123 resultados para BTemporal Lobe Epilepsycopa monnieri


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In addition to functionally affected neuronal signaling pathways, altered axonal, dendritic, and synaptic morphology may contribute to hippocampal hyperexcitability in chronic mesial temporal lobe epilepsies (MTLE). The sclerotic hippocampus in Ammon's horn sclerosis (AHS)-associated MTLE, which shows segmental neuronal cell loss, axonal reorganization, and astrogliosis, would appear particularly susceptible to such changes. To characterize the cellular hippocampal pathology in MTLE, we have analyzed hilar neurons in surgical hippocampus specimens from patients with MTLE. Anatomically well-preserved hippocampal specimens from patients with AHS (n = 44) and from patients with focal temporal lesions (non-AHS; n = 20) were studied using confocal laser scanning microscopy (CFLSM) and electron microscopy (EM). Hippocampal samples from three tumor patients without chronic epilepsies and autopsy samples were used as controls. Using intracellular Lucifer Yellow injection and CFLSM, spiny pyramidal, multipolar, and mossy cells as well as non-spiny multipolar neurons have been identified as major hilar cell types in controls and lesion-associated MTLE specimens. In contrast, none of the hilar neurons from AHS specimens displayed a morphology reminiscent of mossy cells. In AHS, a major portion of the pyramidal and multipolar neurons showed extensive dendritic ramification and periodic nodular swellings of dendritic shafts. EM analysis confirmed the altered cellular morphology, with an accumulation of cytoskeletal filaments and increased numbers of mitochondria as the most prominent findings. To characterize cytoskeletal alterations in hilar neurons further, immunohistochemical reactions for neurofilament proteins (NFP), microtubule-associated proteins, and tau were performed. This analysis specifically identified large and atypical hilar neurons with an accumulation of low weight NFP. Our data demonstrate striking structural alterations in hilar neurons of patients with AHS compared with controls and non-sclerotic MTLE specimens. Such changes may develop during cellular reorganization in the epileptogenic hippocampus and are likely to contribute to the pathogenesis or maintenance of temporal lobe epilepsy.

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BACKGROUND: Visudyne®-mediated photodynamic therapy (PDT) at low drug/light conditions has shown to selectively enhance the uptake of liposomal doxorubicin in subpleural localized sarcoma tumors grown on rodent lungs without causing morphological alterations of the lung. The present experiments explore the impact of low-dose PDT on liposomal doxorubicin (Liporubicin™) uptake to different tumor types grown on rodent lungs. MATERIAL AND METHODS: Three groups of Fischer rats underwent subpleural generation of sarcoma, mesothelioma, or adenocarcinoma tumors on the left lung. At least five animals of each group (sarcoma, n = 5; mesothelioma, n = 7; adenocarcinoma, n = 5) underwent intraoperative low-dose (10 J/cm(2) at 35 mW/cm(2) ) PDT with 0.0625 mg/kg Visudyne® of the tumor and the lower lobe. This was followed by intravenous (IV) administration of 400 µg Liporubicin™. After a circulation time of 60 min, the tumor-bearing lung was processed for HPLC analyses. At least five animals per group underwent the same procedure but without PDT (sarcoma, n = 5; mesothelioma, n = 5; adenocarcinoma, n = 6). Five untreated animals per group underwent CD31 immunostaining of their tumors with histomorphometrical assessment of the tumor vascularization. RESULTS: Low-dose PDT significantly enhanced Liporubicin™ uptake to all tumor types (sarcoma, P = 0.0007; mesothelioma, P = 0.001; adenocarcinoma, P = 0.02) but not to normal lung tissue compared to IV drug administration alone. PDT led to a significantly increased ratio of tumor to lung tissue drug uptake for all three tumor types (P < 0.05). However, the tumor drug uptake varied between tumor types and paralleled tumor vascular density. The vascular density was significantly higher in sarcoma than in adenocarcinoma (P < 0.001) and mesothelioma (P < 0.001), whereas there was no significant difference between adenocarcinoma and mesothelioma. CONCLUSION: Low-dose Visudyne®-mediated PDT selectively enhances the uptake of systemically administered liposomal doxorubicin in tumors without affecting the drug uptake to normal lung. However, drug uptake varied significantly between tumor types and paralleled tumor vascular density.

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Elderly individuals display a rapid age-related increase in intraindividual variability (IIV) of their performances. This phenomenon could reflect subtle changes in frontal lobe integrity. However, structural studies in this field are still missing. To address this issue, we computed an IIV index for a simple reaction time (RT) task and performed magnetic resonance imaging (MRI) including voxel based morphometry (VBM) and the tract based spatial statistics (TBSS) analysis of diffusion tensor imaging (DTI) in 61 adults aged from 22 to 88 years. The age-related IIV increase was associated with decreased fractional anisotropy (FA) as well as increased radial (RD) and mean (MD) diffusion in the main white matter (WM) fiber tracts. In contrast, axial diffusion (AD) and grey matter (GM) densities did not show any significant correlation with IIV. In multivariate models, only FA has an age-independent effect on IIV. These results revealed that WM but not GM changes partly mediated the age-related increase of IIV. They also revealed that the association between WM and IIV could not be only attributed to the damage of frontal lobe circuits but concerned the majority of interhemispheric and intrahemispheric corticocortical connections.

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Summary For the nutritional management of bone health and the prevention of osteoporosis it is important to identify nutrients that positively influence the bone remodeling process at the cellular level. Soy isoflavones show promising osteoprotective effects in animals and humans but their mechanism of action in bone cells is yet poorly understood. Firstly, soy tissue cultures were characterized as a new and optimized source of isoflavones. A large variability in the isoflavone content was observed and high-producing strains (46.3 mg/g dry wt isoflavones) were identified. In the Ishikawa cells bioassay, the estrogenicity of isoflavones was confirmed to be 1000 to 10000 less than 17Mestradiol and that of the malonyl forms was shown for the first time (EC50 of 350 nM and 1880 nM for malonylgenistin and malonyldaidzin, respectively). The estrogenic activity of soya tissue culture extracts correlated to their isoflavone content. Secondly, the effects of phytonutrients on BMP-2 gene expression and on the mevalonate synthesis pathway, as key mediators of bone formation, were investigated. Dietary achievable concentrations of genistein and daidzein (10vM), and statins (4xM) but not 17M estradiol (10nM), induced BMP-2 gene expression (by up to 3-fold) and inhibited the cholesterol biosynthetic pathway (by up to 50%) in the human osteoblastic cell line hP0B¬tert. In addition, several plant extracts (Cyperus rotundus, Lindera benzoin and Cnidium monnieri) induced BMP-2 gene expression but this induction was not restricted to the inhibition of the cholesterol synthesis pathway neither to the estrogenicity. Finally, the gene expression profiles during hP0B-tert differentiation induced by vitamin D and dexamethasone were analyzed with the Affymetrix human GeneChip. 1665 different genes and 98 ESTs were significantly regulated. The expression profiles of bone-related genes was largely in agreement with previously documented patterns, supporting the physiological relevance of the genomic results and the hP0B-tert cell line as a valid model of human osteoblast differentiation. The expression of alternative differentiation markers during the osteogenic treatment of hP0B-tert cells indicated that the adipocyte and myoblast differentiation pathways were repressed, confirming that these culture conditions allowed only osteoblast differentiation. The gene ontology analysis identified further sub-groups of genes that may be involved in the bone formation process. Aims of the thesis In order to define new strategies for the nutritional management of bone health and for the prevention of osteoporosis the major goal of the present work was to investigate the potential of phytonutrients to positively modulate the bone formation process at the cellular level and, in particular: 1.To select and optimise alternative plant sources containing high levels of isoflavones with estrogenic activity (Chapter 3). 2.To compare the effects of statins and phytonutrients on BMP-2 gene expression and on the mevalonate synthesis pathway and to select new plant extracts with a bone anabolic potential (Chapter 4). 3.To further characterize the new human periosteal cell line, hP0B-tert, as a bone- formation model, by elucidating its gene expression profile during differentiation induced by vitamin D and dexamethasone (Chapter 5).

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As future treatments increasingly target the protein chemistry underlying the different dementias, itbecomes crucially important to distinguish between the dementias during life. Neither specific proteinnor genetic markers are as yet available in clinical practice. However, neuroimaging is an obviouscandidate technique that may yield enhanced diagnostic accuracy when applied to thedementias. The physiopathology and anatomopathology is complex in dementia with Lewy bodies(DLB). Besides the relative sparing of medial temporal lobe structures in DLB in comparison toAlzheimer's disease, no clear signature pattern of cerebral atrophy associated with DLB has beenestablished so far. Among others, one reason may be the difficulty in visualizing the small brainnuclei that are differentially involved among the dementias. While we think that structural magneticresonance imaging neuroimaging should be part of the diagnostic workup of most dementia syndromesdue to its usefulness in the differential diagnosis, its contribution to a positive diagnosis ofDLB is as yet limited. The development of different neuroimaging techniques may help distinguishreliably DLB from other neurodegenerative disorders. However, in order to become accepted as partof standard care, these techniques must still prove their effectiveness under routine conditions suchas those encountered by the general practitioner.

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We report the cases of two patients presenting a peculiar speech disorder, which we have named "echoing approval", in which the patients echo, in replying to questions in a dialogue with short phrases, the positive or negative syntactical construction of a question, or its positive or negative intonation, but without any repetition of whole or part of sentences. When asked about their symptoms, the patients replied 80% of the time with "yes, yes", "that's right", or "exactly" to positive questions and "no, no" or "absolutely not" to negative questions, regardless of their actual symptoms and oblivious to self-contradiction. In addition, when the examining doctor was speaking to a medical colleague in the patient's presence and using medical terminology that the patient did not understand, he/she agreed or disagreed with any sentence and technical word uttered in a way entirely dependent on the syntax or intonation used. To distinguish this speech disorder from echolalia or verbal perseverations, with which it may be superficially confused, we suggest that it be called "echoing approval", as it may be part one of the manifestations of the environment-dependency syndrome. This clinical picture was found to be associated with features of transcortical motor aphasia and frontal lobe signs. One patient had a bilateral callosofrontal malignant glioma and the other a probable multiple system atrophy with global deterioration, pre-eminent frontal release signs, diffuse leukoencephalopathy and multiple lacunes. On the basis of these clinical deficits and neuroimaging features, we are unable to delineate the common, or minimal, lesioned network required for this symptomatology to occur, especially in the absence of a series of patients, and with such a difference in both the location and causes of the lesions. However, bilateral frontosubcortical dysfunction was pre-eminent in the clinical picture in both patients, even though more diffuse brain pathology was seen in one, and it might be speculated that dysfunction of the bilateral orbitofrontal and frontomesial motor frontosubcortical circuits might be involved in the aetiology of this peculiar speech disorder.

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The neuropsychological records of 56 patients operated for clipping were studied. Almost every patient remained autonomous and without invalidating motor defect. The present study was aimed at specifying the type and frequency of neuropsychological sequelae and, to a lesser extent, the role of various pathophysiological factors. A main concern was to examine to what extent and at what post-operative interval the neuropsychological assessment can predict the intellectual and socioprofessional outcome of each individual patient. The neuropsychological assessment performed beyond the acute phase showed evidence of intellectual sequelae in about two thirds of the patients. Only one case of permanent anterograde amnesia was observed, probably due to unavoidable inclusion of a hypothalamic artery in the clip during surgery. Transient anterograde amnesia and confabulations were occasionally observed, generally for less than three weeks. A common finding was impaired performance on memory and/or executive tests. In a minority of patients, language disorders, visuoperceptive and visuoconstructive disabilities were found, probably in relation with hemodynamic changes at distance from the aneurysm. Global impairment of intellectual function was not uncommon in the acute post-operative phase but it evolved in most cases towards a more selective impairment, for instance restricted to executive and memory functions, in the chronic phase. The neuropsychological investigation carried out 4 to 15 weeks post-operatively provided satisfactory information about possible long-lasting intellectual disturbances and professional resumption. In particular, persistent global intellectual impairment, persistent amnesia and confabulations 4-15 weeks post-operative were associated with cessation of professional activity; executive and memory impairment, behavioral disturbances such as those encountered in patients with frontal lobe damage were associated with a decreased probability of full-time employment. Pre- and post-operative angiography were not good predictors of long-term cognitive outcome: normal angiography was not necessarily followed by normal neuropsychological outcome, conversely abnormal angiography could be found together with normal neuropsychological outcome. By contrast, there was a relationship between left-lateralised abnormalities on post-operative angiography and occurrence of language disorders; similarly, there was a relationship between side of craniotomy and type of deficits, that is language disorders versus visuoperceptive-visuoconstructive impairments.

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The unstable rock slope, Stampa, above the village of Flåm, Norway, shows signs of both active and postglacial gravitational deformation over an area of 11 km2. Detailed structural field mapping, annual differential Global Navigation Satellite System (GNSS) surveys, as well as geomorphic analysis of high-resolution digital elevation models based on airborne and terrestrial laser scanning indicate that slope deformation is complex and spatially variable. Numerical modeling was used to investigate the influence of former rockslide activity and to better understand the failure mechanism. Field observations, kinematic analysis and numerical modeling indicate a strong structural control of the unstable area. Based on the integration of the above analyses, we propose that the failure mechanism is dominated by (1) a toppling component, (2) subsiding bilinear wedge failure and (3) planar sliding along the foliation at the toe of the unstable slope. Using differential GNSS, 18 points were measured annually over a period of up to 6 years. Two of these points have an average yearly movement of around 10 mm/year. They are located at the frontal cliff on almost completely detached blocks with volumes smaller than 300,000 m3. Large fractures indicate deep-seated gravitational deformation of volumes reaching several 100 million m3, but the movement rates in these areas are below 2 mm/year. Two different lobes of prehistoric rock slope failures were dated with terrestrial cosmogenic nuclides. While the northern lobe gave an average age of 4,300 years BP, the southern one resulted in two different ages (2,400 and 12,000 years BP), which represent most likely multiple rockfall events. This reflects the currently observable deformation style with unstable blocks in the northern part in between Joasete and Furekamben and no distinct blocks but a high rockfall activity around Ramnanosi in the south. With a relative susceptibility analysis it is concluded that small collapses of blocks along the frontal cliff will be more frequent. Larger collapses of free-standing blocks along the cliff with volumes > 100,000 m3, thus large enough to reach the fjord, cannot be ruled out. A larger collapse involving several million m3 is presently considered of very low likelihood.

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A boy with a right congenital hemiparesis due to a left pre-natal middle cerebral artery infarct developed focal epilepsy at 33 months and then an insidious and subsequently more rapid, massive cognitive and behavioural regression with a frontal syndrome between the ages of 4 and 5 years with continuous spike-waves during sleep (CSWS) on the EEG. Both the epilepsy and the CSWS were immediately suppressed by hemispherotomy at the age of 5 years and 4 months. A behavioural-cognitive follow-up prior to hemispherotomy, an per-operative EEG and corticography and serial post-operative neuropsychological assessments were performed until the age of 11 years. The spread of the epileptic activity to the "healthy" frontal region was the cause of the reversible frontal syndrome. A later gradual long-term but incomplete cognitive recovery, with moderate mental disability was documented. This outcome is probably explained by another facet of the epilepsy, namely the structural effects of prolonged epileptic discharges in rapidly developing cerebral networks which are, at the same time undergoing the reorganization imposed by a unilateral early hemispheric lesion. Group studies on the outcome of children before and after hemispherectomy using only single IQ measures, pre- and post-operatively, may miss particular epileptic cognitive dysfunctions as they are likely to be different from case to case. Such detailed and rarely available complementary clinical and EEG data obtained in a single case at different time periods in relation to the epilepsy, including per-operative electrophysiological findings, may help to understand the different cognitive deficits and recovery profiles and the limits of full cognitive recovery.

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The preclinical Alzheimer's disease (AD) - amnestic mild cognitive impairment (MCI) - is manifested by phenotypes classified into exclusively memory (single-domain) MCI (sMCI) and multiple-domain MCI (mMCI). We suggest that typical MCI-to-AD progression occurs through the sMCI-to-mMCI sequence as a result of the extension of initial pathological processes. To support this hypothesis, we assess myelin content with a Magnetization Transfer Ratio (MTR) in 21 sMCI and 21 mMCI patients and in 42 age-, sex-, and education-matched controls. A conjunction analysis revealed MTR reduction shared by sMCI and mMCI groups in the medial temporal lobe and posterior structures including white matter (WM: splenium, posterior corona radiata) and gray matter (GM: hippocampus; parahippocampal and lingual gyri). A disjunction analysis showed the spread of demyelination to prefrontal WM and insula GM in executive mMCI. Our findings suggest that demyelination starts in the structures affected by neurofibrillary pathology; its presence correlates with the clinical picture and indicates the method of MCI-to-AD progression. In vivo staging of preclinical AD can be developed in terms of WM/GM demyelination.

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Rolandic epilepsy (RE) is the most common idiopathic focal childhood epilepsy. Its molecular basis is largely unknown and a complex genetic etiology is assumed in the majority of affected individuals. The present study tested whether six large recurrent copy number variants at 1q21, 15q11.2, 15q13.3, 16p11.2, 16p13.11 and 22q11.2 previously associated with neurodevelopmental disorders also increase risk of RE. Our association analyses revealed a significant excess of the 600 kb genomic duplication at the 16p11.2 locus (chr16: 29.5-30.1 Mb) in 393 unrelated patients with typical (n = 339) and atypical (ARE; n = 54) RE compared with the prevalence in 65,046 European population controls (5/393 cases versus 32/65,046 controls; Fisher's exact test P = 2.83 × 10(-6), odds ratio = 26.2, 95% confidence interval: 7.9-68.2). In contrast, the 16p11.2 duplication was not detected in 1738 European epilepsy patients with either temporal lobe epilepsy (n = 330) and genetic generalized epilepsies (n = 1408), suggesting a selective enrichment of the 16p11.2 duplication in idiopathic focal childhood epilepsies (Fisher's exact test P = 2.1 × 10(-4)). In a subsequent screen among children carrying the 16p11.2 600 kb rearrangement we identified three patients with RE-spectrum epilepsies in 117 duplication carriers (2.6%) but none in 202 carriers of the reciprocal deletion. Our results suggest that the 16p11.2 duplication represents a significant genetic risk factor for typical and atypical RE.

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An unusual association of a meningioma and an arteriovenous malformation is reported. A 68-year-old man developed left homonymous hemianopsia, left hemiparesis, and gaze palsy. Magnetic resonance imaging showed a right occipital mass lesion containing multiple signal-void areas with tubular and honeycomb appearance, suggesting a marked vascular component. An angiogram showed abnormal vasculature in the mass supplied by the posterior cerebral artery and a dural arteriovenous malformation on the tentorium. Neuropathological examination after total removal of the mass revealed a meningothelial meningioma including major portions of an arteriovenous malformation that extended from the dura and leptomeninges, through the meningioma, and into the occipital lobe, where the tumor was located.

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BACKGROUND: Patients with resectable hilar cholangiocarcinoma often present obstructive jaundice and a small future remnant liver (FRL) ratio. A sequential approach comprising preoperative biliary drainage followed by portal vein embolization (PVE) is usually performed but leads to long preoperative management (6-12 weeks) before patients can undergo resection. To simplify and shorten this phase of liver preparation, we developed a new preoperative approach that involves percutaneous biliary drainage and PVE during the same procedure. We report the outcomes of this combined procedure. METHODS: During 1 year, four patients underwent simultaneous biliary drainage and PVE followed 1 month later by surgical resection of hilar cholangiocarcinoma. Liver volumes were assessed by CT before, and 1, and 3 months after the combined procedure. Serum liver enzymes were assessed before and 1 month after the combined procedure. RESULTS: The combined procedure was feasible in all cases, with no related complications. After the combined procedure, transaminases remained stable or decreased, whereas gamma-glutamyl-transpeptidase, alkaline phosphatase, and bilirubin decreased. During the first month, the left lobe volume increased by +27.9 % (range 19-40.9 %). The FRL ratio increased from 24.9 to 33.2 %. All patients underwent R0 liver resection with a favorable postoperative outcome. The remnant liver volume increased by +132 % (range 78-245 %) between 1 and 3 months. CONCLUSIONS: Simultaneous percutaneous biliary drainage and PVE is feasible. This all-in-one preoperative approach greatly decreases waiting time until surgical resection. These encouraging results warrant further investigation to confirm the safety and to evaluate the reduction in the dropout rate for liver resection in this tumor with poor prognosis.

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Pantomimes of object use require accurate representations of movements and a selection of the most task-relevant gestures. Prominent models of praxis, corroborated by functional neuroimaging studies, predict a critical role for left parietal cortices in pantomime and advance that these areas store representations of tool use. In contrast, lesion data points to the involvement of left inferior frontal areas, suggesting that defective selection of movement features is the cause of pantomime errors. We conducted a large-scale voxel-based lesion-symptom mapping analyses with configural/spatial (CS) and body-part-as-object (BPO) pantomime errors of 150 left and right brain-damaged patients. Our results confirm the left hemisphere dominance in pantomime. Both types of error were associated with damage to left inferior frontal regions in tumor and stroke patients. While CS pantomime errors were associated with left temporoparietal lesions in both stroke and tumor patients, these errors appeared less associated with parietal areas in stroke than in tumor patients and less associated with temporal in tumor than stroke patients. BPO errors were associated with left inferior frontal lesions in both tumor and stroke patients. Collectively, our results reveal a left intrahemispheric dissociation for various aspects of pantomime, but with an unspecific role for inferior frontal regions.