Search results for "nerve"
showing 10 items of 1683 documents
Influence of different approaches to the cerebellopontine angle on the function of the intermediate nerve
2007
Object Surgery in the cerebellopontine angle (CPA) is a standard procedure at many centers. Outcome is focused mainly on preservation of hearing and facial function postoperatively. The nonmotor part of the facial nerve, the intermediate nerve, is nearly neglected nowadays. Methods A retrospective study was designed, including a questionnaire that was sent to 178 patients who had undergone surgery between 2000 and 2004. Data were obtained in 156 cases. The questionnaire was divided into five parts assessing the presence of increased tearing, reduced tearing, salivation disturbances, increased nasal secretions, and abnormalities in taste. Finally, a self-assessment of patient symptoms was a…
Horizontal visibility graphs: exact results for random time series
2009
The visibility algorithm has been recently introduced as a mapping between time series and complex networks. This procedure allows us to apply methods of complex network theory for characterizing time series. In this work we present the horizontal visibility algorithm, a geometrically simpler and analytically solvable version of our former algorithm, focusing on the mapping of random series (series of independent identically distributed random variables). After presenting some properties of the algorithm, we present exact results on the topological properties of graphs associated with random series, namely, the degree distribution, the clustering coefficient, and the mean path length. We sh…
Infracyanine Green vs. Brilliant Blue G in Inverted Flap Surgery for Large Macular Holes: A Long-Term Swept-Source OCT Analysis
2020
Background and Objectives: To compare the long-term toxicity of infracyanine green (IFCG) to brilliant blue G (BBG) in inverted internal limiting membrane flap surgery (I-ILMFS) for large, full-thickness macular holes (FTMHs). Materials and Methods: Prospective randomized study including 39 eyes with &ge
Immunfluorescence study of neuropeptides in identified neurons of the rat auditory superior olivary complex.
1999
The present study was conducted to investigate the distribution and immunohistochemical characteristics of ascending and descending projection neurons of the rat superior olivary complex (SOC), a group of interrelated brainstem nuclei. Ascending neurons were identified by injection of cholera toxin B subunit (CTB) into the central nucleus of the inferior colliculus (IC), descending neurons were labeled by application of Fluoro-Gold (FG) into the scala tympani of the cochlea, ipsilaterally to the IC injection. In accordance with the literature, we observed neurons innervating the IC located in the lateral superior olivary nucleus (LSO) and dorsal periolivary groups (DPO) on both sides, in th…
Cytokines and Neurotrophins Interact in Normal and Diseased States
2006
Neurotrophins (NTs) such as nerve growth factor (NGF) as well as cytokines, for example, interleukin-6 (IL-6), are communicators between the nervous and immune systems. There is evidence for mutual interactions between NTs and cytokines. Strategies are being developed to elucidate the molecular mechanism/s of interactions and to understand how cytokines are involved in health and disease. Analysis of underlying signaling pathways in glial cells indicates that different transcription factors, such as NF-kappa B, cAMP-responsive-element binding protein (CREB), and activator protein 1 (AP-1), are involved in NT induction. IL-6 and NTs of the NGF family are coexpressed at sites of nerve injury.…
Phenothiazines interfere with dopaminergic neurodegeneration in Caenorhabditis elegans models of Parkinson's disease
2010
Oxidative stress is involved in the pathogenesis of various neurodegenerative disorders, conventional antioxidant strategies have yet been of limited success. We have employed transgenic Caenorhabditis elegans expressing DsRed2 in dopaminergic neurons and CFP pan-neuronally, to characterize in larval and adult animals the effects of rotenone and 1-methyl-4-phenyl-pyridinium (MPP(+)) on the dopaminergic system. Investigating the antioxidant phenothiazine and different derived antipsychotic drugs, it was found that free phenothiazine exerted strong neuroprotection at the cellular level and resulted in a better performance in behavioral assays, whereas apomorphine and other dopamine agonists o…
Concurrent TMS-fMRI for causal network perturbation and proof of target engagement
2021
The experimental manipulation of neural activity by neurostimulation techniques overcomes the inherent limitations of correlative recordings, enabling the researcher to investigate causal brain-behavior relationships. But only when stimulation and recordings are combined, the direct impact of the stimulation on neural activity can be evaluated. In humans, this can be achieved non-invasively through the concurrent combination of transcranial magnetic stimulation (TMS) with functional magnetic resonance imaging (fMRI). Concurrent TMS-fMRI allows the assessment of the neurovascular responses evoked by TMS with excellent spatial resolution and full-brain coverage. This enables the functional ma…
Inactivation and tachyphylaxis of heat-evoked inward currents in nociceptive primary sensory neurones of rats.
2000
In contrast to other sensory modalities, pain does not decrease when a noxious stimulus is applied at constant intensity (Greene & Hardy, 1962). From this lack of adaptation on the perceptive level it has traditionally been implied that primary nociceptive afferents also do not adapt upon constant stimulation. This is in contrast to the results of recordings from these afferents, which exhibit pronounced adaptation for physical as well as chemical stimuli (Meyer et al. 1994). Peripheral adaptation of nociceptive nerve endings is compensated by central summation (Mendell & Wall, 1965; Price et al. 1977); this slow summation process of small fibre input to the dorsal horn of the spinal cord i…
Modulation of NMDA receptor function by cyclic AMP in cerebellar neurones in culture
2004
The signal transduction pathways involved in NMDA receptor modulation by other receptors remain unclear. cAMP could be involved in this modulation. The aim of this work was to analyse the contribution of cAMP to NMDA receptor modulation in cerebellar neurones in culture. Forskolin increases cAMP and results in increased intracellular calcium and cGMP that are prevented by blocking NMDA receptors. Similar effects were induced by two cAMP analogues, indicating that cAMP leads to NMDA receptor activation. It has been reported that phosphorylation of Ser897 of the NR1 subunit of NMDA receptors by cAMP-dependent protein kinase (PKA) activates the receptors. Forskolin increases Ser897 phosphoryla…
Regulation of Acetylcholine Synthesis and Release in the Isolated Heart
1981
In the two decades following Loewi’s work (8,9) on the frog heart several research groups tried to use the isolated heart preparation from higher vertebrates for further investigations on synthesis, release and inactivation of acetylcholine (ACh). However the results were discouraging because the overflow of ACh during vagal stimulation was near, or below, the limit of the assay.