478 research outputs found

    Influence of aging on peripheral nervous system: a morphological and morphometric study

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    It is well known that aging influences several functional and structural features of peripheral nerves (Verdù et al., 2000; Ceballos et al., 1999; Jeronimo et al., 2008). However, the role of these changes in the damage/repair mechanisms occurring in acquired peripheral neuropathies is still unclear. To this aim, a multimodal, long-term assessment in a mice model would represent an optimal tool to perform experimental neuropathy studies designed to evaluate the role of aging in relationship with a given nerve injury. In this study we used 40 females one-month-old C57B1/6 mice and we followed-up them for fifteen months. Digital and caudal nerve conduction velocity (NCV) studies were performed monthly to evaluate changes in electrophysiological features; moreover, four animals were sacrificed every two months in order to collect caudal nerve, sciatic nerve, dorsal root ganglia (DRG) and skin for morphological and morphometric analysis. The neurophysiological assessments showed a remarkable increase of caudal NCV until the age of 9 months and then it remained unchanged until the end of the observation period; in the same period, digital NCV increase was also present although less marked. At the pathological level, both caudal and sciatic nerves showed a decrease in fibres density related with age, whereas axon and fibres diameters tended to increase. These preliminary data can be considered a first step aiming at creating a background for future studies on the relationship between aging and peripheral nervous system induced damage

    Making connections: gap junctions are pivotal for MSCinduced long lasting survival of sensory neurons

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    The direct contact of Mesenchymal Stem Cells (MSCs) with Dorsal Root Ganglia sensory neurons is pivotal to prolong the neuronal survival and to support their maturation (1). Here we further investigated the mechanisms underlying this direct contact-mediated positive effect, focusing our attention on the possible interaction between MSCs and neurons, and in particular on gap junction formation. We set up direct co-cultures of MSCs and sensory neurons, and after 30 days we analyzed them. The electron microscopy analysis evidenced the presence of junctions between MSCs and neurons only in direct co-cultures. Using a diffusible dye, Calcein, we demonstrated a direct interaction among cells, with a flow of dye from MSCs to neurons. To confirm the importance of such a connection we blocked it by using a gap junction blocker, the carbenoxolone (2). The use of gap junction blocker induced a decrease of neuronal survival in co-culture, thus demonstrating the important role of gap junctions for the positive effect of MSCs. We are now investigating the possible exchanged molecules, focusing our attention on some pro-survival miRNA, such as miRNA 29b and miRNA 142-5 (3), in order to identify the molecule able to positively affect the neuronal survival

    Untailored vs. Gender- and Body-Mass-Index-Tailored Skeletal Muscle Mass Index (SMI) to Assess Sarcopenia in Advanced Head and Neck Squamous Cell Carcinoma (HNSCC)

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    : (1) background: sarcopenia lasting >1 year might be considered a chronic condition in many HNSCC patients. CT-scan-derived skeletal muscle mass Index (SMI) is an established surrogate of sarcopenia; yet, the cut-off reported in the literature (literature-based, lb-SMI < 43.2) is mainly based on the risk of chemoradiotherapy-induced toxicity, and the optimal value to discriminate OS is under-investigated. (2) methods: the effect on OS of the lb-SMI cutoff was compared with an untailored OS-oriented SMI cutoff obtained in a cohort of consecutive advanced HNSCC patients treated with primary chemoradiotherapy, bio-chemotherapy or chemo-immunotherapy (cohort-specific, cs-SMI cutoff). gender- and BMI-tailored (gt-SMI and bt-SMI) cut-offs were also evaluated. cutoff values were identified by using the maximally selected rank statistics for OS. (3) results: In 115 HNSCC patients, the cs-SMI cutoff was 31.50, which was lower compared to the lb-SMI reported cut-off. the optimal cut-off separately determined in females, males, overweight and non-overweight patients were 46.02, 34.37, 27.32 and 34.73, respectively. gt-SMI categorization had the highest effect on survival (p < 0.0001); its prognostic value was independent of the treatment setting or the primary location and was retained in a multivariate cox-regression analysis for OS including other HNSCC-specific prognostic factors (p = 0.0004). (4) conclusions: a tailored SMI assessment would improve clinical management of sarcopenia in chemoradiotherapy-, bio-chemotherapy- or chemo-immunotherapy-treated HNSCC patients. gender-based SMI could be used for prognostication in HNSCC patients

    A functional gene expression analysis in epithelial sinonasal cancer: Biology and clinical relevance behind three histological subtypes

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    Epithelial sinonasal cancers (SNCs) are rare diseases with overlapping morphological features and a dismal prognosis. We aimed to investigate the expression differences among the histological subtypes for discerning their molecular characteristics. We selected 47 SNCs: (i) 21 nonkeratinizing squamous cell carcinomas (NKSCCs), (ii) 13 sinonasal neuroendocrine cancers (SNECs), and (iii) 13 sinonasal undifferentiated cancers (SNUCs). Gene expression profiling was performed by DASL (cDNA-mediated annealing, selection, extension, and ligation) microarray analysis with internal validation by quantitative RT-PCR (RT-qPCR). Relevant molecular patterns were uncovered by sparse partial-least squares discriminant analysis (sPLS-DA), microenvironment cell type (xCell), CIBERSORT, and gene set enrichment (GSEA) analyses. The first two sPLS-DA components stratified samples by histological subtypes. xCell highlighted increased expression of immune components (CD8 + effector memory cells, in SNUC) and \u201cother cells\u201d: keratinocytes and neurons in NKSCC and SNEC, respectively. Pathway enrichment was observed in NKSCC (six gene sets, proliferation related), SNEC (one gene set, pancreatic \u3b2-cells), and SNUC (twenty gene sets, some of them immune-system related). Major neuroendocrine involvement was observed in all the SNEC samples. Our high-throughput analysis revealed a good diagnostic ability to differentiate NKSCC, SNEC, and SNUC, but indicated that the neuroendocrine pathway, typical and pathognomonic of SNEC is also present at lower expression levels in the other two histological subtypes. The different and specific profiles may be exploited for elucidating their biology and could help to identify prognostic and therapeutic opportunities

    Long-Term Survival of Human Neural Stem Cells in the Ischemic Rat Brain upon Transient Immunosuppression

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    Understanding the physiology of human neural stem cells (hNSCs) in the context of cell therapy for neurodegenerative disorders is of paramount importance, yet large-scale studies are hampered by the slow-expansion rate of these cells. To overcome this issue, we previously established immortal, non-transformed, telencephalic-diencephalic hNSCs (IhNSCs) from the fetal brain. Here, we investigated the fate of these IhNSC's immediate progeny (i.e. neural progenitors; IhNSC-Ps) upon unilateral implantation into the corpus callosum or the hippocampal fissure of adult rat brain, 3 days after global ischemic injury. One month after grafting, approximately one fifth of the IhNSC-Ps had survived and migrated through the corpus callosum, into the cortex or throughout the dentate gyrus of the hippocampus. By the fourth month, they had reached the ipsilateral subventricular zone, CA1-3 hippocampal layers and the controlateral hemisphere. Notably, these results could be accomplished using transient immunosuppression, i.e administering cyclosporine for 15 days following the ischemic event. Furthermore, a concomitant reduction of reactive microglia (Iba1+ cells) and of glial, GFAP+ cells was also observed in the ipsilateral hemisphere as compared to the controlateral one. IhNSC-Ps were not tumorigenic and, upon in vivo engraftment, underwent differentiation into GFAP+ astrocytes, and β-tubulinIII+ or MAP2+ neurons, which displayed GABAergic and GLUTAmatergic markers. Electron microscopy analysis pointed to the formation of mature synaptic contacts between host and donor-derived neurons, showing the full maturation of the IhNSC-P-derived neurons and their likely functional integration into the host tissue. Thus, IhNSC-Ps possess long-term survival and engraftment capacity upon transplantation into the globally injured ischemic brain, into which they can integrate and mature into neurons, even under mild, transient immunosuppressive conditions. Most notably, transplanted IhNSC-P can significantly dampen the inflammatory response in the lesioned host brain. This work further supports hNSCs as a reliable and safe source of cells for transplantation therapy in neurodegenerative disorders

    Caspase-Dependent Inhibition of Mousepox Replication by gzmB

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    BACKGROUND: Ectromelia virus is a natural mouse pathogen, causing mousepox. The cytotoxic T (Tc) cell granule serine-protease, granzyme B, is important for its control, but the underlying mechanism is unknown. Using ex vivo virus immune Tc cells, we have previously shown that granzyme B is able to activate several independent pro-apoptotic pathways, including those mediated by Bid/Bak/Bax and caspases-3/-7, in target cells pulsed with Tc cell determinants. METHODS AND FINDINGS: Here we analysed the physiological relevance of those pro-apoptotic pathways in ectromelia infection, by incubating ectromelia-immune ex vivo Tc cells from granzyme A deficient (GzmB(+) Tc cells) or granzyme A and granzyme B deficient (GzmAxB(-/-) Tc cell) mice with ectromelia-infected target cells. We found that gzmB-induced apoptosis was totally blocked in ectromelia infected or peptide pulsed cells lacking caspases-3/-7. However ectromelia inhibited only partially apoptosis in cells deficient for Bid/Bak/Bax and not at all when both pathways were operative suggesting that the virus is able to interfere with apoptosis induced by gzmB in case not all pathways are activated. Importantly, inhibition of viral replication in vitro, as seen with wild type cells, was not affected by the lack of Bid/Bak/Bax but was significantly reduced in caspase-3/-7-deficient cells. Both caspase dependent processes were strictly dependent on gzmB, since Tc cells, lacking both gzms, neither induced apoptosis nor reduced viral titers. SIGNIFICANCE: Out findings present the first evidence on the biological importance of the independent gzmB-inducible pro-apoptotic pathways in a physiological relevant virus infection model
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