Paraganglioma Syndrome SCHIAVI, FRANCESCA; SAVVOUKIDIS, THEODOROS; TRABALZINI, FRANCO ...
Annals of the New York Academy of Sciences,
08/2006, Volume:
1073, Issue:
1
Journal Article
Peer reviewed
: Paraganglioma syndrome includes head and neck paraganglioma and pheochromocytoma, and is classified according to the three susceptibility genes involved, SDHB, SDHC, and SDHD. This study assessed ...the prevalence of germline mutations in SDHB, SDHC, and SDHD genes in a consecutive population admitted to Padova Hospital consisting of 20 patients with head and neck paraganglioma (HNP). Mutations were identified in the three genes in four affected individuals, three sporadic cases and one with family history of HNP. The novel SDHB p.R242C mutation was identified in a sporadic monolateral carotid body tumor. The SDHC p.Q147X mutation, the first to be described in Italy, was detected in a sporadic monolateral jugulotympanic paraganglioma. The SDHD p.Y114C mutation was identified in two unrelated patients, one familial case of bilateral carotid body tumor and one multiple paraganglioma. SDHB, SDHC, and SDHD molecular screening is important in all HNPs, with or without primary indicators of paraganglioma syndrome, to orient mutation‐driven clinical screening for additional HNPs and pheochromocytoma.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Hippocampus dentate gyrus (DG) is characterized by neuronal plasticity processes in adulthood, and polysialylation of NCAM promotes neuronal plasticity. In previous investigations we found that ...alpha-tocopherol increased the PSA-NCAM-positive granule cell number in adult rat DG, suggesting that alpha-tocopherol may enhance neuronal plasticity. To verify this hypothesis, in the present study, structural remodeling in adult rat DG was investigated under alpha-tocopherol supplementation conditions. PSA-NCAM expression was evaluated by Western blotting, evaluation of PSA-NCAM-positive granule cell density, and morphometric analysis of PSA-NCAM-positive processes. In addition, the optical density of synaptophysin immunoreactivity and the synaptic profile density, examined by electron microscopy, were evaluated. Moreover, considering that PSA-NCAM expression has been found to be related to PKCdelta activity and alpha-tocopherol has been shown to inhibit PKC activity in vitro, Western blotting and immunohistochemistry followed by densitometry were used to analyze PKC. Our results demonstrated that an increase in PSA-NCAM expression and optical density of DG molecular layer synaptophysin immunoreactivity occurred in alpha-tocopherol-treated rats. Electron microscopy analysis showed that the increase in synaptophysin expression was related to an increase in synaptic profile density. In addition, Western blotting revealed a decrease in phospho-PKC Pan and phospho-PKCdelta, demonstrating that alpha-tocopherol is also able to inhibit PKC activity in vivo. Likewise, immunoreactivity for the active form of PKCdelta was lower in alpha-tocopherol-treated rats than in controls, while no changes were found in PKCdelta expression. These results demonstrate that alpha-tocopherol is an exogenous factor affecting neuronal plasticity in adult rat DG, possibly through PKCdelta inhibition.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In the last years, scientists have focused their attention on adult stem cells. It has long been known that stem cells are capable of renewing themselves and that they can generate in multiple cell ...types. Today, there are new evidences that stem cells are present in far more tissues and organs than once thought and that these cells are capable of developing into more kinds of cells than previously imagined. Adult human mesenchymal stem cells (hMSCs) are prime candidates for many cell-based tissue-engineering applications because of their plasticity and easy accessibility. Despite such potential, their use in therapeutic application is still restricted because there are some opens issues which need to be deeply investigated. Here we showed some of the most important studies about the new methodology to track the hMSCs and we demonstrated how to manipulate them thanks to the new advantages offered by the development of nanotechnologies.
Currently, the gold standard to repair large nerve defects is the autologous nerve graft. These solutions offer a mechanical support, adhesion substrates, and, with Schwann cells (SC), a source of ...neurotropic factors for axonal growth. The technical limits are the donor side damage, multiple surgical accesses, and the unavailability of large amounts of grafts. In recent years, several researchers focused their attention on the interaction between cells (nervous and glial) and physic-chemical cues that arise from the extracellular milieu. Nanotechnologies produce surfaces that mimic the topographical signals (physical stimuli) that arise from enterprise content management (ECM) to modulate the forces acting during axonal elongation. The use of magnetic nanoparticles (MNPs) seems to be able to guide and to boost the nerve regeneration. Both research areas could be improved through surfaces functionalization by biological molecules (proteins/peptides, growth factors, etc.). In the future, the aim will be to help recovery after peripheral nerve lesion by producing a tridimensional structured conduit, then repeat the ECM architecture and take advantage of MNPs internalized by cells and guide them through tension forces by external magnetic fields to stimulate and direct axon growing. The aims of this review were to evaluate the findings of studies that used physical stimuli (nanoscaffold surfaces and MNPs) used for peripheral nerve regeneration support. The future trends in the field of peripheral nerve regeneration continue to produce a wide variety of new techniques to improve the opportunity for advances to treat peripheral nerve injuries.
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