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Sample records for abnormal corpus callosum

  1. Associated brain abnormalities in patients with corpus callosum anomalies.

    PubMed

    Tekgül, H; Dizdarer, G; Yalman, O; Sener, N; Yünten, N; Tütüncüoğlu, S

    1999-01-01

    Forty-nine patients with corpus callosum (CC) anomalies were evaluated in terms of the clinical features and magnetic resonance imaging (MRI) findings. CC anomalies were classified as CC agenesis: 6 (12%), CC hypogenesis: 5 (10%), and CC hypoplasia: 38 (78%). In the CC hypoplasia group the mean value of the genu thickness of the CC was 0.29 +/- 0.1 cm, which was less than the normal value of the age-matched normal children (normal range: 0.6-1.2 cm). The associated brain abnormalities were in five distinct groups: gray matter abnormalities, white matter abnormalities, midline brain structure defects, cortical atrophy, and encephalomalacia. There was no uniformity for the clinical spectrum of CC anomalies. Microcephaly, developmental delay and seizures were the prominent findings in patients. The clinical features were more severe in cases with associated brain anomalies.

  2. Clinical manifestations in children and adolescents with corpus callosum abnormalities.

    PubMed

    Margari, Lucia; Palumbi, Roberto; Campa, Maria Gloria; Operto, Francesca Felicia; Buttiglione, Maura; Craig, Francesco; Matricardi, Sara; Verrotti, Alberto

    2016-10-01

    Corpus callosum abnormality (CCA) outcomes are quite unpredictable and variable, from asymptomatic forms to mild or severe neurodevelopment disorders. The aim of this study was to examine clinical outcomes in CCA patients. The study included 61 children and adolescents in whom brain magnetic resonance imaging (MRI) scans showed CCA, isolated or associated to other central nervous system lesions. All patients underwent anamnesis, physical and neurological examination, routine laboratory tests, electroencephalogram (EEG), and MRI scans. In all participants, the intelligence quotient (IQ) was determined. We divided the participants into two subgroups: the first subgroup included patients with an isolated CCA, and the second subgroup included patients with CCA associated with extra-callosal brain lesions (complex CCA). We found that CCA were associated with elevated frequency to intellectual disability (ID), other neurodevelopment disorders, epilepsy, and isolated EEG anomalies. Mild ID (p = 0.003) was more frequent in the isolated subgroup, while epilepsy (p = 0.036) and pre-perinatal risk factors (p = 0.023) were more frequent in the complex CCA subgroup. Although the role of the CC in the interhemispheric communication is known, neurological and neurodevelopment outcomes of CCA are extremely variable and unpredictable. The presence of extra-callosal brain anomalies is one of the major prognostic factor, and probably, they have an important impact on the clinical outcome.

  3. 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…

  4. 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

  5. Bilingual corpus callosum variability.

    PubMed

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

    2004-04-01

    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 compared to monolingual individuals. The main interpretation of this finding is that the precentral gyrus is involved in bilingual faculty adaptation assuming a role consistent with the somatotopical input to areas dedicated to the mouth, and input to association tracts connecting the premotor and supplementary motor cortices. This paper discusses possible implications to neuroscientists, second language educators, and their students.

  6. Abnormality of the corpus callosum in coalmine gas explosion-related posttraumatic stress disorder.

    PubMed

    Zhang, Yang; Li, Huabing; Lang, Xu; Zhuo, Chuanjun; Qin, Wen; Zhang, Quan

    2015-01-01

    Abnormal corpus callosum (CC) has been reported in childhood trauma-related posttraumatic stress disorder (PTSD); however, the nature of white matter (WM) integrity alterations in the CC of young adult-onset PTSD patients is unknown. In this study, 14 victims of a coal mine gas explosion with PTSD and 23 matched coal miners without experiencing the coal mine explosion were enrolled. The differences in fractional anisotropy (FA) within 7 sub-regions of the CC were compared between the two groups. Compared to the controls, PTSD coal miners exhibited significantly reduced FA values in the anterior sub-regions of the CC (P < 0.05, Bonferroni-corrected), which mainly interconnect the bilateral frontal cortices. Our findings indicated that the anterior part of the CC was more severely impaired than the posterior part in young adult-onset PTSD, which suggested the patterns of CC impairment may depend on the developmental stage of the structure when the PTSD occurs.

  7. Abnormality of the Corpus Callosum in Coalmine Gas Explosion-Related Posttraumatic Stress Disorder

    PubMed Central

    Lang, Xu; Zhuo, Chuanjun; Qin, Wen; Zhang, Quan

    2015-01-01

    Abnormal corpus callosum (CC) has been reported in childhood trauma-related posttraumatic stress disorder (PTSD); however, the nature of white matter (WM) integrity alterations in the CC of young adult-onset PTSD patients is unknown. In this study, 14 victims of a coal mine gas explosion with PTSD and 23 matched coal miners without experiencing the coal mine explosion were enrolled. The differences in fractional anisotropy (FA) within 7 sub-regions of the CC were compared between the two groups. Compared to the controls, PTSD coal miners exhibited significantly reduced FA values in the anterior sub-regions of the CC (P < 0.05, Bonferroni-corrected), which mainly interconnect the bilateral frontal cortices. Our findings indicated that the anterior part of the CC was more severely impaired than the posterior part in young adult-onset PTSD, which suggested the patterns of CC impairment may depend on the developmental stage of the structure when the PTSD occurs. PMID:25799310

  8. 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…

  9. 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.

  10. 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

  11. Quantitative assessment of corpus callosum morphology in periventricular nodular heterotopia.

    PubMed

    Pardoe, Heath R; Mandelstam, Simone A; Hiess, Rebecca Kucharsky; Kuzniecky, Ruben I; Jackson, Graeme D

    2015-01-01

    We investigated systematic differences in corpus callosum morphology in periventricular nodular heterotopia (PVNH). Differences in corpus callosum mid-sagittal area and subregional area changes were measured using an automated software-based method. Heterotopic gray matter deposits were automatically labeled and compared with corpus callosum changes. The spatial pattern of corpus callosum changes were interpreted in the context of the characteristic anterior-posterior development of the corpus callosum in healthy individuals. Individuals with periventricular nodular heterotopia were imaged at the Melbourne Brain Center or as part of the multi-site Epilepsy Phenome Genome project. Whole brain T1 weighted MRI was acquired in cases (n=48) and controls (n=663). The corpus callosum was segmented on the mid-sagittal plane using the software "yuki". Heterotopic gray matter and intracranial brain volume was measured using Freesurfer. Differences in corpus callosum area and subregional areas were assessed, as well as the relationship between corpus callosum area and heterotopic GM volume. The anterior-posterior distribution of corpus callosum changes and heterotopic GM nodules were quantified using a novel metric and compared with each other. Corpus callosum area was reduced by 14% in PVNH (p=1.59×10(-9)). The magnitude of the effect was least in the genu (7% reduction) and greatest in the isthmus and splenium (26% reduction). Individuals with higher heterotopic GM volume had a smaller corpus callosum. Heterotopic GM volume was highest in posterior brain regions, however there was no linear relationship between the anterior-posterior position of corpus callosum changes and PVNH nodules. Reduced corpus callosum area is strongly associated with PVNH, and is probably associated with abnormal brain development in this neurological disorder. The primarily posterior corpus callosum changes may inform our understanding of the etiology of PVNH. Our results suggest that

  12. 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…

  13. Corpus Callosum MR Image Classification

    NASA Astrophysics Data System (ADS)

    Elsayed, A.; Coenen, F.; Jiang, C.; García-Fiñana, M.; Sluming, V.

    An approach to classifying Magnetic Resonance (MR) image data is described. The specific application is the classification of MRI scan data according to the nature of the corpus callosum, however the approach has more general applicability. A variation of the “spectral segmentation with multi-scale graph decomposition” mechanism is introduced. The result of the segmentation is stored in a quad-tree data structure to which a weighted variation (also developed by the authors) of the gSpan algorithm is applied to identify frequent sub-trees. As a result the images are expressed as a set frequent sub-trees. There may be a great many of these and thus a decision tree based feature reduction technique is applied before classification takes place. The results show that the proposed approach performs both efficiently and effectively, obtaining a classification accuracy of over 95% in the case of the given application.

  14. 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

  15. Corpus callosum volume and neurocognition in autism

    PubMed Central

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

    2011-01-01

    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 interhemispheric functioning. Participants with autism displayed reductions in total corpus callosum volume and in several of its subdivisions. Relationships were also observed between volumetric alterations and performance on several cognitive tests including the Tower of Hanoi test. These findings provide further evidence for volumetric alterations in the corpus callosum in autism, but warrant additional studies examining the relationship of this structure and specific measures of interhemispheric connectivity. PMID:19165587

  16. Corpus callosum volume and neurocognition in autism.

    PubMed

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

    2009-06-01

    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 interhemispheric functioning. Participants with autism displayed reductions in total corpus callosum volume and in several of its subdivisions. Relationships were also observed between volumetric alterations and performance on several cognitive tests including the Tower of Hanoi test. These findings provide further evidence for anatomical alterations in the corpus callosum in autism, but warrant additional studies examining the relationship of this structure and specific measures of interhemispheric connectivity. PMID:19165587

  17. Prenatal diagnosis of colpocephaly with absent corpus callosum.

    PubMed

    Ansary, Althaf; Manjunatha, C M; Ibhanesebhor, Samuel

    2015-02-01

    Colpocephaly is a rare abnormality of the brain, described as persistence of primitive foetal configuration of lateral ventricles. It has been found in association with several abnormalities of the brain. Herein we report a case of colpocephaly with absent corpus callosum, confirmed antenatally with foetal MRI following diagnostic suspicion based on absent septum pellucidum at prenatal sonography.

  18. 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

  19. Neural net simulation of the corpus callosum.

    PubMed

    Anninos, P A; Cook, N D

    1988-02-01

    The effects of simulated anatomical and physiological parameters were investigated in a "neural net" model, where two neural nets corresponding to two small patches of cerebral cortex were connected by a simulated "corpus callosum." The isolated neural nets have previously been shown to exhibit oscillatory activity similar to the raw EEG. By connecting the nets with fibers which have a specified percentage of inhibition and a specified percentage of homotopicity, the effects of such parameters on the cyclic activity of the nets were studied. It was found that, regardless of the inhibitory-excitatory nature of the simulated corpus callosum, the cyclic activity established in one hemisphere is more readily transferred to the contralateral hemisphere, the greater the percentage of homotopic callosal fibers. Learning was more rapid when the effect of the corpus callosum was primarily excitatory, but learning also took place over inhibitory or mixed callosal tracts. The simulation does not therefore resolve the issue of the predominant physiological effect of the corpus callosum, but does indicate that, given the assumptions of the simulation, "learning" can occur regardless of the percentage of excitatory or inhibitory fibers. It is noteworthy that homotopicity was more important for learning across an inhibitory tract than across an excitatory tract.

  20. Corpus callosum thickness in children: an MR pattern-recognition approach on the midsagittal image.

    PubMed

    Andronikou, Savvas; Pillay, Tanyia; Gabuza, Lungile; Mahomed, Nasreen; Naidoo, Jaishree; Hlabangana, Linda Tebogo; du Plessis, Vicci; Prabhu, Sanjay P

    2015-02-01

    Thickening of the corpus callosum is an important feature of development, whereas thinning of the corpus callosum can be the result of a number of diseases that affect development or cause destruction of the corpus callosum. Corpus callosum thickness reflects the volume of the hemispheres and responds to changes through direct effects or through Wallerian degeneration. It is therefore not only important to evaluate the morphology of the corpus callosum for congenital anomalies but also to evaluate the thickness of specific components or the whole corpus callosum in association with other findings. The goal of this pictorial review is raise awareness that the thickness of the corpus callosum can be a useful feature of pathology in pediatric central nervous system disease and must be considered in the context of the stage of development of a child. Thinning of the corpus callosum can be primary or secondary, and generalized or focal. Primary thinning is caused by abnormal or failed myelination related to the hypomyelinating leukoencephalopathies, metabolic disorders affecting white matter, and microcephaly. Secondary thinning of the corpus callosum can be caused by diffuse injury such as hypoxic-ischemic encephalopathy, human immunodeficiency virus (HIV) encephalopathy, hydrocephalus, dysmyelinating conditions and demyelinating conditions. Focal disturbance of formation or focal injury also causes localized thinning, e.g., callosal dysgenesis, metabolic disorders with localized effects, hypoglycemia, white matter injury of prematurity, HIV-related atrophy, infarction and vasculitis, trauma and toxins. The corpus callosum might be too thick because of a primary disorder in which the corpus callosum finding is essential to diagnosis; abnormal thickening can also be secondary to inflammation, infection and trauma.

  1. Agenesis of the corpus callosum. An autopsy study in fetuses.

    PubMed

    Kidron, Debora; Shapira, Daniel; Ben Sira, Liat; Malinger, Gustavo; Lev, Dorit; Cioca, Andreea; Sharony, Reuven; Lerman Sagie, Tally

    2016-02-01

    Agenesis of the corpus callosum is currently diagnosed prenatally with ultrasound and MRI. While the diagnostic aspects of callosal defects are widely addressed, anatomo-histological data from fetal autopsies are sparse. Callosal defects were present in 50 fetal autopsies. Four distinct groups of complete, partial, hypoplastic, and mixed defects were determined by the gross and histologic details of the corpus callosum. These details helped to rule out other midline defects such as holoprosencephaly. Additional autopsy findings enabled specific diagnoses and suggested etiopathogeneses. Hypoplastic and mixed defects were associated with more abnormalities of the cerebral hemispheres and internal organs. The four groups did not differ according to gender, external dysmorphism, or cerebellar and brainstem anomalies. Defects were classified as syndromic (68 %), encephaloclastic (8 %), undetermined (14 %), or isolated (10 %) based on the autopsy findings. Isolated agenesis of the corpus callosum was diagnosed in only 10 % of the cases in this series, compared to higher numbers diagnosed by prenatal ultrasonography and MRI. Therefore, the autopsy, through its detailed, careful evaluation of external, as well as gross and histological internal features, can elucidate the etiopathogenesis of agenesis of the corpus callosum and suggest specific diagnoses which cannot be ascertained by prenatal imaging. PMID:26573426

  2. Agenesis of the corpus callosum. An autopsy study in fetuses.

    PubMed

    Kidron, Debora; Shapira, Daniel; Ben Sira, Liat; Malinger, Gustavo; Lev, Dorit; Cioca, Andreea; Sharony, Reuven; Lerman Sagie, Tally

    2016-02-01

    Agenesis of the corpus callosum is currently diagnosed prenatally with ultrasound and MRI. While the diagnostic aspects of callosal defects are widely addressed, anatomo-histological data from fetal autopsies are sparse. Callosal defects were present in 50 fetal autopsies. Four distinct groups of complete, partial, hypoplastic, and mixed defects were determined by the gross and histologic details of the corpus callosum. These details helped to rule out other midline defects such as holoprosencephaly. Additional autopsy findings enabled specific diagnoses and suggested etiopathogeneses. Hypoplastic and mixed defects were associated with more abnormalities of the cerebral hemispheres and internal organs. The four groups did not differ according to gender, external dysmorphism, or cerebellar and brainstem anomalies. Defects were classified as syndromic (68 %), encephaloclastic (8 %), undetermined (14 %), or isolated (10 %) based on the autopsy findings. Isolated agenesis of the corpus callosum was diagnosed in only 10 % of the cases in this series, compared to higher numbers diagnosed by prenatal ultrasonography and MRI. Therefore, the autopsy, through its detailed, careful evaluation of external, as well as gross and histological internal features, can elucidate the etiopathogenesis of agenesis of the corpus callosum and suggest specific diagnoses which cannot be ascertained by prenatal imaging.

  3. 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…

  4. Agenesis of the Corpus Callosum and Generalized Epilepsy.

    PubMed

    Ilik, Faik; Bilgilisoy, Ugur T

    2015-07-01

    The corpus callosum is the main band of interhemispheric axonal fibers in the human brain. Corpus callosum agenesis has widely varying symptoms, mainly associated with epilepsy, cognitive failure, and different neuropsychiatric disorders. Our case of corpus callosum agenesis includes eyelid myoclonia with absences. In the literature, there is no reported case of this combination. We report this case because it is rare, and relevant for the understanding of interhemispheric communications, based on our electrophysiological findings.

  5. Regional Microstructural and Volumetric Magnetic Resonance Imaging (MRI) Abnormalities in the Corpus Callosum of Neonates With Congenital Heart Defect Undergoing Cardiac Surgery.

    PubMed

    Hagmann, Cornelia; Singer, Jitka; Latal, Beatrice; Knirsch, Walter; Makki, Malek

    2016-03-01

    The purpose of the study is to investigate the structural development of the corpus callosum in term neonates with congenital heart defect before and after surgery using diffusion tensor imaging and 3-dimensional T1-weighted magnetic resonance imaging (MRI). We compared parallel and radial diffusions, apparent diffusion coefficient (ADC), fractional anisotropy, and volume of 5 substructures of the corpus callosum: genu, rostral body, body, isthmus, and splenium. Compared to healthy controls, we found a significantly lower volume of the splenium and total corpus callosum and a higher radial diffusion and lower fractional anisotropy in the splenium of patients presurgery; a lower volume in all substructures in the postsurgery group; higher radial diffusion in the rostral body, body, and splenium; and a higher apparent diffusion coefficient in the splenium of postsurgery patients. Similar fractional anisotropy changes in congenital heart defect patients were reported in preterm infants. Our findings in apparent diffusion coefficient in the splenium of these patients (pre and postsurgery) are comparable to findings in preterm neonates with psychomotor delay. Delayed maturation of the isthmus was also reported in preterm infants.

  6. Thickness profile generation for the corpus callosum using Laplace's equation.

    PubMed

    Adamson, Christopher L; Wood, Amanda G; Chen, Jian; Barton, Sarah; Reutens, David C; Pantelis, Christos; Velakoulis, Dennis; Walterfang, Mark

    2011-12-01

    The corpus callosum facilitates communication between the cerebral hemispheres. Morphological abnormalities of the corpus callosum have been identified in numerous psychiatric and neurological disorders. To quantitatively analyze the thickness profile of the corpus callosum, we adapted an automatic thickness measurement method, which was originally used on magnetic resonance (MR) images of the cerebral cortex (Hutton et al. [2008]: NeuroImage 40:1701-10; Jones et al. [2002]: Hum Brain Mapp 11:12-32; Schmitt and Böhme [2002]: NeuroImage 16:1103-9; Yezzi and Prince [2003]: IEEE Trans Med Imaging 22:1332-9), to MR images of the corpus callosum. The thickness model was derived by computing a solution to Laplace's equation evaluated on callosal voxels. The streamlines from this solution form non-overlapping, cross-sectional contours the lengths of which are modeled as the callosal thickness. Apart from the semi-automated segmentation and endpoint selection procedures, the method is fully automated, robust, and reproducible. We compared the Laplace method with the orthogonal projection technique previously published (Walterfang et al. [2009a]: Psych Res Neuroimaging 173:77-82; Walterfang et al. [2008a]: Br J Psychiatry 192:429-34; Walterfang et al. [2008b]: Schizophr Res 103:1-10) on a cohort of 296 subjects, composed of 86 patients with chronic schizophrenia (CSZ), 110 individuals with first-episode psychosis, 100 individuals at ultra-high risk for psychosis (UHR; 27 of whom later developed psychosis, UHR-P, and 73 who did not, UHR-NP), and 55 control subjects (CTL). We report similar patterns of statistically significant differences in regional callosal thickness with respect to the comparisons CSZ vs. CTL, UHR vs. CTL, UHR-P vs. UHR-NP, and UHR vs. CTL.

  7. Agenesis of the corpus callosum and autism: a comprehensive comparison.

    PubMed

    Paul, Lynn K; Corsello, Christina; Kennedy, Daniel P; Adolphs, Ralph

    2014-06-01

    The corpus callosum, with its ∼200 million axons, remains enigmatic in its contribution to cognition and behaviour. Agenesis of the corpus callosum is a congenital condition in which the corpus callosum fails to develop; such individuals exhibit localized deficits in non-literal language comprehension, humour, theory of mind and social reasoning. These findings together with parent reports suggest that behavioural and cognitive impairments in subjects with callosal agenesis may overlap with the profile of autism spectrum disorders, particularly with respect to impairments in social interaction and communication. To provide a comprehensive test of this hypothesis, we directly compared a group of 26 adults with callosal agenesis to a group of 28 adults with a diagnosis of autism spectrum disorder but no neurological abnormality. All participants had full-scale intelligence quotient scores >78 and groups were matched on age, handedness, and gender ratio. Using the Autism Diagnostic Observation Schedule together with current clinical presentation to assess autistic symptomatology, we found that 8/26 (about a third) of agenesis subjects presented with autism. However, more formal diagnosis additionally involving recollective parent-report measures regarding childhood behaviour showed that only 3/22 met complete formal criteria for an autism spectrum disorder (parent reports were unavailable for four subjects). We found no relationship between intelligence quotient and autism symptomatology in callosal agenesis, nor evidence that the presence of any residual corpus callosum differentiated those who exhibited current autism spectrum symptoms from those who did not. Relative to the autism spectrum comparison group, parent ratings of childhood behaviour indicated children with agenesis were less likely to meet diagnostic criteria for autism, even for those who met autism spectrum criteria as adults, and even though there was no group difference in parent report of current

  8. Educational Implications for Agenesis of the Corpus Callosum.

    ERIC Educational Resources Information Center

    Ritter, Shirley A.

    This case study evaluates the case of a 20-year-old young Australian adult born with agenesis of the corpus callosum, the area of the brain uniting the hemispheres. Deficits commonly associated with agenesis of the corpus callosum are mental retardation, motor involvement, seizure activity, and lateral transfer difficulties. The report: (1)…

  9. Corpus callosum involvement and postoperative outcomes of patients with gliomas.

    PubMed

    Chen, Ko-Ting; Wu, Tai-Wei Erich; Chuang, Chi-Cheng; Hsu, Yung-Hsin; Hsu, Peng-Wei; Huang, Yin-Cheng; Lin, Tzu-Kang; Chang, Chen-Nen; Lee, Shih-Tseng; Wu, Chieh-Tsai; Tseng, Chen-Kan; Wang, Chun-Chieh; Pai, Ping-Ching; Wei, Kuo-Chen; Chen, Pin-Yuan

    2015-09-01

    Corpus callosum involvement is associated with poorer survival in high grade glioma (HGG), but the prognostic value in low grade glioma (LGG) is unclear. To determine the prognostic impact of corpus callosum involvement on progression free survival (PFS) and overall survival (OS) in HGG and LGG, the records of 233 glioma patients treated from 2008 to 2011 were retrospectively reviewed. Preoperative magnetic resonance (MR) images were used to identify corpus callosum involvement. Age, sex, preoperative Karnofsky performance scale, postoperative Eastern Cooperative Oncology Group (ECOG) score and extent of resection (EOR) were evaluated with respect to PFS and OS. The incidence of corpus callosum involvement was similar among HGG (14 %) and LGG (14.5 %). Univariate analysis revealed that PFS and OS were significantly shorter in both WHO grade II and grade IV glioma with corpus callosum involvement (both, p < 0.05). Multivariate analysis showed that grade II glioma with corpus callosum involvement have shorter PFS (p = 0.03), while EOR, instead of corpus callosum involvement (p = 0.16), was an independent factor associated with PFS in grade IV glioma (p < 0.05). Corpus callosum involvement was no longer significantly associated with OS after adjusting age, gender, EOR, preoperative and postoperative performance status (p = 0.16, 0.17 and 0.56 in grade II, III and IV gliomas, respectively). Corpus callosum involvement happened in both LGG and HGG, and is associated with lower EOR and higher postoperative ECOG score both in LGG and HGG. Corpus callosum involvement tends to be an independent prognostic factor for PFS in LGG, but not for OS in LGG or in HGG.

  10. Automatic recognition of corpus callosum from sagittal brain MR images

    NASA Astrophysics Data System (ADS)

    Lee, Chulhee; Unser, Michael A.; Ketter, Terence A.

    1995-08-01

    We propose a new method to find the corpus callosum from sagittal brain MR images automatically. First, we calculate the statistical characteristics of the corpus callosum and obtain shape information. The recognition algorithm consists of two stages: extracting regions satisfying the statistical characteristics (gray level distribtuions) of the corpus callosum, and finding a region matching the shape information. An innovative feature of the algorithm is that we adaptively relax the statistical requirement until we find a region matching the shape information. In order to match the shape information, we propose a new directed window region growing algorithm instead of using conventional contour matching. Experiments show promising results.

  11. Anatomy of corpus callosum in prenatally malnourished rats.

    PubMed

    Olivares, Ricardo; Morgan, Carlos; Pérez, Hernán; Hernández, Alejandro; Aboitiz, Francisco; Soto-Moyano, Rubén; Gil, Julio; Ortiz, Alexis; Flores, Osvaldo; Gimeno, Miguel; Laborda, Jesús

    2012-01-01

    The effect of prenatal malnutrition on the anatomy of the corpus callosum was assessed in adult rats (45-52 days old). In the prenatally malnourished animals we observed a significant reduction of the corpus callosum total area, partial areas, and perimeter, as compared with normal animals. In addition, the splenium of corpus callosum (posterior fifth) showed a significant decrease of fiber diameters in the myelinated fibers without changing density. There was also a significant decrease in diameter and a significant increase in density of unmyelinated fibers. Measurements of perimeter's fractal dimensions from sagittal sections of the brain and corpus callosum did not show significant differences between malnourished and control animals. These findings indicate that cortico-cortical connections are vulnerable to the prenatal malnutrition, and suggest this may affect interhemispheric conduction velocity, particularly in visual connections (splenium).

  12. 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…

  13. Corpus callosum: normal imaging appearance, variants and pathologic conditions.

    PubMed

    Battal, B; Kocaoglu, M; Akgun, V; Bulakbasi, N; Tayfun, C

    2010-12-01

    Various types of lesions can occur within the corpus callosum (CC) which is a white matter tract communicating corresponding regions of the cerebral hemispheres. Magnetic resonance imaging is the modality of choice for the evaluation of the CC. In addition, diffusion weighted imaging and diffusion tensor imaging can provide additional information about the CC. The aim of this study is to illustrate the imaging features of the corpus callosum and its pathologies. PMID:21199431

  14. 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

  15. How does the corpus callosum mediate interhemispheric transfer? A review.

    PubMed

    van der Knaap, Lisette J; van der Ham, Ineke J M

    2011-09-30

    The corpus callosum is the largest white matter structure in the human brain, connecting cortical regions of both hemispheres. Complete and partial callosotomies or callosal lesion studies have granted more insight into the function of the corpus callosum, namely the facilitation of communication between the cerebral hemispheres. How the corpus callosum mediates this information transfer is still a topic of debate. Some pose that the corpus callosum maintains independent processing between the two hemispheres, whereas others say that the corpus callosum shares information between hemispheres. These theories of inhibition and excitation are further explored by reviewing recent behavioural studies and morphological findings to gain more information about callosal function. Additional information regarding callosal function in relation to altered morphology and dysfunction in disorders is reviewed to add to the discussion of callosal involvement in interhemispheric transfer. Both the excitatory and inhibitory theories seem likely candidates to describe callosal function, however evidence also exists for both functions within the same corpus callosum. For future research it would be beneficial to investigate the functional role of the callosal sub regions to get a better understanding of function and use more appropriate experimental methods to determine functional connectivity when looking at interhemispheric transfer.

  16. Prosody meets syntax: the role of the corpus callosum.

    PubMed

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

    2010-09-01

    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 thought to have a primacy for the processing of suprasegmental prosodic information such as accentuation and boundary marking. A dynamic interplay between the hemispheres is assumed to allow for the timely coordination of both information types. The present event-related potential study investigated whether the anterior and/or posterior portion of the corpus callosum provide the crucial brain basis for the online interaction of syntactic and prosodic information. Patients with lesions in the anterior two-thirds of the corpus callosum connecting orbital and frontal structures, or the posterior third of the corpus callosum connecting temporal, parietal and occipital areas, as well as matched healthy controls, were tested in a paradigm that crossed syntactic and prosodic manipulations. An anterior negativity elicited by a mismatch between syntactically predicted phrase structure and prosodic intonation was analysed as a marker for syntax-prosody interaction. Healthy controls and patients with lesions in the anterior corpus callosum showed this anterior negativity demonstrating an intact interplay between syntax and prosody. No such effect was found in patients with lesions in the posterior corpus callosum, although they exhibited intact, prosody-independent syntactic processing comparable with healthy controls and patients with lesions in the anterior corpus callosum. These data support the interplay between the speech processing streams in the left and right hemispheres via the posterior portion of the corpus callosum, building the brain basis for the coordination and integration of local syntactic and prosodic features during

  17. Characterization of the corpus callosum in very preterm and full-term infants utilizing MRI

    PubMed Central

    Thompson, Deanne K.; Inder, Terrie E.; Faggian, Nathan; Johnston, Leigh; Warfield, Simon K.; Anderson, Peter J.; Doyle, Lex W.; Egan, Gary F.

    2011-01-01

    The corpus callosum is the largest white matter tract, important for interhemispheric communication. The aim of this study was to investigate and compare corpus callosum size, shape and diffusion characteristics in 106 very preterm infants and 22 full-term infants. Structural and diffusion magnetic resonance images were obtained at term equivalent. The corpus callosum was segmented, cross-sectional areas were calculated, and shape was analyzed. Fractional anisotropy, mean, axial and radial diffusivity measures were obtained from within the corpus callosum, with additional probabilistic tractography analysis. Very preterm infants had significantly reduced callosal cross sectional area compared with term infants (p=0.004), particularly for the mid-body and posterior sub-regions. Very preterm callosi were more circular (p=0.01). Fractional anisotropy was lower (p=0.007) and mean (p=0.006) and radial (p=0.001) diffusivity values were higher in very preterm infants’ callosi, particularly at the anterior and posterior ends. The volume of tracts originating from the corpus callosum was reduced in very preterm infants (p=0.001), particularly for anterior mid-body (p=0.01) and isthmus tracts (p=0.04). This study characterizes callosal size, shape and diffusion in typically developing infants at term equivalent age, and reports macro- and micro-structural abnormalities as a result of prematurity. PMID:21168519

  18. 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…

  19. 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.

  20. 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

  1. Agenesis of corpus callosum and frontotemporal dementia: a casual finding?

    PubMed

    Calabrò, Rocco Salvatore; Spadaro, Letteria; Marra, Angela; Balletta, Tina; Cammaroto, Simona; Bramanti, Placido

    2015-06-01

    Agenesis of corpus callosum (AgCC) is a congenital malformation characterized by total or partial absence of corpus callosum with a good neuropsychological profile. Frontotemporal dementia (FTD) is the third most common cause of cortical dementia, and it is characterized by alterations in personality and social relationship, often associated with deficits in attention, abstraction, planning, and problem solving. Herein, we report a case of a 73-year-old woman presenting with FTD associated with primary AgCC. The possible "causal or casual" relationship between these 2 different conditions should be investigated in large prospective studies.

  2. The Contribution of the Corpus Callosum to Language Lateralization

    PubMed Central

    Hinkley, Leighton B.N.; Marco, Elysa J.; Brown, Ethan G.; Bukshpun, Polina; Gold, Jacquelyn; Hill, Susanna; Findlay, Anne M.; Jeremy, Rita J.; Wakahiro, Mari L.; Barkovich, A. James; Mukherjee, Pratik

    2016-01-01

    The development of hemispheric lateralization for language is poorly understood. In one hypothesis, early asymmetric gene expression assigns language to the left hemisphere. In an alternate view, language is represented a priori in both hemispheres and lateralization emerges via cross-hemispheric communication through the corpus callosum. To address this second hypothesis, we capitalized on the high temporal and spatial resolution of magnetoencephalographic imaging to measure cortical activity during language processing, speech preparation, and speech execution in 25 participants with agenesis of the corpus callosum (AgCC) and 21 matched neurotypical individuals. In contrast to strongly lateralized left hemisphere activations for language in neurotypical controls, participants with complete or partial AgCC exhibited bilateral hemispheric activations in both auditory or visually driven language tasks, with complete AgCC participants showing significantly more right hemisphere activations than controls or than individuals with partial AgCC. In AgCC individuals, language laterality positively correlated with verbal IQ. These findings suggest that the corpus callosum helps to drive language lateralization. SIGNIFICANCE STATEMENT The role that corpus callosum development has on the hemispheric specialization of language is poorly understood. Here, we used magnetoencephalographic imaging during linguistic tests (verb generation, picture naming) to test for hemispheric dominance in patients with agenesis of the corpus callosum (AgCC) and found reduced laterality (i.e., greater likelihood of bilaterality or right hemisphere dominance) in this cohort compared with controls, especially in patients with complete agenesis. Laterality was positively correlated with behavioral measures of verbal intelligence. These findings provide support for the hypothesis that the callosum aids in functional specialization throughout neural development and that the loss of this mechanism

  3. 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…

  4. 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,…

  5. 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 =…

  6. Commissurotomy of the Corpus Callosum and the Remedial Reader.

    ERIC Educational Resources Information Center

    Albert, Elaine

    Testimony presented at a congressional hearing on illiteracy (March 1986) indicated that good readers use their myelinated corpus callosum fibers (which connect the left and right hemispheres of the brain) at millisecond speeds to coordinate the two brain hemispheres. Students taught using the whole-word recognition method (also called the…

  7. 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…

  8. Acute infarction of corpus callosum due to transient obstructive hydrocephalus.

    PubMed

    Kaymakamzade, Bahar; Eker, Amber

    2016-01-01

    Acute ischemia of the corpus callosum (CC) is not a well-known feature in patients with acute hydrocephalus. Herein, we describe a case with acute CC infarction due to another rare entity; transient obstructive hydrocephalus. A 66-year-old male was admitted with sudden onset right-sided hemiparesia. CT demonstrated a hematoma on the left basal ganglia with extension to all ventricles. The following day, the patient's neurological status progressed to coma and developed bilateral pyramidal signs. MRI demonstrated obstructive hydrocephalus and acute diffuse infarction accompanied by elevation of the CC. On the same day there was improvement in his neurological status with significant decrease in ventricular size and complete resolution of the clot in the third ventricle. The mechanism of signal abnormalities is probably related with the neural compression of the CC against the falx. Presumably, the clot causing obstruction in the third ventricle dissolved or decayed by the help of fibrinolytic activity of CSF, which was raised after IVH and caused spontaneous improvement of hydrocephalus. Bilateral neurological symptoms suggest diffuse axonal damage and normalization of the intracranial pressure should be performed on the early onset of clinical detorioration in order to prevent axonal injury. PMID:27375144

  9. Acute infarction of corpus callosum due to transient obstructive hydrocephalus.

    PubMed

    Kaymakamzade, Bahar; Eker, Amber

    2016-01-01

    Acute ischemia of the corpus callosum (CC) is not a well-known feature in patients with acute hydrocephalus. Herein, we describe a case with acute CC infarction due to another rare entity; transient obstructive hydrocephalus. A 66-year-old male was admitted with sudden onset right-sided hemiparesia. CT demonstrated a hematoma on the left basal ganglia with extension to all ventricles. The following day, the patient's neurological status progressed to coma and developed bilateral pyramidal signs. MRI demonstrated obstructive hydrocephalus and acute diffuse infarction accompanied by elevation of the CC. On the same day there was improvement in his neurological status with significant decrease in ventricular size and complete resolution of the clot in the third ventricle. The mechanism of signal abnormalities is probably related with the neural compression of the CC against the falx. Presumably, the clot causing obstruction in the third ventricle dissolved or decayed by the help of fibrinolytic activity of CSF, which was raised after IVH and caused spontaneous improvement of hydrocephalus. Bilateral neurological symptoms suggest diffuse axonal damage and normalization of the intracranial pressure should be performed on the early onset of clinical detorioration in order to prevent axonal injury.

  10. Autism traits in individuals with agenesis of the corpus callosum

    PubMed Central

    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 = 106) with the Autism Spectrum Quotient (AQ) and found that 45% of children, 35% of adolescents, and 18% of adults exceeded the predetermined autism-screening cut-off. Interestingly, performance on the AQ’s imagination domain was inversely correlated with magnetoencephalography measures of resting-state functional connectivity in the right superior temporal gyrus. Individuals with AgCC should be screened for ASD and disorders of the corpus callosum should be considered in autism diagnostic evaluations as well. PMID:23054201

  11. Cortical thickness in adults with agenesis of the corpus callosum.

    PubMed

    Beaulé, Vincent; Tremblay, Sara; Lafleur, Louis-Philippe; Tremblay, Sébastien; Lassonde, Maryse; Lepage, Jean-François; Théoret, Hugo

    2015-10-01

    Agenesis of the corpus callosum (AgCC) is a congenital malformation that can occur in isolation or in association with other neurological conditions. Although the behavioral manifestations associated with AgCC have been widely studied, the effects of complete absence of the corpus callosum (CC) on cerebral cortex anatomy are still not completely understood. In this study, cortical thickness in adults with complete AgCC was compared to a group of healthy controls. Results showed highly variable patterns of cortical thickness in AgCC individuals, with few areas showing significant and consistent alterations including primary visual cortex, primary somatosensory cortex and primary motor cortex. These results suggest relatively limited effects of AgCC on cortical morphology, which are mostly restricted to primary sensory and motor areas.

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

    PubMed

    Bassuk, Alexander G; Sherr, Elliott H

    2015-01-01

    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.

  13. In Vivo Longitudinal Monitoring of Changes in the Corpus Callosum Integrity During Disease Progression in a Mouse Model of Alzheimer's Disease.

    PubMed

    Kara, F; Höfling, C; Roßner, S; Schliebs, R; Van der Linden, A; Groot, H J M; Alia, A

    2015-01-01

    The corpus callosum is the largest commissural fiber connecting left and right hemisphere of the brain. Emerging evidence suggests that a variety of abnormalities detected in the microstructure of this white matter fiber can be an early event in Alzheimer's disease (AD) pathology. However, little is known about tissue characteristics of these abnormalities and how these abnormalities evolve during AD progression. In this study, we measured in vivo magnetic resonance transverse relaxation times (T2) to longitudinally monitor changes in tissue integrity and abnormalities related to myelination and demyelination processes in corpus callosum of AD mouse models. The most striking finding of our study was a significant elongation of T2 values in the corpus callosum at 10, 14, 16 and 18 months of age compared to age-matched wild-type mice. In contrast, the gray matter regions surrounding the corpus callosum, such as the cortex and hippocampus, showed a significant T2 decrease compared to wild-type mice. Histological analyses clearly revealed demyelination, gliosis and amyloid-plaque deposition in the corpus callosum. Our results suggest that demyelinating and inflammatory pathology may result in prolonged relaxation time during AD progression. To our knowledge, this is the first in vivo T2 study assessing the microstructural changes with age in the corpus callosum of the Tg2576 mouse model and it demonstrates the application of T2 measurement to noninvasively detect tissue integrity of the corpus callosum, which can be an early event in disease progression.

  14. 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

  15. 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

  16. 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

  17. Posterior polymorphous corneal dystrophy 3 is associated with agenesis and hypoplasia of the corpus callosum.

    PubMed

    Jang, Michelle S; Roldan, Ashley N; Frausto, Ricardo F; Aldave, Anthony J

    2014-07-01

    Posterior polymorphous corneal dystrophy (PPCD) is a dominantly inherited disorder of the corneal endothelium that has been associated with mutations in the zinc-finger E-box binding homeobox 1 gene (ZEB1) gene in approximately one-third of affected families. While the corneal dystrophies have traditionally been considered isolated disorders of the corneal endothelium, we have recently identified two cases of maldevelopment of the corpus callosum in unrelated individuals with PPCD. The proband of the first family was diagnosed shortly after birth with agenesis of the corpus callosum and several other developmental abnormalities. Karyotype, FISH and whole genome copy number variant analyses were normal. She was subsequently diagnosed with PPCD, prompting screening of the ZEB1 gene, which identified a novel deletion (c.449delG; p.(Gly150Alafs*36)) present in the heterozygous state that was not identified in either unaffected parent. The proband of the second family was diagnosed several months after birth with thinning of the corpus callosum and PPCD. Whole genome copy number variant analysis revealed a 1.79 Mb duplication of 17q12 in the proband and her father and brother, neither of whom had PPCD. ZEB1 sequencing identified a novel deletion (c.1913-1914delCA; p.(Ser638Cysfs*5)) present in the heterozygous state, which was also identified in the proband's affected mother. Thus, we report the first two cases of the association of PPCD with a developmental abnormality of the brain, in this case maldevelopment of the corpus callosum.

  18. Lesions of the corpus callosum and other commissural fibers: diffusion tensor studies.

    PubMed

    Filippi, Christopher G; Cauley, Keith A

    2014-10-01

    The corpus callosum is the largest white matter tract in the brain, connecting the 2 hemispheres. The functions of the corpus callosum are many and varied, and lesions frequently cause only subtle clinical findings. The range of diseases that can affect the corpus callosum is vast and includes all potential white matter disease. The distribution of lesions in the corpus callosum is disease specific in only a few entities such as Susac syndrome and Marchiafava-Bignami disease. Group studies have found significant differences of diffusivity metrics in the corpus callosum in preterm infants, patients suffering seizure activity, and patients with early-onset Alzheimer's disease. Given the challenges that multiple orientation of fibers within the callosum presents, advanced postprocessing methods may be required to reveal ultrastructural disease.

  19. 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

  20. 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

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

    PubMed

    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

    2016-08-01

    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.

  2. 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

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

    PubMed Central

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

    2015-01-01

    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

  4. Organising white matter in a brain without corpus callosum fibres.

    PubMed

    Bénézit, Audrey; Hertz-Pannier, Lucie; Dehaene-Lambertz, Ghislaine; Monzalvo, Karla; Germanaud, David; Duclap, Delphine; Guevara, Pamela; Mangin, Jean-François; Poupon, Cyril; Moutard, Marie-Laure; Dubois, Jessica

    2015-02-01

    Isolated corpus callosum dysgenesis (CCD) is a congenital malformation which occurs during early development of the brain. In this study, we aimed to identify and describe its consequences beyond the lack of callosal fibres, on the morphology, microstructure and asymmetries of the main white matter bundles with diffusion imaging and fibre tractography. Seven children aged between 9 and 13 years old and seven age- and gender-matched control children were studied. First, we focused on bundles within the mesial region of the cerebral hemispheres: the corpus callosum, Probst bundles and cingulum which were selected using a conventional region-based approach. We demonstrated that the Probst bundles have a wider connectivity than the previously described rostrocaudal direction, and a microstructure rather distinct from the cingulum but relatively close to callosal remnant fibres. A sigmoid bundle was found in two partial ageneses. Second, the corticospinal tract, thalamic radiations and association bundles were extracted automatically via an atlas of adult white matter bundles to overcome bias resulting from a priori knowledge of the bundles' anatomical morphology and trajectory. Despite the lack of callosal fibres and the colpocephaly observed in CCD, all major white matter bundles were identified with a relatively normal morphology, and preserved microstructure (i.e. fractional anisotropy, mean diffusivity) and asymmetries. Consequently the bundles' organisation seems well conserved in brains with CCD. These results await further investigations with functional imaging before apprehending the cognition variability in children with isolated dysgenesis.

  5. A computerized approach for morphological analysis of the corpus callosum

    SciTech Connect

    Davatzikos, C.; Vaillant, M.; Letovsky, S.; Bryan, R.N.; Prince, J.L.; Resnick, S.M.

    1996-01-01

    A new technique for analyzing the morphology of the corpus callosum is presented, and it is applied to a group of elderly subjects. The proposed approach normalizes subject data into the Talairach space using an elastic deformation transformation. The properties of this transformation are used as a quantitative description of the callosal shape with respect to the Talairach atlas, which is treated as a standard. In particular, a deformation function measures the enlargement/shrinkage associated with this elastic deformation. Intersubject comparisons are made by comparing deformation functions. This technique was applied to eight male and eight female subjects. Based on the average deformation functions of each group, the posterior region of the female corpus callosum was found to be larger than its corresponding region in the males. The average callosal shape of each group was also found, demonstrating visually the callosal shape differences between the two groups in this sample. The proposed methodology utilizes the full resolution of the data, rather than relying on global descriptions such as area measurements. The application of this methodology to an elderly group indicated sex-related differences in the callosal shape and size. 29 refs., 16 figs.

  6. 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…

  7. Automated segmentation of the corpus callosum in midsagittal brain magnetic resonance images

    NASA Astrophysics Data System (ADS)

    Lee, Chulhee; Huh, Shin; Ketter, Terence A.; Unser, Michael A.

    2000-04-01

    We propose a new algorithm to find the corpus callosum automatically from midsagittal brain MR (magnetic resonance) images using the statistical characteristics and shape information of the corpus callosum. We first extract regions satisfying the statistical characteristics (gray level distributions) of the corpus callosum that have relatively high intensity values. Then we try to find a region matching the shape information of the corpus callosum. In order to match the shape information, we propose a new directed window region growing algorithm instead of using conventional contour matching. An innovative feature of the algorithm is that we adaptively relax the statistical requirement until we find a region matching the shape information. After the initial segmentation, a directed border path pruning algorithm is proposed in order to remove some undesired artifacts, especially on the top of the corpus callosum. The proposed algorithm was applied to over 120 images and provided promising results.

  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. 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.

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

    PubMed

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

    2013-10-01

    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.

  11. 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

  12. Impaired Levels of Gangliosides in the Corpus Callosum of Huntington Disease Animal Models

    PubMed Central

    Di Pardo, Alba; Amico, Enrico; Maglione, Vittorio

    2016-01-01

    Huntington Disease (HD) is a genetic neurodegenerative disorder characterized by broad types of cellular and molecular dysfunctions that may affect both neuronal and non-neuronal cell populations. Among all the molecular mechanisms underlying the complex pathogenesis of the disease, alteration of sphingolipids has been identified as one of the most important determinants in the last years. In the present study, besides the purpose of further confirming the evidence of perturbed metabolism of gangliosides GM1, GD1a, and GT1b the most abundant cerebral glycosphingolipids, in the striatal and cortical tissues of HD transgenic mice, we aimed to test the hypothesis that abnormal levels of these lipids may be found also in the corpus callosum white matter, a ganglioside-enriched brain region described being dysfunctional early in the disease. Semi-quantitative analysis of GM1, GD1a, and GT1b content indicated that ganglioside metabolism is a common feature in two different HD animal models (YAC128 and R6/2 mice) and importantly, demonstrated that levels of these gangliosides were significantly reduced in the corpus callosum white matter of both models starting from the early stages of the disease. Besides corroborating the evidence of aberrant ganglioside metabolism in HD, here, we found out for the first time, that ganglioside dysfunction is an early event in HD models and it may potentially represent a critical molecular change influencing the pathogenesis of the disease. PMID:27766070

  13. 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

  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. Viscoelasticity of brain corpus callosum in biaxial tension

    NASA Astrophysics Data System (ADS)

    Labus, Kevin M.; Puttlitz, Christian M.

    2016-11-01

    Computational models of the brain rely on accurate constitutive relationships to model the viscoelastic behavior of brain tissue. Current viscoelastic models have been derived from experiments conducted in a single direction at a time and therefore lack information on the effects of multiaxial loading. It is also unclear if the time-dependent behavior of brain tissue is dependent on either strain magnitude or the direction of loading when subjected to tensile stresses. Therefore, biaxial stress relaxation and cyclic experiments were conducted on corpus callosum tissue isolated from fresh ovine brains. Results demonstrated the relaxation behavior to be independent of strain magnitude, and a quasi-linear viscoelastic (QLV) model was able to accurately fit the experimental data. Also, an isotropic reduced relaxation tensor was sufficient to model the stress-relaxation in both the axonal and transverse directions. The QLV model was fitted to the averaged stress relaxation tests at five strain magnitudes while using the measured strain history from the experiments. The resulting model was able to accurately predict the stresses from cyclic tests at two strain magnitudes. In addition to deriving a constitutive model from the averaged experimental data, each specimen was fitted separately and the resulting distributions of the model parameters were reported and used in a probabilistic analysis to determine the probability distribution of model predictions and the sensitivity of the model to the variance of the parameters. These results can be used to improve the viscoelastic constitutive models used in computational studies of the brain.

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

    PubMed

    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 de novo 163 kb interstitial 1q44 microdeletion in a boy with thin corpus callosum, psychomotor delay and seizures.

    PubMed

    Selmer, Kaja K; Bryne, Einar; Rødningen, Olaug K; Fannemel, Madeleine

    2012-12-01

    The 1q44 deletion syndrome has shown to be a recognizable phenotype with developmental delay, short stature and corpus callosum abnormalities as relatively consistent features. However, the disorder is still clinically heterogeneous and a genotype-phenotype correlation has been challenging to establish. In particular, a delineation of a critical region for the corpus callosum development has turned out to be difficult, and many candidate genes have been proposed. We present here a patient boy with a clinical picture of the 1q44 deletion syndrome, including a thin corpus callosum, and a small de novo 1q44 deletion. The deletion spans a maximum of 163 kb, a region which only contains the two genes FAM36A and HNRNPU. This finding supports the previously suggested hypothesis that the HNRNPU is an essential gene to the development of corpus callosum. However, as patients with deletions outside this interval also have been reported to have corpus callosum abnormalities, other mechanisms are probably also involved. We also identified two conserved non-coding regions in the deleted region of the patient, and speculate that also other elements interfere with the complex interplay and spatiotemporal gene expression during embryonic development. PMID:22975012

  18. 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

  19. 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.

  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. 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

  3. 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

  4. A cascade of morphogenic signaling initiated by the meninges controls corpus callosum formation.

    PubMed

    Choe, Youngshik; Siegenthaler, Julie A; Pleasure, Samuel J

    2012-02-23

    The corpus callosum is the most prominent commissural connection between the cortical hemispheres, and numerous neurodevelopmental disorders are associated with callosal agenesis. By using mice either with meningeal overgrowth or selective loss of meninges, we have identified a cascade of morphogenic signals initiated by the meninges that regulates corpus callosum development. The meninges produce BMP7, an inhibitor of callosal axon outgrowth. This activity is overcome by the induction of expression of Wnt3 by the callosal pathfinding neurons, which antagonize the inhibitory effects of BMP7. Wnt3 expression in the cingulate callosal pathfinding axons is developmentally regulated by another BMP family member, GDF5, which is produced by the adjacent Cajal-Retzius neurons and turns on before outgrowth of the callosal axons. The effects of GDF5 are in turn under the control of a soluble GDF5 inhibitor, Dan, made by the meninges. Thus, the meninges and medial neocortex use a cascade of signals to regulate corpus callosum development.

  5. Alien hand syndrome following corpus callosum infarction: A case report and review of the literature

    PubMed Central

    Gao, Xiaoyu; Li, Bing; Chu, Wenzheng; Sun, Xuwen; Sun, Chunjuan

    2016-01-01

    Alien hand syndrome (AHS) is characterized by involuntary and autonomous activity of the affected limbs, and consists of the frontal, callosal and posterior AHS variants. The callosal subtype, resulting from damage to the corpus callosum, frequently features intermanual conflict. However, infarction of the corpus callosum is rare due to abundant blood supply. The present study reported a case of AHS (callosal subtype, in the right hand) caused by callosal infarction. Infarction of the left corpus callosum was confirmed with magnetic resonance imaging. In addition, magnetic resonance angiography and digital subtraction angiography examinations revealed multiple lesions in the feeding arteries. Subsequent to antiplatelet therapy for 2 weeks following admission, the patient gradually recovered. Furthermore, the current study reviewed 31 previously reported cases of AHS following callosal infarction in the literature.

  6. Alien hand syndrome following corpus callosum infarction: A case report and review of the literature

    PubMed Central

    Gao, Xiaoyu; Li, Bing; Chu, Wenzheng; Sun, Xuwen; Sun, Chunjuan

    2016-01-01

    Alien hand syndrome (AHS) is characterized by involuntary and autonomous activity of the affected limbs, and consists of the frontal, callosal and posterior AHS variants. The callosal subtype, resulting from damage to the corpus callosum, frequently features intermanual conflict. However, infarction of the corpus callosum is rare due to abundant blood supply. The present study reported a case of AHS (callosal subtype, in the right hand) caused by callosal infarction. Infarction of the left corpus callosum was confirmed with magnetic resonance imaging. In addition, magnetic resonance angiography and digital subtraction angiography examinations revealed multiple lesions in the feeding arteries. Subsequent to antiplatelet therapy for 2 weeks following admission, the patient gradually recovered. Furthermore, the current study reviewed 31 previously reported cases of AHS following callosal infarction in the literature. PMID:27698701

  7. Reversible cerebral periventricular white matter changes with corpus callosum involvement in acute toluene-poisoning.

    PubMed

    Lin, Chih-Ming; Liu, Chi-Kuang

    2015-01-01

    Substance poisoning, such as toluene intoxication, has seldom been reported in the relevant literature. The documented cerebral neuroimaging has mostly described reversible symmetrical white matter changes in both the cerebral and cerebellar hemispheres. This paper presents 2 patients with toluene poisoning, whose brain magnetic resonance imaging studies showed a similar picture that included extra involvement over the corpus callosum; however, such corpus callosum involvement has never been mentioned and is quite rare in the literature. We discussed the underlying neuropathological pathways in this article. Hopefully, these cases will provide first-line clinicians with some valuable information with regard to toluene intoxication and clinical neuroimaging presentations.

  8. 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…

  9. Orodental manifestations in cases with partial agenesis of corpus callosum-rare phenomena

    PubMed Central

    Bhambal, Annette M.; Bhambal, Ajay; Nair, Preeti; Bhambal, Sheela S.

    2015-01-01

    This article focuses on the associated signs and symptoms of patients with partial agenesis of the corpus callosum. The orodental manifestations of such cases have been given special weightage which will prove to be of great help to oral physician when encountered with such cases. Case details Two siblings, aged 14 and 16 years, reported with a chief complaint of severe crowding of teeth with mouth breathing habit. They were low birth-weight babies and had been born to non-consanguinous parents. The distinguishing features of these children were craniofacial abnormalities, delayed developmental milestones, mild mental retardation and abnormal gait. The nosological features and the clinical manifestations of this syndrome and the plausible autosomal recessive inheritance of this rare syndrome have been elicited. The diagnosis was based on characteristic phenotype, in particular striking craniofacial and skeletal abnormalities and neuroimaging. Conclusion It is a challenge for healthcare professionals to help these youths to maximize their potential as human beings and help them achieve a meaningful adulthood. On the other hand, diagnosing such cases can be a challenge to dentistry. A systematic protocol, if adhered, can lead to a more appropriate diagnosis. Managing such cases in a clinical setup involves a multispeciality and interdisciplinary approach. PMID:26258024

  10. 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

  11. 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…

  12. Corpus callosum size and diffusion tensor anisotropy in adolescents and adults with schizophrenia.

    PubMed

    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

    2015-03-30

    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.

  13. The indusium griseum and the longitudinal striae of the corpus callosum.

    PubMed

    Di Ieva, Antonio; Fathalla, Hussein; Cusimano, Michael D; Tschabitscher, Manfred

    2015-01-01

    In the eighteenth century, Lancisi described the indusium griseum (IG) and the longitudinal striae (LS) of the corpus callosum. The IG is a thin neuronal lamina above the corpus callosum, covered on each side of the midline by the medial and lateral LS. The medial LS (nerves of Lancisi) and lateral LS are two pairs of myelinated fiber bands found in the gray matter of the IG on the dorsal aspect of the corpus callosum. Embryologically, the IG and LS are dorsal remnants of the archicortex of the hippocampus and fornix and thus they are considered components of the limbic system. Recent studies using immunohistochemistry reported that acetylcholine, dopamine, noradrenaline, 5-hydroxytryptamine and GABA neurons innervate the IG. Newer imaging techniques, such as high field MRI and diffusion tensor imaging, provide new tools for studying these structures, whose true function remains still unclear. The present paper reviews the history of the discovery of the IG and LS of the corpus callosum, with a holistic overview on these interesting structures from the anatomical, embryological, neurochemical, radiological and clinical perspective.

  14. The Brain Connection: The Corpus Callosum is Larger in Left-Handers.

    ERIC Educational Resources Information Center

    Witelson, Sandra F.

    1985-01-01

    Discusses the neurobiological basis for functional specialization of the cerebral hemispheres, indicating that the size of the corpus callosum is correlated with the neurophysiological measure of hand preference. In postmortem examinations of 42 subjects there were no sex differences, but mixed-handers had significantly larger total areas of the…

  15. 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…

  16. Agenesis of the Corpus Callosum: Assessment and Remediation of School-Related Problems.

    ERIC Educational Resources Information Center

    Puente, Antonio, E.

    The paper examines three cases of children born with brain damage (absence of corpus callosum). Common problems (attentional, cognitive, visuo-motor, and motor deficits) are noted, and the impact of secondary emotional involvement is considered. Intervention approaches with two of the children are described as inconsistent and inadequate, while…

  17. 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.

  18. 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…

  19. Corpus Callosum Morphology in Attention Deficit-Hyperactivity Disorder: Morphometric Analysis of MRI.

    ERIC Educational Resources Information Center

    Hynd, George W.; And Others

    1991-01-01

    Morphometric analysis of magnetic resonance imaging scans revealed that, compared to nondisabled controls, the seven children with attention deficit hyperactivity disorder had a smaller corpus callosum. Results suggest that subtle differences may exist in the brains of these children and that deviations in normal corticogenesis may underlie the…

  20. 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…

  1. 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…

  2. 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…

  3. Agenesis of the corpus callosum associated with paroxysmal hypothermia: Shapiro's syndrome.

    PubMed

    Segeren, C M; Polderman, K H; Lips, P

    1997-01-01

    Spontaneous recurrent hypothermia and hyperhidrosis associated with agenesis of the corpus callosum was first described by Shapiro and Plum in 1967. Since then, several cases with similar symptoms (now known as Shapiro's syndrome or spontaneous periodic hypothermia) have been described. We report another case of this syndrome in a 21-year-old-man, and discuss possible pathogenetic mechanisms and therapeutic approaches. PMID:9038041

  4. 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

  5. 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.

  6. 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

  7. 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

  8. 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

  9. Non-surgical treatment of massive traumatic corpus callosum hematoma after blunt head injury: A case report.

    PubMed

    Elsayed, A; Elgamal, E; Elsayed, A A; Wasserberg, J; Kuncz, A

    2016-01-01

    Massive hematoma of the corpus callosum caused by blunt head trauma is an extremely rare lesion. Most frequent traumatic lesions involve the corpus callosum are diffuse axonal injuries. They might be associated with small hemorrhagic foci in the hemispheric and brain stem white matter, intraventricular hemorrhages, subarachnoid hemorrhages, traumatic lesions of the septum pellucidum and fornix. Many cases of corpus callosum injury present with permanent disconnection syndrome. We present a case of a 32-year-old female suffered blunt head trauma resulted in massive corpus callosum hematoma which was managed non-surgically. The patient initially had a reduced conscious level and symptoms of disconnection syndrome, and significant recovery was observed at 6 months follow up. PMID:27375150

  10. Corpus callosum area and brain volume in autism spectrum disorder: quantitative analysis of structural MRI from the ABIDE database.

    PubMed

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

    2015-10-01

    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 region. No difference in the corpus callosum area was found between ASD participants and healthy controls (ASD 598.53 ± 109 mm(2); control 596.82 ± 102 mm(2); p = 0.76). The ASD participants had increased intracranial volume (ASD 1,508,596 ± 170,505 mm(3); control 1,482,732 ± 150,873.5 mm(3); p = 0.042). No evidence was found for overall ASD differences in the corpus callosum subregions.

  11. Non-surgical treatment of massive traumatic corpus callosum hematoma after blunt head injury: A case report.

    PubMed

    Elsayed, A; Elgamal, E; Elsayed, A A; Wasserberg, J; Kuncz, A

    2016-01-01

    Massive hematoma of the corpus callosum caused by blunt head trauma is an extremely rare lesion. Most frequent traumatic lesions involve the corpus callosum are diffuse axonal injuries. They might be associated with small hemorrhagic foci in the hemispheric and brain stem white matter, intraventricular hemorrhages, subarachnoid hemorrhages, traumatic lesions of the septum pellucidum and fornix. Many cases of corpus callosum injury present with permanent disconnection syndrome. We present a case of a 32-year-old female suffered blunt head trauma resulted in massive corpus callosum hematoma which was managed non-surgically. The patient initially had a reduced conscious level and symptoms of disconnection syndrome, and significant recovery was observed at 6 months follow up.

  12. Contralateral targeting of the corpus callosum in normal and pathological brain function.

    PubMed

    Fenlon, Laura R; Richards, Linda J

    2015-05-01

    The corpus callosum connects the two cortical hemispheres of the mammalian brain and is susceptible to structural defects during development, which often result in significant neuropsychological dysfunction. To date, such individuals have been studied primarily with regards to the integrity of the callosal tract at the midline. However, the mechanisms regulating the contralateral targeting of the corpus callosum, after midline crossing has occurred, are less well understood. Recent evidence suggests that defects in contralateral targeting can occur in isolation from midline-tract malformations, and may have significant functional implications. We propose that contralateral targeting is a crucially important and relatively under-investigated event in callosal development, and that defects in this process may constitute an undiagnosed phenotype in several neurological disorders.

  13. Shape analysis of corpus callosum in phenylketonuria using a new 3D correspondence algorithm

    NASA Astrophysics Data System (ADS)

    He, Qing; Christ, Shawn E.; Karsch, Kevin; Peck, Dawn; Duan, Ye

    2010-03-01

    Statistical shape analysis of brain structures has gained increasing interest from neuroimaging community because it can precisely locate shape differences between healthy and pathological structures. The most difficult and crucial problem is establishing shape correspondence among individual 3D shapes. This paper proposes a new algorithm for 3D shape correspondence. A set of landmarks are sampled on a template shape, and initial correspondence is established between the template and the target shape based on the similarity of locations and normal directions. The landmarks on the target are then refined by iterative thin plate spline. The algorithm is simple and fast, and no spherical mapping is needed. We apply our method to the statistical shape analysis of the corpus callosum (CC) in phenylketonuria (PKU), and significant local shape differences between the patients and the controls are found in the most anterior and posterior aspects of the corpus callosum.

  14. Developmental changes in the corpus callosum from infancy to early adulthood: a structural magnetic resonance imaging study.

    PubMed

    Tanaka-Arakawa, Megumi M; Matsui, Mie; Tanaka, Chiaki; Uematsu, Akiko; Uda, Satoshi; Miura, Kayoko; Sakai, Tomoko; Noguchi, Kyo

    2015-01-01

    Previous research has reported on the development trajectory of the corpus callosum morphology. However, there have been only a few studies that have included data on infants. The goal of the present study was to examine the morphology of the corpus callosum in healthy participants of both sexes, from infancy to early adulthood. We sought to characterize normal development of the corpus callosum and possible sex differences in development. We performed a morphometric magnetic resonance imaging (MRI) study of 114 healthy individuals, aged 1 month to 25 years old, measuring the size of the corpus callosum. The corpus callosum was segmented into seven subareas of the rostrum, genu, rostral body, anterior midbody, posterior midbody, isthmus and splenium. Locally weighted regression analysis (LOESS) indicated significant non-linear age-related changes regardless of sex, particularly during the first few years of life. After this increase, curve slopes gradually became flat during adolescence and adulthood in both sexes. Age of local maximum for each subarea of the corpus callosum differed across the sexes. Ratios of total corpus callosum and genu, posterior midbody, as well as splenium to the whole brain were significantly higher in females compared with males. The present results demonstrate that the developmental trajectory of the corpus callosum during early life in healthy individuals is non-linear and dynamic. This pattern resembles that found for the cerebral cortex, further suggesting that this period plays a very important role in neural and functional development. In addition, developmental trajectories and changes in growth do show some sex differences.

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

    PubMed Central

    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

    2015-01-01

    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

  16. 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.

  17. Microstructural White Matter Changes in the Corpus Callosum of Young People with Bipolar Disorder: A Diffusion Tensor Imaging Study

    PubMed Central

    Lagopoulos, Jim; Hermens, Daniel F.; Hatton, Sean N.; Tobias-Webb, Juliette; Griffiths, Kristi; Naismith, Sharon L.; Scott, Elizabeth M.; Hickie, Ian B.

    2013-01-01

    To date, most studies of white matter changes in Bipolar Disorder (BD) have been conducted in older subjects and with well-established disorders. Studies of young people who are closer to their illness onset may help to identify core neurobiological characteristics and separate these from consequences of repeated illness episodes or prolonged treatment. Diffusion tensor imaging (DTI) was used to examine white matter microstructural changes in 58 young patients with BD (mean age 23 years; range 16–30 years) and 40 controls. Whole brain voxelwise measures of fractional anisotropy (FA), parallel diffusivity (λ//) and radial diffusivity (λ⊥) were calculated for all subjects. White matter microstructure differences (decreased FA corrected p<.05) were found between the patients with BD and controls in the genu, body and splenium of the corpus callosum as well as the superior and anterior corona radiata. In addition, significantly increased radial diffusivity (p<.01) was found in the BD group. Neuroimaging studies of young patients with BD may help to clarify neurodevelopmental aspects of the illness and for identifying biomarkers of disease onset and progression. Our findings provide evidence of microstructural white matter changes early in the course of illness within the corpus callosum and the nature of these changes suggest they are associated with abnormalities in the myelination of axons. PMID:23527101

  18. Functional topography of the corpus callosum investigated by DTI and fMRI

    PubMed Central

    Fabri, Mara; Pierpaoli, Chiara; Barbaresi, Paolo; Polonara, Gabriele

    2014-01-01

    This short review examines the most recent functional studies of the topographic organization of the human corpus callosum, the main interhemispheric commissure. After a brief description of its anatomy, development, microstructure, and function, it examines and discusses the latest findings obtained using diffusion tensor imaging (DTI) and tractography (DTT) and functional magnetic resonance imaging (fMRI), three recently developed imaging techniques that have significantly expanded and refined our knowledge of the commissure. While DTI and DTT have been providing insights into its microstructure, integrity and level of myelination, fMRI has been the key technique in documenting the activation of white matter fibers, particularly in the corpus callosum. By combining DTT and fMRI it has been possible to describe the trajectory of the callosal fibers interconnecting the primary olfactory, gustatory, motor, somatic sensory, auditory and visual cortices at sites where the activation elicited by peripheral stimulation was detected by fMRI. These studies have demonstrated the presence of callosal fiber tracts that cross the commissure at the level of the genu, body, and splenium, at sites showing fMRI activation. Altogether such findings lend further support to the notion that the corpus callosum displays a functional topographic organization that can be explored with fMRI. PMID:25550994

  19. 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

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

    PubMed

    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

    2015-08-18

    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.

  1. 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.

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

    PubMed

    Edwards, Timothy J; Sherr, Elliott H; Barkovich, A James; Richards, Linda J

    2014-06-01

    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.

  3. 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

  4. 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

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

    PubMed Central

    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

  6. 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

    2016-01-19

    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.

  7. Trisomy 8 syndrome owing to isodicentric 8p chromosomes: regional assignment of a presumptive gene involved in corpus callosum development.

    PubMed Central

    Digilio, M C; Giannotti, A; Floridia, G; Uccellatore, F; Mingarelli, R; Danesino, C; Dallapiccola, B; Zuffardi, O

    1994-01-01

    Two patients with trisomy 8 syndrome owing to an isodicentric 8p;8p chromosome are described. Case 1 had a 46,XX/46,XX,-8,+idic(8)(p23) karyotype while case 2, a male, had the same abnormal karyotype without evidence of mosaicism. In situ hybridisation, performed in case 1, showed that the isochromosome was asymmetrical. Agenesis of the corpus callosum (ACC), which is a feature of trisomy 8 syndrome, was found in both patients. Although ACC is associated with aneuploidies for different chromosomes, a review of published reports indicates that, when associated with chromosome 8, this defect is the result of duplication of a gene located within 8p21-pter. Molecular analysis in one of our patients led us to exclude the distal 23 Mb of 8p from this ACC region. Images PMID:8014974

  8. 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

  9. 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.

  10. Effects of prenatal irradiation on the development of cerebral cortex and corpus callosum of the mouse

    SciTech Connect

    Schmidt, S.L.; Lent, R.

    1987-10-08

    Defects of the cerebral cortex and corpus callosum of mice subjected prenatally to gamma irradiation were evaluated as a function of dose and of embryonic age at irradiation. Pregnant mice were exposed to a gamma source at 16, 17, and 19 days of gestation (E16, E17, and E19, respectively), with total doses of 2 Gy and 3 Gy, in order to produce brain defects on their progeny. At 60 postnatal days, the brains of the offspring were analyzed qualitatively and quantitatively and compared with those of nonirradiated animals. Mice irradiated at E16 were all acallosal. Those that were exposed to 2 Gy displayed an aberrant longitudinal bundle typical of other acallosals, but this was not the case in those irradiated with 3 Gy. The corpus callosum of animals irradiated at E17 with 3 Gy was pronouncedly hypotrophic, but milder effects were observed in the other groups. Quantitative analysis confirmed a dependence of callosal midsagittal area upon dose and age at irradiation, and, in addition, indicated an interaction between these variables. The neocortex of irradiated animals was hypotrophic: layers II-III were much more affected than layer V, and this was more affected than layer VI. Quantitative analysis indicated that this effect also depended on dose and age at irradiation and that it was due to a loss of cortical neurons. Furthermore, a positive correlation was found between the number of neurons within layers II-III, and V and the midsagittal area of the corpus callosum. Ectopic neurons were found in the white matter and in layer I of animals irradiated at E16 and E17, indicating that fetal exposure to ionizing radiation interfered with the migration of cortical neuroblasts.

  11. 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

  12. Corpus callosum size is highly heritable in humans, and may reflect distinct genetic influences on ventral and rostral regions.

    PubMed

    Woldehawariat, Girma; Martinez, Pedro E; Hauser, Peter; Hoover, David M; Drevets, Wayne W C; McMahon, Francis J

    2014-01-01

    Anatomical differences in the corpus callosum have been found in various psychiatric disorders, but data on the genetic contributions to these differences have been limited. The current study used morphometric MRI data to assess the heritability of corpus callosum size and the genetic correlations among anatomical sub-regions of the corpus callosum among individuals with and without mood disorders. The corpus callosum (CC) was manually segmented at the mid-sagittal plane in 42 women (healthy, n = 14; major depressive disorder, n = 15; bipolar disorder, n = 13) and their 86 child or adolescent offspring. Four anatomical sub-regions (CC-genu, CC2, CC3 and CC-splenium) and total CC were measured and analyzed. Heritability and genetic correlations were estimated using a variance components method, with adjustment for age, sex, diagnosis, and diagnosis x age, where appropriate. Significant heritability was found for several CC sub-regions (P<0.01), with estimated values ranging from 48% (splenium) to 67% (total CC). There were strong and significant genetic correlations among most sub regions. Correlations between the genu and mid-body, between the genu and total corpus callosum, and between anterior and mid body were all >90%, but no significant genetic correlations were detected between ventral and rostral regions in this sample. Genetic factors play an important role in corpus callosum size among individuals. Distinct genetic factors seem to be involved in caudal and rostral regions, consistent with the divergent functional specialization of these brain areas. PMID:24968245

  13. 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

  14. Early-life stress, corpus callosum development, hippocampal volumetrics, and anxious behavior in male nonhuman primates.

    PubMed

    Jackowski, Andrea; Perera, Tarique D; Abdallah, Chadi G; Garrido, Griselda; Tang, Cheuk Y; Martinez, Jose; Mathew, Sanjay J; Gorman, Jack M; Rosenblum, Leonard A; Smith, Eric L P; Dwork, Andrew J; Shungu, Dikoma C; Kaffman, Arie; Gelernter, Joel; Coplan, Jeremy D; Kaufman, Joan

    2011-04-30

    Male bonnet monkeys (Macaca radiata) were subjected to the variable foraging demand (VFD) early stress paradigm as infants, MRI scans were completed an average of 4 years later, and behavioral assessments of anxiety and ex-vivo corpus callosum (CC) measurements were made when animals were fully matured. VFD rearing was associated with smaller CC size, CC measurements were found to correlate with fearful behavior in adulthood, and ex-vivo CC assessments showed high consistency with earlier MRI measures. Region of interest (ROI) hippocampus and whole brain voxel-based morphometry assessments were also completed and VFD rearing was associated with reduced hippocampus and inferior and middle temporal gyri volumes. The animals were also characterized according to serotonin transporter genotype (5-HTTLPR), and the effect of genotype on imaging parameters was explored. The current findings highlight the importance of future research to better understand the effects of stress on brain development in multiple regions, including the corpus callosum, hippocampus, and other regions involved in emotion processing. Nonhuman primates provide a powerful model to unravel the mechanisms by which early stress and genetic makeup interact to produce long-term changes in brain development, stress reactivity, and risk for psychiatric disorders.

  15. 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.

  16. Corpus callosum analysis using MDL-based sequential models of shape and appearance

    NASA Astrophysics Data System (ADS)

    Stegmann, Mikkel B.; Davies, Rhodri H.; Ryberg, Charlotte

    2004-05-01

    This paper describes a method for automatically analysing and segmenting the corpus callosum from magnetic resonance images of the brain based on the widely used Active Appearance Models (AAMs) by Cootes et al. Extensions of the original method, which are designed to improve this specific case are proposed, but all remain applicable to other domain problems. The well-known multi-resolution AAM optimisation is extended to include sequential relaxations on texture resolution, model coverage and model parameter constraints. Fully unsupervised analysis is obtained by exploiting model parameter convergence limits and a maximum likelihood estimate of shape and pose. Further, the important problem of modelling object neighbourhood is addressed. Finally, we describe how correspondence across images is achieved by selecting the minimum description length (MDL) landmarks from a set of training boundaries using the recently proposed method of Davies et al. This MDL-approach ensures a unique parameterisation of corpus callosum contour variation, which is crucial for neurological studies that compare reference areas such as rostrum, splenium, et cetera. We present quantitative and qualitative results that show that the method produces accurate, robust and rapid segmentations in a cross sectional study of 17 subjects, establishing its feasibility as a fully automated clinical tool for analysis and segmentation.

  17. 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.

  18. Behavioral correlates of corpus callosum size: Anatomical/behavioral relationships vary across sex/handedness groups

    PubMed Central

    Welcome, Suzanne E.; Chiarello, Christine; Towler, Stephen; Halderman, Laura K.; Otto, Ronald; Leonard, Christiana M.

    2009-01-01

    There are substantial individual differences in the size and shape of the corpus callosum and such differences are thought to relate to behavioral lateralization. We report findings from a large scale investigation of relationships between brain anatomy and behavioral asymmetry on a battery of visual word recognition tasks. A sample of 200 individuals was divided into groups on the basis of sex and consistency of handedness. We investigated differences between sex/handedness groups in callosal area and relationships between callosal area and behavioral predictors. Sex/handedness groups did not show systematic differences in callosal area or behavioral asymmetry. However, the groups differed in the relationships between area of the corpus callosum and behavioral asymmetry. Among consistent-handed males, callosal area was negatively related to behavioral laterality. Among mixed-handed males and consistent-handed females, behavioral laterality was not predictive of callosal area. The most robust relationship was observed in mixed-handed females, in whom behavioral asymmetry was positively related to callosal area. Our study demonstrates the importance of considering brain/behavior relationships within sub-populations, as relationships between behavioral asymmetry and callosal anatomy varied across subject groups. PMID:19383501

  19. 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

  20. Endogenous testosterone concentration, mental rotation, and size of the corpus callosum in a sample of young Hungarian women.

    PubMed

    Karádi, Kázmér; Kállai, János; Kövér, Ferenc; Nemes, János; Makány, Tamás; Nagy, Ferenc

    2006-04-01

    In the present study brain laterality, hemispheric communication, and mental rotation performance were examined. A sample of 33 women were tested for a possible linear relationship of testosterone level and mental rotation with structural background of the brain. Subjects with a smaller splenial area of corpus callosum tended to have lower levels of testosterone (r =.37, p<.05). However, there were no significant differences in mean scores of mental rotation of object and hand between groups with high and low levels of testosterone. There was a significant difference in relative size of the 6th area (slice) of the corpus callosum between groups with good and poor scores on mental rotation of an object and also in relative size of the 4th and 5th slices of the corpus callosum between groups on mental rotation of the hand. The good and poor scorers' show different relations with the measures of the corpus. The mental rotation of hand was associated with the parietal areas of the corpus callosum, while the mental rotation of object was associated only with the occipital area. These observations suggest that higher testosterone levels may be associated with a larger splenial area, which represents an important connection between the parieto-occipitocortical areas involved in activation of mental images. Further srudy is encouraged.

  1. 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

  2. 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…

  3. The subventricular zone continues to generate corpus callosum and rostral migratory stream astroglia in normal adult mice.

    PubMed

    Sohn, Jiho; Orosco, Lori; Guo, Fuzheng; Chung, Seung-Hyuk; Bannerman, Peter; Mills Ko, Emily; Zarbalis, Kostas; Deng, Wenbin; Pleasure, David

    2015-03-01

    Astrocytes are the most abundant cells in the CNS, and have many essential functions, including maintenance of blood-brain barrier integrity, and CNS water, ion, and glutamate homeostasis. Mammalian astrogliogenesis has generally been considered to be completed soon after birth, and to be reactivated in later life only under pathological circumstances. Here, by using genetic fate-mapping, we demonstrate that new corpus callosum astrocytes are continuously generated from nestin(+) subventricular zone (SVZ) neural progenitor cells (NPCs) in normal adult mice. These nestin fate-mapped corpus callosum astrocytes are uniformly postmitotic, express glutamate receptors, and form aquaporin-4(+) perivascular endfeet. The entry of new astrocytes from the SVZ into the corpus callosum appears to be balanced by astroglial apoptosis, because overall numbers of corpus callosum astrocytes remain constant during normal adulthood. Nestin fate-mapped astrocytes also flow anteriorly from the SVZ in association with the rostral migratory stream, but do not penetrate into the deeper layers of the olfactory bulb. Production of new astrocytes from nestin(+) NPCs is absent in the normal adult cortex, striatum, and spinal cord. Our study is the first to demonstrate ongoing SVZ astrogliogenesis in the normal adult mammalian forebrain.

  4. [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.

  5. Chiari type 1 malformation, corpus callosum agenesis and patent craniopharyngeal canal in an 11-year-old boy.

    PubMed

    Tijssen, Maud Pm; Poretti, Andrea; Huisman, Thierry Agm

    2016-10-01

    We describe the neuroimaging findings of an 11-year-old boy who presented with mild occipital headache and precocious puberty. This child was found to have a combination of various midline anomalies including a Chiari type 1 malformation, corpus callosum agenesis and patent craniopharyngeal canal with adjacent intracranial dermoid cyst.

  6. [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

  7. Neurotransmitter receptors and voltage-dependent Ca2+ channels encoded by mRNA from the adult corpus callosum.

    PubMed

    Matute, C; Miledi, R

    1993-04-15

    The presence of mRNAs encoding neurotransmitter receptors and voltage-gated channels in the adult human and bovine corpus callosum was investigated using Xenopus oocytes. Oocytes injected with mRNA extracted from the corpus callosum expressed functional receptors to glutamate, acetylcholine, and serotonin, and also voltage-operated Ca2+ channels, all with similar properties in the two species studied. Acetylcholine and serotonin elicited oscillatory Cl- currents due to activation of the inositol phosphate-Ca2+ receptor-channel coupling system. Glutamate and its analogs N-methyl-D-aspartate (NMDA), kainate, quisqualate, and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) induced smooth currents. The non-NMDA responses showed a strong inward rectification at positive potentials and were potently blocked by 6,7-dinitroquinoxaline-2,3-dione, as observed for the AMPA/kainate glutamate receptors GLUR1 and GLUR3. Furthermore, in situ hybridization experiments showed that GLUR1 and GLUR3 mRNAs are present in corpus callosum cells that were labeled with antiserum to glial fibrillary acid protein and that, in primary cell cultures, had the morphology of type 2 astrocytes. These results indicate that glial cells in the adult corpus callosum possess mRNA encoding functional neurotransmitter receptors and Ca2+ channels. These molecules may provide a mechanism for glial-neuronal interactions. PMID:7682696

  8. Correlation between Corpus Callosum Sub-Segmental Area and Cognitive Processes in School-Age Children

    PubMed Central

    Moreno, Martha Beatriz; Concha, Luis; González-Santos, Leopoldo; Ortiz, Juan Jose; Barrios, Fernando Alejandro

    2014-01-01

    We assessed the relationship between structural characteristics (area) and microstructure (apparent diffusion coefficient; ADC) of the corpus callosum (CC) in 57 healthy children aged 7.0 to 9.1 years, with diverse cognitive and academic abilities as well as executive functions evaluated with a neuropsychological battery for children. The CC was manually delineated and sub-segmented into six regions, and their ADC and area were measured. There were no significant differences between genders in the callosal region area or in ADC. The CC area and ADC, mainly of anterior regions, correlated with different cognitive abilities for each gender. Our results suggest that the relationship between cognitive abilities and CC characteristics is different between girls and boys and between the anterior and posterior regions of the CC. Furthermore, these findings strenghten the idea that regardless of the different interhemispheric connectivity schemes per gender, the results of cognitive tasks are very similar for girls and boys throughout childhood. PMID:25170897

  9. 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

  10. 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.

  11. A two-year longitudinal MRI study of the corpus callosum in autism.

    PubMed

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

    2012-11-01

    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 baseline and 2-year follow-up. Persistent reductions in total CC volume were observed in participants with autism relative to controls. Only the rostral body subdivision showed a normalization of size over time. Persistent reductions are consistent with the diagnostic stability and life-long impairment observed in many individuals with autism. Multi-modal imaging studies are needed to identify specific fiber tracks contributing to CC reductions.

  12. 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.

  13. 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

  14. Reduced fractional anisotropy in the anterior corpus callosum is associated with reduced speech fluency in persistent developmental stuttering.

    PubMed

    Civier, Oren; Kronfeld-Duenias, Vered; Amir, Ofer; Ezrati-Vinacour, Ruth; Ben-Shachar, Michal

    2015-04-01

    Developmental stuttering is a speech disorder that severely limits one's ability to communicate. White matter anomalies were reported in stuttering, but their functional significance is unclear. We analyzed the relation between white matter properties and speech fluency in adults who stutter (AWS). We used diffusion tensor imaging with tract-based spatial statistics, and examined group differences as well as correlations with behavioral fluency measures. We detected a region in the anterior corpus callosum with significantly lower fractional anisotropy in AWS relative to controls. Within the AWS group, reduced anisotropy in that region is associated with reduced fluency. A statistically significant interaction was found between group and age in two additional regions: the left Rolandic operculum and the left posterior corpus callosum. Our findings suggest that anterior callosal anomaly in stuttering may represent a maladaptive reduction in interhemispheric inhibition, possibly leading to a disadvantageous recruitment of right frontal cortex in speech production.

  15. The myelinated fiber loss in the corpus callosum of mouse model of schizophrenia induced by MK-801.

    PubMed

    Xiu, Yun; Kong, Xiang-ru; Zhang, Lei; Qiu, Xuan; Gao, Yuan; Huang, Chun-xia; Chao, Feng-lei; Wang, San-rong; Tang, Yong

    2015-04-01

    Previous magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) investigations have shown that the white matter volume and fractional anisotropy (FA) were decreased in schizophrenia (SZ), which indicated impaired white matter integrity in SZ. However, the mechanism underlying these abnormalities has been less studied. The current study was designed to investigate the possible reasons for white matter abnormalities in the mouse model of SZ induced by NMDA receptor antagonist using the unbiased stereological methods and transmission electron microscope technique. We found that the mice treated with MK-801 demonstrated a series of schizophrenia-like behaviors including hyperlocomotor activity and more anxiety. The myelinated fibers in the corpus callosum (CC) of the mice treated with MK-801 were impaired with splitting lamellae of myelin sheaths and segmental demyelination. The CC volume and the total length of the myelinated fibers in the CC of the mice treated with MK-801 were significantly decreased by 9.4% and 16.8% when compared to those of the mice treated with saline. We further found that the loss of the myelinated fibers length was mainly due to the marked loss of the myelinated nerve fibers with the diameter of 0.4-0.5 μm. These results indicated that the splitting myelin sheaths, demyelination and the loss of myelinated fibers with small diameter might provide one of the structural bases for impaired white matter integrity of CC in the mouse model of SZ. These results might also provide a baseline for further studies searching for the treatment of SZ through targeting white matter.

  16. 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

  17. 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

  18. 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

  19. Topographic organization of V1 projections through the corpus callosum in humans.

    PubMed

    Saenz, M; Fine, I

    2010-10-01

    The visual cortex in each hemisphere is linked to the opposite hemisphere by axonal projections that pass through the splenium of the corpus callosum. Visual-callosal connections in humans and macaques are found along the V1/V2 border where the vertical meridian is represented. Here we identify the topography of V1 vertical midline projections through the splenium within six human subjects with normal vision using diffusion-weighted MR imaging and probabilistic diffusion tractography. Tractography seed points within the splenium were classified according to their estimated connectivity profiles to topographic subregions of V1, as defined by functional retinotopic mapping. First, we report a ventral-dorsal mapping within the splenium with fibers from ventral V1 (representing the upper visual field) projecting to the inferior-anterior corner of the splenium and fibers from dorsal V1 (representing the lower visual field) projecting to the superior-posterior end. Second, we also report an eccentricity gradient of projections from foveal-to-peripheral V1 subregions running in the anterior-superior to posterior-inferior direction, orthogonal to the dorsal-ventral mapping. These results confirm and add to a previous diffusion MRI study (Dougherty et al., 2005) which identified a dorsal/ventral mapping of human splenial fibers. These findings yield a more detailed view of the structural organization of the splenium than previously reported and offer new opportunities to study structural plasticity in the visual system.

  20. 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

  1. Progesterone and Nestorone promote myelin regeneration in chronic demyelinating lesions of corpus callosum and cerebral cortex

    PubMed Central

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

    2014-01-01

    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 anti-inflammatory 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

  2. The corpus callosum in primates: processing speed of axons and the evolution of hemispheric asymmetry.

    PubMed

    Phillips, Kimberley A; Stimpson, Cheryl D; Smaers, Jeroen B; Raghanti, Mary Ann; Jacobs, Bob; Popratiloff, Anastas; Hof, Patrick R; Sherwood, Chet C

    2015-11-01

    Interhemispheric communication may be constrained as brain size increases because of transmission delays in action potentials over the length of axons. Although one might expect larger brains to have progressively thicker axons to compensate, spatial packing is a limiting factor. Axon size distributions within the primate corpus callosum (CC) may provide insights into how these demands affect conduction velocity. We used electron microscopy to explore phylogenetic variation in myelinated axon density and diameter of the CC from 14 different anthropoid primate species, including humans. The majority of axons were less than 1 µm in diameter across all species, indicating that conduction velocity for most interhemispheric communication is relatively constant regardless of brain size. The largest axons within the upper 95th percentile scaled with a progressively higher exponent than the median axons towards the posterior region of the CC. While brain mass among the primates in our analysis varied by 97-fold, estimates of the fastest cross-brain conduction times, as conveyed by axons at the 95th percentile, varied within a relatively narrow range between 3 and 9 ms across species, whereas cross-brain conduction times for the median axon diameters differed more substantially between 11 and 38 ms. Nonetheless, for both size classes of axons, an increase in diameter does not entirely compensate for the delay in interhemispheric transmission time that accompanies larger brain size. Such biophysical constraints on the processing speed of axons conveyed by the CC may play an important role in the evolution of hemispheric asymmetry.

  3. Watershed-based segmentation of the corpus callosum in diffusion MRI

    NASA Astrophysics Data System (ADS)

    Freitas, Pedro; Rittner, Leticia; Appenzeller, Simone; Lapa, Aline; Lotufo, Roberto

    2012-02-01

    The corpus callosum (CC) is one of the most important white matter structures of the brain, interconnecting the two cerebral hemispheres, and is related to several neurodegenerative diseases. Since segmentation is usually the first step for studies in this structure, and manual volumetric segmentation is a very time-consuming task, it is important to have a robust automatic method for CC segmentation. We propose here an approach for fully automatic 3D segmentation of the CC in the magnetic resonance diffusion tensor images. The method uses the watershed transform and is performed on the fractional anisotropy (FA) map weighted by the projection of the principal eigenvector in the left-right direction. The section of the CC in the midsagittal slice is used as seed for the volumetric segmentation. Experiments with real diffusion MRI data showed that the proposed method is able to quickly segment the CC without any user intervention, with great results when compared to manual segmentation. Since it is simple, fast and does not require parameter settings, the proposed method is well suited for clinical applications.

  4. The corpus callosum in primates: processing speed of axons and the evolution of hemispheric asymmetry.

    PubMed

    Phillips, Kimberley A; Stimpson, Cheryl D; Smaers, Jeroen B; Raghanti, Mary Ann; Jacobs, Bob; Popratiloff, Anastas; Hof, Patrick R; Sherwood, Chet C

    2015-11-01

    Interhemispheric communication may be constrained as brain size increases because of transmission delays in action potentials over the length of axons. Although one might expect larger brains to have progressively thicker axons to compensate, spatial packing is a limiting factor. Axon size distributions within the primate corpus callosum (CC) may provide insights into how these demands affect conduction velocity. We used electron microscopy to explore phylogenetic variation in myelinated axon density and diameter of the CC from 14 different anthropoid primate species, including humans. The majority of axons were less than 1 µm in diameter across all species, indicating that conduction velocity for most interhemispheric communication is relatively constant regardless of brain size. The largest axons within the upper 95th percentile scaled with a progressively higher exponent than the median axons towards the posterior region of the CC. While brain mass among the primates in our analysis varied by 97-fold, estimates of the fastest cross-brain conduction times, as conveyed by axons at the 95th percentile, varied within a relatively narrow range between 3 and 9 ms across species, whereas cross-brain conduction times for the median axon diameters differed more substantially between 11 and 38 ms. Nonetheless, for both size classes of axons, an increase in diameter does not entirely compensate for the delay in interhemispheric transmission time that accompanies larger brain size. Such biophysical constraints on the processing speed of axons conveyed by the CC may play an important role in the evolution of hemispheric asymmetry. PMID:26511047

  5. Partial agenesis of the corpus callosum in spina bifida meningomyelocele and potential compensatory mechanisms

    PubMed Central

    Hannay, H. Julia; Dennis, Maureen; Kramer, Larry; Blaser, Susan; Fletcher, Jack M.

    2009-01-01

    After a review of Arthur Benton’s conceptual and methodological contributions to the understanding of normal and pathological development, we discuss agenesis of the corpus callosum (CC), criteria for potential neuroanatomical compensatory mechanisms in CC agenesis, and the results of an examination of magnetic resonance imaging (MRI) data of the CC in 193 children with spina bifida meningomyelocele (SBM). There were 26 CC regional patterns. Although complete agenesis did not occur, partial agenesis was observed in 102 children and within 15 CC regional patterns. Only 4.1% had a normal CC. Quantitative assessment of the area of the CC in 26 NC children and 68 children with SBM revealed that all subgroups with CC anomalies had smaller areas than did a subgroup with a normal CC. Areas were especially small in rostral/splenial agenesis and splenial agenesis but larger with rostral agenesis. Subgroups with normal/hypoplastic regions or complete hypoplasia also had CC areas that were smaller than normal but larger than the areas for the splenial agenesis groups. The relative rarity of anterior commissure enlargement (3.1%) and longitudinal bundles of Probst (0.1%) suggest that these particular fiber tract anomalies are unlikely candidates for structural compensatory mechanisms. The hippocampal commissure, enlarged in 13%, may be a more promising candidate. Overall, however, the functionality of anomalous fiber tracts and commissures in SBM is yet to be determined. PMID:19052950

  6. The tumor suppressor Nf2 regulates corpus callosum development by inhibiting the transcriptional coactivator Yap

    PubMed Central

    Lavado, Alfonso; Ware, Michelle; Paré, Joshua; Cao, Xinwei

    2014-01-01

    The corpus callosum connects cerebral hemispheres and is the largest axon tract in the mammalian brain. Callosal malformations are among the most common congenital brain anomalies and are associated with a wide range of neuropsychological deficits. Crossing of the midline by callosal axons relies on a proper midline environment that harbors guidepost cells emitting guidance cues to instruct callosal axon navigation. Little is known about what controls the formation of the midline environment. We find that two components of the Hippo pathway, the tumor suppressor Nf2 (Merlin) and the transcriptional coactivator Yap (Yap1), regulate guidepost development and expression of the guidance cue Slit2 in mouse. During normal brain development, Nf2 suppresses Yap activity in neural progenitor cells to promote guidepost cell differentiation and prevent ectopic Slit2 expression. Loss of Nf2 causes malformation of midline guideposts and Slit2 upregulation, resulting in callosal agenesis. Slit2 heterozygosity and Yap deletion both restore callosal formation in Nf2 mutants. Furthermore, selectively elevating Yap activity in midline neural progenitors is sufficient to disrupt guidepost formation, upregulate Slit2 and prevent midline crossing. The Hippo pathway is known for its role in controlling organ growth and tumorigenesis. Our study identifies a novel role of this pathway in axon guidance. Moreover, by linking axon pathfinding and neural progenitor behaviors, our results provide an example of the intricate coordination between growth and wiring during brain development. PMID:25336744

  7. 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.

  8. The tumor suppressor Nf2 regulates corpus callosum development by inhibiting the transcriptional coactivator Yap.

    PubMed

    Lavado, Alfonso; Ware, Michelle; Paré, Joshua; Cao, Xinwei

    2014-11-01

    The corpus callosum connects cerebral hemispheres and is the largest axon tract in the mammalian brain. Callosal malformations are among the most common congenital brain anomalies and are associated with a wide range of neuropsychological deficits. Crossing of the midline by callosal axons relies on a proper midline environment that harbors guidepost cells emitting guidance cues to instruct callosal axon navigation. Little is known about what controls the formation of the midline environment. We find that two components of the Hippo pathway, the tumor suppressor Nf2 (Merlin) and the transcriptional coactivator Yap (Yap1), regulate guidepost development and expression of the guidance cue Slit2 in mouse. During normal brain development, Nf2 suppresses Yap activity in neural progenitor cells to promote guidepost cell differentiation and prevent ectopic Slit2 expression. Loss of Nf2 causes malformation of midline guideposts and Slit2 upregulation, resulting in callosal agenesis. Slit2 heterozygosity and Yap deletion both restore callosal formation in Nf2 mutants. Furthermore, selectively elevating Yap activity in midline neural progenitors is sufficient to disrupt guidepost formation, upregulate Slit2 and prevent midline crossing. The Hippo pathway is known for its role in controlling organ growth and tumorigenesis. Our study identifies a novel role of this pathway in axon guidance. Moreover, by linking axon pathfinding and neural progenitor behaviors, our results provide an example of the intricate coordination between growth and wiring during brain development.

  9. 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.

  10. Case study: a patient with agenesis of the corpus callosum with minimal associated neuropsychological impairment.

    PubMed

    Brescian, Natalie E; Curiel, Rosie E; Gass, Carlton S

    2014-01-01

    This is a case study of an 88-year-old man who presented with agenesis of the corpus callosum and colpocephaly. Symptomatically, he reported a sudden onset of mild, intermittent left hand apraxia, but denied any previous manifestations consistent with this type of brain malformation. The patient underwent neuroimaging, evaluation by neurology, and comprehensive neuropsychological testing to determine the nature of any other associated impairments. Test results indicated that he was, with a few exceptions, neuropsychologically normal. He performed well on tests that are highly sensitive to acquired brain dysfunction. His most notable deficit was failed performance in the simultaneous and coordinated use of both hands in using tactile and proprioceptive feedback on the Tactual Performance Test. This case is discussed in terms of plasticity of the developing brain, including compensatory mechanisms, highlighting the variability in clinical outcome in the context of congenital brain malformation. This case study illustrates the strong influence of cerebral plasticity as well as a possible circumscribed manifestation of interhemispheric disconnection.

  11. 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

  12. The role of primary cilia in corpus callosum formation is mediated by production of the Gli3 repressor.

    PubMed

    Laclef, Christine; Anselme, Isabelle; Besse, Laurianne; Catala, Martin; Palmyre, Aurélien; Baas, Dominique; Paschaki, Marie; Pedraza, Maria; Métin, Christine; Durand, Bénédicte; Schneider-Maunoury, Sylvie

    2015-09-01

    Agenesis of the corpus callosum (AgCC) is a frequent brain disorder found in over 80 human congenital syndromes including ciliopathies. Here, we report a severe AgCC in Ftm/Rpgrip1l knockout mouse, which provides a valuable model for Meckel-Grüber syndrome. Rpgrip1l encodes a protein of the ciliary transition zone, which is essential for ciliogenesis in several cell types in mouse including neuroepithelial cells in the developing forebrain. We show that AgCC in Rpgrip1l(-/-) mouse is associated with a disturbed location of guidepost cells in the dorsomedial telencephalon. This mislocalization results from early patterning defects and abnormal cortico-septal boundary (CSB) formation in the medial telencephalon. We demonstrate that all these defects primarily result from altered GLI3 processing. Indeed, AgCC, together with patterning defects and mispositioning of guidepost cells, is rescued by overexpressing in Rpgrip1l(-/-) embryos, the short repressor form of the GLI3 transcription factor (GLI3R), provided by the Gli3(Δ699) allele. Furthermore, Gli3(Δ699) also rescues AgCC in Rfx3(-/-) embryos deficient for the ciliogenic RFX3 transcription factor that regulates the expression of several ciliary genes. These data demonstrate that GLI3 processing is a major outcome of primary cilia function in dorsal telencephalon morphogenesis. Rescuing CC formation in two independent ciliary mutants by GLI3(Δ699) highlights the crucial role of primary cilia in maintaining the proper level of GLI3R required for morphogenesis of the CC.

  13. A Preliminary Investigation of Corpus Callosum and Anterior Commissure Aberrations in Aggressive Youth with Bipolar Disorders

    PubMed Central

    Tamm, Leanne; Walley, Annie; Simmons, Alex; Rollins, Nancy; Chia, Jonathan; Soares, Jair C.; Emslie, Graham J.; Fan, Xin; Huang, Hao

    2012-01-01

    Abstract Objective Although behavioral deficits in bipolar disorder (BPD) are well described, the specific brain white matter (WM) disruptions have not been completely characterized, and neural mechanisms underlying dysfunction in BPD are not well established, particularly for youth with BPD and aggression. This preliminary study utilized diffusion tensor imaging (DTI) to investigate commissural tracts (corpus callosum [CC] and anterior commissure [AC]) in youth with BPD, because disruption of interhemispheric communication may contribute to the emotional deficits that are characteristic of the illness. Method DTI was used to investigate WM in 10 youth (7–17 years of age) with BPD and 10 typically developing age-matched controls. Tract-based spatial statistics voxel-wise analysis was used to compare fractional anisotropy (FA) of the two groups. We specifically focused on five subdivisions of the midsagittal CC as well as on the decussation of AC, which connects the temporal lobes. Exploratory correlations between FA values and life history of aggression scores were calculated for the BPD group. Results Youth with BPD had significantly lower FA values in the callosal genu and AC. FA values in the AC were negatively correlated with a life history of aggression in the BPD group. Conclusions These results contribute to a growing literature implicating a role for the genu of the CC in BPD and are the first to report WM variations in the AC of children with BPD. Taken together with the correlational data for aggression and the role of the AC in emotional processing, our data provide preliminary evidence for a possible association between the structural integrity of the WM of the AC and aggression in pediatric BPD. PMID:22375854

  14. 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.

  15. 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

  16. Corticosteroids impair remyelination in the corpus callosum of cuprizone-treated mice.

    PubMed

    Clarner, T; Parabucki, A; Beyer, C; Kipp, M

    2011-07-01

    Corticosteroids (CS) are effective in the treatment of many brain disorders, such as multiple sclerosis (MS) or traumatic brain injury. This has been scrutinised in different experimental animal models. However, neither the mechanisms, nor the site of CS action are fully understood. Short-term high-dose CS treatment improves MS symptoms and severity of clinical disability during an acute inflammatory exacerbation of disease. In the present study, we analysed the influence of CS on the expression of cellular and molecular markers of spontaneous endogenous remyelination in the toxic non-immune cuprizone animal model at early (9 days) and intermediate (21 days) remyelination, as well as steroidal effects in primary astrocytes and oligodendrocyte progenitor cultures. Dexamethasone (Dex) and methylprednisolone (MP) induced a higher expression of the differentiation markers myelin basic protein and proteolipid protein (PLP) in cultured oligodendrocyte progenitor cells (OPC). CS exposure of primary cultured astrocytes resulted in a greater expression of those genes involved in OPC proliferation [fibroblast growth factor 2 (FGF2) and platelet-derived growth factor (PDGF)-αα] and a reduced expression of the pro-maturation factor insulin-like growth factor 1. Pro-maturating effects of CS were completely blocked by FGF2 and PDGF-αα co-application in OPC cultures. MP treatment in vivo resulted in a reduced recovery of PLP-staining intensity, whereas the re-population of the demyelinated corpus callosum with adenomatous polyposis coli-expressing oligodendrocytes was not affected. The numbers of brain intrinsic inflammatory cells, microglia and astrocytes during remyelination were similar in placebo and MP-treated animals. Our findings suggest that treatment with CS might have, in addition to the well-known benefical effects on inflammatory processes, a negative influence on remyelination.

  17. 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

  18. A case of ring chromosome 22 with deletion of the 22q13.3 region associated with agenesis of the corpus callosum, fornix and septum pellucidum.

    PubMed

    Delcán, José; Orera, María; Linares, Rafael; Saavedra, Dolores; Palomar, Angustias

    2004-08-01

    We report a 16-week-gestation foetus obtained by voluntary abortion after prenatal diagnosis, in which a ring chromosome 22 was observed with deletion of the 22q13.3 region. A prenatal study of the amniotic fluid by standard chromosome technique with G bands and FISH (fluorescence in situ hybridisation) was performed. After the abortion, the anatomopathological study of the obtained foetus was carried out. Morphological and histological analysis of the foetus did not reveal severe physical abnormalities, although alterations of the nervous system were observed consisting of corpus callosum, fornix and septum pellucidum agenesia. It could be that the genes in this region that were involved in the development of the central nervous system were responsible for the alterations found in the morphological study. The wide range of manifestations observed in patients with this cytogenetic alteration is probably due to size differences in the deleted region.

  19. Anatomical variants of brain structure: confused spatial relationship of the fornix to the corpus callosum and anterior commissure.

    PubMed

    Hori, A

    1997-12-01

    How the developing nerve fibers are guided to and able to find their target is currently a matter of research. As examples of the false guidance of axons, anatomical variants of the spatial relationship of the columna fornicis to the corpus callosum and the anterior commissure are demonstrated. In a 60 year-old female patient, some of the fibers of the genu corporis callosi were found to be entrapped by a fornix fiber bundle. The brain of a 20 year-old man showed that the unilateral anterior commissure ran posterior to the columna fornicis. These changes were clinically insignificant.

  20. Diabetes insipidus with impaired osmotic regulation in septo-optic dysplasia and agenesis of the corpus callosum.

    PubMed Central

    Masera, N; Grant, D B; Stanhope, R; Preece, M A

    1994-01-01

    The clinical and endocrinological findings in 24 children with septo-optic dysplasia and/or agenesis of the corpus callosum are described with particular reference to posterior pituitary function. Nine had diabetes insipidus. The prevalence of diabetes insipidus was similar in children with complete and incomplete forms of septo-optic dysplasia. Maintenance of normal osmotic balance was very difficult in six of these children, even after the introduction of treatment with vasopressin, either as desmopressin, or lysine vasopressin spray in one of the early cases. PMID:8110009

  1. 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.

  2. Mild Encephalopathy with Reversible Lesions in the Splenium of Corpus Callosum and Bilateral Cerebral Deep White Matter in Identical Twins

    PubMed Central

    Tahara, Junko; Shinozuka, Jun; Awaguni, Hitoshi; Tanaka, Shin-ichiro; Makino, Shigeru; Maruyama, Rikken; Imashuku, Shinsaku

    2016-01-01

    Identical twin brothers developed mild encephalopathy at the age of 7.0 and 9.7 years (Patient 1) and 10.7 years (Patient 2). Patient 1 had influenza A at the time of his second episode, but triggering agents were not evident at the first episode. The triggering agents in Patient 2 were unclear. The neurological features of both patients included transient facial numbness, left arm paresis, dysarthria, and gait disturbance. Diffusion-weighted images from magnetic resonance imaging showed high signal levels at the splenium of corpus callosum and in the bilateral cerebral deep white matter. These results are characteristic of mild encephalitis/encephalopathy with a reversible isolated splenium of corpus callosum lesion. All three episodes were treated with a methylprednisolone pulse. Acyclovir was also administered to Patient 2 and to Patient 1 during his first episode. Patient 1 received an anti-influenza agent and intravenous immunoglobulin during his second episode. Both patients recovered completely without sequelae. Genetic factors, which may predispose identical twins to develop encephalopathy, are discussed. PMID:27777703

  3. Traumatic axonal injury: the prognostic value of lesion load in corpus callosum, brain stem, and thalamus in different magnetic resonance imaging sequences.

    PubMed

    Moen, Kent G; Brezova, Veronika; Skandsen, Toril; Håberg, Asta K; Folvik, Mari; Vik, Anne

    2014-09-01

    The aim of this study was to explore the prognostic value of visible traumatic axonal injury (TAI) loads in different MRI sequences from the early phase after adjusting for established prognostic factors. Likewise, we sought to explore the prognostic role of early apparent diffusion coefficient (ADC) values in normal-appearing corpus callosum. In this prospective study, 128 patients (mean age, 33.9 years; range, 11-69) with moderate (n = 64) and severe traumatic brain injury (TBI) were examined with MRI at a median of 8 days (range, 0-28) postinjury. TAI lesions in fluid-attenuated inversion recovery (FLAIR), diffusion-weighted imaging (DWI), and T2*-weighted gradient echo (T2*GRE) sequences were counted and FLAIR lesion volumes estimated. In patients and 47 healthy controls, mean ADC values were computed in 10 regions of interests in the normal-appearing corpus callosum. Outcome measure was the Glasgow Outcome Scale-Extended (GOS-E) at 12 months. In patients with severe TBI, number of DWI lesions and volume of FLAIR lesions in the corpus callosum, brain stem, and thalamus predicted outcome in analyses with adjustment for age, Glasgow Coma Scale score, and pupillary dilation (odds ratio, 1.3-6.9; p = <0.001-0.017). The addition of Rotterdam CT score and DWI lesions in the corpus callosum yielded the highest R2 (0.24), compared to all other MRI variables, including brain stem lesions. For patients with moderate TBI only the number of cortical contusions (p = 0.089) and Rotterdam CT score (p = 0.065) tended to predict outcome. Numbers of T2*GRE lesions did not affect outcome. Mean ADC values in the normal-appearing corpus callosum did not differ from controls. In conclusion, the loads of visible TAI lesions in the corpus callosum, brain stem, and thalamus in DWI and FLAIR were independent prognostic factors in patients with severe TBI. DWI lesions in the corpus callosum were the most important predictive MRI variable. Interestingly, number of cortical

  4. 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

  5. Expanding the Clinical Spectrum of SPG11 Gene Mutations in Recessive Hereditary Spastic Paraplegia with Thin Corpus Callosum

    PubMed Central

    Aleem, Alice Abdel; Abu-Shahba, Nourhan; Swistun, Dominika; Silhavy, Jennifer; Bielas, Stephanie L.; Sattar, Shifteh; Gleeson, Joseph G.; Zaki, Maha

    2011-01-01

    Hereditary spastic paraplegia (HSP) represents a large group of neurological disorders characterized by progressive spasticity of the lower limbs. One subtype of HSP shows an autosomal recessive form of inheritance with this corpus callosum (ARHSP-TCC), and displays genetic heterogeneity with four known loci. We identified a consanguineous Egyptian family with five affected individuals with ARHSP-TCC. We found linkage to the SPG11 locus and identified a novel homozygous p.Q498X stop codon mutation in exon 7 in the SPG11 gene encoding Spatacsin. Cognitive impairment and polyneuropathy, reported as frequent in SPG11, were not evident. This family supports the importance of SPG11 as a frequent cause for ARHSP-TCC, and expands the clinic SPG11 spectrum. PMID:20971220

  6. Auditory interhemispheric transfer in relation to patterns of partial agenesis and hypoplasia of the corpus callosum in spina bifida meningomyelocele

    PubMed Central

    Hannay, H. Julia; Walker, Amy; Dennis, Maureen; Kramer, Larry; Blaser, Susan; Fletcher, Jack M.

    2009-01-01

    Spina bifida meningomyelocele with hydrocephalus (SBM) is commonly associated with anomalies of the corpus callosum (CC). We describe MRI patterns of regional CC agenesis and relate CC anomalies to functional laterality based on a dichotic listening test in 90 children with SBM and 27 typically developing controls. Many children with SBM (n = 40) showed regional CC anomalies in the form of agenesis of the rostrum and0or splenium, and a smaller number (n = 20) showed hypoplasia (thinning) of all CC regions (rostrum, genu, body, and splenium). The expected right ear advantage (REA) was exhibited by normal controls and children with SBM having a normal or hypoplastic splenium. It was not shown by children with SBM who were left handed, missing a splenium, or had a higher level spinal cord lesion. Perhaps the right hemisphere of these children is more involved in processing some aspects of linguistic stimuli. PMID:18764972

  7. Taurine attenuates hippocampal and corpus callosum damage, and enhances neurological recovery after closed head injury in rats.

    PubMed

    Gu, Y; Zhao, Y; Qian, K; Sun, M

    2015-04-16

    The protective effects of taurine against closed head injury (CHI) have been reported. This study was designed to investigate whether taurine reduced white matter damage and hippocampal neuronal death through suppressing calpain activation after CHI in rats. Taurine (50 mg/kg) was administered intravenously 30 min and 4 h again after CHI. It was found that taurine lessened the corpus callosum damage, attenuated the neuronal cell death in hippocampal CA1 and CA3 subfields and improved the neurological functions 7 days after CHI. Moreover, it suppressed the over-activation of calpain, enhanced the levels of calpastatin, and reduced the degradation of neurofilament heavy protein, myelin basic protein and αII-spectrin in traumatic tissue 24 h after CHI. These data confirm the protective effects of taurine against gray and white matter damage due to CHI, and suggest that down-regulating calpain activation could be one of the protective mechanisms of taurine against CHI.

  8. 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

  9. Individuals with agenesis of the corpus callosum show sensory processing differences as measured by the Sensory Profile

    PubMed Central

    Dunn, Winnie; Strominger, Zoe; Sherr, Elliott H.; Marco, Elysa

    2015-01-01

    Objective Given reports of high pain thresholds and reduced auditory response in individuals with Agenesis of the Corpus Callosum (AgCC), this study investigated whether affected participants report atypical experiences and behaviors on a well-established sensory processing measure. Methods Fourteen participants with AgCC (ages 11-59) completed the Adolescent/Adult Sensory Profile (Brown & Dunn, 2001). Sensory profile scales were classified as “Atypical” if they were more than one standard deviation from the mean. Results Fifty-seven percent of participants with AgCC reported reduced sensory registration as compared to an expected 16% of the normative sample. Similarly, 50% of the AgCC participants reported atypically increased auditory processing difficulties. Conclusions Using a well-established sensory processing questionnaire, participants with AgCC reported measurable differences in multiple aspects of sensory processing. The most notable difference was in the quadrant of low sensory registration, suggesting that individuals with AgCC may require sensory information to be presented more slowly or at a higher intensity for adequate processing. The sensory modality that was most affected was the auditory system, which is consistent with increased rates of language disorders and Autism Spectrum Disorders in this population. Understanding sensory processing in individuals with AgCC can both elucidate the role of inter-hemispheric transfer in the development of intact sensory processing as well as contribute to our knowledge of the role of the corpus callosum in a range of disorders in which sensory processes are impacted. PMID:25528608

  10. Sgk1 regulates desmoglein 1 expression levels in oligodendrocytes in the mouse corpus callosum after chronic stress exposure.

    PubMed

    Miyata, Shingo; Yoshikawa, Keiko; Taniguchi, Manabu; Ishikawa, Toshiko; Tanaka, Takashi; Shimizu, Shoko; Tohyama, Masaya

    2015-08-14

    Major depression, one of the most prevalent mental illnesses, is thought to be a multifactorial disease related to both genetic and environmental factors. However, the genes responsible for and the pathogenesis of major depression at the molecular level remain unclear. Recently, we reported that stressed mice with elevated plasma corticosterone levels show upregulation and activation of serum glucocorticoid-regulated kinase (Sgk1) in oligodendrocytes. Active Sgk1 causes phosphorylation of N-myc downstream-regulated gene 1 (Ndrg1), and phospho-Ndrg1 increases the expression of N-cadherin, α-catenin, and β-catenin in oligodendrocytes. This activation of the Sgk1 cascade results in morphological changes in the oligodendrocytes of nerve fiber bundles, such as those present in the corpus callosum. However, little is known about the molecular functions of the traditional and/or desmosomal cadherin superfamily in oligodendrocytes. Therefore, in this study, we aimed to elucidate the functions of the desmosomal cadherin superfamily in oligodendrocytes. Desmoglein (Dsg) 1, Dsg2, and desmocollin 1 (Dsc1) were found to be expressed in the corpus callosum of mouse brain, and the expression of a subtype of Dsg1, Dsg1c, was upregulated in oligodendrocytes after chronic stress exposure. Furthermore, Dsg1 proteins were localized around the plasma membrane regions of oligodendrocytes. A study in primary oligodendrocyte cultures also revealed that chronic upregulation of Sgk1 by dexamethasone administration is involved in upregulation of Dsg1c mRNA. These results may indicate that chronic stress induced Sgk1 activation in oligodendrocytes, which increases Dsg1 expression near the plasma membrane. Thus, Dsg1 upregulation may be implicated in the molecular mechanisms underlying the morphological changes in oligodendrocytes in response to chronic stress exposure. PMID:26043694

  11. 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.

  12. EphB1 and EphB2 intracellular domains regulate the formation of the corpus callosum and anterior commissure.

    PubMed

    Robichaux, Michael A; Chenaux, George; Ho, Hsin-Yi Henry; Soskis, Michael J; Greenberg, Michael E; Henkemeyer, Mark; Cowan, Christopher W

    2016-04-01

    The two cortical hemispheres of the mammalian forebrain are interconnected by major white matter tracts, including the corpus callosum (CC) and the posterior branch of the anterior commissure (ACp), that bridge the telencephalic midline. We show here that the intracellular signaling domains of the EphB1 and EphB2 receptors are critical for formation of both the ACp and CC. We observe partial and complete agenesis of the corpus callosum, as well as highly penetrant ACp misprojection phenotypes in truncated EphB1/2 mice that lack intracellular signaling domains. Consistent with the roles for these receptors in formation of the CC and ACp, we detect expression of these receptors in multiple brain regions associated with the formation of these forebrain structures. Taken together, our findings suggest that a combination of forward and reverse EphB1/2 receptor-mediated signaling contribute to ACp and CC axon guidance.

  13. Fetal development of the corpus callosum: Insights from a 3T DTI and tractography study in a patient with segmental callosal agenesis.

    PubMed

    Scola, Elisa; Sirgiovanni, Ida; Avignone, Sabrina; Cinnante, Claudia Maria; Biffi, Riccardo; Fumagalli, Monica; Triulzi, Fabio

    2016-10-01

    Commissural embryology mechanisms are not yet completely understood. The study and comprehension of callosal dysgenesis can provide remarkable insights into embryonic or fetal commissural development. The diffusion tensor imaging (DTI) technique allows the in vivo analyses of the white-matter microstructure and is a valid tool to clarify the disturbances of brain connections in patients with dysgenesis of the corpus callosum (CC). The segmental callosal agenesis (SCAG) is a rare partial agenesis of the corpus callosum (ACC). In a newborn with SCAG the DTI and tractography analyses proved that the CC was made of two separate segments consisting respectively of the ventral part in the genu and body of the CC, connecting the frontal lobes, and the dorsal part in the CC splenium and the attached hippocampal commissure (HC), connecting the parietal lobes and the fornix. These findings support the embryological thesis of a separated origin of the ventral and the dorsal parts of the CC.

  14. Fetal development of the corpus callosum: Insights from a 3T DTI and tractography study in a patient with segmental callosal agenesis.

    PubMed

    Scola, Elisa; Sirgiovanni, Ida; Avignone, Sabrina; Cinnante, Claudia Maria; Biffi, Riccardo; Fumagalli, Monica; Triulzi, Fabio

    2016-10-01

    Commissural embryology mechanisms are not yet completely understood. The study and comprehension of callosal dysgenesis can provide remarkable insights into embryonic or fetal commissural development. The diffusion tensor imaging (DTI) technique allows the in vivo analyses of the white-matter microstructure and is a valid tool to clarify the disturbances of brain connections in patients with dysgenesis of the corpus callosum (CC). The segmental callosal agenesis (SCAG) is a rare partial agenesis of the corpus callosum (ACC). In a newborn with SCAG the DTI and tractography analyses proved that the CC was made of two separate segments consisting respectively of the ventral part in the genu and body of the CC, connecting the frontal lobes, and the dorsal part in the CC splenium and the attached hippocampal commissure (HC), connecting the parietal lobes and the fornix. These findings support the embryological thesis of a separated origin of the ventral and the dorsal parts of the CC. PMID:27549148

  15. 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

  16. Morphometric analysis of brain images with reduced number of statistical tests: a study on the gender-related differentiation of the corpus callosum

    PubMed Central

    Kontos, Despina; Megalooikonomou, Vasileios; Gee, James C.

    2009-01-01

    Summary Objective We evaluate the feasibility of applying dynamic recursive partitioning (DRP), an image analysis technique, to perform morphometric analysis. We apply DRP to detect and characterize discriminative morphometric characteristics between anatomical brain structures from different groups of subjects. Our method reduces the number of statistical tests, commonly required by pixel-wise statistics, alleviating the effect of the multiple comparison problem. Methods and Materials The main idea of DRP is to partition the two-dimensional (2D) image adaptively into progressively smaller sub-regions until statistically significant discriminative regions are detected. The partitioning process is guided by statistical tests applied on groups of pixels. By performing statistical tests on groups of pixels rather than on individual pixels, the number of statistical tests is effectively reduced. This reduction of statistical tests restricts the effect of the multiple comparison problem (i.e. type-I error). We demonstrate an application of DRP for detecting gender-related morphometric differentiation of the corpus callosum. DRP was applied to template deformation fields computed from registered magnetic resonance images of the corpus callosum in order to detect regions of significant expansion or contraction between female and male subjects. Results DRP was able to detect regions comparable to those of pixel-wise analysis, while reducing the number of required statistical tests up to almost 50%. The detected regions were in agreement with findings previously reported in the literature. Statistically significant discriminative morphological variability was detected in the posterior corpus callosum region, the isthmus and the anterior corpus callosum. In addition, by operating on groups of pixels, DRP appears to be less prone to detecting spatially diffused and isolated outlier pixels as significant. Conclusion DRP can be a viable approach for detecting discriminative

  17. "Multicystic dysplastic kidney (Potter type II syndrome) and agenesis of corpus callosum (ACC) in two consecutive pregnancies: a possible teratogenic effect of electromagnetic exposure in utero".

    PubMed

    Tonni, Gabriele; Azzoni, Daniela; Ventura, Alessandro; Ambrosetti, Fabrizio; De Felice, Claudio

    2008-01-01

    Agenesis of the corpus callosum is found in about 5 per 1,000 births and it is due to maldevelopment or, secondary, to destructive lesions. Multicystic dysplastic kidneys is a consequence of either developmental failure of the mesonephric blastema to form nephrons or to early urinary obstruction due to urethral or ureteric atresia and can be found in about 1 per 1,000 live births. A case of fetal multicystic dysplastic kidney disease (Potter type II syndrome) and complete agenesis of the corpus callosum demonstrated by the presence of Probst bundles associated with colpocephaly occurring in the same mother in her two consecutive pregnancies is reported. Data regarding possible teratogenetic effect due to electromagnetic exposure in utero have also been investigated and raised suspicionus as a potential risk factor. In cases of suspected second trimester ultrasound diagnosis of agenesis of corpus callosum (ACC), the following clinical management should be recommended: fetal karyotype; a second level scan with differentiation between underlying conditions such as hydrocephalus and holoprosencephaly; antenatal MRI to enhance the diagnostic accuracy of possible associated neuronal migration (when possible); and direct demonstration of the presence of the Probst bundles to neurohistology.

  18. [Nevoid basal cell carcinoma syndrome with corpus callosum agenesis, PTCH1 mutation and absence of basal cell carcinoma].

    PubMed

    Mazzuoccolo, Luis D; Martínez, María Florencia; Muchnik, Carolina; Azurmendi, Pablo J; Stengel, Fernando

    2014-01-01

    Nevoid Basal Cell Carcinoma Syndrome (NBCCS) or Gorlin-Goltz syndrome is a rare autosomal dominant disorder, mainly due to PTCH1 gene mutations, that comprises a broad spectrum of clinical manifestations. The presence of multiple basal cell carcinomas (BCCs) is a cardinal sign in NBCCS, therefore cases in which BCCs are absent entails a delay in the diagnosis.We present a 14 years old boy with a clinical diagnosis of NBCCS by the presence of odontogenic cysts, hypertelorism, macrocephaly, and corpus callosum agenesia, but with absence of skin lesions. His 43 years old mother has NBCCS diagnosis and no history of BCCs. For a deeper study, PTCH1 mutation screening from peripheral blood samples were performed by both bidirectional sequencing and multiplex ligation dependent probe amplification (MLPA) techniques. The proband and his mother carry 25 pb duplication in exon 10 (c.1375dupl25bp) that causes a reading frameshift with a premature stop codon. Bioinformatics analysis predicted that this mutation results in a truncated protein shorter than normal. Our results suggest that complete clinical and genealogical studies accompanied by genetic analysis are essential in the early detection of the NBCCS cases such the one presented here. PMID:25188659

  19. 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

  20. Single-shot T1 mapping of the corpus callosum: a rapid characterization of fiber bundle anatomy.

    PubMed

    Hofer, Sabine; Wang, Xiaoqing; Roeloffs, Volkert; Frahm, Jens

    2015-01-01

    Using diffusion-tensor magnetic resonance imaging and fiber tractography the topographic organization of the human corpus callosum (CC) has been described to comprise five segments with fibers projecting into prefrontal (I), premotor and supplementary motor (II), primary motor (III), and primary sensory areas (IV), as well as into parietal, temporal, and occipital cortical areas (V). In order to more rapidly characterize the underlying anatomy of these segments, this study used a novel single-shot T1 mapping method to quantitatively determine T1 relaxation times in the human CC. A region-of-interest analysis revealed a tendency for the lowest T1 relaxation times in the genu and the highest T1 relaxation times in the somatomotor region of the CC. This observation separates regions dominated by myelinated fibers with large diameters (somatomotor area) from densely packed smaller axonal bundles (genu) with less myelin. The results indicate that characteristic T1 relaxation times in callosal profiles provide an additional means to monitor differences in fiber anatomy, fiber density, and gray matter in respective neocortical areas. In conclusion, rapid T1 mapping allows for a characterization of the axonal architecture in an individual CC in less than 10 s. The approach emerges as a valuable means for studying neocortical brain anatomy with possible implications for the diagnosis of neurodegenerative processes.

  1. 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

  2. SLC1A4 mutations cause a novel disorder of intellectual disability, progressive microcephaly, spasticity and thin corpus callosum.

    PubMed

    Heimer, G; Marek-Yagel, D; Eyal, E; Barel, O; Oz Levi, D; Hoffmann, C; Ruzzo, E K; Ganelin-Cohen, E; Lancet, D; Pras, E; Rechavi, G; Nissenkorn, A; Anikster, Y; Goldstein, D B; Ben Zeev, B

    2015-10-01

    Two unrelated patients, presenting with significant global developmental delay, severe progressive microcephaly, seizures, spasticity and thin corpus callosum (CC) underwent trio whole-exome sequencing. No candidate variant was found in any known genes related to the phenotype. However, crossing the data of the patients illustrated that they both manifested pathogenic variants in the SLC1A4 gene which codes the ASCT1 transporter of serine and other neutral amino acids. The Ashkenazi patient is homozygous for a deleterious missense c.766G>A, p.(E256K) mutation whereas the Ashkenazi-Iraqi patient is compound heterozygous for this mutation and a nonsense c.945delTT, p.(Leu315Hisfs*42) mutation. Structural prediction demonstrates truncation of significant portion of the protein by the nonsense mutation and speculates functional disruption by the missense mutation. Both mutations are extremely rare in general population databases, however, the missense mutation was found in heterozygous mode in 1:100 Jewish Ashkenazi controls suggesting a higher carrier rate among Ashkenazi Jews. We conclude that SLC1A4 is the disease causing gene of a novel neurologic disorder manifesting with significant intellectual disability, severe postnatal microcephaly, spasticity and thin CC. The role of SLC1A4 in the serine transport from astrocytes to neurons suggests a possible pathomechanism for this disease and implies a potential therapeutic approach.

  3. 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

  4. 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

  5. The integrity of corpus callosum and cluster B personality disorders: a quantitative MRI study in juvenile myoclonic epilepsy.

    PubMed

    Filho, Gerardo Maria de Araújo; Jackowski, Andrea Parolin; Lin, Katia; Silva, Ivaldo; S B Guaranha, Mirian; Guilhoto, Laura M F F; Júnior, Henrique Carrete; Yacubian, Elza Márcia T; Bressan, Rodrigo Affonseca

    2010-04-16

    Evidence suggests increased prevalence of cluster B personality disorders (PD) among patients with juvenile myoclonic epilepsy (JME), which has been associated with worse seizure control and more psychosocial dysfunctions. A preliminary voxel-based morphometry study demonstrated corpus callosum (CC) volume reduction in patients with JME and cluster B PD, particularly in the posterior midbody and isthmus. In this study we aimed to follow up these results with region of interest analysis. Sixteen JME patients with cluster B PD, 38 JME patients without any psychiatric disorder, and 30 demographically matched healthy controls submitted to a psychiatric evaluation and a magnetic resonance imaging scan. The total and regional callosal areas were obtained from the midsagittal slice using a semi-automated program. Psychiatric evaluation was performed through SCID-I and -II. Significant reductions in the posterior region of the CC were observed in the JME with PD group relative to the other groups. These data support previous findings of callosal reductions in cluster B PD, as well as a possible involvement of CC in patients with JME and such personality characteristics.

  6. Corpus Callosum Segment Circumference Is Associated With Response Control in Children With Attention-Deficit Hyperactivity Disorder (ADHD)

    PubMed Central

    McNally, Melanie A.; Crocetti, Deana; Mahone, E. Mark; Denckla, Martha B.; Suskauer, Stacy J.; Mostofsky, Stewart H.

    2010-01-01

    Response control is impaired in attention-deficit hyperactivity disorder (ADHD). Given the corpus callosum's role in response control, we compared callosal morphology in 64 children with ADHD and 64 typically developing children, aged 7 to 13 years, and investigated the relationships between callosal morphology and response control. Area and circumference of 5 callosal segments (genu, rostral body, midbody, isthmus, and splenium) were normalized for cerebral volume and examined for correlation with mean reaction time, intrasubject variability, and/or commission error rate from a go/no-go task. There were no between-group differences in segment areas or circumferences. Reaction time correlated with midbody circumference for boys with ADHD and isthmus circumference for girls with ADHD. For the entire cohort, rostral body circumference correlated with intra-subject variability. Impaired response control in ADHD is associated with anomalies in frontal interhemispheric connections. Future studies examining callosal shape will illuminate the anatomic basis of correlations between callosal segment circumference and response control. PMID:20139403

  7. 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.

  8. Acute effects of neonatal dexamethasone treatment on proliferation and astrocyte immunoreactivity in hippocampus and corpus callosum: towards a rescue strategy.

    PubMed

    Claessens, Sanne E F; Belanoff, Joseph K; Kanatsou, Sofia; Lucassen, Paul J; Champagne, Danielle L; de Kloet, E Ronald

    2012-10-30

    Dexamethasone (DEX), a synthetic glucocorticoid, has been used to treat respiratory distress syndrome in prematurely born infants. Despite the important short-term benefit on lung function, there is growing concern about the long-term outcome of this treatment, since follow-up studies of prematurely born infants have shown lasting adverse neurodevelopmental effects. Since the mechanism underlying these neurodevelopmental impairments is largely unknown, the aim of the present study was (i) to investigate the acute effects of neonatal DEX treatment on the developing brain; and (ii) to block specifically the effects of DEX on the brain by central administration of the glucocorticoid receptor (GR) antagonist mifepristone. Long Evans rat pups were injected subcutaneously with tapering doses of DEX or saline (SAL) on postnatal days (pnd) 1, 2 and 3. Separate groups received intracerebroventricular injections with mifepristone prior to DEX treatment. On pnd 4 and 10, pups were sacrificed and brains collected for analysis of cell proliferation (Ki-67) and astrogliosis (GFAP). We report that neonatal DEX treatment reduced hippocampal cell proliferation on pnd 4, an effect that was normalized by pnd 10. Although on pnd 4, GFAP expression was not affected, DEX treatment caused a significant reduction in the number and density of astrocytes in hippocampus and corpus callosum on pnd 10, which was normalized by mifepristone pre-treatment. These acute alterations in the neonate brain might underlie later functional impairments reported in DEX-treated animals and humans and further illustrate the impact of early GR activation on brain development.

  9. 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

  10. Heparan Sulfotransferases Hs6st1 and Hs2st Keep Erk in Check for Mouse Corpus Callosum Development

    PubMed Central

    Clegg, James M.; Conway, Christopher D.; Howe, Kathy M.; Price, David J.; Mason, John O.; Turnbull, Jeremy E.; Basson, M. Albert

    2014-01-01

    The corpus callosum (CC) connects the left and right cerebral hemispheres in mammals and its development requires intercellular communication at the telencephalic midline mediated by signaling proteins. Heparan sulfate (HS) is a sulfated polysaccharide that decorates cell surface and extracellular matrix proteins and regulates the biological activity of numerous signaling proteins via sugar–protein interactions. HS is subject to regulated enzymatic sulfation and desulfation and an attractive, although not proven, hypothesis is that the biological activity of HS is regulated by a sugar sulfate code. Mutant mouse embryos lacking the heparan sulfotransferases Hs2st or Hs6st1 have severe CC phenotypes and form Probst bundles of noncrossing axons flanking large tangles of midline glial processes. Here, we identify a precocious accumulation of Sox9-expressing glial cells in the indusium griseum region and a corresponding depletion at the glial wedge associated with the formation of Probst bundles along the rostrocaudal axis in both mutants. Molecularly, we found a surprising hyperactivation of Erk signaling in Hs2st−/− (2-fold) and Hs6st1−/− (6-fold) embryonic telencephalon that was most striking at the midline, where Erk signaling is lowest in wild-types, and a 2-fold increase in Fgf8 protein levels in Hs6st1−/− embryos that could underpin Erk hyperactivation and excessive glial movement to the indusium griseum. The tightly linked Hs6st1−/− CC glial and axonal phenotypes can be rescued by genetic or pharmacological suppression of Fgf8/Erk axis components. Overall, our data fit a model in which Hs2st and Hs6st1 normally generate conditions conducive to CC development by generating an HS-containing environment that keeps Erk signaling in check. PMID:24501377

  11. SPG11 mutations cause Kjellin syndrome, a hereditary spastic paraplegia with thin corpus callosum and central retinal degeneration.

    PubMed

    Orlén, Hanna; Melberg, Atle; Raininko, Raili; Kumlien, Eva; Entesarian, Miriam; Söderberg, Per; Påhlman, Magnus; Darin, Niklas; Kyllerman, Mårten; Holmberg, Eva; Engler, Henry; Eriksson, Urban; Dahl, Niklas

    2009-10-01

    Autosomal recessive hereditary spastic paraplegia (ARHSP) with thin corpus callosum (TCC) is genetically heterogenous and approximately 35% of patients carry mutations in either of the SPG11 or SPG15 genes. Disease onset is during the first three decades of life with spastic paraplegia and mental impairment. Peripheral neuropathy and amyotrophy may occur. Kjellin syndrome is characterized by central retinal degeneration in addition to ARHSP-TCC and the disease is associated with mutations in the SPG15 gene. We identified five patients in four unrelated kindreds with spastic paraplegia and mental impairment. Magnetic resonance imaging revealed TCC, atrophy elsewhere in the brain and increased T2 signal intensity in the periventricular white matter. Probands from the four kindreds were screened for mutations in the SPG11 gene. All patients were found homozygous or compound heterozygous for truncating SPG11 mutations of which four are reported for the first time. Ophthalmological investigations revealed that the four index cases have central retinal degeneration consistent with Kjellin syndrome. PET examinations with N-[11C-methyl]-L-deuterodeprenyl (DED) and fluor-18 2-fluorodeoxyglucose (FDG) were performed in two patients with Kjellin syndrome. We observed a reduced glucose uptake in the thalami, anterior cingulum, and sensorimotor cortex indicating neuronal loss, and an increased DED binding in the thalami and pons which suggests astrogliosis. From our results we extend the SPG11 associated phenotype to comprise also Kjellin syndrome, previously found to be associated with mutations in the SPG15 gene. We anticipate that degeneration of the central retina is a common and previously unrecognized feature in SPG11 related disease.

  12. Proteomics of the corpus callosum unravel pivotal players in the dysfunction of cell signaling, structure, and myelination in schizophrenia brains.

    PubMed

    Saia-Cereda, Verônica M; Cassoli, Juliana S; Schmitt, Andrea; Falkai, Peter; Nascimento, Juliana M; Martins-de-Souza, Daniel

    2015-10-01

    Schizophrenia is an incurable and debilitating mental disorder that may affect up to 1% of the world population. Morphological, electrophysiological, and neurophysiological studies suggest that the corpus callosum (CC), which is the largest portion of white matter in the human brain and responsible for inter-hemispheric communication, is altered in schizophrenia patients. Here, we employed mass spectrometry-based proteomics to investigate the molecular underpinnings of schizophrenia. Brain tissue samples were collected postmortem from nine schizophrenia patients and seven controls at the University of Heidelberg, Germany. Because the CC has a signaling role, we collected cytoplasmic (soluble) proteins and submitted them to nano-liquid chromatography-mass spectrometry (nano LC-MS/MS). Proteomes were quantified by label-free spectral counting. We identified 5678 unique peptides that corresponded to 1636 proteins belonging to 1512 protein families. Of those proteins, 65 differed significantly in expression: 28 were upregulated and 37 downregulated. Our data increased significantly the knowledge derived from an earlier proteomic study of the CC. Among the differentially expressed proteins are those associated with cell growth and maintenance, such as neurofilaments and tubulins; cell communication and signaling, such as 14-3-3 proteins; and oligodendrocyte function, such as myelin basic protein and myelin-oligodendrocyte glycoprotein. Additionally, 30 of the differentially expressed proteins were found previously in other proteomic studies in postmortem brains; this overlap in findings validates the present study and indicates that these proteins may be markers consistently associated with schizophrenia. Our findings increase the understanding of schizophrenia pathophysiology and may serve as a foundation for further treatment strategies.

  13. 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

  14. Plasma Corticosterone Activates SGK1 and Induces Morphological Changes in Oligodendrocytes in Corpus Callosum

    PubMed Central

    Miyata, Shingo; Koyama, Yoshihisa; Takemoto, Kana; Yoshikawa, Keiko; Ishikawa, Toshiko; Taniguchi, Manabu; Inoue, Kiyoshi; Aoki, Miwa; Hori, Osamu; Katayama, Taiichi; Tohyama, Masaya

    2011-01-01

    Repeated stressful events are known to be associated with onset of depression. Further, stress activates the hypothalamic–pituitary–adrenocortical (HPA) system by elevating plasma cortisol levels. However, little is known about the related downstream molecular pathway. In this study, by using repeated water-immersion and restraint stress (WIRS) as a stressor for mice, we attempted to elucidate the molecular pathway induced by elevated plasma corticosterone levels. We observed the following effects both, in vivo and in vitro: (1) repeated exposure to WIRS activates the 3-phosphoinositide-dependent protein kinase (PDK1)–serum glucocorticoid regulated kinase (SGK1)–N-myc downstream-regulated gene 1 (NDRG1)–adhesion molecule (i.e., N-cadherin, α-catenin, and β-catenin) stabilization pathway via an increase in plasma corticosterone levels; (2) the activation of this signaling pathway induces morphological changes in oligodendrocytes; and (3) after recovery from chronic stress, the abnormal arborization of oligodendrocytes and depression-like symptoms return to the control levels. Our data strongly suggest that these abnornalities of oligodendrocytes are possibly related to depression-like symptoms. PMID:21655274

  15. 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

    2016-08-09

    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.

  16. 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

  17. 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 Central

    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

  18. Self-referential and social cognition in a case of autism and agenesis of the corpus callosum

    PubMed Central

    2012-01-01

    Background While models of autism spectrum conditions (ASC) are emerging at the genetic level of analysis, clear models at higher levels of analysis, such as neuroanatomy, are lacking. Here we examine agenesis of the corpus callosum (AgCC) as a model at the level of neuroanatomy that may be relevant for understanding self-referential and social-cognitive difficulties in ASC. Methods We examined performance on a wide array of tests in self-referential and social-cognitive domains in a patient with both AgCC and a diagnosis of ASC. Tests included a depth-of-processing memory paradigm with self-referential and social-cognitive manipulations, self-report measures of self-consciousness, alexithymia, and empathy, as well as performance measures of first-person pronoun usage and mentalizing ability. The performance of the AgCC patient was compared to a group of individuals with ASC but without AgCC and with neurotypical controls. These comparison groups come from a prior study where group differences were apparent across many measures. We used bootstrapping to assess whether the AgCC patient exhibited scores that were within or outside the 95% bias-corrected and accelerated bootstrap confidence intervals observed in both comparison groups. Results Within the depth-of-processing memory paradigm, the AgCC patient showed decreased memory sensitivity that was more extreme than both comparison groups across all conditions. The patient’s most pronounced difficulty on this task emerged in the social-cognitive domain related to information-processing about other people. The patient was similar to the ASC group in benefiting less from self-referential processing compared to the control group. Across a variety of other self-referential (i.e. alexithymia, private self-consciousness) and social-cognitive measures (i.e. self-reported imaginative and perspective-taking subscales of empathy, mentalizing), the AgCC patient also showed more extreme scores than those observed for both of

  19. The K-Cl cotransporter KCC3 is mutant in a severe peripheral neuropathy associated with agenesis of the corpus callosum.

    PubMed

    Howard, Heidi C; Mount, David B; Rochefort, Daniel; Byun, Nellie; Dupré, Nicolas; Lu, Jianming; Fan, Xuemo; Song, Luyan; Rivière, Jean-Baptiste; Prévost, Claude; Horst, Jürgen; Simonati, Alessandro; Lemcke, Beate; Welch, Rick; England, Roger; Zhan, Frank Q; Mercado, Adriana; Siesser, William B; George, Alfred L; McDonald, Michael P; Bouchard, Jean-Pierre; Mathieu, Jean; Delpire, Eric; Rouleau, Guy A

    2002-11-01

    Peripheral neuropathy associated with agenesis of the corpus callosum (ACCPN) is a severe sensorimotor neuropathy associated with mental retardation, dysmorphic features and complete or partial agenesis of the corpus callosum. ACCPN is transmitted in an autosomal recessive fashion and is found at a high frequency in the province of Quebec, Canada. ACCPN has been previously mapped to chromosome 15q. The gene SLC12A6 (solute carrier family 12, member 6), which encodes the K+-Cl- transporter KCC3 and maps within the ACCPN candidate region, was screened for mutations in individuals with ACCPN. Four distinct protein-truncating mutations were found: two in the French Canadian population and two in non-French Canadian families. The functional consequence of the predominant French Canadian mutation (2436delG, Thr813fsX813) was examined by heterologous expression of wildtype and mutant KCC3 in Xenopus laevis oocytes; the truncated mutant is appropriately glycosylated and expressed at the cellular membrane, where it is non-functional. Mice generated with a targeted deletion of Slc12a6 have a locomotor deficit, peripheral neuropathy and a sensorimotor gating deficit, similar to the human disease. Our findings identify mutations in SLC12A6 as the genetic lesion underlying ACCPN and suggest a critical role for SLC12A6 in the development and maintenance of the nervous system.

  20. 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.

  1. Yokukansan normalizes glucocorticoid receptor protein expression in oligodendrocytes of the corpus callosum by regulating microRNA-124a expression after stress exposure.

    PubMed

    Shimizu, Shoko; Tanaka, Takashi; Tohyama, Masaya; Miyata, Shingo

    2015-05-01

    Stressful events are known to down-regulate expression levels of glucocorticoid receptors (GRs) in the brain. Recently, we reported that stressed mice with elevated plasma levels of corticosterone exhibit morphological changes in the oligodendrocytes of nerve fiber bundles, such as those in the corpus callosum. However, little is known about the molecular mechanism of GR expression regulation in oligodendrocytes after stress exposure. A previous report has suggested that GR protein levels might be regulated by microRNA (miR)-18 and/or -124a in the brain. In this study, we aimed to elucidate the GR regulation mechanism in oligodendrocytes and evaluate the effects of yokukansan (YKS), a Kampo medicine, on GR protein regulation. Acute exposure to stress increased plasma corticosterone levels, decreased GR protein expression, and increased miR-124a expression in the corpus callosum of adult male mice, though the GR mRNA and miR-18 expression levels were not significant changes. YKS normalized the stress-induced changes in the plasma corticosterone, GR protein, and miR124a expression levels. An oligodendrocyte primary culture study also showed that YKS down-regulated miR-124a, but not miR-18, expression levels in dexamethasone-treated cells. These results suggest that the down-regulation of miR124a expression might be involved in the normalization of stress-induced decreases in GR protein in oligodendrocytes by YKS. This effect may imply the molecular mechanisms underlying the ameliorative effects of YKS on psychological symptoms and stress-related behaviors.

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

    PubMed Central

    Branzoli, Francesca; Webb, Andrew; Sati, Pascal; Reich, Daniel S.; Ronen, Itamar

    2016-01-01

    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 3T and 7T. We investigated the inter- and intra-subject variability of empirical and modeled diffusion properties of tNAA [Davg(tNAA) and Dmodel(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 (CV) and repeatability coefficients (CR) for Davg(tNAA) and Dmodel(tNAA) were calculated for both 3T and 7T, with overall lower variability in the 7T 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 7T, whilst retaining low variability (CV ≈ 8%) for the tNAA diffusion measures. Power calculations for the estimation of Dmodel(tNAA) and Davg(tNAA) based on the suggested schemes show that less than 21 subjects per group are

  3. Gross morphology and morphometric sequelae in the hippocampus, fornix, and corpus callosum of patients with severe non-missile traumatic brain injury without macroscopically detectable lesions: a T1 weighted MRI study

    PubMed Central

    Tomaiuolo, F; Carlesimo, G; Di, P; Petrides, M; Fera, F; Bonanni, R; Formisano, R; Pasqualetti, P; Caltagirone, C

    2004-01-01

    Objective: The gross morphology and morphometry of the hippocampus, fornix, and corpus callosum in patients with severe non-missile traumatic brain injury (nmTBI) without obvious neuroradiological lesions was examined and the volumes of these structures were correlated with performance on memory tests. In addition, the predictability of the length of coma from the selected anatomical volumes was examined. Method: High spatial resolution T1 weighted MRI scans of the brain (1 mm3) and neuropsychological evaluations with standardised tests were performed at least 3 months after trauma in 19 patients. Results: In comparison with control subjects matched in terms of gender and age, volume reduction in the hippocampus, fornix, and corpus callosum of the nmTBI patients was quantitatively significant. The length of coma correlated with the volume reduction in the corpus callosum. Immediate free recall of word lists correlated with the volume of the fornix and the corpus callosum. Delayed recall of word lists and immediate recall of the Rey figure both correlated with the volume of the fornix. Delayed recall of the Rey figure correlated with the volume of the fornix and the right hippocampus. Conclusion: These findings demonstrate that in severe nmTBI without obvious neuroradiological lesions there is a clear hippocampal, fornix, and callosal volume reduction. The length of coma predicts the callosal volume reduction, which could be considered a marker of the severity of axonal loss. A few memory test scores correlated with the volumes of the selected anatomical structures. This relationship with memory performance may reflect the diffuse nature of the damage, leading to the disruption of neural circuits at multiple levels and the progressive neural degeneration occurring in TBI. PMID:15314123

  4. 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

  5. Loss of left-sided volitional movements caused by a combined lesion of the corpus callosum and right hemisphere:'initiation pseudohemiakinesia'.

    PubMed

    Yokoyama, K; Hasegawa, C; Kameyama, M

    2000-01-01

    We report a right-handed patient who showed a marked loss of unilateral volitional movements of the left limbs after the onset of a cerebral infarction in the combined territories of the right anterior and middle cerebral arteries. The same limbs retained their mobility in acts requiring bilateral sides of the body. This left-sided abnormal behavior resembled motor neglect resulting from lateralized brain damage. Behavioral and neuroradiological findings presented by this patient, however, suggested that callosal disconnection was definitely involved in this symptomatology. We postulate that in this patient, the diseased right hemisphere could no longer initiate movements of the left limbs despite its potential ability to realize them, and that the injured callosum prevented the intact left hemisphere from initiating unilateral voluntary movements of the left limbs. We suggest that this so far undescribed symptomatology be called 'initiation pseudohemiakinesia' in order to be distinguished from other rare forms of unilateral voluntary movements like motor neglect, extinction or directional hypokinesia.

  6. [Left-sided metamorphopsia of the face and simple objects caused by an infarction at the right side of the splenium of the corpus callosum].

    PubMed

    Nagaishi, Akiko; Narita, Tomoko; Gondo, Yuichiro; Nakane, Shunya; Fukudome, Takayasu; Matsuo, Hidenori

    2015-01-01

    A 78-year-old woman noticed that people's eyes and the right nasal foramens located in her left visual field looked smaller than those observed in the right. The woman reported no change in shape regarding facial outlines or scenic objects. Magnetic resonance imaging revealed an acute infarction of the right side of the splenium of the corpus callosum. Close examination revealed that her metamorphopsia affected the left side of her visual field, especially influencing facial components, particularly the eye. The woman had similar reactions to photographs of several kinds of animals, realistic portraits of humans, and caricatured humans. Meanwhile, presentings caricature human face at a 90° rotation elicited metamorphopsia in eyebrows located on the left side of a picture, but not the eyes. She also reported a change of shape or color tone for geometric objects. The patient's only symptom was metamorphopsia, and she did not show any other neurological defects such as callosal disconnection syndrome. Furthermore, objects that were affected by the patient's metamorphopsia (e.g. facial component especially the eye, and simple geometric figures) may be easy images to use in order to detect this type of distorted vision. PMID:26004257

  7. 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

  8. 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.

  9. 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.

  10. Stereotactic linac-based radiosurgery in the treatment of cerebral arteriovenous malformations located deep, involving corpus callosum, motor cortex, or brainstem

    SciTech Connect

    Zabel-du Bois, Angelika . E-mail: A.Zabel@dkfz-heidelberg.de; Milker-Zabel, Stefanie; Huber, Peter; Schlegel, Wolfgang; Debus, Juergen

    2006-03-15

    Purpose: To evaluate patient outcome and obliteration rates after radiosurgery (RS) for cerebral arteriovenous malformations (AVM) located deep, in the motor cortex or brainstem and those involving corpus callosum. Methods and Materials: This analysis is based on 65 patients. AVM classification according to Spetzler-Martin was 13 patients Grade 2, 39 Grade 3, 12 Grade 4, and 1 Grade 5. Median RS-based AVM score was 1.69. Median single dose was 18 Gy. Mean treatment volume was 5.2 cc (range, 0.2-26.5 cc). Forty patients (62%) experienced intracranial hemorrhage before RS. Median follow-up was 3.0 years. Results: Actuarial complete obliteration rate (CO) was 50% and 65% after 3 and 5 years, respectively. CO was significantly higher in AVM <3 cm (p < 0.02) and after doses >18 Gy (p < 0.009). Annual bleeding risk after RS was 4.7%, 3.4%, and 2.7% after 1, 2, and 3 years, respectively. AVM >3 cm (p < 0.01), AVM volume >4 cc (p < 0.009), and AVM score >1.5 (p < 0.02) showed a significant higher bleeding risk. Neurologic dysfunction improved, completely dissolved, or remained stable in 94% of patients. Conclusions: Surgically inaccessible AVM can be successfully treated using RS with acceptable obliteration rates and low risk for late morbidity. The risk of intracranial hemorrhage is reduced after RS and depends on RS-based AVM score.

  11. Abnormal function of the corpus luteum in some ewes with phyto-oestrogenic infertility.

    PubMed

    Adams, N R; Hearnshaw, H; Oldham, C M

    1981-01-01

    Ewes with permanent phyto-estrogenic infertility show oestrus less regularly than normal ewes, and the present study examines the extent to which this results from abnormal ovarian function. Forty-nine affected ewes and 53 controls were run with rams fitted with marking crayons and harnesses, and crayon marks were recorded and laparoscopy performed at weekly intervals for 3 weeks. Fewer affected ewes showed oestrus accompanied by ovulation (28 v. 49, P less than 0.001), and four of these affected ewes had a second ovulation during the experiment. More of the ovulations observed in affected ewes were unaccompanied by behavioural oestrus than in controls (8 out of 38 v. 2 out of 50; P less than 0.05). Six affected ewes had no corpus luteum or oestrus, and five of these had adhesions over the genitalia. Hydrops uteri in five other affected ewes was accompanied by prolonged maintenance of the corpus luteum. Some other abnormalities were also observed. In a second study, plasma progesterone concentrations were measured twice daily in 12 affected ewes which were run with rams. Five ewes had oestrous cycles of abnormal duration (two of more than 23 days, two of 21 days, and one of 11 days), and these were accompanied by plasma progesterone patterns different from those of the ewes with an oestrous cycle duration of 16-18 days. It is concluded that the irregular oestrous cycles in affected ewes are due mainly to abnormal life span and progesterone secretion by the corpus luteum, which in turn largely result from changes in the uterus. PMID:7196218

  12. Agenesis of the Corpus Callosum

    MedlinePlus

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  13. Occurrence of bilaterally independent epileptic spasms after a corpus callosotomy in West syndrome.

    PubMed

    Kobayashi, Katsuhiro; Endoh, Fumika; Toda, Yoshihiro; Oka, Makio; Baba, Hiroshi; Ohtsuka, Yoko; Yoshinaga, Harumi

    2016-01-01

    We report a patient with intractable West syndrome whose epileptic spasms (ESs) were initially bilaterally synchronous, as is typical; after a complete corpus callosotomy, however, bilaterally independent ESs originated in either hemisphere. Activity of probable cortical origin associated with ESs was detected by observing ictal gamma oscillations. Brain MRI revealed no structural abnormality before surgery. This case suggests that ESs with a hemispheric origin may appear generalized because of synchronizing effects in the corpus callosum in some patients.

  14. [Variants of the anterior circle of Willis. Anatomic and angiografic correlation and its implications in the surgery of intracranial aneurysms. (Acigos anterior cerebral artery, median artery of the corpus callosum and accessory middle cerebral artery)].

    PubMed

    Martínez, F; Spagnuolo, E; Calvo-Rubal, A; Laza, S; Sgarbi, N; Soria-Vargas, V R; Prinzo, H

    2004-12-01

    It is worlwide accepted that in almost 60% of cases, anatomical variants in the Circle of Willis can be found. Some of them are associated with vascular malformations such as aneurysms. The knowledge of these anatomical variants is of vital importance when facing surgery, being the aims to preserve arteries in unusual localisations, which when injured can determine invalidating sequelae. The authors have reviewed 192 cerebral hemispheres, finding three variants in the anterior Circle of Willis: Azigos anterior cerebral artery; Median artery of the corpus callosum and accessory middle cerebral artery. The authors make an anatomical description of the findings, their angiographical correlation, and describe the influence of these changes during surgery of aneurysms in the involved regions.

  15. Corpus callosum atrophy associated with the degree of cognitive decline in patients with Alzheimer's dementia or mild cognitive impairment: a meta-analysis of the region of interest structural imaging studies.

    PubMed

    Wang, Xu-Dong; Ren, Ming; Zhu, Min-Wei; Gao, Wen-Peng; Zhang, Jun; Shen, Hong; Lin, Zhi-Guo; Feng, Hong-Lin; Zhao, Chang-Jiu; Gao, Keming

    2015-04-01

    Individual structural neuroimaging studies of the corpus callosum (CC) in Alzheimer's disease (AD) and mild cognitive impairment (MCI) with the region of interest (ROI) analysis have yielded inconsistent findings. The aim of this study was to conduct a meta-analysis of structural imaging studies using ROI technique to measure the CC midsagittal area changes in patients with AD or MCI. Databases of PubMed, the Cochrane Library, the ISI Web of Science, and Science Direct from inception to June 2014 were searched with key words "corpus callosum" or "callosal", plus "Alzheimer's disease" or "mild cognitive impairment". Twenty-three studies with 603 patients with AD, 146 with MCI, and 638 healthy controls were included in this meta-analysis. Effect size was used to measure the difference between patients with AD or MCI and healthy controls. Significant callosal atrophy was found in MCI patients with an effect size of -0.36 (95% CI, -0.57 to -0.14; P = 0.001). The degree of the CC atrophy in mild AD was less severe than that in moderate AD with a mean effect size -0.69 (95% CI, -0.89 to -0.49) versus -0.92 (95% CI, -1.16 to -0.69), respectively. Comparing with healthy controls, patients with MCI had atrophy in the anterior portion of the CC (i.e., rostrum and genu). In contrast, patients with AD had atrophy in both anterior and posterior portions (i.e., splenium). These results suggest that callosal atrophy may be related to the degree of cognitive decline in patients with MCI and AD, and it may be used as a biomarker for patients with cognitive deficit even before meeting the criteria for AD.

  16. Three familial midline malformtion syndromes of the central nervous system: agenesis of the corpus callosum and anterior horn-cell disease; agenesis of cerebellar vermis; and atrophy of the cerebellar vermis.

    PubMed

    Andermann, E; Andermann, F; Joubert, M; Melançon, D; Karpati, G; Carpenter, S

    1975-01-01

    Three syndromes are presented in which major midline malformations of the central nervous system were associated with characteristic somatic and neurologic features in 2 or more sibs. The malformations may be suspected on clinical grouds but require confirmation by pneumoencephalography. In 3 French-Canadian sibships from the Saguenay-Lac St. Jean area of Quebec, patients with areflexia, muscular wasting and slowly progressive weakness in a paraparetic distribution were proved to have agenesis of the corpus callosum and anterior horn-cell disease, a syndrome not previously described. In another family, mental retardation, ataxia and episodic hyperpnea were associated with agenesis of the cerebellar vermis in 4 sibs. In yet another French-Canadian family, atrophy of the cerebellar vermis was associated with mental retardation, ataxia and a mild pyramidal syndrome. Because malformations of this nature are usually considered sporadic or multifactorial in origin, recognition of these specific clinical syndromes with probable autosomal recessive inheritance is important from the point of view of genetic counseling and prevention. PMID:1227532

  17. A new locus (SPG46) maps to 9p21.2-q21.12 in a Tunisian family with a complicated autosomal recessive hereditary spastic paraplegia with mental impairment and thin corpus callosum.

    PubMed

    Boukhris, Amir; Feki, Imed; Elleuch, Nizar; Miladi, Mohamed Imed; Boland-Augé, Anne; Truchetto, Jérémy; Mundwiller, Emeline; Jezequel, Nadia; Zelenika, Diana; Mhiri, Chokri; Brice, Alexis; Stevanin, Giovanni

    2010-10-01

    Hereditary spastic paraplegia (HSP) with thin corpus callosum (TCC) and mental impairment is a frequent subtype of complicated HSP, often inherited as an autosomal recessive (AR) trait. It is clear from molecular genetic analyses that there are several underlying causes of this syndrome, with at least six genetic loci identified to date. However, SPG11 and SPG15 are the two major genes for this entity. To map the responsible gene in a large AR-HSP-TCC family of Tunisian origin, we investigated a consanguineous family with a diagnosis of AR-HSP-TCC excluded for linkage to the SPG7, SPG11, SPG15, SPG18, SPG21, and SPG32 loci. A genome-wide scan was undertaken using 6,090 SNP markers covering all chromosomes. The phenotypic presentation in five patients was suggestive of a complex HSP that associated an early-onset spastic paraplegia with mild handicap, mental deterioration, congenital cataract, cerebellar signs, and TCC. The genome-wide search identified a single candidate region on chromosome 9, exceeding the LOD score threshold of +3. Fine mapping using additional markers narrowed the candidate region to a 45.1-Mb interval (15.4 cM). Mutations in three candidate genes were excluded. The mapping of a novel AR-HSP-TCC locus further demonstrates the extensive genetic heterogeneity of this condition. We propose that testing for this locus should be performed, after exclusion of mutations in SPG11 and SPG15 genes, in AR-HSP-TCC families, especially when cerebellar ataxia and cataract are present.

  18. Delineation of a deletion region critical for corpus callosal abnormalities in chromosome 1q43–q44

    PubMed Central

    Nagamani, Sandesh C Sreenath; Erez, Ayelet; Bay, Carolyn; Pettigrew, Anjana; Lalani, Seema R; Herman, Kristin; Graham, Brett H; Nowaczyk, Malgorzata JM; Proud, Monica; Craigen, William J; Hopkins, Bobbi; Kozel, Beth; Plunkett, Katie; Hixson, Patricia; Stankiewicz, Pawel; Patel, Ankita; Cheung, Sau Wai

    2012-01-01

    Submicroscopic deletions involving chromosome 1q43–q44 result in cognitive impairment, microcephaly, growth restriction, dysmorphic features, and variable involvement of other organ systems. A consistently observed feature in patients with this deletion are the corpus callosal abnormalities (CCAs), ranging from thinning and hypoplasia to complete agenesis. Previous studies attempting to delineate the critical region for CCAs have yielded inconsistent results. We conducted a detailed clinical and molecular characterization of seven patients with deletions of chromosome 1q43–q44. Using array comparative genomic hybridization, we mapped the size, extent, and genomic content of these deletions. Four patients had CCAs, and shared the smallest region of overlap that contains only three protein coding genes, CEP170, SDCCAG8, and ZNF238. One patient with a small deletion involving SDCCAG8 and AKT3, and another patient with an intragenic deletion of AKT3 did not have any CCA, implying that the loss of these two genes is unlikely to be the cause of CCA. CEP170 is expressed extensively in the brain, and encodes for a protein that is a component of the centrosomal complex. ZNF238 is involved in control of neuronal progenitor cells and survival of cortical neurons. Our results rule out the involvement of AKT3, and implicate CEP170 and/or ZNF238 as novel genes causative for CCA in patients with a terminal 1q deletion. PMID:21934713

  19. 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…

  20. Children with New Onset Epilepsy Exhibit Diffusion Abnormalities in Cerebral White Matter in the Absence of Volumetric Differences

    PubMed Central

    Hutchinson, Elizabeth; Pulsipher, Dalin; Dabbs, Kevin; Myers y Gutierrez, Adan; Sheth, Raj; Jones, Jana; Seidenberg, Michael; Meyerand, Elizabeth; Hermann, Bruce

    2010-01-01

    SUMMARY The purpose of this investigation was to examine the diffusion properties of cerebral white matter in children with recent onset epilepsy (n=19) compared to healthy controls (n=11). Subjects underwent DTI with quantification of mean diffusion (MD), fractional anisotropy (FA), axial diffusivity (Dax) and radial diffusivity (Drad) for regions of interest including anterior and posterior corpus callosum, fornix, cingulum, and internal and external capsules. Quantitative volumetrics were also performed for the corpus callosum and its subregions (anterior, midbody and posterior) and total lobar white and gray matter for the frontal, parietal, temporal and occipital lobes. The results demonstrated no group differences in total lobar gray or white matter volumes or volume of the corpus callosum and its subregions, but did show reduced FA and increased Drad in the posterior corpus callosum and cingulum. These results provide the earliest indication of microstructural abnormality in cerebral white matter among children with idiopathic epilepsies. This abnormality occurs in the context of normal volumetrics and suggests disruption in myelination processes. PMID:20044239

  1. Periventricular nodular heterotopia, frontonasal encephalocele, corpus callosal dysgenesis and arachnoid cyst: A constellation of abnormalities in a child with epilepsy.

    PubMed

    Krishnan, Prasad; Chattopadhyay, Arijit; Saha, Manash

    2014-01-01

    A 7-year-old male child presented with poorly controlled generalized tonic-clonic seizures. On examination, he was mentally retarded, deaf and had a swelling at the root on the nose. Computed tomography scan done previously revealed a left temporal arachnoid cyst (AC) due to which he was referred for surgery. However, magnetic resonance imaging revealed a constellation of abnormalities - all of which could be responsible for his seizures. The combination of periventricular nodular heterotopias with encepaholcele is rarely described in the literature, and more infrequently so its combination with AC and callosal dysgenesis - the Chudley-Mccullough syndrome. We describe the case and review relevant literature on this subject.

  2. Periventricular nodular heterotopia, frontonasal encephalocele, corpus callosal dysgenesis and arachnoid cyst: A constellation of abnormalities in a child with epilepsy

    PubMed Central

    Krishnan, Prasad; Chattopadhyay, Arijit; Saha, Manash

    2014-01-01

    A 7-year-old male child presented with poorly controlled generalized tonic-clonic seizures. On examination, he was mentally retarded, deaf and had a swelling at the root on the nose. Computed tomography scan done previously revealed a left temporal arachnoid cyst (AC) due to which he was referred for surgery. However, magnetic resonance imaging revealed a constellation of abnormalities – all of which could be responsible for his seizures. The combination of periventricular nodular heterotopias with encepaholcele is rarely described in the literature, and more infrequently so its combination with AC and callosal dysgenesis – the Chudley-Mccullough syndrome. We describe the case and review relevant literature on this subject. PMID:25624936

  3. Association between chronic stress-induced structural abnormalities in Ranvier nodes and reduced oligodendrocyte activity in major depression

    PubMed Central

    Miyata, Shingo; Taniguchi, Manabu; Koyama, Yoshihisa; Shimizu, Shoko; Tanaka, Takashi; Yasuno, Fumihiko; Yamamoto, Akihide; Iida, Hidehiro; Kudo, Takashi; Katayama, Taiichi; Tohyama, Masaya

    2016-01-01

    Repeated stressful events are associated with the onset of major depressive disorder (MDD). We previously showed oligodendrocyte (OL)-specific activation of the serum/glucocorticoid-regulated kinase (SGK)1 cascade, increased expression of axon-myelin adhesion molecules, and elaboration of the oligodendrocytic arbor in the corpus callosum of chronically stressed mice. In the current study, we demonstrate that the nodes and paranodes of Ranvier in the corpus callosum were narrower in these mice. Chronic stress also led to diffuse redistribution of Caspr and Kv 1.1 and decreased the activity in white matter, suggesting a link between morphological changes in OLs and inhibition of axonal activity. OL primary cultures subjected to chronic stress resulted in SGK1 activation and translocation to the nucleus, where it inhibited the transcription of metabotropic glutamate receptors (mGluRs). Furthermore, the cAMP level and membrane potential of OLs were reduced by chronic stress exposure. We showed by diffusion tensor imaging that the corpus callosum of patients with MDD exhibited reduced fractional anisotropy, reflecting compromised white matter integrity possibly caused by axonal damage. Our findings suggest that chronic stress disrupts the organization of the nodes of Ranvier by suppressing mGluR activation in OLs, and that specific white matter abnormalities are closely associated with MDD onset. PMID:26976207

  4. Communication as Corpus Callosum: A Reorganization of Knowledge.

    ERIC Educational Resources Information Center

    Cooper, Thomas

    1993-01-01

    Argues that communication, as an academic discipline and as an ongoing process, can be seen as a bridge between the two hemispheres within the liberal arts brain. Discusses unique changes within communication in the twentieth century. Maintains that communication theory may serve as one new method of connecting the liberal arts. (SR)

  5. 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…

  6. Brain abnormalities in murderers indicated by positron emission tomography.

    PubMed

    Raine, A; Buchsbaum, M; LaCasse, L

    1997-09-15

    Murderers pleading not guilty by reason of insanity (NGRI) are thought to have brain dysfunction, but there have been no previous studies reporting direct measures of both cortical and subcortical brain functioning in this specific group. Positron emission tomography brain imaging using a continuous performance challenge task was conducted on 41 murderers pleading not guilty by reason of insanity and 41 age- and sex-matched controls. Murderers were characterized by reduced glucose metabolism in the prefrontal cortex, superior parietal gyrus, left angular gyrus, and the corpus callosum, while abnormal asymmetries of activity (left hemisphere lower than right) were also found in the amygdala, thalamus, and medial temporal lobe. These preliminary findings provide initial indications of a network of abnormal cortical and subcortical brain processes that may predispose to violence in murderers pleading NGRI.

  7. Abnormal Asymmetry of Brain Connectivity in Schizophrenia

    PubMed Central

    Ribolsi, Michele; Daskalakis, Zafiris J.; Siracusano, Alberto; Koch, Giacomo

    2014-01-01

    Recently, a growing body of data has revealed that beyond a dysfunction of connectivity among different brain areas in schizophrenia patients (SCZ), there is also an abnormal asymmetry of functional connectivity compared with healthy subjects. The loss of the cerebral torque and the abnormalities of gyrification, with an increased or more complex cortical folding in the right hemisphere may provide an anatomical basis for such aberrant connectivity in SCZ. Furthermore, diffusion tensor imaging studies have shown a significant reduction of leftward asymmetry in some key white-matter tracts in SCZ. In this paper, we review the studies that investigated both structural brain asymmetry and asymmetry of functional connectivity in healthy subjects and SCZ. From an analysis of the existing literature on this topic, we can hypothesize an overall generally attenuated asymmetry of functional connectivity in SCZ compared to healthy controls. Such attenuated asymmetry increases with the duration of the disease and correlates with psychotic symptoms. Finally, we hypothesize that structural deficits across the corpus callosum may contribute to the abnormal asymmetry of intra-hemispheric connectivity in schizophrenia. PMID:25566030

  8. Diffusion Tensor MR Imaging Evaluation of Callosal Abnormalities in Schizophrenia: A Meta-Analysis

    PubMed Central

    Zhuo, Chuanjun; Liu, Mei; Wang, Lina; Tian, Hongjun; Tang, Jinsong

    2016-01-01

    Widespread white matter (WM) abnormalities have been found in patients with schizophrenia. Corpus callosum (CC) is the key area that connects the left and right brain hemispheres. However, the results of studies considering different subregions of the CC as regions of interest in patients with schizophrenia have been inconsistent. To obtain a more consistent evaluation of the diffusion characteristics change of the corpus callosum (CC) related to schizophrenia. A meta-analysis involving fractional anisotropy (FA) values in the CC of 729 schizophrenic subjects and 682 healthy controls from 22 studies was conducted. Overall FA values in the CC of the schizophrenic group were less than that of the healthy control group [weighted mean difference (WMD) = -0.021,P< 0.001]. So were the FA values in the genus region (WMD = -0.019, P< 0.001) and the splenium region (WMD = -0.020, P< 0.001) of the CC respectively. The FA reduction was also significant in subjects with chronic schizophrenia (WMD = -0.032, P< 0.001) and first-episode schizophrenia (WMD = -0.014, P = 0.001). In present study, we demonstrated an overall FA decrease in the CC of schizophrenic patients. In the two subgroup analyses of the genu vs splenium region and chronic vs first-episode schizophrenia, the decrease of all groups was significant. Further studies with more homogenous populations and standardized DTI protocols are needed to confirm and extend these findings. PMID:27536773

  9. Diffusion Tensor MR Imaging Evaluation of Callosal Abnormalities in Schizophrenia: A Meta-Analysis.

    PubMed

    Zhuo, Chuanjun; Liu, Mei; Wang, Lina; Tian, Hongjun; Tang, Jinsong

    2016-01-01

    Widespread white matter (WM) abnormalities have been found in patients with schizophrenia. Corpus callosum (CC) is the key area that connects the left and right brain hemispheres. However, the results of studies considering different subregions of the CC as regions of interest in patients with schizophrenia have been inconsistent. To obtain a more consistent evaluation of the diffusion characteristics change of the corpus callosum (CC) related to schizophrenia. A meta-analysis involving fractional anisotropy (FA) values in the CC of 729 schizophrenic subjects and 682 healthy controls from 22 studies was conducted. Overall FA values in the CC of the schizophrenic group were less than that of the healthy control group [weighted mean difference (WMD) = -0.021,P< 0.001]. So were the FA values in the genus region (WMD = -0.019, P< 0.001) and the splenium region (WMD = -0.020, P< 0.001) of the CC respectively. The FA reduction was also significant in subjects with chronic schizophrenia (WMD = -0.032, P< 0.001) and first-episode schizophrenia (WMD = -0.014, P = 0.001). In present study, we demonstrated an overall FA decrease in the CC of schizophrenic patients. In the two subgroup analyses of the genu vs splenium region and chronic vs first-episode schizophrenia, the decrease of all groups was significant. Further studies with more homogenous populations and standardized DTI protocols are needed to confirm and extend these findings. PMID:27536773

  10. White matter abnormalities in schizophrenia and schizotypal personality disorder.

    PubMed

    Lener, Marc S; Wong, Edmund; Tang, Cheuk Y; Byne, William; Goldstein, Kim E; Blair, Nicholas J; Haznedar, M Mehmet; New, Antonia S; Chemerinski, Eran; Chu, King-Wai; Rimsky, Liza S; Siever, Larry J; Koenigsberg, Harold W; Hazlett, Erin A

    2015-01-01

    Prior diffusion tensor imaging (DTI) studies examining schizotypal personality disorder (SPD) and schizophrenia, separately have shown that compared with healthy controls (HCs), patients show frontotemporal white matter (WM) abnormalities. This is the first DTI study to directly compare WM tract coherence with tractography and fractional anisotropy (FA) across the schizophrenia spectrum in a large sample of demographically matched HCs (n = 55), medication-naive SPD patients (n = 49), and unmedicated/never-medicated schizophrenia patients (n = 22) to determine whether (a) frontal-striatal-temporal WM tract abnormalities in schizophrenia are similar to, or distinct from those observed in SPD; and (b) WM tract abnormalities are associated with clinical symptom severity indicating a common underlying pathology across the spectrum. Compared with both the HC and SPD groups, schizophrenia patients showed WM abnormalities, as indexed by lower FA in the temporal lobe (inferior longitudinal fasciculus) and cingulum regions. SPD patients showed lower FA in the corpus callosum genu compared with the HC group, but this regional abnormality was more widespread in schizophrenia patients. Across the schizophrenia spectrum, greater WM disruptions were associated with greater symptom severity. Overall, frontal-striatal-temporal WM dysconnectivity is attenuated in SPD compared with schizophrenia patients and may mitigate the emergence of psychosis.

  11. 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.

  12. White matter abnormalities of microstructure and physiological noise in schizophrenia

    PubMed Central

    Newman, Sharlene D.; Kent, Jerillyn S.; Bolbecker, Amanda; Klaunig, Mallory J.; O'Donnell, Brian F.; Puce, Aina; Hetrick, William P.

    2015-01-01

    White matter abnormalities in schizophrenia have been revealed by many imaging techniques and analysis methods. One of the findings by diffusion tensor imaging is a decrease in fractional anisotropy (FA), which is an indicator of white matter integrity. On the other hand, elevation of metabolic rate in white matter was observed from positron emission tomography (PET) studies. In this report, we aim to compare the two structural and functional effects on the same subjects. Our comparison is based on the hypothesis that signal fluctuation in white matter is associated with white matter functional activity. We examined the variance of the signal in resting state fMRI and found significant differences between individuals with schizophrenia and non-psychiatric controls specifically in white matter tissue. Controls showed higher temporal signal-to-noise ratios clustered in regions including temporal, frontal, and parietal lobes, cerebellum, corpus callosum, superior longitudinal fasciculus, and other major white matter tracts. These regions with higher temporal signal-to-noise ratio agree well with those showing higher metabolic activity reported by studies using PET. The results suggest that individuals with schizophrenia tend to have higher functional activity in white matter in certain brain regions relative to healthy controls. Despite some overlaps, the distinct regions for physiological noise are different from those for FA derived from diffusion tensor imaging, and therefore provide a unique angle to explore potential mechanisms to white matter abnormality. PMID:25560665

  13. Inborn errors of metabolism: a cause of abnormal brain development.

    PubMed

    Nissenkorn, A; Michelson, M; Ben-Zeev, B; Lerman-Sagie, T

    2001-05-22

    Brain malformations are caused by a disruption in the sequence of normal development by various environmental or genetic factors. By modifying the intrauterine milieu, inborn errors of metabolism may cause brain dysgenesis. However, this association is typically described in single case reports. The authors review the relationship between brain dysgenesis and specific inborn errors of metabolism. Peroxisomal disorders and fatty acid oxidation defects can produce migration defects. Pyruvate dehydrogenase deficiency, nonketotic hyperglycinemia, and maternal phenylketonuria preferentially cause a dysgenetic corpus callosum. Abnormal metabolism of folic acid causes neural tube defects, whereas defects in cholesterol metabolism may produce holoprosencephaly. Various mechanisms have been proposed to explain abnormal brain development in inborn errors of metabolism: production of a toxic or energy-deficient intrauterine milieu, modification of the content and function of membranes, or disturbance of the normal expression of intrauterine genes responsible for morphogenesis. The recognition of a metabolic disorder as the cause of the brain malformation has implications for both the care of the patient and for genetic counseling to prevent recurrence in subsequent pregnancies. PMID:11383558

  14. Abnormal neurodevelopment, neurosignaling and behaviour in Npas3-deficient mice.

    PubMed

    Brunskill, Eric W; Ehrman, Lisa A; Williams, Michael T; Klanke, Justin; Hammer, Daniel; Schaefer, Tori L; Sah, Renu; Dorn, Gerald W; Potter, S Steven; Vorhees, Charles V

    2005-09-01

    Npas3 is a member of the bHLH-PAS superfamily of transcription factors that is expressed broadly in the developing neuroepithelium. To study the function of this gene, mice deficient in Npas3 were generated and characterized. Npas3-/- mice were growth-retarded and exhibited developmental brain abnormalities that included a reduction in size of the anterior hippocampus, hypoplasia of the corpus callosum and enlargement of the ventricles. A number of behavioural abnormalities were identified in Npas3-/- mice including locomotor hyperactivity, subtle gait defects, impairment of prepulse inhibition of acoustic startle, deficit in recognition memory and altered anxiety-related responses. Characterization of neurosignaling pathways using several pharmacological agents revealed dysfunctional glutamate, dopamine and serotonin neurotransmitter signaling. Consistent with these findings, we identified a significant alteration in cortical PSD-95 expression, a PDZ-containing protein that has been shown to be involved in postsynaptic signal transduction. Together, our observations indicate an important role for Npas3 in controlling normal brain development and neurosignaling pathways. PMID:16190882

  15. White matter abnormalities of microstructure and physiological noise in schizophrenia.

    PubMed

    Cheng, Hu; Newman, Sharlene D; Kent, Jerillyn S; Bolbecker, Amanda; Klaunig, Mallory J; O'Donnell, Brian F; Puce, Aina; Hetrick, William P

    2015-12-01

    White matter abnormalities in schizophrenia have been revealed by many imaging techniques and analysis methods. One of the findings by diffusion tensor imaging is a decrease in fractional anisotropy (FA), which is an indicator of white matter integrity. On the other hand, elevation of metabolic rate in white matter was observed from positron emission tomography (PET) studies. In this report, we aim to compare the two structural and functional effects on the same subjects. Our comparison is based on the hypothesis that signal fluctuation in white matter is associated with white matter functional activity. We examined the variance of the signal in resting state fMRI and found significant differences between individuals with schizophrenia and non-psychiatric controls specifically in white matter tissue. Controls showed higher temporal signal-to-noise ratios clustered in regions including temporal, frontal, and parietal lobes, cerebellum, corpus callosum, superior longitudinal fasciculus, and other major white matter tracts. These regions with higher temporal signal-to-noise ratio agree well with those showing higher metabolic activity reported by studies using PET. The results suggest that individuals with schizophrenia tend to have higher functional activity in white matter in certain brain regions relative to healthy controls. Despite some overlaps, the distinct regions for physiological noise are different from those for FA derived from diffusion tensor imaging, and therefore provide a unique angle to explore potential mechanisms to white matter abnormality.

  16. Multimodal voxel-based meta-analysis of white matter abnormalities in obsessive-compulsive disorder.

    PubMed

    Radua, Joaquim; Grau, Mar; van den Heuvel, Odile A; Thiebaut de Schotten, Michel; Stein, Dan J; Canales-Rodríguez, Erick J; Catani, Marco; Mataix-Cols, David

    2014-06-01

    White matter (WM) abnormalities have long been suspected in obsessive-compulsive disorder (OCD) but the available evidence has been inconsistent. We conducted the first multimodal meta-analysis of WM volume (WMV) and fractional anisotropy (FA) studies in OCD. All voxel-wise studies comparing WMV or FA between patients with OCD and healthy controls in the PubMed, ScienceDirect, Google Scholar, Web of Knowledge and Scopus databases were retrieved. Manual searches were also conducted and authors were contacted soliciting additional data. Thirty-four data sets were identified, of which 22 met inclusion criteria (five of them unpublished; comprising 537 adult and pediatric patients with OCD and 575 matched healthy controls). Whenever possible, raw statistical parametric maps were also obtained from the authors. Peak and raw WMV and FA data were combined using novel multimodal meta-analytic methods implemented in effect-size signed differential mapping. Patients with OCD showed widespread WM abnormalities, but findings were particularly robust in the anterior midline tracts (crossing between anterior parts of cingulum bundle and body of corpus callosum), which showed both increased WMV and decreased FA, possibly suggesting an increase of fiber crossing in these regions. This finding was also observed when the analysis was limited to adult participants, and especially pronounced in samples with a higher proportion of medicated patients. Therefore, patients with OCD may have widespread WM abnormalities, particularly evident in anterior midline tracts, although these changes might be, at least in part, attributable to the effects of therapeutic drugs.

  17. Delineation of candidate genes responsible for structural brain abnormalities in patients with terminal deletions of chromosome 6q27

    PubMed Central

    Peddibhotla, Sirisha; Nagamani, Sandesh CS; Erez, Ayelet; Hunter, Jill V; Holder Jr, J Lloyd; Carlin, Mary E; Bader, Patricia I; Perras, Helene MF; Allanson, Judith E; Newman, Leslie; Simpson, Gayle; Immken, LaDonna; Powell, Erin; Mohanty, Aaron; Kang, Sung-Hae L; Stankiewicz, Pawel; Bacino, Carlos A; Bi, Weimin; Patel, Ankita; Cheung, Sau W

    2015-01-01

    Patients with terminal deletions of chromosome 6q present with structural brain abnormalities including agenesis of corpus callosum, hydrocephalus, periventricular nodular heterotopia, and cerebellar malformations. The 6q27 region harbors genes that are important for the normal development of brain and delineation of a critical deletion region for structural brain abnormalities may lead to a better genotype–phenotype correlation. We conducted a detailed clinical and molecular characterization of seven unrelated patients with deletions involving chromosome 6q27. All patients had structural brain abnormalities. Using array comparative genomic hybridization, we mapped the size, extent, and genomic content of these deletions. The smallest region of overlap spans 1.7 Mb and contains DLL1, THBS2, PHF10, and C6orf70 (ERMARD) that are plausible candidates for the causation of structural brain abnormalities. Our study reiterates the importance of 6q27 region in normal development of brain and helps identify putative genes in causation of structural brain anomalies. PMID:24736736

  18. Delineation of candidate genes responsible for structural brain abnormalities in patients with terminal deletions of chromosome 6q27.

    PubMed

    Peddibhotla, Sirisha; Nagamani, Sandesh C S; Erez, Ayelet; Hunter, Jill V; Holder, J Lloyd; Carlin, Mary E; Bader, Patricia I; Perras, Helene M F; Allanson, Judith E; Newman, Leslie; Simpson, Gayle; Immken, LaDonna; Powell, Erin; Mohanty, Aaron; Kang, Sung-Hae L; Stankiewicz, Pawel; Bacino, Carlos A; Bi, Weimin; Patel, Ankita; Cheung, Sau W

    2015-01-01

    Patients with terminal deletions of chromosome 6q present with structural brain abnormalities including agenesis of corpus callosum, hydrocephalus, periventricular nodular heterotopia, and cerebellar malformations. The 6q27 region harbors genes that are important for the normal development of brain and delineation of a critical deletion region for structural brain abnormalities may lead to a better genotype-phenotype correlation. We conducted a detailed clinical and molecular characterization of seven unrelated patients with deletions involving chromosome 6q27. All patients had structural brain abnormalities. Using array comparative genomic hybridization, we mapped the size, extent, and genomic content of these deletions. The smallest region of overlap spans 1.7 Mb and contains DLL1, THBS2, PHF10, and C6orf70 (ERMARD) that are plausible candidates for the causation of structural brain abnormalities. Our study reiterates the importance of 6q27 region in normal development of brain and helps identify putative genes in causation of structural brain anomalies.

  19. Gray matter and white matter abnormalities in online game addiction.

    PubMed

    Weng, Chuan-Bo; Qian, Ruo-Bing; Fu, Xian-Ming; Lin, Bin; Han, Xiao-Peng; Niu, Chao-Shi; Wang, Ye-Han

    2013-08-01

    Online game addiction (OGA) has attracted greater attention as a serious public mental health issue. However, there are only a few brain magnetic resonance imaging studies on brain structure about OGA. In the current study, we used voxel-based morphometry (VBM) analysis and tract-based spatial statistics (TBSS) to investigate the microstructural changes in OGA and assessed the relationship between these morphology changes and the Young's Internet Addiction Scale (YIAS) scores within the OGA group. Compared with healthy subjects, OGA individuals showed significant gray matter atrophy in the right orbitofrontal cortex, bilateral insula, and right supplementary motor area. According to TBSS analysis, OGA subjects had significantly reduced FA in the right genu of corpus callosum, bilateral frontal lobe white matter, and right external capsule. Gray matter volumes (GMV) of the right orbitofrontal cortex, bilateral insula and FA values of the right external capsule were significantly positively correlated with the YIAS scores in the OGA subjects. Our findings suggested that microstructure abnormalities of gray and white matter were present in OGA subjects. This finding may provide more insights into the understanding of the underlying neural mechanisms of OGA.

  20. Language Planning: Corpus Planning.

    ERIC Educational Resources Information Center

    Baldauf, Richard B., Jr.

    1989-01-01

    Focuses on the historical and sociolinguistic studies that illuminate corpus planning processes. These processes are broken down and discussed under two categories: those related to the establishment of norms, referred to as codification, and those related to the extension of the linguistic functions of language, referred to as elaboration. (60…

  1. Wnt-induced calcium signaling mediates axon growth and guidance in the developing corpus callosum.

    PubMed

    Hutchins, B Ian; Li, Li; Kalil, Katherine

    2012-01-10

    Wnt5a gradients guide callosal axons by repulsion through Ryk receptors in vivo. We recently found that Wnt5a repels cortical axons and promotes axon outgrowth through calcium signaling in vitro. Here, using cortical slices, we show that Wnt5a signals through Ryk to guide and promote outgrowth of callosal axons after they cross the midline. Calcium transient frequencies in callosal growth cones positively correlate with axon outgrowth rates in vitro. In cortical slices, calcium release through inositol 1,4,5-trisphosphate (IP(3)) receptors and calcium entry through transient receptor potential channels modulate axon growth and guidance. Knocking down Ryk inhibits calcium signaling in cortical axons, reduces rates of axon outgrowth subsequent to midline crossing, and causes axon guidance defects. Calcium- and calmodulin-dependent protein kinase II (CaMKII) is required downstream of Wnt-induced calcium signaling for postcrossing callosal axon growth and guidance. Taken together, these results suggest that growth and guidance of postcrossing callosal axons by Wnt-Ryk-calcium signaling involves axon repulsion through CaMKII.

  2. "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,…

  3. 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...

  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. 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...

  6. 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…

  7. 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)…

  8. Remyelination of the Corpus Callosum by Olfactory Ensheathing Cell in an Experimental Model of Multiple Sclerosis.

    PubMed

    Azimi Alamouti, Mohammad; Bakhtiyari, Mehrdad; Moradi, Fatemeh; Mokhtari, Tahmineh; Hedayatpour, Azim; Zafari, Fariba; Barbarestani, Mohammad

    2015-01-01

    Multiple Sclerosis (MS) causes loss of the myelin sheath, which leads to loss of neurons. Regeneration of myelin sheath stimulates axon regeneration and neurons' survival. In this study, olfactory ensheathing cell (OEC) transplantation is investigated to restore myelin sheath in an experimental model of MS in male mice.OECs were isolated from the olfactory mucosa of seven-day-old infant rats and cultured. Then, cells were evaluated and approved by flow cytometry by p75 and GFAP markers. A total of 32 mice (C57BL /6) were studied in four groups; 1) without any treatment (control), 2) Sham (receiving PBS), 3) MS model and 4) MS and OEC transplantation. MS was induced by adding Cuprizon in the diet of animals for six weeks. After the expiration of 20 days, histologic analysis was performed with approval of the presence of cells in the graft area and the removal of myelin and myelin regeneration with two types of luxal fast blue (LFB) staining and immunohistochemistry. The purity of the cells ensheathing the olfactory was 90%. There was a significant difference in Myelin percentage of PBS and OEC recipient groups (P≤0.05). MBP and PLP of the myelin sheath in the group receiving OECs were more than MS group.According to the findings, in MS model MBP and PLP of the myelin sheath is reduced. In the group receiving OECs, it was returned to a normal level significantly compared to the sham group received only PBS significant differences were observed. The OECs transplantation can improve myelin restoration.

  9. 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…

  10. Abnormal brain magnetic resonance imaging in two patients with Smith-Magenis syndrome.

    PubMed

    Maya, Idit; Vinkler, Chana; Konen, Osnat; Kornreich, Liora; Steinberg, Tamar; Yeshaya, Josepha; Latarowski, Victoria; Shohat, Mordechai; Lev, Dorit; Baris, Hagit N

    2014-08-01

    Smith-Magenis syndrome (SMS) is a clinically recognizable contiguous gene syndrome ascribed to an interstitial deletion in chromosome 17p11.2. Seventy percent of SMS patients have a common deletion interval spanning 3.5 megabases (Mb). Clinical features of SMS include characteristic mild dysmorphic features, ocular anomalies, short stature, brachydactyly, and hypotonia. SMS patients have a unique neurobehavioral phenotype that includes intellectual disability, self-injurious behavior and severe sleep disturbance. Little has been reported in the medical literature about anatomical brain anomalies in patients with SMS. Here we describe two patients with SMS caused by the common deletion in 17p11.2 diagnosed using chromosomal microarray (CMA). Both patients had a typical clinical presentation and abnormal brain magnetic resonance imaging (MRI) findings. One patient had subependymal periventricular gray matter heterotopia, and the second had a thin corpus callosum, a thin brain stem and hypoplasia of the cerebellar vermis. This report discusses the possible abnormal MRI images in SMS and reviews the literature on brain malformations in SMS. Finally, although structural brain malformations in SMS patients are not a common feature, we suggest baseline routine brain imaging in patients with SMS in particular, and in patients with chromosomal microdeletion/microduplication syndromes in general. Structural brain malformations in these patients may affect the decision-making process regarding their management.

  11. Prenatal diagnosis of foetuses with congenital abnormalities and duplication of the MECP2 region.

    PubMed

    Fu, Fang; Liu, Huan-ling; Li, Ru; Han, Jin; Yang, Xin; Min, Pan; Zhen, Li; Zhang, Yong-ling; Xie, Gui-e; Lei, Ting-ying; Li, Yan; Li, Jian; Li, Dong-zhi; Liao, Can

    2014-08-10

    MECP2 duplication results in a well-recognised syndrome in 100% of affected male children; this syndrome is characterised by severe neurodevelopmental disabilities and recurrent infections. However, no sonographic findings have been reported for affected foetuses, and prenatal molecular diagnosis has not been possible for this disease due to lack of prenatal clinical presentation. In this study, we identified a small duplication comprising the MECP2 and L1CAM genes in the Xq28 region in a patient from a family with severe X-linked mental retardation and in a prenatal foetus with brain structural abnormalities. Using high-resolution chromosome microarray analysis (CMA) to screen 108 foetuses with congenital structural abnormalities, we identified additional three foetuses with the MECP2 duplication. Our study indicates that ventriculomegaly, hydrocephalus, agenesis of the corpus callosum, choroid plexus cysts, foetal growth restriction and hydronephrosis might be common ultrasound findings in prenatal foetuses with the MECP2 duplication and provides the first set of prenatal cases with MECP2 duplication, the ultrasonographic phenotype described in these patients will help to recognise the foetuses with possible MECP2 duplication and prompt the appropriate molecular testing.

  12. Prenatal diagnosis of foetuses with congenital abnormalities and duplication of the MECP2 region.

    PubMed

    Fu, Fang; Liu, Huan-ling; Li, Ru; Han, Jin; Yang, Xin; Min, Pan; Zhen, Li; Zhang, Yong-ling; Xie, Gui-e; Lei, Ting-ying; Li, Yan; Li, Jian; Li, Dong-zhi; Liao, Can

    2014-08-10

    MECP2 duplication results in a well-recognised syndrome in 100% of affected male children; this syndrome is characterised by severe neurodevelopmental disabilities and recurrent infections. However, no sonographic findings have been reported for affected foetuses, and prenatal molecular diagnosis has not been possible for this disease due to lack of prenatal clinical presentation. In this study, we identified a small duplication comprising the MECP2 and L1CAM genes in the Xq28 region in a patient from a family with severe X-linked mental retardation and in a prenatal foetus with brain structural abnormalities. Using high-resolution chromosome microarray analysis (CMA) to screen 108 foetuses with congenital structural abnormalities, we identified additional three foetuses with the MECP2 duplication. Our study indicates that ventriculomegaly, hydrocephalus, agenesis of the corpus callosum, choroid plexus cysts, foetal growth restriction and hydronephrosis might be common ultrasound findings in prenatal foetuses with the MECP2 duplication and provides the first set of prenatal cases with MECP2 duplication, the ultrasonographic phenotype described in these patients will help to recognise the foetuses with possible MECP2 duplication and prompt the appropriate molecular testing. PMID:24914495

  13. The relationship between white matter abnormalities and cognitive functions in new-onset juvenile myoclonic epilepsy.

    PubMed

    Ekmekci, Burcu; Bulut, Hacı Taner; Gümüştaş, Funda; Yıldırım, Adem; Kuştepe, Ali

    2016-09-01

    Diffusion tensor imaging (DTI) has revealed evidence of subcortical white matter abnormalities in the frontal area in juvenile myoclonic epilepsy (JME). Decreased fractional anisotropy (FA) and increased mean diffusivity (MD) in the corticothalamic pathway have been detected in adult patients with JME. It has been demonstrated that, in adult patients with JME, frontal dysfunction is related to subcortical white matter damage and decreased volume in frontal cortical gray matter and the thalamus. Many studies have focused on adult patients. Twenty-four patients and 28 controls were evaluated. The group with JME had significantly worse results for the word fluency, trail-B, and Stroop tests that assessed executive functions. A significant decrease in FA values in the dorsolateral prefrontal cortex (DLPFC), the supplementary motor area (SMA), the right thalamus, the posterior cingulate, the corpus callosum anterior, the corona radiata, and the middle frontal white matter (MFWM) and an increase in ADC values in patients with JME were detected. The correlation between FA values in DLPFC and the letter fluency test results was positive, and the correlation with the Stroop and trail-B test results was negative. We found a negative correlation between SMA, anterior thalamus, and MFWM FA values and the trail-B test results and a positive correlation between the SMA, anterior thalamus, and MFWM FA values and the letter fluency test results. We detected white matter and gray matter abnormalities in patients with new-onset JME using DTI. In addition, we determined the relationship between cognitive deficit and microstructural abnormalities by evaluating the correlation between the neuropsychological test battery results and DTI parameters. We evaluated newly diagnosed patients with JME in our study. That leads us to believe that microstructural abnormalities exist from the very beginning of the disease and that they result from the genetic basis of the disease.

  14. Abnormal morphology of myelin and axon pathology in murine models of multiple sclerosis.

    PubMed

    Bando, Yoshio; Nomura, Taichi; Bochimoto, Hiroki; Murakami, Koichi; Tanaka, Tatsuhide; Watanabe, Tsuyoshi; Yoshida, Shigetaka

    2015-02-01

    Demyelination and axonal damage are responsible for neurological deficits in multiple sclerosis (MS), an inflammatory demyelinating disease of the central nervous system. However, the pathology of axonal damage in MS is not fully understood. In this study, histological analysis of morphological changes of axonal organelles during demyelination in murine models was investigated by scanning electron microscopy (SEM) using an osmium-maceration method. In cuprizone-induced demyelination, SEM showed typical morphology of demyelination in the corpus callosum of mouse brain. In contrast, SEM displayed variations in ultrastructural abnormalities of myelin structures and axonal organelles in spinal cord white matter of experimental autoimmune encephalomyelitis (EAE) mice, an animal model of MS. Myelin detachment and excessive myelin formation were observed as typical morphological myelin abnormalities in EAE. In addition, well-developed axoplasmic reticulum-like structures and accumulated mitochondria were observed in tortuous degenerating/degenerated axons and the length of mitochondria in axons of EAE spinal cord was shorter compared with naïve spinal cord. Immunohistochemistry also revealed dysfunction of mitochondrial fusion/fission machinery in EAE spinal cord axons. Moreover, the number of Y-shaped mitochondria was significantly increased in axons of the EAE spinal cord. Axonal morphologies in myelin basic protein-deficient shiverer mice were similar to those in EAE. However, shiverer mice had "tortuous" (S-curve shaped mitochondria) and larger mitochondria compared with wild-type and EAE mice. Lastly, analysis of human MS patient autopsied brains also demonstrated abnormal myelin structures in demyelinating lesions. These results indicate that morphological abnormalities of myelin and axonal organelles play important role on the pathogenesis of axonal injury in demyelinating diseases.

  15. Habeas Corpus and "Enemy Combatants"

    ERIC Educational Resources Information Center

    Pereira, Carolyn; Chavkin, Nisan

    2008-01-01

    The writ of habeas corpus has been a critical tool for balancing the rights of individuals with the government's responsibility to protect the nation's welfare. In this article, the authors discuss the writ of habeas corpus and how it affects the federal government and hundreds of prisoners who are held as enemy combatants. Elementary, middle, and…

  16. [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

  17. Diffusion Tensor Imaging for Assessing Brain Gray and White Matter Abnormalities in a Feline Model of α-Mannosidosis.

    PubMed

    Kumar, Manoj; Duda, Jeff T; Yoon, Sea Young; Bagel, Jessica; O'Donnell, Patricia; Vite, Charles; Pickup, Stephen; Gee, James C; Wolfe, John H; Poptani, Harish

    2016-01-01

    α-Mannosidosis (AMD) is an autosomal recessively inherited lysosomal storage disorder affecting brain function and structure. We performed ex vivo and in vivo diffusion tensor imaging (DTI) on the brains of AMD-affected cats to assess gray and white matter abnormalities. A multi-atlas approach was used to generate a brain template to process the ex vivo DTI data. The probabilistic label method was used to measure fractional anisotropy (FA), mean diffusivity, axial diffusivity, and radial diffusivity values from gray and white matter regions from ex vivo DTI. Regional analysis from various regions of the gray matter (frontal cortex, cingulate gyrus, caudate nucleus, hippocampus, thalamus, and occipital cortex), and white matter (corpus callosum, corticospinal tract, cerebral peduncle, external and internal capsule) was also performed on both ex vivo and in vivo DTI. Ex vivo DTI revealed significantly reduced FA from both gray and white matter regions in AMD-affected cats compared to controls. Significantly reduced FA was also observed from in vivo DTI of AMD-affected cats compared to controls, with lower FA values observed in all white matter regions. We also observed significantly increased axial and radial diffusivity values in various gray and white matter regions in AMD cats from both ex vivo and in vivo DTI data. Imaging findings were correlated with histopathologic analyses suggesting that DTI studies can further aid in the characterization of AMD by assessing the microstructural abnormalities in both white and gray matter.

  18. Concomitant Fractional Anisotropy and Volumetric Abnormalities in Temporal Lobe Epilepsy: Cross-Sectional Evidence for Progressive Neurologic Injury

    PubMed Central

    Gerdes, Jan S.; Weber, Bernd; Deppe, Michael

    2012-01-01

    Background In patients with temporal lobe epilepsy and associated hippocampal sclerosis (TLEhs) there are brain abnormalities extending beyond the presumed epileptogenic zone as revealed separately in conventional magnetic resonance imaging (MRI) and MR diffusion tensor imaging (DTI) studies. However, little is known about the relation between macroscopic atrophy (revealed by volumetric MRI) and microstructural degeneration (inferred by DTI). Methodology/Principal Findings For 62 patients with unilateral TLEhs and 68 healthy controls, we determined volumes and mean fractional anisotropy (FA) of ipsilateral and contralateral brain structures from T1-weighted and DTI data, respectively. We report significant volume atrophy and FA alterations of temporal lobe, subcortical and callosal regions, which were more diffuse and bilateral in patients with left TLEhs relative to right TLEhs. We observed significant relationships between volume loss and mean FA, particularly of the thalamus and putamen bilaterally. When corrected for age, duration of epilepsy was significantly correlated with FA loss of an anatomically plausible route - including ipsilateral parahippocampal gyrus and temporal lobe white matter, the thalamus bilaterally, and posterior regions of the corpus callosum that contain temporal lobe fibres - that may be suggestive of progressive brain degeneration in response to recurrent seizures. Conclusions/Significance Chronic TLEhs is associated with interrelated DTI-derived and volume-derived brain degenerative abnormalities that are influenced by the duration of the disorder and the side of seizure onset. This work confirms previously contradictory findings by employing multi-modal imaging techniques in parallel in a large sample of patients. PMID:23071638

  19. Dido mutations trigger perinatal death and generate brain abnormalities and behavioral alterations in surviving adult mice

    PubMed Central

    Villares, Ricardo; Gutiérrez, Julio; Fütterer, Agnes; Trachana, Varvara; Gutiérrez del Burgo, Fernando; Martínez-A, Carlos

    2015-01-01

    Nearly all vertebrate cells have a single cilium protruding from their surface. This threadlike organelle, once considered vestigial, is now seen as a pivotal element for detection of extracellular signals that trigger crucial morphogenetic pathways. We recently proposed a role for Dido3, the main product of the death inducer-obliterator (dido) gene, in histone deacetylase 6 delivery to the primary cilium [Sánchez de Diego A, et al. (2014) Nat Commun 5:3500]. Here we used mice that express truncated forms of Dido proteins to determine the link with cilium-associated disorders. We describe dido mutant mice with high incidence of perinatal lethality and distinct neurodevelopmental, morphogenetic, and metabolic alterations. The anatomical abnormalities were related to brain and orofacial development, consistent with the known roles of primary cilia in brain patterning, hydrocephalus incidence, and cleft palate. Mutant mice that reached adulthood showed reduced life expectancy, brain malformations including hippocampus hypoplasia and agenesis of corpus callosum, as well as neuromuscular and behavioral alterations. These mice can be considered a model for the study of ciliopathies and provide information for assessing diagnosis and therapy of genetic disorders linked to the deregulation of primary cilia. PMID:25825751

  20. Universum Inference and Corpus Homogeneity

    NASA Astrophysics Data System (ADS)

    Vogel, Carl; Lynch, Gerard; Janssen, Jerom

    Universum Inference is re-interpreted for assessment of corpus homogeneity in computational stylometry. Recent stylometric research quantifies strength of characterization within dramatic works by assessing the homogeneity of corpora associated with dramatic personas. A methodological advance is suggested to mitigate the potential for the assessment of homogeneity to be achieved by chance. Baseline comparison analysis is constructed for contributions to debates by nonfictional participants: the corpus analyzed consists of transcripts of US Presidential and Vice-Presidential debates from the 2000 election cycle. The corpus is also analyzed in translation to Italian, Spanish and Portuguese. Adding randomized categories makes assessments of homogeneity more conservative.

  1. Connectome Signatures of Neurocognitive Abnormalities in Euthymic Bipolar I Disorder

    PubMed Central

    Ajilore, Olusola; Vizueta, Nathalie; Walshaw, Patricia; Zhan, Liang; Leow, Alex; Altshuler, Lori L.

    2015-01-01

    Objectives Connectomics have allowed researchers to study integrative patterns of neural connectivity in humans. Yet, it is unclear how connectomics may elucidate structure-function relationships in bipolar I disorder (BPI). Expanding on our previous structural connectome study, here we used an overlapping sample with additional psychometric and fMRI data to relate structural connectome properties to both fMRI signals and cognitive performance. Methods 42 subjects completed a neuropsychological (NP) battery covering domains of processing speed, verbal memory, working memory, and cognitive flexibility. 32 subjects also had fMRI data performing a Go/NoGo task. Results Bipolar participants had lower NP performance across all domains, but only working memory reached statistical significance. In BPI participants, processing speed was significantly associated with both white matter integrity (WMI) in the corpus callosum and interhemispheric network integration. Mediation models further revealed that the relationship between interhemispheric integration and processing speed was mediated by WMI, and processing speed mediated the relationship between WMI and working memory. Bipolar subjects had significantly decreased BA47 activation during NoGo vs. Go. Significant predictors of BA47 fMRI activations during the Go/NoGo task were its nodal path length (left hemisphere) and its nodal clustering coefficient (right hemisphere). Conclusions This study suggests that structural connectome changes underlie abnormalities in fMRI activation and cognitive performance in euthymic BPI subjects. Results support that BA47 structural connectome changes may be a trait marker for BPI. Future studies are needed to determine if these “connectome signatures” may also confer a biological risk and/or serve as predictors of relapse. PMID:26228398

  2. A voxel-based morphometry (VBM) analysis of regional grey and white matter volume abnormalities within the speech production network of children who stutter

    PubMed Central

    Beal, Deryk S.; Gracco, Vincent L.; Brettschneider, Jane; Kroll, Robert M.; De Nil, Luc F.

    2012-01-01

    It is well documented that neuroanatomical differences exist between adults who stutter and their fluently speaking peers. Specifically, adults who stutter have been found to have more grey matter volume (GMV) in speech relevant regions including inferior frontal gyrus, insula and superior temporal gyrus (Beal et al., 2007; Song et al., 2007). Despite stuttering having its onset in childhood only one study has investigated the neuroanatomical differences between children who do and do not stutter. Chang et al. (2008) reported children who stutter had less GMV in the bilateral inferior frontal gyri and middle temporal gyrus relative to fluently speaking children. Thus it appears that children who stutter present with unique neuroanatomical abnormalities as compared to those of adults who stutter. In order to better understand the neuroanatomical correlates of stuttering earlier in its development, near the time of onset, we used voxel-based morphometry to examine volumetric differences between 11 children who stutter and 11 fluent children. Children who stutter had less GMV in the bilateral inferior frontal gyri and left putamen but more GMV in right Rolandic operculum and superior temporal gyrus relative to fluent children. Children who stutter also had less white matter volume bilaterally in the forceps minor of the corpus callosum. We discuss our findings of widespread anatomic abnormalities throughout the cortical network for speech motor control within the context of the speech motor skill limitations identified in people who stutter (Namasivayam and van Lieshout, 2008; Smits-Bandstra et al., 2006). PMID:23140891

  3. Large national series of patients with Xq28 duplication involving MECP2: Delineation of brain MRI abnormalities in 30 affected patients.

    PubMed

    El Chehadeh, Salima; Faivre, Laurence; Mosca-Boidron, Anne-Laure; Malan, Valérie; Amiel, Jeanne; Nizon, Mathilde; Touraine, Renaud; Prieur, Fabienne; Pasquier, Laurent; Callier, Patrick; Lefebvre, Mathilde; Marle, Nathalie; Dubourg, Christèle; Julia, Sophie; Sarret, Catherine; Francannet, Christine; Laffargue, Fanny; Boespflug-Tanguy, Odile; David, Albert; Isidor, Bertrand; Le Caignec, Cédric; Vigneron, Jacqueline; Leheup, Bruno; Lambert, Laetitia; Philippe, Christophe; Cuisset, Jean-Marie; Andrieux, Joris; Plessis, Ghislaine; Toutain, Annick; Goldenberg, Alice; Cormier-Daire, Valérie; Rio, Marlène; Bonnefont, Jean-Paul; Thevenon, Julien; Echenne, Bernard; Journel, Hubert; Afenjar, Alexandra; Burglen, Lydie; Bienvenu, Thierry; Addor, Marie-Claude; Lebon, Sébastien; Martinet, Danièle; Baumann, Clarisse; Perrin, Laurence; Drunat, Séverine; Jouk, Pierre-Simon; Devillard, Françoise; Coutton, Charles; Lacombe, Didier; Delrue, Marie-Ange; Philip, Nicole; Moncla, Anne; Badens, Catherine; Perreton, Nathalie; Masurel, Alice; Thauvin-Robinet, Christel; Des Portes, Vincent; Guibaud, Laurent

    2016-01-01

    Xq28 duplications encompassing MECP2 have been described in male patients with a severe neurodevelopmental disorder associated with hypotonia and spasticity, severe learning disability, stereotyped movements, and recurrent pulmonary infections. We report on standardized brain magnetic resonance imaging (MRI) data of 30 affected patients carrying an Xq28 duplication involving MECP2 of various sizes (228 kb to 11.7 Mb). The aim of this study was to seek recurrent malformations and attempt to determine whether variations in imaging features could be explained by differences in the size of the duplications. We showed that 93% of patients had brain MRI abnormalities such as corpus callosum abnormalities (n = 20), reduced volume of the white matter (WM) (n = 12), ventricular dilatation (n = 9), abnormal increased hyperintensities on T2-weighted images involving posterior periventricular WM (n = 6), and vermis hypoplasia (n = 5). The occipitofrontal circumference varied considerably between >+2SD in five patients and <-2SD in four patients. Among the nine patients with dilatation of the lateral ventricles, six had a duplication involving L1CAM. The only patient harboring bilateral posterior subependymal nodular heterotopia also carried an FLNA gene duplication. We could not demonstrate a correlation between periventricular WM hyperintensities/delayed myelination and duplication of the IKBKG gene. We thus conclude that patients with an Xq28 duplication involving MECP2 share some similar but non-specific brain abnormalities. These imaging features, therefore, could not constitute a diagnostic clue. The genotype-phenotype correlation failed to demonstrate a relationship between the presence of nodular heterotopia, ventricular dilatation, WM abnormalities, and the presence of FLNA, L1CAM, or IKBKG, respectively, in the duplicated segment.

  4. Large national series of patients with Xq28 duplication involving MECP2: Delineation of brain MRI abnormalities in 30 affected patients.

    PubMed

    El Chehadeh, Salima; Faivre, Laurence; Mosca-Boidron, Anne-Laure; Malan, Valérie; Amiel, Jeanne; Nizon, Mathilde; Touraine, Renaud; Prieur, Fabienne; Pasquier, Laurent; Callier, Patrick; Lefebvre, Mathilde; Marle, Nathalie; Dubourg, Christèle; Julia, Sophie; Sarret, Catherine; Francannet, Christine; Laffargue, Fanny; Boespflug-Tanguy, Odile; David, Albert; Isidor, Bertrand; Le Caignec, Cédric; Vigneron, Jacqueline; Leheup, Bruno; Lambert, Laetitia; Philippe, Christophe; Cuisset, Jean-Marie; Andrieux, Joris; Plessis, Ghislaine; Toutain, Annick; Goldenberg, Alice; Cormier-Daire, Valérie; Rio, Marlène; Bonnefont, Jean-Paul; Thevenon, Julien; Echenne, Bernard; Journel, Hubert; Afenjar, Alexandra; Burglen, Lydie; Bienvenu, Thierry; Addor, Marie-Claude; Lebon, Sébastien; Martinet, Danièle; Baumann, Clarisse; Perrin, Laurence; Drunat, Séverine; Jouk, Pierre-Simon; Devillard, Françoise; Coutton, Charles; Lacombe, Didier; Delrue, Marie-Ange; Philip, Nicole; Moncla, Anne; Badens, Catherine; Perreton, Nathalie; Masurel, Alice; Thauvin-Robinet, Christel; Des Portes, Vincent; Guibaud, Laurent

    2016-01-01

    Xq28 duplications encompassing MECP2 have been described in male patients with a severe neurodevelopmental disorder associated with hypotonia and spasticity, severe learning disability, stereotyped movements, and recurrent pulmonary infections. We report on standardized brain magnetic resonance imaging (MRI) data of 30 affected patients carrying an Xq28 duplication involving MECP2 of various sizes (228 kb to 11.7 Mb). The aim of this study was to seek recurrent malformations and attempt to determine whether variations in imaging features could be explained by differences in the size of the duplications. We showed that 93% of patients had brain MRI abnormalities such as corpus callosum abnormalities (n = 20), reduced volume of the white matter (WM) (n = 12), ventricular dilatation (n = 9), abnormal increased hyperintensities on T2-weighted images involving posterior periventricular WM (n = 6), and vermis hypoplasia (n = 5). The occipitofrontal circumference varied considerably between >+2SD in five patients and <-2SD in four patients. Among the nine patients with dilatation of the lateral ventricles, six had a duplication involving L1CAM. The only patient harboring bilateral posterior subependymal nodular heterotopia also carried an FLNA gene duplication. We could not demonstrate a correlation between periventricular WM hyperintensities/delayed myelination and duplication of the IKBKG gene. We thus conclude that patients with an Xq28 duplication involving MECP2 share some similar but non-specific brain abnormalities. These imaging features, therefore, could not constitute a diagnostic clue. The genotype-phenotype correlation failed to demonstrate a relationship between the presence of nodular heterotopia, ventricular dilatation, WM abnormalities, and the presence of FLNA, L1CAM, or IKBKG, respectively, in the duplicated segment. PMID:26420639

  5. White matter abnormalities and impaired attention abilities in children born very preterm.

    PubMed

    Murray, Andrea L; Thompson, Deanne K; Pascoe, Leona; Leemans, Alexander; Inder, Terrie E; Doyle, Lex W; Anderson, Jacqueline F I; Anderson, Peter J

    2016-01-01

    While attention impairments are commonly observed in very preterm (<32weeks' gestational age) children, neuroanatomical correlates of these difficulties are unclear. We aimed to determine whether the microstructural organization of key white matter tracts thought to be involved in attention (cingulum bundle, superior longitudinal fasciculi, reticular activating system, and corpus callosum) were altered in very preterm children compared with term-born controls. We also aimed to determine whether alterations in microstructural organization of these tracts were associated with attention functioning in very preterm children. One hundred and forty-nine very preterm children and 36 term-born controls underwent neuroimaging and assessment of their attention abilities at 7years. Constrained spherical deconvolution and probabilistic tractography was used to identify the key white matter tracts. Altered microstructural organization and reduced tract volume within reticular activating system and corpus callosum were found in the very preterm group compared with the control group. Diffusion and volume changes in the cingulum bundle, superior longitudinal fasciculi, reticular activating system, and corpus callosum were related to variations in attention functioning in the very preterm children. These findings emphasize that white matter tract integrity is associated with later attentional abilities in very preterm children.

  6. Corpus-based Customization for an Ontology

    SciTech Connect

    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.

  7. 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... RELATIONS LITIGATION Reporting Legal Proceedings to HQDA § 516.20 Habeas Corpus. (a) General. A soldier may file a writ of habeas corpus to challenge his continued custody (usually in a post...

  8. 32 CFR 516.20 - Habeas Corpus.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 3 2013-07-01 2013-07-01 false Habeas Corpus. 516.20 Section 516.20 National... RELATIONS LITIGATION Reporting Legal Proceedings to HQDA § 516.20 Habeas Corpus. (a) General. A soldier may file a writ of habeas corpus to challenge his continued custody (usually in a post...

  9. Developing an International Corpus of Creative English

    ERIC Educational Resources Information Center

    Hassall, Peter John

    2006-01-01

    This paper proposes an International Corpus of Creative English (ICCE) as a worldwide corpus particularly suitable for implementation in countries which have tertiary institutions with well-defined populations of students possessing similar cultural and/or linguistic backgrounds. The ICCE is contextualized as a world Englishes corpus with…

  10. Progressive Wallerian Degeneration of the Corpus Callosal Splenium in a Patient with Alexia Without Agraphia: Advanced MR Findings.

    PubMed

    Gandhi, Kriti; Gillihan, Laura; Wozniak, Marcella A; Zhuo, Jiachen; Raghavan, Prashant

    2014-12-01

    The corpus callosal splenium is an uncommon location for Wallerian degeneration (WD), which may be mistaken for new pathology on magnetic resonance imaging (MRI). We describe the case of a 69-year-old woman with a left posterior cerebral artery infarct in whom progressive WD of the splenium of the corpus callosum seen on MRI was misinterpreted as new infarction or neoplasm. We address how magnetic resonance spectroscopy, perfusion MRI, diffusion tensor MRI, and serial imaging were utilized in establishing the correct diagnosis. Interestingly, the patient also presented with alexia without agraphia, which has never been reported in association with splenial WD. It is conceivable that WD affected critical splenial association fibers resulting in this uncommon dissociation syndrome. PMID:25489886

  11. 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...

  12. 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…

  13. 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…

  14. Improved acquisition of left-right response differentiation in the rat following section of the corpus callosum.

    PubMed

    Noonan, M; Axelrod, S

    1991-12-20

    Split-brained rats learned a left-right response differentiation in a water maze significantly faster than rats with sham surgery. It is unlikely that this superiority resulted from improvement in performance variables since callosotomized rats did not differ significantly from sham operates in speed of acquisition of a brightness discrimination in the same apparatus. Additionally, callosotomy likewise had no effect on the acquisition of a water-maze task requiring consistent unilateral responses. The superiority of the callosotomized animals in forming the left-right response differentiation supports a hypothesis implicating the forebrain commissures in left-right confusion.

  15. Congenital Brain Abnormalities and Zika Virus: What the Radiologist Can Expect to See Prenatally and Postnatally.

    PubMed

    Soares de Oliveira-Szejnfeld, Patricia; Levine, Deborah; Melo, Adriana Suely de Oliveira; Amorim, Melania Maria Ramos; Batista, Alba Gean M; Chimelli, Leila; Tanuri, Amilcar; Aguiar, Renato Santana; Malinger, Gustavo; Ximenes, Renato; Robertson, Richard; Szejnfeld, Jacob; Tovar-Moll, Fernanda

    2016-10-01

    Purpose To document the imaging findings associated with congenital Zika virus infection as found in the Instituto de Pesquisa in Campina Grande State Paraiba (IPESQ) in northeastern Brazil, where the congenital infection has been particularly severe. Materials and Methods From June 2015 to May 2016, 438 patients were referred to the IPESQ for rash occurring during pregnancy or for suspected fetal central nervous system abnormality. Patients who underwent imaging at IPESQ were included, as well as those with documented Zika virus infection in fluid or tissue (n = 17, confirmed infection cohort) or those with brain findings suspicious for Zika virus infection, with intracranial calcifications (n = 28, presumed infection cohort). Imaging examinations included 12 fetal magnetic resonance (MR) examinations, 42 postnatal brain computed tomographic examinations, and 11 postnatal brain MR examinations. Images were reviewed by four radiologists, with final opinion achieved by means of consensus. Results Brain abnormalities seen in confirmed (n = 17) and presumed (n = 28) congenital Zika virus infections were similar, with ventriculomegaly in 16 of 17 (94%) and 27 of 28 (96%) infections, respectively; abnormalities of the corpus callosum in 16 of 17 (94%) and 22 of 28 (78%) infections, respectively; and cortical migrational abnormalities in 16 of 17 (94%) and 28 of 28 (100%) infections, respectively. Although most fetuses underwent at least one examination that showed head circumference below the 5th percentile, head circumference could be normal in the presence of severe ventriculomegaly (seen in three fetuses). Intracranial calcifications were most commonly seen at the gray matter-white matter junction, in 15 of 17 (88%) and 28 of 28 (100%) confirmed and presumed infections, respectively. The basal ganglia and/or thalamus were also commonly involved with calcifications in 11 of 17 (65%) and 18 of 28 (64%) infections, respectively. The skull frequently had a collapsed

  16. Meiotic abnormalities

    SciTech Connect

    1993-12-31

    Chapter 19, describes meiotic abnormalities. These include nondisjunction of autosomes and sex chromosomes, genetic and environmental causes of nondisjunction, misdivision of the centromere, chromosomally abnormal human sperm, male infertility, parental age, and origin of diploid gametes. 57 refs., 2 figs., 1 tab.

  17. Quetiapine Inhibits Microglial Activation by Neutralizing Abnormal STIM1-Mediated Intercellular Calcium Homeostasis and Promotes Myelin Repair in a Cuprizone-Induced Mouse Model of Demyelination

    PubMed Central

    Wang, Hanzhi; Liu, Shubao; Tian, Yanping; Wu, Xiyan; He, Yangtao; Li, Chengren; Namaka, Michael; Kong, Jiming; Li, Hongli; Xiao, Lan

    2015-01-01

    Microglial activation has been considered as a crucial process in the pathogenesis of neuroinflammation and psychiatric disorders. Several antipsychotic drugs (APDs) have been shown to display inhibitory effects on microglial activation in vitro, possibly through the suppression of elevated intracellular calcium (Ca2+) concentration. However, the exact underlying mechanisms still remain elusive. In this study, we aimed to investigate the inhibitory effects of quetiapine (Que), an atypical APD, on microglial activation. We utilized a chronic cuprizone (CPZ)-induced demyelination mouse model to determine the direct effect of Que on microglial activation. Our results showed that treatment with Que significantly reduced recruitment and activation of microglia/macrophage in the lesion of corpus callosum and promoted remyelination after CPZ withdrawal. Our in vitro studies also confirmed the direct effect of Que on lipopolysaccharide (LPS)-induced activation of microglial N9 cells, whereby Que significantly inhibited the release of nitric oxide (NO) and tumor necrosis factor α (TNF-α). Moreover, we demonstrated that pretreatment with Que, neutralized the up-regulation of STIM1 induced by LPS and declined both LPS and thapsigargin (Tg)-induced store-operated Ca2+ entry (SOCE). Finally, we found that pretreatment with Que significantly reduced the translocation of nuclear factor kappa B (NF-κB) p65 subunit from cytoplasm to nuclei in LPS-activated primary microglial cells. Overall, our data suggested that Que may inhibit microglial activation by neutralization of the LPS-induced abnormal STIM1-mediated intercellular calcium homeostasis. PMID:26732345

  18. Craniofacial Abnormalities

    MedlinePlus

    ... of the skull and face. Craniofacial abnormalities are birth defects of the face or head. Some, like cleft ... palate, are among the most common of all birth defects. Others are very rare. Most of them affect ...

  19. Chromosome Abnormalities

    MedlinePlus

    ... decade, newer techniques have been developed that allow scientists and doctors to screen for chromosomal abnormalities without using a microscope. These newer methods compare the patient's DNA to a normal DNA ...

  20. Walking abnormalities

    MedlinePlus

    ... include: Arthritis of the leg or foot joints Conversion disorder (a psychological disorder) Foot problems (such as a ... injuries. For an abnormal gait that occurs with conversion disorder, counseling and support from family members are strongly ...

  1. Nail abnormalities

    MedlinePlus

    Beau's lines; Fingernail abnormalities; Spoon nails; Onycholysis; Leukonychia; Koilonychia; Brittle nails ... Just like the skin, the fingernails tell a lot about your health: ... the fingernail. These lines can occur after illness, injury to ...

  2. 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...

  3. 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…

  4. Corpus-Based Investigations of Language Use.

    ERIC Educational Resources Information Center

    Biber, Douglas; And Others

    1996-01-01

    Examines a representative text corpus to gain insights into language structure and use and to open new areas of linguistic inquiry. Various illustrations are presented that provide a glimpse into the value of corpus-based investigations for increasing one's understanding of language use and imparting insights important for designing effective…

  5. 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…

  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. A voxel-based morphometry (VBM) analysis of regional grey and white matter volume abnormalities within the speech production network of children who stutter.

    PubMed

    Beal, Deryk S; Gracco, Vincent L; Brettschneider, Jane; Kroll, Robert M; De Nil, Luc F

    2013-09-01

    It is well documented that neuroanatomical differences exist between adults who stutter and their fluently speaking peers. Specifically, adults who stutter have been found to have more grey matter volume (GMV) in speech relevant regions including inferior frontal gyrus, insula and superior temporal gyrus (Beal et al., 2007; Song et al., 2007). Despite stuttering having its onset in childhood only one study has investigated the neuroanatomical differences between children who do and do not stutter. Chang et al. (2008) reported children who stutter had less GMV in the bilateral inferior frontal gyri and middle temporal gyrus relative to fluently speaking children. Thus it appears that children who stutter present with unique neuroanatomical abnormalities as compared to those of adults who stutter. In order to better understand the neuroanatomical correlates of stuttering earlier in its development, near the time of onset, we used voxel-based morphometry to examine volumetric differences between 11 children who stutter and 11 fluent children. Children who stutter had less GMV in the bilateral inferior frontal gyri and left putamen but more GMV in right Rolandic operculum and superior temporal gyrus relative to fluent children. Children who stutter also had less white matter volume bilaterally in the forceps minor of the corpus callosum. We discuss our findings of widespread anatomic abnormalities throughout the cortical network for speech motor control within the context of the speech motor skill limitations identified in people who stutter (Namasivayam and van Lieshout, 2008; Smits-Bandstra et al., 2006).

  8. White matter microstructural abnormalities in girls with chromosome 22q11.2 deletion syndrome, Fragile X or Turner syndrome as evidenced by diffusion tensor imaging

    PubMed Central

    Villalon, Julio; Jahanshad, Neda; Beaton, Elliott; Toga, Arthur W.; Thompson, Paul M.; Simon, Tony J.

    2014-01-01

    Children with chromosome 22q11.2 Deletion Syndrome (22q11.2DS), Fragile X Syndrome (FXS), or Turner Syndrome (TS) are considered to belong to distinct genetic groups, as each disorder is caused by separate genetic alterations. Even so, they have similar cognitive and behavioral dysfunctions, particularly in visuospatial and numerical abilities. To assess evidence for common underlying neural microstructural alterations, we set out to determine whether these groups have partially overlapping white matter abnormalities, relative to typically developing controls. We scanned 101 female children between 7 and 14 years old: 25 with 22q11.2DS, 18 with FXS, 17 with TS, and 41 aged-matched controls using diffusion tensor imaging (DTI). Anisotropy and diffusivity measures were calculated and all brain scans were nonlinearly aligned to population and site-specific templates. We performed voxel-based statistical comparisons of the DTI-derived metrics between each disease group and the controls, while adjusting for age. Girls with 22q11.2DS showed lower fractional anisotropy (FA) than controls in the association fibers of the superior and inferior longitudinal fasciculi, the splenium of the corpus callosum, and the corticospinal tract. FA was abnormally lower in girls with FXS in the posterior limbs of the internal capsule, posterior thalami, and precentral gyrus. Girls with TS had lower FA in the inferior longitudinal fasciculus, right internal capsule and left cerebellar peduncle. Partially overlapping neurodevelopmental anomalies were detected in all three neurogenetic disorders. Altered white matter integrity in the superior and inferior longitudinal fasciculi and thalamic to frontal tracts may contribute to the behavioral characteristics of all of these disorders. PMID:23602925

  9. [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.

  10. 32 CFR 516.20 - Habeas Corpus.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... Attorney's Office immediately upon learning that a petition for writ of habeas corpus has been filed. All... guidance from Litigation Division. (e) Foreign court orders. A foreign court should not inquire into...

  11. 32 CFR 516.20 - Habeas Corpus.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... Attorney's Office immediately upon learning that a petition for writ of habeas corpus has been filed. All... guidance from Litigation Division. (e) Foreign court orders. A foreign court should not inquire into...

  12. [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

  13. Diffuse white matter tract abnormalities in clinically normal ageing retired athletes with a history of sports-related concussions.

    PubMed

    Tremblay, Sebastien; Henry, Luke C; Bedetti, Christophe; Larson-Dupuis, Camille; Gagnon, Jean-François; Evans, Alan C; Théoret, Hugo; Lassonde, Maryse; De Beaumont, Louis

    2014-11-01

    Sports-related concussions have been shown to lead to persistent subclinical anomalies of the motor and cognitive systems in young asymptomatic athletes. In advancing age, these latent alterations correlate with detectable motor and cognitive function decline. Until now, the interacting effects of concussions and the normal ageing process on white matter tract integrity remain unknown. Here we used a tract-based spatial statistical method to uncover potential white matter tissue damage in 15 retired athletes with a history of concussions, free of comorbid medical conditions. We also investigated potential associations between white matter integrity and declines in cognitive and motor functions. Compared to an age- and education-matched control group of 15 retired athletes without concussions, former athletes with concussions exhibited widespread white matter anomalies along many major association, interhemispheric, and projection tracts. Group contrasts revealed decreases in fractional anisotropy, as well as increases in mean and radial diffusivity measures in the concussed group. These differences were primarily apparent in fronto-parietal networks as well as in the frontal aspect of the corpus callosum. The white matter anomalies uncovered in concussed athletes were significantly associated with a decline in episodic memory and lateral ventricle expansion. Finally, the expected association between frontal white matter integrity and motor learning found in former non-concussed athletes was absent in concussed participants. Together, these results show that advancing age in retired athletes presenting with a history of sports-related concussions is linked to diffuse white matter abnormalities that are consistent with the effects of traumatic axonal injury and exacerbated demyelination. These changes in white matter integrity might explain the cognitive and motor function declines documented in this population.

  14. Diffuse white matter tract abnormalities in clinically normal ageing retired athletes with a history of sports-related concussions

    PubMed Central

    Tremblay, Sebastien; Henry, Luke C.; Bedetti, Christophe; Larson-Dupuis, Camille; Gagnon, Jean-François; Evans, Alan C.; Théoret, Hugo; Lassonde, Maryse

    2014-01-01

    Sports-related concussions have been shown to lead to persistent subclinical anomalies of the motor and cognitive systems in young asymptomatic athletes. In advancing age, these latent alterations correlate with detectable motor and cognitive function decline. Until now, the interacting effects of concussions and the normal ageing process on white matter tract integrity remain unknown. Here we used a tract-based spatial statistical method to uncover potential white matter tissue damage in 15 retired athletes with a history of concussions, free of comorbid medical conditions. We also investigated potential associations between white matter integrity and declines in cognitive and motor functions. Compared to an age- and education-matched control group of 15 retired athletes without concussions, former athletes with concussions exhibited widespread white matter anomalies along many major association, interhemispheric, and projection tracts. Group contrasts revealed decreases in fractional anisotropy, as well as increases in mean and radial diffusivity measures in the concussed group. These differences were primarily apparent in fronto-parietal networks as well as in the frontal aspect of the corpus callosum. The white matter anomalies uncovered in concussed athletes were significantly associated with a decline in episodic memory and lateral ventricle expansion. Finally, the expected association between frontal white matter integrity and motor learning found in former non-concussed athletes was absent in concussed participants. Together, these results show that advancing age in retired athletes presenting with a history of sports-related concussions is linked to diffuse white matter abnormalities that are consistent with the effects of traumatic axonal injury and exacerbated demyelination. These changes in white matter integrity might explain the cognitive and motor function declines documented in this population. PMID:25186429

  15. 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

  16. 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…

  17. [The endothelium of the corpus cavernosum].

    PubMed

    Bennani, S; Benjelloun, S

    1994-01-01

    Recently, it has been demonstrated that the endothelium of corpus cavernosum plays an important role in the physiology of erection. Endothelial cells synthesize and release constricting and relaxing factors. These factors are essentially represented by endothelin and nitric oxide. Endothelin is a peptide generated by endothelial cells with potent vasoconstrictor properties. This peptide provokes more sustained constriction of corpus cavernosum smooth muscles than noradrenaline. This effect suggested that endothelin may play a role in the regulation of tone in penile vascular and cavernous tissues in man. In addition, recent experimental studies showed an important role of nitric oxide for cavernous smooth muscle relaxation. This factor may act as an inhibitory neurotransmitter in penile corpus cavernosum smooth muscle. The characteristics of these substances are reviewed. PMID:7822706

  18. Bayesian stratified sampling to assess corpus utility

    SciTech Connect

    Hochberg, J.; Scovel, C.; Thomas, T.; Hall, S.

    1998-12-01

    This paper describes a method for asking statistical questions about a large text corpus. The authors exemplify the method by addressing the question, ``What percentage of Federal Register documents are real documents, of possible interest to a text researcher or analyst?`` They estimate an answer to this question by evaluating 200 documents selected from a corpus of 45,820 Federal Register documents. Bayesian analysis and stratified sampling are used to reduce the sampling uncertainty of the estimate from over 3,100 documents to fewer than 1,000. A possible application of the method is to establish baseline statistics used to estimate recall rates for information retrieval systems.

  19. Phenotype and management of Aicardi syndrome: new findings from a survey of 69 children

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aicardi syndrome is a rare neurodevelopmental disorder characterized by agenesis of the corpus callosum, other developmental brain abnormalities, chorioretinal lacunae, and severe seizures. Current clinical knowledge is derived from small series that focus on these major defects. The authors perform...

  20. Neuronal Migration Disorders

    MedlinePlus

    ... of the corpus callosum, and agenesis of the cranial nerves. Symptoms vary according to the abnormality, but often feature poor muscle tone and motor function, seizures, developmental delays, ... facial or skull features that can be recognized by a neurologist. ...

  1. Intracerebroventricular injection of propionic acid, an enteric metabolite implicated in autism, induces social abnormalities that do not differ between seizure-prone (FAST) and seizure-resistant (SLOW) rats.

    PubMed

    Shultz, Sandy R; Aziz, Noor A B; Yang, Li; Sun, Mujun; MacFabe, Derrick F; O'Brien, Terence J

    2015-02-01

    Autism is a complex neurodevelopmental disorder that is characterized by social abnormalities. Genetic, dietary and gut-related factors are implicated in autism, however the causal properties of these factors and how they may interact are unclear. Propionic acid (PPA) is a product of gut microbiota and a food preservative. PPA has been linked to autism, and PPA administration to rats is an animal model of the condition. Seizure-prone (FAST) and seizure-resistant (SLOW) rats were initially developed to investigate differential vulnerability to developing epilepsy. However, FAST rats also display autistic-like features, and have been proposed as a genetic model of autism. Here we examined the effects of PPA on social behavior in FAST and SLOW rats. A single intracerebroventricular injection of PPA, or phosphate-buffered saline (PBS), was administered to young-adult male FAST and SLOW rats. Immediately after treatment, rats were placed in same-treatment and same-strain pairs, and underwent social behavior testing. PPA induced social abnormalities in both FAST and SLOW rat strains. While there was no evidence of social impairment in FAST rats that were not treated with PPA, these rats were hyperactive relative to SLOW rats. Post-mortem immunofluorescence analysis of brain tissue indicated that PPA treatment resulted in increased astrogliosis in the corpus callosum and cortex compared to PBS treatment. FAST rats had increased astrogliosis in the cortex compared to SLOW rats. Together these findings support the use of PPA as a rat model of autism, but indicate there are no interactive effects between the PPA and FAST models.

  2. 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…

  3. 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…

  4. Integrating Corpus Consultation in Language Studies

    ERIC Educational Resources Information Center

    Chambers, Angela

    2005-01-01

    Alongside developments in language research, the potential of corpora as a resource in language learning and teaching has been evident to researchers and teachers since the late 1960s. Despite publications which emphasise the benefits of corpus consultation for language learners (Bernardini, 2002; Kennedy & Miceli, 2001), there is little evidence…

  5. 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…

  6. 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…

  7. 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;…

  8. 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

  9. Executive deficits, not processing speed relates to abnormalities in distinct prefrontal tracts in amyotrophic lateral sclerosis.

    PubMed

    Pettit, Lewis D; Bastin, Mark E; Smith, Colin; Bak, Thomas H; Gillingwater, Thomas H; Abrahams, Sharon

    2013-11-01

    , uncinate fasciculus and hippocampal portion of the cingulum bundles. Significant differences also emerged in the anterior corona radiata as well as in white matter underlying the superior, medial and inferior frontal gyri and the temporal gyri. Dual-task performance significantly correlated with fractional anisotropy measures in the middle frontal gyrus white matter and anterior corona radiata. Letter fluency indices significantly correlated with fractional anisotropy measures of the inferior frontal gyrus white matter and corpus callosum in addition to the corticospinal tracts and mean diffusivity measures in the white matter of the superior frontal gyrus. The current study demonstrates that cognitive impairment in amyotrophic lateral sclerosis is not due to generic slowing of processing speed. Moreover, different executive deficits are related to distinct prefrontal tract involvement in amyotrophic lateral sclerosis with dual-task impairment associating with dorsolateral prefrontal dysfunction and letter fluency showing greater dependence on inferolateral prefrontal dysfunction.

  10. 76 FR 18395 - Safety Zone; Naval Air Station Corpus Christi Air Show, Oso Bay, Corpus Christi, TX

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-04

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Naval Air Station Corpus Christi Air Show..., Texas in support of the 2011 Naval Air Station Corpus Christi Air Show. This temporary safety zone is... necessary to ensure the safety of participants and spectators in the Naval Air Station Corpus Christi...

  11. 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

  12. Mesonephric adenocarcinoma of the uterine corpus

    PubMed Central

    Wu, Haixia; Zhang, Lin; Cao, Wenfeng; Hu, Yuanjing; Liu, Yixin

    2014-01-01

    Mesonephric carcinomas are rare in the female genital tract and usually are found in sites where embryonic remnants of wolffian ducts are usually detected, such as the uterine cervix, broad ligament, mesosalpinx and exceptionally rarely in the uterine corpus. To date, only four cases of mesonephric carcinomas arising in the uterine corpus have been described in literature. Here we report two cases of mesonephric carcinomas arising in a deep intramural location of the uterine corpus in a 55-year-old woman and a 62-year-old woman in Chinese populations. It is believed to be the first report in China. Both cases presented with a little postmenopausal bleeding. Before hospitalized, uterine curettages were programmed for both cases. The pathology reports were mesonephric adenocarcinoma. A total hysterectomy and bilateral salpingo-oophorectomy were performed. On gross examination, the tumors of both cases were confined to the myometrium. Microscopic examination found both tumors of these two cases were adenocarcinomas mixed with spindle cell component. The most primary histologic patterns of the mesonephric adenocarcinomas were tubular glands that varied in size and were lined by one to several layers of columnar cells. Immunohistochemically, the tumor cells expressed positive with CD10, calretinin, vimentin, cytokeratin (AE1/AE3) and epithelial membrane antigen (EMA); but expressions of ER and PR were completely negative. The peculiar location of mesonephric carcinoma of the uterine corpus may be misinterpreted as other histological type neoplasms. Awareness of this rare phenomenon and immunostaining for markers of mesonephric carcinoma can prevent from making a false diagnosis. PMID:25400789

  13. 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.

  14. Bilateral redundancy gain and callosal integrity in a man with callosal lipoma: a diffusion-tensor imaging study.

    PubMed

    Roser, Matthew E; Corballis, Michael C; Jansari, Ashok; Fulford, Jon; Benattayallah, Abdelmalek; Adams, William M

    2012-06-01

    We investigated whether abnormalities in the structural organization of the corpus callosum in the presence of curvilinear lipoma are associated with increased facilitation of response time to bilateral stimuli, an effect known as the redundancy gain (RG). A patient (A.J.) with a curvilinear lipoma of the corpus callosum, his genetically-identical twin, and age-matched control participants made speeded responses to luminant stimuli. Structural organization of callosal regions was assessed with diffusion-tensor imaging. A.J. was found to have reduced structural integrity in the splenium of the corpus callosum and produced a large RG suggestive of neural summation. PMID:21787244

  15. 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

  16. 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

  17. 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

  18. Corpus-Assisted Creative Writing: Introducing Intermediate Italian Learners to a Corpus as a Reference Resource

    ERIC Educational Resources Information Center

    Kennedy, Claire; Miceli, Tiziana

    2010-01-01

    In much of the literature on the exploitation of corpora for language learning, the learners are viewed as researchers, who formulate and test their own hypotheses about language use. Having identified difficulties encountered in corpus investigations by our intermediate-level students of Italian in a previous study, we have designed a…

  19. 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

  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. Mapping abnormal subcortical brain morphometry in an elderly HIV+ cohort.

    PubMed

    Wade, Benjamin S C; Valcour, Victor G; Wendelken-Riegelhaupt, Lauren; Esmaeili-Firidouni, Pardis; Joshi, Shantanu H; Gutman, Boris A; Thompson, Paul M

    2015-01-01

    Over 50% of HIV + individuals exhibit neurocognitive impairment and subcortical atrophy, but the profile of brain abnormalities associated with HIV is still poorly understood. Using surface-based shape analyses, we mapped the 3D profile of subcortical morphometry in 63 elderly HIV + participants and 31 uninfected controls. The thalamus, caudate, putamen, pallidum, hippocampus, amygdala, brainstem, accumbens, callosum and ventricles were segmented from high-resolution MRIs. To investigate shape-based morphometry, we analyzed the Jacobian determinant (JD) and radial distances (RD) defined on each region's surfaces. We also investigated effects of nadir CD4 + T-cell counts, viral load, time since diagnosis (TSD) and cognition on subcortical morphology. Lastly, we explored whether HIV + participants were distinguishable from unaffected controls in a machine learning context. All shape and volume features were included in a random forest (RF) model. The model was validated with 2-fold cross-validation. Volumes of HIV + participants' bilateral thalamus, left pallidum, left putamen and callosum were significantly reduced while ventricular spaces were enlarged. Significant shape variation was associated with HIV status, TSD and the Wechsler adult intelligence scale. HIV + people had diffuse atrophy, particularly in the caudate, putamen, hippocampus and thalamus. Unexpectedly, extended TSD was associated with increased thickness of the anterior right pallidum. In the classification of HIV + participants vs. controls, our RF model attained an area under the curve of 72%.

  2. Mapping abnormal subcortical brain morphometry in an elderly HIV + cohort

    PubMed Central

    Wade, Benjamin S.C.; Valcour, Victor G.; Wendelken-Riegelhaupt, Lauren; Esmaeili-Firidouni, Pardis; Joshi, Shantanu H.; Gutman, Boris A.; Thompson, Paul M.

    2015-01-01

    Over 50% of HIV + individuals exhibit neurocognitive impairment and subcortical atrophy, but the profile of brain abnormalities associated with HIV is still poorly understood. Using surface-based shape analyses, we mapped the 3D profile of subcortical morphometry in 63 elderly HIV + participants and 31 uninfected controls. The thalamus, caudate, putamen, pallidum, hippocampus, amygdala, brainstem, accumbens, callosum and ventricles were segmented from high-resolution MRIs. To investigate shape-based morphometry, we analyzed the Jacobian determinant (JD) and radial distances (RD) defined on each region's surfaces. We also investigated effects of nadir CD4 + T-cell counts, viral load, time since diagnosis (TSD) and cognition on subcortical morphology. Lastly, we explored whether HIV + participants were distinguishable from unaffected controls in a machine learning context. All shape and volume features were included in a random forest (RF) model. The model was validated with 2-fold cross-validation. Volumes of HIV + participants' bilateral thalamus, left pallidum, left putamen and callosum were significantly reduced while ventricular spaces were enlarged. Significant shape variation was associated with HIV status, TSD and the Wechsler adult intelligence scale. HIV + people had diffuse atrophy, particularly in the caudate, putamen, hippocampus and thalamus. Unexpectedly, extended TSD was associated with increased thickness of the anterior right pallidum. In the classification of HIV + participants vs. controls, our RF model attained an area under the curve of 72%. PMID:26640768

  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. Designing a Corpus for Translation and Language Teaching.

    ERIC Educational Resources Information Center

    Bernardini, Silvia

    2003-01-01

    Describes a million-word corpus for English-Italian translation students. Outlines the design, which makes multiple types of comparisons possible among originals and translations and illustrates how to use the corpus to teach sociocultural insights, discourse-structuring expressions, and lexical patterns. (Author/VWL)

  5. 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,…

  6. 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…

  7. 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…

  8. Codeswitching, Borrowing and Mixing in a Corpus of Xhosa English

    ERIC Educational Resources Information Center

    de Klerk, Vivian

    2006-01-01

    The paper analyses selected aspects of the codeswitching behaviour in a spoken corpus of the English of 326 people, all of them mother-tongue speakers of Xhosa (a local African language in South Africa), and all of whom would see themselves as Xhosa/English bilinguals. The corpus comprises approximately 550,000 transcribed words of spontaneous,…

  9. 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)…

  10. 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...

  11. Corpus-Based Word Sense Disambiguation

    NASA Astrophysics Data System (ADS)

    Fujii, Atsushi

    1998-04-01

    Resolution of lexical ambiguity, commonly termed ``word sense disambiguation'', is expected to improve the analytical accuracy for tasks which are sensitive to lexical semantics. Such tasks include machine translation, information retrieval, parsing, natural language understanding and lexicography. Reflecting the growth in utilization of machine readable texts, word sense disambiguation techniques have been explored variously in the context of corpus-based approaches. Within one corpus-based framework, that is the similarity-based method, systems use a database, in which example sentences are manually annotated with correct word senses. Given an input, systems search the database for the most similar example to the input. The lexical ambiguity of a word contained in the input is resolved by selecting the sense annotation of the retrieved example. In this research, we apply this method of resolution of verbal polysemy, in which the similarity between two examples is computed as the weighted average of the similarity between complements governed by a target polysemous verb. We explore similarity-based verb sense disambiguation focusing on the following three methods. First, we propose a weighting schema for each verb complement in the similarity computation. Second, in similarity-based techniques, the overhead for manual supervision and searching the large-sized database can be prohibitive. To resolve this problem, we propose a method to select a small number of effective examples, for system usage. Finally, the efficiency of our system is highly dependent on the similarity computation used. To maximize efficiency, we propose a method which integrates the advantages of previous methods for similarity computation.

  12. 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

  13. 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

  14. A corpus of noise-induced word misperceptions for Spanish.

    PubMed

    Tóth, Máté Attila; García Lecumberri, María Luisa; Tang, Yan; Cooke, Martin

    2015-02-01

    Word misperceptions are valuable in designing and evaluating detailed computational models of speech perception, especially when a number of listeners agree on the misperceived word. The current paper describes the elicitation of a corpus of Spanish word misperceptions induced by different types of noise. Stimuli were presented using an adaptive procedure designed to promote the rapid discovery of misperceptions. The final corpus contains 3235 misperceptions along with speech and masker waveforms, permitting further experimental and modeling studies into the origin of each misperception. The corpus is available online as an open resource.

  15. Sexual dimorphic abnormalities in white matter geometry common to schizophrenia and non-psychotic high-risk subjects: Evidence for a neurodevelopmental risk marker?

    PubMed

    Savadjiev, Peter; Seidman, Larry J; Thermenos, Heidi; Keshavan, Matcheri; Whitfield-Gabrieli, Susan; Crow, Tim J; Kubicki, Marek

    2016-01-01

    The characterization of neurodevelopmental aspects of brain alterations require neuroimaging methods that reflect correlates of neurodevelopment, while being robust to other progressive pathological processes. Newly developed neuroimaging methods for measuring geometrical features of the white matter fall exactly into this category. Our recent work shows that such features, measured in the anterior corpus callosum in diffusion MRI data, correlate with psychosis symptoms in patients with adolescent onset schizophrenia and subside a reversal of normal sexual dimorphism. Here, we test the hypothesis that similar developmental deviations will also be present in nonpsychotic subjects at familial high risk (FHR) for schizophrenia, due to genetic predispositions. Demonstrating such changes would provide a strong indication of neurodevelopmental deviation extant before, and independent of pathological changes occurring after disease onset. We examined the macrostructural geometry of corpus callosum white matter in diffusion MRI data of 35 non-psychotic subjects with genetic (familial) risk for schizophrenia, and 26 control subjects, both male and female. We report a reversal of normal sexual dimorphism in callosal white matter geometry consistent with recent results in adolescent onset schizophrenia. This pattern may be indicative of an error in neurogenesis and a possible trait marker of schizophrenia.

  16. Tooth - abnormal shape

    MedlinePlus

    Hutchinson incisors; Abnormal tooth shape; Peg teeth; Mulberry teeth; Conical teeth ... The appearance of normal teeth varies, especially the molars. ... conditions. Specific diseases can affect tooth shape, tooth ...

  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. Structurally abnormal human autosomes

    SciTech Connect

    1993-12-31

    Chapter 25, discusses structurally abnormal human autosomes. This discussion includes: structurally abnormal chromosomes, chromosomal polymorphisms, pericentric inversions, paracentric inversions, deletions or partial monosomies, cri du chat (cat cry) syndrome, ring chromosomes, insertions, duplication or pure partial trisomy and mosaicism. 71 refs., 8 figs.

  20. 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.

  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. Morphological abnormalities among lampreys

    USGS Publications Warehouse

    Manion, Patrick J.

    1967-01-01

    The experimental control of the sea lamprey (Petromyzon marinus) in the Great Lakes has required the collection of thousands of lampreys. Representatives of each life stage of the four species of the Lake Superior basin were examined for structural abnormalities. The most common aberration was the presence of additional tails. The accessory tails were always postanal and smaller than the normal tail. The point of origin varied; the extra tails occurred on dorsal, ventral, or lateral surfaces. Some of the extra tails were misshaped and curled, but others were normal in shape and pigment pattern. Other abnormalities in larval sea lampreys were malformed or twisted tails and bodies. The cause of the structural abnormalities is unknown. The presence of extra caudal fins could be genetically controlled, or be due to partial amputation or injury followed by abnormal regeneration. Few if any lampreys with structural abnormalities live to sexual maturity.

  3. Contrast radiographic study of venous drainage of the corpus cavernosum and the corpus spongiosum of the cat penis.

    PubMed

    Amiri, Ali Akbar; Gilanpour, Hassan; Veshkini, Abbas

    2014-01-01

    The aim of this study was to determine the drainage routes of the corpus cvernosum penis and the corpus spongiosum penis in the cat using contrast cavernosography. Five male cats, 1.5-2.5 years old, weighing between 4.5 and 5.5 kg were investigated. The cats were anesthetized and the root and the proximal part of the penis were exposed by an incision on the perineum reaching the scrotum. Each cat was radiographed in lateral and dorsal recumbency before and during injection of contrast medium into the erectile bodies. The corpus spongiosum penis was injected at the bulb of the penis and the corpus cavernosum penis at the root. Injection of contrast media into the cavernous bodies showed that both the external and internal iliac veins drain the erectile bodies into the caudal vena cava. Drainage from the corpus spongiosum penis was from the bulb for the proximal part and from the glans for the distal part. The corpus cavernosum penis was drained only proximally, from the crura. There was a network of veins above the pelvic symphysis and the drainage of erectile bodies where through various routes into the internal and external iliac veins.

  4. Abnormal uterine bleeding.

    PubMed

    Jennings, J C

    1995-11-01

    Physicians who care for female patients cannot avoid the frequent complaint of abnormal uterine bleeding. Knowledge of the disorders that cause this problem can prevent serious consequences in many patients and improve the quality of life for many others. The availability of noninvasive and minimally invasive diagnostic studies and minimally invasive surgical treatment has revolutionized management of abnormal uterine bleeding. Similar to any other disorder, the extent to which a physician manages abnormal uterine bleeding depends on his or her own level of comfort. When limitations of either diagnostic or therapeutic capability are encountered, consultation and referral should be used to the best interest of patients.

  5. "Jeopardy" in Abnormal Psychology.

    ERIC Educational Resources Information Center

    Keutzer, Carolin S.

    1993-01-01

    Describes the use of the board game, Jeopardy, in a college level abnormal psychology course. Finds increased student interaction and improved application of information. Reports generally favorable student evaluation of the technique. (CFR)

  6. Abnormal Uterine Bleeding

    MedlinePlus

    ... Abnormal uterine bleeding is any bleeding from the uterus (through your vagina) other than your normal monthly ... or fibroids (small and large growths) in the uterus can also cause bleeding. Rarely, a thyroid problem, ...

  7. Abnormal Uterine Bleeding FAQ

    MedlinePlus

    ... as cancer of the uterus, cervix, or vagina • Polycystic ovary syndrome How is abnormal bleeding diagnosed? Your health care ... before the fetus can survive outside the uterus. Polycystic Ovary Syndrome: A condition characterized by two of the following ...

  8. Corpus luteum hemorrhage in women with bleeding disorders.

    PubMed

    Hoffman, Ron; Brenner, Benjamin

    2009-01-01

    Bleeding into the corpus luteum following ovulation rarely has clinical significance in healthy women, but may lead to life-threatening hemorrhage in women with congenital or acquired bleeding disorders. Women who are at an increased risk for corpus luteum hemorrhage (CLH) can be divided in two categories; first, those taking anticoagulants because of a thrombotic disorder; and second, women with congenital bleeding disorders. The management and prevention of CLH is still unsettled and the literature dealing with this problem is based on case reports only. This review focuses on the pathophysiology, clinical presentation, diagnosis and treatment options of an acute bleeding event and prevention modalities of CLH in women with bleeding disorders.

  9. 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.

  10. Corpus-based identification and refinement of semantic classes.

    PubMed Central

    Nazarenko, A.; Zweigenbaum, P.; Bouaud, J.; Habert, B.

    1997-01-01

    Medical Language Processing (MLP), especially in specific domains, requires fine-grained semantic lexica. We examine whether robust natural language processing tools used on a representative corpus of a domain help in building and refining a semantic categorization. We test this hypothesis with ZELLIG, a corpus analysis tool. The first clusters we obtain are consistent with a model of the domain, as found in the SNOMED nomenclature. They correspond to coarse-grained semantic categories, but isolate as well lexical idiosyncrasies belonging to the clinical sub-language. Moreover, they help categorize additional words. PMID:9357693

  11. [Hair shaft abnormalities].

    PubMed

    Itin, P H; Düggelin, M

    2002-05-01

    Hair shaft disorders may lead to brittleness and uncombable hair. In general the hair feels dry and lusterless. Hair shaft abnormalities may occur as localized or generalized disorders. Genetic predisposition or exogenous factors are able to produce and maintain hair shaft abnormalities. In addition to an extensive history and physical examination the most important diagnostic examination to analyze a hair shaft problem is light microscopy. Therapy of hair shaft disorders should focus to the cause. In addition, minimizing traumatic influences to hair shafts, such as dry hair with an electric dryer, permanent waves and dyes is important. A short hair style is more suitable for such patients with hair shaft disorders.

  12. 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…

  13. 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…

  14. 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…

  15. 38 CFR 3.263 - Corpus of estate; net worth.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... amounts received as compensation under the Victims of Crime Act of 1984 unless the total amount of... losses suffered as a result of the crime. (Authority: 42 U.S.C. 10602(c)) (i) Medicare Prescription Drug... the corpus of estate of a parent where dependency is a factor under § 3.250, and the net worth of...

  16. 38 CFR 3.263 - Corpus of estate; net worth.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... amounts received as compensation under the Victims of Crime Act of 1984 unless the total amount of... losses suffered as a result of the crime. (Authority: 42 U.S.C. 10602(c)) (i) Medicare Prescription Drug... the corpus of estate of a parent where dependency is a factor under § 3.250, and the net worth of...

  17. 38 CFR 3.263 - Corpus of estate; net worth.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... amounts received as compensation under the Victims of Crime Act of 1984 unless the total amount of... losses suffered as a result of the crime. (Authority: 42 U.S.C. 10602(c)) (i) Medicare Prescription Drug... the corpus of estate of a parent where dependency is a factor under § 3.250, and the net worth of...

  18. 38 CFR 3.263 - Corpus of estate; net worth.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... amounts received as compensation under the Victims of Crime Act of 1984 unless the total amount of... losses suffered as a result of the crime. (Authority: 42 U.S.C. 10602(c)) (i) Medicare Prescription Drug... the corpus of estate of a parent where dependency is a factor under § 3.250, and the net worth of...

  19. 38 CFR 3.263 - Corpus of estate; net worth.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... amounts received as compensation under the Victims of Crime Act of 1984 unless the total amount of... losses suffered as a result of the crime. (Authority: 42 U.S.C. 10602(c)) (i) Medicare Prescription Drug... the corpus of estate of a parent where dependency is a factor under § 3.250, and the net worth of...

  20. 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…

  1. 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…

  2. 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…

  3. You Should Have the Body: Understanding Habeas Corpus

    ERIC Educational Resources Information Center

    Landman, James

    2008-01-01

    English legal commentator William Blackstone described the writ of habeas corpus as a second Magna Carta, and Supreme Court Chief Justice John Marshall called it the "great writ." It has been part of the Anglo-American common law tradition since the Middle Ages. In the United States, it has been a source of tension between state and federal…

  4. 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…

  5. 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

  6. 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…

  7. 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…

  8. 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…

  9. Integrating Corpus Work into Secondary Education: From Data-Driven Learning to Needs-Driven Corpora

    ERIC Educational Resources Information Center

    Braun, Sabine

    2007-01-01

    This paper reports on an empirical case study conducted to investigate the overall conditions and challenges of integrating corpus materials and corpus-based learning activities into English-language classes at a secondary school in Germany. Starting from the observation that in spite of the large amount of research into corpus-based language…

  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. The role of GPR1 signaling in mice corpus luteum

    PubMed Central

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

    2016-01-01

    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

  12. Unsupervised detection of abnormalities in medical images using salient features

    NASA Astrophysics Data System (ADS)

    Alpert, Sharon; Kisilev, Pavel

    2014-03-01

    In this paper we propose a new method for abnormality detection in medical images which is based on the notion of medical saliency. The proposed method is general and is suitable for a variety of tasks related to detection of: 1) lesions and microcalcifications (MCC) in mammographic images, 2) stenoses in angiographic images, 3) lesions found in magnetic resonance (MRI) images of brain. The main idea of our approach is that abnormalities manifest as rare events, that is, as salient areas compared to normal tissues. We define the notion of medical saliency by combining local patch information from the lightness channel with geometric shape local descriptors. We demonstrate the efficacy of the proposed method by applying it to various modalities, and to various abnormality detection problems. Promising results are demonstrated for detection of MCC and of masses in mammographic images, detection of stenoses in angiography images, and detection of lesions in brain MRI. We also demonstrate how the proposed automatic abnormality detection method can be combined with a system that performs supervised classification of mammogram images into benign or malignant/premalignant MCC's. We use a well known DDSM mammogram database for the experiment on MCC classification, and obtain 80% accuracy in classifying images containing premalignant MCC versus benign ones. In contrast to supervised detection methods, the proposed approach does not rely on ground truth markings, and, as such, is very attractive and applicable for big corpus image data processing.

  13. 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…

  14. 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…

  15. Towards a Computable Data Corpus of Temporal Correlations between Drug Administration and Lab Value Changes

    PubMed Central

    Newe, Axel; Wimmer, Stefan; Neubert, Antje; Becker, Linda; Prokosch, Hans-Ulrich; Ganslandt, Thomas

    2015-01-01

    Background The analysis of electronic health records for an automated detection of adverse drug reactions is an approach to solve the problems that arise from traditional methods like spontaneous reporting or manual chart review. Algorithms addressing this task should be modeled on the criteria for a standardized case causality assessment defined by the World Health Organization. One of these criteria is the temporal relationship between drug intake and the occurrence of a reaction or a laboratory test abnormality. Appropriate data that would allow for developing or validating related algorithms is not publicly available, though. Methods In order to provide such data, retrospective routine data of drug administrations and temporally corresponding laboratory observations from a university clinic were extracted, transformed and evaluated by experts in terms of a reasonable time relationship between drug administration and lab value alteration. Result The result is a data corpus of 400 episodes of normalized laboratory parameter values in temporal context with drug administrations. Each episode has been manually classified whether it contains data that might indicate a temporal correlation between the drug administration and the change of the lab value course, whether such a change is not observable or whether a decision between those two options is not possible due to the data. In addition, each episode has been assigned a concordance value which indicates how difficult it is to assess. This is the first open data corpus of a computable ground truth of temporal correlations between drug administration and lab value alterations. Discussion The main purpose of this data corpus is the provision of data for further research and the provision of a ground truth which allows for comparing the outcome of other assessments of this data with the outcome of assessments made by human experts. It can serve as a contribution towards systematic, computerized ADR detection in

  16. Morphological abnormalities in elasmobranchs.

    PubMed

    Moore, A B M

    2015-08-01

    A total of 10 abnormal free-swimming (i.e., post-birth) elasmobranchs are reported from The (Persian-Arabian) Gulf, encompassing five species and including deformed heads, snouts, caudal fins and claspers. The complete absence of pelvic fins in a milk shark Rhizoprionodon acutus may be the first record in any elasmobranch. Possible causes, including the extreme environmental conditions and the high level of anthropogenic pollution particular to The Gulf, are briefly discussed.

  17. Chromosome abnormalities in glioma

    SciTech Connect

    Li, Y.S.; Ramsay, D.A.; Fan, Y.S.

    1994-09-01

    Cytogenetic studies were performed in 25 patients with gliomas. An interesting finding was a seemingly identical abnormality, an extra band on the tip of the short arm of chromosome 1, add(1)(p36), in two cases. The abnormality was present in all cells from a patient with a glioblastoma and in 27% of the tumor cells from a patient with a recurrent irradiated anaplastic astrocytoma; in the latter case, 7 unrelated abnormal clones were identified except 4 of those clones shared a common change, -Y. Three similar cases have been described previously. In a patient with pleomorphic astrocytoma, the band 1q42 in both homologues of chromosome 1 was involved in two different rearrangements. A review of the literature revealed that deletion of the long arm of chromosome 1 including 1q42 often occurs in glioma. This may indicate a possible tumor suppressor gene in this region. Cytogenetic follow-up studies were carried out in two patients and emergence of unrelated clones were noted in both. A total of 124 clonal breakpoints were identified in the 25 patients. The breakpoints which occurred three times or more were: 1p36, 1p22, 1q21, 1q25, 3q21, 7q32, 8q22, 9q22, 16q22, and 22q13.

  18. [Congenital foot abnormalities].

    PubMed

    Delpont, M; Lafosse, T; Bachy, M; Mary, P; Alves, A; Vialle, R

    2015-03-01

    The foot may be the site of birth defects. These abnormalities are sometimes suspected prenatally. Final diagnosis depends on clinical examination at birth. These deformations can be simple malpositions: metatarsus adductus, talipes calcaneovalgus and pes supinatus. The prognosis is excellent spontaneously or with a simple orthopedic treatment. Surgery remains outstanding. The use of a pediatric orthopedist will be considered if malposition does not relax after several weeks. Malformations (clubfoot, vertical talus and skew foot) require specialized care early. Clubfoot is characterized by an equine and varus hindfoot, an adducted and supine forefoot, not reducible. Vertical talus combines equine hindfoot and dorsiflexion of the forefoot, which is performed in the midfoot instead of the ankle. Skew foot is suspected when a metatarsus adductus is resistant to conservative treatment. Early treatment is primarily orthopedic at birth. Surgical treatment begins to be considered after walking age. Keep in mind that an abnormality of the foot may be associated with other conditions: malposition with congenital hip, malformations with syndromes, neurological and genetic abnormalities. PMID:25524290

  19. Abnormal pressures as hydrodynamic phenomena

    USGS Publications Warehouse

    Neuzil, C.E.

    1995-01-01

    So-called abnormal pressures, subsurface fluid pressures significantly higher or lower than hydrostatic, have excited speculation about their origin since subsurface exploration first encountered them. Two distinct conceptual models for abnormal pressures have gained currency among earth scientists. The static model sees abnormal pressures generally as relict features preserved by a virtual absence of fluid flow over geologic time. The hydrodynamic model instead envisions abnormal pressures as phenomena in which flow usually plays an important role. This paper develops the theoretical framework for abnormal pressures as hydrodynamic phenomena, shows that it explains the manifold occurrences of abnormal pressures, and examines the implications of this approach. -from Author

  20. Feeling Abnormal: Simulation of Deviancy in Abnormal and Exceptionality Courses.

    ERIC Educational Resources Information Center

    Fernald, Charles D.

    1980-01-01

    Describes activity in which student in abnormal psychology and psychology of exceptional children classes personally experience being judged abnormal. The experience allows the students to remember relevant research, become sensitized to the feelings of individuals classified as deviant, and use caution in classifying individuals as abnormal.…

  1. Abnormal human sex chromosome constitutions

    SciTech Connect

    1993-12-31

    Chapter 22, discusses abnormal human sex chromosome constitution. Aneuploidy of X chromosomes with a female phenotype, sex chromosome aneuploidy with a male phenotype, and various abnormalities in X chromosome behavior are described. 31 refs., 2 figs.

  2. Exercises to Improve Gait Abnormalities

    MedlinePlus

    ... Home About iChip Articles Directories Videos Resources Contact Exercises to Improve Gait Abnormalities Home » Article Categories » Exercise and Fitness Font Size: A A A A Exercises to Improve Gait Abnormalities Next Page The manner ...

  3. 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

  4. Implicit causality bias in English: a corpus of 300 verbs.

    PubMed

    Ferstl, Evelyn C; Garnham, Alan; Manouilidou, Christina

    2011-03-01

    This study provides implicit verb causality norms for a corpus of 305 English verbs. A web-based sentence completion study was conducted, with 96 respondents completing fragments such as "John liked Mary because..." The resulting bias scores are provided as supplementary material in the Psychonomic Society Archive, where we also present lexical and semantic verb features, such as the frequency, semantic class and emotional valence. Our results replicate those of previous studies with much smaller numbers of verbs and respondents. Novel effects of gender and its interaction with verb valence illustrate the type of issues that can be investigated using stable norms for a large number of verbs. The corpus will facilitate future studies in a range of areas, including psycholinguistics and social psychology.

  5. Abnormal ionization in sonoluminescence

    NASA Astrophysics Data System (ADS)

    Zhang, Wen-Juan; An, Yu

    2015-04-01

    Sonoluminescence is a complex phenomenon, the mechanism of which remains unclear. The present study reveals that an abnormal ionization process is likely to be present in the sonoluminescing bubble. To fit the experimental data of previous studies, we assume that the ionization energies of the molecules and atoms in the bubble decrease as the gas density increases and that the decrease of the ionization energy reaches about 60%-70% as the bubble flashes, which is difficult to explain by using previous models. Project supported by the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20120002110031) and the National Natural Science Foundation of China (Grant No. 11334005).

  6. [Wine and women: an overlooked passage in the Hippocratic corpus].

    PubMed

    Villard, L

    1997-01-01

    A passage taken from the Hippocratic Corpus states that at the beginning of pregnancy women say that they do not like the taste of wine. This passage should be added to evidence about wine drinking by women in Classical Greece. It shows that, contrary to previous opinion, women drank wine when they were in good health and corresponds with the notion that it was often prescribed by physicians in order to cure illness.

  7. Abnormal hematological indices in cirrhosis

    PubMed Central

    Qamar, Amir A; Grace, Norman D

    2009-01-01

    Abnormalities in hematological indices are frequently encountered in cirrhosis. Multiple causes contribute to the occurrence of hematological abnormalities. Recent studies suggest that the presence of hematological cytopenias is associated with a poor prognosis in cirrhosis. The present article reviews the pathogenesis, incidence, prevalence, clinical significance and treatment of abnormal hematological indices in cirrhosis. PMID:19543577

  8. Annotated Chemical Patent Corpus: A Gold Standard for Text Mining

    PubMed Central

    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. 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.

  10. 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

  11. Formation and early development of the corpus luteum in pigs.

    PubMed

    Murphy, B D; Gévry, N; Ruiz-Cortés, T; Coté, F; Downey, B R; Sirois, J

    2001-01-01

    Numerous corpora lutea form from the multiple follicles that ovulate during the oestrous cycle of pigs. Vascular elements invade the follicle from the theca compartment, first centripetally, and subsequently by lateral branching of centripetal veins and arteries. The vessels are the vehicle for dispersion of steroidogenic theca cells throughout the corpus luteum. Mitosis occurs in both the theca and granulosa layers before ovulation, and in luteal cells well into the luteal phase. Luteal cell proliferation undergoes gradual restriction as the corpus luteum matures, but the mechanisms of exit from the cell cycle are unknown. The extracellular ligands that direct luteinization and maintain the corpus luteum include LH, prolactin, insulin and insulin-like growth factors (IGFs). These ligands induce qualitative and quantitative changes in steroid output, with progesterone as the principal product. These changes upregulate the cholesterol synthetic pathways to increase substrate availability. The intracellular regulation of luteinization is complex. A model is presented in which LH stimulates arachidonic and lineoleic acid metabolism to produce ligands for the nuclear proteins of the peripheral peroxisome activator receptor family. These ligands have downstream effects on cell differentiation and exit from the cell cycle. Luteal function is maintained by interactions among ligands, cholesterol regulatory proteins and constitutively expressed and regulated transcription factors. PMID:11980202

  12. Spirometric abnormalities among welders

    SciTech Connect

    Rastogi, S.K.; Gupta, B.N.; Husain, T.; Mathur, N.; Srivastava, S. )

    1991-10-01

    A group of manual welders age group 13-60 years having a mean exposure period of 12.4 {plus minus} 1.12 years were subjected to spirometry to evaluate the prevalence of spirometric abnormalities. The welders showed a significantly higher prevalence of respiratory impairment than that observed among the unexposed controls as a result of exposure to welding gases which comprised fine particles of lead, zinc, chromium, and manganese. This occurred despite the lower concentration of the pollutants at the work place. In the expose group, the smoking welders showed a prevalence of respiratory impairment significantly higher than that observed in the nonsmoking welders. The results of the pulmonary function tests showed a predominantly restrictive type of pulmonary impairment followed by a mixed ventilatory defect among the welders. The effect of age on pulmonary impairment was not discernible. Welders exposed for over 10 years showed a prevalence of respiratory abnormalities significantly higher than those exposed for less than 10 years. Smoking also had a contributory role.

  13. [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.

  14. Comparing English Vocabulary in a Spoken Learner Corpus with a Native Speaker Corpus: Pedagogical Implications Arising from an Empirical Study in Japan

    ERIC Educational Resources Information Center

    Shirato, Junko; Stapleton, Paul

    2007-01-01

    Insights from corpus linguistics have come to be seen as having a significant impact in second language pedagogy. Learner corpora, or collections of texts spoken or written by non-native speakers (NNS) of a language, are now being used for the purposes of enhancing language teaching. Specifically, by comparing the corpus of NNS with native…

  15. [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

  16. 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…

  17. Evaluation of the role of corpus cavernosum electromyography as a noninvasive diagnostic tool in male erectile dysfunction.

    PubMed

    Aggour, A; Mostafa, H; el-Shawaf, H

    1998-01-01

    Corpus cavernosum electromyography (EMG) and its evolution: single potential analysis of cavernous electrical activity (SPACE) seem to be promising diagnostic methods in the evaluation of erectile dysfunction and smooth muscle integrity. Our study concentrates on the role of EMG in the evaluation of corpus cavernosum smooth muscles, using it as a noninvasive technique for demonstrating autonomic erectile dysfunction through their influence on recording SPACE and consequent proper selection of patients for different therapeutic modalities. A total of 80 male patients were examined for the feasibility of transcutaneous registration of cavernous electrical activity with a 2-channel electrophysiological unit (Evamatic 2000, Dantec) with two surface electrodes bilaterally placed on the penile shaft. Ten patients had normal erectile function, but complained of other urological symptoms. They served as the controls for normal electrical activity. Fifty patients with organic impotence of nonvascular (neurogenic) or vascular (venogenic, arteriogenic) aetiologies were subjected to EMG in both the flaccid and the erect state. On the basis of the EMG patterns the patients were divided into the following groups: 34 patients having normal tracing in both the flaccid and the erect state, and 21 patients showing abnormal patterns of waves with evidence of autonomic neurogenic dysfunction and incomplete smooth muscle relaxation. Of the latter 4 had long-standing diabetes mellitus and 4 had spinal injuries. PMID:9569116

  18. A Rare Stapes Abnormality

    PubMed Central

    Kanona, Hala; Virk, Jagdeep Singh; Kumar, Gaurav; Chawda, Sanjiv; Khalil, Sherif

    2015-01-01

    The aim of this study is to increase awareness of rare presentations, diagnostic difficulties alongside management of conductive hearing loss and ossicular abnormalities. We report the case of a 13-year-old female reporting progressive left-sided hearing loss and high resolution computed tomography was initially reported as normal. Exploratory tympanotomy revealed an absent stapedius tendon and lack of connection between the stapes superstructure and footplate. The footplate was fixed. Stapedotomy and stapes prosthesis insertion resulted in closure of the air-bone gap by 50 dB. A review of world literature was performed using MedLine. Middle ear ossicular discontinuity can result in significant conductive hearing loss. This can be managed effectively with surgery to help restore hearing. However, some patients may not be suitable or decline surgical intervention and can be managed safely conservatively. PMID:25628909

  19. Corpus luteal contribution to maternal pregnancy physiology and outcomes in assisted reproductive technologies.

    PubMed

    Conrad, Kirk P; Baker, Valerie L

    2013-01-15

    Investigations in the rat model of pregnancy indicate an important role for the corpus luteal (CL) hormone relaxin in the maternal circulatory and osmoregulatory changes in pregnancy, which are epitomized by profound vasodilation and modest hypoosmolality, respectively. In a pilot study of infertile women who became pregnant through donor eggs, in vitro fertilization, and embryo transfer, the gestational rise in glomerular filtration and fall in plasma osmolality were markedly subdued. Because these women were infertile, they lacked a CL and circulating relaxin (and possibly other vasoactive CL hormones). Based on these findings in pregnant rats and women, we hypothesize that infertile women conceiving through donor eggs will have overall subdued circulatory changes (e.g., attenuated reduction in systemic vascular resistance and subdued increase in cardiac output) particularly during early pregnancy when CL hormones predominate before the full development and maturation of the placenta. In contrast, infertile women conceiving by autologous eggs retrieved after ovarian stimulation and fresh embryo transfer may have a relatively hyperdynamic circulation due to the presence of many CL (up to 20 or more) and higher circulating levels of vasodilatory ovarian hormones such as relaxin. Emerging evidence suggests that women undergoing Assisted Reproductive Technologies (ART) have increased risk for adverse pregnancy outcomes such as preeclampsia and small for gestational-age babies. This increased risk may be partly caused by the maternal milieu, which is not physiological in ART pregnancies due to the abnormal status of the CL.

  20. Ictal Cardiac Ryhthym Abnormalities

    PubMed Central

    Ali, Rushna

    2016-01-01

    Cardiac rhythm abnormalities in the context of epilepsy are a well-known phenomenon. However, they are under-recognized and often missed. The pathophysiology of these events is unclear. Bradycardia and asystole are preceded by seizure onset suggesting ictal propagation into the cortex impacting cardiac autonomic function, and the insula and amygdala being possible culprits. Sudden unexpected death in epilepsy (SUDEP) refers to the unanticipated death of a patient with epilepsy not related to status epilepticus, trauma, drowning, or suicide. Frequent refractory generalized tonic-clonic seizures, anti-epileptic polytherapy, and prolonged duration of epilepsy are some of the commonly identified risk factors for SUDEP. However, the most consistent risk factor out of these is an increased frequency of generalized tonic–clonic seizures (GTC). Prevention of SUDEP is extremely important in patients with chronic, generalized epilepsy. Since increased frequency of GTCS is the most consistently reported risk factor for SUDEP, effective seizure control is the most important preventive strategy. PMID:27347227

  1. Ictal Cardiac Ryhthym Abnormalities.

    PubMed

    Ali, Rushna

    2016-01-01

    Cardiac rhythm abnormalities in the context of epilepsy are a well-known phenomenon. However, they are under-recognized and often missed. The pathophysiology of these events is unclear. Bradycardia and asystole are preceded by seizure onset suggesting ictal propagation into the cortex impacting cardiac autonomic function, and the insula and amygdala being possible culprits. Sudden unexpected death in epilepsy (SUDEP) refers to the unanticipated death of a patient with epilepsy not related to status epilepticus, trauma, drowning, or suicide. Frequent refractory generalized tonic-clonic seizures, anti-epileptic polytherapy, and prolonged duration of epilepsy are some of the commonly identified risk factors for SUDEP. However, the most consistent risk factor out of these is an increased frequency of generalized tonic-clonic seizures (GTC). Prevention of SUDEP is extremely important in patients with chronic, generalized epilepsy. Since increased frequency of GTCS is the most consistently reported risk factor for SUDEP, effective seizure control is the most important preventive strategy. PMID:27347227

  2. Communication and abnormal behaviour.

    PubMed

    Crown, S

    1979-01-01

    In this paper the similarities between normal and abnormal behaviour are emphasized and selected aspects of communication, normal and aberrant, between persons are explored. Communication in a social system may be verbal or non-verbal: one person's actions cause a response in another person. This response may be cognitive, behavioural or physiological. Communication may be approached through the individual, the social situation or social interaction. Psychoanalysis approaches the individual in terms of the coded communications of psychoneurotic symptoms or psychotic behaviour; the humanist-existential approach is concerned more with emotional expression. Both approaches emphasize the development of individual identity. The interaction between persons and their social background is stressed. Relevant are sociological concepts such as illness behaviour, stigma, labelling, institutionalization and compliance. Two approaches to social interactions are considered: the gamesplaying metaphor, e.g. back pain as a psychosocial manipulation--the 'pain game'; and the 'spiral of reciprocal perspectives' which emphasizes the interactional complexities of social perceptions. Communicatory aspects of psychological treatments are noted: learning a particular metaphor such as 'resolution' of the problem (psychotherapy), learning more 'rewarding' behaviour (learning theory) or learning authenticity or self-actualization (humanist-existential).

  3. Communication and abnormal behaviour.

    PubMed

    Crown, S

    1979-01-01

    In this paper the similarities between normal and abnormal behaviour are emphasized and selected aspects of communication, normal and aberrant, between persons are explored. Communication in a social system may be verbal or non-verbal: one person's actions cause a response in another person. This response may be cognitive, behavioural or physiological. Communication may be approached through the individual, the social situation or social interaction. Psychoanalysis approaches the individual in terms of the coded communications of psychoneurotic symptoms or psychotic behaviour; the humanist-existential approach is concerned more with emotional expression. Both approaches emphasize the development of individual identity. The interaction between persons and their social background is stressed. Relevant are sociological concepts such as illness behaviour, stigma, labelling, institutionalization and compliance. Two approaches to social interactions are considered: the gamesplaying metaphor, e.g. back pain as a psychosocial manipulation--the 'pain game'; and the 'spiral of reciprocal perspectives' which emphasizes the interactional complexities of social perceptions. Communicatory aspects of psychological treatments are noted: learning a particular metaphor such as 'resolution' of the problem (psychotherapy), learning more 'rewarding' behaviour (learning theory) or learning authenticity or self-actualization (humanist-existential). PMID:261653

  4. Abnormal uterine bleeding.

    PubMed

    Whitaker, Lucy; Critchley, Hilary O D

    2016-07-01

    Abnormal uterine bleeding (AUB) is a common and debilitating condition with high direct and indirect costs. AUB frequently co-exists with fibroids, but the relationship between the two remains incompletely understood and in many women the identification of fibroids may be incidental to a menstrual bleeding complaint. A structured approach for establishing the cause using the Fédération International de Gynécologie et d'Obstétrique (FIGO) PALM-COEIN (Polyp, Adenomyosis, Leiomyoma, Malignancy (and hyperplasia), Coagulopathy, Ovulatory disorders, Endometrial, Iatrogenic and Not otherwise classified) classification system will facilitate accurate diagnosis and inform treatment options. Office hysteroscopy and increasing sophisticated imaging will assist provision of robust evidence for the underlying cause. Increased availability of medical options has expanded the choice for women and many will no longer need to recourse to potentially complicated surgery. Treatment must remain individualised and encompass the impact of pressure symptoms, desire for retention of fertility and contraceptive needs, as well as address the management of AUB in order to achieve improved quality of life. PMID:26803558

  5. Abortion for fetal abnormality.

    PubMed

    Maclean, N E

    1979-07-25

    I wish to thank Dr. Pauline Bennett for her reply (NZ Med J, 13 June). She has demonstrated well that in dealing with sensitive difficult issues such as abortion for fetal abnormality, the one thing the doctor is not recommended to do is to speak the truth] I am prompted to write this letter for 2 reasons. Firstly, the excellent letter written by Dr. A. M. Rutherford (NZ Med J, 13 June) on the subject of abortion stated, "The most disturbing feature about the whole controversy is the 'blunting of our conscience'." When the doctors are not encouraged to be honest with patients then indeed our conscience has been blunted. Secondly, I watched Holocaust last night, and cannot refrain from stating that I see frightening parallels between our liberal abortion policy and the activities of the Nazis. As I watched the "mental patients" being herded into the shed for gassing by the polite, tidy, white coated medical staff, and then heard the compassionate, sensitive, letter of the hospital authorities to the relatives of the deceased, the parallel became obvious. The mental patients were weak, defenseless, burdensome, and uneconomic; the unborn are weak, defenseless, burdensome, and uneconomic. The hospital authority's letter was acceptable in many ways, acceptable except that its words bore no relation to the truth. It is said that the "first casualty of war is the truth". Whether that war involves the Jews, or the insane, or the unborn, the statement would seem correct.

  6. Corpus analysis and automatic detection of emotion-including keywords

    NASA Astrophysics Data System (ADS)

    Yuan, Bo; He, Xiangqing; Liu, Ying

    2013-12-01

    Emotion words play a vital role in many sentiment analysis tasks. Previous research uses sentiment dictionary to detect the subjectivity or polarity of words. In this paper, we dive into Emotion-Inducing Keywords (EIK), which refers to the words in use that convey emotion. We first analyze an emotion corpus to explore the pragmatic aspects of EIK. Then we design an effective framework for automatically detecting EIK in sentences by utilizing linguistic features and context information. Our system outperforms traditional dictionary-based methods dramatically in increasing Precision, Recall and F1-score.

  7. Celsus and the Hippocratic Corpus: the originality of a 'plagiarist".

    PubMed

    Pardon, Muriel

    2005-01-01

    A study of all the passages connected to lippitudo and ophthalmia--Latin compilers used these two terms to refer to one and the same eye disease--shows that while Celsus claims to be a follower of Hippocrates, he does not mention some of the explanations which appear in his main sources. He both clarifies and completes the prescriptions of the 'Father of Medicine'. It can therefore be said that the De Medicina is a descendant of the Hippocratic Corpus in the same way as La Fontaine's Fables are a descendant of Aesop's. PMID:17144085

  8. 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.

  9. Haem degradation in abnormal haemoglobins.

    PubMed Central

    Brown, S B; Docherty, J C

    1978-01-01

    The coupled oxidation of certain abnormal haemoglobins leads to different bile-pigment isomer distributions from that of normal haemoglobin. The isomer pattern may be correlated with the structure of the abnormal haemoglobin in the neighbourhood of the haem pocket. This is support for haem degradation by an intramolecular reaction. PMID:708385

  10. Systemic abnormalities in liver disease

    PubMed Central

    Minemura, Masami; Tajiri, Kazuto; Shimizu, Yukihiro

    2009-01-01

    Systemic abnormalities often occur in patients with liver disease. In particular, cardiopulmonary or renal diseases accompanied by advanced liver disease can be serious and may determine the quality of life and prognosis of patients. Therefore, both hepatologists and non-hepatologists should pay attention to such abnormalities in the management of patients with liver diseases. PMID:19554648

  11. Abnormal pressure in hydrocarbon environments

    USGS Publications Warehouse

    Law, B.E.; Spencer, C.W.

    1998-01-01

    Abnormal pressures, pressures above or below hydrostatic pressures, occur on all continents in a wide range of geological conditions. According to a survey of published literature on abnormal pressures, compaction disequilibrium and hydrocarbon generation are the two most commonly cited causes of abnormally high pressure in petroleum provinces. In young (Tertiary) deltaic sequences, compaction disequilibrium is the dominant cause of abnormal pressure. In older (pre-Tertiary) lithified rocks, hydrocarbon generation, aquathermal expansion, and tectonics are most often cited as the causes of abnormal pressure. The association of abnormal pressures with hydrocarbon accumulations is statistically significant. Within abnormally pressured reservoirs, empirical evidence indicates that the bulk of economically recoverable oil and gas occurs in reservoirs with pressure gradients less than 0.75 psi/ft (17.4 kPa/m) and there is very little production potential from reservoirs that exceed 0.85 psi/ft (19.6 kPa/m). Abnormally pressured rocks are also commonly associated with unconventional gas accumulations where the pressuring phase is gas of either a thermal or microbial origin. In underpressured, thermally mature rocks, the affected reservoirs have most often experienced a significant cooling history and probably evolved from an originally overpressured system.

  12. Electrocardiograph abnormalities revealed during laparoscopy.

    PubMed

    Nijjer, Sukhjinder; Dubrey, Simon William

    2010-01-01

    This brief case presents a well patient in whom an electrocardiograph abnormality consistent with an accessory pathway was found during a routine procedure. We present the electrocardiographs, explain the underlying condition, and consider why the abnormality was revealed in this manner.

  13. Brief Report: Acrocallosal Syndrome and Autism

    ERIC Educational Resources Information Center

    Steiner, Carlos Eduardo; Guerreiro, Marilisa Mantovani; Marques-de-Faria, Antonia Paula

    2004-01-01

    The authors describe a boy presenting with acrocallosal syndrome and autism. Clinical features included craniofacial dysmorphisms, polydactyly, and mental retardation, besides behavioral symptoms compatible with autism. Neuroimaging revealed hypoplasia of the corpus callosum and cerebellar abnormalities. The role of this entity and other…

  14. Microphthalmia with linear skin defects syndrome.

    PubMed

    García-Rabasco, Ana; De-Unamuno, Blanca; Martínez, Francisco; Febrer-Bosch, Isabel; Alegre-de-Miquel, Víctor

    2013-01-01

    Microphthalmia with linear skin defects (MLS) or microcornea, dermal aplasia and sclerocornea (MIDAS) syndrome is a rare X-linked-dominant disorder. We present a patient with agenesis of corpus callosum, ocular abnormalities, and multiple skin defects. The cytogenetic studies of the MLS critical region (Xp22.2) were normal, but a skewed X-chromosome inactivation pattern (85:15) was observed.

  15. NEURONS COMPRISING A HETEROTOPIA INDUCED BY DEVELOPMENTAL HYPOTHYROIDISM ARE BORN LATE IN GESTATION.

    EPA Science Inventory

    We previously described an abnormal cluster of neurons, a heterotopia, located in the corpus callosum in rat pups born to dams exposed to the goitrogen, propylthiouracil (PTU, Goodman et al., SfN 2004). In this study we determined 1) whether the formation of the heterotopia was u...

  16. Language and Development in FG Syndrome with Callosal Agenesis.

    ERIC Educational Resources Information Center

    McCardle, Peggy; Wilson, Bruce

    1993-01-01

    The FG syndrome is characterized by unusual facies; sudden infant death; developmental delay; and abnormalities of the cardiac, gastrointestinal, and central nervous systems. Serial evaluations of one case with isolated agenesis of the corpus callosum found consistent patterns over time in specific language impairments in syntactic and…

  17. A Single Case-Study of Diagonistic Dyspraxia

    ERIC Educational Resources Information Center

    Barbeau, Emmanuel; Joubert, Sven; Poncet, Michel

    2004-01-01

    Diagonistic dyspraxia is a clinical syndrome usually characterized by involuntary and conflicting behaviors between the hands following corpus callosum lesions. In the present study, we report the case of a patient who presents such symptoms, along with a series of complex abnormal behaviors, such as carrying out an action and subsequently doing…

  18. 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…

  19. An Evaluation of an Online Bilingual Corpus for the Self-Learning of Legal English.

    ERIC Educational Resources Information Center

    Fan, May; Xunfeng, Xu

    2002-01-01

    Introduces a bilingual corpus of legal and documentary texts in English and Chinese and reports a study that sought to evaluate the usefulness of the corpus in the self-learning of legal English. Subjects were Chinese students doing a degree in translation at a university in Hong Kong, where English common law is still used since the handover of…

  20. Textual, Genre and Social Features of Spoken Grammar: A Corpus-Based Approach

    ERIC Educational Resources Information Center

    Perez-Llantada, Carmen

    2009-01-01

    This paper describes a corpus-based approach to teaching and learning spoken grammar for English for Academic Purposes with reference to Bhatia's (2002) multi-perspective model for discourse analysis: a textual perspective, a genre perspective and a social perspective. From a textual perspective, corpus-informed instruction helps students identify…

  1. 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…

  2. 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…

  3. 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…

  4. 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…

  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. 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…

  7. A Corpus-Based Study on English Prepositions of Place, "In" and "On"

    ERIC Educational Resources Information Center

    Arjan, Asmeza; Abdullah, Noor Hayati; Roslim, Norwati

    2013-01-01

    This corpus-based study examined the usage, mastery and developmental pattern (Norwati, 2004) of English prepositions of place, "in" and "on" across three different academic levels namely Form 4, Form 5 and College students. The Malaysian Corpus of Students Argumentative Writing (MCSAW) was used as the source of data in…

  8. 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…

  9. 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…

  10. 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…

  11. 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…

  12. Interface Conditions on Postverbal Subjects: A Corpus Study of L2 English

    ERIC Educational Resources Information Center

    Lozano, Cristobal; Mendikoetxea, Amaya

    2010-01-01

    This paper investigates how syntactic knowledge interfaces with other cognitive systems by analysing the production of postverbal subjects, V(erb)-S(ubject) order, in an L1 Spanish-L2 English corpus and a comparable English native corpus. VS order in both native and L2 English is shown to be constrained by properties operating at three interfaces:…

  13. 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…

  14. Linking Adverbials in First-Year Korean University EFL Learners' Writing: A Corpus-Informed Analysis

    ERIC Educational Resources Information Center

    Ha, Myung-Jeong

    2016-01-01

    This study examines the frequency and usage patterns of linking adverbials in Korean students' essay writing in comparison with native English writing. The learner corpus used in the present study is composed of 105 essays that were produced by first-year university students in Korea. The control corpus was taken from the American LOCNESS…

  15. 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…

  16. 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…

  17. Chromosomal abnormalities in human sperm

    SciTech Connect

    Martin, R.H.

    1985-01-01

    The ability to analyze human sperm chromosome complements after penetration of zona pellucida-free hamster eggs provides the first opportunity to study the frequency and type of chromosomal abnormalities in human gametes. Two large-scale studies have provided information on normal men. We have studied 1,426 sperm complements from 45 normal men and found an abnormality rate of 8.9%. Brandriff et al. (5) found 8.1% abnormal complements in 909 sperm from 4 men. The distribution of numerical and structural abnormalities was markedly dissimilar in the 2 studies. The frequency of aneuploidy was 5% in our sample and only 1.6% in Brandriff's, perhaps reflecting individual variability among donors. The frequency of 24,YY sperm was low: 0/1,426 and 1/909. This suggests that the estimates of nondisjunction based on fluorescent Y body data (1% to 5%) are not accurate. We have also studied men at increased risk of sperm chromosomal abnormalities. The frequency of chromosomally unbalanced sperm in 6 men heterozygous for structural abnormalities varied dramatically: 77% for t11;22, 32% for t6;14, 19% for t5;18, 13% for t14;21, and 0% for inv 3 and 7. We have also studied 13 cancer patients before and after radiotherapy and demonstrated a significant dose-dependent increase of sperm chromosome abnormalities (numerical and structural) 36 months after radiation treatment.

  18. Building an efficient curation workflow for the Arabidopsis literature corpus.

    PubMed

    Li, Donghui; Berardini, Tanya Z; Muller, Robert J; Huala, Eva

    2012-01-01

    TAIR (The Arabidopsis Information Resource) is the model organism database (MOD) for Arabidopsis thaliana, a model plant with a literature corpus of about 39 000 articles in PubMed, with over 4300 new articles added in 2011. We have developed a literature curation workflow incorporating both automated and manual elements to cope with this flood of new research articles. The current workflow can be divided into two phases: article selection and curation. Structured controlled vocabularies, such as the Gene Ontology and Plant Ontology are used to capture free text information in the literature as succinct ontology-based annotations suitable for the application of computational analysis methods. We also describe our curation platform and the use of text mining tools in our workflow. Database URL: www.arabidopsis.org PMID:23221298

  19. The Emergence of Texture: An Analysis of the Functions of the Nominal Demonstratives in English Interlanguage Corpus.

    ERIC Educational Resources Information Center

    Murphy, Terry

    2001-01-01

    Uses the concept of "emergent texture" to analyze the corpus behavior of the four nominal demonstratives--"this,""that,""these," an "those"--in an interlanguage corpus created at Yonsei University in Korea in 1999. Investigates a corpus of 109 single paragraphs. The concept of markedness is emphasized as a way of mediating the debate over the…

  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. Isolation of endothelial cells and pericytes from swine corpus luteum.

    PubMed

    Basini, G; Falasconi, I; Bussolati, S; Grolli, S; Ramoni, R; Grasselli, F

    2014-07-01

    From an angiogenesis perspective, the ovary offers a unique opportunity to study the physiological development of blood vessels. The first purpose of this work was to set up a protocol for the isolation of pig corpus luteum endothelial cells, which were characterized by both morphologic parameters and the expression of typical molecular markers; we also verified their ability to form capillary-like structures in a 3-dimensional matrix, their response to hypoxia and their migration in the presence of vascular endothelial growth factor (VEGF). The effectiveness of our isolation protocol was confirmed by the characteristic "cobblestone shape" of isolated cells at confluence as well as their expression of all the examined endothelial markers. Our data also showed a significant cell production of VEGF and nitric oxide. Isolated endothelial cells were also responsive to hypoxia by increasing the expression and production of VEGF and decreasing that of nitric oxide. In the angiogenesis bioassay, cells displayed the ability of forming capillary-like structures and also exhibited a significant migration in the scratch test. Our data suggest that the isolation of luteal endothelial cells represents a promising tool in experiments designed to clarify the biology of the angiogenic process. Furthermore, we have demonstrated that the isolated population comprises a subset of cells with a multidifferentiative capacity toward the chondrocytic and adipocytic phenotypes. These data suggest the presence of a perivascular or adventitial cell niche in the vascular wall of the corpus luteum populated with cells showing mesenchymal stem cell-like features, as already demonstrated for the adipose tissue and endometrium.

  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.

  3. 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.

  4. Neonatal White Matter Abnormalities an Important Predictor of Neurocognitive Outcome for Very Preterm Children

    PubMed Central

    Woodward, Lianne J.; Clark, Caron A. C.; Bora, Samudragupta; Inder, Terrie E.

    2012-01-01

    Background Cerebral white matter abnormalities on term MRI are a strong predictor of motor disability in children born very preterm. However, their contribution to cognitive impairment is less certain. Objective Examine relationships between the presence and severity of cerebral white matter abnormalities on neonatal MRI and a range of neurocognitive outcomes assessed at ages 4 and 6 years. Design/Methods The study sample consisted of a regionally representative cohort of 104 very preterm (≤32 weeks gestation) infants born from 1998–2000 and a comparison group of 107 full-term infants. At term equivalent, all preterm infants underwent a structural MRI scan that was analyzed qualitatively for the presence and severity of cerebral white matter abnormalities, including cysts, signal abnormalities, loss of white matter volume, ventriculomegaly, and corpus callosal thinning/myelination. At corrected ages 4 and 6 years, all children underwent a comprehensive neurodevelopmental assessment that included measures of general intellectual ability, language development, and executive functioning. Results At 4 and 6 years, very preterm children without cerebral white matter abnormalities showed no apparent neurocognitive impairments relative to their full-term peers on any of the domain specific measures of intelligence, language, and executive functioning. In contrast, children born very preterm with mild and moderate-to-severe white matter abnormalities were characterized by performance impairments across all measures and time points, with more severe cerebral abnormalities being associated with increased risks of cognitive impairment. These associations persisted after adjustment for gender, neonatal medical risk factors, and family social risk. Conclusions Findings highlight the importance of cerebral white matter connectivity for later intact cognitive functioning amongst children born very preterm. Preterm born children without cerebral white matter abnormalities on

  5. 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

  6. Corpus cavernosum abscess from a blind-ending urethra after urinary diversion surgery

    PubMed Central

    Kumabe, Ayako; Kenzaka, Tsuneaki; Yamamoto, Yu; Kajii, Eiji

    2013-01-01

    Corpus cavernosum abscesses are rarely seen in the clinical setting. We report the case of an early diagnosis of corpus cavernosum abscess due to a blind-ending urethra in a 60-year-old man without known risk factors and who was successfully treated by antibiotic therapy alone. In this case, the blind-ending urethra after urinary diversion surgery was considered a risk factor of the abscess formation. If the physician notes that the patient has fever of uncertain cause after urinary diversion surgery, he/she should examine the penis and perineum in consideration of the possibility of corpus cavernosum abscess. PMID:23616331

  7. Kidney transplantation in abnormal bladder

    PubMed Central

    Mishra, Shashi K.; Muthu, V.; Rajapurkar, Mohan M.; Desai, Mahesh R.

    2007-01-01

    Structural urologic abnormalities resulting in dysfunctional lower urinary tract leading to end stage renal disease may constitute 15% patients in the adult population and up to 20-30% in the pediatric population. A patient with an abnormal bladder, who is approaching end stage renal disease, needs careful evaluation of the lower urinary tract to plan the most satisfactory technical approach to the transplant procedure. Past experience of different authors can give an insight into the management and outcome of these patients. This review revisits the current literature available on transplantation in abnormal bladder and summarizes the clinical approach towards handling this group of difficult transplant patients. We add on our experience as we discuss the various issues. The outcome of renal transplant in abnormal bladder is not adversely affected when done in a reconstructed bladder. Correct preoperative evaluation, certain technical modification during transplant and postoperative care is mandatory to avoid complications. Knowledge of the abnormal bladder should allow successful transplantation with good outcome. PMID:19718334

  8. Expression of the human PAC1 receptor leads to dose-dependent hydrocephalus-related abnormalities in mice

    PubMed Central

    Lang, Bing; Song, Bing; Davidson, Wendy; MacKenzie, Alastair; Smith, Norman; McCaig, Colin D.; Harmar, Anthony J.; Shen, Sanbing

    2006-01-01

    Hydrocephalus is a common and potentially devastating birth defect affecting the CNS, and its relationship with G protein–coupled receptors (GPCRs) is unknown. We have expressed 2, 4, or 6 copies of a GPCR — the human PAC1 receptor with a 130-kb transgene in the mouse nervous system in a pattern closely resembling that of the endogenous gene. Consistent with PAC1 actions, PKA and PKC activity were elevated in the brains of Tg mice. Remarkably, Tg mice developed dose-dependent hydrocephalus-like characteristics, including enlarged third and lateral ventricles and reduced cerebral cortex, corpus callosum, and subcommissural organ (SCO). Neuronal proliferation and apoptosis were implicated in hydrocephalus, and we observed significantly reduced neuronal proliferation and massively increased neuronal apoptosis in the developing cortex and SCO of Tg embryos, while neurite outgrowth and neuronal migration in vitro remain uncompromised. Ventricular ependymal cilia are crucial for directing cerebrospinal fluid flow, and ependyma of Tg mice exhibited disrupted cilia with increased phospho-CREB immunoreactivity. These data demonstrate that altered neuronal proliferation/apoptosis and disrupted ependymal cilia are the main factors contributing to hydrocephalus in PAC1-overexpressing mice. This is the first report to our knowledge demonstrating that misregulation of GPCRs can be involved in hydrocephalus-related neurodevelopmental disorders. PMID:16823490

  9. Complex patterns of abnormal heartbeats

    NASA Technical Reports Server (NTRS)

    Schulte-Frohlinde, Verena; Ashkenazy, Yosef; Goldberger, Ary L.; Ivanov, Plamen Ch; Costa, Madalena; Morley-Davies, Adrian; Stanley, H. Eugene; Glass, Leon

    2002-01-01

    Individuals having frequent abnormal heartbeats interspersed with normal heartbeats may be at an increased risk of sudden cardiac death. However, mechanistic understanding of such cardiac arrhythmias is limited. We present a visual and qualitative method to display statistical properties of abnormal heartbeats. We introduce dynamical "heartprints" which reveal characteristic patterns in long clinical records encompassing approximately 10(5) heartbeats and may provide information about underlying mechanisms. We test if these dynamics can be reproduced by model simulations in which abnormal heartbeats are generated (i) randomly, (ii) at a fixed time interval following a preceding normal heartbeat, or (iii) by an independent oscillator that may or may not interact with the normal heartbeat. We compare the results of these three models and test their limitations to comprehensively simulate the statistical features of selected clinical records. This work introduces methods that can be used to test mathematical models of arrhythmogenesis and to develop a new understanding of underlying electrophysiologic mechanisms of cardiac arrhythmia.

  10. 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

  11. [Emotion Disorders and Abnormal Perspiration].

    PubMed

    Umeda, Satoshi

    2016-08-01

    This article reviewed the relationship between emotional disorders and abnormal perspiration. First, I focused on local brain areas related to emotional processing, and summarized the functions of the emotional network involving those local areas. Functional disorders followed by the damage in the amygdala, orbitofrontal cortex, and insular cortex were reviewed, including related abnormal perspiration. I then addressed the mechanisms of how autonomic disorders influence emotional processing. Finally, possible future directions for integrated understanding of the connection between neural activities and bodily reactions were discussed. PMID:27503817

  12. [Emotion Disorders and Abnormal Perspiration].

    PubMed

    Umeda, Satoshi

    2016-08-01

    This article reviewed the relationship between emotional disorders and abnormal perspiration. First, I focused on local brain areas related to emotional processing, and summarized the functions of the emotional network involving those local areas. Functional disorders followed by the damage in the amygdala, orbitofrontal cortex, and insular cortex were reviewed, including related abnormal perspiration. I then addressed the mechanisms of how autonomic disorders influence emotional processing. Finally, possible future directions for integrated understanding of the connection between neural activities and bodily reactions were discussed.

  13. 33 CFR 165.809 - Security Zones; Port of Port Lavaca-Point Comfort, Point Comfort, TX and Port of Corpus Christi...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Security Zones; Port of Port Lavaca-Point Comfort, Point Comfort, TX and Port of Corpus Christi Inner Harbor, Corpus Christi, TX. 165... Lavaca-Point Comfort, Point Comfort, TX and Port of Corpus Christi Inner Harbor, Corpus Christi, TX....

  14. 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.

  15. Identification and interpretation of microstructural abnormalities in motor pathways in adolescents born preterm.

    PubMed

    Groeschel, Samuel; Tournier, J-Donald; Northam, Gemma B; Baldeweg, Torsten; Wyatt, John; Vollmer, Brigitte; Connelly, Alan

    2014-02-15

    There has been extensive interest in assessing the long-term effects of preterm birth on brain white matter microstructure using diffusion MRI. Our aim in this study is to explore diffusion MRI differences between adolescents born preterm and term born controls, with a specific interest in characterising how such differences are manifested in white matter regions containing predominantly single or crossing fibre populations. Probabilistic high angular resolution tractography together with large deformation spatial normalisation were used to objectively investigate diffusion tensor parameters at regular intervals along fibre tracts of 45 adolescents born before 33 weeks of gestation and 30 term-born typically developing adolescents. Diffusion parameters were significantly different between preterms and controls at several levels along the cortico-spinal, thalamo-cortical and transcallosal pathways. Within the predominantly single fibre regions of the corpus callosum and internal capsule, in the preterms mean diffusivity (MD) was found to be increased while fractional anisotropy (FA) was decreased compared to controls. In contrast, however, where these pathways traversed the centrum semiovale, FA and MD were both significantly increased. The major contributor to reduced FA in preterms in predominantly single fibre regions was the increased radial eigenvalue (i.e. increased radial diffusivity). In predominantly crossing-fibre regions, the tensor eigenvalues are not meaningful, and the observed increase in FA is likely to be due to a decrease in anisotropy in one of the contributing fibre bundles. Similar differences (although less pronounced) were observed after excluding preterms with radiological signs of preterm brain injury from the sample. In summary, white matter microstructure was found to be altered in motor pathways in adolescents born preterm. Disruption of white matter (WM) microstructure in a single fibre region with resulting higher radial diffusivity

  16. Data modelling in corpus linguistics: how low may we go?

    PubMed

    van Velzen, Marjolein H; Nanetti, Luca; de Deyn, Peter P

    2014-06-01

    Corpus linguistics allows researchers to process millions of words. However, the more words we analyse, i.e., the more data we acquire, the more urgent the call for correct data interpretation becomes. In recent years, a number of studies saw the light attempting to profile some prolific authors' linguistic decline, linking this decline to pathological conditions such as Alzheimer's Disease (AD). However, in line with the nature of the (literary) work that was analysed, numbers alone do not suffice to 'tell the story'. The one and only objective of using statistical methods for the analysis of research data is to tell a story--what happened, when, and how. In the present study we describe a computerised but individualised approach to linguistic analysis--we propose a unifying approach, with firm grounds in Information Theory, that, independently from the specific parameter being investigated, guarantees to produce a robust model of the temporal dynamics of an author's linguistic richness over his or her lifetime. We applied this methodology to six renowned authors with an active writing life of four decades or more: Iris Murdoch, Gerard Reve, Hugo Claus, Agatha Christie, P.D. James, and Harry Mulisch. The first three were diagnosed with probable Alzheimer Disease, confirmed post-mortem for Iris Murdoch; this same condition was hypothesized for Agatha Christie. Our analysis reveals different evolutive patterns of lexical richness, in turn plausibly correlated with the authors' different conditions.

  17. Effect of avanafil on rat and human corpus cavernosum.

    PubMed

    Gur, S; Sikka, S C; Pankey, E A; Lasker, G F; Chandra, S; Kadowitz, P J; Hellstrom, W J G

    2015-10-01

    We compared the activity of a new phosphodiesterase-5 inhibitor (PDE5i) avanafil with sildenafil and tadalafil in human and rat corpus cavernosum (CC) tissues. The effect of avanafil with several inhibitors and electrical field stimulation (EFS) was evaluated on CC after pre-contraction with phenylephrine. With the PDE5i, sildenafil and tadalafil, concentration-response curves were obtained and cyclic guanosine monophosphate (cGMP) levels were measured in tissues. Avanafil induced relaxation with maximum response of 74 ± 5% in human CC. This response was attenuated by NOS inhibitor and soluble guanylate cyclase (sGC) inhibitor. Avanafil potentiated relaxation responses to acetylcholine and EFS in human CC and enhanced SNP-induced relaxation and showed 3-fold increase in cGMP levels. When compared with sildenafil, avanafil and tadalafil were effective at lower concentrations in human CC. In addition, Sprague-Dawley rats underwent in vivo intracavernosal pressure (ICP) and mean arterial pressure (MAP) measurements. Avanafil increased ICP/MAP that was enhanced by SNP and cavernous nerve (CN) stimulation in rat CC tissues. Also avanafil showed maximum relaxation response of 83 ± 7% in rat CC with 3-fold increase in cGMP concentration. Taken together, these results of our in vivo and in vitro studies in human and rat suggest that avanafil promotes the CC relaxation and penile erection via NO-cGMP pathway.

  18. 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

  19. 5-HT4 receptors in isolated human corpus cavernosum?

    PubMed

    Hayes, E S; Adaikan, P G; Ratnam, S S; Ng, S C

    1999-08-01

    The novel serotonin subtype-4 (5-HT4) receptor agonist, SC53116 (SC), produced a limited relaxation of noradrenaline (NA) pre-contracted human corpus cavernosum (CC) smooth muscle in vitro. This effect was not significantly attenuated by the 5-HT4 antagonist SDZ250557 (SDZ). In the presence of (+/-) pindolol (1 microM) and methysergide (1 microM), employed to mask 5-HT1 and beta-adrenergic, and 5-HT2 receptors respectively, SC failed to relax NA pre-contracted CC strips to a greater extent than saline. Functional cAMP dependent relaxation pathways were demonstrated by a significant reduction in NA induced tone by prostaglandin E1 (PGE1) and isopropylnoradrenaline (IPNA), the action of the latter compound was effectively eliminated in the presence of (+/-) pindolol. Relaxation of NA induced tone caused by the nitric oxide donor nitro-glycerine (NTG) was significant and similar in the absence and presence of the 5-HT and beta-adrenergic antagonists. The results of this present study indicate that human corporal smooth muscle does not contain 5-HT4 receptors and that, although compounds like SC act to relax non-vascular smooth muscle via cAMP dependent mechanisms, 5-HT4 receptor agonists may be expected to be of limited utility in triggering cAMP dependent relaxation responses in human CC.

  20. 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

  1. 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/.

  2. 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

  3. Electrocardiograph abnormalities in intracerebral hemorrhage.

    PubMed

    Takeuchi, Satoru; Nagatani, Kimihiro; Otani, Naoki; Wada, Kojiro; Mori, Kentaro

    2015-12-01

    This study investigated the prevalence and type of electrocardiography (ECG) abnormalities, and their possible association with the clinical/radiological findings in 118 consecutive patients with non-traumatic, non-neoplastic intracerebral hemorrhage (ICH). ECG frequently demonstrates abnormalities in patients with ischemic stroke and subarachnoid hemorrhage, but little is known of ECG changes in ICH patients. Clinical and radiological information was retrospectively reviewed. ECG recordings that were obtained within 24 hours of the initial hemorrhage were analyzed. Sixty-six patients (56%) had one or more ECG abnormalities. The most frequent was ST depression (24%), followed by left ventricular hypertrophy (20%), corrected QT interval (QTc) prolongation (19%), and T wave inversion (19%). The logistic regression analysis demonstrated the following: insular involvement was an independent predictive factor of ST depression (p<0.001; odds ratio OR 10.18; 95% confidence interval [CI] 2.84-36.57); insular involvement (p<0.001; OR 23.98; 95% CI 4.91-117.11) and presence of intraventricular hemorrhage (p<0.001; OR 8.72; 95% CI 2.69-28.29) were independent predictive factors of QTc prolongation; deep hematoma location (p<0.001; OR 19.12; 95% CI 3.82-95.81) and hematoma volume >30 ml (p=0.001; OR 6.58; 95% CI 2.11-20.46) were independent predictive factors of T wave inversion. We demonstrate associations between ECG abnormalities and detailed characteristics of ICH.

  4. 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

  5. Transcriptome signatures in Helicobacter pylori-infected mucosa identifies acidic mammalian chitinase loss as a corpus atrophy marker

    PubMed Central

    2013-01-01

    Background The majority of gastric cancer cases are believed to be caused by chronic infection with the bacterium Helicobacter pylori, and atrophic corpus gastritis is a predisposing condition to gastric cancer development. We aimed to increase understanding of the molecular details of atrophy by performing a global transcriptome analysis of stomach tissue. Methods Biopsies from patients with different stages of H. pylori infection were taken from both the antrum and corpus mucosa and analyzed on microarrays. The stages included patients without current H. pylori infection, H. pylori-infected without corpus atrophy and patients with current or past H. pylori-infection with corpus-predominant atrophic gastritis. Results Using clustering and integrated analysis, we found firm evidence for antralization of the corpus mucosa of atrophy patients. This antralization harbored gain of gastrin expression, as well as loss of expression of corpus-related genes, such as genes associated with acid production, energy metabolism and blood clotting. The analyses provided detailed molecular evidence for simultaneous intestinal metaplasia (IM) and spasmolytic polypeptide expressing metaplasia (SPEM) in atrophic corpus tissue. Finally, acidic mammalian chitinase, a chitin-degrading enzyme produced by chief cells, was shown to be strongly down-regulated in corpus atrophy. Conclusions Transcriptome analysis revealed several gene groups which are related to development of corpus atrophy, some of which were increased also in H. pylori-infected non-atrophic patients. Furthermore, loss of acidic chitinase expression is a promising marker for corpus atrophy. PMID:24119614

  6. 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…

  7. [Transient abnormal Q-waves].

    PubMed

    Godballe, C; Hoeck, H C; Sørensen, J A

    1990-01-01

    We present a case of transient abnormal Q-waves (TAQ) and a review of the literature. TAQ are defined as abnormal Q-waves, which disappear within ten days. They are most often seen in patients with ischemic heart disease (IHD) but are also seen in other conditions. Brief episodes of myocardial ischemia giving rise to reversible biochemical and ultrastructural myocardial changes, resulting in transient ECG changes, provide an accepted theory for the pathogenesis of TAO. Investigations have shown that the occurrence of exercise-induced TAQ may be a symptom of IHD. It is impossible to distinguish TAQ from Q-waves induced by myocardial infarction. Appearance of TAQ during exercise-testing frequently indicates IHD. PMID:2301045

  8. [Chromosome abnormalities in human cancer].

    PubMed

    Salamanca-Gómez, F

    1995-01-01

    Recent investigation on the presence of chromosome abnormalities in neoplasias has allowed outstanding advances in the knowledge of malignant transformation mechanisms and important applications in the clinical diagnosis and prognosis of leukaemias, lymphomas and solid tumors. The purpose of the present paper is to discuss the most relevant cytogenetic aberrations, some of them described at the Unidad de Investigación Médica en Genética Humana, Instituto Mexicano del Seguro Social, and to correlate these abnormalities with recent achievements in the knowledge of oncogenes, suppressor genes or antioncogenes, their chromosome localization, and their mutations in human neoplasia; as well as their perspectives in prevention and treatment of cancer that such findings permit to anticipate.

  9. Ultrasound screening for fetal abnormalities.

    PubMed

    Chitty, L S

    1995-12-01

    Ultrasound screening for fetal abnormalities is increasingly becoming part of routine antenatal care in Europe and the UK. However, there has been very little formal evaluation of this practice. In this article reports of routine ultrasound screening are reviewed and the advantages and disadvantages discussed. The majority of routine anomaly scanning is done in the second trimester but there may be a case for screening at other times in pregnancy and alternative anomaly screening policies are discussed. PMID:8710765

  10. [Endocrine abnormalities in HIV infections].

    PubMed

    Verges, B; Chavanet, P; Desgres, J; Kisterman, J P; Waldner, A; Vaillant, G; Portier, H; Brun, J M; Putelat, R

    The finding of endocrine gland lesions at pathological examination in AIDS and reports of several cases of endocrine disease in patients with this syndrome have prompted us to study endocrine functions in 63 patients (51 men, 12 women) with HIV-1 infection. According to the Center for Disease Control (CDC) classification system, 13 of these patients were stage CDC II, 27 stage CDC III and 23 stage CDC IV. We explored the adrenocortical function (ACTH, immediate tetracosactrin test) and the thyroid function (free T3 and T4 levels, TRH on TSH test) in all 63 patients. The hypothalamic-pituitary-gonadal axis (testosterone levels, LHRH test) and prolactin secretion (THR test) were explored in the 51 men. The results obtained showed early peripheral testicular insufficiency at stage CDC II and early pituitary gland abnormalities with hypersecretion of ACTH and prolactin also at stage CDC II. On the other hand, adrenocortical and pituitary abnormalities were not frequently found. The physiopathology of the endocrine abnormalities observed in HIV-1-infected patients remains unclear, but one may suspect that it involves interleukin-1 since this protein factor has recently been shown to stimulate the corticotropin-releasing hormone secretion and to act directly on the glycoprotein capsule of the virus (gp 120) whose structure is similar to that of some neurohormones.

  11. 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.

  12. 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

  13. 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

  14. 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

  15. 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.

  16. Making chromosome abnormalities treatable conditions.

    PubMed

    Cody, Jannine DeMars; Hale, Daniel Esten

    2015-09-01

    Individuals affected by the classic chromosome deletion syndromes which were first identified at the beginning of the genetic age, are now positioned to benefit from genomic advances. This issue highlights five of these conditions (4p-, 5p-, 11q-, 18p-, and 18q-). It focuses on the increased in understanding of the molecular underpinnings and envisions how these can be transformed into effective treatments. While it is scientifically exciting to see the phenotypic manifestations of hemizygosity being increasingly understood at the molecular and cellular level, it is even more amazing to consider that we are now on the road to making chromosome abnormalities treatable conditions.

  17. [Erythrocyte membrane abnormalities - hereditary elliptocytosis].

    PubMed

    Kvezereli-Kopadze, M; Kvezereli-Kopadze, A; Mtvarelidze, Z; Bubuteishvili, A

    2015-04-01

    This study was designed to investigate the 4 year old boy with Hereditary Elliptocitosis (HE). The diagnosis of this rare hemolytic anemia was based on detailed family history (positive in the 4-th generation), physical examination and Para-clinical data analyses. The vast majority of patients with HE are asymptomatic, severe forms are rare. The most important is examination of blood films, which is helpful to detect the morphology abnormalities of red cells. In case of HE a different approach is required. Positive family history and series of investigations should be conducted to determine the HE.

  18. Abnormalities of the erythrocyte membrane.

    PubMed

    Gallagher, Patrick G

    2013-12-01

    Primary abnormalities of the erythrocyte membrane are characterized by clinical, laboratory, and genetic heterogeneity. Among this group, hereditary spherocytosis patients are more likely to experience symptomatic anemia. Treatment of hereditary spherocytosis with splenectomy is curative in most patients. Growing recognition of the long-term risks of splenectomy has led to re-evaluation of the role of splenectomy. Management guidelines acknowledge these considerations and recommend discussion between health care providers, patient, and family. The hereditary elliptocytosis syndromes are the most common primary disorders of erythrocyte membrane proteins. However, most elliptocytosis patients are asymptomatic and do not require therapy.

  19. Foot abnormalities of wild birds

    USGS Publications Warehouse

    Herman, C.M.; Locke, L.N.; Clark, G.M.

    1962-01-01

    The various foot abnormalities that occur in birds, including pox, scaly-leg, bumble-foot, ergotism and freezing are reviewed. In addition, our findings at the Patuxent Wildlife Research Center include pox from dove, mockingbird, cowbird, grackle and several species of sparrows. Scaly-leg has been particularly prevalent on icterids. Bumble foot has been observed in a whistling swan and in a group of captive woodcock. Ergotism is reported from a series of captive Canada geese from North Dakota. Several drug treatments recommended by others are presented.

  20. Trends in cancer incidence in female breast, cervix uteri, corpus uteri, and ovary in India.

    PubMed

    Yeole, Balkrishna B

    2008-01-01

    Trends in breast, cervix uteri, corpus uteri and ovarian cancers in six population based cancer registries (Mumbai, Bangalore, Chennai, Delhi, Bhopal, and Barshi) were evaluated over a period of the last two decades. For studying trends we used a model that fits this data is the logarithm of Y=ABx which represents a Linear Regression model. This approach showed a decreasing trend for cancer of the cervix and increasing trends for cancers of breast, ovary and corpus uteri throughout the entire period of observation in most of the registries. The four cancers, breast, cervix, corpus uteri and ovary, constitute more than 50% of total cancers in women. As all these cancers are increasing, to understand their etiology in depth, analytic epidemiology studies should be planned in a near future on a priority basis.