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Epithelial tumors of the thyroid are cytogenetically well-investigated tumors. So far, the main cytogenetic subgroups, characterized by trisomy 7 and by rearrangements of either 19q13 or 2p21, respectively, have been described. Recently, we have been able to describe the involvement of a novel gene called THADA in benign thyroid lesions with 2p21 rearrangements. Other fusion genes found in thyroid lesions are RET/PTC and PAX8/PPAR(gamma). The latter occurs in follicular thyroid carcinomas with a t(2;3)(q13;p25). Here we present molecular-cytogenetic and cytogenetic investigations on a follicular thyroid adenoma with a t(2;20;3)(p21;q11.2; p25). In this case, an intronic sequence of PPAR(gamma) is fused to exon 28 of THADA. We used BAC clones containing the genomic sequence of PPARgamma for fluorescence in situ hybridization to confirm the localization of the breakpoint within intron 2 of PPAR(gamma) . Our findings suggest that the close surrounding of PPAR(gamma) is a breakpoint hot spot region, leading to recurrent alterations of this gene in thyroid tumors of follicular origin including carcinomas as well as adenomas with or without involvement of PAX8. 相似文献
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F Sebastiano G Di Gennaro V Esposito A Picardi R Morace A Sparano A Mascia C Colonnese G Cantore P P Quarato 《Clinical neurophysiology》2006,117(2):341-347
OBJECTIVES: To evaluate a novel method for localization of subdural electrodes in presurgical assessment of patients with drug-resistant focal epilepsy. METHODS: We studied eight consecutive patients with posterior epilepsy in whom subdural electrodes were implanted for presurgical evaluation. Electrodes were detected on post-implantation brain CT scans through a semiautomated procedure based on a MATLAB routine. Then, post-implantation CT scans were fused with pre-implantation MRI to localize the electrodes in relation to the underlying cortical structures. The reliability of this procedure was tested by comparing 3D-rendered MR images of the electrodes with electrode position as determined by intraoperative digital photography. RESULTS: In each patient, all electrodes could be correctly localized and visualized in a stereotactic space, thus allowing optimal surgery planning. The agreement between the procedure-generated images and the digital photographs was good according to two independent raters. The mean mismatch between the 3D images and the photographs was 2 mm. CONCLUSIONS: While our findings need confirmation on larger samples including patients with anterior epilepsy, this procedure allowed to localize subdural electrodes and to establish the spatial relationship of each electrode to the underlying brain structure, either normal or damaged, on brain convessity, basal and medial cortex. SIGNIFICANCE: Being simple, rapid, unexpensive, and reliable, this procedure holds promise to be useful to optimize epilepsy surgery planning. 相似文献
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Bethe A Scalettar 《The Neuroscientist》2006,12(2):164-176
Neurons and related cell types often contain two major classes of neurosecretory vesicles, synaptic vesicles (SVs) and dense-core granules (DCGs), which store and release distinct cargo. SVs store and release classic neurotransmitters, which facilitate propagation of action potentials across the synaptic cleft, whereas DCGs transport, store, and release hormones, proteins, and neuropeptides, which facilitate neuronal survival, synaptic transmission, and learning. Over the past few years, there has been a major surge in our understanding of many of the key molecular mechanisms underlying cargo release from SVs and DCGs. This surge has been driven largely by the use of fluorescence microscopy (especially total internal reflection fluorescence microscopy) to visualize SVs or DCGs in living cells. This review highlights some of the recent insights into cargo release from neurosecretory vesicles provided by fluorescence microscopy, with emphasis on DCGs. 相似文献