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Sample records for absent corpus callosum

  1. Bilingual Corpus Callosum Variability

    ERIC Educational Resources Information Center

    Coggins, Porter E., III.; Kennedy, Teresa J.; Armstrong, Terry A.

    2004-01-01

    Magnetic resonance imaging was used to produce midsagittal images of the corpus callosum of 19 right-handed adult male and female subjects. The preliminary findings of this study indicate that significant adaptation in the anterior midbody of the corpus callosum has occurred to accommodate multiple language capacity in bilingual individuals…

  2. Oculomotor-corpus callosum dysplasia.

    PubMed

    Acers, T E; Blackwell, C

    1982-01-01

    An infant with congenital bilateral ophthalmoplegia with levator and pupillary sparing is presented. The eyes are fixed in a divergent position with no apparent motility. The baby is otherwise clinically normal and is developing in a normal fashion except for delayed growth pattern. Visual attention is present and he fixates with either eye. Computed tomography demonstrates an associated dysplasia of the corpus callosum and an abnormal ventricular system. Neuroendocrine studies performed at one year of age demonstrate subnormal levels of growth hormone. It is postulated that this represents an embryodysgenesis involving the developing mesencephalic tegmentum (oculomotor nuclei) and the diencephalic lamina reuniens (corpus callosum). It is the first reported case of congenital ophthalmoplegia with corpus callosum dysplasia. The "embryodysgenic" relationship with other forebrain-ocular anomalies has been alluded to and remains speculative. PMID:7182958

  3. Corpus Callosum Volume and Neurocognition in Autism

    ERIC Educational Resources Information Center

    Keary, Christopher J.; Minshew, Nancy J.; Bansal, Rahul; Goradia, Dhruman; Fedorov, Serguei; Keshavan, Matcheri S.; Hardan, Antonio Y.

    2009-01-01

    The corpus callosum has recently been considered as an index of interhemispheric connectivity. This study applied a novel volumetric method to examine the size of the corpus callosum in 32 individuals with autism and 34 age-, gender- and IQ-matched controls and to investigate the relationship between this structure and cognitive measures linked to…

  4. Corpus Callosum Area in Children and Adults with Autism

    ERIC Educational Resources Information Center

    Prigge, Molly B. D.; Lange, Nicholas; Bigler, Erin D.; Merkley, Tricia L.; Neeley, E. Shannon; Abildskov, Tracy J.; Froehlich, Alyson L.; Nielsen, Jared A.; Cooperrider, Jason R.; Cariello, Annahir N.; Ravichandran, Caitlin; Alexander, Andrew L.; Lainhart, Janet E.

    2013-01-01

    Despite repeated findings of abnormal corpus callosum structure in autism, the developmental trajectories of corpus callosum growth in the disorder have not yet been reported. In this study, we examined corpus callosum size from a developmental perspective across a 30-year age range in a large cross-sectional sample of individuals with autism…

  5. Corpus callosum: microsurgical anatomy and MRI.

    PubMed

    Gonçalves-Ferreira, A J; Herculano-Carvalho, M; Melancia, J P; Farias, J P; Gomes, L

    2001-01-01

    The anatomy of the corpus callosum has received renewed interest during recent years due to the increasing number of callosotomies performed to treat intraventricular lesions, as well as some forms of generalized epilepsy. We have previously reported on the microsurgical anatomy of the corpus callosum and identified specific anatomical reference landmarks that can be used during surgery. In the present study we have continued the anatomical aspect of this earlier work in a larger number of cases, with in vitro observations (brain out of skull) being compared with the corresponding in vivo features seen in sagittal MRI slices. Fifty-three in vitro microsurgical callosotomies was performed and the data collected compared with a series of 57 in vivo normal MR callosal images. Callosal dimensions were measured on both the anatomical and MRI material, thus overcoming the problems associated with in vitro callosal deformation. Of the anatomical landmarks studied the distance from the genu of the corpus callosum to the bifurcation of the columns of the fornix was found to be useful for the intraoperative evaluation of the extent of rostral callosotomy, as it is not significantly changed in in vitro. The main microsurgical features of rostral callosotomy are presented. PMID:11963623

  6. Infarction of the Corpus Callosum: A Retrospective Clinical Investigation

    PubMed Central

    Bai, Yu-meng; Qin, Hua-min; Wu, Xiao-mei; Zhang, Xiao; Jolkkonen, Jukka; Boltze, Johannes; Wang, Su-ping

    2015-01-01

    Objectives The aim of this study was to investigate patients with ischemic infarctions in the territory of the corpus callosum to advance our understanding of this rare stroke subtype by providing comprehensive descriptive and epidemiological data. Methods From January 1, 2010 to June 30, 2014, all cases of acute ischemic stroke diagnosed by clinical manifestation and diffusion weighted imaging in Dalian Municipal Central Hospital were investigated. The patients presenting with corpus callosum infarctions were selected and further allocated into genu and/or body and splenium infarction groups. Proportion, lesion patterns, clinical features, risk factors and etiology of corpus callosum infarction were analyzed. Results Out of 1,629 cases, 59 patients (3.6%) with corpus callosum infarctions were identified by diffusion weighted imaging, including 7 patients who had ischemic lesions restricted to the corpus callosum territory. Thirty six patients had lesions in the splenium (61.0%). Corpus callosum infarction patients suffered from a broad spectrum of symptoms including weakness and/or numbness of the limbs, clumsy speech, and vertigo, which could not be explained by lesions in corpus callosum. A classical callosal disconnection syndrome was found in 2 out of all patients with corpus callosum infarctions. Statistical differences in the risk factor and infarct pattern between the genu and/or body group and splenium group were revealed. Conclusion Corpus callosum infarction and the callosal disconnection syndrome were generally rare. The most susceptible location of ischemic corpus callosum lesion was the splenium. Splenium infarctions were often associated with bilateral cerebral hemisphere involvement (46.2%). The genu and/or body infarctions were associated with atherosclerosis. The most common cause of corpus callosum infarction probably was embolism. PMID:25785450

  7. Corpus Callosum Morphometrics in Young Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Boger-Megiddo, Inbal; Shaw, Dennis W. W.; Friedman, Seth D.; Sparks, Bobbi F.; Artru, Alan A.; Giedd, Jay N.; Dawson, Geraldine; Dager, Stephen R.

    2006-01-01

    This study assessed digital corpus callosum cross sectional areas in 3-4 year olds with autism spectrum disorder (ASD) compared to typically developing (TD) and developmentally delayed (DD) children. Though not different in absolute size compared to TD, ASD callosums were disproportionately small adjusted for increased ASD cerebral volume. ASD…

  8. Pituitary duplication associated with oral dermoid and corpus callosum hypogenesis.

    PubMed

    Mutlu, Hakan; Paker, Bilhan; Gunes, Nilufer; Emektar, Ali; Keceli, Merter; Kantarci, Mecit

    2004-12-01

    We report a case of pituitary duplication in a neonate girl whose magnetic resonance (MR) images showed unusual findings of hypogenesis of the corpus callosum and oral dermoid. Pituitary duplication is an extremely rare malformation, with only a few previously reported cases. It occurs most commonly in association with complicated midline and skull base anomalies. We present a case of this malformation with special emphasis on the hypogenesis of splenium of the corpus callosum and oral dermoid. PMID:15565346

  9. Corpus Callosum Area in Children and Adults with Autism

    PubMed Central

    Prigge, Molly B. D.; Lange, Nicholas; Bigler, Erin D.; Merkley, Tricia L.; Neeley, E. Shannon; Abildskov, Tracy J.; Froehlich, Alyson L.; Nielsen, Jared A.; Cooperrider, Jason R.; Cariello, Annahir N.; Ravichandran, Caitlin; Alexander, Andrew L.; Lainhart, Janet E.

    2012-01-01

    Despite repeated findings of abnormal corpus callosum structure in autism, the developmental trajectories of corpus callosum growth in the disorder have not yet been reported. In this study, we examined corpus callosum size from a developmental perspective across a 30-year age range in a large cross-sectional sample of individuals with autism compared to a typically developing sample. Midsagittal corpus callosum area and the 7 Witelson subregions were examined in 68 males with autism (mean age 14.1 years; range 3–36 years) and 47 males with typical development (mean age 15.3 years; range 4–29 years). Controlling for total brain volume, increased variability in total corpus callosum area was found in autism. In autism, increased midsagittal areas were associated with reduced severity of autism behaviors, higher intelligence, and faster speed of processing (p=0.003, p=0.011, p=0.013, respectively). A trend toward group differences in isthmus development was found (p=0.029, uncorrected). These results suggest that individuals with autism benefit functionally from increased corpus callosum area. Our cross-sectional examination also shows potential maturational abnormalities in autism, a finding that should be examined further with longitudinal datasets. PMID:23130086

  10. Neuronal fiber composition of the corpus callosum within some odontocetes.

    PubMed

    Keogh, Mandy J; Ridgway, Sam H

    2008-07-01

    Odontocetes (toothed whales) evolved from terrestrial mammals approximately 55 million years ago and have since remained on a unique evolutionary trajectory. This study used formalin-fixed tissue and light microscopy to quantify the size and number of fibers along the corpus callosum of the bottlenose dolphin (n = 8). Two other species, the Amazon River dolphin (n = 1) and the killer whale (n = 1), were included for comparison. A large amount of variation in the shape and area of the corpus callosum was observed. The odontocete corpus callosum is a heterogeneous structure with variation in fiber size and density along the length of the corpus callosum in all specimens examined. Using the species with the largest sample size, the bottlenose dolphin, comparisons by sex and age (sexually mature verses immature) were made for the area of the corpus callosum, five subregions, and fiber densities. Although no sex differences were detected, age appeared to affect the size, shape, and fiber composition of the bottlenose dolphin corpus callosum. PMID:18493931

  11. Interleukin-6, Age, and Corpus Callosum Integrity

    PubMed Central

    Bettcher, Brianne M.; Watson, Christa L.; Walsh, Christine M.; Lobach, Iryna V.; Neuhaus, John; Miller, Joshua W.; Green, Ralph; Patel, Nihar; Dutt, Shubir; Busovaca, Edgar; Rosen, Howard J.; Yaffe, Kristine; Miller, Bruce L.; Kramer, Joel H.

    2014-01-01

    The contribution of inflammation to deleterious aging outcomes is increasingly recognized; however, little is known about the complex relationship between interleukin-6 (IL-6) and brain structure, or how this association might change with increasing age. We examined the association between IL-6, white matter integrity, and cognition in 151 community dwelling older adults, and tested whether age moderated these associations. Blood levels of IL-6 and vascular risk (e.g., homocysteine), as well as health history information, were collected. Processing speed assessments were administered to assess cognitive functioning, and we employed tract-based spatial statistics to examine whole brain white matter and regions of interest. Given the association between inflammation, vascular risk, and corpus callosum (CC) integrity, fractional anisotropy (FA) of the genu, body, and splenium represented our primary dependent variables. Whole brain analysis revealed an inverse association between IL-6 and CC fractional anisotropy. Subsequent ROI linear regression and ridge regression analyses indicated that the magnitude of this effect increased with age; thus, older individuals with higher IL-6 levels displayed lower white matter integrity. Finally, higher IL-6 levels were related to worse processing speed; this association was moderated by age, and was not fully accounted for by CC volume. This study highlights that at older ages, the association between higher IL-6 levels and lower white matter integrity is more pronounced; furthermore, it underscores the important, albeit burgeoning role of inflammatory processes in cognitive aging trajectories. PMID:25188448

  12. Corpus Callosum Volume in Children with Autism

    PubMed Central

    Hardan, Antonio Y.; Pabalan, Melissa; Gupta, Nidhi; Bansal, Rahul; Melhem, Nadine M.; Fedorov, Serguei; Keshavan, Matcheri S.; Minshew, Nancy J.

    2009-01-01

    The corpus callosum (CC) is the main commissure connecting the cerebral hemispheres. Previous evidence suggests the involvement of CC in the pathophysiology of autism. However, most studies examined the mid-sagittal area and investigations applying more precise methods are warranted. The goal of this investigation is to apply a volumetric method to examine the size of the CC in autism and to identify any association with clinical features. An MRI-based morphometric study of the total CC volume and its 7 subdivisions was conducted and involved 22 children with autism (age range 8.1–12.7 years) and 23 healthy, age-matched controls. Reductions in the total volume of the CC and several of its subdivisions were found in the autism sample. Associations were observed between CC structures and clinical features including social deficits, repetitive behaviors, and sensory abnormalities. Volumetric alterations of the CC observed in this investigation are consistent with midsagittal area tracings of decreased CC size in autism. These findings support the aberrant connectivity hypothesis with possible decrease in interhemispheric communications. PMID:19781917

  13. Corpus callosum volume in children with autism.

    PubMed

    Hardan, Antonio Y; Pabalan, Melissa; Gupta, Nidhi; Bansal, Rahul; Melhem, Nadine M; Fedorov, Serguei; Keshavan, Matcheri S; Minshew, Nancy J

    2009-10-30

    The corpus callosum (CC) is the main commissure connecting the cerebral hemispheres. Previous evidence suggests the involvement of the CC in the pathophysiology of autism. However, most studies examined the mid-sagittal area and investigations applying novel methods are warranted. The goal of this investigation is to apply a volumetric method to examine the size of the CC in autism and to identify any association with clinical features. An MRI-based morphometric study of the total CC volume and its seven subdivisions was conducted and involved 22 children with autism (age range 8.1-12.7 years) and 23 healthy, age-matched controls. Reductions in the total volume of the CC and several of its subdivisions were found in the autism sample. Associations were observed between CC structures and clinical features including social deficits, repetitive behaviors, and sensory abnormalities. Volumetric alterations of the CC observed in this investigation are consistent with midsagittal area tracings of decreased CC size in autism. These findings support the aberrant connectivity hypothesis with possible decrease in interhemispheric communications. PMID:19781917

  14. Corpus callosum in aging and dementia.

    PubMed

    Frederiksen, Kristian Steen

    2013-10-01

    The overarching objective of the thesis was to investigate the morphological changes in the corpus callosum (CC) in aging and dementia in relation to its role in cognitive and motor decline. The CC is the largest white matter tract in the brain, containing upwards of 200 million axons, and is believed important for communication and interaction between the two cerebral hemispheres. Historically, the role of white matter, including the CC, in relation to cognitive function has often been eclipsed by the predominance of the cortex, and led to a "corticocentric" view of the brain and cognitive function. However, from the 1960s and onwards, the role of lesions in the white matter in the appearence of cognitive deficits and diseases such as dementia has become increasingly evident. Many studies have indicated that AD is associated with CC atrophy, but the precise pattern of subregional CC atrophy in different disease stages remains undetermined. In study I, we establish that atrophy is present primarily in the posterior CC early in AD, and that atrophy of the CC is associated with faster disease progression. This finding supports a model where posterior atrophy is the earliest changes in the CC in AD patients, with atrophy of anterior CC being a later pathological event. To further elucidate the role of CC atrophy in dementia, we examined a population of 329 elderly subjects, and found that a higher rate of tissue loss in posterior CC is associated with an increased risk of dementia. This study represents the first to examine CC in elderly subjects longitudinally. In the same cohort, we investigated whether impairment in specific cognitive domains was associated with CC tissue loss. Previous studies had shown that processing speed and executive functions may be particularly reliant on the CC. Our findings indicated that CC tissue loss leads to selective impairment of processing speed but not memory or executive function deficits. Finally, CC tissue loss was also

  15. The Corpus Callosum and Forensic Issues-An Overview.

    PubMed

    Byard, Roger W

    2016-07-01

    The corpus callosum is a large central white matter tract that connects the right and left cerebral hemispheres. It permits placental mammals to have a more sophisticated interhemispheric integration of sensory cortices and allows communication between cortical and subcortical neurons. Search of the literature and the pathology archives at The University of Adelaide was undertaken to identify lesions and injuries within the corpus callosum that may have forensic significance. These include developmental/congenital lesions with agenesis/dysgenesis, vascular malformations, and lipomas; inherited syndromes such as neurofibromatosis; and acquired lesions involving trauma, neoplasia, demyelination, vascular conditions, infections, fat embolism, aging/dementia, and the effects of toxins. The finding of lesions within the corpus callosum should initiate careful examination of the adjacent brain and other organ systems for related phenomena as this may shed some light on the nature of the underlying condition, and also help to determine whether there are any forensic implications. PMID:27364276

  16. Primary human chorionic gonadotropin secreting germinoma of the corpus callosum

    PubMed Central

    Chuan Aaron, Foo Song; Dawn, Chong Q. Q.; Kenneth, Chang T. E.; Hoe, Ng Wai; Yen, Soh Shui; Chee Kian, Tham

    2013-01-01

    Background: Primary intracranial germinomas are a rare subset of intracranial tumors derived from mis-incorporated germ cells within the folding neural plate during embryogenesis. Though known to arise from midline structures in the central nervous system (CNS), occurrence within the corpus callosum is exceedingly rare. Case Description: We present a rare case of secreting primary intracranial germinoma with extensive intraventricular metastasis presenting as a multi-cystic butterfly lesion in the genu of the corpus callosum in a young boy. Conclusion: Intracranial germ cell tumors must be considered for any multi-cystic lesion arising from midline structures in the CNS in the preadult population. PMID:24233184

  17. Corpus Callosum Differences Associated with Persistent Stuttering in Adults

    ERIC Educational Resources Information Center

    Choo, Ai Leen; Kraft, Shelly Jo; Olivero, William; Ambrose, Nicoline G.; Sharma, Harish; Chang, Soo-Eun; Loucks, Torrey M.

    2011-01-01

    Recent studies have implicated anatomical differences in speech-relevant brain regions of adults who stutter (AWS) compared to normally fluent adults (NFA). The present study focused on the region of the corpus callosum (CC) which is involved in interhemispheric processing between the left and right cerebral hemispheres. Two-dimensional…

  18. Perspectives on Dichotic Listening and the Corpus Callosum

    ERIC Educational Resources Information Center

    Musiek, Frank E.; Weihing, Jeffrey

    2011-01-01

    The present review summarizes historic and recent research which has investigated the role of the corpus callosum in dichotic processing within the context of audiology. Examination of performance by certain clinical groups, including split brain patients, multiple sclerosis cases, and other types of neurological lesions is included. Maturational,…

  19. Parenting, corpus callosum, and executive function in preschool children.

    PubMed

    Kok, Rianne; Lucassen, Nicole; Bakermans-Kranenburg, Marian J; van IJzendoorn, Marinus H; Ghassabian, Akhgar; Roza, Sabine J; Govaert, Paul; Jaddoe, Vincent W; Hofman, Albert; Verhulst, Frank C; Tiemeier, Henning

    2014-01-01

    In this longitudinal population-based study (N = 544), we investigated whether early parenting and corpus callosum length predict child executive function abilities at 4 years of age. The length of the corpus callosum in infancy was measured using postnatal cranial ultrasounds at 6 weeks of age. At 3 years, two aspects of parenting were observed: maternal sensitivity during a teaching task and maternal discipline style during a discipline task. Parents rated executive function problems at 4 years of age in five domains of inhibition, shifting, emotional control, working memory, and planning/organizing, using the Behavior Rating Inventory of Executive Function-Preschool Version. Maternal sensitivity predicted less executive function problems at preschool age. A significant interaction was found between corpus callosum length in infancy and maternal use of positive discipline to determine child inhibition problems: The association between a relatively shorter corpus callosum in infancy and child inhibition problems was reduced in children who experienced more positive discipline. Our results point to the buffering potential of positive parenting for children with biological vulnerability. PMID:24028215

  20. Autism Traits in Individuals with Agenesis of the Corpus Callosum

    ERIC Educational Resources Information Center

    Lau, Yolanda C.; Hinkley, Leighton B. N.; Bukshpun, Polina; Strominger, Zoe A.; Wakahiro, Mari L. J.; Baron-Cohen, Simon; Allison, Carrie; Auyeung, Bonnie; Jeremy, Rita J.; Nagarajan, Srikantan S.; Sherr, Elliott H.; Marco, Elysa J.

    2013-01-01

    Autism spectrum disorders (ASD) have numerous etiologies, including structural brain malformations such as agenesis of the corpus callosum (AgCC). We sought to directly measure the occurrence of autism traits in a cohort of individuals with AgCC and to investigate the neural underpinnings of this association. We screened a large AgCC cohort (n =…

  1. Corpus Callosum Anatomy in Chronically Treated and Stimulant Naive ADHD

    ERIC Educational Resources Information Center

    Schnoebelen, Sarah; Semrud-Clikeman, Margaret; Pliszka, Steven R.

    2010-01-01

    Objective: To determine the effect of chronic stimulant treatment on corpus callosum (CC) size in children with ADHD using volumetric and area measurements. Previously published research indicated possible medication effects on specific areas of the CC. Method: Measurements of the CC from anatomical MRIs were obtained from children aged 9-16 in…

  2. Agenesis of the Corpus Callosum Due to Defective Glial Wedge Formation in Lhx2 Mutant Mice.

    PubMed

    Chinn, Gregory A; Hirokawa, Karla E; Chuang, Tony M; Urbina, Cecilia; Patel, Fenil; Fong, Jeanette; Funatsu, Nobuo; Monuki, Edwin S

    2015-09-01

    Establishment of the corpus callosum involves coordination between callosal projection neurons and multiple midline structures, including the glial wedge (GW) rostrally and hippocampal commissure caudally. GW defects have been associated with agenesis of the corpus callosum (ACC). Here we show that conditional Lhx2 inactivation in cortical radial glia using Emx1-Cre or Nestin-Cre drivers results in ACC. The ACC phenotype was characterized by aberrant ventrally projecting callosal axons rather than Probst bundles, and was 100% penetrant on 2 different mouse strain backgrounds. Lhx2 inactivation in postmitotic cortical neurons using Nex-Cre mice did not result in ACC, suggesting that the mutant phenotype was not autonomous to the callosal projection neurons. Instead, ACC was associated with an absent hippocampal commissure and a markedly reduced to absent GW. Expression studies demonstrated strong Lhx2 expression in the normal GW and in its radial glial progenitors, with absence of Lhx2 resulting in normal Emx1 and Sox2 expression, but premature exit from the cell cycle based on EdU-Ki67 double labeling. These studies define essential roles for Lhx2 in GW, hippocampal commissure, and corpus callosum formation, and suggest that defects in radial GW progenitors can give rise to ACC. PMID:24781987

  3. Anterior commissure versus corpus callosum: A quantitative comparison across mammals.

    PubMed

    Ashwell, Ken W S

    2016-04-01

    Mammals rely on two major pathways to transfer information between the two hemispheres of the brain: the anterior commissure and the corpus callosum. Metatheria and monotremes rely exclusively on the anterior commissure for interhemispheric transfer between the isocortices and olfactory allocortices of each side, whereas Eutheria use a combination of the anterior commissure and an additional pathway exclusive to Eutheria, the corpus callosum. Midline cross-sectional area of the anterior commissure and corpus callosum were measured in a range of mammals from all three infraclasses and plotted against brain volume to determine how midline anterior commissure area and its size relative to the corpus callosum vary with brain size and taxon. In Metatheria, the square root of anterior commissure area rises in almost direct proportion with the cube root of brain volume (i.e. the ratio of the two is relatively constant), whereas among Eutheria the ratio of the square root of anterior commissure area to the cube root of brain volume declines slightly with increasing brain size. The total of isocortical and olfactory allocortical commissure area rises more rapidly with increasing brain volume among Eutheria than among Metatheria. This means that the midline isocortical and olfactory allocortical commissural area of metatherians with large brains (about 70 ml) is only about 50% of that among eutherians with similarly sized brains. On the other hand, isocortical and olfactory allocortical commissural area is similar in Metatheria and Eutheria at brain volumes around 1 ml. Among the Eutheria, some groups make less use of the anterior commissure pathway than do others: soricomorphs, rodents and cetaceans have smaller anterior commissures for their brain size than do afrosoricids, erinaceomorphs and proboscideans. The findings suggest that use of the anterior commissural route for isocortical commissural connections may have placed limitations on interhemispheric transfer of

  4. Difference between smokers and non-smokers in the corpus callosum volume.

    PubMed

    Choi, Mi-Hyun; Lee, Su-Jeong; Yang, Jae-Woong; Kim, Ji-Hye; Choi, Jin-Seung; Park, Jang-Yeon; Jun, Jae-Hoon; Tack, Gye-Rae; Lee, Beob-Yi; Kim, Hyun-Jun; Chung, Soon-Cheol

    2010-11-12

    The purpose of this study was to analyze the effects of smoking on corpus callosum volume. In addition, the relationships between smoking duration, smoking frequency, and corpus callosum volume were analyzed. Magnetic resonance brain images were acquired for 58 normal Korean men (30 smokers (age 32.82±14.12 years) and 28 non-smokers (age 35.49±13.11 years)). The corpus callosum volume was measured using Brain Voyager 2000S/W and was normalized by intracranical volume, which was calculated using cerebral sizes. The corpus callosum volume for smokers was significantly smaller than that for non-smokers. Also, there was a negative correlation between corpus callosum volume and smoking duration. The change of white matter volume (e.g., corpus callosum) might be a primary factor for characterizing the effects of smoking. PMID:20804817

  5. [A case of spastic paraparesis with mental deterioration and markedly thin corpus callosum--callosal dysfunction demonstrated by magnetic stimulation].

    PubMed

    Katayama, T; Sakamoto, N; Kuroda, K; Yahara, O; Ugawa, Y

    1998-05-01

    We have studied function of the corpus callosum in a patient with spastic paraparesis with mental deterioration and markedly thin corpus callosum using magnetic stimulation methods. In a 21-year-old woman with slowly progressive gait disturbance, neurological examination showed mental deterioration, euphoria, spastic paraparesis, bilateral Babinski's sign, and hyperesthesia caudal to the eighth thoracic level. No abnormalities were observed in electroencephalograms. Magnetic resonance imaging (MRI) studies of the brain showed cerebral cortical atrophy, markedly thin corpus callosum, and dilated cavum septum pellucidum and cavum Vergae, but spinal cord MRIs showed no abnormalities. The lysosomal enzyme activities, whose reduction was known to cause leukodystrophy, were all normal. Very long chain fatty acid was not increased in her blood, which is against adrenoleukodystrophy. She had no anti-HTLV-1 virus antibody. Based on these clinical features and the results of biochemical analyses, we diagnosed this patient as having spastic paraplegia associated with hypoplasia of the corpus callosum (Nojima and Iwabuchi). We performed three studies on the central motor pathways in this patient. The latencies of responses recorded from upper or lower limb muscles were all within the normal range, despite that the thresholds were slightly increased. This suggests that axonal degeneration occurs in the central motor pathways, which is consistent with the autopsy findings of a patient with hereditary spastic paraplegia associated with hypoplasia of the corpus callosum. Connection between the bilateral motor cortices was investigated by magnetic stimulation of both motor cortices. The suppression of the motor cortex evoked by stimulation of the contralateral motor cortex through the corpus callosum was absent in this patient. Intracortical inhibition within the motor cortex was demonstrated to be normal by a paired-magnetic stimulation technique. Based on the results of these

  6. Facial emotion recognition in agenesis of the corpus callosum

    PubMed Central

    2014-01-01

    Background Impaired social functioning is a common symptom of individuals with developmental disruptions in callosal connectivity. Among these developmental conditions, agenesis of the corpus callosum provides the most extreme and clearly identifiable example of callosal disconnection. To date, deficits in nonliteral language comprehension, humor, theory of mind, and social reasoning have been documented in agenesis of the corpus callosum. Here, we examined a basic social ability as yet not investigated in this population: recognition of facial emotion and its association with social gaze. Methods Nine individuals with callosal agenesis and nine matched controls completed four tasks involving emotional faces: emotion recognition from upright and inverted faces, gender recognition, and passive viewing. Eye-tracking data were collected concurrently on all four tasks and analyzed according to designated facial regions of interest. Results Individuals with callosal agenesis exhibited impairments in recognizing emotions from upright faces, in particular lower accuracy for fear and anger, and these impairments were directly associated with diminished attention to the eye region. The callosal agenesis group exhibited greater consistency in emotion recognition across conditions (upright vs. inverted), with poorest performance for fear identification in both conditions. The callosal agenesis group also had atypical facial scanning (lower fractional dwell time in the eye region) during gender naming and passive viewing of faces, but they did not differ from controls on gender naming performance. The pattern of results did not differ when taking into account full-scale intelligence quotient or presence of autism spectrum symptoms. Conclusions Agenesis of the corpus callosum results in a pattern of atypical facial scanning characterized by diminished attention to the eyes. This pattern suggests that reduced callosal connectivity may contribute to the development and

  7. Verbal learning and memory in agenesis of the corpus callosum.

    PubMed

    Erickson, Roger L; Paul, Lynn K; Brown, Warren S

    2014-07-01

    The role of interhemispheric interactions in the encoding, retention, and retrieval of verbal memory can be clarified by assessing individuals with complete or partial agenesis of the corpus callosum (AgCC), but who have normal intelligence. This study assessed verbal learning and memory in AgCC using the California Verbal Learning Test-Second Edition (CVLT-II). Twenty-six individuals with AgCC were compared to 24 matched controls on CVLT-II measures, as well as Donders׳ four CVLT-II factors (i.e., Attention Span, Learning Efficiency, Delayed Memory, and Inaccurate Memory). Individuals with AgCC performed significantly below healthy controls on the Delayed Memory factor, confirmed by significant deficits in short and long delayed free recall and cued recall. They also performed less well in original learning. Deficient performance by individuals with AgCC during learning trials, as well as deficits in all forms of delayed memory, suggest that the corpus callosum facilitates interhemispheric elaboration and encoding of verbal information. PMID:24933663

  8. Corpus Callosum and Prefrontal Functions in Adolescents with History of Very Preterm Birth

    ERIC Educational Resources Information Center

    Narberhaus, Ana; Segarra, Dolors; Caldu, Xavier; Gimenez, Monica; Pueyo, Roser; Botet, Francesc; Junque, Carme

    2008-01-01

    Very preterm (VPT) birth can account for thinning of the corpus callosum and poorer cognitive performance. Research findings about preterm and VPT adolescents usually describe a small posterior corpus callosum, although our research group has also found reductions of the anterior part, specifically the genu. The aim of the present study was to…

  9. Corpus callosum size and shape alterations in adolescent inhalant users.

    PubMed

    Takagi, Michael; Lubman, Dan I; Walterfang, Mark; Barton, Sarah; Reutens, David; Wood, Amanda; Yücel, Murat

    2013-09-01

    Inhalants, frequently abused during adolescence, are neurotoxic to white matter. We investigated the impact of inhalant misuse on the morphology of the corpus callosum (CC), the largest white matter bundle in the brain, in an adolescent sample of inhalant users [n = 14; mean age = 17.3; standard deviation (SD) = 1.7], cannabis users (n = 11; mean age = 19.7; SD = 1.7) and community controls (n = 9; mean age = 19.5; SD = 2.6). We identified significant morphological differences in the CC among inhalant users compared with community controls. There were no morphological differences between inhalant and cannabis users. Our findings may represent the early stages of neurobiological damage associated with chronic inhalant misuse. PMID:21955104

  10. Axon position within the corpus callosum determines contralateral cortical projection.

    PubMed

    Zhou, Jing; Wen, Yunqing; She, Liang; Sui, Ya-Nan; Liu, Lu; Richards, Linda J; Poo, Mu-Ming

    2013-07-16

    How developing axons in the corpus callosum (CC) achieve their homotopic projection to the contralateral cortex remains unclear. We found that axonal position within the CC plays a critical role in this projection. Labeling of nearby callosal axons in mice showed that callosal axons were segregated in an orderly fashion, with those from more medial cerebral cortex located more dorsally and subsequently projecting to more medial contralateral cortical regions. The normal axonal order within the CC was grossly disturbed when semaphorin3A/neuropilin-1 signaling was disrupted. However, the order in which axons were positioned within the CC still determined their contralateral projection, causing a severe disruption of the homotopic contralateral projection that persisted at postnatal day 30, when the normal developmental refinement of contralateral projections is completed in wild-type (WT) mice. Thus, the orderly positioning of axons within the CC is a primary determinant of how homotopic interhemispheric projections form in the contralateral cortex. PMID:23812756

  11. MRI evaluation of pathologies affecting the corpus callosum: A pictorial essay

    PubMed Central

    Kazi, Aamish Z; Joshi, Priscilla C; Kelkar, Abhimanyu B; Mahajan, Mangal S; Ghawate, Amit S

    2013-01-01

    The corpus callosum is a midline cerebral structure and has a unique embryological development pattern. In this article, we describe the pathophysiology and present imaging findings of various typical/atypical conditions affecting the corpus callosum. Since many of these pathologies have characteristic appearances on magnetic resonance imaging (MRI) and their therapeutic approaches are poles apart, ranging from medical to surgical, the neuroradiologist should be well aware of them. PMID:24604936

  12. MRI and MR spectroscopy findings of a case of subacute sclerosing panencephalitis affecting the corpus callosum.

    PubMed

    Öztürk, Mehmet; Sığırcı, Ahmet; Yakıncı, Cengiz

    2015-01-01

    Subacute sclerosing panencephalitis (SSPE) is a rare, slowly progressive, fatal, inflammatory and neurodegenerative disease that is seen mostly in children and young adolescents, and primarily affects the parieto-occipital lobes. The corpus callosum, cerebellum and basal ganglia are less frequently involved. MR spectroscopy (MRS) may illustrate the pathophysiological features of SSPE. To the best of our knowledge, this is the second report of MRS findings of corpus callosum involvement in a stage 3 SSPE case. PMID:26163552

  13. Oligodendrocyte Lineage and Subventricular Zone Response to Traumatic Axonal Injury in the Corpus Callosum

    PubMed Central

    Sullivan, Genevieve M.; Mierzwa, Amanda J.; Kijpaisalratana, Naruchorn; Tang, *Haiying; Wang, Yong; Song, Sheng-Kwei; Selwyn, Reed

    2013-01-01

    Abstract Traumatic brain injury frequently causes traumatic axonal injury (TAI) in white matter tracts. Experimental TAI in the corpus callosum of adult mice was used to examine the effects on oligodendrocyte lineage cells and myelin in conjunction with neuroimaging. The injury targeted the corpus callosum over the subventricular zone, a source of neural stem/progenitor cells. Traumatic axonal injury was produced in the rostral body of the corpus callosum by impact onto the skull at the bregma. During the first week after injury, magnetic resonance diffusion tensor imaging showed that axial diffusivity decreased in the corpus callosum and that corresponding regions exhibited significant axon damage accompanied by hypertrophic microglia and reactive astrocytes. Oligodendrocyte progenitor proliferation increased in the subventricular zone and corpus callosum. Oligodendrocytes in the corpus callosum shifted toward upregulation of myelin gene transcription. Plp/CreERT:R26IAP reporter mice showed normal reporter labeling of myelin sheaths 0 to 2 days after injury but labeling was increased between 2 and 7 days after injury. Electron microscopy revealed axon degeneration, demyelination, and redundant myelin figures. These findings expand the cell types and responses to white matter injuries that inform diffusion tensor imaging evaluation and identify pivotal white matter changes after TAI that may affect axon vulnerability vs. recovery after brain injury. PMID:24226267

  14. Automatic corpus callosum segmentation for standardized MR brain scanning

    NASA Astrophysics Data System (ADS)

    Xu, Qing; Chen, Hong; Zhang, Li; Novak, Carol L.

    2007-03-01

    Magnetic Resonance (MR) brain scanning is often planned manually with the goal of aligning the imaging plane with key anatomic landmarks. The planning is time-consuming and subject to inter- and intra- operator variability. An automatic and standardized planning of brain scans is highly useful for clinical applications, and for maximum utility should work on patients of all ages. In this study, we propose a method for fully automatic planning that utilizes the landmarks from two orthogonal images to define the geometry of the third scanning plane. The corpus callosum (CC) is segmented in sagittal images by an active shape model (ASM), and the result is further improved by weighting the boundary movement with confidence scores and incorporating region based refinement. Based on the extracted contour of the CC, several important landmarks are located and then combined with landmarks from the coronal or transverse plane to define the geometry of the third plane. Our automatic method is tested on 54 MR images from 24 patients and 3 healthy volunteers, with ages ranging from 4 months to 70 years old. The average accuracy with respect to two manually labeled points on the CC is 3.54 mm and 4.19 mm, and differed by an average of 2.48 degrees from the orientation of the line connecting them, demonstrating that our method is sufficiently accurate for clinical use.

  15. Genetic Contributions to the Midsagittal Area of the Corpus Callosum

    PubMed Central

    Phillips, Kimberley A.; Rogers, Jeffrey; Barrett, Elizabeth A.; Glahn, David C; Kochunov, Peter

    2012-01-01

    The degree to which genes and environment determine variations in brain structure and function is fundamentally important to understanding normal and disease-related patterns of neural organization and activity. We studied genetic contributions to the midsagittal area of the corpus callosum (CC) in pedigreed baboons (68 males/112 females) to replicate findings of high genetic contribution to area of the CC, reported in humans, and to determine if the heritability of the CC midsaggital area in adults was modulated by fetal development rate. Measurements of callosal area were obtained from high-resolution MRI scans. Heritability was estimated from pedigree based maximum likelihood estimation of genetic and non-genetic variance components as implemented in SOLAR. Our analyses revealed significant heritability for the total area of the CC and all of its subdivisions, with h2 = 0.46 for the total CC and h2 = .54, .37, .62, .56, and 0.29 for genu, anterior midbody, medial midbody, posterior midbody and splenium, respectively. Genetic correlation analysis demonstrated that the individual subdivisions shared between 41% and 98% of genetic variability. Combined with previous research reporting high heritability of other brain structures in baboons, these results reveal a consistent pattern of high heritability for brain morphometric measures in baboons. PMID:22856367

  16. Parametric Probability Distribution Functions for Axon Diameters of Corpus Callosum

    PubMed Central

    Sepehrband, Farshid; Alexander, Daniel C.; Clark, Kristi A.; Kurniawan, Nyoman D.; Yang, Zhengyi; Reutens, David C.

    2016-01-01

    Axon diameter is an important neuroanatomical characteristic of the nervous system that alters in the course of neurological disorders such as multiple sclerosis. Axon diameters vary, even within a fiber bundle, and are not normally distributed. An accurate distribution function is therefore beneficial, either to describe axon diameters that are obtained from a direct measurement technique (e.g., microscopy), or to infer them indirectly (e.g., using diffusion-weighted MRI). The gamma distribution is a common choice for this purpose (particularly for the inferential approach) because it resembles the distribution profile of measured axon diameters which has been consistently shown to be non-negative and right-skewed. In this study we compared a wide range of parametric probability distribution functions against empirical data obtained from electron microscopy images. We observed that the gamma distribution fails to accurately describe the main characteristics of the axon diameter distribution, such as location and scale of the mode and the profile of distribution tails. We also found that the generalized extreme value distribution consistently fitted the measured distribution better than other distribution functions. This suggests that there may be distinct subpopulations of axons in the corpus callosum, each with their own distribution profiles. In addition, we observed that several other distributions outperformed the gamma distribution, yet had the same number of unknown parameters; these were the inverse Gaussian, log normal, log logistic and Birnbaum-Saunders distributions. PMID:27303273

  17. [A case of astrocytoma of corpus callosum presented diagnostic dyspraxia].

    PubMed

    Koshimizu, K; Takeyama, E; Takeyama, E; Kizuki, H; Tei, H; Kubo, O

    1995-08-01

    A case of astrocytoma whose first clinical presentation was diagnostic dyspraxia was reported. A 38-year-old right-handed male experienced funny motion of his left hand triggered by voluntary movement of his right hand. One day, he tried to insert a coin into the vending machine with his right hand, then the left hand was against the other. One month after that event, he experienced headache and vertigo. On admission, there were no abnormal findings on neurological examination. On neuropsychological examination, he was cooperative, well orientated and attentive, and there were no callosal disconnection symptoms. Frontal lobe function tests were slightly impaired. T1-weighted MRI demonstrated irregular mixed signal intensity mass lesion extending from the genu to the body of the corpus callosum and the cingulate gyrus. This lesion was slightly enhanced with Gd-DTPA. Biopsy was performed and histological diagnosis was fibrillary astrocytoma. After irradiation and chemotherapy, he was discharged from the hospital without evident neurological deficit. About 20 cases of diagnostic dyspraxia have been reported and almost all of them were caused by cerebro-vascular disease. This is the first case of brain tumor who presented diagnostic dyspraxia. PMID:7546921

  18. Magnetic resonance findings of the corpus callosum in canine and feline lysosomal storage diseases.

    PubMed

    Hasegawa, Daisuke; Tamura, Shinji; Nakamoto, Yuya; Matsuki, Naoaki; Takahashi, Kimimasa; Fujita, Michio; Uchida, Kazuyuki; Yamato, Osamu

    2013-01-01

    Several reports have described magnetic resonance (MR) findings in canine and feline lysosomal storage diseases such as gangliosidoses and neuronal ceroid lipofuscinosis. Although most of those studies described the signal intensities of white matter in the cerebrum, findings of the corpus callosum were not described in detail. A retrospective study was conducted on MR findings of the corpus callosum as well as the rostral commissure and the fornix in 18 cases of canine and feline lysosomal storage diseases. This included 6 Shiba Inu dogs and 2 domestic shorthair cats with GM1 gangliosidosis; 2 domestic shorthair cats, 2 familial toy poodles, and a golden retriever with GM2 gangliosidosis; and 2 border collies and 3 chihuahuas with neuronal ceroid lipofuscinoses, to determine whether changes of the corpus callosum is an imaging indicator of those diseases. The corpus callosum and the rostral commissure were difficult to recognize in all cases of juvenile-onset gangliosidoses (GM1 gangliosidosis in Shiba Inu dogs and domestic shorthair cats and GM2 gangliosidosis in domestic shorthair cats) and GM2 gangliosidosis in toy poodles with late juvenile-onset. In contrast, the corpus callosum and the rostral commissure were confirmed in cases of GM2 gangliosidosis in a golden retriever and canine neuronal ceroid lipofuscinoses with late juvenile- to early adult-onset, but were extremely thin. Abnormal findings of the corpus callosum on midline sagittal images may be a useful imaging indicator for suspecting lysosomal storage diseases, especially hypoplasia (underdevelopment) of the corpus callosum in juvenile-onset gangliosidoses. PMID:24386203

  19. Magnetic Resonance Findings of the Corpus Callosum in Canine and Feline Lysosomal Storage Diseases

    PubMed Central

    Hasegawa, Daisuke; Tamura, Shinji; Nakamoto, Yuya; Matsuki, Naoaki; Takahashi, Kimimasa; Fujita, Michio; Uchida, Kazuyuki; Yamato, Osamu

    2013-01-01

    Several reports have described magnetic resonance (MR) findings in canine and feline lysosomal storage diseases such as gangliosidoses and neuronal ceroid lipofuscinosis. Although most of those studies described the signal intensities of white matter in the cerebrum, findings of the corpus callosum were not described in detail. A retrospective study was conducted on MR findings of the corpus callosum as well as the rostral commissure and the fornix in 18 cases of canine and feline lysosomal storage diseases. This included 6 Shiba Inu dogs and 2 domestic shorthair cats with GM1 gangliosidosis; 2 domestic shorthair cats, 2 familial toy poodles, and a golden retriever with GM2 gangliosidosis; and 2 border collies and 3 chihuahuas with neuronal ceroid lipofuscinoses, to determine whether changes of the corpus callosum is an imaging indicator of those diseases. The corpus callosum and the rostral commissure were difficult to recognize in all cases of juvenile-onset gangliosidoses (GM1 gangliosidosis in Shiba Inu dogs and domestic shorthair cats and GM2 gangliosidosis in domestic shorthair cats) and GM2 gangliosidosis in toy poodles with late juvenile-onset. In contrast, the corpus callosum and the rostral commissure were confirmed in cases of GM2 gangliosidosis in a golden retriever and canine neuronal ceroid lipofuscinoses with late juvenile- to early adult-onset, but were extremely thin. Abnormal findings of the corpus callosum on midline sagittal images may be a useful imaging indicator for suspecting lysosomal storage diseases, especially hypoplasia (underdevelopment) of the corpus callosum in juvenile-onset gangliosidoses. PMID:24386203

  20. Proverb comprehension in individuals with agenesis of the corpus callosum.

    PubMed

    Rehmel, Jamie L; Brown, Warren S; Paul, Lynn K

    2016-09-01

    Comprehension of non-literal language involves multiple neural systems likely involving callosal connections. We describe proverb comprehension impairments in individuals with isolated agenesis of the corpus callosum (AgCC) and normal-range general intelligence. Experiment 1 compared Gorham Proverb Test (Gorham, 1956) performance in 19 adults with AgCC and 33 neurotypical control participants of similar age, sex, and intelligence. Experiment 2 used the Proverbs subtest of the Delis-Kaplan Executive Function System (D-KEFS, 2001) to compare 19 adults with AgCC and 17 control participants with similar age, sex, and intelligence. Gorham Proverbs performance was impaired in the AgCC group for both the free-response and multiple-choice tasks. On the D-KEFS proverbs test, the AgCC group performed significantly worse on the free-response task (and all derivative scores) despite normal levels of performance on the multiple-choice task. Covarying verbal intelligence did not alter these outcomes. However, covarying a measure of non-literal language comprehension considerably reduced group differences in proverb comprehension on the Gorham test, but had little effect on the D-KEFS group differences. The difference between groups seemed to be greatest when participants had to generate their own interpretation (free response), or in the multiple choice format when the test included many proverbs that were likely to be less familiar. Taken together, the results of this study clearly show that proverb comprehension is diminished in individuals with AgCC compared to their peers. PMID:27448531

  1. Lipoma of corpus callosum associated with dysraphic lesions and trisomy 13

    SciTech Connect

    Wainwright, H.; Bowen, R.; Radcliffe, M.

    1995-05-22

    We report on a further case of corpus callosal lipoma and frontal cranial defects. Most cases in the literature of corpus callosal lipoma in association with {open_quotes}dysraphic{close_quotes} lesions have been frontal in location. Malformation of the corpus callosum is said to be associated with 50% of these lipomas. Trisomy 13 was confirmed by the 13q14 cosmid probe on paraffin-embedded liver tissue. 19 refs., 5 figs.

  2. Corpus callosum abnormalities in women with borderline personality disorder and comorbid attention-deficit hyperactivity disorder

    PubMed Central

    Rüsch, Nicolas; Luders, Eileen; Lieb, Klaus; Zahn, Roland; Ebert, Dieter; Thompson, Paul M.; Toga, Arthur W.; van Elst, Ludger Tebartz

    2007-01-01

    Objective Decreased brain volumes in prefrontal, limbic and parietal areas have been found in women with borderline personality disorder (BPD). Recent models suggest impaired structural and functional connectivity in this condition. To investigate this, we studied the thickness of the corpus callosum, the largest connecting fibre bundle in the human brain. Methods We acquired magnetic resonance imaging scans from 20 healthy women and 20 women with BPD and comorbid attention-deficit hyperactivity disorder. A novel computational mesh-based method was applied to measure callosal thickness at high spatial resolution. Results Women with BPD had a thinner isthmus of the corpus callosum, compared with healthy women. In the patient group, a history of childhood sexual abuse was associated with a thinner posterior body of the corpus callosum. Conclusion Interhemispheric structural connectivity involving parietal and temporal areas may be impaired in women with BPD and comorbid attention-deficit hyperactivity disorder. PMID:18043765

  3. Corpus Callosum Area and Brain Volume in Autism Spectrum Disorder: Quantitative Analysis of Structural MRI from the ABIDE Database

    ERIC Educational Resources Information Center

    Kucharsky Hiess, R.; Alter, R.; Sojoudi, S.; Ardekani, B. A.; Kuzniecky, R.; Pardoe, H. R.

    2015-01-01

    Reduced corpus callosum area and increased brain volume are two commonly reported findings in autism spectrum disorder (ASD). We investigated these two correlates in ASD and healthy controls using T1-weighted MRI scans from the Autism Brain Imaging Data Exchange (ABIDE). Automated methods were used to segment the corpus callosum and intracranial…

  4. Psychosis in Apert's syndrome with partial agenesis of the corpus callosum.

    PubMed Central

    Gupta, S; Popli, A

    1995-01-01

    A 19-year-old male with Apert's syndrome developed psychotic symptoms that responded to haloperidol. He was also found to have partial agenesis of the corpus callosum and enlarged lateral ventricles on a head CT scan. The implications of these findings in the context of psychotic symptoms are discussed. There are no previous reports of psychosis in patients with Apert's syndrome. PMID:7647085

  5. Congenital and Acquired Abnormalities of the Corpus Callosum: A Pictorial Essay

    PubMed Central

    Krupa, Katarzyna; Bekiesinska-Figatowska, Monika

    2013-01-01

    The purpose of this review is to illustrate the wide spectrum of lesions in the corpus callosum, both congenital and acquired: developmental abnormalities, phakomatoses, neurometabolic disorders, demyelinating diseases, infection and inflammation, vascular lesions, neoplasms, traumatic and iatrogenic injury, and others. Cases include fetuses, children, and adults with rich iconography from the authors' own archive. PMID:24027754

  6. A Two-Year Longitudinal MRI Study of the Corpus Callosum in Autism

    ERIC Educational Resources Information Center

    Frazier, Thomas W.; Keshavan, Matcheri S.; Minshew, Nancy J.; Hardan, Antonio Y.

    2012-01-01

    A growing body of literature has identified size reductions of the corpus callosum (CC) in autism. However, to our knowledge, no published studies have reported on the growth of CC volumes in youth with autism. Volumes of the total CC and its sub-divisions were obtained from 23 male children with autism and 23 age- and gender-matched controls at…

  7. Reduced White Matter Connectivity in the Corpus Callosum of Children with Tourette Syndrome

    ERIC Educational Resources Information Center

    Plessen, Kerstin J.; Gruner, Renate; Lundervold, Arvid; Hirsch, Jochen G.; Xu, Dongrong; Bansal, Ravi; Hammar, Asa; Lundervold, Astri J.; Wentzel-Larsen, Tore; Lie, Stein Atle; Gass, Achim; Peterson, Bradley S.; Hugdahl, Kenneth

    2006-01-01

    Background: Brain imaging studies have revealed anatomical anomalies in the brains of individuals with Tourette syndrome (TS). Prefrontal regions have been found to be larger and the corpus callosum (CC) area smaller in children and young adults with TS compared with healthy control subjects, and these anatomical features have been understood to…

  8. Quantitative Analysis of the Shape of the Corpus Callosum in Patients with Autism and Comparison Individuals

    ERIC Educational Resources Information Center

    Casanova, Manuel F.; El-Baz, Ayman; Elnakib, Ahmed; Switala, Andrew E.; Williams, Emily L.; Williams, Diane L.; Minshew, Nancy J.; Conturo, Thomas E.

    2011-01-01

    Multiple studies suggest that the corpus callosum in patients with autism is reduced in size. This study attempts to elucidate the nature of this morphometric abnormality by analyzing the shape of this structure in 17 high-functioning patients with autism and an equal number of comparison participants matched for age, sex, IQ, and handedness. The…

  9. A 23-Year Review of Communication Development in an Individual with Agenesis of the Corpus Callosum.

    ERIC Educational Resources Information Center

    Stickles, Judith L.; Schilmoeller, Gary L.; Schilmoeller, Kathryn J.

    2002-01-01

    Twenty-three years of observation and testing of the communication skills of a male with agenesis of the corpus callosum and normal IQ revealed initial weakness in language. Difficulties with fluent speech persisted into young adulthood. With intensive intervention, communication and academic skills developed and the participant completed high…

  10. Psychological Correlates of Handedness and Corpus Callosum Asymmetry in Autism: The Left Hemisphere Dysfunction Theory Revisited

    ERIC Educational Resources Information Center

    Floris, Dorothea L.; Chura, Lindsay R.; Holt, Rosemary J.; Suckling, John; Bullmore, Edward T.; Baron-Cohen, Simon; Spencer, Michael D.

    2013-01-01

    Rightward cerebral lateralization has been suggested to be involved in the neuropathology of autism spectrum conditions. We investigated functional and neuroanatomical asymmetry, in terms of handedness and corpus callosum measurements in male adolescents with autism, their unaffected siblings and controls, and their associations with executive…

  11. Social and Behavioral Problems of Children with Agenesis of the Corpus Callosum

    ERIC Educational Resources Information Center

    Badaruddin, Denise H.; Andrews, Glena L.; Bolte, Sven; Schilmoeller, Kathryn J.; Schilmoeller, Gary; Paul, Lynn K.; Brown, Warren S.

    2007-01-01

    Archival data from a survey of parent observations was used to determine the prevalence of social and behavioral problems in children with agenesis of the corpus callosum (ACC). Parent observations were surveyed using the Child Behavior Checklist (CBCL) for 61 children with ACC who were selected from the archive based on criteria of motor…

  12. Corpus Callosum Size is Linked to Dichotic Deafness and Hemisphericity, Not Sex or Handedness

    ERIC Educational Resources Information Center

    Morton, Bruce E.; Rafto, Stein E.

    2006-01-01

    Individuals differ in the number of corpus callosum (CC) nerve fibers interconnecting their cerebral hemispheres by about threefold. Early reports suggested that males had smaller CCs than females. This was often interpreted to support the concept that the male brain is more "lateralized" or "specialized," thus accounting for presumed male…

  13. Tractography of the spider monkey (Ateles geoffroyi) corpus callosum using diffusion tensor magnetic resonance imaging.

    PubMed

    Platas-Neri, Diana; Hidalgo-Tobón, Silvia; de Celis Alonso, Benito; da Celis Alonso, Benito; de León, Fernando Chico-Ponce; Muñoz-Delgado, Jairo; Phillips, Kimberley A

    2015-01-01

    The objective of this research was to describe the organization, connectivity and microstructure of the corpus callosum of the spider monkey (Ateles geoffroyi). Non-invasive magnetic resonance imaging and diffusion-tensor imaging were obtained from three subjects using a 3T Philips scanner. We hypothesized that the arrangement of fibers in spider monkeys would be similar to that observed in other non-human primates. A repeated measure (n = 3) of fractional anisotropy values was obtained of each subject and for each callosal subdivision. Measurements of the diffusion properties of corpus callosum fibers exhibited a similar pattern to those reported in the literature for humans and chimpanzees. No statistical difference was reached when comparing this parameter between the different CC regions (p = 0.066). The highest fractional anisotropy values corresponded to regions projecting from the corpus callosum to the posterior cortical association areas, premotor and supplementary motor cortices. The lowest fractional anisotropy corresponded to projections to motor and sensory cortical areas. Analyses indicated that approximately 57% of the fibers projects to the frontal cortex and 43% to the post-central cortex. While this study had a small sample size, the results provided important information concerning the organization of the corpus callosum in spider monkeys. PMID:25693078

  14. Tractography of the Spider Monkey (Ateles geoffroyi) Corpus Callosum Using Diffusion Tensor Magnetic Resonance Imaging

    PubMed Central

    Platas-Neri, Diana; Hidalgo-Tobón, Silvia; da Celis Alonso, Benito; de León, Fernando Chico-Ponce; Muñoz-Delgado, Jairo; Phillips, Kimberley A.

    2015-01-01

    The objective of this research was to describe the organization, connectivity and microstructure of the corpus callosum of the spider monkey (Ateles geoffroyi). Non-invasive magnetic resonance imaging and diffusion-tensor imaging were obtained from three subjects using a 3T Philips scanner. We hypothesized that the arrangement of fibers in spider monkeys would be similar to that observed in other non-human primates. A repeated measure (n = 3) of fractional anisotropy values was obtained of each subject and for each callosal subdivision. Measurements of the diffusion properties of corpus callosum fibers exhibited a similar pattern to those reported in the literature for humans and chimpanzees. No statistical difference was reached when comparing this parameter between the different CC regions (p = 0.066). The highest fractional anisotropy values corresponded to regions projecting from the corpus callosum to the posterior cortical association areas, premotor and supplementary motor cortices. The lowest fractional anisotropy corresponded to projections to motor and sensory cortical areas. Analyses indicated that approximately 57% of the fibers projects to the frontal cortex and 43% to the post-central cortex. While this study had a small sample size, the results provided important information concerning the organization of the corpus callosum in spider monkeys. PMID:25693078

  15. Corpus Callosum Size and Diffusion Tensor Anisotropy in Adolescents and Adults with Schizophrenia

    PubMed Central

    Balevich, Emily C.; Haznedar, M. Mehmet; Wang, Eugene; Newmark, Randall E.; Bloom, Rachel; Schneiderman, Jason S.; Aronowitz, Jonathan; Tang, Cheuk Y.; Chu, King-Wai; Byne, William; Buchsbaum, Monte S.; Hazlett, Erin A.

    2015-01-01

    The corpus callosum has been implicated as a region of dysfunctional connectivity in schizophrenia, but the association between age and callosal pathology is unclear. Magnetic resonance imaging (MRI) and diffusion-tensor imaging (DTI) were performed on adults (n=34) and adolescents (n=17) with schizophrenia and adult (n=33) and adolescent (n=15) age- and sex-matched healthy controls. The corpus callosum was manually traced on each participant’s MRI, and the DTI scan was co-registered to the MRI. The corpus callosum was divided into five anteroposterior segments. Area and anisotropy were calculated for each segment. Both patient groups demonstrated reduced callosal anisotropy; however, the adolescents exhibited reductions mostly in anterior regions while the reductions were more prominent in posterior regions of the adults. The adolescent patients showed greater decreases in absolute area as compared with the adult patients, particularly in the anterior segments. However, the adults showed greater reductions when area was considered relative to whole brain white matter volume. Our results suggest that the initial stages of the illness are characterized by deficiencies in frontal connections, and the chronic phase is characterized by deficits in the posterior corpus callosum; or, alternatively, adolescent-onset schizophrenia may represent a different or more severe form of the illness. PMID:25637358

  16. Progesterone and nestorone promote myelin regeneration in chronic demyelinating lesions of corpus callosum and cerebral cortex.

    PubMed

    El-Etr, Martine; Rame, Marion; Boucher, Celine; Ghoumari, Abdel M; Kumar, Narender; Liere, Philippe; Pianos, Antoine; Schumacher, Michael; Sitruk-Ware, Regine

    2015-01-01

    Multiple Sclerosis affects mainly women and consists in intermittent or chronic damages to the myelin sheaths, focal inflammation, and axonal degeneration. Current therapies are limited to immunomodulators and antiinflammatory drugs, but there is no efficient treatment for stimulating the endogenous capacity of myelin repair. Progesterone and synthetic progestins have been shown in animal models of demyelination to attenuate myelin loss, reduce clinical symptoms severity, modulate inflammatory responses and partially reverse the age-dependent decline in remyelination. Moreover, progesterone has been demonstrated to promote myelin formation in organotypic cultures of cerebellar slices. In the present study, we show that progesterone and the synthetic 19-nor-progesterone derivative Nestorone® promote the repair of severe chronic demyelinating lesions induced by feeding cuprizone to female mice for up to 12 weeks. Progesterone and Nestorone increase the density of NG2(+) oligodendrocyte progenitor cells and CA II(+) mature oligodendrocytes and enhance the formation of myelin basic protein (MBP)- and proteolipid protein (PLP)-immunoreactive myelin. However, while demyelination in response to cuprizone was less marked in corpus callosum than in cerebral cortex, remyelination appeared earlier in the former. The remyelinating effect of progesterone was progesterone receptor (PR)-dependent, as it was absent in PR-knockout mice. Progesterone and Nestorone also decreased (but did not suppress) neuroinflammatory responses, specifically astrocyte and microglial cell activation. Therefore, some progestogens are promising therapeutic candidates for promoting the regeneration of myelin. PMID:25092805

  17. Cognitive impairments associated with corpus callosum infarction: a ten cases study.

    PubMed

    Huang, Xiaoqin; Du, Xiangnan; Song, Haiqing; Zhang, Qian; Jia, Jianping; Xiao, Tianyi; Wu, Jian

    2015-01-01

    The aim of this study was to determine whether the cognitive impairment is associated with corpus callosum infarctions. Ten corpus callosum infarction patients were enrolled in this study. Their emotions, cognitive and language abilities, memory, comprehensive perception were assessed using the Chinese version of following measures: Mini Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), World Health Organization-University of California-Los Angeles Auditory Verbal Learning Test (WHO-UCLA AVLT), Wechsler Adult Intelligence Scale (WAIS) Digit Span subtest and so on. The same measurements were performed on healthy control participants as contrast for analysis. Infarction most frequently occurred in the body and/or splenium of the corpus callosum. The scores of the most cognitive tests in the corpus callosum infarction patients were significantly worse than those of the control participants (P<0.05). Except for the naming ability, the patients showed significantly poorer performance at the overall level of MMSE than the controls did (P<0.05). Consistently, the results of MoCA suggested a significant reduction in visuospatial abilities of execution, orientation, attention, calculation, delayed memory, language, and repetition capabilities in the patients with respect to the control (P<0.05). In addition, the scores in the case group were significantly worse than those in the control group in the auditory word learning test, digital span and Rey complex figure test (P<0.05). Corpus callosum infarction can cause cognitive dysfunction, which poses obstacles to memory in the acute phase, accompanied by different degrees of decline in visuospatial abilities, attention and calculating abilities. PMID:26885171

  18. Cognitive impairments associated with corpus callosum infarction: a ten cases study

    PubMed Central

    Huang, Xiaoqin; Du, Xiangnan; Song, Haiqing; Zhang, Qian; Jia, Jianping; Xiao, Tianyi; Wu, Jian

    2015-01-01

    The aim of this study was to determine whether the cognitive impairment is associated with corpus callosum infarctions. Ten corpus callosum infarction patients were enrolled in this study. Their emotions, cognitive and language abilities, memory, comprehensive perception were assessed using the Chinese version of following measures: Mini Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), World Health Organization-University of California-Los Angeles Auditory Verbal Learning Test (WHO-UCLA AVLT), Wechsler Adult Intelligence Scale (WAIS) Digit Span subtest and so on. The same measurements were performed on healthy control participants as contrast for analysis. Infarction most frequently occurred in the body and/or splenium of the corpus callosum. The scores of the most cognitive tests in the corpus callosum infarction patients were significantly worse than those of the control participants (P<0.05). Except for the naming ability, the patients showed significantly poorer performance at the overall level of MMSE than the controls did (P<0.05). Consistently, the results of MoCA suggested a significant reduction in visuospatial abilities of execution, orientation, attention, calculation, delayed memory, language, and repetition capabilities in the patients with respect to the control (P<0.05). In addition, the scores in the case group were significantly worse than those in the control group in the auditory word learning test, digital span and Rey complex figure test (P<0.05). Corpus callosum infarction can cause cognitive dysfunction, which poses obstacles to memory in the acute phase, accompanied by different degrees of decline in visuospatial abilities, attention and calculating abilities. PMID:26885171

  19. Corpus callosum arteriovenous malformation with persistent trigeminal artery.

    PubMed

    Mohanty, Chandan B; Devi, B Indira; Somanna, Sampath; Bhat, Dhananjaya I; Dawn, Rose

    2011-12-01

    A 13-year-old boy presented with an intracerebral haematoma secondary to a large corpus callosal arteriovenous malformation (AVM) with an associated persistent trigeminal artery, and was treated with Gamma-Knife Radiosurgery for the AVM. This report discusses the embryological basis, radiological features and various classifications of this rare vascular anomaly. PMID:21501055

  20. Bart’s Syndrome Associated Corpus Callosum Agenesis and Choanal Atresia

    PubMed Central

    SAEED, Muhammad; HAQ, Anwar ul; QADIR, Khaqan

    2014-01-01

    Objective Bart’s syndrome is defined as congenital localized absence of skin, and associated with epidermolysis bullosa. A newborn with Bart’s syndrome is reported because it is a very rare condition, especially when associated with corpus callosum agenesis and concomitant choanal atresia. Clinically it is characterized by raw beefy areas of denuded skin mainly on hands and feet. We report a rare case of a term female newborn born to non-consanguineous parents who presented with congenital absence of skin in, face, trunk and extremities. To the best of our knowledge, this is the first report presenting a case of Bart’s syndrome associated with corpus callosum agenesis. PMID:25657775

  1. The split-brain neonate: a surgical method for corpus callosum section in newborn kittens.

    PubMed

    Sechzer, J A; Folstein, S E; Geiger, E H; Mervis, R F

    1976-07-01

    One way to determine the importance of interhemispheric interaction in the development of adaptive and acquired behavior is to section completely the corpus callosum about the time of birth before myelination commences and before any significant hemispheric interaction takes place. Therefore, we developed a technique for commissurotomy in the neonatal kitten 36 to 72 hr of age. A specially designed "commissurotomy knife" was used which eliminated retraction of the hemispheres. Histology showed completeness of corpus callosum section as well as commissure of the fornix without any apparent damage to cortical or subcortical structures. This technique meets the following criteria: (1) reproducibility or lesions without additional nonspecific damage; (2)minimal exposure and manipulation of the delicate newborn brain: (3) brief operational procedure minimizing risk of infection; and (4) low mortality rate. PMID:782979

  2. Altered corpus callosum morphology associated with autism over the first 2 years of life.

    PubMed

    Wolff, Jason J; Gerig, Guido; Lewis, John D; Soda, Takahiro; Styner, Martin A; Vachet, Clement; Botteron, Kelly N; Elison, Jed T; Dager, Stephen R; Estes, Annette M; Hazlett, Heather C; Schultz, Robert T; Zwaigenbaum, Lonnie; Piven, Joseph

    2015-07-01

    Numerous brain imaging studies indicate that the corpus callosum is smaller in older children and adults with autism spectrum disorder. However, there are no published studies examining the morphological development of this connective pathway in infants at-risk for the disorder. Magnetic resonance imaging data were collected from 270 infants at high familial risk for autism spectrum disorder and 108 low-risk controls at 6, 12 and 24 months of age, with 83% of infants contributing two or more data points. Fifty-seven children met criteria for ASD based on clinical-best estimate diagnosis at age 2 years. Corpora callosa were measured for area, length and thickness by automated segmentation. We found significantly increased corpus callosum area and thickness in children with autism spectrum disorder starting at 6 months of age. These differences were particularly robust in the anterior corpus callosum at the 6 and 12 month time points. Regression analysis indicated that radial diffusivity in this region, measured by diffusion tensor imaging, inversely predicted thickness. Measures of area and thickness in the first year of life were correlated with repetitive behaviours at age 2 years. In contrast to work from older children and adults, our findings suggest that the corpus callosum may be larger in infants who go on to develop autism spectrum disorder. This result was apparent with or without adjustment for total brain volume. Although we did not see a significant interaction between group and age, cross-sectional data indicated that area and thickness differences diminish by age 2 years. Regression data incorporating diffusion tensor imaging suggest that microstructural properties of callosal white matter, which includes myelination and axon composition, may explain group differences in morphology. PMID:25937563

  3. Diffusion Tensor Imaging, White Matter lesions, the Corpus Callosum and Gait in the Elderly

    PubMed Central

    Bhadelia, Refeeque A.; Price, Lori Lyn; Tedesco, Kurtis L.; Scott, Tammy; Qiu, Wei Qiao; Patz, Samuel; Folstein, Marshal; Rosenberg, Irwin; Caplan, Louis R.; Bergethon, Peter

    2009-01-01

    Background and Purpose Gait impairment is common in the elderly, especially those with stroke and white matter hyperintensities (WMH) on conventional brain MRI. Diffusion Tensor Imaging (DTI) is more sensitive to white matter damage than conventional MRI. The relationship between DTI measures and gait has not been previously evaluated. Our purpose was to investigate the relationship between the integrity of white matter in the corpus callosum as determined by DTI and quantitative measures of gait in the elderly. Methods One hundred seventy-three participants of a community-dwelling elderly cohort had neurological and neuropsychological examinations and brain MRI. Gait function was measured by Tinetti gait (0-12), balance (0-16) and total (0-28) scores. DTI assessed Fractional Anisotropy in the genu and splenium of the corpus callosum. Conventional MRI was used to evaluate for brain infarcts and WMH volume. Results Participants with abnormal gait had low fractional anisotropy in the genu of the corpus callosum but not the splenium. Multiple regressions analyses showed an independent association between these genu abnormalities and all three Tinetti scores (p <0.001). This association remained significant after adding MRI infarcts and WMH volume to the analysis. Conclusions The independent association between quantitative measures of gait function and DTI findings shows that white matter integrity in the genu of corpus callosum is an important marker of gait in the elderly. DTI analyses of white matter tracts in brain and spinal cord may improve knowledge about the pathophysiology of gait impairment and help target clinical interventions. PMID:19797696

  4. A de novo mutation in PRICKLE1 in fetal agenesis of the corpus callosum and polymicrogyria

    PubMed Central

    Bassuk, Alexander G.; Sherr, Elliott H.

    2016-01-01

    Homozygous recessive mutations in the PRICKLE1 gene were originally reported in three consanguineous families with myoclonic epilepsy. Subsequently, several studies have identified neurological abnormalities in animal models with both heterozygous and homozygous mutations in PRICKLE1 orthologues, including epilepsy in flies and in mice with heterozygous PRICKLE1 mutations. We describe a fetus with a novel de novo mutation in PRICKLE1 associated with agenesis of the corpus callosum. PMID:26727662

  5. Rubinstein-Taybi syndrome with agenesis of corpus callosum.

    PubMed

    Mishra, Shubhankar; Agarwalla, Sunil Kumar; Potpalle, Dnyaneshwar Ramesh; Dash, Nishant Nilotpal

    2015-01-01

    Rubinstein-Taybi syndrome (RSTS) is a rare genetic disorder with characteristic morphological anomaly. Our patient was a 4.5-year-old girl came with features like broad thumbs, downward slanting palpebral fissures and mental retardation. Systemic abnormalities such as repeated infection, seizure with developmental delay were also associated with it. She was having head banging behavior abnormal slurring speech, incoordination while transferring things from one hand to other. Galaxy of clinical pictures and magnetic resonance imaging report helped to clinch the diagnosis as a case of "RSTS with corpus callosal agenesis" which to the best of our knowledge has never been reported in past from India. PMID:26167229

  6. Rubinstein–Taybi syndrome with agenesis of corpus callosum

    PubMed Central

    Mishra, Shubhankar; Agarwalla, Sunil Kumar; Potpalle, Dnyaneshwar Ramesh; Dash, Nishant Nilotpal

    2015-01-01

    Rubinstein–Taybi syndrome (RSTS) is a rare genetic disorder with characteristic morphological anomaly. Our patient was a 4.5-year-old girl came with features like broad thumbs, downward slanting palpebral fissures and mental retardation. Systemic abnormalities such as repeated infection, seizure with developmental delay were also associated with it. She was having head banging behavior abnormal slurring speech, incoordination while transferring things from one hand to other. Galaxy of clinical pictures and magnetic resonance imaging report helped to clinch the diagnosis as a case of “RSTS with corpus callosal agenesis” which to the best of our knowledge has never been reported in past from India. PMID:26167229

  7. MIR137HG risk variant rs1625579 genotype is related to corpus callosum volume in schizophrenia

    PubMed Central

    Patel, Veena S.; Kelly, Sinead; Wright, Carrie; Gupta, Cota Navin; Arias-Vasquez, Alejandro; Perrone-Bizzozero, Nora; Ehrlich, Stefan; Wang, Lei; Bustillo, Juan R.; Morris, Derek; Corvin, Aiden; Cannon, Dara M.; McDonald, Colm; Donohoe, Gary; Calhoun, Vince D.; Turner, Jessica A.

    2015-01-01

    Genome-wide association studies implicate the MIR137HG risk variant rs1625579 (MIR137HGrv) within the host gene for microRNA-137 as a potential regulator of schizophrenia susceptibility. We examined the influence of MIR137HGrv genotype on 17 subcortical and callosal volumes in a large sample of individuals with schizophrenia and healthy controls (n=841). Although the volumes were overall reduced relative to healthy controls, for individuals with schizophrenia the homozygous MIR137HGrv risk genotype was associated with attenuated reduction of mid-posterior corpus callosum volume (p=0.001), along with trend-level effects in the adjacent central and posterior corpus callosum. These findings are unique in the literature and remain robust after analysis in ethnically homogenous and single-scanner subsets of the larger sample. Thus, our study suggests that the mechanisms whereby MIR137HGrv works to increase schizophrenia risk are not those that generate the corpus callosum volume reductions commonly found in the disorder. PMID:26123324

  8. Pediatric neurofunctional intervention in agenesis of the corpus callosum: a case report☆

    PubMed Central

    Pacheco, Sheila Cristina da Silva; Queiroz, Ana Paula Adriano; Niza, Nathália Tiepo; da Costa, Letícia Miranda Resende; Ries, Lilian Gerdi Kittel

    2014-01-01

    Objective: To describe a clinical report pre- and post-neurofunctional intervention in a case of agenesis of the corpus callosum. Case description: Preterm infant with corpus callosum agenesis and hypoplasia of the cerebellum vermis and lateral ventricles, who, at the age of two years, started the proposed intervention. Functional performance tests were used such as the neurofunctional evaluation, the Gross Motor Function Measure and the Gross Motor Function Classification System. In the initial evaluation, absence of equilibrium reactions, postural transfers, deficits in manual and trunk control were observed. The intervention was conducted with a focus on function, prioritizing postural control and guidance of the family to continue care in the home environment. After the intervention, there was an improvement of body reactions, postural control and movement acquisition of hands and limbs. The intervention also showed improvement in functional performance. Comments: Postural control and transfers of positions were benefited by the neurofunction intervention in this case of agenesis of the corpus callosum. The approach based on function with activities that involve muscle strengthening and balance reactions training, influenced the acquisition of a more selective motor behavior. PMID:25479858

  9. Clinical, genetic and imaging findings identify new causes for corpus callosum development syndromes

    PubMed Central

    Edwards, Timothy J.; Sherr, Elliott H.; Barkovich, A. James

    2014-01-01

    The corpus callosum is the largest fibre tract in the brain, connecting the two cerebral hemispheres, and thereby facilitating the integration of motor and sensory information from the two sides of the body as well as influencing higher cognition associated with executive function, social interaction and language. Agenesis of the corpus callosum is a common brain malformation that can occur either in isolation or in association with congenital syndromes. Understanding the causes of this condition will help improve our knowledge of the critical brain developmental mechanisms required for wiring the brain and provide potential avenues for therapies for callosal agenesis or related neurodevelopmental disorders. Improved genetic studies combined with mouse models and neuroimaging have rapidly expanded the diverse collection of copy number variations and single gene mutations associated with callosal agenesis. At the same time, advances in our understanding of the developmental mechanisms involved in corpus callosum formation have provided insights into the possible causes of these disorders. This review provides the first comprehensive classification of the clinical and genetic features of syndromes associated with callosal agenesis, and provides a genetic and developmental framework for the interpretation of future research that will guide the next advances in the field. PMID:24477430

  10. Processing Speed Delays Contribute to Executive Function Deficits in Individuals with Agenesis of the Corpus Callosum

    PubMed Central

    Marco, Elysa J.; Harrell, Kathryn M.; Brown, Warren S.; Hill, Susanna S.; Jeremy, Rita J.; Kramer, Joel H.; Sherr, Elliott H.; Paul, Lynn K.

    2013-01-01

    Corpus callosum malformation and dysfunction are increasingly recognized causes of cognitive and behavioral disability. Individuals with agenesis of the corpus callosum (AgCC) offer unique insights regarding the cognitive skills that depend specifically upon callosal connectivity. We examined the impact of AgCC on cognitive inhibition, flexibility, and processing speed using the Color-Word Interference Test (CWIT) and Trail Making Test (TMT) from the Delis-Kaplan Executive Function System. We compared 36 individuals with AgCC and IQs within the normal range to 56 matched controls. The AgCC cohort was impaired on timed measures of inhibition and flexibility; however, group differences on CWIT Inhibition, CWIT Inhibition/Switching and TMT Number-Letter Switching appear to be largely explained by slow performance in basic operations such as color naming and letter sequencing. On CWIT Inhibition/Switching, the AgCC group was found to commit significantly more errors which suggests that slow performance is not secondary to a cautious strategy. Therefore, while individuals with agenesis of the corpus callosum show real deficits on tasks of executive function, this impairment appears to be primarily a consequence of slow cognitive processing. Additional studies are needed to investigate the impact of AgCC on other aspects of higher order cortical function. PMID:22390821

  11. Maturation of Corpus Callosum Anterior Midbody Is Associated with Neonatal Motor Function in Eight Preterm-Born Infants

    PubMed Central

    Mathew, Preethi; Pannek, Kerstin; D'Acunto, M. Giulia; Guzzetta, Andrea; Rose, Stephen E.; Colditz, Paul B.; Finnigan, Simon

    2013-01-01

    Background. The etiology of motor impairments in preterm infants is multifactorial and incompletely understood. Whether corpus callosum development is related to impaired motor function is unclear. Potential associations between motor-related measures and diffusion tensor imaging (DTI) of the corpus callosum in preterm infants were explored. Methods. Eight very preterm infants (gestational age of 28–32 weeks) underwent the Hammersmith neonatal neurological examination and DTI assessments at gestational age of 42 weeks. The total Hammersmith score and a motor-specific score (sum of Hammersmith motor subcategories) were calculated. Six corpus callosum regions of interest were defined on the mid-sagittal DTI slice—genu, rostral body, anterior midbody, posterior midbody, isthmus, and splenium. The fractional anisotropy (FA) and mean diffusivity (MD) of these regions were computed, and correlations between these and Hammersmith measures were sought. Results. Anterior midbody FA measures correlated positively with total Hammersmith (rho = 0.929, P = 0.001) and motor-specific scores (rho = 0.857, P = 0.007). Total Hammersmith scores also negatively correlated with anterior midbody MD measures (rho = −0.714, P = 0.047). Discussion. These results suggest the integrity of corpus callosum axons, particularly anterior midbody axons, is important in mediating neurological functions. Greater callosal maturation was associated with greater motor function. Corpus callosum DTI may prove to be a valuable screening or prognostic marker. PMID:23509639

  12. Automatic corpus callosum segmentation using a deformable active Fourier contour model

    NASA Astrophysics Data System (ADS)

    Vachet, Clement; Yvernault, Benjamin; Bhatt, Kshamta; Smith, Rachel G.; Gerig, Guido; Cody Hazlett, Heather; Styner, Martin

    2012-03-01

    The corpus callosum (CC) is a structure of interest in many neuroimaging studies of neuro-developmental pathology such as autism. It plays an integral role in relaying sensory, motor and cognitive information from homologous regions in both hemispheres. We have developed a framework that allows automatic segmentation of the corpus callosum and its lobar subdivisions. Our approach employs constrained elastic deformation of flexible Fourier contour model, and is an extension of Szekely's 2D Fourier descriptor based Active Shape Model. The shape and appearance model, derived from a large mixed population of 150+ subjects, is described with complex Fourier descriptors in a principal component shape space. Using MNI space aligned T1w MRI data, the CC segmentation is initialized on the mid-sagittal plane using the tissue segmentation. A multi-step optimization strategy, with two constrained steps and a final unconstrained step, is then applied. If needed, interactive segmentation can be performed via contour repulsion points. Lobar connectivity based parcellation of the corpus callosum can finally be computed via the use of a probabilistic CC subdivision model. Our analysis framework has been integrated in an open-source, end-to-end application called CCSeg both with a command line and Qt-based graphical user interface (available on NITRC). A study has been performed to quantify the reliability of the semi-automatic segmentation on a small pediatric dataset. Using 5 subjects randomly segmented 3 times by two experts, the intra-class correlation coefficient showed a superb reliability (0.99). CCSeg is currently applied to a large longitudinal pediatric study of brain development in autism.

  13. Severe psychiatric disturbance and abnormalities of the corpus callosum: review and case series.

    PubMed Central

    David, A S; Wacharasindhu, A; Lishman, W A

    1993-01-01

    The association between developmental defects of the corpus callosum and major psychiatric disturbance is discussed with a review of published cases. Seven new cases are presented, of which four had clear psychotic symptoms, two receiving a diagnosis of schizophrenia. Of the remainder, one had a developmental disorder affecting social interaction and speech which could be classed as Asperger's syndrome, one had a personality disorder with depressive and conversion symptoms, and the last was an adolescent boy with severe behavioural problems. The difficulties in determining the precise relevance of the callosal anomalies to these clinical manifestations are discussed especially since the prevalence of such anomalies in the population is uncertain. Images PMID:8429328

  14. Bilateral cleft lip and palate, hypertelorism with agenesis of corpus callosum.

    PubMed

    Balaji, S M

    2016-01-01

    Agenesis of corpus callosum (ACC) can have various development abnormalities spectrum. These include delay in milestones to complex neuropsychiatric manifestations. Following case report highlights the case of a young infant presenting with associated features including bilateral cleft lip and palate and hypertelorism. The kid was refused treatment at several centers owing to the central nervous system abnormality. This case reports highlight the ACC as a comorbid diagnosis in cleft lip and palate patient with hypertelorism perhaps owing to ignorance and fear of this apparently innocuous congenital malformation. PMID:27054869

  15. Structural Organization of the Corpus Callosum Predicts Attentional Shifts after Continuous Theta Burst Stimulation

    PubMed Central

    Humphreys, Glyn W.; Sotiropoulos, Stamatios N.; Kennard, Christopher; Cazzoli, Dario

    2015-01-01

    Repetitive transcranial magnetic stimulation (rTMS) applied over the right posterior parietal cortex (PPC) in healthy participants has been shown to trigger a significant rightward shift in the spatial allocation of visual attention, temporarily mimicking spatial deficits observed in neglect. In contrast, rTMS applied over the left PPC triggers a weaker or null attentional shift. However, large interindividual differences in responses to rTMS have been reported. Studies measuring changes in brain activation suggest that the effects of rTMS may depend on both interhemispheric and intrahemispheric interactions between cortical loci controlling visual attention. Here, we investigated whether variability in the structural organization of human white matter pathways subserving visual attention, as assessed by diffusion magnetic resonance imaging and tractography, could explain interindividual differences in the effects of rTMS. Most participants showed a rightward shift in the allocation of spatial attention after rTMS over the right intraparietal sulcus (IPS), but the size of this effect varied largely across participants. Conversely, rTMS over the left IPS resulted in strikingly opposed individual responses, with some participants responding with rightward and some with leftward attentional shifts. We demonstrate that microstructural and macrostructural variability within the corpus callosum, consistent with differential effects on cross-hemispheric interactions, predicts both the extent and the direction of the response to rTMS. Together, our findings suggest that the corpus callosum may have a dual inhibitory and excitatory function in maintaining the interhemispheric dynamics that underlie the allocation of spatial attention. SIGNIFICANCE STATEMENT The posterior parietal cortex (PPC) controls allocation of attention across left versus right visual fields. Damage to this area results in neglect, characterized by a lack of spatial awareness of the side of space

  16. Agenesis of the corpus callosum: symptoms consistent with developmental disability in two siblings.

    PubMed

    Cavalari, Rachel N S; Donovick, Peter J

    2015-02-01

    Agenesis of the corpus callosum (AgCC) is a congenital disorder that disrupts the development of neurological structures connecting the right and left hemispheres of the brain. In addition to neurological symptoms, many individuals with AgCC demonstrate marked deficits in social, communication, and adaptive skills. This paper presents two case studies of congenital AgCC in siblings with socioemotional and behavioral symptoms consistent with developmental disability, but with notably different symptom presentations and clinical needs. Conclusions from these cases suggest that unique symptom profiles of individuals with AgCC warrant careful consideration for referral to appropriate academic and habilitative services. PMID:24417213

  17. Gender-based differences in the shape of the human corpus callosum are associated with allometric variations

    PubMed Central

    Bruner, Emiliano; de la Cuétara, José Manuel; Colom, Roberto; Martin-Loeches, Manuel

    2012-01-01

    The corpus callosum displays considerable morphological variability between individuals. Although some characteristics are thought to differ between male and female brains, there is no agreement regarding the source of this variation. Biomedical imaging and geometric morphometrics have provided tools to investigate shape and size variation in terms of integration and correlation. Here we analyze variations at the midsagittal outline of the corpus callosum in a sample of 102 young adults in order to describe and quantify the pattern of covariation associated with its morphology. Our results suggest that the shape of the corpus callosum is characterized by low levels of morphological integration, which explains the large variability. In larger brains, a minor allometric component involves a relative reduction of the splenium. Small differences between males and?females are associated with this allometric pattern, induced primarily by size variation rather than gender-specific characteristics. PMID:22296183

  18. Gender-based differences in the shape of the human corpus callosum are associated with allometric variations.

    PubMed

    Bruner, Emiliano; de la Cuétara, José Manuel; Colom, Roberto; Martin-Loeches, Manuel

    2012-04-01

    The corpus callosum displays considerable morphological variability between individuals. Although some characteristics are thought to differ between male and female brains, there is no agreement regarding the source of this variation. Biomedical imaging and geometric morphometrics have provided tools to investigate shape and size variation in terms of integration and correlation. Here we analyze variations at the midsagittal outline of the corpus callosum in a sample of 102 young adults in order to describe and quantify the pattern of covariation associated with its morphology. Our results suggest that the shape of the corpus callosum is characterized by low levels of morphological integration, which explains the large variability. In larger brains, a minor allometric component involves a relative reduction of the splenium. Small differences between males and?females are associated with this allometric pattern, induced primarily by size variation rather than gender-specific characteristics. PMID:22296183

  19. Msh2 deficiency leads to dysmyelination of the corpus callosum, impaired locomotion, and altered sensory function in mice

    PubMed Central

    Diouf, Barthelemy; Devaraju, Prakash; Janke, Laura J.; Fan, Yiping; Frase, Sharon; Eddins, Donnie; Peters, Jennifer L.; Kim, Jieun; Pei, Deqing; Cheng, Cheng; Zakharenko, Stanislav S.; Evans, William E.

    2016-01-01

    A feature in patients with constitutional DNA-mismatch repair deficiency is agenesis of the corpus callosum, the cause of which has not been established. Here we report a previously unrecognized consequence of deficiency in MSH2, a protein known primarily for its function in correcting nucleotide mismatches or insertions and deletions in duplex DNA caused by errors in DNA replication or recombination. We documented that Msh2 deficiency causes dysmyelination of the axonal projections in the corpus callosum. Evoked action potentials in the myelinated corpus callosum projections of Msh2-null mice were smaller than wild-type mice, whereas unmyelinated axons showed no difference. Msh2-null mice were also impaired in locomotive activity and had an abnormal response to heat. These findings reveal a novel pathogenic consequence of MSH2 deficiency, providing a new mechanistic hint to previously recognized neurological disorders in patients with inherited DNA-mismatch repair deficiency. PMID:27476972

  20. Transient lesion in the splenium of the corpus callosum due to rotavirus infection.

    PubMed

    Mazur-Melewska, Katarzyna; Jonczyk-Potoczna, Katarzyna; Szpura, Krystyna; Biegański, Grzegorz; Mania, Anna; Kemnitz, Paweł; Służewski, Wojciech; Figlerowicz, Magdalena

    2015-06-01

    Transient signal changes in magnetic resonance imaging (MRI) of the splenium of the corpus callosum (SCC) can result from many different reasons, including encephalitis and encephalopathy caused by infection, seizures, metabolic disorders and asphyxia. We report a case of a 6-year-old Polish girl with rotavirus infection demonstrating a reversible SCC lesion on diffusion-weighted MRI images. She presented six episodes of generalized tonic seizures with mild acute gastroenteritis. Stool test for rotavirus antigen was positive. At the time of admission imaging showed the hyperintense region in T2-weighted and fluid-attenuated inversion-recovery MRI, a well-defined lesion in the splenium of the corpus callosum with restricted diffusion in diffusion-weighted MRI and no enhancement in post contrast T1-weighted imaging. Her first EEG showed slow brain activity in the posterior occipitotemporal portion, consisting mainly of theta waves with a frequency of 4.5-5.5 Hz and amplitude of 40 uV. The lesion had completely disappeared on follow-up MRI 10 days later. The patient recovered fully without any sequelae. PMID:25686898

  1. Shape analysis of corpus callosum in autism subtype using planar conformal mapping

    NASA Astrophysics Data System (ADS)

    He, Qing; Duan, Ye; Yin, Xiaotian; Gu, Xianfeng; Karsch, Kevin; Miles, Judith

    2009-02-01

    A number of studies have documented that autism has a neurobiological basis, but the anatomical extent of these neurobiological abnormalities is largely unknown. In this study, we aimed at analyzing highly localized shape abnormalities of the corpus callosum in a homogeneous group of autism children. Thirty patients with essential autism and twenty-four controls participated in this study. 2D contours of the corpus callosum were extracted from MR images by a semiautomatic segmentation method, and the 3D model was constructed by stacking the contours. The resulting 3D model had two openings at the ends, thus a new conformal parameterization for high genus surfaces was applied in our shape analysis work, which mapped each surface onto a planar domain. Surface matching among different individual meshes was achieved by re-triangulating each mesh according to a template surface. Statistical shape analysis was used to compare the 3D shapes point by point between patients with autism and their controls. The results revealed significant abnormalities in the anterior most and anterior body in essential autism group.

  2. Ontophyletics of the nervous system: development of the corpus callosum and evolution of axon tracts.

    PubMed Central

    Katz, M J; Lasek, R J; Silver, J

    1983-01-01

    The evolution of nervous systems has included significant changes in the axon tracts of the central nervous system. These evolutionary changes required changes in axonal growth in embryos. During development, many axons reach their targets by following guidance cues that are organized as pathways in the embryonic substrate, and the overall pattern of the major axon tracts in the adult can be traced back to the fundamental pattern of such substrate pathways. Embryological and comparative anatomical studies suggest that most axon tracts, such as the anterior commissure, have evolved by the modified use of preexisting substrate pathways. On the other hand, recent developmental studies suggest that a few entirely new substrate pathways have arisen during evolution; these apparently provided opportunities for the formation of completely new axon tracts. The corpus callosum, which is found only in placental mammals, may be such a truly new axon tract. We propose that the evolution of the corpus callosum is founded on the emergence of a new preaxonal substrate pathway, the "glial sling," which bridges the two halves of the embryonic forebrain only in placental mammals. Images PMID:6577462

  3. Bimanual coordination in alcohol-exposed children: role of the corpus callosum.

    PubMed

    Roebuck-Spencer, Tresa M; Mattson, Sarah N; Marion, Sarah Deboard; Brown, Warren S; Riley, Edward P

    2004-07-01

    The corpus callosum (CC) is one of several brain structures affected in children prenatally exposed to alcohol. This structure plays a major role in coordinating motor activity from opposite sides of the body, and deficits in bimanual coordination have been documented in individuals with agenesis of or damage to the CC, particularly when the task is performed without visual feedback. The Bimanual Coordination Test was used to assess speed and accuracy on a task where both hands must coordinate to guide a cursor through angled pathways providing measures of interhemispheric interaction or the ability of the two hemispheres to coordinate activity via the corpus callosum. Twenty-one children with fetal alcohol spectrum disorders (FASD) and 17 non-exposed control children (CON), matched closely in age, sex, and ethnicity were tested. For trials with visual feedback (WV), children with FASD were slower than CON children but were equally accurate. Although statistically significant group differences were not observed on most trials completed without visual feedback (WOV), accuracy of the FASD group on WOV trials was highly variable. Group differences in accuracy on WOV angles approached significance after accounting for performance on the WV angles, and children with FASD were significantly less accurate on an individual angle believed to be particularly sensitive to interhemispheric interaction. These results indicate that children with FASD are slower than CON children but equally accurate on basic visuomotor tasks. However, as task complexity and reliance on interhemispheric interaction increases, children with FASD demonstrate variable and inaccurate performance. PMID:15327732

  4. fMRI and corpus callosum relationships in monozygotic twins discordant for handedness.

    PubMed

    Gurd, J M; Cowell, P E; Lux, S; Rezai, R; Cherkas, L; Ebers, G C

    2013-03-01

    To further investigate brain structure and function in 26 handedness discordant monozygotic twin pairs (MzHd), MRI and behavioural assessments were carried out. These showed significant correlation between language-specific functional laterality in inferior and middle frontal gyri, and anterior corpus callosum. Previous studies of handedness discordant monozygotic twins failed to resolve the issue concerning handedness and hemispheric laterality for language due to methodological disparities. The results would be relevant to genetic theories as well as to brain structure:function explanations. MzHd twins underwent MRI and fMRI scanning as well as behavioural assessment of motor performance and cognition. There were significant differences on MRI and fMRI laterality measures, as well as a significant correlation between anterior callosal widths and functional laterality. LH twins showed higher frequencies of atypical functional laterality. There was no significant within-twin pair correlation on fMRI verbal laterality, nor did results show within-twin pair differences on verbal fluency or IQ. Implications for the field of laterality research pertain to frontal hemispheric equipotentiality for verbal processes in healthy individuals. In particular, there can be an apparent lack of cognitive 'cost' to atypical laterality. An fMRI verbal laterality index correlated significantly with corpus callosum widths near Broca's area. PMID:22527119

  5. Communicative deficits in agenesis of the corpus callosum: nonliteral language and affective prosody.

    PubMed

    Paul, Lynn K; Van Lancker-Sidtis, Diana; Schieffer, Beatrix; Dietrich, Rosalind; Brown, Warren S

    2003-05-01

    While some individuals with agenesis of the corpus callosum can perform normally on standardized intelligence tests, clinical observations suggest that they nevertheless have deficits in the domains of fluid and social intelligence. Particularly important for social competence is adequate understanding and use of paralinguistic information. This study examined the impact of callosal absence on the processing of pragmatic and paralinguistic information. Young adult males with agenesis of the corpus callosum (ACC) were evaluated in the areas of nonliteral language comprehension, proverb recognition and interpretation, and perception of affective prosody. Ten ACC individuals with normal Wechsler IQ were compared to 14 sex, age, and IQ matched normal controls. The Formulaic and Novel Language Comprehension Test (FANL-C), Gorham Proverbs Test, and LA Prosody Test were administered. ACC subjects exhibited significant impairment on the nonliteral items of the FANL-C, but no significant difference from controls in comprehension of literal items. ACC subjects also exhibited significant deficits in both self-generated interpretation and recognition of proverb meaning, and in recognition of affective prosody. These results demonstrate that normally intelligent individuals with ACC are impaired in the understanding of nonliteral language and emotional-prosodic cues that are important in social communication. In all three tests, the performance of individuals with ACC was similar to patients with right hemisphere brain damage. Thus, persons with ACC appear to lack interhemispheric integration of critical aspects of language processed by the right hemisphere. PMID:12735947

  6. A familial 7q36.3 duplication associated with agenesis of the corpus callosum.

    PubMed

    Wong, Keith; Moldrich, Randal; Hunter, Matthew; Edwards, Matthew; Finlay, David; O'Donnell, Sheridan; MacDougall, Tom; Bain, Nicole; Kamien, Benjamin

    2015-09-01

    Small chromosomal duplications involving 7q36.3 have rarely been reported. This clinical report describes four individuals from a three-generation family with agenesis of the corpus callosum (ACC) and a 0.73 Mb duplication of 7q36.3 detected by array CGH. The 7q36.3 duplication involves two genes: RNA Binding Motif Protein 33 (RBM33) and Sonic Hedgehog (SHH). Most affected family members had mild intellectual disability or borderline intellectual functioning, macrocephaly, a broad forehead, and widely spaced eyes. Two individuals had a Chiari type I malformation. This is the first family reported with ACC associated with a small duplication of these genes. While we cannot establish causation for the relationship between any single gene and the ACC in this family, there is a role for SHH in the formation of the corpus callosum through correct patterning and assembly of the commissural plate, and these data concur with vertebrate studies showing that a gain of SHH expands the facial primordium. PMID:25944787

  7. MKS1 mutations cause Joubert syndrome with agenesis of the corpus callosum.

    PubMed

    Bader, Ingrid; Decker, E; Mayr, J A; Lunzer, V; Koch, J; Boltshauser, E; Sperl, W; Pietsch, P; Ertl-Wagner, B; Bolz, H; Bergmann, C; Rittinger, O

    2016-08-01

    Joubert syndrome (JS) is a clinically and genetically heterogeneous ciliopathy characterized by episodic hyperpnea and apnea, hypotonia, ataxia, cognitive impairment and ocular motor apraxia. The "molar tooth sign" is pathognomonic of this condition. Mutations in the MKS1 gene are a major cause of Meckel-Gruber syndrome (MKS), the most common form of syndromic neural tube defects, frequently resulting in perinatal lethality. We present the phenotype and genotype of a child with severe JS and agenesis of the corpus callosum (ACC). In our patient, a next generation sequencing (NGS) approach revealed the following two variants of the MKS1 gene: first, a novel missense variant [ c.240G > T (p.Trp80Cys)], which affects a residue that is evolutionarily highly conserved in mammals and ciliates; second, a 29 bp deletion in intron 15 [c.1408-35_1408-7del29], a founder mutation, which in a homozygous state constitutes the major cause of MKS in Finland. We review the MKS1-variants in all of the eleven JS patients reported to date and compare these patients to our case. To our knowledge, this is the first patient with Joubert syndrome and agenesis of the corpus callosum where a potentially causal genotype is provided. PMID:27377014

  8. Agenesis and Dysgenesis of the Corpus Callosum: Clinical, Genetic and Neuroimaging Findings in a Series of 41 Patients

    PubMed Central

    Schell-Apacik, Chayim Can; Wagner, Kristina; Bihler, Moritz; Ertl-Wagner, Birgit; Heinrich, Uwe; Klopocki, Eva; Kalscheuer, Vera M.; Muenke, Maximilian; von Voss, Hubertus

    2009-01-01

    Agenesis of the corpus callosum (ACC) is among the most frequent human brain malformations with an incidence of 0.5–70 in 10,000. It is a heterogeneous condition, for which several different genetic causes are known, for example, ACC as part of monogenic syndromes or complex chromosomal rearrangements. We systematically evaluated the data of 172 patients with documented corpus callosum abnormalities in the records, and 23 patients with chromosomal rearrangements known to be associated with corpus callosum changes. All available neuroimaging data, including CT and MRI, were re-evaluated following a standardized protocol. Whenever feasible chromosome and subtelomere analyses as well as molecular genetic testing were performed in patients with disorders of the corpus callosum in order to identify a genetic diagnosis. Our results showed that 41 patients with complete absence (agenesis of the corpus callosum—ACC) or partial absence (dysgenesis of the corpus callosum—DCC) were identified. Out of these 28 had ACC, 13 had DCC. In 11 of the 28 patients with ACC, the following diagnoses could be established: Mowat–Wilson syndrome (n = 2), Walker–Warburg syndrome (n = 1), oro-facial-digital syndrome type 1 (n = 1), and chromosomal rearrangements (n = 7), including a patient with an apparently balanced reciprocal translocation, which led to the disruption and a predicted loss of function in the FOXG1B gene. The cause of the ACC in 17 patients remained unclear. In 2 of the 13 patients with DCC, unbalanced chromosomal rearrangements could be detected (n = 2), while the cause of DCC in 11 patients remained unclear. In our series of cases a variety of genetic causes of disorders of the corpus callosum were identified with cytogenetic anomalies representing the most common underlying etiology. PMID:18792984

  9. Interaction of thiamine deficiency and voluntary alcohol consumption disrupts rat corpus callosum ultrastructure.

    PubMed

    He, Xiaohua; Sullivan, Edith V; Stankovic, Roger K; Harper, Clive G; Pfefferbaum, Adolf

    2007-10-01

    The relative roles of alcohol and thiamine deficiency in causing brain damage remain controversial in alcoholics without the Wernicke-Korsakoff syndrome. Experimental control over alcohol consumption and diet are impossible in humans but can be accomplished in animal models. This experiment was designed to differentiate the separate and combined effects on the macro- and ultrastructure of the corpus callosum of thiamine deficiency and voluntary alcohol consumption. Adult male alcohol-preferring (P) rats (9 chronically alcohol-exposed and 9 water controls) received a thiamine-deficient diet for 2 weeks. There were four groups: five rats previously exposed to alcohol were treated with pyrithiamine (a thiamine phosphorylation inhibitor); five rats never exposed to alcohol were treated with pyrithiamine; four alcohol-exposed rats were treated with thiamine; and four rats never exposed to alcohol were treated with thiamine. On day 14, thiamine was restored in all 18 rats; 2 weeks later the 10 pyrithiamine-treated rats received intraperitoneal thiamine. The rats were perfused 61 days post-pyrithiamine treatment at age 598 days. Brains were dissected and weight and volumes were calculated. Sagittal sections were stained to measure white matter structures. The corpus callosum was examined using transmission electron microscopy to determine density of myelinated fibers, fiber diameter, and myelin thickness. The corpus callosum in the alcohol/pyrithiamine group was significantly thinner, had greater fiber density, higher percentage of small fibers, and myelin thinning than in the alcohol/thiamine and water/thiamine groups. Several measures showed a graded effect, where the alcohol/pyrithiamine group had greater pathology than the water/pyrithiamine group, which had greater pathology than the two thiamine-replete groups. Across all 16 rats, thinner myelin sheaths correlated with higher percentage of small fibers. Myelin thickness and axon diameter together accounted for 71

  10. Corpus Callosum Size, Reaction Time Speed and Variability in Mild Cognitive Disorders and in a Normative Sample

    ERIC Educational Resources Information Center

    Anstey, Kaarin J.; Mack, Holly A.; Christensen, Helen; Li, Shu-Chen; Reglade-Meslin, Chantal; Maller, Jerome; Kumar, Rajeev; Dear, Keith; Easteal, Simon; Sachdev, Perminder

    2007-01-01

    Intra-individual variability in reaction time increases with age and with neurological disorders, but the neural correlates of this increased variability remain uncertain. We hypothesized that both faster mean reaction time (RT) and less intra-individual RT variability would be associated with larger corpus callosum (CC) size in older adults, and…

  11. [STRUCTURE OF HUMAN CORPUS CALLOSUM IN AFTER-DEATH STATE COMPARED TO INTRA-VITAM MRI IMAGES].

    PubMed

    Boiagina, O

    2016-05-01

    Our preliminary results suggest that the corpus callosum is composed of a certain number of stringy formations visualized on macroscopic and microscopic level that we proposed to call commissural funiculi. They are treated as subcallous units of the first order. The purpose of this research is to find out the form of the above-mentioned corpus callosum formations as being displayed on its sagittal profile as well as the extent to which they are displayed. The material used was male and female cerebrum of mature age people, who died for reasons not related to the pathology of the central nervous system. Cerebrum extracted from the skull after being washed was exposed to a two week fixation in 10% formalin solution. The sagittal plane slicer was used for brain dissection. Photo fixation of the medial surface of hemispheres was implemented with a digital camera. It was found out that the sagittal cut of the corpus callosum can be represented as a formation having segmental structure principle. Also, according to our observations, the trunk of the corpus callosum has distinct morphological features of bilateral asymmetry. PMID:27348174

  12. Cross-species and intraspecies morphometric analysis of the corpus callosum.

    PubMed

    Olivares, R; Michalland, S; Aboitiz, F

    2000-01-01

    A cross-species morphometric study of the corpus callosum was performed in the rat, rabbit, cat, dog, horse, cow and human. Across species, the results indicate a strong, although less than linear, dependency of callosal size on brain weight. This relation tends to lose significance within species. This is consistent with other morphometric studies indicating a tendency to decrease the correlations between morphometric variables in within-species analyses as compared to between-species analyses. There are species differences in the relative size of some callosal segments particularly in the posterior third, which is larger in frontally-looking species than in laterally-looking species. No sex differences in callosal size were detected in any of the species examined. These findings are discussed in the light of possible developmental and functional correlates of the variability observed. PMID:10773624

  13. EARS2 mutations cause fatal neonatal lactic acidosis, recurrent hypoglycemia and agenesis of corpus callosum.

    PubMed

    Danhauser, Katharina; Haack, Tobias B; Alhaddad, Bader; Melcher, Marlen; Seibt, Annette; Strom, Tim M; Meitinger, Thomas; Klee, Dirk; Mayatepek, Ertan; Prokisch, Holger; Distelmaier, Felix

    2016-06-01

    Mitochondrial aminoacyl tRNA synthetases are essential for organelle protein synthesis. Genetic defects affecting the function of these enzymes may cause pediatric mitochondrial disease. Here, we report on a child with fatal neonatal lactic acidosis and recurrent hypoglycemia caused by mutations in EARS2, encoding mitochondrial glutamyl-tRNA synthetase 2. Brain ultrasound revealed agenesis of corpus callosum. Studies on patient-derived skin fibroblasts showed severely decreased EARS2 protein levels, elevated reactive oxygen species (ROS) production, and altered mitochondrial morphology. Our report further illustrates the clinical spectrum of the severe neonatal-onset form of EARS2 mutations. Moreover, in this case the live-cell parameters appeared to be more sensitive to mitochondrial dysfunction compared to standard diagnostics, which indicates the potential relevance of fibroblast studies in children with mitochondrial diseases. PMID:26780086

  14. Agenesis of the corpus callosum: genetic, developmental and functional aspects of connectivity.

    PubMed

    Paul, Lynn K; Brown, Warren S; Adolphs, Ralph; Tyszka, J Michael; Richards, Linda J; Mukherjee, Pratik; Sherr, Elliott H

    2007-04-01

    Agenesis of the corpus callosum (AgCC), a failure to develop the large bundle of fibres that connect the cerebral hemispheres, occurs in 1:4000 individuals. Genetics, animal models and detailed structural neuroimaging are now providing insights into the developmental and molecular bases of AgCC. Studies using neuropsychological, electroencephalogram and functional MRI approaches are examining the resulting impairments in emotional and social functioning, and have begun to explore the functional neuroanatomy underlying impaired higher-order cognition. The study of AgCC could provide insight into the integrated cerebral functioning of healthy brains, and may offer a model for understanding certain psychiatric illnesses, such as schizophrenia and autism. PMID:17375041

  15. Loss of resting interhemispheric functional connectivity after complete section of the corpus callosum

    PubMed Central

    Johnston, James M.; Vaishnavi, S. Neil; Smyth, Matthew D.; Zhang, Dongyang; He, Biyu J.; Zempel, John M.; Shimony, Joshua S.; Snyder, Abraham Z.; Raichle, Marcus E.

    2009-01-01

    Slow (<0.1Hz), spontaneous fluctuations in the fMRI blood oxygen level-dependent (BOLD) signal have been shown to exhibit phase coherence within functionally related areas of the brain. Surprisingly, this phenomenon appears to transcend levels of consciousness. The genesis of coherent BOLD fluctuations remains to be fully explained. We present a resting state functional connectivity study of a six-year old child with radiologically normal brain imaged both before and after complete section of the corpus callosum for the treatment of intractable epilepsy. Post-operatively, there was a striking loss of interhemispheric BOLD correlations with preserved intrahemispheric correlations. These unique data provide important insights into the relationship between connectional anatomy and functional organization of the human brain. Such observations have the potential to increase our understanding of large-scale brain systems in health and disease as well as improve the treatment of neurologic disorders. PMID:18562616

  16. Enriched environment increases the myelinated nerve fibers of aged rat corpus callosum.

    PubMed

    Zhao, Yuan-Yu; Shi, Xiao-Yan; Qiu, Xuan; Lu, Wei; Yang, Shu; Li, Chen; Chen, Lin; Zhang, Lei; Cheng, Guo-Hua; Tang, Yong

    2012-06-01

    In this study, the effect of enriched environment (EE) on the spatial learning of aged rats was examined, and then the effects of EE on the aged corpus callosum (CC) were investigated by means of the modern stereological methods. We found that EE significantly improved the spatial learning of aged rats. The CC volume, the total volume of the myelinated fibers and total volume of the myelin sheaths in the CC, the total length of the myelinated fibers in the CC of enriched rats were significantly increased when compared to standard rats. The increase of the myelinated fibers in enriched rat CC might provide one of the structural bases for the enrichment-related improvement of the spatial learning. This study provided, to the best of our knowledge, the first evidence of environmental enrichment-induced increases of the CC and the myelinated fibers in the CC of aged rats. PMID:22431229

  17. Corpus Callosum Pathology as a Potential Surrogate Marker of Cognitive Impairment in Diffuse Axonal Injury.

    PubMed

    Ubukata, Shiho; Ueda, Keita; Sugihara, Genichi; Yassin, Walid; Aso, Toshihiko; Fukuyama, Hidenao; Murai, Toshiya

    2016-01-01

    Diffuse axonal injury is a major form of traumatic brain injury. Neuropsychological assessments and high-resolution structural MRI were conducted using T1-weighted and diffusion tensor imaging. This study included 10 patients with diffuse axonal injury (all men, mean age 30.8±10.5 years) and 12 age- and sex-matched normal control participants. Patients with diffuse axonal injury had widespread volume reductions and lower fractional anisotropy in the corpus callosum (CC) compared with controls. Furthermore, cognitive processing speed was associated with reductions in white matter volume and fractional anisotropy in the CC. These findings suggest that CC pathology may be a potential surrogate marker of the cognitive deficits in these patients. PMID:26569151

  18. The corpus callosum and empathy in adults with a history of preterm birth.

    PubMed

    Lawrence, E J; Allen, G M; Walshe, M; Allin, M; Murray, R; Rifkin, L; McGuire, P K; Nosarti, C

    2010-07-01

    Reduced posterior corpus callosum (CC) area has been consistently observed in children and adolescents born very preterm (VPT). CC structural differences are also observed in people diagnosed with empathy disorders. This study examined empathy in relation to CC size in VPT adults and controls. CC area was manually measured for 17 VPT adults and 9 controls. Participants completed the Interpersonal Reactivity Index (Davis, 1980) and the Empathy Quotient (Baron-Cohen & Wheelwright, 2004). VPT adults had reduced posterior CC area in contrast to controls, and a positive linear trend was observed between posterior CC size and gestational age. No between-group empathy differences were observed, although self-reported personal distress in response to social situations was higher in VPT adults, and negatively associated with anterior CC area. We conclude that VPT adults have a smaller posterior CC, which is associated with gestational age, and elevated social distress, which may be mediated by anterior CC size. PMID:20441689

  19. Sudden worsening after subdural haematoma surgery: will there be a corpus callosum injury?

    PubMed Central

    Panciani, Pier Paolo; Roca, Elena; Lodoli, Giovanni; Fontanella, Marco Maria

    2014-01-01

    We report a case of mild encephalopathy with a reversible splenial lesion (MERS) which occurred after chronic subdural haematoma (CSDH) surgery. The patient was admitted to our hospital for drowsiness and marked asthenia. The cerebral CT scan revealed a CSDH and surgery allowed to improve the symptoms, but after several days we observed a sudden worsening. The patient developed left-sided myoclonic seizures followed by left hemiplegia and worsening drowsiness. Electrolytes imbalance and inflammatory causes were excluded. The CT scan showed a right cerebral swelling and the subsequent MRI revealed a single lesion in the splenium of the corpus callosum, hyperintense on diffusion-weighted images. After osmotic therapy the patient improved and on day 10 of admission the MRI showed a complete resolution of the lesion. This is the first report that described an association between CSDH and MERS. Possible aetiopathogenetic mechanisms are discussed. PMID:24862419

  20. Pre- and Postnatal Analysis of Chromosome 1q44 Deletion in Agenesis of Corpus Callosum

    PubMed Central

    Shetty, Mitesh; Srikanth, Ambika; Kadandale, Jayarama; Hegde, Sridevi

    2015-01-01

    Agenesis of corpus callosum (ACC) is one of the common brain abnormalities and also a common finding in children with mental disability. ACC is heterogeneous and can occur as an isolated condition or as part of a syndrome. ACC can be accurately identified by the absence of the cavum septum pallucidum and tear drop effect of the lateral ventricle after 18 weeks of pregnancy in an ultrasound scan. Genetic causes have been attributed to 30-45% of cases with ACC. Submicroscopic deletions of 1q43q44 have been reported in several cases of ACC. The AKT3 gene, mapped to 1q44, is required for the development of the callosum and brain size. It is considered to be a candidate gene for ACC. We studied a total of 22 cases with ACC, in pre- and postnatal samples using FISH probes. None of the samples showed a deletion in 1q44, implying that the AKT3 gene may not be associated with ACC. PMID:26648835

  1. Learning and memory in individuals with agenesis of the corpus callosum.

    PubMed

    Paul, Lynn K; Erickson, Roger L; Hartman, Jo Ann; Brown, Warren S

    2016-06-01

    Damage to long white matter pathways in the cerebral cortex is known to affect memory capacity. However, the specific contribution of interhemispheric connectivity in memory functioning is only beginning to become understood. The present study examined verbal and visual memory processing in individuals with agenesis of the corpus callosum (AgCC) using the Wechsler Memory Scale-Third Edition (WMS-III; Wechsler, 1997b). Thirty participants with AgCC (FSIQ >78) were compared against 30 healthy age and IQ matched controls on auditory/verbal (Logical Memory, Verbal Paired Associates) and visual (Visual Reproduction, Faces) memory subtests. Performance was worse in AgCC than controls on immediate and delayed verbal recall for rote word pairs and on delayed recall of faces, as well as on percent recall for these tasks. Immediate recall for thematic information from stories was also worse in AgCC, but groups did not differ on memory for details from narratives or on recall for thematic information following a time delay. Groups also did not differ on memory for abstract figures or immediate recall of faces. On all subtests, individuals with AgCC had greater frequency of clinically significant impairments than predicted by the normal distribution. Results suggest less efficient overall verbal and visual learning and memory with relative weaknesses processing verbal pairs and delayed recall for faces. These findings suggest that the corpus callosum facilitates more efficient learning and recall for both verbal and visual information, that individuals with AgCC may benefit from receiving verbal information within semantic context, and that known deficits in facial processing in individuals with AgCC may contribute to their impairments in recall for faces. PMID:27091586

  2. Behavioral effects of corpus callosum transection and environmental enrichment in adult rats.

    PubMed

    Miu, Andrei C; Heilman, Renata M; Paşca, Sergiu P; Stefan, Catrinel A; Spânu, Florina; Vasiu, Renata; Olteanu, Adrian I; Miclea, Mircea

    2006-09-15

    A common assumption about the corpus callosum transection (CCX) is that it only affects behaviors heavily relying on interhemispheric communication. However, cerebral laterality is ubiquitous across motor and perceptual, cognitive and emotional domains, and the corpus callosum is important for its establishment. Several recent studies showed that the partial denervation of the sensorimotor isocortex through CCX derepressed neural growth processes that were sensitive to motor demand (experience-dependent neural plasticity). We investigated whether the facilitatory effects of CCX on cortical neural plasticity, shaped by differential housing, extended beyond the motor domain. Adult rats were housed in enriched (EE), standard (SE) or impoverished environments (IE) for 10 weeks, that is, 2 weeks before they underwent CCX or sham surgery, and, then, 8 weeks throughout the experiments. After they recovered from surgery, the behavioral performance of rats was tested using open-field, spontaneous alternation in the T-maze, paw preference, Morris water maze, and tone fear conditioning. The results indicated that the effects of CCX and housing on open-field behavior were independent, with CCX increasing the time spent in the center of the field at the beginning of the observation (i.e., emotionality), and EE and IE increasing rearing (emotionality) and reducing teeth-chattering (habituation), respectively. CCX reduced the frequency of spontaneous alternation, denoting spatial working memory deficits, while housing did not influence this performance. Neither CCX, nor housing significantly affected paw preference lateralization, although CCX was associated with a leftward bias in paw preference. In the Morris water maze, housing had effects on spatial acquisition, while CCX reduced activity, without interfering with spatial memory. CCX did not influence tone fear conditioning, but context fear conditioning seemed to benefit from EE. We conclude that CCX in adult rats has subtle

  3. Disrupted developmental organization of the structural connectome in fetuses with corpus callosum agenesis.

    PubMed

    Jakab, András; Kasprian, Gregor; Schwartz, Ernst; Gruber, Gerlinde Maria; Mitter, Christian; Prayer, Daniela; Schöpf, Veronika; Langs, Georg

    2015-05-01

    Agenesis of the corpus callosum is a model disease for disrupted connectivity of the human brain, in which the pathological formation of interhemispheric fibers results in subtle to severe cognitive deficits. Postnatal studies suggest that the characteristic abnormal pathways in this pathology are compensatory structures that emerge via neural plasticity. We challenge this hypothesis and assume a globally different network organization of the structural interconnections already in the fetal acallosal brain. Twenty fetuses with isolated corpus callosum agenesis with or without associated malformations were enrolled and fiber connectivity among 90 brain regions was assessed using in utero diffusion tensor imaging and streamline tractography. Macroscopic scale connectomes were compared to 20 gestational age-matched normally developing fetuses with multiple granularity of network analysis. Gradually increasing connectivity strength and tract diffusion anisotropy during gestation were dominant in antero-posteriorly running paramedian and antero-laterally running aberrant pathways, and in short-range connections in the temporoparietal regions. In fetuses with associated abnormalities, more diffuse reduction of cortico-cortical and cortico-subcortical connectivity was observed than in cases with isolated callosal agenesis. The global organization of anatomical networks consisted of less segregated nodes in acallosal brains, and hubs of dense connectivity, such as the thalamus and cingulate cortex, showed reduced network centrality. Acallosal fetal brains show a globally altered connectivity network structure compared to normals. Besides the previously described Probst and sigmoid bundles, we revealed a prenatally differently organized macroconnectome, dominated by increased connectivity. These findings provide evidence that abnormal pathways are already present during at early stages of fetal brain development in the majority of cerebral white matter. PMID:25725467

  4. A framework for the automatic detection and characterization of brain malformations: Validation on the corpus callosum.

    PubMed

    Peruzzo, Denis; Arrigoni, Filippo; Triulzi, Fabio; Righini, Andrea; Parazzini, Cecilia; Castellani, Umberto

    2016-08-01

    In this paper, we extend the one-class Support Vector Machine (SVM) and the regularized discriminative direction analysis to the Multiple Kernel (MK) framework, providing an effective analysis pipeline for the detection and characterization of brain malformations, in particular those affecting the corpus callosum. The detection of the brain malformations is currently performed by visual inspection of MRI images, making the diagnostic process sensible to the operator experience and subjectiveness. The method we propose addresses these problems by automatically reproducing the neuroradiologist's approach. One-class SVMs are appropriate to cope with heterogeneous brain abnormalities that are considered outliers. The MK framework allows to efficiently combine the different geometric features that can be used to describe brain structures. Moreover, the regularized discriminative direction analysis is exploited to highlight the specific malformative patterns for each patient. We performed two different experiments. Firstly, we tested the proposed method to detect the malformations of the corpus callosum on a 104 subject dataset. Results showed that the proposed pipeline can classify the subjects with an accuracy larger than 90% and that the discriminative direction analysis can highlight a wide range of malformative patterns (e.g., local, diffuse, and complex abnormalities). Secondly, we compared the diagnosis of four neuroradiologists on a dataset of 128 subjects. The diagnosis was performed both in blind condition and using the classifier and the discriminative direction outputs. Results showed that the use of the proposed pipeline as an assisted diagnosis tool improves the inter-subject variability of the diagnosis. Finally, a graphical representation of the discriminative direction analysis was proposed to enhance the interpretability of the results and provide the neuroradiologist with a tool to fully and clearly characterize the patient malformations at single

  5. Mobility decline in the elderly relates to lesion accrual in the splenium of the corpus callosum.

    PubMed

    Moscufo, Nicola; Wolfson, Leslie; Meier, Dominik; Liguori, Maria; Hildenbrand, Peter G; Wakefield, Dorothy; Schmidt, Julia A; Pearlson, Godfrey D; Guttmann, Charles R G

    2012-04-01

    In a previous cross-sectional study on baseline data, we demonstrated that the volume of brain white matter hyperintensities (WMH) in the splenium of corpus callosum (SCC) predicted the current mobility function of older persons. The primary aim of this follow-up study was to determine the relation of WMH volume change in SCC (SCC-∆WMH) with change in mobility measures. A secondary aim was to characterize the global and regional progression of WMH. Mobility function and WMH burden were evaluated at baseline and at 2 years in 77 community-dwelling individuals (baseline age, 82 ± 4). Regional WMH in SCC, as well as genu and body of corpus callosum, subregions of corona radiata, and superior longitudinal fasciculus were determined using a white matter parcellation atlas. The total WMH volume increased 3.3 ± 3.5 ml/year, mainly through enlargement. Significant WMH increases were observed in all selected regions, particularly within the corona radiata. While at baseline and follow-up we observed correlations between WMH burden and several measures of mobility, longitudinal change correlated only with change in chair rise (CR). SCC-∆WMH showed the highest correlation (r = -0.413, p = 0.0002) and was the best regional predictor of CR decline (OR = 1.5, r(2) = 0.3). The SCC-∆WMH was more than five times larger in the CR-decline group compared to the no-decline group (p = 0.0003). The SCC-∆WMH (top quartile) showed a higher sensitivity/specificity for CR decline compared to change in total WMH, 63/88% versus 52/84%, respectively. The findings suggest that accrual of WMHs in posterior areas of the brain supporting inter-hemispheric integration and processing of visual-spatial information is a mechanism contributing to age-related mobility deterioration. PMID:21505765

  6. PEG-PDLLA Micelle Treatment Improves Axonal Function of the Corpus Callosum following Traumatic Brain Injury

    PubMed Central

    Ping, Xingjie; Jiang, Kewen; Lee, Seung-Young; Cheng, Ji-Xing

    2014-01-01

    Abstract The initial pathological changes of diffuse axonal injury following traumatic brain injury (TBI) include membrane disruption and loss of ionic homeostasis, which further lead to dysfunction of axonal conduction and axon disconnection. Resealing the axolemma is therefore a potential therapeutic strategy for the early treatment of TBI. Monomethoxy poly (ethylene glycol)-poly (D, L–lactic acid) di-block copolymer micelles (mPEG-PDLLA) have been shown to restore depressed compound action potentials (CAPs) of spinal axons and promote functional recovery after spinal cord injury. Here, we evaluate the effect of the micelles on repairing the injured cortical axons following TBI. Adult mice subjected to controlled cortical impact (CCI) were treated with intravenous injection of the micelles at 0 h or 4 h after injury. Evoked CAPs were recorded from the corpus callosum of coronal cortical slices at 2 days after injury. The CCI caused significant decreases in the amplitudes of two CAP peaks that were respectively generated by the faster myelinated axons and slower unmyelinated axons. Micelle treatment at both 0 h and 4 h after CCI resulted in significant increases in both CAP peak amplitudes. Injection of fluorescent dye-labeled micelles revealed high fluorescent staining in cortical gray and white matters underneath the impact site. Labeling membrane-perforated neurons by injecting a membrane impermeable dye Texas Red-labeled dextran into lateral ventricles at 2 h post-CCI revealed that immediate micelle injection after CCI did not reduce the number of dye-stained cortical neurons and dentate granule cells of the hippocampus, indicating its ineffectiveness in repairing plasma membrane of neuronal somata. We conclude that intravenous administration of mPEG-PDLLA micelles immediately or at 4 h after TBI allows brain penetration via the compromised blood brain–barrier, and thereby improves the function of both myelinated and unmyelinated axons of the

  7. Oligodendrocytes in mouse corpus callosum are coupled via gap junction channels formed by connexin47 and connexin32.

    PubMed

    Maglione, Marta; Tress, Oliver; Haas, Brigitte; Karram, Khalad; Trotter, Jacqueline; Willecke, Klaus; Kettenmann, Helmut

    2010-07-01

    According to previously published ultrastructural studies, oligodendrocytes in white matter exhibit gap junctions with astrocytes, but not among each other, while in vitro oligodendrocytes form functional gap junctions. We have studied functional coupling among oligodendrocytes in acute slices of postnatal mouse corpus callosum. By whole-cell patch clamp we dialyzed oligodendrocytes with biocytin, a gap junction-permeable tracer. On average 61 cells were positive for biocytin detected by labeling with streptavidin-Cy3. About 77% of the coupled cells stained positively for the oligodendrocyte marker protein CNPase, 9% for the astrocyte marker GFAP and 14% were negative for both CNPase and GFAP. In the latter population, the majority expressed Olig2 and some NG2, markers for oligodendrocyte precursors. Oligodendrocytes are known to express Cx47, Cx32 and Cx29, astrocytes Cx43 and Cx30. In Cx47-deficient mice, the number of coupled cells was reduced by 80%. Deletion of Cx32 or Cx29 alone did not significantly reduce the number of coupled cells, but coupling was absent in Cx32/Cx47-double-deficient mice. Cx47-ablation completely abolished coupling of oligodendrocytes to astrocytes. In Cx43-deficient animals, oligodendrocyte-astrocyte coupling was still present, but coupling to oligodendrocyte precursors was not observed. In Cx43/Cx30-double deficient mice, oligodendrocyte-to-astrocyte coupling was almost absent. Uncoupled oligodendrocytes showed a higher input resistance. We conclude that oligodendrocytes in white matter form a functional syncytium predominantly among each other dependent on Cx47 and Cx32 expression, while astrocytic connexins expression can promote the size of this network. PMID:20468052

  8. Truncated Cables1 causes agenesis of the corpus callosum in mice.

    PubMed

    Mizuno, Seiya; Tra, Dinh T H; Mizobuchi, Atsushi; Iseki, Hiroyoshi; Mizuno-Iijima, Saori; Kim, Jun-Dal; Ishida, Junji; Matsuda, Yoichi; Kunita, Satoshi; Fukamizu, Akiyoshi; Sugiyama, Fumihiro; Yagami, Ken-ichi

    2014-03-01

    Agenesis of the corpus callosum (ACC) is a congenital abnormality of the brain structure. More than 60 genes are known to be involved in corpus callosum development. However, the molecular mechanisms underlying ACC are not fully understood. Previously, we produced a novel transgenic mouse strain, TAS, carrying genes of the tetracycline-inducible expression system that are not involved in brain development, and inherited ACC was observed in the brains of all homozygous TAS mice. Although ACC was probably induced by transgene insertion mutation, the causative gene and the molecular mechanism of its pathogenesis remain unclear. Here, we first performed interphase three-color fluorescence in situ hybridization (FISH) analysis to determine the genomic insertion site. Transgenes were inserted into chromosome 18 ∼12.0 Mb from the centromere. Gene expression analysis and genomic PCR walking showed that the genomic region containing exon 4 of Cables1 was deleted by transgene insertion and the other exons of Cables1 were intact. The mutant allele was designated as Cables1(TAS). Interestingly, Cables1(TAS) mRNA consisted of exons 1-3 of Cables1 and part of the transgene that encoded a novel truncated Cables1 protein. Homozygous TAS mice exhibited mRNA expression of Cables1(TAS) in the fetal cerebrum, but not that of wild-type Cables1. To investigate whether a dominant negative effect of Cables1(TAS) or complete loss of function of Cables1 gives rise to ACC, we produced Cables1-null mutant mice. ACC was not observed in Cables1-null mutant mice, suggesting that a dominant negative effect of Cables1(TAS) impairs callosal formation. Moreover, ACC frequency in Cables1(+/TAS) mice was significantly lower than that in Cables1(-/TAS) mice, indicating that wild-type Cables1 interfered with the dominant negative effect of Cables1(TAS). This study indicated that truncated Cables1 causes ACC and wild-type Cables1 contributes to callosal formation. PMID:24336072

  9. Effects of Severing the Corpus Callosum on Electrical and BOLD Functional Connectivity and Spontaneous Dynamic Activity in the Rat Brain

    PubMed Central

    Magnuson, Matthew E.; Thompson, Garth J.; Pan, Wen-Ju

    2014-01-01

    Abstract Functional networks, defined by synchronous spontaneous blood oxygenation level-dependent (BOLD) oscillations between spatially distinct brain regions, appear to be essential to brain function and have been implicated in disease states, cognitive capacity, and sensing and motor processes. While the topographical extent and behavioral function of these networks has been extensively investigated, the neural functions that create and maintain these synchronizations remain mysterious. In this work callosotomized rodents are examined, providing a unique platform for evaluating the influence of structural connectivity via the corpus callosum on bilateral resting state functional connectivity. Two experimental groups were assessed, a full callosotomy group, in which the corpus callosum was completely sectioned, and a sham callosotomy group, in which the gray matter was sectioned but the corpus callosum remained intact. Results indicated a significant reduction in interhemispheric connectivity in the full callosotomy group as compared with the sham group in primary somatosensory cortex and caudate-putamen regions. Similarly, electrophysiology revealed significantly reduced bilateral correlation in band limited power. Bilateral gamma Band-limited power connectivity was most strongly affected by the full callosotomy procedure. This work represents a robust finding indicating the corpus callosum's influence on maintaining integrity in bilateral functional networks; further, functional magnetic resonance imaging (fMRI) and electrophysiological connectivity share a similar decrease in connectivity as a result of the callosotomy, suggesting that fMRI-measured functional connectivity reflects underlying changes in large-scale coordinated electrical activity. Finally, spatiotemporal dynamic patterns were evaluated in both groups; the full callosotomy rodents displayed a striking loss of bilaterally synchronous propagating waves of cortical activity. PMID:24117343

  10. Diffusion tensor imaging and myelin composition analysis reveal abnormal myelination in corpus callosum of canine mucopolysaccharidosis I.

    PubMed

    Provenzale, James M; Nestrasil, Igor; Chen, Steven; Kan, Shih-Hsin; Le, Steven Q; Jens, Jacqueline K; Snella, Elizabeth M; Vondrak, Kristen N; Yee, Jennifer K; Vite, Charles H; Elashoff, David; Duan, Lewei; Wang, Raymond Y; Ellinwood, N Matthew; Guzman, Miguel A; Shapiro, Elsa G; Dickson, Patricia I

    2015-11-01

    Children with mucopolysaccharidosis I (MPS I) develop hyperintense white matter foci on T2-weighted brain magnetic resonance (MR) imaging that are associated clinically with cognitive impairment. We report here a diffusion tensor imaging (DTI) and tissue evaluation of white matter in a canine model of MPS I. We found that two DTI parameters, fractional anisotropy (a measure of white matter integrity) and radial diffusivity (which reflects degree of myelination) were abnormal in the corpus callosum of MPS I dogs compared to carrier controls. Tissue studies of the corpus callosum showed reduced expression of myelin-related genes and an abnormal composition of myelin in MPS I dogs. We treated MPS I dogs with recombinant alpha-L-iduronidase, which is the enzyme that is deficient in MPS I disease. The recombinant alpha-L-iduronidase was administered by intrathecal injection into the cisterna magna. Treated dogs showed partial correction of corpus callosum myelination. Our findings suggest that abnormal myelination occurs in the canine MPS I brain, that it may underlie clinically-relevant brain imaging findings in human MPS I patients, and that it may respond to treatment. PMID:26222335

  11. Age-Associated Alterations in Corpus Callosum White Matter Integrity in Bipolar Disorder Assessed Using Probabilistic Tractography

    PubMed Central

    Toteja, Nitin; Cokol, Perihan Guvenek; Ikuta, Toshikazu; Kafantaris, Vivian; Peters, Bart D.; Burdick, Katherine E.; John, Majnu; Malhotra, Anil K.; Szeszko, Philip R.

    2014-01-01

    Objectives Atypical age-associated changes in white matter integrity may play a role in the neurobiology of bipolar disorder, but no studies have examined the major white matter tracts using nonlinear statistical modeling across a wide age range in this disorder. The goal of this study was to identify possible deviations in the typical pattern of age-associated changes in white matter integrity in patients with bipolar disorder across the age range of 9 to 62 years. Methods Diffusion tensor imaging was performed in 57 (20M/37F) patients with a diagnosis of bipolar disorder and 57 (20M/37F) age- and sex-matched healthy volunteers. Mean diffusivity and fractional anisotropy were computed for the genu and splenium of the corpus callosum, two projection tracts, and five association tracts using probabilistic tractography. Results Overall, patients had lower fractional anisotropy and higher mean diffusivity compared to healthy volunteers across all tracts (while controlling for the effects of age and age2). In addition, there were greater age-associated increases in mean diffusivity in patients compared to healthy volunteers within the genu and splenium of the corpus callosum beginning in the second and third decades of life. Conclusions Our findings provide evidence for alterations in the typical pattern of white matter development in patients with bipolar disorder compared to healthy volunteers. Changes in white matter development within the corpus callosum may lead to altered inter-hemispheric communication that is considered integral to the neurobiology of the disorder. PMID:25532972

  12. Functional Topography of Human Corpus Callosum: An fMRI Mapping Study

    PubMed Central

    Fabri, Mara; Polonara, Gabriele

    2013-01-01

    The concept of a topographical map of the corpus callosum (CC) has emerged from human lesion studies and from electrophysiological and anatomical tracing investigations in other mammals. Over the last few years a rising number of researchers have been reporting functional magnetic resonance imaging (fMRI) activation in white matter, particularly the CC. In this study the scope for describing CC topography with fMRI was explored by evoking activation through simple sensory stimulation and motor tasks. We reviewed our published and unpublished fMRI and diffusion tensor imaging data on the cortical representation of tactile, gustatory, auditory, and visual sensitivity and of motor activation, obtained in 36 normal volunteers and in 6 patients with partial callosotomy. Activation foci were consistently detected in discrete CC regions: anterior (taste stimuli), central (motor tasks), central and posterior (tactile stimuli), and splenium (auditory and visual stimuli). Reconstruction of callosal fibers connecting activated primary gustatory, motor, somatosensory, auditory, and visual cortices by diffusion tensor tracking showed bundles crossing, respectively, through the genu, anterior and posterior body, and splenium, at sites harboring fMRI foci. These data confirm that the CC commissure has a topographical organization and demonstrate that its functional topography can be explored with fMRI. PMID:23476810

  13. Bimanual motor deficits in older adults predicted by diffusion tensor imaging metrics of corpus callosum subregions.

    PubMed

    Serbruyns, L; Gooijers, J; Caeyenberghs, K; Meesen, R L; Cuypers, K; Sisti, H M; Leemans, A; Swinnen, Stephan P

    2015-01-01

    Age-related changes in the microstructural organization of the corpus callosum (CC) may explain declines in bimanual motor performance associated with normal aging. We used diffusion tensor imaging in young (n = 33) and older (n = 33) adults to investigate the microstructural organization of seven specific CC subregions (prefrontal, premotor, primary motor, primary sensory, parietal, temporal and occipital). A set of bimanual tasks was used to assess various aspects of bimanual motor functioning: the Purdue Pegboard test, simultaneous and alternating finger tapping, a choice reaction time test and a complex visuomotor tracking task. The older adults showed age-related deficits on all measures of bimanual motor performance. Correlation analyses within the older group showed that white matter fractional anisotropy of the CC occipital region was associated with bimanual fine manipulation skills (Purdue Pegboard test), whereas better performance on the other bimanual tasks was related to higher fractional anisotropy in the more anterior premotor, primary motor and primary sensory CC subregions. Such associations were less prominent in the younger group. Our findings suggest that structural alterations of subregional callosal fibers may account for bimanual motor declines in normal aging. PMID:24158531

  14. Structural and functional brain rewiring clarifies preserved interhemispheric transfer in humans born without the corpus callosum

    PubMed Central

    Tovar-Moll, Fernanda; Monteiro, Myriam; Andrade, Juliana; Bramati, Ivanei E.; Vianna-Barbosa, Rodrigo; Marins, Theo; Rodrigues, Erika; Dantas, Natalia; Behrens, Timothy E. J.; de Oliveira-Souza, Ricardo; Moll, Jorge; Lent, Roberto

    2014-01-01

    Why do humans born without the corpus callosum, the major interhemispheric commissure, lack the disconnection syndrome classically described in callosotomized patients? This paradox was discovered by Nobel laureate Roger Sperry in 1968, and has remained unsolved since then. To tackle the hypothesis that alternative neural pathways could explain this puzzle, we investigated patients with callosal dysgenesis using structural and functional neuroimaging, as well as neuropsychological assessments. We identified two anomalous white-matter tracts by deterministic and probabilistic tractography, and provide supporting resting-state functional neuroimaging and neuropsychological evidence for their functional role in preserved interhemispheric transfer of complex tactile information, such as object recognition. These compensatory pathways connect the homotopic posterior parietal cortical areas (Brodmann areas 39 and surroundings) via the posterior and anterior commissures. We propose that anomalous brain circuitry of callosal dysgenesis is determined by long-distance plasticity, a set of hardware changes occurring in the developing brain after pathological interference. So far unknown, these pathological changes somehow divert growing axons away from the dorsal midline, creating alternative tracts through the ventral forebrain and the dorsal midbrain midline, with partial compensatory effects to the interhemispheric transfer of cortical function. PMID:24821757

  15. Dehydration-Induced Anorexia Reduces Astrocyte Density in the Rat Corpus Callosum.

    PubMed

    Reyes-Haro, Daniel; Labrada-Moncada, Francisco Emmanuel; Miledi, Ricardo; Martínez-Torres, Ataúlfo

    2015-01-01

    Anorexia nervosa is an eating disorder associated with severe weight loss as a consequence of voluntary food intake avoidance. Animal models such as dehydration-induced anorexia (DIA) mimic core features of the disorder, including voluntary reduction in food intake, which compromises the supply of energy to the brain. Glial cells, the major population of nerve cells in the central nervous system, play a crucial role in supplying energy to the neurons. The corpus callosum (CC) is the largest white matter tract in mammals, and more than 99% of the cell somata correspond to glial cells in rodents. Whether glial cell density is altered in anorexia is unknown. Thus, the aim of this study was to estimate glial cell density in the three main regions of the CC (genu, body, and splenium) in a murine model of DIA. The astrocyte density was significantly reduced (~34%) for the DIA group in the body of the CC, whereas in the genu and the splenium no significant changes were observed. DIA and forced food restriction (FFR) also reduced the ratio of astrocytes to glial cells by 57.5% and 22%, respectively, in the body of CC. Thus, we conclude that DIA reduces astrocyte density only in the body of the rat CC. PMID:26090235

  16. Dehydration-Induced Anorexia Reduces Astrocyte Density in the Rat Corpus Callosum

    PubMed Central

    Reyes-Haro, Daniel; Labrada-Moncada, Francisco Emmanuel; Miledi, Ricardo; Martínez-Torres, Ataúlfo

    2015-01-01

    Anorexia nervosa is an eating disorder associated with severe weight loss as a consequence of voluntary food intake avoidance. Animal models such as dehydration-induced anorexia (DIA) mimic core features of the disorder, including voluntary reduction in food intake, which compromises the supply of energy to the brain. Glial cells, the major population of nerve cells in the central nervous system, play a crucial role in supplying energy to the neurons. The corpus callosum (CC) is the largest white matter tract in mammals, and more than 99% of the cell somata correspond to glial cells in rodents. Whether glial cell density is altered in anorexia is unknown. Thus, the aim of this study was to estimate glial cell density in the three main regions of the CC (genu, body, and splenium) in a murine model of DIA. The astrocyte density was significantly reduced (~34%) for the DIA group in the body of the CC, whereas in the genu and the splenium no significant changes were observed. DIA and forced food restriction (FFR) also reduced the ratio of astrocytes to glial cells by 57.5% and 22%, respectively, in the body of CC. Thus, we conclude that DIA reduces astrocyte density only in the body of the rat CC. PMID:26090235

  17. Reduced white matter connectivity in the corpus callosum of children with Tourette syndrome

    PubMed Central

    Plessen, Kerstin J.; Grüner, Renate; Lundervold, Arvid; Hirsch, Jochen G.; Xu, Dongrong; Bansal, Ravi; Hammar, Åsa; Lundervold, Astri J.; Wentzel-Larsen, Tore; Lie, Stein Atle; Gass, Achim; Peterson, Bradley S.; Hugdahl, Kenneth

    2008-01-01

    Background Brain imaging studies have revealed anatomical anomalies in the brains of individuals with Tourette syndrome (TS). Prefrontal regions have been found to be larger and the corpus callosum (CC) area smaller in children and young adults with TS compared with healthy control subjects, and these anatomical features have been understood to reflect neural plasticity that helps to attenuate the severity of tics. Method CC white matter connectivity, as measured by the Fractional Anisotropy (FA) index from diffusion tensor images, was assessed in 20 clinically well-defined boys with Tourette syndrome and 20 age- and gender-matched controls. Results The hypothesis that children with TS would show reduced measures of connectivity in CC fibers was confirmed for all subregions of the CC. There was no significant interaction of TS and region. Reductions in FA in CC regions may reflect either fewer interhemispheric fibers or reduced axonal myelination. FA values did not correlate significantly with the severity of tic symptoms. Group differences in measures of connectivity did not seem to be attributable to the presence of comorbid ADHD or OCD, to medication exposure, or group differences in IQ. Conclusion Our findings of a reduced interhemispheral white matter connectivity add to the understanding of neural connectivity and plasticity in the brains of children who have TS. PMID:17073980

  18. Age and Sex Effects on Corpus Callosum Morphology Across the Lifespan

    PubMed Central

    Prendergast, Daniel; Ardekani, Babak; Ikuta, Toshikazu; John, Majnu; Peters, Bart; DeRosse, Pamela; Wellington, Robin; Malhotra, Anil K.; Szeszko, Philip R.

    2015-01-01

    The corpus callosum (CC) is the largest inter-hemispheric white matter tract in the human brain, and is characterized by pronounced differences in morphology among individuals. There are limited data, however, regarding typical development, sex differences, and the neuropsychological correlates of individual differences within CC subregions. Magnetic resonance (MR) imaging exams were collected in a large cohort (N = 305) of healthy individuals (ages 8 to 68). We used a highly reliable program to automatically identify the mid-sagittal plane and obtain CC subregion measures according to approaches described by Witelson (1989) and Hampel (1998) and a measure of whole CC shape (i.e., circularity). CC measurement parameters, including area, perimeter, length, circularity and CC subregion area values were generally characterized by inverted U-shaped curves across the observed age range. Peak values for CC subregions were observed between ages 32 and 45, and descriptive linear correlations were consistent with sharper area changes in development. We also observed differing age-associated changes across the lifespan between males and females in the CC subregion corresponding to the genu (Witelson’s subregion 2), as well as CC circularity. Mediation analysis using path modeling indicated that genu area mediated the relationship between age and processing speed for females, and the relationship between age and visual learning and executive functioning for males. Taken together, our findings implicate sex differences in CC morphology across the lifespan that are localized to the genu, which appear to mediate neuropsychological functions. PMID:25833103

  19. A Case of a Newborn with Agenesis of the Corpus Callosum Complicated with Ocular Albinism

    PubMed Central

    Miki, Michiko; Miyamoto, Makiko; Mitsutsuji, Tatsuma; Watanabe, Hiroko; Shimizu, Kazuhiro; Matsuo, Junko; Tonari, Masahiro; Kida, Teruyo; Sugasawa, Jun; Ikeda, Tsunehiko

    2016-01-01

    Purpose To report a case of ocular albinism found in a newborn infant in whom agenesis of the corpus callosum (ACC) was indicated in utero. Case Report This study involved a female newborn who was delivered after a gestational period of 41 weeks. The patient was referred to the Obstetrics Department at Takatsuki Hospital, Takatsuki City, Japan, after the indication of ACC by magnetic resonance imaging (MRI) at a nearby clinic during the fetal period. At birth, the baby's weight was 2,590 g, and ACC and ventricular enlargement were found by cranial sonography and cranial MRI. While initial ophthalmic findings noted partial loss of pigmentation of the iris and hypopigmentation of broad areas of the fundus in both eyes, nystagmus was not observed. The patient's hair pigment was slightly diluted, and the color of her skin was slightly off-white. At 2 years after birth, obvious mental retardation was observed. With regard to other systemic findings, no apparent heart, kidney, or immune system abnormalities were found. Conclusion Although the patient in question is presently growing without any major systemic problems, it will be necessary in the future to pay attention to any changes in systemic and ophthalmic findings. PMID:27462254

  20. Mapping corpus callosum morphology in twin pairs discordant for bipolar disorder.

    PubMed

    Bearden, Carrie E; van Erp, Theo G M; Dutton, Rebecca A; Boyle, Christina; Madsen, Sarah; Luders, Eileen; Kieseppa, Tuula; Tuulio-Henriksson, Annamari; Huttunen, Matti; Partonen, Timo; Kaprio, Jaakko; Lönnqvist, Jouko; Thompson, Paul M; Cannon, Tyrone D

    2011-10-01

    Callosal volume reduction has been observed in patients with bipolar disorder, but whether these deficits reflect genetic vulnerability to the illness remains unresolved. Here, we used computational methods to map corpus callosum abnormalities in a population-based sample of twin pairs discordant for bipolar disorder. Twenty-one probands with bipolar I disorder (mean age 44.4 ± 7.5 years; 48% female), 19 of their non-bipolar co-twins, and 34 demographically matched control twin individuals underwent magnetic resonance imaging. Three-dimensional callosal surface models were created to visualize its morphologic variability and to localize group differences. Neurocognitive correlates of callosal area differences were additionally investigated in a subsample of study participants. Bipolar (BPI) probands, but not their co-twins, showed significant callosal thinning and area reduction, most pronounced in the genu and splenium, relative to healthy twins. Altered callosal curvature was additionally observed in BPI probands. In bipolar probands and co-twins, genu and splenium midsagittal areas were significantly correlated with verbal processing speed and response inhibition. These findings suggest that aberrant connections between cortical regions--possibly reflecting decreased myelination of white matter tracts--may be involved in bipolar pathophysiology. However, findings of callosal thinning appear to be disease related, rather than reflecting genetic vulnerability to bipolar illness. PMID:21383237

  1. Automated segmentation of the canine corpus callosum for the measurement of diffusion tensor imaging.

    PubMed

    Peterson, David E; Chen, Steven D; Calabrese, Evan; White, Leonard E; Provenzale, James M

    2016-02-01

    The goal of this study was to apply image registration-based automated segmentation methods to measure diffusion tensor imaging (DTI) metrics within the canine brain. Specifically, we hypothesized that this method could measure DTI metrics within the canine brain with greater reproducibility than with hand-drawn region of interest (ROI) methods. We performed high-resolution post-mortem DTI imaging on two canine brains on a 7 T MR scanner. We designated the two brains as brain 1 and brain 2. We measured DTI metrics within the corpus callosum of brain 1 using a hand-drawn ROI method and an automated segmentation method in which ROIs from brain 2 were transformed into the space of brain 1. We repeated both methods in order to measure their reliability. Mean differences between the two sets of hand-drawn ROIs ranged from 4% to 10%. Mean differences between the hand-drawn ROIs and the automated ROIs were less than 3%. The mean differences between the first and second automated ROIs were all less than 0.25%. Our findings indicate that the image registration-based automated segmentation method was clearly the more reproducible method. These results provide the groundwork for using image registration-based automated segmentation methods to measure DTI metrics within the canine brain. Such methods will facilitate the study of white matter pathology in canine models of neurologic disease. PMID:26577603

  2. Changes in the corpus callosum in women with late-stage bipolar disorder

    PubMed Central

    Lavagnino, Luca; Cao, Bo; Mwangi, Benson; Wu, Mon-Ju; Sanches, Marsal; Zunta-Soares, Giovana B; Kapczinski, Flavio; Soares, Jair

    2015-01-01

    Objective The present study investigated the differences in corpus callosum (CC) volumes between women with early stage and late stage bipolar I (BP I) disorder using the criteria previously described in the literature. Method We compared women with early and late stage BP I using criteria described in the Staging Systems Task Force Report of the International Society for Bipolar Disorders. We included 20 patients with early stage and 21 patients with late stage BP Iand a group of 25 healthy controls. Patients and controls underwent structural magnetic resonance imaging. Information on the clinical features of bipolar disorder was collected using a standardized questionnaire. Anatomical volumes of 5 regions of CC were compared between the three groups. Results Women with late-stage BP I disorder had reduced posterior CC volumes compared to early stage bipolar I patients and controls (F=6.05; P=0.004). The difference was significant after controlling for age, comorbidity with post-traumatic stress disorder, psychotic symptoms during mood episodes, and current use of medication. Conclusion The posterior CC was significantly decreased in volume in women with late-stage bipolar disorder. These findings suggest that CC may be an anatomical target of neuroprogression in the course of bipolar disorder in women. PMID:25640667

  3. Corpus Callosum Integrity and Neuropsychological Performance after Traumatic Brain Injury: A Diffusion Tensor Imaging Study

    PubMed Central

    Arenth, Patricia M.; Russell, Kathryn C.; Scanlon, Joelle M.; Kessler, Lauren J.; Ricker, Joseph H.

    2016-01-01

    Objective To conduct a detailed analysis of DTI parameters [fractional anisotropy (FA) and radial diffusivity (RD)] to evaluate white matter integrity in the corpus callosum (CC), and to examine correlations between DTI data and performance on multiple measures of cognitive functioning. Method 12 participants with a history of complicated mild, moderate, or severe TBI, and 12 control participants completed both standardized and experimental neuropsychological testing and an FMRI session, including DTI. Measures Detailed DTI analysis examined between-group and within-group comparisons of DTI parameters and demographic information, as well as measures of episodic memory and executive functioning. Results Differences were found between groups such that the TBI group demonstrated DTI values suggesting decreased white matter integrity, and correlations with injury severity. Both groups showed correlations between DTI parameters and cognitive measures, with more significant correlations observed for the TBI group. White matter changes in the CC were evident chronically, and were related to severity of injury. Conclusions DTI parameters suggesting disruptions in white matter may be implicated in impaired performance, both in terms of cognitive tasks and reaction time, after TBI. PMID:23558829

  4. Structural and functional brain rewiring clarifies preserved interhemispheric transfer in humans born without the corpus callosum.

    PubMed

    Tovar-Moll, Fernanda; Monteiro, Myriam; Andrade, Juliana; Bramati, Ivanei E; Vianna-Barbosa, Rodrigo; Marins, Theo; Rodrigues, Erika; Dantas, Natalia; Behrens, Timothy E J; de Oliveira-Souza, Ricardo; Moll, Jorge; Lent, Roberto

    2014-05-27

    Why do humans born without the corpus callosum, the major interhemispheric commissure, lack the disconnection syndrome classically described in callosotomized patients? This paradox was discovered by Nobel laureate Roger Sperry in 1968, and has remained unsolved since then. To tackle the hypothesis that alternative neural pathways could explain this puzzle, we investigated patients with callosal dysgenesis using structural and functional neuroimaging, as well as neuropsychological assessments. We identified two anomalous white-matter tracts by deterministic and probabilistic tractography, and provide supporting resting-state functional neuroimaging and neuropsychological evidence for their functional role in preserved interhemispheric transfer of complex tactile information, such as object recognition. These compensatory pathways connect the homotopic posterior parietal cortical areas (Brodmann areas 39 and surroundings) via the posterior and anterior commissures. We propose that anomalous brain circuitry of callosal dysgenesis is determined by long-distance plasticity, a set of hardware changes occurring in the developing brain after pathological interference. So far unknown, these pathological changes somehow divert growing axons away from the dorsal midline, creating alternative tracts through the ventral forebrain and the dorsal midbrain midline, with partial compensatory effects to the interhemispheric transfer of cortical function. PMID:24821757

  5. Long-Term Abnormalities in the Corpus Callosum of Female Concussed Athletes.

    PubMed

    Chamard, Emilie; Lefebvre, Genevieve; Lassonde, Maryse; Theoret, Hugo

    2016-07-01

    Concussion is an injury affecting millions of individuals annually that can be associated with long-term sequelae. Recent studies have reported long-term abnormalities in the white matter (WM) tracts of male athletes. The corpus callosum (CC) and corticospinal tract (CST) have been shown to be particularly vulnerable to concussion, which may be related to abnormal interhemispheric functional connectivity and motor impairments. These anatomical pathways, however, have not been investigated in female athletes despite the functional significance of the CC and CST to adequate sports performance. In the present study, 8 healthy, unconcussed female athletes (soccer, hockey) were compared with 10 female athletes (soccer, hockey, water polo) 6 months post-concussion. Diffusion tensor imaging (DTI) of the CC and CST was conducted in a 3T magnetic resonance imaging (MRI) scanner. DTI analysis showed no significant differences between groups within the CST but revealed differences between groups in the CC. The concussed group had lower mean diffusivity (t = 2.14; p = 0.048) and lower radial diffusivity (t = 2.91; p = 0.010) in the region of the CC projecting to the prefrontal cortex. A lower volume of WM fibers was found in the region projecting to the premotor and supplementary motor areas (t = 2.14; p = 0.048). Finally, lower axial diffusivity (AD) was observed in the CC area projecting mainly to the parietal and temporal area (t = 2.23; p = 0.041). Long-term alterations in the CC of female athletes appear to affect mostly the anterior part of the CC projecting to the prefrontal and premotor areas. Further studies are needed to determine whether these alterations are associated with a higher risk of sustaining a subsequent concussive injury. PMID:26414496

  6. Effect of registration on corpus callosum population differences found with DBM analysis

    NASA Astrophysics Data System (ADS)

    Han, Zhaoying; Thornton-Wells, Tricia A.; Gore, John C.; Dawant, Benoit M.

    2011-03-01

    Deformation Based Morphometry (DBM) is a relatively new method used for characterizing anatomical differences among populations. DBM is based on the analysis of the deformation fields generated by non-rigid registration algorithms, which warp the individual volumes to one standard coordinate system. Although several studies have compared non-rigid registration algorithms for segmentation tasks, few studies have compared the effect of the registration algorithm on population differences that may be uncovered through DBM. In this study, we compared DBM results obtained with five well established non-rigid registration algorithms on the corpus callosum (CC) in thirteen subjects with Williams Syndrome (WS) and thirteen Normal Control (NC) subjects. The five non-rigid registration algorithms include: (1) The Adaptive Basis Algorithm (ABA); (2) Image Registration Toolkit (IRTK); (3) FSL Nonlinear Image Registration Tool (FSL); (4) Automatic Registration Tools (ART); and (5) the normalization algorithm available in SPM8. For each algorithm, the 3D deformation fields from all subjects to the atlas were obtained and used to calculate the Jacobian determinant (JAC) at each voxel in the mid-sagittal slice of the CC. The mean JAC maps for each group were compared quantitatively across different nonrigid registration algorithms. An ANOVA test performed on the means of the JAC over the Genu and the Splenium ROIs shows the JAC differences between nonrigid registration algorithms are statistically significant over the Genu for both groups and over the Splenium for the NC group. These results suggest that it is important to consider the effect of registration when using DBM to compute morphological differences in populations.

  7. Arteriovenous malformations of the corpus callosum: Pooled analysis and systematic review of literature

    PubMed Central

    Pabaney, Aqueel H.; Ali, Rushna; Kole, Maximillian; Malik, Ghaus M.

    2016-01-01

    Background: Arteriovenous malformations (AVMs) of the corpus callosum (CC) are rare entities. We performed a systematic review of the available literature to better define the natural history, patient characteristics, and treatment options for these lesions. Methods: A MEDLINE, Google Scholar, and The Cochrane Library search were performed for studies published through June 2015. Data from all eligible studies were used to examine epidemiology, natural history, clinical features, treatment strategies, and outcomes of patients with CC-AVMs. A systematic review and pooled analysis of the literature were performed. Results: Our search yielded 37 reports and 230 patients. Mean age at presentation was 26.8 years (±13.12 years). AVMs were most commonly located in the splenium (43%), followed by the body (31%), and then the genu (23%) of the CC. A Spetzler-Martin grade of III was the most common (37%). One hundred eighty-seven (81.3%) patients presented with hemorrhage, 91 (40%) underwent microsurgical excision, and 87 (38%) underwent endovascular embolization. Radiosurgery was performed on 57 (25%) patients. Complete obliteration of the AVM was achieved in 102 (48.1%) patients and approximately twice as often when microsurgery was performed alone or in combination with other treatment modalities (94% vs. 49%; P < 0.001). Mean modified Rankin Scale (mRS) at presentation was 1.54 and mean mRS at last follow-up was 1.31. This difference was not statistically significant (P = 0.35). Conclusion: We present an analysis of the pooled data in the form of a systematic review focusing on management of CC-AVMs. This review aims to provide a valuable tool to aid in decision making when dealing with this particular subtype of AVM. PMID:27127713

  8. Effects of sex chromosome dosage on corpus callosum morphology in supernumerary sex chromosome aneuploidies

    PubMed Central

    2014-01-01

    Background Supernumerary sex chromosome aneuploidies (sSCA) are characterized by the presence of one or more additional sex chromosomes in an individual’s karyotype; they affect around 1 in 400 individuals. Although there is high variability, each sSCA subtype has a characteristic set of cognitive and physical phenotypes. Here, we investigated the differences in the morphometry of the human corpus callosum (CC) between sex-matched controls 46,XY (N =99), 46,XX (N =93), and six unique sSCA karyotypes: 47,XYY (N =29), 47,XXY (N =58), 48,XXYY (N =20), 47,XXX (N =30), 48,XXXY (N =5), and 49,XXXXY (N =6). Methods We investigated CC morphometry using local and global area, local curvature of the CC boundary, and between-landmark distance analysis (BLDA). We hypothesized that CC morphometry would vary differentially along a proposed spectrum of Y:X chromosome ratio with supernumerary Y karyotypes having the largest CC areas and supernumerary X karyotypes having significantly smaller CC areas. To investigate this, we defined an sSCA spectrum based on a descending Y:X karyotype ratio: 47,XYY, 46,XY, 48,XXYY, 47,XXY, 48,XXXY, 49,XXXXY, 46,XX, 47,XXX. We similarly explored the effects of both X and Y chromosome numbers within sex. Results of shape-based metrics were analyzed using permutation tests consisting of 5,000 iterations. Results Several subregional areas, local curvature, and BLDs differed between groups. Moderate associations were found between area and curvature in relation to the spectrum and X and Y chromosome counts. BLD was strongly associated with X chromosome count in both male and female groups. Conclusions Our results suggest that X- and Y-linked genes have differential effects on CC morphometry. To our knowledge, this is the first study to compare CC morphometry across these extremely rare groups. PMID:25780557

  9. Cognition and the corpus callosum: verbal fluency, visuospatial ability, and language lateralization related to midsagittal surface areas of callosal subregions.

    PubMed

    Hines, M; Chiu, L; McAdams, L A; Bentler, P M; Lipcamon, J

    1992-02-01

    Normal volunteers (28 women), 20-45 years old, completed tests of visuospatial ability, verbal fluency, and language lateralization, and the midsagittal surface areas of the splenium, isthmus, midregion, and genu of the corpus callosum were measured from inversion recovery magnetic resonance images. Multivariate statistics were used to analyze patterns of correlations. Verbal fluency correlated positively with the area of the splenium and with the area of a posterior callosal factor defined largely by the splenium. The posterior callosum, particularly the splenium, also correlated negatively with language lateralization. There were no other consistent brain-behavior relationships. These results are relevant to understanding factors involved in the development of cognitive characteristics that show sex differences and to understanding the neural basis of language lateralization and verbal abilities. PMID:1554435

  10. The corpus callosum modulates spindle-burst activity within homotopic regions of somatosensory cortex in newborn rats.

    PubMed

    Marcano-Reik, Amy Jo; Blumberg, Mark S

    2008-10-01

    The corpus callosum, a major interhemispheric fiber tract, mediates communication between homotopic regions within the primary somatosensory cortex (S1). Recently, in 1- to 6-day-old rats, brief bursts of oscillatory activity - called spindle-bursts (SBs) - were described in cortical somatosensory areas following sensory feedback from sleep-related myoclonic twitches or specific peripheral stimulation. To determine whether interhemispheric communication via the corpus callosum modulates the expression of SBs during this early period of development, we investigated the spontaneous expression of SBs in unanesthetized 1- to 6-day-old rats as well as SBs evoked by plantar surface stimulation of the forepaw. We hypothesized that surgically disrupting transcallosal communication (i.e. with callosotomy) or unilateral pharmacological manipulation of S1 activity (e.g. by blocking muscarinic receptors) would alter S1 activity in one or both hemispheres. First, callosotomy doubled the rate of spontaneous, twitch-related SBs in left and right S1s by reducing the interval between successive SBs. Second, unilateral infusion into the left S1 of the muscarinic receptor antagonist, scopolamine, inhibited SBs in response to right forepaw stimulation; importantly, SBs were now disinhibited in the right S1 to right forepaw stimulation, thus 'unmasking' an ipsilateral representation. Subsequent callosotomy reinstated contralateral SB responses in the left S1. Finally, tactile and proprioceptive stimulation produced dissociable neurophysiological S1 responses; specifically, SBs were produced in response to proprioceptive, but not tactile, stimulation. We conclude that the corpus callosum modulates functionally inhibitory interactions between homotopic regions in left and right S1s during the early developmental period when organized neurophysiological activity is first detected in the neocortex. PMID:18973571

  11. Rare association of thin corpus callosum with infantile tremor syndrome in a 5.5-month-old infant

    PubMed Central

    Sharma, Chandra Madhur; Sharma, Deepti; Kumar, Romal; Ranjan, Rahul

    2015-01-01

    Infantile tremor syndrome (ITS) is a clinical disorder characterized by coarse tremors, anemia and regression of motor and mental milestones, presenting in malnourished children aged between 5 months and 3 years. Few reports of neuroimaging abnormalities in children with ITS are present. The most common finding of neuroimaging in ITS is cerebral atrophy with ex-vacuo enlargement of ventricles and subarachnoid space, some recent reports also showed pontine myelinolysis and cerebral hyperintensities. We did not find any report of thin corpus callosum associated with ITS in the literature. PMID:26557175

  12. Influence of Corpus Callosum Damage on Cognition and Physical Disability in Multiple Sclerosis: A Multimodal Study

    PubMed Central

    Llufriu, Sara; Blanco, Yolanda; Martinez-Heras, Eloy; Casanova-Molla, Jordi; Gabilondo, Iñigo; Sepulveda, Maria; Falcon, Carles; Berenguer, Joan; Bargallo, Nuria; Villoslada, Pablo; Graus, Francesc; Valls-Sole, Josep; Saiz, Albert

    2012-01-01

    Background Corpus callosum (CC) is a common target for multiple sclerosis (MS) pathology. We investigated the influence of CC damage on physical disability and cognitive dysfunction using a multimodal approach. Methods Twenty-one relapsing-remitting MS patients and 13 healthy controls underwent structural MRI and diffusion tensor of the CC (fractional anisotropy; mean diffusivity, MD; radial diffusivity, RD; axial diffusivity). Interhemisferic transfer of motor inhibition was assessed by recording the ipsilateral silent period (iSP) to transcranial magnetic stimulation. We evaluated cognitive function using the Brief Repeatable Battery and physical disability using the Expanded Disability Status Scale (EDSS) and the MS Functional Composite (MSFC) z-score. Results The iSP latency correlated with physical disability scores (r ranged from 0.596 to 0.657, P values from 0.004 to 0.001), and with results of visual memory (r = −0.645, P = 0.002), processing speed (r = −0.51, P = 0.018) and executive cognitive domain tests (r = −0.452, P = 0.039). The area of the rostrum correlated with the EDSS (r = −0.442, P = 0.045). MD and RD correlated with cognitive performance, mainly with results of visual and verbal memory tests (r ranged from −0.446 to −0.546, P values from 0.048 to 0.011). The iSP latency correlated with CC area (r = −0.345, P = 0.049), volume (r = −0.401, P = 0.002), MD (r = 0.404, P = 0.002) and RD (r = 0.415, P = 0.016). Conclusions We found evidence for structural and microstructural CC abnormalities associated with impairment of motor callosal inhibitory conduction in MS. CC damage may contribute to cognitive dysfunction and in less extent to physical disability likely through a disconnection mechanism. PMID:22606347

  13. Corpus callosum agenesis, spastic quadriparesis and irregular lining of the lateral ventricles on CT-scan. A distinct X-linked mental retardation syndrome?

    PubMed

    Vles, J S; Fryns, J P; Folmer, K; Boon, P; Buttiens, M; Grubben, C; Janevski, B

    1990-01-01

    This report gives a description of 4 male patients, two of whom are sibs, two of whom are uncle and cousin. They appear to have psychomotor retardation, spastic quadriparesis and on CT (partial) agencies of the corpus callosum, and irregular lining of the lateral ventricles, without craniofacial abnormalities or seizures. Although the mode of inheritance of agenesis of the corpus callosum is still difficult to establish, in these 4 male patients an X-linked recessive inheritance is the most likely mode. A review of the literature with concern to the heredity of agenesis of the corpus callosum is presented. The clinical and neurological findings in the present four male patients allow for the delineation of a new X-linked mental retardation syndrome. PMID:2081003

  14. Decision-making in individuals with agenesis of the corpus callosum: expectancy-valence in the Iowa Gambling Task.

    PubMed

    Brown, Warren S; Anderson, Luke B; Symington, Melissa F; Paul, Lynn K

    2012-08-01

    Individuals with agenesis of the corpus callosum (ACC) can have intelligence within the normal range, but nevertheless have deficiencies in decision-making and complex novel problem-solving. The specific nature of these problems is not yet clearly understood. The Iowa Gambling Task was used to test decision-making ability and problem-solving in 40 individuals with complete or partial ACC (full-scale intelligence quotient >80) and 26 control participants. The expectancy-valence (EV) model was applied to the trial-by-trial responses of each participant to elucidate differences in decision processes utilized by each group. The ACC group had a lower overall net gain and fewer advantageous choices than controls, but these differences were not statistically significant. Within the EV model, individuals with ACC exhibited significantly higher attention to losses, less consistency in their choice strategy, and greater frequency of switching between decks. They also showed a tendency to be more influenced by recent trials. This outcome is similar to that seen in individuals with Asperger's disorder. Taken together, these results suggest that individuals with ACC have difficulty in inferring game contingencies and forming a coherent selection strategy, implicating the corpus callosum in these decision processes. PMID:22721927

  15. A T1 and DTI fused 3D corpus callosum analysis in pre- vs. post-season contact sports players

    NASA Astrophysics Data System (ADS)

    Lao, Yi; Law, Meng; Shi, Jie; Gajawelli, Niharika; Haas, Lauren; Wang, Yalin; Leporé, Natasha

    2015-01-01

    Sports related traumatic brain injury (TBI) is a worldwide public health issue, and damage to the corpus callosum (CC) has been considered as an important indicator of TBI. However, contact sports players suffer repeated hits to the head during the course of a season even in the absence of diagnosed concussion, and less is known about their effect on callosal anatomy. In addition, T1-weighted and diffusion tensor brain magnetic resonance images (DTI) have been analyzed separately, but a joint analysis of both types of data may increase statistical power and give a more complete understanding of anatomical correlates of subclinical concussions in these athletes. Here, for the first time, we fuse T1 surface-based morphometry and a new DTI analysis on 3D surface representations of the CCs into a single statistical analysis on these subjects. Our new combined method successfully increases detection power in detecting differences between pre- vs. post-season contact sports players. Alterations are found in the ventral genu, isthmus, and splenium of CC. Our findings may inform future health assessments in contact sports players. The new method here is also the first truly multimodal diffusion and T1-weighted analysis of the CC, and may be useful to detect anatomical changes in the corpus callosum in other multimodal datasets.

  16. Abnormal increase of neuronal precursor cells and exacerbated neuroinflammation in the corpus callosum in murine model of systemic lupus erythematosus

    PubMed Central

    Leung, Joseph Wai-Hin; Lau, Benson Wui-Man; Chan, Vera Sau-Fong; Lau, Chak-Sing; So, Kwok-Fai

    2016-01-01

    Purpose: Systemic Lupus Erythematosus (SLE) is an autoimmune disease which is characterised by elevated levels of autoantibodies and cytokines in the body. Via alteration of the regulation of inflammation, damage to different organ systems, including the central nervous system (CNS), was found in SLE patients. Patients diagnosed with SLE were reported to suffer from different kinds of psychiatric signs and symptoms. As neurogenesis has been suggested to be a potential key player of psychiatric symptoms and emotional behavior disturbances, this study aims to investigate whether neurogenesis is altered in an animal model of SLE. Also, neuroinflammation was studied. Methods: Female NZB/W F1 mice were used as an animal model of SLE. Animals were divided into two groups: 1. pre-diseased mice (lupus-prone NZB/W F1 female mice, age 10–15 weeks, negative for proteinuria and with basal levels of serum anti-dsDNA autoantibodies) and 2. diseased mice (NZB/W F1 female mice, > 25 weeks of age, with elevated serum levels of anti-dsDNA autoantibodies and with persistent proteinuria of > 3 mg/ml for more than 2 weeks). Comparisons of the levels of neurogenesis and neuroinflammtion between two groups of mice were studied by the immunohistochemistry. Results: After the onset of SLE symptoms, a reduction of neurogenesis in the hippocampus was found, while there was a dramatic increase of doublecortin (DCX+) neuronal precursor cells in the corpus callosum (CC) and in the subventricular zone (SVZ). Meanwhile, exacerbated inflammation was present in the corpus callosum of the diseased mice, which was suggested by the increased number of GFAP+ cells and IBA-1+ cells. Conclusions: To the best of our knowledge, this is the first study showing an increase of neuronal precursor cells in the corpus callosum of the female NZB/W F1 mice. The present study suggests a coincidence but not a causal relationship between neurogenesis and neuroinflammation. The present results have

  17. Abnormal Corpus Callosum Connectivity, Socio-Communicative Deficits, and Motor Deficits in Children with Autism Spectrum Disorder: A Diffusion Tensor Imaging Study

    ERIC Educational Resources Information Center

    Hanaie, Ryuzo; Mohri, Ikuko; Kagitani-Shimono, Kuriko; Tachibana, Masaya; Matsuzaki, Junko; Watanabe, Yoshiyuki; Fujita, Norihiko; Taniike, Masako

    2014-01-01

    In addition to social and communicative deficits, many studies have reported motor deficits in autism spectrum disorder (ASD). This study investigated the macro and microstructural properties of the corpus callosum (CC) of 18 children with ASD and 12 typically developing controls using diffusion tensor imaging tractography. We aimed to explore…

  18. Functional analysis of genes implicated in Down syndrome: 2. Laterality and corpus callosum size in mice transpolygenic for Down syndrome chromosomal region -1 (DCR-1).

    PubMed

    Roubertoux, Pierre L; Bichler, Zoë; Pinoteau, Walter; Seregaza, Zohra; Fortes, Sylvia; Jamon, Marc; Smith, Desmond J; Rubin, Edward; Migliore-Samour, Danièle; Carlier, Michèle

    2005-05-01

    The association between atypical laterality and mental retardation has been reported several times, particularly in Down syndrome (DS). We investigated common genetic correlates of these components of the syndrome, examining direction (number of right paw entries in the Collins test) and degree (absolute difference between the number of right paw entries and the number of left paw entries) in mice that had incorporated extra-contiguous HSA21 fragments covering DCR-1 (Down Chromosomal Region-1). As corpus callosum size is substantially reduced in DS, and as the structure has been suspected of playing a role in atypical laterality, we also measured the corpus callosum in these mice. Extra copies of two regions (F7 and E6) have been associated with an atypical degree of laterality (strongly reduced degree). Extra copies of E8, G6 and E6 are also linked to the reduced size of the corpus callosum, indicating that the abnormal number of fibers linking the two hemispheres is not associated with atypical laterality in DS. Together, these results indicate that some of the genes involved in atypical laterality and in the reduced size of the corpus callosum in DS are present on DCR-1. An extra copy of F7 and, to a lesser extent, an extra copy of E6, are also associated with cognitive impairment. These results support the hypothesis of common genetic correlates in atypical laterality and mental retardation in DS. PMID:15864448

  19. Mapping average axon diameters in porcine spinal cord white matter and rat corpus callosum using d-PFG MRI

    PubMed Central

    Komlosh, M.E.; Özarslan, E.; Lizak, M. J.; Horkayne-Szakaly, I.; Freidlin, R. Z.; Horkay, F.; Basser, P. J.

    2013-01-01

    Knowledge of microstructural features of nerve fascicles, such as axon diameter, is crucial for understanding normal function in the central and peripheral nervous systems as well as assessing changes due to pathologies. In this study double-pulsed field gradient (d-PFG) filtered MRI was used to map the average axon diameter (AAD) in porcine spinal cord, which was then compared to AADs measured with optical microscopy of the same specimen, as a way to further validate this MRI method. A novel 3D acquisition scheme was then used to obtain AADs in each voxel of a coronal slice of rat brain corpus callosum. AAD measurements were also acquired using optical microscopy performed on histological sections and validated using a novel MRI glass capillary array phantom. PMID:23583426

  20. Hyperlexia and ambient echolalia in a case of cerebral infarction of the left anterior cingulate cortex and corpus callosum.

    PubMed

    Suzuki, Tadashi; Itoh, Shouichi; Hayashi, Mototaka; Kouno, Masako; Takeda, Katsuhiko

    2009-10-01

    We report the case of a 69-year-old woman with cerebral infarction in the left anterior cingulate cortex and corpus callosum. She showed hyperlexia, which was a distinctive reading phenomenon, as well as ambient echolalia. Clinical features also included complex disorders such as visual groping, compulsive manipulation of tools, and callosal disconnection syndrome. She read words written on the cover of a book and repeated words emanating from unrelated conversations around her or from hospital announcements. The combination of these two features due to a focal lesion has never been reported previously. The supplementary motor area may control the execution of established subroutines according to external and internal inputs. Hyperlexia as well as the compulsive manipulation of tools could be interpreted as faulty inhibition of preexisting essentially intact motor subroutines by damage to the anterior cingulate cortex reciprocally interconnected with the supplementary motor area. PMID:19585352

  1. Netrin-DCC signaling regulates corpus callosum formation through attraction of pioneering axons and by modulating Slit2-mediated repulsion.

    PubMed

    Fothergill, Thomas; Donahoo, Amber-Lee S; Douglass, Amelia; Zalucki, Oressia; Yuan, Jiajia; Shu, Tianzhi; Goodhill, Geoffrey J; Richards, Linda J

    2014-05-01

    The left and right sides of the nervous system communicate via commissural axons that cross the midline during development using evolutionarily conserved molecules. These guidance cues have been particularly well studied in the mammalian spinal cord, but it remains unclear whether these guidance mechanisms for commissural axons are similar in the developing forebrain, in particular for the corpus callosum, the largest and most important commissure for cortical function. Here, we show that Netrin1 initially attracts callosal pioneering axons derived from the cingulate cortex, but surprisingly is not attractive for the neocortical callosal axons that make up the bulk of the projection. Instead, we show that Netrin-deleted in colorectal cancer signaling acts in a fundamentally different manner, to prevent the Slit2-mediated repulsion of precrossing axons thereby allowing them to approach and cross the midline. These results provide the first evidence for how callosal axons integrate multiple guidance cues to navigate the midline. PMID:23302812

  2. Exome sequencing identifies recessive CDK5RAP2 variants in patients with isolated agenesis of corpus callosum.

    PubMed

    Jouan, Loubna; Ouled Amar Bencheikh, Bouchra; Daoud, Hussein; Dionne-Laporte, Alexandre; Dobrzeniecka, Sylvia; Spiegelman, Dan; Rochefort, Daniel; Hince, Pascale; Szuto, Anna; Lassonde, Maryse; Barbelanne, Marine; Tsang, William Y; Dion, Patrick A; Théoret, Hugo; Rouleau, Guy A

    2016-04-01

    Agenesis of the corpus callosum (ACC) is a common brain malformation which can be observed either as an isolated condition or as part of numerous congenital syndromes. Therefore, cognitive and neurological involvements in patients with ACC are variable, from mild linguistic and behavioral impairments to more severe neurological deficits. To date, the underlying genetic causes of isolated ACC remains elusive and causative genes have yet to be identified. We performed exome sequencing on three acallosal siblings from the same non-consanguineous family and identified compound heterozygous variants, p.[Gly94Arg];[Asn1232Ser], in the protein encoded by the CDK5RAP2 gene, also known as MCPH3, a gene previously reported to cause autosomal recessive primary microcephaly. Our findings suggest a novel role for this gene in the pathogenesis of isolated ACC. PMID:26197979

  3. Blindness, dancing extremities, and corpus callosum and brain stem involvement: an unusual presentation of fulminant subacute sclerosing panencephalitis.

    PubMed

    Singhi, Pratibha; Saini, Arushi Gahlot; Sankhyan, Naveen; Gupta, Pankaj; Vyas, Sameer

    2015-01-01

    A 4-year-old girl presented with acute visual loss followed 2 weeks later with loss of speech and audition, fulminant neuroregression, and choreo-athetoid movements of extremities. Fundus showed bilateral chorioretinitis. Electroencephalography showed periodic complexes. Measles antibody titers were elevated in both serum and cerebrospinal fluid, consistent with subacute sclerosing panencephalitis. Neuroimaging showed discontiguous involvement of splenium of the corpus callosum and ventral pons with sparing of cortical white matter. Our case highlights the atypical clinical and radiologic presentations of subacute sclerosing panencephalitis. Pediatricians need to be aware that necrotizing chorioretinitis in a child and/or atypical brain stem changes could be the heralding feature of this condition in endemic countries. PMID:24700664

  4. Conduct disorder in females is associated with reduced corpus callosum structural integrity independent of comorbid disorders and exposure to maltreatment.

    PubMed

    Lindner, P; Savic, I; Sitnikov, R; Budhiraja, M; Liu, Y; Jokinen, J; Tiihonen, J; Hodgins, S

    2016-01-01

    The behavioral phenotype and genotype of conduct disorder (CD) differ in males and females. Abnormalities of white matter integrity have been reported among males with CD and antisocial personality disorder (ASPD). Little is known about white matter integrity in females with CD. The present study aimed to determine whether abnormalities of white matter are present among young women who presented CD before the age of 15, and whether abnormalities are independent of the multiple comorbid disorders and experiences of maltreatment characterizing females with CD that may each in themselves be associated with alterations of the white matter. Three groups of women, aged on average 24 years, were scanned using diffusion tensor imaging and compared: 28 with prior CD, three of whom presented ASPD; a clinical comparison (CC) group of 15 women with no history of CD but with similar proportions who presented alcohol dependence, drug dependence, anxiety disorders, depression disorders and physical and sexual abuse as the CD group; and 24 healthy women. Whole-brain, tract-based spatial statistics were computed to investigate differences in fractional anisotropy, axial diffusivity and radial diffusivity. Compared with healthy women, women with prior CD showed widespread reductions in axial diffusivity primarily in frontotemporal regions. After statistically adjusting for comorbid disorders and maltreatment, group differences in the corpus callosum body and genu (including forceps minor) remained significant. Compared with the CC group, women with CD showed reduced fractional anisotropy in the body and genu of the corpus callosum. No differences were detected between the CD and healthy women in the uncinate fasciculus. PMID:26784968

  5. Alcohol exposure during the first two trimesters-equivalent alters the development of corpus callosum projection neurons in the rat.

    PubMed

    Livy, Daniel J; Elberger, Andrea J

    2008-06-01

    Children exposed prenatally to alcohol can display a variety of neural deficits, including an altered development of the corpus callosum (CC), the largest interhemispheric axon pathway in the brain. Furthermore, these children show functional abnormalities that are related to brain regions with significant numbers of CC connections. Little is known about how alcohol imparts influence on CC development, but one possible mechanism is by affecting the corpus callosum projection neurons (CCpn) directly. The purpose of this study was to quantify the effects of prenatal alcohol exposure on the number, size, and distribution of CCpn within the visual cortex. The visual cortex was selected specifically due to the many vision-related deficits noted in fetal alcohol exposed children and because the critical role of the CC in visual cortex development is well documented. Sprague-Dawley rat pups received one of four alcohol dosages during gestational days (G) 1-20, or reared as nutritional or untreated control animals. Each litter was categorized according to the peak blood alcohol concentration experienced. Pups were removed from each litter on days equivalent to G29, G36, G43, and G50, for histology and measurement. Callosal axons were labeled retrogradely to their CCpn using 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) and the CCpn were then examined using confocal laser scanning microscopy. Differences between alcohol-exposed and control animals were observed in CCpn cell body size, number, and location with the cortex. This was particularly true of animals exposed to high doses of alcohol. In addition, some trends of CCpn development were found to be unchanged as a result of prenatal alcohol exposure. The results demonstrate clear differences in the development of CCpn in the visual cortex between alcohol-exposed and control animals and suggest that this development is particularly affected in those animals exposed to high doses of alcohol

  6. Propagation of Epileptiform Events across the Corpus Callosum in a Cingulate Cortical Slice Preparation

    PubMed Central

    Quach-Wong, Bonnie; Sonnenfeld, Julian; Aaron, Gloster

    2012-01-01

    We report on a novel mouse in vitro brain slice preparation that contains intact callosal axons connecting anterior cingulate cortices (ACC). Callosal connections are demonstrated by the ability to regularly record epileptiform events between hemispheres (bilateral events). That the correlation of these events depends on the callosum is demonstrated by the bisection of the callosum in vitro. Epileptiform events are evoked with four different methods: (1) bath application of bicuculline (a GABA-A antagonist); (2) bicuculline+MK801 (an NMDA receptor antagonist), (3) a zero magnesium extracellular solution (0Mg); (4) focal application of bicuculline to a single cortical hemisphere. Significant increases in the number of epileptiform events, as well as increases in the ratio of bilateral events to unilateral events, are observed during bath applications of bicuculline, but not during applications of bicuculline+MK-801. Long ictal-like events (defined as events >20 seconds) are only observed in 0Mg. Whole cell patch clamp recordings of single neurons reveal strong feedforward inhibition during focal epileptiform events in the contralateral hemisphere. Within the ACC, we find differences between the rostral areas of ACC vs. caudal ACC in terms of connectivity between hemispheres, with the caudal regions demonstrating shorter interhemispheric latencies. The morphologies of many patch clamped neurons show callosally-spanning axons, again demonstrating intact callosal circuits in this in vitro preparation. PMID:22363643

  7. A 54 Mb 11qter duplication and 0.9 Mb 1q44 deletion in a child with laryngomalacia and agenesis of corpus callosum

    PubMed Central

    2011-01-01

    Background Partial Trisomy 11q syndrome (or Duplication 11q) has defined clinical features and is documented as a rare syndrome by National Organization of Rare Disorders (NORD). Deletion 1q44 (or Monosomy 1q44) is a well-defined syndrome, but there is controversy about the genes lying in 1q44 region, responsible for agenesis of the corpus callosum. We report a female child with the rare Partial Trisomy 11q syndrome and Deletion 1q44 syndrome. The genomic imbalance in the proband was used for molecular characterization of the critical genes in 1q44 region for agenesis of corpus callosum. Some genes in 11q14q25 may be responsible for laryngomalacia. Results We report a female child with dysmorphic features, microcephaly, growth retardation, seizures, acyanotic heart disease, and hand and foot deformities. She had agenesis of corpus callosum, laryngomalacia, anterior ectopic anus, esophageal reflux and respiratory distress. Chromosome analysis revealed a derivative chromosome 1. Her karyotype was 46,XX,der(1)t(1;11)(q44;q14)pat. The mother had a normal karyotype and the karyotype of the father was 46,XY,t(1;11)(q44;q14). SNP array analysis showed that the proband had a 54 Mb duplication of 11q14q25 and a 0.9 Mb deletion of the submicroscopic subtelomeric 1q44 region. Fluorescence Insitu Hybridisation confirmed the duplication of 11qter and deletion of 1qter. Conclusion Laryngomalacia or obstruction of the upper airway is the outcome of increased dosage of some genes due to Partial Trisomy 11q Syndrome. In association with other phenotypic features, agenesis of corpus callosum appears to be a landmark phenotype for Deletion 1q44 syndrome, the critical genes lying proximal to SMYD3 in 1q44 region. PMID:21936942

  8. [Neuropsychological studies of two subjects after the transection of the splenium of the corpus callosum (Part 3. The tactile recognition) (author's transl)].

    PubMed

    Watanabe, S; Hojo, K; Sato, T; Yoshimura, I; Tanaka, T

    1979-11-01

    We made the neuropsychological tactile studies of two right-handed subjects who had undergone the transection of the splenium of the corpus callosum for the pineal operation (the teratoma by the histopathological examination). The transaction grade was 2.0 cm and 2.5 cm. In this paper we examined the tactile recognition neuropsychologically: A. Superficial sensory modalities: light touch, pain perception, temperature discriminations. B. Deep sensory modalities: vibration perception, position sense, motor sense. C. Perception of material: rough or smooth, heavy or light, hard or soft. D. Perception of size: appreciation of shape in two dimentions: circle, triangle, square, cross, rhomb, appreciation of form in three dimensions: ball, column, cone, trignonal prism, cube. E. Identification of simple objects: eraser, pencil, hair pencil, fountainpen, telephone, glasses. F. Identification of japanese letters: Kana (phonetic symbols) and Kanji (essentially nonphonetic logographic symbols representing lexical morphemes). According to the papers of Akelaitis, Van Vleuten, Goldstein, the subjects after the transection of the corpus callosum could name the objects and the card board letters placed in their right hands with their eyes closed, but they could not name in their left hand by contrast. In our subjects, the identification of simple objects and the identification of japanese letters were complete good. But they had the neuropsychological visual and auditive disorders. The result shows that the commissure fibres of the identification of the simple objects and letters of two hemispheres does not connect through the splenium of the corpus callosum. PMID:526359

  9. Corpus Callosum Structure is Topographically Correlated with the Early Course of Cognition and Depression in Alzheimer's Disease.

    PubMed

    Di Paola, Margherita; Phillips, Owen; Orfei, Maria Donata; Piras, Fabrizio; Cacciari, Claudia; Caltagirone, Carlo; Spalletta, Gianfranco

    2015-01-01

    Corpus callosum (CC) abnormalities may cause cognitive and neuropsychiatric complications due to reduced hemispheric integration. Over a one-year period, we investigated whether the CC structure of 20 patients with mild Alzheimer's disease (AD) was linked to the evolution of cognitive and neuropsychiatric symptoms. We also investigated whether this anatomical-clinical relationship was localized topographically on the CC by combining voxel-based morphometry and diffusion tensor imaging approaches. We assessed patients' global cognitive deterioration and neuropsychiatric symptoms with the Mini-Mental State Examination and the Neuropsychiatric Inventory. Increased global cognitive deterioration during the early course of AD was significantly related to reduced white matter density (p = 0.004) and fractional anisotropy (FA) (p = 0.012) and increased mean diffusivity (MD) (p = 0.017) at the level of the CC isthmus/splenium. Further, increased depression severity was significantly related to reduced FA (p = 0.008) and increased MD (p = 0.018) at the level of the CC rostrum. These results indicate that changes in early myelinated CC fibers, which subserve the lateral temporal and parietal cortices and are less vulnerable to damage, may be related to cognitive impairment. Furthermore, changes in late myelinated CC fibers, which connect the orbitofrontal cortices and are more vulnerable to damage, may be related to the earliest neuropsychiatric symptoms of AD, such as depression. PMID:25649657

  10. Inter-hemispheric functional dysconnectivity mediates the association of corpus callosum degeneration with memory impairment in AD and amnestic MCI.

    PubMed

    Qiu, Yingwei; Liu, Siwei; Hilal, Saima; Loke, Yng Miin; Ikram, Mohammad Kamran; Xu, Xin; Yeow Tan, Boon; Venketasubramanian, Narayanaswamy; Chen, Christopher Li-Hsian; Zhou, Juan

    2016-01-01

    Evidences suggested that both corpus callosum (CC) degeneration and alternations of homotopic inter-hemispheric functional connectivity (FC) are present in Alzheimer's disease (AD). However, the associations between region-specific CC degeneration and homotopic inter-hemispheric FC and their relationships with memory deficits in AD remain uncharacterized. We hypothesized that selective CC degeneration is associated with memory impairment in AD and amnestic mild cognitive impairment (aMCI), which is mediated by homotopic inter-hemispheric functional dysconnectivity. Using structural magnetic resonance imaging (MRI) and task-free functional MRI, we assessed the CC volume and inter-hemispheric FC in 66 healthy controls, 41 aMCI and 41 AD. As expected, AD had CC degeneration and attenuated inter-hemispheric homotopic FC. Nevertheless, aMCI had relatively less severe CC degeneration (mainly in mid-anterior, central, and mid-posterior) and no reduction in inter-hemispheric homotopic FC. The degeneration of each CC sub-region was associated with specific inter-hemispheric homotopic functional disconnections in AD and aMCI. More importantly, impairment of inter-hemispheric homotopic FC partially mediated the association between CC (particularly the central and posterior parts) degeneration and memory deficit. Notably, these results remained after controlling for hippocampal volume. Our findings shed light on how CC degeneration and the related inter-hemispheric FC impact memory impairment in early stage of AD. PMID:27581062

  11. Inter-hemispheric functional dysconnectivity mediates the association of corpus callosum degeneration with memory impairment in AD and amnestic MCI

    PubMed Central

    Qiu, Yingwei; Liu, Siwei; Hilal, Saima; Loke, Yng Miin; Ikram, Mohammad Kamran; Xu, Xin; Yeow Tan, Boon; Venketasubramanian, Narayanaswamy; Chen, Christopher Li-Hsian; Zhou, Juan

    2016-01-01

    Evidences suggested that both corpus callosum (CC) degeneration and alternations of homotopic inter-hemispheric functional connectivity (FC) are present in Alzheimer’s disease (AD). However, the associations between region-specific CC degeneration and homotopic inter-hemispheric FC and their relationships with memory deficits in AD remain uncharacterized. We hypothesized that selective CC degeneration is associated with memory impairment in AD and amnestic mild cognitive impairment (aMCI), which is mediated by homotopic inter-hemispheric functional dysconnectivity. Using structural magnetic resonance imaging (MRI) and task-free functional MRI, we assessed the CC volume and inter-hemispheric FC in 66 healthy controls, 41 aMCI and 41 AD. As expected, AD had CC degeneration and attenuated inter-hemispheric homotopic FC. Nevertheless, aMCI had relatively less severe CC degeneration (mainly in mid-anterior, central, and mid-posterior) and no reduction in inter-hemispheric homotopic FC. The degeneration of each CC sub-region was associated with specific inter-hemispheric homotopic functional disconnections in AD and aMCI. More importantly, impairment of inter-hemispheric homotopic FC partially mediated the association between CC (particularly the central and posterior parts) degeneration and memory deficit. Notably, these results remained after controlling for hippocampal volume. Our findings shed light on how CC degeneration and the related inter-hemispheric FC impact memory impairment in early stage of AD. PMID:27581062

  12. Age at First Exposure to Football Is Associated with Altered Corpus Callosum White Matter Microstructure in Former Professional Football Players.

    PubMed

    Stamm, Julie M; Koerte, Inga K; Muehlmann, Marc; Pasternak, Ofer; Bourlas, Alexandra P; Baugh, Christine M; Giwerc, Michelle Y; Zhu, Anni; Coleman, Michael J; Bouix, Sylvain; Fritts, Nathan G; Martin, Brett M; Chaisson, Christine; McClean, Michael D; Lin, Alexander P; Cantu, Robert C; Tripodis, Yorghos; Stern, Robert A; Shenton, Martha E

    2015-11-15

    Youth football players may incur hundreds of repetitive head impacts (RHI) in one season. Our recent research suggests that exposure to RHI during a critical neurodevelopmental period prior to age 12 may lead to greater later-life mood, behavioral, and cognitive impairments. Here, we examine the relationship between age of first exposure (AFE) to RHI through tackle football and later-life corpus callosum (CC) microstructure using magnetic resonance diffusion tensor imaging (DTI). Forty retired National Football League (NFL) players, ages 40-65, were matched by age and divided into two groups based on their AFE to tackle football: before age 12 or at age 12 or older. Participants underwent DTI on a 3 Tesla Siemens (TIM-Verio) magnet. The whole CC and five subregions were defined and seeded using deterministic tractography. Dependent measures were fractional anisotropy (FA), trace, axial diffusivity, and radial diffusivity. Results showed that former NFL players in the AFE <12 group had significantly lower FA in anterior three CC regions and higher radial diffusivity in the most anterior CC region than those in the AFE ≥12 group. This is the first study to find a relationship between AFE to RHI and later-life CC microstructure. These results suggest that incurring RHI during critical periods of CC development may disrupt neurodevelopmental processes, including myelination, resulting in altered CC microstructure. PMID:26200068

  13. A DTI study on the corpus callosum of treatment-naïve boys with 'pure' Tourette syndrome.

    PubMed

    Wolff, Nicole; Luehr, Ina; Sender, Jennifer; Ehrlich, Stefan; Schmidt-Samoa, Carsten; Dechent, Peter; Roessner, Veit

    2016-01-30

    Disturbances in the corpus callosum (CC) indicating altered interhemispheric connectivity have been associated with Tourette syndrome (TS). The objective of the present study was to refine knowledge about interhemispheric connectivity in TS by analyzing four different diffusion tensor imaging (DTI) parameters in a very homogeneous group of treatment-naïve boys with pure TS in comparison to male healthy controls (HC). Fractional anisotropy (FA), radial diffusivity (RD), axial diffusivity (AD) and mean diffusivity (MD) of five CC-segments were assessed from DTI of 26 treatment-naïve boys with pure TS and 24 HC. We observed no group differences in both FA and RD. However, we found a significant effect for AD and a trend for MD, being both reduced in boys with TS in comparison to HC. Moreover, a negative correlation between AD and the Yale Global Tic Severity Scale total score was observed. Reduced AD of the CC in treatment-naïve boys with pure TS in comparison to HC may indicate that significant alterations in white matter microstructure of the CC contribute to tic symptomatology per se and seem not to be related to confounders such as consequences of long-term medication, tic performance or tic suppression. PMID:26747579

  14. The desmosterolosis phenotype: spasticity, microcephaly and micrognathia with agenesis of corpus callosum and loss of white matter

    PubMed Central

    Zolotushko, Jenny; Flusser, Hagit; Markus, Barak; Shelef, Ilan; Langer, Yshaia; Heverin, Maura; Björkhem, Ingemar; Sivan, Sara; Birk, Ohad S

    2011-01-01

    Desmosterolosis is a rare autosomal recessive disorder of elevated levels of the cholesterol precursor desmosterol in plasma, tissue and cultured cells. With only two sporadic cases described to date with two very different phenotypes, the clinical entity arising from mutations in 24-dehydrocholesterol reductase (DHCR24) has yet to be defined. We now describe consanguineous Bedouin kindred with four surviving affected individuals, all presenting with severe failure to thrive, psychomotor retardation, microcephaly, micrognathia and spasticity with variable degree of hand contractures. Convulsions near birth, nystagmus and strabismus were found in most. Brain MRI demonstrated significant reduction in white matter and near agenesis of corpus callosum in all. Genome-wide linkage analysis and fine mapping defined a 6.75 cM disease-associated locus in chromosome 1 (maximum multipoint LOD score of six), and sequencing of candidate genes within this locus identified in the affected individuals a homozygous missense mutation in DHCR24 leading to dramatically augmented plasma desmosterol levels. We thus establish a clear consistent phenotype of desmosterolosis (MIM 602398). PMID:21559050

  15. Performance asymmetries in tool use are associated with corpus callosum integrity in chimpanzees (Pan troglodytes): a diffusion tensor imaging study.

    PubMed

    Phillips, Kimberley A; Schaeffer, Jennifer; Barrett, Elizabeth; Hopkins, William D

    2013-02-01

    The authors examined the relationship of corpus callosum (CC) morphology and organization to hand preference and performance on a motor skill task in chimpanzees. Handedness was assessed using a complex tool use task that simulated termite fishing. Chimpanzees were initially allowed to perform the task wherein they could choose which hand to use (preference measure), then they were required to complete trials using each hand (performance measure). Two measures were used to assess the CC: midsagittal area obtained from in vivo magnetic resonance images and density of transcallosal connections as determined by fractional anisotropy values obtained from diffusion tensor imaging. The authors hypothesized that chimpanzees would perform better on their preferred hand compared to the nonpreferred hand, and that strength of behavioral lateralization (rather the direction) on this task would be negatively correlated to regions of the CC involved in motor processing. Results indicate that the preferred hand was the most adept hand. Performance asymmetries correlated with fractional anisotropy measures but not area measures of the CC. PMID:23398443

  16. Agenesis of the corpus callosum and gray matter heterotopia in three patients with constitutional mismatch repair deficiency syndrome

    PubMed Central

    Baas, Annette F; Gabbett, Michael; Rimac, Milan; Kansikas, Minttu; Raphael, Martine; Nievelstein, Rutger AJ; Nicholls, Wayne; Offerhaus, Johan; Bodmer, Danielle; Wernstedt, Annekatrin; Krabichler, Birgit; Strasser, Ulrich; Nyström, Minna; Zschocke, Johannes; Robertson, Stephen P; van Haelst, Mieke M; Wimmer, Katharina

    2013-01-01

    Constitutional mismatch repair deficiency (CMMR-D) syndrome is a rare inherited childhood cancer predisposition caused by biallelic germline mutations in one of the four mismatch repair (MMR)-genes, MLH1, MSH2, MSH6 or PMS2. Owing to a wide tumor spectrum, the lack of specific clinical features and the overlap with other cancer predisposing syndromes, diagnosis of CMMR-D is often delayed in pediatric cancer patients. Here, we report of three new CMMR-D patients all of whom developed more than one malignancy. The common finding in these three patients is agenesis of the corpus callosum (ACC). Gray matter heterotopia is present in two patients. One of the 57 previously reported CMMR-D patients with brain tumors (therefore all likely had cerebral imaging) also had ACC. With the present report the prevalence of cerebral malformations is at least 4/60 (6.6%). This number is well above the population birth prevalence of 0.09–0.36 live births with these cerebral malformations, suggesting that ACC and heterotopia are features of CMMR-D. Therefore, the presence of cerebral malformations in pediatric cancer patients should alert to the possible diagnosis of CMMR-D. ACC and gray matter heterotopia are the first congenital malformations described to occur at higher frequency in CMMR-D patients than in the general population. Further systematic evaluations of CMMR-D patients are needed to identify possible other malformations associated with this syndrome. PMID:22692065

  17. Application of fractal and grey level co-occurrence matrix analysis in evaluation of brain corpus callosum and cingulum architecture.

    PubMed

    Pantic, Igor; Dacic, Sanja; Brkic, Predrag; Lavrnja, Irena; Pantic, Senka; Jovanovic, Tomislav; Pekovic, Sanja

    2014-10-01

    This aim of this study was to assess the discriminatory value of fractal and grey level co-occurrence matrix (GLCM) analysis methods in standard microscopy analysis of two histologically similar brain white mass regions that have different nerve fiber orientation. A total of 160 digital micrographs of thionine-stained rat brain white mass were acquired using a Pro-MicroScan DEM-200 instrument. Eighty micrographs from the anterior corpus callosum and eighty from the anterior cingulum areas of the brain were analyzed. The micrographs were evaluated using the National Institutes of Health ImageJ software and its plugins. For each micrograph, seven parameters were calculated: angular second moment, inverse difference moment, GLCM contrast, GLCM correlation, GLCM variance, fractal dimension, and lacunarity. Using the Receiver operating characteristic analysis, the highest discriminatory value was determined for inverse difference moment (IDM) (area under the receiver operating characteristic (ROC) curve equaled 0.925, and for the criterion IDM≤0.610 the sensitivity and specificity were 82.5 and 87.5%, respectively). Most of the other parameters also showed good sensitivity and specificity. The results indicate that GLCM and fractal analysis methods, when applied together in brain histology analysis, are highly capable of discriminating white mass structures that have different axonal orientation. PMID:24967845

  18. Plasticity of Interhemispheric Temporal Lobe White Matter Pathways Due to Early Disruption of Corpus Callosum Development in Spina Bifida.

    PubMed

    Bradley, Kailyn A; Juranek, Jenifer; Romanowska-Pawliczek, Anna; Hannay, H Julia; Cirino, Paul T; Dennis, Maureen; Kramer, Larry A; Fletcher, Jack M

    2016-04-01

    Spina bifida myelomeningocele (SBM) is commonly associated with anomalous development of the corpus callosum (CC) because of congenital partial hypogenesis and hydrocephalus-related hypoplasia. It represents a model disorder to examine the effects of early disruption of CC neurodevelopment and the plasticity of interhemispheric white matter connections. Diffusion tensor imaging was acquired on 76 individuals with SBM and 27 typically developing individuals, aged 8-36 years. Probabilistic tractography was used to isolate the interhemispheric connections between the posterior superior temporal lobes, which typically traverse the posterior third of the CC. Early disruption of CC development resulted in restructuring of interhemispheric connections through alternate commissures, particularly the anterior commissure (AC). These rerouted fibers were present in people with SBM and both CC hypoplasia and hypogenesis. In addition, microstructural integrity was reduced in the interhemispheric temporal tract in people with SBM, indexed by lower fractional anisotropy, axial diffusivity, and higher radial diffusivity. Interhemispheric temporal tract volume was positively correlated with total volume of the CC, such that more severe underdevelopment of the CC was associated with fewer connections between the posterior temporal lobes. Therefore, both the macrostructure and microstructure of this interhemispheric tract were reduced, presumably as a result of more extensive CC malformation. The current findings suggest that early disruption in CC development reroutes interhemispheric temporal fibers through both the AC and more anterior sections of the CC in support of persistent hypotheses that the AC may serve a compensatory function in atypical CC development. PMID:26798959

  19. Restricted diffusion in the splenium of the corpus callosum in organophosphate induced delayed neuropathy: case report and review of literatures

    PubMed Central

    Wang, Jie; Shao, Yankun; Shi, Kai; Yang, Hong; Li, Miao

    2015-01-01

    We described a 35 year-old female who developed organophosphate induced delayed neuropathy (OPIDN) with an unusal clinical manifestation and neuroradiological presentation. Case report: A 35-year-old woman came into contact with organophosphate pesticide by remissly inhalation. She got transient unconsciousness lasting for nearly 2 hours and developed transient hematuria and hyperhidrotic subsequently. She received atropine as treatment and got a satisfying recovery and was hospital discharged without any symptoms. But 20 days later the patient displayed symptoms including headache, vertigo, mental and memory decline, and was hospitalized again. Clinical manifestations, laboratorial findings, images data will be presented. The brain magnetic resonance imaging (MRI) showed an unusal neuroradiological presentation characterized by restricted diffusion in the splenium of the corpus callosum. The patient recovered satisfactorily after administration of corticosteroids and immunogloblin. Conclusion: OPIDN may develop in some susceptible individuals even by inhalation and sometimes with central nervous system involvement. Treatment with corticosteroids and intravenous immunogloblins was found to achieve good results. PMID:26550404

  20. Diffusion abnormalities of the corpus callosum in patients receiving bevacizumab for malignant brain tumors: suspected treatment toxicity.

    PubMed

    Futterer, Stephen F; Nemeth, Alexander J; Grimm, Sean A; Ragin, Ann B; Chandler, James P; Muro, Kenji; Marymont, Maryanne H; Raizer, Jeffrey J

    2014-05-01

    Bevacizumab has been reported to cause diffusion restriction in the tumor bed of patients with malignant gliomas. This study evaluated prolonged diffusion restriction, in the corpus callosum (CC), of patients with malignant brain tumors treated with bevacizumab. We retrospectively reviewed our database of patients treated with bevacizumab for malignant brain tumors looking for those with restricted diffusion in the CC. CC ADC ratio measurements were obtained prior to and following treatment. Correlation was made with biopsy (n = 3) and MR perfusion (n = 7) and PET (n = 4). The temporal evolution of these changes relative to therapy was examined with mixed effects regression analysis. Nine patients (eight malignant gliomas, one malignant meningioma) out of 146 patients were found to have developed areas of diffusion restriction in the CC. These areas tended to enlarge and coalesce over serial MRIs and persisted for up to 22 months. Hypoperfusion was demonstrated in MR perfusion in 7/7. PET was hypometabolic in all 4. Biopsy of the CC showed no tumor in 3/3. ADC ratio measurements indicated a significant overall effect of time (F(16,60) = 11.2; p < 0.0001), consistent with persistent diffusion restriction over the measured time periods. Bevacizumab causes prolonged diffusion restriction in the CC. The negative MR perfusion, FDG PET and histopathology suggest this is a toxicity of bevacizumab and not active tumor. Awareness of these changes can assist in patient care. PMID:24574050

  1. Abnormalities of white matter integrity in the corpus callosum of adolescents with PTSD after childhood sexual abuse: a DTI study.

    PubMed

    Rinne-Albers, Mirjam A W; van der Werff, Steven J A; van Hoof, Marie-José; van Lang, Natasja D; Lamers-Winkelman, Francien; Rombouts, Serge A; Vermeiren, Robert R J M; van der Wee, Nic J A

    2016-08-01

    This study seeks to determine whether white matter integrity in the brain differs between adolescents with post-traumatic stress disorder (PTSD) due to childhood sexual abuse (CSA) and matched healthy adolescents and whether there is a relationship between white matter integrity and symptom severity in the patient group. Using 3T diffusion tensor imaging, we examined fractional anisotropy (FA) in a group of adolescents with CSA-related PTSD (n = 20) and matched healthy controls (n = 20), in a region of interest consisting of the bilateral uncinate fasciculus (UF), the genu, splenium and body of the corpus callosum (CC), and the bilateral cingulum. In addition, we performed an exploratory whole brain analysis. Trauma symptomatology was measured with the Trauma Symptom Checklist for Children (TSCC) to enable correlational analyses between FA differences and trauma symptomatology. The PTSD group had significantly lower FA values in the genu, midbody and splenium of the CC in comparison with controls (p < 0.05, tfce corrected). Post hoc analyses of the eigenvalues of the DTI scan showed increased radial and mean diffusivity in the patient group. In addition, we found a significant negative correlation between scores on the anger subscale of the TSCC and FA values in the left body of the CC in patients (p < 0.05). Adolescents with CSA-related PTSD show decreased FA in the CC, with abnormalities in the integrity of the left body of the CC being related to anger symptoms. These findings suggest that early trauma exposure affects the development of the CC, which may play a role in the pathophysiology of PTSD in adolescents. PMID:26700102

  2. Reduced Fractional Anisotropy of Corpus Callosum Modulates Inter-Hemispheric Resting State Functional Connectivity in Migraine Patients without Aura

    PubMed Central

    Yuan, Kai; Qin, Wei; Liu, Peng; Zhao, Ling; Yu, Dahua; Zhao, Limei; Dong, Minghao; Liu, Jixin; Yang, Xuejuan; von Deneen, Karen M.; Liang, Fanrong; Tian, Jie

    2012-01-01

    Background Diffusion tensor imaging (DTI) study revealed reduced fractional anisotropy (FA) values in the corpus callosum (CC) in migraine patients without aura. Abnormalities in white matter integrity, particularly in the CC, may affect inter-hemispheric resting state functional connectivity (RSFC). Unfortunately, relatively little is known about the alterations in functional interactions between the cerebral hemispheres during resting state in migraine patients without aura, and even less about how the inter-hemispheric RSFC are affected by the abnormalities of the CC. Methods and findings Twenty-one migraine patients without aura and 21 healthy controls participated in this study, age-, sex-, and education-matched. Tract-based spatial statistics (TBSS) was employed to investigate the white matter alterations of the CC. Meanwhile, voxel-mirrored homotopic connectivity (VMHC) was used to compare the inter-hemispheric RSFC differences between the patients and controls. TBSS analysis revealed reduced FA values in the genu and the splenium of CC in patient group. VMHC analysis showed decreased inter-hemispheric RSFC of anterior cingulate cortex (ACC) in migraine patients without aura relative to that of the controls. Furthermore, in migraine patients without aura, the reduced FA values of the genu of CC correlated with the decreased inter-hemispheric RSFC of the ACC. Conclusions Our findings demonstrated that the migraine patients without aura showed reduced FA values of the genu of CC and decreased inter-hemispheric RSFC of the ACC. The correlation between the above structural and functional changes suggested that the reduced fractional anisotropy (FA) of CC modulates inter-hemispheric VMHC in migraine patients without aura. Our results demonstrated that the VMHC alterations of ACC can reflect the FA changes of the genu of CC in migraine patients without aura. PMID:23029036

  3. Maximum Principal Strain and Strain Rate Associated with Concussion Diagnosis Correlates with Changes in Corpus Callosum White Matter Indices

    PubMed Central

    MCALLISTER, THOMAS W.; FORD, JAMES C.; JI, SONGBAI; BECKWITH, JONATHAN G.; FLASHMAN, LAURA A.; PAULSEN, KEITH; GREENWALD, RICHARD M.

    2014-01-01

    On-field monitoring of head impacts, combined with finite element (FE) biomechanical simulation, allow for predictions of regional strain associated with a diagnosed concussion. However, attempts to correlate these predictions with in vivo measures of brain injury have not been published. This article reports an approach to and preliminary results from the correlation of subject-specific FE model-predicted regions of high strain associated with diagnosed concussion and diffusion tensor imaging to assess changes in white matter integrity in the corpus callosum (CC). Ten football and ice hockey players who wore instrumented helmets to record head impacts sustained during play completed high field magnetic resonance imaging preseason and within 10 days of a diagnosed concussion. The Dartmouth Subject-Specific FE Head model was used to generate regional predictions of strain and strain rate following each impact associated with concussion. Maps of change in fractional anisotropy (FA) and median diffusivity (MD) were generated for the CC of each athlete to correlate strain with change in FA and MD. Mean and maximum strain rate correlated with change in FA (Spearman ρ = 0.77, p = 0.01; 0.70, p = 0.031), and there was a similar trend for mean and maximum strain (0.56, p = 0.10; 0.6, p = 0.07), as well as for maximum strain with change in MD (−0.63, p = 0.07). Change in MD correlated with injury-to-imaging interval (ρ = −0.80, p = 0.006) but change in FA did not (ρ = 0.18, p = 0.62). These results provide preliminary confirmation that model-predicted strain and strain rate in the CC correlate with changes in indices of white matter integrity. PMID:21994062

  4. Radiologic Determination of Corpus Callosum Injury in Patients with Mild Traumatic Brain Injury and Associated Clinical Characteristics

    PubMed Central

    Kim, Dong Shin; Yang, Jin Seo; Cho, Yong Jun; Kang, Suk Hyung

    2015-01-01

    Objective To investigate the incidence of corpus callosum injury (CCI) in patients with mild traumatic brain injury (TBI) using brain MRI. We also performed a review of the clinical characteristics associated with this injury. Methods A total of 356 patients in the study were diagnosed with TBI, with 94 patients classified as having mild TBI. We included patients with mild TBI for further evaluation if they had normal findings via brain computed tomography (CT) scans and also underwent brain MRI in the acute phase following trauma. As assessed by brain MRI, CCI was defined as a high-signal lesion in T2 sagittal images and a corresponding low-signal lesion as determined by axial gradient echo (GRE) imaging. Based on these criteria, we divided patients into two groups for further analysis : Group I (TBI patients with CCI) and Group II (TBI patients without CCI). Results A total of 56 patients were enrolled in this study (including 16 patients in Group I and 40 patients in Group II). Analysis of clinical symptoms revealed a significant difference in headache severity between groups. Over 50% of patients in Group I experienced prolonged neurological symptoms including dizziness and gait disturbance and were more common in Group I than Group II (dizziness : 37 and 12% in Groups I and II, respectively; gait disturbance : 12 and 0% in Groups I and II, respectively). Conclusion The incidence of CCI in patients with mild TBI was approximately 29%. We suggest that brain MRI is a useful method to reveal the cause of persistent symptoms and predict clinical prognosis. PMID:26361529

  5. Metabolic levels in the corpus callosum and their structural and behavioral correlates after moderate to severe pediatric TBI.

    PubMed

    Babikian, Talin; Marion, Sarah Deboard; Copeland, Sarah; Alger, Jeffry R; O'Neill, Joseph; Cazalis, Fabienne; Mink, Richard; Giza, Christopher C; Vu, Jennifer A; Hilleary, Suzanne M; Kernan, Claudia L; Newman, Nina; Asarnow, Robert F

    2010-03-01

    Diffuse axonal injury (DAI) secondary to traumatic brain injury (TBI) contributes to long-term functional morbidity. The corpus callosum (CC) is particularly vulnerable to this type of injury. Magnetic resonance spectroscopy (MRS) was used to characterize the metabolic status of two CC regions of interest (ROIs) (anterior and posterior), and their structural (diffusion tensor imaging; DTI) and neurobehavioral (neurocognitive functioning, bimanual coordination, and interhemispheric transfer time [IHTT]) correlates. Two groups of moderate/severe TBI patients (ages 12-18 years) were studied: post-acute (5 months post-injury; n = 10), and chronic (14.7 months post-injury; n = 8), in addition to 10 age-matched healthy controls. Creatine (energy metabolism) did not differ between groups across both ROIs and time points. In the TBI group, choline (membrane degeneration/inflammation) was elevated for both ROIs at the post-acute but not chronic period. N-acetyl aspartate (NAA) (neuronal/axonal integrity) was reduced initially for both ROIs, with partial normalization at the chronic time point. Posterior, not anterior, NAA was positively correlated with DTI fractional anisotropy (FA) (r = 0.88), and most domains of neurocognition (r range 0.22-0.65), and negatively correlated with IHTT (r = -0.89). Inverse corerlations were noted between creatine and posterior FA (r = -0.76), neurocognition (r range -0.22 to -0.71), and IHTT (r = 0.76). Multimodal studies at distinct time points in specific brain structures are necessary to delineate the course of the degenerative and reparative processes following TBI, which allows for preliminary hypotheses about the nature and course of the neural mechanisms of subsequent functional morbidity. This will help guide the future development of targeted therapeutic agents. PMID:19925210

  6. Negative Associations between Corpus Callosum Midsagittal Area and IQ in a Representative Sample of Healthy Children and Adolescents

    PubMed Central

    Ganjavi, Hooman; Lewis, John D.; Bellec, Pierre; MacDonald, Penny A.; Waber, Deborah P.; Evans, Alan C.; Karama, Sherif

    2011-01-01

    Documented associations between corpus callosum size and cognitive ability have heretofore been inconsistent potentially owing to differences in sample characteristics, differing methodologies in measuring CC size, or the use of absolute versus relative measures. We investigated the relationship between CC size and intelligence quotient (IQ) in the NIH MRI Study of Normal Brain Development sample, a large cohort of healthy children and adolescents (aged six to 18, n = 198) recruited to be representative of the US population. CC midsagittal area was measured using an automated system that partitioned the CC into 25 subregions. IQ was measured using the Wechsler Abbreviated Scale of Intelligence (WASI). After correcting for total brain volume and age, a significant negative correlation was found between total CC midsagittal area and IQ (r = −0.147; p = 0.040). Post hoc analyses revealed a significant negative correlation in children (age<12) (r = −0.279; p = 0.004) but not in adolescents (age≥12) (r = −0.005; p = 0.962). Partitioning the subjects by gender revealed a negative correlation in males (r = −0.231; p = 0.034) but not in females (r = 0.083; p = 0.389). Results suggest that the association between CC and intelligence is mostly driven by male children. In children, a significant gender difference was observed for FSIQ and PIQ, and in males, a significant age-group difference was observed for FSIQ and PIQ. These findings suggest that the correlation between CC midsagittal area and IQ may be related to age and gender. PMID:21625542

  7. Corpus callosum area in patients with bipolar disorder with and without psychotic features: an international multicentre study

    PubMed Central

    Sarrazin, Samuel; d’Albis, Marc-Antoine; McDonald, Colm; Linke, Julia; Wessa, Michèle; Phillips, Mary; Delavest, Marine; Emsell, Louise; Versace, Amelia; Almeida, Jorge; Mangin, Jean-François; Poupon, Cyril; Le Dudal, Katia; Daban, Claire; Hamdani, Nora; Leboyer, Marion; Houenou, Josselin

    2015-01-01

    Background Previous studies have reported MRI abnormalities of the corpus callosum (CC) in patients with bipolar disorder (BD), although only a few studies have directly compared callosal areas in psychotic versus nonpsychotic patients with this disorder. We sought to compare regional callosal areas in a large international multicentre sample of patients with BD and healthy controls. Methods We analyzed anatomic T1 MRI data of patients with BD-I and healthy controls recruited from 4 sites (France, Germany, Ireland and the United States). We obtained the mid-sagittal areas of 7 CC subregions using an automatic CC delineation. Differences in regional callosal areas between patients and controls were compared using linear mixed models (adjusting for age, sex, handedness, brain volume, history of alcohol abuse/dependence, lithium or antipsychotic medication status, symptomatic status and site) and multiple comparisons correction. We also compared regional areas of the CC between patients with BD with and without a history of psychotic features. Results We included 172 patients and 146 controls in our study. Patients with BD had smaller adjusted mid-sagittal CC areas than controls along the posterior body, the isthmus and the splenium of the CC. Patients with a positive history of psychotic features had greater adjusted area of the rostral CC region than those without a history of psychotic features. Limitations We found small to medium effect sizes, and there was no calibration technique among the sites. Conclusion Our results suggest that BD with psychosis is associated with a different pattern of interhemispheric connectivity than BD without psychosis and could be considered a relevant neuroimaging subtype of BD. PMID:26151452

  8. Response inhibition deficits in children with Fetal Alcohol Spectrum Disorder: Relationship between diffusion tensor imaging of the corpus callosum and eye movement control

    PubMed Central

    Paolozza, Angelina; Treit, Sarah; Beaulieu, Christian; Reynolds, James N.

    2014-01-01

    Response inhibition is the ability to suppress irrelevant impulses to enable goal-directed behavior. The underlying neural mechanisms of inhibition deficits are not clearly understood, but may be related to white matter connectivity, which can be assessed using diffusion tensor imaging (DTI). The goal of this study was to investigate the relationship between response inhibition during the performance of saccadic eye movement tasks and DTI measures of the corpus callosum in children with or without Fetal Alcohol Spectrum Disorder (FASD). Participants included 43 children with an FASD diagnosis (12.3 ± 3.1 years old) and 35 typically developing children (12.5 ± 3.0 years old) both aged 7–18, assessed at three sites across Canada. Response inhibition was measured by direction errors in an antisaccade task and timing errors in a delayed memory-guided saccade task. Manual deterministic tractography was used to delineate six regions of the corpus callosum and calculate fractional anisotropy (FA), mean diffusivity (MD), parallel diffusivity, and perpendicular diffusivity. Group differences in saccade measures were assessed using t-tests, followed by partial correlations between eye movement inhibition scores and corpus callosum FA and MD, controlling for age. Children with FASD made more saccade direction errors and more timing errors, which indicates a deficit in response inhibition. The only group difference in DTI metrics was significantly higher MD of the splenium in FASD compared to controls. Notably, direction errors in the antisaccade task were correlated negatively to FA and positively to MD of the splenium in the control, but not the FASD group, which suggests that alterations in connectivity between the two hemispheres of the brain may contribute to inhibition deficits in children with FASD. PMID:24967159

  9. Association between reduced white matter integrity in the corpus callosum and serotonin transporter gene DNA methylation in medication-naive patients with major depressive disorder.

    PubMed

    Won, E; Choi, S; Kang, J; Kim, A; Han, K-M; Chang, H S; Tae, W S; Son, K R; Joe, S-H; Lee, M-S; Ham, B-J

    2016-01-01

    Previous evidence suggests that the serotonin transporter gene (SLC6A4) is associated with the structure of brain regions that are critically involved in dysfunctional limbic-cortical network activity associated with major depressive disorder (MDD). Diffusion tensor imaging (DTI) and tract-based spatial statistics were used to investigate changes in white matter integrity in patients with MDD compared with healthy controls. A possible association between structural alterations in white matter tracts and DNA methylation of the SLC6A4 promoter region was also assessed. Thirty-five medication-naive patients with MDD (mean age: 40.34, male/female: 10/25) and age, gender and education level matched 49 healthy controls (mean age: 41.12, male/female: 15/34) underwent DTI. SLC6A4 DNA methylation was also measured at five CpG sites of the promoter region, and the cell type used was whole-blood DNA. Patients with MDD had significantly lower fractional anisotropy (FA) values for the genu of the corpus callosum and body of the corpus callosum than that in healthy controls (family-wise error corrected, P<0.01). Significant inverse correlations were observed between SLC6A4 DNA methylation and FA (CpG3, Pearson's correlation: r=-0.493, P=0.003) and axial diffusivity (CpG3, Pearson's correlation: r=-0.478, P=0.004) values of the body of the corpus callosum in patients with MDD. These results contribute to evidence indicating an association between epigenetic gene regulation and structural brain alterations in depression. Moreover, we believe this is the first report of a correlation between DNA methylation of the SLC6A4 promoter region and white matter integrity in patients with MDD. PMID:27505229

  10. The gene responsible for a severe form of peripheral neuropathy and agenesis of the corpus callosum maps to chromosome 15q

    SciTech Connect

    Casaubon, L.K.; Melanson, M.; Marineau, C. |

    1996-01-01

    Peripheral neuropathy with or without agenesis of the corpus callosum (ACCPN) is a devastating neurodegenerative disorder that is transmitted as an autosomal recessive trait. Genealogical studies in a large number of affected French Canadian individuals suggest that ACCPN results from a single founder mutation. A genomewide search using 120 microsatellite DNA markers in 14 French Canadian families allowed the mapping of the ACCPN gene to a 5-cM region on chromosome 15q13-q15 that is flanked by markers D15S1040 and D15S118. A maximum two-point LOD score of 11.1 was obtained with the marker D15S971 at a recombination fraction of 0. Haplotype analysis and linkage disequilibrium support a founder effect. These findings are the first step in the identification of the gene responsible for ACCPN, which may shed some light on the numerous conditions associated with progressive peripheral neuropathy or agenesis of the corpus callosum. 28 refs., 2 figs., 3 tabs.

  11. Forced Abstinence from Cocaine Self-Administration is Associated with DNA Methylation Changes in Myelin Genes in the Corpus Callosum: a Preliminary Study

    PubMed Central

    Nielsen, David A.; Huang, Wen; Hamon, Sara C.; Maili, Lorena; Witkin, Brian M.; Fox, Robert G.; Cunningham, Kathryn A.; Moeller, F. Gerard

    2012-01-01

    Background: Human cocaine abuse is associated with alterations in white matter integrity revealed upon brain imaging, an observation that is recapitulated in an animal model of continuous cocaine exposure. The mechanism through which cocaine may affect white matter is unknown and the present study tested the hypothesis that cocaine self-administration results in changes in DNA methylation that could result in altered expression of several myelin genes that could contribute to the effects of cocaine on white matter integrity. Methods: In the present study, we examined the impact of forced abstinence from cocaine self-administration on chromatin associated changes in white matter. To this end, rats were trained to self-administer cocaine (0.75 mg/kg/0.1 mL infusion) for 14 days followed by forced abstinence for 1 day (n = 6) or 30 days (n = 6) before sacrifice. Drug-free, sham surgery controls (n = 7) were paired with the experimental groups. Global DNA methylation and DNA methylation at specific CpG sites in the promoter regions ofmyelin basic protein (Mbp), proteolipid protein-1 (Plp1), and SRY-related HMG-box-10 (Sox10) genes were analyzed in DNA extracted from corpus callosum. Results: Significant differences in the overall methylation patterns of the Sox10 promoter region were observed in the corpus callosum of rats at 30 days of forced abstinence from cocaine self-administration relative to sham controls; the −189, −142, −93, and −62 CpG sites were significantly hypomethylated point-wise at this time point. After correction for multiple comparisons, no differences in global methylation or the methylation patterns of Mbp or Plp1 were found. Conclusion: Forced abstinence from cocaine self-administration was associated with differences in DNA methylation at specific CpG sites in the promoter region of the Sox10 gene in corpus callosum. These changes may be related to reductions in normal age related changes in DNA methylation and

  12. Software pipeline for midsagittal corpus callosum thickness profile processing : automated segmentation, manual editor, thickness profile generator, group-wise statistical comparison and results display.

    PubMed

    Adamson, Chris; Beare, Richard; Walterfang, Mark; Seal, Marc

    2014-10-01

    This paper presents a fully automated pipeline for thickness profile evaluation and analysis of the human corpus callosum (CC) in 3D structural T 1-weighted magnetic resonance images. The pipeline performs the following sequence of steps: midsagittal plane extraction, CC segmentation algorithm, quality control tool, thickness profile generation, statistical analysis and results figure generator. The CC segmentation algorithm is a novel technique that is based on a template-based initialisation with refinement using mathematical morphology operations. The algorithm is demonstrated to have high segmentation accuracy when compared to manual segmentations on two large, publicly available datasets. Additionally, the resultant thickness profiles generated from the automated segmentations are shown to be highly correlated to those generated from the ground truth segmentations. The manual editing tool provides a user-friendly environment for correction of errors and quality control. Statistical analysis and a novel figure generator are provided to facilitate group-wise morphological analysis of the CC. PMID:24968872

  13. CXCL12/CXCR4 Axis Improves Migration of Neuroblasts Along Corpus Callosum by Stimulating MMP-2 Secretion After Traumatic Brain Injury in Rats.

    PubMed

    Mao, Weifeng; Yi, Xin; Qin, Jianbing; Tian, Meiling; Jin, Guohua

    2016-06-01

    To investigate the effect of CXCL12 on migration of neural precursor cells after traumatic brain injury (TBI). We randomly divided 48 rats into four groups: (1) the sham group, rats were performed craniotomy only, (2) the control group, saline were injected into the ipsilateral cortex after TBI, (3) the CXCL12 group, CXCL12 were injected into the ipsilateral cortex after TBI, and (4) the CXCL12 + AMD3100 group, CXCL12 and AMD3100 were mixed together and injected into the ipsilateral cortex after TBI. At 7 days after TBI, the brain tissues were subjected to immunofluorescent double-labeled staining with the antibodies of CXCR4/DCX, MMP-2/DCX, MMP-2/GFAP, MMP-2/NeuN. Western blot assay was used to measure the protein levels of MMP-2. Compared with the control group, the number of CXCR4/DCX and MMP-2 positive cells around the injured corpus callosum area were significantly increased in the CXCL12 treatment group. The area occupied by these cells expanded and the shape changed from chain distribution to radial. CXCL12 + AMD3100 treatment significantly decreased the number and distribution area of CXCR4/DCX and MMP-2 positive cells compared with the CXCL12 treatment and control group. The DCX positive cells could not form chain or radial distribution. The protein expressions of MMP-2 had the similar change trends as the results of immunofluorescent staining. MMP-2 could be secreted by DCX, GFAP and NeuN positive cells. CXCL12/CXCR4 axis can improve the migration of the neuroblasts along the corpus callosum by stimulating the MMP-2 secretion of different types of cells. PMID:26801174

  14. Reproducibility and optimization of in vivo human diffusion-weighted MRS of the corpus callosum at 3 T and 7 T.

    PubMed

    Wood, Emily T; Ercan, Ayse Ece; Branzoli, Francesca; Webb, Andrew; Sati, Pascal; Reich, Daniel S; Ronen, Itamar

    2015-08-01

    Diffusion-weighted MRS (DWS) of brain metabolites enables the study of cell-specific alterations in tissue microstructure by probing the diffusion of intracellular metabolites. In particular, the diffusion properties of neuronal N-acetylaspartate (NAA), typically co-measured with N-acetylaspartyl glutamate (NAAG) (NAA + NAAG = tNAA), have been shown to be sensitive to intraneuronal/axonal damage in pathologies such as stroke and multiple sclerosis. Lacking, so far, are empirical assessments of the reproducibility of DWS measures across time and subjects, as well as a systematic investigation of the optimal acquisition parameters for DWS experiments, both of which are sorely needed for clinical applications of the method. In this study, we acquired comprehensive single-volume DWS datasets of the human corpus callosum at 3 T and 7 T. We investigated the inter- and intra-subject variability of empirical and modeled diffusion properties of tNAA [D(avg) (tNAA) and D(model) (tNAA), respectively]. Subsequently, we used a jackknife-like resampling approach to explore the variance of these properties in partial data subsets reflecting different total scan durations. The coefficients of variation (C(V)) and repeatability coefficients (C(R)) for D(avg) (tNAA) and D(model) (tNAA) were calculated for both 3 T and 7 T, with overall lower variability in the 7 T results. Although this work is limited to the estimation of the diffusion properties in the corpus callosum, we show that a careful choice of diffusion-weighting conditions at both field strengths allows the accurate measurement of tNAA diffusion properties in clinically relevant experimental time. Based on the resampling results, we suggest optimized acquisition schemes of 13-min duration at 3T and 10-min duration at 7 T, whilst retaining low variability (C(V) ≈ 8%) for the tNAA diffusion measures. Power calculations for the estimation of D(model )(tNAA) and D(avg) (tNAA) based on the suggested schemes show that

  15. Structural integrity of the corpus callosum predicts long-term transfer of fluid intelligence-related training gains in normal aging.

    PubMed

    Wolf, Dominik; Fischer, Florian Udo; Fesenbeckh, Johanna; Yakushev, Igor; Lelieveld, Irene Maria; Scheurich, Armin; Schermuly, Ingrid; Zschutschke, Lisa; Fellgiebel, Andreas

    2014-01-01

    Although cognitive training usually improves cognitive test performance, the capability to transfer these training gains into respective or functionally related cognitive domains varies significantly. Since most studies demonstrate rather limited transfer effects in older adults, aging might be an important factor in transfer capability differences. This study investigated the transfer capability of logical reasoning training gains to a measure of Fluid Intelligence (Gf) in relation to age, general intelligence, and brain structural integrity as measured by diffusion tensor imaging. In a group of 41 highly educated healthy elderly, 71% demonstrated successful transfer immediately after a 4-week training session (i.e. short-term transfer). In a subgroup of 22% of subjects transfer maintained over a 3-month follow-up period (i.e. long-term transfer). While short-term transfer was not related to structural integrity, long-term transfer was associated with increased structural integrity in corpus and genu of the corpus callosum. Since callosal structural integrity was also related to age (in the present and foregoing studies), previously observed associations between age and transfer might be moderated by the structural integrity. Surprisingly, age was not directly associated with transfer in this study which could be explained by the multi-dependency of the structural integrity (modulating factors beside age, e.g. genetics). In this highly educated sample, general intelligence was not related to transfer suggesting that high intelligence is not sufficient for transfer in normal aging. Further studies are needed to reveal the interaction of transfer, age, and structural integrity and delineate mechanisms of age-dependent transfer capabilities. PMID:22965837

  16. Deletion of KCC3 in parvalbumin neurons leads to locomotor deficit in a conditional mouse model of peripheral neuropathy associated with agenesis of the corpus callosum.

    PubMed

    Ding, Jinlong; Delpire, Eric

    2014-11-01

    Hereditary motor and sensory neuropathy associated with agenesis of the corpus callosum (HMSN/ACC or ACCPN) is an autosomal recessive disease caused by the disruption of the SLC12A6 gene, which encodes the K-Cl cotransporter-3 (KCC3). A ubiquitous deletion of KCC3 in mice leads to severe locomotor deficits similar to ACCPN patients. However, the underlying pathological mechanism leading to the disease remains unclear. Even though a recent study suggests that the neuropathic features of ACCPN are mostly due to neuronal loss of KCC3, the specific cell type responsible for the disease is still unknown. Here we established four tissue specific KCC3 knockout mouse lines to explore the cell population origin of ACCPN. Our results showed that the loss of KCC3 in parvalbumin-positive neurons led to significant locomotor deficit, suggesting a crucial role of these neurons in the development of the locomotor deficit. Interestingly, mice in which KCC3 deletion was driven by the neuron-specific enolase (NSE) did not develop any phenotype. Furthermore, we demonstrated that nociceptive neurons targeted with Nav1.8-driven CRE and Schwann cells targeted with a desert hedgehog-driven CRE were not involved in the development of ACCPN. Together, these results establish that the parvalbumin-positive neuronal population is an important player in the pathogenic development of ACCPN. PMID:25116249

  17. Polymorphism within a Neuronal Activity-Dependent Enhancer of NgR1 Is Associated with Corpus Callosum Morphology in Humans

    PubMed Central

    Isobe, Masanori; Tanigaki, Kenji; Muraki, Kazue; Miyata, Jun; Takemura, Ariyoshi; Sugihara, Genichi; Takahashi, Hidehiko; Aso, Toshihiko; Fukuyama, Hidenao; Hazama, Masaaki; Murai, Toshiya

    2015-01-01

    The human Nogo-66 receptor 1 (NgR1) gene, also termed Nogo receptor 1 or reticulon 4 receptor (RTN4R) and located within 22q11.2, inhibits axonal growth and synaptic plasticity. Patients with the 22q11.2 deletion syndrome show multiple changes in brain morphology, with corpus callosum (CC) abnormalities being among the most prominent and frequently reported. Thus, we hypothesized that, in humans, NgR1 may be involved in CC formation. We focused on rs701428, a single nucleotide polymorphism of NgR1, which is associated with schizophrenia. We investigated the effects of the rs701428 genotype on CC structure in 50 healthy participants using magnetic resonance imaging. Polymorphism of rs701428 was associated with CC structural variation in healthy participants; specifically, minor A allele carriers had larger whole CC volumes and lower radial diffusivity in the central CC region compared with major G allele homozygous participants. Furthermore, we showed that the NgR1 3′ region, which contains rs701428, is a neuronal activity-dependent enhancer, and that the minor A allele of rs701428 is susceptible to regulation of enhancer activity by MYBL2. Our results suggest that NgR1 can influence the macro- and microstructure of the white matter of the human brain.

  18. Antisaccadic Eye Movements Are Correlated with Corpus Callosum White Matter Mean Diffusivity, Stroop Performance, and Symptom Burden in Mild Traumatic Brain Injury and Concussion

    PubMed Central

    Ting, Windsor Kwan-Chun; Schweizer, Tom A.; Topolovec-Vranic, Jane; Cusimano, Michael D.

    2016-01-01

    Antisaccades are thought to involve higher level inputs from neural centers involved in rapid eye movement inhibition and control. Previous work has demonstrated that performance on the antisaccade task can help in the assessment of injury in acute and/or chronic mild traumatic brain injury (mTBI). In this exploratory study, we performed cross-sectional and longitudinal comparisons of rapid eye movement, followed by correlations of antisaccade performance with assessments of symptom burden, diffusion tensor imaging, and a neuropsychological test of response inhibition. Significant deficits in antisaccade median latency, F(2, 31) = 3.65, p = 0.04 and prosaccade error mean duration, F(2, 31) = 3.63, p = 0.04 were found between patient groups and controls: the former was correlated with loss of white matter integrity in the splenium of the corpus callosum in acute mTBI, rho = 0.90, p = 0.0005. Furthermore, increased antisaccade median latency was also correlated with poor performance on an executive functioning task, r2 = 0.439, p = 0.03, and greater symptom burden, r2 = 0.480, p = 0.02 in the acute mTBI patients. Our preliminary research suggests that the antisaccade task could be useful as a neurological marker for mTBI and concussion, but more work is required. PMID:26834693

  19. Adult-Onset Deficiency in Growth Hormone and Insulin-Like Growth Factor-I Alters Oligodendrocyte Turnover in the Corpus Callosum

    PubMed Central

    Hua, Kun; Forbes, M. Elizabeth; Lichtenwalner, Robin J.; Sonntag, William E.; Riddle, David R.

    2009-01-01

    Growth hormone (GH) and insulin-like growth factor-I (IGF-I) provide trophic support during development and also appear to influence cell structure, function and replacement in the adult brain. Recent studies demonstrated effects of the GH/IGF-I axis on adult neurogenesis, but it is unclear whether the GH/IGF-I axis influences glial turnover in the normal adult brain. In the current study we used a selective model of adult-onset GH and IGF-I deficiency to evaluate the role of GH and IGF-I in regulating glial proliferation and survival in the adult corpus callosum. GH/IGF-I-deficient dwarf rats of the Lewis strain were made GH/IGF-I replete via twice daily injections of GH starting at postnatal day 28 (P28), approximately the age at which GH pulse amplitude increases in developing rodents. GH/IGF-I deficiency was initiated in adulthood by removing animals from GH treatment. Quantitative analyses revealed that adult-onset GH/IGF-I deficiency decreased cell proliferation in the white matter and decreased the survival of newborn oligodendrocytes. These findings are consistent with the hypothesis that aging-related changes in the GH/IGF-I axis produce deficits in ongoing turnover of oligodendrocytes, which may contribute to aging-related cognitive changes and deficits in remyelination after injury. PMID:19115393

  20. 3D pre- versus post-season comparisons of surface and relative pose of the corpus callosum in contact sport athletes

    NASA Astrophysics Data System (ADS)

    Lao, Yi; Gajawelli, Niharika; Haas, Lauren; Wilkins, Bryce; Hwang, Darryl; Tsao, Sinchai; Wang, Yalin; Law, Meng; Leporé, Natasha

    2014-03-01

    Mild traumatic brain injury (MTBI) or concussive injury affects 1.7 million Americans annually, of which 300,000 are due to recreational activities and contact sports, such as football, rugby, and boxing[1]. Finding the neuroanatomical correlates of brain TBI non-invasively and precisely is crucial for diagnosis and prognosis. Several studies have shown the in influence of traumatic brain injury (TBI) on the integrity of brain WM [2-4]. The vast majority of these works focus on athletes with diagnosed concussions. However, in contact sports, athletes are subjected to repeated hits to the head throughout the season, and we hypothesize that these have an influence on white matter integrity. In particular, the corpus callosum (CC), as a small structure connecting the brain hemispheres, may be particularly affected by torques generated by collisions, even in the absence of full blown concussions. Here, we use a combined surface-based morphometry and relative pose analyses, applying on the point distribution model (PDM) of the CC, to investigate TBI related brain structural changes between 9 pre-season and 9 post-season contact sport athlete MRIs. All the data are fed into surface based morphometry analysis and relative pose analysis. The former looks at surface area and thickness changes between the two groups, while the latter consists of detecting the relative translation, rotation and scale between them.

  1. Corpus callosum atrophy as a predictor of age-related cognitive and motor impairment: a 3-year follow-up of the LADIS study cohort.

    PubMed

    Ryberg, C; Rostrup, E; Paulson, O B; Barkhof, F; Scheltens, P; van Straaten, E C W; van der Flier, W M; Fazekas, F; Schmidt, R; Ferro, J M; Baezner, H; Erkinjuntti, T; Jokinen, H; Wahlund, L-O; Poggesi, A; Pantoni, L; Inzitari, D; Waldemar, G

    2011-08-15

    The aim of this 3-year follow-up study was to investigate whether corpus callosum (CC) atrophy may predict future motor and cognitive impairment in an elderly population. On baseline MRI from 563 subjects with age-related white matter changes (ARWMC) from the Leukoaraiosis And DISability (LADIS) study, the CC was segmented and subdivided into five anterior-posterior regions (CC1-CC5). Associations between the CC areas and decline in motor performance and cognitive functions over a 3-year period were analyzed. CC atrophy at baseline was significantly associated with impaired cognitive performance (p<0.01 for CC1, p<0.05 for CC5), motor function (p<0.05 for CC2 and CC5), and walking speed (p<0.01 for CC2 and CC5, p<0.05 for CC3 and total CC), and with development of dementia at 3 years (p<0.05 for CC1) after correction for appropriate confounders (ARWMC volume, atrophy, age, gender and handedness). In conclusion, CC atrophy, an indicator of reduced functional connectivity between cortical areas, seems to contribute, independently of ARWMC load, to future cognitive and motor decline in the elderly. PMID:21621224

  2. Relationship between Stereoscopic Vision, Visual Perception, and Microstructure Changes of Corpus Callosum and Occipital White Matter in the 4-Year-Old Very Low Birth Weight Children

    PubMed Central

    Kwinta, Przemko; Herman-Sucharska, Izabela; Leśniak, Anna; Klimek, Małgorzata; Karcz, Paulina; Durlak, Wojciech; Nitecka, Magdalena; Dutkowska, Grażyna; Kubatko-Zielińska, Anna; Romanowska-Dixon, Bożena; Pietrzyk, Jacek Józef

    2015-01-01

    Aim. To assess the relationship between stereoscopic vision, visual perception, and microstructure of the corpus callosum (CC) and occipital white matter, 61 children born with a mean birth weight of 1024 g (SD 270 g) were subjected to detailed ophthalmologic evaluation, Developmental Test of Visual Perception (DTVP-3), and diffusion tensor imaging (DTI) at the age of 4. Results. Abnormal stereoscopic vision was detected in 16 children. Children with abnormal stereoscopic vision had smaller CC (CC length: 53 ± 6 mm versus 61 ± 4 mm; p < 0.01; estimated CC area: 314 ± 106 mm2 versus 446 ± 79 mm2; p < 0.01) and lower fractional anisotropy (FA) values in CC (FA value of rostrum/genu: 0.7 ± 0.09 versus 0.79 ± 0.07; p < 0.01; FA value of CC body: 0.74 ± 0.13 versus 0.82 ± 0.09; p = 0.03). We found a significant correlation between DTVP-3 scores, CC size, and FA values in rostrum and body. This correlation was unrelated to retinopathy of prematurity. Conclusions. Visual perceptive dysfunction in ex-preterm children without major sequelae of prematurity depends on more subtle changes in the brain microstructure, including CC. Role of interhemispheric connections in visual perception might be more complex than previously anticipated. PMID:26451381

  3. Ruptured aneurysm at the origin of the median artery of the corpus callosum associated with accessory middle cerebral artery--case report.

    PubMed

    Yanaka, K; Shirai, S; Shibata, Y; Nose, T

    2000-10-01

    A 62-year-old male presented with ruptured anterior communicating artery (ACoA) aneurysm manifesting as severe headache associated with the rare combination of median artery of the corpus callosum (MACC) and accessory middle cerebral artery (MCA). Computed tomography demonstrated diffuse subarachnoid hemorrhage. Left carotid angiography demonstrated an anomalous vessel originating from the ACoA complex and passing forward in the interhemispheric fissure between the two companion A2 segments. This vessel was identified as the MACC. Another anomalous vessel originated from the left A1-A2 segment and passed into the sylvian fissure. This vessel was identified as the accessory MCA. Left frontotemporal craniotomy was performed to clip the neck of the aneurysm. After identifying both A1 and A2 segments, accessory MCA, and the MACC, the aneurysm neck was occluded successfully. The ACoA complex is one of the most frequent sites of vascular anomalies. Preoperative and intraoperative care is required to identify the presence of anomalies of the ACoA complex prior to clip placement, to avoid accidental damage or clipping, which may result in severe neurological deficits. PMID:11098636

  4. Calcium, potassium, iron, copper and zinc concentrations in the white and gray matter of the cerebellum and corpus callosum in brain of four genetic mouse strains

    NASA Astrophysics Data System (ADS)

    Sergeant, C.; Vesvres, M. H.; Devès, G.; Guillou, F.

    2005-04-01

    In the central nervous system, metallic cations are involved in oligodendrocyte maturation and myelinogenesis. Moreover, the metallic cations have been associated with pathogenesis, particularly multiple sclerosis and malignant gliomas. The brain is vulnerable to either a deficit or an excess of available trace elements. Relationship between trace metals and myelinogenesis is important in understanding a severe human pathology : the multiple sclerosis, which remains without efficient treatment. One approach to understand this disease has used mutant or transgenic mice presenting myelin deficiency or excess. But to date, the concentration of trace metals and mineral elements in white and gray matter areas in wild type brain is unknown. The aim of this study is to establish the reference concentrations of trace metals (iron, copper and zinc) and minerals (potassium and calcium) in the white and gray matter of the mouse cerebellum and corpus callosum. The brains of four different genetic mouse strains (C57Black6/SJL, C57Black6/D2, SJL and C3H) were analyzed. The freeze-dried samples were prepared to allow PIXE (Proton-induced X-ray emission) and RBS (Rutherford backscattering spectrometry) analyses with the nuclear microprobe in Bordeaux. The results obtained give the first reference values. Furthermore, one species out of the fours testes exhibited differences in calcium, iron and zinc concentrations in the white matter.

  5. IMPACT OF EARLY AND LATE VISUAL DEPRIVATION ON THE STRUCTURE OF THE CORPUS CALLOSUM: A STUDY COMBINING THICKNESS PROFILE WITH SURFACE TENSOR-BASED MORPHOMETRY

    PubMed Central

    Shi, Jie; Collignon, Olivier; Xu, Liang; Wang, Gang; Kang, Yue; Leporé, Franco; Lao, Yi; Joshi, Anand A.

    2015-01-01

    Blindness represents a unique model to study how visual experience may shape the development of brain organization. Exploring how the structure of the corpus callosum (CC) reorganizes ensuing visual deprivation is of particular interest due to its important functional implication in vision (e.g. via the splenium of the CC). Moreover, comparing early versus late visually deprived individuals has the potential to unravel the existence of a sensitive period for reshaping the CC structure. Here, we develop a novel framework to capture a complete set of shape differences in the CC between congenitally blind (CB), late blind (LB) and sighted control (SC) groups. The CCs were manually segmented from T1-weighted brain MRI and modeled by 3D tetrahedral meshes. We statistically compared the combination of local area and thickness at each point between subject groups. Differences in area are found using surface tensor-based morphometry; thickness is estimated by tracing the streamlines in the volumetric harmonic field. Group differences were assessed on this combined measure using Hotelling’s T2 test. Interestingly, we observed that the total callosal volume did not differ between the groups. However, our fine-grained analysis reveals significant differences mostly localized around the splenium areas between both blind groups and the sighted group (general effects of blindness) and, importantly, specific dissimilarities between the LB and CB groups, illustrating the existence of a sensitive period for reorganization. The new multivariate statistics also gave better effect sizes for detecting morphometric differences, relative to other statistics. They may boost statistical power for CC morphometric analyses. PMID:25649876

  6. Agenesis of the Corpus Callosum

    MedlinePlus

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  7. Syndrome of absent abdominal muscles: two cases with microcephaly, polymicrogyria, and cerebellar malformations

    PubMed Central

    Heffner, Reid R.

    1970-01-01

    Two unique cases of the syndrome of absent abdominal muscles with central nervous system involvement are presented. Microcephaly, polymicrogyria, and cerebellar heterotopiae were present in both. In case 1 there was also absence of the corpus callosum and agenesis of the cerebellar vermis. In case 2 a count of anterior horn cells in the spinal cord showed a reduction of approximately 50% in the lower thoracic region. The pertinent literature is briefly discussed. The findings in the nervous system suggest that the syndrome is the result of defective embryogenesis during the first trimester. Images PMID:4250700

  8. Corpus Callosum Morphology in Children Who Stutter

    ERIC Educational Resources Information Center

    Choo, Ai Leen; Chang, Soo-Eun; Zengin-Bolatkale, Hatun; Ambrose, Nicoline G.; Loucks, Torrey M.

    2012-01-01

    Multiple studies have reported both functional and neuroanatomical differences between adults who stutter and their normally fluent peers. However, the reasons for these differences remain unclear although some developmental data suggest that structural brain differences may be present in school-age children who stutter. In the present study, the…

  9. Absent pulmonary valve

    MedlinePlus

    ... can occur with absent pulmonary valve include: Abnormal tricuspid valve Atrial septal defect Double outlet right ventricle Ductus arteriosis Endocardial cushion defect Marfan syndrome Tricuspid atresia Heart problems that occur with absent pulmonary ...

  10. Absent pulmonary valve

    MedlinePlus

    ... absent pulmonary valve syndrome associated with bronchial obstruction. Ann Thoracic Surg. 2006;82:2221-2226. PMID: 17126138 ... of airway compression in absent pulmonary valve syndrome. Ann Thorac Surg . 2006;81:1802-1807. PMID: 16631676 ...

  11. Prosody Meets Syntax: The Role of the Corpus Callosum

    ERIC Educational Resources Information Center

    Sammler, Daniela; Kotz, Sonja A.; Eckstein, Korinna; Ott, Derek V. M.; Friederici, Angela D.

    2010-01-01

    Contemporary neural models of auditory language comprehension proposed that the two hemispheres are differently specialized in the processing of segmental and suprasegmental features of language. While segmental processing of syntactic and lexical semantic information is predominantly assigned to the left hemisphere, the right hemisphere is…

  12. Tooth formation - delayed or absent

    MedlinePlus

    Delayed or absent tooth formation; Teeth - delayed or absent formation ... The age at which the tooth comes in varies. Most infants get their first tooth between 6 and 9 months, but it may be earlier or later. ...

  13. Age-related decline in the microstructural integrity of white matter in children with early- and continuously-treated PKU: A DTI study of the corpus callosum☆

    PubMed Central

    White, Desiree A.; Connor, Lisa Tabor; Nardos, Binyam; Shimony, Joshua S.; Archer, Rebecca; Snyder, Abraham Z.; Moinuddin, Asif; Grange, Dorothy K.; Steiner, Robert D.; McKinstry, Robert C.

    2013-01-01

    Structural, volumetric, and microstructural abnormalities have been reported in the white matter of the brain in individuals with phenylketonuria (PKU). Very little research, however, has been conducted to investigate the development of white matter in children with PKU, and the developmental trajectory of their white matter microstructure is unknown. In the current study, diffusion tensor imaging (DTI) was used to examine the development of the microstructural integrity of white matter across six regions of the corpus callosum in 34 children (7–18 years of age) with early- and continuously-treated PKU. Comparison was made with 61 demographically-matched healthy control children. Two DTI variables were examined: mean diffusivity (MD) and relative anisotropy (RA). RA was comparable to that of controls across all six regions of the corpus callosum. In contrast, MD was restricted for children with PKU in anterior (i.e., genu, rostral body, anterior midbody) but not posterior (posterior midbody, isthmus, splenium) regions of the corpus callosum. In addition, MD restriction became more pronounced with increasing age in children with PKU in the two most anterior regions of the corpus callosum (i.e., genu, rostral body). These findings point to an age-related decrement in the microstructural integrity of the anterior white matter of the corpus callosum in children with PKU. PMID:20123469

  14. Corpus Christi, Texas

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This near vertical view of the south Texas coast shows the city of Corpus Christi (28.0N, 97.0W) and Corpus Christi Bay. Mustang Island and the Gulf of Mexico are seen in the Southeast corner of the view. The Nueces River flows into the bay from the west. The light toned squiggly lines in Corpus Christi Bay are mud trails caused by shrimp boats dragging their nets along the shallow bottom of the bay.

  15. Corpus callosotomy: some aspects of its microsurgical anatomy.

    PubMed

    Gonçalves Ferreira, A J; Farias, J P; Carvalho, M H; Melancia, J; Miguéns, J

    1995-01-01

    Corpus callosotomy was reported for the first time by Dandy in 1922 and developed by Van Wagenen and Herren in 1940, but only Wilson in 1975 started performing it with a microsurgical technique. Its indications have remained controversial for a long time, but during the last years new interest has been raised concerning callosotomy as a treatment for some kinds of generalized epilepsy or as route to the anterior ventricular system. The microsurgical anatomy of the corpus callosum has therefore regained interest. With this goal in mind, the authors studied some aspects of the microsurgical anatomy of the corpus callosum, namely its dimensions, variability and topography, as well as the transcallosal access to the deep interfrontal region and to the third ventricle. This study was carried out on 30 normal adult brains, obtained from routine autopsies, that were submitted to a special preparation procedure and dissected with microsurgical technique. The main aspects of the operating features, the measurements made and the variation in the different parameters are described. Some references are proposed respecting the extent of anterior partial and subtotal callosotomy. PMID:8916335

  16. Developing Software for Corpus Research

    ERIC Educational Resources Information Center

    Mason, Oliver

    2008-01-01

    Despite the central role of the computer in corpus research, programming is generally not seen as a core skill within corpus linguistics. As a consequence, limitations in software for text and corpus analysis slow down the progress of research while analysts often have to rely on third party software or even manual data analysis if no suitable…

  17. Isolated and reversible lesions of the corpus callosum: a distinct entity.

    PubMed

    Garcia-Monco, Juan Carlos; Martínez, Amaia; Brochado, Ana Pinedo; Saralegui, Ibone; Cabrera, Alberto; Beldarrain, Marian Gomez

    2010-01-01

    The Reversible Splenial Lesion Syndrome represents a distinct clinicoradiological syndrome, associated with several disorders, including infection, high altitude cerebral edema, antiepileptic drug withdrawal, and severe metabolic disturbances (hypoglycemia and hypernatremia). Clinical presentation is nonspecific, most frequently as an encephalopathy or encephalitis. Outcome is favorable in most patients unless there is a severe underlying disorder. Magnetic resonance imaging findings are restricted to the splenium and consist of a nonenhancing oval lesion, hyperintense on T2-weighted images, including FLAIR. Findings on diffusion-weighted imaging are consistent with cytotoxic edema except for high-altitude cerebral edema, where vasogenic edema is present. Resolution after weeks or months is the rule. PMID:19747237

  18. DEVELOPMENTAL HYPOTHYROIDISM INDUCES A NEURONAL HETEROTOPIA IN THE CORPUS CALLOSUM OF THE RAT.

    EPA Science Inventory

    It is well established that severe hypothyroidism leads to profound alterations in brain development and mental retardation. In this study we examined the effect of subtle decreases in maternal thyroid hormones (TH) on brain development in the rat. To induce TH insufficiency pr...

  19. Reduced Gyral Window and Corpus Callosum Size in Autism: Possible Macroscopic Correlates of a Minicolumnopathy

    ERIC Educational Resources Information Center

    Casanova, Manuel F.; El-Baz, Ayman; Mott, Meghan; Mannheim, Glenn; Hassan, Hossam; Fahmi, Rachid; Giedd, Jay; Rumsey, Judith M.; Switala, Andrew E.; Farag, Aly

    2009-01-01

    Minicolumnar changes that generalize throughout a significant portion of the cortex have macroscopic structural correlates that may be visualized with modern structural neuroimaging techniques. In magnetic resonance images (MRIs) of fourteen autistic patients and 28 controls, the present study found macroscopic morphological correlates to recent…

  20. Microstructural Integrity of the Corpus Callosum Linked with Neuropsychological Performance in Adolescents

    ERIC Educational Resources Information Center

    Fryer, Susanna L.; Frank, Lawrence R.; Spadoni, Andrea D.; Theilmann, Rebecca J.; Nagel, Bonnie J.; Schweinsburg, Alecia D.; Tapert, Susan F.

    2008-01-01

    Background: Diffusion tensor imaging (DTI) has revealed microstructural aspects of adolescent brain development, the cognitive correlates of which remain relatively uncharacterized. Methods: DTI was used to assess white matter microstructure in 18 typically developing adolescents (ages 16-18). Fractional anisotropy (FA) and mean diffusion (MD)…

  1. The Association of Macro- and Microstructure of the Corpus Callosum and Language Lateralisation

    ERIC Educational Resources Information Center

    Westerhausen, Rene; Kreuder, Frank; Sequeira, Sarah Dos Santos; Walter, Christof; Woerner, Wolfgang; Wittling, Ralf Arne; Schweiger, Elisabeth; Wittling, Werner

    2006-01-01

    The present study aimed to examine how differences in functional lateralisation of language are related to interindividual variations in interhemispheric connectivity. Utilising an fMRI silent word-generation paradigm, 89 left- and right-handed subjects were subdivided into four lateralisation subgroups. Applying morphological and diffusion-tensor…

  2. Diffusion tensor imaging, white matter lesions, the corpus callosum, and gait in the elderly

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gait impairment is common in the elderly, especially affected by stroke and white matter hyper intensities found in conventional brain magnetic resonance imaging (MRI). Diffusion tensor imaging (DTI) is more sensitive to white matter damage than conventional MRI. The relationship between DTI measure...

  3. "Thoughts across My Corpus Callosum": What Lewis Thomas's Essays Can Teach Students about Writing Well.

    ERIC Educational Resources Information Center

    White, Fred D.

    As Lewis Thomas has maintained, much of today's public anxiety about science is the apprehension that the whole is being overlooked by an endless, obsessive preoccupation with the parts, and this is a suitable analogy for composition teaching. Students and teachers alike tend to fret endlessly over minute details of writing, like grammar,…

  4. Letter regarding article 'Freezing of gait associated with a corpus callosum lesion'.

    PubMed

    Onder, Halil

    2016-01-01

    Here, I discuss the report by Dale et al. and present some relevant comments, hoping that it will allow a better understanding of the patient's situation as well as freezing of gait phenomenon. I will also discuss other disorders for differential diagnosis those should be kept in mind. PMID:27617107

  5. Infants Interpret Ambiguous Requests for Absent Objects

    ERIC Educational Resources Information Center

    Saylor, Megan M.; Ganea, Patricia

    2007-01-01

    The current studies investigated 2 skills involved in 14- to 20-month-olds' ability to interpret ambiguous requests for absent objects: tracking others' experiences (Study 1) and representing links between speakers and object features across present and absent reference episodes (Study 2). In the basic task, 2 experimenters played separately with…

  6. Surgical Management of Absent Pulmonary Valve Syndrome.

    PubMed

    Jonas, Richard A

    2016-09-01

    The author's approach to the management of tetralogy of Fallot with absent pulmonary valve is described, including the technique of homograft replacement of the central pulmonary arteries for the neonate who presents with profound respiratory compromise. PMID:27587495

  7. Corpus callosal microstructure influences intermanual transfer in chimpanzees

    PubMed Central

    Phillips, Kimberley A.; Schaeffer, Jennifer A.; Hopkins, William D.

    2013-01-01

    Learning a new motor skill with one hand typically results in performance improvements in the alternate hand. The neural substrates involved with this skill acquisition are poorly understood. We combined behavioral testing and non-invasive brain imaging to study how the organization of the corpus callosum was related to intermanual transfer performance in chimpanzees. Fifty-three chimpanzees were tested for intermanual transfer of learning using a bent-wire task. Magnetic resonance and diffusion tensor images were collected from 39 of these subjects. The dominant hand showed greater performance benefits than the nondominant hand. Further, performance was associated with structural integrity of the motor and sensory regions of the CC. Subjects with better intermanual transfer of learning had lower fractional anisotropy values. The results are consistent with the callosal access model of motor programming. PMID:24427118

  8. [Corpus Hermeticum in history].

    PubMed

    Bugaj, R

    2001-01-01

    The originator and founder of hermetism was the mythical Hermes Trismegistos, a deity of the syncretic Hellenistic religion that came into being through the identification of the Greek god Hermes with the Egyptian god Thot. In later Hellenistsic times various hermetic writers considered Hermes Trismegistos to have been a historical personage, a king, prophet and philosopher (physician), as well as author of many widely disseminated writings that made up the so-called Corpus Hermeticum (eighteen separate treatises from the 2nd-4th centuries AD) and the so-called Emerald Table (Tabula Smaragdina). The Corpus Hermeticum is a collection of treatises of a philosophical, religious, theological as well as theosophical nature. The collection played an important role in the development of the philosophy of alchemy and hermetism, and formed the basis for an alchemist philosophy of nature. There are currently two views among scholars on the origins of hermetism. According to one, hermetism derived directly from Egypt, while according to the other it orginated in Greece. In the years 1945-46 a number of hermetic texts forming part of the now famous gnostic "library" were discovered in Nag-Hammadi (Chenosboskion) in Upper Egypt. The Coptic texts from Nag-Hammadi date from the middle of the 4th century AD, and according to experts are translations from the Greek. Some authors (R. Reitzenstein and T. Zieliński) have suggested that along with the appearance in Egypt of the Hermetic Books, attributed to Hermes Trismegistos, there also appeared a new god in Egypt, Poimandres, and a new religion was established, hermetism, which competed for influence with Christianity. The present article discusses the main of the hermetic treatises, including Poimandres, which contains an account of the creation of the world. The article also discusses the reasons for the decline of hermetism as a religion and stresses that in spite of this decline the doctrine managed to survive in the form of

  9. Omphalocele major with absent lower limb.

    PubMed

    Kundal, Vijay Kumar; Gajdhar, Mufique; Kundal, Raksha; Ahmed, Reyaz; Agrawal, Leela Dhar

    2015-02-01

    A newborn delivered by Caesarian section presented with an absent anterior abdominal wall and visible bowel loops and liver. The defect was covered by a thin membrane. The patient had associated absent left lower limb and right foot fusion defect. The patient was haemodynamically stable; general condition was average. No genito-urinary abnormality was detected. The anal opening was present normally, and the patient passed meconium immediately after birth. A diagnosis of omphalocele major with amelia was made. The patient was initially managed by topical application of povidone-iodine for eschar formation and epithelisation of the sac. The patient was discharged after 1 week with advice for regular follow-up. PMID:25829718

  10. Allograft Replacement for Absent Native Tissue

    PubMed Central

    Chaudhury, Salma; Wanivenhaus, Florian; Fox, Alice J.; Warren, Russell F.; Doyle, Maureen; Rodeo, Scott A.

    2013-01-01

    Context: Structural instability due to poor soft tissue quality often requires augmentation. Allografts are important biological substitutes that are used for the symptomatic patient in the reconstruction of deficient ligaments, tendons, menisci, and osteochondral defects. Interest in the clinical application of allografts has arisen from the demand to obtain stable anatomy with restoration of function and protection against additional injury, particularly for high-demand patients who participate in sports. Traditionally, allografts were employed to reinforce weakened tissue. However, they can also be employed to substitute deficient or functionally absent tissue, particularly in the sports medicine setting. Objective: This article presents a series of 6 cases that utilized allografts to restore functionally deficient anatomic architecture, rather than just simply augmenting the degenerated or damaged native tissue. Detailed discussions are presented of the use of allografts as a successful treatment strategy to replace functionally weakened tissue, often after failed primary repairs. PMID:24427387

  11. Corpus-based Customization for an Ontology

    2010-09-14

    CCAT scans a corpus of text for terms, and computes lexical similarity between corpus terms and taxonomy terms. Based on a set of metrics and a learning algorithm, the system inserts corpus terms into the taxonomy. Conversely, terms from the taxonomy are disambiguated based on the text in the corpus. Unused terms are discarded, and infrequently used senses of terms are collapsed to make the taxonomy more manageable.

  12. Semen searching when sperm is absent.

    PubMed

    Martínez, Pilar; Santiago, Begoña; Alcalá, Belén; Atienza, Inmaculada

    2015-03-01

    Sexual assault cases have varying factors that may mask semen findings when analysing evidence at the forensic laboratory. Semenogelin (Sg) is a potential marker for the identification of semen even at azoospermy or when few sperm cells are found. The current study examined Sg in normospermic and azoospermic donors as an internal evaluation of sensitivity, specificity and interference. The impact of a historical review of 53 judicial sexual assault cases over a five-year period was also analysed. The use of varying tests was of importance to prioritize certain samples within cases. Semen findings by Sg were then compared to prostate-specific antigen (PSA), phosphatase enzyme (AP) and Y-chromosome presence, the latter being used in an attempt to link semen fluid identification with obtaining a male DNA profile. Test findings were the highest ever registered for Sg (1:400,000), PSA (1:800,000), AP (1:25,000) and sperm cytology (SC) (1:50,000). Our results demonstrated the usefulness of using the Sg marker to avoid a false semen-negative result (6% cases), particularly in cases where sperm was absent or scarce (11% spermatozoa positive cases). Results were expressed in categories according to the set: Sg-PSA-AP. Thus, categories I (full positive, 46%), VI (full negative, 27%) and III (Sg/PSA positive; 11%) were the most frequent and Y-chromosome was obtained in 59%, 12% and 12% ratios, respectively. In conclusion, Sg was recommended for the workflow procedure of semen investigation when sperm absence is expected either from azoospermic/oligospermic or normospermic semen, especially before/after ejaculation. PMID:25753997

  13. Corpus Christi oil port eyed

    SciTech Connect

    Powers, M.B.

    1993-07-05

    The Port of Corpus Christi, Texas, with the support of several oil companies and the blessing of the US Coast Guard, plans to build a $600-million deepwater harbor to accommodate supertankers. The proposed port, Safeharbor, is touted as an environmentally sound solution to current risks associated with off-loading crude oil from very large tankers at shore ports. In a system called lightering, crude now is transferred from supertankers in deep water to smaller vessels that can negotiate shallow channels. While smaller tankers need only 45 ft of water, supertankers need 80 ft. Corpus Christi has the advantage of being closer to deep water than other Gulf ports, but nevertheless, half the proposed project's cost, $300 million, would be for dredging a 10-mile channel to deep water.

  14. Idiom Comprehension Deficits in Relation to Corpus Callosum Agenesis and Hypoplasia in Children with Spina Bifida Meningomyelocele

    ERIC Educational Resources Information Center

    Huber-Okrainec, J.; Blaser, S.E.; Dennis, M.

    2005-01-01

    Idioms are phrases with figurative meanings that are not directly derived from the literal meanings of the words in the phrase. Idiom comprehension varies with: literality, whether the idiom is literally plausible; compositionality, whether individual words contribute to a figurative meaning; and contextual bias. We studied idiom comprehension in…

  15. Amygdala, Hippocampal and Corpus Callosum Size Following Severe Early Institutional Deprivation: The English and Romanian Adoptees Study Pilot

    ERIC Educational Resources Information Center

    Mehta, Mitul A.; Golembo, Nicole I.; Nosarti, Chiara; Colvert, Emma; Mota, Ashley; Williams, Steven C. R.; Rutter, Michael; Sonuga-Barke, Edmund J. S.

    2009-01-01

    The adoption into the UK of children who have been reared in severely deprived conditions provides an opportunity to study possible association between very early negative experiences and subsequent brain development. This cross-sectional study was a pilot for a planned larger study quantifying the effects of early deprivation on later brain…

  16. MODEST THYROID HORMONE INSUFFICIENCY DURING DEVELOPMENT INDUCES A CELLULAR MALFORMATION IN THE CORPUS CALLOSUM: A MODEL OF CORTICAL DYSPLASIA.

    EPA Science Inventory

    There is a growing body of evidence that subtle decreases in maternal thyroid hormone during gestation can impact fetal brain development. The present study examined the impact of graded levels of thyroid hormone insufficiency on brain development in rodents. Maternal thyroid ho...

  17. Absent Aortic Valve in DiGeorge Syndrome.

    PubMed

    Bertsch, Elizabeth C; Minturn, Lucy; Gotteiner, Nina L; Ernst, Linda M

    2016-01-01

    A 20-week-old fetus with the 22q11.2 deletion characteristic of DiGeorge syndrome is described with vertebral segmentation abnormalities and complex cardiovascular anomalies including an absent aortic valve. This is only the second known case of absent aortic valve in association with DiGeorge syndrome. We discuss the association of absent aortic valve with other conotruncal defects and the utility of fetal echocardiography in the diagnosis of DiGeorge syndrome. PMID:26230226

  18. 33 CFR 165.808 - Corpus Christi Ship Channel, Corpus Christi, TX, safety zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CFR 165.23 apply. (c) The Captain of the Port will notify the maritime community of periods during... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Corpus Christi Ship Channel... § 165.808 Corpus Christi Ship Channel, Corpus Christi, TX, safety zone. (a) The following areas...

  19. 33 CFR 165.808 - Corpus Christi Ship Channel, Corpus Christi, TX, safety zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CFR 165.23 apply. (c) The Captain of the Port will notify the maritime community of periods during... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Corpus Christi Ship Channel... § 165.808 Corpus Christi Ship Channel, Corpus Christi, TX, safety zone. (a) The following areas...

  20. 32 CFR 516.20 - Habeas Corpus.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 3 2011-07-01 2009-07-01 true Habeas Corpus. 516.20 Section 516.20 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY AID OF CIVIL AUTHORITIES AND PUBLIC RELATIONS LITIGATION Reporting Legal Proceedings to HQDA § 516.20 Habeas Corpus. (a) General. A soldier...

  1. Enriching Language Learning through a Multimedia Corpus

    ERIC Educational Resources Information Center

    Ackerley, Katherine; Coccetta, Francesca

    2007-01-01

    Until recently, use has been made almost exclusively of text-based concordancers in the analysis of spoken corpora. This article discusses research being carried out on Padua University's Multimedia English Corpus (Padova MEC) using the multimodal concordancer "MCA "("Multimodal Corpus Authoring System," Baldry, 2005). This highly innovative…

  2. Network Analysis with the Enron Email Corpus

    ERIC Educational Resources Information Center

    Hardin, J. S.; Sarkis, G.; URC, P. .

    2015-01-01

    We use the Enron email corpus to study relationships in a network by applying six different measures of centrality. Our results came out of an in-semester undergraduate research seminar. The Enron corpus is well suited to statistical analyses at all levels of undergraduate education. Through this article's focus on centrality, students can explore…

  3. 32 CFR 516.20 - Habeas Corpus.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Habeas Corpus. 516.20 Section 516.20 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY AID OF CIVIL AUTHORITIES AND PUBLIC RELATIONS LITIGATION Reporting Legal Proceedings to HQDA § 516.20 Habeas Corpus. (a) General. A soldier...

  4. Subset of early radial glial progenitors that contribute to the development of callosal neurons is absent from avian brain

    PubMed Central

    García-Moreno, Fernando; Molnár, Zoltán

    2015-01-01

    The classical view of mammalian cortical development suggests that pyramidal neurons are generated in a temporal sequence, with all radial glial cells (RGCs) contributing to both lower and upper neocortical layers. A recent opposing proposal suggests there is a subgroup of fate-restricted RGCs in the early neocortex, which generates only upper-layer neurons. Little is known about the existence of fate restriction of homologous progenitors in other vertebrate species. We investigated the lineage of selected Emx2+ [vertebrate homeobox gene related to Drosophila empty spiracles (ems)] RGCs in mouse neocortex and chick forebrain and found evidence for both sequential and fate-restricted programs only in mouse, indicating that these complementary populations coexist in the developing mammalian but not avian brain. Among a large population of sequentially programmed RGCs in the mouse brain, a subset of self-renewing progenitors lack neurogenic potential during the earliest phase of corticogenesis. After a considerable delay, these progenitors generate callosal upper-layer neurons and glia. On the other hand, we found no homologous delayed population in any sectors of the chick forebrain. This finding suggests that neurogenic delay of selected RGCs may be unique to mammals and possibly associated with the evolution of the corpus callosum. PMID:26305942

  5. Subset of early radial glial progenitors that contribute to the development of callosal neurons is absent from avian brain.

    PubMed

    García-Moreno, Fernando; Molnár, Zoltán

    2015-09-01

    The classical view of mammalian cortical development suggests that pyramidal neurons are generated in a temporal sequence, with all radial glial cells (RGCs) contributing to both lower and upper neocortical layers. A recent opposing proposal suggests there is a subgroup of fate-restricted RGCs in the early neocortex, which generates only upper-layer neurons. Little is known about the existence of fate restriction of homologous progenitors in other vertebrate species. We investigated the lineage of selected Emx2+ [vertebrate homeobox gene related to Drosophila empty spiracles (ems)] RGCs in mouse neocortex and chick forebrain and found evidence for both sequential and fate-restricted programs only in mouse, indicating that these complementary populations coexist in the developing mammalian but not avian brain. Among a large population of sequentially programmed RGCs in the mouse brain, a subset of self-renewing progenitors lack neurogenic potential during the earliest phase of corticogenesis. After a considerable delay, these progenitors generate callosal upper-layer neurons and glia. On the other hand, we found no homologous delayed population in any sectors of the chick forebrain. This finding suggests that neurogenic delay of selected RGCs may be unique to mammals and possibly associated with the evolution of the corpus callosum. PMID:26305942

  6. Medroxyprogesterone in Treating Patients With Endometrioid Adenocarcinoma of the Uterine Corpus

    ClinicalTrials.gov

    2016-03-17

    Endometrial Adenocarcinoma; Endometrial Adenosquamous Carcinoma; Endometrial Endometrioid Adenocarcinoma, Variant With Squamous Differentiation; Recurrent Uterine Corpus Carcinoma; Stage I Uterine Corpus Cancer; Stage II Uterine Corpus Cancer; Stage III Uterine Corpus Cancer; Stage IV Uterine Corpus Cancer

  7. [Medicine and astrology in Arnau's corpus].

    PubMed

    Giralt, Sebastià

    2006-01-01

    The role of astrology in Arnau de Vilanova's medical work is revisited with special attention to the problems of authorship posed by the astrological writings of Arnau's corpus and to their hypothetical chronology. PMID:17214132

  8. Minimal absent words in four human genome assemblies.

    PubMed

    Garcia, Sara P; Pinho, Armando J

    2011-01-01

    Minimal absent words have been computed in genomes of organisms from all domains of life. Here, we aim to contribute to the catalogue of human genomic variation by investigating the variation in number and content of minimal absent words within a species, using four human genome assemblies. We compare the reference human genome GRCh37 assembly, the HuRef assembly of the genome of Craig Venter, the NA12878 assembly from cell line GM12878, and the YH assembly of the genome of a Han Chinese individual. We find the variation in number and content of minimal absent words between assemblies more significant for large and very large minimal absent words, where the biases of sequencing and assembly methodologies become more pronounced. Moreover, we find generally greater similarity between the human genome assemblies sequenced with capillary-based technologies (GRCh37 and HuRef) than between the human genome assemblies sequenced with massively parallel technologies (NA12878 and YH). Finally, as expected, we find the overall variation in number and content of minimal absent words within a species to be generally smaller than the variation between species. PMID:22220210

  9. Learner-Corpus Interaction: A Locus of Microgenesis in Corpus-Assisted L2 Writing

    ERIC Educational Resources Information Center

    Park, Kwanghyun

    2012-01-01

    This paper examines the processes through which learners interact with a corpus system and microgenetic development emerges from the interaction. The corpus system described in this paper is capable of retrieving highly relevant textual examples tailored to individual needs. Data were collected from an undergraduate ESL composition course in North…

  10. 77 FR 2448 - Special Local Regulation; HITS Triathlon; Corpus Christi Bayfront, Corpus Christi, TX

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-18

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation; HITS Triathlon; Corpus Christi... from portions of the Corpus Christi Bayfront area during the HITS Triathlon on February 18th and 19th, 2012. This Special Local Regulation is necessary to ensure the safety of HITS Triathlon...

  11. 42 CFR 31.6 - Personnel absent without leave.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Personnel absent without leave. 31.6 Section 31.6 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICAL CARE AND EXAMINATIONS MEDICAL CARE FOR CERTAIN PERSONNEL OF THE COAST GUARD, NATIONAL OCEAN SURVEY, PUBLIC...

  12. Vampire Selfie: A Curious Case of an Absent Reflection

    ERIC Educational Resources Information Center

    Grossman, Joshua M.

    2014-01-01

    This article presents a puzzle for the optics section of an introductory course on reflections. A teacher could ask students to explain the phenomenon of the "vampire selfie" or the absent reflection. How could that be? What physics caused this curious phenomenon? The article explains light refraction and its effect on what we see and…

  13. Investigating Whether Contacting Absent Students Increases Course Success

    ERIC Educational Resources Information Center

    Stucky, Thomas D.

    2008-01-01

    Studies suggest that student attendance in college classes increases course success. Yet, surprisingly few studies have examined strategies to increase student attendance. The goal of the current study is to consider whether contacting consistently absent students increases success in an undergraduate research methods course. Results of this…

  14. The Production of Present and Absent Presences in Education

    ERIC Educational Resources Information Center

    Frelin, Anneli; Grannäs, Jan

    2013-01-01

    Drawing on the distinction between absent and present presences, this article contributes to our understanding of how new managerial and performative discourses are played out in a secondary school context in Sweden. The consequences of numerous educational reforms during the last 20 years include a surge of new independent schools and increased…

  15. Nepotism absent in insect societies - or is it?

    PubMed

    Wenseleers, Tom

    2007-08-01

    Inclusive fitness theory, put forward by English biologist William Hamilton in 1964, is considered by many as the most important addition to the theory of natural selection since Darwin. One prediction of the theory is that animals should often show a tendency to nepotistically favour close relatives. Goodisman et al. (2007) test this theory for the first time using molecular methods in a vespine wasp, the eastern yellowjacket, Vespula maculifrons. Somewhat surprisingly, nepotism was found to be absent. This begs the question why nepotism is predicted by theory, yet in a growing list of species is shown to be absent. Is inclusive fitness theory in trouble? As we show, it is not: costs and constraints explain the general absence of queen rearing nepotism, and nepotism in insect societies in fact is well supported in the context of male rearing and manipulation of colony sex ratios. PMID:17651186

  16. Apes Communicate about Absent and Displaced Objects: Methodology Matters

    PubMed Central

    Lyn, Heidi; Russell, Jamie L.; Leavens, David A.; Bard, Kim A.; Boysen, Sarah T.; Schaeffer, Jennifer A.; Hopkins, William D.

    2013-01-01

    Displaced reference is the ability to refer to an item that has been moved (displaced) in space and/or time, and has been called one of the true hallmarks of referential communication. Several studies suggest that nonhuman primates have this capability, but a recent experiment concluded that in a specific situation (absent entities) human infants display displaced reference but chimpanzees do not. Here we show that chimpanzees and bonobos of diverse rearing histories are capable of displaced reference to absent and displaced objects. It is likely that some of the conflicting findings from animal cognition studies are due to relatively minor methodological differences, but are compounded by interpretation errors. Comparative studies are of great importance in elucidating the evolution of human cognition, however, greater care must be taken with methodology and interpretation for these studies to accurately reflect species differences. PMID:23681052

  17. PHACE syndrome and congenitally absent thyroid gland at MR imaging.

    PubMed

    Mamlouk, Mark D; Yu, John-Paul J; Asch, Sarah; Mathes, Erin F

    2016-01-01

    PHACE syndrome is a rare neurocutaneous disorder characterized by posterior fossa malformations, hemangiomas, arterial anomalies, cardiac defects, and abnormalities of the eye. Thyroid disorders associated with PHACE syndrome have been described, although there are limited reports of this rare occurrence. We report a case of PHACE syndrome with congenital hypothyroidism in an infant, for which absent thyroid gland was diagnosed at magnetic resonance imaging. PMID:26995578

  18. Thrombocytopenia with absent radius in a boy and his uncle.

    PubMed

    Schnur, R E; Eunpu, D L; Zackai, E H

    1987-09-01

    We report a boy and his maternal uncle who have Thrombocytopenia-Absent Radius (TAR) syndrome. The mother of the propositus is normal. A maternal aunt has mild radial hypoplasia, possibly representing partial expression of the syndrome. A review of the literature shows several pedigrees in which relatives other than sibs were affected with TAR. Thus, autosomal recessive inheritance may not account for all cases and alternate modes of transmission should be considered. PMID:3314504

  19. Congenital hypogonadotropic hypogonadism: implications of absent mini-puberty.

    PubMed

    Dwyer, Andrew A; Jayasena, Channa N; Quinton, Richard

    2016-06-01

    The phenomenon known as "mini-puberty" refers to activation of the neonatal hypothalamo-pituitary axis causing serum concentrations of gonadotrophins and testosterone (T) to approach adult male levels. This early neonatal period is a key proliferative window for testicular germ cells and immature Sertoli cells. Although failure to spontaneously initiate (adolescent) puberty is the most evident consequence of a defective gonadotropin-releasing hormone (GnRH) neurosecretory network, absent mini-puberty is also likely to have a major impact on the reproductive phenotype of men with congenital hypogonadotrophic hypogonadism (CHH). Furthermore, the phase of male mini-puberty represents a key window-of-opportunity to identify congenital GnRH deficiency (either isolated CHH, or as part of combined pituitary hormone deficiency) in childhood. Among male neonates exhibiting "red flag" indicators for CHH (i.e. maldescended testes with or without cryptorchidism) a single serum sample (between 4-8 weeks of life) can pinpoint congenital GnRH deficiency far more rapidly and with much greater accuracy than dynamic tests performed in later childhood or adolescence. Potential consequences for missing absent mini-puberty in a male neonate include the lack of monitoring of pubertal progression/lack of progression, and the missed opportunity for early therapeutic intervention. This article will review our current understanding of the mechanisms and clinical consequences of mini-puberty. Furthermore, evidence for the optimal clinical management of patients with absent mini-puberty will be discussed. PMID:27213784

  20. Inflation Metaphor in the TIME Magazine Corpus

    ERIC Educational Resources Information Center

    Hu, Chunyu; Liu, Huijie

    2016-01-01

    A historical perspective on economy metaphor can shed new lights on economic thoughts. Based on the TIME Magazine Corpus (TMC), this paper investigates inflation metaphor over 83 years and compares findings against the economic data over the relatively corresponding period. The results show how inflation, an abstract concept and a normal economic…

  1. The Need for a Speech Corpus

    ERIC Educational Resources Information Center

    Campbell, Dermot F.; McDonnell, Ciaran; Meinardi, Marti; Richardson, Bunny

    2007-01-01

    This paper outlines the ongoing construction of a speech corpus for use by applied linguists and advanced EFL/ESL students. In the first part, sections 1-4, the need for improvements in the teaching of listening skills and pronunciation practice for EFL/ESL students is noted. It is argued that the use of authentic native-to-native speech is…

  2. 38 CFR 3.263 - Corpus of estate; net worth.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Corpus of estate; net....263 Corpus of estate; net worth. (a) General. The following rules are for application in determining the corpus of estate of a parent where dependency is a factor under § 3.250, and the net worth of...

  3. EFL Students' Perceptions of Corpus-Tools as Writing References

    ERIC Educational Resources Information Center

    Lai, Shu-Li

    2015-01-01

    A number of studies have suggested the potentials of corpus tools in vocabulary learning. However, there are still some concerns. Corpus tools might be too complicated to use; example sentences retrieved from corpus tools might be too difficult to understand; processing large number of sample sentences could be challenging and time-consuming;…

  4. Using a Corpus in a 300-Level Spanish Grammar Course

    ERIC Educational Resources Information Center

    Benavides, Carlos

    2015-01-01

    The present study examined the use and effectiveness of a large corpus--the Corpus del Español (Davies, 2002)--in a 300-level Spanish grammar university course. Students conducted hands-on corpus searches with the goal of finding concordances containing particular types of collocations (combinations of words that tend to co-occur) and tokens (any…

  5. Can a Graded Reader Corpus Provide "Authentic" Input?

    ERIC Educational Resources Information Center

    Allan, Rachel

    2009-01-01

    In addition to their intended purpose, graded reader texts can be made into a corpus appropriate for use with lower-level learners. Here I consider using such a corpus for data-driven learning (DDL), to make this approach more accessible to intermediate level students. However, how far does grading the corpus in this way compromise the…

  6. Concept annotation in the CRAFT corpus

    PubMed Central

    2012-01-01

    Background Manually annotated corpora are critical for the training and evaluation of automated methods to identify concepts in biomedical text. Results This paper presents the concept annotations of the Colorado Richly Annotated Full-Text (CRAFT) Corpus, a collection of 97 full-length, open-access biomedical journal articles that have been annotated both semantically and syntactically to serve as a research resource for the biomedical natural-language-processing (NLP) community. CRAFT identifies all mentions of nearly all concepts from nine prominent biomedical ontologies and terminologies: the Cell Type Ontology, the Chemical Entities of Biological Interest ontology, the NCBI Taxonomy, the Protein Ontology, the Sequence Ontology, the entries of the Entrez Gene database, and the three subontologies of the Gene Ontology. The first public release includes the annotations for 67 of the 97 articles, reserving two sets of 15 articles for future text-mining competitions (after which these too will be released). Concept annotations were created based on a single set of guidelines, which has enabled us to achieve consistently high interannotator agreement. Conclusions As the initial 67-article release contains more than 560,000 tokens (and the full set more than 790,000 tokens), our corpus is among the largest gold-standard annotated biomedical corpora. Unlike most others, the journal articles that comprise the corpus are drawn from diverse biomedical disciplines and are marked up in their entirety. Additionally, with a concept-annotation count of nearly 100,000 in the 67-article subset (and more than 140,000 in the full collection), the scale of conceptual markup is also among the largest of comparable corpora. The concept annotations of the CRAFT Corpus have the potential to significantly advance biomedical text mining by providing a high-quality gold standard for NLP systems. The corpus, annotation guidelines, and other associated resources are freely available at http

  7. Vampire Selfie: A Curious Case of an Absent Reflection

    NASA Astrophysics Data System (ADS)

    Grossman, Joshua M.

    2014-11-01

    During a recent ride in an elevator, I was startled by an observation. Once the door closed, the features on the back wall of the elevator were evident in a reflection on the door; however, my own reflection appeared absent (see Fig. 1). How could that be? What physics caused this curious phenomenon? The elevator had wooden molding, including horizontal strips that ran all the way around the back and sides (see Fig. 2). These horizontal strips were what showed up most clearly in the reflection. The door's surface was brushed metal with the brush marks all running vertically. Therein lay the solution.

  8. Absent without leave; a neuroenergetic theory of mind wandering.

    PubMed

    Killeen, Peter R

    2013-01-01

    Absent minded people are not under the control of task-relevant stimuli. According to the Neuroenergetics Theory of attention (NeT), this lack of control is often due to fatigue of the relevant processing units in the brain caused by insufficient resupply of the neuron's preferred fuel, lactate, from nearby astrocytes. A simple drift model of information processing accounts for response-time statistics in a paradigm often used to study inattention, the Sustained Attention to Response Task (SART). It is suggested that errors and slowing in this fast-paced, response-engaging task may have little to due with inattention. Slower-paced and less response-demanding tasks give greater license for inattention-aka absent-mindedness, mind-wandering. The basic NeT is therefore extended with an ancillary model of attentional drift and recapture. This Markov model, called NEMA, assumes probability λ of lapses of attention from 1 s to the next, and probability α of drifting back to the attentional state. These parameters measure the strength of attraction back to the task (α), or away to competing mental states or action patterns (λ); their proportion determines the probability of the individual being inattentive at any point in time over the long run. Their values are affected by the fatigue of the brain units they traffic between. The deployment of the model is demonstrated with a data set involving paced responding. PMID:23847559

  9. Developing a corpus of spoken language variability

    NASA Astrophysics Data System (ADS)

    Carmichael, Lesley; Wright, Richard; Wassink, Alicia Beckford

    2003-10-01

    We are developing a novel, searchable corpus as a research tool for investigating phonetic and phonological phenomena across various speech styles. Five speech styles have been well studied independently in previous work: reduced (casual), careful (hyperarticulated), citation (reading), Lombard effect (speech in noise), and ``motherese'' (child-directed speech). Few studies to date have collected a wide range of styles from a single set of speakers, and fewer yet have provided publicly available corpora. The pilot corpus includes recordings of (1) a set of speakers participating in a variety of tasks designed to elicit the five speech styles, and (2) casual peer conversations and wordlists to illustrate regional vowels. The data include high-quality recordings and time-aligned transcriptions linked to text files that can be queried. Initial measures drawn from the database provide comparison across speech styles along the following acoustic dimensions: MLU (changes in unit duration); relative intra-speaker intensity changes (mean and dynamic range); and intra-speaker pitch values (minimum, maximum, mean, range). The corpus design will allow for a variety of analyses requiring control of demographic and style factors, including hyperarticulation variety, disfluencies, intonation, discourse analysis, and detailed spectral measures.

  10. Transvection at the Eyes Absent Gene of Drosophila

    PubMed Central

    Leiserson, W. M.; Bonini, N. M.; Benzer, S.

    1994-01-01

    The Drosophila eyes absent (eya) gene is required for survival and differentiation of eye progenitor cells. Loss of gene function in the eye results in reduction or absence of the adult compound eye. Certain combinations of eya alleles undergo partial complementation, with dramatic restoration of eye size. This interaction is sensitive to the relative positions of the two alleles in the genome; rearrangements predicted to disrupt pairing of chromosomal homologs in the eya region disrupt complementation. Ten X-ray-induced rearrangements that suppress the interaction obey the same general rules as those tha disrupt transvection at the bithorax complex and the decapentaplegic gene. Moreover, like transvection in those cases, the interaction at eya depends on the presence of normal zeste function. The discovery of transvection at eya suggests that transvection interactions of this type may be more prevalent than generally thought. PMID:7896099

  11. Tetralogy of Fallot with absent pulmonary valve. A continuing challenge.

    PubMed

    Jekel, L; Benatar, A; Bennink, G B; Woolley, S R; van de Wal, H J

    1998-01-01

    Absent pulmonary valve syndrome (APVS); the combination of tetralogy of Fallot (TOF) with agenesis of the pulmonary valve, is a relatively rare cardiac malformation. Despite the anatomic similarity with classic TOF, the pathophysiology is strikingly different. Data on 10 patients (3 male, 7 female) with APVS, treated between January 1978 and December 1995, were retrospectively reviewed. During this period a total of 2920 children underwent correction of a variety of congenital cardiac anomalies, of which 246 patients (8%) had a correction for TOF. Two patients with APVS presented within the first four months of life with severe cardiorespiratory distress and required several operative procedures. The remaining eight patients had only mild to moderate respiratory and/or cardiac symptoms and elective intracardiac repair was performed on those between the ages of 10 months and 9.5 years. Associated cardiac anomalies seen in five patients included aberrant coronary artery, absent or interrupted left pulmonary artery, partial AVSD and aberrant azygos continuation. In those electively corrected, the strategies used were ventriculotomy (7), pulmonary homograft (3) and aneurysmorrhaphy (2). There were two deaths, one in each group of patients, as a result of progressive respiratory insufficiency and cardiac tamponade, respectively. The follow-up of the eight survivors ranged from 2 to 11 years (median 6.75). All have a normal effort tolerance; only one child is on digoxin therapy, and one child continues to suffer bronchospastis episodes. Our experience with infants with this lesion is limited but underlines the different approaches required, depending on the age of presentation. PMID:9802139

  12. Creation of a new longitudinal corpus of clinical narratives.

    PubMed

    Kumar, Vishesh; Stubbs, Amber; Shaw, Stanley; Uzuner, Özlem

    2015-12-01

    The 2014 i2b2/UTHealth Natural Language Processing (NLP) shared task featured a new longitudinal corpus of 1304 records representing 296 diabetic patients. The corpus contains three cohorts: patients who have a diagnosis of coronary artery disease (CAD) in their first record, and continue to have it in subsequent records; patients who do not have a diagnosis of CAD in the first record, but develop it by the last record; patients who do not have a diagnosis of CAD in any record. This paper details the process used to select records for this corpus and provides an overview of novel research uses for this corpus. This corpus is the only annotated corpus of longitudinal clinical narratives currently available for research to the general research community. PMID:26433122

  13. The Hebrew CHILDES corpus: transcription and morphological analysis

    PubMed Central

    Albert, Aviad; MacWhinney, Brian; Nir, Bracha

    2014-01-01

    We present a corpus of transcribed spoken Hebrew that reflects spoken interactions between children and adults. The corpus is an integral part of the CHILDES database, which distributes similar corpora for over 25 languages. We introduce a dedicated transcription scheme for the spoken Hebrew data that is sensitive to both the phonology and the standard orthography of the language. We also introduce a morphological analyzer that was specifically developed for this corpus. The analyzer adequately covers the entire corpus, producing detailed correct analyses for all tokens. Evaluation on a new corpus reveals high coverage as well. Finally, we describe a morphological disambiguation module that selects the correct analysis of each token in context. The result is a high-quality morphologically-annotated CHILDES corpus of Hebrew, along with a set of tools that can be applied to new corpora. PMID:25419199

  14. Corpus Christi, Nueces, and Aransas Bays

    USGS Publications Warehouse

    Handley, Lawrence R.; Spear, Kathryn A.; Eleonor Taylor; Thatcher, Cindy

    2015-01-01

    Corpus Christi Bay and Nueces Bay comprise the middle estuarine portion of Texas’ Coastal Bend region (Figure 1; Burgan and Engle, 2006). Aransas Bay is part of the upper estuarine portion of the region. These bays make up part of the Coastal Bend Bays and Estuaries Program, one of the many estuarine areas in the U.S. Environmental Protection Agency’s National Estuary Program (Holt, 1998). The Coastal Bend region is sub-humid and sub-tropical. Summers are long, hot, and humid, and winters are short and mild. The landscape around the estuaries is dominated by row crops, pastures, and brushy rangeland (Handley and others, 2007). The Nueces River, along with other smaller rivers and creeks, provides freshwater inflow—along with essential nutrients and sediment— into Nueces Bay, which feeds into Corpus Christi Bay (Holt, 1998). Freshwater inflow into the Aransas Bay comes from Mission River, Aransas River, and Copano Creek. The region is relatively dry otherwise and prone to droughts. Corpus Christi receives an average of 76.2 cm (30 in) of rain annually; evaporation usually exceeds 177.8 cm (70 in) (Holt, 1998; Handley and others, 2007). The San Antonio-Nueces Coastal Basin drains into Aransas Bay. The Nueces River basin covers 43,253 km2 (16,700 miles2 ), from northwest of San Antonio, flowing southeast to where it drains into Nueces and Corpus Christi Bays (Holt, 1998). The Nueces-Rio Grande basin covers approximately 18,648 1 U.S. Geological Survey National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506 2 Harte Research Institute for Gulf of Mexico Studies, Texas A&M University - Corpus Christi, 6300 Ocean Drive, Unit 5869, Corpus Christi, Texas 78412 2 km2 (7,200 miles2 ) and flows partially into Corpus Christi Bay (as well as the upper Laguna Madre). The inflow from Nueces River has declined by approximately 20 percent over the past several decades, partly due to construction of lakes and reservoirs, particularly Lake Corpus Christi

  15. Beyond re-membering: phantom sensations of congenitally absent limbs.

    PubMed

    Brugger, P; Kollias, S S; Müri, R M; Crelier, G; Hepp-Reymond, M C; Regard, M

    2000-05-23

    Phantom limbs are traditionally conceptualized as the phenomenal persistence of a body part after deafferentation. Previous clinical observations of subjects with phantoms of congenitally absent limbs are not compatible with this view, but, in the absence of experimental work, the neural basis of such "aplasic phantoms" has remained enigmatic. In this paper, we report a series of behavioral, imaging, and neurophysiological experiments with a university-educated woman born without forearms and legs, who experiences vivid phantom sensations of all four limbs. Visuokinesthetic integration of tachistoscopically presented drawings of hands and feet indicated an intact somatic representation of these body parts. Functional magnetic resonance imaging of phantom hand movements showed no activation of primary sensorimotor areas, but of premotor and parietal cortex bilaterally. Movements of the existing upper arms produced activation expanding into the hand territories deprived of afferences and efferences. Transcranial magnetic stimulation of the sensorimotor cortex consistently elicited phantom sensations in the contralateral fingers and hand. In addition, premotor and parietal stimulation evoked similar phantom sensations, albeit in the absence of motor evoked potentials in the stump. These data indicate that body parts that have never been physically developed can be represented in sensory and motor cortical areas. Both genetic and epigenetic factors, such as the habitual observation of other people moving their limbs, may contribute to the conscious experience of aplasic phantoms. PMID:10801982

  16. The Eyes Absent proteins in development and disease.

    PubMed

    Tadjuidje, Emmanuel; Hegde, Rashmi S

    2013-06-01

    The Eyes Absent (EYA) proteins, first described in the context of fly eye development, are now implicated in processes as disparate as organ development, innate immunity, DNA damage repair, photoperiodism, angiogenesis, and cancer metastasis. These functions are associated with an unusual combination of biochemical activities: tyrosine phosphatase and threonine phosphatase activities in separate domains, and transactivation potential when associated with a DNA-binding partner. EYA mutations are linked to multiorgan developmental disorders, as well as to adult diseases ranging from dilated cardiomyopathy to late-onset sensorineural hearing loss. With the growing understanding of EYA biochemical and cellular activity, biological function, and association with disease, comes the possibility that the EYA proteins are amenable to the design of targeted therapeutics. The availability of structural information, direct links to disease states, available animal models, and the fact that they utilize unconventional reaction mechanisms that could allow specificity, suggest that EYAs are well-positioned for drug discovery efforts. This review provides a summary of EYA structure, activity, and function, as they relate to development and disease, with particular emphasis on recent findings. PMID:22971774

  17. Distinct Biochemical Activities of Eyes absent During Drosophila Eye Development

    PubMed Central

    Jin, Meng; Mardon, Graeme

    2016-01-01

    Eyes absent (Eya) is a highly conserved transcriptional coactivator and protein phosphatase that plays vital roles in multiple developmental processes from Drosophila to humans. Eya proteins contain a PST (Proline-Serine-Threonine)-rich transactivation domain, a threonine phosphatase motif (TPM), and a tyrosine protein phosphatase domain. Using a genomic rescue system, we find that the PST domain is essential for Eya activity and Dac expression, and the TPM is required for full Eya function. We also find that the threonine phosphatase activity plays only a minor role during Drosophila eye development and the primary function of the PST and TPM domains is transactivation that can be largely substituted by the heterologous activation domain VP16. Along with our previous results that the tyrosine phosphatase activity of Eya is dispensable for normal Eya function in eye formation, we demonstrate that a primary function of Eya during Drosophila eye development is as a transcriptional coactivator. Moreover, the PST/TPM and the threonine phosphatase activity are not required for in vitro interaction between retinal determination factors. Finally, this work is the first report of an Eya-Ey physical interaction. These findings are particularly important because they highlight the need for an in vivo approach that accurately dissects protein function. PMID:26980695

  18. Distinct Biochemical Activities of Eyes absent During Drosophila Eye Development.

    PubMed

    Jin, Meng; Mardon, Graeme

    2016-01-01

    Eyes absent (Eya) is a highly conserved transcriptional coactivator and protein phosphatase that plays vital roles in multiple developmental processes from Drosophila to humans. Eya proteins contain a PST (Proline-Serine-Threonine)-rich transactivation domain, a threonine phosphatase motif (TPM), and a tyrosine protein phosphatase domain. Using a genomic rescue system, we find that the PST domain is essential for Eya activity and Dac expression, and the TPM is required for full Eya function. We also find that the threonine phosphatase activity plays only a minor role during Drosophila eye development and the primary function of the PST and TPM domains is transactivation that can be largely substituted by the heterologous activation domain VP16. Along with our previous results that the tyrosine phosphatase activity of Eya is dispensable for normal Eya function in eye formation, we demonstrate that a primary function of Eya during Drosophila eye development is as a transcriptional coactivator. Moreover, the PST/TPM and the threonine phosphatase activity are not required for in vitro interaction between retinal determination factors. Finally, this work is the first report of an Eya-Ey physical interaction. These findings are particularly important because they highlight the need for an in vivo approach that accurately dissects protein function. PMID:26980695

  19. Selective gene expression by rat gastric corpus epithelium

    PubMed Central

    Goebel, M.; Stengel, A.; Sachs, G.

    2011-01-01

    The gastrointestinal (GI) tract is divided into several segments that have distinct functional properties, largely absorptive. The gastric corpus is the only segment thought of as largely secretory. Microarray hybridization of the gastric corpus mucosal epithelial cells was used to compare gene expression with other segments of the columnar GI tract followed by statistical data subtraction to identify genes selectively expressed by the rat gastric corpus mucosa. This provides a means of identifying less obvious specific functions of the corpus in addition to its secretion-related genes. For example, important properties found by this GI tract comparative transcriptome reflect the energy demand of acid secretion, a role in lipid metabolism, the large variety of resident neuroendocrine cells, responses to damaging agents and transcription factors defining differentiation of its epithelium. In terms of overlap of gastric corpus genes with the rest of the GI tract, the distal small bowel appears to express many of the gastric corpus genes in contrast to proximal small and large bowel. This differential map of gene expression by the gastric corpus epithelium will allow a more detailed description of major properties of the gastric corpus and may lead to the discovery of gastric corpus cell differentiation genes and those mis-regulated in gastric carcinomas. PMID:21177383

  20. Corpus Callosum Function in Verbal Dichotic Listening: Inferences from a Longitudinal Follow-Up of Relapsing-Remitting Multiple Sclerosis Patients

    ERIC Educational Resources Information Center

    Gadea, Marien; Marti-Bonmati, Luis; Arana, Estanislao; Espert, Raul; Salvador, Alicia; Casanova, Bonaventura

    2009-01-01

    This study conducted a follow-up of 13 early-onset slightly disabled Relapsing-Remitting Multiple Sclerosis (RRMS) patients within an year, evaluating both CC area measurements in a midsagittal Magnetic Resonance (MR) image, and Dichotic Listening (DL) testing with stop consonant vowel (C-V) syllables. Patients showed a significant progressive…

  1. Turbulent Sediment Suspension and Induced Ripple Dynamics Absent Mean Shear

    NASA Astrophysics Data System (ADS)

    Johnson, B. A.; Cowen, E.

    2014-12-01

    The uprush and backwash phases in the swash zone, the region of the beach that is alternately covered and uncovered by wave run-up, are fundamentally different events. Backwash is dominated by a growing boundary layer where the turbulence is set by the bed shear stress. In this phase traditional boundary layer turbulence models and Shields-type critical stress pickup functions work well. However, the uprush phase, while often viewed in the context of traditional boundary layer turbulence models, has little in common with the backwash phase. During uprush, the entire water column is turbulent, as it rapidly advects well-stirred highly turbulent flow generated offshore from breaking waves or collapsing bores. Turbulence levels in the uprush are several times higher than turbulent boundary layer theory would predict and hence the use of a boundary layer model to predict turbulence levels during uprush grossly under predicts the turbulence and subsequent sediment suspension in the swash zone. To study the importance of this advected turbulence to sediment suspension we conduct experiments in a water tank designed to generate horizontally homogeneous isotropic turbulence absent mean shear using randomly actuated synthetic jet arrays suspended above both a solid glass plate and a narrowly graded sediment bed. Using jet arrays with different jet spacings allows the generation of high Reynolds number turbulence with variable integral length scales, which we hypothesize control the characteristic length scales in the induced ripple field. Particle image velocimetry and acoustic Doppler velocimetry measurements are used to characterize the near-bed flow and this unique turbulent boundary layer. Metrics include the mean flow and turbulence intensities and stresses, temporal and spatial spectra, dissipation of turbulent kinetic energy, and integral length scales of the turbulence. We leverage our unique dataset to compare the flows over impermeable fixed and permeable mobile

  2. Corpus-Based Learning of Cantonese for Mandarin Speakers

    ERIC Educational Resources Information Center

    Lee, John; Wong, Tak-Sum

    2014-01-01

    This paper reports our experience in using a parallel corpus to teach Cantonese, a variety of Chinese spoken in Hong Kong, as a second language. The parallel corpus consists of pairs of word-aligned sentences in Cantonese and Mandarin Chinese, drawn from television programs in Hong Kong (Lee, 2011). We evaluated our pedagogical approach with…

  3. Use of "Google Scholar" in Corpus-Driven EAP Research

    ERIC Educational Resources Information Center

    Brezina, Vaclav

    2012-01-01

    This primarily methodological article makes a proposition for linguistic exploration of textual resources available through the "Google Scholar" search engine. These resources ("Google Scholar virtual corpus") are significantly larger than any existing corpus of academic writing. "Google Scholar", however, was not designed for linguistic searches…

  4. Corpus-Supported Academic Writing: How Can Technology Help?

    ERIC Educational Resources Information Center

    Chitez, Madalina; Rapp, Christian; Kruse, Otto

    2015-01-01

    Phraseology has long been used in L2 teaching of academic writing, and corpus linguistics has played a major role in the compilation and assessment of academic phrases. However, there are only a few interactive academic writing tools in which corpus methodology is implemented in a real-time design to support formulation processes. In this paper,…

  5. Developing Corpus-Based Materials to Teach Pragmatic Routines

    ERIC Educational Resources Information Center

    Bardovi-Harlig, Kathleen; Mossman, Sabrina; Vellenga, Heidi E.

    2015-01-01

    This article describes how to develop teaching materials for pragmatics based on authentic language by using a spoken corpus. The authors show how to use the corpus in conjunction with textbooks to identify pragmatic routines for speech acts and how to extract appropriate language samples and adapt them for classroom use. They demonstrate how to…

  6. CORPUS LUTEUM: ANIMAL MODELS OF POSSIBLE RELEVANCE TO REPRODUCTIVE TOXICOLOGY

    EPA Science Inventory

    The presence of a normally functioning corpus luteum is an essential requirement for the maintenance of gestation in mammals. he chief function of the corpus luteum in all species is to synthesize the steroid hormone progesterone that is necessary for implantation and for the sub...

  7. Cadec: A corpus of adverse drug event annotations.

    PubMed

    Karimi, Sarvnaz; Metke-Jimenez, Alejandro; Kemp, Madonna; Wang, Chen

    2015-06-01

    CSIRO Adverse Drug Event Corpus (Cadec) is a new rich annotated corpus of medical forum posts on patient-reported Adverse Drug Events (ADEs). The corpus is sourced from posts on social media, and contains text that is largely written in colloquial language and often deviates from formal English grammar and punctuation rules. Annotations contain mentions of concepts such as drugs, adverse effects, symptoms, and diseases linked to their corresponding concepts in controlled vocabularies, i.e., SNOMED Clinical Terms and MedDRA. The quality of the annotations is ensured by annotation guidelines, multi-stage annotations, measuring inter-annotator agreement, and final review of the annotations by a clinical terminologist. This corpus is useful for studies in the area of information extraction, or more generally text mining, from social media to detect possible adverse drug reactions from direct patient reports. The corpus is publicly available at https://data.csiro.au.(1). PMID:25817970

  8. Insights from a Learner Corpus as Opposed to a Native Corpus about Cohesive Devices in an Academic Writing Context

    ERIC Educational Resources Information Center

    Ersanli, Ceylan Yangin

    2015-01-01

    This study reports on the insights from an EFL learner corpora (a total of 151 essays and 49,690 words) generated from essays collected over the years in a Turkish state university from freshmen students enrolling in the Advanced Writing course. The comparison of cohesive devices in the non-native corpus (NNC) with those in a native corpus (NC)…

  9. 77 FR 34034 - Corpus Christi Liquefaction, LLC; Cheniere Corpus Christi Pipeline, L.P.; Notice of Intent To...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-08

    ....; Notice of Intent To Prepare an Environmental Assessment for the Planned Corpus Christi LNG Terminal and... assessment (EA) that will discuss the environmental impacts of the planned Corpus Christi LNG Terminal and... (LNG) export and import terminal, and a natural gas transmission pipeline in Nueces and San...

  10. EEAP lighting survey study at the Corpus Christi Army Depot, Corpus Christi, Texas. Final report

    SciTech Connect

    1995-04-05

    This energy conservation study was performed by Huitt-Zollars Inc, for the U.S. Army Engineer District (USAED), Fort Worth, under contract number DACAC63-94-D-0015. The study was conducted at Corpus Christi Army Depot (CCAD) in Corpus Christi, Texas, between October 3, 1994 and April 5, 1995. The site survey and data collection was performed by C.A. Pieper, P.E. and Tom Luckett, Lighting Designer. The purpose of the study was to perform a limited site survey of specific buildings at the facility, identify specific Energy Conservation Opportunities (ECOs) that exist, and then evaluate these ECOs for technical and economic feasibility. These ECOs were limited to building interior lighting and it`s effects on the heating, ventilating and air conditioning.

  11. EEAP-lighting survey study at the Corpus Christi Army Depot Corpus Christi, Texas. Final report

    SciTech Connect

    1995-04-05

    This energy conservation study was performed by Huitt-Zollars Inc, for the U.S. Army Engineer District (USAED), Fort Worth, under contract number DACAC63-94-D-00l5. The study was conducted at Corpus Christi Army Depot (CCAD) in Corpus Christi, Texas, between October 3, 1994 and April 5, 1995. The site survey and data collection was performed by C.A. Pieper, P.E. and Tom Luckett, Lighting Designer. The purpose of the study was to perform a limited site survey of specific buildings at the facility, identify specific Energy Conservation Opportunities (ECOs) that exist, and then evaluate these ECOs for technical and economic feasibility. These ECOs were limited to building interior lighting and its effects on the heating, ventilating and air conditioning (HVAC) systems.

  12. Cytokines and Angiogenesis in the Corpus Luteum

    PubMed Central

    Galvão, António M.; Ferreira-Dias, Graça; Skarzynski, Dariusz J.

    2013-01-01

    In adults, physiological angiogenesis is a rare event, with few exceptions as the vasculogenesis needed for tissue growth and function in female reproductive organs. Particularly in the corpus luteum (CL), regulation of angiogenic process seems to be tightly controlled by opposite actions resultant from the balance between pro- and antiangiogenic factors. It is the extremely rapid sequence of events that determines the dramatic changes on vascular and nonvascular structures, qualifying the CL as a great model for angiogenesis studies. Using the mare CL as a model, reports on locally produced cytokines, such as tumor necrosis factor α (TNF), interferon gamma (IFNG), or Fas ligand (FASL), pointed out their role on angiogenic activity modulation throughout the luteal phase. Thus, the main purpose of this review is to highlight the interaction between immune, endothelial, and luteal steroidogenic cells, regarding vascular dynamics/changes during establishment and regression of the equine CL. PMID:23840095

  13. Presence of sensory nerve corpuscles in the human corpus and cervix uteri during pregnancy and labor as revealed by immunohistochemistry

    PubMed Central

    Tingaker, Berith K; Ekman-Ordeberg, Gunvor; Forsgren, Sture

    2006-01-01

    Background The uterus is exposed to changes such as enlargement and distension during pregnancy and labor. In these processes and in the process of cervical ripening, proprioceptive information is likely to be of great importance. Therefore, we wanted to study the possible existence of sensory nerve corpuscles in uterine corpus and cervix during pregnancy and labor. Studies on this aspect have not previously been perfomed. Methods Biopsies were taken from the upper edge of the hysterotomy during caesarean section at term (n = 8), in labor (n = 5) and from the corresponding area in the non-pregnant uterus after hysterectomy (n = 7). Cervical biopsies were obtained transvaginally from the anterior cervical lip. Serial cryostat sections were prepared for immunohistochemistry using polyclonal antibodies against nerve growth factor receptor p75, protein gene product 9.5 and S-100. Results Structures with the characteristics of sensory nerve corpuscles were observed in several specimens after staining for p75, PGP 9.5 and S-100. They were observed in specimens of the non-pregnant corpus and cervix and also in specimens of the pregnant cervix before onset of labor. However, they were absent in all specimens during labor. Conclusion Sensory corpuscles have here for the first time been detected in the human corpus and cervix uteri. Studies on the importance of the corpuscles in relation to the protective reflex actions that occur in the uterus during pregnancy should be performed in the future. PMID:16938139

  14. Severe form of radiculo - myelo - neuropathy with meningo - encephalitis secondary to Angiostrongylus cantonensis infection: unusual corpus callosal lesions and serial magnetic resonance imaging findings.

    PubMed

    Nalini, Atchayaram; Ramakrishna, Anil; Dekumoy, Paron; Kumar, Raju Ravi; Pakdee, Wallop; Saini, Jitender; Hegde, Vinay S

    2013-01-01

    A 43-year-old man presented with the symptoms of recurrent lower abdominal pain, malaise and loss of appetite of 3-week duration, followed by acute onset of generalized paresthesias, fever and headache which progressed over few days to quadriparesis, altered sensorium, urinary and fecal incontinence. He had consumed raw tongue, liver, gall bladder and testicles of monitor lizard (Varanus bengalensis). Blood picture showed eosinophilia and cerebrospinal fluid (CSF) analysis revealed elevated protein and eosinophilia. Serum and CSF serology was positive for angiostrongyliasis. Magnetic resonance imaging showed focal hyperintense lesions in the corpus callosum and brainstem and an enhancing lesion in the cerebellum. Post-contrast T1-weighted axial images of spine showed evidence of cervical cord hyperintense lesions and root enhancement. Susceptibility weighted images/phase images showed unusual feature of multiple hemorrhagic lesions in the posterior fossa and supratentorial areas. Diffusion showed no restriction of corpus callosal lesions. Patient was treated with the high dose parenteral steroids with albendazole and at 6-month follow-up and had a remarkable recovery. PMID:24005735

  15. Corpus Linguistics and the Design of a Response Message

    NASA Astrophysics Data System (ADS)

    Atwell, E.

    2002-01-01

    Most research related to SETI, the Search for Extra-Terrestrial Intelligence, is focussed on techniques for detection of possible incoming signals from extra-terrestrial intelligent sources (e.g. Turnbull et al. 1999), and algorithms for analysis of these signals to identify intelligent language-like characteristics (e.g. Elliott and Atwell 1999, 2000). However, another issue for research and debate is the nature of our response, should a signal arrive and be detected. The design of potentially the most significant communicative act in history should not be decided solely by astrophysicists; the Corpus Linguistics research community has a contribution to make to what is essentially a Corpus design and implementation project. (Vakoch 1998) advocated that the message constructed to transmit to extraterrestrials should include a broad, representative collection of perspectives rather than a single viewpoint or genre; this should strike a chord with Corpus Linguists for whom a central principle is that a corpus must be "balanced" to be representative (Meyer 2001). One idea favoured by SETI researchers is to transmit an encyclopaedia summarising human knowledge, such as the Encyclopaedia Britannica, to give ET communicators an overview and "training set" key to analysis of subsequent messages. Furthermore, this should be sent in several versions in parallel: the text; page-images, to include illustrations left out of the text-file and perhaps some sort of abstract linguistic representation of the text, using a functional or logic language (Ollongren 1999, Freudenthal 1960). The idea of "enriching" the message corpus with annotations at several levels should also strike a chord with Corpus Linguists who have long known that Natural language exhibits highly complex multi-layering sequencing, structural and functional patterns, as difficult to model as sequences and structures found in more traditional physical and biological sciences. Some corpora have been annotated with

  16. The tolerance of feline corpus and cauda spermatozoa to cryostress.

    PubMed

    Kunkitti, Panisara; Bergqvist, Ann-Sofi; Sjunnesson, Ylva; Johannisson, Anders; Axnér, Eva

    2016-02-01

    Epididymal sperm preservation can be used to avoid the total loss of genetic material in threatened species. Spermatozoa from the corpus, as from the cauda, are motile and can undergo capacitation. Thus, they can potentially be preserved for assisted reproductive technologies. However, cryopreservation of spermatozoa has a direct detrimental effect on sperm quality. The aim of this study was to compare the chromatin stability and the survival rate of spermatozoa from the corpus and cauda epididymis after cryopreservation. Epididymal spermatozoa were collected and cryopreserved from the corpus and cauda of 12 domestic cats. Sperm motility, progressive motility, membrane integrity, acrosome integrity, and DNA integrity were evaluated before and after freezing thawing. The average total number of spermatozoa collected from the corpus was lower (10.2 × 10(6) ± 7.4) than that from the cauda epididymis (24.9 × 10(6) ± 14.4; P = 0.005). The percentage of spermatozoa with intact DNA did not differ significantly whether it was collected from the corpus or cauda regions and did not decrease after freezing thawing in either region. However, motility of spermatozoa from both regions was affected by the freezing thawing process with a significant decline in motility after thaw compared with fresh spermatozoa. A significant difference in the percentage of motile sperm between the corpus and cauda was observed after the freezing thawing process (P < 0.001). Although sperm motility was lower in postthaw spermatozoa from the corpus epididymidis than from the cauda, the rate of the reduction did not differ between regions. This study indicates that the cryopreservation process does not have a negative effect on chromatin stability of feline epididymal spermatozoa. Spermatozoa from the corpus region have a similar freezability as spermatozoa from the cauda region. Therefore, preservation of spermatozoa from the corpus and the cauda epididymidis might be of value in preserving

  17. Paediatric Virology in the Hippocratic Corpus

    PubMed Central

    Mammas, Ioannis N.; Spandidos, Demetrios A.

    2016-01-01

    Hippocrates (Island of Kos, 460 B.C.-Larissa, 370 B.C.) is the founder of the most famous Medical School of the classical antiquity. In acknowledgement of his pioneering contribution to the new scientific field of Paediatric Virology, this article provides a systematic analysis of the Hippocratic Corpus, with particular focus on viral infections predominating in neonates and children. A mumps epidemic, affecting the island of Thasos in the 5th century B.C., is described in detail. ‘Herpes’, a medical term derived from the ancient Greek word ‘ἕρπειν’, meaning ‘to creep’ or ‘crawl’, is used to describe the spreading of cutaneous lesions in both childhood and adulthood. Cases of children with exanthema ‘resembling mosquito bites’ are presented in reference to varicella or smallpox infection. A variety of upper and lower respiratory tract viral infections are described with impressive accuracy, including rhinitis, pharyngitis, tonsillitis, laryngitis, bronchiolitis and bronchitis. The ‘cough of Perinthos’ epidemic, an influenza-like outbreak in the 5th century B.C., is also recorded and several cases complicated with pneumonia or fatal outcomes are discussed. Hippocrates, moreover, describes conjunctivitis, otitis, lymphadenitis, meningoencephalitis, febrile convulsions, gastroenteritis, hepatitis, poliomyelitis and skin warts, along with proposed treatment directions. Almost 2,400 years later, Hippocrates' systematic approach and methodical innovations can inspire paediatric trainees and future Paediatric Virology subspecialists. PMID:27446241

  18. Subluxation and semantics: a corpus linguistics study

    PubMed Central

    Budgell, Brian

    2016-01-01

    Introduction: The purpose of this study was to analyze the curriculum of one chiropractic college in order to discover if there were any implicit consensus definitions of the term subluxation. Methods: Using the software WordSmith Tools, the corpus of an undergraduate chiropractic curriculum was analyzed by reviewing collocated terms and through discourse analysis of text blocks containing words based on the root ‘sublux.’ Results: It was possible to identify 3 distinct concepts which were each referred to as ‘subluxation:’ i) an acute or instantaneous injurious event; ii) a clinical syndrome which manifested post-injury; iii) a physical lesion, i.e. an anatomical or physiological derangement which in most instances acted as a pain generator. Conclusions: In fact, coherent implicit definitions of subluxation exist and may enjoy broad but subconscious acceptance. However, confusion likely arises from failure to distinguish which concept an author or speaker is referring to when they employ the term subluxation. PMID:27385839

  19. Brain potentials related to corpus cavernosum electromyography.

    PubMed

    Ponseti, J; Bosinski, H A

    2010-01-01

    The aim of this study was to elucidate the relation between electrical activity in the corpus cavernosum (CC), penile responses and brain processes. EEG potentials, penile circumference and electrical activity of the CC (CC-EMG) were recorded simultaneously while male subjects were exposed to visual sexual stimuli. The trials were sorted by the penile response of the subjects (erection, maintenance or detumescence). The corresponding EEG recordings were subjected to independent component analysis (ICA) and then correlated with CC activity. We found that CC activity was decreased in the case of erection. EEG activity was found to be correlated with CC activity in most cases at the same instant or with subsequent CC activity. EEG activity at early time points after stimulus onset (<300 ms) was found to be correlated with CC activity, indicating penile response preparation at a pre-attentive processing level. These data indicate that (i) CC activity is under the control of brain processing and (ii) autonomous input reaches the CC in fractions of a second after sexual stimulus onset. Our experimental paradigm should be used for the study of psychogenic erectile dysfunctions and could help in the development of an objective measurement of this disturbance. PMID:20336074

  20. The Corpus of English as Lingua Franca in Academic Settings.

    ERIC Educational Resources Information Center

    Mauranen, Anna

    2003-01-01

    Describes a project to make a corpus of English spoken as a lingua franca in university settings in Finland. This corpus is one of the first to address the need for corpora that show the target for English-as-a-Foreign-Language learners whose goal is not to speak with native speakers but to interact in communities where English is a lingua franca.…

  1. A Corpus Investigation of Syntactic Embedding in Pirahã

    PubMed Central

    Futrell, Richard; Stearns, Laura; Everett, Daniel L.

    2016-01-01

    The Pirahã language has been at the center of recent debates in linguistics, in large part because it is claimed not to exhibit recursion, a purported universal of human language. Here, we present an analysis of a novel corpus of natural Pirahã speech that was originally collected by Dan Everett and Steve Sheldon. We make the corpus freely available for further research. In the corpus, Pirahã sentences have been shallowly parsed and given morpheme-aligned English translations. We use the corpus to investigate the formal complexity of Pirahã syntax by searching for evidence of syntactic embedding. In particular, we search for sentences which could be analyzed as containing center-embedding, sentential complements, adverbials, complementizers, embedded possessors, conjunction or disjunction. We do not find unambiguous evidence for recursive embedding of sentences or noun phrases in the corpus. We find that the corpus is plausibly consistent with an analysis of Pirahã as a regular language, although this is not the only plausible analysis. PMID:26934636

  2. A Corpus Investigation of Syntactic Embedding in Pirahã.

    PubMed

    Futrell, Richard; Stearns, Laura; Everett, Daniel L; Piantadosi, Steven T; Gibson, Edward

    2016-01-01

    The Pirahã language has been at the center of recent debates in linguistics, in large part because it is claimed not to exhibit recursion, a purported universal of human language. Here, we present an analysis of a novel corpus of natural Pirahã speech that was originally collected by Dan Everett and Steve Sheldon. We make the corpus freely available for further research. In the corpus, Pirahã sentences have been shallowly parsed and given morpheme-aligned English translations. We use the corpus to investigate the formal complexity of Pirahã syntax by searching for evidence of syntactic embedding. In particular, we search for sentences which could be analyzed as containing center-embedding, sentential complements, adverbials, complementizers, embedded possessors, conjunction or disjunction. We do not find unambiguous evidence for recursive embedding of sentences or noun phrases in the corpus. We find that the corpus is plausibly consistent with an analysis of Pirahã as a regular language, although this is not the only plausible analysis. PMID:26934636

  3. Successful Black Men from Absent-Father Homes and Their Resilient Single Mothers: A Phenomenological Study

    ERIC Educational Resources Information Center

    Wilson, Angie D.; Henriksen, Richard C.; Bustamante, Rebecca; Irby, Beverly

    2016-01-01

    The phenomenon of absent fathers is a common occurrence in today's homes that appears to be escalating, especially in Black households across the United States. The purpose of this study was to describe the lived experiences of successful Black men who were raised in absent-father homes as well as the lived experiences of their resilient single…

  4. Causal Attributions as Predictors of Academic Achievement in Father-Absent Children.

    ERIC Educational Resources Information Center

    Salzman, Stephanie A.

    The purpose of this study was to examine the potential impact of maternal attributions and self-attributions on the academic achievement of father-absent children in comparison to commonly identified family interaction and demographic variables. Subjects included 33 male and 34 female father-absent sixth graders (mean age of 11.6 years) and their…

  5. 42 CFR 410.175 - Alien absent from the United States.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 2 2013-10-01 2013-10-01 false Alien absent from the United States. 410.175... Alien absent from the United States. (a) Medicare does not pay Part B benefits for services furnished to... during the first full calendar month the alien is back in the United States....

  6. 42 CFR 410.175 - Alien absent from the United States.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Alien absent from the United States. 410.175... Alien absent from the United States. (a) Medicare does not pay Part B benefits for services furnished to... during the first full calendar month the alien is back in the United States....

  7. 42 CFR 410.175 - Alien absent from the United States.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 2 2011-10-01 2011-10-01 false Alien absent from the United States. 410.175... Alien absent from the United States. (a) Medicare does not pay Part B benefits for services furnished to... during the first full calendar month the alien is back in the United States....

  8. 42 CFR 410.175 - Alien absent from the United States.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 2 2012-10-01 2012-10-01 false Alien absent from the United States. 410.175... Alien absent from the United States. (a) Medicare does not pay Part B benefits for services furnished to... during the first full calendar month the alien is back in the United States....

  9. 42 CFR 410.175 - Alien absent from the United States.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 2 2014-10-01 2014-10-01 false Alien absent from the United States. 410.175... Alien absent from the United States. (a) Medicare does not pay Part B benefits for services furnished to... during the first full calendar month the alien is back in the United States....

  10. Disneyland Dads, Disneyland Moms? How Nonresident Parents Spend Time with Absent Children.

    ERIC Educational Resources Information Center

    Stewart, Susan D.

    1999-01-01

    Examines gender differences in how nonresident parents spend time with their absent children. Results suggest that nonresident mothers and fathers exhibit a similar pattern of participation in activities with their absent children. Most nonresident parents either engage in only leisure activities with their children or have no contact. (Author/MKA)

  11. Thirst - absent

    MedlinePlus

    ... fluids? Did the loss of thirst follow a head injury? Do you have other symptoms such as abdominal ... do a detailed nervous system exam if a head injury or problem with the hypothalamus is suspected. Tests ...

  12. Subsurface geology of Corpus Christi Bay, Neuces County, Texas

    SciTech Connect

    Collins, J.W.

    1996-09-01

    Prolific production in Corpus Christi Bay has occurred mainly in the regressive Frio Barrier Bar System and the associated shore face-shelf environment. All production in Corpus Christi Bay area is below the Anahuac transgressive wedge with the greatest accumulation in the 1st Marg. sand, which has produced a minimum of 680 BCF of gas in the Red Fish Bay-Mustang Island Common 10 reservoir, the largest single reservoir in South Texas. The 1st Marg. sands have produced in excess of 990 BCFG from four fields in Corpus Christi Bay. Shallow hydrocarbons in Corpus Christi Bay are associated with the South Texas Frio Barrier Bar System and are structurally trapped on large fault bound anticlines or up-to-the-coast relief faults. Deeper production from the Frio Sands is mainly on the Barrier Bar shoreface and associated with fault bounded anticlinal closures. Structural complexity increases with depth especially along the large strike aligned growth faults, some up to 4000 ft displacement, and the associated rollover anticlines. subsidiary faults, and shale plugs. These deeper reservoirs are usually pressure-depletion drives. The oil industry can point with pride to the co-existence with the fragile bay environment while extracting huge reserves. Most of the wells are on State of Texas marine leases and are controlled by State rules and City of Corpus Christi Bay drilling ordinances.

  13. Transmutation Theory in the Greek Alchemical Corpus.

    PubMed

    Dufault, Olivier

    2015-08-01

    This paper studies transmutation theory as found in the texts attributed to Zosimus of Panopolis, "the philosopher Synesius," and "the philosopher Olympiodorus of Alexandria." It shows that transmutation theory (i.e. a theory explaining the complete transformation of substances) is mostly absent from the work attributed to these three authors. The text attributed to Synesius describes a gilding process, which is similar to those described by Pliny and Vitruvius. The commentary attributed to Olympiodorus is the only text studied here that describes something similar to a transmutation theory. It is unclear, however, if this was a theory of transmutation or if the writer meant something more like the literal meaning of the word "ekstrophē," a term used to describe the transformation of metals, as the "turning inside-out" of what is hidden in a substance. A similar conception of ekstrophē can be found in the works of Zosimus, who discussed transmutation to make an analogy with self-purification processes, which, from the perspective of his own anthropogony, consisted in the "turning inside-out" of the "inner human" (esō anthrōpos). PMID:26307909

  14. A multimodal corpus of speech to infant and adult listeners.

    PubMed

    Johnson, Elizabeth K; Lahey, Mybeth; Ernestus, Mirjam; Cutler, Anne

    2013-12-01

    An audio and video corpus of speech addressed to 28 11-month-olds is described. The corpus allows comparisons between adult speech directed toward infants, familiar adults, and unfamiliar adult addressees as well as of caregivers' word teaching strategies across word classes. Summary data show that infant-directed speech differed more from speech to unfamiliar than familiar adults, that word teaching strategies for nominals versus verbs and adjectives differed, that mothers mostly addressed infants with multi-word utterances, and that infants' vocabulary size was unrelated to speech rate, but correlated positively with predominance of continuous caregiver speech (not of isolated words) in the input. PMID:25669300

  15. The Use of Corpus Examples for Language Comprehension and Production

    ERIC Educational Resources Information Center

    Frankenberg-Garcia, Ana

    2014-01-01

    One of the many new features of English language learners' dictionaries derived from the technological developments that have taken place over recent decades is the presence of corpus-based examples to illustrate the use of words in context. However, empirical studies have generally not been able to produce conclusive evidence about their…

  16. Corpus Linguistics, Network Analysis and Co-Occurrence Matrices

    ERIC Educational Resources Information Center

    Stuart, Keith; Botella, Ana

    2009-01-01

    This article describes research undertaken in order to design a methodology for the reticular representation of knowledge of a specific discourse community. To achieve this goal, a representative corpus of the scientific production of the members of this discourse community (Universidad Politecnica de Valencia, UPV) was created. This article…

  17. The Dependency Structure of Coordinate Phrases: A Corpus Approach

    ERIC Educational Resources Information Center

    Temperley, David

    2005-01-01

    Hudson (1990) proposes that each conjunct in a coordinate phrase forms dependency relations with heads or dependents outside the coordinate phrase (the "multi-head" view). This proposal is tested through corpus analysis of Wall Street Journal text. For right-branching constituents (such as direct-object NPs), a short-long preference for conjunct…

  18. Combining text clustering and retrieval for corpus adaptation

    NASA Astrophysics Data System (ADS)

    He, Feng; Ding, Xiaoqing

    2007-01-01

    The application-relevant text data are very useful in various natural language applications. Using them can achieve significantly better performance for vocabulary selection, language modeling, which are widely employed in automatic speech recognition, intelligent input method etc. In some situations, however, the relevant data is hard to collect. Thus, the scarcity of application-relevant training text brings difficulty upon these natural language processing. In this paper, only using a small set of application specific text, by combining unsupervised text clustering and text retrieval techniques, the proposed approach can find the relevant text from unorganized large scale corpus, thereby, adapt training corpus towards the application area of interest. We use the performance of n-gram statistical language model, which is trained from the text retrieved and test on the application-specific text, to evaluate the relevance of the text acquired, accordingly, to validate the effectiveness of our corpus adaptation approach. The language models trained from the ranked text bundles present well discriminated perplexities on the application-specific text. The preliminary experiments on short message text and unorganized large corpus demonstrate the performance of the proposed methods.

  19. Touch. Talking About Non-Verbal Communication: A Corpus Study.

    ERIC Educational Resources Information Center

    Guo, Xiaotian

    1999-01-01

    Presents the third and final report of an analysis of nonverbal communication. In this report, the phrase "touch wood" is investigated using the Bank of English Corpus. The first two phrases examined were "shrug" and "hold one's gaze." Each of these phrases relates to an aspect of communication that may hold particular difficulties for someone…

  20. Shrug! Talking About Non-Verbal Communication: A Corpus Study.

    ERIC Educational Resources Information Center

    Guo, Xiaotin

    1999-01-01

    In this study, the phrase "shrug" is investigated using the Bank of English Corpus. The report is the first of three; the other two will focus on the phrases "hold one's gaze" and "touch wood." Each of these phrases relates to an aspect of communications that may hold particular difficulties for someone from another culture: gesture, eye contact,…

  1. Dative Alternation in Indian English: A Corpus-Based Analysis

    ERIC Educational Resources Information Center

    De Cuypere, Ludovic; Verbeke, Saartje

    2013-01-01

    The dative alternation refers to the alternation between two constructions that denote some type of transfer: the double object construction ("I give my sister a book") vs. the to-dative construction ("I give a book to my sister"). We examined the motivations behind the dative alternation in Indian English. A corpus study was performed based on a…

  2. Semantic Associations in Business English: A Corpus-Based Analysis

    ERIC Educational Resources Information Center

    Nelson, Mike

    2006-01-01

    This paper examines the semantic associations of words found in the business lexical environment by using a one-million word corpus of both spoken and written Business English. The key method of analysis is that of semantic prosody or semantic association; the notion that words associate with collocates that are themselves related, often either…

  3. Corpus Consultation and Advanced Learners' Writing Skills in French

    ERIC Educational Resources Information Center

    Chambers, Angela; O'Sullivan, Ide

    2004-01-01

    In the rapidly changing environment of language learning and teaching, electronic literacies have an increasingly important role to play. While much research on new literacies focuses on the World Wide Web, the aim in this study is to investigate the importance of corpus consultation as a new type of literacy which is of particular relevance in…

  4. A Corpus-Based Comparative Study of "Learn" and "Acquire"

    ERIC Educational Resources Information Center

    Yang, Bei

    2016-01-01

    As an important yet intricate linguistic feature in English language, synonymy poses a great challenge for second language learners. Using the 100 million-word British National Corpus (BNC) as data and the software Sketch Engine (SkE) as an analyzing tool, this article compares the usage of "learn" and "acquire" used in natural…

  5. A Multidimensional Analysis of a Written L2 Spanish Corpus

    ERIC Educational Resources Information Center

    Asencion-Delaney, Yuly; Collentine, Joseph

    2011-01-01

    The present study adds to our understanding of how learners employ lexical and grammatical phenomena to communicate in writing in different types of interlanguage discourse. A multidimensional (factor) analysis of a corpus of L2 Spanish writing (202,241 words) generated by second- and third-year, university-level learners was performed. The…

  6. Corpus-Based Learning of Cantonese for Mandarin Speakers

    ERIC Educational Resources Information Center

    Wong, Tak-Sum; Lee, John S. Y.

    2016-01-01

    This article presents the first study on using a parallel corpus to teach Cantonese, the variety of Chinese spoken in Hong Kong. We evaluated this approach with Mandarin-speaking undergraduate students at the beginner level. Exploiting their knowledge of Mandarin, a closely related language, the students studied Cantonese with authentic material…

  7. Using On-line Corpus To Facilitate Language Learning.

    ERIC Educational Resources Information Center

    Sun, Yu-Chih

    The potential for on-line corpus in language teaching and learning has been the focus of attention on the part of teachers and researchers for some time now. The purpose of this study is to report on an Internet-based concordance approach to language learning and to investigate both qualitatively and quantitatively Taiwanese…

  8. An integrated pharmacokinetics ontology and corpus for text mining

    PubMed Central

    2013-01-01

    Background Drug pharmacokinetics parameters, drug interaction parameters, and pharmacogenetics data have been unevenly collected in different databases and published extensively in the literature. Without appropriate pharmacokinetics ontology and a well annotated pharmacokinetics corpus, it will be difficult to develop text mining tools for pharmacokinetics data collection from the literature and pharmacokinetics data integration from multiple databases. Description A comprehensive pharmacokinetics ontology was constructed. It can annotate all aspects of in vitro pharmacokinetics experiments and in vivo pharmacokinetics studies. It covers all drug metabolism and transportation enzymes. Using our pharmacokinetics ontology, a PK-corpus was constructed to present four classes of pharmacokinetics abstracts: in vivo pharmacokinetics studies, in vivo pharmacogenetic studies, in vivo drug interaction studies, and in vitro drug interaction studies. A novel hierarchical three level annotation scheme was proposed and implemented to tag key terms, drug interaction sentences, and drug interaction pairs. The utility of the pharmacokinetics ontology was demonstrated by annotating three pharmacokinetics studies; and the utility of the PK-corpus was demonstrated by a drug interaction extraction text mining analysis. Conclusions The pharmacokinetics ontology annotates both in vitro pharmacokinetics experiments and in vivo pharmacokinetics studies. The PK-corpus is a highly valuable resource for the text mining of pharmacokinetics parameters and drug interactions. PMID:23374886

  9. Corpus Planning for the Southern Peruvian Quechua Language.

    ERIC Educational Resources Information Center

    Coronel-Molina, Serafin M.

    1997-01-01

    The discussion of corpus planning for the Southern Quechua language variety of Peru examines issues of graphization, standardization, modernization, and renovation of Quechua in the face of increasing domination by the Spanish language. The efforts of three major groups of linguists and other scholars working on language planning in Peru, and the…

  10. Motivating College Students' Learning English for Specific Purposes Courses through Corpus Building

    ERIC Educational Resources Information Center

    Wu, Lin-Fang

    2014-01-01

    This study was conducted to determine how to motivate technical college students to learn English for specific purposes (ESP) courses through corpus building and enhance their language proficiency during the coursework for their majors. This study explores corpus building skills, how to simplify ESP courses by corpus building for English as second…

  11. Separating Fact and Fiction: The Real Story of Corpus Use in Language Teaching

    ERIC Educational Resources Information Center

    Boulton, Alex

    2013-01-01

    This paper investigates uses of corpora in language learning ("data-driven learning") through analysis of a 600K-word corpus of empirical research papers in the field. The corpus can tell us much--the authors and the countries the studies are conducted in, the types of publication, and so on. The corpus investigation itself starts with…

  12. Computer-assisted Lemmatisation of a Cornish Text Corpus for Lexicographical Purposes

    ERIC Educational Resources Information Center

    Mills, Jon

    2002-01-01

    This project sets out to discover and develop techniques for the lemmatisation of a historical corpus of the Cornish language in order that a lemmatised dictionary macrostructure can be generated from the corpus. The system should be capable of uniquely identifying every lexical item that is attested in the corpus. A survey of published and…

  13. Evaluating Corpus Literacy Training for Pre-Service Language Teachers: Six Case Studies

    ERIC Educational Resources Information Center

    Heather, Julian; Helt, Marie

    2012-01-01

    Corpus literacy is the ability to use corpora--large, principled databases of spoken and written language--for language analysis and instruction. While linguists have emphasized the importance of corpus training in teacher preparation programs, few studies have investigated the process of initiating teachers into corpus literacy with the result…

  14. Corpus-Based Research and Pedagogy in EAP: From Lexis to Genre

    ERIC Educational Resources Information Center

    Flowerdew, Lynne

    2015-01-01

    This plenary paper showcases current corpus-based research on written academic English, illustrating the tight links that exist between corpus research and pedagogic applications. I first explicate Sinclair's concept of the "lexical approach", which underpins much corpus research and pedagogy. I then discuss studies which focus on…

  15. The role of GPR1 signaling in mice corpus luteum.

    PubMed

    Yang, Ya-Li; Ren, Li-Rong; Sun, Li-Feng; Huang, Chen; Xiao, Tian-Xia; Wang, Bao-Bei; Chen, Jie; Zabel, Brian A; Ren, Peigen; Zhang, Jian V

    2016-07-01

    Chemerin, a chemokine, plays important roles in immune responses, inflammation, adipogenesis, and carbohydrate metabolism. Our recent research has shown that chemerin has an inhibitory effect on hormone secretion from the testis and ovary. However, whether G protein-coupled receptor 1 (GPR1), the active receptor for chemerin, regulates steroidogenesis and luteolysis in the corpus luteum is still unknown. In this study, we established a pregnant mare serum gonadotropin-human chorionic gonadotropin (PMSG-hCG) superovulation model, a prostaglandin F2α (PGF2α) luteolysis model, and follicle and corpus luteum culture models to analyze the role of chemerin signaling through GPR1 in the synthesis and secretion of gonadal hormones during follicular/luteal development and luteolysis. Our results, for the first time, show that chemerin and GPR1 are both differentially expressed in the ovary over the course of the estrous cycle, with highest levels in estrus and metestrus. GPR1 has been localized to granulosa cells, cumulus cells, and the corpus luteum by immunohistochemistry (IHC). In vitro, we found that chemerin suppresses hCG-induced progesterone production in cultured follicle and corpus luteum and that this effect is attenuated significantly by anti-GPR1 MAB treatment. Furthermore, when the phosphoinositide 3-kinase (PI3K) pathway was blocked, the attenuating effect of GPR1 MAB was abrogated. Interestingly, PGF2α induces luteolysis through activation of caspase-3, leading to a reduction in progesterone secretion. Treatment with GPR1 MAB blocked the PGF2α effect on caspase-3 expression and progesterone secretion. This study indicates that chemerin/GPR1 signaling directly or indirectly regulates progesterone synthesis and secretion during the processes of follicular development, corpus luteum formation, and PGF2α-induced luteolysis. PMID:27149986

  16. Formulaic Language and Collocations in German Essays: From Corpus-Driven Data to Corpus-Based Materials

    ERIC Educational Resources Information Center

    Krummes, Cedric; Ensslin, Astrid

    2015-01-01

    Whereas there exists a plethora of research on collocations and formulaic language in English, this article contributes towards a somewhat less developed area: the understanding and teaching of formulaic language in German as a foreign language. It analyses formulaic sequences and collocations in German writing (corpus-driven) and provides modern…

  17. Using Google as a Super Corpus to Drive Written Language Learning: A Comparison with the British National Corpus

    ERIC Educational Resources Information Center

    Sha, Guoquan

    2010-01-01

    Data-driven learning (DDL), or corpus-based language learning, involves the learner in an exploratory task to discover appropriate expressions or collocates regarding his writing. However, the problematic units of meaning in each learner's writing are so diverse that conventional corpora often prove futile. The search engine Google with the…

  18. Case Study: The Perception of Online Tutorials--Habitually Absent Students with Familial or Socioeconomic Circumstances

    ERIC Educational Resources Information Center

    Hudson, Glyniss A.

    2013-01-01

    This case study explored the perception of online tutorials by habitually absent students with familial or socioeconomic circumstances. Researched literature confirmed a link between absenteeism, and academic achievement. Research Questions were designed to determine (a) student perception of online tutorials, and (b) motivation to achieve…

  19. Aortic coarctation associated with an absent segment of the proximal right subclavian artery.

    PubMed

    Jasper, A; Keshava, S N

    2014-01-01

    Coarctation of the aorta is a congenital anomaly of the thoracic aorta with many known associations. We describe the case of a young man referred for management of subarachnoid hemorrhage, in whom subsequent work-up revealed the previously undescribed combination of severe postductal aortic coarctation and an absent segment of the proximal right subclavian artery. PMID:25370550

  20. Absent Does Not Equal Uninvolved: Predictors of Fathering in Teen Mother Families.

    ERIC Educational Resources Information Center

    Danziger, Sandra K.; Radin, Norma

    1990-01-01

    Examined effects of several predictors of father involvement in large sample of single-parent, teenage mother families (N=289). The results of telephone interviews indicated that work behavior of absent fathers had a significant direct effect on participation in childrearing and that minority mothers reported higher rates of paternal involvement.…

  1. The Absent Father: Gender Identity Considerations for Art Therapists Working with Adolescent Boys.

    ERIC Educational Resources Information Center

    Haeseler, Martha

    1996-01-01

    Recent research has shown that boys from father-absent homes exhibit greater feminine role identification, delinquency, mental disorders, poor academic performance, and poor self-esteem. This article presents case studies that demonstrate crises of masculine identification for adolescent boys whose lives lack either a present father or male…

  2. Aortic root replacement with absent left-main coronary artery: how to do it.

    PubMed

    Saha, Kamales Kumar; Parate, Bhupesh; Jagiasi, Bharat

    2015-02-01

    Aortic root replacement in patient with a coronary artery anomaly can be challenging. We describe aortic root replacement in a patient with annuloaortic ectasia and coarctation, who had an absent left main coronary artery. There were separate origins of the left anterior descending and left circumflex coronary arteries from the aorta. The technical modification employed in this case is discussed. PMID:24887871

  3. When Familiar Is Not Better: 12-Month-Old Infants Respond to Talk about Absent Objects

    ERIC Educational Resources Information Center

    Osina, Maria A.; Saylor, Megan M.; Ganea, Patricia A.

    2013-01-01

    Three experiments that demonstrate a novel constraint on infants' language skills are described. Across the experiments it is shown that as babies near their 1st birthday, their ability to respond to talk about an absent object is influenced by a referent's spatiotemporal history: familiarizing infants with an object in 1 or several nontest…

  4. Cholinergic neurotransmission in human corpus cavernosum. II. Acetylcholine synthesis

    SciTech Connect

    Blanco, R.; De Tejada, S.; Goldstein, I.; Krane, R.J.; Wotiz, H.H.; Cohen, R.A. )

    1988-03-01

    Physiological and histochemical evidence indicates that cholinergic nerves may participate in mediating penile erection. Acetylcholine synthesis and release was studied in isolated human corporal tissue. Human corpus cavernosum incubated with ({sup 3}H)choline accumulated ({sup 3}H)choline and synthesized ({sup 3}H)acethylcholine in an concentration-dependent manner. ({sup 3}H)Acetylcholine accumulation by the tissue was inhibited by hemicholinium-3, a specific antagonist of the high-affinity choline transport in cholinergic nerves. Transmural electrical field stimulation caused release of ({sup 3}H)acetylcholine which was significantly diminished by inhibiting neurotransmission with calcium-free physiological salt solution or tetrodotoxin. These observations provide biochemical and physiological evidence for the existence of cholinergic innervation in human corpus cavernosum.

  5. Frequency of Basic English Grammatical Structures: A Corpus Analysis

    PubMed Central

    Roland, Douglas; Dick, Frederic; Elman, Jeffrey L.

    2009-01-01

    Many recent models of language comprehension have stressed the role of distributional frequencies in determining the relative accessibility or ease of processing associated with a particular lexical item or sentence structure. However, there exist relatively few comprehensive analyses of structural frequencies, and little consideration has been given to the appropriateness of using any particular set of corpus frequencies in modeling human language. We provide a comprehensive set of structural frequencies for a variety of written and spoken corpora, focusing on structures that have played a critical role in debates on normal psycholinguistics, aphasia, and child language acquisition, and compare our results with those from several recent papers to illustrate the implications and limitations of using corpus data in psycholinguistic research. PMID:19668599

  6. Corpus annotation for mining biomedical events from literature

    PubMed Central

    Kim, Jin-Dong; Ohta, Tomoko; Tsujii, Jun'ichi

    2008-01-01

    Background Advanced Text Mining (TM) such as semantic enrichment of papers, event or relation extraction, and intelligent Question Answering have increasingly attracted attention in the bio-medical domain. For such attempts to succeed, text annotation from the biological point of view is indispensable. However, due to the complexity of the task, semantic annotation has never been tried on a large scale, apart from relatively simple term annotation. Results We have completed a new type of semantic annotation, event annotation, which is an addition to the existing annotations in the GENIA corpus. The corpus has already been annotated with POS (Parts of Speech), syntactic trees, terms, etc. The new annotation was made on half of the GENIA corpus, consisting of 1,000 Medline abstracts. It contains 9,372 sentences in which 36,114 events are identified. The major challenges during event annotation were (1) to design a scheme of annotation which meets specific requirements of text annotation, (2) to achieve biology-oriented annotation which reflect biologists' interpretation of text, and (3) to ensure the homogeneity of annotation quality across annotators. To meet these challenges, we introduced new concepts such as Single-facet Annotation and Semantic Typing, which have collectively contributed to successful completion of a large scale annotation. Conclusion The resulting event-annotated corpus is the largest and one of the best in quality among similar annotation efforts. We expect it to become a valuable resource for NLP (Natural Language Processing)-based TM in the bio-medical domain. PMID:18182099

  7. Anaphoric relations in the clinical narrative: corpus creation

    PubMed Central

    Chapman, Wendy W; Zheng, Jiaping; Crowley, Rebecca S

    2011-01-01

    Objective The long-term goal of this work is the automated discovery of anaphoric relations from the clinical narrative. The creation of a gold standard set from a cross-institutional corpus of clinical notes and high-level characteristics of that gold standard are described. Methods A standard methodology for annotation guideline development, gold standard annotations, and inter-annotator agreement (IAA) was used. Results The gold standard annotations resulted in 7214 markables, 5992 pairs, and 1304 chains. Each report averaged 40 anaphoric markables, 33 pairs, and seven chains. The overall IAA is high on the Mayo dataset (0.6607), and moderate on the University of Pittsburgh Medical Center (UPMC) dataset (0.4072). The IAA between each annotator and the gold standard is high (Mayo: 0.7669, 0.7697, and 0.9021; UPMC: 0.6753 and 0.7138). These results imply a quality corpus feasible for system development. They also suggest the complementary nature of the annotations performed by the experts and the importance of an annotator team with diverse knowledge backgrounds. Limitations Only one of the annotators had the linguistic background necessary for annotation of the linguistic attributes. The overall generalizability of the guidelines will be further strengthened by annotations of data from additional sites. This will increase the overall corpus size and the representation of each relation type. Conclusion The first step toward the development of an anaphoric relation resolver as part of a comprehensive natural language processing system geared specifically for the clinical narrative in the electronic medical record is described. The deidentified annotated corpus will be available to researchers. PMID:21459927

  8. Annotated chemical patent corpus: a gold standard for text mining.

    PubMed

    Akhondi, Saber A; Klenner, Alexander G; Tyrchan, Christian; Manchala, Anil K; Boppana, Kiran; Lowe, Daniel; Zimmermann, Marc; Jagarlapudi, Sarma A R P; Sayle, Roger; Kors, Jan A; Muresan, Sorel

    2014-01-01

    Exploring the chemical and biological space covered by patent applications is crucial in early-stage medicinal chemistry activities. Patent analysis can provide understanding of compound prior art, novelty checking, validation of biological assays, and identification of new starting points for chemical exploration. Extracting chemical and biological entities from patents through manual extraction by expert curators can take substantial amount of time and resources. Text mining methods can help to ease this process. To validate the performance of such methods, a manually annotated patent corpus is essential. In this study we have produced a large gold standard chemical patent corpus. We developed annotation guidelines and selected 200 full patents from the World Intellectual Property Organization, United States Patent and Trademark Office, and European Patent Office. The patents were pre-annotated automatically and made available to four independent annotator groups each consisting of two to ten annotators. The annotators marked chemicals in different subclasses, diseases, targets, and modes of action. Spelling mistakes and spurious line break due to optical character recognition errors were also annotated. A subset of 47 patents was annotated by at least three annotator groups, from which harmonized annotations and inter-annotator agreement scores were derived. One group annotated the full set. The patent corpus includes 400,125 annotations for the full set and 36,537 annotations for the harmonized set. All patents and annotated entities are publicly available at www.biosemantics.org. PMID:25268232

  9. An Integration of Corpus-Based and Genre-Based Approaches to Text Analysis in Eap/esp: Countering Criticisms against Corpus-Based Methodologies

    ERIC Educational Resources Information Center

    Flowerdew, L.

    2005-01-01

    In the past few years, several corpus-based studies have been carried out which either explicitly in some cases, but more subtly in others, draw on aspects of genre theory for their analyses. The purpose of this paper is to review those corpus studies which specifically draw on either the English for Specific Purposes (following the Swales…

  10. [The pathways of glucose catabolism in Tenebrio molitor: the effects of fasting and the injection of the corpus cardiacum-corpus allatum complex].

    PubMed

    Gourdoux, L

    1975-01-01

    In the adult of Tenebrio molitor (Coleopterous) the pentose cycle is greatly used for the glucose degradation: starvation or injection of corpus cardiacum-corpus allatum complex alter this metabolic orientation : the pentose pathway is decreased and the glucose itself is less utilized. PMID:129268

  11. Recent Developments in Corpus Linguistics and Corpus-Based Research/Department of Linguistics and Modern Language Studies at the Hong Kong Institute of Education

    ERIC Educational Resources Information Center

    Xie, Qin

    2015-01-01

    Corpus linguistics has transformed the landscape of empirical research on languages in recent decades. The proliferation of corpus technology has enabled researchers worldwide to conduct research in their own geographical locations with few hindrances. It has become increasingly commonplace for researchers to compile their own corpora for specific…

  12. Exploring What's Missing: What Do Target Absent Trials Reveal About Autism Search Superiority?

    PubMed

    Keehn, Brandon; Joseph, Robert M

    2016-05-01

    We used eye-tracking to investigate the roles of enhanced discrimination and peripheral selection in superior visual search in autism spectrum disorder (ASD). Children with ASD were faster at visual search than their typically developing peers. However, group differences in performance and eye-movements did not vary with the level of difficulty of discrimination or selection. Rather, consistent with prior ASD research, group differences were mainly the effect of faster performance on target-absent trials. Eye-tracking revealed a lack of left-visual-field search asymmetry in ASD, which may confer an additional advantage when the target is absent. Lastly, ASD symptomatology was positively associated with search superiority, the mechanisms of which may shed light on the atypical brain organization that underlies social-communicative impairment in ASD. PMID:26762114

  13. Absent upper blind Pouch in a case of tracheo-esophageal fistula.

    PubMed

    Harjai, Man Mohan; Badal, Sachendra; Khanna, Sangeeta; Singh, Ajit Kumar

    2015-01-01

    A common upper airway and digestive tract is a rare congenital anomaly that is usually fatal and its exact incidence is not known. It is a diagnostic challenge as it requires high index of suspicion. It should be considered in a neonate with respiratory distress in a non-vigorous baby requiring endotracheal intubation, which is difficult even in expert hand. We present a newborn with suspected tracheo-esophageal fistula that was diagnosed intraoperatively to have absent upper blind pouch of the esophagus and on autopsy found to have laryngeal atresia with absent vocal cords and a common aerodigestive tract continuing distally with trachea. The neonate was ventilated with endotracheal tube (ETT) placement which in retrospect we came to know that it was in the esophagus. The neonate also had associated multiple congenital anomalies of VACTERL association. The importance of teamwork between neonatologist, pediatric surgeon, anesthesiologist, and radiologist is highlighted for diagnosis and management of such rare cases. PMID:25552830

  14. PHACE(S) Syndrome With Absent Intracranial Internal Carotid Artery and Anomalous Circle of Willis.

    PubMed

    Winter, Pieta R; Itinteang, Tinte; Leadbitter, Philip; FitzJohn, Trevor; Tan, Swee T

    2015-06-01

    The authors present a case of PHACE(S) (posterior fossa malformations, hemangioma, arterial anomalies, cardiac defects, eye anomalies, and sternal cleft or supraumbilical raphe) syndrome with a right-sided segmental infantile hemangioma, and describe in detail, the associated absent ipsilateral intracranial internal carotid artery and anomalous Circle of Willis. Propranolol therapy led to accelerated, complete involution. Nadolol may reduce the theoretical risk of treating PHACE(S) patients with β-blockers. PMID:26080245

  15. Surgical treatment of tetralogy of Fallot with absent pulmonary valve syndrome.

    PubMed

    Tanaka, Yuki; Miyamoto, Takashi; Naito, Yuji; Yoshitake, Shuichi

    2016-06-01

    The patient was a 3-month-old girl weighting 3.6 kg, diagnosed with tetralogy of Fallot and absent pulmonary valve syndrome. We surgically repaired the tetralogy of Fallot by patch closure of the ventricular septal defect, right ventricular outflow tract reconstruction using an expanded polytetrafluoroethylene monocusp patch with a bulging sinus, and removal of the bronchial obstruction by anterior translocation of the pulmonary artery using the Lecompte maneuver. PMID:25792545

  16. Cardiac-locked bursts of muscle sympathetic nerve activity are absent in familial dysautonomia

    PubMed Central

    Macefield, Vaughan G; Norcliffe-Kaufmann, Lucy; Axelrod, Felicia B; Kaufmann, Horacio

    2013-01-01

    Familial dysautonomia (Riley–Day syndrome) is an hereditary sensory and autonomic neuropathy (HSAN type III), expressed at birth, that is associated with reduced pain and temperature sensibilities and absent baroreflexes, causing orthostatic hypotension as well as labile blood pressure that increases markedly during emotional excitement. Given the apparent absence of functional baroreceptor afferents, we tested the hypothesis that the normal cardiac-locked bursts of muscle sympathetic nerve activity (MSNA) are absent in patients with familial dysautonomia. Tungsten microelectrodes were inserted percutaneously into muscle or cutaneous fascicles of the common peroneal nerve in 12 patients with familial dysautonomia. Spontaneous bursts of MSNA were absent in all patients, but in five patients we found evidence of tonically firing sympathetic neurones, with no cardiac rhythmicity, that increased their spontaneous discharge during emotional arousal but not during a manoeuvre that unloads the baroreceptors. Conversely, skin sympathetic nerve activity (SSNA), recorded in four patients, appeared normal. We conclude that the loss of phasic bursts of MSNA and the loss of baroreflex modulation of muscle vasoconstrictor drive contributes to the poor control of blood pressure in familial dysautonomia, and that the increase in tonic firing of muscle vasoconstrictor neurones contributes to the increase in blood pressure during emotional excitement. PMID:23165765

  17. Gender-based violence and absent fathers: a scoping review protocol

    PubMed Central

    Sikweyiya, Yandisa; Nduna, Mzikazi; Khuzwayo, Nelisiwe; Mthombeni, Andile; Mashamba-Thompson, Tivani Phosa

    2016-01-01

    Introduction Gender-based violence (GBV) and absent fathers are two epidemics that affect women and children in sub-Saharan Africa. However, the understanding of the complex links between GBV and absent fathers is currently inadequate. The aim of the study is to provide an overview of documented evidence that links GBV and absent fathers as well as identifies areas that require systematic review and where more primary research is needed. Methods and analysis The search strategy for this scoping review study will involve electronic databases including: Academic Search Premier, Ingenta, Kluwer Online, PsycARTICLES (EBSCO), PsycINFO (EBSCO), Social Work Abstracts and Sociological Collection. The studies will be mapped in 2 stages: stage 1 will map studies descriptively by focus and method; stage 2 will involve additional inclusion criteria, quality assessment and data extraction undertaken by two reviewers in parallel. A thematic analysis of the studies will be carried out to extract relevant outcomes using NVIVO. Discussion We anticipate finding a large number of studies on GBV diagnostic interventions in sub-Saharan Africa which, once summarised, will be useful to guide future research. The protocol for the scoping review has been registered in PROSPERO. Dissemination The study will be disseminated electronically and in print. It will also be presented to conferences related to GBV, Father Connections and Children's Health. PROSPERO registration number CRD42015022094. PMID:27297007

  18. The bulk and the tail of minimal absent words in genome sequences

    NASA Astrophysics Data System (ADS)

    Aurell, Erik; Innocenti, Nicolas; Zhou, Hai-Jun

    2016-04-01

    Minimal absent words (MAW) of a genomic sequence are subsequences that are absent themselves but the subwords of which are all present in the sequence. The characteristic distribution of genomic MAWs as a function of their length has been observed to be qualitatively similar for all living organisms, the bulk being rather short, and only relatively few being long. It has been an open issue whether the reason behind this phenomenon is statistical or reflects a biological mechanism, and what biological information is contained in absent words. In this work we demonstrate that the bulk can be described by a probabilistic model of sampling words from random sequences, while the tail of long MAWs is of biological origin. We introduce the concept of a core of a MAW, which are sequences present in the genome and closest to a given MAW. We show that in E. faecalis, E. coli and yeast the cores of the longest MAWs, which exist in two or more copies, are located in highly conserved regions the most prominent example being ribosomal RNAs. We also show that while the distribution of the cores of long MAWs is roughly uniform over these genomes on a coarse-grained level, on a more detailed level it is strongly enhanced in 3’ untranslated regions (UTRs) and, to a lesser extent, also in 5’ UTRs. This indicates that MAWs and associated MAW cores correspond to fine-tuned evolutionary relationships, and suggest that they can be more widely used as markers for genomic complexity.

  19. The bulk and the tail of minimal absent words in genome sequences.

    PubMed

    Aurell, Erik; Innocenti, Nicolas; Zhou, Hai-Jun

    2016-04-01

    Minimal absent words (MAW) of a genomic sequence are subsequences that are absent themselves but the subwords of which are all present in the sequence. The characteristic distribution of genomic MAWs as a function of their length has been observed to be qualitatively similar for all living organisms, the bulk being rather short, and only relatively few being long. It has been an open issue whether the reason behind this phenomenon is statistical or reflects a biological mechanism, and what biological information is contained in absent words. In this work we demonstrate that the bulk can be described by a probabilistic model of sampling words from random sequences, while the tail of long MAWs is of biological origin. We introduce the concept of a core of a MAW, which are sequences present in the genome and closest to a given MAW. We show that in E. faecalis, E. coli and yeast the cores of the longest MAWs, which exist in two or more copies, are located in highly conserved regions the most prominent example being ribosomal RNAs. We also show that while the distribution of the cores of long MAWs is roughly uniform over these genomes on a coarse-grained level, on a more detailed level it is strongly enhanced in 3' untranslated regions (UTRs) and, to a lesser extent, also in 5' UTRs. This indicates that MAWs and associated MAW cores correspond to fine-tuned evolutionary relationships, and suggest that they can be more widely used as markers for genomic complexity. PMID:27043075

  20. Endocrine and Local Control of the Primate Corpus Luteum

    PubMed Central

    Stouffer, Richard L.; Bishop, Cecily V.; Bogan, Randy L.; Xu, Fuhua; Hennebold, Jon D.

    2014-01-01

    The primate corpus luteum is a transient endocrine gland that differentiates from the ovulatory follicle midway through the ovarian (menstrual) cycle. Its formation and limited lifespan is critical for fertility, as luteal-derived progesterone is the essential steroid hormone required for embryo implantation and maintenance of intra-uterine pregnancy until the placenta develops. It is well-established that LH and the LH-like hormone, CG, are the vital luteotropic hormones during the menstrual cycle and early pregnancy, respectively. Recent advances, particularly through genome analyses and cellular studies, increased our understanding of various local factors and cellular processes associated with the development, maintenance and repression of the corpus luteum. These include paracrine or autocrine factors associated with angiogenesis (e.g., VEGF), and that mediate LH/CG actions (e.g., progesterone), or counteract luteotropic effects (i.e., local luteolysis; e.g., PGF2α). However, areas of mystery and controversy remain, particularly regarding the signals and events that initiate luteal regression in the non-fecund cycle. Novel approaches capable of gene “knockdown” or amplification”, in vivo as well as in vitro, should identify novel or underappreciated gene products that are regulated by or modulate LH/CG actions to control the functional lifespan of the primate corpus luteum. Further advances in our understanding of luteal physiology will help to improve or control fertility for purposes ranging from preservation of endangered primate species to designing novel ovary-based contraceptives and treating ovarian disorders in women. R01 HD020869, R01 HD042000, U54 HD018185, U54 HD055744, P51 OD011092, T32 HD007133, Bayer Schering Pharma AG. PMID:24287034

  1. Construction of an annotated corpus to support biomedical information extraction

    PubMed Central

    Thompson, Paul; Iqbal, Syed A; McNaught, John; Ananiadou, Sophia

    2009-01-01

    Background Information Extraction (IE) is a component of text mining that facilitates knowledge discovery by automatically locating instances of interesting biomedical events from huge document collections. As events are usually centred on verbs and nominalised verbs, understanding the syntactic and semantic behaviour of these words is highly important. Corpora annotated with information concerning this behaviour can constitute a valuable resource in the training of IE components and resources. Results We have defined a new scheme for annotating sentence-bound gene regulation events, centred on both verbs and nominalised verbs. For each event instance, all participants (arguments) in the same sentence are identified and assigned a semantic role from a rich set of 13 roles tailored to biomedical research articles, together with a biological concept type linked to the Gene Regulation Ontology. To our knowledge, our scheme is unique within the biomedical field in terms of the range of event arguments identified. Using the scheme, we have created the Gene Regulation Event Corpus (GREC), consisting of 240 MEDLINE abstracts, in which events relating to gene regulation and expression have been annotated by biologists. A novel method of evaluating various different facets of the annotation task showed that average inter-annotator agreement rates fall within the range of 66% - 90%. Conclusion The GREC is a unique resource within the biomedical field, in that it annotates not only core relationships between entities, but also a range of other important details about these relationships, e.g., location, temporal, manner and environmental conditions. As such, it is specifically designed to support bio-specific tool and resource development. It has already been used to acquire semantic frames for inclusion within the BioLexicon (a lexical, terminological resource to aid biomedical text mining). Initial experiments have also shown that the corpus may viably be used to train IE

  2. Unsupervised Chunking Based on Graph Propagation from Bilingual Corpus

    PubMed Central

    Chao, Lidia S.

    2014-01-01

    This paper presents a novel approach for unsupervised shallow parsing model trained on the unannotated Chinese text of parallel Chinese-English corpus. In this approach, no information of the Chinese side is applied. The exploitation of graph-based label propagation for bilingual knowledge transfer, along with an application of using the projected labels as features in unsupervised model, contributes to a better performance. The experimental comparisons with the state-of-the-art algorithms show that the proposed approach is able to achieve impressive higher accuracy in terms of F-score. PMID:24772017

  3. Leg ulceration in chronic venous insufficiency caused by an absent inferior vena cava.

    PubMed

    Amano, Hiroo; Nagai, Yayoi; Endo, Yukie; Iwasaki, Tomoko; Ishikawa, Osamu

    2009-01-01

    We report here the case of a 55-year-old Japanese man with a one-year history of multiple ulcers on the left crural region. He had had pronounced varicose veins on both legs and the abdominal region for 35 years. Computed tomography images of the thoracic and abdominal regions showed the absence of an inferior vena cava, with pronounced dilatation of paravertebral venous plexus, cutaneous and azygous veins. Conservative topical treatments led to complete healing of the ulcers in one month. An absent inferior vena cava is an uncommon abnormality, often complicated by cardiac and other visceral malformations. It is a rare cause of chronic leg ulcers. PMID:19734977

  4. A human language corpus for interstellar message construction

    NASA Astrophysics Data System (ADS)

    Elliott, John

    2011-02-01

    The aim of HuLCC (the human language chorus corpus), is to provide a resource of sufficient size to facilitate inter-language analysis by incorporating languages from all the major language families: for the first time all aspects of typology will be incorporated within a single corpus, adhering to a consistent grammatical classification and granularity, which historically adopt a plethora of disparate schemes. An added feature will be the inclusion of a common text element, which will be translated across all languages, to provide a precise comparable thread for detailed linguistic analysis for translation strategies and a mechanism by which these mappings can be explicitly achieved. Methods developed to solve unambiguous mappings across these languages can then be adopted for any subsequent message authored by the SETI community. Initially, it is planned to provide at least 20,000 words for each chosen language, as this amount of text exceeds the point where randomly generated text can be disambiguated from natural language and is of sufficient size useful for message transmission [1] (Elliot, 2002). This paper details the design of this resource, which ultimately will be made available to SETI upon its completion, and discusses issues 'core' to any message construction.

  5. Macrophages regulate corpus luteum development during embryo implantation in mice

    PubMed Central

    Care, Alison S.; Diener, Kerrilyn R.; Jasper, Melinda J.; Brown, Hannah M.; Ingman, Wendy V.; Robertson, Sarah A.

    2013-01-01

    Macrophages are prominent in the uterus and ovary at conception. Here we utilize the Cd11b-Dtr mouse model of acute macrophage depletion to define the essential role of macrophages in early pregnancy. Macrophage depletion after conception caused embryo implantation arrest associated with diminished plasma progesterone and poor uterine receptivity. Implantation failure was alleviated by administration of bone marrow–derived CD11b+F4/80+ monocytes/macrophages. In the ovaries of macrophage-depleted mice, corpora lutea were profoundly abnormal, with elevated Ptgs2, Hif1a, and other inflammation and apoptosis genes and with diminished expression of steroidogenesis genes Star, Cyp11a1, and Hsd3b1. Infertility was rescued by exogenous progesterone, which confirmed that uterine refractoriness was fully attributable to the underlying luteal defect. In normally developing corpora lutea, macrophages were intimately juxtaposed with endothelial cells and expressed the proangiogenic marker TIE2. After macrophage depletion, substantial disruption of the luteal microvascular network occurred and was associated with altered ovarian expression of genes that encode vascular endothelial growth factors. These data indicate a critical role for macrophages in supporting the extensive vascular network required for corpus luteum integrity and production of progesterone essential for establishing pregnancy. Our findings raise the prospect that disruption of macrophage-endothelial cell interactions underpinning corpus luteum development contributes to infertility in women in whom luteal insufficiency is implicated. PMID:23867505

  6. Macrophages regulate corpus luteum development during embryo implantation in mice.

    PubMed

    Care, Alison S; Diener, Kerrilyn R; Jasper, Melinda J; Brown, Hannah M; Ingman, Wendy V; Robertson, Sarah A

    2013-08-01

    Macrophages are prominent in the uterus and ovary at conception. Here we utilize the Cd11b-Dtr mouse model of acute macrophage depletion to define the essential role of macrophages in early pregnancy. Macrophage depletion after conception caused embryo implantation arrest associated with diminished plasma progesterone and poor uterine receptivity. Implantation failure was alleviated by administration of bone marrow-derived CD11b+F4/80+ monocytes/macrophages. In the ovaries of macrophage-depleted mice, corpora lutea were profoundly abnormal, with elevated Ptgs2, Hif1a, and other inflammation and apoptosis genes and with diminished expression of steroidogenesis genes Star, Cyp11a1, and Hsd3b1. Infertility was rescued by exogenous progesterone, which confirmed that uterine refractoriness was fully attributable to the underlying luteal defect. In normally developing corpora lutea, macrophages were intimately juxtaposed with endothelial cells and expressed the proangiogenic marker TIE2. After macrophage depletion, substantial disruption of the luteal microvascular network occurred and was associated with altered ovarian expression of genes that encode vascular endothelial growth factors. These data indicate a critical role for macrophages in supporting the extensive vascular network required for corpus luteum integrity and production of progesterone essential for establishing pregnancy. Our findings raise the prospect that disruption of macrophage-endothelial cell interactions underpinning corpus luteum development contributes to infertility in women in whom luteal insufficiency is implicated. PMID:23867505

  7. The history of nephrology in the Talmudic corpus.

    PubMed

    Dvorjetski, Estée

    2002-07-01

    The kidneys, the bladder and nephrology in general were discussed in the Talmudic literature from their anatomical, pathological and philological aspects. The Sages' deliberations were based on the Biblical texts. The characteristic phraseology of the scriptures uses the kidneys as symbols of the human emotions, contrary to the heart, which is regarded as the location of wisdom. The kidney is considered to be the individual's seat of their deepest desires--perhaps because it is an "internal" organ, well hidden, surrounded by a capsule and by a layer of perinephric fat. The Talmudic corpus considers the kidneys to be the origin of secret counsels--"the kidneys advise". An injury to the kidneys is used symbolically as an example of a cruel and serious injury. The sages were concerned with nephrological problems such as a diseased kidney of small size, fluid and pus in the kidney, injuries, perforations and more. Fascinating advice is given regarding micturition, its timing, characteristics and significance. The Halakhah is concerned with the kidneys during the examination of an animal after slaughter for the fitness for its ritual consumption. The paper presents various nephrological diseases from the Talmudic corpus. Among them are, for example, "Tzemirtha"--urolithiasis; "Hydrakon"--hydronephrosis; "Suskhinta"--urinary retention; "Tzinit"--podagra, gout, and "Yerakon"--icterus. A survey of some Talmudic personalities will exemplify the existence of these conditions. PMID:12097728

  8. Interpretations of the Healer's Touch in the Hippocratic Corpus.

    PubMed

    Kosak, Jennifer

    2016-01-01

    This paper analyses gender as an aspect of the role of touch in the relationship between doctors and patients, as represented in the Hippocratic Corpus. Touch is an essential aspect of the ancient doctor's art, but one potentially fraught with concerns over gender: while seeing, hearing, and smelling are also central to the medical encounter, touching is the act that places the greatest demands on the privacy and bodily integrity of the patient. This paper shows--perhaps counterintuitively--that, despite the multiple assertions of gender differences put forward by the authors of the Hippocratic Corpus, these authors make little distinction between touching male and female patients. At the same time, the paper argues that ancient physicians were anxious to avoid the charge that they were harming their patients when they touched them. It demonstrates that male doctors, sensitive as they were to the problems posed by their interactions with female patients, were challenged in different ways when engaging in intimate contact with male patients. PMID:26946680

  9. Distractor Dwelling, Skipping, and Revisiting Determine Target Absent Performance in Difficult Visual Search.

    PubMed

    Horstmann, Gernot; Herwig, Arvid; Becker, Stefanie I

    2016-01-01

    Some targets in visual search are more difficult to find than others. In particular, a target that is similar to the distractors is more difficult to find than a target that is dissimilar to the distractors. Efficiency differences between easy and difficult searches are manifest not only in target-present trials but also in target-absent trials. In fact, even physically identical displays are searched through with different efficiency depending on the searched-for target. Here, we monitored eye movements in search for a target similar to the distractors (difficult search) versus a target dissimilar to the distractors (easy search). We aimed to examine three hypotheses concerning the causes of differential search efficiencies in target-absent trials: (a) distractor dwelling (b) distractor skipping, and (c) distractor revisiting. Reaction times increased with target similarity which is consistent with existing theories and replicates earlier results. Eye movement data indicated guidance in target trials, even though search was very slow. Dwelling, skipping, and revisiting contributed to low search efficiency in difficult search, with dwelling being the strongest factor. It is argued that differences in dwell time account for a large amount of total search time differences. PMID:27574510

  10. Distractor Dwelling, Skipping, and Revisiting Determine Target Absent Performance in Difficult Visual Search

    PubMed Central

    Horstmann, Gernot; Herwig, Arvid; Becker, Stefanie I.

    2016-01-01

    Some targets in visual search are more difficult to find than others. In particular, a target that is similar to the distractors is more difficult to find than a target that is dissimilar to the distractors. Efficiency differences between easy and difficult searches are manifest not only in target-present trials but also in target-absent trials. In fact, even physically identical displays are searched through with different efficiency depending on the searched-for target. Here, we monitored eye movements in search for a target similar to the distractors (difficult search) versus a target dissimilar to the distractors (easy search). We aimed to examine three hypotheses concerning the causes of differential search efficiencies in target-absent trials: (a) distractor dwelling (b) distractor skipping, and (c) distractor revisiting. Reaction times increased with target similarity which is consistent with existing theories and replicates earlier results. Eye movement data indicated guidance in target trials, even though search was very slow. Dwelling, skipping, and revisiting contributed to low search efficiency in difficult search, with dwelling being the strongest factor. It is argued that differences in dwell time account for a large amount of total search time differences. PMID:27574510

  11. Mourning the dead, mourning the disappeared: the enigma of the absent-presence.

    PubMed

    Taiana, Cecilia

    2014-12-01

    Freud's interest in the impact of death on the living goes back further than Mourning and Melancholia (1917e, [1915]). In Totem and Taboo (1912-13) Freud noted the ambivalence of the emotions we experience in relation to the dead. In this paper, I focus on Mourning and Melancholia as a landmark in the understanding of both the normal and psychopathological aspects of mourning and depressive processes in human beings. Mourning and Melancholia bridges Freud's first and second topographic theories of the psychic apparatus and constitutes for many authors the foundation of his theory of internal object relations. With this psychoanalytic understanding of mourning as a framework, I discuss 'special mourning processes,' such as the those confronted by psychoanalysts in Argentina when treating the relatives of thousands of people who were 'disappeared' by the military dictatorship in the 1970s; they are 'special' in the sense that the external reality [which] constitutes the starting point of the psychic mourning process, as described by Freud, is absent. I argue that the 'absent-presence' of the body as an enigmatic message initiates a special mourning process that bears certain characteristics of, and is isomorphic to, Laplanche's seduction theory. PMID:25363451

  12. Group velocity mismatch-absent nonlinear frequency conversions for mid-infrared femtosecond pulses generation

    PubMed Central

    Zhong, Haizhe; Zhang, Lifu; Li, Ying; Fan, Dianyuan

    2015-01-01

    A novel group velocity mismatch (GVM) absent scheme for nonlinear optical parametric procedure in mid-infrared was developed with type-I quasi phase matching by use of an off-digital nonlinear optical coefficient d31. This was achieved by matching of the group velocities of the pump and the signal waves, while the phase velocities were quasi phase matched. The system employs MgO-doped periodically poled LiNbO3 as the nonlinear medium. Desired group-velocity dispersion would be obtained via appropriately temperature regulation. To demonstrate its potential applications in ultrafast mid-infrared pulses generation, aiming at a typical mid-infrared wavelength of ~3.2 μm, design examples of two basic nonlinear frequency conversion procedures are studied for both the narrow-band seeding mid-IR optical parametric amplification (OPA) and the synchronously pumped femtosecond optical parametric oscillation (SPOPO). Compared with the conventional scheme of type-0 QPM, the quantum-efficiency can be more than doubled with nearly unlimited bandwidth. The proposed GVM- absent phase matching design may provide a promising route to efficient and broadband sub-100 fs mid-infrared ultrafast pulses generation without group-velocity walk-off. PMID:26099837

  13. The Use of Corpus Concordancing for Second Language Learners' Self Error-Correction

    ERIC Educational Resources Information Center

    Feng, Hui-Hsien

    2014-01-01

    Corpus concordancing has been utilized in second language (L2) writing classrooms for a few decades. Some studies have shown that this application is helpful, to a certain degree, to learners' writing process. However, how corpus concordancing is utilized for nonnative speakers' (NNSs) self error-correction in writing, especially the…

  14. Formulaic Language in Native and Second Language Speakers: Psycholinguistics, Corpus Linguistics, and TESOL

    ERIC Educational Resources Information Center

    Ellis, Nick C.; Simpson-Vlach, Rita; Maynard, Carson

    2008-01-01

    Natural language makes considerable use of recurrent formulaic patterns of words. This article triangulates the construct of "formula" from corpus linguistic, psycholinguistic, and educational perspectives. It describes the corpus linguistic extraction of pedagogically useful formulaic sequences for academic speech and writing. It determines…

  15. A Corpus-Based Approach to Online Materials Development for Writing Research Articles

    ERIC Educational Resources Information Center

    Chang, Ching-Fen; Kuo, Chih-Hua

    2011-01-01

    There has been increasing interest in the possible applications of corpora to both linguistic research and pedagogy. This study takes a corpus-based, genre-analytic approach to discipline-specific materials development. Combining corpus analysis with genre analysis makes it possible to develop teaching materials that are not only authentic but…

  16. Verb-Noun Collocations in Second Language Writing: A Corpus Analysis of Learners' English

    ERIC Educational Resources Information Center

    Laufer, Batia; Waldman, Tina

    2011-01-01

    The present study investigates the use of English verb-noun collocations in the writing of native speakers of Hebrew at three proficiency levels. For this purpose, we compiled a learner corpus that consists of about 300,000 words of argumentative and descriptive essays. For comparison purposes, we selected LOCNESS, a corpus of young adult native…

  17. A Corpus-Based View of Lexical Gender in Written Business English

    ERIC Educational Resources Information Center

    Fuertes-Olivera, Pedro A.

    2007-01-01

    This article investigates lexical gender in specialized communication. The key method of analysis is that of forms of address, professional titles, and "generic man" in a 10 million word corpus of written Business English. After a brief introduction and literature review on both gender in specialized communication and similar corpus-based views of…

  18. Attitudes towards English in Norway: A Corpus-Based Study of Attitudinal Expressions in Newspaper Discourse

    ERIC Educational Resources Information Center

    Graedler, Anne-Line

    2014-01-01

    This article explores some dimensions of how the role of the English language in Norway has been discursively constructed in newspapers during recent years, based on the analysis of data from the five-year period 2008-2012. The analysis is conducted using a specialised corpus containing 3,743 newspaper articles which were subjected to corpus-based…

  19. Using Edit Distance to Analyse Errors in a Natural Language to Logic Translation Corpus

    ERIC Educational Resources Information Center

    Barker-Plummer, Dave; Dale, Robert; Cox, Richard; Romanczuk, Alex

    2012-01-01

    We have assembled a large corpus of student submissions to an automatic grading system, where the subject matter involves the translation of natural language sentences into propositional logic. Of the 2.3 million translation instances in the corpus, 286,000 (approximately 12%) are categorized as being in error. We want to understand the nature of…

  20. Capturing L2 Accuracy Developmental Patterns: Insights from an Error-Tagged EFL Learner Corpus

    ERIC Educational Resources Information Center

    Thewissen, Jennifer

    2013-01-01

    The present article addresses the issue of second language accuracy developmental trajectories and shows how they can be captured via an error-tagged version of an English as a Foreign Language (EFL) learner corpus. The data used in this study were extracted from the International Corpus of Learner English (Granger et al., 2009) and consist of a…

  1. English Collocation Learning through Corpus Data: On-Line Concordance and Statistical Information

    ERIC Educational Resources Information Center

    Ohtake, Hiroshi; Fujita, Nobuyuki; Kawamoto, Takeshi; Morren, Brian; Ugawa, Yoshihiro; Kaneko, Shuji

    2012-01-01

    We developed an English Collocations On Demand system offering on-line corpus and concordance information to help Japanese researchers acquire a better command of English collocation patterns. The Life Science Dictionary Corpus consists of approximately 90,000,000 words collected from life science related research papers published in academic…

  2. More than a Linguistic Reference: The Infuence of Corpus Technology on L2 Academic Writing

    ERIC Educational Resources Information Center

    Yoon, Hyunsook

    2008-01-01

    This paper reports on a qualitative study that investigated the changes in students' writing process associated with corpus use over an extended period of time. The primary purpose of this study was to examine how corpus technology affects students' development of competence as second language (L2) writers. The research was mainly based on case…

  3. An Empirical Study on Corpus-Driven English Vocabulary Learning in China

    ERIC Educational Resources Information Center

    Binkai, Jiao

    2012-01-01

    This paper focuses on the autonomous English vocabulary learning in corpus-based contexts. Language teaching practice is becoming more learner-centered in the field of language teaching, learner autonomy has been an ongoing concern of foreign language educators in china. As an assistant tool in language learning, corpus makes an easy and quick…

  4. Lexical Properties of Slovene Sign Language: A Corpus-Based Study

    ERIC Educational Resources Information Center

    Vintar, Špela

    2015-01-01

    Slovene Sign Language (SZJ) has as yet received little attention from linguists. This article presents some basic facts about SZJ, its history, current status, and a description of the Slovene Sign Language Corpus and Pilot Grammar (SIGNOR) project, which compiled and annotated a representative corpus of SZJ. Finally, selected quantitative data…

  5. A Quantitative Corpus-Based Approach to English Spatial Particles: Conceptual Symmetry and Its Pedagogical Implications

    ERIC Educational Resources Information Center

    Chen, Alvin Cheng-Hsien

    2014-01-01

    The present study aims to investigate how conceptual symmetry plays a role in the use of spatial particles in English and to further examine its pedagogical implications via a corpus-based evaluation of the course books in senior high schools in Taiwan. More specifically, we adopt a quantitative corpus-based approach to investigate whether bipolar…

  6. Productive Vocabulary Knowledge and Evaluation of ESL Writing in Corpus-Based Language Learning

    ERIC Educational Resources Information Center

    Nam, Daehyeon

    2010-01-01

    Since Sinclair (1991) concretized the possibilities of processing and analyzing large quantities of text data through corpus linguistic techniques, the applications of corpus linguistic approaches employing authentic language data and empirical evidence have been widely accepted in language teaching and research. As the applications of corpus…

  7. Language with Character: A Stratified Corpus Comparison of Individual Differences in E-Mail Communication

    ERIC Educational Resources Information Center

    Oberlander, Jon; Gill, Alastair J.

    2006-01-01

    To what extent does the wording and syntactic form of people's writing reflect their personalities? Using a bottom-up stratified corpus comparison, rather than the top-down content analysis techniques that have been used before, we examine a corpus of e-mail messages elicited from individuals of known personality, as measured by the Eysenck…

  8. Applying Corpus-Based Findings to Form-Focused Instruction: The Case of Reported Speech

    ERIC Educational Resources Information Center

    Barbieri, Federica; Eckhardt, Suzanne E. B.

    2007-01-01

    Arguing that the introduction of corpus linguistics in teaching materials and the language classroom should be informed by theories and principles of SLA, this paper presents a case study illustrating how corpus-based findings on reported speech can be integrated into a form-focused model of instruction. After overviewing previous work which…

  9. A Corpus-Based Discourse Analysis of the Vision and Mission Statements of Universities in Turkey

    ERIC Educational Resources Information Center

    Efe, Ibrahim; Ozer, Omer

    2015-01-01

    This article presents findings from a corpus-assisted discourse analysis of mission and vision statements of 105 state and 66 private/foundation universities in Turkey. The paper combines a corpus-based approach with critical discourse analysis to interpret the data in relation to its institutional as well as socio-political context. It argues…

  10. "Nice Things Get Said": Corpus Evidence and the National Literacy Strategy

    ERIC Educational Resources Information Center

    Sealey, Alison; Thompson, Paul

    2006-01-01

    The article compares evidence from an electronic corpus of texts written for a child audience with specifications in the National Literacy Strategy. The concepts and terminology associated with corpus linguistics are introduced and explained, and the research study from which the findings derive is summarised. Results of the analysis are presented…

  11. Identification of Myotropic Neuropeptides from the Brain and Corpus Cardiacum-Corpus Allatum Complex of the Beetle, Zophobas atratus

    PubMed Central

    Marciniak, Pawel; Audsley, Neil; Kuczer, Mariola; Rosinski, Grzegorz

    2010-01-01

    The neuropeptide profiles of the two major neuro-endocrinological organs, brain and retrocerebral complex corpus cardiacum-corpus allatum (CC/CA) of adult beetles, Zophobas atratus Fabricius (Coleoptera:Tenebrionidae) were analyzed by a combination of high performance liquid chromatography (HPLC) and matrix-assisted laser desorption ionization time of flight tandem mass spectrometry (MALDI TOF/TOF MS). The homological semi-isolated heart bioassay was used to screen HPLC fractions for myotropic activity in tissues, revealing several cardiostimulatory and cardioinhibitory factors from both the brain and CC/CA. Analysis of HPLC fractions by MALDI-TOF MS identified seven mass ions that could be assigned to other known peptides: leucomyosuppressin (LMS), Tribolium castaneum pyrokinin 2, sulfakinin 1, myoinhibitory peptide 4, a truncated NVP-like peptide, Tenebrio molitor AKH and crustacean cardioactive peptide. In addition, two novel peptides, myosuppressin (pEDVEHVFLRFa), which differs from LMS by one amino acid (E for D at position 4) and pyrokinin-like peptide (LPHYTPRLa) were also identified. To establish cardioactive properties of some of the identified peptides, chemical synthesis was carried out and their activities were tested using the heart bioassay. PMID:21067424

  12. Identification of myotropic neuropeptides from the brain and corpus cardiacum-corpus allatum complex of the beetle, Zophobas atratus.

    PubMed

    Marciniak, Pawel; Audsley, Neil; Kuczer, Mariola; Rosinski, Grzegorz

    2010-01-01

    The neuropeptide profiles of the two major neuro-endocrinological organs, brain and retrocerebral complex corpus cardiacum-corpus allatum (CC/CA) of adult beetles, Zophobas atratus Fabricius (Coleoptera:Tenebrionidae) were analyzed by a combination of high performance liquid chromatography (HPLC) and matrix-assisted laser desorption ionization time of flight tandem mass spectrometry (MALDI TOF/TOF MS). The homological semi-isolated heart bioassay was used to screen HPLC fractions for myotropic activity in tissues, revealing several cardiostimulatory and cardioinhibitory factors from both the brain and CC/CA. Analysis of HPLC fractions by MALDI-TOF MS identified seven mass ions that could be assigned to other known peptides: leucomyosuppressin (LMS), Tribolium castaneum pyrokinin 2, sulfakinin 1, myoinhibitory peptide 4, a truncated NVP-like peptide, Tenebrio molitor AKH and crustacean cardioactive peptide. In addition, two novel peptides, myosuppressin (pEDVEHVFLRFa), which differs from LMS by one amino acid (E for D at position 4) and pyrokinin-like peptide (LPHYTPRLa) were also identified. To establish cardioactive properties of some of the identified peptides, chemical synthesis was carried out and their activities were tested using the heart bioassay. PMID:21067424

  13. Corpus-based Approach to Creating a Semantic Lexicon for Clinical Research Eligibility Criteria from UMLS

    PubMed Central

    Luo, Zhihui; Duffy, Robert; Johnson, Stephen; Weng, Chunhua

    2010-01-01

    We describe a corpus-based approach to creating a semantic lexicon using UMLS knowledge sources. We extracted 10,000 sentences from the eligibility criteria sections of clinical trial summaries contained in ClinicalTrials.gov. The UMLS Metathesaurus and SPECIALIST Lexical Tools were used to extract and normalize UMLS recognizable terms. When annotated with Semantic Network types, the corpus had a lexical ambiguity of 1.57 (=total types for unique lexemes / total unique lexemes) and a word occurrence ambiguity of 1.96 (=total type occurrences / total word occurrences). A set of semantic preference rules was developed and applied to completely eliminate ambiguity in semantic type assignment. The lexicon covered 95.95% UMLS-recognizable terms in our corpus. A total of 20 UMLS semantic types, representing about 17% of all the distinct semantic types assigned to corpus lexemes, covered about 80% of the vocabulary of our corpus. PMID:21347142

  14. EYA4, a novel vertebrate gene related to Drosophila eyes absent.

    PubMed

    Borsani, G; DeGrandi, A; Ballabio, A; Bulfone, A; Bernard, L; Banfi, S; Gattuso, C; Mariani, M; Dixon, M; Donnai, D; Metcalfe, K; Winter, R; Robertson, M; Axton, R; Brown, A; van Heyningen, V; Hanson, I

    1999-01-01

    We have isolated a family of four vertebrate genes homologous to eyes absent (eya), a key regulator of ocular development in Drosophila. Here we present the detailed characterization of the EYA4 gene in human and mouse. EYA4 encodes a 640 amino acid protein containing a highly conserved C-terminal domain of 271 amino acids which in Drosophila eya is known to mediate developmentally important protein-protein interactions. Human EYA4 maps to 6q23 and mouse Eya4 maps to the predicted homology region near the centromere of chromosome 10. In the developing mouse embryo, Eya4 is expressed primarily in the craniofacial mesenchyme, the dermamyotome and the limb. On the basis of map position and expression pattern, EYA4 is a candidate for oculo-dento-digital (ODD) syndrome, but no EYA4 mutations were found in a panel of ODD patients. PMID:9887327

  15. Characterization of the threonine-phosphatase of mouse eyes absent 3.

    PubMed

    Sano, Teruyuki; Nagata, Shigekazu

    2011-09-01

    Eyes absent (EYA) has tyrosine- and threonine-phosphatase activities in their C-terminal and N-terminal regions, respectively. Using various mutants of mouse EYA3, we showed that the 68-amino acid domain between positions 53 and 120 was necessary and sufficient for its threonine-phosphatase activity. Point mutations were then introduced, and residues Cys-56, Tyr-77, His-79, and Tyr-90 were essential for the EYA3s threonine-phosphatase. The 68-amino acid domain is not well conserved among the four mouse EYA members, but is evolutionally highly conserved in the orthologous EYA members of different species, suggesting that the threonine-phosphatase of EYA3 has a function distinct from that of the other EYAs. PMID:21821028

  16. Invasive sinonasal adenocarcinoma with an absent olfactory bulb: a case report.

    PubMed

    Newman, Thomas H; Tipper, Geoffrey A; Hussain, Zakier

    2016-01-01

    Sinonasal adenocarcinomas are rare, locally invasive tumours. In this case the symptomatic profile was unusual and the diagnosis was missed at the primary care stage. Interestingly this would be the first documented case with an absent ipsilateral olfactory bulb. A 55-year old male presented with symptoms of behavioural change and mild headaches. He was later found to have a large Sinonasal adenocarcinoma which penetrated the skull base. This was treated by a combined craniotomy and endonasal approach. Sinonasal adenocarcinomas are unusual tumours and further research is required in order to clarify management strategies and prognosis. This interesting case was more unusual again given its presentation, extent and absence of the olfactory bulb. Importantly for primary care physicians the initial diagnosis was considered psychiatric rather than organic; despite there being specific features of the presentation which were suggestive of an intra-cranial lesion. PMID:27402540

  17. Invasive sinonasal adenocarcinoma with an absent olfactory bulb: a case report

    PubMed Central

    Newman, Thomas H.; Tipper, Geoffrey A.; Hussain, Zakier

    2016-01-01

    Sinonasal adenocarcinomas are rare, locally invasive tumours. In this case the symptomatic profile was unusual and the diagnosis was missed at the primary care stage. Interestingly this would be the first documented case with an absent ipsilateral olfactory bulb. A 55-year old male presented with symptoms of behavioural change and mild headaches. He was later found to have a large Sinonasal adenocarcinoma which penetrated the skull base. This was treated by a combined craniotomy and endonasal approach. Sinonasal adenocarcinomas are unusual tumours and further research is required in order to clarify management strategies and prognosis. This interesting case was more unusual again given its presentation, extent and absence of the olfactory bulb. Importantly for primary care physicians the initial diagnosis was considered psychiatric rather than organic; despite there being specific features of the presentation which were suggestive of an intra-cranial lesion. PMID:27402540

  18. Computerized axial tomography of the chest for visualization of ''absent'' pulmonary arteries

    SciTech Connect

    Sondheimer, H.M.; Oliphant, M.; Schneider, B.; Kavey, R.E.W.; Blackman, M.S.; Parker, F.B. Jr.

    1982-05-01

    To expand the search for central pulmonary arteries in six patients with absence of cardiac-pulmonary continuity, computerized axial tomography (CAT) of the chest was performed. The CAT scans were compared with previous arteriograms and pulmonary vein wedge angiograms. Three patients with type IV truncus arteriosus were studied, and none had a central, right or left pulmonary artery on CAT scan. However, two patients with tetralogy of Fallot with pulmonary atresia and a patent ductus arteriosus to the right lung demonstrated the presence of a left pulmonary artery. In addition, one child with truncus arteriosus with ''absent'' left pulmonary artery demonstrated a left pulmonary artery on the CAT scan. The CAT scan may therefore enhance our ability to search for disconnected pulmonary arteries in children with complex cyanotic congenital heart disease.

  19. The post-syrinx syndrome: stable central myelopathy and collapsed or absent syrinx.

    PubMed

    Bogdanov, E I; Heiss, John D; Mendelevich, E G

    2006-06-01

    Among 168 cases with neurologic findings of cervicothoracic syringomyelia and MRI findings of Chiari 1 malformation and/or underdevelopment of the posterior cranial fossa, 15 patients (9.1 %) had collapsed, flat syrinxes and 14 patients (8.3 %) did not have syrinxes. Both groups of patients had clinical findings of central myelopathy that had been stable for at least 3 years. Magnetic resonance imaging detected atrophy of the cervical spinal cord in both groups and spontaneous communications between the syrinx and the subarachnoid space in 3 patients of the group with collapsed syrinxes. Analysis of these results and review of the literature suggest that patients with clinical signs of syringomyelia and Chiari 1 malformation or underdeveloped posterior fossa, but with small or absent syringomyelitic cavities, have the "postsyrinx" state as a result of spontaneous collapse of distended syrinxes. PMID:16511636

  20. The Wildcat Corpus of Native- and Foreign-Accented English: Communicative Efficiency across Conversational Dyads with Varying Language Alignment Profiles

    ERIC Educational Resources Information Center

    Van Engen, Kristin J.; Baese-Berk, Melissa; Baker, Rachel E.; Choi, Arim; Kim, Midam; Bradlow, Ann R.

    2010-01-01

    This paper describes the development of the Wildcat Corpus of native- and foreign-accented English, a corpus containing scripted and spontaneous speech recordings from 24 native speakers of American English and 52 non-native speakers of English. The core element of this corpus is a set of spontaneous speech recordings, for which a new method of…

  1. An Analysis of the Application of Wikipedia Corpus on the Lexical Learning in the Second Language Acquisition

    ERIC Educational Resources Information Center

    Shi, Jing

    2015-01-01

    Corpus linguistics has transformed linguistic research but has a slightly moderate impact on the ESL teaching and learning. The Wikipedia Corpus, designed by Mark Davis is introduced in this essay. The corpus allows teachers to search Wikipedia in a powerful way: they can search by word, phrase, part of speech, and synonyms. Teachers can also find…

  2. Multimodal imaging of subventricular zone neural stem/progenitor cells in the cuprizone mouse model reveals increased neurogenic potential for the olfactory bulb pathway, but no contribution to remyelination of the corpus callosum.

    PubMed

    Guglielmetti, Caroline; Praet, Jelle; Rangarajan, Janaki Raman; Vreys, Ruth; De Vocht, Nathalie; Maes, Frederik; Verhoye, Marleen; Ponsaerts, Peter; Van der Linden, Annemie

    2014-02-01

    Multiple sclerosis is a devastating demyelinating disease of the central nervous system (CNS) in which endogenous remyelination, and thus recovery, often fails. Although the cuprizone mouse model allowed elucidation of many molecular factors governing remyelination, currently very little is known about the spatial origin of the oligodendrocyte progenitor cells that initiate remyelination in this model. Therefore, we here investigated in this model whether subventricular zone (SVZ) neural stem/progenitor cells (NSPCs) contribute to remyelination of the splenium following cuprizone-induced demyelination. Experimentally, from the day of in situ NSPC labeling, C57BL/6J mice were fed a 0.2% cuprizone diet during a 4-week period and then left to recover on a normal diet for 8weeks. Two in situ labeling strategies were employed: (i) NSPCs were labeled by intraventricular injection of micron-sized iron oxide particles and then followed up longitudinally by means of magnetic resonance imaging (MRI), and (ii) SVZ NSPCs were transduced with a lentiviral vector encoding the eGFP and Luciferase reporter proteins for longitudinal monitoring by means of in vivo bioluminescence imaging (BLI). In contrast to preceding suggestions, no migration of SVZ NSPC towards the demyelinated splenium was observed using both MRI and BLI, and further validated by histological analysis, thereby demonstrating that SVZ NSPCs are unable to contribute directly to remyelination of the splenium in the cuprizone model. Interestingly, using longitudinal BLI analysis and confirmed by histological analysis, an increased migration of SVZ NSPC-derived neuroblasts towards the olfactory bulb was observed following cuprizone treatment, indicative for a potential link between CNS inflammation and increased neurogenesis. PMID:23933305

  3. Proximal hypospadias with skin-covered shaft of penis and absent urethral plate: An unknown variant and its management

    PubMed Central

    Rashid, Kumar A.; Bhat, Nisar A.

    2011-01-01

    We report a case of proximal hypospadias with an absent urethral plate having intact ventral shaft skin with hooded dorsal prepuce and a good glans groove. Such a variant of hypospadias has not been reported in the literature. PMID:22121320

  4. Silent dropouts in health surveys: are nonrespondent absent teenagers different from those who participate in school-based health surveys?

    PubMed

    Michaud, P A; Delbos-Piot, I; Narring, F

    1998-04-01

    3324 in-school students aged 15-20 years randomly selected from high schools and professional centers in francophone Switzerland answered a self-administered questionnaire about their health problems, needs, and behavior. Their responses were compared with those of 96 absent students sampled via telephone on a shorter, but similar questionnaire. Relative to the absent students, a significantly higher percentage of in-school students reported skin problems, weight concerns, sleep problems, headaches, stomach aches, and vision or dental problems. The percentages of students reporting a need for help were also higher among present students than among those who were absent: nutrition, 21.8 vs. 9.4; stress, 44.2 vs. 31.3; depression, 28.4 vs. 18.9; sleep problems, 21.3 vs. 12.1; sports, 9.2 vs. 4.2; and love life, 31.5 vs. 14.5. The rates of hospitalization and injuries were lower among absent students, 28.2 vs. 40.1. A higher proportion of absent students were sexually active and they also had a tendency to use tobacco, alcohol, and cannabis more often than did present students. Absent students also more frequently partook of leisure and group activities. Study findings suggest that within the Swiss context, school absenteeism is probably related less to physical or chronic health problems than to hedonistic lifestyles which predispose some students skip part of the school hours. PMID:9561465

  5. BioInfer: a corpus for information extraction in the biomedical domain

    PubMed Central

    Pyysalo, Sampo; Ginter, Filip; Heimonen, Juho; Björne, Jari; Boberg, Jorma; Järvinen, Jouni; Salakoski, Tapio

    2007-01-01

    Background Lately, there has been a great interest in the application of information extraction methods to the biomedical domain, in particular, to the extraction of relationships of genes, proteins, and RNA from scientific publications. The development and evaluation of such methods requires annotated domain corpora. Results We present BioInfer (Bio Information Extraction Resource), a new public resource providing an annotated corpus of biomedical English. We describe an annotation scheme capturing named entities and their relationships along with a dependency analysis of sentence syntax. We further present ontologies defining the types of entities and relationships annotated in the corpus. Currently, the corpus contains 1100 sentences from abstracts of biomedical research articles annotated for relationships, named entities, as well as syntactic dependencies. Supporting software is provided with the corpus. The corpus is unique in the domain in combining these annotation types for a single set of sentences, and in the level of detail of the relationship annotation. Conclusion We introduce a corpus targeted at protein, gene, and RNA relationships which serves as a resource for the development of information extraction systems and their components such as parsers and domain analyzers. The corpus will be maintained and further developed with a current version being available at . PMID:17291334

  6. A human vocal utterance corpus for perceptual and acoustic analysis of speech, singing, and intermediate vocalizations

    NASA Astrophysics Data System (ADS)

    Gerhard, David

    2002-11-01

    In this paper we present the collection and annotation process of a corpus of human utterance vocalizations used for speech and song research. The corpus was collected to fill a void in current research tools, since no corpus currently exists which is useful for the classification of intermediate utterances between speech and monophonic singing. Much work has been done in the domain of speech versus music discrimination, and several corpora exist which can be used for this research. A specific example is the work done by Eric Scheirer and Malcom Slaney [IEEE ICASSP, 1997, pp. 1331-1334]. The collection of the corpus is described including questionnaire design and intended and actual response characteristics, as well as the collection and annotation of pre-existing samples. The annotation of the corpus consisted of a survey tool for a subset of the corpus samples, including ratings of the clips based on a speech-song continuum, and questions on the perceptual qualities of speech and song, both generally and corresponding to particular clips in the corpus.

  7. A method for determining the number of documents needed for a gold standard corpus.

    PubMed

    Juckett, David

    2012-06-01

    The unstructured narratives in medicine have been increasingly targeted for content extraction using the techniques of natural language processing (NLP). In most cases, these efforts are facilitated by creating a manually annotated set of narratives containing the ground truth; commonly referred to as a gold standard corpus. This corpus is used for modeling, fine-tuning, and testing NLP software as well as providing the basis for training in machine learning. Determining the number of annotated documents (size) for this corpus is important, but rarely described; rather, the factors of cost and time appear to dominate decision-making about corpus size. In this report, a method is outlined to determine gold standard size based on the capture probabilities for the unique words within a target corpus. To demonstrate this method, a corpus of dictation letters from the Michigan Pain Consultant (MPC) clinics for pain management are described and analyzed. A well-formed working corpus of 10,000 dictations was first constructed to provide a representative subset of the total, with no more than one dictation letter per patient. Each dictation was divided into words and common words were removed. The Poisson function was used to determine probabilities of word capture within samples taken from the working corpus, and then integrated over word length to give a single capture probability as a function of sample size. For these MPC dictations, a sample size of 500 documents is predicted to give a capture probability of approximately 0.95. Continuing the demonstration of sample selection, a provisional gold standard corpus of 500 documents was selected and examined for its similarity to the MPC structured coding and demographic data available for each patient. It is shown that a representative sample, of justifiable size, can be selected for use as a gold standard. PMID:22245601

  8. The catalogue of the Ripley Corpus: alchemical writings attributed to George Ripley (d. ca. 1490).

    PubMed

    Rampling, Jennifer M

    2010-07-01

    The period 1471 to 1700 saw the accretion of a large corpus of alchemical works associated with the famous English alchemist George Ripley, Canon of Bridlington (d. ca. 1490). Evaluation of Ripley's alchemy is hampered by uncertainty over the composition of the corpus, the dating and provenance of individual texts, and the difficulty of separating genuine from spurious attributions. The Catalogue of the Ripley Corpus (CRC) provides a first step in ordering these diverse materials: a descriptive catalogue of approximately forty-five alchemical treatises, recipes and poems attributed to Ripley, with an index of all known manuscript copies. PMID:20973441

  9. Preparing an Annotated Gold Standard Corpus to Share with Extramural Investigators for De-identification Research

    PubMed Central

    Deleger, Louise; Kaiser, Megan; Stoutenborough, Laura; Marsolo, Keith; Kouril, Michal; Molnar, Katalin; Solti, Imre

    2014-01-01

    Objective The current study aims to fill the gap in available healthcare de-identification resources by creating a new sharable dataset with realistic Protected Health Information (PHI) without reducing the value of the data for de-identification research. By releasing the annotated gold standard corpus with Data Use Agreement we would like to encourage other Computational Linguists to experiment with our data and develop new machine learning models for de-identification. This paper describes: (1) the modifications required by the Institutional Review Board before sharing the de-identification gold standard corpus; (2) our efforts to keep the PHI as realistic as possible; (3) and the tests to show the effectiveness of these efforts in preserving the value of the modified data set for machine learning model development. Material and Methods In a previous study we built an original de-identification gold standard corpus annotated with true Protected Health Information (PHI) from 3,503 randomly selected clinical notes for the 22 most frequent clinical note types of our institution. In the current study we modified the original gold standard corpus to make it suitable for external sharing by replacing HIPAA-specified PHI with newly generated realistic PHI. Finally, we evaluated the research value of this new dataset by comparing the performance of an existing published in-house de-identification system, when trained on the new de-identification gold standard corpus, with the performance of the same system, when trained on the original corpus. We assessed the potential benefits of using the new de-identification gold standard corpus to identify PHI in the i2b2 and PhysioNet datasets that were released by other groups for de-identification research. We also measured the effectiveness of the i2b2 and PhysioNet de-identification gold standard corpora in identifying PHI in our original clinical notes. Results Performance of the de-identification system using the new gold

  10. Unsupervised corpus distillation for represented indicator measurement on focus species detection.

    PubMed

    Wei, Chih-Hsuan; Kao, Hung-Yu

    2013-01-01

    The gene ambiguity with the highest dimension is the species with which an entity is associated in biomedical text mining. Furthermore, one of the bottlenecks in gene normalisation is focus species detection. This study presents a method which is robust for all types of articles, particularly those without explicit species mentions. Since our method requires a training corpus, we developed an iterative distillation method to extend the corpus. Unsupervised corpus is therefore helpful for the detection of focus species. In experiments, the proposed method achieved a high accuracy of 85.64% and 84.32% in datasets with and without species mentions respectively. PMID:24400519

  11. Sources and Structures of Mitotic Crossovers That Arise When BLM Helicase Is Absent in Drosophila

    PubMed Central

    LaFave, Matthew C.; Andersen, Sabrina L.; Stoffregen, Eric P.; Holsclaw, Julie K.; Kohl, Kathryn P.; Overton, Lewis J.; Sekelsky, Jeff

    2014-01-01

    The Bloom syndrome helicase, BLM, has numerous functions that prevent mitotic crossovers. We used unique features of Drosophila melanogaster to investigate origins and properties of mitotic crossovers that occur when BLM is absent. Induction of lesions that block replication forks increased crossover frequencies, consistent with functions for BLM in responding to fork blockage. In contrast, treatment with hydroxyurea, which stalls forks, did not elevate crossovers, even though mutants lacking BLM are sensitive to killing by this agent. To learn about sources of spontaneous recombination, we mapped mitotic crossovers in mutants lacking BLM. In the male germline, irradiation-induced crossovers were distributed randomly across the euchromatin, but spontaneous crossovers were nonrandom. We suggest that regions of the genome with a high frequency of mitotic crossovers may be analogous to common fragile sites in the human genome. Interestingly, in the male germline there is a paucity of crossovers in the interval that spans the pericentric heterochromatin, but in the female germline this interval is more prone to crossing over. Finally, our system allowed us to recover pairs of reciprocal crossover chromosomes. Sequencing of these revealed the existence of gene conversion tracts and did not provide any evidence for mutations associated with crossovers. These findings provide important new insights into sources and structures of mitotic crossovers and functions of BLM helicase. PMID:24172129

  12. Inhibition of Eyes Absent Homolog 4 expression induces malignant peripheral nerve sheath tumor necrosis.

    PubMed

    Miller, S J; Lan, Z D; Hardiman, A; Wu, J; Kordich, J J; Patmore, D M; Hegde, R S; Cripe, T P; Cancelas, J A; Collins, M H; Ratner, N

    2010-01-21

    Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive sarcomas without effective therapeutics. Bioinformatics was used to identify potential therapeutic targets. Paired Box (PAX), Eyes Absent (EYA), Dachsund (DACH) and Sine Oculis (SIX) genes, which form a regulatory interactive network in Drosophila, were found to be dysregulated in human MPNST cell lines and solid tumors. We identified a decrease in DACH1 expression, and increases in the expressions of PAX6, EYA1, EYA2, EYA4, and SIX1-4 genes. Consistent with the observation that half of MPNSTs develop in neurofibromatosis type 1 (NF1) patients, subsequent to NF1 mutation, we found that exogenous expression of the NF1-GTPase activating protein-related domain normalized DACH1 expression. EYA4 mRNA was elevated more than 100-fold as estimated by quantitative real-time PCR in most MPNST cell lines. In vitro, suppression of EYA4 expression using short hairpin RNA reduced cell adhesion and migration and caused cellular necrosis without affecting cell proliferation or apoptotic cell death. MPNST cells expressing shEYA4 either failed to form tumors in nude mice or formed very small tumors, with extensive necrosis but similar levels of proliferation and apoptosis as control cells. Our findings identify a role of EYA4 and possibly interacting SIX and DACH proteins in MPNSTs and suggest the EYA4 pathway as a rational therapeutic target. PMID:19901965

  13. Cloning and characterization of two vertebrate homologs of the Drosophila eyes absent gene.

    PubMed

    Zimmerman, J E; Bui, Q T; Steingrímsson, E; Nagle, D L; Fu, W; Genin, A; Spinner, N B; Copeland, N G; Jenkins, N A; Bucan, M; Bonini, N M

    1997-02-01

    The Drosophila eyes absent (eya) gene plays an essential role in the events that lead to proper development of the fly eye and embryo. Here we report the analysis of two human and two mouse homologs of the fly eya gene. Sequence comparison reveals a large domain of approximately 270 amino acids in the carboxyl terminus of the predicted mammalian proteins that shows 53% identity between the fly sequence and all of the vertebrate homologs. This Eya-homology domain is of novel sequence, with no previously identified motifs. RNA hybridization studies indicate that the mouse genes are expressed during embryogenesis and in select tissues of the adult. Both mouse Eya genes are expressed in the eye, suggesting that these genes may function in eye development in vertebrates as eya does in the fly. The mouse Eya2 gene maps to chromosome 2 in the region syntenic with human chromosome 20q13, and the mouse Eya2 gene maps to chromosome 4 in the region syntenic with human chromosome 1p36. Our findings support the notion that several families of genes (Pax-6/eyeless, Six-3/sine oculis, and Eya) play related and critical roles in the eye for both files and vertebrates. PMID:9049631

  14. A CD45 polymorphism associated with abnormal splicing is absent in African populations.

    PubMed

    Tchilian, Elma Z; Dawes, Ritu; Ramaley, Patricia A; Whitworth, James A; Yuldasheva, Nadira; Wells, R Spencer; Watera, Christine; French, Neil; Gilks, Charles F; Kunachiwa, Warunee; Ruzibakiev, Ruslan; Leetrakool, Nipapan; Carrington, Christine V F; Ramdath, D Dan; Gotch, Frances; Stephens, Henry A; Hill, Adrian V; Beverley, Peter C L

    2002-02-01

    The CD45 antigen is essential for normal antigen receptor-mediated signalling in lymphocytes, and different patterns of splicing of CD45 are associated with distinct functions in lymphocytes. Abnormal CD45 splicing has been recognized in humans, caused by a C77G transversion in the gene encoding CD45 (PTPRC). Recently the C77G polymorphism has been associated with multiple sclerosis and increased susceptibility to HIV-1 infection. These studies suggest that the regulation of CD45 splicing may be critical for the proper function of the immune system. Because of these data we examined the frequency of the C77G allele in African and Asian populations from countries with high or low prevalence of HIV infection. Here we report that the variant CD45 C77G allele is absent in African populations. We further show that populations living in the Pamir mountains of Central Asia have a very high prevalence of the C77G variant. PMID:11862398

  15. Mechanosensitive enteric neurons in the guinea pig gastric corpus

    PubMed Central

    Mazzuoli-Weber, Gemma; Schemann, Michael

    2015-01-01

    For long it was believed that a particular population of enteric neurons, referred to as intrinsic primary afferent neuron (IPAN)s, encodes mechanical stimulation. We recently proposed a new concept suggesting that there are in addition mechanosensitive enteric neurons (MEN) that are multifunctional. Based on firing pattern MEN behaved as rapidly, slowly, or ultra-slowly adapting RAMEN, SAMEN, or USAMEN, respectively. We aimed to validate this concept in the myenteric plexus of the gastric corpus, a region where IPANs were not identified and existence of enteric sensory neurons was even questioned. The gastric corpus is characterized by a particularly dense extrinsic sensory innervation. Neuronal activity was recorded with voltage sensitive dye imaging after deformation of ganglia by compression (intraganglionic volume injection or von Fry hair) or tension (ganglionic stretch). We demonstrated that 27% of the gastric neurons were MEN and responded to intraganglionic volume injection. Of these 73% were RAMEN, 25% SAMEN, and 2% USAMEN with a firing frequency of 1.7 (1.1/2.2), 5.1 (2.2/7.7), and of 5.4 (5.0/15.5) Hz, respectively. The responses were reproducible and stronger with increased stimulus strength. Even after adaptation another deformation evoked spike discharge again suggesting a resetting mode of the mechanoreceptors. All MEN received fast synaptic input. Fifty five percent of all MEN were cholinergic and 45% nitrergic. Responses in some MEN significantly decreased after perfusion of TTX, low Ca++/high Mg++ Krebs solution, capsaicin induced nerve defunctionalization and capsazepine indicating the involvement of TRPV1 expressing extrinsic mechanosensitive nerves. Half of gastric MEN responded to intraganglionic volume injection as well as to ganglionic stretch and 23% responded to stretch only. Tension-sensitive MEN were to a large proportion USAMEN (44%). In summary, we demonstrated for the first time compression and tension-sensitive MEN in the stomach

  16. EFFECTS OF CORPUS CHRISTI BAY SEDIMENTS ON SURVIVAL, GROWTH AND REPRODUCTION OF THE MYSID, MYSIDOPSIS BAHIA

    EPA Science Inventory

    The study described here examined effects on mortality, growth, reproduction, and behavior of Americamysis bahi exposed under extended static conditions to bedded sediments from Corpus Christi Bay.

  17. Division of Labor in Vocabulary Structure: Insights From Corpus Analyses.

    PubMed

    Christiansen, Morten H; Monaghan, Padraic

    2016-07-01

    Psychologists have used experimental methods to study language for more than a century. However, only with the recent availability of large-scale linguistic databases has a more complete picture begun to emerge of how language is actually used, and what information is available as input to language acquisition. Analyses of such "big data" have resulted in reappraisals of key assumptions about the nature of language. As an example, we focus on corpus-based research that has shed new light on the arbitrariness of the sign: the longstanding assumption that the relationship between the sound of a word and its meaning is arbitrary. The results reveal a systematic relationship between the sound of a word and its meaning, which is stronger for early acquired words. Moreover, the analyses further uncover a systematic relationship between words and their lexical categories-nouns and verbs sound differently from each other-affecting how we learn new words and use them in sentences. Together, these results point to a division of labor between arbitrariness and systematicity in sound-meaning mappings. We conclude by arguing in favor of including "big data" analyses into the language scientist's methodological toolbox. PMID:26399384

  18. The CHEMDNER corpus of chemicals and drugs and its annotation principles

    PubMed Central

    2015-01-01

    The automatic extraction of chemical information from text requires the recognition of chemical entity mentions as one of its key steps. When developing supervised named entity recognition (NER) systems, the availability of a large, manually annotated text corpus is desirable. Furthermore, large corpora permit the robust evaluation and comparison of different approaches that detect chemicals in documents. We present the CHEMDNER corpus, a collection of 10,000 PubMed abstracts that contain a total of 84,355 chemical entity mentions labeled manually by expert chemistry literature curators, following annotation guidelines specifically defined for this task. The abstracts of the CHEMDNER corpus were selected to be representative for all major chemical disciplines. Each of the chemical entity mentions was manually labeled according to its structure-associated chemical entity mention (SACEM) class: abbreviation, family, formula, identifier, multiple, systematic and trivial. The difficulty and consistency of tagging chemicals in text was measured using an agreement study between annotators, obtaining a percentage agreement of 91. For a subset of the CHEMDNER corpus (the test set of 3,000 abstracts) we provide not only the Gold Standard manual annotations, but also mentions automatically detected by the 26 teams that participated in the BioCreative IV CHEMDNER chemical mention recognition task. In addition, we release the CHEMDNER silver standard corpus of automatically extracted mentions from 17,000 randomly selected PubMed abstracts. A version of the CHEMDNER corpus in the BioC format has been generated as well. We propose a standard for required minimum information about entity annotations for the construction of domain specific corpora on chemical and drug entities. The CHEMDNER corpus and annotation guidelines are available at: http://www.biocreative.org/resources/biocreative-iv/chemdner-corpus/ PMID:25810773

  19. The CHEMDNER corpus of chemicals and drugs and its annotation principles.

    PubMed

    Krallinger, Martin; Rabal, Obdulia; Leitner, Florian; Vazquez, Miguel; Salgado, David; Lu, Zhiyong; Leaman, Robert; Lu, Yanan; Ji, Donghong; Lowe, Daniel M; Sayle, Roger A; Batista-Navarro, Riza Theresa; Rak, Rafal; Huber, Torsten; Rocktäschel, Tim; Matos, Sérgio; Campos, David; Tang, Buzhou; Xu, Hua; Munkhdalai, Tsendsuren; Ryu, Keun Ho; Ramanan, S V; Nathan, Senthil; Žitnik, Slavko; Bajec, Marko; Weber, Lutz; Irmer, Matthias; Akhondi, Saber A; Kors, Jan A; Xu, Shuo; An, Xin; Sikdar, Utpal Kumar; Ekbal, Asif; Yoshioka, Masaharu; Dieb, Thaer M; Choi, Miji; Verspoor, Karin; Khabsa, Madian; Giles, C Lee; Liu, Hongfang; Ravikumar, Komandur Elayavilli; Lamurias, Andre; Couto, Francisco M; Dai, Hong-Jie; Tsai, Richard Tzong-Han; Ata, Caglar; Can, Tolga; Usié, Anabel; Alves, Rui; Segura-Bedmar, Isabel; Martínez, Paloma; Oyarzabal, Julen; Valencia, Alfonso

    2015-01-01

    The automatic extraction of chemical information from text requires the recognition of chemical entity mentions as one of its key steps. When developing supervised named entity recognition (NER) systems, the availability of a large, manually annotated text corpus is desirable. Furthermore, large corpora permit the robust evaluation and comparison of different approaches that detect chemicals in documents. We present the CHEMDNER corpus, a collection of 10,000 PubMed abstracts that contain a total of 84,355 chemical entity mentions labeled manually by expert chemistry literature curators, following annotation guidelines specifically defined for this task. The abstracts of the CHEMDNER corpus were selected to be representative for all major chemical disciplines. Each of the chemical entity mentions was manually labeled according to its structure-associated chemical entity mention (SACEM) class: abbreviation, family, formula, identifier, multiple, systematic and trivial. The difficulty and consistency of tagging chemicals in text was measured using an agreement study between annotators, obtaining a percentage agreement of 91. For a subset of the CHEMDNER corpus (the test set of 3,000 abstracts) we provide not only the Gold Standard manual annotations, but also mentions automatically detected by the 26 teams that participated in the BioCreative IV CHEMDNER chemical mention recognition task. In addition, we release the CHEMDNER silver standard corpus of automatically extracted mentions from 17,000 randomly selected PubMed abstracts. A version of the CHEMDNER corpus in the BioC format has been generated as well. We propose a standard for required minimum information about entity annotations for the construction of domain specific corpora on chemical and drug entities. The CHEMDNER corpus and annotation guidelines are available at: http://www.biocreative.org/resources/biocreative-iv/chemdner-corpus/. PMID:25810773

  20. Regulation of the innate immune response by threonine-phosphatase of Eyes absent.

    PubMed

    Okabe, Yasutaka; Sano, Teruyuki; Nagata, Shigekazu

    2009-07-23

    Innate immunity is stimulated not only by viral or bacterial components, but also by non-microbial danger signals (damage-associated molecular patterns). One of the damage-associated molecular patterns is chromosomal DNA that escapes degradation. In programmed cell death and erythropoiesis, DNA from dead cells or nuclei expelled from erythroblasts is digested by DNase II in the macrophages after they are engulfed. DNase II(-/-) (also known as Dnase2a(-/-)) mice suffer from severe anaemia or chronic arthritis due to interferon-beta (IFN-beta) and tumour necrosis factor-alpha (TNF-alpha) produced from the macrophages carrying undigested DNA in a Toll-like receptor (TLR)-independent mechanism. Here we show that Eyes absent 4 (EYA4), originally identified as a co-transcription factor, stimulates the expression of IFN-beta and CXCL10 in response to the undigested DNA of apoptotic cells. EYA4 enhanced the innate immune response against viruses (Newcastle disease virus and vesicular stomatitis virus), and could associate with signalling molecules (IPS-1 (also known as MAVS), STING (TMEM173) and NLRX1). Three groups have previously shown that EYA has phosphatase activity. We found that mouse EYA family members act as a phosphatase for both phosphotyrosine and phosphothreonine. The haloacid dehalogenase domain at the carboxy terminus contained the tyrosine-phosphatase, and the amino-terminal half carried the threonine-phosphatase. Mutations of the threonine-phosphatase, but not the tyrosine-phosphatase, abolished the ability of EYA4 to enhance the innate immune response, suggesting that EYA regulates the innate immune response by modulating the phosphorylation state of signal transducers for the intracellular pathogens. PMID:19561593

  1. Frequent methylation of eyes absent 4 gene in Barrett's esophagus and esophageal adenocarcinoma.

    PubMed

    Zou, Hongzhi; Osborn, Neal K; Harrington, Jonathan J; Klatt, Kristie K; Molina, Julian R; Burgart, Lawrence J; Ahlquist, David A

    2005-04-01

    Most esophageal adenocarcinomas arise within Barrett's esophagus but the cause of this increasingly prevalent condition remains unknown. Early detection improves survival and discriminant screening markers for Barrett's esophagus and cancer are needed. This study was designed to explore the natural history of eyes absent 4 (EYA4) gene methylation in the neoplastic progression of Barrett's esophagus and to evaluate methylated EYA4 as a candidate marker. Aberrant promoter methylation of EYA4 was studied by methylation-specific PCR using bisulfite-treated DNA from esophageal adenocarcinomas, Barrett's esophagus, and normal epithelia, and then confirmed by sequencing. Eight cancer cell lines were treated with the demethylation agent 5-aza-2'-deoxycytidine, and EYA4 mRNA expression with and without treatment was quantified by real-time reverse-transcription PCR. EYA4 hypermethylation was detected in 83% (33 of 40) of esophageal adenocarcinomas and 77% (27 of 35) of Barrett's tissues, but only in 3% (2 of 58) of normal esophageal and gastric mucosa samples (P < 0.001). The unmethylated cancer cell lines had much higher EYA4 mRNA expression than the methylated cancer cell lines. Demethylation caused by 5-aza-2'-deoxycytidine increased the mRNA expression level by a median of 3.2-fold in methylated cells, but its effect on unmethylated cells was negligible. Results indicate that aberrant promoter methylation of EYA4 is very common during tumorigenesis in Barrett's esophagus, occurs in early metaplasia, seems to be an important mechanism of down-regulating EYA4 expression, and represents an intriguing candidate marker for Barrett's metaplasia and esophageal cancer. PMID:15824152

  2. Late outcomes for the surgical management of absent pulmonary valve syndrome in infants

    PubMed Central

    Hu, Renjie; Zhang, Haibo; Xu, Zhiwei; Liu, Jinfen; Su, Zhaokang; Ding, Wenxiang

    2013-01-01

    OBJECTIVES Absent pulmonary valve syndrome (APVS) is a rare cardiac malformation that is usually associated with aneurysmal dilatation of pulmonary arteries and respiratory distress. The surgical mortality of neonates and infants with APVS has decreased tremendously, from 60% in 1980s to 10–20% recently. This study retrospectively reviews surgical outcomes of our 10-year experience in patients with APVS. METHODS From 2002 to 2012, 42 patients with APVS underwent surgical correction. Thirty-seven patients had APVS as a variant of tetralogy of Fallot, 4 with double outlet right ventricle and 1 with ventricular septal defect. Respiratory distress was present in 12 infants. Four patients needed continuous positive airway pressure and 5 required intubation with mechanical ventilation before surgery. RESULTS There was no hospital death and 3 late deaths. The mean follow-up time was 62.71 ± 34.31 months. Significant differences were found in the duration of postoperative ventilation between patients with or without respiratory distress (P = 0.009) and patients with left or right aortic arch (P = 0.012). The Kaplan–Meier curve indicated that overall survival at 5 and 10 years was 92.4%. The survival rates between patients with or without respiratory distress were 72.7 and 100%, respectively (P = 0.003). Overall mortality was associated with longer cardiopulmonary bypass time (P = 0.004) and lower weight at operation (P = 0.042). There were no significant differences in survival and postoperative data such as the duration of ventilation or intensive care unit stay and New York Heart Association class among the three methods of right ventricular outflow tract (RVOT) reconstruction. CONCLUSIONS Surgical treatment of APVS has got favourable outcomes in terms of mortality and reoperation rate. Different methods of RVOT reconstruction do not affect the surgical outcome. Patients required long-term follow-up for postoperative respiratory complications secondary to persistent

  3. The hydrodynamically relevant endothelial cell glycocalyx observed in vivo is absent in vitro.

    PubMed

    Potter, Daniel R; Damiano, Edward R

    2008-04-11

    In recent years, the endothelial cell surface glycocalyx has emerged as a structure of fundamental importance to a broad range of phenomena that determine cardiovascular health and disease. This new understanding of the functional significance of the glycocalyx has been made possible through recently developed experimental techniques using intravital microscopy that are capable of directly probing the glycocalyx in vivo. Using fluorescent microparticle image velocimetry in venules and endothelialized cylindrical collagen microchannels, we show that the hydrodynamically relevant endothelial cell glycocalyx surface layer observed in microvessels in vivo (0.52+/-0.28 microm thickness), which is a fundamental determinant of the hydrodynamic and mechanical environment at the endothelial cell surface, is absent from human umbilical vein (0.03+/-0.04 microm thickness) and bovine aortic (0.02+/-0.04 microm thickness) endothelial cells grown and maintained under standard cell culture conditions in vitro. An endothelial surface-bound glycosaminoglycan layer, not necessarily indicative of but having similar hydrodynamic properties to the endothelial glycocalyx observed in vivo, was detected (0.21+/-0.27 microm thickness) only after hyaluronan and chondroitin sulfate were added to the cell culture media at hyperphysiological concentrations (0.2 mg/mL perfused for 75 minutes). The implications of this glycocalyx deficiency under standard cell culture conditions in these pervasive in vitro models broadly impact a myriad of studies involving endothelial cell monolayers in which inferences are made that may depend on endothelial cell surface chemistry. In light of these findings, conclusions drawn from such studies in the areas of microvascular permeability, inflammation, mechanotransduction, and atherosclerosis must be carefully reconsidered. PMID:18258858

  4. Drosophila Eyes Absent Is Required for Normal Cone and Pigment Cell Development

    PubMed Central

    Karandikar, Umesh C.; Jin, Meng; Jusiak, Barbara; Kwak, SuJin; Chen, Rui; Mardon, Graeme

    2014-01-01

    In Drosophila, development of the compound eye is orchestrated by a network of highly conserved transcriptional regulators known as the retinal determination (RD) network. The retinal determination gene eyes absent (eya) is expressed in most cells within the developing eye field, from undifferentiated retinal progenitors to photoreceptor cells whose differentiation begins at the morphogenetic furrow (MF). Loss of eya expression leads to an early block in retinal development, making it impossible to study the role of eya expression during later steps of retinal differentiation. We have identified two new regulatory regions that control eya expression during retinal development. These two enhancers are necessary to maintain eya expression anterior to the MF (eya-IAM) and in photoreceptors (eya-PSE), respectively. We find that deleting these enhancers affects developmental events anterior to the MF as well as retinal differentiation posterior to the MF. In line with previous results, we find that reducing eya expression anterior to the MF affects several early steps during early retinal differentiation, including cell cycle arrest and expression of the proneural gene ato. Consistent with previous observations that suggest a role for eya in cell proliferation during early development we find that deletion of eya-IAM leads to a marked reduction in the size of the adult retinal field. On the other hand, deletion of eya-PSE leads to defects in cone and pigment cell development. In addition we find that eya expression is necessary to activate expression of the cone cell marker Cut and to regulate levels of the Hedgehog pathway effector Ci. In summary, our study uncovers novel aspects of eya-mediated regulation of eye development. The genetic tools generated in this study will allow for a detailed study of how the RD network regulates key steps in eye formation. PMID:25057928

  5. Supernumerary and absent limbs and digits of the lower limb: a review of the literature.

    PubMed

    Klaassen, Zachary; Shoja, Mohammadali M; Tubbs, R Shane; Loukas, Marios

    2011-07-01

    Anatomical history over centuries includes description of a wide variety of malformations involving the lower limbs. This article offers an organized review of these diverse abnormalities, including new understanding of mechanisms through recent discoveries in genetics and molecular biology. In 19th century Europe, a number of unique anomalies were reported, as well as evidence of foot amputations occurring in ancient Peruvian culture. Embryologically, the limbs develop early, with the lower limb being recognizable for the first time at stage 13 of development. By stage 23, the toes are clearly defined and by birth, although the legs appear bowed, the tibia and fibula are straight. Removal of the apical ectodermal ridge results in cessation of limb development, conversely, a second apical ectodermal ridge results in duplication of distal structures. Supernumerary limbs have been documented to occur as part of a teratoma with unique morphology and accompanying blood supply. Additionally, many examples of polydactyly occur in the foot postulating that deletion of chromosome 22q11 is involved in postaxial polydactyly. Such deletions occur near the middle of the chromosome at a location designated q11.2 (i.e., on the long arm of one of the pair of chromosomes 22) and this syndrome is also referred to as DiGeorge syndrome, which has a prevalence estimated at 1:4,000. Absence of the lower limbs has also been noted, with hypoplasia of the fibula being the most common manifestation of congenital bone absences in the lower limb. In addition to fibular aplasia, cases of tibial aplasia have been reported. This article is important for surgeons attempting correctional repair of lower limb anomalies, as well as providing analysis of the historical, anatomical and clinical aspects of supernumerary and absent limbs and digits for the lower limb. PMID:21647959

  6. Mismatch Negativity of Sad Syllables Is Absent in Patients with Major Depressive Disorder

    PubMed Central

    Pang, Xiaomei; Xu, Jing; Chang, Yi; Tang, Di; Zheng, Ya; Liu, Yanhua; Sun, Yiming

    2014-01-01

    Background Major depressive disorder (MDD) is an important and highly prevalent mental disorder characterized by anhedonia and a lack of interest in everyday activities. Additionally, patients with MDD appear to have deficits in various cognitive abilities. Although a number of studies investigating the central auditory processing of low-level sound features in patients with MDD have demonstrated that this population exhibits impairments in automatic processing, the influence of emotional voice processing has yet to be addressed. To explore the automatic processing of emotional prosodies in patients with MDD, we analyzed the ability to detect automatic changes using event-related potentials (ERPs). Method This study included 18 patients with MDD and 22 age- and sex-matched healthy controls. Subjects were instructed to watch a silent movie but to ignore the afferent acoustic emotional prosodies presented to both ears while continuous electroencephalographic activity was synchronously recorded. Prosodies included meaningless syllables, such as “dada” spoken with happy, angry, sad, or neutral tones. The mean amplitudes of the ERPs elicited by emotional stimuli and the peak latency of the emotional differential waveforms were analyzed. Results The sad MMN was absent in patients with MDD, whereas the happy and angry MMN components were similar across groups. The abnormal sad emotional MMN component was not significantly correlated with the HRSD-17 and HAMA scores, respectively. Conclusion The data indicate that patients with MDD are impaired in their ability to automatically process sad prosody, whereas their ability to process happy and angry prosodies remains normal. The dysfunctional sad emotion-related MMN in patients with MDD were not correlated with depression symptoms. The blunted MMN of sad prosodies could be considered a trait of MDD. PMID:24658084

  7. Biomechanics of cross-sectional size and shape in the hominoid mandibular corpus.

    PubMed

    Daegling, D J

    1989-09-01

    Mandibular cross sections of Pan, Pongo, Gorilla, Homo, and two fossil specimens of Paranthropus were examined by computed tomography (CT) to determine the biomechanical properties of the hominoid mandibular corpus. Images obtained by CT reveal that while the fossil hominids do not differ significantly from extant hominoids in the relative contribution of compact bone to total subperiosteal area, the shape of the Paranthropus corpora indicates that the mechanical design of the robust australopithecine mandible is fundamentally distinct from that of modern hominoids in terms of its ability to resist transverse bending and torsion. It is also apparent that, among the modern hominoids, interspecific and sexual differences in corpus shape are not significant from a biomechanical perspective. While ellipse models have been used previously to describe the size, shape, and subsequent biomechanical properties of the corpus, the present study shows that such models do not predict the biomechanical properties of corpus cross-sectional geometry in an accurate or reliable manner. The traditional "robusticity" index of the mandibular corpus is of limited utility for biomechanical interpretations. The relationship of compact bone distribution in the corpus to dimensions such as mandibular length and arch width may provide a more functionally meaningful definition of mandibular robusticity. PMID:2508480

  8. Changes in 99mTechnegas ventilation lung scan in a newborn with absent pulmonary valve syndrome.

    PubMed

    Takahashi, K; Kuwahara, T; Nagatsu, M

    2001-11-01

    A newborn infant with tetralogy of Fallot and absent pulmonary valve was successfully corrected in two stages. Absent pulmonary valve syndrome presenting in early infancy manifests severe respiratory symptoms that still make challenging both management and surgical treatment. This is ascribed to tracheobronchial compression by the extremely dilated pulmonary arteries, and to the resultant pulmonary obstructive lesions. We report herein the first findings of 99mTechnegas ventilation lung scanning in an infant with the syndrome to assess the pulmonary obstructive lesions. PMID:11813924

  9. NADPH diaphorase and nitric oxide synthase in the corpus cardiacum-corpus allatum of the cockroach Diploptera punctata.

    PubMed

    Skinner, J R; Ren, M; Chan, K K; Stay, B

    2000-01-01

    Juvenile hormone synthesis by corpora allata is regulated partly by allatostatin containing nerves from the brain that innervate the corpora cardiaca and the corpora allata. To investigate whether NO also participates in the regulation of juvenile hormone synthesis, antibody against NO synthase and the histochemical test for NADPH diaphorase activity, a marker for NO synthase, were applied to the corpora cardiaca-corpora allata of Diploptera punctata. Strong NADPH diaphorase activity occurred in corpus allatum cells but not in nerve fibers in the corpora allata or corpora cardiaca. In contrast, NO immunoreactivity occurred in nerves in the corpora cardiaca but not within the corpora allata. NO and allatostatin were not colocalized. NO synthase and NADPH diaphorase activity were localized in similar areas of the subesophageal ganglion and cells in the pars intercerebralis of the brain. Positive correlation of the quantity of NADPH diaphorase activity with juvenile hormone synthesis during the gonadotrophic cycle and lack of such correlation in subesophageal ganglia suggest that NADPH diaphorase activity reflects the necessity of NADPH in the pathway of juvenile hormone synthesis. These data suggest that NO is unlikely to play a significant role in the regulation of the corpora allata. PMID:18088916

  10. Dopamine D2 receptor bands in normal human temporal cortex are absent in Alzheimer's disease.

    PubMed

    Joyce, J N; Myers, A J; Gurevich, E

    1998-02-16

    A modular organization of bands enriched in high concentrations of D2 receptors are observed throughout the rostral to caudal aspects of the temporal cortex of the normal human at postmortem, but are most frequently observed in the inferior and superior temporal cortices [S. Goldsmith, J.N. Joyce, Dopamine D2 receptors are organized in bands in normal human temporal cortex, Neuroscience 74 (1996) 435-451]. In the tissue derived at postmortem from Alzheimer's disease cases (AD), these D2 receptor-enriched modules were found to be largely absent at rostral and mid-levels of the temporal cortex. Regions exhibiting this loss of receptor binding also showed a marked reduction in the number of pyramidal neurons stained for D2 mRNA. In addition, the AD material exhibited numerous thioflavin-positive plaques and tangle-filled extraneuronal (ghost) pyramidal neurons that were D2 mRNA-negative. Regions that are the earliest affected and most susceptible to classical AD pathology are also most sensitive to the loss of D2 receptors. These results, along with our previous data [J.N. Joyce, C. Kaeger, H. Ryoo, S. Goldsmith, Dopamine D2 receptors in the hippocampus and amygdala in Alzheimer's disease, Neurosci. Lett. 154 (1993) 171-174; H. Ryoo, J. N. Joyce, The loss of dopamine D2 receptors varies along the rostrocaudal axis of the hippocampal complex in Alzheimer's disease, J. Comp. Neurol. 348 (1994) 94-110], indicate that specific pathways enriched with D2 receptors, including that within modules of higher order association cortices of the temporal lobe and continued through segregated pathways within the parahippocampus and hippocampus, are particularly susceptible to the loss in AD. These dopamine D2 receptor-enriched modules may play an important role in the reciprocal activity of large groups of neurons in these high-order association cortical regions. Hence, the loss of the D2 receptor-enriched modules in Alzheimer's disease contributes to disturbances in information

  11. 1H–NMR Metabolomic Biomarkers of Poor Outcome after Hemorrhagic Shock are Absent in Hibernators

    PubMed Central

    Bogren, Lori K.; Murphy, Carl J.; Johnston, Erin L.; Sinha, Neeraj; Serkova, Natalie J.; Drew, Kelly L.

    2014-01-01

    rats. These same biomarkers are absent in AGS after HS with warm I/R. PMID:25211248

  12. A Combined Corpus and Systemic-Functional Analysis of the Problem-Solution Pattern in a Student and Professional Corpus of Technical Writing.

    ERIC Educational Resources Information Center

    Flowerdew, Lynne

    2003-01-01

    Reports on research describing similarities and differences between expert and novice writing in the problem-solution pattern, a frequent rhetorical pattern of technical academic writing. A corpus of undergraduate student writing and one containing professional writing consisted of 80 and 60 recommendation reports, respectively, with each corpus…

  13. Hypothyroidism prolongs corpus luteum function in the pregnant rat.

    PubMed

    Hapon, María Belén; Motta, Alicia B; Ezquer, Marcelo; Bonafede, Melisa; Jahn, Graciela A

    2007-01-01

    It has been shown that hypothyroidism in the rat produces a prolongation of pregnancy associated with a delay in the fall of circulating progesterone (P4) at term. The aim of the present work is to determine whether the delayed P4 decline in hypothyroid mother rats is due to a retarded induction of P4 degradation to 20alphaOH P4 or to a stimulation of its synthesis, and to investigate the possible mechanisms that may underlie the altered luteal function. We determined by RIA the circulating profile of the hormones (TSH, PRL, LH, P4, PGF2alpha, and PGE2) involved in luteal regulation at the end of pregnancy and, by semiquantitative RT-PCR, the expression of factors involved in P4 synthesis (CytP450scc, StAR, 3betaHSD, PRLR) and metabolism (20alphaHSD, PGF2alphaR, iNOS and COX2). Our results show that the delay in P4 decline and parturition is the resultant of retarded luteal regression, caused by a combination of decreases in luteolytic factors, mainly luteal PGF2alpha, iNOS mRNA expression and also circulating LH, and increased synthesis or action of luteotrophic factors, such as luteal and circulating PGE2 and circulating PRL. All these changes may be direct causes of the decreased 20alphaHSD mRNA and protein (measured by western blot analysis) expression, which in the presence of unchanged expression of the factors involved in P4 synthesis results in elevated luteal and circulating P4 that prolonged pregnancy and also may favor longer survival of the corpus luteum. PMID:17244746

  14. Deficits of Semantic Control Produce Absent or Reverse Frequency Effects in Comprehension: Evidence from Neuropsychology and Dual Task Methodology

    ERIC Educational Resources Information Center

    Almaghyuli, Azizah; Thompson, Hannah; Lambon Ralph, Matthew A.; Jefferies, Elizabeth

    2012-01-01

    Patients with multimodal semantic impairment following stroke (referred to here as "semantic aphasia" or SA) fail to show the standard effects of frequency in comprehension tasks. Instead, they show absent or even "reverse" frequency effects: i.e., better understanding of less common words. In addition, SA is associated with poor regulatory…

  15. 25 CFR 15.106 - May a probate case be initiated when an owner of an interest has been absent?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false May a probate case be initiated when an owner of an interest has been absent? 15.106 Section 15.106 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR PROBATE PROBATE OF INDIAN ESTATES, EXCEPT FOR MEMBERS OF THE OSAGE NATION AND THE FIVE...

  16. 25 CFR 15.106 - May a probate case be initiated when an owner of an interest has been absent?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false May a probate case be initiated when an owner of an interest has been absent? 15.106 Section 15.106 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR PROBATE PROBATE OF INDIAN ESTATES, EXCEPT FOR MEMBERS OF THE OSAGE NATION AND THE FIVE...

  17. The Concept of the Absent Curriculum: The Case of the Muslim Contribution and the English National Curriculum for History

    ERIC Educational Resources Information Center

    Wilkinson, Matthew L. N.

    2014-01-01

    This paper introduces the concept of the "absent curriculum" on the premise that the study of curriculum has been prone to privileging curricular presence to the exclusion of curricular absence. In order to address this imbalance and to articulate a theory of absence in the curriculum, the paper applies ideas derived from the philosophy…

  18. Role of different types of potassium channels in the relaxation of corpus cavernosum induced by resveratrol

    PubMed Central

    Dalaklioglu, Selvinaz; Ozbey, G.

    2014-01-01

    Background: Resveratrol (RVT), one of the most commonly employed dietary polyphenol, is used in traditional Japanese and Chinese medicine for treatment of cardiovascular diseases. Recently, we have shown that RVT has a potent relaxant effect on rat corpus cavernosum via endothelium-dependent and -independent mechanisms. Objective: The present study addressed the question whether different types of potassium channels are involved in the endothelium-dependent and -independent mechanism of corpus cavernosum relaxation induced by RVT. Materials and Methods: Strips of corpus cavernosum from rats were mounted in an organ-bath system for isometric tension studies. Results: RVT (1-100 μmol/L) produced concentration-dependent relaxation responses in rat corpus cavernosum pre-contracted by phenylephrine. The non-selective potassium channels blocker tetraethylammonium chloride (TEA, 10 mmol/L), ATP-sensitive potassium (KATP) channels blocker glibenclamide (10 μmol/L), and inward rectifier potassium (Kir) channels inhibitor barium chloride (BaCl2, 30 μmol/L) caused a significant inhibition on the relaxation response to RVT, whereas voltage-dependent potassium channels inhibitor 4-aminopyridine (4-AP, 1 mmol/L), and large conductance calcium-activated potassium (BKCa) channels inhibitor iberiotoxin (IbTX, 0.1 μmol/L) did not significantly alter relaxant responses of corpus cavernosum strips to RVT. In addition, relaxant responses to RVT did not significantly inhibited by the combination of selective inhibitors of small and intermediate conductance BKCa channels (0.1 μmol/L charybdotoxin and 1 μmol/L apamin, respectively). Conclusion: These results demonstrated that endothelial small and intermediate conductance BKCa channels are not thought to be an important role in RVT-induced endothelium-dependent relaxation of corpus cavernosum. The endothelium-independent corpus cavernosum relaxation induced by RVT is seems to largely depend on Kir channels and KATP channels in

  19. Characterizing the Google Books Corpus: Strong Limits to Inferences of Socio-Cultural and Linguistic Evolution.

    PubMed

    Pechenick, Eitan Adam; Danforth, Christopher M; Dodds, Peter Sheridan

    2015-01-01

    It is tempting to treat frequency trends from the Google Books data sets as indicators of the "true" popularity of various words and phrases. Doing so allows us to draw quantitatively strong conclusions about the evolution of cultural perception of a given topic, such as time or gender. However, the Google Books corpus suffers from a number of limitations which make it an obscure mask of cultural popularity. A primary issue is that the corpus is in effect a library, containing one of each book. A single, prolific author is thereby able to noticeably insert new phrases into the Google Books lexicon, whether the author is widely read or not. With this understood, the Google Books corpus remains an important data set to be considered more lexicon-like than text-like. Here, we show that a distinct problematic feature arises from the inclusion of scientific texts, which have become an increasingly substantive portion of the corpus throughout the 1900 s. The result is a surge of phrases typical to academic articles but less common in general, such as references to time in the form of citations. We use information theoretic methods to highlight these dynamics by examining and comparing major contributions via a divergence measure of English data sets between decades in the period 1800-2000. We find that only the English Fiction data set from the second version of the corpus is not heavily affected by professional texts. Overall, our findings call into question the vast majority of existing claims drawn from the Google Books corpus, and point to the need to fully characterize the dynamics of the corpus before using these data sets to draw broad conclusions about cultural and linguistic evolution. PMID:26445406

  20. Characterizing the Google Books Corpus: Strong Limits to Inferences of Socio-Cultural and Linguistic Evolution

    PubMed Central

    Pechenick, Eitan Adam; Danforth, Christopher M.; Dodds, Peter Sheridan

    2015-01-01

    It is tempting to treat frequency trends from the Google Books data sets as indicators of the “true” popularity of various words and phrases. Doing so allows us to draw quantitatively strong conclusions about the evolution of cultural perception of a given topic, such as time or gender. However, the Google Books corpus suffers from a number of limitations which make it an obscure mask of cultural popularity. A primary issue is that the corpus is in effect a library, containing one of each book. A single, prolific author is thereby able to noticeably insert new phrases into the Google Books lexicon, whether the author is widely read or not. With this understood, the Google Books corpus remains an important data set to be considered more lexicon-like than text-like. Here, we show that a distinct problematic feature arises from the inclusion of scientific texts, which have become an increasingly substantive portion of the corpus throughout the 1900s. The result is a surge of phrases typical to academic articles but less common in general, such as references to time in the form of citations. We use information theoretic methods to highlight these dynamics by examining and comparing major contributions via a divergence measure of English data sets between decades in the period 1800–2000. We find that only the English Fiction data set from the second version of the corpus is not heavily affected by professional texts. Overall, our findings call into question the vast majority of existing claims drawn from the Google Books corpus, and point to the need to fully characterize the dynamics of the corpus before using these data sets to draw broad conclusions about cultural and linguistic evolution. PMID:26445406

  1. Neuronal release of endogenous dopamine from corpus of guinea pig stomach.

    PubMed

    Shichijo, K; Sakurai-Yamashita, Y; Sekine, I; Taniyama, K

    1997-11-01

    Neuronal release of endogenous dopamine was identified in mucosa-free preparations (muscle layer including intramural plexus) from guinea pig stomach corpus by measuring tissue dopamine content and dopamine release and by immunohistochemical methods using a dopamine antiserum. Dopamine content in mucosa-free preparations of guinea pig gastric corpus was one-tenth of norepinephrine content. Electrical transmural stimulation of mucosa-free preparations of gastric corpus increased the release of endogenous dopamine in a frequency-dependent (3-20 Hz) manner. The stimulated release of dopamine was prevented by either removal of external Ca2+ or treatment with tetrodotoxin. Dopamine-immunopositive nerve fibers surrounding choline acetyltransferase-immunopositive ganglion cells were seen in the myenteric plexus of whole mount preparations of gastric corpus even after bilateral transection of the splanchnic nerve proximal to the junction with the vagal nerve (section of nerves between the celiac ganglion and stomach). Domperidone and sulpiride potentiated the stimulated release of acetylcholine and reversed the dopamine-induced inhibition of acetylcholine release from mucosa-free preparations. These results indicate that dopamine is physiologically released from neurons and from possible dopaminergic nerve terminals and regulates cholinergic neuronal activity in the corpus of guinea pig stomach. PMID:9374701

  2. Enriching a biomedical event corpus with meta-knowledge annotation

    PubMed Central

    2011-01-01

    Background Biomedical papers contain rich information about entities, facts and events of biological relevance. To discover these automatically, we use text mining techniques, which rely on annotated corpora for training. In order to extract protein-protein interactions, genotype-phenotype/gene-disease associations, etc., we rely on event corpora that are annotated with classified, structured representations of important facts and findings contained within text. These provide an important resource for the training of domain-specific information extraction (IE) systems, to facilitate semantic-based searching of documents. Correct interpretation of these events is not possible without additional information, e.g., does an event describe a fact, a hypothesis, an experimental result or an analysis of results? How confident is the author about the validity of her analyses? These and other types of information, which we collectively term meta-knowledge, can be derived from the context of the event. Results We have designed an annotation scheme for meta-knowledge enrichment of biomedical event corpora. The scheme is multi-dimensional, in that each event is annotated for 5 different aspects of meta-knowledge that can be derived from the textual context of the event. Textual clues used to determine the values are also annotated. The scheme is intended to be general enough to allow integration with different types of bio-event annotation, whilst being detailed enough to capture important subtleties in the nature of the meta-knowledge expressed in the text. We report here on both the main features of the annotation scheme, as well as its application to the GENIA event corpus (1000 abstracts with 36,858 events). High levels of inter-annotator agreement have been achieved, falling in the range of 0.84-0.93 Kappa. Conclusion By augmenting event annotations with meta-knowledge, more sophisticated IE systems can be trained, which allow interpretative information to be specified as

  3. Using text mining techniques to extract phenotypic information from the PhenoCHF corpus

    PubMed Central

    2015-01-01

    Background Phenotypic information locked away in unstructured narrative text presents significant barriers to information accessibility, both for clinical practitioners and for computerised applications used for clinical research purposes. Text mining (TM) techniques have previously been applied successfully to extract different types of information from text in the biomedical domain. They have the potential to be extended to allow the extraction of information relating to phenotypes from free text. Methods To stimulate the development of TM systems that are able to extract phenotypic information from text, we have created a new corpus (PhenoCHF) that is annotated by domain experts with several types of phenotypic information relating to congestive heart failure. To ensure that systems developed using the corpus are robust to multiple text types, it integrates text from heterogeneous sources, i.e., electronic health records (EHRs) and scientific articles from the literature. We have developed several different phenotype extraction methods to demonstrate the utility of the corpus, and tested these methods on a further corpus, i.e., ShARe/CLEF 2013. Results Evaluation of our automated methods showed that PhenoCHF can facilitate the training of reliable phenotype extraction systems, which are robust to variations in text type. These results have been reinforced by evaluating our trained systems on the ShARe/CLEF corpus, which contains clinical records of various types. Like other studies within the biomedical domain, we found that solutions based on conditional random fields produced the best results, when coupled with a rich feature set. Conclusions PhenoCHF is the first annotated corpus aimed at encoding detailed phenotypic information. The unique heterogeneous composition of the corpus has been shown to be advantageous in the training of systems that can accurately extract phenotypic information from a range of different text types. Although the scope of our

  4. Minimizing Human Intervention for Constructing Korean Part-of-Speech Tagged Corpus

    NASA Astrophysics Data System (ADS)

    Lee, Do-Gil; Hong, Gumwon; Lee, Seok Kee; Rim, Hae-Chang

    The construction of annotated corpora requires considerable manual effort. This paper presents a pragmatic method to minimize human intervention for the construction of Korean part-of-speech (POS) tagged corpus. Instead of focusing on improving the performance of conventional automatic POS taggers, we devise a discriminative POS tagger which can selectively produce either a single analysis or multiple analyses based on the tagging reliability. The proposed approach uses two decision rules to judge the tagging reliability. Experimental results show that the proposed approach can effectively control the quality of corpus and the amount of manual annotation by the threshold value of the rule.

  5. NCBI disease corpus: a resource for disease name recognition and concept normalization.

    PubMed

    Doğan, Rezarta Islamaj; Leaman, Robert; Lu, Zhiyong

    2014-02-01

    Information encoded in natural language in biomedical literature publications is only useful if efficient and reliable ways of accessing and analyzing that information are available. Natural language processing and text mining tools are therefore essential for extracting valuable information, however, the development of powerful, highly effective tools to automatically detect central biomedical concepts such as diseases is conditional on the availability of annotated corpora. This paper presents the disease name and concept annotations of the NCBI disease corpus, a collection of 793 PubMed abstracts fully annotated at the mention and concept level to serve as a research resource for the biomedical natural language processing community. Each PubMed abstract was manually annotated by two annotators with disease mentions and their corresponding concepts in Medical Subject Headings (MeSH®) or Online Mendelian Inheritance in Man (OMIM®). Manual curation was performed using PubTator, which allowed the use of pre-annotations as a pre-step to manual annotations. Fourteen annotators were randomly paired and differing annotations were discussed for reaching a consensus in two annotation phases. In this setting, a high inter-annotator agreement was observed. Finally, all results were checked against annotations of the rest of the corpus to assure corpus-wide consistency. The public release of the NCBI disease corpus contains 6892 disease mentions, which are mapped to 790 unique disease concepts. Of these, 88% link to a MeSH identifier, while the rest contain an OMIM identifier. We were able to link 91% of the mentions to a single disease concept, while the rest are described as a combination of concepts. In order to help researchers use the corpus to design and test disease identification methods, we have prepared the corpus as training, testing and development sets. To demonstrate its utility, we conducted a benchmarking experiment where we compared three different

  6. Investigation of ground-water contamination at a drainage ditch, Installation Restoration Site 4, Naval Air Station Corpus Christi, Corpus Christi, Texas, 2005–06

    USGS Publications Warehouse

    Vroblesky, Don A.; Casey, Clifton C.

    2007-01-01

    The U.S. Geological Survey, in cooperation with the Naval Facilities Engineering Command Southeast, used newly developed sampling methods to investigate ground-water contamination by chlorobenzenes beneath a drainage ditch on the southwestern side of Installation Restoration Site 4, Naval Air Station Corpus Christi, Corpus Christi, Texas, during 2005-06. The drainage ditch, which is a potential receptor for ground-water contaminants from Installation Restoration Site 4, intermittently discharges water to Corpus Christi Bay. This report uses data from a new type of pore-water sampler developed for this investigation and other methods to examine the subsurface contamination beneath the drainage ditch. Analysis of ground water from the samplers indicated that chlorobenzenes (maximum detected concentration of 160 micrograms per liter) are present in the ground water beneath the ditch. The concentrations of dissolved oxygen in the samples (less than 0.05-0.4 milligram per liter) showed that the ground water beneath and near the ditch is anaerobic, indicating that substantial chlorobenzene biodegradation in the aquifer beneath the ditch is unlikely. Probable alternative mechanisms of chlorobenzene removal in the ground water beneath the drainage ditch include sorption onto the organic-rich sediment and contaminant depletion by cattails through uptake, sorption, and localized soil aeration.

  7. 76 FR 55909 - CITGO Refining and Chemicals Company L.P. v. Port of Corpus Christi Authority of Nueces County...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-09

    ... CITGO Refining and Chemicals Company L.P. v. Port of Corpus Christi Authority of Nueces County, Texas... ``Complainant,'' against the Port of Corpus Christi Authority of Nueces County, Texas (PCCA) hereinafter... charges, CITGO has been forced to subsidize costs associated with services provided to other users of...

  8. Corpus-Driven Characterizations of Pronominal "da"-Compound Use by Learners and Native Speakers of German

    ERIC Educational Resources Information Center

    Belz, Julie A.

    2005-01-01

    This paper makes a usage-based contribution to the learning and teaching of German via the tools of contrastive learner corpus analysis (Granger, 1998; Granger, Hung, and Petch-Tyson, 2002; Nesselhauf, 2004). On the basis of an integrated learner and native speaker corpus of "telecollaborative" discourse (Belz, 2005), an empirically rich…

  9. Variation in Citational Practice in a Corpus of Student Biology Papers: From Parenthetical Plonking to Intertextual Storytelling

    ERIC Educational Resources Information Center

    Swales, John M.

    2014-01-01

    This is a corpus-based study of a key aspect of academic writing in one discipline (biology) by final-year undergraduates and first-, second-, and third-year graduate students. The papers come from the Michigan Corpus of Upper-level Student Papers, a freely available electronic database. The principal aim of the study is to examine the extent of…

  10. Sketching Muslims: A Corpus Driven Analysis of Representations around the Word "Muslim" in the British Press 1998-2009

    ERIC Educational Resources Information Center

    Baker, Paul; Gabrielatos, Costas; McEnery, Tony

    2013-01-01

    This article uses methods from corpus linguistics and critical discourse analysis to examine patterns of representation around the word "Muslim" in a 143 million word corpus of British newspaper articles published between 1998 and 2009. Using the analysis tool Sketch Engine, an analysis of noun collocates of "Muslim" found that the following…

  11. "Yes, a Very Good Point!": A Critical Genre Analysis of a Corpus of Feedback Commentaries on Master of Education Assignments

    ERIC Educational Resources Information Center

    Hyatt, David F.

    2005-01-01

    This paper seeks to use a corpus-based analysis of assessment commentaries on Master's level assignments to shed light on the guidance practices of those who provide feedback. The analysis offers a set of functional categories that emerge from the corpus and uses these to consider the degree of transparency evident in the commentaries. Based on…

  12. A Corpus-Based Evaluation of Syntactic Complexity Measures as Indices of College-Level ESL Writers' Language Development

    ERIC Educational Resources Information Center

    Lu, Xiaofei

    2011-01-01

    This article reports results of a corpus-based evaluation of 14 syntactic complexity measures as objective indices of college-level English as a second language (ESL) writers' language development. I analyzed large-scale ESL writing data from the Written English Corpus of Chinese Learners (Wen, Wang, & Liang, 2005) using a computational system…

  13. Enhancing a Process-Oriented Approach to Literacy and Language Learning: The Role of Corpus Consultation Literacy

    ERIC Educational Resources Information Center

    O'Sullivan, Ide

    2007-01-01

    Corpora and concordancing have become much more widely available as researchers recognise that they can significantly enrich the language learning environment. There is still, however, a strong resistance towards corpus use by teachers and learners (Romer, 2006:122). An understanding of the implications and relevance of corpus use for pedagogy may…

  14. An Investigation of Language Teachers' Explorations of the Use of Corpus Tools in the English for Academic Purposes (EAP) Class

    ERIC Educational Resources Information Center

    Bunting, John David

    2013-01-01

    Despite claims that the use of corpus tools can have a major impact in language classrooms (e.g., Conrad, 2000, 2004; Davies, 2004; O'Keefe, McCarthy, & Carter, 2007; Sinclair, 2004b; Tsui, 2004), many language teachers express apparent apathy or even resistance towards adding corpus tools to their repertoire (Cortes, 2013b). This study…

  15. The Most Frequently-Used Multi-Word Constructions in Academic Written English: A Multi-Corpus Study

    ERIC Educational Resources Information Center

    Liu, Dilin

    2012-01-01

    Using the academic writing sub-corpora of the Corpus of Contemporary American English and the British National Corpus as data and building on previous research, this study strives to identify the most frequently-used multi-word constructions (MWCs) of various types (e.g., idioms, lexical bundles, and phrasal/prepositional verbs) in general…

  16. The Effect of Corpus Assisted Language Teaching on the Learners' Proper Use of Punctuation Marks

    ERIC Educational Resources Information Center

    Celik, Serkan; Elkatmis, Metin

    2013-01-01

    One of the critical contributions of the emerging technologies in computer sciences is the capability of corpus compilation and processing. Corpus resources and approaches are regarded as a potentially valuable areas both in developing instructional methods and designing pedagogical materials. This study aimed to explore the effect of exposing…

  17. Analyzing Idioms and Their Frequency in Three Advanced ILI Textbooks: A Corpus-Based Study

    ERIC Educational Resources Information Center

    Alavi, Sepideh; Rajabpoor, Aboozar

    2015-01-01

    The present study aimed at identifying and quantifying the idioms used in three ILI "Advanced" level textbooks based on three different English corpora; MICASE, BNC and the Brown Corpus, and comparing the frequencies of the idioms across the three corpora. The first step of the study involved searching the books to find multi-word…

  18. The Impact of Corpus-Based Collocation Instruction on Iranian EFL Learners' Collocation Learning

    ERIC Educational Resources Information Center

    Ashouri, Shabnam; Arjmandi, Masoume; Rahimi, Ramin

    2014-01-01

    Over the past decades, studies of EFL/ESL vocabulary acquisition have identified the significance of collocations in language learning. Due to the fact that collocations have been regarded as one of the major concerns of both EFL teachers and learners for many years, the present study attempts to shed light on the impact of corpus-based…

  19. Two Different Faces of Cavafy in English: A Corpus-Assisted Approach to Translational Stylistics

    ERIC Educational Resources Information Center

    Pantopoulos, Iraklis

    2012-01-01

    A translator is seen to leave a personal mark on the text through their stylistic choices and the patterns formed by these choices. This article comprises a case study that uses a specialized comparative corpus containing translations of C.P. Cavafy's canon in order to explore the distinctive stylistic features of Rae Dalven and of Edmund…

  20. Capturing the Dynamics of Second Language Development via Learner Corpus Research: A Very Long Engagement

    ERIC Educational Resources Information Center

    Hasko, Victoria

    2013-01-01

    This introductory paper highlights the promising potential of learner corpora to facilitate investigations of the developmental processes underlying L2 learning. It offers a critical discussion of the aspects in which the disciplines of learner corpus (LC) research and SLA would benefit from closer interdisciplinary engagement and introduces the…

  1. Discourse Particles in Corpus Data and Textbooks: The Case of "Well"

    ERIC Educational Resources Information Center

    Lam, Phoenix W. Y.

    2010-01-01

    Discourse particles are ubiquitous in spoken discourse. Yet despite their pervasiveness very few studies attempt to look at their use in the pedagogical setting. Drawing on data from an intercultural corpus of speech and a textbook database, the present study compares the use of discourse particles by expert users of English in Hong Kong with…

  2. Writing/Thinking in Real Time: Digital Video and Corpus Query Analysis

    ERIC Educational Resources Information Center

    Park, Kwanghyun; Kinginger, Celeste

    2010-01-01

    The advance of digital video technology in the past two decades facilitates empirical investigation of learning in real time. The focus of this paper is the combined use of real-time digital video and a networked linguistic corpus for exploring the ways in which these technologies enhance our capability to investigate the cognitive process of…

  3. Inspecting the Unexpected: Language Status and Corpus Shifts as Aspects of Quichua Language Revitalization.

    ERIC Educational Resources Information Center

    King, Kendall A.

    1999-01-01

    Drawing from the study of efforts to revitalize Quichua in the Southern Ecuadorian Highlands, this article describes what may be some of the common language corpus and language status transformations that threatened languages undergo during the process of language revitalization. (Author/VWL)

  4. The Case of Perrin and Thomson: An Example of the Use of a Mini-Corpus

    ERIC Educational Resources Information Center

    Banks, David

    2005-01-01

    Although recent trends have been towards large corpora, there is a valid place for the study of small corpora. This article is an example of one such study using a corpus of late 19th century texts, consisting of 1783 words in French by Perrin, and 2824 words in English by Thomson. Perrin uses more first person pronouns in a wider range of…

  5. Corpus Study of Tense, Aspect, and Modality in Diglossic Speech in Cairene Arabic

    ERIC Educational Resources Information Center

    Moshref, Ola Ahmed

    2012-01-01

    Morpho-syntactic features of Modern Standard Arabic mix intricately with those of Egyptian Colloquial Arabic in ordinary speech. I study the lexical, phonological and syntactic features of verb phrase morphemes and constituents in different tenses, aspects, moods. A corpus of over 3000 phrases was collected from religious, political/economic and…

  6. Tracking Learners' Actual Uses of Corpora: Guided vs Non-Guided Corpus Consultation

    ERIC Educational Resources Information Center

    Perez-Paredes, Pascual; Sanchez-Tornel, Maria; Calero, Jose Maria Alcaraz; Jimenez, Pilar Aguado

    2011-01-01

    Much of the research into language learners' use of corpus resources has been conducted by means of indirect observation methodologies, like questionnaires or self-reports. While this type of study provides an excellent opportunity to reflect on the benefits and limitations of using corpora to teach and learn language, the use of indirect…

  7. 40 CFR 81.136 - Corpus Christi-Victoria Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Corpus Christi-Victoria Intrastate Air Quality Control Region. 81.136 Section 81.136 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... County, Jackson County, Jim Wells County, Kenedy County, Kleberg County, Lavaca County, Live Oak...

  8. How Can We Use Corpus Wordlists for Language Learning? Interfaces between Computer Corpora and Expert Intervention

    ERIC Educational Resources Information Center

    Chen, Yu-Hua; Bruncak, Radovan

    2015-01-01

    With the advances in technology, wordlists retrieved from computer corpora have become increasingly popular in recent years. The lexical items in those wordlists are usually selected, according to a set of robust frequency and dispersion criteria, from large corpora of authentic and naturally occurring language. Corpus wordlists are of great value…

  9. IMPACT OF STORM-WATER OUTFALLS ON SEDIMENT QUALITY IN CORPUS CHRISTI BAY, TEXAS, USA

    EPA Science Inventory

    To determine the quality of sediments and extent of contaminant impacts, a Sediment Quality Triad (SQT) study was conducted at 36 sites in the Corpus Christi Bay, Texas, USA, system. Fifteen of the 36 sites were located near storm-water outfalls, but 13 other sites (i.e., industr...

  10. Lexical Bundles in Discourse Structure: A Corpus-Based Study of Classroom Discourse

    ERIC Educational Resources Information Center

    Csomay, Eniko

    2013-01-01

    The present study applies corpus-based methods to document the distributional patterns of previously reported lexical bundle functions as they relate to discourse structure. Specifically, 84 lexical bundles and their discourse functions (Biber "et al." 2004a) were tracked in 1,176 discourse units extracted from the initial phases of 196 university…

  11. Stylizing Genderlect Online for Social Action: A Corpus Analysis of "BIC Cristal for Her" Reviews

    ERIC Educational Resources Information Center

    Ray, Brian

    2016-01-01

    This article introduces the concept of stylization and illustrates its usefulness for studying online discourse by examining how writers have employed it in order to parody sexist products such as BIC Cristal for Her, using genderlect in order to introduce dissonance into and reframe patriarchal discourse. A corpus analysis of 671 reviews, written…

  12. Exploiting a Corpus of Business Letters from a Phraseological, Functional Perspective

    ERIC Educational Resources Information Center

    Flowerdew, Lynne

    2012-01-01

    This paper illustrates how a freely available online corpus has been exploited in a module on teaching business letters covering the following four speech acts (functions) commonly found in business letters: invitations, requests, complaints and refusals. It is proposed that different strategies are required for teaching potentially…

  13. Cognitive Genre Structures in Methods Sections of Research Articles: A Corpus Study

    ERIC Educational Resources Information Center

    Bruce, Ian

    2008-01-01

    This paper reports a corpus investigation of the Methods sections of research-reporting articles in academic journals. In published pedagogic materials, Swales and Feak [Swales, J. M., & Feak, C. (1994). Academic writing for graduate students. Ann Arbor: University of Michigan Press; Swales, J. M., & Feak, C. (2000). English in today's research…

  14. Teaching English as a Friendly Language: Lessons from the SCOTS Corpus

    ERIC Educational Resources Information Center

    Anderson, Wendy; Corbett, John

    2010-01-01

    This paper uses the interactional spoken data contained in the Scottish Corpus of Texts & Speech (SCOTS) to investigate "friendly" language and shows how its principles can inform a model of language for learners of English as a second or foreign language. Pragmatic markers used in local speech varieties are in danger of being neglected in an…

  15. Incorporating Corpus Technology to Facilitate Learning of English Collocations in a Thai University EFL Writing Course

    ERIC Educational Resources Information Center

    Chatpunnarangsee, Kwanjira

    2013-01-01

    The purpose of this study is to explore ways of incorporating web-based concordancers for the purpose of teaching English collocations. A mixed-methods design utilizing a case study strategy was employed to uncover four specific dimensions of corpus use by twenty-four students in two classroom sections of a writing course at a university in…

  16. A Corpus-Based Evaluation of Metaphors in a Business English Textbook

    ERIC Educational Resources Information Center

    Skorczynska Sznajder, Hanna

    2010-01-01

    This study aims to evaluate the selection of metaphors in a published business English textbook using findings from a specialised corpus of written business English. While most scholars agree that metaphors should be included in English for Specific Purposes (ESP) syllabuses as a potentially problematic area in successful language learning, it is…

  17. A Corpus-Based Study of Malaysian ESL Learners' Use of Modals in Argumentative Compositions

    ERIC Educational Resources Information Center

    Kader, Mohamed Ismail bin Abdul; Begi, Neda; Vaseghi, Reza

    2013-01-01

    This study attempts to examine the use of English modals in terms of their frequency and functions. For this purpose, Form 4 and College students' argumentative compositions were extracted from the Malaysian Corpus of Students' Argumentative Writing (MCSAW). In order to analyze the data, this study employed discourse analysis and some descriptive…

  18. A Pedagogic Corpus Analysis: Modal Auxiliary Verbs in Malaysian English Textbooks

    ERIC Educational Resources Information Center

    Khojasteh, Laleh; Mukundan, Jayakaran

    2011-01-01

    Using corpus approach, over the past two decades, a growing number of researchers started to blame textbooks for neglecting important information on the use of grammatical structures in real language use and provided ample information about the mismatch between language used in textbooks and real language in use. Likewise, the prescribed Malaysian…

  19. Corpora in Language Teaching and Learning: Potential, Evaluation, Challenges. English Corpus Linguistics. Volume 13

    ERIC Educational Resources Information Center

    Breyer, Yvonne Alexandra

    2011-01-01

    This book highlights the potential and the challenges of corpora in language education with a particular focus on the teacher's perspective. For this purpose, the study explores the relevance of the corpus approach to central paradigms underlying contemporary language education. Furthermore, a critical analysis investigates the persisting gap…

  20. The Most Frequently Used Spoken American English Idioms: A Corpus Analysis and Its Implications

    ERIC Educational Resources Information Center

    Liu, Dilin

    2003-01-01

    Most teaching and reference materials on English idioms are primarily intuition based. As such, they often include seldom-used idioms and incorrect descriptions of the meaning and use of some idioms, hence limiting their usefulness to ESOL students. This article demonstrates how this problem can be addressed through a corpus-based study of the…

  1. "Wireless": Some Facts and Figures from a Corpus-Driven Study

    ERIC Educational Resources Information Center

    Rizzo, Camino Rea

    2009-01-01

    "Wireless" is the word selected to illustrate a model of analysis designed to determine the specialized character of a lexical unit. "Wireless" belongs to the repertoire of specialized vocabulary automatically extracted from a corpus of telecommunication engineering English (TEC). This paper describes the procedure followed in the analysis which…

  2. Building an Effective Speech Corpus by Utilizing Statistical Multidimensional Scaling Method

    NASA Astrophysics Data System (ADS)

    Nagino, Goshu; Shozakai, Makoto; Toda, Tomoki; Saruwatari, Hiroshi; Shikano, Kiyohiro

    This paper proposes a technique for building an effective speech corpus with lower cost by utilizing a statistical multidimensional scaling method. The statistical multidimensional scaling method visualizes multiple HMM acoustic models into two-dimensional space. At first, a small number of voice samples per speaker is collected; speaker adapted acoustic models trained with collected utterances, are mapped into two-dimensional space by utilizing the statistical multidimensional scaling method. Next, speakers located in the periphery of the distribution, in a plotted map are selected; a speech corpus is built by collecting enough voice samples for the selected speakers. In an experiment for building an isolated-word speech corpus, the performance of an acoustic model trained with 200 selected speakers was equivalent to that of an acoustic model trained with 533 non-selected speakers. It means that a cost reduction of more than 62% was achieved. In an experiment for building a continuous word speech corpus, the performance of an acoustic model trained with 500 selected speakers was equivalent to that of an acoustic model trained with 1179 non-selected speakers. It means that a cost reduction of more than 57% was achieved.

  3. The Genre of Instructor Feedback in Doctoral Programs: A Corpus Linguistic Analysis

    ERIC Educational Resources Information Center

    Walters, Kelley Jo; Henry, Patricia; Vinella, Michael; Wells, Steve; Shaw, Melanie; Miller, James

    2015-01-01

    Providing transparent written feedback to doctoral students is essential to the learning process and preparation for the capstone. The purpose of this study was to conduct a qualitative exploration of faculty feedback on benchmark written assignments across multiple, online doctoral programs. The Corpus for this analysis included 236 doctoral…

  4. ATF3 Expression in the corpus luteum: possible role in luteal regression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The present study investigated the induction and possible role of activating transcription factor 3 (ATF3) in the corpus luteum. Postpubertal cattle were treated at midcycle with prostaglandin F2alpha(PGF) for 0–4 hours. Luteal tissue was processed for immunohistochemistry, in situ hybridization, an...

  5. Integrating Corpus-Based CALL Programs in Teaching English through Children's Literature

    ERIC Educational Resources Information Center

    Johns, Tim F.; Hsingchin, Lee; Lixun, Wang

    2008-01-01

    This paper presents particular pedagogical applications of a number of corpus-based CALL (computer assisted language learning) programs such as "CONTEXTS" and "CLOZE," "MATCHUP" and "BILINGUAL SENTENCE SHUFFLER," in the teaching of English through children's literature. An elective course in Taiwan for school students aged 17-18, based on a…

  6. Tag Questions across Irish English and British English: A Corpus Analysis of Form and Function

    ERIC Educational Resources Information Center

    Barron, Anne; Pandarova, Irina; Muderack, Karoline

    2015-01-01

    The present study, situated in the area of variational pragmatics, contrasts tag question (TQ) use in Ireland and Great Britain using spoken data from the Irish and British components of the International Corpus of English (ICE). Analysis is on the formal and functional level and also investigates form-functional relationships. Findings reveal…

  7. Specific Syntactic Complexity: Developmental Profiling of Individuals Based on an Annotated Learner Corpus

    ERIC Educational Resources Information Center

    Vyatkina, Nina

    2013-01-01

    This study tracks the development of syntactic complexity in the writing of two beginning German as a second language learners with English as a first language over four semesters of collegiate language study by using developmental profiling techniques applied to an annotated learner corpus. The focus of the investigation is on individual…

  8. Grammar and Lexicon in Individuals with Autism: A Quantitative Analysis of a Large Italian Corpus

    ERIC Educational Resources Information Center

    Tuzzi, Arjuna

    2009-01-01

    Statistical and linguistic procedures were implemented to analyze a large corpus of texts written by 37 individuals with autism and 92 facilitators (without disabilities), producing written conversations by means of PCs. Such texts were compared and contrasted to identify the specific traits of the lexis of the group of individuals with autism and…

  9. A unified approach for development of Urdu Corpus for OCR and demographic purpose

    NASA Astrophysics Data System (ADS)

    Choudhary, Prakash; Nain, Neeta; Ahmed, Mushtaq

    2015-02-01

    This paper presents a methodology for the development of an Urdu handwritten text image Corpus and application of Corpus linguistics in the field of OCR and information retrieval from handwritten document. Compared to other language scripts, Urdu script is little bit complicated for data entry. To enter a single character it requires a combination of multiple keys entry. Here, a mixed approach is proposed and demonstrated for building Urdu Corpus for OCR and Demographic data collection. Demographic part of database could be used to train a system to fetch the data automatically, which will be helpful to simplify existing manual data-processing task involved in the field of data collection such as input forms like Passport, Ration Card, Voting Card, AADHAR, Driving licence, Indian Railway Reservation, Census data etc. This would increase the participation of Urdu language community in understanding and taking benefit of the Government schemes. To make availability and applicability of database in a vast area of corpus linguistics, we propose a methodology for data collection, mark-up, digital transcription, and XML metadata information for benchmarking.

  10. Task Dependency Effects of Collaboration in Learners' Corpus Consultation: An Exploratory Case Study

    ERIC Educational Resources Information Center

    Cho, Hyeyoung

    2016-01-01

    Collaborative learning has attracted attention as pedagogic mediation to assist learners' corpus consultation, but some studies have pointed to negative aspects of collaboration. Based on the two sides of collaboration in language learning, this study presents a qualitative investigation of different effects of collaboration depending on task…

  11. A Corpus Analysis of Vocabulary Coverage and Vocabulary Learning Opportunities within a Children's Story Series

    ERIC Educational Resources Information Center

    Sun, Yu-Chih

    2016-01-01

    Extensive reading for second language learners have been widely documented over the past few decades. However, few studies, if any, have used a corpus analysis approach to analyze the vocabulary coverage within a single-author story series, its repetition of vocabulary, and the incidental and intentional vocabulary learning opportunities therein.…

  12. A Text Corpus Approach to an Analysis of the Shared Use of Core Terminology.

    ERIC Educational Resources Information Center

    Patrick, Timothy B.; Sievert, MaryEllen; Reid, John C.; Rice, Frances Ellis; Gigantelli, James W.; Schiffman, Jade S.; Shelton, Mark E.

    2003-01-01

    Investigates the shared use of core Ophthalmology terms in the domains of Ophthalmology, Family Practice and Radiology. Core terms were searched for in a text corpus of 38,695 MEDLINE abstracts covering 1970-1999 from journals representing the three domains. Findings indicated core Ophthalmology terms were used significantly more by Ophthalmology…

  13. Listen, Listen, Listen and Listen: Building a Comprehension Corpus and Making It Comprehensible

    ERIC Educational Resources Information Center

    Mordaunt, Owen G.; Olson, Daniel W.

    2010-01-01

    Listening comprehension input is necessary for language learning and acculturation. One approach to developing listening comprehension skills is through exposure to massive amounts of naturally occurring spoken language input. But exposure to this input is not enough; learners also need to make the comprehension corpus meaningful to their learning…

  14. Utilizing Lexical Data from a Web-Derived Corpus to Expand Productive Collocation Knowledge

    ERIC Educational Resources Information Center

    Wu, Shaoqun; Witten, Ian H.; Franken, Margaret

    2010-01-01

    Collocations are of great importance for second language learners, and a learner's knowledge of them plays a key role in producing language fluently (Nation, 2001: 323). In this article we describe and evaluate an innovative system that uses a Web-derived corpus and digital library software to produce a vast concordance and present it in a way…

  15. A Study of Composition/Correction System with Corpus Retrieval Function

    ERIC Educational Resources Information Center

    Liu, Song; Liu, Peng; Urano, Yoshiyori

    2013-01-01

    Practice and research in the composition education that is using computer and network have been more and more active. Through online composition system, a large amount of written texts produced by students and teachers can be collected. This kind of information is called a learner corpus, which is important in second language education because the…

  16. Putting the CEFR to Good Use: Designing Grammars Based on Learner-Corpus Evidence

    ERIC Educational Resources Information Center

    McCarthy, Michael

    2016-01-01

    This lecture considers what reference and pedagogical grammars and grammar teaching materials for L2 learners should ideally include, based on corpus evidence from both native-speaker and learner corpora. I demonstrate how learner corpora can be used to track the emergence of grammatical features, from the elementary level to advanced, how…

  17. Using a Corpus-Based Lexicogrammatical Approach to Grammar Instruction in EFL and ESL Contexts

    ERIC Educational Resources Information Center

    Liu, Dilin; Jiang, Ping

    2009-01-01

    This article reports on a study that examined the effects of integrating corpus and contextualized lexicogrammar in foreign and second language teaching. The study was conducted in English as a foreign language (EFL) and English as a second language (ESL) courses at 1 Chinese university and 2 U.S. universities, involving 244 participants (236…

  18. The Effect of Corpus-Based Activities on Verb-Noun Collocations in EFL Classes

    ERIC Educational Resources Information Center

    Ucar, Serpil; Yükselir, Ceyhun

    2015-01-01

    This current study sought to reveal the impacts of corpus-based activities on verb-noun collocation learning in EFL classes. This study was carried out on two groups--experimental and control groups- each of which consists of 15 students. The students were preparatory class students at School of Foreign Languages, Osmaniye Korkut Ata University.…

  19. Factors associated with birth defects in the region of Corpus Christi, Texas

    EPA Science Inventory

    In recent years, the Birth Defects Epidemiology & Surveillance Branch of the Texas Department of State Health Services (DSHS) has documented a high prevalence of certain birth defects in the Corpus Christi, TX region. We conducted a case-control study to evaluate associations...

  20. The Development of Second Language Writing Complexity in Groups and Individuals: A Longitudinal Learner Corpus Study

    ERIC Educational Resources Information Center

    Vyatkina, Nina

    2012-01-01

    This study explores the development of multiple dimensions of linguistic complexity in the writing of beginning learners of German both as a group and as individuals. The data come from an annotated, longitudinal learner corpus. The development of lexicogrammatical complexity is explored at 2 intersections: (a) between cross-sectional trendlines…

  1. On the Application of Corpus of Contemporary American English in Vocabulary Instruction

    ERIC Educational Resources Information Center

    Yusu, Xu

    2014-01-01

    The development of corpus linguistics has laid theoretical foundation and provided technical support for breaking the bottleneck in traditional vocabulary instruction in China. Corpora allow access to authentic data and show frequency patterns of words and grammar construction. Such patterns can be used to improve language materials or to directly…

  2. Tracking Learners' Progress: Adopting a Dual "Corpus cum Experimental Data" Approach

    ERIC Educational Resources Information Center

    Meunier, Fanny; Littre, Damien

    2013-01-01

    The article discusses the potential of combining learner corpus research with experimental studies in order to fine-tune the understanding of learner language development. It illustrates the complementarity of the two methodological approaches with data from an ongoing study of the acquisition of the English tense and aspect system by French…

  3. Issues Related to the Construction of a Purpose-Built Domain-Specific Word Corpus

    ERIC Educational Resources Information Center

    Thomas, Lisa; Pfister, H. Peter; Peterson, Peter

    2004-01-01

    There is growing interest in the use of semantic collections in order to identify and analyse domain knowledge. This paper describes some technical issues to consider when contemplating research which incorporates small-to-medium domain-specific word sets. The purpose of the corpus construction described was to provide an external word collection…

  4. NCBI Disease Corpus: A Resource for Disease Name Recognition and Concept Normalization

    PubMed Central

    Doğan, Rezarta Islamaj; Leaman, Robert; Lu, Zhiyong

    2014-01-01

    Information encoded in natural language in biomedical literature publications is only useful if efficient and reliable ways of accessing and analyzing that information are available. Natural language processing and text mining tools are therefore essential for extracting valuable information, however, the development of powerful, highly effective tools to automatically detect central biomedical concepts such as diseases is conditional on the availability of annotated corpora. This paper presents the disease name and concept annotations of the NCBI disease corpus, a collection of 793 PubMed abstracts fully annotated at the mention and concept level to serve as a research resource for the biomedical natural language processing community. Each PubMed abstract was manually annotated by two annotators with disease mentions and their corresponding concepts in Medical Subject Headings (MeSH®) or Online Mendelian Inheritance in Man (OMIM®). Manual curation was performed using PubTator, which allowed the use of pre-annotations as a pre-step to manual annotations. Fourteen annotators were randomly paired and differing annotations were discussed for reaching a consensus in two annotation phases. In this setting, a high inter-annotator agreement was observed. Finally, all results were checked against annotations of the rest of the corpus to assure corpus-wide consistency. The public release of the NCBI disease corpus contains 6,892 disease mentions, which are mapped to 790 unique disease concepts. Of these, 88% link to a MeSH identifier, while the rest contain an OMIM identifier. We were able to link 91% of the mentions to a single disease concept, while the rest are described as a combination of concepts. In order to help researchers use the corpus to design and test disease identification methods, we have prepared the corpus as training, testing and development sets. To demonstrate its utility, we conducted a benchmarking experiment where we compared three different

  5. Comparison of Smoking, Drinking, and Marijuana Use between Students Present or Absent on the Day of a School-Based Survey

    ERIC Educational Resources Information Center

    Bovet, Pascal; Viswanathan, Bharathi; Faeh, David; Warren, Wick

    2006-01-01

    The aim of this population-based survey was to compare the prevalence of selected risk behaviors between students present or absent on the day of a school-based survey. The study population was a representative sample of all students of secondary schools in the Seychelles (Indian Ocean). Students absent on the day of the survey were traced and…

  6. A symptomatic neonate with tetralogy of Fallot, an absent pulmonary valve, and a single coronary artery with a major fistula.

    PubMed

    Kajihara, Noriyoshi; Asou, Toshihide; Takeda, Yuko; Kosaka, Yoshimichi; Matsuhama, Minoru; Onakatomi, Yasuko; Yanagi, Sadamitsu; Yasui, Seiyo

    2009-11-01

    We present a case with a rare combination of tetralogy of Fallot with an absent pulmonary valve, and a single coronary artery with a major fistula to the main pulmonary artery. Myocardial ischemia developed in response to increasing shunt flow through the coronary fistula, resulting in heart failure. We ligated the coronary fistula and plicated the anterior wall of the dilated pulmonary arteries during the neonatal period. Complete repair through a transatrial-transpulmonary approach was performed at the age of 17 months. The postoperative course was excellent and the patient maintained a stable hemodynamic and respiratory state with no evidence of myocardial ischemia. PMID:19853139

  7. Absent husbands, single wives: success, domesticity, and seminuclear families in the nineteenth-century Great Lakes world.

    PubMed

    Nutting, P Bradley

    2010-01-01

    The industrial and transportation revolutions of nineteenth-century America separated work from home (at least for the growing middle class) and intensified the development of masculine and feminine spheres devoted to success and domesticity, respectively. This development tended to reduce the husband's traditional patriarchal roles to that of provider only, while leaving the wife and mother with enhanced authority over household management and child rearing, a development with consequences for feminism. This article examines two extreme cases of separation of work from home: absent husbands, respected professional men, who left their wives alone for months or years and, while they provided financial support, surrendered all household authority to "single" wives. PMID:21105493

  8. Human corpus luteum: presence of epidermal growth factor receptors and binding characteristics

    SciTech Connect

    Ayyagari, R.R.; Khan-Dawood, F.S.

    1987-04-01

    Epidermal growth factor receptors are present in many reproductive tissues but have not been demonstrated in the human corpus luteum. To determine the presence of epidermal growth factor receptors and its binding characteristics, we carried out studies on the plasma cell membrane fraction of seven human corpora lutea (days 16 to 25) of the menstrual cycle. Specific epidermal growth factor receptors were present in human corpus luteum. Insulin, nerve growth factor, and human chorionic gonadotropin did not competitively displace epidermal growth factor binding. The optimal conditions for corpus luteum-epidermal growth factor receptor binding were found to be incubation for 2 hours at 4 degrees C with 500 micrograms plasma membrane protein and 140 femtomol /sup 125/I-epidermal growth factor per incubate. The number (mean +/- SEM) of epidermal growth factor binding sites was 12.34 +/- 2.99 X 10(-19) mol/micrograms protein; the dissociation constant was 2.26 +/- 0.56 X 10(-9) mol/L; the association constant was 0.59 +/- 0.12 X 10(9) L/mol. In two regressing corpora lutea obtained on days 2 and 3 of the menstrual cycle, there was no detectable specific epidermal growth factor receptor binding activity. Similarly no epidermal growth factor receptor binding activity could be detected in ovarian stromal tissue. Our findings demonstrate that specific receptors for epidermal growth factor are present in the human corpus luteum. The physiologic significance of epidermal growth factor receptors in human corpus luteum is unknown, but epidermal growth factor may be involved in intragonadal regulation of luteal function.

  9. Steroid regulation of early postnatal development in the corpus epididymidis of pigs.

    PubMed

    Katleba, Kimberley D; Legacki, Erin L; Conley, Alan J; Berger, Trish

    2015-06-01

    Development of the epididymis including blood-epididymal barrier formation is not required until sperm reach the epididymis peripuberally. Regulation of this development in the early postnatal period is largely unknown. The current objectives were to evaluate potential roles of endogenous estrogen and androgen signaling during early development of the corpus epididymidis and to determine the timing of formation of the blood-epididymal barrier in the pig. Effects of endogenous steroids were evaluated using littermates treated with vehicle, an aromatase inhibitor (letrozole) to reduce endogenous estrogens, an estrogen receptor antagonist (fulvestrant) or an androgen receptor antagonist (flutamide). Phosphorylated histone 3 immunohistochemistry was used to identify proliferating epithelial cells. Lanthanum nitrate and electron microscopy were used to analyze formation of the blood barrier in the corpus epididymidis. Reducing endogenous estrogens increased the number of proliferating corpus epithelial cells at 6 and 6.5 weeks of age compared with vehicle-treated boars (P<0.01 and P<0.001 respectively). Blocking androgen receptors did not alter proliferation rate at 6.5 weeks of age. Although barrier formation was similar between 6 and 6.5 weeks of age in vehicle-treated animals, intercellular barriers increased in letrozole-treated littermates at 6.5 weeks of age. Fulvestrant treatment, which should mimic aromatase inhibition for regulation through ESR1 and ESR2 signaling but potentially stimulate endogenous estrogen signaling through the G protein-coupled estrogen receptor (GPER), had the opposite effect on aromatase inhibition. These responses in conjunction with the presence of GPER in the corpus epididymidis suggest early corpus epididymal development is regulated partially by GPER. PMID:25876610

  10. The retinal determination gene eyes absent is regulated by the EGF receptor pathway throughout development in Drosophila.

    PubMed

    Salzer, Claire L; Elias, Yair; Kumar, Justin P

    2010-01-01

    Members of the Eyes absent (Eya) protein family play important roles in tissue specification and patterning by serving as both transcriptional activators and protein tyrosine phosphatases. These activities are often carried out in the context of complexes containing members of the Six and/or Dach families of DNA binding proteins. eyes absent, the founding member of the Eya family is expressed dynamically within several embryonic, larval, and adult tissues of the fruit fly, Drosophila melanogaster. Loss-of-function mutations are known to result in disruptions of the embryonic head and central nervous system as well as the adult brain and visual system, including the compound eyes. In an effort to understand how eya is regulated during development, we have carried out a genetic screen designed to identify genes that lie upstream of eya and govern its expression. We have identified a large number of putative regulators, including members of several signaling pathways. Of particular interest is the identification of both yan/anterior open and pointed, two members of the EGF Receptor (EGFR) signaling cascade. The EGFR pathway is known to regulate the activity of Eya through phosphorylation via MAPK. Our findings suggest that this pathway is also used to influence eya transcriptional levels. Together these mechanisms provide a route for greater precision in regulating a factor that is critical for the formation of a wide range of diverse tissues. PMID:19884307

  11. The Retinal Determination Gene eyes absent Is Regulated by the EGF Receptor Pathway Throughout Development in Drosophila

    PubMed Central

    Salzer, Claire L.; Elias, Yair; Kumar, Justin P.

    2010-01-01

    Members of the Eyes absent (Eya) protein family play important roles in tissue specification and patterning by serving as both transcriptional activators and protein tyrosine phosphatases. These activities are often carried out in the context of complexes containing members of the Six and/or Dach families of DNA binding proteins. eyes absent, the founding member of the Eya family is expressed dynamically within several embryonic, larval, and adult tissues of the fruit fly, Drosophila melanogaster. Loss-of-function mutations are known to result in disruptions of the embryonic head and central nervous system as well as the adult brain and visual system, including the compound eyes. In an effort to understand how eya is regulated during development, we have carried out a genetic screen designed to identify genes that lie upstream of eya and govern its expression. We have identified a large number of putative regulators, including members of several signaling pathways. Of particular interest is the identification of both yan/anterior open and pointed, two members of the EGF Receptor (EGFR) signaling cascade. The EGFR pathway is known to regulate the activity of Eya through phosphorylation via MAPK. Our findings suggest that this pathway is also used to influence eya transcriptional levels. Together these mechanisms provide a route for greater precision in regulating a factor that is critical for the formation of a wide range of diverse tissues. PMID:19884307

  12. Absent right and persistent left superior vena cava: troubleshooting during a challenging pacemaker implant: a case report

    PubMed Central

    2014-01-01

    Background Venous anomalies of the thorax can occur in isolation or in association with complex congenital heart disease. The incidence of an absent right superior vena cava in the setting of a persistent left superior vena cava is very rare in the general population with only a dozen cases documented in the medical literature. Such venous anomalies can make for very challenging electronic cardiac device implantation. We report our challenging dual chamber pacemaker implant in a patient with such complex anatomy and focus on our implantation technique that helped achieve adequate lead positioning. Case presentation A 73-year-old Caucasian female with degenerative complete heart block presented for dual chamber permanent pacemaker implant. Lead implantation was very challenging due to abnormal and rare vena cava anatomy; a persistent left superior vena cava drained directly into the coronary sinus and the right brachiocephalic vein drained directly into the left persistent superior vena cava as the patient had an absent right superior vena cava . Adequate right ventricular lead positioning was achieved following numerous lead-stylet manipulations and careful looping in the atria to redirect its trajectory to the ventricular apex. Conclusion Abnormal superior vena cava development is uncommon and can lead to technical challenges when venous access is required during various interventional procedures. Pre-operative imaging can help identify such challenging anatomy allowing appropriate operative planning; careful patient selection is warranted for venography given the risk of contrast nephrotoxicity. PMID:25047923

  13. Condition at birth of infants with previously absent or reverse umbilical artery end-diastolic flow velocities.

    PubMed

    Weiss, E; Ulrich, S; Berle, P

    1992-01-01

    In a case control study we assessed 47 fetuses with absent or reverse end-diastolic flow velocities (AREDFV) of the umbilical artery with respect to the mode of delivery, fetal acidosis, and abnormal neurological evaluations at the time of discharge from the department of pediatrics. We also studied a control group which was matched for gestational age and had normal umbilical artery flow velocity waveforms. Fetuses with AREDFV were delivered almost exclusively by cesarean section which was usually done for fetal distress. The number of fetuses with abnormal neurological signs was significantly increased compared to the control group. Fetuses with AREDFV showed an increased incidence of fetal acidosis. Forty per cent of these fetuses were delivered within one day of the first abnormal flow measurement; Sixty per cent were observed clinically for up to four weeks before delivery. PMID:1417086

  14. Vestibular responses to linear acceleration are absent in otoconia-deficient C57BL/6JEi-het mice

    NASA Technical Reports Server (NTRS)

    Jones, S. M.; Erway, L. C.; Bergstrom, R. A.; Schimenti, J. C.; Jones, T. A.

    1999-01-01

    Vestibular evoked potentials (VsEPs) were measured in normal mice and in mice homozygous for the head tilt mutation (het/het, abbr. het). The het mice lack otoconia, the inertial mass critical for natural stimulation of inner ear gravity receptors. Our findings demonstrate that vestibular neural responses to pulsed linear acceleration are absent in het mice. The results: (1) confirm that adequate sensory stimuli fail to activate gravity receptors in the het model; and (2) serve as definitive evidence that far-field vestibular responses to pulsed linear acceleration depend critically on otolith end organs. The C57BL/6JEi-het mouse may be an excellent model of gravity receptor sensory deprivation.

  15. Mesonephric carcinoma of the uterine corpus: A report of two cases

    PubMed Central

    ZHAO, JIANGUO; LIU, CAIYAN; QI, JI; QU, PENGPENG

    2016-01-01

    Mesonephric carcinoma of the uterine corpus is an extremely rare malignancy that originates from the mesonephric remnant of the female reproductive tract. There have been no previous reports of mesonephric carcinoma accompanied by a sarcomatous component. The current study presents two cases of uterine corpus mesonephric carcinoma with sarcomatous components that occurred in postmenopausal women. Immunohistochemically, the tumour cells were positive for vimentin and CD10. The tumours of these patients were located in the uterine myometrium; therefore, treatment was similar to that for endometrial cancer. Although the follow-up period was short in the current cases, no metastatic disease was identified in the second case and thus, this may increase clinical knowledge with regard to the biological behavior of these rare malignancies. PMID:26870213

  16. Supporting English-medium pedagogy through an online corpus of science and engineering lectures

    NASA Astrophysics Data System (ADS)

    Kunioshi, Nílson; Noguchi, Judy; Tojo, Kazuko; Hayashi, Hiroko

    2016-05-01

    As English-medium instruction (EMI) spreads around the world, university teachers and students who are non-native speakers of English (NNS) need to put much effort into the delivery or reception of content. Construction of scientific meaning in the process of learning is already complex when instruction is delivered in the first language of the teachers and students, and may become even more challenging in a second language, because science education depends greatly on language. In order to identify important pedagogical functions that teachers use to deliver content and to present different ways to realise each function, a corpus of lectures related to science and engineering courses was created and analysed. NNS teachers and students in science and engineering involved in EMI higher education can obtain insights for delivering and listening to lectures from the Online Corpus of Academic Lectures (OnCAL).

  17. 78 FR 44523 - Reorganization of Foreign-Trade Zone 122 Under Alternative Site Framework; Corpus Christi, Texas

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-24

    ...; Whereas, notice inviting public comment was given in the Federal Register (78 FR 13015-13016, 02/26/2013..., Kleberg and Bee Counties, Texas, within and adjacent to the Corpus Christi Customs and Border...

  18. Electrical activity of corpus cavernosum in vasculogenic and non-vasculogenic erectile dysfunction.

    PubMed

    Atahan, O; Kayigil, O; Metin, A

    1997-12-01

    We aimed to compare the electrical activity of corpus cavernosum before and after intracavernous papaverine injection and to determine the blood lipid profile in vascular and non-vascular erectile dysfunction, and also to assess whether vascular pathology and abnormal blood lipid levels impair cavernosal smooth-muscle relaxation. We determined total cholesterol (TC), triglyceride (TG) and high-density lipoprotein (HDL) levels in peripheral and cavernosal blood in 39 patients with erectile dysfunction. Electromyography of the corpus cavernosum was performed before and after an intracavernous injection with 60 mg of papaverine in all patients. Thirty-nine impotent patients have been divided into two groups: vasculogenic erectile dysfunction (VED) and non-vasculogenic erectile dysfunction (NVED), according to colour Doppler ultrasonic flowmetry, dynamic infusion cavernosometry and the pressure difference between the brachial arterial systolic pressure and cavernosal arterial systolic pressure measurements. Biochemical values and amplitude changes were compared in both groups. The TC level was higher in both peripheral and cavernosal samples of the VED group than in the NVED group (p = 0.000), with no differences between peripheral and cavernosal blood levels within the same groups (p > 0.05). There were no significant changes in TG and HDL levels in any of the groups (p > 0.05). The mean amplitude differences before and after papaverine injection (delta A) were found to be 2.05 +/- 0.78 microV in the VED group and 4.68 +/- 2.53 microV in the NVED group, showing that the relaxation response to papaverine was more significant in the NVED than in the VED group (p = 0.003). The moderate decreases in the amplitude of electrical activity of corpus cavernosum and the higher TC levels found in the VED group can be accepted as the parameters of impairment in the relaxation of corpus cavernosum, showing the role of hypercholesterolaemia and vascular pathologies in erectile

  19. BioCreative V CDR task corpus: a resource for chemical disease relation extraction.

    PubMed

    Li, Jiao; Sun, Yueping; Johnson, Robin J; Sciaky, Daniela; Wei, Chih-Hsuan; Leaman, Robert; Davis, Allan Peter; Mattingly, Carolyn J; Wiegers, Thomas C; Lu, Zhiyong

    2016-01-01

    Community-run, formal evaluations and manually annotated text corpora are critically important for advancing biomedical text-mining research. Recently in BioCreative V, a new challenge was organized for the tasks of disease named entity recognition (DNER) and chemical-induced disease (CID) relation extraction. Given the nature of both tasks, a test collection is required to contain both disease/chemical annotations and relation annotations in the same set of articles. Despite previous efforts in biomedical corpus construction, none was found to be sufficient for the task. Thus, we developed our own corpus called BC5CDR during the challenge by inviting a team of Medical Subject Headings (MeSH) indexers for disease/chemical entity annotation and Comparative Toxicogenomics Database (CTD) curators for CID relation annotation. To ensure high annotation quality and productivity, detailed annotation guidelines and automatic annotation tools were provided. The resulting BC5CDR corpus consists of 1500 PubMed articles with 4409 annotated chemicals, 5818 diseases and 3116 chemical-disease interactions. Each entity annotation includes both the mention text spans and normalized concept identifiers, using MeSH as the controlled vocabulary. To ensure accuracy, the entities were first captured independently by two annotators followed by a consensus annotation: The average inter-annotator agreement (IAA) scores were 87.49% and 96.05% for the disease and chemicals, respectively, in the test set according to the Jaccard similarity coefficient. Our corpus was successfully used for the BioCreative V challenge tasks and should serve as a valuable resource for the text-mining research community.Database URL: http://www.biocreative.org/tasks/biocreative-v/track-3-cdr/. PMID:27161011

  20. BioCreative V CDR task corpus: a resource for chemical disease relation extraction

    PubMed Central

    Li, Jiao; Sun, Yueping; Johnson, Robin J.; Sciaky, Daniela; Wei, Chih-Hsuan; Leaman, Robert; Davis, Allan Peter; Mattingly, Carolyn J.; Wiegers, Thomas C.; Lu, Zhiyong

    2016-01-01

    Community-run, formal evaluations and manually annotated text corpora are critically important for advancing biomedical text-mining research. Recently in BioCreative V, a new challenge was organized for the tasks of disease named entity recognition (DNER) and chemical-induced disease (CID) relation extraction. Given the nature of both tasks, a test collection is required to contain both disease/chemical annotations and relation annotations in the same set of articles. Despite previous efforts in biomedical corpus construction, none was found to be sufficient for the task. Thus, we developed our own corpus called BC5CDR during the challenge by inviting a team of Medical Subject Headings (MeSH) indexers for disease/chemical entity annotation and Comparative Toxicogenomics Database (CTD) curators for CID relation annotation. To ensure high annotation quality and productivity, detailed annotation guidelines and automatic annotation tools were provided. The resulting BC5CDR corpus consists of 1500 PubMed articles with 4409 annotated chemicals, 5818 diseases and 3116 chemical-disease interactions. Each entity annotation includes both the mention text spans and normalized concept identifiers, using MeSH as the controlled vocabulary. To ensure accuracy, the entities were first captured independently by two annotators followed by a consensus annotation: The average inter-annotator agreement (IAA) scores were 87.49% and 96.05% for the disease and chemicals, respectively, in the test set according to the Jaccard similarity coefficient. Our corpus was successfully used for the BioCreative V challenge tasks and should serve as a valuable resource for the text-mining research community. Database URL: http://www.biocreative.org/tasks/biocreative-v/track-3-cdr/ PMID:27161011