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151.
Giuseppe M. V. Barbagallo Rosario Caltabiano Giuseppe Parisi Vincenzo Albanese Salvatore Lanzafame 《European spine journal》2009,18(Z2):186-190
Ependymomas account for 2–6% of all central nervous system neoplasms. They develop from the ependymal cells that line the
ventricular cavities of the brain and the central canal of the spinal cord, as well as from ependymal clusters in the filum
terminale. Giant cell ependymoma (GCE) is a rare subtype, with few cases reported, mostly in the brain. We describe the case
of a cervical spinal cord ependymoma with pleomorphic giant cells and focal calcifications occurring in a 25-year-old woman.
Magnetic resonance imaging revealed a large multicystic and partially enhancing intramedullary tumour extending from C2 to
C5. Intraoperative analysis of frozen section tissue fragments suggested a malignant tumour; however, an obvious cleavage
plane was present around most of the mass, and a macroscopically complete tumour removal could be achieved. Subsequently,
paraffin sections and immunohistochemical investigations revealed unequivocal evidence of a GCE with focal calcifications.
This case, the second giant-cell ependymoma to be described in the spinal cord and the first with focal calcifications, highlights
the features of GCE and the discrepancy between the worrisome histological appearance, the surgical findings and the clinical
relatively good prognosis. 相似文献
152.
153.
Water channels (aquaporins) family members have been identified in central nervous system cells. A classic method to measure membrane water permeability and its regulation is to capture and analyse images of Xenopus laevis oocytes expressing them. Laboratories dedicated to the analysis of motion images usually have powerful equipment valued in thousands of dollars. However, some scientists consider that new approaches are needed to reduce costs in scientific labs, especially in developing countries. The objective of this work is to share a very low-cost hardware and software setup based on a well-selected webcam, a hand-made adapter to a microscope and the use of free software to measure membrane water permeability in Xenopus oocytes. One of the main purposes of this setup is to maintain a high level of quality in images obtained at brief intervals (shorter than 70 ms). The presented setup helps to economize without sacrificing image analysis requirements. 相似文献
154.
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156.
Depression is a feature of both Lewy body disorders and multiple system atrophy (MSA). Since serotonergic neurons of the rostral
raphe have been implicated in depression, we sought to determine whether there is a differential involvement of these neurons
in cases with clinically diagnosed dementia with Lewy bodies (DLB) or MSA. We studied the brainstem obtained at autopsy from
fourteen patients with diagnosis of DLB and pathological limbic or neocortical stage Lewy body disease, 13 patients with clinical
and neuropathological diagnosis of MSA, and 12 controls with no history of neurologic disease. The clinical features of these
patients were analyzed retrospectively by reviewing their medical records. Serial sections were immunostained for tryptophan
hydroxylase (TrOH) and α-synuclein and cell counts were performed in the dorsal raphe (DR), median raphe (MR) and medullary
raphe nuclei. There was loss of serotonergic cells in both the DR and MR in DLB compared to control cases: For the DR, the
number of cells/section were 53 ± 6 in DLB versus 159 ± 13 (P < 0.001) respectively, and for the MR 70 ± 11 in DLB versus 173 ± 23 (P < 0.001) respectively. In contrast, these cells were relatively preserved in MSA. The caudal raphe groups were affected both
in MSA and in DLB. There is a differential involvement of raphe neurons in DLB and MSA. Although loss of rostral raphe neurons
may contribute to depression in DLB, this appears to be less likely in MSA. Factors other than the neurochemical phenotype
determine neuronal vulnerability in MSA. 相似文献
157.
Differentiated pediatric thyroid cancer: correlates with adult disease, controversies in treatment 总被引:10,自引:0,他引:10
The biologic behavior of differentiated thyroid cancer can differ between adults and children, especially in those children younger than 10 years of age. Unlike adults, young children typically present with advanced disease at diagnosis. Despite this, children respond rapidly to therapy and have an excellent prognosis that is significantly better than that of their adult counterparts with advanced disease. In contradistinction to adults, children with thyroid cancer also have higher local and distant disease recurrences with progression-free survival of only 70% at 5 years, mandating life-long surveillance. Although thyroid cancer is the most common carcinoma in children, overall incidence is low, a factor that has prevented performance of a controlled, randomized, prospective study to determine the most efficacious treatment regimen in this age group. So, although extensively investigated, treatment of pediatric patients with differentiated thyroid cancer remains controversial. This article reviews the current controversies in the treatment of pediatric differentiated thyroid cancer, focusing on issues of optimal initial and subsequent therapy as well as that of long-term follow-up. Our approach to treatment is presented. In so doing, similarities and differences between adults and children with differentiated thyroid cancer as regards unique considerations in epidemiology, diagnosis, staging, treatment, therapy-related late effects, and disease surveillance are presented. The expanding use of and appropriate roles for thyrogen and fluorine-18-fluorodeoxyglucose positron emission tomography in disease evaluation and surveillance will be addressed. 相似文献
158.
159.
Maria-Giovanna Parisi Hui Li Mylène Toubiana Nicolò Parrinello Matteo Cammarata Philippe Roch 《Molecular immunology》2009,46(3):384-392
Diversity of mRNAs from mytilin B, one of the five mytilins identified in the Mediterranean mussel, Mytilus galloprovincialis, has been investigated from circulating hemocytes. One mussel expressed simultaneously two to ten different mytilin B mRNAs as observed in denaturing gradient gel electrophoresis (DGGE), defining 10 individual DGGE patterns (named A to J) within the mussels from Messina, Sicily (Italy). Three patterns accounted for 79% of the individuals whereas other patterns were found in only 2–7% of the 57 analyzed mussels. Base mutations were observed at specific locations, mainly within COOH-terminus and 3′UTR, leading to 36 nucleotide sequence variants and 21 different coding sequences (cds) segregating in two different clusters. Most of the base mutations were silent, and the number of pro-peptide variants was restricted to four. Finally, as the two amino acid replacements occurred within COOH-terminus, mature peptide from mytilin B appeared unique. Multiple sequencing of partial mytilin B gene from one mussel revealed that one to four randomly distributed mutation points occurred within intron-3. Only one sequence out of the 91 analyzed contained 16 mutation points. In addition, this sequence was the only one containing four out of the six mutation points occurring within exon-4, that code for most of the COOH-terminus domain, including the unique amino acid replacement. Statistical tests for neutrality indicated negative selection pressure on signal and mature peptide domains, but possible positive selection pressure for COOH-terminus domain. 相似文献
160.
Kelley BJ Haidar W Boeve BF Baker M Graff-Radford NR Krefft T Frank AR Jack CR Shiung M Knopman DS Josephs KA Parashos SA Rademakers R Hutton M Pickering-Brown S Adamson J Kuntz KM Dickson DW Parisi JE Smith GE Ivnik RJ Petersen RC 《Neurobiology of aging》2009,30(5):739-751
Mutations in progranulin (PGRN) are associated with frontotemporal dementia with or without parkinsonism. We describe the prominent phenotypic variability within and among eight kindreds evaluated at Mayo Clinic Rochester and/or Mayo Clinic Jacksonville in whom mutations in PGRN were found. All available clinical, genetic, neuroimaging and neuropathologic data was reviewed. Age of onset ranged from 49 to 88 years and disease duration ranged from 1 to 14 years. Clinical diagnoses included frontotemporal dementia (FTD), primary progressive aphasia, FTD with parkinsonism, parkinsonism, corticobasal syndrome, Alzheimer's disease, amnestic mild cognitive impairment, and others. One kindred exhibited maximal right cerebral hemispheric atrophy in all four affected individuals, while another had maximal left hemisphere involvement in all three of the affected. Neuropathologic examination of 13 subjects revealed frontotemporal lobar degeneration with ubiquitin-positive inclusions plus neuronal intranuclear inclusions in all cases. Age of onset, clinical phenotypes and MRI findings associated with most PGRN mutations varied significantly both within and among kindreds. Some kindreds with PGRN mutations exhibited lateralized topography of degeneration across all affected individuals. 相似文献