Search results for "glia"

Circolazione di MRSA in età pediatrica in ambiente ospedaliero e in comunità

2013

Introduzione. Negli ultimi anni si è assistito ad un generale incremento e ad una sempre più estesa diffusione, sia in ambito ospedaliero che comunitario, di microrganismi multiresistenti. In assenza ed in attesa di trattamenti farmacologici efficaci maggiore attenzione deve essere impiegata alla realizzazione di strategie di sorveglianza mirate. Il primo isolamento di un ceppo di Staphylococcus aureus meticillinoresistente (MRSA) risale al 1961 e fu seguito da una repentina diffusione negli ospedali di tutto il mondo. Ad oggi MRSA è riconosciuto come uno dei principali agenti responsabili delle infezioni nosocomiali e le percentuali di isolamento variano da Paese in Paese in maniera notevo…

Maestri castigliani di area cantábrica nella Sicilia tra XV e XVI secolo

2014

Il cantiere siciliano tra XV e XVI secolo è multietnico. A fianco di artefici locali, le fonti documentarie rivelano l’attività di un numero consistente di maestri di area genovese, lombarda, campana, ma anche di operatori maiorchini, catalani, valenciani. Forse minoritari, ma comunque degni di attenzione, sono i casi di maestri di area castigliana o cantabrica, che saranno oggetto di questo saggio, la cui attività sull'isola è documentata a partire dal XV secolo. Da molti punti di vista la mobilità e la compresenza di operatori di provenienza diversa si presta a individuare ricadute di natura differente: dai linguaggi e le tecniche ai termini usati nel cantiere e ai comportamenti. Come spe…

artt. 677, 679 e 680 c.p.p.

2008

Generalization of seizures parallels the formation of "dark" neurons in the hippocampus and pontine reticular formation after focal-cortical applicat…

2008

Abstract Distribution and time course of the occurrence of “dark” neurons were compared with the EEG activity and behavior of rats during 4-aminopyridine (4-AP) induced epileptic seizures. A crystal of the K + channel blocker 4-AP (0.5 mg/kg) was placed onto the exposed parieto-occipital cortex of Halothane-anesthetized rats for 40 min. Thereafter, the anesthesia was discontinued and the behavioral signs of the epileptic seizure activity were observed. The presence of “dark” neurons was demonstrated by the sensitive silver method of Gallyas in rats sacrificed at 0, 3 and 6 h after the end of the 4-AP crystal application. The EEG activity was recorded in the rats with longer survival times. …

Active acetylcholine receptors prevent the atrophy of skeletal muscles and favor reinnervation

2020

Denervation of skeletal muscles induces severe muscle atrophy, which is preceded by cellular alterations such as increased plasma membrane permeability, reduced resting membrane potential and accelerated protein catabolism. The factors that induce these changes remain unknown. Conversely, functional recovery following denervation depends on successful reinnervation. Here, we show that activation of nicotinic acetylcholine receptors (nAChRs) by quantal release of acetylcholine (ACh) from motoneurons is sufficient to prevent changes induced by denervation. Using in vitro assays, ACh and non-hydrolysable ACh analogs repressed the expression of connexin43 and connexin45 hemichannels, which prom…

Cellular composition and organization of the spinal cord central canal during metamorphosis of the frogXenopus laevis

2017

Studying the cellular composition and morphological changes of cells lining the central canal during Xenopus laevis metamorphosis could contribute to understand postnatal development and spinal cord regeneration. Here we report the analysis of central canal cells at different stages during metamorphosis using immunofluorescence for protein markers expression, transmission and scanning electron microscopy and cell proliferation assays. The central canal was regionalized according to expression of glial markers, ultrastructure, and proliferation in dorsal, lateral, and ventral domains with differences between larvae and froglets. In regenerative larvae, all cell types were uniciliated, have a…

Injured Axons Instruct Schwann Cells to Build Constricting Actin Spheres to Accelerate Axonal Disintegration

2019

Summary: After a peripheral nerve lesion, distal ends of injured axons disintegrate into small fragments that are subsequently cleared by Schwann cells and later by macrophages. Axonal debris clearing is an early step of the repair process that facilitates regeneration. We show here that Schwann cells promote distal cut axon disintegration for timely clearing. By combining cell-based and in vivo models of nerve lesion with mouse genetics, we show that this mechanism is induced by distal cut axons, which signal to Schwann cells through PlGF mediating the activation and upregulation of VEGFR1 in Schwann cells. In turn, VEGFR1 activates Pak1, leading to the formation of constricting actomyosin…

Bi- and uniciliated ependymal cells define continuous floor-plate-derived tanycytic territories

2017

Multiciliated ependymal (E1) cells line the brain ventricles and are essential for brain homeostasis. We previously identified in the lateral ventricles a rare ependymal subpopulation (E2) with only two cilia and unique basal bodies. Here we show that E2 cells form a distinct biciliated epithelium extending along the ventral third into the fourth ventricle. In the third ventricle floor, apical profiles with only primary cilia define an additional uniciliated (E3) epithelium. E2 and E3 cells' ultrastructure, marker expression and basal processes indicate that they correspond to subtypes of tanycytes. Using sonic hedgehog lineage tracing, we show that the third and fourth ventricle E2 and E3 …

Bi-allelic LoF NRROS Variants Impairing Active TGF-β1 Delivery Cause a Severe Infantile-Onset Neurodegenerative Condition with Intracranial Calcifica…

2020

Negative regulator of reactive oxygen species (NRROS) is a leucine-rich repeat-containing protein that uniquely associates with latent transforming growth factor beta-1 (TGF- β1) and anchors it on the cell surface; this anchoring is required for activation of TGF-β1 in macrophages and microglia. We report six individuals from four families with bi-allelic variants in NRROS. All affected individuals had neurodegenerative disease with refractory epilepsy, developmental regression, and reduced white matter volume with delayed myelination. The clinical course in affected individuals began with normal development or mild developmental delay, and the onset of seizures occurred within the first ye…

SETD7 mediates spinal microgliosis and neuropathic pain in a rat model of peripheral nerve injury

2019

Abstract Gene transcription regulation is critical for the development of spinal microgliosis and neuropathic pain after peripheral nerve injury. Using a model of chronic constriction injury (CCI) of the sciatic nerve, this study characterized the role of SET domain containing lysine methyltransferase 7 (SETD7) which monomethylates histone H3 lysine 4 (H3K4me1), a marker for active gene transcription. SETD7 protein expression in the spinal dorsal horn ipsilateral to nerve lesion was increased from one day to 14 days after CCI, concomitantly with the expression of inflammatory genes, Ccl2, Il-6 and Il-1β. The CCI-induced SETD7 expression was predominantly localized to microglia, as demonstra…