263 research outputs found

    Quantitative Kinematic Characterization of Reaching Impairments in Mice After a Stroke

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    Background and Objective. Kinematic analysis of reaching movements is increasingly used to evaluate upper extremity function after cerebrovascular insults in humans and has also been applied to rodent models. Such analyses can require time-consuming frame-by-frame inspections and are affected by the experimenter's bias. In this study, we introduce a semi-automated algorithm for tracking forepaw movements in mice. This methodology allows us to calculate several kinematic measures for the quantitative assessment of performance in a skilled reaching task before and after a focal cortical stroke. Methods. Mice were trained to reach for food pellets with their preferred paw until asymptotic performance was achieved. Photothrombosis was then applied to induce a focal ischemic injury in the motor cortex, contralateral to the trained limb. Mice were tested again once a week for 30 days. A high frame rate camera was used to record the movements of the paw, which was painted with a nontoxic dye. An algorithm was then applied off-line to track the trajectories and to compute kinematic measures for motor performance evaluation. Results. The tracking algorithm proved to be fast, accurate, and robust. A number of kinematic measures were identified as sensitive indicators of poststroke modifications. Based on end-point measures, ischemic mice appeared to improve their motor performance after 2 weeks. However, kinematic analysis revealed the persistence of specific trajectory adjustments up to 30 days poststroke, indicating the use of compensatory strategies. Conclusions. These results support the use of kinematic analysis in mice as a tool for both detection of poststroke functional impairments and tracking of motor improvements following rehabilitation. Similar studies could be performed in parallel with human studies to exploit the translational value of this skilled reaching analysis

    The Chemokine CCL2 Mediates the Seizure-enhancing Effects of Systemic Inflammation

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    Epilepsy is a chronic disorder characterized by spontaneous recurrent seizures. Brain inflammation is increasingly recognized as a critical factor for seizure precipitation, but the molecular mediators of such proconvulsant effects are only partly understood. The chemokine CCL2 is one of the most elevated inflammatory mediators in patients with pharmacoresistent epilepsy, but its contribution to seizure generation remains unexplored. Here, we show, for the first time, a crucial role for CCL2 and its receptor CCR2 in seizure control. We imposed a systemic inflammatory challenge via lipopolysaccharide (LPS) administration in mice with mesial temporal lobe epilepsy. We found that LPS dramatically increased seizure frequency and upregulated the expression of many inflammatory proteins, including CCL2. To test the proconvulsant role of CCL2, we administered systemically either a CCL2 transcription inhibitor (bindarit) or a selective antagonist of the CCR2 receptor (RS102895). We found that interference with CCL2 signaling potently suppressed LPS-induced seizures. Intracerebral administration of anti-CCL2 antibodies also abrogated LPS-mediated seizure enhancement in chronically epileptic animals. Our results reveal that CCL2 is a key mediator in the molecular pathways that link peripheral inflammation with neuronal hyperexcitability

    Neuroplastic Changes Following Brain Ischemia and their Contribution to Stroke Recovery: Novel Approaches in Neurorehabilitation

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    Ischemic damage to the brain triggers substantial reorganization of spared areas and pathways, which is associated with limited, spontaneous restoration of function. A better understanding of this plastic remodeling is crucial to develop more effective strategies for stroke rehabilitation. In this review article, we discuss advances in the comprehension of post-stroke network reorganization in patients and animal models. We first focus on rodent studies that have shed light on the mechanisms underlying neuronal remodeling in the perilesional area and contralesional hemisphere after motor cortex infarcts. Analysis of electrophysiological data has demonstrated brain-wide alterations in functional connectivity in both hemispheres, well beyond the infarcted area. We then illustrate the potential use of non-invasive brain stimulation (NIBS) techniques to boost recovery. We finally discuss rehabilitative protocols based on robotic devices as a tool to promote endogenous plasticity and functional restoration

    Lymph node fine needle cytology, Epstein Barr virus infection and Hodgkin Lymphoma

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    Epstein-Barr virus (EBV) is a double-strand DNA virus of the herpes family; it is one of the most common human viruses and it is associated with a wide spectrum of benign and malignant conditions. EBV is related to the development of several neoplasms, globally 1% of tumours, including lymphoproliferative, epithelial and mesenchymal neoplasm. Lymphoproliferative disorders include Hodgkin lymphoma (HL) and B and T cell non-Hodgkin lymphoma. HL is one of the most common lymphoma in the developed world, affecting both young people and adults. HL pathogenesis is complex and includes various and partially unknown mechanisms. EBV has been detected in some HL neoplastic cells and expresses genes with a potential oncogenic function, therefore many studies suggest that viral infections have a causative role in neoplastic transformation. Fine Needle Cytology (FNC) is extensively used in the first diagnosis of any lymph-nodal enlargement, including reactive lymphadeno - pathies and lymphoproliferative processes; therefore cytopathologists are likely to encounter EBVassociated malignancies in cytology samples, mainly HL, which is one of the most common lymphoma. This study focuses on the cytological features and ancillary studies required to diagnose EBV-related HL

    Electrophysiology of glioma: a Rho GTPase-activating protein reduces tumor growth and spares neuron structure and function

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    Background. Glioblastomas are the most aggressive type of brain tumor. A successful treatment should aim at halting tumor growth and protecting neuronal cells to prevent functional deficits and cognitive deterioration. Here, we exploited a Rho GTPase-activating bacterial protein toxin, cytotoxic necrotizing factor 1 (CNF1), to interfere with glioma cell growth in vitro and vivo. We also investigated whether this toxin spares neuron structure and function in peritumoral areas. Methods. We performed a microarray transcriptomic and in-depth proteomic analysis to characterize the molecular changes triggered by CNF1 in glioma cells. We also examined tumor cell senescence and growth in vehicle-and CNF1-treated glioma-bearing mice. Electrophysiological and morphological techniques were used to investigate neuronal alterations in peritumoral cortical areas. Results. Administration of CNF1 triggered molecular and morphological hallmarks of senescence in mouse and human glioma cells in vitro. CNF1 treatment in vivo induced glioma cell senescence and potently reduced tumor volumes. In peritumoral areas of glioma-bearing mice, neurons showed a shrunken dendritic arbor and severe functional alterations such as increased spontaneous activity and reduced visual responsiveness. CNF1 treatment enhanced dendritic length and improved several physiological properties of pyramidal neurons, demonstrating functional preservation of the cortical network. Conclusions. Our findings demonstrate that CNF1 reduces glioma volume while at the same time maintaining the physiological and structural properties of peritumoral neurons. These data indicate a promising strategy for the development of more effective antiglioma therapies

    Quaderno Uno : natura, cultura, artificio

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    Nel femminismo la convenzionale distinzione tra natura e cultura \ue8 consumata da tempo. Quali teorie si pongono all\u2019intersezione di tecnologia, arte, scienze naturali e storia del Pianeta? Qual \ue8 il contributo del pensiero femminista al campo dell\u2019ecologia, della biologia, delle tecnologie digitali? Come ripensare la materia e la materialit\ue0 fuori da un determinismo meccanicista? E come interrogare e praticare le scienze come campo d\u2019azione femminista? Stare al presente delle invenzioni pi\uf9 avanzate nel campo della biomedicina, della fisica, della biotecnologia, sapendo intravedere simultaneamente ambiguit\ue0 e linee di fuga, senza rifugiarsi in visioni tecnofobe e neoprimitiviste o \u2013 al contrario \u2013 nel negativo di ipotesi di accelerazione, \ue8 senz\u2019altro una delle sfide del pensiero femminista contemporaneo. Pensare insieme corpo e tecnologia, umano e non-umano, vivente e non-vivente, economie e forme di vita \u2013 il Quaderno Uno tenta una ricognizione delle molte ipotesi che sono gi\ue0 all\u2019opera nelle indagini scientifiche, nelle epistemologie, negli approcci femministi alla bio-medicina, nelle arti come campo di immaginazione politica. Quaderno Uno: natura | cultura | artificio (a cura di EcoPol / Ilenia Caleo) Un manifesto materialista EcoPol, Introduzione | Crocevia | Posizionamento | Tracciati Birgit Mara Kaiser e Kathrin Thiele, Diffrazione: onto-epistemologia, fisica quantistica e critica delle scienze umane Liana Borghi, Percorso per diffrazione Donatella Saroli, \u201cIf you could see what I\u2019ve seen with your eyes\u201d. Sguardi possibili offerti dalle pratiche artistiche Ilenia Caleo, Dentro le turbolenze espressive della materia Olivia Fiorilli, Biomedicina. Affari di donne Beatrice Busi, Luci e ombre della normalizzazione della critica femminista: il caso della biologia del sesso Norma Santi, FREE OUT | Opera Elementale #5 STRUMENTI Laura Felline, Epistemologie femministe EcoPol e Sara Pierallini, Bibliografia ragionata Bionote delle autrici Indice general

    Progression of motor deficits in glioma-bearing mice: impact of CNF1 therapy at symptomatic stages

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    Glioblastoma (GBM) is the most aggressive type of brain tumor. In this context, animal models represent excellent tools for the early detection and longitudinal mapping of neuronal dysfunction, that are critical in the preclinical validation of new therapeutic strategies. In a mouse glioma model, we developed sensitive behavioral readouts that allow early recognizing and following neurological symptoms. We injected GL261 cells into the primary motor cortex of syngenic mice and we used a battery of behavioral tests to longitudinally monitor the dysfunction induced by tumor growth. Grip strength test revealed an early onset of functional deficit associated to the glioma growth, with a significant forelimb weakness appearing 9 days after tumor inoculation. A later deficit was observed in the rotarod and in the grid walk tasks. Using this model, we found reduced tumor growth and maintenance of behavioral functions following treatment with Cytotoxic Necrotizing Factor 1 (CNF1) at a symptomatic stage. Our data provide a detailed and precise examination of how tumor growth reverberates on the behavioral functions of glioma-bearing mice, providing normative data for the study of therapeutic strategies for glioma treatment. The reduced tumor volume and robust functional sparing observed in CNF1-treated, glioma-bearing mice strengthen the notion that CNF1 delivery is a promising strategy for glioma therapy

    Longitudinal Bottom-Up Proteomics of Serum, Serum Extracellular Vesicles, and Cerebrospinal Fluid Reveals Candidate Biomarkers for Early Detection of Glioblastoma in a Murine Model

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    Glioblastoma Multiforme (GBM) is a brain tumor with a poor prognosis and low survival rates. GBM is diagnosed at an advanced stage, so little information is available on the early stage of the disease and few improvements have been made for earlier diagnosis. Longitudinal murine models are a promising platform for biomarker discovery as they allow access to the early stages of the disease. Nevertheless, their use in proteomics has been limited owing to the low sample amount that can be collected at each longitudinal time point. Here we used optimized microproteomics workflows to investigate longitudinal changes in the protein profile of serum, serum small extracellular vesicles (sEVs), and cerebrospinal fluid (CSF) in a GBM murine model. Baseline, pre-symptomatic, and symptomatic tumor stages were determined using non-invasive motor tests. Forty-four proteins displayed significant differences in signal intensities during GBM progression. Dysregulated proteins are involved in cell motility, cell growth, and angiogenesis. Most of the dysregulated proteins already exhibited a difference from baseline at the pre-symptomatic stage of the disease, suggesting that early effects of GBM might be detectable before symptom onset

    Vitamin D(3) protects against Aβ peptide cytotoxicity in differentiated human neuroblastoma SH- SY5Y cells: A role for S1P1/p38MAPK/ATF4 axis.

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    Besides its classical function of bone metabolism regulation, 1alpha, 25-dihydroxyvitamin D3 (1,25(OH)2D3), acts on a variety of tissues including the nervous system, where the hormone plays an important role as neuroprotective, antiproliferating and differentiating agent. Sphingolipids are bioactive lipids that play critical and complex roles in regulating cell fate. In the present paper we have investigated whether sphingolipids are involved in the protective action of 1,25(OH)2D3. We have found that 1,25(OH)2D3 prevents amyloid-β peptide (Aβ(1-42)) cytotoxicity both in differentiated SH-SY5Y human neuroblastoma cells and in vivo. In differentiated SH-SY5Y cells, Aβ(1-42) strongly reduces the sphingosine-1-phosphate (S1P)/ceramide (Cer) ratio while 1,25(OH)2D3 partially reverts this effect. 1,25(OH)2D3 reverts also the Aβ(1-42)-induced reduction of sphingosine kinase activity. We have also studied the crosstalk between 1,25(OH)2D3 and S1P signaling pathways downstream to the activation of S1P receptor subtype S1P1. Notably, we found that 1,25(OH)2D3 prevents the reduction of S1P1 expression promoted by Aβ(1-42) and thereby it modulates the downstream signaling leading to ER stress damage (p38MAPK/ATF4). Similar effects were observed by using ZK191784. In addition, chronic treatment with 1,25(OH)2D3 protects from aggregated Aβ(1-42)-induced damage in the CA1 region of the rat hippocampus and promotes cell proliferation in the hippocampal dentate gyrus of adult mice. In conclusion, these results represent the first evidence of the role of 1,25(OH)2D3 and its structural analogue ZK191784 in counteracting the Aβ(1-42) peptide-induced toxicity through the modulation of S1P/S1P1/p38MAPK/ATF4 pathway in differentiated SH-SY5Y cell
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