Search results for "nerve"

Long-range intralaminar noise correlations in the barrel cortex

2015

Identifying the properties of correlations in the firing of neocortical neurons is central to our understanding of cortical information processing. It has been generally assumed, by virtue of the columnar organization of the neocortex, that the firing of neurons residing in a certain vertical domain is highly correlated. On the other hand, firing correlations between neurons steeply decline with horizontal distance. Technical difficulties in sampling neurons with sufficient spatial information have precluded the critical evaluation of these notions. We used 128-channel “silicon probes” to examine the spike-count noise correlations during spontaneous activity between multiple neurons with i…

Influence of rubrospinal tract and the adjacent mesencephalic reticular formation on the activity of medullary respiratory neurons and the phrenic ne…

1988

Suprapontine brain sites acting on the central respiratory system have been demonstrated to give rise to inspiratory as well as expiratory facilitatory effects. In the present study the inspiratory inhibitory effect which has been reported in the cat to be elicited consistently by electrical stimulation of the rubrospinal tract and the adjacent mesencephalic reticular formation was examined in the urethane-anaesthetized rabbit. Stimulation of these sites with single electrical shocks of moderate intensity induced a short latency (onset after 3.0 ms) transient (duration: 29 ms) inhibition of the phrenic nerve activity (PHR). Short volleys of stimuli applied in mid- to late-inspiration led to…

Using Diffusion Tensor Imaging to Evaluate Microstructural Changes and Outcomes after Radiofrequency Rhizotomy of Trigeminal Nerves in Patients with …

2016

Trigeminal neuralgia is characterized by facial pain that may be sudden, intense, and recurrent. Our aim was to investigate microstructural tissue changes of the trigeminal nerve in patients with trigeminal neuralgia resulting from neurovascular compression by diffusion tensor imaging, and to test the predictive value of diffusion tensor imaging for determining outcomes after radiofrequency rhizotomy. Forty-three patients with trigeminal neuralgia were recruited, and diffusion tensor imaging was performed before radiofrequency rhizotomy. By selecting the cisternal segment of the trigeminal nerve manually, we measured the volume of trigeminal nerve, fractional anisotropy, apparent diffusion …

Comparative study of serine-plasmalogens in human retina and optic nerve: identification of atypical species with odd carbon chains

2012

International audience; The objective of this work was to detect and identify phosphatidylserine plasmalogen species in human ocular neurons represented by the retina and the optic nerve. Plasmalogens (vinyl-ether bearing phospholipids) are commonly found in the forms of phosphatidylcholine and phosphatidylethanolamine in numerous mammalian cell types, including the retina. While their biological functions are still unclear, the alteration of cellular plasmalogen content has been associated with several human disorders such as Rhizomelic Chondrodysplasia Punctata Type 2 and Primary Open-Angle Glaucoma.By using liquid-chromatography coupled to high resolution and tandem mass spectrometry, we…

Robot-assisted ascending-descending laparoscopic nerve-sparing prostatectomy

2009

Increased Hypoxic Tolerance by Chemical Inhibition of Oxidative Phosphorylation: “Chemical Preconditioning”

1997

A short ischemic episode preceding sustained ischemia is known to increase tolerance against ischemic cell death. We report early-onset long-lasting neuroprotection against in vitro hypoxia by preceding selective chemical inhibition of oxidative phosphorylation: “chemical preconditioning.” The amplitude of CA1population spikes (psap) in hippocampal slices prepared from control animals (control slices) was 31 ± 27% (mean ± SD) upon 45-min recovery from 15-min in vitro hypoxia. In slices prepared from animals treated in vivo with 20 mg/kg 3-nitropropionate (3-np) 1–24 h prior to slice preparation (preconditioned slices), psap improved to 90 ± 15% (p < 0.01). Posthypoxic oxygen free radical…

In toxic demyelination oligodendroglial cell death occurs early and is FAS independent

2010

Oligodendroglial cell death is a frequent phenomenon of many neurological diseases, e.g. in demyelinating diseases such as multiple sclerosis (MS). The underlying mechanisms are largely unknown. Here, we demonstrate that in the toxic demyelination cuprizone model, oligodendroglial cell death and downregulation of myelin genes start days after initiation of the cuprizone diet and weeks before demyelination is obvious. In early – but not in later – stages, dying oligodendrocytes express activated caspase 3, suggesting a switch from classical apoptotic pathways to caspase 3-independent mechanisms during the course of the cuprizone diet. The expression level of FAS in the corpus callosum, a cel…

Regulation of X-Chromosome-Linked Inhibitor of Apoptosis Protein in Kainic Acid-Induced Neuronal Death in the Rat Hippocampus

2001

XIAP (X-chromosome-linked inhibitor of apoptosis protein) is an antiapoptotic protein which inhibits the activity of caspases and suppresses cell death. However, little is known about the presence and function of XIAP in the nervous system. Here we report that XIAP mRNA is expressed in developing and adult rat brain. Using a specific antibody, we observed XIAP-immunoreactive cells in different brain regions, among others, in the hippocampus and cerebral cortex. Kainic acid, which induces delayed cell death of specific neurons, increased the levels of XIAP in the CA3 region of hippocampus. XIAP was, however, largely absent in cells undergoing cell death, as shown by TUNEL labeling and staini…

Proneurotrophin Binding to P75 Neurotrophin Receptor (P75ntr) Is Essential for Brain Lesion Formation and Functional Impairment after Experimental Tr…

2015

Traumatic brain injury (TBI) initiates an excessive mediator release of e.g. neurotrophins, which promote neuronal survival, differentiation, and modulate synaptic plasticity. Paradoxically, mature forms of neurotrophins promote neuronal survival, whereas unprocessed forms of neurotrophins induce cell death through p75 neurotrophin receptor (p75NTR) signaling. p75NTR is widely expressed during synaptogenesis and is subsequently downregulated in adulthood. Repair mechanisms after acute cerebral insults can reactivate its expression. Therefore, the influence of p75NTR on secondary brain damage was addressed. mRNA levels of p75NTR and its ligands were quantified in brain tissue up to 7 days af…

Pudendal nerve branch injury during radical perineal prostatectomy

2005

We report the first case of direct surgical injury to a pudendal nerve branch during radical perineal prostatectomy. A 65-year-old patient presented with typical symptoms of a pudendal nerve lesion after radical perineal prostatectomy. As the patient did not respond to conservative treatment, surgical exploration and exeresis of the injured sensory branch of the pudendal nerve was necessary, resulting in pain improvement. Urologic surgeons should be aware of the typical symptoms after iatrogenic injury to the pudendal nerve or its branches. Early diagnosis and neurosurgical intervention are important to obtain a more favorable outcome.