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Sample records for corpus callosum atrophy

  1. Corpus callosum atrophy in patients with mild Alzheimer's disease

    DEFF Research Database (Denmark)

    Frederiksen, Kristian Steen; Garde, Ellen; Skimminge, Arnold

    2011-01-01

    Several studies have found atrophy of the corpus callosum (CC) in patients with Alzheimer's disease (AD). However, it remains unclear whether callosal atrophy is already present in the early stages of AD, and to what extent it may be associated with other structural changes in the brain......, such as age-related white matter changes (ARWMC) and progression of the disease....

  2. Clinical significance of corpus callosum atrophy in a mixed elderly population

    DEFF Research Database (Denmark)

    Ryberg, C; Rostrup, E; Stegmann, M B;

    2007-01-01

    Corpus callosum (CC) is the main tract connecting the hemispheres, but the clinical significance of CC atrophy is poorly understood. The aim of this work was to investigate clinical and functional correlates of CC atrophy in subjects with age-related white matter changes (ARWMC). In 569 elderly......) score, history of depression, geriatric depression scale (GDS) score, subjective gait difficulty, history of falls, walking speed, and total score on the short physical performance battery (SPPB) were analyzed. Significant correlations between CC atrophy and MMSE, SPPB, and walking speed were identified...

  3. Atrophy of the corpus callosum correlates with white matter lesions in patients with cerebral ischaemia

    Energy Technology Data Exchange (ETDEWEB)

    Meguro, K.; Yamadori, A. [Section of Neuropsychology, Division of Disability Science, Tohoku University Graduate School of Medicine, 2-1, Seiryo-machi, Aoba-ku, 980-8575 Sendai (Japan); Constans, J.M.; Courtheoux, P.; Theron, J. [MR Unit, University of Caen School of Medicine, Caen (France); Viader, F. [Department of Neuroradiology, University of Caen School of Medicine, Caen (France)

    2000-06-01

    Many studies of white matter high signal (WMHS) on T2-weighted MRI have disclosed that it is related to cerebral ischaemia and to brain atrophy. Atrophy of the corpus callosum (CC) has also been studied in relation to ischaemia. Our objective was to test the hypothesis that CC atrophy could be due to ischaemia. We therefore assessed CC, WMHS and brain atrophy in patients with risk factors without strokes (the risk factor group) and in those with infarcts (the infarct group), to investigate the relationships between these factors. We studied 30 patients in the infarct group, 14 in the risk factor group, and 29 normal subjects. Using axial T1-weighted MRI, cortical atrophy and ventricular enlargement (brain atrophy) were visually rated. Using axial T2-weighted MRI, WMHS was assessed in three categories: periventricular symmetrical, periventricular asymmetrical and subcortical. Using the mid-sagittal T1-weighted image, the CC was measured in its anterior, posterior, midanterior and midposterior portions. In the normal group, no correlations were noted between parameters. In the infarct group, there were significant correlations between CC and brain atrophy, and between CC atrophy and WMHS. After removing the effects of age, gender and brain atrophy, significant correlations were noted between some CC measures and subcortical WMHS. In the risk factor group, there were significant correlations between CC and brain atrophy and between CC atrophy and WMHS. After allowance for age, gender and brain atrophy, significant correlations between some CC measures and periventricular WMHS remained. The hypothesis that CC atrophy could be due to cerebral ischaemia was supported by other analyses. Namely, for correlations between the extent of infarcts and partial CC atrophy in patients with anterior middle cerebral artery (MCA) and with posterior MCA infarcts, there were significant correlations between the extent of infarct and midanterior CC atrophy in the former, and posterior

  4. White matter changes contribute to corpus callosum atrophy in the elderly: The LADIS study

    DEFF Research Database (Denmark)

    Ryberg, C.; Rostrup, E.; Sjöstrand, Karl

    2008-01-01

    BACKGROUND AND PURPOSE: The corpus callosum (CC) is the most important structure involved in the transmission of interhemispheric information. The aim of this study was to investigate the potential correlation between regional age-related white matter changes (ARWMC) and atrophy of CC in elderly...... subjects.MATERIALS AND METHODS: In 578 subjects with ARWMC from the Leukoaraiosis And DISability (LADIS) study, the cross-sectional area of the CC was automatically segmented on the normalized midsagittal MR imaging section and subdivided into 5 regions The ARWMC volumes were measured quantitatively...

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

    DEFF Research Database (Denmark)

    Jokinen, Hanna; Ryberg, Charlotte; Kalska, Hely

    2007-01-01

    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...... 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...

  6. Corpus callosum atrophy is associated with mental slowing and executive deficits in subjects with age-related white matter hyperintensities. The LADIS study

    DEFF Research Database (Denmark)

    Jokinen, Hanne; Ryberg, Charlotte; Stegmann, Mikkel Bille

    2007-01-01

    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...... 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...

  7. Clinical significance of corpus callosum atrophy in a mixed elderly population.

    Science.gov (United States)

    Ryberg, C; Rostrup, E; Stegmann, M B; Barkhof, F; Scheltens, P; van Straaten, E C W; Fazekas, F; Schmidt, R; Ferro, J M; Baezner, H; Erkinjuntti, T; Jokinen, H; Wahlund, L-O; O'brien, J; Basile, A M; Pantoni, L; Inzitari, D; Waldemar, G

    2007-06-01

    Corpus callosum (CC) is the main tract connecting the hemispheres, but the clinical significance of CC atrophy is poorly understood. The aim of this work was to investigate clinical and functional correlates of CC atrophy in subjects with age-related white matter changes (ARWMC). In 569 elderly subjects with ARWMC from the Leukoaraiosis And DISability (LADIS) study, the CC was segmented on the normalised mid-sagittal magnetic resonance imaging (MRI) slice and subdivided into five regions. Correlations between the CC areas and subjective memory complaints, mini mental state examination (MMSE) score, history of depression, geriatric depression scale (GDS) score, subjective gait difficulty, history of falls, walking speed, and total score on the short physical performance battery (SPPB) were analyzed. Significant correlations between CC atrophy and MMSE, SPPB, and walking speed were identified, and the CC areas were smaller in subjects with subjective gait difficulty. The correlations remained significant after correction for ARWMC grade. In conclusion, CC atrophy was independently associated with impaired global cognitive and motor function in subjects with ARWMC.

  8. Quantitative analysis of structural variations in corpus callosum in adults with multiple system atrophy (MSA)

    Science.gov (United States)

    Bhattacharya, Debanjali; Sinha, Neelam; Saini, Jitender

    2017-03-01

    Multiple system atrophy (MSA) is a rare, non-curable, progressive neurodegenerative disorder that affects nervous system and movement, poses a considerable diagnostic challenge to medical researchers. Corpus callosum (CC) being the largest white matter structure in brain, enabling inter-hemispheric communication, quantification of callosal atrophy may provide vital information at the earliest possible stages. The main objective is to identify the differences in CC structure for this disease, based on quantitative analysis on the pattern of callosal atrophy. We report results of quantification of structural changes in regional anatomical thickness, area and length of CC between patient-groups with MSA with respect to healthy controls. The method utilizes isolating and parcellating the mid-sagittal CC into 100 segments along the length - measuring the width of each segment. It also measures areas within geometrically defined five callosal compartments of the well-known Witelson, and Hofer-Frahma schemes. For quantification, statistical tests are performed on these different callosal measurements. From the statistical analysis, it is concluded that compared to healthy controls, width is reduced drastically throughout CC for MSA group and as well as changes in area and length are also significant for MSA. The study is further extended to check if any significant difference in thickness is found between the two variations of MSA, Parkinsonian MSA and Cerebellar MSA group, using the same methodology. However area and length of this two sub-MSA group, no substantial difference is obtained. The study is performed on twenty subjects for each control and MSA group, who had T1-weighted MRI.

  9. Dysgenesis of the corpus callosum

    Energy Technology Data Exchange (ETDEWEB)

    Kendall, B.E.

    1983-08-01

    The embryology of the corpus callosum is briefly reviewed in relation to dysgenesis and associated malformations. The morphology, etiology, clinical and radiological features of such malformations are discussed and illustrated.

  10. Clinical significance of corpus callosum atrophy in a mixed elderly population

    DEFF Research Database (Denmark)

    Ryberg, C.; Rostrup, E.; Stegmann, Mikkel Bille

    2007-01-01

    , and the CC areas were smaller in subjects with subjective gait difficulty. The correlations remained significant after correction for ARWMC grade. In conclusion, CC atrophy was independently associated with impaired global cognitive and motor function in subjects with ARWMC. (c) 2006 Elsevier Inc. All rights...

  11. Hypnotizability and Corpus Callosum Morphology

    OpenAIRE

    Horton, James Edward

    1999-01-01

    Hypnotizability and Corpus Callosum Morphology By James E. Horton Committee Chair: Helen J. Crawford, Ph.D. Department of Psychology (Abstract) In general, highly hypnotizable individuals ("highs") have exhibited greater abilities to focus attention and inhibit pain than low hypnotizable individuals ("lows"). Furthermore, highs appear to have faster neural processing than lows. The present study investigated differences between lows and highs in morphological volume of s...

  12. Diffusion tensor analysis of corpus callosum in progressive supranuclear palsy

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    Ito, Shoichi; Makino, Takahiro; Shirai, Wakako; Hattori, Takamichi [Department of Neurology, Graduate School of Medicine, Chiba University (Japan)

    2008-11-15

    Progressive supranuclear palsy (PSP) is a neurodegenerative disease featuring parkinsonism, supranuclear ophthalmoplegia, dysphagia, and frontal lobe dysfunction. The corpus callosum which consists of many commissure fibers probably reflects cerebral cortical function. Several previous reports showed atrophy or diffusion abnormalities of anterior corpus callosum in PSP patients, but partitioning method used in these studies was based on data obtained in nonhuman primates. In this study, we performed a diffusion tensor analysis using a new partitioning method for the human corpus callosum. Seven consecutive patients with PSP were compared with 29 age-matched patients with Parkinson's Disease (PD) and 19 age-matched healthy control subjects. All subjects underwent diffusion tensor magnetic resonance imaging, and the corpus callosum was partitioned into five areas on the mid-sagittal plane according to a recently established topography of human corpus callosum (CC1-prefrontal area, CC2-premotor and supplementary motor area, CC3-motor area, CC4-sensory area, CC5-parietal, temporal, and occipital area). Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were measured in each area and differences between groups were analyzed. In the PSP group, FA values were significantly decreased in CC1 and CC2, and ADC values were significantly increased in CC1 and CC2. Receiver operating characteristic analysis showed excellent reliability of FA and ADC analyses of CC1 for differentiating PSP from PD. The anterior corpus callosum corresponding to the prefrontal, premotor, and supplementary motor cortices is affected in PSP patients. This analysis can be an additional test for further confirmation of the diagnosis of PSP.

  13. Corpus Callosum Area in Children and Adults with Autism

    Science.gov (United States)

    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…

  14. Magnetic resonance imaging study of corpus callosum ...

    African Journals Online (AJOL)

    2014-11-02

    Nov 2, 2014 ... gender and callosal measures in patient and control groups. In all groups of ..... our intelligence and problem-solving ability. The prefrontal cortex plays a role in the regulation of complex cognitive, emotional and .... in the corpus callosum in abuse-related posttraumatic stress disorder: A preliminary study. J.

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

    Science.gov (United States)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Andronikou, Savvas; Pillay, Tanyia; Gabuza, Lungile; Mahomed, Nasreen; Naidoo, Jaishree; Tebogo Hlabangana, Linda [University of the Witwatersrand, Radiology Department, Faculty of Health Sciences, Johannesburg (South Africa); Du Plessis, Vicci [University of KwaZulu-Natal, Radiology Department, Faculty of Health Sciences, Durban (South Africa); Prabhu, Sanjay P. [Harvard Medical School, Department of Radiology, Boston Children' s Hospital, Boston, MA (United States)

    2014-08-31

    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. (orig.)

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

    Science.gov (United States)

    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

  18. On Automating and Standardising Corpus Callosum Analysis in Brain MRI

    DEFF Research Database (Denmark)

    Stegmann, Mikkel Bille; Skoglund, Karl

    2005-01-01

    Corpus callosum analysis is influenced by many factors. The effort in controlling these has previously been incomplete and scattered. This paper sketches a complete pipeline for automated corpus callosum analysis from magnetic resonance images, with focus on measurement standardisation....... The presented pipeline deals with i) estimation of the mid-sagittal plane, ii) localisation and registration of the corpus callosum, iii) parameterisation and representation of its contour, and iv) means of standardising the traditional reference area measurements....

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

    OpenAIRE

    Paul, Lynn K.; 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 t...

  20. Delusional Disorder in a Patient with Corpus Callosum Agenesis

    OpenAIRE

    Bhatia, M. S.; 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, dis...

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

    Science.gov (United States)

    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.

  2. Morphometric changes of the corpus callosum in congenital blindness

    DEFF Research Database (Denmark)

    Tomaiuolo, Francesco; Campana, Serena; Collins, D Louis

    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...

  3. Cavernous Angioma of the Corpus Callosum Presenting with Acute Psychosis

    Directory of Open Access Journals (Sweden)

    Giacomo Pavesi

    2014-01-01

    Full Text Available 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.

  4. Delusional Disorder in a Patient with Corpus Callosum Agenesis

    Science.gov (United States)

    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

  5. Facial emotion recognition in agenesis of the corpus callosum

    OpenAIRE

    Bridgman, Matthew W.; Brown, Warren S.; Spezio, Michael L.; Leonard, Matthew K.; Adolphs, Ralph; Paul, Lynn K.

    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 ...

  6. Clinical significance of the corpus callosum in cerebral palsy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Ja; Kim, Ji Chang [The Catholic University of Korea, Seoul (Korea, Republic of); Kim, Jong Chul [School of Medicine, Chungnam National University, Taejon (Korea, Republic of); And Others

    2000-10-01

    To evaluate, using magnetic resonance (MR) imaging, the clinal significance of the corpus callosum by measuring the size of various portions of the corpus callosum in children with cerebral palsy, and in paired controls. Fifty-two children (30 boys and 22 girls aged between six and 96 (median, 19) months) in whom cerebral palsy was clinically diagnosed underwent MR imaging. There were 23 term patients and 29 preterm, and the control group was selected by age and sex matching. Clinal subtypes of cerebral palsy were classified as hemiplegia (n=14), spastic diplegia (n=22), or spastic quadriplegia (n=16), and according to the severity of motor palsy, the condition was also classified as mild (n=26), moderate (n=13), or severe (n=13). In addition to the length and height of the corpus callosum, the thickness of its genu, body, transitional zone and splenium, as seen on midsagittal T1-weighted MR images, were also measured. Differences in the measured values of the two groups were statistically analysed and differences in the size of the corpus callosum according to the clinical severity and subtypes of cerebral palsy, and gestational age, were also assessed. Except for height, the measured values of the corpus callosum in patients with cerebral palsy were significantly less than those of the control group (p less than 0.05). Its size decreased according to the severity of motor palsy. Compared with term patients, the corpus callosum in preterm patients was considerably smaller (p less than 0.05). There was statistically significant correlation between the severity of motor palsy and the size of the corpus callosum. Quantitative evaluation of the corpus callosum might be a good indicator of neurologic prognosis, and a sensitive marker for assessing the extent of brain injury.

  7. Hereditary spastic paraplegia with a thin corpus callosum

    Energy Technology Data Exchange (ETDEWEB)

    Somasundaram, Sivaraman; Kesavadas, Chandrasekharan [Sree Chitra Tirunal Institute for Medical Sciences and Technology, Department of Imaging Sciences and Interventional Radiology, Trivandrum (India); Raghavendra, Seetharam; Singh, Atampreet; Nair, Muraleedharan [Sree Chitra Tirunal Institute for Medical Sciences and Technology, Department of Neurology, Trivandrum (India)

    2007-05-15

    We report a 15-year-old boy with autosomal recessive complicated hereditary spastic paraplegia with a thin corpus callosum (HSP-TCC). The involvement of the corpus callosum was characteristic with the genu and body predominantly affected with relative sparing of the splenium. HSP-TCC is being increasingly recognized over a wider geographical area than earlier believed. We now report a case of HSP-TCC from the Indian subcontinent. (orig.)

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

    Science.gov (United States)

    Keogh, Mandy J; Ridgway, Sam H

    2008-07-01

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

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

    Directory of Open Access Journals (Sweden)

    Brianne M Bettcher

    Full Text Available 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.

  10. Polyethylene glycol restores axonal conduction after corpus callosum transection.

    Science.gov (United States)

    Bamba, Ravinder; Riley, D Colton; Boyer, Richard B; Pollins, Alonda C; Shack, R Bruce; Thayer, Wesley P

    2017-05-01

    Polyethylene glycol (PEG) has been shown to restore axonal continuity after peripheral nerve transection in animal models. We hypothesized that PEG can also restore axonal continuity in the central nervous system. In this current experiment, coronal sectioning of the brains of Sprague-Dawley rats was performed after animal sacrifice. 3Brain high-resolution microelectrode arrays (MEA) were used to measure mean firing rate (MFR) and peak amplitude across the corpus callosum of the ex-vivo brain slices. The corpus callosum was subsequently transected and repeated measurements were performed. The cut ends of the corpus callosum were still apposite at this time. A PEG solution was applied to the injury site and repeated measurements were performed. MEA measurements showed that PEG was capable of restoring electrophysiology signaling after transection of central nerves. Before injury, the average MFRs at the ipsilateral, midline, and contralateral corpus callosum were 0.76, 0.66, and 0.65 spikes/second, respectively, and the average peak amplitudes were 69.79, 58.68, and 49.60 μV, respectively. After injury, the average MFRs were 0.71, 0.14, and 0.25 spikes/second, respectively and peak amplitudes were 52.11, 8.98, and 16.09 μV, respectively. After application of PEG, there were spikes in MFR and peak amplitude at the injury site and contralaterally. The average MFRs were 0.75, 0.55, and 0.47 spikes/second at the ipsilateral, midline, and contralateral corpus callosum, respectively and peak amplitudes were 59.44, 45.33, 40.02 μV, respectively. There were statistically differences in the average MFRs and peak amplitudes between the midline and non-midline corpus callosum groups (P < 0.01, P < 0.05). These findings suggest that PEG restores axonal conduction between severed central nerves, potentially representing axonal fusion.

  11. Polyethylene glycol restores axonal conduction after corpus callosum transection

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    Ravinder Bamba

    2017-01-01

    Full Text Available Polyethylene glycol (PEG has been shown to restore axonal continuity after peripheral nerve transection in animal models. We hypothesized that PEG can also restore axonal continuity in the central nervous system. In this current experiment, coronal sectioning of the brains of Sprague-Dawley rats was performed after animal sacrifice. 3Brain high-resolution microelectrode arrays (MEA were used to measure mean firing rate (MFR and peak amplitude across the corpus callosum of the ex-vivo brain slices. The corpus callosum was subsequently transected and repeated measurements were performed. The cut ends of the corpus callosum were still apposite at this time. A PEG solution was applied to the injury site and repeated measurements were performed. MEA measurements showed that PEG was capable of restoring electrophysiology signaling after transection of central nerves. Before injury, the average MFRs at the ipsilateral, midline, and contralateral corpus callosum were 0.76, 0.66, and 0.65 spikes/second, respectively, and the average peak amplitudes were 69.79, 58.68, and 49.60 μV, respectively. After injury, the average MFRs were 0.71, 0.14, and 0.25 spikes/second, respectively and peak amplitudes were 52.11, 8.98, and 16.09 μV, respectively. After application of PEG, there were spikes in MFR and peak amplitude at the injury site and contralaterally. The average MFRs were 0.75, 0.55, and 0.47 spikes/second at the ipsilateral, midline, and contralateral corpus callosum, respectively and peak amplitudes were 59.44, 45.33, 40.02 μV, respectively. There were statistically differences in the average MFRs and peak amplitudes between the midline and non-midline corpus callosum groups (P < 0.01, P < 0.05. These findings suggest that PEG restores axonal conduction between severed central nerves, potentially representing axonal fusion.

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

    Science.gov (United States)

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

    Science.gov (United States)

    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.

  14. Study of corpus callosum in experimental hydrocephalic wistar rats

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    Lopes Luiza da Silva

    2003-01-01

    Full Text Available PURPOSE: Hydrocephalus causes countless cerebral damages, especially on the structures around the ventricles. Hydrocephalic children present deficiencies in the nonverbal skills more than in the verbal skills, and not always revertible with an early treatment. As the corpus callosum has an important role in the nonverbal acquisition it is possible that the injuries in this structure are responsible for the cognitive dysfunctions of these children. This present study tries to establish the alterations caused by hydrocephalus on the corpus callosum of developing Wistar rats, induced by intracisternal injection of kaolin. METHODS : Seven, fourteen and twenty one days after the injection, the animals were killed, and the corpus callosum was dissected and prepared for the study of the axonal fibers. RESULTS AND CONCLUSION: The seven-day old rats in hydrocephalus development presented a delay in myelination in relation to the control rats. With the fourteen-day old rats in hydrocephalus development the corpus callosum showed a recovery of myelin, but with the twenty one-day old rats in hydrocephalus development the axonal fibers were damaged and reduced in number.

  15. Corpus callosum size correlates with asymmetric performance on a dichotic listening task in healthy aging but not in Alzheimer's disease

    NARCIS (Netherlands)

    L. Gootjes (Liselotte); A. Bouma (Anke); J.W. van Strien (Jan); R. van Schijndel; F. Barkhof (Frederik); P. Scheltens (Philip)

    2008-01-01

    textabstractAlzheimer's disease (AD) involves not only gray matter but also white matter pathology, as reflected by atrophy of the corpus callosum (CC). Since decreased CC size may indicate reduced functional interhemispheric connectivity, differences in callosal size may have cognitive consequences

  16. Corpus callosum size correlates with asymmetric performance on a dichotic listening task in healthy aging but not in Alzheimer's disease

    NARCIS (Netherlands)

    Gootjes, L; Bouma, A; Van Strien, JW; Van Schijndel, R; Barkhof, F; Scheltens, P

    2006-01-01

    Alzheimer's disease (AD) involves not only gray matter but also white matter pathology, as reflected by atrophy of the corpus callosum (CC). Since decreased CC size may indicate reduced functional interhemispheric connectivity, differences in callosal size may have cognitive consequences that may be

  17. Sexual dimorphism of the human corpus callosum: Digital morphometric study

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    Spasojević Goran

    2006-01-01

    Full Text Available Background/Aim. Changes in the morphology and the size of the corpus callosum, are related to various pathological conditions. An analysis of these changes requires data about sexual dimorphism of the corpus callosum, which we tried to obtain in our study. We also investigated the method of digital morphometry and compared the obtained results with the results of other authors obtained by magnetic resonance imaging or by planimetry. Methods. A morphological research included 34 human brains (cadavers of both sexes − 19 female and 15 male aged 26−72 years. By digital morphometry using an AutoCAD software we performed measurements in the corpus callosum: the length (L, width in the half of its length (WW’, length of its cortical margin (LCM, area and perimeter of the anterior and posterior callosal segments, as well as the area and perimeter of the corpus callosum section area. The investigated parameters were analyzed and compared between the females and males. Results. There was not a statistically significant difference between the males and females in the investigated parameters of the corpus callosum (t test; p > 0.05, including the mean values of the two most important parameters, the surface of its midsagittal section area (males 654.11 mm2; females 677.40 mm2 and of its perimeter (males 19.61 cm; females 19.72 cm. The results obtained by digital morphometry were in the range of the results of other authors obtained by magnetic resonance and by planimetry. However, the value of Pearson coefficient of linear correlation between the section surface area and perimeter of the corpus callosum in the males was highly significant (rxy = 0.6943, p < 0.01, while in the females this value was statistically insignificant. Conclusion. Digital morphometry is accurate method in encephalometric investigations. Our results suggest that the problem of sexual dimorphism of the corpus callosum is very complex, because the identical variables (section

  18. A MRI quantitative study of corpus callosum in normal adults

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Objective: To investigate the possible age- and sex-related differences in the various dimensions of corpus callosum among Chinese normal adults. Methods: Magnetic resonance images of 286 healthy adults, including 127 males and 159 females, and ranging in age from 20 to 81 years, were investigated. They were classified into 5 age groups (20-29, 30-9, 40-49, 50-59, and 60-81 years old). Corresponding to the age group sequence above, the male/female ratio of each group respectively was: 25/26, 26/33, 33/50, 32/36, and 11/14. The following dimensions of corpus callosum were systematically measured on the midsagittal T1-weighted images: frontal to occipital pole (represented as line segment AB), total longitudinal dimension of the corpus callosum (CD), the maximum height (EF), the widths of the genu (CX), anterior one third (GH), central region (EZ), posterior one third (MN) and splenium (YD). After that, the obtained data was analyzed statistically. Results: (1) The total longitudinal dimension, maximum height, widths of the genu, central region and splenium were proved to be larger in females. But the widths of the anterior one third and posterior one third were similar in-between. In spite of that, a conspicuous sex-related difference was not found. (2) The total longitudinal dimension and the maximum height of the corpus callosum remained stable in all age subgroups. Yet the widths of the genu, anterior one third, central region, posterior one third and splenium had a tendency of decreasing gradually with aging. Statistical difference was seen in the anterior one third, central region, posterior one third (P<0.05). Conclusion: There is no sex-related difference in all dimensions of corpus callosum. But, with aging, a significant difference is found in the widths of the anterior one third, central region and posterior one third.

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

    Science.gov (United States)

    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

  20. Corpus callosum agenesis: Role of fetal magnetic resonance imaging

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    Achour Radhouane

    2016-05-01

    Full Text Available Corpus callosum agenesis (CCA was evaluated by ultrasound examination and magnetic resonance imaging (MRI with many studies. Ultrasonography was able to suspect CCA by indirect signs but a definitive diagnosis of CCA was achieved in rare cases. MRI was able to diagnose complete CCA in majority of cases. Additional neurological abnormalities including heterotopia, gyration anomaly, asymmetry of the cerebral hemispheres, and Dandy-Walker variant were documented, as well as an ocular anomaly which was described, by MRI examination. Prenatal counseling for fetal agenesis of the corpus callosum is difficult as the prognosis is uncertain. The association with other cerebral abnormalities increases the likelihood of a poor outcome and ultrasonographic assessment of the fetal brain is limited. We found MRI to be a safe and useful additional procedure to complement ultrasonographic diagnosis or suspicion of CCA.

  1. Emotional Intelligence in Agenesis of the Corpus Callosum.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  3. Clinical features of hereditary spastic paraplegia with thin corpus callosum:report of 5 Chinese cases

    Institute of Scientific and Technical Information of China (English)

    唐北沙; 陈昕; 赵国华; 沈璐; 严新翔; 江泓; 罗巍

    2004-01-01

    Background Hereditary spastic paraplegia is a clinically and genetically heterogeneous group of neurodegenerative disorders of the motor system, characterized by slowly progressive spasticity and weakness of the lower extremities. This study was conducted to investigate the clinical features of hereditary spastic paraplegia with thin corpus callosum (HSP-TCC). Methods Clinical data from five patients and thirty-five previously published case reports of HSP-TCC were analyzed retrospectively. Results Most patients were adolescents at the onset of the disease, presenting with spastic paraparesis of the lower limbs and mental impairment. Some patients also had other clinical features, including spasticity of the upper limbs, cerebellar ataxia, and sensory disturbances. Cranial MRIs of the five patients revealed an extremely thin corpus callosum, sometimes with widened cerebral sulci and ventricles, as well as with cerebellar and cerebral atrophy. Conclusion The main clinical features of HSP-TCC include slowly progressive spastic paraplegia, mental impairment during the second decade of life, and an extremely thin corpus callosum as shown on cranial MRIs.

  4. Automated measurement of the human corpus callosum using MRI

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    Timothy J Herron

    2012-09-01

    Full Text Available The corpus callosum includes the majority of fibers that connect the two cortical hemispheres. Studies of cross-sectional callosal morphometry and area have revealed developmental, gender, and hemispheric differences in healthy populations and callosal deficits associated with neurodegenerative disease and brain injury. However, accurate quantification of the callosum using magnetic resonance imaging is complicated by intersubject variability in callosal size, shape, and location and often requires manual outlining of the callosum in order to achieve adequate performance. Here we describe an objective, fully automated protocol that utilizes voxel-based image to quantify the area and thickness both of the entire callosum and of different callosal compartments. We verify the method’s accuracy, reliability, robustness and multisite consistency and make comparisons with manual measurements using public brain-image databases. An analysis of age-related changes in the callosum showed increases in length and reductions in thickness and area with age. A comparison of older subjects with and without mild dementia revealed that reductions in anterior callosal area independently predicted poorer cognitive performance after factoring out Mini-Mental Status Examination scores and normalized whole brain volume. Open-source software implementing the algorithm is available at www.nitrc.org/projects/c8c8.

  5. Electroconvulsive Therapy and Corpus Callosum Aplasia: A 3-Year Followup

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    Ulrich Palm

    2011-01-01

    Full Text Available Electroconvulsive Therapy (ECT is a powerful treatment option in severe or chronic catatonic states and has been reported to be useful in oligophrenic patients. We report the followup medical history of a patient with corpus callosum aplasia (or agenesis who was continuously treated with ECT over three years. First, he improved considerably after a series of ECT, but relapses of catatonia made a continuous, weekly ECT necessary. Due to the severity of the brain malformation, an add-on medication with benzodiazepines and second generation antipsychotics was necessary to treat catatonic symptoms. This case emphasises the benefits of long-term ECT in oligophrenic patients.

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

    Science.gov (United States)

    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.

  7. Corpus callosum tissue loss and development of motor and global cognitive impairment

    DEFF Research Database (Denmark)

    Frederiksen, Kristian S; Garde, Ellen; Skimminge, Arnold

    2011-01-01

    To examine the impact of corpus callosum (CC) tissue loss on the development of global cognitive and motor impairment in the elderly.......To examine the impact of corpus callosum (CC) tissue loss on the development of global cognitive and motor impairment in the elderly....

  8. Microstructural changes in thickened corpus callosum in children: contribution of magnetic resonance diffusion tensor imaging

    Energy Technology Data Exchange (ETDEWEB)

    Merlini, Laura; Anooshiravani, Mehrak; Kanavaki, Aikaterini; Hanquinet, Sylviane [University of Geneva Children' s Hospital, Pediatric Radiology Unit, Geneva (Switzerland)

    2015-06-15

    Thickened corpus callosum is a rare finding and its pathophysiology is not well known. An anomalous supracallosal bundle has been depicted by fiber tracking in some cases but no diffusion tensor imaging metrics of thickened corpus callosum have been reported. To use diffusion tensor imaging (DTI) in cases of thickened corpus callosum to help in understanding its clinical significance. During a 7-year period five children (ages 6 months to 15 years) with thickened corpus callosum were studied. We determined DTI metrics of fractional anisotropy (FA), mean diffusivity, and axial (λ1) and radial (λ2, λ3) diffusivity and performed 3-D fiber tracking reconstruction of the thickened corpus callosum. We compared our results with data from the literature and 24 age-matched controls. Brain abnormalities were seen in all cases. All children had at least three measurements of corpus callosum thickness above the 97th percentile according to age. In all children 3-D fiber tracking showed an anomalous supracallosal bundle and statistically significant decrease in FA (P = 0.003) and λ1 (P = 0.001) of the corpus callosum compared with controls, but no significant difference in mean diffusivity and radial diffusivity. Thickened corpus callosum was associated with abnormal bundles, suggesting underlying axonal guidance abnormality. DTI metrics suggested abnormal fiber compactness and density, which may be associated with alterations in cognition. (orig.)

  9. Corpus callosum tissue loss and development of motor and global cognitive impairment

    DEFF Research Database (Denmark)

    Frederiksen, Kristian Steen; Garde, Ellen; Skimminge, Arnold;

    2011-01-01

    To examine the impact of corpus callosum (CC) tissue loss on the development of global cognitive and motor impairment in the elderly.......To examine the impact of corpus callosum (CC) tissue loss on the development of global cognitive and motor impairment in the elderly....

  10. [Assessment of length and area of corpus callosum by three-dimensional ultrasonography].

    Science.gov (United States)

    Visentainer, Milena; Araujo Júnior, Edward; Rolo, Liliam Cristine; Nardozza, Luciano Marcondes Machado; Moron, Antonio Fernandes

    2010-12-01

    to establish reference values for the length and area of the fetal corpus callosum between the 20th and 33rd weeks of gestation using three-dimensional ultrasound (3DUS). this cross-sectional study involved 70 normal pregnancies with gestational age between 20 and 33 weeks. An Accuvix XQ instrument with a convex volumetric transducer (3 to 5 MHz) was used. To assess the corpus callosum, a transfrontal plane was obtained using the metopic suture as an acoustic window. Length was obtained by measuring the distance between the proximal and distal extremities of the corpus callosum. Area was obtained by manual tracing of the external corpus callosum surface. The means, medians, standard deviations, and maximum and minimum values were calculated for the corpus callosum length and area. Scatter graphs were created to analyze the correlation between corpus callosum length and area and gestational age and biparietal diameter, the quality adjustments was verified according to the determination coefficient (R²). The intraclass correlation coefficient (ICC) was used to assess the intraobserver variability. mean corpus callosum length increased from 21.7 (18.6 - 25.2 mm) to 38.7 mm (32.6 - 43.3 mm) between 20 and 33 weeks of pregnancy, respectively. Mean corpus callosum area increased from 55.2 (41.0 - 80.0 mm²) to 142.2 mm² (114.0 - 160.0 mm²), between 20 to 33 weeks of pregnancy, respectively. There was a strong correlation between corpus callosum length and area and gestational age (R² = 0.7 and 0.7, respectively) and biparietal diameter (R² = 0.7 and 0.6, respectively). Intraobserver variability was appropriate, with an ICC of 0.9 and 0.9 for length and area, respectively. reference values for corpus callosum length and area were established for fetuses between 20 and 33 weeks gestation. Intraobserver variability was appropriate.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  13. Agenesis of corpus callosum and emotional information processing in schizophrenia

    Directory of Open Access Journals (Sweden)

    Emmanuel eStip

    2012-02-01

    Full Text Available Corpus callosum (CC is essential in providing the integration of information related to perception and action within a subcortico-cortical network, thus supporting the generation of a unified experience about and reaction to changes in the environment. Its role in schizophrenia is yet to be fully elucidated, but there is accumulating evidence that there could be differences between patients and healthy controls regarding the morphology and function of CC, especially when individuals face emotionally laden information. Here, we report a case study of a patient with partial agenesis of corpus callosum (agCC patient with agenesis of the anterior aspect, above the genu and we provide a direct comparison with a group of patients with no apparent callosal damage (CC group regarding the brain activity during the processing of emotionally-laden information. We found that although the visual cortex activation in response to visual stimuli regardless of their emotional content was comparable in agCC patient and CC group both in terms of localization and intensity of activation, we observed a very large, non-specific and non-lateralized cerebral activation in the agCC patient, in contrast with the CC group, which showed a more lateralized and spatially localized activation, when the emotional content of the stimuli was considered. Further analysis of brain activity in the regions obtained in the CC group revealed that the agCC patient actually had an opposite activation pattern relative to most participants with no CC agenesis, indicating a dysfunctional response to these kind of stimuli, consistent with the clinical presentation of this particular patient. Our results seem to give support to the disconnection hypothesis which posits that the core symptoms of schizophrenia are related to aberrant connectivity between distinct brain areas, especially when faced with emotional stimuli, a fact consistent with the clinical tableau of this particular patient.

  14. Incidentally discovered colpocephaly and corpus callosum agenesis in asymptomatic adult patient

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    Huseyin Buyukgol

    2016-09-01

    Full Text Available The corpus callosum is the biggest commissural structure located in two brain hemispheres and it ensures the connection between cortical and subcortical neurons. The agenesis of the corpus callosum is generally diagnosed in the prenatal period or childhood. It is observed along with congenital abnormalities such as mental and motor retardation, seizures, myelomeningocele. In this article, we reported a case of colpocephaly and corpus callosum agenesis with no symptoms that diagnosed incidentally. [Cukurova Med J 2016; 41(3.000: 564-566

  15. Agenesis of the corpus callosum in a newborn with Turner mosaicism

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    Ester Pereira

    2014-05-01

    Full Text Available The agenesis of the corpus callosum results from a failure in the development of the largest fiber bundle that connects cerebral hemispheres. Patient’s outcome is influenced by etiology and associated central nervous system malformations. We describe a child with Turner syndrome (TS mosaicism, with particular phenotype features and a complete agenesis of the corpus callosum. To our knowledge, this is the second case report of TS mosaicism associated with complete agenesis of the corpus callosum. Anatomical brain magnetic resonance imaging and diffusion tensor imaging were useful to confirm the complete absence of the corpus callosum, evaluate associated central nervous system malformations, visualize abnormal white matter tracts (Probst bundles and assess the remaining commissures.

  16. Form of the male and female corpus callosum internal organization at the mature age

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    Юрий Петрович Костиленко

    2016-04-01

    Full Text Available Aim: to study the special features of the male and female corpus callosum internal organization at the mature age.Materials and methods: the total preparations of the male and female corpus callosum (10 preparation of each sex at 45–60 years old were used as the material. The given preparations were used to get from it the plate cuts in the two mutually perpendicular planes with 2 mm. thick. Then the received tissue plates of the corpus callosum underwent plastination in the epoxy. Then the preparations were extracted from the non-polymerized epoxy and placed on the polyethylene film that was covered with the other film of the same size. Further this stratified block was placed amid the two glasses of the equal size that shrunk together by placing the small load on it. After the complete polymerization the received epoxy plates with the corpus callosum tissue contained in it underwent the gentle grinding and the accurate polish and as the result was obtained the surface denudation of its tissue structures that were colored with the 1 % solution of blue methylene for 1% borax solution.Results of research: at the study of the corpus callosum plastinated cuts in saggital plane was revealed that the transverse platen-form elevations of its higher surface are the cord-form tenias standing out from within and going through the corpus callosum. At its studying in the transverse cut was established that in adults can be separated two types of corpus callosum by its density: the dense one and disperse one.At the large increases of the binocular loupe (microscope MBS-9 can be seen the gaps between the adjacent commissural cords. Within it can be detected the blood vessels. On the transverse cut of commissural cords in its depth are revealed the thinnest streaks which totality consists of the two alternate dark and light lines that form the layered striation. Among the series of the light lines are visible the interlayer that separate the whole depth of

  17. Greig cephalopolysyndactyly syndrome with dysgenesis of the corpus callosum in a Bedouin family.

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    Marafie, M J; Temtamy, S A; Rajaram, U; al-Awadi, S A; el-Badramany, M H; Farag, T I

    1996-12-18

    We report on the first known Bedouin family with Greig cephalopolysyndactyly syndrome (MIM 175700). The index patient and his father shared pre- and postaxial polysyndactyly, mild mental retardation, and corpus callosum dysgenesis. Their phenotypic findings were compared with reported cases of both Greig cephalopolysyndactyly (GCPS) and acrocallosal syndromes. This family represents the second report of the rare occurrence of dysgenesis of the corpus callosum in GCPS.

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

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    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 citicoline group were significantly lower than in control group (P 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.

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

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    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.

  20. Axonal pathfinding mechanisms at the cortical midline and in the development of the corpus callosum

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    Richards L.J.

    2002-01-01

    Full Text Available The corpus callosum is a large fiber tract that connects neurons in the right and left cerebral hemispheres. Agenesis of the corpus callosum (ACC is associated with a large number of human syndromes but little is known about why ACC occurs. In most cases of ACC, callosal axons are able to grow toward the midline but are unable to cross it, continuing to grow into large swirls of axons known as Probst bundles. This phenotype suggests that in some cases ACC may be due to defects in axonal guidance at the midline. General guidance mechanisms that influence the development of axons include chemoattraction and chemorepulsion, presented by either membrane-bound or diffusible molecules. These molecules are not only expressed by the final target but by intermediate targets along the pathway, and by pioneering axons that act as guides for later arriving axons. Midline glial populations are important intermediate targets for commissural axons in the spinal cord and brain, including the corpus callosum. The role of midline glial populations and pioneering axons in the formation of the corpus callosum are discussed. Finally the differential guidance of the ipsilaterally projecting perforating pathway and the contralaterally projecting corpus callosum is addressed. Development of the corpus callosum involves the coordination of a number of different guidance mechanisms and the probable involvement of a large number of molecules.

  1. Viscoelasticity of brain corpus callosum in biaxial tension

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    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.

  2. Effect of high-potency cannabis on corpus callosum microstructure.

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    Rigucci, S; Marques, T R; Di Forti, M; Taylor, H; Dell'Acqua, F; Mondelli, V; Bonaccorso, S; Simmons, A; David, A S; Girardi, P; Pariante, C M; Murray, R M; Dazzan, P

    2016-03-01

    The use of cannabis with higher Δ9-tetrahydrocannabinol content has been associated with greater risk, and earlier onset, of psychosis. However, the effect of cannabis potency on brain morphology has never been explored. Here, we investigated whether cannabis potency and pattern of use are associated with changes in corpus callosum (CC) microstructural organization, in patients with first-episode psychosis (FEP) and individuals without psychosis, cannabis users and non-users. The CC of 56 FEP (37 cannabis users) and 43 individuals without psychosis (22 cannabis users) was virtually dissected and segmented using diffusion tensor imaging tractography. The diffusion index of fractional anisotropy, mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity was calculated for each segment. Across the whole sample, users of high-potency cannabis had higher total CC MD and higher total CC AD than both low-potency users and those who never used (p = 0.005 and p = 0.004, respectively). Daily users also had higher total CC MD and higher total CC AD than both occasional users and those who never used (p = 0.001 and p cannabis is associated with disturbed callosal microstructural organization in individuals with and without psychosis. Since high-potency preparations are now replacing traditional herbal drugs in many European countries, raising awareness about the risks of high-potency cannabis is crucial.

  3. Tractography of the corpus callosum in Huntington's disease.

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    Owen Phillips

    Full Text Available 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.

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

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    Farshid eSepehrband

    2016-05-01

    Full Text Available 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.

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

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

    1995-08-01

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

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

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    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.

  7. Corpus callosal atrophy and associations with cognitive impairment in Parkinson disease.

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    Goldman, Jennifer G; Bledsoe, Ian O; Merkitch, Doug; Dinh, Vy; Bernard, Bryan; Stebbins, Glenn T

    2017-03-28

    To investigate atrophy of the corpus callosum on MRI in Parkinson disease (PD) and its relationship to cognitive impairment. One hundred patients with PD and 24 healthy control participants underwent clinical and neuropsychological evaluations and structural MRI brain scans. Participants with PD were classified as cognitively normal (PD-NC; n = 28), having mild cognitive impairment (PD-MCI; n = 47), or having dementia (PDD; n = 25) by Movement Disorder Society criteria. Cognitive domain (attention/working memory, executive function, memory, language, visuospatial function) z scores were calculated. With the use of FreeSurfer image processing, volumes for total corpus callosum and its subsections (anterior, midanterior, central, midposterior, posterior) were computed and normalized by total intracranial volume. Callosal volumes were compared between participants with PD and controls and among PD cognitive groups, covarying for age, sex, and PD duration and with multiple comparison corrections. Regression analyses were performed to evaluate relationships between callosal volumes and performance in cognitive domains. Participants with PD had reduced corpus callosum volumes in midanterior and central regions compared to healthy controls. Participants with PDD demonstrated decreased callosal volumes involving multiple subsections spanning anterior to posterior compared to participants with PD-MCI and PD-NC. Regional callosal atrophy predicted cognitive domain performance such that central volumes were associated with the attention/working memory domain; midposterior volumes with executive function, language, and memory domains; and posterior volumes with memory and visuospatial domains. Notable volume loss occurs in the corpus callosum in PD, with specific neuroanatomic distributions in PDD and relationships of regional atrophy to different cognitive domains. Callosal volume loss may contribute to clinical manifestations of PD cognitive impairment. © 2017 American

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

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    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.

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

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    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.

  10. Morphometry of the corpus callosum in Chinese children: relationship with gender and academic performance

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    Ng, Wing Hung Alex; Chan, Yu.Lung [Prince of Wales Hospital, Department of Diagnostic Radiology and Organ Imaging, Shatin, Hong Kong (Hong Kong); Au, Kit Sum Agnes [James Cook University, Department of Psychology, Townsville, Queensland (Australia); Yeung, Ka Wai David; Kwan, Ting Fai; To, Cho Yee

    2005-06-01

    The corpus callosum has been widely studied, but no study has demonstrated whether its size and shape have any relationship with language and calculation performance. To examine the morphometry of the corpus callosum of normal Chinese children and its relationship with gender and academic performance. One hundred primary school children (63 boys, 37 girls; age 6.5-10 years) were randomly selected and the standardized academic performance for each was ascertained. On the mid-sagittal section of a brain MRI, the length, height and total area of the corpus callosum and its thickness at different sites were measured. These were correlated with sex and academic performance. Apart from the normal average dimension of the different parts of the corpus callosum, thickness at the body-splenium junction in the average-to-good performance group was significantly greater than the below-average performance group in Chinese language (P=0.005), English language (P=0.02) and mathematics (P=0.01). The remainder of the callosal thickness showed no significant relationship with academic performance. There was no significant sex difference in the thickness of any part of the corpus callosum. These findings raise the suggestion that language and mathematics proficiency may be related to the morphometry of the fibre connections in the posterior parietal lobes. (orig.)

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

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    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

  12. Angular analysis of corpus callosum in 18 patients with frontonasal dysplasia

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    Giffoni Silvyo David Araújo

    2004-01-01

    Full Text Available Considering the rarity of the frontonasal dysplasia (FD and the few reports about it in a large casuistry using magnetic resonance image (MRI, we describe the results of the angular analysis of the corpus callosum of 18 individuals with FD (7 male, 11 female, using an easily-reproductive method. Group I had 12 individuals with isolated form and Group II had 6 individuals with FD syndromic with unknown etiology. The results are presented in set. Comparing with the control group, patients with FD presented alpha angle increase and beta and gamma angles reduction (p<0.05. Alpha and gamma angles express the relationship between the anterior portion of corpus callosum and the floor of 4th ventricle. Considering the embryonary development, these findings would occur secondarily to failure during the development of nasal capsula. Thus, angular anomaly in corpus callosum would be a usual finding, and not fortuitous in patients with FD.

  13. Meier-Gorlin syndrome with ventriculomegaly and hypoplastic corpus callosum: a rarely reported congenital malformation

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    Nabanita Kora

    2016-02-01

    Full Text Available Meier-Gorlin syndrome (MGS or ear-patella-short stature syndrome (MIM 224690 is a rarely reported autosomal recessive disorder having characteristic triad of microtia, short stature and aplastic or hypoplastic patella. Only 67 cases are reported. We are reporting a newborn female baby with typical features of MGS along with some other features never described before, ventriculomegaly and hypoplastic corpus callosum. We did x-rays of whole body (infantogram and MRI of brain for microcephaly. Ultrasonography of both knees showed absence of patellae and brain MRI showed ventriculomegaly and hypoplastic corpus callosum. To our best knowledge this is the second case report of MGS in India; the first reported a MGS associated with papilledema. In previously reported cases, there was no statement regarding agenesis of corpus callosum.

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

    Science.gov (United States)

    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.

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

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

    2012-02-23

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

  16. Infarction of the entire corpus callosum as a complication in subarachnoid hemorrhage: A case report

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    Satoru Takahashi, M.D.

    2017-03-01

    Full Text Available The corpus callosum is the major commissural pathway connecting the cerebral hemispheres. This pathway receives its blood supply from anterior communicating artery, pericallosal artery, and posterior pericallosal artery. However, in some cases, the entire corpus callosum is supplied by median callosal artery; thus, occlusion of this artery can lead to infarction of the entire corpus callosum. Few reports have described this type of infarction, and no reports after subarachnoid hemorrhage (SAH exist. Here, we report on a 42-year-old female who was diagnosed with SAH after two aneurysms were discovered in bifurcation of left anterior cerebral artery (A1-A2. After successful clipping was performed, the patient was alert and had no neurological deficits; moreover, the computed tomography images that were acquired after the operation showed no evidence of infarction. Nine days after admittance to the hospital, drowsiness and weakness of the left limbs with brain swelling appeared and decompressive hemi-craniectomy was performed. Diagnostic cerebral angiography revealed vasospasms in both anterior and middle cerebral arteries, thus fasudil hydrochloride was administered intra-arterially. While blood flow in all arteries improved, diffusion-weighted magnetic resonance imaging detected infarction along the entire length of the corpus callosum and in the medial region of the right frontal lobe. We believe this infarction was due to secondary ischemia of median callosal artery. This case reminded us of the anatomical variation wherein median callosal artery is the sole blood supply line for the corpus callosum and demonstrated that infarction of the entire corpus callosum is possible.

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

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    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.

  18. Marchiafava-Bignami disease: magnetic resonance imaging findings in corpus callosum and subcortical white matter

    Energy Technology Data Exchange (ETDEWEB)

    Kawarabuki, Kentaro E-mail: bukky@h2.dion.ne.jp; Sakakibara, Takehiko; Hirai, Makoto; Yoshioka, Yuji; Yamamoto, Yasumasa; Yamaki, Tarumi

    2003-11-01

    A case of Marchiafava-Bignami disease (MBD) is presented using magnetic resonance imaging (MRI). A patient with a long history of alcoholism developed a gait disturbance with involuntary movements at the lower extremities. MRI scans taken at the onset showed no particular abnormalities. He progressed to a coma 10 days later. MRI scans taken 20 days after the onset showed a focal lesion at the genu of the corpus callosum and he was diagnosed as having MBD. In addition, multiple lesions were observed in bilateral frontoparietal subcortical white matter. These lesions demonstrated similar intense MRI signals as the corpus callosum.

  19. A critical re-examination of sexual dimorphism in the corpus callosum microstructure

    DEFF Research Database (Denmark)

    Westerhausen, René; Kompus, Kristiina; Dramsdahl, Margaretha

    2011-01-01

    Recent diffusion-tensor imaging (DTI) studies suggest sexual dimorphism in the micro-structural architecture of the corpus callosum. However, the corpus callosum is also found to be larger in males than in females, a fact that might introduce a systematic bias to the analysis of DTI parameters. D...... the diffusion parameters did not correlate with regional callosal size. The present results indicate a stronger inter-hemispheric connectivity between the frontal lobes in males than females, which might be related to sex differences in hemispheric asymmetry and brain size....

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

    Science.gov (United States)

    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…

  1. Corpus callosum dysgenesis and lipoma: embryologic and magnetic resonance imaging aspects; Disgenesia do corpo caloso e lipoma: consideracoes embriologicas basicas e aspectos de imagem a ressonancia magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Abreu Junior, Luiz de; Borri, Maria Lucia; Wolosker, Angela Maria Borri; Hartmann, Luiz Guilherme de Carvalho; Galvao Filho, Mario de Melo [Hospital e Maternidade Sao Luiz, Sao Paulo, SP (Brazil). Setor de Diagnostico por Imagem]. E-mail: abreujr@directnet.com.br; D' Ippolito, Giuseppe [Hospital e Maternidade Sao Luiz, Sao Paulo, SP (Brazil). Setor de US/TC/RMN

    2005-07-15

    The corpus callosum is the major system of association fibers that permits communication of both cerebral hemispheres. Magnetic resonance imaging has improved the study of brain malformations, including the corpus callosum dysgenesis. Lipoma is a common finding in the spectrum of corpus callosum dysgenesis. The purpose of these study was to review the embryologic events and the magnetic resonance imaging aspects related to the corpus callosum dysgenesis and to the formation of the related lipoma. (author)

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

    Directory of Open Access Journals (Sweden)

    Jomol Sara John

    2013-01-01

    Full Text Available 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.

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

    Science.gov (United States)

    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.

  4. Changes caused by hydrocephalus, induced by kaolin, in the corpus callosum of adult dogs.

    Science.gov (United States)

    Cardoso, Edvaldo José Rodrigues; Lachat, João José; Lopes, Luiza Silva; Santos, Antonio Carlos dos; Colli, Benedicto Oscar

    2011-01-01

    To analyze the ventricular enlargement and myelination of the corpus callosum in adult dogs after four and eight weeks of kaolin-induction of hydrocephalus. 36 dogs were randomly divided into 3 groups: 1 - without hydrocephalus, 2 - kaolin-induction of hydrocephalus until the fourth week, and 3 - kaolin-induction of hydrocephalus until the eighth week. Ventricular ratios and volumes were calculated using magnetic resonance images, and myelination of the corpus callosum were histologically evaluated using solocromo-cianin stain. Radiological hydrocephalus was observed in 93.75% and overall mortality was 38.4%. Ventricular volumes and ratios were higher in groups 2 and 3 compared to group 1 and similar when measures in the fourth and eighth weeks were compared in the group 3. Indices of luminescence in the knee and in the splenium of the corpus callosum were higher in group 2 than in group 1 indicating that there was loss of myelin in group 2, and similar in groups 1 and 3, showing a tendency to remyelination after 8 weeks. The corpus callosum of dogs with kaolin-induced hydrocephalus responds with demyelination of the knee and splenium by the fourth week with a tendency to remyelination by the eighth week.

  5. Autism and Hypoplastic Corpus Callosum in a Case of Monocentric Marker Chromosome 15

    NARCIS (Netherlands)

    Jovanovic-Privrodski, Jadranka D.; Kavecan, Ivana I.; Obrenovic, Milan R.; Buonadonna, Lucia A.; Bukvic, Nenad M.

    2009-01-01

    An 8-year-old boy was diagnosed with autism, along with development delay, seizures, and hypoplastic corpus callosum. His karyotype was 47, XY, +mar.ish (15) (D15Z1+, SNRPN+, GABRB3+, PML-(de novo?). The supernumerary marker chromosome 15 with euchromatin was monosatellited and monocentric. Although

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

    Directory of Open Access Journals (Sweden)

    Lassonde Maryse

    2006-06-01

    Full Text Available Abstract 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.

  7. Involvement of corpus callosum in amyotrophic lateral sclerosis shown by MRI

    Energy Technology Data Exchange (ETDEWEB)

    Zandijcke, M. van [Dept. of Neurology, Bruges (Belgium); Casselman, J. [Dept. of Medical Imaging, Bruges (Belgium)

    1995-05-01

    Abnormal high signal in the corticospinal tracts on MRI has been described in amyotrophic lateral sclerosis. We report a case with further high signal in fibres of the corpus callosum on proton density and T2-weighted spin-echo images, closely matching findings of earlier pathological reports. (orig.)

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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…

  10. MRI Findings of Coexistence of Ectopic Neurohypophysis, Corpus Callosum Dysgenesis, and Periventricular Neuronal Heterotopia

    Directory of Open Access Journals (Sweden)

    Harun Arslan

    2014-01-01

    Full Text Available Ectopic neurohypophysis is a pituitary gland abnormality, which can accompany growth hormone deficiency associated with dwarfism. Here we present magnetic resonance imaging (MRI findings of a rare case of ectopic neurohypophysis, corpus callosum dysgenesis, and periventricular neuronal heterotopia coexisting, with a review of the literature.

  11. Transient Splenial Lesion of the Corpus Callosum Related to Migraine with Aura in a Pediatric Patient.

    Science.gov (United States)

    Ünver, Olcay; Kutlubay, Büşra; Besci, Tolga; Ekinci, Gazanfer; Baltacıoğlu, Feyyaz; Türkdoğan, Dilşad

    Transient splenial lesions of the corpus callosum are rare radiological findings first described in association with epilepsy, antiepileptic drugs and viral encephalitis. However, subsequently more cases were described associated with diverse clinical conditions. We describe a 13-year-old girl suffering from migraine with aura presenting with headache, right-sided hemiparesis and encephalopathy. Brain magnetic resonance imaging revealed an ovoid lesion in the splenium of the corpus callosum. The patient's neurological symptoms resolved within 3 days without therapy and the lesion disappeared in follow up magnetic resonance images obtained 3 weeks after the onset of the symptoms. Migraine with aura was considered to be the cause of the lesion. To our knowledge the present case is the first report of a pediatric patient with a diagnosis of migraine with aura presenting with hemiparesis and encephalopathy. A diagnosis of transient lesion of the corpus callosum should be suspected in patients with migraine with aura presenting with hemiparesis and encephalopathy. A mild course and a good prognosis might be expected in the presence of a splenial lesion of the corpus callosum.

  12. Transient Splenial Lesion of the Corpus Callosum Related to Migraine with Aura in a Pediatric Patient

    Directory of Open Access Journals (Sweden)

    Olcay Ünver

    2016-08-01

    Full Text Available Background: Transient splenial lesions of the corpus callosum are rare radiological findings first described in association with epilepsy, antiepileptic drugs and viral encephalitis. However, subsequently more cases were described associated with diverse clinical conditions. Case report: We describe a 13-year-old girl suffering from migraine with aura presenting with headache, right-sided hemiparesis and encephalopathy. Brain magnetic resonance imaging revealed an ovoid lesion in the splenium of the corpus callosum. The patient’s neurological symptoms resolved within 3 days without therapy and the lesion disappeared in follow up magnetic resonance images obtained 3 weeks after the onset of the symptoms. Results: Migraine with aura was considered to be the cause of the lesion. To our knowledge the present case is the first report of a pediatric patient with a diagnosis of migraine with aura presenting with hemiparesis and encephalopathy. Conclusions: A diagnosis of transient lesion of the corpus callosum should be suspected in patients with migraine with aura presenting with hemiparesis and encephalopathy. A mild course and a good prognosis might be expected in the presence of a splenial lesion of the corpus callosum.

  13. Corpus Callosum Analysis using MDL-based Sequential Models of Shape and Appearance

    DEFF Research Database (Denmark)

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

    2004-01-01

    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 ar...

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

    Science.gov (United States)

    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.

  15. Age at developmental cortical injury differentially Alters corpus callosum volume in the rat

    Directory of Open Access Journals (Sweden)

    Rosen Glenn D

    2007-11-01

    Full Text Available Abstract Background Freezing lesions to developing rat cortex induced between postnatal day (P one and three (P1 – 3 lead to malformations similar to human microgyria, and further correspond to reductions in brain weight and cortical volume. In contrast, comparable lesions on P5 do not produce microgyric malformations, nor the changes in brain weight seen with microgyria. However, injury occurring at all three ages does lead to rapid auditory processing deficits as measured in the juvenile period. Interestingly, these deficits persist into adulthood only in the P1 lesion case 1. Given prior evidence that early focal cortical lesions induce abnormalities in cortical morphology and connectivity 1234, we hypothesized that the differential behavioral effects of focal cortical lesions on P1, P3 or P5 may be associated with underlying neuroanatomical changes that are sensitive to timing of injury. Clinical studies indicate that humans with perinatal brain injury often show regional reductions in corpus callosum size and abnormal symmetry, which frequently correspond to learning impairments 567. Therefore, in the current study the brains of P1, 3 or 5 lesion rats, previously evaluated for brain weight, and cortical volume changes and auditory processing impairments (P21-90, were further analyzed for changes in corpus callosum volume. Results Results showed a significant main effect of Treatment on corpus callosum volume [F (1,57 = 10.2, P Conclusion Decrements in corpus callosum volume in the P1 and 3 lesion groups are consistent with the reductions in brain weight and cortical volume previously reported for microgyric rats 18. Current results suggest that disruption to the cortical plate during early postnatal development may lead to more widely dispersed neurovolumetric anomalies and subsequent behavioral impairments 1, compared with injury that occurs later in development. Further, these results suggest that in a human clinical setting decreased

  16. Corpus callosum thickness on mid-sagittal MRI as a marker of brain volume: a pilot study in children with HIV-related brain disease and controls

    Energy Technology Data Exchange (ETDEWEB)

    Andronikou, Savvas [University of the Witwatersrand, Department of Radiology, Faculty of Health Sciences, Cape Town (South Africa); Ackermann, Christelle [University of Stellenbosch, Department of Radiology, Stellenbosch (South Africa); Laughton, Barbara; Cotton, Mark [Stellenbosch University and Tygerberg Children' s Hospital, Children' s Infectious Diseases Research Unit, Stellenbosch (South Africa); Tomazos, Nicollette [University of Cape Town, Faculty of Commerce, Department of Management Studies, Cape Town (South Africa); Spottiswoode, Bruce [University of Cape Town, MRC/UCT Medical Imaging Research Unit, Department of Human Biology, Cape Town (South Africa); Mauff, Katya [University of Cape Town, Department of Statistical Sciences, Cape Town (South Africa); Pettifor, John M. [University of the Witwatersrand, MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics, Faculty of Health Sciences, Witwatersrand (South Africa)

    2015-07-15

    Corpus callosum thickness measurement on mid-sagittal MRI may be a surrogate marker of brain volume. This is important for evaluation of diseases causing brain volume gain or loss, such as HIV-related brain disease and HIV encephalopathy. To determine if thickness of the corpus callosum on mid-sagittal MRI is a surrogate marker of brain volume in children with HIV-related brain disease and in controls without HIV. A retrospective MRI analysis in children (<5 years old) with HIV-related brain disease and controls used a custom-developed semi-automated tool, which divided the midline corpus callosum and measured its thickness in multiple locations. Brain volume was determined using volumetric analysis. Overall corpus callosum thickness and thickness of segments of the corpus callosum were correlated with overall and segmented (grey and white matter) brain volume. Forty-four children (33 HIV-infected patients and 11 controls) were included. Significant correlations included overall corpus callosum (mean) and total brain volume (P = 0.05); prefrontal corpus callosum maximum with white matter volume (P = 0.02); premotor corpus callosum mean with total brain volume (P = 0.04) and white matter volume (P = 0.02), premotor corpus callosum maximum with white matter volume (P = 0.02) and sensory corpus callosum mean with total brain volume (P = 0.02). Corpus callosum thickness correlates with brain volume both in HIV-infected patients and controls. (orig.)

  17. Tracking the Functional Development of the Corpus Callosum in Children Using Behavioral and Evoked Potential Interhemispheric Transfer Times.

    Science.gov (United States)

    Meissner, Tobias W; Friedrich, Patrick; Ocklenburg, Sebastian; Genç, Erhan; Weigelt, Sarah

    2017-01-01

    Visual functions requiring interhemispheric transfer exhibit a long developmental trajectory up to age 12, which might be constrained by corpus callosum maturation. Here, we use electrophysiological and behavioral crossed-uncrossed differences (CUDs) in a visual Poffenberger paradigm to estimate the interhemispheric transfer time (IHTT)-a measure of corpus callosum maturation-in 7-year-old children and adults. Adults' electrophysiological CUDs were faster than 7-year-olds'. Behavioral CUDs did not differ and proved to be unreliable in a 6-month follow-up test. These findings suggest that the corpus callosum still undergoes development at the age of 7 that can only reliably be traced with neuroscientific methods.

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

    NARCIS (Netherlands)

    Vatta, F.; Mininel, S.; Colafati, G.S.; D'Errico, L.; Malena, S.; Di Salle, F.

    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

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

    NARCIS (Netherlands)

    Vatta, F.; Mininel, S.; Colafati, G.S.; D'Errico, L.; Malena, S.; Di Salle, F.

    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 (

  20. A case of corpus callosum agenesis presenting with recurrent brief depression

    Directory of Open Access Journals (Sweden)

    Bhattacharyya Ranjan

    2009-01-01

    Full Text Available Agenesis of corpus callosum can have various neuropsychiatric manifestations. Following case report highlights the case of a young man presenting with features of recurrent brief depressive disorder, each lasting for about 3 to 7 days, for over a year. He had history of occasional headache and episodes of swooning attack in between, usually precipitated by emotional events. His neuroimaging revealed agenesis of corpus callosum. He was experiencing swooning attacks as he became aware that some ′unusual′ findings were present in his reports. Recurrent brief depression can be a manifestation of this congenital anomaly, and conversion disorder can be present as comorbid diagnosis perhaps due to ignorance and fear of this apparently innocuous congenital malformation.

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

    Science.gov (United States)

    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. Copyright © 2014 by the American Society of Neuroimaging.

  2. Boomerang sign: Clinical significance of transient lesion in splenium of corpus callosum

    Directory of Open Access Journals (Sweden)

    Hardeep Singh Malhotra

    2012-01-01

    Full Text Available Transient signal abnormality in the splenium of corpus callosum on magnetic resonance imaging (MRI is occasionally encountered in clinical practice. It has been reported in various clinical conditions apart from patients with epilepsy. We describe 4 patients with different etiologies presenting with signal changes in the splenium of corpus callosum. They were diagnosed as having progressive myoclonic epilepsy (case 1, localization-related epilepsy (case 2, hemicrania continua (case 3, and postinfectious parkinsonism (case 4. While three patients had complete involvement of the splenium on diffusion-weighted image ("boomerang sign", the patient having hemicrania continua showed semilunar involvement ("mini-boomerang" on T2-weighted and FLAIR image. All the cases had noncontiguous involvement of the splenium. We herein, discuss these cases with transient splenial involvement and stress that such patients do not need aggressive diagnostic and therapeutic interventions. An attempt has been made to review the literature regarding the pathophysiology, etiology, and outcome of such lesions.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  5. [Cocaine and trisomy 8 associated with prenatal diagnosis of corpus callosum agenesis].

    Science.gov (United States)

    Gonzales, E; Caeymaex, L; Aboura, A; Vial, M; De Laveaucoupet, J; Labrune, P; Tachdjian, G

    2005-12-01

    We report the case of a newborn presenting an agenesis of corpus callosum (ACC) discovered in the prenatal period and initially related to cocaine exposure during the first trimester of gestation. The cytogenetic analysis revealed a trisomy 8 mosaicism. The putative role of prenatal cocaine exposure and mosaicism for chromosome 8 in ACC are discussed. This report emphasizes the specific analysis of chromosome 8 by using fluorescence in situ hybridization as a complement to routine cytogenetic analysis for prenatal diagnosis of ACC.

  6. One hundred million years of interhemispheric communication: the history of the corpus callosum

    Directory of Open Access Journals (Sweden)

    F. Aboitiz

    2003-04-01

    Full Text Available Analysis of regional corpus callosum fiber composition reveals that callosal regions connecting primary and secondary sensory areas tend to have higher proportions of coarse-diameter, highly myelinated fibers than callosal regions connecting so-called higher-order areas. This suggests that in primary/secondary sensory areas there are strong timing constraints for interhemispheric communication, which may be related to the process of midline fusion of the two sensory hemifields across the hemispheres. We postulate that the evolutionary origin of the corpus callosum in placental mammals is related to the mechanism of midline fusion in the sensory cortices, which only in mammals receive a topographically organized representation of the sensory surfaces. The early corpus callosum may have also served as a substrate for growth of fibers connecting higher-order areas, which possibly participated in the propagation of neuronal ensembles of synchronized activity between the hemispheres. However, as brains became much larger, the increasingly longer interhemispheric distance may have worked as a constraint for efficient callosal transmission. Callosal fiber composition tends to be quite uniform across species with different brain sizes, suggesting that the delay in callosal transmission is longer in bigger brains. There is only a small subset of large-diameter callosal fibers whose size increases with increasing interhemispheric distance. These limitations in interhemispheric connectivity may have favored the development of brain lateralization in some species like humans. "...if the currently received statements are correct, the appearance of the corpus callosum in the placental mammals is the greatest and most sudden modification exhibited by the brain in the whole series of vertebrated animals..." T.H. Huxley (1.

  7. Transient Splenial Lesion of the Corpus Callosum Related to Migraine with Aura in a Pediatric Patient

    OpenAIRE

    Olcay Ünver; Büşra Kutlubay; Tolga Besci; Gazanfer Ekinci; Feyyaz Baltacıoğlu; Dilşad Türkdoğan

    2016-01-01

    Background: Transient splenial lesions of the corpus callosum are rare radiological findings first described in association with epilepsy, antiepileptic drugs and viral encephalitis. However, subsequently more cases were described associated with diverse clinical conditions. Case report: We describe a 13-year-old girl suffering from migraine with aura presenting with headache, right-sided hemiparesis and encephalopathy. Brain magnetic resonance imaging revealed an ovoid lesion in the splenium...

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

    Science.gov (United States)

    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.

  9. Rubinstein-Taybi syndrome with agenesis of corpus callosum

    Directory of Open Access Journals (Sweden)

    Shubhankar Mishra

    2015-01-01

    Full Text Available 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  12. Reversible Restricted Diffusion in the Corpus Callosum in Various Pediatric Diseases

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    Kim, Won Kyung; Hong, Hyun Sook; Lee, A Leum; Cha, Jang Gyu; Lee, Hae Kyung [Dept. of Radiology, Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Bae, Won Kyung [Dept. of Radiology, Soonchunhyang University Cheonan Hospital, Soonchunhyang University College of Medicine, Cheonan (Korea, Republic of)

    2012-04-15

    To evaluate the reversible restricted diffusion in the corpus callosum in pediatric patients with clinical findings, and to discuss the possible pathogenesis of these lesions. Between 2007 and 2011, seven children with reversible signal abnormalities in the corpus callosum were identified and retrospectively reviewed. Diseases and conditions associated with lesions included: trauma (n = 3), neonatal seizure (n = 1), clinically suspected mild encephalopathy (n = 1), multiple sclerosis (n = 1), and seizure with subdural hygroma (n = 1). The callosal lesions were located in the splenium and the genu (n = 2), the splenium and the body (n = 1), and the splenium only (n 4). The shape of the lesions was round-to-ovoid (n = 4) or linear (n = 3). Follow-up MRI scans showed completely resolved (n = 6) or persistent (n = 1) signal abnormalities on diffusion-weighted imaging as well as apparent diffusion coefficient mapping. Clinical outcomes were good in six of the patents but poor in the seventh. Reversible restricted diffusion in the corpus callosum can develop in various diseases. Knowledge of the MRI findings and associated diseases might be helpful in predicting patients' conditions and clinical outcomes.

  13. Agenesis of the corpus callosum: classifying functional manifestations with the ICF-CY.

    Science.gov (United States)

    Kovac, Megan L; Simeonsson, Rune J

    2014-01-01

    Agenesis of the corpus callosum (ACC) is a congenital condition in which the corpus callosum fails to develop fully. In the literature, ACC has been broadly conceptualized and inconsistently described. This article demonstrates how the universal language of the International Classification of Functioning, Disability and Health-Children and Youth can increase the specificity with which researchers and clinicians describe the variable manifestations of ACC. The database for this article was based on a review of 83 studies on developmental and neuropsychological manifestations of congenital ACC in children and adolescents. First, the extent to which the findings on ACC could be documented using the taxonomic codes in the ICF-CY was examined. Next, the findings from each study were mapped onto the ICF-CY to summarize the distribution of clinical features reported in the literature. There was a high degree of correspondence between the reported findings and the taxonomic codes of the ICF-CY. The distribution of clinical features was discussed. This taxonomic application advances the ICF-CY as a common language for researchers and clinicians who work with children who have ACC. Implications for Rehabilitation Agenesis of the corpus callosum (ACC) is a condition that has been broadly conceptualized and inconsistently described in research and practice. The variable clinical manifestations of children with ACC can be most effectively described using the ICF-CY. The application of the ICF-CY to conditions with highly variable clinical manifestations, like ACC, positively impacts research and practice.

  14. Functional topography of the corpus callosum investigated by DTI and f MRI

    Institute of Scientific and Technical Information of China (English)

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

    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(f MRI), 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, f MRI has been the key technique in documenting the activation of white matter fibers, particularly in the corpus callosum. By combining DTT and f MRI 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 f MRI activation. Altogether such findings lend further support to the notion that the corpus callosum displays a functional topographic organization that can be explored with f MRI.

  15. [Pediatric neurofunctional intervention in agenesis of the corpus callosum: a case report].

    Science.gov (United States)

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

    2014-09-01

    To describe a clinical report pre- and post-neurofunctional intervention in a case of agenesis of the corpus callosum. 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. 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 training reactions, influenced the acquisition of a more selective motor behavior. Copyright © 2014 Sociedade de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

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

    Science.gov (United States)

    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

  17. A semi-automated method for measuring thickness and white matter integrity of the corpus callosum

    Directory of Open Access Journals (Sweden)

    S Andronikou

    2012-12-01

    Full Text Available Aim. Diseases affecting cerebral white matter may lead to left-right asymmetries and atrophy of interhemispheric connections, i.e. the corpus callosum (CC. Our aim was to describe and test a semi-automated system that divides the midline CC into a number of segments and determines thickness at each, then performs fibre tracking from these segments. Methods. Six normal female volunteers (average age 25.8 ±6.7 years and a female patient with diagnosed multiple sclerosis (age 26 years were scanned on a 3T MRI. We performed diffusion-weighted imaging in 12 directions, and calculated diffusion tensors and fractional anisotropy (FA maps from this pre-processed data. Fibre tracking from a region-of-interest encompassing the entire CC was done. This fibre data, together with FA maps and the unweighted diffusion tensor imaging (DTI image (b = 0 s/mm2, were imported into a custom tool written in MATLAB. The midline sagittal position was carefully defined by selecting multiple midline points in coronal and axial views and rotating the image volume and fibre co-ordinates accordingly. Using the customised tool, dorsal and ventral CC contours were manually drawn on the mid-sagittal FA image, initiating automated calculation of a contour midway between these manually drawn lines. The programme was designed to then divide the midline contour into a pre-selected number of segments; from each segment border, perpendicular spokes were projected until they intersected with the dorsal and ventral contours. This technique divided the CC into a pre-set amount of segments, the number of which was limited by the spatial resolution. It was decided to set the number at 40 to ensure that each segment depicted a contiguous strip of voxels across the CC from the dorsal to the ventral contour. The system allows these segments to then be used as seeds for separate fibre tracking in each cerebral hemisphere, and various parameters are automatically plotted as a function of

  18. PSYCHO-MOTRIC REHABILITATION IN CHILDREN WITH AGENESIS OF CORPUS CALLOSUM (Case study

    Directory of Open Access Journals (Sweden)

    Zărnica I. Manuela Mirela

    2011-12-01

    Full Text Available Agenesis of corpus callosum is a new challenge for the puluridisciplinary team, in their efforts for the rehabilitation of childrens with this diagnose, because is a rare congenital desease with an unknown frequence of emergence. Scope. This paperwork aims to present the approach modalities of the child with agenesis of corpus callousum and the means of physical therapy that may help. Methods. This is a case study of a 5 years old girl with asenesis of corpus callosum. For assessment we used motor assessment, range of motion, reflexes. Exercises from different positions were done as games and motric songs. Sensory stimulation was also done. Rezults. By direct observation of the patient we observed significant improvement in motor function. We also foud unexpected improvement of quiet stance and dynamic balance, sensory-motor coordination. Conclusions. Game, tha main therapeutic method through its form, diversity and characteristics - atractivity, directness, creativity, movement freedom – is the main supplement of child psicho-motric development. A balanced distribution of influences upon motricity, psychic, thinking and action, nonverbal and expression language, represent the qualitative peculiarity of specialist’s and parents efforts.

  19. Microstructural damage of the posterior corpus callosum contributes to the clinical severity of neglect.

    Directory of Open Access Journals (Sweden)

    Marco Bozzali

    Full Text Available One theory to account for neglect symptoms in patients with right focal damage invokes a release of inhibition of the right parietal cortex over the left parieto-frontal circuits, by disconnection mechanism. This theory is supported by transcranial magnetic stimulation studies showing the existence of asymmetric inhibitory interactions between the left and right posterior parietal cortex, with a right hemispheric advantage. These inhibitory mechanisms are mediated by direct transcallosal projections located in the posterior portions of the corpus callosum. The current study, using diffusion imaging and tract-based spatial statistics (TBSS, aims at assessing, in a data-driven fashion, the contribution of structural disconnection between hemispheres in determining the presence and severity of neglect. Eleven patients with right acute stroke and 11 healthy matched controls underwent MRI at 3T, including diffusion imaging, and T1-weighted volumes. TBSS was modified to account for the presence of the lesion and used to assess the presence and extension of changes in diffusion indices of microscopic white matter integrity in the left hemisphere of patients compared to controls, and to investigate, by correlation analysis, whether this damage might account for the presence and severity of patients' neglect, as assessed by the Behavioural Inattention Test (BIT. None of the patients had any macroscopic abnormality in the left hemisphere; however, 3 cases were discarded due to image artefacts in the MRI data. Conversely, TBSS analysis revealed widespread changes in diffusion indices in most of their left hemisphere tracts, with a predominant involvement of the corpus callosum and its projections on the parietal white matter. A region of association between patients' scores at BIT and brain FA values was found in the posterior part of the corpus callosum. This study strongly supports the hypothesis of a major role of structural disconnection between the

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

    Science.gov (United States)

    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. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

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

    Science.gov (United States)

    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.

  2. Gorlin's syndrome with a thin corpus callosum and a third ventricular cyst

    Energy Technology Data Exchange (ETDEWEB)

    Kantarci, M.; Alper, F.; Onbas, O. [Department of Radiology, Atatuerk University School of Medicine, Erzurum (Turkey); Ertas, U. [Department of Oral and Maxillofacial Surgery, Atatuerk University School of Dentist, Erzurum (Turkey); Sutbeyaz, Y.; Karasen, R.M. [Otolaryngology, Atatuerk University School of Medicine, Otolaryngology, Erzurum (Turkey)

    2003-06-01

    Gorlin's syndrome (naevoid basal cell carcinoma) is an autosomal dominant tumor-predisposition syndrome, classically consists of multiple basal cell carcinomas of the skin, odontogenic keratocyst of the jaw, various skeletal abnormalities, and lamellar falx calcifications. Many associated lesions have been reported. We report a case of Gorlin's syndrome in a 22-year-old man in whom CT and MR images showed unusual findings of the thin corpus callosum and third ventricular cyst. We present a case of this syndrome with special emphasis on its unusual neuroradiological findings and radiological management. (orig.)

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

    Science.gov (United States)

    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.

  4. Neuromyelitis optica with linear enhancement of corpus callosum in brain magnetic resonance imaging with contrast: a case report.

    Science.gov (United States)

    Sahraian, Mohammad Ali; Moghadasi, Abdorreza Naser; Owji, Mahsa; Naghshineh, Hoda; Minagar, Alireza

    2015-06-10

    Neuromyelitis optica is a demyelinating disease of the central nervous system with various patterns of brain lesions. Corpus callosum may be involved in both multiple sclerosis and neuromyelitis optica. Previous case reports have demonstrated that callosal lesions in neuromyelitis optica are usually large and edematous and have a heterogeneous intensity showing a "marbled pattern" in the acute phase. Their size and intensity may reduce with time or disappear in the chronic stages. In this report, we describe a case of a 25-year-old Caucasian man with neuromyelitis optica who presented clinically with optic neuritis and myelitis. His brain magnetic resonance imaging demonstrated linear enhancement of the corpus callosum. Brain images with contrast agent added also showed linear ependymal layer enhancement of the lateral ventricles, which has been reported in this disease previously. Linear enhancement of corpus callosum in magnetic resonance imaging with contrast agent could help in diagnosing neuromyelitis optica and differentiating it from other demyelinating disease, especially multiple sclerosis.

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

    DEFF Research Database (Denmark)

    Hansen, Christina Halgren; Kjaergaard, S; Bak, M

    2011-01-01

    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......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...... 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...

  6. Quantitative analysis of the corpus callosum in children with cerebral palsy and developmental delay: correlation with cerebral white matter volume

    Energy Technology Data Exchange (ETDEWEB)

    Panigrahy, Ashok [Childrens Hospital Los Angeles, Department of Radiology, Los Angeles, CA (United States); Barnes, Patrick D. [Stanford University Medical Center, Department of Radiology, Lucile Salter Packard Children' s Hospital, Palo Alto, CA (United States); Robertson, Robert L. [Children' s Hospital Boston, Department of Radiology, Boston, MA (United States); Sleeper, Lynn A. [New England Research Institute, Watertown, MA (United States); Sayre, James W. [UCLA Medical Center, Departments of Radiology and Biostatistics, Los Angeles, CA (United States)

    2005-12-01

    This study was conducted to quantitatively correlate the thickness of the corpus callosum with the volume of cerebral white matter in children with cerebral palsy and developmental delay. Material and methods: A clinical database of 70 children with cerebral palsy and developmental delay was established with children between the ages of 1 and 5 years. These children also demonstrated abnormal periventricular T2 hyperintensities associated with and without ventriculomegaly. Mid-sagittal T1-weighted images were used to measure the thickness (genu, mid-body, and splenium) and length of the corpus callosum. Volumes of interest were digitized based on gray-scale densities to define the hemispheric cerebral white matter on axial T2-weighted and FLAIR images. The thickness of the mid-body of the corpus callosum was correlated with cerebral white matter volume. Subgroup analysis was also performed to examine the relationship of this correlation with both gestational age and neuromotor outcome. Statistical analysis was performed using analysis of variance and Pearson correlation coefficients. There was a positive correlation between the thickness of the mid-body of the corpus callosum and the volume of cerebral white matter across all children studied (R=0.665, P=0.0001). This correlation was not dependent on gestational age. The thickness of the mid-body of the corpus callosum was decreased in the spastic diplegia group compared to the two other groups (hypotonia and developmental delay only; P<0.0001). Within each neuromotor subgroup, there was a positive correlation between thickness of the mid-body of the corpus callosum and volume of the cerebral white matter. (orig.)

  7. Genetic, morphometric, and behavioral factors linked to the midsagittal area of the corpus callosum

    Directory of Open Access Journals (Sweden)

    Alex J Newbury

    2012-05-01

    Full Text Available TThe corpus callosum is the main commissure connecting left and right cerebral hemispheres, and varies widely in size. Differences in the midsagittal area of the corpus callosum (MSACC have been associated with a number of cognitive and behavioral phenotypes, including obsessive-compulsive disorders, psychopathy, suicidal tendencies, bipolar disorder, schizophrenia, autism, and attention deficit hyperactivity disorder. Although there is evidence to suggest that MSACC is heritable in normal human populations, there is surprisingly little evidence concerning the genetic modulation of this variation. Mice provide a potentially ideal tool to dissect the genetic modulation of MSACC. Here, we use a large genetic reference panel—the BXD recombinant inbred (RI line—to dissect the natural variation of the MSACC. We estimated the MSACC in over 300 individuals from nearly 80 strains. We found a 4-fold difference in MSACC between individual mice, and a 2.5 fold difference between strains. MSACC is a highly heritable trait (h2 = 0.60, and we mapped a suggestive QTL to the distal portion of Chr 14. Using sequence data and neocortical expression databases, we were able to identify eight positional and plausible biological candidate genes within this interval. Finally, we found that MSACC correlated with behavioral traits associated with anxiety and attention.

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

    Science.gov (United States)

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

    2011-04-30

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

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

    Science.gov (United States)

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

    2009-02-01

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

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

    Science.gov (United States)

    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

  11. Structural and functional reorganization of the corpus callosum between the age of 6 and 8 years.

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

    2011-05-01

    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.

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

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    Marta Pietrasanta

    2012-01-01

    Full Text Available 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.

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

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

    2016-08-01

    Joubert syndrome (JS) is a clinically and genetically heterogeneous ciliopathy characterized by episodic hyperpnea and apnea, hypotonia, ataxia, cognitive impairment and ocular motor apraxia. The "molar tooth sign" is pathognomonic of this condition. Mutations in the MKS1 gene are a major cause of Meckel-Gruber syndrome (MKS), the most common form of syndromic neural tube defects, frequently resulting in perinatal lethality. We present the phenotype and genotype of a child with severe JS and agenesis of the corpus callosum (ACC). In our patient, a next generation sequencing (NGS) approach revealed the following two variants of the MKS1 gene: first, a novel missense variant [ c.240G > T (p.Trp80Cys)], which affects a residue that is evolutionarily highly conserved in mammals and ciliates; second, a 29 bp deletion in intron 15 [c.1408-35_1408-7del29], a founder mutation, which in a homozygous state constitutes the major cause of MKS in Finland. We review the MKS1-variants in all of the eleven JS patients reported to date and compare these patients to our case. To our knowledge, this is the first patient with Joubert syndrome and agenesis of the corpus callosum where a potentially causal genotype is provided. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  14. Value of brain MRI when sonography raises suspicion of agenesis of the corpus callosum in fetuses.

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    Jarre, A; Llorens Salvador, R; Montoliu Fornas, G; Montoya Filardi, A

    To evaluate the role of magnetic resonance imaging (MRI) in fetuses with a previous sonographic suspicion of agenesis of the corpus callosum (ACC) to confirm the diagnosis and to detect associated intracranial anomalies. Single-center retrospective and descriptive observational study of the brain MRI performed in 78 fetuses with ACC sonographic suspicion between January 2006 and December 2015. Two experts in fetal imaging reviewed the MRI findings to evaluate the presence and morphology of the corpus callosum. When ACC was detected the whole fetal brain anatomy was thoroughly studied to determine the presence of associated anomalies. Prenatal MR imaging findings were compared to postnatal brain MRI or necropsy findings when available. Fetal MRI diagnosed 45 cases of ACC, 12 were partial (26.7%) and 33 complete (73.3%). In 28 cases (62,2%) associated intracranial anomalies were identified. The most often abnormality was ventriculomegaly (78,6%), followed by cortical malformations (53,6%), posterior fossa (25%) and midline anomalies (10,7%). Fetal brain MRI has an important role in the diagnosis of ACC and detection of associated anomalies. To perform a fetal brain MRI is important in fetuses with sonographic suspicion of ACC. Copyright © 2017 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

  15. Agenesis of the Corpus Callosum and Skeletal Deformities in Two Unrelated Patients: Analysis via MRI and Radiography

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    Ali Al Kaissi

    2014-01-01

    Full Text Available Purpose. Mental retardation, mild to severe epilepsy and cerebral palsy often of hemiplegic type are common accompaniments in patients with agenesis/hypoplasia of the corpus callosum. Skeletal deformities of bilateral radiohumeral synostosis, brachydactyly, bilateral elbow dislocation, talipes equinovarus, and juxtacalcaneal accessory bones have been encountered in two unrelated children with agenesis of the corpus callosum. Methods. We report on two unrelated children who presented with the full clinical criteria of agenesis of the corpus callosum. Strikingly, both presented with variable upper and lower limb deformities. The clinical features, radiographic and MRI findings in our current patients, have been compared with previously reported cases identified through a PubMed literature review. Results. Bilateral radiohumeral synostosis associated with pyruvate dehydrogenase deficiency has been encountered in one patient. The other patient manifested bilateral elbow dislocation, coxa valga, talipes equinovarus, and bilateral juxtacalcaneal accessory bones. Conclusion. The constellation of malformation complexes in our current patients have the hitherto not been reported and expanding the spectrum of skeletal deformities in connection with agenesis of the corpus callosum.

  16. The corpus callosum, the other great forebrain commissures, and the septum pellucidum: anatomy, development, and malformation

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    Raybaud, Charles [Division of Neuroradiology, Hospital for Sick Children, Toronto, ON (Canada); University of Toronto, Division of Radiology, Toronto, ON (Canada)

    2010-06-15

    There are three telencephalic commissures which are paleocortical (the anterior commissure), archicortical (the hippocampal commissure), and neocortical. In non-placental mammals, the neocortical commissural fibers cross the midline together with the anterior and possibly the hippocampal commissure, across the lamina reuniens (joining plate) in the upper part of the lamina terminalis. In placental mammals, a phylogenetically new feature emerged, which is the corpus callosum: it results from an interhemispheric fusion line with specialized groups of mildline glial cells channeling the commissural axons through the interhemispheric meninges toward the contralateral hemispheres. This concerns the frontal lobe mainly however: commissural fibers from the temporo-occipital neocortex still use the anterior commissure to cross, and the posterior occipito-parietal fibers use the hippocampal commissure, forming the splenium in the process. The anterior callosum and the splenium fuse secondarily to form the complete commissural plate. Given the complexity of the processes involved, commissural ageneses are many and usually associated with other diverse defects. They may be due to a failure of the white matter to develop or to the commissural neurons to form or to migrate, to a global failure of the midline crossing processes or to a selective failure of commissuration affecting specific commissural sites (anterior or hippocampal commissures, anterior callosum), or specific sets of commissural axons (paleocortical, hippocampal, neocortical commissural axons). Severe hemispheric dysplasia may prevent the axons from reaching the midline on one or both sides. Besides the intrinsically neural defects, midline meningeal factors may prevent the commissuration as well (interhemispheric cysts or lipoma). As a consequence, commissural agenesis is a malformative feature, not a malformation by itself. Good knowledge of the modern embryological data may allow for a good understanding of a

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

    DEFF Research Database (Denmark)

    Plessen, Kerstin J; Grüner, Renate; Lundervold, Arvid

    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...... interhemispheric fibers or reduced axonal myelination. FA values did not correlate significantly with the severity of tic symptoms. Group differences in measures of connectivity did not seem to be attributable to the presence of comorbid ADHD or OCD, to medication exposure, or group differences in IQ. CONCLUSION......: Our findings of a reduced interhemispheral white matter connectivity add to the understanding of neural connectivity and plasticity in the brains of children who have TS....

  18. Neurophysiological investigation of congenital mirror movements in a patient with agenesis of the corpus callosum.

    Science.gov (United States)

    Lepage, Jean-François; Beaulé, Vincent; Srour, Myriam; Rouleau, Guy; Pascual-Leone, Alvaro; Lassonde, Maryse; Théoret, Hugo

    2012-04-01

    We describe a patient with complete agenesis of the corpus callosum and congenital mirror movements in which primary motor cortex (M1) excitability of both hemispheres was assessed with transcranial magnetic stimulation. Voluntary contraction of the index finger was associated with bilateral electromyographic activity in the first dorsal interosseus muscle. Motor-evoked potentials of identical latencies were produced bilaterally after unilateral M1 stimulation. Measures of intracortical inhibition and facilitation were within normal limits bilaterally although a shorter contralateral silent period was found for both hemispheres. Taken together, the current data suggest a pattern of M1 excitability very similar to that found in patients with congenital mirror movements and no other motor abnormality. Copyright © 2012 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

    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.

  20. Splenial lesions of the corpus callosum: Disease Spectrum and MRI findings

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    Park, Sung Eun; Choi, Dae Seob; Shin, Hwa Seon; Baek, Hye Jin; Choi, Ho Cheol; Kim, Ji Eun; Choi, Hye Young; Park, Min Jung [Dept. of Radiology, Gyeongsang National University School of Medicine, Jinju (Korea, Republic of)

    2017-08-01

    The corpus callosum (CC) is the largest white matter structure in the brain, consisting of more than 200–250 million axons that provide a large connection mainly between homologous cerebral cortical areas in mirror image sites. The posterior end of the CC is the thickest part, which is called the slenium. Various diseases including congenital to acquired lesions including congenital anomalies, traumatic lesions, ischemic diseases, tumors, metabolic, toxic, degenerative, and demyelinating diseases, can involve the splenium of the CC and their clinical symptoms and signs are also variable. Therefore, knowledge of the disease entities and the imaging findings of lesions involving the splenium is valuable in clinical practice. MR imaging is useful for the detection and differential diagnosis of splenial lesions of the CC. In this study, we classify the disease entities and describe imaging findings of lesions involving the splenium of the CC based on our experiences and a review of the literature.

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

    Science.gov (United States)

    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.

  2. The role of corpus callosum development in functional connectivity and cognitive processing.

    Directory of Open Access Journals (Sweden)

    Leighton B N Hinkley

    Full Text Available 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

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

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    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.

  4. Assessing corpus callosum changes in Alzheimer's disease: comparison between tract-based spatial statistics and atlas-based tractography.

    Directory of Open Access Journals (Sweden)

    Maria Giulia Preti

    Full Text Available Tractography based on Diffusion Tensor Imaging (DTI represents a valuable tool for investigating brain white matter (WM microstructure, allowing the computation of damage-related diffusion parameters such as Fractional Anisotropy (FA in specific WM tracts. This technique appears relevant in the study of pathologies in which brain disconnection plays a major role, such as, for instance, Alzheimer's Disease (AD. Previous DTI studies have reported inconsistent results in defining WM abnormalities in AD and in its prodromal stage (i.e., amnestic Mild Cognitive Impairment; aMCI, especially when investigating the corpus callosum (CC. A reason for these inconsistencies is the use of different processing techniques, which may strongly influence the results. The aim of the current study was to compare a novel atlas-based tractography approach, that sub-divides the CC in eight portions, with Tract-Based Spatial Statistics (TBSS when used to detect specific patterns of CC FA in AD at different clinical stages. FA data were obtained from 76 subjects (37 with mild AD, 19 with aMCI and 20 elderly healthy controls, HC and analyzed using both methods. Consistent results were obtained for the two methods, concerning the comparisons AD vs. HC (significantly reduced FA in the whole CC of AD patients and AD vs. aMCI (significantly reduced FA in the frontal portions of the CC in AD patients, thus identifying a relative preservation of the frontal CC regions in aMCI patients compared to AD. Conversely, the atlas-based method but not the TBSS showed the ability to detect a selective FA change in the CC parietal, left temporal and occipital regions of aMCI patients compared to HC. This finding indicates that an analysis including a higher number of voxels (with no restriction to tract skeletons may detect characteristic pattern of FA in the CC of patients with preclinical AD, when brain atrophy is still modest.

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

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    Muhammad SAEED*

    2014-12-01

    Full Text Available How to Cite This Article: Saeed M, Haq A, Qadir Kh.Bart’s Syndrome Associated Corpus Callosum Agenesis and Choanal Atresia. Iran J Child Neurol. 2014 Autumn;8(4: 76-79.AbstractObjectiveBart’s syndrome is defined as congenital localized absence of skin, and associated with epidermolysis bullosa. A newborn with Bart’s syndrome is reported because it is a very rare condition, especially when associated with corpus callosum agenesis and concomitant choanal atresia. Clinically it is characterized by raw beefy areas of denuded skin mainly on hands and feet.We report a rare case of a term female newborn born to non-consanguineous parents who presented with congenital absence of skin in, face, trunk and extremities. To the best of our knowledge, this is the first report presenting a case of Bart’s syndrome associated with corpus callosum agenesis.ReferencesBart BJ, Garlin RJ, Anderson VE, Lynch FW. Congenital localized absence of skin and associated abnormalities resembling epidermolysis bullosa. A new syndrome. Arch Dermatol 1966; 93: 296-304.Bart BJ. Epidermolysis bullosa and congenital localized absence of skin. Arch Dermatol 1970; 101: 78-81.Skoven I, Drzewiecki KT. Congenital localized skin defect and epidermolysis bullosa hereditaria letalis. Acta Derm Venereol 1979; 59: 533-537.Wojnarowska FT, Eady RA, Wells RS. Dystrophic epidermolysis bullosa presenting with congenital localized absence of skin: report of four cases. Br J Dermatol 1983; 108: 477-483.Kanzler MH, Smoller B, Woodley DT. Congenital localized absence of the skin as a manifestation of epidermolysis bullosa. Arch Dermatol 1992; 128:1087-90.Maman E, Maor E, Kachko L, Carmi R. Epidermolysis bullosa, pyloric atresia, aplasia cutis congenita: histopathological delineation of an autosomal recessive disease. Am J Med Genet 1998; 78: 127-133.McCarthy MA, Clarke T, Powell FC. Epidermolysis bullosa and aplasia cutis. Int J Derm 1991; 30: 481-484.Puvabanditsin S, Garrow E, Daeun K

  6. Astroglial-Mediated Remodeling of the Interhemispheric Midline Is Required for the Formation of the Corpus Callosum

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    Ilan Gobius

    2016-10-01

    Full Text Available The corpus callosum is the major axon tract that connects and integrates neural activity between the two cerebral hemispheres. Although ∼1:4,000 children are born with developmental absence of the corpus callosum, the primary etiology of this condition remains unknown. Here, we demonstrate that midline crossing of callosal axons is dependent upon the prior remodeling and degradation of the intervening interhemispheric fissure. This remodeling event is initiated by astroglia on either side of the interhemispheric fissure, which intercalate with one another and degrade the intervening leptomeninges. Callosal axons then preferentially extend over these specialized astroglial cells to cross the midline. A key regulatory step in interhemispheric remodeling is the differentiation of these astroglia from radial glia, which is initiated by Fgf8 signaling to downstream Nfi transcription factors. Crucially, our findings from human neuroimaging studies reveal that developmental defects in interhemispheric remodeling are likely to be a primary etiology underlying human callosal agenesis.

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

    Science.gov (United States)

    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.

  8. [The gene mutation screening of a family with congenital fibrosis of the extraocular muscles associated with corpus callosum agenesis].

    Science.gov (United States)

    Zhang, Jun-tao; Zhou, Lian-hong; Zha, Yun-fei; Liu, Tian; Tian, Ming-xing; Yuan, Jing; Xing, Yi-qiao

    2013-07-01

    To identify TUBB3 gene mutations in a Chinese family with congenital fibrosis of the extraocular muscle associated with corpus callosum agenesis. We have found a family with CFEOM associated with corpus callosum agenesis, including 4 affected individuals in three generations of 11 familial members. 4 affected individuals were sequenced by direct TUBB3 sequencing, 4 unaffected individuals in the family and 100 cases of unrelated normal person as a control. This family is in line with Mendelian autosomal dominant inheritance. Clinical manifestations belongs to CFEOM3. All affected individuals were detected with TUBB3 c.1249G > A mutation, the mutation is in exon 4, resulting in wild-type gene encoding the Aspartic acid ( Asp or D ) replaced .by Asparagine (Asn or N ). Our study supports that TUBB3 gene mutation c.1249G > A (p. Asp417Asn), is the underlying molecular pathogenesis of this family with CFEOM3.

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

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    Yuan Jun

    2011-11-01

    Full Text Available Abstract 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.

  10. A reversible lesion of the corpus callosum splenium with adult influenza-associated encephalitis/encephalopathy: a case report

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    Kimura En

    2008-06-01

    Full Text Available ABstract Introduction Influenza virus-associated encephalitis/encephalopathy is a severe childhood illness with a poor prognosis. Adult case reports are rare and, to date, there have been no reports of adults with a mild subcortical encephalopathy with reversible lesions of the corpus callosum splenium. Case presentation A previously healthy 35-year-old man presented with acute progressive tetraplegia, transcortical motor aphasia and a mild decrease in his consciousness during his recovery after receiving oseltamivir phosphate treatment, and influenza type A antiviral medication. The initial magnetic resonance imaging study at day 1 showed symmetrical diffuse lesions in the white matter and a lesion on the central portion of the corpus callosum splenium. These findings had resolved on follow-up studies at day 8 and day 146. His neurological deficits mostly recovered within 12 hours following methylprednisolone pulse therapy. The levels of interleukin-6 and interleukin-10 in his blood and cerebrospinal fluid were initially elevated, but rapidly decreased to normal levels by day 8. Conclusion It is important for clinicians to recognize that even in adulthood, the subcortical encephalopathy observed during the therapeutic treatment for influenza type A infection can occur in conjunction with a reversible lesion of the corpus callosum, which may recover quickly. In addition, the cytokine storm in the blood system and the corticospinal cavity may play an important role in the etiology of the disease process.

  11. Cerebral Visual Impairment and Dysgenesis of Corpus Callosum in Multidisabled Children Aged 1 to 9 Years Old

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    Roxana CZIKER

    2009-12-01

    Full Text Available Aims: To emphasize the functional vision characteristics in visually impaired multiple disabled children (MDVI aged 2 to 9 years old related to brain damages on magnetic resonance imaging in different cortical and subcortical areas and in the corpus callosum region. Material and Method: 12 MDVI children with severe and mild neurological disorders were medically and neuropsychological assessed. The clinical - psychological, neurological and ophthalmological – and paraclinical methods – visual evoked potential (VEP and magnetic resonance imaging (MRI were carried out in order to outline the complete profile of each child. The assessment was completed by morphometric measurement of corpus callosum and brain. Results: 10 of infants with severe neurological disorders showed ocular disorders such as ocular motility and visual function abnormalities. Severe cognitive and psychomotor retardation were associated in visual disorders in MDVI children. Significant correlation between neurological disorders, neuropsychological [τ(12 = 0.783, p = 0.001] evaluation and visual acuity [τ(12 = 0.783, p = 0.001] were found in multiple disabled children. The significant difference of diameter [t(22 = -4.858, p = 0.000] and surface of corpus callosum [t(22 = -6.254, p = 0.000] in multiple disabled children compared with control group was found. Conclusion: The structured assessment of visually impaired children due to neurological disorders, as early as possible, is the remarkably key which reveals the functionality of child and outlines the appropriate developmental and educational rehabilitation.

  12. MR imaging of the corpus callosum in the patients of ischemic cerebrovascular disease

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    Umahara, Takahiko; Tanaka, Yuriko; Yamaguchi, Katsuhiko; Imamura, Toshiharu; Iwamoto, Toshihiko; Katsunuma, Hideyo (Tokyo Medical Coll. (Japan))

    1990-12-01

    We studied the abnormal MR morphology of the corpus callosum (CC) in 8 cases of progressive subcortical vascular encephalopathy (PSVE), 1 case of anterior cerebral artery (ACA) area hemorrhagic infarction, 5 cases of middle cerebral artery (MCA) area infarction, and 7 cases of posterior cerebral artery (PCA) area infarction (2 cases had bilateral PCA infarction). In addition, we studied the MR imaging of sagittal sulcal lesions of CC (SSLCC), and of inner callosal-subcallosal lesions (or inner callosal-subcallosal laminar hyperintensity; ICLH). PSVE usually showed diffuse attenuations of CC, and findings similar to a localized callosal infarction sometimes were observed. The ACA infarct case showed a rupture of the CC. The MCA infarct cases had focal attenuations (mainly at the body of the CC) caused by secondary degenerations. Only 1 of the 5 cases with unilateral PCA infarction showed a lesion in the splenium of the CC. These results are generally in accord with the results of our previous pathological study of the CC in ischemic cerebrovascular disease. Linear low signal intensity areas at the gneu found in 77% of our MRI cases, and we think these lesions compatible with SSLCC which we have studied previously. ICLH was found in the cases of PSVE, multi-infarct, and clinically normals. We therefore suggest that ICLH seems to have no disease specificity. (author).

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

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    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

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

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    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.

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

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

    2014-11-01

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

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

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    Michiko Miki

    2016-05-01

    Full Text Available 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.

  17. Diffusion tensor MR imaging evaluation of the corpus callosum of patients with multiple sclerosis

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    Rueda, Fernanda [Hospital Universitario Clementino Fraga Filho, Rio de Janeiro, RJ (Brazil). Servico de Radiodiagnostico; Hygino Junior, Luiz Celso; Vasconcelos, Claudia C. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Programa de Pos-Graduacao em Medicina (Radiologia); Domingues, Romeu Cortes [Clinica de Diagnostico Por Imagem e Multi-Imagem (CDPI), Rio de Janeiro, RJ (Brazil); Papais-Alvarenga, Regina M. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Gasparetto, Emerson L. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Faculdade de Medicina. Dept. de Radiologia]. E-mail: egasparetto@gmail.com

    2008-07-01

    Objective: To evaluate the fractional anisotropy (FA) values of the normal-appearing white matter of the corpus callosum (CC) in patients with relapsing-remitting multiple sclerosis (MS). Method: Fifty-seven patients with diagnosis of relapsing-remitting MS and 47 age- and gender-matched controls were studied. A conventional MR imaging protocol and a DTI sequence were performed. One neuro radiologist placed the regions of interest (ROIs) in the FA maps in five different portions of the normal-appearing CC (rostrum, genu, anterior and posterior portion of the body and splenium) in all cases. The statistical analysis was performed with the Mann-Whitney U test and p<0.05 was considered statistically significant. Results: The FA values were lower in the MS patients compared with the controls (p<0.05) in the following CC regions: rostrum (0.720 vs 0.819), anterior body (0.698 vs 0.752), posterior body (0.711 vs 0.759) and splenium (0.720 vs 0.880). Conclusion: In this series, there was a robust decrease in the FA in all regions of the normal-appearing CC, being significant in the rostrum, body and splenium. This finding suggests that there is a subtle and diffuse abnormality in the CC, which could be probably related to myelin content loss, axonal damage and gliosis. (author)

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

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    Daniel Reyes-Haro

    2015-01-01

    Full Text Available 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.

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

    Science.gov (United States)

    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

  20. Diffusion tensor imaging of corpus callosum integrity in multiple sclerosis: correlation with disease variables.

    Science.gov (United States)

    Sigal, Tal; Shmuel, Miron; Mark, Dolev; Gil, Harari; Anat, Achiron

    2012-01-01

    Corpus callosum (CC) is frequently involved in multiple sclerosis (MS). We aimed to investigate the relations between CC microstructure integrity as measured by diffusion tensor imaging (DTI) in relapsing-remitting MS patients with low neurological disability in comparison with age-matched healthy subjects and further to identify correlations between DTI-CC parameters and clinical variables of MS disease activity. CC volume was measured on 3.0T brain MRI by MS Analyze software. DTI metrics acquired along 31 independent directions were obtained and fractional anisotropy (FA), apparent diffusion coefficient (ADC), longitudinal (λ1) and transverse (λ 2, λ 3) diffusivities were measured in MS patients and healthy subjects. Disease activity was assessed by relapse rate and neurolgical disability by the Extended Disability Status Scale (EDSS). Thirty relapsing-remitting MS patients and 30 age- and sex-matched healthy subjects were studied. CC volume and DTI metrics differed significantly between MS patients and healthy subjects. In MS patients, all DTI parameters correlated with neurological disability. ADC, longitudinal and transverse diffusivity correlated with disease duration. ADC and the transverse diffusivity correlated with relapse rate. CC DTI parameters, especially ADC and transverse diffusivity correlated with disease variables especially with those associated with clinical activity. Copyright © 2010 by the American Society of Neuroimaging.

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

    Science.gov (United States)

    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

  2. White matter alterations in the corpus callosum of adolescents with first-admission schizophrenia.

    Science.gov (United States)

    Henze, Romy; Brunner, Romuald; Thiemann, Ulf; Parzer, Peter; Klein, Jan; Resch, Franz; Stieltjes, Bram

    2012-04-04

    Several diffusion tensor imaging (DTI) studies involving adults and adolescents with schizophrenia have examined fractional anisotropy (FA) in the corpus callosum (CC) with conflicting findings. This may be due to confounding factors such as the chronicity of the disorder, long-term medication with psychotropics or methodological differences. To provide a clearer picture of early alterations, we examined 13 adolescents with first-admission schizophrenia and 13 healthy controls using a region-of-interest approach based on probabilistic voxel classification. We quantified FA in four subdivisions of the CC and hypothesized that adolescents with schizophrenia display a reduced FA in the genu associated with 'hypofrontality' and a reduced FA in the body of the CC linked to the heteromodal association cortex. Fiber integrity measurements revealed significant FA decreases in the genu and body of the CC in adolescents with schizophrenia compared to healthy controls. These findings emphasize the central role of the CC in even the early stages of schizophrenia and lend weight to hypotheses about frontal alterations and the central role of the heteromodal association cortex in the aetiopathogenesis of the disorder. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

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

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    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.

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

    Science.gov (United States)

    Saenz, M; Fine, I

    2010-10-01

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

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

    Science.gov (United States)

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

    2014-05-27

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

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

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    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.

  7. Corpus callosum involvement: a useful clue for differentiating Fabry disease from multiple sclerosis

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    Cocozza, Sirio; Olivo, Gaia; Pontillo, Giuseppe; Ugga, Lorenzo; De Rosa, Dario; Imbriaco, Massimo; Brunetti, Arturo; Tedeschi, Enrico [University ' ' Federico II' ' , Department of Advanced Biomedical Sciences, Naples (Italy); Riccio, Eleonora; Migliaccio, Silvia; Pisani, Antonio [University ' ' Federico II' ' , Department of Public Health, Nephrology Unit, Naples (Italy); Russo, Camilla [University ' ' Federico II' ' , Department of Advanced Biomedical Sciences, Naples (Italy); Feriozzi, Sandro [Belcolle Hospital, Nephrology and Dialysis Department, Viterbo (Italy); Veroux, Massimiliano [University Hospital of Catania, Department of Medical and Surgical Sciences and Advanced Technologies, Catania (Italy); Battaglia, Yuri [St. Anna Hospital-University, Department of Specialized Medicine, Division of Nephrology and Dialysis, Ferrara (Italy); Concolino, Daniela [University Magna Graecia, Department of Pediatrics, Catanzaro (Italy); Pieruzzi, Federico [University of Milano-Bicocca, Nephrology Unit, Milan (Italy); Tuttolomondo, Antonino [University of Palermo, Internal Medicine, DiBiMIS, Palermo (Italy); Caronia, Aurelio [Triolo Zancia Care Home, Palermo (Italy); Russo, Cinzia Valeria; Lanzillo, Roberta; Brescia Morra, Vincenzo [University ' ' Federico II' ' , Department of Neurosciences and Reproductive and Odontostomatological Sciences, Naples (Italy)

    2017-06-15

    Multiple sclerosis (MS) has been proposed as a possible differential diagnosis for Fabry disease (FD). The aim of this work was to evaluate the involvement of corpus callosum (CC) on MR images and its possible role as a radiological sign to differentiate between FD and MS. In this multicentric study, we retrospectively evaluated the presence of white matter lesions (WMLs) on the FLAIR images of 104 patients with FD and 117 patients with MS. The incidence of CC-WML was assessed in the two groups and also in a subgroup of 37 FD patients showing neurological symptoms. WMLs were detected in 50 of 104 FD patients (48.1%) and in all MS patients. However, a lesion in the CC was detected in only 3 FD patients (2.9%) and in 106 MS patients (90.6%). In the FD subgroup with neurological symptoms, WMLs were present in 26 of 37 patients (70.3%), with two subjects (5.4%) showing a definite callosal lesion. FD patients have a very low incidence of CC involvement on conventional MR images compared to MS, independently from the clinical presentation and the overall degree of WM involvement. Evaluating the presence of CC lesions on brain MR scans can be used as a radiological sign for a differential diagnosis between MS and FD, rapidly addressing the physician toward a correct diagnosis and subsequent treatment options. (orig.)

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

    Directory of Open Access Journals (Sweden)

    Mara Fabri

    2013-01-01

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

  9. Focal transient lesion in the splenium of the corpus callosum in three non-epileptic patients

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    Rocha, Antonio Jose da; Pereira Pinto Gama, Hugo; Silva, Carlos Jorge da; Braga, Flavio Tulio [Santa Casa de Misericordia de Sao Paulo, Section of Radiology, Centro de Medicina Diagnostica Fleury, Sao Paulo (Brazil); Reis, Fabiano [State University of Campinas, Department of Radiology, Campinas (Brazil); Martins Maia, Antonio Carlos Junior [Federal University of Sao Paulo, Centro de Medicina Diagnostica Fleury, Department of Neurology, Escola Paulista de Medicina, Sao Paulo (Brazil); Cendes, Fernando [State University of Campinas, Department of Neurology, Campinas (Brazil)

    2006-10-15

    We analyzed the imaging features of transient focal lesions in the splenium of the corpus callosum (SCC) in non-epileptic patients receiving antiepileptic drugs (AEDs). We identified signal abnormalities in the SCC in three non-epileptic patients, all of them receiving AEDs. We examined two of these patients with multiplanar magnetic resonance (MR) imaging using 1.0-T equipment including fluid-attenuated inversion recovery (FLAIR), T2-weighted (TSE) and T1-weighted (SE) sequences before and after injection of contrast agent. The third patient was studied using 1.5-T equipment with the same sequences. Additionally, a T1 SE sequence with a magnetization transfer contrast pulse off resonance (T1 SE/MTC), diffusion-weighted imaging (EPI-DWI) and apparent diffusion coefficient (ADC) maps were obtained. We observed an identical pattern of imaging abnormalities in all patients characterized by round lesions, hyperintense on FLAIR and hypointense on T1 SE images, located in the central portion of the SCC. One lesion showed homogeneous gadolinium enhancement and perilesional vasogenic edema. This particular lesion showed restricted diffusion confirmed on the ADC map. This pattern was considered consistent with focal demyelination. Follow-up MR examinations showed complete disappearance or a clear reduction in lesion size. All patients had been treated with AEDs, but they did not show any clinical signs of toxicity, interhemispheric symptoms, or abnormal neurological findings (including seizures). (orig.)

  10. Transcriptome analysis of amoeboid and ramified microglia isolated from the corpus callosum of rat brain

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    Parakalan Rangarajan

    2012-06-01

    Full Text Available Abstract Background Microglia, the resident immune cells of the central nervous system (CNS, have two distinct phenotypes in the developing brain: amoeboid form, known to be amoeboid microglial cells (AMC and ramified form, known to be ramified microglial cells (RMC. The AMC are characterized by being proliferative, phagocytic and migratory whereas the RMC are quiescent and exhibit a slow turnover rate. The AMC transform into RMC with advancing age, and this transformation is indicative of the gradual shift in the microglial functions. Both AMC and RMC respond to CNS inflammation, and they become hypertrophic when activated by trauma, infection or neurodegenerative stimuli. The molecular mechanisms and functional significance of morphological transformation of microglia during normal development and in disease conditions is not clear. It is hypothesized that AMC and RMC are functionally regulated by a specific set of genes encoding various signaling molecules and transcription factors. Results To address this, we carried out cDNA microarray analysis using lectin-labeled AMC and RMC isolated from frozen tissue sections of the corpus callosum of 5-day and 4-week old rat brain respectively, by laser capture microdissection. The global gene expression profiles of both microglial phenotypes were compared and the differentially expressed genes in AMC and RMC were clustered based on their functional annotations. This genome wide comparative analysis identified genes that are specific to AMC and RMC. Conclusions The novel and specific molecules identified from the trancriptome explains the quiescent state functioning of microglia in its two distinct morphological states.

  11. The development of corpus callosum microstructure and associations with bimanual task performance in healthy adolescents.

    Science.gov (United States)

    Muetzel, Ryan L; Collins, Paul F; Mueller, Bryon A; M Schissel, Ann; Lim, Kelvin O; Luciana, Monica

    2008-02-15

    Cross-sectional and longitudinal volumetric studies suggest that the corpus callosum (CC) continues to mature structurally from infancy to adulthood. Diffusion tensor imaging (DTI) provides in vivo information about the directional organization of white matter microstructure and shows potential for elucidating even more subtle brain changes during adolescent development. We used DTI to examine CC microstructure in healthy right-handed adolescents (n=92, ages 9-24 years) and correlated the imaging data with motor task performance. The primary DTI variable was fractional anisotropy (FA), which reflects the degree of white matter's directional organization. Participants completed an alternating finger tapping test to assess interhemispheric transfer and motor speed. Task performance was significantly correlated with age. Analyses of variance indicated that 9- to 11-year-olds generally performed worse than each of the older groups. Males outperformed females. Significant positive correlations between age and FA were observed in the splenium of the CC, which interconnects posterior cortical regions. Analyses of variance indicated that individuals older than 18 years had significantly higher FA than 9- to 11-year-olds. FA levels in the genu and splenium correlated significantly with task performance. Regression analyses indicated that bimanual coordination was significantly predicted by age, gender, and splenium FA. Decreases in alternating finger tapping time and increases in FA likely reflect increased myelination in the CC and more efficient neuronal signal transmission. These findings expand upon existing neuroimaging reports of CC development by showing associations between bimanual coordination and white matter microstructural organization in an adolescent sample.

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

    Science.gov (United States)

    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).

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

    Science.gov (United States)

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

    2015-11-07

    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. © 2015 The Author(s).

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

    Science.gov (United States)

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

    2011-03-01

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

  15. Diffusion tensor imaging of early changes in corpus callosum after acute cerebral hemisphere lesions in newborns

    Energy Technology Data Exchange (ETDEWEB)

    Righini, Andrea; Doneda, Chiara; Parazzini, Cecilia; Arrigoni, Filippo; Triulzi, Fabio [Children' s Hospital V. Buzzi, ICP, Radiology and Neuroradiology Department, Milan (Italy); Matta, Ursula [University of Milan, Radiology Institute, Milan (Italy)

    2010-11-15

    The main purpose was to investigate any early diffusion tensor imaging (DTI) changes in corpus callosum (CC) associated with acute cerebral hemisphere lesions in term newborns. We retrospectively analysed 19 cases of term newborns acutely affected by focal or multi-focal lesions: hypoxic-ischemic encephalopathy, hypoglycaemic encephalopathy, focal ischemic stroke and deep medullary vein associated lesions. DTI was acquired at 1.5 Tesla with dedicated neonatal coil. DTI metrics (apparent diffusion coefficient (ADC), fractional anisotropy (FA), axial {lambda} {sub parallel} and radial {lambda} diffusivity) were measured in the hemisphere lesions and in the CC. The control group included seven normal newborns. The following significant differences were found between patients and normal controls in the CC: mean ADC was lower in patients (0.88 SD 0.23 versus 1.18 SD 0.07 {mu}m{sup 2}/s) and so was mean FA (0.50 SD 0.1 versus 0.67 SD 0.05) and mean {lambda} {sub parallel} value (1.61 SD 0.52 versus 2.36 SD 0.14 {mu}m{sup 2}/s). In CC the percentage of ADC always diminished independently of lesion age (with one exception), whereas in hemisphere lesions, it was negative in earlier lesions, but exceeded normal values in the older lesions. CC may undergo early DTI changes in newborns with acute focal or multi-focal hemisphere lesions of different aetiology. Although a direct insult to CC cannot be totally ruled out, DTI changes in CC (in particular {lambda} {sub parallel}) may also be compatible with very early Wallerian degeneration or pre-Wallerian degeneration. (orig.)

  16. Early anisotropy changes in the corpus callosum of patients with optic neuritis

    Energy Technology Data Exchange (ETDEWEB)

    Bester, M.; Ding, X.Q.; Holst, B.; Fiehler, J. [University Medical Center Hamburg-Eppendorf, Department of Neuroradiology, Hamburg (Germany); Heesen, C.; Schippling, S.; Martin, R. [University Medical Center Hamburg-Eppendorf, Department of Neuroradiology, Hamburg (Germany); University Medical Center Hamburg-Eppendorf, Institute for Neuroimmunology and Clinical MS Research, Hamburg (Germany)

    2008-07-15

    Optic neuritis (ON) and any other early manifestation of multiple sclerosis (MS) are referred to as clinically isolated syndrome (CIS) as long as MS is suspected. In this prospective study we aimed to determine whether diffusion tensor imaging (DTI) could quantify structural changes in patients with early MS. A total of 24 patients and 15 control subjects were prospectively followed by clinical examinations and MRI. the main inclusion criterion was presentation with ON. Patients underwent serial MRI scans: MRI1 (baseline, n=24), MRI2 (mean 6.6 months, n=24), MRI3 (mean 13.0 months, n=14), MRI4 (mean 39.4 months, n=5). Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) maps were derived from DTI. Four regions of interest (ROIs) were defined in normal-appearing white matter (NAWM). In the temporal course FA decreased in the genu of the callosal body (GCC) from MRI1 to MRI4 (P=0.005) and in the splenium of the callosal body (SCC) (P=0.006). Patients already had lower FA values in the SCC (P<0.01) on MRI1 compared with the controls. Patients had lower FA values in the GCC (P<0.01) starting from MRI2. Patients with definite MS on follow-up (n=9) showed a correlation between FA in the SCC and time (r=-0.40, P=0.004), whereas patients without progression did not. Our findings suggest that the corpus callosum is an early site for development of anisotropy changes in MS patients with ON. There seems to be a primary FA decrease in all patients with ON that only deteriorates in the group developing definite MS. (orig.)

  17. Progesterone Enhanced Remyelination in the Mouse Corpus Callosum After Cuprizone Induced Demyelination

    Directory of Open Access Journals (Sweden)

    Iraj Ragerdi Kashani

    2015-11-01

    Full Text Available Background: Progesterone as a sex steroid hormone is thought to affect and prevent demyelination, but its role in promoting myelin repair is far less investigated. In this study, remyelinating potential of progesterone in corpus callosum was evaluated on an experimental model of MS. Methods: In this experimental study, adult male C57BL/6 mice were fed with 0.2% (w/w cuprizone in ground breeder chow ad libitum for 6 weeks. At day zero, after cuprizone removal, mice were divided randomly into two groups: (a placebo group, which received saline pellet implant, (b progesterone group, which received progesterone pellet implant. Some mice of the same age were fed with their normal diet to serve as the healthy control group. Two weeks after progesterone administration, Myelin content was assessed by Luxol-fast blue staining. The myelin basic protein (MBP and proteolipid protein (PLP expression were assessed using Western blot analysis and the changes in the number of oligodendrocytes and oligodendroglial progenitor cells were assessed by immunohistochemistry (IHC and flow cytometry. Results: Luxol-fast blue staining revealed enhanced remyelination in the progesterone group when compared with the placebo group. Densitometry measurements of immunoblots demonstrated that MBP and PLP proteins contents were significantly increased in the progesterone group compared with the placebo group. Flow cytometry and IHC analysis showed increases in Olig2 and O4 cells in the progesterone group compared with the placebo group. Conclusion: Overall, our results indicate that progesterone treatment can stimulate myelin production and that it may provide a feasible and practical way for remyelination in diseases such as multiple sclerosis.

  18. Histological correlation of diffusional kurtosis and white matter modeling metrics in cuprizone-induced corpus callosum demyelination.

    Science.gov (United States)

    Falangola, Maria F; Guilfoyle, David N; Tabesh, Ali; Hui, Edward S; Nie, Xingju; Jensen, Jens H; Gerum, Scott V; Hu, Caixia; LaFrancois, John; Collins, Heather R; Helpern, Joseph A

    2014-08-01

    The cuprizone mouse model is well established for studying the processes of both demyelination and remyelination in the corpus callosum, and it has been utilized together with diffusion tensor imaging (DTI) to investigate myelin and axonal pathology. Although some underlying morphological mechanisms contributing to the changes in diffusion tensor (DT) metrics have been identified, the understanding of specific associations between histology and diffusion measures remains limited. Diffusional kurtosis imaging (DKI) is an extension of DTI that provides metrics of diffusional non-Gaussianity, for which an associated white matter modeling (WMM) method has been developed. The main goal of the present study was to quantitatively assess the relationships between diffusion measures and histological measures in the mouse model of cuprizone-induced corpus callosum demyelination. The diffusional kurtosis (DK) and WMM metrics were found to provide additional information that enhances the sensitivity to detect the morphological heterogeneity in the chronic phase of the disease process in the rostral segment of the corpus callosum. Specifically, in the rostral segment, axonal water fraction (d = 2.6; p < 0.0001), radial kurtosis (d = 2.0; p = 0.001) and mean kurtosis (d = 1.5; p = 0.005) showed the most sensitivity between groups with respect to yielding statistically significant p values and high Cohen's d values. These results demonstrate the ability of DK and WMM metrics to detect white mater changes and inflammatory processes associated with cuprizone-induced demyelination. They also validate, in part, the application of these new WMM metrics for studying neurological diseases, as well as helping to elucidate their biophysical meaning.

  19. MRI in callosal apraxia and agraphia due to a traumatic lesion in the posterior trunk of the corpus callosum

    Energy Technology Data Exchange (ETDEWEB)

    Yasumura, Shuichi; Ito, Naoki; Terunuma, Hiroshi; Matsuzaki, Takayuki; Iwabuchi, Reiko

    1987-08-01

    We discussed functional topography of the corpus callosum in a case with ideo-motor apraxia and agraphia of the left hand due to a traumatic callosal hematoma confirmed by MRI. The patient was a 35-year-old right-handed woman with head injury in a traffic accident. On admission she was semi-comatose with left oculomotor palsy and her left upper limb showed a decorticate rigidity by noxious stimuli, however, she became alert within 14 days. X-ray CT showed an abnormal high density area in the posterior part of the trunk of the corpus callosum on admission. MRI (inversion recovery technique) on the 60th hospital day showed a low intensity area extending for about 2 cm posteriorly from the center of the trunk. Sequential neuropsychological examinations for the callosal disconnection syndrome were performed. The patient showed ideo-motor apraxia and agraphia in her left hand only. Her response to verbal commands were all parapraxic except for correct use of a comb and a tooth brush. Her writings with her left hand were those of scrawls due to apraxia. These apraxia and agraphia of the left hand were transient and recovered completely within 80 days of onset. Transient impairement of bimanual coordination movement was also observed. Ataxie optique, callosal pseudoneglect, left hand tactile anomia, difficulty of somesthetic transfer or diagonistic dyspraxia was not observed. Based on the neuropsychological and the MRI findings we suggest that the lesion in the posterior part of the trunk of the corpus callosum is important for causing ideo-motor apraxia and agraphia of the left hand.

  20. Transient Splenial Lesion of Corpus Callosum Associated with Antiepileptic Drug: Conventional and Diffusion-weighted Magnetic Resonance Images

    Energy Technology Data Exchange (ETDEWEB)

    Hakyemez, B.; Erdogan, C.; Yildirim, N.; Gokalp, G.; Parlak, M. [Uludag Univ. Medical School, Bursa (Turkey). Dept. of Radiology

    2005-11-01

    Transient focal lesions of splenium of corpus callosum can be seen as a component of many central nervous system diseases, including antiepileptic drug toxicity. The conventional magnetic resonance (MR) findings of the disease are characteristic and include ovoid lesions with high signal intensity at T2-weighted MRI. Limited information exists about the diffusion-weighted MRI characteristics of these lesions vanishing completely after a period of time. We examined the conventional, FLAIR, and diffusion-weighted MR images of a patient complaining of depressive mood and anxiety disorder after 1 year receiving antiepileptic medication.

  1. Human amniotic epithelial cells express specific markers of nerve cells and migrate along the nerve fibers in the corpus callosum

    Institute of Scientific and Technical Information of China (English)

    Zhiyuan Wu; Guozhen Hui; Yi Lu; Tianjin Liu; Qin Huang; Lihe Guo

    2012-01-01

    Human amniotic epithelial cells were isolated from a piece of fresh amnion. Using immunocytochemical methods, we investigated the expression of neuronal phenotypes (microtubule-associated protein-2, glial fibrillary acidic protein and nestin) in human amniotic epithelial cells. The conditioned medium of human amniotic epithelial cells promoted the growth and proliferation of rat glial cells cultured in vitro, and this effect was dose-dependent. Human amniotic epithelial cells were further transplanted into the corpus striatum of healthy adult rats and the grafted cells could integrate with the host and migrate 1-2 mm along the nerve fibers in corpus callosum. Our experimental findings indicate that human amniotic epithelial cells may be a new kind of seed cells for use in neurograft.

  2. 胼胝体梗死的临床与影像学分析%Clinical and imaging analysis of corpus callosum infarction

    Institute of Scientific and Technical Information of China (English)

    李新辉; 王玉洁; 白璇; 辛岳

    2011-01-01

    Objective To investigate the clinical and imaging characteristics in patients with corpus callosum infarction.Methods The clinical data of 416 patients meetingthe diagnosis of cerebral infarction Were collected,in which,8 patients Were confirmed as corpus callosum infarction by MRI.Results Corpus callosum infarction accounted for 1.9% of all patients with cerebral infarction.CT scan did not show the corpus callosum infaretiom in 7 patients.The nonenhanced MRI revealed the lesions.The enhanced MRI revealed the lesion in another patient.The infarction foci were not only involved in the corpus callosum(knee,body or splenium),but also cornplicated with frontal lobe,occipital lobe and thalamus infractions.The clinical manifesta tions of the corpus callosum infarction were different due to the specific lesion sites.The simple infarction in the body of the corpus callosum mainly presented as contralateral paraparesis.atria,and left limb apra.xia;the infarction in the knee of the corpus callosum mainly presented as lower limb paralysis or contralateral paraparesis;the infarction in the splenium of the corpus callosum presented as limb paralysis and dizziness;the lacunar infarct in the corpus callosum had no obvious clinical manifestations.The patients who complicated with frontal lobe and thalamus infarction had behavioral and psychological syrnptonm,including mental retardation,language abnormalities.and incontinence.Conelusions Corpus callosum infarction is not common.MRI is the basis of diagaosis.The clinical manifestation is lack of specificity.and it is agsociated with the location of corpus callosum infarction and whether it comolicates with the infarction on other part.%目的 探讨胼胝体梗死患者的临床和影像学特点.方法 收集符合脑梗死诊断的416例患者的临床资料,其中8例经过MRI证实为胼胝体梗死.结果 胼胝体梗死占全部脑梗死患者的1.9%.7例CT扫描未显示胼胝体梗死,经非增强MRI检查显示病灶,另1

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  6. Microstructural white matter changes in the corpus callosum of young people with Bipolar Disorder: a diffusion tensor imaging study.

    Directory of Open Access Journals (Sweden)

    Jim Lagopoulos

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

  7. Cerebral metabolic and structural alterations in hereditary spastic paraplegia with thin corpus callosum assessed by MRS and DTI

    Energy Technology Data Exchange (ETDEWEB)

    Dreha-Kulaczewski, Steffi [Georg August University, Department of Pediatrics and Pediatric Neurology, Faculty of Medicine, Goettingen (Germany); Georg August University, MR Research in Neurology and Psychiatry, Goettingen (Germany); Dechent, Peter; Helms, Gunther [Georg August University, MR Research in Neurology and Psychiatry, Goettingen (Germany); Frahm, Jens [Biomedizinische NMR Forschungs GmbH, Max-Planck-Institut fuer Biophysikalische Chemie, Goettingen (Germany); Gaertner, Jutta; Brockmann, Knut [Georg August University, Department of Pediatrics and Pediatric Neurology, Faculty of Medicine, Goettingen (Germany)

    2006-12-15

    Hereditary spastic paraplegia with thin corpus callosum (HSP-TCC) is a complicated form of autosomal-recessive hereditary spastic paraplegia. Characteristic clinical features comprise progressive spastic gait, cognitive impairment, and ataxia. Diagnostic MRI findings include thinning of the corpus callosum and non-progressive white matter (WM) alterations. To study the extent of axonal involvement, we performed localized proton magnetic resonance spectroscopy (MRS) of the cerebral WM and cortical grey matter (GM) in a patient with HSP-TCC at 20 and 25 years of age. The second investigation included diffusion tensor imaging (DTI). While MRS of the GM was normal, affected WM was characterized by major metabolic alterations such as reduced concentrations of N-acetylaspartate and N-acetylaspartyl-glutamate, creatine and phosphocreatine, and choline-containing compounds as well as elevated levels of myo-inositol. These abnormalities showed progression over a period of 5 years. DTI revealed increased mean diffusivity as well as reduced fractional anisotropy in periventricular WM. The metabolic and structural findings are consistent with progressive neuroaxonal loss in the WM accompanied by astrocytic proliferation - histopathological changes known to occur in HSP-TCC. Our results are in agreement with the hypothesis that the primary pathological process in HSP-TCC affects the axon, possibly due to impaired axonal trafficking. (orig.)

  8. Myelin in the frontal region of corpus callosum in old rats%老年大鼠胼胝体额区有髓神经纤维与髓鞘改变的研究

    Institute of Scientific and Technical Information of China (English)

    徐瑲; 兰欢; 卢伟; 唐勇

    2011-01-01

    目的:探讨老年大鼠胼胝体额区有髓神经纤维、髓鞘的结构变化和髓鞘碱性蛋白(Myelin basic protein,MBP)的表达变化,以及二者间的关系.方法:运用透射电子显微镜和新的体视学方法分别对年轻组和老年组雌性Long-Evans大鼠胼胝体额区有髓神经纤维和髓鞘进行定量研究,运用Western blot对年轻组和老年组大鼠胼胝体额区MBP表达进行定量研究.结果:与年轻组相比,老年组胼胝体额区体积存在显著性降低,有髓神经纤维总体积显著性下降,21.5 kD MBP表达量显著性降低.21.5 kD MBP的表达降低与有髓神经纤维总体积、髓鞘总体积的降低之间呈正相关.结论:胼胝体存在显著性老年萎缩,胼胝体额区有髓神经纤维和MBP的老年改变可能与老年大脑额叶功能下降有关.%Objective : To explore the age-related changes of the mvelinated fihers ,myelin sheath and the expression of myelin basic protein in the frontal region of the corpus callosum in old rats , and their relationship. Methods : The myelinated fibers and sheathes in the frontal region of corpus callosum of young and old-aged female Long-Evans rats were quantitatively studied using electron microscope and unhiased stereological techniques.Myelin basic proteins in the frontal region of corpus callosum of young and old-aged female rats were quantitatively studied using Western hlot. Results : When compared with young female rats, the total volume of the frontal region of the corpus callosum and the total volume of the myelinated fibers in the frontal region of old corpus callosum were significantly degraded. The expression of 21.5 kD MBP was significantly decreased in old rats. The reduction of the expression of 21.5 kD MBP,the reduction of the total volume of the myelinated fihers and the total volume of the myelin sheathes were positively correlated. Conclusion : There is age-related atrophy of the frontal region of corpus callosum. The age

  9. Estimation and Perturbation of the Mid-Sagittal Plane and its Effects on Corpus Callosum Morphometry

    DEFF Research Database (Denmark)

    Skoglund, Karl; Stegmann, Mikkel Bille; Ryberg, Charlotte

    2005-01-01

    callosum (CC), the white-matter nervous tissue bridging the left and right cerebral hemisphere. A multitude of papers (e.g. [2]) report on measurements performed on the two-dimensional cross-section of the CC defined by the mid-sagittal plane (MSP) which separates the left hemisphere from the right...

  10. Evaluating g-ratio weighted changes in the corpus callosum as a function of age and sex.

    Science.gov (United States)

    Berman, Shai; West, Kathryn L; Does, Mark D; Yeatman, Jason D; Mezer, Aviv A

    2017-06-30

    Recent years have seen a growing interest in relating MRI measurements to the structural-biophysical properties of white matter fibers. The fiber g-ratio, defined as the ratio between the inner and outer radii of the axon myelin sheath, is an important structural property of white matter, affecting signal conduction. Recently proposed modeling methods that use a combination of quantitative-MRI signals, enable a measurement of the fiber g-ratio in vivo. Here we use an MRI-based g-ratio estimation to observe the variance of the g-ratio within the corpus callosum, and evaluate sex and age related differences. To estimate the g-ratio we used a model (Stikov et al., 2011; Duval et al., 2017) based on two different WM microstructure parameters: the relative amounts of myelin (myelin volume fraction, MVF) and fibers (fiber volume fraction, FVF) in a voxel. We derived the FVF from the fractional anisotropy (FA), and estimated the MVF by using the lipid and macromolecular tissue volume (MTV), calculated from the proton density (Mezer et al., 2013). In comparison to other methods of estimating the MVF, MTV represents a stable parameter with a straightforward route of acquisition. To establish our model, we first compared histological MVF measurements (West et al., 2016) with the MRI derived MTV. We then implemented our model on a large database of 92 subjects (44 males), aged 7 to 81, in order to evaluate age and sex related changes within the corpus callosum. Our results show that the MTV provides a good estimation of MVF for calculating g-ratio, and produced values from the corpus callosum that correspond to those found in animals ex vivo and are close to the theoretical optimum, as well as to published in vivo data. Our results demonstrate that the MTV derived g-ratio provides a simple and reliable in vivo g-ratio-weighted (GR*) measurement in humans. In agreement with theoretical predictions, and unlike other tissue parameters measured with MRI, the g

  11. Novel missense mutation in the L1 gene in a child with corpus callosum agenesis, retardation, adducted thumbs, spastic paraparesis, and hydrocephalus

    NARCIS (Netherlands)

    Sztriha, L; Frossard, P; Hofstra, RMW; Verlind, E; Nork, M

    2000-01-01

    Corpus callosum agenesis, retardation, adducted thumbs, spastic paraparesis, and hydrocephalus (CRASH syndrome) is an X-linked recessive disorder caused by mutations in the neuronal cell adhesion molecule L1 (L1CAM) gene. L1 plays a key role in axon outgrowth and pathfinding during the development o

  12. Lipoma del cuerpo calloso con crisis convulsiva que ocasiona broncoaspiración alimentaria mortal Lipoma of the corpus callosum with seizure which causes fatal alimentary aspiration

    Directory of Open Access Journals (Sweden)

    J. Lucena

    2004-07-01

    Full Text Available Los lipomas del cuerpo calloso representan hasta el 5% de las malformaciones, tumorales o no, del cuerpo calloso. Actualmente son considerados malformaciones congénitas en lugar de verdaderas neoplasias. La mayoría son sintomáticos, pero algunos se asocian a síntomas neurológicos inespecíficos como retraso psicomotor, cefalea, epilepsia y parálisis cerebral. Se expone el caso de un varón de 42 años que fallece por broncoaspiración alimentaria secundaria a crisis convulsiva. El estudio neuropatológico puso de manifiesto dos lipomas situados en la rodilla del cuerpo calloso. Se destaca la necesidad de realizar tratamiento antiepiléptico en los lipomas del cuerpo calloso que se manifiestan clínicamente en forma de crisis comiciales.Lipomas of the corpus callosum make up approximately 5% of the tumours of the corpus callosum. Nowadays, they are considered congenital malformations rather than true neoplasms. They are usually asymptomatic; however they are sometimes associated with unspecific neurological symptoms such as psychomotor retardation, headache, epilepsy and cerebral palsy. A case is presented of a 42-year-old man who died due to alimentary aspiration following a seizure. Neuropathological study showed two lipomas located in the splenium of the corpus callosum. Also, we emphasise the importance of the anti-epileptic treatment in the corpus callosum lipomas which are associated with epilepsy.

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

    Science.gov (United States)

    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.

  14. A transient lesion in splenium of the corpus callosum in a patient with childhood-onset anorexia nervosa.

    Science.gov (United States)

    Nishimura, Katsuhiko; Takei, Nori; Suzuki, Katsuaki; Kawai, Masayoshi; Sekine, Yoshimoto; Isoda, Haruo; Mori, Norio

    2006-09-01

    Although a transient lesion in the splenium of the corpus callosum (SCC) has been reported predominantly regarding patients with epilepsia, it is of rare occurrence, and its underlying biological basis remains unknown. This is a report of an SCC lesion in a patient with anorexia nervosa (AN). The patient was a 15-year-old girl with childhood-onset (11 years) and a protracted course of AN. On admission, the patient showed no apparent neurological abnormalities. Magnetic resonance imaging (MRI) scans revealed a circumscribed lesion in the SCC. We treated her with nutritional rehabilitation supplemented with B vitamins. One month later, the lesion completely disappeared, but her weight was not restored. Treatment with B-vitamin supplementation may be beneficial for the treatment of patients with AN, in cases in which the disorder develops at an early age before brain maturation (i.e., childhood-onset cases), along with an enduring course of malnutrition. Copyright (c) 2006 by Wiley Periodicals, Inc.

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

    Science.gov (United States)

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

    2016-01-19

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

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

    Institute of Scientific and Technical Information of China (English)

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

    2013-01-01

    Length and thickness of 152 corpus cal osa were measured in neonates within 24 hours of birth. Using ultrasonic diagnostic equipment with a neonatal brain-specific probe, corpus cal osum 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 cal osum length as wel as thickness of the genu and splenium increased with gesta-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 cal osum de-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 cal osum size during the neonatal period. A second set of measurements were taken from 40 premature infants whose ges-tational age was 34 weeks or less. Corpus cal osum 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 cal osum length and genu and splenium thicknesses were less in those with abnormalities, indicating that corpus cal osum growth in premature infants is associated with neurobehavioral de-velopment during the early extrauterine stage.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Lall Meena

    2011-09-01

    Full Text Available Abstract Background Partial Trisomy 11q syndrome (or Duplication 11q has defined clinical features and is documented as a rare syndrome by National Organization of Rare Disorders (NORD. Deletion 1q44 (or Monosomy 1q44 is a well-defined syndrome, but there is controversy about the genes lying in 1q44 region, responsible for agenesis of the corpus callosum. We report a female child with the rare Partial Trisomy 11q syndrome and Deletion 1q44 syndrome. The genomic imbalance in the proband was used for molecular characterization of the critical genes in 1q44 region for agenesis of corpus callosum. Some genes in 11q14q25 may be responsible for laryngomalacia. Results We report a female child with dysmorphic features, microcephaly, growth retardation, seizures, acyanotic heart disease, and hand and foot deformities. She had agenesis of corpus callosum, laryngomalacia, anterior ectopic anus, esophageal reflux and respiratory distress. Chromosome analysis revealed a derivative chromosome 1. Her karyotype was 46,XX,der(1t(1;11(q44;q14pat. The mother had a normal karyotype and the karyotype of the father was 46,XY,t(1;11(q44;q14. SNP array analysis showed that the proband had a 54 Mb duplication of 11q14q25 and a 0.9 Mb deletion of the submicroscopic subtelomeric 1q44 region. Fluorescence Insitu Hybridisation confirmed the duplication of 11qter and deletion of 1qter. Conclusion Laryngomalacia or obstruction of the upper airway is the outcome of increased dosage of some genes due to Partial Trisomy 11q Syndrome. In association with other phenotypic features, agenesis of corpus callosum appears to be a landmark phenotype for Deletion 1q44 syndrome, the critical genes lying proximal to SMYD3 in 1q44 region.

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

    Science.gov (United States)

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

    2008-01-01

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

  2. Instrument specific use-dependent plasticity shapes the anatomical properties of the corpus callosum: A comparison between musicians and non-musicians

    Directory of Open Access Journals (Sweden)

    Henning eVollmann

    2014-07-01

    Full Text Available Long-term musical expertise has been shown to be associated with a number of functional and structural brain changes, making it an attractive model for investigating use-dependent plasticity in humans. Physiological interhemispheric inhibition (IHI as examined by transcranial magnetic stimulation has been shown to be correlated with anatomical properties of the corpus callosum as indexed by fractional anisotropy (FA. However, whether or not IHI or the relationship between IHI and FA in the corpus callosum can be modified by different musical training regimes remains largely unknown. We investigated this question in musicians with different requirements for bimanual finger movements (piano and string players and non-expert controls. IHI values were generally higher in musicians, but differed significantly from non-musicians only in string players. IHI was correlated with FA in the posterior midbody of the corpus callosum across all participants. Interestingly, subsequent analyses revealed that this relationship may indeed be modulated by different musical training regimes. Crucially, while string players had greater IHI than non-musicians and showed a positive structure-function relationship, the amount of IHI in pianists was comparable to that of non-musicians and there was no significant structure-function relationship. Our findings indicate instrument specific use-dependent plasticity in both functional (IHI and structural (FA connectivity of motor related brain regions in musicians.

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

    Science.gov (United States)

    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. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

  4. Degeneration of corpus callosum and recovery of motor function after stroke: a multimodal magnetic resonance imaging study.

    Science.gov (United States)

    Wang, Ling E; Tittgemeyer, Marc; Imperati, Davide; Diekhoff, Svenja; Ameli, Mitra; Fink, Gereon R; Grefkes, Christian

    2012-12-01

    Animal models of stroke demonstrated that white matter ischemia may cause both axonal damage and myelin degradation distant from the core lesion, thereby impacting on behavior and functional outcome after stroke. We here used parameters derived from diffusion magnetic resonance imaging (MRI) to investigate the effect of focal white matter ischemia on functional reorganization within the motor system. Patients (n = 18) suffering from hand motor deficits in the subacute or chronic stage after subcortical stroke and healthy controls (n = 12) were scanned with both diffusion MRI and functional MRI while performing a motor task with the left or right hand. A laterality index was employed on activated voxels to assess functional reorganization across hemispheres. Regression analyses revealed that diffusion MRI parameters of both the ipsilesional corticospinal tract (CST) and corpus callosum (CC) predicted increased activation of the unaffected hemisphere during movements of the stroke-affected hand. Changes in diffusion MRI parameters possibly reflecting axonal damage and/or destruction of myelin sheath correlated with a stronger bilateral recruitment of motor areas and poorer motor performance. Probabilistic fiber tracking analyses revealed that the region in the CC correlating with the fMRI laterality index and motor deficits connected to sensorimotor cortex, supplementary motor area, ventral premotor cortex, superior parietal lobule, and temporoparietal junction. The results suggest that degeneration of transcallosal fibers connecting higher order sensorimotor regions constitute a relevant factor influencing cortical reorganization and motor outcome after subcortical stroke. Copyright © 2011 Wiley Periodicals, Inc.

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

    Science.gov (United States)

    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.

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

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    Sabine eHofer

    2015-05-01

    Full Text Available Using diffusion-tensor MRI and fiber tractography the topographic organization of the corpus callosum (CC has been described to comprise 5 segments with fibers projecting into prefrontal (I, premotor and supplementary motor (II, primary motor (III, and primary sensory areas (IV, as well as into parietal, temporal, and occipital cortical areas (V. In order to more rapidly characterize the underlying anatomy of these segments, this study used a novel single-shot T1 mapping method to quantitatively determine T1 relaxation times in the human CC. A region-of-interest analysis revealed a tendency for the lowest T1 relaxation times in the genu and the highest T1 relaxation times in the somatomotor region of the CC. This observation separates regions dominated by myelinated fibers with large diameters (somatomotor area from densely packed smaller axonal bundles (genu with less myelin. The results indicate that characteristic T1 relaxation times in callosal profiles provide an additional means to monitor differences in fiber anatomy, fiber density, and gray matter in respective neocortical areas. In conclusion, rapid T1 mapping allows for a characterization of the axonal architecture in an individual CC in less than 10 s. The approach emerges as a valuable means for studying neocortical brain anatomy with possible implications for the diagnosis of neurodegenerative processes.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2015-01-01

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

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

    Science.gov (United States)

    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

  10. Structural organization of the corpus callosum predicts the extent and impact of cortical activity in the nondominant hemisphere.

    Science.gov (United States)

    Putnam, Mary Colvin; Wig, Gagan S; Grafton, Scott T; Kelley, William M; Gazzaniga, Michael S

    2008-03-12

    Diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI) were combined to examine the relationship between callosal organization and cortical activity across hemispheres. Healthy young adults performed an incidental verbal encoding task (semantic judgments on words) while undergoing fMRI. Consistent with previous studies, the verbal encoding task was associated with left-lateralized activity in the inferior prefrontal cortex (LIPFC). When subjects were divided into two groups based on fractional anisotropy (FA) values in the anterior corpus callosum (DTI), individuals with low anterior callosal FA were found to exhibit greater activity in a homologous region within the right inferior prefrontal cortex (RIPFC) relative to those with high anterior callosal FA. Interestingly, whereas the magnitude of RIPFC activity did not negatively impact subsequent verbal memory performance for individuals with low anterior callosal FA, greater RIPFC activity during verbal encoding was associated with poorer subsequent memory performance for individuals with high anterior callosal FA. Together, these findings provide novel evidence that individual differences in callosal organization are related to the extent of nondominant cortical activity during performance during a lateralized task, and further, that this relationship has consequences on behavior.

  11. Reduced corpus-callosum volume in posttraumatic stress disorder highlights the importance of interhemispheric connectivity for associative memory.

    Science.gov (United States)

    Saar-Ashkenazy, Rotem; Cohen, Jonathan E; Guez, Jonathan; Gasho, Chris; Shelef, Ilan; Friedman, Alon; Shalev, Hadar

    2014-02-01

    Memory deficits are a common complaint of patients with posttraumatic stress disorder (PTSD). Despite vivid trauma-related memory, previous studies report memory impairment for nontrauma-related stimuli when compared to controls, specifically in associative memory (Guez et al., 2011). Healthy individuals show hemispheric memory asymmetry with left-prefrontal lateralization of encoding and right-prefrontal lateralization of episodic retrieval, suggesting a role for interhemispheric communication in memory-related tasks (Gazzaniga, ; Ringo, Doty, Demeter, & Simard, ). Because brain magnetic resonance imaging (bMRI) studies in PTSD patients report volume changes in various regions, including white matter and corpus callosum (CC), we aimed to test the relationship between memory deficits and CC volume in PTSD patients. We probed for specific alterations in associative memory in PTSD and measured the volume of subportions within the CC employing bMRI. Our main finding was a reduction in CC white-matter volume in PTSD patients, as compared to controls, t(35) = -2.7, p = .010, that was correlated with lower associative performance (r = .76, p = .003). We propose that CC volume reduction is a substrate for the associative memory deficits found in PTSD. Copyright © 2014 International Society for Traumatic Stress Studies.

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

    Science.gov (United States)

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

    2012-10-30

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

  13. MR imaging findings of the corpus callosum region in the differentiation between multiple sclerosis and neuromyelitis optica

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    Chen, Zhiye, E-mail: yyqf@hotmail.com [Department of Radiology, PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China); Feng, Feng, E-mail: cjr.fengfeng@vip.163.com [Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Shuaifuyuan, Wangfujing, Beijing 100730 (China); Yang, Yang, E-mail: whitean0584@sina.com.cn [Department of Neurology, PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China); Li, Jinfeng, E-mail: lijf_301@163.com [Department of Radiology, PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China); Ma, Lin, E-mail: cjr.malin@vip.163.com [Department of Radiology, PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China)

    2012-11-15

    Purpose: To evaluate MR imaging findings in corpus callosum region for the discrimination between opticospinal multiple sclerosis (OSMS) and neuromyelitis optica (NMO). Materials and methods: Forty-two definite OSMS with seronegative NMO-IgG and 23 NMO with seropositive NMO-IgG, and 27 age-matched normal controls (NC) were recruited. Sagittal T2-FLAIR images with 2-mm slice thickness were obtained. Subcallosal dot-dash (SCDD) sign and subcallosal striations (SCS) sign were reviewed. Results: SCDD was more commonly detected in OSMS (28 of 42 patients) than in NMO (5 of 23 patients) (P < 0.05). SCS showed no difference between OSMS (31 of 42 patients) and NMO (12 of 23 patients) (P > 0.05). For comparing ROC analysis among SCDD, SCS, and SCDD + SCS for predicted probability through binary logistic regression analysis, SCDD + SCS had the largest area under ROC curve (0.777) than SCDD (0.725) and SCS (0.608). Conclusion: SCDD may be helpful in distinguishing OSMS from NMO. The regression equation may also be a simple and effective method of choice for the differentiation between OSMS and NMO.

  14. Congenital malformations of the supratentorial brain. Pt. 2. Disorders of the corpus callosum and holoprosencephalies; Kongenitale Malformationen des Grosshirns. Teil 2: Entwicklungsstoerungen des Balkens und Holoprosenzephalien

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    Rummeny, C. [Institut fuer Klinische Radiologie, Klinikum der Universitaet Muenchen, Grosshadern, Muenchen (Germany); Institut fuer klinische Radiologie, Klinikum der Universitaet Muenchen, Grosshadern, Marchioninistrasse 15, 81377, Muenchen (Germany); Ertl-Wagner, B.; Reiser, M.F. [Institut fuer Klinische Radiologie, Klinikum der Universitaet Muenchen, Grosshadern, Muenchen (Germany)

    2003-11-01

    The corpus callosum is formed between the 7th and the 20th gestational week. If this process is disrupted, partial or complete callosal agenesis may ensue. As large parts of the supra- and infratentorial brain are created druing this critical period, associated anomalies need always to be searched for when callosal agenesis is present. Associations with neuro-genetic syndromes also exist. The corpus callosum is generally formed from front to back (''front-to-back rule''). Therefore, a partial callosal agenesis usually involves the posterior portion of the corpus callosum, while a secondary lesion of the corpus callosum does not follow this rule. Holoprosencephalies are a notable exception to this rule, as the frontal part of the corpus callosum is absent in spite of their classification as congenital malformations. They represent a disturbance of the differentiation and cleavage of the prosencephalon with a disruption of the separation of the cerebral hemispheres. Holoprosencephalies can be due to genetic causes, but also to intrauterine infections or other teratogenic causes. The holoprosencephalies are subdivided into alobar, semilobar and lobar holoprosencephalies. This article aims to describe the most important features of callosal agenesis and holoprosencephalies highlighting the respective imaging characteristics. (orig.) [German] Die Anlage des Balkens findet in der 7.-20. Woche nach Gestation statt. Stoerungen in dieser Entwicklungsphase koennen zu einer Balkenagenesie oder zu einer Balkenhypogenesie fuehren. Da in diesem Entwicklungsstadium grosse Anteile des Gross- und Kleinhirns angelegt werden, muss immer nach assoziierten Anlagestoerungen gesucht werden. Ebenso treten auch Kombinationen mit genetisch bedingten Syndromen auf. Die Entwicklung des Balkens folgt der sog. anterioren-posterioren Sequenz (''front-to-back rule''). Sekundaere Schaedigungen bei der Balkenentwicklung folgen dieser Regel nicht, und lassen

  15. Hereditary spastic paraplegia associated with thin corpus callosum Paraplegia espástica hereditária associada a hipoplasia de corpo caloso

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    Hélio A. Ghizoni Teive

    2001-09-01

    Full Text Available Autosomal recessive hereditary spastic paraplegia (AR-HSP associated with thin corpus callosum was recently described in Japan, and most families were linked to chromosome 15q13-15. We report two patients from two different Brazilian families with progressive gait disturbance starting at the second decade of life, spastic paraparesis, and mental deterioration. One patient presented cerebellar ataxia. Magnetic resonance imaging (MRI of the head of both patients showed a thin corpus callosum. AR-HSP with a thin corpus callosum is a rare disorder, mainly described in Japanese patients. We found only 4 Caucasian families with AR-HSP with thin corpus callosum described in the literature. Further studies including additional Caucasian families of AR-HSP with thin corpus callosum are required to delineate the genetic profile of this syndrome in occidental countries.A paraplegia espástica hereditária autossômica recessiva (PEH-AR associada com hipoplasia de corpo caloso foi inicialmente descrita no Japão. Estudos de ligação genética mostram que a maioria das famílias estão relacionadas ao cromossomo 15q13-15. Relatamos dois pacientes de famílias brasileiras, não relacionadas, com distúrbio de marcha com início na segunda década de vida, paraparesia espástica e comprometimento das funções cognitivas. Um dos pacientes apresentava ataxia cerebelar. A ressonância magnética de encéfalo de ambos os pacientes mostrou hipoplasia de corpo caloso. PEH-AR associada com hipoplasia de corpo caloso é uma condição rara, descrita principalmente em pacientes do Japão. Encontramos apenas 4 famílias caucasianas com PEH-AR e hipoplasia de corpo caloso. Mais estudos com famílias caucasianas são necessários para delinear o perfil genético dessa síndrome em países ocidentais.

  16. Progress in endoscopic diagnosis of gastric corpus atrophy%胃体萎缩的内镜诊断

    Institute of Scientific and Technical Information of China (English)

    孟欣颖; 王青

    2011-01-01

    胃体萎缩是较为少见的胃黏膜萎缩,多见于自身免疫性胃炎.胃体萎缩伴肠化生是胃癌的癌前病变.内镜是诊断胃体萎缩的重要手段.本文就胃体萎缩的内镜诊断进展作一综述.%Gastric corpus atrophy is an uncommon type of gastric atrophy, mostly seen in autoimmune gastritis. Gastric corpus atrophy with intestinal metaplasia is considered as premalignant lesion of gastric cancer. Endoscopy is an important method for diagnosis. We will review the advance in endoscopic diagnosis of gastric corpus atrophy.

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

    Science.gov (United States)

    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.

  18. The ciliogenic transcription factor RFX3 regulates early midline distribution of guidepost neurons required for corpus callosum development.

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    Carine Benadiba

    Full Text Available 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.

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

    Science.gov (United States)

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

    2015-04-01

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

  20. Reduced fractional anisotropy of corpus callosum modulates inter-hemispheric resting state functional connectivity in migraine patients without aura.

    Science.gov (United States)

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

    2012-01-01

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

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

    Science.gov (United States)

    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.

  2. Size of corpus callosum in normal subjects and patients with Alzheimer's disease. Magnetic resonance imaging study

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    Yoshii, Fumihito; Duara, R.

    1989-01-01

    The area of the corpus callosum (CC) on midsagittal spin-echo sequence magnetic resonance (MR) scans was measured in 64 normal subjects and 12 patients with Alzheimer's disease (AD). The normal subjects consisted of 32 males and 32 females, aged 25 to 83 years old. There was no significant age difference between males and females. Fifty-five out of the 64 subjects were right-handed (RH) and 9 were left-handed or ambidextrous (NRH). Among patients with AD, 5 were males and 7 were females, aged 53 to 79 years old. Diagnosis of AD was performed mainly based on clinical history, magnetic resonance image (MRI) and positron emission tomographic findings. The outline of the CC on midsagittal MR film was traced and the total callosal sectional area (CCT) as well as the anterior half (CCA), posterior half (CCP) and posterior 5th or splenium (CCS) area measurements were performed using a planimeter. In either normal males or females, the CCA showed a significant negative correlation with age, but the CCP and the CCS did not correlate with age. Total CC (CCT) area was 691.2+-91.0 sq. mm for the whole group and no difference was found between males and females. When the CC area was normalized with respect to the midsagittal area of the supratentorial portion of the brain (MSB), females were found to have a large CC than males. No portion of the CC area was significantly different between RH and NRH subjects in absolute or normalized measures. Compared with 36 age-matched normals, patients with AD had smaller MSB and each portion of the CC, with significant reduction in the CCA and the CCT. In conclusion, relationships between age, sex and the size of the CC have been found, providing some insights into the connectivity of the human brain. Characteristics of white matter loss in AD were also clarified in this study.

  3. Corpus callosum damage predicts disability progression and cognitive dysfunction in primary-progressive MS after five years.

    Science.gov (United States)

    Bodini, Benedetta; Cercignani, Mara; Khaleeli, Zhaleh; Miller, David H; Ron, Maria; Penny, Sophie; Thompson, Alan J; Ciccarelli, Olga

    2013-05-01

    We aim to identify specific areas of white matter (WM) and grey matter (GM), which predict disability progression and cognitive dysfunction after five years in patients with primary-progressive multiple sclerosis (PPMS). Thirty-two patients with early PPMS were assessed at baseline and after five years on the Expanded Disability Status Scale (EDSS), and EDSS step-changes were calculated. At year five, a subgroup of 25 patients and 31 healthy controls underwent a neuropsychological assessment. Baseline imaging consisted of dual-echo (proton density and T2-weighted), T1-weighted volumetric, and diffusion tensor imaging. Fractional anisotropy (FA) maps were created, and fed into tract-based spatial statistics. To compensate for the potential bias introduced by WM lesions, the T1 volumes underwent a lesion-filling procedure before entering a voxel-based morphometry protocol. To investigate whether FA and GM volume predicted EDSS step-changes over five years and neuropsychological tests scores at five years, voxelwise linear regression analyses were performed. Lower FA in the splenium of the corpus callosum (CC) predicted a greater progression of disability over the follow-up. Lower FA along the entire CC predicted worse verbal memory, attention and speed of information processing, and executive function at five years. GM baseline volume did not predict any clinical variable. Our findings highlight the importance of damage to the interhemispheric callosal pathways in determining physical and cognitive disability in PPMS. Disruption of these pathways, which interconnect motor and cognitive networks between the two hemispheres, may result in a disconnection syndrome that contributes to long-term physical and cognitive disability.

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

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    Angelina Paolozza

    2014-01-01

    Full Text Available 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.

  5. The effect of morphological and microstructural integrity of the corpus callosum on cognition, fatigue and depression in mildly disabled MS patients.

    Science.gov (United States)

    Van Schependom, Jeroen; Gielen, Jeroen; Laton, Jorne; Sotiropoulos, Georgios; Vanbinst, Anne-Marie; De Mey, Johan; Smeets, Dirk; Nagels, Guy

    2017-07-01

    To assess the value of callosal morphological and microstructural integrity in assessing different cognitive domains, fatigue and depression in mildly disabled multiple sclerosis (MS) patients. We assessed 29 mildly disabled MS patients and 15 healthy controls using 3T magnetic resonance images (T1-weighted, FLAIR and DTI) and neuropsychological tests assessing different cognitive functions, depression and fatigue. We compared the added value of morphological measures (corpus callosum area corrected for total intracranial volume, index, circularity and the more detailed thickness profile) and diffusion features (fractional anisotropy and mean diffusivity) in multilinear models including standard clinical and whole-brain parameters in assessing neuropsychological scores. Even in mildly disabled MS patients, a significant reduction of the corpus callosum (p<0.001) was observed in comparison to healthy controls. Callosal area, index and circularity were significantly (p<0.002) related to whole-brain white matter volume, T2 lesion load and deep grey matter volume, but not with cortical grey matter. The combination of commonly used imaging and clinical parameters explained between 7% (Fatigue) and 50% (processing speed, verbal memory) of the adjusted variance. Inclusion of the mean diffusivity increased the adjusted R(2) significantly to 69% (p=0.004) and 71% (p=0.002) for visuospatial and verbal memory respectively. Our results show that callosal features may be used as an alternative to measuring whole-brain volumes. Furthermore, the microstructural integrity of the corpus callosum can help to predict an MS patient's memory performance. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Origins and development of corpus callosum and fornix commissures in mice*%胼胝体与穹窿连合纤维的来源与发育

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    吴萍; 邓同兴; 赵慧杰; 李明善; 邓锦波

    2011-01-01

    目的:研究小鼠胼胝体联合和穹窿连合的发生、发育以及细胞来源.方法: 利用快蓝活体示踪和DiI离体示踪技术对不同日龄的胚胎以及生后胼胝体联合和穹窿连合进行了顺行和逆行示踪.结果: 穹窿连合约在胚胎第16天左右形成,而胼胝体连合在胚胎18天左右形成.穹窿连合的纤维主要由海马CA3区锥体细胞、门细胞及内嗅皮质和下托锥体细胞所发出,而胼胝体联合可以由位于新皮质Ⅱ~Ⅵ层神经细胞所投射.结论: 胼胝体连合在细胞来源和分布上的广泛性是大脑半球两侧新皮质之间大量的信息交换的需要.%Objective: To investigate the origin and development of corpus callosum and fornix commissures. Methods: The prenatal and postnatal corpus callosum and fornix commissures at various ages in mice were labeled anterogradely and retrogradely with fast blue tracing in vivo and DiI tracing in vitro. Results: Fornix commissure was formed at embryonic day 16,and corpus callosum commissure was formed at about embryonic day 18. The fibers of fornix rose from the pyramidal cells of CA3, hilus, subiculum and entorhinal cortex. However, fornix fibers were projected by the neurons from layers Ⅱ- Ⅵ of neocortex. Conclusion: The widely cellular distribution of corpus callosum is required of the numerous message communications between two neocortices.

  7. C syndrome with skeletal anomalies, mental retardation, eyelid chalazion, Bitot’s spots and agenesis of the corpus callosum in an Egyptian child

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    Rabah M. Shawky

    2017-01-01

    Full Text Available We report a 2.5 year old female child, third in order of birth of healthy non consanguineous Egyptian parents with C syndrome. The patient had moderate mental retardation, trigonocephaly, protruding forehead, low anterior hair line, wide upslanted palpebral fissures, depressed nasal bridge, broad nose, high arched palate, microretrognathia, low set ears, short neck, scoliosis, hypertrichosis over the back, talipes equinovarus as well as interatrial septal defect. The patient had in addition chalazion in left lower eyelid as well as bilateral Bitot’s spots most probably due to vitamin A deficiency. MRI brain revealed agenesis of the corpus callosum.

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

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    Lombardo Michael V

    2012-11-01

    Full Text Available Abstract 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

  9. Dysgenesis of the corpus callosum and associated malformaaation{sup :} computed tomography and magnetic resonance imaging findings; Disgenesia do corpo caloso e mas-formacoes associadas: achados de tomografia computadorizada e ressonancia magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Montandon, Cristiano; Montandon Junior, Marcelo Eustaquio [Colegio Brasileiro de Radiologia e Diagnostico por Imagem (CBR), Sao Paulo, SP (Brazil); Ribeiro, Flavia Aparecida de Sousa; Lobo, Leonardo Valadares Barbosa; Teixeira, Kim-Ir-Sen Santos [Goias Univ., Goiania (Brazil). Hospital de Clinicas. Dept. de Diagnostico por Imagem e Anatomia Patologica]. E-mail: cabeca2@terra.com.br

    2003-10-01

    Callosal dysgenesis is a malformation of the corpus callosum with origins in the embryogenesis of the telencephalon. We reviewed the computed tomography and magnetic resonance imaging findings of 11 patients with callosal dysgenesis and one patient with normal corpus callosum associated with a lipoma. The patients were divided into three distinct groups: total agenesis (three patients), partial agenesis (six patients) and hypoplasia (two patients). Associated abnormalities were observed in nine patients, including Chiari II malformation (one patient), schizencephaly (one patient), interhemispheric cyst (two patients), Dandy-Walker cyst (one patient), nodular heterotopy (one patient) and lipoma of the corpus callosum (four patients). This paper presents a review that may contribute to the diagnosis of these disorders. (author)

  10. Additional corpus biopsy enhances the detection of Helicobacter pylori infection in a background of gastritis with atrophy

    Science.gov (United States)

    2012-01-01

    Background The best sites for biopsy-based tests to evaluate H. pylori infection in gastritis with atrophy are not well known. This study aimed to evaluate the site and sensitivity of biopsy-based tests in terms of degree of gastritis with atrophy. Methods One hundred and sixty-four (164) uninvestigated dyspepsia patients were enrolled. Biopsy-based tests (i.e., culture, histology Giemsa stain and rapid urease test) and non-invasive tests (anti-H. pylori IgG) were performed. The gold standard of H. pylori infection was defined according to previous criteria. The sensitivity, specificity, positive predictive rate and negative predictive rate of biopsy-based tests at the gastric antrum and body were calculated in terms of degree of gastritis with atrophy. Results The prevalence rate of H. pylori infection in the 164 patients was 63.4%. Gastritis with atrophy was significantly higher at the antrum than at the body (76% vs. 31%; pgastritis with atrophy increased regardless of biopsy site (for normal, mild, moderate, and severe gastritis with atrophy, the sensitivity of histology Giemsa stain was 100%, 100%, 88%, and 66%, respectively, and 100%, 97%, 91%, and 66%, respectively, for rapid urease test). In moderate to severe antrum or body gastritis with atrophy, additional corpus biopsy resulted in increased sensitivity to 16.67% compare to single antrum biopsy. Conclusions In moderate to severe gastritis with atrophy, biopsy-based test should include the corpus for avoiding false negative results. PMID:23272897

  11. Low-cost, rapidly-developed, 3D printed in vitro corpus callosum model for mucopolysaccharidosis type I [version 2; referees: 2 approved

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    Anthony Tabet

    2017-03-01

    Full Text Available 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.

  12. Low-cost, rapidly-developed, 3D printed in vitro corpus callosum model for mucopolysaccharidosis type I [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Anthony Tabet

    2016-12-01

    Full Text Available 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.

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

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    Casaubon, L.K.; Melanson, M.; Marineau, C. [McGill Univ., Quebec (Canada)]|[Montreal General Hospital Research Institute (Canada)] [and others

    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.

  14. Impact of in utero exposure to EtOH on corpus callosum development and paw preference in rats: protective effects of silymarin

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    Montoya Rebecca

    2002-11-01

    Full Text Available Abstract Background Using a rat model we have found that the bioflavonoid silymarin (SY ameliorates some of the negative consequences of in utero exposure to ethanol (EtOH. In the current study our aim was to determine if laterality preference and corpus callosum development were altered in rat offspring whose mothers were provided with a concomitant administration of SY with EtOH throughout gestation. Methods We provided pregnant Fisher/344 rats with liquid diets containing 35% ethanol derived calories (EDC throughout the gestational period. A silymarin/phospholipid compound containing 29.8% silybin was co administered with EtOH to a separate experimental group. We tested the offspring for laterality preference at age 12 weeks. After testing the rats were sacrificed and their brains perfused for later corpus callosum extraction. Results We observed incomplete development of the splenium in the EtOH-only offspring. Callosal development was complete in all other treatment groups. Rats from the EtOH-only group displayed a left paw preference; whereas control rats were evenly divided between right and left paw preference. Inexplicably both SY groups were largely right paw preferring. Conclusions The addition of SY to the EtOH liquid diet did confer some ameliorative effects upon the developing fetal rat brain.

  15. 胼胝体梗死:临床与影像学特征%Corpus callosum infarction: clinical and imaging features

    Institute of Scientific and Technical Information of China (English)

    盛蕾; 胡丹; 肖婧; 张兰坤; 胡君; 王立; 李传游; 丁彩霞; 江雪梅

    2013-01-01

    Objeetive To investigate the clinical and imaging features in patients with corpus callosum infarction.Methods The patients with corpus callosum infarction confirmed by MRI were collected retrospectively.Their clinical manifestations and imaging data were analyzed.Results The corpus callosum infarction accounted for 1.04% of all patients with cerebral infarction.Its major risk factors were hypertension,coronary heart disease,and diabetes.Its typical clinical manifestations included ideomotor apraxia (42.9%),frontal gait (28.6%) and alien hand syndrome (14.3%) accompanied with limb paralysis,disturbance of consciousness,cognitive impairment and other symptoms.MRI detected 8 corpus callosum lesions.Most were involved in the body of corpus callosum (62.5%),followed by splenium (25.0%) and genu (1/8,12.5%).The frontal lobe (57.1%),basal ganglia (42.9%) and occipital lobe (42.9%) were frequently involved.Diffusion tensor imaging revealed that the fiber connections of the body and genu of corpus callosum were broken in one case.Angiography showed that 6 patients had vascular stenosis or occlusion,and the most common was vertebral artery stenosis (66.7%),followed by anterior cerebral artery (50.0%),and common carotid arery,internal carotid artery and middle cerebral artery stenoses were rare (all 33.3%).Conclusions The incidence of corpus callosum infarction is low.Atherosclerosis is the pathogenic key.Its clinical manifestations are diverse,and they are associated with the sites of infarction.%目的 探讨胼胝体梗死患者的临床和影像学特征.方法 回顾性收集经颅脑MRI证实的胼胝体梗死患者,对其临床表现和影像学资料进行分析.结果 胼胝体梗死占所有脑梗死患者的1.04%(7/671),其主要危险因素是高血压、冠心病和糖尿病.典型表现包括观念运动性失用(42.9%)、额叶步态(28.6%)和异己手综合征(14.3%),可伴有肢体瘫痪、意识障碍和认知损害等

  16. Forced abstinence from cocaine self-administration is associated with DNA methylation changes in myelin genes in the corpus callosum: a preliminary study

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    David Andrew Nielsen

    2012-06-01

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

  17. A neonate with the Pelger-Huët anomaly, cleft lip and palate, and agenesis of the corpus callosum, with a chromosomal microdeletion involving 1q41 to 1q42.12.

    Science.gov (United States)

    Christensen, R D; Yaish, H M

    2012-03-01

    We observed a neonate with cleft lip and palate, 13 sets of ribs, agenesis of the corpus callosum, slightly small penis, hypoglycemia, and what initially appeared to be a marked leukocyte 'left shift' on complete blood count, but which was actually a Pelger-Huët anomaly. A chromosomal microdeletion was identified at1q41-42.12.

  18. Corpus callosum of diabetic foot decompression intervention%糖尿病足胼胝减压干预治疗的效果

    Institute of Scientific and Technical Information of China (English)

    王威

    2011-01-01

    Objective To explore the treatment effects of removal of plantar calluses on healing of diabetic foot and preventing its relapse. Methods A total of 452 patients with diabetic foot, 260 cases were under the corpus callosum ulcer with local ulcer infection, in which 161 cases were treated with decompression therapy, and 99 cases did not participate in decompression treatment; 98 of 192 cases were ulcers healed under the corpus callosum continues decompression in treatment, and 94 cases did not participate in decompression treatment. Results Healing time under the corpus callosum and foot clearance combined with infection in decompression treatment group was less than in the non-decompression group (t = - 22. 053, - 64. 568; P <0. 05). 192 ulcer healed cases and 98 decompression cases did not occur ulcer during the observation period.Those 94 cases who did not participate in decompression treatment recurrence local ulcer in short time (6 -42 d). Conclusions Removal of the corpus callosum of diabetic foot can be effective in reducing plantar pressure to promote healing of foot infection and may prevent infection relapse.%目的 探讨足底胼胝去除减压治疗促进糖尿病足愈合及预防感染复发的效果.方法 共452例糖尿病足患者,胼胝下溃疡合并局部溃疡感染者260例参与减压治疗者161例,未参加减压治疗者99例;胼胝下溃疡痊愈后192例继续进行减压治疗者98例,未参加减压治疗者94例.结果 胼胝下感染及合并足间隙感染者减压治疗组较之非减压治疗组其愈合时间明显缩短,组间比较具有统计学意义(t=-22.053,-64.568;P<0.05).胼胝下溃疡痊愈者192例参与减压治疗者98例观察期间未发生局部胼胝下溃疡,未参加减压治疗者94例均在短期内复发,复发时间为6~42 d.结论 去除糖尿病足胼胝可有效减轻足底压力促进足部感染愈合,并可预防感染复发.

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

    Science.gov (United States)

    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.

  20. Lower fractional anisotropy at the anterior body of the normal-appearing corpus callosum in multiple sclerosis versus symptomatic carotid occlusion

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    Lou, Xin; Ma, Lin; Cai, Youquan [PLA General Hospital, Department of Radiology, Beijing (China); Jiang, Weijian; Ma, Ning [Capital University of Medical Sciences, Department of Interventional Neuroradiology, Beijing Tiantan Hospital, Beijing (China); Huang, Dehui [PLA General Hospital, Department of Neurology, Beijing (China); Wong, Edward Hochung [Prince of Wales Hospital, Division of Neurology, Department of Medicine and Therapeutics, Hong Kong (China)

    2009-09-15

    Not uncommonly, differentiating multiple sclerosis (MS) from ischemic cerebral vascular disease is difficult based on conventional magnetic resonance imaging (MRI). We aim to determine whether preferential occult injury in the normal-appearing corpus callosum (NACC) is more severe in patients with MS than symptomatic carotid occlusion by comparing fractional anisotropy (FA) from diffusion tensor imaging (DTI). Eighteen patients (eight men, ten women; mean age, 38.6 years) with MS and 32 patients (24 men, eight women; mean age, 64.0 years) with symptomatic unilateral internal carotid occlusion were included. DTI (1.5 T) were performed at corpus callosum which were normal-appearing on fluid-attenuated inversion recovery MRI. Mean FA was obtained from the genu, anterior body, posterior body, and splenium of NACC. Independent-sample t test statistical analysis was performed. The FA values in various regions of NACC were lower in the MS patients than symptomatic carotid occlusion patients, which was statistically different at the anterior body (0.67{+-}0.12 vs 0.74{+-}0.06, P=0.009), but not at genu, posterior body, and splenium (0.63{+-}0.09 vs 0.67{+-}0.07, P=0.13; 0.68{+-}0.09 vs 0.73{+-}0.05, P=0.07; 0.72{+-}0.09 vs 0.76{+-}0.05, P=0.13). MS patients have lower FA in the anterior body of NACC compared to patients with symptomatic carotid occlusion. It suggests that DTI has potential ability to differentiate these two conditions due to the more severe preferential occult injury at the anterior body of NACC in MS. (orig.)

  1. Cambios en el cuerpo calloso posteriores a derivación ventricular: Descripción de dos casos y revisión del tema Imaging changes in the corpus callosum after ventricular shunting: Case reports and literature review

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    Santiago Vallejo

    2012-09-01

    Full Text Available Se presentan dos pacientes sometidos a derivación ventricular por hidrocefalia idiopática y cisticercosis del cuarto ventrículo, respectivamente. En la resonancia magnética (RM de control se encontró un aumento en el tamaño del cuerpo calloso con zonas de prolongación de los tiempos de relajación sin restricción en la secuencia de difusión. Las teorías fisiopatológicas mencionan: efectos mecánicos directos tras la colocación de la derivación, efecto compresivo crónico sobre el cuerpo calloso contra la hoz cerebral por la hidrocefalia, tracción de ramas perforantes de las arterias pericallosas que conduce a isquemia (probablemente ausente en estudios prequirúrgicos por el adelgazamiento del cuerpo calloso y descompresión, luego de la derivación, que produce reexpansión del cuerpo calloso y edema intersticial del mismo. Los hallazgos pueden explicarse por el antecedente de derivación e hidrocefalia sin repercusión clínica aparente.We report the cases of two patients with ventricular drainage due to idiopathic hydrocephalus and fourth ventricle cysticercosis, respectively. A follow-up MRI demonstrated increased volume of the corpus callosum with areas of prolonged relaxation without restriction on water diffusion sequences. Pathophysiologic theories include direct mechanical effects after the catheter insertion, chronic compression of the corpus callosum against the falx due to hydrocephalus, ischemia due to elongation of perforating pericallosal arteries not detected before shunting due to thinning of the corpus callosum, and decompressive changes leading to corpus callosum expansion and interstitial edema. These findings might be related to the history of ventricular shunt and hydrocephalus with no apparent clinical significance.

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

    Science.gov (United States)

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

    2014-01-01

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

  3. Treatment of refractory seizures due to a benign mass present in the corpus callosum with an ion magnetic inductor: case report.

    Science.gov (United States)

    Mihajlovic-Madzarevic, Vera; Pappas, Panos

    2005-01-01

    A 39-year-old female patient was having episodes of body stiffness that affected her motor abilities. A lipoma in the corpus callosum was identified by computed tomography. Her condition deteriorated rapidly, and seizures were refractory to any treatment. Seizure frequency and severity increased, incapacitating the patient completely. When seizure control was not achieved by any other treatment, the patient decided to undergo experimental therapy with the ion magnetic inductor. Treatment with the ion magnetic inductor notably reduced the seizure frequency and intensity. After treatment the patient was able to return to work and other normal activities. The long-term effects are not yet known, but there have been no adverse events to date. The patient is still undergoing ion magnetic inductor treatment daily in the same way other epileptic patients must continue with the use of antiepileptic drugs for life. There is evidence in the literature that other types of electromagnetic therapy, such as repetitive transcranial magnetic stimulation (rTMS), may be useful for treating refractory seizures. The potential advantage of the ion magnetic inductor over rTMS is that there is no need to locate precisely the epileptogenic focus, making the treatment procedure simpler and faster.

  4. 3D pre- versus post-season comparisons of surface and relative pose of the corpus callosum in contact sport athletes

    Science.gov (United States)

    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.

  5. Selected aspects of social cognition in patient with total agenesis of the corpus callosum (ACC and Arnold-Chiari desease – case study

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    Daniluk, Beata

    2013-06-01

    Full Text Available Aim. The goal of the research was a characteristic of emotional-social competencies and communicative abilities in a 16-years old patient with ACC and Arnold-Chiari disease and higher than average intelligence. Method. RHLB-PL was applied. Results. Total score in RHLB-PL suggested language and communication impairment. The greatest problems were observed in the field of behavioral self-control and discourse abilities. The patient had difficulties in the topic of the discourse maintaining, resisting from production of unconnected topics and comments, interject inappropriate remarks. Problems in humor comprehension and the dissociation between relative high level of written metaphors analysis abilities and low level of Picture Metaphors perception and explanation were observed. Linguistic Prosody was average. Conclusion. Patient M.J. with agenesis of corpus callosum presented high number of deficits typical in right hemisphere damage patients. It is possible to explain that fact in the context of interhemispheric transfer disorders, specially when complex material was processed.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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 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.

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

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    Przemko Kwinta

    2015-01-01

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

  9. The Integrity of the Corpus Callosum Mitigates the Impact of Blood Pressure on the Ventral Attention Network and Information Processing Speed in Healthy Adults

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    Tatia M. C. Lee

    2017-04-01

    Full Text Available Hypertension is a risk factor for cognitive impairment in older age. However, evidence of the neural basis of the relationship between the deterioration of cognitive function and elevated blood pressure is sparse. Based on previous research, we speculate that variations in brain connectivity are closely related to elevated blood pressure even before the onset of clinical conditions and apparent cognitive decline in individuals over 60 years of age. Forty cognitively healthy adults were recruited. Each received a blood pressure test before and after the cognitive assessment in various domains. Diffusion tensor imaging (DTI and resting-state functional magnetic resonance imaging (rsfMRI data were collected. Our findings confirm that elevated blood pressure is associated with brain connectivity variations in cognitively healthy individuals. The integrity of the splenium of the corpus callosum is closely related to individual differences in systolic blood pressure. In particular, elevated systolic blood pressure is related to resting-state ventral attention network (VAN and information processing speed. Serial mediation analyses have further revealed that lower integrity of the splenium statistically predicts elevated systolic blood pressure, which in turn predicts weakened functional connectivity (FC within the VAN and eventually poorer processing speed. The current study sheds light on how neural correlates are involved in the impact of elevated blood pressure on cognitive functioning.

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

    Science.gov (United States)

    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

  11. Progressive decline in fractional anisotropy on serial DTI examinations of the corpus callosum: a putative marker of disease activity and progression in SPMS

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Wei; Zhu, Tong; Zhong, Jianhui; Liu, Xiang [University of Rochester Medical Center, Department of Imaging Sciences, Rochester, NY (United States); Rao, Praveen; Segal, Benjamin M. [University of Michigan, Department of Neurology, Holtom-Garrett Program in Neuroimmunology, Ann Arbor, MI (United States); Ekholm, Sven [University of Rochester Medical Center, Department of Imaging Sciences, Rochester, NY (United States); University of Rochester Medical Center, Division of Diagnostic and Interventional Neuroradiology, Rochester, NY (United States)

    2012-04-15

    Clinical trials of secondary progressive multiple sclerosis (SPMS) is lacking reliable biomarkers or outcome measures that reflect tissue injury incurred within a 1- to 2-year observation period. Diffusion tensor imaging (DTI) is sensitive in detecting acute brain tissue damage. We monitored SPMS patients over 12 months for diffusion changes within the corpus callosum (CC). Bimonthly MRI examinations over a 1-year period were performed on 11 SPMS patients. The protocol included postcontrast T1-weighted images and DTI. Based on the appearance of T1 enhancing lesion(s) during the study period, the patients were divided into enhancing (five patients) and nonenhancing (six patients) groups. Fractional anisotropy (FA) and mean diffusivity (MD) of the genu, body, and splenium of the CC were measured and temporal changes in mean FA and MD were evaluated for each group as well as between groups. Immunology data from peripheral blood mononuclear cells were also collected on a monthly basis. The enhancing group showed significant, progressive decrease in FA in body (p = 0.012) and splenium (p = 0.033) of CC, and significantly higher lymphotoxin-{beta} levels. No significant FA changes were seen in the nonenhancing group. Moreover, the FA decline in the enhancing group deviated significantly from the nonenhancing group, which remained essentially stable. Although MD increased slightly in both groups, there was no significant difference between the two groups. Based on the MR and immunology findings, the results of our study suggest that DTI undergo more rapid and longitudinal changes in SPMS patients with inflammatory activity. (orig.)

  12. Clinical, neuroimaging and cytogenetic findings in 20 patients with corpus callosum dysgenesis Achados clínicos, citogenéticos e de neuroimagem em 20 pacientes com disgenesia do corpo caloso

    Directory of Open Access Journals (Sweden)

    Anna Cláudia Evangelista dos Santos

    2002-06-01

    Full Text Available Twenty children with corpus callosum agenesis or hypoplasia were evaluated under a standardized investigation protocol. Psychomotor retardation, seizures, and craniofacial anomalies were the most prominent findings. There were three cases of chromosomal anomalies, all of them representing trisomy of chromosome 8.Vinte pacientes com disgenesia do corpo caloso foram avaliados através de um protocolo padronizado. Retardo neuropsicomotor, convulsões e dismorfias faciais foram os achados mais proeminentes. Três casos de anomalia cromossômica foram observados, todos representados por trissomia do cromossomo 8.

  13. Agenesis of the Corpus Callosum

    Science.gov (United States)

    ... Translational Research Research at NINDS Focus on Research Alzheimer's & Related Dementias Bioengineering Epilepsy Health Disparities Neural Interfaces Parkinson's Disease Spinal Cord Injury Stem Cells Traumatic Brain Injury Trans-Agency Activities Interagency Research ...

  14. Clinical Analysis on Reversible Splenial Lesions of the Corpus Callosum%可逆性胼胝体压部病变的临床分析

    Institute of Scientific and Technical Information of China (English)

    胡小辉; 姚长江; 汤前军; 刘智舒

    2012-01-01

    Objective To evaluate the clinical characteristics and pathophysiological mechanism of reversible splenial lesions of the corpus callosum (RSLCC). Methods The patients with RSLCC and older than 6 years were screened from "Pubraed" and "Springer" databases for analysis between January 1, 2000 and August 1, 2011. We analyzed their clinical characteristics and the pathophysiological mechanisms. Results The mean age of 14 RSLCC patients, including 7 males and 7 females, were (27.4 ± 15.6) years, ranging from 7 to 58 years. Causes of the disease in these patients were fever, vaccination injection, infection, seizure, anti-epileptic drug or acute withdrawal of antiepileptic drug, tetracycline therapy, 5-fluorouracil treatment, malnutrition, chronic alcoholism. The appearance rate of clinical representations was 50%, which included visual hallucinations, delusion, disorientation, confusion, gait ataxia, acute urinary retention. The mean interval to disappearance of RSLCC was (20.6 ± 14.5) days, ranging from 2 to 50 days. The magnetic resonance imaging of abnormality in RSLCC were hypo- or isointense on T1 weight imaging (T1WI) without Gd-enhancement, hyperintense on T2 weight imaging (T2WI) and diffusion-weighted imaging (DWI) with or without fluid-attenuated inversion recovery (FLAIR), hypointense on apparent diffusion coefficient (ADC). Conclusions The causes of RSLCC are diverse. The representations of RSLCC are complicated. The pathophysiological mechanism is cytotoxic edema probably caused by hyponatremia, hypoglycemia, dysfunction of arginine-vasopressin or infectious and toxic agents to splenial of the corpus callosum.%目的 探讨可逆性胼胝体压部病变的临床特征和致病机制.方法 总结Pubmed和Springer数据库中2000年1月1日-2011年8月1日报道的年龄>6岁的可逆性胼胝体压部病变患者的临床特征,分析该病可能的致病机制.结果 14例患者中男7例,女7例;年龄(27.4±15.6)岁,最小7岁,最大58岁;病

  15. 遗传性痉挛性截瘫伴薄胼胝体6例报道并文献复习%Hereditary spastic paraplegia with thin corpus callosum(6 case report and literature review)

    Institute of Scientific and Technical Information of China (English)

    马凌燕; 万新华; 王琳; 徐蔚海; 杨英麦

    2012-01-01

    Objective To investigate the pathogenesis, clinical characteristics, imaging changes and prognosis of hereditary spastic paraplegia with thin corpus callosum (HSP-TCC), Methods Clinical presentation and imaging features of six patients with hereditary spastic paraplegia and thin carpus callosum were reported. The clinical features were summarized and the related literatures were reviewed. Results All six cases had a juvenile onset, presenting with spastic gait, tendon hyperreflexia and positive Babinski sign and without sensory disturbance. Two cases showed ataxia. No one had urination and defecation function disturbance. Conclusions HSP-TCC is a type of complicated forms of hereditary spastic paraplegia (HSP) and is characterized with spastic paraplegia and thin corpus callosum. The pathogenesis is unclear and the prognosis is poor.%目的 探讨遗传性痉挛性截瘫伴薄胼胝体(HSP-TCC)的发病机制、临床特点、影像学表现及预后.方法 分析6例HSP-TCC患者的临床及影像学表现,结合文献复习总结其临床特征.结果 6例患者均青少年起病,表现为痉挛步态,腱反射亢进,病理征阳性,2例有共济失调.患者均无感觉障碍及大小便障碍.全部患者头颅MRI显示胼胝体变薄.结论 HSP-TCC作为复杂型遗传性痉挛性截瘫(HSP)的一种,临床上以双下肢痉挛性截瘫和薄胼胝体为特征,发病机制尚不清楚,预后较差.

  16. MRI显示的儿童胼胝体压部孤立性病变的临床特征分析%The clinical characteristics of children with splenium of corpus callosum solitary lesions displayed on MRI

    Institute of Scientific and Technical Information of China (English)

    李朝阳; 李春花; 杨洁

    2014-01-01

    Objective To explore the prominent clinical features and the prognosis of corpus callosum solitary lesions cases in children.Methods There were 16 cases with corpus callosum solitary lesions receiving treatment at our hospital from January to December 2013.All of the clinical features were collected and retrospectively analyzed.Results The 16 cases aged 1 year to 13 years with an average age of (3.44 ± 3.65) years.The causes of the disease included the viral encephalitis,convulsions,and rotavirus infection.The most prevalent disorders were convulsions (10 cases),gastrointestinal symptoms (8 cases),fever (8 cases),positive cervical resistance (6 cases),fatigue (5 cases),altered states of consciousness (2 cases),headache (1 case),and dizziness (1 case).Corpus callosum lesions lasted for 13-50 days,with an average of (28.8 ± 10.2) days.Cranial magnetic resonance showed the splenium of the corpus callosum with isolated oval lesions,low signal on T1 weighted images and apparent diffusion coefficient images,high signal on T2 weighted images and diffusion weighted images.Conclusions The splenium of the corpus callosum lesions of children occur in a lower rate than adults with the etiology including intracranial infection,convulsions and rotavirus infection.Main clinical manifestations include fever,convulsions and gastrointestinal symptoms (nausea,diarrhea,etc).The cases followed-up showed the lesions and symptoms are reversible,and the prognosis is good.%目的 探讨儿童胼胝体压部病变的临床特征及预后.方法 回顾性分析2013年1-12月山西省儿童医院神经内科收治的胼胝体压部病变患者的临床特征及预后,分析该病可能的致病机制.结果 16例患者中,男性8例,女性8例;年龄1 ~13岁,平均(3.44±3.65)岁;病因分为病毒性脑炎、抽搐、轮状病毒感染等;出现的临床症状包括抽搐(10例)、消化道症状(8例)、发热(8例)、颈抵抗阳性(6例)、精神萎靡(5例)、意识改变(2

  17. Association between Cognitive Impairment and Corpus Callosum Network Connectivity in Leukoaraiosis%胼胝体网络连接性与脑白质疏松认知功能损害的相关性

    Institute of Scientific and Technical Information of China (English)

    何育生; 江虹; 李云霞; 腾飞; 聂志余

    2016-01-01

    目的通过弥散张量成像(diffusion tensor imaging,DTI)研究脑白质疏松(leukoaraiosis,LA)患者胼胝体网络连接性改变,并探讨其与认知功能损害的关系。  方法本研究为前瞻性单中心研究。纳入30例法泽卡斯量表(Fazekas scale)评分为2~3级的LA患者及20例头部磁共振成像正常的对照组。依据是否存在认知功能损害将LA组再分为认知正常与轻度认知功能损害2个亚组。所有被研究对象均进行脑血管危险因素登记、血液生化检查、认知功能评估筛查及3.0T头部磁共振成像检查及DTI检查。认知评估采用中文版蒙特利尔认知评估(Montreal Cognitive Assessment,MoCA)量表及简易智力状况检查(Mini-mental State Examination,MMSE)量表。使用PANDA软件处理DTI数据,提取胼胝体膝部、体部及压部的部分各向异性(fractional anisotropy,FA)和平均扩散系数(mean diffusivity,MD)数值。采用Pearson相关分析研究DTI数据变化与认知功能损害的关系。  结果 LA组与对照组的性别、年龄、受教育情况、脑血管病常规危险因素及血生化之间差异无显著性,P>0.05。LA组的MMSE及MoCA分值低于对照组,P值分别为0.002和0.008。LA组胝体膝部(P=0.000)、体部(P=0.000)、压部(P=0.026)3个部位的FA值均低于对照组,而MD值高于对照组,P值分别为0.013、0.006及0.007。LA组MMSE及MoCA分值降低与胼胝体膝部、体部、压部的FA下降均成正相关,但相关系数从膝部(r=0.78)到压部(r=0.41)呈现逐渐递减趋势。  结论 L A存在胼胝体网络连接性改变,胼胝体FA下降与认知功能损害密切相关。%Objective To study the changes of corpus callosum network connectivity in leukoaraiosis (LA) patients by diffusion tensor imaging (DTI), and investigate the association between this change and cognitive impairment. Methods This study is a single

  18. NT5C2 novel splicing variant expands the phenotypic spectrum of Spastic Paraplegia (SPG45): case report of a new member of thin corpus callosum SPG-Subgroup.

    Science.gov (United States)

    Elsaid, Mahmoud F; Ibrahim, Khalid; Chalhoub, Nader; Elsotouhy, Ahmed; El Mudehki, Noora; Abdel Aleem, Alice

    2017-03-21

    Hereditary Spastic Paraplegia (HSP) is a genetically heterogeneous group of neurodegenerative diseases. Thin Corpus Callosum (TCC) associated HSP is a distinguished subgroup of complex forms. Purines and pyrimidine, the basic DNA and RNA components, are regulating the cell metabolism, having roles in signal transduction, energy preservation and cellular repair. Genetic defects in nucleotide metabolism related genes have been only recently implicated in brain and neurodegenerative diseases' pathogenesis. We present a consanguineous Qatari family with two brothers, 9 and 3 years, who displayed a characteristic phenotype of early onset and markedly-severe spasticity with tiptoe walking, delayed dysarthric speech, persistent truncal hypotonia, and multiple variable-sized areas of brownish skin discoloration appearing at different places on the body. A clinical diagnosis suggestive of complex hereditary spastic paraplegia (HSP) was set after the family had the second affected child. Whole genome sequencing identified a novel homozygous NT5C2 splice site mutation (NM_012229.4/NM_001134373.2: c.1159 + 1G > T) that recessively segregated in family members. Brain MRI revealed dysgenic and thin corpus callosum (TCC) with peri-trigonal white matter cystic changes in both affected boys, whereas a well-developed corpus callosum with normal white matter was shown in their apparently normal brother, who found to be a carrier for the mutant variant. This mutation led to skipping of exon 14 with removal of 58 amino acid residues at the C-terminal half. The aberrantly spliced NT5C2 showed substantial reduction in expression level in the in-vitro study, indicating marked instability of the mutant NT5C2 protein. The present report expands the phenotypic spectrum of SPG45 and confirms NT5C2-SPG45 as a member of the rare TCC SPG-subtypes. Homozygous alteration in NT5C2 seems essential to produce central white matter developmental defects. The study highlights the importance of

  19. 高岭土诱导大鼠脑积水模型的建立和监测%Kaolin- induced hydrocephalus in the rat: temporal sequence of changes in weight, intracranial pressure, ventriculomegaly and corpus callosum thickness

    Institute of Scientific and Technical Information of China (English)

    卫永旭; 王伟军; 宋菡姝; 靳世辉; 高瑞庭; 初明; 蔺友志

    2012-01-01

    Objective To develop models of kaolin - induced hydrocephalus in adult Wistar rats and to measure changes of body weight,intracranial pressure,ventriculomegaly and corpus callosum thickness.Methods 60 adult male Wistar rats were randomly divided into experimental group and control group.In the former group,40 rats were randomly separated into 5 subgroups:group A,B,C,D and E,then were used to construct animal models of hydrocephalus by injecting 0.1 ml volume of 25% kaolin sterile solution into the cisterna Magana with the aid of a surgical microscope.Controls were trcatcd in the same way with injection of saline.Body weighing,MRI and ICP were performed at the tine point of 3 days,1,2,4 and 8 weeks after kaolin injection,respectively.Corpus callosum thickness was measured at the level of the optic chiasm.Results Hydrocephalus was induced in 23 rats whose ventricular system expauded as times went on.In hydrocephalus rats,body weight was significantly lower than in age - matched saline - injected sham controls,ICP increased rapidly on day 3 post intracisternal kaolin injection,reached a maximum on day 7,remained markedly elevated through 8 week, and had reduced corpus callosum thickness as ventricle enlargment.Conclusions Kaolin injection through cistern magna can effectively eatablish a rat model of communicating hydrocephalus.Aherations in ICP,ventriculomegaly and corpus callosum thickness occurs sequentially,and the time - course of each manifestation of hydrocephalus differs.%目的 高岭土诱导Wistar大鼠脑积水后系统监测大鼠体质量、颅内压、脑室面积和胼胝体厚度的改变.方法 雄性Wistar大鼠60只,按随机数字表顺序分为实验组(n=40)和对照组(n=20).实验组40只大鼠再随机分为A、B、C、D、E五个亚组,向枕大池内注入25%无菌高岭土混悬液0.1 ml;对照组注入等量无菌生理盐水,注入后3d、1周、2周、4周和8周后行体质量、MRI检查及颅内压监测,经视交叉切

  20. 产前三维超声TUI技术对胎儿胼胝体发育不全的诊断价值%Value of Tomographic Ultrasound Imaging in Prenatal Diagnosis of Fetal Agenesis of the Corpus Callosum

    Institute of Scientific and Technical Information of China (English)

    林琪; 范海波; 甘晗靖; 孙枫; 吴瑛

    2013-01-01

    Objective To analyze the graphic features of fetal agenesis of the corpus callosum (ACC) detected by tomographic ultrasound imaging(TUI) and assess the value of TUI in the ACC. Methods 3D volume data of 35 cases of fetus with ACC were analyzed with TUI,the sagittal plane median view of the brain was obtained and the outcome was compared with that of two-dimensional (2D) ultrasound. Results There was difference in the revealing rate of ACC between TUI and 2D ultrasound(P<0. 05). Conclusions TUI is a useful tool in the prenatal diagnosis of ACC.%目的 分析三维断层超声显像技术(tomographic ultrasound imaging,TUI)在胎儿胼胝体发育不全(agenesis of the corpus callosum,ACC)中的图像特征,评价TUI诊断胎儿胼胝体发育不全的价值.方法 应用TUI对34例二维可疑ACC的三维容积数据进行后处理分析,获得显示胼胝体最好的胎头正中矢状切面,并将结果与二维超声结果进行比较.结果 TUI技术对ACC的显示率为97.0% (33/34);二维超声对ACC的显示率为52.9% (18/34),二者的显示率差别有统计意义(P<0.05).结论 三维超声TUI技术在胎儿ACC的产前诊断上具有较高的应用价值.

  1. Study of age and sex differences of genu and rostrum of corpus callosum by using diffusion tensor imaging of MRI in normal person%正常人胼胝体膝部及嘴部年龄与性别差异的DTI研究

    Institute of Scientific and Technical Information of China (English)

    卢姿蓉; 邹松; 李振龙; 赵英杰

    2012-01-01

    目的:研究胼胝体膝部和嘴部的DTI参数ADC值、部分各项异性(FA)值及神经密度在年龄及性别方面的差异,并获取其随年龄增长的变化规律.方法:将247例正常人按照年龄段分为10组,行颅脑DTI,测量胼胝体膝部和嘴部ROI的ADC值、FA值及神经纤维数,并计算神经密度.结果:①男性胼胝体膝部和嘴部的ADC值随年龄增长的差异均具有统计学意义;女性则差异均无统计学意义.②男性及女性胼胝体膝部和嘴部的FA值随年龄增长差异均具有统计学意义,其随年龄增长的变化规律基本上符合升高—相对稳定—下降的趋势.③男性及女性的胼胝体膝部和嘴部神经密度随年龄增长差异均无统计学意义.④在>3~6岁组,女性胼胝体嘴部的ADC值显著高于男性(P<0.01);在40岁以上男性,胼胝体膝部的神经密度显著高于女性(P<0.01);胼胝体膝部的ADC值和FA值、胼胝体嘴部的FA值和神经密度在各个年龄段内的性别差异均无统计学意义.结论:①胼胝体膝部和嘴部的ADC值、FA值随年龄增长的变化规律可以反映胼胝体膝部和嘴部生长发育及老化的整个过程.②本研究所获得的胼胝体膝部和嘴部的ADC值、FA值及神经密度可作为以后进一步研究的参考.%Objective: To research the differences of MRI ADC value, FA value and nerve density of the genu and rostrum of corpus callosum in the aspects of age and sex,and obtain the change laws with age. Method:247 normal persons were classified into ten groups according to their age and their heads were examined with DTI and DTT of MRI. The ADC value,FA value and nerve fiber number of the ROIs of genu and rostrum of corpus callosum were measured,and then the nerve density was calculated. Results;①There were significant differences in the ADC values of genu and rostrum of corpus callosum of males with age. The ADC values of genu and rostrum of corpus callosum of females had no

  2. The role of prenatal ultrasound and MRI in diagnosis of fetal agenesis of corpus callosum%胎儿胼胝体缺如产前超声及磁共振诊断的应用分析

    Institute of Scientific and Technical Information of China (English)

    兰为顺; 杨小红; 夏薇; 刘芳; 余旭东; 袁先宏; 李琳; 苏永学; 杨文忠; 陈欣林

    2015-01-01

    目的分析胎儿胼胝体缺如的产前超声及磁共振诊断价值。方法对2013年7月至2014年12月湖北省妇幼保健院产前超声筛查怀疑胼胝体缺如的67例胎儿于超声检查后3 d内行颅脑磁共振检查,与引产或出生后检查结果对照,对产前超声及磁共振检查结果进行分析。结果产前超声怀疑胼胝体缺如的67例胎儿磁共振检查后均证实为胼胝体缺如,其中胼胝体完全缺如58例,胼胝体部分缺如9例(均为胼胝体体部和压部缺如)。胎儿胼胝体缺如在磁共振正中矢状位图像上表现为胼胝体完全或部分缺如,脑回呈放射状排列;在横轴位和冠状位图像上表现为侧脑室轻至中度扩张,形态失常。结论磁共振对胎儿胼胝体缺如有较高的诊断价值,可作为产前超声的补充和验证方法,在产前超声检查怀疑胎儿胼胝体异常时,应行胎儿磁共振检查明确诊断。超声与磁共振联合筛查,是胎儿中枢神经系统畸形产前检查中重要的影像学诊断方法。%Objective To discuss the value of prenatal ultrasound and MRI in diagnosis of fetal agenesis of corpus callosum (ACC). Methods Sixty-seven fetuses from Hubei Maternal and Children's Hospital performed fetal MRI from July 2013 to December 2014 were included in this study. All fetuses (67 cases) with suspected ACC were studied with a 1.5T MR unit within 3 days after ultrasound examination. Prenatal ultrasound and MRI findings were studied. Results All the 67 ACCs previously suspected on ultrasound were confirmed by MRI. Among the 67 ACCs, 58 cases were complete ACC and 9 cases were partial ACC. Corpus callosum body and/or splenium absence was found in all 9 partial ACC cases. In all cases, on MRI, corpus callosum complete or partial absence was showed on the median sagittal images, and mild to moderate ventriculomegaly and abnormal morphology in lateral ventricle was shown on the axial or coronary images

  3. 胎儿胼胝体发育不全的超声诊断及临床分析%The Ultrasonographic Diagnosis of Fetal Corpus Callosum Agenesis and Clinical Analysis

    Institute of Scientific and Technical Information of China (English)

    程桂静; 杨太珠; 徐红; 张波

    2012-01-01

    Objective To investigate the ultrasonographic characteristics, cerebral and extracerebral malformation, chromosomal abnormality and prognosis of fetal corpus callosum agenesis( ACC). Methods 36 cases of fetal ACC were retrospectively analyzed from January 2008 to April 2011 in our hospital. Results 36 cases of fetal ACC were diagnosed by ultrasonography, with 19 cases combined other parts of malformation. The diagnostic results with MRI were as the same as with ultrasound in 4 cases. 31 cases were performed Down syndrome screening, which were high risk in 16 cases. 12 cases were performed chromosomal screening, with 1 case of 18 - trisomy and 1 case of inv 9. In the following up, 29 cases were performed induced abortion, 4 cases were birth, and 3 cases were lost of follow up. Conclusions The fetal ACC is often associated with other parts of malformation, prenatal ultrasonic examination can make the preliminary diagnosis for this disease. When ultrasonographic diagnosis of this disease is not clear, MRI can be used as auxiliary method to provide effective clinical information, which can provide the evidence for making suitable decision.%目的 探讨胎儿胼胝体发育不全(agenesis of corpus callosum,ACC)的超声特点、合并的颅内外畸形、染色体及预后状况.方法 回顾性分析我院2008年1月~2011年4月产前超声诊断为胎儿ACC的胎儿共36例.结果 超声诊断为胎儿ACC 36例,其中19例合并其他部位畸形;4例孕妇行核磁共振检查,其结果与超声诊断一致;31例行唐氏筛查,16例为唐氏高风险;12例行染色体检查,1例18-三体综合征,1例9号臂间倒位核型(inv 9).随访结果中,29例进行了引产,4例出生,3例失访.结论 胎儿ACC常合并其他部位的畸形,产前超声检查能够为胎儿ACC作出初步诊断,当超声不能明确诊断时,MRI可以作为辅助检查方法,为制定适合的决策提供依据.

  4. Comparative analysis of ultrasonic and MRI in diagnosis of fetal agenesis of corpus callosum%超声及MRI诊断胎儿胼胝体发育不全的对比分析

    Institute of Scientific and Technical Information of China (English)

    邹丽华; 康敏; 杨家翔; 赵婧; 石涛

    2014-01-01

    目的 探讨产前超声对胎儿胼胝体发育不全(agenesis of the corpus callosum,ACC)的诊断价值及临床意义.方法 对超声诊断胼胝体发育不全的17例胎儿,结合核磁共振(MRI)、出生后或引产结果进行分析比较.结果 17例超声诊断完全型ACC 6例,部分型ACC 11例;2例完全型ACC及1例部分型ACC的超声结论与MRI检查结果一致,5例完全型ACC及7例部分型ACC与引产或出生后结果一致;13例行染色体检查,4例染色体异常;9例合并其它畸形或多种畸形并存.结论 产前超声检查对诊断胎儿ACC特别是完全型ACC具有一定的优势,胎儿ACC常合并其它畸形,MRI是诊断胎儿ACC的必要手段.

  5. MRI study on corpus callosum atrophy in alzheimer disease%Alzheimer病胼胝体萎缩的MRI定量研究

    Institute of Scientific and Technical Information of China (English)

    张雪宁; 陈希颖

    2002-01-01

    目的:评价胼胝体面积测量对诊断Alzheimer病(Alzheimer disease,AD)的价值.方法:14名AD患者和20名年龄、性别、受教育程度相匹配的正常对照,进行MRI扫描并全部行简易精神状态量表(MMSE)检查.结果:AD组胼胝体面积区域性减少,胼胝体萎缩与AD的认知功能损害显著相关.结论:胼胝体面积的测量可以有助于AD的明确诊断.

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

    Science.gov (United States)

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

    2010-10-01

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

  7. 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.

    Science.gov (United States)

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

    2017-04-15

    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

  8. Mucosal patterns of Helicobacter pylori-related gastritis without atrophy in the gastric corpus using standard endoscopy

    Institute of Scientific and Technical Information of China (English)

    Shwu-Tzy; Wu; Chien-Hua; Chen; Yeh-Huang; Hung; Tsung-Hsun; Yang; Vun-Siew; Pang; Yung-Hsiang; Yeh

    2010-01-01

    AIM:To identify the mucosal patterns of Helicobacter pylori(H.pylori )-related gastritis in the gastric corpus using standard endoscopy and to evaluate their reproducibility.METHODS:A total of 112 consecutive patients underwent upper gastrointestinal endoscopy.The endoscopists classified the endoscopic findings into 4 patterns.In the second part of the study,90 images were shown to 3 endoscopists in order to evaluate the inter-observer and intra-observer variability in image assessment.RESULTS:The mucosal p...

  9. Disgenesia do corpo caloso e más-formações associadas: achados de tomografia computadorizada e ressonância magnética Dysgenesis of the corpus callosum and associated malformations: computed tomography and magnetic resonance imaging findings

    Directory of Open Access Journals (Sweden)

    Cristiano Montandon

    2003-10-01

    Full Text Available O termo disgenesia do corpo caloso refere-se a uma má-formação deste com origem na embriogênese do telencéfalo. O relato analisa os achados de tomografia computadorizada e ressonância magnética em 11 pacientes com disgenesia calosa e em um caso de corpo caloso normal com lipoma associado. Esta pode ser distinguida em três grupos: agenesia total (três casos, agenesia parcial (seis casos e hipoplasia (dois casos. Anomalias associadas foram observadas em nove casos, incluindo má-formação de Chiari tipo II (um caso, esquizencefalia (um caso, cisto inter-hemisférico (dois casos, heterotopia nodular (um caso, cisto de Dandy-Walker (um caso e lipoma do corpo caloso (quatro casos. Este artigo demonstra um espectro destes distúrbios, auxiliando na sua interpretação diagnóstica.Callosal dysgenesis is a malformation of the corpus callosum with origins in the embryogenesis of the telencephalon. We reviewed the computed tomography and magnetic resonance imaging findings of 11 patients with callosal dysgenesis and one patient with normal corpus callosum associated with a lipoma. The patients were divided into three distinct groups: total agenesis (three patients, partial agenesis (six patients and hypoplasia (two patients. Associated abnormalities were observed in nine patients, including Chiari II malformation (one patient, schizencephaly (one patient, interhemispheric cyst (two patients, Dandy-Walker cyst (one patient, nodular heterotopy (one patient and lipoma of the corpus callosum (four patients. This paper presents a review that may contribute to the diagnosis of these disorders.

  10. Clinical Correlates of Corpus Callosal Agenesis

    OpenAIRE

    J Gordon Millichap

    1998-01-01

    The clinical correlates of agenesis of the corpus callosum were examined in 56 cases (37 adult, 19 pediatric) reported to the British Neurological Surveillance Unit (BNSU) and surveyed at the Department of Psychological Medicine, Institute of Psychiatry, London, UK.

  11. Corpus Callosum Morphology in Children Who Stutter

    Science.gov (United States)

    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. 胎儿胼胝体发育不良的超声和磁共振对比观察%Comparison of ultrasound and MRI in the prenatal diagnosis of agenesis of corpus callosum

    Institute of Scientific and Technical Information of China (English)

    姜小力; 邓学东; 李晓兵

    2011-01-01

    Objective To observe the value of ultrasound (US) and MRI in the prenatal diagnosis of agenesis of corpus callosum (ACC).Methods Fetal ACC was suspected in 16 pregnant women by prenatal US.Fetal MRI was performed within 3 days after prenatal US.The findings of prenatal US and fetal MRI were compared with the results of autopsy or following up imaging data after birth.Results Sixteen fetuses were detected in 16 pregnant women.Fourteen fetuses of ACC suspected with prenatal US were confirmed with MRI (5 confirmed with following-up after birth and 9 with autopsy).Another 2 fetuses were not ACC, 1 was ventriculomegaly companying with gray matter translocation and the other was cerebral white matter and brain stem hypoplasia.Of all the fetal ACC confirmed with MRI, US was consistent with MRI in 7 fetuses, and other 7 fetuses were suspected with US.For the other associated abnormalities in central nervous system,MRI was consistent with prenatal US in 7 fetuses.MRI demonstrated more associated abnormalities than US in 4 fetuses.Conclusion US is the optimal choice for detecting fetal anomalies.However, MRI is superior to US in the diagnosis of ACC and contributes to the definite diagnosis of ACC and possible associated abnormalities.%目的 探讨超声与MRI在胎儿胼胝体发育不良(ACC)产前诊断中的应用价值.方法 超声怀疑胎儿ACC孕妇16名,均在超声检查后3天内接受胎儿MR检查.将超声、MRI结果与出生后或引产后结果对照.结果 16名孕妇共检出胎儿16胎,MRI证实14胎为胎儿ACC(出生后随访证实5胎,引产后证实9胎),1胎为单纯双侧脑室扩张伴灰质易位,1胎为脑白质、脑干发育不良.MRI与超声比较,诊断胎儿ACC一致者7胎;超声可疑、MRI肯定者7胎;对于其伴发中枢神经系统畸形,两者一致者7胎,MRI多于超声者4胎.结论 超声检查是产前筛查胎儿ACC的普遍方法;MRI对胎儿ACC的显示明显优于超声,有助于明确诊断胎儿ACC并判断其分型及合并畸形.

  13. Isolated complete corpus callosal agenesis

    OpenAIRE

    Jaiganesh S, Venkateshwaran A, Naresh Kumar C, Rajasekhar KV

    2014-01-01

    Isolated complete corpus callosal agenesis is a rare entity. Usually this condition will be an associated finding in other syndromes. 3 month old male child came with complaints of deformed foot on both sides, not having a social smile and neck holding. Patient referred to the Radiology department for MRI brain which showed complete absence of corpus callosum, widely separated and parallely placed lateral ventricles, colpocephaly, high riding of 3rd ventricle and absence of cingulate gyrus an...

  14. Isolated complete corpus callosal agenesis

    Directory of Open Access Journals (Sweden)

    Jaiganesh S, Venkateshwaran A, Naresh Kumar C, Rajasekhar KV

    2014-11-01

    Full Text Available Isolated complete corpus callosal agenesis is a rare entity. Usually this condition will be an associated finding in other syndromes. 3 month old male child came with complaints of deformed foot on both sides, not having a social smile and neck holding. Patient referred to the Radiology department for MRI brain which showed complete absence of corpus callosum, widely separated and parallely placed lateral ventricles, colpocephaly, high riding of 3rd ventricle and absence of cingulate gyrus and radial arrangement of gyri along the interhemispheric fissure. Hence it was reported as isolated complete corpus callosal agenesis and this article describes the Embryogenesis, anatomy, developmental anomalies and its clinical manifestations & prognosis.

  15. White matter atrophy and cognitive dysfunctions in neuromyelitis optica.

    Directory of Open Access Journals (Sweden)

    Frederic Blanc

    Full Text Available Neuromyelitis optica (NMO is an inflammatory disease of central nervous system characterized by optic neuritis and longitudinally extensive acute transverse myelitis. NMO patients have cognitive dysfunctions but other clinical symptoms of brain origin are rare. In the present study, we aimed to investigate cognitive functions and brain volume in NMO. The study population consisted of 28 patients with NMO and 28 healthy control subjects matched for age, sex and educational level. We applied a French translation of the Brief Repeatable Battery (BRB-N to the NMO patients. Using SIENAx for global brain volume (Grey Matter, GM; White Matter, WM; and whole brain and VBM for focal brain volume (GM and WM, NMO patients and controls were compared. Voxel-level correlations between diminished brain concentration and cognitive performance for each tests were performed. Focal and global brain volume of NMO patients with and without cognitive impairment were also compared. Fifteen NMO patients (54% had cognitive impairment with memory, executive function, attention and speed of information processing deficits. Global and focal brain atrophy of WM but not Grey Matter (GM was found in the NMO patients group. The focal WM atrophy included the optic chiasm, pons, cerebellum, the corpus callosum and parts of the frontal, temporal and parietal lobes, including superior longitudinal fascicle. Visual memory, verbal memory, speed of information processing, short-term memory and executive functions were correlated to focal WM volumes. The comparison of patients with, to patients without cognitive impairment showed a clear decrease of global and focal WM, including brainstem, corticospinal tracts, corpus callosum but also superior and inferior longitudinal fascicles. Cognitive impairment in NMO patients is correlated to the decreased of global and focal WM volume of the brain. Further studies are needed to better understand the precise origin of cognitive impairment in

  16. Tract-specific atrophy in focal epilepsy: Disease, genetics, or seizures?

    Science.gov (United States)

    Vaughan, David N; Raffelt, David; Curwood, Evan; Tsai, Meng-Han; Tournier, Jacques-Donald; Connelly, Alan; Jackson, Graeme D

    2017-02-01

    To investigate whether genetics, underlying pathology, or repeated seizures contribute to atrophy in specific white matter tracts. Medically refractory unilateral temporal lobe epilepsy (TLE) with hippocampal sclerosis (HS-TLE, n = 26) was studied as an archetype of focal epilepsy, using fixel-based analysis of diffusion-weighted imaging. A genetic effect was assessed in first-degree relatives of HS-TLE subjects who did not have epilepsy themselves (HS-1°Rel; n = 26). The role of disease process was uncovered by comparing HS-TLE to unilateral TLE with normal clinical magnetic resonance imaging (MRI-neg TLE; n = 26, matched for seizure severity). The effect of focal seizures was inferred from lateralized atrophy common to both HS-TLE and MRI-neg TLE, in comparison to healthy controls (n = 76). HS-1 °Rel had bilaterally small hippocampi, but no focal white matter atrophy was detected, indicating a limited effect of genetics. HS-TLE subjects had lateralized atrophy of most temporal lobe tracts, and hippocampal volumes in HS-TLE correlated with parahippocampal cingulum and anterior commissure atrophy, indicating an effect of the underlying pathology. Ipsilateral atrophy of the tapetum, uncinate, and inferior fronto-occipital fasciculus was found in both HS-TLE and MRI-neg TLE, suggesting a common lateralized effect of focal seizures. Both epilepsy groups had bilateral atrophy of the dorsal cingulum and corpus callosum fibers, which we interpret as a consequence of bilateral insults (potentially generalized seizures and/or medications). Underlying pathology, repeated focal seizures, and global insults each contribute to atrophy in specific tracts. Genetic factors make less of a contribution in this cohort. A multifactorial model of white matter atrophy in focal epilepsy is proposed. Ann Neurol 2017;81:240-250. © 2016 American Neurological Association.

  17. Quantification of structural changes in the corpus callosumin children with profound hypoxic-ischaemic brain injury

    Energy Technology Data Exchange (ETDEWEB)

    Stivaros, Stavros M. [Manchester Academic Health Science Centre, Academic Unit of Paediatric Radiology, Royal Manchester Children' s Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester (United Kingdom); University of Manchester, Centre for Imaging Sciences, Institute of Population Health, Manchester (United Kingdom); Radon, Mark R. [The Walton Centre NHS Foundation Trust, Department of Neuroradiology, Liverpool (United Kingdom); Mileva, Reneta; Gledson, Ann; Keane, John A. [University of Manchester, School of Computer Science, Manchester (United Kingdom); Connolly, Daniel J.A.; Batty, Ruth [Sheffield Children' s Hospital NHS Foundation Trust, Department of Neuroradiology, Sheffield (United Kingdom); Cowell, Patricia E. [University of Sheffield, Department of Human Communication Sciences, Sheffield (United Kingdom); Hoggard, Nigel; Griffiths, Paul D. [University of Sheffield, Academic Unit of Radiology, Sheffield (United Kingdom); Wright, Neville B.; Tang, Vivian [Manchester Academic Health Science Centre, Academic Unit of Paediatric Radiology, Royal Manchester Children' s Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester (United Kingdom)

    2016-01-15

    Birth-related acute profound hypoxic-ischaemic brain injury has specific patterns of damage including the paracentral lobules. To test the hypothesis that there is anatomically coherent regional volume loss of the corpus callosum as a result of this hemispheric abnormality. Study subjects included 13 children with proven acute profound hypoxic-ischaemic brain injury and 13 children with developmental delay but no brain abnormalities. A computerised system divided the corpus callosum into 100 segments, measuring each width. Principal component analysis grouped the widths into contiguous anatomical regions. We conducted analysis of variance of corpus callosum widths as well as support vector machine stratification into patient groups. There was statistically significant narrowing of the mid-posterior body and genu of the corpus callosum in children with hypoxic-ischaemic brain injury. Support vector machine analysis yielded over 95% accuracy in patient group stratification using the corpus callosum centile widths. Focal volume loss is seen in the corpus callosum of children with hypoxic-ischaemic brain injury secondary to loss of commissural fibres arising in the paracentral lobules. Support vector machine stratification into the hypoxic-ischaemic brain injury group or the control group on the basis of corpus callosum width is highly accurate and points towards rapid clinical translation of this technique as a potential biomarker of hypoxic-ischaemic brain injury. (orig.)

  18. Multiple sclerosis patients lacking oligoclonal bands in the cerebrospinal fluid have less global and regional brain atrophy.

    Science.gov (United States)

    Ferreira, Daniel; Voevodskaya, Olga; Imrell, Kerstin; Stawiarz, Leszek; Spulber, Gabriela; Wahlund, Lars-Olof; Hillert, Jan; Westman, Eric; Karrenbauer, Virginija Danylaité

    2014-09-15

    To investigate whether multiple sclerosis (MS) patients with and without cerebrospinal fluid (CSF) oligoclonal immunoglobulin G bands (OCB) differ in brain atrophy. Twenty-eight OCB-negative and thirty-five OCB-positive patients were included. Larger volumes of total CSF and white matter (WM) lesions; smaller gray matter (GM) volume in the basal ganglia, diencephalon, cerebellum, and hippocampus; and smaller WM volume in corpus callosum, periventricular-deep WM, brainstem, and cerebellum, were observed in OCB-positives. OCB-negative patients, known to differ genetically from OCB-positives, are characterized by less global and regional brain atrophy. This finding supports the notion that OCB-negative MS patients may represent a clinically relevant MS subgroup. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Eyebrow incision with supraorbital trephination for endoscopic corpus callosotomy: a feasibility study.

    Science.gov (United States)

    Tubbs, R Shane; Smyth, Matthew D; Salter, George; Doughty, Kyle; Blount, Jeffrey P

    2004-03-01

    We describe a novel technique for the partial bisection of the corpus callosum in order to increase the minimally invasiveness of this procedure. Brow incisions with midline trephinations were performed in six adult cadavers. An endoscope was next introduced and used to transect approximately the anterior two-thirds of the corpus callosum. No complications such as injury to the superior sagittal sinus or anterior cerebral artery were encountered in any of our cadaveric specimens. The corpus callosum was easily transected in each specimen. As a feasibility study, we believe this technique could provide a less invasive mechanism for patients who require corpus callosotomy and will minimize much of the morbidity associated with the traditional methods of sectioning the corpus callosum.

  20. Vaginal Atrophy

    Science.gov (United States)

    ... Body in Balance › Vaginal Atrophy Fact Sheet Vaginal Atrophy November, 2011 Download PDFs English Espanol Editors JoAnn ... MD Richard J. Santen, MD What is vaginal atrophy? Vaginal atrophy is a condition in which the ...

  1. Agenesis of the corpus callosumina premature infant associated with Langdon-Down syndrome

    Directory of Open Access Journals (Sweden)

    Velisavljev-Filipović Gordana

    2005-01-01

    Full Text Available Introduction Agenesis of the corpus callosum is an abnormality of the part of the brain connecting the two cerebral hemispheres. It can be partial, complete or atypical. The fibers from the cerebral cortex project towards the homotypical region of the contra-lateral cortex passing through the corpus callosum, and crossing the middle line. The absence of corpus callosum causes failure of information transfer from one hemisphere to the other. Children with this anomaly present with learning disabilities and trouble with memorizing facts. Agenesis of corpus callosum may be of syndromic or non-syndromic type. The more common form is the one not associated with any syndrome. The agenesis of corpus callosum is more frequent in male children. Case report This paper presents a child from a twin pregnancy with partial absence of corpus callosum. The pregnancy was not controlled. It ended in premature birth. The afflicted twin is a boy, second in birth order. Apart from agenesis of corpus callosum, he also suffers from Down syndrome. The first twin is healthy, with corpus callosum and with normal karyotype. There was no consanguinity. In the 6th month of pregnancy the mother suffered from infection of the upper respiratory tract that might be the etiological factor of this anomaly. The child was born with hypotrophy, and all anthropometric parameters were below the third percentile. In the neonatal period, the agenesis of corpus callosum was diagnosed by ultrasonic examination and confirmed by CT and MR examinations. The child is now three and a half month old. Active monitoring of the psychical and motor development will show whether there will be any retardation in the psycho-motor development and later deficiency of the higher cortical functions and intelligence. Discussion and Conclusion The clinical characteristics of this anomaly are numerous. They range from asymptomatic cases, with normal intellectual capacity, to severe mental retardation

  2. The effects of quetiapine on myelin morphology and expression of myelin basic protein in the corpus callosum of C57BL/6 mice with chronic alcohol exposure%喹硫平对慢性酒精暴露C57BL/6小鼠胼胝体髓鞘形态和髓鞘碱性蛋白表达的影响

    Institute of Scientific and Technical Information of China (English)

    刘蒙; 李新娟; 李爽; 张利彬; 韩金红; 赵营; 张瑞岭

    2015-01-01

    差异无统计学意义(t=2.081,P>0.05),喹硫平中、高剂量干预组(0.047±0.04、0.058±0.006)均高于酒精模型组(t=3.301、6.645,均P<0.05);喹硫平组(0.061±0.005)、喹硫平高剂量干预组与对照组相比差异均无统计学意义(t=0.041、1.137,均P>0.05).结论 慢性酒精暴露造成小鼠胼胝体白质髓鞘损伤,学习记忆能力下降;喹硫平中、高剂量干预可能会减轻或者防止慢性酒精使用引起的脑白质髓鞘损伤.%Objective To observe the effects of quetiapine on cognitive function,myelin morphology and expression of myelin basic protein in the corpus callosum of C57BL/6 mice with chronic alcohol exposure.Methods According to random number table,120 male C57BL/6 mice were divided into 6 groups,i.e.,control group,quetiapine control group (10 mg· kg-1· d-1quetiapine),alcohol group,5 mg· kg-1· d1quetiapine plus alcohol group,10 mg· kg-1· d-1 quetiapine plus alcohol group and 15 mg·kg-1· d-1quetiapine plus alcohol group,with 20 mice in each group.Mice in control group and quetiapine control group were maintained with water and solid diet for 20 weeks.Mice in alcohol group and quetiapine plus alcohol groups were maintained with water containing volume fraction of 10% alcohol and solid diet for 20 weeks.Drug with different doses was dissolved in mice drinking for intervention beginning at the 6th week and continuing to the end of the experiment.Morris water maze experiment was used to test the cognitive function.Luxol fast blue (LFB) staining and electron microscopy were used to observe morphology of corpus callosum.The expression of myelin basic protein in the corpus callosum was evaluated with immunofluorescence.Results (1)Morris water maze test showed that the cognition of mice in each group was different (F=4.702,P=0.002).The latency of mice in alcohol group ((22.8 ±5.5) s) was significantly longer compared with that of the control group((1 1.5± 7.1) s,t=3.546,P<0.05).The latency of 5 mg· kg1 · d-1and 10 mg· kg

  3. Vaginal Atrophy

    Science.gov (United States)

    Vaginal atrophy Overview Vaginal atrophy (atrophic vaginitis) is thinning, drying and inflammation of the vaginal walls due to your body having less estrogen. Vaginal atrophy occurs most often after ...

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

    Science.gov (United States)

    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…

  5. Positive correlations between corpus callosum thickness and intelligence.

    Science.gov (United States)

    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.

  6. 儿童伴胼胝体压部可逆性病变的轻度脑炎/脑病患者的临床特征分析%Clinical characteristics in four pediatric patients with mild encephalitis/encephalopathy with a reversible splenial lesion of corpus callosum

    Institute of Scientific and Technical Information of China (English)

    郝小生; 王江涛; 张艳凤; 梁建民

    2015-01-01

    目的 探讨儿童伴胼胝体压部可逆性病变的轻度脑炎/脑病(MERS)患者的临床及影像学特点.方法 对我院2013-2014年诊治的4例MERS患儿的临床资料进行回顾性分析,包括临床表现、神经系统异常体征、实验室检查、磁共振头部平扫(1.5 T)以及治疗和预后情况,并对相关文献进行复习.结果 4例患儿以消化道(3例)或呼吸道(1例)症状起病,以意识障碍(嗜睡3例、昏睡1例)、抽搐(4例)、头痛(1例)为主要症状,神经系统异常体征包括:颈项强直阳性(3例),双侧巴宾斯基征阳性(3例),双侧球结膜水肿(2例).实验室检查:血钠平均131.6 mmol/L,1例脑脊液常规生化异常.病原学检查:2例大便人轮状病毒抗原阳性,2例肺炎支原体抗体阳性.头颅MRI:仅见胼胝体压部可逆性异常信号(斑片状T1WI等或低信号,T2 WI稍高信号,FLAIR稍高信号,DWI高信号,表观弥散系数低信号,边界清晰).常规治疗基础上,加用地塞米松(4例)及丙种球蛋白(3例),1周内临床症状消失,2周内头颅MRI病灶消失.结论 MERS是一种临床-影像学综合征,常急性起病,临床症状轻微,头颅MRI有特征性改变,预后良好.%Objective To investigate the clinical and imaging features of mild encephalitis/encephalopathy with a reversible splenial lesion of corpus callosum (MERS) in children.Methods Four patients of MERS, who were diagnosed and treated in the First Hospital of Jilin University during 2013-2014, were collected retrospectively.Their clinical, laboratory, radiologic data and the related literatures were reviewed.Results Four patients onsetted as gastrointestinal symptom (3 cases) or respiratory (1 case) symptom, in accompany with disturbance of consciousness (3 cases of drowsiness, 1 case of lethargy), convulsions (4 cases), headache (1 case) as the main symptoms.Abnormal neurological signs included positive cervical resistance (3 cases), positive bilateral Babinski sign (3 cases), bilateral

  7. MK-801诱导的精神分裂症小鼠行为学和胼胝体髓鞘的改变%Behavioral alterations and demyelization of the corpus callosum in the mouse model of MK-801 induced schizophrenia

    Institute of Scientific and Technical Information of China (English)

    修芸; 张蕾; 仇玄; 陈林; 卢伟; 彭超; 程国华; 晁凤蕾; 唐勇

    2013-01-01

    Objective To explore the role of white matter injuries in the schizophrenia induced by the NMDA re-ceptor antagonist. Methods Adult male C57BL/6J mice (8 week old) were equally divided into four groups. One group was sub-chronically treated with saline solution, and the other three groups were intraperitoneally treated with MK-801 at dose of 0.025 mg/mL (M1), 0.050 mg/mL (M2) and 0.100 mg/mL (M3) in a volume 10 ml per kilogram body weight. All ani-mals were tested using Morris water maze at the 9th-15th day and using the Hole Board exploration as well as Rota Rod performance tests on the 16th day. The myelin basic protein (MBP) and the ultrastructure of the myelin sheaths in the cor-pus callosum were then examined using immunohistochemical methods, transmission electron microscope technique and stereological methods. Results The repeated sub-chronic MK-801 treatment did not induce impairment of spatial learning and memory in Morris water maze. The MK-801 treatment at 0.25 mg/kg and 1.00 mg/kg but not at 0.50 mg/kg resulted in less exploration to a new environment. The myelin staining with anti-MBP antibody was less intense in all three schizo-phrenic groups when compared to saline control group (P0.05),M1和M3组小鼠较对照组表现出对新环境探索减少的SZ阴性症状;大脑胼胝体区MBP染色M1组(179±10)%、M2组(235±7)%、M3组(152±9)%小鼠较对照组(288±18)%均降低(均P<0.01),其内有髓神经纤维髓鞘出现板层分离、节段性脱髓鞘等病变,M3组小鼠胼胝体内损伤有髓神经纤维比例高于对照组[(22.42±4.24)%vs.(3.84±1.35)%],差异有统计学意义(P<0.01)。结论胼胝体脱髓鞘改变可能是MK-801慢性给药诱导SZ的病因之一。

  8. Muscle atrophy

    Science.gov (United States)

    ... atrophy. Exercises may include ones done in a swimming pool to reduce the muscle workload, and other types ... a physical examination and ask about your medical history and symptoms, including: When did the muscle atrophy ...

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

    Science.gov (United States)

    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.

  10. Novel oligodendroglial alpha synuclein viral vector models of multiple system atrophy: studies in rodents and nonhuman primates.

    Science.gov (United States)

    Mandel, Ronald J; Marmion, David J; Kirik, Deniz; Chu, Yaping; Heindel, Clifford; McCown, Thomas; Gray, Steven J; Kordower, Jeffrey H

    2017-06-16

    Multiple system atrophy (MSA) is a horrible and unrelenting neurodegenerative disorder with an uncertain etiology and pathophysiology. MSA is a unique proteinopathy in which alpha-synuclein (α-syn) accumulates preferentially in oligodendroglia rather than neurons. Glial cytoplasmic inclusions (GCIs) of α-syn are thought to elicit changes in oligodendrocyte function, such as reduced neurotrophic support and demyelination, leading to neurodegeneration. To date, only a murine model using one of three promoters exist to study this disease. We sought to develop novel rat and nonhuman primate (NHP) models of MSA by overexpressing α-syn in oligodendroglia using a novel oligotrophic adeno-associated virus (AAV) vector, Olig001. To establish tropism, rats received intrastriatal injections of Olig001 expressing GFP. Histological analysis showed widespread expression of GFP throughout the striatum and corpus callosum with >95% of GFP+ cells co-localizing with oligodendroglia and little to no expression in neurons or astrocytes. We next tested the efficacy of this vector in rhesus macaques with intrastriatal injections of Olig001 expressing GFP. As in rats, we observed a large number of GFP+ cells in gray matter and white matter tracts of the striatum and the corpus callosum, with 90-94% of GFP+ cells co-localizing with an oligodendroglial marker. To evaluate the potential of our vector to elicit MSA-like pathology in NHPs, we injected rhesus macaques intrastriatally with Olig001 expressing the α-syn transgene. Histological analysis 3-months after injection demonstrated widespread α-syn expression throughout the striatum as determined by LB509 and phosphorylated serine-129 α-syn immunoreactivity, all of which displayed as tropism similar to that seen with GFP. As in MSA, Olig001-α-syn GCIs in our model were resistant to proteinase K digestion and caused microglial activation. Critically, demyelination was observed in the white matter tracts of the corpus callosum and

  11. Old Persian corpus [Dataset

    NARCIS (Netherlands)

    Bavant, M.

    2011-01-01

    XML Old Persian corpus. The corpus is based on publicly available data on the Web. Those data can be traced back to the grammar of Old Persian by Kent (1950). The corpus contains those data and is arranged in a way suitable for corpus searches.

  12. Corpus Linguistics Facilitates English Teaching

    Institute of Scientific and Technical Information of China (English)

    朱思亲

    2014-01-01

    Corpus linguistics has been widely applied in English teaching. Corpus linguistics has changed the way to teach English. The essay discusses two approaches in English teaching based on corpus, corpus-driven approach and corpus-based approach. It finds out that both corpus-driven approach and corpus-based approach facilitate English teaching in their own ways.

  13. Structural neuroimaging in preclinical dementia: From microstructural deficits and grey matter atrophy to macroscale connectomic changes.

    Science.gov (United States)

    Mak, Elijah; Gabel, Silvy; Mirette, Habib; Su, Li; Williams, Guy B; Waldman, Adam; Wells, Katie; Ritchie, Karen; Ritchie, Craig; O'Brien, John

    2017-05-01

    The last decade has witnessed a proliferation of neuroimaging studies characterising brain changes associated with Alzheimer's disease (AD), where both widespread atrophy and 'signature' brain regions have been implicated. In parallel, a prolonged latency period has been established in AD, with abnormal cerebral changes beginning many years before symptom onset. This raises the possibility of early therapeutic intervention, even before symptoms, when treatments could have the greatest effect on disease-course modification. Two important prerequisites of this endeavour are (1) accurate characterisation or risk stratification and (2) monitoring of progression using neuroimaging outcomes as a surrogate biomarker in those without symptoms but who will develop AD, here referred to as preclinical AD. Structural neuroimaging modalities have been used to identify brain changes related to risk factors for AD, such as familial genetic mutations, risk genes (for example apolipoprotein epsilon-4 allele), and/or family history. In this review, we summarise structural imaging findings in preclinical AD. Overall, the literature suggests early vulnerability in characteristic regions, such as the medial temporal lobe structures and the precuneus, as well as white matter tracts in the fornix, cingulum and corpus callosum. We conclude that while structural markers are promising, more research and validation studies are needed before future secondary prevention trials can adopt structural imaging biomarkers as either stratification or surrogate biomarkers. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Gastric atrophy, diagnosing and staging

    Institute of Scientific and Technical Information of China (English)

    Hala MT El-Zimaity

    2006-01-01

    H pylori is now accepted as the cause of gastritis and gastritis-associated diseases, such as duodenal ulcer,gastric ulcer, gastric carcinoma, and gastric MALT lymphoma. The natural history of H pylori gastritis includes inflammation progressing from the antrum into the adjacent corpus resulting in an atrophic front of advancing injury leading to a reduction in acid secretion and eventual loss of parietal cells and development of atrophy. Sub-typing intestinal metaplasia has no clinical value to the patient, the pathologist, or the endoscopist.The pattern, extent, and severity of atrophy, with or without intestinal metaplasia, is a far more important predictor than is intestinal metaplasia subtype. The challenge remains to identify a reliable marker that relates to pre-malignant potential.

  15. Callosal atrophy in mild cognitive impairment and Alzheimer's disease: different effects in different stages.

    Science.gov (United States)

    Di Paola, Margherita; Luders, Eileen; Di Iulio, Fulvia; Cherubini, Andrea; Passafiume, Domenico; Thompson, Paul M; Caltagirone, Carlo; Toga, Arthur W; Spalletta, Gianfranco

    2010-01-01

    Alzheimer's Disease (AD) is a neurodegenerative disorder that mainly affects grey matter (GM). Nevertheless, a number of investigations have documented white matter (WM) pathology associated with AD. The corpus callosum (CC) is the largest WM fiber bundle in the human brain. It has been shown to be susceptible to atrophy in AD mainly as a correlate of Wallerian degeneration of commissural nerve fibers of the neocortex. The aim of this study was to investigate which callosal regions are affected and whether callosal degeneration is associated with the stage of the disease. For this purpose, we analyzed high-resolution MRI data of patients with amnesic mild cognitive impairment (MCI) (n=20), mild AD (n=20), severe AD (n=10), and of healthy controls (n=20). Callosal morphology was investigated applying two different structural techniques: mesh-based geometrical modeling methods and whole-brain voxel-based analyses. Our findings indicate significant reductions in severe AD patients compared to healthy controls in anterior (genu and anterior body) and posterior (splenium) sections. In contrast, differences between healthy controls and mild AD patients or amnesic MCI patients were less pronounced and did not survive corrections for multiple comparisons. When correlating anterior and posterior WM density of the CC with GM density of the cortex in the severe AD group, we detected significant positive relationships between posterior sections of the CC and the cortex. We conclude that callosal atrophy is present predominantly in the latest stage of AD, where two mechanisms might contribute to WM alterations in severe AD: the Wallerian degeneration in posterior subregions and the myelin breakdown process in anterior subregions.

  16. CALBC silver standard corpus.

    Science.gov (United States)

    Rebholz-Schuhmann, Dietrich; Jimeno Yepes, Antonio José; Van Mulligen, Erik M; Kang, Ning; Kors, Jan; Milward, David; Corbett, Peter; Buyko, Ekaterina; Beisswanger, Elena; Hahn, Udo

    2010-02-01

    The CALBC initiative aims to provide a large-scale biomedical text corpus that contains semantic annotations for named entities of different kinds. The generation of this corpus requires that the annotations from different automatic annotation systems be harmonized. In the first phase, the annotation systems from five participants (EMBL-EBI, EMC Rotterdam, NLM, JULIE Lab Jena, and Linguamatics) were gathered. All annotations were delivered in a common annotation format that included concept identifiers in the boundary assignments and that enabled comparison and alignment of the results. During the harmonization phase, the results produced from those different systems were integrated in a single harmonized corpus ("silver standard" corpus) by applying a voting scheme. We give an overview of the processed data and the principles of harmonization--formal boundary reconciliation and semantic matching of named entities. Finally, all submissions of the participants were evaluated against that silver standard corpus. We found that species and disease annotations are better standardized amongst the partners than the annotations of genes and proteins. The raw corpus is now available for additional named entity annotations. Parts of it will be made available later on for a public challenge. We expect that we can improve corpus building activities both in terms of the numbers of named entity classes being covered, as well as the size of the corpus in terms of annotated documents.

  17. Learning about Spinal Muscular Atrophy

    Science.gov (United States)

    ... News Release Fischbeck Group Learning About Spinal Muscular Atrophy What is spinal muscular atrophy? What are the ... for Spinal Muscular Atrophy What is spinal muscular atrophy? Spinal muscular atrophy is a group of inherited ...

  18. IUS-LEX-CORPUS: CORPUS MYSTICUM

    Directory of Open Access Journals (Sweden)

    Riccardo Pozzo

    2014-01-01

    Full Text Available Sfruttando gli ingenti materiali a disposizione degli studiosi dal 1964 negli archivi, nelle banche dati, nei dizionari e nei lessici d'autore dell'ILIESI-CNR, il contributo considera una serie di momenti nella storia del pensiero, dalla politeía antica al cosmopolitismo moderno, che mettono in risalto le implicazioni filosofiche presenti nella polisemia del trinomio lex-ius-corpus.

  19. Corpus Design for Malay Corpus-based Speech Synthesis System

    Directory of Open Access Journals (Sweden)

    Tian-Swee Tan

    2009-01-01

    Full Text Available Problem statement: Speech corpus is one of the major components in corpus-based synthesis. The quality and coverage in speech corpus will affect the quality of synthesis speech sound. Approach: This study proposes a corpus design for Malay corpus-based speech synthesis system. This includes the study of design criteria in corpus-based speech synthesis, Malay corpus based database design and the concatenation engine in Malay corpus-based synthesis system. A set of 10 millions digital text corpuses for Malay language has been collected from Malay internet news. This text corpus had been analyzed using word frequency count to find out all high frequency words to be used for designing the sentences for speech corpus. Results: Altogether 381 sentences for speech corpus had been designed using 70% of high frequency words from 10 million text corpus. It consists of 16826 phoneme units and the total storage size is 37.6Mb. All the phone units are phonetically transcribed to preserve the phonetic context of its origin that will be used for phonetic context unit. This speech corpus had been labeled at phoneme level and used for variable length continuous phoneme based concatenation. Speech corpus is one of the major components in corpus-based synthesis. The quality and coverage in speech corpus will affect the quality of synthesized speech sound. Conclusion/Recommendation: This study has proposed a platform for designing speech corpus especially for Malay Text to Speech which can be further enhanced to support more coverage and higher naturalness of synthetic speech.

  20. Cortical and Subcortical Grey and White Matter Atrophy in Myotonic Dystrophies Type 1 and 2 Is Associated with Cognitive Impairment, Depression and Daytime Sleepiness

    Science.gov (United States)

    Prehn, Christian; Krogias, Christos; Schneider, Ruth; Klein, Jan; Gold, Ralf; Lukas, Carsten

    2015-01-01

    Objectives Central nervous system involvement is one important clinical aspect of myotonic dystrophy type 1 and 2 (DM1 and DM2). We assessed CNS involvement DM1 and DM2 by 3T MRI and correlated clinical and neuocognitive symptoms with brain volumetry and voxel-based morphometry (VBM). Methods 12 patients with juvenile or classical DM1 and 16 adult DM2 patients underwent 3T MRI, a thorough neurological and neuropsychological examination and scoring of depression and daytime sleepiness. Volumes of brain, ventricles, cerebellum, brainstem, cervical cord, lesion load and VBM results of the patient groups were compared to 33 matched healthy subjects. Results Clinical symptoms were depression (more pronounced in DM2), excessive daytime sleepiness (more pronounced in DM1), reduced attention and flexibility of thinking, and deficits of short-term memory and visuo-spatial abilities in both patient groups. Both groups showed ventricular enlargement and supratentorial GM and WM atrophy, with prevalence for more GM atrophy and involvement of the motor system in DM1 and more WM reduction and affection of limbic structures in DM2. White matter was reduced in DM1 in the splenium of the corpus callosum and in left-hemispheric WM adjacent to the pre- and post-central gyrus. In DM2, the bilateral cingulate gyrus and subgyral medio-frontal and primary somato-sensory WM was affected. Significant structural-functional correlations of morphological MRI findings (global volumetry and VBM) with clinical findings were found for reduced flexibility of thinking and atrophy of the left secondary visual cortex in DM1 and of distinct subcortical brain structures in DM2. In DM2, depression was associated with brainstem atrophy, Daytime sleepiness correlated with volume decrease in the middle cerebellar peduncles, pons/midbrain and the right medio-frontal cortex. Conclusion GM and WM atrophy was significant in DM1 and DM2. Specific functional-structural associations related morphological changes

  1. Spinal Muscular Atrophy (SMA)

    Science.gov (United States)

    ... Habits for TV, Video Games, and the Internet Spinal Muscular Atrophy (SMA) KidsHealth > For Parents > Spinal Muscular Atrophy (SMA) Print ... treatment for the disease's most troubling symptoms. About SMA Normally, healthy nerve cells in the brain called ...

  2. Optic nerve atrophy

    Science.gov (United States)

    Optic atrophy; Optic neuropathy ... There are many causes of optic atrophy. The most common is poor blood flow. This is called ischemic optic neuropathy. The problem most often affects older adults. The optic ...

  3. Multiple System Atrophy (MSA)

    Science.gov (United States)

    Diseases and Conditions Multiple system atrophy (MSA) By Mayo Clinic Staff Multiple system atrophy (MSA) is a rare neurological disorder that impairs your body's involuntary (autonomic) functions, including blood ...

  4. Spinal Muscular Atrophy (SMA)

    Science.gov (United States)

    ... Your 1- to 2-Year-Old Spinal Muscular Atrophy (SMA) KidsHealth > For Parents > Spinal Muscular Atrophy (SMA) A A A What's in this article? ... Outlook en español Atrofia muscular espinal Spinal muscular atrophy, or SMA, is an inherited condition that causes ...

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

    Science.gov (United States)

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

    Science.gov (United States)

    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...

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

    Science.gov (United States)

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

    2012-01-10

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

  8. Age effects in identifying and localising dichotic stimuli : A corpus callosum deficit?

    NARCIS (Netherlands)

    Gootjes, L; Van Strien, JW; Bouma, A; Bouma, J.M.

    2004-01-01

    In the present study, dichotic listening performance of 31 older adults was compared with performance of 25 younger adults under free and focussed attention conditions. In addition to an age-related general decrease in performance, we observed in the focussed attention condition increased asymmetry

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

    DEFF Research Database (Denmark)

    Plessen, Kerstin J; Grüner, Renate; Lundervold, Arvid

    2006-01-01

    interhemispheric fibers or reduced axonal myelination. FA values did not correlate significantly with the severity of tic symptoms. Group differences in measures of connectivity did not seem to be attributable to the presence of comorbid ADHD or OCD, to medication exposure, or group differences in IQ. CONCLUSION...

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

    Science.gov (United States)

    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...

  11. Instrument specific use-dependent plasticity shapes the anatomical properties of the corpus callosum

    DEFF Research Database (Denmark)

    Vollmann, Henning; Ragert, Patrick; Conde, Virginia;

    2014-01-01

    , the amount of IHI in pianists was comparable to that of non-musicians and there was no significant structure-function relationship. Our findings indicate instrument specific use-dependent plasticity in both functional (IHI) and structural (FA) connectivity of motor related brain regions in musicians....

  12. Corpus Annotation for Parser Evaluation

    OpenAIRE

    CARROLL, JOHN; Minnen, Guido; Briscoe, Ted

    1999-01-01

    We describe a recently developed corpus annotation scheme for evaluating parsers that avoids shortcomings of current methods. The scheme encodes grammatical relations between heads and dependents, and has been used to mark up a new public-domain corpus of naturally occurring English text. We show how the corpus can be used to evaluate the accuracy of a robust parser, and relate the corpus to extant resources.

  13. Language Planning: Corpus Planning.

    Science.gov (United States)

    Baldauf, Richard B., Jr.

    1989-01-01

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

  14. Tagging the Teleman Corpus

    CERN Document Server

    Brants, T; Brants, Thorsten; Samuelsson, Christer

    1995-01-01

    Experiments were carried out comparing the Swedish Teleman and the English Susanne corpora using an HMM-based and a novel reductionistic statistical part-of-speech tagger. They indicate that tagging the Teleman corpus is the more difficult task, and that the performance of the two different taggers is comparable.

  15. A Rare Case of Pericallosal Lipoma Associated with Bilaterally Symmetrical Lateral Ventricular Choroid Plexus Lipomas without Corpus Callosal Anomalies

    Directory of Open Access Journals (Sweden)

    Parag Suresh Mahajan

    2013-01-01

    Full Text Available Lipomas constitute less than 5% of primary brain tumors. Pericallosal lipomas (PCLp constitute almost half of all intracranial lipomas. Corpus callosal anomalies commonly occur in cases with PCLps. Although PCLp is often described as corpus callosal lipoma, it is most often pericallosal in location. PCLps may have calcification in the periphery and may continue into lateral ventricles, which is a very rare presentation. We observed a case of PCLp with peripheral calcifications associated with PCLp continuing as bilaterally symmetrical lateral ventricular choroid plexus lipomas (CPLp without any corpus callosal or other central nervous system anomalies, and as this is not been previously reported, we are presenting it. The appearance of PCLp in this case does not correspond to the descriptions of any of the existing morphological types (anterior and posterior of classification of PCLps; it is rather mixed, where PCLp occupies both anterior and posterior locations around the corpus callosum.

  16. Explorations of Corpus Translation Studies

    Institute of Scientific and Technical Information of China (English)

    何琳琳

    2014-01-01

    Corpus-based translation studies belong to a new translation study paradigm which rose at the beginning of 1990s. The rise of corpus brings the update of research tools and research methods, and lead to the emerging of Corpus Translation Stud-ies. It is necessary to introduce the theory basis of Translational English Corpus and its application in the translation, especially in the science and technology translation. Besides, it makes an analysis and discussion about the potential of Corpus Translation Stud-ies.

  17. Optic atrophy and cerebral infarcts caused by methanol intoxication: MRI

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, H.H. [Dept. of Diagnostic Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei (Taiwan, Province of China); Chen, C.Y. [Dept. of Diagnostic Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei (Taiwan, Province of China); Chen, F.H. [Dept. of Diagnostic Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei (Taiwan, Province of China); Lee, C.C. [Dept. of Diagnostic Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei (Taiwan, Province of China); Chou, T.Y. [Dept. of Diagnostic Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei (Taiwan, Province of China); Zimmerman, R.A. [Children`s Hospital of Philadelphia, PA (United States). Dept. of Radiology

    1997-03-01

    We present the MRI findings of cerebral and optic pathway damage in the acute and subacute stages of methanol intoxication. In the acute stage, CT and MRI showed bilateral haemorrhagic necrosis of the corpus striatum and infarcts in the anterior and middle cerebral arterial territories. MRI in the subacute stage demonstrated atrophy of the optic chiasm and prechiasmatic optic nerves in addition to the cerebral infarcts. The patient survived, with total blindness. (orig.)

  18. Individual Assessment of Brain Tissue Changes in MS and the Effect of Focal Lesions on Short-Term Focal Atrophy Development in MS: A Voxel-Guided Morphometry Study

    Science.gov (United States)

    Fox, Jan; Kraemer, Matthias; Schormann, Thorsten; Dabringhaus, Andreas; Hirsch, Jochen; Eisele, Philipp; Szabo, Kristina; Weiss, Christel; Amann, Michael; Weier, Katrin; Naegelin, Yvonne; Kappos, Ludwig; Gass, Achim

    2016-01-01

    We performed voxel-guided morphometry (VGM) investigating the mechanisms of brain atrophy in multiple sclerosis (MS) related to focal lesions. VGM maps detect regional brain changes when comparing 2 time points on high resolution T1-weighted (T1w) magnetic resonace imaging (MRI). Two T1w MR datasets from 92 relapsing-remitting MS patients obtained 12 months apart were analysed with VGM. New lesions and volume changes of focal MS lesions as well as in the surrounding tissue were identified by visual inspection on colour coded VGM maps. Lesions were dichotomized in active and inactive lesions. Active lesions, defined by either new lesions (NL) (volume increase > 5% in VGM), chronic enlarging lesions (CEL) (pre-existent T1w lesions with volume increase > 5%), or chronic shrinking lesions (CSL) (pre-existent T1w lesions with volume reduction > 5%) in VGM, were accompanied by tissue shrinkage in surrounding and/or functionally related regions. Volume loss within the corpus callosum was highly correlated with the number of lesions in its close proximity. Volume loss in the lateral geniculate nucleus was correlated with lesions along the optic radiation. VGM analysis provides strong evidence that all active lesion types (NL, CEL, and CSL) contribute to brain volume reduction in the vicinity of lesions and/or in anatomically and functionally related areas of the brain. PMID:27043553

  19. Individual Assessment of Brain Tissue Changes in MS and the Effect of Focal Lesions on Short-Term Focal Atrophy Development in MS: A Voxel-Guided Morphometry Study

    Directory of Open Access Journals (Sweden)

    Jan Fox

    2016-04-01

    Full Text Available We performed voxel-guided morphometry (VGM investigating the mechanisms of brain atrophy in multiple sclerosis (MS related to focal lesions. VGM maps detect regional brain changes when comparing 2 time points on high resolution T1-weighted (T1w magnetic resonace imaging (MRI. Two T1w MR datasets from 92 relapsing-remitting MS patients obtained 12 months apart were analysed with VGM. New lesions and volume changes of focal MS lesions as well as in the surrounding tissue were identified by visual inspection on colour coded VGM maps. Lesions were dichotomized in active and inactive lesions. Active lesions, defined by either new lesions (NL (volume increase > 5% in VGM, chronic enlarging lesions (CEL (pre-existent T1w lesions with volume increase > 5%, or chronic shrinking lesions (CSL (pre-existent T1w lesions with volume reduction > 5% in VGM, were accompanied by tissue shrinkage in surrounding and/or functionally related regions. Volume loss within the corpus callosum was highly correlated with the number of lesions in its close proximity. Volume loss in the lateral geniculate nucleus was correlated with lesions along the optic radiation. VGM analysis provides strong evidence that all active lesion types (NL, CEL, and CSL contribute to brain volume reduction in the vicinity of lesions and/or in anatomically and functionally related areas of the brain.

  20. Du corpus au dictionnaire

    CERN Document Server

    Jacquemin, Bernard

    2009-01-01

    In this article, we propose an automatic process to build multi-lingual lexico-semantic resources. The goal of these resources is to browse semantically textual information contained in texts of different languages. This method uses a mathematical model called Atlas s\\'emantiques in order to represent the different senses of each word. It uses the linguistic relations between words to create graphs that are projected into a semantic space. These projections constitute semantic maps that denote the sense trends of each given word. This model is fed with syntactic relations between words extracted from a corpus. Therefore, the lexico-semantic resource produced describes all the words and all their meanings observed in the corpus. The sense trends are expressed by syntactic contexts, typical for a given meaning. The link between each sense trend and the utterances used to build the sense trend are also stored in an index. Thus all the instances of a word in a particular sense are linked and can be browsed easily...

  1. Towards an integrated corpus stylistics

    Directory of Open Access Journals (Sweden)

    McIntyre Dan

    2015-12-01

    Full Text Available Over recent years, the use of corpora in stylistic analysis has grown in popularity. However, questions still remain over the remit of corpus stylistics, its distinction from corpus linguistics generally and its capacity to explain complex stylistic effects. This article argues in favour of an integrated corpus stylistics; that is, an approach to corpus stylistics that integrates it with other stylistic methods and analytical frameworks. I suggest that this approach is needed for two main reasons: (i it is analytically necessary in order to fully explain stylistic effects in texts, and (ii integrating corpus methods with other stylistic tools is what will distinguish corpus stylistics from corpus linguistics. My argument is supported by reference to examples from Mark Haddon’s no vel The Curious Incident of the Dog in the Night-time and the HBO TV series Deadwood. Both these examples rely for their explanation on a combination of corpus stylistic analytical techniques and other stylistic methods of analysis.

  2. [Corpus Hermeticum in history].

    Science.gov (United States)

    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

  3. Corpus vitreum, retina og chorioidea biopsi

    DEFF Research Database (Denmark)

    Scherfig, Erik Christian Høegh

    2002-01-01

    oftalmology, biopsy, choroid, corpus vitreum, retina, malignant melanoma, biopsy technic, retinoblastoma......oftalmology, biopsy, choroid, corpus vitreum, retina, malignant melanoma, biopsy technic, retinoblastoma...

  4. Progressive hemifacial atrophy

    Directory of Open Access Journals (Sweden)

    Abhijeet Sande

    2013-01-01

    Full Text Available Progressive hemifacial atrophy, also known as Parry-Romberg Syndrome, is an uncommon degenerative and poorly understood condition. It is characterized by a slow and progressive but self-limited atrophy affecting one side of the face. The incidence and the cause of this alteration are unknown. A cerebral disturbance of fat metabolism has been proposed as a primary cause. Possible factors that are involved in the pathogenesis include trauma, viral infections, heredity, endocrine disturbances and auto-immunity. The most common complications that appear in association to this disorder are: trigeminal neuralgia, facial paresthesia, severe headache and epilepsy. Characteristically, the atrophy progresses slowly for several years and, it becomes stable. The objective of this work is, through the presentation of a clinical case, to accomplish a literature review concerning general characteristics, etiology, physiopathology and treatment of progressive hemifacial atrophy.

  5. Spinal muscular atrophy

    National Research Council Canada - National Science Library

    D'Amico, Adele; Mercuri, Eugenio; Tiziano, Francesco D; Bertini, Enrico

    2011-01-01

    Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease characterized by degeneration of alpha motor neurons in the spinal cord, resulting in progressive proximal muscle weakness and paralysis...

  6. Spinal Muscular Atrophy

    Science.gov (United States)

    Spinal muscular atrophy (SMA) is a genetic disease that attacks nerve cells, called motor neurons, in the spinal cord. These cells communicate with your voluntary muscles - the ones you can control, like in your ...

  7. Universum Inference and Corpus Homogeneity

    Science.gov (United States)

    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.

  8. Bed Rest Muscular Atrophy

    Science.gov (United States)

    Greenleaf, John E.

    2000-01-01

    A major debilitating response from prolonged bed rest (BR) is muscle atrophy, defined as a "decrease in size of a part of tissue after full development has been attained: a wasting away of tissue as from disuse, old age, injury or disease". Part of the complicated mechanism for the dizziness, increased body instability, and exaggerated gait in patients who arise immediately after BR may be a result of not only foot pain, but also of muscular atrophy and associated reduction in lower limb strength. Also, there seems to be a close association between muscle atrophy and bone atrophy. A discussion of many facets of the total BR homeostatic syndrome has been published. The old adage that use determines form which promotes function of bone (Wolff's law) also applies to those people exposed to prolonged BR (without exercise training) in whom muscle atrophy is a consistent finding. An extreme case involved a 16-year-old boy who was ordered to bed by his mother in 1932: after 50 years in bed he had "a lily-white frame with limbs as thin as the legs of a ladder-back chair". These findings emphasize the close relationship between muscle atrophy and bone atrophy. In addition to loss of muscle mass during deconditioning, there is a significant loss of muscle strength and a decrease in protein synthesis. Because the decreases in force (strength) are proportionately greater than those in fiber size or muscle cross-sectional area, other contributory factors must be involved; muscle fiber dehydration may be important.

  9. Bed Rest Muscular Atrophy

    Science.gov (United States)

    Greenleaf, John E.

    2000-01-01

    A major debilitating response from prolonged bed rest (BR) is muscle atrophy, defined as a "decrease in size of a part of tissue after full development has been attained: a wasting away of tissue as from disuse, old age, injury or disease". Part of the complicated mechanism for the dizziness, increased body instability, and exaggerated gait in patients who arise immediately after BR may be a result of not only foot pain, but also of muscular atrophy and associated reduction in lower limb strength. Also, there seems to be a close association between muscle atrophy and bone atrophy. A discussion of many facets of the total BR homeostatic syndrome has been published. The old adage that use determines form which promotes function of bone (Wolff's law) also applies to those people exposed to prolonged BR (without exercise training) in whom muscle atrophy is a consistent finding. An extreme case involved a 16-year-old boy who was ordered to bed by his mother in 1932: after 50 years in bed he had "a lily-white frame with limbs as thin as the legs of a ladder-back chair". These findings emphasize the close relationship between muscle atrophy and bone atrophy. In addition to loss of muscle mass during deconditioning, there is a significant loss of muscle strength and a decrease in protein synthesis. Because the decreases in force (strength) are proportionately greater than those in fiber size or muscle cross-sectional area, other contributory factors must be involved; muscle fiber dehydration may be important.

  10. Orfismo en el Corpus Philostrateum

    Directory of Open Access Journals (Sweden)

    Susana M. Lizcano Rejano

    2003-06-01

    Full Text Available We search through the Corpus Philostrateum for the presence of connections between this literary production and Orphismus – its system of beliefs, its peculiar interpretation of the traditional Greek mythology, its proposal for a particular way of life. Also, we try to determine the relation, that we can find in this corpus between the ideology and customs that the Pythagoreans and Orphics supported.

  11. The Bulgarian National Corpus: Theory and Practice in Corpus Design

    Directory of Open Access Journals (Sweden)

    Svetla Koeva

    2012-12-01

    Full Text Available The paper discusses several key concepts related to the development of corpora and reconsiders them in light of recent developments in NLP. On the basis of an overview of present-day corpora, we conclude that the dominant practices of corpus design do not utilise adequately the technologies and, as a result, fail to meet the demands of corpus linguistics, computational lexicology and computational linguistics alike.We proceed to lay out a data-driven approach to corpus design, which integrates the best practices of traditional corpus linguistics with the potential of the latest technologies allowing fast collection, automatic metadata description and annotation of large amounts of data. Thus, the gist of the approach we propose is that corpus design should be centred on amassing large amounts of mono- and multilingual texts and on providing them with a detailed metadata description and high-quality multi-level annotation.We go on to illustrate this concept with a description of the compilation, structuring, documentation, and annotation of the Bulgarian National Corpus (BulNC. At present it consists of a Bulgarian part of 979.6 million words, constituting the corpus kernel, and 33 Bulgarian-X language corpora, totalling 972.3 million words, 1.95 billion words altogether. The BulNC is supplied with a comprehensive metadata description, which allows us to organise the texts according to different principles. The Bulgarian part of the BulNC is automatically processed (tokenised and sentence split and  annotated at several levels: morphosyntactic tagging, lemmatisation, word-sense annotation, annotation of noun phrases and named entities. Some levels of annotation are also applied to the Bulgarian-English parallel corpus with the prospect of expanding multilingual annotation both in terms of linguistic levels and the number of languages for which it is available. We conclude with a brief evaluation of the quality of the corpus and an outline of

  12. Research opportunities in muscle atrophy

    Science.gov (United States)

    Herbison, G. J. (Editor); Talbot, J. M. (Editor)

    1984-01-01

    Muscle atrophy in a weightless environment is studied. Topics of investigation include physiological factors of muscle atrophy in space flight, biochemistry, countermeasures, modelling of atrophied muscle tissue, and various methods of measurement of muscle strength and endurance. A review of the current literature and suggestions for future research are included.

  13. Dominant optic atrophy

    DEFF Research Database (Denmark)

    Lenaers, Guy; Hamel, Christian; Delettre, Cécile

    2012-01-01

    DEFINITION OF THE DISEASE: Dominant Optic Atrophy (DOA) is a neuro-ophthalmic condition characterized by a bilateral degeneration of the optic nerves, causing insidious visual loss, typically starting during the first decade of life. The disease affects primary the retinal ganglion cells (RGC...

  14. 2001-2011

    DEFF Research Database (Denmark)

    Poggesi, Anna; Pantoni, Leonardo; Inzitari, Domenico;

    2011-01-01

    atrophy, and corpus callosum morphology). The LADIS study provides a good example of harmonization of instruments (MRI protocol, clinical, neuropsychological, and functional scales) within an international collaboration. Currently, the LADIS study is providing data about the natural history of WMC...

  15. Helicobacter pyloriin gastric corpus of patients 20 years after partial gastric resection

    Institute of Scientific and Technical Information of China (English)

    Christian Kirsch; Ahmed Madisch; Petja Piehler; Ekkehard Bayerd(o)rffer; Manfred Stolte; Stephan Miehlke

    2004-01-01

    AIM: To determine the long-term prevalence of Helicobacter pylori (H pylori) gastritis in patients after partial gastric resection due to peptic ulcer, and to compare the severity of H pylori-positive gastritis in the corpus mucosa between partial gastrectomy patients and matched controls.METHODS: Endoscopic biopsies were obtained from 57 patients after partial gastric resection for histological examination using hematoxylin/eosin and Warthin-Starry staining. Gastritis was graded according to the updated Sydney system. Severity of corpus gastritis was compared between H pylori-positive partial gastrectomy patients and H pylori-positive duodenal ulcer patients matched for age and gender.RESULTS: In partial gastrectomy patients, surgery was performed 20 years (median) prior to evaluation. In 25 patients (43.8%) H pylori was detected histologically in the gastric remnant. Gastric atrophy was more common in H pylori-positive compared to H pylori-negative partial gastrectomy patients (P<0.05). The severity of corpus gastritis was significantly lower in H pylori-positive partial gastrectomy patients compared to duodenal ulcer patients (P<0.01). There were no significant differences in the activity of gastritis, atrophy and intestinal metaplasia between the two groups.CONCLUSION: The long-term prevalence of H pylorigastritis in the gastric corpus of patients who underwent partial gastric resection due to peptic ulcer disease is comparable to the general population. The expression of H pylori gastritis in the gastric remnant does not resemble the gastric cancer phenotype.

  16. DEVELOPING SOFTWARE FOR CORPUS RESEARCH

    Directory of Open Access Journals (Sweden)

    Oliver Mason

    2008-06-01

    Full Text Available 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 software is available. Apart from software itself, data formats are also of great importance for text processing. But again, many practitioners are not very aware of the options available to them, and thus idiosyncratic text formats often make sharing of resources difficult if not impossible. This article discusses some issues relating to both data and processing which should aid researchers to become more aware of the choices available to them when it comes to using computers in linguistic research. It also describes an easy way towards automating some common text processing tasks that can easily be acquired without knowledge of actual computer programming.

  17. Normative Data of Corpus Callosal Morphology in a North-West Indian Population- An autopsy and MRI study

    Directory of Open Access Journals (Sweden)

    Tulika Gupta

    2009-01-01

    The values of different CC parameters observed were almost similar to the values reported in the other two Indian studies. However, Indian values were found to be more than the Japanese values for length, height and most of the widths of CC. The length and width of CC were found to be less than those of Caucasian population. Generation of this data will help in comparing the CC structure of different sex and ages, to study variations from the normal and may help in surgical planning. Keywords:autopsy brains; corpus callosum; magnetic resonance imaging; morphometric data.

  18. Lancaster Summer School in Corpus Linguistics

    Directory of Open Access Journals (Sweden)

    Jaka Čibej

    2016-11-01

    Full Text Available Med 12. in 15. julijem je na Univerzi v Lancastru potekala poletna šola korpusnega jezikoslovja Lancaster Summer Schools in Corpus Linguistics and Other Digital Methods. Poletno šolo so organizirali UCREL (University Centre for Computer Corpus Research on Language, ERC (Evropski svet za raziskave – European Research Council, CASS (ESRC Centre for Corpus Approaches to Social Science in ESRC (Economic and Social Research Council, razdeljena pa je bila na šest programov, prilagojenih različnim področjem: Korpusno jezikoslovje za proučevanje jezikov (Corpus Linguistics for Language Studies, Korpusno jezikoslovje za družbene vede (Corpus Linguistics for Social Science, Korpusno jezikoslovje za humanistiko (Corpus Linguistics for Humanities, Statistika za korpusno jezikoslovje (Statistics for Corpus Linguistics, Geografski informacijski sistemi za digitalno humanistiko (Geographical Information Systems for the Digital Humanities in Korpusno podprta obdelava naravnih jezikov (Corpus-based Natural Language Processing.

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

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Corpus Christi Ship Channel, Corpus Christi, TX, safety zone. 165.808 Section 165.808 Navigation and Navigable Waters COAST GUARD... § 165.808 Corpus Christi Ship Channel, Corpus Christi, TX, safety zone. (a) The following areas...

  20. [Posterior cortical atrophy].

    Science.gov (United States)

    Solyga, Volker Moræus; Western, Elin; Solheim, Hanne; Hassel, Bjørnar; Kerty, Emilia

    2015-06-02

    Posterior cortical atrophy is a neurodegenerative condition with atrophy of posterior parts of the cerebral cortex, including the visual cortex and parts of the parietal and temporal cortices. It presents early, in the 50s or 60s, with nonspecific visual disturbances that are often misinterpreted as ophthalmological, which can delay the diagnosis. The purpose of this article is to present current knowledge about symptoms, diagnostics and treatment of this condition. The review is based on a selection of relevant articles in PubMed and on the authors' own experience with the patient group. Posterior cortical atrophy causes gradually increasing impairment in reading, distance judgement, and the ability to perceive complex images. Examination of higher visual functions, neuropsychological testing, and neuroimaging contribute to diagnosis. In the early stages, patients do not have problems with memory or insight, but cognitive impairment and dementia can develop. It is unclear whether the condition is a variant of Alzheimer's disease, or whether it is a separate disease entity. There is no established treatment, but practical measures such as the aid of social care workers, telephones with large keypads, computers with voice recognition software and audiobooks can be useful. Currently available treatment has very limited effect on the disease itself. Nevertheless it is important to identify and diagnose the condition in its early stages in order to be able to offer patients practical assistance in their daily lives.

  1. A Possible Link between Gastric Mucosal Atrophy and Gastric Cancer after Helicobacter pylori Eradication

    Science.gov (United States)

    Tahara, Tomomitsu; Shibata, Tomoyuki; Horiguchi, Noriyuki; Kawamura, Tomohiko; Okubo, Masaaki; Ishizuka, Takamitsu; Nagasaka, Mitsuo; Nakagawa, Yoshihito; Ohmiya, Naoki

    2016-01-01

    Background The effect of H. pylori eradication in gastric cancer prevention can be attributed to the improvement of atrophic gastritis, which is a known risk of gastric cancer. However, gastric cancer has also been diagnosed after long-term H. pylori eradication. This study aimed to clarify the association between gastric atrophy and gastric cancer after H. pylori eradication, including its clinicopathological features. Methods A total of 55 consecutive patients with 64 early gastric cancers (EGCs) diagnosed after H. pylori eradication were enrolled. The degree of endoscopic atrophy and the histological degrees of mononuclear cell infiltration, atrophy, and metaplasia in the corpus and adjacent mucosa of the EGCs were determined and scored. Results The majority of EGCs (63/64) were located within the endoscopically assessed atrophic mucosa or along the atrophic border. The adjacent mucosa of the EGCs presented significantly higher degrees of all histological parameters than in the corpus (mononuclear cell infiltration, 0.86+/-0.09 vs. 0.51+/-0.11, P = 0.016; atrophy, 1.77+/-0.13 vs. 0.65+/-0.14, Pgastric ulcers. Conclusions Severe gastric atrophy remained in the adjacent mucosa of the EGCs after H. pylori eradication, which may be linked to gastric carcinogenesis. PMID:27706195

  2. 32 CFR 516.20 - Habeas Corpus.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Habeas Corpus. 516.20 Section 516.20 National... RELATIONS LITIGATION Reporting Legal Proceedings to HQDA § 516.20 Habeas Corpus. (a) General. A soldier may file a writ of habeas corpus to challenge his continued custody (usually in a post...

  3. Progressive hemifacial atrophy with ciliary body atrophy and ocular hypotony

    Directory of Open Access Journals (Sweden)

    T Ashwini Kini

    2015-01-01

    Full Text Available Progressive hemifacial atrophy (PHA is a disease of unknown etiology affecting one-half of the face. Ocular involvement is uncommon. Atrophy of iris is rare, with only a few cases of partial atrophy being reported in the literature. We report a case of total atrophy of iris and ciliary body with associated ocular hypotony in a 16-year-old girl with PHA. We believe this is the first reported case of complete atrophy of iris and ciliary body in PHA. Ocular hypotony in PHA was thought to be due to intra-ocular inflammation. However in our case it appears to be secondary to severe atrophy of the ciliary body.

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

    Science.gov (United States)

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

    2014-01-01

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

  5. Muscular atrophy in diabetic neuropathy

    DEFF Research Database (Denmark)

    Andersen, H; Gadeberg, P C; Brock, B

    1997-01-01

    Diabetic patients with polyneuropathy develop motor dysfunction. To establish whether motor dysfunction is associated with muscular atrophy the ankle dorsal and plantar flexors of the non-dominant leg were evaluated with magnetic resonance imaging in 8 patients with symptomatic neuropathy, in 8 non...... confirmed that the atrophy predominated distally. We conclude that muscular atrophy underlies motor weakness at the ankle in diabetic patients with polyneuropathy and that the atrophy is most pronounced in distal muscles of the lower leg indicating that a length dependent neuropathic process explains...

  6. Adults with attention-deficit/hyperactivity disorder - A diffusion-tensor imaging study of the corpus callosum

    DEFF Research Database (Denmark)

    Dramsdahl, Margaretha; Westerhausen, René; Haavik, Jan;

    2012-01-01

    to the control group, whereas the size of the CC did not differ across groups. Our findings thus demonstrate a divergence between microstructural and macrostructural measures in the CC of adults with ADHD. This contrasts with findings in children demonstrating callosal abnormalities in both microstructure...... and macrostructure. Our results may indicate that adults with ADHD in part have succeeded in passing by an earlier developmental delay of the CC, resulting in a normalization of callosal macrostructure into adulthood. However, microstructural differences are still present in adults, which may point to an abnormal...... lateralization in adults with ADHD, or could be a sign of a persisting impairment....

  7. Selectively Reduced Posterior Corpus Callosum Size in a Population-Based Sample of Young Adults Born with Low Birth Weight

    DEFF Research Database (Denmark)

    Aukland, S M; Westerhausen, R; Plessen, K J

    2011-01-01

    BACKGROUND AND PURPOSE: Several studies suggest that VLBW is associated with a reduced CC size later in life. We aimed to clarify this in a prospective, controlled study of 19-year-olds, hypothesizing that those with LBWs had smaller subregions of CC than the age-matched controls, even after...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

  10. Application of fused lasso logistic regression to the study of corpus callosum thickness in early Alzheimer's disease.

    Science.gov (United States)

    Lee, Sang H; Yu, Donghyeon; Bachman, Alvin H; Lim, Johan; Ardekani, Babak A

    2014-01-15

    We propose a fused lasso logistic regression to analyze callosal thickness profiles. The fused lasso regression imposes penalties on both the l1-norm of the model coefficients and their successive differences, and finds only a small number of non-zero coefficients which are locally constant. An iterative method of solving logistic regression with fused lasso regularization is proposed to make this a practical procedure. In this study we analyzed callosal thickness profiles sampled at 100 equal intervals between the rostrum and the splenium. The method was applied to corpora callosa of elderly normal controls (NCs) and patients with very mild or mild Alzheimer's disease (AD) from the Open Access Series of Imaging Studies (OASIS) database. We found specific locations in the genu and splenium of AD patients that are proportionally thinner than those of NCs. Callosal thickness in these regions combined with the Mini Mental State Examination scores differentiated AD from NC with 84% accuracy.

  11. Oligodendrocytes in Mouse Corpus Callosum are Coupled Via Gap Junction Channels Formedby Connexin47 and Connexin32

    Institute of Scientific and Technical Information of China (English)

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

    2010-01-01

    已有的超微结构研究显示,白质中的少突胶质细胞和星形胶质细胞之间存在缝隙连接,但少突胶质细胞之间不存在缝隙连接,虽然体外培养的少突胶质细胞可形成功能性缝隙连接.本文研究新生小鼠胼胝体急性脑片中的少突胶质细胞的功能性连接.以全细胞膜片钳技术用生物胞素(一种可渗透的缝隙连接示踪剂)标记少突胶质细胞.平均61个细胞为链霉亲和素-Cy3标记的生物胞素阳性.约77%的连结细胞表达少突胶质细胞标志蛋白CNPase阳性染色,9%表达星形胶质细胞标志蛋白GFAP阳性,14%为CNPase和GFAP阴性.后者的大部分表达Olig2和一些NG2(少突胶质细胞前体细胞的标志物).少突胶质细胞表达Cx47、Cx32和Cx29,星形胶质细胞表达Cx43和Cx30.在Cx47敲除小鼠中,连结细胞的数量减少80%.单独删除Cx32或Cx29并不能显著减少连结细胞的数量,但Cx32/Cx47双缺陷小鼠中没有观察到相互连结的细胞.Cx47敲除完全消除了少突胶质细胞与星形胶质细胞间的耦联.在Cx43敲除动物中,少突胶质细胞-星形胶质细胞间连接仍然存在,但与少突胶质细胞前体细胞间的耦联没有被观察到.在Cx43/Cx30双敲除小鼠中,少突胶质细胞-星形胶质细胞连接几乎不存在.解开连结的少突胶质细胞显示为较高的膜输入电阻.本文认为,白质中的少突胶质细胞依靠Cx47和Cx32的表达形成功能性的合胞体,而星形胶质蛋白缝隙连接蛋白的表达能提升此网络的大小.

  12. Sept approches à un corpus

    DEFF Research Database (Denmark)

    La linguistique moderne permet d'analyser la langue parlée dans sa spécificité discursive et situationnelle, syntaxique et lexicale, lui accordant ainsi un statut égal à celui de l'écrit. Le choix de présenter sept approches différentes à un même corpus de base donne lieu d'un côté à une analyse...

  13. Genetics Home Reference: multiple system atrophy

    Science.gov (United States)

    ... Home Health Conditions multiple system atrophy multiple system atrophy Enable Javascript to view the expand/collapse boxes. ... PDF Open All Close All Description Multiple system atrophy is a progressive brain disorder that affects movement ...

  14. The inheritance of peripapillary atrophy

    NARCIS (Netherlands)

    Healey, Paul R.; Mitchell, Paul; Gilbert, Clare E.; Lee, Anne J.; Ge, Dongliang; Snieder, Harold; Spector, Timothy D.; Hammond, Christopher J.

    2007-01-01

    PURPOSE. To estimate the relative importance of genes and environment in peripapillary atrophy type beta (beta-PPA) in a classic twin study. METHODS. Female twin pairs (n = 506) aged 49 to 79 years were recruited from the St. Thomas' UK Adult Twin Registry. Peripapillary atrophy was identified from

  15. Dominant optic atrophy

    Directory of Open Access Journals (Sweden)

    Lenaers Guy

    2012-07-01

    Full Text Available Abstract Definition of the disease Dominant Optic Atrophy (DOA is a neuro-ophthalmic condition characterized by a bilateral degeneration of the optic nerves, causing insidious visual loss, typically starting during the first decade of life. The disease affects primary the retinal ganglion cells (RGC and their axons forming the optic nerve, which transfer the visual information from the photoreceptors to the lateral geniculus in the brain. Epidemiology The prevalence of the disease varies from 1/10000 in Denmark due to a founder effect, to 1/30000 in the rest of the world. Clinical description DOA patients usually suffer of moderate visual loss, associated with central or paracentral visual field deficits and color vision defects. The severity of the disease is highly variable, the visual acuity ranging from normal to legal blindness. The ophthalmic examination discloses on fundoscopy isolated optic disc pallor or atrophy, related to the RGC death. About 20% of DOA patients harbour extraocular multi-systemic features, including neurosensory hearing loss, or less commonly chronic progressive external ophthalmoplegia, myopathy, peripheral neuropathy, multiple sclerosis-like illness, spastic paraplegia or cataracts. Aetiology Two genes (OPA1, OPA3 encoding inner mitochondrial membrane proteins and three loci (OPA4, OPA5, OPA8 are currently known for DOA. Additional loci and genes (OPA2, OPA6 and OPA7 are responsible for X-linked or recessive optic atrophy. All OPA genes yet identified encode mitochondrial proteins embedded in the inner membrane and ubiquitously expressed, as are the proteins mutated in the Leber Hereditary Optic Neuropathy. OPA1 mutations affect mitochondrial fusion, energy metabolism, control of apoptosis, calcium clearance and maintenance of mitochondrial genome integrity. OPA3 mutations only affect the energy metabolism and the control of apoptosis. Diagnosis Patients are usually diagnosed during their early childhood, because of

  16. MUSAN: A Music, Speech, and Noise Corpus

    OpenAIRE

    Snyder, David; Chen, Guoguo; Povey, Daniel

    2015-01-01

    This report introduces a new corpus of music, speech, and noise. This dataset is suitable for training models for voice activity detection (VAD) and music/speech discrimination. Our corpus is released under a flexible Creative Commons license. The dataset consists of music from several genres, speech from twelve languages, and a wide assortment of technical and non-technical noises. We demonstrate use of this corpus for music/speech discrimination on Broadcast news and VAD for speaker identif...

  17. Enhancing Writing Pedagogy with Learner Corpus Data

    Science.gov (United States)

    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)…

  18. The Multimedia Adult ESL Learner Corpus.

    Science.gov (United States)

    Reder, Stephen; Harris, Kathryn; Setzler, Kristen

    2003-01-01

    Describes what may be the first of a new generation of corpora: the Multimedia Adult ESOL (English as a Second or Other Language) Learner Corpus. The corpus is notable for containing language produced by very low level learners in language classrooms and for the fact that the transcribed language remains linked to video recordings. (Author/VWL)

  19. Network Analysis with the Enron Email Corpus

    Science.gov (United States)

    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…

  20. Corpus-Based Investigations of Language Use.

    Science.gov (United States)

    Biber, Douglas; And Others

    1996-01-01

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

  1. Corpus delicti / Jüri Hain

    Index Scriptorium Estoniae

    Hain, Jüri, 1941-

    2001-01-01

    Leonhard Lapini, Sirje Runge, Andres Toltsi ja Mare Vindi 1960ndate lõpu ja 1970ndate alguse tööde näitusest "Corpus in spe" Deco galeriis ning nimetatud kunstnike ja Urmo Rausi uudisloomingu näitusest "Corpus" Tallinna Linnagaleriis

  2. Corpus delicti / Jüri Hain

    Index Scriptorium Estoniae

    Hain, Jüri, 1941-

    2001-01-01

    Leonhard Lapini, Sirje Runge, Andres Toltsi ja Mare Vindi 1960ndate lõpu ja 1970ndate alguse tööde näitusest "Corpus in spe" Deco galeriis ning nimetatud kunstnike ja Urmo Rausi uudisloomingu näitusest "Corpus" Tallinna Linnagaleriis

  3. To Teach Spoken Grammar With Corpus Studies

    Institute of Scientific and Technical Information of China (English)

    CHENG Li

    2016-01-01

    Using scripted materials in spoken language teaching has been challenged in recent years. Accordingly, many scholars have proposed to employ corpus in spoken language teaching. This article proved it is an efficient way to teach spoken grammar by combining scripted materials with authentic materials from corpus.

  4. Multiple system atrophy.

    Science.gov (United States)

    Peeraully, Tasneem

    2014-04-01

    Multiple system atrophy (MSA) is a rare adult-onset synucleinopathy associated with dysautonomia and the variable presence of poorly levodopa-responsive parkinsonism and/or cerebellar ataxia. Other clinical symptoms that can be associated with MSA include hyperreflexia, stridor, sleep apnea, and rapid eye movement sleep behavior disorder (RBD). Mean survival from time of diagnosis ranges between 6 to 10 years, and definitive diagnosis is made on autopsy with demonstration of oligodendroglial cytoplasmic inclusions consisting of fibrillar α-synuclein. Magnetic resonance imaging (MRI) may be positive for cruciform T2 hyperintensity within the pons (the "hot cross bun sign"), volume loss in the pons and cerebellum, and T2 signal loss in the dorsolateral putamen with hyperintense rim on fluid attenuated inversion recovery (FLAIR) sequencing. Although most cases are sporadic, genetic polymorphisms have been identified both in familial and sporadic cases of MSA, and influence observed phenotypes. Treatment is symptomatic, with both pharmacological and nonpharmacological strategies. There are currently no consensus guidelines on management. Current and future research is aimed at identifying biomarkers and developing disease-modifying therapies.

  5. Angiogenesis in the corpus luteum

    Directory of Open Access Journals (Sweden)

    Wulff Christine

    2003-11-01

    Full Text Available Abstract The corpus luteum (CL is a site of intense angiogenesis. Within a short period, this is followed either by controlled regression of the microvascular tree in the non-fertile cycle, or maintenance and stabilisation of the new vasculature a conceptual cycle. The molecular regulation of these diverse aspects is examined. The CL provides a unique model system in which to study the cellular and molecular regulation of angiogenesis. Vascular endothelial growth factor (VEGF has been found to have a major role in the CL. By targeting its action at specific stages of the luteal phase in vivo by antagonists, profound inhibitory effects on luteal angiogenesis and function are observed.

  6. Interactions between Corpus and Lexicon

    DEFF Research Database (Denmark)

    This collection of papers stems from the Fifth Workshop on the Representation and Processing of Sign Languages, held in May 2012 as a satellite to the Language Resources and Evaluation Conference in Istanbul. While there has been occasional attention for sign languages at the main LREC conference......, the main focus there is on spoken languages in their written and spoken forms. This series of workshops, however, offers a forum for researchers focussing on sign languages. For the third time, the workshop had sign language corpora as its main topic. This time, the focus was on the interaction between...... corpus and lexicon. More than half of the papers presented contribute to this topic. Once again, the papers at this workshop clearly identify the potentials of even closer cooperation between sign linguists and sign language engineers, and we think it is events like this that contribute a lot to a better...

  7. 外伤性胼胝体损伤的MRI诊断%MRI diagnosis of traumatic injury to corpus cllosum

    Institute of Scientific and Technical Information of China (English)

    朱锡德; 费昶; 衡雪源

    2010-01-01

    Objective To observe the MRI features of traumatic brainin jury to corpus callosum and provide valuable diagnostic information for clinical application. Methods Clinical and radiological data were retrospectively analyzed in 20 MRI-diagnosed patients as having traunmtic brain mjury to corpus callosum. Results Traumatic injury to corpus callosum was rather rare in brain trauma.Most traumatic injury to corpus callosum was non-hemorrhagic and its lesion mainly laid at its body or splenium,sometimes at genu,but rarely at rostrum.Traumatic injury to corpus callosum,being one of the common manifestations in diffuse axonal injury(DAI), could be demonstrated slight hyperintense signal on TI WI and T2WI in early phase.The injury site shrank and liquefaction necrosis appeared in the lesion at the late-mid-injured period with softened focus or gliai scar.MRI showed hyperintense T1 and T2 signal, similar to the signal of the cerebrospinal fluid and demonstrated ventriculomegaly in the corresponding parts.DWI showed hyperintense signal in the lesion in acute and subacutc stages:with time prolonged,isointense signal of the normal brain tissue was found and signal of the cerebrospinal fluid appeared in the present of softened focus.Conclusion Attention should be paid to the traumatic injury to corpus callosum,an indicator for severe trauma or disease.MRI,a sensitive and multi-directional imaging,is superior in detecting non-hemorrhagic injury to the corpus callosum.%[目的] 观察颅脑创伤致胼胝体损伤的MRI表现,为临床提供有价值的诊断信息,提高颅脑创伤的救治水平. 方法 回顾分析临沂市人民医院神经外科自2007年至2009年收治疗的20例MRI证实为胼胝体损伤患者的临床、影像资料,观察其临床表现及MRI各序列特征. 结果 外伤性胼胝体损伤在临床较为少见,以非出血性损伤为主,损伤部位常见于体部及压部,少数位于膝部,嘴部损伤罕见.对于早期非出血

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

    Science.gov (United States)

    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

  9. Idiopathic atrophie blanche.

    Science.gov (United States)

    Amato, Lauretta; Chiarini, Caterina; Berti, Samantha; Massi, Daniela; Fabbri, Paolo

    2006-01-01

    clinical, serologic, histopathologic, and immunopathologic findings, a diagnosis of idiopathic atrophie blanche was made. The patient was treated with dapsone (50 mg p.o. q.d.) and pentoxifylline (400 mg p.o. t.i.d.) with pain relief and complete resolution of the ulcerations after 6 weeks of therapy.

  10. CORPUS AND FREQUENCY GRAMMAR CORPUS VOCABULARY OF THE CHURCH SLAVONIC LANGUAGE AS PART OF THE RUSSIAN NATIONAL CORPUS

    Directory of Open Access Journals (Sweden)

    E. R. Dobrushina

    2015-01-01

    Full Text Available The article describes the current  state of  work on the Corpus of Church Slavonic within the Russian National Corpus. The Corpus is different from the collection of texts by the presence of a special markup (grammatical, structural, metatextual and  the  possibility to  search by this markup. The article considers the content, describes the main genre headings, according to which the texts included in the Corpus are distributed, describes  the principles of the metamarkup that differ from those used in other Corpuses  within the Russian National Corpus. Where necessary, the historical information,  on the basis of  which a certain decision was made, is provided. Since typing search queries on the keyboard presents certain difficulties  for Church Slavonic texts, we offer several options for simplified spelling transmission, which enable a person to enter a query with limited capabilities of a standard keyboard. Finally, the article describes the frequency grammar vocabulary created during the work on the project.

  11. [Atrophy of the bone marrow].

    Science.gov (United States)

    Dziecioł, J; Kemona, A; Sulik, M; Sulkowski, S; Brykalska, A; Sobaniec-Lotowska, M; Ostapiuk, H

    1990-01-01

    The authors made a quantitative analysis of the active hematopoietic tissue of the bone marrow with particular consideration of its atrophy in the course of various diseases. The material consisted of 407 non-selected autopsy cases. For a morphometric analysis the bone marrow was sampled from the sternum, ala ossis illi and spine. In the quantitative analysis of the active hematopoietic tissue we took into account age groups as quantitative changes appear with age. Atrophy of the bone marrow was in 19.4% of the studied cases. The presence of bone marrow atrophy was found in the course of various diseases, most frequently neoplastic, particularly in patients aged from 50 to 59 years.

  12. A Corpus-Based Study of Idioms in Academic Speech.

    Science.gov (United States)

    Simpson, Rita; Mendis, Dushyanthi

    2003-01-01

    Addresses the advantages and limitations of a corpus-based approach to researching and teaching idioms in a specific genre by drawing on a specialized corpus of 1.7 million words of academic discourse, the Michigan Corpus of Academic Spoken English. Argues that evidence from such a corpus can be informative for language teachers when the primary…

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

    Science.gov (United States)

    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.

  14. A ROUGH GUIDE TO DOING CORPUS STYLISTICS

    National Research Council Canada - National Science Library

    Tania M. G. Shepherd; Tony Berber Sardinha

    2015-01-01

    .... The second is to analyse a prize winning novel by English writer Julian Barnes, by resorting to the tenets and working tools of one of the newest branch of Stylistics, the so-called Corpus stylistics...

  15. Notes on Compiling a Corpus- Based Dictionary*

    African Journals Online (AJOL)

    rbr

    words and phrases in a language, a fact that is often underestimated or even disliked by ... Differences between the traditional approach and the corpus approach ... almost no attention is paid to nouns, the largest of the word classes. The latter.

  16. Optic atrophy and glaucomatous cupping.

    Science.gov (United States)

    Radius, R L; Maumenee, A E

    1978-02-01

    We reviewed 170 eyes of 112 patients with optic atrophy from various causes. Special attention was directed towards measured cup:disk ratios as well as presence of glaucomatous-like cupping of the optic nerve head. We observed a small but significant increase in nerve head cupping in eyes with optic atrophy when compared to contralateral eyes, as well as to eyes of 50 diabetic patients. No characteristic glaucomatous disk changes were documented. We evaluated these findings with respect to possible causes of glaucomatous disk and field changes.

  17. Integrating corpus consultation in language studies

    OpenAIRE

    Angela Chambers

    2005-01-01

    peer-reviewed Alongside developments in language research, the potential of corpora as a resource in language learning and teaching has been evident to researchers and teachers since the late 1960s. Despite publications which emphasise the benefits of corpus consultation for language learners (Bernardini, 2002; Kennedy & Miceli, 2001), there is little evidence to suggest that direct corpus consultation is coming to be seen as a complement or alternative to consultation of a dictionary, cou...

  18. The Overall Introduction of Corpus Linguistics

    Institute of Scientific and Technical Information of China (English)

    许琳华; 李旭辉; 杨晓伟

    2011-01-01

    @@ i.Preface Corpus can be defined as "…a collection of texts assumed to be represent-ative of a given language put together so that it can be used for linguistic analy-sis" (Tognini - Bonelli 2001 : 2).It is built through collecting authentic lan-guage material.A corpus is a very important basis for language teaching and research.It is also a very important source of information for complication of dictionaries, grammar books and teaching materials.

  19. Types of SMA (Spinal Muscular Atrophy)

    Science.gov (United States)

    ... genes other than the SMN1 gene. Spinal Muscular Atrophy Respiratory Distress (SMARD) SMARD is a very rare ... and 50. It causes muscle weakness and wasting (atrophy) throughout the body, which is most noticeable in ...

  20. Genetics Home Reference: dentatorubral-pallidoluysian atrophy

    Science.gov (United States)

    ... Understand Genetics Home Health Conditions DRPLA dentatorubral-pallidoluysian atrophy Enable Javascript to view the expand/collapse boxes. ... PDF Open All Close All Description Dentatorubral-pallidoluysian atrophy , commonly known as DRPLA , is a progressive brain ...

  1. The Bulgarian-Polish-Russian parallel corpus

    Directory of Open Access Journals (Sweden)

    Maksim Duškin

    2015-11-01

    Full Text Available The Bulgarian-Polish-Russian parallel corpus The Semantics Laboratory Team of Institute of Slavic Studies of Polish Academy of Sciences is planning to begin work on the creation of a Bulgarian-Polish-Russian parallel corpus. The three selected languages are representatives of the main groups of Slavic languages: Bulgarian represents the southern group of Slavic languages, Polish – the western group of Slavic languages, Russian – the eastern group of Slavic languages. Our project will be the first parallel corpus of these three languages. The planned corpus will be based on material, dating from one period (the 20th century and will have a synchronous nature. The project will not constitute the sum of the separate corpora of selected languages. One of the problems with creating multilingual parallel corpora are different proportions of translated texts between the selected languages, for example, Polish literature is often translated into Bulgarian, but not vice versa. Bulgarian, Russian and Polish differ typologically – Bulgarian is an analytic language, Polish and Russian are synthetic. The parallel corpus should have compatible annotation, while taking into account the characteristic features of the selected languages. We hope that the Bulgarian-Polish-Russian parallel corpus will serve as a source of linguistic material of contrastive language studies and may prove to be a big help for linguists, translators, terminologists and students of linguistics. The results of our work will be available on the Internet.

  2. Compiling a Corpus for Teaching Medical Translation

    Directory of Open Access Journals (Sweden)

    Elizabeth de la Teja Bosch

    2014-04-01

    Full Text Available Background: medical translation has countless documentary sources; the major difficulty lies in knowing how to assess them. The corpus is the ideal tool to perform this activity in a rapid and reliable way, and to define the learning objectives based on text typology and oriented towards professional practice.Objective: to compile an electronic corpus that meets the requirements of the professional practice to perform specialized medical translation. Methods: a pedagogical research was conducted in the province of Cienfuegos. The units of analysis involved records from translators of the Provincial Medical Sciences Information Center and specialized translators in this field, who completed a questionnaire to accurately determine their information needs, conditioning the corpus design criteria. The analysis of a set of texts extracted from highly reputable sources led to the text selection and final compilation. Subsequently, the validation of the corpus as a documentary tool for teaching specialized medical translation was performed. Results: there was a concentration of translation assignments in the topics: malignant tumors, hypertension, heart disease, diabetes mellitus and pneumonias. The predominant text typologies were: evaluative and dissemination of current research, with plenty original articles and reviews. The text corpus design criteria were: unannotated, documented, specialized, monitor and comparable. Conclusions: the corpus is a useful tool to show the lexical, terminological, semantic, discursive and contextual particularities of biomedical communication. It allows defining learning objectives and translation problems. Key words: teaching; translating; medicine

  3. 77 FR 34034 - Corpus Christi Liquefaction, LLC; Cheniere Corpus Christi Pipeline, L.P.; Notice of Intent To...

    Science.gov (United States)

    2012-06-08

    ... Energy Regulatory Commission Corpus Christi Liquefaction, LLC; Cheniere Corpus Christi Pipeline, L.P.; 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...

  4. Learner corpora: the case of the NOSE corpus

    Directory of Open Access Journals (Sweden)

    Ana Díaz-Negrillo

    2012-02-01

    Full Text Available This paper provides a brief overview of the scope of learner corpus research and describes a learner corpus by Spanish university students of English, the NOn-native Spanish corpus of English (NOSE. It presents the corpus data, its annotation and how it can be retrieved and exploited for research purposes in the areas of interlanguage studies and automatic recognition of learner-specific features. It also reviews the various research topics that have been investigated in the corpus.

  5. Microvascular endothelial cells of the corpus luteum

    Directory of Open Access Journals (Sweden)

    Spanel-Borowski Katherina

    2003-11-01

    Full Text Available Abstract The cyclic nature of the capillary bed in the corpus luteum offers a unique experimental model to examine the life cycle of endothelial cells, involving discrete physiologically regulated steps of angiogenesis, blood vessel maturation and blood vessel regression. The granulosa cells and theca cells of the developing antral follicle and the steroidogenic cells of the corpus luteum produce and respond to angiogenic factors and vasoactive peptides. Following ovulation the neovascularization during the early stages of corpus luteum development has been compared to the rapid angiogenesis observed during tumor formation. On the other end of the spectrum, the microvascular endothelial cells are the first cells to undergo apoptosis at the onset of corpus luteum regression. Important insights on the morphology and function of luteal endothelial cells have been gained from a combination of in vitro and in vivo studies on endothelial cells. Endothelial cells communicate with cells comprising the functional unit of the corpus luteum, i.e., other vascular cells, steroidogenic cells, and immune cells. This review is designed to provide an overview of the types of endothelial cells present in the corpus luteum and their involvement in corpus luteum development and regression. Available evidence indicates that microvascular endothelial cells of the corpus luteum are not alike, and may differ during the process of angiogenesis and angioregression. The contributions of vasoactive peptides generated by the luteal endothelin-1 and the renin-angiotensin systems are discussed in context with the function of endothelial cells during corpus luteum formation and regression. The ability of two cytokines, tumor necrosis factor alpha and interferon gamma, are evaluated as paracrine mediators of endothelial cell function during angioregression. Finally, chemokines are discussed as a vital endothelial cell secretory products that contribute to the recruitment of

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

    Science.gov (United States)

    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…

  7. 77 FR 2448 - Special Local Regulation; HITS Triathlon; Corpus Christi Bayfront, Corpus Christi, TX

    Science.gov (United States)

    2012-01-18

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

  8. Mitochondrial signaling contributes to disuse muscle atrophy

    Science.gov (United States)

    Wiggs, Michael P.; Duarte, Jose A.; Zergeroglu, A. Murat; Demirel, Haydar A.

    2012-01-01

    It is well established that long durations of bed rest, limb immobilization, or reduced activity in respiratory muscles during mechanical ventilation results in skeletal muscle atrophy in humans and other animals. The idea that mitochondrial damage/dysfunction contributes to disuse muscle atrophy originated over 40 years ago. These early studies were largely descriptive and did not provide unequivocal evidence that mitochondria play a primary role in disuse muscle atrophy. However, recent experiments have provided direct evidence connecting mitochondrial dysfunction to muscle atrophy. Numerous studies have described changes in mitochondria shape, number, and function in skeletal muscles exposed to prolonged periods of inactivity. Furthermore, recent evidence indicates that increased mitochondrial ROS production plays a key signaling role in both immobilization-induced limb muscle atrophy and diaphragmatic atrophy occurring during prolonged mechanical ventilation. Moreover, new evidence reveals that, during denervation-induced muscle atrophy, increased mitochondrial fragmentation due to fission is a required signaling event that activates the AMPK-FoxO3 signaling axis, which induces the expression of atrophy genes, protein breakdown, and ultimately muscle atrophy. Collectively, these findings highlight the importance of future research to better understand the mitochondrial signaling mechanisms that contribute to disuse muscle atrophy and to develop novel therapeutic interventions for prevention of inactivity-induced skeletal muscle atrophy. PMID:22395111

  9. INTEGRATING CORPUS CONSULTATION IN LANGUAGE STUDIES

    Directory of Open Access Journals (Sweden)

    Angela Chambers

    2005-05-01

    Full Text Available Alongside developments in language research, the potential of corpora as a resource in language learning and teaching has been evident to researchers and teachers since the late 1960s. Despite publications which emphasise the benefits of corpus consultation for language learners (Bernardini, 2002; Kennedy & Miceli, 2001, there is little evidence to suggest that direct corpus consultation is coming to be seen as a complement or alternative to consultation of a dictionary, course book, or grammar by the majority of learners. There is thus a need for research to underpin the integration of corpora and concordancing in the language-learning environment.This study begins with an account of published research relating to course design and structure in the area of corpus consultation by language learners. The focus then narrows to the initial training of learners in corpus consultation, using as an example a course involving undergraduate students on several language degree programmes. The results of the students' consultation of the corpora are examined, including choice of search word(s, analytical skills, the problems encountered, and their evaluation of the activity. The results reveal how corpus consultation can complement traditional language-learning resources, while also raising questions concerning its integration in the language-learning environment.

  10. KoralQuery -- A General Corpus Query Protocol

    DEFF Research Database (Denmark)

    Bingel, Joachim; Diewald, Nils

    2015-01-01

    The task-oriented and format-driven development of corpus query systems has led to the creation of numerous corpus query languages (QLs) that vary strongly in expressiveness and syntax. This is a severe impediment for the interoperability of corpus analysis systems, which lack a common protocol....... In this paper, we present KoralQuery, a JSON-LD based general corpus query protocol, aiming to be independent of particular QLs, tasks and corpus formats. In addition to describing the system of types and operations that KoralQuery is built on, we exemplify the representation of corpus queries in the serialized...

  11. Neuronal involvement in muscular atrophy

    Directory of Open Access Journals (Sweden)

    Bruno Alejandro Cisterna

    2014-12-01

    Full Text Available The innervation of skeletal myofibers exerts a crucial influence on the maintenance of muscle tone and normal operation. Consequently, denervated myofibers manifest atrophy, which is preceded by an increase in sarcolemma permeability. Recently, de novo expression of hemichannels formed by connexins and other none selective channels, including P2X7 receptors, TRPV2 channels were demonstrated in denervated fast skeletal muscles. The denervation-induced atrophy was drastically prevented in denervated muscles deficient in connexins 43 and 45. Nonetheless, the transduction mechanism by which the nerve represses the expression of the above mentioned none selective channels remains unknown. The paracrine action of extracellular signaling molecules including ATP, neurotrophic factors (i.e., BDNF, agrin/Lrp4/MuSK and acetylcholine are among the possible perpetrators of repression for connexin expression. This review discusses the possible role of relevant factors in maintaining the normal functioning of fast skeletal muscles and suppression of connexin hemichannel expression.

  12. A Corpus for Evidence Based Medicine Summarisation

    Directory of Open Access Journals (Sweden)

    Diego Mollá Aliod

    2012-09-01

    Full Text Available Background Automated text summarisers that find the best clinical evidence reported in collections of medical literature are of potential benefit for the practice of Evidence Based Medicine (EBM. Research and development of text summarisers for EBM, however, is impeded by the lack of corpora to train and test such systems. Aims To produce a corpus for research in EBM summarisation. Method We sourced the “Clinical Inquiries” section of the Journal of Family Practice (JFP and obtained a sizeable sample of questions and evidence based summaries. We further processed the summaries by combining automated techniques, human annotations, and crowdsourcing techniques to identify the PubMed IDs of the references. Results The corpus has 456 questions, 1,396 answer components, 3,036 answer justifications, and 2,908 references. Conclusion The corpus is now available for the research community at http://sourceforge.net/projects/ebmsumcorpus.

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

    Directory of Open Access Journals (Sweden)

    Claire Kennedy

    2010-02-01

    Full Text Available 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 semester-long apprenticeship in corpus use which does not demand of them the high level of language proficiency, attention to detail in observation, and logical rigour that we consider necessary for rewarding work in the learner-as-researcher role. Instead, we introduce a corpus initially as an aid to the imagination in writing, and then to achieving accuracy through specific grammatical problem solving. We see this as the groundwork for subsequent development of the students’ research skills with corpus data. This paper describes the approach we have adopted to the corpus apprenticeship and reports on an evaluation of its effectiveness through case studies of three students and their use of a corpus and bilingual dictionary as reference resources when writing. Drawing on insights from the case studies, we outline a working definition of corpus-consultation literacy for our learning context and identify some refinements to be made to our apprenticeship.

  14. Using a Corpus for Teaching Turkish Morphology

    CERN Document Server

    Guvenir, H A; Oflazer, Kemal

    1995-01-01

    This paper reports on the preliminary phase of our ongoing research towards developing an intelligent tutoring environment for Turkish grammar. One of the components of this environment is a corpus search tool which, among other aspects of the language, will be used to present the learner sample sentences along with their morphological analyses. Following a brief introduction to the Turkish language and its morphology, the paper describes the morphological analysis and ambiguity resolution used to construct the corpus used in the search tool. Finally, implementation issues and details involving the user interface of the tool are discussed.

  15. Linguistics in the digital humanities: (computational corpus linguistics

    Directory of Open Access Journals (Sweden)

    Kim Ebensgaard Jensen

    2014-12-01

    Full Text Available Corpus linguistics has been closely intertwined with digital technology since the introduction of university computer mainframes in the 1960s. Making use of both digitized data in the form of the language corpus and computational methods of analysis involving concordancers and statistics software, corpus linguistics arguably has a place in the digital humanities. Still, it remains obscure and fi gures only sporadically in the literature on the digital humanities. Th is article provides an overview of the main principles of corpus linguistics and the role of computer technology in relation to data and method and also off ers a bird's-eye view of the history of corpus linguistics with a focus on its intimate relationship with digital technology and how digital technology has impacted the very core of corpus linguistics and shaped the identity of the corpus linguist. Ultimately, the article is oriented towards an acknowledgment of corpus linguistics' alignment with the digital humanities.

  16. arTenTen: Arabic Corpus and Word Sketches

    Directory of Open Access Journals (Sweden)

    Tressy Arts

    2014-12-01

    The article also presents the ‘sketch grammar’ (the basis for the word sketches in detail, describes the process of building and processing the corpus, and considers the role of the corpus in additional research on Arabic.

  17. Corpus-based lexicography for lesser-resourced languages ...

    African Journals Online (AJOL)

    user

    In many cases sincere attempts at corpus designs and the compilation of ..... for example, Prinsloo and De Schryver (2003: 110) give a schematic illustration .... graphic rulers and block systems could be compiled from a corpus as small as.

  18. Two directions of change in one corpus

    DEFF Research Database (Denmark)

    Jensen, Marie Møller

    2015-01-01

    Cheshire et al. (2005) argue that different levels of language do not necessarily follow the same patterns of change over time. In an attempt to test this prediction, this article reports on a comparison between two quantitative corpus studies of Tyneside English which are partly based on the sam...

  19. Inflation Metaphor in the TIME Magazine Corpus

    Science.gov (United States)

    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…

  20. Rheumatic diseases in the Corpus Hippocraticum

    Directory of Open Access Journals (Sweden)

    G. Squillace

    2011-09-01

    Full Text Available Medecine of V and IV centuries B.C. attested in the Corpus Hippocraticum ascribes all diseases to the rheuma, i.e. the flux of humours into the body. This flux produces not only the rise of cold, hoarsness, cough, reddenings, dropsy, but also arthritis, sciatica, gout.

  1. Two directions of change in one corpus

    DEFF Research Database (Denmark)

    Jensen, Marie Møller

    2015-01-01

    Cheshire et al. (2005) argue that different levels of language do not necessarily follow the same patterns of change over time. In an attempt to test this prediction, this article reports on a comparison between two quantitative corpus studies of Tyneside English which are partly based on the same...

  2. CORPUS-BASED TRANSLATION RESEARCH: ITS ...

    African Journals Online (AJOL)

    Corpus-based translation research emerged in the late 1990s as a new area of re- search in ... tics goes back to the early 1960s when the “first-generation” of one-million .... and then takes an average count at the end; allowing one to compare.

  3. The Yale-Classical Archives Corpus

    Directory of Open Access Journals (Sweden)

    Christopher William White

    2016-07-01

    Full Text Available The Yale-Classical Archives Corpus (YCAC contains harmonic and rhythmic information for a dataset of Western European Classical art music. This corpus is based on data from classicalarchives.com, a repository of thousands of user-generated MIDI representations of pieces from several periods of Western European music history. The YCAC makes available metadata for each MIDI file, as well as a list of pitch simultaneities ("salami slices" in the MIDI file. Metadata include the piece's composer, the composer's country of origin, date of composition, genre (e.g., symphony, piano sonata, nocturne, etc., instrumentation, meter, and key. The processing step groups the file's pitches into vertical slices each time a pitch is added or subtracted from the texture, recording the slice's offset (measured in the number of quarter notes separating the event from the file's beginning, highest pitch, lowest pitch, prime form, scale-degrees in relation to the global key (as determined by experts, and local key information (as determined by a windowed key-profile analysis. The corpus contains 13,769 MIDI files by 571 composers yielding over 14,051,144 vertical slices. This paper outlines several properties of this corpus, along with a representative study using this dataset.

  4. A Massive Chinese Floral Corpus Completed

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Through the efforts of several generations of Chinese botanists over the past 50years, a massive 80-volume corpus (in 126 books) on China's flora,Flora Reipublicae Popularis Sinicae (Chinese edition), has finally been completed. This was announced at a press meeting on March 31 in Beijing.

  5. Mitochondrial signaling contributes to disuse muscle atrophy

    OpenAIRE

    Powers, Scott K.; Wiggs, Michael P.; Duarte, Jose A.; Zergeroglu, A. Murat; Demirel, Haydar A.

    2012-01-01

    It is well established that long durations of bed rest, limb immobilization, or reduced activity in respiratory muscles during mechanical ventilation results in skeletal muscle atrophy in humans and other animals. The idea that mitochondrial damage/dysfunction contributes to disuse muscle atrophy originated over 40 years ago. These early studies were largely descriptive and did not provide unequivocal evidence that mitochondria play a primary role in disuse muscle atrophy. However, recent exp...

  6. 38 CFR 3.263 - Corpus of estate; net worth.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Corpus of estate; net....263 Corpus of estate; net worth. (a) General. The following rules are for application in determining the corpus of estate of a parent where dependency is a factor under § 3.250, and the net worth of...

  7. 33 CFR 110.75 - Corpus Christi Bay, Tex.

    Science.gov (United States)

    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....

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

    Science.gov (United States)

    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…

  9. The Nordic Dialect Corpus – a joint research infrastructure

    Directory of Open Access Journals (Sweden)

    Janne Bondi Johannessen

    2011-06-01

    Full Text Available The paper describes the Nordic Dialect Corpus as of June 2010. The corpus is a tool that combines a number of useful features that together makes it a unique and very advanced resource for researchers of many fields of language search. The corpus is web-based and features full audio-visual representation linked to transcriptions and translations.

  10. KoralQuery -- A General Corpus Query Protocol

    DEFF Research Database (Denmark)

    Bingel, Joachim; Diewald, Nils

    2015-01-01

    The task-oriented and format-driven development of corpus query systems has led to the creation of numerous corpus query languages (QLs) that vary strongly in expressiveness and syntax. This is a severe impediment for the interoperability of corpus analysis systems, which lack a common protocol...... format and illustrate use cases in the KorAP project....

  11. An annotated corpus for the analysis of VP ellipsis

    NARCIS (Netherlands)

    Bos, Johan; Spenader, J.

    2011-01-01

    Verb Phrase Ellipsis (VPE) has been studied in great depth in theoretical linguistics, but empirical studies of VPE are rare. We extend the few previous corpus studies with an annotated corpus of VPE in all 25 sections of the Wall Street Journal corpus (WSJ) distributed with the Penn Treebank. We an

  12. An annotated corpus for the analysis of VP ellipsis

    NARCIS (Netherlands)

    Bos, Johan; Spenader, J.

    2011-01-01

    Verb Phrase Ellipsis (VPE) has been studied in great depth in theoretical linguistics, but empirical studies of VPE are rare. We extend the few previous corpus studies with an annotated corpus of VPE in all 25 sections of the Wall Street Journal corpus (WSJ) distributed with the Penn Treebank. We

  13. MEANTIME, the NewsReader Multilingual Event and Time Corpus

    NARCIS (Netherlands)

    Minard, A.-L.; Speranza, M; Urizar, R.; Altuna, B.; Erp, van M.G.J.; Schoen, A.M.; Son, van C.M.

    2016-01-01

    In this paper, we present the NewsReader MEANTIME corpus, a semantically annotated corpus of Wikinews articles. The corpus consists of 480 news articles, i.e. 120 English news articles and their translations in Spanish, Italian, and Dutch. MEANTIME contains annotations at different levels. The docum

  14. Cube propagation for focal brain atrophy estimation

    DEFF Research Database (Denmark)

    Pai, Akshay Sadananda Uppinakudru; Sørensen, Lauge; Darkner, Sune

    2013-01-01

    or localization of atrophy and subsequent summing to an ROI measure of atrophy. ST and SF only offer whole ROI atrophy measures. JI and SF suffer from a lack of precision originating from respectively approximating a space and a time integral by a finite sum. VM suffers from a high computational burden and the ST......Precise and robust whole brain, ventricle, and hippocampal atrophy measurements are important as they serve as biomarkers for Alzheimer’s disease. They are used as secondary outcomes in drug trials, and they correlate with the cognitive scores. When two successive scans are non-linearly aligned...

  15. The Use of Corpus for Close Synonyms

    Directory of Open Access Journals (Sweden)

    M. Naci KAYAOĞLU

    2013-04-01

    Full Text Available Problem Statement: Using corpora is still in its infancy in foreign language classes in spite of its great benefits and potential to offer solutions to the various challenges in foreign language instruction both for teachers and learners. This partly stems from a lack of interest and practical knowledge about the pedagogic role that the corpora can play. There is a pressing need to convince teachers of the great benefits of corpora with empirical data.Purpose of Study: This research aims to explore the feasibility of using a corpus to help students differentiate between close synonyms which have similar meanings but cannot be substituted one for the other.Method: This is quasi-experimental research based on a pre and post-test (one shot design design. To this end, participants were introduced to the Corpus of Contemporary American English (COCA and asked to refer to the corpus when deciding the appropriate close synonym in the 50 sentences given. Participants were also interviewed upon completion of the task with the COCA about their use of corpus.Findings and Results: The t-test showed that the use of corpus for deciding on close synonyms proved to be very effective as there was a statistically significant difference in participants‟ performance on the vocabulary portion of the pretest and post-test.Conclusion and Recommendations: The present paper suggests that corpora can be a very rich and effective source of empirical data both for teachers and students to make foreign language learning more meaningful and enjoyable. Providing learners more exposure to authentic examples, corpora can be utilized for pedagogic purposes from syllabus design to materials development. Yet, it needs to be integrated into language courses. Teachersshould be made fully aware of what corpora offer for language teaching.

  16. Concept annotation in the CRAFT corpus

    Directory of Open Access Journals (Sweden)

    Bada Michael

    2012-07-01

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

  17. 33 CFR 334.800 - Corpus Christi Bay, Tex.; seaplane restricted area, U.S. Naval Air Station, Corpus Christi.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Corpus Christi Bay, Tex.; seaplane restricted area, U.S. Naval Air Station, Corpus Christi. 334.800 Section 334.800 Navigation and... RESTRICTED AREA REGULATIONS § 334.800 Corpus Christi Bay, Tex.; seaplane restricted area, U.S. Naval...

  18. Non-invasive diagnosis of gastric mucosal atrophy in an asymptomatic population with high prevalence of gastric cancer

    Institute of Scientific and Technical Information of China (English)

    Antonio Rollan; Catterina Ferreccio; Alessandra Gederlini; Carolina Serrano; Javiera Torres; Paul Harris

    2006-01-01

    AIM: To validate a non-invasive method to detect gastric mucosal atrophy in a Chilean population with high prevalence of gastric cancer and a poor survival rate.METHODS: We first determined the optimal cut-off level of serum pepsinogen (PG)-1, PG-1/PG-2 ratio and 17-gastrin in 31 voluntary symptomatic patients (mean age: 66.1 years), of them 61% had histologically confirmed gastric atrophy. Then, in a population-based sample of 536 healthy individuals (209 residents in counties with higher relative risk and 327 residents in counties with lower relative risk for gastric cancer),we measured serum anti-Hpylori antibodies, PG and 17-gastrin and estimated their risk of gastric cancer.RESULTS: We found that serum PG-1 < 61.5 μg/L,PG-1/PG-2 ratio < 2.2 and 17-gastrin > 13.3 pmol/L had a high specificity (91%-100%) and a fair sensitivity (56%-78%) to detect corpus-predominant atrophy.Based on low serum PG-1 and PG-1/PG-2 ratio together as diagnostic criteria, 12.5% of the asymptomatic subjects had corpus-predominant atrophy (0% of those under 25 years and 20.2% over 65 years old). The frequency of gastric atrophy was similar (12% vs 13%)but H pylori infection rate was slightly higher (77% vs 71%) in the high-risk compared to the low-risk counties.Based on their estimated gastric cancer risk, individuals were classified as: low-risk group (no H pylori infection and no atrophy; n = 115; 21.4%); moderate-risk group (H pylori infection but no atrophy; n = 354, 66.0%);and high-risk group (gastric atrophy, with or without H pylori infection; n = 67, 12.5%). The high-risk group was significantly older (mean age: 61.9 ± 13.3 years),more frequently men and less educated as compared with the low-risk group.CONCLUSION: We propose to concentrate on an upper gastrointestinal endoscopy for detection of early gastric cancer in the high-risk group. This intervention model could improve the poor prognosis of gastric cancer in Chile.

  19. Applying corpus methods to written academic texts: Explorations of MICUSP

    Directory of Open Access Journals (Sweden)

    Ute Römer

    2010-08-01

    Full Text Available Based on explorations of the Michigan Corpus of Upper-level Student Papers (MICUSP, the present paper provides an introduction to the central techniques in corpus analysis, including the creation and examination of word lists, keyword lists, concordances, and cluster lists. It also presents a MICUSP-based case study of the demonstrative pronoun this and the distribution and use of its attended and unattended forms in different disciplinary subsets of the corpus. The paper aims to demonstrate how corpus linguistics and corpus methods can contribute to writing research and provide fruitful insights into student academic writing.

  20. EXOSC8 mutations alter mRNA metabolism and cause hypomyelination with spinal muscular atrophy and cerebellar hypoplasia.

    Science.gov (United States)

    Boczonadi, Veronika; Müller, Juliane S; Pyle, Angela; Munkley, Jennifer; Dor, Talya; Quartararo, Jade; Ferrero, Ileana; Karcagi, Veronika; Giunta, Michele; Polvikoski, Tuomo; Birchall, Daniel; Princzinger, Agota; Cinnamon, Yuval; Lützkendorf, Susanne; Piko, Henriett; Reza, Mojgan; Florez, Laura; Santibanez-Koref, Mauro; Griffin, Helen; Schuelke, Markus; Elpeleg, Orly; Kalaydjieva, Luba; Lochmüller, Hanns; Elliott, David J; Chinnery, Patrick F; Edvardson, Shimon; Horvath, Rita

    2014-07-03

    The exosome is a multi-protein complex, required for the degradation of AU-rich element (ARE) containing messenger RNAs (mRNAs). EXOSC8 is an essential protein of the exosome core, as its depletion causes a severe growth defect in yeast. Here we show that homozygous missense mutations in EXOSC8 cause progressive and lethal neurological disease in 22 infants from three independent pedigrees. Affected individuals have cerebellar and corpus callosum hypoplasia, abnormal myelination of the central nervous system or spinal motor neuron disease. Experimental downregulation of EXOSC8 in human oligodendroglia cells and in zebrafish induce a specific increase in ARE mRNAs encoding myelin proteins, showing that the imbalanced supply of myelin proteins causes the disruption of myelin, and explaining the clinical presentation. These findings show the central role of the exosomal pathway in neurodegenerative disease.

  1. Disconnection mechanism and regional cortical atrophy contribute to impaired processing of facial expressions and theory of mind in multiple sclerosis

    DEFF Research Database (Denmark)

    Mike, Andrea; Strammer, Erzsebet; Aradi, Mihaly

    2013-01-01

    healthy controls. We assessed overall brain cortical thickness in patients with multiple sclerosis and the scanned healthy controls, and measured the total and regional T1 and T2 white matter lesion volumes in patients with multiple sclerosis. Performances in tests of recognition of mental states...... and emotions from facial expressions and eye gazes correlated with both total T1-lesion load and regional T1-lesion load of association fiber tracts interconnecting cortical regions related to visual and emotion processing (genu and splenium of corpus callosum, right inferior longitudinal fasciculus, right...... inferior fronto-occipital fasciculus, uncinate fasciculus). Both of these tests showed correlations with specific cortical areas involved in emotion recognition from facial expressions (right and left fusiform face area, frontal eye filed), processing of emotions (right entorhinal cortex) and socially...

  2. Genetics Home Reference: spinal and bulbar muscular atrophy

    Science.gov (United States)

    ... Kennedy spinal and bulbar muscular atrophy Kennedy's disease SBMA X-linked spinal and bulbar muscular atrophy Related ... Natural history of spinal and bulbar muscular atrophy (SBMA): a study of 223 Japanese patients. Brain. 2006 ...

  3. Corpus Christi, Nueces, and Aransas Bays

    Science.gov (United States)

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

    2015-01-01

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

  4. Oxyntic gastric atrophy in Helicobacter pylori gastritis is distinct from autoimmune gastritis.

    Science.gov (United States)

    Venerito, Marino; Varbanova, Mariya; Röhl, Friedrich-Wilhelm; Reinhold, Dirk; Frauenschläger, Katrin; Jechorek, Doerthe; Weigt, Jochen; Link, Alexander; Malfertheiner, Peter

    2016-08-01

    To assess characteristics of oxyntic gastric atrophy (OGA) in autoimmune gastritis (AIG) compared with OGA as a consequence of Helicobacter pylori infection. Patients undergoing oesophagogastroduodenoscopy from July 2011 to October 2014 were prospectively included (N=452). Gastric biopsies were obtained for histology and H. pylori testing. Serum gastrin-17 (G17), pepsinogen (PG) I, PGII and antibodies against H. pylori and cytotoxin-associated gene A protein were determined in all patients. Antibodies against parietal cells and intrinsic factor were determined in patients with advanced (moderate to severe) OGA. Areas under the receiver operating characteristic curves (AUCs) were calculated for serum biomarkers and compared with histology. Overall, 34 patients (8.9%) had advanced OGA by histology (22 women, age 61±15 years). Current or past H. pylori infection and AIG were present in 14/34 and 22/34 patients, respectively. H. pylori-negative AIG patients (N=18) were more likely to have another autoimmune disease (OR 6.3; 95% CI 1.3 to 29.8), severe corpus atrophy (OR 10.1; 95% CI 1.9 to 54.1) and corpus intestinal metaplasia (OR 26.9; 95% CI 5.3 to 136.5) compared with H. pylori-positive patients with advanced OGA. Antrum atrophy was present in 39% of H. pylori-negative AIG patients. The diagnostic performance of G17, PG I and PGI/II was excellent for AIG patients (AUC=0.83, 0.95 and 0.97, respectively), but limited for H. pylori-positive patients with advanced OGA (AUC=0.62, 0.75 and 0.67, respectively). H. pylori-negative AIG has a distinct clinical, morphological and serological phenotype compared with advanced OGA in H. pylori gastritis. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  5. Seronegative Intestinal Villous Atrophy: A Diagnostic Challenge

    Directory of Open Access Journals (Sweden)

    Cláudio Martins

    2016-01-01

    Full Text Available Celiac disease is the most important cause of intestinal villous atrophy. Seronegative intestinal villous atrophy, including those that are nonresponsive to a gluten-free diet, is a diagnostic challenge. In these cases, before establishing the diagnosis of seronegative celiac disease, alternative etiologies of atrophic enteropathy should be considered. Recently, a new clinical entity responsible for seronegative villous atrophy was described—olmesartan-induced sprue-like enteropathy. Herein, we report two uncommon cases of atrophic enteropathy in patients with arterial hypertension under olmesartan, who presented with severe chronic diarrhea and significant involuntary weight loss. Further investigation revealed intestinal villous atrophy and intraepithelial lymphocytosis. Celiac disease and other causes of villous atrophy were ruled out. Drug-induced enteropathy was suspected and clinical improvement and histologic recovery were verified after olmesartan withdrawal. These cases highlight the importance for clinicians to maintain a high index of suspicion for olmesartan as a precipitant of sprue-like enteropathy.

  6. Corpus-Based Word Sense Disambiguation

    CERN Document Server

    Fujii, A

    1998-01-01

    Resolution of lexical ambiguity, commonly termed ``word sense disambiguation'', is expected to improve the analytical accuracy for tasks which are sensitive to lexical semantics. Such tasks include machine translation, information retrieval, parsing, natural language understanding and lexicography. Reflecting the growth in utilization of machine readable texts, word sense disambiguation techniques have been explored variously in the context of corpus-based approaches. Within one corpus-based framework, that is the similarity-based method, systems use a database, in which example sentences are manually annotated with correct word senses. Given an input, systems search the database for the most similar example to the input. The lexical ambiguity of a word contained in the input is resolved by selecting the sense annotation of the retrieved example. In this research, we apply this method of resolution of verbal polysemy, in which the similarity between two examples is computed as the weighted average of the simi...

  7. DEVELOPING AN ONLINE CORPUS OF FORMOSAN LANGUAGES

    Directory of Open Access Journals (Sweden)

    Li-May Sung

    2008-12-01

    Full Text Available Information technologies have now matured to the point of enabling researchers to create a repository of language resources, especially for those languages facing the crisis of endangerment. The development of an online platform of corpora, made possible by recent advances in data storage, character-encoding and web technology, has profound consequences for the accessibility, quantity, quality and interoperability of linguistic field data. This is of particular significance for Formosan languages in Taiwan, many of which are on the verge of extinction. As a response to the recognition of this burgeoning problem, the key objectives of the establishment of the NTU Corpus of Formosan Languages aim to document and thus preserve valuable linguistic data, as well as relevant ethnological and cultural information. This paper will introduce some of the theoretical bases behind this initiative, as well as the procedures, transcription conventions, database normalization, in-house system and three special features in the creation of this corpus.

  8. Bayesian Stratified Sampling to Assess Corpus Utility

    CERN Document Server

    Hochberg, J; Thomas, T; Hall, S; Hochberg, Judith; Scovel, Clint; Thomas, Timothy; Hall, Sam

    1998-01-01

    This paper describes a method for asking statistical questions about a large text corpus. We exemplify the method by addressing the question, "What percentage of Federal Register documents are real documents, of possible interest to a text researcher or analyst?" We estimate an answer to this question by evaluating 200 documents selected from a corpus of 45,820 Federal Register documents. Stratified sampling is used to reduce the sampling uncertainty of the estimate from over 3100 documents to fewer than 1000. The stratification is based on observed characteristics of real documents, while the sampling procedure incorporates a Bayesian version of Neyman allocation. A possible application of the method is to establish baseline statistics used to estimate recall rates for information retrieval systems.

  9. An Automatic Collocation Extraction from Arabic Corpus

    Directory of Open Access Journals (Sweden)

    Abdulgabbar M. Saif

    2011-01-01

    Full Text Available Problem statement: The identification of collocations is very important part in natural language processing applications that require some degree of semantic interpretation such as, machine translation, information retrieval and text summarization. Because of the complexities of Arabic, the collocations undergo some variations such as, morphological, graphical, syntactic variation that constitutes the difficulties of identifying the collocation. Approach: We used the hybrid method for extracting the collocations from Arabic corpus that is based on linguistic information and association measures. Results: This method extracted the bi-gram candidates of Arabic collocation from corpus and evaluated the association measures by using the n-best evaluation method. We reported the precision values for each association measure in each n-best list. Conclusion: The experimental results showed that the log-likelihood ratio is the best association measure that achieved highest precision.

  10. A ROUGH GUIDE TO DOING CORPUS STYLISTICS

    Directory of Open Access Journals (Sweden)

    Tania M. G. Shepherd

    2015-11-01

    Full Text Available This article has two main purposes. The first is to provide a short panorama of existing trends within computer-assisted stylistics. The second is to analyse a prize winning novel by English writer Julian Barnes, by resorting to the tenets and working tools of one of the newest branch of Stylistics, the so-called Corpus stylistics. To this end, the article starts by looking at various attempts at defining what style is and their implications to the definition of the discipline known as Stylistics. Then the paper presents recent work within the field of Corpus stylistics, as it describes the uses of computational tools as part of the stylistician tool kit. Finally, the paper provides a variety of ways with which a literary work may be approached digitally with a view to showing how computational tools can aid the stylistician in acts of interpretation.

  11. Corpus-based Studies on Nursing Textbooks

    Directory of Open Access Journals (Sweden)

    Alif Fairus Nor Mohamad

    2013-07-01

    Full Text Available English for Specific Purposes (ESP educators often face dilemma in deciding what lexical items to teach their students. In the field of English for Nursing Purposes (ENP, there is no exception on this issue as well. Only by analyzing the nursing corpus made up of essential core textbooks that can provide better insights and guide to both nursing students and educators. This research aims to highlight the 2,000 most frequently used nursing words across the core textbooks of nursing and to profile the types of ‘low frequency’ lexis which comprise the nursing corpus in terms of the General Service List (GSL and Academic Word List (AWL lexis coverage. By knowing the frequently used nursing words would further reduce students’ reading deficiency if the students use the 2000-word list.

  12. Classifier Assignment by Corpus-based Approach

    CERN Document Server

    Sornlertlamvanich, V; Meknavin, S; Sornlertlamvanich, Virach; Pantachat, Wantanee; Meknavin, Surapant

    1994-01-01

    This paper presents an algorithm for selecting an appropriate classifier word for a noun. In Thai language, it frequently happens that there is fluctuation in the choice of classifier for a given concrete noun, both from the point of view of the whole spe ech community and individual speakers. Basically, there is no exect rule for classifier selection. As far as we can do in the rule-based approach is to give a default rule to pick up a corresponding classifier of each noun. Registration of classifier for each noun is limited to the type of unit classifier because other types are open due to the meaning of representation. We propose a corpus-based method (Biber, 1993; Nagao, 1993; Smadja, 1993) which generates Noun Classifier Associations (NCA) to overcome the problems in classifier assignment and semantic construction of noun phrase. The NCA is created statistically from a large corpus and recomposed under concept hierarchy constraints and frequency of occurrences.

  13. MR-billeddiagnostik af corpus pineale

    DEFF Research Database (Denmark)

    Langevad, Line; Gøbel Madsen, Camilla; Siebner, Hartwig R.;

    2014-01-01

    Tilgængeligheden af højopløselige MR-teknikker har ført til større opmærksomhed på og nye spørgsmål vedrørende corpus pineales (CP) funktion og kliniske betydning. Dertil kommer en stigende interesse for hormonet melatonins kliniske betydning og relation til forandringer i CP. I denne statusartikel...

  14. USING CORPUS DATA IN RUSSIAN LANGUAGE CLASSROOM

    Directory of Open Access Journals (Sweden)

    A. I. Levinson

    2015-01-01

    Full Text Available Corpora have not yet become an everyday tool of a Russian language teacher in Russia. My goal is to demonstrate a wide range of usagebased approaches which can be applied in the teaching of L1 to children. I present the benefits of exploiting Russian National Corpus as a valuable pedagogical resource, as well as obstacles which can be caused by using data-based teaching methods.

  15. Conditional Sentences: ELT typology and corpus evidence.

    OpenAIRE

    Gabrielatos, Costas

    2003-01-01

    This paper presents the findings of a pilot study examining the representation of the typology of conditional sentences presented in English language teaching (ELT) materials (coursebooks and grammars) in a random sample of 1,000 conditional sentences from the British National Corpus. The if-clause and main clause of the conditional sentences in the sample was annotated for the form of the main verb (particularly tense and aspect), the modal auxiliaries and other lexis expressing modality, ti...

  16. A metaphor corpus in business press headlines

    Directory of Open Access Journals (Sweden)

    Honesto Herrera Soler

    2008-04-01

    Full Text Available In linguistics a corpus typically involves a finite body of texts which are considered to be representative of a particular variety of language at a specific time (McEnery & Wilson, 2001. Those are the assumptions we have had in mind in this metaphor corpus based on business press headlines. Our body of texts is a finite number of headlines drawn from the specific field of the business sections of three newspapers: Financial Times, El País and El Mundo, published over a period running from January to July 2003. Compiling a small corpus of non-literal instantiations as different authors have done (Cortés de los Ríos, 2001; Kövecses, 2002; Charteris-Black, 2003; Koller, 2004; Deignan, 2005; and others will enable us first to identify whether the contextual meaning of a word or a multiword unit of headline contrasts with its basic meaning and whether the contextual meaning can be understood by comparison with that basic meaning, and then to categorize, both in the Spanish and in the British press, the different linguistic realizations of a headline in terms of their syntactic structure, metaphor foci and source domains.

  17. A Corpus-based Approach to Philological Issues

    OpenAIRE

    Boschetti, Federico

    2010-01-01

    The aim of this work is the application of techniques developed in the domain of corpus linguistics to a collection of ancient Greek texts, taking into account not only the canonical text established by modern editors, but also the variant readings recorded in the critical apparatus or in the repertories of conjectures. The dissertation is divided in three connected parts: construction, mapping and analysis of the corpus. The first part is devoted to corpus construction and it is focused ...

  18. The Significance of Self-built Learners’ Written English Corpus

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>Researchers have reached an agreement that corpus exerts an important role in the English teaching and learning,and several learners’ corpus have been established.This paper aims to discuss the necessity and significance of establishing self-built learners’ written English corpus in the hope that teachers and learners will get to know it and use it effectively in their practice.

  19. What is the role of the corpus callosum in intermanual transfer of motor skills? A study of three cases with callosal pathology

    NARCIS (Netherlands)

    Thut, G; Halsband, U; Regard, M; Mayer, E; Leenders, KL; Landis, T

    1997-01-01

    Intermanual transfer for a skilled motor task was studied in two patients with total callosal agenesis, and one with an acquired partial callosal lesion and clinical evidence for disturbed transfer of motor signals. Patients had to draw meaningless figures with one upper extremity (original learning

  20. Neuropsychological performance and corpus callosum abnormalities in adolescents with history of permaturity / Rendimiento neuropsicológico y anormalidades del cuerpo calloso en adolescentes con antecedentes de prematuridad

    OpenAIRE

    Narberhaus, Ana

    2007-01-01

    1. INTRODUCCIÓNLa definición de prematuro es la de recién nacido de edad gestacional inferior a 37 semanas (American Academy of Pediatrics y American College of Obstetrics and Gynecology, 2002). En relación al peso se utilizan con frecuencia las categorías: bajo peso (< 2500g), muy bajo peso (< 1500g) y extremadamente bajo peso (< 1000g) (Picard et al. 2000).En la actualidad, la tasa de partos prematuros en España se sitúa entorno al 8% (Instituto Nacional de Estadística de España: www.se-neo...

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

    Science.gov (United States)

    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…

  2. Quantitative MRI study of progressive cerebral atrophy in multiple system atrophy

    Energy Technology Data Exchange (ETDEWEB)

    Konagaya, Masaaki; Matsuoka, Yukihiko [Suzuka National Hospital, Suzuka, Mie (Japan); Konagaya, Yoko [JR Tokai General Hospital, Nagoya (Japan)

    2002-02-01

    We investigated cerebral atrophy in multiple system atrophy (MSA) by quantitative analysis of MRI. The subjects were 28 patients with MSA (14 striato-nigral degeneration; SND, 14 olivo-ponto-cerebellar atrophy; OPCA. 106 MRI examinations were performed totally) and 85 normal persons for control. The ratios of the ventral pons to the infratentorial space in the sagittal section, the putamen, cerebrum, frontal lobe and parietal and occipital lobes to the intracranial space in the horizontal section, and the temporal lobe to the intracranial space in the coronal section were measured. In the early stage of the disease, OPCA showed significant atrophy of the ventral pons compared with SND, and conversely, SND demonstrated significantly smaller putamen than that in OPCA. According to the progression of the disease, the atrophy of these neural tissues progressed, which resulted in so significant differences between SND and OPCA. The cerebral atrophy was observed in 17 MSA patients. The atrophy of the frontal lobe was much frequent and prominent to that in the temporal lobe and parietal and occipital lobes. SND showed higher incidence of the cerebral atrophy than OPCA in the early stage of the disease. In long period follow-up cases, one case showed cerebral atrophy in earlier stage, and another case in late stage. We indicated the involvement of the cerebral hemispheres in MSA, especially the frontal lobe. (author)

  3. Infraspinatus muscle atrophy from suprascapular nerve compression.

    Science.gov (United States)

    Cordova, Christopher B; Owens, Brett D

    2014-02-01

    Muscle weakness without pain may signal a nerve compression injury. Because these injuries should be identified and treated early to prevent permanent muscle weakness and atrophy, providers should consider suprascapular nerve compression in patients with shoulder muscle weakness.

  4. Mitochondrial signaling contributes to disuse muscle atrophy

    National Research Council Canada - National Science Library

    Powers, Scott K; Wiggs, Michael P; Duarte, Jose A; Zergeroglu, A Murat; Demirel, Haydar A

    2012-01-01

    It is well established that long durations of bed rest, limb immobilization, or reduced activity in respiratory muscles during mechanical ventilation results in skeletal muscle atrophy in humans and other animals...

  5. Corpus & Its Application in Language Teaching

    Institute of Scientific and Technical Information of China (English)

    蔺华国; 王璇

    2004-01-01

    Taking advantage of vast electronic text resources, the corpus-based approach has contributed a lot to linguistic research. It can be applied to almost all areas of investigations in linguistics (Biber, Conrad and Reppen, 1998) . At the same time the role of corpora in the language classroom remains a great controversy. Some linguists believe that corpora are of great help to the language teachers whereas some others hold a negative view on its application to language teaching. As this argument is still under debate , many language teachers are applying corpora to their own teaching and this is the best way to evaluate the adoption of corpora in language classroom.

  6. Two directions of change in one corpus

    DEFF Research Database (Denmark)

    Jensen, Marie Møller

    2015-01-01

    Cheshire et al. (2005) argue that different levels of language do not necessarily follow the same patterns of change over time. In an attempt to test this prediction, this article reports on a comparison between two quantitative corpus studies of Tyneside English which are partly based on the same...... forms. The second study was a study of seven morphosyntactic variables based on data collected in the 1960s, 1994 and 2007-2009. This study found that the variables under investigation were either stable over time or used more frequently in the most recent data. Thus, the comparison of the two studies...... at a time when this area is undergoing vast changes....

  7. Inferring cultural models from corpus data

    DEFF Research Database (Denmark)

    Jensen, Kim Ebensgaard

    2015-01-01

    developed methods of inferring cultural models from observed behavior – in particular observed verbal behavior (including both spoken and written language). While there are plenty of studies of the reflection of cultural models in artificially generated verbal behavior, not much research has been made...... of constructional discursive behavior, the present paper offers a covarying collexeme analysis of the [too ADJ to V]-construction in the Corpus of Contemporary American English. The purpose is to discover the extent to which its force-dynamic constructional semantics interacts with cultural models. We focus...

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

    Science.gov (United States)

    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…

  9. Creating a Live, Public Short Message Service Corpus: The NUS SMS Corpus

    CERN Document Server

    Chen, Tao

    2011-01-01

    Short Message Service (SMS) messages are largely sent directly from one person to another from their mobile phones. They represent a means of personal communication that is an important communicative artifact in our current digital era. As most existing studies have used private access to SMS corpora, comparative studies using the same raw SMS data has not been possible up to now. We describe our efforts to collect a public SMS corpus to address this problem. We use a battery of methodologies to collect the corpus, paying particular attention to privacy issues to address contributors’ concerns. Our live project collects new SMS message submissions, checks their quality and adds the valid messages, releasing the resultant corpus as XML and as SQL dumps, along with corpus statistics, every month. We opportunistically collect as much metadata about the messages and their sender as possible, so as to enable different types of analyses. To date, we have collected about 60,000 messages, focusing on English and...

  10. Hippocampal atrophy rates in Alzheimer disease

    Science.gov (United States)

    Henneman, W J.P.; Sluimer, J D.; Barnes, J; van der Flier, W M.; Sluimer, I C.; Fox, N C.; Scheltens, P; Vrenken, H; Barkhof, F

    2009-01-01

    Objective: To investigate the added value of hippocampal atrophy rates over whole brain volume measurements on MRI in patients with Alzheimer disease (AD), patients with mild cognitive impairment (MCI), and controls. Methods: We included 64 patients with AD (67 ± 9 years; F/M 38/26), 44 patients with MCI (71 ± 6 years; 21/23), and 34 controls (67 ± 9 years; 16/18). Two MR scans were performed (scan interval: 1.8 ± 0.7 years; 1.0 T), using a coronal three-dimensional T1-weighted gradient echo sequence. At follow-up, 3 controls and 23 patients with MCI had progressed to AD. Hippocampi were manually delineated at baseline. Hippocampal atrophy rates were calculated using regional, nonlinear fluid registration. Whole brain baseline volumes and atrophy rates were determined using automated segmentation and registration tools. Results: All MRI measures differed between groups (p < 0.005). For the distinction of MCI from controls, larger effect sizes of hippocampal measures were found compared to whole brain measures. Between MCI and AD, only whole brain atrophy rate differed significantly. Cox proportional hazards models (variables dichotomized by median) showed that within all patients without dementia, hippocampal baseline volume (hazard ratio [HR]: 5.7 [95% confidence interval: 1.5–22.2]), hippocampal atrophy rate (5.2 [1.9–14.3]), and whole brain atrophy rate (2.8 [1.1–7.2]) independently predicted progression to AD; the combination of low hippocampal volume and high atrophy rate yielded a HR of 61.1 (6.1–606.8). Within patients with MCI, only hippocampal baseline volume and atrophy rate predicted progression. Conclusion: Hippocampal measures, especially hippocampal atrophy rate, best discriminate mild cognitive impairment (MCI) from controls. Whole brain atrophy rate discriminates Alzheimer disease (AD) from MCI. Regional measures of hippocampal atrophy are the strongest predictors of progression to AD. GLOSSARY AD = Alzheimer disease; BET = brain

  11. Zika virus causes testicular atrophy

    Science.gov (United States)

    Uraki, Ryuta; Hwang, Jesse; Jurado, Kellie Ann; Householder, Sarah; Yockey, Laura J.; Hastings, Andrew K.; Homer, Robert J.; Iwasaki, Akiko; Fikrig, Erol

    2017-01-01

    Zika virus (ZIKV) is an emerging mosquito-borne flavivirus that has recently been found to cause fetal infection and neonatal abnormalities, including microcephaly and neurological dysfunction. ZIKV persists in the semen months after the acute viremic phase in humans. To further understand the consequences of ZIKV persistence in males, we infected Ifnar1−/− mice via subcutaneous injection of a pathogenic but nonlethal ZIKV strain. ZIKV replication persists within the testes even after clearance from the blood, with interstitial, testosterone-producing Leydig cells supporting virus replication. We found high levels of viral RNA and antigen within the epididymal lumen, where sperm is stored, and within surrounding epithelial cells. Unexpectedly, at 21 days post-infection, the testes of the ZIKV-infected mice were significantly smaller compared to those of mock-infected mice, indicating progressive testicular atrophy. ZIKV infection caused a reduction in serum testosterone, suggesting that male fertility can be affected. Our findings have important implications for nonvector-borne vertical transmission, as well as long-term potential reproductive deficiencies, in ZIKV-infected males. PMID:28261663

  12. Can antioxidants protect against disuse muscle atrophy?

    Science.gov (United States)

    Powers, Scott K

    2014-11-01

    Long periods of skeletal muscle inactivity (e.g. prolonged bed rest or limb immobilization) results in a loss of muscle protein and fibre atrophy. This disuse-induced muscle atrophy is due to both a decrease in protein synthesis and increased protein breakdown. Although numerous factors contribute to the regulation of the rates of protein breakdown and synthesis in skeletal muscle, it has been established that prolonged muscle inactivity results in increased radical production in the inactive muscle fibres. Further, this increase in radical production plays an important role in the regulation of redox-sensitive signalling pathways that regulate both protein synthesis and proteolysis in skeletal muscle. Indeed, it was suggested over 20 years ago that antioxidant supplementation has the potential to protect skeletal muscles against inactivity-induced fibre atrophy. Since this original proposal, experimental evidence has implied that a few compounds with antioxidant properties are capable of delaying inactivity-induced muscle atrophy. The objective of this review is to discuss the role that radicals play in the regulation of inactivity-induced skeletal muscle atrophy and to provide an analysis of the recent literature indicating that specific antioxidants have the potential to defer disuse muscle atrophy.

  13. Named Entity Recognition Using Web Document Corpus

    CERN Document Server

    Karaa, Wahiba Ben Abdessalem

    2011-01-01

    This paper introduces a named entity recognition approach in textual corpus. This Named Entity (NE) can be a named: location, person, organization, date, time, etc., characterized by instances. A NE is found in texts accompanied by contexts: words that are left or right of the NE. The work mainly aims at identifying contexts inducing the NE's nature. As such, The occurrence of the word "President" in a text, means that this word or context may be followed by the name of a president as President "Obama". Likewise, a word preceded by the string "footballer" induces that this is the name of a footballer. NE recognition may be viewed as a classification method, where every word is assigned to a NE class, regarding the context. The aim of this study is then to identify and classify the contexts that are most relevant to recognize a NE, those which are frequently found with the NE. A learning approach using training corpus: web documents, constructed from learning examples is then suggested. Frequency representatio...

  14. Temporal Expressions in Polish Corpus KPWr

    Directory of Open Access Journals (Sweden)

    Jan Kocoń

    2015-12-01

    Full Text Available Temporal Expressions in Polish Corpus KPWr This article presents the result of the recent research in the interpretation of Polish expressions that refer to time. These expressions are the source of information when something happens, how often something occurs or how long something lasts. Temporal information, which can be extracted from text automatically, plays significant role in many information extraction systems, such as question answering, discourse analysis, event recognition and many more. We prepared PLIMEX — a broad description of Polish temporal expressions with annotation guidelines, based on the state-of-the-art solutions for English, mainly TimeML specification. We also adapted the solution to capture the local semantics of temporal expressions, called LTIMEX. Temporal description also supports further event identification and extends event description model, focusing at anchoring events in time, ordering events and reasoning about the persistence of events. We prepared the specification, which is designed to address these issues and we annotated all documents in Polish Corpus of Wroclaw University of Technology (KPWr using our annotation guidelines.

  15. Towards an event annotated corpus of Polish

    Directory of Open Access Journals (Sweden)

    Michał Marcińczuk

    2015-12-01

    Full Text Available Towards an event annotated corpus of Polish The paper presents a typology of events built on the basis of TimeML specification adapted to Polish language. Some changes were introduced to the definition of the event categories and a motivation for event categorization was formulated. The event annotation task is presented on two levels – ontology level (language independent and text mentions (language dependant. The various types of event mentions in Polish text are discussed. A procedure for annotation of event mentions in Polish texts is presented and evaluated. In the evaluation a randomly selected set of documents from the Corpus of Wrocław University of Technology (called KPWr was annotated by two linguists and the annotator agreement was calculated. The evaluation was done in two iterations. After the first evaluation we revised and improved the annotation procedure. The second evaluation showed a significant improvement of the agreement between annotators. The current work was focused on annotation and categorisation of event mentions in text. The future work will be focused on description of event with a set of attributes, arguments and relations.

  16. Linguistics, Sociolinguistics, and Corpus Linguistics: Ideal Language Versus Real Language.

    Science.gov (United States)

    De Beaugrande, Robert

    1999-01-01

    Highlights modes of evidence in large corpus research that may be significant for Sociolinguistics. Suggests that corpus data can help Sociolinguistics engage with issues and variations in usage that are less abstract then phonetics, phonology, and grammar but more proximate to the socially vital issues of the 20th century. (Author/VWL)

  17. The Analysis of The Happy Prince Based on Corpus

    Institute of Scientific and Technical Information of China (English)

    LI Hui

    2014-01-01

    As a new and rising discipline, Corpus Linguistics can be applied in the field of literary criticism to analyze literary text. Analyzing“The Happy Prince”written by the famous British writer Oscar Wilde with corpus can help reveal how the plot, por-traits of people and the rhetorical devices express the theme of the story.

  18. Corpus-based Study on English Synonym Discrimination

    Institute of Scientific and Technical Information of China (English)

    贺倩静

    2014-01-01

    Corpus is widely used with the rapid development of corpus technology.This paper mainly introduces cor-pus-based study on English synonym discrimination which is effective in grasping English near synonyms. This cor-pus-based study may also give some implications on English learning.

  19. DutchParl: A corpus of parliamentary documents in Dutch

    NARCIS (Netherlands)

    Marx, M.; Schuth, A.; Calzolari, N.; Choukri, K.; Maegaard, B.; Mariani, J.; Odijk, J.; Piperidis, S.; Rosner, M.; Tapias, D.

    2010-01-01

    A corpus called DutchParl is created which aims to contain all digitally available parliamentary documents written in the Dutch language. The first version of DutchParl contains documents from the parliaments of The Netherlands, Flanders and Belgium. The corpus is divided along three dimensions: per

  20. TwNC: a Multifaceted Dutch News Corpus

    NARCIS (Netherlands)

    Ordelman, Roeland; Jong, de Franciska; Hessen, van Arjan; Hondorp, Hendri

    2007-01-01

    This contribution describes the Twente News Corpus (TwNC), a multifaceted corpus for Dutch that is being deployed in a number of NLP research projects among which tracks within the Dutch national research programme MultimediaN, the NWO programme CATCH, and the Dutch-Flemish programme STEVIN. The de

  1. Linguistics, Sociolinguistics, and Corpus Linguistics: Ideal Language Versus Real Language.

    Science.gov (United States)

    De Beaugrande, Robert

    1999-01-01

    Highlights modes of evidence in large corpus research that may be significant for Sociolinguistics. Suggests that corpus data can help Sociolinguistics engage with issues and variations in usage that are less abstract then phonetics, phonology, and grammar but more proximate to the socially vital issues of the 20th century. (Author/VWL)

  2. Designing a Corpus for Translation and Language Teaching.

    Science.gov (United States)

    Bernardini, Silvia

    2003-01-01

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

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

    Science.gov (United States)

    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,…

  4. Developing Corpus-Based Materials to Teach Pragmatic Routines

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  6. Developing Corpus-Based Materials to Teach Pragmatic Routines

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  8. Global brain atrophy but not hippocampal atrophy is related to type 2 diabetes

    NARCIS (Netherlands)

    Wisse, L.E.; Bresser, J. de; Geerlings, M.I.; Reijmer, Y.D.; Portegies, M.L.; Brundel, M.; Kappelle, L.J.; Graaf, Y. van der; Biessels, G.J.; Kessels, R.P.C.

    2014-01-01

    AIMS: It has been suggested that in patients with type 2 diabetes mellitus (T2DM), brain atrophy is most pronounced in the hippocampus, but this has not been investigated systematically. The present pooled analysis of three studies examined if hippocampal atrophy is more prominent than global brain

  9. Can endoscopic atrophy predict histological atrophy? Historical study in United Kingdom and Japan.

    Science.gov (United States)

    Kono, Shin; Gotoda, Takuji; Yoshida, Shigeaki; Oda, Ichiro; Kondo, Hitoshi; Gatta, Luigi; Naylor, Greg; Dixon, Michael; Moriyasu, Fuminori; Axon, Anthony

    2015-12-14

    To assess the diagnostic concordance between endoscopic and histological atrophy in the United Kingdom and Japan. Using published data, a total of 252 patients, 126 in the United Kingdom and 126 in Japan, aged 20 to 80 years, were evaluated. The extent of endoscopic atrophy was classified into five subgroups according to a modified Kimura-Takemoto classification system and was compared with histological findings of atrophy at five biopsy sites according to the updated Sydney system. The strength of agreement of the extent of atrophy between histology and visual endoscopic inspection showed good reproducibility, with a weighted kappa value of 0.76 (P atrophy (OR = 0.10, 95%CI: 0.03-0.36). The strength of agreement between endoscopic and histological atrophy, assessed by cancer risk-oriented grading, was reproducible, with a kappa value of 0.81 (95%CI: 0.75-0.87). Only nine patients (3.6%) were endoscopically underdiagnosed with antral predominant rather than extensive atrophy and were considered false negatives. Endoscopic grading can predict histological atrophy with few false negatives, indicating that precancerous conditions can be identified during screening endoscopy, particularly in patients in western countries.

  10. Correlation of Brain Atrophy, Disability, and Spinal Cord Atrophy in a Murine Model of Multiple Sclerosis.

    Science.gov (United States)

    Paz Soldán, M Mateo; Raman, Mekala R; Gamez, Jeffrey D; Lohrey, Anne K; Chen, Yi; Pirko, Istvan; Johnson, Aaron J

    2015-01-01

    Disability progression in multiple sclerosis (MS) remains incompletely understood. Unlike lesional measures, central nervous system atrophy has a strong correlation with disability. Theiler's murine encephalomyelitis virus infection in SJL/J mice is an established model of progressive MS. We utilized in vivo MRI to quantify brain and spinal cord atrophy in this model and analyzed the temporal relationship between atrophy and disability. Infected and control mice were followed for 12 months. Disability was assessed periodically using rotarod assay. Volumetric MRI datasets were acquired at 7 Tesla. Ventricular volume and C4-5 spinal cord cross-sectional area measurements were performed using Analyze 10. At 3 months, brain atrophy reached statistical significance (P = .005). In contrast, disability did not differ until 4 months post-infection (P = .0005). Cord atrophy reached significance by 9 months (P = 0.009). By 12 months, brain atrophy resulted in 111.8% increased ventricular volume (P = .00003), while spinal cord cross-sectional area was 25.6% reduced (P = .001) among cases. Our results suggest that significant brain atrophy precedes and predicts the development of disability, while spinal cord atrophy occurs late and correlates with severe disability. The observed temporal relationship establishes a framework for mechanisms of disability progression and enables further investigations of their underlying substrate. Copyright © 2015 by the American Society of Neuroimaging.

  11. Building a semantically annotated corpus of clinical texts.

    Science.gov (United States)

    Roberts, Angus; Gaizauskas, Robert; Hepple, Mark; Demetriou, George; Guo, Yikun; Roberts, Ian; Setzer, Andrea

    2009-10-01

    In this paper, we describe the construction of a semantically annotated corpus of clinical texts for use in the development and evaluation of systems for automatically extracting clinically significant information from the textual component of patient records. The paper details the sampling of textual material from a collection of 20,000 cancer patient records, the development of a semantic annotation scheme, the annotation methodology, the distribution of annotations in the final corpus, and the use of the corpus for development of an adaptive information extraction system. The resulting corpus is the most richly semantically annotated resource for clinical text processing built to date, whose value has been demonstrated through its use in developing an effective information extraction system. The detailed presentation of our corpus construction and annotation methodology will be of value to others seeking to build high-quality semantically annotated corpora in biomedical domains.

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

    Science.gov (United States)

    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).

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

    Science.gov (United States)

    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)…

  14. Consultation de corpus et styles d’apprentissage Corpus consultation and learning styles

    OpenAIRE

    Alex Boulton

    2012-01-01

    Les corpus représentent une ressource avec de multiples possibilités pour l’apprentissage des langues, mais les résultats d’expériences avec les étudiants sont moins convaincants qu’on pourrait l’espérer. Une explication serait que les résultats quantitatifs cachent la diversité des profils d’apprenants. Cette étude décrit une expérience où des étudiants en architecture consultent soit un corpus, soit un dictionnaire pour résoudre des difficultés précises d’usage en anglais, et complètent un ...

  15. No relevant midbrain atrophy in Parkinson's disease.

    Science.gov (United States)

    Mäkinen, E; Joutsa, J; Isotalo, J; Kaasinen, V

    2016-11-01

    To investigate whether significant midbrain atrophy is present in Parkinson's disease (PD), and if so, whether it can be used as a marker of striatal dopaminergic degeneration. In total, 150 PD patients and 155 controls were scanned with both brain dopamine transporter (DAT) [(123) I]FP-CIT SPECT and 1.5T MRI. Midbrain atrophy was measured from sagittal MRIs using the midbrain-to-pons ratios. Both striatal region-of-interest-based (Brass) and striatal and extrastriatal voxel-by-voxel-based DAT binding (SPM8) were investigated in relation to midbrain atrophy. The midbrain-to-pons ratios in PD patients were slightly lower than those in the controls (mean 0.59 vs 0.61, P atrophy is present in PD and can be detected with MRI. However, the midbrain atrophy in PD is not associated with the level of striatal dopaminergic dysfunction, and midbrain measurements therefore cannot be used as a clinically useful predictor of dopamine function. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Subluxation and semantics: a corpus linguistics study.

    Science.gov (United States)

    Budgell, Brian

    2016-06-01

    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. 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.' 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. 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.

  17. Newly developed vaginal atrophy symptoms II and vaginal pH: a better correlation in vaginal atrophy?

    Science.gov (United States)

    Tuntiviriyapun, P; Panyakhamlerd, K; Triratanachat, S; Chatsuwan, T; Chaikittisilpa, S; Jaisamrarn, U; Taechakraichana, N

    2015-04-01

    The primary objective of this study was to evaluate the correlation among symptoms, signs, and the number of lactobacilli in postmenopausal vaginal atrophy. The secondary objective was to develop a new parameter to improve the correlation. A cross-sectional descriptive study. Naturally postmenopausal women aged 45-70 years with at least one clinical symptom of vaginal atrophy of moderate to severe intensity were included in this study. All of the objective parameters (vaginal atrophy score, vaginal pH, the number of lactobacilli, vaginal maturation index, and vaginal maturation value) were evaluated and correlated with vaginal atrophy symptoms. A new parameter of vaginal atrophy, vaginal atrophy symptoms II, was developed and consists of the two most bothersome symptoms (vaginal dryness and dyspareunia). Vaginal atrophy symptoms II was analyzed for correlation with the objective parameters. A total of 132 naturally postmenopausal women were recruited for analysis. Vaginal pH was the only objective parameter found to have a weak correlation with vaginal atrophy symptoms (r = 0.273, p = 0.002). The newly developed vaginal atrophy symptoms II parameter showed moderate correlation with vaginal pH (r = 0.356, p atrophy score (r = 0.230, p atrophy symptoms and the objective parameters. Vaginal pH was significantly correlated with vaginal atrophy symptoms. The newly developed vaginal atrophy symptoms II was associated with a better correlation. The vaginal atrophy symptoms II and vaginal pH may be better tools for clinical evaluation and future study of the vaginal ecosystem.

  18. Metaphor and Corpus Linguistics Metáfora e linguística de corpus

    Directory of Open Access Journals (Sweden)

    Tony Berber Sardinha

    2011-01-01

    Full Text Available In this paper, I look at four different aspects of metaphor research from a corpus linguistic perspective, namely: (1 the lexicogrammar of metaphors, which refers to the patterning of linguistic metaphor revealed by corpus analysis; (2 metaphor probabilities, which is a facet of metaphor that emerges from frequency-based studies of metaphor; (3 dimensions of metaphor variation, or the search for systematic parameters of variation in metaphor use across different registers; and (4 automated metaphor retrieval, which relates to the development of software to help identify metaphors in corpora. I argue that these four aspects are interrelated, and that advances in one of them can drive changes in the others.Neste artigo discuto quarto aspectos da pesquisa sobre metáfora do ponto de vista da linguística de corpus: (1 a lexicogramática das metáforas, que se refere aos padrões da metáfora linguística revelados pela análise de corpus; (2 probabilidades metafóricas, que é uma faceta da metáfora que emerge a partir dos estudos relacionados à freqüência de metáforas; (3 dimensões da variação de metáforas, ou a busca por parâmetros sistemáticos de variação de uso de metáfora em diferentes gêneros; e (4 captura automática de metáfora, que está relacionada ao desenvolvimento de softwares que auxiliam na identificação de metáforas em corpora. I defendo que esses quatro aspectos são interrelacionados, e que progressos em um deles podem acarretar mudanças nos outros.

  19. Corpus-Based Word Sense Disambiguation

    Science.gov (United States)

    Fujii, Atsushi

    1998-04-01

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

  20. From Business Corpus to Business Lexicon*

    Directory of Open Access Journals (Sweden)

    Li Lan

    2011-10-01

    Full Text Available

    Abstract: Language corpora are now indispensable to dictionary compilation. They help broaden the role of the dictionary from standardizing the vocabulary to recording a language. The trilingual corpus generated by the Hong Kong Polytechnic University gives a record of business languages used in Hong Kong. It differs from other corpora in that (1 it includes English, Chinese and Japanese; (2 it shows local characteristics; and (3 it focuses on a specific area (financial services, including banking, accounting, auditing, insurance and investment. The paper discusses various issues of setting up a tricorpus, and how to make full use of the data to generate a trilingual lexicon.

    Keywords: MULTILINGUAL, SPECIAL PURPOSE, CORPUS, LEXICON

    Opsomming: Van sakekorpus tot sakeleksikon. Taalkorpora is tans onontbeerlik virdie samestelling van woordeboeke. Hulle help om die rol van die woordeboek uit te brei vanaf diestandaardisering van die woordeskat tot die optekening van ‘n taal. Die drietalige korpus wat deurdie Hongkongse Politegniese Universiteit ontwikkel is, verskaf ‘n opgawe van die saketale wat inHongkong gebruik word. Dit verskil van ander korpora deurdat (1 dit Engels, Chinees and Japaneesinsluit; (2 dit plaaslike eienskappe vertoon; en (3 dit op 'n spesifieke gebied (finansiële dienste,insluitende bankwese, rekeningkunde, ouditering, versekering en belegging fokus. Die artikelbespreek verskillende aspekte van die totstandbrenging van 'n drietalige korpus, en hoe om vollegebruik te maak van die data om 'n drietalige leksikon te genereer.

    Sleutelwoorde: MEERTALIG, SPESIALE DOEL, KORPUS, LEKSIKON

  1. Cardiac Atrophy and Heart Failure In Cancer.

    Science.gov (United States)

    Sweeney, Mark; Yiu, Angela; Lyon, Alexander R

    2017-04-01

    Functional changes in the heart in patients with cancer can be a result of both the disease itself and various cancer therapies, and limiting cardiac damage has become an increasingly important issue as survival rates in patients with cancer have improved. Processes involved in cancer-induced cardiac atrophy may include cardiomyocyte atrophy and apoptosis, decreased protein synthesis, increased autophagy and proteolysis via the ubiquitin-proteosome system. Further to direct effects of malignancy on the heart, several chemotherapeutic agents are known to affect the myocardium, in particular the anthracyclines. The aim of this report is to review the effects of cancer and cancer treatment on the heart and what is known about the underlying mechanisms. Furthermore, clinical strategies to limit and treat cancer-associated cardiac atrophy are discussed, emphasising the benefit of a multidisciplinary approach by cardiologists and oncologists to optimise models of care to improve outcomes for patients with cancer.

  2. Does gastric atrophy exist in children?

    Institute of Scientific and Technical Information of China (English)

    Georges Dimitrov; Frédéric Gottrand

    2006-01-01

    Several clinical reports confirmed that gastric atrophy is a pathology not only limited to adult patients. In pediatrics, it is most often described in association with a Hpylori infection but this bacteria does not seem to be the only etiological factor of this preneoplastic state in children. The frequency of gastric atrophy and intestinal metaplasia in children are unknown because they are not systematically sought during upper gastrointestinal endoscopy. The lack of specific histological classification of children's gastropathies makes their diagnosis difficult for pathologists. Based on our knowledge to date, we think that it is necessary to describe, in detail, the natural course of this lesion during childhood. A close and prolonged clinical and endoscopic follow-up is important for children with gastric atrophy.

  3. Differential induction of muscle atrophy pathways in two mouse models of spinal muscular atrophy

    Science.gov (United States)

    Deguise, Marc-Olivier; Boyer, Justin G.; McFall, Emily R.; Yazdani, Armin; De Repentigny, Yves; Kothary, Rashmi

    2016-01-01

    Motor neuron loss and neurogenic atrophy are hallmarks of spinal muscular atrophy (SMA), a leading genetic cause of infant deaths. Previous studies have focused on deciphering disease pathogenesis in motor neurons. However, a systematic evaluation of atrophy pathways in muscles is lacking. Here, we show that these pathways are differentially activated depending on severity of disease in two different SMA model mice. Although proteasomal degradation is induced in skeletal muscle of both models, autophagosomal degradation is present only in Smn2B/− mice but not in the more severe Smn−/−; SMN2 mice. Expression of FoxO transcription factors, which regulate both proteasomal and autophagosomal degradation, is elevated in Smn2B/− muscle. Remarkably, administration of trichostatin A reversed all molecular changes associated with atrophy. Cardiac muscle also exhibits differential induction of atrophy between Smn2B/− and Smn−/−; SMN2 mice, albeit in the opposite direction to that of skeletal muscle. Altogether, our work highlights the importance of cautious analysis of different mouse models of SMA as distinct patterns of atrophy induction are at play depending on disease severity. We also revealed that one of the beneficial impacts of trichostatin A on SMA model mice is via attenuation of muscle atrophy through reduction of FoxO expression to normal levels. PMID:27349908

  4. Geographic atrophy phenotype identification by cluster analysis.

    Science.gov (United States)

    Monés, Jordi; Biarnés, Marc

    2017-07-20

    To identify ocular phenotypes in patients with geographic atrophy secondary to age-related macular degeneration (GA) using a data-driven cluster analysis. This was a retrospective analysis of data from a prospective, natural history study of patients with GA who were followed for ≥6 months. Cluster analysis was used to identify subgroups within the population based on the presence of several phenotypic features: soft drusen, reticular pseudodrusen (RPD), primary foveal atrophy, increased fundus autofluorescence (FAF), greyish FAF appearance and subfoveal choroidal thickness (SFCT). A comparison of features between the subgroups was conducted, and a qualitative description of the new phenotypes was proposed. The atrophy growth rate between phenotypes was then compared. Data were analysed from 77 eyes of 77 patients with GA. Cluster analysis identified three groups: phenotype 1 was characterised by high soft drusen load, foveal atrophy and slow growth; phenotype 3 showed high RPD load, extrafoveal and greyish FAF appearance and thin SFCT; the characteristics of phenotype 2 were midway between phenotypes 1 and 3. Phenotypes differed in all measured features (p≤0.013), with decreases in the presence of soft drusen, foveal atrophy and SFCT seen from phenotypes 1 to 3 and corresponding increases in high RPD load, high FAF and greyish FAF appearance. Atrophy growth rate differed between phenotypes 1, 2 and 3 (0.63, 1.91 and 1.73 mm(2)/year, respectively, p=0.0005). Cluster analysis identified three distinct phenotypes in GA. One of them showed a particularly slow growth pattern. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  5. Corpus Linguistics and the Design of a Response Message

    Science.gov (United States)

    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

  6. Holistic corpus-based dialectology Dialetologia holística baseada em corpus

    Directory of Open Access Journals (Sweden)

    Benedikt Szmrecsanyi

    2011-01-01

    Full Text Available This paper is concerned with sketching future directions for corpus-based dialectology. We advocate a holistic approach to the study of geographically conditioned linguistic variability, and we present a suitable methodology, 'corpusbased dialectometry', in exactly this spirit. Specifically, we argue that in order to live up to the potential of the corpus-based method, practitioners need to (i abandon their exclusive focus on individual linguistic features in favor of the study of feature aggregates, (ii draw on computationally advanced multivariate analysis techniques (such as multidimensional scaling, cluster analysis, and principal component analysis, and (iii aid interpretation of empirical results by marshalling state-of-the-art data visualization techniques. To exemplify this line of analysis, we present a case study which explores joint frequency variability of 57 morphosyntax features in 34 dialects all over Great Britain.Este artigo debruça-se sobre o esboço propositivo de futuras direções para a dialetologia baseada em corpus. Defendemos uma abordagem holística para o estudo da variabilidade linguística geograficamente condicionada, e apresentamos uma metodologia adequada para tal - a dialetometria baseada em corpus. Mais especificamente, defendemos que para que se obtenham todos os resultados esperados da metodologia de corpus, pesquisadores devem: (i abandonar seu foco exclusivo em traços linguísticos individuais em favor do estudo dos agregados de traços, (ii amparar-se em métodos computacionais avançados de técnicas de análise multivariada (tais como escalagem multidimensional, análise de clusters, e análise de componente principal, e (iii auxiliar a interpretação de resultados empíricos através da utilização do estado da arte em técnicas de visualização. A fim de exemplificarmos essa linha de análise, apresentamos um estudo de caso que explora a variabilidade da frequência agregada de 57 tra

  7. Dissemineret sklerose

    DEFF Research Database (Denmark)

    Stenager, E; Knudsen, L; Jensen, K

    1991-01-01

    The MRI-(magnetic resonance imaging) scanner has improved the knowledge of the organic basis of cognitive defects in multiple sclerosis. Recent studies demonstrated a correlation of MRI-verified single lesions, atrophy of the corpus callosum and cognitive defects; but failed to demonstrate...

  8. Restless legs syndrome in multiple system atrophy.

    Science.gov (United States)

    Ghorayeb, Imad; Dupouy, Sandrine; Tison, François; Meissner, Wassilios G

    2014-12-01

    The purpose of the study was to evaluate the frequency of restless legs syndrome in 30 patients with multiple system atrophy. Eight patients complained from restless legs syndrome, their severity score was 19.4 ± 4.1. Pittsburgh Sleep Quality Index scores were significantly higher in patients with restless legs syndrome than those without (9.3 ± 3.7 vs. 4.8 ± 2.9, p = 0.00165). Periodic limb movements were found in 75% of patients with restless legs syndrome. Restless legs syndrome is more prevalent in multiple system atrophy as compared to the acknowledged prevalence in the general population.

  9. Progressive cerebral atrophy in neuromyelitis optica.

    Science.gov (United States)

    Warabi, Yoko; Takahashi, Toshiyuki; Isozaki, Eiji

    2015-12-01

    We report two cases of neuromyelitis optica patients with progressive cerebral atrophy. The patients exhibited characteristic clinical features, including elderly onset, secondary progressive tetraparesis and cognitive impairment, abnormally elevated CSF protein and myelin basic protein levels, and extremely highly elevated serum anti-AQP-4 antibody titer. Because neuromyelitis optica pathology cannot switch from an inflammatory phase to the degenerative phase until the terminal phase, neuromyelitis optica rarely appears as a secondary progressive clinical course caused by axonal degeneration. However, severe intrathecal inflammation and massive destruction of neuroglia could cause a secondary progressive clinical course associated with cerebral atrophy in neuromyelitis optica patients.

  10. Mirror movements in progressive hemifacial atrophy

    Science.gov (United States)

    Verma, Rajesh; Dixit, Puneet Kumar; Lalla, Rakesh; Singh, Babita

    2015-01-01

    Mirror movements are simultaneous, involuntary, identical movements occurring during contralateral voluntary movements. These movements are considered as soft neurologic signs seen uncommonly in clinical practice. The mirror movements are described in various neurological disorders which include parkinsonism, cranio veretebral junction anamolies, and hemiplegic cerebral palsy. These movements are intriguing and can pose significant disability. However, no such observation regarding mirror movements in progressive hemifacial atrophy have been reported previously. We are reporting a teenage girl suffering from progressive hemifacial atrophy and epilepsy with demonstrable mirror movements in hand. PMID:26019431

  11. Mirror movements in progressive hemifacial atrophy

    Directory of Open Access Journals (Sweden)

    Rajesh Verma

    2015-01-01

    Full Text Available Mirror movements are simultaneous, involuntary, identical movements occurring during contralateral voluntary movements. These movements are considered as soft neurologic signs seen uncommonly in clinical practice. The mirror movements are described in various neurological disorders which include parkinsonism, cranio veretebral junction anamolies, and hemiplegic cerebral palsy. These movements are intriguing and can pose significant disability. However, no such observation regarding mirror movements in progressive hemifacial atrophy have been reported previously. We are reporting a teenage girl suffering from progressive hemifacial atrophy and epilepsy with demonstrable mirror movements in hand.

  12. Posterior cortical atrophy: a brief review.

    Science.gov (United States)

    Kirshner, Howard S; Lavin, Patrick J M

    2006-11-01

    Posterior cortical atrophy is a striking clinical syndrome in which a dementing illness begins with visual symptoms. Initially, the problem may seem to be loss of elementary vision, but over time the patient develops features of visual agnosia, topographical difficulty, optic ataxia, simultanagnosia, ocular apraxia (Balint's syndrome), alexia, acalculia, right-left confusion, and agraphia (Gerstmann's syndrome), and later a more generalized dementia. Occasional patients have visual hallucinations and signs of Parkinson's disease or Lewy body dementia. A number of different neuropathologic disorders are associated with posterior cortical atrophy.

  13. Genetics Home Reference: spinal muscular atrophy with progressive myoclonic epilepsy

    Science.gov (United States)

    ... Spinal muscular atrophy with progressive myoclonic epilepsy (SMA-PME) is a neurological condition that causes muscle weakness ... muscle jerks (myoclonic epilepsy). In individuals with SMA-PME, spinal muscular atrophy results from a loss of ...

  14. FTA Corpus: a parallel corpus of English and Spanish Free Trade Agreements for the study of specialized collocations

    Directory of Open Access Journals (Sweden)

    Pedro Patiño García

    2013-04-01

    Full Text Available This paper describes the Corpus of Free Trade Agreements (henceforth FTA, a specialized parallel corpus in English and Spanish from Europe and America and a smaller subcorpus in English-Norwegian and Spanish-Norwegian that was prepared and then aligned with Translation Corpus Aligner 2 (Hofland & Johansson, 1998. The data was taken from Free Trade Agreements. These agreements are specialized texts officially signed and ratified by several countries and blocks of countries in the last twenty years. Thus, FTAs are a rich repository for terminology and phraseology that is used in different fields of business activity throughout the world. The corpus contains around 1.37 million words in the English section and 1.48 million words in its Spanish counterpart, plus 60,000 words each in the Spanish-Norwegian and English-Norwegian subcorpus. The corpus is being used primarily to study the terms and specialized collocations that include these terms in this kind of specialized texts.Keywords: specialized collocation, specialized parallel corpus, corpus linguistics, Free Trade Agreement

  15. Application of multilingual corpus in contrastive studies (on the example of the Bulgarian-Polish-Lithuanian parallel corpus

    Directory of Open Access Journals (Sweden)

    Ludmila Dimitrova

    2015-11-01

    Full Text Available Application of multilingual corpus in contrastive studies (on the example of the Bulgarian-Polish-Lithuanian parallel corpus In this paper we present applications of a trilingual corpus in language research. Comparative and contrastive studies of Polish and Bulgarian as well as Polish and Lithuanian have been already conducted, but up to the best of our knowledge no such studies exist for Bulgarian and Lithuanian. On the one hand, it is interesting to note that two Slavic languages are compared to a Baltic language (Lithuanian. On the other hand, the three languages are marginally present in the EU because of the later ascension of the three countries to the EU. The paper shortly describes the first electronic Bulgarian–Polish–Lithuanian experimental corpus, currently under development only for research. We also focus our attention on the morphosyntactic annotation of the parallel trilingual corpus according to the Corpus Encoding Standard: we present a review of the Part-of-Speech (POS classification of the participle in the three languages – Bulgarian, Polish, and Lithuanian in comparison to another POS, the adjective. We briefly discuss tagsets for corpus annotation from the point of view of possible unification in the future with some examples.

  16. Grey matter atrophy in patients suffering from multiple sclerosis.

    Science.gov (United States)

    Kincses, Zsigmond Tamás; Tóth, Eszter; Bankó, Nóra; Veréb, Dániel; Szabó, Nikoletta; Csete, Gergő; Faragó, Péter; Király, András; Bencsik, Krisztina; Vécsei, László

    2014-09-30

    White matter lesions are defining characteristics of multiple sclerosis (MS), whereas grey matter involvement is a less recognised attribute. Recent investigations using dedicated imaging approaches have made it possible to depict cortical lesions. Additionally, grey matter atrophy may be estimated using various methods. Several studies have suggested that grey matter atrophy closely correlates to clinical disability. In this review we have collected information on grey matter atrophy in MS and the effect of disease modifying therapies upon brain atrophy.

  17. New Advances in Corpus-based Lexicography*

    Directory of Open Access Journals (Sweden)

    Arvi Hurskainen

    2011-10-01

    Full Text Available

    Abstract: This article presents various approaches used in corpus-based computational lexico-graphy. A claim is made that in order for computational lexicography to be efficient, precise and comprehensive, it should utilize the method where the corpus text is first analysed, and the results of this analysis is then processed further to meet the needs of a dictionary. This method has several advantages, including high precision and recall, as well as the possibility to automate the process much further than with more traditional computational methods. The frequency list obtained by using the lemma (the equivalent of the headword as basis helps in selecting the words to be in-cluded in the dictionary. The approach is demonstrated through various phases by applying SALAMA (the Swahili Language Manager to the process. Manual work will be needed in the phase when examples of use are selected from the corpus, and possibly modified. However, the list of examples of use, arranged alphabetically according to the corresponding headword, can also be produced automatically. Thus the alphabetical list of headwords with examples of use is the mate-rial on which the lexicographer works manually. The article deals with problems encountered in compiling traditional printed dictionaries, and it excludes electronic dictionaries and thesauri.

    Keywords: LEXICOGRAPHY, DICTIONARY, LANGUAGE TECHNOLOGY, COMPUTA-TIONAL LINGUISTICS, AUTOMATIC COMPILATION, DICTIONARY TESTING, INFORMA-TION RETRIEVAL, MORPHOLOGICAL ANALYSIS, SEMANTIC ANALYSIS, DISAMBIGUA-TION, HEURISTICS

    Opsomming: Nuwe ontwikkelinge in korpusgebaseerde leksikografie. Hier-die artikel beskryf verskillende benaderings wat in korpusgebaseerde rekenaarleksikografie ge-bruik word. Daar word aangevoer dat vir rekenaarleksikografie om doelmatig, noukeurig en omvattend te wees, dit die metode behoort te gebruik waarby die korpusteks eers ontleed word, en die resultaat van hierdie ontleding dan verder

  18. An unusual cause of optic atrophy in a child

    Directory of Open Access Journals (Sweden)

    Nishant Kumar

    2014-01-01

    Full Text Available A 13-year-old child presenting with gross visual impairment was diagnosed as a case of optic atrophy. However, radiological investigations revealed osteopetrosis, which, though rare, can result in optic atrophy. The aim of this case report is to highlight this possibility while evaluating cases of optic atrophy in young patients.

  19. A Corpus-based Discourse Analysis on Barack Obama’s Weekly Addresses

    Institute of Scientific and Technical Information of China (English)

    陈凯丽

    2015-01-01

    With the development and application of computational corpus, corpus linguistics has made great development. The daily life has seen the application and significance of corpus. Especialy in teaching for it can not only supply textbooks directly but also plays a large role in the outline of textbook and composition correction. Hence, corpus is widely applied.

  20. Redox control of skeletal muscle atrophy.

    Science.gov (United States)

    Powers, Scott K; Morton, Aaron B; Ahn, Bumsoo; Smuder, Ashley J

    2016-09-01

    Skeletal muscles comprise the largest organ system in the body and play an essential role in body movement, breathing, and glucose homeostasis. Skeletal muscle is also an important endocrine organ that contributes to the health of numerous body organs. Therefore, maintaining healthy skeletal muscles is important to support overall health of the body. Prolonged periods of muscle inactivity (e.g., bed rest or limb immobilization) or chronic inflammatory diseases (i.e., cancer, kidney failure, etc.) result in skeletal muscle atrophy. An excessive loss of muscle mass is associated with a poor prognosis in several diseases and significant muscle weakness impairs the quality of life. The skeletal muscle atrophy that occurs in response to inflammatory diseases or prolonged inactivity is often associated with both oxidative and nitrosative stress. In this report, we critically review the experimental evidence that provides support for a causative link between oxidants and muscle atrophy. More specifically, this review will debate the sources of oxidant production in skeletal muscle undergoing atrophy as well as provide a detailed discussion on how reactive oxygen species and reactive nitrogen species modulate the signaling pathways that regulate both protein synthesis and protein breakdown.