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Sample records for left posterior hippocampus

  1. Alterations in right posterior hippocampus in early blind individuals

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    Chebat, Daniel-Robert; Chen, Jan-Kai; Schneider, Fabien

    2007-01-01

    This study compares hippocampal volumes of early blind and sex/age-matched sighted controls through volumetric and localization analyses. Early blind individuals showed a significantly smaller right posterior hippocampus compared with controls. No differences in total hippocampal volumes were found...... between groups and there were no within-group differences for left versus right hippocampus. Sex, age and total brain grey matter volume had no effect on hippocampal volumes. Although extensive navigational training results in structural enhancement of the hippocampus for the sighted, the reduction...... of the posterior hippocampus in early blind individuals suggests the implication of this region in visual spatial memory. Udgivelsesdato: 2007-Mar-5...

  2. Anterior/posterior competitive deactivation/activation dichotomy in the human hippocampus as revealed by a 3D navigation task.

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    Isabel Catarina Duarte

    Full Text Available Anterior/posterior long axis specialization is thought to underlie the organization of the hippocampus. However it remains unclear whether antagonistic mechanisms differentially modulate processing of spatial information within the hippocampus. We used fMRI and a virtual reality 3D paradigm to study encoding and retrieval of spatial memory during active visuospatial navigation, requiring positional encoding and retrieval of object landmarks during the path. Both encoding and retrieval elicited BOLD activation of the posterior most portion of hippocampus, while concurrent deactivations (recently shown to reflect decreases in neural responses were found in the most anterior regions. Encoding elicited stronger activity in the posterior right than the left hippocampus. The former structure also showed significantly stronger activity for allocentric vs. egocentric processing during retrieval. The anterior vs. posterior pattern mimics, from a functional point, although at much distinct temporal scales, the previous anatomical findings in London taxi drivers, whereby posterior enlargement was found at the cost of an anterior decrease, and the mirror symmetric findings observed in blind people, in whom the right anterior hippocampus was found to be larger, at the cost of a smaller posterior hippocampus, as compared with sighted people. In sum, we found a functional dichotomy whereby the anterior/posterior hippocampus shows antagonistic processing patterns for spatial encoding and retrieval of 3D spatial information. To our knowledge, this is the first study reporting such a dynamical pattern in a functional study, which suggests that differential modulation of neural responses within the human hippocampus reflects distinct roles in spatial memory processing.

  3. Impact of schizophrenia on anterior and posterior hippocampus during memory for complex scenes

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    J.D. Ragland

    2017-01-01

    Conclusions: Results suggest a gradient of hippocampal dysfunction in which posterior hippocampus – which is necessary for processing fine-grained spatial relationships – is underactive, and anterior hippocampus – which may process context more globally - is overactive.

  4. Comparison of neurodegeneration between right and left hippocampus area in rats

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    Arezo Nahavandi

    2015-02-01

    Conclusion: Our study showed different manifestations of depression after UCMS. It showed that UCMS could lead to mental depression. This study showed that the right hippocampus was more sensitive to stress than the left hippocampus. In fact, UCMS resulted in depression. The study showed that the right hippocampus was more sensitive to stress than the left hippocampus. Therefore, the main function of the right hemisphere, which is adaptation to the new environment, is disturbed more.

  5. Right Bundle-Branch Block Associated with Transient Left Posterior ...

    African Journals Online (AJOL)

    The intraventricular conduction defect of left posterior hemiblock is very uncommon. Its occurrence as a transient phenomenon during the course of acute myocardial infarction, as described in this report, is exceptionally rare. The presentation revealed a planar reorientation of QRS forces, and demonstrated the masking ...

  6. Memory of music: roles of right hippocampus and left inferior frontal gyrus.

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    Watanabe, Takamitsu; Yagishita, Sho; Kikyo, Hideyuki

    2008-01-01

    We investigated neural correlates of retrieval success for music memory using event-related functional magnetic resonance imaging. To minimize the interference from MRI scan noise, we used sparse temporal sampling technique. Newly composed music materials were employed as stimuli, which enabled us to detect regions in absence of effects of experience with the music stimuli in this study. Whole brain analyses demonstrated significant retrieval success activities in the right hippocampus, bilateral lateral temporal regions, left inferior frontal gyrus and left precuneus. Anatomically defined region-of-interests analyses showed that the activity of the right hippocampus was stronger than that of the left, while the activities of the inferior frontal gyri showed the reverse pattern. Furthermore, performance-based analyses demonstrated that the retrieval success activity of the right hippocampus was positively correlated with the corrected recognition rate, suggesting that the right hippocampus contributes to the accuracy of music retrieval outcome.

  7. Dyscalculia, dysgraphia, and left-right confusion from a left posterior peri-insular infarct.

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    Bhattacharyya, S; Cai, X; Klein, J P

    2014-01-01

    The Gerstmann syndrome of dyscalculia, dysgraphia, left-right confusion, and finger agnosia is generally attributed to lesions near the angular gyrus of the dominant hemisphere. A 68-year-old right-handed woman presented with sudden difficulty completing a Sudoku grid and was found to have dyscalculia, dysgraphia, and left-right confusion. Magnetic resonance imaging (MRI) showed a focus of abnormal reduced diffusivity in the left posterior insula and temporoparietal operculum consistent with acute infarct. Gerstmann syndrome from an insular or peri-insular lesion has not been described in the literature previously. Pathological and functional imaging studies show connections between left posterior insular region and inferior parietal lobe. We postulate that the insula and operculum lesion disrupted key functional networks resulting in a pseudoparietal presentation.

  8. Dyscalculia, Dysgraphia, and Left-Right Confusion from a Left Posterior Peri-Insular Infarct

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    S. Bhattacharyya

    2014-01-01

    Full Text Available The Gerstmann syndrome of dyscalculia, dysgraphia, left-right confusion, and finger agnosia is generally attributed to lesions near the angular gyrus of the dominant hemisphere. A 68-year-old right-handed woman presented with sudden difficulty completing a Sudoku grid and was found to have dyscalculia, dysgraphia, and left-right confusion. Magnetic resonance imaging (MRI showed a focus of abnormal reduced diffusivity in the left posterior insula and temporoparietal operculum consistent with acute infarct. Gerstmann syndrome from an insular or peri-insular lesion has not been described in the literature previously. Pathological and functional imaging studies show connections between left posterior insular region and inferior parietal lobe. We postulate that the insula and operculum lesion disrupted key functional networks resulting in a pseudoparietal presentation.

  9. The role of left posterior inferior temporal cortex in spelling.

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    Rapcsak, Steven Z; Beeson, Pélagie M

    2004-06-22

    To determine whether damage to left posterior inferior temporal cortex (PITC) is associated with agraphia and to characterize the nature of the spelling impairment. Left angular gyrus may play a critical role in spelling. However, this traditional view is challenged by reports of agraphia after left temporo-occipital lesions and by functional imaging studies demonstrating activation of left PITC during writing in normal individuals. Patients with focal damage to the left temporo-occipital cortex and normal control subjects were administered a comprehensive spelling battery that included regular words, irregular words, and nonwords as stimuli. Although patients performed worse than control subjects in all experimental conditions, the spelling deficit was particularly severe for irregular words, whereas regular word and nonword spelling were less impaired. Additional analyses indicated that orthographic regularity and word frequency had a much more pronounced effect on spelling accuracy in patients compared with control subjects. Most errors on irregular words were phonologically plausible, consistent with reliance on a sublexical phonologic spelling strategy (i.e., phoneme-grapheme conversion). Overall, the spelling impairment of the patients showed the characteristic profile of lexical agraphia. Lesion analyses indicated that the damage in the majority of patients encompassed an area within the left PITC (BA 37/20) where the authors previously obtained evidence of activation in a functional imaging study of writing in normal participants. The behavioral and neuroanatomic observations in the patients are consistent with functional imaging studies of writing in neurologically intact individuals and provide converging evidence for the role of left PITC in spelling. Together, these findings implicate left PITC as a possible neural substrate of the putative orthographic lexicon that contains stored memory representations for the written forms of familiar words.

  10. Clinico-anatomical correlations of left posterior cerebral artery occlusion

    International Nuclear Information System (INIS)

    Isono, Osamu; Shiota, Junichi; Kawamura, Mitsuru; Hirayama, Keizou; Maki, Toshiyuki.

    1988-01-01

    The relation between neurological signs and symptoms and computed tomography (CT) and magnetic resonance imaging (MRI) was examined in 11 cases of occlusion of the left posterior cerebral artery. All the patients were righthanded. Right homonimous hemianopia was noted in 8 cases, right upper quadrantanopia in 2 cases, and right lower quadrantanopia in 1 case. Of the 11 cases, alexia without agraphia was noted in 9 cases, all 9 of which showed lesions of inferior occipital cortex (lingual and fusiform gyri) and subjacent white matter. Lesions of splenium were found in only 5 of the cases of alexia without agraphia. In 2 cases with neither alexia nor agraphia, lesions were seen in the medial occipital cortex and the subjacent white matter but not in the inferior occipital lobe. Three patients had color anomia which was accompanied by memory disturbances and alexia without agraphia. In 2 of these 3, lesions were widespread in the region of the left posterior cerebral artery. Memory disturbances were observed in 6 cases, all of which also showed alexia without agraphia. The lesions extended not only of the inferior surface of the occipital lobe and along the interhemispheric fissure, but also of hippocampal and parahippocampal gyri. In 3 cases of alexia without agraphia in which no memory distrubance was found, the symptoms of alexia were slight and disappeared at an early stage. (J.P.N.)

  11. Structural development of the hippocampus and episodic memory: developmental differences along the anterior/posterior axis.

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    DeMaster, Dana; Pathman, Thanujeni; Lee, Joshua K; Ghetti, Simona

    2014-11-01

    The hippocampus is critically involved in episodic memory, yet relatively little is known about how the development of this structure contributes to the development of episodic memory during middle to late childhood. Previous research has inconsistently reported associations between hippocampal volume and episodic memory performance during this period. We argue that this inconsistency may be due to assessing the hippocampus as a whole, and propose to examine associations separately for subregions along the longitudinal axis of the hippocampus. In the present study, we examined age-related differences in volumes of the hippocampal head, body, and tail, and collected episodic memory measures in children ages 8-11 years and young adults (N = 62). We found that adults had a smaller right hippocampal head, larger hippocampal body bilaterally, and smaller right hippocampal tail compared with children. In adults, but not in children, better episodic memory performance was associated with smaller right hippocampal head and larger hippocampal body. In children, but not in adults, better episodic memory was associated with larger left hippocampal tail. Overall, the results suggest that protracted development of hippocampal subregions contribute to age-related differences in episodic memory. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  12. Motion verb sentences activate left posterior middle temporal cortex despite static context

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    Wallentin, M; Ellegaard Lund, Torben; Østergaard, Svend

    2005-01-01

    The left posterior middle temporal region, anterior to V5/MT, has been shown to be responsive both to images with implied motion, to simulated motion, and to motion verbs. In this study, we investigated whether sentence context alters the response of the left posterior middle temporal region....... 'Fictive motion' sentences are sentences in which an inanimate subject noun, semantically incapable of self movement, is coupled with a motion verb, yielding an apparent semantic contradiction (e.g. 'The path comes into the garden.'). However, this context yields no less activation in the left posterior...... middle temporal region than sentences in which the motion can be applied to the subject noun. We speculate that the left posterior middle temporal region activity in fictive motion sentences reflects the fact that the hearer applies motion to the depicted scenario by scanning it egocentrically...

  13. Unilateral hyperplasia of the left posterior arch and associated vertebral schisis at C6 level

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    Esposito, Giuseppe; Bonis, Pasquale de; Tamburrini, Gianpiero; Massimi, Luca; Rocco, Concezio di [Catholic University, School of Medicine, Department of Pediatric Neurosurgery, Rome (Italy); Byvaltsev, Vadim [Irkutsk Railway Clinical Hospital, Department of Neurosurgery, Irkutsk (Russian Federation); Leone, Antonio [Catholic University, School of Medicine, Department of Bioimaging and Radiological Sciences, Rome (Italy)

    2009-12-15

    We report on a 5-year-old girl with unilateral hyperplasia of the left posterior arch of C6 associated with spina bifida occulta at the same level. Anteroposterior and lateral radiographs of the cervical spine showed hypertrophy of the left lamina as well as overgrowth and elongation of the left spinous process of the sixth cervical vertebra. Computed tomography (CT) examination better depicted this congenital variant and clearly showed the associated schisis of the posterior arch at the same level. Magnetic resonance (MR) imaging examination ruled out other spinal anomalies. The neck pain, the young age of the patient and the local aesthetic abnormality contributed to the surgical indication. To the best of our knowledge, this is the first case in the English literature of unilateral hyperplasia of a posterior cervical arch. Only one previous study has reported a similar congenital anomaly, but it was limited to the left side of the spinous process. (orig.)

  14. Unilateral hyperplasia of the left posterior arch and associated vertebral schisis at C6 level

    International Nuclear Information System (INIS)

    Esposito, Giuseppe; Bonis, Pasquale de; Tamburrini, Gianpiero; Massimi, Luca; Rocco, Concezio di; Byvaltsev, Vadim; Leone, Antonio

    2009-01-01

    We report on a 5-year-old girl with unilateral hyperplasia of the left posterior arch of C6 associated with spina bifida occulta at the same level. Anteroposterior and lateral radiographs of the cervical spine showed hypertrophy of the left lamina as well as overgrowth and elongation of the left spinous process of the sixth cervical vertebra. Computed tomography (CT) examination better depicted this congenital variant and clearly showed the associated schisis of the posterior arch at the same level. Magnetic resonance (MR) imaging examination ruled out other spinal anomalies. The neck pain, the young age of the patient and the local aesthetic abnormality contributed to the surgical indication. To the best of our knowledge, this is the first case in the English literature of unilateral hyperplasia of a posterior cervical arch. Only one previous study has reported a similar congenital anomaly, but it was limited to the left side of the spinous process. (orig.)

  15. Left posterior BA37 is involved in object recognition: a TMS study

    DEFF Research Database (Denmark)

    Stewart, Lauren; Meyer, Bernd-Ulrich; Frith, Uta

    2001-01-01

    Functional imaging studies have proposed a role for left BA37 in phonological retrieval, semantic processing, face processing and object recognition. The present study targeted the posterior aspect of BA37 to see whether a deficit, specific to one of the above types of processing could be induced...

  16. BOLD Response to Motion Verbs in Left Posterior Middle Temporal Gyrus during Story Comprehension

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    Wallentin, Mikkel; Nielsen, Andreas Hojlund; Vuust, Peter; Dohn, Anders; Roepstorff, Andreas; Lund, Torben Ellegaard

    2011-01-01

    A primary focus within neuroimaging research on language comprehension is on the distribution of semantic knowledge in the brain. Studies have shown that the left posterior middle temporal gyrus (LPMT), a region just anterior to area MT/V5, is important for the processing of complex action knowledge. It has also been found that motion verbs cause…

  17. BOLD response to motion verbs in left posterior middle temporal gyrus during story comprehension

    DEFF Research Database (Denmark)

    Wallentin, Mikkel; Nielsen, Andreas Højlund; Vuust, Peter

    2011-01-01

    A primary focus within neuroimaging research on language comprehension is on the distribution of semantic knowledge in the brain. Studies have shown that the left posterior middle temporal gyrus (LPMT), a region just anterior to area MT/V5, is important for the processing of complex action...

  18. Functional characteristics of developmental dyslexia in left-hemispheric posterior brain regions predate reading onset.

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    Raschle, Nora Maria; Zuk, Jennifer; Gaab, Nadine

    2012-02-07

    Individuals with developmental dyslexia (DD) show a disruption in posterior left-hemispheric neural networks during phonological processing. Additionally, compensatory mechanisms in children and adults with DD have been located within frontal brain areas. However, it remains unclear when and how differences in posterior left-hemispheric networks manifest and whether compensatory mechanisms have already started to develop in the prereading brain. Here we investigate functional networks during phonological processing in 36 prereading children with a familial risk for DD (n = 18, average age = 66.50 mo) compared with age and IQ-matched controls (n = 18; average age = 65.61 mo). Functional neuroimaging results reveal reduced activation in prereading children with a family-history of DD (FHD(+)), compared with those without (FHD(-)), in bilateral occipitotemporal and left temporoparietal brain regions. This finding corresponds to previously identified hypoactivations in left hemispheric posterior brain regions for school-aged children and adults with a diagnosis of DD. Furthermore, left occipitotemporal and temporoparietal brain activity correlates positively with prereading skills in both groups. Our results suggest that differences in neural correlates of phonological processing in individuals with DD are not a result of reading failure, but are present before literacy acquisition starts. Additionally, no hyperactivation in frontal brain regions was observed, suggesting that compensatory mechanisms for reading failure are not yet present. Future longitudinal studies are needed to determine whether the identified differences may serve as neural premarkers for the early identification of children at risk for DD.

  19. Posterior non-ischemic left ventricular aneurysm. Report of 2 surgical cases.

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    Lioulias, A G; Kokotsakis, J N; Skouteli, E A T; Boulafendis, D G

    2002-12-01

    Posterior non-ischemic left ventricular aneurysms are unusual aneurysms of different etiology that develop adjacent to the mitral valve annulus causing mitral regurgitation and progressive heart failure. Surgical correction is mandatory and involves repair of the aneurysm along with repair or replacement of the mitral valve. Two cases of posterior non-ischemic left ventricular aneurysms are reported. Both patients were females (19 and 9 years old) and they presented with symptoms of progressive heart failure. Definite diagnosis was made with transesophageal echocardiography (TEE) and confirmed with left ventriculography. Both patients were successfully treated by surgery. The first patient underwent repair of the aneurysm from inside the left ventricle and mitral valve replacement. The second patient had resection of the aneurysm through an extracardiac route. Both patients are in NYHA class 1, 5 and 4 years respectively after their operation with no evidence of mitral valve dysfunction. Posterior non-ischemic left ventricular aneurysms can securely be diagnosed by TEE and angiocardiography. Surgical treatment is mandatory in order to forestall potential life threatening cardiovascular events and should be tailored to the operative findings.

  20. Specific patterns of whole-brain structural covariance of the anterior and posterior hippocampus in young APOE ε4 carriers.

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    Stening, Eva; Persson, Jonas; Eriksson, Elias; Wahlund, Lars-Olof; Zetterberg, Henrik; Söderlund, Hedvig

    2017-05-30

    Apolipoprotein E (APOE) ε4 has been associated with smaller hippocampal volumes in healthy aging, while findings in young adults are inconclusive. Previous studies have mostly used univariate methods, and without considering potential anterior/posterior differences. Here, we used a multivariate method, partial least squares, and assessed whole-brain structural covariance of the anterior (aHC) and posterior (pHC) hippocampus in young adults (n=97) as a function of APOE ε4 status and sex. Two significant patterns emerged: (1) specific structural covariance of the aHC with frontal regions, temporal and occipital areas in APOE ε4 women, whereas the volume of both the aHC and pHC in all other groups co-varied with frontal, parietal and cerebellar areas; and (2) opposite structural covariance of the pHC in ε4 carriers compared to the aHC in non-carriers, with the pHC of ε4 carriers covarying with parietal and frontal areas, and the aHC of ε4 non-carriers covarying with motor areas and the middle frontal gyrus. APOE ε4 has in young adults been associated with better episodic and spatial memory, functions involving the aHC and pHC, respectively. We found no associations between structural covariance and performance, suggesting that other factors underlie the performance differences seen between carriers and non-carriers. Our findings indicate that APOE ε4 carriers and non-carriers differ in hippocampal organization and that there are differences as a function of sex and hippocampal segment. They stress the need to consider the hippocampus as a heterogeneous structure, and highlight the benefits of multivariate methods in assessing group differences in the brain. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Epicardial mapping of ventricular fibrillation over the posterior descending artery and left posterior papillary muscle of the swine heart.

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    Nielsen, Thomas D; Huang, Jian; Rogers, Jack M; Killingsworth, Cheryl R; Ideker, Raymond E

    2009-01-01

    Recent studies suggest that during ventricular fibrillation (VF) epicardial vessels may be a site of conduction block and the posterior papillary muscle (PPM) in the left ventricle (LV) may be the location of a "mother rotor." The goal of this study was to obtain evidence to support or refute these possibilities. Epicardial activation over the posterior LV and right ventricle (RV) was mapped during the first 20 s of electrically induced VF in six open-chest pigs with a 504 electrode plaque covering a 20 cm(2) area centered over the posterior descending artery (PDA). The locations of epicardial breakthrough as well as reentry clustered in time and space during VF. Spatially, reentry occurred significantly more frequently over the LV than the RV in all 48 episodes, and breakthrough clustered near the PPM (p < 0.001). Significant temporal clustering occurred in 79% of breakthrough episodes and 100% of reentry episodes. These temporal clusters occurred at different times so that there was significantly less breakthrough when reentry was present (p < 0.0001). Conduction block occurred significantly more frequently near the PDA than elsewhere. The PDA is a site of epicardial block which may contribute to VF maintenance. Epicardial breakthrough clusters near the PPM. Reentry also clusters in space but at a separate site. The fact that breakthrough and reentry cluster at different locations and at different times supports the possibility of a drifting filament at the PPM so that at times reentry is present on the surface but at other times the reentrant wavefront breaks through to the epicardium.

  2. De novo formation of left-right asymmetry by posterior tilt of nodal cilia.

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    Shigenori Nonaka

    2005-08-01

    Full Text Available In the developing mouse embryo, leftward fluid flow on the ventral side of the node determines left-right (L-R asymmetry. However, the mechanism by which the rotational movement of node cilia can generate a unidirectional flow remains hypothetical. Here we have addressed this question by motion and morphological analyses of the node cilia and by fluid dynamic model experiments. We found that the cilia stand, not perpendicular to the node surface, but tilted posteriorly. We further confirmed that such posterior tilt can produce leftward flow in model experiments. These results strongly suggest that L-R asymmetry is not the descendant of pre-existing L-R asymmetry within each cell but is generated de novo by combining three sources of spatial information: antero-posterior and dorso-ventral axes, and the chirality of ciliary movement.

  3. Left posterior BA37 is involved in object recognition: a TMS study

    DEFF Research Database (Denmark)

    Stewart, Lauren; Meyer, Bernd-Ulrich; Frith, Uta

    2001-01-01

    Functional imaging studies have proposed a role for left BA37 in phonological retrieval, semantic processing, face processing and object recognition. The present study targeted the posterior aspect of BA37 to see whether a deficit, specific to one of the above types of processing could be induced...... to name pictures when TMS was given over lBA37 compared to vertex or rBA37. rTMS over lBA37 had no significant effect on word reading, nonword reading or colour naming. The picture naming deficit is suggested to result from a disruption to object recognition processes. This study corroborates the finding...... from a recent imaging study, that the most posterior part of left hemispheric BA37 has a necessary role in object recognition....

  4. Improving ideomotor limb apraxia by electrical stimulation of the left posterior parietal cortex.

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    Bolognini, Nadia; Convento, Silvia; Banco, Elisabetta; Mattioli, Flavia; Tesio, Luigi; Vallar, Giuseppe

    2015-02-01

    Limb apraxia, a deficit of planning voluntary gestures, is most frequently caused by damage to the left hemisphere, where, according to an influential neurofunctional model, gestures are planned, before being executed through the motor cortex of the hemisphere contralateral to the acting hand. We used anodal transcranial direct current stimulation delivered to the left posterior parietal cortex (PPC), the right motor cortex (M1), and a sham stimulation condition, to modulate the ability of six left-brain-damaged patients with ideomotor apraxia, and six healthy control subjects, to imitate hand gestures, and to perform skilled hand movements using the left hand. Transcranial direct current stimulation delivered to the left PPC reduced the time required to perform skilled movements, and planning, but not execution, times in imitating gestures, in both patients and controls. In patients, the amount of decrease of planning times brought about by left PPC transcranial direct current stimulation was influenced by the size of the parietal lobe damage, with a larger parietal damage being associated with a smaller improvement. Of interest from a clinical perspective, left PPC stimulation also ameliorated accuracy in imitating hand gestures in patients. Instead, transcranial direct current stimulation to the right M1 diminished execution, but not planning, times in both patients and healthy controls. In conclusion, by using a transcranial stimulation approach, we temporarily improved ideomotor apraxia in the left hand of left-brain-damaged patients, showing a role of the left PPC in planning gestures. This evidence opens up novel perspectives for the use of transcranial direct current stimulation in the rehabilitation of limb apraxia. © The Author (2014). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Both left and right posterior parietal activations contribute to compensatory processes in normal aging

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    Huang, Chih-Mao; Polk, Thad A.; Goh, Joshua O.; Park, Denise C.

    2012-01-01

    Older adults often exhibit greater brain activation in prefrontal cortex compared to younger adults, and there is some evidence that this increased activation compensates for age-related neural degradation that would otherwise adversely affect cognitive performance. Less is known about aging and compensatory recruitment in the parietal cortex. In this event-related functional magnetic resonance imaging study, we presented healthy young and old participants with two Stroop-like tasks (number magnitude and physical size). In young, the number magnitude task activated right parietal cortex and the physical size task activated left parietal cortex. In older adults, we observed contralateral parietal recruitment that depended on the task: in the number magnitude task older participants recruited left posterior parietal cortex (in addition to the right parietal activity observed in young) while in the physical size task they recruited right (in addition to left) posterior parietal cortex. In both cases, the additional parietal activity was associated with better performance suggesting that it played a compensatory role. Older adults also recruited left prefrontal cortex during both tasks and this common activation was also associated with better performance. The results provide evidence for task-specific compensatory recruitment in parietal cortex as well as task-independent compensatory recruitment in prefrontal cortex in normal aging. PMID:22063904

  6. Aphasia with left occipitotemporal hypometabolism: a novel presentation of posterior cortical atrophy?

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    Wicklund, Meredith R; Duffy, Joseph R; Strand, Edythe A; Whitwell, Jennifer L; Machulda, Mary M; Josephs, Keith A

    2013-09-01

    Alzheimer's disease is a common neurodegenerative disease often characterized by initial episodic memory loss. Atypical focal cortical presentations have been described, including the logopenic variant of primary progressive aphasia (lvPPA) which presents with language impairment, and posterior cortical atrophy (PCA) which presents with prominent visuospatial deficits. Both lvPPA and PCA are characterized by specific patterns of hypometabolism: left temporoparietal in lvPPA and bilateral parietoccipital in PCA. However, not every patient fits neatly into these categories. We retrospectively identified two patients with progressive aphasia and visuospatial deficits from a speech and language based disorders study. The patients were further characterized by MRI, fluorodeoxyglucose F18 and Pittsburgh Compound B (PiB) positron emission tomography. Two women, aged 62 and 69, presented with a history of a few years of progressive aphasia characterized by fluent output with normal grammar and syntax, anomia without loss of word meaning, and relatively spared repetition. They demonstrated striking deficits in visuospatial function for which they were lacking insight. Prominent hypometabolism was noted in the left occipitotemporal region and diffuse retention of PiB was noted. Posterior cortical atrophy may present focally with left occipitotemporal metabolism characterized clinically with a progressive fluent aphasia and prominent ventral visuospatial deficits with loss of insight. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Dissociative Disturbance in Hangul-Hanja Reading after a Left Posterior Occipital Lesion

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    Key-Chung Park

    2008-01-01

    Full Text Available Since the Korean language has two distinct writing systems, phonogram (Hangul and ideogram (Hanja: Chinese characters, alexia can present with dissociative disturbances in reading between the two systems. A 74-year-old right-handed man presented with a prominent reading impairment in Hangul with agraphia of both Hangul and Hanja after a left posterior occipital- parietal lesion. He could not recognize single syllable words and nonwords in Hangul, and visual errors were predominant in both Hanja reading and the Korean Boston Naming Test. In addition, he had difficulties in visuoperceptual tests including Judgment of Line Orientation, Hierarchical Navon figures, and complex picture scanning. These findings are consistent with the hypothesis that Hangul reading impairment results from a general visual perceptual deficit. However, this assumption cannot explain why performance on visually complex Hanja was better than performance on visually simple Hanja in our patient. In addition, the patient did not demonstrate higher accuracy on Hanja characters with fewer strokes than on words with more strokes. Thus, we speculate that the left posterior occipital area may be specialized for Hangul letter identification in this patient. This case demonstrates that Hangul-Hanja reading dissociation impairment can occur after occipital-parietal lesions.

  8. Loss of resting-state posterior cingulate flexibility is associated with memory disturbance in left temporal lobe epilepsy.

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    Douw, Linda; Leveroni, Catherine L; Tanaka, Naoaki; Emerton, Britt C; Cole, Andrew J; Cole, Andrew C; Reinsberger, Claus; Stufflebeam, Steven M

    2015-01-01

    The association between cognition and resting-state fMRI (rs-fMRI) has been the focus of many recent studies, most of which use stationary connectivity. The dynamics or flexibility of connectivity, however, may be seminal for understanding cognitive functioning. In temporal lobe epilepsy (TLE), stationary connectomic correlates of impaired memory have been reported mainly for the hippocampus and posterior cingulate cortex (PCC). We therefore investigate resting-state and task-based hippocampal and PCC flexibility in addition to stationary connectivity in left TLE (LTLE) patients. Sixteen LTLE patients were analyzed with respect to rs-fMRI and task-based fMRI (t-fMRI), and underwent clinical neuropsychological testing. Flexibility of connectivity was calculated using a sliding-window approach by determining the standard deviation of Fisher-transformed Pearson correlation coefficients over all windows. Stationary connectivity was also calculated. Disturbed memory was operationalized as having at least one memory subtest score equal to or below the 5th percentile compared to normative data. Lower PCC flexibility, particularly in the contralateral (i.e. right) hemisphere, was found in memory-disturbed LTLE patients, who had up to 22% less flexible connectivity. No significant group differences were found with respect to hippocampal flexibility, stationary connectivity during both rs-fMRI and t-fMRI, or flexibility during t-fMRI. Contralateral resting-state PCC flexibility was able to classify all but one patient with respect to their memory status (94% accuracy). Flexibility of the PCC during rest relates to memory functioning in LTLE patients. Loss of flexible connectivity to the rest of the brain originating from the PCC, particularly contralateral to the seizure focus, is able to discern memory disturbed patients from their preserved counterparts. This study indicates that the dynamics of resting-state connectivity are associated with cognitive status of LTLE

  9. Loss of resting-state posterior cingulate flexibility is associated with memory disturbance in left temporal lobe epilepsy.

    Directory of Open Access Journals (Sweden)

    Linda Douw

    Full Text Available The association between cognition and resting-state fMRI (rs-fMRI has been the focus of many recent studies, most of which use stationary connectivity. The dynamics or flexibility of connectivity, however, may be seminal for understanding cognitive functioning. In temporal lobe epilepsy (TLE, stationary connectomic correlates of impaired memory have been reported mainly for the hippocampus and posterior cingulate cortex (PCC. We therefore investigate resting-state and task-based hippocampal and PCC flexibility in addition to stationary connectivity in left TLE (LTLE patients. Sixteen LTLE patients were analyzed with respect to rs-fMRI and task-based fMRI (t-fMRI, and underwent clinical neuropsychological testing. Flexibility of connectivity was calculated using a sliding-window approach by determining the standard deviation of Fisher-transformed Pearson correlation coefficients over all windows. Stationary connectivity was also calculated. Disturbed memory was operationalized as having at least one memory subtest score equal to or below the 5th percentile compared to normative data. Lower PCC flexibility, particularly in the contralateral (i.e. right hemisphere, was found in memory-disturbed LTLE patients, who had up to 22% less flexible connectivity. No significant group differences were found with respect to hippocampal flexibility, stationary connectivity during both rs-fMRI and t-fMRI, or flexibility during t-fMRI. Contralateral resting-state PCC flexibility was able to classify all but one patient with respect to their memory status (94% accuracy. Flexibility of the PCC during rest relates to memory functioning in LTLE patients. Loss of flexible connectivity to the rest of the brain originating from the PCC, particularly contralateral to the seizure focus, is able to discern memory disturbed patients from their preserved counterparts. This study indicates that the dynamics of resting-state connectivity are associated with cognitive status

  10. Impaired spontaneous belief inference following acquired damage to the left posterior temporoparietal junction.

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    Biervoye, Aurélie; Dricot, Laurence; Ivanoiu, Adrian; Samson, Dana

    2016-10-01

    Efficient social interactions require taking into account other people's mental states such as their beliefs, intentions or emotions. Recent studies have shown that in some social situations at least, we do spontaneously take into account others' mental states. The extent to which we have dedicated brain areas for such spontaneous perspective taking is however still unclear. Here, we report two brain-damaged patients whose common lesions were almost exclusively in the left posterior temporoparietal junction (TPJp) and who both showed the same striking and distinctive theory of mind (ToM) deficit. More specifically, they had an inability to take into account someone else's belief unless they were explicitly instructed to tell what that other person thinks or what that person will do. These patients offer a unique insight into the causal link between a specific subregion of the TPJ and a specific cognitive facet of ToM. © The Author (2016). Published by Oxford University Press.

  11. Metastatic myocardial abscess on the posterior wall of the left ventricle: a case report

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    Iqbal Javaid

    2008-08-01

    Full Text Available Abstract Introduction Myocardial abscess is a rare and potentially fatal condition. Metastatic myocardial abscess in the setting of infective endocarditis has been infrequently reported in the medical literature. To the best of the authors' knowledge no case of myocardial abscess affecting the free wall of the left ventricle secondary to infective endocarditis of a right-sided heart valve has been reported previously. Case presentation We report a case of tricuspid valve endocarditis caused by Staphylococcus aureus and resulting in a myocardial abscess on the posterior wall of the left ventricle, far from the active valvular infection. We also briefly discuss the role of different investigation modalities including cardiac magnetic resonance imaging in diagnosing myocardial abscess. Conclusion Myocardial abscess is a life-threatening illness. A high index of clinical suspicion is required to make a prompt diagnosis. Final diagnosis may need multi-modality imaging. An early diagnosis, aggressive medical therapy, multidisciplinary care and timely surgical intervention may save life in this otherwise fatal condition.

  12. Transcranial Magnetic Stimulation over Left Inferior Frontal and Posterior Temporal Cortex Disrupts Gesture-Speech Integration.

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    Zhao, Wanying; Riggs, Kevin; Schindler, Igor; Holle, Henning

    2018-02-21

    Language and action naturally occur together in the form of cospeech gestures, and there is now convincing evidence that listeners display a strong tendency to integrate semantic information from both domains during comprehension. A contentious question, however, has been which brain areas are causally involved in this integration process. In previous neuroimaging studies, left inferior frontal gyrus (IFG) and posterior middle temporal gyrus (pMTG) have emerged as candidate areas; however, it is currently not clear whether these areas are causally or merely epiphenomenally involved in gesture-speech integration. In the present series of experiments, we directly tested for a potential critical role of IFG and pMTG by observing the effect of disrupting activity in these areas using transcranial magnetic stimulation in a mixed gender sample of healthy human volunteers. The outcome measure was performance on a Stroop-like gesture task (Kelly et al., 2010a), which provides a behavioral index of gesture-speech integration. Our results provide clear evidence that disrupting activity in IFG and pMTG selectively impairs gesture-speech integration, suggesting that both areas are causally involved in the process. These findings are consistent with the idea that these areas play a joint role in gesture-speech integration, with IFG regulating strategic semantic access via top-down signals acting upon temporal storage areas. SIGNIFICANCE STATEMENT Previous neuroimaging studies suggest an involvement of inferior frontal gyrus and posterior middle temporal gyrus in gesture-speech integration, but findings have been mixed and due to methodological constraints did not allow inferences of causality. By adopting a virtual lesion approach involving transcranial magnetic stimulation, the present study provides clear evidence that both areas are causally involved in combining semantic information arising from gesture and speech. These findings support the view that, rather than being

  13. Comparison of Metabolite Concentrations in the Left Dorsolateral Prefrontal Cortex, the Left Frontal White Matter, and the Left Hippocampus in Patients in Stable Schizophrenia Treated with Antipsychotics with or without Antidepressants. ¹H-NMR Spectroscopy Study.

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    Strzelecki, Dominik; Grzelak, Piotr; Podgórski, Michał; Kałużyńska, Olga; Stefańczyk, Ludomir; Kotlicka-Antczak, Magdalena; Gmitrowicz, Agnieszka

    2015-10-15

    Managing affective, negative, and cognitive symptoms remains the most difficult therapeutic problem in stable phase of schizophrenia. Efforts include administration of antidepressants. Drugs effects on brain metabolic parameters can be evaluated by means of proton nuclear magnetic resonance (¹H-NMR) spectroscopy. We compared spectroscopic parameters in the left prefrontal cortex (DLPFC), the left frontal white matter (WM) and the left hippocampus and assessed the relationship between treatment and the spectroscopic parameters in both groups. We recruited 25 patients diagnosed with schizophrenia (DSM-IV-TR), with dominant negative symptoms and in stable clinical condition, who were treated with antipsychotic and antidepressive medication for minimum of three months. A group of 25 patients with schizophrenia, who were taking antipsychotic drugs but not antidepressants, was matched. We compared metabolic parameters (N-acetylaspartate (NAA), myo-inositol (mI), glutamatergic parameters (Glx), choline (Cho), and creatine (Cr)) between the two groups. All patients were also assessed with the Positive and Negative Syndrome Scale (PANSS) and the Calgary Depression Scale for Schizophrenia (CDSS). In patients receiving antidepressants we observed significantly higher NAA/Cr and NAA/Cho ratios within the DLPFC, as well as significantly higher mI/Cr within the frontal WM. Moreover, we noted significantly lower values of parameters associated with the glutamatergic transmission--Glx/Cr and Glx/Cho in the hippocampus. Doses of antipsychotic drugs in the group treated with antidepressants were also significantly lower in the patients showing similar severity of psychopathology.

  14. Comparison of Metabolite Concentrations in the Left Dorsolateral Prefrontal Cortex, the Left Frontal White Matter, and the Left Hippocampus in Patients in Stable Schizophrenia Treated with Antipsychotics with or without Antidepressants. 1H-NMR Spectroscopy Study

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    Strzelecki, Dominik; Grzelak, Piotr; Podgórski, Michał; Kałużyńska, Olga; Stefańczyk, Ludomir; Kotlicka-Antczak, Magdalena; Gmitrowicz, Agnieszka

    2015-01-01

    Managing affective, negative, and cognitive symptoms remains the most difficult therapeutic problem in stable phase of schizophrenia. Efforts include administration of antidepressants. Drugs effects on brain metabolic parameters can be evaluated by means of proton nuclear magnetic resonance (1H-NMR) spectroscopy. We compared spectroscopic parameters in the left prefrontal cortex (DLPFC), the left frontal white matter (WM) and the left hippocampus and assessed the relationship between treatment and the spectroscopic parameters in both groups. We recruited 25 patients diagnosed with schizophrenia (DSM-IV-TR), with dominant negative symptoms and in stable clinical condition, who were treated with antipsychotic and antidepressive medication for minimum of three months. A group of 25 patients with schizophrenia, who were taking antipsychotic drugs but not antidepressants, was matched. We compared metabolic parameters (N-acetylaspartate (NAA), myo-inositol (mI), glutamatergic parameters (Glx), choline (Cho), and creatine (Cr)) between the two groups. All patients were also assessed with the Positive and Negative Syndrome Scale (PANSS) and the Calgary Depression Scale for Schizophrenia (CDSS). In patients receiving antidepressants we observed significantly higher NAA/Cr and NAA/Cho ratios within the DLPFC, as well as significantly higher mI/Cr within the frontal WM. Moreover, we noted significantly lower values of parameters associated with the glutamatergic transmission—Glx/Cr and Glx/Cho in the hippocampus. Doses of antipsychotic drugs in the group treated with antidepressants were also significantly lower in the patients showing similar severity of psychopathology. PMID:26501256

  15. BOLD response to motion verbs in left posterior middle temporal gyrus during story comprehension.

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    Wallentin, Mikkel; Nielsen, Andreas Højlund; Vuust, Peter; Dohn, Anders; Roepstorff, Andreas; Lund, Torben Ellegaard

    2011-12-01

    A primary focus within neuroimaging research on language comprehension is on the distribution of semantic knowledge in the brain. Studies have shown that the left posterior middle temporal gyrus (LPMT), a region just anterior to area MT/V5, is important for the processing of complex action knowledge. It has also been found that motion verbs cause activation in LPMT. In this experiment we investigated whether this effect could be replicated in a setting resembling real life language comprehension, i.e. without any overt behavioral task during passive listening to a story. During fMRI participants listened to a recording of the story "The Ugly Duckling". We incorporated a nuisance elimination regression approach for factoring out known nuisance variables both in terms of physiological noise, sound intensity, linguistic variables and emotional content. Compared to the remaining text, clauses containing motion verbs were accompanied by a robust activation of LPMT with no other significant effects, consistent with the hypothesis that this brain region is important for processing motion knowledge, even during naturalistic language comprehension conditions. 2011 Elsevier Inc. All rights reserved.

  16. Planar cell polarity enables posterior localization of nodal cilia and left-right axis determination during mouse and Xenopus embryogenesis.

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    Dragana Antic

    2010-02-01

    Full Text Available Left-right asymmetry in vertebrates is initiated in an early embryonic structure called the ventral node in human and mouse, and the gastrocoel roof plate (GRP in the frog. Within these structures, each epithelial cell bears a single motile cilium, and the concerted beating of these cilia produces a leftward fluid flow that is required to initiate left-right asymmetric gene expression. The leftward fluid flow is thought to result from the posterior tilt of the cilia, which protrude from near the posterior portion of each cell's apical surface. The cells, therefore, display a morphological planar polarization. Planar cell polarity (PCP is manifested as the coordinated, polarized orientation of cells within epithelial sheets, or as directional cell migration and intercalation during convergent extension. A set of evolutionarily conserved proteins regulates PCP. Here, we provide evidence that vertebrate PCP proteins regulate planar polarity in the mouse ventral node and in the Xenopus gastrocoel roof plate. Asymmetric anterior localization of VANGL1 and PRICKLE2 (PK2 in mouse ventral node cells indicates that these cells are planar polarized by a conserved molecular mechanism. A weakly penetrant Vangl1 mutant phenotype suggests that compromised Vangl1 function may be associated with left-right laterality defects. Stronger functional evidence comes from the Xenopus GRP, where we show that perturbation of VANGL2 protein function disrupts the posterior localization of motile cilia that is required for leftward fluid flow, and causes aberrant expression of the left side-specific gene Nodal. The observation of anterior-posterior PCP in the mouse and in Xenopus embryonic organizers reflects a strong evolutionary conservation of this mechanism that is important for body plan determination.

  17. Correlations between measures of executive attention and cortical thickness of left posterior middle frontal gyrus - a dichotic listening study

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    Lundervold Arvid

    2009-10-01

    Full Text Available Abstract Background The frontal lobe has been associated to a wide range of cognitive control functions and is also vulnerable to degeneration in old age. A recent study by Thomsen and colleagues showed a difference between a young and old sample in grey matter density and activation in the left middle frontal cortex (MFC and performance on a dichotic listening task. The present study investigated this brain behaviour association within a sample of healthy older individuals, and predicted a positive correlation between performance in a condition requiring executive attention and measures of grey matter structure of the posterior left MFC. Methods A dichotic listening forced attention paradigm was used to measure attention control functions. Subjects were instructed to report only the left or the right ear syllable of a dichotically presented consonant-vowel syllable pair. A conflict situation appears when subjects are instructed to report the left ear stimulus, caused by the conflict with the bottom-up, stimulus-driven right ear advantage. Overcoming this processing conflict was used as a measure of executive attention. Thickness and volumes of frontal lobe regions were derived from automated segmentation of 3D magnetic resonance image acquisitions. Results The results revealed a statistically significant positive correlation between the thickness measure of the left posterior MFC and performance on the dichotic listening measures of executive attention. Follow-up analyses showed that this correlation was only statistically significant in the subgroup that showed the typical bottom-up, stimulus-driven right ear advantage. Conclusion The results suggest that the left MFC is a part of an executive attention network, and that the dichotic listening forced attention paradigm may be a feasible tool for assessing subtle attentional dysfunctions in older adults.

  18. Decreased Left Posterior Insular Activity During Auditory Language in Autism American Journal of Neuroradiology – January 2010

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    Anderson, Jeffrey S.; Lange, Nicholas; Froehlich, Alyson; DuBray, Molly B.; Druzgal, T. Jason; Froimowitz, Michael P.; Alexander, Andrew L.; Bigler, Erin D.; Lainhart, Janet E.

    2009-01-01

    Background and Purpose Individuals with autism spectrum disorders often exhibit atypical language patterns including delay of speech onset, literal speech interpretation, and poor recognition of social and emotional cues in speech. We acquired fMRI images during an auditory language task to evaluate for systematic differences in language network activation between control and high-functioning autistic populations. Materials and Methods 41 right-handed male subjects (26 high-functioning autistic, 15 control) were studied using an auditory phrase recognition task, and areas of differential activation between groups were identified. Hand preference, verbal IQ, age, and language function testing were included as covariables in the analysis. Results Control and autistic subjects showed similar language activation networks, with two notable differences. Control subjects showed significantly increased activation in the left posterior insula compared to autistic subjects (p<0.05, FDR), and autistic subjects showed increased bilaterality of receptive language compared to control subjects. Higher receptive language score on standardized testing was associated with greater activation of the posterior aspect of left Wernicke’s area. Higher verbal IQ was associated with greater activation of bilateral Broca’s area and involvement of prefrontal cortex and lateral premotor cortex. Conclusion Control subjects showed greater activation of the posterior insula during receptive language, which may correlate with impaired emotive processing of language in autism. Autism subjects showed greater bilateral activation of receptive language areas that was out of proportion to differences in hand preference in autism and control populations. PMID:19749222

  19. Reinnervation of bilateral posterior cricoarytenoid muscles using the left phrenic nerve in patients with bilateral vocal fold paralysis.

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    Meng Li

    Full Text Available OBJECTIVE: To evaluate the feasibility, effectiveness, and safety of reinnervation of the bilateral posterior cricoarytenoid (PCA muscles using the left phrenic nerve in patients with bilateral vocal fold paralysis. METHODS: Forty-four patients with bilateral vocal fold paralysis who underwent reinnervation of the bilateral PCA muscles using the left phrenic nerve were enrolled in this study. Videostroboscopy, perceptual evaluation, acoustic analysis, maximum phonation time, pulmonary function testing, and laryngeal electromyography were performed preoperatively and postoperatively. Patients were followed-up for at least 1 year after surgery. RESULTS: Videostroboscopy showed that within 1 year after reinnervation, abductive movement could be observed in the left vocal folds of 87% of patients and the right vocal folds of 72% of patients. Abductive excursion on the left side was significantly larger than that on the right side (P 0.05. No patients developed immediate dyspnea after surgery, and the pulmonary function parameters recovered to normal reference value levels within 1 year. Postoperative laryngeal electromyography confirmed successful reinnervation of the bilateral PCA muscles. Eighty-seven percent of patients in this series were decannulated and did not show obvious dyspnea after physical activity. Those who were decannulated after subsequent arytenoidectomy were not included in calculating the success rate of decannulation. CONCLUSIONS: Reinnervation of the bilateral PCA muscles using the left phrenic nerve can restore inspiratory vocal fold abduction to a physiologically satisfactory extent while preserving phonatory function at the preoperative level without evident morbidity.

  20. The regional neuronal activity in left posterior middle temporal gyrus is correlated with the severity of chronic aphasia.

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    Li, Jianlin; Du, Dunren; Gao, Wei; Sun, Xichun; Xie, Haizhu; Zhang, Gang; Li, Jian; Li, Honglun; Li, Kefeng

    2017-01-01

    Aphasia is one of the most disabling cognitive deficits affecting >2 million people in the USA. The neuroimaging characteristics of chronic aphasic patients (>6 months post onset) remain largely unknown. The objective of this study was to investigate the regional signal changes of spontaneous neuronal activity of brain and the inter-regional connectivity in chronic aphasia. Resting-state blood oxygenation level-dependent functional magnetic resonance imaging (fMRI) was used to obtain fMRI data from 17 chronic aphasic patients and 20 healthy control subjects in a Siemens Verio 3.0T MR Scanner. The amplitude of low-frequency fluctuation (ALFF) was determined, which directly reflects the regional neuronal activity. The functional connectivity (FC) of fMRI was assessed using a seed voxel linear correlation approach. The severity of aphasia was evaluated by aphasia quotient (AQ) scores obtained from Western Aphasia Battery test. Compared with normal subjects, aphasic patients showed decreased ALFF values in the regions of left posterior middle temporal gyrus (PMTG), left medial prefrontal gyrus, and right cerebellum. The ALFF values in left PMTG showed strong positive correlation with the AQ score (coefficient r =0.79, P temporal gyrus (BA20), fusiform gyrus (BA37), and inferior frontal gyrus (BA47\\45\\44). Left PMTG might play an important role in language dysfunction of chronic aphasia, and ALFF value might be a promising indicator to evaluate the severity of aphasia.

  1. Posterior Nutcracker Syndrome with Left Renal Vein Duplication: A Rare Cause of Haematuria in a 12-Year-Old Boy

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    J. Preza Fernandes

    2012-01-01

    Full Text Available The nutcracker syndrome (NCS is a rare cause of haematuria. It embraces an extended nonpathognomonic spectrum of symptoms that imply a difficult diagnosis. Ultimately it may be associated with substantial morbidity and even life-threatening events. We report a rare cause if a 12-year-old boy who presented with a history of frequent intermittent episodes of painless constant haematuria. The cystoscopy showed a bloody urine ejaculate from the left ureter meatus. The Doppler ultrasonography showed turbulent pattern of venous blood flow of the posterior renal vein branch behind the aorta. The abdominopelvic computer tomography (apCT revealed left renal vein (LRV duplication with a dilated retroaortic branch, entrapped between the aorta and the vertebral column, promoting the renal nutcracker syndrome. The patient was initially hospitalized and managed with oral iron supplements and continuous saline bladder irrigation, not requiring additional treatment. The child is currently asymptomatic, with haemoglobin value returning to normal and therefore proposed to conservative management with close followup. The authors present a case report of episodic haematuria caused by a rare entity—posterior nutcracker syndrome with renal vein duplication.

  2. Clinico-anatomical correlations of left posterior cerebral artery occlusion. Alexia without agraphia, color anomia, and memory disturbance

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    Isono, Osamu; Shiota, Junichi; Kawamura, Mitsuru; Hirayama, Keizou; Maki, Toshiyuki.

    1988-11-01

    The relation between neurological signs and symptoms and computed tomography (CT) and magnetic resonance imaging (MRI) was examined in 11 cases of occlusion of the left posterior cerebral artery. All the patients were righthanded. Right homonimous hemianopia was noted in 8 cases, right upper quadrantanopia in 2 cases, and right lower quadrantanopia in 1 case. Of the 11 cases, alexia without agraphia was noted in 9 cases, all 9 of which showed lesions of inferior occipital cortex (lingual and fusiform gyri) and subjacent white matter. Lesions of splenium were found in only 5 of the cases of alexia without agraphia. In 2 cases with neither alexia nor agraphia, lesions were seen in the medial occipital cortex and the subjacent white matter but not in the inferior occipital lobe. Three patients had color anomia which was accompanied by memory disturbances and alexia without agraphia. In 2 of these 3, lesions were widespread in the region of the left posterior cerebral artery. Memory disturbances were observed in 6 cases, all of which also showed alexia without agraphia. The lesions extended not only of the inferior surface of the occipital lobe and along the interhemispheric fissure, but also of hippocampal and parahippocampal gyri. In 3 cases of alexia without agraphia in which no memory distrubance was found, the symptoms of alexia were slight and disappeared at an early stage. (J.P.N.).

  3. Multimodal connectivity mapping of the human left anterior and posterior lateral prefrontal cortex.

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    Reid, Andrew T; Bzdok, Danilo; Langner, Robert; Fox, Peter T; Laird, Angela R; Amunts, Katrin; Eickhoff, Simon B; Eickhoff, Claudia R

    2016-06-01

    Working memory is essential for many of our distinctly human abilities, including reasoning, problem solving, and planning. Research spanning many decades has helped to refine our understanding of this high-level function as comprising several hierarchically organized components, some which maintain information in the conscious mind, and others which manipulate and reorganize this information in useful ways. In the neocortex, these processes are likely implemented by a distributed frontoparietal network, with more posterior regions serving to maintain volatile information, and more anterior regions subserving the manipulation of this information. Recent meta-analytic findings have identified the anterior lateral prefrontal cortex, in particular, as being generally engaged by working memory tasks, while the posterior lateral prefrontal cortex was more strongly associated with the cognitive load required by these tasks. These findings suggest specific roles for these regions in the cognitive control processes underlying working memory. To further characterize these regions, we applied three distinct seed-based methods for determining cortical connectivity. Specifically, we employed meta-analytic connectivity mapping across task-based fMRI experiments, resting-state BOLD correlations, and VBM-based structural covariance. We found a frontoparietal pattern of convergence which strongly resembled the working memory networks identified in previous research. A contrast between anterior and posterior parts of the lateral prefrontal cortex revealed distinct connectivity patterns consistent with the idea of a hierarchical organization of frontoparietal networks. Moreover, we found a distributed network that was anticorrelated with the anterior seed region, which included most of the default mode network and a subcomponent related to social and emotional processing. These findings fit well with the internal attention model of working memory, in which representation of

  4. The regional neuronal activity in left posterior middle temporal gyrus is correlated with the severity of chronic aphasia

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    Li J

    2017-07-01

    Full Text Available Jianlin Li,1,* Dunren Du,2,* Wei Gao,1 Xichun Sun,3 Haizhu Xie,1 Gang Zhang,1 Jian Li,1 Honglun Li,1 Kefeng Li4 1Department of Radiology, Yantai Yuhuangding Hospital, 2Department of Radiology, Yantai Laishan Branch Hospital of Yuhuangding Hospital, Medical College of Qingdao University, 3Department of Radiology, Yantai Hospital of Traditional Chinese Medicine, Yantai, China; 4School of Medicine, University of California, San Diego, CA, USA *These authors contributed equally to this work Background: Aphasia is one of the most disabling cognitive deficits affecting >2 million people in the USA. The neuroimaging characteristics of chronic aphasic patients (>6 months post onset remain largely unknown.Objective: The objective of this study was to investigate the regional signal changes of spontaneous neuronal activity of brain and the inter-regional connectivity in chronic aphasia. Materials and methods: Resting-state blood oxygenation level-dependent functional magnetic resonance imaging (fMRI was used to obtain fMRI data from 17 chronic aphasic patients and 20 healthy control subjects in a Siemens Verio 3.0T MR Scanner. The amplitude of low-frequency fluctuation (ALFF was determined, which directly reflects the regional neuronal activity. The functional connectivity (FC of fMRI was assessed using a seed voxel linear correlation approach. The severity of aphasia was evaluated by aphasia quotient (AQ scores obtained from Western Aphasia Battery test.Results: Compared with normal subjects, aphasic patients showed decreased ALFF values in the regions of left posterior middle temporal gyrus (PMTG, left medial prefrontal gyrus, and right cerebellum. The ALFF values in left PMTG showed strong positive correlation with the AQ score (coefficient r=0.79, P<0.05. There was a positive FC in chronic aphasia between left PMTG and left inferior temporal gyrus (BA20, fusiform gyrus (BA37, and inferior frontal gyrus (BA47\\45\\44. Conclusion: Left PMTG might play

  5. Atrial myocardium derives from the posterior region of the second heart field, which acquires left-right identity as Pitx2c is expressed.

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    Galli, Daniela; Domínguez, Jorge N; Zaffran, Stephane; Munk, Andrew; Brown, Nigel A; Buckingham, Margaret E

    2008-03-01

    Splanchnic mesoderm in the region described as the second heart field (SHF) is marked by Islet1 expression in the mouse embryo. The anterior part of this region expresses a number of markers, including Fgf10, and the contribution of these cells to outflow tract and right ventricular myocardium has been established. We now show that the posterior region also has myocardial potential, giving rise specifically to differentiated cells of the atria. This conclusion is based on explant experiments using endogenous and transgenic markers and on DiI labelling, followed by embryo culture. Progenitor cells in the right or left posterior SHF contribute to the right or left common atrium, respectively. Explant experiments with transgenic embryos, in which the transgene marks the right atrium, show that atrial progenitor cells acquire right-left identity between the 4- and 6-somite stages, at the time when Pitx2c is first expressed. Manipulation of Pitx2c, by gain- and loss-of-function, shows that it represses the transgenic marker of right atrial identity. A repressive effect is also seen on the proliferation of cells in the left sinus venosus and in cultured explants from the left side of the posterior SHF. This report provides new insights into the contribution of the SHF to atrial myocardium and the effect of Pitx2c on the formation of the left atrium.

  6. Varus deformity of the left lower extremity causing degenerative lesion of the posterior horn of the left medial meniscus in a patient with Paget’s disease of bone

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    Al Kaissi, Ali

    2014-09-01

    Full Text Available [english] We report on a 42-year-old woman who presented with persistent pain in her left knee with no history of trauma. Sagittal T1-weighted MRI of the left knee showed discontinuity between the anterior and posterior horns of the left medial meniscus, causing effectively the development of degenerative lesion of the posterior horn. The latter was correlated to varus deformity of the left lower extremity associated with subsequent narrowing of the medial knee joint. The unusual craniofacial contour of the patient, the skeletal survey and the elevated serum alkaline phosphatase were compatible with the diagnosis of Paget’s disease of the bone. To alleviate the adverse effect of the mal-alignment of the left femur onto the left knee, corrective osteotomy of the left femoral diaphysis by means of fixators was performed. To the best of our knowledge this is the first clinical report describing the management and the pathological correlation of a unilateral varus deformity of the femoral shaft and degenerative lesions of the left knee in a patient with Paget’s disease of the bone.

  7. A case of left-sided unilateral spatial neglect owing to the cerebral infarction in the distribution of the right posterior cerebral artery

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    Odagaki, Yuji; Oka, Iori; Kon, Yutaka; Asano, Yutaka

    1985-01-01

    We report a case of left-sided unilateral spatial neglect (USN) induced by the cerebral infarction in the distribution of right posterior cerebral artery (PCA). A 69-year-old, right-handed man, who had had a sudden onset of left hemiparesis in August 1983, was admitted to our hospital on January 16, 1984, because of nocturnal delirium. He became alert a few days after admission, but was euphoric and sometimes irritable. Neurologic examination disclosed left homonymous hemianopsia, dysarthria, left central facial weakness, spastic left hemiparesis, hyperactive reflexes on the left with no Babinski sign, left hemisensory loss, and left thalamic pain. On neuropsychologic examination it was revealed that he had a tendency to neglect the left half of his extrapersonal space. When asked to locate cities on a blank map of Japan, he located most of them not only on the right side of the map but also incorrectly. He also had a severe acalculia. There was gradual improvement in these neuropsychologic symptoms. CT demonstrated an area of decreased density in the territory of the right PCA, posterolateral portion of the right thalamus, and the posterior limb of right internal capsule, sparing parietal and temporal lobes. Single-photon emission computed tomography (SPECT) using the Xenon-133 inhalation method showed, however, diminished regional cerebral blood flow (rCBF) in an area larger than the area of infarction demonstrated by CT, including the right parieto-temporo-occipital junctional area, which has been considerd to be responsible for left-sided USN. The authors ascribed the patient's left-sided USN to the lesion of this area that was revealed not morphologically by CT but functionally by SPECT, although the possibility that the lesions of the medial portion of the right occipital lobe and/or subcortical lesions of such areas as the thalamus and the internal capsule more or less influenced the neuropsychologic symptoms could not be excluded. (author)

  8. Right-to-left shunt may be prone to affect the white matter integrity of posterior circulation in migraine without aura.

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    Xie, Hui; Bian, Yitong; Jian, Zhijie; Huo, Kang; Liu, Rui; Zhu, Dan; Zhang, Lihui; Wu, Jun; Yang, Jian; Liu, Jixin; Luo, Guogang

    2018-01-01

    Numerous studies have indicated an association between migraine and right-to-left shunt. However, little is known about whether right-to-left shunt has an effect on the migraine brain. This observational study aims to explore the impact of right-to-left shunt on the brain of migraine without aura on microstructural level. Thirty-five patients with migraine without aura were enrolled in this study. Contrast-enhanced Transcranial Doppler was performed to evaluate the status of right-to-left shunt. Three-dimensional T1-weighted and diffusion tensor images were acquired for data analysis. We employed voxel-based morphometry and tract-based spatial statistical analyses to assess the differences of gray and white matter between migraineurs with and without right-to-left shunt, respectively. Among the 35 patients, 19 (54.3%) patients had right-to-left shunt. There were no significant differences in headache features between migraineurs with and without right-to-left shunt. There were significant increases of mean and radial diffusivity in migraineurs with right-to-left shunt compared with migraineurs without right-to-left shunt. The alterations were primarily located in the right posterior thalamic radiation, secondly in the body of corpus callosum and the right superior corona radiata. No significant differences were observed in values of fractional anisotropy and axial diffusivity. No significant between-group differences were found in gray matter volume. Right-to-left shunt may cause alterations of white matter integrity in migraine without aura, and the alterations are more likely to be located at the posterior circulation.

  9. Catheter Ablation of Idiopathic Left Posterior Fascicular Ventricular Tachycardia: Predicting the Site of Origin via Mapping and Electrocardiography.

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    Ma, Wei; Lu, Fengmin; Shehata, Michael; Wang, Xunzhang; Zhang, Fan; Chen, Bingwei; Wu, Dongyan; He, Le; Sun, Shan; Cheng, Aijuan; Ding, Jun; Cong, Hongliang; Xu, Jing

    2017-11-01

    We report the 12-lead ECG morphology of left posterior fascicular ventricular tachycardia (LPF-VT) and the relationship between His-ventricular (HV) interval and site of origin in LPF-VT. We studied 41 patients who underwent successful catheter ablation of LPF-VT with HV interval >0 ms (n=8; proximal-LPF group), HV interval 0 to -15 ms (n=15; middle-LPF group), and HV interval <-15 ms (n=18; distal-LPF group). The earliest mapped presystolic potential (PP)-QRS interval was 34.1±4.2, 24.5±3.2, and 19.4±2.8 ms in proximal-, middle-, and distal-LPF groups. The earliest PP ratio (PP-QRS interval during VT/HV interval during sinus rhythm) was 0.59±0.05, 0.45±0.07, and 0.31±0.05 in the proximal-, middle-, and distal-LPF groups. There were statistically significant differences between the 3 groups in earliest PP ratio, and there was close correlation between the HV interval during LPF-VT and earliest PP ratio. The QRS duration in the proximal-LPF group (114±6 ms) was significantly narrower compared with the middle-LPF group (128±5 ms) and distal-LPF group (140±6 ms). In leads I and V6, the ratio of R/S tended to be greater in the proximal-LPF group compared with the other 2 groups. QRS duration, the ratio of R/S in leads V6, and lead I could predict a proximal or distal origin site of LPF-VT with high sensitivity and specificity. The HV interval and 12-lead ECG morphology of LPF-VT may help predict the successful site of origin and prove useful in guiding an effective ablation strategy. © 2017 American Heart Association, Inc.

  10. Left posterior-dorsal area 44 couples with parietal areas to promote speech fluency, while right area 44 activity promotes the stopping of motor responses.

    Science.gov (United States)

    Neef, Nicole E; Bütfering, Christoph; Anwander, Alfred; Friederici, Angela D; Paulus, Walter; Sommer, Martin

    2016-11-15

    Area 44 is a cytoarchitectonically distinct portion of Broca's region. Parallel and overlapping large-scale networks couple with this region thereby orchestrating heterogeneous language, cognitive, and motor functions. In the context of stuttering, area 44 frequently comes into focus because structural and physiological irregularities affect developmental trajectories, stuttering severity, persistency, and etiology. A remarkable phenomenon accompanying stuttering is the preserved ability to sing. Speaking and singing are connatural behaviours recruiting largely overlapping brain networks including left and right area 44. Analysing which potential subregions of area 44 are malfunctioning in adults who stutter, and what effectively suppresses stuttering during singing, may provide a better understanding of the coordination and reorganization of large-scale brain networks dedicated to speaking and singing in general. We used fMRI to investigate functionally distinct subregions of area 44 during imagery of speaking and imaginary of humming a melody in 15 dextral males who stutter and 17 matched control participants. Our results are fourfold. First, stuttering was specifically linked to a reduced activation of left posterior-dorsal area 44, a subregion that is involved in speech production, including phonological word processing, pitch processing, working memory processes, sequencing, motor planning, pseudoword learning, and action inhibition. Second, functional coupling between left posterior area 44 and left inferior parietal lobule was deficient in stuttering. Third, despite the preserved ability to sing, males who stutter showed bilaterally a reduced activation of area 44 when imagine humming a melody, suggesting that this fluency-enhancing condition seems to bypass posterior-dorsal area 44 to achieve fluency. Fourth, time courses of the posterior subregions in area 44 showed delayed peak activations in the right hemisphere in both groups, possibly signaling the

  11. The anodal tDCS over the left posterior parietal cortex enhances attention toward a focus word in a sentence.

    Science.gov (United States)

    Minamoto, Takehiro; Azuma, Miyuki; Yaoi, Ken; Ashizuka, Aoi; Mima, Tastuya; Osaka, Mariko; Fukuyama, Hidenao; Osaka, Naoyuki

    2014-01-01

    The posterior parietal cortex (PPC) has two attentional functions: top-down attentional control and stimulus-driven attentional processing. Using the focused version of the reading span test (RST), in which the target word to be remembered is the critical word for comprehending a sentence (focused word) or a non-focused word, we examined the effect of tDCS on resolution of distractor interference by the focused word in the non-focus condition (top-down attentional control) and on augmented/shrunk attentional capture by the focused word in both the focus and non-focus conditions (stimulus-driven attentional processing). Participants were divided into two groups: anodal tDCS (atDCS) and cathodal tDCS (ctDCS). Online stimulation was given while participants performed the RST. A post-hoc recognition task was also administered in which three kinds of words were presented: target words in the RST, distractor words in the RST, and novel words. atDCS augmented the effect of the focused word by increasing differences in performance between the focus and non-focus conditions. Such an effect was not observed in the ctDCS group. As for the recognition task, atDCS again produced the augmented effect of the focused words in the distractor recognition. On the other hand, ctDCS brought less recognition of non-focused target words in comparison to sham. The results indicate that atDCS promotes stimulus-driven attentional processing, possibly by affecting neural firing in the inferior parietal regions. In contrast, ctDCS appears to prevent retrieval of less important information from episodic memory, which may require top-down attentional processing.

  12. TMS interferes with lexical-semantic retrieval in left inferior frontal gyrus and posterior middle temporal gyrus: Evidence from cyclical picture naming.

    Science.gov (United States)

    Krieger-Redwood, Katya; Jefferies, Elizabeth

    2014-11-01

    We used TMS to investigate the contribution of left inferior frontal gyrus (LIFG) and posterior middle temporal gyrus (pMTG) to lexical/semantic selection and retrieval processes using a cyclical naming paradigm. Participants named pictures that were presented repeatedly across six cycles, either in semantically related or unrelated sets. Previous research has suggested that selection demands are higher for related sets, especially after repetition, since participants experience competition from the activation of semantic neighbours. In contrast, retrieval demands are greater for unrelated sets in the absence of semantic priming, particularly on the first cycle when the target names have not been previously activated. Therefore, this paradigm can reveal independent effects of (i) retrieval demands (i.e., the ease of accessing picture names from visual input) and (ii) selection/competition. We found that rTMS to LIFG and pMTG produced similar behavioural effects: stimulation of both sites disrupted picture naming performance on early cycles (when participants were less practised at producing the picture names) and for semantically-related sets (when there was the potential for increased competition and yet also facilitation from semantic neighbours). There were no effects of TMS when either retrieval or selection requirements were maximal on their own. The data therefore support the view that both LIFG and pMTG contribute to picture name retrieval, with both sites playing a critical role in mediating the semantic facilitation of naming when retrieval demands are high. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Context-dependent lexical ambiguity resolution: MEG evidence for the time-course of activity in left inferior frontal gyrus and posterior middle temporal gyrus.

    Science.gov (United States)

    Mollo, Giovanna; Jefferies, Elizabeth; Cornelissen, Piers; Gennari, Silvia P

    An MEG study investigated the role of context in semantic interpretation by examining the comprehension of ambiguous words in contexts leading to different interpretations. We compared high-ambiguity words in minimally different contexts (to bowl, the bowl) to low-ambiguity counterparts (the tray, to flog). Whole brain beamforming revealed the engagement of left inferior frontal gyrus (LIFG) and posterior middle temporal gyrus (LPMTG). Points of interest analyses showed that both these sites showed a stronger response to verb-contexts by 200 ms post-stimulus and displayed overlapping ambiguity effects that were sustained from 300 ms onwards. The effect of context was stronger for high-ambiguity words than for low-ambiguity words at several different time points, including within the first 100 ms post-stimulus. Unlike LIFG, LPMTG also showed stronger responses to verb than noun contexts in low-ambiguity trials. We argue that different functional roles previously attributed to LIFG and LPMTG are in fact played out at different periods during processing. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

  14. Defeito do anel fibroso mitral posterior com aneurisma de átrio esquerdo e insuficiência mitral: tratamento cirúrgico com sucesso Defect of the posterior mitral fibrous ring with left atrial aneurysm and mitral insufficiency: successful surgical treatment

    Directory of Open Access Journals (Sweden)

    Ronaldo Machado BUENO

    1999-10-01

    Full Text Available Aneurismas em átrio esquerdo são pouco comuns, podendo ocorrer na aurícula ou na parede do átrio esquerdo. Freqüentemente, são assintomáticos, podendo ocorrer arritmias, fenômenos tromboembólicos ou insuficiência cardíaca como complicação da sua evolução. Apresentamos paciente de 39 anos, do sexo feminino, com defeito do anel posterior da valva mitral levando a grande dilatação aneurismática da parede posterior do átrio esquerdo com insuficiência mitral. O diagnóstico foi feito pela radiografia de tórax (abaulamento de silhueta cardíaca esquerda e ecocardiograma (grande aneurisma do átrio esquerdo posteriormente à parede posterior do ventrículo esquerdo com insuficiência mitral. O estudo hemodinâmico sugeriu pseudo-aneurisma de ventrículo esquerdo. Submetida a tratamento cirúrgico com auxílio da circulação extracorpórea, realizou-se anuloplastia mitral e exclusão do aneurisma com reconstrução do assoalho do átrio esquerdo com retalho de pericárdio bovino. A paciente apresentou boa evolução pós-operatória, recebendo alta hospitalar no oitavo dia em boas condições clínicas.Atrial aneurysm is a rare condition and can be found on the atrial appendage or on the atrial wall. Most patients are asymptomatic, but arrhythmias, thromboembolism, and heart failure are common complications. We present a 39 years old female patient with posterior mitral ring defect causing a great aneurysm of the left posterior atrial wall with mitral insufficiency. The diagnosis was achieved by chest roentgenogram (marked prominence of the upper left heart border and echocardiography (great left atrial aneurysm behind the left posterior ventricular wall with mitral insufficiency. Left ventricular cineangiogram suggested the presence of a false aneurysm of the left ventricle. The patient subsequently underwent surgical treatment with cardiopulmonary bypass. Posterior mitral valve annuloplasty was performed with aneurysm exclusion

  15. The left visual-field advantage in rapid visual presentation is amplified rather than reduced by posterior-parietal rTMS

    DEFF Research Database (Denmark)

    Verleger, Rolf; Möller, Friderike; Kuniecki, Michal

    2010-01-01

    In the present task, series of visual stimuli are rapidly presented left and right, containing two target stimuli, T1 and T2. In previous studies, T2 was better identified in the left than in the right visual field. This advantage of the left visual field might reflect dominance exerted...... by the right over the left hemisphere. If so, then repetitive transcranial magnetic stimulation (rTMS) to the right parietal cortex might release the left hemisphere from right-hemispheric control, thereby improving T2 identification in the right visual field. Alternatively or additionally, the asymmetry in T2......) either as effective or as sham stimulation. In two experiments, either one of these two factors, hemisphere and effectiveness of rTMS, was varied within or between participants. Again, T2 was much better identified in the left than in the right visual field. This advantage of the left visual field...

  16. Efficient visual object and word recognition relies on high spatial frequency coding in the left posterior fusiform gyrus: evidence from a case-series of patients with ventral occipito-temporal cortex damage.

    Science.gov (United States)

    Roberts, Daniel J; Woollams, Anna M; Kim, Esther; Beeson, Pelagie M; Rapcsak, Steven Z; Lambon Ralph, Matthew A

    2013-11-01

    Recent visual neuroscience investigations suggest that ventral occipito-temporal cortex is retinotopically organized, with high acuity foveal input projecting primarily to the posterior fusiform gyrus (pFG), making this region crucial for coding high spatial frequency information. Because high spatial frequencies are critical for fine-grained visual discrimination, we hypothesized that damage to the left pFG should have an adverse effect not only on efficient reading, as observed in pure alexia, but also on the processing of complex non-orthographic visual stimuli. Consistent with this hypothesis, we obtained evidence that a large case series (n = 20) of patients with lesions centered on left pFG: 1) Exhibited reduced sensitivity to high spatial frequencies; 2) demonstrated prolonged response latencies both in reading (pure alexia) and object naming; and 3) were especially sensitive to visual complexity and similarity when discriminating between novel visual patterns. These results suggest that the patients' dual reading and non-orthographic recognition impairments have a common underlying mechanism and reflect the loss of high spatial frequency visual information normally coded in the left pFG.

  17. Posterior Elbow Dislocation

    Directory of Open Access Journals (Sweden)

    Victoria Oppenheim

    2016-09-01

    Full Text Available History of present illness: A 15-year old female presented with left elbow pain. While competing in a high school wrestling match, she extended her left arm to brace a fall and had immediate onset of sharp pain. She denied weakness or numbness of her left arm. She had no past medical history. Significant findings: Elbow dislocations are classified by the position of the radio-ulnar joint relative to the humerus.1 Images 1, 2, and 3 show a left posterior elbow dislocation; the radius and ulna are displaced posteriorly with respect to the distal humerus. The lateral view of the elbow most clearly shows this: trochlear notch of the ulna is empty and displaced posteriorly relative to the trochlea. There is no associated fracture. Images 4 and 5 show the elbow status-post reduction, demonstrating proper alignment of the distal humerus with the radius and ulna. Discussion: Traumatic dislocations of the elbow are relatively uncommon in pediatric patients, with a peak incidence at 13 to 14 years.1 Dislocations are usually posterior and occur after forced abduction and extension of the elbow.1 It is important to evaluate for an associated fracture or avulsion, which occurs in over 50% of pediatric elbow dislocations. Fractures most commonly involve the medial epicondyle, radial head and neck, or coronoid process.1 One should also consider a neurovascular injury to the ulnar or median nerve or to the brachial artery or its branches.1 Posterior elbow dislocations should be reduced as soon as possible.1 Patients should receive adequate sedation and/or analgesia. One method of reduction is the “puller” technique, during which a practitioner stabilizes the humerus, while a second practitioner applies force against the anterior forearm, with gentle traction distally.1 Post-reduction neurovascular reassessment is important. After successful reduction, patients can be immobilized in a posterior long arm splint.

  18. Hippocampus discovery First steps

    Directory of Open Access Journals (Sweden)

    Eliasz Engelhardt

    Full Text Available The first steps of the discovery, and the main discoverers, of the hippocampus are outlined. Arantius was the first to describe a structure he named "hippocampus" or "white silkworm". Despite numerous controversies and alternate designations, the term hippocampus has prevailed until this day as the most widely used term. Duvernoy provided an illustration of the hippocampus and surrounding structures, considered the first by most authors, which appeared more than one and a half century after Arantius' description. Some authors have identified other drawings and texts which they claim predate Duvernoy's depiction, in studies by Vesalius, Varolio, Willis, and Eustachio, albeit unconvincingly. Considering the definition of the hippocampal formation as comprising the hippocampus proper, dentate gyrus and subiculum, Arantius and Duvernoy apparently described the gross anatomy of this complex. The pioneering studies of Arantius and Duvernoy revealed a relatively small hidden formation that would become one of the most valued brain structures.

  19. Tratamento cirúrgico da fibrilação atrial por isolamento da parede posterior do átrio esquerdo em doentes com valvopatia mitral reumática crônica: um estudo randomizado com grupo controle Surgical treatment of atrial fibrillation through isolation of the left atrial posterior wall in patients with chronic rheumatic mitral valve disease: a randomized study with control group

    Directory of Open Access Journals (Sweden)

    José Tarcísio Medeiros de Vasconcelos

    2004-09-01

    Full Text Available OBJETIVO: Determinar a efetividade do isolamento cirúrgico da parede posterior do átrio esquerdo envolvendo os óstios das veias pulmonares, no tratamento da fibrilação atrial de etiologia reumática. MÉTODOS: Estudo prospectivo e randomizado envolvendo portadores de valvopatia mitral reumática, fibrilação atrial persistente com duração > a 6 meses, idade OBJECTIVE: To determine the effectiveness of surgical isolation of the left atrial posterior wall encompassing the ostia of the pulmonary veins for the treatment of atrial fibrillation of rheumatic etiology. METHODS: Prospective and randomized study of patients with rheumatic mitral valve disease, persistent atrial fibrillation for 6 months or longer, age < 60 years, and left atrial diameter < 65 mm. The patients were randomly distributed into 2 groups as follows: surgical valvular treatment (control group and surgical valvular treatment associated with isolation of the left atrial posterior wall according to the "cut-and-sew" technique (treated group. RESULTS: Twenty-nine individuals were operated upon, 27 of whom (13 in the control group and 14 in the treated group were regularly followed up. The patients of both groups did not differ in regard to their basal characteristics. The mean follow-up time was 11.5 months in the control group and 10.3 months in the treated group. The cumulative frequencies of the patients without atrial fibrillation were significantly greater in the treated group both in the perioperative (P=0.0035 and late (P=0.0430 phases. CONCLUSION: Surgical isolation of the left atrial posterior wall encompassing the ostia of the pulmonary veins is an effective form of treating atrial fibrillation in rheumatic mitral valve disease.

  20. Hippocampus and consciousness.

    Science.gov (United States)

    Behrendt, Ralf-Peter

    2013-01-01

    An important assumption concerning the physiology of consciousness is that all varieties of conscious experience are closely related to each other and, hence, are subserved by the same neural mechanism. There are several considerations that lead us to implicate the hippocampus in the generation of conscious perception and, ultimately, of conscious experiences of all kinds. Firstly, conscious perception of external events is intricately linked with the formation of episodic (declarative) memories, a key function attributed to the hippocampus. Secondly, conscious experience is allocentric and contextualized. Consciousness creates or simulates an image of the world that appears to surround us and to be independent of our observation of it. What is characteristic of wakeful consciousness and dreaming alike is that objects or events are experienced as being embedded in an external, that is, allocentric, frame of space and time. The hippocampus has been implicated in the rapid formation and memorization of allocentric representations that embed objects or events in a world context. Thirdly, the hippocampus is ideally positioned to bind information processed in different sensory association cortices. It is argued that rapidly forming patterns of neuronal ensemble firing in the hippocampus, particularly in region CA3, which encode arbitrary associations between objects and their spatiotemporal and emotional context, that is, associations between information derived from different neocortical processing streams, define the informational content of consciousness. Evidence suggestive of an important contribution of the hippocampus to conscious observation, mental imagery, dreaming, conscious anticipation of outcomes, and hallucinations will be reviewed.

  1. The hippocampus - pictorial essay

    International Nuclear Information System (INIS)

    Whan, A.; Mitchell, L.A.

    2002-01-01

    Full text: We aim to demonstrate the anatomy and pathology of the hippocampus. It is important that radiologists distinguish normal and abnormal hippocampal hippocampal MR appearances, since hippocampal sclerosis is the commonest cause of surgically treatable temporal lobe epilepsy. The detailed anatomy of the hippocampus is reviewed and correlated with normal MR appearances. Our radiology database was reviewed to determine both common and unusual pathologies affecting the hippocampus. Most scans were performed for our large Comprehensive Epilepsy Program, for investigation of epilepsy of possible seizures. Less frequent indications included memory loss (acute or chronic), stroke, headache, and altered conscious state. Hippocampal sclerosis was the commonest MR abnormality. This was occasionally bilateral or associated with other pathology. Other common findings included mild hippocampal asymmetry, bilateral atrophy, or normal variants such as choroid fissure cysts. Other pathologies included cortical developmental malformations, infarction, posttraumatic gliosis, herpes, simplex encephalitis, paraneoplastic limbic encephalitis, vascular malformations, sarcoidosis, benign tumours such as gangliogliomas and dysembyoplastic neuroepithelial tumours (DNET) and malignant tumours. The hippocampus has a complex anatomy visible on high resolution MRI. In the clinical context of epilepsy, hippocampal sclerosis is an important pathology, but a range of conditions may affect the hippocampus, readily demonstrated by MRI. Copyright (2002) Blackwell Science Pty Ltd

  2. Serotonin Receptors in Hippocampus

    Science.gov (United States)

    Berumen, Laura Cristina; Rodríguez, Angelina; Miledi, Ricardo; García-Alcocer, Guadalupe

    2012-01-01

    Serotonin is an ancient molecular signal and a recognized neurotransmitter brainwide distributed with particular presence in hippocampus. Almost all serotonin receptor subtypes are expressed in hippocampus, which implicates an intricate modulating system, considering that they can be localized as autosynaptic, presynaptic, and postsynaptic receptors, even colocalized within the same cell and being target of homo- and heterodimerization. Neurons and glia, including immune cells, integrate a functional network that uses several serotonin receptors to regulate their roles in this particular part of the limbic system. PMID:22629209

  3. Connectivity of the hippocampus and Broca's area during acquisition of a novel grammar.

    Science.gov (United States)

    Kepinska, Olga; de Rover, Mischa; Caspers, Johanneke; Schiller, Niels O

    2018-01-15

    Following Opitz and Friederici (2003) suggesting interactions of the hippocampal system and the prefrontal cortex as the neural mechanism underlying novel grammar learning, the present fMRI study investigated functional connectivity of bilateral BA 44/45 and the hippocampus during an artificial grammar learning (AGL) task. Our results, contrary to the previously reported interactions, demonstrated parallel (but separate) contributions of both regions, each with their own interactions, to the process of novel grammar acquisition. The functional connectivity pattern of Broca's area pointed to the importance of coherent activity of left frontal areas around the core language processing region for successful grammar learning. Furthermore, connectivity patterns of left and right hippocampi (predominantly with occipital areas) were found to be a strong predictor of high performance on the task. Finally, increasing functional connectivity over time of both left and right BA 44/45 with the right posterior cingulate cortex and the right temporo-parietal areas points to the importance of multimodal and attentional processes supporting novel grammar acquisition. Moreover, it highlights the right-hemispheric involvement in initial stages of L2 learning. These latter interactions were found to operate irrespective of the task performance, making them an obligatory mechanism accompanying novel grammar learning. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Identification of the fetal hippocampus and fornix and role of 3-dimensional sonography.

    Science.gov (United States)

    Gindes, Liat; Weissmann-Brenner, Alina; Weisz, Boaz; Zajicek, Michal; Geffen, Keren Tzadikevitch; Achiron, Reuven

    2011-12-01

    The purposes of this study were to identify the fetal hippocampus and fornix using 3-dimensional sonography, to measure their curved length during pregnancy, and to describe a systematic method for volume data set analysis of the fetal hippocampus and fornix. Three-dimensional volumes of the fetal brain were acquired prospectively in 34 patients between 14 and 37 weeks' gestation. Volumes were acquired with trans-abdominal and transvaginal transducers. All volumes were analyzed offline by 2 examiners separately. The feasibility of identifying the fetal hippocampus and fornix was analyzed. The curved length of the hippocampus-fornix structure was measured on the right and left hemispheres. The fetal hippocampus and fornix were identified bilaterally in 32 of 34 fetuses (94%) at gestational ages of 14 weeks 5 days to 37 weeks 1 day (mean, 23 weeks 3 days). In 1 fetus (3%), only one side was shown, and in another fetus (3%), both sides were obscured by acoustic shadows. A systematic approach for identification of the fetal hippocampus is described. Linear growth of the fetal hippocampus and fornix was shown during pregnancy and was correlated with both the gestational week and the head circumference (R = 0.71 and 0.74, respectively; P = .01). The length of the hippocampus and fornix did not differ between the left and the right hemispheres (P = .598). The fetal hippocampus and fornix can be identified by a systematic analysis of 3-dimensional data set volumes. The normal hippocampus and fornix show linear growth throughout pregnancy.

  5. Left ventricular hypertrophy in athletes.

    Science.gov (United States)

    Douglas, P S; O'Toole, M L; Katz, S E; Ginsburg, G S; Hiller, W D; Laird, R H

    1997-11-15

    Left ventricular wall thickness >1.3 cm, septal-to-posterior wall ratios > 1.5, diastolic left ventricular size >6.0 cm, and eccentric or concentric remodeling are rare in athletes. Values outside of these cutoffs in an athlete of any age probably represent a pathologic state.

  6. Clinical correlates of hippocampus volume and shape in antipsychotic-naïve schizophrenia.

    Science.gov (United States)

    Kalmady, Sunil Vasu; Shivakumar, Venkataram; Arasappa, Rashmi; Subramaniam, Aditi; Gautham, S; Venkatasubramanian, Ganesan; Gangadhar, Bangalore N

    2017-05-30

    While volume deficit of hippocampus is an established finding in schizophrenia, very few studies have examined large sample of patients without the confounding effect of antipsychotic treatment. Concurrent evaluation of hippocampus shape will offer additional information on the hippocampal aberrations in schizophrenia. In this study, we analyzed the volume and shape of hippocampus in antipsychotic-naïve schizophrenia patients (N=71) in comparison to healthy controls (N=82). Using 3-T MRI data, gray matter (GM) volume (anterior and posterior sub-divisions) and shape of the hippocampus were analyzed. Schizophrenia patients had significant hippocampal GM volume deficits (specifically the anterior sub-division) in comparison to healthy controls. There were significant positive correlations between anterior hippocampus volume and psychopathology scores of positive syndrome. Shape analyses revealed significant inward deformation of bilateral hippocampal surface in patients. In conclusion, our study findings add robust support for volume deficit in hippocampus in antipsychotic-naïve schizophrenia. Hippocampal shape deficits in schizophrenia observed in this study map to anterior CA1 sub-region. The differential relationship of anterior hippocampus (but not posterior hippocampus) with clinical symptoms is in tune with the findings in animal models. Further systematic studies are needed to evaluate the relationship between these hippocampal gray matter deficits with white matter and functional connectivity to facilitate understanding the hippocampal network abnormalities in schizophrenia. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  7. The Anterior Prefrontal Cortex and the Hippocampus Are Negatively Correlated during False Memories.

    Science.gov (United States)

    Jeye, Brittany M; Karanian, Jessica M; Slotnick, Scott D

    2017-01-23

    False memories commonly activate the anterior/dorsolateral prefrontal cortex (A/DLPFC) and the hippocampus. These regions are assumed to work in concert during false memories, which would predict a positive correlation between the magnitudes of activity in these regions across participants. However, the A/DLPFC may also inhibit the hippocampus, which would predict a negative correlation between the magnitudes of activity in these regions. In the present functional magnetic resonance imaging (fMRI) study, during encoding, participants viewed abstract shapes in the left or right visual field. During retrieval, participants classified each old shape as previously in the "left" or "right" visual field followed by an "unsure"-"sure"-"very sure" confidence rating. The contrast of left-hits and left-misses produced two activations in the hippocampus and three activations in the left A/DLPFC. For each participant, activity associated with false memories (right-"left"-"very sure" responses) from the two hippocampal regions was plotted as a function of activity in each A/DLPFC region. Across participants, for one region in the left anterior prefrontal cortex, there was a negative correlation between the magnitudes of activity in this region and the hippocampus. This suggests that the anterior prefrontal cortex might inhibit the hippocampus during false memories and that participants engage either the anterior prefrontal cortex or the hippocampus during false memories.

  8. Progressive posterior cortical dysfunction

    Directory of Open Access Journals (Sweden)

    Fábio Henrique de Gobbi Porto

    Full Text Available Abstract Progressive posterior cortical dysfunction (PPCD is an insidious syndrome characterized by prominent disorders of higher visual processing. It affects both dorsal (occipito-parietal and ventral (occipito-temporal pathways, disturbing visuospatial processing and visual recognition, respectively. We report a case of a 67-year-old woman presenting with progressive impairment of visual functions. Neurologic examination showed agraphia, alexia, hemispatial neglect (left side visual extinction, complete Balint's syndrome and visual agnosia. Magnetic resonance imaging showed circumscribed atrophy involving the bilateral parieto-occipital regions, slightly more predominant to the right . Our aim was to describe a case of this syndrome, to present a video showing the main abnormalities, and to discuss this unusual presentation of dementia. We believe this article can contribute by improving the recognition of PPCD.

  9. Reversible posterior leukoencephalopathy syndrome

    International Nuclear Information System (INIS)

    Lee, Eun Ja; Yu, Won Jong; Ahn, Kook Jin; Jung, So Lyung; Lee, Yeon Soo; Kim, Ji Chang; Kang, Si Won; Song, Chang Joon; Song, Soon-Young; Koo, Ja Hong; Kim, Man Deuk

    2001-01-01

    To review reversible posterior leukoencephalopathy syndrome. We reviewed 22 patients (M:F=3:19; age, 17-46 years) with the characteristic clinical and imaging features of reversible posterior leukoencephalopathy syndrome. All underwent brain MRI, and in three cases both CT and MRI were performed. In one, MRA was obtained, and in eleven, follow-up MR images were obtained. We evaluated the causes of this syndrome, its clinical manifestations, and MR findings including the locations of lesions, the presence or absence of contrast enhancement, and the changes seen at follow-up MRI. Of the 22 patients, 13 had eclampsia (six during pregnancy and seven during puerperium). Four were receiving immunosuppressive therapy (three, cyclosporine ; one, FK 506). Four suffered renal failure and one had complicated migraine. The clinical manifestations included headache (n=12), visual disturbance (n=13), seizure (n=15), focal neurologic sign (n=3), and altered mental status (n=2). Fifteen patients had hypertension and the others normotension. MRI revealed that lesions were bilateral (n=20) or unilateral (n=2). In all patients the lesion was found in the cortical and subcortical areas of the parieto-occipital lobes ; other locations were the basal ganglia (n=9), posterior temporal lobe (n=8), frontal lobe (n=5), cerebellum (n=5), pons (n=2), and thalamus (n=1). All lesions were of high signal intensity on T2-weighted images, and of iso to low intensity on T1-weighted images. One was combined with acute hematoma in the left basal ganglia. In eight of 11 patients who underwent postcontrast T1-weighted MRI, there was no definite enhancement ; in one, enhancement was mild, and in tow, patchy. CT studies showed low attenuation, and MRA revealed mild vasospasm. The symptoms of all patients improved. Follow-up MRI in nine of 11 patients depicted complete resolution of the lesions ; in two, small infarctions remained but the extent of the lesions had decreased. Reversible posterior

  10. Reversible posterior leukoencephalopathy syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Ja; Yu, Won Jong; Ahn, Kook Jin; Jung, So Lyung; Lee, Yeon Soo; Kim, Ji Chang; Kang, Si Won [The Catholic Univ. of Korea, Taejon (Korea, Republic of); Song, Chang Joon [Chungnam National Univ. School of Medicine, Cheonju (Korea, Republic of); Song, Soon-Young; Koo, Ja Hong [Kwandong Univ. College of Medicine, Myungji Hospital, Seoul (Korea, Republic of); Kim, Man Deuk [College of Medicine Pochon CHA Univ., Seoul (Korea, Republic of)

    2001-10-01

    To review reversible posterior leukoencephalopathy syndrome. We reviewed 22 patients (M:F=3:19; age, 17-46 years) with the characteristic clinical and imaging features of reversible posterior leukoencephalopathy syndrome. All underwent brain MRI, and in three cases both CT and MRI were performed. In one, MRA was obtained, and in eleven, follow-up MR images were obtained. We evaluated the causes of this syndrome, its clinical manifestations, and MR findings including the locations of lesions, the presence or absence of contrast enhancement, and the changes seen at follow-up MRI. Of the 22 patients, 13 had eclampsia (six during pregnancy and seven during puerperium). Four were receiving immunosuppressive therapy (three, cyclosporine ; one, FK 506). Four suffered renal failure and one had complicated migraine. The clinical manifestations included headache (n=12), visual disturbance (n=13), seizure (n=15), focal neurologic sign (n=3), and altered mental status (n=2). Fifteen patients had hypertension and the others normotension. MRI revealed that lesions were bilateral (n=20) or unilateral (n=2). In all patients the lesion was found in the cortical and subcortical areas of the parieto-occipital lobes ; other locations were the basal ganglia (n=9), posterior temporal lobe (n=8), frontal lobe (n=5), cerebellum (n=5), pons (n=2), and thalamus (n=1). All lesions were of high signal intensity on T2-weighted images, and of iso to low intensity on T1-weighted images. One was combined with acute hematoma in the left basal ganglia. In eight of 11 patients who underwent postcontrast T1-weighted MRI, there was no definite enhancement ; in one, enhancement was mild, and in tow, patchy. CT studies showed low attenuation, and MRA revealed mild vasospasm. The symptoms of all patients improved. Follow-up MRI in nine of 11 patients depicted complete resolution of the lesions ; in two, small infarctions remained but the extent of the lesions had decreased. Reversible posterior

  11. The Anterior Prefrontal Cortex and the Hippocampus Are Negatively Correlated during False Memories

    Directory of Open Access Journals (Sweden)

    Brittany M. Jeye

    2017-01-01

    Full Text Available False memories commonly activate the anterior/dorsolateral prefrontal cortex (A/DLPFC and the hippocampus. These regions are assumed to work in concert during false memories, which would predict a positive correlation between the magnitudes of activity in these regions across participants. However, the A/DLPFC may also inhibit the hippocampus, which would predict a negative correlation between the magnitudes of activity in these regions. In the present functional magnetic resonance imaging (fMRI study, during encoding, participants viewed abstract shapes in the left or right visual field. During retrieval, participants classified each old shape as previously in the “left” or “right” visual field followed by an “unsure”–“sure”–“very sure” confidence rating. The contrast of left-hits and left-misses produced two activations in the hippocampus and three activations in the left A/DLPFC. For each participant, activity associated with false memories (right–“left”–“very sure” responses from the two hippocampal regions was plotted as a function of activity in each A/DLPFC region. Across participants, for one region in the left anterior prefrontal cortex, there was a negative correlation between the magnitudes of activity in this region and the hippocampus. This suggests that the anterior prefrontal cortex might inhibit the hippocampus during false memories and that participants engage either the anterior prefrontal cortex or the hippocampus during false memories.

  12. Prolonged rote learning produces delayed memory facilitation and metabolic changes in the hippocampus of the ageing human brain

    Directory of Open Access Journals (Sweden)

    Prendergast Julie

    2009-11-01

    Full Text Available Abstract Background Repeated rehearsal is one method by which verbal material may be transferred from short- to long-term memory. We hypothesised that extended engagement of memory structures through prolonged rehearsal would result in enhanced efficacy of recall and also of brain structures implicated in new learning. Twenty-four normal participants aged 55-70 (mean = 60.1 engaged in six weeks of rote learning, during which they learned 500 words per week every week (prose, poetry etc.. An extensive battery of memory tests was administered on three occasions, each six weeks apart. In addition, proton magnetic resonance spectroscopy (1H-MRS was used to measure metabolite levels in seven voxels of interest (VOIs (including hippocampus before and after learning. Results Results indicate a facilitation of new learning that was evident six weeks after rote learning ceased. This facilitation occurred for verbal/episodic material only, and was mirrored by a metabolic change in left posterior hippocampus, specifically an increase in NAA/(Cr+Cho ratio. Conclusion Results suggest that repeated activation of memory structures facilitates anamnesis and may promote neuronal plasticity in the ageing brain, and that compliance is a key factor in such facilitation as the effect was confined to those who engaged fully with the training.

  13. Prolonged rote learning produces delayed memory facilitation and metabolic changes in the hippocampus of the ageing human brain.

    LENUS (Irish Health Repository)

    Roche, Richard Ap

    2009-01-01

    BACKGROUND: Repeated rehearsal is one method by which verbal material may be transferred from short- to long-term memory. We hypothesised that extended engagement of memory structures through prolonged rehearsal would result in enhanced efficacy of recall and also of brain structures implicated in new learning. Twenty-four normal participants aged 55-70 (mean = 60.1) engaged in six weeks of rote learning, during which they learned 500 words per week every week (prose, poetry etc.). An extensive battery of memory tests was administered on three occasions, each six weeks apart. In addition, proton magnetic resonance spectroscopy (1H-MRS) was used to measure metabolite levels in seven voxels of interest (VOIs) (including hippocampus) before and after learning. RESULTS: Results indicate a facilitation of new learning that was evident six weeks after rote learning ceased. This facilitation occurred for verbal\\/episodic material only, and was mirrored by a metabolic change in left posterior hippocampus, specifically an increase in NAA\\/(Cr+Cho) ratio. CONCLUSION: Results suggest that repeated activation of memory structures facilitates anamnesis and may promote neuronal plasticity in the ageing brain, and that compliance is a key factor in such facilitation as the effect was confined to those who engaged fully with the training.

  14. Executive Semantic Processing Is Underpinned by a Large-scale Neural Network: Revealing the Contribution of Left Prefrontal, Posterior Temporal, and Parietal Cortex to Controlled Retrieval and Selection Using TMS

    Science.gov (United States)

    Whitney, Carin; Kirk, Marie; O'Sullivan, Jamie; Ralph, Matthew A. Lambon; Jefferies, Elizabeth

    2012-01-01

    To understand the meanings of words and objects, we need to have knowledge about these items themselves plus executive mechanisms that compute and manipulate semantic information in a task-appropriate way. The neural basis for semantic control remains controversial. Neuroimaging studies have focused on the role of the left inferior frontal gyrus…

  15. Atrophy of the Posterior Subiculum Is Associated with Memory Impairment, Tau- and Aβ Pathology in Non-demented Individuals

    Directory of Open Access Journals (Sweden)

    Olof Lindberg

    2017-09-01

    Full Text Available Alzheimer’s disease (AD is associated with atrophy of the cornu ammonis (CA 1 and the subiculum subfield of the hippocampus (HC, and with deficits in episodic memory and spatial orientation. These deficits are mainly associated with the functionality of the posterior HC. We therefore hypothesized that key AD pathologies, i.e., β-amyloid and tau pathology would be particularly associated with the volume of the posterior subiculum in non-demented individuals. In our study we included 302 cognitively normal elderly participants (CN, 183 patients with subjective cognitive decline (SCD and 171 patients with amnestic mild cognitive impairment (MCI, all of whom underwent 3T magnetic resonance images (MRI. The subicular subfield was segmented using Freesurfer 5.3 and divided into 10 volumetric segments moving from the most posterior (segment 1 to the most anterior part along the axis of the hippocampal head and body (segment 10. Cerebrospinal fluid (CSF Aβ42 and phosphorylated tau (P-tau were quantified using ELISA and were used as biomarkers for β-amyloid and tau pathology, respectively. In the total sample, tau-pathology and Aβ-pathology and (measured by elevated P-tau and low Aβ42 levels in CSF and mild memory dysfunction were mostly associated with the volume changes of the posterior subiculum. Both SCD and MCI patients with elevated P-tau or low Aβ42 levels displayed predominantly posterior subicular atrophy in comparisons to control subjects with normal CSF biomarker levels. Finally, there was no main effect of Aβ42 or P-tau when comparing SCD with abnormal P-tau or Aβ42 with SCD with normal levels of these CSF-biomarkers. However, in the left subiculum there was a significant interaction revealing atrophy in the left posterior but not the anterior subiculum in participants with low Aβ42 levels. The same pattern was observed on the contralateral side in participants with elevated P-tau levels. In conclusion, AD pathologies and mild

  16. The hippocampus and visual perception

    Science.gov (United States)

    Lee, Andy C. H.; Yeung, Lok-Kin; Barense, Morgan D.

    2012-01-01

    In this review, we will discuss the idea that the hippocampus may be involved in both memory and perception, contrary to theories that posit functional and neuroanatomical segregation of these processes. This suggestion is based on a number of recent neuropsychological and functional neuroimaging studies that have demonstrated that the hippocampus is involved in the visual discrimination of complex spatial scene stimuli. We argue that these findings cannot be explained by long-term memory or working memory processing or, in the case of patient findings, dysfunction beyond the medial temporal lobe (MTL). Instead, these studies point toward a role for the hippocampus in higher-order spatial perception. We suggest that the hippocampus processes complex conjunctions of spatial features, and that it may be more appropriate to consider the representations for which this structure is critical, rather than the cognitive processes that it mediates. PMID:22529794

  17. The hippocampus and visual perception

    Directory of Open Access Journals (Sweden)

    Andy C. H. Lee

    2012-04-01

    Full Text Available In this review, we will discuss the idea that the hippocampus may be involved in both memory and perception, contrary to theories that posit functional and neuroanatomical segregation of these processes. This suggestion is based on a number of recent neuropsychological and functional neuroimaging studies that have demonstrated that the hippocampus is involved in the visual discrimination of complex spatial scene stimuli. We argue that these findings cannot be explained by long-term memory or working memory processing or, in the case of patient findings, dysfunction beyond the medial temporal lobe. Instead, these studies point towards a role for the hippocampus in higher-order spatial perception. We suggest that the hippocampus processes complex conjunctions of spatial features, and that it may be more appropriate to consider the representations for which this structure is critical, rather than the cognitive processes that it mediates.

  18. Visual attention in posterior stroke

    DEFF Research Database (Denmark)

    Fabricius, Charlotte; Petersen, Anders; Iversen, Helle K

    Objective: Impaired visual attention is common following strokes in the territory of the middle cerebral artery, particularly in the right hemisphere. However, attentional effects of more posterior lesions are less clear. The aim of this study was to characterize visual processing speed...... and apprehension span following posterior cerebral artery (PCA) stroke. We also relate these attentional parameters to visual word recognition, as previous studies have suggested that reduced visual speed and span may explain pure alexia. Methods: Nine patients with MR-verified focal lesions in the PCA......-territory (four left PCA; four right PCA; one bilateral, all >1 year post stroke) were compared to 25 controls using single case statistics. Visual attention was characterized by a whole report paradigm allowing for hemifield-specific speed and span measurements. We also characterized visual field defects...

  19. Posterior Cruciate Ligament Injury

    Science.gov (United States)

    ... the thighbone (femur) to the shinbone (tibia). The anterior and posterior cruciate ligaments form an "X" in the center of the knee. Although a posterior cruciate ligament injury generally causes less pain, disability and knee instability than does an ACL ...

  20. Hippocampal and posterior parietal contributions to developmental increases in visual short-term memory capacity.

    Science.gov (United States)

    von Allmen, David Yoh; Wurmitzer, Karoline; Klaver, Peter

    2014-10-01

    Developmental increases in visual short-term memory (VSTM) capacity have been associated with changes in attention processing limitations and changes in neural activity within neural networks including the posterior parietal cortex (PPC). A growing body of evidence suggests that the hippocampus plays a role in VSTM, but it is unknown whether the hippocampus contributes to the capacity increase across development. We investigated the functional development of the hippocampus and PPC in 57 children, adolescents and adults (age 8-27 years) who performed a visuo-spatial change detection task. A negative relationship between age and VSTM related activity was found in the right posterior hippocampus that was paralleled by a positive age-activity relationship in the right PPC. In the posterior hippocampus, VSTM related activity predicted individual capacity in children, whereas neural activity in the right anterior hippocampus predicted individual capacity in adults. The findings provide first evidence that VSTM development is supported by an integrated neural network that involves hippocampal and posterior parietal regions.

  1. Functional connectivity of the hippocampus in temporal lobe epilepsy: feasibility of a task-regressed seed-based approach.

    Science.gov (United States)

    Kucukboyaci, Nuri Erkut; Kemmotsu, Nobuko; Cheng, Chris E; Girard, Holly M; Tecoma, Evelyn S; Iragui, Vicente J; McDonald, Carrie R

    2013-01-01

    Resting-state functional connectivity (FC) has revealed marked network dysfunction in patients with temporal lobe epilepsy (TLE) compared to healthy controls. However, the nature and the location of these changes have not been fully elucidated nor confirmed by other methodologies. We assessed the presence of hippocampal FC changes in TLE based on the low frequency residuals of task-related functional magnetic resonance imaging data after the removal of task-related activation [i.e., task-regressed functional connectivity MRI (fcMRI)]. We employed a novel, task-regressed approach to quantify hippocampal FC, and compare hippocampal FC in 17 patients with unilateral TLE (9 left) with 17 healthy controls. Our results suggest widespread FC reductions in the mesial cortex associated with the default mode network (DMN), and some local FC increases in the lateral portions of the right hemisphere. We found more pronounced FC decreases in the left hemisphere than in the right, and these FC decreases were greatest in patients with left TLE. Moreover, the FC reductions observed between the hippocampus and posterior cingulate, inferior parietal, paracentral regions are in agreement with previous resting state studies. Consistent with the existing literature, FC reductions in TLE appear widespread with prominent reductions in the medial portion of the DMN. Our data expand the literature by demonstrating that reductions in FC may be greatest in the left hemisphere and in patients with left TLE. Overall, our findings suggest that task-regressed FC is a viable alternative to resting state and that future studies may extract similar information on network connectivity from already existing datasets.

  2. Posterior reversible leukoencephalopathy syndrome after kratom ingestion.

    Science.gov (United States)

    Castillo, Austin; Payne, J Drew; Nugent, Kenneth

    2017-07-01

    Posterior reversible encephalopathy syndrome has been associated with hypertension, preeclampsia, cancer chemotherapy, and drugs of abuse, such as amphetamine and methamphetamine. We report a young man who suddenly developed severe headache, disorientation, and aphasia following ingestion of kratom and Adderall. Computed tomography and magnetic resonance imaging of his head revealed foci of vasogenic edema in the posterior occipital lobes, frontal lobes, and brainstem. In addition, he had a small area of hemorrhage in the left posterior occipital lobe. Lumbar puncture revealed an increased number of red blood cells but no other abnormalities. His initial blood pressure was elevated but returned to normal during hospitalization. This case suggests that kratom can cause posterior reversible encephalopathy syndrome and needs to be considered when patients present to emergency centers with headaches, confusion, and visual disturbances.

  3. Recurrent Massive Epistaxis from an Anomalous Posterior Ethmoid Artery

    OpenAIRE

    Greco, Marco Giuseppe; Mattioli, Francesco; Alberici, Maria Paola; Presutti, Livio

    2016-01-01

    A 50-year-old man, with no previous history of epistaxis, was hospitalized at our facility for left recurrent posterior epistaxis. The patient underwent surgical treatment three times and only the operator’s experience and radiological support (cranial angiography) allowed us to control the epistaxis and stop the bleeding. The difficult bleeding management and control was attributed to an abnormal course of the left posterior ethmoidal artery. When bleeding seems to come from the roof of the ...

  4. Echocardiographic Wall Motion Abnormality in Posterior Myocardial Infarction: The Diagnostic Value of Posterior Leads

    Directory of Open Access Journals (Sweden)

    A Darehzereshki

    2008-06-01

    Full Text Available Background: For the purpose of ascertaining myocardial infarction (MI and ischemia, the sensitivity of the initial 12-lead ECG is inadequate. It is risky to diagnose posterior MI using only precordial reciprocal changes, since the other leads may be more optimally positioned for the identification of electrocardiographic changes. In this study, we evaluated the relationship between electrocardiography changes and wall motion abnormalities in patients with posterior MI for earlier and better diagnosis of posterior MI.Methods: In this prospective cross-sectional study, we enrolled patients with posterior MI who had come to the Emergency Department of Shariati Hospital with their first episode of chest pain. A 12-lead surface electrocardiogram using posterior leads (V7-V9 was performed for all participants. Patients with ST elevation >0.05 mV or pathologic Q wave in the posterior leads, as well as those with specific changes indicating posterior MI in V1-V2, were evaluated by echocardiography in terms of wall motion abnormalities. All data were analyzed using SPSS and p<0.05 were considered statistically significant.Results: Of a total 79 patients enrolled, 48 (60.8% were men, and the mean age was 57.35±8.22 years. Smoking (54.4% and diabetes (48% were the most prevalent risk factors. In the echocardiographic evaluation, all patients had wall motion abnormalities in the left ventricle and 19 patients (24.1% had wall motion abnormalities in the right ventricle. The most frequent segment with motion abnormality among the all patients was the mid-posterior. The posterior leads showed better positive predictive value than the anterior leads for posterior wall motion abnormality.Conclusion: Electrocardiography of the posterior leads in patients with acute chest pain can help in earlier diagnosis and in time treatment of posterior MI.

  5. Nanotherapy for posterior eye diseases.

    Science.gov (United States)

    Kaur, Indu Pal; Kakkar, Shilpa

    2014-11-10

    It is assumed that more than 50% of the most enfeebling ocular diseases have their origin in the posterior segment. Furthermore, most of these diseases lead to partial or complete blindness, if left untreated. After cancer, blindness is the second most dreaded disease world over. However, treatment of posterior eye diseases is more challenging than the anterior segment ailments due to a series of anatomical barriers and physiological constraints confronted for delivery to this segment. In this regard, nanostructured drug delivery systems are proposed to defy ocular barriers, target retina, and act as permeation enhancers in addition to providing a controlled release. Since an important step towards developing effective treatment strategies is to understand the course or a route a drug molecule needs to follow to reach the target site, the first part of the present review discusses various pathways available for effective delivery to and clearance from the posterior eye. Promise held by nanocarrier systems, viz. liposomes, nanoparticles, and nanoemulsion, for effective delivery and selective targeting is also discussed with illustrative examples, tables, and flowcharts. However, the applicability of these nanocarrier systems as self-administration ocular drops is still an unrealized dream which is in itself a huge technological challenge. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Hippocampus-dependent place learning enables spatial flexibility in mice

    Directory of Open Access Journals (Sweden)

    Karl R. Kleinknecht

    2012-12-01

    Full Text Available Spatial navigation is a fundamental capability necessary in everyday life to locate food, social partners and shelter. It results from two very different strategies: (i place learning which enables for flexible way finding and (ii response learning that leads to a more rigid ‘route following’. Despite the importance of knockout techniques that are only available in mice, little is known about mice’ flexibility in spatial navigation tasks.Here we demonstrate for C57BL6/N mice in a water-cross maze that only place learning enables spatial flexibility and relearning of a platform position, whereas response learning does not. This capability depends on an intact hippocampal formation, since hippocampus lesions by ibotenic acid disrupted relearning. In vivo manganese-enhanced magnetic resonance imaging revealed a volume loss of ≥ 60% of the hippocampus as a critical threshold for relearning impairments. In particular the changes in the left ventral hippocampus were indicative of relearning deficits.In summary, our findings establish the importance of hippocampus-dependent place learning for spatial flexibility and provide a first systematic analysis on spatial flexibility in mice.

  7. Incomplete inversion of the hippocampus - a common developmental anomaly

    Energy Technology Data Exchange (ETDEWEB)

    Bajic, Dragan; Wang, Chen; Raininko, Raili [Uppsala University Hospital, Department of Radiology, Uppsala (Sweden); Kumlien, Eva; Mattsson, Peter [Uppsala University Hospital, Department of Neurology, Uppsala (Sweden); Lundberg, Staffan; Eeg-Olofsson, Orvar [Uppsala University Hospital, Department of Child Neurology, Uppsala (Sweden)

    2008-01-15

    Incomplete inversion of the hippocampus, an imperfect fetal development, has been described in patients with epilepsy or severe midline malformations. We studied this condition in a nonepileptic population without obvious developmental anomalies. We analyzed the coronal MR images of 50 women and 50 men who did not have epilepsy. Twenty of them were healthy volunteers and 80 were patients without obvious intracranial developmental anomalies, intracranial masses, hydrocephalus or any condition affecting the temporal lobes. If the entire hippocampus (the head could not be evaluated) were affected, the incomplete inversion was classified as total, otherwise as partial. Incomplete inversion of the hippocampus was found in 19/100 subjects (9 women, 10 men). It was unilateral, always on the left side, in 13 subjects (4 women, 9 men): 9 were of the total type, 4 were partial. It was bilateral in six subjects (five women, one man): four subjects had total types bilaterally, two had a combination of total and partial types. The collateral sulcus was vertically oriented in all subjects with a deviating hippocampal shape. We conclude that incomplete inversion of the hippocampus is not an unusual morphologic variety in a nonepileptic population without other obvious intracranial developmental anomalies. (orig.)

  8. Posterior labrocapsular periosteal sleeve avulsion complicating locked posterior shoulder dislocation

    Energy Technology Data Exchange (ETDEWEB)

    Simons, P. [Department of Radiology, Onze Lieve Vrouwe Hospital, Aalst (Belgium)]|[Department of Radiology, Leiden University Medical Centre, Leiden (Netherlands); Joekes, E.; Bloem, J.L. [Department of Radiology, Leiden University Medical Centre, Leiden (Netherlands); Nelissen, R.G.H.H. [Department of Orthopaedic Surgery, Leiden University Medical Centre (Netherlands)

    1998-10-01

    This case presents the imaging features of a posterior shoulder dislocation complicated by a rare but surgically relevant lesion of the posterior labrum. Due to the attachment of the posterior capsule to the posterior portion of the labrum, which in itself is attached to the posterior scapular periosteum, stripping of the labrum by the posterior capsule resulted in a posterior labrocapsular periosteal sleeve avulsion. (orig.) With 4 figs., 5 refs.

  9. Malignant ectomesenchymoma of the posterior mediastinum

    International Nuclear Information System (INIS)

    Khan, M. H.; Iqbal, R.; Hafeez-UR-Rehman; Yaqub, N.; Anwar-ul-Haq

    2001-01-01

    The surgical management of a four years old female child, presented at the Islamic International Medical Complex (IIMC), Islamabad, with three months history of recurrent chest infections and failure to thrive, is discussed. Posterior mediastinal tumor was diagnosed radiologically. Tumor had flimsy attachments with pericardium and thoracic aorta but was densely adherent with lower lobe of left lung. The tumor was completely removed along with a segment of lung. The postoperative recovery was uneventful. The diagnosis of malignant ectomesenchymoma was made on histopathology. The patients is well in follow-up. This is the first reported case of malignant ectomesenchymoma arising within posterior mediastinum. (author)

  10. Resistance exercise improves hippocampus-dependent memory

    Directory of Open Access Journals (Sweden)

    R.C. Cassilhas

    2012-12-01

    Full Text Available It has been demonstrated that resistance exercise improves cognitive functions in humans. Thus, an animal model that mimics this phenomenon can be an important tool for studying the underlying neurophysiological mechanisms. Here, we tested if an animal model for resistance exercise was able to improve the performance in a hippocampus-dependent memory task. In addition, we also evaluated the level of insulin-like growth factor 1/insulin growth factor receptor (IGF-1/IGF-1R, which plays pleiotropic roles in the nervous system. Adult male Wistar rats were divided into three groups (N = 10 for each group: control, SHAM, and resistance exercise (RES. The RES group was submitted to 8 weeks of progressive resistance exercise in a vertical ladder apparatus, while the SHAM group was left in the same apparatus without exercising. Analysis of a cross-sectional area of the flexor digitorum longus muscle indicated that this training period was sufficient to cause muscle fiber hypertrophy. In a step-through passive avoidance task (PA, the RES group presented a longer latency than the other groups on the test day. We also observed an increase of 43 and 94% for systemic and hippocampal IGF-1 concentration, respectively, in the RES group compared to the others. A positive correlation was established between PA performance and systemic IGF-1 (r = 0.46, P < 0.05. Taken together, our data indicate that resistance exercise improves the hippocampus-dependent memory task with a concomitant increase of IGF-1 level in the rat model. This model can be further explored to better understand the effects of resistance exercise on brain functions.

  11. Posterior fossa epidural hematoma

    International Nuclear Information System (INIS)

    Kushner, M.J.; Luken, M.G. III

    1983-01-01

    CT demonstrated posterior fossa epidural hematoma in three patients with head trauma in whom this diagnosis was not clinically apparent. No patient was in stupor or coma and no patient experienced a lucid interval. Only one patient had signs referable to the posterior fossa. Two patients had occipital skull fracture disclosed by plain radiographs. CT revealed a unilateral biconvex hematoma in two cases, and a bilateral hematoma with supratentorial extension in the third. All patients underwent suboccipital craniectomy and recovered. Therapeutic success in these cases was facilitated by early CT and the rapid disclosure of the unsuspected posterior fossa lesions. CT showing contiguous hematoma below and above the tentorium cerebelli after posterior head trauma is highly suggestive of epidural hematoma arising from the posterior fossa. (orig.)

  12. Posterior Communicating Artery Aneurysm in a 20 Year Old Boy ...

    African Journals Online (AJOL)

    Result: A clinical diagnosis of left third and fourth cranial nerve palsies from intracranial space-occupying lesion was made. Computed tomography and computed tomography angiography confirmed left posterior communicating artery aneurysm. Conclusion: Any degree of pupillary involvement in third nerve palsy, whether ...

  13. Cervical subluxation associated with posterior cervical hemivertebra.

    Science.gov (United States)

    Otero-López, R; Rivero-Garvía, M; Márquez-Rivas, J; Valencia, J

    2016-02-01

    Hemivertebrae, associated with a failure in the formation and fusion of vertebral body ossification nuclei, are a common cause of thoracic or lumbar scoliosis. A cervical location is rare and even rarer as a cause of cervical subluxation in flexion and extension (for which only one previous case has been found). We report on the case of a 7-year-old female patient, who was examined for a cervical fusion defect, consisting of a posterior C4 hemivertebra and a left hemiblock from C5 to C7. After performing surgery consisting of a C4 corpectomy and anterior fixation with intersomatic graft and plate, adequate cervical stabilization with only a self-limiting left C6 brachialgia and ipsilateral Horner syndrome occurs in the postoperative period. Posterior cervical hemivertebra associated with instability is a very rare finding. The anterior approach with corpectomy and anterior plate enables suitable stabilization.

  14. Decrease of extracellular taurine in the rat dorsal hippocampus after central nervous administration of vasopressin

    DEFF Research Database (Denmark)

    Brust, P; Christensen, Thomas; Diemer, Nils Henrik

    1992-01-01

    of the composition of the extracellular fluid. The concentrations of 16 amino acids were measured by HPLC in the perfusate samples. The level of taurine declined 20% in the right hippocampus during perfusion with vasopressin, whereas o-phosphoethanolamine decreased in both sides, the left 20% and the right 24...

  15. Aphasia following left thalamic hemorrhage

    International Nuclear Information System (INIS)

    Makishita, Hideo; Miyasaka, Motomaro; Tanizaki, Yoshio; Yanagisawa, Nobuo; Sugishita, Morihiro.

    1984-01-01

    We reported 7 patients with left thalamic hemorrhage in the chronic stage (from 1.5 months to 4.5 months), and described language disorders examined by Western Aphasia Battery (WAB) and measured cerebral blood flow by single photon emission CT. Examination of language by WAB revealed 4 aphasics out of 7 cases, and 3 patients had no language deficit. The patient with Wernicke's aphasia showed low density area only in the left posterior thalamus in X-ray CT, and revealed severe low blood flow area extending to left temporal lobe in emission CT. In the case with transcortical sensory aphasia, although X-ray CT showed no obvious low density area, emission CT revealed moderate low flow area in watershed area that involved the territory between posterior cerebral and middle cerebral arteries in the left temporooccipital region in addition to low blood flow at the left thalamus. In one of the two patients classified as anomic aphasia, whose score of repetition (8.4) was higher than that of comprehension (7.4), emission CT showed slight low flow area at the temporo-occipital region similarly as the case with transcortical sensory aphasia. In another case with anomic aphasia, scored 9 on both fluensy and comprehension subtests and 10 on repetition, there was wide low density area all over the left thalamus and midline shift to the right in X-ray CT, and emission CT showed severe low blood flow in the same region spreading widely toward the cerebral surface. On the other hand, in all of the 3 patients without aphasia, emission CT showed low flow region restricted to the left thalamus. (J.P.N.)

  16. The posterior parahippocampal gyrus is preferentially affected in age-related memory decline.

    NARCIS (Netherlands)

    Burgmans, S.; van Boxtel, M.P.J.; van den Berg, K.E.M.; Gronenschild, E.H.B.M.; Jacobs, H.I.L.; Jolles, J.; Uylings, H.B.M.

    2011-01-01

    Atrophy in the medial temporal lobe is generally considered to be highly associated with age-related memory decline. Volume loss in the hippocampus and entorhinal cortex has extensively been investigated, but the posterior parts of the parahippocampal gyrus have received little attention. The

  17. The posterior parahippocampal gyrus is preferentially affected in age-related memory decline

    NARCIS (Netherlands)

    Burgmans, S.; van Boxtel, M.P.J.; van den Berg, K.E.M.; Gronenschild, E.H.; Jacobs, H.I.L.; Jolles, J.; Uylings, H.B.M.

    2009-01-01

    Atrophy in the medial temporal lobe is generally considered to be highly associated with age-related memory decline. Volume loss in the hippocampus and entorhinal cortex has extensively been investigated, but the posterior parts of the parahippocampal gyrus have received little attention. The

  18. Spondylolisthesis and Posterior Instability

    International Nuclear Information System (INIS)

    Niggemann, P.; Beyer, H.K.; Frey, H.; Grosskurth, D.; Simons, P.; Kuchta, J.

    2009-01-01

    We present the case of a patient with a spondylolisthesis of L5 on S1 due to spondylolysis at the level L5/S1. The vertebral slip was fixed and no anterior instability was found. Using functional magnetic resonance imaging (MRI) in an upright MRI scanner, posterior instability at the level of the spondylolytic defect of L5 was demonstrated. A structure, probably the hypertrophic ligament flava, arising from the spondylolytic defect was displaced toward the L5 nerve root, and a bilateral contact of the displaced structure with the L5 nerve root was shown in extension of the spine. To our knowledge, this is the first case described of posterior instability in patients with spondylolisthesis. The clinical implications of posterior instability are unknown; however, it is thought that this disorder is common and that it can only be diagnosed using upright MRI

  19. Spondylolisthesis and Posterior Instability

    Energy Technology Data Exchange (ETDEWEB)

    Niggemann, P.; Beyer, H.K.; Frey, H.; Grosskurth, D. (Privatpraxis fuer Upright MRT, Koeln (Germany)); Simons, P.; Kuchta, J. (Media Park Klinik, Koeln (Germany))

    2009-04-15

    We present the case of a patient with a spondylolisthesis of L5 on S1 due to spondylolysis at the level L5/S1. The vertebral slip was fixed and no anterior instability was found. Using functional magnetic resonance imaging (MRI) in an upright MRI scanner, posterior instability at the level of the spondylolytic defect of L5 was demonstrated. A structure, probably the hypertrophic ligament flava, arising from the spondylolytic defect was displaced toward the L5 nerve root, and a bilateral contact of the displaced structure with the L5 nerve root was shown in extension of the spine. To our knowledge, this is the first case described of posterior instability in patients with spondylolisthesis. The clinical implications of posterior instability are unknown; however, it is thought that this disorder is common and that it can only be diagnosed using upright MRI.

  20. Stress, memory, and the hippocampus.

    Science.gov (United States)

    Wingenfeld, Katja; Wolf, Oliver T

    2014-01-01

    Stress hormones, i.e. cortisol in human and cortisone in rodents, influence a wide range of cognitive functions, including hippocampus-based declarative memory performance. Cortisol enhances memory consolidation, but impairs memory retrieval. In this context glucocorticoid receptor sensitivity and hippocampal integrity play an important role. This review integrates findings on the relationships between the hypothalamus-pituitary-adrenal (HPA) axis, one of the main coordinators of the stress response, hippocampus, and memory. Findings obtained in healthy participants will be compared with selected mental disorders, including major depressive disorder (MDD), posttraumatic stress disorder (PTSD), and borderline personality disorder (BPD). These disorders are characterized by alterations of the HPA axis and hippocampal dysfunctions. Interestingly, the acute effects of stress hormones on memory in psychiatric patients are different from those found in healthy humans. While cortisol administration has failed to affect memory retrieval in patients with MDD, patients with PTSD and BPD have been found to show enhanced rather than impaired memory retrieval after hydrocortisone. This indicates an altered sensitivity to stress hormones in these mental disorders. © 2014 S. Karger AG, Basel

  1. Does the hippocampus mediate objective binding or subjective remembering?

    Science.gov (United States)

    Slotnick, Scott D

    2010-01-15

    Human functional magnetic resonance imaging (fMRI) evidence suggests the hippocampus is associated with context memory to a greater degree than item memory (where only context memory requires item-in-context binding). A separate line of fMRI research suggests the hippocampus is associated with "remember" responses to a greater degree than "know" or familiarity based responses (where only remembering reflects the subjective experience of specific detail). Previous studies, however, have confounded context memory with remembering and item memory with knowing. The present fMRI study independently tested the binding hypothesis and remembering hypothesis of hippocampal function by evaluating activity within hippocampal regions-of-interest (ROIs). At encoding, participants were presented with colored and gray abstract shapes and instructed to remember each shape and whether it was colored or gray. At retrieval, old and new shapes were presented in gray and participants classified each shape as "old and previously colored", "old and previously gray", or "new", followed by a "remember" or "know" response. In 3 of 11 hippocampal ROIs, activity was significantly greater for context memory than item memory, the context memory-item memory by remember-know interaction was significant, and activity was significantly greater for context memory-knowing than item memory-remembering. This pattern of activity only supports the binding hypothesis. The analogous pattern of activity that would have supported the remembering hypothesis was never observed in the hippocampus. However, a targeted analysis revealed remembering specific activity in the left inferior parietal cortex. The present results suggest parietal cortex may be associated with subjective remembering while the hippocampus mediates binding.

  2. Posterior tracheal diverticulosis.

    Science.gov (United States)

    Madan, Karan; Das, Chandan J; Guleria, Randeep

    2014-10-01

    Multiple tracheal diverticulosis is a rare clinical entity. Tracheal diverticula are usually recognized radiologically as solitary right paratracheal air collections on thoracic computed tomography examination. They are usually asymptomatic but can occasionally present with persistent symptoms. We herein report the case of a 50-year-old male patient who underwent extensive evaluation for persistent cough. Multiple posterior right paratracheal air collections were recognized on thoracic multidetector computed tomography examination, which was confirmed as multiple-acquired posterior upper tracheal diverticula on flexible bronchoscopy. The patient improved with conservative medical management.

  3. Involvement of posterior cingulate cortex in ketamine-induced psychosis relevant behaviors in rats.

    Science.gov (United States)

    Ma, Jingyi; Leung, L Stan

    2018-02-15

    The involvement of posterior cingulate cortex (PCC) on ketamine-induced psychosis relevant behaviors was investigated in rats. Bilateral infusion of muscimol, a GABA A receptor agonist, into the PCC significantly antagonized ketamine-induced deficit in prepulse inhibition of a startle reflex (PPI), deficit in gating of hippocampal auditory evoked potentials, and behavioral hyperlocomotion in a dose dependent manner. Local infusion of ketamine directly into the PCC also induced a PPI deficit. Systemic injection of ketamine (3mg/kg,s.c.) induced an increase in power of electrographic activity in the gamma band (30-100Hz) in both the PCC and the hippocampus; peak theta (4-10Hz) power was not significantly altered, but peak theta frequency was increased by ketamine. In order to exclude volume conduction from the hippocampus to PCC, inactivation of the hippocampus was made by local infusion of muscimol into the hippocampus prior to ketamine administration. Muscimol in the hippocampus effectively blocked ketamine-induced increase of gamma power in the hippocampus but not in the PCC, suggesting independent generation of gamma waves in PCC and hippocampus. It is suggested that the PCC is part of the brain network mediating ketamine-induced psychosis related behaviors. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Seasonal change in the avian hippocampus.

    Science.gov (United States)

    Sherry, David F; MacDougall-Shackleton, Scott A

    2015-04-01

    The hippocampus plays an important role in cognitive processes, including memory and spatial orientation, in birds. The hippocampus undergoes seasonal change in food-storing birds and brood parasites, there are changes in the hippocampus during breeding, and further changes occur in some species in association with migration. In food-storing birds, seasonal change in the hippocampus occurs in fall and winter when the cognitively demanding behaviour of caching and retrieving food occurs. The timing of annual change in the hippocampus of food-storing birds is quite variable, however, and appears not to be under photoperiod control. A variety of factors, including cognitive performance, exercise, and stress may all influence seasonal change in the avian hippocampus. The causal processes underlying seasonal change in the avian hippocampus have not been extensively examined and the more fully described hormonal influences on the mammalian hippocampus may provide hypotheses for investigating the control of hippocampal seasonality in birds. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Posterior Urethral Valves

    Directory of Open Access Journals (Sweden)

    Steve J. Hodges

    2009-01-01

    Full Text Available The most common cause of lower urinary tract obstruction in male infants is posterior urethral valves. Although the incidence has remained stable, the neonatal mortality for this disorder has improved due to early diagnosis and intensive neonatal care, thanks in part to the widespread use of prenatal ultrasound evaluations. In fact, the most common reason for the diagnosis of posterior urethral valves presently is the evaluation of infants for prenatal hydronephrosis. Since these children are often diagnosed early, the urethral obstruction can be alleviated rapidly through catheter insertion and eventual surgery, and their metabolic derangements can be normalized without delay, avoiding preventable infant mortality. Of the children that survive, however, early diagnosis has not had much effect on their long-term prognosis, as 30% still develop renal insufficiency before adolescence. A better understanding of the exact cause of the congenital obstruction of the male posterior urethra, prevention of postnatal bladder and renal injury, and the development of safe methods to treat urethral obstruction prenatally (and thereby avoiding the bladder and renal damage due to obstructive uropathy are the goals for the care of children with posterior urethral valves[1].

  6. Visualisation of the left superior intercostal vein in MR

    International Nuclear Information System (INIS)

    Medrea, M.; Meydam, K.; Schmitt, W.

    1987-01-01

    A retrospective study of 56 MRT chest examinations showed the left intercostal vein in its horizontal trajectory in 3 patients with left mediastinal masses compressing the superior vena cava. In 2 patients the posterior trajectory of the horizontal segment was clearly visualised. In the third case the anterior part, namely the insertion of the left superior intercostal vein into the left brachiocephalic trunk, was demonstrated. (orig.) [de

  7. Mnemonic convergence in the human hippocampus.

    Science.gov (United States)

    Backus, Alexander R; Bosch, Sander E; Ekman, Matthias; Grabovetsky, Alejandro Vicente; Doeller, Christian F

    2016-06-21

    The ability to form associations between a multitude of events is the hallmark of episodic memory. Computational models have espoused the importance of the hippocampus as convergence zone, binding different aspects of an episode into a coherent representation, by integrating information from multiple brain regions. However, evidence for this long-held hypothesis is limited, since previous work has largely focused on representational and network properties of the hippocampus in isolation. Here we identify the hippocampus as mnemonic convergence zone, using a combination of multivariate pattern and graph-theoretical network analyses of functional magnetic resonance imaging data from humans performing an associative memory task. We observe overlap of conjunctive coding and hub-like network attributes in the hippocampus. These results provide evidence for mnemonic convergence in the hippocampus, underlying the integration of distributed information into episodic memory representations.

  8. Navigating the auditory scene: an expert role for the hippocampus.

    Science.gov (United States)

    Teki, Sundeep; Kumar, Sukhbinder; von Kriegstein, Katharina; Stewart, Lauren; Lyness, C Rebecca; Moore, Brian C J; Capleton, Brian; Griffiths, Timothy D

    2012-08-29

    Over a typical career piano tuners spend tens of thousands of hours exploring a specialized acoustic environment. Tuning requires accurate perception and adjustment of beats in two-note chords that serve as a navigational device to move between points in previously learned acoustic scenes. It is a two-stage process that depends on the following: first, selective listening to beats within frequency windows, and, second, the subsequent use of those beats to navigate through a complex soundscape. The neuroanatomical substrates underlying brain specialization for such fundamental organization of sound scenes are unknown. Here, we demonstrate that professional piano tuners are significantly better than controls matched for age and musical ability on a psychophysical task simulating active listening to beats within frequency windows that is based on amplitude modulation rate discrimination. Tuners show a categorical increase in gray matter volume in the right frontal operculum and right superior temporal lobe. Tuners also show a striking enhancement of gray matter volume in the anterior hippocampus, parahippocampal gyrus, and superior temporal gyrus, and an increase in white matter volume in the posterior hippocampus as a function of years of tuning experience. The relationship with gray matter volume is sensitive to years of tuning experience and starting age but not actual age or level of musicality. Our findings support a role for a core set of regions in the hippocampus and superior temporal cortex in skilled exploration of complex sound scenes in which precise sound "templates" are encoded and consolidated into memory over time in an experience-dependent manner.

  9. Navigating the auditory scene: an expert role for the hippocampus

    Science.gov (United States)

    Teki, Sundeep; Kumar, Sukhbinder; von Kriegstein, Katharina; Stewart, Lauren; Lyness, C. Rebecca; Moore, Brian C. J.; Capleton, Brian; Griffiths, Timothy D.

    2012-01-01

    Over a typical career piano tuners spend tens of thousands of hours exploring a specialized acoustic environment. Tuning requires accurate perception and adjustment of beats in two-note chords that serve as a navigational device to move between points in previously learned acoustic scenes. It is a two-stage process that depends on: firstly, selective listening to beats within frequency windows and, secondly, the subsequent use of those beats to navigate through a complex soundscape. The neuroanatomical substrates underlying brain specialization for such fundamental organization of sound scenes are unknown. Here, we demonstrate that professional piano tuners are significantly better than controls matched for age and musical ability on a psychophysical task simulating active listening to beats within frequency windows that is based on amplitude modulation rate discrimination. Tuners show a categorical increase in grey matter volume in the right frontal operculum and right superior temporal lobe. Tuners also show a striking enhancement of grey matter volume in the anterior hippocampus, parahippocampal gyrus, and superior temporal gyrus, and an increase in white matter volume in the posterior hippocampus as a function of years of tuning experience. The relationship with GM volume is sensitive to years of tuning experience and starting age but not actual age or level of musicality. Our findings support a role for a core set of regions in the hippocampus and superior temporal cortex in skilled exploration of complex sound scenes in which precise sound ‘templates’ are encoded and consolidated into memory over time in an experience-dependent manner. PMID:22933806

  10. Recurrent Massive Epistaxis from an Anomalous Posterior Ethmoid Artery.

    Science.gov (United States)

    Greco, Marco Giuseppe; Mattioli, Francesco; Alberici, Maria Paola; Presutti, Livio

    2016-01-01

    A 50-year-old man, with no previous history of epistaxis, was hospitalized at our facility for left recurrent posterior epistaxis. The patient underwent surgical treatment three times and only the operator's experience and radiological support (cranial angiography) allowed us to control the epistaxis and stop the bleeding. The difficult bleeding management and control was attributed to an abnormal course of the left posterior ethmoidal artery. When bleeding seems to come from the roof of the nasal cavity, it is important to identify the ethmoid arteries always bearing in mind the possible existence of anomalous courses.

  11. Recurrent Massive Epistaxis from an Anomalous Posterior Ethmoid Artery

    Directory of Open Access Journals (Sweden)

    Marco Giuseppe Greco

    2016-01-01

    Full Text Available A 50-year-old man, with no previous history of epistaxis, was hospitalized at our facility for left recurrent posterior epistaxis. The patient underwent surgical treatment three times and only the operator’s experience and radiological support (cranial angiography allowed us to control the epistaxis and stop the bleeding. The difficult bleeding management and control was attributed to an abnormal course of the left posterior ethmoidal artery. When bleeding seems to come from the roof of the nasal cavity, it is important to identify the ethmoid arteries always bearing in mind the possible existence of anomalous courses.

  12. Anatomic guidelines defined by reformatting images on MRI for volume measurement of amygdala and hippocampus

    International Nuclear Information System (INIS)

    Hoshida, Tohru; Sakaki, Toshisuke; Uematsu, Sumio.

    1995-01-01

    Twelve patients with intractable partial epilepsy underwent MR scans at the Epilepsy Center of the Johns Hopkins Hospital. There were five women and seven men, ranging in age from five to 51 years (mean age: 26 years). Coronal images were obtained using a 3-D SPGR. The coronal images were transferred to an Allegro 5.1 workstation, and reformatted along the cardinal axes (axial and sagittal) in multiple view points. The anterior end of the amygdala was measured at the level just posterior to the disappearance of the temporal stem. The semilunar gyrus of the amygdala was separated from the ambient gyrus by the semianular sulcus that forms the boundary between the amygdala and the entorhinal cortex. The delineation of the hippocampal formation included the subicular complex, hippocampal proper, dentate gyrus, alveus, and fimbria. The uncal cleft separated the uncus above from the parahippocampal gyrus below. The roof of this cleft was formed by the hippocampus and the dentate gyrus, and the floor, by the presubiculum and subiculum. Although using some guidelines, strictly separating the hippocampal head from the posterior part of the amygdala was not feasible as was previously reported, because of the isointensity on MRI between the cortex of the amygdala and the hippocampus. The most posterior portion of the hippocampus was measured at the level of the subsplenial gyri, just below the splenium of the corpus callosum, to measure the hippocampal volume in its near totality. Therefore, it is reliable, and clinically useful, to measure the combined total volume of the amygdala and the hippocampus when comparing results with those of other centers. (S.Y.)

  13. Posterior Reversible Encephalopathy (PRES)

    International Nuclear Information System (INIS)

    Moron E, Fanny E; Diaz Marchan, Pedro

    2005-01-01

    The Posterior Reversible Encephalopathy Syndrome (PRES) is a clinical Syndrome composed of cephalea, alteration in vision and convulsions, usually observed in patients with sudden elevation of arterial pressure. The imagenologic evidence shows reversible vasogenic brain edema without stroke. Its location is predominantly posterior; it affects the cortex and the subcortical white matter of the occipital, parietal and temporal lobes. The treatment with antihypertensive drugs and the removing of immunosupressor medication are generally associated with complete neurological recovery; this is reflected also in the images which return to their basal condition. The untreated hypertension, on the other side, can result in a progressive defect of the autoregulation system of the central nervous system with cerebral hemorrhage, irreversible brain stroke, coma and death

  14. The 5-HT(4) receptor levels in hippocampus correlates inversely with memory test performance in humans

    DEFF Research Database (Denmark)

    Haahr, Mette Ewers; Fisher, Patrick; Holst, Klaus Kähler

    2013-01-01

    in hippocampus. However, any associations between memory functions and the expression of the 5-HT(4) R in the human hippocampus have not been investigated. Using positron emission tomography with the tracer [(11) C]SB207145 and Reys Auditory Verbal Learning Test we aimed to examine the individual variation......The cerebral serotonin (5-HT) system is involved in cognitive functions such as memory and learning and animal studies have repeatedly shown that stimulation of the 5-HT type 4 receptor (5-HT(4) R) facilitates memory and learning and further that the 5-HT(4) R modulates cellular memory processes...... of the 5-HT4R binding in hippocampus in relation to memory acquisition and consolidation in healthy young volunteers. We found significant, negative associations between the immediate recall scores and left and right hippocampal BP(ND) , (p = 0.009 and p = 0.010 respectively) and between the right...

  15. ARE LEFT HANDED SURGEONS LEFT OUT?

    OpenAIRE

    SriKamkshi Kothandaraman; Balasubramanian Thiagarajan

    2012-01-01

    Being a left-handed surgeon, more specifically a left-handed ENT surgeon, presents a unique pattern of difficulties.This article is an overview of left-handedness and a personal account of the specific difficulties a left-handed ENT surgeon faces.

  16. Multiple Coronary Artery Microfistulas Associated with Apical Hypertrophic Cardiomyopathy: Left and Right Coronary Artery to the Left Ventricle

    Directory of Open Access Journals (Sweden)

    Jeong-Woo Choi

    2015-01-01

    Full Text Available A 76-year-old woman underwent coronary angiography for chest pain. On the coronary angiogram, no significant coronary artery atherosclerotic stenosis was observed. Multiple coronary artery microfistulas, draining from the left anterior descending artery to the left ventricle and from the posterior descending artery of the right coronary artery to the left ventricle, were observed. Apical wall thickening and fistula flow from the left anterior descending artery were demonstrated by using transthoracic echocardiography. We describe a rare case of multiple coronary artery microfistulas from the left and right coronary artery to the left ventricle combined with apical hypertrophic cardiomyopathy.

  17. Unusual combination of posterior femoral head dislocation with anterior and posterior wall fractures in the ipsilateral acetabulum.

    Science.gov (United States)

    Chen, Wei; Su, Yanling; Zhang, Yingze; Zhang, Qi; Zheng, Zhanle; Pan, Jinshe

    2010-06-09

    Although hip dislocation combined with acetabular fracture is not an uncommon injury, anterior acetabular wall fractures rarely occur in patients who have posterior fracture-dislocations of the hip. This article presents a unique case of anterior and posterior wall fractures of the ipsilateral acetabulum in a patient who sustained traumatic posterior hip dislocation that resulted from a high-speed motor vehicle accident. The initial imaging evaluation, which did not include the obturator oblique view, revealed no concomitant anterior acetabular wall fracture. Repeated manipulative reductions were unsuccessful in reducing the displaced hip joint. Pelvic computed tomography (CT) scans revealed the initially missed anterior acetabular wall fracture fragments incarcerated in the left hip joint in addition to the hip dislocation and the posterior acetabular wall fracture. The incarcerated bone fragments lay between the anterior wall and the femoral head, and between the posterior wall and the femoral head, which appeared to derive from both anterior and posterior acetabular walls, respectively. Open reduction and internal fixation was performed to manage the posterior dislocation and associated acetabular fractures. Intraoperatively, the major anterior wall fragment was used to reconstruct the defected posterior wall. This case highlights the necessity of suspicion and pre- and postoperative monitoring of the obturator oblique view and CT scans to detect the potentially existing anterior acetabular wall fracture. Early surgical intervention is important to guarantee satisfactory outcomes of such complex fracture-dislocation injuries. Copyright 2010, SLACK Incorporated.

  18. Detecting representations of recent and remote autobiographical memories in vmPFC and hippocampus

    Science.gov (United States)

    Bonnici, Heidi M.; Chadwick, Martin J.; Lutti, Antoine; Hassabis, Demis; Weiskopf, Nikolaus; Maguire, Eleanor A.

    2012-01-01

    How autobiographical memories are represented in the human brain and whether this changes with time are questions central to memory neuroscience. Two regions in particular have been consistently implicated, the ventromedial prefrontal cortex (vmPFC) and the hippocampus, although their precise contributions are still contested. The key question in this debate, when reduced to its simplest form, concerns where information about specific autobiographical memories is located. Here we availed ourselves of the opportunity afforded by multi-voxel pattern analysis (MVPA) to provide an alternative to conventional neuropsychological and fMRI approaches, by detecting representations of individual autobiographical memories in patterns of fMRI activity. We examined whether information about specific recent (two weeks old) and remote (ten years old) autobiographical memories was represented in vmPFC and hippocampus, and other medial temporal and neocortical regions. vmPFC contained information about recent and remote autobiographical memories, although remote memories were more readily detected there, indicating that consolidation or a change of some kind had occurred. Information about both types of memory was also present in the hippocampus, suggesting it plays a role in the retrieval of vivid autobiographical memories regardless of remoteness. Interestingly, we also found that while recent and remote memories were both represented within anterior and posterior hippocampus, the latter nevertheless contained more information about remote memories. Thus, like vmPFC, the hippocampus too respected the distinction between recent and remote memories. Overall, these findings clarify and extend our view of vmPFC and hippocampus while also informing systems-level consolidation and providing clear targets for future studies. PMID:23175849

  19. Neurogenic Effects of Ghrelin on the Hippocampus.

    Science.gov (United States)

    Kim, Chanyang; Kim, Sehee; Park, Seungjoon

    2017-03-08

    Mammalian neurogenesis continues throughout adulthood in the subventricular zone of the lateral ventricle and in the subgranular zone of the dentate gyrus in the hippocampus. It is well known that hippocampal neurogenesis is essential in mediating hippocampus-dependent learning and memory. Ghrelin, a peptide hormone mainly synthesized in the stomach, has been shown to play a major role in the regulation of energy metabolism. A plethora of evidence indicates that ghrelin can also exert important effects on neurogenesis in the hippocampus of the adult brain. The aim of this review is to discuss the current role of ghrelin on the in vivo and in vitro regulation of neurogenesis in the adult hippocampus. We will also discuss the possible role of ghrelin in dietary restriction-induced hippocampal neurogenesis and the link between ghrelin-induced hippocampal neurogenesis and cognitive functions.

  20. Left subclavian artery revascularization as part of thoracic stent grafting

    NARCIS (Netherlands)

    Saouti, N.; Hindori, V.; Morshuis, W.J.; Heijmen, R.H.

    2015-01-01

    OBJECTIVES: Intentional covering of the left subclavian artery (LSA) as part of thoracic endovascular aortic repair (TEVAR) can cause (posterior) strokes or left arm malperfusion. LSA revascularization can be done as prophylaxis against, or as treatment of, these complications. We report our

  1. Posterior Urethral Strictures

    Directory of Open Access Journals (Sweden)

    Joel Gelman

    2015-01-01

    Full Text Available Pelvic fracture urethral injuries are typically partial and more often complete disruptions of the most proximal bulbar and distal membranous urethra. Emergency management includes suprapubic tube placement. Subsequent primary realignment to place a urethral catheter remains a controversial topic, but what is not controversial is that when there is the development of a stricture (which is usually obliterative with a distraction defect after suprapubic tube placement or urethral catheter removal, the standard of care is delayed urethral reconstruction with excision and primary anastomosis. This paper reviews the management of patients who suffer pelvic fracture urethral injuries and the techniques of preoperative urethral imaging and subsequent posterior urethroplasty.

  2. Posterior Urethral Strictures

    Science.gov (United States)

    Gelman, Joel; Wisenbaugh, Eric S.

    2015-01-01

    Pelvic fracture urethral injuries are typically partial and more often complete disruptions of the most proximal bulbar and distal membranous urethra. Emergency management includes suprapubic tube placement. Subsequent primary realignment to place a urethral catheter remains a controversial topic, but what is not controversial is that when there is the development of a stricture (which is usually obliterative with a distraction defect) after suprapubic tube placement or urethral catheter removal, the standard of care is delayed urethral reconstruction with excision and primary anastomosis. This paper reviews the management of patients who suffer pelvic fracture urethral injuries and the techniques of preoperative urethral imaging and subsequent posterior urethroplasty. PMID:26691883

  3. Disrupted functional connectivity of the hippocampus in patients with hyperthyroidism: Evidence from resting-state fMRI

    International Nuclear Information System (INIS)

    Zhang, Wei; Liu, Xianjun; Zhang, Yi; Song, Lingheng; Hou, Jingming; Chen, Bing; He, Mei; Cai, Ping; Lii, Haitao

    2014-01-01

    Objective: The hippocampus expresses high levels of thyroid hormone receptors, suggesting that hippocampal functions, including cognition and regulation of mood, can be disrupted by thyroid pathology. Indeed, structural and functional alterations within the hippocampus have been observed in hyperthyroid patients. In addition to internal circuitry, hippocampal processing is dependent on extensive connections with other limbic and neocortical structures, but the effects of hyperthyroidism on functional connectivity (FC) with these areas have not been studied. The purpose of this study was to investigate possible abnormalities in the FC between the hippocampus and other neural structures in hyperthyroid patients using resting-state fMRI. Methods: Seed-based correlation analysis was performed on resting-state fMRI data to reveal possible differences in hippocampal FC between hyperthyroid patients and healthy controls. Correlation analysis was used to investigate the relationships between the strength of FC in regions showing significant group differences and clinical variables. Results: Compared to controls, hyperthyroid patients showed weaker FC between the bilateral hippocampus and both the bilateral anterior cingulate cortex (ACC) and bilateral posterior cingulate cortex (PCC), as well as between the right hippocampus and right medial orbitofrontal cortex (mOFC). Disease duration was negatively correlated with FC strength between the bilateral hippocampus and bilateral ACC and PCC. Levels of depression and anxiety were negatively correlated with FC strength between the bilateral hippocampus and bilateral ACC. Conclusion: Decreased functional connectivity between the hippocampus and bilateral ACC, PCC, and right mOFC may contribute to the emotional and cognitive dysfunction associated with hyperthyroidism

  4. Disrupted functional connectivity of the hippocampus in patients with hyperthyroidism: Evidence from resting-state fMRI

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wei, E-mail: will.zhang.1111@gmail.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Department of Radiology, Sichuan Provincial Corps Hospital, Chinese People' s Armed Police Forces, Leshan 614000 (China); Liu, Xianjun, E-mail: xianjun6.liu@gmail.com [Department of Radiology, Sichuan Provincial Corps Hospital, Chinese People' s Armed Police Forces, Leshan 614000 (China); Zhang, Yi, E-mail: yi.zhang.0833@gmail.com [Department of Radiology, Sichuan Provincial Corps Hospital, Chinese People' s Armed Police Forces, Leshan 614000 (China); Song, Lingheng, E-mail: songlh1023@hotmail.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Hou, Jingming, E-mail: jingminghou@hotmail.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Chen, Bing, E-mail: chenbing3@medmail.com.cn [Department of Endocrinology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); He, Mei, E-mail: sunnusunny0105@gmail.com [Department of Clinical Psychology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Cai, Ping, E-mail: pingc_ddd@sina.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Lii, Haitao, E-mail: haitaolii023@gmail.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China)

    2014-10-15

    Objective: The hippocampus expresses high levels of thyroid hormone receptors, suggesting that hippocampal functions, including cognition and regulation of mood, can be disrupted by thyroid pathology. Indeed, structural and functional alterations within the hippocampus have been observed in hyperthyroid patients. In addition to internal circuitry, hippocampal processing is dependent on extensive connections with other limbic and neocortical structures, but the effects of hyperthyroidism on functional connectivity (FC) with these areas have not been studied. The purpose of this study was to investigate possible abnormalities in the FC between the hippocampus and other neural structures in hyperthyroid patients using resting-state fMRI. Methods: Seed-based correlation analysis was performed on resting-state fMRI data to reveal possible differences in hippocampal FC between hyperthyroid patients and healthy controls. Correlation analysis was used to investigate the relationships between the strength of FC in regions showing significant group differences and clinical variables. Results: Compared to controls, hyperthyroid patients showed weaker FC between the bilateral hippocampus and both the bilateral anterior cingulate cortex (ACC) and bilateral posterior cingulate cortex (PCC), as well as between the right hippocampus and right medial orbitofrontal cortex (mOFC). Disease duration was negatively correlated with FC strength between the bilateral hippocampus and bilateral ACC and PCC. Levels of depression and anxiety were negatively correlated with FC strength between the bilateral hippocampus and bilateral ACC. Conclusion: Decreased functional connectivity between the hippocampus and bilateral ACC, PCC, and right mOFC may contribute to the emotional and cognitive dysfunction associated with hyperthyroidism.

  5. Alveolar ridge expansion-assisted orthodontic space closure in the mandibular posterior region

    OpenAIRE

    Ozer, Mete; Akdeniz, Berat Serdar; Sumer, Mahmut

    2013-01-01

    Orthodontic closure of old, edentulous spaces in the mandibular posterior region is a major challenge. In this report, we describe a method of orthodontic closure of edentulous spaces in the mandibular posterior region accelerated by piezoelectric decortication and alveolar ridge expansion. Combined piezosurgical and orthodontic treatments were used to close 14- and 15-mm-wide spaces in the mandibular left and right posterior areas, respectively, of a female patient, aged 18 years and 9 month...

  6. Alzheimer's disease and magnetic resonance spectroscopy of the hippocampus

    International Nuclear Information System (INIS)

    Engelhardt, Eliasz; Moreira, Denise M.; Laks, Jerson; Marinho, Valeska M.; Rozenthal, Marcia; Oliveira Junior, Amarino C.

    2001-01-01

    Objective: acquisition of data of magnetic resonance metabolite spectrum of the hippocampal formation (hippocampus-hc) in the elderly, normal and with Alzheimer's disease (AD). Method: Subjects matched for age: a. normal sample (n=20), CDR=0, and b. AD sample (n=40), CDR 1 and 2. Technique: Signa Horizon LX-GE, 1.5T, 1 H-MRS with automated software PROBE/SV, VOI: hc (right and left); single voxel (2x2x2cm); TR 1500ms/TE 50ms; PRESS; metabolites: N-acetylaspartate (Naa), choline (Cho), creatine (Cr), myo-inositol (mI). Results: The present data relate to the ratios of Naa, Cho and mI, with Cr taken as reference, and the mI/Naa ratio. The study showed reduction of Naa, increase of mI and of the mI/Naa ratio, and not consistent results for Cho. The results of the whole sample of AD patients compared to the pooled normal mean ± sd were significant for Naa, mI and mI/Naa (p<0.01). Accuracy in relation to the individual values of both samples showed satisfactory levels of sensitivity, specificity and positive predictive value. Conclusion: The present results can be used as a helpful tool to detect pathologic changes of the hippocampus in AD, and allowing greater accuracy and an earlier diagnosis of this disease. (author)

  7. Posterior ventricular anchoring neochordal repair of degenerative mitral regurgitation efficiently remodels and repositions posterior leaflet prolapse†

    Science.gov (United States)

    Woo, Y. Joseph; MacArthur, John W.

    2013-01-01

    OBJECTIVES Mitral valve repair techniques for degenerative disease typically entail leaflet resection or neochordal construction, which may require extensive resection, leaflet detachment/reattachment, reliance on diseased native chords or precise neochordal measuring. Occasionally, impaired leaflet mobility, reduced coaptation surface and systolic anterior motion (SAM) may result. We describe a novel technique for addressing posterior leaflet prolapse/flail, which both simplifies repair and addresses these issues. METHODS Fifty-four patients (age 62 ± 11 years) with degenerative MR underwent this new repair, 36 of whom minimally-invasively. A CV5 Gore-Tex suture was placed into the posterior left ventricular myocardium underneath the prolapsing segment as an anchor. This suture was then used to imbricate a portion of the prolapsed segment into the ventricle, creating a smooth, broad, non-prolapsed coapting surface on a leaflet with preserved mobility, additional neochordal support and posteriorly positioned enough to preclude SAM. RESULTS Repair was successful in all patients. The mean MR grade was reduced from +3.8 to +0.1 with 50 of 54 patients having zero MR and 4 of the 54 having trace or mild MR. All patients had proper antero-posterior location of the coaptation line of a mean length of 10.2 mm, and preserved posterior leaflet mobility. No patients had SAM or mitral stenosis. All patients were discharged and are currently doing well. CONCLUSION This new technique facilitated efficient single-suture repair of the prolapsed posterior leaflet mitral regurgitation without the need for resection or sliding annuloplasty. It precluded the need for precise neochordal measurement and preserved the leaflet coaptation surface. PMID:23449863

  8. Irreducible Traumatic Posterior Shoulder Dislocation

    Directory of Open Access Journals (Sweden)

    Blake Collier

    2017-01-01

    Full Text Available History of present illness: A 22-year-old male presented to the Emergency Department complaining of right shoulder pain after a motocross accident. He was traveling at approximately 10 mph around a turn when he lost control and was thrown over the handlebars, landing directly on his right shoulder. On arrival, he was holding his arm in adduction and internal rotation. An area of swelling was noted over his anterior shoulder. He was unable to abduct his shoulder. No humeral gapping was noted. He had normal neuro-vascular status distal to the injury. Significant findings: Radiographs demonstrated posterior displacement of the humeral head on the “Y” view (see white arrow and widening of the glenohumeral joint space on anterior-posterior view (see red arrow. The findings were consistent with posterior dislocation and a Hill-Sachs type deformity. Sedation was performed and reduction was attempted using external rotation, traction counter-traction. An immediate “pop” was felt during the procedure. Post-procedure radiographs revealed a persistent posterior subluxation with interlocking at posterior glenoid. CT revealed posterior dislocation with acute depressed impaction deformity medial to the biceps groove with the humeral head perched on the posterior glenoid, interlocked at reverse Hill-Sachs deformity (see blue arrow. Discussion: Posterior shoulder dislocations are rare and represent only 2% of all shoulder dislocations. Posterior shoulder dislocations are missed on initial diagnosis in more than 60% of cases.1 Posterior shoulder dislocations result from axial loading of the adducted and internally rotated shoulder, violent muscle contractions (resulting from seizures or electrocution, a direct posterior force applied to the anterior shoulder.1 Physical findings include decreased anterior prominence of the humeral head, increased palpable posterior prominence of the humeral head below the acromion, increased palpable prominence of the

  9. Subregional Structural Alterations in Hippocampus and Nucleus Accumbens Correlate with the Clinical Impairment in Patients with Alzheimer’s Disease Clinical Spectrum: Parallel Combining Volume and Vertex-Based Approach

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    Xiuling Nie

    2017-08-01

    Full Text Available Deep gray matter structures are associated with memory and other important functions that are impaired in Alzheimer’s disease (AD and mild cognitive impairment (MCI. However, systematic characterization of the subregional atrophy and deformations in these structures in AD and MCI still need more investigations. In this article, we combined complex volumetry- and vertex-based analysis to investigate the pattern of subregional structural alterations in deep gray matter structures and its association with global clinical scores in AD (n = 30 and MCI patients (n = 30, compared to normal controls (NCs, n = 30. Among all seven pairs of structures, the bilateral hippocampi and nucleus accumbens showed significant atrophy in AD compared with NCs (p < 0.05. But only the subregional atrophy in the dorsal–medial part of the left hippocampus, the ventral part of right hippocampus, and the left nucleus accumbens, the posterior part of the right nucleus accumbens correlated with the worse clinical scores of MMSE and MOCA (p < 0.05. Furthermore, the medial–ventral part of right thalamus significantly shrank and correlated with clinical scores without decreasing in its whole volume (p > 0.05. In conclusion, the atrophy of these four subregions in bilateral hippocampi and nucleus accumbens was associated with cognitive impairment of patients, which might be potential target regions of treatment in AD. The surface analysis could provide additional information to volume comparison in finding the early pathological progress in deep gray matter structures.

  10. Cocaine withdrawal causes delayed dysregulation of stress genes in the hippocampus.

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    M Julia García-Fuster

    Full Text Available Relapse, even following an extended period of withdrawal, is a major challenge in substance abuse management. Delayed neurobiological effects of the drug during prolonged withdrawal likely contribute to sustained vulnerability to relapse. Stress is a major trigger of relapse, and the hippocampus regulates the magnitude and duration of stress responses. Recent work has implicated hippocampal plasticity in various aspects of substance abuse. We asked whether changes in stress regulatory mechanisms in the hippocampus may participate in the neuroadaptations that occur during prolonged withdrawal. We therefore examined changes in the rat stress system during the course of withdrawal from extended daily access (5-hours of cocaine self-administration, an animal model of addiction. Tissue was collected at 1, 14 and 28 days of withdrawal. Plasma corticosterone levels were determined and corticosteroid receptors (GR, MR, MR/GR mRNA ratios and expression of other stress-related molecules (HSP90AA1 and HSP90AB1 mRNA were measured in hippocampal subfields using in situ hybridization. Results showed a delayed emergence of dysregulation of stress genes in the posterior hippocampus following 28 days of cocaine withdrawal. This included increased GR mRNA in DG and CA3, increased MR and HSP90AA1 mRNA in DG, and decreased MR/GR mRNA ratio in DG and CA1. Corticosterone levels progressively decreased during the course of withdrawal, were normalized following 28 days of withdrawal, and were correlated negatively with GR and positively with MR/GR mRNA ratio in DG. These results suggest a role for the posterior hippocampus in the neuroadaptations that occur during prolonged withdrawal, and point to a signaling partner of GR, HSP90AA1, as a novel dysregulated target during cocaine withdrawal. These delayed neurobiological effects of extended cocaine exposure likely contribute to sustained vulnerability to relapse.

  11. Cocaine withdrawal causes delayed dysregulation of stress genes in the hippocampus.

    Science.gov (United States)

    García-Fuster, M Julia; Flagel, Shelly B; Mahmood, S Taha; Watson, Stanley J; Akil, Huda

    2012-01-01

    Relapse, even following an extended period of withdrawal, is a major challenge in substance abuse management. Delayed neurobiological effects of the drug during prolonged withdrawal likely contribute to sustained vulnerability to relapse. Stress is a major trigger of relapse, and the hippocampus regulates the magnitude and duration of stress responses. Recent work has implicated hippocampal plasticity in various aspects of substance abuse. We asked whether changes in stress regulatory mechanisms in the hippocampus may participate in the neuroadaptations that occur during prolonged withdrawal. We therefore examined changes in the rat stress system during the course of withdrawal from extended daily access (5-hours) of cocaine self-administration, an animal model of addiction. Tissue was collected at 1, 14 and 28 days of withdrawal. Plasma corticosterone levels were determined and corticosteroid receptors (GR, MR, MR/GR mRNA ratios) and expression of other stress-related molecules (HSP90AA1 and HSP90AB1 mRNA) were measured in hippocampal subfields using in situ hybridization. Results showed a delayed emergence of dysregulation of stress genes in the posterior hippocampus following 28 days of cocaine withdrawal. This included increased GR mRNA in DG and CA3, increased MR and HSP90AA1 mRNA in DG, and decreased MR/GR mRNA ratio in DG and CA1. Corticosterone levels progressively decreased during the course of withdrawal, were normalized following 28 days of withdrawal, and were correlated negatively with GR and positively with MR/GR mRNA ratio in DG. These results suggest a role for the posterior hippocampus in the neuroadaptations that occur during prolonged withdrawal, and point to a signaling partner of GR, HSP90AA1, as a novel dysregulated target during cocaine withdrawal. These delayed neurobiological effects of extended cocaine exposure likely contribute to sustained vulnerability to relapse.

  12. Endoscopic Management of Posterior Epistaxis

    OpenAIRE

    Paul, J.; Kanotra, Sohit Paul; Kanotra, Sonika

    2011-01-01

    The traditional method of management of posterior epistaxis has been with anteroposterior nasal packing. Apart from the high failure rate of 26–50% reported in various series, nasal packing is associated with marked discomfort and several complications. In order to avoid nasal packing, we started doing endoscopic cauterization in cases of posterior epistaxis. A total of 23 patients with posterior epistaxis were subjected to nasal endoscopy with the intent to stop bleeding by cauterization of ...

  13. Mental space travel: damage to posterior parietal cortex prevents egocentric navigation and reexperiencing of remote spatial memories.

    Science.gov (United States)

    Ciaramelli, Elisa; Rosenbaum, R Shayna; Solcz, Stephanie; Levine, Brian; Moscovitch, Morris

    2010-05-01

    The ability to navigate in a familiar environment depends on both an intact mental representation of allocentric spatial information and the integrity of systems supporting complementary egocentric representations. Although the hippocampus has been implicated in learning new allocentric spatial information, converging evidence suggests that the posterior parietal cortex (PPC) might support egocentric representations. To date, however, few studies have examined long-standing egocentric representations of environments learned long ago. Here we tested 7 patients with focal lesions in PPC and 12 normal controls in remote spatial memory tasks, including 2 tasks reportedly reliant on allocentric representations (distance and proximity judgments) and 2 tasks reportedly reliant on egocentric representations (landmark sequencing and route navigation; see Rosenbaum, Ziegler, Winocur, Grady, & Moscovitch, 2004). Patients were unimpaired in distance and proximity judgments. In contrast, they all failed in route navigation, and left-lesioned patients also showed marginally impaired performance in landmark sequencing. Patients' subjective experience associated with navigation was impoverished and disembodied compared with that of the controls. These results suggest that PPC is crucial for accessing remote spatial memories within an egocentric reference frame that enables both navigation and reexperiencing. Additionally, PPC was found to be necessary to implement specific aspects of allocentric navigation with high demands on spontaneous retrieval. PsycINFO Database Record (c) 2010 APA, all rights reserved.

  14. Cervical disc hernia operations through posterior laminoforaminotomy

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    Coskun Yolas

    2016-01-01

    Full Text Available Objective: The most common used technique for posterolateral cervical disc herniations is anterior approach. However, posterior cervical laminotoforaminomy can provide excellent results in appropriately selected patients with foraminal stenosis in either soft disc prolapse or cervical spondylosis. The purpose of this study was to present the clinical outcomes following posterior laminoforaminotomy in patients with radiculopathy. Materials and Methods: We retrospectively evaluated 35 patients diagnosed with posterolateral cervical disc herniation and cervical spondylosis with foraminal stenosis causing radiculopathy operated by the posterior cervical keyhole laminoforaminotomy between the years 2010 and 2015. Results: The file records and the radiographic images of the 35 patients were assessed retrospectively. The mean age was 46.4 years (range: 34-66 years. Of the patients, 19 were males and 16 were females. In all of the patients, the neurologic deficit observed was radiculopathy. The posterolaterally localized disc herniations and the osteophytic structures were on the left side in 18 cases and on the right in 17 cases. In 10 of the patients, the disc level was at C5-6, in 18 at C6-7, in 2 at C3-4, in 2 at C4-5, in 1 at C7-T1, in 1 patient at both C5-6 and C6-7, and in 1 at both C4-5 and C5-6. In 14 of these 35 patients, both osteophytic structures and protruded disc herniation were present. Intervertebral foramen stenosis was present in all of the patients with osteophytes. Postoperatively, in 31 patients the complaints were relieved completely and four patients had complaints of neck pain and paresthesia radiating to the arm (the success of operation was 88.5%. On control examinations, there was no finding of instability or cervical kyphosis. Conclusion: Posterior cervical laminoforaminotomy is an alternative appropriate choice in both cervical soft disc herniations and cervical stenosis.

  15. Unilateral spatial neglect after posterior parietal damage.

    Science.gov (United States)

    Vallar, Giuseppe; Calzolari, Elena

    2018-01-01

    Unilateral spatial neglect is a disabling neurologic deficit, most frequent and severe after right-hemispheric lesions. In most patients neglect involves the left side of space, contralateral to a right-hemispheric lesion. About 50% of stroke patients exhibit neglect in the acute phase. Patients fail to orient, respond to, and report sensory events occurring in the contralateral sides of space and of the body, to explore these portions of space through movements by action effectors (eye, limbs), and to move the contralateral limbs. Neglect is a multicomponent higher-level disorder of spatial awareness, cognition, and attention. Spatial neglect may occur independently of elementary sensory and motor neurologic deficits, but it can mimic and make them more severe. Diagnostic tests include: motor exploratory target cancellation; setting the midpoint of a horizontal line (bisection), that requires the estimation of lateral extent; drawing by copy and from memory; reading, assessing neglect dyslexia; and exploring the side of the body contralateral to the lesion. Activities of daily living scales are also used. Patients are typically not aware of neglect, although they may exhibit varying degrees of awareness toward different components of the deficit. The neural correlates include lesions to the inferior parietal lobule of the posterior parietal cortex, which was long considered the unique neuropathologic correlate of neglect, to the premotor and to the dorsolateral prefrontal cortices, to the posterior superior temporal gyrus, at the temporoparietal junction, to subcortical gray nuclei (thalamus, basal ganglia), and to parietofrontal white-matter fiber tracts, such as the superior longitudinal fascicle. Damage to the inferior parietal lobule of the posterior parietal cortex is specifically associated with the mainly egocentric, perceptual, and exploratory extrapersonal, and with the personal, bodily components of neglect. Productive manifestations, such as

  16. Cervical disc hernia operations through posterior laminoforaminotomy.

    Science.gov (United States)

    Yolas, Coskun; Ozdemir, Nuriye Guzin; Okay, Hilmi Onder; Kanat, Ayhan; Senol, Mehmet; Atci, Ibrahim Burak; Yilmaz, Hakan; Coban, Mustafa Kemal; Yuksel, Mehmet Onur; Kahraman, Umit

    2016-01-01

    The most common used technique for posterolateral cervical disc herniations is anterior approach. However, posterior cervical laminotoforaminomy can provide excellent results in appropriately selected patients with foraminal stenosis in either soft disc prolapse or cervical spondylosis. The purpose of this study was to present the clinical outcomes following posterior laminoforaminotomy in patients with radiculopathy. We retrospectively evaluated 35 patients diagnosed with posterolateral cervical disc herniation and cervical spondylosis with foraminal stenosis causing radiculopathy operated by the posterior cervical keyhole laminoforaminotomy between the years 2010 and 2015. The file records and the radiographic images of the 35 patients were assessed retrospectively. The mean age was 46.4 years (range: 34-66 years). Of the patients, 19 were males and 16 were females. In all of the patients, the neurologic deficit observed was radiculopathy. The posterolaterally localized disc herniations and the osteophytic structures were on the left side in 18 cases and on the right in 17 cases. In 10 of the patients, the disc level was at C5-6, in 18 at C6-7, in 2 at C3-4, in 2 at C4-5, in 1 at C7-T1, in 1 patient at both C5-6 and C6-7, and in 1 at both C4-5 and C5-6. In 14 of these 35 patients, both osteophytic structures and protruded disc herniation were present. Intervertebral foramen stenosis was present in all of the patients with osteophytes. Postoperatively, in 31 patients the complaints were relieved completely and four patients had complaints of neck pain and paresthesia radiating to the arm (the success of operation was 88.5%). On control examinations, there was no finding of instability or cervical kyphosis. Posterior cervical laminoforaminotomy is an alternative appropriate choice in both cervical soft disc herniations and cervical stenosis.

  17. Neuropathologic features in the hippocampus and cerebellum of three older men with fragile X syndrome

    Science.gov (United States)

    2011-01-01

    Background Fragile X syndrome (FXS) is the most common inherited form of intellectual disability, and is the most common single-gene disorder known to be associated with autism. Despite recent advances in functional neuroimaging and our understanding of the molecular pathogenesis, only limited neuropathologic information on FXS is available. Methods Neuropathologic examinations were performed on post-mortem brain tissue from three older men (aged 57, 64 and 78 years) who had received a clinical or genetic diagnosis of FXS. In each case, physical and cognitive features were typical of FXS, and one man was also diagnosed with autism. Guided by reports of clinical and neuroimaging abnormalities of the limbic system and cerebellum of individuals with FXS, the current analysis focused on neuropathologic features present in the hippocampus and the cerebellar vermis. Results Histologic and immunologic staining revealed abnormalities in both the hippocampus and cerebellar vermis. Focal thickening of hippocampal CA1 and irregularities in the appearance of the dentate gyrus were identified. All lobules of the cerebellar vermis and the lateral cortex of the posterior lobe of the cerebellum had decreased numbers of Purkinje cells, which were occasionally misplaced, and often lacked proper orientation. There were mild, albeit excessive, undulations of the internal granular cell layer, with patchy foliar white matter axonal and astrocytic abnormalities. Quantitative analysis documented panfoliar atrophy of both the anterior and posterior lobes of the vermis, with preferential atrophy of the posterior lobule (VI to VII) compared with age-matched normal controls. Conclusions Significant morphologic changes in the hippocampus and cerebellum in three adult men with FXS were identified. This pattern of pathologic features supports the idea that primary defects in neuronal migration, neurogenesis and aging may underlie the neuropathology reported in FXS. PMID:21303513

  18. Tibialis Posterior Tenosynovitis: A Unique Musculoskeletal Manifestation of Gout.

    Science.gov (United States)

    Shupper, Peter; Stitik, Todd P

    2018-02-01

    Extra-articular manifestations of gout can present in several ways, including tenosynovitis. We present a rare case of acute tibialis posterior gouty tenosynovitis. An 82-year-old man with a history of well-controlled gout presented with acute onset of left ankle pain, occurring without inciting event. The medial ankle was slightly erythematous with moderate dorsal-medial swelling and mild dorsal-lateral swelling, with severe tenderness to palpation over the medial retro-malleolar region. Range of motion and manual muscle testing were pain limited throughout. Ultrasound examination revealed a left posterior tibialis tendon sheath tenosynovitis with effusion and overlying soft tissue edema. Tendon sheath aspirate revealed sodium urate crystals and a white blood cell count of 6400/μL. Tendon sheath injection with a mixture of 1% lidocaine and dexamethasone 4 mg resulted in symptom resolution. Repeat ultrasound examination demonstrated no evidence of tibialis posterior tendon sheath effusion. This case is unique not only because acute gouty posterior tibialis tenosynovitis is very rare, particularly in a normouricemic individual, but also because the sonographic evidence of gouty infiltration into the posterior tibialis tendon and overlying subcutaneous tissue considerably aided in arriving at the correct diagnosis in a timely manner.

  19. Predisposing factors in posterior circulation infarcts: a vascular morphological assessment.

    Science.gov (United States)

    Çoban, Gökçen; Çifçi, Egemen; Yildirim, Erkan; Ağıldere, Ahmet Muhteşem

    2015-05-01

    The aim of the study is to assess the effect of shape, diameter, elongation and deviation criteria of basilar artery (BA), convergence angle and diameter variations of vertebral arteries, and concurrent chronic diseases on posterior circulation infarcts. Between January 2010 and May 2013, 186 patients who underwent brain and diffusion magnetic resonance imaging (MRI) with suspected cerebrovascular accident and were diagnosed with posterior circulation infarct and 120 infarct negative control subjects were included in this case-control retrospective study. Vertebral artery (VA) and BA diameter, right (R) and left (L) VA angles at the level of bifurcation, and BA elongation-deviation, and shape of BA were assessed in a total of 306 subjects. Ischemic lesions in the posterior circulation were classified according to their anatomical location and vascular perfusion areas. No significant difference was noted between the control and patient groups with respect to BA diameter (p = 0.676). The most effective risk factors for posterior circulation infarcts were as follows: BA elongation of 2 or 3, BA transverse location of 2 or 3, increase in left VA angle, and history of hypertension, hypercholesterolemia, and diabetes mellitus. Our results suggest that prominent elongation and deviation, C and J shape of BA, and increased L VA angle may be the predictors of at-risk patients in posterior circulation infarcts. Reporting marked morphological BA and VA variations detected at routine brain MRI will aid in selection of patients. Timely detection and treatment of at-risk patients may be life-saving.

  20. Predisposing factors in posterior circulation infarcts: a vascular morphological assessment

    International Nuclear Information System (INIS)

    Coban, Goekcen; Cifci, Egemen; Yildirim, Erkan; Agildere, Ahmet Muhtesem

    2015-01-01

    The aim of the study is to assess the effect of shape, diameter, elongation and deviation criteria of basilar artery (BA), convergence angle and diameter variations of vertebral arteries, and concurrent chronic diseases on posterior circulation infarcts. Between January 2010 and May 2013, 186 patients who underwent brain and diffusion magnetic resonance imaging (MRI) with suspected cerebrovascular accident and were diagnosed with posterior circulation infarct and 120 infarct negative control subjects were included in this case-control retrospective study. Vertebral artery (VA) and BA diameter, right (R) and left (L) VA angles at the level of bifurcation, and BA elongation-deviation, and shape of BA were assessed in a total of 306 subjects. Ischemic lesions in the posterior circulation were classified according to their anatomical location and vascular perfusion areas. No significant difference was noted between the control and patient groups with respect to BA diameter (p = 0.676). The most effective risk factors for posterior circulation infarcts were as follows: BA elongation of 2 or 3, BA transverse location of 2 or 3, increase in left VA angle, and history of hypertension, hypercholesterolemia, and diabetes mellitus. Our results suggest that prominent elongation and deviation, C and J shape of BA, and increased L VA angle may be the predictors of at-risk patients in posterior circulation infarcts. Reporting marked morphological BA and VA variations detected at routine brain MRI will aid in selection of patients. Timely detection and treatment of at-risk patients may be life-saving. (orig.)

  1. Predisposing factors in posterior circulation infarcts: a vascular morphological assessment

    Energy Technology Data Exchange (ETDEWEB)

    Coban, Goekcen; Cifci, Egemen; Yildirim, Erkan; Agildere, Ahmet Muhtesem [Baskent University Faculty of Medicine, Department of Radiology, Konya (Turkey)

    2015-05-01

    The aim of the study is to assess the effect of shape, diameter, elongation and deviation criteria of basilar artery (BA), convergence angle and diameter variations of vertebral arteries, and concurrent chronic diseases on posterior circulation infarcts. Between January 2010 and May 2013, 186 patients who underwent brain and diffusion magnetic resonance imaging (MRI) with suspected cerebrovascular accident and were diagnosed with posterior circulation infarct and 120 infarct negative control subjects were included in this case-control retrospective study. Vertebral artery (VA) and BA diameter, right (R) and left (L) VA angles at the level of bifurcation, and BA elongation-deviation, and shape of BA were assessed in a total of 306 subjects. Ischemic lesions in the posterior circulation were classified according to their anatomical location and vascular perfusion areas. No significant difference was noted between the control and patient groups with respect to BA diameter (p = 0.676). The most effective risk factors for posterior circulation infarcts were as follows: BA elongation of 2 or 3, BA transverse location of 2 or 3, increase in left VA angle, and history of hypertension, hypercholesterolemia, and diabetes mellitus. Our results suggest that prominent elongation and deviation, C and J shape of BA, and increased L VA angle may be the predictors of at-risk patients in posterior circulation infarcts. Reporting marked morphological BA and VA variations detected at routine brain MRI will aid in selection of patients. Timely detection and treatment of at-risk patients may be life-saving. (orig.)

  2. Corresponding erdosteine changes autophagy genes expression in hippocampus on Rhinitis medicamentosa model

    Directory of Open Access Journals (Sweden)

    Dokuyucu Recep

    2015-01-01

    Full Text Available In our study, rats were subjected to Oxymetazoline hydrochloride treatment and Rhinitis medicamentosa (RM was formed and then autophagy gene expression levels were determined after the application of an antioxidant agent erdosteine (ED. The rats were divided into three groups; Group 1 was the control group. Group 2 (RM and group 3 (RM+ED rats received two spray puffs of 0.05% oxymetazoline into the nasal cavities three times daily for eight weeks. After determination of RM in the rats, the RM group were killed. The ED+RM group received 10 mg/kg of an ED suspension. At the end of seven days, these rats were also killed. All groups’ hippocampus tissues were obtained for the measurement of autophagy gene expressions. In rhinitis medicamentosa group Atg5, Atg7 and Atg10 gene expressions in the left hippocampus were reduced as compared to control group (p=0.01, p>0.05, p=0.01, respectively. Also, erdosteine treatments were restored mRNA expression of autophagy genes. In right hippocampus of rhinitis medicamentosa group, Atg5 and Atg10 gene expressions was found to be down-regulated as compared to control group (p>0.05, p<0.05, respectively. Both BECN1 and ULK genes expression were found to be reduced in left hippocampus of rhinitis medicamentosa group. Erdosteine applications was restored the expression of these genes (p=0.03, p=0.03, respectively. Additionally, in right hippocampus, Erdosteine application was restored the expression of ULK gene (p=0.01. This is the first report that evaluated the expression autophagy genes in RM rat models and the changes observed after erdosteine applications.

  3. Hippocampus-dependent learning influences hippocampal neurogenesis.

    Directory of Open Access Journals (Sweden)

    Jonathan Richard Epp

    2013-04-01

    Full Text Available The structure of the mammalian hippocampus continues to be modified throughout life by continuous addition of neurons in the dentate gyrus. Although the existence of adult neurogenesis is now widely accepted, the function that adult generated granule cells play is a topic of intense debate. Many studies have argued that adult generated neurons, due to unique physiological characteristics, play a unique role in hippocampus-dependent learning and memory. However, it is not currently clear whether this is the case or what specific capability adult generated neurons may confer that developmentally generated neurons do not. These questions have been addressed in numerous ways, from increasing and decreasing neurogenesis to computational modeling. One particular area of research has examined the effects of hippocampus dependent learning on proliferation, survival, integration and activation of immature neurons in response to memory retrieval. Within this subfield there remains a range of data showing that hippocampus dependent learning may increase, decrease or alternatively may not alter these factors. Determining how and when hippocampus-dependent learning alters adult neurogenesis will help to further clarify the role of adult generated neurons. There are many variables (such as age of immature neurons, species, strain, sex, stress, task difficulty and type of learning as well as numerous methodological differences (such as marker type, quantification techniques, apparatus size etc. that could all be crucial for a clear understanding of the interaction between learning and neurogenesis. Here, we review these findings and discuss the different conditions under which hippocampus-dependent learning impacts adult neurogenesis in the dentate gyrus.

  4. Hidroma subdural na fossa posterior

    Directory of Open Access Journals (Sweden)

    José Carlos Vasques

    1970-03-01

    Full Text Available Os autores relatam um caso de hidroma subdural na fossa craniana posterior conseqüente a traumatismo na região occipital. O paciente foi operado com pleno sucesso. A raridade da localização de hidroma na fossa posterior é salientada, sendo discutidos os possíveis mecanismos etio-patogênicos.

  5. Complete absence of the posterior arch of C1: Case report

    Directory of Open Access Journals (Sweden)

    R Khanna

    2014-01-01

    Full Text Available Posterior atlas arch anomalies are relatively common, but have a variety of presentations ranging from partial clefts to complete agenesis of the posterior arch. Partial clefts are prevalent in 4% of patients and are generally asymptomatic. However, complete agenesis of the posterior arch is extremely rare. We report the case of a 46-year-old man who presented with upper cervical spine and occipital pain as well as left sided headaches. Imaging revealed congenital complete absence of the posterior arch of C1 (Type E without any radiographic evidence of instability. We discuss our case in light of other reported cases and detail its management.

  6. through the posterior tympanotomy

    Directory of Open Access Journals (Sweden)

    Emilia B. Karchier

    2016-07-01

    Full Text Available Introduction : The anterior epitympanum recess (AER is a common place of the development of the cholesteatoma, which is why removal of the matrix from this area plays a key role in the surgical treatment of chronic otitis media. Aim : To evaluate the intraoperative visibility of AER in endoscopic optics in comparison to microscopic optics and to determine the prevalence of cholesteatoma in various types of construction of the AER. Study design: Retrospective analysis of intraoperative search. Material and methods : The study included 55 patients treated in the Department of Otolaryngology, Medical University of Warsaw within the years 2009–2011, who underwent endoscopy-assisted canal wall up tympanoplasty with posterior tympanotomy. The type of construction of the AER – cellular or dome-shaped – was determined. Results : Cellular type of recess was found intraoperatively in 32% of ears and dome-shaped in 68% of the study group. The population with chronic otitis media does not differ significantly compared to the general population in terms of the construction of the anterior epitympanum recess (p = 0.668108; χ 2 = 0.1838235, df = 1. Among the ears with cholesteatoma a cellular AER was found in 48.3% of cases and a dome-shaped AER was found in 51.7%. Conclusions : The cellular type of AER was significantly more frequent in ears with cholesteatoma (p < 0.01, χ 2 = 29.86492, df = 1. Level of evidence: 1b.

  7. Andrographolide Stimulates Neurogenesis in the Adult Hippocampus

    Directory of Open Access Journals (Sweden)

    Lorena Varela-Nallar

    2015-01-01

    Full Text Available Andrographolide (ANDRO is a labdane diterpenoid component of Andrographis paniculata widely used for its anti-inflammatory properties. We have recently determined that ANDRO is a competitive inhibitor of glycogen synthase kinase-3β (GSK-3β, a key enzyme of the Wnt/β-catenin signaling cascade. Since this signaling pathway regulates neurogenesis in the adult hippocampus, we evaluated whether ANDRO stimulates this process. Treatment with ANDRO increased neural progenitor cell proliferation and the number of immature neurons in the hippocampus of 2- and 10-month-old mice compared to age-matched control mice. Moreover, ANDRO stimulated neurogenesis increasing the number of newborn dentate granule neurons. Also, the effect of ANDRO was evaluated in the APPswe/PS1ΔE9 transgenic mouse model of Alzheimer’s disease. In these mice, ANDRO increased cell proliferation and the density of immature neurons in the dentate gyrus. Concomitantly with the increase in neurogenesis, ANDRO induced the activation of the Wnt signaling pathway in the hippocampus of wild-type and APPswe/PS1ΔE9 mice determined by increased levels of β-catenin, the inactive form of GSK-3β, and NeuroD1, a Wnt target gene involved in neurogenesis. Our findings indicate that ANDRO stimulates neurogenesis in the adult hippocampus suggesting that this drug could be used as a therapy in diseases in which neurogenesis is affected.

  8. Mind-body problem and hippocampus.

    Science.gov (United States)

    Behrendt, Ralf-Peter

    2017-09-01

    Commentary on Faw's comprehensive response to a previous commentary ('Hippocampus as a wormhole' by Ralf-Peter Behrendt, doi: 10.1002/wcs.1446) on Faw and Faw's paper (doi: 10.1002/wcs.1412). WIREs Cogn Sci 2017, e1447. doi: 10.1002/wcs.1447. © 2017 Wiley Periodicals, Inc.

  9. Coordinating different representations in the hippocampus

    Czech Academy of Sciences Publication Activity Database

    Kelemen, Eduard; Fenton, A.A.

    2016-01-01

    Roč. 129, Mar 2016 (2016), s. 50-59 ISSN 1074-7427 R&D Projects: GA ČR(CZ) GA14-03627S Institutional support: RVO:67985823 Keywords : dynamic functional grouping * multiple representations * cognitive control * hippocampus * overdispersion Subject RIV: FH - Neurology Impact factor: 3.543, year: 2016

  10. Does the endangered Knysna seahorse, Hippocampus capensis ...

    African Journals Online (AJOL)

    Abstract. The Knysna seahorse, Hippocampus capensis, is an endangered teleost confined to three South African estuaries. Its abundance within these systems is low and distributions are patchy. Consequently, monitoring population sizes is labour- intensive. The aim of this study was to establish if Knynsa seahorses are ...

  11. The Progression of Posterior Cortical Atrophy to Corticobasal Syndrome: Lumping or Splitting Neurodegenerative Diseases?

    Directory of Open Access Journals (Sweden)

    Maurizio Giorelli

    2014-06-01

    Full Text Available Background: Posterior cortical atrophy is a clinical syndrome that is characterized by the progressive loss of visuospatial integration and is associated with neurodegenerative conditions.Case Report: We describe a 60‐year‐old female with simultanagnosia, oculomotor apraxia, and optic ataxia for which she received an initial clinical diagnosis of posterior cortical atrophy. Three years later, she developed Balint's syndrome, Gerstmann's syndrome, left alien hand syndrome, smooth asymmetric (left rigidity, cortical sensory loss, and spontaneous myoclonic jerks of the left arm, which suggested a final diagnosis of corticobasal syndrome.Discussion: This case report indicates that corticobasal syndrome may present with visuospatial deficits.

  12. Posterior Coronary Vein as the Substrate for an Epicardial Accessory Pathway

    Directory of Open Access Journals (Sweden)

    Laura Cipoletta, MD

    2013-07-01

    Full Text Available Catheter ablation of Wolff-Parkinson-White syndrome is associated with up to 5% of failure. Coronary sinus (CS abnormalities or connections between CS myocardial coat and left ventricular epicardium are associated with posteroseptal and left posterior accessory pathways (AP. A 41-year-old patient with WPW syndrome was referred to our hospital after three unsuccessful ablations. The 12-lead ECG suggested a left posteroseptal AP. CT imaging and electro-anatomic mapping showed a relationship between AP electrical course and CS posterior branch. This finding supports the hypothesis CSAPs lie in the myocardial coat around CS and represent an extensive connection between atrial and ventricular epicardial surface.

  13. Classification of posterior vitreous detachment

    Science.gov (United States)

    Kakehashi, Akihiro; Takezawa, Mikiko; Akiba, Jun

    2014-01-01

    Diagnosing a posterior vitreous detachment (PVD) is important for predicting the prognosis and determining the indication for vitreoretinal surgery in many vitreoretinal diseases. This article presents both classifications of a PVD by slit-lamp biomicroscopy and of a shallow PVD by optical coherence tomography (OCT). By biomicroscopy, the vitreous condition is determined based on the presence or absence of a PVD. The PVD then is classified as either a complete posterior vitreous detachment (C-PVD) or a partial posterior vitreous detachment (P-PVD). A C-PVD is further divided into a C-PVD with collapse and a C-PVD without collapse, while a P-PVD is divided into a P-PVD with shrinkage of the posterior hyaloid membrane (P-PVD with shrinkage) and a P-PVD without shrinkage of the posterior hyaloid membrane (P-PVD without shrinkage). A P-PVD without shrinkage has a subtype characterized by vitreous gel attachment through the premacular hole in a posterior hyaloid membrane to the macula (P-PVD without shrinkage [M]). By OCT, a shallow PVD is classified as the absence of a shallow PVD or as a shallow PVD. A shallow PVD is then subclassified as a shallow PVD without shrinkage of the posterior vitreous cortex, a shallow PVD with shrinkage of the posterior vitreous cortex, and a peripheral shallow PVD. A shallow PVD without shrinkage of the posterior vitreous cortex has two subtypes: an age-related shallow PVD and a perifoveal PVD associated with a macular hole. PMID:24376338

  14. Endogenous synthesis of corticosteroids in the hippocampus.

    Directory of Open Access Journals (Sweden)

    Shimpei Higo

    Full Text Available BACKGROUND: Brain synthesis of steroids including sex-steroids is attracting much attention. The endogenous synthesis of corticosteroids in the hippocampus, however, has been doubted because of the inability to detect deoxycorticosterone (DOC synthase, cytochrome P450(c21. METHODOLOGY/PRINCIPAL FINDINGS: The expression of P450(c21 was demonstrated using mRNA analysis and immmunogold electron microscopic analysis in the adult male rat hippocampus. DOC production from progesterone (PROG was demonstrated by metabolism analysis of (3H-steroids. All the enzymes required for corticosteroid synthesis including P450(c21, P450(2D4, P450(11β1 and 3β-hydroxysteroid dehydrogenase (3β-HSD were localized in the hippocampal principal neurons as shown via in situ hybridization and immunoelectron microscopic analysis. Accurate corticosteroid concentrations in rat hippocampus were determined by liquid chromatography-tandem mass spectrometry. In adrenalectomized rats, net hippocampus-synthesized corticosterone (CORT and DOC were determined to 6.9 and 5.8 nM, respectively. Enhanced spinogenesis was observed in the hippocampus following application of low nanomolar (10 nM doses of CORT for 1 h. CONCLUSIONS/SIGNIFICANCE: These results imply the complete pathway of corticosteroid synthesis of 'pregnenolone →PROG→DOC→CORT' in the hippocampal neurons. Both P450(c21 and P450(2D4 can catalyze conversion of PROG to DOC. The low nanomolar level of CORT synthesized in hippocampal neurons may play a role in modulation of synaptic plasticity, in contrast to the stress effects by micromolar CORT from adrenal glands.

  15. A case of giant nodular posterior scleritis mimicking choroidal malignancy.

    Science.gov (United States)

    Liu, Andrea T; Luk, Fiona O; Chan, Carmen K

    2015-12-01

    To report a case of giant nodular posterior scleritis mimicking a choroidal tumor. A 42-year-old lady with systemic hypertension presented with a 1-week history of unilateral visual loss, pain and redness in her left eye. Examination showed sectoral anterior episcleritis in her left eye as well as a dome-shaped choroidal mass at the inferior-temporal periphery, associated with retinal hemorrhages and subretinal fluid. Systemic evaluation and imaging of the choroidal mass were performed and could not rule out amelanotic choroidal melanoma. At the same time, she was prescribed a 2-week course of oral nonsteroidal anti-inflammatory drug (NSAID) for her sectoral anterior episcleritis. The choroidal mass was found to have resolved completely right before her scheduled fine needle biopsy. Diagnosis of nodular posterior scleritis and a trial of oral NSAID can be considered in patients presenting with a choroidal mass before any invasive procedure.

  16. A case of giant nodular posterior scleritis mimicking choroidal malignancy

    Directory of Open Access Journals (Sweden)

    Andrea T Liu

    2015-01-01

    Full Text Available To report a case of giant nodular posterior scleritis mimicking a choroidal tumor. A 42-year-old lady with systemic hypertension presented with a 1-week history of unilateral visual loss, pain and redness in her left eye. Examination showed sectoral anterior episcleritis in her left eye as well as a dome-shaped choroidal mass at the inferior-temporal periphery, associated with retinal hemorrhages and subretinal fluid. Systemic evaluation and imaging of the choroidal mass were performed and could not rule out amelanotic choroidal melanoma. At the same time, she was prescribed a 2-week course of oral nonsteroidal anti-inflammatory drug (NSAID for her sectoral anterior episcleritis. The choroidal mass was found to have resolved completely right before her scheduled fine needle biospy. Diagnosis of nodular posterior scleritis and a trial of oral NSAID can be considered in patients presenting with a choroidal mass before any invasive procedure.

  17. [Diagnosis and management of posterior urethra disruptions].

    Science.gov (United States)

    Bensalah, K; Manunta, A; Guillé, F; Patard, J J

    2006-10-01

    Rupture of posterior urethra is usually seen in major traumas with associated pelvic fractures. Clinical presentation classically associates blood at the uretral meatus and urinary retention. Urinary diversion should be achieved by suprapubic puncture and major associated traumatic injuries (abdominal, orthopaedic, and neurological lesions) must be treated prior to urological management. Retrograde uretrocystography is performed a few days later in order to localize and classify the urethral lesion. Treatment of posterior urethral ruptures has evolved over the years. Immediate open repair is no longer recommended. The supra-pubic catheter can be left in place until resorption of the pelvic hematoma. Obliteration occurs in 100% of the cases and is treated by open surgery at 3 months. More and more patients are treated by early endoscopic realignment which has diminished by half the incidence of urethral strictures. Impotence and incontinence secondary to trauma or surgery occur in 20% and 10% of the patients respectively. Long term follow-up should be achieved in every patient.

  18. Variations of posterior vitreous detachment

    OpenAIRE

    Kakehashi, A.; Kado, M.; Akiba, J.; Hirokawa, H.

    1997-01-01

    AIMS—To identify variations in posterior vitreous detachment (PVD) and establish a clinical classification system for PVD.
METHODS—400 consecutive eyes were examined using biomicroscopy and vitreous photography and classified the PVD variations—complete PVD with collapse, complete PVD without collapse, partial PVD with thickened posterior vitreous cortex (TPVC), or partial PVD without TPVC.
RESULTS—In each PVD type, the most frequently seen ocular pathologies were as follows: in complete PVD ...

  19. Semantic dementia and the left and right temporal lobes.

    Science.gov (United States)

    Snowden, Julie S; Harris, Jennifer M; Thompson, Jennifer C; Kobylecki, Christopher; Jones, Matthew; Richardson, Anna M; Neary, David

    2017-08-31

    Semantic dementia, a circumscribed disorder of semantic knowledge, provides a unique model for understanding the neural basis for semantic representation. The study addressed areas of contention: the relative roles of the left and right temporal lobe, the contribution of anterior versus posterior temporal cortex and the status of the anterior temporal lobes as amodal hub. Naming and word comprehension was examined in 41 semantic dementia patients, 31 with left-predominant and 10 right-predominant atrophy. In keeping with expectation, naming and comprehension were significantly poorer in left-predominant patients. Structural magnetic resonance image analysis, using a visual rating scale, showed strong inverse correlations between naming scores and severity of both left anterior and posterior temporal lobe atrophy. By contrast, comprehension performance was more strongly correlated with left posterior temporal atrophy. Analysis of naming errors revealed a correlation between anterior temporal atrophy and associative/functional descriptive responses, implying availability of semantic information. By contrast, 'don't know' responses, indicative of loss of semantic knowledge, were linked to left posterior temporal lobe atrophy. Semantic errors, the hallmark of semantic dementia, were linked to right hemisphere atrophy, especially the right posterior temporal lobe. Matched visual-verbal tasks (famous face and name identification, Pyramids and Palm trees pictures and words, animal knowledge from 3-D models and animal names) administered to nine patients elicited variable correspondence between performance on nonverbal and verbal versions of the task. Marked performance dissociations were demonstrated in some patients: poorer understanding of names/words in left-predominant patients and of faces/pictures/models in right-predominant cases. The findings are compatible with the notion of the anterior temporal lobes as areas of convergence, but are less easily accommodated

  20. Evaluation of mandibular condyles in children with unilateral posterior crossbite.

    Science.gov (United States)

    Illipronti-Filho, Edson; Fantini, Solange Mongelli de; Chilvarquer, Israel

    2015-01-01

    The relationship of mandibular condyle dimensions and its association with unilateral posterior crossbite (UPXB) has been suggested in the literature. The purpose of this prospective study was to evaluate mandibular condyles on the left and right sides and between crossed and non-crossed sides in the sagittal and coronal planes, using cone-beam computed tomography (CBCT). Twenty CBCT images of 40 temporo mandibular joints (TMJs) in individuals in mixed dentition phase, which included 9 males (mean 7.9 years) and 11 females (mean 8.2 years), with unilateral posterior crossbite without premature contacts and functional mandibular shifts and with transverse maxillary deficiency. The criteria for sample exclusion included the presence of painful symptoms, facial trauma history, systemic diseases such as juvenile rheumatoid arthritis, mouth opening limitation (anomalies, and skeletal asymmetries that may result in TMJ disorders. Dimensional measurements of the condyles between the right and left sides and crossed and non-crossed sides in sagittal and coronal view were made. There was no significant difference between the measurements of the crossed and non-crossed sides in both sagittal and coronal view. These findings suggest that the presence of unilateral posterior crossbite in children with UPXB did not result in changes between the mandibular condyles in the right and left sides or between the crossed and non-crossed sides in the coronal or sagittal plane.

  1. Evaluation of mandibular condyles in children with unilateral posterior crossbite

    Directory of Open Access Journals (Sweden)

    Edson ILLIPRONTI-FILHO

    2015-01-01

    Full Text Available The relationship of mandibular condyle dimensions and its association with unilateral posterior crossbite (UPXB has been suggested in the literature. The purpose of this prospective study was to evaluate mandibular condyles on the left and right sides and between crossed and non-crossed sides in the sagittal and coronal planes, using cone-beam computed tomography (CBCT. Twenty CBCT images of 40 temporo mandibular joints (TMJs in individuals in mixed dentition phase, which included 9 males (mean 7.9 years and 11 females (mean 8.2 years, with unilateral posterior crossbite without premature contacts and functional mandibular shifts and with transverse maxillary deficiency. The criteria for sample exclusion included the presence of painful symptoms, facial trauma history, systemic diseases such as juvenile rheumatoid arthritis, mouth opening limitation (< 40 mm, congenital or genetic anomalies, and skeletal asymmetries that may result in TMJ disorders. Dimensional measurements of the condyles between the right and left sides and crossed and non-crossed sides in sagittal and coronal view were made. There was no significant difference between the measurements of the crossed and non-crossed sides in both sagittal and coronal view. These findings suggest that the presence of unilateral posterior crossbite in children with UPXB did not result in changes between the mandibular condyles in the right and left sides or between the crossed and non-crossed sides in the coronal or sagittal plane.

  2. Impact of video games on plasticity of the hippocampus.

    Science.gov (United States)

    West, G L; Konishi, K; Diarra, M; Benady-Chorney, J; Drisdelle, B L; Dahmani, L; Sodums, D J; Lepore, F; Jolicoeur, P; Bohbot, V D

    2017-08-08

    The hippocampus is critical to healthy cognition, yet results in the current study show that action video game players have reduced grey matter within the hippocampus. A subsequent randomised longitudinal training experiment demonstrated that first-person shooting games reduce grey matter within the hippocampus in participants using non-spatial memory strategies. Conversely, participants who use hippocampus-dependent spatial strategies showed increased grey matter in the hippocampus after training. A control group that trained on 3D-platform games displayed growth in either the hippocampus or the functionally connected entorhinal cortex. A third study replicated the effect of action video game training on grey matter in the hippocampus. These results show that video games can be beneficial or detrimental to the hippocampal system depending on the navigation strategy that a person employs and the genre of the game.Molecular Psychiatry advance online publication, 8 August 2017; doi:10.1038/mp.2017.155.

  3. Functional neurogenesis in the adult hippocampus

    Science.gov (United States)

    van Praag, Henriette; Schinder, Alejandro F.; Christie, Brian R.; Toni, Nicolas; Palmer, Theo D.; Gage, Fred H.

    2002-02-01

    There is extensive evidence indicating that new neurons are generated in the dentate gyrus of the adult mammalian hippocampus, a region of the brain that is important for learning and memory. However, it is not known whether these new neurons become functional, as the methods used to study adult neurogenesis are limited to fixed tissue. We use here a retroviral vector expressing green fluorescent protein that only labels dividing cells, and that can be visualized in live hippocampal slices. We report that newly generated cells in the adult mouse hippocampus have neuronal morphology and can display passive membrane properties, action potentials and functional synaptic inputs similar to those found in mature dentate granule cells. Our findings demonstrate that newly generated cells mature into functional neurons in the adult mammalian brain.

  4. Neurobiological toxicity of radiation in hippocampus

    Energy Technology Data Exchange (ETDEWEB)

    Son, Yeong Hoon; Kim, Joong Sun [Research center, Dongnam institute of radiological and Medical Sciences (DIRAMS), Busan (Korea, Republic of); Kim, Sung Ho; Moon, Chang Jong [College of Veterinary Medicine, Chonnam National University, Gwangju (Korea, Republic of)

    2014-11-15

    Ionizing radiation affects multiple organs, which differ in their apparent response. Nevertheless, the adult brain is less vulnerable to radiation than other radiosensitive organs. Clinically, patients receive partial large-field or whole-brain irradiation for cancer treatment yearly, long-term survivors increases, and thus, radiation induced side effects, including cognitive impairment, will become a major health problem. Although the most commonly reported noxious effects of irradiation occur via damage to DNA and consequent disruption of protein synthesis, there are also specific effects on biochemical pathways that have indirect effects on DNA transcription. The hippocampus dependent memory dysfunction is consistent with the changes in neurogenesis after 1 and 3 dyas after irradiation. At 30 and 90 days following irradiation, mice displayed significant depression-like behaviors. Hippocampal dysfunction during the chronic phase following cranial irradiation may be associated with decreases in the neurogenesis and synaptic plasticity related signals, concomitant with microglial reduction in the hippocampus.

  5. Neurobiological toxicity of radiation in hippocampus

    International Nuclear Information System (INIS)

    Son, Yeong Hoon; Kim, Joong Sun; Kim, Sung Ho; Moon, Chang Jong

    2014-01-01

    Ionizing radiation affects multiple organs, which differ in their apparent response. Nevertheless, the adult brain is less vulnerable to radiation than other radiosensitive organs. Clinically, patients receive partial large-field or whole-brain irradiation for cancer treatment yearly, long-term survivors increases, and thus, radiation induced side effects, including cognitive impairment, will become a major health problem. Although the most commonly reported noxious effects of irradiation occur via damage to DNA and consequent disruption of protein synthesis, there are also specific effects on biochemical pathways that have indirect effects on DNA transcription. The hippocampus dependent memory dysfunction is consistent with the changes in neurogenesis after 1 and 3 dyas after irradiation. At 30 and 90 days following irradiation, mice displayed significant depression-like behaviors. Hippocampal dysfunction during the chronic phase following cranial irradiation may be associated with decreases in the neurogenesis and synaptic plasticity related signals, concomitant with microglial reduction in the hippocampus

  6. Social memory engram in the hippocampus.

    Science.gov (United States)

    Okuyama, Teruhiro

    2017-06-01

    Social memory is one of the crucial components of episodic memories. Gregarious animals living in societies utilize social memory to exhibit the appropriate social behaviors such as aggression, avoidance, cooperative behavior, and even mating behavior. However, the neural mechanisms underlying social memory in the hippocampus remains mysterious. Here, I review some evidence from work done in rodents and primates on the brain region(s) and circuits encoding and/or retrieving social memory, as well as a storage for social memory (i.e. social memory engram neurons). Based on our recent findings that neural ensemble in ventral CA1 sub-region of the hippocampus possesses social memory engram, I would discuss the neural network for social information processing in order to encode social memory; and its evolutionary conservation between rodents and human. Copyright © 2017. Published by Elsevier B.V.

  7. Posterior transodontoid fixation: A new fixation (Kotil technique

    Directory of Open Access Journals (Sweden)

    Kadir Kotil

    2011-01-01

    Full Text Available Anterior odontoid screw fixation or posterior C1-2 fusion techniques are routinely used in the treatment of Type II odontoid fractures, but these techniques may be inadequate in some types of odontoid fractures. In this new technique (Kotil technique, through a posterior bilateral approach, transarticular screw fixation was performed at the non-dominant vertebral artery (VA side and posterior transodontoid fixation technique was performed at the dominant VA side. C1-2 complex fusion was aimed with unilateral transarticular fixation and odontoid fixation with posterior transodontoid screw fixation. Cervical spinal computed tomography (CT of a 40-year-old male patient involved in a motor vehicle accident revealed an anteriorly dislocated Type II oblique dens fracture, not reducible by closed traction. Before the operation, the patient was found to have a dominant right VA with Doppler ultrasound. He was operated through a posterior approach. At first, transarticular screw fixation was performed at the non-dominant (left side, and then fixation of the odontoid fracture was achieved by directing the contralateral screw (supplemental screw medially and toward the apex. Cancellous autograft was scattered for fusion without the need for structural bone graft or wiring. Postoperative cervical spinal CT of the patient revealed that stabilization was maintained with transarticular screw fixation and reduction and fixation of the odontoid process was achieved completely by posterior transodontoid screw fixation. The patient is at the sixth month of follow-up and complete fusion has developed. With this new surgical technique, C1-2 fusion is maintained with transarticular screw fixation and odontoid process is fixed by concomitant contralateral posterior transodontoid screw (supplemental screw fixation; thus, this technique both stabilizes the C1-2 complex and fixes the odontoid process and the corpus in atypical odontoid fractures, appearing as an

  8. Neural activity in the hippocampus predicts individual visual short-term memory capacity.

    Science.gov (United States)

    von Allmen, David Yoh; Wurmitzer, Karoline; Martin, Ernst; Klaver, Peter

    2013-07-01

    Although the hippocampus had been traditionally thought to be exclusively involved in long-term memory, recent studies raised controversial explanations why hippocampal activity emerged during short-term memory tasks. For example, it has been argued that long-term memory processes might contribute to performance within a short-term memory paradigm when memory capacity has been exceeded. It is still unclear, though, whether neural activity in the hippocampus predicts visual short-term memory (VSTM) performance. To investigate this question, we measured BOLD activity in 21 healthy adults (age range 19-27 yr, nine males) while they performed a match-to-sample task requiring processing of object-location associations (delay period  =  900 ms; set size conditions 1, 2, 4, and 6). Based on individual memory capacity (estimated by Cowan's K-formula), two performance groups were formed (high and low performers). Within whole brain analyses, we found a robust main effect of "set size" in the posterior parietal cortex (PPC). In line with a "set size × group" interaction in the hippocampus, a subsequent Finite Impulse Response (FIR) analysis revealed divergent hippocampal activation patterns between performance groups: Low performers (mean capacity  =  3.63) elicited increased neural activity at set size two, followed by a drop in activity at set sizes four and six, whereas high performers (mean capacity  =  5.19) showed an incremental activity increase with larger set size (maximal activation at set size six). Our data demonstrated that performance-related neural activity in the hippocampus emerged below capacity limit. In conclusion, we suggest that hippocampal activity reflected successful processing of object-location associations in VSTM. Neural activity in the PPC might have been involved in attentional updating. Copyright © 2013 Wiley Periodicals, Inc.

  9. The flexible use of multiple cue relationships in spatial navigation : A comparison of water maze performance following hippocampal, medial septal, prefrontal cortex, or posterior parietal cortex lesions

    NARCIS (Netherlands)

    Compton, DM; Griffith, HR; McDaniel, WF; Foster, RA; Davis, BK

    Rats prepared with lesions of the prefrontal cortex, posterior parietal cortex, hippocampus, or medial septal area were tested for acquisition of a number of variations of the open-field water maze using a version of place learning assessment described by Eichenbaum, Stewart, and Morris (1991).

  10. [Vectorcardiographic manifestations of left intraventricular conduction disorders].

    Science.gov (United States)

    de Micheli, A; Medrano, G A

    1979-01-01

    Both, the vectorcardiographic changes produced by the various degrees of left bundle branch block and these observed with the different types of left distal block, are described. When a "wave jumping" phenomenon exists, the vectorcardiographic changes are more characteristic in the horizontal plane than in the frontal plane and can be interpreted satisfactorily in basis of the ventricular activation sequence. The normal counterclockwise rotation of the horizontal vectorcardiogram persists in the presence of left bundle branch block of slight and moderate degrees, since the electromotive forces of the free left ventricular wall are still predominant. In the majority of intermediate degree blocks, the middle portion of the RH loop develops with a clockwise rotation and general aspect with a clockwise rotation and the general aspect of the ventricular loop resembles an eight figure. This is due to the electromotive forces originated by the delayed depolarization of the left septal mass that starts to predominate. With advanced degrees of block, the largest portion of the RH loop shows a clockwise rotation, as well as marked notchings and slurrings. The initial anterior portion of the horizontal vectorcardiogram does not disappear, but is situated to the left of the anterior-posterior axis with a counterclockwise rotation (first right septal vector). Otherwise, the direct electrical sign of left distal block emphasized: evidence of delayed activation in a limited zone of the homolateral ventricle. This local delay gives rise to an asynchronism of the activation phenomenon between the upper and lower regions of the ventricle. The diagnosis of left bifascicular block is based essentially on the evidence of unequal delay of the activation sequence in the basal regions and in the inferior ones of the homolateral ventricle and also on the frequent persistence of the first left septal vector.

  11. Effects of fluoxetine on the amygdala and the hippocampus after administration of a single prolonged stress to male Wistar rates: In vivo proton magnetic resonance spectroscopy findings.

    Science.gov (United States)

    Han, Fang; Xiao, Bing; Wen, Lili; Shi, Yuxiu

    2015-05-30

    Posttraumatic stress disorder (PTSD) is an anxiety- and memory-based disorder. The hippocampus and amygdala are key areas in mood regulation. Fluoxetine was found to improve the anxiety-related symptoms of PTSD patients. However, little work has directly examined the effects of fluoxetine on the hippocampus and the amygdala. In the present study, male Wistar rats received fluoxetine or vehicle after exposure to a single prolonged stress (SPS), an animal model of PTSD. In vivo proton magnetic resonance spectroscopy ((1)H-MRS) was performed -1, 1, 4, 7 and 14 days after SPS to examine the effects of fluoxetine on neurometabolite changes in amygdala, hippocampus and thalamus. SPS increased the N-acetylaspartate (NAA)/creatine (Cr) and choline moieties (Cho)/Cr ratios in the bilateral amygdala on day 4, decreased the NAA/Cr ratio in the left hippocampus on day 1, and increased both ratios in the right hippocampus on day 14. But no significant change was found in the thalamus. Fluoxetine treatment corrected the SPS increases in the NAA/Cr and Cho/Cr levels in the amygdala on day 4 and in the hippocampus on day 14, but it failed to normalise SPS-associated decreases in NAA/Cr levels in the left hippocampus on day 1. These results suggested that metabolic abnormalities in the amygdala and the hippocampus were involved in SPS, and different effects of fluoxetine in correcting SPS-induced neurometabolite changes among the three areas. These findings have implications for fluoxetine treatment in PTSD. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  12. Posterior Reversible Leukoencephalopathy Syndrome Associated with Pazopanib

    Directory of Open Access Journals (Sweden)

    Robert Foerster

    2013-04-01

    Full Text Available A 62-year-old female patient with metastatic renal cell carcinoma under third-line treatment with pazopanib for 8 weeks suddenly developed severe headaches, grand mal seizures and paresis of the left arm in combination with gait instability as well as nausea and vomiting during her vacation abroad. The emergency physician measured systolic blood pressure values over 300 mm Hg and suspected a stroke. The CT imaging without contrast agent in a local hospital did not show any pathologic findings despite bone metastases. The colleagues suspected cerebral metastases or meningeosis carcinomatosa and referred the patient to our department for further diagnostics and treatment planning. An MRI scan ruled out the suspected cerebral metastases or meningeosis carcinomatosa, but showed signs of reversible posterior leukoencephalopathy syndrome (RPLS in the form of band-like hyperintensities as a sign of cytotoxic edema in the gray and white matter of the left parietal lobe. The patient then reported that similar blood pressure values had been measured shortly after the start of a first-line therapy with sunitinib, so that we discontinued the current treatment with pazopanib. Within 6 days the neurologic symptoms vanished and the patient was discharged. An intermittent hypertension persisted. A follow-up MRI 3 weeks later showed an RPLS-typical cortical infarction in the affected area. RPLS should be considered as the actual reason for neurologic findings in hypertensive patients with known metastatic cancers under tyrosine kinase inhibitor therapy.

  13. Endoscopic management of posterior epistaxis.

    Science.gov (United States)

    Paul, J; Kanotra, Sohit Paul; Kanotra, Sonika

    2011-04-01

    The traditional method of management of posterior epistaxis has been with anteroposterior nasal packing. Apart from the high failure rate of 26-50% reported in various series, nasal packing is associated with marked discomfort and several complications. In order to avoid nasal packing, we started doing endoscopic cauterization in cases of posterior epistaxis. A total of 23 patients with posterior epistaxis were subjected to nasal endoscopy with the intent to stop bleeding by cauterization of the bleeding vessel. Of these, in four cases unsuspected diagnosis was made. Of the remaining 19, in three patients, the bleeding point could not be localized accurately and these patients were managed by anteroposterior packing. The rest of the 16 patients were managed by endoscopic cauterization. In four patients, there was recurrence of bleeding within 24 h. In one of these, cauterization controlled the bleeding while in the rest nasal packing had to be resorted to. Thus, of the 23 patients of posterior epistaxis subjected to nasal endoscopy, we could avoid nasal packing in 17 (74%). To conclude, endoscopic nasal cauterization is recommended as the first line to treatment in all cases of posterior epistaxis. This will not only prevent the uncomfortable and potentially dangerous nasal packing but also help in finding the underlying pathology.

  14. Perawatan Crossbite Posterior pada Maloklusi Angle Klas III dengan Alat Ortodontik Cekat Teknik Begg

    Directory of Open Access Journals (Sweden)

    Trio Wijayanto

    2011-12-01

    Full Text Available Latar Belakang: Crossbite posterior merupakan hubungan abnormal dari gigi-gigi posterior secara bukolingual pada rahang atas atau bawah pada saat kedua lengkung gigi berada dalam oklusi sentrik yang dapat terjadi pada satu atau kedua sisi rahang. Posterior crossbite adalah maloklusi yang paling sering muncul pada masa gigi susu dan awal gigi bercampur. Tujuan Perawatan: mengoreksi crossbite posterior dan mengembalikan fungsi pengunyahan yang baik. Kasus: Perempuan 20 tahun dengan maloklusi Angle klas III disertai crossbite posterior kanan, crowding rahang atas dan bawah. Penanganan: menggunakan alat cekat teknik Begg dengan pencabutan gigi premolar I rahang atas kiri, kedua premolar I rahang bawah, cross elastik, toe-in, dan toe out digunakan untuk koreksi crossbite. Kesimpulan: Perawatan crossbite posterior dengan teknik Begg menunjukkan hasil yang cukup memuaskan. Prognatik mandibula berkurang, crossbite terkoreksi, overjet normal, overbite normal, dan fungsi pengunyahan menjadi lebih baik.   Background: Posterior crossbite is defined as any abnormal bucal-lingual relations between posterior teeth of upper and lower jaw in centric occlusion which can occur in one side only or both. Posterior crossbite is one of the most prevalent malocclusion in primary and early mixed dentition. Purpose: to correct posterior and restore normal mastication. Case: 20 years old woman with Angle’s class II accompanied by posterior crossbite on the right side and crowding in anterior segment of upper and lower jaw. Management: using the Begg fixed appliance techniques with the extraction of upper left, and two lower first premolars. Cross elastic along with toe in and toe out on the main wire was used to correct posterior crossbite. Conclusion: Posterior crossbite treatment with Begg technique showed satisfactory results. Prognatism mandibula had reduced, regained normal overjet and overbite, and restored good mastication.

  15. Two years later - Revisiting autobiographical memory representations in vmPFC and hippocampus.

    Science.gov (United States)

    Bonnici, Heidi M; Maguire, Eleanor A

    2018-02-01

    A long-standing question in memory neuroscience concerns how and where autobiographical memories of personal experiences are represented in the brain. In a previous high resolution multivoxel pattern analysis fMRI study, we examined two week old (recent) and ten year old (remote) autobiographical memories (Bonnici et al., 2012, J. Neurosci. 32:16982-16991). We found that remote memories were particularly well represented in ventromedial prefrontal cortex (vmPFC) compared to recent memories. Moreover, while both types of memory were represented within anterior and posterior hippocampus, remote memories were more easily distinguished in the posterior portion. These findings suggested that a change of some kind had occurred between two weeks and ten years in terms of where autobiographical memories were represented in the brain. In order to examine this further, here participants from the original study returned two years later and recalled the memories again. We found that there was no difference in the detectability of memory representations within vmPFC for the now 2 year old and 12 year old memories, and this was also the case for the posterior hippocampus. Direct comparison of the two week old memories (original study) with themselves two years later (present study) confirmed that their representation within vmPFC had become more evident. Overall, this within-subjects longitudinal fMRI study extends our understanding of autobiographical memory representations by allowing us to narrow the window within which their consolidation is likely to occur. We conclude that after a memory is initially encoded, its representation within vmPFC has stablised by, at most, two years later. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Altered Effective Connectivity of Hippocampus-Dependent Episodic Memory Network in mTBI Survivors

    Directory of Open Access Journals (Sweden)

    Hao Yan

    2016-01-01

    Full Text Available Traumatic brain injuries (TBIs are generally recognized to affect episodic memory. However, less is known regarding how external force altered the way functionally connected brain structures of the episodic memory system interact. To address this issue, we adopted an effective connectivity based analysis, namely, multivariate Granger causality approach, to explore causal interactions within the brain network of interest. Results presented that TBI induced increased bilateral and decreased ipsilateral effective connectivity in the episodic memory network in comparison with that of normal controls. Moreover, the left anterior superior temporal gyrus (aSTG, the concept forming hub, left hippocampus (the personal experience binding hub, and left parahippocampal gyrus (the contextual association hub were no longer network hubs in TBI survivors, who compensated for hippocampal deficits by relying more on the right hippocampus (underlying perceptual memory and the right medial frontal gyrus (MeFG in the anterior prefrontal cortex (PFC. We postulated that the overrecruitment of the right anterior PFC caused dysfunction of the strategic component of episodic memory, which caused deteriorating episodic memory in mTBI survivors. Our findings also suggested that the pattern of brain network changes in TBI survivors presented similar functional consequences to normal aging.

  17. Rethinking "posterior" tongue-tie.

    Science.gov (United States)

    Douglas, Pamela Sylvia

    2013-12-01

    Currently, many clinicians who help with breastfeeding problems are diagnosing "posterior" tongue-tie in infants and performing or referring for frenotomy. In this "Speaking Out" article, I argue that the diagnosis of "posterior" tongue-tie has successfully raised awareness of the importance of impaired tongue function in breastfeeding difficulty. However, the diagnosis of "posterior" tongue-tie also applies a reductionist, medicalized theoretical frame to the complex problem of impaired tongue function, risking unintended outcomes. Impaired tongue function arises out of multiple interacting and co-evolving factors, including the interplay between social behaviors concerning breastfeeding and mother-infant biology. Consideration of theoretical frames is vital if we are to build an evidence base through efficient use of the scarce resources available for clinical breastfeeding research and minimize unintended outcomes.

  18. Epidural hematomas of posterior fossa

    Directory of Open Access Journals (Sweden)

    Radulović Danilo

    2004-01-01

    Full Text Available Background. Posterior fossa epidural hematomas represent 7-14% of all traumatic intracranial epidural hematomas. They are most frequently encountered posttraumatic mass lesions in the posterior fossa. The aim of this study was to identify clinical features that could lead to the early diagnosis of posterior fossa epidural hematoma. Methods. Between 1980 and 2002, 28 patients with epidural hematoma of the posterior fossa were operated on at the Institute for Neurosurgery, Belgrade. Clinical course neuroradiological investigations, and the results of surgical treatment of the patients with posterior fossa epidural hematomas were analyzed retrospectively. Results. Almost two thirds of patients were younger than 16 years of age. In 20 cases injury was caused by a fall, in 6 cases by a traffic accident, and in 2 by the assault. Clinical course was subacute or chronic in two thirds of the patients. On the admission Glasgow Coma Scale was 7 or less in 9 injured, 8-14 in 14 injured, and 15 in 5 injured patients. Linear fracture of the occipital bone was radiographically evident in 19 patients, but was intraoperatively encountered in all the patients except for a 4-year old child. In 25 patients the diagnosis was established by computer assisted tomography (CAT and in 3 by vertebral angiography. All the patients were operated on via suboccipital craniotomy. Four injured patients who were preoperatively comatose were with lethal outcome. Postoperatively, 24 patients were with sufficient neurologic recovery. Conclusion. Posterior fossa epidural hematoma should be suspected in cases of occipital injury, consciousness disturbances, and occipital bone fracture. In such cases urgent CAT-scan is recommended. Early recognition early diagnosis, and prompt treatment are crucial for good neurological recovery after surgery.

  19. Anterior canal BPPV and apogeotropic posterior canal BPPV: two rare forms of vertical canalolithiasis

    OpenAIRE

    CALIFANO, L.; SALAFIA, F.; MAZZONE, S.; MELILLO, M.G.; CALIFANO, M.

    2014-01-01

    SUMMARY Posterior canal benign paroxysmal positional vertigo (BPPV) is the most frequent form of BPPV. It is characterized by a paroxysmal positioning nystagmus evoked through Dix-Hallpike and Semont positioning tests. Anterior canal BPPV (AC) is more rare than posterior canal BPPV; it presents a prevalent down beating positioning nystagmus, with a torsional component clockwise for the left canal, counterclockwise for the right canal. Due to the possible lack of the torsional component, it is...

  20. MRI Volumetry of Hippocampus and Amygdala in Normal Aging, Mild Cognitive Impairment and Alzheimer's Disease Subjects

    International Nuclear Information System (INIS)

    Suphaphong, S.; Tritanon, O.; Laothamatas, J.; Sungkarat, W.

    2012-01-01

    The Alzheimer's disease (AD) and mild cognitive impairment (MCI) can affect memory and daily living. Non- invasive diagnostic tools such as MRI can be useful to discriminate the patients from normal group.This study aims to compare the relative volumes of hippocampus and amygdala, to suggest the relative normal volumes, and to evaluate MRI automatic volumetry as a diagnostic tool. The MRI images of 130 subjects were retrospectively studied (Turbo field echo (TFE), acquired with a 3-Tesla Philips scanner). The image data were processed with Free Surfer (automatic segmentation and volumetry). The resultant volumes were corrected for brain size differences with intracranial volumes (ICV), and then analysed with SPSS (v. 17.0). There are differences of hippocampus and amygdala relative volumes between normal, MCI, and AD subjects at p < 0.001. The volume reductions of hippocampus in MCI and AD groups compared to normal group are about 8 % and 28 %, while those of amygdala are about 10 % and 34 %, respectively. The relative volumes of hippocampus (compared to ICV) in normal aging are 0.002617 ± 0.000278 (right) and 0.002553 ± 0.000257 (left), while those of amygdala are 0.001231 ± 0.000165 (right) and 0.001096 ± 0.000144 (left). There are no differences of relative volumes affected by gender in normal, MCI, and AD. There is a highly significant difference of relative volume affected by brain side in normal group (p < 0.001) but not in MCI (p = 0.119 and 0.077) and AD (p = 0.713 and 0.250), for hippocampus and amygdala, respectively. These results demonstrate that there are volume losses of hippocampus and amygdala in both diseases. Automatically measured hippocampus and amygdala volumes can be used as a measure indicating MCI and AD. The abnormal disturbance of volume affected by brain side may indicate the progression of both diseases. The hippocampus and amygdala volumes can be used as one of diagnostic tools to confirm the diagnosis of MCI or AD. The volume

  1. Stereotactic laser ablation of amygdala and hippocampus using a Leksell stereotactic frame.

    Science.gov (United States)

    Awad, Ahmed J; Nguyen, Ha S; Arocho-Quinones, Elsa; Doan, Ninh; Mueller, Wade; Lew, Sean M

    2018-04-01

    Approximately one-third of patients with epilepsy are resistant to medical therapy, particularly in those with mesial temporal lobe epilepsy. While there are several surgical modalities, efforts have been focused on developing safer and minimally invasive techniques. In this video, the authors present the case of a 45-year-old woman with a 2-year history of refractory left mesial temporal lobe epilepsy who underwent MRI-guided laser ablation of amygdala and hippocampus. There were no perioperative complications. The video can be found here: https://youtu.be/XFHt2jTdE_4 .

  2. Can FDG PET predict verbal specific memory decline after surgery for left temporal lobe epilepsy when MRI is normal?

    International Nuclear Information System (INIS)

    Sagona, J.A.; Rowe, C.C.; Thomas, D.; Dickinson-Rowe, K.L.

    2002-01-01

    Full text: Temporal lobectomy gives excellent control of seizures in over 80% of patients with temporal lobe epilepsy. The left temporal lobe, particularly the left hippocampus, is primarily responsible for verbal memory. In most patients, the hippocampus which lies in the medial temporal lobe is abnormal and can be removed without loss of memory function. However, removal of the left hippocampus when it appears normal on MRI, often causes a significant decline in verbal specific memory (VSM) function. This paper explores the significance of pre-operative FDG-PET asymmetry in temporal lobe metabolism in predicting the VSM outcome after left temporal lobectomy when MRI demonstrates a normal hippocampus. Fifteen patients between 1993 and 2000, underwent left temporal lobectomy including left hippocampal resection, Pre-operatively all patients underwent 1.5T MRI, FDG PET and neuropsychological assessment. Neuropsychological assessment was repeated post-operatively. The left hippocampus was normal on MRI in nine and demonstrated mild T2 signal change without atrophy in six. FDG PET demonstrated temporal lobe hypometabolism in 12 patients. Post-operatively, neuropsychological evaluation documented a decline in verbal specific memory function in six patients, three with normal MRI and three with mild T2 change. We found that all patients with normal FDG PET studies (n=3) demonstrated significant verbal memory deterioration post-operatively. Nine of twelve patients (75%) with left temporal lobe hypometabolism did not show new verbal memory deficits. FDG PET improves the risk stratification for verbal specific memory decline with left temporal lobectomy in patients with normal hippocampi on MRI. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

  3. A New Variant of Posterior Canal Benign Paroxysmal Positional Vertigo: A Nonampullary or Common Crus Canalolithiasis

    Directory of Open Access Journals (Sweden)

    Sertac Yetiser

    2015-01-01

    Full Text Available Clockwise or counterclockwise, rotational, upbeating nystagmus is seen in patients with posterior canal benign paroxysmal positional vertigo during left or right head-hanging test, respectively. Rotating of nystagmus in opposite direction to the ear tested or even reversal of initial positioning rotational nystagmus is not usual and has never been reported before. We propose a new variant of posterior canal benign paroxysmal positional vertigo due to unusual behavior and location of the otoliths inside the membranous labyrinth. Unexpected rotational direction may lead to confusion about the site. The examiner should be aware of this abnormal or atypical variant of posterior canal benign paroxysmal positional vertigo.

  4. Posterior fossa meningioma (surgical experiences)

    African Journals Online (AJOL)

    Wael M. Moussa

    2012-08-27

    Aug 27, 2012 ... Abstract Introduction: Meningioma is a common tumor that represents about 30% of all intra- cranial tumors. Posterior fossa ... All patients had preoperative complete general and neurological examination, MRI of the brain with and without ..... in post-radiation nasopharyngeal carcinoma. Eur Radiol. 2009 ...

  5. Increased CSF-BACE1 activity associated with decreased hippocampus volume in Alzheimer's disease.

    LENUS (Irish Health Repository)

    Ewers, Michael

    2012-02-01

    The enzyme beta-secretase (BACE1) is essentially involved in the production of cerebral amyloidogenic pathology in Alzheimer\\'s disease (AD). The measurement of BACE1 activity in cerebrospinal fluid (CSF) has been reported, which may render CSF measurement of BACE1 a potential biomarker candidate of AD. In order to investigate whether BACE1 protein activity is correlated with regional brain atrophy in AD, we investigated the association between CSF levels of BACE1 and MRI-assessed hippocampus volume in patients with AD (n = 30). An increase in CSF-BACE1 activity was associated with decreased left and right hippocampus volume corrected for global head volume in the AD patients. Boot-strapped regression analysis showed that increased CSF levels of BACE1 activity were associated with increased CSF concentration of total tau but not amyloid-beta1-42 in AD. White matter hyperintensities did not influence the results. BACE1 activity and protein levels were significantly increased in AD compared to 19 elderly healthy controls. Thus, the CSF biomarker candidate of BACE1 activity was associated with hippocampus atrophy in AD in a robust manner and may reflect neurotoxic amyloid-beta-related processes.

  6. Object location memory impairment in patients with thermal lesions to the right or left hippocampus

    Czech Academy of Sciences Publication Activity Database

    Štěpánková, K.; Fenton, André Antonio; Pašťálková, Eva; Kalina, M.; Bohbot, V. D.

    2004-01-01

    Roč. 42, č. 8 (2004), s. 1017-1028 ISSN 0028-3932 R&D Projects: GA ČR GA309/02/1218 Grant - others:McDonnell Foundation(US) 97-34EE; McDonnell Foundation(US) 98-38 CNS-QUA.05; GA-(CA) NSERC Institutional research plan: CEZ:AV0Z5011922 Keywords : medial temporal lobe * location error * stereotaxic thermolesions Subject RIV: ED - Physiology Impact factor: 3.668, year: 2004

  7. Demonstration of decreased posterior cingulate perfusion in mild Alzheimer's disease by means of H215O positron emission tomography

    International Nuclear Information System (INIS)

    Ishii, Kazunari; Sasaki, Masahiro; Yamaji, Shigeru; Sakamoto, Setsu; Kitagaki, Hajime; Mori, Etsuro

    1997-01-01

    Although decreased posterior cingulate metabolism in Alzheimer's disease (AD) has been previously reported, there have been no reports on posterior cingulate perfusion. In this study we evaluated posterior cingulate perfusion as a relative value using statistical parametric maps (SPMs) and as an absolute value using conventional region of interest (ROI) settings. Twenty-eight subjects, including 14 patients with mild AD (mean age: 66.4±12.1 years) and 14 normal controls (65.9±7.3 years) were studied. Regional cerebral blood flow (CBF) was measured with H 2 15 O and positron emission tomography (PET). In the SPM analysis, the left posterior cingulate and left parietotemporal CBFs were significantly decreased in the patients with mild AD (P<0.001). At a lower statistical threshold (P<0.05), the right posterior cingulate and right parietotemporal CBFs were also significantly decreased in the AD patients. In the ROI studies, the left parietal and posterior cingulate CBFs in the patients with mild AD were significantly lower than those of the normal controls by analysis of variance and post-hoc Scheffe's test (P<0.001). We conclude that posterior cingulate perfusion is decreased in mild AD, reflecting the pathological changes and metabolic reduction in the posterior cingulate gyrus that have previously been reported to occur in mild AD. (orig.). With 1 fig., 2 tabs

  8. Circadian Oscillations within the Hippocampus Support Hippocampus-dependent Memory Processing

    Directory of Open Access Journals (Sweden)

    Kristin Lynn Eckel-Mahan

    2012-04-01

    Full Text Available The ability to sustain memories over long periods of time, sometimes even a lifetime, is one of the most remarkable properties of the brain. Much knowledge has been gained over the past few decades regarding the molecular correlates of memory formation. Once a memory is forged, however, the molecular events that provide permanence are as of yet unclear. Studies in multiple organisms have revealed that circadian rhythmicity is important for the formation, stability, and recall of memories [1]. The neuronal events that provide this link need to be explored further. This article will discuss the findings related to the circadian regulation of memory-dependent processes in the hippocampus. Specifically, the circadian-controlled MAP kinase and cAMP signal transduction pathway plays critical roles in the consolidation of hippocampus-dependent memory. A series of studies have revealed the circadian oscillation of this pathway within the hippocampus, an activity that is absent in memory-deficient, transgenic mice lacking Ca2+-stimulated adenylyl cyclases. Interference with these oscillations proceeding the cellular memory consolidation period impairs the persistence of hippocampus-dependent memory. These data suggest that the persistence of long-term memories may depend upon reactivation of this signal transduction pathway in the hippocampus during the circadian cycle. New data reveals the dependence of hippocampal oscillation in MAPK activity on the SCN, again underscoring the importance of this region in maintaining the circadian physiology of memory. Finally, the downstream ramification of these oscillations in terms of gene expression and epigenetics should be considered, as emerging evidence is pointing strongly to a circadian link between epigenetics and long term synaptic plasticity.

  9. Left atrial volume index

    DEFF Research Database (Denmark)

    Poulsen, Mikael K; Dahl, Jordi S; Henriksen, Jan Erik

    2013-01-01

    To determine the prognostic importance of left atrial (LA) dilatation in patients with type 2 diabetes (T2DM) and no history of cardiovascular disease.......To determine the prognostic importance of left atrial (LA) dilatation in patients with type 2 diabetes (T2DM) and no history of cardiovascular disease....

  10. Biomechanical Analysis of Stability of Posterior Antiglide Plating in Osteoporotic Pronation Abduction Ankle Fracture Model With Posterior Tibial Fragment.

    Science.gov (United States)

    Hartwich, Kathleen; Lorente Gomez, Alejandro; Pyrc, Jaroslaw; Gut, Radosław; Rammelt, Stefan; Grass, René

    2017-01-01

    We performed a biomechanical comparison of 2 methods for operative stabilization of pronation-abduction stage III ankle fractures; group 1: Anterior-posterior lag screws fixing the posterior tibial fragment and lateral fibula plating (LSLFP) versus group 2: locked plate fixation of the posterior tibial fragment and posterior antiglide plate fixation of the fibula (LPFP). Seven pairs of fresh-frozen osteoligamentous lower leg specimens (2 male, and 5 female donors) were used for the biomechanical testing. Bone mineral density (BMD) of each specimen was assessed by means of dual-energy x-ray absorptiometry. After open transection of the deltoid ligament, an osteotomy model of pronation abduction stage III ankle fracture was created. Specimens were systematically assigned to LSLFP (group 1, left ankles) or LPPFP (group 2, right ankles). After surgery, all specimens were evaluated via CT to verify reduction and fixation. Axial load was then applied onto each specimen using a servohydraulic testing machine starting from 0 N (Zwick/Roell, Ulm, Germany) at a speed of 10 N/s with the foot fixed in a 10 degrees pronation and 15 degrees dorsiflexion position. Construct stiffness, yield, and ultimate strength were measured and dislocation patterns were documented with a high-speed camera. The normal distribution of all data was analyzed using Shapiro-Wilk test. The group comparison was performed using paired Student t test. Statistical significance was assumed at a P value of .05. All specimens had BMD values consistent with osteoporosis. BMD values did not differ between the left and right ankles of the same pair ( P = .762). The mean BMD values between feet of men (0.603 g/cm 2 ) and women (0.329 g/cm 2 ) were statistically different ( P = .005). The ultimate strength for LSLFP (group 1) with 1139 ± 669 N and LPPFP (group 2) with 2008 ± 943 N was statistically different ( P = .036) as well as the yield in LSLFP (group 1) 812 ± 452 N and LPPFD (group 2) 1292 ± 625 N ( P

  11. Word and face recognition deficits following posterior cerebral artery stroke

    DEFF Research Database (Denmark)

    Kuhn, Christina D.; Asperud Thomsen, Johanne; Delfi, Tzvetelina

    2016-01-01

    Abstract Recent findings have challenged the existence of category specific brain areas for perceptual processing of words and faces, suggesting the existence of a common network supporting the recognition of both. We examined the performance of patients with focal lesions in posterior cortical...... areas to investigate whether deficits in recognition of words and faces systematically co-occur as would be expected if both functions rely on a common cerebral network. Seven right-handed patients with unilateral brain damage following stroke in areas supplied by the posterior cerebral artery were...... included (four with right hemisphere damage, three with left, tested at least 1 year post stroke). We examined word and face recognition using a delayed match-to-sample paradigm using four different categories of stimuli: cropped faces, full faces, words, and cars. Reading speed and word length effects...

  12. Visual Attention in Posterior Stroke and Relations to Alexia

    DEFF Research Database (Denmark)

    Petersen, Anders; Vangkilde, Signe; Fabricius, Charlotte

    2016-01-01

    that reduced visual speed and span may explain pure alexia. Eight patients with unilateral PCA strokes (four left hemisphere, four right hemisphere) were selected on the basis of lesion location, rather than the presence of any visual symptoms. Visual attention was characterized by a whole report paradigm......Impaired visual attention is common following strokes in the territory of the middle cerebral artery, particularly in the right hemisphere, while attentional effects of more posterior lesions are less clear. Commonly, such deficits are investigated in relation to specific syndromes like visual...... agnosia or pure alexia. The aim of this study was to characterize visual processing speed and apprehension span following posterior cerebral artery (PCA) stroke. In addition, the relationship between these attentional parameters and single word reading is investigated, as previous studies have suggested...

  13. Classification of posterior vitreous detachment

    OpenAIRE

    Kakehashi, Akihiro; Takezawa, Mikiko; Akiba, Jun

    2013-01-01

    Akihiro Kakehashi,1 Mikiko Takezawa,1 Jun Akiba21Department of Ophthalmology, Jichi Medical University, Saitama Medical Center, Saitama, 2Kanjodori Eye Clinic, Asahikawa, JapanAbstract: Diagnosing a posterior vitreous detachment (PVD) is important for predicting the prognosis and determining the indication for vitreoretinal surgery in many vitreoretinal diseases. This article presents both classifications of a PVD by slit-lamp biomicroscopy and of a shallow PVD by optical coherence tomography...

  14. Posterior reversible encephalopathy syndrome in the emergency ...

    African Journals Online (AJOL)

    Posterior reversible encephalopathy syndrome in the emergency service. ... The most common etiologies of PRES are hypertension and renal failure, and the most frequent pathophysiology is hyperperfusion. PRES is ... Keywords: Emergency service, hyperperfusion, posterior reversible encephalopathy, vasogenic edema ...

  15. Association between income and the hippocampus.

    Directory of Open Access Journals (Sweden)

    Jamie L Hanson

    2011-05-01

    Full Text Available Facets of the post-natal environment including the type and complexity of environmental stimuli, the quality of parenting behaviors, and the amount and type of stress experienced by a child affects brain and behavioral functioning. Poverty is a type of pervasive experience that is likely to influence biobehavioral processes because children developing in such environments often encounter high levels of stress and reduced environmental stimulation. This study explores the association between socioeconomic status and the hippocampus, a brain region involved in learning and memory that is known to be affected by stress. We employ a voxel-based morphometry analytic framework with region of interest drawing for structural brain images acquired from participants across the socioeconomic spectrum (n = 317. Children from lower income backgrounds had lower hippocampal gray matter density, a measure of volume. This finding is discussed in terms of disparities in education and health that are observed across the socioeconomic spectrum.

  16. The Hippocampus Remains Activated over the Long Term for the Retrieval of Truly Episodic Memories

    Science.gov (United States)

    Harand, Caroline; Bertran, Françoise; La Joie, Renaud; Landeau, Brigitte; Mézenge, Florence; Desgranges, Béatrice; Peigneux, Philippe; Eustache, Francis; Rauchs, Géraldine

    2012-01-01

    The role of the hippocampus in declarative memory consolidation is a matter of intense debate. We investigated the neural substrates of memory retrieval for recent and remote information using functional magnetic resonance imaging (fMRI). 18 young, healthy participants learned a series of pictures. Then, during two fMRI recognition sessions, 3 days and 3 months later, they had to determine whether they recognized or not each picture using the “Remember/Know” procedure. Presentation of the same learned images at both delays allowed us to track the evolution of memories and distinguish consistently episodic memories from those that were initially episodic and then became familiar or semantic over time and were retrieved without any contextual detail. Hippocampal activation decreased over time for initially episodic, later semantic memories, but remained stable for consistently episodic ones, at least in its posterior part. For both types of memories, neocortical activations were observed at both delays, notably in the ventromedial prefrontal and anterior cingulate cortices. These activations may reflect a gradual reorganization of memory traces within neural networks. Our data indicate maintenance and strengthening of hippocampal and cortico-cortical connections in the consolidation and retrieval of episodic memories over time, in line with the Multiple Trace theory (Nadel and Moscovitch, 1997). At variance, memories becoming semantic over time consolidate through strengthening of cortico-cortical connections and progressive disengagement of the hippocampus. PMID:22937055

  17. Left heart catheterization

    Science.gov (United States)

    Catheterization - left heart ... to help guide the catheters up into your heart and arteries. Dye (sometimes called "contrast") will be ... in the blood vessels that lead to your heart. The catheter is then moved through the aortic ...

  18. Cardiac pacing in heart failure patients with left bundle branch block: impact of pacing site for optimizing left ventricular resynchronization.

    Science.gov (United States)

    Pappone, C; Rosanio, S; Oreto, G; Tocchi, M; Gulletta, S; Salvati, A; Dicandia, C; Santinelli, V; Mazzone, P; Veglia, F; Ding, J; Sallusti, L; Spinelli, J; Vicedomini, G

    2000-07-01

    Acute left ventricular pacing has been associated with hemodynamic improvement in patients with congestive heart failure and wide QRS complex. We hypothesized that pacing two left ventricular sites simultaneously would produce faster activation and better systolic function than single-site pacing. We selected 14 heart failure patients (NYHA functional class III or IV) in normal sinus rhythm with left bundle branch block and QRS > 150 ms. An 8F dual micromanometer catheter was placed in the aorta for measuring +dP/dt (mmHg/s), aortic pulse pressure (mmHg), and end-diastolic pressure (mmHg). Pacing leads were positioned via coronary veins at the posterior base and lateral wall. Patients were acutely paced VDD at the posterior base, lateral wall, and both sites (dual-site) with 5 atrioventricular delays (from 8 ms to PR -30 ms). Pacing sequences were executed in randomized order using a custom external computer (FlexStim, Guidant CRM). Dual-site pacing increased peak +dP/dt significantly more than posterior base and lateral wall pacing. Dual-site and posterior base pacing raised aortic pulse pressure significantly more than lateral wall pacing. Dual-site pacing shortened QRS duration by 22 %, whereas posterior base and lateral wall pacing increased it by 2 and 12%, respectively (p = 0.006). In heart failure patients with left bundle branch block, dual-site pacing improves systolic function more than single-site stimulation. Improved ventricular activation synchrony, expressed by paced QRS narrowing, may account for the additional benefit of dual- vs single-site pacing in enhancing contractility. This novel approach deserves consideration for future heart failure pacing studies.

  19. Noninvasive and Transient Blood-Brain Barrier Opening in the Hippocampus of Alzheimer's Double Transgenic Mice Using Focused Ultrasound

    Science.gov (United States)

    Choi, James J.; Wang, Shougang; Brown, Truman R.; Small, Scott A.; Duff, Karen E. K.; Konofagou, Elisa E.

    2009-01-01

    The spatio-temporal nature of focused ultrasound-induced blood-brain barrier (BBB) opening as a brain drug delivery method was investigated in Alzheimer's disease model mice. The left hippocampus of transgenic (APP/PS1, n = 3) and nontransgenic (n = 3) mice was sonicated (frequency: 1.525 MHz, peak-negative pressure: 600 kPa, pulse length: 20 ms, duty cycle: 20%, duration: 1 min) in vivo, through their intact skin and skull, after intravenous injection of microbubbles (SonoVue®; 25 μl). Sequential, high-field MR images (9.4 Tesla) were acquired before and after injection of gadolinium (Omniscan™; 0.75 ml, molecular weight: 573.7 Da) on two separate days for each mouse. Gadolinium deposits through the ultrasound-induced BBB opening in the left hippocampus revealed significant contrast-enhancement in the MRI. On the following day, MRI revealed significant BBB closure within the same region. However, the BBB opening extent and BBB closing timeline varied in different regions within the same sonicated location. This indicates that opening and closing were dependent on the brain region targeted. No significant difference in BBB opening or closing behaviors was observed between the APP/PS1 and the nontransgenic mice. In conclusion, a BBB-impermeable molecule was noninvasively, transiently and reproducibly delivered to the hippocampus of Alzheimer's APP/PS1 mice. PMID:19149463

  20. Huge interparietal posterior fontanel meningohydroencephalocele

    OpenAIRE

    Jorge Félix Companioni Rosildo; Manuel Filipe Dias dos Santos; Rita de Cassia de Santa Barbara

    2015-01-01

    Congenital encephalocele is a neural tube defect characterized by a sac-like protrusion of the brain, meninges, and other intracranial structures through the skull, which is caused by an embryonic development abnormality. The most common location is at the occipital bone, and its incidence varies according to different world regions. We report a case of an 1-month and 7-day-old male child with a huge interparietal-posterior fontanel meningohydroencephalocele, a rare occurrence. Physical exami...

  1. Nipro extra-corporeal left ventricular assist device fitting after left ventricular reconstruction with mitral valve plasty.

    Science.gov (United States)

    Arakawa, Mamoru; Yamaguchi, Atsushi; Nishimura, Takashi; Itoh, Satoshi; Yuri, Koichi; Kyo, Shunei; Adachi, Hideo

    2015-12-01

    Both left ventricular assist device and left ventricular reconstruction are treatment choices for severe heart failure conditions. Our institution performed a left ventricular assist device installation following a left ventricular reconstruction procedure on a 42-year-old male patient who presented with dilated cardiomyopathy and low cardiac output syndrome. A mitral valve plasty was used to correct the acute mitral valve regurgitation and we performed a Nipro extra-corporeal left ventricular assist device installation on post-operative day 14. Due to the left ventricular reconstruction that the patient had in a previous operation, we needed to attach an apical cuff on posterior apex, insert the inflow cannula with a large curve, and shift the skin insertion site laterally to the left. We assessed the angle between the cardiac longitudinal axis and the inflow cannula using computed tomography. The patient did not complain of any subjective symptoms of heart failure. Although Nipro extra-corporeal left ventricular assist device installation after left ventricular reconstruction has several difficulties historically, we have experienced a successful case.

  2. Role of the hippocampus in memory functioning: modern view

    Directory of Open Access Journals (Sweden)

    D. O. Assonov

    2017-12-01

    Full Text Available The purpose of this review was to develop the comprehensive conception of the hippocampus role in the functioning of human memory, based on data obtained by analysis of the latest scientific literature on the topic and make recommendations for further ways of researches in this topic. The scientific literature of the last 5 years on the role of the hippocampus in memory functioning was analyzed. Based on the reviewed literature, we made the next conclusions: the hippocampus is an extremely important for memory structure with various connections for different types of memory; the hippocampus is affected by a variety of substances, most studied now are glucocorticosteroids, whose effect on memory differs depending on the start time of action; the hippocampus volume in mental disorders affecting memory is less than normal, which makes it an important diagnostic criterion; at the moment, various promising methods that can help in the therapy of PTSD, depression, phobias and other disorders associated with memory impairment and based on the knowledge of the hippocampus for the treatment of memory disorders are being developed. Based on these conclusions and data, which were analyzed, we offered the following recommendations: to implement the hippocampal function examination in the diagnostics of mental disorders, which are accompanied by a violation of its work; to use the size of the hippocampus as one of the prognostic factors for the severity of the memory-associated disorders and the therapy progress; to carefully investigate the difference in the effect of various psychotherapies and pharmacotherapies on the hippocampus to determine exactly which of the therapies is the most morphologically reasonable; to find out how significant the decrease in the hippocampal volume is for the memory functioning; to use pathogenetically and morphologically based methods to improve the function of the hippocampus in the treatment of disorders that are

  3. Alveolar ridge expansion-assisted orthodontic space closure in the mandibular posterior region.

    Science.gov (United States)

    Ozer, Mete; Akdeniz, Berat Serdar; Sumer, Mahmut

    2013-12-01

    Orthodontic closure of old, edentulous spaces in the mandibular posterior region is a major challenge. In this report, we describe a method of orthodontic closure of edentulous spaces in the mandibular posterior region accelerated by piezoelectric decortication and alveolar ridge expansion. Combined piezosurgical and orthodontic treatments were used to close 14- and 15-mm-wide spaces in the mandibular left and right posterior areas, respectively, of a female patient, aged 18 years and 9 months, diagnosed with skeletal Class III malocclusion, hypodontia, and polydiastemas. After the piezoelectric decortication, segmental and full-arch mechanics were applied in the orthodontic phase. Despite some extent of root resorption and anchorage loss, the edentulous spaces were closed, and adequate function and esthetics were regained without further restorative treatment. Alveolar ridge expansion-assisted orthodontic space closure seems to be an effective and relatively less-invasive treatment alternative for edentulous spaces in the mandibular posterior region.

  4. Huge interparietal posterior fontanel meningohydroencephalocele

    Directory of Open Access Journals (Sweden)

    Jorge Félix Companioni Rosildo

    2015-03-01

    Full Text Available Congenital encephalocele is a neural tube defect characterized by a sac-like protrusion of the brain, meninges, and other intracranial structures through the skull, which is caused by an embryonic development abnormality. The most common location is at the occipital bone, and its incidence varies according to different world regions. We report a case of an 1-month and 7-day-old male child with a huge interparietal-posterior fontanel meningohydroencephalocele, a rare occurrence. Physical examination and volumetric computed tomography were diagnostic. The encephalocele was surgically resected. Intradural and extradural approaches were performed; the bone defect was not primarily closed. Two days after surgery, the patient developed hydrocephaly requiring ventriculoperitoneal shunting. The surgical treatment of the meningohydroencephalocele of the interparietal-posterior fontanel may be accompanied by technical challenges and followed by complications due to the presence of large blood vessels under the overlying skin. In these cases, huge sacs herniate through large bone defects including meninges, brain, and blood vessels. The latter present communication with the superior sagittal sinus and ventricular system. A favorable surgical outcome generally follows an accurate strategy taking into account individual features of the lesion.

  5. Intracranially protruded bilateral posterior and superior SCCs with multiple dehiscences in a patient with positional vertigo: CT and MR imaging findings and review of literature

    Directory of Open Access Journals (Sweden)

    Nischal G Kundaragi

    2014-01-01

    Full Text Available We report a rare case of intracranially protruded posterior and superior semicircular canals beyond the margins of temporal bone with bony roof dehiscence in bilateral posterior and left superior semicircular canals in a patient with benign paroxysmal positional vertigo (BPPV.

  6. Nystagmus discordance with 2-dimensional videonystagmography in posterior semicircular canal benign paroxysmal positional vertigo.

    Science.gov (United States)

    VanDerHeyden, Crystal M; Carender, Wendy J; Heidenreich, Katherine D

    2015-04-01

    The Dix-Hallpike test is a standard component of the videonystagmography test battery and can diagnose posterior semicircular canal benign paroxysmal positional vertigo. The purpose of this study is to determine the prevalence of discordant, equivocal, and concordant nystagmus tracings in active posterior semicircular canal benign paroxysmal positional vertigo when compared directly with the eye video. Case series with chart review of patients diagnosed with posterior semicircular canal benign paroxysmal positional vertigo by 2-dimensional videonystagmography from August 1, 2007, to August 1, 2012. A tertiary vestibular test laboratory. Ninety-six adults (4 had bilateral involvement) with posterior semicircular canal benign paroxysmal positional vertigo were included. A total of 100 videos with accompanying videonystagmography tracings were reviewed to determine nystagmus trajectory as well as globe position. Descriptive statistics were used to describe prevalence. Fisher exact test was used to compare proportions. Sixty-two percent of cases involved benign paroxysmal positional vertigo of the right posterior semicircular canal, while 38% involved the left posterior semicircular canal. The prevalence of discordant, equivocal, and concordant tracings was 65% (65/100), 29% (29/100), and 6% (6/100). All tracing errors involved the horizontal channel. There was no association between tracing accuracy and the ear of involvement or globe position (P > .05). Two-dimensional videonystagmography tracings are not reliable for identifying nystagmus trajectory in posterior semicircular canal benign paroxysmal positional vertigo. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.

  7. [Recurrent left atrial myxoma].

    Science.gov (United States)

    Moreno Martínez, Francisco L; Lagomasino Hidalgo, Alvaro; Mirabal Rodríguez, Roger; López Bermúdez, Félix H; López Bernal, Omaida J

    2003-01-01

    Primary cardiac tumors are rare. Mixomas are the most common among them; 75% are located in the left atrium, 20% in the right atrium, and the rest in the ventricles. The seldom appear in atrio-ventricular valves. Recidivant mixoma are also rare, appearing in 1-5% of all patients that have undergone surgical treatment of a mixoma. In this paper we present our experience with a female patient, who 8 years after having been operated of a left atrial mixoma, began with symptoms of mild heart failure. Transthoracic echocardiography revealed recurrence of the tumor, and was therefore subjected to a second open-heart surgery from which she recovered without complications.

  8. Hippocampus and amygdala morphology in attention-deficit/hyperactivity disorder

    DEFF Research Database (Denmark)

    Plessen, Kerstin J; Bansal, Ravi; Zhu, Hongtu

    2006-01-01

    CONTEXT: Limbic structures are implicated in the genesis of attention-deficit/hyperactivity disorder (ADHD) by the presence of mood and cognitive disturbances in affected individuals and by elevated rates of mood disorders in family members of probands with ADHD. OBJECTIVE: To study the morphology...... of the hippocampus and amygdala in children with ADHD. DESIGN: A cross-sectional case-control study of the hippocampus and amygdala using anatomical magnetic resonance imaging. SETTINGS: University research institute. PATIENTS: One hundred fourteen individuals aged 6 to 18 years, 51 with combined-type ADHD and 63...... healthy controls. MAIN OUTCOME MEASURES: Volumes and measures of surface morphology for the hippocampus and amygdala. RESULTS: The hippocampus was larger bilaterally in the ADHD group than in the control group (t = 3.35; P

  9. Somatostatin receptors in rat hippocampus: localization to intrinsic neurons

    International Nuclear Information System (INIS)

    Palacios, J.M.; Reubi, J.C.; Maurer, R.

    1986-01-01

    The effect of neurotoxic chemical and electrolytical lesions on somatostatin (SS) receptor binding in the septo-hippocampal afferents, pyramidal and granule cells of the rat hippocampus was examined by autoradiography using the stable SS analogue 125 I-204-090 as radioligand. Electrolytical lesions of the septum did not result in modification of SS binding in the hippocampus. In contrast, both granule cell lesion with colchicine and pyramidal or pyramidal and granule cell lesions with increasing kainic acid doses did result in a specific decrease of binding in the dentate gyrus and hippocampus (CA 1 and CA 3 ). These results suggest that SS receptors in the hippocampus are probably associated with elements from intrinsic neurons. (Author)

  10. The hippocampus: hub of brain network communication for memory.

    NARCIS (Netherlands)

    Battaglia, F.P.; Benchenane, K.; Sirota, A.; Pennartz, C.M.A.; Wiener, S.I.

    2011-01-01

    A complex brain network, centered on the hippocampus, supports episodic memories throughout their lifetimes. Classically, upon memory encoding during active behavior, hippocampal activity is dominated by theta oscillations (6-10Hz). During inactivity, hippocampal neurons burst synchronously,

  11. Left atrial appendage occlusion

    Directory of Open Access Journals (Sweden)

    Ahmad Mirdamadi

    2013-01-01

    Full Text Available Left atrial appendage (LAA occlusion is a treatment strategy to prevent blood clot formation in atrial appendage. Although, LAA occlusion usually was done by catheter-based techniques, especially percutaneous trans-luminal mitral commissurotomy (PTMC, it can be done during closed and open mitral valve commissurotomy (CMVC, OMVC and mitral valve replacement (MVR too. Nowadays, PTMC is performed as an optimal management of severe mitral stenosis (MS and many patients currently are treated by PTMC instead of previous surgical methods. One of the most important contraindications of PTMC is presence of clot in LAA. So, each patient who suffers of severe MS is evaluated by Trans-Esophageal Echocardiogram to rule out thrombus in LAA before PTMC. At open heart surgery, replacement of the mitral valve was performed for 49-year-old woman. Also, left atrial appendage occlusion was done during surgery. Immediately after surgery, echocardiography demonstrates an echo imitated the presence of a thrombus in left atrial appendage area, although there was not any evidence of thrombus in pre-pump TEE. We can conclude from this case report that when we suspect of thrombus of left atrial, we should obtain exact history of previous surgery of mitral valve to avoid misdiagnosis clotted LAA, instead of obliterated LAA. Consequently, it can prevent additional evaluations and treatments such as oral anticoagulation and exclusion or postponing surgeries including PTMC.

  12. FRACTURE DISLOCATION OF LEFT SHOULDER: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Mazharuddin Ali

    2015-05-01

    Full Text Available Many systemic disorders present with orthopedic manifestations. A 40 year old male patient was brought in with pain and inability to move his left arm after he regained consciousness. The patient is a known case of Epilepsy since 2 years and had two episodes of seizure like activity and not on any medication. The diagnosis was fracture posterior dislocation of left shoulder following Grand mal Epilepsy. It was a 3 part fracture dislocation of left shoulder emergency closed reduction and 5 percutaneous K wires fixation was done under general anaesthe sia and universal shoulder immobilizer was applied to immobilize the left shoulder in flexion, adduction and internal rotation. Treatment for epilepsy was continued. After four weeks K wires were removed. With physiotherapy, patient regained full range of movements by 8 weeks. We conclude, that a fracture posterior dislocation of left shoulder as a presenting feature should arouse us to evaluate the cause, in our case it was convulsion. Closed reduction and internal fixation with percutaneous k - wires reduces infection rate and hospital stay. Patient recovered well without any complications

  13. Donor/recipient enhancement of memory in rat hippocampus

    OpenAIRE

    Deadwyler, Sam A.; Berger, Theodore W.; Sweatt, Andrew J.; Song, Dong; Chan, Rosa H. M.; Opris, Ioan; Gerhardt, Greg A.; Marmarelis, Vasilis Z.; Hampson, Robert E.

    2013-01-01

    The critical role of the mammalian hippocampus in the formation, translation and retrieval of memory has been documented over many decades. There are many theories of how the hippocampus operates to encode events and a precise mechanism was recently identified in rats performing a short-term memory task which demonstrated that successful information encoding was promoted via specific patterns of activity generated within ensembles of hippocampal neurons. In the study presented here these ‘rep...

  14. Hippocampus, delay discounting, and vicarious trial-and-error.

    Science.gov (United States)

    Bett, David; Murdoch, Lauren H; Wood, Emma R; Dudchenko, Paul A

    2015-05-01

    In decision-making, an immediate reward is usually preferred to a delayed reward, even if the latter is larger. We tested whether the hippocampus is necessary for this form of temporal discounting, and for vicarious trial-and-error at the decision point. Rats were trained on a recently developed, adjustable delay-discounting task (Papale et al. (2012) Cogn Affect Behav Neurosci 12:513-526), which featured a choice between a small, nearly immediate reward, and a larger, delayed reward. Rats then received either hippocampus or sham lesions. Animals with hippocampus lesions adjusted the delay for the larger reward to a level similar to that of sham-lesioned animals, suggesting a similar valuation capacity. However, the hippocampus lesion group spent significantly longer investigating the small and large rewards in the first part of the sessions, and were less sensitive to changes in the amount of reward in the large reward maze arm. Both sham- and hippocampus-lesioned rats showed a greater amount of vicarious trial-and-error on trials in which the delay was adjusted. In a nonadjusting version of the delay discounting task, animals with hippocampus lesions showed more variability in their preference for a larger reward that was delayed by 10 s compared with sham-lesioned animals. To verify the lesion behaviorally, rat were subsequently trained on a water maze task, and rats with hippocampus lesions were significantly impaired compared with sham-lesioned animals. The findings on the delay discounting tasks suggest that damage to the hippocampus may impair the detection of reward magnitude. © 2014 Wiley Periodicals, Inc.

  15. Posterior ankle impingement in the dancer.

    Science.gov (United States)

    Moser, Brad R

    2011-01-01

    Dancers spend a lot of time in the relevé position in demi-pointe and en pointe in their training and their careers. Pain from both osseous and soft tissue causes may start to occur in the posterior aspect of their ankle. This article reviews the potential causes of posterior ankle impingement in dancers. It will discuss the clinical evaluation of a dancer and the appropriate workup and radiographic studies needed to further evaluate a dancer with suspected posterior ankle impingement.

  16. Primary Left Cardiac Angiosarcoma with Mitral Valve Involvement Accompanying Coronary Artery Disease

    Directory of Open Access Journals (Sweden)

    Cagdas Baran

    2015-01-01

    Full Text Available We report here on a 43-year-old female patient presenting with non-ST elevation myocardial infarction, severe mitral regurgitation, and mild mitral stenosis secondary to encroachment of the related structures by a primary cardiac angiosarcoma. A coronary angiography revealed significant stenosis in the left main and left circumflex arteries and at exploration, the tumour was arising from posterior left atrial free wall, invading the posterior mitral leaflet, and extending into all of the pulmonary veins and pericardium. Therefore, no further intervention was performed, except for left internal mammarian artery to left anterior descending artery anastomosis and biopsy. As far as we know, this case is unique with respect to its presentation.

  17. Hypoplastic left heart syndrome

    Directory of Open Access Journals (Sweden)

    Thiagarajan Ravi

    2007-05-01

    Full Text Available Abstract Hypoplastic left heart syndrome(HLHS refers to the abnormal development of the left-sided cardiac structures, resulting in obstruction to blood flow from the left ventricular outflow tract. In addition, the syndrome includes underdevelopment of the left ventricle, aorta, and aortic arch, as well as mitral atresia or stenosis. HLHS has been reported to occur in approximately 0.016 to 0.036% of all live births. Newborn infants with the condition generally are born at full term and initially appear healthy. As the arterial duct closes, the systemic perfusion becomes decreased, resulting in hypoxemia, acidosis, and shock. Usually, no heart murmur, or a non-specific heart murmur, may be detected. The second heart sound is loud and single because of aortic atresia. Often the liver is enlarged secondary to congestive heart failure. The embryologic cause of the disease, as in the case of most congenital cardiac defects, is not fully known. The most useful diagnostic modality is the echocardiogram. The syndrome can be diagnosed by fetal echocardiography between 18 and 22 weeks of gestation. Differential diagnosis includes other left-sided obstructive lesions where the systemic circulation is dependent on ductal flow (critical aortic stenosis, coarctation of the aorta, interrupted aortic arch. Children with the syndrome require surgery as neonates, as they have duct-dependent systemic circulation. Currently, there are two major modalities, primary cardiac transplantation or a series of staged functionally univentricular palliations. The treatment chosen is dependent on the preference of the institution, its experience, and also preference. Although survival following initial surgical intervention has improved significantly over the last 20 years, significant mortality and morbidity are present for both surgical strategies. As a result pediatric cardiologists continue to be challenged by discussions with families regarding initial decision

  18. Visual neglect in posterior cortical atrophy

    Directory of Open Access Journals (Sweden)

    Andrade Katia

    2010-08-01

    Full Text Available Abstract Background In posterior cortical atrophy (PCA, there is a progressive impairment of high-level visual functions and parietal damage, which might predict the occurrence of visual neglect. However, neglect may pass undetected if not assessed with specific tests, and might therefore be underestimated in PCA. In this prospective study, we aimed at establishing the side, the frequency and the severity of visual neglect, visual extinction, and primary visual field defects in an unselected sample of PCA patients. Methods Twenty-four right-handed PCA patients underwent a standardized battery of neglect tests. Visual fields were examined clinically by the confrontation method. Results Sixteen of the 24 patients (66% had signs of visual neglect on at least one test, and fourteen (58% also had visual extinction or hemianopia. Five patients (21% had neither neglect nor visual field defects. As expected, left-sided neglect was more severe than right-sided neglect. However, right-sided neglect resulted more frequently in this population (29% than in previous studies on focal brain lesions. Conclusion When assessed with specific visuospatial tests, visual neglect is frequent in patients with PCA. Diagnosis of neglect is important because of its negative impact on daily activities. Clinicians should consider the routine use of neglect tests to screen patients with high-level visual deficits. The relatively high frequency of right-sided neglect in neurodegenerative patients supports the hypothesis that bilateral brain damage is necessary for right-sided neglect signs to occur, perhaps because of the presence in the right hemisphere of crucial structures whose damage contributes to neglect.

  19. Pterygoid implant for atrophic posterior maxilla

    Directory of Open Access Journals (Sweden)

    V R Balaji

    2017-01-01

    Full Text Available Replacement of missing teeth in the posterior maxilla is always a challenge for the treating implant surgeon as the posterior maxilla has several obstacles in the form of quality, quantity, the anatomy of the maxillary sinus, and inaccessibility. To overcome these deficiencies, several surgical procedures such as sinus lift, bone augmentation, tilted implants, short implants, and zygomatic implants were tried. Since these procedures have their own limitations, pterygomaxillary region provides us an excellent place for placement of implant and rehabilitation of posterior maxilla. This case report describes the usage of the pterygomaxillary region for placement of the implant to restore atrophic posterior maxilla, without any additional surgical procedures.

  20. Asynchronous ripple oscillations between left and right hippocampi during slow-wave sleep.

    Science.gov (United States)

    Villalobos, Claudio; Maldonado, Pedro E; Valdés, José L

    2017-01-01

    Spatial memory, among many other brain processes, shows hemispheric lateralization. Most of the published evidence suggests that the right hippocampus plays a leading role in the manipulation of spatial information. Concurrently in the hippocampus, memory consolidation during sleep periods is one of the key steps in the formation of newly acquired spatial memory traces. One of the most characteristic oscillatory patterns in the hippocampus are sharp-wave ripple (SWR) complexes. Within this complex, fast-field oscillations or ripples have been demonstrated to be instrumental in the memory consolidation process. Since these ripples are relevant for the consolidation of memory traces associated with spatial navigation, and this process appears to be lateralized, we hypothesize that ripple events between both hippocampi would exhibit different temporal dynamics. We tested this idea by using a modified "split-hyperdrive" that allows us to record simultaneous LFPs from both right and left hippocampi of Sprague-Dawley rats during sleep. We detected individual events and found that during sleep periods these ripples exhibited a different occurrence patterns between hemispheres. Most ripple events were synchronous between intra- rather than inter-hemispherical recordings, suggesting that ripples in the hippocampus are independently generated and locally propagated within a specific hemisphere. In this study, we propose the ripples' lack of synchrony between left and right hippocampi as the putative physiological mechanism underlying lateralization of spatial memory.

  1. Asynchronous ripple oscillations between left and right hippocampi during slow-wave sleep.

    Directory of Open Access Journals (Sweden)

    Claudio Villalobos

    Full Text Available Spatial memory, among many other brain processes, shows hemispheric lateralization. Most of the published evidence suggests that the right hippocampus plays a leading role in the manipulation of spatial information. Concurrently in the hippocampus, memory consolidation during sleep periods is one of the key steps in the formation of newly acquired spatial memory traces. One of the most characteristic oscillatory patterns in the hippocampus are sharp-wave ripple (SWR complexes. Within this complex, fast-field oscillations or ripples have been demonstrated to be instrumental in the memory consolidation process. Since these ripples are relevant for the consolidation of memory traces associated with spatial navigation, and this process appears to be lateralized, we hypothesize that ripple events between both hippocampi would exhibit different temporal dynamics. We tested this idea by using a modified "split-hyperdrive" that allows us to record simultaneous LFPs from both right and left hippocampi of Sprague-Dawley rats during sleep. We detected individual events and found that during sleep periods these ripples exhibited a different occurrence patterns between hemispheres. Most ripple events were synchronous between intra- rather than inter-hemispherical recordings, suggesting that ripples in the hippocampus are independently generated and locally propagated within a specific hemisphere. In this study, we propose the ripples' lack of synchrony between left and right hippocampi as the putative physiological mechanism underlying lateralization of spatial memory.

  2. The Neuroanatomical Basis for Posterior Superior Parietal Lobule Control Lateralization of Visuospatial Attention.

    Science.gov (United States)

    Wu, Yan; Wang, Jiaojian; Zhang, Yun; Zheng, Dingchen; Zhang, Jinfeng; Rong, Menglin; Wu, Huawang; Wang, Yinyan; Zhou, Ke; Jiang, Tianzi

    2016-01-01

    The right hemispheric dominance in visuospatial attention in human brain has been well established. Converging evidence has documented that ventral posterior parietal cortex (PPC) plays an important role in visuospatial attention. The role of dorsal PPC subregions, especially the superior parietal lobule (SPL) in visuospatial attention is still controversial. In the current study, we used repetitive transcranial magnetic stimulation (rTMS) and diffusion magnetic resonance imaging (MRI) techniques to test the role of posterior SPL in visuospatial attention and to investigate the potential neuroanatomical basis for right hemisphere dominance in visuospatial function. Transcranial magnetic stimulation (TMS) results unraveled that the right SPL predominantly mediated visuospatial attention compared to left SPL. Anatomical connections analyses between the posterior SPL and the intrahemispheric frontal subregions and the contralateral PPC revealed that right posterior SPL has stronger anatomical connections with the ipsilateral middle frontal gyrus (MFG), with the ipsilateral inferior frontal gyrus (IFG), and with contralateral PPC than that of the left posterior SPL. Furthermore, these asymmetric anatomical connections were closely related to behavioral performances. Our findings indicate that SPL plays a crucial role in regulating visuospatial attention, and dominance of visuospatial attention results from unbalanced interactions between the bilateral fronto-parietal networks and the interhemispheric parietal network.

  3. An interplay of fusiform gyrus and hippocampus enables prototype- and exemplar-based category learning.

    Science.gov (United States)

    Lech, Robert K; Güntürkün, Onur; Suchan, Boris

    2016-09-15

    The aim of the present study was to examine the contributions of different brain structures to prototype- and exemplar-based category learning using functional magnetic resonance imaging (fMRI). Twenty-eight subjects performed a categorization task in which they had to assign prototypes and exceptions to two different families. This test procedure usually produces different learning curves for prototype and exception stimuli. Our behavioral data replicated these previous findings by showing an initially superior performance for prototypes and typical stimuli and a switch from a prototype-based to an exemplar-based categorization for exceptions in the later learning phases. Since performance varied, we divided participants into learners and non-learners. Analysis of the functional imaging data revealed that the interaction of group (learners vs. non-learners) and block (Block 5 vs. Block 1) yielded an activation of the left fusiform gyrus for the processing of prototypes, and an activation of the right hippocampus for exceptions after learning the categories. Thus, successful prototype- and exemplar-based category learning is associated with activations of complementary neural substrates that constitute object-based processes of the ventral visual stream and their interaction with unique-cue representations, possibly based on sparse coding within the hippocampus. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Left Ventricular Assist Devices

    Directory of Open Access Journals (Sweden)

    Khuansiri Narajeenron

    2017-04-01

    Full Text Available Audience: The audience for this classic team-based learning (cTBL session is emergency medicine residents, faculty, and students; although this topic is applicable to internal medicine and family medicine residents. Introduction: A left ventricular assist device (LVAD is a mechanical circulatory support device that can be placed in critically-ill patients who have poor left ventricular function. After LVAD implantation, patients have improved quality of life.1 The number of LVAD patients worldwide continues to rise. Left-ventricular assist device patients may present to the emergency department (ED with severe, life-threatening conditions. It is essential that emergency physicians have a good understanding of LVADs and their complications. Objectives: Upon completion of this cTBL module, the learner will be able to: 1 Properly assess LVAD patients’ circulatory status; 2 appropriately resuscitate LVAD patients; 3 identify common LVAD complications; 4 evaluate and appropriately manage patients with LVAD malfunctions. Method: The method for this didactic session is cTBL.

  5. More vulnerability of left than right hippocampal damage in right-handed patients with post-traumatic stress disorder.

    Science.gov (United States)

    Shu, Xi-Ji; Xue, Li; Liu, Wei; Chen, Fu-Yin; Zhu, Cheng; Sun, Xiao-Hai; Wang, Xiao-Ping; Liu, Zhong-Cun; Zhao, Hu

    2013-06-30

    Previous studies have shown hippocampal abnormalities in people with post-traumatic stress disorder (PTSD), but findings of diminished volume in shortages in the hippocampus have been inconsistent. In this study, we investigated changes in hippocampal volume and neuronal metabolites in right-handed PTSD patients to determine their possible relationship(s) with PTSD severity. We performed a case-control study of 11 right-handed PTSD patients and 11 healthy controls using magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy ((1)H MRS). Hippocampal volume and metabolite ratios of N-acetylaspartate (NAA) to creatine (Cr) (NAA/Cr) and choline compounds (Cho) to Cr (Cho/Cr) were calculated. The severity of PTSD was evaluated by the Clinician-Administered PTSD Scale (CAPS). Significantly decreased left and total normalized hippocampal volumes were found in PTSD patients compared with controls (6.6% for the left hippocampus, 5.5% for total hippocampus). Also, the bilateral hippocampal NAA/Cr ratio of PTSD patients was significantly reduced compared with controls. The volume of the left hippocampus was negatively correlated to the CAPS total and CPAS-C scores. The left hippocampal NAA/Cr ratio was negatively correlated to the CAPS-total, CAPS-B, CAPS-C, and CAPS-D scores. The CAPS total and the CAPS-B scores were positively correlated to the Cho/Cr ratio of the right hippocampus. Our results indicate that hippocampal dysfunction is asymmetric in right-handed PTSD patients, with the left side affected more than the right. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  6. Remote Supratentorial Hemorrhage After Posterior Fossa Surgery: A Brief Case Report

    Directory of Open Access Journals (Sweden)

    Moscote-Salazar Luis Rafael

    2014-10-01

    Full Text Available The supratentorial hemorrhage after posterior fossa surgery is an unusual but delicate complication that carries high mortality and morbidity. A 50 year old woman presented vertigo 6 months of evolution, which worsened in the last 2 months accompanied by ataxia. She showed left cerebellar signs, had no focal motor or sensory deficits. A brain MRI identified cerebellopontine angle lesion with mass effect. The patient was treated on suboccipital craniectomy and resection of right posterior fossa tumor, the histopathological diagnosis was consistent with typical meningioma. (WHO Class I.

  7. Volumetric Analysis of Amygdala, Hippocampus, and Prefrontal Cortex in Therapy-Naive PTSD Participants

    Directory of Open Access Journals (Sweden)

    Ana Starcevic

    2014-01-01

    Full Text Available Objective. In our study we have hypothesized that volume changes of amygdala, hippocampus, and prefrontal cortex are more pronounced in male posttraumatic stress disorder participants. Material and Methods. We have conducted a study of 79 male participants who underwent MRI brain scanning. PTSD diagnosis was confirmed in 49 participants. After MRI was taken all scans were software based volume computed and statistically processed. Results. We found that left amygdala is the most significant parameter for distinction between PTSD participants and participants without PTSD. There were no significant differences in volumes of hippocampi and prefrontal cortices. Roc curve method outlined left amygdala AUC = 0.898 (95% CI = 0.830–0.967 and right amygdala AUC = 0.882 (95% CI = 0.810–0.954 in the group of PTSD participants which makes both variables highly statistically significant. Conclusion. The present investigation revealed significant volume decrease of left amygdala in PTSD patients. Concerning important functions of the amygdala and her neuroanatomical connections with other brain structures, we need to increase number of participants to clarify the correlation between impared amygdala and possible other different brain structures in participants with PTSD.

  8. Posterior Surgical Approach to Tuberculous Spondylitis | Shehu ...

    African Journals Online (AJOL)

    Objectives: Foraminotomy is a simple posterior surgical approach useful for treatment of radicular (nerve root) pain in TB spondylitis. It doesn't affect the stability of the facet joint, requires neither fusion nor implants. It is therefore cheap and affordable for patients with low income. We describe a simple form of posterior spinal ...

  9. Cervical disc hernia operations through posterior laminoforaminotomy

    OpenAIRE

    Yolas, Coskun; Ozdemir, Nuriye Guzin; Okay, Hilmi Onder; Kanat, Ayhan; Senol, Mehmet; Atci, Ibrahim Burak; Yilmaz, Hakan; Coban, Mustafa Kemal; Yuksel, Mehmet Onur; Kahraman, Umit

    2016-01-01

    Objective: The most common used technique for posterolateral cervical disc herniations is anterior approach. However, posterior cervical laminotoforaminomy can provide excellent results in appropriately selected patients with foraminal stenosis in either soft disc prolapse or cervical spondylosis. The purpose of this study was to present the clinical outcomes following posterior laminoforaminotomy in patients with radiculopathy. Materials and Methods: We retrospectively evaluated 35 patients ...

  10. Oxymetazoline in the treatment of posterior epistaxis.

    Science.gov (United States)

    Doo, G; Johnson, D S

    1999-08-01

    In this retrospective study, 36 patients were given oxymetazoline as a first step in treatment for posterior epistaxis. In 75% of the cases, epistaxis was effectively treated with oxymetazoline with no recurrent bleeding. All cases with recurrence resolved with continued administration of oxymetazoline. The results of this study propose a pharmacologic intervention for the treatment of posterior epistaxis.

  11. Posterior atlantooccipital subluxation in Down syndrome.

    Science.gov (United States)

    El-Khoury, G Y; Clark, C R; Dietz, F R; Harre, R G; Tozzi, J E; Kathol, M H

    1986-05-01

    Three Down syndrome patients with posterior atlantooccipital (AO) subluxation are described. All are asymptomatic. The subluxation becomes manifest during active extension of the neck and reduces in flexion. Methods of assessing posterior AO subluxation are discussed. The abnormality is attributed to ligamentous laxity in patients with Down syndrome.

  12. Evolution of the hippocampus in reptiles and birds.

    Science.gov (United States)

    Striedter, Georg F

    2016-02-15

    Although the hippocampus is structurally quite different among reptiles, birds, and mammals, its function in spatial memory is said to be highly conserved. This is surprising, given that structural differences generally reflect functional differences. Here I review this enigma in some detail, identifying several evolutionary changes in hippocampal cytoarchitecture and connectivity. I recognize a lepidosaurid pattern of hippocampal organization (in lizards, snakes, and the tuatara Sphenodon) that differs substantially from the pattern of organization observed in the turtle/archosaur lineage, which includes crocodilians and birds. Although individual subdivisions of the hippocampus are difficult to homologize between these two patterns, both lack a clear homolog of the mammalian dentate gyrus. The strictly trilaminar organization of the ancestral amniote hippocampus was gradually lost in the lineage leading to birds, and birds expanded the system of intrahippocampal axon collaterals, relative to turtles and lizards. These expanded collateral axon branches resemble the extensive collaterals in CA3 of the mammalian hippocampus but probably evolved independently of them. Additional examples of convergent evolution between birds and mammals are the loss of direct inputs to the hippocampus from the primary olfactory cortex and the general expansion of telencephalic regions that communicate reciprocally with the hippocampus. Given this structural convergence, it seems likely that some similarities in the function of the hippocampus between birds and mammals, notably its role in the ability to remember many different locations without extensive training, likewise evolved convergently. The currently available data do not allow for a strong test of this hypothesis, but the hypothesis itself suggests some promising new research directions. © 2015 Wiley Periodicals, Inc.

  13. Altered reward processing in the orbitofrontal cortex and hippocampus in healthy first-degree relatives of patients with depression

    DEFF Research Database (Denmark)

    Macoveanu, J; Knorr, U; Skimminge, A

    2014-01-01

    BACKGROUND: Healthy first-degree relatives of patients with major depression (rMD+) show brain structure and functional response anomalies and have elevated risk for developing depression, a disorder linked to abnormal serotonergic neurotransmission and reward processing. METHOD: In a two...... intervention compared to placebo. Conversely, for positive outcomes, the left hippocampus showed attenuated response to high wins in the rMD+ compared to the rMD- group. The SSRI intervention reinforced the hippocampal response to large wins. A subsequent structural analysis revealed that the abnormal neural...

  14. NeuN Expression Alterations in the Hippocampus Following Ecstasy Treatment

    Directory of Open Access Journals (Sweden)

    Ghasemi Moravej

    2016-05-01

    Full Text Available Background The administration of 3-4-methylenedioxymethamphetamine (MDMA leads to learning and memory impairment. Objectives Due to the effect of neurogenesis on memory and learning, in this study, we investigated the effects of MDMA on NeuN expression (a marker of neurogenesis in the hippocampus. Methods Adult male Wistar rats (weighing 200 - 250 g received a single intraperitoneal dose of 10 mg/kg of MDMA or were left undisrupted. The expression of NeuN was assessed using the immunohistochemistry method 7, 14, 28, and 60 days following MDMA administration. Results Our results showed that MDMA administration caused a decrease in NeuN expression in the experimental group compared with the control group. Conclusions These results suggest a negative correlation between MDMA administration and adult hippocampal neurogenesis.

  15. Posterior atlantooccipital membrane for duraplasty. Technical note.

    Science.gov (United States)

    Tubbs, R Shane; Wellons, John C; Blount, Jeffrey P; Oakes, W Jerry

    2002-09-01

    The authors describe the use of autogenetic posterior atlantooccipital (PAO) membrane for duraplasty following after posterior cranial fossa surgery. The PAO membrane is routinely exposed for procedures of the posterior cranial fossa and merely needs to be dissected free of the underlying dura mater. Recently this membrane was obtained in several pediatric patients following procedures of the posterior cranial fossa such as duraplasty in case of Chiari I malformation. No postoperative complications were found at 6-month follow-up examination. The advantages of this intervention include less manipulation of muscle and fascia than that involved in other procedures and, therefore, seemingly less postoperative pain and the negation of issues inherent with foreign-body graft sources. The authors believe this structure to be of use as a dural substitute in small dural openings of the posterior cranial fossa.

  16. Bilateral en-masse distalization of maxillary posterior teeth with skeletal anchorage: a case report

    Directory of Open Access Journals (Sweden)

    Saeed Noorollahian

    Full Text Available ABSTRACT Objective: The aim of this study was to introduce a new method for bilateral distal movement of the entire maxillary posterior segment. Case report: A 17-year-old girl with Class I skeletal malocclusion (end-to-end molar relationships, deviated midline and space deficiency for left maxillary canine was referred for orthodontic treatment. She did not accept maxillary first premolars extraction. A modified Hyrax appliance (Dentaurum Ispringen, Germany was used for bilateral distalization of maxillary posterior teeth simultaneously. Expansion vector was set anteroposteriorly. Posterior legs of Hyrax were welded to first maxillary molar bands. All posterior teeth on each side consolidated with a segment of 0.017 × 0.025-in stainless steel wire from the buccal side. Anterior legs of Hyrax were bent into eyelet form and attached to the anterior palate with two mini-screws (2 × 10 mm (Jeil Medical Corporation Seoul, South Korea. Hyrax opening rate was 0.8 mm per month. Lateral cephalometric radiographs were used to evaluate the extent of distal movement. 3.5-mm distalization of posterior maxillary teeth was achieved in five months. Results: A nearly bodily distal movement without anchorage loss was obtained. Conclusion: The mini-screw-supported modified Hyrax appliance was found to be helpful for achieving en-masse distal movement of maxillary posterior teeth.

  17. A Role for the Left Angular Gyrus in Episodic Simulation and Memory

    OpenAIRE

    Thakral, Preston P.; Madore, Kevin P.; Schacter, Daniel L.

    2017-01-01

    Functional magnetic resonance imaging (fMRI) studies indicate that episodic simulation (i.e., imagining specific future experiences) and episodic memory (i.e., remembering specific past experiences) are associated with enhanced activity in a common set of neural regions referred to as the core network. This network comprises the hippocampus, medial prefrontal cortex, and left angular gyrus, among other regions. Because fMRI data are correlational, it is unknown whether activity increases in c...

  18. Left Ventricular Pseudoaneurysm Perceived as a Left Lung Mass

    Directory of Open Access Journals (Sweden)

    Ugur Gocen

    2013-02-01

    Full Text Available Left ventricular pseudo-aneurysm is a rare complication of aneurysmectomy. We present a case of surgically-treated left ventricular pseudo-aneurysm which was diagnosed three years after coronary artery bypass grafting and left ventricular aneurysmectomy. The presenting symptoms, diagnostic evaluation and surgical repair are described. [Cukurova Med J 2013; 38(1.000: 123-125

  19. Synaptic Plasticity and Memory: New Insights from Hippocampal Left-Right Asymmetries.

    Science.gov (United States)

    El-Gaby, Mohamady; Shipton, Olivia A; Paulsen, Ole

    2015-10-01

    All synapses are not the same. They differ in their morphology, molecular constituents, and malleability. A striking left-right asymmetry in the distribution of different types of synapse was recently uncovered at the CA3-CA1 projection in the mouse hippocampus, whereby afferents from the CA3 in the left hemisphere innervate small, highly plastic synapses on the apical dendrites of CA1 pyramidal neurons, whereas those originating from the right CA3 target larger, more stable synapses. Activity-dependent modification of these synapses is thought to participate in circuit formation and remodeling during development, and further plastic changes may support memory encoding in adulthood. Therefore, exploiting the CA3-CA1 asymmetry provides a promising opportunity to investigate the roles that different types of synapse play in these fundamental properties of the CNS. Here we describe the discovery of these segregated synaptic populations in the mouse hippocampus, and discuss what we have already learnt about synaptic plasticity from this asymmetric arrangement. We then propose models for how the asymmetry could be generated during development, and how the adult hippocampus might use these distinct populations of synapses differentially during learning and memory. Finally, we outline the potential implications of this left-right asymmetry for human hippocampal function, as well as dysfunction in memory disorders such as Alzheimer's disease. © The Author(s) 2014.

  20. Congenital basis of posterior fossa anomalies

    Science.gov (United States)

    Cotes, Claudia; Bonfante, Eliana; Lazor, Jillian; Jadhav, Siddharth; Caldas, Maria; Swischuk, Leonard

    2015-01-01

    The classification of posterior fossa congenital anomalies has been a controversial topic. Advances in genetics and imaging have allowed a better understanding of the embryologic development of these abnormalities. A new classification schema correlates the embryologic, morphologic, and genetic bases of these anomalies in order to better distinguish and describe them. Although they provide a better understanding of the clinical aspects and genetics of these disorders, it is crucial for the radiologist to be able to diagnose the congenital posterior fossa anomalies based on their morphology, since neuroimaging is usually the initial step when these disorders are suspected. We divide the most common posterior fossa congenital anomalies into two groups: 1) hindbrain malformations, including diseases with cerebellar or vermian agenesis, aplasia or hypoplasia and cystic posterior fossa anomalies; and 2) cranial vault malformations. In addition, we will review the embryologic development of the posterior fossa and, from the perspective of embryonic development, will describe the imaging appearance of congenital posterior fossa anomalies. Knowledge of the developmental bases of these malformations facilitates detection of the morphological changes identified on imaging, allowing accurate differentiation and diagnosis of congenital posterior fossa anomalies. PMID:26246090

  1. Treatment implications of posterior fossa ependymoma subgroups.

    Science.gov (United States)

    Ramaswamy, Vijay; Taylor, Michael D

    2016-11-15

    Posterior fossa ependymoma comprises two distinct molecular entities, ependymoma_posterior fossa A (EPN_PFA) and ependymoma_posterior fossa B (EPN_PFB), with differentiable gene expression profiles. As yet, the response of the two entities to treatment is unclear. To determine the relationship between the two molecular subgroups of posterior fossa ependymoma and treatment, we studied a cohort of 820 patients with molecularly profiled, clinically annotated posterior fossa ependymomas. We found that the strongest predictor of poor outcome in patients with posterior fossa ependymoma across the entire age spectrum was molecular subgroup EPN_PFA, which was recently reported in the paper entitled "Therapeutic impact of cytoreductive surgery and irradiation of posterior fossa ependymoma in the molecular era: a retrospective multicohort analysis" in the Journal of Clinical Oncology. Patients with incompletely resected EPN_PFA tumors had a very poor outcome despite receiving adjuvant radiation therapy, whereas a substantial proportion of patients with EPN_PFB tumors can be cured with surgery alone.

  2. Microsurgical management of posterior circulation aneurysms

    Directory of Open Access Journals (Sweden)

    SHI Xiang-en

    2012-02-01

    Full Text Available Objective To retrospectively analyze effective methods for surgical management of posterior circulation aneurysms. Methods There were 42 patients with posterior circulation aneurysms [26 cases of basilar aneurysm (27 aneurysms, 16 cases of vertebral aneurysm (17 aneurysms]. There were 15 patients underwent bypass surgery [4 external carotid artery-P2 segment of posterior cerebral artery (ECA-P2, 2 internal carotid artery-P2 segment of posterior cerebral artery (ICA-P2, 2 internal maxillary artery-P2 segment of posterior cerebral artery (IMA-P2, 2 intracranial segment of vertebral artery-extracranial segment of vertebral artery, 5 occipital artery-posterior inferior cerebellar artery (OA-PICA] and 27 patients underwent simple surgical clipping. Results Activities of daily life of 37 patients recovered to normal (14 patients with aneurysm on the top of basilar artery, 3 with aneurysm on the trunk of basilar artery, 9 with vertebral aneurysm, 5 with posterior inferior cerebellar artery aneurysm, 4 with aneurysm on the junction of P1-P2 segment of posterior cerebral artery, 1 with superior cerebellar artery, and 1 with anterior inferior cerebellar aneurysm. None of them occurred operation-related neurological dysfunction. The recovery rate was 88.09% . Among the other patients, 1 with aneurysm on the top of basilar artery presented severe signs and symptoms of neurological defect and cannot take care of oneself, 2 patients (1 with aneurysm on the top of basilar artery, 1 with aneurysm on the trunk of basilar artery occurred brain stem hemorrhage after operation, and died at perioperative period, 2 with vertebral aneurysm relapsed and was cured after treatment. Conclusion Posterior circulation aneurysm which is not suitable for surgical clipping can be treated with intra? and extra?cranial vessel bypass. It may avoid the risk of surgical clipping of aneurysm.

  3. Interplay of hippocampus and prefrontal cortex in memory

    Science.gov (United States)

    Preston, Alison R.; Eichenbaum, Howard

    2013-01-01

    Recent studies on the hippocampus and the prefrontal cortex have considerably advanced our understanding of the distinct roles of these brain areas in the encoding and retrieval of memories, and of how they interact in the prolonged process by which new memories are consolidated into our permanent storehouse of knowledge. These studies have led to a new model of how the hippocampus forms and replays memories and how the prefrontal cortex engages representations of the meaningful contexts in which related memories occur, as well as how these areas interact during memory retrieval. Furthermore, they have provided new insights into how interactions between the hippocampus and prefrontal cortex support the assimilation of new memories into pre-existing networks of knowledge, called schemas, and how schemas are modified in this process as the foundation of memory consolidation. PMID:24028960

  4. High glycogen levels in the hippocampus of patients with epilepsy

    DEFF Research Database (Denmark)

    Dalsgaard, Mads K; Madsen, Flemming F; Secher, Niels H

    2006-01-01

    During intense cerebral activation approximately half of the glucose plus lactate taken up by the human brain is not oxidized and could replenish glycogen deposits, but the human brain glycogen concentration is unknown. In patients with temporal lobe epilepsy, undergoing curative surgery, brain...... biopsies were obtained from pathologic hippocampus (n=19) and from apparently 'normal' cortical grey and white matter. We determined the in vivo brain glycogen level and the activity of glycogen phosphorylase and synthase. Regional differences in glycogen concentration were examined similarly in healthy...... pigs (n=5). In the patients, the glycogen concentration in 'normal' grey and white matter was 5 to 6 mmol/L, but much higher in the hippocampus, 13.1+/-4.3 mmol/L (mean+/-s.d.; Pglycogen phosphorylase and synthase displayed the same pattern. In normal hippocampus from pigs...

  5. Episodic Memory and Beyond: The Hippocampus and Neocortex in Transformation.

    Science.gov (United States)

    Moscovitch, Morris; Cabeza, Roberto; Winocur, Gordon; Nadel, Lynn

    2016-01-01

    The last decade has seen dramatic technological and conceptual changes in research on episodic memory and the brain. New technologies, and increased use of more naturalistic observations, have enabled investigators to delve deeply into the structures that mediate episodic memory, particularly the hippocampus, and to track functional and structural interactions among brain regions that support it. Conceptually, episodic memory is increasingly being viewed as subject to lifelong transformations that are reflected in the neural substrates that mediate it. In keeping with this dynamic perspective, research on episodic memory (and the hippocampus) has infiltrated domains, from perception to language and from empathy to problem solving, that were once considered outside its boundaries. Using the component process model as a framework, and focusing on the hippocampus, its subfields, and specialization along its longitudinal axis, along with its interaction with other brain regions, we consider these new developments and their implications for the organization of episodic memory and its contribution to functions in other domains.

  6. Emission computer tomography of the left ventricle

    Energy Technology Data Exchange (ETDEWEB)

    Semmler, W.; Felix, R.; Calder, D.; Golde, G.; Botsch, H.

    1983-10-01

    Tomographic studies and time-dependent tomograms on phantoms and patients were carried out using a 7-pinhole collimator in order to study the clinical value of ECG-triggered tomographic radionuclid ventriculography. A suitable computer programme has been developed. The results have shown that it is possible to evaluate local contraction abnormalities by this method. Using a left oblique position of the collimator (LAO (45/sup 0/) - cranial (15/sup 0/)), emission computer tomography is aligned with the longitudinal axis for the heart. In this way, a single projection is sufficient to show the montility of the anterior and posterior walls and of the septum. Hypokinesis, akinesis or dyskinesis can be recognised visually. The localisation and extent of the defect can be determined through the 7-pinhole collimator. Reconstructed images of the triggered radionuclide scintigrams show excellent marginal definition. In the RAO projection the left ventricle can be seen without superimposition and images obtained which equal those of a first-pass technique.

  7. Does surgically fixation of pubic fracture increase the stability of the operated posterior pelvis?

    Science.gov (United States)

    Bodzay, Tamás; Sztrinkai, Gergely; Pajor, Sándor; Gál, Tamás; Jónás, Zoltán; Erdös, Péter; Váradi, Károly

    2014-01-01

    This study aims to investigate whether surgical treatment of pubic rami fractures increases the stability of the posterior pelvis. A finite element pelvic model with improved geometric and material characteristics was analyzed. By imitating a standing position, a type I Denis sacrum fracture and a unilateral pubis fracture, we measured the differences in tension and displacement. The posterior injury was treated with a direct plate synthesis or transsacral plate synthesis, while the pubis fracture was left without fixation or fixed with either a retrograde pubic screw or plate synthesis. The operative fixation of pubic rami fractures decreased the movement in the fracture gap not only at the site of the pubis fracture, but also at the site of the fixed sacrum fracture. The plate synthesis provided greater stability of the anterior fracture than the retrograde screw. The tensions in the implants were below the allowed values. We concluded that surgically fixation of pubic fracture increases the stability of the operated posterior pelvis.

  8. Arthroscopic Repair of Recurrent Posterior Shoulder Subluxation After Total Shoulder Arthroplasty: A Case Report.

    Science.gov (United States)

    Grieshaber-Bouyer, Ricardo; Gerber, Christian

    2017-01-01

    A 53-year-old man presented with osteoarthritis (Walch biconcave [B2] glenoid retroversion, 22°; glenohumeral subluxation index, 65%) and a partial rupture of the supraspinatus tendon in the left shoulder. Following anatomic total joint replacement, he developed disabling recurrent posterior subluxation despite a stable prosthesis and a correctly centered glenoid head, as observed with postoperative radiography and computed tomography. In order to avoid bone loss and the complications associated with revision arthroplasty, we performed arthroscopic reefing of the posterior capsule as an experimental minimally invasive treatment. The reduction in capsular volume successfully stabilized the shoulder for approximately 9 years; thereafter, the recurrence of instability ultimately required the conversion to a reverse prosthesis. Arthroscopic capsular reefing proved to be an effective treatment for posterior shoulder subluxations after total shoulder arthroplasty, and can be considered to avoid revision arthroplasty in young patients with a stable and correctly centered prosthesis.

  9. The right posterior inferior frontal gyrus contributes to phonological word decisions in the healthy brain

    DEFF Research Database (Denmark)

    Hartwigsen, Gesa; Price, Cathy J; Baumgaertner, Annette

    2010-01-01

    There is consensus that the left hemisphere plays a dominant role in language processing, but functional imaging studies have shown that the right as well as the left posterior inferior frontal gyri (pIFG) are activated when healthy right-handed individuals make phonological word decisions. Here we...... used online transcranial magnetic stimulation (TMS) to examine the functional relevance of the right pIFG for auditory and visual phonological decisions. Healthy right-handed individuals made phonological or semantic word judgements on the same set of auditorily and visually presented words while...... they received stereotactically guided TMS over the left, right or bilateral pIFG (n=14) or the anterior left, right or bilateral IFG (n=14). TMS started 100ms after word onset and consisted of four stimuli given at a rate of 10Hz and intensity of 90% of active motor threshold. Compared to TMS of aIFG, TMS of p...

  10. No strong evidence for lateralisation of word reading and face recognition deficits following posterior brain injury

    DEFF Research Database (Denmark)

    Gerlach, Christian; Marstrand, Lisbet; Starrfelt, Randi

    2014-01-01

    Face recognition and word reading are thought to be mediated by relatively independent cognitive systems lateralized to the right and left hemisphere respectively. In this case, we should expect a higher incidence of face recognition problems in patients with right hemisphere injury and a higher...... incidence of reading problems in patients with left hemisphere injury. We tested this hypothesis in a group of 31 patients with unilateral right or left hemisphere infarcts in the territory of the posterior cerebral arteries. In most domains tested (e.g., visual attention, object recognition, visuo......-construction, motion perception), we found that both patient groups performed significantly worse than a matched control group. In particular we found a significant number of face recognition deficits in patients with left hemisphere injury and a significant number of patients with word reading deficits following...

  11. Anterior hippocampus: the anatomy of perception, imagination and episodic memory.

    Science.gov (United States)

    Zeidman, Peter; Maguire, Eleanor A

    2016-03-01

    The brain creates a model of the world around us. We can use this representation to perceive and comprehend what we see at any given moment, but also to vividly re-experience scenes from our past and imagine future (or even fanciful) scenarios. Recent work has shown that these cognitive functions--perception, imagination and recall of scenes and events--all engage the anterior hippocampus. In this Opinion article, we capitalize on new findings from functional neuroimaging to propose a model that links high-level cognitive functions to specific structures within the anterior hippocampus.

  12. Disrupting posterior cingulate connectivity disconnects consciousness from the external environment.

    Science.gov (United States)

    Herbet, Guillaume; Lafargue, Gilles; de Champfleur, Nicolas Menjot; Moritz-Gasser, Sylvie; le Bars, Emmanuelle; Bonnetblanc, François; Duffau, Hugues

    2014-04-01

    Neurophysiological and neuroimaging studies including both patients with disorders of consciousness and healthy subjects with modified states of consciousness suggest a crucial role of the medial posteroparietal cortex in conscious information processing. However no direct neuropsychological evidence supports this hypothesis and studies including patients with restricted lesions of this brain region are almost non-existent. Using direct intraoperative electrostimulations, we showed in a rare patient that disrupting the subcortical connectivity of the left posterior cingulate cortex (PCC) reliably induced a breakdown in conscious experience. This acute phenomenon was mainly characterized by a transient behavioral unresponsiveness with loss of external connectedness. In all cases, when he regained consciousness, the patient described himself as in dream, outside the operating room. This finding suggests that functional integrity of the PPC connectivity is necessary for maintaining consciousness of external environment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Diagnostic gait pattern of a patient with longstanding left femoral nerve palsy: a case report.

    LENUS (Irish Health Repository)

    Burke, Neil G

    2010-12-01

    The gait pattern of a 35-year-old man with longstanding, left femoral nerve palsy was assessed using 3-dimensional kinematic and kinetic analysis. Stability of his left knee in stance was achieved by manipulating the external moments of the limb so that the ground reaction force passes in front of the knee joint. This compensatory mechanism of locking the knee in extension is reliant on the posterior capsular structures. The patient was managed conservatively and continued to walk without aids.

  14. Why Dora Left

    DEFF Research Database (Denmark)

    Gammelgård, Judy

    2017-01-01

    The question of why Dora left her treatment before it was brought to a satisfactory end and the equally important question of why Freud chose to publish this problematic and fragmentary story have both been dealt with at great length by Freud’s successors. Dora has been read by analysts, literary...... critics, and not least by feminists. The aim of this paper is to point out the position Freud took toward his patient. Dora stands out as the one case among Freud’s 5 great case stories that has a female protagonist, and reading the case it becomes clear that Freud stumbled because of an unresolved...... problem toward femininity, both Dora’s and his own. In Dora, it is argued, Freud took a new stance toward the object of his investigation, speaking from the position of the master. Freud presents himself as the one who knows, in great contrast to the position he takes when unraveling the dream. Here he...

  15. Reversible posterior leukoencephalopathy syndrome in children; MR imaging findings

    International Nuclear Information System (INIS)

    Lee, Sang Kwon; Kim, Yong Sun; Kwon, Soon Hak

    2001-01-01

    To find out the characteristic MR findings of reversible posterior leukoen-cephalopathy syndrome (RPLS) due to various causes in chldren. Eigh children with RPLS underwent MR imaging, and the findings were retrospectively analyzed. All eight were acutely hypertensive at the time of a neurotoxic episode. Three had intra-abdominal tumors (one adrenal pheochromo-cytoma, one para-aortic paraganglioma and one para-aortic ganglioneuroma encasing the left renal artery): three were being treated with cyclosporine: one was being treated with steroid: and one had hemolytric uremic syndrome. Initial cranial MR images were analyzed with particular emphasis on the distribution of the lesions. To assess possible sequelae, follow-up MR images were obtained in seven patients at least one week after the treatment of hypertension. Four underwent proton MR spectroscopy. Characteristic distribution of lesions in the occipital and posterior parietal lobes was identified in all cases regardless of the causes of RPLS. The cerebellum, basal ganglia, anterior parietal, and frontal lobe were involved in four, two, one, and one case, respectively. Cortical gray matter involvement was predominant in six and subcortical white matter involvement predominated in two patients. The distribution of lesions was bilateral and asymmetric. Gyriform enhancement was identified in six cases, and small hemorrhage was noted in one. In seven patients, the clinical and MR findings improved without sequelae on follow-up study. In one, proton MR spectroscopy demonstrated a high lactate peak at the time of the neurologic event. Nearnormal spectra were noted in three children who underwent proton MR spectroscopy after recovery. The MR findings of RPLS are characteristic in that lesions are distributed in the posterior region of the brain and they are reversible on follow-up study. In children with RPLS due to unknown causes, the possibility of intra-abdominal tumors should also be consiodered

  16. The posterior triangle in radical neck surgery.

    Science.gov (United States)

    Skolnik, E M; Yee, K F; Friedman, M; Golden, T A

    1976-01-01

    We evaluate the importance of cancer spread to the lymphatic system in the posterior triangle. The posterior triangle tissues of 51 radical neck specimens were serially sectioned and studied for metastic involvement. The findings were correlated with the findings in the anterior triangle and the primary tumor. Of the 51 neck operations performed, 25 were elective and 26 were therapeutic for carcinoma of the larynx, pharynx, and oral cavity. Metastasis in the anterior triangles was detected in 88.4% of the therapeutic group and in 24.0% of the elective group. However, no metastasis in the posterior triangel was found in either group, regardless of the site of the tumor. We suggest that the posterior triangle can be totally preserved in radical neck surgery, which may make preservation of the spinal accessory nerve a more likely practice.

  17. Primary Burkitt lymphoma in the posterior mediastinum.

    Science.gov (United States)

    Chaari, Zied; Charfi, Slim; Hentati, Abdessalem; Ayadi, Ines; Abid, Hanene; Frikha, Imed

    2015-11-01

    A 13-year-old boy was admitted to our hospital with complaints of posterior chest pain and dyspnea. Computed tomography and magnetic resonance imaging of the chest revealed a mass in the posterior mediastinum, extending from T8 to T11 with intraspinal involvement. A percutaneous core needle biopsy confirmed the diagnosis of Burkitt lymphoma. He was treated according to the Lymphoma Malignancy B protocol 2001 arm C3, but he presented with liver and brain relapses and died 7.5 months after admission. Although lymphoma is rarely localized in the posterior mediastinum, it should be considered in the differential diagnosis of posterior mediastinal masses in children. © The Author(s) 2015.

  18. Posterior alien hand syndrome: case report

    International Nuclear Information System (INIS)

    Rohde, S.; Weidauer, S.; Lanfermann, H.; Zanella, F.

    2002-01-01

    The alien hand syndrome (AHS) is involuntary uncontrolled movement of an arm with a sense of estrangement from the limb itself. AHS was initially used to describe interhemispheric disconnection phenomena in patients with lesions in the anterior corpus callosum, but it has been found in patients with posterior cerebral lesions without involvement of the corpus callosum, for example parietal infarcts or corticobasal degeneration. The posterior alien hand syndrome is less frequent and presents with nonpurposive behaviour like lifting the arm or writhing fingers. We report an 80-year-old woman with a posterior AHS of the dominant right hand. MRI showed atrophy of the pre- and postcentral gyri without involvement of the corpus callosum. We discuss the aetiology of the posterior AHS and the differences from the anterior varieties. (orig.)

  19. Congenital abnormalities of the posterior fossa.

    Science.gov (United States)

    Bosemani, Thangamadhan; Orman, Gunes; Boltshauser, Eugen; Tekes, Aylin; Huisman, Thierry A G M; Poretti, Andrea

    2015-01-01

    The frequency and importance of the evaluation of the posterior fossa have increased significantly over the past 20 years owing to advances in neuroimaging. Nowadays, conventional and advanced neuroimaging techniques allow detailed evaluation of the complex anatomic structures within the posterior fossa. A wide spectrum of congenital abnormalities has been demonstrated, including malformations (anomalies due to an alteration of the primary developmental program caused by a genetic defect) and disruptions (anomalies due to the breakdown of a structure that had a normal developmental potential). Familiarity with the spectrum of congenital posterior fossa anomalies and their well-defined diagnostic criteria is crucial for optimal therapy, an accurate prognosis, and correct genetic counseling. The authors discuss the spectrum of posterior fossa malformations and disruptions, with emphasis on neuroimaging findings (including diagnostic criteria), neurologic presentation, systemic involvement, prognosis, and risk of recurrence. RSNA, 2015

  20. Weakly supervised object detection with posterior regularization

    OpenAIRE

    Bilen, Hakan; Pedersoli, Marco; Tuytelaars, Tinne

    2014-01-01

    Bilen H., Pedersoli M., Tuytelaars T., ''Weakly supervised object detection with posterior regularization'', 25th British machine vision conference - BMVC 2014, 12 pp., September 1-5, 2014, Nottingham, UK.

  1. Posterior Fossa Tumors and Intellectual Impairment

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2005-01-01

    Full Text Available The effect of cerebellar damage on intellectual function in 76 children treated surgically for malignant posterior fossa tumor was investigated at the Gustave Roussy Institute, Villejuif, and the Department of Pediatric Neurosurgery, Necker Hospital, Paris, France.

  2. Patient with pontine warning syndrome and bilateral posterior internuclear ophthalmoplegia: case report

    Directory of Open Access Journals (Sweden)

    Su Li

    2010-06-01

    Full Text Available Abstract Background Capsular warning syndrome was first described in 1993, featured with repetitive episodes of motor and/or sensory dysfunction without cortical signs. Recently, it has been demonstrated that clinically typical capsular warning syndrome can be associated with pontine infarct and the term “pontine warning syndrome� was coined. Case Presentation A 54-year-old woman with a history of hypertension was seen with profound left-sided hemiplegia. She had had 3 episodes of left-sided weakness before complete hemiplegia. Her speech was slurred. Left central facial palsy and hemiglossoplegia were presented. Her left plantar response was extensor and bilateral posterior internuclear ophthalmoplegia was seen on neurologic examination. Biochemical tests revealed hyperglycemia and dyslipidemia on the next day. MRI demonstrated an acute right paramedian pontine infarct. The patient was commenced on oral clopidogrel, atorvastatin and acarbose. After 23 days of hospitalization, she was discharged with severe left hemiplegia. Conclusions 1 Pontine warning syndrome may be underestimated and understudied. 2 Posterior internuclear ophthalmoplegia is a rare clinical sign in cerebrovascular diseases, while it can help to locate a brainstem lesion rather than an internal capsular one. 3 Blood pressure lowing administration may be improper for patients with pontine warning syndrome.

  3. Bilateral posterior crystalline lens dislocations in an otherwise healthy child

    Directory of Open Access Journals (Sweden)

    AlShehri, Omar A.

    2017-10-01

    Full Text Available Introduction: Ectopia lentis is defined as a crystalline lens displacement, either partially or completely, due to zonular abnormalities. It can be a result of trauma, hereditary ocular disease, or part of systemic diseases, like Marfan syndrome and homocystinuria.Case description: We report a case of a medically free 16-year-old girl, who was referred to our hospital complaining of poor vision and a squint in both eyes since childhood. Her history included a traffic accident when she was one-year-old. She was previously diagnosed with alternating esotropia, which was treated with glasses, alternating patching, and bilateral Botox injections. On examination, she had a visual acuity of 6/7.5 with correction in the right eye and 6/6 with correction in the left eye. She had an esotropia of 60 prism diopters, which was partially corrected to 40 prism diopters for near and distance vision. Fundus examination showed myopic changes in each eye and dislocated lenses in the posterior pole at 6 o’clock. Our case was stable, so we used conservative management with contact lenses.Conclusion: Bilateral posterior lens dislocation is very rare. A proper examination is important and early diagnosis can prevent serious complications, such as retinal detachment or pupillary block glaucoma.

  4. Structural alterations in lateral prefrontal, parietal and posterior midline regions of men with chronic posttraumatic stress disorder.

    Science.gov (United States)

    Eckart, Cindy; Stoppel, Christian; Kaufmann, Jörn; Tempelmann, Claus; Hinrichs, Hermann; Elbert, Thomas; Heinze, Hans-Jochen; Kolassa, Iris-Tatjana

    2011-05-01

    So far, the neural network associated with posttraumatic stress disorder (PTSD) has been suggested to mainly involve the amygdala, hippocampus and medial prefrontal cortex. However, increasing evidence indicates that cortical regions extending beyond this network might also be implicated in the pathophysiology of PTSD. We aimed to investigate PTSD-related structural alterations in some of these regions. We enrolled highly traumatized refugees with and without (traumatized controls) PTSD and nontraumatized controls in the study. To increase the validity of our results, we combined an automatic cortical parcellation technique and voxel-based morphometry. In all, 39 refugees (20 with and 19 without PTSD) and 13 controls participated in the study. Participants were middle-aged men who were free of psychoactive substances and consumed little to no alcohol. Patients with PTSD (and to a lesser extent traumatized controls) showed reduced volumes in the right inferior parietal cortex, the left rostral middle frontal cortex, the bilateral lateral orbitofrontal cortex and the bilateral isthmus of the cingulate. An influence of cumulative traumatic stress on the isthmus of the cingulate and the lateral orbitofrontal cortex indicated that, at least in these regions, structural alterations might be associated with repeated stress experiences. Voxel-based morphometry analyses produced largely consistent results, but because of a poorer signal-to-noise ratio, conventional statistics did not reach significance. Although we controlled for several important confounding variables (e.g., sex, alcohol abuse) with our particular sample, this might limit the generalizibility of our data. Moreover, high comorbidity of PTSD and major depression hinders a definite separation of these conditions in our findings. Finally, the results concerning the lateral orbito frontal cortex should be interpreted with caution, as magnetic resonance imaging acquisition in this region is affected by a general

  5. Anatomical aspects of posterior fossa affecting lateral suboccipital approach. Evaluation by bone-window CT

    Energy Technology Data Exchange (ETDEWEB)

    Yamakami, Iwao; Yamaura, Akira; Ono, Junichi [Chiba Univ. (Japan). School of Medicine; Nakamura, Takao

    1996-02-01

    The high-resolution 1.5 mm-slice bone-window CT images of the posterior fossa in 40 patients with the cerebello-pontine angle tumor were reviewed regarding three anatomical aspects: the internal occipital crest (IOC), the posterior surface of the petrous bone, and the `petrous angle`. The IOC was sometimes prominent and protruded profoundly into the posterior fossa. The height of IOC from the inner table of the occipital bone was 9.6{+-}3.3 mm. The posterior surface of the petrous bone was convex to the posterior fossa in the most cases; the zenith of the prominence was the porus acusticus. The convexity of the posterior surface in the CT image was objectively evaluated by the `porus angle` made by two lines of A and B; the line A was the posterior half of the posterior surface of the petrous bone, and the line B was the anterior half of it. The `porus angle` in 40 cases was 28{+-}14deg in the left side, and 28{+-}12deg in the right side. The `petrous angle`, made by the cranial sagittal line and (the posterior half of ) the posterior surface of the petrous bone, was 61.8{+-}5.8deg and 62.7{+-}7.0deg, respectively. In the patient with a prominent IOC, the lateral suboccipital approach (LSA) with a unilateral suboccipital craniotomy may induce the compression of the cerebellar hemisphere by the brain retractor and the prominent IOC, and develop cerebellar contusion. Such a postoperative cerebellar complication can be avoided by a large suboccipital craniotomy with the resection of the prominent IOC extending contralaterally. The severe convexity of the posterior surface of the petrous bone, i.e. the large `porus angle`, makes it difficult to get the view of the petroclival region in the LSA. The larger is the `petrous angle`, the less cerebellar compression is necessary for the approach to the cerebello-pontine angle by the LSA; the large `petrous angle` is advantageous to the approach. (H.O.).

  6. Luxación posterior de hombro

    OpenAIRE

    Matson-Carballo Gustavo; Ramírez-Castro Jéssica Lorena

    2013-01-01

    Introduction: posterior shoulder dislocation is an infrequent pathology that is associated to electroshocks, convulsions and trauma in flexion and adduction of the superior extremities. Due to its clinical signs are slightly evident, it could be overlooked and become chronic. It might be accompanied of fractures of the proximal humerus. Clinical case: 39 years-of-age patient who consulted to the emergency service for presenting signs of posterior shoulder dislocation, without p...

  7. Longevity of posterior tooth dental restorations.

    Science.gov (United States)

    Christensen, Gordon J

    2005-02-01

    Several forms of restorative techniques are used for posterior teeth. They vary significantly in cost and longevity. The following restorative concepts are the most commonly used: amalgam, resin-based composite, PFM, cast gold alloy restorations and all-ceramic restorations. I suggest that patients be informed about the potential longevity of restorative treatment for posterior teeth as they make decisions about treatment for their oral restorative needs.

  8. Posterior atlantoaxial dislocation without odontoid fracture

    International Nuclear Information System (INIS)

    Chaudhary, Reema; Raut, Abhijit; Chaudhary, Kshitij; Metkar, Umesh; Rathod, Ashok; Sanghvi, Darshana

    2008-01-01

    We report a case of posterior atlantoaxial dislocation without a fracture of the odontoid in a 35-year-old woman. There have been nine reported cases of similar injury in the English literature. The integrity of the transverse ligament following posterior atlantoaxial dislocations has not been well documented in these reports. In the present case, MRI revealed an intact transverse ligament, which probably contributed to the stability of the C1-C2 complex following closed reduction. (orig.)

  9. Vermian agenesis without posterior fossa cyst

    International Nuclear Information System (INIS)

    Adamsbaum, C.; Moreau, V.; Bulteau, C.; Burstyn, J.; Lair Milan, F.; Kalifa, G.

    1994-01-01

    We report 11 cases of vermian partial agenesis without posterior fossa cyst or hemispheric abnormalities. Characteristic MR signs were: absence of the posterior lobe, hypoplasia of the anterior lobe, a narrow sagittal cleft separating the hemispheres (''buttocks sign'') and fourth ventricle deformity. The main clinical signs were complex oculomotor dysfunction and developmental delay. None of the patients had respiratory symptoms. Consideration is given to the relationship between Joubert syndrome and this entity as well as to embroyological data. (orig.)

  10. Behavioral Disorders in Association with Posterior Callosal and Frontal Cerebral Infarction

    Directory of Open Access Journals (Sweden)

    J. P. Lejeune

    1993-01-01

    Full Text Available Behavioral disorders were a prominent clinical feature after the surgical treatment of an anterior communicating artery aneurysm rupture in a 44-year-old man. Callosal apraxia was associated with an alien hand. The latter remained 1 year after surgery while diagonistic apraxia disappeared after 3 months. Other callosal signs included left agraphia, tactile anomia and auditory suppression. MRI revealed posterior callosal infarction and a right frontal infarct. The association of diagonistic apraxia and alien hand is rarely reported.

  11. Management of a posterior mediastinal Gardner fibroma causing critical airway stenosis in a resource limited setting

    Directory of Open Access Journals (Sweden)

    Katie Clouthier, DO

    2017-05-01

    Full Text Available In developed countries, surgeons and anesthesiologists approach the mediastinal mass causing airway compression with prudence and trepidation. Resource-limited settings provide unique challenges in the diagnosis and management of patients with critical airway compression. We report the successful treatment of a patient in Port-au-Prince, Haiti with a posterior mediastinal mass that filled the left chest cavity and caused critical airway stenosis. The pathology revealed a Gardner Fibroma, which is rarely associated with mediastinal airway obstruction.

  12. Changes in fMRI activation in anterior hippocampus and motor cortex during memory retrieval after an intense exercise intervention.

    Science.gov (United States)

    Wagner, Gerd; Herbsleb, Marco; de la Cruz, Feliberto; Schumann, Andy; Köhler, Stefanie; Puta, Christian; Gabriel, Holger W; Reichenbach, Jürgen R; Bär, Karl-Jürgen

    2017-03-01

    Strong evidence indicates that regular aerobic training induces beneficial effects on cognitive functions. The present controlled fMRI study was designed to investigate the impact of a short-term intense aerobic exercise on the pattern of functional activation during the retrieval of learned pair-associates in 17 young and healthy male adults compared to 17 matched control subjects. We further aimed to relate putative changes in hippocampal activation to postulated changes in the exercised-induced brain derived neurotrophic factor (BDNF). The supervised exercise program was performed on a bicycle ergometer and lasted six weeks, with three aerobic sessions per week. We found profound improvement of physical fitness in most subjects indicated by the target parameter 'individual anaerobic threshold'. Significant improvements in the cognitive performance were detected in the exercise group, but also in the control group. We observed significant differences in the activation pattern of the left anterior hippocampus during the pair-associates task after the intervention. We could also show a significant positive correlation between changes in exercise-induced BDNF and left anterior hippocampal activation. Moreover, we observed the brain's motor network to be significantly stronger activated after the exercise intervention. Thus, our results suggest BDNF dependent activation changes of the hippocampus in addition to previously described structural changes after exercise. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Delayed Single Stage Perineal Posterior Urethroplasty

    International Nuclear Information System (INIS)

    Ali, S.; Shahnawaz; Shahzad, I.; Baloch, M. U.

    2015-01-01

    Objective: To determine the delayed single stage perineal posterior urethroplasty for treatment of posterior urethral stricture/distraction defect. Study Design: Descriptive case series. Place and Duration of Study: Department of Urology, Jinnah Postgraduate Medical Centre, Karachi, from January 2009 to December 2011. Methodology: Patients were selected for delayed single stage perineal posterior urethroplasty for treatment of posterior urethral stricture / distraction defect. All were initially suprapubically catheterized followed by definitive surgery after at least 3 months. Results: Thirty male patients were analyzed with a mean follow-up of 10 months, 2 patients were excluded as they developed failure in first 3 months postoperatively. Mean patients age was 26.25 ± 7.9 years. On follow-up, 7 patients (23.3 percentage) experienced recurrent stricture during first 10 months. Five (16.6 percentage) patients were treated successfully with single direct visual internal urethrotomy. Two patients (6.6 percentage) had more than one direct visual internal urethrotomy and considered failed. Re-do perineal urethroplasty was eventually performed. The overall success rate was 93.3 percentage with permissive criteria allowing single direct visual internal urethrotomy and 76.6% with strict criteria allowing no more procedures postoperatively. Conclusion: Posterior anastomotic urethroplasty offers excellent long-term results to patients with posterior urethral trauma and distraction defect even after multiple prior procedures. (author)

  14. Early endoscopic realignment in posterior urethral injuries.

    Science.gov (United States)

    Shrestha, B; Baidya, J L

    2013-01-01

    Posterior urethral injury requires meticulous tertiary care and optimum expertise to manage successfully. The aim of our study is to describe our experiences with pelvic injuries involving posterior urethra and their outcome after early endoscopic realignment. A prospective study was carried out in 20 patients with complete posterior urethral rupture, from November 2007 till October 2010. They presented with blunt traumatic pelvic fracture and underwent primary realignment of posterior urethra in our institute. The definitive diagnosis of urethral rupture was made after retrograde urethrography and antegrade urethrography where applicable. The initial management was suprapubic catheter insertion after primary trauma management in casualty. After a week of conservative management with intravenous antibiotics and pain management, patients were subjected to the endoscopic realignment. The follow up period was at least six months. The results were analyzed with SPSS software. After endoscopic realignment, all patients were advised CISC for the initial 3 months. All patients voided well after three months of CISC. However, 12 patients were lost to follow up by the end of 6 postoperative months. Out of eight remaining patients, two had features of restricture and were managed with DVU followed by CISC again. One patient with restricture had some degree of erectile dysfunction who improved significantly after phospodiesterase inhibitors. None of the patients had features of incontinence. Early endoscopic realignment of posterior urethra is a minimally invasive modality in the management of complete posterior urethral injury with low rates of incontinence and impotency.

  15. Traumatic lesions of the posterior urethra.

    Science.gov (United States)

    Velarde-Ramos, L; Gómez-Illanes, R; Campos-Juanatey, F; Portillo-Martín, J A

    2016-11-01

    The posterior urethral lesions are associated with pelvis fractures in 5-10% of cases. The posterior urethra is attached to the pelvis bone by puboprostatic ligaments and the perineal membrane, which explains why disruption of the pelvic ring can injure the urethra at this level. To identify suspected cases of posterior urethral trauma and to perform the diagnosis and its immediate or deferred management. Search in PubMed of articles related to traumatic posterior urethral lesions, written in English or Spanish. We reviewed the relevant publications including literature reviews and chapters from books related to the topic. With patients with pelvis fractures, we must always rule out posterior urethral lesions. The diagnostic examination of choice is retrograde urethrography, which, along with the severity of the condition, will determine the management in the acute phase and whether the treatment will be performed immediately or deferred. Early diagnosis and proper acute management decrease the associated complications, such as strictures, urinary incontinence and erectile dysfunction. Despite the classical association between posterior urethral lesions and pelvic fractures, the management of those lesions (whether immediate or deferred) remains controversial. Thanks to the growing interest in urethral disease, there are an increasing number of studies that help us achieve better management of these lesions. Copyright © 2016 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Non-compact left ventricle/hypertrabeculated left ventricle

    International Nuclear Information System (INIS)

    Restrepo, Gustavo; Castano, Rafael; Marmol, Alejandro

    2005-01-01

    Non-compact left ventricle/hypertrabeculated left ventricle is a myocardiopatie produced by an arrest of the normal left ventricular compaction process during the early embryogenesis. It is associated to cardiac anomalies (congenital cardiopaties) as well as to extracardial conditions (neurological, facial, hematologic, cutaneous, skeletal and endocrinological anomalies). This entity is frequently unnoticed, being diagnosed only in centers with great experience in the diagnosis and treatment of myocardiopathies. Many cases of non-compact left ventricle have been initially misdiagnosed as hypertrophic myocardiopatie, endocardial fibroelastosis, dilated cardiomyopatie, restrictive cardiomyopathy and endocardial fibrosis. It is reported the case of a 74 years old man with a history of chronic arterial hypertension and diabetes mellitus, prechordial chest pain and mild dyspnoea. An echocardiogram showed signs of non-compact left ventricle with prominent trabeculations and deep inter-trabecular recesses involving left ventricular apical segment and extending to the lateral and inferior walls. Literature on this topic is reviewed

  17. CHRONIC DEVELOPMENTAL LEAD EXPOSURE REDUCES NEUROGENESIS IN ADULT HIPPOCAMPUS.

    Science.gov (United States)

    CHRONIC DEVELOPMENTAL LEAD EXPOSURE REDUCES NEUROGENESIS IN ADULT HIPPOCAMPUS. ME Gilbert1, ME Kelly2, S. Salant3, T Shafer1, J Goodman3 1Neurotoxicology Div, US EPA, RTP, NC, 27711, 2Children's Hospital, Philadelphia, PA, 19104, 3Helen Hayes Hospital, Haverstraw, NY, 10993. ...

  18. The Learning Hippocampus: Education and Experience-Dependent Plasticity

    Science.gov (United States)

    Wenger, Elisabeth; Lövdén, Martin

    2016-01-01

    The hippocampal formation of the brain plays a crucial role in declarative learning and memory while at the same time being particularly susceptible to environmental influences. Education requires a well-functioning hippocampus, but may also influence the development of this brain structure. Understanding these bidirectional influences may have…

  19. Adult Neurogenesis in the Mammalian Hippocampus: Why the Dentate Gyrus?

    Science.gov (United States)

    Drew, Liam J.; Fusi, Stefano; Hen, René

    2013-01-01

    In the adult mammalian brain, newly generated neurons are continuously incorporated into two networks: interneurons born in the subventricular zone migrate to the olfactory bulb, whereas the dentate gyrus (DG) of the hippocampus integrates locally born principal neurons. That the rest of the mammalian brain loses significant neurogenic capacity…

  20. Remodeling of Hippocampal Synapses After Hippocampus-Dependent Associative Learning

    NARCIS (Netherlands)

    Geinisman, Yuri; Disterhoft, John F.; Gundersen, Hans Jørgen G.; McEchron, Matthew D.; Persina, Inna S.; Power, John M.; Zee, Eddy A. van der; West, Mark J.

    2000-01-01

    The aim of this study was to determine whether hippocampus-dependent associative learning involves changes in the number and/or structure of hippocampal synapses. A behavioral paradigm of trace eyeblink conditioning was used. Young adult rabbits were given daily 80 trial sessions to a criterion of

  1. Amygdala and Hippocampus Enlargement during Adolescence in Autism

    Science.gov (United States)

    Groen, Wouter; Teluij, Michelle; Buitelaar, Jan; Tendolkar, Indira

    2010-01-01

    Objective: The amygdala and hippocampus are key components of the neural system mediating emotion perception and regulation and are thought to be involved in the pathophysiology of autism. Although some studies in children with autism suggest that there is an enlargement of amygdala and hippocampal volume, findings in adolescence are sparse.…

  2. Amygdala and hippocampus enlargement during adolescence in autism.

    NARCIS (Netherlands)

    Groen, W.B.; Teluij, M.; Buitelaar, J.K.; Tendolkar, I.

    2010-01-01

    OBJECTIVE: The amygdala and hippocampus are key components of the neural system mediating emotion perception and regulation and are thought to be involved in the pathophysiology of autism. Although some studies in children with autism suggest that there is an enlargement of amygdala and hippocampal

  3. Stress Effects on the Hippocampus: A Critical Review

    Science.gov (United States)

    Kim, Eun Joo; Pellman, Blake; Kim, Jeansok J.

    2015-01-01

    Uncontrollable stress has been recognized to influence the hippocampus at various levels of analysis. Behaviorally, human and animal studies have found that stress generally impairs various hippocampal-dependent memory tasks. Neurally, animal studies have revealed that stress alters ensuing synaptic plasticity and firing properties of hippocampal…

  4. Fornix deep brain stimulation enhances acetylcholine levels in the hippocampus.

    Science.gov (United States)

    Hescham, Sarah; Jahanshahi, Ali; Schweimer, Judith V; Mitchell, Stephen N; Carter, Guy; Blokland, Arjan; Sharp, Trevor; Temel, Yasin

    2016-11-01

    Deep brain stimulation (DBS) of the fornix has gained interest as a potential therapy for advanced treatment-resistant dementia, yet the mechanism of action remains widely unknown. Previously, we have reported beneficial memory effects of fornix DBS in a scopolamine-induced rat model of dementia, which is dependent on various brain structures including hippocampus. To elucidate mechanisms of action of fornix DBS with regard to memory restoration, we performed c-Fos immunohistochemistry in the hippocampus. We found that fornix DBS induced a selective activation of cells in the CA1 and CA3 subfields of the dorsal hippocampus. In addition, hippocampal neurotransmitter levels were measured using microdialysis before, during and after 60 min of fornix DBS in a next experiment. We observed a substantial increase in the levels of extracellular hippocampal acetylcholine, which peaked 20 min after stimulus onset. Interestingly, hippocampal glutamate levels did not change compared to baseline. Therefore, our findings provide first experimental evidence that fornix DBS activates the hippocampus and induces the release of acetylcholine in this region.

  5. The posterior condylar offset ratio and femoral anatomy in anterior versus posterior referencing total knee arthroplasty.

    Science.gov (United States)

    Almeida, P H; Vilaça, A

    2015-10-01

    The preservation of joint anatomy is one of the key issues in total knee arthroplasty. The effect of the prosthesis' referencing system, relative to femoral anatomy, remains unknown. It was sought to determine if femoral anatomy, following total knee arthroplasty is better maintained using either anterior referencing or posterior referencing prosthesis. The posterior condylar offset ratio (PCOR) was employed for preoperative and postoperative radiographic comparison of femoral condyles. It was hypothesized that posterior referencing prosthesis would better restore condylar morphology. Sixty-six patients undergoing a total knee arthroplasty with anterior referenced Zimmer(®) NexGen(®) LPS prosthesis and ninety-one with posterior referenced Tornier(®) HLS Noetos(®) were divided into two groups according to the prosthetic model used and retrospectively compared. PCOR was calculated as the quotient of the distance between the posterior condylar border and the tangent to the posterior cortex of the femoral diaphysis, and the distance between the posterior condylar border and the tangent to the anterior cortex of the femoral diaphysis. PCOR was determined preoperatively and postoperatively and compared within each group and between both groups. An increase in the PCOR (Panterior referencing and posterior referencing models. No difference was noted when the postoperative PCOR was compared between both groups (P=0.61). Both anterior and posterior referencing prosthesis lead to a similar increase of the PCOR following total knee arthroplasty. Level IV. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  6. Mechanical discordance between left atrium and left atrial appendage

    Directory of Open Access Journals (Sweden)

    Arash Khamooshian

    2018-01-01

    Full Text Available During standard transesophageal echocardiographic examinations in sinus rhythm (SR patients, the left atrial appendage (LAA is not routinely assessed with Doppler. Despite having a SR, it is still possible to have irregular activity in the LAA. This situation is even more important for SR patients where assessment of the left atrium is often foregone. We describe a case where we encountered this situation and briefly review how to assess the left atrium and its appendage in such a case scenario.

  7. Unraveling the Role of the Hippocampus in Reversal Learning.

    Science.gov (United States)

    Vilà-Balló, Adrià; Mas-Herrero, Ernest; Ripollés, Pablo; Simó, Marta; Miró, Júlia; Cucurell, David; López-Barroso, Diana; Juncadella, Montserrat; Marco-Pallarés, Josep; Falip, Mercè; Rodríguez-Fornells, Antoni

    2017-07-12

    Research in reversal learning has mainly focused on the functional role of dopamine and striatal structures in driving behavior on the basis of classic reinforcement learning mechanisms. However, recent evidence indicates that, beyond classic reinforcement learning adaptations, individuals may also learn the inherent task structure and anticipate the occurrence of reversals. A candidate structure to support such task representation is the hippocampus, which might create a flexible representation of the environment that can be adaptively applied to goal-directed behavior. To investigate the functional role of the hippocampus in the implementation of anticipatory strategies in reversal learning, we first studied, in 20 healthy individuals (11 women), whether the gray matter anatomy and volume of the hippocampus were related to anticipatory strategies in a reversal learning task. Second, we tested 20 refractory temporal lobe epileptic patients (11 women) with unilateral hippocampal sclerosis, who served as a hippocampal lesion model. Our results indicate that healthy participants were able to learn the task structure and use it to guide their behavior and optimize their performance. Participants' ability to adopt anticipatory strategies correlated with the gray matter volume of the hippocampus. In contrast, hippocampal patients were unable to grasp the higher-order structure of the task with the same success than controls. Present results indicate that the hippocampus is necessary to respond in an appropriately flexible manner to high-order environments, and disruptions in this structure can render behavior habitual and inflexible. SIGNIFICANCE STATEMENT Understanding the neural substrates involved in reversal learning has provoked a great deal of interest in the last years. Studies with nonhuman primates have shown that, through repetition, individuals are able to anticipate the occurrence of reversals and, thus, adjust their behavior accordingly. The present

  8. [Left-handedness and health].

    Science.gov (United States)

    Milenković, Sanja; Belojević, Goran; Kocijancić, Radojka

    2010-01-01

    Hand dominance is defined as a proneness to use one hand rather than another in performing the majority of activities and this is the most obvious example of cerebral lateralization and an exclusive human characteristic. Left-handed people comprise 6-14% of the total population, while in Serbia, this percentage is 5-10%, moving from undeveloped to developed environments, where a socio-cultural pressure is less present. There is no agreement between investigators who in fact may be considered a left-handed person, about the percentage of left-handers in the population and about the etiology of left-handedness. In the scientific literature left-handedness has been related to health disorders (spine deformities, immunological disorders, migraine, neurosis, depressive psychosis, schizophrenia, insomnia, homosexuality, diabetes mellitus, arterial hypertension, sleep apnea, enuresis nocturna and Down Syndrome), developmental disorders (autism, dislexia and sttutering) and traumatism. The most reliable scientific evidences have been published about the relationship between left-handedness and spinal deformities in school children in puberty and with traumatism in general population. The controversy of other results in up-to-now investigations of health aspects of left-handedness may partly be explained by a scientific disagreement whether writing with the left hand is a sufficient criterium for left-handedness, or is it necessary to investigate other parameters for laterality assessment. Explanation of health aspects of left-handedness is dominantly based on Geschwind-Galaburda model about "anomalous" cerebral domination, as a consequence of hormonal disbalance.

  9. Severe Hypoplasia of Posterior Mitral Valve Leaflet Presented with Atypical Chest Pain: A Case Report

    Directory of Open Access Journals (Sweden)

    Afsoon Fazlinezhad

    2016-02-01

    Full Text Available Introduction Absence of the posterior mitral leaflet is usually fatal for fetus in utero. Although hypoplasia of the posterior mitral leaflet is usually present in children with symptomatic mitral regurgitation, it is usually evident in a few cases of asymptomatic adults. We decided to introduce a rare case with hypoplasia of the posterior mitral valve leaflet associated with aortic stenosis. Case Presentation A 24-year-old man was admitted with a history of atypical chest pain. The patient had a normal psychophysical growth. The physical examination showed 4/6 mid- systolic ejection murmurs over the left sternal border. Chest roentgenogram was normal and the electrocardiogram showed sinus rhythm with mild LVH. Meanwhile, the echocardiography revealed severe elongated sail- like anterior leaflet and hypoplasia of the posterior mitral leaflet with moderate valvular aortic stenosis. MR grade was mild due to the complete coverage of anterior mitral leaflet. Moreover, LV function and pulmonary arterial pressure were reported normal. Conclusions This abnormality was tolerated since adulthood and mitral regurgitation was gradually developed due to annulus dilation. Therefore, the posterior mitral leaflet did not have a significant impact on mitral valve performance.

  10. Mental Number Line Disruption in a Right-Neglect Patient after a Left-Hemisphere Stroke

    Science.gov (United States)

    Pia, Lorenzo; Corazzini, Luca Latini; Folegatti, Alessia; Gindri, Patrizia; Cauda, Franco

    2009-01-01

    A right-neglect patient with focal left-hemisphere damage to the posterior superior parietal lobe was assessed for numerical knowledge and tested on the bisection of numerical intervals and visual lines. The semantic and verbal knowledge of numbers was preserved, whereas the performance in numerical tasks that strongly emphasize the visuo-spatial…

  11. Sex differences in microglial phagocytosis in the neonatal hippocampus.

    Science.gov (United States)

    Nelson, Lars H; Warden, Spencer; Lenz, Kathryn M

    2017-08-01

    Microglia regulate brain development through many processes, such as promoting neurogenesis, supporting cell survival, and phagocytizing progenitor, newly-born, and dying cells. Many of these same developmental processes show robust sex differences, yet very few studies have assessed sex differences in microglia function during development. Hormonally-induced sexual differentiation of the brain occurs during the perinatal period, thus we examined sex differences in microglial morphology, phagocytosis, and proliferation in the hippocampus during the early postnatal period. We found that the neonatal female hippocampus had significantly more microglia with phagocytic cups than the male hippocampus. We subsequently found that female microglia phagocytized more neural progenitor cells and healthy cells compared to males, but there were no sex differences in the number of newly-born or dying cells targeted by microglial phagocytosis. We found that the number of phagocytic microglia in females was reduced to male-typical levels by treatment with estradiol, the hormone responsible for masculinizing the rodent brain. Females also had higher expression of several phagocytic pathway genes in the hippocampus compared to males. In contrast to robust sex differences in phagocytic microglia, we found no sex differences in the number of microglia with amoeboid, transitioning, or ramified morphologies or differences in three-dimensional reconstructions of microglial morphology. While we did not find a baseline sex difference in microglial proliferation during or following the prenatal gonadal hormone surge in males, we found that estradiol treatment increased microglia proliferation in females. Overall, these data show that there are important sex differences in microglia function in the hippocampus during the early neonatal period. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. [BIOMECHANICS STUDY ON ACETABULAR POSTERIOR WALL FRACTURE].

    Science.gov (United States)

    Tang, Yang; Hu Xiaopeng; Lu, Xiongwei; Zhang, Yuntong; Zhang, Chuncai; Wang, Panfeng; Zhao, Xue

    2015-08-01

    To study the experimental biomechanics of acetabular posterior wall fractures so as to provide theoretical basis for its clinical treatment. Six formalin-preserved cadaveric pelvises were divided into groups A and B (n=3). The fracture models of superior-posterior wall and inferior-posterior wall of the acetabulum were created on both hips in group A; fractures were fixed with two interfragmentary screws and a locking reconstruction plate. The fracture models of superior-posterior wall of acetabulum were created on both hips in group B; fractures were fixed with two interfragmentary screws and a locking reconstruction plate at one side, and with acetabular tridimensional memory fixation system (ATMFS) at the other side. The biomechanical testing machine was used to load to 1 500 N at 10 mm/min speed for 30 seconds. The displacement of superior and inferior fracture sites was analyzed with the digital image correlation technology. No fracture or internal fixation breakage occurred during loading and measuring; the displacement valuess of the upper and lower fracture lines were below 2 mm (the clinically tolerable maximum value) in 2 groups. In group A, the displacement values of the upper and lower fracture lines at superior-posterior wall fracture site were significantly higher than those at inferior-posterior wall fracture site (P fracture line were significantly higher than those of lower fracture line (P fracture types. In group B, the displacement values of the upper and lower fracture lines at the side fixed with screws and a locking reconstruction plate were similar to the values at the side fixed with ATMFS, all being close to 2 mm; the displacement values of the upper fracture line were significantly higher than those of lower fracture line (P acetabulum is much greater than that of the inferior-posterior wall of acetabulum and they should be discriminated, which might be the reasons of reduction loss, femoral head subluxation, and traumatic arthritis

  13. Morphologic expression of the left coronary artery in pigs. An approach in relation to human heart

    Directory of Open Access Journals (Sweden)

    Fabian Alejandro Gómez

    2014-04-01

    Full Text Available Introduction: In spite of its importance as an experimental model, the information on the left coronary artery in pigs is sparse. Objective: To determine the morphologic features of the left coronary artery in pigs. Methods: We evaluated 158 pig hearts. The left coronary artery was perfused with synthetic resin after their ostia had been catheterized. Diameters and courses of the vascular beds were measured with an electronic caliper (Mitutoyo(r. Results: The diameter of left coronary artery was 6.98 ± 1.56 mm and its length was 3.51±0.99 mm. It was found to end up by bifurcating itself into the anterior interventricular artery and the circumflex artery in 79% of the cases, and by trifurcating in 21% of the cases, with the presence of the diagonal artery. The anterior interventricular artery ended up at the apex in 79.7% of the cases, and the circumflex artery at the posterior aspect of the left ventricle in 64% of the case, this artery never reached the posterior interventricular sulcus. An anastomosis between the terminal branches of the anterior interventricular artery and the posterior interventricular artery was found in 7.6% of the specimens. The antero-superior branch of the anterior interventricular artery occurred in 89.9% of the hearts. A left marginal branch was observed in 87.9% of the cases with a diameter of 2.25±0.55 mm. Conclusion: Compared with humans, pigs have shorter left coronary artery trunks and branches; even the circumflex artery never reaches the posterior interventricular sulcus. Our findings are useful for the design of experimental hemodynamic and procedural models.

  14. Reduced right posterior hippocampal volume in women with recurrent familial pure depressive disorder.

    Science.gov (United States)

    Nifosì, Francesco; Toffanin, Tommaso; Follador, Halima; Zonta, Filippo; Padovan, Giordano; Pigato, Giorgio; Carollo, Carla; Ermani, Mario; Amistà, Pietro; Perini, Giulia Ida

    2010-10-30

    Volumetric changes in mood-relevant distributed limbic/paralimbic structures have been reported in the recent literature on the course of mood disorders. Patients with unipolar and bipolar disorders have been found to have smaller hippocampal and anterior cingulate volumes. We examined hippocampal, amygdalar and anterior cingulate cortex (ACC) volumes in female patients with recurrent familial pure depressive disorder (rFPDD). We used semi-automated software for magnetic resonance imaging (MRI) to measure the volumes of the hippocampus, amygdala, ACC and subgenual prefrontal cortex (SGPFC) in 15 female patients with familial recurrent major depression (MD) and 15 healthy female subjects. Analysis of covariance, with whole brain volume as covariate, was used to compare volumetric measurements in the two groups. Volumes of the right hippocampal body and tail were significantly smaller in female patients with familial depressive disorder than in healthy subjects. Our data provide evidence of structural lateralized hippocampal body and tail abnormalities in women with familial history and recurrent episodes of depression. Although global reduction of hippocampal volume has been widely reported, data on lateralized regional reductions in familial recurrent depression had not been previously reported. Reduced volume of the right posterior hippocampus could be a structural endophenotype for recurrent depressive disorders in women. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  15. Echocardiographic assessment of inappropriate left ventricular mass and left ventricular hypertrophy in patients with diastolic dysfunction

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    Hasan Shemirani

    2012-01-01

    Full Text Available Background: early diagnosis of left ventricular mass (LVM inappropriateness and left ventricular hypertrophy (LVH can result in preventing diastolic left ventricular dysfunction and its related morbidity and mortality. This study was performed to determine if diastolic dysfunction is associated with LVH and inappropriate LVM. Materials and Methods: one hundred and twenty five uncomplicated hypertension from Isfahan Healthy Heart Program underwent two-dimensional echocardiography. Inappropriate LVM was defined as an LVM index greater than 88 g/m2 of body-surface area in women and greater than 102 g/m2 in men. LVH-defined septal and posterior wall thickness greater than 0/9 cm in women and greater than 1 cm in men, respectively. Echocardiographic parameters, including early diastolic peak velocity (E/late diastolic peak velocity (A, deceleration time (DT, and E/early mitral annulus velocity (E′ were measured. Results: the mean systolic and diastolic blood pressure at the patients′ admission day were 142.87 ± 18.12 and 88.45 ± 9.18 mmHg, respectively. Totally, 21.7% of subjects had inappropriate LV mass that moderate and severe abnormal LV mass was revealed in 5.6% and 5.6%, respectively. The mean of age and BMI was significantly higher in patients with moderate left ventricular hypertrophy (P 0.05. Spearman′s Rank test was used to test the correlation between diastolic dysfunction and LV mass (P = 0.025. Conclusion: LVH is correlated with the severity of diastolic dysfunction manifested by the E/A value and deceleration time, but inappropriate LVM can slightly predict diastolic dysfunction severity in uncomplicated hypertension.

  16. Transcatheter closure of large atrial septal defects with deficient aortic or posterior rims using the "Greek maneuver". A multicenter study.

    Science.gov (United States)

    Thanopoulos, Basil D; Dardas, Petros; Ninios, Vlasis; Eleftherakis, Nicholaos; Karanasios, Evangelos

    2013-10-09

    We report a modification ("Greek maneuver") of the standard atrial septal defect (ASD) closure technique using the Amplatzer septal occluder (ASO) to facilitate closure of large ASDs with deficient aortic or posterior rims. 185 patients (median 10.8, range 3 to 52 years) with large ASDs (mean diameter 26±7 mm, range 20-40 mm) with a deficient aortic (134 patients) or posterior (51 patients) rim underwent catheter closure with the ASO using the "Greek maneuver" under transesophageal guidance. The Greek maneuver is applied when protrusion of the aortic edge of the deployed left disk of the device in to the right atrium is detected by echo. To circumvent this left disk is recaptured and the whole delivery system is pushed inward and leftward into the left atrium where the left disk and the 2/3 of right disk are simultaneously released. This maneuver forces the left disk to become parallel to the septum preventing the protrusion of the device into the right atrium. The ASO was successfully implanted and was associated with complete closure in 175/185 (95%) of the patients. There were no early or late complications related to the procedure during a follow-up period ranging from 6 months to 7 years. The "Greek maneuver" is a simple quite useful trick that facilitates closure of large ASDs associated with or without deficient aortic or posterior rims. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  17. Management of posterior urethral disruption injuries.

    Science.gov (United States)

    Myers, Jeremy B; McAninch, Jack W

    2009-03-01

    Posterior urethral disruption is a traumatic injury to the male urethra, which most often results from pelvic fracture. After trauma, the distraction defect between the two ends of the urethra often scars and becomes fibrotic, blocking the urethra and bladder emptying. Increasing evidence suggests that many posterior urethral disruptions occur at the junction between the membranous urethra and the bulbar urethra, which is distal to the rhabdosphincter. In the acute setting, when a posterior urethral disruption is suspected, retrograde urethrography should be performed. Posterior urethral disruptions can be managed acutely by realignment of the urethra over a urethral catheter or by placement of a suprapubic catheter for bladder drainage only. Once fibrosis has stabilized, the patient can undergo posterior urethroplasty. In most cases, this procedure can be performed via a perineal approach in a single-stage surgery. The results of this single-stage perineal urethroplasty are excellent, and a patent urethra can be re-established in the majority of men who undergo surgery.

  18. Dual origin of the left vertebral artery: extracranial MRA and CTA findings.

    LENUS (Irish Health Repository)

    Tobin, W Oliver

    2012-02-01

    A 48-year-old man presented with a posterior circulation stroke secondary to left lateral medullary infarction. Contrast-enhanced magnetic resonance angiography (CEMRA) revealed 40-45% intracranial left vertebral artery stenosis, likely atherosclerotic in nature. CEMRA and subsequent computed tomography angiography also identified a duplicate origin of the left vertebral artery. The importance of recognition of this rare anatomical variant, its potential contribution to stroke aetiology, and the advantage of non-invasive vascular imaging prior to catheter angiography is emphasised.

  19. Pars plana vitrectomy with posterior iris claw implantation for posteriorly dislocated nucleus and intraocular lens

    Directory of Open Access Journals (Sweden)

    Kishor B Patil

    2011-01-01

    Full Text Available We evaluated the safety and efficacy of pars plana vitrectomy (PPV with primary posterior iris claw intraocular lens (IOL implantation in cases of posterior dislocation of nucleus and IOL without capsular support. This was a retrospective interventional case series. Fifteen eyes underwent PPV with primary posterior iris claw IOL implantation performed by a single vitreoretinal surgeon. The main outcome measures were changes in best corrected visual acuity and anterior and posterior segment complications. A total of 15 eyes were included in this study. Eight had nucleus drop, three had IOL drop during cataract surgery and four had traumatic posterior dislocation of lens. The final postoperative best corrected visual acuity was 20/60 or better in 11 patients. This procedure is a viable option in achieving good functional visual acuity in eyes without capsular support.

  20. Late presentation of posterior urethral valves.

    Science.gov (United States)

    Jalbani, Imran Khan; Biyabani, Syed Raziuddin

    2014-05-01

    Presence of posterior urethral valves (PUV) is the most common cause of urinary tract obstruction in the male neonate. Late presentation occurs in 10% of cases. We present a case of PUVs in an adult male who presented with history of obstructive lower urinary tract symptoms and hematuria. On evaluation, he was found to have raised serum creatinine level. A voiding cystourethrogram (VCUG) could not be completely performed because of narrowing in the posterior urethra. A rigid urethrocystoscopy was performed at which he was found to have type-I posterior urethral valve which were fulgurated. A repeat uroflowmetry revealed maximum flow rate of 12 ml/second. This case highlights that PUVs is not solely a disease of infancy but may also present late. VCUG is the radiological investigation of choice but the diagnosis may be missed. A urethrocystoscopy is advised if there is a high index of suspicion.

  1. MANAGEMENT OF POSTERIOR DISLOCATED INTRAOCULAR LENSES IN A TERTIARY HOSPITAL

    Directory of Open Access Journals (Sweden)

    Shashidhar

    2016-10-01

    Full Text Available BACKGROUND The aim of this study was to assess and compare the visual outcome of different approaches in the management of dislocated PCIOL. MATERIALS AND METHODS 20 eyes of 20 patients who underwent 3PPPV/anterior vitrectomy to refixate or IOL exchange for dislocation or subluxation of PCIOL from 2012 to 2015. SFIOLs were implanted in 12 patients, IOL refixation was done in four patients and four were left aphakic. This is a retrospective study of 20 eyes of 20 patients with dislocated/subluxated PCIOLs in a tertiary hospital from 2012 to 2015. STATISTICAL ANALYSIS Paired t-test statistical method. RESULTS We retrospectively analysed hospital records of patients who had undergone three PPPV/anterior vitrectomy for posteriorly dislocated/subluxated IOLs 20 eyes of 20 patients were analysed. SFIOLs were implanted in 12 patients, IOL refixation was done in four patients and four were left aphakic. Postoperative BCVA of 6/12 or better was achieved in 66.67% in primary SFIOL, secondary SFIOL and IOL refixation groups. BCVA of <6/60 was seen in all patients left aphakic. Early and late complications were most in aphakic patients. IOL refixation procedure had minimum early and late complications. Subluxated PCIOLs do better than dislocated lens where a successful SFIOL was placed. CONCLUSION IOL refixation procedure has the least complication rate. Early complications of SFIOL management resolve with time. Thus, 3PPPV/anterior vitrectomy with SFIOL and IOL refixation procedures offer a novel approach towards visual rehabilitation of patients with subluxated or dislocated PCIOLs.

  2. MORPHOLOGICAL CHANGES IN THE HIPPOCAMPUS OF RATS IN ACCELERATED AGING

    Directory of Open Access Journals (Sweden)

    K. Yu. Maksimova

    2014-01-01

    Full Text Available The aim of this work was the analysis of structural changes with age in the hippocampus of senescenceaccelerated OXYS rats when signs of accelerated brain aging are missing (age 14 days, developments (age 5 months, and active progresses (age 15 months. The study was performed on 15 OXYS rats and 15 Wistar rats (as a control. After dislocation, brains were dissected, fixed with 10% formalin, embedded in paraffin, and serially cut in coronal sections (5μm thickness. These sections were stained with Cresyl violet and examined with a photomicroscope (Carl Zeiss Axiostar plus, Germany. The total number of hippocampal pyramidal cells in the CA1, CA3 and the dentate gyrus regions were estimated in 14-dayold, 5and 15-month-old OXYS and Wistar rats (n = 5 on the 5 slices of each brain sections. The number of neurons with chromatolysis, hyperchromatic with darkly stained cytoplasm and shrunken neurons were calculated as degenerative neurons. The pictures obtained with the program Carl Zeiss Axio Vision 8.0 with increasing 10  100, determined the average area bodies and nuclei of neurons (mkm2. The significant structural changes of neurons in the CA1, CA3 and dentate gyrus regions of the hippocampus in OXYS rats at 5 month of age are revealed by light microscopy. This results indicates the early develop neurodegeneration in OXYS rats. The most pronounced morphological changes occur in the CA1 region of the hippocampus of OXYS rats and irreversible. The degenerative changes of neurons in the hippocampus increases by the age of 15 months. Morphometric analysis of the average area of bodies and the nuclei of hippocampal neurons in CA1, CA3 and the dentate gyrus regions of OXYS and Wistar rats at 14 days of age showed no significant interline differences. At 5 months of age in the CA1 region of the hippocampus of OXYS rats was determined a significantly lower average body size and nuclei of pyramidal neurons compared with Wistar rats. With age, these

  3. 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.

  4. Posterior predictive checking of multiple imputation models.

    Science.gov (United States)

    Nguyen, Cattram D; Lee, Katherine J; Carlin, John B

    2015-07-01

    Multiple imputation is gaining popularity as a strategy for handling missing data, but there is a scarcity of tools for checking imputation models, a critical step in model fitting. Posterior predictive checking (PPC) has been recommended as an imputation diagnostic. PPC involves simulating "replicated" data from the posterior predictive distribution of the model under scrutiny. Model fit is assessed by examining whether the analysis from the observed data appears typical of results obtained from the replicates produced by the model. A proposed diagnostic measure is the posterior predictive "p-value", an extreme value of which (i.e., a value close to 0 or 1) suggests a misfit between the model and the data. The aim of this study was to evaluate the performance of the posterior predictive p-value as an imputation diagnostic. Using simulation methods, we deliberately misspecified imputation models to determine whether posterior predictive p-values were effective in identifying these problems. When estimating the regression parameter of interest, we found that more extreme p-values were associated with poorer imputation model performance, although the results highlighted that traditional thresholds for classical p-values do not apply in this context. A shortcoming of the PPC method was its reduced ability to detect misspecified models with increasing amounts of missing data. Despite the limitations of posterior predictive p-values, they appear to have a valuable place in the imputer's toolkit. In addition to automated checking using p-values, we recommend imputers perform graphical checks and examine other summaries of the test quantity distribution. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Posterior muscolofascial reconstruction incorporated into urethrovescical anastomosis during robot-assisted radical prostatectomy.

    Science.gov (United States)

    Ficarra, Vincenzo; Gan, Melanie; Borghesi, Marco; Zattoni, Fabio; Mottrie, Alexandre

    2012-12-01

    The rationale of posterior musculofascial plate reconstruction during radical prostatectomy is to shorten the time to reach urinary continence recovery and to reduce the risk of bleeding and anastomosis leakage. We describe our original technique incorporating the posterior muscolofascial reconstruction into urethrovesical anastomosis using robot-assisted radical prostatectomy (RARP). For this reconstructive step, we use a 30-cm V-Loc 90 3-0 barbed suture (V-20 tapered needle). Specifically, the free edge of the posterior layer of the Denonvilliers fascia is approximated to the posterior part of the sphincteric apparatus in a running fashion from left to right. The musculature of the urethral wall is incorporated in this first layer of the running suture. This suture is then continued back to the left in a second layer incorporating the anterior layer of the Denonvilliers fascia (or prostatovesical muscle), the bladder neck, and again the urethra, this time also with urethral mucosa. The urethrovesical anastomosis is completed using a second running barbed suture (15-cm V-Loc 90 3-0 barbed suture, V-20 tapered needle). No intraoperative complications were observed during this step of the procedure. Anastomotic leakages were observed only in 2% of cases. Only 12.5% showed urinary incontinence after catheter removal (1-2 pads). At mean follow-up of 9 months, the urinary continence recovery was 95%, and an anastomosis stricture necessitating an endoscopic incision developed in only three (1.5%) patients. Recent systematic reviews of the literature showed only a minimal advantage in favor of posterior musculofascial reconstruction in terms of urinary continence recovery within 1 month after radical prostatectomy. We support the use of this step of RARP because it is simple, reproducible, with a very limited increase in operative time, and with only a slight risk of potential harm to the patient. Moreover, it could improve hemostasis and provide greater support for a

  6. Superior Temporal Gyrus Volume Abnormalities and Thought Disorder in Left-Handed Schizophrenic Men

    Science.gov (United States)

    Holinger, Dorothy P.; Shenton, Martha E.; Wible, Cynthia G.; Donnino, Robert; Kikinis, Ron; Jolesz, Ferenc A.; McCarley, Robert W.

    2010-01-01

    Objective Studies of schizophrenia have not clearly defined handedness as a differentiating variable. Moreover, the relationship between thought disorder and anatomical anomalies has not been studied extensively in left-handed schizophrenic men. The twofold purpose of this study was to investigate gray matter volumes in the superior temporal gyrus of the temporal lobe (left and right hemispheres) in left-handed schizophrenic men and left-handed comparison men, in order to determine whether thought disorder in the left-handed schizophrenic men correlated with tissue volume abnormalities. Method Left-handed male patients (N=8) with DSM-III-R diagnoses of schizophrenia were compared with left-handed comparison men (N=10) matched for age, socioeconomic status, and IQ. Magnetic resonance imaging (MRI) with a 1.5-T magnet was used to obtain scans, which consisted of contiguous 1.5-mm slices of the whole brain. MRI analyses (as previously defined by the authors) included the anterior, posterior, and total superior temporal gyrus in both the left and right hemispheres. Results There were three significant findings regarding the left-handed schizophrenic men: 1) bilaterally smaller gray matter volumes in the posterior superior temporal gyrus (16% smaller on the right, 15% smaller on the left); 2) a smaller volume on the right side of the total superior temporal gyrus; and 3) a positive correlation between thought disorder and tissue volume in the right anterior superior temporal gyrus. Conclusions These results suggest that expression of brain pathology differs between left-handed and right-handed schizophrenic men and that the pathology is related to cognitive disturbance. PMID:10553736

  7. Transverse posterior element fractures associated with torsion

    International Nuclear Information System (INIS)

    Abel, M.S.

    1989-01-01

    Six examples of a previously undescribed class of transverse vertebral element fractures are presented. These fractures differ from Chance and Smith fractures and their variants in the following respects: (1) the etiology is torsion and not flexion; (2) there is neither distraction of posterior ring fragments nor posterior ligament tears; (3) in contrast to Chance and Smith fractures, extension of the fracture into the vertebral body is absent or minimal; (4) the transverse process of the lumbar vertebra is avulsed at its base with a vertical fracture, not split horizontally. These fractures occur in cervical, lumbar, and sacral vertebrae in normal or compromised areas of the spine. (orig.)

  8. Posterior sternoclavicular dislocation: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, So Hwa; Kim, Ki Sun; Kim, Ki Jun [Dept. of Radiology, Incheon St. Mary' s Hospital, The Catholic University of Korea College of Medicine, Incheon (Korea, Republic of)

    2015-02-15

    Traumatic sternoclavicular joint dislocation is an uncommon injury, and posterior sternoclavicular dislocation occurs less frequently compared to anterior sternoclavicular dislocation. However, this type of dislocation has the potential for serious complications due to compression or laceration of the mediastinal structures. The diagnosis can be difficult using plain radiographs alone due to radiographic-anatomic superimposition. Therefore, posterior sternoclavicular dislocation is easily missed at the initial clinical evaluation. Contrast-enhanced computed tomography is required for a definite diagnosis and to assess associated mediastinal injuries.

  9. Posterior leukoencephalopathy syndrome in poststretococcal acute glomerulonephritis

    International Nuclear Information System (INIS)

    Bazzino Borzone, F.; Pandolfo Arias, M.; Protasio Palomino, L.; Pujadas Ferrer, M.; Cerisola Cardozo, A.; Gonzalez, G.; Caggiani Malzone, M.; Rubio Santoro, I.

    2005-01-01

    Reversible posterior leukoencephalopathy (LEPR) is a clinical entity that affects radiation usually the white matter of the cerebral hemispheres. It is frequently associated with acute arterial hypertension and immunosuppressive therapy, among other causes. The clinical presentation is varied, with headache, nausea, vomiting, impaired consciousness and abnormal behavior, seizures and visual disturbances, symptoms that often regress. Computed tomography (CT) and magnetic resonance imaging (MRI) images show white matter edema predominantly in posterior regions of the brain. We present a 10 year old boy with leprosy in the course of a nephrotic syndrome secondary to acute diffuse glomerunefritis (GNDA) poststreptococcal. (author) [es

  10. [Significance of early diagnosis of posterior urethral valves in fetus for further development - own experience].

    Science.gov (United States)

    Krzemień, Grażyna; Szmigielska, Agnieszka; Wawer, Zofia; Roszkowska-Blaim, Maria

    2013-01-01

    The incidence of posterior urethral valves is estimated to be from 3:1000 to 8:1000 and this is one of the most common causes of obstruction of urinary tract in boys. About 13-17% of children with posterior urethral valves develop end stage renal failure. We present a  6-month-old boy with late diagnosis of posterior urtehral valves. Antenatal ultrasound investigation of the urinary tract was normal. A small degree of oligohydramnios was found during delivery. At the age of six months the boy was admitted to hospital because of urinary tract infection, hypertension (130/90 mmHg) and acute kidney injury (urea - 46 mg/dL, creatinine - 1.1 mg/dL, GFR - 35.5 mL/min/1.73 m2 ). Bilateral hydronephrosis and megaureters, low-capacity bladder with hypertrophied wall were seen on ultrasound examination. Voiding cystourethrograhy revealed vesicoureteral refluxes (III/V), hypertrophy of the bladder wall with numerous diverticula and dilated posterior urethra. During urethroscopy urethral valves were resected. Increased intravesical pressure (leak point up to 305 cm H2 O) was found on urodynamic test. Renal scintigraphy (99mTc-EC) revealed decreased intake of isotope in the left kidney (5%), and the right kidney intake was 95% ERPF. The patient was qualified for left-sided nephrectomy, which was postponed because of high leak point and high risk of worsening of vesicoureteral reflux to right kidney after nephrectomy. Anticholinergic and α-blocker treatment was started. At the age of 11 months left-side nephrectomy was performed because of recurrent urinary tract infections. After 3.5-year follow-up blood pressure, physical development, kidney function tests, and urinalysis are normal. Additionally to this investigation the significance of early diagnosis including prenatal (PUV) for further development as well as further therapeutic procedure is discussed.

  11. Myxoma of the Left Ventricle

    Science.gov (United States)

    Novoa, José; Delgado, Antonio; Alonso, Ana

    2014-01-01

    This report concerns a 69-year-old woman who presented with an asymptomatic myxoma in the left ventricle. The tumor was successfully excised. We provide a very brief review of 72 other published cases of surgically treated left ventricular myxoma. PMID:25120392

  12. The Left-Handed Writer.

    Science.gov (United States)

    Bloodsworth, James Gaston

    Contrary to the beliefs of many, right-handedness is not a single factor existing in almost all people, with a few exceptions termed left-handed: neither extreme exists independently of the other. During the first 4 years of life there is a period of fluctuation between right and left-handed dominance. Statistics and findings vary in determining…

  13. Two Lefts in Latin America?

    DEFF Research Database (Denmark)

    Christensen, Steen Fryba

    In this working paper I list five researchers' categorizations of the Latin American left in power (april 2006) in a schematic form. The most important criteria for the categorizations are given.......In this working paper I list five researchers' categorizations of the Latin American left in power (april 2006) in a schematic form. The most important criteria for the categorizations are given....

  14. A Giant Left Atrial Myxoma

    Directory of Open Access Journals (Sweden)

    Medhat F. Zaher

    2014-01-01

    Full Text Available Atrial myxomas are the most common primary cardiac tumors. Patients with left atrial myxomas generally present with mechanical obstruction of blood flow, systemic embolization, and constitutional symptoms. We present a case of an unusually large left atrial myxoma discovered incidentally in a patient with longstanding dyspnea being managed as bronchial asthma.

  15. Ideomotor Apraxia in Left Thalamic Hemorrhage: Discrepancy between Clinical Course and SPECT

    Directory of Open Access Journals (Sweden)

    Armin Schnider

    1991-01-01

    Full Text Available We present a patient who developed severe ideomotor apraxia (IA and subcortical aphasia after a hemorrhage involving the posterior part of the left thalamus and the posterior limb of the internal capsule. The cerebral blood flow (CBF of the left hemisphere as measured by 99Tc-HM-PAO SPECT was initially diminished as compared to the right hemisphere. The apraxia and aphasia eventually resolved. Despite this clinical improvement CBF of the left hemisphere worsened. Our findings do not support the view that apraxia and aphasia following lesion of deep subcortical structures is due to cortical derangement induced by disruption of unspecific activating thalamo-cortical pathways. The results call for caution in the functional interpretation of perfusion deficits detected by SPECT.

  16. Fetal Stomach Position Predicts Neonatal Outcomes in Isolated Left-Sided Congenital Diaphragmatic Hernia.

    Science.gov (United States)

    Basta, Amaya M; Lusk, Leslie A; Keller, Roberta L; Filly, Roy A

    2016-01-01

    We sought to determine the relationship between the degree of stomach herniation by antenatal sonography and neonatal outcomes in fetuses with isolated left-sided congenital diaphragmatic hernia (CDH). We retrospectively reviewed neonatal medical records and antenatal sonography of fetuses with isolated left CDH cared for at a single institution (2000-2012). Fetal stomach position was classified on sonography as follows: intra-abdominal, anterior left chest, mid-to-posterior left chest, or retrocardiac (right chest). Ninety fetuses were included with 70% surviving to neonatal discharge. Stomach position was intra-abdominal in 14% (n = 13), anterior left chest in 19% (n = 17), mid-to-posterior left chest in 41% (n = 37), and retrocardiac in 26% (n = 23). Increasingly abnormal stomach position was linearly associated with an increased odds of death (OR 4.8, 95% CI 2.1-10.9), extracorporeal membrane oxygenation (ECMO; OR 5.6, 95% CI 1.9-16.7), nonprimary diaphragmatic repair (OR 2.7, 95% CI 1.4-5.5), prolonged mechanical ventilation (OR 5.9, 95% CI 2.3-15.6), and prolonged respiratory support (OR 4.0, 95% CI 1.6-9.9). All fetuses with intra-abdominal stomach position survived without substantial respiratory morbidity or need for ECMO. Fetal stomach position is strongly associated with neonatal outcomes in isolated left CDH. This objective tool may allow for accurate prognostication in a variety of clinical settings. © 2015 S. Karger AG, Basel.

  17. The effect of hippocampal function, volume and connectivity on posterior cingulate cortex functioning during episodic memory fMRI in mild cognitive impairment

    Energy Technology Data Exchange (ETDEWEB)

    Papma, Janne M.; Koudstaal, Peter J.; Swieten, John C. van [Erasmus MC - University Medical Center Rotterdam, Department of Neurology, Rotterdam (Netherlands); Smits, Marion; Lugt, Aad van der [Erasmus MC - University Medical Center Rotterdam, Department of Radiology, Rotterdam (Netherlands); Groot, Marius de; Vrooman, Henri A. [Erasmus MC - University Medical Center Rotterdam, Department of Radiology, Rotterdam (Netherlands); Erasmus MC - University Medical Center Rotterdam, Department of Medical Informatics, Rotterdam (Netherlands); Mattace Raso, Francesco U. [Erasmus MC - University Medical Center Rotterdam, Department of Geriatrics, Rotterdam (Netherlands); Niessen, Wiro J. [Erasmus MC - University Medical Center Rotterdam, Department of Radiology, Rotterdam (Netherlands); Erasmus MC - University Medical Center Rotterdam, Department of Medical Informatics, Rotterdam (Netherlands); Delft University of Technology, Faculty of Applied Sciences, Delft (Netherlands); Veen, Frederik M. van der [Erasmus University Rotterdam, Institute of Psychology, Rotterdam (Netherlands); Prins, Niels D. [VU University Medical Center, Alzheimer Center, Department of Neurology, Amsterdam (Netherlands)

    2017-09-15

    Diminished function of the posterior cingulate cortex (PCC) is a typical finding in early Alzheimer's disease (AD). It is hypothesized that in early stage AD, PCC functioning relates to or reflects hippocampal dysfunction or atrophy. The aim of this study was to examine the relationship between hippocampus function, volume and structural connectivity, and PCC activation during an episodic memory task-related fMRI study in mild cognitive impairment (MCI). MCI patients (n = 27) underwent episodic memory task-related fMRI, 3D-T1w MRI, 2D T2-FLAIR MRI and diffusion tensor imaging. Stepwise linear regression analysis was performed to examine the relationship between PCC activation and hippocampal activation, hippocampal volume and diffusion measures within the cingulum along the hippocampus. We found a significant relationship between PCC and hippocampus activation during successful episodic memory encoding and correct recognition in MCI patients. We found no relationship between the PCC and structural hippocampal predictors. Our results indicate a relationship between PCC and hippocampus activation during episodic memory engagement in MCI. This may suggest that during episodic memory, functional network deterioration is the most important predictor of PCC functioning in MCI. (orig.)

  18. The effect of hippocampal function, volume and connectivity on posterior cingulate cortex functioning during episodic memory fMRI in mild cognitive impairment

    International Nuclear Information System (INIS)

    Papma, Janne M.; Koudstaal, Peter J.; Swieten, John C. van; Smits, Marion; Lugt, Aad van der; Groot, Marius de; Vrooman, Henri A.; Mattace Raso, Francesco U.; Niessen, Wiro J.; Veen, Frederik M. van der; Prins, Niels D.

    2017-01-01

    Diminished function of the posterior cingulate cortex (PCC) is a typical finding in early Alzheimer's disease (AD). It is hypothesized that in early stage AD, PCC functioning relates to or reflects hippocampal dysfunction or atrophy. The aim of this study was to examine the relationship between hippocampus function, volume and structural connectivity, and PCC activation during an episodic memory task-related fMRI study in mild cognitive impairment (MCI). MCI patients (n = 27) underwent episodic memory task-related fMRI, 3D-T1w MRI, 2D T2-FLAIR MRI and diffusion tensor imaging. Stepwise linear regression analysis was performed to examine the relationship between PCC activation and hippocampal activation, hippocampal volume and diffusion measures within the cingulum along the hippocampus. We found a significant relationship between PCC and hippocampus activation during successful episodic memory encoding and correct recognition in MCI patients. We found no relationship between the PCC and structural hippocampal predictors. Our results indicate a relationship between PCC and hippocampus activation during episodic memory engagement in MCI. This may suggest that during episodic memory, functional network deterioration is the most important predictor of PCC functioning in MCI. (orig.)

  19. The effect of hippocampal function, volume and connectivity on posterior cingulate cortex functioning during episodic memory fMRI in mild cognitive impairment.

    Science.gov (United States)

    Papma, Janne M; Smits, Marion; de Groot, Marius; Mattace Raso, Francesco U; van der Lugt, Aad; Vrooman, Henri A; Niessen, Wiro J; Koudstaal, Peter J; van Swieten, John C; van der Veen, Frederik M; Prins, Niels D

    2017-09-01

    Diminished function of the posterior cingulate cortex (PCC) is a typical finding in early Alzheimer's disease (AD). It is hypothesized that in early stage AD, PCC functioning relates to or reflects hippocampal dysfunction or atrophy. The aim of this study was to examine the relationship between hippocampus function, volume and structural connectivity, and PCC activation during an episodic memory task-related fMRI study in mild cognitive impairment (MCI). MCI patients (n = 27) underwent episodic memory task-related fMRI, 3D-T1w MRI, 2D T2-FLAIR MRI and diffusion tensor imaging. Stepwise linear regression analysis was performed to examine the relationship between PCC activation and hippocampal activation, hippocampal volume and diffusion measures within the cingulum along the hippocampus. We found a significant relationship between PCC and hippocampus activation during successful episodic memory encoding and correct recognition in MCI patients. We found no relationship between the PCC and structural hippocampal predictors. Our results indicate a relationship between PCC and hippocampus activation during episodic memory engagement in MCI. This may suggest that during episodic memory, functional network deterioration is the most important predictor of PCC functioning in MCI. • PCC functioning during episodic memory relates to hippocampal functioning in MCI. • PCC functioning during episodic memory does not relate to hippocampal structure in MCI. • Functional network changes are an important predictor of PCC functioning in MCI.

  20. Left-handedness and health

    Directory of Open Access Journals (Sweden)

    Milenković Sanja

    2010-01-01

    Full Text Available Hand dominance is defined as a proneness to use one hand rather than another in performing the majority of activities and this is the most obvious example of cerebral lateralization and an exclusive human characteristic. Left-handed people comprise 6-14% of the total population, while in Serbia, this percentage is 5-10%, moving from undeveloped to developed environments, where a socio-cultural pressure is less present. There is no agreement between investigators who in fact may be considered a left-handed person, about the percentage of left-handers in the population and about the etiology of left-handedness. In the scientific literature left-handedness has been related to health disorders (spine deformities, immunological disorders, migraine, neurosis, depressive psychosis, schizophrenia, insomnia, homosexuality, diabetes mellitus, arterial hypertension, sleep apnea, enuresis nocturna and Down Syndrome, developmental disorders (autism, dislexia and sttutering and traumatism. The most reliable scientific evidences have been published about the relationship between left-handedness and spinal deformities in school children in puberty and with traumatism in general population. The controversy of other results in up-to-now investigations of health aspects of left-handedness may partly be explained by a scientific disagreement whether writing with the left hand is a sufficient criterium for left-handedness, or is it necessary to investigate other parameters for laterality assessment. Explanation of health aspects of left-handedness is dominantly based on Geschwind-Galaburda model about 'anomalous' cerebral domination, as a consequence of hormonal disbalance. .

  1. Left ventricular wall stress compendium.

    Science.gov (United States)

    Zhong, L; Ghista, D N; Tan, R S

    2012-01-01

    Left ventricular (LV) wall stress has intrigued scientists and cardiologists since the time of Lame and Laplace in 1800s. The left ventricle is an intriguing organ structure, whose intrinsic design enables it to fill and contract. The development of wall stress is intriguing to cardiologists and biomedical engineers. The role of left ventricle wall stress in cardiac perfusion and pumping as well as in cardiac pathophysiology is a relatively unexplored phenomenon. But even for us to assess this role, we first need accurate determination of in vivo wall stress. However, at this point, 150 years after Lame estimated left ventricle wall stress using the elasticity theory, we are still in the exploratory stage of (i) developing left ventricle models that properly represent left ventricle anatomy and physiology and (ii) obtaining data on left ventricle dynamics. In this paper, we are responding to the need for a comprehensive survey of left ventricle wall stress models, their mechanics, stress computation and results. We have provided herein a compendium of major type of wall stress models: thin-wall models based on the Laplace law, thick-wall shell models, elasticity theory model, thick-wall large deformation models and finite element models. We have compared the mean stress values of these models as well as the variation of stress across the wall. All of the thin-wall and thick-wall shell models are based on idealised ellipsoidal and spherical geometries. However, the elasticity model's shape can vary through the cycle, to simulate the more ellipsoidal shape of the left ventricle in the systolic phase. The finite element models have more representative geometries, but are generally based on animal data, which limits their medical relevance. This paper can enable readers to obtain a comprehensive perspective of left ventricle wall stress models, of how to employ them to determine wall stresses, and be cognizant of the assumptions involved in the use of specific models.

  2. Nicotinic mechanisms influencing synaptic plasticity in the hippocampus

    Science.gov (United States)

    Placzek, Andon Nicholas; Zhang, Tao A; Dani, John Anthony

    2009-01-01

    Nicotinic acetylcholine receptors (nAChRs) are expressed throughout the hippocampus, and nicotinic signaling plays an important role in neuronal function. In the context of learning and memory related behaviors associated with hippocampal function, a potentially significant feature of nAChR activity is the impact it has on synaptic plasticity. Synaptic plasticity in hippocampal neurons has long been considered a contributing cellular mechanism of learning and memory. These same kinds of cellular mechanisms are a factor in the development of nicotine addiction. Nicotinic signaling has been demonstrated by in vitro studies to affect synaptic plasticity in hippocampal neurons via multiple steps, and the signaling has also been shown to evoke synaptic plasticity in vivo. This review focuses on the nAChRs subtypes that contribute to hippocampal synaptic plasticity at the cellular and circuit level. It also considers nicotinic influences over long-term changes in the hippocampus that may contribute to addiction. PMID:19434057

  3. MOLECULAR BASIS OF LEARNING IN THE HIPPOCAMPUS AND THE AMYGDALA

    Directory of Open Access Journals (Sweden)

    Łukasz BIJOCH

    2015-12-01

    Full Text Available The hippocampus and the amygdala are structures of mammalian brain both involved in memorizing. However, they are responsible for different types of memory: the hippocampus is involved in creating and storing declarative engrams and the amygdala is engaged in some of non-declarative learning. During memorization, changes of synapses appear and it is believed that they encode information. Long-Term Potentiation (LTP and Long-Term Depression (LTD are two processes which provide to these changes which are called synaptic plasticity. LTP strengthens connections between neurons and because of that it is traditionally linked with learning. LTD as an opposite state is usually treated as forgetting. However, there are some evidences that it is true only for few types of non-declarative engrams. More sophisticated learning (like declarative learning requires cooperation of these processes. Review is focused on functions and detailed signaling pathways of processes of synaptic plasticity.

  4. Nitric Oxide Regulates Neurogenesis in the Hippocampus following Seizures

    Directory of Open Access Journals (Sweden)

    Bruno P. Carreira

    2015-01-01

    Full Text Available Hippocampal neurogenesis is changed by brain injury. When neuroinflammation accompanies injury, activation of resident microglial cells promotes the release of inflammatory cytokines and reactive oxygen/nitrogen species like nitric oxide (NO. In these conditions, NO promotes proliferation of neural stem cells (NSC in the hippocampus. However, little is known about the role of NO in the survival and differentiation of newborn cells in the injured dentate gyrus. Here we investigated the role of NO following seizures in the regulation of proliferation, migration, differentiation, and survival of NSC in the hippocampus using the kainic acid (KA induced seizure mouse model. We show that NO increased the proliferation of NSC and the number of neuroblasts following seizures but was detrimental to the survival of newborn neurons. NO was also required for the maintenance of long-term neuroinflammation. Taken together, our data show that NO positively contributes to the initial stages of neurogenesis following seizures but compromises survival of newborn neurons.

  5. Hippocampus sparing in whole-brain radiotherapy. A review

    International Nuclear Information System (INIS)

    Oskan, F.; Ganswindt, U.; Schwarz, S.B.; Manapov, F.; Belka, C.; Niyazi, M.

    2014-01-01

    Radiation treatment techniques for whole-brain radiation therapy (WBRT) have not changed significantly since development of the procedure. However, the recent development of novel techniques such as intensity-modulated radiation therapy (IMRT), volumetric-modulated arc therapy (VMAT) and helical tomotherapy, as well as an increasing body of evidence concerning neural stem cells (NSCs) have altered the conventional WBRT treatment paradigm. In this regard, hippocampus-sparing WBRT is a novel technique that aims to spare critical hippocampus regions without compromising tumour control. Published data on this new technique are limited to planning and feasibility studies; data on patient outcome are still lacking. However, several prospective trials to analyse the feasibility of this technique and to document clinical outcome in terms of reduced neurotoxicity are ongoing. (orig.) [de

  6. Induction of motor associative plasticity in the posterior parietal cortex-primary motor network

    DEFF Research Database (Denmark)

    Chao, Chi-Chao; Karabanov, Anke Ninija; Paine, Rainer

    2015-01-01

    There is anatomical and functional connectivity between the primary motor cortex (M1) and posterior parietal cortex (PPC) that plays a role in sensorimotor integration. In this study, we applied corticocortical paired-associative stimuli to ipsilateral PPC and M1 (parietal ccPAS) in healthy right...... the excitability of conditioned left M1 assessed by motor evoked potentials (MEPs) and the input–output curve. Motor behavior assessed by the Purdue pegboard task was unchanged compared with controls. At baseline, conditioning stimuli over the left PPC potentiated MEPs from left M1 when ISI was 8 ms...... excitability and PPC–M1 connectivity and is a new approach to modify motor excitability and sensorimotor interaction....

  7. Caffeine alters proliferation of neuronal precursors in the adult hippocampus

    OpenAIRE

    Wentz, Christian T.; Magavi, Sanjay S.P.

    2009-01-01

    Neurogenesis continues through adulthood in the hippocampus and olfactory bulb of mammals. Adult neurogenesis has been implicated in learning and memory, and linked with depression. Hippocampal neurogenesis is increased in response to a number of stimuli, including exposure to an enriched environment, increased locomotor activity, and administration of antidepressants. Adult neurogenesis is depressed in response to aging, stress and sleep deprivation. Intriguingly, caffeine modulates a number...

  8. Gene expression in cortex and hippocampus during acute pneumococcal meningitis

    Directory of Open Access Journals (Sweden)

    Wittwer Matthias

    2006-06-01

    Full Text Available Abstract Background Pneumococcal meningitis is associated with high mortality (~30% and morbidity. Up to 50% of survivors are affected by neurological sequelae due to a wide spectrum of brain injury mainly affecting the cortex and hippocampus. Despite this significant disease burden, the genetic program that regulates the host response leading to brain damage as a consequence of bacterial meningitis is largely unknown. We used an infant rat model of pneumococcal meningitis to assess gene expression profiles in cortex and hippocampus at 22 and 44 hours after infection and in controls at 22 h after mock-infection with saline. To analyze the biological significance of the data generated by Affymetrix DNA microarrays, a bioinformatics pipeline was used combining (i a literature-profiling algorithm to cluster genes based on the vocabulary of abstracts indexed in MEDLINE (NCBI and (ii the self-organizing map (SOM, a clustering technique based on covariance in gene expression kinetics. Results Among 598 genes differentially regulated (change factor ≥ 1.5; p ≤ 0.05, 77% were automatically assigned to one of 11 functional groups with 94% accuracy. SOM disclosed six patterns of expression kinetics. Genes associated with growth control/neuroplasticity, signal transduction, cell death/survival, cytoskeleton, and immunity were generally upregulated. In contrast, genes related to neurotransmission and lipid metabolism were transiently downregulated on the whole. The majority of the genes associated with ionic homeostasis, neurotransmission, signal transduction and lipid metabolism were differentially regulated specifically in the hippocampus. Of the cell death/survival genes found to be continuously upregulated only in hippocampus, the majority are pro-apoptotic, while those continuously upregulated only in cortex are anti-apoptotic. Conclusion Temporal and spatial analysis of gene expression in experimental pneumococcal meningitis identified potential

  9. Sleep in the human hippocampus: a stereo-EEG study.

    Directory of Open Access Journals (Sweden)

    Fabio Moroni

    Full Text Available BACKGROUND: There is compelling evidence indicating that sleep plays a crucial role in the consolidation of new declarative, hippocampus-dependent memories. Given the increasing interest in the spatiotemporal relationships between cortical and hippocampal activity during sleep, this study aimed to shed more light on the basic features of human sleep in the hippocampus. METHODOLOGY/PRINCIPAL FINDINGS: We recorded intracerebral stereo-EEG directly from the hippocampus and neocortical sites in five epileptic patients undergoing presurgical evaluations. The time course of classical EEG frequency bands during the first three NREM-REM sleep cycles of the night was evaluated. We found that delta power shows, also in the hippocampus, the progressive decrease across sleep cycles, indicating that a form of homeostatic regulation of delta activity is present also in this subcortical structure. Hippocampal sleep was also characterized by: i a lower relative power in the slow oscillation range during NREM sleep compared to the scalp EEG; ii a flattening of the time course of the very low frequencies (up to 1 Hz across sleep cycles, with relatively high levels of power even during REM sleep; iii a decrease of power in the beta band during REM sleep, at odds with the typical increase of power in the cortical recordings. CONCLUSIONS/SIGNIFICANCE: Our data imply that cortical slow oscillation is attenuated in the hippocampal structures during NREM sleep. The most peculiar feature of hippocampal sleep is the increased synchronization of the EEG rhythms during REM periods. This state of resonance may have a supportive role for the processing/consolidation of memory.

  10. Receptor autoradiography in the hippocampus of man and rat

    International Nuclear Information System (INIS)

    Zilles, K.

    1988-01-01

    This chapter deals with the following questions: regional distribution of binding sites for 5-HT, glutamate, and acetylcholine in Ammon's horn and the dentate gyrus of rat and human brain; comparison of receptor distribution and neuronal pathways with identified transmitters; correlation of region-specific densities between different receptors and receptor subtypes (colocalization of different receptors on the level of hippocampal layers) and comparison of receptor distribution in human and rat hippocampus

  11. Visual cortex plasticity evokes excitatory alterations in the hippocampus

    Directory of Open Access Journals (Sweden)

    Marian Tsanov

    2009-11-01

    Full Text Available The integration of episodic sequences in the hippocampus is believed to occur during theta rhythm episodes, when cortico-hippocampal dialog results in reconfiguration of neuronal assemblies. As the visual cortex (VC is a major source of sensory information to the hippocampus, information processing in the cortex may affect hippocampal network oscillations, facilitating the induction of synaptic modifications. We investigated to what degree the field activity in the primary VC, elicited by sensory or electrical stimulation, correlates with hippocampal oscillatory and synaptic responsiveness, in freely behaving adult rats. We found that the spectral power of theta rhythm (4-10Hz in the dentate gyrus (DG, increases in parallel with high-frequency oscillations in layer 2/3 of the VC and that this correlation depends on the degree of exploratory activity. When we mimic robust thalamocortical activity by theta-burst application to dorsal lateral geniculate nucleus, a hippocampal theta increase occurs, followed by a persistent potentiation of the DG granule field population spike. Furthermore, the potentiation of DG neuronal excitability tightly correlates with the concurrently occurring VC plasticity. The concurrent enhancement of VC and DG activity is also combined with a highly negative synchronization between hippocampal and cortical low frequency oscillations. Exploration of familiar environment decreases the degree of this synchrony. Our data propose that novel visual information can induce high-power fluctuations in intrinsic excitability for both VC and hippocampus, potent enough to induce experience-dependent modulation of cortico-hippocampal connections. This interaction may comprise one of the endogenous triggers for long-term synaptic plasticity in the hippocampus.

  12. Ombro flutuante associado à luxação escápulo-umeral posterior: relato de caso Floating shoulder combined with posterior scapulohumeral dislocation

    Directory of Open Access Journals (Sweden)

    Alessandro Ulhôa Rodrigues

    2007-10-01

    Full Text Available Apresenta-se rara variação de ombro flutuante associada a luxação glenoumeral posterior em paciente masculino, 26 anos de idade, vítima de acidente motociclístico. Ao exame, queixava-se de dor no ombro esquerdo, limitação dos movimentos, principalmente da rotação externa. A radiografia em ântero-posterior (AP verdadeiro mostrou fratura do colo da glenóide, sem envolvimento articular, e fratura do processo coracóide. A radiografia em perfil, axilar e a tomografia computadorizada confirmaram a luxação posterior. Os autores discutem as questões que fazem deste um caso singular no qual se optou por redução aberta e fixação da fratura com placa de reconstrução pélvica. O controle radiológico confirmou o restabelecimento da anatomia. A fratura consolidou-se, resultando em um ombro normal e funcional.A rare variation of the floating shoulder is presented, combined with a posterior glenohumeral dislocation in a male, 26 year old patient, victim of a motorcycle accident. On physical examination, he complained of pain in the left shoulder, limitation of should movements, in particular external rotation. True anteroposterior X-ray showed a fracture of the glenoid neck without joint involvement and fracture of the coracoid process. Profile, axillary X-ray and CT scan confirmed the posterior dislocation. The authors discuss the features that make this case a unique case for which open reduction and fracture fixation with a pelvic reconstruction plate were chosen. Radiological follow-up confirmed recovery of the anatomy. The fracture healed and the result is a normal, functional shoulder.

  13. Anorexia Reduces GFAP+ Cell Density in the Rat Hippocampus.

    Science.gov (United States)

    Reyes-Haro, Daniel; Labrada-Moncada, Francisco Emmanuel; Varman, Durairaj Ragu; Krüger, Janina; Morales, Teresa; Miledi, Ricardo; Martínez-Torres, Ataúlfo

    2016-01-01

    Anorexia nervosa is an eating disorder observed primarily in young women. The neurobiology of the disorder is unknown but recently magnetic resonance imaging showed a volume reduction of the hippocampus in anorexic patients. Dehydration-induced anorexia (DIA) is a murine model that mimics core features of this disorder, including severe weight loss due to voluntary reduction in food intake. The energy supply to the brain is mediated by astrocytes, but whether their density is compromised by anorexia is unknown. Thus, the aim of this study was to estimate GFAP+ cell density in the main regions of the hippocampus (CA1, CA2, CA3, and dentate gyrus) in the DIA model. Our results showed that GFAP+ cell density was significantly reduced (~20%) in all regions of the hippocampus, except in CA1. Interestingly, DIA significantly reduced the GFAP+ cells/nuclei ratio in CA2 (-23%) and dentate gyrus (-48%). The reduction of GFAP+ cell density was in agreement with a lower expression of GFAP protein. Additionally, anorexia increased the expression of the intermediate filaments vimentin and nestin. Accordingly, anorexia increased the number of reactive astrocytes in CA2 and dentate gyrus more than twofold. We conclude that anorexia reduces the hippocampal GFAP+ cell density and increases vimentin and nestin expression.

  14. Sleep deprivation impairs cAMP signalling in the hippocampus.

    Science.gov (United States)

    Vecsey, Christopher G; Baillie, George S; Jaganath, Devan; Havekes, Robbert; Daniels, Andrew; Wimmer, Mathieu; Huang, Ted; Brown, Kim M; Li, Xiang-Yao; Descalzi, Giannina; Kim, Susan S; Chen, Tao; Shang, Yu-Ze; Zhuo, Min; Houslay, Miles D; Abel, Ted

    2009-10-22

    Millions of people regularly obtain insufficient sleep. Given the effect of sleep deprivation on our lives, understanding the cellular and molecular pathways affected by sleep deprivation is clearly of social and clinical importance. One of the major effects of sleep deprivation on the brain is to produce memory deficits in learning models that are dependent on the hippocampus. Here we have identified a molecular mechanism by which brief sleep deprivation alters hippocampal function. Sleep deprivation selectively impaired 3', 5'-cyclic AMP (cAMP)- and protein kinase A (PKA)-dependent forms of synaptic plasticity in the mouse hippocampus, reduced cAMP signalling, and increased activity and protein levels of phosphodiesterase 4 (PDE4), an enzyme that degrades cAMP. Treatment of mice with phosphodiesterase inhibitors rescued the sleep-deprivation-induced deficits in cAMP signalling, synaptic plasticity and hippocampus-dependent memory. These findings demonstrate that brief sleep deprivation disrupts hippocampal function by interfering with cAMP signalling through increased PDE4 activity. Thus, drugs that enhance cAMP signalling may provide a new therapeutic approach to counteract the cognitive effects of sleep deprivation.

  15. The fat-like cadherin CDH-4 acts cell-non-autonomously in anterior-posterior neuroblast migration.

    Science.gov (United States)

    Sundararajan, Lakshmi; Norris, Megan L; Schöneich, Sebastian; Ackley, Brian D; Lundquist, Erik A

    2014-08-15

    Directed migration of neurons is critical in the normal and pathological development of the brain and central nervous system. In Caenorhabditis elegans, the bilateral Q neuroblasts, QR on the right and QL on the left, migrate anteriorly and posteriorly, respectively. Initial protrusion and migration of the Q neuroblasts is autonomously controlled by the transmembrane proteins UNC-40/DCC, PTP-3/LAR, and MIG-21. As QL migrates posteriorly, it encounters and EGL-20/Wnt signal that induces MAB-5/Hox expression that drives QL descendant posterior migration. QR migrates anteriorly away from EGL-20/Wnt and does not activate MAB-5/Hox, resulting in anterior QR descendant migration. A forward genetic screen for new mutations affecting initial Q migrations identified alleles of cdh-4, which caused defects in both QL and QR directional migration similar to unc-40, ptp-3, and mig-21. Previous studies showed that in QL, PTP-3/LAR and MIG-21 act in a pathway in parallel to UNC-40/DCC to drive posterior QL migration. Here we show genetic evidence that CDH-4 acts in the PTP-3/MIG-21 pathway in parallel to UNC-40/DCC to direct posterior QL migration. In QR, the PTP-3/MIG-21 and UNC-40/DCC pathways mutually inhibit each other, allowing anterior QR migration. We report here that CDH-4 acts in both the PTP-3/MIG-21 and UNC-40/DCC pathways in mutual inhibition in QR, and that CDH-4 acts cell-non-autonomously. Interaction of CDH-4 with UNC-40/DCC in QR but not QL represents an inherent left-right asymmetry in the Q cells, the nature of which is not understood. We conclude that CDH-4 might act as a permissive signal for each Q neuroblast to respond differently to anterior-posterior guidance information based upon inherent left-right asymmetries in the Q neuroblasts. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. [Diagnostic value of MRI for posterior root tear of medial and lateral meniscus].

    Science.gov (United States)

    Qian, Yue-Nan; Liu, Fang; Dong, Yi-Long; Cai, Chun-Yuan

    2018-03-25

    To explore diagnostic value of MRI on posterior root tear of medial and lateral meniscus. From January 2012 to January 2016, clinical data of 43 patients with meniscal posterior root tear confirmed by arthroscopy were retrospective analyzed, including 25 males and 18 females, aged from 27 to 69 years old with an average age of(42.5±8.3)years old;27 cases on the right side and 16 cases on the left side. MRI examinations of 43 patients with tear of posterior meniscus root confirmed by knee arthroscopies were retrospectively reviewed. MRI images were double-blinded, independently, retrospectively scored by two imaging physicians. Sensitivity, specificity and accuracy of MRI diagnosis of lateral and medial meniscus posterior root tear were calculated, and knee ligament injury and meniscal dislocation were calculated. Forty-three of 143 patients were diagnosed with meniscus posterior root tears by arthroscopy, including 19 patients with lateral tears and 24 patients with medial tears. The sensitivity, specificity and accuracy in diagnosis of posterior medial meniscus root tears for doctor A were 91.67%, 86.6% and 83.9% respectively, and for doctor B were 87.5%, 87.4% and 87.4%, 19 patients with medial meniscal protrusion and 2 patients with anterior cruciate ligament tear. The sensitivity, specificity and accuracy in diagnosis of posterior lateral meniscus root tears for doctor A were 73.7%, 79.9% and 79% respectively, and for doctor B were 78.9%, 82.3% and 82.5%, 4 patients with lateral meniscus herniation and 16 patients with cruciate ligament tear. Kappa statistics for posterior medial meniscus root tears and posterior lateral meniscus root tears were 0.84 and 0.72. MRI could effectively demonstrate imaging features of medial and lateral meniscal root tear and its accompanying signs. It could provide the basis for preoperative diagnosis of clinicians, and be worthy to be popularized. Copyright© 2018 by the China Journal of Orthopaedics and Traumatology Press.

  17. A posterior tibial tendon skipping rope

    NARCIS (Netherlands)

    van Sterkenburg, M. N.; Haverkamp, D.; van Dijk, C. N.; Kerkhoffs, G. M. M. J.

    2010-01-01

    This report presents an athletic patient with swelling and progressive pain on the posteromedial side of his right ankle on weight bearing. MRI demonstrated tenosynovitis and suspicion of a length rupture. On posterior tibial tendoscopy, there was no rupture, but medial from the tendon a tissue cord

  18. Posterior Predictive Model Checking in Bayesian Networks

    Science.gov (United States)

    Crawford, Aaron

    2014-01-01

    This simulation study compared the utility of various discrepancy measures within a posterior predictive model checking (PPMC) framework for detecting different types of data-model misfit in multidimensional Bayesian network (BN) models. The investigated conditions were motivated by an applied research program utilizing an operational complex…

  19. Selective posterior lumbosacral rhizotomy for the management ...

    African Journals Online (AJOL)

    One hundred and sixty-eight patients had selective lumbosacral posterior rhizotomies for the treatment of cerebral palsy spasticity at Red Cross War Memorial Children's Hospital and Groote Schuur Hospital during the 10-year period 1981 - 1991. There was no mortality and insignificant early postoperative morbidity.

  20. Posterior skulderluksation--en diagnostisk udfordring

    DEFF Research Database (Denmark)

    Trollegaard, Anton Mitchell

    2009-01-01

    A case of posterior shoulder dislocation is described. The dislocation was misinterpreted twice clinically and radiographically in two different casualty departments before it was diagnosed and treated with closed reposition in a third facility. Treatment was conservative and the arm was placed...... in an abduction sling for four weeks with subsequent active physiotherapy. Udgivelsesdato: 2009-Aug...

  1. stabilisation of posterior sternoclavicular joint dislocation using

    African Journals Online (AJOL)

    A case is reported where palmaris longus tendon was used to stabilise the joint following open reduction. INTRODUCTION. Posterior Sternoclavicular joint dislocation is a relatively rare injury and is reported to have been first documented by Sir Astley Cooper in 1824 (1, 2). It is a potentially life threatening injury due to the ...

  2. Hindfoot endoscopy for posterior ankle pain

    NARCIS (Netherlands)

    van Dijk, C. Niek

    2006-01-01

    Hindfoot pain can be caused by a variety of pathologies, most of which can be diagnosed and treated with endoscopy. The main indications are posterior tibial tenosynovectomy, diagnosis of a longitudinal peroneus brevis rupture, peroneal tendon adhesiolysis, flexor hallucis longus release, os

  3. Posterior reversible encephalopathy syndrome: Some novel ...

    African Journals Online (AJOL)

    Two cases occurred following cerebral anoxia due to accidental strangulation and near-drowning, respectively. The third patient, a child known to have E-β thalassaemia, presented with transient encephalopathy following blood transfusion but involving the anterior brain rather than the posterior part classically described in ...

  4. Frozen shoulder or missed posterior dislocation?

    African Journals Online (AJOL)

    capsule and the posterior band of the inferior GH ligament. Dynamic structures are the shoulder girdle muscles and the rotator cuff. Traumatic PSD occurs when ... and subscapularis contractures, an insertion of the prosthesis is made in relatively anteverted orientation, or normal prosthetic retroversion with anterior capsular ...

  5. Extensive Supratentorial Hemorrhages Following Posterior Fossa ...

    African Journals Online (AJOL)

    Remote supratentorial hematoma soon after posterior fossa surgery for the removal of a space-occupying lesion is a rare but dramatic and dreaded complication, carrying significant morbidity and mortality. A 47-year-old woman presented with headache of 1-year duration that worsened over last 2 months, progressive ...

  6. POSTERIOR APPROACH FOR HIP ARTHROPLASTY: A SINGLE ...

    African Journals Online (AJOL)

    The most common indication was osteoarthritis. Two complications were encountered; surgical site infection and post-operative cerebrovascular accident. There were no dislocations. Conclusions: The posterior approach is a viable approach for hip arthroplasty for use in Kenya with low complication rates. INTRODUCTION.

  7. Posterior arch defects of the cervical spine

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, A.M.; Wechsler, R.J.; Landy, M.D.; Wetzner, S.M.; Goldstein, S.A.

    1982-05-01

    Spondylolysis and absence of the pedicle are congenital anomalies of the posterior cervical spine. Their roentgenographic changes may be confused with other more serious entities which may necessitate either emergent therapy or require extensive diagnostic testing and treatment. Four cases are present and the literature is reviewed. A hypothesis for the embryologic etiology of these entities is proposed.

  8. Posterior arch defects of the cervical spine

    International Nuclear Information System (INIS)

    Schwartz, A.M.; Wechsler, R.J.; Landy, M.D.; Wetzner, S.M.; Goldstein, S.A.

    1982-01-01

    Spondylolysis and absence of the pedicle are congenital anomalies of the posterior cervical spine. Their roentgenographic changes may be confused with other more serious entities which may necessitate either emergent therapy or require extensive diagnostic testing and treatment. Four cases are present and the literature is reviewed. A hypothesis for the embryologic etiology of these entities is proposed. (orig.)

  9. Restoration of the endodontically treated posterior tooth

    Directory of Open Access Journals (Sweden)

    Andrea Polesel

    2014-06-01

    Results and conclusions: Direct adhesive restorations, indirect bonded restorations and traditional full crown are three therapeutic options for the single posterior endodontically treated teeth. The amount of remaining sound tooth structure is the most significant factor influencing the therapeutic approach. The clinician's operative skill is a determining aspect for long-term success of adhesive inlays.

  10. Posterior reversibile encephalopathic syndrom: case report and review of literature

    Directory of Open Access Journals (Sweden)

    Petrović Branko B.

    2003-01-01

    Full Text Available INTRODUCTION Reversible Posterior Leukoencephalopathy Syndrome was introduced into clinical practice in 1996 in order to describe unique syndrome, clinically expressed during hypertensive and uremic encephalopathy, eclampsia and during immunosuppressive therapy [1 ]. First clinical investigations showed that leucoencephalopathy is major characteristic of the syndrome, but further investigations showed no significant destruction in white cerebral tissue [2, 3,4]. In majority of cases changes are localize in posterior irrigation area of the brain and in the most severe cases anterior region is also involved. Taking into consideration all above mentioned facts, the suggested term was Posterior Reversible Encephalopathy Syndrome (PRES for the syndrome clinically expressed by neurological manifestations derived from cortical and subcortical changes localized in posterior regions of cerebral hemispheres cerebral trunk and cerebellum [5]. CASE REPORT Patient, aged 53 years, was re-hospitalized in Cardiovascular Institute "Dedinje" two months after succesfull aorto-coronary bypass performed in June 2001 due to the chest bone infection. During the treatment of the infection (according to the antibiogram in September 2001, patient in evening hours developed headache and blurred vision. The recorded blood pressure was 210/120 mmHg so antihypertensive treatment was applied (Nifedipin and Furosemid. After this therapy there was no improvement and intensive headache with fatigue and loss of vision developed. Neurological examination revealed cortical blindness and left hemiparesis. Manitol (20%, 60 ccm every 3 hours and iv. Nytroglicerin (high blood pressure. Brain CT revealed oedema of parieto-occipital regions of both hemispheres, more emphasized on the right. (Figure 1 a, b, c. There was no sign of focal ischemia even in deeper sections (Figure 1d, e, f. Following three days enormous high blood pressure values were registered. On the fourth day the

  11. Cortical damage in the posterior visual pathway in patients with sialidosis type 1.

    Science.gov (United States)

    Lu, Chin-Song; Ng, Shu-Hang; Lai, Szu-Chia; Kao, Ling-Yuh; Liu, Laura; Lin, Wey-Yil; Wu, Yi-Ming; Chen, Yao-Liang; Wang, Jiun-Jie

    2017-02-01

    In order to identify the cortical changes in patients with Sialidosis type 1, diffusion tensor imaging and resting state fMRI were acquired from 11 patients and 11 sex/age matched normal controls after clinical evaluations. The neuroimages from each participant were normalized and parcellated according to the Automatic Anatomical Labeling. Both the mean diffusivity and the corresponding functional connectivity were calculated from each cortical region. The white matter tract integrity was examined. The difference between patients and controls was examined using Student's t-test and between patients with either homozygous or heterozygous mutations by Mann-Whitney U test, both at a threshold of 0.05. Increased mean diffusivity throughout the brain can be noticed in the patients, together with a compromised white matter tracts integrity. The most severely affected cortical regions are in the occipital lobe. Decreased functional connectivity was from the temporal and occipital lobes to the hippocampus and parahippocampus. In contrast, connectivity from thalamus was enhanced. Diffused cortical atrophy with posterior focal lesions was noticed. We concluded that MRI observed functional changes in the posterior cortical pathways in the patients with Sialidosis. The observation might be related to the cortical blindness due to an altered neural network and a compromised visual pathway in the patients.

  12. Aberrant default-mode network-hippocampus connectivity after sad memory-recall in remitted-depression.

    Science.gov (United States)

    Figueroa, Caroline A; Mocking, Roel J T; van Wingen, Guido; Martens, Suzanne; Ruhé, Henricus G; Schene, Aart H

    2017-11-01

    Rumination and cognitive reactivity (dysfunctional cognitions after sad mood-induction) remain high in remitted Major Depressive Disorder (MDD) and can contribute to new episodes. These factors have been linked to increased fMRI resting-state functional-connectivity within the Default-Mode Network (DMN). It remains unclear whether (I) increased DMN-connectivity persists during MDD-remission, and (II) whether sad mood-induction differentially affects DMN-connectivity in remitted-MDD vs controls. Moreover, DMN-connectivity studies in remitted-MDD were previously confounded by antidepressant-use. Sixty-two MDD-patients remitted from ≥2 episodes, psychotropic-medication free, and 41 controls, participated in two 5-min neutral and sad mood-inductions by autobiographical-recall and neutral/sad music, each followed by 8-min resting-state fMRI-scanning. We identified DMN-components using Independent Component Analysis and entered subject- and sessions-specific components into a repeated measures analysis of variance. Connectivity-differences were extracted and correlated with baseline cognitive reactivity and rumination as measures of vulnerability for recurrence. After sad vs neutral mood-induction, controls, but not remitted-MDD, showed an increase in connectivity between the posterior-DMN and a cluster consisting mostly of the hippocampus (P = 0.006). Less posterior-DMN-hippocampal connectivity was associated with higher cognitive reactivity (r = -0.21, P = 0.046) and rumination (r = -0.27, P = 0.017). After recalling sad autobiographical-memories, aberrant posterior-DMN-hippocampal connectivity, associated with cognitive reactivity and rumination, remains a neural vulnerability in MDD-remission. © The Author (2017). Published by Oxford University Press.

  13. The Role of Hippocampus in the Pathophysiology of Depression

    Directory of Open Access Journals (Sweden)

    Özlem Donat Eker

    2009-06-01

    Full Text Available Hippocampus, as a part of the limbic cortex, has a variety of functions ranging from mating behavior to memory besides its role in the regulation of emotions. The hippocampus has reciprocal interactions of with other brain regions which act in the pathophysiology of major depressive disorder (MDD. Moreover, since the hippocampus is a scene for the neurogenesis, which can be seen as a response to antidepressant treatment, the hippocampus became a focus of attention in neuroimaging studies of MDD. It has been shown that brain derived neurotrophic factor (BDNF, that is responsible from the neurogenesis, is associated with the response to the antidepressants and antidepressant drugs are ineffective if neurogenesis is hindered.Hippocampal atrophy is expected with the decrease of neurogenesis as a result of the lower BDNF levels with the deleterious effects of glucocorticoids in depression. Recurrent and severe depression seems to cause such a volume reduction though first episode MDD subjects do not differ from healthy individuals in respect to their hippocampal volumes (HCVs measured by magnetic resonance imaging methods. One may argue regarding these findings that the atrophy in the hippocampus may be observed in the long term and the decrease in BDNF levels may predispose the volume reduction. Although it has been postulated that smaller HCV as a result of genetic and environmental factors and prior to the illness, may cause a vulnerability to MDD, sufficient evidence has not been accumulated yet and the view that HCV loss develops as depression progresses is widely accepted. Findings that serum BDNF (sBDNF is lower in MDD patients though HCVs of patients do not differ from healthy individuals and the positive correlation of sBDNF with HCV seen only in the patient group support this view. It can be assumed that depressed patients have sensitivity for the fluctuations in BDNF levels. Follow-up studies which consider effects of hipotalamo

  14. Managing a female patient with left low back pain and sacroiliac joint pain with therapeutic exercise: a case report.

    Science.gov (United States)

    Boyle, Kyndall L

    2011-01-01

    The purpose of this case study is to describe the management of a female patient with chronic left low back pain and sacroiliac joint pain (LBP/SIJP) using unique unilateral exercises developed by the Postural Restoration Institute (PRI) to address pelvic asymmetry and left hip capsule restriction, which is consistent with a Right Handed and Left Anterior Interior Chain pattern of postural asymmetry.Client Description: The client was 65-year-old woman with a 10-month history of constant left LBP/SIJP and leg pain. The patient was seen six times to correct pelvic position/posture and left hip posterior capsule restriction via (1) muscle activation (left hamstrings, adductor magnus, and anterior gluteus medius) and (2) left hip adduction to lengthen the left posterior capsule/ischiofemoral ligament. Stabilization exercises included bilateral hamstrings, gluteus maximus, adductors, and abdominals to maintain pelvic position/posture.Measures and Outcome: Left Ober's test (initially positive) was negative at discharge. Pain as measured on the Numeric Pain Rating Scale (initially 1/10 at best and 8/10 at worst) was 0/10-0/10 at discharge. Oswestry Disability Index score (initially 20%) was 0% at discharge. The patient no longer had numbness in her left leg, and sexual intercourse had become pain free. INTERVENTIONs to restore and maintain the optimal position of pelvis and hip (femoral head in the acetabulum) may be beneficial for treating patients with chronic LBP/SIJP. The patient's pain was eliminated 13 days after she first performed three exercises to reposition the pelvis and restore left posterior hip capsule extensibility and internal rotation.

  15. Left main percutaneous coronary intervention.

    Science.gov (United States)

    Teirstein, Paul S; Price, Matthew J

    2012-10-23

    The introduction of drug-eluting stents and advances in catheter techniques have led to increasing acceptance of percutaneous coronary intervention (PCI) as a viable alternative to coronary artery bypass graft (CABG) for unprotected left main disease. Current guidelines state that it is reasonable to consider unprotected left main PCI in patients with low to intermediate anatomic complexity who are at increased surgical risk. Data from randomized trials involving patients who are candidates for either treatment strategy provide novel insight into the relative safety and efficacy of PCI for this lesion subset. Herein, we review the current data comparing PCI with CABG for left main disease, summarize recent guideline recommendations, and provide an update on technical considerations that may optimize clinical outcomes in left main PCI. Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  16. Left bundle-branch block

    DEFF Research Database (Denmark)

    Risum, Niels; Strauss, David; Sogaard, Peter

    2013-01-01

    The relationship between myocardial electrical activation by electrocardiogram (ECG) and mechanical contraction by echocardiography in left bundle-branch block (LBBB) has never been clearly demonstrated. New strict criteria for LBBB based on a fundamental understanding of physiology have recently...

  17. Dabigatran for left ventricular thrombus

    Directory of Open Access Journals (Sweden)

    Satishkumar Kolekar

    2015-09-01

    Dabigatran is a reversible direct thrombin inhibitor and currently approved for the prevention of thromboembolic episodes in non-valvar atrial fibrillation. This case demonstrates possible thrombolytic properties of dabigatran in resolution of left ventricular thrombus.

  18. Measuring the volume of the hippocampus in healthy Chinese adults of the Han nationality on the high-resolution MRI

    International Nuclear Information System (INIS)

    Zhang Yong; Chen Nan; Wang Xing; Li Kuncheng; Zhuo Yan; Chen Lin

    2010-01-01

    Objective: To measure the volume of hippocampal formation (HPF) in healthy Chinese Han adults and provide database for researching on a variety of diseases associated with alteration of hippocampal structure. Methods: This is a clinical multi-center study. One thousand Chinese healthy volunteers (age range=18 to 70) recruited from 15 hospitals were divided into 5 groups, i. e., Group A (age range=18 to 30), B (age range=31 to 40), C (age range =41 to 50), D (age range =51 to 60), and E (age range = 61 to 70). Each group contained 100 males and 100 females. All of the volunteers were scanned by MR using T 1 weighted three-dimensional magnetization prepared rapid acquisition gradient echo sequence. The margin of HPF were outlined manually for each side. Using multiple linear regression, relationships between hippocampal volume and sex, age, weight and height were analyzed respectively. Independent two sample t test was used to study the differences between male and female and between left and right. The differences of hippocampal volume among age groups were analyzed by ANOVA. Results: Hippocampal volume for left and right side were (4752±659) and (5032±660) mm 3 respectively. The volume of HPF is significant correlated with gender and age, but without relevance to height and weight (left and right r=0.283,0.311, F=30.127,37.050,P 3 respectively for men, and (4647±624) and (4904±630) mm 3 for women. The right hippocampal volume was larger than the left (t=7.030,6.696, P 3 respectively, while the volumes of the fight hippocampus were (5340± 647), (5276±582), (5264±620), (5133±661), (4894±699) mm 3 respectively. Among age groups, the differences were statistically significant (left and right F=5.737,7.607, P 0.05). There was no significant difference of hippocampal among different groups in women (P>0.05). Conclusions: With high-resolution MRI, the volume of the HPF was accurately measured, so as to provide the basic data for research of the hippocampus

  19. Topographic anatomical study of the sciatic nerve relationship to the posterior portal in hip arthroscopy

    Directory of Open Access Journals (Sweden)

    Berliet Assad Gomes

    Full Text Available Objective: To evaluate the anatomic topographic relation between the sciatic nerve in relation to the piriform muscle and the posterior portal for the establishment of hip arthroscopy.Methods: We dissected 40 hips of 20 corpses of adult Brazilians, 17 male and three female, six black, six brown and eight white. We studied the anatomical relationship between the sciatic nerve and the piriform muscle with their variations and the distance between the lateral edge of the sciatic nerve and the posterior portal used in hip arthroscopy. We then classified the anatomical alterations found in the path of the sciatic nerve on the piriform muscle.Results: Seventeen corpses had bilateral relationship between the sciatic nerve and the piriform muscle, i.e., type A. We found the following anatomical variations: 12.5% of variant type B; and an average distance between the sciatic nerve and the portal for arthroscopy of 2.98cm. One body had type B anatomical variation on the left hip and type A on the right.Conclusion: the making of the posterior arthroscopic portal to the hip joint must be done with careful marking of the trochanter massive; should there be difficult to find it, a small surgical access is recommended. The access point to the portal should not exceed two centimeters towards the posterior superior aspect of the greater trochanter, and must be made with the limb in internal rotation of 15 degrees.

  20. High interocular corneal symmetry in average simulated keratometry, central corneal thickness, and posterior elevation.

    Science.gov (United States)

    Myrowitz, Elliott H; Kouzis, Anthony C; O'Brien, Terrence P

    2005-05-01

    The purpose of this study was to assess interocular corneal symmetry in average simulated keratometry, corneal thickness, and posterior corneal elevation. This retrospective analysis included data from scanning slit topography (Orbscan II; Bausch and Lomb, Rochester, NY) on 242 eyes from 121 consecutive patients undergoing standard evaluation for consideration of elective laser vision correction. The symmetry between the right and left eye in average simulated keratometry, minimum central corneal thickness, and posterior corneal elevation was assessed by comparative data analysis. Simulated keratometry ranged from 39.9 to 48.6 D. The interocular difference in average simulated keratometry was 0.47 D (standard deviation [SD] 0.43). The interocular Pearson correlation coefficient for average simulated keratometry was 0.90 (p central corneal thickness was 0.95 (p symmetry in all these parameters was very high in this group of consecutive patients. Asymmetry of these interocular parameters may warrant repeat clinical testing for accuracy and may predict corneal abnormalities. Normative data on posterior cornea elevation is presented. This study points out potentially clinically important high interocular corneal symmetry data in simulated keratometry, corneal thickness, and posterior corneal elevation.

  1. Apraxia in left-handers.

    Science.gov (United States)

    Goldenberg, Georg

    2013-08-01

    In typical right-handed patients both apraxia and aphasia are caused by damage to the left hemisphere, which also controls the dominant right hand. In left-handed subjects the lateralities of language and of control of the dominant hand can dissociate. This permits disentangling the association of apraxia with aphasia from that with handedness. Pantomime of tool use, actual tool use and imitation of meaningless hand and finger postures were examined in 50 consecutive left-handed subjects with unilateral hemisphere lesions. There were three aphasic patients with pervasive apraxia caused by left-sided lesions. As the dominant hand is controlled by the right hemisphere, they constitute dissociations of apraxia from handedness. Conversely there were also three patients with pervasive apraxia caused by right brain lesions without aphasia. They constitute dissociations of apraxia from aphasia. Across the whole group of patients dissociations from handedness and from aphasia were observed for all manifestations of apraxia, but their frequency depended on the type of apraxia. Defective pantomime and defective tool use occurred rarely without aphasia, whereas defective imitation of hand, but not finger, postures was more frequent after right than left brain damage. The higher incidence of defective imitation of hand postures in right brain damage was mainly due to patients who had also hemi-neglect. This interaction alerts to the possibility that the association of right hemisphere damage with apraxia has to do with spatial aptitudes of the right hemisphere rather than with its control of the dominant left hand. Comparison with data from right-handed patients showed no differences between the severity of apraxia for imitation of hand or finger postures, but impairment on pantomime of tool use was milder in apraxic left-handers than in apraxic right-handers. This alleviation of the severity of apraxia corresponded with a similar alleviation of the severity of aphasia as

  2. Left ventricular apical ballooning syndrome

    International Nuclear Information System (INIS)

    Rahman, N.; Tai, J.; Soofi, A.

    2007-01-01

    The transient left ventricular apical ballooning syndrome, also known as Takotsubo cardiomyopathy, is characterized by transient left ventricular dysfunction in the absence of obstructive epicardial coronary disease. Although the syndrome has been reported in Japan since 1990, it is rare in other regions. Rapid recognition of the syndrome can modify the diagnostic and therapeutic attitude i.e. avoiding thrombolysis and performing catheterization in the acute phase. (author)

  3. Lumbar sagittal contour after posterior interbody fusion: threaded devices alone versus vertical cages plus posterior instrumentation.

    Science.gov (United States)

    Klemme, W R; Owens, B D; Dhawan, A; Zeidman, S; Polly, D W

    2001-03-01

    An observational radiographic study examining lumbar sagittal contour of patients undergoing posterior interbody arthrodesis. To compare operative alterations of lumbar sagittal contour after posterior interbody fusion using threaded interbody devices alone versus vertical cages combined with posterior compression instrumentation. Technique-related alterations of lumbar sagittal contour during interbody arthrodesis have received little attention in the spinal literature. Standing lumbar radiographs were measured for preoperative and postoperative segmental lordosis at levels undergoing posterior interbody arthrodesis using either stand-alone side-by-side threaded devices or vertical cages combined with posterior transpedicular compression instrumentation. Sagittal plane segmental correction (or loss of correction) was calculated and statistically compared. The radiographs of 30 patients (34 spinal segments) undergoing lumbar or lumbosacral arthrodesis were compared. Seventeen patients (18 segments) had undergone interbody fusion using threaded cages,whereas 13 patients (16 segments) underwent fusion using vertically oriented mesh cages combined with posterior compression instrumentation. Preoperative segmental lordosis averaged 8 degrees for both groups. For patients undergoing fusion with threaded cages, there was a mean lordotic loss of 3 degrees/segment. For patients undergoing fusion with vertically oriented mesh cages combined with posterior compression instrumentation,there was a mean lordotic gain of 5 degrees/segment. This difference in segmental sagittal plane contour was highly significant (P = 0.00). Threaded fusion devices placed under interbody distraction with the endplates parallel fail to preserve or reestablish segmental lordosis. Vertical cages, however, when combined with posterior compression instrumentation, not only maintain segmental lordosis, but also can correct sagittal plane deformity.

  4. Associations of olfactory bulb and depth of olfactory sulcus with basal ganglia and hippocampus in patients with Parkinson's disease.

    Science.gov (United States)

    Tanik, Nermin; Serin, Halil Ibrahim; Celikbilek, Asuman; Inan, Levent Ertugrul; Gundogdu, Fatma

    2016-05-04

    Parkinson's disease (PD) is a neurodegenerative disorder characterized by hyposmia in the preclinical stages. We investigated the relationships of olfactory bulb (OB) volume and olfactory sulcus (OS) depth with basal ganglia and hippocampal volumes. The study included 25 patients with PD and 40 age- and sex-matched control subjects. Idiopathic PD was diagnosed according to published diagnostic criteria. The Hoehn and Yahr (HY) scale, the motor subscale of the Unified Parkinson's Disease Rating Scale (UPDRS III), and the Mini-Mental State Examination (MMSE) were administered to participants. Volumetric measurements of olfactory structures, the basal ganglia, and hippocampus were performed using magnetic resonance imaging (MRI). OB volume and OS depth were significantly reduced in PD patients compared to healthy control subjects (p<0.001 and p<0.001, respectively). The OB and left putamen volumes were significantly correlated (p=0.048), and the depth of the right OS was significantly correlated with right hippocampal volume (p=0.018). We found significant correlations between OB and putamen volumes and OS depth and hippocampal volume. Our study is the first to demonstrate associations of olfactory structures with the putamen and hippocampus using MRI volumetric measurements. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. Electroacupuncture Improved the Function of Myocardial Ischemia Involved in the Hippocampus-Paraventricular Nucleus-Sympathetic Nerve Pathway

    Directory of Open Access Journals (Sweden)

    Shuai Cui

    2018-01-01

    Full Text Available We investigated the hippocampus-paraventricular nucleus- (PVN- sympathetic nerve pathway in electroacupuncture (EA at the heart meridian for the treatment of myocardial ischemia by observing PVN neuronal discharge, sympathetic nerve discharge, and hemodynamics parameters. Sprague Dawley (SD rats were equally divided into four groups: Sham, Model, Model + EA, and Model + EA + Lesion. The model rat was established by ligating the left anterior descending branch of the coronary artery. Changes in the sympathetic nerve discharge and hemodynamic parameters were observed. The Model + EA exhibited a significantly lower discharge frequency of PVN neurons compared with the Model. The Model + EA + Lesion had a significantly higher discharge frequency compared with the Model + EA. The total discharge frequency of PVN neurons and interneurons were positively correlated with the sympathetic nerve discharge. The total discharge frequency of PVN neurons was positively correlated with heart rate (HR and negatively correlated with mean arterial pressure (MAP and rate pressure product (RPP. The discharge frequency of interneurons was positively correlated with HR and negatively correlated with MAP and RPP. The hippocampus-PVN-sympathetic nerve pathway is involved in electroacupuncture at the heart meridian and interneurons are the key neurons in PVNs.

  6. Left Main Coronary Artery Aneurysm

    Directory of Open Access Journals (Sweden)

    Hossein Doustkami

    2016-07-01

    Full Text Available Aneurysms of the left main coronary artery are exceedingly rare clinical entities, encountered incidentally in approximately 0.1% of patients who undergo routine angiography. The most common cause of coronary artery aneurysms is atherosclerosis. Angiography is the gold standard for diagnosis and treatment. Depending on the severity of the coexisting coronary stenosis, patients with left main coronary artery aneurysms can be effectively managed either surgically or pharmacologically. We herein report a case of left main coronary artery aneurysm in a 72-year-old man with a prior history of hypertension presenting to our hospital because of unstable angina. The electrocardiogram showed ST-segment depression and T-wave inversion in the precordial leads. All the data of blood chemistry were normal. Echocardiography showed akinetic anterior wall, septum, and apex, mild mitral regurgitation and ejection fraction of 45%. Coronary angiography revealed a saccular aneurysm of the left main coronary artery with significant stenosis in the left anterior descending, left circumflex, and right coronary artery. The patient immediately underwent coronary artery bypass grafting and ligation of the aneurysm. At six months’ follow-up, he remained asymptomatic.

  7. Right colon cancer: Left behind.

    Science.gov (United States)

    Gervaz, P; Usel, M; Rapiti, E; Chappuis, P; Neyroud-Kaspar, I; Bouchardy, C

    2016-09-01

    Prognosis of colon cancer (CC) has steadily improved during the past three decades. This trend, however, may vary according to proximal (right) or distal (left) tumor location. We studied if improvement in survival was greater for left than for right CC. We included all CC recorded at the Geneva population-based registry between 1980 and 2006. We compared patients, tumor and treatment characteristics between left and right CC by logistic regression and compared CC specific survival by Cox models taking into account putative confounders. We also compared changes in survival between CC location in early and late years of observation. Among the 3396 CC patients, 1334 (39%) had right-sided and 2062 (61%) left-sided tumors. In the early 1980s, 5-year specific survival was identical for right and left CCs (49% vs. 48%). During the study period, a dramatic improvement in survival was observed for patients with left-sided cancers (Hazard ratio [HR]: 0.42, 95% confidence interval [CI]: 0.29-0.62, p colon cancer patients, those with right-sided lesions have by far the worse prognosis. Change of strategic management in this subgroup is warranted. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Posterior Wnts Have Distinct Roles in Specification and Patterning of the Planarian Posterior Region

    Directory of Open Access Journals (Sweden)

    Miquel Sureda-Gómez

    2015-11-01

    Full Text Available The wnt signaling pathway is an intercellular communication mechanism essential in cell-fate specification, tissue patterning and regional-identity specification. A βcatenin-dependent signal specifies the AP (Anteroposterior axis of planarians, both during regeneration of new tissues and during normal homeostasis. Accordingly, four wnts (posterior wnts are expressed in a nested manner in central and posterior regions of planarians. We have analyzed the specific role of each posterior wnt and the possible cooperation between them in specifying and patterning planarian central and posterior regions. We show that each posterior wnt exerts a distinct role during re-specification and maintenance of the central and posterior planarian regions, and that the integration of the different wnt signals (βcatenin dependent and independent underlies the patterning of the AP axis from the central region to the tip of the tail. Based on these findings and data from the literature, we propose a model for patterning the planarian AP axis.

  9. Posterior Wnts Have Distinct Roles in Specification and Patterning of the Planarian Posterior Region

    Science.gov (United States)

    Sureda-Gómez, Miquel; Pascual-Carreras, Eudald; Adell, Teresa

    2015-01-01

    The wnt signaling pathway is an intercellular communication mechanism essential in cell-fate specification, tissue patterning and regional-identity specification. A βcatenin-dependent signal specifies the AP (Anteroposterior) axis of planarians, both during regeneration of new tissues and during normal homeostasis. Accordingly, four wnts (posterior wnts) are expressed in a nested manner in central and posterior regions of planarians. We have analyzed the specific role of each posterior wnt and the possible cooperation between them in specifying and patterning planarian central and posterior regions. We show that each posterior wnt exerts a distinct role during re-specification and maintenance of the central and posterior planarian regions, and that the integration of the different wnt signals (βcatenin dependent and independent) underlies the patterning of the AP axis from the central region to the tip of the tail. Based on these findings and data from the literature, we propose a model for patterning the planarian AP axis. PMID:26556349

  10. Posterior Pole Sparing Laser Photocoagulation Combined with Intravitreal Bevacizumab Injection in Posterior Retinopathy of Prematurity

    Directory of Open Access Journals (Sweden)

    Rebecca Kim

    2014-01-01

    Full Text Available Purpose. To report the results of the posterior pole sparing laser photocoagulation combined with intravitreal bevacizumab injection (IVB in retinopathy of prematurity (ROP. Methods. A retrospective chart review of premature babies with ROP, all of whom received laser photocoagulation with IVB. Eleven eyes of 6 infants with advanced zone I ROP underwent laser ablation sparing posterior pole with concurrent IVB. The results were compared with those of full-laser treatment combined with IVB to 8 eyes of 5 infants with advanced ROP without involvement of the posterior pole. Results. The posterior pole sparing laser with IVB was performed with zone I, stage 3+ ROP at the mean postmenstrual age of 36 weeks and 5 days. The plus sign decreased significantly at postoperative day 1, the neovascular proliferation regressed by postoperative week 1, and the normal vascularization started at postoperative day 32 on the average. Two months after treatment, vascularization of the spared avascular area was completed. There was no macular dragging, tractional retinal detachment, foveal destruction by laser scars, or any other adverse event. No significant anatomical differences were identified from those of full-laser ablation combined with IVB. Conclusions. Posterior pole sparing laser with IVB can give favorable results without destruction of posterior pole retina.

  11. The eye in the neck: removal of a sewing needle from the posterior pharyngeal wall.

    Science.gov (United States)

    Unadkat, Samit N; Talwar, Rishi; Tolley, Neil

    2010-01-01

    Foreign body ingestion is a frequent presenting complaint to most emergency departments but the finding of a sewing needle in the posterior pharynx particularly is a rare finding. We report a case of a male patient with a sewing needle lodged in the posterior pharynx despite a history suggestive of chicken bone ingestion, absent clinical features, and negative flexible endoscopic examination. The needle was only identified through cervical spine radiographs. Even subsequent pharyngoscopy, laryngoscopy, and upper oesophagoscopy all proved to be unremarkable with the patient eventually requiring a left neck exploration to remove the needle. The case outlines the importance of simple radiography in suspected foreign body ingestion, even though clinical and endoscopic findings may be unremarkable.

  12. The Eye in the Neck: Removal of a Sewing Needle from the Posterior Pharyngeal Wall

    Directory of Open Access Journals (Sweden)

    Samit N. Unadkat

    2010-01-01

    Full Text Available Foreign body ingestion is a frequent presenting complaint to most emergency departments but the finding of a sewing needle in the posterior pharynx particularly is a rare finding. We report a case of a male patient with a sewing needle lodged in the posterior pharynx despite a history suggestive of chicken bone ingestion, absent clinical features, and negative flexible endoscopic examination. The needle was only identified through cervical spine radiographs. Even subsequent pharyngoscopy, laryngoscopy, and upper oesophagoscopy all proved to be unremarkable with the patient eventually requiring a left neck exploration to remove the needle. The case outlines the importance of simple radiography in suspected foreign body ingestion, even though clinical and endoscopic findings may be unremarkable.

  13. Altered anterior-posterior connectivity through the arcuate fasciculus in temporal lobe epilepsy.

    Science.gov (United States)

    Takaya, Shigetoshi; Liu, Hesheng; Greve, Douglas N; Tanaka, Naoaki; Leveroni, Catherine; Cole, Andrew J; Stufflebeam, Steven M

    2016-12-01

    How the interactions between cortices through a specific white matter pathway change during cognitive processing in patients with epilepsy remains unclear. Here, we used surface-based structural connectivity analysis to examine the change in structural connectivity with Broca's area/the right Broca's homologue in the lateral temporal and inferior parietal cortices through the arcuate fasciculus (AF) in 17 patients with left temporal lobe epilepsy (TLE) compared with 17 healthy controls. Then, we investigated its functional relevance to the changes in task-related responses and task-modulated functional connectivity with Broca's area/the right Broca's homologue during a semantic classification task of a single word. The structural connectivity through the AF pathway and task-modulated functional connectivity with Broca's area decreased in the left midtemporal cortex. Furthermore, task-related response decreased in the left mid temporal cortex that overlapped with the region showing a decrease in the structural connectivity. In contrast, the region showing an increase in the structural connectivity through the AF overlapped with the regions showing an increase in task-modulated functional connectivity in the left inferior parietal cortex. These structural and functional changes in the overlapping regions were correlated. The results suggest that the change in the structural connectivity through the left frontal-temporal AF pathway underlies the altered functional networks between the frontal and temporal cortices during the language-related processing in patients with left TLE. The left frontal-parietal AF pathway might be employed to connect anterior and posterior brain regions during language processing and compensate for the compromised left frontal-temporal AF pathway. Hum Brain Mapp 37:4425-4438, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  14. Giant nodular posterior scleritis simulating choroidal melanoma

    Directory of Open Access Journals (Sweden)

    Shukla Dhananjay

    2006-01-01

    Full Text Available A 45-year-old woman, complaining of sudden visual loss in the right eye (best-corrected visual acuity: 17/200, was suspected of having a malignant melanoma of the choroid. Fundus examination revealed a massive pale-colored subretinal mass temporal to the fovea, with adjoining choroidal folds and exudative retinal detachment. Ultrasonography was suggestive of posterior scleritis. Systemic evaluation was unremarkable. The patient was treated with high-dose systemic corticosteroids. The mass lesion resolved completely, with visual recovery to 20/20. Posterior scleritis should be suspected when evaluating subretinal mass-lesions, even when large and without overt inflammation. Early treatment may improve the visual prognosis and avoid misdirected management, including enucleation.

  15. Posterior reversible encephalopathy syndrome: A case report

    Directory of Open Access Journals (Sweden)

    Kostić Dejan

    2015-01-01

    Full Text Available Posterior reversible encephalopathy syndrome (PRES is characterized by the following symptoms: seizures, impaired consciousness and/or vision, vomiting, nausea, and focal neurological signs. Diagnostic imaging includes examination by magnetic resonance (MR and computed tomography (CT, where brain edema is visualized bi-laterally and symmetrically, predominantly posteriorly, parietally, and occipitally. Case report. We presented a 73-year-old patient with the years-long medical history of hipertension and renal insufficiency, who developed PRES with the symptomatology of the rear cranium. CT and MR verified changes in the white matter involving all lobes on both sides of the brain. After a two-week treatment (antihypertensive, hypolipemic and rehydration therapy clinical improvement with no complications occurred, with complete resolution of changes in the white matter observed on CT and MR. Conclusion. PRES is a reversible syndrome in which the symptoms withdraw after several days to several weeks if early diagnosis is made and appropriate treatment started without delay.

  16. Central Retinal and Posterior Ciliary Artery Occlusion After Intralesional Injection of Sclerosant to Glabellar Subcutaneous Hemangioma

    International Nuclear Information System (INIS)

    Matsuo, Toshihiko; Fujiwara, Hiroyasu; Gobara, Hideo; Mimura, Hidefumi; Kanazawa, Susumu

    2009-01-01

    The aim of this study is to describe vision loss caused by central retinal artery and posterior ciliary artery occlusion as a consequence of sclerotherapy with a polidocanol injection to a glabellar hemangioma. An 18-year-old man underwent direct injection with a 23-gauge needle of 1 mL of a polidocanol-carbon dioxide emulsion into the glabellar subcutaneous hemangioma under ultrasound visualization of the needle tip by radiologists. He developed lid swelling the next day, and 3 days later at referral, the visual acuity in the left eye was no light perception. Funduscopy revealed central retinal artery occlusion and fluorescein angiography disclosed no perfusion at all in the left fundus, indicating concurrent posterior ciliary artery occlusion. The patient also showed mydriasis, blepharoptosis, and total external ophthalmoplegia on the left side. Magnetic resonance imaging demonstrated the swollen medial rectus muscle. In a month, blepharoptosis and ophthalmoplegia resolved but the visual acuity remained no light perception. Sclerosing therapy for facial hemangioma may develop a severe complication such as permanent visual loss.

  17. Sound sensitivity of neurons in rat hippocampus during performance of a sound-guided task

    Science.gov (United States)

    Vinnik, Ekaterina; Honey, Christian; Schnupp, Jan; Diamond, Mathew E.

    2012-01-01

    To investigate how hippocampal neurons encode sound stimuli, and the conjunction of sound stimuli with the animal's position in space, we recorded from neurons in the CA1 region of hippocampus in rats while they performed a sound discrimination task. Four different sounds were used, two associated with water reward on the right side of the animal and the other two with water reward on the left side. This allowed us to separate neuronal activity related to sound identity from activity related to response direction. To test the effect of spatial context on sound coding, we trained rats to carry out the task on two identical testing platforms at different locations in the same room. Twenty-one percent of the recorded neurons exhibited sensitivity to sound identity, as quantified by the difference in firing rate for the two sounds associated with the same response direction. Sensitivity to sound identity was often observed on only one of the two testing platforms, indicating an effect of spatial context on sensory responses. Forty-three percent of the neurons were sensitive to response direction, and the probability that any one neuron was sensitive to response direction was statistically independent from its sensitivity to sound identity. There was no significant coding for sound identity when the rats heard the same sounds outside the behavioral task. These results suggest that CA1 neurons encode sound stimuli, but only when those sounds are associated with actions. PMID:22219030

  18. Hippocampus volume and subjective sleepiness in older people with sleep-disordered breathing: a preliminary report.

    Science.gov (United States)

    Sforza, Emilia; Celle, Sébastien; Saint-Martin, Magali; Barthélémy, Jean C; Roche, Frédéric

    2016-04-01

    Sleep-disordered breathing (SDB) is associated with excessive daytime sleepiness (EDS) and explained by sleep fragmentation and hypoxaemia, both contributing to brain morphology abnormalities. Recent data on middle-aged SDB patients suggest a link between hippocampus volume (HV) and EDS. We tested this hypothesis in a group of SDB older subjects. A total of 232 healthy participants aged 75 ± 0.9 years were examined. Subjective EDS was assessed by the Epworth Sleep Questionnaire (ESS), with a mean score of 5.6 ± 3.5. Volumetric segmentation of the right (RHV) and left HV (LHV) were measured using FreeSurfer software. All subjects underwent extensive cognitive testing to exclude neurological disease, as well as ambulatory polygraphy to assess SDB status. Sleepy subjects showed a lower HV. In a correlation analysis, RHV (r = -0.162, P = 0.01) and LHV (r = -170, P = 0.05) were correlated negatively with ESS and not associated with respiratory data. Multiple regression analysis did not reveal any effect of age, gender, SDB severity and hypoxia. ESS was the only factor possibly explaining the lower RHV (P = -0.03) and LHV (P = -0.04). In older people with SDB, the subjective EDS was associated with lower HV. This morphological finding should be considered on the pathogenesis of sleepiness in SDB patients. NCT 00759304 and NCT 00766584. © 2015 European Sleep Research Society.

  19. Primary posterior perineal herniation of urinary bladder

    Directory of Open Access Journals (Sweden)

    Kurumboor Prakash

    2013-01-01

    Full Text Available Primary perineal hernia is a rare clinical condition wherein herniation of viscera occurs through pelvic diaphragm. They are usually mistaken for sciatic hernia, rectal prolapse or other diseases in the perineum. Correct identification of the type of hernia by imaging is crucial for planning treatment. We present a case of primary posterior herniation of urinary bladder and rectal wall through levator ani repaired laparoscopically using a mesh repair.

  20. Reversible Posterior Leukoencephalopathy Syndrome Induced by Pazopanib

    International Nuclear Information System (INIS)

    Chelis, Leonidas; Kakolyris, Stylianos; Souftas, Vasilios; Amarantidis, Kiriakos; Xenidis, Nikolaos; Chamalidou, Eleni; Dimopoulos, Prokopios; Michailidis, Prodromos; Christakidis, Evagelos; Prassopoulos, Panagiotis

    2012-01-01

    The reversible posterior leukoencephalopathy syndrome is a clinical/radiological syndrome characterized by headache, seizures, impaired vision, acute hypertension, and typical magnetic resonance imaging findings. There are several reports in the literature that depict its occurrence in cancer patients. The list of common anticancer and supportive care drugs that predispose to reversible posterior leukoencephalopathy syndrome is expanding and includes not only a large number of chemotherapeutic agents but also an increased number of new targeted drugs, particularly angiogenesis inhibitors such as bevacizumab,sorefenib and sunitinib. Pazopanib is an oral tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit which after a positive phase III randomized clinical trial in patients with advanced renal cell cancer received FDA approval for the treatment of advanced renal cell carcinoma. Until now no cases of reversible posterior leukoencephalopathy syndrome induced by pazopanib have been reported. We present the case of a 40 years old female patient with heavily pre-treated metastatic renal cell carcinoma who received pazopanib as salvage treatment. After 21 days of pazopanib therapy the patient referred to the emergency department with epileptic seizure, impaired vision at both eyes and headache. MRI of the brain revealed subcortical oedema at the occipital and parietal lobes bilaterally. She was treated with anticonvulsants, i.v. administration of mannitol and antihypertensives and she recovered completely from her symptoms and was discharged on the tenth hospital day. A brain MRI performed 3 weeks after showed that the subcortical oedema had been subsided. In conclusion this is the first case of pazopanib induced reversible posterior leukoencephalopathy syndrome. Although usually reversible, this syndrome is a serious and potentially life threatening adverse effect, if untreated, that should

  1. Reversible posterior leukoencephalopathy after combination chemotherapy

    International Nuclear Information System (INIS)

    Honkaniemi, J.; Latvala, M.; Hietaharju, A.; Ollikainen, J.; Vaehaemaeki, L.; Frey, H.; Kaehaerae, V.; Dastidar, P.; Salonen, T.; Keskinen, L.; Kellokumpu-Lehtinen, P.

    2000-01-01

    We describe a young woman with Burkitt's lymphoma, treated with intravenous adriamycine and cyclophosphamide and intrathecal cytarabine. She developed a reversible posterior leukoencephalopathy syndrome (RPLS) with typical MRI findings. Diffusion-weighted images during the first days after the onset of symptoms predicted a small irreversible lesion in the frontal lobe, verified on T2-weighted images 1 month later. The patient showed full recovery after high-dose steroid treatment. (orig.)

  2. Indirect posterior composite inlays and onlays.

    Science.gov (United States)

    Landman, P

    1994-01-01

    Indirect posterior composite inlays and onlays are a valuable part of the cosmetic dentist's repertoire of services. They fulfill most of the requirements for an esthetic alternative to the previously considered amalgam, gold, porcelain, and directly placed composite restorations. As in all other cosmetic dental procedures, attention to detail is essential for success. Improving technology will continue to have an impact on the place these restorations occupy in future cosmetic practice.

  3. CT in thrombosed dilated posterior epidural vein

    Energy Technology Data Exchange (ETDEWEB)

    Bammatter, S.; Schnyder, P.; Preux, J. de

    1987-05-01

    The authors report a case of thrombosis of the distal end of an enlarged right posterior epidural vein. The patient had a markedly narrow lumbar canal due to L5 spondylolisthesis. The dilated vein and the thrombosis were displayed by computed tomography but remained unrecognized until surgery. Pathogenesis of this condition is discussed. A review of the English, French and German literature revealed no prior radiological reports of a similar condition.

  4. Cyclosporine-related reversible posterior leukoencephalopathy: MRI

    International Nuclear Information System (INIS)

    Jarosz, J.M.; Howlett, D.C.; Cox, T.C.S.; Bingham, J.B.

    1997-01-01

    Three patients aged 48, 11 and 40 years, two of whom were recent recipients of renal transplants and one of a bone marrow transplant, developed seizures, with cortical blindness in two cases. All were immunosuppressed with cyclosporine and were hypertensive at the onset of symptoms. MRI showed predominantly posterior signal changes in all three cases. The abnormalities were more conspicuous on fast FLAIR images than on conventional T2-weighted spin-echo images. (orig.). With 4 figs

  5. Bayesian Posterior Distributions Without Markov Chains

    OpenAIRE

    Cole, Stephen R.; Chu, Haitao; Greenland, Sander; Hamra, Ghassan; Richardson, David B.

    2012-01-01

    Bayesian posterior parameter distributions are often simulated using Markov chain Monte Carlo (MCMC) methods. However, MCMC methods are not always necessary and do not help the uninitiated understand Bayesian inference. As a bridge to understanding Bayesian inference, the authors illustrate a transparent rejection sampling method. In example 1, they illustrate rejection sampling using 36 cases and 198 controls from a case-control study (1976–1983) assessing the relation between residential ex...

  6. Posterior midline cervical fetal cystic hygroma.

    Directory of Open Access Journals (Sweden)

    Oak S

    1992-04-01

    Full Text Available Posterior midline cervical cystic hygromas (PMC are frequently found associated with chromosomal aberrations and usually do not survive. The present report illustrates diagnosis of this condition by sonography in an 18 weeks old fetus and an amniocentesis revealed 45 x0 karyotype and increased concentration of alpha-fetoproteins. Pregnancy was terminated in view of Turner′s syndrome. The etiology and natural history of the condition is reviewed.

  7. Posterior sternoclavicular dislocation: an American football injury

    DEFF Research Database (Denmark)

    Marker, L B; Klareskov, B

    1996-01-01

    Posterior dislocation of the sternoclavicular joint is uncommon, accounting for less than 0.1% of all dislocations. Since 1824 a little more than 100 cases have been reported, and the majority in the past 20 years. A review of published reports suggests that this injury is seen particularly in co...... in connection with American football. A typical case is described. The importance of this injury is that there is often a delay in diagnosis with potentially serious complications....

  8. Morphology of dentate granule cells in the human epileptogenic hippocampus.

    Science.gov (United States)

    von Campe, G; Spencer, D D; de Lanerolle, N C

    1997-01-01

    Hippocampal dentate granule cells in temporal lobe epilepsy (TLE) patients with mesial sclerosis (MTLE) are reported to be hyperexcitable compared to those in patients with a mass lesion outside the hippocampus (MaTLE) (Williamson, Clin Neurosci 1994;2: 47-52). To determine if such hyperexcitability is associated with an altered morphology of these neurons, Lucifer Yellow-filled granule cells from MTLE patients were compared with those from MaTLE. The morphology of granule cells in both subject groups resembles closely that of human granule cells described previously by Golgi studies. About 40% of human granule cells have basal dendrites. Additionally their apical dendrites are much more limited in their spread in the longitudinal axis of the hippocampus contributing perhaps to a much more narrow lamellar organization than in rats. Analysis of variance computed on 21 morphometric parameters reveals a significant increase in the length of the portion of the dendrite in the inner molecular layer (IML), and a decrease in length in the outer third of the molecular layer in MTLE, compared to MaTLE. Factor analysis performed on the morphometric features of each group of neurons reveals that in the MaTLE neurons the most distinctive feature is the total dendritic length and the overall distribution of spines on them, whereas in MTLE a lengthening and elaboration of the dendrites in the IML is most distinctive. Previous observations of increased synaptic terminals containing neuropeptides, and neurotransmitter receptors in the IML taken in conjunction with an elaboration of granule cell dendrites in this region, suggest considerable synaptic reorganization within the IML of the MTLE hippocampus which may contribute to its epileptogenicity.

  9. Leptin potentiates GABAergic synaptic transmission in the developing rodent hippocampus.

    Directory of Open Access Journals (Sweden)

    Damien eGuimond

    2014-08-01

    Full Text Available It is becoming increasingly clear that leptin is not only a hormone regulating energy homeostasis but also a neurotrophic factor impacting a number of brain regions, including the hippocampus. Although leptin promotes the development of GABAergic transmission in the hypothalamus, little is known about its action on the GABAergic system in the hippocampus. Here we show that leptin modulates GABAergic transmission onto developing CA3 pyramidal cells of newborn rats. Specifically, leptin induces a long-lasting potentiation (LLP-GABAA of miniature GABAA receptor-mediated postsynaptic current (GABAA-PSC frequency. Leptin also increases the amplitude of evoked GABAA-PSCs in a subset of neurons along with a decrease in the coefficient of variation and no change in the paired-pulse ratio, pointing to an increased recruitment of functional synapses. Adding pharmacological blockers to the recording pipette showed that the leptin-induced LLP-GABAA requires postsynaptic calcium released from internal stores, as well as postsynaptic MAPK/ERK kinases 1 and/or 2 (MEK1/2, phosphoinositide 3 kinase (PI3K and calcium-calmodulin kinase kinase (CaMKK. Finally, study of CA3 pyramidal cells in leptin-deficient ob/ob mice revealed a reduction in the basal frequency of miniature GABAA-PSCs compared to wild type littermates. In addition, presynaptic GAD65 immunostaining was reduced in the CA3 stratum pyramidale of mutant animals, both results converging to suggest a decreased number of functional GABAergic synapses in ob/ob mice. Overall, these results show that leptin potentiates and promotes the development of GABAergic synaptic transmission in the developing hippocampus likely via an increase in the number of functional synapses, and provide insights into the intracellular pathways mediating this effect. This study further extends the scope of leptin’s neurotrophic action to a key regulator of hippocampal development and function, namely GABAergic transmission.

  10. The hippocampus and the regulation of human food intake.

    Science.gov (United States)

    Stevenson, Richard J; Francis, Heather M

    2017-10-01

    Human and animal data suggest that the hippocampus plays certain roles in regulating food intake. However, its actual role may be far broader than currently envisaged, a claim suggested by the centrality of the hippocampus to so many aspects of human/animal cognition. Understanding these ingestion-related functions is especially significant. This is because some degree of hippocampal impairment may be quite common, resulting for example from a Western-style diet, insomnia, diabetes, and depression-among many other causes. One potential consequence of hippocampal impairment could be a loosening of food intake regulation, leading in the longer-term to weight gain and its health-related impacts. Here we review known, suspected and newly hypothesized hippocampal-dependent functions involved in regulating human food intake: (a) declarative memory processes, and their use in explicitly evaluating when, what and how much to eat; (b) interoception, as it relates to hunger, fullness and thirst; (c) inhibitory processes, especially as applied to physiological state, place, and time, and their role in modulating memory retrieval; (d) craving and imagery for food; (e) perception of time and its role in preparing the body for food intake and estimating meal length; (f) trace conditioning and nutrient-related learning; and (g) inhibition of the hypothalamic-pituitary-adrenal stress response and stress-related eating. For each we present evidence for hippocampal involvement, describe the putative regulatory role, and the hypothesized effects of hippocampal impairment. We conclude that the hippocampus is intimately involved in regulating human food intake via multiple interconnected pathways, many of which are unstudied and understudied. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  11. Hippocampus sparing in whole-brain radiotherapy. A review

    Energy Technology Data Exchange (ETDEWEB)

    Oskan, F. [University of Munich, Department of Radiation Oncology and CCC Neuro-Oncology, Munich (Germany); Saarland University Medical Center, Department of Radiation Oncology, Homburg/Saar (Germany); Ganswindt, U.; Schwarz, S.B.; Manapov, F.; Belka, C.; Niyazi, M. [University of Munich, Department of Radiation Oncology and CCC Neuro-Oncology, Munich (Germany)

    2014-04-15

    Radiation treatment techniques for whole-brain radiation therapy (WBRT) have not changed significantly since development of the procedure. However, the recent development of novel techniques such as intensity-modulated radiation therapy (IMRT), volumetric-modulated arc therapy (VMAT) and helical tomotherapy, as well as an increasing body of evidence concerning neural stem cells (NSCs) have altered the conventional WBRT treatment paradigm. In this regard, hippocampus-sparing WBRT is a novel technique that aims to spare critical hippocampus regions without compromising tumour control. Published data on this new technique are limited to planning and feasibility studies; data on patient outcome are still lacking. However, several prospective trials to analyse the feasibility of this technique and to document clinical outcome in terms of reduced neurotoxicity are ongoing. (orig.) [German] Die Technik der Ganzhirnbestrahlung (''whole-brain radiation therapy'', WBRT) hat sich seit der Entwicklung nicht wesentlich veraendert. Allerdings stellten die Neuentwicklung von Techniken wie die intensitaetsmodulierte Strahlentherapie (IMRT), die volumenmodulierte Arc-Therapie (VMAT) oder die helikale Tomotherapie sowie immer groesseres Wissen ueber das neurale Stammzellkompartiment (NSCs) das herkoemmliche Ganzhirn-Paradigma in Frage. Die hippocampusschonende Ganzhirnbestrahlung ist eine neuartige Technik, welche die kritische Region des Hippocampus schont, ohne die Tumorkontrolle zu gefaehrden. Ueber diese Technik gibt es bisher nur eine begrenzte Datenlage im Sinne von Planungs- und Machbarkeitsstudien. Klinische Daten bzgl. der Behandlungsergebnisse fehlen nach wie vor, aber einige prospektive Studien sind im Gange, um nicht nur die Machbarkeit zu belegen, sondern auch das klinische Outcome im Sinne einer verringerten Neurotoxizitaet nachzuweisen. (orig.)

  12. Conscious Experience and Episodic Memory: Hippocampus at the Crossroads

    Directory of Open Access Journals (Sweden)

    Ralf-Peter eBehrendt

    2013-05-01

    Full Text Available If an instance of conscious experience of the seemingly objective world around us could be regarded as a newly formed event memory, much as an instance of mental imagery has the content of a retrieved event memory, and if, therefore, the stream of conscious experience could be seen as evidence for ongoing formation of event memories that are linked into episodic memory sequences, then unitary conscious experience could be defined as a symbolic representation of the pattern of hippocampal neuronal firing that encodes an event memory – a theoretical stance that may shed light into the mind-body and binding problems in consciousness research. Exceedingly detailed symbols that describe patterns of activity rapidly self-organizing, at each cycle of the θ rhythm, in the hippocampus are instances of unitary conscious experience that jointly constitute the stream of consciousness. Integrating object information (derived from the ventral visual stream and orbitofrontal cortex with contextual emotional information (from the anterior insula and spatial environmental information (from the dorsal visual stream, the hippocampus rapidly forms event codes that have the informational content of objects embedded in an emotional and spatiotemporally extending context. Event codes, formed in the CA3-dentate network for the purpose of their memorization, are not only contextualized but also allocentric representations, similarly to conscious experiences of events and objects situated in a seemingly objective and observer-independent framework of phenomenal space and time. Conscious perception is likely to be related to more fleeting and seemingly internal forms of conscious experience, such as autobiographical memory recall, mental imagery, including goal anticipation, and to other forms of externalized conscious experience, namely dreaming and hallucinations; and evidence pointing to an important contribution of the hippocampus to these conscious phenomena will

  13. The hippocampus is necessary for enhancements and impairments of learning following stress

    OpenAIRE

    Bangasser, Debra A; Shors, Tracey J

    2007-01-01

    The hippocampus is often considered to be an important site for stress and learning interactions; however, it has never been demonstrated whether these effects require the hippocampus. In the current study, hippocampal lesions prevented both enhancements of learning after stress in male rats and impairments of learning after stress in female rats without disrupting learning itself in either sex. Thus, the hippocampus is necessary for modifying learning in males and females after acute stressf...

  14. A Critical Role for the Hippocampus in the Valuation of Imagined Outcomes

    OpenAIRE

    Lebreton, Maël; Bertoux, Maxime; Boutet, Claire; Lehericy, Stéphane; Dubois, Bruno; Fossati, Philippe; Pessiglione, Mathias

    2013-01-01

    International audience; Many choice situations require imagining potential outcomes, a capacity that was shown to involve memory brain regions such as the hippocampus. We reasoned that the quality of hippocampus-mediated simulation might therefore condition the subjective value assigned to imagined outcomes. We developed a novel paradigm to assess the impact of hippocampus structure and function on the propensity to favor imagined outcomes in the context of intertemporal choices. The ecologic...

  15. Evidencing a place for the hippocampus within the core scene processing network.

    Science.gov (United States)

    Hodgetts, C J; Shine, J P; Lawrence, A D; Downing, P E; Graham, K S

    2016-11-01

    Functional neuroimaging studies have identified several "core" brain regions that are preferentially activated by scene stimuli, namely posterior parahippocampal gyrus (PHG), retrosplenial cortex (RSC), and transverse occipital sulcus (TOS). The hippocampus (HC), too, is thought to play a key role in scene processing, although no study has yet investigated scene-sensitivity in the HC relative to these other "core" regions. Here, we characterised the frequency and consistency of individual scene-preferential responses within these regions by analysing a large dataset (n = 51) in which participants performed a one-back working memory task for scenes, objects, and scrambled objects. An unbiased approach was adopted by applying independently-defined anatomical ROIs to individual-level functional data across different voxel-wise thresholds and spatial filters. It was found that the majority of subjects had preferential scene clusters in PHG (max = 100% of participants), RSC (max = 76%), and TOS (max = 94%). A comparable number of individuals also possessed significant scene-related clusters within their individually defined HC ROIs (max = 88%), evidencing a HC contribution to scene processing. While probabilistic overlap maps of individual clusters showed that overlap "peaks" were close to those identified in group-level analyses (particularly for TOS and HC), inter-individual consistency varied across regions and statistical thresholds. The inter-regional and inter-individual variability revealed by these analyses has implications for how scene-sensitive cortex is localised and interrogated in functional neuroimaging studies, particularly in medial temporal lobe regions, such as the HC. Hum Brain Mapp 37:3779-3794, 2016. © 2016 Wiley Periodicals, Inc. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

  16. The hippocampus and exploration: dynamically evolving behavior and neural representations

    Science.gov (United States)

    Johnson, Adam; Varberg, Zachary; Benhardus, James; Maahs, Anthony; Schrater, Paul

    2012-01-01

    We develop a normative statistical approach to exploratory behavior called information foraging. Information foraging highlights the specific processes that contribute to active, rather than passive, exploration and learning. We hypothesize that the hippocampus plays a critical role in active exploration through directed information foraging by supporting a set of processes that allow an individual to determine where to sample. By examining these processes, we show how information directed information foraging provides a formal theoretical explanation for the common hippocampal substrates of constructive memory, vicarious trial and error behavior, schema-based facilitation of memory performance, and memory consolidation. PMID:22848196

  17. The hippocampus and exploration: dynamically evolving behavior and neural representations

    Directory of Open Access Journals (Sweden)

    Adam eJohnson

    2012-07-01

    Full Text Available We develop a normative statistical approach to exploratory behavior called information foraging. Information foraging highlights the specific processes that contribute to active, rather than passive, exploration and learning. We hypothesize that the hippocampus plays a critical role in active exploration through directed information foraging by supporting a set of processes that allow an individual to determine where to sample. By examining these processes, we show how information directed information foraging provides a formal theoretical explanation for the common hippocampal substrates of constructive memory, vicarious trial and error behavior, schema-based facilitation of memory performance, and memory consolidation.

  18. Muscarinic receptor compensation in hippocampus of alzheimer patients

    International Nuclear Information System (INIS)

    Nordberg, A.; Larsson, C.; Adolfsson, R.; Alafuzoff, I.; Winblad, B.

    1983-01-01

    The activity of the acetylcholine synthesizing enzyme choline acetyltransferase (ChAT) (presynaptic marker) and number of muscarine-like receptor binding sites have been measured in the hippocampus from eight individuals with senile dementia of Alzheimer type (SDAT) and ten controls. A negative correlation (r=0.80; p<0.05) was found between the ChAT activity and the number of muscarine-like receptors in the SDAT group but not in the controls. The findings might indicate an ongoing compensatory receptor mechanism as a response to changes in presynaptic cholinergic activity. (Author)

  19. Nicotinic Receptors in the Dorsal and Ventral Hippocampus Differentially Modulate Contextual Fear Conditioning

    Science.gov (United States)

    Kenney, Justin W.; Raybuck, Jonathan D.; Gould, Thomas J.

    2012-01-01

    Nicotine administration alters various forms of hippocampus-dependent learning and memory. Increasing work has found that the dorsal and ventral hippocampus differentially contribute to multiple behaviors. Thus, the present study examined whether the effects of nicotine in the dorsal and ventral hippocampus have distinct influences on contextual fear learning in male C57BL/6J mice. Direct infusion of nicotine into the dorsal hippocampus resulted in an enhancement of contextual fear learning, whereas nicotine infused into the ventral hippocampus resulted in deficits. Nicotine infusions into the ventral hippocampus did not alter hippocampus-independent cued fear conditioning or time spent in the open arm of the elevated plus maze, a measure of anxiety, suggesting the effects are due to alterations in contextual learning and not other general processes. Finally, results from using direct infusions of MLA, a low-affinity α7 nicotinic acetylcholine receptor (nAChR) antagonist, in conjunction with systemic nicotine, provide evidence that α7-nAChRs in the ventral hippocampus mediate the detrimental effect of ventral hippocampal nicotine on contextual fear learning. These results suggest that with systemic nicotine administration, competition exists between the dorsal and ventral hippocampus for behavioral control over contextual learning. PMID:22271264

  20. Choline acetyltransferase in the hippocampus is associated with learning strategy preference in adult male rats.

    Science.gov (United States)

    Hawley, Wayne R; Witty, Christine F; Daniel, Jill M; Dohanich, Gary P

    2015-08-01

    One principle of the multiple memory systems hypothesis posits that the hippocampus-based and striatum-based memory systems compete for control over learning. Consistent with this notion, previous research indicates that the cholinergic system of the hippocampus plays a role in modulating the preference for a hippocampus-based place learning strategy over a striatum-based stimulus--response learning strategy. Interestingly, in the hippocampus, greater activity and higher protein levels of choline acetyltransferase (ChAT), the enzyme that synthesizes acetylcholine, are associated with better performance on hippocampus-based learning and memory tasks. With this in mind, the primary aim of the current study was to determine if higher levels of ChAT and the high-affinity choline uptake transporter (CHT) in the hippocampus were associated with a preference for a hippocampus-based place learning strategy on a task that also could be solved by relying on a striatum-based stimulus--response learning strategy. Results confirmed that levels of ChAT in the dorsal region of the hippocampus were associated with a preference for a place learning strategy on a water maze task that could also be solved by adopting a stimulus-response learning strategy. Consistent with previous studies, the current results support the hypothesis that the cholinergic system of the hippocampus plays a role in balancing competition between memory systems that modulate learning strategy preference. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Convergence of posteriors for discretized log Gaussian Cox processes

    DEFF Research Database (Denmark)

    Waagepetersen, Rasmus Plenge

    2004-01-01

    In Markov chain Monte Carlo posterior computation for log Gaussian Cox processes (LGCPs) a discretization of the continuously indexed Gaussian field is required. It is demonstrated that approximate posterior expectations computed from discretized LGCPs converge to the exact posterior expectations...... when the cell sizes of the discretization tends to zero. The effect of discretization is studied in a data example....

  2. Topography of The Posterior Communicating Artery in a Kenyan ...

    African Journals Online (AJOL)

    pattern of the posterior communication artery in a Kenyan population. Materials and Methods. Eighty four posterior communicating arteries obtained from Depart- ment of Human Anatomy were studied. The configuration and number of branches in each third and length of the longest perforator free zone of the posterior ...

  3. Study of Posterior Cerebral Artery in Human Cadaveric Brain

    Directory of Open Access Journals (Sweden)

    S. A. Gunnal

    2015-01-01

    Full Text Available Objective. Basilar artery (BA terminates in right and left posterior cerebral arteries (PCAs. Each PCA supplies respective occipital lobe of the cerebrum. The present study is designed to know the morphology, morphometry, branching pattern, and symmetry of PCA. Methods. The study included 340 PCAs dissected from 170 human cadaveric brains. Results. Morphological variations of P1 segment included, aplasia (2.35%, hypoplasia (5.29%, duplication (2.35%, fenestration (1.17%, and common trunk shared with SCA (1.76%. Morphological variations of origin of P2 segment included direct origin of it from BA (1.17% and ICA (2.35%. Unusually, two P2 segments, each arising separately from BA and ICA, were observed in 1.17%. Unilateral two P2 segments from CW were found in 0.58%. Morphological variations of course of P2 were duplication (0.58%, fenestration (0.58%, and aneurysm (1.76%. Unilateral P2 either adult or fetal was seen in 4.71%. The group II branching pattern was found to be most common. Asymmetry of P2 was 40%. Morphometry of P2 revealed mean length of 52 mm and mean diameter of 2.7 mm. Conclusion. The present study provides the complete anatomical description of PCA regarding morphology, morphometry, symmetry, and its branching pattern. Awareness of these variations is likely to be useful in cerebrovascular procedures.

  4. Analysis digital panoramic radiograph about positions root of maxillary posterior teeth with maxillary sinus floor

    Directory of Open Access Journals (Sweden)

    Aprilia Dian Pertiwi

    2016-11-01

    Full Text Available Introduction: Maxillary sinus floor is a part of the alveolar bone adjacent to the apex of the posterior maxillary teeth that often causes complications in dentistry. Anatomical relationship between the maxillary posterior tooth root and the maxillary sinus floor can be obtained by panoramic radiograph.  The purpose of this study is to analysis digital panoramic radiograph about positions root of maxillary posterior teeth’s with  maxillary sinus floor by age and gender using. Methods: Research method is descriptive with purposive sampling technique. Study population was taken from archives of patient’s digital panoramic radiograph in Radiography Installation from January to March 2016. 88 samples were obtained from 207 digital panoramic radiographs archives. Results: The result showed that type 3 was dominated by P1 (86.8% right, 88.2% left, type 2 is dominated by P2 (24.7% right, 21% left, type 1 is dominated by M2 in the right (31.2% and M1 in the left (38.1%. Conclusion: This study concludes that overall, the most commonly found was type 3. Based on the age, type 1 majority occurs in age group of above 49 years old; type 2 in age group of 40-49 years old; and type 3 in age group 30-39 years old, 40-49 years old, and above 49 years old. By gender, type 1 and type 2 are more common in males, while type 3 is more common in female.

  5. A new method of evaluating posterior occlusion and its relation to posttreatment occlusal changes.

    Science.gov (United States)

    Parkinson, C E; Buschang, P H; Behrents, R G; Throckmorton, G S; English, J D

    2001-11-01

    The purpose of this study was to assess the relationship between posterior occlusion and posttreatment changes in other occlusal variables. Pretreatment (T1), posttreatment (T2), and postretention (T3) records were obtained for 49 Class I (n = 23) and Class II (n = 26) extraction cases. Overbite, overjet, mandibular incisor irregularity, right and left molar deviations, midline deviation, and mandibular arch length were measured, and occlusal registrations were made of each set of dental casts. The proximity of posterior occlusal surfaces was measured as the contact or near-contact areas at or below 300 microm thickness, based on the optical densities of scanned images of the posterior occlusal registrations. The treatment changes for overbite, overjet, right and left molar deviation, and arch length were significantly greater in the Class II group, and the reductions in incisor irregularity were greater in the Class I group. No other class differences were found. Overbite, overjet, and incisor irregularity increased after treatment, and arch length continued to decrease, with no significant class differences. Contact and near-contact areas at or below 300 microm constituted 7% of the functional occlusal table for both classes at the end of treatment, having decreased significantly in both groups (21% in Class I and 29% in Class II) during treatment. Because contact and near-contact areas increased in some patients and decreased in others, there were no significant posttreatment changes. Negative correlations were found between contact and near-contact areas at T2 and changes in overjet from T2 to T3, and between contact and near-contact areas at T3 and changes in overbite from T2 to T3. No relationships were found between posterior contact and near-contact area and incisor irregularity. We concluded that (1) the area of actual and near contacts at or below 300 microm decreased significantly with treatment, indicating that, despite excellent treatment results by

  6. [Lesion of extrahippocampal cortices of left medial temporal lobe: a case report].

    Science.gov (United States)

    Spada, J A; Galíndez, C; Spada, A

    The cortex of medial temporal lobe is a group of different allocortical fields which included the hippocampal formation (dentate gyrus, hippocampus proper, and subicular complex) and extrahippocampal cortices (entorhinal, perirhinal, and parahippocampal). It is widely accepted that both of them play an important role in memory process. In humans, several reports indicates that damage to the hippocampus alone would lead to a clinically significant amnesia; when the injuries are more extensive others cognitive disorders, as those related to visual sphere, make worse the clinic picture, and some of these cases were reported as associative visual agnosias. Nevertheless, although evidence from animal studies points to the importance of the extrahippocampal medial temporal lobe cortices in order to recognise visual stimuli, such involvement has not been demonstrated in humans. A 44 year-old male who consulted us because they had lost about of '80% of his vision' after a stroke. Ophthalmological examination was entirely within normal limits, but neuropsychological test put in evidence difficulties in the visuo-verbal naming, discrimination of superposed images, recognition of faces and, mainly, in the test of immediate and deferred visual memory. Anterograde memory impairment was also revealed. Magnetic resonance imaging showed a lesion of left entorhinal, perirhinal and parahippocampal cortices. We suggest, in relation to anatomical evidences, that isolation of hippocampus is responsible for symptomatollogy of our patient.

  7. [Application of acetabular tridimensional memory alloy-fixation system in treatment of posterior wall acetabular fracture with posterior dislocation of hip].

    Science.gov (United States)

    Cao, Liehu; Zhang, Chuncai; Su, Jiacan; Zhang, Wencai; Liu, Xinwei

    2009-09-01

    To investigate the clinical effect of the acetabular tridimensional memory alloy-fixation system (ATMFS) in treatment of posterior wall acetabular fractures with posterior dislocation of hip. From January 2004 to February 2006, 15 cases of posterior wall acetabular fracture with posterior dislocation of hip were treated. There were 11 males and 4 females, aged 21-68 years old with an average of 43.5 years old. Injury was caused by traffic accident in 8 cases, by falling from height in 5 cases and others in 2 cases. The locations were the left hip in 9 cases and the right hip in 6 cases. According to Thompson-Epstein' fracture classification, there were 6 cases of type II, 5 cases of type III, 2 cases of type IV and 2 cases of type V. Imaging showed the acetabular articular surface displacement of 2-5 mm (mean 3 mm). The time from injury to hospitalization was 6 hours to 2 weeks(mean 1.5 days). Skeletal traction on femoral condyle was given, manual reduction was performed in 12 patients and intra-operative reduction in 3 cases. ATMFS was used after 2-7 days of hospitalization, and 4 cases received autologous free ilium because of bone defect. The operative time was 90-390 minutes with an average of 210 minutes. Intraoperative blood loss was 350-2 500 mL with an average of 360 mL. The hospitalization days of the patients ranged from 7 to 21 days(mean 10 days). Epidermal infection occurred and was cured after symptomatic management in 1 case. Other incisions healed by first intention. No deep infections, pulmonary embolism, deep venous thrombosis and other complications occurred. The patients were followed up 1 to 3 years with an average of 1.6 years. Ischemic necrosis of femoral head occurred in 1 case. Heterotopic ossification in grade II occurred in 1 case. The hip function was still good without special treatment. According to Matta's X-ray fracture reduction assessment, the results were excellent in 7 cases, good in 5 cases, fair in 2 cases, and poor in 1 case

  8. Functionally distinct contributions of the anterior and posterior putamen during sublexical and lexical reading

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    Marion eOberhuber

    2013-11-01

    Full Text Available Previous studies have investigated orthographic-to-phonological mapping during reading by comparing brain activation for (1 reading words to object naming, or (2 reading pseudowords (e.g. phume to words (e.g. plume. Here we combined both approaches to provide new insights into the underlying neural mechanisms. In fMRI data from 25 healthy adult readers, we first identified activation that was greater for reading words and pseudowords relative to picture and color naming. The most significant effect was observed in the left putamen, extending to both anterior and posterior borders. Second, consistent with previous studies, we show that both the anterior and posterior putamen are involved in articulating speech with greater activation during our overt speech production tasks (reading, repetition, object naming and color naming than silent one-back-matching on the same stimuli. Third, we compared putamen activation for words versus pseudowords during overt reading and auditory repetition. This revealed that the anterior putamen was most activated by reading pseudowords, whereas the posterior putamen was most activated by words irrespective of whether the task was reading words or auditory word repetition. The pseudoword effect in the anterior putamen is consistent with prior studies that associated this region with the initiation of novel sequences of movements. In contrast, the heightened word response in the posterior putamen is consistent with other studies that associated this region with memory guided movement. Our results illustrate how the functional dissociation between the anterior and posterior putamen supports sublexical and lexical processing during reading.

  9. Posterior-Only Circumferential Decompression and Reconstruction in the Surgical Management of Lumbar Vertebral Osteomyelitis.

    Science.gov (United States)

    Skovrlj, Branko; Guzman, Javier Z; Caridi, John; Cho, Samuel K

    2016-02-01

    Study Design Case report. Objective The purpose of this report is to discuss the surgical management of lumbar vertebral osteomyelitis with a spinal epidural abscess (SEA) and present a single-stage, posterior-only circumferential decompression and reconstruction with instrumentation using an expandable titanium cage and without segmental nerve root sacrifice as an option in the treatment of this disease process. Methods We report a 42-year-old man who presented with 3 days of low back pain and chills who rapidly decompensated with severe sepsis following admission. Magnetic resonance imaging of his lumbosacral spine revealed intramuscular abscesses of the left paraspinal musculature and iliopsoas with SEA and L4 vertebral body involvement. The patient failed maximal medical treatment, which necessitated surgical treatment as a last resort for infectious source control. He underwent a previously undescribed procedure in the setting of SEA: a single-stage, posterior-only approach for circumferential decompression and reconstruction of the L4 vertebral body with posterior segmental instrumented fixation. Results After the surgery, the patient's condition gradually improved; however, he suffered a wound dehiscence necessitating a surgical exploration and deep wound debridement. Six months after the surgery, the patient underwent a revision surgery for adjacent-level pseudarthrosis. At 1-year follow-up, the patient was pain-free and off narcotic pain medication and had returned to full activity. Conclusion This patient is the first reported case of lumbar osteomyelitis with SEA treated surgically with a single-stage, posterior-only circumferential decompression and reconstruction with posterior instrumentation. Although this approach is more technically challenging, it presents another viable option for the treatment of lumbar vertebral osteomyelitis that may reduce the morbidity associated with an anterior approach.

  10. High Plasticity of New Granule Cells in the Aging Hippocampus

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    Mariela F. Trinchero

    2017-10-01

    Full Text Available Summary: During aging, the brain undergoes changes that impair cognitive capacity and circuit plasticity, including a marked decrease in production of adult-born hippocampal neurons. It is unclear whether development and integration of those new neurons are also affected by age. Here, we show that adult-born granule cells (GCs in aging mice are scarce and exhibit slow development, but they display a remarkable potential for structural plasticity. Retrovirally labeled 3-week-old GCs in middle-aged mice were small, underdeveloped, and disconnected. Neuronal development and integration were accelerated by voluntary exercise or environmental enrichment. Similar effects were observed via knockdown of Lrig1, an endogenous negative modulator of neurotrophin receptors. Consistently, blocking neurotrophin signaling by Lrig1 overexpression abolished the positive effects of exercise. These results demonstrate an unparalleled degree of plasticity in the aging brain mediated by neurotrophins, whereby new GCs remain immature until becoming rapidly recruited to the network by activity. : Trinchero et al. show that development of new granule cells born in the adult hippocampus is strongly influenced by age. In the aging hippocampus, new neurons remain immature for prolonged intervals, yet voluntary exercise triggers their rapid growth and functional synaptogenesis. This extensive structural remodeling is mediated by neurotrophins. Keywords: adult neurogenesis, dentate gyrus, functional integration, neurotrophins, synaptogenesis, exercise

  11. Overnight Sleep Enhances Hippocampus-Dependent Aspects of Spatial Memory.

    Science.gov (United States)

    Nguyen, Nam D; Tucker, Matthew A; Stickgold, Robert; Wamsley, Erin J

    2013-07-01

    Several studies have now demonstrated that spatial information is processed during sleep, and that posttraining sleep is beneficial for human navigation. However, it remains unclear whether the effects of sleep are primarily due to consolidation of cognitive maps, or alternatively, whether sleep might also affect nonhippocampal aspects of navigation (e.g., speed of motion) involved in moving through a virtual environment. Participants were trained on a virtual maze navigation task (VMT) and then given a memory test following either a day of wakefulness or a night of sleep. Subjects reported to the laboratory for training at either 10:00am or 10:00pm, depending on randomly assigned condition, and were tested 11 h later. Overnight subjects slept in the laboratory with polysomnography. A hospital-based academic sleep laboratory. Thirty healthy college student volunteers. N/A. Point-by-point position data were collected from the VMT. Analysis of the movement data revealed a sleep-dependent improvement in maze completion time (P sleep benefitted performance, not because subjects moved faster through the maze, but because they were more accurate in navigating to the goal. These findings suggest that sleep enhances participants' knowledge of the spatial layout of the maze, contributing to the consolidation of hippocampus-dependent spatial information. Nguyen ND; Tucker MA; Stickgold R; Wamsley EJ. Overnight sleep enhances hippocampus-dependent aspects of spatial memory. SLEEP 2013;36(7):1051-1057.

  12. Donor/recipient enhancement of memory in rat hippocampus

    Science.gov (United States)

    Deadwyler, Sam A.; Berger, Theodore W.; Sweatt, Andrew J.; Song, Dong; Chan, Rosa H. M.; Opris, Ioan; Gerhardt, Greg A.; Marmarelis, Vasilis Z.; Hampson, Robert E.

    2013-01-01

    The critical role of the mammalian hippocampus in the formation, translation and retrieval of memory has been documented over many decades. There are many theories of how the hippocampus operates to encode events and a precise mechanism was recently identified in rats performing a short-term memory task which demonstrated that successful information encoding was promoted via specific patterns of activity generated within ensembles of hippocampal neurons. In the study presented here, these “representations” were extracted via a customized non-linear multi-input multi-output (MIMO) mathematical model which allowed prediction of successful performance on specific trials within the testing session. A unique feature of this characterization was demonstrated when successful information encoding patterns were derived online from well-trained “donor” animals during difficult long-delay trials and delivered via online electrical stimulation to synchronously tested naïve “recipient” animals never before exposed to the delay feature of the task. By transferring such model-derived trained (donor) animal hippocampal firing patterns via stimulation to coupled naïve recipient animals, their task performance was facilitated in a direct “donor-recipient” manner. This provides the basis for utilizing extracted appropriate neural information from one brain to induce, recover, or enhance memory related processing in the brain of another subject. PMID:24421759

  13. THEORETICAL REVIEW The Hippocampus, Time, and Memory Across Scales

    Science.gov (United States)

    Howard, Marc W.; Eichenbaum, Howard

    2014-01-01

    A wealth of experimental studies with animals have offered insights about how neural networks within the hippocampus support the temporal organization of memories. These studies have revealed the existence of “time cells” that encode moments in time, much as the well-known “place cells” map locations in space. Another line of work inspired by human behavioral studies suggests that episodic memories are mediated by a state of temporal context that changes gradually over long time scales, up to at least a few thousand seconds. In this view, the “mental time travel” hypothesized to support the experience of episodic memory corresponds to a “jump back in time” in which a previous state of temporal context is recovered. We suggest that these 2 sets of findings could be different facets of a representation of temporal history that maintains a record at the last few thousand seconds of experience. The ability to represent long time scales comes at the cost of discarding precise information about when a stimulus was experienced—this uncertainty becomes greater for events further in the past. We review recent computational work that describes a mechanism that could construct such a scale-invariant representation. Taken as a whole, this suggests the hippocampus plays its role in multiple aspects of cognition by representing events embedded in a general spatiotemporal context. The representation of internal time can be useful across nonhippocampal memory systems. PMID:23915126

  14. Local Klotho enhances neuronal progenitor proliferation in the adult hippocampus.

    Science.gov (United States)

    Salech, Felipe; Varela-Nallar, Lorena; Arredondo, Sebastián B; Bustamante, Daniel B; Andaur, Gabriela A; Cisneros, Rodrigo; Ponce, Daniela P; Ayala, Patricia; Inestrosa, Nibaldo C; Valdés, José L; Behrens, María I; Couve, Andrés

    2017-12-30

    Klotho is an aging-related protein associated with hippocampal cognitive performance in mammals. Klotho regulates progenitor cell proliferation in non-neuronal tissues, but its role in adult hippocampal neurogenesis (AHN) has not been explored. Klotho expression in the adult mouse hippocampus was examined by immunofluorescence and PCR. AHN was evaluated in the hippocampus of klotho knock-out mice (KO), klotho KO/vitamin D-receptor mutant mice, and in a model of local klotho hippocampal knockdown. The recombinant Klotho effect on proliferation was measured in mouse-derived hippocampal neural progenitor cells. Hippocampal-dependent memory was assessed by a dry-land version of the Morris water maze. Klotho was expressed in the granular cell layer of the adult Dentate Gyrus. AHN was increased in klotho KO mice, but not in klotho KO/vitamin D-receptor mutant mice. Inversely, local downregulation of hippocampal Klotho diminished AHN. Recombinant Klotho increased the proliferation rate of neural progenitors. Downregulation of hippocampal Klotho correlated with a decreased performance in hippocampal dependent memory. These results suggest that Klotho directly participates in regulating AHN. Our observations indicate that Klotho promotes proliferation, AHN and hippocampal dependent cognition. Increased neurogenesis in klotho KO mice may be secondary to the activation of other pathways altered in the model, such as vitamin D. © The Author(s) 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. The hippocampus facilitates integration within a symbolic field.

    Science.gov (United States)

    Cornelius, John Thor

    2017-10-01

    This paper attempts to elaborate a fundamental brain mechanism involved in the creation and maintenance of symbolic fields of thought. It will integrate theories of psychic spaces as explored by Donald Winnicott and Wilfred Bion with the neuroscientific examinations of those with bilateral hippocampal injury to show how evidence from both disciplines sheds important light on this aspect of mind. Possibly originating as a way of maintaining an oriented, first person psychic map, this capacity allows individuals a dynamic narrative access to a realm of layered elements and their connections. If the proposed hypothesis is correct, the hippocampus facilitates the integration of this symbolic field of mind, where narrative forms of thinking, creativity, memory, and dreaming are intertwined. Without the hippocampus, there is an inability to engage many typical forms of thought itself. Also, noting the ways these individuals are not impaired supports theories about other faculties of mind, providing insight into their possible roles within human thought. The evidence of different systems working in conjunction with the symbolic field provides tantalizing clues about these fundamental mechanisms of brain and mind that are normally seamlessly integrated, and hints at future areas of clinical and laboratory research, both within neuroscience and psychoanalysis. © 2017 The Authors. The International Journal of Psychoanalysis published by John Wiley & Sons Ltd on behalf of Institute of Psychoanalysis.

  16. Proteomic Analysis of Rat Hippocampus under Simulated Microgravity

    Science.gov (United States)

    Wang, Yun; Li, Yujuan; Zhang, Yongqian; Liu, Yahui; Deng, Yulin

    It has been found that microgravity may lead to impairments in cognitive functions performed by CNS. However, the exact mechanism of effects of microgravity on the learning and memory function in animal nervous system is not elucidated yet. Brain function is mainly mediated by membrane proteins and their dysfunction causes degeneration of the learning and memory. To induce simulated microgravity, the rat tail suspension model was established. Comparative O (18) labeling quantitative proteomic strategy was applied to detect the differentially expressed proteins in rat brain hippocampus. The proteins in membrane fraction from rat hippocampus were digested by trypsin and then the peptides were separated by off-gel for the first dimension with 24 wells device encompassing the pH range of 3 - 10. An off-gel fraction was subjected into LC-ESI-QTOF in triplicate. Preliminary results showed that nearly 77% of the peptides identified were specific to one fraction. 676 proteins were identified among which 108 proteins were found differentially expressed under simulated microgravity. Using the KOBAS server, many enriched pathways, such as metabolic pathway, synaptic vesicle cycle, endocytosis, calcium signaling pathway, and SNAREs pathway were identified. Furthermore, it has been found that neurotransmitter released by Ca (2+) -triggered synaptic vesicles fusion may play key role in neural function. Rab 3A might inhibit the membrane fusion and neurotransmitter release. The protein alteration of the synaptic vesicle cycle may further explain the effects of microgravity on learning and memory function in rats. Key words: Microgravity; proteomics; synaptic vesicle; O (18) ({}) -labeling

  17. Reliable activation of immature neurons in the adult hippocampus.

    Directory of Open Access Journals (Sweden)

    Lucas A Mongiat

    Full Text Available Neurons born in the adult dentate gyrus develop, mature, and connect over a long interval that can last from six to eight weeks. It has been proposed that, during this period, developing neurons play a relevant role in hippocampal signal processing owing to their distinctive electrical properties. However, it has remained unknown whether immature neurons can be recruited into a network before synaptic and functional maturity have been achieved. To address this question, we used retroviral expression of green fluorescent protein to identify developing granule cells of the adult mouse hippocampus and investigate the balance of afferent excitation, intrinsic excitability, and firing behavior by patch clamp recordings in acute slices. We found that glutamatergic inputs onto young neurons are significantly weaker than those of mature cells, yet stimulation of cortical excitatory axons elicits a similar spiking probability in neurons at either developmental stage. Young neurons are highly efficient in transducing ionic currents into membrane depolarization due to their high input resistance, which decreases substantially in mature neurons as the inward rectifier potassium (Kir conductance increases. Pharmacological blockade of Kir channels in mature neurons mimics the high excitability characteristic of young neurons. Conversely, Kir overexpression induces mature-like firing properties in young neurons. Therefore, the differences in excitatory drive of young and mature neurons are compensated by changes in membrane excitability that render an equalized firing activity. These observations demonstrate that the adult hippocampus continuously generates a population of highly excitable young neurons capable of information processing.

  18. Effects of diaphragm stretching on posterior chain muscle kinematics and rib cage and abdominal excursion: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Francisco J. González-Álvarez

    2016-01-01

    Full Text Available ABSTRACT Background Few studies have explored the effects of stretching techniques on diaphragm and spine kinematics. Objective To determine whether the application of diaphragm stretching resulted in changes in posterior chain muscle kinematics and ribcage and abdominal excursion in healthy subjects. Method Eighty healthy adults were included in this randomized clinical trial. Participants were randomized into two groups: the experimental group, which received a diaphragmatic stretching technique, or the placebo group, which received a sham-ultrasound procedure. The duration of the technique, the position of participants, and the therapist who applied the technique were the same for both treatments. Participant assessment (cervical range of movement, lumbar flexibility, flexibility of the posterior chain, and rib cage and abdominal excursion was performed at baseline and immediately after the intervention by a blinded assessor. Results The mean between-group difference [95% CI] for the ribcage excursion after technique at xiphoid level was 2.48 [0.97 to 3.99], which shows significant differences in this outcome. The remaining between-group analysis showed significant differences in cervical extension, right and left flexion, flexibility of the posterior chain, and ribcage excursion at xiphoid level (p<0.05 in favor of the experimental group. Conclusion Diaphragm stretching generates a significant improvement in cervical extension, right and left cervical flexion, flexibility of the posterior chain, and ribcage excursion at xiphoid level compared to a placebo technique in healthy adults.

  19. Fractional arm weakness as presentation of stroke due to posterior borderzone infarct: A report of two cases

    OpenAIRE

    Hassan, Kaukab Maqbool

    2010-01-01

    A 41-year-old male presented with acute onset weakness of the left hand. Magnetic resonance imaging (MRI) of the brain showed hyperacute infarct in the right middle cerebral artery (MCA)-posterior cerebral artery (PCA) watershed territory. Magnetic resonance angiography (MRA), Doppler ultrasonography, and digital subtraction angiography revealed severe right internal carotid artery (ICA) stenosis. The patient underwent carotid endarterectomy. The second patient was a 48-year-old male with acu...

  20. Simultaneous occurrence of a large asymptomatic prolapsing left atrial myxoma with a cutaneous squamous cell carcinoma.

    Science.gov (United States)

    Iltumur, Kenan; Demir, Tolga; Ariturk, Zuhal; Toprak, Nizamettin; Oto, Oztekin

    2015-02-27

    Synchronous myxoma of the heart and other malignancies are extremely rare. We report a case of a 64-year-old man who had a large left atrial myxoma that obstructed the mitral valve, as well as an unrelated, coexistent cutaneous squamous cell carcinoma in the sacral area. During the preoperative evaluation for non-cardiac surgery, the tumor was diagnosed coincidentally by echocardiographic examination. Echocardiography findings were consistent with a large left atrial myxoma originating from the posterior wall and prolapsing into the left ventricular cavity through the mitral valve, causing mitral stenosis. The mass was successfully completely excised. Histologic examination of the mass confirmed the diagnosis of cardiac myxoma. We report a casual echocardiographic finding of a left atrial myxoma that obstructed the mitral valve outflow tract, and an unrelated, synchronous cutaneous squamous cell carcinoma in the sacral area.

  1. The genus Hippocampus--a review on traditional medicinal uses, chemical constituents and pharmacological properties.

    Science.gov (United States)

    Chen, Lu; Wang, Xiaoyu; Huang, Baokang

    2015-03-13

    Several species from the genus Hippocampus have been widely used as a traditional medicine or invigorant with long history in China. Five species of them have been recorded in Chinese pharmacopoeia with name Hippocampus (Chinese name Haima [symbol: see text]). The ethnopharmacologial history of this genus indicated that they possess anti-tumor, anti-aging, anti-fatigue, anti-prostatic hyperplasia activities and can be used for the treatment of tumor, aging, fatigue, thrombus, inflammatory, hypertension and impotence. This review focuses on the traditional medicinal uses of Hippocampus species, as well as the phytochemical, pharmacological and toxicological studies on this genus. To provide an overview of the ethnopharmacology, chemical constituents, pharmacology and clinical applications of the genus Hippocampus, and to reveal their therapeutic potentials and being an evidence base for further research works of the Hippocampus. Information on the Hippocampus species was collected from scientific journals, books, thesis and reports based on the Chinese herbal classic literature and worldwide accepted scientific databases via a library and electronic search (PubMed, Elsevier, Scopus, Google Scholar, Springer, Web of Science and CNKI). A survey of literature revealed that the major chemical constituents of Hippocampus are sterides, essential amino acids, fatty acids and microelements. Experimental evidences confirmed that the Hippocampus could be used in treating tumor, aging, fatigue, thrombus, inflammatory, hypertension, prostatic hyperplasia and impotence. The most important function of Hippocampus in TCM is invigorating kidney-yang. The key traditional uses of Hippocampus have been investigated in vitro and in vivo, but their mechanism and clinical trial data are needed, and the sustainable exploitation of the endangered Hippocampus species should be considered. This literature analysis of traditional medicinal uses and experimental chemical and pharmacological

  2. Plain radiographic diagnosis of thrombosis of left atrial appendage in mitral valve disease

    International Nuclear Information System (INIS)

    Matsuyama, S.; Watabe, T.; Kuribayashi, S.

    1983-01-01

    Conventional posteroanterior chest radiographs of 42 patients with mitral valve disease who had had surgery were analyzed, and particular attention was directed to the presence or absence of the convexity of the left lower midcardiac border (left artrial segment). The flatness or concavity of this segment, despite other evidence of left atrial enlargement, was observed in six (60%) of 10 patients who had left atrial thrombosis, and in three (9%) of 32 patients who did not have thrombosis (false positive diagnosis). Four of the 10 patients who had left atrial thrombosis did not show this finding on the radiographs (false negative diagnosis). One of these four had a thrombus only against the posterior wall of the body of the left atrium. Therefore, the accuracy in the diagnosis of thrombosis of the left atrial appendage was 66.7% (six of nine) for patients who had thrombosis of the appendage. Standard chest radiographs are important in the evaluation of the patient with thrombosis of the left atrial appendage

  3. Serotonin in the ventral hippocampus modulates anxiety-like behavior during amphetamine withdrawal.

    Science.gov (United States)

    Tu, W; Cook, A; Scholl, J L; Mears, M; Watt, M J; Renner, K J; Forster, G L

    2014-12-05

    Withdrawal from amphetamine is associated with increased anxiety and sensitivity to stressors which are thought to contribute to relapse. Rats undergoing amphetamine withdrawal fail to exhibit stress-induced increases in serotonin (5-HT) release in the ventral hippocampus and show heightened anxiety-like behaviors. Therefore, we tested the hypothesis that reducing 5-HT levels in the ventral hippocampus is a causal mechanism in increasing anxiety-like behaviors during amphetamine withdrawal. First, we tested whether reducing 5-HT levels in the ventral hippocampus directly increases anxiety behavior. Male rats were bilaterally infused with 5,7-dihydroxytryptamine (5,7-DHT) into the ventral hippocampus, which produced a 83% decrease in ventral hippocampus 5-HT content, and were tested on the elevated plus maze (EPM) for anxiety-like behavior. Reducing ventral hippocampus 5-HT levels decreased the time spent in the open arms of the maze, suggesting that diminished ventral hippocampus 5-HT levels increases anxiety-like behavior. Next, we tested whether increasing 5-HT levels in the ventral hippocampus reverses anxiety behavior exhibited by rats undergoing amphetamine withdrawal. Rats were treated daily with either amphetamine (2.5-mg/kg, i.p.) or saline for 2weeks, and at 2weeks withdrawal, were infused with the selective serotonin reuptake inhibitor paroxetine (0.5μM) bilaterally into the ventral hippocampus and tested for anxiety-like behavior on the EPM. Rats pre-treated with amphetamine exhibited increased anxiety-like behavior on the EPM. This effect was reversed by ventral hippocampus infusion of paroxetine. Our results suggest that 5-HT levels in the ventral hippocampus are critical for regulating anxiety behavior. Increasing 5-HT levels during withdrawal may be an effective strategy for reducing anxiety-induced drug relapse. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

  4. Recruitment of Anterior and Posterior Structures in Lexical-Semantic Processing: An fMRI Study Comparing Implicit and Explicit Tasks

    Science.gov (United States)

    Ruff, Ilana; Blumstein, Sheila E.; Myers, Emily B.; Hutchison, Emmette

    2008-01-01

    Previous studies examining explicit semantic processing have consistently shown activation of the left inferior frontal gyrus (IFG). In contrast, implicit semantic processing tasks have shown activation in posterior areas including the superior temporal gyrus (STG) and the middle temporal gyrus (MTG) with less consistent activation in the IFG.…

  5. Temporización inmediata de implantes unitarios en la maxila posterior Immediate temporization of posterior maxilla single tooth implant

    Directory of Open Access Journals (Sweden)

    Y Leighton

    2011-04-01

    clinical study observed 21 partially edentulous subjects with lip scar and antagonistic natural teeth in the posterior maxilla for a period of 6 months in which conical threaded internal implant connections were inserted with a surface treatment and timed immediately after being inserted into the jawbone by producing an acrylic resin crown on a temporary titanium abutment screwed directly into the implant and left without tooth contacts during the Maximal Intercuspal (MIC and mandibular eccentric movements. All restorations were observed over a period of 6 months evaluating implant success rate and biological and mechanical complications. Results: 25 implants were inserted into 21 patients yielding an average surgical insertion torque of 45.6 Nt. During the clinical observation there was 100% success of implant survival. No biological complications were detected, but there were mechanical complications - a buccal cusp fracture of an acrylic provisional restoration and two screws loosening. Conclusions: The unit temporization by temporary screwing is a predictable and reliable protocol that allows osseointegration and the coexistence in the health of peri-implant tissue and its prosthetic system.

  6. MRI of the fetal posterior fossa

    Energy Technology Data Exchange (ETDEWEB)

    Adamsbaum, Catherine; Andre, Christine; Merzoug, Valerie; Ferey, Solene [St Vincent de Paul Hospital, Department of Radiology, Paris Cedex 14 (France); Moutard, Marie Laure [St Vincent de Paul Hospital, Department of Neuropaediatrics, Paris (France); Quere, Marie Pierre [CHU, Department of Radiology, Nantes (France); Lewin, Fanny [St Vincent de Paul Hospital, Maternity Department, Paris (France); Fallet-Bianco, Catherine [Ste Anne Hospital, Department of Neuropathology, Paris (France)

    2005-02-01

    MRI is a useful tool to complement US for imaging of the fetal posterior fossa (PF). In France, the discovery of a PF malformation in the fetus frequently leads to termination of pregnancy (80% in a personal series). However, despite improved accuracy in the diagnosis of PF abnormalities, prognosis remains uncertain. The first objective of this review is to document the normal MRI landmarks of the developing fetal PF. Because of their thinness, the visibility of the cerebellar fissures is dramatically delayed on MRI compared to macroscopic data. An important landmark is identification of the primary fissure of the vermis, normally seen at around 25-26 weeks' gestation (WG) on the sagittal slice, separating the larger posterior lobe from the anterior lobe (volume ratio around 2:1). The prepyramidal and secondary fissures are usually only identifiable after 32 WG and the hemispheric fissures are difficult to see until the end of pregnancy. Considering the signal changes, high signal on T2-weighted (T2-W) sequences is seen from 25 WG in the posterior part of the brain stem (tegmentum and ascending sensory tracts) related to myelination. The low signal intensities seen within the cerebellum on T2-W images correspond to high cellularity of grey matter (deep nuclei), as there is no myelination within the white matter before 38 WG. The second objective is to highlight the signs highly predictive of a poor neurological prognosis. Lack of pontine curvature or vermian agenesis without a PF cyst (small volume of PF) is greatly associated with poor neurological status. The third objective is to propose a diagnostic strategy in difficult cases where prognosis is important, e.g. the Dandy Walker continuum. (orig.)

  7. MRI of the fetal posterior fossa

    International Nuclear Information System (INIS)

    Adamsbaum, Catherine; Andre, Christine; Merzoug, Valerie; Ferey, Solene; Moutard, Marie Laure; Quere, Marie Pierre; Lewin, Fanny; Fallet-Bianco, Catherine

    2005-01-01

    MRI is a useful tool to complement US for imaging of the fetal posterior fossa (PF). In France, the discovery of a PF malformation in the fetus frequently leads to termination of pregnancy (80% in a personal series). However, despite improved accuracy in the diagnosis of PF abnormalities, prognosis remains uncertain. The first objective of this review is to document the normal MRI landmarks of the developing fetal PF. Because of their thinness, the visibility of the cerebellar fissures is dramatically delayed on MRI compared to macroscopic data. An important landmark is identification of the primary fissure of the vermis, normally seen at around 25-26 weeks' gestation (WG) on the sagittal slice, separating the larger posterior lobe from the anterior lobe (volume ratio around 2:1). The prepyramidal and secondary fissures are usually only identifiable after 32 WG and the hemispheric fissures are difficult to see until the end of pregnancy. Considering the signal changes, high signal on T2-weighted (T2-W) sequences is seen from 25 WG in the posterior part of the brain stem (tegmentum and ascending sensory tracts) related to myelination. The low signal intensities seen within the cerebellum on T2-W images correspond to high cellularity of grey matter (deep nuclei), as there is no myelination within the white matter before 38 WG. The second objective is to highlight the signs highly predictive of a poor neurological prognosis. Lack of pontine curvature or vermian agenesis without a PF cyst (small volume of PF) is greatly associated with poor neurological status. The third objective is to propose a diagnostic strategy in difficult cases where prognosis is important, e.g. the Dandy Walker continuum. (orig.)

  8. SINDROME DE COLAPSO DE MORDIDA POSTERIOR

    Directory of Open Access Journals (Sweden)

    Paula Alejandra Baldión

    2012-12-01

    Full Text Available El Síndrome de Colapso de Mordida posterior es una patología oclusal que se presenta como consecuencia de problemas dentales, periodontales y oclusales, que exige la correcta evaluación de los signos y síntomas que lo caracterizan.  El objetivo del artículo es describir la manera como evoluciona la enfermedad, la evaluación multidisciplinaria para obtener un diagnóstico preciso y la secuencia de tratamiento integral, revisando los conceptos para un mejor entendimiento del tratamiento periodontal y restaurativo que requieren los pacientes con síndrome de colapso de mordida posterior; caracterizado por procesos patológicos como enfermedad periodontal, caries dental con subsecuente alteración de la integridad del arco dentario que genera perdida de soporte posterior conllevando a un trauma oclusal secundario y disminución de la dimensión vertical oclusal. El control del proceso inflamatorio y la estabilización periodontal son puntos de partida indispensables en el tratamiento integral del paciente. La migración patológica de los dientes y las alteraciones del plano oclusal pueden exigir la corrección ortodóntica de los arcos y en algunos casos el concurso de cirugía oral para la nivelación del plano oclusal. La secuencia organizada del tratamiento por fases permite la restauración predecible de los pacientes con este síndrome, tomando en cuenta las diferentes alternativas protésicas tanto removibles como fijas con o sin implantes de oseointegración, para el éxito integral a largo plazo.

  9. Posterior surgery in high-grade spondylolisthesis.

    Science.gov (United States)

    Lengert, R; Charles, Y P; Walter, A; Schuller, S; Godet, J; Steib, J-P

    2014-09-01

    High-grade L5-S1 spondylolisthesis alters sagittal spinopelvic balance, which can cause low back pain and progressive neurologic disorder. The present study assessed spondylolisthesis reduction and maintenance over time with L4-S1 versus L5-S1 fusion using a lever-arm system and posterior fusion combined with lumbosacral graft. Forty patients were operated on for symptomatic high-grade spondylolisthesis, 34 of whom had full pre- and post-operative radiological analysis, with a mean follow-up of 5.4years. There were 9 L5-S1 and 25 L4-S1 instrumentations. Analysis of spinopelvic and slipping parameters and the evolution of segmental lordosis compared results between L5-S1 and L4-S1 instrumentation. Mean Taillard spondylolisthesis index decreased from 64% to 37% (P=0.0001). Overall sagittal spinopelvic balance was not significantly changed. Overall L1-S1 and segmental L4-L5 lordosis were not affected by instrumentation. Mean L5-S1 segmental lordosis increased from 11° to 18°. There was loss of reduction from 19° to 14° with L5-S1 instrumentation, in contrast to maintained reduction with L4-S1 instrumentation (P=0.006). The lever-arm system provided anterior-posterior reduction of spondylolisthesis and corrected slippage. Postoperative change in overall sagittal spinopelvic balance was slight and constant. Posterior L4-S1 fusion provided better long-term control of L5-S1 lordosis reduction than the shorter L5-S1 fusion. Retrospective study of level IV. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  10. Left Activism, Succour and Selfhood

    DEFF Research Database (Denmark)

    Hughes, Celia Penelope

    2014-01-01

    an interchange of motherhood, domesticity, far-left politics, and close female friendship. The article will show how the women's epistolary friendship offers intimate insight into female self-fashioning at a breakthrough social and political moment in 1970s Britain. As they reflected on some of the key political...

  11. Visualization of Fiber Structure in the Left and Right Ventricle of a Human Heart

    International Nuclear Information System (INIS)

    Rohmer, Damien; Sitek, Arkadiusz; Gullberg, Grant T.

    2006-01-01

    The human heart is composed of a helical network of muscle fibers. Anisotropic least squares filtering followed by fiber tracking techniques were applied to Diffusion Tensor Magnetic Resonance Imaging(DTMRI) data of the excised human heart. The fiber configuration was visualized by using thin tubes to increase 3-dimensional visual perception of the complex structure. All visualizations were performed using the high-quality ray-tracing software POV-Ray. The fibers are shown within the left and right ventricles. Both ventricles exhibit similar fiber architecture and some bundles of fibers are shown linking right and left ventricles on the posterior region of the heart

  12. The Posterior Fossa and Foreign Accent Syndrome: Report of Two New Cases and Review of the Literature.

    Science.gov (United States)

    Keulen, Stefanie; Mariën, Peter; van Dun, Kim; Bastiaanse, Roelien; Manto, Mario; Verhoeven, Jo

    2017-08-01

    Foreign accent syndrome is a rare motor speech disorder that causes patients to speak their language with a non-native accent. In the neurogenic condition, the disorder develops after lesions in the language dominant hemisphere, often affecting Broca's area, the insula, the supplementary motor area and the primary motor cortex. Here, we present two new cases of FAS after posterior fossa lesions. The first case is a 44-year-old, right-handed, Dutch-speaking man who suffered motor speech disturbances and a left hemiplegia after a pontine infarction. Quantified SPECT showed a bilateral hypoperfusion in the inferior lateral prefrontal and medial inferior frontal regions as well as a significant left cerebellar hypoperfusion. Further clinical investigations led to an additional diagnosis of brainstem cognitive affective syndrome which closely relates to Schmahmann's syndrome. The second patient was a 72-year-old right-handed polyglot English man who suffered a stroke in the vascular territory of the left posterior inferior cerebellar artery (PICA) and developed a foreign accent in his mother tongue (English) and in a later learnt language (Dutch). In this paper, we discuss how the occurrence of this peculiar motor speech disorder can be related to a lesion affecting the posterior fossa structures.

  13. Post-partum posterior reversible encephalopathy syndrome

    DEFF Research Database (Denmark)

    Aaen, Anne Albers; Jeppesen, Jørgen; Obaid, Hayder

    2015-01-01

    Posterior reversible encephalopathy syndrome (PRES) is a complex clinical condition with vasogenic subcortical oedema caused by hypertension. Oedema is often seen on magnetic resonance imaging. The wide clinical spectrum ranges from headaches to vision loss and even death. Early diagnosis...... and treatment is important for the reversibility of the condition. In this case report we emphasize the importance of blood pressure control in a post-partum woman, who had a rather complicated pregnancy. The symptoms of PRES were not recognized immediately because of failure to use and acknowledge a blood...

  14. Posterior breast cancer: Mammographic and ultrasonographic features

    Directory of Open Access Journals (Sweden)

    Janković Ana

    2013-01-01

    Full Text Available Background/Aim. Posterior breast cancers are located in the prepectoral region of the breast. Owing to this distinctive anatomical localization, physical examination and mammographic or ultrasonographic evaluation can be difficult. The purpose of the study was to assess possibilities of diagnostic mammography and breast ultrasonography in detection and differentiation of posterior breast cancers. Methods. The study included 40 women with palpable, histopathological confirmed posterior breast cancer. Mammographic and ultrasonographic features were defined according to Breast Imaging Reporting and Data System (BI-RADS lexicon. Results. Based on standard two-view mammography 87.5%, of the cases were classified as BI-RADS 4 and 5 categories, while after additional mammographic views all the cases were defined as BIRADS 4 and 5 categories. Among 96 mammographic descriptors, the most frequent were: spiculated mass (24.0%, architectural distortion (16.7%, clustered microcalcifications (12.6% and focal asymmetric density (12.6%. The differentiation of the spiculated mass was significantly associated with the possibility to visualize the lesion at two-view mammography (p = 0.009, without the association with lesion diameter (p = 0.083 or histopathological type (p = 0.055. Mammographic signs of invasive lobular carcinoma were significantly different from other histopathological types (architectural distortion, p = 0.003; focal asymmetric density, p = 0.019; association of four or five subtle signs of malignancy, p = 0.006. All cancers were detectable by ultrasonography. Mass lesions were found in 82.0% of the cases. Among 153 ultrasonographic descriptors, the most frequent were: irregular mass (15.7%, lobulated mass (7.2%, abnormal color Doppler signals (20.3%, posterior acoustic attenuation (18.3%. Ultrasonographic BI-RADS 4 and 5 categories were defined in 72.5% of the cases, without a significant difference among various histopathological types (p = 0

  15. A Short History of Posterior Dynamic Stabilization

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    Cengiz Gomleksiz

    2012-01-01

    Full Text Available Interspinous spacers were developed to treat local deformities such as degenerative spondylolisthesis. To treat patients with chronic instability, posterior pedicle fixation and rod-based dynamic stabilization systems were developed as alternatives to fusion surgeries. Dynamic stabilization is the future of spinal surgery, and in the near future, we will be able to see the development of new devices and surgical techniques to stabilize the spine. It is important to follow the development of these technologies and to gain experience using them. In this paper, we review the literature and discuss the dynamic systems, both past and present, used in the market to treat lumbar degeneration.

  16. Superior labrum anterior-to-posterior tear.

    Science.gov (United States)

    Sum, Jonathan C; Omid, Reza

    2012-12-01

    The patient was a 25-year-old male college student with a chief complaint of right shoulder pain. The patient was initially diagnosed with bicipital tendinitis by his physician and had been treated for 4 weeks by a physical therapist. However, his symptoms did not improve and he was unable to return to his preinjury activity levels, so he sought the services of another physical therapist for a second opinion. Due to concern for a labrum tear, the physical therapist referred the patient to an orthopaedic surgeon. Magnetic resonance arthrography revealed findings consistent with a superior labrum anterior-to-posterior tear.

  17. [Surface ECG characteristics of right and left atrial flutter].

    Science.gov (United States)

    Rostock, Thomas; Konrad, Torsten; Sonnenschein, Sebastian; Mollnau, Hanke; Ocete, Blanca Quesada; Bock, Karsten; Spittler, Raphael; Huber, Carola; Theis, Cathrin

    2015-09-01

    Atrial tachycardia in virtually all areas of both atria has become more important in the clinical management of patients with previous complex atrial fibrillation ablation. Accurate interpretation of surface electrocardiogram (ECG) characteristics is of paramount importance to localize the origin of atrial tachycardia, particularly for planning interventional treatment. This article highlights the ECG features of different types of right and left atrial tachycardia. Typical right atrial flutter through the cavotricuspid isthmus conducts septally in a cranial direction and demonstrates sawtooth-like flutter waves which start negative in II, III and aVF and then show a steep slope upwards to the isoelectric line. The flutter rate typically ranges between 240-250 beats/min. In contrast, right atrial flutter in a clockwise rotation, flutter around the vena cava inferior or superior and around a scar (e.g. after cardiac surgery) show positive or biphasic flutter waves (lower or upper loop reentry). Left atrial flutter waves (e.g. around the mitral valve or around the pulmonary veins) are very heterogeneous and are typically positive in V1 as the left atrium is located in the posterior mediastinum. Specific knowledge of flutter wave morphology in surface ECG facilitates planning and performance of the ablation strategy.

  18. Rare Case of Posterior Reversible Leukoencephalopathy Syndrome Secondary to Acute Chest Syndrome

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    Rohit Aiyer

    2016-01-01

    Full Text Available We present a case of 29/m with a history of sickle cell disease who presented to the emergency department with sudden onset of chest, trunk, extremity, and back pain, consistent in quality and severity with the patient’s usual pain crises. Soon after admission to the medical unit for acute chest syndrome (ACS, the patient developed sudden onset of hypertension associated with left sided hemiplegia, lethargy, dysarthria, aphasia, and left sided facial droop. Neuroimaging revealed that on MRI Brain there was multifocal extensive signal abnormality and a small focal areas of hemorrhage compatible with posterior reversible leukoencephalopathy syndrome (PRES. Patient was treated with levetiracetam and phenytoin and improved soon afterwards, with resolution seen on follow-up MRI two months later.

  19. [A 70-year-old woman presenting with restless shoulder following posterior internal capsule infarction].

    Science.gov (United States)

    Matsubara, Takeo; Suzuki, Keisuke; Okamura, Madoka; Shiina, Tomohiko; Miyamoto, Masayuki; Nakamura, Toshiki; Hirata, Koichi

    2017-11-25

    A 70-year-old woman noticed difficulty in speech and weakness of the left upper and lower limb upon awakening. Neurological examination showed dysarthria and left hemiparesis. No sensory disturbance was observed. Brain MRI revealed acute infarction in the right posterior limb of the internal capsule. On the hospital day 1, she developed the abnormal sensations restricted to the bilateral shoulders, resulting in difficulty initiating sleep. On laboratory data, renal function and serum hemoglobin and ferritin levels were normal. When four essential features of restless legs syndrome (RLS) were applied to her shoulders, the patient met RLS criteria. Following low dose pramipexole treatment, the abnormal sensation of the shoulders and insomnia significantly improved. We should be aware of the possibility of RLS or its variant, including "restless shoulder" of our patient, for the cause of insomnia following acute ischemic infarction.

  20. [Optimization of capsulotomy of enhanced posterior soft tissue repair in total hip arthroplasty].

    Science.gov (United States)

    Li, Qi; Zhang, Licheng; Yang, Guojing; Cai, Chunyuan; Tang, Chengxuan; Yu, Rutang; Yang, Xindong; Dong, Miuwu; Zhu, Hua

    2008-07-01

    To investigate the anatomic feature of the posterior hip joint capsule and its distributional difference of collagen fibers and to probe the optimization of the capsulotomy which can reserve the best strength part. Ten adult cadaver pelvises (6 males and 4 females, aged 28-64 years) fixed with formalin were used. Ten right hips were used for anatomical experiment of hip joint capsule. The posterior hip joint capsules were divided into 3 sectors (I-III sectors) and 9 parts (I(A-C), II(D-F), III(G-I). The average thickness of each part was measured and the ischiofemorale ligaments were observed. Five capsules selected from ten left hips were used for histological experiment. The content of collagen fibers in sector I and sector II was analyzed by Masson's staining. Two fresh frozen specimens which were voluntary contributions were contrasted with the fixed specimens. The optimal incision line of the posterior capsule was designed and used. The thickness in the posterior hip joint capsule [I(A) (2.30 +/- 0.40), I(B) (4.68 +/- 0.81), I(C) (2.83 +/- 0.69), II(D) (2.80 +/- 0.79), II(E) (4.22 +/- 1.33), II(F) (2.50 +/- 0.54), III(G) (1.57 +/- 0.40), III(H) (2.60 +/- 0.63), III(I) (1.31 +/- 0.28) mm] had no uniformity (P ligament trunk went through two thicker parts (I(B) and II(E)). The distribution of the collagen fibers in sector I and sector II(I(A) 20.34% +/- 5.14%, I(B) 48.79% +/- 12.67%, I(C) 19.87% +/- 5.21%, II(D) 17.57% +/- 3.56%, II(E) 46.76% +/- 11.47%, II(F) 28.65% +/- 15.79%) had no uniformity (P ligaments between the fresh frozen specimens and the fixed specimens. The optimal incision line C-A-B-D-E of the posterior capsule was designed and put into clinical application. The remaining capsular flap comprise the most of the ischiofemorale ligament trunk and the part of gluteus minimus. Although enhanced posterior soft tissue repair in total hip arthroplasty was investigated deeply and obtained great development, but the postoperative dislocation rate was not

  1. Axial oblique projections - volumetric studies into left ventricular cast specimens of man

    International Nuclear Information System (INIS)

    Duebel, H.P.; Tschapek, A.; Akademie der Wissenschaften der DDR, Berlin. Zentralinstitut fuer Molekularbiologie)

    1984-01-01

    Single-plane and biplane cineradiography was applied in various axial oblique projections to 15 cast specimens of the left ventricle. Their volumes were calculated by the area-length method. In these model studies, sufficiently accurate volume calculation proved to be practicable by sitting-up projection (SUP), hepatoclavicular representation (HCP), and long-axis representation with 40 0 angulation in the anterior-posterior plane (SLP 2 C 2 ). The latter representation gave the smallest deviations from true volume. (orig.)

  2. Left ventricular diastolic performance of left ventricular hypertrophy

    Energy Technology Data Exchange (ETDEWEB)

    Ikezono, Tohru; Ozaki, Masaharu; Yamagishi, Takashi; Shimizu, Tatsuro; Furutani, Yuji; Kusukawa, Reizo

    1987-02-01

    To study left ventricular diastolic performance in different forms of left ventricular hypertrophy, ECG gated cardiac blood pool scan was performed in 11 patients with hypertrophic nonobstructive cardiomyopathy (HCM) and in 19 patients with hypertension (HT), and left ventricular volume curve (LVVC) was analyzed and compared with those of 13 normal subjects (N). Ejection fraction (EF) and early filling volume ratio (the ratio of volume increment of 100 msec later than the zero point in the first derivative of LVVC to the end diastolic volume) (%EFV) were computed from LVVC. Peak ejection rate (PER) and peak filling rate (PFR) were obtained from the first derivative of LVVC. Peak ejection acceleration (PEA) and peak filling acceleration (PFA) were calculated from the second derivative of LVVC. EF, PER and PEA did not show any difference between these 3 groups. PFR was lower in HT (2.6 +- 0.5) compared with those in HCM (3.0 +- 0.5) (p < 0.05) and in N (3.4 +- 0.5) (p < 0.001), but the %EFV in HCM (4.9 +- 1.8) was lower than those in HT (6.9 +- 1.9) (p < 0.01) and in N (11.4 +- 1.4) (p < 0.001). Moreover, PFA in HCM (27.9 +- 7.2) was increased than those in HT (20.2 +- 5.4) (p < 0.01) with no differences between HCM and N (29.4 +- 8.1). Significant correlation was observed between PFR and PFA (Y = 0.06X + 1.4. r = 0.856. p < 0.001). These result indicate that, in HCM, reduced increase in early left ventricular volume is compensated by a greater filling acceleration. In contrast, there is no compensation by filling acceleration in HT.

  3. Fast and robust extraction of hippocampus from MR images for diagnostics of Alzheimer's disease

    DEFF Research Database (Denmark)

    Lötjönen, Jyrki; Wolz, Robin; Koikkalainen, Juha

    2011-01-01

    Assessment of temporal lobe atrophy from magnetic resonance images is a part of clinical guidelines for the diagnosis of prodromal Alzheimer's disease. As hippocampus is known to be among the first areas affected by the disease, fast and robust definition of hippocampus volume would be of great...

  4. Memory and the Hippocampus: A Synthesis from Findings with Rats, Monkeys, and Humans.

    Science.gov (United States)

    Squire, Larry R.

    1991-01-01

    The role of the hippocampus in memory function is discussed. Work with rats, monkeys, and humans largely agrees concerning its function and structure. The hippocampus is essential for a type of memory designated "declarative," the ability to remember that a visual object was presented in a particular context. (SLD)

  5. Temporal lobe surgery for intractable epilepsy in children: What to do with the hippocampus?

    Science.gov (United States)

    Benifla, Mony; Bennet-Back, Odeya; Shorer, Zamir; Noyman, Iris; Bar-Yosef, Rima; Ekstein, Dana

    2017-11-01

    Resection of the hippocampus can cause verbal memory decline, especially in the pediatric population. Thus, preservation of the hippocampus can be crucial for the quality of life of children with intractable temporal lobe epilepsy (TLE) who are candidates for epilepsy surgery. We investigated techniques that determine whether the hippocampus is part of the epileptogenic zone and the outcomes of pediatric surgery aimed to spare the hippocampus. We accessed data of children with normal hippocampus on MRI, who underwent surgery for medically refractory TLE. To identify epileptogenic areas, electrocorticography was performed in patients with space occupying lesions adjacent to the hippocampus, and long term invasive monitoring in patients with nonlesional TLE. Postoperative seizure control was classified according to Engel I-IV; Class I indicates seizure-free. Eleven females and 11 males met study inclusion criteria; the mean age at surgery was 11.3 years. Cortical and hippocampal electrocorticography was performed in 15 patients and long term invasive hippocampal monitoring in seven. The hippocampus was preserved in 16 patients (73%) while hippocampectomy was performed in 6 (27%). At the end of a mean follow-up of 3.5 years, 94% (15/16) of the patients who did not undergo hippocampectomy were classified as Engel I, compared to 50% (3/6) who underwent hippocampectomy. Sparing the hippocampus in temporal lobe epilepsy surgery is possible with excellent seizure outcome, while using the proper intraoperative technique. Copyright © 2017 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  6. Decreased left temporal lobe volume of panic patients measured by magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    R.R. Uchida

    2003-07-01

    Full Text Available Reported neuroimaging studies have shown functional and morphological changes of temporal lobe structures in panic patients, but only one used a volumetric method. The aim of the present study was to determine the volume of temporal lobe structures in patients with panic disorder, measured by magnetic resonance imaging. Eleven panic patients and eleven controls matched for age, sex, handedness, socioeconomic status and years of education participated in the study. The mean volume of the left temporal lobe of panic patients was 9% smaller than that of controls (t21 = 2.37, P = 0.028. In addition, there was a trend (P values between 0.05 and 0.10 to smaller volumes of the right temporal lobe (7%, t21 = 1.99, P = 0.06, right amygdala (8%, t21 = 1.83, P = 0.08, left amygdala (5%, t21 = 1.78, P = 0.09 and left hippocampus (9%, t21 = 1.93, P = 0.07 in panic patients compared to controls. There was a positive correlation between left hippocampal volume and duration of panic disorder (r = 0.67, P = 0.025, with recent cases showing more reduction than older cases. The present results show that panic patients have a decreased volume of the left temporal lobe and indicate the presence of volumetric abnormalities of temporal lobe structures.

  7. Decreased left temporal lobe volume of panic patients measured by magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, R.R.; Del-Ben, C.M.; Araujo, D.; Crippa, J.A.; Graeff, F.G. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Dept. de Neurologia e Psicologia Medica]. E-mail: fgraeff@keynet.com.br; Santos, A.C. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Dept. de Clinica Medica; Guimaraes, F.S. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Dept. de Farmacologia

    2003-07-01

    Reported neuroimaging studies have shown functional and morphological changes of temporal lobe structures in panic patients, but only one used a volumetric method. The aim of the present study was to determine the volume of temporal lobe structures in patients with panic disorder, measured by magnetic resonance imaging. Eleven panic patients and eleven controls matched for age, sex, handedness, socioeconomic status and years of education participated in the study. The mean volume of the left temporal lobe of panic patients was 9% smaller than that of controls (t{sub 21} = 2.37, P = 0.028). In addition, there was a trend (P values between 0.05 and 0.10) to smaller volumes of the right temporal lobe (7%, t{sub 21} = 1.99, P = 0.06), right amygdala (8%, t{sub 21} = 1.83, P = 0.08), left amygdala (5%, t{sub 21} = 1.78, P 0.09) and left hippocampus (9%, t{sub 21} = 1.93, P = 0.07) in panic patients compared to controls. There was a positive correlation between left hippocampal volume and duration of panic disorder (r = 0.67, P = 0.025), with recent cases showing more reduction than older cases. The present results show that panic patients have a decreased volume of the left temporal lobe and indicate the presence of volumetric abnormalities of temporal lobe structures. (author)

  8. Decreased left temporal lobe volume of panic patients measured by magnetic resonance imaging

    International Nuclear Information System (INIS)

    Uchida, R.R.; Del-Ben, C.M.; Araujo, D.; Crippa, J.A.; Graeff, F.G.; Santos, A.C.; Guimaraes, F.S.

    2003-01-01

    Reported neuroimaging studies have shown functional and morphological changes of temporal lobe structures in panic patients, but only one used a volumetric method. The aim of the present study was to determine the volume of temporal lobe structures in patients with panic disorder, measured by magnetic resonance imaging. Eleven panic patients and eleven controls matched for age, sex, handedness, socioeconomic status and years of education participated in the study. The mean volume of the left temporal lobe of panic patients was 9% smaller than that of controls (t 21 = 2.37, P = 0.028). In addition, there was a trend (P values between 0.05 and 0.10) to smaller volumes of the right temporal lobe (7%, t 21 = 1.99, P = 0.06), right amygdala (8%, t 21 = 1.83, P = 0.08), left amygdala (5%, t 21 = 1.78, P 0.09) and left hippocampus (9%, t 21 = 1.93, P = 0.07) in panic patients compared to controls. There was a positive correlation between left hippocampal volume and duration of panic disorder (r = 0.67, P = 0.025), with recent cases showing more reduction than older cases. The present results show that panic patients have a decreased volume of the left temporal lobe and indicate the presence of volumetric abnormalities of temporal lobe structures. (author)

  9. Posterior Interosseous Nerve Syndrome from Thermal Injury

    Directory of Open Access Journals (Sweden)

    Vijay A. Singh

    2014-01-01

    Full Text Available Background. Due to anatomical proximity to bone, the radial nerve is the most frequently injured major nerve of the upper extremity, frequently secondary to fractures (Li et al. (2013. We describe an incidence when a branch of the radial nerve is injured as a result of a thermal injury. Observation. Radial nerve injury can occur anywhere along the anatomical course with varied etiologies, but commonly related to trauma. The most frequent site is in the proximal forearm involving the posterior interosseous branch. However, problems can occur at the junction of the middle and proximal thirds of the humerus and wrist radially. When the radial nerve is injured by a burn, a new rehabilitation dynamic arises. Not only does one agonize about the return of nerve function but also fret about the skin grafts that replaced the devitalized tissue housing that compartment. Discussion. Although posterior interosseous nerve syndrome has been described in the context of many different etiologies, it has not previously been discussed in relation to burn injuries. In this case, not only did the patient’s rehabilitation involve aggressive therapy for return of sensation and function of the arm, but also prevention of contracture normally seen in replacement of full thickness burns.

  10. Reconstruction of Acetabular Posterior Wall Fractures

    Science.gov (United States)

    Ahn, Jae-Min; Hur, Jun-Oh; Lee, Jong-Seo; Cheon, Sang-Jin

    2011-01-01

    Background The results after acetabular fracture are primarily related to the quality of the articular reduction. We evaluated the results of internal fixation of posterior wall fractures with using three-step reconstruction. Methods Thirty-three patients (mean age at the time of injury, 47.9 years; 28 males and 5 females) were followed for a minimum of 2 years after surgery. The three-step reconstruction included 1) preservation of soft tissues and reduction of the marginally impacted osteochondral (articular) fragments using screws, 2) filling the impacted cancellous void with a bone graft, and 3) reinforcement with buttress-plating. Clinical evaluation was done according to the criteria of D'aubigne and Postel, while the radiological criteria were those of Matta. The associated injuries and complications were evaluated. Results The clinical results were excellent in 15 (45.5%) patients and they were good in 5 (15.2%), (i.e., satisfactory in 60.7%), while the radiologic results were excellent in 10 (30.3%) and good in 14 (42.4%) (satisfactory in 72.7%). Heterotopic ossification was common, but this did not require excision, even without prophylactic treatment with indomethacin. Deep infection was the worst complication and this was accompanied by a poor outcome. Conclusions This study confirms that three-step reconstruction facilitates accurate and firm reduction of displaced posterior wall fractures of the acetabulum. Therefore, we anticipate less long-term arthrosis in the patients treated this way. PMID:21629471

  11. Treatment of posterior wall fractures of acetabulum.

    Science.gov (United States)

    Qi, Xin; Liu, Jian-Guo; Gong, Yu-Bao; Yang, Chen; Li, Shu-Qiang; Feng, Wei

    2009-04-01

    To explore the treatment methods and outcome of posterior wall fractures of the acetabulum. The data of 31 patients (25 males and 6 females, aged 19-59 years, mean: 40.5 years) with posterior wall fractures of the acetabulum hospitalized in our department from 2002 to 2006 were analyzed retrospectively in this study. The types of fractures, number of fragments, combined dislocations, and sciatic nerve function were documented before admission. All the fractures were treated with open reduction and internal fixation. Based on the fracture type and site, either screws alone or reconstructive plates were used. The patients were immobilized for an average of 12 weeks before partial weight bearing was permitted. After follow-up for 12-70 months (43.6 months on average), modified Merle d'Aubigne score was adopted to evaluate the outcomes of the operations. The percentages of the excellent, good, fair and poor results were 48.4%, 41.9%, 6.5%, and 3.3%, respectively, with a good to excellent rate of 90.2%. Idiopathic sciatic nerve injury occurred in only one case. The sciatic nerve should be routinely exposed and protected during the surgery. The type of fixation should be based on the fracture type and site. Prolonged immobilization may be helpful in improving the final outcomes.

  12. Hydatidosis of the liver and posterior mediastinum.

    Science.gov (United States)

    Quail, Jacob F; Gramins, Daniel L; Dutton, William D

    2015-01-01

    Cystic echinococcus (CE) is an endemic zoonosis secondary to infection by the larval form of the cestode Echinococcus granulosus. An intermediate host, humans enter the organism's life cycle by exposure to infected canid feces. The liver is the most common location of CE while mediastinal hydatid cysts are rarely reported. We report a case of synchronous CE of the liver and posterior mediastinum treated sequentially using chemotherapy, percutaneous aspiration with injection of a scolicidal agent and re-aspiration (PAIR) and then staged minimally-invasive surgeries. Synchronous CE involving the liver and posterior mediastinum is rare. The treatment of hydatid liver and mediastinal disease is multimodal including chemotherapy, percutaneous and laparoscopic or open surgical interventions. One option for controlled puncture of hepatic and mediastinal CE includes PAIR followed by surgery. The sequential use of chemotherapy and PAIR followed by surgery provides another treatment strategy for management of CE. We believe this strategy may be used safely in locations without endemic CE, including most regions of the United States. Published by Elsevier Ltd.

  13. Bayesian posterior distributions without Markov chains.

    Science.gov (United States)

    Cole, Stephen R; Chu, Haitao; Greenland, Sander; Hamra, Ghassan; Richardson, David B

    2012-03-01

    Bayesian posterior parameter distributions are often simulated using Markov chain Monte Carlo (MCMC) methods. However, MCMC methods are not always necessary and do not help the uninitiated understand Bayesian inference. As a bridge to understanding Bayesian inference, the authors illustrate a transparent rejection sampling method. In example 1, they illustrate rejection sampling using 36 cases and 198 controls from a case-control study (1976-1983) assessing the relation between residential exposure to magnetic fields and the development of childhood cancer. Results from rejection sampling (odds ratio (OR) = 1.69, 95% posterior interval (PI): 0.57, 5.00) were similar to MCMC results (OR = 1.69, 95% PI: 0.58, 4.95) and approximations from data-augmentation priors (OR = 1.74, 95% PI: 0.60, 5.06). In example 2, the authors apply rejection sampling to a cohort study of 315 human immunodeficiency virus seroconverters (1984-1998) to assess the relation between viral load after infection and 5-year incidence of acquired immunodeficiency syndrome, adjusting for (continuous) age at seroconversion and race. In this more complex example, rejection sampling required a notably longer run time than MCMC sampling but remained feasible and again yielded similar results. The transparency of the proposed approach comes at a price of being less broadly applicable than MCMC.

  14. Bayesian Posterior Distributions Without Markov Chains

    Science.gov (United States)

    Cole, Stephen R.; Chu, Haitao; Greenland, Sander; Hamra, Ghassan; Richardson, David B.

    2012-01-01

    Bayesian posterior parameter distributions are often simulated using Markov chain Monte Carlo (MCMC) methods. However, MCMC methods are not always necessary and do not help the uninitiated understand Bayesian inference. As a bridge to understanding Bayesian inference, the authors illustrate a transparent rejection sampling method. In example 1, they illustrate rejection sampling using 36 cases and 198 controls from a case-control study (1976–1983) assessing the relation between residential exposure to magnetic fields and the development of childhood cancer. Results from rejection sampling (odds ratio (OR) = 1.69, 95% posterior interval (PI): 0.57, 5.00) were similar to MCMC results (OR = 1.69, 95% PI: 0.58, 4.95) and approximations from data-augmentation priors (OR = 1.74, 95% PI: 0.60, 5.06). In example 2, the authors apply rejection sampling to a cohort study of 315 human immunodeficiency virus seroconverters (1984–1998) to assess the relation between viral load after infection and 5-year incidence of acquired immunodeficiency syndrome, adjusting for (continuous) age at seroconversion and race. In this more complex example, rejection sampling required a notably longer run time than MCMC sampling but remained feasible and again yielded similar results. The transparency of the proposed approach comes at a price of being less broadly applicable than MCMC. PMID:22306565

  15. Study of hemostasis procedures for posterior epistaxis.

    Science.gov (United States)

    Iimura, Jiro; Hatano, Atsushi; Ando, Yuji; Arai, Chiaki; Arai, Satoshi; Shigeta, Yasushi; Kojima, Hiromi; Otori, Nobuyoshi; Wada, Kota

    2016-06-01

    Hemostasis is difficult in patients with bleeding emanating from the deep regions in the nasal cavity; however, there is no standard treatment method. We studied hemostasis procedures in patients who visited our outpatient department and presented with idiopathic epistaxis extending from the posterior nasal cavity to Kiesselbach's area. The subjects were patients with epistaxis who visited our hospital between June 2008 and May 2010. We asked specific questions at the time of the hospital visit and examined patients using a nasal speculum, a flexible endoscope, and a rigid endoscope (0 or 70 degree) to identify bleeding sites. Hemostasis using electrocoagulation was selected as the first-line therapy for patients in whom a bleeding point had been identified, whereas hemostasis using a gauze tampon was performed in patients in whom the bleeding point was unknown. The subjects were analyzed by multivariate logistic regression analysis. The bleeding point was unknown in most cases of recurrent posterior epistaxis. Electrocoagulation was the best hemostasis procedure. Identifying the bleeding points as much as possible and performing electrocoagulation at these sites was the preferred procedures. We propose the treatment procedure for refractory epistaxis. When it is difficult to identify a bleeding point in a patient with refractory epistaxis due to a deviated nasal septum, a bleeding point should be identified after septoplasty; for bleeding from the sphenopalatine artery region, electrocoagulation or endoscopic cauterization of the sphenopalatine artery should be performed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  16. Incidence of intraoperative complications in cataract surgery performed by left-handed residents.

    Science.gov (United States)

    Kim, Jae Yong; Ali, Rasha; Cremers, Sandra Lora; Yun, Sung-Cheol; Henderson, Bonnie An

    2009-06-01

    To compare the incidence of intraoperative complications during cataract surgery performed by left-handed and right-handed residents and to find predictor variables for complications in resident-performed surgery. Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA. This retrospective chart review comprised cataract extractions performed by postgraduate fourth-year residents from July 1, 2001, to June 30, 2006. The incidence of posterior capsule tear and vitreous loss were the main outcomes. Univariate and multivariate logistic analyses incorporated the variables of patient age and sex; laterality of surgical eye; presence of diabetes mellitus, glaucoma, or age-related macular degeneration; history of vitrectomy; axial length; pseudoexfoliation; small pupils; white cataract; posterior polar cataract; handedness of resident; and academic quarter during which surgery occurred. Left-handed residents performed 170 (9.8%) of the 1730 surgeries. The incidence of posterior capsule tear and vitreous loss was significantly lower in surgeries performed by left-handed residents than in those performed by right-handed residents (P = .03 and Pleft-handed residents. Handedness and patient age were significant predictor variables for these complications.

  17. DTI and MR Volumetry of Hippocampus-PC/PCC Circuit: In Search of Early Micro- and Macrostructural Signs of Alzheimers's Disease.

    Science.gov (United States)

    Palesi, F; Vitali, P; Chiarati, P; Castellazzi, G; Caverzasi, E; Pichiecchio, A; Colli-Tibaldi, E; D'Amore, F; D'Errico, I; Sinforiani, E; Bastianello, S

    2012-01-01

    Hippocampal damage, by DTI or MR volumetry, and PET hypoperfusion of precuneus/posterior cingulate cortex (PC/PCC) were proposed as biomarkers of conversion from preclinical (MCI) to clinical stage of Alzheimer's disease (AD). This study evaluated structural damage, by DTI and MR volumetry, of hippocampi and tracts connecting hippocampus to PC/PCC (hipp-PC/PCC) in 10 AD, 10 MCI, and 18 healthy controls (CTRL). Normalized volumes, mean diffusivity (MD), and fractional anisotropy (FA) were obtained for grey matter (GM), white matter (WM), hippocampi, PC/PCC, and hipp-PC/PCC tracts. In hippocampi and hipp-PC/PCC tracts, decreased volumes and increased MD were found in AD versus CTRL (P PCC tract MD, and in MCI with FA of total WM. Both DTI and MR volumetry of hippocampi and hipp-PC/PCC tracts detect early signs of AD in MCI patients.

  18. Supramammillary afferents to guinea pig hippocampus contain substance P-like immunoreactivity.

    Science.gov (United States)

    Gall, C; Selawski, L

    1984-10-12

    The origin of substance P immunoreactive (SPI) axons in guinea pig hippocampus was analyzed using immunocytochemical techniques combined with transections and retrograde transport of fluorescent dye. A unilateral depletion of hippocampal axonal SPI was observed following ipsilateral transection of rostral hippocampus and fibria suggesting that the vast majority of SPI axons in hippocampus are extrinsic afferents which enter the structure from the septal pole. The combined use of immunocytochemistry and fluorescent dye transport demonstrated the supramammillary region of the hypothalamus to be the only area where dye-labeled hippocampal afferent neurons also exhibited SPI. These data indicate that the supramammillary region is the principal source of SPI axons in guinea pig hippocampus and, most probably, in the hippocampus of other animals (squirrel, cat, monkey) sharing a similar pattern of axonal SPI.

  19. Transient phonemic paraphasia by bilateral hippocampus lesion in a case of limbic encephalitis

    Directory of Open Access Journals (Sweden)

    Masahiko Kishi

    2010-03-01

    Full Text Available Although the hippocampus has not typically been identified as part of the language and aphasia circuit, recent evidence suggests that the hippocampus is closely related to naming, word priming, and anomic aphasia. A 59-year old woman with limbic encephalitis of possible autoimmune etiology, after recovery of consciousness, presented with severe memory impairment in both anterograde and retrograde modalities, episodes of fear, hallucination and convulsion, and transient fluent, phonemic paraphasia, together with small sharp waves diffusely by EEG. Brain MRI revealed bilateral symmetric, discrete lesions in the body to the infundibulum of the hippocampus. The transient phonemic paraphasia noted in our patient may have been a result of primary damage in the hippocampus and its fiber connection to the Wernicke’s area or secondary partial status epilepticus that might have originated in the hippocampus.

  20. Remembering and imagining differentially engage the hippocampus: a multivariate fMRI investigation.

    Science.gov (United States)

    Kirwan, C Brock; Ashby, Stefania R; Nash, Michelle I

    2014-01-01

    It has been proposed that imagining the future depends on the ability to retrieve episodic details from past experiences in order to recombine them into novel possible experiences; consequently, the processes of remembering and imagining rely on similar neural substrates, including the hippocampus. We used fMRI and both univariate and multivariate analysis techniques to test this prediction. Unbiased univariate analysis did not reveal differences in the hippocampus between remembering and imagining; however, multivariate analyses revealed evidence that patterns of activity within the hippocampus distinguish between remembering and imagining. Thus, while the hippocampus seems to be involved in both remembering the past and imagining the future, the pattern of activity within the hippocampus distinguishes between these two different tasks.

  1. The posterior medial cortex is involved in visual but not in verbal memory encoding processing: an intracerebral recording study.

    Science.gov (United States)

    Stillová, K; Jurák, P; Chládek, J; Halámek, J; Telecká, S; Rektor, I

    2013-03-01

    The objective is to study the involvement of the posterior medial cortex (PMC) in encoding and retrieval by visual and auditory memory processing. Intracerebral recordings were studied in two epilepsy-surgery candidates with depth electrodes implanted in the retrosplenial cingulate, precuneus, cuneus, lingual gyrus and hippocampus. We recorded the event-related potentials (ERP) evoked by visual and auditory memory encoding-retrieval tasks. In the hippocampus, ERP were elicited in the encoding and retrieval phases in the two modalities. In the PMC, ERP were recorded in both the encoding and the retrieval visual tasks; in the auditory modality, they were recorded in the retrieval task, but not in the encoding task. In conclusion, the PMC is modality dependent in memory processing. ERP is elicited by memory retrieval, but it is not elicited by auditory encoding memory processing in the PMC. The PMC appears to be involved not only in higher-order top-down cognitive activities but also in more basic, rather than bottom-up activities.

  2. An acute posterior myocardial infarction complicated with late pseudoaneurysm of the posterior wall.

    Science.gov (United States)

    Dewilde, Willem; Muyldermans, Luc; Delanote, Joost; Bol, Alexander

    2006-08-10

    Diagnostic image: An 80-year-old man is referred because of an acute posterior infarction. Because of persisting pain and apparition of a new murmur, an echocardiography is performed showing inferoposterolateral akinesis complicated by ventricular wall pseudoaneurysm. After discussing with patient and family, conservative therapy was continued. A clue for diagnosis of pseudoaneurysm is the presence of a systolic murmur.

  3. Adult Onset-hypothyroidism has Minimal Effects on Synaptic Transmission in the Hippocampus of Rats Independent of Hypothermia

    Science.gov (United States)

    Introduction: Thyroid hormones (TH) influence central nervous system (CNS) function during development and in adulthood. The hippocampus, a brain area critical for learning and memory is sensitive to TH insufficiency. Synaptic transmission in the hippocampus is impaired following...

  4. [The effect of Solcoseryl on explant cultures of the hippocampus].

    Science.gov (United States)

    Lindner, G; Grosse, G; Goworek, K; Franz, C; Liebezeit, K

    1979-01-01

    Explants of hippocampus from fetal rats were cultivated in Maximow chambers in semisynthetic medium up to 12 days in vitro. The cultures were fixed Bouin, slided 15 micron, coloured with Klüver-Barrera and some morphological parameters were tested. 1. The nerve fiber index increased by influence of 1% Solcoseryl in relation to control cultures, which growed in minimal medium. An essential stimulation was observed by application of placentar serum and embryonal extract into the culture medium. 2. Die decrease of the number of neurons and glial cells per unit of area and a small decrease of the area of neuron nuclei was discussed in relation to the effect of the pharmacon Solcoseryl on O2- consumption. 3. Solcoseryl (firm Solco AG, Base) is an extract of calf blood. It can not substitute other tissue extracts.

  5. Does posterior cingulate hypometabolism result from disconnection or local pathology across preclinical and clinical stages of Alzheimer's disease?

    Energy Technology Data Exchange (ETDEWEB)

    Teipel, Stefan [University of Rostock, Department of Psychosomatic Medicine, Rostock (Germany); DZNE, German Center for Neurodegenerative Diseases, Rostock (Germany); Alzheimer' s Disease Neuroimaging Initiative (United States); Grothe, Michel J. [DZNE, German Center for Neurodegenerative Diseases, Rostock (Germany); Alzheimer' s Disease Neuroimaging Initiative (United States)

    2016-03-15

    Posterior cingulate cortex (PCC) hypometabolism as measured by FDG PET is an indicator of Alzheimer's disease (AD) in prodromal stages, such as in mild cognitive impairment (MCI), and has been found to be closely associated with hippocampus atrophy in AD dementia.We studied the effects of local and remote atrophy and of local amyloid load on the PCC metabolic signal in patients with different preclinical and clinical stages of AD. We determined the volume of the hippocampus and PCC grey matter based on volumetric MRI scans, PCC amyloid load based on AV45 PET, and PCC metabolism based on FDG PET in 667 subjects participating in the Alzheimer's Disease Neuroimaging Initiative spanning the range from cognitively normal ageing through prodromal AD to AD dementia. In cognitively normal individuals and those with early MCI, PCC hypometabolism was exclusively associated with hippocampus atrophy, whereas in subjects with late MCI it was associated with both local and remote effects of atrophy as well as local amyloid load. In subjects with AD dementia, PCC hypometabolism was exclusively related to local atrophy. Our findings suggest that the effects of remote pathology on PCC hypometabolism decrease and the effects of local pathology increase from preclinical to clinical stages of AD, consistent with a progressive disconnection of the PCC from downstream cortical and subcortical brain regions. (orig.)

  6. Does posterior cingulate hypometabolism result from disconnection or local pathology across preclinical and clinical stages of Alzheimer's disease?

    International Nuclear Information System (INIS)

    Teipel, Stefan; Grothe, Michel J.

    2016-01-01

    Posterior cingulate cortex (PCC) hypometabolism as measured by FDG PET is an indicator of Alzheimer's disease (AD) in prodromal stages, such as in mild cognitive impairment (MCI), and has been found to be closely associated with hippocampus atrophy in AD dementia.We studied the effects of local and remote atrophy and of local amyloid load on the PCC metabolic signal in patients with different preclinical and clinical stages of AD. We determined the volume of the hippocampus and PCC grey matter based on volumetric MRI scans, PCC amyloid load based on AV45 PET, and PCC metabolism based on FDG PET in 667 subjects participating in the Alzheimer's Disease Neuroimaging Initiative spanning the range from cognitively normal ageing through prodromal AD to AD dementia. In cognitively normal individuals and those with early MCI, PCC hypometabolism was exclusively associated with hippocampus atrophy, whereas in subjects with late MCI it was associated with both local and remote effects of atrophy as well as local amyloid load. In subjects with AD dementia, PCC hypometabolism was exclusively related to local atrophy. Our findings suggest that the effects of remote pathology on PCC hypometabolism decrease and the effects of local pathology increase from preclinical to clinical stages of AD, consistent with a progressive disconnection of the PCC from downstream cortical and subcortical brain regions. (orig.)

  7. Effect of the N-methyl-D-aspartate NR2B subunit antagonist ifenprodil on precursor cell proliferation in the hippocampus.

    Science.gov (United States)

    Bunk, E C; König, H-G; Prehn, J H M; Kirby, B P

    2014-06-01

    The N-methyl-D-aspartate (NMDA) receptor, one of the ionotropic glutamate receptor, plays important physiological and pathological roles in learning and memory, neuronal development, acute and chronic neurological diseases, and neurogenesis. This work examines the contribution of the NR2B NMDA receptor subunit to adult neurogenesis/cell proliferation under physiological conditions and following an excitotoxic insult. We have previously shown in vitro that a discrete NMDA-induced, excitotoxic injury to the hippocampus results in an increase in neurogenesis within the dentate gyrus. Here we have characterized adult neurogenesis or proliferation, using BrdU, in an in vivo model of excitotoxic injury to the CA1 subfield of the hippocampus. We demonstrate a peak in neural stem cell proliferation/neurogenesis between 6 and 9 days after the excitotoxic insult. Treatment with ifenprodil, an NR2B subunit-specific NMDA receptor antagonist, without prior injury induction, also increased the number of BrdU-positive cells within the DG and posterior periventricle, indicating that ifenprodil itself could modulate the rate of proliferation. Interestingly, though, the increased level of cell proliferation did not change significantly when ifenprodil was administered following an excitotoxic insult. In conclusion, our results suggest and add to the growing evidence that NR2B subunit-containing NMDA receptors play a role in neural stem cell proliferation. Copyright © 2014 Wiley Periodicals, Inc.

  8. Producing The New Regressive Left

    DEFF Research Database (Denmark)

    Crone, Christine

    This thesis is the first comprehensive research work conducted on the Beirut based TV station, an important representative of the post-2011 generation of Arab satellite news media. The launch of al-Mayadeen in June 2012 was closely linked to the political developments across the Arab world...... members, this thesis investigates a growing political trend and ideological discourse in the Arab world that I have called The New Regressive Left. On the premise that a media outlet can function as a forum for ideology production, the thesis argues that an analysis of this material can help to trace...... the contexture of The New Regressive Left. If the first part of the thesis lays out the theoretical approach and draws the contextual framework, through an exploration of the surrounding Arab media-and ideoscapes, the second part is an analytical investigation of the discourse that permeates the programmes aired...

  9. Coding of Event Nodes and Narrative Context in the Hippocampus.

    Science.gov (United States)

    Milivojevic, Branka; Varadinov, Meryl; Vicente Grabovetsky, Alejandro; Collin, Silvy H P; Doeller, Christian F

    2016-12-07

    Narratives may provide a general context, unrestricted by space and time, which can be used to organize episodic memories into networks of related events. However, it is not clear how narrative contexts are represented in the brain. Here we test the novel hypothesis that the formation of narrative-based contextual representations in humans relies on the same hippocampal mechanisms that enable formation of spatiotemporal contexts in rodents. Participants watched a movie consisting of two interleaved narratives while we monitored their brain activity using fMRI. We used representational similarity analysis, a type of multivariate pattern analysis, which uses across-voxel correlations as a proxy for neural-pattern similarity, to examine whether the patterns of neural activity can be used to differentiate between narratives and recurring narrative elements, such as people and locations. We demonstrate that the neural activity patterns in the hippocampus differentiate between event nodes (people and locations) and narratives (different stories) and that these narrative-context representations diverge gradually over time akin to remapping-induced spatial maps represented by rodent place cells. Narratives, especially in movie format, are very engaging and can be used to investigate neural mechanisms underlying cognitive functions in more naturalistic settings than that of traditional paradigms. Narratives also provide a more general context, unrestricted by space and time, that can be used to organize memories into networks of related events. For this reason, narratives are ideally suited to engage neural mechanisms underlying episodic memory formation. In this study, participants watched a movie with two interleaved narratives while their brain activity was monitored using fMRI. We show that the hippocampus, which is involved in formation of spatiotemporal contexts in episodic memory, also represents gradually diverging narrative contexts as well as narrative elements

  10. Comparison of Glenoid Version and Posterior Humeral Subluxation in Patients With and Without Posterior Shoulder Instability.

    Science.gov (United States)

    Parada, Stephen A; Eichinger, Josef K; Dumont, Guillaume D; Burton, Lauren E; Coats-Thomas, Maggie S; Daniels, Stephen D; Sinz, Nathan J; Provencher, Matthew T; Higgins, Laurence D; Warner, Jon J P

    2017-02-01

    To evaluate glenoid version and humeral subluxation on preoperative multiplanar imaging of patients who underwent surgery for posterior glenohumeral instability compared with a matched group of patients who had shoulder surgery for other pathology. All patients over a 2-year period who underwent surgery for posterior instability had preoperative magnetic resonance (MR) imaging or MR arthrogram reviewed. Patients undergoing shoulder surgery for reasons other than instability were identified as a control group and matched by sex, laterality, and age. Measurement of glenoid version and percentage of humeral subluxation was performed by 2 reviewers after completing a tutorial. Reviewers were blinded to diagnosis and to whether or not the patients were in the experimental or control group. There were 41 patients in each group. The average glenoid version in the control group was 5.6° of retroversion (standard deviation [SD] 3.0), and the average humeral subluxation was 54% (SD 5.1%). In the experimental group, the average glenoid version was 8.1° of retroversion (SD 5.0). The average humeral subluxation in the experimental group was 56% (SD 6.8%). Student t test revealed a statistically significant difference in glenoid version (P = .009) but not humeral subluxation (P = .25). Intra- and inter-rater reliability was measured by the intraclass correlation coefficient and found to have an excellent Fleiss rating with regard to both measurements. Glenoid retroversion is significantly increased in patients with symptomatic posterior labral tears compared with a control group. However, there was no statistically significant difference between the groups with regard to posterior humeral subluxation and, therefore, is not a reliable indicator of the presence or absence of symptomatic posterior shoulder instability. Level III, retrospective comparative study. Published by Elsevier Inc.

  11. Tomographic evaluation on bone morphology in posterior mandibular region for safe placement of dental implant.

    Science.gov (United States)

    Yildiz, Selda; Bayar, Gurkan Rasit; Guvenc, Inanc; Kocabiyik, Necdet; Cömert, Ayhan; Yazar, Fatih

    2015-03-01

    The aim of this study was to examine the morphology of submandibular fossae at edentulous posterior regions of dried mandibles and to determine a safe range for proper lingual angulation during the placement of a dental implant in the posterior mandibular region, with a computerized tomographic scan study. Spiral computed tomographic images of 77 dry adult human mandibles were evaluated to determine the deepest area in the submandibular fossa. Then, the proper lingual angulations for the placement of a dental implant at these regions were measured. Pearson's correlation coefficient was calculated to show the relation between the depths of submandibular fossa and lingual implant angulations. "Paired t test" was used for differences between the lingual implant angulations and the depths of submandibular fossa on each side of the mandibles. Depths of the submandibular fossa and lingual implant angulations were varied between 1.1 and 4.6 mm: 62°-84° on right side of the mandibles, and 1.1-4.5 mm, 65°-83° on left side of the mandibles. There were statistically medium negative correlations between the degree of lingual implant angulations and the depth of submandibular fossa on each side of the mandible (r = -0.44, p dental implant placement in posterior mandible to avoid potential risk of lingual cortical plate perforation.

  12. [Biometric and biomechanic analysis of lumbar posterior facets based on a CT-scan database].

    Science.gov (United States)

    Bronsard, N; Serre, T; Staccini, P; Hovorka, I; Thollon, L; Padovani, B; de Peretti, F; Signoli, M; Tropiano, P

    2013-03-01

    Our knowledge on anatomy of lumbar spine is based on few cadaver's study with old and few subjects. CT-scan is very precise for lumbar facet's morphology. We have analysed 400 subjects. The aim of this study is to measure different distances, angles and circles to better understand the mechanical function of the lumbar facets. We have analysed 720 CT-scan. We had 217 men and 183 women with 59 years of mean age. We used native slices of 1.25 mm thick from L1 to S1. We created transversal plan and we put different mark point. We took their coordinates and we have calculated different distances, angles and mechanical circles. We have compared different axis of rotation of the facets. From L1 to S1, the facets goes near to the posterior wall and far from themselves. Moreover, the posterior angle between both facets increase down to the sacrum. The radius of the left side circle and the right one are very closed in 50% of the cases but the three radius are close only in 10% of cases. This study based on 400 subjects shows that there is not a unique axis of rotation for both lumbar posterior facets. We have had only 50% of symmetry between both sides whatever the level studied. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  13. [Application of xenograft for alveolar ridge preservation in posterior sites: a randomized controlled clinical trial].

    Science.gov (United States)

    Lei, Chi; Wu, Hui; Lin, Ye; Di, Ping; Chen, Bo; Hu, Xiulian

    2015-09-01

    To investigate the effect of ridge preservation with Bio-Oss Collagen and Bio-Gide in posterior sites. From May 2010 to July 2013, 16 patients with bilateral posterior teeth planned to be extracted and replaced by implants were enrolled. One of the sockets was randomly selected and presserved with Bio-Oss Collagen and Bio-Gide (intervention group). The contralateral socket was left to heal spontaneously (control group). Cone-beam (CBCT) scans were performed immediately after the extraction and 6 month later. The bone cores were collected during the implant placement surgery and analyzed by micro-computed tomography. After 6 month healing, the vertical and horizontal dimensional alteration of the treatment group were (0.55 ± 1.05) mm and (-0.99 ± 0.94) mm respectively, while the vertical and horizontal change of control group were (-0.71 ± 1.41) mm and (-2.26 ± 1.29) mm respectively. The micro-computed tomography results showed that there was no significant difference in new bone volume between control and intervention groups. Applying Bio-Oss Collagen and Bio-Gide for ridge preservation in posterior sites resulted in less vertical and horizontal bone resorption of sockets following extraction.

  14. Anatomical relationships between Wrisberg meniscofemoral and posterior cruciate ligament's femoral insertions

    Directory of Open Access Journals (Sweden)

    Heetor Campora de Sousa Oliveira

    2013-09-01

    Full Text Available OBJECTIVE: To evaluate the frequency and morphometry of the Wrisberg's ligament and its relationships with the posterior cruciate ligament's femoral insertion. STUDY DESIGN: Controlled laboratory study. METHODS: 24 unpaired knee pieces, 12 right and 12 left were submitted to a deep dissection of the Wrisberg and posterior cruciate ligaments. The pieces were photographed with a digital camera and ruler; the Image J software was used to measure the ligaments' insertion areas, in square millimeters. RESULTS: The Wrisberg ligament was present in 91.6% of the studied pieces. In those its shape was elliptical in 12 pieces (54.54%. In 68% of the knees, the WL insertion was proximal to the medial intercondilar ridge, close to the PCL posteromedial bundle. The average area for the WL was 20.46 ± 6.12 mm2. This number corresponded to 23.3% of the PCL's average area. CONCLUSIONS: WL ligament is a common structure in knees. There is a wide variation of its insertion area. Proportionally to the PCL's insertion area the WL ones suggests that it may contribute to the posterior stability of the knee joint.

  15. Objective assessment of mastication predominance in healthy dentate subjects and patients with unilateral posterior missing teeth.

    Science.gov (United States)

    Yamasaki, Y; Kuwatsuru, R; Tsukiyama, Y; Oki, K; Koyano, K

    2016-08-01

    We aimed to investigate mastication predominance in healthy dentate individuals and patients with unilateral posterior missing teeth using objective and subjective methods. The sample comprised 50 healthy dentate individuals (healthy dentate group) and 30 patients with unilateral posterior missing teeth (partially edentulous group). Subjects were asked to freely chew three kinds of test foods (peanuts, beef jerky and chewing gum). Electromyographic activity of the bilateral masseter muscles was recorded. The chewing side (right side or left side) was judged by the level of root mean square electromyographic amplitude. Mastication predominance was then objectively assessed using the mastication predominant score and the mastication predominant index. Self-awareness of mastication predominance was evaluated using a modified visual analogue scale. Mastication predominance scores of the healthy dentate and partially edentulous groups for each test food were analysed. There was a significant difference in the distribution of the mastication predominant index between the two groups (P < 0·05). The mastication predominant score was weakly correlated with self-awareness of mastication predominance in the healthy dentate group, whereas strong correlation was observed in the partially edentulous group (P < 0·05). The results suggest that the individuals with missing unilateral posterior teeth exhibited greater mastication predominance and were more aware of mastication predominance than healthy dentate individuals. Our findings suggest that an objective evaluation of mastication predominance is more precise than a subjective method. © 2016 John Wiley & Sons Ltd.

  16. Seeing is not feeling: posterior parietal but not somatosensory cortex engagement during touch observation.

    Science.gov (United States)

    Chan, Annie W-Y; Baker, Chris I

    2015-01-28

    Observing touch has been reported to elicit activation in human primary and secondary somatosensory cortices and is suggested to underlie our ability to interpret other's behavior and potentially empathy. However, despite these reports, there are a large number of inconsistencies in terms of the precise topography of activation, the extent of hemispheric lateralization, and what aspects of the stimulus are necessary to drive responses. To address these issues, we investigated the localization and functional properties of regions responsive to observed touch in a large group of participants (n = 40). Surprisingly, even with a lenient contrast of hand brushing versus brushing alone, we did not find any selective activation for observed touch in the hand regions of somatosensory cortex but rather in superior and inferior portions of neighboring posterior parietal cortex, predominantly in the left hemisphere. These regions in the posterior parietal cortex required the presence of both brush and hand to elicit strong responses and showed some selectivity for the form of the object or agent of touch. Furthermore, the inferior parietal region showed nonspecific tactile and motor responses, suggesting some similarity to area PFG in the monkey. Collectively, our findings challenge the automatic engagement of somatosensory cortex when observing touch, suggest mislocalization in previous studies, and instead highlight the role of posterior parietal cortex. Copyright © 2015 the authors 0270-6474/15/351468-13$15.00/0.

  17. [Judet posterior approach to the scapula].

    Science.gov (United States)

    Bartonícek, J; Tucek, M; Lunácek, L

    2008-12-01

    A detailed description of the Judet posterior approach to the scapula. The authors used this approach in 24 patients operated on for fractures of the scapular body and neck and for combined fractures of the scapula. In 23 patients the surgical site healed without complications, in 1 case revision was required due to a haematoma. DESCRIPTION OF THE APPROACH: The approach has three phases. The first of them consists in a boomerang skin incision along the scapular spine and the medial scapular border producing a skin flap, and identification of the posterior border of the deltoid. In the next phase, the posterior deltoid is dissected off the scapular spine and reflected laterally. In the final phase, the infraspinatus is mobilized and reflected proximally. During the whole procedure the neurovascular bundle passing from the spinoglenoid notch to the infraspinatus must be handled with maximum caution. In certain types of fractures of the scapula, this approach may be limited using a medial and a lateral window to expose the respective borders of the scapular body, without full mobilization of the infraspinatus. On the other hand, where the fracture of the scapula is associated with a fracture of the lateral clavicle or dislocation of the AC joint, the approach may be extended using a saber cut incision starting from the proximolateral angle of the Judet incision and passing over the AC joint. This modification was used in a fracture of the scapular body associated with dislocation of the AC joint. The advantage of the Judet approach is an excellent exposure of the infraspinousus fossa. The main disadvantage of this approach is considered its extensiveness and atrophy of the infraspinatus that is most probably caused by its mobilization. However, there may be more causes of this atrophy. The first of them is injury to the suprascapular nerve in fractures of the surgical neck of the scapula by its entrapment in the fracture line. In these fractures the whole course of

  18. Connectivity pattern differences bilaterally in the cerebellum posterior lobe in healthy subjects after normal sleep and sleep deprivation: a resting-state functional MRI study

    Directory of Open Access Journals (Sweden)

    Liu XM

    2015-05-01

    Full Text Available Xuming Liu,1 Zhihan Yan,2 Tingyu Wang,1 Xiaokai Yang,1 Feng Feng,3 Luping Fan,1 Jian Jiang4 1Department of Radiology, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, 2Department of Radiology, The 2nd Affiliated Hospital of Wenzhou Medical University, Wenzhou, 3Peking Union Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 4Department of Radiology, The First Affiliated Hospital of Nanchang University, Nanchang, People’s Republic of China Objective: The aim of this study was to use functional magnetic resonance imaging (fMRI technique to explore the resting-state functional connectivity (rsFC differences of the bilaterial cerebellum posterior lobe (CPL after normal sleep (NS and after sleep deprivation (SD. Methods: A total of 16 healthy subjects (eight males, eight females underwent an fMRI scan twice at random: once following NS and the other following 24 hours’ SD, with an interval of 1 month between the two scans. The fMRI scanning included resting state and acupuncture stimulation. The special activated regions located during the acupuncture stimulation were selected as regions of interest for rsFC analysis. Results: Bilateral CPLs were positively activated by acupuncture stimulation. In the NS group, the left CPL showed rsFC with the bilateral CPL, bilateral frontal lobe (BFL, left precuneus and right inferior parietal lobule, while the right CPL showed rsFC with the bilateral temporal lobe, right cerebellum anterior lobe, right CPL, left frontal lobe, left anterior cingulate, right posterior cingulate, and bilateral inferior parietal lobule. In the SD group, the left CPL showed rsFC with the left posterior cingulate gyrus bilateral CPL, left precuneus, left precentral gyrus, BFL, and the left parietal lobe, while the right CPL showed rsFC with bilateral cerebellum anterior lobe, bilateral CPL, left frontal lobe and left temporal lobe. Compared with the NS group, the

  19. Punding following posterior cerebral artery infarction: a case report and review of literature

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    Lin CI

    2017-03-01

    Full Text Available Cho-I Lin,1 Yu-Ching Lin,1–3 Wei-Chih Lien,1 Pei-Chun Hsieh,1 Sheng-Han Lin,1 Ta-Shen Kuan1,2 1Department of Physical Medicine and Rehabilitation, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan; 2Department of Physical Medicine and Rehabilitation, College of Medicine, National Cheng Kung University, Tainan, Taiwan; 3Medical Device Innovation Center, National Cheng Kung University, Tainan, Taiwan Introduction: Punding is a complex stereotyped behavior, characterized by excessiveness, non-goal orientation, and repetitiveness. It is mostly associated with Parkinson’s disease, and very few cases in non-Parkinson’s disease have been reported. We report a case of punding associated with supratentorial ischemic stroke.Case presentation: We present a 70-year-old man with left posterior cerebral artery infarction with quetiapine-induced punding manifesting as repetitive unidirectional body turning. Remission of punding behavior ensued after cessation of quetiapine and administration of clonazepam.Conclusion: This case describes the clinical course of quetiapine-induced punding in a patient with left posterior cerebral artery infarction. It suggests clonazepam may serve as a treatment option for poststroke punding. Keywords: punding, stereotyped behavior, stroke, quetiapine, clonazepam

  20. Traumatic Rupture of Posterior Tibial Tendon Following Closed Supination-Adduction Ankle Fracture: A Case Report.

    Science.gov (United States)

    Krishna, Sathya Vamsi; Pilar, Anoop; Pai, Sudhir N; Issac, Thomas

    2016-01-01

    A 25-year-old man with no known comorbidities presented with pain and swelling of the left ankle following a twisting injury that had occurred during a road traffic accident. On examination, a 1 × 1-cm abrasion was noted on the medial malleolus and tenderness was noted over the medial and lateral malleoli. A radiograph of the left ankle revealed a fracture of the medial malleolus and an infrasyndesmotic avulsion fracture of the lateral malleolus (a supination-adduction injury). Immediate surgery was performed for the treatment of the medial malleolar fracture. On exploration, the posterior tibial tendon was found to be severed and frayed 2 cm proximal to the medial malleolar fracture. The medial malleolus was fixed with 2 parallel malleolar screws. The ruptured tendon was explored proximally, and the ends were debrided and repaired. At 1 year of follow-up, the ankle had good union and function of the tendon was restored. Posterior tibial tendon ruptures, although rare, should be suspected in cases of closed ankle fracture, irrespective of the mechanism of injury.

  1. Dexmedetomidine sedation in painful posterior segment surgery

    Directory of Open Access Journals (Sweden)

    Mansour A

    2012-12-01

    Full Text Available Ahmad Mansour,1,2 Samar Taha31Department of Ophthalmology, American University of Beirut, Beirut, Lebanon; 2Rafik Hariri University Hospital, Beirut, Lebanon; 3Department of Anesthesiology, American University of Beirut, Beirut, LebanonPurpose: To present a case series on the use of dexmedetomidine (Precedex sedation in painful posterior segment surgery performed under topical anesthesia, similar to its use in cataract surgery.Methods: A prospective review of cases that had posterior segment surgery under topical anesthesia and that needed sedation. Dexmedetomidine-loading infusion was 1 mcg/kg over 10 minutes, followed by a maintenance infusion (0.5 mcg/kg/h.Results: Nine patients were operated on under topical anesthesia: two scleral buckle, five cryopexy, one scleral laceration, and one pars plana vitrectomy with very dense laser therapy in an albinotic fundus; six patients had retinal detachment. General or local anesthesia were not possible due to medical or ocular morbidities, use of anticoagulants, or the surgery plan changed intraoperatively when new pathologies were discovered. The surgeon achieved good surgical control in eight of nine cases, with one patient having ocular and bodily movements that were disturbing. Six patients had no pain, while three patients reported mild pain. No adverse effects were noted and all patients had successful surgical outcomes. Heart rate, blood pressure, and oxygen saturation were well controlled throughout the procedures. The most frequent adverse reactions of dexmedetomidine reported in the literature in less than 5% (hypotension, bradycardia, and dry mouth were not recorded in the present study.Conclusion: When a surgeon has planned to do a pars plana vitrectomy under topical anesthesia and the surgical situation dictates the addition of cryopexy, scleral buckle, or intense laser retinopexy, then sedation with dexmedetomidine can help in the control of ocular pain in the majority of cases, with good

  2. The left fusiform gyrus hosts trisensory representations of manipulable objects

    DEFF Research Database (Denmark)

    Kassuba, Tanja; Klinge, Corinna; Hölig, Cordula

    2011-01-01

    During object manipulation the brain integrates the visual, auditory, and haptic experience of an object into a unified percept. Previous brain imaging studies have implicated for instance the dorsal part of the lateral occipital complex in visuo-tactile and the posterior superior temporal sulcus....... In the first experiment, we identified brain regions which were consistently activated by unimodal visual, auditory, and haptic processing of manipulable objects relative to non-object control stimuli presented in the same modality. In the second experiment, we assessed regional brain activations when...... participants had to match object-related information that was presented simultaneously in two or all three modalities. Only a well-defined region in left fusiform gyrus (FG) showed an object-specific activation during unisensory processing in the visual, auditory, and tactile modalities. The same region...

  3. Aphasia following left thalamic hemorrhage. A study by Western Aphasia Battery and single photon emission CT

    Energy Technology Data Exchange (ETDEWEB)

    Makishita, Hideo; Miyasaka, Motomaro; Tanizaki, Yoshio; Yanagisawa, Nobuo; Sugishita, Morihiro

    1984-07-01

    A report is given of 7 patients with left thalamic hemorrhage in the chronic stage (from 1.5 months to 4.5 months) in which language disorders were examined by Western Aphasia Battery (WAB) and cerebral blood flow was measured by single photon emission CT. Examination of language by WAB revealed 4 aphasics out of 7 cases, and 3 patients had no language deficit. The patient with Wernicke's aphasia showed low density area only in the left posterior thalamus in X-ray CT, and revealed severe low blood flow area extending to left temporal lobe in emission CT. In the case with transcortical sensory aphasia, although X-ray CT showed no obvious low density area, emission CT revealed moderate low flow area in the left temporooccipital region and low blood flow at the left thalamus. In one of the two patients classified as anomic aphasia, emission CT showed slight low flow area at the temporo-occipital region similar to the case with transcortical sensory aphasia. In another case with anomic aphasia there was a wide low density area all over the left thalamus and midline shift to the right in X-ray CT, and emission CT showed severe low blood flow in the same region spreading widely toward the cerebral surface. In all of the 3 patients without aphasia, emission CT showed low flow region restricted to the left thalamus.

  4. Borders of left gastric lymph node area in 124 patients with esophageal and gastric cardia carcinoma

    International Nuclear Information System (INIS)

    Qian Pudong; Guo Yesong; Li Jianzhong; Wang Yufen; Feng Chunwei; Lv Hong; Fei Wenlong

    2006-01-01

    Objective: To measure and define the distribution of left gastric lymph nodes. Methods: From Jan. 2004 to Apr. 2005, silver clips were set around the root of the left gastric artery in 124 patients with esophageal and gastric cardia carcinoma, X-ray films at 0 degree and 90 degree simulator gantry in the radio- therapeutic position were taken. Then, the data of the superior, lower, left, right, anterior and posterior bor- der in each patient was recorded. With SAS 8.02 software, data of minimum area which covered the left gastric lymph node in different incidences were obtained. Results: According to the analysis of Shapiro-Wilk, Kolmogorov-Smimov, Cramervon Mises and Anderson-Darling tests, each border' was of normal distribution, with equal frequency in the male and female, despite the actual results in different genders. Pearson Correlation Coefficients analysis did not suggest a significant relationship between the border and height, weight and size of vertebrae, which formed the minimum area covering the left gastric area at frequency of 100%, 95%, 90% and 85%, which were drawn out through the calculation. Conclusions: Aiming at completely identifying the normal distribution of the left gastric lymph node, more patients are required to be in the pool. For the time being, location in the left gastric area can be obtained from details of the results in the present study. (authors)

  5. Representation of Semantic Similarity in the Left Intraparietal Sulcus: Functional Magnetic Resonance Imaging Evidence

    Directory of Open Access Journals (Sweden)

    Veerle Neyens

    2017-08-01

    Full Text Available According to a recent study, semantic similarity between concrete entities correlates with the similarity of activity patterns in left middle IPS during category naming. We examined the replicability of this effect under passive viewing conditions, the potential role of visuoperceptual similarity, where the effect is situated compared to regions that have been previously implicated in visuospatial attention, and how it compares to effects of object identity and location. Forty-six subjects participated. Subjects passively viewed pictures from two categories, musical instruments and vehicles. Semantic similarity between entities was estimated based on a concept-feature matrix obtained in more than 1,000 subjects. Visuoperceptual similarity was modeled based on the HMAX model, the AlexNet deep convolutional learning model, and thirdly, based on subjective visuoperceptual similarity ratings. Among the IPS regions examined, only left middle IPS showed a semantic similarity effect. The effect was significant in hIP1, hIP2, and hIP3. Visuoperceptual similarity did not correlate with similarity of activity patterns in left middle IPS. The semantic similarity effect in left middle IPS was significantly stronger than in the right middle IPS and also stronger than in the left or right posterior IPS. The semantic similarity effect was similar to that seen in the angular gyrus. Object identity effects were much more widespread across nearly all parietal areas examined. Location effects were relatively specific for posterior IPS and area 7 bilaterally. To conclude, the current findings replicate the semantic similarity effect in left middle IPS under passive viewing conditions, and demonstrate its anatomical specificity within a cytoarchitectonic reference frame. We propose that the semantic similarity effect in left middle IPS reflects the transient uploading of semantic representations in working memory.

  6. Independent representations of verbs and actions in left lateral temporal cortex.

    Science.gov (United States)

    Peelen, Marius V; Romagno, Domenica; Caramazza, Alfonso

    2012-10-01

    Verbs and nouns differ not only on formal linguistic grounds but also in what they typically refer to: Verbs typically refer to actions, whereas nouns typically refer to objects. Prior neuroimaging studies have revealed that regions in the left lateral temporal cortex (LTC), including the left posterior middle temporal gyrus (pMTG), respond selectively to action verbs relative to object nouns. Other studies have implicated the left pMTG in action knowledge, raising the possibility that verb selectivity in LTC may primarily reflect action-specific semantic features. Here, using functional neuroimaging, we test this hypothesis. Participants performed a simple memory task on visually presented verbs and nouns that described either events (e.g., "he eats" and "the conversation") or states (e.g., "he exists" and "the value"). Verb-selective regions in the left pMTG and the left STS were defined in individual participants by an independent localizer contrast between action verbs and object nouns. Both regions showed equally strong selectivity for event and state verbs relative to semantically matched nouns. The left STS responded more to states than events, whereas there was no difference between states and events in the left pMTG. Finally, whole-brain group analysis revealed that action verbs, relative to state verbs, activated a cluster in pMTG that was located posterior to the verb-selective pMTG clusters. Together, these results indicate that verb selectivity in LTC is independent of action representations. We consider other differences between verbs and nouns that may underlie verb selectivity in LTC, including the verb property of predication.

  7. Elastic K-means using posterior probability.

    Science.gov (United States)

    Zheng, Aihua; Jiang, Bo; Li, Yan; Zhang, Xuehan; Ding, Chris

    2017-01-01

    The widely used K-means clustering is a hard clustering algorithm. Here we propose a Elastic K-means clustering model (EKM) using posterior probability with soft capability where each data point can belong to multiple clusters fractionally and show the benefit of proposed Elastic K-means. Furthermore, in many applications, besides vector attributes information, pairwise relations (graph information) are also available. Thus we integrate EKM with Normalized Cut graph clustering into a single clustering formulation. Finally, we provide several useful matrix inequalities which are useful for matrix formulations of learning models. Based on these results, we prove the correctness and the convergence of EKM algorithms. Experimental results on six benchmark datasets demonstrate the effectiveness of proposed EKM and its integrated model.

  8. Iodine-125 radiation of posterior uveal melanoma

    International Nuclear Information System (INIS)

    Packer, S.

    1987-01-01

    Twenty-eight cases of posterior choroidal melanoma were treated with iodine-125 in gold eye plaques. Eleven cases were located within 3.0 mm of the optic nerve (group A), nine were within 3.0 mm of the fovea (group B), and eight were within 3.0 mm of the optic nerve and fovea (group C). The mean follow-up of group A was 46.3 months; group B, 25.5 months; and group C, 42.7 months. Complications included macular edema, cataract and tumor growth. Visual acuity remained within two lines of that tested preoperatively for 4 of 11 patients in group A, 4 of 9 in group B, and 5 of 8 in group C. These results with iodine-125 suggest it as an appropriate treatment for patients with choroidal melanoma located near optic nerve and/or macula

  9. Iodine-125 radiation of posterior uveal melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Packer, S.

    1987-12-01

    Twenty-eight cases of posterior choroidal melanoma were treated with iodine-125 in gold eye plaques. Eleven cases were located within 3.0 mm of the optic nerve (group A), nine were within 3.0 mm of the fovea (group B), and eight were within 3.0 mm of the optic nerve and fovea (group C). The mean follow-up of group A was 46.3 months; group B, 25.5 months; and group C, 42.7 months. Complications included macular edema, cataract and tumor growth. Visual acuity remained within two lines of that tested preoperatively for 4 of 11 patients in group A, 4 of 9 in group B, and 5 of 8 in group C. These results with iodine-125 suggest it as an appropriate treatment for patients with choroidal melanoma located near optic nerve and/or macula.

  10. Imaging of the posterior pelvic floor

    Energy Technology Data Exchange (ETDEWEB)

    Stoker, Jaap [Department of Radiology, Academic Medical Center, University of Amsterdam (Netherlands); Bartram, Clive I.; Halligan, Steve [Intestinal Imaging Centre, St. Mark' s Hospital, London (United Kingdom)

    2002-04-01

    Disorders of the posterior pelvic floor are relatively common. The role of imaging in this field is increasing, especially in constipation, prolapse and anal incontinence, and currently imaging is an integral part of the investigation of these pelvic floor disorders. Evacuation proctography provides both structural and functional information for rectal voiding and prolapse. Dynamic MRI may be a valuable alternative as the pelvic floor muscles are visualised, and it is currently under evaluation. Endoluminal imaging is important in the management of anal incontinence. Both endosonography and endoanal MRI can be used for detection of anal sphincter defects. Endoanal MRI has the advantage of simultaneously evaluating external sphincter atrophy, which is an important predictive factor for the outcome of sphincter repair. Many aspects of constipation and prolapse remain incompletely understood and treatment is partly empirical; however, imaging has a central role in management to place patients into treatment-defined groups. (orig.)

  11. Imaging of the posterior pelvic floor

    International Nuclear Information System (INIS)

    Stoker, Jaap; Bartram, Clive I.; Halligan, Steve

    2002-01-01

    Disorders of the posterior pelvic floor are relatively common. The role of imaging in this field is increasing, especially in constipation, prolapse and anal incontinence, and currently imaging is an integral part of the investigation of these pelvic floor disorders. Evacuation proctography provides both structural and functional information for rectal voiding and prolapse. Dynamic MRI may be a valuable alternative as the pelvic floor muscles are visualised, and it is currently under evaluation. Endoluminal imaging is important in the management of anal incontinence. Both endosonography and endoanal MRI can be used for detection of anal sphincter defects. Endoanal MRI has the advantage of simultaneously evaluating external sphincter atrophy, which is an important predictive factor for the outcome of sphincter repair. Many aspects of constipation and prolapse remain incompletely understood and treatment is partly empirical; however, imaging has a central role in management to place patients into treatment-defined groups. (orig.)

  12. MR imaging of posterior cruciate ligament injuries

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Nobuyuki [Tsukuba Univ., Ibaraki (Japan). Hospital; Niitsu, Mamoru; Itai, Yuji; Sato, Motohiro; Kujiraoka, Yuka; Ikeda, Kotaro; Kanamori, Akihiro

    2001-07-01

    Posterior cruciate ligament (PCL) injuries are less frequent than anterior cruciate ligament (ACL) injuries, but are presumably more common than once thought. Thirty-nine patients with PCL injuries identified on MR images were studied. The criteria for PCL injury were complete tear, partial tear, and avulsion fracture. The approximate site of a partial tear was categorized as proximal, midsubstance, distal, or combination. Fourteen patients (35.9%) had complete tears of the PCL, 21 patients (53.8%) had partial tears, and four patients (10.3%) had avulsion fractures. A total of 12 patients (30.7%) had isolated PCL injuries, while the remaining 27 patients demonstrated evidence of other coexistent knee injuries, such as meniscal tears and ligamentous injuries. Of coexistent knee injuries, meniscal tears (18 patients, 46.2%) were most often seen. (author)

  13. Tissue characteristics in left ventricular hypertrophy using magnetic resonance imaging

    International Nuclear Information System (INIS)

    Yoshida, Shigeru; Ueno, Yuji; Arita, Mikio; Nishio, Ichiro; Masuyama, Yoshiaki

    1988-01-01

    For 15 normotensive patients with asymmetric septal hypertrophy (ASH), 10 hypertensive patients with concentric hypertrophy (CH), and five normal subjects (N), we examined changes in myocardial T 1 and T 2 values related to the cardiac cycle. The usefulness of those values in differentiating diseases with left ventricular hypertrophy was evaluated. Left ventricular (LV) short-axis spin echo images and inversion recovery images were obtained at endsystolic and diastolic cardiac phases, and T 1 and T 2 images were calculated. The regional wall thickness (WT) and T 1 and T 2 values were measured in the anterior septum, anterior wall, lateral wall, posterior wall and posterior septum. Myocardial T 1 and T 2 values were significantly decreased in systole (T 1 : 185.6±37.9 msec, T 2 : 24.4±6.3 msec, mean±SD) compared to those in diastole (T 1 : 249.2±56.7 msec, T 2 : 31.7±9.4 msec). In both the ASH and CH groups, significant correlations were observed between diastolic T 1 values and WT (ASH: r = 0.80, p 2 values and WT (ASH: r = 0.58, p 1 values in the ASH group (343.4±40.5 msec) were significantly higher than those of the CH group (247.3±21.4 msec), although the mean wall thickness values were similar in both groups. The T 1 /WT and T 2 /WT were significantly lower in the CH group than those in the ASH and N groups. In conclusion, myocardial T 1 and T 2 values were related not only to the cardiac cycle, but to wall thickness and to types of hypertrophy. The T 1 and T 2 values may be useful for distinguishing hypertrophic cardiomyopathy from hypertrophy due to hypertension. (author)

  14. Effects of a 4 month enriched environment on the hippocampus and the myelinated fibers in the hippocampus of middle-aged rats.

    Science.gov (United States)

    Qiu, Xuan; Huang, Chun-Xia; Lu, Wei; Yang, Shu; Li, Chen; Shi, Xiao-Yan; Chen, Lin; Xiu, Yun; Yang, Jun-Qing; Tang, Yong

    2012-07-17

    An enriched environment has been shown to enhance learning and memory and to induce morphological changes in the hippocampus. In the present study, 14-month (middle-aged) female and male Sprague-Dawley rats were randomly divided into enriched environment (EE) rats and standard environment (SE) rats. EE rats were reared in an enriched environment and SE rats were reared in a standard environment for 4 months. The spatial learning capacity was assessed with Morris water maze. The hippocampus and the myelinated fibers in the rat hippocampus were quantitatively investigated with a transmission electronic microscope technique and stereological methods. The female rats housed in an enriched environment showed improved performance in the Morris water maze. There was no significant difference in the total volume of hippocampus between SE rats and EE rats. The total length and total volume of the myelinated fibers in the hippocampus of the female and male EE rats were significantly increased, respectively, when compared to the female and male SE rats. The increase of the total length of the myelinated nerve fibers in the hippocampus was mainly due to the increase of the myelinated fibers with diameters from 0.5 to 0.9 μm. Our results showed that a 4 month enriched environment had significant effects on the spatial learning capacity and the myelinated fibers in the hippocampus of middle-aged rats. The present study might provide an important theoretical basis for searching for an ethological strategy to delay the progress of brain aging in the future. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Systolic left ventricular function according to left ventricular concentricity and dilatation in hypertensive patients

    DEFF Research Database (Denmark)

    Bang, Casper; Gerdts, Eva; Aurigemma, Gerard P

    2013-01-01

    Left ventricular hypertrophy [LVH, high left ventricular mass (LVM)] is traditionally classified as concentric or eccentric based on left ventricular relative wall thickness. We evaluated left ventricular systolic function in a new four-group LVH classification based on left ventricular dilatation...

  16. Impaired learning from errors in cannabis users: Dorsal anterior cingulate cortex and hippocampus hypoactivity.

    Science.gov (United States)

    Carey, Susan E; Nestor, Liam; Jones, Jennifer; Garavan, Hugh; Hester, Robert

    2015-10-01

    The chronic use of cannabis has been associated with error processing dysfunction, in particular, hypoactivity in the dorsal anterior cingulate cortex (dACC) during the processing of cognitive errors. Given the role of such activity in influencing post-error adaptive behaviour, we hypothesised that chronic cannabis users would have significantly poorer learning from errors. Fifteen chronic cannabis users (four females, mean age=22.40 years, SD=4.29) and 15 control participants (two females, mean age=23.27 years, SD=3.67) were administered a paired associate learning task that enabled participants to learn from their errors, during fMRI data collection. Compared with controls, chronic cannabis users showed (i) a lower recall error-correction rate and (ii) hypoactivity in the dACC and left hippocampus during the processing of error-related feedback and re-encoding of the correct response. The difference in error-related dACC activation between cannabis users and healthy controls varied as a function of error type, with the control group showing a significantly greater difference between corrected and repeated errors than the cannabis group. The present results suggest that chronic cannabis users have poorer learning from errors, with the failure to adapt performance associated with hypoactivity in error-related dACC and hippocampal regions. The findings highlight a consequence of performance monitoring dysfunction in drug abuse and the potential consequence this cognitive impairment has for the symptom of failing to learn from negative feedback seen in cannabis and other forms of dependence. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. Minimally invasive surgical approach to treat posterior urethral diverticulum

    Directory of Open Access Journals (Sweden)

    Ossamah Alsowayan

    2015-01-01

    Full Text Available Urethral diverticulum is a localized saccular or fusiform out-pouching of the urethra. It may occur at any point along the urethra in both male and females. Male urethral diverticulum is rare, and could be either congenital or acquired, anterior or posterior. The mainstay treatment of posterior urethral diverticulum (PUD is the open surgical approach. Here we discuss our minimally invasive surgical approach (MIS in managing posterior urethral diverticulum.

  18. Vitamin D deficiency and posterior subcapsular cataract

    Directory of Open Access Journals (Sweden)

    Brown CJ

    2015-06-01

    Full Text Available Craig J Brown,1 Faical Akaichi21The Eye Center, Fayetteville, AR, USA; 2Scotland’s Rural College, Edinburgh, UKPurpose: To evaluate risk factors associated with posterior subcapsular cataract (PSC development and the relationship between vitamin D deficiency and etiology of PSC.Methods: Of 195 consecutive patients from a private ophthalmology practice, diagnosed with PSC, serum vitamin D3 (25-OH D levels were obtained for 175, and associations among risk factors, comorbidities, and PSC were assessed.Results: In all 175 PSC patients, mean 25-OH D levels were low (24 ng/mL ±11 SD compared with age/sex-matched standards. Significant differences in 25-OH D levels were noted between PSC subjects taking/not taking calcium supplements, systemic steroids, osteoporosis medications, etc. Alone, smoking status and calcium channel blockers and/or topical steroids use made no significant difference in PSC subjects 25-OH D levels, but two or more of these factors were associated with lowered levels of 25-OH D (P<0.001. Low vitamin D was correlated with female sex, autoimmune disease, and non-skin cancer diagnosis, but not with age, or other comorbidities or medication use. In five early-stage PSC patients taking 5,000 IU of 25-OH D daily for vitamin D deficiency, there was resolution of their cataracts during the 2-year follow-up period.Conclusion: Vitamin D levels for most PSC patients fell below the 30 ng/mL calcium homeostasis threshold. Some comorbidities and non-ophthalmic interventions are associated with the development of PSC at less depressed levels of 25-OH D. In this series, vitamin D deficiency was associated with PSC cataract, suggesting that raising the level of vitamin D intake may reduce PSC incidence.Keywords: posterior subcapsular, cataracts, vitamin D deficiency, risk factors, hypocalcemia, case report

  19. Disrupted Thalamus White Matter Anatomy and Posterior Default Mode Network Effective Connectivity in Amnestic Mild Cognitive Impairment

    Directory of Open Access Journals (Sweden)

    Thomas Alderson

    2017-11-01

    Full Text Available Alzheimer’s disease (AD and its prodromal state amnestic mild cognitive impairment (aMCI are characterized by widespread abnormalities in inter-areal white matter fiber pathways and parallel disruption of default mode network (DMN resting state functional and effective connectivity. In healthy subjects, DMN and task positive network interaction are modulated by the thalamus suggesting that abnormal task-based DMN deactivation in aMCI may be a consequence of impaired thalamo-cortical white matter circuitry. Thus, this article uses a multimodal approach to assess white matter integrity between thalamus and DMN components and associated effective connectivity in healthy controls (HCs relative to aMCI patients. Twenty-six HC and 20 older adults with aMCI underwent structural, functional and diffusion MRI scanning using the high angular resolution diffusion-weighted acquisition protocol. The DMN of each subject was identified using independent component analysis (ICA and resting state effective connectivity was calculated between thalamus and DMN nodes. White matter integrity changes between thalamus and DMN were investigated with constrained spherical deconvolution (CSD tractography. Significant structural deficits in thalamic white matter projection fibers to posterior DMN components posterior cingulate cortex (PCC and lateral inferior parietal lobe (IPL were identified together with significantly reduced effective connectivity from left thalamus to left IPL. Crucially, impaired thalamo-cortical white matter circuitry correlated with memory performance. Disrupted thalamo-cortical structure was accompanied by significant reductions in IPL and PCC cortico-cortical effective connectivity. No structural deficits were found between DMN nodes. Abnormal posterior DMN activity may be driven by changes in thalamic white matter connectivity; a view supported by the close anatomical and functional association of thalamic nuclei effected by AD pathology and

  20. Disrupted Thalamus White Matter Anatomy and Posterior Default Mode Network Effective Connectivity in Amnestic Mild Cognitive Impairment.

    Science.gov (United States)

    Alderson, Thomas; Kehoe, Elizabeth; Maguire, Liam; Farrell, Dervla; Lawlor, Brian; Kenny, Rose A; Lyons, Declan; Bokde, Arun L W; Coyle, Damien

    2017-01-01

    Alzheimer's disease (AD) and its prodromal state amnestic mild cognitive impairment (aMCI) are characterized by widespread abnormalities in inter-areal white matter fiber pathways and parallel disruption of default mode network (DMN) resting state functional and effective connectivity. In healthy subjects, DMN and task positive network interaction are modulated by the thalamus suggesting that abnormal task-based DMN deactivation in aMCI may be a consequence of impaired thalamo-cortical white matter circuitry. Thus, this article uses a multimodal approach to assess white matter integrity between thalamus and DMN components and associated effective connectivity in healthy controls (HCs) relative to aMCI patients. Twenty-six HC and 20 older adults with aMCI underwent structural, functional and diffusion MRI scanning using the high angular resolution diffusion-weighted acquisition protocol. The DMN of each subject was identified using independent component analysis (ICA) and resting state effective connectivity was calculated between thalamus and DMN nodes. White matter integrity changes between thalamus and DMN were investigated with constrained spherical deconvolution (CSD) tractography. Significant structural deficits in thalamic white matter projection fibers to posterior DMN components posterior cingulate cortex (PCC) and lateral inferior parietal lobe (IPL) were identified together with significantly reduced effective connectivity from left thalamus to left IPL. Crucially, impaired thalamo-cortical white matter circuitry correlated with memory performance. Disrupted thalamo-cortical structure was accompanied by significant reductions in IPL and PCC cortico-cortical effective connectivity. No structural deficits were found between DMN nodes. Abnormal posterior DMN activity may be driven by changes in thalamic white matter connectivity; a view supported by the close anatomical and functional association of thalamic nuclei effected by AD pathology and the posterior