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Sample records for abnormal corpus callosum

  1. Interhemispheric functional disconnection because of abnormal corpus callosum integrity in bipolar disorder type II

    PubMed Central

    Kudo, Takashi; Matsuoka, Kiwamu; Yamamoto, Akihide; Takahashi, Masato; Nakagawara, Jyoji; Nagatsuka, Kazuyuki; Iida, Hidehiro; Kishimoto, Toshifumi

    2016-01-01

    Background A significantly lower fractional anisotropy (FA) value has been shown in anterior parts of the corpus callosum in patients with bipolar disorder. Aims We investigated the association between abnormal corpus callosum integrity and interhemispheric functional connectivity (IFC) in patients with bipolar disorder. Methods We examined the association between FA values in the corpus callosum (CC-FA) and the IFC between homotopic regions in the anterior cortical structures of bipolar disorder (n=16) and major depressive disorder (n=22) patients with depressed or euthymic states. Results We found a positive correlation between the CC-FA and IFC values between homotopic regions of the ventral prefrontal cortex and insula cortex, and significantly lower IFC between these regions in bipolar disorder patients. Conclusions The abnormal corpus callosum integrity in bipolar disorder patients is relevant to the IFC between homotopic regions, possibly disturbing the exchange of emotional information between the cerebral hemispheres resulting in emotional dysregulation. Declaration of interest None. Copyright and usage © The Royal College of Psychiatrists 2016. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) license. PMID:27847590

  2. 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…

  3. 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.

  4. Abnormal pathways in the genu of the corpus callosum in schizophrenia pathogenesis: a proteome study.

    PubMed

    Sivagnanasundaram, Sinthuja; Crossett, Ben; Dedova, Irina; Cordwell, Stuart; Matsumoto, Izuru

    2007-10-01

    Abnormalities within the corpus callosum (CC) have been identified in schizophrenia brains and are thought to affect inter-hemispheric communication, which in-turn is postulated to underlie some schizophrenia symptoms. Furthermore, hemisphere asymmetry of fractional anisotropy, detected by diffusion tensor imaging, left-higher-than-right- has been observed in normal individuals in the CC genu. This asymmetry is significantly reduced in the left CC genu of first-episode and chronic schizophrenia subjects. We examined the protein expression profile of the CC genu, including the profiles from the left and right hemisphere, in schizophrenia brains compared to controls using two-dimensional gel electrophoresis and mass spectrometry techniques. Proteins involved in cytoskeletal structure and function, neuroprotective function and energy metabolism were identified as differentially expressed, suggesting these proteins may underlie abnormal CC genu structure and function. Proteins in these functional categories also displayed different expression levels in the left CC genu compared to the right in both control and schizophrenia brains and therefore may be involved in normal CC asymmetry and reduced asymmetry in schizophrenia individuals. This initial pool of protein candidates and abnormal functional pathways opens up avenues for further investigation of molecular mechanisms involving the CC in schizophrenia pathogenesis and symptoms.

  5. 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…

  6. Corpus callosum abnormalities, intellectual disability, speech impairment, and autism in patients with haploinsufficiency of ARID1B.

    PubMed

    Halgren, C; Kjaergaard, S; Bak, M; Hansen, C; El-Schich, Z; Anderson, C M; Henriksen, K F; Hjalgrim, H; Kirchhoff, M; Bijlsma, E K; Nielsen, M; den Hollander, N S; Ruivenkamp, C A L; Isidor, B; Le Caignec, C; Zannolli, R; Mucciolo, M; Renieri, A; Mari, F; Anderlid, B-M; Andrieux, J; Dieux, A; Tommerup, N; Bache, I

    2012-09-01

    Corpus callosum abnormalities, intellectual disability, speech impairment, and autism in patients with haploinsufficiency of ARID1B. Corpus callosum abnormalities are common brain malformations with a wide clinical spectrum ranging from severe intellectual disability to normal cognitive function. The etiology is expected to be genetic in as much as 30-50% of the cases, but the underlying genetic cause remains unknown in the majority of cases. By next-generation mate-pair sequencing we mapped the chromosomal breakpoints of a patient with a de novo balanced translocation, t(1;6)(p31;q25), agenesis of corpus callosum (CC), intellectual disability, severe speech impairment, and autism. The chromosome 6 breakpoint truncated ARID1B which was also truncated in a recently published translocation patient with a similar phenotype. Quantitative polymerase chain reaction (Q-PCR) data showed that a primer set proximal to the translocation showed increased expression of ARID1B, whereas primer sets spanning or distal to the translocation showed decreased expression in the patient relative to a non-related control set. Phenotype-genotype comparison of the translocation patient to seven unpublished patients with various sized deletions encompassing ARID1B confirms that haploinsufficiency of ARID1B is associated with CC abnormalities, intellectual disability, severe speech impairment, and autism. Our findings emphasize that ARID1B is important in human brain development and function in general, and in the development of CC and in speech development in particular.

  7. Humero-radial synostosis, microcephaly, short corpus callosum, and abnormal genitalia in sibs.

    PubMed

    Guilherme, Romain; Baumann, Clarisse; Garel, Catherine; Huten, Yolène; Oury, Jean-François; Delezoide, Anne-Lise

    2008-07-15

    We report on two male sib fetuses with humero-radial synostosis and thumb hypoplasia, microcephaly with simplified gyral pattern, short corpus callosum and ambiguous genitalia. The main clinical, anatomopathological and imaging findings are presented and compared with previous cases of humero-radial synostosis as a prominent manifestation and with the X-linked lissencephaly with ambiguous genitalia syndrome (X-LAG). To our knowledge, this combination of anomalies has never been described before, and we propose that this disorder comprises a new humero-radial synostosis syndrome with an autosomal recessive or X-linked pattern of inheritance.

  8. 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

  9. Delusional Disorder in a Patient with Corpus Callosum Agenesis.

    PubMed

    Bhatia, M S; Saha, Rashmita; Doval, Nimisha

    2016-12-01

    Agenesis of corpus callosum is rare and associated neuropsychiatric abnormalities reported are epilepsy, Asperger's syndrome, learning problems, depression, schizophrenia, conduct disorder and conversion symptoms. Schizophrenia is the most common psychiatric disorder reported among corpus callosum agenesis. We report a rare case of delusional disorder with corpus callosum agenesis and seizure disorder. The patient presented with delusions of persecution towards younger brother and mother, disturbed sleep and reduced appetite. She had a history of seizure disorder of ten years duration, which was controlled with carbamazepine and levetiracetam. Neurological examination was normal. On MRI, corpus callosum agenesis was detected. She was put on an atypical antipsychotic quetiapine to which her psychiatric symptoms responded completely.

  10. [Modern diagnostic of agenesis of the corpus callosum in children].

    PubMed

    Milovanova, O A; Alikhanov, A A; Tambiev, I E; Tarakanova, T Yu

    2017-01-01

    Observations of the authors regarding main MRI symptoms of agenesis of the corpus callosum (ACC) and literature review on the structure of the corpus callosum in normalcy and pathology are presented. The authors emphasize that some cases of isolated ACC has been found during routine prenatal ultrasound examination. In this regard, prenatal MRI is more effective. In 74% patients with ACC, MRI results are consistent with the results of ultrasound and CT. MRI has advantages in the differentiation of inherited corpus callosum malformation as well as concomitant CNS abnormalities.

  11. 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…

  12. Delusional Disorder in a Patient with Corpus Callosum Agenesis

    PubMed Central

    Saha, Rashmita; Doval, Nimisha

    2016-01-01

    Agenesis of corpus callosum is rare and associated neuropsychiatric abnormalities reported are epilepsy, Asperger’s syndrome, learning problems, depression, schizophrenia, conduct disorder and conversion symptoms. Schizophrenia is the most common psychiatric disorder reported among corpus callosum agenesis. We report a rare case of delusional disorder with corpus callosum agenesis and seizure disorder. The patient presented with delusions of persecution towards younger brother and mother, disturbed sleep and reduced appetite. She had a history of seizure disorder of ten years duration, which was controlled with carbamazepine and levetiracetam. Neurological examination was normal. On MRI, corpus callosum agenesis was detected. She was put on an atypical antipsychotic quetiapine to which her psychiatric symptoms responded completely. PMID:28208982

  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. Fiber composition of the human corpus callosum.

    PubMed

    Aboitiz, F; Scheibel, A B; Fisher, R S; Zaidel, E

    1992-12-11

    The densities of fibers of different sizes were calculated in ten regions of the corpus callosum of twenty human brains (ten females, ten males). Light microscopic examination revealed a consistent pattern of regional differentiation of fiber types in the corpus callosum. Thin fibers are most dense in the anterior corpus callosum (genu), and decrease in density posteriorly towards the posterior midbody, where they reach a minimum. Towards the posterior corpus callosum (splenium), the density of thin fibers increases again, but in the posterior pole of the callosum the density decreases locally. Large-diameter fibers show a pattern complementary to that of thin fibers, having a peak of density in the posterior midbody and a local increase of density in the posterior pole of the corpus callosum. Across subjects, the overall density of callosal fibers had no significant correlation with callosal area and an increased callosal area indicated an increased total number of fibers crossing through. Considering different fiber sizes, this was only true for small diameter fibers, whose large majority is believed to interconnect association cortex. No sex differences in fiber composition of the corpus callosum were found.

  15. 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

  16. Abnormal corpus callosum connectivity, socio-communicative deficits, and motor deficits in children with autism spectrum disorder: a diffusion tensor imaging study.

    PubMed

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

    2014-09-01

    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 whether abnormalities of the CC were related to motor deficits, as well as social and communication deficits in children with ASD. The ASD group displayed abnormal macro and microstructure of the total CC and its subdivisions and its structural properties were related to socio-communicative deficits, but not to motor deficits in ASD. These findings advance our understanding of the contributions of the CC to ASD symptoms.

  17. 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.

  18. 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.

  19. 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…

  20. Partial agenesis of corpus callosum--case study.

    PubMed

    Zamurović, M; Andjelic, S

    2014-01-01

    Agenesis of the corpus callosum is an uncommon cerebral malformation usually of unknown etiology. It can be associated with other brain abnormalities, such as ventriculomegaly, or in combination with problems with other organs, such as congenital heart defect, as well as with chromosome anomalies. Diagnosis of this rare anomaly is important not only because of possible association with other developmental anomalies but also because of postnatal treatment and evaluation of children with this disorder. This paper presents prenatal diagnosis of partial agenesis of the posterior part of corpus callosum of a fetus detected in gestational week 33 by ultrasonography as an isolated developmental disorder, i.e., not accompanied by other morphological anomalies of the fetus or chromosome aberrations or other genetic defects.

  1. 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.

  2. Ultrasound measurement of the corpus callosum and neural development of premature infants.

    PubMed

    Liu, Fang; Cao, Shikao; Liu, Jiaoran; Du, Zhifang; Guo, Zhimei; Ren, Changjun

    2013-09-15

    Length and thickness of 152 corpus callosa were measured in neonates within 24 hours of birth. Using ultrasonic diagnostic equipment with a neonatal brain-specific probe, corpus callosum length and thickness of the genu, body, and splenium were measured on the standard mid-sagittal plane, and the anteroposterior diameter of the genu was measured in the coronal plane. Results showed that corpus callosum length as well as thickness of the genu and splenium increased with tional age and birth weight, while other measures did not. These three factors on the standard mid-sagittal plane are therefore likely to be suitable for real-time evaluation of corpus callosum velopment in premature infants using cranial ultrasound. Further analysis revealed that thickness of the body and splenium and the anteroposterior diameter of the genu were greater in male infants than in female infants, suggesting that there are sex differences in corpus callosum size during the neonatal period. A second set of measurements were taken from 40 premature infants whose gestational age was 34 weeks or less. Corpus callosum measurements were corrected to a gestational age of 40 weeks, and infants were grouped for analysis depending on the outcome of a neonatal behavioral neurological assessment. Compared with infants with a normal neurological assessment, corpus callosum length and genu and splenium thicknesses were less in those with abnormalities, indicating that corpus callosum growth in premature infants is associated with neurobehavioral development during the early extrauterine stage.

  3. 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.

  4. Clinics in diagnostic imaging (175). Corpus callosum glioblastoma multiforme (GBM): butterfly glioma.

    PubMed

    Krishnan, Vijay; Lim, Tze Chwan; Ho, Francis Cho Hao; Peh, Wilfred Cg

    2017-03-01

    A 54-year-old man presented with change in behaviour, nocturnal enuresis, abnormal limb movement and headache of one week's duration. The diagnosis of butterfly glioma (glioblastoma multiforme) was made based on imaging characteristics and was further confirmed by biopsy findings. As the corpus callosum is usually resistant to infiltration by tumours, a mass that involves and crosses the corpus callosum is suggestive of an aggressive neoplasm. Other neoplastic and non-neoplastic conditions that may involve the corpus callosum and mimic a butterfly glioma, as well as associated imaging features, are discussed.

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

    PubMed Central

    Corsello, Christina; Kennedy, Daniel P.; Adolphs, Ralph

    2014-01-01

    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

  6. 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

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

    PubMed

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

    2013-01-01

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

  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. The Corpus Callosum and Reading: An MRI Volumetric Study

    ERIC Educational Resources Information Center

    Fine, Jodene Goldenring

    2006-01-01

    Researchers have long been interested in the role of the corpus callosum in reading disorder, but existing studies have yielded inconsistent results. Some have found larger corpus callosa in those with reading disorder, others have found smaller corpus callosa, and some have found no differences in the corpus callosa of persons with and without…

  10. 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.

  11. 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.

  12. Cavernous angioma of the corpus callosum presenting with acute psychosis.

    PubMed

    Pavesi, Giacomo; Causin, Francesco; Feletti, Alberto

    2014-01-01

    Psychiatric symptoms may occasionally be related to anatomic alterations of brain structures. Particularly, corpus callosum lesions seem to play a role in the change of patients' behavior. We present a case of a sudden psychotic attack presumably due to a hemorrhagic cavernous angioma of the corpus callosum, which was surgically removed with complete resolution of symptoms. Although a developmental defect like agenesis or lipoma is present in the majority of these cases, a growing lesion of the corpus callosum can rarely be the primary cause. Since it is potentially possible to cure these patients, clinicians should be aware of this association.

  13. Restricted diffusion in the corpus callosum: A neuroradiological marker in hypoxic–ischemic encephalopathy

    PubMed Central

    Kale, Alok; Joshi, Priscilla; Kelkar, A B

    2016-01-01

    Background: Restricted diffusion within the splenium of the corpus callosum has been described by other authors in various conditions, however, restricted diffusion in the entire corpus callosum or isolated involvement of the splenium, genu, or body has been infrequently reported on magnetic resonance imaging (MRI) in neonatal hypoxic–ischemic encephalopathy. We report a series of cases showing different patterns of involvement. Methods and Materials: Perinatal imaging with MRI including diffusion-weighted imaging was performed in 40 neonates with hypoxic–ischemic encephalopathy, including 11 premature neonates. Sixteen out of 40 patients demonstrated restricted diffusion within the corpus callosum. Out of 16 patients, 9 showed restricted diffusion in the entire corpus callosum, 4 had isolated splenium involvement, 2 had body and splenium signal abnormality, and 1 showed diffusion restriction only in the genu. Conclusions: Changes in the corpus callosum were also associated with more severe clinical presentation of encephalopathy. Restricted diffusion within the corpus callosum in infants with hypoxic–ischemic encephalopathy is often associated with extensive brain injury and appears to be an early neuroradiologic marker of adverse neurologic outcome. PMID:28104944

  14. Corpus Callosum Shape Analysis with Application to Dyslexia

    PubMed Central

    Casanova, Manuel F.; El-Baz, Ayman; Elnakib, Ahmed; Giedd, Jay; Rumsey, Judith M.; Williams, Emily L.; Switala, Andrew E.

    2012-01-01

    Morphometric studies of the corpus callosum suggest its involvement in a number of psychiatric conditions. In the present study we introduce a novel pattern recognition technique that offers a point-by-point shape descriptor of the corpus callosum. The method uses arc lengths of electric field lines in order to avoid discontinuities caused by folding anatomical contours. We tested this technique by comparing the shape of the corpus callosum in a series of dyslexic men (n = 16) and age-matched controls (n = 14). The results indicate a generalized increase in size of the corpus callosum in dyslexia with a concomitant diminution at its rostral and caudal poles. The reported shape analysis and 2D-reconstruction provide information of anatomical importance that would otherwise passed unnoticed when analyzing size information alone. PMID:22545196

  15. 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).

  16. Structural abnormalities of corpus callosum and cortical axonal tracts accompanied by decreased anxiety-like behavior and lowered sociability in spock3- mutant mice.

    PubMed

    Yamamoto, Ayako; Uchiyama, Koji; Nara, Tomoka; Nishimura, Naomichi; Hayasaka, Michiko; Hanaoka, Kazunori; Yamamoto, Tatsuro

    2014-01-01

    Spock3/Testican-3 is a nervous system-expressed heparan sulfate proteoglycan belonging to a subgroup of the BM-40/SPARC/osteonectin family, the role of which in brain development is unclear. Because Spock1, a member of the Spock family, inhibits their attachment to substrates and the neurite outgrowth of cultured neuronal cells, Spock3 is also thought to be similarly involved in the neuronal development. In the present study, we established a Spock3-mutant mouse harboring a deletion extending from the presumptive upstream regulatory region to exon 4 of the Spock3 locus and performed histological and behavioral studies on these mutant mice. In wild-type (WT) mice, all Spock members were clearly expressed during brain development. In adults, intense Spock1 and Spock2 expressions were observed throughout the entire brain; whereas, Spock3 expression was no longer visible except in the thalamic nuclei. Thus, Spock3 expression is mostly confined to the developmental stage of the brain. In adult mutant mice, the cells of all cortical layers were swollen. The corpus callosum was narrowed around the central region along the rostral-caudal axis and many small spaces were observed without myelin sheaths throughout the entire corpus callosum. In addition, the cortical input and output fibers did not form into thick bundled fibers as well as the WT counterparts did. Moreover, a subpopulation of corticospinal axonal fibers penetrated into the dorsal striatum with moderately altered orientations. Consistent with these modifications of brain structures, the mutant mice exhibited decreased anxiety-like behavior and lowered sociability. Together, these results demonstrate that Spock3 plays an important role in the formation or maintenance of major neuronal structures in the brain.

  17. 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…

  18. Agenesis of the Corpus Callosum in Two Sisters

    PubMed Central

    Shapira, Yehuda; Cohen, Tirza

    1973-01-01

    Two sisters are described. They are offspring of Arabic parents who are both first and second cousins, through both sets of grandparents; additionally the father's parents are first cousins. The diagnosis of agenesis of the corpus callosum in the propositae was made by the characteristic picture on the pneumoencephalogram. The clinical symptoms in the two sisters varied considerably. The older sister had shown delayed psychomotor development in infancy, mild mental retardation, and developed seizures at 7 years of age of both the grand mal and akinetic types. Her physical and neurological examination did not show any abnormalities. The EEG was severely abnormal with slow wave activity over the posterior parts of the brain and focal spiking. The younger sister presented at 6 months of age with failure to thrive, generalized hypotonia, but without seizures. Her EEG was within normal limits. This anomaly was probably transmitted by an autosomal recessive gene. The clinical and genetic aspects of this syndrome are discussed. Images PMID:4204338

  19. Interleukin-6, age, and corpus callosum integrity.

    PubMed

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

    2014-01-01

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

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

    PubMed Central

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

    2014-01-01

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

  1. Morphometric changes of the corpus callosum in congenital blindness.

    PubMed

    Tomaiuolo, Francesco; Campana, Serena; Collins, D Louis; Fonov, Vladimir S; Ricciardi, Emiliano; Sartori, Giuseppe; Pietrini, Pietro; Kupers, Ron; Ptito, Maurice

    2014-01-01

    We examined the effects of visual deprivation at birth on the development of the corpus callosum in a large group of congenitally blind individuals. We acquired high-resolution T1-weighted MRI scans in 28 congenitally blind and 28 normal sighted subjects matched for age and gender. There was no overall group effect of visual deprivation on the total surface area of the corpus callosum. However, subdividing the corpus callosum into five subdivisions revealed significant regional changes in its three most posterior parts. Compared to the sighted controls, congenitally blind individuals showed a 12% reduction in the splenium, and a 20% increase in the isthmus and the posterior part of the body. A shape analysis further revealed that the bending angle of the corpus callosum was more convex in congenitally blind compared to the sighted control subjects. The observed morphometric changes in the corpus callosum are in line with the well-described cross-modal functional and structural neuroplastic changes in congenital blindness.

  2. 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…

  3. Proteome dynamics during postnatal mouse corpus callosum development

    PubMed Central

    Son, Alexander I.; Fu, Xiaoqin; Suto, Fumikazu; Liu, Judy S.; Hashimoto-Torii, Kazue; Torii, Masaaki

    2017-01-01

    Formation of cortical connections requires the precise coordination of numerous discrete phases. This is particularly significant with regard to the corpus callosum, whose development undergoes several dynamic stages including the crossing of axon projections, elimination of exuberant projections, and myelination of established tracts. To comprehensively characterize the molecular events in this dynamic process, we set to determine the distinct temporal expression of proteins regulating the formation of the corpus callosum and their respective developmental functions. Mass spectrometry-based proteomic profiling was performed on early postnatal mouse corpus callosi, for which limited evidence has been obtained previously, using stable isotope of labeled amino acids in mammals (SILAM). The analyzed corpus callosi had distinct proteomic profiles depending on age, indicating rapid progression of specific molecular events during this period. The proteomic profiles were then segregated into five separate clusters, each with distinct trajectories relevant to their intended developmental functions. Our analysis both confirms many previously-identified proteins in aspects of corpus callosum development, and identifies new candidates in understudied areas of development including callosal axon refinement. We present a valuable resource for identifying new proteins integral to corpus callosum development that will provide new insights into the development and diseases afflicting this structure. PMID:28349996

  4. Intrahemispheric dysfunction in primary motor cortex without corpus callosum: a transcranial magnetic stimulation study

    PubMed Central

    Fecteau, Shirley; Lassonde, Maryse; Théoret, Hugo

    2006-01-01

    Background The two human cerebral hemispheres are continuously interacting, through excitatory and inhibitory influences and one critical structure subserving this interhemispheric balance is the corpus callosum. Interhemispheric neurophysiological abnormalities and intrahemispheric behavioral impairments have been reported in individuals lacking the corpus callosum. The aim of this study was to examine intrahemispheric neurophysiological function in primary motor cortex devoid of callosal projections. Methods Intracortical excitatory and inhibitory systems were tested in three individuals with complete agenesis of the corpus callosum and sixteen healthy individuals. These systems were assessed using transcranial magnetic stimulation (TMS) protocols: motor threshold at rest, paired-pulse curve, and cortical silent period. Results TMS revealed no difference between the patient and control groups on the motor threshold measure, as well as intracortical facilitation and intracortical inhibition systems as tested by paired stimulation. However, intrahemispheric inhibitory function was found to be abnormal in participants without callosal projections, as the cortical silent period duration was significantly increased in the patient group. Conclusion These data suggest that in addition to previously reported impaired interhemispheric function, patients lacking the entire corpus callosum also display abnormal intrahemispheric excitability of the primary motor cortex. PMID:16790050

  5. 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.

  6. 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

  7. Thick corpus callosum: a clue to the diagnosis of fetal septopreoptic holoprosencephaly?

    PubMed

    Koob, Mériam; Weingertner, Anne-sophie; Gasser, Bernard; Oubel, Estanislao; Dietemann, Jean-Louis

    2012-07-01

    We describe fetal septopreoptic holoprosencephaly (HPE) associated with a thick corpus callosum (CC) diagnosed with MRI in a fetus at 31 weeks' gestation. Our report supports a recently published study connecting a thick fetal CC to other brain abnormalities. On diffusion tensor imaging (DTI), the body of the CC contained an abnormal longitudinal bundle, presumed to be a congenital heterotopic cingulum. Prenatal and postmortem brain MRI with DTI, CT, and pathological analyses are described and illustrated.

  8. 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,…

  9. 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…

  10. 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…

  11. 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 =…

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

    PubMed

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

    2014-01-01

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

  13. 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…

  14. Tractography of the Corpus Callosum in Huntington’s Disease

    PubMed Central

    Phillips, Owen; Sanchez-Castaneda, Cristina; Elifani, Francesca; Maglione, Vittorio; Di Pardo, Alba; Caltagirone, Carlo; Squitieri, Ferdinando; Sabatini, Umberto; Di Paola, Margherita

    2013-01-01

    White matter abnormalities have been shown in presymptomatic and symptomatic Huntington’s disease (HD) subjects using Magnetic Resonance Imaging (MRI) and Diffusion Tensor Imaging (DTI) methods. The largest white matter tract, the corpus callosum (CC), has been shown to be particularly vulnerable; however, little work has been done to investigate the regional specificity of tract abnormalities in the CC. Thus, this study examined the major callosal tracts by applying DTI-based tractography. Using TrackVis, a previously defined region of interest tractography method parcellating CC into seven major tracts based on target region was applied to 30 direction DTI data collected from 100 subjects: presymptomatic HD (Pre-HD) subjects (n = 25), HD patients (n = 25) and healthy control subjects (n = 50). Tractography results showed decreased fractional anisotropy (FA) and increased radial diffusivity (RD) across broad regions of the CC in Pre-HD subjects. Similar though more severe deficits were seen in HD patients. In Pre-HD and HD, callosal FA and RD were correlated with Disease Burden/CAG repeat length as well as motor (UHDRSI) and cognitive (URDRS2) assessments. These results add evidence that CC pathways are compromised prior to disease onset with possible demyelination occurring early in the disease and suggest that CAG repeat length is a contributing factor to connectivity deficits. Furthermore, disruption of these callosal pathways potentially contributes to the disturbances of motor and cognitive processing that characterize HD. PMID:24019913

  15. 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.

  16. 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.

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

    PubMed Central

    Bassuk, Alexander G.; Sherr, Elliott H.

    2016-01-01

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

  18. Emotional Intelligence in Agenesis of the Corpus Callosum.

    PubMed

    Anderson, Luke B; Paul, Lynn K; Brown, Warren S

    2017-01-23

    People with agenesis of the corpus callosum (AgCC) with normal general intelligence have deficits in complex cognitive processing, as well as in social cognition. It is uncertain the extent to which impoverished processing of emotions may contribute to social processing deficiencies. We used the Mayer-Salovey-Caruso Emotional Intelligence Test to clarify the nature of emotional intelligence in 16 adults with AgCC. As hypothesized, persons with AgCC exhibited greater disparities from norms on tests involving more socially complex aspects of emotions. The AgCC group did not differ from norms on the Experiential subscale, but they were significantly below norms on the Strategic subscale. These findings suggest that the corpus callosum is not essential for experiencing and thinking about basic emotions in a "normal" way, but is necessary for more complex processes involving emotions in the context of social interactions.

  19. Prenatal PCB exposure, the corpus callosum, and response inhibition.

    PubMed Central

    Stewart, Paul; Fitzgerald, Susan; Reihman, Jacqueline; Gump, Brooks; Lonky, Edward; Darvill, Thomas; Pagano, Jim; Hauser, Peter

    2003-01-01

    The present study reports the association between prenatal exposure to polychlorinated biphenyls (PCBs), the corpus callosum, and response inhibition in children who are 4.5 years old. Children (n = 189) enrolled in the Oswego study were tested using a continuous performance test. We measured (square millimeters) the splenium of the corpus callosum, a pathway implicated in the regulation of response inhibition, using magnetic resonance imaging. Results indicated a dose-dependent association between cord blood PCBs and errors of commission. Splenium size but not other brain areas predicted errors of commission (r(2) = 0.20), with smaller size associated with more errors of commission. There was an interaction between splenium size and PCB exposure. The smaller the splenium, the larger the association between PCBs and errors of commission. If the association between PCBs and response inhibition is indeed causal, then children with suboptimal development of the splenium are particularly vulnerable to these effects. These data await replication. PMID:14527849

  20. 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

  1. Anatomical-behavioral relationships: corpus callosum morphometry and hemispheric specialization.

    PubMed

    Clarke, J M; Zaidel, E

    1994-10-20

    We obtained midsagittal measures of the corpus callosum in 60 healthy young adults (right-handed and left-handed males and females), and examined whether individual differences in anatomical measures of callosal connectivity are related to behavioral laterality measures in the same subjects. In an attempt to tap functionally-distinct callosal "channels", four behavioral laterality tasks were used that differed in sensory modality (visual, auditory, tactile) and/or level of cognitive processing (sensory versus semantic). In addition, the tasks had both intrahemispheric and interhemispheric conditions. Sex differences were found for measures of the posterior body (i.e. isthmus) of the corpus callosum, which, in turn, interacted with handedness. In contrast, only handedness effects were found for the behavioral laterality measures. Anatomical-behavioral correlations did not disclose relationships between callosal size and performance on task conditions requiring sensory interhemispheric integration or transfer. Instead, the correlational findings are consistent with the view that the corpus callosum participates in such higher order "control" functions as the support of bilateral representation of language, functional interhemispheric inhibition, and the maintenance of hemispheric differences in arousal. This is consistent with the finding that regional callosal size is related to the number of small diameter fibers, which are presumed to interconnect homologous association cortices in the two hemispheres.

  2. Age-Specific Dynamics of Corpus Callosum Development in Children and its Peculiarities in Infantile Cerebral Palsy.

    PubMed

    Krasnoshchekova, E I; Zykin, P A; Tkachenko, L A; Aleksandrov, T A; Sereda, V M; Yalfimov, A N

    2016-10-01

    The age dynamics of corpus callosum development was studied on magnetic resonance images of the brain in children aged 2-11 years without neurological abnormalities and with infantile cerebral palsy. The areas of the total corpus callosum and its segments are compared in the midsagittal images. Analysis is carried out with the use of an original formula: proportion of areas of the anterior (genu, CC2; and anterior part, CC3) and posterior (isthmus, CC6 and splenium, CC7) segments: kCC=(CC2+CC3)×CC6/CC7. The results characterize age-specific dynamics of the corpus callosum development and can be used for differentiation, with high confidence, of the brain of children without neurological abnormalities from the brain patients with infantile cerebral palsy.

  3. 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.

  4. 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.

  5. 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

  6. A case report: corpus callosum dysgenesis, microcephaly, infantile spasm, cleft lip-palate, exophthalmos and psychomotor retardation.

    PubMed

    Tütüncüoglu, S; Ozkinay, F; Genel, F; Uran, N; Ozgür, T

    1996-04-01

    In this report, a case with corpus callosum dysgenesis, infantile spasm, microcephaly, psychomotor retardation, exophthalmos, cleft lip-palate and abnormal EEG findings is presented. His parents are first-degree relatives. We could not fully match the findings of our patient with the criteria of any syndrome published to date.

  7. 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

  8. Bilateral sensorineural deafness, partial agenesis of the corpus callosum, and arachnoid cysts in two sisters.

    PubMed

    Hendriks, Y M; Laan, L A; Vielvoye, G J; van Haeringen, A

    1999-09-10

    We describe two sisters (ages 10 and 3 years, respectively) with a normal development and a combination of congenital sensorineural hearing loss, partial agenesis of the corpus callosum, arachnoid cyst, and hydrocephalus. Neither girl has distinctive physical anomalies. In the oldest girl, there was a hearing loss of 80 dB bilaterally, and the most severe loss on audiogram was seen at 2,000-4,000 Hz. In the youngest girl, there was a hearing loss of 100 dB bilaterally. Above 2,000 Hz no neural reactions were seen. Cerebral magnetic resonance imaging in one girl and computed tomography in the other showed a partial agenesis of the corpus callosum and a cyst in the pineal region, causing an aqueduct stenosis by compression and consequent hydrocephalus. The parents have normal hearing, and brain magnetic resonance imaging showed no abnormalities. They are nonconsanguineous but from the same small village. This is the first report of a combination of congenital sensorineural hearing loss, partial agenesis of the corpus callosum, and an arachnoid cyst. The pattern of inheritance is probably autosomal recessive.

  9. 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.

  10. 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.

  11. 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

  12. 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…

  13. 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.

  14. Effects of citicoline therapy on the network connectivity of the corpus callosum in patients with leukoaraiosis

    PubMed Central

    Feng, Liang; Jiang, Hong; Li, Yunxia; Teng, Fei; He, Yusheng

    2017-01-01

    Abstract This study aimed to investigate the effects of citicoline therapy on the network connectivity of the corpus callosum in patients with leukoaraiosis (LA) by diffusion tension imaging (DTI). A total of 30 LA patients with Fazekas score of 2 to 3 were voluntarily assigned into citicoline group (n = 14) and control group (n = 16). In citicoline group, citicoline was administered at 0.6 g/d for 1 year. In control group, central nervous system drugs should not be used, except for sleeping pills and antidepressants. Interventions for pre-existing diseases should be conducted in both groups. During the periods of citicoline therapy and post-treatment follow-up, cranial magnetic resonance imaging and DTI were routinely performed in these patients, and the genu, body, and splenium of corpus callosum were selected as the regions of interest (ROIs). The fractional anisotropy (FA) and mean diffusivity (MD) of each ROI were determined with PANDA software. On recruitment, there were no significant differences in the general characteristics, blood biochemical results, cognition function, and the FA and MD of the corpus callosum between 2 groups (P > 0.05). After 1-year treatment, the FA of the corpus callosum reduced gradually, but the MD of the corpus callosum tended to increased in both group, although significant differences were not observed. However, the reductions in FA of genu and splenium of corpus callosum in citicoline group were significantly lower than in control group (P < 0.05); the reductions in MD of genu, body, and splenium of corpus callosum in citicoline group were significantly lower than in control group (P < 0.05). In LA patients, the disruption of the network connectivity of the corpus callosum deteriorates over time. Citicoline treatment may delay the reduction in FA of corpus callosum, which might be beneficial for the improvement of network connectivity of the corpus callosum. PMID:28121935

  15. Effects of citicoline therapy on the network connectivity of the corpus callosum in patients with leukoaraiosis.

    PubMed

    Feng, Liang; Jiang, Hong; Li, Yunxia; Teng, Fei; He, Yusheng

    2017-01-01

    This study aimed to investigate the effects of citicoline therapy on the network connectivity of the corpus callosum in patients with leukoaraiosis (LA) by diffusion tension imaging (DTI).A total of 30 LA patients with Fazekas score of 2 to 3 were voluntarily assigned into citicoline group (n = 14) and control group (n = 16). In citicoline group, citicoline was administered at 0.6 g/d for 1 year. In control group, central nervous system drugs should not be used, except for sleeping pills and antidepressants. Interventions for pre-existing diseases should be conducted in both groups. During the periods of citicoline therapy and post-treatment follow-up, cranial magnetic resonance imaging and DTI were routinely performed in these patients, and the genu, body, and splenium of corpus callosum were selected as the regions of interest (ROIs). The fractional anisotropy (FA) and mean diffusivity (MD) of each ROI were determined with PANDA software.On recruitment, there were no significant differences in the general characteristics, blood biochemical results, cognition function, and the FA and MD of the corpus callosum between 2 groups (P > 0.05). After 1-year treatment, the FA of the corpus callosum reduced gradually, but the MD of the corpus callosum tended to increased in both group, although significant differences were not observed. However, the reductions in FA of genu and splenium of corpus callosum in citicoline group were significantly lower than in control group (P < 0.05); the reductions in MD of genu, body, and splenium of corpus callosum in citicoline group were significantly lower than in control group (P < 0.05).In LA patients, the disruption of the network connectivity of the corpus callosum deteriorates over time. Citicoline treatment may delay the reduction in FA of corpus callosum, which might be beneficial for the improvement of network connectivity of the corpus callosum.

  16. 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.

  17. Clinical features of acute corpus callosum infarction patients

    PubMed Central

    Yang, Li-Li; Huang, Yi-Ning; Cui, Zhi-Tang

    2014-01-01

    The clinical manifestation of acute corpus callosum (CC) infarction is lack of specificity and complex, so it is easily missed diagnosis and misdiagnosis in the early stage. The present study aims to describe the clinical features of the acute CC infarction. In this study, 25 patients with corpus callosum infarction confirmed by the brain MRI/DWI and the risk factors were summarized. Patients were classified into genu infarction (3 cases), body infarction (4cases), body and genu infarction (4 cases), body and splenium infarction (1 case), splenium infarction (13 cases) according to lesion location. Clinical manifestation and prognosis were analyzed among groups. The results indicated that CC infarction in patients with high-risk group accounted for 72%, moderate-risk group accounted for 20%, low-risk group (8%). The main risk factors are carotid intimal thickening or plaque formation, hypertension, hyperlipidemia, cerebral artery stenosis, and so on. The CC infarction often merged with other parts infarction, and splenium infarction had the highest incidence, the clinical symptoms in the body infarction which can appear typical signs and symptoms, but in other parts infarction which always merged many nerve defect symptoms. The body infarction prognosis is poor; the rest parts of infarction are more favorable prognosis. In conclusion, CC infarction has the highest incidence in the stroke of high-risk group; neck color Doppler and TCD examination can be found as early as possible to explore the pathogenic factors. Prognosis is usually much better by treatment according to the location and risk factors. PMID:25197390

  18. Morphologic alterations in the corpus callosum in abuse-related posttraumatic stress disorder: a preliminary study.

    PubMed

    Kitayama, Noriyuki; Brummer, Marijn; Hertz, Lois; Quinn, Sinead; Kim, Yoshiharu; Bremner, J Douglas

    2007-12-01

    Magnetic resonance imaging (MRI) studies in children with maltreatment-related posttraumatic stress disorder (PTSD) have demonstrated smaller corpus callosum area, with the greatest magnitude of change in posterior portions of the corpus callosum. The purpose of this study was to measure corpus callosum area in adult female patients with childhood abuse-related PTSD and comparison subjects. MRI was used to measure the midsagittal area of the corpus callosum as well as subregions of the corpus callosum in 9 female subjects with abuse-related PTSD and 9 healthy female subjects. No differences were found in total area of the corpus callosum or in individual subregions, but the subregion/total area ratio was significantly smaller in posterior midbody in PTSD compared with the healthy subjects. These results suggest that relatively smaller areas of the posterior midbody of the corpus callosum are associated with childhood abuse related PTSD in adults; these findings are consistent with findings in children with abuse-related PTSD.

  19. Corpus callosum shape is altered in individuals with nonsyndromic cleft lip and palate.

    PubMed

    Weinberg, Seth M; Parsons, Trish E; Fogel, Melissa R; Walter, Courtney P; Conrad, Amy L; Nopoulos, Peg

    2013-05-01

    Individuals with nonsyndromic cleft lip with or without cleft palate (CL/P) have altered brain structure compared with healthy controls. Preliminary evidence suggests that the corpus callosum may be dysmorphic in orofacial clefting; however, this midline brain structure has not been systematically assessed in this population. The goal of the present study was to carry out a morphometric assessment of the corpus callosum and its relationship to cognitive performance in a well-characterized patient cohort with orofacial cleft. Midline brain images were obtained from previously collected MRI scans of 24 CL/P subjects and 40-adult-male controls. Eight landmarks on the corpus callosum were digitized on each image and their x,y coordinate locations saved. A geometric morphometrics analysis was applied to the landmark coordinate data to test for shape differences across groups. The relationship between corpus callosum shape and IQ was explored with nonparametric correlation coefficients. Results revealed significant differences in mean corpus callosum shape between CL/P cases and controls (P = 0.029). The CL/P corpus callosum was characterized by increased overall convexity resulting from a superior and posterior displacement. Within CL/P cases, increased corpus callosum shape dysmorphology was moderately correlated with reduced performance IQ (r = 0.546). These results provide additional evidence that midline brain changes may be an important part of the orofacial cleft phenotype.

  20. Cross-sectional area of the elephant corpus callosum: comparison to other eutherian mammals.

    PubMed

    Manger, P R; Hemingway, J; Haagensen, M; Gilissen, E

    2010-05-19

    The current study reports our findings of the relationship between cross-sectional area of the corpus callosum and brain mass in over 100 eutherian mammal species. We were specifically interested in determining whether the elephant had a corpus callosum the size that would be expected for eutherian mammal with a brain mass of approximately 5000 g, or whether a different morphology had evolved. To answer this question we first analysed data from primates, other eutherian mammals and cetaceans, finding that primates and other eutherian mammals showed a positive allometric relationship between the two variables, such that larger brains had a relatively larger corpus callosum. Interestingly, primates have a slightly larger corpus callosum than other eutherian mammals, but showed a similar allometric scaling to this group. The cetaceans had a both absolutely and relatively small corpus callosum compared to other mammals and showed isometric scaling with brain mass. The six elephants studied herein had the largest absolute corpus callosums recorded to date; however, relative to the mass of their brain, the size of the corpus callosum was what would be expected of a typical eutherian mammal with a brain mass of approximately 5000 g. The data for elephants hinted at sexual dimorphism in size of the corpus callosum, with female elephants having both an absolute and relatively larger callosum than the males. If this observation is supported in future studies, the elephants will be the first non-primate species to show sexual dimorphism in this neural character. The results are discussed in both an evolutionary and functional context.

  1. The relationship between early life stress and microstructural integrity of the corpus callosum in a non-clinical population

    PubMed Central

    Paul, Robert; Henry, Lorrie; Grieve, Stuart M; Guilmette, Thomas J; Niaura, Raymond; Bryant, Richard; Bruce, Steven; Williams, Leanne M; Richard, Clark C; Cohen, Ronald A; Gordon, Evian

    2008-01-01

    Background Previous studies have examined the impact of early life stress (ELS) on the gross morphometry of brain regions, including the corpus callosum. However, studies have not examined the relationship between ELS and the microstructural integrity of the brain. Methods In the present study we evaluated this relationship in healthy non-clinical participants using diffusion tensor imaging (DTI) and self-reported history of ELS. Results Regression analyses revealed significant reductions in fractional anisotropy (FA) within the genu of the corpus callosum among those exposed to the greatest number of early life stressors, suggesting reduced microstructural integrity associated with increased ELS. These effects were most pronounced in the genu of the corpus callosum compared to the body and splenium, and were evident for females rather than males despite no differences in total ELS exposure between the sexes. In addition, a further comparison of those participants who were exposed to no ELS vs. three or more ELS events revealed lower FA in the genu of the corpus callosum among the ELS-exposed group, with trends of FA reduction in the body and the whole corpus callosum. By contrast, there were no relationships between ELS and volumetric analysis of the CC regions. The two group did not differ significantly on measures of current depression, stress or anxiety. Conclusion Our results reveal that greater exposure to ELS is associated with microstructural alterations in the white matter in the absence of significant volumetric changes. Importantly, our results indicate that exposure to ELS is associated with abnormalities on DTI despite the absence of clinically significant psychiatric symptoms. Future studies are needed to determine whether specific types of ELS are more likely to impact brain structure and function. PMID:18728817

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

    PubMed

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

    2015-01-01

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

  3. Mutations in DCC cause isolated agenesis of the corpus callosum with incomplete penetrance.

    PubMed

    Marsh, Ashley P L; Heron, Delphine; Edwards, Timothy J; Quartier, Angélique; Galea, Charles; Nava, Caroline; Rastetter, Agnès; Moutard, Marie-Laure; Anderson, Vicki; Bitoun, Pierre; Bunt, Jens; Faudet, Anne; Garel, Catherine; Gillies, Greta; Gobius, Ilan; Guegan, Justine; Heide, Solveig; Keren, Boris; Lesne, Fabien; Lukic, Vesna; Mandelstam, Simone A; McGillivray, George; McIlroy, Alissandra; Méneret, Aurélie; Mignot, Cyril; Morcom, Laura R; Odent, Sylvie; Paolino, Annalisa; Pope, Kate; Riant, Florence; Robinson, Gail A; Spencer-Smith, Megan; Srour, Myriam; Stephenson, Sarah E M; Tankard, Rick; Trouillard, Oriane; Welniarz, Quentin; Wood, Amanda; Brice, Alexis; Rouleau, Guy; Attié-Bitach, Tania; Delatycki, Martin B; Mandel, Jean-Louis; Amor, David J; Roze, Emmanuel; Piton, Amélie; Bahlo, Melanie; Billette de Villemeur, Thierry; Sherr, Elliott H; Leventer, Richard J; Richards, Linda J; Lockhart, Paul J; Depienne, Christel

    2017-04-01

    Brain malformations involving the corpus callosum are common in children with developmental disabilities. We identified DCC mutations in four families and five sporadic individuals with isolated agenesis of the corpus callosum (ACC) without intellectual disability. DCC mutations result in variable dominant phenotypes with decreased penetrance, including mirror movements and ACC associated with a favorable developmental prognosis. Possible phenotypic modifiers include the type and location of mutation and the sex of the individual.

  4. Segmentation of corpus callosum using diffusion tensor imaging: validation in patients with glioblastoma

    PubMed Central

    2012-01-01

    Background This paper presents a three-dimensional (3D) method for segmenting corpus callosum in normal subjects and brain cancer patients with glioblastoma. Methods Nineteen patients with histologically confirmed treatment naïve glioblastoma and eleven normal control subjects underwent DTI on a 3T scanner. Based on the information inherent in diffusion tensors, a similarity measure was proposed and used in the proposed algorithm. In this algorithm, diffusion pattern of corpus callosum was used as prior information. Subsequently, corpus callosum was automatically divided into Witelson subdivisions. We simulated the potential rotation of corpus callosum under tumor pressure and studied the reproducibility of the proposed segmentation method in such cases. Results Dice coefficients, estimated to compare automatic and manual segmentation results for Witelson subdivisions, ranged from 94% to 98% for control subjects and from 81% to 95% for tumor patients, illustrating closeness of automatic and manual segmentations. Studying the effect of corpus callosum rotation by different Euler angles showed that although segmentation results were more sensitive to azimuth and elevation than skew, rotations caused by brain tumors do not have major effects on the segmentation results. Conclusions The proposed method and similarity measure segment corpus callosum by propagating a hyper-surface inside the structure (resulting in high sensitivity), without penetrating into neighboring fiber bundles (resulting in high specificity). PMID:22591335

  5. Oligodendrocyte lineage and subventricular zone response to traumatic axonal injury in the corpus callosum.

    PubMed

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

    2013-12-01

    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/CreER(T):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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. Social cognition in individuals with agenesis of the corpus callosum.

    PubMed

    Symington, Scott H; Paul, Lynn K; Symington, Melissa F; Ono, Makoto; Brown, Warren S

    2010-01-01

    Past research has revealed that individuals with agenesis of the corpus callosum (ACC) have deficits in interhemispheric transfer, complex novel problem-solving, and the comprehension of paralinguistic aspects of language. Case studies and family reports also suggest problems in social cognition. The performance of 11 individuals with complete ACC and with normal intelligence was compared to that of 13 IQ- and age-matched controls on three measures of social cognition. Individuals with ACC were indistinguishable from controls on the Happe Theory of Mind Stories and the Adult Faux Pas Test, but performed significantly worse on various portions of the Thames Awareness of Social Inference Test (TASIT) involving interpretations of videotaped social vignettes. Further analysis of the TASIT indicated that individuals with ACC showed deficiency in the recognition of emotion, weakness in understanding paradoxical sarcasm, and particular difficulty interpreting textual versus visual social cues. These results suggest that the tendency for deficient social cognition in individuals with ACC stems from a combination of difficulty integrating information from multiple sources, using paralinguistic cues for emotion, and understanding nonliteral speech. Together, these deficits would contribute to a less robust theory of mind.

  11. 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

  12. 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.

  13. Acute infarct of the corpus callosum presenting as alien hand syndrome: evidence of diffusion weighted imaging and magnetic resonance angiography

    PubMed Central

    2011-01-01

    Background Infarcts of the corpus callosum are rare and have not been well documented previously. As for a variety of signs and symptoms presented, alien hand syndrome (AHS) can be easily overlooked. Case presentation In this report, we present a patient with a mixed types of AHS coexistence secondary to the corpus callosum infarction, including a motor type of AHS by intermanual conflict (callosal type AHS) and a sensory type of AHS by alien hand and left hemianesthesia (posterior AHS). Conclusions Our case may contribute to the early recognition of AHS and to explore the abnormal neural mechanism of AHS. To our knowledge, rare reports have ever documented such mixed AHS coexisting secondary to the callosal lesion, based on advanced neuroimaging methods as in our case. PMID:22067592

  14. [GENERAL PRINCIPLE OF THE CORPUS CALLOSUM INTERNAL STRUCTURE IN ADULT HUMAN].

    PubMed

    Boiagina, O

    2017-01-01

    The structure of the corpus callosum is a certain form of order of the nerve fibers, glial cells and blood microvessels and it is actually unexplored. We set the goal to understand the general constructive principle of the myeloarchitectonics of human corpus callosum. We used whole mounts of the corpus callosum (5 men and 5 women aged from 36 to 60 years) after their two-week fixation in 10% formalin solution. The next stage was to dissect plate sections of the corpus callosum brainstem in two mutually perpendicular planes. Some of them were subjected to impregnation in 1% osmium tetroxide solution, according to the method adopted in transmission electron microscopy. To prepare these plate sections of the corpus callosum for further study in the light microscope we used the method of plastination in epoxy resin. After complete polymerization plastinated mounts were used for making slices. For further research at high magnification light microscopy they were thinned up to 0.3 mm thickness and were subjected to coloration using 1% solution of methylene blue on 1% borax solution. They were studied using a binocular microscope МБС-9 and microscope "Konus" equipped with digital camera. It was found that the human corpus callosum consists of a number of transversely oriented bands of nerve fibers (commissural cords). Each of them consists of a tightly appressed stratified sections, fascicular rations, which are separated by interstitial layers. In turn, these interfascicular layers give short lateral spurs that divide fascicular rations into individual segments - subfascicular rations. Multiple cells containing interfascicular oligodendrocytes associated with individual subfascicular sets of nerve tracts are dispersed in the cluster order among myelinated nerve fibers of fascicular rations. Fundamentally important point is that the interstitial layers in the corpus callosum as a whole form a complex three-dimensional network structure which is subordinated to the

  15. 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.

  16. Comprehension of humor in primary agenesis of the corpus callosum.

    PubMed

    Brown, Warren S; Paul, Lynn K; Symington, Melissa; Dietrich, Rosalind

    2005-01-01

    Individuals with agenesis of the corpus callosum (ACC) can, in some cases, perform normally on standardized intelligence tests. Nevertheless, recent studies suggest that individuals with ACC and normal IQ scores have deficits in domains of fluid and social intelligence. Anecdotal reports from families suggest diminished appreciation of the subtleties of social interactions, and deficits in the comprehension of jokes and stories. In this research, both the cartoon and narrative joke subtests of a humor test (developed by Brownell et al. [Brownell, H., Michel, D., Powelson, J., & Gardner, H. (1983). Surprise but not coherence: sensitivity to verbal humor in right-hemisphere patients. Brain and language, 18(1), 20-27] and Bihrle et al. [Bihrle, A. M., Brownell, H. H., Powelson, J. A., & Gardner, H. (1986). Comprehension of humorous and non-humorous materials by left and right brain-damaged patients. Brain and Cognition, 5(4), 399-411]) were given to 16 adults with complete ACC (all with IQs>80) and 31 controls of similar age and IQ. Individuals with ACC performed worse than controls on the narrative joke subtest (p<.025) when VIQ was controlled. However, on the cartoon subtest the two groups were not significantly different. Covarying age, forms of IQ, narrative memory, set-switching, and literal language comprehension did not substantially alter the group difference. However, covarying comprehension of nonliteral language and proverbs eliminated the difference, suggesting a common origin for the comprehension of jokes, nonliteral language, and proverbs, most likely related to capacity for understanding second-order meanings.

  17. The combination of thermal dysregulation and agenesis of corpus callosum: Shapiro's or/and reverse Shapiro's syndrome

    PubMed Central

    Topcu, Yasemin; Bayram, Erhan; Karaoglu, Pakize; Yis, Uluc; Kurul, Semra Hiz

    2013-01-01

    Shapiro syndrome is an extremely rare condition consisting the clinical triad of recurrent hypothermia, hyperhydrosis and agenesis of the corpus callosum. On the other hand, reverse Shapiro's sydrome is characterized periodic hyperthermia and agenesis of the corpus callosum. Here, we describe a 3.5-year-old girl with complete agenesis of corpus callosum presenting with recurrent fever and vomiting. She also had hypothermia attacks with accompanying diaphoresis. To the best of our knowledge, there is no described case with episodes of hyperthermia, hypothermia, and vomiting associated with agenesis of the corpus callosum. Recurrent vomiting may be a newly defined symptom associated with these syndromes. PMID:24339619

  18. 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.

  19. PEDF is a novel oligodendrogenic morphogen acting on the adult SVZ and corpus callosum.

    PubMed

    Sohn, Jiho; Selvaraj, Vimal; Wakayama, Kouji; Orosco, Lori; Lee, Eunyoung; Crawford, Susan E; Guo, Fuzheng; Lang, Jordan; Horiuchi, Makoto; Zarbalis, Konstantinos; Itoh, Takayuki; Deng, Wenbin; Pleasure, David

    2012-08-29

    Pigment epithelium-derived factor (PEDF) is a serine protease inhibitor (serpin) protein with well established neuroprotective and anti-angiogenic properties. Recent studies have also shown that PEDF enhances renewal of adult subventricular zone (SVZ) neural precursors. In neurosphere cultures prepared from the SVZ of adult mice, we found that addition of recombinant PEDF to the medium enhanced expressions of oligodendroglial lineage markers (NG2 and PDGFrα) and transcription factors (Olig1, Olig2, and Sox10). Similarly, continuous PEDF administration into the lateral ventricles of adult glial fibrillary acidic protein:green fluorescent protein (GFAP:GFP) transgenic mice increased the proportions of GFAP:GFP+ and GFAP:GFP- SVZ neural precursors coexpressing oligodendroglial lineage markers and transcription factors. Notably, PEDF infusion also resulted in an induction of doublecortin- and Sox10 double-positive cells in the adult SVZ. Immunoreactive PEDF receptor was detectable in multiple cell types in both adult SVZ and corpus callosum. Furthermore, PEDF intracerebral infusion enhanced survival and maturation of newly born oligodendroglial progenitor cells in the normal corpus callosum, and accelerated oligodendroglial regeneration in lysolecithin-induced corpus callosum demyelinative lesions. Western blot analysis showed a robust upregulation of endogenous PEDF in the corpus callosum upon lysolecithin-induced demyelination. Our results document previously unrecognized oligodendrotrophic effects of recombinant PEDF on the adult SVZ and corpus callosum, demonstrate induction of endogenous CNS PEDF production following demyelination, and make PEDF a strong candidate for pharmacological intervention in demyelinative diseases.

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

    PubMed

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

    2016-10-01

    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.

  1. 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

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

    PubMed

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

    2014-03-01

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

  3. The Role of Corpus Callosum Development in Functional Connectivity and Cognitive Processing

    PubMed Central

    Findlay, Anne M.; Honma, Susanne; Jeremy, Rita J.; Strominger, Zoe; Bukshpun, Polina; Wakahiro, Mari; Brown, Warren S.; Paul, Lynn K.; Barkovich, A. James; Mukherjee, Pratik; Nagarajan, Srikantan S.; Sherr, Elliott H.

    2012-01-01

    The corpus callosum is hypothesized to play a fundamental role in integrating information and mediating complex behaviors. Here, we demonstrate that lack of normal callosal development can lead to deficits in functional connectivity that are related to impairments in specific cognitive domains. We examined resting-state functional connectivity in individuals with agenesis of the corpus callosum (AgCC) and matched controls using magnetoencephalographic imaging (MEG-I) of coherence in the alpha (8–12 Hz), beta (12–30 Hz) and gamma (30–55 Hz) bands. Global connectivity (GC) was defined as synchronization between a region and the rest of the brain. In AgCC individuals, alpha band GC was significantly reduced in the dorsolateral pre-frontal (DLPFC), posterior parietal (PPC) and parieto-occipital cortices (PO). No significant differences in GC were seen in either the beta or gamma bands. We also explored the hypothesis that, in AgCC, this regional reduction in functional connectivity is explained primarily by a specific reduction in interhemispheric connectivity. However, our data suggest that reduced connectivity in these regions is driven by faulty coupling in both inter- and intrahemispheric connectivity. We also assessed whether the degree of connectivity correlated with behavioral performance, focusing on cognitive measures known to be impaired in AgCC individuals. Neuropsychological measures of verbal processing speed were significantly correlated with resting-state functional connectivity of the left medial and superior temporal lobe in AgCC participants. Connectivity of DLPFC correlated strongly with performance on the Tower of London in the AgCC cohort. These findings indicate that the abnormal callosal development produces salient but selective (alpha band only) resting-state functional connectivity disruptions that correlate with cognitive impairment. Understanding the relationship between impoverished functional connectivity and cognition is a key step

  4. 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.

  5. Right hand predominant constructional apraxia due to right hemisphere infarction without corpus callosum lesions.

    PubMed

    Kobayashi, Zen; Watanabe, Mayumi; Karibe, Yuri; Nakazawa, Chika; Numasawa, Yoshiyuki; Tomimitsu, Hiroyuki; Shintani, Shuzo

    2014-01-01

    A 74-year-old right-handed woman without cognitive impairment suddenly developed nonfluent aphasia. Brain MRI showed acute infarction in the right frontal lobe and insula without involvement of the corpus callosum. A neurological examination demonstrated not only transcortical motor aphasia, but also ideomotor apraxia and right hand predominant constructional apraxia (CA). To date, right hand predominant CA has only been reported in patients with corpus callosum lesions. The right hand predominant CA observed in our patient may be associated with the failure to transfer information on the spatial structure from the right hemisphere to the motor cortex of the left hemisphere.

  6. 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…

  7. Exuberant projection into the corpus callosum from the visual cortex of newborn cats.

    PubMed

    Innocenti, G M; Fiore, L; Caminiti, R

    1977-04-01

    In the first postnatal week, neurones projecting into the corpus callosum can be identified in kitten's visual cortex by retrograde transport of HRP. The neurones are located in layers III, IV, and VI. The region of cortex which gives rise to the callosal projection extends beyond its adult boundaries over most of area 17, 18, 19 and in the suprasylvian sulcus.

  8. Moebius syndrome with Dandy-Walker variant and agenesis of corpus callosum.

    PubMed

    John, Jomol Sara; Vanitha, R

    2013-09-01

    Moebius syndrome is a rare congenital neurological disorder. The most frequent mode of presentation is facial diplegia with bilateral lateral rectus palsy, but there are variations. Here, we report a rare case of Moebius syndrome in a 15-month-old child with unilateral facial palsy, bilateral abducens nerve palsy with Dandy Walker variant, and complete agenesis of corpus callosum.

  9. 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…

  10. Mental State Understanding in Children with Agenesis of the Corpus Callosum

    PubMed Central

    Lábadi, Beatrix; Beke, Anna M.

    2017-01-01

    Impaired social functioning is a well-known outcome of individuals with agenesis of the corpus callosum. Social deficits in nonliteral language comprehension, humor, social reasoning, and recognition of facial expression have all been documented in adults with agenesis of the corpus callosum. In the present study, we examined the emotional and mentalizing deficits that contributing to the social-cognitive development in children with isolated corpus callosum agenesia, including emotion recognition, theory of mind, executive function, working memory, and behavioral impairments as assessed by the parents. The study involved children between the age of 6 and 8 years along with typically developing children who were matched by IQ, age, gender, education, and caregiver's education. The findings indicated that children with agenesis of the corpus callosum exhibited mild impairments in all social factors (recognizing emotions, understanding theory of mind), and showed more behavioral problems than control children. Taken together, these findings suggest that reduced callosal connectivity may contribute to the development of higher-order social-cognitive deficits, involving limits of complex and rapidly occurring social information to be processed. The studies of AgCC shed lights of the role of structural connectivity across the hemispheres in neurodevelopmental disorders. PMID:28220087

  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. 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…

  13. 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…

  14. Mental State Understanding in Children with Agenesis of the Corpus Callosum.

    PubMed

    Lábadi, Beatrix; Beke, Anna M

    2017-01-01

    Impaired social functioning is a well-known outcome of individuals with agenesis of the corpus callosum. Social deficits in nonliteral language comprehension, humor, social reasoning, and recognition of facial expression have all been documented in adults with agenesis of the corpus callosum. In the present study, we examined the emotional and mentalizing deficits that contributing to the social-cognitive development in children with isolated corpus callosum agenesia, including emotion recognition, theory of mind, executive function, working memory, and behavioral impairments as assessed by the parents. The study involved children between the age of 6 and 8 years along with typically developing children who were matched by IQ, age, gender, education, and caregiver's education. The findings indicated that children with agenesis of the corpus callosum exhibited mild impairments in all social factors (recognizing emotions, understanding theory of mind), and showed more behavioral problems than control children. Taken together, these findings suggest that reduced callosal connectivity may contribute to the development of higher-order social-cognitive deficits, involving limits of complex and rapidly occurring social information to be processed. The studies of AgCC shed lights of the role of structural connectivity across the hemispheres in neurodevelopmental disorders.

  15. 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.

  16. 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.

  17. 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…

  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. 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.

  20. 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…

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

    PubMed Central

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

    2015-01-01

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

  3. 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…

  4. 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.

  5. Magnetic resonance imaging and histological studies of corpus callosal and hippocampal abnormalities linked to doublecortin deficiency.

    PubMed

    Kappeler, Caroline; Dhenain, Marc; Phan Dinh Tuy, Françoise; Saillour, Yoann; Marty, Serge; Fallet-Bianco, Catherine; Souville, Isabelle; Souil, Evelyne; Pinard, Jean-Marc; Meyer, Gundela; Encha-Razavi, Ferechté; Volk, Andreas; Beldjord, Cherif; Chelly, Jamel; Francis, Fiona

    2007-01-10

    Mutated doublecortin (DCX) gives rise to severe abnormalities in human cortical development. Adult Dcx knockout mice show no major neocortical defects but do have a disorganized hippocampus. We report here the developmental basis of these hippocampal abnormalities. A heterotopic band of neurons was identified starting at E17.5 in the CA3 region and progressing throughout the CA1 region by E18.5. At neonatal stages, the CA1 heterotopic band was reduced, but the CA3 band remained unchanged, continuing into adulthood. Thus, in mouse, migration of CA3 neurons is arrested during development, whereas CA1 cell migration is retarded. On the Sv129Pas background, magnetic resonance imaging (MRI) also suggested abnormal dorsal hippocampal morphology, displaced laterally and sometimes rostrally and associated with medial brain structure abnormalities. MRI and cryosectioning showed agenesis of the corpus callosum in Dcx knockout mice on this background and an intermediate, partial agenesis in heterozygote mice. Wild-type littermates showed no callosal abnormalities. Hippocampal and corpus callosal abnormalities were also characterized in DCX-mutated human patients. Severe hippocampal hypoplasia was identified along with variable corpus callosal defects ranging from total agenesis to an abnormally thick or thin callosum. Our data in the mouse, identifying roles for Dcx in hippocampal and corpus callosal development, might suggest intrinsic roles for human DCX in the development of these structures.

  6. 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

  7. Gli3 controls corpus callosum formation by positioning midline guideposts during telencephalic patterning.

    PubMed

    Magnani, Dario; Hasenpusch-Theil, Kerstin; Benadiba, Carine; Yu, Tian; Basson, M Albert; Price, David J; Lebrand, Cécile; Theil, Thomas

    2014-01-01

    The corpus callosum (CC) represents the major forebrain commissure connecting the 2 cerebral hemispheres. Midline crossing of callosal axons is controlled by several glial and neuronal guideposts specifically located along the callosal path, but it remains unknown how these cells acquire their position. Here, we show that the Gli3 hypomorphic mouse mutant Polydactyly Nagoya (Pdn) displays agenesis of the CC and mislocation of the glial and neuronal guidepost cells. Using transplantation experiments, we demonstrate that agenesis of the CC is primarily caused by midline defects. These defects originate during telencephalic patterning and involve an up-regulation of Slit2 expression and altered Fgf and Wnt/β-catenin signaling. Mutations in sprouty1/2 which mimic the changes in these signaling pathways cause a disorganization of midline guideposts and CC agenesis. Moreover, a partial recovery of midline abnormalities in Pdn/Pdn;Slit2(-/-) embryos mutants confirms the functional importance of correct Slit2 expression levels for callosal development. Hence, Gli3 controlled restriction of Fgf and Wnt/β-catenin signaling and of Slit2 expression is crucial for positioning midline guideposts and callosal development.

  8. 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.

  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.

  10. Individual differences in brain asymmetries and fiber composition in the human corpus callosum.

    PubMed

    Aboitiz, F; Scheibel, A B; Fisher, R S; Zaidel, E

    1992-12-11

    There have been several recent reports concerning individual differences in the gross morphometry of the human corpus callosum. However, no studies exist on individual differences in the fiber composition of the corpus callosum. Here we report for the first time the relation of fiber composition in specific callosal segments (as seen in light microscopy) to anatomical asymmetries in language-gifted cortex, as a function of sex. We found a significant negative correlation between Sylvian fissure asymmetries and the total numbers of fibers in the isthmus of males, and in the anterior splenium of females. In addition, a population of relatively large fibers (between 1 micron and 3 microns in diameter) in the isthmus showed a strong negative correlation with perisylvian asymmetries only in males. These findings suggest a sex-dependent, pathway-specific decrease in interhemispheric connectivity with increasing lateralization.

  11. 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.

  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. Germinoma with an extensive rhabdoid cell component centered at the corpus callosum.

    PubMed

    Tajima, Shogo; Koda, Kenji

    2017-03-01

    Intracranial germinomas comprise 0.5-2.0 % of all central nervous system (CNS) tumors and 50-60 % of CNS germ cell tumors. They most frequently originate in the pineal gland and the suprasellar region. The corpus callosum is an extremely uncommon location for germinoma formation. Herein, we report about a 20-year-old man with a germinoma centered at the corpus callosum and that extended to both cerebral hemispheres. In addition to its location, this case is unique in that the amount of tumor cells with rhabdoid morphology exceeded that of tumor cells with typical morphology. The rhabdoid cell component showed an immunophenotype compatible with germinoma. While the presence of rhabdoid cells is generally regarded as a sign of aggressive behavior, the patient has been doing well for at least 4 years since undergoing radiation therapy and chemotherapy. The cellular composition of germinoma might not critically affect prognosis with adequate treatment.

  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. Rare combination of gelastic epilepsy, agenesis of the corpus callosum, and hamartoma.

    PubMed

    Chen, Chia-Chun; Lin, Yu-Ting; Chang, Wen-Cheng; Hsieh, Li-Chun; Liang, Jao-Shwann

    2011-10-01

    Gelastic seizures are rare and are associated with different conditions, but mainly with hypothalamic hamartoma. We report on a boy who presented with mental retardation, aggressive behavior, and generalized tonic-clonic and gelastic seizures. Cranial imaging studies revealed a very rare combination of hypothalamic hamartoma and agenesis of the corpus callosum, which was only reported once previously. His seizure activities demonstrated a modest response to anticonvulsants.

  16. CORPUS CALLOSUM AND EXPERIMENTAL STROKE: STUDIES IN CALLOSOTOMIZED RATS AND ACALLOSAL MICE

    PubMed Central

    Jin, Kunlin; Xie, Lin; Sun, Fen; Mao, XiaoOu; Greenberg, David A.

    2011-01-01

    Background and Purpose Interhemispheric inhibition via the corpus callosum has been proposed as an exacerbating factor in outcome from stroke. Methods We measured infarct volume and behavioral outcome following middle cerebral artery occlusion in callosotomized rats and acallosal mice. Results Neither callosotomy in rats nor callosal agenesis in mice improved infarct volume or behavioral outcome after middle cerebral artery occlusion. Conclusions These findings argue against a role for transcallosal projections in exacerbating focal cerebral ischemia. PMID:21737800

  17. 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.

  18. Repeated prenatal corticosteroid administration delays myelination of the corpus callosum in fetal sheep.

    PubMed

    Huang, W L; Harper, C G; Evans, S F; Newnham, J P; Dunlop, S A

    2001-07-01

    Glucocorticoids regulate oligodendrocyte maturation and the myelin biosynthetic pathways. Synthetic glucocorticoids, the corticosteroids have been successfully used in clinical practice as a single course to enhance lung maturation and reduce mortality and morbidity in preterm infants with no long-term neurologic or cognitive side effects. However, a trend has arisen to use repeated courses despite an absence of safety data from clinical trials. We examined the effects of clinically appropriate, maternally administrated, repeated courses of corticosteroids on myelination of the corpus callosum using sheep as a large animal model. The corpus callosum is a major white matter tract that undergoes protracted myelination, underpins higher order cognitive processing and developmental damage to which is associated with, for example, cerebral palsy, mental retardation and attention deficit hyperactivity disorder. Pregnant ewes were given saline or betamethasone (0.5 mg/kg) at 104,111,118 and 124 days gestation, stages equivalent to the third trimester in humans. Lambs were delivered at 145 days (term), perfused and the corpus callosum examined light and electron microscopically. Total axon numbers were unaffected (P>0.05). However, myelination was significantly delayed. Myelinated axons were 5.7% in the experimental group and 9.2% in controls (P<0.05); conversely, unmyelinated axons were 88.3 and 83.7% (P<0.05). Myelinated axon diameter and myelin sheath thickness were also reduced (0.68 vs. 0.94 and 0.11 vs. 0.14 microm, P<0.05). Our data suggest that repeated prenatal corticosteroid administration delays myelination of the corpus callosum and that further safety data are needed to evaluate clinical practice.

  19. 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.

  20. Connectivity and the corpus callosum in autism spectrum conditions: insights from comparison of autism and callosal agenesis.

    PubMed

    Booth, Rhonda; Wallace, Gregory L; Happé, Francesca

    2011-01-01

    Neural models of autism spectrum disorders (ASDs) have moved, in recent years, from a lesion model to a focus on abnormal connectivity. In this chapter, we review this work and summarize findings from our recent research comparing autism and agenesis of the corpus callosum (AgCC). We discuss our findings in the context of the "fractionable triad" account and highlight three main points. First, the social aspects of autism can be found in isolation, not accompanied by the nonsocial features of this disorder, supporting a view of autism as a "compound," rather than "monolithic," condition. Second, many young people with callosal agenesis show theory of mind- and emotion-processing deficits akin to those seen in autism. Diagnostic overshadowing may mean these people do not receive interventions that have proven beneficial in ASD. Last, study of AgCC shows that it is possible, in some cases, to develop good social cognitive skills in the absence of the corpus callosum, presenting a challenge to future connectivity models of autism.

  1. 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

  2. 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

  3. Structural properties of the human corpus callosum: Multimodal assessment and sex differences.

    PubMed

    Björnholm, L; Nikkinen, J; Kiviniemi, V; Nordström, T; Niemelä, S; Drakesmith, M; Evans, J C; Pike, G B; Veijola, J; Paus, T

    2017-02-22

    A number of structural properties of white matter can be assessed in vivo using multimodal magnetic resonance imaging (MRI). We measured profiles of R1 and R2 relaxation rates, myelin water fraction (MWF) and diffusion tensor measures (fractional anisotropy [FA], mean diffusivity [MD]) across the mid-sagittal section of the corpus callosum in two samples of young individuals. In Part 1, we compared histology-derived axon diameter (Aboitiz et al., 1992) to MRI measures obtained in 402 young men (19.55 ± 0.84 years) recruited from the Avon Longitudinal Study on Parents and Children. In Part 2, we examined sex differences in FA, MD and magnetization transfer ratio (MTR) across the corpus callosum in 433 young (26.50 ± 0.51 years) men and women recruited from the Northern Finland Birth Cohort 1986. We found that R1, R2, and MWF follow the anterior-to-posterior profile of small-axon density. Sex differences in mean MTR were similar across the corpus callosum (males > females) while these in FA differed by the callosal segment (Body: M>F; Splenium: F>M). We suggest that the values of R1, R2 and MWF are driven by high surface area of myelin in regions with high density of "small axons".

  4. 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.

  5. 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.

  6. 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.

  7. Shape-based normalization of the corpus callosum for DTI connectivity analysis.

    PubMed

    Sun, Hui; Yushkevich, Paul A; Zhang, Hui; Cook, Philip A; Duda, Jeffrey T; Simon, Tony J; Gee, James C

    2007-09-01

    The continuous medial representation (cm-rep) is an approach that makes it possible to model, normalize, and analyze anatomical structures on the basis of medial geometry. Having recently presented a partial differential equation (PDE)-based approach for 3-D cm-rep modeling [1], here we present an equivalent 2-D approach that involves solving an ordinary differential equation. This paper derives a closed form solution of this equation and shows how Pythagorean hodograph curves can be used to express the solution as a piecewise polynomial function, allowing efficient and robust medial modeling. The utility of the approach in medical image analysis is demonstrated by applying it to the problem of shape-based normalization of the midsagittal section of the corpus callosum. Using diffusion tensor tractography, we show that shape-based normalization aligns subregions of the corpus callosum, defined by connectivity, more accurately than normalization based on volumetric registration. Furthermore, shape-based normalization helps increase the statistical power of group analysis in an experiment where features derived from diffusion tensor tractography are compared between two cohorts. These results suggest that cm-rep is an appropriate tool for normalizing the corpus callosum in white matter studies.

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

    PubMed Central

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

    2014-01-01

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

  9. Selective increase in posterior corpus callosum thickness between the age of 4 and 11years.

    PubMed

    Westerhausen, René; Fjell, Anders M; Krogsrud, Stine K; Rohani, Darius A; Skranes, Jon S; Håberg, Asta K; Walhovd, Kristine B

    2016-06-07

    Establishing an efficient functional and structural connectivity between the two cerebral hemispheres is an important developmental task during childhood, and alterations in this development have accordingly been linked to a series of neurodevelopmental and pediatric disorders. The corpus callosum, the major white-matter structure connecting the hemispheres, has been shown to increase in size throughout the three first decades of life. However, behavioral studies indicate that adult-like performance levels of functional hemispheric interaction are already reached during middle and late childhood. Thus, here we specifically examine the structural development of the corpus callosum during the functionally relevant time period by for the first time (a) selectively addressing prospective childhood development and (b) analyzing a sample in which also younger children are well represented. Corpus callosum anatomy was assessed from 732 T1-weighted MRI datasets acquired from 428 children (213 boys, 215 girls) aged of 4.1 and 10.9years, of which 304 were scanned at two time points. Regional callosal thickness was determined from an outline-based segmentation of the mid-sagittal cross-sectional surface area. Linear-mixed model analyses revealed a significant increase in thickness with age (effect size: up to 15% explained variance) equivalent to a growth in callosal thickness of up to 0.19mm per year in the posterior corpus callosum. The age effect was found to be stronger in posterior segments (i.e., splenium) than in other callosal subregions. Also, the age effect was found to be comparable between boys and girls, and was detected irrespective of whether developmental or individual differences in overall brain size where accounted for or not. Our results demonstrate a selective increase in posterior corpus-callosum thickness during middle and late childhood. Since axons crossing the midline in the splenium mainly connect occipital and parietal cortices, the accentuated

  10. 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

  11. Clinical utility of corpus callosum measurements in head sonograms of preterm infants: a cohort study

    PubMed Central

    Perenyi, Agnes; Amodio, John; Katz, Joanne S; Stefanov, Dimitre G

    2013-01-01

    Objective To assess the clinical usefulness of measurement of corpus callosum (CC) size in head ultrasound (HUS) to predict short-term neurodevelopmental (ND) outcomes in preterm infants. We hypothesised that including CC measurements in routine HUS will be an additional tool for early identification of infants at risk of adverse short-term ND outcome, over and above the predictive power of perinatal morbidities. Design Retrospective cohort study. Setting Level III neonatal intensive care unit (NICU) and outpatient NICU follow-up clinic of an academic medical centre in New York City. Participants 929 HUS of 502 infants with gestational age of 23–36 weeks in African-American infants were initially studied. Exclusion criteria included those who died, had gross abnormalities in HUS, infants with race other than African-American, infants with suboptimal quality of HUS, late preterm infants and infants who did not participate in ND follow-up. A total of 173 infants completed the study. Interventions CC size (length and thickness) was measured in a subset of 87 infants who had routine HUS between 23 and 29 weeks (0–6 postnatal weeks). Relevant clinical variables were collected from chart reviews. ND assessments were completed in outpatient follow-up clinics. A statistical model was developed to assess the clinical utility and possible predictive value of CC measurements for adverse short-term ND outcome, while adjusting for perinatal morbidities. Primary and secondary outcome measures CC size and ND status. Results Measurements of CC size did not add substantial predictive power to predict short-term ND outcome beyond the information provided by the presence of morbidities related to prematurity. Conclusions No association was found between morbidities related to prematurity and short-term ND outcome and CC size in preterm infants. CC measurements in HUS early in life did not have an additional value in predicting short-term ND outcome, therefore did not seem to

  12. Corpus callosum atrophy is associated with mental slowing and executive deficits in subjects with age‐related white matter hyperintensities: the LADIS Study

    PubMed Central

    Jokinen, Hanna; Ryberg, Charlotte; Kalska, Hely; Ylikoski, Raija; Rostrup, Egill; Stegmann, Mikkel B; Waldemar, Gunhild; Madureira, Sofia; Ferro, José M; van Straaten, Elizabeth C W; Scheltens, Philip; Barkhof, Frederik; Fazekas, Franz; Schmidt, Reinhold; Carlucci, Giovanna; Pantoni, Leonardo; Inzitari, Domenico; Erkinjuntti, Timo

    2007-01-01

    Background Previous research has indicated that corpus callosum atrophy is associated with global cognitive decline in neurodegenerative diseases, but few studies have investigated specific cognitive functions. Objective To investigate the role of regional corpus callosum atrophy in mental speed, attention and executive functions in subjects with age‐related white matter hyperintensities (WMH). Methods In the Leukoaraiosis and Disability Study, 567 subjects with age‐related WMH were examined with a detailed neuropsychological assessment and quantitative magnetic resonance imaging. The relationships of the total corpus callosum area and its subregions with cognitive performance were analysed using multiple linear regression, controlling for volume of WMH and other confounding factors. Results Atrophy of the total corpus callosum area was associated with poor performance in tests assessing speed of mental processing—namely, trail making A and Stroop test parts I and II. Anterior, but not posterior, corpus callosum atrophy was associated with deficits of attention and executive functions as reflected by the symbol digit modalities and digit cancellation tests, as well as by the subtraction scores in the trail making and Stroop tests. Furthermore, semantic verbal fluency was related to the total corpus callosum area and the isthmus subregion. Conclusions Corpus callosum atrophy seems to contribute to cognitive decline independently of age, education, coexisting WMH and stroke. Anterior corpus callosum atrophy is related to the frontal‐lobe‐mediated executive functions and attention, whereas overall corpus callosum atrophy is associated with the slowing of processing speed. PMID:17028118

  13. Agenesis of the corpus callosum in Turner's syndrome: report of a case and review of the literature.

    PubMed

    Lee, Ying-Ying; Hung, June; Chang, Ting-Yu; Huang, Chin-Chang

    2008-09-01

    Turner's syndrome (TS) is a genetic disorder caused by loss of entire or a substantial part of the X-chromosome, but association with central nervous system (CNS) abnormalities is rarely reported. A 32-year-old female with TS was found to have agenesis of the corpus callosum (ACC) and various clinical features including coarctation of aorta, hypertelorism, small jaw, short and webbed neck, cubitus valgus, and absence of the uterus. Karyotype analysis revealed X monosomy cell line (45, X). There have been only three other cases of TS associated with ACC. High prenatal lethality of TS fetuses with congenital CNS malformations may decrease the incidence of this association. Neuropsychological studies showed a normal intelligence neither prominent learning disability nor discrepancy between verbal and non-verbal items.

  14. Agenesis of the corpus callosum in ddN strain mouse associated with unusual facial appearance (flat-face).

    PubMed

    Ozaki, H S; Murakami, T H; Toyoshima, T; Shimada, M

    1984-02-01

    In the course of an experiment involving brother-sister matings between ddN strain mice, mice occurred with an unusual facial appearance (flat-face). Subsequently, 4 mice with flat-face were bred from the litters of the second birth (ca. 10% frequency). This flat-face was assumed to be the result of a malformed short nose, hypoplastic maxilla and mandible, and hypertelorism. These 4 flat-face mice exhibited no significant delays in growth, motor ability or the development of learning ability. Histologically, they were all characterized by an almost total absence of callosal fibers and the presence of abnormal longitudinal neuromatous bundles. Therefore, the flat-face mice may be useful as experimental animals for brain research, as one can easily judge that they lack the corpus callosum from the facial appearance.

  15. Enriched environment increases the total number of CNPase positive cells in the corpus callosum of middle-aged rats.

    PubMed

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

    2011-01-01

    It had been reported that enriched environment was beneficial for the brain cognition, neurons and synapses in cortex and hippocampus. With diffusion tensor imaging (DTI), several studies recently found the trained-induced larger corpus callosum. However, the effect of enriched environment on the oligodendrocytes in corpus callosum has not been explored with the unbiased stereological methods. In current study, the effect of enriched environment on the total number of 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) positive cells in middle-aged rat corpus callosum was investigated by means of immunohistochemical techniques and the unbiased stereological methods. We found that, when compared to standard rats, the spatial learning capacity of enriched-environment rats was significantly increased. The total number of the CNPase positive cells in the corpus callosum of enriched-environment middle-aged rats was significantly increased when compared to standard rats. The present study provided, to the best of our knowledge, the first evidence of environmental enrichment-induced increases in the total number of CNPase positive cells in the corpus callosum of middle-aged rats.

  16. The effect of injury timing on white matter changes in the corpus callosum following unilateral brain injury.

    PubMed

    Hawe, Rachel L; Sukal-Moulton, Theresa; Dewald, Julius P A

    2013-01-01

    Motor impairments following unilateral brain injuries may be related to changes in the corpus callosum. The purpose of this study was to determine if the corpus callosum is impacted differently in pediatric versus adult hemiplegia. Diffusion tensor imaging was completed on 41 participants (11 pediatric hemiplegia, 10 adult hemiplegia, 10 pediatric control and 10 adult control). Fractional anisotropy values and cross-sectional areas for five regions of the corpus callosum were compared between subject groups. Additionally, the amount of involuntary activity in the paretic elbow was quantified during non-paretic elbow flexion tasks for a subset of pediatric hemiplegia participants. Fractional anisotropy values were reduced in pediatric hemiplegia compared to pediatric control subjects in callosal regions corresponding to premotor and supplementary motor areas, primary sensory cortex, and parietal, temporal, and occipital cortices. Differences in fractional anisotropy between adult stroke and adult controls were only found in the region corresponding to parietal, temporal, and occipital cortices. Cross-sectional area was affected in all regions of the corpus callosum in pediatric hemiplegia, but only in the primary sensory region in adult hemiplegia. Additionally, changes in the cross-sectional areas were correlated with involuntary mirror movements in the pediatric hemiplegia group. In conclusion, the corpus callosum is affected to a greater extent in pediatric compared to adult hemiplegia, which may explain why unsuppressed mirror movements and difficulty with bimanual coordination are greater problems in this population.

  17. Microglia shape corpus callosum axon tract fasciculation: functional impact of prenatal inflammation.

    PubMed

    Pont-Lezica, Lorena; Beumer, Wouter; Colasse, Sabrina; Drexhage, Hemmo; Versnel, Marjan; Bessis, Alain

    2014-05-01

    Microglia colonise the brain parenchyma at early stages of development and accumulate in specific regions where they participate in cell death, angiogenesis, neurogenesis and synapse elimination. A recurring feature of embryonic microglial is their association with developing axon tracts, which, together with in vitro data, supports the idea of a physiological role for microglia in neurite development. Yet the demonstration of this role of microglia is lacking. Here, we have studied the consequences of microglial dysfunction on the formation of the corpus callosum, the largest commissure of the mammalian brain, which shows consistent microglial accumulation during development. We studied two models of microglial dysfunction: the loss-of-function of DAP12, a key microglial-specific signalling molecule, and a model of maternal inflammation by peritoneal injection of lipopolysaccharide at embryonic day (E)15.5. We also took advantage of the Pu.1(-/-) mouse line, which is devoid of microglia. We performed transcriptional profiling of maternally inflamed and Dap12-mutant microglia at E17.5. The two treatments principally down-regulated genes involved in nervous system development and function, particularly in neurite formation. We then analysed the developmental consequences of these microglial dysfunctions on the formation of the corpus callosum. We show that all three models of altered microglial activity resulted in the defasciculation of dorsal callosal axons. Our study demonstrates that microglia display a neurite-development-promoting function and are genuine actors of corpus callosum development. It further shows that microglial activation impinges on this function, thereby revealing that prenatal inflammation impairs neuronal development through a loss of trophic support.

  18. 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.

  19. 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.

  20. Wnt/Calcium Signaling Mediates Axon Growth and Guidance in the Developing Corpus Callosum

    PubMed Central

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

    2011-01-01

    It has been shown in vivo that Wnt5a gradients surround the corpus callosum and guide callosal axons after the midline (postcrossing) by Wnt5a-induced repulsion via Ryk receptors. In dissociated cortical cultures we showed that Wnt5a simultaneously promotes axon outgrowth and repulsion by calcium signaling. Here to test the role of Wnt5a/calcium signaling in a complex in vivo environment we used sensorimotor cortical slices containing the developing corpus callosum. Plasmids encoding the cytoplasmic marker DsRed and the genetically encoded calcium indicator GCaMP2 were electroporated into one cortical hemisphere. Postcrossing callosal axons grew 50% faster than pre-crossing axons and higher frequencies of calcium transients in axons and growth cones correlated well with outgrowth. Application of pharmacological inhibitors to the slices showed that signaling pathways involving calcium release through IP3 receptors and calcium entry through TRP channels regulate post-crossing axon outgrowth and guidance. Co-electroporation of Ryk siRNA and DsRed revealed that knock down of the Ryk receptor reduced outgrowth rates of postcrossing but not precrossing axons by 50% and caused axon misrouting. Guidance errors in axons with Ryk knockdown resulted from reduced calcium activity. In the corpus callosum CaMKII inhibition reduced the outgrowth rate of postcrossing (but not precrossing) axons and caused severe guidance errors which resulted from reduced CaMKII-dependent repulsion downstream of Wnt/calcium. We show for the first time that Wnt/Ryk calcium signaling mechanisms regulating axon outgrowth and repulsion in cortical cultures are also essential for the proper growth and guidance of postcrossing callosal axons which involve axon repulsion through CaMKII. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 71: 269–283, 2011. PMID:20936661

  1. Agenesis of the corpus callosum in a child with Leber's congenital amaurosis.

    PubMed

    Kiratli, H; Tatlipinar, S

    1999-09-01

    A 2.5-year-old male infant with agenesis of the corpus callosum and Leber's congenital amaurosis is described. The infant had nystagmus as the presenting sign. The fundi showed circumscribed macular atrophy with encircling retinal pigment epithelial hyperplasia (macular coloboma-like lesions), attenuation of the retinal arterioles, and very fine pigment dusting in the peripheral retina. Photopic and scotopic ERG were extinguished. Even though this is an exceedingly rare association, these findings along with neurological symptoms should alert the physician to conduct prompt cranial imaging.

  2. 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

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

    PubMed

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

    2012-04-01

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

  4. The corpus callosum in monozygotic twins concordant and discordant for handedness and language dominance.

    PubMed

    Häberling, Isabelle S; Badzakova-Trajkov, Gjurgjica; Corballis, Michael C

    2012-10-01

    We used diffusion tensor imaging to assess callosal morphology in 35 pairs of monozygotic twins, of which 17 pairs were concordant for handedness and 18 pairs were discordant for handedness. Functional hemispheric language dominance was established for each twin member using fMRI, resulting in 26 twin pairs concordant and 9 twin pairs discordant for language dominance. On the basis of genetic models of handedness and language dominance, which assume one "right shift" (RS) gene with two alleles, an RS+ allele biasing toward right-handedness and left cerebral language dominance and an RS- allele leaving both asymmetries to chance, all twins were classified according to their putative genotypes, and the possible effects of the gene on callosal morphology was assessed. Whereas callosal size was under a high genetic control that was independent of handedness and language dominance, twin pairs with a high probability of carrying the putative RS+ allele showed a connectivity pattern characterized by a genetically controlled, low anisotropic diffusion over the whole corpus callosum. In contrast, the high connectivity pattern exhibited by twin pairs more likely to lack the RS+ allele was under significantly less genetic influence. The data suggest that handedness and hemispheric dominance for speech production might be at least partly dependent on genetically controlled processes of axonal pruning in the corpus callosum.

  5. The Corpus Callosum and the Visual Cortex: Plasticity Is a Game for Two

    PubMed Central

    Pietrasanta, Marta; Restani, Laura; Caleo, Matteo

    2012-01-01

    Throughout life, experience shapes and selects the most appropriate brain functional connectivity to adapt to a changing environment. An ideal system to study experience-dependent plasticity is the visual cortex, because visual experience can be easily manipulated. In this paper, we focus on the role of interhemispheric, transcallosal projections in experience-dependent plasticity of the visual cortex. We review data showing that deprivation of sensory experience can modify the morphology of callosal fibres, thus altering the communication between the two hemispheres. More importantly, manipulation of callosal input activity during an early critical period alters developmental maturation of functional properties in visual cortex and modifies its ability to remodel in response to experience. We also discuss recent data in rat visual cortex, demonstrating that the corpus callosum plays a role in binocularity of cortical neurons and is involved in the plastic shift of eye preference that follows a period of monocular eyelid suture (monocular deprivation) in early age. Thus, experience can modify the fine connectivity of the corpus callosum, and callosal connections represent a major pathway through which experience can mediate functional maturation and plastic rearrangements in the visual cortex. PMID:22792494

  6. 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.

  7. Structural and Functional Reorganization of the Corpus Callosum between the Age of 6 and 8 Years

    PubMed Central

    Luders, Eileen; Specht, Karsten; Ofte, Sonja H.; Toga, Arthur W.; Thompson, Paul M.; Helland, Turid; Hugdahl, Kenneth

    2011-01-01

    The establishment of an efficient exchange of information between the cerebral hemispheres is of crucial importance in the developing functionally lateralized brain. The corpus callosum, the major connection between the cerebral hemispheres, grows constantly throughout childhood and adolescence. However, behavioral studies suggest the existence of a critical time period for callosal functional development starting around the age of 6 years. In the present longitudinal study, examining a cohort of 20 children at the age of 6 and 8 years, we assessed the relationship between structural and functional callosal development during this time period. The structural development was quantified by calculating the increase in callosal thickness using a shape-based computational analysis of the mid-sagittal corpus callosum as obtained with magnetic resonance imaging. The functional development was assessed with a speech discrimination task based on the dichotic presentation of consonant–vowel syllables. The statistical analysis revealed that children whose callosal isthmus increased in thickness over the course of 2 years showed a decrease in interhemispheric information transfer. However, children exhibiting a decrease in isthmus thickness revealed an increase in information transfer. These results might indicate a refinement process of the callosal connections to optimize the neuronal communication between the developing cerebral hemispheres. PMID:20847151

  8. Polymicrogyria, Large Corpus Callosum and Psychomotor Retardation in Four-Year-Old Girl: Potential Association Based on MR Findings

    PubMed Central

    Budai, Caterina; Moscato, Giulia; Patruno, Francesco; Leonardi, Marco; Maffei, Monica

    2014-01-01

    Summary We describe a child from consanguineous parents presenting mega corpus callosum (MegaCC), polymicrogyria, psychomotor retardation with swallowing difficulties and language impairment perhaps linked to the syndrome of megalencephaly-polymicrogyria-mega corpus callosum (MEG-PMG-MegaCC). Reviewing the literature, we speculate that MegaCC, psychomotor retardation and anomalies in cortical migration are the three pathognomonic features. The presence of additional possibly associated anomalies such as megalencephaly, indicates that the spectrum of linked malformations with this rare syndrome is broad and yet to be defined. PMID:25260206

  9. 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

  10. Aging and the myelinated fibers in prefrontal cortex and corpus callosum of the monkey.

    PubMed

    Peters, Alan; Sethares, Claire

    2002-01-14

    In the rhesus monkey, the myelin sheaths of nerve fibers in area 46 of prefrontal cortex and in splenium of the corpus callosum show age-related alterations in their structure. The alterations are of four basic types. Most common is splitting of the dense line of myelin sheaths to accommodate electron dense cytoplasm derived from the oligodendroglia. Less common are splits of the intraperiod line to form balloons or blisters that appear to contain fluid, the occurrence of sheaths with redundant myelin, and thick sheaths that are almost completely split so that one set of compact lamellae is surrounded by another set. But despite these alterations in the sheaths, few nerve fibers show axonal degeneration. To quantify the frequency of the age-related alterations in myelin, transversely sectioned nerve fibers from the splenium of the corpus callosum and from the vertical bundles of nerve fibers within area 46 were examined in electron photomicrographs. The material was taken from 19 monkeys, ranging between 5 and 35 years of age. It was found that the frequency of alterations in myelin sheaths from both locations correlates significantly with age. In area 46, the age-related alterations also significantly correlate (P < 0.001) with an overall assessment of impairment in cognition, i.e., the cognitive impairment index, displayed by individual monkeys. The correlation is also significant when only the old monkeys are considered as a group. A similar result was obtained previously in our examination of the effects of age on the myelin sheaths of nerve fibers in primary visual cortex (Peters et al. [2000] J Comp Neurol. 419:364-376). However, in the corpus callosum the myelin alterations correlate significantly with only one component of the cognitive impairment index, namely the delayed nonmatching to sample task with a 2-minute delay. It is proposed that age-related myelin alterations are ubiquitous and that the correlations between their frequency and impairments in

  11. 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

    2015-03-04

    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.

  12. [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.

  13. 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…

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

    PubMed Central

    Matute, C; Miledi, R

    1993-01-01

    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. Images Fig. 1 Fig. 5 Fig. 6 Fig. 7 PMID:7682696

  15. Topographical organization of human corpus callosum: an fMRI mapping study.

    PubMed

    Fabri, Mara; Polonara, Gabriele; Mascioli, Giulia; Salvolini, Ugo; Manzoni, Tullio

    2011-01-25

    The concept of a topographical map of the corpus callosum (CC) has emerged from human lesion studies and from 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 data on the cortical representation of tactile, gustatory, and visual sensitivity and of motor activation, obtained in 36 volunteers. Activation foci were consistently detected in discrete CC regions: anterior (taste stimuli), central (motor tasks), central and posterior (tactile stimuli), and splenium (visual stimuli). These findings demonstrate that the functional topography of the CC can be explored with fMRI.

  16. 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

  17. Properties of angiotensin II receptors in glial cells from the adult corpus callosum.

    PubMed Central

    Matute, C; Pulakat, L; Río, C; Valcárcel, C; Miledi, R

    1994-01-01

    The existence and the properties of angiotensin II receptors in the adult bovine and human corpus callosum (CC) were investigated by using Xenopus oocytes and primary glial cell cultures. In oocytes injected with CC mRNA, angiotensin II elicited oscillatory Cl- currents due to activation of the inositol phosphate/Ca(2+)-receptor-channel coupling system. The receptors expressed in oocytes and in CC cultures were pharmacologically similar to the AT1 receptor type as assayed by binding. Northern blot analysis and in situ hybridization studies in sections from CC and in glial cultures revealed that the receptors were molecularly related to the AT1 receptor and that they were present in astrocytes. In these cells, activation of the receptors with angiotensin II increased de novo DNA synthesis, promoted the release of aldosterone, and induced c-Fos expression. These findings indicate that CC astrocytes possess functional AT1 receptors that participate in various physiological processes. Images PMID:8170986

  18. Age effects in identifying and localising dichotic stimuli: a corpus callosum deficit?

    PubMed

    Gootjes, Liselotte; Van Strien, Jan W; Bouma, Anke

    2004-09-01

    In the present study, dichotic listening performance of 31 older adults was compared with performance of 25 younger adults under free and focused attention conditions. In addition to an age-related general decrease in performance, we observed in the focused attention condition increased asymmetry in the elderly group: the decrease of recall performance was stronger for the left ear (LE) then for the right ear (RE), while the increase of localisation errors were greater for the RE than for LE. Identifying and localising digits appear to be different process mediated predominantly by the left and right hemisphere, respectively. Since age-related reduced performance is strongest for the ear ipsilateral to the hemisphere dominant to that particular function, these finding may be ascribed to decline of corpus callosum functioning resulting in decrease interhemispheric interaction rather than to a selective decline of right hemisphere functions.

  19. 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.

  20. Androstenediol Reduces Demyelination-Induced Axonopathy in the Rat Corpus Callosum: Impact on Microglial Polarization

    PubMed Central

    Kalakh, Samah; Mouihate, Abdeslam

    2017-01-01

    Aims: We have previously shown that the neurosteroid androstenediol (ADIOL) promotes remyelination following gliotoxin-induced demyelination. However, the impact of this ADIOL on axonal recovery is not yet known. In the present study, we investigated the impact of ADIOL on axonal integrity following a focal demyelination in the corpus callosum. Methods: A 2 μl solution of either ethidium bromide (EB; 0.04%) or pyrogen-free saline were stereotaxically injected into the corpus callosum of Sprague Dawley rats. Each of these two rat groups was divided into two subgroups and received daily subcutaneous injections of either ADIOL (5 mg/kg) or vehicle. The brains were collected at 2, 7 and 14 days post-stereotaxic injection. Immunofluorescent staining was used to explore the impact of ADIOL on axonal integrity (neurofilament (NF)-M) and microglial activation (ionized calcium binding adapter molecule 1, Iba1). The inducible nitric oxide synthase (iNOS) and arginase-1 (arg-1), two major markers of microglial polarization towards the proinflammatory M1 and the regulatory M2 phenotypes respectively, were monitored using western blot. Results: ADIOL increased the density of NF fibers and decreased the extent of axonal damage in the vicinity of the demyelination lesion. ADIOL-induced decrease in axonal damage was manifested by decreased number of axonal spheroids at both 2 and 7 days post-demyelination insult. This reduced axonopathy was associated with decreased expression of iNOS and enhanced expression of arg-1 during the acute phase. Conclusion: These data strongly suggest that ADIOL reduces demyelination-induced axonal damage, likely by dampening the local inflammatory response in the white matter and shifting microglial polarization towards a reparative mode. PMID:28280460

  1. Local-global interference is modulated by age, sex and anterior corpus callosum size

    PubMed Central

    Müller-Oehring, Eva M.; Schulte, Tilman; Raassi, Carla; Pfefferbaum, Adolf; Sullivan, Edith V.

    2007-01-01

    To identify attentional and neural mechanisms affecting global and local feature extraction, we devised a global-local hierarchical letter paradigm to test the hypothesis that aging reduces functional cerebral lateralization through corpus callosum (CC) degradation. Participants (37 men and women, 26–79 years) performed a task requiring global, local, or global+local attention and underwent structural MRI for CC measurement. Although reaction time (RT) slowed with age, all participants had faster RTs to local than global targets. This local precedence effect together with greater interference from incongruent local information and greater response conflict from local targets each correlated with older age and smaller callosal genu (anterior) areas. These findings support the hypothesis that the CC mediates lateralized local-global processes by inhibition of task-irrelevant information under selective attention conditions. Further, with advancing age smaller genu size leads to less robust inhibition, thereby reducing cerebral lateralization and permitting interference to influence processing. Sex was an additional modifier of interference, in that callosum-interference relationships were evident in women but not in men. Regardless of age, smaller splenium (posterior) areas correlated with less response facilitation from repetition priming of global targets in men, but with greater response facilitation from repetition priming of local targets in women. Our data indicate the following dissociation: Anterior callosal structure was associated with inhibitory processes (i.e., interference from incongruency and response conflict), which are vulnerable to the effects of age and sex, whereas posterior callosal structure was associated with facilitation processes from repetition priming dependent on sex and independent of age. PMID:17335783

  2. 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.

  3. Myelination of the corpus callosum in male and female rats following complex environment housing during adulthood

    PubMed Central

    Markham, Julie A.; Herting, Megan M.; Luszpak, Agatha E.; Juraska, Janice M.; Greenough, William T.

    2009-01-01

    Myelination is an important process in brain development, and delays or abnormalities in this process have been associated with a number of conditions including autism, developmental delay, attention deficit disorder, and schizophrenia. Myelination can be sensitive to developmental experience; however, although the adult brain remains highly plastic, it is unknown whether myelination continues to be sensitive to experience during adulthood. Male and female rats were socially housed until four months of age, at which time they were moved into either a complex or “enriched” environment (EC) or an isolated condition (IC). Although the area of the splenium (posterior 20% of the callosum, which contains axons from visual cortical neurons) increased by about 10% following two months of EC housing, the area occupied by myelinated axons was not influenced by adult housing condition. Instead, it was the area occupied by glial cell processes and unmyelinated axons which significantly increased following EC housing. Neither the size nor the myelin content of the genu (anterior 15% of the callosum) was sensitive to manipulations of adult housing condition, but males had more area occupied by myelinated axons in both callosal regions. Finally, the inability of two months of complex environment housing during adulthood to impact the number of myelinated axons in the splenium was confirmed in a subset of animals using quantitative electron microscopy. We conclude that the sensitivity of myelination to experience is reduced in adulthood relative to development in both sexes. PMID:19596280

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

    PubMed Central

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

    2014-01-01

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

  5. Rapidly progressive dementia due to bilateral internal carotid artery occlusion with infarction of the total length of the corpus callosum.

    PubMed

    Rabinstein, Alejandro A; Romano, Jose G; Forteza, Alejandro M; Koch, Sebastian

    2004-04-01

    The authors report a patient with rapidly progressive cognitive decline due to bilateral internal carotid artery occlusion (ICAO) resulting in multiple pathologically proven cerebral infarctions including the entire length of the corpus callosum. The gradual evolution of the deficits was suggestive of hemodynamic ischemia. Bilateral ICAO should be considered in the differential diagnosis of patients with rapidly cognitive decline. Although ICAO commonly spares the splenium, complete callosal infarction is possible in the presence of bilateral ICAO.

  6. Reduced anterior corpus callosum white matter integrity is related to increased impulsivity and reduced discriminability in cocaine-dependent subjects: diffusion tensor imaging.

    PubMed

    Moeller, Frederick Gerard; Hasan, Khader M; Steinberg, Joel L; Kramer, Larry A; Dougherty, Donald M; Santos, Rafael M; Valdes, Ignacio; Swann, Alan C; Barratt, Ernest S; Narayana, Ponnada A

    2005-03-01

    Brain imaging studies find evidence of prefrontal cortical dysfunction in cocaine-dependent subjects. Similarly, cocaine-dependent subjects have problems with behaviors related to executive function and impulsivity. Since prefrontal cortical axonal tracts cross between hemispheres in the corpus callosum, it is possible that white matter integrity in the corpus callosum could also be diminished in cocaine-dependent subjects. The purpose of this study was to compare corpus callosum white matter integrity as measured by the fractional anisotropy (FA) on diffusion tensor imaging (DTI) between 18 cocaine-dependent subjects and 18 healthy controls. The Barratt Impulsiveness Scale (BIS-11) and a continuous performance test: the Immediate and Delayed Memory Task (IMT/DMT) were also collected. Results of the DTI showed significantly reduced FA in the genu and rostral body of the anterior corpus callosum in cocaine-dependent subjects compared to controls. Cocaine-dependent subjects also had significantly higher BIS-11 scores, greater impulsive (commission) errors, and reduced ability to discriminate target from catch stimuli (discriminability) on the IMT/DMT. Within cocaine dependent subjects there was a significant negative correlation between FA in the anterior corpus callosum and behavioral laboratory measured impulsivity, and there was a positive correlation between FA and discriminability. The finding that reduced integrity of anterior corpus callosum white matter in cocaine users is related to impaired impulse control and reduced ability to discriminate between target and catch stimuli is consistent with prior theories regarding frontal cortical involvement in impaired inhibitory control in cocaine-dependent subjects.

  7. Clinical Characterization, Genetics, and Long-Term Follow-up of a Large Cohort of Patients With Agenesis of the Corpus Callosum.

    PubMed

    Romaniello, Romina; Marelli, Susan; Giorda, Roberto; Bedeschi, Maria F; Bonaglia, Maria C; Arrigoni, Filippo; Triulzi, Fabio; Bassi, Maria T; Borgatti, Renato

    2017-01-01

    To gain a better understanding of the clinical and genetic features associated with agenesis of corpus callosum, we enrolled and characterized 162 patients with complete or partial agenesis of corpus callosum. Clinical and genetic protocols allowed us to categorize patients as syndromic subjects, affected by complex extra-brain malformations, and nonsyndromic subjects without any additional anomalies. We observed slight differences in sex ratio (56% males) and agenesis type (52% complete). Syndromic agenesis of corpus callosum subjects were prevalent (69%). We detected associated cerebral malformations in 48% of patients. Neuromotor impairment, cognitive and language disorders, and epilepsy were frequently present, regardless of the agenesis of corpus callosum subtype. Long-term follow-up allowed us to define additional indicators: syndromic agenesis of corpus callosum plus patients showed the most severe clinical features while isolated complete agenesis of corpus callosum patients had the mildest symptoms, although we observed intellectual disability (64%) and epilepsy (15%) in both categories. We achieved a definitive (clinical and/or genetic) diagnosis in 42% of subjects.

  8. A5 segment aneurysm of the anterior cerebral artery, imbedded into the body of the corpus callosum: A case report

    PubMed Central

    Sharafeddin, Fransua; Hafez, Ahmad; Lehecka, Martin; Raj, Rahul; Colasanti, Roberto; Rafiei, Ahmadreza; Choque, Joham; Jahromi, Behnam R.; Niemelä, Mika; Hernesniemi, Juha

    2017-01-01

    Background: The A5 segment aneurysms of the anterior cerebral artery are rare, approximately 0.5% of all intracranial aneurysms. They are small with a wide base located in the midline, with the domes mostly projecting upward or backward. Case Description: The authors describe a unique case of A5 segment aneurysm, with the dome embedded into the body of the corpus callosum. This 41-year-old female was admitted to the neurology department for possible multiple sclerosis investigation. Computed tomography angiogram (CTA) revealed a 4-mm right-sided pericallosal artery aneurysm, with rare configuration, which was caudally projected, embedded into the body of the corpus callosum. Considering the family history, patient underwent a prophylactic ligation surgery. The postoperative CT and CTA showed no complication and successful occlusion of the aneurysm with no ischemia or hemorrhage in the corpus callosum. Conclusion: To the best of our knowledge, this is the first case of an aneurysm with this configuration. Our rare case of A5 segment aneurysm demonstrates the importance of planning of the surgery, choosing the appropriate approach, and knowing the detailed anatomy of the region, as well as the necessity of microsurgical clipping of small unruptured AdistAs. PMID:28217397

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

    PubMed Central

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

    2014-01-01

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

  10. Contribution of posterior corpus callosum to the interhemispheric transfer of tactile information.

    PubMed

    Fabri, Mara; Del Pesce, Maria; Paggi, Aldo; Polonara, Gabriele; Bartolini, Marco; Salvolini, Ugo; Manzoni, Tullio

    2005-06-01

    Three total and three partial callosotomy patients underwent neuropsychological testing to evaluate interhemispheric transfer of tactile information. Tactile transfer is required to name objects presented to the left hand, to compare objects held in either hand, and to transfer topological information between hands. Tactile Naming, Same-Different Recognition, and Tactile Finger Localization Tests (intra- and intermanual tasks) were administered as specific tools. Results were compared with previous fMRI data from the same subjects and with the performance of a control group (20 age-matched subjects). Total callosotomy patients performed modestly: mean correct responses were 93% and 30% (right and left hand, respectively) in Tactile Naming; 68% in Same-Different Recognition; 84% and 76% (right and left hand stimulation, respectively) in intermanual Tactile Finger Localization, and 100% in the intramanual task. Partial callosotomy patients achieved 93-100% accuracy: all have an intact splenium, and one, and possibly all, also an intact posterior callosal body. Controls scored 99% in Tactile Naming, both hands, and Same-Different Recognition; 100% in intramanual Tactile Finger Localization; and 96% and 95%, with right and left hand stimulation, respectively, in the intermanual task. Differences between the two callosotomy groups were significant, as were those between total callosotomy patients and controls. The partial callosotomy group scored like the control subjects. Neuropsychological data agree with previous functional findings, further demonstrating that interhemispheric tactile transfer requires posterior corpus callosum integrity.

  11. 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

  12. Congenital cataract, microphthalmia, hypoplasia of corpus callosum and hypogenitalism: report and review of Micro syndrome.

    PubMed

    Derbent, Murat; Agras, Pinar Isik; Gedik, Sansal; Oto, Sibel; Alehan, Füsun; Saatçi, Umit

    2004-07-30

    We report on a 7-month-old boy with Micro syndrome who was referred for assessment of mental-motor retardation and reduced vision with cataract. The characteristics of Micro syndrome are mental retardation, microcephaly, congenital cataract, microcornea, microphthalmia, agenesis/hypoplasia of the corpus callosum, and hypogenitalism. The differential diagnosis includes cerebro-oculo-facio-skeletal syndrome (COFS); a syndrome involving cataract, arthrogryposis, microcephaly, and kyphoscoliosis (CAMAK); a syndrome with cataract, microcephaly, failure to thrive, and kyphoscoliosis (CAMFAK); Martsolf syndrome; Neu-Laxova syndrome; Lenz microphthalmia syndrome; and Smith-Lemli-Opitz syndrome. Till date, no renal malformations have been reported in Micro syndrome. Our patient had fusion of the lower poles of the kidneys and his left kidney was ectopic. Ocular findings are the most reliable neonatal diagnostic signs of Micro syndrome. Minör anomalies in Micro syndrome may be subtle and therefore not of significant diagnostic value. Micro syndrome is an autosomal recessive trait. Till date, most reported cases have been in individuals of Muslim origin. In countries with high rates of consanguineous marriage, such as Turkey, it is important that physicians be able to recognize this syndrome. Micro syndrome should be considered in any infant with congenital cataract.

  13. Corpus Callosum and Neglect Syndrome: Clinical Findings After Meningioma Removal and Anatomical Review

    PubMed Central

    Gomes, David; Fonseca, Madalena; Garrotes, Maria; Lima, Maria Rita; Mendonça, Marta; Pereira, Mariana; Lourenço, Miguel; Oliveira, Edson; Lavrador, José Pedro

    2017-01-01

    Two types of neglect are described: hemispatial and motivational neglect syndromes. Neglect syndrome is a neurophysiologic condition characterized by a malfunction in one hemisphere of the brain, resulting in contralateral hemispatial neglect in the absence of sensory loss and the right parietal lobe lesion being the most common anatomical site leading to it. In motivational neglect, the less emotional input is considered from the neglected side where anterior cingulate cortex harbors the most frequent lesions. Nevertheless, there are reports of injuries in the corpus callosum (CC) causing hemispatial neglect syndrome, particularly located in the splenium. It is essential for a neurosurgeon to recognize this clinical syndrome as it can be either a primary manifestation of neurosurgical pathology (tumor, vascular lesion) or as a postoperative iatrogenic clinical finding. The authors report a postoperative hemispatial neglect syndrome after a falcotentorial meningioma removal that recovered 10 months after surgery and performs a clinical, anatomical, and histological review centered in CC as key agent in neglect syndrome. PMID:28149091

  14. Planimetry investigation of the corpus callosum in temporal lobe epilepsy patients

    PubMed Central

    Caglar, Veli; Alp, Selen I.; Demir, Berrin T.; Sener, Umit; Ozen, Oguz A.; Alp, Recep

    2016-01-01

    Objective: To evaluate the effects of temporal lobe epilepsy (TLE) on corpus callosum (CC) morphometry in patients with TLE. Methods: This retrospective study was conducted at the Faculty of Medicine, Tekirdag Namik Kemal University, Tekirdag, Turkey between November 2010 and December 2013. The epileptic syndrome diagnosis was based on International League Against Epilepsy criteria, and this study was conducted on the MRIs of 25 epilepsy patients and 25 control subjects. We classified the patients according to their duration of epilepsy <10 and ≥10 years. The projection area length (PAL) of the CC was also estimated. Total brain volumes (TBV) were measured on CT images. Results: The mean values of TBV for patients with TLE and the control group were not statistically different, but the CC PAL values were statistically different. The mean CC PAL values of under and over 25 years of age in patients with TLE were statistically different. The mean values of TBV of under and over 10 years duration of TLE were small statistically, but the CC PAL values were statistically different. Conclusion: The results indicate a clear influence of TLE on the structure of the CC rather than TBV. PMID:27094525

  15. 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.

  16. The development of the corpus callosum in the healthy human brain.

    PubMed

    Luders, Eileen; Thompson, Paul M; Toga, Arthur W

    2010-08-18

    The corpus callosum changes structurally throughout life, but most dramatically during childhood and adolescence. Even so, existing studies of callosal development tend to use parcellation schemes that may not capture the complex spatial profile of anatomical changes. Thus, more detailed mapping of callosal growth processes is desirable to create a normative reference. This will help to relate and interpret other structural, functional, and behavioral measurements, both from healthy subjects and pediatric patients. We applied computational surface-based mesh-modeling methods to analyze callosal morphology at extremely high spatial resolution. We mapped callosal development and explored sex differences in a large and well matched sample of healthy children and adolescents (n = 190) aged 5-18 years. Except for the rostrum in females, callosal thickness increased across the whole surface, with sex- and region-specific rates of growth, and at times shrinkage. The temporally distinct changes in callosal thickness are likely to be a consequence of varying degrees of axonal myelination, redirection, and pruning. Alternating phases of callosal growth and shrinkage may reflect a permanent adjustment and fine-tuning of fibers connecting homologous cortical areas during childhood and adolescence. Our findings emphasize the importance of taking into account sex differences in future studies, as existing developmental effects might remain disguised (or biased toward the effect of the dominant sex in unbalanced statistical designs) when pooling male and female samples.

  17. Light microscopic identification of immature glial cells in semithin sections of the developing mouse corpus callosum.

    PubMed Central

    Sturrock, R R

    1976-01-01

    Four distinct types of glial cell were recognized in the corpus callosum of young postnatal mice: the early glioblast; the small glioblast; the large glioblast; and the young astrocyte. As well as these, mature microglia could be recognized from birth. In semithin, toluidine blue stained sections early glioblasts had large, fair to moderately stained nuclei, and a thin rim of pale cytoplasm; small glioblasts had small, dark nuclei and a rim of darkly stained cytoplasm; large glioblasts had moderately unevenly stained nuclei and a thin rim of moderately stained cytoplasm; and young astrocytes had fairly small nuclei, moderately stained cytoplasm, and one or more processes, which could usually be seen extending for 5 mum or more from the perikaryon. Differential glial counts using the criteria described above, in conjunction with electron microscopic analysis, suggested that early glioblasts gave rise to small glioblasts and large glioblasts; that small glioblasts gave rise directly to astrocytes, large glioblasts, oligodendrocytes and possibly microglia; that large glioblasts formed oligodendrocytes only, and might be immature light oligodendrocytes; and that part of the microglial population might arise from vascular pericytes. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 PMID:795801

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

    PubMed Central

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

    2015-01-01

    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

  19. Altered microstructure rather than morphology in the corpus callosum after lower limb amputation

    PubMed Central

    Li, Zhichao; Li, Chuanming; Fan, Lingzhong; Jiang, Guangyao; Wu, Jixiang; Jiang, Tianzi; Yin, Xuntao; Wang, Jian

    2017-01-01

    The corpus callosum (CC) has been implicated in the reorganization of the brain following amputation. However, it is unclear which regions of the CC are involved in this process. In this study, we explored the morphometric and microstructural changes in CC subregions in patients with unilateral lower limb amputation. Thirty-eight patients and 38 age- and gender-matched normal controls were included. The CC was divided into five regions, and the area, thickness and diffusion parameters of each region were investigated. While morphometric analysis showed no significant differences between the two groups, amputees showed significant higher values in axial diffusivity, radial diffusivity and mean diffusivity in region II of the CC, which connects the bilateral premotor and supplementary motor areas. In contrast, the mean fractional anisotropy value of the fibers generated by these cortical areas, as measured by tractography, was significantly smaller in amputees. These results demonstrate that the interhemispheric pathways contributing to motor coordination and imagery are reorganized in lower limb amputees. PMID:28303959

  20. 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.

  1. Splenium of Corpus Callosum: Patterns of Interhemispheric Interaction in Children and Adults

    PubMed Central

    Knyazeva, Maria G.

    2013-01-01

    The splenium of the corpus callosum connects the posterior cortices with fibers varying in size from thin late-myelinating axons in the anterior part, predominantly connecting parietal and temporal areas, to thick early-myelinating fibers in the posterior part, linking primary and secondary visual areas. In the adult human brain, the function of the splenium in a given area is defined by the specialization of the area and implemented via excitation and/or suppression of the contralateral homotopic and heterotopic areas at the same or different level of visual hierarchy. These mechanisms are facilitated by interhemispheric synchronization of oscillatory activity, also supported by the splenium. In postnatal ontogenesis, structural MRI reveals a protracted formation of the splenium during the first two decades of human life. In doing so, the slow myelination of the splenium correlates with the formation of interhemispheric excitatory influences in the extrastriate areas and the EEG synchronization, while the gradual increase of inhibitory effects in the striate cortex is linked to the local inhibitory circuitry. Reshaping interactions between interhemispherically distributed networks under various perceptual contexts allows sparsification of responses to superfluous information from the visual environment, leading to a reduction of metabolic and structural redundancy in a child's brain. PMID:23577273

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

    PubMed Central

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

    2015-01-01

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

  3. Biallelic SZT2 Mutations Cause Infantile Encephalopathy with Epilepsy and Dysmorphic Corpus Callosum

    PubMed Central

    Basel-Vanagaite, Lina; Hershkovitz, Tova; Heyman, Eli; Raspall-Chaure, Miquel; Kakar, Naseebullah; Smirin-Yosef, Pola; Vila-Pueyo, Marta; Kornreich, Liora; Thiele, Holger; Bode, Harald; Lagovsky, Irina; Dahary, Dvir; Haviv, Ami; Hubshman, Monika Weisz; Pasmanik-Chor, Metsada; Nürnberg, Peter; Gothelf, Doron; Kubisch, Christian; Shohat, Mordechai; Macaya, Alfons; Borck, Guntram

    2013-01-01

    Epileptic encephalopathies are genetically heterogeneous severe disorders in which epileptic activity contributes to neurological deterioration. We studied two unrelated children presenting with a distinctive early-onset epileptic encephalopathy characterized by refractory epilepsy and absent developmental milestones, as well as thick and short corpus callosum and persistent cavum septum pellucidum on brain MRI. Using whole-exome sequencing, we identified biallelic mutations in seizure threshold 2 (SZT2) in both affected children. The causative mutations include a homozygous nonsense mutation and a nonsense mutation together with an exonic splice-site mutation in a compound-heterozygous state. The latter mutation leads to exon skipping and premature termination of translation, as shown by RT-PCR in blood RNA of the affected boy. Thus, all three mutations are predicted to result in nonsense-mediated mRNA decay and/or premature protein truncation and thereby loss of SZT2 function. Although the molecular role of the peroxisomal protein SZT2 in neuronal excitability and brain development remains to be defined, Szt2 has been shown to influence seizure threshold and epileptogenesis in mice, consistent with our findings in humans. We conclude that mutations in SZT2 cause a severe type of autosomal-recessive infantile encephalopathy with intractable seizures and distinct neuroradiological anomalies. PMID:23932106

  4. Role of corpus callosum integrity in arm function differs based on motor severity after stroke.

    PubMed

    Stewart, Jill Campbell; Dewanjee, Pritha; Tran, George; Quinlan, Erin Burke; Dodakian, Lucy; McKenzie, Alison; See, Jill; Cramer, Steven C

    2017-01-01

    While the corpus callosum (CC) is important to normal sensorimotor function, its role in motor function after stroke is less well understood. This study examined the relationship between structural integrity of the motor and sensory sections of the CC, as reflected by fractional anisotropy (FA), and motor function in individuals with a range of motor impairment level due to stroke. Fifty-five individuals with chronic stroke (Fugl-Meyer motor score range 14 to 61) and 18 healthy controls underwent diffusion tensor imaging and a set of motor behavior tests. Mean FA from the motor and sensory regions of the CC and from corticospinal tract (CST) were extracted and relationships with behavioral measures evaluated. Across all participants, FA in both CC regions was significantly decreased after stroke (p < 0.001) and showed a significant, positive correlation with level of motor function. However, these relationships varied based on degree of motor impairment: in individuals with relatively less motor impairment (Fugl-Meyer motor score > 39), motor status correlated with FA in the CC but not the CST, while in individuals with relatively greater motor impairment (Fugl-Meyer motor score ≤ 39), motor status correlated with FA in the CST but not the CC. The role interhemispheric motor connections play in motor function after stroke may differ based on level of motor impairment. These findings emphasize the heterogeneity of stroke, and suggest that biomarkers and treatment approaches targeting separate subgroups may be warranted.

  5. [Neuropsychological studies of two subjects after the transection of the splenium of the corpus callosum. (Part 2. The auditory recognition by the dichotic listening test) (author's transl)].

    PubMed

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

    1979-10-01

    We made the neuropsychological auditory studies of two right-handed subjects who had undergone the transection of the splenium of the corpus callosum for the pineal operation (the teratoma by the histopathological examination). The transection grades were 2.0 cm and 2.5 cm. The truncus and splenium of the second subject were flat by the compression of the tumor. We examined these subjects by the some audiolocigal methods. 1. Pure tone audiometry. 2. Fixed frequency Békésy audiometry. 3. SISI test (short increment sensitivity index test). 4. Speech audiometry. 5. Distorted speech test (filtered speech test). 6. Binaural fusion test. 7. Dichotic listening test. The tasks used for the dichotic listening test were following. Different digits (one pair, three pairs), different words (from two to four syllables) and different vowels and consonants were presented simultaneously to the two ears by means of a dual-channel tape recorder with stereophonic earphone. The result shows that the first subject (whose section of the spelenium was 2.0 cm) shows a slight but not significant superiority on the right ear to the one pair digits and words (p less than 0.1), and the second subject (whose section of the splenium was 2.5 cm and whose splenium and truncus of the corpus callusum were flatten by the compression of the tumor) shows a significant superiority on the right ear to the one pair digits, words, three pairs digits and vowels (p less than 0.05). But there was no definitive abnormalities at the pure tone audiometry, the fixed frequency Békésy audiometry, SISI test, distorted speech test and binaural fusion test of two cases. The result shows that the commissure fibres of the auditory perception of the speech of two hemispheres connect through from splenium to the truncus of the corpus callosum.

  6. Developmental malformation of the corpus callosum: a review of typical callosal development and examples of developmental disorders with callosal involvement.

    PubMed

    Paul, Lynn K

    2011-03-01

    This review provides an overview of the involvement of the corpus callosum (CC) in a variety of developmental disorders that are currently defined exclusively by genetics, developmental insult, and/or behavior. I begin with a general review of CC development, connectivity, and function, followed by discussion of the research methods typically utilized to study the callosum. The bulk of the review concentrates on specific developmental disorders, beginning with agenesis of the corpus callosum (AgCC)-the only condition diagnosed exclusively by callosal anatomy. This is followed by a review of several genetic disorders that commonly result in social impairments and/or psychopathology similar to AgCC (neurofibromatosis-1, Turner syndrome, 22q11.2 deletion syndrome, Williams yndrome, and fragile X) and two forms of prenatal injury (premature birth, fetal alcohol syndrome) known to impact callosal development. Finally, I examine callosal involvement in several common developmental disorders defined exclusively by behavioral patterns (developmental language delay, dyslexia, attention-deficit hyperactive disorder, autism spectrum disorders, and Tourette syndrome).

  7. The Ciliogenic Transcription Factor RFX3 Regulates Early Midline Distribution of Guidepost Neurons Required for Corpus Callosum Development

    PubMed Central

    Benadiba, Carine; Magnani, Dario; Niquille, Mathieu; Morlé, Laurette; Valloton, Delphine; Nawabi, Homaira; Ait-Lounis, Aouatef; Otsmane, Belkacem; Reith, Walter; Theil, Thomas; Hornung, Jean-Pierre

    2012-01-01

    The corpus callosum (CC) is the major commissure that bridges the cerebral hemispheres. Agenesis of the CC is associated with human ciliopathies, but the origin of this default is unclear. Regulatory Factor X3 (RFX3) is a transcription factor involved in the control of ciliogenesis, and Rfx3–deficient mice show several hallmarks of ciliopathies including left–right asymmetry defects and hydrocephalus. Here we show that Rfx3–deficient mice suffer from CC agenesis associated with a marked disorganisation of guidepost neurons required for axon pathfinding across the midline. Using transplantation assays, we demonstrate that abnormalities of the mutant midline region are primarily responsible for the CC malformation. Conditional genetic inactivation shows that RFX3 is not required in guidepost cells for proper CC formation, but is required before E12.5 for proper patterning of the cortical septal boundary and hence accurate distribution of guidepost neurons at later stages. We observe focused but consistent ectopic expression of Fibroblast growth factor 8 (Fgf8) at the rostro commissural plate associated with a reduced ratio of GLIoma-associated oncogene family zinc finger 3 (GLI3) repressor to activator forms. We demonstrate on brain explant cultures that ectopic FGF8 reproduces the guidepost neuronal defects observed in Rfx3 mutants. This study unravels a crucial role of RFX3 during early brain development by indirectly regulating GLI3 activity, which leads to FGF8 upregulation and ultimately to disturbed distribution of guidepost neurons required for CC morphogenesis. Hence, the RFX3 mutant mouse model brings novel understandings of the mechanisms that underlie CC agenesis in ciliopathies. PMID:22479201

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

    PubMed Central

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

    2015-01-01

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

  9. 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.

  10. 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

  11. Neurons in the corpus callosum of the cat during postnatal development.

    PubMed

    Riederer, Beat M; Berbel, Pere; Innocenti, Giorgio M

    2004-04-01

    The corpus callosum (CC) is a major telencephalic commissure containing mainly cortico-cortical axons and glial cells. We have identified neurons in the CC of the cat and quantified their number at different postnatal ages. An antibody against microtubule-associated protein 2 was used as a marker of neurons. Immunocytochemical double-labelling with neuron-specific enolase or gamma-aminobutyric acid antibodies in the absence of glial fibrillary acidic protein positivity confirmed the neuronal phenotype of these cells. CC neurons were also stained with anti-calbindin and anti-calretinin antibodies, typical for interneurons, and with an anti-neurofilament antibody, which in neocortex detects pyramidal neurons. Together, these findings suggest that the CC contains a mixed population of neuronal types. The quantification was corrected for double counting of adjacent sections and volume changes during CC development. Our data show that CC neurons are numerous early postnatally, and their number decreases with age. At birth, about 570 neurons are found within the CC boundaries and their number drops to about 200 in the adult. The distribution of the neurons within the CC also changes in development. Initially, many neurons are found throughout the CC, while at later ages they become restricted to the boundaries of the CC, and in the adult to the rostrum of the CC close to the septum pellucidum or to the indusium griseum. Although origin and function of transient CC neurons in development and in adulthood remain unknown, they are likely to be interstitial neurons. Some of them have well-developed and differentiated processes and resemble pyramidal cells or interneurons. An axon-guiding function during the early postnatal period can not be excluded.

  12. Neuropeptide Y immunoreactive axons in the corpus callosum of the cat during postnatal development.

    PubMed

    Ding, S L; Elberger, A J

    1994-07-01

    Many immunocytochemical studies have identified different types of neurotransmitters localized in the corpus callosum (CC) axons in the adult mammal. Few studies have looked at the development of different neurochemically identified CC systems. Previous studies on the development of cat CC axons have indicated that a large number of transitory CC axons project to the cortex during early postnatal development. The present study focuses on the development of one neurochemically identified group of CC axons in the cat, labeled with an antibody against neuropeptide Y (NPY), to determine if this group participates in transitory CC axonal growth. Cats at specified ages from birth to adulthood were studied with a routine method of immunocytochemistry for antiserum to NPY. NPY-immunoreactive (ir) CC axons were detected at all stages examined, from newborn to adult; the peak density occurred during postnatal weeks (PNW) 3-4. During PNW 1-2, the density of NPY-ir CC axons increased gradually; some NPY-ir axons at this age had growth cones located within the CC bundle between the cerebral hemispheres. The density of the NPY-ir CC axons decreased gradually during PNW 5-7, and from PNW 8 to maturity only a few NPY-ir CC axons were observed. These results indicate that at least two types of NPY-ir CC axons (i.e., transitory and permanent) exist during development, and that most of these axons are eliminated or only express NPY-ir for a short period during development. The results also indicate that neurochemical subsets of CC axons participate in the extensive transitory growth observed by means of the membrane tracer DiI but they may follow unique developmental timetables.

  13. 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.

  14. 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

  15. Social communication in young children with traumatic brain injury: relations with corpus callosum morphometry.

    PubMed

    Ewing-Cobbs, Linda; Prasad, Mary R; Swank, Paul; Kramer, Larry; Mendez, Donna; Treble, Amery; Payne, Christa; Bachevalier, Jocelyne

    2012-05-01

    The purpose of the present investigation was to characterize the relations of specific social communication behaviors, including joint attention, gestures, and verbalization, with surface area of midsagittal corpus callosum (CC) subregions in children who sustained traumatic brain injury (TBI) before 7 years of age. Participants sustained mild (n=10) or moderate-severe (n=26) noninflicted TBI. The mean age at injury was 33.6 months; mean age at MRI was 44.4 months. The CC was divided into seven subregions. Relative to young children with mild TBI, those with moderate-severe TBI had smaller surface area of the isthmus. A semi-structured sequence of social interactions between the child and an examiner was videotaped and coded for specific social initiation and response behaviors. Social responses were similar across severity groups. Even though the complexity of their language was similar, children with moderate-severe TBI used more gestures than those with mild TBI to initiate social overtures; this may indicate a developmental lag or deficit as the use of gestural communication typically diminishes after age 2. After controlling for age at scan and for total brain volume, the correlation of social interaction response and initiation scores with the midsagittal surface area of the CC regions was examined. For the total group, responding to a social overture using joint attention was significantly and positively correlated with surface area of all regions, except the rostrum. Initiating joint attention was specifically and negatively correlated with surface area of the anterior midbody. Use of gestures to initiate a social interaction correlated significantly and positively with surface area of the anterior and posterior midbody. Social response and initiation behaviors were selectively related to regional callosal surface areas in young children with TBI. Specific brainbehavior relations indicate early regional specialization of anterior and posterior CC for social

  16. N-Methyl-D-Aspartate Receptor-Mediated Axonal Injury in Adult Rat Corpus Callosum

    PubMed Central

    Zhang, Jingdong; Liu, Jianuo; Fox, Howard S.; Xiong, Huangui

    2013-01-01

    Damage to white matter such as corpus callosum (CC) is a pathological characteristic in many brain disorders. Glutamate (Glut) excitotoxicity through AMPA receptors on oligodendrocyte (OL) was previously considered as a mechanism for white matter damage. Recent studies have shown that N-methyl-D-aspartate receptors (NMDARs) are expressed on myelin sheath of neonatal rat OL processes and that activation of these receptors mediated demyelization. Whether NMDARs are expressed in the adult CC and are involved in excitotoxic axonal injury remains to be determined. In this study, we demonstrate the presence of NMDARs in the adult rat CC and their distributions in myelinated nerve fibers and OL somata by means of immunocytochemical staining and Western blot. Incubation of the CC slices with Glut or NMDA induced axonal injury as revealed by analyzing amplitude of CC fiber compound action potentials (CAPs) and input–output response. Both Glut and NMDA decreased the CAP amplitude and input–output responses, suggesting an involvement of NMDARs in Glut- and NMDA-induced axonal injury. The involvement of NMDAR in Glut-induced axonal injury was further assayed by detection of β-amyloid precursor protein (β-APP) in the CC axonal fibers. Treatment of the CC slices with Glut resulted in β-APP accumulation in the CC fibers as detected by Western blot, reflecting an impairment of axonal transport function. This injurious effect of Glut on CC axonal transport was significantly blocked by MK801. Taken together, these results show that NMDARs are expressed in the adult CC and are involved in excitotoxic activity in adult CC slices in vitro. PMID:23161705

  17. 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.

  18. A new locus (SPG47) maps to 1p13.2-1p12 in an Arabic family with complicated autosomal recessive hereditary spastic paraplegia and thin corpus callosum.

    PubMed

    Blumkin, Lubov; Lerman-Sagie, Tally; Lev, Dorit; Yosovich, Keren; Leshinsky-Silver, Esther

    2011-06-15

    The hereditary spastic paraplegias (HSP) are a heterogeneous group of genetic neurodegenerative disorders in which the main feature is progressive spasticity of the lower limbs due to pyramidal tract dysfunction. Clinically HSP are divided into two forms: a pure form that presents with progressive lower limb spasticity and weakness, sensory signs and bladder dysfunction, and a complicated form, associated with more extensive neurological and extra neurological signs as well as pathological findings on brain imaging. The clinical variability observed in HSP is supported by the large underlying genetic heterogeneity. Hereditary spastic paraplegia with thin corpus callosum (HSP-TCC) is a frequent subtype of complicated HSP clinically characterized by a slowly progressive spastic paraparesis with cognitive impairment and thin corpus callosum (TCC). SPG11, the most frequent gene associated with HSP-TCC, encodes spatacsin, a protein of unknown function. We describe two siblings from an Arabic consanguineous family with slowly progressive spastic paraparesis, mental retardation, seizures, thin corpus callosum and periventricular white matter abnormalities. Homozygosity mapping identified a novel single candidate region of 7.3 Mb on chromosome 1p13.2-1p12. The finding of a new locus for AR-HSP-TCC further demonstrates the extensive genetic heterogeneity of this condition.

  19. Low-cost, rapidly-developed, 3D printed in vitro corpus callosum model for mucopolysaccharidosis type I

    PubMed Central

    Tabet, Anthony; Gardner, Matthew; Swanson, Sebastian; Crump, Sydney; McMeekin, Austin; Gong, Diana; Tabet, Rebecca; Hacker, Benjamin; Nestrasil, Igor

    2017-01-01

    The rising prevalence of high throughput screening and the general inability of (1) two dimensional (2D) cell culture and (2) in vitro release studies to predict in vivo neurobiological and pharmacokinetic responses in humans has led to greater interest in more realistic three dimensional (3D) benchtop platforms. Advantages of 3D human cell culture over its 2D analogue, or even animal models, include taking the effects of microgeometry and long-range topological features into consideration. In the era of personalized medicine, it has become increasingly valuable to screen candidate molecules and synergistic therapeutics at a patient-specific level, in particular for diseases that manifest in highly variable ways. The lack of established standards and the relatively arbitrary choice of probing conditions has limited in vitro drug release to a largely qualitative assessment as opposed to a predictive, quantitative measure of pharmacokinetics and pharmacodynamics in tissue. Here we report the methods used in the rapid, low-cost development of a 3D model of a mucopolysaccharidosis type I patient’s corpus callosum, which may be used for cell culture and drug release. The CAD model is developed from in vivo brain MRI tracing of the corpus callosum using open-source software, printed with poly (lactic-acid) on a Makerbot Replicator 5X, UV-sterilized, and coated with poly (lysine) for cellular adhesion. Adaptations of material and 3D printer for expanded applications are also discussed. PMID:28357042

  20. 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.

  1. Polymicrogyria, Large Corpus Callosum and Psychomotor Retardation in Four-Year-Old Girl: Potential Association Based on MR Findings. A Case Report and Literature Review.

    PubMed

    Budai, Caterina; Moscato, Giulia; Patruno, Francesco; Leonardi, Marco; Maffei, Monica

    2014-10-01

    SUMMARY - We describe a child from consanguineous parents presenting mega corpus callosum (MegaCC), polymicrogyria, psychomotor retardation with swallowing difficulties and language impairment perhaps linked to the syndrome of megalencephaly-polymicrogyria-mega corpus callosum (MEG-PMG-MegaCC). Reviewing the literature, we speculate that MegaCC, psychomotor retardation and anomalies in cortical migration are the three pathognomonic features. The presence of additional possibly associated anomalies such as megalencephaly, indicates that the spectrum of linked malformations with this rare syndrome is broad and yet to be defined.

  2. Segmented corpus callosum diffusivity correlates with the Expanded Disability Status Scale score in the early stages of relapsing-remitting multiple sclerosis

    PubMed Central

    de Medeiros Rimkus, Carolina; de Faria Junqueira, Thiago; Callegaro, Dagoberto; Otaduy, Maria Concepción García; da Costa Leite, Claudia

    2013-01-01

    OBJECTIVE: The aim of this study was to characterize the microscopic damage to the corpus callosum in relapsing-remitting multiple sclerosis (RRMS) with diffusion tensor imaging and to investigate the correlation of this damage with disability. The diffusion tensor imaging parameters of fractional anisotropy and mean diffusivity provide information about the integrity of cell membranes, offering two more specific indices, namely the axial and radial diffusivities, which are useful for discriminating axon loss from demyelination. METHOD: Brain magnetic resonance imaging exams of 30 relapsing-remitting multiple sclerosis patients and 30 age- and sex-matched healthy controls were acquired in a 3T scanner. The axial diffusivities, radial diffusivities, fractional anisotropy, and mean diffusivity of five segments of the corpus callosum, correlated to the Expanded Disability Status Scale score, were obtained. RESULTS: All corpus callosum segments showed increased radial diffusivities and mean diffusivity, as well as decreased fractional anisotropy, in the relapsing-remitting multiple sclerosis group. The axial diffusivity was increased in the posterior midbody and splenium. The Expanded Disability Status Scale scores correlated more strongly with axial diffusivities and mean diffusivity, with an isolated correlation with radial diffusivities in the posterior midbody of the corpus callosum. There was no significant correlation with lesion loads. CONCLUSION: Neurological dysfunction in relapsing-remitting multiple sclerosis can be influenced by commissural disconnection, and the diffusion indices of diffusion tensor imaging are potential biomarkers of disability that can be assessed during follow-up. PMID:24037007

  3. Identification of a de novo microdeletion 1q44 in a patient with hypogenesis of the corpus callosum, seizures and microcephaly - A case report.

    PubMed

    Westphal, Dominik S; Andres, Stephanie; Beitzel, Kirsten I; Makowski, Christine; Meitinger, Thomas; Hoefele, Julia

    2017-03-21

    Microdeletion 1q44 on the long arm of chromosome 1 leads to a phenotype that includes microcephaly, seizure, agenesis or hypogenesis of the corpus callosum, polydactyly, congenital heart defects and severe developmental delay along with characteristic facial dysmorphic signs. Until today, the distinct genetic causes for the different symptoms remain unclear. We here report a 1.2Mb de novo microdeletion 1q44 identified by performing a SNP array analysis. The female patient presented with microcephaly, seizure, hypogenesis of corpus callosum, postaxial hexadactyly, an atrial septal defect, a ventricular septal defect, hypertelorism, a long and smooth philtrum, thin vermilion borders, and micrognathia, all common features of microdeletion 1q44. An additionally performed chromosome analysis excluded any chromosomal rearrangements. The deleted region included the genes ZBTB18 as well as HNRNPU amongst others. Both are possibly candidate genes for the dysgenesis of the corpus callosum. AKT3, another candidate gene, was not affected by the deletion in this patient. Thus, the genetic findings in this case report spotlight ZBTB18 and HNRNPU in the genesis of the typical microdeletion 1q44 symptoms, especially concerning the dysgenesis of the corpus callosum, and therefore could help to unveil more of the genetic background of this syndrome.

  4. 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

  5. Binocular Interactions in the Lateral Suprasylvian Visual Area of Strabismic Cats Following Section of the Corpus Callosum.

    PubMed

    Di Stefano, M.; Lepore, F.; Ptito, M.; Bédard, S.; Marzi, C. A.; Guillemot, J. P.

    1991-01-01

    Visually responsive neurons have been recorded in the lateral suprasylvian area (LSA) of cats raised with either a convergent or a divergent strabismus. In contrast to areas 17 and 18, where many studies have documented a profound loss of binocularly activated neurons following early strabismus, in the LSA the majority of cells could still be binocularly driven. Acute or chronic section of the splenium of the corpus callosum reduced but did not abolish binocularity in the LSA. We propose that the widespread callosal connections, the large size of the receptive fields and the peculiar internal circuitry of the LSA all concur in permitting the maintenance of binocular coding in spite of early misalignment of the eyes.

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

    PubMed

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

    2009-10-01

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

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

    PubMed

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

    2015-01-01

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

  8. 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.

  9. [Tachistoscope and dichotic listening test of the subject after the transection of the posterior part of the corpus callosum].

    PubMed

    Watanabe, S; Tasaki, H; Hojo, K; Yoshimura, I; Sato, T; Nakaoka, T; Iwabuchi, T

    1982-06-01

    The authors made neuropsychological studies by the tachistoscope and the dichotic listening test on a subject who had undergone the transection of the posterior part of the corpus callosum. As to the tachistoscopic recognition, stimulus material was composed with the various Japanese letters (Katakana, Hiragana, Kanji), various faces (variations of the eyebrow form and the mouth form) and various slopes of line. Table 1 shows results of the cases (the subject was the present case, subjects 1 and subject 2 were past cases). It was seen that the performance of the subject on Japanese letters tasks showed greater right visual field superiority than the one of subject 1 and subject 2. As to the auditory recognition, the tasks used for the dichotic listening test were the following (Table 2, 3, 4). Different digits (three pairs) of the subject showed greater right ear superiority (right ear: 61.1, left ear 5.9) than the ones of subject 1 and subject 2.

  10. 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

  11. 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.

  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. Sex differences in the relationship between planum temporale asymmetry and corpus callosum morphology in chimpanzees (Pan troglodytes): A combined MRI and DTI analysis.

    PubMed

    Hopkins, William D; Hopkins, Anna M; Misiura, Maria; Latash, Elitaveta M; Mareno, Mary Catherine; Schapiro, Steven J; Phillips, Kimberley A

    2016-12-01

    Increases brain size has been hypothesized to be inversely associated with the expression of behavioral and brain asymmetries within and between species. We tested this hypothesis by analyzing the relation between asymmetries in the planum temporale (PT) and different measures of the corpus callosum (CC) including surface area, streamline count as measured from diffusion tensor imaging, fractional anisotropy values and the ratio in the number of fibers to surface area in a sample of chimpanzees. We found that chimpanzees with larger PT asymmetries in absolute terms had smaller CC surface areas, fewer streamlines and a smaller ratio of fibers to surface area. These results were largely specific to male but not female chimpanzees. Our results partially support the hypothesis that brain asymmetries are linked to variation in corpus callosum morphology, although these associations may be sex-dependent.

  14. Why size matters: differences in brain volume account for apparent sex differences in callosal anatomy: the sexual dimorphism of the corpus callosum.

    PubMed

    Luders, Eileen; Toga, Arthur W; Thompson, Paul M

    2014-01-01

    Numerous studies have demonstrated a sexual dimorphism of the human corpus callosum. However, the question remains if sex differences in brain size, which typically is larger in men than in women, or biological sex per se account for the apparent sex differences in callosal morphology. Comparing callosal dimensions between men and women matched for overall brain size may clarify the true contribution of biological sex, as any observed group difference should indicate pure sex effects. We thus examined callosal morphology in 24 male and 24 female brains carefully matched for overall size. In addition, we selected 24 extremely large male brains and 24 extremely small female brains to explore if observed sex effects might vary depending on the degree to which male and female groups differed in brain size. Using the individual T1-weighted brain images (n=96), we delineated the corpus callosum at midline and applied a well-validated surface-based mesh-modeling approach to compare callosal thickness at 100 equidistant points between groups determined by brain size and sex. The corpus callosum was always thicker in men than in women. However, this callosal sex difference was strongly determined by the cerebral sex difference overall. That is, the larger the discrepancy in brain size between men and women, the more pronounced the sex difference in callosal thickness, with hardly any callosal differences remaining between brain-size matched men and women. Altogether, these findings suggest that individual differences in brain size account for apparent sex differences in the anatomy of the corpus callosum.

  15. Contribution of the corpus callosum to bilateral representation of the trunk midline in the human brain: an fMRI study of callosotomized patients.

    PubMed

    Fabri, M; Polonara, G; Mascioli, G; Paggi, A; Salvolini, U; Manzoni, T

    2006-06-01

    Human brain studies have shown that the cutaneous receptors of trunk regions close to the midline are represented in the first somatosensory cortex (SI) of both hemispheres. The present study aims to establish whether in humans, as in non-human primates, the bilateral representation of the trunk midline in area SI depends on the corpus callosum. Data were obtained from eight callosotomized patients: three with complete callosal resection, one with a partial posterior resection including the splenium and the callosal trunk, and four with partial anterior resections sparing the splenium and in one case also the posterior part of the callosal trunk. The investigation was carried out with functional magnetic resonance imaging. Unilateral tactile stimulation was applied by rubbing ventral trunk regions close to the midline (about 20 x 10 cm in width) with a soft cotton pad (frequency 1 Hz). Cortical activation foci elicited by unilateral stimulation of cutaneous regions adjacent to the midline were detected in the contralateral post-central gyrus (PCG), in a region corresponding to the trunk ventral midline representation zone of area SI, as described in a previous study of intact subjects. In most patients, activation foci were also found in the ipsilateral PCG, again as in subjects with an intact corpus callosum. The data confirm that the skin regions adjacent to the trunk midline are represented bilaterally in SI, and indicate that ipsilateral activation is at least partially independent of the corpus callosum.

  16. [A case of left hemi-facial metamorphopsia induced by infarction of the right side of the splenium of the corpus callosum].

    PubMed

    Saito, Yuki; Matsunaga, Akiko; Yamamura, Osamu; Ikawa, Masamichi; Hamano, Tadanori; Yoneda, Makoto

    2014-01-01

    We describe a patient, 61-year-old left-handed Japanese woman, who presented with left hemi-facial metamorphopsia after infarct that extended from the splenium of the corpus callosum to the major forceps on the right side. Past medical history revealed a right putaminal hemorrhage with amnesic aphasia. She complained that the right side of people's faces, that is, the left side when visualized by her, seemed distorted. When she looked at other people's faces, the right half of the faces looked smaller than the left half, and the eyes, noses, and mouths appeared to be hanging toward the center of their faces. This phenomenon was observed for whomever she visualized. She stated that objects other than the face looked normal. Her visual acuity and visual field were normal. Callosal disconnection syndrome was not presented. Magnetic resonance imaging of the brain on diffusion weighted image revealed a high intensity area that extended from the splenium of the corpus callosum to the major forceps on the right side. Electroencephalography did not show any epileptic discharge. Her visual symptoms improved gradually. The mechanism of hemi-facial metamorphopsia remains obscure. We hypothesized that this patient developed left hemi-facial metamorphopsia because of the disrupted transfer of visual information of the left side of face at the splenium of the corpus callosum and the major forceps, which may be the responsible lesion of hemi-facial metamorphopsia.

  17. Surface-based vertexwise analysis of morphometry and microstructural integrity for white matter tracts in diffusion tensor imaging: With application to the corpus callosum in Alzheimer's disease.

    PubMed

    Tang, Xiaoying; Qin, Yuanyuan; Zhu, Wenzhen; Miller, Michael I

    2017-04-01

    In this article, we present a unified statistical pipeline for analyzing the white matter (WM) tracts morphometry and microstructural integrity, both globally and locally within the same WM tract, from diffusion tensor imaging. Morphometry is quantified globally by the volumetric measurement and locally by the vertexwise surface areas. Meanwhile, microstructural integrity is quantified globally by the mean fractional anisotropy (FA) and trace values within the specific WM tract and locally by the FA and trace values defined at each vertex of its bounding surface. The proposed pipeline consists of four steps: (1) fully automated segmentation of WM tracts in a multi-contrast multi-atlas framework; (2) generation of the smooth surface representations for the WM tracts of interest; (3) common template surface generation on which the localized morphometric and microstructural statistics are defined and a variety of statistical analyses can be conducted; (4) multiple comparison correction to determine the significance of the statistical analysis results. Detailed herein, this pipeline has been applied to the corpus callosum in Alzheimer's disease (AD) with significantly decreased FA values and increased trace values, both globally and locally, being detected in patients with AD when compared to normal aging populations. A subdivision of the corpus callosum in both hemispheres revealed that the AD pathology primarily affects the body and splenium of the corpus callosum. Validation analyses and two multiple comparison correction strategies are provided. Hum Brain Mapp 38:1875-1893, 2017. © 2017 Wiley Periodicals, Inc.

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

    PubMed Central

    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; Shenton, Martha E.

    2015-01-01

    Abstract 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

  19. Osseous oral hyaline ring granuloma mimicking a mandible tumor in a child with congenital agenesis of the corpus callosum

    PubMed Central

    Neves-Silva, Rodrigo; Ferreira-Gomes, Camilla-Borges; Palmier, Natalia; Brum-Corrêa, Marcelo; Paes-Almeida, Oslei; Ajudarte-Lopes, Marcio; Agustin-Vargas, Pablo

    2017-01-01

    Background Hyaline ring granuloma (HRG) of the oral cavity is an uncommon disorder considered to be a foreign-body reaction resulting from implantation of food vegetable particles. Microscopically, it is characterized by the presence of structures of hyaline rings in an inflamed fibrous tissue background, which contains multinucleated giant cells. Material and Methods We present the case of a 4-year-old boy diagnosed with a mandible osseous HRG, which showed clinical and tomographic aspects suggestive of an aggressive bone tumor. Results The patient underwent surgical exploration and histopathologic analysis showed fragments composed predominantly of widespread dense connective tissue with an acute and chronic inflammatory infiltrate containing multinucleated giant cells and scattered areas of eosinophilic material associated with hyaline rings, strongly suggestive of vegetable particles. The eosinophilic material was positive for periodic acid-Schiff (PAS) and resistant to diastase digestion. These features led to diagnosis of osseous HRG. Scanning electron microscopy (SEM) analysis was performed for illustrative purposes and the multiple structures resembling vegetable particles were characterized in more detail. Conclusions Although rare, this case highlights the importance of the clinician’s awareness regarding the existence of an osseous counterpart of HRG. Key words:Agenesis of the corpus callosum, child, hyaline ring granuloma, intraosseous, mandible, pulse granuloma. PMID:28210458

  20. Decreased survival in glioblastomas is specific to contact with the ventricular-subventricular zone, not subgranular zone or corpus callosum.

    PubMed

    Mistry, Akshitkumar M; Dewan, Michael C; White-Dzuro, Gabrielle A; Brinson, Philip R; Weaver, Kyle D; Thompson, Reid C; Ihrie, Rebecca A; Chambless, Lola B

    2017-04-01

    The clinical effect of radiographic contact of glioblastoma (GBM) with neurogenic zones (NZ)-the ventricular-subventricular (VSVZ) and subgranular (SGZ) zones-and the corpus callosum (CC) remains unclear and, in the case of the SGZ, unexplored. We investigated (1) if GBM contact with a NZ correlates with decreased survival; (2) if so, whether this effect is associated with a specific NZ; and (3) if radiographic contact with or invasion of the CC by GBM is associated with decreased survival. We retrospectively identified 207 adult patients who underwent cytoreductive surgery for GBM followed by chemotherapy and/or radiation. Age, preoperative Karnofsky performance status score (KPS), and extent of resection were recorded. Preoperative MRIs were blindly analyzed to calculate tumor volume and assess its contact with VSVZ, SGZ, CC, and cortex. Overall (OS) and progression free (PFS) survivals were calculated and analyzed with multivariate Cox analyses. Among the 207 patients, 111 had GBM contacting VSVZ (VSVZ+GBMs), 23 had SGZ+GBMs, 52 had CC+GBMs, and 164 had cortex+GBMs. VSVZ+, SGZ+, and CC+ GBMs were significantly larger in size relative to their respective non-contacting controls. Multivariate Cox survival analyses revealed GBM contact with the VSVZ, but not SGZ, CC, or cortex, as an independent predictor of lower OS, PFS, and early recurrence. We hypothesize that the VSVZ niche has unique properties that contribute to GBM pathobiology in adults.

  1. 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.

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

    PubMed

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

    2013-01-01

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

  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.

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

    PubMed

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

    2014-10-01

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

  5. 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

  6. Progesterone metabolism in the pineal, brain stem, thalamus and corpus callosum of the female rat.

    PubMed

    Hanukoglu, I; Karavolas, H J; Goy, R W

    1977-04-15

    Specific brain regions, namely, thalamus, tectum, tegmentum, cerebellum, medulla and pineal, from five proestrous rats were incubated for 30 min with [3H]progesterone. After reverse isotopic dilution analysis, the following metabolites were identified in all incubations by purification to constant specific activity, derivative formation and/or gas liquid chromatography trapping: [3H]5alpha-pregnane-3, 20-dione (10-20% of the starting substrate except pineal -- 0.7%), [3H]3alpha-hydroxy-5alpha-pregnan-20-one (1.6-3.8% except for pineal -- 0.5%) and [3H]20alpha-hydroxy-4-pregnen-3-one (0.05-0.11%). Preliminary results from the corpus collosum incubation indicated the presence of the same metabolites. Although some apparent constant specific activities were obtained for 20alpha-hydroxy-5alpha-pregnan-3-one and 5beta-pregnane-3, 20-dione, the low levels of 3H associated with these steroids did not permit a definitive identification. The results indicate the presence of at least delta1-steroid 5alpha-reductase, 3alpha-hydroxysteroid dehydrogenase and 20alpha-hydroxysteroid dehydrogenase activities with progesterone as substrate in the brain regions examined.

  7. Working memory and corpus callosum microstructural integrity after pediatric traumatic brain injury: a diffusion tensor tractography study.

    PubMed

    Treble, Amery; Hasan, Khader M; Iftikhar, Amal; Stuebing, Karla K; Kramer, Larry A; Cox, Charles S; Swank, Paul R; Ewing-Cobbs, Linda

    2013-10-01

    Deficits in working memory (WM) are a common consequence of pediatric traumatic brain injury (TBI) and are believed to contribute to difficulties in a range of cognitive and academic domains. Reduced integrity of the corpus callosum (CC) after TBI may disrupt the connectivity between bilateral frontoparietal neural networks underlying WM. In the present investigation, diffusion tensor imaging (DTI) tractography of eight callosal subregions (CC1-CC8) was examined in relation to measures of verbal and visuospatial WM in 74 children sustaining TBI and 49 typically developing comparison children. Relative to the comparison group, children with TBI demonstrated poorer visuospatial WM, but comparable verbal WM. Microstructure of the CC was significantly compromised in brain-injured children, with lower fractional anisotropy (FA) and higher axial and radial diffusivity metrics in all callosal subregions. In both groups of children, lower FA and/or higher radial diffusivity in callosal subregions connecting anterior and posterior parietal cortical regions predicted poorer verbal WM, whereas higher radial diffusivity in callosal subregions connecting anterior and posterior parietal, as well as temporal, cortical regions predicted poorer visuospatial WM. DTI metrics, especially radial diffusivity, in predictive callosal subregions accounted for significant variance in WM over and above remaining callosal subregions. Reduced microstructural integrity of the CC, particularly in subregions connecting parietal and temporal cortices, may act as a neuropathological mechanism contributing to long-term WM deficits. The future clinical use of neuroanatomical biomarkers may allow for the early identification of children at highest risk for WM deficits and earlier provision of interventions for these children.

  8. A novel tool for the morphometric analysis of corpus callosum: applications to the diagnosis of autism - biomed 2009.

    PubMed

    Vatta, Federica; Mininel, Stefano; Colafati, Stefania G; D'Errico, Luigia; Malena, Saverio; Di Salle, Francesco

    2009-01-01

    Autism is a developmental disorder characterized by social deficits, impaired communication, and restricted and repetitive patterns of behaviour. Emerging theories indicate interregional functional and anatomical brain connectivity as a likely key feature in autism pathophysiology. Corpus callosum (CC) represents a natural target of autism connectivity research, being the expression of interhemispheric communication. In this paper, a novel method for a robust morphometric analysis of CC data is presented. The standard morphometric approach is based on the analysis of the size and shape of the CC midsagittal cross-section. As there are no gross anatomical landmarks that clearly delimit anatomically or functionally distinct CC regions, several geometric partitioning schemes have been proposed in the literature for morphometric analysis, subdividing CC into subregions whose fiber topography is expected to target different hemispheric cortical regions. A novel tool of morphometric analysis, based on the automated subdivision of a high number of partitions from a CC centroid and on the consequent determination of the CC anatomical landmarks is presented, allowing an automated analysis of CC volumes, shapes and curvatures, suitable for an automated application in clinical environment. Moreover the proposed tool can be used for original post-processing and visualization techniques that may help in the analysis of possible alterations of CC and in the correlations with autism-related diseases. The proposed morphometric tool has been validated and applied for clinical investigation on brain morphometry in children (age 3-11 years) with autism or with other autism spectrum disorders (DSA) and on healthy control subjects who underwent volumetric MRI T1 weighted acquisitions.

  9. Working Memory and Corpus Callosum Microstructural Integrity after Pediatric Traumatic Brain Injury: A Diffusion Tensor Tractography Study

    PubMed Central

    Treble, Amery; Hasan, Khader M.; Iftikhar, Amal; Stuebing, Karla K.; Kramer, Larry A.; Cox, Charles S.; Swank, Paul R.

    2013-01-01

    Abstract Deficits in working memory (WM) are a common consequence of pediatric traumatic brain injury (TBI) and are believed to contribute to difficulties in a range of cognitive and academic domains. Reduced integrity of the corpus callosum (CC) after TBI may disrupt the connectivity between bilateral frontoparietal neural networks underlying WM. In the present investigation, diffusion tensor imaging (DTI) tractography of eight callosal subregions (CC1–CC8) was examined in relation to measures of verbal and visuospatial WM in 74 children sustaining TBI and 49 typically developing comparison children. Relative to the comparison group, children with TBI demonstrated poorer visuospatial WM, but comparable verbal WM. Microstructure of the CC was significantly compromised in brain-injured children, with lower fractional anisotropy (FA) and higher axial and radial diffusivity metrics in all callosal subregions. In both groups of children, lower FA and/or higher radial diffusivity in callosal subregions connecting anterior and posterior parietal cortical regions predicted poorer verbal WM, whereas higher radial diffusivity in callosal subregions connecting anterior and posterior parietal, as well as temporal, cortical regions predicted poorer visuospatial WM. DTI metrics, especially radial diffusivity, in predictive callosal subregions accounted for significant variance in WM over and above remaining callosal subregions. Reduced microstructural integrity of the CC, particularly in subregions connecting parietal and temporal cortices, may act as a neuropathological mechanism contributing to long-term WM deficits. The future clinical use of neuroanatomical biomarkers may allow for the early identification of children at highest risk for WM deficits and earlier provision of interventions for these children. PMID:23627735

  10. Segmentation and Analysis of Corpus Callosum in Alzheimer MR Images using Total Variation Based Diffusion Filter and Level Set Method.

    PubMed

    Anandh, K R; Sujatha, C M; Ramakrishnan, S

    2015-01-01

    Alzheimer’s Disease (AD) is a common form of dementia that affects gray and white matter structures of brain. Manifestation of AD leads to cognitive deficits such as memory impairment problems, ability to think and difficulties in performing day to day activities. Although the etiology of this disease is unclear, imaging biomarkers are highly useful in the early diagnosis of AD. Magnetic resonance imaging is an indispensible non-invasive imaging modality that reflects both the geometry and pathology of the brain. Corpus Callosum (CC) is the largest white matter structure as well as the main inter-hemispheric fiber connection that undergoes regional alterations due to AD. Therefore, segmentation and feature extraction are predominantly essential to characterize the CC atrophy. In this work, an attempt has been made to segment CC using edge based level set method. Prior to segmentation, the images are pre-processed using Total Variation (TV) based diffusion filtering to enhance the edge information. Shape based geometric features are extracted from the segmented CC images to analyze the CC atrophy. Results show that the edge based level set method is able to segment CC in both the normal and AD images. TV based diffusion filtering has performed uniform region specific smoothing thereby preserving the texture and small scale details of the image. Consequently, the edge map of CC in both the normal and AD are apparently sharp and distinct with continuous boundaries. This facilitates the final contour to correctly segment CC from the nearby structures. The extracted geometric features such as area, perimeter and minor axis are found to have the percentage difference of 5.97%, 22.22% and 9.52% respectively in the demarcation of AD subjects. As callosal atrophy is significant in the diagnosis of AD, this study seems to be clinically useful.

  11. Properties and fate of oligodendrocyte progenitor cells in the corpus callosum, motor cortex, and piriform cortex of the mouse.

    PubMed

    Clarke, Laura E; Young, Kaylene M; Hamilton, Nicola B; Li, Huiliang; Richardson, William D; Attwell, David

    2012-06-13

    Oligodendrocyte progenitor cells (OPCs) in the postnatal mouse corpus callosum (CC) and motor cortex (Ctx) reportedly generate only oligodendrocytes (OLs), whereas those in the piriform cortex may also generate neurons. OPCs have also been subdivided based on their expression of voltage-gated ion channels, ability to respond to neuronal activity, and proliferative state. To determine whether OPCs in the piriform cortex have inherently different physiological properties from those in the CC and Ctx, we studied acute brain slices from postnatal transgenic mice in which GFP expression identifies OL lineage cells. We whole-cell patch clamped GFP-expressing (GFP(+)) cells within the CC, Ctx, and anterior piriform cortex (aPC) and used prelabeling with 5-ethynyl-2'-deoxyuridine (EdU) to assess cell proliferation. After recording, slices were immunolabeled and OPCs were defined by strong expression of NG2. NG2(+) OPCs in the white and gray matter proliferated and coexpressed PDGFRα and voltage-gated Na(+) channels (I(Na)). Approximately 70% of OPCs were capable of generating regenerative depolarizations. In addition to OLIG2(+) NG2(+) I(Na)(+) OPCs and OLIG2(+) NG2(neg) I(Na)(neg) OLs, we identified cells with low levels of NG2 limited to the soma or the base of some processes. These cells had a significantly reduced I(Na) and a reduced ability to incorporate EdU when compared with OPCs and probably correspond to early differentiating OLs. By combining EdU labeling and lineage tracing using Pdgfrα-CreER(T2) : R26R-YFP transgenic mice, we double labeled OPCs and traced their fate in the postnatal brain. These OPCs generated OLs but did not generate neurons in the aPC or elsewhere at any time that we examined.

  12. Clinical outcomes and neurodevelopmental outcome of prenatally diagnosed agenesis of corpus callosum in single center of Korea

    PubMed Central

    Kim, Sung Eun; Jang, Hye-In; Chang, Kylie Hae-jin; Sung, Ji-Hee; Lee, Jiwon; Lee, Jeehun; Choi, Suk-Joo; Roh, Cheong-Rae; Kim, Jong-Hwa

    2017-01-01

    Objective With recent advances and frequent use of prenatal ultrasound, the antenatal diagnosis of agenesis of the corpus callosum (ACC) is not rare in obstetrics practices. However, information regarding the long-term neurological outcome remains uncertain. The aim of this study was to investigate clinical outcomes of prenatally diagnosed ACC and to analyze postnatal neurodevelopmental outcomes of ACC neonates born in our single center. Methods We retrospectively reviewed 56 cases of prenatally suspected ACC referred to our center. Results Fifty-six fetuses were diagnosed with ACC, and 12 of those were followed-up in our center until delivery. Of the remaining 44, 7 were delivered after being referred back to the original hospital, 23 were lost to follow-up, and 14 had unknown outcomes. Among all 56, 29 were considered to have isolated ACC and 27 were considered to have non-isolated ACC. Of the 10 live fetuses delivered in our center, four had isolated ACC, three had non-isolated ACC, and the rest had outcomes unrelated to ACC. Neurodevelopmental outcome was followed-up until approximately age 3 years. Of the four with isolated ACC, three (75%) had normal neurodevelopmental outcomes. Conclusion Similar to other studies, the results of our single-center study included positive neurodevelopmental outcomes for those with isolated ACC. However, despite our endeavor to counsel patients with prenatally diagnosed ACC, the delivery rate in our center was quite low. Therefore, larger, multicenter, retrospective studies including long-term neurological development outcomes are crucial and urgently needed to provide better counseling. PMID:28217666

  13. Cuprizone demyelination of the corpus callosum in mice correlates with altered social interaction and impaired bilateral sensorimotor coordination.

    PubMed

    Hibbits, Norah; Pannu, Ravinder; Wu, T John; Armstrong, Regina C

    2009-08-14

    For studies of remyelination in demyelinating diseases, the cuprizone model of CC (corpus callosum) demyelination has experimental advantages that include overall size, proximity to neural stem cells of the subventricular zone, and correlation with a lesion predilection site in multiple sclerosis. In addition, cuprizone treatment can be ended to allow more direct analysis of remyelination than with viral or autoimmune models. However, CC demyelination lacks a useful functional correlate in rodents for longitudinal analysis throughout the course of demyelination and remyelination. In the present study, we tested two distinct behavioural measurements in mice fed 0.2% cuprizone. Running on a 'complex' wheel with varied rung intervals requires integration between cerebral hemispheres for rapid bilateral sensorimotor coordination. Maximum running velocity on the 'complex' wheel decreased during acute (6 week) and chronic (12 week) cuprizone demyelination. Running velocity on the complex wheel distinguished treated (for 6 weeks) from non-treated mice, even after a 6-week recovery period for spontaneous remyelination. A second behavioural assessment was a resident-intruder test of social interaction. The frequency of interactive behaviours increased among resident mice after acute or chronic demyelination. Differences in both sensorimotor coordination and social interaction correlated with demonstrated CC demyelination. The wheel assay is applicable for longitudinal studies. The resident-intruder assay provides a complementary assessment of a distinct modality at a specific time point. These behavioural measurements are sufficiently robust for small cohorts as a non-invasive assessment of demyelination to facilitate analysis of subsequent remyelination. These measurements may also identify CC involvement in other mouse models of central nervous system injuries and disorders.

  14. 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

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

    PubMed Central

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

    2014-01-01

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

  16. 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

  17. 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.

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

    PubMed Central

    Casaubon, L. K.; Melanson, M.; Lopes-Cendes, I.; Marineau, C.; Andermann, E.; Andermann, F.; Weissenbach, J.; Prévost, C.; Bouchard, J. P.; Mathieu, J.; Rouleau, G. A.

    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 the progressive peripheral neuropathy or agenesis of the corpus callosum. PMID:8554065

  19. Absence of anatomic corpus callosal abnormalities in childhood-onset schizophrenia patients and healthy siblings.

    PubMed

    Johnson, Sarah L M; Greenstein, Deanna; Clasen, Liv; Miller, Rachel; Lalonde, Francois; Rapoport, Judith; Gogtay, Nitin

    2013-01-30

    The corpus callosum (CC) has been implicated in the pathogenesis of schizophrenia, and CC deficits have been reported in adults with schizophrenia. We explored the developmental trajectory of the corpus callosum in childhood-onset schizophrenia (COS) patients, their healthy siblings (SIB) and healthy volunteers. We obtained 235 anatomic brain magnetic resonance imaging (MRI) scans from 98 COS patients, 153 scans from 71 of their healthy siblings, and 253 scans from 100 age- and gender-matched healthy volunteers, across ages 9-30 years. The volumes of five sub-regions of the CC were calculated using FreeSurfer, and summed to give the total volume. Longitudinal data were examined using mixed model regression analysis. There were no significant differences for the total or sub-regional CC volumes between the three groups. There were also no significant differences between the groups for developmental trajectory (slope) of the CC. This is the largest longitudinal study of CC development in schizophrenia and the first COS study of the CC to include healthy siblings. Overall, CC volume and growth trajectory did not differ between COS patients, healthy siblings, or healthy volunteers. These results suggest that CC development, at least at a macroscopic level, may not be a salient feature of schizophrenia.

  20. Diffusion tensor quantification and cognitive correlates of the macrostructure and microstructure of the corpus callosum in typically developing and dyslexic children.

    PubMed

    Hasan, Khader M; Molfese, David L; Walimuni, Indika S; Stuebing, Karla K; Papanicolaou, Andrew C; Narayana, Ponnada A; Fletcher, Jack M

    2012-11-01

    Noninvasive quantitative MRI methods, such as diffusion tensor imaging (DTI), can offer insights into the structure-function relationships in human developmental brain disorders. In this article, we quantified the macrostructural and microstructural attributes of the corpus callosum (CC) in children with dyslexia and in typically developing readers of comparable age and gender. Diffusion anisotropy, and mean, radial and axial diffusivities of cross-sectional CC subregions were computed using a validated DTI methodology. The normalized posterior CC area was enlarged in children with dyslexia relative to that in typically developing children. Moreover, the callosal microstructural attributes, such as the mean diffusivity of the posterior middle sector of the CC, correlated significantly with measures of word reading and reading comprehension. Reading group differences in fractional anisotropy, mean diffusivity and radial diffusivity were observed in the posterior CC (CC5). This study demonstrates the utility of regional DTI measurements of the CC in understanding the neurobiology of reading disorders.

  1. Gelastic epilepsy in combination with hypothalamic hamartoma and partial agenesis of the corpus callosum: A case report and review of the literature.

    PubMed

    Cheng, Bochao; Sun, Chongran; Li, Shiguang; Gong, Qiyong; Lui, Su

    2013-12-01

    Gelastic epilepsy has been reported to originate from various conditions, particularly from hypothalamic hamartoma (HH). In the present study, we report a patient with gelastic seizures (GSs), followed by complex partial and tonic-clonic seizures. Magnetic resonance imaging (MRI) revealed a rare combination of HH and partial agenesis of the corpus callosum (ACC). Following resectioning of the HH, the seizures were reduced, but not fully controlled, with medication by the one year follow-up. HH and partial ACC patients may experience seizures; the seizures in the case presented in this study may have originated from HH, partial ACC or both. Considering the fact that seizure frequency reduced following surgery, they may have mainly occurred from HH. Additionally it was considered to be likely that the seizures following surgery were due to secondary epileptogenesis, partial ACC, or both.

  2. Gelastic epilepsy in combination with hypothalamic hamartoma and partial agenesis of the corpus callosum: A case report and review of the literature

    PubMed Central

    CHENG, BOCHAO; SUN, CHONGRAN; LI, SHIGUANG; GONG, QIYONG; LUI, SU

    2013-01-01

    Gelastic epilepsy has been reported to originate from various conditions, particularly from hypothalamic hamartoma (HH). In the present study, we report a patient with gelastic seizures (GSs), followed by complex partial and tonic-clonic seizures. Magnetic resonance imaging (MRI) revealed a rare combination of HH and partial agenesis of the corpus callosum (ACC). Following resectioning of the HH, the seizures were reduced, but not fully controlled, with medication by the one year follow-up. HH and partial ACC patients may experience seizures; the seizures in the case presented in this study may have originated from HH, partial ACC or both. Considering the fact that seizure frequency reduced following surgery, they may have mainly occurred from HH. Additionally it was considered to be likely that the seizures following surgery were due to secondary epileptogenesis, partial ACC, or both. PMID:24255688

  3. Diffusion Tensor Quantification and Cognitive Correlates of the Macrostructure and Microstructure of the Corpus Callosum in Typically Developing Children and Dyslexics

    PubMed Central

    Hasan, Khader M.; Molfese, David L.; Walimuni, Indika S.; Stuebing, Karla K.; Papanicolaou, Andrew C.; Narayana, Ponnada A.; Fletcher, Jack M.

    2012-01-01

    Noninvasive quantitative magnetic resonance imaging methods such as diffusion tensor imaging (DTI), can offer insights into structure/function relationships in human developmental brain disorders. In this report, we quantified macrostructural and microstructural attributes of the corpus callosum (CC) in children with dyslexia and typically developing readers of comparable age and gender. Diffusion anisotropy, mean, radial and axial diffusivities of cross-sectional CC sub-regions were computed using a validated DTI methodology. The normalized posterior CC area was enlarged in children with dyslexia compared to typically developing children. Moreover, the callosal microstructural attributes, such as mean diffusivity of the posterior middle sector of the CC, significantly correlated with measures of word reading and reading comprehension. Reading group differences in FA, MD, and RD were observed in the posterior CC (CC5). This study demonstrates the utility of regional DTI measurements of the CC in understanding the neurobiology of reading disorders. PMID:22411286

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

    PubMed

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

    2014-10-01

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

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

    PubMed

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

    2016-06-01

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

  6. 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.

  7. 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

  8. Sex-related difference in human white matter volumes studied: Inspection of the corpus callosum and other white matter by VBM

    PubMed Central

    Shiino, Akihiko; Chen, Yen-wei; Tanigaki, Kenji; Yamada, Atsushi; Vigers, Piers; Watanabe, Toshiyuki; Tooyama, Ikuo; Akiguchi, Ichiro

    2017-01-01

    It has been contended that any observed difference of the corpus callosum (CC) size between men and women is not sex-related but brain-size-related. A recent report, however, showed that the midsagittal CC area was significantly larger in women in 37 brain-size-matched pairs of normal young adults. Since this constituted strong evidence of sexual dimorphism and was obtained from publicly available data in OASIS, we examined volume differences within the CC and in other white matter using voxel-based morphometry (VBM). We created a three-dimensional region of interest of the CC and measured its volume. The VBM statistics were analyzed by permutation test and threshold-free cluster enhancement (TFCE) with the significance levels at FWER < 0.05. The CC volume was significantly larger in women in the same 37 brain-size-matched pairs. We found that the CC genu was the subregion showing the most significant sex-related difference. We also found that white matter in the bilateral anterior frontal regions and the left lateral white matter near to Broca’s area were larger in women, whereas there were no significant larger regions in men. Since we used brain-size-matched subjects, our results gave strong volumetric evidence of localized sexual dimorphism of white matter. PMID:28045130

  9. Brief Report: VAX1 mutation associated with microphthalmia, corpus callosum agenesis and orofacial clefting – the first description of a VAX1 phenotype in humans

    PubMed Central

    Slavotinek, Anne M.; Chao, Ryan; Vacik, Tomas; Yahyavi, Mani; Abouzeid, Hana; Bardakjian, Tanya; Schneider, Adele; Shaw, Gary; Sherr, Elliott H.; Lemke, Greg; Youssef, Mohammed; Schorderet, Daniel F.

    2011-01-01

    Vax1 and Vax2 have been implicated in eye development and the closure of the choroid fissure in mice and zebrafish. We sequenced the coding exons of VAX1 and VAX2 in 70 patients with anophthalmia/microphthalmia. In VAX1, we observed homozygosity for two successive nucleotide substitutions c.453G>A and c.454C>A, predicting p.Arg152Ser, in a proband of Egyptian origin with microphthalmia, small optic nerves, cleft lip/palate and corpus callosum agenesis. This mutation affects an invariant residue in the homeodomain of VAX1 and was absent from 96 Egyptian controls. It is likely that the mutation results in a loss of function, as the mutation results in a phenotype similar to the Vax1 homozygous null mouse. We did not identify any mutations in VAX2. This is the first description of a phenotype associated with a VAX1 mutation in humans and establishes VAX1 as a new causative gene for anophthalmia/microphthalmia. PMID:22095910

  10. [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.

  11. Adult-onset deficiency in growth hormone and insulin-like growth factor-I alters oligodendrocyte turnover in the corpus callosum.

    PubMed

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

    2009-08-01

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

  12. Comparison between skeleton-based and atlas-based approach in the assessment of corpus callosum damages in Mild Cognitive Impairment and Alzheimer Disease.

    PubMed

    Preti, Maria Giulia; Laganà, Maria Marcella; Baglio, Francesca; Griffanti, Ludovica; Nemni, Raffaello; Cecconi, Pietro; Baselli, Giuseppe

    2011-01-01

    The damage of specific bundles in the brain white matter (WM) is currently assessed in Alzheimer Disease (AD) and amnestic Mild Cognitive Impairment (aMCI) by tractography based on diffusion tensor imaging (DTI) and the consequent evaluation of diffusion parameters in reconstructed tracts. Controversial results may be due to the use of different techniques. This work aims at comparing an atlas-based technique to compute fractional anisotropy (FA) in specific tracts with the voxelwise approach of Tract-Based Spatial Statistics (TBSS). FA was evaluated in 7 portions of the corpus callosum (CC) of 10 elderly healthy controls (HC), 10 aMCI and 10 mild AD patients with both approaches. Atlas-based tractography revealed concordant results with TBSS, displaying the same significant differences between AD and HC and no significant difference between aMCI and HC. However, as regards the AD to aMCI contrast only the atlas-based method was able to find significantly lowered FA in AD in frontal and parietal CC portions. This finding shows that a proper analysis which considers a higher number of voxels, not restricting the observation to the skeleton in the assessment of CC damages, could be useful for AD to aMCI differential diagnosis and prognosis.

  13. Mirror Motor Activity During Right-Hand Contractions and Its Relation to White Matter in the Posterior Midbody of the Corpus Callosum.

    PubMed

    Sehm, Bernhard; Steele, Christoper J; Villringer, Arno; Ragert, Patrick

    2015-09-22

    Cortical activity during simple unimanual actions is typically lateralized to contralateral sensorimotor areas, while a more bilateral pattern is observed with an increase in task demands. In parallel, increasing task demands are associated with subtle mirror muscle activity in the resting hand, implying a relative loss in motor selectivity. The corpus callosum (CC) is crucially involved in unimanual tasks by mediating both facilitatory and inhibitory interactions between bilateral motor cortical systems, but its association with mirror motor activity is yet unknown. Here, we used diffusion-weighted imaging and bilateral electromyographic (EMG) measurements during a unimanual task to investigate potential relationships between white matter microstructure of the CC and mirror EMG activity. Participants performed an unimanual pinch force task with both hands alternatively. Four parametrically increasing force levels were exerted while EMG activity was recorded bilaterally from first dorsal interosseus muscles. Consistent with previous findings, mirror EMG activity increased as a function of force. Additionally, there was a significant relationship between the slope of increasing mirror EMG during right-hand contractions and fractional anisotropy in transcallosal fibers connecting both M1. No significant relationships were found for fibers connecting dorsal premotor cortices or supplementary motor area, indicating the local specificity of the observed brain-physiology relationship.

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. Sex-related difference in human white matter volumes studied: Inspection of the corpus callosum and other white matter by VBM

    NASA Astrophysics Data System (ADS)

    Shiino, Akihiko; Chen, Yen-Wei; Tanigaki, Kenji; Yamada, Atsushi; Vigers, Piers; Watanabe, Toshiyuki; Tooyama, Ikuo; Akiguchi, Ichiro

    2017-01-01

    It has been contended that any observed difference of the corpus callosum (CC) size between men and women is not sex-related but brain-size-related. A recent report, however, showed that the midsagittal CC area was significantly larger in women in 37 brain-size-matched pairs of normal young adults. Since this constituted strong evidence of sexual dimorphism and was obtained from publicly available data in OASIS, we examined volume differences within the CC and in other white matter using voxel-based morphometry (VBM). We created a three-dimensional region of interest of the CC and measured its volume. The VBM statistics were analyzed by permutation test and threshold-free cluster enhancement (TFCE) with the significance levels at FWER < 0.05. The CC volume was significantly larger in women in the same 37 brain-size-matched pairs. We found that the CC genu was the subregion showing the most significant sex-related difference. We also found that white matter in the bilateral anterior frontal regions and the left lateral white matter near to Broca’s area were larger in women, whereas there were no significant larger regions in men. Since we used brain-size-matched subjects, our results gave strong volumetric evidence of localized sexual dimorphism of white matter.

  19. 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.

  20. The effect of age, sex and clinical features on the volume of Corpus Callosum in pre-schoolers with Autism Spectrum Disorder: a case-control study.

    PubMed

    Giuliano, Alessia; Saviozzi, Irene; Brambilla, Paolo; Muratori, Filippo; Retico, Alessandra; Calderoni, Sara

    2017-01-23

    A growing body of literature has identified volume alterations of the corpus callosum (CC) in subjects with autism spectrum disorders (ASD). However, to date very few investigations have been conducted on pre-school-age ASD children. This study aims to compare the volume of CC and its sub-regions between pre-schoolers with ASD and controls (CON) and to examine their relationship to demographic and clinical variables (sex, age, non-verbal IQ -NVIQ-, expressive non-echolalic language, emotional and behavioural problems, and autism severity). The volume of CC of 40 pre-schoolers with ASD (20 males and 20 females; mean age: 49 ± 12 months; mean NVIQ: 73 ± 22) and 40 sex-, age-, and NVIQ-matched CON subjects (20 M and 20 F; mean age: 49 ± 14 months; mean NVIQ: 73 ± 23) were quantified applying the FreeSurfer automated parcellation software on Magnetic Resonance images. No significant volumetric differences in CC total volume and in its sub-regions between ASD and CON were found using total brain volume as a covariate. Analogously, absence of CC volumetric differences was evident when boys and girls with ASD were compared with their matched controls. The CC total volume of younger ASD male subjects was found significantly larger with respect to matched CON, which is consistent with the atypical growth trajectory widely reported in these young children. The CC total volume was negatively correlated with autism severity, whereas no association between CC volume and other clinical variables was detected. If replicated, the indirect relationship between CC volume and autism severity suggests the involvement of CC in core ASD symptoms.

  1. Recovery of axonal myelination sheath and axonal caliber in the mouse corpus callosum following damage induced by N,N-diethyldithiocarbamate.

    PubMed

    Utrera, Juana; Romero, Rafael; Verdaguer, Ester; Junyent, Fèlix; Auladell, Carme

    2011-12-01

    Disulfiram is an aldehyde dehydrogenase inhibitor used for the treatment of alcohol dependence and of cocaine addiction. It has been demonstrated that subchronic administration of disulfiram or N,N-diethyldithiocarbamate (DEDTC), the main derivative of disulfiram, to rats can produce central-peripheral distal axonopathy. However, few data regarding the axonal effects of these compounds in the central nervous system exist. Our previous studies have revealed DEDTC-induced axonal damage in the mouse brain during the course of postnatal development, together with alterations in axonal pathfinding and in the myelination process, with partial recovery during the post-treatment period. In order to gather new data about how this axonal damage and recovery occurs in the central nervous system, we performed an ultrastructural analysis of the axons located in the corpus callosum from mice treated with DEDTC during postnatal development. The axonal caliber throughout the axonal area, the maximum axonal diameter, the maximum fiber diameter, and the axonal circularity, at different postnatal stages [from postnatal day (P)9 to P30], were analyzed. In addition, parameters related to the myelinization process (number of myelinated axons, sheath thickness, and the ratio of myelinated axons to total axons) were evaluated. A reduction in the average value of axonal caliber during treatment and a delay in the axonal myelination process were detected. Whereas early recovery of individual axons occurred after treatment (P22), complete recovery of myelinated axons occurred at late postnatal stages (P42). Therefore, chronic treatment with dithiocarbamates requires periods of rest to encourage the recovery of myelinated axons.

  2. Impairment in explicit visuomotor sequence learning is related to loss of microstructural integrity of the corpus callosum in multiple sclerosis patients with minimal disability.

    PubMed

    Bonzano, L; Tacchino, A; Roccatagliata, L; Sormani, M P; Mancardi, G L; Bove, M

    2011-07-15

    Sequence learning can be investigated by serial reaction-time (SRT) paradigms. Explicit learning occurs when subjects have to recognize a test sequence and has been shown to activate the frontoparietal network in both contralateral and ipsilateral hemispheres. Thus, the left and right superior longitudinal fasciculi (SLF), connecting the intra-hemispheric frontoparietal circuits, could have a role in explicit unimanual visuomotor learning. Also, as both hemispheres are involved, we could hypothesize that the corpus callosum (CC) has a role in this process. Pathological damage in both SLF and CC has been detected in patients with Multiple Sclerosis (PwMS), and microstructural alterations can be quantified by Diffusion Tensor Imaging (DTI). In light of these findings, we inquired whether PwMS with minimal disability showed impairments in explicit visuomotor sequence learning and whether this could be due to loss of white matter integrity in these intra- and inter-hemispheric white matter pathways. Thus, we combined DTI analysis with a modified version of SRT task based on finger opposition movements in a group of PwMS with minimal disability. We found that the performance in explicit sequence learning was significantly reduced in these patients with respect to healthy subjects; the amount of sequence-specific learning was found to be more strongly correlated with fractional anisotropy (FA) in the CC (r=0.93) than in the left (r=0.28) and right SLF (r=0.27) (p for interaction=0.005 and 0.04 respectively). This finding suggests that an inter-hemispheric information exchange between the homologous areas is required to successfully accomplish the task and indirectly supports the role of the right (ipsilateral) hemisphere in explicit visuomotor learning. On the other hand, we found no significant correlation of the FA in the CC and in the SLFs with nonspecific learning (assessed when stimuli are randomly presented), supporting the hypothesis that inter

  3. The Microstructural Status of the Corpus Callosum Is Associated with the Degree of Motor Function and Neurological Deficit in Stroke Patients

    PubMed Central

    Liang, Fanrong; Huang, Wenhua

    2015-01-01

    Human neuroimaging studies and animal models have suggested that white matter damage from ischemic stroke leads to the functional and structural reorganization of perilesional and remote brain regions. However, the quantitative relationship between the transcallosal tract integrity and clinical motor performance score after stroke remains unexplored. The current study employed a tract-based spatial statistics (TBSS) analysis on diffusion tensor imaging (DTI) to investigate the relationship between white matter diffusivity changes and the clinical scores in stroke patients. Probabilistic fiber tracking was also used to identify structural connectivity patterns in the patients. Thirteen ischemic stroke patients and fifteen healthy control subjects participated in this study. TBSS analyses showed that the corpus callosum (CC) and bilateral corticospinal tracts (CST) in the stroke patients exhibited significantly decreased fractional anisotropy and increased axial and radial diffusivity compared with those of the controls. Correlation analyses revealed that the motor and neurological deficit scores in the stroke patients were associated with the value of diffusivity indices in the CC. Compared with the healthy control group, probabilistic fiber tracking analyses revealed that significant changes in the inter-hemispheric fiber connections between the left and right motor cortex in the stroke patients were primarily located in the genu and body of the CC, left anterior thalamic radiation and inferior fronto-occipital fasciculus, bilateral CST, anterior/superior corona radiate, cingulum and superior longitudinal fasciculus, strongly suggesting that ischemic induces inter-hemispheric network disturbances and disrupts the white matter fibers connecting motor regions. In conclusion, the results of the present study show that DTI-derived measures in the CC can be used to predict the severity of motor skill and neurological deficit in stroke patients. Changes in structural

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

    PubMed Central

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

    2015-01-01

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

  5. Agenesis of the Corpus Callosum

    MedlinePlus

    ... Chiari malformation, Dandy-Walker syndrome, schizencephaly (clefts or deep divisions in brain tissue), and holoprosencephaly (failure of ... Chiari malformation, Dandy-Walker syndrome, schizencephaly (clefts or deep divisions in brain tissue), and holoprosencephaly (failure of ...

  6. Clinical features and associated abnormalities in children and adolescents with corpus callosal anomalies.

    PubMed

    Kim, Young Uhk; Park, Eun Sook; Jung, Soojin; Suh, Miri; Choi, Hyo Seon; Rha, Dong-Wook

    2014-02-01

    Callosal anomalies are frequently associated with other central nervous system (CNS) and/or somatic anomalies. We retrospectively analyzed the clinical features of corpus callosal agenesis/hypoplasia accompanying other CNS and/or somatic anomalies. We reviewed the imaging and clinical information of patients who underwent brain magnetic resonance imaging in our hospital, between 2005 and 2012. Callosal anomalies were isolated in 13 patients, accompanied by other CNS anomalies in 10 patients, associated with only non-CNS somatic anomalies in four patients, and with both CNS and non-CNS abnormalities in four patients. Out of 31 patients, four developed normally, without impairments in motor or cognitive functions. Five of nine patients with cerebral palsy were accompanied by other CNS and/or somatic anomalies, and showed worse Gross Motor Function Classification System scores, compared with the other four patients with isolated callosal anomaly. In addition, patients with other CNS anomalies also had a higher seizure risk.

  7. Endoscopic posterior interhemispheric complete corpus callosotomy.

    PubMed

    Sood, Sandeep; Asano, Eishi; Altinok, Deniz; Luat, Aimee

    2016-12-01

    Traditionally corpus callosotomy is done through a craniotomy centered at the coronal suture, with the aid of a microscope. This involves dissecting through the interhemispheric fissure below the falx to reach the corpus callosum. The authors describe a posterior interhemispheric approach to complete corpus callosotomy with an endoscope, which bypasses the need to perform interhemispheric dissection because the falx is generally close to the corpus callosum in this region.

  8. High-Resolution Magnetic Resonance Microscopy and Diffusion Tensor Imaging to Assess Brain Structural Abnormalities in the Murine Mucopolysaccharidosis VII Model

    PubMed Central

    Poptani, Harish; Kumar, Manoj; Nasrallah, Ilya M; Kim, Sungheon; Ittyerah, Ranjit; Pickup, Stephen; Li, Joel; Parente, Michael K; Wolfe, John H.

    2014-01-01

    High-resolution microscopic magnetic resonance imaging (μMRI) and diffusion tensor imaging (DTI) were performed to characterize brain structural abnormalities in a mouse model of mucopolysaccharidosis type VII (MPS VII). μMRI demonstrated a decrease in the volume of anterior commissure and corpus callosum and a slight increase in the volume of the hippocampus in MPS VII vs. wild-type mice. DTI indices were analyzed in gray and white matter. In vivo and ex vivo DTI demonstrated significantly reduced fractional anisotropy in the anterior commissure, corpus callosum, external capsule and hippocampus in MPS VII vs. control brains. Significantly increased mean diffusivity was also found in the anterior commissure and corpus callosum from ex-vivo DTI. Significantly reduced linear anisotropy was observed from the hippocampus from in-vivo DTI, whereas significantly decreased planar anisotropy and spherical anisotropy were observed in the external capsule from only ex-vivo DTI. There were corresponding morphological differences in the brains of MPS VII mice by hematoxylin and eosin staining. Luxol fast blue staining demonstrated less intense staining of the corpus callosum and external capsule; myelin abnormalities in the corpus callosum were also demonstrated quantitatively in toluidine blue-stained sections and confirmed by electron microscopy. These results demonstrate the potential for μMRI and DTI for quantitative assessment of brain pathology in murine models of brain diseases. PMID:24335527

  9. Impaired visual short-term memory capacity is distinctively associated with structural connectivity of the posterior thalamic radiation and the splenium of the corpus callosum in preterm-born adults.

    PubMed

    Menegaux, Aurore; Meng, Chun; Neitzel, Julia; Bäuml, Josef G; Müller, Hermann J; Bartmann, Peter; Wolke, Dieter; Wohlschläger, Afra M; Finke, Kathrin; Sorg, Christian

    2017-02-07

    Preterm birth is associated with an increased risk for lasting changes in both the cortico-thalamic system and attention; however, the link between cortico-thalamic and attention changes is as yet little understood. In preterm newborns, cortico-cortical and cortico-thalamic structural connectivity are distinctively altered, with increased local clustering for cortico-cortical and decreased integrity for cortico-thalamic connectivity. In preterm-born adults, among the various attention functions, visual short-term memory (vSTM) capacity is selectively impaired. We hypothesized distinct associations between vSTM capacity and the structural integrity of cortico-thalamic and cortico-cortical connections, respectively, in preterm-born adults. A whole-report paradigm of briefly presented letter arrays based on the computationally formalized Theory of Visual Attention (TVA) was used to quantify parameter vSTM capacity in 26 preterm- and 21 full-term-born adults. Fractional anisotropy (FA) of posterior thalamic radiations and the splenium of the corpus callosum obtained by diffusion tensor imaging were analyzed by tract-based spatial statistics and used as proxies for cortico-thalamic and cortico-cortical structural connectivity. The relationship between vSTM capacity and cortico-thalamic and cortico-cortical connectivity, respectively, was significantly modified by prematurity. In full-term-born adults, the higher FA in the right posterior thalamic radiation the higher vSTM capacity; in preterm-born adults this FA-vSTM-relationship was inversed. In the splenium, higher FA was correlated with higher vSTM capacity in preterm-born adults, whereas no significant relationship was evident in full-term-born adults. These results indicate distinct associations between cortico-thalamic and cortico-cortical integrity and vSTM capacity in preterm-and full-term-born adults. Data suggest compensatory cortico-cortical fiber re-organization for attention deficits after preterm delivery.

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

    PubMed

    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

    2012-02-01

    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.

  11. 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…

  12. Anatomical Abnormalities in Autism?

    PubMed

    Haar, Shlomi; Berman, Sigal; Behrmann, Marlene; Dinstein, Ilan

    2016-04-01

    Substantial controversy exists regarding the presence and significance of anatomical abnormalities in autism spectrum disorders (ASD). The release of the Autism Brain Imaging Data Exchange (∼1000 participants, age 6-65 years) offers an unprecedented opportunity to conduct large-scale comparisons of anatomical MRI scans across groups and to resolve many of the outstanding questions. Comprehensive univariate analyses using volumetric, thickness, and surface area measures of over 180 anatomically defined brain areas, revealed significantly larger ventricular volumes, smaller corpus callosum volume (central segment only), and several cortical areas with increased thickness in the ASD group. Previously reported anatomical abnormalities in ASD including larger intracranial volumes, smaller cerebellar volumes, and larger amygdala volumes were not substantiated by the current study. In addition, multivariate classification analyses yielded modest decoding accuracies of individuals' group identity (<60%), suggesting that the examined anatomical measures are of limited diagnostic utility for ASD. While anatomical abnormalities may be present in distinct subgroups of ASD individuals, the current findings show that many previously reported anatomical measures are likely to be of low clinical and scientific significance for understanding ASD neuropathology as a whole in individuals 6-35 years old.

  13. 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.

  14. Pathogenetic transition in the morphology of abnormal sperm in the testes and the caput, corpus, and cauda epididymides of male rats after treatment with 4,6-dinitro-o-cresol.

    PubMed

    Takahashi, Ken L; Takahashi, Naofumi; Hojo, Hitoshi; Kuwahara, Maki; Aoyama, Hiroaki; Teramoto, Shoji

    2006-10-01

    In order to elucidate the pathogenesis of tailless sperm, 4,6-dinitro-o-cresol (DNOC) was administered to Jcl:SD male rats at daily oral doses of 0, 10 or 15mg/kg for 5 days. Sperm were collected from the caput, corpus, and cauda epididymides on days 1, 7 and 14 after the last dosing (D1, D7 and D14, respectively), counted and examined morphologically by phase-contrast and scanning electron microscopy. The incidence of abnormal sperm was significantly increased in the DNOC 15mg/kg group. On D1, peeled sperm (loss of mitochondrial sheath at the proximal end of the middle piece) was frequently observed in the caput epididymides, whereas sperm in the corpus and cauda epididymides had normal morphology. Distribution of the peeled sperm changed as time passed and the corpus epididymides showed a peak incidence on D7. On D14, the highest incidence of abnormal sperm was observed in the cauda epididymides, where the major abnormality was tailless. Similar effects were also found in the 10mg/kg group but were less potent. Transmission electron microscopy of testicular sperm on D1 revealed the presence of elongated spermatids that lacked the mitochondrial sheath at the proximal end of the middle piece, although the round and elongating spermatids looked normal. These results suggest that DNOC exposure of male rats primarily causes partial loss of the mitochondrial sheath in the testicular elongated spermatids, and that the affected sperm become tailless by D14 after reaching the cauda epididymides.

  15. Positive correlations between corpus callosum thickness and intelligence.

    PubMed

    Luders, Eileen; Narr, Katherine L; Bilder, Robert M; Thompson, Paul M; Szeszko, Philip R; Hamilton, Liberty; Toga, Arthur W

    2007-10-01

    Callosal morphology is thought to reflect the capacity for inter-hemispheric communication and thus, in addition to other cerebral characteristics, may serve as a neuroanatomical substrate of general intellectual capacity. We applied novel computational mesh-based methods to establish the presence and direction of correlations between intelligence and callosal thickness at high spatial resolution while removing the variance associated with overall brain size. Within healthy subjects (n=62), and within males (n=28) and females (n=34) separately, we observed significant positive correlations between callosal morphology and intelligence measures (full-scale, performance, and verbal). These relationships were pronounced in posterior callosal sections and were confirmed by permutation testing. Significant negative correlations were absent. Positive associations between intelligence and posterior callosal thickness may reflect a more efficient inter-hemispheric information transfer, positively affecting information processing and integration, and thus intellectual performance. At the same time, regional variations in callosal size might also partly reflect the underlying architecture of topographically connected cortical regions relevant for processing higher-order cognitive information. Our findings emphasize the importance of incorporating posterior (callosal) regions into the theories and models proposed to explain the anatomical substrates of intelligence.

  16. 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…

  17. 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)

  18. Minimally Invasive Robotic Laser Corpus Callosotomy: A Proof of Concept

    PubMed Central

    Essayed, Walid I; Deb, Sayantan; Hoffman, Caitlin; Schwartz, Theodore H

    2017-01-01

    Introduction We describe the feasibility of using minimally invasive robotic laser interstitial thermotherapy (LITT) for achieving an anterior two-thirds as well as a complete corpus callosotomy. Methods Ten probe trajectories were plotted on normal magentic resonance imaging (MRI) scans using the Brainlab Stereotactic Planning Software (Brainlab, Munich, Germany). The NeuroBlate® System (Monteris Medical, MN, USA) was used to conform the thermal burn to the corpus callosum along the trajectory of the probe. The distance of the ideal entry site from either the coronal suture and the torcula or nasion and the midline was calculated. The distance of the probe tip from the dorsal and ventral limits of the callosotomy in the sagittal plane were also calculated. Results Anterior two-thirds callosotomy was possible in all patients using a posterior parieto-occipital paramedian trajectory through the non-dominant lobe. The average entry point was 3.64 cm from the midline, 10.6 cm behind the coronal suture, and 9.2 cm above the torcula. The probe tip was an average of 1.4 cm from the anterior commissure. For a total callosotomy, an additional contralaterally placed frontal probe was used to target the posterior one-third of the corpus callosum. The average entry site was 3.3 cm from the midline and 9.1 cm above the nasion. The average distance of the probe tip from the base of the splenium was 0.94 cm. Conclusion The directional thermoablation capability of the NeuroBlate® system allows for targeted lesioning of the corpus callosum, to achieve a two-thirds or complete corpus callosotomy. A laser distance of < 2 cm is sufficient to reach the entire corpus callosum through one trajectory for an anterior two-thirds callosotomy and two trajectories for a complete callosotomy. PMID:28348940

  19. Abnormal asymmetry of brain connectivity in schizophrenia.

    PubMed

    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.

  20. Microstructural callosal abnormalities in normal-appearing brain of children with developmental delay detected with diffusion tensor imaging.

    PubMed

    Ding, Xiao-Qi; Sun, Yimeng; Kruse, Bernd; Illies, Till; Zeumer, Hermann; Fiehler, Jens; Lanfermann, Heinrich

    2009-06-01

    Callosal fibres play an important role in psychomotor and cognitive functions. The purpose of this study was to investigate possible microstructural abnormalities of the corpus callosum in children with developmental delay, who have normal conventional brain MR imaging results. Seventeen pediatric patients (aged 1-9 years) with developmental delay were studied. Quantitative T2 and fractional anisotropy (FA) values were measured at the genu and splenium of the corpus callosum (CC). Fibre tracking, volumetric determination, as well as fibre density calculations of the CC were also carried out. The results were compared with those of the age-matched healthy subjects. A general elevation of T2 relaxation times (105 ms in patients vs. 95 ms in controls) and reduction of the FA values (0.66 in patients vs. 0.74 in controls) at the genu of the CC were found in patients. Reductions of the fibre numbers (5,464 in patients vs. 8,886 in controls) and volumes (3,415 ml in patients vs. 5,235 ml in controls) of the CC were found only in patients older than 5 years. The study indicates that despite their inconspicuous findings in conventional MRI microstructural brain abnormalities are evident in these pediatric patients suffering from developmental delay.

  1. 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.

  2. 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.

  3. Repetitive Model of Mild Traumatic Brain Injury Produces Cortical Abnormalities Detectable by Magnetic Resonance Diffusion Imaging (DTI/DKI), Histopathology, and Behavior.

    PubMed

    Yu, Fengshan; Shukla, Dinesh K; Armstrong, Regina C; Marion, Christina M; Radomski, Kryslaine L; Selwyn, Reed G; Dardzinski, Bernard J

    2016-12-20

    Noninvasive detection of mild traumatic brain injury (mTBI) is important for evaluating acute through chronic effects of head injuries, particularly after repetitive impacts. To better detect abnormalities from mTBI, we performed longitudinal studies (baseline, 3, 6, and 42 days) using magnetic resonance diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI) in adult mice after repetitive mTBI (r-mTBI; daily × 5) or sham procedure. This r-mTBI produced righting reflex delay and was first characterized in the corpus callosum to demonstrate low levels of axon damage, astrogliosis, and microglial activation, without microhemorrhages. High-resolution DTI-DKI was then combined with post-imaging pathological validation along with behavioral assessments targeted for the impact regions. In the corpus callosum, only DTI fractional anisotropy at 42 days showed significant change post-injury. Conversely, cortical regions under the impact site (M1-M2, anterior cingulate) had reduced axial diffusivity (AD) at all time points with a corresponding increase in axial kurtosis (Ka) at 6 days. Post-imaging neuropathology showed microglial activation in both the corpus callosum and cortex at 42 days after r-mTBI. Increased cortical microglial activation correlated with decreased cortical AD after r-mTBI (r = -0.853; n = 5). Using Thy1-YFP-16 mice to fluorescently label neuronal cell bodies and processes revealed low levels of axon damage in the cortex after r-mTBI. Finally, r-mTBI produced social deficits consistent with the function of this anterior cingulate region of cortex. Overall, vulnerability of cortical regions is demonstrated after mild repetitive injury, with underlying differences of DTI and DKI, microglial activation, and behavioral deficits.

  4. Extensive abnormality of brain white matter integrity in pathological gambling.

    PubMed

    Joutsa, Juho; Saunavaara, Jani; Parkkola, Riitta; Niemelä, Solja; Kaasinen, Valtteri

    2011-12-30

    Several magnetic resonance imaging (MRI) studies in substance use disorders have shown brain white matter integrity abnormalities, but there are no studies in pathological gambling, a form of behavioral addiction. Our objective was to investigate possible changes in regional brain gray and white matter volumes, and axonal white matter integrity in pathological gamblers compared to healthy controls. Twenty-four subjects (12 clinically diagnosed male pathological gamblers and 12 age-matched healthy male volunteers) underwent structural and diffusion weighted brain MRI scans, which were analyzed with voxel-based morphometry and tract based spatial statistics. In pathological gamblers, widespread lower white matter integrity (lower fractional anisotropy, higher mean diffusivity) was seen in multiple brain regions including the corpus callosum, the cingulum, the superior longitudinal fascicle, the inferior fronto-occipital fascicle, the anterior limb of internal capsule, the anterior thalamic radiation, the inferior longitudinal fascicle and the uncinate/inferior fronto-occipital fascicle. There were no volumetric differences in gray or white matter between pathological gamblers and controls. The results suggest that pathological gambling is associated with extensive lower integrity of several brain white matter tracts. The diffusion abnormality closely resembles previous findings in individuals with substance addictions.

  5. 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

  6. 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.

  7. 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.

  8. Analysis of supratentorial cystic abnormalities using in utero MR imaging

    PubMed Central

    Warner, Hannah M

    2016-01-01

    Objective: Our anecdotal experience from foetal neuroimaging studies suggests that there are often significant disagreements between the findings of ultrasonography (USS) and in utero MR (iuMR) imaging in cases of antenatally detected supratentorial extra-axial cysts. Although this is a relatively rare clinical situation, it warrants further investigation because of the high risk of other intracranial abnormalities that are likely to cause long-term neurodevelopmental problems. Methods: We reviewed 957 consecutive referrals for iuMR of the foetal brain over a 3.5-year period and studied all cases where the referral from USS described supratentorial extra-axial cysts in the foetus. The iuMR imaging was reviewed, and a comparison between the results of the two examinations was made. Results: Supratentorial extra-axial cysts were an unusual referral for iuMR occurring in only 13/957 (1.4%) of cases. The findings on USS and iuMR imaging were conflicting in all 13 cases with intracranial pathology being excluded on iuMR imaging in 4 cases and more significant pathology being shown in 9 cases. Abnormalities of the corpus callosum were recognized in association with a cyst in eight cases, and this was recognized in only two cases on USS. Six of those cases also had abnormalities of cortical formation. Conclusion: iuMR imaging should be used in the assessment of pregnancies in which a supratentorial extra-axial cyst has been detected on USS. This is based on the improved primary diagnosis and a high rate of associated brain abnormalities not detected on USS. Advances in knowledge: Our retrospective observational study examines a range of foetal intracranial abnormalities which are better defined using iuMRI. This is a previously described spectrum of neurodevelopmental anomalies which we suggest would benefit from MRI. PMID:26577541

  9. Neuroimaging abnormalities in clade C HIV are independent of Tat genetic diversity.

    PubMed

    Paul, Robert H; Phillips, Sarah; Hoare, Jacqueline; Laidlaw, David H; Cabeen, Ryan; Olbricht, Gayla R; Su, Yuqing; Stein, Dan J; Engelbrecht, Susan; Seedat, Soraya; Salminen, Lauren E; Baker, Laurie M; Heaps, Jodi; Joska, John

    2017-04-01

    Controversy remains regarding the neurotoxicity of clade C human immunodeficiency virus (HIV-C). When examined in preclinical studies, a cysteine to serine substitution in the C31 dicysteine motif of the HIV-C Tat protein (C31S) results in less severe brain injury compared to other viral clades. By contrast, patient cohort studies identify significant neuropsychological impairment among HIV-C individuals independent of Tat variability. The present study clarified this discrepancy by examining neuroimaging markers of brain integrity among HIV-C individuals with and without the Tat substitution. Thirty-seven HIV-C individuals with the Tat C31S substitution, 109 HIV-C individuals without the Tat substitution (C31C), and 34 HIV- controls underwent 3T structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). Volumes were determined for the caudate, putamen, thalamus, corpus callosum, total gray matter, and total white matter. DTI metrics included fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD). Tracts of interest included the anterior thalamic radiation (ATR), cingulum bundle (CING), uncinate fasciculus (UNC), and corpus callosum (CC). HIV+ individuals exhibited smaller volumes in subcortical gray matter, total gray matter and total white matter compared to HIV- controls. HIV+ individuals also exhibited DTI abnormalities across multiple tracts compared to HIV- controls. By contrast, neither volumetric nor diffusion indices differed significantly between the Tat C31S and C31C groups. Tat C31S status is not a sufficient biomarker of HIV-related brain integrity in patient populations. Clinical attention directed at brain health is warranted for all HIV+ individuals, independent of Tat C31S or clade C status.

  10. A structural abnormality associated with graded levels of ...

    EPA Pesticide Factsheets

    A large number of environmental contaminants reduce circulating levels of thyroid hormone (TH), but clear markers of neurological insult associated with modest TH insufficiency are lacking. We have previously identified the presence of an abnormal cluster of misplaced neurons in the corpus callosum (CC), a heterotopia, in adult rats following hypothyroidism induced by the hormone synthesis inhibitor, propylthiouracil (PTU). In this report we have investigated the dose- response relationships to administered dose of PTU, the magnitude of reductions in circulating TH, and the incidence and volume of the heterotopia in adult offspring of PTU-treated dams. Pregnant rat dams were administered 0, 1, 2, 3 or 10 ppm of PTU in the drinking water from gestational day 6 until pups were weaned on postnatal day 21 (PN2 1). Serum hormones in the dams were reduced in a dose-dependent manner, but at the lower dose levels (1, 2 and 3ppm) reductions were limited to T4 with no change in serum T3. At higher PTU concentrations, serum T3 was reduced in dams (1 Oppm) and pups on PN14 and 21 (3 and 10 ppm). All hormone levels returned to control levels in adulthood. On PN 130, female offspring were perfused with paraformaldehyde and sections prepared for immunohistochemistry for the neuron-specific antibody NeuN. All sections (40-45 50u through the hippocampus) were examined for the presence of a heterotopia in the CC. A dose-dependent increase in incidence and volume of heterotopic re

  11. 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.

  12. 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

  13. 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...

  14. 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…

  15. 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...

  16. 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)…

  17. 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…

  18. "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,…

  19. 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.

  20. 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.

  1. Developing Software for Corpus Research

    ERIC Educational Resources Information Center

    Mason, Oliver

    2008-01-01

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

  2. Specific MRI Abnormalities Reveal Severe Perrault Syndrome due to CLPP Defects

    PubMed Central

    Theunissen, Tom E. J.; Szklarczyk, Radek; Gerards, Mike; Hellebrekers, Debby M. E. I.; Mulder-Den Hartog, Elvira N. M.; Vanoevelen, Jo; Kamps, Rick; de Koning, Bart; Rutledge, S. Lane; Schmitt-Mechelke, Thomas; van Berkel, Carola G. M.; van der Knaap, Marjo S.; de Coo, Irenaeus F. M.; Smeets, Hubert J. M.

    2016-01-01

    In establishing a genetic diagnosis in heterogeneous neurological disease, clinical characterization and whole exome sequencing (WES) go hand-in-hand. Clinical data are essential, not only to guide WES variant selection and define the clinical severity of a genetic defect but also to identify other patients with defects in the same gene. In an infant patient with sensorineural hearing loss, psychomotor retardation, and epilepsy, WES resulted in identification of a novel homozygous CLPP frameshift mutation (c.21delA). Based on the gene defect and clinical symptoms, the diagnosis Perrault syndrome type 3 (PRLTS3) was established. The patient’s brain-MRI revealed specific abnormalities of the subcortical and deep cerebral white matter and the middle blade of the corpus callosum, which was used to identify similar patients in the Amsterdam brain-MRI database, containing over 3000 unclassified leukoencephalopathy cases. In three unrelated patients with similar MRI abnormalities the CLPP gene was sequenced, and in two of them novel missense mutations were identified together with a large deletion that covered part of the CLPP gene on the other allele. The severe neurological and MRI abnormalities in these young patients were due to the drastic impact of the CLPP mutations, correlating with the variation in clinical manifestations among previously reported patients. Our data show that similarity in brain-MRI patterns can be used to identify novel PRLTS3 patients, especially during early disease stages, when only part of the disease manifestations are present. This seems especially applicable to the severely affected cases in which CLPP function is drastically affected and MRI abnormalities are pronounced. PMID:27899912

  3. Congenital Abnormalities

    MedlinePlus

    ... Listen Español Text Size Email Print Share Congenital Abnormalities Page Content Article Body About 3% to 4% ... of congenital abnormalities earlier. 5 Categories of Congenital Abnormalities Chromosome Abnormalities Chromosomes are structures that carry genetic ...

  4. White-matter tract abnormalities and antisocial behavior: A systematic review of diffusion tensor imaging studies across development.

    PubMed

    Waller, Rebecca; Dotterer, Hailey L; Murray, Laura; Maxwell, Andrea M; Hyde, Luke W

    2017-01-01

    Antisocial behavior (AB), including aggression, violence, and theft, is thought be underpinned by abnormal functioning in networks of the brain critical to emotion processing, behavioral control, and reward-related learning. To better understand the abnormal functioning of these networks, research has begun to investigate the structural connections between brain regions implicated in AB using diffusion tensor imaging (DTI), which assesses white-matter tract microstructure. This systematic review integrates findings from 22 studies that examined the relationship between white-matter microstructure and AB across development. In contrast to a prior hypothesis that AB is associated with greater diffusivity specifically in the uncinate fasciculus, findings suggest that adult AB is associated with greater diffusivity across a range of white-matter tracts, including the uncinate fasciculus, inferior fronto-occipital fasciculus, cingulum, corticospinal tract, thalamic radiations, and corpus callosum. The pattern of findings among youth studies was inconclusive with both higher and lower diffusivity found across association, commissural, and projection and thalamic tracts.

  5. Extensive White Matter Abnormalities in Patients with First-Episode Schizophrenia: A Diffusion Tensor Imaging (DTI) Study

    PubMed Central

    Lee, Sang-Hyuk; Kubicki, Marek; Asami, Takeshi; Seidman, Larry J.; Goldstein, Jill M.; Mesholam-Gately, Raquelle I.; McCarley, Robert W.; Shenton, Martha E.

    2013-01-01

    Background Previous voxelwise Diffusion Tensor Imaging (DTI) investigations of white matter in first-episode schizophrenia (FESZ) have been limited to the analysis of Fractional Anisotropy (FA) and mean diffusivity (MD), with their findings inconsistent in terms of the anatomical locations and extent of abnormalities. This study examines white matter abnormalities in FESZ, compared with healthy controls, using a tract-based spatial statistics (TBSS) approach applied to multiple measures of tract integrity, and correlates these findings with symptom severity. Methods Seventeen first-episode patients with schizophrenia and seventeen age- and gender-matched healthy controls (HC) participated in this imaging study where FA, MD, and axial and radial diffusivity were compared between the two groups using TBSS. Results First-episode patients with schizophrenia showed lower FA values in the genu and body of corpus callosum, the internal capsule, the external capsule, the fornix, the superior, inferior fronto-occipital fasciculus, the cingulum, and the uncinate fasciculus compared with HC. Increased MD and radial diffusivity were shown in virtually all white matter regions. There was no significant difference, however, observed for axial diffusivity between the two groups. Pearson correlation analysis showed that the FA values of the right inferior fronto-occipital fasciculus were positively correlated with positive symptoms, negative symptoms, and total correct items of the Wisconsin Card Sorting Test. FA values of right external capsule also showed significant positive correlation with category completed scores of the WCST. Conclusions These data suggest extensive, possibly myelin related white matter disruptions in FESZ. PMID:23290268

  6. 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.

  7. Exploratory analysis of diffusion tensor imaging in children with attention deficit hyperactivity disorder: evidence of abnormal white matter structure.

    PubMed

    Pastura, Giuseppe; Doering, Thomas; Gasparetto, Emerson Leandro; Mattos, Paulo; Araújo, Alexandra Prüfer

    2016-06-01

    Abnormalities in the white matter microstructure of the attentional system have been implicated in the aetiology of attention deficit hyperactivity disorder (ADHD). Diffusion tensor imaging (DTI) is a promising magnetic resonance imaging (MRI) technology that has increasingly been used in studies of white matter microstructure in the brain. The main objective of this work was to perform an exploratory analysis of white matter tracts in a sample of children with ADHD versus typically developing children (TDC). For this purpose, 13 drug-naive children with ADHD of both genders underwent MRI using DTI acquisition methodology and tract-based spatial statistics. The results were compared to those of a sample of 14 age- and gender-matched TDC. Lower fractional anisotropy was observed in the splenium of the corpus callosum, right superior longitudinal fasciculus, bilateral retrolenticular part of the internal capsule, bilateral inferior fronto-occipital fasciculus, left external capsule and posterior thalamic radiation (including right optic radiation). We conclude that white matter tracts in attentional and motor control systems exhibited signs of abnormal microstructure in this sample of drug-naive children with ADHD.

  8. Microstructural White Matter Abnormalities and Cognitive Dysfunction in Subcortical Ischemic Vascular Disease: an Atlas-Based Diffusion Tensor Analysis Study.

    PubMed

    Lin, Lin; Xue, Yunjing; Duan, Qing; Sun, Bin; Lin, Hailong; Chen, Xiaodan; Luo, Ling; Wei, Xiaofan; Zhang, Zhongping

    2015-06-01

    Recent studies in subcortical ischemic vascular disease (SIVD) suggest the involvement of white matter (WM) abnormalities underlying the pathogenesis of cognitive function impairment. Here, we performed magnetic resonance diffusion tensor imaging (DTI) on detecting WM damage and to investigate the correlations between DTI measures and cognitive dysfunction in SIVD patients. Fifty right-handed SIVD patients were recruited and divided into vascular cognitive impairment on dementia (VCIND) group and normal cognition (NC) group. Twenty-two VCIND patients and 28 NC patients underwent DTI scanning and neuropsychological assessment. Atlas-based analysis (ABA) was performed on each subject for extracting FA and MD measures from supratentorial tracts. Among VCIND, as compared to NC patients, decreased FA and increased MD were observed in all projection fibers (bilateral anterior, posterior limb, and retrolenticular part of internal capsule, anterior, superior, and posterior corona radiata and posterior thalamic radiation), association fibers (bilateral sagittal stratum, external capsule, cingulum, fornix, and stria terminalis, superior longitudinal fasciculus, superior fronto-occipital fasciculus, and uncinate fasciculus), and commissural fibers (genu, body, splenium, and bilateral tapetum of corpus callosum). Furthermore, we also found that MoCA scores correlated with DTI values in all supratentorial WM tracts. The results suggested that SIVD patients demonstrated abnormal WM connectivity in all supratentorial regions. Moreover, the severity of damage in WM tracts correlated with cognitive dysfunction.

  9. 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…

  10. Contribution of Gray and White Matter Abnormalities to Cognitive Impairment in Multiple Sclerosis

    PubMed Central

    Zhang, Xiaofei; Zhang, Fangfang; Huang, Dehui; Wu, Lei; Ma, Lin; Liu, Hua; Zhao, Yujun; Yu, Shengyuan; Shi, Jiong

    2016-01-01

    Patients with multiple sclerosis (MS) commonly exhibit cognitive impairments (CI). However, the neural mechanisms underlying CI remain unclear. The current study applied diffusion tensor imaging (DTI) and voxel-based morphometric (VBM) magnetic resonance imaging (MRI) techniques to evaluate differences in white matter (WM) integrity and gray matter (GM) volume between MS patients with CI and MS patients with cognitive preservation (CP). Neuropsychological assessment and MRI were obtained from 39 relapsing-remitting MS (RRMS) patients and 29 healthy controls (HCs). Patients were classified as CI or CP according to cognitive ability, and demographic characteristics and MRI images were compared. Compared with HCs, MS patients exhibited widespread damage in WM integrity, and GM loss in several regions. Compared with CP patients, CI patients exhibited more extensive WM impairments, particularly in the corpus callosum, cerebellar peduncle, corona radiata, optic radiation, superior longitudinal fasciculus, anterior limb of the internal capsule, and cingulate, as well as decreased GM volume in the bilateral caudate, left insula and right temporal lobe. MS patients with CI exhibited more significant structural abnormalities than those with CP. Widespread impairments of WM integrity and selective GM atrophy both appear to be associated with impaired cognition in RRMS. PMID:28035997

  11. [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

  12. 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.

  13. Corpus Refactoring: a Feasibility Study

    PubMed Central

    Johnson, Helen L; Baumgartner, William A; Krallinger, Martin; Cohen, K Bretonnel; Hunter, Lawrence

    2007-01-01

    Background Most biomedical corpora have not been used outside of the lab that created them, despite the fact that the availability of the gold-standard evaluation data that they provide is one of the rate-limiting factors for the progress of biomedical text mining. Data suggest that one major factor affecting the use of a corpus outside of its home laboratory is the format in which it is distributed. This paper tests the hypothesis that corpus refactoring – changing the format of a corpus without altering its semantics – is a feasible goal, namely that it can be accomplished with a semi-automatable process and in a time-effcient way. We used simple text processing methods and limited human validation to convert the Protein Design Group corpus into two new formats: WordFreak and embedded XML. We tracked the total time expended and the success rates of the automated steps. Results The refactored corpus is available for download at the BioNLP SourceForge website http://bionlp.sourceforge.net. The total time expended was just over three person-weeks, consisting of about 102 hours of programming time (much of which is one-time development cost) and 20 hours of manual validation of automatic outputs. Additionally, the steps required to refactor any corpus are presented. Conclusion We conclude that refactoring of publicly available corpora is a technically and economically feasible method for increasing the usage of data already available for evaluating biomedical language processing systems. PMID:17854502

  14. 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.

  15. Characterization of subtle brain abnormalities in a mouse model of Hedgehog pathway antagonist-induced cleft lip and palate.

    PubMed

    Lipinski, Robert J; Holloway, Hunter T; O'Leary-Moore, Shonagh K; Ament, Jacob J; Pecevich, Stephen J; Cofer, Gary P; Budin, Francois; Everson, Joshua L; Johnson, G Allan; Sulik, Kathleen K

    2014-01-01

    Subtle behavioral and cognitive deficits have been documented in patient cohorts with orofacial clefts (OFCs). Recent neuroimaging studies argue that these traits are associated with structural brain abnormalities but have been limited to adolescent and adult populations where brain plasticity during infancy and childhood may be a confounding factor. Here, we employed high resolution magnetic resonance microscopy to examine primary brain morphology in a mouse model of OFCs. Transient in utero exposure to the Hedgehog (Hh) signaling pathway antagonist cyclopamine resulted in a spectrum of facial dysmorphology, including unilateral and bilateral cleft lip and palate, cleft of the secondary palate only, and a non-cleft phenotype marked by midfacial hypoplasia. Relative to controls, cyclopamine-exposed fetuses exhibited volumetric differences in several brain regions, including hypoplasia of the pituitary gland and olfactory bulbs, hyperplasia of the forebrain septal region, and expansion of the third ventricle. However, in affected fetuses the corpus callosum was intact and normal division of the forebrain was observed. This argues that temporally-specific Hh signaling perturbation can result in typical appearing OFCs in the absence of holoprosencephaly--a condition classically associated with Hh pathway inhibition and frequently co-occurring with OFCs. Supporting the premise that some forms of OFCs co-occur with subtle brain malformations, these results provide a possible ontological basis for traits identified in clinical populations. They also argue in favor of future investigations into genetic and/or environmental modulation of the Hh pathway in the etiopathogenesis of orofacial clefting.

  16. Characterization of Subtle Brain Abnormalities in a Mouse Model of Hedgehog Pathway Antagonist-Induced Cleft Lip and Palate

    PubMed Central

    Lipinski, Robert J.; Holloway, Hunter T.; O'Leary-Moore, Shonagh K.; Ament, Jacob J.; Pecevich, Stephen J.; Cofer, Gary P.; Budin, Francois; Everson, Joshua L.; Johnson, G. Allan; Sulik, Kathleen K.

    2014-01-01

    Subtle behavioral and cognitive deficits have been documented in patient cohorts with orofacial clefts (OFCs). Recent neuroimaging studies argue that these traits are associated with structural brain abnormalities but have been limited to adolescent and adult populations where brain plasticity during infancy and childhood may be a confounding factor. Here, we employed high resolution magnetic resonance microscopy to examine primary brain morphology in a mouse model of OFCs. Transient in utero exposure to the Hedgehog (Hh) signaling pathway antagonist cyclopamine resulted in a spectrum of facial dysmorphology, including unilateral and bilateral cleft lip and palate, cleft of the secondary palate only, and a non-cleft phenotype marked by midfacial hypoplasia. Relative to controls, cyclopamine-exposed fetuses exhibited volumetric differences in several brain regions, including hypoplasia of the pituitary gland and olfactory bulbs, hyperplasia of the forebrain septal region, and expansion of the third ventricle. However, in affected fetuses the corpus callosum was intact and normal division of the forebrain was observed. This argues that temporally-specific Hh signaling perturbation can result in typical appearing OFCs in the absence of holoprosencephaly—a condition classically associated with Hh pathway inhibition and frequently co-occurring with OFCs. Supporting the premise that some forms of OFCs co-occur with subtle brain malformations, these results provide a possible ontological basis for traits identified in clinical populations. They also argue in favor of future investigations into genetic and/or environmental modulation of the Hh pathway in the etiopathogenesis of orofacial clefting. PMID:25047453

  17. Alveolar abnormalities

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/001093.htm Alveolar abnormalities To use the sharing features on this page, please enable JavaScript. Alveolar abnormalities are changes in the tiny air sacs in ...

  18. Nail abnormalities

    MedlinePlus

    Beau's lines; Fingernail abnormalities; Spoon nails; Onycholysis; Leukonychia; Koilonychia; Brittle nails ... 2012:chap 71. Zaiac MN, Walker A. Nail abnormalities associated with systemic pathologies. Clin Dermatol . 2013;31: ...

  19. 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.

  20. 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…

  1. 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.

  2. 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

  3. Channels of the corpus callosum. Evidence from simple reaction times to lateralized flashes in the normal and the split brain.

    PubMed

    Iacoboni, M; Zaidel, E

    1995-06-01

    We studied 75 normal subjects and three commissurotomized patients using unimanual simple reaction times to lateralized flashes as a behavioural estimate of interhemispheric transmission time. Three different versions of the paradigm were performed: (i) the basic task; (ii) a motor task, with an increased complexity of the motor response; and (iii) a visual task, with an increased complexity of the visual stimulus presentation. We tested two hypotheses. First, that the new versions of the simple reaction time task result in shifts in hemispheric specialization for processing motor output (indicated by a main effect of response hand) or visual input (indicated by a main effect of visual field) alone, without affecting callosal transmission. In that case normals and split brain patients would show no significant task by response hand by visual field interaction and no significant task by crossed-uncrossed difference interaction. Secondly, that the new versions of the task affect callosal transfer. In that case, normals, but not split brain patients, would show a significant task by response hand by visual field interaction and a significant task by crossed-uncrossed difference interaction. Results are consistent with the latter hypothesis, showing that the motor task significantly changed the response hand by visual field interaction and the crossed-uncrossed difference, but only in normal subjects, perhaps producing a switch in the callosal channel subserving the interhemispheric transfer.

  4. [Shearing injuries of parasagittal white matter, corpus callosum and basal ganglia: possible radiological evidences of hemiplegia in diffuse axonal injury].

    PubMed

    Masuzawa, H; Kubo, T; Kanazawa, I; Kamitani, H; Nakamura, N

    1997-08-01

    The relationship between spastic hemiplegia in diffuse axonal injury (DAI) and neuroradiological findings was studied in 100 cases. These cases were prospectively collected from the files of Automobile Insurance Rating Organization in Japan between 1993 from to 1996. Requirements for entry to this study were as follows: presence of initial unconsciousness after head injury without any lucid interval. Existence of CT scan or MRI film obtained within 12 hours of injury showing no significant mass effects, as well as follow-up CT scan or MRI film obtained more than 3 months after the injury. Psychosocial outcome was described both by the medical professional and the caregiver. The hemiplegia was rated severe, mild, or none. The outcome and diffuse ventriculomegaly were classified as reported by the authors previously. Spastic hemiplegia or quadriplegia was documented in the chronic stage in 63 cases, including 53 severe cases with difficulty in walking and 10 mild cases with only pyramidal signs detected. Chi-square analysis showed significant correlation between hemiplegia and the DAI outcome level or ventriculomegaly rating. Focal brain contusion was noticed in 33 cases, but did not correlate with the hemiplegia at all. Radiological findings included 25 cases of parasagittal white matter injury (gliding contusion), 20 cases of callosal injury, 19 cases of basal ganglionic region injury, 5 cases of brain-stem injury, and 3 cases of cerebellar injury. Chi-square analyses of hemiplegia and contralateral presence of these injuries were significant in the former three types of injury. Presence of at least one of these 3 lesions was defined as GCB injury. There were altogether 46 GCB injury cases which were significantly correlated with contralateral hemiplegia by chi-square analysis and by Spearman rank analysis. Partial correlation analysis with hemiplegia as the target variable indicated highly significant correlation only with GCB injury and outcome level. In conclusion, spastic hemiplegia in DAI is a manifestation of primary shear injury. Neuroradiological findings of GCB injury were statistically able to be significantly correlated with the presence of hemiplegia, and suggested pyramidal tract injury either at the corona radiata or the internal capsule level.

  5. 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…

  6. 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…

  7. 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...

  8. A study of neurosonogram abnormalities, clinical correlation with neurosonogram findings, and immediate outcome of high-risk neonates in Neonatal Intensive Care Unit

    PubMed Central

    Nagaraj, Niranjan; Berwal, Pramod Kumar; Srinivas, Anusha; Sehra, Ramnarayan; Swami, Sarika; Jeevaji, Prathyusha; Swami, Gotam; Choudary, Lokesh; Berwal, Ayush

    2016-01-01

    Background: Neonatal sonography of the brain is now an essential part of newborn care, particularly in high risk and unstable premature infants. Cranial ultrasound is the most available and easily repeatable imaging technique for the neonatal brain showing brain development and the most frequently occurring forms of cerebral injury in the preterm and terms. This study aims to assess the importance of cranial ultrasound as an investigatory modality for high-risk neonates and to find out the morphology of various cerebral lesions and correlate clinically. Methodology: An observational correlation clinical study was conducted at Sardar Patel Medical College, Bikaner involving 100 high-risk neonates admitted to Neonatal Intensive Care Unit (NICU) who was subjected to neurosonography on selected days as per protocol. Perinatal details were recorded, and clinical examination with appropriate investigations was done. The cranial ultrasound was done, and morphology of various findings was studied and recorded. Clinical correlation with cranial ultrasound findings and follow-up was done. Results: On cranial ultrasound, 38% of neonates had abnormal findings. Twelve percent of these had evidence of intracranial bleed, 13% periventricular echogenicity, 7% had ventriculomegaly, 2% had cerebral edema, and 1% had leukomalacia. Three neonates had findings suggestive of simple cyst in middle cranial fossa, agenesis of corpus callosum, and choroid plexus cyst. Conclusions: Cranial ultrasonography is the best point of care neuroimaging method available for high-risk neonates. It is critical as an investigatory modality in NICU and effectively documents morphology of cerebral damage. PMID:27857787

  9. 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

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

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-18

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation; HITS Triathlon; Corpus Christi Bayfront, Corpus Christi, TX AGENCY: Coast Guard, DHS. ACTION: Temporary Final rule. SUMMARY: The Coast Guard is establishing a temporary Special Local Regulation in the Corpus Christi Bayfront area...

  11. Leukocyte abnormalities.

    PubMed

    Gabig, T G

    1980-07-01

    Certain qualitative abnormalities in neutrophils and blood monocytes are associated with frequent, severe, and recurrent bacterial infections leading to fatal sepsis, while other qualitative defects demonstrated in vitro may have few or no clinical sequelae. These qualitative defects are discussed in terms of the specific functions of locomotion, phagocytosis, degranulation, and bacterial killing.

  12. Enhancing Writing Pedagogy with Learner Corpus Data

    ERIC Educational Resources Information Center

    Cotos, Elena

    2014-01-01

    Learner corpora have become prominent in language teaching and learning, enhancing data-driven learning (DDL) pedagogy by promoting "learning driven data" in the classroom. This study explores the potential of a local learner corpus by investigating the effects of two types of DDL activities, one relying on a native-speaker corpus (NSC)…

  13. 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…

  14. 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...

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

    PubMed

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

    2013-11-01

    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 14years 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.

  16. 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

  17. 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).

  18. 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.

  19. Growth and development of the corpus luteum.

    PubMed

    Reynolds, L P; Redmer, D A

    1999-01-01

    The mammalian corpus luteum, which plays a central role in the reproductive process because of its production of hormones such as progesterone, is an exceptionally dynamic organ. Growth and development of the corpus luteum are extremely rapid, and even when the corpus luteum is functionally mature cellular turnover remains high. Associated with this high rate of cell turnover, the mature corpus luteum receives the greatest blood supply per unit tissue of any organ, and also exhibits a relatively high metabolic rate. Central to the growth and development of the corpus luteum, therefore, is luteal vascular growth, which appears to be regulated primarily by the angiogenic growth factors, basic fibroblast growth factor and vascular endothelial growth factor. In addition, the corpus luteum is a complex tissue composed of parenchymal (small and large steroidogenic) and nonparenchymal (for example fibroblasts, vascular smooth muscle, pericytes and endothelial) cells. Recent studies evaluating the expression, location and regulation of gap junctions in the corpus luteum indicate an important role of gap junctional intercellular communication in the coordination of function among these diverse cell types during luteal growth and development. These studies will lead to an improved understanding not only of luteal function but also of tissue growth and development in general.

  20. 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

  1. [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.

  2. 32 CFR 516.20 - Habeas Corpus.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... any civil officer having authority to apprehend offenders under the laws of the United States or of... the nature of a writ of habeas corpus, the SJA or legal adviser will immediately report the matter...

  3. Corpus callosotomy in a patient with startle epilepsy.

    PubMed

    Gómez, Nicolás Garófalo; Hamad, Ana Paula; Marinho, Murilo; Tavares, Igor M; Carrete, Henrique; Caboclo, Luís Otávio; Yacubian, Elza Márcia; Centeno, Ricardo

    2013-03-01

    Startle epilepsy is a syndrome of reflex epilepsy in which the seizures are precipitated by a sudden and surprising, usually auditory, stimulus. We describe herein a girl who had been suffering with startle-induced seizures since 2 years of age. She had focal, tonic and tonic-clonic seizures, refractory to antiepileptic treatment. Daily tonic seizures led to very frequent falls and morbidity. Neurologically, she had no deficit. Interictal EEG showed slow waves and epileptiform discharges in central and fronto-central regions. Video-polygraphic recordings of seizures, triggered by stimuli, showed generalised symmetric tonic posturing with ictal EEG, characterised by an abrupt and diffuse electrodecremental pattern of fast activity, followed by alpha-theta rhythm superimposed by epileptic discharges predominantly over the vertex and anterior regions. Magnetic resonance imaging showed no abnormalities. Corpus callosotomy was performed when the patient was 17. Since surgery, the patient (one year follow-up) has remained seizure-free. Corpus callosotomy may be considered in patients with startle epilepsy and tonic seizures, in the absence of focal lesions amenable to surgery. [Published with video sequences].

  4. 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…

  5. Callosal microstructural abnormalities in Alzheimer's disease and alcoholism: same phenotype, different mechanisms.

    PubMed

    Pitel, Anne-Lise; Chanraud, Sandra; Sullivan, Edith V; Pfefferbaum, Adolf

    2010-10-30

    Magnetic resonance (MRI) and diffusion tensor imaging (DTI) data were acquired in 13 Alzheimer's disease (AD) patients, 15 elderly alcoholics, and 32 elderly controls. Midsagittal area, length, dorsoventral height, fractional anisotropy (FA), and mean diffusivity (MD) of the total corpus callosum and volume of the lateral ventricles were measured; area, FA, and MD were also determined for the callosal genu, body, and splenium. On DTI, both patient groups had lower FA and higher MD than controls in all callosal regions. On MRI, both patient groups had smaller genu than controls; additional size deficits were present in the alcoholism group's callosal body and the AD group's splenium. The callosal arch was higher in the AD but not the alcoholic group compared with controls. The two patient groups had larger ventricles than controls, and the AD group had larger ventricles than the alcoholic group. Callosal area correlated with its height, and callosal FA and MD correlated with ventricular volume in AD, whereas callosal area correlated only with FA in alcoholics. In AD, the disruption of the callosal integrity, which was associated with distorted callosal shape, was related to ventricular dilation, which has been shown in twin studies to be under a multitude of genetic, polygenetic, and environmental influences. Conversely, in alcoholism, disruption of callosal microstructural integrity was related to shrinkage of the corpus callosum itself.

  6. 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...

  7. Volatiles emitted from single flower buds of the lilium longiflorum × L. callosum interspecific hybrid and its parents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This research was initiated to analyze the volatiles emitted from a single flower bud of Lilium longiflorum Thunb., L. callosum Sieb. et Zucc., and interspecific hybrids of L. longiflorum × L. callosum (L. longi × L. cal IH). Volatiles, collected automatically every 6-hour intervals at 20oC before ...

  8. 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.

  9. 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…

  10. 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…

  11. 33 CFR 165.808 - Corpus Christi Ship Channel, Corpus Christi, TX, safety zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Petroleum Gas, the waters within a 500 yard radius of the LPG carrier while the vessel transits the Corpus... within a 500 yard radius of the LPG carrier while the vessel departs the LPG facility and transits...

  12. 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…

  13. Imaging spectrum of pediatric corpus callosal pathology: a pictorial review.

    PubMed

    Hyun Yoo, Jeong; Hunter, Jill

    2013-04-01

    A wide spectrum of pediatric corpus callosal diseases can occur in the pediatric age group. Cross-sectional magnetic resonance imaging plays an important role in the diagnosis of these patients. We reviewed our imaging record and collected cases of corpus callosal pathology. The purpose of this review is to illustrate the imaging features of various corpus callosal lesions encountered in children.

  14. 33 CFR 110.75 - Corpus Christi Bay, Tex.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Corpus Christi Bay, Tex. 110.75... ANCHORAGE REGULATIONS Special Anchorage Areas § 110.75 Corpus Christi Bay, Tex. (a) South area. Southward of... said breakwater; and eastward of the Corpus Christi sea wall....

  15. 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…

  16. 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;…

  17. Developing a Disease Outbreak Event Corpus

    PubMed Central

    Kawazoe, Ai; Chanlekha, Hutchatai; Collier, Nigel

    2010-01-01

    Background In recent years, there has been a growth in work on the use of information extraction technologies for tracking disease outbreaks from online news texts, yet publicly available evaluation standards (and associated resources) for this new area of research have been noticeably lacking. Objective This study seeks to create a “gold standard” data set against which to test how accurately disease outbreak information extraction systems can identify the semantics of disease outbreak events. Additionally, we hope that the provision of an annotation scheme (and associated corpus) to the community will encourage open evaluation in this new and growing application area. Methods We developed an annotation scheme for identifying infectious disease outbreak events in news texts. An event─in the context of our annotation scheme─consists minimally of geographical (eg, country and province) and disease name information. However, the scheme also allows for the rich encoding of other domain salient concepts (eg, international travel, species, and food contamination). Results The work resulted in a 200-document corpus of event-annotated disease outbreak reports that can be used to evaluate the accuracy of event detection algorithms (in this case, for the BioCaster biosurveillance online news information extraction system). In the 200 documents, 394 distinct events were identified (mean 1.97 events per document, range 0-25 events per document). We also provide a download script and graphical user interface (GUI)-based event browsing software to facilitate corpus exploration. Conclusion In summary, we present an annotation scheme and corpus that can be used in the evaluation of disease outbreak event extraction algorithms. The annotation scheme and corpus were designed both with the particular evaluation requirements of the BioCaster system in mind as well as the wider need for further evaluation resources in this growing research area. PMID:20876049

  18. Clinics in diagnostic imaging (175)

    PubMed Central

    Krishnan, Vijay; Lim, Tze Chwan; Ho, Francis Cho Hao; Peh, Wilfred CG

    2017-01-01

    A 54-year-old man presented with change in behaviour, nocturnal enuresis, abnormal limb movement and headache of one week’s duration. The diagnosis of butterfly glioma (glioblastoma multiforme) was made based on imaging characteristics and was further confirmed by biopsy findings. As the corpus callosum is usually resistant to infiltration by tumours, a mass that involves and crosses the corpus callosum is suggestive of an aggressive neoplasm. Other neoplastic and non-neoplastic conditions that may involve the corpus callosum and mimic a butterfly glioma, as well as associated imaging features, are discussed. PMID:28361164

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

    PubMed

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

    2015-12-01

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

  20. 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

  1. PDGFR Inhibition Results in Pericyte Depletion and Hemorrhage into the Corpus Luteum of the Rat Ovary.

    PubMed

    Hall, Anthony P; Ashton, Susan; Horner, Judith; Wilson, Zena; Reens, Jaimini; Richmond, Graham H P; Barry, Simon T; Wedge, Steve R

    2016-01-01

    The growth plate, ovary, adrenal gland, and rodent incisor tooth are sentinel organs for antiangiogenic effects since they respond reliably, quantitatively, and sensitively to inhibition of the vascular endothelial growth factor receptor (VEGFR). Here we report that treatment of rats with platelet-derived growth factor receptor beta (PDGFRβ) inhibitors that target pericytes results in severe ovarian hemorrhage with degeneration and eventual rupture of the corpus luteum. Evaluation of the growth plate, adrenal gland, and incisor tooth that are typical target organs for antiangiogenic treatment in the rodent revealed no abnormalities. Histologically, the changes in the ovary were characterized by sinusoidal dilatation, increased vessel fragility, and hemorrhage into the corpus luteum. Immunocytochemical staining of vessels with alpha smooth muscle actin and CD31 that recognize pericytes and vascular endothelium, respectively, demonstrated that this effect was due to selective pericyte deficiency within corpora lutea. Further experiments in which rats were treated concurrently with both PDGFRβ and VEGFR inhibitors ablated the hemorrhagic response, resulting instead in corpus luteum necrosis. These changes are consistent with the notion that selective pericyte loss in the primitive capillary network resulted in increased vessel fragility and hemorrhage, whereas concomitant VEGFR inhibition resulted in vessel regression and reduced vascular perfusion that restricted development of the hemorrhagic vessels. These results also highlight the utility of the rodent ovary to respond differentially to VEGFR and PDGFR inhibitors, which may provide useful information during routine safety assessment for determining target organ toxicity.

  2. The Ubuntu Chat Corpus for Multiparticipant Chat Analysis

    DTIC Science & Technology

    2013-03-01

    as well as support in non- English languages . All messages are logged and kept in a public archive at http://irclogs.ubuntu.com/. We created a corpus...seen in a non-technical chat channel. Finally, the corpus contains channels in languages other than English , yet the channels cover the same general...with most fo- cusing on English . This corpus provides a great resource for investigating techniques on non- English languages and for investigating

  3. What's In a Note: Construction of a Suicide Note Corpus.

    PubMed

    Pestian, John P; Matykiewicz, Pawel; Linn-Gust, Michelle

    2012-01-01

    This paper reports on the results of an initiative to create and annotate a corpus of suicide notes that can be used for machine learning. Ultimately, the corpus included 1,278 notes that were written by someone who died by suicide. Each note was reviewed by at least three annotators who mapped words or sentences to a schema of emotions. This corpus has already been used for extensive scientific research.

  4. Urine - abnormal color

    MedlinePlus

    ... medlineplus.gov/ency/article/003139.htm Urine - abnormal color To use the sharing features on this page, please enable JavaScript. The usual color of urine is straw-yellow. Abnormally colored urine ...

  5. Tooth - abnormal colors

    MedlinePlus

    ... medlineplus.gov/ency/article/003065.htm Tooth - abnormal colors To use the sharing features on this page, please enable JavaScript. Abnormal tooth color is any color other than white to yellowish- ...

  6. Abnormal Head Position

    MedlinePlus

    ... cause. Can a longstanding head turn lead to any permanent problems? Yes, a significant abnormal head posture could cause permanent ... occipitocervical synostosis and unilateral hearing loss. Are there any ... postures? Yes. Abnormal head postures can usually be improved depending ...

  7. Skeletal limb abnormalities

    MedlinePlus

    ... medlineplus.gov/ency/article/003170.htm Skeletal limb abnormalities To use the sharing features on this page, please enable JavaScript. Skeletal limb abnormalities refers to a variety of bone structure problems ...

  8. 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

  9. 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…

  10. Functional consequences of a section of the anterior part of the body of the corpus callosum: evidence from an interhemispheric transcallosal approach.

    PubMed

    Peltier, Johann; Roussel, Martine; Gerard, Yasmina; Lassonde, Maryse; Deramond, Hervé; Le Gars, Daniel; Gars, Daniel Le; De Beaumont, Louis; Beaumont, Louis De; Godefroy, Olivier

    2012-09-01

    The aim of this study was to determine the neuropsychological consequences of a middle interhemispheric approach for the removal of tumors of the third or lateral ventricles. A retrospective analysis of eight callosotomized patients for ventricular tumors (three males/five females; mean age: 48.7 ± 11.2 years; education level: 11.9 ± 2.9 years) and eight healthy subjects was performed. An extensive neuropsychological test battery was used to evaluate global intellectual efficiency, memory capacities, executive functions, and interhemispheric transfer of a procedural learning task (serial reaction time task/SRTT). Neuropsychological results showed that: (1) five of eight patients operated through a middle transcallosal approach had disturbances of verbal or visual memory; (2) three of eight patients displayed a dysexecutive cognitive syndrome(two of eight of whom presenting with a deficit of verbal fluency); (3) two of eight patients presented a dysexecutive behavior syndrome; and (4) with regard to the SRTT, although all participants learned the task, in contrast to controls, the callosotomized patients showed an increase in reaction times and an absence of interhemispheric transfer of learning from one hand to the other. The transcallosal approach transects a large number of callosal fibers. This damage accounts for the deficits of memory, the dysexecutive cognitive and behavioral syndrome, and disturbances in interhemispheric transfer of learning.

  11. Corpus cavernosum abscess after Winter procedure performance

    PubMed Central

    Paladino, Joao Roberto; Nascimento, Fabio Jose; Gromatsky, Celso; Pompeo, Antonio Carlos Lima

    2014-01-01

    A 23-year-old male patient with sickle-cell disease reported his third episode of priapism complicated by the presence of a corpus cavernosum abscess after the performance of a Winter procedure 20 days prior to his presentation. While in hospital for 11 days, two penile needle aspirations and three surgical drainages were performed with associated antibiotic therapy. He evolved with erectile dysfunction refractory to drug therapy and his infectious condition improved. An early penile prosthesis implantation followed after the use of a vacuum pump in an attempt to decrease the fibrotic process of the corpora cavernosa. Final results were positive. PMID:24515231

  12. An unknown combination of infantile spasms, retinal lesions, facial dysmorphism and limb abnormalities.

    PubMed

    Plomp, A S; Reardon, W; Benton, S; Taylor, D; Larcher, V F; Sundrum, R; Winter, R M

    2000-07-01

    A female patient is presented with infantile spasms, punched-out retinal lesions, facial dysmorphism, short upper arms, short thumbs, left lower limb hypoplasia with foot deformity, a hemivertebra, atrial septal defect, growth retardation and severe developmental delay. There is some similarity to patients with Aicardi syndrome (AS), but the retinal lesions in our patient are different and she does not have agenesis of the corpus callosum, one of the diagnostic features of AS. She might represent an atypical form of this syndrome with additional features, usually not present in AS. As there is no diagnostic test for AS yet, this diagnosis cannot be confirmed nor rejected with certainty. However, it might be more likely that our patient has another, possibly unique, condition.

  13. 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…

  14. Abnormal Uterine Bleeding FAQ

    MedlinePlus

    ... PROBLEMS Abnormal Uterine Bleeding • What is a normal menstrual cycle? • When is bleeding abnormal? • At what ages is ... treat abnormal bleeding? •Glossary What is a normal menstrual cycle? The normal length of the menstrual cycle is ...

  15. The Use of a Corpus in Contrastive Studies.

    ERIC Educational Resources Information Center

    Filipovic, Rudolf

    1973-01-01

    Before beginning the Serbocroatian-English Contrastive Project, it was necessary to determine whether to base the analysis on a corpus or on native intuitions. It seemed that the best method would combine the theoretical and the empirical. A translation method based on a corpus of text was adopted. The Brown University "Standard Sample of…

  16. 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…

  17. 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…

  18. 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…

  19. 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,…

  20. 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,…

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

    PubMed

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

    2015-06-01

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

  2. 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)…

  3. 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...

  4. 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

  5. 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.

  6. 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

  7. 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.

  8. A corpus-linguistic investigation of dental English.

    PubMed

    Carlson, D M

    2000-04-01

    This article begins by presenting corpus linguistics and explaining how the corpus approach to language analysis can be used to investigate the language of dentistry. It then reports findings from an analysis that was carried out with readily available software and a corpus of 1,400 dental research abstracts. Included is information about word frequency in dental abstracts and also about how certain words tend to co-occur in sentences and form regular patterns. The article concludes with a discussion of ways that corpus-based findings can be applied to the teaching of English to non-native speakers of the language, many of whom will need English skills for their future careers in dentistry.

  9. RadNet Air Data From Corpus Christi, TX

    EPA Pesticide Factsheets

    This page presents radiation air monitoring and air filter analysis data for Corpus Christi, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.

  10. A massively parallel corpus: the Bible in 100 languages.

    PubMed

    Christodouloupoulos, Christos; Steedman, Mark

    We describe the creation of a massively parallel corpus based on 100 translations of the Bible. We discuss some of the difficulties in acquiring and processing the raw material as well as the potential of the Bible as a corpus for natural language processing. Finally we present a statistical analysis of the corpora collected and a detailed comparison between the English translation and other English corpora.

  11. Building a Large Annotated Corpus of English: The Penn Treebank

    DTIC Science & Technology

    1993-04-30

    Brill 1991]) or the skeletally parsed corpus ([Weischedel et al 1991], [Pereira and Schabes 1992]). The POS-tagged corpus has also been used to train a...Niv 1991] Niv, Michael, 1991. Syntactic disambiguation. In The Penn Review of Linguistics 14, pages 120-126. [Pereira and Schabes 1992] Pereira...Fernando and Schabes , Yves. 1992. Inside-outside reestimation from partially bracketed corpora. In Proceedings of the 30th Annual Meeting of the

  12. 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

  13. 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

  14. "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)

  15. 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

  16. 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.

  17. Human corpus luteum secretion of relaxin, oxytocin, and progesterone.

    PubMed

    Khan-Dawood, F S; Goldsmith, L T; Weiss, G; Dawood, M Y

    1989-03-01

    To determine whether the human corpus luteum is a source of relaxin and oxytocin, we measured the concentrations of these peptides in plasma obtained from the ovarian veins of ovaries with and without a corpus luteum and compared these to peripheral plasma levels. Peripheral and ovarian venous blood samples were obtained from 34 nonpregnant women, 13 during the luteal phase and 21 during the follicular phase of their cycles, and from a 6-week pregnant woman. Plasma relaxin, oxytocin, and progesterone concentrations were determined by sensitive and specific RIAs. Plasma relaxin levels were not detectable (less than 0.16 microgram/L) in peripheral or ovarian venous plasma not draining a corpus luteum. The mean relaxin concentration in plasma draining an ovary with a corpus luteum was 0.41 +/- 0.09 (+/- SE) microgram/L. Oxytocin levels also were significantly higher in plasma draining an ovary with a corpus luteum (6.70 +/- 1.86 pmol/L) than in that draining the ovary with no corpus luteum (1.58 +/- 0.09 pmol/L; P less than 0.01) or in peripheral plasma (1.58 +/- 0.09 pmol/L; P less than 0.025). The mean progesterone concentration also was highest in plasma draining an ovary with a corpus luteum (210.2 +/- 50.5 nmol/L) compared with those in plasma from the contralateral ovarian vein (40.3 +/- 16.5 nmol/L P less than 0.005) and peripheral plasma (30.2 +/- 5.7 nmol/L; P less than 0.005) during the luteal phase. In a woman who was 6 weeks pregnant, plasma draining the ovary with a corpus luteum had 1.9 micrograms relaxin/L, but only 0.49 pmol/L oxytocin; the latter was similar to concentrations in noncorpus luteum-bearing ovarian venous plasma. These findings indicate that the human corpus luteum secretes relaxin, oxytocin, and progesterone. Both ovarian oxytocin and relaxin may function as paracrine or autocrine modulators of luteal function.

  18. [The relativity of abnormity].

    PubMed

    Nilson, Annika

    2006-01-01

    In the late 19th century and in the beginning of the 20th century, mental diseases and abnormal behavior was considered to be a great danger to culture and society. "Degeneration" was the buzzword of the time, used and misused by artists and scientists alike. At the same time, some scientists saw abnormity as the key to unlock the mysteries of the ordinary mind. Naturalistic curiosity left Pandoras box open when religion declined in Darwins wake. Two swedish scientists, the physician Bror Gadelius (1862-1938) and his friend the philosopher Axel Herrlin (1870-1937), inspired by the French psychologist Theodule Ribots (1839-1916) "psychology without a soul", denied all fixed demarcation lines between abnormity and normality. All humans are natures creatures ruled by physiological laws, not ruled by God or convention. Even ordinary morality was considered to be an utterly backward explanation and guideline for complex human behavior. Different forms of therapy, not various kinds of penalties for wicked and disturbing behavior, are the now the solution for lots of people, "normal" as well as "abnormal". Psychiatry is expanding.

  19. Abnormalities of gonadal differentiation.

    PubMed

    Berkovitz, G D; Seeherunvong, T

    1998-04-01

    Gonadal differentiation involves a complex interplay of developmental pathways. The sex determining region Y (SRY) gene plays a key role in testis determination, but its interaction with other genes is less well understood. Abnormalities of gonadal differentiation result in a range of clinical problems. 46,XY complete gonadal dysgenesis is defined by an absence of testis determination. Subjects have female external genitalia and come to clinical attention because of delayed puberty. Individuals with 46,XY partial gonadal dysgenesis usually present in the newborn period for the valuation of ambiguous genitalia. Gonadal histology always shows an abnormality of seminiferous tubule formation. A diagnosis of 46,XY true hermaphroditism is made if the gonads contain well-formed testicular and ovarian elements. Despite the pivotal role of the SRY gene in testis development, mutations of SRY are unusual in subjects with a 46,XY karyotype and abnormal gonadal development. 46,XX maleness is defined by testis determination in an individual with a 46,XX karyotype. Most affected individuals have a phenotype similar to that of Klinefelter syndrome. In contrast, subjects with 46,XX true hermaphroditism usually present with ambiguous genitalia. The majority of subjects with 46,XX maleness have Y sequences including SRY in genomic DNA. However, only rare subjects with 46,XX true hermaphroditism have translocated sequences encoding SRY. Mosaicism and chimaerism involving the Y chromosome can also be associated with abnormal gonadal development. However, the vast majority of subjects with 45,X/46,XY mosaicism have normal testes and normal male external genitalia.

  20. Discourse and identity in a corpus of lesbian erotica.

    PubMed

    Morrish, Liz; Sauntson, Helen

    2011-01-01

    This article uses corpus linguistic methodologies to explore representations of lesbian desires and identities in a corpus of lesbian erotica from the 1980s and 1990s. We provide a critical examination of the ways in which "lesbian gender," power, and desire are represented, (re-)produced, and enacted, often in ways that challenge hegemonic discourses of gender and sexuality. By examining word frequencies and collocations, we critically analyze some of the themes, processes, and patterns of representation in the texts. Although rooted in linguistics, we hope this article provides an accessible, interdisciplinary, and timely contribution toward developing understandings of discursive practices surrounding gender and sexuality.

  1. 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.

  2. Heritable bovine fetal abnormalities.

    PubMed

    Whitlock, B K; Kaiser, L; Maxwell, H S

    2008-08-01

    The etiologies for congenital bovine fetal anomalies can be divided into heritable, toxic, nutritional, and infectious categories. Although uncommon in most herds, inherited congenital anomalies are probably present in all breeds of cattle and propagated as a result of specific trait selection that inadvertently results in propagation of the defect. In some herds, the occurrence of inherited anomalies has become frequent, and economically important. Anomalous traits can affect animals in a range of ways, some being lethal or requiring euthanasia on humane grounds, others altering structure, function, or performance of affected animals. Veterinary practitioners should be aware of the potential for inherited defects, and be prepared to investigate and report animals exhibiting abnormal characteristics. This review will discuss the morphologic characteristics, mode of inheritance, breeding lines affected, and the availability of genetic testing for selected heritable bovine fetal abnormalities.

  3. Liver abnormalities in pregnancy.

    PubMed

    Than, Nwe Ni; Neuberger, James

    2013-08-01

    Abnormalities of liver function (notably rise in alkaline phosphatase and fall in serum albumin) are common in normal pregnancy, whereas rise in serum bilirubin and aminotransferase suggest either exacerbation of underlying pre-existing liver disease, liver disease related to pregnancy or liver disease unrelated to pregnancy. Pregnant women appear to have a worse outcome when infected with Hepatitis E virus. Liver diseases associated with pregnancy include abnormalities associated hyperemesis gravidarum, acute fatty liver disease, pre-eclampsia, cholestasis of pregnancy and HELLP syndrome. Prompt investigation and diagnosis is important in ensuring a successful maternal and foetal outcome. In general, prompt delivery is the treatment of choice for acute fatty liver, pre-eclampsia and HELLP syndrome and ursodeoxycholic acid is used for cholestasis of pregnancy although it is not licenced for this indication.

  4. 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.

  5. 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

  6. [Molecular abnormalities in lymphomas].

    PubMed

    Delsol, G

    2010-11-01

    Numerous molecular abnormalities have been described in lymphomas. They are of diagnostic and prognostic value and are taken into account for the WHO classification of these tumors. They also shed some light on the underlying molecular mechanisms involved in lymphomas. Overall, four types of molecular abnormalities are involved: mutations, translocations, amplifications and deletions of tumor suppressor genes. Several techniques are available to detect these molecular anomalies: conventional cytogenetic analysis, multicolor FISH, CGH array or gene expression profiling using DNA microarrays. In some lymphomas, genetic abnormalities are responsible for the expression of an abnormal protein (e.g. tyrosine-kinase, transcription factor) detectable by immunohistochemistry. In the present review, molecular abnormalities observed in the most frequent B, T or NK cell lymphomas are discussed. In the broad spectrum of diffuse large B-cell lymphomas microarray analysis shows mostly two subgroups of tumors, one with gene expression signature corresponding to germinal center B-cell-like (GCB: CD10+, BCL6 [B-Cell Lymphoma 6]+, centerine+, MUM1-) and a subgroup expressing an activated B-cell-like signature (ABC: CD10-, BCL6-, centerine-, MUM1+). Among other B-cell lymphomas with well characterized molecular abnormalies are follicular lymphoma (BCL2 deregulation), MALT lymphoma (Mucosa Associated Lymphoid Tissue) [API2-MALT1 (mucosa-associated-lymphoid-tissue-lymphoma-translocation-gene1) fusion protein or deregulation BCL10, MALT1, FOXP1. MALT1 transcription factors], mantle cell lymphoma (cycline D1 [CCND1] overexpression) and Burkitt lymphoma (c-Myc expression). Except for ALK (anaplastic lymphoma kinase)-positive anaplastic large cell lymphoma, well characterized molecular anomalies are rare in lymphomas developed from T or NK cells. Peripheral T cell lymphomas not otherwise specified are a heterogeneous group of tumors with frequent but not recurrent molecular abnormalities

  7. Pharmacological characterization of adrenoceptors in horse corpus cavernosum penis.

    PubMed

    Recio, P; López, P G; Fernández, J L; Garcia-Sacristán, A

    1997-06-01

    1. The presence and types of alpha and beta-adrenoceptors in the corpus cavernosum of the horse were studied in vitro by using selected ligands of adrenoceptors and isometric tension recording. 2. Noradrenaline and phenylephrine induced concentration-dependent contractions in corpus cavernosum preparations. B-HT 920 had no effect. 3. Phentolamine and prazosin produced a shift to the right of the dose-response curve of noradrenaline, while the alpha(2)-antagonist, rauwolscine had no effect on the response to noradrenaline. Phenylephrine-evoked contractions of corporal strips were significantly inhibited by the alpha(1)-adrenoceptor antagonist, prazosin. 4. Isoprenaline and salbutamol each relaxed precontracted corpus cavernosum preparations in a concentration-dependent manner; the isoprenaline effect was blocked by propranolol, practolol and butoxamine. The salbutamol effect was blocked by butoxamine. 5. These results suggest that presence of postjunctional alpha(1)-adrenoceptors in horse corpus cavernosum. There is also a heterogenous population of beta-adrenoceptors in this tissue, belonging to the beta(1) and beta(2) subtypes.

  8. Corpus-Based Learning of Cantonese for Mandarin Speakers

    ERIC Educational Resources Information Center

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

    2016-01-01

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

  9. 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…

  10. 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…

  11. Modifying Corpus Annotation to Support the Analysis of Learner Language

    ERIC Educational Resources Information Center

    Dickinson, Markus; Lee, Chong Min

    2009-01-01

    A crucial question for automatically analyzing learner language is to determine which grammatical information is relevant and useful for learner feedback. Based on knowledge about how learner language varies in its grammatical properties, we propose a framework for reusing analyses found in corpus annotation and illustrate its applicability to…

  12. 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…

  13. 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…

  14. Combining text clustering and retrieval for corpus adaptation

    NASA Astrophysics Data System (ADS)

    He, Feng; Ding, Xiaoqing

    2007-01-01

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

  15. 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…

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

    ERIC Educational Resources Information Center

    De Cuypere, Ludovic; Verbeke, Saartje

    2013-01-01

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

  17. Learner Corpus Analysis and the Development of Foreign Language Proficiency

    ERIC Educational Resources Information Center

    Belz, Julie A.

    2004-01-01

    This paper makes a methodological contribution to the emerging field of learner corpus analysis [Granger, S., 1998. Learner English on Computer. Longman, London, 1998; Granger, S., 2002. Computer Learner corpora, Second Language Acquisition, and Foreign Language Teaching. John Benjamins, Amsterdam, 2002] and to Second Language Acquisition (SLA)…

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

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Corpus of estate; net worth. 3.263 Section 3.263 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION Pension, Compensation, and Dependency and Indemnity Compensation Dependency, Income and Estate §...

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

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Corpus of estate; net worth. 3.263 Section 3.263 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION Pension, Compensation, and Dependency and Indemnity Compensation Dependency, Income and Estate §...

  20. 38 CFR 3.263 - Corpus of estate; net worth.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Corpus of estate; net worth. 3.263 Section 3.263 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION Pension, Compensation, and Dependency and Indemnity Compensation Dependency, Income and Estate §...

  1. 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

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

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the corpus of estate of a parent where dependency is a factor under § 3.250, and the net worth of a....252(b). Only the estate of the parent, in claims based on dependency, or the estate of the veteran... all real and personal property owned by the claimant except the claimant's dwelling...

  3. 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…

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

    ERIC Educational Resources Information Center

    Nelson, Mike

    2006-01-01

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

  5. 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…

  6. 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…

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

    ERIC Educational Resources Information Center

    Heather, Julian; Helt, Marie

    2012-01-01

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

  8. 26 CFR 1.661(a)-1 - Estates and trusts accumulating income or distributing corpus; general.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... distributing corpus; general. 1.661(a)-1 Section 1.661(a)-1 Internal Revenue INTERNAL REVENUE SERVICE... Accumulate Income Or Which Distribute Corpus § 1.661(a)-1 Estates and trusts accumulating income or distributing corpus; general. Subpart C, part I, subchapter J, chapter 1 of the Code, is applicable to...

  9. 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…

  10. 76 FR 31821 - Amendment of Class D Airspace; Corpus Christi, TX

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-02

    ... Federal Aviation Administration 14 CFR Part 71 Amendment of Class D Airspace; Corpus Christi, TX AGENCY... amends Class D airspace within the Corpus Christi, TX, area by updating the geographic coordinates for... the geographic coordinates, within Class D airspace, of the Cabaniss NOLF, Corpus Christi, TX,...

  11. 76 FR 49285 - Amendment of Class D Airspace; Corpus Christi, TX

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ... Federal Aviation Administration 14 CFR Part 71 Amendment of Class D Airspace; Corpus Christi, TX AGENCY... Register June 2, 2011, ] amending Class D airspace at Cabaniss Navy Outlying Field (NOLF), Corpus Christi... Cabaniss NOLF, Corpus Christi, TX (76 FR 31821, Docket No. FAA-2010-1171). Subsequent to publication,...

  12. 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…

  13. 26 CFR 1.643(b)-2 - Dividends allocated to corpus.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Dividends allocated to corpus. 1.643(b)-2... to corpus. Extraordinary dividends or taxable stock dividends which the fiduciary, acting in good faith, determines to be allocable to corpus under the terms of the governing instrument and...

  14. 40 CFR 81.136 - Corpus Christi-Victoria Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Corpus Christi-Victoria Intrastate Air... Air Quality Control Regions § 81.136 Corpus Christi-Victoria Intrastate Air Quality Control Region. The Corpus Christi-Victoria Intrastate Air Quality Control Region (Texas) consists of the...

  15. 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.…

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

    PubMed

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

    2016-07-01

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

  17. 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 ...

  18. 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.

  19. 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…

  20. 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…

  1. Epilepsy and chromosomal abnormalities

    PubMed Central

    2010-01-01

    Background Many chromosomal abnormalities are associated with Central Nervous System (CNS) malformations and other neurological alterations, among which seizures and epilepsy. Some of these show a peculiar epileptic and EEG pattern. We describe some epileptic syndromes frequently reported in chromosomal disorders. Methods Detailed clinical assessment, electrophysiological studies, survey of the literature. Results In some of these congenital syndromes the clinical presentation and EEG anomalies seems to be quite typical, in others the manifestations appear aspecific and no strictly linked with the chromosomal imbalance. The onset of seizures is often during the neonatal period of the infancy. Conclusions A better characterization of the electro clinical patterns associated with specific chromosomal aberrations could give us a valuable key in the identification of epilepsy susceptibility of some chromosomal loci, using the new advances in molecular cytogenetics techniques - such as fluorescent in situ hybridization (FISH), subtelomeric analysis and CGH (comparative genomic hybridization) microarray. However further studies are needed to understand the mechanism of epilepsy associated with chromosomal abnormalities. PMID:20438626

  2. Skeletal abnormalities in homocystinuria.

    PubMed Central

    Brenton, D. P.

    1977-01-01

    The skeletal changes of thirty-four patients with the biochemical and clinical features of cystathionine synthase deficiency are described. It is emphasized that there is clinical evidence of excessive bone growth and the formation for bone which is structurally weaker than normal. The similarities and differences between this condition and Marfan's syndrome are stressed and the possible nature of the connective tissue defect leading to the skeletal changes discussed. The most characteristic skeletal changes in homocystinuria are the skeletal disproportion (pubis-heel length greater than crown-pubis length), the abnormal vertebrae, sternal deformities, genu valgum and large metaphyses and epiphyses. Images Fig. 2 Fig. 3 Fig. 4 Fig. 8 Fig. 9 Fig. 10 PMID:917963

  3. Eye movement abnormalities.

    PubMed

    Moncayo, Jorge; Bogousslavsky, Julien

    2012-01-01

    Generation and control of eye movements requires the participation of the cortex, basal ganglia, cerebellum and brainstem. The signals of this complex neural network finally converge on the ocular motoneurons of the brainstem. Infarct or hemorrhage at any level of the oculomotor system (though more frequent in the brain-stem) may give rise to a broad spectrum of eye movement abnormalities (EMAs). Consequently, neurologists and particularly stroke neurologists are routinely confronted with EMAs, some of which may be overlooked in the acute stroke setting and others that, when recognized, may have a high localizing value. The most complex EMAs are due to midbrain stroke. Horizontal gaze disorders, some of them manifesting unusual patterns, may occur in pontine stroke. Distinct varieties of nystagmus occur in cerebellar and medullary stroke. This review summarizes the most representative EMAs from the supratentorial level to the brainstem.

  4. 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

  5. Distinctive Phenotypic Abnormalities Associated with Submicroscopic 21q22 Deletion Including DYRK1A

    PubMed Central

    Oegema, R.; de Klein, A.; Verkerk, A.J.; Schot, R.; Dumee, B.; Douben, H.; Eussen, B.; Dubbel, L.; Poddighe, P.J.; van der Laar, I.; Dobyns, W.B.; van der Spek, P.J.; Lequin, M.H.; de Coo, I.F.M.; de Wit, M.-C.Y.; Wessels, M.W.; Mancini, G.M.S.

    2010-01-01

    Partial monosomy 21 has been reported, but the phenotypes described are variable with location and size of the deletion. We present 2 patients with a partially overlapping microdeletion of 21q22 and a striking phenotypic resemblance. They both presented with severe psychomotor delay, behavioral problems, no speech, microcephaly, feeding problems with frequent regurgitation, idiopathic thrombocytopenia, obesity, deep set eyes, down turned corners of the mouth, dysplastic ears, and small chin. Brain MRI showed cerebral atrophy mostly evident in frontal and temporal lobes, widened ventricles and thin corpus callosum in both cases, and in one patient evidence of a migration disorder. The first patient also presented with epilepsy and a ventricular septum defect. The second patient had a unilateral Peters anomaly. Microarray analysis showed a partially overlapping microdeletion spanning about 2.5 Mb in the 21q22.1–q22.2 region including the DYRK1A gene and excluding RUNX1. These patients present with a recognizable phenotype specific for this 21q22.1–q22.2 locus. We searched the literature for patients with overlapping deletions including the DYRK1A gene, in order to define other genes responsible for this presentation. PMID:21031080

  6. Anaphoric relations in the clinical narrative: corpus creation

    PubMed Central

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

    2011-01-01

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

  7. Localization of relaxin in human gestational corpus luteum.

    PubMed

    Mathieu, P; Rahier, J; Thomas, K

    1981-01-01

    Corpora lutea from 12 pregnant women were prepared for immunohistochemical localization of relaxin using a highly specific antiserum. A positive response is given by luteal cells that are diffusely distributed throughout the corpus luteum. These cells do not form a distinctive group in any particular area. A negative response is seen in the adjacent ovarian tissue, and also in nongestational corpora lutea in early luteal phase.

  8. The regulation of the human corpus luteum steroidogenesis: a hypothesis?

    PubMed

    Oon, V J; Johnson, M R

    2000-01-01

    The corpus luteum (CL) is an important endocrine organ in the menstrual cycle and in pregnancy. The regulation of its hormonal production has been extensively studied. The steroidogenic abilities of the CL can be rescued by human chorionic gonadotrophin (HCG) but its role in the maintenance of CL function is not clear. We will discuss the hypothesis that there are fetoplacental factors, other than HCG, that modulate CL steroidogenesis.

  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 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

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

    ERIC Educational Resources Information Center

    Flowerdew, L.

    2005-01-01

    In the past few years, several corpus-based studies have been carried out which either explicitly in some cases, but more subtly in others, draw on aspects of genre theory for their analyses. The purpose of this paper is to review those corpus studies which specifically draw on either the English for Specific Purposes (following the Swales…

  12. 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…

  13. The Effects of Utilizing Corpus Resources to Correct Collocation Errors in L2 Writing--Students' Performance, Corpus Use and Perceptions

    ERIC Educational Resources Information Center

    Wu, Yi-ju

    2016-01-01

    Data-Driven Learning (DDL), in which learners "confront [themselves] directly with the corpus data" (Johns, 2002, p. 108), has shown to be effective in collocation learning in L2 writing. Nevertheless, there have been only few research studies of this type examining the relationship between English proficiency and corpus consultation.…

  14. 33 CFR 334.800 - Corpus Christi Bay, Tex.; seaplane restricted area, U.S. Naval Air Station, Corpus Christi.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND... follows: Beginning at a point on the south shore of Corpus Christi Bay at the “North Gate” of the U.S...′41.6″ 97°15′33.3″ thence to a point on shore at latitude 27°40′44.9″ N.; thence along the shore...

  15. 33 CFR 334.800 - Corpus Christi Bay, Tex.; seaplane restricted area, U.S. Naval Air Station, Corpus Christi.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND... follows: Beginning at a point on the south shore of Corpus Christi Bay at the “North Gate” of the U.S...′41.6″ 97°15′33.3″ thence to a point on shore at latitude 27°40′44.9″ N.; thence along the shore...

  16. Temporary and permanent signs of interhemispheric disconnection after traumatic brain injury.

    PubMed

    Peru, Andrea; Beltramello, Alberto; Moro, Valentina; Sattibaldi, Lorenzo; Berlucchi, Giovanni

    2003-01-01

    The corpus callosum is frequently damaged by closed head traumas, and the resulting deficits of interhemispheric communication may vary according to the specific position of the lesion within the corpus callosum. This paper describes a single case who suffered a severe traumatic brain injury resulting in a lesion of the posterior body of the corpus callosum. Among the classical symptoms of interhemispheric disconnection, left hand anomia, left upper limb ideomotor dyspraxia, left visual field dyslexia and dysnomia, and left ear suppression in a dichotic listening task were observed shortly after the injury but recovered completely or almost completely with the passage of time. The only symptom of interhemispheric disconnection which was found to persist more than 4 years after the injury was an abnormal prolongation of the crossed-uncrossed difference in a simple visuomotor reaction time task. This prolongation was comparable with that observed in subjects with complete callosal lesions or agenesis. The results suggest that the posterior body of the corpus callosum may be an obligatory interhemispheric communication channel for mediating fast visuo-motor responses. The transient nature of other symptoms of interhemispheric disconnection suggests a relatively wide dispersion of fibers with different functions through the callosal body, such that parts of them can survive a restricted lesion and allow functional recovery of hemispheric interactions. An assessment of the evolution in time of symptoms of interhemispheric disconnection following restricted callosal lesions may reveal fine and coarse features of the anatomo-functional topography of the corpus callosum.

  17. 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.

  18. 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.

  19. 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

  20. Morphologic Response to a New Inlet, Packery Channel, Corpus Christi, Texas

    DTIC Science & Technology

    2007-01-01

    terminology, Aransas Pass (shared with Aransas Bay to the north) on the north side and Corpus Christi Pass on the south side, in the SSE corner (Fig...1 and Fig. 2). Dredging of Aransas Pass started in 1912, and its re-direction into Corpus Christi Bay in 1924 caused Corpus Christi Pass to slowly...rather than the 23-mile (37 km) transit to Aransas Pass. The North Padre Island (Packery Channel), Nueces County, Texas, Storm Damage Reduction

  1. What’s In a Note: Construction of a Suicide Note Corpus

    PubMed Central

    Pestian, John P.; Matykiewicz, Pawel; Linn-Gust, Michelle

    2012-01-01

    This paper reports on the results of an initiative to create and annotate a corpus of suicide notes that can be used for machine learning. Ultimately, the corpus included 1,278 notes that were written by someone who died by suicide. Each note was reviewed by at least three annotators who mapped words or sentences to a schema of emotions. This corpus has already been used for extensive scientific research. PMID:23170067

  2. 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

    ... 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. (a) Location. The following area is designated as a security zone: all waters of the Corpus Christi...

  3. 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…

  4. 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…

  5. Incontinentia Pigmenti

    DTIC Science & Technology

    2008-01-01

    deformities of the phalanges are occasionally seen (Hartman 1966; Simmons et al 1986). Supernumerary nipples and nipple or breast hypoplasia are also seen...nystagmus, uveitis, retinal pigment epithelial abnormalities, foveal hypoplasia , vitreous hemorrhage, and optic atrophy (Francois 1984; Lee et al...patients with incontinentia pigmenti include small vessel occlusions, hypoplasia of the corpus callosum, enlargement of the lateral ventricles, and

  6. 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...

  7. 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…

  8. Endocrine and Local Control of the Primate Corpus Luteum

    PubMed Central

    Stouffer, Richard L.; Bishop, Cecily V.; Bogan, Randy L.; Xu, Fuhua; Hennebold, Jon D.

    2014-01-01

    The primate corpus luteum is a transient endocrine gland that differentiates from the ovulatory follicle midway through the ovarian (menstrual) cycle. Its formation and limited lifespan is critical for fertility, as luteal-derived progesterone is the essential steroid hormone required for embryo implantation and maintenance of intra-uterine pregnancy until the placenta develops. It is well-established that LH and the LH-like hormone, CG, are the vital luteotropic hormones during the menstrual cycle and early pregnancy, respectively. Recent advances, particularly through genome analyses and cellular studies, increased our understanding of various local factors and cellular processes associated with the development, maintenance and repression of the corpus luteum. These include paracrine or autocrine factors associated with angiogenesis (e.g., VEGF), and that mediate LH/CG actions (e.g., progesterone), or counteract luteotropic effects (i.e., local luteolysis; e.g., PGF2α). However, areas of mystery and controversy remain, particularly regarding the signals and events that initiate luteal regression in the non-fecund cycle. Novel approaches capable of gene “knockdown” or amplification”, in vivo as well as in vitro, should identify novel or underappreciated gene products that are regulated by or modulate LH/CG actions to control the functional lifespan of the primate corpus luteum. Further advances in our understanding of luteal physiology will help to improve or control fertility for purposes ranging from preservation of endangered primate species to designing novel ovary-based contraceptives and treating ovarian disorders in women. R01 HD020869, R01 HD042000, U54 HD018185, U54 HD055744, P51 OD011092, T32 HD007133, Bayer Schering Pharma AG. PMID:24287034

  9. Chromosomal abnormalities and mental illness.

    PubMed

    MacIntyre, D J; Blackwood, D H R; Porteous, D J; Pickard, B S; Muir, W J

    2003-03-01

    Linkage studies of mental illness have provided suggestive evidence of susceptibility loci over many broad chromosomal regions. Pinpointing causative gene mutations by conventional linkage strategies alone is problematic. The breakpoints of chromosomal abnormalities occurring in patients with mental illness may be more direct pointers to the relevant gene locus. Publications that describe patients where chromosomal abnormalities co-exist with mental illness are reviewed along with supporting evidence that this may amount to an association. Chromosomal abnormalities are considered to be of possible significance if (a) the abnormality is rare and there are independent reports of its coexistence with psychiatric illness, or (b) there is colocalisation of the abnormality with a region of suggestive linkage findings, or (c) there is an apparent cosegregation of the abnormality with psychiatric illness within the individual's family. Breakpoints have been described within many of the loci suggested by linkage studies and these findings support the hypothesis that shared susceptibility factors for schizophrenia and bipolar disorder may exist. If these abnormalities directly disrupt coding regions, then combining molecular genetic breakpoint cloning with bioinformatic sequence analysis may be a method of rapidly identifying candidate genes. Full karyotyping of individuals with psychotic illness especially where this coexists with mild learning disability, dysmorphism or a strong family history of mental disorder is encouraged.

  10. 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.

  11. Haematological abnormalities in mitochondrial disorders

    PubMed Central

    Finsterer, Josef; Frank, Marlies

    2015-01-01

    INTRODUCTION This study aimed to assess the kind of haematological abnormalities that are present in patients with mitochondrial disorders (MIDs) and the frequency of their occurrence. METHODS The blood cell counts of a cohort of patients with syndromic and non-syndromic MIDs were retrospectively reviewed. MIDs were classified as ‘definite’, ‘probable’ or ‘possible’ according to clinical presentation, instrumental findings, immunohistological findings on muscle biopsy, biochemical abnormalities of the respiratory chain and/or the results of genetic studies. Patients who had medical conditions other than MID that account for the haematological abnormalities were excluded. RESULTS A total of 46 patients (‘definite’ = 5; ‘probable’ = 9; ‘possible’ = 32) had haematological abnormalities attributable to MIDs. The most frequent haematological abnormality in patients with MIDs was anaemia. 27 patients had anaemia as their sole haematological problem. Anaemia was associated with thrombopenia (n = 4), thrombocytosis (n = 2), leucopenia (n = 2), and eosinophilia (n = 1). Anaemia was hypochromic and normocytic in 27 patients, hypochromic and microcytic in six patients, hyperchromic and macrocytic in two patients, and normochromic and microcytic in one patient. Among the 46 patients with a mitochondrial haematological abnormality, 78.3% had anaemia, 13.0% had thrombopenia, 8.7% had leucopenia and 8.7% had eosinophilia, alone or in combination with other haematological abnormalities. CONCLUSION MID should be considered if a patient’s abnormal blood cell counts (particularly those associated with anaemia, thrombopenia, leucopenia or eosinophilia) cannot be explained by established causes. Abnormal blood cell counts may be the sole manifestation of MID or a collateral feature of a multisystem problem. PMID:26243978

  12. Congenital abnormalities and selective abortion.

    PubMed

    Seller, M J

    1976-09-01

    The technique of amniocentesis, by which an abnormal fetus can be detected in utero, has brought a technological advance in medical science but attendant medical and moral problems. Dr Seller describes those congenital disabilities which can be detected in the fetus before birth, for which the "remedy" is selective abortion. She then discusses the arguments for and against selective abortion, for the issue is not simple, even in the strictly genetic sense of attempting to ensure a population free of congenital abnormality.

  13. 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…

  14. 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…

  15. A Corpus-Based Approach to Online Materials Development for Writing Research Articles

    ERIC Educational Resources Information Center

    Chang, Ching-Fen; Kuo, Chih-Hua

    2011-01-01

    There has been increasing interest in the possible applications of corpora to both linguistic research and pedagogy. This study takes a corpus-based, genre-analytic approach to discipline-specific materials development. Combining corpus analysis with genre analysis makes it possible to develop teaching materials that are not only authentic but…

  16. TOEFL11: A Corpus of Non-Native English. Research Report. ETS RR-13-24

    ERIC Educational Resources Information Center

    Blanchard, Daniel; Tetreault, Joel; Higgins, Derrick; Cahill, Aoife; Chodorow, Martin

    2013-01-01

    This report presents work on the development of a new corpus of non-native English writing. It will be useful for the task of native language identification, as well as grammatical error detection and correction, and automatic essay scoring. In this report, the corpus is described in detail.

  17. 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 pattern of…

  18. The Pedagogical Mediation of a Developmental Learner Corpus for Classroom-Based Language Instruction

    ERIC Educational Resources Information Center

    Belz, Julie A.; Vyatkina, Nina

    2008-01-01

    Although corpora have been used in language teaching for some time, few empirical studies explore their impact on learning outcomes. We provide a microgenetic account of learners' responses to corpus-driven instructional units for German modal particles and pronominal "da"-compounds. The units are based on developmental corpus data produced by…

  19. Using Edit Distance to Analyse Errors in a Natural Language to Logic Translation Corpus

    ERIC Educational Resources Information Center

    Barker-Plummer, Dave; Dale, Robert; Cox, Richard; Romanczuk, Alex

    2012-01-01

    We have assembled a large corpus of student submissions to an automatic grading system, where the subject matter involves the translation of natural language sentences into propositional logic. Of the 2.3 million translation instances in the corpus, 286,000 (approximately 12%) are categorized as being in error. We want to understand the nature of…

  20. 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…