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1

Increased morphological asymmetry, evolvability and plasticity in human brain evolution.  

PubMed

The study of hominin brain evolution relies mostly on evaluation of the endocranial morphology of fossil skulls. However, only some general features of external brain morphology are evident from endocasts, and many anatomical details can be difficult or impossible to examine. In this study, we use geometric morphometric techniques to evaluate inter- and intraspecific differences in cerebral morphology in a sample of in vivo magnetic resonance imaging scans of chimpanzees and humans, with special emphasis on the study of asymmetric variation. Our study reveals that chimpanzee-human differences in cerebral morphology are mainly symmetric; by contrast, there is continuity in asymmetric variation between species, with humans showing an increased range of variation. Moreover, asymmetric variation does not appear to be the result of allometric scaling at intraspecific levels, whereas symmetric changes exhibit very slight allometric effects within each species. Our results emphasize two key properties of brain evolution in the hominine clade: first, evolution of chimpanzee and human brains (and probably their last common ancestor and related species) is not strongly morphologically constrained, thus making their brains highly evolvable and responsive to selective pressures; second, chimpanzee and, especially, human brains show high levels of fluctuating asymmetry indicative of pronounced developmental plasticity. We infer that these two characteristics can have a role in human cognitive evolution. PMID:23615289

Gómez-Robles, Aida; Hopkins, William D; Sherwood, Chet C

2013-04-24

2

Genetic contributions to human brain morphology and intelligence.  

PubMed

Variation in gray matter (GM) and white matter (WM) volume of the adult human brain is primarily genetically determined. Moreover, total brain volume is positively correlated with general intelligence, and both share a common genetic origin. However, although genetic effects on morphology of specific GM areas in the brain have been studied, the heritability of focal WM is unknown. Similarly, it is unresolved whether there is a common genetic origin of focal GM and WM structures with intelligence. We explored the genetic influence on focal GM and WM densities in magnetic resonance brain images of 54 monozygotic and 58 dizygotic twin pairs and 34 of their siblings. For genetic analyses, we used structural equation modeling and voxel-based morphometry. To explore the common genetic origin of focal GM and WM areas with intelligence, we obtained cross-trait/cross-twin correlations in which the focal GM and WM densities of each twin are correlated with the psychometric intelligence quotient of his/her cotwin. Genes influenced individual differences in left and right superior occipitofrontal fascicle (heritability up to 0.79 and 0.77), corpus callosum (0.82, 0.80), optic radiation (0.69, 0.79), corticospinal tract (0.78, 0.79), medial frontal cortex (0.78, 0.83), superior frontal cortex (0.76, 0.80), superior temporal cortex (0.80, 0.77), left occipital cortex (0.85), left postcentral cortex (0.83), left posterior cingulate cortex (0.83), right parahippocampal cortex (0.69), and amygdala (0.80, 0.55). Intelligence shared a common genetic origin with superior occipitofrontal, callosal, and left optical radiation WM and frontal, occipital, and parahippocampal GM (phenotypic correlations up to 0.35). These findings point to a neural network that shares a common genetic origin with human intelligence. PMID:17021179

Hulshoff Pol, Hilleke E; Schnack, Hugo G; Posthuma, Danielle; Mandl, René C W; Baaré, Wim F; van Oel, Clarine; van Haren, Neeltje E; Collins, D Louis; Evans, Alan C; Amunts, Katrin; Bürgel, Uli; Zilles, Karl; de Geus, Eco; Boomsma, Dorret I; Kahn, René S

2006-10-01

3

Quantitative genetic modeling of variation in human brain morphology  

Microsoft Academic Search

The degree to which individual variation in brain structure in humans is genetically or environmentally determined is as yet not well understood. We studied the brains of 54 monozygotic (33 male, 21 female) and 58 dizygotic (17 male, 20 female, 21 opposite sex) pairs of twins and 34 of their full siblings (19 male, 15 female) by means of high

W. F. C. Baare; H. E. Hulshoff-Poll; Dorret I. Boomsma; Daniëlle Posthuma; Geus de E. J. C; H. G. Snack; Haren van N. E. M; Oel van C. J; René S. Kahn

2001-01-01

4

Patterns of differences in brain morphology in humans as compared to extant apes.  

PubMed

Although human evolution is characterized by a vast increase in brain size, it is not clear whether or not certain regions of the brain are enlarged disproportionately in humans, or how this enlargement relates to differences in overall neural morphology. The aim of this study is to determine whether or not there are specific suites of features that distinguish the morphology of the human brain from that of apes. The study sample consists of whole brain, in vivo magnetic resonance images (MRIs) of anatomically modern humans (Homo sapiens sapiens) and five ape species (gibbons, orangutans, gorillas, chimpanzees, bonobos). Twenty-nine 3D landmarks, including surface and internal features of the brain were located on 3D MRI reconstructions of each individual using MEASURE software. Landmark coordinate data were scaled for differences in size and analyzed using Euclidean Distance Matrix Analysis (EDMA) to statistically compare the brains of each non-human ape species to the human sample. Results of analyses show both a pattern of brain morphology that is consistently different between all apes and humans, as well as patterns that differ among species. Further, both the consistent and species-specific patterns include cortical and subcortical features. The pattern that remains consistent across species indicates a morphological reorganization of 1) relationships between cortical and subcortical frontal structures, 2) expansion of the temporal lobe and location of the amygdala, and 3) expansion of the anterior parietal region. Additionally, results demonstrate that, although there is a pattern of morphology that uniquely defines the human brain, there are also patterns that uniquely differentiate human morphology from the morphology of each non-human ape species, indicating that reorganization of neural morphology occurred at the evolutionary divergence of each of these groups. PMID:21056456

Aldridge, Kristina

2010-11-05

5

Human brain potentials indicate morphological decomposition in visual word recognition  

Microsoft Academic Search

Stem homographs are pairs of words with the same orthographic description of their stem but which are semantically and morphologically unrelated (e.g. in Spanish: rata\\/rato (rat\\/moment)). In priming tasks, stem homographs produce inhibition, unlike morphologically related words (loca\\/loco (madwoman\\/madman)) which produce facilitation. An event-related potentials study was conducted to compare morphological and stem homographic priming effects. The results show a

Horacio Barber; Alberto Dom??nguez; Manuel de Vega

2002-01-01

6

Chronic cigarette smoking and heavy drinking in human immunodeficiency virus: consequences for neurocognition and brain morphology  

PubMed Central

Alcohol use disorders (AUD) and chronic cigarette smoking are common among individuals with human immunodeficiency virus infection (HIV). Concurrent AUD in HIV is related to greater abnormalities in brain morphology and neurocognition than either condition alone. However, the potential influence of chronic smoking on brain morphology and neurocognition in those concurrently afflicted with AUD and HIV has not been examined. The goal of this retrospective analysis was to determine if chronic smoking affected neurocognition and brain morphology in a subsample of HIV-positive non–treatment-seeking heavy drinking participants (HD+) from our earlier work. Regional volumetric and neurocognitive comparisons were made among age-equivalent smoking HD+(n = 17), nonsmoking HD+(n = 27), and nonsmoking HIV-negative light drinking controls (n = 27) obtained from our original larger sample. Comprehensive neuropsychological assessment evaluated multiple neurocognitive domains of functioning and for potential psychiatric comorbidities. Quantitative volumetric measures of neocortical gray matter (GM), white matter (WM), subcortical structures, and sulcal and ventricular cerebral spinal fluid (CSF) were derived from high-resolution magnetic resonance images. The main findings were (1) smoking HD+ performed significantly worse than nonsmoking HD+ on measures of auditory-verbal (AV) learning, AV memory, and cognitive efficiency; (2) relative to controls, smoking HD+ demonstrated significantly lower neocortical GM volumes in all lobes except the occipital lobe, while nonsmoking HD+ showed only lower frontal GM volume compared with controls; (3) in the HD+ group, regional brain volumes and neurocognition were not influenced by viremia, highly active antiretroviral treatment, or Center for Disease Control symptom status, and no interactions were apparent with these variables or smoking status. Overall, the findings suggested that the direct and/or indirect effects of chronic cigarette smoking created an additional burden on the integrity of brain neurobiology and neurocognition in this cohort of HIV-positive heavy drinkers.

Durazzo, Timothy C.; Rothlind, Johannes C.; Cardenas, Valerie A.; Studholme, Colin; Weiner, Michael W.; Meyerhoff, Dieter J.

2008-01-01

7

Dyslexia and Brain Morphology  

Microsoft Academic Search

Although the neurological basis of dyslexia has long been assumed, little direct evidence documents a relation between deviations in brain morphology and behavioral correlates of dyslexia. This article reviews two sources of evidence. Results of CT\\/MRI studies suggest that in the brains of dyslexics there is an increased incidence of symmetry in the region of the planum temporale and parietooccipital

George W. Hynd; Margaret Semrud-Clikeman

1989-01-01

8

Morphology of neurons in the anterior hypothalamic area and supraoptic hypothalamic nucleus of the adult human brain  

Microsoft Academic Search

Morphological features of neuronal cell types in the anterior hypothalamic area (AHA) and supraoptic hypothalamic nucleus (SON) of the adult human brain were analysed in Golgi impregnated preparations. Four neuronal cell types were described for the first time in these human nuclei. Type I neurons were found in both the AHA and SON, while the other three cell types (types

S. Al-Hussain; R. Al-Jomard

1996-01-01

9

Early parental care is important for hippocampal maturation: Evidence from brain morphology in humans  

Microsoft Academic Search

The effects of early life experience on later brain structure and function have been studied extensively in animals, yet the relationship between childhood experience and normal brain development in humans remains largely unknown. Using a unique longitudinal data set including ecologically valid in-home measures of early experience during childhood (at age 4 and 8 years) and high-resolution structural brain imaging during

Hengyi Rao; Laura Betancourt; Joan M. Giannetta; Nancy L. Brodsky; Marc Korczykowski; Brian B. Avants; James C. Gee; Jiongjiong Wang; Hallam Hurt; John A. Detre; Martha J. Farah

2010-01-01

10

Brain Morphological Changes and Early Marijuana Use  

Microsoft Academic Search

Background: The focus of this report is on the possible role that the age of first use of marijuana may play on brain morphology and function.Methods: Magnetic resonance imaging (MRI) and positron emission tomography (PET) were utilized to study 57 subjects. Brain volume measures (whole brain, gray matter, white matter and lateral ventricle volumes), global cerebral blood flow (CBF) and

William Wilson; Roy Mathew; Timothy Turkington; Thomas Hawk; R. Edward Coleman; James Provenzale

2000-01-01

11

Genetic topography of brain morphology.  

PubMed

Animal data show that cortical development is initially patterned by genetic gradients largely along three orthogonal axes. We previously reported differences in genetic influences on cortical surface area along an anterior-posterior axis using neuroimaging data of adult human twins. Here, we demonstrate differences in genetic influences on cortical thickness along a dorsal-ventral axis in the same cohort. The phenomenon of orthogonal gradations in cortical organization evident in different structural and functional properties may originate from genetic gradients. Another emerging theme of cortical patterning is that patterns of genetic influences recapitulate the spatial topography of the cortex within hemispheres. The genetic patterning of both cortical thickness and surface area corresponds to cortical functional specializations. Intriguingly, in contrast to broad similarities in genetic patterning, two sets of analyses distinguish cortical thickness and surface area genetically. First, genetic contributions to cortical thickness and surface area are largely distinct; there is very little genetic correlation (i.e., shared genetic influences) between them. Second, organizing principles among genetically defined regions differ between thickness and surface area. Examining the structure of the genetic similarity matrix among clusters revealed that, whereas surface area clusters showed great genetic proximity with clusters from the same lobe, thickness clusters appear to have close genetic relatedness with clusters that have similar maturational timing. The discrepancies are in line with evidence that the two traits follow different mechanisms in neurodevelopment. Our findings highlight the complexity of genetic influences on cortical morphology and provide a glimpse into emerging principles of genetic organization of the cortex. PMID:24082094

Chen, Chi-Hua; Fiecas, Mark; Gutiérrez, E D; Panizzon, Matthew S; Eyler, Lisa T; Vuoksimaa, Eero; Thompson, Wesley K; Fennema-Notestine, Christine; Hagler, Donald J; Jernigan, Terry L; Neale, Michael C; Franz, Carol E; Lyons, Michael J; Fischl, Bruce; Tsuang, Ming T; Dale, Anders M; Kremen, William S

2013-09-30

12

Imaging brain morphology with ultrahigh-resolution optical coherence tomography  

NASA Astrophysics Data System (ADS)

The morphology of healthy and pathological human brain tissue, as well as the brain structural organization of various animal models has been imaged in-vitro using ultrahigh resolution optical coherence tomography (UHR OCT). Micrometer-scale OCT resolution (< 2 ?m axial resolution) was achieved at different central wavelengths by interfacing three state-of-the-art broad bandwidth light sources (Ti:Al2O3, ?c = 790 nm, ?? = 260 nm and Pout = 50 mW; PCF based laser, ?c = 1150 nm, ?? = 350 nm and Pout = 2 W; Fiber laser based light source, ?c = 1350 nm, ?? = 470 nm and Pout = 4 mW) to a modular free-space OCT system, utilizing a dynamic focusing and designed for optimal performance in the appropriate wavelength regions. Images acquired from a fixed honeybee brain demonstrated the ability of UHR OCT to image the globular structure of the brain, some fine morphological details such as the nerve fiber bundles connecting the medulla (visual center) to the honeybee eyes, and the interfaces between different tissue layers in the medulla. Tomograms of various human neuropathologies demonstrated the feasibility of UHR OCT to visualize morphological details such as small (~20 ?m) calcifications typical for fibrous meningioma, and enlarged nuclei of cancer cells (~10-15 ?m) characteristic for many other neuropathologies. In addition UHR OCT was used to image cellular morphology in living ganglion cells.

Bizheva, Kostadinka K.; Unterhuber, Angelika; Hermann, Boris; Povazay, Boris; Sattmann, Harald; Mei, Michael; Holzwarth, Ronald; Preusser, Matthias; Reitsamer, Herbert; Seefeldt, Michael; Menzel, Ralf; Budka, Herbert; Fercher, Adolf F.; Drexler, Wolfgang

2003-10-01

13

Measuring Complexity of Mouse Brain Morphological Changes Using GeoEntropy  

NASA Astrophysics Data System (ADS)

Given the current emphasis on research into human neurodegenerative diseases, an effective computing approach for the analysis of complex brain morphological changes would represent a significant technological innovation. The availability of mouse models of such disorders provides an experimental system to test novel approaches to brain image analysis. Here we utilize a mouse model of a neurodegenerative disorder to model changes to cerebellar morphology during the postnatal period, and have applied the GeoEntropy algorithm to measure the complexity of morphological changes.

El-Fiqi, Heba Z.; Pham, Tuan D.; Hattori, Haroldo T.; Crane, Denis I.

2010-01-01

14

Brain Anatomical Networks in Early Human Brain Development  

PubMed Central

Recent neuroimaging studies have demonstrated that human brain networks have economic small-world topology and modular organization, enabling efficient information transfer among brain regions. However, it remains largely unknown how the small-world topology and modular organization of human brain networks emerge and develop. Using longitudinal MRI data of 28 healthy pediatric subjects, collected at their ages of 1 month, 1 year, and 2 years, we analyzed development patterns of brain anatomical networks derived from morphological correlations of brain regional volumes. The results show that the brain network of 1-month-olds has the characteristically economic small-world topology and nonrandom modular organization. The network’s cost efficiency increases with the brain development to 1 year and 2 years, so does the modularity, providing supportive evidence for the hypothesis that the small-world topology and the modular organization of brain networks are established during early brain development to support rapid synchronization and information transfer with minimal rewiring cost, as well as to balance between local processing and global integration of information.

Fan, Yong; Shi, Feng; Smith, Jeffrey Keith; Lin, Weili; Gilmore, John H.; Shen, Dinggang

2011-01-01

15

Changes in brain morphology in patients with obstructive sleep apnoea  

Microsoft Academic Search

BackgroundObstructive sleep apnoea (OSA) is a common disease that leads to daytime sleepiness and cognitive impairment. Attempts to investigate changes in brain morphology that may underlie these impairments have led to conflicting conclusions. This study was undertaken to aim to resolve this confusion, and determine whether OSA is associated with changes in brain morphology in a large group of patients

M J Morrell; M L Jackson; G L Twigg; R Ghiassi; D W McRobbie; R A Quest; H Pardoe; G S Pell; D F Abbott; P D Rochford; G D Jackson; R J Pierce; F J ODonoghue; D R Corfield

2010-01-01

16

Genomic imprinting effects of the X chromosome on brain morphology.  

PubMed

There is increasing evidence that genomic imprinting, a process by which certain genes are expressed in a parent-of-origin-specific manner, can influence neurogenetic and psychiatric manifestations. While some data suggest possible imprinting effects of the X chromosome on physical and cognitive characteristics in humans, there is no compelling evidence that X-linked imprinting affects brain morphology. To address this issue, we investigated regional cortical volume, thickness, and surface area in 27 healthy controls and 40 prepubescent girls with Turner syndrome (TS), a condition caused by the absence of one X chromosome. Of the young girls with TS, 23 inherited their X chromosome from their mother (X(m)) and 17 from their father (X(p)). Our results confirm the existence of significant differences in brain morphology between girls with TS and controls, and reveal the presence of a putative imprinting effect among the TS groups: girls with X(p) demonstrated thicker cortex than those with X(m) in the temporal regions bilaterally, while X(m) individuals showed bilateral enlargement of gray matter volume in the superior frontal regions compared with X(p). These data suggest the existence of imprinting effects of the X chromosome that influence both cortical thickness and volume during early brain development, and help to explain variability in cognitive and behavioral manifestations of TS with regard to the parental origin of the X chromosome. PMID:23658194

Lepage, Jean-Francois; Hong, David S; Mazaika, Paul K; Raman, Mira; Sheau, Kristen; Marzelli, Matthew J; Hallmayer, Joachim; Reiss, Allan L

2013-05-01

17

Development of human brain  

Microsoft Academic Search

The human has the most complex brain of the primates group. Their development is prolonged beyond birth and it is not completed\\u000a structurally nor neurochemically until age of 20 years. Decades later, degenerative phenomena begin to be evident, that little\\u000a by little will drive us to death. At the end of the life, 113 grams aproximate of cerebral mass are

A. Peña-Melian

2000-01-01

18

Glutathione S-transferase in human brain.  

PubMed

The glutathione S-transferases are a complex group of multifunctional enzymes which may detoxify a wide range of toxic substances including drugs and carcinogens. Different isoenzymes vary in substrate specificity, tissue distribution and level of expression during development. Following reports of cell-specific and age-dependent expression in rat brain we have studied, immunohistochemically, expression of the Pi and Alpha class isoenzymes in 10 adult and 21 human fetal brains. Whilst Alpha isoenzyme is expressed only in adult brain, and then only focally, Pi isoenzyme is strongly expressed from as early as 12 weeks gestation. In the adult, expression is localized to choroid plexus, vascular endothelium, ventricular lining cells, pia-arachnoid and astrocytes. In fetal brain, expression is also strong in cells with the morphology of tanycytes and in the cell bodies of radial glia. Neurons are consistently negative. Pi isoenzyme thus localizes to the sites of the blood-CSF barrier, blood-brain barrier, CSF-brain barrier and pia-arachnoid-brain barrier. It is ideally placed to regulate neuronal exposure to potentially toxic substances derived from blood or cerebrospinal fluid. Expression so early in gestation is of significance and may imply a role in protection of the developing human brain. PMID:2234311

Carder, P J; Hume, R; Fryer, A A; Strange, R C; Lauder, J; Bell, J E

1990-08-01

19

Morphological abnormalities in the brains of estrogen receptor knockout mice  

Microsoft Academic Search

Estrogen receptor (ER) is expressed at high levels in both neurons and glial cells of the central nervous system. The development of ER knockout (BERKO) mice has provided a model to study the function of this nuclear receptor in the brain. We have found that the brains of BERKO mice show several morphological abnormalities. There is a regional neuronal hypocellularity

Ling Wang; Sandra Andersson; Margaret Warner; Jan-Åke Gustafsson

2001-01-01

20

Genes and human brain evolution  

PubMed Central

Several genes were duplicated during human evolution. It seems that one such duplication gave rise to a gene that may have helped to make human brains bigger and more adaptable than those of our ancestors.

Geschwind, Daniel H.; Konopka, Genevieve

2013-01-01

21

Steroidogenic Enzymes in the Brain: Morphological Aspects  

Microsoft Academic Search

It is now well documented that brain tissue is capable of synthesizing de novo bioactive steroids, named neurosteroids, which are involved in the regulation of various functions in the brain, including behavioral, neuroendocrine and metabolic processes. In this chapter, we have summarized the current knowledge about the expression of enzymes involved in the biosynthesis and metabolism of steroids in the

Georges Pelletier

2010-01-01

22

Educating the Human Brain. Human Brain Development Series  

ERIC Educational Resources Information Center

|"Educating the Human Brain" is the product of a quarter century of research. This book provides an empirical account of the early development of attention and self regulation in infants and young children. It examines the brain areas involved in regulatory networks, their connectivity, and how their development is influenced by genes and…

Posner, Michael I.; Rothbart, Mary K.

2006-01-01

23

Morphology and histology of chimpanzee primary visual striate cortex indicate that brain reorganization predated brain expansion in early hominid evolution.  

PubMed

Human brain evolution is characterized by an overall increase in brain size, cerebral reorganization, and cerebral lateralization. It is generally understood when brain enlargement occurred during human evolution. However, issues concerning cerebral reorganization and hemispheric lateralization are more difficult to determine from brain endocasts, and they are topics of considerable debate. One region of the cerebral cortex that may represent the earliest evidence for brain reorganization is the primary visual cortex (PVC), or area 17 of Brodmann. In nonhuman primates, this region is larger in volume (demarcated anteriorly by the lunate sulcus), and extends further rostrally than it does in modern humans. In early hominid fossil (Australopithecus) endocasts, this region appears to occupy a smaller area compared to that in nonhuman primates. Some have argued that the brain first underwent size expansion prior to reorganization, while others maintain that reorganization predated brain expansion. To help resolve this question, we provide a description of two male, common chimpanzee (Pan troglodytes) brains, YN77-111 and YN92-115, which clearly display a more posterior lunate sulcal morphology than seen in other chimpanzees. These data show that neurogenetic variability exists in chimpanzees, and that significant differences in organization (e.g., a reduced PVC) can predate brain enlargement. While the human brain has experienced numerous expansion and reorganization events throughout evolution, the data from these two chimpanzees offer significant support for the hypothesis that the neurogenetic basis for brain reorganization was present in our early fossil ancestors (i.e., the australopithecines) prior to brain enlargement. PMID:12808644

Holloway, Ralph L; Broadfield, Douglas C; Yuan, Michael S

2003-07-01

24

A Morphological Theory of Human Hearing  

NASA Astrophysics Data System (ADS)

The interdisciplinary project motivating the work discussed in this paper aims at developing an integrated framework of ideas for human hearing research. The novelty of the project consists in combining the history and philosophy of sound perception in humans with psychoacoustics and mechanics of hearing. In this paper, I present a morphological theory of human hearing, which replaces the concept of tonopic representation in the cochlea which the concept of morphological representation.

Pamieri, Paolo

2011-11-01

25

Genetics of human brain oscillations  

Microsoft Academic Search

In the last three decades, much emphasis has been placed on neural oscillations in vitro, in vivo, as well as in the human brain. These brain oscillations have been studied extensively in the resting electroencephalogram (EEG), as well as in the underlying evoked oscillations that make up the event-related potentials (ERPs). There are several approaches to elucidate the possible mechanisms

Henri Begleiter; Bernice Porjesz

2006-01-01

26

Transient response of human brain  

Microsoft Academic Search

The aim or this study is the improvement of the relationship between the operators and robotics in CIM room, teaching room and students. It is said that we human beings are controlled by the left brain for the intelligent quality (IQ) and by the right brain for the emotional quality (EQ). The blood pressure and frequency. the face temperature and

Takashi MORIYAMA; M. Miyauchi; T. Miyagawa; S. Fujiwara

2002-01-01

27

Archaic and modern human distal humeral morphology.  

PubMed

The morphology of the proximal ulna has been shown to effectively differentiate archaic or premodern humans (such as Homo heidelbergensis and H. neanderthalensis) from modern humans (H. sapiens). Accordingly, the morphology of adjacent, articulating elements should be able to distinguish these two broad groups as well. Here we test the taxonomic utility of another portion of the elbow, the distal humerus, as a discriminator of archaic and modern humans. Principal components analysis was employed on a suite of log-raw and log-shape distal humeral measures to examine differences between Neandertal and modern human distal humeri. In addition, the morphological affinities of Broken Hill (Kabwe) E.898, an archaic human distal humeral fragment from the middle Pleistocene of Zambia, and five Pliocene and early Pleistocene australopith humeri were assessed. The morphometric analyses effectively differentiated the Neandertals from the other groups, while the Broken Hill humerus appears morphologically similar to modern human distal humeri. Thus, an archaic/modern human dichotomy-as previously reported for proximal ulnar morphology-is not supported with respect to distal humeral morphology. Relative to australopiths and modern humans, Neandertal humeri are characterized by large olecranon fossae and small distodorsal medial and lateral pillars. The seeming disparity in morphological affinities of proximal ulnae (in which all archaic human groups appear distinct from modern humans) and distal humeri (in which Neandertals appear distinct from modern humans, but other archaic humans do not) is probably indicative of a highly variable, possibly transitional population of which our knowledge is hampered by sample-size limitations imposed by the scarcity of middle-to-late Pleistocene premodern human fossils outside of Europe. PMID:16959299

Yokley, Todd R; Churchill, Steven E

2006-07-21

28

Elephant brain. Part I: gross morphology, functions, comparative anatomy, and evolution.  

PubMed

We report morphological data on brains of four African, Loxodonta africana, and three Asian elephants, Elephas maximus, and compare findings to literature. Brains exhibit a gyral pattern more complex and with more numerous gyri than in primates, humans included, and in carnivores, but less complex than in cetaceans. Cerebral frontal, parietal, temporal, limbic, and insular lobes are well developed, whereas the occipital lobe is relatively small. The insula is not as opercularized as in man. The temporal lobe is disproportionately large and expands laterally. Humans and elephants have three parallel temporal gyri: superior, middle, and inferior. Hippocampal sizes in elephants and humans are comparable, but proportionally smaller in elephant. A possible carotid rete was observed at the base of the brain. Brain size appears to be related to body size, ecology, sociality, and longevity. Elephant adult brain averages 4783 g, the largest among living and extinct terrestrial mammals; elephant neonate brain averages 50% of its adult brain weight (25% in humans). Cerebellar weight averages 18.6% of brain (1.8 times larger than in humans). During evolution, encephalization quotient has increased by 10-fold (0.2 for extinct Moeritherium, approximately 2.0 for extant elephants). We present 20 figures of the elephant brain, 16 of which contain new material. Similarities between human and elephant brains could be due to convergent evolution; both display mosaic characters and are highly derived mammals. Humans and elephants use and make tools and show a range of complex learning skills and behaviors. In elephants, the large amount of cerebral cortex, especially in the temporal lobe, and the well-developed olfactory system, structures associated with complex learning and behavioral functions in humans, may provide the substrate for such complex skills and behavior. PMID:16782503

Shoshani, Jeheskel; Kupsky, William J; Marchant, Gary H

2006-04-18

29

Brain morphology and sleep EEG in patients with Huntington's disease  

Microsoft Academic Search

Summary In 12 patients with Huntington's disease, the relationship between brain morphology, nocturnal sleep EEG, and clinical variables was studied. Global cerebral atrophy did not significantly correlate with sleep parameters, whereas atrophy of the caudate nuclei was associated with reduced slow wave sleep and increased time spent awake. Several clinical parameters (e.g., anergia and thought disturbance scores of the Brief

Michael Wiegand; Arnulf A. Möller; Wolfgang Schreiber; Christoph Lauer; Jiirgen-Christian Krieg

1991-01-01

30

Childhood behavioral characteristics and adult brain morphology in schizophrenia  

Microsoft Academic Search

It is well established that many schizophrenia patients manifest behavioral dysfunction long before the onset of clinical symptoms of illness. Some show signs of motor and socioemotional deficit as early as infancy. The present study examines the relations among childhood neuromotor, affective and behavior characteristics, and the association of these factors with adult brain morphology (MRI) in schizophrenia patients. Data

Elaine F. Walker; Richard R. J. Lewine; Craig Neumann

1996-01-01

31

Developmental dyslexia, neurolinguistic theory and deviations in brain morphology  

Microsoft Academic Search

Although some form of central nervous system involvement is presumed, evidence establishing a relationship between dyslexia and neurological dysfunction has been correlational. Recently, neuroimaging and postmortem studies have begun to provide direct evidence implicating neuropathological structures in dyslexia. This article reviews computed tomography (CT) and magnetic resonance imaging (MRI) studies examining deviations in brain morphology which appear to be associated

George W. Hynd; Richard M. Marshall; Margaret Semrud-Clikeman

1991-01-01

32

Functional brain development in humans  

Microsoft Academic Search

There is a continuing debate in developmental neuroscience about the importance of activity-dependent processes. The relatively delayed rate of development of the human brain, compared with that of other mammals, might make it more susceptible to the influence of postnatal experience. The human infant is well adapted to capitalize on this opportunity through primitive biases to attend to relevant stimuli

Mark H. Johnson

2001-01-01

33

Organization of the human brain.  

PubMed

Examination of structure-function correlates in the human brain reveals that there is a high degree of functional specificity in the information transmitted over neural systems. It also appears that the human brain has a modular organization consisting of identifiable component processes that participate in the generation of a cognitive state. The effects of isolating entire modular systems or of disconnecting the component parts can be observed. The features of a left hemisphere specialized capacity to interpret the actions of modules are discussed in terms of human consciousness. PMID:2672334

Gazzaniga, M S

1989-09-01

34

Hominins and the emergence of the modern human brain.  

PubMed

Evidence used to reconstruct the morphology and function of the brain (and the rest of the central nervous system) in fossil hominin species comes from the fossil and archeological records. Although the details provided about human brain evolution are scarce, they benefit from interpretations informed by interspecific comparative studies and, in particular, human pathology studies. In recent years, new information has come to light about fossil DNA and ontogenetic trajectories, for which pathology research has significant implications. We briefly describe and summarize data from the paleoarcheological and paleoneurological records about the evolution of fossil hominin brains, including behavioral data most relevant to brain research. These findings are brought together to characterize fossil hominin taxa in terms of brain structure and function and to summarize brain evolution in the human lineage. PMID:22230633

de Sousa, Alexandra; Cunha, Eugénia

2012-01-01

35

Apolipoprotein E Polymorphism and Brain Morphology in Mild Cognitive Impairment  

Microsoft Academic Search

Background: The apolipoprotein E (ApoE) genotype has been confirmed as the major genetic risk factor for late-onset Alzheimer’s disease (AD). How the ApoE genotype and brain morphology relate to each other is only partly understood, particularly in mild cognitive impairment, the assumed prestage of AD. Methods: A total of 83 subjects with mild cognitive impairment (aging-associated cognitive decline criteria) were

Philipp A. Thomann; Ann-Sophie Roth; Vasco Dos Santos; Pablo Toro; Marco Essig; Johannes Schröder

2008-01-01

36

Developmental Dyslexia, Neurolinguistic Theory and Deviations in Brain Morphology  

Microsoft Academic Search

\\u000a Although some form of central nervous system involvement is presumed, evidence establishing a relationship between dyslexia\\u000a and neurological dysfunction has been correlational. Recently, neuroimaging and postmortem studies have begun to provide direct\\u000a evidence implicating neuropathological structures in dyslexia. This article reviews computed tomography (CT) and magnetic\\u000a resonance imaging (MRI) studies examining deviations in brain morphology which appear to be associated

George W. Hynd; Richard M. Marshall; Margaret Semrud-Clikeman

37

Effects of abstinence on brain morphology in alcoholism  

Microsoft Academic Search

Chronic alcohol abuse leads to morphological changes of the brain. We investigated if these volumetric changes are reversible\\u000a after a period of abstinence. For this reason 41 male and 15 female alcohol patients underwent MRI-scanning after in-patient\\u000a detoxification (baseline) entering alcoholism treatment programs, and between 6 and 9 months later (follow-up), in a phase\\u000a of convalescence. Additionally, 29 male and 16

Thomas Wobrock; Peter Falkai; Thomas Schneider-Axmann; Nicole Frommann; Wolfgang Wölwer; Wolfgang Gaebel

2009-01-01

38

The ``Affenspalte'' in Human Brains  

Microsoft Academic Search

WILL you kindly allow me the privilege of using your columns for the following note? In a recent number of the Anatomischer Anzeiger Prof. Elliott Smith published a most interesting forecast of an extensive work which he has in hand, dealing particularly with the occurrence in human brains of an occipital operculum; this occurrence had been considered previously as very

W. L. H. Duckworth

1903-01-01

39

Human-specific transcriptional networks in the brain.  

PubMed

Understanding human-specific patterns of brain gene expression and regulation can provide key insights into human brain evolution and speciation. Here, we use next-generation sequencing, and Illumina and Affymetrix microarray platforms, to compare the transcriptome of human, chimpanzee, and macaque telencephalon. Our analysis reveals a predominance of genes differentially expressed within human frontal lobe and a striking increase in transcriptional complexity specific to the human lineage in the frontal lobe. In contrast, caudate nucleus gene expression is highly conserved. We also identify gene coexpression signatures related to either neuronal processes or neuropsychiatric diseases, including a human-specific module with CLOCK as its hub gene and another module enriched for neuronal morphological processes and genes coexpressed with FOXP2, a gene important for language evolution. These data demonstrate that transcriptional networks have undergone evolutionary remodeling even within a given brain region, providing a window through which to view the foundation of uniquely human cognitive capacities. PMID:22920253

Konopka, Genevieve; Friedrich, Tara; Davis-Turak, Jeremy; Winden, Kellen; Oldham, Michael C; Gao, Fuying; Chen, Leslie; Wang, Guang-Zhong; Luo, Rui; Preuss, Todd M; Geschwind, Daniel H

2012-08-23

40

Human Visual Brain  

Microsoft Academic Search

Objects in the visual scene are defined by different cues such as colour and motion. Through the integration of these cues the visual system is able to utilize different sources of information, thus enhancing its ability to discriminate objects from their backgrounds. In the following experiments, we investigate the neural mechanisms of cue integration in the human. We show, using

Matthew W. Self; S. Zeki

41

Detection of blood vessels in human brain 3D magnetic resonance images with the use of mathematical morphology and region growing algorithms  

NASA Astrophysics Data System (ADS)

Detection and quantitative parameterization of brain blood vessels in magnetic resonance images (MRI) are an important aid to diagnosing neoplasmic diseases, planning surgical operations or detecting the atrophy of blood vessels. Fast and effective computer programs are needed to extract quantitative information from MRI data - to increase objectivity, accuracy and repeatability of the diagnosis. To develop such programs we must use algorithms for 3D images segmentation, necessary to build geometrical models of the blood vessels. These models are then used for vessel tree visualization and quantitative description.

Sankowski, Adam; Materka, Andrzej

2009-06-01

42

Morphology and digitally aided morphometry of the human paracentral lobule.  

PubMed

The human paracentral lobule, the junction of the precentral and postcentral gyri at the medial hemispheric surface, contains several important functional regions, and its variable morphology requires exact morphological and quantitativedata. In order to obtain precise data we investigated the morphology of the paracentral lobule and quantified its visible (extrasulcal) surface. This surface corresponds to commonly used magnetic resonance imaging scout images. We studied 84 hemispheres of adult persons (42 brains; 26 males and 16 females; 20-65 years) fixed in neutral formalin for at least 4 weeks. The medial hemispheric surface was photographed at standard distance and each digital photo was calibrated. Using the intercommissural line system (commissura anterior-commissura posterior or CA-CP line), we performed standardised measurements of the paracentral lobule. Exact determination of its boundaries and morphological types was followed by digital morphometry of its extrasulcal surface using AutoCAD software. We found two distinct morphological types of the human paracentral lobule: continuous type, which was predominant (95.2%), and rare segmented type (4.8%). In hemispheres with segmented cingulate sulcus we also found the short transitional lobulo-limbic gyrus (13.1%). The mean extrasulcal surface of the left paracentral lobule was significantly larger, both in males (left 6.79 cm2 vs. right 5.76 cm2) and in females (left 6.05 cm2 vs. right 5.16 cm2). However, even larger average surfaces in males were not significantly different than the same in females. Reported morphological and quantitative data will be useful during diagnostics and treatment of pathologies affecting the human paracentral lobule, and in further studies of its cytoarchitectonic and functional parcellations. PMID:23749705

Spasojevi?, Goran; Malobabic, Slobodan; Pilipovi?-Spasojevi?, Olivera; Djuki?-Macut, Nataša; Malikovi?, Aleksandar

2013-02-01

43

Neurogenesis in adult human brain after traumatic brain injury.  

PubMed

Abstract While much work has been conducted regarding the neurogenesis response to traumatic brain injury (TBI) in rodents, it remains largely unknown whether neurogenesis in adult human brain also responds to TBI in a similar manner. Here, we performed immunocytochemistry on 11 brain specimens from patients with traumatic brain injury, who underwent surgical intervention. We found that expression of neural stem/progenitor cell (NSC) protein markers, including DCX, TUC4, PSA-NCAM, SOX2 and NeuroD, was increased in the perilesional cortex of human brain after TBI compared to that of normal brain. Confocal images showed that these NSC proteins were expressed in one single cell. We also found that proliferative markers were expressed in NSC protein-positive cells after TBI, and the number of proliferative NSCs was significantly increased after TBI. Our data suggest that TBI may also induce neurogenesis in human brain. PMID:21275797

Zheng, Weiming; Zhuge, Qichuan; Zhong, Ming; Chen, Gourong; Shao, Bei; Wang, Hong; Mao, Xiaoou; Xie, Lin; Jin, Kunlin

2013-07-24

44

Creativity, a resource of the human brain  

Microsoft Academic Search

The purpose of this article is to show how the human brain is able to produce creative ideas. It is suggested, on the basis of the author's own empirical work on the ontogenetic development of brain functions, that the brain is a system, a dipole, consisting of a chaos-generator and an order-generator. In between is the brain's neurophysiological \\

Matti Bergström

1991-01-01

45

Towards multimodal atlases of the human brain  

Microsoft Academic Search

Atlases of the human brain have an important impact on neuroscience. The emergence of ever more sophisticated imaging techniques, brain mapping methods and analytical strategies has the potential to revolutionize the concept of the brain atlas. Atlases can now combine data describing multiple aspects of brain structure or function at different scales from different subjects, yielding a truly integrative and

Paul M. Thompson; Susumu Mori; Katrin Amunts; Karl Zilles; Arthur W. Toga

2006-01-01

46

Tracking hierarchical processing in morphological decomposition with brain potentials.  

PubMed

One important debate in psycholinguistics concerns the nature of morphological decomposition processes in visual word recognition (e.g., darkness = {dark} + {-ness}). One theory claims that these processes arise during orthographic analysis and prior to accessing meaning (Rastle & Davis, 2008), and another argues that these processes arise through greater temporal overlap between the activation of orthographic and semantic information (Feldman, O'Connor, & Moscoso del Prado Martín, 2009). This issue has been the subject of intense debate in studies using masked priming but has yet to be resolved unequivocally. The present study takes another approach to resolving this controversy by examining brain potentials as participants made lexical decisions to unprimed morphological (darkness), pseudomorphological (corner), and nonmorphological (brothel) stimuli. Results revealed a difference from ?190 ms between the nonmorphological condition and the other 2 conditions (which showed no differentiation), a likely correlate of morphological processing reliant exclusively on orthography. Only 60-70 ms later was there evidence of the activation of semantic information, when the pseudomorphological condition diverged from the other 2 conditions. These results provide unambiguous support for a hierarchical model of morphological processing whereby decomposition is based initially on orthographic analysis and is only later constrained by semantic information. (PsycINFO Database Record (c) 2012 APA, all rights reserved). PMID:22686695

Lavric, Aureliu; Elchlepp, Heike; Rastle, Kathleen

2012-06-11

47

Longitudinal Characterization of Brain Atrophy of a Huntington Disease Mouse Model by Automated Morphological Analyses of Magnetic Resonance Images  

PubMed Central

Mouse models of human diseases play crucial roles in understanding disease mechanisms and developing therapeutic measures. Huntington’s disease (HD) is characterized by striatal atrophy that begins long before the onset of motor symptoms. In symptomatic HD, striatal volumes decline predictably with disease course. Thus, imaging based volumetric measures have been proposed as outcomes for presymptomatic as well as symptomatic clinical trials of HD. Magnetic resonance imaging of the mouse brain structures is becoming widely available and has been proposed as one of the biomarkers of disease progression and drug efficacy testing. However, three-dimensional and quantitative morphological analyses of the brains are not straightforward. In this paper, we describe a tool for automated segmentation and voxel-based morphological analyses of the mouse brains. This tool was applied to a well-established mouse model of Huntington disease, the R6/2 transgenic mouse strain. Comparison between the automated and manual segmentation results showed excellent agreement in most brain regions. The automated method was able to sensitively detect atrophy as early as 3 weeks of age and accurately follow disease progression. Comparison between ex vivo and in vivo MRI suggests that the ex vivo end-point measurement of brain morphology is also a valid approach except for the morphology of the ventricles. This is the first report of longitudinal characterization of brain atrophy in a mouse model of Huntington’s disease by using automatic morphological analysis.

Zhang, Jiangyang; Peng, Qi; Li, Qing; Jahanshad, Neda; Hou, Zhipeng; Jiang, Mali; Masuda, Naoki; Langbehn, Douglas R.; Miller, Michael I.; Mori, Susumu; Ross, Christopher A.; Duan, Wenzhen

2010-01-01

48

Bazooka mediates secondary axon morphology in Drosophila brain lineages  

PubMed Central

In the Drosophila brain, neural lineages project bundled axon tracts into a central neuropile. Each lineage exhibits a stereotypical branching pattern and trajectory, which distinguish it from other lineages. In this study, we used a multilineage approach to explore the neural function of the Par-complex member Par3/Bazooka in vivo. Drosophila bazooka is expressed in post-mitotic neurons of the larval brain and localizes within neurons in a lineage-dependent manner. The fact that multiple GAL4 drivers have been mapped to several lineages of the Drosophila brain enables investigation of the role of Bazooka from larval to adult stages Bazooka loss-of-function (LOF) clones had abnormal morphologies, including aberrant pathway choice of ventral projection neurons in the BAla1 lineage, ectopic branching in the DALv2 and BAmv1 lineages, and excess BLD5 lineage axon projections in the optic medulla. Exogenous expression of Bazooka protein in BAla1 neurons rescued defective guidance, supporting an intrinsic requirement for Bazooka in the post-mitotic neuron. Elimination of the Par-complex member Par6 recapitulated Bazooka phenotypes in some but not all lineages, suggesting that the Par complex functions in a lineage-dependent manner, and that Bazooka may act independently in some lineages. Importantly, this study highlights the potential of using a multilineage approach when studying gene function during neural development in Drosophila.

2011-01-01

49

Genetic basis of human brain evolution.  

PubMed

Human evolution is characterized by a rapid increase in brain size and complexity. Decades of research have made important strides in identifying anatomical and physiological substrates underlying the unique features of the human brain. By contrast, it has become possible only very recently to examine the genetic basis of human brain evolution. Through comparative genomics, tantalizing insights regarding human brain evolution have emerged. The genetic changes that potentially underlie human brain evolution span a wide range from single-nucleotide substitutions to large-scale structural alterations of the genome. Similarly, the functional consequences of these genetic changes vary greatly, including protein-sequence alterations, cis-regulatory changes and even the emergence of new genes and the extinction of existing ones. Here, we provide a general review of recent findings into the genetic basis of human brain evolution, highlight the most notable trends that have emerged and caution against over-interpretation of current data. PMID:18848363

Vallender, Eric J; Mekel-Bobrov, Nitzan; Lahn, Bruce T

2008-10-08

50

Brain evolution and human neuropsychology: the inferential brain hypothesis.  

PubMed

Collaboration between human neuropsychology and comparative neuroscience has generated invaluable contributions to our understanding of human brain evolution and function. Further cross-talk between these disciplines has the potential to continue to revolutionize these fields. Modern neuroimaging methods could be applied in a comparative context, yielding exciting new data with the potential of providing insight into brain evolution. Conversely, incorporating an evolutionary base into the theoretical perspectives from which we approach human neuropsychology could lead to novel hypotheses and testable predictions. In the spirit of these objectives, we present here a new theoretical proposal, the Inferential Brain Hypothesis, whereby the human brain is thought to be characterized by a shift from perceptual processing to inferential computation, particularly within the social realm. This shift is believed to be a driving force for the evolution of the large human cortex. (JINS, 2012, 18, 394-401). PMID:22459075

Koscik, Timothy R; Tranel, Daniel

2012-03-30

51

Three-dimensional assessment of brain tissue morphology  

NASA Astrophysics Data System (ADS)

The microstructure of brain tissues becomes visible using different types of optical microscopy after the tissue sectioning. This preparation procedure introduces stress and strain in the anisotropic and inhomogeneous soft tissue slices, which are several 10 ?m thick. Consequently, the three-dimensional dataset, generated out of the two-dimensional images with lateral submicrometer resolution, needs algorithms to correct the deformations, which can be significant for mellow tissue such as brain segments. The spatial resolution perpendicular to the slices is much worse with respect to the lateral sub-micrometer resolution. Therefore, we propose as complementary method the synchrotron-radiation-based micro computed tomography (SR?CT), which avoids any kind of preparation artifacts due to sectioning and histological processing and yields true micrometer resolution in the three orthogonal directions. The visualization of soft matter by the use of SR?CT, however, is often based on elaborate staining protocols, since the tissue exhibits (almost) the same x-ray absorption as the surrounding medium. Therefore, it is unexpected that human tissue from the pons and the medulla oblongata in phosphate buffer show several features such as the blood vessels and the inferior olivary nucleus without staining. The value of these tomograms lies especially in the precise non-rigid registration of the different sets of histological slices. Applications of this method to larger pieces of brain tissue, such as the human thalamus are planned in the context of stereotactic functional neurosurgery.

Müller, Bert; Germann, Marco; Jeanmonod, Daniel; Morel, Anne

2006-08-01

52

Towards multimodal atlases of the human brain  

PubMed Central

Atlases of the human brain have an important impact on neuroscience. The emergence of ever more sophisticated imaging techniques, brain mapping methods and analytical strategies has the potential to revolutionize the concept of the brain atlas. Atlases can now combine data describing multiple aspects of brain structure or function at different scales from different subjects, yielding a truly integrative and comprehensive description of this organ. These integrative approaches have provided significant impetus for the human brain mapping initiatives, and have important applications in health and disease.

Toga, Arthur W.; Thompson, Paul M.; Mori, Susumu; Amunts, Katrin; Zilles, Karl

2010-01-01

53

Decoding patterns of human brain activity.  

PubMed

Considerable information about mental states can be decoded from noninvasive measures of human brain activity. Analyses of brain activity patterns can reveal what a person is seeing, perceiving, attending to, or remembering. Moreover, multidimensional models can be used to investigate how the brain encodes complex visual scenes or abstract semantic information. Such feats of "brain reading" or "mind reading," though impressive, raise important conceptual, methodological, and ethical issues. What does successful decoding reveal about the cognitive functions performed by a brain region? How should brain signals be spatially selected and mathematically combined to ensure that decoding reflects inherent computations of the brain rather than those performed by the decoder? We highlight recent advances and describe how multivoxel pattern analysis can provide a window into mind-brain relationships with unprecedented specificity, when carefully applied. However, as brain-reading technology advances, issues of neuroethics and mental privacy will be important to consider. PMID:21943172

Tong, Frank; Pratte, Michael S

2011-09-19

54

Increased expression of aquaporin-4 in human traumatic brain injury and brain tumors  

Microsoft Academic Search

Objective: To characterize the expression of aquaporin-4 (AQP4), one of the aquaporins (AQPs), in human brain specimens from patients with traumatic brain injury or brain tumors. Methods: Nineteen human brain specimens were obtained from the patients with traumatic brain injury, brain tumors, benign meningioma or early stage hemorrhagic stroke. MRI or CT imaging was used to assess brain edema. Hematoxylin

HU Hua; YAO Hong-tian; ZHANG Wei-ping; ZHANG Lei; DING Wei; ZHANG Shi-hong; CHEN Zhong; WEI Er-qing

2005-01-01

55

Determining correspondence in 3-D MR brain images using attribute vectors as morphological signatures of voxels.  

PubMed

Finding point correspondence in anatomical images is a key step in shape analysis and deformable registration. This paper proposes an automatic correspondence detection algorithm for intramodality MR brain images of different subjects using wavelet-based attribute vectors (WAVs) defined on every image voxel. The attribute vector (AV) is extracted from the wavelet subimages and reflects the image structure in a large neighborhood around the respective voxel in a multiscale fashion. It plays the role of a morphological signature for each voxel, and our goal is, therefore, to make it distinctive of the respective voxel. Correspondence is then determined from similarities of AVs. By incorporating the prior knowledge of the spatial relationship among voxels, the ability of the proposed algorithm to find anatomical correspondence is further improved. Experiments with MR images of human brains show that the algorithm performs similarly to experts, even for complex cortical structures. PMID:15493695

Xue, Zhong; Shen, Dinggang; Davatzikos, Christos

2004-10-01

56

Human Misato regulates mitochondrial distribution and morphology  

SciTech Connect

Misato of Drosophila melanogaster and Saccharomyces cerevisiae DML1 are conserved proteins having a homologous region with a part of the GTPase family that includes eukaryotic tubulin and prokaryotic FtsZ. We characterized human Misato sharing homology with Misato of D. melanogaster and S. cerevisiae DML1. Tissue distribution of Misato exhibited ubiquitous distribution. Subcellular localization of the protein studied using anti-Misato antibody suggested that it is localized to the mitochondria. Further experiments of fractionating mitochondria revealed that Misato was localized to the outer membrane. The transfection of Misato siRNA led to growth deficiencies compared with control siRNA transfected HeLa cells, and the Misato-depleted HeLa cells showed apoptotic nuclear fragmentation resulting in cell death. After silencing of Misato, the filamentous mitochondrial network disappeared and fragmented mitochondria were observed, indicating human Misato has a role in mitochondrial fusion. To examine the effects of overexpression, COS-7 cells were transfected with cDNA encoding EGFP-Misato. Its overexpression resulted in the formation of perinuclear aggregations of mitochondria in these cells. The Misato-overexpressing cells showed low viability and had no nuclei or a small and structurally unusual ones. These results indicated that human Misato has a role(s) in mitochondrial distribution and morphology and that its unregulated expression leads to cell death.

Kimura, Masashi [Department of Molecular Pathobiochemistry, Division of Disease Control, Gifu University Graduate School of Medicine, Yanagido 1-1, Gifu 501-1194 (Japan)]. E-mail: yo@gifu-u.ac.jp; Okano, Yukio [Department of Molecular Pathobiochemistry, Division of Disease Control, Gifu University Graduate School of Medicine, Yanagido 1-1, Gifu 501-1194 (Japan)

2007-04-15

57

Trigeminal ganglion morphology in human fetus.  

PubMed

The morphology of the trigeminal ganglion in human fetus was investigated by means of the tract-tracing method using the lipophilic dye DiI-C18-(3) (1,1'-double octadecane 3,3,3'3'-tetramethyl indole carbonyl cyanine-perchlorate), hematoxylin-eosin (HE) stain, and three-dimensional computer reconstruction models. The trigeminal ganglion was flat in the dorsoventral direction, and DiI staining revealed that the trigeminal ganglion cells were somatotopically distributed in the ganglion in a way that reflected the mediolateral order of the three branches. Ganglion cells of the ophthalmic nerve were distributed in the anteromedial part of the trigeminal ganglion, those of the mandibular nerve were in the posterolateral part, and those of the maxillary nerve were localized in the intermediate part. DiI labeled both ganglion cells and nerve fibers in the trigeminal ganglion; the ganglion cells varied in size and appeared as round- or oval-shaped, the neurites connected the cell soma, and some bipolar neurons were also observed. The number of embryonic trigeminal ganglion cells did not significantly change with gestational age, but the cell diameter, area, and perimeter significantly increased. The motor root leaves the pons, runs along the sensory root, passes the ventral surface of the ganglion, and finally runs together with the mandibular nerve. The findings reported here elucidate the morphology, development, and somatotopic organization of the trigeminal ganglion and reveal the trigeminal nerve motor root pathway along the trigeminal ganglion and mandibular nerve in the human fetus. PMID:23495217

Wu, Li; Zhang, Haitao; Liao, Libin; Dadihan, Tuerxunjiang; Wang, Xiaolin; Kerem, Gulnisa

2013-03-15

58

ENDOPHENOTYPES IN NORMAL BRAIN MORPHOLOGY AND ALZHEIMER'S DISEASE: A REVIEW  

PubMed Central

Late-onset Alzheimer’s disease is a common complex disorder of old age. Though these types of disorders can be highly heritable, they differ from single-gene (Mendelian) diseases in that their causes are often multifactorial with both genetic and environmental components. Genetic risk factors that have been firmly implicated in the cause are mutations in the amyloid precursor protein (APP), presenilin 1 (PSEN1) and presenilin 2 (PSEN2) genes, which are found in large multi-generational families with an autosomal dominant pattern of disease inheritance, the apolipoprotein E (APOE)?4 allele and the sortilin-related receptor (SORL1) gene. Environmental factors that have been associated with late-onset Alzheimer’s disease include depressive illness, various vascular risk factors, level of education, head trauma and estrogen replacement therapy. This complexity may help explain their high prevalence from an evolutionary perspective, but the etiologic complexity makes identification of disease-related genes much more difficult. The “endophenotype” approach is an alternative method for measuring phenotypic variation that may facilitate the identification of susceptibility genes for complexly inherited traits. The usefulness of endophenotypes in genetic analyses of normal brain morphology and, in particular for Alzheimer’s disease will be reviewed as will the implications of these findings for models of disease causation. Given that the pathways from genotypes to end-stage phenotypes are circuitous at best, identifying endophenotypes more proximal to the effects of genetic variation may expedite the attempts to link genetic variants to disorders.

Reitz, C.; Mayeux, R.

2010-01-01

59

Protein phosphorylation systems in postmortem human brain  

SciTech Connect

Protein phosphorylation systems regulated by cyclic adenosine 3',5'-monophosphate (cyclic AMP), or calcium in conjunction with calmodulin or phospholipid/diacylglycerol, have been studied by phosphorylation in vitro of particulate and soluble fractions from human postmortem brain samples. One-dimensional or two-dimensional gel electrophoretic protein separations were used for analysis. Protein phosphorylation catalyzed by cyclic AMP-dependent protein kinase was found to be highly active in both particulate and soluble preparations throughout the human CNS, with groups of both widely distributed and region-specific substrates being observed in different brain nuclei. Dopamine-innervated parts of the basal ganglia and cerebral cortex contained the phosphoproteins previously observed in rodent basal ganglia. In contrast, calcium/phospholipid-dependent and calcium/calmodulin-dependent protein phosphorylation systems were less prominent in human postmortem brain than in rodent brain, and only a few widely distributed substrates for these protein kinases were found. Protein staining indicated that postmortem proteolysis, particularly of high-molecular-mass proteins, was prominent in deeply located, subcortical regions in the human brain. Our results indicate that it is feasible to use human postmortem brain samples, when obtained under carefully controlled conditions, for qualitative studies on brain protein phosphorylation. Such studies should be of value in studies on human neurological and/or psychiatric disorders.

Walaas, S.I.; Perdahl-Wallace, E.; Winblad, B.; Greengard, P. (Rockefeller Univ., New York, NY (USA))

1989-01-01

60

Morphological and behavioral markers of environmentally induced retardation of brain development: an animal model.  

PubMed

In most neurotoxicological studies morphological assessment focuses on pathological effects, like degenerative changes in neuronal perikarya, axonopathy, demyelination, and glial and endothelial cell reactions. Similarly, the assessment of physiological and behavioral effects center on evident neurological symptoms, like EEG and EMG abnormalities, resting and intention tremor, abnormal gait, and abnormal reflexes. This paper reviews briefly another central nervous system target of harmful environmental agents, which results in behavioral abnormalities without any qualitatively evident neuropathology. This is called microneuronal hypoplasia, a retardation of brain development characterized by a quantitative reduction in the normal population of late-generated, short-axoned neurons in specific brain regions. Correlated descriptive and experimental neurogenetic studies in the rat have established that all the cerebellar granule cells and a very high proportion of hippocampal granule cells are produced postnatally, and that focal, low-dose X-irradiation either of the cerebellum or of the hippocampus after birth selectively interferes with the acquisition of the full complement of granule cells (microneuronal hypoplasia). Subsequent behavioral investigations showed that cerebellar microneuronal hypoplasia results in profound hyperactivity without motor abnormalities, while hippocampal microneuronal hypoplasia results in hyperactivity, as well as attentional and learning deficits. There is much indirect clinical evidence that various harmful environmental agents affecting the pregnant mother and/or the infant lead to such childhood disorders as hyperactivity and attentional and learning disorders. As the developing human brain is more mature at birth than the rat brain, the risk for microneuronal hypoplasia and consequent behavioral disorders may be highest at late stages of fetal development, in prematurely born and small-for-weight infants, and during the early stages of infant development. Recent technological advances in brain imaging techniques make it possible to test this hypothesis and to assess the possible relationship between the degree of retarded brain development and ensuing behavioral disorders. PMID:3319550

Altman, J

1987-10-01

61

Distribution of testican expression in human brain  

Microsoft Academic Search

Testican is a putative extracellular heparan\\/chondroitin sulfate proteoglycan of unknown function that is expressed in a variety of human tissues at widely different levels but is most abundant in the brain. In mice, testican mRNA has been detected only in brain and it is therefore likely to have an important function in the central nervous system. RNA blot analysis reveals

Henry S. Marr; Mohammad A. Basalamah; Thomas W. Bouldin; Andrew W. Duncan; Cora-Jean S. Edgell

2000-01-01

62

Essential Fatty Acids and Human Brain  

Microsoft Academic Search

3 Abstract- The human brain is nearly 60 percent fat. We've learned in recent years that fatty acids are among the most crucial molecules that determine your brain's integrity and ability to perform. Essential fatty acids (EFAs) are required for maintenance of optimal health but they can not synthesized by the body and must be obtained from dietary sources. Clinical

Chia-Yu Chang; Jen-Yin Chen

2009-01-01

63

Transcranial magnetic stimulation and the human brain  

Microsoft Academic Search

Transcranial magnetic stimulation (TMS) is rapidly developing as a powerful, non-invasive tool for studying the human brain. A pulsed magnetic field creates current flow in the brain and can temporarily excite or inhibit specific areas. TMS of motor cortex can produce a muscle twitch or block movement; TMS of occipital cortex can produce visual phosphenes or scotomas. TMS can also

Mark Hallett

2000-01-01

64

Electrophysiological Evaluation of Human Brain Development  

Microsoft Academic Search

The complex development of the human brain during infancy can only be understood by convergent structural, functional, and behavioral measurements. The evaluation of event-related potentials (ERPs) is the most effective current way to look at infant brain function. ERP paradigms can be used to examine the simple transmission of sensory information to the cortex and the discrimination of this information

Terence W. Picton; Margot J. Taylor

2007-01-01

65

Human brain evolution: insights from microarrays  

Microsoft Academic Search

Several recent microarray studies have compared gene-expression patterns n humans, chimpanzees and other non-human primates to identify evolutionary changes that contribute to the distinctive cognitive and behavioural characteristics of humans. These studies support the surprising conclusion that the evolution of the human brain involved an upregulation of gene expression relative to non-human primates, a finding that could be relevant to

Mario Cáceres; Michael C. Oldham; Todd M. Preuss; Daniel H. Geschwind

2004-01-01

66

The scented brain: pheromonal responses in humans.  

PubMed

Using PET, Savic et al., in this issue of Neuron, found a sexually dimorphic neural response to two putative human pheromones. The specific regions activated combined with the pronounced sex difference depict a pheromonal-type brain response in humans. Here, we preview this finding and suggest that human pheromones exist. PMID:11545709

Sobel, N; Brown, W M

2001-08-30

67

Neurotransmitter and Peptide Localization in Human Brain.  

National Technical Information Service (NTIS)

Studies utilizing human brain tissue examined the colocalozation of neurotransmitters using immunocytochemical and in vitro hybridization techniques. Results have shown the coexistance of somatostatin and neuropeptide Y in the hippocampus, and galanin and...

V. Chan-Palay

1990-01-01

68

Organization of the Human Brain.  

ERIC Educational Resources Information Center

|This article reviews the work on patients who have undergone partial or complete brain bisection and addresses the concept of modularity from three different perspectives: (1) structure-function correlations; (2) modular components of cognitive processes; and (3) integration of modular processes. Several brain pictures and diagrams are presented.…

Gazzaniga, Michael S.

1989-01-01

69

Artificial Intelligence and Human Brain Imaging  

Microsoft Academic Search

For many years AI researchers have sought to understand the nature of intelligence primarily by creating artificially intelligent\\u000a computer systems. Studies of human intelligence have had less influence on AI, partly because of the great difficulty in directly\\u000a observing human brain activity. In recent years, new methods for observing brain activity have become available, notably functional\\u000a Magnetic Resonance Imaging (fMRI)

Tom M. Mitchell

2003-01-01

70

A 3D Human Brain Atlas  

Microsoft Academic Search

\\u000a 3D representations of human physiology provide interesting options in the field of education. Understanding the human brain\\u000a seems to be much easier when the anatomical structure is shown in the three-dimensional domain rather than in a 2D or flat\\u000a projection. Seeing how the brain is ’wired’ and how the different regions are connected to form circuits and complex networks\\u000a requires

Sebastian Thelen; Joerg Meyer; Achim Ebert; Hans Hagen

2009-01-01

71

Behavioral Stochastic Resonance within the Human Brain  

NASA Astrophysics Data System (ADS)

We provide the first evidence that stochastic resonance within the human brain can enhance behavioral responses to weak sensory inputs. We asked subjects to adjust handgrip force to a slowly changing, subthreshold gray level signal presented to their right eye. Behavioral responses were optimized by presenting randomly changing gray levels separately to the left eye. The results indicate that observed behavioral stochastic resonance was mediated by neural activity within the human brain where the information from both eyes converges.

Kitajo, Keiichi; Nozaki, Daichi; Ward, Lawrence M.; Yamamoto, Yoshiharu

2003-05-01

72

Neurosteroid metabolism in the human brain  

Microsoft Academic Search

This review summarizes the current knowledge of the biosynthesis of neurosteroids in the human brain, the enzymes mediating these reactions, their localization and the putative effects of neurosteroids. Molecular biological and biochemical studies have now firmly established the presence of the steroidogenic enzymes cytochrome P450 cholesterol side-chain cleavage (P450SCC), aromatase, 5a-reductase, 3a-hydroxysteroid dehydrogenase and 17b-hydroxysteroid dehydrogenase in human brain. The

Birgit Stoffel-Wagner

2001-01-01

73

Functional Coactivation Map of the Human Brain  

PubMed Central

Understanding the interactions among different brain regions is fundamental to our understanding of brain function. Here we describe a complete map of functional connections in the human brain derived by an automatic meta-analysis of 825 neuroimaging articles, representing 3402 experiments. The likelihood of a functional connection between regions was estimated by studying the interdependence of their “activity,” as reported in each experiment, across all experiments. We obtained a dense coactivation map that recovers some fundamental principles of the brain's functional connectivity, such as the symmetric interhemispheric connections, and important functional networks, such as the fronto-parietal attention network, the resting state network and the motor network.

Fox, Peter T.; Paus, Tomas

2008-01-01

74

Interleukin-6 gene (IL-6): a possible role in brain morphology in the healthy adult brain  

PubMed Central

Background Cytokines such as interleukin 6 (IL-6) have been implicated in dual functions in neuropsychiatric disorders. Little is known about the genetic predisposition to neurodegenerative and neuroproliferative properties of cytokine genes. In this study the potential dual role of several IL-6 polymorphisms in brain morphology is investigated. Methodology In a large sample of healthy individuals (N?=?303), associations between genetic variants of IL-6 (rs1800795; rs1800796, rs2069833, rs2069840) and brain volume (gray matter volume) were analyzed using voxel-based morphometry (VBM). Selection of single nucleotide polymorphisms (SNPs) followed a tagging SNP approach (e.g., Stampa algorigthm), yielding a capture 97.08% of the variation in the IL-6 gene using four tagging SNPs. Principal findings/results In a whole-brain analysis, the polymorphism rs1800795 (?174?C/G) showed a strong main effect of genotype (43 CC vs. 150 CG vs. 100 GG; x?=?24, y?=??10, z?=??15; F(2,286)?=?8.54, puncorrected?=?0.0002; pAlphaSim-corrected?=?0.002; cluster size k?=?577) within the right hippocampus head. Homozygous carriers of the G-allele had significantly larger hippocampus gray matter volumes compared to heterozygous subjects. None of the other investigated SNPs showed a significant association with grey matter volume in whole-brain analyses. Conclusions/significance These findings suggest a possible neuroprotective role of the G-allele of the SNP rs1800795 on hippocampal volumes. Studies on the role of this SNP in psychiatric populations and especially in those with an affected hippocampus (e.g., by maltreatment, stress) are warranted.

2012-01-01

75

The human brain: rewired and running hot  

PubMed Central

The past two decades have witnessed tremendous advances in noninvasive and postmortem neuroscientific techniques, advances that have made it possible, for the first time, to compare in detail the organization of the human brain to that of other primates. Studies comparing humans to chimpanzees and other great apes reveal that human brain evolution was not merely a matter of enlargement, but involved changes at all levels of organization that have been examined. These include the cellular and laminar organization of cortical areas; the higher-order organization of the cortex, as reflected in the expansion of association cortex (in absolute terms, as well as relative to primary areas); the distribution of long-distance cortical connections; and hemispheric asymmetry. Additionally, genetic differences between humans and other primates have proven to be more extensive than previously thought, raising the possibility that human brain evolution involved significant modifications of neurophysiology and cerebral energy metabolism.

Preuss, Todd M.

2011-01-01

76

The human brain: rewired and running hot.  

PubMed

The past two decades have witnessed tremendous advances in noninvasive and postmortem neuroscientific techniques, advances that have made it possible, for the first time, to compare in detail the organization of the human brain to that of other primates. Studies comparing humans to chimpanzees and other great apes reveal that human brain evolution was not merely a matter of enlargement, but involved changes at all levels of organization that have been examined. These include the cellular and laminar organization of cortical areas; the higher order organization of the cortex, as reflected in the expansion of association cortex (in absolute terms, as well as relative to primary areas); the distribution of long-distance cortical connections; and hemispheric asymmetry. Additionally, genetic differences between humans and other primates have proven to be more extensive than previously thought, raising the possibility that human brain evolution involved significant modifications of neurophysiology and cerebral energy metabolism. PMID:21599696

Preuss, Todd M

2011-05-01

77

Human brain evolution: insights from microarrays.  

PubMed

Several recent microarray studies have compared gene-expression patterns n humans, chimpanzees and other non-human primates to identify evolutionary changes that contribute to the distinctive cognitive and behavioural characteristics of humans. These studies support the surprising conclusion that the evolution of the human brain involved an upregulation of gene expression relative to non-human primates, a finding that could be relevant to understanding human cerebral physiology and function. These results show how genetic and genomic methods can shed light on the basis of human neural and cognitive specializations, and have important implications for neuroscience, anthropology and medicine. PMID:15520794

Preuss, Todd M; Cáceres, Mario; Oldham, Michael C; Geschwind, Daniel H

2004-11-01

78

The Allen Human Brain Atlas: comprehensive gene expression mapping of the human brain.  

PubMed

The Allen Human Brain Atlas is a freely available multimodal atlas of gene expression and anatomy comprising a comprehensive 'all genes-all structures' array-based dataset of gene expression and complementary in situ hybridization (ISH) gene expression studies targeting selected genes in specific brain regions. Available via the Allen Brain Atlas data portal (www.brain-map.org), the Atlas integrates structure, function, and gene expression data to accelerate basic and clinical research of the human brain in normal and disease states. PMID:23041053

Shen, Elaine H; Overly, Caroline C; Jones, Allan R

2012-10-05

79

Morphology of the Brain of Crayfish, Crabs, and Spiny Lobsters: A Common Nomenclature for Homologous Structures  

Microsoft Academic Search

The morphologies of the cerebral ganglia (brains) of three infraorders of the decapod crustaceans (Astacura-crayfish; Brachyura-crabs; Palinura-spiny lob- sters) are described. A common nomenclature is proposed for homologous nerve roots, brain regions, tracts, com- missures, neuropils, and cell body clusters.

DAVID SANDEMAN; RENATE SANDEMAN; CHARLES DERBY; MANFRED SCHMIDT

80

Noise-induced sensitization of human brain  

NASA Astrophysics Data System (ADS)

In the past decade, it has been recognized that noise can enhance the response of nonlinear systems to weak signals, via a mechanism known as stochastic resonance (SR). Particularly, the concept of SR has generated considerable interest in sensory biology, because it has been shown in several experimental studies that noise can assist neural systems in detecting weak signals which could not be detected in its absence. Recently, we have shown a similar type of noise-induced sensitization of human brain; externally added noise to the brain stem baroreflex centers sensitized their responses in maintaining adequate blood perfusion to the brain itself. Furthermore, the addition of noise has also shown to be useful in compensating for dysfunctions of the baroreflex centers in certain neurological diseases. It is concluded that the statistical physics concept of SR could be useful in sensitizing human brain in health and disease.

Yamamoto, Yoshiharu; Hidaka, Ichiro; Nozaki, Daichi; Iso-O, Noriko; Soma, Rika; Kwak, Shin

2002-11-01

81

Multiple aldehyde reductases of human brain.  

PubMed

Human brain contains four forms of aldehyde reducing enzymes. One major activity, designated AR3, has properties indicating its identity with the NADPH-dependent aldehyde reductase, EC 1.1.1.2. The other major form of human brain enzyme, AR1, which is also NADPH-dependent, reduces both aldehyde and ketone-containing substrates, including vitamin K3 (menadione) and daunorubicin, a cancer chemotherapeutic agent. This enzyme is very sensitive to inhibition by the flavonoids quercitrin and quercetine, and may be analogous to a daunorubicin reductase previously described in liver of other species. One minor form of human brain aldehyde reductase, AR2, demonstrates substrate specificity and inhibitor sensitivity which suggest its similarity to aldose reductases found in lens and other tissues of many species. This enzyme, which can also use NADH as cofactor to some extent, is the most active in reducing the aldehyde derivatives of the biogenic amines. The fourth human brain enzyme ("SSA reductase") differs from the other forms in its ability to use NADH as well as or better than NADPH as cofactor, and in its molecular weight, which is nearly twice that of the other forms. It is quite specific for succinic semialdehyde (SSA) as substrate, and was found to be significantly inhibited only by quercetine and quercitrin. AR3 can also reduce SSA, and both enzymes may contribute to the production of gamma-hydroxybutyric acid in vivo. These results indicate that the human brain aldehyde reductases can play relatively specific physiologic roles. PMID:7424738

Hoffman, P L; Wermuth, B; von Wartburg, J P

1980-01-01

82

The Val66Met polymorphism of the brain-derived neurotrophic factor gene affects age-related brain morphology  

Microsoft Academic Search

We investigated the effects of the brain-derived neurotrophic factor (BDNF) Val66Met polymorphism on age-associated changes of brain morphology in 109 Japanese healthy subjects using MRI with optimized voxel-based morphometry technique. A significant age-related volume reduction was found in the dorsolateral prefrontal cortices (DLPFC), anterior cingulate cortices, and temporal and parietal cortices in all subjects. Further analysis revealed a significantly negative

Kiyotaka Nemoto; Takashi Ohnishi; Takeyuki Mori; Yoshiya Moriguchi; Ryota Hashimoto; Takashi Asada; Hiroshi Kunugi

2006-01-01

83

Sexual dimorphism of the developing human brain  

Microsoft Academic Search

1.1. Sexual dimorphism of human brain anatomy has not been well-studied between 4 and 18 years of age, a time of emerging sex differences in behavior and the sexually specific hormonal changes of adrenarche (the predominantly androgenic augmentation of adrenal cortex function occurring at approximately age 8) and puberty.2.2. To assess sex differences in brain structures during this developmental period

Jay N. Giedd; F. Xavier Castellanos; Jagath C. Rajapakse; A. Catherine Vaituzis; Judith L. Rapoport

1997-01-01

84

Human brain evolution writ large and small.  

PubMed

Human evolution was marked by an extraordinary increase in total brain size relative to body size. While it is certain that increased encephalization is an important factor contributing to the origin of our species-specific cognitive abilities, it is difficult to disentangle which aspects of human neural structure and function are correlated by-products of brain size expansion from those that are specifically related to particular psychological specializations, such as language and enhanced "mentalizing" abilities. In this chapter, we review evidence from allometric scaling studies demonstrating that much of human neocortical organization can be understood as a product of brain enlargement. Defining extra-allometric specializations in humans is often hampered by a severe lack of comparative data from the same neuroanatomical variables across a broad range of primates. When possible, we highlight evidence for features of human neocortical architecture and function that cannot be easily explained as correlates of brain size and, hence, might be more directly associated with the evolution of uniquely human cognitive capacities. PMID:22230630

Sherwood, Chet C; Bauernfeind, Amy L; Bianchi, Serena; Raghanti, Mary Ann; Hof, Patrick R

2012-01-01

85

Imaging the Addicted Human Brain  

PubMed Central

Modern imaging techniques enable researchers to observe drug actions and consequences as they occur and persist in the brains of abusing and addicted individuals. This article presents the five most commonly used techniques, explains how each produces images, and describes how researchers interpret them. The authors give examples of key findings illustrating how each technique has extended and deepened our knowledge of the neurobiological bases of drug abuse and addiction, and they address potential clinical and therapeutic applications.

Fowler, Joanna S.; Volkow, Nora D.; Kassed, Cheryl A.; Chang, Linda

2007-01-01

86

Imaging the addicted human brain.  

PubMed

Modern imaging techniques enable researchers to observe drug actions and consequences as they occur and persist in the brains of abusing and addicted individuals. This article presents the five most commonly used techniques, explains how each produces images, and describes how researchers interpret them. The authors give examples of key findings illustrating how each technique has extended and deepened our knowledge of the neurobiological bases of drug abuse and addiction, and they address potential clinical and therapeutic applications. PMID:17514067

Fowler, Joanna S; Volkow, Nora D; Kassed, Cheryl A; Chang, Linda

2007-04-01

87

Molecular insights into human brain evolution.  

PubMed

Rapidly advancing knowledge of genome structure and sequence enables new means for the analysis of specific DNA changes associated with the differences between the human brain and that of other mammals. Recent studies implicate evolutionary changes in messenger RNA and protein expression levels, as well as DNA changes that alter amino acid sequences. We can anticipate having a systematic catalogue of DNA changes in the lineage leading to humans, but an ongoing challenge will be relating these changes to the anatomical and functional differences between our brain and that of our ancient and more recent ancestors. PMID:16136130

Hill, Robert Sean; Walsh, Christopher A

2005-09-01

88

Population Differences in Brain Morphology and Microstructure among Chinese, Malay, and Indian Neonates  

PubMed Central

We studied a sample of 75 Chinese, 73 Malay, and 29 Indian healthy neonates taking part in a cohort study to examine potential differences in neonatal brain morphology and white matter microstructure as a function of ethnicity using both structural T2-weighted magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). We first examined the differences in global size and morphology of the brain among the three groups. We then constructed the T2-weighted MRI and DTI atlases and employed voxel-based analysis to investigate ethnic differences in morphological shape of the brain from the T2-weighted MRI, and white matter microstructure measured by fractional anisotropy derived from DTI. Compared with Malay neonates, the brains of Indian neonates’ tended to be more elongated in anterior and posterior axis relative to the superior-inferior axis of the brain even though the total brain volume was similar among the three groups. Although most anatomical regions of the brain were similar among Chinese, Malay, and Indian neonates, there were anatomical variations in the spinal-cerebellar and cortical-striatal-thalamic neural circuits among the three populations. The population-related brain regions highlighted in our study are key anatomical substrates associated with sensorimotor functions.

Bai, Jordan; Abdul-Rahman, Muhammad Farid; Rifkin-Graboi, Anne; Chong, Yap-Seng; Kwek, Kenneth; Saw, Seang-Mei; Godfrey, Keith M.; Gluckman, Peter D.; Fortier, Marielle V.; Meaney, Michael J.; Qiu, Anqi

2012-01-01

89

Regional aerobic glycolysis in the human brain  

PubMed Central

Aerobic glycolysis is defined as glucose utilization in excess of that used for oxidative phosphorylation despite sufficient oxygen to completely metabolize glucose to carbon dioxide and water. Aerobic glycolysis is present in the normal human brain at rest and increases locally during increased neuronal activity; yet its many biological functions have received scant attention because of a prevailing energy-centric focus on the role of glucose as substrate for oxidative phosphorylation. As an initial step in redressing this neglect, we measured the regional distribution of aerobic glycolysis with positron emission tomography in 33 neurologically normal young adults at rest. We show that the distribution of aerobic glycolysis in the brain is differentially present in previously well-described functional areas. In particular, aerobic glycolysis is significantly elevated in medial and lateral parietal and prefrontal cortices. In contrast, the cerebellum and medial temporal lobes have levels of aerobic glycolysis significantly below the brain mean. The levels of aerobic glycolysis are not strictly related to the levels of brain energy metabolism. For example, sensory cortices exhibit high metabolic rates for glucose and oxygen consumption but low rates of aerobic glycolysis. These striking regional variations in aerobic glycolysis in the normal human brain provide an opportunity to explore how brain systems differentially use the diverse cell biology of glucose in support of their functional specializations in health and disease.

Vaishnavi, S. Neil; Vlassenko, Andrei G.; Rundle, Melissa M.; Snyder, Abraham Z.; Mintun, Mark A.; Raichle, Marcus E.

2010-01-01

90

Hemispherical map for the human brain cortex  

NASA Astrophysics Data System (ADS)

Understanding the function of the human brain cortex is a primary goal in human brain mapping. Methods to unfold and flatten the cortical surface for visualization and measurement have been described in previous literature; but comparison across multiple subjects is still difficult because of the lack of a standard mapping technique. We describe a new approach that maps each hemisphere of the cortex to a portion of a sphere in a standard way, making comparison of anatomy and function across different subjects possible. Starting with a three-dimensional magnetic resonance image of the brain, the cortex is segmented and represented as a triangle mesh. Defining a cut around the corpus collosum identifies the left and right hemispheres. Together, the two hemispheres are mapped to the complex plane using a conformal mapping technique. A Mobius transformation, which is conformal, is used to transform the points on the complex plane so that a projective transformation maps each brain hemisphere onto a spherical segment comprising a sphere with a cap removed. We determined the best size of the spherical cap by minimizing the relative area distortion between hemispherical maps and original cortical surfaces. The relative area distortion between the hemispherical maps and the original cortical surfaces for fifteen human brains is analyzed.

Tosun, Duygu; Prince, Jerry L.

2001-07-01

91

Simple models of human brain functional networks  

PubMed Central

Human brain functional networks are embedded in anatomical space and have topological properties—small-worldness, modularity, fat-tailed degree distributions—that are comparable to many other complex networks. Although a sophisticated set of measures is available to describe the topology of brain networks, the selection pressures that drive their formation remain largely unknown. Here we consider generative models for the probability of a functional connection (an edge) between two cortical regions (nodes) separated by some Euclidean distance in anatomical space. In particular, we propose a model in which the embedded topology of brain networks emerges from two competing factors: a distance penalty based on the cost of maintaining long-range connections; and a topological term that favors links between regions sharing similar input. We show that, together, these two biologically plausible factors are sufficient to capture an impressive range of topological properties of functional brain networks. Model parameters estimated in one set of functional MRI (fMRI) data on normal volunteers provided a good fit to networks estimated in a second independent sample of fMRI data. Furthermore, slightly detuned model parameters also generated a reasonable simulation of the abnormal properties of brain functional networks in people with schizophrenia. We therefore anticipate that many aspects of brain network organization, in health and disease, may be parsimoniously explained by an economical clustering rule for the probability of functional connectivity between different brain areas.

Vertes, Petra E.; Alexander-Bloch, Aaron F.; Gogtay, Nitin; Giedd, Jay N.; Rapoport, Judith L.; Bullmore, Edward T.

2012-01-01

92

[Molecular genetics of the human brain].  

PubMed

The review discusses the contribution of molecular genetic studies to the understanding of human brain performance and defines three genetic objectives: 1) to reveal structural or functional features of brain genes specific merely to man; 2) to outline the complete spectrum of genes involved in brain activity and their regulation; 3) to search for genes and genetic defects resulting in common mental disorders. The plasticity and great variety of brain functions are shown to be based on the unique diversity of genes actively transcribing in the brain and the molecular mechanisms of various genetic products of the same gene: alternative splicing, "antiparallel" coding, regulation of gene activity by signal DNA sequences. Gene search policies are described for common mental disorders such as schizophrenia, manic-depressive psychosis, Alzheimer's disease. The attempts to map defective genes by "reverse" genetics have proved that there is a genetic heterogeneity of these diseases. The novel directions in the study of the brain molecular genetic apparatus can be examinations of chromosomal behavior in the cells in various brain regions and genome imprinting. PMID:1282409

Rogaev, E I; Iurov, Iu B; Iakovlev, A G

1992-01-01

93

Human intelligence and brain networks  

PubMed Central

Intelligence can be defined as a general mental ability for reasoning, problem solving, and learning. Because of its general nature, intelligence integrates cognitive functions such as perception, attention, memory, language, or planning. On the basis of this definition, intelligence can be reliably measured by standardized tests with obtained scores predicting several broad social outcomes such as educational achievement, job performance, health, and longevity. A detailed understanding of the brain mechanisms underlying this general mental ability could provide significant individual and societal benefits. Structural and functional neuroimaging studies have generally supported a frontoparietal network relevant for intelligence. This same network has also been found to underlie cognitive functions related to perception, short-term memory storage, and language. The distributed nature of this network and its involvement in a wide range of cognitive functions fits well with the integrative nature of intelligence. A new key phase of research is beginning to investigate how functional networks relate to structural networks, with emphasis on how distributed brain areas communicate with each other.

Colom, Roberto; Karama, Sherif; Jung, Rex E.; Haier, Richard J.

2010-01-01

94

Brain mechanisms underlying human communication  

Microsoft Academic Search

Human communication has been described as involving the coding-decoding of a conventional symbol system, which could be supported by parts of the human motor system (i.e. the “mirror neurons system”). However, this view does not explain how these conventions could develop in the first place. Here we target the neglected but crucial issue of how people organize their non-verbal behavior

Matthijs L. Noordzij; Sarah E. Newman-Norlund; Ruiter de Jan Peter; Peter Hagoort; Stephen C. Levinson; Ivan Toni

2009-01-01

95

Tolerances of the Human Brain to Concussion.  

National Technical Information Service (NTIS)

The report reviews the pertinent literature and adds additional evidence indicating that the human brain may be able to tolerate head impact forces in the range of 300 to 400 g's without evidence of concussion or other detectable neurologic sequelae, prov...

J. J. Swearingen

1971-01-01

96

Methods Towards Invasive Human Brain Computer Interfaces  

Microsoft Academic Search

During the last ten years there has been growing interest in the develop- ment of Brain Computer Interfaces (BCIs). The eld has mainly been driven by the needs of completely paralyzed patients to communicate. With a few exceptions, most human BCIs are based on extracranial elec- troencephalography (EEG). However, reported bit rates are still low. One reason for this is

Thomas Navin Lal; Thilo Hinterberger; Guido Widman; Michael Schröder; N. Jeremy Hill; Wolfgang Rosenstiel; Christian Erich Elger; Bernhard Schölkopf; Niels Birbaumer

2004-01-01

97

Methods towards invasive human brain computer interfaces  

Microsoft Academic Search

Abstract During the last ten years there has been growing interest in the development of Brain Computer Interfaces (BCIs). The eld,has mainly been driven by the needs of completely paralyzed patients to communicate. With a few exceptions, most human BCIs are based on extracranial electroencephalography (EEG). However, reported bit rates are still low. One reason for this is the low

T. N. Lal; T. Hinterberger; G. Widman; N. J. Hill; W. Rosenstiel; C. E. Elger; N. Birbaum

2005-01-01

98

Sexual Dimorphism in the Human Brain  

Microsoft Academic Search

In this paper I explpore what is currently known about sexual dimorphisms of the human brain and the developmental processes that produce them. Specifically, I focus on how genetic information brings about changes in the prenatal and neonatal hormonal environment, how that hormonal environment aects developing neural structures, and what the ultimate results of those changes are.

Michael Salib

99

The human parental brain: In vivo neuroimaging  

Microsoft Academic Search

Interacting parenting thoughts and behaviors, supported by key brain circuits, critically shape human infants' current and future behavior. Indeed, the parent–infant relationship provides infants with their first social environment, forming templates for what they can expect from others, how to interact with them and ultimately how they go on to themselves to be parents. This review concentrates on magnetic resonance

James E. Swain

2011-01-01

100

Tracking Hierarchical Processing in Morphological Decomposition with Brain Potentials  

ERIC Educational Resources Information Center

|One important debate in psycholinguistics concerns the nature of morphological decomposition processes in visual word recognition (e.g., darkness = {dark} + {-ness}). One theory claims that these processes arise during orthographic analysis and prior to accessing meaning (Rastle & Davis, 2008), and another argues that these processes arise…

Lavric, Aureliu; Elchlepp, Heike; Rastle, Kathleen

2012-01-01

101

The human brain online: an open resource for advancing brain research.  

PubMed

This community page describes the database and associated Web application that comprise the Allen Human Brain Atlas, an open online resource that integrates genomic and anatomic human brain data. PMID:23300378

Ball, Sara; Gilbert, Terri L; Overly, Caroline C

2012-12-27

102

Computed tomography in migratory disorders of human brain development  

Microsoft Academic Search

Computed tomographic findings in developmental brain anomalies are more easily classified when the system used is based on embryogenesis related to morphology. Analysis of computed tomographic findings in a series of 154 patients with brain anomalies (Chiari malformation not included) revealed that specific examples of abnormalities occurring in major stages of brain development may be recognized by computed tomography. This

R. A. Zimmerman; Larissa T. Bilaniuk; R. I. Grossman

1983-01-01

103

[Evolution of human brain and intelligence].  

PubMed

The biological evolution, including human evolution is mainly driven by environmental changes. Accidental genetic modifications and their innovative results make the successful adaptation possible. As we know the human evolution started 7-8 million years ago in the African savannah, where upright position and bipedalism were significantly advantageous. The main drive of improving manual actions and tool making could be to obtain more food. Our ancestor got more meat due to more successful hunting, resulting in more caloric intake, more protein and essential fatty acid in the meal. The nervous system uses disproportionally high level of energy, so better quality of food was a basic condition for the evolution of huge human brain. The size of human brain was tripled during 3.5 million years, it increased from the average of 450 cm3 of Australopithecinae to the average of 1350 cm3 of Homo sapiens. A genetic change in the system controlling gene expression could happen about 200 000 years ago, which influenced the development of nervous system, the sensorimotor function and learning ability for motor processes. The appearance and stabilisation of FOXP2 gene structure as feature of modern man coincided with the first presence and quick spread of Homo sapiens on the whole Earth. This genetic modification made opportunity for human language, as the basis of abrupt evolution of human intelligence. The brain region being responsible for human language is the left planum temporale, which is much larger in left hemisphere. This shows the most typical human brain asymmetry. In this case the anatomical asymmetry means a clearly defined functional asymmetry as well, where the brain hemispheres act differently. The preference in using hands, the lateralised using of tools resulted in the brain asymmetry, which is the precondition of human language and intelligence. However, it cannot be held anymore, that only humans make tools, because our closest relatives, the chimpanzees are able not only to use, but also to make tools, and they can be taught how to produce quite difficult ones. Some brain characteristics connected to human consciousness and intelligence, like brain asymmetry, the "consciousness" or "theory of mind" based on mirror neurons are surprisingly present in monkeys. Nevertheless, the human intelligence is extremely flexible and different, while the animal intelligence is specialised, producing one thing at high level. Based on recent knowledge the level of intelligence is related anatomically to the number of cortical neurons and physiologically to the speed of conductivity of neural pathways, the latter being dependent on the degree of myelinisation. The improvement of cognitive functions including language is driver by the need of more effective communication requiring less energy, the need of social dominance, the competitive advantages within smaller groups and species or against other species, which improves the opportunity for obtaining food. Better mental skills give also sexual dominance, which is beneficial for stabilising "cleverness" genes. The evolutionary history of human consciousness emphasises its adaptive survival helping nature. The evolution of language was the basic condition of conscious thinking as a qualitative change, which fundamentally differentiate us from all other creatures. PMID:18763477

Lakatos, László; Janka, Zoltán

2008-07-30

104

Distribution of testican expression in human brain.  

PubMed

Testican is a putative extracellular heparan/ chondroitin sulfate proteoglycan of unknown function that is expressed in a variety of human tissues at widely different levels but is most abundant in the brain. In mice, testican mRNA has been detected only in brain and it is therefore likely to have an important function in the central nervous system. RNA blot analysis reveals the relative intensity of testican in various regions of the human brain. Levels of testican message are most pronounced in the thalamus, hippocampus, occipital lobe, nucleus accumbens, temporal lobe, and caudate nucleus, with somewhat lower levels in the cerebral cortex, medulla oblongata, frontal lobe, amygdala, putamen, spinal cord, substantia nigra, and cerebellum. In situ hybridization reveals the cellular distribution of the mRNA within these areas to be highest in neurons and in choroid plexus epithelium, and moderately lower in ependymal cells lining the ventricles and in vascular endothelial cells. Testican mRNA is not detected in oligodendrocytes or in most astrocytes. However, astrocytes in regions of reactive gliosis do express testican mRNA. These findings, along with a cysteine-rich pattern similarity to neurocan, brevican, versican, and other proteoglycans found in brain, suggest that testican may be a part of the specialized extracellular matrix of the brain. PMID:11131125

Marr, H S; Basalamah, M A; Bouldin, T W; Duncan, A W; Edgell, C J

2000-11-01

105

Polyrhythm in the Human Brain  

Microsoft Academic Search

Three complementary methods are used to analyze the dynamics of multivariate EEG data obtained from a human listening to a piece of music. The analysis yields parameters for a data sonification that conserves temporal and frequency relationships as well as wave intensities of the data. Multiple events taking place on different time scales are combined to a polyrhythmic display in

Thomas Hermann; Gerold Baier; Markus Müller

2004-01-01

106

How can viruses influence the neuroinflammation and neurodegeneration in the aged human brain.  

PubMed

Age is one of the key risk factors of several human neurodegenerative disorders such as Alzheimer?s disease and Parkinson?s disease. During aging the immune system of the brain undergoes multiple structural and functional changes. The major immune cells of the brain - microglia and astrocytes - significantly change their morphology and functional state during aging. Similarly, the blood brain barrier (BBB), that is considered to be the iron curtain protecting the brain parenchyma against invasion of the pathogens, can be influenced by aging. This state of altered brain immunity may lead to the increased brain vulnerability to viral infections, primoinfection as well as reactivation. We hypothesize that impairment of the brain immunity and BBB integrity can create the optimal condition for viral infection that can further amplify the neuroinflammation mediated by glial cells and neurodegeneration induced and driven by disease modified proteins. PMID:24020754

Marošová, L; Neradil, P; Zilka, N

2013-01-01

107

Stem cell therapy for human brain disorders.  

PubMed

Transplantation of stem cells or their derivatives, and mobilization of endogenous stem cells in the adult brain, have been proposed as future therapies for various brain disorders such as Parkinson's disease and stroke. In support, recent progress shows that neurons suitable for transplantation can be generated from stem cells in culture, and that the adult brain produces new neurons from its own stem cells in response to injury. However, from a clinical perspective, the development of stem cell-based therapies for brain diseases is still at an early stage. Many basic issues remain to be solved and we need to move forward with caution and avoid scientifically ill-founded trials in patients. We do not know the best stem cell source, and research on embryonic stem cells and stem cells from embryonic or adult brain or from other tissues should therefore be performed in parallel. We need to understand how to control stem cell proliferation and differentiation into specific cell types, induce their integration into neural networks, and optimize the functional recovery in animal models closely resembling the human disease. All these scientific efforts are clearly justified because, for the first time, there is now real hope that we in the future can offer patients with currently intractable diseases effective cell-based treatments to restore brain function. PMID:16221169

Lindvall, Olle; Kokaia, Zaal

2005-11-01

108

Quantitative morphological charateristics of developing neurons of the brain-stem reticular formation  

Microsoft Academic Search

Two types of neurons — reticular (with few branches) and multipolar giant (densely ramified) were distinguished in the brain-stem reticular nuclei of the brain in Golgi preparations from cat fetuses aged 45–55 days and kittens aged 1–5 and 30 days. The quantitative morphological characteristics of these neurons at different stages of development were determined from the dimensions of their bodies,

N. G. Gladkovich; T. A. Leontovich; K. V. Shuleikina

1980-01-01

109

Magnetic source imaging of the human brain  

NASA Astrophysics Data System (ADS)

The importance of neuromagnetic studies in basic research on sensory and cognitive functions is well recognized. Researchers are now exploiting more sophisticated paradigms as well as more sophisticated data analysis techniques to achieve new knowledge about the human brain. Our recent identification of characteristic time constants in human auditory cortex that well predict the behavioral lifetime of human auditory sensory memory, and developments and application of various procedures for the magnetic inverse problem have opened new areas of investigation and advanced the technical capability of MSI. With multi-disciplinary efforts from physicists, neural scientists, psychologists and physiologists, MSI is being established as an important modality for functional images.

Lu, Zhong L.; Williamson, Samuel J.; Kaufman, L.

1993-08-01

110

Correlation of morphologic brain lesions with physiologic alterations and blood-brain barrier impairment in 3-intropropionic acid toxicity in rats  

Microsoft Academic Search

3-Nitropropionic acid (NPA), a toxin which irreversibly inhibits the Krebs cycle enzyme succinate dehydrogenase, causes severe neurologic disease and a specific pattern of morphologic brain damage when given subcutaneously to rats. To determine whether hypotension or hypoxemia were necessary for development of morphologic brain lesions in NPA neurotoxicity, systemic blood pressure and arterial blood gases were measured in NPA-intoxicated rats.

B. F. Hamilton; D. H. Gould

1987-01-01

111

Different developmental rates of selected brain structures in humans.  

PubMed

Various rates of development are characteristic for particular structures of the human central nervous system (CNS). The differences of the maturing brain stem and telencephalon are evident in a routine neuropathological examination. The fetal and postnatal archi- and neocortex also reveals uneven levels of maturation. In order to precisely describe those differences in humans we performed a morphological and morphometric study on the dorsal vagal nucleus of the medulla oblongata, on Ammon's horn and on neocortex from midgestation to the 18th postnatal month. The numerical density of neurones, cell perikarya and nuclear cross-sectional area, and the ratio of nucleus to perikaryon area were measured. The results demonstrate a development-dependent decrease in cell density and progressive differentiation of neurones according to their changing size. They express a process of maturation which differs in rate across the CNS structures examined. PMID:8787214

Dambska, M; Kuchna, I

1996-01-01

112

Human brain disease recreated in mice  

SciTech Connect

In the early 1980s, neurologist Stanley Prusiner suggested that scrapie, an apparently infectious degenerative brain disease of sheep, could be transmitted by prions, infectious particles made just of protein - and containing no nucleic acids. But prion research has come a long way since then. In 1985, the cloning of the gene encoding the prion protein proved that it does in fact exist. And the gene turned out to be widely expressed in the brains of higher organisms, a result suggesting that the prion protein has a normal brain function that can somehow be subverted, leading to brain degeneration. Then studies done during the past 2 years suggested that specific mutations in the prion gene might cause two similar human brain diseases, Gerstmann-Straeussler-Scheinker syndrome (GSS) and Creutzfelt-Jakob disease. Now, Prusiner's group at the University of California, San Francisco, has used genetic engineering techniques to recreate GSS by transplanting the mutated prion gene into mice. Not only will the animal model help neurobiologists answer the many remaining questions about prions and how they work, but it may also shed some light on other neurodegenerative diseases as well.

Marx, J.

1990-12-14

113

Morphological brain differences between adult stutterers and non-stutterers  

PubMed Central

Background The neurophysiological and neuroanatomical foundations of persistent developmental stuttering (PDS) are still a matter of dispute. A main argument is that stutterers show atypical anatomical asymmetries of speech-relevant brain areas, which possibly affect speech fluency. The major aim of this study was to determine whether adults with PDS have anomalous anatomy in cortical speech-language areas. Methods Adults with PDS (n = 10) and controls (n = 10) matched for age, sex, hand preference, and education were studied using high-resolution MRI scans. Using a new variant of the voxel-based morphometry technique (augmented VBM) the brains of stutterers and non-stutterers were compared with respect to white matter (WM) and grey matter (GM) differences. Results We found increased WM volumes in a right-hemispheric network comprising the superior temporal gyrus (including the planum temporale), the inferior frontal gyrus (including the pars triangularis), the precentral gyrus in the vicinity of the face and mouth representation, and the anterior middle frontal gyrus. In addition, we detected a leftward WM asymmetry in the auditory cortex in non-stutterers, while stutterers showed symmetric WM volumes. Conclusions These results provide strong evidence that adults with PDS have anomalous anatomy not only in perisylvian speech and language areas but also in prefrontal and sensorimotor areas. Whether this atypical asymmetry of WM is the cause or the consequence of stuttering is still an unanswered question.

Jancke, Lutz; Hanggi, Jurgen; Steinmetz, Helmuth

2004-01-01

114

Exploring candidate genes for human brain diseases from a brain-specific gene network  

Microsoft Academic Search

It is believed that large numbers of genes are involved in common human brain diseases. Here, we propose a novel computational strategy for simultaneously identifying multiple candidate genes for genetic human brain diseases from a brain-specific gene network-level perspective. By integrating diverse genomic and proteomic datasets based on Bayesian statistical model, we built a large-scale human brain-specific gene network. Based

Bing Liu; Tianzi Jiang; Songde Ma; Huizhi Zhao; Jun Li; Xingpeng Jiang; Jing Zhang

2006-01-01

115

A study of the standard brain in Japanese children: morphological comparison with the MNI template.  

PubMed

Functional magnetic resonance imaging (MRI) studies involve normalization so that the brains of different subjects can be described using the same coordinate system. However, standard brain templates, including the Montreal Neurological Institute (MNI) template that is most frequently used at present, were created based on the brains of Western adults. Because morphological characteristics of the brain differ by race and ethnicity and between adults and children, errors are likely to occur when data from the brains of non-Western individuals are processed using these templates. Therefore, this study was conducted to collect basic data for the creation of a Japanese pediatric standard brain. Participants in this study were 45 healthy children (contributing 65 brain images) between the ages of 6 and 9 years, who had nothing notable in their perinatal and other histories and neurological findings, had normal physical findings and cognitive function, exhibited no behavioral abnormalities, and provided analyzable MR images. 3D-T1-weighted images were obtained using a 1.5-T MRI device, and images from each child were adjusted to the reference image by affine transformation using SPM8. The lengths were measured and compared with those of the MNI template. The Western adult standard brain and the Japanese pediatric standard brain obtained in this study differed greatly in size, particularly along the anteroposterior diameter and in height, suggesting that the correction rates are high, and that errors are likely to occur in the normalization of pediatric brain images. We propose that the use of the Japanese pediatric standard brain created in this study will improve the accuracy of identification of brain regions in functional brain imaging studies involving children. PMID:22669123

Uchiyama, Hitoshi T; Seki, Ayumi; Tanaka, Daisuke; Koeda, Tatsuya; Jcs Group

2012-06-04

116

The Distribution and Morphological Characteristics of Serotonergic Cells in the Brain of Monotremes  

Microsoft Academic Search

The distribution and cellular morphology of serotonergic neurons in the brain of two species of monotremes are described. Three clusters of serotonergic neurons were found: a hypothalamic cluster, a cluster in the rostral brainstem and a cluster in the caudal brainstem. Those in the hypothalamus consisted of two groups, the periventricular hypothalamic organ and the infundibular recess, that were intimately

Paul R. Manger; Heidi M. Fahringer; John D. Pettigrew; Jerome M. Siegel

2002-01-01

117

The effect of neuroendocrine secretion on brain morphology and EEG sleep in patients with eating disorders  

Microsoft Academic Search

Summary Neuroendocrine disturbances [low plasma levels of triiodothyronine (T3), high plasma concentrations of cortisol], morphological brain alterations [enlarged external cerebrospinal fluid (CSF) spaces, dilatation of the ventricles] and altered sleep patterns [fragmented sleep continuity, a reduction of slow wave sleep (SWS) or REM sleep] have been described in patients with anorexia nervosa and bulimia nervosa. The present study investigates to

Christoph Lauer; Wolfgang Schreiber; Mathias Berger; Karl-Martin Pirke; Florian Holsboer; Jiirgen-Christian Krieg

1989-01-01

118

Right Hemisphere Brain Morphology, Attention-Deficit Hyperactivity Disorder (ADHD) Subtype, and Social Comprehension  

Microsoft Academic Search

Social comprehension involves empathy for others' experiences and appropriate responses to nonverbal cues. Previous research using magnetic resonance imaging (MRI) has suggested a relationship between brain morphology and psychiatric syndromes, such as attention-deficit hyperactivity disorder (ADHD), that typically entail social difficulties. The right hemisphere, specifically, has been associated with social skill deficits, and numerous studies have also associated ADHD with

Scott R. Miller; Carlin J. Miller; Juliana S. Bloom; George W. Hynd; Jason G. Craggs

2006-01-01

119

Determination of manganese in human brain samples  

Microsoft Academic Search

A method is presented for the determination of manganese (Mn) in human tissue samples (especially brain) by graphite furnace atomic absorption spectrophotometry (GFAAS). After complete digestion by a mixture of concentrated nitric acid (HNO3)\\/concentrated perchloric acid (HClO4) (50:50, v\\/v), the samples are assayed on a Perkin-Elmer 5100 PC apparatus, equipped with transversal graphite tubes and a Mn-specific hollow cathode lamp.

A. Tracqui; J. Tayot; P. Kintz; G. Alves; M. A. Bosque; P. Mangin

1995-01-01

120

Imaging Monoamine Oxidase in the Human Brain  

SciTech Connect

Positron emission tomography (PET) studies mapping monoamine oxidase in the human brain have been used to measure the turnover rate for MAO B; to determine the minimum effective dose of a new MAO inhibitor drug lazabemide and to document MAO inhibition by cigarette smoke. These studies illustrate the power of PET and radiotracer chemistry to measure normal biochemical processes and to provide information on the effect of drug exposure on specific molecular targets.

Fowler, J. S.; Volkow, N. D.; Wang, G-J.; Logan, Jean

1999-11-10

121

Morphology, language and the brain: the decompositional substrate for language comprehension  

Microsoft Academic Search

This paper outlines a neurocognitive approach to human language, focusing on inflectional morphology and grammatical function in English. Taking as a starting point the selective deficits for regular inflectional morphology of a group of non-fluent patients with left hemisphere damage, we argue for a core decompositional network linking left inferior frontal cortex with superior and middle temporal cortex, connected via

William D. Marslen-Wilson; Lorraine K. Tyler

2007-01-01

122

Measures of brain morphology and infarction in the framingham heart study: establishing what is normal  

Microsoft Academic Search

Numerous anatomical and brain imaging studies find substantial differences in brain structure between men and women across the span of human aging. The ability to extend the results of many of these studies to the general population is limited, however, due to the generally small sample size and restrictive health criteria of these studies. Moreover, little attention has been paid

Charles DeCarli; Joseph Massaro; Danielle Harvey; John Hald; Mats Tullberg; Rhoda Au; Alexa Beiser; Ralph D’Agostino; Philip A. Wolf

2005-01-01

123

Molecular evolution of microcephalin, a gene determining human brain size  

Microsoft Academic Search

Microcephalin gene is one of the major players in regulating human brain development. It was reported that truncated mutations in this gene can cause primary microcephaly in humans with a brain size comparable with that of early hominids. We studied the molecular evolution of microcephalin by sequencing the coding region of microcephalin gene in humans and 12 representative non-human primate

Yin-qiu Wang; Bing Su

2004-01-01

124

Synergetic brain model for human-like motion patterns recognition  

Microsoft Academic Search

The ability of human brain in making decisions based on the available information stored in the memory and the information provided through cognitive process are the motivations of simulating human intelligence. This paper presents a brain model able to recognize biological behavioral patterns of human locomotion using synergetic approach. Two human-like motion patterns are studied here: slow and fast walking

I. Za'balawi; Loo Chu Kiong; Wong Eng Kiong

2010-01-01

125

Human blood-brain barrier leptin receptor. Binding and endocytosis in isolated human brain microvessels.  

PubMed Central

The peripheral production of leptin by adipose tissue and its putative effect as a signal of satiety in the central nervous system suggest that leptin gains access to the regions of the brain regulating energy balance by crossing the brain capillary endothelium, which constitutes the blood-brain barrier in vivo. The present experiments characterize the binding and internalization of mouse recombinant leptin in isolated human brain capillaries, an in vitro model of the human blood-brain barrier. Incubation of 125I-leptin with isolated human brain capillaries resulted in temperature-dependent binding: at 37 degrees C, approximately 65% of radiolabeled leptin was bound per milligram of capillary protein. Two-thirds of the bound radioactivity was resistant to removal by acid wash, demonstrating endocytosis of 125I-leptin into capillary cells. At 4 degrees C, binding to isolated capillaries was reduced to approximately 23%/mg of protein, the majority of which was acid wash resistant. Binding of 125I-leptin to brain capillary endothelial plasma membranes was saturable, described by a two-site binding model with a high-affinity dissociation constant of 5.1+/-2.8 nM and maximal binding capacity of 0.34+/-0.16 pmol/mg of membrane protein. Addition of porcine insulin or insulin-like growth factor at a final concentration of 100 nM had a negligible effect on leptin binding. These results provide evidence for a leptin receptor that mediates saturable, specific, temperature-dependent binding and endocytosis of leptin at the human blood-brain barrier.

Golden, P L; Maccagnan, T J; Pardridge, W M

1997-01-01

126

Morphological analysis of in vitro human hair growth  

Microsoft Academic Search

The histological and ultrastructural aspect of normal human hair follicles maintained ex vivo for 12 days was evaluated. Anagen hair follicles, dissected free of contaminating connective tissue, were maintained for up to 12 days in a serum-free medium. Macroscopic observations revealed continued viability for 12 days, at which time some follicles involuted in a manner morphologically similar to catagen. Increased

D. J. Tobin; N. Mandir; R. Dover

1993-01-01

127

DNA Methylation Signatures within the Human Brain  

PubMed Central

DNA methylation is a heritable modification of genomic DNA central to development, imprinting, transcriptional regulation, chromatin structure, and overall genomic stability. Aberrant DNA methylation of individual genes is a hallmark of cancer and has been shown to play an important role in neurological disorders such as Rett syndrome. Here, we asked whether normal DNA methylation might distinguish individual brain regions. We determined the quantitative DNA methylation levels of 1,505 CpG sites representing 807 genes with diverse functions, including proliferation and differentiation, previously shown to be implicated in human cancer. We initially analyzed 76 brain samples representing cerebral cortex (n=35), cerebellum (n=34), and pons (n=7), along with liver samples (n=3) from 43 individuals. Unsupervised hierarchical analysis showed clustering of 33 of 35 cerebra distinct from the clustering of 33 of 34 cerebella, 7 of 7 pons, and all 3 livers. By use of comparative marker selection and permutation testing, 156 loci representing 118 genes showed statistically significant differences—a ?17% absolute change in DNA methylation (P<.004)—among brain regions. These results were validated for all six genes tested in a replicate set of 57 samples. Our data suggest that DNA methylation signatures distinguish brain regions and may help account for region-specific functional specialization.

Ladd-Acosta, Christine; Pevsner, Jonathan; Sabunciyan, Sarven; Yolken, Robert H.; Webster, Maree J.; Dinkins, Tiffany; Callinan, Pauline A.; Fan, Jian-Bing; Potash, James B.; Feinberg, Andrew P.

2007-01-01

128

Perfusion harmonic imaging of the human brain  

NASA Astrophysics Data System (ADS)

The fast visualisation of cerebral microcirculation supports diagnosis of acute cerebrovascular diseases. However, the commonly used CT/MRI-based methods are time consuming and, moreover, costly. Therefore we propose an alternative approach to brain perfusion imaging by means of ultrasonography. In spite of the low signal/noise-ratio of transcranial ultrasound and the high impedance of the skull, flow images of cerebral blood flow can be derived by capturing the kinetics of appropriate contrast agents by harmonic ultrasound image sequences. In this paper we propose three different methods for human brain perfusion imaging, each of which yielding flow images indicating the status of the patient's cerebral microcirculation by visualising local flow parameters. Bolus harmonic imaging (BHI) displays the flow kinetics of bolus injections, while replenishment (RHI) and diminution harmonic imaging (DHI) compute flow characteristics from contrast agent continuous infusions. RHI measures the contrast agents kinetics in the influx phase and DHI displays the diminution kinetics of the contrast agent acquired from the decay phase. In clinical studies, BHI- and RHI-parameter images were found to represent comprehensive and reproducible distributions of physiological cerebral blood flow. For DHI it is shown, that bubble destruction and hence perfusion phenomena principally can be displayed. Generally, perfusion harmonic imaging enables reliable and fast bedside imaging of human brain perfusion. Due to its cost efficiency it complements cerebrovascular diagnostics by established CT/MRI-based methods.

Metzler, Volker H.; Seidel, Guenter; Wiesmann, Martin; Meyer, Karsten; Aach, Til

2003-05-01

129

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

National Technical Information Service (NTIS)

The US Decade of the Brain offers scientists throughout the Federal Government a unique opportunity to advance and apply scientific knowledge about the brain and nervous system. During the next 10 years, scientists hope to maximize human potential through...

1991-01-01

130

Influence of curvature on the morphology of brain microvascular endothelial cells  

NASA Astrophysics Data System (ADS)

There are hundreds or thousands of endothelial cells around the perimeter of a single artery or vein, and hence an individual cell experiences little curvature. In contrast, a single endothelial cell may wrap around itself to form the lumen of a brain capillary. Curvature plays a key role in many biological, chemical and physical processes, however, its role in dictating the morphology and polarization of brain capillary endothelial cells has not been investigated. We hypothesize that curvature and shear flow play a key role in determining the structure and function of the blood-brain barrier (BBB). We have developed the ``rod'' assay to study the influence of curvature on the morphology of confluent monolayers of endothelial cells. In this assay cells are plated onto glass rods pulled down to the desired diameter in the range from 5 -- 500 ?m and coated with collagen. We show that curvature has a significant influence on the morphology of endothelial cells and may have an important role in blood-brain barrier function.

Ye, Mao; Yang, Zhen; Wong, Andrew; Searson, Peter

2013-03-01

131

Mathematical logic in the human brain: semantics.  

PubMed

As a higher cognitive function in humans, mathematics is supported by parietal and prefrontal brain regions. Here, we give an integrative account of the role of the different brain systems in processing the semantics of mathematical logic from the perspective of macroscopic polysynaptic networks. By comparing algebraic and arithmetic expressions of identical underlying structure, we show how the different subparts of a fronto-parietal network are modulated by the semantic domain, over which the mathematical formulae are interpreted. Within this network, the prefrontal cortex represents a system that hosts three major components, namely, control, arithmetic-logic, and short-term memory. This prefrontal system operates on data fed to it by two other systems: a premotor-parietal top-down system that updates and transforms (external) data into an internal format, and a hippocampal bottom-up system that either detects novel information or serves as an access device to memory for previously acquired knowledge. PMID:23301101

Friedrich, Roland M; Friederici, Angela D

2013-01-03

132

A database generator for human brain imaging.  

PubMed

Sharing scientific data containing complex information requires new concepts and new technology. NEUROGENERATOR is a database generator for the neuroimaging community. A database generator is a database that generates new databases. The scientists submit raw PET and fMRI data to NEUROGENERATOR, which then processes the data in a uniform way to create databases of homogeneous data suitable for data sharing, met-analysis and modelling the human brain at the systems level. These databases are then distributed to the scientists. PMID:11576652

Roland, P; Svensson, G; Lindeberg, T; Risch, T; Baumann, P; Dehmel, A; Frederiksson, J; Halldorson, H; Forsberg, L; Young, J; Zilles, K

2001-10-01

133

Determination of manganese in human brain samples.  

PubMed

A method is presented for the determination of manganese (Mn) in human tissue samples (especially brain) by graphite furnace atomic absorption spectrophometry (GFAAS). After complete digestion by a mixture of concentrated nitric acid (HNO3)/concentrated perchloric acid (HClO4) (50:50, v/v), the samples are assayed on a Perkin-Elmer 5100 PC apparatus, equipped with transversal graphite tubes and a Mn-specific hollow cathode lamp. The furnace conditions are as follows (for each step: temperature (degree C)/ramp (s)/duration (s)) dry 120/1/40; char 1200/5/10; atomization 2250/0/4; pyrolysis 2400/1/1. Zeeman correction is employed. The method is linear over the range 0.05 to 5.00 micrograms/g wet tissue, and the limit of detection for Mn is about 0.01 microgram/g wet tissue. This simple and rapid method may be of value for the post-mortem assessment of Mn accumulation in brain structures due to occupational or iatrogenic exposure. An application is presented in which elevated levels of Mn were determined in the brain samples of a 63-year-old female deceased after long-term total parenteral nutrition involving Mn supplementation. PMID:8566922

Tracqui, A; Tayot, J; Kintz, P; Alves, G; Bosque, M A; Mangin, P

1995-12-29

134

Fast Optical Imaging of Human Brain Function  

PubMed Central

Great advancements in brain imaging during the last few decades have opened a large number of new possibilities for neuroscientists. The most dominant methodologies (electrophysiological and magnetic resonance-based methods) emphasize temporal and spatial information, respectively. However, theorizing about brain function has recently emphasized the importance of rapid (within 100?ms or so) interactions between different elements of complex neuronal networks. Fast optical imaging, and in particular the event-related optical signal (EROS, a technology that has emerged over the last 15?years) may provide descriptions of localized (to sub-cm level) brain activity with a temporal resolution of less than 100?ms. The main limitations of EROS are its limited penetration, which allows us to image cortical structures not deeper than 3?cm from the surface of the head, and its low signal-to-noise ratio. Advantages include the fact that EROS is compatible with most other imaging methods, including electrophysiological, magnetic resonance, and trans-cranial magnetic stimulation techniques, with which can be recorded concurrently. In this paper we present a summary of the research that has been conducted so far on fast optical imaging, including evidence for the possibility of recording neuronal signals with this method, the properties of the signals, and various examples of applications to the study of human cognitive neuroscience. Extant issues, controversies, and possible future developments are also discussed.

Gratton, Gabriele; Fabiani, Monica

2010-01-01

135

[Lung cancer metastases to the brain: clinical and morphological prognostic factors].  

PubMed

Brain metastases (BM) are the most frequent intracranial SOL and extremely heterogeneous group of tumours from morphological point of view. Nevertheless, studies devoted to BM up to now paid little attention to the histogenesis of the primary tumour. Lung carcinoma is the most common source of BM; morpologically this is a very heterogeneous group of tumors, and they demostrate different clinical pathway and outcome. The aim of present study was to evaluate clinical and morphological prognostic factors in 126 patients with lung carcinoma metastases to the brain, operated in 2004-2010 at Burdenko Neurosurgical Institute. Statistical analysis demonstrated that age, gender, amount and location of BM, primary operation and even histological tumour type were not significant prognostic factors, meanwhile absence of extracranial metastases and Karnofsky index above 70 were significant factors of the favorable prognosis. PMID:23659117

Rotin, D L; Paklina, O V; Kobiakov, G L; Shishkina, L V; Kravchenko, É V; Stepanian, M A

2013-01-01

136

Evaluating the microstructure of human brain tissues using synchrotron radiation-based micro-computed tomography  

NASA Astrophysics Data System (ADS)

Minimally invasive deep brain neurosurgical interventions require a profound knowledge of the morphology of the human brain. Generic brain atlases are based on histology including multiple preparation steps during the sectioning and staining. In order to correct the distortions induced in the anisotropic, inhomogeneous soft matter and therefore improve the accuracy of brain atlases, a non-destructive 3D imaging technique with the required spatial and density resolution is of great significance. Micro computed tomography provides true micrometer resolution. The application to post mortem human brain, however, is questionable because the differences of the components concerning X-ray absorption are weak. Therefore, magnetic resonance tomography has become the method of choice for three-dimensional imaging of human brain. Because the spatial resolution of this method is limited, an alternative has to be found for the three-dimensional imaging of cellular microstructures within the brain. Therefore, the present study relies on the synchrotron radiationbased micro computed tomography in the recently developed grating-based phase contrast mode. Using data acquired at the beamline ID 19 (ESRF, Grenoble, France) we demonstrate that grating-based tomography yields premium images of human thalamus, which can be used for the correction of histological distortions by 3D non-rigid registration.

Schulz, Georg; Morel, Anne; Imholz, Martha S.; Deyhle, Hans; Weitkamp, Timm; Zanette, Irene; Pfeiffer, Franz; David, Christian; Müller-Gerbl, Magdalena; Müller, Bert

2010-08-01

137

Comorbid substance abuse and brain morphology in recent-onset psychosis  

Microsoft Academic Search

The aim of the presented study was to compare schizophrenia and schizoaffective patients early in the course of the disease\\u000a with and without comorbid substance abuse disorder (SUD vs. NSUD) with regard to brain morphology. In a prospective design\\u000a 41 patients (20 SUD vs. 21 NSUD) diagnosed as recent-onset schizophrenia or schizoaffective disorder consecutively admitted\\u000a to hospital received standardized psychopathological

Thomas Wobrock; Helmut Sittinger; Bernd Behrendt; Roberto D’Amelio; Peter Falkai

2009-01-01

138

Bioprocessing of human glioblastoma brain cancer tissue.  

PubMed

Solid cancer tumors are thought to arise from aberrant stem cell populations, called cancer stem cells (CSCs). Hence, the development of effective cancer therapies may rely on developing methods that specifically target these cells. However, the scarcity of CSCs in vivo represents a major impediment to such research, as there is an insufficient supply for basic biochemical and genetic analyses. It is therefore necessary to develop methods to expand reproducibly CSC tissue in vitro in a controlled environment. To date, we have developed bioreactor protocols for the suspension culture of an aggressive and deadly type of brain cancer called glioblastoma multiforme (GBM). Human GBM-derived cells achieved a maximum cell density of 2.4 x 10(6) cells/mL after 24 days under high shear conditions in batch culture conditions. In comparison, fed-batch cultures achieved 4.5 x 10(6) cells/mL after 32 days. Characterization of bioreactor-expanded cells using both flow cytometry and a differentiation assay indicated that bioreactor-generated human GBM-derived cells have similar characteristics to the initial cell population and achieve >90% CD133 expression. Additionally, genomic characterization indicated that a very small number of key genes were differentially expressed in the bioreactor-expanded GBM-derived cells, thereby conserving the basic nature of the brain cancer tissue in the cell expansion process. PMID:20021271

Panchalingam, Krishna M; Paramchuk, Wendy J; Chiang, Chun-Yi Katherine; Shah, Nameeta; Madan, Anup; Hood, Leroy; Foltz, Greg; Behie, Leo A

2010-04-01

139

Human-induced morphological shifts in an island lizard  

PubMed Central

Understanding the evolutionary consequences of anthropogenic change is an emerging topic in evolutionary biology. While highly sensitive species may go extinct in response to anthropogenic habitat alteration, those with broader environmental tolerances may persist and adapt to the changes. Here, we use morphological data from the brown anole (Anolis sagrei), a lizard species that lives in both natural and human-disturbed habitats, to examine the impact of anthropogenic habitat alteration. We find populations inhabiting disturbed habitats were significantly larger in snout-vent length, hindspan, and mass and provide evidence that the observed divergence in hindspan is driven by human-induced changes in habitat structure. Populations were found to be genetically distinct among islands but are not genetically differentiated between habitat types on islands. Thus, the observed pattern of intra-island morphological differences cannot be explained by separate founding populations. Rather, our results are consistent with morphological differences between habitats having arisen in situ on each island. Results underscore the significant impact anthropogenic change may have on evolutionary trajectories of populations that persist in human-altered habitats.

Marnocha, Erin; Pollinger, John; Smith, Thomas B

2011-01-01

140

Spatio-temporal transcriptome of the human brain  

Microsoft Academic Search

Brain development and function depend on the precise regulation of gene expression. However, our understanding of the complexity and dynamics of the transcriptome of the human brain is incomplete. Here we report the generation and analysis of exon-level transcriptome and associated genotyping data, representing males and females of different ethnicities, from multiple brain regions and neocortical areas of developing and

Hyo Jung Kang; Yuka Imamura Kawasawa; Feng Cheng; Ying Zhu; Xuming Xu; Mingfeng Li; André M. M. Sousa; Mihovil Pletikos; Kyle A. Meyer; Goran Sedmak; Tobias Guennel; Yurae Shin; Matthew B. Johnson; Zeljka Krsnik; Simone Mayer; Sofia Fertuzinhos; Sheila Umlauf; Steven N. Lisgo; Alexander Vortmeyer; Daniel R. Weinberger; Shrikant Mane; Thomas M. Hyde; Anita Huttner; Mark Reimers; Joel E. Kleinman; Nenad Sestan

2011-01-01

141

Changes in glycoprotein carbohydrate content in the aging human brain  

Microsoft Academic Search

There is no significant change in the concentration, per gram of fresh tissue, of the total carbohydrate associated with brain glycoproteins as the human brain ages from 25 to 85 years. Nevertheless, notable shifts in the concentration of varied types of oligosaccharides do occur. The concentration and percentage of total glycopeptide-carbohydrate recovered from the whole brain represented by the N-glycosidically

Eric G. Brunngraber; Joseph C. Webster

1986-01-01

142

Moment-to-moment brain signal variability: a next frontier in human brain mapping?  

PubMed

Neuroscientists have long observed that brain activity is naturally variable from moment-to-moment, but neuroimaging research has largely ignored the potential importance of this phenomenon. An emerging research focus on within-person brain signal variability is providing novel insights, and offering highly predictive, complementary, and even orthogonal views of brain function in relation to human lifespan development, cognitive performance, and various clinical conditions. As a result, brain signal variability is evolving as a bona fide signal of interest, and should no longer be dismissed as meaningless noise when mapping the human brain. PMID:23458776

Garrett, Douglas D; Samanez-Larkin, Gregory R; MacDonald, Stuart W S; Lindenberger, Ulman; McIntosh, Anthony R; Grady, Cheryl L

2013-03-01

143

Brain Prostheses as a Dynamic System (Immortalizing the Human Brain?)  

Microsoft Academic Search

Interest in development of brain prostheses, which might be proposed to recover mental functions lost due to neuron-degenerative disease or trauma, requires new methods in molecular engineering and nanotechnology to build artificial brain tissues. We develop a Dynamic Core model to analyze complexity of damaged biological neural network as well as transition and recovery of the system functionality due to

Vadim Astakhov; Tamara Astakhova

2007-01-01

144

Brain activity and human unilateral chewing: an FMRI study.  

PubMed

Brain mechanisms underlying mastication have been studied in non-human mammals but less so in humans. We used functional magnetic resonance imaging (fMRI) to evaluate brain activity in humans during gum chewing. Chewing was associated with activations in the cerebellum, motor cortex and caudate, cingulate, and brainstem. We also divided the 25-second chew-blocks into 5 segments of equal 5-second durations and evaluated activations within and between each of the 5 segments. This analysis revealed activation clusters unique to the initial segment, which may indicate brain regions involved with initiating chewing. Several clusters were uniquely activated during the last segment as well, which may represent brain regions involved with anticipatory or motor events associated with the end of the chew-block. In conclusion, this study provided evidence for specific brain areas associated with chewing in humans and demonstrated that brain activation patterns may dynamically change over the course of chewing sequences. PMID:23103631

Quintero, A; Ichesco, E; Myers, C; Schutt, R; Gerstner, G E

2012-10-26

145

Localization of copper and copper transporters in the human brain.  

PubMed

Disturbances in brain copper result in rare and severe neurological disorders and may play a role in the pathogenesis and progression of multiple neurodegenerative diseases. Our current understanding of mammalian brain copper transport is based on model systems outside the central nervous system and no data are available regarding copper transport systems in the human brain. To address this deficit, we quantified regional copper concentrations and examined the distribution and cellular localization of the copper transport proteins Copper transporter 1, Atox1, ATP7A, and ATP7B in multiple regions of the human brain using inductively coupled plasma-mass spectrometry, Western blot and immunohistochemistry. We identified significant relationships between copper transporter levels and brain copper concentrations, supporting a role for these proteins in copper transport in the human brain. Interestingly, the substantia nigra contained twice as much copper than that in other brain regions, suggesting an important role for copper in this brain region. Furthermore, ATP7A levels were significantly greater in the cerebellum, compared with other brain regions, supporting an important role for ATP7A in cerebellar neuronal health. This study provides novel data regarding copper regulation in the human brain, critical to understand the mechanisms by which brain copper levels can be altered, leading to neurological disease. PMID:23076575

Davies, Katherine M; Hare, Dominic J; Cottam, Veronica; Chen, Nicholas; Hilgers, Leon; Halliday, Glenda; Mercer, Julian F B; Double, Kay L

2013-01-01

146

Spread of epileptic activity in human brain  

NASA Astrophysics Data System (ADS)

For many patients with medically refractory epilepsy surgical resection of the site of seizure onset (epileptic focus) offers the best hope for cure. Determination of the nature of seizure propagation should lead to improved methods for locating the epileptic focus (and hence reduce patient morbidity) and possibly to new treatment modalities directed at blocking seizure spread. Theoretical studies of neural networks emphasize the role of traveling waves for the propagation of activity. However, the nature of seizure propagation in human brain remains poorly characterized. The spread of epileptic activity in patients undergoing presurgical evaluation for epilepsy surgery was measured by placing subdural grids of electrodes (interelectrode spacings of 3-10 mm) over the frontal and temporal lobes. The exact location of each electrode relative to the surface of the brain was determined using 3--D MRI imaging techniques. Thus it is possible to monitor the spread of epileptic activity in both space and time. The observations are discussed in light of models for seizure propagation.

Milton, John

1997-03-01

147

Maximizing Human Potential. Decade of the Brain 1990-2000.  

National Technical Information Service (NTIS)

The brain is the most sensitive and complicated part of the human body; it is the seat of intelligence, interpreter of senses and controller of movement. Viewed as mysterious and incomprehensible in the past, the human brain is at last yielding up its sec...

1991-01-01

148

Gene regulation and DNA damage in the ageing human brain  

Microsoft Academic Search

The ageing of the human brain is a cause of cognitive decline in the elderly and the major risk factor for Alzheimer's disease. The time in life when brain ageing begins is undefined. Here we show that transcriptional profiling of the human frontal cortex from individuals ranging from 26 to 106 years of age defines a set of genes with

Tao Lu; Ying Pan; Shyan-Yuan Kao; Cheng Li; Isaac Kohane; Jennifer Chan; Bruce A. Yankner

2004-01-01

149

The adult human brain in preclinical drug development  

Microsoft Academic Search

Neurodegenerative disorders are caused by the death and dysfunction of brain cells, but despite a huge worldwide effort, no neuroprotective treatments that slow cell death currently exist. The failure of translation from animal models to humans in the clinic is due to many factors including species differences, human brain complexity, age, patient variability and disease-specific phenotypes. Additional methods are therefore

Mike Dragunow

2008-01-01

150

Magnetic resonance imaging mapping of brain function. Human visual cortex  

Microsoft Academic Search

Magnetic resonance imaging (MRI) studies of human brain activity are described. Task-induced changes in brain cognitive state were measured using high-speed MRI techniques sensitive to changes in cerebral blood volume (CBV), blood flow (CBF), and blood oxygenation. These techniques were used to generate the first functional MRI maps of human task activation, by using a visual stimulus paradigm. The methodology

J. W. Belliveau; K. K. Kwong; D. N. Kennedy; J. R. Baker; C. E. Stern; R. Benson; D. A. Chesler; R. M. Weisskoff; M. S. Cohen; R. B. Tootell; P. T. Fox; T. J. Brady

1992-01-01

151

Subclinical changes in brain morphology following cardiac operations as reflected by computed tomographic scans of the brain.  

PubMed

Effects of cardiopulmonary bypass (CPB) and hypothermic circulatory arrest on brain morphology were evaluated by computed tomography (CT). Of 57 children undergoing cardiac operations, 45 (4.5 +/- 2.8 years of age) were operated upon with the use of CPB with high-flow, mildly hypothermic perfusions. Twenty-seven of them were perfused with bubble oxygenators and 18 with membrane oxygenators. In the bubble oxygenator group, all 14 with 20 mu filters in the arterial line showed no postoperative CT changes, whereas four of 13 (31%) with 40 mu filters or without filters showed decreases in brain mass on CT scans. Three of these four patients underwent perfusion for more than 80 minutes. There were no CT changes in the membrane oxygenator group. Twelve infants (10.4 +/- 4.5 months of age) were operated upon with the aid of deep hypothermia and circulatory arrest (core temperature below 20 degrees C). Ten of 12 who had circulatory arrest for less than 60 minutes showed no CT changes, but two infants who had circulatory arrest for more than 60 minutes showed changes similar to those described above. All six children with CT changes had no clinical manifestation of the brain damage, and their CT abnormalities recovered within 6 to 11 months after operation. The specific cause of these changes remains undetermined, but microemboli or hypoxia during operation could be implicated. PMID:7464200

Muraoka, R; Yokota, M; Aoshima, M; Kyoku, I; Nomoto, S; Kobayashi, A; Nakano, H; Ueda, K; Saito, A; Hojo, H

1981-03-01

152

Brain Morphology and Cerebrovascular Risk in Mild Cognitive Impairment and Dementia: SCOBHI-P study  

PubMed Central

Objective To investigate associations between MRI brain morphology, cerebrovascular risk (VR), clinical diagnosis and cognition among elders living in urban Shanghai. Design Cross-sectional study. Setting Memory Disorders Clinic and community normal control (NC) subject recruitment. Participants Ninety-six older subjects, 32 with normal cognition, 30 with amnestic MCI (aMCI) and 34 with dementia. Main outcome measures Each subject received medical history, neurological/physical exams, neuropsychological evaluations, brain MRI and apolipoprotein E-?4 (APOE -?4) genotype test. MRI volumes were assessed using a semi-automatic method. Results Brain volume (BV) was significantly smaller in the demented compared with NC (p < 0.001) or aMCI (p = 0.043). Hippocampal volume (HV) was lower, and white matter hyperintensity volume (WMH) was higher, in aMCI (HV: p = 0.028; WMH: p = 0.041) and dementia (HV: p < 0.001; WMH: p = 0.002) compared with NC. APOE -?4 presence was significantly associated with reduced HV (p = 0.02). Systolic blood pressure was positively associated with VR score (p = 0.037); diastolic blood pressure (p = 0.021) and VR score (p = 0.036) were both positively associated with WMH. WMH (p = 0.029) and VR (p = 0.031) were both higher among the demented than NC. Conclusion MRI brain morphology changes were significantly associated clinical diagnosis, in addition, blood pressure was highly associated with VR score and WMH. These results suggest that MRI is a valuable measure of brain injury in a Chinese cohort and can serve to assess the effects of various degenerative and cerebrovascular pathologies.

He, Jing; Iosif, Ana-Maria; Lee, Dong Young; Martinez, Oliver; Ding, Ding; Carmichael, Owen; Mortimer, James A.; Zhao, Qianhua; Chu, Shugang; Guo, Qihao; Galasko, Douglas; Salmon, David; Dai, Qi; Wu, Yougui; Petersen, Ron; Hong, Zhen; Borenstein, Amy R.; DeCarli, Charles

2010-01-01

153

Morphology and evolutionary biology of the dolphin (Delphinus sp.) brain--MR imaging and conventional histology.  

PubMed

Whole brains of the common dolphin (Delphinus delphis) were studied using magnetic resonance imaging (MRI) in parallel with conventional histology. One formalin-fixed brain was documented with a Siemens Trio Magnetic Resonance scanner and compared to three other brains which were embedded in celloidin, sectioned in the three main planes and stained for cells and fibers. The brain of the common dolphin is large, with the telencephalic hemispheres dominating the brain stem. The neocortex is voluminous and the cortical grey matter thin but extremely extended and densely convoluted. There is no olfactory ventricular recess due to the lack of an anterior olfactory system (olfactory bulb and peduncle). No occipital lobe of the telencephalic hemisphere and no posterior horn of the lateral ventricle are present. A pineal organ could not be detected. The brain stem is thick and underlies a very large cerebellum. The hippocampus and mammillary body are small and the fornix is thin; in contrast, the amygdaloid complex is large and the cortex of the limbic lobe is extended. The visual system is well developed but exceeded by the robust auditory system; for example, the inferior colliculus is several times larger than the superior colliculus. Other impressive structures in the brainstem are the peculiar elliptic nucleus, inferior olive, and in the cerebellum the huge paraflocculus and the very large posterior interpositus nucleus. There is good correspondence between MR scans and histological sections. Most of the brain characteristics can be interpreted as morphological correlates to the successful expansion of this species in the marine environment, which was characterized by the development of a powerful sonar system for localization, communication, and acousticomotor navigation. PMID:17975302

Oelschläger, H H A; Haas-Rioth, M; Fung, C; Ridgway, S H; Knauth, M

2007-10-05

154

The Relationship between Social Defiance, Vindictiveness, Anger, and Brain Morphology in Eight-Year-Old Boys and Girls  

ERIC Educational Resources Information Center

|The goal of this study is twofold: (1) to assess brain anatomical differences between children meeting diagnostic criteria for oppositional defiant disorder (ODD) and healthy controls, and (2) to investigate whether morphological brain characteristics associated with ODD differ in boys and girls. Eight-year-old participants (N = 38) were scanned…

Fahim, Cherine; Fiori, Marina; Evans, Alan C.; Perusse, Daniel

2012-01-01

155

Neural connectivity in hand sensorimotor brain areas: an evaluation by evoked field morphology.  

PubMed

The connectivity pattern of the neural network devoted to sensory processing depends on the timing of relay recruitment from receptors to cortical areas. The aim of the present work was to uncover and quantify the way the cortical relay recruitment is reflected in the shape of the brain-evoked responses. We recorded the magnetic somatosensory evoked fields (SEF) generated in 36 volunteers by separate bilateral electrical stimulation of median nerve, thumb, and little fingers. After defining an index that quantifies the shape similarity of two SEF traces, we studied the morphologic characteristics of the recorded SEFs within the 20-ms time window that followed the impulse arrival at the primary sensory cortex. Based on our similarity criterion, the shape of the SEFs obtained stimulating the median nerve was observed to be more similar to the one obtained from the thumb (same median nerve innervation) than to the one obtained from the little finger (ulnar nerve innervation). In addition, SEF shapes associated with different brain regions were more similar within an individual than between subjects. Because the SEF morphologic characteristics turned out to be quite diverse among subjects, we defined similarity levels that allowed us to identify three main classes of SEF shapes in normalcy. We show evidence that the morphology of the evoked response describes the anatomo-functional connectivity pattern in the primary sensory areas. Our findings suggest the possible existence of a thalamo-cortico-thalamic responsiveness loop related to the different classes. PMID:15468154

Tecchio, Franca; Zappasodi, Filippo; Pasqualetti, Patrizio; Rossini, Paolo Maria

2005-02-01

156

Rapid morphological brain abnormalities during acute methamphetamine intoxication in the rat: An experimental study using light and electron microscopy  

Microsoft Academic Search

This study describes morphological abnormalities of brain cells during acute methamphetamine (METH) intoxication in the rat and demonstrates the role of hyperthermia, disruption of the blood–brain barrier (BBB) and edema in their development. Rats with chronically implanted brain, muscle and skin temperature probes and an intravenous (i.v.) catheter were exposed to METH (9mg\\/kg) at standard (23°C) and warm (29°C) ambient

Hari S. Sharma; Eugene A. Kiyatkin

2009-01-01

157

Cognitive impact of genetic variation of the serotonin transporter in primates is associated with differences in brain morphology rather than serotonin neurotransmission  

PubMed Central

A powerful convergence of genetics, neuroimaging and epidemiological research has identified biological pathways mediating individual differences in complex behavioral processes and related risk for disease. Orthologous genetic variation in non-human primates represents a unique opportunity to characterize the detailed molecular and cellular mechanisms which bias behaviorally- and clinically-relevant brain function. We report that a rhesus macaque orthologue of a common polymorphism of the serotonin transporter gene (rh5-HTTLPR) has strikingly similar effects on behavior and brain morphology to those in humans. Specifically, the rh5-HTTLPR Short allele broadly impacts cognitive choice behavior and brain morphology without observably affecting 5-HT transporter or 5-HT1A concentrations in vivo. Collectively, our findings indicate that 5-HTTLPR-associated behavioral effects reflect genotype-dependent biases in cortical development rather than static differences in serotonergic signaling mechanisms. Moreover, these data highlight the vast potential of non-human primate models in advancing our understanding of human genetic variation impacting behavior and neuropsychiatric disease liability.

Jedema, Hank P.; Gianaros, Peter J.; Greer, Phillip J.; Kerr, Dustin D.; Liu, Shijing; Higley, James D.; Suomi, Stephen J.; Olsen, Adam S.; Porter, Jessica N.; Lopresti, Brian J.; Hariri, Ahmad R.; Bradberry, Charles W.

2009-01-01

158

Evolutionary origins of human brain and spirituality.  

PubMed

Evolving brains produce minds. Minds operate on imaginary entities. Thus they can create what does not exist in the physical world. Spirits can be deified. Perception of spiritual entities is emotional--organic. Spirituality is a part of culture while culture is an adaptive mechanism of human groups as it allows for technology and social organization to support survival and reproduction. Humans are not rational, they are emotional. Most of explanations of the world, offered by various cultures, involve an element of "fiat", a will of a higher spiritual being, or a reference to some ideal. From this the rules of behaviour are deduced. These rules are necessary to maintain social peace and allow a complex unit consisting of individuals of both sexes and all ages to function in a way ensuring their reproductive success and thus survival. There is thus a direct biological benefit of complex ideological superstructure of culture. This complex superstructure most often takes a form of religion in which logic is mixed with appeals to emotions based on images of spiritual beings. God is a consequence of natural evolution. Whether a deity is a cause of this evolution is difficult to discover, but existence of a deity cannot be questioned. PMID:20440961

Henneberg, Maciej; Saniotis, Arthur

2009-12-01

159

Brain homogenates from human tauopathies induce tau inclusions in mouse brain.  

PubMed

Filamentous inclusions made of hyperphosphorylated tau are characteristic of numerous human neurodegenerative diseases, including Alzheimer's disease, tangle-only dementia, Pick disease, argyrophilic grain disease (AGD), progressive supranuclear palsy, and corticobasal degeneration. In Alzheimer's disease and AGD, it has been shown that filamentous tau appears to spread in a stereotypic manner as the disease progresses. We previously demonstrated that the injection of brain extracts from human mutant P301S tau-expressing transgenic mice into the brains of mice transgenic for wild-type human tau (line ALZ17) resulted in the assembly of wild-type human tau into filaments and the spreading of tau inclusions from the injection sites to anatomically connected brain regions. Here we injected brain extracts from humans who had died with various tauopathies into the hippocampus and cerebral cortex of ALZ17 mice. Argyrophilic tau inclusions formed in all cases and following the injection of the corresponding brain extracts, we recapitulated the hallmark lesions of AGD, PSP and CBD. Similar inclusions also formed after intracerebral injection of brain homogenates from human tauopathies into nontransgenic mice. Moreover, the induced formation of tau aggregates could be propagated between mouse brains. These findings suggest that once tau aggregates have formed in discrete brain areas, they become self-propagating and spread in a prion-like manner. PMID:23690619

Clavaguera, Florence; Akatsu, Hiroyasu; Fraser, Graham; Crowther, R Anthony; Frank, Stephan; Hench, Jürgen; Probst, Alphonse; Winkler, David T; Reichwald, Julia; Staufenbiel, Matthias; Ghetti, Bernardino; Goedert, Michel; Tolnay, Markus

2013-05-20

160

Aneuploidy and Confined Chromosomal Mosaicism in the Developing Human Brain  

PubMed Central

Background Understanding the mechanisms underlying generation of neuronal variability and complexity remains the central challenge for neuroscience. Structural variation in the neuronal genome is likely to be one important mechanism for neuronal diversity and brain diseases. Large-scale genomic variations due to loss or gain of whole chromosomes (aneuploidy) have been described in cells of the normal and diseased human brain, which are generated from neural stem cells during intrauterine period of life. However, the incidence of aneuploidy in the developing human brain and its impact on the brain development and function are obscure. Methodology/Principal Findings To address genomic variation during development we surveyed aneuploidy/polyploidy in the human fetal tissues by advanced molecular-cytogenetic techniques at the single-cell level. Here we show that the human developing brain has mosaic nature, being composed of euploid and aneuploid neural cells. Studying over 600,000 neural cells, we have determined the average aneuploidy frequency as 1.25–1.45% per chromosome, with the overall percentage of aneuploidy tending to approach 30–35%. Furthermore, we found that mosaic aneuploidy can be exclusively confined to the brain. Conclusions/Significance Our data indicates aneuploidization to be an additional pathological mechanism for neuronal genome diversification. These findings highlight the involvement of aneuploidy in the human brain development and suggest an unexpected link between developmental chromosomal instability, intercellural/intertissular genome diversity and human brain diseases.

Liehr, Thomas; Kolotii, Alexei D.; Kutsev, Sergei I.; Pellestor, Franck; Beresheva, Alfia K.; Demidova, Irina A.; Kravets, Viktor S.; Monakhov, Viktor V.; Soloviev, Ilia V.

2007-01-01

161

Cannabis abuse and brain morphology in schizophrenia: a review of the available evidence.  

PubMed

Substance abuse is the most prevalent comorbid psychiatric condition associated with schizophrenia, and cannabis is the illicit drug most often abused. Apart from worsening the course of schizophrenia, frequent cannabis use especially at an early age seems to be an important risk factor for developing schizophrenia. Although a large body of neuroimaging studies gives evidence for structural alterations in many different brain regions in schizophrenia patients, there is still limited knowledge of the impact of cannabis abuse on brain structure in schizophrenia. We performed a systematic review including structural magnetic resonance imaging studies comparing high-risk and schizophrenia patients with and without cannabis abuse and found inconclusive results. While there is some evidence that chronic cannabis abuse could alter brain morphology in schizophrenia in patients continuing their cannabis consumption, there is no convincing evidence that this alteration takes place before the onset of schizophrenia when looking at first-episode patients. There is some weak evidence that cannabis abuse could affect brain structures in high-risk subjects, but replication of these studies is needed. PMID:22907121

Malchow, Berend; Hasan, Alkomiet; Fusar-Poli, Paolo; Schmitt, Andrea; Falkai, Peter; Wobrock, Thomas

2012-08-21

162

Why Our Kids Can Write; or, Running Slo's through the Right Brain Equals the Morphology of Diddley Doos.  

ERIC Educational Resources Information Center

Proposes that offering students activities that exercise right-brain functions (nonverbal, nonrational, spatial, and intuitive) helps students become more fully developed human beings and better writers. (RL)

Palmer, Thelma

1980-01-01

163

Why Our Kids Can Write; or, Running Slo's through the Right Brain Equals the Morphology of Diddley Doos.  

ERIC Educational Resources Information Center

|Proposes that offering students activities that exercise right-brain functions (nonverbal, nonrational, spatial, and intuitive) helps students become more fully developed human beings and better writers. (RL)|

Palmer, Thelma

1980-01-01

164

[Survival of the fattest: the key to human brain evolution].  

PubMed

The circumstances of human brain evolution are of central importance to accounting for human origins, yet are still poorly understood. Human evolution is usually portrayed as having occurred in a hot, dry climate in East Africa where the earliest human ancestors became bipedal and evolved tool-making skills and language while struggling to survive in a wooded or savannah environment. At least three points need to be recognised when constructing concepts of human brain evolution : (1) The human brain cannot develop normally without a reliable supply of several nutrients, notably docosahexaenoic acid, iodine and iron. (2) At term, the human fetus has about 13 % of body weight as fat, a key form of energy insurance supporting brain development that is not found in other primates. (3) The genome of humans and chimpanzees is <1 % different, so if they both evolved in essentially the same habitat, how did the human brain become so much larger, and how was its present-day nutritional vulnerability circumvented during 5-6 million years of hominid evolution ? The abundant presence of fish bones and shellfish remains in many African hominid fossil sites dating to 2 million years ago implies human ancestors commonly inhabited the shores, but this point is usually overlooked in conceptualizing how the human brain evolved. Shellfish, fish and shore-based animals and plants are the richest dietary sources of the key nutrients needed by the brain. Whether on the shores of lakes, marshes, rivers or the sea, the consumption of most shore-based foods requires no specialized skills or tools. The presence of key brain nutrients and a rich energy supply in shore-based foods would have provided the essential metabolic and nutritional support needed to gradually expand the hominid brain. Abundant availability of these foods also provided the time needed to develop and refine proto-human attributes that subsequently formed the basis of language, culture, tool making and hunting. The presence of body fat in human babies appears to be the product of a long period of sedentary, shore-based existence by the line of hominids destined to become humans, and became the unique solution to insuring a back-up fuel supply for the expanding hominid brain. Hence, survival of the fattest (babies) was the key to human brain evolution. PMID:16828044

Cunnane, Stephen C

165

Restricted Morphological and Behavioral Abnormalities following Ablation of ?-Actin in the Brain  

PubMed Central

The local translation of ?-actin is one mechanism proposed to regulate spatially-restricted actin polymerization crucial for nearly all aspects of neuronal development and function. However, the physiological significance of localized ?-actin translation in neurons has not yet been demonstrated in vivo. To investigate the role of ?-actin in the mammalian central nervous system (CNS), we characterized brain structure and function in a CNS-specific ?-actin knock-out mouse (CNS-ActbKO). ?-actin was rapidly ablated in the embryonic mouse brain, but total actin levels were maintained through upregulation of other actin isoforms during development. CNS-ActbKO mice exhibited partial perinatal lethality while survivors presented with surprisingly restricted histological abnormalities localized to the hippocampus and cerebellum. These tissue morphology defects correlated with profound hyperactivity as well as cognitive and maternal behavior impairments. Finally, we also identified localized defects in axonal crossing of the corpus callosum in CNS-ActbKO mice. These restricted defects occurred despite the fact that primary neurons lacking ?-actin in culture were morphologically normal. Altogether, we identified novel roles for ?-actin in promoting complex CNS tissue architecture while also demonstrating that distinct functions for the ubiquitously expressed ?-actin are surprisingly restricted in vivo.

Cheever, Thomas R.; Li, Bin; Ervasti, James M.

2012-01-01

166

Progression of neurodegeneration and morphologic changes in the brains of juvenile mice with selenoprotein P deleted  

PubMed Central

Selenoprotein P (Sepp1) is an important protein involved in selenium (Se) transport and homeostasis. Severe neurologic dysfunction develops in Sepp1 null mice (Sepp1?/?) fed a selenium-deficient diet. Sepp1?/? mice fed a selenium-deficient diet have extensive degeneration of the brainstem and thalamus, and even when supplemented with selenium exhibit subtle learning deficits and altered basal synaptic transmission and short-term plasticity in the CA1 region of the hippocampus. The goal of this study was to delineate the regional progression of neurodegeneration in the brain, determine the extent of neuronal cell death, and evaluate neurite structural changes within the hippocampus of Sepp1?/? mice. Whole brain serial sections of wild-type and Sepp1?/? mice maintained on selenium-deficient or supplemented diets over the course of 12 days from weaning were evaluated with amino cupric silver neurodegeneration stain. The neurodegeneration was present in all regions upon weaning and progressed over 12 days in Sepp1?/? mice fed selenium-deficient diet, except in the medial forebrain bundle and somatosensory cortex where the neurodegeneration developed post-weaning. The neurodegeneration was predominantly axonal, however the somatosensory cortex and lateral striatum showed silver-stained neurons. Morphologic analysis of the hippocampus revealed decreased dendritic length and spine density, suggesting that loss of Sepp1 also causes subtle changes in the brain that can contribute to functional deficits. These data illustrate that deletion of Sepp1, and presumably selenium deficiency in the brain, produce both neuronal and axonal degeneration as well as more moderate and potentially reversible neurite changes in the developing brain.

Caito, Samuel W.; Milatovic, Dejan; Hill, Kristina E.; Aschner, Michael; Burk, Raymond F.; Valentine, William M.

2011-01-01

167

Altered brain sodium channel transcript levels in human epilepsy  

Microsoft Academic Search

Normal, and perhaps pathological, characteristics of neuronal excitability are related to the distribution and density of voltage-gated ion channels such as the sodium channel. We studied normal and epileptic human brain using the ligase detection reaction to measure the relative quantities of mRNAs encoding sodium channel subtypes 1 and 2. Normal brains exhibited characteristic 1:2 ratios which varied by brain

Anthony J. Lombardo; Ruben Kuzniecky; Richard E. Powers; George B. Brown

1996-01-01

168

Ultrastructural pathology of endothelial tight junctions in human brain oedema.  

PubMed

Cortical biopsies of patients with the diagnosis of complicated brain trauma, congenital hydrocephalus, brain vascular anomaly, and brain tumour are studied with the electron microscope using cortical biopsies of different cortical brain regions to analyze the alterations of endothelial junctions, and their participation in the pathogenesis of human brain oedema. In moderate oedema, most endothelial tight junctions are structurally closed and intact, while in some cases of severe oedema, the opening of tight endothelial junctions is observed. In very severe brain oedema, a considerable enlargement of interjunctional pockets of extracellular space is also seen suggesting that in highly increased cerebrovascular permeability, the endothelial junctions are open in their entire extent, and that an intercellular or paracellular route through interendothelial clefts for transferring haematogenous oedema fluid from blood to the capillary basement membrane and the brain parenchyma is formed, contributing to the formation of brain oedema. High intensity brain trauma, seizures, osmotic forces, hypoxic conditions, and alteration of tight junctions proteins would explain the opening of endothelial junctions in severe and complicated brain oedema. In congenital hydrocephalus, the capillary wall shows evident signs of blood-brain barrier dysfunction characterized by closed and open interendothelial junctions, increased endothelial vesicular and vacuolar transport, thin and fragmented basement membrane with areas of focal thickening, and discontinuous perivascular astrocytic end-feet. The perivascular space is notably dilated and widely communicated with the enlarged extracellular space in the neuropil, showing the contribution of damaged endothelial junction to the formation of interstitial or hydrocephalic brain oedema. Altered expression of tight junction proteins could cause a blood-brain barrier breakdown following brain injury and hypoxic conditions leading to brain oedema. The results are compared with those found in experimental brain oedema. Some controversial results are also described. PMID:22773457

Castejón, Orlando J

2012-01-01

169

BrainMap: A Database of Functional Neuroanatomy Derived from Human Brain Images.  

National Technical Information Service (NTIS)

The goal of the BrainMap project is to promote efficient compilation, analysis, and dissemination of the rapidly growing body of information about the functional organization of the human brain which can be provided by medical imaging techniques such as P...

1991-01-01

170

Images of the working brain: understanding human brain function with positron emission tomography  

Microsoft Academic Search

In the past 15 years positron emission tomography (PET) has become a settled method of imaging the functioning human brain, both in normal volunteers and in patients with various disorders. Much of the work on sensory systems has been on the visual system, a conveniently studied and very important part of the brain. The motor system in health and disease

John D. G Watson

1997-01-01

171

EEG\\/MEG brain mapping of human pain: recent advances  

Microsoft Academic Search

The scientific study of EEG and MEG brain mapping of human pain started around 25 years ago. Few progresses have been made on the quantitative analyses of the EEG power frequency effect on the brain in both clinical pain and laboratory-controlled studies. It shall be noted that the tonic states of on-going pain are best to be described by EEG

Andrew C. N Chen

2002-01-01

172

Quantitative imaging of energy expenditure in human brain.  

PubMed

Despite the essential role of the brain energy generated from ATP hydrolysis in supporting cortical neuronal activity and brain function, it is challenging to noninvasively image and directly quantify the energy expenditure in the human brain. In this study, we applied an advanced in vivo(31)P MRS imaging approach to obtain regional cerebral metabolic rates of high-energy phosphate reactions catalyzed by ATPase (CMR(ATPase)) and creatine kinase (CMR(CK)), and to determine CMR(ATPase) and CMR(CK) in pure gray mater (GM) and white mater (WM), respectively. It was found that both ATPase and CK rates are three times higher in GM than WM; and CMR(CK) is seven times higher than CMR(ATPase) in GM and WM. Among the total brain ATP consumption in the human cortical GM and WM, 77% of them are used by GM in which approximately 96% is by neurons. A single cortical neuron utilizes approximately 4.7 billion ATPs per second in a resting human brain. This study demonstrates the unique utility of in vivo(31)P MRS imaging modality for direct imaging of brain energy generated from ATP hydrolysis, and provides new insights into the human brain energetics and its role in supporting neuronal activity and brain function. PMID:22487547

Zhu, Xiao-Hong; Qiao, Hongyan; Du, Fei; Xiong, Qiang; Liu, Xiao; Zhang, Xiaoliang; Ugurbil, Kamil; Chen, Wei

2012-02-17

173

Human brain-teleoperated robot between remote places  

Microsoft Academic Search

This paper describes an EEG-based human brain- actuated robotic system, which allows performing navigation and visual exploration tasks between remote places via internet, using only brain activity. In operation, two teleoperation modes can be combined: robot navigation and camera exploration. In both modes, the user faces a real-time video captured by the robot camera merged with augmented reality items. In

Carlos Escolano; Javier Antelis; Javier Minguez

2009-01-01

174

Quantitative Imaging of Energy Expenditure in Human Brain  

PubMed Central

Despite the essential role of the brain energy generated from ATP hydrolysis in supporting cortical neuronal activity and brain function, it is challenging to noninvasively image and directly quantify the energy expenditure in the human brain. In this study, we applied an advanced in vivo 31P MRS imaging approach to obtain regional cerebral metabolic rates of high-energy phosphate reactions catalyzed by ATPase (CMRATPase) and creatine kinase (CMRCK), and to determine CMRATPase and CMRCK in pure grey mater (GM) and white mater (WM), respectively. It was found that both ATPase and CK rates are three times higher in GM than WM; and CMRCK is seven times higher than CMRATPase in GM and WM. Among the total brain ATP consumption in the human cortical GM and WM, 77% of them are used by GM in which approximately 96% is by neurons. A single cortical neuron utilizes approximately 4.7 billion ATPs per second in a resting human brain. This study demonstrates the unique utility of in vivo 31P MRS imaging modality for direct imaging of brain energy generated from ATP hydrolysis, and provides new insights into the human brain energetics and its role in supporting neuronal activity and brain function.

Zhu, Xiao-Hong; Qiao, Hongyan; Du, Fei; Xiong, Qiang; Liu, Xiao; Zhang, Xiaoliang; Ugurbil, Kamil; Chen, Wei

2012-01-01

175

Localization of Leptin Receptor in the Human Brain  

Microsoft Academic Search

Leptin (OB protein), the product of the adipose-specific ob gene, exerts important effects in the regulation of food intake and energy expenditure. Based upon results from animal studies, several groups have suggested that this action may be exerted in the brain, specifically in the hypothalamic region. However, to date, the localization of the OB-R in the human brain has not

Marta E. Couce; Bartolome Burguera; Joseph E. Parisi; Michael D. Jensen; Ricardo V. Lloyd

1997-01-01

176

Biomechanics of Traumatic Brain Injury: Influences of the Morphologic Heterogeneities of the Cerebral Cortex  

PubMed Central

Traumatic brain injury (TBI) can be caused by accidents and often leads to permanent health issues or even death. Brain injury criteria are used for assessing the probability of TBI, if a certain mechanical load is applied. The currently used injury criteria in the automotive industry are based on global head kinematics. New methods, based on finite element modeling, use brain injury criteria at lower scale levels, e.g., tissue-based injury criteria. However, most current computational head models lack the anatomical details of the cerebrum. To investigate the influence of the morphologic heterogeneities of the cerebral cortex, a numerical model of a representative part of the cerebral cortex with a detailed geometry has been developed. Several different geometries containing gyri and sulci have been developed for this model. Also, a homogeneous geometry has been made to analyze the relative importance of the heterogeneities. The loading conditions are based on a computational head model simulation. The results of this model indicate that the heterogeneities have an influence on the equivalent stress. The maximum equivalent stress in the heterogeneous models is increased by a factor of about 1.3–1.9 with respect to the homogeneous model, whereas the mean equivalent stress is increased by at most 10%. This implies that tissue-based injury criteria may not be accurately applied to most computational head models used nowadays, which do not account for sulci and gyri.

Gervaise, H.M.T.; van Dommelen, J.A.W.; Geers, M.G.D.

2008-01-01

177

Reliability issues in human brain temperature measurement  

PubMed Central

Introduction The influence of brain temperature on clinical outcome after severe brain trauma is currently poorly understood. When brain temperature is measured directly, different values between the inside and outside of the head can occur. It is not yet clear if these differences are 'real' or due to measurement error. Methods The aim of this study was to assess the performance and measurement uncertainty of body and brain temperature sensors currently in use in neurocritical care. Two organic fixed-point, ultra stable temperature sources were used as the temperature references. Two different types of brain sensor (brain type 1 and brain type 2) and one body type sensor were tested under rigorous laboratory conditions and at the bedside. Measurement uncertainty was calculated using internationally recognised methods. Results Average differences between the 26°C reference temperature source and the clinical temperature sensors were +0.11°C (brain type 1), +0.24°C (brain type 2) and -0.15°C (body type), respectively. For the 36°C temperature reference source, average differences between the reference source and clinical thermometers were -0.02°C, +0.09°C and -0.03°C for brain type 1, brain type 2 and body type sensor, respectively. Repeat calibrations the following day confirmed that these results were within the calculated uncertainties. The results of the immersion tests revealed that the reading of the body type sensor was sensitive to position, with differences in temperature of -0.5°C to -1.4°C observed on withdrawing the thermometer from the base of the isothermal environment by 4 cm and 8 cm, respectively. Taking into account all the factors tested during the calibration experiments, the measurement uncertainty of the clinical sensors against the (nominal) 26°C and 36°C temperature reference sources for the brain type 1, brain type 2 and body type sensors were ± 0.18°C, ± 0.10°C and ± 0.12°C respectively. Conclusions The results show that brain temperature sensors are fundamentally accurate and the measurements are precise to within 0.1 to 0.2°C. Subtle dissociation between brain and body temperature in excess of 0.1 to 0.2°C is likely to be real. Body temperature sensors need to be secured in position to ensure that measurements are reliable.

2009-01-01

178

Self-Stimulation Alters Human Sensory Brain Responses  

Microsoft Academic Search

Human electrocortical potentials evoked by self-administered auditory and visual stimuli manifest much smaller amplitude and faster poststimulus timing than do average brain responses evoked by identical machine-delivered stimuli. Auditory evoked potentials show this \\

Edward W. P. Schafer; Marilyn M. Marcus

1973-01-01

179

Brain tumour stem cells: the undercurrents of human brain cancer and their relationship to neural stem cells  

Microsoft Academic Search

Conceptual and technical advances in neural stem cell biology are being applied to the study of human brain tumours. These studies suggest that human brain tumours are organized as a hierarchy and are maintained by a small number of tumour cells that have stem cell properties. Most of the bulk population of human brain tumours comprise cells that have lost

Peter B. Dirks

2008-01-01

180

Overview of the human brain as a distributed computing network  

SciTech Connect

The hierarchically organized human brain is viewed as a prime example of a massively parallel, adaptive information processing and process control system. A brief overview of the human brain is provided for computer architects, in hopes that the principles of massive parallelism, dense connectivity and self-organization of assemblies of processing elements will prove relevant to the design of fifth generation VLSI computing networks. 6 references.

Gevins, A.S.

1983-01-01

181

BrainKnowledge: A Human Brain Function Mapping Knowledge-Base System  

Microsoft Academic Search

Associating fMRI image datasets with the available literature is crucial for the analysis and interpretation of fMRI data.\\u000a Here, we present a human brain function mapping knowledge-base system (BrainKnowledge) that associates fMRI data analysis\\u000a and literature search functions. BrainKnowledge not only contains indexed literature, but also provides the ability to compare\\u000a experimental data with those derived from the literature. BrainKnowledge

Mei-Yu Hsiao; Chien-Chung Chen; Jyh-Horng Chen

2011-01-01

182

DUF1220 domains, cognitive disease, and human brain evolution.  

PubMed

We have established that human genome sequences encoding a novel protein domain, DUF1220, show a dramatically elevated copy number in the human lineage (>200 copies in humans vs. 1 in mouse/rat) and may be important to human evolutionary adaptation. Copy-number variations (CNVs) in the 1q21.1 region, where most DUF1220 sequences map, have now been implicated in numerous diseases associated with cognitive dysfunction, including autism, autism spectrum disorder, mental retardation, schizophrenia, microcephaly, and macrocephaly. We report here that these disease-related 1q21.1 CNVs either encompass or are directly flanked by DUF1220 sequences and exhibit a dosage-related correlation with human brain size. Microcephaly-producing 1q21.1 CNVs are deletions, whereas macrocephaly-producing 1q21.1 CNVs are duplications. Similarly, 1q21.1 deletions and smaller brain size are linked with schizophrenia, whereas 1q21.1 duplications and larger brain size are associated with autism. Interestingly, these two diseases are thought to be phenotypic opposites. These data suggest a model which proposes that (1) DUF1220 domain copy number may be involved in influencing human brain size and (2) the evolutionary advantage of rapidly increasing DUF1220 copy number in the human lineage has resulted in favoring retention of the high genomic instability of the 1q21.1 region, which, in turn, has precipitated a spectrum of recurrent human brain and developmental disorders. PMID:19850849

Dumas, L; Sikela, J M

2009-10-22

183

Estimating Neural Signal Dynamics in the Human Brain  

PubMed Central

Although brain imaging methods are highly effective for localizing the effects of neural activation throughout the human brain in terms of the blood oxygenation level dependent (BOLD) response, there is currently no way to estimate the underlying neural signal dynamics in generating the BOLD response in each local activation region (except for processes slower than the BOLD time course). Knowledge of the neural signal is critical if spatial mapping is to progress to the analysis of dynamic information flow through the cortical networks as the brain performs its tasks. We introduce an analytic approach that provides a new level of conceptualization and specificity in the study of brain processing by non-invasive methods. This technique allows us to use brain imaging methods to determine the dynamics of local neural population responses to their native temporal resolution throughout the human brain, with relatively narrow confidence intervals on many response properties. The ability to characterize local neural dynamics in the human brain represents a significant enhancement of brain imaging capabilities, with potential applications ranging from general cognitive studies to assessment of neuropathologies.

Tyler, Christopher W.; Likova, Lora T.

2011-01-01

184

Near infrared Raman spectra of human brain lipids  

NASA Astrophysics Data System (ADS)

Human brain tissue, in particular white matter, contains high lipid content. These brain lipids can be divided into three principal classes: neutral lipids including the steroid cholesterol, phospholipids and sphingolipids. Major lipids in normal human brain tissue are phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, phosphatidic acid, sphingomyelin, galactocerebrosides, gangliosides, sulfatides and cholesterol. Minor lipids are cholesterolester and triacylglycerides. During transformation from normal brain tissue to tumors, composition and concentration of lipids change in a specific way. Therefore, analysis of lipids might be used as a diagnostic parameter to distinguish normal tissue from tumors and to determine the tumor type and tumor grade. Raman spectroscopy has been suggested as an analytical tool to detect these changes even under intra-operative conditions. We recorded Raman spectra of the 12 major and minor brain lipids with 785 nm excitation in order to identify their spectral fingerprints for qualitative and quantitative analyses.

Krafft, Christoph; Neudert, Lars; Simat, Thomas; Salzer, Reiner

2005-05-01

185

Imaging structural co-variance between human brain regions.  

PubMed

Brain structure varies between people in a markedly organized fashion. Communities of brain regions co-vary in their morphological properties. For example, cortical thickness in one region influences the thickness of structurally and functionally connected regions. Such networks of structural co-variance partially recapitulate the functional networks of healthy individuals and the foci of grey matter loss in neurodegenerative disease. This architecture is genetically heritable, is associated with behavioural and cognitive abilities and is changed systematically across the lifespan. The biological meaning of this structural co-variance remains controversial, but it appears to reflect developmental coordination or synchronized maturation between areas of the brain. This Review discusses the state of current research into brain structural co-variance, its underlying mechanisms and its potential value in the understanding of various neurological and psychiatric conditions. PMID:23531697

Alexander-Bloch, Aaron; Giedd, Jay N; Bullmore, Ed

2013-03-27

186

Neuroglobin and cytoglobin expression in the human brain.  

PubMed

Neuroglobin and cytoglobin are new members of the heme-globin family. Both globins are primarily expressed in neurons of the brain and retina. Neuroglobin and cytoglobin have been suggested as novel therapeutic targets in various neurodegenerative diseases based on their oxygen binding and cell protecting properties. However, findings in Neuroglobin-deficient mice question the endogenous neuroprotective properties. The expression pattern of neuroglobin and cytoglobin in the rodent brain is also in contradiction to a major role of neuronal protection. In a recent study, neuroglobin was ubiquitously expressed and up-regulated following stroke in the human brain. The present study aimed at confirming our previous observations in rodents using two post-mortem human brains. The anatomical localization of neuroglobin and cytoglobin in the human brain is much like what has been described for the rodent brain. Neuroglobin is highly expressed in the hypothalamus, amygdale and in the pontine tegmental nuclei, but not in the hippocampus. Cytoglobin is highly expressed in the habenula, hypothalamus, thalamus, hippocampus and the pontine tegmental nuclei. We only detected a low expression of neuroglobin and cytoglobin in the cerebral cortex, while no expression in the cerebellar cortex was detectable. We provide a neuroanatomical indication for a different role of neuroglobin and cytoglobin in the human brain. PMID:23160832

Hundahl, Christian Ansgar; Kelsen, Jesper; Hay-Schmidt, Anders

2012-11-17

187

Revealing Modular Architecture of Human Brain Structural Networks by Using Cortical Thickness from MRI  

PubMed Central

Modularity, presumably shaped by evolutionary constraints, underlies the functionality of most complex networks ranged from social to biological networks. However, it remains largely unknown in human cortical networks. In a previous study, we demonstrated a network of correlations of cortical thickness among specific cortical areas and speculated that these correlations reflected an underlying structural connectivity among those brain regions. Here, we further investigated the intrinsic modular architecture of the human brain network derived from cortical thickness measurement. Modules were defined as groups of cortical regions that are connected morphologically to achieve the maximum network modularity. We show that the human cortical network is organized into 6 topological modules that closely overlap known functional domains such as auditory/language, strategic/executive, sensorimotor, visual, and mnemonic processing. The identified structure-based modular architecture may provide new insights into the functionality of cortical regions and connections between structural brain modules. This study provides the first report of modular architecture of the structural network in the human brain using cortical thickness measurements.

Chen, Zhang J.; He, Yong; Rosa-Neto, Pedro; Germann, Jurgen

2008-01-01

188

Human brain activity with functional NIR optical imager  

NASA Astrophysics Data System (ADS)

In this paper we reviewed the applications of functional near infrared optical imager in human brain activity. Optical imaging results of brain activity, including memory for new association, emotional thinking, mental arithmetic, pattern recognition ' where's Waldo?, occipital cortex in visual stimulation, and motor cortex in finger tapping, are demonstrated. It is shown that the NIR optical method opens up new fields of study of the human population, in adults under conditions of simulated or real stress that may have important effects upon functional performance. It makes practical and affordable for large populations the complex technology of measuring brain function. It is portable and low cost. In cognitive tasks subjects could report orally. The temporal resolution could be millisecond or less in theory. NIR method will have good prospects in exploring human brain secret.

Luo, Qingming

2001-08-01

189

Understanding complexity in the human brain.  

PubMed

Although the ultimate aim of neuroscientific enquiry is to gain an understanding of the brain and how its workings relate to the mind, the majority of current efforts are largely focused on small questions using increasingly detailed data. However, it might be possible to successfully address the larger question of mind-brain mechanisms if the cumulative findings from these neuroscientific studies are coupled with complementary approaches from physics and philosophy. The brain, we argue, can be understood as a complex system or network, in which mental states emerge from the interaction between multiple physical and functional levels. Achieving further conceptual progress will crucially depend on broad-scale discussions regarding the properties of cognition and the tools that are currently available or must be developed in order to study mind-brain mechanisms. PMID:21497128

Bassett, Danielle S; Gazzaniga, Michael S

2011-04-14

190

Human Brain Mapping: Experimental and Computation Approaches.  

National Technical Information Service (NTIS)

This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This program development project combined Los Alamos' and collaborators' strengths in noninvasive brain ima...

C. C. Wood J. S. George D. M. Schmidt C. J. Aine J. Sandor J. Belliveau

1998-01-01

191

Understanding complexity in the human brain  

PubMed Central

Although the ultimate aim of neuroscientific enquiry is to gain an understanding of the brain and how its workings relate to the mind, the majority of current efforts are largely focused on small questions using increasingly detailed data. However, it might be possible to successfully address the larger question of mind–brain mechanisms if the cumulative findings from these neuroscientific studies are coupled with complementary approaches from physics and philosophy. The brain, we argue, can be understood as a complex system or network, in which mental states emerge from the interaction between multiple physical and functional levels. Achieving further conceptual progress will crucially depend on broad-scale discussions regarding the properties of cognition and the tools that are currently available or must be developed in order to study mind–brain mechanisms.

Bassett, Danielle S.; Gazzaniga, Michael S.

2011-01-01

192

Imaging of the Developing Brain  

Microsoft Academic Search

The human brain undergoes changes in morphology, volume, composition and function during brain maturation. Of the various available medical imaging investigations, ultrasound and MRI are most commonly used for assessing the developing brain. Being radiation-free and non-invasive, both imaging modalities allow in vivo serial examinations of the brain during maturation without health risks. In addition, MRI has the benefit of

Gregory E. Antonio; Winnie C. W. Chu; David K. W. Yeung; Anil T. Ahuja

2008-01-01

193

Cholesteryl ester transfer protein in human brain  

Microsoft Academic Search

Summary  The evidence that apolipoproteins are found in the cerebrospinal fluid and low-density lipoprotein receptor is found in the\\u000a brain suggests that the brain may have an active lipid transport system. In plasma, cholesteryl ester transfer protein mediates\\u000a the exchange and net transfer of cholesteryl ester and triglycerides among lipoproteins. Cholesteryl ester transfer activity\\u000a was measured in the cerebrospinal fluid and

John J. Albers; John H. Tollefson; Gertrud Wolfbauer; Robert E. Albright Jr

1992-01-01

194

Morphology of Diagnostic Stages of Intestinal Parasites of Humans.  

National Technical Information Service (NTIS)

The diagnostic stages of intestinal parasites are differentiated on the basis of specific morphologic features that can be seen microscopically. Although Dientamoeba fragilis is a flagellate, morphologically, it resembles the amebae. Therefore, in this ma...

M. M. Brooke D. M. Melvin

1984-01-01

195

Geometric variation of the frontal squama in the genus homo: frontal bulging and the origin of modern human morphology.  

PubMed

The majority of studies of frontal bone morphology in paleoanthropology have analyzed the frontal squama and the browridge as a single unit, mixing information from different functional elements. Taking into account that the bulging of the frontal bone is often described as a species-specific trait of Homo sapiens, in this article we analyze variation in the midsagittal profile of the genus Homo, focusing on the frontal squama alone, using landmark-based superimpositions and principal components analysis. Our results demonstrate that anatomically modern humans are definitely separated from extinct human taxa on the basis of frontal bulging. However, there is minor overlap among these groups, indicating that it is necessary to exercise caution when using this trait alone to make taxonomic inferences on individual specimens. Early modern humans do not show differences with recent modern humans, and "transitional" individuals such as Jebel Irhoud 1, Maba, and Florisbad, show modern-like frontal squama morphology. The bulging of the frontal squama in modern humans may represent a structural consequence of more general cranial changes, or it could be a response to changes in the morphology of the underlying prefrontal brain elements. A subtle difference between Neandertals and the Afro-European Middle Pleistocene Homo sample is associated with flattening at bregma in the former group, a result that merits further investigation. PMID:23292748

Bruner, Emiliano; Athreya, Sheela; de la Cuétara, José Manuel; Marks, Tarah

2013-01-04

196

Carboxy terminal of beta-amyloid deposits in aged human, canine, and polar bear brains.  

PubMed

Immunocytochemistry, using antibodies specific for different carboxy termini of beta-amyloid. A beta 40 and A beta 42(43), was used to compare beta-amyloid deposits in aged animal models to nondemented and demented Alzheimer's disease human cases. Aged beagle dogs exhibit diffuse plaques in the absence of neurofibrillary pathology and the aged polar bear brains contain diffuse plaques and PHF-1-positive neurofibrillary tangles. The brains of nondemented human subjects displayed abundant diffuse plaques, whereas the AD cases had both diffuse and mature (cored) neuritic plaques. Diffuse plaques were positively immunostained with an antibody against A beta 42(43) in all examined species, whereas A beta 40 immunopositive mature plaques were observed only in the human brain. Anti-A beta 40 strongly immunolabeled cerebrovascular beta-amyloid deposits in each of the species examined, although some deposits in the polar bear brain were preferentially labeled with anti-A beta 42(43). beta-amyloid deposition was evident in the outer molecular layer of the dentate gyrus in the aged dog, polar bear, and human. Within this layer, A beta 42 was present as diffuse deposits, although these deposits were morphologically distinct in each of the examined animal models. In dogs, A beta 42 was cloud-like in nature; the polar bear demonstrated a more aggregated type of deposition, and the nondemented human displayed well-defined deposits. Alzheimer's disease cases were most frequently marked by neuritic plaques in this region. Taken together, the data indicate that beta-amyloid deposition in aged mammals is similar to the earliest stages observed in human brain. In each species, A beta 42(43) is the initially deposited isoform in diffuse plaques. PMID:8744406

Tekirian, T L; Cole, G M; Russell, M J; Yang, F; Wekstein, D R; Patel, E; Snowdon, D A; Markesbery, W R; Geddes, J W

197

Sequential morphological changes in the dog brain after interstitial iodine- 125 irradiation  

SciTech Connect

Iodine- 125 seeds (3.55 mCi) were stereotactically implanted into the subcortical white matter of the left coronal gyrus in six beagle dogs. Morphological changes were studied at intervals ranging from 25 to 368 days after implantation. In all of the animals, there was a calcifying necrosis 3 to 6 mm in diameter with an adjacent small zone of demyelination. There were no signs of delayed radiation damage outside the demyelinated perifocal zone. The central tissue necrosis was sharply delineated and did not increase in size after 70 days, i.e., an accumulated dose of 18,000 cGy. In addition, widespread vasogenic edema was present in the homolateral hemisphere. The morphological changes observed differed in many aspects from those found with other radioactive sources, such as gold-198, yttrium-90, or iridium-192. The low energy gamma radiation, the absence of beta radiation, and the half-life of 60.2 days makes iodine-125 a favorable radioactive source to produce a well-defined necrosis without delayed radiation damage in the surrounding brain.

Ostertag, C.B.; Weigel, K.; Warnke, P.; Lombeck, G.; Kleihues, P.

1983-11-01

198

Human brain endothelial cells are responsive to adenosine receptor activation.  

PubMed

The blood-brain barrier (BBB) of the central nervous system (CNS) consists of a unique subset of endothelial cells that possess tight junctions which form a relatively impervious physical barrier to a large variety of blood components. Until recently, there have been no good in vitro models for studying the human BBB without the co-culture of feeder cells. The hCMEC/D3 cell line is the first stable, well-differentiated human brain endothelial cell line that grows independently in culture with characteristics that closely resemble those of resident human brain endothelial cells. As our previously published findings demonstrated the importance of adenosine receptor (AR) signaling for lymphocyte entry into the CNS, we wanted to determine if human brain endothelial cells possess the capacity to generate and respond to extracellular adenosine. Utilizing the hCMEC/D3 cell line, we determined that these cells express CD73, the cell surface enzyme that converts extracellular AMP to adenosine. When grown under normal conditions, these cells also express the A(1), A(2A), and A(2B) AR subtypes. Additionally, hCMEC/D3 cells are responsive to extracellular AR signaling, as cAMP levels increase following the addition of the broad spectrum AR agonist 5'-N-ethylcarboxamidoadenosine (NECA). Overall, these results indicate that human brain endothelial cells, and most likely the human BBB, have the capacity to synthesize and respond to extracellular adenosine. PMID:21484089

Mills, Jeffrey H; Alabanza, Leah; Weksler, Babette B; Couraud, Pierre-Olivier; Romero, Ignacio A; Bynoe, Margaret S

2011-02-17

199

Transcriptional Profiling of Human Brain Endothelial Cells Reveals Key Properties Crucial for Predictive In Vitro Blood-Brain Barrier Models  

Microsoft Academic Search

Brain microvascular endothelial cells (BEC) constitute the blood-brain barrier (BBB) which forms a dynamic interface between the blood and the central nervous system (CNS). This highly specialized interface restricts paracellular diffusion of fluids and solutes including chemicals, toxins and drugs from entering the brain. In this study we compared the transcriptome profiles of the human immortalized brain endothelial cell line

Eduard Urich; Stanley E. Lazic; Juliette Molnos; Isabelle Wells; Per-Ola Freskgård

2012-01-01

200

Comparative Diffusion Study of Two Nitrosoureas: Carmustine and Fotemustine in Normal Rat Brain, Human and Rat Brain Biopsies  

Microsoft Academic Search

In order to assess the apparent diffusion coefficient of two nitrosoureas (carmustine and fotemustine) in the brain, a model of planar diffusion was used in the rat brain and in rat and human brain biopsies. Drugs were deposed on the brain surface at a constant concentration for 30 min. At the end of the diffusion time, the concentration gradient was

A. Meulemans; B. Giroux; P. Hannoun; D. Robine; D. Henzel

1991-01-01

201

Morphological and chemical analysis of a deep brain stimulation electrode explanted from a dystonic patient.  

PubMed

Deep brain stimulation is an effective treatment for different types of dystonia; nevertheless dystonic movements could provoke hardware-related complications, including fractures or electrodes displacement. This study focuses on a morphological and structural analysis of a malfunctioning electrode removed from a dystonic patient. In this case, high impedance values and worsening of symptoms were observed. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) were performed on the explanted electrode. The qualitative and quantitative data collected from the damaged electrode were compared with a new electrode, used as a control. The SEM analysis of the damaged electrode revealed fissurations and crack-like forms of the outer jacket tubing, degeneration of the internal core and wires stretching. The EDX analysis permitted to appreciate an increase of chemical elements, especially sodium, suggesting an alteration of the electrode-brain interface. This study shows the qualitative and quantitative alterations of a malfunctioning electrode and, to reduce the rate of hardware-related complications, it suggests the development of more reliable polymers. PMID:23563791

Marras, Carlo; Rizzi, Michele; Ravagnan, Luca; De Benedictis, Alessandro; Zorzi, Giovanna; Bongiorno, Gero; Marchesi, Davide; Messina, Giuseppe; Cordella, Roberto; Franzini, Angelo

2013-04-06

202

Morphological and behavioral markers of environmentally induced retardation of brain development: an animal model  

SciTech Connect

In most neurotoxicological studies morphological assessment focuses on pathological effects, like degenerative changes in neuronal perikarya, axonopathy, demyelination, and glial and endothelial cell reactions. Similarly, the assessment of physiological and behavioral effects center on evident neurological symptoms, like EEG and EMG abnormalities, resting and intention tremor, abnormal gait, and abnormal reflexes. This paper reviews briefly another central nervous system target of harmful environmental agents, which results in behavioral abnormalities without any qualitatively evident neuropathology. This is called microneuronal hypoplasia, a retardation of brain development characterized by a quantitative reduction in the normal population of late-generated, short-axoned neurons in specific brain regions. Correlated descriptive and experimental neurogenetic studies in the rat have established that all the cerebellar granule cells and a very high proportion of hippocampal granule cells are produced postnatally, and that focal, low-dose X-irradiation either of the cerebellum or of the hippocampus after birth selectively interferes with the acquisition of the full complement of granule cells (microneuronal hypoplasia). Subsequent behavioral investigations showed that cerebellar microneuronal hypoplasia results in profound hyperactivity without motor abnormalities, while hippocampal microneuronal hypoplasia results in hyperactivity, as well as attentional and learning deficits. There is much indirect clinical evidence that various harmful environmental agents affecting the pregnant mother and/or the infant lead to such childhood disorders as hyperactivity and attentional and learning disorders. 109 references.

Altman, J.

1987-10-01

203

Peculiarity Oriented Multi-Aspect Brain Data Analysis for Studying Human Multi-Perception Mechanism  

Microsoft Academic Search

In order to investigate the structure of advanced human brain activities, various brain analysis methods are required. It has been observed that multiple brain data such as fMRI brain images and EEG brain waves extracted from human multi-perception mechanism involved in a particular task are peculiar ones with respect to the specific state or the relatedpart of a stimulus. Based

Ning Zhong; Shinichi Motomura; Jing-long Wu

2005-01-01

204

Regional Patterns of Gene Expression in Human and Chimpanzee Brains  

Microsoft Academic Search

We have analyzed gene expression in various brain regions of humans and chimpanzees. Within both human and chimpanzee individuals, the transcriptomes of the cerebral cortex are very similar to each other and differ more between individuals than among regions within an individual. In contrast, the transcriptomes of the cerebral cortex, the caudate nucleus, and the cerebellum differ substantially from each

Philipp Khaitovich; Bjoern Muetzel; Xinwei She; Michael Lachmann; Ines Hellmann; Janko Dietzsch; Stephan Steigele; Hong-Hai Do; Gunter Weiss; Wolfgang Enard; Florian Heissig; Thomas Arendt; Kay Nieselt-Struwe; Evan E. Eichler; Svante Paabo

2004-01-01

205

Shortcomings of the Human Brain and Remedial Action by Religion  

ERIC Educational Resources Information Center

|There is no consensus as to whether, and if so, in which regard and to what extent science and religion is needed for human survival. Here a circumscribed domain is taken up: the sovereignty and sufficiency of the human brain in this context. Several of its shortcomings are pointed out. Religion and other aspects of culture are needed for…

Reich, K. Helmut

2010-01-01

206

Metabolic changes in schizophrenia and human brain evolution  

PubMed Central

Background Despite decades of research, the molecular changes responsible for the evolution of human cognitive abilities remain unknown. Comparative evolutionary studies provide detailed information about DNA sequence and mRNA expression differences between humans and other primates but, in the absence of other information, it has proved very difficult to identify molecular pathways relevant to human cognition. Results Here, we compare changes in gene expression and metabolite concentrations in the human brain and compare them to the changes seen in a disorder known to affect human cognitive abilities, schizophrenia. We find that both genes and metabolites relating to energy metabolism and energy-expensive brain functions are altered in schizophrenia and, at the same time, appear to have changed rapidly during recent human evolution, probably as a result of positive selection. Conclusion Our findings, along with several previous studies, suggest that the evolution of human cognitive abilities was accompanied by adaptive changes in brain metabolism, potentially pushing the human brain to the limit of its metabolic capabilities.

Khaitovich, Philipp; Lockstone, Helen E; Wayland, Matthew T; Tsang, Tsz M; Jayatilaka, Samantha D; Guo, Arfu J; Zhou, Jie; Somel, Mehmet; Harris, Laura W; Holmes, Elaine; Paabo, Svante; Bahn, Sabine

2008-01-01

207

Persistent Poliovirus Infection of Human Fetal Brain Cells  

Microsoft Academic Search

It has been suggested that poliovirus (PV), the causative agent of poliomyelitis, could persist in surviving patients. We have previously shown that PV can persistently infect some human cell lines in vitro, particularly neuroblastoma cell lines. We report here an ex vivo model in which PV can persistently infect primary cultures of human fetal brain cells. Two mutations involving capsid

NICOLE PAVIO; MARIE-HELENE BUC-CARON; ANDFLORENCE COLBERE-GARAPIN

1996-01-01

208

Descriptive Analysis and Quantification of Angiogenesis in Human Brain Tumors  

Microsoft Academic Search

Quantitative determination of the degree of vascularity has been shown to be independently prognostically significant in many human tumor types. In particular, tumor vascularity has known importance in astrocytomas, in which endothelial proliferation is a criterion for anaplasia in many grading schemes. This review analyzes reports of microvessel quantification performed on histologic sections of human brain tumors, and in which

Rebecca D. Folkerth

2000-01-01

209

Human cadaver brain infusion model for neurosurgical training  

Microsoft Academic Search

BackgroundMicroneurosurgical technique and anatomical knowledge require extensive laboratory training before mastering these skills. There are diverse training models based on synthetic materials, anesthetized animals, cadaver animals, or human cadaver. Human cadaver models are especially beneficial because they are the closest to live surgery with the greatest disadvantage of lacking hemodynamic factors. We developed the “brain infusion model” to provide a

Jon Olabe; Javier Olabe; Vidal Sancho

2009-01-01

210

Conservation of Regional Gene Expression in Mouse and Human Brain  

PubMed Central

Many neurodegenerative diseases have a hallmark regional and cellular pathology. Gene expression analysis of healthy tissues may provide clues to the differences that distinguish resistant and sensitive tissues and cell types. Comparative analysis of gene expression in healthy mouse and human brain provides a framework to explore the ability of mice to model diseases of the human brain. It may also aid in understanding brain evolution and the basis for higher order cognitive abilities. Here we compare gene expression profiles of human motor cortex, caudate nucleus, and cerebellum to one another and identify genes that are more highly expressed in one region relative to another. We separately perform identical analysis on corresponding brain regions from mice. Within each species, we find that the different brain regions have distinctly different expression profiles. Contrasting between the two species shows that regionally enriched genes in one species are generally regionally enriched genes in the other species. Thus, even when considering thousands of genes, the expression ratios in two regions from one species are significantly correlated with expression ratios in the other species. Finally, genes whose expression is higher in one area of the brain relative to the other areas, in other words genes with patterned expression, tend to have greater conservation of nucleotide sequence than more widely expressed genes. Together these observations suggest that region-specific genes have been conserved in the mammalian brain at both the sequence and gene expression levels. Given the general similarity between patterns of gene expression in healthy human and mouse brains, we believe it is reasonable to expect a high degree of concordance between microarray phenotypes of human neurodegenerative diseases and their mouse models. Finally, these data on very divergent species provide context for studies in more closely related species that address questions such as the origins of cognitive differences.

Strand, Andrew D; Aragaki, Aaron K; Baquet, Zachary C; Hodges, Angela; Cunningham, Philip; Holmans, Peter; Jones, Kevin R; Jones, Lesley; Kooperberg, Charles; Olson, James M

2007-01-01

211

Morphological evidence of marine adaptations in human kidneys.  

PubMed

Amongst primates, kidneys normally exhibiting lobulated, multipyramidal, medullas is a unique attribute of the human species. Although, kidneys naturally multipyramidal in their medullary morphology are rare in terrestrial mammals, kidneys with lobulated medullas do occur in: elephants, bears, rhinoceroses, bison, cattle, pigs, and the okapi. However, kidneys characterized with multipyramidal medullas are common in aquatic mammals and are nearly universal in marine mammals. To avoid the deleterious effects of saline water dehydration, marine mammals have adaptively thickened the medullas of their kidneys--which enhances their ability to concentrate excretory salts in the urine. However, the lobulation of the kidney's medullary region in marine mammals appears to be an adaptation to expand the surface area between the medulla and the enveloping outer cortex in order to increase the volume of marine dietary induced hypertonic plasma that can be immediately processed for the excretion of excess salts and nitrogenous waste. A phylogenetic review of freshwater aquatic mammals suggest that most, if not all, nonmarine aquatic mammals inherited the medullary pyramids of their kidneys from ancestors who originally inhabited, or frequented, marine environments. So this suggest that most, if not all, aquatic mammals exhibiting kidneys with lobulated medullas are either marine adapted--or are descended from marine antecedents. Additionally, a phylogenetic review of nonhuman terrestrial mammals possessing kidneys with multipyramidal medullas suggest that bears, elephants and possibly rhinoceroses, also, inherited their lobulated medullas from semiaquatic marine ancestors. The fact that several terrestrial mammalian species of semiaquatic marine ancestry exhibit kidneys with multipyramidal medullas, may suggest that humans could have, also, inherited the lobulated medullas of their kidneys from coastal marine ancestors. And a specialized marine diet in ancient human ancestry could, also, explain the reactivation and enumeration of corporeal eccrine sweat glands and the copious secretion of salt tears. The substantial loss of genetic variation in humans relative to other hominoid primates, combined with the apparent isolation of early Pliocene human ancestors from particular retroviruses that infected all other African primate species, may suggest that such a semiaquatic marine phase, during the emergence of Homo, may have occurred on an island off the coast of Africa during the early Pliocene. PMID:16263222

Williams, Marcel F

2005-11-02

212

Exploring the Origins of the Human Brain through Molecular Evolution  

PubMed Central

The emergence of the human brain is one of evolution’s most compelling mysteries. With its singular importance and astounding complexity, understanding the forces that gave rise to the human brain is a major undertaking. Recently, the identification and publication of the complete genomic sequence of humans, mice, chimpanzees, and macaques has allowed for large-scale studies looking for the genic substrates of this natural selection. These investigations into positive selection, however, have generally produced incongruous results. Here we consider some of these studies and their differences in methodologies with an eye towards how they affect the results. We also clarify the strengths and weaknesses of each of these approaches and discuss how these can be synthesized to develop a more complete understanding of the genetic correlates behind the human brain and the selective events that have acted upon them.

Vallender, Eric J.

2009-01-01

213

A Category Theory Model for Learning and Memory of the Human Brain  

Microsoft Academic Search

Learning and memory, which are important functions of the human brain, are the foundations of thinking. Revealing the learning and memory mechanism of human brain is the core objective and main development way of the intelligent science. Improved human brain functional structure model, a memory prediction structural framework on the brain structure and function are proposed. And then we work

Pan Hong-jun; Yao Xiao-qiu; Qi Chang-song; Chen Hong-tao

2010-01-01

214

Isolation and characterization of ganglioside GMlb from normal human brain  

Microsoft Academic Search

Abatract A sialidase-susceptible monosialoganglioside was iso- lated from normal human brain by DEAE-SePhadex A-25 and side was about 6 mg per whole brain. Its structure was eluci- dated by sugar analysis, sialidase digestion, permethylation, and proton NMR studies. This ganglioside had carbohydrate, fatty acid, and long-chain base compositions identical to those of preliminary data for the presence of this ganglioside

Toshio Ariga; Robert K. Yu

215

Evolutionary and ecological aspects of early brain malnutrition in humans  

Microsoft Academic Search

This article reviews the effects of malnutrition on early brain development using data generated from animal experiments and\\u000a human clinical studies. Three related processes, each with their own functional consequences, are implicated in the alteration\\u000a of brain development. (1) Maternal undernutrition at the start of pregnancy results in reduced transfer of nutrients across\\u000a the placenta, allowing the conservation of effort

William D. Lukas; Benjamin C. Campbell

2000-01-01

216

The lipopigments in human brain tissue necroses  

Microsoft Academic Search

The ceroid pigment of macrophages were subdivided into four different types according to their own color and their ability to stain with luxol fast blue. With reference to this mode a series of more than 200 brain infarcts which had happened 1 day to 56 years before death, was examined systematically. According to the results the ceroid variants do not

R. Schröder

1980-01-01

217

Anatomical evolution and the human brain  

Microsoft Academic Search

For many reasons it is a great pleasure and an honor for me to be invited to appear before you this evening. Some of the reasons are trivial, but others are perhaps of more significance. I particularly welcome the opportunity to speak on an aspect of the function of the brain that was of great concern to Dr. Samuel Orton,

Norman Geschwind

1972-01-01

218

Morphology and some biomechanical properties of human liver and spleen.  

PubMed

The aim of the study was an experimental determination of some morphological and mechanical properties of human liver and spleen (amount of collagen in organ capsules, their critical tension and density), followed by a definition of the threshold of critical acceleration, above which the organs can be injured during a car crash. Experiments were done on 33 fresh cadavers (18 males, 15 females; age 3 months to 88 years), and completed by sled tests on dummies testing the loads of both hypochondrial regions protected by air bags and/or seat belts. Results obtained were the following: (1). liver: capsule collagen 14-35%, critical tension 0.066-0.386 MPa, density 0.92-1.19 g/ml, critical acceleration 48-155 g; (2). spleen: capsule collagen 1.8-24.4%, critical tension 0.022-0.652 MPa, density 0.85-1.25 g/ml, critical acceleration 33-149 g. Loads of both hypochondrial regions measured on dummies during a predefined sled test were 34-67 g. Results obtained were evaluated qualitatively and discussed from the point of view of their possible use in future passive safety engineering and design calculations. PMID:12497218

Stingl, J; Bá?a, V; Cech, P; Kovanda, J; Kovandová, H; Mandys, V; Rejmontová, J; Sosna, B

2002-11-07

219

Morphology of root canals in lower human premolars  

PubMed Central

Background The knowledge of the root canal morphology and the possible anatomical variations of mandibular premolars are important for the successful endodontic treatment of such cases. The aim of this study was to investigate the presence of two or three root canals in extracted first and second mandibular premolars which were collected from health centers in Syria. Materials and Methods: One hundred and ten human mandibular premolars (70 first premolars and 40 second premolars) with fully developed roots were investigated. After access the cavity of the teeth, the root canals were explored and radiographs were taken. Results: Premolars with one canal were found in 87% of cases (53% first premolar and 34% second premolar) and premolars with two canals were found in 12% of cases (10% first premolar and 2% second premolar). There was just one case (1%) where a first premolar had three canals. These differences were statistically significant with P<0.05. Conclusion: Clinicians should be aware of the anatomical variation in the mandibular premolars and be able to apply this knowledge in radiographical and clinical interpretation.

Baroudi, Kusai; Kazkaz, Mulham; Sakka, Salah; Tarakji, Bassel

2012-01-01

220

Immunohistochemical localization of oxytocin receptors in human brain.  

PubMed

The neuropeptide oxytocin (OT) regulates rodent, primate and human social behaviors and stress responses. OT binding studies employing (125)I-d(CH2)5-[Tyr(Me)2,Thr4,Tyr-NH2(9)] ornithine vasotocin ((125)I-OTA), has been used to locate and quantify OT receptors (OTRs) in numerous areas of the rat brain. This ligand has also been applied to locating OTRs in the human brain. The results of the latter studies, however, have been brought into question because of subsequent evidence that (125)I-OTA is much less selective for OTR vs. vasopressin receptors in the primate brain. Previously we used a monoclonal antibody directed toward a region of the human OTR to demonstrate selective immunostaining of cell bodies and fibers in the preoptic-anterior hypothalamic area and ventral septum of a cynomolgus monkey (Boccia et al., 2001). The present study employed the same monoclonal antibody to study the location of OTRs in tissue blocks containing cortical, limbic and brainstem areas dissected from fixed adult, human female brains. OTRs were visualized in discrete cell bodies and/or fibers in the central and basolateral regions of the amygdala, medial preoptic area (MPOA), anterior and ventromedial hypothalamus, olfactory nucleus, vertical limb of the diagonal band, ventrolateral septum, anterior cingulate and hypoglossal and solitary nuclei. OTR staining was not observed in the hippocampus (including CA2 and CA3), parietal cortex, raphe nucleus, nucleus ambiguus or pons. These results suggest that there are some similarities, but also important differences, in the locations of OTRs in human and rodent brains. Immunohistochemistry (IHC) utilizing a monoclonal antibody provides specific localization of OTRs in the human brain and thereby provides opportunity to further study OTR in human development and psychiatric conditions. PMID:24012742

Boccia, M L; Petrusz, P; Suzuki, K; Marson, L; Pedersen, C A

2013-09-04

221

Misuse of prescription stimulants among college students: A review of the literature and implications for morphological and cognitive effects on brain functioning.  

PubMed

Prescription stimulant medication, the most frequently recommended treatment for college students with attention deficit/hyperactivity disorder (ADHD), has become increasingly available on college campuses. Research investigating prescription stimulant misuse among college students indicates that significant numbers of students without ADHD are taking prescription stimulants to enhance their cognitive performance. This article systematically reviews studies concerning misuse of prescription stimulants among college students with and without ADHD as well as the cognitive and morphological brain changes associated with prescription stimulants in humans and other animals. Whether these morphological changes are accompanied by improved cognitive performance remains equivocal. Implications of this body of literature are discussed and suggestions for future research are advanced. (PsycINFO Database Record (c) 2013 APA, all rights reserved). PMID:24099359

Weyandt, Lisa L; Marraccini, Marisa E; Gudmundsdottir, Bergljot Gyda; Zavras, Brynheld Martinez; Turcotte, Kyle D; Munro, Bailey A; Amoroso, Alex J

2013-10-01

222

Electrophysiological signatures of resting state networks in the human brain  

PubMed Central

Functional neuroimaging and electrophysiological studies have documented a dynamic baseline of intrinsic (not stimulus- or task-evoked) brain activity during resting wakefulness. This baseline is characterized by slow (<0.1 Hz) fluctuations of functional imaging signals that are topographically organized in discrete brain networks, and by much faster (1–80 Hz) electrical oscillations. To investigate the relationship between hemodynamic and electrical oscillations, we have adopted a completely data-driven approach that combines information from simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI). Using independent component analysis on the fMRI data, we identified six widely distributed resting state networks. The blood oxygenation level-dependent signal fluctuations associated with each network were correlated with the EEG power variations of delta, theta, alpha, beta, and gamma rhythms. Each functional network was characterized by a specific electrophysiological signature that involved the combination of different brain rhythms. Moreover, the joint EEG/fMRI analysis afforded a finer physiological fractionation of brain networks in the resting human brain. This result supports for the first time in humans the coalescence of several brain rhythms within large-scale brain networks as suggested by biophysical studies.

Mantini, D.; Perrucci, M. G.; Del Gratta, C.; Romani, G. L.; Corbetta, M.

2007-01-01

223

Serotonin transporter knockout and repeated social defeat stress: impact on neuronal morphology and plasticity in limbic brain areas.  

PubMed

Low expression of the human serotonin transporter (5-HTT) gene presumably interacts with stressful life events enhancing susceptibility for affective disorders. 5-Htt knockout (KO) mice display an anxious phenotype, and behavioural differences compared to wild-type (WT) mice are exacerbated after repeated loser experience in a resident-intruder stress paradigm. To assess whether genotype-dependent and stress-induced behavioural differences are reflected in alterations of neuronal morphology in limbic areas, we studied dendritic length and complexity of pyramidal neurons in the anterior cingulate and infralimbic cortices (CG, IL), hippocampus CA1 region, and of pyramidal neurons and interneurons in the lateral (La) and basolateral (BL) amygdaloid nuclei in Golgi-Cox-stained brains of male WT and 5-Htt KO control and loser mice. Spine density was analysed for IL apical and amygdaloid apical and basal pyramidal neuron dendrites. While group differences were absent for parameters analysed in CG, CA1 and amygdaloid interneurons, pyramidal neurons in the IL displayed tendencies to shorter and less spinous distal apical dendrites in 5-Htt KO controls, and to extended proximal dendrites in WT losers compared to WT controls. In contrast, spine density of several dendritic compartments of amygdaloid pyramids was significantly higher in 5-Htt KO mice compared to WT controls. While a tendency to increased spine density was observed in the same dendritic compartments in WT after stress, changes were lacking in stressed compared to control 5-Htt KO mice. Our findings indicate that disturbed 5-HT homeostasis results in alterations of limbic neuronal morphology, especially in higher spinogenesis in amygdaloid pyramidal neurons. Social stress leads to similar but less pronounced changes in the WT, and neuroplasticity upon stress is reduced in 5-Htt KO mice. PMID:21238500

Nietzer, S L; Bonn, M; Jansen, F; Heiming, R S; Lewejohann, L; Sachser, N; Asan, E S; Lesch, K P; Schmitt, A G

2011-01-14

224

Toward discovery science of human brain function.  

PubMed

Although it is being successfully implemented for exploration of the genome, discovery science has eluded the functional neuroimaging community. The core challenge remains the development of common paradigms for interrogating the myriad functional systems in the brain without the constraints of a priori hypotheses. Resting-state functional MRI (R-fMRI) constitutes a candidate approach capable of addressing this challenge. Imaging the brain during rest reveals large-amplitude spontaneous low-frequency (<0.1 Hz) fluctuations in the fMRI signal that are temporally correlated across functionally related areas. Referred to as functional connectivity, these correlations yield detailed maps of complex neural systems, collectively constituting an individual's "functional connectome." Reproducibility across datasets and individuals suggests the functional connectome has a common architecture, yet each individual's functional connectome exhibits unique features, with stable, meaningful interindividual differences in connectivity patterns and strengths. Comprehensive mapping of the functional connectome, and its subsequent exploitation to discern genetic influences and brain-behavior relationships, will require multicenter collaborative datasets. Here we initiate this endeavor by gathering R-fMRI data from 1,414 volunteers collected independently at 35 international centers. We demonstrate a universal architecture of positive and negative functional connections, as well as consistent loci of inter-individual variability. Age and sex emerged as significant determinants. These results demonstrate that independent R-fMRI datasets can be aggregated and shared. High-throughput R-fMRI can provide quantitative phenotypes for molecular genetic studies and biomarkers of developmental and pathological processes in the brain. To initiate discovery science of brain function, the 1000 Functional Connectomes Project dataset is freely accessible at www.nitrc.org/projects/fcon_1000/. PMID:20176931

Biswal, Bharat B; Mennes, Maarten; Zuo, Xi-Nian; Gohel, Suril; Kelly, Clare; Smith, Steve M; Beckmann, Christian F; Adelstein, Jonathan S; Buckner, Randy L; Colcombe, Stan; Dogonowski, Anne-Marie; Ernst, Monique; Fair, Damien; Hampson, Michelle; Hoptman, Matthew J; Hyde, James S; Kiviniemi, Vesa J; Kötter, Rolf; Li, Shi-Jiang; Lin, Ching-Po; Lowe, Mark J; Mackay, Clare; Madden, David J; Madsen, Kristoffer H; Margulies, Daniel S; Mayberg, Helen S; McMahon, Katie; Monk, Christopher S; Mostofsky, Stewart H; Nagel, Bonnie J; Pekar, James J; Peltier, Scott J; Petersen, Steven E; Riedl, Valentin; Rombouts, Serge A R B; Rypma, Bart; Schlaggar, Bradley L; Schmidt, Sein; Seidler, Rachael D; Siegle, Greg J; Sorg, Christian; Teng, Gao-Jun; Veijola, Juha; Villringer, Arno; Walter, Martin; Wang, Lihong; Weng, Xu-Chu; Whitfield-Gabrieli, Susan; Williamson, Peter; Windischberger, Christian; Zang, Yu-Feng; Zhang, Hong-Ying; Castellanos, F Xavier; Milham, Michael P

2010-02-22

225

Toward discovery science of human brain function  

PubMed Central

Although it is being successfully implemented for exploration of the genome, discovery science has eluded the functional neuroimaging community. The core challenge remains the development of common paradigms for interrogating the myriad functional systems in the brain without the constraints of a priori hypotheses. Resting-state functional MRI (R-fMRI) constitutes a candidate approach capable of addressing this challenge. Imaging the brain during rest reveals large-amplitude spontaneous low-frequency (<0.1 Hz) fluctuations in the fMRI signal that are temporally correlated across functionally related areas. Referred to as functional connectivity, these correlations yield detailed maps of complex neural systems, collectively constituting an individual's “functional connectome.” Reproducibility across datasets and individuals suggests the functional connectome has a common architecture, yet each individual's functional connectome exhibits unique features, with stable, meaningful interindividual differences in connectivity patterns and strengths. Comprehensive mapping of the functional connectome, and its subsequent exploitation to discern genetic influences and brain–behavior relationships, will require multicenter collaborative datasets. Here we initiate this endeavor by gathering R-fMRI data from 1,414 volunteers collected independently at 35 international centers. We demonstrate a universal architecture of positive and negative functional connections, as well as consistent loci of inter-individual variability. Age and sex emerged as significant determinants. These results demonstrate that independent R-fMRI datasets can be aggregated and shared. High-throughput R-fMRI can provide quantitative phenotypes for molecular genetic studies and biomarkers of developmental and pathological processes in the brain. To initiate discovery science of brain function, the 1000 Functional Connectomes Project dataset is freely accessible at www.nitrc.org/projects/fcon_1000/.

Biswal, Bharat B.; Mennes, Maarten; Zuo, Xi-Nian; Gohel, Suril; Kelly, Clare; Smith, Steve M.; Beckmann, Christian F.; Adelstein, Jonathan S.; Buckner, Randy L.; Colcombe, Stan; Dogonowski, Anne-Marie; Ernst, Monique; Fair, Damien; Hampson, Michelle; Hoptman, Matthew J.; Hyde, James S.; Kiviniemi, Vesa J.; Kotter, Rolf; Li, Shi-Jiang; Lin, Ching-Po; Lowe, Mark J.; Mackay, Clare; Madden, David J.; Madsen, Kristoffer H.; Margulies, Daniel S.; Mayberg, Helen S.; McMahon, Katie; Monk, Christopher S.; Mostofsky, Stewart H.; Nagel, Bonnie J.; Pekar, James J.; Peltier, Scott J.; Petersen, Steven E.; Riedl, Valentin; Rombouts, Serge A. R. B.; Rypma, Bart; Schlaggar, Bradley L.; Schmidt, Sein; Seidler, Rachael D.; Siegle, Greg J.; Sorg, Christian; Teng, Gao-Jun; Veijola, Juha; Villringer, Arno; Walter, Martin; Wang, Lihong; Weng, Xu-Chu; Whitfield-Gabrieli, Susan; Williamson, Peter; Windischberger, Christian; Zang, Yu-Feng; Zhang, Hong-Ying; Castellanos, F. Xavier; Milham, Michael P.

2010-01-01

226

Infrasounds and biorhythms of the human brain  

Microsoft Academic Search

Low Frequency Noise (LFN) and infrasound has begun a new public health hazard. Evaluations of annoyance of (LFN) on human occupational health were based on standards where reactions of human auditory system and vibrations of parts of human body were small. Significant sensitivity has been observed on the central nervous system from infrasonic waves especially below 10 Hz. Observed follow-up

Ryszard Panuszka; Zbigniew Damijan; Cezary Kasprzak; James McGlothlin

2002-01-01

227

Nuclear magnetic resonance imaging and spectroscopy of human brain function.  

PubMed Central

The techniques of in vivo magnetic resonance (MR) imaging and spectroscopy have been established over the past two decades. Recent applications of these methods to study human brain function have become a rapidly growing area of research. The development of methods using standard MR contrast agents within the cerebral vasculature has allowed measurements of regional cerebral blood volume (rCBV), which are activity dependent. Subsequent investigations linked the MR relaxation properties of brain tissue to blood oxygenation levels which are also modulated by consumption and blood flow (rCBF). These methods have allowed mapping of brain activity in human visual and motor cortex as well as in areas of the frontal lobe involved in language. The methods have high enough spatial and temporal sensitivity to be used in individual subjects. MR spectroscopy of proton and carbon-13 nuclei has been used to measure rates of glucose transport and metabolism in the human brain. The steady-state measurements of brain glucose concentrations can be used to monitor the glycolytic flux, whereas subsequent glucose metabolism--i.e., the flux into the cerebral glutamate pool--can be used to measure tricarboxylic acid cycle flux. Under visual stimulation the concentration of lactate in the visual cortex has been shown to increase by MR spectroscopy. This increase is compatible with an increase of anaerobic glycolysis under these conditions as earlier proposed from positron emission tomography studies. It is shown how MR spectroscopy can extend this understanding of brain metabolism. Images Fig. 1 Fig. 2 Fig. 3

Shulman, R G; Blamire, A M; Rothman, D L; McCarthy, G

1993-01-01

228

Elevated gene expression levels distinguish human from non-human primate brains  

PubMed Central

Little is known about how the human brain differs from that of our closest relatives. To investigate the genetic basis of human specializations in brain organization and cognition, we compared gene expression profiles for the cerebral cortex of humans, chimpanzees, and rhesus macaques by using several independent techniques. We identified 169 genes that exhibited expression differences between human and chimpanzee cortex, and 91 were ascribed to the human lineage by using macaques as an outgroup. Surprisingly, most differences between the brains of humans and non-human primates involved up-regulation, with ?90% of the genes being more highly expressed in humans. By contrast, in the comparison of human and chimpanzee heart and liver, the numbers of up- and down-regulated genes were nearly identical. Our results indicate that the human brain displays a distinctive pattern of gene expression relative to non-human primates, with higher expression levels for many genes belonging to a wide variety of functional classes. The increased expression of these genes could provide the basis for extensive modifications of cerebral physiology and function in humans and suggests that the human brain is characterized by elevated levels of neuronal activity.

Caceres, Mario; Lachuer, Joel; Zapala, Matthew A.; Redmond, John C.; Kudo, Lili; Geschwind, Daniel H.; Lockhart, David J.; Preuss, Todd M.; Barlow, Carrolee

2003-01-01

229

A Bayesian approach to determining connectivity of the human brain.  

PubMed

Recent work regarding the analysis of brain imaging data has focused on examining functional and effective connectivity of the brain. We develop a novel descriptive and inferential method to analyze the connectivity of the human brain using functional MRI (fMRI). We assess the relationship between pairs of distinct brain regions by comparing expected joint and marginal probabilities of elevated activity of voxel pairs through a Bayesian paradigm, which allows for the incorporation of previously known anatomical and functional information. We define the relationship between two distinct brain regions by measures of functional connectivity and ascendancy. After assessing the relationship between all pairs of brain voxels, we are able to construct hierarchical functional networks from any given brain region and assess significant functional connectivity and ascendancy in these networks. We illustrate the use of our connectivity analysis using data from an fMRI study of social cooperation among women who played an iterated "Prisoner's Dilemma" game. Our analysis reveals a functional network that includes the amygdala, anterior insula cortex, and anterior cingulate cortex, and another network that includes the ventral striatum, orbitofrontal cortex, and anterior insula. Our method can be used to develop causal brain networks for use with structural equation modeling and dynamic causal models. PMID:16092131

Patel, Rajan S; Bowman, F Dubois; Rilling, James K

2006-03-01

230

Staphylococcus massiliensis sp. nov., isolated from a human brain abscess.  

PubMed

Gram-positive, catalase-positive, coagulase-negative, non-motile, non-fermentative and novobiocin-susceptible cocci were isolated from a human brain abscess sample (strain 5402776(T)). This novel strain was analysed by a polyphasic taxonomic approach. The respiratory quinones detected were MK-7 (93 %) and MK-6 (7 %) and the major fatty acids were C(15 : 0) iso (60.5 %), C(17 : 0) iso (8.96 %) C(15 : 0) anteiso (7.93 %) and C(19 : 0) iso (6.78 %). The peptidoglycan type was A3alpha l-Lys-Gly(2-3)-l-Ser-Gly. Based on cellular morphology and biochemical criteria, the new isolate was assigned to the genus Staphylococcus, although it did not correspond to any recognized species. The G+C content of the DNA was 36.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparisons showed that the new isolate was most closely related to Staphylococcus piscifermentans, Staphylococcus condimenti, Staphylococcus carnosus subsp. carnosus, S. carnosus subsp. utilis and Staphylococcus simulans (97.7 %, 97.6 %, 97.6 %, 97.6 % and 96.5 % sequence similarity, respectively). Comparison of tuf, hsp60, rpoB, dnaJ and sodA gene sequences was also performed. In phylogenetic analysis inferred from tuf, dnaJ and rpoB gene sequence comparisons, strain 5402776(T) clustered with Staphylococcus pettenkoferi (93.7 %, 82.5 % and 89 % sequence similarity, respectively) and on phylogenetic analysis inferred from sodA gene sequence comparisons, it clustered with Staphylococcus chromogenes (82.8 %). On the basis of phenotypic and genotypic data, this isolate represents a novel species for which the name Staphylococcus massiliensis sp. nov. is proposed (type strain 5402776(T)=CCUG 55927(T)=CSUR P23(T)). PMID:19666814

Al Masalma, Mouhamad; Raoult, Didier; Roux, Véronique

2009-08-07

231

Decoding the visual and subjective contents of the human brain  

PubMed Central

The potential for human neuroimaging to read-out the detailed contents of a person’s mental state has yet to be fully explored. We investigated whether the perception of edge orientation, a fundamental visual feature, can be decoded from human brain activity measured with functional magnetic resonance imaging (fMRI). Using statistical algorithms to classify brain states, we found that ensemble fMRI signals in early visual areas could reliably predict on individual trials which of eight stimulus orientations the subject was seeing. Moreover, when subjects had to attend to one of two overlapping orthogonal gratings, feature-based attention strongly biased ensemble activity towards the attended orientation. These results demonstrate that fMRI activity patterns in early visual areas, including primary visual cortex (V1), contain detailed orientation information that can reliably predict subjective perception. Our approach provides a framework for the readout of fine-tuned representations in the human brain and their subjective contents.

Kamitani, Yukiyasu; Tong, Frank

2005-01-01

232

Glucose transporter of the human brain and blood-brain barrier  

SciTech Connect

We identified and characterized the glucose transporter in the human cerebral cortex, cerebral microvessels, and choroid plexus by specific D-glucose-displaceable (3H)cytochalasin B binding. The binding was saturable, with a dissociation constant less than 1 microM. Maximal binding capacity was approximately 7 pmol/mg protein in the cerebral cortex, approximately 42 pmol/mg protein in brain microvessels, and approximately 27 pmol/mg protein in the choroid plexus. Several hexoses displaced specific (3H)cytochalasin B binding to microvessels in a rank-order that correlated well with their known ability to cross the blood-brain barrier; the only exception was 2-deoxy-D-glucose, which had much higher affinity for the glucose transporter than the natural substrate, D-glucose. Irreversible photoaffinity labeling of the glucose transporter of microvessels with (3H)cytochalasin B, followed by solubilization and polyacrylamide gel electrophoresis, labeled a protein band with an average molecular weight of approximately 55,000. Monoclonal and polyclonal antibodies specific to the human erythrocyte glucose transporter immunocytochemically stained brain blood vessels and the few trapped erythrocytes in situ, with minimal staining of the neuropil. In the choroid plexus, blood vessels did not stain, but the epithelium reacted positively. We conclude that human brain microvessels are richly endowed with a glucose transport moiety similar in molecular weight and antigenic characteristics to that of human erythrocytes and brain microvessels of other mammalian species.

Kalaria, R.N.; Gravina, S.A.; Schmidley, J.W.; Perry, G.; Harik, S.I.

1988-12-01

233

The human blastocyst: morphology and human chorionic gonadotrophin secretion in vitro.  

PubMed

Micromanipulation of human oocytes and embryos has provided new opportunities for both the treatment of infertility and the preimplantation diagnosis of genetic disease. It is important to determine whether manipulated embryos develop normally in vitro, as an indication of their suitability for transfer. However, at present there is little information on the development of non-manipulated embryos in vitro for comparison. We have therefore monitored morphological changes and human chorionic gonadotrophin (HCG) secretion in 36 non-manipulated human embryos, including 26 blastocysts and 10 cavitating morulae, daily from day 3 to day 14 of culture. Hatching was observed in 10 (38.5%) blastocysts and five of these adhered to the culture dish and appeared viable until day 14. The secretion of HCG was first detected on day 8, peaked at day 10 (51.11 +/- 8.7 mIU/ml) and then declined but was still detectable in four blastocysts on day 14. There was no overall difference in HCG secretion by hatched blastocysts and those which remained within the zona. However, those hatched blastocysts which showed adherence had significantly increased (P less than 0.05) HCG secretion. For individual blastocysts, the pattern of HCG secretion correlated well with the assessment of morphology. These data provide the basis for comparative studies of morphological changes and HCG secretion in manipulated embryos. PMID:1806575

Dokras, A; Sargent, I L; Ross, C; Gardner, R L; Barlow, D H

1991-09-01

234

Sexual dimorphism in the human brain: evidence from neuroimaging.  

PubMed

In recent years, more and more emphasis has been placed on the investigation of sex differences in the human brain. Noninvasive neuroimaging techniques represent an essential tool in the effort to better understand the effects of sex on both brain structure and function. In this review, we provide a comprehensive summary of the findings that were collected in human neuroimaging studies in vivo thus far: we explore sexual dimorphism in the human brain at the level of (1) brain structure, in both gray and white matter, observed by voxel-based morphometry (VBM) and diffusion tensor imaging (DTI), respectively; (2) baseline neural activity, studied using resting-state functional magnetic resonance imaging (rs-fMRI) and positron emission tomography (PET); (3) neurochemistry, visualized by means of neuroreceptor ligand PET; and (4) task-related neural activation, investigated using fMRI. Functional MRI findings from the literature are complemented by our own meta-analysis of fMRI studies on sex-specific differences in human emotional processing. Specifically, we used activation likelihood estimation (ALE) to provide a quantitative approach to mapping the consistency of neural networks involved in emotional processing across studies. The presented evidence for sex-specific differences in neural structure and function highlights the importance of modeling sex as a contributing factor in the analysis of brain-related data. PMID:22921939

Sacher, Julia; Neumann, Jane; Okon-Singer, Hadas; Gotowiec, Sarah; Villringer, Arno

2012-08-22

235

Human-like brain hemispheric dominance in birdsong learning.  

PubMed

Unlike nonhuman primates, songbirds learn to vocalize very much like human infants acquire spoken language. In humans, Broca's area in the frontal lobe and Wernicke's area in the temporal lobe are crucially involved in speech production and perception, respectively. Songbirds have analogous brain regions that show a similar neural dissociation between vocal production and auditory perception and memory. In both humans and songbirds, there is evidence for lateralization of neural responsiveness in these brain regions. Human infants already show left-sided dominance in their brain activation when exposed to speech. Moreover, a memory-specific left-sided dominance in Wernicke's area for speech perception has been demonstrated in 2.5-mo-old babies. It is possible that auditory-vocal learning is associated with hemispheric dominance and that this association arose in songbirds and humans through convergent evolution. Therefore, we investigated whether there is similar song memory-related lateralization in the songbird brain. We exposed male zebra finches to tutor or unfamiliar song. We found left-sided dominance of neuronal activation in a Broca-like brain region (HVC, a letter-based name) of juvenile and adult zebra finch males, independent of the song stimulus presented. In addition, juvenile males showed left-sided dominance for tutor song but not for unfamiliar song in a Wernicke-like brain region (the caudomedial nidopallium). Thus, left-sided dominance in the caudomedial nidopallium was specific for the song-learning phase and was memory-related. These findings demonstrate a remarkable neural parallel between birdsong and human spoken language, and they have important consequences for our understanding of the evolution of auditory-vocal learning and its neural mechanisms. PMID:22802637

Moorman, Sanne; Gobes, Sharon M H; Kuijpers, Maaike; Kerkhofs, Amber; Zandbergen, Matthijs A; Bolhuis, Johan J

2012-07-16

236

Functional connectivity hubs in the human brain.  

PubMed

Brain networks appear to have few and well localized regions with high functional connectivity density (hubs) for fast integration of neural processing, and their dysfunction could contribute to neuropsychiatric diseases. However the variability in the distribution of these brain hubs is unknown due in part to the overwhelming computational demands associated to their localization. Recently we developed a fast algorithm to map the local functional connectivity density (lFCD). Here we extend our method to map the global density (gFDC) taking advantage of parallel computing. We mapped the gFCD in the brain of 1031 subjects from the 1000 Functional Connectomes project and show that the strongest hubs are located in regions of the default mode network (DMN) and in sensory cortices, whereas subcortical regions exhibited the weakest hubs. The strongest hubs were consistently located in ventral precuneus/cingulate gyrus (previously identified by other analytical methods including lFCD) and in primary visual cortex (BA 17/18), which highlights their centrality to resting connectivity networks. In contrast and after rescaling, hubs in prefrontal regions had lower gFCD than lFCD, which suggests that their local functional connectivity (as opposed to long-range connectivity) prevails in the resting state. The power scaling of the probability distribution of gFCD hubs (as for lFCD) was consistent across research centers further corroborating the "scale-free" topology of brain networks. Within and between-subject variability for gFCD were twice than that for lFCD (20% vs. 12% and 84% vs. 34%, respectively) suggesting that gFCD is more sensitive to individual differences in functional connectivity. PMID:21609769

Tomasi, Dardo; Volkow, Nora D

2011-05-14

237

Measuring dopamine release in the human brain with PET  

SciTech Connect

The dopamine system is involved in the regulation of brain regions that subserve motor, cognitive and motivational behaviors. Disruptions of dopamine (DA) function have ben implicated in neurological and psychiatric illnesses including substance abuse as well as on some of the deficits associated with aging of the human brain. This has made the DA system an important topic in research in the neurosciences and neuroimaging as well as an important molecular target for drug development. Positron Emission Tomography (PET), was the first technology that enabled direct measurement of components of the DA system in the living human brain. Imaging studies of DA in the living brain have been indirect, relying on the development of radiotracers to label DA receptors, DA transporters, compounds which have specificity for the enzymes which degrade synaptic DA. Additionally, through the use of tracers that provide information on regional brain activity (ie brain glucose metabolism and cerebral blood flow) and of appropriate pharmacological interventions, it has been possible to assess the functional consequences of changes in brain DA activity. DA specific ligands have been useful in the evaluation of patients with neuropsychiatric illnesses as well as to investigate receptor blockade by antipsychotic drugs. A limitation of strategies that rely on the use of DA specific ligands is that the measures do not necessarily reflect the functional state of the dopaminergic system and that there use to study the effects of drugs is limited to the investigation of receptor or transporter occupancy. Newer strategies have been developed in an attempt to provide with information on dopamine release and on the functional responsivity of the DA system in the human brain. This in turn allows to investigate the effects of pharmacological agent in an analogous way to what is done with microdialysis techniques.

Volkow, N.D. [Brookhaven National Lab., Upton, NY (United States)]|[State Univ. of New York at Stony Brook, Stony Brook, NY (United States). Dept. of Psychiatry; Fowler, J.S.; Logan, J.; Wang, G.J. [Brookhaven National Lab., Upton, NY (United States)

1995-12-01

238

Human brain spots emotion in non humanoid robots.  

PubMed

The computation by which our brain elaborates fast responses to emotional expressions is currently an active field of brain studies. Previous studies have focused on stimuli taken from everyday life. Here, we investigated event-related potentials in response to happy vs neutral stimuli of human and non-humanoid robots. At the behavioural level, emotion shortened reaction times similarly for robotic and human stimuli. Early P1 wave was enhanced in response to happy compared to neutral expressions for robotic as well as for human stimuli, suggesting that emotion from robots is encoded as early as human emotion expression. Congruent with their lower faceness properties compared to human stimuli, robots elicited a later and lower N170 component than human stimuli. These findings challenge the claim that robots need to present an anthropomorphic aspect to interact with humans. Taken together, such results suggest that the early brain processing of emotional expressions is not bounded to human-like arrangements embodying emotion. PMID:20194513

Dubal, Stéphanie; Foucher, Aurélie; Jouvent, Roland; Nadel, Jacqueline

2010-03-01

239

Compact continuum brain model for human electroencephalogram  

NASA Astrophysics Data System (ADS)

A low-dimensional, compact brain model has recently been developed based on physiologically based mean-field continuum formulation of electric activity of the brain. The essential feature of the new compact model is a second order time-delayed differential equation that has physiologically plausible terms, such as rapid corticocortical feedback and delayed feedback via extracortical pathways. Due to its compact form, the model facilitates insight into complex brain dynamics via standard linear and nonlinear techniques. The model successfully reproduces many features of previous models and experiments. For example, experimentally observed typical rhythms of electroencephalogram (EEG) signals are reproduced in a physiologically plausible parameter region. In the nonlinear regime, onsets of seizures, which often develop into limit cycles, are illustrated by modulating model parameters. It is also shown that a hysteresis can occur when the system has multiple attractors. As a further illustration of this approach, power spectra of the model are fitted to those of sleep EEGs of two subjects (one with apnea, the other with narcolepsy). The model parameters obtained from the fittings show good matches with previous literature. Our results suggest that the compact model can provide a theoretical basis for analyzing complex EEG signals.

Kim, J. W.; Shin, H.-B.; Robinson, P. A.

2007-12-01

240

Fundamental dynamical modes underlying human brain synchronization.  

PubMed

Little is known about the long-term dynamics of widely interacting cortical and subcortical networks during the wake-sleep cycle. Using large-scale intracranial recordings of epileptic patients during seizure-free periods, we investigated local- and long-range synchronization between multiple brain regions over several days. For such high-dimensional data, summary information is required for understanding and modelling the underlying dynamics. Here, we suggest that a compact yet useful representation is given by a state space based on the first principal components. Using this representation, we report, with a remarkable similarity across the patients with different locations of electrode placement, that the seemingly complex patterns of brain synchrony during the wake-sleep cycle can be represented by a small number of characteristic dynamic modes. In this space, transitions between behavioral states occur through specific trajectories from one mode to another. These findings suggest that, at a coarse level of temporal resolution, the different brain states are correlated with several dominant synchrony patterns which are successively activated across wake-sleep states. PMID:22811753

Alvarado-Rojas, Catalina; Le Van Quyen, Michel

2012-06-28

241

Mu opioid receptor binding sites in human brain  

SciTech Connect

Our experiments focused on the examination of the distribution of mu opioid receptor binding sites in normal human brain using the highly selective ligand (/sup 3/H)DAGO, in both membrane binding assay and in vitro receptor autoradiography. Mu opioid binding sites are very discretely distributed in human brain with high densities of sites found in the posterior amygdala, caudate, putamen, hypothalamus and certain cortical areas. Moreover the autoradiographic distribution of (/sup 3/H)DAGO binding sites clearly reveals the discrete lamination (layers I and III-IV) of mu sites in cortical areas.

Pilapil, C.; Welner, S.; Magnan, J.; Zamir, N.; Quirion, R.

1986-01-01

242

Optical dosimetry in photodynamic therapy of human uterus and brain  

NASA Astrophysics Data System (ADS)

Optical 'dose' is one of the fundamental parameters required in the design of an efficacious regimen of photodynamic therapy (PDT). The issues involved in delivering a sufficient optical dose to the human uterus and brain during PDT will be discussed. Specifically, measurements of optical properties and fluence rates in excised human uteri are presented. Measured fluence rates are compared to the predictions of a simple diffusion model and the clinical utility of the treatment is discussed. The delivery of light to brain tissue via a surgically implanted balloon applicator will also be considered. The time required to deliver and adequate dose is calculated based on known optical properties and diffusion theory.

Madsen, Steen J.; Svaasand, Lars O.; Hirschberg, Henry; Tadir, Yona; Tromberg, Bruce J.

1999-06-01

243

Simplified detection system for neuroreceptor studies in the human brain  

SciTech Connect

A simple, inexpensive dual-detector system has been developed for measurement of positronemitting receptor-binding drugs in the human brain. This high efficiency coincidence counting system requires that only a few hundred microcuries of labeled drug be administered to the subject, thereby allowing for multiple studies without an excessive radiation dose. Measurement of the binding of (11C)carfentanil, a high affinity synthetic opiate, to opiate receptors in the presence and in the absence of a competitive opiate antagonist indicates the potential utility of this system for estimating different degrees of receptor occupation in the human brain.

Bice, A.N.; Wagner, H.N. Jr.; Frost, J.J.; Natarajan, T.K.; Lee, M.C.; Wong, D.F.; Dannals, R.F.; Ravert, H.T.; Wilson, A.A.; Links, J.M.

1986-02-01

244

A four-dimensional probabilistic atlas of the human brain  

Microsoft Academic Search

Abstract,The authors,describe the development,of a four-dimensional,atlas and,reference system that includes,both macroscopic,and microscopic,information,on structure and function,of the human,brain in persons,between,the ages of 18 and,90 years. Given the presumed,large but previously,unquantified degree of structural and functional variance among normal persons in the human population, the basis for this atlas and,reference system,is probabilistic. Through,the efforts of the International Consortium,for Brain Mapping (ICBM), 7,000

J. C Mazziotta; A. Toga; A. Evans; P. Fox; J. Lancaster; K. Zilles; R. Woods; T. Paus; G. Simpson; B. Pike; C. Holmes; L. Collins; P. Thompson; D. MacDonald; M. Iacoboni; T. Schormann; K. Amunts; N. Palomero-Gallagher; S. Geyer; L. Parsons; K. Narr; N. Kabani; G. le Goualher; J. Feidler; K. Smith; D. I. Boomsma; H. H. Pol; T. Cannon; R. Kawashima; B. Mazoyer

2001-01-01

245

Morphology and distribution of dopaminergic neurons intrinsic to the human striatum.  

PubMed

The putative dopaminergic (DA) neurons intrinsic to the human striatum were studied by applying immunofluorescence and quantitative methods to postmortem tissue from seven normal individuals. Stringent morphological and chemical criteria were used to identify striatal DA neurons, including immunostaining for tyrosine hydroxylase, DA transporter and neuronal nuclear protein. The DA neurons were scattered throughout the striatum, but abounded particularly in its ventral portion. Frequency distribution of surface areas of DA cell bodies reveals that the most frequent DA neurons (x =58.0%, S.D.=12.8%) had a medium-sized (approximately 200+/-15 microm2) perikaryon with 3-5 varicose dendrites, whereas others (x =35.5%, S.D.=14.0%) had a smaller (approximately 140+/-15 microm2) perikaryon with 3-4 varicose dendrites. There was a small number (x =6.5%, S.D.=8.5%) of larger DA neurons (209-584 microm2) with spiny dendrites and a few TH-immunoreactive cells displaying mixed neuron-glia morphology. Despite significant inter-individual variations in neuron density, the human striatum (mean volume of 8.76 cm3) harbored a mean of 331.9 DA neurons (S.D.=199.2). A prolific zone, containing about 3000 cells, occurred in the ventral striatum in two brains. The addition of these cells would increase by about 10 times the total number of striatal DA neurons, which should not be confounded with segments of nigrostriatal DA fibers that displayed large (8-12 microm) varicosities and looked like small bipolar neurons. The function of striatal DA neurons is unknown but the fact that their number increases markedly following lesion of nigral DA input or administration of various growth factors, opens up new therapeutic avenues for treatment of Parkinson's disease. PMID:15589697

Cossette, Martine; Lecomte, Frédéric; Parent, André

2005-01-01

246

Cerebral organoids model human brain development and microcephaly.  

PubMed

The complexity of the human brain has made it difficult to study many brain disorders in model organisms, highlighting the need for an in vitro model of human brain development. Here we have developed a human pluripotent stem cell-derived three-dimensional organoid culture system, termed cerebral organoids, that develop various discrete, although interdependent, brain regions. These include a cerebral cortex containing progenitor populations that organize and produce mature cortical neuron subtypes. Furthermore, cerebral organoids are shown to recapitulate features of human cortical development, namely characteristic progenitor zone organization with abundant outer radial glial stem cells. Finally, we use RNA interference and patient-specific induced pluripotent stem cells to model microcephaly, a disorder that has been difficult to recapitulate in mice. We demonstrate premature neuronal differentiation in patient organoids, a defect that could help to explain the disease phenotype. Together, these data show that three-dimensional organoids can recapitulate development and disease even in this most complex human tissue. PMID:23995685

Lancaster, Madeline A; Renner, Magdalena; Martin, Carol-Anne; Wenzel, Daniel; Bicknell, Louise S; Hurles, Matthew E; Homfray, Tessa; Penninger, Josef M; Jackson, Andrew P; Knoblich, Juergen A

2013-08-28

247

Attention System of the Human Brain.  

National Technical Information Service (NTIS)

The concept of attention as central to human performance extends back to the start of experimental psychology, yet even a few years ago, it would not have been possible to outline in even a preliminary form a functional anatomy of the human attentional sy...

M. I. Posner S. E. Petersen

1989-01-01

248

Human brain functional MRI and DTI visualization with virtual reality  

PubMed Central

Magnetic resonance diffusion tensor imaging (DTI) and functional MRI (fMRI) are two active research areas in neuroimaging. DTI is sensitive to the anisotropic diffusion of water exerted by its macromolecular environment and has been shown useful in characterizing structures of ordered tissues such as the brain white matter, myocardium, and cartilage. The diffusion tensor provides two new types of information of water diffusion: the magnitude and the spatial orientation of water diffusivity inside the tissue. This information has been used for white matter fiber tracking to review physical neuronal pathways inside the brain. Functional MRI measures brain activations using the hemodynamic response. The statistically derived activation map corresponds to human brain functional activities caused by neuronal activities. The combination of these two methods provides a new way to understand human brain from the anatomical neuronal fiber connectivity to functional activities between different brain regions. In this study, virtual reality (VR) based MR DTI and fMRI visualization with high resolution anatomical image segmentation and registration, ROI definition and neuronal white matter fiber tractography visualization and fMRI activation map integration is proposed. Rationale and methods for producing and distributing stereoscopic videos are also discussed.

Chen, Bin; Moreland, John; Zhang, Jingyu

2011-01-01

249

Abnormal brain iron homeostasis in human and animal prion disorders.  

PubMed

Neurotoxicity in all prion disorders is believed to result from the accumulation of PrP-scrapie (PrP(Sc)), a beta-sheet rich isoform of a normal cell-surface glycoprotein, the prion protein (PrP(C)). Limited reports suggest imbalance of brain iron homeostasis as a significant associated cause of neurotoxicity in prion-infected cell and mouse models. However, systematic studies on the generality of this phenomenon and the underlying mechanism(s) leading to iron dyshomeostasis in diseased brains are lacking. In this report, we demonstrate that prion disease-affected human, hamster, and mouse brains show increased total and redox-active Fe (II) iron, and a paradoxical increase in major iron uptake proteins transferrin (Tf) and transferrin receptor (TfR) at the end stage of disease. Furthermore, examination of scrapie-inoculated hamster brains at different timepoints following infection shows increased levels of Tf with time, suggesting increasing iron deficiency with disease progression. Sporadic Creutzfeldt-Jakob disease (sCJD)-affected human brains show a similar increase in total iron and a direct correlation between PrP and Tf levels, implicating PrP(Sc) as the underlying cause of iron deficiency. Increased binding of Tf to the cerebellar Purkinje cell neurons of sCJD brains further indicates upregulation of TfR and a phenotype of neuronal iron deficiency in diseased brains despite increased iron levels. The likely cause of this phenotype is sequestration of iron in brain ferritin that becomes detergent-insoluble in PrP(Sc)-infected cell lines and sCJD brain homogenates. These results suggest that sequestration of iron in PrP(Sc)-ferritin complexes induces a state of iron bio-insufficiency in prion disease-affected brains, resulting in increased uptake and a state of iron dyshomeostasis. An additional unexpected observation is the resistance of Tf to digestion by proteinase-K, providing a reliable marker for iron levels in postmortem human brains. These data implicate redox-iron in prion disease-associated neurotoxicity, a novel observation with significant implications for prion disease pathogenesis. PMID:19283067

Singh, Ajay; Isaac, Alfred Orina; Luo, Xiu; Mohan, Maradumane L; Cohen, Mark L; Chen, Fusong; Kong, Qingzhong; Bartz, Jason; Singh, Neena

2009-03-13

250

Arterial territories of the human brain.  

PubMed

We present a brain map of the areas supplied by various arteries in the brainstem, cerebellum and cerebral hemispheres. Arterial territories are depicted in a form that is directly applicable to neuroimaging slices in clinical practice. The arterial territories are outlined based on an extensive overview of anatomical studies of cerebral blood supply. For arterial territories of the hemispheres, we present the variability of the cortical territories of the three main cerebral arteries and define the minimal and maximal cortical supply areas. PMID:22377874

Tatu, Laurent; Moulin, Thierry; Vuillier, Fabrice; Bogousslavsky, Julien

2012-02-14

251

A comparative morphological study of human germ cells in vitro or in situ within seminiferous tubules.  

PubMed

For many infertile couples, intracytoplasmic germ cell/spermatozoon injection into unfertilized eggs may be their only hope for producing their own biological children. Thus far, success with injection of pre-spermatozoan germ cells such as round spermatids has not been as great as that of spermatozoon injection. This could be due in part to the difficulty of identifying younger (less mature) male germ cells in testicular biopsy dispersions. To improve the identification of various types of live, dispersed, human testicular cells in vitro, a comparative study of the morphological characteristics of human spermatogenic germ cells in vitro or in situ within seminiferous tubules was conducted. Live human testicular tissue was obtained from an organ-donating, brain-dead person with a high density of various germ cells. A cell suspension was obtained by enzymatic digestion, and cells were cultured for 3 days in an excessive volume (100-fold medium:cells; v:v) of HEPES-TC 199 medium at 5 degrees C and observed live with Nomarski optics (interference-contrast microscopy). For comparative purposes, testes from ten men obtained at autopsy were fixed, embedded in epoxy resin, sectioned at 20 microm, and observed unstained by Nomarski optics. This approach allowed comparison of morphological characteristics of individual germ cells seen in vitro or in situ in the human testis. In both live and fixed preparations from control men with varied daily sperm production rates, Sertoli cells have oval to pear-shaped nuclei with indented nuclear envelopes and large nucleoli, which makes their appearance distinctly different from germ cells. The size, shape, and chromatin pattern of nuclei, and the presence of meiotic metaphase figures, acrosomic vesicles/structures, tails, and/or mitochondria in the middle piece of germ cells are characteristically seen in live cells in vitro and in those cells observed in the fixed seminiferous tubules. Hence, this comparative approach allows verification of the identity of individual germ cells seen in vitro and provides a checklist of distinguishing characteristics of live human germ cells, to be used by scientists and technical staff in infertility clinics when selecting specific germ cells from a testicular aspirate or enzymatically digested biopsy. PMID:10491626

Johnson, L; Neaves, W B; Barnard, J J; Keillor, G E; Brown, S W; Yanagimachi, R

1999-10-01

252

Morphology and Evolutionary Biology of the Dolphin (Delphinus sp.) Brain – MR Imaging and Conventional Histology  

Microsoft Academic Search

Whole brains of the common dolphin (Delphinus delphis) were studied using magnetic resonance imaging (MRI) in parallel with conventional histology. One formalin-fixed brain was documented with a Siemens Trio Magnetic Resonance scanner and compared to three other brains which were embedded in celloidin, sectioned in the three main planes and stained for cells and fibers. The brain of the common

H. H. A. Oelschläger; M. Haas-Rioth; C. Fung; S. H. Ridgway; M. Knauth

2008-01-01

253

Uncovering Intrinsic Modular Organization of Spontaneous Brain Activity in Humans  

PubMed Central

The characterization of topological architecture of complex brain networks is one of the most challenging issues in neuroscience. Slow (<0.1 Hz), spontaneous fluctuations of the blood oxygen level dependent (BOLD) signal in functional magnetic resonance imaging are thought to be potentially important for the reflection of spontaneous neuronal activity. Many studies have shown that these fluctuations are highly coherent within anatomically or functionally linked areas of the brain. However, the underlying topological mechanisms responsible for these coherent intrinsic or spontaneous fluctuations are still poorly understood. Here, we apply modern network analysis techniques to investigate how spontaneous neuronal activities in the human brain derived from the resting-state BOLD signals are topologically organized at both the temporal and spatial scales. We first show that the spontaneous brain functional networks have an intrinsically cohesive modular structure in which the connections between regions are much denser within modules than between them. These identified modules are found to be closely associated with several well known functionally interconnected subsystems such as the somatosensory/motor, auditory, attention, visual, subcortical, and the “default” system. Specifically, we demonstrate that the module-specific topological features can not be captured by means of computing the corresponding global network parameters, suggesting a unique organization within each module. Finally, we identify several pivotal network connectors and paths (predominantly associated with the association and limbic/paralimbic cortex regions) that are vital for the global coordination of information flow over the whole network, and we find that their lesions (deletions) critically affect the stability and robustness of the brain functional system. Together, our results demonstrate the highly organized modular architecture and associated topological properties in the temporal and spatial brain functional networks of the human brain that underlie spontaneous neuronal dynamics, which provides important implications for our understanding of how intrinsically coherent spontaneous brain activity has evolved into an optimal neuronal architecture to support global computation and information integration in the absence of specific stimuli or behaviors.

He, Yong; Wang, Jinhui; Wang, Liang; Chen, Zhang J.; Yan, Chaogan; Yang, Hong; Tang, Hehan; Zhu, Chaozhe; Gong, Qiyong; Zang, Yufeng; Evans, Alan C.

2009-01-01

254

Uncovering intrinsic modular organization of spontaneous brain activity in humans.  

PubMed

The characterization of topological architecture of complex brain networks is one of the most challenging issues in neuroscience. Slow (<0.1 Hz), spontaneous fluctuations of the blood oxygen level dependent (BOLD) signal in functional magnetic resonance imaging are thought to be potentially important for the reflection of spontaneous neuronal activity. Many studies have shown that these fluctuations are highly coherent within anatomically or functionally linked areas of the brain. However, the underlying topological mechanisms responsible for these coherent intrinsic or spontaneous fluctuations are still poorly understood. Here, we apply modern network analysis techniques to investigate how spontaneous neuronal activities in the human brain derived from the resting-state BOLD signals are topologically organized at both the temporal and spatial scales. We first show that the spontaneous brain functional networks have an intrinsically cohesive modular structure in which the connections between regions are much denser within modules than between them. These identified modules are found to be closely associated with several well known functionally interconnected subsystems such as the somatosensory/motor, auditory, attention, visual, subcortical, and the "default" system. Specifically, we demonstrate that the module-specific topological features can not be captured by means of computing the corresponding global network parameters, suggesting a unique organization within each module. Finally, we identify several pivotal network connectors and paths (predominantly associated with the association and limbic/paralimbic cortex regions) that are vital for the global coordination of information flow over the whole network, and we find that their lesions (deletions) critically affect the stability and robustness of the brain functional system. Together, our results demonstrate the highly organized modular architecture and associated topological properties in the temporal and spatial brain functional networks of the human brain that underlie spontaneous neuronal dynamics, which provides important implications for our understanding of how intrinsically coherent spontaneous brain activity has evolved into an optimal neuronal architecture to support global computation and information integration in the absence of specific stimuli or behaviors. PMID:19381298

He, Yong; Wang, Jinhui; Wang, Liang; Chen, Zhang J; Yan, Chaogan; Yang, Hong; Tang, Hehan; Zhu, Chaozhe; Gong, Qiyong; Zang, Yufeng; Evans, Alan C

2009-04-21

255

Simple instrument for biochemical studies of the living human brain  

SciTech Connect

A simple, relatively inexpensive radiation detection system was developed for measurement of positron-emitting receptor-binding drugs in the human brain. This high-efficiency coincidence counting system requires that only a few hundred microcuries of labeled drug be administered to the subject, thereby allowing for multiple studies without an excessive radiation dose. Measurement of the binding of (/sup 11/C)-carfentanil, a high-affinity synthetic opiate, to opiate receptors in the presence and in the absence of a competitive opiate antagonist exemplifies the use of this system for estimating different degrees of receptor binding of drugs in the human brain. The instrument has also been used for measurement of the transport into the brain of other positron-emitting radiotracers, such as large neutral amino acids.

Bice, A.N.; Wagner, H.N. Jr.; Lee, M.C.; Frost, J.J.

1986-09-01

256

Hexokinase 'binding sites' of normal and tumoral human brain mitochondria.  

PubMed

Interaction of type I hexokinase (HK-I) with the mitochondria obtained from the biopsy specimens of normal and tumoral human brain tissues was studied in the present investigation. This effort was undertaken with the aim of exploring possible differences in the mode of association of the enzyme with the outer mitochondrial membrane in the described sources. Results indicate that the two 'sites' for binding of HK-I suggested in the literature, based on extensive studies carried out on rat brain mitochondria, are similarly present in the human brain mitochondria. Differences in the microenvironments of HK binding, as reflected by the presented data, are suggested to be of importance in regulation of the catalytic potential of the bound enzyme. The real metabolic significance of this association in relation to cancer and its practical importance would need further investigation. PMID:11204446

Golestani, A; Nemat-Gorgani, M

2000-12-01

257

Accelerated Evolution of the ASPM Gene Controlling Brain Size Begins Prior to Human Brain Expansion  

Microsoft Academic Search

Primary microcephaly (MCPH) is a neurodevelopmental disorder characterized by global reduction in cerebral cortical volume. The microcephalic brain has a volume comparable to that of early hominids, raising the possibility that some MCPH genes may have been evolutionary targets in the expansion of the cerebral cortex in mammals and especially primates. Mutations in ASPM, which encodes the human homologue of

Natalay Kouprina; Adam Pavlicek; Ganeshwaran H. Mochida; Gregory Solomon; William Gersch; Young-Ho Yoon; Randall Collura; Maryellen Ruvolo; J. Carl Barrett; C. Geoffrey Woods; Christopher A. Walsh; Jerzy Jurka; Vladimir Larionov

2004-01-01

258

Monoclonal antibodies to human brain acetylcholinesterase: properties and applications  

Microsoft Academic Search

1.Acetylcholinesterase (AChE) was purified 20,000-fold in a 43% yield from 90 g of human cerebellum by combined immunoaffinity and ligand affinity chromatography. The purified enzyme migrated as a 68,000-dalton band during polyacrylamide gel electrophoresis under denaturing and reducing conditions.2.Balb\\/c mice were immunized with multiple 10-µg injections of this material in order to raise monoclonal antibodies to human brain AChE. Three

Zoltan Rakonczay; Stephen Brimijoin

1988-01-01

259

Abstract representations of numbers in the animal and human brain  

Microsoft Academic Search

There is evidence to suggest that animals, young infants and adult humans possess a biologically determined, domain-specific representation of number and of elementary arithmetic operations. Behavioral studies in infants and animals reveal number perception, discrimination and elementary calculation abilities in non-verbal organisms. Lesion and brain-imaging studies in humans indicate that a specific neural substrate, located in the left and right

Stanislas Dehaene; Ghislaine Dehaene-Lambertz; Laurent Cohen

1998-01-01

260

Culture of Glial Cells from Human Brain Biopsies  

Microsoft Academic Search

\\u000a Surgical resections of selected human brain areas, to ameliorate intractable epilepsy, provide opportunities to isolate, maintain,\\u000a and examine nonmalignant human neural cells in vitro. Because these specimens tend to be from patients of early adulthood\\u000a or older, neurons do not survive the isolation process; the cells extracted are thus of glial origin, and include oligodendrocytes,\\u000a astrocytes, and microglial cells. In

V. Wee Yong; Jack P. Antel

261

Widespread splicing changes in human brain development and aging  

PubMed Central

While splicing differences between tissues, sexes and species are well documented, little is known about the extent and the nature of splicing changes that take place during human or mammalian development and aging. Here, using high-throughput transcriptome sequencing, we have characterized splicing changes that take place during whole human lifespan in two brain regions: prefrontal cortex and cerebellum. Identified changes were confirmed using independent human and rhesus macaque RNA-seq data sets, exon arrays and PCR, and were detected at the protein level using mass spectrometry. Splicing changes across lifespan were abundant in both of the brain regions studied, affecting more than a third of the genes expressed in the human brain. Approximately 15% of these changes differed between the two brain regions. Across lifespan, splicing changes followed discrete patterns that could be linked to neural functions, and associated with the expression profiles of the corresponding splicing factors. More than 60% of all splicing changes represented a single splicing pattern reflecting preferential inclusion of gene segments potentially targeting transcripts for nonsense-mediated decay in infants and elderly.

Mazin, Pavel; Xiong, Jieyi; Liu, Xiling; Yan, Zheng; Zhang, Xiaoyu; Li, Mingshuang; He, Liu; Somel, Mehmet; Yuan, Yuan; Phoebe Chen, Yi-Ping; Li, Na; Hu, Yuhui; Fu, Ning; Ning, Zhibin; Zeng, Rong; Yang, Hongyi; Chen, Wei; Gelfand, Mikhail; Khaitovich, Philipp

2013-01-01

262

Neural encoding of movement sequences in the human brain.  

PubMed

Humans learn and remember thousands of motor skills, but how these skills are represented in the brain is not well understood. A recent study by Wiestler and Diedrichsen demonstrates for the first time that individual motor sequences can be identified based on the pattern of neural activity in a distributed network of motor cortical regions. PMID:23973185

Penhune, Virginia B

2013-08-21

263

Language production: electroencephalographic localization in the normal human brain.  

PubMed

Slow negative potentials, which are at a maximum over Broca's area in the left hemisphere, were recorded when normnal subjects spontaneously produced polysyllabic words. Bilaterally symmetrical potentials were seen with analogous, nonspeech control gestures. These potentials began up to 1 second before word or gesture articulation. These results are the first demonstration of localization of language production in normal human brain. PMID:5550508

McAdam, D W; Whitaker, H A

1971-04-30

264

Right-lateralized Brain Oscillations in Human Spatial Navigation  

Microsoft Academic Search

During spatial navigation, lesion and functional imaging studies suggest that the right hemisphere has a unique functional role. However, studies of direct human brain recordings have not reported interhemisphere differences in navigationrelated oscillatory activity. We investigated this apparent discrepancy using intracranial electroencephalographic recordings from 24 neurosurgical patients playing a virtual taxi driver game. When patients were virtually moving in the

Joshua Jacobs; Joseph R. Madsen; Michael J. Kahana

2009-01-01

265

Right-lateralized Brain Oscillations in Human Spatial Navigation  

Microsoft Academic Search

During spatial navigation, lesion and functional imaging studies suggest that the right hemisphere has a unique func- tional role. However, studies of direct human brain recordings have not reported interhemisphere differences in navigation- related oscillatory activity. We investigated this apparent dis- crepancy using intracranial electroencephalographic recordings from 24 neurosurgical patients playing a virtual taxi driver game. When patients were virtually

Joshua Jacobs; Igor O. Korolev; Jeremy B. Caplan; Arne D. Ekstrom; Brian Litt; Gordon Baltuch; Itzhak Fried; Andreas Schulze-Bonhage; Joseph R. Madsen; Michael J. Kahana

2010-01-01

266

Exposure to appetitive food stimuli markedly activates the human brain  

Microsoft Academic Search

Objective: The increased incidence of obesity most likely reflects changes in the environment that had made food more available and palatable. Here we assess the response of the human brain to the presentation of appetitive food stimuli during food presentation using PET and FDG. Method: Metabolic changes in response to food presentation were done in 12 healthy normal body weight

Gene-Jack Wang; Nora D Volkow; Frank Telang; Millard Jayne; Jim Ma; Manlong Rao; Wei Zhu; Christopher T Wong; Naomi R Pappas; Allan Geliebter; Joanna S Fowler

2004-01-01

267

Quantitative MRI measurements of human fetal brain development in utero  

Microsoft Academic Search

Magnetic resonance imaging (MRI) allows for high resolution imaging of the central nervous system. We have tested the feasibility of using MRI in conjunction with quantitative image analysis to perform volumetric measurements of the brain in the developing human fetus in utero. The database comprises MR images of a total of 56 fetuses (gestational age 25–41 weeks) referred because of suspected

Rachel Grossman; Chen Hoffman; Yael Mardor; Anat Biegon

2006-01-01

268

Using Your Brain for Human-Computer Interaction  

Microsoft Academic Search

To further increase the bandwidth from humans to comput- ers, I am investigating methods for sensing signals that users naturally give off while using a computer system. I plan to use this data to augment the explicit input that the user provides through standard input devices. Using a rela- tively new brain imaging tool called functional near- infrared spectroscopy, along

Erin Treacy Solovey

2009-01-01

269

The power of love on the human brain  

Microsoft Academic Search

Romantic love has been the source for some of the greatest achievements of mankind throughout the ages. The recent localization of romantic love within subcortico–cortical reward, motivation and emotion systems in the human brain has suggested that love is a goal-directed drive with predictable facilitation effects on cognitive behavior, rather than a pure emotion. Here we show that the subliminal

Francesco Bianchi-Demicheli; Scott T. Grafton; Stephanie Ortigue

2006-01-01

270

Beyond FearEmotional Memory Mechanisms in the Human Brain  

Microsoft Academic Search

Neurobiological accounts of emotional memory have been derived largely from animal models investigating the encoding and retention of memories for events that signal threat. This literature has implicated the amygdala, a structure in the brain's temporal lobe, in the learning and consolidation of fear memories. Its role in fear conditioning has been confirmed, but the human amygdala also interacts with

Kevin S. LaBar

2007-01-01

271

Functional magnetic resonance imaging (FMRI) of the human brain  

Microsoft Academic Search

Functional magnetic resonance imaging (FMRI) can provide detailed images of human brain that reflect localized changes in cerebral blood flow and oxygenation induced by sensory, motor, or cognitive tasks. This review presents methods for gradient-recalled echo-planar functional magnetic resonance imaging (FMRI). Also included is a discussion of the hypothesized basis of FMRI, imaging hardware, a unique visual stimulation apparatus, image

Edgar A. DeYoe; Peter Bandettini; Jay Neitz; David Miller; Paula Winans

1994-01-01

272

Apoptosis in human primary brain tumours: actions of arachidonic acid  

Microsoft Academic Search

It has been postulated that loss of proliferative control in tumour cells is a consequence of depletion of cellular arachidonic acid (AA) and that exogenous AA and n-6 fatty acids may restore control of proliferation. To test this hypothesis and to investigate the activity of AA, apoptosis in human primary brain tumour cells was analysed using flow terminal deoxynucleotide transferase

J. R. Williams; H. A. Leaver; J. W. Ironside; E. P. Miller; I. R. Whittle; A. Gregor

1998-01-01

273

Integration of Letters and Speech Sounds in the Human Brain  

Microsoft Academic Search

Most people acquire literacy skills with remarkable ease, even though the human brain is not evolutionarily adapted to this relatively new cultural phenomenon. Associations between letters and speech sounds form the basis of reading in alphabetic scripts. We investigated the functional neuroanatomy of the integration of letters and speech sounds using functional magnetic resonance imaging (fMRI). Letters and speech sounds

Nienke van Atteveldt; Elia Formisano; Rainer Goebel; Leo Blomert

2004-01-01

274

Prefrontal cognitive systems in schizophrenia : Towards human genetic brain mechanisms  

Microsoft Academic Search

Schizophrenia has complex genetic heritability. It is also genetically heterogeneous. To the extent that genes are associated with symptom constellations in schizophrenia, they do so by affecting the development and function of neural systems that mediate the expression of such diverse behavioral, cognitive and perceptual phenomena. The genetic mechanisms of human brain dysfunction remain to be well understood. “Imaging genetics”

Hao-Yang Tan; Joseph H. Callicott; Daniel R. Weinberger

2009-01-01

275

Invariant visual representation by single neurons in the human brain  

Microsoft Academic Search

It takes a fraction of a second to recognize a person or an object even when seen under strikingly different conditions. How such a robust, high-level representation is achieved by neurons in the human brain is still unclear. In monkeys, neurons in the upper stages of the ventral visual pathway respond to complex images such as faces and objects and

R. Quian Quiroga; L. Reddy; G. Kreiman; C. Koch; I. Fried

2005-01-01

276

Optical properties of native and coagulated human brain structures  

Microsoft Academic Search

The laser-induced interstitial thermo-therapy of brain tumors requires an exact therapy planning. Therefore, the knowledge of the optical properties of native (na) and coagulated (co) tissue structures is important. In this study the optical properties of native and thermally coagulated (2 h, 80 degree Celsius) human white (n equals 14; na equals 7, co equals 7) and gray matter (n

Hans-Joachim Schwarzmaier; Anna N. Yaroslavsky; Ilya V. Yaroslavsky; Thomas Goldbach; Thomas Kahn; Frank Ulrich; Paul C. Schulze; Ralf Schober

1997-01-01

277

A mouse model of human repetitive mild traumatic brain injury  

Microsoft Academic Search

A novel method for the study of repetitive mild traumatic brain injury (rmTBI) that models the most common form of head injury in humans is presented. Existing animal models of TBI impart focal, severe damage unlike that seen in repeated and mild concussive injuries, and few are configured for repetitive application. Our model is a modification of the Marmarou weight

Michael J. Kane; Mariana Angoa-Pérez; Denise I. Briggs; David C. Viano; Christian W. Kreipke; Donald M. Kuhn

278

Morphofunctional Study of the Therapeutic Efficacy of Human Mesenchymal and Neural Stem Cells in Rats with Diffuse Brain Injury  

Microsoft Academic Search

We studied the effect of transplantation of human stem cells from various tissues on reparative processes in the brain of\\u000a rats with closed craniocerebral injury. Combined treatment with standard drugs and systemic administration of xenogeneic stem\\u000a cells had a neuroprotective effect. The morphology of neurons rapidly returned to normal after administration of fetal neural\\u000a stem cells. Fetal mesenchymal stem cells

A. F. Tsyb; V. V. Yuzhakov; L. M. Roshal’; G. T. Sukhikh; A. G. Konoplyannikov; G. N. Sushkevich; N. D. Yakovleva; I. E. Ingel’; L. N. Bandurko; L. E. Sevan’kaeva; L. N. Mikhina; N. K. Fomina; M. V. Marei; Zh. B. Semenova; O. A. Konoplyannikova; S. Sh. Kal’sina; L. A. Lepekhina; I. V. Semenkova; E. V. Agaeva; A. S. Shevchuk; L. N. Pavlova; O. Yu. Tokarev; O. V. Karaseva; T. A. Chernyshova

2009-01-01

279

Neuronal apoptosis following human brain injury.  

PubMed

Neuronal apoptosis has been investigated in paraffin-embedded brain tissue from 103 individuals who had sustained blunt head injury by use of the in situ nick translation (ISNT) technique. In order to provide reliable data for a forensic wound age estimation, a quantitative morphometric analysis was performed. Apoptotic neuronal cells could be detected in a cortical contusion with a wound age of 45 min at the earliest and in the majority of the cases with postinfliction intervals up to 2 weeks, numerous ISNT-positive cells were found adjacent to the traumatically injured area. The presented data indicate that neuronal apoptosis peaks at about 1 day and persists for at least 22 weeks after blunt head injury. The time-dependent occurrence of apoptotic cells can contribute to a forensic timing of cortical contusions and complements other immunohistochemical parameters, especially in the early postinfliction interval. PMID:14625778

Hausmann, R; Biermann, T; Wiest, I; Tübel, J; Betz, P

2003-11-18

280

Mathematical logic in the human brain: syntax.  

PubMed

Theory predicts a close structural relation of formal languages with natural languages. Both share the aspect of an underlying grammar which either generates (hierarchically) structured expressions or allows us to decide whether a sentence is syntactically correct or not. The advantage of rule-based communication is commonly believed to be its efficiency and effectiveness. A particularly important class of formal languages are those underlying the mathematical syntax. Here we provide brain-imaging evidence that the syntactic processing of abstract mathematical formulae, written in a first order language, is, indeed efficient and effective as a rule-based generation and decision process. However, it is remarkable, that the neural network involved, consisting of intraparietal and prefrontal regions, only involves Broca's area in a surprisingly selective way. This seems to imply that despite structural analogies of common and current formal languages, at the neural level, mathematics and natural language are processed differently, in principal. PMID:19478999

Friedrich, Roland; Friederici, Angela D

2009-05-28

281

Addiction Circuitry in the Human Brain*  

PubMed Central

A major challenge in understanding substance-use disorders lies in uncovering why some individuals become addicted when exposed to drugs, whereas others do not. Although genetic, developmental, and environmental factors are recognized as major contributors to a person’s risk of becoming addicted, the neurobiological processes that underlie this vulnerability are still poorly understood. Imaging studies suggest that individual variations in key dopamine-modulated brain circuits, including circuits involved in reward, memory, executive function, and motivation, contribute to some of the differences in addiction vulnerability. A better understanding of the main circuits affected by chronic drug use and the influence of social stressors, developmental trajectories, and genetic background on these circuits is bound to lead to a better understanding of addiction and to more effective strategies for the prevention and treatment of substance-use disorders.

Volkow, Nora D.; Wang, Gene-Jack; Fowler, Joanna S.; Tomasi, Dardo

2012-01-01

282

Mathematical Logic in the Human Brain: Syntax  

PubMed Central

Theory predicts a close structural relation of formal languages with natural languages. Both share the aspect of an underlying grammar which either generates (hierarchically) structured expressions or allows us to decide whether a sentence is syntactically correct or not. The advantage of rule-based communication is commonly believed to be its efficiency and effectiveness. A particularly important class of formal languages are those underlying the mathematical syntax. Here we provide brain-imaging evidence that the syntactic processing of abstract mathematical formulae, written in a first order language, is, indeed efficient and effective as a rule-based generation and decision process. However, it is remarkable, that the neural network involved, consisting of intraparietal and prefrontal regions, only involves Broca's area in a surprisingly selective way. This seems to imply that despite structural analogies of common and current formal languages, at the neural level, mathematics and natural language are processed differently, in principal.

Friedrich, Roland; Friederici, Angela D.

2009-01-01

283

Rock magnetism linked to human brain magnetite  

NASA Astrophysics Data System (ADS)

Magnetite has a long and distinguished career as one of the most important minerals in geophysics, as it is responsible for most of the remanent magnetization in marine sediments and the oceanic crust. It may come as a surprise to discover that it also ranks as the third or fourth most diverse mineral product formed biochemically by living organisms, and forms naturally in a variety of human tissues [Kirschvink et al., 1992].Magnetite was discovered in teeth of the Polyplacophora mollusks over 30 years ago, in magnetotactic bacteria nearly 20 years ago, in honey bees and homing pigeons nearly 15 years ago, but only recently in human tissue.

Kirschvink, Joseph L.

284

Early morphologic and spectroscopic magnetic resonance in severe traumatic brain injuries can detect "invisible brain stem damage" and predict "vegetative states".  

PubMed

A precise evaluation of the brain damage in the first days of severe traumatic brain injured (TBI) patients is still uncertain despite numerous available cerebral evaluation methods and imaging. In 5-10% of severe TBI patients, clinicians remain concerned with prolonged coma and long-term marked cognitive impairment unexplained by normal morphological T2 star, flair, and diffusion magnetic resonance imaging (MRI). For this reason, we prospectively assessed the potential value of magnetic resonance spectroscopy (MRS) of the brain stem to evaluate the functionality of the consciousness areas. Forty consecutive patients with severe TBI were included. Single voxel proton MRS of the brain stem and morphological MRI of the whole brain were performed at day 17.5 +/- 6.4. Disability Rating Scale and Glasgow Outcome Scale (GOS) were evaluated at 18 months posttrauma. MRS appeared to be a reliable tool in the exploration of brainstem metabolism in TBI. Three different spectra were observed (normal, cholinergic reaction, or neuronal damage) allowing an evaluation of functional damage. MRS disturbances were not correlated with anatomical MRI lesions suggesting that the two techniques are strongly complementarity. In two GOS 2 vegetative patients with normal morphological MRI, MRS detected severe functional damage of the brainstem (NAA/Cr < 1.50) that was described as "invisible brain stem damage." MRI and MRS taken separately could not distinguish patients GOS 3 (n = 7) from GOS 1-2 (n = 11) and GOS 4-5 (n = 20). However, a principal component analysis of combined MRI and MRS data enabled a clear-cut separation between GOS 1-2, GOS 3, and GOS 4-5 patients with no overlap between groups. This study showed that combined MRI and MRS provide a reliable evaluation of patients presenting in deep coma, specially when there are insufficient MRI lesions of the consciousness pathways to explain their status. In the first few days post-trauma metabolic (brainstem spectroscopy) and morphological (T2 star and Flair) MRI studies can predict the long-term neurological outcome, especially the persistent vegetative states and minimally conscious state. PMID:16689669

Carpentier, Alexandre; Galanaud, Damien; Puybasset, Louis; Muller, Jean-Charles; Lescot, Thomas; Boch, Anne-Laure; Riedl, Valentin; Riedl, Vincent; Cornu, Philippe; Coriat, Pierre; Dormont, Didier; van Effenterre, Remy

2006-05-01

285

Development of a Human Brain Diffusion Tensor Template  

PubMed Central

The development of a brain template for diffusion tensor imaging (DTI) is crucial for comparisons of neuronal structural integrity and brain connectivity across populations, as well as for the development of a white matter atlas. Previous efforts to produce a DTI brain template have been compromised by factors related to image quality, the effectiveness of the image registration approach, the appropriateness of subject inclusion criteria, the completeness and accuracy of the information summarized in the final template. The purpose of this work was to develop a DTI human brain template using techniques that address the shortcomings of previous efforts. Therefore, data containing minimal artifacts were first obtained on 67 healthy human subjects selected from an age-group with relatively similar diffusion characteristics (20–40 years of age), using an appropriate DTI acquisition protocol. Non-linear image registration based on mean diffusion-weighted and fractional anisotropy images was employed. DTI brain templates containing median and mean tensors were produced in ICBM-152 space and made publicly available. The resulting set of DTI templates is characterized by higher image sharpness, provides the ability to distinguish smaller white matter fiber structures, contains fewer image artifacts, than previously developed templates, and to our knowledge, is one of only two templates produced based on a relatively large number of subjects. Furthermore, median tensors were shown to better preserve the diffusion characteristics at the group level than mean tensors. Finally, white matter fiber tractography was applied on the template and several fiber-bundles were traced.

Peng, Huiling; Orlichenko, Anton; Dawe, Robert J.; Agam, Gady; Zhang, Shengwei; Arfanakis, Konstantinos

2009-01-01

286

Visualization of specific binding sites of benzodiazepine in human brain  

SciTech Connect

Using 11C-labeled Ro15-1788 and positron emission tomography, studies of benzodiazepine binding sites in the human brain were performed on four normal volunteers. Rapid and high accumulation of 11C activity was observed in the brain after i.v. injection of (11C)Ro15-1788, the maximum of which was within 12 min. Initial distribution of 11C activity in the brain was similar to the distribution of the normal cerebral blood flow. Ten minutes after injection, however, a high uptake of 11C activity was observed in the cerebral cortex and moderate uptake was seen in the cerebellar cortex, the basal ganglia, and the thalamus. The accumulation of 11C activity was low in the brain stem. This distribution of 11C activity was approximately parallel to the known distribution of benzodiazepine receptors. Saturation experiments were performed on four volunteers with oral administration of 0.3-1.8 mg/kg of cold Ro15-1788 prior to injection. Initial distribution of 11C activity following injection peaked within 2 min and then the accumulation of 11C activity decreased rapidly and remarkably throughout the brain. The results indicated that (11C) Ro15-1788 associates and dissociates to specific and nonspecific binding sites rapidly and has a high ratio of specific receptor binding to nonspecific binding in vivo. Carbon-11 Ro15-1788 is a suitable radioligand for the study of benzodiazepine receptors in vivo in humans.

Shinotoh, H.; Yamasaki, T.; Inoue, O.; Itoh, T.; Suzuki, K.; Hashimoto, K.; Tateno, Y.; Ikehira, H.

1986-10-01

287

Modeling the impact of lesions in the human brain.  

PubMed

Lesions of anatomical brain networks result in functional disturbances of brain systems and behavior which depend sensitively, often unpredictably, on the lesion site. The availability of whole-brain maps of structural connections within the human cerebrum and our increased understanding of the physiology and large-scale dynamics of cortical networks allow us to investigate the functional consequences of focal brain lesions in a computational model. We simulate the dynamic effects of lesions placed in different regions of the cerebral cortex by recording changes in the pattern of endogenous ("resting-state") neural activity. We find that lesions produce specific patterns of altered functional connectivity among distant regions of cortex, often affecting both cortical hemispheres. The magnitude of these dynamic effects depends on the lesion location and is partly predicted by structural network properties of the lesion site. In the model, lesions along the cortical midline and in the vicinity of the temporo-parietal junction result in large and widely distributed changes in functional connectivity, while lesions of primary sensory or motor regions remain more localized. The model suggests that dynamic lesion effects can be predicted on the basis of specific network measures of structural brain networks and that these effects may be related to known behavioral and cognitive consequences of brain lesions. PMID:19521503

Alstott, Jeffrey; Breakspear, Michael; Hagmann, Patric; Cammoun, Leila; Sporns, Olaf

2009-06-12

288

Topological Isomorphisms of Human Brain and Financial Market Networks  

PubMed Central

Although metaphorical and conceptual connections between the human brain and the financial markets have often been drawn, rigorous physical or mathematical underpinnings of this analogy remain largely unexplored. Here, we apply a statistical and graph theoretic approach to the study of two datasets – the time series of 90 stocks from the New York stock exchange over a 3-year period, and the fMRI-derived time series acquired from 90 brain regions over the course of a 10-min-long functional MRI scan of resting brain function in healthy volunteers. Despite the many obvious substantive differences between these two datasets, graphical analysis demonstrated striking commonalities in terms of global network topological properties. Both the human brain and the market networks were non-random, small-world, modular, hierarchical systems with fat-tailed degree distributions indicating the presence of highly connected hubs. These properties could not be trivially explained by the univariate time series statistics of stock price returns. This degree of topological isomorphism suggests that brains and markets can be regarded broadly as members of the same family of networks. The two systems, however, were not topologically identical. The financial market was more efficient and more modular – more highly optimized for information processing – than the brain networks; but also less robust to systemic disintegration as a result of hub deletion. We conclude that the conceptual connections between brains and markets are not merely metaphorical; rather these two information processing systems can be rigorously compared in the same mathematical language and turn out often to share important topological properties in common to some degree. There will be interesting scientific arbitrage opportunities in further work at the graph-theoretically mediated interface between systems neuroscience and the statistical physics of financial markets.

Vertes, Petra E.; Nicol, Ruth M.; Chapman, Sandra C.; Watkins, Nicholas W.; Robertson, Duncan A.; Bullmore, Edward T.

2011-01-01

289

Induction of p-glycoprotein by antiretroviral drugs in human brain microvessel endothelial cells.  

PubMed

The membrane-associated drug transporter P-glycoprotein (P-gp) plays an essential role in drug efflux from the brain. Induction of this protein at the blood-brain barrier (BBB) could further affect the ability of a drug to enter the brain. At present, P-gp induction mediated by antiretroviral drugs at the BBB has not been fully investigated. Since P-gp expression is regulated by ligand-activated nuclear receptors, i.e., human pregnane X receptor (hPXR) and human constitutive androstane receptor (hCAR), these receptors could represent potential pathways involved in P-gp induction by antiretroviral drugs. The aims of this study were (i) to determine whether antiretroviral drugs currently used in HIV pharmacotherapy are ligands for hPXR or hCAR and (ii) to examine P-gp function and expression in human brain microvessel endothelial cells treated with antiretroviral drugs identified as ligands of hPXR and/or hCAR. Luciferase reporter gene assays were performed to examine the activation of hPXR and hCAR by antiretroviral drugs. The hCMEC/D3 cell line, which is known to display several morphological and biochemical properties of the BBB in humans, was used to examine P-gp induction following 72 h of exposure to these agents. Amprenavir, atazanavir, darunavir, efavirenz, ritonavir, and lopinavir were found to activate hPXR, whereas abacavir, efavirenz, and nevirapine were found to activate hCAR. P-gp expression and function were significantly induced in hCMEC/D3 cells treated with these drugs at clinical concentrations in plasma. Together, our data suggest that P-gp induction could occur at the BBB during chronic treatment with antiretroviral drugs identified as ligands of hPXR and/or hCAR. PMID:23836171

Chan, Gary N Y; Patel, Rucha; Cummins, Carolyn L; Bendayan, Reina

2013-07-08

290

Telomerase activity in human brain tumors: astrocytoma and meningioma.  

PubMed

Somatic cells do not have telomerase activity but immortalized cell lines and more than 85 % of the cancer cells show telomerase activation to prevent the telomere from progressive shortening. The activation of this enzyme has been found in a variety of human tumors and tumor-derived cell lines, but only few studies on telomerase activity in human brain tumors have been reported. Here, we evaluated telomerase activity in different grades of human astrocytoma and meningioma brain tumors. In this study, assay for telomerase activity performed on 50 eligible cases consisted of 26 meningioma, 24 astrocytoma according to the standard protocols. In the brain tissues, telomerase activity was positive in 39 (65 %) of 50 patients. One sample t test showed that the telomerase activity in meningioma and astrocytoma tumors was significantly positive entirely (P < 0.001). Also, grade I of meningioma and low grades of astrocytoma (grades I and II) significantly showed telomerase activity. According to our results, we suggest that activation of telomerase is an event that starts mostly at low grades of brain including meningioma and astrocytoma tumors. PMID:23512291

Kheirollahi, Majid; Mehrazin, Masoud; Kamalian, Naser; Mohammadi-asl, Javad; Mehdipour, Parvin

2013-03-20

291

A Four-Dimensional Probabilistic Atlas of the Human Brain  

PubMed Central

The authors describe the development of a four-dimensional atlas and reference system that includes both macroscopic and microscopic information on structure and function of the human brain in persons between the ages of 18 and 90 years. Given the presumed large but previously unquantified degree of structural and functional variance among normal persons in the human population, the basis for this atlas and reference system is probabilistic. Through the efforts of the International Consortium for Brain Mapping (ICBM), 7,000 subjects will be included in the initial phase of database and atlas development. For each subject, detailed demographic, clinical, behavioral, and imaging information is being collected. In addition, 5,800 subjects will contribute DNA for the purpose of determining genotype– phenotype–behavioral correlations. The process of developing the strategies, algorithms, data collection methods, validation approaches, database structures, and distribution of results is described in this report. Examples of applications of the approach are described for the normal brain in both adults and children as well as in patients with schizophrenia. This project should provide new insights into the relationship between microscopic and macroscopic structure and function in the human brain and should have important implications in basic neuroscience, clinical diagnostics, and cerebral disorders.

Mazziotta, John; Toga, Arthur; Evans, Alan; Fox, Peter; Lancaster, Jack; Zilles, Karl; Woods, Roger; Paus, Tomas; Simpson, Gregory; Pike, Bruce; Holmes, Colin; Collins, Louis; Thompson, Paul; MacDonald, David; Iacoboni, Marco; Schormann, Thorsten; Amunts, Katrin; Palomero-Gallagher, Nicola; Geyer, Stefan; Parsons, Larry; Narr, Katherine; Kabani, Noor; Le Goualher, Georges; Feidler, Jordan; Smith, Kenneth; Boomsma, Dorret; Pol, Hilleke Hulshoff; Cannon, Tyrone; Kawashima, Ryuta; Mazoyer, Bernard

2001-01-01

292

Automated regional behavioral analysis for human brain images  

PubMed Central

Behavioral categories of functional imaging experiments along with standardized brain coordinates of associated activations were used to develop a method to automate regional behavioral analysis of human brain images. Behavioral and coordinate data were taken from the BrainMap database (http://www.brainmap.org/), which documents over 20 years of published functional brain imaging studies. A brain region of interest (ROI) for behavioral analysis can be defined in functional images, anatomical images or brain atlases, if images are spatially normalized to MNI or Talairach standards. Results of behavioral analysis are presented for each of BrainMap's 51 behavioral sub-domains spanning five behavioral domains (Action, Cognition, Emotion, Interoception, and Perception). For each behavioral sub-domain the fraction of coordinates falling within the ROI was computed and compared with the fraction expected if coordinates for the behavior were not clustered, i.e., uniformly distributed. When the difference between these fractions is large behavioral association is indicated. A z-score ? 3.0 was used to designate statistically significant behavioral association. The left-right symmetry of ~100K activation foci was evaluated by hemisphere, lobe, and by behavioral sub-domain. Results highlighted the classic left-side dominance for language while asymmetry for most sub-domains (~75%) was not statistically significant. Use scenarios were presented for anatomical ROIs from the Harvard-Oxford cortical (HOC) brain atlas, functional ROIs from statistical parametric maps in a TMS-PET study, a task-based fMRI study, and ROIs from the ten “major representative” functional networks in a previously published resting state fMRI study. Statistically significant behavioral findings for these use scenarios were consistent with published behaviors for associated anatomical and functional regions.

Lancaster, Jack L.; Laird, Angela R.; Eickhoff, Simon B.; Martinez, Michael J.; Fox, P. Mickle; Fox, Peter T.

2012-01-01

293

Automated regional behavioral analysis for human brain images.  

PubMed

Behavioral categories of functional imaging experiments along with standardized brain coordinates of associated activations were used to develop a method to automate regional behavioral analysis of human brain images. Behavioral and coordinate data were taken from the BrainMap database (http://www.brainmap.org/), which documents over 20 years of published functional brain imaging studies. A brain region of interest (ROI) for behavioral analysis can be defined in functional images, anatomical images or brain atlases, if images are spatially normalized to MNI or Talairach standards. Results of behavioral analysis are presented for each of BrainMap's 51 behavioral sub-domains spanning five behavioral domains (Action, Cognition, Emotion, Interoception, and Perception). For each behavioral sub-domain the fraction of coordinates falling within the ROI was computed and compared with the fraction expected if coordinates for the behavior were not clustered, i.e., uniformly distributed. When the difference between these fractions is large behavioral association is indicated. A z-score ? 3.0 was used to designate statistically significant behavioral association. The left-right symmetry of ~100K activation foci was evaluated by hemisphere, lobe, and by behavioral sub-domain. Results highlighted the classic left-side dominance for language while asymmetry for most sub-domains (~75%) was not statistically significant. Use scenarios were presented for anatomical ROIs from the Harvard-Oxford cortical (HOC) brain atlas, functional ROIs from statistical parametric maps in a TMS-PET study, a task-based fMRI study, and ROIs from the ten "major representative" functional networks in a previously published resting state fMRI study. Statistically significant behavioral findings for these use scenarios were consistent with published behaviors for associated anatomical and functional regions. PMID:22973224

Lancaster, Jack L; Laird, Angela R; Eickhoff, Simon B; Martinez, Michael J; Fox, P Mickle; Fox, Peter T

2012-08-28

294

Cell culture: Progenitor cells from human brain after death  

NASA Astrophysics Data System (ADS)

Culturing neural progenitor cells from the adult rodent brain has become routine and is also possible from human fetal tissue, but expansion of these cells from postnatal and adult human tissue, although preferred for ethical reasons, has encountered problems. Here we describe the isolation and successful propagation of neural progenitor cells from human postmortem tissues and surgical specimens. Although the relative therapeutic merits of adult and fetal progenitor cells still need to be assessed, our results may extend the application of these progenitor cells in the treatment of neurodegenerative diseases.

Palmer, Theo D.; Schwartz, Philip H.; Taupin, Philippe; Kaspar, Brian; Stein, Stuart A.; Gage, Fred H.

2001-05-01

295

Assessing human sperm morphology: top models, underdogs or biometrics?  

PubMed Central

The assessment of the percentage of spermatozoa having an 'ideal' morphology using so-called strict method is the method recommended in the latest edition of the World Health Organization (WHO) laboratory manual for semen analysis. This recommendation is a result of the statistical association between 'ideal' sperm morphology and fertility, and of the current general belief that sperm morphology assessment should be used primarily as a fertility tool. The notion of an 'ideal' sperm morphology has persisted despite the very low percentage of such spermatozoa in the semen of fertile men, a subject of intense controversy. The detailed categorization of each abnormal spermatozoon has thus, for a long time, been considered optional and partially redundant, an idea which is reflected in the earlier editions of the WHO manual. However, several recent studies have shown the importance of carefully assessing abnormal sperm morphology for use in the diagnosis of infertility, to determine fertility prognosis, and for basic or public health studies. One approach, which combines videomicroscopy and computer vision, and is the only approach able to assess the continuum of sperm biometrics, has been used successfully in several recent clinical, basic and toxicology studies. In summary, the visual assessment of detailed sperm morphology—including the categorization of anomalies allowing arithmetically derived indices of teratozoospermia—and the more modern computer-based approaches, although often considered to be redundant, are in fact complementary. The choice of the most appropriate method depends on the field of investigation (clinical, research, toxicology) and the problem being addressed. Each approach has advantages as well as certain limitations, which will be discussed briefly herein.

Auger, Jacques

2010-01-01

296

The Human Brain Project: neuroinformatics tools for integrating, searching and modeling multidisciplinary neuroscience data  

Microsoft Academic Search

What is neuroinformatics? What is the Human Brain Project? Why should you care? Supported by a consortium of US funding agencies, the Human Brain Project aims to bring to the analysis of brain function the same advantages of Internet-accessible databases and database tools that have been crucial to the development of molecular biology and the Human Genome Project. The much

Gordon M. Shepherd; Jason S. Mirsky; Matthew D. Healy; Michael S. Singer; Emmanouil Skoufos; Michael S. Hines; Prakash M. Nadkarni; Perry L. Miller

1998-01-01

297

Gorilla and Orangutan Brains Conform to the Primate Cellular Scaling Rules: Implications for Human Evolution  

Microsoft Academic Search

Gorillas and orangutans are primates at least as large as humans, but their brains amount to about one third of the size of the human brain. This discrepancy has been used as evidence that the human brain is about 3 times larger than it should be for a primate species of its body size. In contrast to the view that

Suzana Herculano-Houzel; Jon H. Kaas

2011-01-01

298

The functional brain architecture of human morality.  

PubMed

Human morality provides the foundation for many of the pillars of society, informing political legislation and guiding legal decisions while also governing everyday social interactions. In the past decade, researchers in the field of cognitive neuroscience have made tremendous progress in the effort to understand the neural basis of human morality. The emerging insights from this research point toward a model in which automatic processing in parallel neural circuits, many of which are associated with social emotions, evaluate the actions and intentions of others. Through various mechanisms of competition, only a subset of these circuits ultimately causes a decision or an action. This activity is experienced consciously as a subjective moral sense of right or wrong, and an interpretive process offers post hoc explanations designed to link the social stimulus with the subjective moral response using whatever explicit information is available. PMID:19889532

Funk, Chadd M; Gazzaniga, Michael S

2009-11-04

299

Surface morphology and functional studies of human alveolar macrophages from cigarette smokers and nonsmokers  

SciTech Connect

The surface of macrophages inhabiting the peritoneal and alveolar spaces is pleomorphic in structure. The internal structure of these cells has been widely described and is not discussed here. Although external cell morphology has been well characterized by many researchers, this subject has not been reviewed. This review, therefore, describes in detail the surface features of macrophages as well as factors affecting macrophage morphology. Morphological studies of human cells are emphasized. Functional studies are presented and, when possible, morphological parameters are correlated with cell function. Because cigarette smoking has been well studied, the effects of this pulmonary insult are described in detail.

Finch, G.L. (Univ. of California, Berkeley); Fisher, G.L.; Hayes, T.L.; Golde, D.W.

1982-01-01

300

Human Induced Rotation and Reorganization of the Brain of Domestic Dogs  

PubMed Central

Domestic dogs exhibit an extraordinary degree of morphological diversity. Such breed-to-breed variability applies equally to the canine skull, however little is known about whether this translates to systematic differences in cerebral organization. By looking at the paramedian sagittal magnetic resonance image slice of canine brains across a range of animals with different skull shapes (N?=?13), we found that the relative reduction in skull length compared to width (measured by Cephalic Index) was significantly correlated to a progressive ventral pitching of the primary longitudinal brain axis (r?=?0.83), as well as with a ventral shift in the position of the olfactory lobe (r?=?0.81). Furthermore, these findings were independent of estimated brain size or body weight. Since brachycephaly has arisen from generations of highly selective breeding, this study suggests that the remarkable diversity in domesticated dogs' body shape and size appears to also have led to human-induced adaptations in the organization of the canine brain.

Roberts, Taryn; McGreevy, Paul; Valenzuela, Michael

2010-01-01

301

Peripheral Administration of Human Adrenomedullin and Its Binding Protein Attenuates Stroke-Induced Apoptosis and Brain Injury in Rats  

PubMed Central

Stroke is a leading cause of death and the primary medical cause of acquired adult disability worldwide. The progressive brain injury after acute stroke is partly mediated by ischemia-elicited inflammatory responses. The vasoactive hormone adrenomedullin (AM), upregulated under various inflammatory conditions, counterbalances inflammatory responses. However, regulation of AM activity in ischemic stroke remains largely unknown. Recent studies have demonstrated the presence of a specific AM binding protein (that is, AMBP-1) in mammalian blood. AMBP-1 potentiates AM biological activities. Using a rat model of focal cerebral ischemia induced by permanent middle cerebral artery occlusion (MCAO), we found that plasma levels of AM increased significantly, whereas plasma levels of AMBP-1 decreased significantly after stroke. When given peripherally early after MCAO, exogenous human AM in combination with human AMBP-1 reduced brain infarct volume 24 and 72 h after MCAO, an effect not observed after the treatment by human AM or human AMBP-1 alone. Furthermore, treatment of human AM/AMBP-1 reduced neuron apoptosis and morphological damage, inhibited neutrophil infiltration in the brain and decreased serum levels of S100B and lactate. Thus, human AM/AMBP-1 has the ability to reduce stroke-induced brain injury in rats. AM/AMBP-1 can be developed as a novel therapeutic agent for patients with ischemic stroke.

Chaung, Wayne W; Wu, Rongqian; Ji, Youxin; Wang, Zhimin; Dong, Weifeng; Cheyuo, Cletus; Qi, Lei; Qiang, Xiaoling; Wang, Haichao; Wang, Ping

2011-01-01

302

A neuronal morphologic type unique to humans and great apes  

Microsoft Academic Search

We report the existence and distribution of an unusual type of projection neuron, a large, spindle-shaped cell, in layer Vb of the anterior cingulate cortex of pongids and hominids. These spindle cells were not observed in any other primate species or any other mammalian taxa, and their volume was correlated with brain volume residuals, a measure of encephalization in higher

ESTHER A. NIMCHINSKY; E MMANUEL GILISSEN; OHN M. ALLMAN; ANIEL P. PERL; J OSEPH M. ERWIN; PATRICK R. HOF

1999-01-01

303

Multispectral Quantitative MR Imaging of the Human Brain: Lifetime Age-related Effects.  

PubMed

Quantitative magnetic resonance (MR) imaging allows visualization of age-related changes in the normal human brain from functional, biochemical, and morphologic perspectives. Findings at quantitative MR imaging support age-related microstructural changes in the brain: (a) volume expansion, increased myelination, and axonal growth, which establish neural connectivity in neurodevelopment, followed by (b) volume loss, myelin breakdown, and axonal degradation, leading to the disruption of neural integrity later in life. A rapid growth change followed by a continuous slower change in quantitative MR parameters can be modeled with a logarithmic or exponential decay function. The age dependencies during adulthood often fit a quadratic model for transitional changes with accelerated aging effects or a linear model for steady changes.Understanding these general trends over the human life span can improve assessment for a specific disease by helping determine appropriate study settings. Once a consensus on acquisition techniques and image processing algorithms has been reached, quantitative MR imaging can play an important role in the assessment of disease states affecting the brain. PMID:24025926

Watanabe, Memi; Liao, Joseph H; Jara, Hernán; Sakai, Osamu

2013-09-01

304

Sigma and opioid receptors in human brain tumors  

SciTech Connect

Human brain tumors and nude mouse-borne human neuroblastomas and gliomas were analyzed for sigma and opioid receptor content. Sigma binding was assessed using ({sup 3}H) 1, 3-di-o-tolylguanidine (DTG), whereas opioid receptor subtypes were measured with tritiated forms of the following: {mu}, (D-ala{sup 2}, mePhe{sup 4}, gly-ol{sup 5}) enkephalin (DAMGE); {kappa}, ethylketocyclazocine (EKC) or U69,593; {delta}, (D-pen{sup 2}, D-pen{sup 5}) enkephalin (DPDPE) or (D-ala{sup 2}, D-leu{sup 5}) enkephalin (DADLE) with {mu} suppressor present. Binding parameters were estimated by homologous displacement assays followed by analysis using the LIGAND program. Sigma binding was detected in 15 of 16 tumors examined with very high levels found in a brain metastasis from an adenocarcinoma of lung and a human neuroblastoma (SK-N-MC) passaged in nude mice. {kappa} opioid receptor binding was detected in 4 of 4 glioblastoma multiforme specimens and 2 of 2 human astrocytoma cell lines tested but not in the other brain tumors analyzed.

Thomas, G.E.; Szuecs, M.; Mamone, J.Y.; Bem, W.T.; Rush, M.D.; Johnson, F.E.; Coscia, C.J. (St. Louis Univ. School of Medicine, MO (USA))

1990-01-01

305

Microscopic computation in human brain evolution.  

PubMed

When human psychological performance is viewed in terms of cognitive modules, our species displays remarkable differences in computational power. Algorithmically simple computations are generally difficult to perform, whereas optimal routing or "Traveling Salesman" Problems (TSP) of far greater complexity are solved on an everyday basis. It is argued that even "simple" instances of TSP are not purely Euclidian problems in human computations, but involve emotional, autonomic, and cognitive constraints. They therefore require a level of parallel processing not possible in a macroscopic system to complete the algorithm within a brief period of time. A microscopic neurobiological model emphasizing the computational power of excited atoms within the neuronal membrane is presented as an alternative to classical connectionist approaches. The evolution of the system is viewed in terms of specific natural selection pressures driving satisfying computations toward global optimization. The relationship of microscopic computation to the nature of consciousness is examined, and possible mathematical models as a basis for simulation studies are briefly discussed. PMID:7726813

Wallace, R

1995-04-01

306

Enhanced ICBM Diffusion Tensor Template of the Human Brain  

PubMed Central

Development of a diffusion tensor (DT) template that is representative of the micro-architecture of the human brain is crucial for comparisons of neuronal structural integrity and brain connectivity across populations, as well as for the generation of a detailed white matter atlas. Furthermore, a DT template in ICBM space may simplify consolidation of information from DT, anatomical and functional MRI studies. The previously developed “IIT DT brain template” was produced in ICBM-152 space, based on a large number of subjects from a limited age-range, using data with minimal image artifacts, and non-linear registration. That template was characterized by higher image sharpness, provided the ability to distinguish smaller white matter fiber structures, and contained fewer image artifacts, than several previously published DT templates. However, low-dimensional registration was used in the development of that template, which led to a mismatch of DT information across subjects, eventually manifested as loss of local diffusion information and errors in the final tensors. Also, low-dimensional registration led to a mismatch of the anatomy in the IIT and ICBM-152 templates. In this work, a significantly improved DT brain template in ICBM-152 space was developed, using high-dimensional non-linear registration and the raw data collected for the purposes of the IIT template. The accuracy of inter-subject DT matching was significantly increased compared to that achieved for the development of the IIT template. Consequently, the new template contained DT information that was more representative of single-subject human brain data, and was characterized by higher image sharpness than the IIT template. Furthermore, a bootstrap approach demonstrated that the variance of tensor characteristics was lower in the new template. Additionally, compared to the IIT template, brain anatomy in the new template more accurately matched ICBM-152 space. Finally, spatial normalization of a number of DT datasets through registration to the new and existing IIT templates was improved when using the new template.

Zhang, Shengwei; Peng, Huiling; Dawe, Robert J.; Arfanakis, Konstantinos

2010-01-01

307

Electronic tracking of human brain samples for research  

PubMed Central

Insight into the pathogenesis of neurodegenerative disorders requires accurately categorized postmortem human brain tissue. This article introduces electronic tissue tracking and management as implemented at New York Brain Bank (NYBB) through processing of the brain at fresh state and storing standardized frozen samples. NYBB tissue tracking uses a relational database to co-register a bar coded, unique sample identifier to unique coordinates in the three-dimensional freezer space, allowing immediate retrieval of stored samples without further dissection. In the 5 years since the inception of NYBB (2002-2007) 560 brains (63,252 fresh frozen samples) were processed and as of 11/2007, 54,242 samples are stored seven freezers occupying 81% of maximum capacity of NYBB. Within the same time period, 1,094 requests were processed and 9,096 samples were disbursed with an average turnaround time of five working days. The NYBB system of brain banking has the following key advantages: (1) The dissection of the brain and the harvest of samples at the fresh state improve their anatomic specificity and quality; (2) samples are ready for immediate disbursement once categorized diagnostically, reducing the time between the receipt of request and disbursement of samples; (3) the methods prevent thaw-refreeze cycles and carving out of regions of interest from frozen tissue, which is cumbersome and deleterious to the both samples and source brains; (4) accurate quantitative data on stored samples according to anatomical regions and distributive diagnosis guides future sample collection and fosters effective use of limited resources.

Keller, Christian E.; del Pilar Amaya, Maria; Cortes, Etty Paola; Mancevska, Katerina; Vonsattel, Jean Paul G.

2009-01-01

308

Electronic tracking of human brain samples for research.  

PubMed

Insight into the pathogenesis of neurodegenerative disorders requires accurately categorized postmortem human brain tissue. This article introduces electronic tissue tracking and management as implemented at New York Brain Bank (NYBB) through processing of the brain at fresh state and storing standardized frozen samples. NYBB tissue tracking uses a relational database to co-register a bar coded, unique sample identifier to unique coordinates in the three-dimensional freezer space, allowing immediate retrieval of stored samples without further dissection. In the 5 years since the inception of NYBB (2002-2007) 560 brains (63,252 fresh frozen samples) were processed and as of 11/2007, 54,242 samples are stored seven freezers occupying 81% of maximum capacity of NYBB. Within the same time period, 1,094 requests were processed and 9,096 samples were disbursed with an average turnaround time of five working days. The NYBB system of brain banking has the following key advantages: (1) The dissection of the brain and the harvest of samples at the fresh state improve their anatomic specificity and quality; (2) samples are ready for immediate disbursement once categorized diagnostically, reducing the time between the receipt of request and disbursement of samples; (3) the methods prevent thaw-refreeze cycles and carving out of regions of interest from frozen tissue, which is cumbersome and deleterious to the both samples and source brains; (4) accurate quantitative data on stored samples according to anatomical regions and distributive diagnosis guides future sample collection and fosters effective use of limited resources. PMID:18612850

Keller, Christian E; Amaya, Maria del Pilar; Cortes, Etty Paola; Mancevska, Katerina; Vonsattel, Jean Paul G

2008-07-09

309

Human brain stem structures respond differentially to noxious heat.  

PubMed

Concerning the physiological correlates of pain, the brain stem is considered to be one core region that is activated by noxious input. In animal studies, different slopes of skin heating (SSH) with noxious heat led to activation in different columns of the midbrain periaqueductal gray (PAG). The present study aimed at finding a method for differentiating structures in PAG and other brain stem structures, which are associated with different qualities of pain in humans according to the structures that were associated with different behavioral significances to noxious thermal stimulation in animals. Brain activity was studied by functional MRI in healthy subjects in response to steep and shallow SSH with noxious heat. We found differential activation to different SSH in the PAG and the rostral ventromedial medulla (RVM). In a second experiment, we demonstrate that the different SSH were associated with different pain qualities. Our experiments provide evidence that brainstem structures, i.e., the PAG and the RVM, become differentially activated by different SSH. Therefore, different SSH can be utilized when brain stem structures are investigated and when it is aimed to activate these structures differentially. Moreover, percepts of first pain were elicited by shallow SSH whereas percepts of second pain were elicited by steep SSH. The stronger activation of these brain stem structures to SSH, eliciting percepts of second vs. first pain, might be of relevance for activating different coping strategies in response to the noxious input with the two types of SSH. PMID:24032012

Ritter, Alexander; Franz, Marcel; Dietrich, Caroline; Miltner, Wolfgang H R; Weiss, Thomas

2013-09-06

310

Human Brain Stem Structures Respond Differentially to Noxious Heat  

PubMed Central

Concerning the physiological correlates of pain, the brain stem is considered to be one core region that is activated by noxious input. In animal studies, different slopes of skin heating (SSH) with noxious heat led to activation in different columns of the midbrain periaqueductal gray (PAG). The present study aimed at finding a method for differentiating structures in PAG and other brain stem structures, which are associated with different qualities of pain in humans according to the structures that were associated with different behavioral significances to noxious thermal stimulation in animals. Brain activity was studied by functional MRI in healthy subjects in response to steep and shallow SSH with noxious heat. We found differential activation to different SSH in the PAG and the rostral ventromedial medulla (RVM). In a second experiment, we demonstrate that the different SSH were associated with different pain qualities. Our experiments provide evidence that brainstem structures, i.e., the PAG and the RVM, become differentially activated by different SSH. Therefore, different SSH can be utilized when brain stem structures are investigated and when it is aimed to activate these structures differentially. Moreover, percepts of first pain were elicited by shallow SSH whereas percepts of second pain were elicited by steep SSH. The stronger activation of these brain stem structures to SSH, eliciting percepts of second vs. first pain, might be of relevance for activating different coping strategies in response to the noxious input with the two types of SSH.

Ritter, Alexander; Franz, Marcel; Dietrich, Caroline; Miltner, Wolfgang H. R.; Weiss, Thomas

2013-01-01

311

An anatomically comprehensive atlas of the adult human brain transcriptome.  

PubMed

Neuroanatomically precise, genome-wide maps of transcript distributions are critical resources to complement genomic sequence data and to correlate functional and genetic brain architecture. Here we describe the generation and analysis of a transcriptional atlas of the adult human brain, comprising extensive histological analysis and comprehensive microarray profiling of ?900 neuroanatomically precise subdivisions in two individuals. Transcriptional regulation varies enormously by anatomical location, with different regions and their constituent cell types displaying robust molecular signatures that are highly conserved between individuals. Analysis of differential gene expression and gene co-expression relationships demonstrates that brain-wide variation strongly reflects the distributions of major cell classes such as neurons, oligodendrocytes, astrocytes and microglia. Local neighbourhood relationships between fine anatomical subdivisions are associated with discrete neuronal subtypes and genes involved with synaptic transmission. The neocortex displays a relatively homogeneous transcriptional pattern, but with distinct features associated selectively with primary sensorimotor cortices and with enriched frontal lobe expression. Notably, the spatial topography of the neocortex is strongly reflected in its molecular topography-the closer two cortical regions, the more similar their transcriptomes. This freely accessible online data resource forms a high-resolution transcriptional baseline for neurogenetic studies of normal and abnormal human brain function. PMID:22996553

Hawrylycz, Michael J; Lein, Ed S; Guillozet-Bongaarts, Angela L; Shen, Elaine H; Ng, Lydia; Miller, Jeremy A; van de Lagemaat, Louie N; Smith, Kimberly A; Ebbert, Amanda; Riley, Zackery L; Abajian, Chris; Beckmann, Christian F; Bernard, Amy; Bertagnolli, Darren; Boe, Andrew F; Cartagena, Preston M; Chakravarty, M Mallar; Chapin, Mike; Chong, Jimmy; Dalley, Rachel A; Daly, Barry David; Dang, Chinh; Datta, Suvro; Dee, Nick; Dolbeare, Tim A; Faber, Vance; Feng, David; Fowler, David R; Goldy, Jeff; Gregor, Benjamin W; Haradon, Zeb; Haynor, David R; Hohmann, John G; Horvath, Steve; Howard, Robert E; Jeromin, Andreas; Jochim, Jayson M; Kinnunen, Marty; Lau, Christopher; Lazarz, Evan T; Lee, Changkyu; Lemon, Tracy A; Li, Ling; Li, Yang; Morris, John A; Overly, Caroline C; Parker, Patrick D; Parry, Sheana E; Reding, Melissa; Royall, Joshua J; Schulkin, Jay; Sequeira, Pedro Adolfo; Slaughterbeck, Clifford R; Smith, Simon C; Sodt, Andy J; Sunkin, Susan M; Swanson, Beryl E; Vawter, Marquis P; Williams, Derric; Wohnoutka, Paul; Zielke, H Ronald; Geschwind, Daniel H; Hof, Patrick R; Smith, Stephen M; Koch, Christof; Grant, Seth G N; Jones, Allan R

2012-09-20

312

Determining the sex of human remains through cranial morphology.  

PubMed

Sex determination is the keystone of a biological profile, yet few qualitative methods of cranial sex determination have been tested. This analysis examines the accuracy and precision of 17 morphological features of the skull commonly used to determine the sex of unknown skeletal remains. The sample consists of 46 identified skulls from the 19th century St. Thomas' Anglican Church Cemetery in Belleville, Canada. Nasal aperature, zygomatic extension, malar size/rugosity, and supraorbital ridge proved the most useful; of secondary value are chin form and nuchal crest; mastoid size is of tertiary consideration; nasal size and mandibular symphysis/ramus size rank fourth; forehead shape ranks fifth; and palate size/shape are sixth. Skull size/architecture provides an internal standard to assess the relative sizes of other traits. This research is a necessary step in establishing the credibility of morphological sex determination with respect to the Daubert and Mohan criteria for admissibility in a court of law. PMID:15932077

Rogers, Tracy L

2005-05-01

313

Role of laminin and basement membrane in the morphological differentiation of human endothelial cells into capillary-like structures  

Microsoft Academic Search

We have defined a signal responsible for the morphological differentiation of human umbilical vein and human dermal microvascular endothelial cells in vitro. We find that human umbilical vein endothelial cells deprived of growth factors undergo morphologi- cal differentiation with tube formation after 6-12 wk, and that human dermal microvascular endothelial cells differentiate after 1 wk of growth factor deprivation. Here,

Yasuo Kubota; Hynda K. Kleinman; George R. Martin; Thomas J. Lawley

1988-01-01

314

Inter-brain synchronization during coordination of speech rhythm in human-to-human social interaction  

PubMed Central

Behavioral rhythms synchronize between humans for communication; however, the relationship of brain rhythm synchronization during speech rhythm synchronization between individuals remains unclear. Here, we conducted alternating speech tasks in which two subjects alternately pronounced letters of the alphabet during hyperscanning electroencephalography. Twenty pairs of subjects performed the task before and after each subject individually performed the task with a machine that pronounced letters at almost constant intervals. Speech rhythms were more likely to become synchronized in human–human tasks than human–machine tasks. Moreover, theta/alpha (6–12?Hz) amplitudes synchronized in the same temporal and lateral-parietal regions in each pair. Behavioral and inter-brain synchronizations were enhanced after human–machine tasks. These results indicate that inter-brain synchronizations are tightly linked to speech synchronizations between subjects. Furthermore, theta/alpha inter-brain synchronizations were also found in subjects while they observed human–machine tasks, which suggests that the inter-brain synchronization might reflect empathy for others' speech rhythms.

Kawasaki, Masahiro; Yamada, Yohei; Ushiku, Yosuke; Miyauchi, Eri; Yamaguchi, Yoko

2013-01-01

315

Root canal morphology of human maxillary and mandibular third molars.  

PubMed

The anatomy of third molars has been described as unpredictable. However restorative, prosthetic, and orthodontic considerations often require endodontic treatment of third molars in order for them to be retained as functional components of the dental arch. The purpose of this study was to investigate and characterize the anatomy of maxillary and mandibular third molars. One hundred fifty maxillary and 150 mandibular extracted third molars were vacuum-injected with dye, decalcified, and made transparent. The anatomy of the root canal system was then recorded. Seventeen percent of mandibular molars had one root (40% of which contained two canals), 77% had two roots, 5% had three roots, and 1% had four roots. Teeth with two roots exhibited highly variable canal morphology, containing from one to six canals, including 2.2% that were "C-shaped." Fifteen percent of maxillary molars had one root, 32% had two roots, 45% had three roots, and 7% had four roots. Teeth with one root demonstrated the most unusual morphology, with the number of canals varying from one to six. An in vivo study of the canal morphology of treated third molars is suggested to provide the practitioner with an understanding of the clinical implications of third molar root anatomy. PMID:11469300

Sidow, S J; West, L A; Liewehr, F R; Loushine, R J

2000-11-01

316

Neutral glycolipid composition of primary human brain tumors  

Microsoft Academic Search

Neutral glycolipids (NGL) were isolated and quantitated in 98 primary human brain tumors; 19 low grade astrocytomas (LGA),\\u000a 12 anaplastic astrocytomas (AA), 37 high grade astrocytomas (HGA), 18 oligodendroglial tumors, and 12 primitive neuroectodermal\\u000a tumors (PNET). In 38 of these, the nature of the hexose in the cerebroside was determined using immunothin-layer chromatographic\\u000a techniques. Galactosylceramide (GalCer) was the major ceramide

L. P. K. Singh; D. K. Pearl; T. K. Franklin; P. M. Spring; B. W. Scheithauer; S. W. Coons; P. C. Johnson; S. E. Pfeiffer; J. Li; J. C. A. Knott; A. J. Yates

1994-01-01

317

Some properties of human and bovine brain cathepsin B  

Microsoft Academic Search

Cathespin B has been purified 750-fold to apparent homogeneity from human and bovine brain cortex using ammonium sulfate fractionation (30–70%), chromatography on Sephadex G-100, CM-Sephadex C-50, and concanavalin A-Sepharose. Enzyme was assayed fluorometrically at pH 4.0 with pyridoxyl-hemoglobin in the presence of 1 mM DTT and 1 mM EDTA. Properties of the enzyme from the two sources proved to be

Anahit Azaryan; Nina Barkhudaryan; Armen Galoyan

1985-01-01

318

Interactions between cardiac, respiratory, and brain activity in humans  

Microsoft Academic Search

The electrical activity of the heart (ECG), respiratory function and electric activity of the brain (EEG) were simultaneously recorded in conscious, healthy humans. Instantaneous frequencies of the heart beat, respiration and alpha-waves were then determined from 30-minutes recordings. The instantaneous cardiac frequency was defined as the inverse value of the time interval between two consecutive R-peaks. The instantaneous respiratory frequency

Bojan Musizza; Aneta Stefanovska

2005-01-01

319

Serotonin transport kinetics correlated between human platelets and brain synaptosomes  

Microsoft Academic Search

Rationale: Blood platelets have been used ex- tensively as a model system for investigating the role of the serotonin transporter (SERT) in various psychiatric dis- orders, especially depression. However, to date, it is not knownwhetherplateletserotonin(5-HT)transportwouldbe related to that in brain. Objectives: We examined 5-HT transport kinetics simultaneously in human blood platelets andhumancorticalbrainsynaptosomestodeterminewhether they were correlated. Methods: Blood platelets and synap-

Jeffrey L. Rausch; Maria E. Johnson; Junqing Li; Julian Hutcheson; Benjamin M. Carr; Katina M. Corley; Amanda B. Gowans; Joseph Smith

2005-01-01

320

Perceptual criteria in the human brain.  

PubMed

A critical component of decision making is the ability to adjust criteria for classifying stimuli. fMRI and drift diffusion models were used to explore the neural representations of perceptual criteria in decision making. The specific focus was on the relative engagement of perceptual- and decision-related neural systems in response to adjustments in perceptual criteria. Human participants classified visual stimuli as big or small based on criteria of different sizes, which effectively biased their choices toward one response over the other. A drift diffusion model was fit to the behavioral data to extract estimates of stimulus size, criterion size, and difficulty for each participant and condition. These parameter values were used as modulated regressors to create a highly constrained model for the fMRI analysis that accounted for several components of the decision process. The results show that perceptual criteria values were reflected by activity in left inferior temporal cortex, a region known to represent objects and their physical properties, whereas stimulus size was reflected by activation in occipital cortex. A frontoparietal network of regions, including dorsolateral prefrontal cortex and superior parietal lobule, corresponded to the decision variables resulting from the downstream stimulus-criterion comparison, independent of stimulus type. The results provide novel evidence that perceptual criteria are represented in stimulus space and serve as inputs to be compared with the presented stimulus, recruiting a common network of decision regions shown to be active in other simple decisions. This work advances our understanding of the neural correlates of decision flexibility and adjustments of behavioral bias. PMID:23175825

White, Corey N; Mumford, Jeanette A; Poldrack, Russell A

2012-11-21

321

Shortcomings of the human brain and remedial action by religion  

NASA Astrophysics Data System (ADS)

There is no consensus as to whether, and if so, in which regard and to what extent science and religion is needed for human survival. Here a circumscribed domain is taken up: the sovereignty and sufficiency of the human brain in this context. Several of its shortcomings are pointed out. Religion and other aspects of culture are needed for remedial action. To determine such an action, a broad-based dialogue is required, based on the most promising ontology and epistemology as well as on appropriate logics.

Reich, K. Helmut

2010-03-01

322

Leptin plays a role in ruptured human brain arteriovenous malformations  

Microsoft Academic Search

\\u000a \\u000a Introduction  Intracerebral hemorrhage (ICH) is one of the most common clinical manifestations of human brain arteriovenous malformation\\u000a (BAVM). However, the hemorrhagic mechanism of BAVM is still unclear. Leptin, first discovered in obesity research, has not\\u000a been systematically studied in BAVM and ICH. We investigated expression and effect of leptin on human BAVM.\\u000a \\u000a \\u000a \\u000a Methods  Specimens were obtained from 6 BAVM patients, who had

Q. Xie; X. C. Chen; Y. Gong; Y. X. Gu

323

Effects of psychotropic drugs on brain plasticity in humans.  

PubMed

Although neurotransmitter-based hypotheses still prevail current thinking about the mechanism of action of psychotropic drugs, recent insight into the pathophysiology of psychiatric disorders has unveiled a range of new therapeutic actions of the drugs used to treat those disorders. Especially antidepressants seem to exert at least some of their effects via restoration of synaptic/neuronal plasticity. In addition, there is increasing evidence that several of the second-generation antipsychotics and some anticonvulsants affect neuronal survival/apoptosis as well as synaptic plasticity. Most of this evidence stems from work in animals. In this review, we will focus on the evidence for neuroplastic effects of psychotropic drugs in humans being aware of the fact that most of the data are derived from animals and that volumetric studies in humans can only indicate structural plasticity and not necessarily functional plasticity. However, as the data from human studies are rather poor and inconclusive, and sometimes even conflicting, it seems impossible to draw genereal conclusions. Until now studies on neuroplasticity in humans can only explain small pieces of the effects of pschotropic drugs on brain plasticity in humans. Nevertheless, future prospects for the development of new drugs targeting brain plasticity will be of importance and will complete this overview. PMID:23603440

Paulzen, Michael; Gründer, Gerhard

2013-04-01

324

The functional neuroanatomy of working memory: Contributions of human brain lesion studies  

Microsoft Academic Search

Studies of patients with focal brain lesions remain critical components of research programs attempting to understand human brain function. Whereas functional imaging typically reveals activity in distributed brain regions that are involved in a task, lesion studies can define which of these brain regions are necessary for a cognitive process. Further, lesion studies are less critical regarding the selection of

N. G. Müller; R. T. Knight

2006-01-01

325

Medical Imaging and the Human Brain: Being Warped is Not Always a Bad Thing  

Microsoft Academic Search

The capacity to look inside the living human brain and image its function has been present since the early 1980s. There are some clinicians who use functional brain imaging for diagnostic or prognostic purposes, but much of the work done still relates to research evaluation of brain function. There is a striking dichotomy in the use of functional brain imaging

James C. II Patterson

2005-01-01

326

Differences in the Localization and Morphology of Chromosomes in the Human Nucleus  

Microsoft Academic Search

Using fluorescence in situ hybridization we show striking differences in nuclear position, chromosome morphology, and interactions with nu- clear substructure for human chromosomes 18 and 19. Human chromosome 19 is shown to adopt a more internal position in the nucleus than chromo- some 18 and to be more extensively associated with the nuclear matrix. The more peripheral localization of chromosome

Jenny A. Croft; Joanna M. Bridger; Shelagh Boyle; Paul Perry; Peter Teague; Wendy A. Bickmore

1999-01-01

327

Detection of multiple species of human Paragonimus from Mexico using morphological data and molecular barcodes.  

PubMed

Paragonimus mexicanus is the causal agent of human paragonimiasis in several countries of the Americas. It is considered to be the only species of the genus present in Mexico, where it is responsible for human infection. Through the investigation of P. mexicanus specimens from several places throughout Mexico, we provide morphological, molecular and geographical evidence that strongly suggests the presence of at least three species from this genus in Mexico. These results raise questions regarding the diagnosis, treatment, prophylaxis and control of human paragonimiasis in Mexico. We also provide a brief discussion regarding biodiversity inventories and the convenience of providing molecular and morphological information in biodiversity studies. PMID:23530893

López-Caballero, J; Oceguera-Figueroa, A; León-Règagnon, V

2013-03-26

328

Whole transcriptome RNA-Seq allelic expression in human brain  

PubMed Central

Background Measuring allelic RNA expression ratios is a powerful approach for detecting cis-acting regulatory variants, RNA editing, loss of heterozygosity in cancer, copy number variation, and allele-specific epigenetic gene silencing. Whole transcriptome RNA sequencing (RNA-Seq) has emerged as a genome-wide tool for identifying allelic expression imbalance (AEI), but numerous factors bias allelic RNA ratio measurements. Here, we compare RNA-Seq allelic ratios measured in nine different human brain regions with a highly sensitive and accurate SNaPshot measure of allelic RNA ratios, identifying factors affecting reliable allelic ratio measurement. Accounting for these factors, we subsequently surveyed the variability of RNA editing across brain regions and across individuals. Results We find that RNA-Seq allelic ratios from standard alignment methods correlate poorly with SNaPshot, but applying alternative alignment strategies and correcting for observed biases significantly improves correlations. Deploying these methods on a transcriptome-wide basis in nine brain regions from a single individual, we identified genes with AEI across all regions (SLC1A3, NHP2L1) and many others with region-specific AEI. In dorsolateral prefrontal cortex (DLPFC) tissues from 14 individuals, we found evidence for frequent regulatory variants affecting RNA expression in tens to hundreds of genes, depending on stringency for assigning AEI. Further, we find that the extent and variability of RNA editing is similar across brain regions and across individuals. Conclusions These results identify critical factors affecting allelic ratios measured by RNA-Seq and provide a foundation for using this technology to screen allelic RNA expression on a transcriptome-wide basis. Using this technology as a screening tool reveals tens to hundreds of genes harboring frequent functional variants affecting RNA expression in the human brain. With respect to RNA editing, the similarities within and between individuals leads us to conclude that this post-transcriptional process is under heavy regulatory influence to maintain an optimal degree of editing for normal biological function.

2013-01-01

329

DISTRIBUTION OF NUCLEAR RECEPTORS FOR STEROID HORMONES IN THE HUMAN BRAIN: A PRELIMINARY STUDY  

Microsoft Academic Search

Background: Expression of the nuclear steroid hormone receptors (SHR) within certain parts of the human brain has been described by many authors. However, a comprehensive analysis of SHR expression in the human brain still has not been performed. Aim: To investigate the expression of SHR in diff erent anatomical areas of the brain, especially within the neo- cortex. Method: Immunohistochemical

M. Bezdickova; R. Molikova; L. Bebarova; Z. Kolar

2007-01-01

330

Differences between Males and Females in Rates of Serotonin Synthesis in Human Brain  

Microsoft Academic Search

Rates of serotonin synthesis were measured in the human brain using positron emission tomography. The sensitivity of the method is indicated by the fact that measurements are possible even after a substantial lowering of synthesis induced by acute tryptophan depletion. Unlike serotonin levels in human brain, which vary greatly in different brain areas, rates of synthesis of the indolamine are

S. Nishizawa; C. Benkelfat; S. N. Young; M. Leyton; S. Mzengeza; C. de Montigny; P. Blier; M. Diksic

1997-01-01

331

Functional, Morphological, and Metabolic Abnormalities of the Cerebral Microcirculation after Concussive Brain Injury in Cats  

Microsoft Academic Search

SUMMARY We induced experimental concussive brain injury by a fluid percussion device in anes- thetized cats equipped with a cranial window for the observation of the pial microcirculation of the parietal cortex. Brain injury resulted in transient but pronounced increases in arterial blood pressure and in sustained arteriolar vasodilation associated with reduced or absent responsiveness to the vasoconstrictor effect of

ENOCH P. WEI; W. DALTON DIETRICH; JOHN T. POVLISHOCK; RUDOLPH M. NAVARI; HERMES A. KONTOS

332

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

ERIC Educational Resources Information Center

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

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

2012-01-01

333

Morphological systems of human embryo assessment and clinical evidence.  

PubMed

Success rates with IVF have improved remarkably since the procedure was first established for clinical use with the first successful birth in 1978. The main goals today are to perform single-embryo transfer in order to prevent multiple pregnancies and achieve higher overall pregnancy rates. However, the ability to identify the most viable embryo in a cohort remains a challenge despite the numerous scoring systems currently in use. Clinicians still depend on developmental rate and morphological assessment using light microscopy as the first-line approach for embryo selection. Active research in the field involves developing non-invasive methods for scoring embryos and ranking them according to their ability to implant and give rise to a healthy birth. Current attention is particularly being focused on time-lapse evaluation. Available data from preliminary studies indicate that these systems are safe;prospective data now need to be collected to determine whether these methods do improve implantation rates. This review gives brief consideration to the use of morphological evaluations in assisted reproduction treatment, discusses the types of embryo scoring,digital imaging and biometric approaches currently in use and comments on future developments for embryo evaluation. PMID:23352813

Machtinger, Ronit; Racowsky, Catherine

2012-12-05

334

COMPUTER MODEL OF HUMAN LUNG MORPHOLOGY TO COMPLEMENT SPECT ANALYSES  

EPA Science Inventory

Aerosol therapy protocols could be improved if inhaled pharmacologic drugs were selectively deposited within the human lung. he targeted delivery to specific sites, such as receptors and sensitive airway cells, would enhance the efficacies of airborne pharmaceuticals. he high res...

335

Classifying human brain tumors by lipid imaging with mass spectrometry.  

PubMed

Brain tissue biopsies are required to histologically diagnose brain tumors, but current approaches are limited by tissue characterization at the time of surgery. Emerging technologies such as mass spectrometry imaging can enable a rapid direct analysis of cancerous tissue based on molecular composition. Here, we illustrate how gliomas can be rapidly classified by desorption electrospray ionization-mass spectrometry (DESI-MS) imaging, multivariate statistical analysis, and machine learning. DESI-MS imaging was carried out on 36 human glioma samples, including oligodendroglioma, astrocytoma, and oligoastrocytoma, all of different histologic grades and varied tumor cell concentration. Gray and white matter from glial tumors were readily discriminated and detailed diagnostic information could be provided. Classifiers for subtype, grade, and concentration features generated with lipidomic data showed high recognition capability with more than 97% cross-validation. Specimen classification in an independent validation set agreed with expert histopathology diagnosis for 79% of tested features. Together, our findings offer proof of concept that intraoperative examination and classification of brain tissue by mass spectrometry can provide surgeons, pathologists, and oncologists with critical and previously unavailable information to rapidly guide surgical resections that can improve management of patients with malignant brain tumors. PMID:22139378

Eberlin, Livia S; Norton, Isaiah; Dill, Allison L; Golby, Alexandra J; Ligon, Keith L; Santagata, Sandro; Cooks, R Graham; Agar, Nathalie Y R

2011-12-02

336

Biological and morphological characterization of human neonatal fibroblast cell culture B-HNF-1  

Microsoft Academic Search

In the present study, human neonatal fibroblasts were isolated from a two-month-old human male. The purpose of the present\\u000a investigation was the analysis of the morphology (light and transmission electron microscopy), karyotype and growth characteristics\\u000a of the human neonatal fibroblast cell culture B-HNF-1. Moreover, STR typing and mitochondrial DNA amplification and sequencing\\u000a was also performed. Analysis of chromosomes count showed

Vanda Repiská; Ivan Varga; Ivan Lehocký; Daniel Böhmer; Milan Blaško; Štefan Polák; Marián Adamkov; ?uboš Danišovi?

2010-01-01

337

Effects of human placental serum on proliferation and morphology of human adipose tissue-derived stem cells  

Microsoft Academic Search

Media used for tissue culture may have significant effects on the growth and morphology of the adipose tissue-derived stem cells (ADSCs). As fetal bovine serum (FBS) may induce an immunological reaction and health risks, this study was designed to evaluate and compare the effects of human placental serum (HPS) on the proliferation and morphology of hADSCs. We cultured hADSCs for

H Shafaei; A Esmaeili; M Mardani; S Razavi; B Hashemibeni; M H Nasr-Esfahani; M B Shiran; E Esfandiari

2011-01-01

338

Neuroergonomics - Analyzing Brain Function to Enhance Human Performance in Complex Systems.  

National Technical Information Service (NTIS)

Why Neuroergonomics. To design effective human-machine systems, we must (1) Understand mind in relation to work and technology -- ergonomics (2) Mind cannot be understood without studying the brain -- neuroscience (3) Hence study brain and mind in complex...

R. Parasuraman

2008-01-01

339

The early development and evolution of the human brain.  

PubMed

THE CHEMISTRY OF THE BRAIN: The brain and nervous system is characterised by a heavy investment in lipid chemistry which accounts for up to 60% of its structural material. In the different mammalian species so far studied, only the 20 and 22 carbon chain length polyenoic fatty acids were present and the balance of the n-3 to n-6 fatty acids was consistently 1:1. The difference observed between species, was not in the chemistry but in the extent to which the brain is developed. This paper discusses the possibility that essential fatty acids may have played a part in it evolution. THE ORIGIN OF AIR BREATHING ANIMALS: The first phase of the planet's existence indulged in high temperature reactions in which oxygen combined with everything feasible: from silicon to make rocks to hydrogen to make water. Once the planet's temperature dropped to a point at which water could condense on the surface allowing chemical reactions to take place in it. The atmosphere was at that time devoid of oxygen so life evolved in a reducing atmosphere. Oxygen was liberated by photolysis of water and as a by-product of the blue-green algae through photosynthesis. When the point was reached at which oxidative metabolism became thermodynamically possible, animal life evolved with all the principle phyla establishing themselves within a relatively short space of geological time. (Bernal 1973). DHA and nerve cell membranes DHA AND NERVE CELL MEMBRANES: From the chemistry of contemporary algae it is likely that animal life evolved in an n-3 rich environment although not exclusively so as smaller amounts of n-6 fatty acids would have been present. A key feature of the first animals was the evolution of the photoreceptor: in examples of marine, amphibian and modern mammalian species, it has been found to use docosahexaenoic acid (DHA) as the principle membrane fatty acid in the phosphoglycerides. It is likely that the first animals did so as well. Coincidentally, the synaptic membranes involved in signal transduction also use high proportions of n-3 fatty acids. However, the n-6 fatty acids also find a place, in the inositol phosphoglyceride (IPG) which appears to be involved with calcium ion transport and hence signal activation and reception. Even in the photoreceptor, the IPG is an arachidonic acid rich phosphoglyceride. THE EVOLUTION OF MAMMALS AND THE LARGE BRAIN: The dominance of n-3 fatty acids in the food chain, persisted until the end of the Cretaceous period when the flowering plants followed on the disappearance of the giant cycads and ferns. A new set of species, the mammals, then evolved with a requirement for n-6 fatty acids for reproduction. This dependance was coincident with the flowering plants which for the first time produced protected seeds: these introduced a rich source of n-6 fatty acids. The brain size of the mammals tended to be relatively larger (that is in relation to body size) by comparison with the previous reptilian or egg laying systems. This process led to the large human brain. A crucial difference between man and other animals, is undoubtedly the extent to which the brain and its peripheral attributes have been developed. This paper will address the possibility that the potential for the evolution of the large human brain may have been released by the evolving human primate occupying an ecological niche which offered a rich source of those nutrients specifically required for the brain. That niche is at the land/water interface. PMID:2077700

Crawford, M A

1990-01-01

340

The Attention System of the Human Brain: 20 Years After  

PubMed Central

Here, we update our 1990 Annual Review of Neuroscience article, “The Attention System of the Human Brain.” The framework presented in the original article has helped to integrate behavioral, systems, cellular, and molecular approaches to common problems in attention research. Our framework has been both elaborated and expanded in subsequent years. Research on orienting and executive functions has supported the addition of new networks of brain regions. Developmental studies have shown important changes in control systems between infancy and childhood. In some cases, evidence has supported the role of specific genetic variations, often in conjunction with experience, that account for some of the individual differences in the efficiency of attentional networks. The findings have led to increased understanding of aspects of pathology and to some new interventions.

Petersen, Steven E.; Posner, Michael I.

2012-01-01

341

Morphological variation in dentate and edentulous human mandibles  

Microsoft Academic Search

Purpose  The aim of the study was to examine the different morphometric variations of the human mandibles, comparing between males\\u000a and females in dentate and edentulous mandibles.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Eighty adult human dry mandibles were studied. Thirty-two variations were evaluated according to the presence and absence\\u000a of teeth. Kolmogorov–Smirnov test was performed to evaluate the normal distribution of the morphometric variables. Levene\\u000a test

Bruno Ramos Chrcanovic; Mauro Henrique Nogueira Guimarães Abreu; Antônio Luís Neto Custódio

2011-01-01

342

Brain-Based Learning: The Neurological Findings About the Human Brain that Every Teacher Should Know to be Effective  

Microsoft Academic Search

The purpose of this paper is to present the main neurological findings about the human brain that provide the basis for brain-based learning, and that represent a narrow field of cognitive science as a whole. The findings that are described were made primarily by neuroscientists who studied the structure and functions of the nervous system with the purpose of correcting

Ronald Jean Degen

2011-01-01

343

Morphology of human intracardiac nerves: an electron microscope study  

PubMed Central

Since many human heart diseases involve both the intrinsic cardiac neurons and nerves, their detailed normal ultrastructure was examined in material from autopsy cases without cardiac complications obtained no more than 8 h after death. Many intracardiac nerves were covered by epineurium, the thickness of which was related to nerve diameter. The perineurial sheath varied from nerve to nerve and, depending on nerve diameter, contained up to 12 layers of perineurial cells. The sheaths of the intracardiac nerves therefore become progressively attenuated during their course in the heart. The intraneural capillaries of the human heart differ from those in animals in possessing an increased number of endothelial cells. A proportion of the intraneural capillaries were fenestrated. The number of unmyelinated axons within unmyelinated nerve fibres was related to nerve diameter, thin cardiac nerves possessing fewer axons. The most distinctive feature was the presence of stacks of laminated Schwann cell processes unassociated with axons that were more frequent in older subjects. Most unmyelinated and myelinated nerve fibres showed normal ultrastructure, although a number of profiles displayed a variety of different axoplasmic contents. Collectively, the data provide baseline information on the normal structure of intracardiac nerves in healthy humans which may be useful for assessing the degree of nerve damage both in autonomic and sensory neuropathies in the human heart.

PAUZIENE, NERINGA; PAUZA, DAINIUS H.; STROPUS, RIMVYDAS

2000-01-01

344

An efficient algorithm in extracting human iris Morphological features  

Microsoft Academic Search

The interface of computer technologies and biology is having a huge impact on society. Human recognition research projects promises new life to many security-consulting firms and personal identification system manufacturers. Iris recognition is considered to be the most reliable biometric authentication system. Very few iris recognition algorithms were commercialized. The method proposed in this paper differed from the existing work

Mohamed A. Mohamed; M. E. A. Abou-Elsoud; M. M. Eid

2009-01-01

345

Morphology of the osteonal cement line in human bone  

Microsoft Academic Search

While current consensus suggests the absence of collagen in osteonal cement lines, the extent of cement line mineralization and the nature of the ground substance within the cement line are unclear. Samples of human radius were examined by using scanning electron microscopy, electron microprobe, and histochemical techniques. X-ray intensities were used to compare the amount of calcium, phosphorus, and sulfur

Mitchell B. Schaffler; David B. Burr; Richard G. Frederickson

1987-01-01

346

Evolution of the base of the brain in highly encephalized human species.  

PubMed

The increase of brain size relative to body size-encephalization-is intimately linked with human evolution. However, two genetically different evolutionary lineages, Neanderthals and modern humans, have produced similarly large-brained human species. Thus, understanding human brain evolution should include research into specific cerebral reorganization, possibly reflected by brain shape changes. Here we exploit developmental integration between the brain and its underlying skeletal base to test hypotheses about brain evolution in Homo. Three-dimensional geometric morphometric analyses of endobasicranial shape reveal previously undocumented details of evolutionary changes in Homo sapiens. Larger olfactory bulbs, relatively wider orbitofrontal cortex, relatively increased and forward projecting temporal lobe poles appear unique to modern humans. Such brain reorganization, beside physical consequences for overall skull shape, might have contributed to the evolution of H. sapiens' learning and social capacities, in which higher olfactory functions and its cognitive, neurological behavioral implications could have been hitherto underestimated factors. PMID:22158443

Bastir, Markus; Rosas, Antonio; Gunz, Philipp; Peña-Melian, Angel; Manzi, Giorgio; Harvati, Katerina; Kruszynski, Robert; Stringer, Chris; Hublin, Jean-Jacques

2011-12-13

347

Infection and upregulation of proinflammatory cytokines in human brain vascular pericytes by human cytomegalovirus  

PubMed Central

Background Congenital human cytomegalovirus (HCMV) infections can result in CNS abnormalities in newborn babies including vision loss, mental retardation, motor deficits, seizures, and hearing loss. Brain pericytes play an essential role in the development and function of the blood–brain barrier yet their unique role in HCMV dissemination and neuropathlogy has not been reported. Methods Primary human brain vascular pericytes were exposed to a primary clinical isolate of HCMV designated ‘SBCMV’. Infectivity was analyzed by microscopy, immunofluorescence, Western blot, and qRT-PCR. Microarrays were performed to identify proinflammatory cytokines upregulated after SBCMV exposure, and the results validated by real-time quantitative polymerase chain reaction (qPCR) methodology. In situ cytokine expression of pericytes after exposure to HCMV was examined by ELISA and in vivo evidence of HCMV infection of brain pericytes was shown by dual-labeled immunohistochemistry. Results HCMV-infected human brain vascular pericytes as evidenced by several markers. Using a clinical isolate of HCMV (SBCMV), microscopy of infected pericytes showed virion production and typical cytomegalic cytopathology. This finding was confirmed by the expression of major immediate early and late virion proteins and by the presence of HCMV mRNA. Brain pericytes were fully permissive for CMV lytic replication after 72 to 96 hours in culture compared to human astrocytes or human brain microvascular endothelial cells (BMVEC). However, temporal transcriptional expression of pp65 virion protein after SBCMV infection was lower than that seen with the HCMV Towne laboratory strain. Using RT-PCR and dual-labeled immunofluorescence, proinflammatory cytokines CXCL8/IL-8, CXCL11/ITAC, and CCL5/Rantes were upregulated in SBCMV-infected cells, as were tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1beta), and interleukin-6 (IL-6). Pericytes exposed to SBCMV elicited higher levels of IL-6 compared to both mock-infected as well as heat-killed virus controls. A 6.6-fold induction of IL-6 and no induction TNF-alpha was observed in SBCMV-infected cell supernatants at 24 hours postinfection. Using archival brain tissue from a patient coinfected with HCMV and HIV, we also found evidence of HCMV infection of pericytes using dual-label immunohistochemistry, as monitored by NG2 proteoglycan staining. Conclusion HCMV lytic infection of primary human brain pericytes suggests that pericytes contribute to both virus dissemination in the CNS as well as neuroinflammation.

2012-01-01

348

Morphological lesions in the brain preceding the development of postischemic seizures  

Microsoft Academic Search

This study explores how hyperglycemia and enhanced tissue lactic acidosis influence the density and distribution of ischemic brain damage. Ischemia of 10-min duration was produced in glucose-infused rats by bilateral carotid clamping combined with hypotension, and the brains were perfusion-fixed with formaldehyde following recirculation of 3, 6, 12 and 18 h. After about 24 h the hyperglycemic animals developed seizures,

M.-L. Smith; H. Kalimo; D. S. Warner; B. K. Siesjö

1988-01-01

349

Brain morphological changes associated with exposure to HSV1 in first-episode schizophrenia  

Microsoft Academic Search

Infectious agents have been proposed as one of the risk factors for schizophrenia. However, the data on the association of infectious agents with in vivo brain changes are scant. We evaluated the association of serological evidence of exposure to herpes simplex virus 1 (HSV1) with in vivo brain structural variations among first-episode antipsychotic-naive schizophrenia\\/schizoaffective disorder patients and control subjects. We

K M R Prasad; B H Shirts; R H Yolken; M S Keshavan; V L Nimgaonkar; KMR Prasad

2007-01-01

350

Accelerated evolution of the ASPM gene controlling brain size begins prior to human brain expansion.  

PubMed

Primary microcephaly (MCPH) is a neurodevelopmental disorder characterized by global reduction in cerebral cortical volume. The microcephalic brain has a volume comparable to that of early hominids, raising the possibility that some MCPH genes may have been evolutionary targets in the expansion of the cerebral cortex in mammals and especially primates. Mutations in ASPM, which encodes the human homologue of a fly protein essential for spindle function, are the most common known cause of MCPH. Here we have isolated large genomic clones containing the complete ASPM gene, including promoter regions and introns, from chimpanzee, gorilla, orangutan, and rhesus macaque by transformation-associated recombination cloning in yeast. We have sequenced these clones and show that whereas much of the sequence of ASPM is substantially conserved among primates, specific segments are subject to high Ka/Ks ratios (nonsynonymous/synonymous DNA changes) consistent with strong positive selection for evolutionary change. The ASPM gene sequence shows accelerated evolution in the African hominoid clade, and this precedes hominid brain expansion by several million years. Gorilla and human lineages show particularly accelerated evolution in the IQ domain of ASPM. Moreover, ASPM regions under positive selection in primates are also the most highly diverged regions between primates and nonprimate mammals. We report the first direct application of TAR cloning technology to the study of human evolution. Our data suggest that evolutionary selection of specific segments of the ASPM sequence strongly relates to differences in cerebral cortical size. PMID:15045028

Kouprina, Natalay; Pavlicek, Adam; Mochida, Ganeshwaran H; Solomon, Gregory; Gersch, William; Yoon, Young-Ho; Collura, Randall; Ruvolo, Maryellen; Barrett, J Carl; Woods, C Geoffrey; Walsh, Christopher A; Jurka, Jerzy; Larionov, Vladimir

2004-03-23

351

Distribution of vesicular monoamine transporter 2 protein in human brain: implications for brain imaging studies  

PubMed Central

The choice of reference region in positron emission tomography (PET) human brain imaging of the vesicular monoamine transporter 2 (VMAT2), a marker of striatal dopamine innervation, has been arbitrary, with cerebellar, whole cerebral, frontal, or occipital cortices used. To establish whether levels of VMAT2 are in fact low in these cortical areas, we measured VMAT2 protein distribution by quantitative immunoblotting in autopsied normal human brain (n=6). Four or five species of VMAT2 immunoreactivity (75, 55, 52, 45, 35?kDa) were detected, which were all markedly reduced in intensity in nigrostriatal regions of patients with parkinsonian conditions versus matched controls (n=9 to 10 each). Using the intact VMAT2 immunoreactivity, cerebellar and cerebral neocortices had levels of the transporter >100-fold lower than the VMAT2-rich striatum and with no significant differences among the cortical regions. We conclude that human cerebellar and cerebral cortices contain negligible VMAT2 protein versus the striatum and, in this respect, all satisfy a criterion for a useful reference region for VMAT2 imaging. The slightly lower PET signal for VMAT2 binding in occipital (the currently preferred reference region) versus cerebellar cortex might not therefore be explained by differences in VMAT2 protein itself but possibly by other imaging variables, for example, partial volume effects.

Tong, Junchao; Boileau, Isabelle; Furukawa, Yoshiaki; Chang, Li-Jan; Wilson, Alan A; Houle, Sylvain; Kish, Stephen J

2011-01-01

352

Morphological findings in the brain after experimental gunshots using radiology, pathology and histology.  

PubMed

The tissue disruption inside the brain after experimental gunshots to the head was investigated with special reference to secondary bone missiles and intracranial pressure effects such as cortical contusion and deep intracerebral haemorrhages. The evidential value of various examination methods is compared. 9 mm Parabellum ammunition was fired to the temporal region of calves (n = 10) from a distance of 0-10 cm. Plain film radiography, CT, MRI, visual inspection and histology were performed on every brain. The tissue disruption of the permanent tract is delineated best by artefact-free MRI. Cortical contusions and deep intracerebral haemorrhages were detected infrequently by visual inspection and imaging techniques although they were present in every brain as verified by histology. These injuries remote from the tract increase cerebral wounding compared to non-confined tissue. In particular, the brain stem and central areas were frequent sites of haemorrhages, which can be expected to have serious and immediate consequences. Ectopic bone fragments were found in all brains using CT scans. Bone fragments were located inside clearly enlarged permanent tracts or were driven into brain tissue. In the latter cases, secondary shot channels up to 4 cm in length could be verified by histology. Cortical contusions and intracerebral haemorrhages can only be detected reliably by histology. The localization of bone fragments requires CT scans. Therefore, a detailed examination is accomplished best by a combination of the methods applied in this study. PMID:9826091

Karger, B; Puskas, Z; Ruwald, B; Teige, K; Schuirer, G

1998-01-01

353

Brain cDNA clone for human cholinesterase  

SciTech Connect

A cDNA library from human basal ganglia was screened with oligonucleotide probes corresponding to portions of the amino acid sequence of human serum cholinesterase. Five overlapping clones, representing 2.4 kilobases, were isolated. The sequenced cDNA contained 207 base pairs of coding sequence 5' to the amino terminus of the mature protein in which there were four ATG translation start sites in the same reading frame as the protein. Only the ATG coding for Met-(-28) lay within a favorable consensus sequence for functional initiators. There were 1722 base pairs of coding sequence corresponding to the protein found circulating in human serum. The amino acid sequence deduced from the cDNA exactly matched the 574 amino acid sequence of human serum cholinesterase, as previously determined by Edman degradation. Therefore, our clones represented cholinesterase rather than acetylcholinesterase. It was concluded that the amino acid sequences of cholinesterase from two different tissues, human brain and human serum, were identical. Hybridization of genomic DNA blots suggested that a single gene, or very few genes coded for cholinesterase.

McTiernan, C.; Adkins, S.; Chatonnet, A.; Vaughan, T.A.; Bartels, C.F.; Kott, M.; Rosenberry, T.L.; La Du, B.N.; Lockridge, O.

1987-10-01

354

Biochemical and morphological investigations of 30 human insulinomas  

Microsoft Academic Search

Summary  Thirty human insulinomas have been investigated histologically and their immunoreactive insulin (IRI) content estimated. In most cases immunohistological and ultrastructural studies were also performed and the percentage of proinsulin-like components (PLC) in the tumour determined. Except for 1 case the IRI concentration in the tumours was lower (0.01–89.0 U\\/g) than in the islet tissue. Histologically, immunohistologically and ultrastructurally a variable

W. Creutzfeldt; R. Arnold; C. Creutzfeldt; U. Deuticke; H. Frerichs; N. S. Track

1973-01-01

355

Medullo-ponto-cerebellar white matter degeneration altered brain network organization and cortical morphology in multiple system atrophy.  

PubMed

The cerebellum involves diverse functions from motor coordination to higher cognitive functions. Impairment of the cerebellum can cause ataxia and cerebellar cognitive affective syndrome. Multiple system atrophy of the cerebellar type (MSA-C) is a neurodegenerative disorder with atrophy of medullo-ponto-cerebellar (MPC) white matter (WM). To understand the role of the cerebellum from the perspective of the local structure to the global function in the presence of MPC WM degeneration, we acquired T1-weighted and diffusion tensor images for 17 patients with MSA-C and 19 normal controls. We concurrently used the measures of local morphology, including MPC WM volume and inner surface area, and properties of global network organization based on graph theory for the MSA-C and control groups. The results showed that MPC WM degeneration caused the destruction of cerebello-ponto-cerebral loops, resulting in reduced communication efficiency between regions in the whole-brain network. In addition, the sulcal area of the inner cortical surface in the cerebellum decreased linearly with the MPC WM volume, and the inferoposterior lobe exhibited a steeper atrophy rate than that of vermis regions. We concluded that the integrity of MPC WM is critical in sustaining the local morphology and the global functions of the whole-brain fiber network. PMID:23636223

Lu, Chia-Feng; Wang, Po-Shan; Lao, Yuan-Lin; Wu, Hsiu-Mei; Soong, Bing-Wen; Wu, Yu-Te

2013-05-01

356

Some properties of human and bovine brain cathepsin B  

Microsoft Academic Search

Cathespin B has been purified 750-fold to apparent homogeneity from human and bovine brain cortex using ammonium sulfate fractionation\\u000a (30–70%), chromatography on Sephadex G-100, CM-Sephadex C-50, and concanavalin A-Sepharose. Enzyme was assayed fluorometrically\\u000a at pH 4.0 with pyridoxyl-hemoglobin in the presence of 1 mM DTT and 1 mM EDTA. Properties of the enzyme from the two sources\\u000a proved to be

Anahit Azaryan; Nina Barkhudaryan; Armen Galoyan

1985-01-01

357

The brain's silent messenger: using selective attention to decode human thought for brain-based communication.  

PubMed

The interpretation of human thought from brain activity, without recourse to speech or action, is one of the most provoking and challenging frontiers of modern neuroscience. In particular, patients who are fully conscious and awake, yet, due to brain damage, are unable to show any behavioral responsivity, expose the limits of the neuromuscular system and the necessity for alternate forms of communication. Although it is well established that selective attention can significantly enhance the neural representation of attended sounds, it remains, thus far, untested as a response modality for brain-based communication. We asked whether its effect could be reliably used to decode answers to binary (yes/no) questions. Fifteen healthy volunteers answered questions (e.g., "Do you have brothers or sisters?") in the fMRI scanner, by selectively attending to the appropriate word ("yes" or "no"). Ninety percent of the answers were decoded correctly based on activity changes within the attention network. The majority of volunteers conveyed their answers with less than 3 min of scanning, suggesting that this technique is suited for communication in a reasonable amount of time. Formal comparison with the current best-established fMRI technique for binary communication revealed improved individual success rates and scanning times required to detect responses. This novel fMRI technique is intuitive, easy to use in untrained participants, and reliably robust within brief scanning times. Possible applications include communication with behaviorally nonresponsive patients. PMID:23719806

Naci, Lorina; Cusack, Rhodri; Jia, Vivian Z; Owen, Adrian M

2013-05-29

358

The Representation of Biological Classes in the Human Brain  

PubMed Central

Evidence of category specificity from neuroimaging in the human visual system is generally limited to a few relatively coarse categorical distinctions—e.g., faces versus bodies, or animals versus artifacts—leaving unknown the neural underpinnings of fine-grained category structure within these large domains. Here we use functional magnetic resonance imaging (fMRI) to explore brain activity for a set of categories within the animate domain, including six animal species—two each from three very different biological classes: primates, birds, and insects. Patterns of activity throughout ventral object vision cortex reflected the biological classes of the stimuli. Specifically, the abstract representational space—measured as dissimilarity matrices defined between species-specific multivariate patterns of brain activity—correlated strongly with behavioral judgments of biological similarity of the same stimuli. This biological class structure was uncorrelated with structure measured in retinotopic visual cortex, which correlated instead with a dissimilarity matrix defined by a model of V1 cortex for the same stimuli. Additionally, analysis of the shape of the similarity space in ventral regions provides evidence for a continuum in the abstract representational space—with primates at one end and insects at the other. Further investigation into the cortical topography of activity that contributes to this category structure reveals the partial engagement of brain systems active normally for inanimate objects in addition to animate regions.

Connolly, Andrew C.; Guntupalli, J. Swaroop; Gors, Jason; Hanke, Michael; Halchenko, Yaroslav O.; Wu, Yu-Chien; Abdi, Herv?e; Haxby, James V.

2012-01-01

359

Heritability of human brain functioning as assessed by electroencephalography.  

PubMed Central

To study the genetic and environmental contributions to individual differences in CNS functioning, the electroencephalogram (EEG) was measured in 213 twin pairs age 16 years. EEG was measured in 91 MZ and 122 DZ twins. To quantify sex differences in the genetic architecture, EEG was measured in female and male same-sex twins and in opposite-sex twins. EEG was recorded on 14 scalp positions during quiet resting with eyes closed. Spectral powers were calculated for four frequency bands: delta, theta, alpha, and beta. Twin correlations pointed toward high genetic influences for all these powers and scalp locations. Model fitting confirmed these findings; the largest part of the variance of the EEG is explained by additive genetic factors. The averaged heritabilites for the delta, theta, alpha and beta frequencies was 76%, 89%, 89%, and 86%, respectively. Multivariate analyses suggested that the same genes for EEG alpha rhythm were expressed in different brain areas in the left and right hemisphere. This study shows that brain functioning, as indexed by rhythmic brain-electrical activity, is one of the most heritable characteristics in humans.

van Beijsterveldt, C. E.; Molenaar, P. C.; de Geus, E. J.; Boomsma, D. I.

1996-01-01

360

The human brain-from cells to society.  

PubMed

In December 2011, the European Science Foundation (ESF) brought together experts from a wide range of disciplines to discuss the issues that will influence the development of a healthier, more brain-aware European society. This perspective summarizes the main outcomes of that discussion and highlights important considerations to support improved mental health in Europe, including: The development of integrated neuropsychotherapeutic approaches to the treatment of psychiatric disorders.The development of more valid disease models for research into psychiatric disorders.An improved understanding of the relationship between biology and environment, particularly in relation to developmental plasticity and emerging pathology.More comparative studies to explore how scientific concepts relating to the human brain are received and understood in different sociocultural contexts.Research into the legal and ethical implications of recent developments in the brain sciences, including behavioral screening and manipulation, and emerging neurotechnologies. The broad geographical spread of the consulted experts across the whole of Europe, along with the wide range of disciplines they represent, gives these conclusions a strong scientific and pan-European endorsement. The next step will be to look closely into these five selected topics, in terms of research strategy, science policy, societal implications, and legal and ethical frameworks. PMID:23966920

Hoogland, Eva; Patten, Iain; Berghmans, Stephane

2013-08-07

361

The runner's high: opioidergic mechanisms in the human brain.  

PubMed

The runner's high describes a euphoric state resulting from long-distance running. The cerebral neurochemical correlates of exercise-induced mood changes have been barely investigated so far. We aimed to unravel the opioidergic mechanisms of the runner's high in the human brain and to identify the relationship to perceived euphoria. We performed a positron emission tomography "ligand activation" study with the nonselective opioidergic ligand 6-O-(2-[(18)F]fluoroethyl)-6-O-desmethyldiprenorphine ([(18)F]FDPN). Ten athletes were scanned at 2 separate occasions in random order, at rest and after 2 h of endurance running (21.5 +/- 4.7 km). Binding kinetics of [(18)F]FDPN were quantified by basis pursuit denoising (DEPICT software). Statistical parametric mapping (SPM2) was used for voxelwise analyses to determine relative changes in ligand binding after running and correlations of opioid binding with euphoria ratings. Reductions in opioid receptor availability were identified preferentially in prefrontal and limbic/paralimbic brain structures. The level of euphoria was significantly increased after running and was inversely correlated with opioid binding in prefrontal/orbitofrontal cortices, the anterior cingulate cortex, bilateral insula, parainsular cortex, and temporoparietal regions. These findings support the "opioid theory" of the runner's high and suggest region-specific effects in frontolimbic brain areas that are involved in the processing of affective states and mood. PMID:18296435

Boecker, Henning; Sprenger, Till; Spilker, Mary E; Henriksen, Gjermund; Koppenhoefer, Marcus; Wagner, Klaus J; Valet, Michael; Berthele, Achim; Tolle, Thomas R

2008-02-21

362

Constructing a dictionary of human brain folding patterns.  

PubMed

Brain imaging provides a wealth of information that computers can explore at a massive scale. Categorizing the patterns of the human cortex has been a challenging issue for neuroscience. In this paper, we propose a data mining approach leading to the construction of the first computerized dictionary of cortical folding patterns, from a database of 62 brains. The cortical folds are extracted using BrainVisa open software. The standard sulci are manually identified among the folds. 32 sets of sulci covering the cortex are selected. Clustering techniques are further applied to identify in each set the different patterns observed in the population. After affine global normalization, the geometric distance between sulci of two subjects is calculated using the Iterative Closest Point (ICP) algorithm. The dimension of the resulting distance matrix is reduced using Isomap algorithm. Finally, a dedicated hierarchical clustering algorithm is used to extract out the main patterns. This algorithm provides a score which evaluates the strengths of the patterns found. The score is used to rank the patterns for setting up a dictionary to characterize the variability of cortical anatomy. PMID:20426103

Sun, Zhong Yi; Perrot, Matthieu; Tucholka, Alan; Rivière, Denis; Mangin, Jean-François

2009-01-01

363

Effects of physical activity on cognition, well-being, and brain: Human interventions  

Microsoft Academic Search

This article provides a review of the human intervention literature that has examined the influence of fitness training on cognition, well-being, brain structure, and brain function. Meta-analyses of this literature, which are reviewed here, suggest robust effects of fitness training on cognition and well-being. Although there are currently few human intervention studies that have examined fitness effects on human brain

Arthur F. Kramer; Kirk I. Erickson

2007-01-01

364

Receptors for advanced glycosylation endproducts in human brain: role in brain homeostasis.  

PubMed Central

BACKGROUND: Advanced glycation end products (AGEs) are the reactive derivatives of nonenzymatic glucose-macromolecule condensation products. Aging human tissues accumulate AGEs in an age-dependent manner and contribute to age-related functional changes in vital organs. We have shown previously that AGE scavenger receptors are present on monocyte/macrophages, lymphocytes, and other cells. However, it remains unclear whether the human brain can efficiently eliminate AGE-modified proteins and whether excessive AGEs can contribute to inflammatory changes leading to brain injury in aging. MATERIALS AND METHODS: To explore the expression and characteristics of AGE-binding proteins on CNS glia components and their putative function, such as degradation of AGE-modified proteins, primary human astrocytes and human monocytes (as a microglial cell surrogate) and murine microglia (N9) cells and cell membrane extracts were used. Immunohistochemistry was used to examine the distribution of AGE-binding proteins in the human hippocampus; RT-PCR techniques were used to examine the biologic effects of AGEs and a model AGE compound, FFI, on AGE-binding protein modulation and cytokine responses of human astrocytes and monocytes. RESULTS: Our results showed that AGE-binding proteins AGE-R1, -R2, and -R3 are present in glial cells. Western blot analyses and radiolabeled ligand binding studies show that AGE-R1 and -R3 from human astrocytes bind AGE-modified proteins; binding could be blocked by anti-AGE-R1 and anti-AGE-R3 antibodies, respectively. Immunohistochemistry showed that AGE-R1 and -R2 are expressed mainly in neurons; only some glial cells express these AGE-binding proteins. In contrast, AGE-R3 was found only on those astrocytes whose positively stained foot processes extend and surround the sheath of microcapillaries. RT-PCR results showed that mRNAs of the three AGE-binding proteins are expressed constitutively in human astrocytes and monocytes, and receptor transcripts are not regulated by exogenous AGEs, the model AGE compound FFI, or phorbol ester. At the concentrations used, GM-CSF appears to be the only cytokine whose transcript and protein levels are regulated in human astrocytes by exogenous AGEs. CONCLUSIONS: The selective presence of AGE-binding proteins in pyramidal neurons and glial cells and their roles in degrading AGE-modified protein in glial cells suggest that the human brain has a mechanism(s) to clear AGE-modified proteins. Without this capacity, accumulation of AGEs extracellularly could stimulate glial cells to produce the major inflammatory cytokine GM-CSF, which has been shown to be capable of up-regulating AGE-R3. It remains to be determined whether AGE-binding proteins could be aberrant or down-regulated under certain pathological conditions, resulting in an insidious inflammatory state of the CNS in some aging humans. Images Fig. 1 Fig. 3 Fig. 4 Fig. 5

Li, J. J.; Dickson, D.; Hof, P. R.; Vlassara, H.

1998-01-01

365

Concentration of Nucleosides and Related Compounds in Cerebral and Cerebellar Cortical Areas and White Matter of the Human Brain  

Microsoft Academic Search

  1. Nucleosides potentially participate in the neuronal functions of the brain. However, their distribution and changes in their concentrations in the human brain is not known. For better understanding of nucleoside functions, changes of nucleoside concentrations by age and a complete map of nucleoside levels in the human brain are actual requirements.2. We used post mortem human brain samples in

Katalin A. Kékesi; Zsolt Kovács; Nóra Szilágyi; Mátyás Bobest; Tamás Szikra; Árpád Dobolyi; Gábor Juhász; Miklós Palkovits

2006-01-01

366

Ablation of the mTORC2 component rictor in brain or Purkinje cells affects size and neuron morphology  

PubMed Central

The mammalian target of rapamycin (mTOR) assembles into two distinct multi-protein complexes called mTORC1 and mTORC2. Whereas mTORC1 is known to regulate cell and organismal growth, the role of mTORC2 is less understood. We describe two mouse lines that are devoid of the mTORC2 component rictor in the entire central nervous system or in Purkinje cells. In both lines neurons were smaller and their morphology and function were strongly affected. The phenotypes were accompanied by loss of activation of Akt, PKC, and SGK1 without effects on mTORC1 activity. The striking decrease in the activation and expression of several PKC isoforms, the subsequent loss of activation of GAP-43 and MARCKS, and the established role of PKCs in spinocerebellar ataxia and in shaping the actin cytoskeleton strongly suggest that the morphological deficits observed in rictor-deficient neurons are mediated by PKCs. Together our experiments show that mTORC2 has a particularly important role in the brain and that it affects size, morphology, and function of neurons.

Thomanetz, Venus; Angliker, Nico; Cloetta, Dimitri; Lustenberger, Regula M.; Schweighauser, Manuel; Oliveri, Filippo; Suzuki, Noboru

2013-01-01

367

Ablation of the mTORC2 component rictor in brain or Purkinje cells affects size and neuron morphology.  

PubMed

The mammalian target of rapamycin (mTOR) assembles into two distinct multi-protein complexes called mTORC1 and mTORC2. Whereas mTORC1 is known to regulate cell and organismal growth, the role of mTORC2 is less understood. We describe two mouse lines that are devoid of the mTORC2 component rictor in the entire central nervous system or in Purkinje cells. In both lines neurons were smaller and their morphology and function were strongly affected. The phenotypes were accompanied by loss of activation of Akt, PKC, and SGK1 without effects on mTORC1 activity. The striking decrease in the activation and expression of several PKC isoforms, the subsequent loss of activation of GAP-43 and MARCKS, and the established role of PKCs in spinocerebellar ataxia and in shaping the actin cytoskeleton strongly suggest that the morphological deficits observed in rictor-deficient neurons are mediated by PKCs. Together our experiments show that mTORC2 has a particularly important role in the brain and that it affects size, morphology, and function of neurons. PMID:23569215

Thomanetz, Venus; Angliker, Nico; Cloëtta, Dimitri; Lustenberger, Regula M; Schweighauser, Manuel; Oliveri, Filippo; Suzuki, Noboru; Rüegg, Markus A

2013-04-08

368

Brain morphological abnormalities in 49,XXXXY syndrome: A pediatric magnetic resonance imaging study???  

PubMed Central

As a group, people with the sex chromosome aneuploidy 49,XXXXY have characteristic physical and cognitive/behavioral tendencies, although there is high individual variation. In this study we use magnetic resonance imaging (MRI) to examine brain morphometry in 14 youth with 49,XXXXY compared to 42 age-matched healthy controls. Total brain size was significantly smaller (t = 9.0, p < .001), and rates of brain abnormalities such as colpocephaly, plagiocephaly, periventricular cysts, and minor craniofacial abnormalities were significantly increased. White matter lesions were identified in 50% of subjects, supporting the inclusion of 49,XXXXY in the differential diagnosis of small multifocal white matter lesions. Further evidence of abnormal development of white matter was provided by the smaller cross sectional area of the corpus callosum. These results suggest that increased dosage of genes on the X chromosome has adverse effects on white matter development.

Blumenthal, Jonathan D.; Baker, Eva H.; Lee, Nancy Raitano; Wade, Benjamin; Clasen, Liv S.; Lenroot, Rhoshel K.; Giedd, Jay N.

2013-01-01

369

Influence of nanoparticles of platinum on chicken embryo development and brain morphology  

NASA Astrophysics Data System (ADS)

Platinum nanoparticles (NP-Pt) are noble metal nanoparticles with unique physiochemical properties that have recently elicited much interest in medical research. However, we still know little about their toxicity and influence on general health. We investigated effects of NP-Pt on the growth and development of the chicken embryo model with emphasis on brain tissue micro- and ultrastructure. The embryos were administered solutions of NP-Pt injected in ovo at concentrations from 1 to 20 ?g/ml. The results demonstrate that NP-Pt did not affect the growth and development of the embryos; however, they induced apoptosis and decreased the number of proliferating cells in the brain tissue. These preliminary results indicate that properties of NP-Pt might be utilized in brain cancer therapy, but potential toxic side effects must be elucidated in extensive follow-up research.

Prasek, Marta; Sawosz, Ewa; Jaworski, Slawomir; Grodzik, Marta; Ostaszewska, Teresa; Kamaszewski, Maciej; Wierzbicki, Mateusz; Chwalibog, Andre

2013-05-01

370

Selectively altering belief formation in the human brain  

PubMed Central

Humans form beliefs asymmetrically; we tend to discount bad news but embrace good news. This reduced impact of unfavorable information on belief updating may have important societal implications, including the generation of financial market bubbles, ill preparedness in the face of natural disasters, and overly aggressive medical decisions. Here, we selectively improved people’s tendency to incorporate bad news into their beliefs by disrupting the function of the left (but not right) inferior frontal gyrus using transcranial magnetic stimulation, thereby eliminating the engrained “good news/bad news effect.” Our results provide an instance of how selective disruption of regional human brain function paradoxically enhances the ability to incorporate unfavorable information into beliefs of vulnerability.

Sharot, Tali; Kanai, Ryota; Marston, David; Korn, Christoph W.; Rees, Geraint; Dolan, Raymond J.

2012-01-01

371

Frequency representation within the human brain: Stability versus plasticity  

PubMed Central

A topographical representation for frequency has been identified throughout the auditory brain in animals but with limited evidence in humans. Using a midbrain implant, we identified an ordering of pitch percepts for electrical stimulation of sites across the human inferior colliculus (IC) that was consistent with the IC tonotopy shown in animals. Low pitches were perceived by the subject for stimulation of superficial IC sites while higher pitches were perceived for stimulation of deeper sites. Interestingly, this pitch ordering was not initially observed for stimulation across the IC, possibly due to central changes caused by prior hearing loss. Daily implant stimulation for about 4?months altered the pitch percepts from being predominantly low to exhibiting the expected ordering across the stimulated IC. A presumably normal tonotopic representation may have been maintained within the IC or accessible through IC stimulation that helped form this pitch ordering perceived in higher centers.

Lim, Hubert H.; Lenarz, Minoo; Joseph, Gert; Lenarz, Thomas

2013-01-01

372

Coronal in vivo forward-imaging of rat brain morphology with an ultra-small optical coherence tomography fiber probe  

NASA Astrophysics Data System (ADS)

A well-established navigation method is one of the key conditions for successful brain surgery: it should be accurate, safe and online operable. Recent research shows that optical coherence tomography (OCT) is a potential solution for this application by providing a high resolution and small probe dimension. In this study a fiber-based spectral-domain OCT system utilizing a super-luminescent-diode with the center wavelength of 840 nm providing 14.5 ?m axial resolution was used. A composite 125 ?m diameter detecting probe with a gradient index (GRIN) fiber fused to a single mode fiber was employed. Signals were reconstructed into grayscale images by horizontally aligning A-scans from the same trajectory with different depths. The reconstructed images can display brain morphology along the entire trajectory. For scans of typical white matter, the signals showed a higher reflection of light intensity with lower penetration depth as well as a steeper attenuation rate compared to the scans typical for gray matter. Micro-structures such as axon bundles (70 ?m) in the caudate nucleus are visible in the reconstructed images. This study explores the potential of OCT to be a navigation modality in brain surgery.

Xie, Yijing; Bonin, Tim; Löffler, Susanne; Hüttmann, Gereon; Tronnier, Volker; Hofmann, Ulrich G.

2013-02-01

373

Neurons Express Hemoglobin ?- and ?-Chains in Rat and Human Brains  

PubMed Central

Hemoglobin is the oxygen carrier in vertebrate blood erythrocytes. Here we report that hemoglobin chains are expressed in mammalian brain neurons and are regulated by a mitochondrial toxin. Transcriptome analyses of laser-capture microdissected nigral dopaminergic neurons in rats and striatal neurons in mice revealed the presence of hemoglobin ?, adult chain 2 (Hba-a2) and hemoglobin ? (Hbb) transcripts, whereas other erythroid markers were not detected. Quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) analysis confirmed the expression of Hba-a2 and Hbb in nigral dopaminergic neurons, striatal ?-aminobutyric acid (GABA)ergic neurons, and cortical pyramidal neurons in rats. Combined in situ hybridization histochemistry and immunohistochemistry with the neuronal marker neuronal nuclear antigen (NeuN) in rat brain further confirmed the presence of hemoglobin mRNAs in neurons. Immunohistochemistry identified hemoglobin ?- and ?-chains in both rat and human brains, and hemoglobin proteins were detected by Western blotting in whole rat brain tissue as well as in cultures of mesencephalic neurons, further excluding the possibility of blood contamination. Systemic administration of the mitochondrial inhibitor rotenone (2 mg/kg/d, 7d, s.c.) induced a marked decrease in Hba-a2 and Hbb but not neuroglobin or cytoglobin mRNA in transcriptome analyses of nigral dopaminergic neurons. Quantitative RT-PCR confirmed the transcriptional downregulation of Hba-a2 and Hbb in nigral, striatal, and cortical neurons. Thus, hemoglobin chains are expressed in neurons and are regulated by treatments that affect mitochondria, opening up the possibility that they may play a novel role in neuronal function and response to injury.

RICHTER, FRANZISKA; MEURERS, BERNHARD H.; ZHU, CHUNNI; MEDVEDEVA, VERA P.; CHESSELET, MARIE-FRANCOISE

2011-01-01

374

Telomere Length Modulation in Human Astroglial Brain Tumors  

PubMed Central

Background Telomeres alteration during carcinogenesis and tumor progression has been described in several cancer types. Telomeres length is stabilized by telomerase (h-TERT) and controlled by several proteins that protect telomere integrity, such as the Telomere Repeat-binding Factor (TRF) 1 and 2 and the tankyrase-poli-ADP-ribose polymerase (TANKs-PARP) complex. Objective To investigate telomere dysfunction in astroglial brain tumors we analyzed telomeres length, telomerase activity and the expression of a panel of genes controlling the length and structure of telomeres in tissue samples obtained in vivo from astroglial brain tumors with different grade of malignancy. Materials and Methods Eight Low Grade Astrocytomas (LGA), 11 Anaplastic Astrocytomas (AA) and 11 Glioblastoma Multiforme (GBM) samples were analyzed. Three samples of normal brain tissue (NBT) were used as controls. Telomeres length was assessed through Southern Blotting. Telomerase activity was evaluated by a telomere repeat amplification protocol (TRAP) assay. The expression levels of TRF1, TRF2, h-TERT and TANKs-PARP complex were determined through Immunoblotting and RT-PCR. Results LGA were featured by an up-regulation of TRF1 and 2 and by shorter telomeres. Conversely, AA and GBM were featured by a down-regulation of TRF1 and 2 and an up-regulation of both telomerase and TANKs-PARP complex. Conclusions In human astroglial brain tumours, up-regulation of TRF1 and TRF2 occurs in the early stages of carcinogenesis determining telomeres shortening and genomic instability. In a later stage, up-regulation of PARP-TANKs and telomerase activation may occur together with an ADP-ribosylation of TRF1, causing a reduced ability to bind telomeric DNA, telomeres elongation and tumor malignant progression.

La Torre, Domenico; Conti, Alfredo; Aguennouz, M?Hammed; De Pasquale, Maria Grazia; Romeo, Sara; Angileri, Filippo Flavio; Cardali, Salvatore; Tomasello, Chiara; Alafaci, Concetta; Germano, Antonino

2013-01-01

375

Neuronal avalanches in the resting MEG of the human brain.  

PubMed

What constitutes normal cortical dynamics in healthy human subjects is a major question in systems neuroscience. Numerous in vitro and in vivo animal studies have shown that ongoing or resting cortical dynamics are characterized by cascades of activity across many spatial scales, termed neuronal avalanches. In experiment and theory, avalanche dynamics are identified by two measures: (1) a power law in the size distribution of activity cascades with an exponent of -3/2 and (2) a branching parameter of the critical value of 1, reflecting balanced propagation of activity at the border of premature termination and potential blowup. Here we analyzed resting-state brain activity recorded using noninvasive magnetoencephalography (MEG) from 124 healthy human subjects and two different MEG facilities using different sensor technologies. We identified large deflections at single MEG sensors and combined them into spatiotemporal cascades on the sensor array using multiple timescales. Cascade size distributions obeyed power laws. For the timescale at which the branching parameter was close to 1, the power law exponent was -3/2. This relationship was robust to scaling and coarse graining of the sensor array. It was absent in phase-shuffled controls with the same power spectrum or empty scanner data. Our results demonstrate that normal cortical activity in healthy human subjects at rest organizes as neuronal avalanches and is well described by a critical branching process. Theory and experiment have shown that such critical, scale-free dynamics optimize information processing. Therefore, our findings imply that the human brain attains an optimal dynamical regime for information processing. PMID:23595765

Shriki, Oren; Alstott, Jeff; Carver, Frederick; Holroyd, Tom; Henson, Richard N A; Smith, Marie L; Coppola, Richard; Bullmore, Edward; Plenz, Dietmar

2013-04-17

376

Neuronal Avalanches in the Resting MEG of the Human Brain  

PubMed Central

What constitutes normal cortical dynamics in healthy human subjects is a major question in systems neuroscience. Numerous in vitro and in vivo animal studies have shown that ongoing or resting cortical dynamics are characterized by cascades of activity across many spatial scales, termed neuronal avalanches. In experiment and theory, avalanche dynamics are identified by two measures: (1) a power law in the size distribution of activity cascades with an exponent of ?3/2 and (2) a branching parameter of the critical value of 1, reflecting balanced propagation of activity at the border of premature termination and potential blowup. Here we analyzed resting-state brain activity recorded using noninvasive magnetoencephalography (MEG) from 124 healthy human subjects and two different MEG facilities using different sensor technologies. We identified large deflections at single MEG sensors and combined them into spatiotemporal cascades on the sensor array using multiple timescales. Cascade size distributions obeyed power laws. For the timescale at which the branching parameter was close to 1, the power law exponent was ?3/2. This relationship was robust to scaling and coarse graining of the sensor array. It was absent in phase-shuffled controls with the same power spectrum or empty scanner data. Our results demonstrate that normal cortical activity in healthy human subjects at rest organizes as neuronal avalanches and is well described by a critical branching process. Theory and experiment have shown that such critical, scale-free dynamics optimize information processing. Therefore, our findings imply that the human brain attains an optimal dynamical regime for information processing.

Shriki, Oren; Alstott, Jeff; Carver, Frederick; Holroyd, Tom; Henson, Richard N.A.; Smith, Marie L.; Coppola, Richard; Bullmore, Edward; Plenz, Dietmar

2013-01-01

377

Morphological studies of the developing human esophageal epithelium.  

PubMed

This article focusses on the structural development of human esophageal ciliated epithelium. A combination of transmission electron microscopic (TEM), scanning electron microscopic (SEM), radioautographic, and light microscopic (LM) analyses were carried out using intact fetal tissues between 8 and 20 weeks of gestation as well as cultured esophageal explants. Up to the age of 10 weeks, the stratified esophageal epithelium consisted of two longitudinal primary folds. The surface cells were undifferentiated and contained large glycogen aggregates. Between 11 and 16 weeks, the primary folds (now up to four) had developed secondary folds. The thickness of the epithelium drastically increased (123%) in concomittance with a differentiation of surface columnar ciliated cells. These highly specialized surface cells exhibited junctional complexes and well-developed organelles with numerous microvilli interspersed among the cilia. Transverse sections revealed the internal structure of the cilia with a consistent pattern of nine doublet microtubules surrounding a central pair of single microtubules. Freeze-fracture studies illustrated the presence of a ciliary necklace composed of 6 ring-like rows of intramembranous particles. They also revealed the structure of ciliary cell tight junctions consisting of up to nine anastomosing strands (P-face) or complementary grooves (E-face). Ultrastructural studies (LM, TEM, SEM) of the esophageal squamous epithelium obtained after 15 days of culture showed that the newly formed epithelium was similar to adult human epithelium. Finally LM and SEM observations established that the esophagogastric junction was not yet well delineated, consisting of a transitional area composed of a mixture of esophageal ciliated cells and gastric columnar mucous cells. PMID:7670160

Ménard, D

1995-06-15

378

Mass spectrometry quantification of clusterin in the human brain  

PubMed Central

Background The multifunctional glycoprotein clusterin has been associated with late-onset Alzheimer’s disease (AD). Further investigation to define the role of clusterin in AD phenotypes would be aided by the development of techniques to quantify level, potential post-translational modifications, and isoforms of clusterin. We have developed a quantitative technique based on multiple reaction monitoring (MRM) mass spectrometry to measure clusterin in human postmortem brain tissues. Results A stable isotope-labeled concatenated peptide (QconCAT) bearing selected peptides from clusterin was expressed with an in vitro translation system and purified. This clusterin QconCAT was validated for use as an internal standard for clusterin quantification using MRM mass spectrometry. Measurements were performed on the human postmortem frontal and temporal cortex from control and severe AD cases. During brain tissues processing, 1% SDS was used in the homogenization buffer to preserve potential post-translational modifications of clusterin. However, MRM quantifications in the brain did not suggest phosphorylation of Thr393, Ser394, and Ser396 residues reported for clusterin in serum. MRM quantifications in the frontal cortex demonstrated significantly higher (P?

2012-01-01

379

Live morphological analysis of taxol-induced cytoplasmic vacuoliazation in human lung adenocarcinoma cells  

Microsoft Academic Search

Taxol (paclitaxel), one of the most active cancer chemotherapeutic agents, can cause programmed cell death (PCD) and cytoplasmic vacuolization. The objective of this study was to analyze the morphological characteristics induced by taxol. Human lung adenocarcinoma (ASTC-a-1) cells were exposed to various concentration of taxol. CCK-8 was used to assay the cell viability. Atomic force microscopy (AFM), plasmid transfection and

Xiao-Ping Wang; Tong-Sheng Chen; Lei Sun; Ji-Ye Cai; Ming-Qian Wu; Martin Mok

2008-01-01

380

Morphological and stance interpolations in database for simulating bipedalism of virtual humans  

Microsoft Academic Search

We present a computer tool for testing walk hypotheses for human beings. This tool aims to generate plausible walking movements according to anatomical knowledge. To this end, we introduce an interpolation method based, on one hand, on morphological data and, on the other hand, on stance hypotheses and on footprint hypotheses. We want to test these hypotheses for application to

Nicolas Pronost; Georges Dumont; Gilles Berillon; Guillaume Nicolas

2006-01-01

381

Morphological and anthropological aspects of human triangular deciduous lower first molar teeth  

Microsoft Academic Search

The crown and root morphology, and bilateral occurrence of human deciduous lower first molars that exhibited a triangular occlusal outline, taken from excavated samples of Japanese, Jomonese and Iraqi origin, were investigated. The crowns of triangular teeth had smaller mesiodistal and larger buccolingual diameters than normally shaped deciduous lower first molars. An elongated buccolingual diameter was derived from the buccal

Yoshikazu Kitagawa; Yoshitaka Manabe; Joichi Oyamada; Atsushi Rokutanda

1996-01-01

382

Developmental Morphological and Histological Studies on Structures of the Human Fetal Shoulder Joint  

Microsoft Academic Search

In the present work, morphological changes in the interior structures of the developing human shoulder joint were studied at different prenatal ages (9, 12, 16, 23 and 40 weeks) and were compared with the same structures in the adult joint. It was found that the shoulder joint had gone through important developmental changes during the 12th week of the prenatal

Laila M. Aboul Mahasen; Sohair A. Sadek

2002-01-01

383

Developmental Morphological and Histological Studies on Structures of the Human Fetal Elbow Joint  

Microsoft Academic Search

In the present work, morphological changes in the developing human elbow joint were studied at different prenatal ages (8, 12, 16, 20, 29 and 40 weeks) and were compared with the same structures in the adult joint. The elbow joint had gone through its most important developmental changes during the 20th week of prenatal life, probably due to the direct

Laila M. Aboul Mahasen; Sohair A. Sadek

2000-01-01

384

A morphologic study of unfertilized oocytes and abnormal embryos in human in vitro fertilization  

Microsoft Academic Search

The morphology of human, unfertilized oocytes and abnormal embryos cultured in vitro for 48–72 hr was examined in an attempt to learn more about oocyte maturation and reproductive failure in in vitro fertilization (IVF). About 21% of the unfertilized oocytes were totally degenerated. The majority (56%) of the remaining oocytes was arrested at the metaphase II stage. They contained coherent

Hanna Ba?akier; Robert F. Casper

1991-01-01

385

Variation of cell and matrix morphologies in articular cartilage among locations in the adult human knee  

Microsoft Academic Search

Summary Objective: Understanding of articular cartilage physiology, remodelling mechanisms, and evaluation of tissue engineering repair methods requires reference information regarding normal structural organization. Our goals were to examine the variation of cartilage cell and matrix morphology in different topographical areas of the adult human knee joint. Methods: Osteochondral explants were acquired from seven distinct anatomical locations of the knee joints

Thomas M. Quinn; Ernst B. Hunziker; Hans-Jörg Häuselmann

2005-01-01

386

Human breast areolae as scent organs: Morphological data and possible involvement in maternal-neonatal coadaptation  

Microsoft Academic Search

In humans, areolar skin glands (AG) enlarge during pregnancy and lactation. Their role in mother-infant interactions may pertain to protective, mechanical, and communicative functions. It was questioned here whether more profuse AG could be related to more optimal adaptation to breastfeeding. A morphological study of the areolae was undertaken between birth and day 3 to assess the number, secretory status,

Benoist Schaal; Sébastien Doucet; Paul Sagot; Elisabeth Hertling; Robert Soussignan

2006-01-01

387

Chromosome abnormalities and their relationship to morphology and development of human embryos  

Microsoft Academic Search

This review covers the relationship between chromosome abnormalities, morphological abnormalities and embryonic development. The baseline of chromosome abnormalities in human embryos produced by assisted reproduction is higher than 50%, regardless of maternal age. While aneuploidy increases with maternal age, abnormalities arising post-meiotically, such as mosaicism, chaoticism, polyploidy and haploidy, have similar incidence in all age groups (about 33%). Post-meiotic abnormalities

Santiago Munné

2006-01-01

388

Brain asymmetry is encoded at the level of axon terminal morphology  

Microsoft Academic Search

BACKGROUND: Functional lateralization is a conserved feature of the central nervous system (CNS). However, underlying left-right asymmetries within neural circuitry and the mechanisms by which they develop are poorly described. RESULTS: In this study, we use focal electroporation to examine the morphology and connectivity of individual neurons of the lateralized habenular nuclei. Habenular projection neurons on both sides of the

Isaac H Bianco; Matthias Carl; Claire Russell; Jonathan DW Clarke; Stephen W Wilson

2008-01-01

389

Segmentation of Brain Structures by Watershed Transform on Tensorial Morphological Gradient of Diffusion Tensor Imaging  

Microsoft Academic Search

Watershed transform on tensorial morphological gradient (TMG) is a new approach to segment diffusion tensor images (DTI). Since the TMG is able to express the tenso- rial dissimilarities in a single scalar image, the segmentation problem of DTI is then reduced to a scalar image segmenta- tion problem. Therefore, it can be addressed by well-known segmentation techniques, such as the

Leticia Rittner; Simone Appenzeller; Roberto De Alencar Lotufo

2009-01-01

390

Shape versus Size: Improved Understanding of the Morphology of Brain Structures  

Microsoft Academic Search

Standard practice in quantitative structural neuroimaging is a segmentation into brain tissue, subcortical structures, fluid space and lesions followed by volume calculations of gross structures. On the other hand, it is evident that object characterization by size does only capture one of multiple aspects of a full structural characterization. Desirable parameters are local and global parameters like length, elongation, bending,

Guido Gerig; Martin Styner; Martha Elizabeth Shenton; Jeffrey A. Lieberman

2001-01-01

391

Clock Drawing Performance and Brain Morphology in Mild Cognitive Impairment and Alzheimer's Disease  

ERIC Educational Resources Information Center

|The Clock Drawing Test (CDT) is a widely used instrument in the neuropsychological assessment of Alzheimer's disease (AD). As CDT performance necessitates several cognitive functions (e.g., visuospatial and constructional abilities, executive functioning), an interaction of multiple brain regions is likely. Fifty-one subjects with mild cognitive…

Thomann, Philipp A.; Toro, Pablo; Santos, Vasco Dos; Essig, Marco; Schroder, Johannes

2008-01-01

392

Diversification of brain morphology in antarctic notothenioid fishes: Basic descriptions and ecological considerations  

Microsoft Academic Search

The Notothenioidei, a perciform suborder of 120 species, domi- nates the ichthyofauna of the Southern Ocean around Antarctica. Unlike most teleost groups, notothenioids have undergone a corresponding ecological and phyletic diversification and therefore provide an excellent opportunity to study the divergence of the nervous system in an unusual environment. Our goal is to evaluate notothenioid brain variation in light of

Joseph T. Eastman; Michael J. Lannoo

1995-01-01

393

Clock Drawing Performance and Brain Morphology in Mild Cognitive Impairment and Alzheimer's Disease  

ERIC Educational Resources Information Center

The Clock Drawing Test (CDT) is a widely used instrument in the neuropsychological assessment of Alzheimer's disease (AD). As CDT performance necessitates several cognitive functions (e.g., visuospatial and constructional abilities, executive functioning), an interaction of multiple brain regions is likely. Fifty-one subjects with mild cognitive…

Thomann, Philipp A.; Toro, Pablo; Santos, Vasco Dos; Essig, Marco; Schroder, Johannes

2008-01-01

394

Hyaluronan and collagen in human hypertrophic cardiomyopathy: a morphological analysis.  

PubMed

Introduction. The hypertrophic cardiomyopathy (HCM) disease process is not only limited to cardiomyocyte abnormalities but also engages the extracellular matrix. Hyaluronan (HA) and its receptor CD44 are involved in cellular growth and tissue proliferation but have so far been less studied in myocardial hypertrophy. In HCM, collagens are abundant but their histological distribution and relation to hyaluronan have not been described. Material and Methods. Myocardial specimens from 5 patients with symptomatic left ventricular tract obstruction undergoing myectomy due to HCM were processed for histochemistry and immunohistochemistry. Results. HA staining was more intense in HCM patients. The histological distribution of HA was the same in patients and controls, that is, interstitial staining including the space between cardiomyocytes, in fibrous septa, and in the adventitia of intramyocardial blood vessels. CD44 was not detected in the myocardium of patients or controls. Collagen I showed the same general localisation as HA but detailed distribution differed. Conclusions. This is the first study that describes the distribution of hyaluronan in human HCM. HA staining is more intense in HCM patients but without coexpression of its receptor CD44, at least not in the chronic phase of HCM. HA and collagen I have the same localisation. PMID:22900226

Hellström, Martin; Engström-Laurent, Anna; Mörner, Stellan; Johansson, Bengt

2012-07-26

395

Gender-Specific Gene Expression in Post-Mortem Human Brain: Localization to Sex Chromosomes  

Microsoft Academic Search

Gender differences in brain development and in the prevalence of neuropsychiatric disorders such as depression have been reported. Gender differences in human brain might be related to patterns of gene expression. Microarray technology is one useful method for investigation of gene expression in brain. We investigated gene expression, cell types, and regional expression patterns of differentially expressed sex chromosome genes

Marquis P Vawter; Simon Evans; Prabhakara Choudary; Hiroaki Tomita; Jim Meador-Woodruff; Margherita Molnar; Jun Li; Juan F Lopez; Rick Myers; David Cox; Stanley J Watson; Huda Akil; Edward G Jones; William E Bunney

2004-01-01

396

The Partition of Trace Amounts of Xenon Between Human Blood and Brain Tissues at 37°C  

Microsoft Academic Search

The relative solubilities of trace amounts of 133Xe at 37° C in human plasma, red blood cells, grey and white matter of the brain, and in homogenized whole brain have been determined. From these data the tissue\\/blood partition coefficients for cortex, white matter and whole brain have been calculated as a function of haematocrit. On the basis of the measured

N. Veall; B. L. Mallett

1965-01-01

397

A Twin MRI Study of Size Variations in the Human Brain  

Microsoft Academic Search

Although it is well known that there is considerable variation among individuals in the size of the human brain, the etiology of less extreme individual differences in brain size is largely unknown. We present here data from the first large twin sample (N=132 individuals) in which the size of brain structures has been measured. As part of an ongoing project

Bruce F. Pennington; Pauline A. Filipek; Dianne Lefly; Nomita Chhabildas; David N. Kennedy; Jack H. Simon; Christopher M. Filley; Albert Galaburda; John C. DeFries

2000-01-01

398

Brain Expression Genome-Wide Association Study (eGWAS) Identifies Human Disease-Associated Variants  

Microsoft Academic Search

Genetic variants that modify brain gene expression may also influence risk for human diseases. We measured expression levels of 24,526 transcripts in brain samples from the cerebellum and temporal cortex of autopsied subjects with Alzheimer's disease (AD, cerebellar n = 197, temporal cortex n = 202) and with other brain pathologies (non–AD, cerebellar n = 177, temporal cortex n =

Fanggeng Zou; High Seng Chai; Curtis S. Younkin; Mariet Allen; Julia Crook; V. Shane Pankratz; Minerva M. Carrasquillo; Christopher N. Rowley; Asha A. Nair; Sumit Middha; Sooraj Maharjan; Thuy Nguyen; Li Ma; Kimberly G. Malphrus; Ryan Palusak; Sarah Lincoln; Gina Bisceglio; Constantin Georgescu; Naomi Kouri; Christopher P. Kolbert; Jin Jen; Jonathan L. Haines; Richard Mayeux; Margaret A. Pericak-Vance; Lindsay A. Farrer; Gerard D. Schellenberg; Ronald C. Petersen; Neill R. Graff-Radford; Dennis W. Dickson; Steven G. Younkin; Nilüfer Ertekin-Taner

2012-01-01

399

The Organization of Local and Distant Functional Connectivity in the Human Brain  

Microsoft Academic Search

Information processing in the human brain arises from both interactions between adjacent areas and from distant projections that form distributed brain systems. Here we map interactions across different spatial scales by estimating the degree of intrinsic functional connectivity for the local (?14 mm) neighborhood directly surrounding brain regions as contrasted with distant (>14 mm) interactions. The balance between local and

Jorge Sepulcre; Hesheng Liu; Tanveer Talukdar; Iñigo Martincorena; B. T. Thomas Yeo; Randy L. Buckner

2010-01-01

400

A Celebration of Neurons: An Educator's Guide to the Human Brain.  

ERIC Educational Resources Information Center

This book provides an introduction to the current scientific understanding of the human brain and its processes. Chapter 1, "At the Edge of a Major Transformation," is an introduction to the field. Chapter 2, "How Our Brain Organizes Itself on the Cellular and Systems Levels," covers what body/brain cellular systems do, how cells process units of…

Sylwester, Robert

401

Quantitation of human brain GABA A receptor ? isoforms by competitive RT–PCR  

Microsoft Academic Search

We have developed a competitive RT–PCR assay, adapted from Lewohl et al. [Brain Res. Brain Res. Protoc. 1 (1997) 347], for the quantitation of GABAA receptor ? isoforms in human brain using an internal standard that shares high sequence homology to the targets. The internal standard is identical to the ?1 sequence except for a 61 bp deletion and the

S. Tracey Buckley; Peter R. Dodd

2003-01-01

402

Bmi1 marks intermediate precursors during differentiation of human brain tumor initiating cells  

Microsoft Academic Search

The master regulatory gene Bmi1 modulates key stem cell properties in neural precursor cells (NPCs), and has been implicated in brain tumorigenesis. We previously identified a population of CD133+ brain tumor cells possessing stem cell properties, known as brain tumor initiating cells (BTICs). Here, we characterize the expression and role of Bmi1 in primary minimally cultured human glioblastoma (GBM) patient

Chitra Venugopal; Na Li; Xin Wang; Branavan Manoranjan; Cynthia Hawkins; Thorsteinn Gunnarsson; Robert Hollenberg; Paula Klurfan; Naresh Murty; Jacek Kwiecien; Forough Farrokhyar; John P. Provias; Christopher Wynder; Sheila K. Singh

403

Autoradiographic analysis of alpha 1-noradrenergic receptors in the human brain postmortem. Effect of suicide  

Microsoft Academic Search

In vitro quantitative autoradiography of alpha 1-noradrenergic receptors, using tritiated prazosin as a ligand, was performed on 24 human brains postmortem. Twelve brains were obtained from suicide victims and 12 from matched controls. We found significant lower binding to alpha 1 receptors in several brain regions of the suicide group as compared with matched controls. This decrease in receptor density

R. Gross-Isseroff; K. A. Dillon; S. J. Fieldust; A. Biegon

1990-01-01

404

MR methods for studying the modularity and connectivity of the human brain  

Microsoft Academic Search

The brain is organized around two complementary principles: modularity and connectivity. This PhD thesis introduces and evaluates novel methods to study both principles in the human brain in vivo. These methods are based on functional Magnetic Resonance Imaging (MRI), which is sensitive to the activation of brain regions and on diffusion MRI, which is sensitive to the structure of the

H. M. J. Fonteijn

2012-01-01

405

A Celebration of Neurons: An Educator's Guide to the Human Brain.  

ERIC Educational Resources Information Center

|This book provides an introduction to the current scientific understanding of the human brain and its processes. Chapter 1, "At the Edge of a Major Transformation," is an introduction to the field. Chapter 2, "How Our Brain Organizes Itself on the Cellular and Systems Levels," covers what body/brain cellular systems do, how cells process units of…

Sylwester, Robert

406

Evolution of human brain functions: the functional structure of human consciousness.  

PubMed

The functional structure of self-aware consciousness in human beings is described based on the evolution of human brain functions. Prior work on heritable temperament and character traits is extended to account for the quantum-like and holographic properties (i.e. parts elicit wholes) of self-aware consciousness. Cladistic analysis is used to identify the succession of ancestors leading to human beings. The functional capacities that emerge along this lineage of ancestors are described. The ecological context in which each cladogenesis occurred is described to illustrate the shifting balance of evolution as a complex adaptive system. Comparative neuroanatomy is reviewed to identify the brain structures and networks that emerged coincident with the emergent brain functions. Individual differences in human temperament traits were well developed in the common ancestor shared by reptiles and humans. Neocortical development in mammals proceeded in five major transitions: from early reptiles to early mammals, early primates, simians, early Homo, and modern Homo sapiens. These transitions provide the foundation for human self-awareness related to sexuality, materiality, emotionality, intellectuality, and spirituality, respectively. The functional structure of human self-aware consciousness is concerned with the regulation of five planes of being: sexuality, materiality, emotionality, intellectuality, and spirituality. Each plane elaborates neocortical functions organized around one of the five special senses. The interactions among these five planes gives rise to a 5 x 5 matrix of subplanes, which are functions that coarsely describe the focus of neocortical regulation. Each of these 25 neocortical functions regulates each of five basic motives or drives that can be measured as temperaments or basic emotions related to fear, anger, disgust, surprise, and happiness/sadness. The resulting 5 x 5 x 5 matrix of human characteristics provides a general and testable model of the functional structure of human consciousness that includes personality, physicality, emotionality, cognition, and spirituality in a unified developmental framework. PMID:20001395

Cloninger, C Robert

2009-11-01

407

Beyond the visible--imaging the human brain with light.  

PubMed

Optical approaches to investigate cerebral function and metabolism have long been applied in invasive studies. From the neuron cultured to the exposed cortex in the human during neurosurgical procedures, high spatial resolution can be reached and several processes such as membrane potential, cell swelling, metabolism of mitochondrial chromophores, and vascular response can be monitored, depending on the respective preparation. The authors focus on an extension of optical methods to the noninvasive application in the human. Starting with the pioneering work of Jöbsis 25 years ago, near-infrared spectroscopy (NIRS) has been used to investigate functional activation of the human cerebral cortex. Recently, several groups have started to use imaging systems that allow the generation of images of a larger area of the subject's head and, thereby, the production of maps of cortical oxygenation changes. Such images have a much lower spatial resolution compared with the invasively obtained optical images. The noninvasive NIRS images, however, can be obtained in undemanding set-ups that can be easily combined with other functional methods, in particular EEG. Moreover, NIRS is applicable to bedside use. The authors briefly review some of the abundant literature on intrinsic optical signals and the NIRS imaging studies of the past few years. The weaknesses and strengths of the approach are critically discussed. The authors conclude that NIRS imaging has two major advantages: it can address issues concerning neurovascular coupling in the human adult and can extend functional imaging approaches to the investigation of the diseased brain. PMID:12500086

Obrig, Hellmuth; Villringer, Arno

2003-01-01

408

Deep Brain Stimulation, Brain Maps and Personalized Medicine: Lessons from the Human Genome Project.  

PubMed

Although the appellation of personalized medicine is generally attributed to advanced therapeutics in molecular medicine, deep brain stimulation (DBS) can also be so categorized. Like its medical counterpart, DBS is a highly personalized intervention that needs to be tailored to a patient's individual anatomy. And because of this, DBS like more conventional personalized medicine, can be highly specific where the object of care is an N = 1. But that is where the similarities end. Besides their differing medical and surgical provenances, these two varieties of personalized medicine have had strikingly different impacts. The molecular variant, though of a more recent vintage has thrived and is experiencing explosive growth, while DBS still struggles to find a sustainable therapeutic niche. Despite its promise, and success as a vetted treatment for drug resistant Parkinson's Disease, DBS has lagged in broadening its development, often encountering regulatory hurdles and financial barriers necessary to mount an adequate number of quality trials. In this paper we will consider why DBS-or better yet neuromodulation-has encountered these challenges and contrast this experience with the more successful advance of personalized medicine. We will suggest that personalized medicine and DBS's differential performance can be explained as a matter of timing and complexity. We believe that DBS has struggled because it has been a journey of scientific exploration conducted without a map. In contrast to molecular personalized medicine which followed the mapping of the human genome and the Human Genome Project, DBS preceded plans for the mapping of the human brain. We believe that this sequence has given personalized medicine a distinct advantage and that the fullest potential of DBS will be realized both as a cartographical or electrophysiological probe and as a modality of personalized medicine. PMID:23749308

Fins, Joseph J; Shapiro, Zachary E

2013-06-01

409

The remarkable, yet not extraordinary, human brain as a scaled-up primate brain and its associated cost.  

PubMed

Neuroscientists have become used to a number of "facts" about the human brain: It has 100 billion neurons and 10- to 50-fold more glial cells; it is the largest-than-expected for its body among primates and mammals in general, and therefore the most cognitively able; it consumes an outstanding 20% of the total body energy budget despite representing only 2% of body mass because of an increased metabolic need of its neurons; and it is endowed with an overdeveloped cerebral cortex, the largest compared with brain size. These facts led to the widespread notion that the human brain is literally extraordinary: an outlier among mammalian brains, defying evolutionary rules that apply to other species, with a uniqueness seemingly necessary to justify the superior cognitive abilities of humans over mammals with even larger brains. These facts, with deep implications for neurophysiology and evolutionary biology, are not grounded on solid evidence or sound assumptions, however. Our recent development of a method that allows rapid and reliable quantification of the numbers of cells that compose the whole brain has provided a means to verify these facts. Here, I review this recent evidence and argue that, with 86 billion neurons and just as many nonneuronal cells, the human brain is a scaled-up primate brain in its cellular composition and metabolic cost, with a relatively enlarged cerebral cortex that does not have a relatively larger number of brain neurons yet is remarkable in its cognitive abilities and metabolism simply because of its extremely large number of neurons. PMID:22723358

Herculano-Houzel, Suzana

2012-06-20

410

Gorilla and orangutan brains conform to the primate cellular scaling rules: implications for human evolution.  

PubMed

Gorillas and orangutans are primates at least as large as humans, but their brains amount to about one third of the size of the human brain. This discrepancy has been used as evidence that the human brain is about 3 times larger than it should be for a primate species of its body size. In contrast to the view that the human brain is special in its size, we have suggested that it is the great apes that might have evolved bodies that are unusually large, on the basis of our recent finding that the cellular composition of the human brain matches that expected for a primate brain of its size, making the human brain a linearly scaled-up primate brain in its number of cells. To investigate whether the brain of great apes also conforms to the primate cellular scaling rules identified previously, we determine the numbers of neuronal and other cells that compose the orangutan and gorilla cerebella, use these numbers to calculate the size of the brain and of the cerebral cortex expected for these species, and show that these match the sizes described in the literature. Our results suggest that the brains of great apes also scale linearly in their numbers of neurons like other primate brains, including humans. The conformity of great apes and humans to the linear cellular scaling rules that apply to other primates that diverged earlier in primate evolution indicates that prehistoric Homo species as well as other hominins must have had brains that conformed to the same scaling rules, irrespective of their body size. We then used those scaling rules and published estimated brain volumes for various hominin species to predict the numbers of neurons that composed their brains. We predict that Homo heidelbergensis and Homo neanderthalensis had brains with approximately 80 billion neurons, within the range of variation found in modern Homo sapiens. We propose that while the cellular scaling rules that apply to the primate brain have remained stable in hominin evolution (since they apply to simians, great apes and modern humans alike), the Colobinae and Pongidae lineages favored marked increases in body size rather than brain size from the common ancestor with the Homo lineage, while the Homo lineage seems to have favored a large brain instead of a large body, possibly due to the metabolic limitations to having both. PMID:21228547

Herculano-Houzel, Suzana; Kaas, Jon H

2011-01-11

411

Gorilla and Orangutan Brains Conform to the Primate Cellular Scaling Rules: Implications for Human Evolution  

PubMed Central

Gorillas and orangutans are primates at least as large as humans, but their brains amount to about one third of the size of the human brain. This discrepancy has been used as evidence that the human brain is about 3 times larger than it should be for a primate species of its body size. In contrast to the view that the human brain is special in its size, we have suggested that it is the great apes that might have evolved bodies that are unusually large, on the basis of our recent finding that the cellular composition of the human brain matches that expected for a primate brain of its size, making the human brain a linearly scaled-up primate brain in its number of cells. To investigate whether the brain of great apes also conforms to the primate cellular scaling rules identified previously, we determine the numbers of neuronal and other cells that compose the orangutan and gorilla cerebella, use these numbers to calculate the size of the brain and of the cerebral cortex expected for these species, and show that these match the sizes described in the literature. Our results suggest that the brains of great apes also scale linearly in their numbers of neurons like other primate brains, including humans. The conformity of great apes and humans to the linear cellular scaling rules that apply to other primates that diverged earlier in primate evolution indicates that prehistoric Homo species as well as other hominins must have had brains that conformed to the same scaling rules, irrespective of their body size. We then used those scaling rules and published estimated brain volumes for various hominin species to predict the numbers of neurons that composed their brains. We predict that Homo heidelbergensis and Homo neanderthalensis had brains with approximately 80 billion neurons, within the range of variation found in modern Homo sapiens. We propose that while the cellular scaling rules that apply to the primate brain have remained stable in hominin evolution (since they apply to simians, great apes and modern humans alike), the Colobinae and Pongidae lineages favored marked increases in body size rather than brain size from the common ancestor with the Homo lineage, while the Homo lineage seems to have favored a large brain instead of a large body, possibly due to the metabolic limitations to having both.

Herculano-Houzel, Suzana; Kaas, Jon H.

2011-01-01

412

A unique case of naturally occurring mummification of human brain tissue.  

PubMed

When skulls and bones were exhumed from a mass grave in Bulgaria and subjected to medicolegal examination they were found to originate from 39 humans aged 36-60 years old who had been buried approximately 45-50 years ago. Solid structures which strongly resembled shrunken human brain tissue were found inside 2 intact skulls. Among other bones 5 similar structures were found one of which was an almost entirely preserved human brain, and the others were fragments from different regions of the human brain. Samples of these structures were immersed in 15% aqueous glycerol solution to soften and were examined by light and electron microscopy. Samples of this material and of fresh human brain were subjected to elementary atomic spectral analysis. These complex studies indicated the samples to be naturally mummified human brain tissue and that this process had occurred due to specific conditions within the cranial cavities after burial. PMID:1419879

Radanov, S; Stoev, S; Davidov, M; Nachev, S; Stanchev, N; Kirova, E

1992-01-01

413

Mona Lisa smile: the morphological enigma of human and great ape evolution.  

PubMed

The science of human evolution is confronted with the popular chimpanzee theory and the earlier but largely ignored orangutan theory. The quality and scope of published documentation and verification of morphological features suggests there is very little in morphology to support a unique common ancestor for humans and chimpanzees. A close relationship between humans and African apes is currently supported by only eight unproblematic characters. The orangutan relationship is supported by about 28 well-supported characters, and it is also corroborated by the presence of orangutan-related features in early hominids. The uniquely shared morphology of humans and orangutans raises doubts about the almost universal belief that DNA sequence similarities necessarily demonstrate a closer evolutionary relationship between humans and chimpanzees. A new evolutionary reconstruction is proposed for the soft tissue anatomy, physiology, and behavioral biology of the first hominids that includes concealed ovulation, male beard and mustache, prolonged mating, extended pair-bonding, "house" construction, mechanical "genius," and artistic expression. PMID:16865704

Grehan, John R

2006-07-01

414

Morphological findings in the brain after experimental gunshots using radiology, pathology and histology  

Microsoft Academic Search

The tissue disruption inside the brain after experimental gunshots to the head was investigated with special reference to\\u000a secondary bone missiles and intracranial pressure effects such as cortical contusion and deep intracerebral haemorrhages.\\u000a The evidential value of various examination methods is compared. 9 mm Parabellum ammunition was fired to the temporal region\\u000a of calves (n = 10) from a distance

B. Karger; Z. Puskas; B. Ruwald; K. Teige; G. Schuirer

1998-01-01

415

The p53 gene and protein in human brain tumors  

SciTech Connect

Because p53 gene alterations are commonplace in human tumors and because p53 protein is involved in a number of important cellular pathways, p53 has become a topic of intensive investigation, both by basic scientists and clinicians. p53 was initially identified by two independent laboratories in 1979 as a 53 kilodalton (kD) protein that complexes with the large T antigen of SV40 virus. Shortly thereafter, it was shown that the E1B oncoprotein of adenovirus also binds p53. The binding of two different oncogenic viral tumor proteins to the same cellular protein suggested that p53 might be integral to tumorigenesis. The human p53 cDNA and gene were subsequently cloned in the mid-1980s, and analysis of p53 gene alterations in human tumors followed a few year later. During these 10 years, researchers grappling with the vagaries of p53 first characterized the gene as an oncogene, then as a tumor suppressor gene, and most recently as both a tumor suppressor gene and a so-called [open quotes]dominant negative[close quotes] oncogene. The last few years have seen an explosion in work on this single gene and its protein product. A review of a computerized medical database revealed approximately 650 articles on p53 in 1992 alone. p53 has assumed importance in neuro-oncology because p53 mutations and protein alterations are frequent in the common diffuse, fibrillary astrocytic tumors of adults. p53 mutations in astrocytomas were first described in 1989 and were followed by more extensive analyses of gene mutations and protein alterations in adult astrocytomas. The gene has also been studied in less common brain tumors. Elucidating the role of p53 in brain tumorigenesis will not only enhance understanding of brain tumor biology but may also contribute to improved diagnosis and therapy. This discussion reviews key aspects of the p53 gene and protein, and describe their emerging roles in central nervous system neoplasia. 102 refs., 6 figs., 1 tab.

Louis, D.N. (Massachusetts General Hospital, Boston, MA (United States))

1994-01-01

416

Selectivity to translational egomotion in human brain motion areas.  

PubMed

The optic flow generated when a person moves through the environment can be locally decomposed into several basic components, including radial, circular, translational and spiral motion. Since their analysis plays an important part in the visual perception and control of locomotion and posture it is likely that some brain regions in the primate dorsal visual pathway are specialized to distinguish among them. The aim of this study is to explore the sensitivity to different types of egomotion-compatible visual stimulations in the human motion-sensitive regions of the brain. Event-related fMRI experiments, 3D motion and wide-field stimulation, functional localizers and brain mapping methods were used to study the sensitivity of six distinct motion areas (V6, MT, MST+, V3A, CSv and an Intra-Parietal Sulcus motion [IPSmot] region) to different types of optic flow stimuli. Results show that only areas V6, MST+ and IPSmot are specialized in distinguishing among the various types of flow patterns, with a high response for the translational flow which was maximum in V6 and IPSmot and less marked in MST+. Given that during egomotion the translational optic flow conveys differential information about the near and far external objects, areas V6 and IPSmot likely process visual egomotion signals to extract information about the relative distance of objects with respect to the observer. Since area V6 is also involved in distinguishing object-motion from self-motion, it could provide information about location in space of moving and static objects during self-motion, particularly in a dynamically unstable environment. PMID:23577096

Pitzalis, Sabrina; Sdoia, Stefano; Bultrini, Alessandro; Committeri, Giorgia; Di Russo, Francesco; Fattori, Patrizia; Galletti, Claudio; Galati, Gaspare

2013-04-05

417

Variation in human brains may facilitate evolutionary change toward a limited range of phenotypes.  

PubMed

Individual variation is the foundation for evolutionary change, but little is known about the nature of normal variation between brains. Phylogenetic variation across mammalian brains is characterized by high intercorrelations in brain region volumes, distinct allometric scaling for each brain region and the relative independence of olfactory and limbic structure volumes from the rest of the brain. Previous work examining brain variation in individuals of some domesticated species showed that these three features of phylogenetic variation were mirrored in individual variation. We extend this analysis to the human brain and 10 of its subdivisions (e.g., isocortex and hippocampus) by using magnetic resonance imaging scans of 90 human brains ranging between 16 and 25 years of age. Human brain variation resembles both the individual variation seen in other species and variation observed across mammalian species, i.e., the relative differences in the slopes of each brain region compared to medulla size within humans and between mammals are concordant, and limbic structures scale with relative independence from other brain regions. This nonrandom pattern of variation suggests that developmental programs channel the variation available for selection. PMID:23363667

Charvet, Christine J; Darlington, Richard B; Finlay, Barbara L

2013-01-25

418

Neuroactive amino acids in focally epileptic human brain: a review.  

PubMed

Studies of neuroactive amino acids and their regulatory enzymes in surgically excised focally epileptic human brain are reviewed. Concentrations of glutamate, aspartate and glycine are significantly increased in epileptogenic cerebral cortex. The activities of the enzymes, glutamate dehydrogenase and aspartate aminotransferase, involved in glutamate and aspartate metabolism are also increased. Polyamine synthesis is enhanced in epileptogenic cortex and may contribute to the activation of N-methyl-D-aspartate (NMDA) receptors. Nuclear magnetic resonance spectroscopy (NMRS) reveals that patients with poorly controlled complex partial seizures have a significant diminution in occipital lobe gamma aminobutyric acid (GABA) concentration. The activity of the enzyme GABA-aminotransaminase (GABA-T) which catalyzes GABA degradation is not altered in epileptogenic cortex. NMRS studies show that vigabatrin, a GABA-T inhibitor and effective antiepileptic, significantly increases brain GABA. Glutamate decarboxylase (GAD), responsible for GABA synthesis, is diminished in interneurons in discrete regions of epileptogenic cortex and hippocampus. In vivo microdialysis performed in epilepsy surgery patients provides measurements of extracellular amino acid levels during spontaneous seizures. Glutamate concentrations are higher in epileptic hippocampi