Sensory and motor innervation of the crural diaphragm by the vagus nerves.

Science.gov (United States)

Young, Richard L; Page, Amanda J; Cooper, Nicole J; Frisby, Claudine L; Blackshaw, L Ashley

2010-03-01

During gastroesophageal reflux, transient lower esophageal sphincter relaxation and crural diaphragm (CD) inhibition occur concomitantly. Modifying vagus nerve control of transient lower esophageal sphincter relaxation is a major focus of development of therapeutics for gastroesophageal reflux disease, but neural mechanisms that coordinate the CD are poorly understood. Nerve tracing and immunolabeling were used to assess innervation of the diaphragm and lower esophageal sphincter in ferrets. Mechanosensory responses of vagal afferents in the CD and electromyography responses of the CD were recorded in novel in vitro preparations and in vivo. Retrograde tracing revealed a unique population of vagal CD sensory neurons in nodose ganglia and CD motor neurons in brainstem vagal nuclei. Anterograde tracing revealed specialized vagal endings in the CD and phrenoesophageal ligament-sites of vagal afferent mechanosensitivity recorded in vitro. Spontaneous electromyography activity persisted in the CD following bilateral phrenicotomy in vivo, while vagus nerve stimulation evoked electromyography responses in the CD in vitro and in vivo. We conclude that vagal sensory and motor neurons functionally innervate the CD and phrenoesophageal ligament. CD vagal afferents show mechanosensitivity to distortion of the gastroesophageal junction, while vagal motor neurons innervate both CD and distal esophagus and may represent a common substrate for motor control of the reflux barrier. Copyright 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.

Cutaneous lesions sensory impairment recovery and nerve regeneration in leprosy patients

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Ximena Illarramendi

2012-12-01

Full Text Available It is important to understand the mechanisms that enable peripheral neurons to regenerate after nerve injury in order to identify methods of improving this regeneration. Therefore, we studied nerve regeneration and sensory impairment recovery in the cutaneous lesions of leprosy patients (LPs before and after treatment with multidrug therapy (MDT. The skin lesion sensory test results were compared to the histopathological and immunohistochemical protein gene product (PGP 9.5 and the p75 nerve growth factor receptors (NGFr findings. The cutaneous neural occupation ratio (CNOR was evaluated for both neural markers. Thermal and pain sensations were the most frequently affected functions at the first visit and the most frequently recovered functions after MDT. The presence of a high cutaneous nerve damage index did not prevent the recovery of any type of sensory function. The CNOR was calculated for each biopsy, according to the presence of PGP and NGFr-immunostained fibres and it was not significantly different before or after the MDT. We observed a variable influence of MDT in the recovery from sensory impairment in the cutaneous lesions of LPs. Nociception and cold thermosensation were the most recovered sensations. The recovery of sensation in the skin lesions appeared to be associated with subsiding inflammation rather than with the regenerative activity of nerve fibres.

Sensory nerve conduction in the caudal nerves of rats with diabetes Condução nervosa sensorial no nervo caudal de ratos com diabetes experimental

OpenAIRE

Celina Cordeiro de Carvalho; Juliana Netto Maia; Otávio Gomes Lins; Sílvia Regina Arruda de Moraes

2011-01-01

PURPOSE: To investigate sensory nerve conduction of the caudal nerve in normal and diabetic rats. METHODS: Diabetes was induced in twenty 8-weeks old Wistar male rats. Twenty normal rats served as controls. Caudal nerve conduction studies were made before diabetes induction and the end of each week for six consecutive weeks. The caudal nerve was stimulated distally and nerve potentials were recorded proximally on the animal's tail using common "alligator" clips as surface electrodes. RESULTS:...

Functional recovery of denervated skeletal muscle with sensory or mixed nerve protection: a pilot study.

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Qing Tian Li

Full Text Available Functional recovery is usually poor following peripheral nerve injury when reinnervation is delayed. Early innervation by sensory nerve has been indicated to prevent atrophy of the denervated muscle. It is hypothesized that early protection with sensory axons is adequate to improve functional recovery of skeletal muscle following prolonged denervation of mixed nerve injury. In this study, four groups of rats received surgical denervation of the tibial nerve. The proximal and distal stumps of the tibial nerve were ligated in all animals except for those in the immediate repair group. The experimental groups underwent denervation with nerve protection of peroneal nerve (mixed protection or sural nerve (sensory protection. The experimental and unprotected groups had a stage II surgery in which the trimmed proximal and distal tibial nerve stumps were sutured together. After 3 months of recovery, electrophysiological, histological and morphometric parameters were assessed. It was detected that the significant muscle atrophy and a good preserved structure of the muscle were observed in the unprotected and protective experimental groups, respectively. Significantly fewer numbers of regenerated myelinated axons were observed in the sensory-protected group. Enhanced recovery in the mixed protection group was indicated by the results of the muscle contraction force tests, regenerated myelinated fiber, and the results of the histological analysis. Our results suggest that early axons protection by mixed nerve may complement sensory axons which are required for promoting functional recovery of the denervated muscle natively innervated by mixed nerve.

Immunohistochemical Mapping of Sensory Nerve Endings in the Human Triangular Fibrocartilage Complex.

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Rein, Susanne; Semisch, Manuel; Garcia-Elias, Marc; Lluch, Alex; Zwipp, Hans; Hagert, Elisabet

2015-10-01

The triangular fibrocartilage complex is the main stabilizer of the distal radioulnar joint. While static joint stability is constituted by osseous and ligamentous integrity, the dynamic aspects of joint stability chiefly concern proprioceptive control of the compressive and directional muscular forces acting on the joint. Therefore, an investigation of the pattern and types of sensory nerve endings gives more insight in dynamic distal radioulnar joint stability. We aimed to (1) analyze the general distribution of sensory nerve endings and blood vessels; (2) examine interstructural distribution of sensory nerve endings and blood vessels; (3) compare the number and types of mechanoreceptors in each part; and (4) analyze intrastructural distribution of nerve endings at different tissue depth. The subsheath of the extensor carpi ulnaris tendon sheath, the ulnocarpal meniscoid, the articular disc, the dorsal and volar radioulnar ligaments, and the ulnolunate and ulnotriquetral ligaments were dissected from 11 human cadaver wrists. Sensory nerve endings were counted in five levels per specimen as total cell amount/cm(2) after staining with low-affinity neurotrophin receptor p75, protein gene product 9.5, and S-100 protein and thereafter classified according to Freeman and Wyke. All types of sensory corpuscles were found in the various structures of the triangular fibrocartilage complex with the exception of the ulnolunate ligament, which contained only Golgi-like endings, free nerve endings, and unclassifiable corpuscles. The articular disc had only free nerve endings. Furthermore, free nerve endings were the predominant sensory nerve ending (median, 72.6/cm(2); range, 0-469.4/cm(2)) and more prevalent than all other types of mechanoreceptors: Ruffini (median, 0; range, 0-5.6/cm(2); difference of medians, 72.6; p fibrocartilage complex (p ≤ 0.001, respectively) except the ulnolunate ligament. More blood vessels were seen in the volar radioulnar ligament (median, 363

Stimulation of the sensory pudendal nerve increases bladder capacity in the rat.

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Hokanson, James A; Langdale, Christopher L; Sridhar, Arun; Grill, Warren M

2018-04-01

Pudendal nerve stimulation is a promising treatment approach for lower urinary tract dysfunction, including symptoms of overactive bladder. Despite some promising clinical studies, there remain many unknowns as to how best to stimulate the pudendal nerve to maximize therapeutic efficacy. We quantified changes in bladder capacity and voiding efficiency during single-fill cystometry in response to electrical stimulation of the sensory branch of the pudendal nerve in urethane-anesthetized female Wistar rats. Increases in bladder capacity were dependent on both stimulation amplitude and rate. Stimulation that produced increases in bladder capacity also led to reductions in voiding efficiency. Also, there was a stimulation carryover effect, and increases in bladder capacity persisted during several nonstimulated trials following stimulated trials. Intravesically administered PGE 2 reduced bladder capacity, producing a model of overactive bladder (OAB), and sensory pudendal nerve stimulation again increased bladder capacity but also reduced voiding efficiency. This study serves as a basis for future studies that seek to maximize the therapeutic efficacy of sensory pudendal nerve stimulation for the symptoms of OAB.

Peripheral nervous system maturation in preterm infants: longitudinal motor and sensory nerve conduction studies.

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Lori, S; Bertini, Giovanna; Bastianelli, M; Gabbanini, S; Gualandi, D; Molesti, E; Dani, C

2018-04-10

To study the evolution of sensory-motor nerves in the upper and lower limbs in neurologically healthy preterm infants and to use sensory-motor studies to compare the rate of maturation in preterm infants at term age and full-term healthy neonates. The study comprised 26 neurologically normal preterm infants born at 23-33 weeks of gestational age, who underwent sensory nerve conduction and motor nerve conduction studies from plantar medial and median nerves and from tibial and ulnar nerves, respectively. We repeated the same neurophysiological studies in 19 of the preterm infants every 2 weeks until postnatal term age. The data from the preterm infants at term was matched with a group of ten full-term babies a few days after birth. The motor nerve conduction velocity of the tibial and ulnar nerves showed progressive increases in values in relation to gestational age, but there was a decrease of values in distal latencies and F wave latencies. Similarly, there was a gradual increase of sensory nerve conduction velocity values of the medial plantar and median nerves and decreases in latencies in relation to gestational age. At term age, the preterm infants showed significantly lower values of conduction velocities and distal latencies than the full-term neonates. These results were probably because the preterm infants had significantly lower weights, total length and, in particular, distal segments of the limbs at term age. The sensory-motor conduction parameters were clearly related to gestational age, but extrauterine life did not affect the maturation of the peripheral nervous system in the very preterm babies who were neurologically healthy.

Outcomes of short-gap sensory nerve injuries reconstructed with processed nerve allografts from a multicenter registry study.

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Rinker, Brian D; Ingari, John V; Greenberg, Jeffrey A; Thayer, Wesley P; Safa, Bauback; Buncke, Gregory M

2015-06-01

Short-gap digital nerve injuries are a common surgical problem, but the optimal treatment modality is unknown. A multicenter database was queried and analyzed to determine the outcomes of nerve gap reconstructions between 5 and 15 mm with processed nerve allograft. The current RANGER registry is designed to continuously monitor and compile injury, repair, safety, and outcomes data. Centers followed their own standard of care for treatment and follow-up. The database was queried for digital nerve injuries with a gap between 5 and 15 mm reporting sufficient follow-up data to complete outcomes analysis. Available quantitative outcome measures were reviewed and reported. Meaningful recovery was defined by the Medical Research Council Classification (MRCC) scale at S3-S4 for sensory function. Sufficient follow-up data were available for 24 subjects (37 repairs) in the prescribed gap range. Mean age was 43 years (range, 23-81). Mean gap was 11 ± 3 (5-15) mm. Time to repair was 13 ± 42 (0-215) days. There were 25 lacerations, 8 avulsion/amputations, 2 gunshots, 1 crush injury, and 1 injury of unknown mechanism. Meaningful recovery, defined as S3-S4 on the MRCC scales, was reported in 92% of repairs. Sensory recovery of S3+ or S4 was observed in 84% of repairs. Static 2PD was 7.1 ± 2.9 mm (n = 19). Return to light touch was observed in 23 out of 32 repairs reporting Semmes-Weinstein monofilament outcomes (SWMF). There were no reported nerve adverse events. Sensory outcomes for processed nerve allografts were equivalent to historical controls for nerve autograft and exceed those of conduit. Processed nerve allografts provide an effective solution for short-gap digital nerve reconstructions. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Compound sensory action potential in normal and pathological human nerves

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Krarup, Christian

2004-01-01

The compound sensory nerve action potential (SNAP) is the result of phase summation and cancellation of single fiber potentials (SFAPs) with amplitudes that depend on fiber diameter, and the amplitude and shape of the SNAP is determined by the distribution of fiber diameters. Conduction velocities...... dispersion over increasing conduction distance is greater for the SNAP than CMAP, and demonstration of conduction block is therefore difficult. In addition, the effect of temporal dispersion on amplitude and shape is strongly dependent on the number of conducting fibers and their distribution, and......, with fiber loss or increased conduction velocity variability changes of the SNAP may be smaller than expected from normal nerve. The biophysical characteristics of sensory and motor fibers differ, and this may to some extent determine divergent pathophysiological changes in sensory and motor fibers...

Sensory adaptation to electrical stimulation of the somatosensory nerves.

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Graczyk, Emily Lauren; Delhaye, Benoit; Schiefer, Matthew A; Bensmaia, Sliman J; Tyler, Dustin J

2018-03-19

Sensory systems adapt their sensitivity to ambient stimulation levels to improve their responsiveness to changes in stimulation. The sense of touch is also subject to adaptation, as evidenced by the desensitization produced by prolonged vibratory stimulation of the skin. Electrical stimulation of nerves elicits tactile sensations that can convey feedback for bionic limbs. In this study, we investigate whether artificial touch is also subject to adaptation, despite the fact that the peripheral mechanotransducers are bypassed. Approach: Using well-established psychophysical paradigms, we characterize the time course and magnitude of sensory adaptation caused by extended electrical stimulation of the residual somatosensory nerves in three human amputees implanted with cuff electrodes. Main results: We find that electrical stimulation of the nerve also induces perceptual adaptation that recovers after cessation of the stimulus. The time course and magnitude of electrically-induced adaptation are equivalent to their mechanically-induced counterparts. Significance: We conclude that, in natural touch, the process of mechanotransduction is not required for adaptation, and artificial touch naturally experiences adaptation-induced adjustments of the dynamic range of sensations. Further, as it does for native hands, adaptation confers to bionic hands enhanced sensitivity to changes in stimulation and thus a more natural sensory experience. . Creative Commons Attribution license.

Clitoral Epidermal Inclusion Cyst Resection With Intraoperative Sensory Nerve Mapping Technique.

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Wu, Cindy; Damitz, Lynn; Karrat, Kimberly M; Mintz, Alice; Zolnoun, Denniz

2016-01-01

Despite the ever increasing popularity of labial and clitoral surgeries, the best practices and long-term effects of reconstructive procedures in these regions remain unknown. This is particularly noteworthy because the presentation of nerve-related symptoms may be delayed up to a year. Despite the convention that these surgical procedures are low risk, little is known about the best practices that may reduce the postoperative complications as a result of these reconstructive surgeries. We describe a preoperative sensory mapping technique in the context of a symptomatic inclusion cyst in the clitoral region. This technique delineates anatomical and functional regions innervated by the dorsal clitoral nerve while minimizing the vascular watershed area in the midline. A prototypical case of a patient with a clitoral mass is discussed with clinical history and surgical approach. Prior to surgical excision, the dorsal clitoral nerve distribution was mapped in order to avoid a surgical incision in this sensual zone. In our practice, preoperative sensory mapping is a clinically useful planning tool that requires minimal instrumentation and no additional operating time. Sensory mapping allows identification of the functional zone innervated by the dorsal clitoral nerve, which can aid in minimizing damage to the area.

Sensory outcome of fingertip replantations without nerve repair.

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Ozcelik, Ismail Bulent; Tuncer, Serdar; Purisa, Husrev; Sezer, Ilker; Mersa, Berkan; Kabakas, Fatih; Celikdelen, Pinar

2008-01-01

The sensory recovery outcomes of fingertip replantations without nerve repair were retrospectively studied. Between 2000 and 2006, 112 fingertip replantations with only arterial repair were carried out in 98 patients. About 76 of the replants survived totally, with a success rate of 67.8%. Evaluation of sensory recovery was possible in 31 patients (38 replantations). Sensory evaluation was made with Semmes-Weinstein, static and dynamic two-point discrimination, and vibration sense tests. Fingertip atrophy, nail deformities, and return to work were also evaluated. According to the Semmes-Weinstein test, 29.0% (11/38) of the fingers had normal sense, 60.5% (23/38) had diminished light touch, 7.9% (3/38) had diminished protective sensation, and 2.6% (1/38) had loss of protective sensation. Mean static and dynamic two-point discriminations were 7.2 mm (3-11 mm), and 4.60 mm (3-6 mm), respectively. Vibratory testing revealed increased vibration in 42.1% of the fingers, decreased vibration in 36.8%, and equal vibration when compared with the non-injured fingers in 21.1%. Atrophy was present in 14 (36.8%) fingers and negatively affected the results. Nail deformities, cold intolerance, return to work, and the effect of sensory education were investigated. Comparison of crush and clean cut injuries did not yield any significant difference in any of the parameters. Patients who received sensory education had significantly better results in sensory testing. The results were classified as excellent, good, and poor based on results of two-point discrimination tests. The outcome was excellent in 18 fingers and good in 20 fingers. Overall, satisfactory sensory recovery was achieved in fingertip replantations without nerve repair. (c) 2008 Wiley-Liss, Inc.

Comparison of the fastest regenerating motor and sensory myelinated axons in the same peripheral nerve

DEFF Research Database (Denmark)

Moldovan, Mihai; Sørensen, Jesper; Krarup, Christian

2006-01-01

Functional outcome after peripheral nerve regeneration is often poor, particularly involving nerve injuries far from their targets. Comparison of sensory and motor axon regeneration before target reinnervation is not possible in the clinical setting, and previous experimental studies addressing...... the question of differences in growth rates of different nerve fibre populations led to conflicting results. We developed an animal model to compare growth and maturation of the fastest growing sensory and motor fibres within the same mixed nerve after Wallerian degeneration. Regeneration of cat tibial nerve...... after crush (n = 13) and section (n = 7) was monitored for up to 140 days, using implanted cuff electrodes placed around the sciatic and tibial nerves and wire electrodes at plantar muscles. To distinguish between sensory and motor fibres, recordings were carried out from L6-S2 spinal roots using cuff...

Distribution of sensory nerve endings around the human sinus tarsi: a cadaver study

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Rein, Susanne; Manthey, Suzanne; Zwipp, Hans; Witt, Andreas

2014-01-01

The aim of this study was to analyse the pattern of sensory nerve endings and blood vessels around the sinus tarsi. The superficial and deep parts of the fat pads at the inferior extensor retinaculum (IER) as well as the subtalar joint capsule inside the sinus tarsi from 13 cadaver feet were dissected. The distribution of the sensory nerve endings and blood vessels were analysed in the resected specimens as the number per cm2 after staining with haematoxylin-eosin, S100 protein, low-affinity neurotrophin receptor p75, and protein gene product 9.5 using the classification of Freeman and Wyke. Free nerve endings were the predominant sensory ending (P < 0.001). Ruffini and Golgi-like endings were rarely found and no Pacini corpuscles were seen. Significantly more free nerve endings (P < 0.001) and blood vessels (P = 0.01) were observed in the subtalar joint capsule than in the superficial part of the fat pad at the IER. The deep part of the fat pad at the IER had significantly more blood vessels than the superficial part of the fat pad at the IER (P = 0.012). Significantly more blood vessels than free nerve endings were seen in all three groups (P < 0.001). No significant differences in distribution were seen in terms of right or left side, except for free nerve endings in the superficial part of the fat pad at the IER (P = 0.003). A greater number of free nerve endings correlated with a greater number of blood vessels. The presence of sensory nerve endings between individual fat cells supports the hypothesis that the fat pad has a proprioceptive role monitoring changes and that it is a source of pain in sinus tarsi syndrome due to the abundance of free nerve endings. PMID:24472004

Sensory handedness is not reflected in cortical responses after basic nerve stimulation: a MEG study.

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Chen, Andrew C N; Theuvenet, Peter J; de Munck, Jan C; Peters, Maria J; van Ree, Jan M; Lopes da Silva, Fernando L

2012-04-01

Motor dominance is well established, but sensory dominance is much less clear. We therefore studied the cortical evoked magnetic fields using magnetoencephalography (MEG) in a group of 20 healthy right handed subjects in order to examine whether standard electrical stimulation of the median and ulnar nerve demonstrated sensory lateralization. The global field power (GFP) curves, as an indication of cortical activation, did not depict sensory lateralization to the dominant left hemisphere. Comparison of the M20, M30, and M70 peak latencies and GFP values exhibited no statistical differences between the hemispheres, indicating no sensory hemispherical dominance at these latencies for each nerve. Field maps at these latencies presented a first and second polarity reversal for both median and ulnar stimulation. Spatial dipole position parameters did not reveal statistical left-right differences at the M20, M30 and M70 peaks for both nerves. Neither did the dipolar strengths at M20, M30 and M70 show a statistical left-right difference for both nerves. Finally, the Laterality Indices of the M20, M30 and M70 strengths did not indicate complete lateralization to one of the hemispheres. After electrical median and ulnar nerve stimulation no evidence was found for sensory hand dominance in brain responses of either hand, as measured by MEG. The results can provide a new assessment of patients with sensory dysfunctions or perceptual distortion when sensory dominance occurs way beyond the estimated norm.

Sensory nerves are frequently involved in the spectrum of fisher syndrome.

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Shahrizaila, Nortina; Goh, Khean J; Kokubun, Norito; Tan, Ai H; Tan, Cheng Y; Yuki, Nobuhiro

2014-04-01

Differing patterns of neurophysiological abnormalities have been reported in patients with Fisher syndrome. Fisher syndrome is rare, and few series have incorporated prospective serial studies to define the natural history of nerve conduction studies in Guillain-Barré syndrome. In an ongoing prospective study of Guillain-Barré syndrome patients, patients who presented with Fisher syndrome and its spectrum of illness were assessed through serial neurological examinations, nerve conduction studies, and serological testing of IgG against gangliosides and ganglioside complexes. Of the 36 Guillain-Barré syndrome patients identified within 2 years, 17 had features of Fisher syndrome. Serial nerve conduction studies detected significant abnormalities in sensory nerve action potential amplitude in 94% of patients associated with 2 patterns of recovery-non-demyelinating reversible distal conduction failure and axonal regeneration. Similar changes were seen in motor nerves of 5 patients. Patients with the Fisher syndrome spectrum of illness have significant sensory involvement, which may only be evident with serial neurophysiological studies. Copyright © 2013 Wiley Periodicals, Inc.

Comparison of skin sensory thresholds using pre-programmed or single-frequency transcutaneous electrical nerve stimulation.

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Kang, Jong Ho

2015-12-01

[Purpose] The purpose of the present study was to compare the sensory thresholds of healthy subjects using pre-programmed or single-frequency transcutaneous electrical nerve stimulation. [Subjects] Ninety healthy adult subjects were randomly assigned to pre-programmed or single-frequency stimulation groups, each consisting of 45 participants. [Methods] Sensory thresholds were measured in the participants' forearms using von Frey filaments before and after pre-programmed or single-frequency transcutaneous electrical nerve stimulation, and the result in values were analyzed. [Results] Significant increases in sensory threshold after stimulation were observed in both groups. However, there were no significant differences between the two groups in sensory thresholds after stimulation or in the magnitude of threshold increases following stimulation. [Conclusion] Our results show that there are no differences between sensory threshold increases induced by pre-programmed and single-frequency transcutaneous electrical nerve stimulation.

Peripheral injury of pelvic visceral sensory nerves alters GFRa (GDNF family receptor alpha localization in sensory and autonomic pathways of the sacral spinal cord

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Shelley Lynne Forrest

2015-04-01

Full Text Available GDNF (glial cell line-derived neurotrophic factor, neurturin and artemin use their co-receptors (GFRα1, GFRα2 and GFRα3, respectively and the tyrosine kinase Ret for downstream signalling. In rodent dorsal root ganglia (DRG most of the unmyelinated and some myelinated sensory afferents express at least one GFRα. The adult function of these receptors is not completely elucidated but their activity after peripheral nerve injury can facilitate peripheral and central axonal regeneration, recovery of sensation, and sensory hypersensitivity that contributes to pain. Our previous immunohistochemical studies of spinal cord and sciatic nerve injuries in adult rodents have identified characteristic changes in GFRα1, GFRα2 or GFRα3 in central spinal cord axons of sensory neurons located in dorsal root ganglia. Here we extend and contrast this analysis by studying injuries of the pelvic and hypogastric nerves that contain the majority of sensory axons projecting to the pelvic viscera (e.g., bladder and lower bowel. At 7 d, we detected some effects of pelvic but not hypogastric nerve transection on the ipsilateral spinal cord. In sacral (L6-S1 cord ipsilateral to nerve injury, GFRα1-immunoreactivity (IR was increased in medial dorsal horn and CGRP-IR was decreased in lateral dorsal horn. Pelvic nerve injury also upregulated GFRα1- and GFRα3-IR terminals and GFRα1-IR neuronal cell bodies in the sacral parasympathetic nucleus that provides the spinal parasympathetic preganglionic output to the pelvic nerve. This evidence suggests peripheral axotomy has different effects on somatic and visceral sensory input to the spinal cord, and identifies sensory-autonomic interactions as a possible site of post-injury regulation.

Sensory nerve cross-anastomosis and electrical muscle stimulation synergistically enhance functional recovery of chronically denervated muscle.

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Willand, Michael P; Holmes, Michael; Bain, James R; de Bruin, Hubert; Fahnestock, Margaret

2014-11-01

Long-term muscle denervation leads to severe and irreversible atrophy coupled with loss of force and motor function. These factors contribute to poor functional recovery following delayed reinnervation. The authors' previous work demonstrated that temporarily suturing a sensory nerve to the distal motor stump (called sensory protection) significantly reduces muscle atrophy and improves function following reinnervation. The authors have also shown that 1 month of electrical stimulation of denervated muscle significantly improves function and reduces atrophy. In this study, the authors tested whether a combination of sensory protection and electrical stimulation would enhance functional recovery more than either treatment alone. Rat gastrocnemius muscles were denervated by cutting the tibial nerve. The peroneal nerve was then sutured to the distal tibial stump following 3 months of treatment (i.e., electrical stimulation, sensory protection, or both). Three months after peroneal repair, functional and histologic measurements were taken. All treatment groups had significantly higher muscle weight (pstimulation or sensory protection alone. The combined treatment also produced motor unit counts significantly greater than sensory protection alone (p<0.05). The combination treatment synergistically reduces atrophy and improves reinnervation and functional measures following delayed nerve repair, suggesting that these approaches work through different mechanisms. The authors' research supports the clinical use of both modalities together following peripheral nerve injury.

Morphology and nanomechanics of sensory neurons growth cones following peripheral nerve injury.

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Marta Martin

Full Text Available A prior peripheral nerve injury in vivo, promotes a rapid elongated mode of sensory neurons neurite regrowth in vitro. This in vitro model of conditioned axotomy allows analysis of the cellular and molecular mechanisms leading to an improved neurite re-growth. Our differential interference contrast microscopy and immunocytochemistry results show that conditioned axotomy, induced by sciatic nerve injury, did not increase somatic size of adult lumbar sensory neurons from mice dorsal root ganglia sensory neurons but promoted the appearance of larger neurites and growth cones. Using atomic force microscopy on live neurons, we investigated whether membrane mechanical properties of growth cones of axotomized neurons were modified following sciatic nerve injury. Our data revealed that neurons having a regenerative growth were characterized by softer growth cones, compared to control neurons. The increase of the growth cone membrane elasticity suggests a modification in the ratio and the inner framework of the main structural proteins.

Sensory nerve endings in the penis in green monkey (Cercopithecus aethiops sabaeus).

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Malinovský, L; Sommerová, J

1977-01-01

The authors examined the sensory innervation of the skin in the penis in green monkey in four adult individuals both in the light and in the elctron microscope. They found 3 kings of nerve endings. The free nerve endings were the most frequently occurring kind of nerve endings in the superficial layers of the corium--altogether 6,444 in number. The second kind of sensory nerve endings is represented by the glomerular endings out of which 96 per cent were found in the papillae. The typical Meissner's endings were observed in the light microscopy only rarely. Deeper in the corium the authors also found single simple sensory corpuscles and Pacinian corpuscles. Studying the ultrastructure the authors found in the papillae of the corium 4 types of glomerular endings: quite simple glomerular endings with irregularly arranged Schwann cells, larger and more complicated glomerular endings having a thicker capsule, endings with lamellar system around the terminals and typical Meissner's endings. In the epidermis the authors observed naked axons which passed in the spaces among the epidermal cells. They contained an accumulation of mitochondria. In the basal cell layer of the epidermis there was a small amount of Langerhans cells.

Palm to Finger Ulnar Sensory Nerve Conduction.

Science.gov (United States)

Davidowich, Eduardo; Nascimento, Osvaldo J M; Orsini, Marco; Pupe, Camila; Pessoa, Bruno; Bittar, Caroline; Pires, Karina Lebeis; Bruno, Carlos; Coutinho, Bruno Mattos; de Souza, Olivia Gameiro; Ribeiro, Pedro; Velasques, Bruna; Bittencourt, Juliana; Teixeira, Silmar; Bastos, Victor Hugo

2015-12-29

Ulnar neuropathy at the wrist (UNW) is rare, and always challenging to localize. To increase the sensitivity and specificity of the diagnosis of UNW many authors advocate the stimulation of the ulnar nerve (UN) in the segment of the wrist and palm. The focus of this paper is to present a modified and simplified technique of sensory nerve conduction (SNC) of the UN in the wrist and palm segments and demonstrate the validity of this technique in the study of five cases of type III UNW. The SNC of UN was performed antidromically with fifth finger ring recording electrodes. The UN was stimulated 14 cm proximal to the active electrode (the standard way) and 7 cm proximal to the active electrode. The normal data from amplitude and conduction velocity (CV) ratios between the palm to finger and wrist to finger segments were obtained. Normal amplitude ratio was 1.4 to 0.76. Normal CV ratio was 0.8 to 1.23.We found evidences of abnormal SNAP amplitude ratio or substantial slowing of UN sensory fibers across the wrist in 5 of the 5 patients with electrophysiological-definite type III UNW.

Palm to finger ulnar sensory nerve conduction

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Eduardo Davidowich

2015-12-01

Full Text Available Ulnar neuropathy at the wrist (UNW is rare, and always challenging to localize. To increase the sensitivity and specificity of the diagnosis of UNW many authors advocate the stimulation of the ulnar nerve (UN in the segment of the wrist and palm. The focus of this paper is to present a modified and simplified technique of sensory nerve conduction (SNC of the UN in the wrist and palm segments and demonstrate the validity of this technique in the study of five cases of type III UNW. The SNC of UN was performed antidromically with fifth finger ring recording electrodes. The UN was stimulated 14 cm proximal to the active electrode (the standard way and 7 cm proximal to the active electrode. The normal data from amplitude and conduction velocity (CV ratios between the palm to finger and wrist to finger segments were obtained. Normal amplitude ratio was 1.4 to 0.76. Normal CV ratio was 0.8 to 1.23.We found evidences of abnormal SNAP amplitude ratio or substantial slowing of UN sensory fibers across the wrist in 5 of the 5 patients with electrophysiological-definite type III UNW.

Reliability, reference values and predictor variables of the ulnar sensory nerve in disease free adults.

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Ruediger, T M; Allison, S C; Moore, J M; Wainner, R S

2014-09-01

The purposes of this descriptive and exploratory study were to examine electrophysiological measures of ulnar sensory nerve function in disease free adults to determine reliability, determine reference values computed with appropriate statistical methods, and examine predictive ability of anthropometric variables. Antidromic sensory nerve conduction studies of the ulnar nerve using surface electrodes were performed on 100 volunteers. Reference values were computed from optimally transformed data. Reliability was computed from 30 subjects. Multiple linear regression models were constructed from four predictor variables. Reliability was greater than 0.85 for all paired measures. Responses were elicited in all subjects; reference values for sensory nerve action potential (SNAP) amplitude from above elbow stimulation are 3.3 μV and decrement across-elbow less than 46%. No single predictor variable accounted for more than 15% of the variance in the response. Electrophysiologic measures of the ulnar sensory nerve are reliable. Absent SNAP responses are inconsistent with disease free individuals. Reference values recommended in this report are based on appropriate transformations of non-normally distributed data. No strong statistical model of prediction could be derived from the limited set of predictor variables. Reliability analyses combined with relatively low level of measurement error suggest that ulnar sensory reference values may be used with confidence. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Proximally evoked soleus H-reflex to S1 nerve root stimulation in sensory neuronopathies (ganglionopathies).

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Zhu, Dong-Qing; Zhu, Yu; Qiao, Kai; Zheng, Chao-Jun; Bradley, Scott; Weber, Robert; Chen, Xiang-Jun

2013-11-01

Sensory neuronopathy (SNN) mimics distal sensory axonopathy. The conventional H-reflex elicited by tibial nerve stimulation (tibial H-reflex) is usually abnormal in both conditions. We evaluated the proximally evoked soleus H-reflex in response to S1 nerve root stimulation (S1 foramen H-reflex) in SNN. Eleven patients with SNN and 6 with distal sensory axonopathy were studied. Tibial and S1 foramen H-reflexes were performed bilaterally in each patient. Tibial and S1 foramen H-reflexes were absent bilaterally in all patients with SNN. In the patients with distal sensory axonopathy, tibial H-reflexes were absent in 4 and demonstrated prolonged latencies in 2, but S1 foramen H-reflexes were normal. Characteristic absence of the H-reflex after both proximal and distal stimulation reflects primary loss of dorsal root ganglion (DRG) neurons and the distinct non-length-dependent impairment of sensory nerve fibers in SNN. Copyright © 2013 Wiley Periodicals, Inc.

Pulmonary Stress Induced by Hyperthermia: Role of Airway Sensory Nerves

Science.gov (United States)

2016-01-01

Myers AC, Kajekar R, Undem BJ. Allergic inflammation-induced neuropeptide production in rapidly adapting afferent nerves in guinea pig airways. Am J...induced neuro- peptide production in rapidly adapting afferent nerves in guinea pig airways. Am. J. Physiol. Lung Cell. Mol. Physiol. 282, L775–L781...co-localization of transient receptor po- tential vanilloid (trpv)1 and sensory neuropeptides in the guinea - pig respiratory system. Neuroscience

Patients' views on early sensory relearning following nerve repair-a Q-methodology study.

Science.gov (United States)

Vikström, Pernilla; Carlsson, Ingela; Rosén, Birgitta; Björkman, Anders

2017-09-26

Descriptive study. Early sensory relearning where the dynamic capacity of the brain is used has been shown to improve sensory outcome after nerve repair. However, no previous studies have examined how patients experience early sensory relearning. To describe patient's views on early sensory relearning. Statements' scores were analyzed by factor analysis. Thirty-seven consecutive adult patients with median and/or ulnar nerve repair who completed early sensory relearning were included. Three factors were identified, explaining 45% of the variance: (1) "Believe sensory relearning is meaningful, manage to get an illusion of touch and complete the sensory relearning"; (2) "Do not get an illusion of touch easily and need support in their sensory relearning" (3) "Are not motivated, manage to get an illusion of touch but do not complete sensory relearning". Many patients succeed in implementing their sensory relearning. However, a substantial part of the patient population need more support, have difficulties to create illusion of touch, and lack motivation to complete the sensory relearning. To enhance motivation and meaningfulness by relating the training clearly to everyday occupations and to the patient's life situation is a suggested way to proceed. The three unique factors indicate motivation and sense of meaningfulness as key components which should be taken into consideration in developing programs for person-centered early sensory relearning. 3. Copyright © 2017 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

Sonography-guided recording for superficial peroneal sensory nerve conduction study.

Science.gov (United States)

Kim, Ki Hoon; Park, Byung Kyu; Kim, Dong Hwee; Kim, Yuntae

2018-04-01

We sought to establish the optimal recording position for antidromic conduction of the superficial peroneal nerve (SPN) by using ultrasonography (USG). The sensory nerve action potentials (SNAPs) of the intermediate dorsal cutaneous nerve (IDCN) and medial dorsal cutaneous nerve (MDCN) in 64 limbs of 32 healthy participants were recorded (nerve conduction study [NCS]-1). Both nerves were identified by using USG, and the SNAPs were obtained from the USG-guided repositioned electrodes (NCS-2). The IDCN and MDCN were located at 29.3% ± 5.1% and 43.9% ± 4.9% of the intermalleolar distance from the lateral malleolus, respectively. Significantly greater amplitude was shown for SNAPs of both nerves in NCS-2 versus NCS-1. The optimal recording position is likely to be lateral, one-third from the lateral malleolus for the IDCN, and just lateral to the midpoint of the intermalleolar line for the MDCN. When the SPN response is unexpectedly attenuated, USG-guided repositioning of the electrodes should be considered. Muscle Nerve 57: 628-633, 2018. © 2017 Wiley Periodicals, Inc.

Degeneration and regeneration of motor and sensory nerves: a stereological study of crush lesions in rat facial and mental nerves

DEFF Research Database (Denmark)

Barghash, Ziad; Larsen, Jytte Overgaard; Al-Bishri, Awad

2013-01-01

The aim of this study was to evaluate the degeneration and regeneration of a sensory nerve and a motor nerve at the histological level after a crush injury. Twenty-five female Wistar rats had their mental nerve and the buccal branch of their facial nerve compressed unilaterally against a glass rod...... for 30 s. Specimens of the compressed nerves and the corresponding control nerves were dissected at 3, 7, and 19 days after surgery. Nerve cross-sections were stained with osmium tetroxide and toluidine blue and analysed using two-dimensional stereology. We found differences between the two nerves both...... in the normal anatomy and in the regenerative pattern. The mental nerve had a larger cross-sectional area including all tissue components. The mental nerve had a larger volume fraction of myelinated axons and a correspondingly smaller volume fraction of endoneurium. No differences were observed...

Inhibiting Heat-Shock Protein 90 Reverses Sensory Hypoalgesia in Diabetic Mice

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Michael J Urban

2010-07-01

Full Text Available Increasing the expression of Hsp70 (heat-shock protein 70 can inhibit sensory neuron degeneration after axotomy. Since the onset of DPN (diabetic peripheral neuropathy is associated with the gradual decline of sensory neuron function, we evaluated whether increasing Hsp70 was sufficient to improve several indices of neuronal function. Hsp90 is the master regulator of the heat-shock response and its inhibition can up-regulate Hsp70. KU-32 (N-{7-[(2R, 3R, 4S, 5R-3, 4-dihydroxy-5-methoxy-6, 6-dimethyl-tetrahydro-2H-pyran-2-yloxy]-8-methyl-2-oxo-2H-chromen-3-yl}acetamide was developed as a novel, novobiocin-based, C-terminal inhibitor of Hsp90 whose ability to increase Hsp70 expression is linked to the presence of an acetamide substitution of the prenylated benzamide moiety of novobiocin. KU-32 protected against glucose-induced death of embryonic DRG (dorsal root ganglia neurons cultured for 3 days in vitro. Similarly, KU-32 significantly decreased neuregulin 1-induced degeneration of myelinated Schwann cell DRG neuron co-cultures prepared from WT (wild-type mice. This protection was lost if the co-cultures were prepared from Hsp70.1 and Hsp70.3 KO (knockout mice. KU-32 is readily bioavailable and was administered once a week for 6 weeks at a dose of 20 mg/kg to WT and Hsp70 KO mice that had been rendered diabetic with streptozotocin for 12 weeks. After 12 weeks of diabetes, both WT and Hsp70 KO mice developed deficits in NCV (nerve conduction velocity and a sensory hypoalgesia. Although KU-32 did not improve glucose levels, HbA1c (glycated haemoglobin or insulin levels, it reversed the NCV and sensory deficits in WT but not Hsp70 KO mice. These studies provide the first evidence that targeting molecular chaperones reverses the sensory hypoalgesia associated with DPN.

Modelled temperature-dependent excitability behaviour of a generalised human peripheral sensory nerve fibre.

Science.gov (United States)

Smit, Jacoba E; Hanekom, Tania; Hanekom, Johan J

2009-08-01

The objective of this study was to determine if a recently developed human Ranvier node model, which is based on a modified version of the Hodgkin-Huxley model, could predict the excitability behaviour in human peripheral sensory nerve fibres with diameters ranging from 5.0 to 15.0 microm. The Ranvier node model was extended to include a persistent sodium current and was incorporated into a generalised single cable nerve fibre model. Parameter temperature dependence was included. All calculations were performed in Matlab. Sensory nerve fibre excitability behaviour characteristics predicted by the new nerve fibre model at different temperatures and fibre diameters compared well with measured data. Absolute refractory periods deviated from measured data, while relative refractory periods were similar to measured data. Conduction velocities showed both fibre diameter and temperature dependence and were underestimated in fibres thinner than 12.5 microm. Calculated strength-duration time constants ranged from 128.5 to 183.0 micros at 37 degrees C over the studied nerve fibre diameter range, with chronaxie times about 30% shorter than strength-duration time constants. Chronaxie times exhibited temperature dependence, with values overestimated by a factor 5 at temperatures lower than body temperature. Possible explanations include the deviated absolute refractory period trend and inclusion of a nodal strangulation relationship.

Methods for assessing diabetic polyneuropathy : validity and reproducibility of the measurement of sensory symptom severity and nerve function tests

NARCIS (Netherlands)

Valk, G D; Grootenhuis, P A; van Eijk, J T; Bouter, L M; Bertelsmann, F W

The usefulness of sensory symptoms in the assessment of diabetic polyneuropathy is unclear. In the present study, we studied the hypothesis that pain is associated with small nerve fibre function, and that sensory alteration is associated with large nerve fibre function. In addition, we assessed the

A urodynamic study of surface neuromodulation versus sham in detrusor instability and sensory urgency.

Science.gov (United States)

Bower, W F; Moore, K H; Adams, R D; Shepherd, R

1998-12-01

We studied the effect of surface neuromodulation on cystometric pressure and volume parameters in women with detrusor instability or sensory urgency. Electrical current was delivered to the suprapubic region and third sacral foramina via a transcutaneous electrical nerve stimulator with sham neuromodulation control. A consecutive series of women with proved detrusor instability or sensory urgency were randomized to 3 surface neuromodulation groups. Volume and pressure parameters were the main outcomes of transcutaneous electrical nerve stimulation applied during second cystometric fill. Sham transcutaneous electrical nerve stimulation did not alter the outcome measures. However, neuromodulation delivered across the suprapubic and sacral skin effected a reduction in mean maximum height of detrusor contraction. A current which inhibits motor activity was not superior to that which inhibits sensory perception in reducing detrusor pressure. Response in sensory urgency was poor. Results from our sham controlled study suggest that short-term surface neuromodulation via transcutaneous electrical nerve stimulation may have a role in the treatment of detrusor instability. Future studies must examine the clinical effect of long-term surface neuromodulation.

Sensory nerve degeneration in a mouse model mimicking early manifestations of familial amyloid polyneuropathy due to transthyretin Ala97Ser.

Science.gov (United States)

Kan, H-W; Chiang, H; Lin, W-M; Yu, I-S; Lin, S-W; Hsieh, S-T

2018-02-08

Sensory nerve degeneration and consequent abnormal sensations are the earliest and most prevalent manifestations of familial amyloid polyneuropathy (FAP) due to amyloidogenic transthyretin (TTR). FAP is a relentlessly progressive degenerative disease of the peripheral nervous system. However, there is a lack of mouse models to replicate the early neuropathic manifestations of FAP. We established human TTR knock-in mice by replacing one allele of the mouse Ttr locus with human wild-type TTR (hTTR wt ) or human TTR with the A97S mutation (hTTR A97S ). Given the late onset of neuropathic manifestations in A97S-FAP, we investigated nerve pathology, physiology, and behavioural tests in these mice at two age points: the adult group (8 - 56 weeks) and the ageing group (> 104 weeks). In the adult group, nerve profiles, neurophysiology and behaviour were similar between hTTR wt and hTTR A97S mice. By contrast, ageing hTTR A97S mice showed small fibre neuropathy with decreased intraepidermal nerve fibre density and behavioural signs of mechanical allodynia. Furthermore, significant reductions in sural nerve myelinated nerve fibre density and sensory nerve action potential amplitudes in these mice indicated degeneration of large sensory fibres. The unaffected motor nerve physiology replicated the early symptoms of FAP patients, that is, sensory nerves were more vulnerable to mutant TTR than motor nerves. These results demonstrate that the hTTR A97S mouse model develops sensory nerve pathology and corresponding physiology mimicking A97S-FAP and provides a platform to develop new therapies for the early stage of A97S-FAP. © 2018 British Neuropathological Society.

Regeneration of unmyelinated and myelinated sensory nerve fibres studied by a retrograde tracer method

DEFF Research Database (Denmark)

Lozeron, Pierre; Krarup, Christian; Schmalbruch, Henning

2004-01-01

cells that had been labelled, i.e., that had regenerated axons towards or beyond the injection site, were counted in serial sections. Large and small neurons with presumably myelinated and unmyelinated axons, respectively, were classified by immunostaining for neurofilaments. The axonal growth rate......Regeneration of myelinated and unmyelinated sensory nerve fibres after a crush lesion of the rat sciatic nerve was investigated by means of retrograde labelling. The advantage of this method is that the degree of regeneration is estimated on the basis of sensory somata rather than the number...... of axons. Axonal counts do not reflect the number of regenerated neurons because of axonal branching and because myelinated axons form unmyelinated sprouts. Two days to 10 weeks after crushing, the distal sural or peroneal nerves were cut and exposed to fluoro-dextran. Large and small dorsal root ganglion...

Compound sensory action potential in normal and pathological human nerves

DEFF Research Database (Denmark)

Krarup, Christian

2004-01-01

The compound sensory nerve action potential (SNAP) is the result of phase summation and cancellation of single fiber potentials (SFAPs) with amplitudes that depend on fiber diameter, and the amplitude and shape of the SNAP is determined by the distribution of fiber diameters. Conduction velocitie...... effort and attention to theory and practical detail that may be time consuming....

Odor-evoked inhibition of olfactory sensory neurons drives olfactory perception in Drosophila.

Science.gov (United States)

Cao, Li-Hui; Yang, Dong; Wu, Wei; Zeng, Xiankun; Jing, Bi-Yang; Li, Meng-Tong; Qin, Shanshan; Tang, Chao; Tu, Yuhai; Luo, Dong-Gen

2017-11-07

Inhibitory response occurs throughout the nervous system, including the peripheral olfactory system. While odor-evoked excitation in peripheral olfactory cells is known to encode odor information, the molecular mechanism and functional roles of odor-evoked inhibition remain largely unknown. Here, we examined Drosophila olfactory sensory neurons and found that inhibitory odors triggered outward receptor currents by reducing the constitutive activities of odorant receptors, inhibiting the basal spike firing in olfactory sensory neurons. Remarkably, this odor-evoked inhibition of olfactory sensory neurons elicited by itself a full range of olfactory behaviors from attraction to avoidance, as did odor-evoked olfactory sensory neuron excitation. These results indicated that peripheral inhibition is comparable to excitation in encoding sensory signals rather than merely regulating excitation. Furthermore, we demonstrated that a bidirectional code with both odor-evoked inhibition and excitation in single olfactory sensory neurons increases the odor-coding capacity, providing a means of efficient sensory encoding.

Apoptosis-inducing effect of selective sensory or motor nerve injury on skeletal muscle atrophy

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Lei ZHAO

2011-09-01

Full Text Available Objective To explore the apoptosis-inducing effect of selective sensory or motor nerve injury on skeletal muscle atrophy.Methods Thirty healthy adult SD rats were randomly divided into three groups,namely,ventral root transection group(VRT group,received left L4-L6 ventral rhizotomy,dorsal root transection group(DRT group,received left L4-L6 dorsal rhizotomy,and sciatic nerve transection group(SNT group,received left sciatic nerve transection.Each group comprised 10 SD rats.The bilateral gastrocnemius was harvested 10 weeks after operation to observe the apoptosis and Fas/FasL expression of the skeletal muscle cells through fluorescent labeling,transmission electron microscopy,and immunohistochemistry.Result Ten weeks after the denervation,apoptosis-related changes,especially obvious changes of the nuclear apoptotic morphology,were observed in the skeletal muscle cells.The aggregation degree of the nucleus and the expression of Fas/FasL increased in the following order: DRT group,VRT group,and SNT group.No apoptotic body,but early apoptotic morphology,was found in the denervated gastrocnemius through transmission electron microscopy.Conclusions The effect of motor nerve injury on skeletal muscle atrophy is more serious than that of sensory nerve injury.The rebuilding of motor nerves should be preferentially considered in the clinical treatment of muscle atrophy induced by denervation.

Sensory action potentials of the maxillary nerve: a methodologic study with clinical implications

DEFF Research Database (Denmark)

Thygesen, Torben; Baad-Hansen, Lene; Svensson, Peter

2009-01-01

PURPOSE: Recently, recording of sensory nerve action potentials (SNAPs) of the inferior alveolar nerve (IAN) was described and is used as a diagnostic test of traumatic neuropathic trigeminal disorders. The technique is limited to IAN damage; therefore, we adapted the technique to the maxillary...... nerve, which is also frequently injured by either trauma or orthognathic surgery. PATIENTS AND METHODS: Fourteen healthy volunteers participated in this methodologic study in which the infraorbital nerve (ION) was stimulated with 2 needle electrodes. The SNAPs were recorded from the maxillary nerve...... difference. Repeated tests within a session test demonstrated no significant differences in the latency data (ANOVA: P= .225) or amplitude data (ANOVA: P= .44). Stimulus-response curves indicated that the SNAPs saturated at 5.1+/-4.4 mA stimulus intensity. In 1 subject, stimulation of the mental nerve...

Sensory nerve conduction in the caudal nerves of rats with diabetes Condução nervosa sensorial no nervo caudal de ratos com diabetes experimental

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Celina Cordeiro de Carvalho

2011-04-01

Full Text Available PURPOSE: To investigate sensory nerve conduction of the caudal nerve in normal and diabetic rats. METHODS: Diabetes was induced in twenty 8-weeks old Wistar male rats. Twenty normal rats served as controls. Caudal nerve conduction studies were made before diabetes induction and the end of each week for six consecutive weeks. The caudal nerve was stimulated distally and nerve potentials were recorded proximally on the animal's tail using common "alligator" clips as surface electrodes. RESULTS: After induction, nerve conduction velocities (NCV increased slower in the diabetic than in the control group. Sensory nerve action potentials (SNAP conduction velocities increased slower in the diabetic than in the control group (slope of regression line: 0.5 vs 1.3m/s per week; NCV in the 15th week = 39±3m/s vs 44±4m/s. Tukey's tests showed differences between groups at the 11th, 13th and 15th weeks old. From the 10th week on, SNAP amplitudes increased faster in the diabetic than in the control group (slopes of the regression line: 10 vs 8µV per week; SNAP amplitudes in the 15th week: 107±23µV vs 85±13µV. Differences at the 12th, 13th and 15th weeks were significant. CONCLUSION: In diabetic rats nerve conduction velocities were slower whereas amplitudes were larger than in normal rats.OBJETIVO: Investigar a condução nervosa sensorial do nervo caudal em ratos normais e diabéticos. MÉTODOS: O diabetes foi induzido em vinte ratos Wistar com idade de oito semanas. Vinte ratos serviram como controle. Os estudos da condução do nervo caudal foram feitos antes da indução do diabetes e ao final de cada semana, durante seis semanas consecutivas. O nervo caudal foi estimulado distalmente e potenciais foram registrados proximalmente na cauda do animal, usando clipes comuns "jacaré" como eletrodos de superfície. RESULTADOS: Após a indução, a velocidade de condução nervosa (VCN aumentou mais lentamente no grupo diabético que no controle

Sensation, mechanoreceptor, and nerve fiber function after nerve regeneration

DEFF Research Database (Denmark)

Krarup, Christian; Rosén, Birgitta; Boeckstyns, Michel

2017-01-01

Objective: Sensation is essential for recovery after peripheral nerve injury. However, the relationship between sensory modalities and function of regenerated fibers is uncertain. We have investigated the relationships between touch threshold, tactile gnosis, and mechanoreceptor and sensory fiber...... function after nerve regeneration. Methods: Twenty-one median or ulnar nerve lesions were repaired by a collagen nerve conduit or direct suture. Quantitative sensory hand function and sensory conduction studies by near-nerve technique, including tactile stimulation of mechanoreceptors, were followed for 2...... years, and results were compared to noninjured hands. Results: At both repair methods, touch thresholds at the finger tips recovered to 81 ± 3% and tactile gnosis only to 20 ± 4% (p nerve action potentials (SNAPs) remained dispersed and areas recovered to 23 ± 2...

[Age-related changes of sensory peripheral nerve system in healthy subjects.

Science.gov (United States)

Voitenkov, V B; Ekusheva, E V; Komancev, V N; Skripchenko, N V; Grigoryev, S G; Klimkin, A V; Aksenova, A I

2017-01-01

Our aim was to present and evaluate age-related changes of peripheral nerves of limbs on a huge population of healthy subjects of different ages. In 2009-2016 subjects aged from 1months to 90 years were studied by nerve conduction velocity studies (NCV). Data of those confirmed healthy was included in our study. In total there were 372 healthy subjects. NCV for nn. Medianus et Ulnaris was registered, with NCV and amplitude of compound sensory action potential (CSAP) being analyzed. There were significant differences on both these parameters between different age groups. Since the childhood the improvement of conduction (which was reflected in rising of CSAP amplitudes and NCV quickening) was registered; from 40-50 years steady decline of both these parameters were observed in both nerves. Conduction studies of peripheral nerves may be implemented in gerontology for early detection of neurophysiology patterns reflecting physiological aging. Also our results may be implemented for accelerated aging detection.

Degeneration and regeneration of motor and sensory nerves: a stereological study of crush lesions in rat facial and mental nerves.

Science.gov (United States)

Barghash, Z; Larsen, J O; Al-Bishri, A; Kahnberg, K-E

2013-12-01

The aim of this study was to evaluate the degeneration and regeneration of a sensory nerve and a motor nerve at the histological level after a crush injury. Twenty-five female Wistar rats had their mental nerve and the buccal branch of their facial nerve compressed unilaterally against a glass rod for 30s. Specimens of the compressed nerves and the corresponding control nerves were dissected at 3, 7, and 19 days after surgery. Nerve cross-sections were stained with osmium tetroxide and toluidine blue and analysed using two-dimensional stereology. We found differences between the two nerves both in the normal anatomy and in the regenerative pattern. The mental nerve had a larger cross-sectional area including all tissue components. The mental nerve had a larger volume fraction of myelinated axons and a correspondingly smaller volume fraction of endoneurium. No differences were observed in the degenerative pattern; however, at day 19 the buccal branch had regenerated to the normal number of axons, whereas the mental nerve had only regained 50% of the normal number of axons. We conclude that the regenerative process is faster and/or more complete in the facial nerve (motor function) than it is in the mental nerve (somatosensory function). Copyright © 2013 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Burning Mouth Syndrome and Other Oral Sensory Disorders: A Unifying Hypothesis

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Miriam Grushka

2003-01-01

Full Text Available Burning Mouth Syndrome (BMS is a sensory disorder which results in constant, bilateral burning pain of the tongue, lips, and other oral mucous membranes. Atypical odontalgia (AO is another sensory disorder, usually defined as a toothache-like pain for which no dental cause can be identified. Previous literature has suggested that AO is often associated with a concomitant temporomandibular disorder (TMD. This hypothesis paper explores the possibility that BMS, AO and TMD can be related through hyperactivity of both the sensory and motor components of the trigeminal nerve following loss of central inhibition as a result of taste damage in the chorda tympani and/or the glossopharyngeal nerves.

Long-Standing Motor and Sensory Recovery following Acute Fibrin Sealant Based Neonatal Sciatic Nerve Repair

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Natalia Perussi Biscola

2016-01-01

Full Text Available Brachial plexus lesion results in loss of motor and sensory function, being more harmful in the neonate. Therefore, this study evaluated neuroprotection and regeneration after neonatal peripheral nerve coaptation with fibrin sealant. Thus, P2 neonatal Lewis rats were divided into three groups: AX: sciatic nerve axotomy (SNA without treatment; AX+FS: SNA followed by end-to-end coaptation with fibrin sealant derived from snake venom; AX+CFS: SNA followed by end-to-end coaptation with commercial fibrin sealant. Results were analyzed 4, 8, and 12 weeks after lesion. Astrogliosis, microglial reaction, and synapse preservation were evaluated by immunohistochemistry. Neuronal survival, axonal regeneration, and ultrastructural changes at ventral spinal cord were also investigated. Sensory-motor recovery was behaviorally studied. Coaptation preserved synaptic covering on lesioned motoneurons and led to neuronal survival. Reactive gliosis and microglial reaction decreased in the same groups (AX+FS, AX+CFS at 4 weeks. Regarding axonal regeneration, coaptation allowed recovery of greater number of myelinated fibers, with improved morphometric parameters. Preservation of inhibitory synaptic terminals was accompanied by significant improvement in the motor as well as in the nociceptive recovery. Overall, the present data suggest that acute repair of neonatal peripheral nerves with fibrin sealant results in neuroprotection and regeneration of motor and sensory axons.

Modelled temperature-dependent excitability behaviour of a generalised human peripheral sensory nerve fibre

CSIR Research Space (South Africa)

Smit, Jacoba E

2009-09-01

Full Text Available The objective of this study was to determine if a recently developed human Ranvier node model, which is based on a modified version of the Hodgkin-Huxley model, could predict the excitability behaviour in human peripheral sensory nerve fibres...

Effect of Selective Temporary Anaesthesia in Combination with Sensory Re-Education on Improvement of Hand Sensibility after Median and Ulnar Nerve Repair

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Roghayeh Hasan-Zadeh

2008-04-01

Full Text Available Objective: The results of sensory improvement from nerve repair in adult are often poor. To confirm with previous results and this hypothesis that forearm deafferentation would enhance the sensory outcome by increasing the cortical hand representation, this study is aimed to investigate the effect of repeated sessions of cutaneous forearm anaesthesia of the injured limb, in combination with sensory re-education on the sensory outcome in the hand after median or ulnar nerve repair. Materials & Methods: This experimental study was designed as a double-blind randomized clinical trial. 13 patients that they had been undergoing surgery of hand nerves repaire were selected probability and assigned to examination (n=6 and control (n=7 group. During a 2 week period, a topical anaesthetic cream (Lidocaine for examination group and a placebo for control group was applied repeatedly (twice a week for 1 hour onto the flexor aspect of the forearm of injured hand and combined with sensory re-education. Assessments of sensory function were performed prior to the experiment and after the fourth application of Lidocaine/placebo. For analysis of data, Wilcoxon singed rank and Mann - Whitney U-tests were used. Results: Perception of touch that was measured with SWMs, had been improved significantly in the Lidocaine group in comparison with placebo group (P=0/03. Conclusion: This finding suggests that forearm deafferentation of injured limb, in combination with sensory re-education, can enhance sensory reover after nerve repair.

Spinal Cord Excitability and Sprint Performance Are Enhanced by Sensory Stimulation During Cycling

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Gregory E. P. Pearcey

2017-12-01

Full Text Available Spinal cord excitability, as assessed by modulation of Hoffmann (H- reflexes, is reduced with fatiguing isometric contractions. Furthermore, spinal cord excitability is reduced during non-fatiguing arm and leg cycling. Presynaptic inhibition of Ia terminals is believed to contribute to this suppression of spinal cord excitability. Electrical stimulation to cutaneous nerves reduces Ia presynaptic inhibition, which facilitates spinal cord excitability, and this facilitation is present during arm cycling. Although it has been suggested that reducing presynaptic inhibition may prolong fatiguing contractions, it is unknown whether sensory stimulation can alter the effects of fatiguing exercise on performance or spinal cord excitability. Thus, the aim of this experiment was to determine if sensory stimulation can interfere with fatigue-related suppression of spinal cord excitability, and alter fatigue rates during cycling sprints. Thirteen participants randomly performed three experimental sessions that included: unloaded cycling with sensory stimulation (CONTROL + STIM, sprints with sensory stimulation (SPRINT + STIM and sprints without stimulation (SPRINT. Seven participants also performed a fourth session (CONTROL, which consisted of unloaded cycling. During SPRINT and SPRINT + STIM, participants performed seven, 10 s cycling sprints interleaved with 3 min rest. For CONTROL and CONTROL + STIM, participants performed unloaded cycling for ~30 min. During SPRINT + STIM and CONTROL + STIM, participants received patterned sensory stimulation to nerves of the right foot. H-reflexes and M-waves of the right soleus were evoked by stimulation of the tibial nerve at multiple time points throughout exercise. Sensory stimulation facilitated soleus H-reflexes during unloaded cycling, whereas sprints suppressed soleus H-reflexes. While receiving sensory stimulation, there was less suppression of soleus H-reflexes and slowed reduction in average power output

Spinal Cord Excitability and Sprint Performance Are Enhanced by Sensory Stimulation During Cycling.

Science.gov (United States)

Pearcey, Gregory E P; Noble, Steven A; Munro, Bridget; Zehr, E Paul

2017-01-01

Spinal cord excitability, as assessed by modulation of Hoffmann (H-) reflexes, is reduced with fatiguing isometric contractions. Furthermore, spinal cord excitability is reduced during non-fatiguing arm and leg cycling. Presynaptic inhibition of Ia terminals is believed to contribute to this suppression of spinal cord excitability. Electrical stimulation to cutaneous nerves reduces Ia presynaptic inhibition, which facilitates spinal cord excitability, and this facilitation is present during arm cycling. Although it has been suggested that reducing presynaptic inhibition may prolong fatiguing contractions, it is unknown whether sensory stimulation can alter the effects of fatiguing exercise on performance or spinal cord excitability. Thus, the aim of this experiment was to determine if sensory stimulation can interfere with fatigue-related suppression of spinal cord excitability, and alter fatigue rates during cycling sprints. Thirteen participants randomly performed three experimental sessions that included: unloaded cycling with sensory stimulation ( CONTROL + STIM ), sprints with sensory stimulation ( SPRINT + STIM ) and sprints without stimulation ( SPRINT ). Seven participants also performed a fourth session ( CONTROL ), which consisted of unloaded cycling. During SPRINT and SPRINT + STIM, participants performed seven, 10 s cycling sprints interleaved with 3 min rest. For CONTROL and CONTROL + STIM , participants performed unloaded cycling for ~30 min. During SPRINT + STIM and CONTROL + STIM , participants received patterned sensory stimulation to nerves of the right foot. H-reflexes and M-waves of the right soleus were evoked by stimulation of the tibial nerve at multiple time points throughout exercise. Sensory stimulation facilitated soleus H-reflexes during unloaded cycling, whereas sprints suppressed soleus H-reflexes. While receiving sensory stimulation, there was less suppression of soleus H-reflexes and slowed reduction in average power output, compared

Painful nerve injury decreases resting cytosolic calcium concentrations in sensory neurons of rats

NARCIS (Netherlands)

Fuchs, Andreas; Lirk, Philipp; Stucky, Cheryl; Abram, Stephen E.; Hogan, Quinn H.

2005-01-01

Neuropathic pain is difficult to treat and poorly understood at the cellular level. Although cytoplasmic calcium ([Ca]c) critically regulates neuronal function, the effects of peripheral nerve injury on resting sensory neuronal [Ca]c are unknown. Resting [Ca]c was determined by microfluorometry in

Good sensory recovery of the hand in brachial plexus surgery using the intercostobrachial nerve as the donor

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Luciano Foroni

Full Text Available ABSTRACT Objective: Restoration of the sensitivity to sensory stimuli in complete brachial plexus injury is very important. The objective of our study was to evaluate sensory recovery in brachial plexus surgery using the intercostobrachial nerve (ICBN as the donor. Methods: Eleven patients underwent sensory reconstruction using the ICBN as a donor to the lateral cord contribution to the median nerve, with a mean follow-up period of 41 months. A protocol evaluation was performed. Results: Four patients perceived the 1-green filament. The 2-blue, 3-purple and 4-red filaments were perceptible in one, two and three patients, respectively. According to Highet's scale, sensation recovered to S3 in two patients, to S2+ in two patients, to S2 in six patients, and S0 in one patient. Conclusion: The procedure using the ICBN as a sensory donor restores good intensity of sensation and shows good results in location of perception in patients with complete brachial plexus avulsion.

Restoration of sensory dysfunction following peripheral nerve injury by the polysaccharide from culinary and medicinal mushroom, Hericium erinaceus (Bull.: Fr. Pers. through its neuroregenerative action

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Kah-Hui WONG

2015-01-01

Full Text Available Abstract Peripheral nerves have the unique capability to regenerate after injury. Insights into regeneration of peripheral nerves after injury may have implications for neurodegenerative diseases of the nervous system. We investigated the ability of polysaccharide from Hericium erinaceus mushroom in the treatment of nerve injury following peroneal nerve crush in Sprague-Dawley rats by daily oral administration. In sensory functional recovery test, the time taken for the rats to withdraw its hind limb from contact with the hot plate was measured. The test revealed acceleration of sensory recovery in the polysaccharide group compared to negative controls. Further, peripheral nerve injury leads to changes at the remotely located DRG containing cell bodies of sensory neurons. Immunofluorescence studies showed that Akt and p38 MAPK were expressed in DRG and strongly upregulated in polysaccharide group after peripheral nerve injury. The intensity of endothelial cells antigen-1 that recognized endothelial cells in the blood vessels of distal segments in crushed nerves was significantly higher in the treated groups than in the negative control group. Our findings suggest that H. erinaceus is capable of accelerating sensory functional recovery after peripheral nerve injury and the effect involves the activation of protein kinase signaling pathways and restoration of blood-nerve barrier.

Variability of pudendal and median nerve sensory perception thresholds in healthy persons.

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Quaghebeur, Jörgen; Wyndaele, Jean-Jacques

2015-04-01

Normative current perception thresholds (CPTs) are used for the evaluation of sensory function in a variety of diseases. To evaluate the reproducibility of CPT measurements with sinusoidal current in healthy volunteers. Neuroselective CPT evaluations of the median and pudendal nerve in healthy volunteers were repeated with 1 week interval (T1 and T2). In the study group (N = 41) no difference between genders for age (MW-U: P = 0.91) and BMI (t-test: P = 0.18) were found. No significant difference between T1 and T2 was found (Paired t-test: all P-values > 0.05), although the intraclass correlation for each person was low. The variability of measures for the pudendal nerve was: ICC 2 kHz: 0.41; 250 Hz: 0.30; 5 Hz: 0.38, and for the median nerve respectively: 0.58; 0.46; 0.40. Normal CPTs were shown for the pudendal nerve: 2 kHz: 51%; 250 Hz: 76%; 5 Hz: 71%, and median nerve respectively: 78%; 98%; 80%. The pudendal nerve showed more deviating values compared to the median nerve. Both nerves showed deviating values. CPT values with sinusoidal current assessed with 1 week interval, showed a weak intraclass correlation. This finding limits the use of CPT values with this current for longitudinal studies. © 2014 Wiley Periodicals, Inc.

Reduced Renshaw Recurrent Inhibition after Neonatal Sciatic Nerve Crush in Rats

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Liang Shu

2014-01-01

Full Text Available Renshaw recurrent inhibition (RI plays an important gated role in spinal motion circuit. Peripheral nerve injury is a common disease in clinic. Our current research was designed to investigate the change of the recurrent inhibitory function in the spinal cord after the peripheral nerve crush injury in neonatal rat. Sciatic nerve crush was performed on 5-day-old rat puppies and the recurrent inhibition between lateral gastrocnemius-soleus (LG-S and medial gastrocnemius (MG motor pools was assessed by conditioning monosynaptic reflexes (MSR elicited from the sectioned dorsal roots and recorded either from the LG-S and MG nerves by antidromic stimulation of the synergist muscle nerve. Our results demonstrated that the MSR recorded from both LG-S or MG nerves had larger amplitude and longer latency after neonatal sciatic nerve crush. The RI in both LG-S and MG motoneuron pools was significantly reduced to virtual loss (15–20% of the normal RI size even after a long recovery period upto 30 weeks after nerve crush. Further, the degree of the RI reduction after tibial nerve crush was much less than that after sciatic nerve crush indicatig that the neuron-muscle disconnection time is vital to the recovery of the spinal neuronal circuit function during reinnervation. In addition, sciatic nerve crush injury did not cause any spinal motor neuron loss but severally damaged peripheral muscle structure and function. In conclusion, our results suggest that peripheral nerve injury during neonatal early development period would cause a more sever spinal cord inhibitory circuit damage, particularly to the Renshaw recurrent inhibition pathway, which might be the target of neuroregeneration therapy.

Roles of Sensory Nerves in the Regulation of Radiation-Induced Structural and Functional Changes in the Heart

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Sridharan, Vijayalakshmi; Tripathi, Preeti [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Sharma, Sunil [Department of Radiation Oncology, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Moros, Eduardo G. [Department of Radiation Oncology, Moffitt Cancer Center and Research Institute, Tampa, Florida (United States); Zheng, Junying [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Hauer-Jensen, Martin [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Surgical Service, Central Arkansas Veterans Healthcare System, Little Rock, Arkansas (United States); Boerma, Marjan, E-mail: mboerma@uams.edu [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States)

2014-01-01

Purpose: Radiation-induced heart disease (RIHD) is a chronic severe side effect of radiation therapy of intrathoracic and chest wall tumors. The heart contains a dense network of sensory neurons that not only are involved in monitoring of cardiac events such as ischemia and reperfusion but also play a role in cardiac tissue homeostasis, preconditioning, and repair. The purpose of this study was to examine the role of sensory nerves in RIHD. Methods and Materials: Male Sprague-Dawley rats were administered capsaicin to permanently ablate sensory nerves, 2 weeks before local image-guided heart x-ray irradiation with a single dose of 21 Gy. During the 6 months of follow-up, heart function was assessed with high-resolution echocardiography. At 6 months after irradiation, cardiac structural and molecular changes were examined with histology, immunohistochemistry, and Western blot analysis. Results: Capsaicin pretreatment blunted the effects of radiation on myocardial fibrosis and mast cell infiltration and activity. By contrast, capsaicin pretreatment caused a small but significant reduction in cardiac output 6 months after irradiation. Capsaicin did not alter the effects of radiation on cardiac macrophage number or indicators of autophagy and apoptosis. Conclusions: These results suggest that sensory nerves, although they play a predominantly protective role in radiation-induced cardiac function changes, may eventually enhance radiation-induced myocardial fibrosis and mast cell activity.

Roles of Sensory Nerves in the Regulation of Radiation-Induced Structural and Functional Changes in the Heart

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Sridharan, Vijayalakshmi; Tripathi, Preeti; Sharma, Sunil; Moros, Eduardo G.; Zheng, Junying; Hauer-Jensen, Martin; Boerma, Marjan

2014-01-01

Purpose: Radiation-induced heart disease (RIHD) is a chronic severe side effect of radiation therapy of intrathoracic and chest wall tumors. The heart contains a dense network of sensory neurons that not only are involved in monitoring of cardiac events such as ischemia and reperfusion but also play a role in cardiac tissue homeostasis, preconditioning, and repair. The purpose of this study was to examine the role of sensory nerves in RIHD. Methods and Materials: Male Sprague-Dawley rats were administered capsaicin to permanently ablate sensory nerves, 2 weeks before local image-guided heart x-ray irradiation with a single dose of 21 Gy. During the 6 months of follow-up, heart function was assessed with high-resolution echocardiography. At 6 months after irradiation, cardiac structural and molecular changes were examined with histology, immunohistochemistry, and Western blot analysis. Results: Capsaicin pretreatment blunted the effects of radiation on myocardial fibrosis and mast cell infiltration and activity. By contrast, capsaicin pretreatment caused a small but significant reduction in cardiac output 6 months after irradiation. Capsaicin did not alter the effects of radiation on cardiac macrophage number or indicators of autophagy and apoptosis. Conclusions: These results suggest that sensory nerves, although they play a predominantly protective role in radiation-induced cardiac function changes, may eventually enhance radiation-induced myocardial fibrosis and mast cell activity

Afferent fibers and sensory ganglion cells within the oculomotor nerve in some mammals and man. II. Electrophysiological investigations.

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Manni, E; Bortolami, R; Pettorossi, V E; Lucchi, M L; Callegari, E

1978-01-01

The main aim of the present study was to localize with electrophysiological techniques the central projections and terminations of the aberrant trigeminal fibres contained in the oculomotor nerve of the lamb. After severing a trigeminal root, single-shock electrical stimulation of the trigeminal axons present in the central stump of the ipsilateral oculomotor nerve evoked field potentials in the area of, i) the subnucleus gelatinosus of the nucleus caudalis trigemini at the level of C1-C2; ii) the main sensory trigeminal nucleus; iii) the descending trigeminal nucleus and tract; iv) the adjacent reticular formation. Units whose discharge rate was influenced by such a stimulation were also found in the same territories. These regions actually exhibited degenerations after cutting an oculomotor nerve. We conclude, therefore, that the trigeminal fibres which leave the Vth nerve at the level of the cavernous sinus and enter the brain stem through the IIIrd nerve, end in the same structures which receive the terminations of the afferent fibres entering the brain stem through the sensory trigeminal root.

Different Effects of Implanting Sensory Nerve or Blood Vessel on the Vascularization, Neurotization, and Osteogenesis of Tissue-Engineered Bone In Vivo

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Fan, Jun-jun; Mu, Tian-wang; Qin, Jun-jun; Bi, Long; Pei, Guo-xian

2014-01-01

To compare the different effects of implanting sensory nerve tracts or blood vessel on the osteogenesis, vascularization, and neurotization of the tissue-engineered bone in vivo, we constructed the tissue engineered bone and implanted the sensory nerve tracts (group SN), blood vessel (group VB), or nothing (group Blank) to the side channel of the bone graft to repair the femur defect in the rabbit. Better osteogenesis was observed in groups SN and VB than in group Blank, and no significant difference was found between groups SN and VB at 4, 8, and 12 weeks postoperatively. The neuropeptides expression and the number of new blood vessels in the bone tissues were increased at 8 weeks and then decreased at 12 weeks in all groups and were highest in group VB and lowest in group Blank at all three time points. We conclude that implanting either blood vessel or sensory nerve tract into the tissue-engineered bone can significantly enhance both the vascularization and neurotization simultaneously to get a better osteogenesis effect than TEB alone, and the method of implanting blood vessel has a little better effect of vascularization and neurotization but almost the same osteogenesis effect as implanting sensory nerve. PMID:25101279

Pudendal and median nerve sensory perception threshold: a comparison between normative studies.

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Quaghebeur, Jörgen; Wyndaele, Jean Jacques

2014-12-01

For the evaluation of sensory innervation, normative data are necessary as a comparison. To compare our current perception thresholds (CPTs) with normative data from other research. Healthy volunteers were assessed for 2000, 250, and 5 Hz CPTs of the median and pudendal nerve and data were compared with other studies. Normative data in the studied group n = 41 (male: 21; female: 20) for the median nerve, 2 kHz, 250 Hz, and 5 Hz were respectively: 241.85 ± 67.72 (140-444); 106.27 ± 39.12 (45-229); 82.05 ± 43.40 (13-271). Pudendal nerve CPTs 250 Hz were: 126.44 ± 69.46 (6-333). For men 2 kHz: 349.95 ± 125.76 (100-588); 5 Hz: 132.67 ± 51.81 (59-249) and women 2 kHz:226.20 ± 119.65 (64-528); 5 Hz: 92.45 ± 44.66 (35-215). For the median nerve no statistical differences for gender were shown. For the pudendal nerve, only 250 Hz showed no difference for gender (t-test: 0.516). Comparison of our data with CPTs of other normative data showed no agreement for the pudendal nerve. For the median nerve only 2 kHz showed agreement in three studies and for 5 Hz with one study. Comparing normative data of multiple studies shows a variety of results and poor agreement. Therefore, referring to normative data of other studies should be handled with caution.

Haemangioblastoma of a cervical sensory nerve root in Von Hippel-Lindau syndrome.

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McEvoy, A W; Benjamin, E; Powell, M P

2000-10-01

Spinal haemangioblastomas are rare, accounting for only about 7% of all central nervous system cases. The case of a 40-year-old woman with a haemangioblastoma arising solely from a cervical sensory nerve root is presented. At operation via a cervical laminectomy, it was possible to resect the tumour en masse with the sensory ramus, by extending the laminectomy through the exit foramen for C6. Haemangioblastomas are commonly intramedullary, and have only been reported in this location on one previous occasion. The patient has Von Hippel-Lindau syndrome and a history of multiple solid tumours. The possible role of the Von Hippel-Lindau tumour suppressor gene in the pathogenesis of these neoplasms is discussed.

Traditional Japanese medicines inhibit compound action potentials in the frog sciatic nerve.

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Matsushita, Akitomo; Fujita, Tsugumi; Ohtsubo, Sena; Kumamoto, Eiichi

2016-02-03

Traditional Japanese (Kampo) medicines have a variety of clinical effects including pain alleviation, but evidence for a mechanism for their pain relief has not yet been elucidated fully. Considering that Kampo medicine contains many plant-derived chemicals having an ability to inhibit nerve action potential conduction, it is possible that this medicine inhibits nerve conduction. The purpose of the present study was to know how various Kampo medicines affect nerve conduction. We examined the effects of Kampo and crude medicines on compound action potentials (CAPs) recorded from the frog sciatic nerve by using the air-gap method. Daikenchuto, rikkosan, kikyoto, rikkunshito, shakuyakukanzoto and kakkonto concentration-dependently reduced the peak amplitude of the CAP. Among the Kampo medicines, daikenchuto was the most effective in inhibiting CAPs. Daikenchuto is composed of three kinds of crude medicine, Japanese pepper, processed ginger and ginseng radix. When the crude medicines were tested, Japanese pepper and processed ginger reduced CAP peak amplitudes, while ginseng radix hardly affected CAPs. Moreover, there was an interaction between the Japanese pepper and processed ginger activities in such that one medicine at low but not high concentrations increased the extent of the inhibition by the other one that was co-applied. Kampo medicines have an ability to inhibit nerve conduction. This action of daikenchuto is due to Japanese pepper and processed ginger but not ginseng radix, probably through an interaction between Japanese pepper and processed ginger in a manner dependent on their concentrations. Nerve conduction inhibition could contribute to at least a part of Kampo medicine's clinical effects such as pain alleviation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Alpha-Synuclein Pathology in Sensory Nerve Terminals of the Upper Aerodigestive Tract of Parkinson's Disease Patients.

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Mu, Liancai; Chen, Jingming; Sobotka, Stanislaw; Nyirenda, Themba; Benson, Brian; Gupta, Fiona; Sanders, Ira; Adler, Charles H; Caviness, John N; Shill, Holly A; Sabbagh, Marwan; Samanta, Johan E; Sue, Lucia I; Beach, Thomas G

2015-08-01

Dysphagia is common in Parkinson's disease (PD) and causes significant morbidity and mortality. PD dysphagia has usually been explained as dysfunction of central motor control, much like other motor symptoms that are characteristic of the disease. However, PD dysphagia does not correlate with severity of motor symptoms nor does it respond to motor therapies. It is known that PD patients have sensory deficits in the pharynx, and that impaired sensation may contribute to dysphagia. However, the underlying cause of the pharyngeal sensory deficits in PD is not known. We hypothesized that PD dysphagia with sensory deficits may be due to degeneration of the sensory nerve terminals in the upper aerodigestive tract (UAT). We have previously shown that Lewy-type synucleinopathy (LTS) is present in the main pharyngeal sensory nerves of PD patients, but not in controls. In this study, the sensory terminals in UAT mucosa were studied to discern the presence and distribution of LTS. Whole-mount specimens (tongue-pharynx-larynx-upper esophagus) were obtained from 10 deceased human subjects with clinically diagnosed and neuropathologically confirmed PD (five with dysphagia and five without) and four age-matched healthy controls. Samples were taken from six sites and immunostained for phosphorylated α-synuclein (PAS). The results showed the presence of PAS-immunoreactive (PAS-ir) axons in all the PD subjects and in none of the controls. Notably, PD patients with dysphagia had more PAS-ir axons in the regions that are critical for initiating the swallowing reflex. These findings suggest that Lewy pathology affects mucosal sensory axons in specific regions of the UAT and may be related to PD dysphagia.

Palmitoylethanolamide Inhibits Glutamate Release in Rat Cerebrocortical Nerve Terminals

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Tzu-Yu Lin

2015-03-01

Full Text Available The effect of palmitoylethanolamide (PEA, an endogenous fatty acid amide displaying neuroprotective actions, on glutamate release from rat cerebrocortical nerve terminals (synaptosomes was investigated. PEA inhibited the Ca2+-dependent release of glutamate, which was triggered by exposing synaptosomes to the potassium channel blocker 4-aminopyridine. This release inhibition was concentration dependent, associated with a reduction in cytosolic Ca2+ concentration, and not due to a change in synaptosomal membrane potential. The glutamate release-inhibiting effect of PEA was prevented by the Cav2.1 (P/Q-type channel blocker ω-agatoxin IVA or the protein kinase A inhibitor H89, not affected by the intracellular Ca2+ release inhibitors dantrolene and CGP37157, and partially antagonized by the cannabinoid CB1 receptor antagonist AM281. Based on these results, we suggest that PEA exerts its presynaptic inhibition, likely through a reduction in the Ca2+ influx mediated by Cav2.1 (P/Q-type channels, thereby inhibiting the release of glutamate from rat cortical nerve terminals. This release inhibition might be linked to the activation of presynaptic cannabinoid CB1 receptors and the suppression of the protein kinase A pathway.

Sensory stimulation for lowering intraocular pressure, improving blood flow to the optic nerve and neuroprotection in primary open-angle glaucoma.

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Rom, Edith

2013-12-01

Primary open-angle glaucoma is a group of optic neuropathies that can lead to irreversible blindness. Sensory stimulation in the form of acupuncture or ear acupressure may contribute to protecting patients from blindness when used as a complementary method to orthodox treatment in the form of drops, laser or surgery. The objective of this article is to provide a narrative overview of the available literature up to July 2012. It summarises reported evidence on the potential beneficial effects of sensory stimulation for glaucoma. Sensory stimulation appears to significantly enhance the pressure-lowering effect of orthodox treatments. Studies suggest that it may also improve blood flow to the eye and optic nerve head. Furthermore, it may play a role in neuroprotection through regulating nerve growth factor and brain-derived neurotrophic factor and their receptors, thereby encouraging the survival pathway in contrast to the pathway to apoptosis. Blood flow and neuroprotection are areas that are not directly influenced by orthodox treatment modalities. Numerous different treatment protocols were used to investigate the effect of sensory stimulation on intraocular pressure, blood flow or neuroprotection of the retina and optic nerve in the animal model and human pilot studies. Objective outcomes were reported to have been evaluated with Goldmann tonometry, Doppler ultrasound techniques and electrophysiology (pattern electroretinography, visually evoked potentials), and supported with histological studies in the animal model. Taken together, reported evidence from these studies strongly suggests that sensory stimulation is worthy of further research.

Alpha-Synuclein Pathology in Sensory Nerve Terminals of the Upper Aerodigestive Tract of Parkinson’s Disease Patients

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Mu, Liancai; Chen, Jingming; Sobotka, Stanislaw; Nyirenda, Themba; Benson, Brian; Gupta, Fiona; Sanders, Ira; Adler, Charles H.; Caviness, John N.; Shill, Holly A.; Sabbagh, Marwan; Samanta, Johan E.; Sue, Lucia I.; Beach, Thomas G.

2015-01-01

Dysphagia is common in Parkinson’s disease (PD) and causes significant morbidity and mortality. PD dysphagia has usually been explained as dysfunction of central motor control, much like other motor symptoms that are characteristic of the disease. However, PD dysphagia does not correlate with severity of motor symptoms nor does it respond to motor therapies. It is known that PD patients have sensory deficits in the pharynx, and that impaired sensation may contribute to dysphagia. However, the underlying cause of the pharyngeal sensory deficits in PD is not known. We hypothesized that PD dysphagia with sensory deficits may be due to degeneration of the sensory nerve terminals in the upper aerodigestive tract (UAT). We have previously shown that Lewy-type synucleinopathy (LTS) is present in the main pharyngeal sensory nerves of PD patients, but not in controls. In this study, the sensory terminals in UAT mucosa were studied to discern the presence and distribution of LTS. Whole-mount specimens (tongue-pharynx-larynx-upper esophagus) were obtained from 10 deceased human subjects with clinically diagnosed and neuropathologically confirmed PD (five with dysphagia and five without) and four age-matched healthy controls. Samples were taken from six sites and immunostained for phosphorylated α-synuclein (PAS). The results showed the presence of PAS-immunoreactive (PAS-ir) axons in all the PD subjects and in none of the controls. Notably, PD patients with dysphagia had more PAS-ir axons in the regions that are critical for initiating the swallowing reflex. These findings suggest that Lewy pathology affects mucosal sensory axons in specific regions of the UAT and may be related to PD dysphagia. PMID:26041249

The vestibulocochlear nerve (VIII).

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Benoudiba, F; Toulgoat, F; Sarrazin, J-L

2013-10-01

The vestibulocochlear nerve (8th cranial nerve) is a sensory nerve. It is made up of two nerves, the cochlear, which transmits sound and the vestibular which controls balance. It is an intracranial nerve which runs from the sensory receptors in the internal ear to the brain stem nuclei and finally to the auditory areas: the post-central gyrus and superior temporal auditory cortex. The most common lesions responsible for damage to VIII are vestibular Schwannomas. This report reviews the anatomy and various investigations of the nerve. Copyright © 2013. Published by Elsevier Masson SAS.

Reflex vocal fold adduction in the porcine model: the effects of stimuli delivered to various sensory nerves.

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Woo, Jeong-Soo; Hundal, Jagdeep S; Sasaki, Clarence T; Abdelmessih, Mikhail W; Kelleher, Stephen P

2008-10-01

The aim of this study was to identify a panel of sensory nerves capable of eliciting an evoked glottic closure reflex (GCR) and to quantify the glottic closing force (GCF) of these responses in a porcine model. In 5 pigs, the internal branch of the superior laryngeal nerve (iSLN) and the trigeminal, pharyngeal plexus, glossopharyngeal, radial, and intercostal nerves were surgically isolated and electrically stimulated. During stimulation of each nerve, the GCR was detected by laryngeal electromyography and the GCF was measured with a pressure transducer. The only nerve that elicited the GCR in the 5 pigs was the iSLN. The average GCF was 288.9 mm Hg. This study demonstrates that the only afferent nerve that elicits the GCR in pigs is the iSLN, and that it should remain the focus of research for the rehabilitation of patients with absent or defective reflex vocal fold adduction.

Chitin biological absorbable catheters bridging sural nerve grafts transplanted into sciatic nerve defects promote nerve regeneration.

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Wang, Zhi-Yong; Wang, Jian-Wei; Qin, Li-Hua; Zhang, Wei-Guang; Zhang, Pei-Xun; Jiang, Bao-Guo

2018-06-01

To investigate the efficacy of chitin biological absorbable catheters in a rat model of autologous nerve transplantation. A segment of sciatic nerve was removed to produce a sciatic nerve defect, and the sural nerve was cut from the ipsilateral leg and used as a graft to bridge the defect, with or without use of a chitin biological absorbable catheter surrounding the graft. The number and morphology of regenerating myelinated fibers, nerve conduction velocity, nerve function index, triceps surae muscle morphology, and sensory function were evaluated at 9 and 12 months after surgery. All of the above parameters were improved in rats in which the nerve graft was bridged with chitin biological absorbable catheters compared with rats without catheters. The results of this study indicate that use of chitin biological absorbable catheters to surround sural nerve grafts bridging sciatic nerve defects promotes recovery of structural, motor, and sensory function and improves muscle fiber morphology. © 2018 John Wiley & Sons Ltd.

A somatotopic bidirectional hand prosthesis with transcutaneous electrical nerve stimulation based sensory feedback.

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D'Anna, Edoardo; Petrini, Francesco M; Artoni, Fiorenzo; Popovic, Igor; Simanić, Igor; Raspopovic, Stanisa; Micera, Silvestro

2017-09-07

According to amputees, sensory feedback is amongst the most important features lacking from commercial prostheses. Although restoration of touch by means of implantable neural interfaces has been achieved, these approaches require surgical interventions, and their long-term usability still needs to be fully investigated. Here, we developed a non-invasive alternative which maintains some of the advantages of invasive approaches, such as a somatotopic sensory restitution scheme. We used transcutaneous electrical nerve stimulation (TENS) to induce referred sensations to the phantom hand of amputees. These sensations were characterized in four amputees over two weeks. Although the induced sensation was often paresthesia, the location corresponded to parts of the innervation regions of the median and ulnar nerves, and electroencephalographic (EEG) recordings confirmed the presence of appropriate responses in relevant cortical areas. Using these sensations as feedback during bidirectional prosthesis control, the patients were able to perform several functional tasks that would not be possible otherwise, such as applying one of three levels of force on an external sensor. Performance during these tasks was high, suggesting that this approach could be a viable alternative to the more invasive solutions, offering a trade-off between the quality of the sensation, and the invasiveness of the intervention.

Structural and Functional Substitution of Deleted Primary Sensory Neurons by New Growth from Intrinsic Spinal Cord Nerve Cells: An Alternative Concept in Reconstruction of Spinal Cord Circuits

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Nicholas D. James

2017-07-01

Full Text Available In a recent clinical report, return of the tendon stretch reflex was demonstrated after spinal cord surgery in a case of total traumatic brachial plexus avulsion injury. Peripheral nerve grafts had been implanted into the spinal cord to reconnect to the peripheral nerves for motor and sensory function. The dorsal root ganglia (DRG containing the primary sensory nerve cells had been surgically removed in order for secondary or spinal cord sensory neurons to extend into the periphery and replace the deleted DRG neurons. The present experimental study uses a rat injury model first to corroborate the clinical finding of a re-established spinal reflex arch, and second, to elucidate some of the potential mechanisms underlying these findings by means of morphological, immunohistochemical, and electrophysiological assessments. Our findings indicate that, after spinal cord surgery, the central nervous system sensory system could replace the traumatically detached original peripheral sensory connections through new neurite growth from dendrites.

Influence of local noxious heat stimulation on sensory nerve activity in the feline dental pulp.

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Ahlberg, K F

1978-05-01

The present investigation was undertaken to develop an experimental model in which noxious heat stimulation was used to produce increased intradental sensory nerve activity in canine teeth of anesthetized cats. Two techniques were evaluated in which both the method of recording and the nature of the stimulus varied. Slow heating (approx 1 degree C/s) to 47 degree C of the tooth surface (combined with recording from electrodes in open dentinal cavities) did not produce any persistent nerve activity. Repeated periods of brief intense heating (approx 60 degrees C/s) (combined with recording from amalgam electrodes placed on cavity floors) resulted in an immediate response and an afterdischarge (phase 3) generally persisting for 20--60 min. Maximum phase 3 activity was characteristic for the individual cat and ranged from 0.2 to 50.2 imp/s. mean value 10.6 imp/s (S.D. +/- 9.2). A systematically higher phase 3 activity was recorded in lower compared to upper canine teeth (p less than 0.05). The maximum phase 3 response generally occurred after 3-8 stimulations; the median number of required stimuli was 3. Repeated brief heat stimulations combined with the closed cavity recording technique may be used as an experimental model by which the mechanisms behind increases in intradental sensory nerve activity associated with tissue damage can be studied.

Pharmacological analysis of the inhibition produced by moxonidine and agmatine on the vasodepressor sensory CGRPergic outflow in pithed rats.

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Rubio-Beltrán, Eloísa; Labastida-Ramírez, Alejandro; Hernández-Abreu, Oswaldo; MaassenVanDenBrink, Antoinette; Villalón, Carlos M

2017-10-05

Calcitonin gene-related peptide (CGRP) plays a role in several (patho)physiological functions, and modulation of its release is considered a therapeutic target. In this respect, electrical spinal (T 9 --T 12 ) stimulation of the perivascular sensory outflow in pithed rats produces vasodepressor responses mediated by CGRP release. This study investigated the role of imidazoline I 1 and I 2 receptors in the inhibition by moxonidine and agmatine of these vasodepressor responses. Male Wistar pithed rats (pretreated i.v. with 25mg/kg gallamine and 2mg/kg⋅min hexamethonium) received i.v. continuous infusions of methoxamine (20μg/kg⋅min) followed by physiological saline (0.02ml/min), moxonidine (1, 3, 10 or 30μg/kg⋅min) or agmatine (1000 or 3000μg/kg⋅min). Under these conditions, electrical stimulation (0.56-5.6Hz; 50V; 2ms) of the spinal cord (T 9 -T 12 ) produced frequency-dependent vasodepressor responses which were: (i) unchanged during saline infusion; and (ii) inhibited during the above infusions of moxonidine or agmatine. Moreover, using i.v. administrations, the inhibition by 3μg/kg⋅min moxonidine or 3000μg/kg⋅min agmatine (which failed to inhibit the vasodepressor responses by α-CGRP; 0.1-1µg/kg) was: (i) unaltered after saline (1ml/kg), rauwolscine (300μg/kg; α 2 -adrenoceptor antagonist) or BU224 (300μg/kg; imidazoline I 2 receptor antagonist); and (ii) reversed after AGN 192403 (3000μg/kg; imidazoline I 1 receptor antagonist). This reversion was relatively more pronounced after AGN 192403 plus rauwolscine. These blocking doses of antagonists lacked any effects on the electrically-induced vasodepressor responses. Therefore, the inhibition of the vasodepressor sensory CGRPergic outflow by moxonidine and agmatine is mainly mediated by prejunctional imidazoline I 1 receptors on perivascular sensory nerves. Copyright © 2017 Elsevier B.V. All rights reserved.

An artificial arm/hand system with a haptic sensory function using electric stimulation of peripheral sensory nerve fibers.

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Mabuchi, Kunihiko

2013-01-01

We are currently developing an artificial arm/hand system which is capable of sensing stimuli and then transferring these stimuli to users as somatic sensations. Presently, we are evoking the virtual somatic sensations by electrically stimulating a sensory nerve fiber which innervates a single mechanoreceptor unit at the target area; this is done using a tungsten microelectrode that was percutaneously inserted into the use's peripheral nerve (a microstimulation method). The artificial arm/hand system is composed of a robot hand equipped with a pressure sensor system on its fingers. The sensor system detects mechanical stimuli, which are transferred to the user by means of the microstimulation method so that the user experiences the stimuli as the corresponding somatic sensations. In trials, the system worked satisfactorily and there was a good correlation between the pressure applied to the pressure sensors on the robot fingers and the subjective intensities of the evoked pressure sensations.

Effect of Ranirestat on Sensory and Motor Nerve Function in Japanese Patients with Diabetic Polyneuropathy: A Randomized Double-Blind Placebo-Controlled Study

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Satoh, Jo; Kohara, Nobuo; Sekiguchi, Kenji; Yamaguchi, Yasuyuki

2016-01-01

We conducted a 26-week oral-administration study of ranirestat (an aldose reductase inhibitor) at a once-daily dose of 20 mg to evaluate its efficacy and safety in Japanese patients with diabetic polyneuropathy (DPN). The primary endpoint was summed change in sensory nerve conduction velocity (NCV) for the bilateral sural and proximal median sensory nerves. The sensory NCV was significantly (P = 0.006) improved by ranirestat. On clinical symptoms evaluated with the use of modified Toronto Clinical Neuropathy Score (mTCNS), obvious efficacy was not found in total score. However, improvement in the sensory test domain of the mTCNS was significant (P = 0.037) in a subgroup of patients diagnosed with neuropathy according to the TCNS severity classification. No clinically significant effects on safety parameters including hepatic and renal functions were observed. Our results indicate that ranirestat is effective on DPN (Japic CTI-121994). PMID:26881251

Effect of Ranirestat on Sensory and Motor Nerve Function in Japanese Patients with Diabetic Polyneuropathy: A Randomized Double-Blind Placebo-Controlled Study

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Jo Satoh

2016-01-01

Full Text Available We conducted a 26-week oral-administration study of ranirestat (an aldose reductase inhibitor at a once-daily dose of 20 mg to evaluate its efficacy and safety in Japanese patients with diabetic polyneuropathy (DPN. The primary endpoint was summed change in sensory nerve conduction velocity (NCV for the bilateral sural and proximal median sensory nerves. The sensory NCV was significantly (P=0.006 improved by ranirestat. On clinical symptoms evaluated with the use of modified Toronto Clinical Neuropathy Score (mTCNS, obvious efficacy was not found in total score. However, improvement in the sensory test domain of the mTCNS was significant (P=0.037 in a subgroup of patients diagnosed with neuropathy according to the TCNS severity classification. No clinically significant effects on safety parameters including hepatic and renal functions were observed. Our results indicate that ranirestat is effective on DPN (Japic CTI-121994.

Disruption of spinal cord white matter and sciatic nerve geometry inhibits axonal growth in vitro in the absence of glial scarring

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Crutcher Keith A

2001-05-01

Full Text Available Abstract Background Axons within the mature mammalian central nervous system fail to regenerate following injury, usually resulting in long-lasting motor and sensory deficits. Studies involving transplantation of adult neurons into white matter implicate glial scar-associated factors in regeneration failure. However, these studies cannot distinguish between the effects of these factors and disruption of the spatial organization of cells and molecular factors (disrupted geometry. Since white matter can support or inhibit neurite growth depending on the geometry of the fiber tract, the present study sought to determine whether disrupted geometry is sufficient to inhibit neurite growth. Results Embryonic chick sympathetic neurons were cultured on unfixed longitudinal cryostat sections of mature rat spinal cord or sciatic nerve that had been crushed with forceps ex vivo then immediately frozen to prevent glial scarring. Neurite growth on uncrushed portions of spinal cord white matter or sciatic nerve was extensive and highly parallel with the longitudinal axis of the fiber tract but did not extend onto crushed portions. Moreover, neurite growth from neurons attached directly to crushed white matter or nerve tissue was shorter and less parallel compared with neurite growth on uncrushed tissue. In contrast, neurite growth appeared to be unaffected by crushed spinal cord gray matter. Conclusions These observations suggest that glial scar-associated factors are not necessary to block axonal growth at sites of injury. Disruption of fiber tract geometry, perhaps involving myelin-associated neurite-growth inhibitors, may be sufficient to pose a barrier to regenerating axons in spinal cord white matter and peripheral nerves.

Imaging sensory effects of occipital nerve stimulation: a new computer-based method in neuromodulation.

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Göbel, Anna; Göbel, Carl H; Heinze, Axel; Heinze-Kuhn, Katja; Petersen, Inga; Meinecke, Christoph; Clasen, Svenja; Niederberger, Uwe; Rasche, Dirk; Mehdorn, Hubertus M; Göbel, Hartmut

2015-01-01

Within the last years, occipital nerve stimulation (ONS) has proven to be an important method in the treatment of severe therapy-resistant neurological pain disorders. The correspondence between lead placement as well as possible stimulation parameters and the resulting stimulation effects remains unclear. The method aims to directly relate the neuromodulatory mechanisms with the clinical treatment results, to achieve insight in the mode of action of neuromodulation, to identify the most effective stimulation sets and to optimize individual treatment effects. We describe a new computer-based imaging method for mapping the spatial, cognitive and affective sensory effects of ONS. The procedure allows a quantitative and qualitative analysis of the relationship between lead positioning, the stimulation settings as well as the sensory and clinical stimulation effects. A regular mapping of stimulation and sensory parameters allows a coordinated monitoring. The stimulation results can be reviewed and compared with regards to clinical effectiveness. Copyright © 2015 Elsevier Inc. All rights reserved.

Sensory feedback by peripheral nerve stimulation improves task performance in individuals with upper limb loss using a myoelectric prosthesis.

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Schiefer, Matthew; Tan, Daniel; Sidek, Steven M; Tyler, Dustin J

2016-02-01

Tactile feedback is critical to grip and object manipulation. Its absence results in reliance on visual and auditory cues. Our objective was to assess the effect of sensory feedback on task performance in individuals with limb loss. Stimulation of the peripheral nerves using implanted cuff electrodes provided two subjects with sensory feedback with intensity proportional to forces on the thumb, index, and middle fingers of their prosthetic hand during object manipulation. Both subjects perceived the sensation on their phantom hand at locations corresponding to the locations of the forces on the prosthetic hand. A bend sensor measured prosthetic hand span. Hand span modulated the intensity of sensory feedback perceived on the thenar eminence for subject 1 and the middle finger for subject 2. We performed three functional tests with the blindfolded subjects. First, the subject tried to determine whether or not a wooden block had been placed in his prosthetic hand. Second, the subject had to locate and remove magnetic blocks from a metal table. Third, the subject performed the Southampton Hand Assessment Procedure (SHAP). We also measured the subject's sense of embodiment with a survey and his self-confidence. Blindfolded performance with sensory feedback was similar to sighted performance in the wooden block and magnetic block tasks. Performance on the SHAP, a measure of hand mechanical function and control, was similar with and without sensory feedback. An embodiment survey showed an improved sense of integration of the prosthesis in self body image with sensory feedback. Sensory feedback by peripheral nerve stimulation improved object discrimination and manipulation, embodiment, and confidence. With both forms of feedback, the blindfolded subjects tended toward results obtained with visual feedback.

Anodal sensory nerve action potentials: From physiological understanding to potential clinical applicability.

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Leote, Joao; Pereira, Pedro; Cabib, Christopher; Cipullo, Federica; Valls-Sole, Josep

2016-06-01

Low-intensity electrical stimuli of digital nerves may generate a double peak potential (DPp), composed of a cathodal (caAP) and an anodal (anAP) potential in orthodromic recordings. We studied the effects on caAP and anAP of stimuli of variable intensity, duration, and frequency. We also applied a conditioning stimulus to study potential differences in recovery time. The anAP was obtained in 33 of 40 healthy subjects (82.5%) and 4 of 20 patients with various types of sensory neuropathies (20%). Changes in stimulus duration and intensity had reciprocal effects on the amplitude of the anAP and the caAP. There were significant differences in recovery time between caAP and anAP after a conditioning stimulus. The caAP and anAP are 2 interdependent waveforms generated by different effects of the same stimulus over axons at the verge of depolarization. Muscle Nerve 53: 897-905, 2016. © 2015 Wiley Periodicals, Inc.

Imbalance between sympathetic and sensory innervation in peritoneal endometriosis.

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Arnold, Julia; Barcena de Arellano, Maria L; Rüster, Carola; Vercellino, Giuseppe F; Chiantera, Vito; Schneider, Achim; Mechsner, Sylvia

2012-01-01

To investigate possible mechanisms of pain pathophysiology in patients with peritoneal endometriosis, a clinical study on sensory and sympathetic nerve fibre sprouting in endometriosis was performed. Peritoneal lesions (n=40) and healthy peritoneum (n=12) were immunostained and analysed with anti-protein gene product 9.5 (PGP 9.5), anti-substance P (SP) and anti-tyrosine hydroxylase (TH), specific markers for intact nerve fibres, sensory nerve fibres and sympathetic nerve fibres, respectively, to identify the ratio of sympathetic and sensory nerve fibres. In addition, immune cell infiltrates in peritoneal endometriotic lesions were analysed and the nerve growth factor (NGF) and interleukin (IL)-1β expression was correlate with the nerve fibre density. Peritoneal fluids from patients with endometriosis (n=40) and without endometriosis (n=20) were used for the in vitro neuronal growth assay. Cultured chicken dorsal root ganglia (DRG) and sympathetic ganglia were stained with anti-growth associated protein 43 (anti-GAP 43), anti-SP and anti-TH. We could detect an increased sensory and decreased sympathetic nerve fibres density in peritoneal lesions compared to healthy peritoneum. Peritoneal fluids of patients with endometriosis compared to patients without endometriosis induced an increased sprouting of sensory neurites from DRG and decreased neurite outgrowth from sympathetic ganglia. In conclusion, this study demonstrates an imbalance between sympathetic and sensory nerve fibres in peritoneal endometriosis, as well as an altered modulation of peritoneal fluids from patients with endometriosis on sympathetic and sensory innervation which might directly be involved in the maintenance of inflammation and pain. Copyright © 2011 Elsevier Inc. All rights reserved.

Evaluation of Morphological and Functional Nerve Recovery of Rat Sciatic Nerve with a Hyaff11-Based Nerve Guide

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K. Jansen

2006-01-01

Full Text Available Application of a Hyaff11-based nerve guide was studied in rats. Functional tests were performed to study motor nerve recovery. A withdrawal reflex test was performed to test sensory recovery. Morphology was studied by means of histology on explanted tissue samples. Motor nerve recovery was established within 7 weeks. Hereafter, some behavioral parameters like alternating steps showed an increase in occurence, while others remained stable. Sensory function was observed within the 7 weeks time frame. Nerve tissue had bridged the 10-mm gap within 7 weeks. The average nerve fiber surface area increased significantly in time. In situ degradation of the nerve conduit was fully going on at week 7 and tubes had collapsed by then. At weeks 15 and 21, the knitted tube wall structure was completely surrounded by macrophages and giant cells, and matrix was penetrating the tube wall. We conclude that a Hyaff11-based nerve guide can be used to bridge short peripheral nerve defects in rat. However, adaptations need to be made.

Sensory and motor neuropathy in a Border Collie.

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Harkin, Kenneth R; Cash, Walter C; Shelton, G Diane

2005-10-15

A 5-month-old female Border Collie was evaluated because of progressive hind limb ataxia. The predominant clinical findings suggested a sensory neuropathy. Sensory nerve conduction velocity was absent in the tibial, common peroneal, and radial nerves and was decreased in the ulnar nerve; motor nerve conduction velocity was decreased in the tibial, common peroneal, and ulnar nerves. Histologic examination of nerve biopsy specimens revealed considerable nerve fiber depletion; some tissue sections had myelin ovoids, foamy macrophages, and axonal degeneration in remaining fibers. Marked depletion of most myelinated fibers within the peroneal nerve (a mixed sensory and motor nerve) supported the electrodiagnostic findings indicative of sensorimotor neuropathy. Progressive deterioration in motor function occurred over the following 19 months until the dog was euthanatized. A hereditary link was not established, but a littermate was similarly affected. The hereditary characteristic of this disease requires further investigation.

Miconazole enhances nerve regeneration and functional recovery after sciatic nerve crush injury.

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Lin, Tao; Qiu, Shuai; Yan, Liwei; Zhu, Shuang; Zheng, Canbin; Zhu, Qingtang; Liu, Xiaolin

2018-05-01

Improving axonal outgrowth and remyelination is crucial for peripheral nerve regeneration. Miconazole appears to enhance remyelination in the central nervous system. In this study we assess the effect of miconazole on axonal regeneration using a sciatic nerve crush injury model in rats. Fifty Sprague-Dawley rats were divided into control and miconazole groups. Nerve regeneration and myelination were determined using histological and electrophysiological assessment. Evaluation of sensory and motor recovery was performed using the pinprick assay and sciatic functional index. The Cell Counting Kit-8 assay and Western blotting were used to assess the proliferation and neurotrophic expression of RSC 96 Schwann cells. Miconazole promoted axonal regrowth, increased myelinated nerve fibers, improved sensory recovery and walking behavior, enhanced stimulated amplitude and nerve conduction velocity, and elevated proliferation and neurotrophic expression of RSC 96 Schwann cells. Miconazole was beneficial for nerve regeneration and functional recovery after peripheral nerve injury. Muscle Nerve 57: 821-828, 2018. © 2017 Wiley Periodicals, Inc.

Sensory feedback by peripheral nerve stimulation improves task performance in individuals with upper limb loss using a myoelectric prosthesis

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Schiefer, Matthew; Tan, Daniel; Sidek, Steven M.; Tyler, Dustin J.

2016-02-01

Objective. Tactile feedback is critical to grip and object manipulation. Its absence results in reliance on visual and auditory cues. Our objective was to assess the effect of sensory feedback on task performance in individuals with limb loss. Approach. Stimulation of the peripheral nerves using implanted cuff electrodes provided two subjects with sensory feedback with intensity proportional to forces on the thumb, index, and middle fingers of their prosthetic hand during object manipulation. Both subjects perceived the sensation on their phantom hand at locations corresponding to the locations of the forces on the prosthetic hand. A bend sensor measured prosthetic hand span. Hand span modulated the intensity of sensory feedback perceived on the thenar eminence for subject 1 and the middle finger for subject 2. We performed three functional tests with the blindfolded subjects. First, the subject tried to determine whether or not a wooden block had been placed in his prosthetic hand. Second, the subject had to locate and remove magnetic blocks from a metal table. Third, the subject performed the Southampton Hand Assessment Procedure (SHAP). We also measured the subject’s sense of embodiment with a survey and his self-confidence. Main results. Blindfolded performance with sensory feedback was similar to sighted performance in the wooden block and magnetic block tasks. Performance on the SHAP, a measure of hand mechanical function and control, was similar with and without sensory feedback. An embodiment survey showed an improved sense of integration of the prosthesis in self body image with sensory feedback. Significance. Sensory feedback by peripheral nerve stimulation improved object discrimination and manipulation, embodiment, and confidence. With both forms of feedback, the blindfolded subjects tended toward results obtained with visual feedback.

Sensory-motor axonal polyneuropathy involving cranial nerves: An uncommon manifestation of disulfiram toxicity.

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Santos, Telma; Martins Campos, António; Morais, Hugo

2017-01-01

Disulfiram (tetraethylthiuram disulfide) has been used for the treatment of alcohol dependence. An axonal sensory-motor polyneuropathy with involvement of cranial pairs due to disulfiram is exceedingly rare. The authors report a unique case of an extremely severe axonal polyneuropathy involving cranial nerves that developed within weeks after a regular dosage of 500mg/day disulfiram. To the authors best knowledge, such a severe and rapidly-progressive course has never been described with disulfiram dosages of only 500mg/day. Copyright © 2016 Elsevier B.V. All rights reserved.

Electrical stimulation enhances sensory recovery: a randomized controlled trial.

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Wong, Joshua N; Olson, Jaret L; Morhart, Michael J; Chan, K Ming

2015-06-01

Brief postsurgical electrical stimulation (ES) has been shown to enhance peripheral nerve regeneration in animal models following axotomy and crush injury. However, whether this treatment is beneficial in humans with sensory nerve injury has not been tested. The goal of this study was to test the hypothesis that ES would enhance sensory nerve regeneration following digital nerve transection compared to surgery alone. Patients with complete digital nerve transection underwent epineurial nerve repair. After coaptation of the severed nerve ends, fine wire electrodes were implanted before skin closure. Postoperatively, patients were randomized to receiving either 1 hour of 20Hz continuous ES or sham stimulation in a double-blinded manner. Patients were followed monthly for 6 months by a blinded evaluator to monitor physiological recovery of spatial discrimination, pressure threshold, and quantitative small fiber sensory testing. Functional disability was measured using the Disability of Arm, Shoulder, and Hand questionnaire. A total of 36 patients were recruited, with 18 in each group. Those in the ES group showed consistently greater improvements in all sensory modalities by 5 to 6 months postoperatively compared to the controls. Although there was a trend of greater functional improvements in the ES group, it was not statistically significant (p > 0.01). Postsurgical ES enhanced sensory reinnervation in patients who sustained complete digital nerve transection. The conferred benefits apply to a wide range of sensory functions. © 2015 American Neurological Association.

Early sensory re-education of the hand after peripheral nerve repair based on mirror therapy: a randomized controlled trial

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Paula, Mayara H.; Barbosa, Rafael I.; Marcolino, Alexandre M.; Elui, Valéria M. C.; Rosén, Birgitta; Fonseca, Marisa C. R.

2016-01-01

BACKGROUND: Mirror therapy has been used as an alternative stimulus to feed the somatosensory cortex in an attempt to preserve hand cortical representation with better functional results. OBJECTIVE: To analyze the short-term functional outcome of an early re-education program using mirror therapy compared to a late classic sensory program for hand nerve repair. METHOD: This is a randomized controlled trial. We assessed 20 patients with median and ulnar nerve and flexor tendon repair using the Rosen Score combined with the DASH questionnaire. The early phase group using mirror therapy began on the first postoperative week and lasted 5 months. The control group received classic sensory re-education when the protective sensation threshold was restored. All participants received a patient education booklet and were submitted to the modified Duran protocol for flexor tendon repair. The assessments were performed by the same investigator blinded to the allocated treatment. Mann-Whitney Test and Effect Size using Cohen's d score were used for inter-group comparisons at 3 and 6 months after intervention. RESULTS: The primary outcome (Rosen score) values for the Mirror Therapy group and classic therapy control group after 3 and 6 months were 1.68 (SD=0.5); 1.96 (SD=0.56) and 1.65 (SD=0.52); 1.51 (SD=0.62), respectively. No between-group differences were observed. CONCLUSION: Although some clinical improvement was observed, mirror therapy was not shown to be more effective than late sensory re-education in an intermediate phase of nerve repair in the hand. Replication is needed to confirm these findings. PMID:26786080

Early sensory re-education of the hand after peripheral nerve repair based on mirror therapy: a randomized controlled trial

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Mayara H. Paula

2016-02-01

Full Text Available BACKGROUND: Mirror therapy has been used as an alternative stimulus to feed the somatosensory cortex in an attempt to preserve hand cortical representation with better functional results. OBJECTIVE: To analyze the short-term functional outcome of an early re-education program using mirror therapy compared to a late classic sensory program for hand nerve repair. METHOD: This is a randomized controlled trial. We assessed 20 patients with median and ulnar nerve and flexor tendon repair using the Rosen Score combined with the DASH questionnaire. The early phase group using mirror therapy began on the first postoperative week and lasted 5 months. The control group received classic sensory re-education when the protective sensation threshold was restored. All participants received a patient education booklet and were submitted to the modified Duran protocol for flexor tendon repair. The assessments were performed by the same investigator blinded to the allocated treatment. Mann-Whitney Test and Effect Size using Cohen's d score were used for inter-group comparisons at 3 and 6 months after intervention. RESULTS: The primary outcome (Rosen score values for the Mirror Therapy group and classic therapy control group after 3 and 6 months were 1.68 (SD=0.5; 1.96 (SD=0.56 and 1.65 (SD=0.52; 1.51 (SD=0.62, respectively. No between-group differences were observed. CONCLUSION: Although some clinical improvement was observed, mirror therapy was not shown to be more effective than late sensory re-education in an intermediate phase of nerve repair in the hand. Replication is needed to confirm these findings.

Grapefruit-seed extract attenuates ethanol-and stress-induced gastric lesions via activation of prostaglandin, nitric oxide and sensory nerve pathways.

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Brzozowski, Tomasz; Konturek, Peter C; Drozdowicz, Danuta; Konturek, Stanislaw J; Zayachivska, Oxana; Pajdo, Robert; Kwiecien, Slawomir; Pawlik, Wieslaw W; Hahn, Eckhart G

2005-11-07

Grapefruit-seed extract (GSE) containing flavonoids, possesses antibacterial and antioxidative properties but whether it influences the gastric defense mechanism and gastroprotection against ethanol- and stress-induced gastric lesions remains unknown. We compared the effects of GSE on gastric mucosal lesions induced in rats by topical application of 100% ethanol or 3.5 h of water immersion and restraint stress (WRS) with or without (A) inhibition of cyclooxygenase (COX)-1 activity by indomethacin and rofecoxib, the selective COX-2 inhibitor, (B) suppression of NO-synthase with L-NNA (20 mg/kg ip), and (C) inactivation by capsaicin (125 mg/kg sc) of sensory nerves with or without intragastric (ig) pretreatment with GSE applied 30 min prior to ethanol or WRS. One hour after ethanol and 3.5 h after the end of WRS, the number and area of gastric lesions were measured by planimetry, the gastric blood flow (GBF) was assessed by H2-gas clearance technique and plasma gastrin levels and the gastric mucosal generation of PGE2, superoxide dismutase (SOD) activity and malonyldialdehyde (MDA) concentration, as an index of lipid peroxidation were determined. Ethanol and WRS caused gastric lesions accompanied by the significant fall in the GBF and SOD activity and the rise in the mucosal MDA content. Pretreatment with GSE (8-64 mg/kg i g) dose-dependently attenuated gastric lesions induced by 100% ethanol and WRS; the dose reducing these lesions by 50% (ID50) was 25 and 36 mg/kg, respectively, and this protective effect was similar to that obtained with methyl PGE2 analog (5 microg/kg i g). GSE significantly raised the GBF, mucosal generation of PGE2, SOD activity and plasma gastrin levels while attenuating MDA content. Inhibition of PGE2 generation with indomethacin or rofecoxib and suppression of NO synthase by L-NNA or capsaicin denervation reversed the GSE-induced protection and the accompanying hyperemia. Co-treatment of exogenous calcitonine gene-related peptide (CGRP) with

A pilot study of sensory feedback by transcutaneous electrical nerve stimulation to improve manipulation deficit caused by severe sensory loss after stroke.

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Kita, Kahori; Otaka, Yohei; Takeda, Kotaro; Sakata, Sachiko; Ushiba, Junichi; Kondo, Kunitsugu; Liu, Meigen; Osu, Rieko

2013-06-13

Sensory disturbance is common following stroke and can exacerbate functional deficits, even in patients with relatively good motor function. In particular, loss of appropriate sensory feedback in severe sensory loss impairs manipulation capability. We hypothesized that task-oriented training with sensory feedback assistance would improve manipulation capability even without sensory pathway recovery. We developed a system that provides sensory feedback by transcutaneous electrical nerve stimulation (SENS) for patients with sensory loss, and investigated the feasibility of the system in a stroke patient with severe sensory impairment and mild motor deficit. The electrical current was modulated by the force exerted by the fingertips so as to allow the patient to identify the intensity. The patient had severe sensory loss due to a right thalamic hemorrhage suffered 27 months prior to participation in the study. The patient first practiced a cylindrical grasp task with SENS for 1 hour daily over 29 days. Pressure information from the affected thumb was fed back to the unaffected shoulder. The same patient practiced a tip pinch task with SENS for 1 hour daily over 4 days. Pressure information from the affected thumb and index finger was fed back to the unaffected and affected shoulders, respectively. We assessed the feasibility of SENS and examined the improvement of manipulation capability after training with SENS. The fluctuation in fingertip force during the cylindrical grasp task gradually decreased as the training progressed. The patient was able to maintain a stable grip force after training, even without SENS. Pressure exerted by the tip pinch of the affected hand was unstable before intervention with SENS compared with that of the unaffected hand. However, they were similar to each other immediately after SENS was initiated, suggesting that the somatosensory information improved tip pinch performance. The patient's manipulation capability assessed by the Box

Axon-Sorting Multifunctional Nerve Guides: Accelerating Restoration of Nerve Function

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2014-10-01

factor (singly & in selected combinations) in the organotypic model system for preferential sensory or motor axon extension. Use confocal microscopy to...track axon extension of labeled sensory or motor neurons from spinal cord slices (motor) or dorsal root ganglia ( DRG ) (sensory). 20 Thy1-YFP mice...RESEARCH ACCOMPLISHMENTS: • Established a system of color-coded mixed nerve tracking using GFP and RFP expressing motor and sensory neurons (Figure 1

End-to-side nerve suture – a technique to repair peripheral nerve ...

African Journals Online (AJOL)

Lateral sprouting from an intact nerve into an attached nerve does occur, and functional recovery (sensory and motor) has been demonstrated. We have demonstrated conclusively that ETSNS in the human is a viable option in treating peripheral nerve injuries, including injuries to the brachial plexus. Among the many ...

Comparison of oxime reactivation and aging of nerve agent-inhibited monkey and human acetylcholinesterases.

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Luo, Chunyuan; Tong, Min; Maxwell, Donald M; Saxena, Ashima

2008-09-25

Non-human primates are valuable animal models that are used for the evaluation of nerve agent toxicity as well as antidotes and results from animal experiments are extrapolated to humans. It has been demonstrated that the efficacy of an oxime primarily depends on its ability to reactivate nerve agent-inhibited acetylcholinesterase (AChE). If the in vitro oxime reactivation of nerve agent-inhibited animal AChE is similar to that of human AChE, it is likely that the results of an in vivo animal study will reliably extrapolate to humans. Therefore, the goal of this study was to compare the aging and reactivation of human and different monkey (Rhesus, Cynomolgus, and African Green) AChEs inhibited by GF, GD, and VR. The oximes examined include the traditional oxime 2-PAM, two H-oximes HI-6 and HLo-7, and the new candidate oxime MMB4. Results indicate that oxime reactivation of all three monkey AChEs was very similar to human AChE. The maximum difference in the second-order reactivation rate constant between human and three monkey AChEs or between AChEs from different monkey species was 5-fold. Aging rate constants of GF-, GD-, and VR-inhibited monkey AChEs were very similar to human AChE except for GF-inhibited monkey AChEs, which aged 2-3 times faster than the human enzyme. The results of this study suggest that all three monkey species are suitable animal models for nerve agent antidote evaluation since monkey AChEs possess similar biochemical/pharmacological properties to human AChE.

Progranulin overexpression in sensory neurons attenuates neuropathic pain in mice: Role of autophagy.

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Altmann, Christine; Hardt, Stefanie; Fischer, Caroline; Heidler, Juliana; Lim, Hee-Young; Häussler, Annett; Albuquerque, Boris; Zimmer, Béla; Möser, Christine; Behrends, Christian; Koentgen, Frank; Wittig, Ilka; Schmidt, Mirko H H; Clement, Albrecht M; Deller, Thomas; Tegeder, Irmgard

2016-12-01

Peripheral or central nerve injury is a frequent cause of chronic pain and the mechanisms are not fully understood. Using newly generated transgenic mice we show that progranulin overexpression in sensory neurons attenuates neuropathic pain after sciatic nerve injury and accelerates nerve healing. A yeast-2-hybrid screen revealed putative interactions of progranulin with autophagy-related proteins, ATG12 and ATG4b. This was supported by colocalization and proteomic studies showing regulations of ATG13 and ATG4b and other members of the autophagy network, lysosomal proteins and proteins involved in endocytosis. The association of progranulin with the autophagic pathway was functionally confirmed in primary sensory neurons. Autophagy and survival were impaired in progranulin-deficient neurons and improved in progranulin overexpressing neurons. Nerve injury in vivo caused an accumulation of LC3b-EGFP positive bodies in neurons of the dorsal root ganglia and nerves suggesting an impairment of autophagic flux. Overexpression of progranulin in these neurons was associated with a reduction of the stress marker ATF3, fewer protein aggregates in the injured nerve and enhanced stump healing. At the behavioral level, further inhibition of the autophagic flux by hydroxychloroquine intensified cold and heat nociception after sciatic nerve injury and offset the pain protection provided by progranulin. We infer that progranulin may assist in removal of protein waste and thereby helps to resolve neuropathic pain after nerve injury. Copyright © 2016 Elsevier Inc. All rights reserved.

Vagus nerve stimulation paired with tactile training improved sensory function in a chronic stroke patient.

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Kilgard, Michael P; Rennaker, Robert L; Alexander, Jen; Dawson, Jesse

2018-01-01

Recent studies indicate that vagus nerve stimulation (VNS) paired with rehabilitation can enhance neural plasticity in the primary sensory and motor cortices, improve forelimb function after stroke in animal models and improve motor function in patients with arm weakness after stroke. To gain "first-in-man" experience of VNS paired with tactile training in a patient with severe sensory impairment after stroke. During the long-term follow-up phase of a clinical trial of VNS paired with motor rehabilitation, a 71-year-old man who had made good motor recovery had ongoing severe sensory loss in his left hand and arm. He received VNS paired with tactile therapy in an attempt to improve his sensory function. During twenty 2-hour sessions, each passive and active tactile event was paired with a 0.5 second burst of 0.8 mA VNS. Sensory function was measured before, halfway through, and after this therapy. The patient did not report any side effects during or following VNS+Tactile therapy. Quantitative measures revealed lasting and clinically meaningful improvements in tactile threshold, proprioception, and stereognosis. After VNS+Tactile therapy, the patient was able to detect tactile stimulation to his affected hand that was eight times less intense, identify the joint position of his fingers in the affected hand three times more often, and identify everyday objects using his affected hand seven times more often, compared to baseline. Sensory function significantly improved in this man following VNS paired with tactile stimulation. This approach merits further study in controlled clinical trials.

Uncovering sensory axonal dysfunction in asymptomatic type 2 diabetic neuropathy.

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Jia-Ying Sung

Full Text Available This study investigated sensory and motor nerve excitability properties to elucidate the development of diabetic neuropathy. A total of 109 type 2 diabetes patients were recruited, and 106 were analyzed. According to neuropathy severity, patients were categorized into G0, G1, and G2+3 groups using the total neuropathy score-reduced (TNSr. Patients in the G0 group were asymptomatic and had a TNSr score of 0. Sensory and motor nerve excitability data from diabetic patients were compared with data from 33 healthy controls. Clinical assessment, nerve conduction studies, and sensory and motor nerve excitability testing data were analyzed to determine axonal dysfunction in diabetic neuropathy. In the G0 group, sensory excitability testing revealed increased stimulus for the 50% sensory nerve action potential (P<0.05, shortened strength-duration time constant (P<0.01, increased superexcitability (P<0.01, decreased subexcitability (P<0.05, decreased accommodation to depolarizing current (P<0.01, and a trend of decreased accommodation to hyperpolarizing current in threshold electrotonus. All the changes progressed into G1 (TNSr 1-8 and G2+3 (TNSr 9-24 groups. In contrast, motor excitability only had significantly increased stimulus for the 50% compound motor nerve action potential (P<0.01 in the G0 group. This study revealed that the development of axonal dysfunction in sensory axons occurred prior to and in a different fashion from motor axons. Additionally, sensory nerve excitability tests can detect axonal dysfunction even in asymptomatic patients. These insights further our understanding of diabetic neuropathy and enable the early detection of sensory axonal abnormalities, which may provide a basis for neuroprotective therapeutic approaches.

Diabetic neuropathy: structural analysis of nerve hydration by Magnetic Resonance Spectroscopy

International Nuclear Information System (INIS)

Griffey, R.H.; Eaton, P.; Sibbitt, R.R.; Sibbitt, W.L. Jr.; Bicknell, J.M.

1988-01-01

The water content of the sural nerve of diabetic patients was quantitatively defined by magnetic resonance proton imaging as a putative reflection of activity of the aldose-reductase pathway. Thirty-nine patients were evaluated, comparing group A, symptomatic diabetic men with sensory neuropathy; group B, similarly symptomatic diabetic men treated aldose-reductase inhibition; group C, neurologically asymptomatic diabetic men; and group D, control nondiabetic men. Marked increase in hydration of the sural nerve was seen in more than half of the symptomatic diabetic patients. Two of 11 neurologically asymptomatic diabetics had increased nerve hydration, suggesting a presymptomatic alteration of the nerve. Symptomatic diabetics treated with aldose-reductase inhibitors had normal nerve water levels. Increased level of peripheral nerve water represents a new finding in diabetes mellitus. It seems to be related to aldose-reductase activity, involved in the development of neuropathy, and similar to events that occur in other target tissue in human diabetes

Inhibition by TRPA1 agonists of compound action potentials in the frog sciatic nerve

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Matsushita, Akitomo; Ohtsubo, Sena; Fujita, Tsugumi; Kumamoto, Eiichi, E-mail: kumamote@cc.saga-u.ac.jp

2013-04-26

Highlights: •TRPA1 agonists inhibited compound action potentials in frog sciatic nerves. •This inhibition was not mediated by TRPA1 channels. •This efficacy was comparable to those of lidocaine and cocaine. •We found for the first time an ability of TRPA1 agonists to inhibit nerve conduction. -- Abstract: Although TRPV1 and TRPM8 agonists (vanilloid capsaicin and menthol, respectively) at high concentrations inhibit action potential conduction, it remains to be unknown whether TRPA1 agonists have a similar action. The present study examined the actions of TRPA1 agonists, cinnamaldehyde (CA) and allyl isothiocyanate (AITC), which differ in chemical structure from each other, on compound action potentials (CAPs) recorded from the frog sciatic nerve by using the air-gap method. CA and AITC concentration-dependently reduced the peak amplitude of the CAP with the IC{sub 50} values of 1.2 and 1.5 mM, respectively; these activities were resistant to a non-selective TRP antagonist ruthenium red or a selective TRPA1 antagonist HC-030031. The CA and AITC actions were distinct in property; the latter but not former action was delayed in onset and partially reversible, and CA but not AITC increased thresholds to elicit CAPs. A CAP inhibition was seen by hydroxy-α-sanshool (by 60% at 0.05 mM), which activates both TRPA1 and TRPV1 channels, a non-vanilloid TRPV1 agonist piperine (by 20% at 0.07 mM) and tetrahydrolavandulol (where the six-membered ring of menthol is opened; IC{sub 50} = 0.38 mM). It is suggested that TRPA1 agonists as well as TRPV1 and TRPM8 agonists have an ability to inhibit nerve conduction without TRP activation, although their agonists are quite different in chemical structure from each other.

Anterograde transneuronal viral tract tracing reveals central sensory circuits from brown fat and sensory denervation alters its thermogenic responses.

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Vaughan, Cheryl H; Bartness, Timothy J

2012-05-01

Brown adipose tissue (BAT) thermogenic activity and growth are controlled by its sympathetic nervous system (SNS) innervation, but nerve fibers containing sensory-associated neuropeptides [substance P, calcitonin gene-related peptide (CGRP)] also suggest sensory innervation. The central nervous system (CNS) projections of BAT afferents are unknown. Therefore, we used the H129 strain of the herpes simplex virus-1 (HSV-1), an anterograde transneuronal viral tract tracer used to delineate sensory nerve circuits, to define these projections. HSV-1 was injected into interscapular BAT (IBAT) of Siberian hamsters and HSV-1 immunoreactivity (ir) was assessed 24, 48, 72, 96, and 114 h postinjection. The 96- and 114-h groups had the most HSV-1-ir neurons with marked infections in the hypothalamic paraventricular nucleus, periaqueductal gray, olivary areas, parabrachial nuclei, raphe nuclei, and reticular areas. These sites also are involved in sympathetic outflow to BAT suggesting possible BAT sensory-SNS thermogenesis feedback circuits. We tested the functional contribution of IBAT sensory innervation on thermogenic responses to an acute (24 h) cold exposure test by injecting the specific sensory nerve toxin capsaicin directly into IBAT pads and then measuring core (T(c)) and IBAT (T(IBAT)) temperature responses. CGRP content was significantly decreased in capsaicin-treated IBAT demonstrating successful sensory nerve destruction. T(IBAT) and T(c) were significantly decreased in capsaicin-treated hamsters compared with the saline controls at 2 h of cold exposure. Thus the central sensory circuits from IBAT have been delineated for the first time, and impairment of sensory feedback from BAT appears necessary for the appropriate, initial thermogenic response to acute cold exposure.

Maximizing the effect of an α7 nicotinic receptor PAM in a mouse model of schizophrenia-like sensory inhibition deficits.

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Stevens, Karen E; Zheng, Lijun; Floyd, Kirsten L; Stitzel, Jerry A

2015-06-22

Positive allosteric modulators (PAMs) for the α7 nicotinic receptor hold promise for the treatment of sensory inhibition deficits observed in schizophrenia patients. Studies of these compounds in the DBA/2 mouse, which models the schizophrenia-related deficit in sensory inhibition, have shown PAMs to be effective in improving the deficit. However, the first published clinical trial of a PAM for both sensory inhibition deficits and related cognitive difficulties failed, casting a shadow on this therapeutic approach. The present study used both DBA/2 mice, and C3H Chrna7 heterozygote mice to assess the ability of the α7 PAM, PNU-120596, to improve sensory inhibition. Both of these strains of mice have reduced hippocampal α7 nicotinic receptor numbers and deficient sensory inhibition similar to schizophrenia patients. Low doses of PNU-120596 (1 or 3.33mg/kg) were effective in the DBA/2 mouse but not the C3H Chrna7 heterozygote mouse. Moderate doses of the selective α7 nicotinic receptor agonist, choline chloride (10 or 33mg/kg), were also ineffective in improving sensory inhibition in the C3H Chrna7 heterozygote mouse. However, combining the lowest doses of both PNU-120596 and choline chloride in this mouse model did improve sensory inhibition. We propose here that the difference in efficacy of PNU-120596 between the 2 mouse strains is driven by differences in hippocampal α7 nicotinic receptor numbers, such that C3H Chrna7 heterozygote mice require additional direct stimulation of the α7 receptors. These data may have implications for further clinical testing of putative α7 nicotinic receptor PAMs. Copyright © 2015 Elsevier B.V. All rights reserved.

Uptake of 3H-thymidine by the receptor cell populations after injury of the sensory nerve fibres

International Nuclear Information System (INIS)

Chuchkov, Ch.N.

1978-01-01

The material of the study was the skin from the beak of two-day ducklings. The investigation was carried out on the 2nd, 5th, 20th and 45th day after the crushing of the sensory nerve fibres entering the capsulated Herbst receptors. Twenty four hours before the biopsy, the ducklings were injected at 6 hours intervals with 3 H-thymidine. The number of labelled index in the three cell pupulations, participating in the receptor development was determined. The cells of the subcapsular space of all control animals (with intacted suborbital nerves) have shown the highest labelled index. The index of the capsular perineural cells is about 12 times lower, while the labelled index of the Schwann receptor cells is about 10 times lower. Following the denervation, the labelled index in increasing and reaches its maximum on the 5th postoperative day. The Schwann receptor cells in comparison to the two other cell populations show the most significant deviation during the regeneration (45th day after the intervention). The investigations show that all three cell populations pass through a miotic cycle of innovation. The low labelled index of the Schwann receptors (1-2 labelled cells in 1000) is an indication of a high differentiation. One can assume that their regeneration takes place at the expense of the proper proliferation activity as well as of the differentiation of the Schwann cells from the distal section of the regenerating sensory nerve fibres. Taking into consideration the high labelled index of the other populations, it seems most probable that their regeneration takes place for the expense of their own cell populations. (A.B.)

Clinical neurophysiology and quantitative sensory testing in the investigation of orofacial pain and sensory function.

Science.gov (United States)

Jääskeläinen, Satu K

2004-01-01

Chronic orofacial pain represents a diagnostic and treatment challenge for the clinician. Some conditions, such as atypical facial pain, still lack proper diagnostic criteria, and their etiology is not known. The recent development of neurophysiological methods and quantitative sensory testing for the examination of the trigeminal somatosensory system offers several tools for diagnostic and etiological investigation of orofacial pain. This review presents some of these techniques and the results of their application in studies on orofacial pain and sensory dysfunction. Clinical neurophysiological investigation has greater diagnostic accuracy and sensitivity than clinical examination in the detection of the neurogenic abnormalities of either peripheral or central origin that may underlie symptoms of orofacial pain and sensory dysfunction. Neurophysiological testing may also reveal trigeminal pathology when magnetic resonance imaging has failed to detect it, so these methods should be considered complementary to each other in the investigation of orofacial pain patients. The blink reflex, corneal reflex, jaw jerk, sensory neurography of the inferior alveolar nerve, and the recording of trigeminal somatosensory-evoked potentials with near-nerve stimulation have all proved to be sensitive and reliable in the detection of dysfunction of the myelinated sensory fibers of the trigeminal nerve or its central connections within the brainstem. With appropriately small thermodes, thermal quantitative sensory testing is useful for the detection of trigeminal small-fiber dysfunction (Adelta and C). In neuropathic conditions, it is most sensitive to lesions causing axonal injury. By combining different techniques for investigation of the trigeminal system, an accurate topographical diagnosis and profile of sensory fiber pathology can be determined. Neurophysiological and quantitative sensory tests have already highlighted some similarities among various orofacial pain conditions

Cell-type specific short-term plasticity at auditory nerve synapses controls feed-forward inhibition in the dorsal cochlear nucleus

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Miloslav eSedlacek

2014-07-01

Full Text Available Feedforward inhibition represents a powerful mechanism by which control of the timing and fidelity of action potentials in local synaptic circuits of various brain regions is achieved. In the cochlear nucleus, the auditory nerve provides excitation to both principal neurons and inhibitory interneurons. Here, we investigated the synaptic circuit associated with fusiform cells (FCs, principal neurons of the dorsal cochlear nucleus (DCN that receive excitation from auditory nerve fibers and inhibition from tuberculoventral cells (TVCs on their basal dendrites in the deep layer of DCN. Despite the importance of these inputs in regulating fusiform cell firing behavior, the mechanisms determining the balance of excitation and feed-forward inhibition in this circuit are not well understood. Therefore, we examined the timing and plasticity of auditory nerve driven feed-forward inhibition (FFI onto FCs. We find that in some FCs, excitatory and inhibitory components of feed-forward inhibition had the same stimulation thresholds indicating they could be triggered by activation of the same fibers. In other FCs, excitation and inhibition exhibit different stimulus thresholds, suggesting FCs and TVCs might be activated by different sets of fibers. In addition we find that during repetitive activation, synapses formed by the auditory nerve onto TVCs and FCs exhibit distinct modes of short-term plasticity. Feed-forward inhibitory post-synaptic currents (IPSCs in FCs exhibit short-term depression because of prominent synaptic depression at the auditory nerve-TVC synapse. Depression of this feedforward inhibitory input causes a shift in the balance of fusiform cell synaptic input towards greater excitation and suggests that fusiform cell spike output will be enhanced by physiological patterns of auditory nerve activity.

Inhibition of micturition reflex by activation of somatic afferents in posterior femoral cutaneous nerve.

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Tai, Changfeng; Shen, Bing; Mally, Abhijith D; Zhang, Fan; Zhao, Shouguo; Wang, Jicheng; Roppolo, James R; de Groat, William C

2012-10-01

This study determined if activation of somatic afferents in posterior femoral cutaneous nerve (PFCN) could modulate the micturition reflex recorded under isovolumetric conditions in α-chloralose anaesthetized cats. PFCN stimulation inhibited reflex bladder activity and significantly (P acid (AA). The optimal frequency for PFCN stimulation-induced bladder inhibition was between 3 and 10 Hz, and a minimal stimulation intensity of half of the threshold for inducing anal twitching was required. Bilateral pudendal nerve transection eliminated PFCN stimulation-induced anal twitching but did not change the stimulation-induced bladder inhibition, excluding the involvement of pudendal afferent or efferent axons in PFCN afferent inhibition.Mechanical or electrical stimulation on the skin surface in the PFCN dermatome also inhibited bladder activity. Prolonged (2 × 30 min) PFCN stimulation induced a post-stimulation inhibition that persists for at least 2 h. This study revealed a new cutaneous-bladder reflex activated by PFCN afferents. Although the mechanisms and physiological functions of this cutaneous-bladder reflex need to be further studied, our data raise the possibility that stimulation of PFCN afferents might be useful clinically for the treatment of overactive bladder symptoms.

Which Ultrasound-Guided Sciatic Nerve Block Strategy Works Faster? Prebifurcation or Separate Tibial-Peroneal Nerve Block? A Randomized Clinical Trial.

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Faiz, Seyed Hamid Reza; Imani, Farnad; Rahimzadeh, Poupak; Alebouyeh, Mahmoud Reza; Entezary, Saeed Reza; Shafeinia, Amineh

2017-08-01

Peripheral nerve block is an accepted method in lower limb surgeries regarding its convenience and good tolerance by the patients. Quick performance and fast sensory and motor block are highly demanded in this method. The aim of the present study was to compare 2 different methods of sciatic and tibial-peroneal nerve block in lower limb surgeries in terms of block onset. In this clinical trial, 52 candidates for elective lower limb surgery were randomly divided into 2 groups: sciatic nerve block before bifurcation (SG; n = 27) and separate tibial-peroneal nerve block (TPG; n = 25) under ultrasound plus nerve stimulator guidance. The mean duration of block performance, as well as complete sensory and motor block, was recorded and compared between the groups. The mean duration of complete sensory block in the SG and TPG groups was 35.4 ± 4.1 and 24.9 ± 4.2 minutes, respectively, which was significantly lower in the TPG group (P = 0.001). The mean duration of complete motor block in the SG and TPG groups was 63.3 ± 4.4 and 48.4 ± 4.6 minutes, respectively, which was significantly lower in the TPG group (P = 0.001). No nerve injuries, paresthesia, or other possible side effects were reported in patients. According to the present study, it seems that TPG shows a faster sensory and motor block than SG.

From genes to pain: nerve growth factor and hereditary sensory and autonomic neuropathy type V.

Science.gov (United States)

Capsoni, Simona

2014-02-01

Hereditary sensory and autonomic neuropathy type V (HSAN V) is an autosomal recessive disorder characterized by the loss of deep pain perception. The anomalous pain and temperature sensations are due to the absence of nociceptive sensory innervation. The neurotrophin nerve growth factor (NGF), by binding to tropomyosin receptor A (TrkA) and p75NTR receptors, is essential for the development and survival of sensory neurons, and for pain perception during adulthood. Recently a homozygous missense mutation (R100W) in the NGF gene has been identified in HSAN V patients. Interestingly, alterations in NGF signalling, due to mutations in the NGF TRKA gene, have also been involved in another congenital insensitivity to pain, HSAN IV, characterized not only by absence of reaction to painful stimuli, but also anhidrosis and mental retardation. These symptoms are absent in HSAN V patients. Unravelling the mechanisms that underlie the differences between HSAN IV and V could assist in better understanding NGF biology. This review highlights the recent key findings in the understanding of HSAN V, including insights into the molecular mechanisms of the disease, derived from genetic studies of patients with this disorder. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Genetics Home Reference: hereditary sensory neuropathy type IA

Science.gov (United States)

... sensory neuropathy type IA Hereditary sensory neuropathy type IA Printable PDF Open All Close All Enable Javascript ... expand/collapse boxes. Description Hereditary sensory neuropathy type IA is a condition characterized by nerve abnormalities in ...

Evaluation of functional nerve recovery after reconstruction with a new biodegradable poly (DL-lactide-epsilon-caprolactone) nerve guide

NARCIS (Netherlands)

Meek, MF; denDunnen, WFA; Robinson, PH; Pennings, AJ; Schakenraad, JM

The aim of this study was to evaluate functional nerve recovery following reconstruction of a 1 cm gap in the sciatic nerve of a rat, using a new biodegradable p (DLLA-epsilon-CL) nerve guide. To evaluate both motor and sensory nerve recovery, walking track analysis and electrostimulation tests were

A preconditioning nerve lesion inhibits mechanical pain hypersensitivity following subsequent neuropathic injury

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Wu Ann

2011-01-01

Full Text Available Abstract Background A preconditioning stimulus can trigger a neuroprotective phenotype in the nervous system - a preconditioning nerve lesion causes a significant increase in axonal regeneration, and cerebral preconditioning protects against subsequent ischemia. We hypothesized that a preconditioning nerve lesion induces gene/protein modifications, neuronal changes, and immune activation that may affect pain sensation following subsequent nerve injury. We examined whether a preconditioning lesion affects neuropathic pain and neuroinflammation after peripheral nerve injury. Results We found that a preconditioning crush injury to a terminal branch of the sciatic nerve seven days before partial ligation of the sciatic nerve (PSNL; a model of neuropathic pain induced a significant attenuation of pain hypersensitivity, particularly mechanical allodynia. A preconditioning lesion of the tibial nerve induced a long-term significant increase in paw-withdrawal threshold to mechanical stimuli and paw-withdrawal latency to thermal stimuli, after PSNL. A preconditioning lesion of the common peroneal induced a smaller but significant short-term increase in paw-withdrawal threshold to mechanical stimuli, after PSNL. There was no difference between preconditioned and unconditioned animals in neuronal damage and macrophage and T-cell infiltration into the dorsal root ganglia (DRGs or in astrocyte and microglia activation in the spinal dorsal and ventral horns. Conclusions These results suggest that prior exposure to a mild nerve lesion protects against adverse effects of subsequent neuropathic injury, and that this conditioning-induced inhibition of pain hypersensitivity is not dependent on neuroinflammation in DRGs and spinal cord. Identifying the underlying mechanisms may have important implications for the understanding of neuropathic pain due to nerve injury.

Morphology of nerve endings in vocal fold of human newborn.

Science.gov (United States)

Gonçalves da Silva Leite, Janaina; Costa Cavalcante, Maria Luzete; Fechine-Jamacaru, Francisco Vagnaldo; de Lima Pompeu, Margarida Maria; Leite, José Alberto Dias; Nascimento Coelho, Dulce Maria; Rabelo de Freitas, Marcos

2016-10-01

Sensory receptors are distributed throughout the oral cavity, pharynx, and larynx. Laryngeal sensitivity is crucial for maintaining safe swallowing, thus avoiding silent aspiration. Morphologic description of different receptor types present in larynx vary because of the study of many different species, from mouse to humans. The most commonly sensory structures described in laryngeal mucosa are free nerve endings, taste buds, muscle spindles, glomerular and corpuscular receptors. This study aimed at describing the morphology and the distribution of nerve endings in premature newborn glottic region. Transversal serial frozen sections of the whole vocal folds of three newborns were analyzed using an immuno-histochemical process with a pan-neuronal marker anti-protein gene product 9.5 (PGP 9.5). Imaging was done using a confocal laser microscope. Nerve fiber density in vocal cord was calculated using panoramic images in software Morphometric Analysis System v1.0. Some sensory structures, i.e. glomerular endings and intraepithelial free nerve endings were found in the vocal cord mucosa. Muscle spindles, complex nerve endings (Meissner-like, spherical, rectangular and growing) spiral-wharves nerve structures were identified in larynx intrinsic muscles. Nervous total mean density in vocal cord was similar in the three newborns, although they had different gestational age. The mean nerve fiber density was higher in the posterior region than anterior region of vocal cord. The present results demonstrate the occurrence of different morphotypes of sensory corpuscles and nerve endings premature newborn glottic region and provide information on their sensory systems. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

H-reflex amplitude depression as a marker of presynaptic inhibition in Painful Diabetic Neuropathy (PDN.

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Ahmad Asmedi

2016-02-01

Full Text Available ABSTRACT Painful Diabetic Neuropathy (PDN is a common complication of diabetes mellitus (DM. Disruption in presynaptic inhibition in dorsal horn of the spinal cord has been proposed as one of the pathomechanism of PDN. Previous research showed that presynaptic inhibition can be detected by H-reflex examination. The aim of this study was to know whether the reduction of presynaptic inhibition in spinal dorsal horn of PDN patients really exist, and detectable by H-reflex examination. It was cohort prospective involving 141 (58 men, 83 women patients with DM and impaired glucose tolerance (IGT between the ages of 40 and 61 years from several health facilities in Yogyakarta. All patients underwent clinical, laboratory and electrodiagnostic examination. Demographic, clinical and electrodiagnostic data were collected and analyzed. By survival analysis there were 25 new cases of PDN (12.12% cumulative incidence. Using survival Kaplan Meier analysis, the significant hazard ratio for PDN were 12.81 for median motor nerve amplitude, 5.74 for median nerve distal latency, 3.71 for median sensory nerve amplitude, 6.33 for median sensory latency, 3.4 for tibial nerve amplitude, 3.48 for tibial nerve distal latency, 2.29 for sural nerve amplitude, 4.47 for sural nerve latency, 3.99 for H-reflex latency, 5.88 for H-reflex amplitude, and 17.83 for Diabetic Neuropathy (DN status. Using hazard proportional cox analysis, only H amplitude and DN status (DNS score were significantly correlated with PDN (p= 0.026; hazard ratio = 15.450; CI 95%= 1.39 – 171.62 for H amplitude and p= 0.030; hazard ratio = 10.766; CI 95%=1.26 – 92.09 for DN status. This study showed that depression of H-reflex amplitude was correlated with the occurrence of PDN. This result proves that there was presynaptic inhibition process in PDN that manifests as low H-reflex amplitude.

Increased levels of SV2A botulinum neurotoxin receptor in clinical sensory disorders and functional effects of botulinum toxins A and E in cultured human sensory neurons

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Yiangou Y

2011-10-01

Full Text Available Yiangos Yiangou1 Uma Anand1,2, William R. Otto2, Marco Sinisi3, Michael Fox3, Rolfe Birch3 Keith A. Foster4, Gaurav Mukerji1,5, Ayesha Akbar1,6, Sanjiv K. Agarwal5, Praveen Anand11Department of Clinical Neuroscience, Imperial College London, Hammersmith Hospital, London; 2Histopathology Laboratory, Cancer Research UK, London Research Institute, London; 3Peripheral Nerve Injury Unit, Royal National Orthopaedic Hospital, Stanmore; 4Syntaxin Ltd, Oxford; 5Department of Urology; 6Department of Gastroenterology, Imperial College London, Hammersmith Hospital, London, United Kingdom Background: There is increasing evidence that botulinum neurotoxin A may affect sensory nociceptor fibers, but the expression of its receptors in clinical pain states, and its effects in human sensory neurons, are largely unknown.Methods: We studied synaptic vesicle protein subtype SV2A, a receptor for botulinum neurotoxin A, by immunostaining in a range of clinical tissues, including human dorsal root ganglion sensory neurons, peripheral nerves, the urinary bladder, and the colon. We also determined the effects of botulinum neurotoxins A and E on localization of the capsaicin receptor, TRPV1, and functional sensitivity to capsaicin stimuli in cultured human dorsal root ganglion neurons.Results: Image analysis showed that SV2A immunoreactive nerve fibers were increased in injured nerves proximal to the injury (P = 0.002, and in painful neuromas (P = 0.0027; the ratio of percentage area SV2A to neurofilaments (a structural marker was increased proximal to injury (P = 0.0022 and in neuromas (P = 0.0001, indicating increased SV2A levels in injured nerve fibers. In the urinary bladder, SV2A nerve fibers were found in detrusor muscle and associated with blood vessels, with a significant increase in idiopathic detrusor overactivity (P = 0.002 and painful bladder syndrome (P = 0.0087. Colon biopsies showed numerous SV2A-positive nerve fibers, which were increased in quiescent

Median Nerve Conduction in Healthy Nigerians: Normative Data

African Journals Online (AJOL)

of median nerve disease using multiple studies, and rendering ... Aim: To develop normative values for motor and sensory median nerve ..... Table 5: Comparison of median motor nerve conduction study parameters to studies elsewhere. Study.

Nerve ultrasound shows subclinical peripheral nerve involvement in neurofibromatosis type 2.

Science.gov (United States)

Telleman, Johan A; Stellingwerff, Menno D; Brekelmans, Geert J; Visser, Leo H

2018-02-01

Neurofibromatosis type 2 (NF2) is mainly associated with central nervous system (CNS) tumors. Peripheral nerve involvement is described in symptomatic patients, but evidence of subclinical peripheral nerve involvement is scarce. We conducted a cross-sectional pilot study in 2 asymptomatic and 3 minimally symptomatic patients with NF2 to detect subclinical peripheral nerve involvement. Patients underwent clinical examination, nerve conduction studies (NCS), and high-resolution ultrasonography (HRUS). A total of 30 schwannomas were found, divided over 20 nerve segments (33.9% of all investigated nerve segments). All patients had at least 1 schwannoma. Schwannomas were identified with HRUS in 37% of clinically unaffected nerve segments and 50% of nerve segments with normal NCS findings. HRUS shows frequent subclinical peripheral nerve involvement in NF2. Clinicians should consider peripheral nerve involvement as a cause of weakness and sensory loss in the extremities in patients with this disease. Muscle Nerve 57: 312-316, 2018. © 2017 Wiley Periodicals, Inc.

Electrophysiology of Cranial Nerve Testing: Cranial Nerves IX and X.

Science.gov (United States)

Martinez, Alberto R M; Martins, Melina P; Moreira, Ana Lucila; Martins, Carlos R; Kimaid, Paulo A T; França, Marcondes C

2018-01-01

The cranial nerves IX and X emerge from medulla oblongata and have motor, sensory, and parasympathetic functions. Some of these are amenable to neurophysiological assessment. It is often hard to separate the individual contribution of each nerve; in fact, some of the techniques are indeed a composite functional measure of both nerves. The main methods are the evaluation of the swallowing function (combined IX and X), laryngeal electromyogram (predominant motor vagal function), and heart rate variability (predominant parasympathetic vagal function). This review describes, therefore, the techniques that best evaluate the major symptoms presented in IX and X cranial nerve disturbance: dysphagia, dysphonia, and autonomic parasympathetic dysfunction.

Vagus nerve is involved in the changes in body temperature induced by intragastric administration of 1,8-cineole via TRPM8 in mice.

Science.gov (United States)

Urata, Tomomi; Mori, Noriyuki; Fukuwatari, Tsutomu

2017-05-22

Transient Receptor Potential Melastatin 8 (TRPM8) is a cold receptor activated by mild cold temperature (<28°C). TRPM8 expressed in cutaneous sensory nerves is involved in cold sensation and thermoregulation. TRPM8 mRNA is detected in various tissues, including the gastrointestinal mucosa, and in the vagal afferent nerve. The relationship between vagal afferent nerve-specific expression of TRPM8 and thermoregulation remains unclear. In this study, we aimed to investigate whether TRPM8 expression in the vagal afferent nerve is involved in autonomic thermoregulation. We found that intragastric administration of 1,8-cineole, a TRPM8 agonist, increased intrascapular brown adipose tissue and colonic temperatures, and M8-B-treatment (TRPM8 antagonist) inhibited these responses. Intravenous administration of 1,8-cineole also showed similar effects. In vagotomized mice, the responses induced by intragastric administration of 1,8-cineole were attenuated. These results suggest that TRPM8 expressed in tissues apart from cutaneous sensory nerves are involved in autonomic thermoregulation response. Copyright © 2017 Elsevier B.V. All rights reserved.

Indomethacin lowers optic nerve oxygen tension and reduces the effect of carbonic anhydrase inhibition and carbon dioxide breathing

DEFF Research Database (Denmark)

Pedersen, D B; Eysteinsson, T; Stefánsson, E

2004-01-01

Prostaglandins are important in blood flow regulation. Carbon dioxide (CO(2)) breathing and carbonic anhydrase inhibition increase the oxygen tension in the retina and optic nerve. To study the mechanism of this effect and the role of cyclo-oxygenase in the regulation of optic nerve oxygen tension...... (ONPO(2)), the authors investigated how indomethacin affects ONPO(2) and the ONPO(2) increases caused by CO(2) breathing and carbonic anhydrase inhibition in the pig....

Breast Reinnervation: DIEP Neurotization Using the Third Anterior Intercostal Nerve

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Aldona J. Spiegel, MD

2013-11-01

Conclusion: DIEP flap neurotization using the third anterior intercostal nerve is an effective technique to provide a significant increase in sensory recovery for breast reconstruction patients, while adding minimal surgical time. Additionally, the use of a nerve conduit produces increased sensory recovery when compared direct coaptation.

Retrograde tracing and toe spreading after experimental autologous nerve transplantation and crush injury of the sciatic nerve: a descriptive methodological study

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van Neerven Sabien GA

2012-04-01

Full Text Available Abstract Evaluation of functional and structural recovery after peripheral nerve injury is crucial to determine the therapeutic effect of a nerve repair strategy. In the present study, we examined the relationship between the structural evaluation of regeneration by means of retrograde tracing and the functional analysis of toe spreading. Two standardized rat sciatic nerve injury models were used to address this relationship. As such, animals received either a 2 cm sciatic nerve defect (neurotmesis followed by autologous nerve transplantation (ANT animals or a crush injury with spontaneous recovery (axonotmesis; CI animals. Functional recovery of toe spreading was observed over an observation period of 84 days. In contrast to CI animals, ANT animals did not reach pre-surgical levels of toe spreading. After the observation period, the lipophilic dye DiI was applied to label sensory and motor neurons in dorsal root ganglia (DRG; sensory neurons and spinal cord (motor neurons, respectively. No statistical difference in motor or sensory neuron counts could be detected between ANT and CI animals. In the present study we could indicate that there was no direct relationship between functional recovery (toe spreading measured by SSI and the number of labelled (motor and sensory neurons evaluated by retrograde tracing. The present findings demonstrate that a multimodal approach with a variety of independent evaluation tools is essential to understand and estimate the therapeutic benefit of a nerve repair strategy.

Vagus nerve stimulation inhibits activation of coagulation and fibrinolysis during endotoxemia in rats

NARCIS (Netherlands)

van Westerloo, D. J.; Giebelen, I. A. J.; Meijers, J. C. M.; Daalhuisen, J.; de Vos, A. F.; Levi, M. [=Marcel M.; van der Poll, T.

2006-01-01

BACKGROUND: Sepsis and endotoxemia are associated with concurrent activation of inflammation and the hemostatic mechanism, which both contribute to organ dysfunction and death. Electrical vagus nerve stimulation (VNS) has been found to inhibit tumor necrosis factor (TNF)-alpha release during

Early postnatal development of electrophysiological and histological properties of sensory sural nerves in male rats that were maternally deprived and artificially reared: Role of tactile stimulation.

Science.gov (United States)

Zempoalteca, Rene; Porras, Mercedes G; Moreno-Pérez, Suelem; Ramirez-Funez, Gabriela; Aguirre-Benítez, Elsa L; González Del Pliego, Margarita; Mariscal-Tovar, Silvia; Mendoza-Garrido, Maria E; Hoffman, Kurt Leroy; Jiménez-Estrada, Ismael; Melo, Angel I

2018-04-01

Early adverse experiences disrupt brain development and behavior, but little is known about how such experiences impact on the development of the peripheral nervous system. Recently, we found alterations in the electrophysiological and histological characteristics of the sensory sural (SU) nerve in maternally deprived, artificially reared (AR) adult male rats, as compared with maternally reared (MR) control rats. In the present study, our aim was to characterize the ontogeny of these alterations. Thus, male pups of four postnatal days (PND) were (1) AR group, (2) AR and received daily tactile stimulation to the body and anogenital region (AR-Tactile group); or (3) reared by their mother (MR group). At PND 7, 14, or 21, electrophysiological properties and histological characteristics of the SU nerves were assessed. At PND 7, the electrophysiological properties and most histological parameters of the SU nerve did not differ among MR, AR, and AR-Tactile groups. By contrast, at PND 14 and/or 21, the SU nerve of AR rats showed a lower CAP amplitude and area, and a significant reduction in myelin area and myelin thickness, which were accompanied by a reduction in axon area (day 21 only) compared to the nerves of MR rats. Tactile stimulation (AR-Tactile group) partially prevented most of these alterations. These results suggest that sensory cues from the mother and/or littermates during the first 7-14 PND are relevant for the proper development and function of the adult SU nerve. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 78: 351-362, 2018. © 2017 Wiley Periodicals, Inc.

Raman spectroscopic detection of peripheral nerves towards nerve-sparing surgery

Science.gov (United States)

Minamikawa, Takeo; Harada, Yoshinori; Takamatsu, Tetsuro

2017-02-01

The peripheral nervous system plays an important role in motility, sensory, and autonomic functions of the human body. Preservation of peripheral nerves in surgery, namely nerve-sparing surgery, is now promising technique to avoid functional deficits of the limbs and organs following surgery as an aspect of the improvement of quality of life of patients. Detection of peripheral nerves including myelinated and unmyelinated nerves is required for the nerve-sparing surgery; however, conventional nerve identification scheme is sometimes difficult to identify peripheral nerves due to similarity of shape and color to non-nerve tissues or its limited application to only motor peripheral nerves. To overcome these issues, we proposed a label-free detection technique of peripheral nerves by means of Raman spectroscopy. We found several fingerprints of peripheral myelinated and unmyelinated nerves by employing a modified principal component analysis of typical spectra including myelinated nerve, unmyelinated nerve, and adjacent tissues. We finally realized the sensitivity of 94.2% and the selectivity of 92.0% for peripheral nerves including myelinated and unmyelinated nerves against adjacent tissues. Although further development of an intraoperative Raman spectroscopy system is required for clinical use, our proposed approach will serve as a unique and powerful tool for peripheral nerve detection for nerve-sparing surgery in the future.

Selectivity and Longevity of Peripheral-Nerve and Machine Interfaces: A Review

Directory of Open Access Journals (Sweden)

Usman Ghafoor

2017-10-01

Full Text Available For those individuals with upper-extremity amputation, a daily normal living activity is no longer possible or it requires additional effort and time. With the aim of restoring their sensory and motor functions, theoretical and technological investigations have been carried out in the field of neuroprosthetic systems. For transmission of sensory feedback, several interfacing modalities including indirect (non-invasive, direct-to-peripheral-nerve (invasive, and cortical stimulation have been applied. Peripheral nerve interfaces demonstrate an edge over the cortical interfaces due to the sensitivity in attaining cortical brain signals. The peripheral nerve interfaces are highly dependent on interface designs and are required to be biocompatible with the nerves to achieve prolonged stability and longevity. Another criterion is the selection of nerves that allows minimal invasiveness and damages as well as high selectivity for a large number of nerve fascicles. In this paper, we review the nerve-machine interface modalities noted above with more focus on peripheral nerve interfaces, which are responsible for provision of sensory feedback. The invasive interfaces for recording and stimulation of electro-neurographic signals include intra-fascicular, regenerative-type interfaces that provide multiple contact channels to a group of axons inside the nerve and the extra-neural-cuff-type interfaces that enable interaction with many axons around the periphery of the nerve. Section Current Prosthetic Technology summarizes the advancements made to date in the field of neuroprosthetics toward the achievement of a bidirectional nerve-machine interface with more focus on sensory feedback. In the Discussion section, the authors propose a hybrid interface technique for achieving better selectivity and long-term stability using the available nerve interfacing techniques.

Selectivity and Longevity of Peripheral-Nerve and Machine Interfaces: A Review

Science.gov (United States)

Ghafoor, Usman; Kim, Sohee; Hong, Keum-Shik

2017-01-01

For those individuals with upper-extremity amputation, a daily normal living activity is no longer possible or it requires additional effort and time. With the aim of restoring their sensory and motor functions, theoretical and technological investigations have been carried out in the field of neuroprosthetic systems. For transmission of sensory feedback, several interfacing modalities including indirect (non-invasive), direct-to-peripheral-nerve (invasive), and cortical stimulation have been applied. Peripheral nerve interfaces demonstrate an edge over the cortical interfaces due to the sensitivity in attaining cortical brain signals. The peripheral nerve interfaces are highly dependent on interface designs and are required to be biocompatible with the nerves to achieve prolonged stability and longevity. Another criterion is the selection of nerves that allows minimal invasiveness and damages as well as high selectivity for a large number of nerve fascicles. In this paper, we review the nerve-machine interface modalities noted above with more focus on peripheral nerve interfaces, which are responsible for provision of sensory feedback. The invasive interfaces for recording and stimulation of electro-neurographic signals include intra-fascicular, regenerative-type interfaces that provide multiple contact channels to a group of axons inside the nerve and the extra-neural-cuff-type interfaces that enable interaction with many axons around the periphery of the nerve. Section Current Prosthetic Technology summarizes the advancements made to date in the field of neuroprosthetics toward the achievement of a bidirectional nerve-machine interface with more focus on sensory feedback. In the Discussion section, the authors propose a hybrid interface technique for achieving better selectivity and long-term stability using the available nerve interfacing techniques. PMID:29163122

Effect of low frequency transcutaneous magnetic stimulation on sensory and motor transmission.

Science.gov (United States)

Leung, Albert; Shukla, Shivshil; Lee, Jacquelyn; Metzger-Smith, Valerie; He, Yifan; Chen, Jeffrey; Golshan, Shahrokh

2015-09-01

Peripheral nerve injury diminishes fast conducting large myelinated afferent fibers transmission but enhances smaller pain transmitting fibers firing. This aberrant afferent neuronal behavior contributes to development of chronic post-traumatic peripheral neuropathic pain (PTP-NP). Non-invasive dynamic magnetic flux stimulation has been implicated in treating PTP-NP, a condition currently not adequately addressed by other therapies including transcutaneous electrical nerve stimulation (TENS). The current study assessed the effect of low frequency transcutaneous magnetic stimulation (LFTMS) on peripheral sensory thresholds, nerve conduction properties, and TENS induced fast afferent slowing effect as measured by motor and sensory conduction studies in the ulnar nerve. Results indicated sham LFTMS with TENS (Sham + TENS) significantly (P = 0.02 and 0.007, respectively) reduces sensory conduction velocity (CV) and increases sensory onset latency (OL), and motor peak latency (PL) whereas, real LFTMS with TENS (Real + TENS) reverses effects of TENS on sensory CV and OL, and significantly (P = 0.036) increases the sensory PL. LFTMS alone significantly (P sensory PL and onset-to-peak latency. LFTMS appears to reverse TENS slowing effect on fast conducting fibers and casts a selective peripheral modulatory effect on slow conducting pain afferent fibers. © 2015 Wiley Periodicals, Inc.

Peripheral nerve function during hyperglycemic clamping in insulin-dependent diabetic patients

DEFF Research Database (Denmark)

Sindrup, S H; Ejlertsen, B; Gjessing, H

1989-01-01

The influence of hyperglycemia on peripheral nerve function was studied in 9 patients with long-term insulin-dependent diabetes. Blood glucose concentration was raised 13.5 +/- 0.5 mmol/l (mean +/- SEM) within 15 min and kept approximately 15 mmol/l over basal level for 120 min by intravenous...... glucose infusion. Hyperglycemia was accompanied by increased plasma osmolality. Sensory and motor nerve conduction and distal motor latency in the ulnar nerve were determined before, immediately after induction of hyperglycemia, and again after 120 min hyperglycemia. Distal (5th finger - wrist......) and proximal (wrist - elbow) sensory nerve conduction showed an insignificant increase as hyperglycemia was induced. During hyperglycemia mean distal sensory conduction decreased from 53.1 m/s to 50.4 m/s (P less than 0.05) and mean proximal sensory conduction decreased from 56.0 m/s to 54.2 m/s (P less than 0...

Microsurgical reconstruction of large nerve defects using autologous nerve grafts.

Science.gov (United States)

Daoutis, N K; Gerostathopoulos, N E; Efstathopoulos, D G; Misitizis, D P; Bouchlis, G N; Anagnostou, S K

1994-01-01

Between 1986 and 1993, 643 patients with peripheral nerve trauma were treated in our clinic. Primary neurorraphy was performed in 431 of these patients and nerve grafting in 212 patients. We present the functional results after nerve grafting in 93 patients with large nerve defects who were followed for more than 2 years. Evaluation of function was based on the Medical Research Council (MRC) classification for motor and sensory recovery. Factors affecting functional outcome, such as age of the patient, denervation time, length of the defect, and level of the injury were noted. Good results according to the MRC classification were obtained in the majority of cases, although function remained less than that of the uninjured side.

Tenascin-C in peripheral nerve morphogenesis.

Science.gov (United States)

Chiquet, M; Wehrle-Haller, B

1994-01-01

The extracellular matrix (ECM) molecule tenascin/cytotactin (TN-C) is expressed at a high level by satellite (glial precursor) cells in developing peripheral nerves of the chick embryo; synthesis of its mRNA peaks at the time period when axonal growth is maximal. When offered as a substrate in vitro, TN-C mediates neurite outgrowth by both motor and sensory neurons. The ability to grow neurites on TN-C is developmentally regulated: sensory neurons from 4-day chick embryos (the stage at which peripheral nerves start to develop) grow immediately and rapidly, whereas neurons from older embryos respond with a long delay. A TN-C domain responsible for this activity is located within the C-terminal (distal) portion of TN-C subunits. Integrin receptors seem to be involved on peripheral neurites because their growth on TN-C is completely blocked by antibodies to beta 1 integrins. In striking contrast to neuronal processes, nerve satellite cells can attach to a TN-C substrate but are completely inhibited in their migratory activity. Artificial substrate borders between tenascin and fibronectin or laminin act as selective barriers that allow neurites to pass while holding up satellite cells. The repulsive action of TN-C on satellite cells is similar to that observed for other cell types and is likely to be mediated by additional TN-C domains. In view of these data, it is surprising that mice seem to develop normally without a functional TN-C gene. TN-C is likely to be redundant, that is, its dual action on cell adhesion is shared by other molecules.(ABSTRACT TRUNCATED AT 250 WORDS)

Biomarkers of neuropathic pain in skin nerve degeneration neuropathy: contact heat-evoked potentials as a physiological signature.

Science.gov (United States)

Wu, Shao-Wei; Wang, Yi-Chia; Hsieh, Paul-Chen; Tseng, Ming-Tsung; Chiang, Ming-Chang; Chu, Chih-Pang; Feng, Fang-Ping; Lin, Yea-Huey; Hsieh, Sung-Tsang; Chao, Chi-Chao

2017-03-01

Contact heat-evoked potentials (CHEPs) have become an established method of assessing small-fiber sensory nerves; however, their potential as a physiological signature of neuropathic pain symptoms has not been fully explored. To investigate the diagnostic efficacy in examining small-fiber sensory nerve degeneration, the relationship with skin innervations, and clinical correlates with sensory symptoms, we recruited 188 patients (115 men) with length-dependent sensory symptoms and reduced intraepidermal nerve fiber (IENF) density at the distal leg to perform CHEP, quantitative sensory testing, and nerve conduction study. Fifty-seven age- and sex-matched controls were enrolled for comparison of CHEP and skin innervation. Among patients with neuropathy, 144 patients had neuropathic pain and 64 cases had evoked pain. Compared with quantitative sensory testing and nerve conduction study parameters, CHEP amplitudes showed the highest sensitivity for diagnosing small-fiber sensory nerve degeneration and exhibited the strongest correlation with IENF density in multiple linear regression. Contact heat-evoked potential amplitudes were strongly correlated with the degree of skin innervation in both patients with neuropathy and controls, and the slope of the regression line between CHEP amplitude and IENF density was higher in patients with neuropathy than in controls. Patients with evoked pain had higher CHEP amplitude than those without evoked pain, independent of IENF density. Receiver operating characteristic analysis showed that CHEP had better performance in diagnosing small-fiber sensory nerve degeneration than thermal thresholds. Furthermore, CHEPs showed superior classification accuracy with respect to evoked pain. In conclusion, CHEP is a sensitive tool to evaluate pathophysiology of small-fiber sensory nerve and serves as a physiological signature of neuropathic pain symptoms.

Chondroitinase C Selectively Degrades Chondroitin Sulfate Glycosaminoglycans that Inhibit Axonal Growth within the Endoneurium of Peripheral Nerve.

Science.gov (United States)

Graham, James B; Muir, David

2016-01-01

The success of peripheral nerve regeneration is highly dependent on the regrowth of axons within the endoneurial basal lamina tubes that promote target-oriented pathfinding and appropriate reinnervation. Restoration of nerve continuity at this structural level after nerve transection injury by direct repair and nerve grafting remains a major surgical challenge. Recently, biological approaches that alter the balance of growth inhibitors and promoters in nerve have shown promise to improve appropriate axonal regeneration and recovery of peripheral nerve function. Chondroitin sulfate proteoglycans (CSPGs) are known inhibitors of axonal growth. This growth inhibition is mainly associated with a CSPG's glycosaminoglycan chains. Enzymatic degradation of these chains with chondroitinase eliminates this inhibitory activity and, when applied in vivo, can improve the outcome of nerve repair. To date, these encouraging findings were obtained with chondroitinase ABC (a pan-specific chondroitinase). The aim of this study was to examine the distribution of CSPG subtypes in rodent, rabbit, and human peripheral nerve and to test more selective biological enzymatic approaches to improve appropriate axonal growth within the endoneurium and minimize aberrant growth. Here we provide evidence that the endoneurium, but not the surrounding epineurium, is rich in CSPGs that have glycosaminoglycan chains readily degraded by chondroitinase C. Biochemical studies indicate that chondroitinase C has degradation specificity for 6-sulfated glycosaminoglycans found in peripheral nerve. We found that chondroitinase C degrades and inactivates inhibitory CSPGs within the endoneurium but not so much in the surrounding nerve compartments. Cryoculture bioassays (neurons grown on tissue sections) show that chondroitinase C selectively and significantly enhanced neuritic growth associated with the endoneurial basal laminae without changing growth-inhibiting properties of the surrounding epineurium

Ultrasound of the sural nerve: Normal anatomy on cadaveric dissection and case series

International Nuclear Information System (INIS)

Belsack, Dries; Jager, Tjeerd; Scafoglieri, Aldo; Vanderdood, Kurt; Van Hedent, Eddy; Vanhoenacker, Filip; Marcelis, Stefaan; De Maeseneer, Michel

2013-01-01

The sural nerve is a small sensory nerve innervating the lateral aspect of the ankle and foot. Clinical symptoms of pathology may present as atypical sensory changes in this region. We present the normal anatomy and ultrasound technique for examination of the sural nerve based on an anatomical dissection, as well as imaging in a normal volunteer. We also present a case series (n = 10) of different conditions of the sural nerve that we encountered based on a review of interesting cases from 4 institutions. The pathological conditions included neuropathy related to stripping or venous laser surgery, compression by abscess, Lyme disease, nerve tumors, traumatic transsection, and encasement by fibrous plaque and edema. Ultrasound with its exquisite resolution is the preferred imaging method for examining the sural nerve in patients with unexplained sensory changes at the lateral aspect of the ankle and foot

Ultrasound of the sural nerve: Normal anatomy on cadaveric dissection and case series

Energy Technology Data Exchange (ETDEWEB)

Belsack, Dries, E-mail: dries.belsack@uzbrussel.be [Department of Radiology, UZ Brussel, Laarbeeklaan 101, 1090 Jette, Brussels (Belgium); Jager, Tjeerd, E-mail: tjeerd.jager@asz.be [Department of Radiology, Aalsters Stedelijk Ziekenhuis, Merestraat 80, 9300 Aalst (Belgium); Scafoglieri, Aldo, E-mail: aldo.scafoglieri@vub.ac.be [Department of Experimental Anatomy, Free University Brussels, Laarbeeklaan 103, 1090 Jette (Belgium); Vanderdood, Kurt, E-mail: kvanderd@yahoo.com [Department of Radiology, Maaslandziekenhuis, Dr H van der Hoffplein 1, 6162 Sittard-Geleen, Sittard (Netherlands); Van Hedent, Eddy, E-mail: eddy.vanhedent@asz.be [Department of Radiology, Aalsters Stedelijk Ziekenhuis, Merestraat 80, 9300 Aalst (Belgium); Vanhoenacker, Filip, E-mail: filip.vanhoenacker@telenet.be [Department of Radiology, AZ Sint-Maarten, Duffel-Mechelen, Rooienberg 25, 2570 Duffel (Belgium); Marcelis, Stefaan, E-mail: stefaan.marcelis@sintandriesstielt.be [Department of Radiology, Sint Andriesziekenhuis, Krommewalstraat 11, 8700 Tielt (Belgium); De Maeseneer, Michel, E-mail: michel.demaeseneer@uzbrussel.be [Department of Radiology, UZ Brussel, Laarbeeklaan 101, 1090 Jette, Brussels (Belgium)

2013-11-01

The sural nerve is a small sensory nerve innervating the lateral aspect of the ankle and foot. Clinical symptoms of pathology may present as atypical sensory changes in this region. We present the normal anatomy and ultrasound technique for examination of the sural nerve based on an anatomical dissection, as well as imaging in a normal volunteer. We also present a case series (n = 10) of different conditions of the sural nerve that we encountered based on a review of interesting cases from 4 institutions. The pathological conditions included neuropathy related to stripping or venous laser surgery, compression by abscess, Lyme disease, nerve tumors, traumatic transsection, and encasement by fibrous plaque and edema. Ultrasound with its exquisite resolution is the preferred imaging method for examining the sural nerve in patients with unexplained sensory changes at the lateral aspect of the ankle and foot.

The morphological substrate for Renal Denervation : Nerve distribution patterns and parasympathetic nerves. A post-mortem histological study

NARCIS (Netherlands)

van Amsterdam, Wouter A C; Blankestijn, Peter J; Goldschmeding, Roel; Bleys, Ronald L A W

2015-01-01

BACKGROUND: Renal Denervation as a possible treatment for hypertension has been studied extensively, but knowledge on the distribution of nerves surrounding the renal artery is still incomplete. While sympathetic and sensory nerves have been demonstrated, there is no mention of the presence of

Characterization and diagnostic evaluation of chronic polyneuropathies induced by oxaliplatin and docetaxel comparing skin biopsy to quantitative sensory testing and nerve conduction studies

DEFF Research Database (Denmark)

Krøigård, T; Schrøder, H D; Qvortrup, C

2014-01-01

was to characterize the neuropathies with regard to symptoms, neurological signs and objective evidence of damage to the structure and function of the peripheral nerves. Furthermore, the diagnostic values of skin biopsy, quantitative sensory testing (QST) and nerve conduction studies (NCS) were compared. METHODS......: Patients complaining of neuropathy symptoms at least 3 months after completion of treatment with oxaliplatin (n = 20) or docetaxel (n = 20) were recruited from the Department of Oncology or using hospital records. Neuropathy scores were determined along with the intraepidermal nerve fibre density in skin....... Mechanical detection threshold was most often affected in the QST. NCS, QTS and skin biopsy were abnormal in 11, 13 and 17 and 7, 11 and 15 of the oxaliplatin-treated patients and docetaxel-treated patients, respectively. CONCLUSIONS: Chemotherapy-induced peripheral neuropathy after oxaliplatin or docetaxel...

Trigeminal neuralgia and facial nerve paralysis

Energy Technology Data Exchange (ETDEWEB)

Borges, Alexandra [IPOFG, Department of Radiology, Lisbon (Portugal)

2005-03-01

The trigeminal nerve is the largest of the cranial nerves. It provides sensory input from the face and motor innervation to the muscles of mastication. The facial nerve is the cranial nerve with the longest extracranial course, and its main functions include motor innervation to the muscles of facial expression, sensory control of lacrimation and salivation, control of the stapedial reflex and to carry taste sensation from the anterior two-thirds of the tongue. In order to be able adequately to image and follow the course of these cranial nerves and their main branches, a detailed knowledge of neuroanatomy is required. As we are dealing with very small anatomic structures, high resolution dedicated imaging studies are required to pick up normal and pathologic nerves. Whereas CT is best suited to demonstrate bony neurovascular foramina and canals, MRI is preferred to directly visualize the nerve. It is also the single technique able to detect pathologic processes afflicting the nerve without causing considerable expansion such as is usually the case in certain inflammatory/infectious conditions, perineural spread of malignancies and in very small intrinsic tumours. Because a long course from the brainstem nuclei to the peripheral branches is seen, it is useful to subdivide the nerve in several segments and then tailor the imaging modality and the imaging study to that specific segment. This is particularly true in cases where topographic diagnosis can be used to locate a lesion in the course of these nerves. (orig.)

Trigeminal neuralgia and facial nerve paralysis

International Nuclear Information System (INIS)

Borges, Alexandra

2005-01-01

The trigeminal nerve is the largest of the cranial nerves. It provides sensory input from the face and motor innervation to the muscles of mastication. The facial nerve is the cranial nerve with the longest extracranial course, and its main functions include motor innervation to the muscles of facial expression, sensory control of lacrimation and salivation, control of the stapedial reflex and to carry taste sensation from the anterior two-thirds of the tongue. In order to be able adequately to image and follow the course of these cranial nerves and their main branches, a detailed knowledge of neuroanatomy is required. As we are dealing with very small anatomic structures, high resolution dedicated imaging studies are required to pick up normal and pathologic nerves. Whereas CT is best suited to demonstrate bony neurovascular foramina and canals, MRI is preferred to directly visualize the nerve. It is also the single technique able to detect pathologic processes afflicting the nerve without causing considerable expansion such as is usually the case in certain inflammatory/infectious conditions, perineural spread of malignancies and in very small intrinsic tumours. Because a long course from the brainstem nuclei to the peripheral branches is seen, it is useful to subdivide the nerve in several segments and then tailor the imaging modality and the imaging study to that specific segment. This is particularly true in cases where topographic diagnosis can be used to locate a lesion in the course of these nerves. (orig.)

Neurophysiological approach to disorders of peripheral nerve

DEFF Research Database (Denmark)

Crone, Clarissa; Krarup, Christian

2013-01-01

Disorders of the peripheral nerve system (PNS) are heterogeneous and may involve motor fibers, sensory fibers, small myelinated and unmyelinated fibers and autonomic nerve fibers, with variable anatomical distribution (single nerves, several different nerves, symmetrical affection of all nerves......, plexus, or root lesions). Furthermore pathological processes may result in either demyelination, axonal degeneration or both. In order to reach an exact diagnosis of any neuropathy electrophysiological studies are crucial to obtain information about these variables. Conventional electrophysiological...

a technique to repair peripheral nerve injury

African Journals Online (AJOL)

attached nerve does occi.rr, and functional recovery (sensory and motor) has been demonstrated. ..... Brachial plexus. Upper trunk to lower. 19 Nov 1998 ... Fractured. 13 Mar 1998 Mid shaft hiunerus Radial nerve to. 14 Mar 1999 humerus cut.

Serotonin induces memory-like, rapamycin-sensitive hyperexcitability in sensory axons of aplysia that contributes to injury responses.

Science.gov (United States)

Weragoda, Ramal M S; Walters, Edgar T

2007-09-01

The induction of long-term facilitation (LTF) of synapses of Aplysia sensory neurons (SNs) by serotonin (5-HT) has provided an important mechanistic model of memory, but little is known about other long-term effects of 5-HT on sensory properties. Here we show that crushing peripheral nerves results in long-term hyperexcitability (LTH) of the axons of these nociceptive SNs that requires 5-HT activity in the injured nerve. Serotonin application to a nerve segment induces local axonal (but not somal) LTH that is inhibited by 5-HT-receptor antagonists. Blockade of crush-induced axonal LTH by an antagonist, methiothepin, provides evidence for mediation of this injury response by 5-HT. This is the first demonstration in any axon of neuromodulator-induced LTH, a phenomenon potentially important for long-lasting pain. Methiothepin does not reduce axonal LTH induced by local depolarization, so 5-HT is not required for all forms of axonal LTH. Serotonin-induced axonal LTH is expressed as reduced spike threshold and increased repetitive firing, whereas depolarization-induced LTH involves only reduced threshold. Like crush- and depolarization-induced LTH, 5-HT-induced LTH is blocked by inhibiting protein synthesis. Blockade by rapamycin, which also blocks synaptic LTF, is interesting because the eukaryotic protein kinase that is the target of rapamycin (TOR) has a conserved role in promoting growth by stimulating translation of proteins required for translation. Rapamycin sensitivity suggests that localized increases in translation of proteins that promote axonal conduction and excitability at sites of nerve injury may be regulated by the same signals that increase translation of proteins that promote neuronal growth.

Using Arrays of Microelectrodes Implanted in Residual Peripheral Nerves to Provide Dextrous Control of, and Modulated Sensory Feedback from, a Hand Prosthesis

Science.gov (United States)

2015-10-01

extended that work by investigating multiple aspects important for developing future bidirectional neural prostheses based on high-count microelectrode...Fan J M, Kao J C, Stavisky S D, Ryu S and Shenoy K 2012 A recurrent neural network for closed-loop intracortical brain-machine interface decoders J...Peripheral Nerve Interface, Prosthetic Hand, Neural Prosthesis, Sensory Feedback, Micro-stimulation, Electrophysiology, Action Potentials, Micro

Recovery of function, peripheral sensitization and sensory neurone activation by novel pathways following axonal injury in Aplysia californica.

Science.gov (United States)

Dulin, M F; Steffensen, I; Morris, C E; Walters, E T

1995-10-01

Recovery of behavioural and sensory function was examined following unilateral pedal nerve crush in Aplysia californica. Nerve crush that transected all axons connecting the tail to the central nervous system (CNS) eliminated the ipsilateral tail-evoked siphon reflex, whose sensory input travels in the crushed tail nerve (p9). The first reliable signs of recovery of this reflex were observed within 1 week, and most animals displayed tail-evoked siphon responses within 2 weeks. Wide-dynamic-range mechanosensory neurons with somata in the ventrocaudal (VC) cluster of the ipsilateral pleural ganglion exhibited a few receptive fields (RFs) on the tail 3 weeks after unilateral pedal nerve crush, indicating that the RFs had either regenerated or been reconnected to the central somata. These RFs were smaller and sensitized compared with corresponding RFs on the contralateral, uncrushed side. Centrally conducted axon responses of VC sensory neurones to electrical stimulation distal to the nerve crush site did not reappear until at least 10 days after the crush. Because the crush site was much closer to the CNS than to the tail, the failure of axon responses to be restored earlier than the behavioural responses indicates that early stages of reflex recovery are not due to regeneration of VC sensory neurone axons into the tail. Following nerve crush, VC sensory neurones often could be activated by stimulating central connectives or peripheral nerves that do not normally contain the sensory neurone's axons. These results suggest that recovery of behavioral function after nerve injury involves complex mechanisms, including regenerative growth of axotomized VC sensory neurones, sensitization of regenerating RFs and sprouting of VC sensory neurone fibres within the CNS. Furthermore, the rapidity of behavioural recovery indicates that its initial phases are mediated by additional mechanisms, perhaps centripetal regeneration of unidentified sensory neurones having peripheral

High-level inhibition of mitochondrial complexes III and IV is required to increase glutamate release from the nerve terminal

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Kilbride Seán M

2011-07-01

Full Text Available Abstract Background The activities of mitochondrial complex III (ubiquinol-cytochrome c reductase, EC 1.10.2.2 and complex IV (cytochrome c oxidase EC 1.9.3.1 are reduced by 30-70% in Huntington's disease and Alzheimer's disease, respectively, and are associated with excitotoxic cell death in these disorders. In this study, we investigated the control that complexes III and complex IV exert on glutamate release from the isolated nerve terminal. Results Inhibition of complex III activity by 60-90% was necessary for a major increase in the rate of Ca2+-independent glutamate release to occur from isolated nerve terminals (synaptosomes depolarized with 4-aminopyridine or KCl. Similarly, an 85-90% inhibition of complex IV activity was required before a major increase in the rate of Ca2+-independent glutamate release from depolarized synaptosomes was observed. Inhibition of complex III and IV activities by ~ 60% and above was required before rates of glutamate efflux from polarized synaptosomes were increased. Conclusions These results suggest that nerve terminal mitochondria possess high reserves of complex III and IV activity and that high inhibition thresholds must be reached before excess glutamate is released from the nerve terminal. The implications of the results in the context of the relationship between electron transport chain enzyme deficiencies and excitotoxicity in neurodegenerative disorders are discussed.

High-level inhibition of mitochondrial complexes III and IV is required to increase glutamate release from the nerve terminal

LENUS (Irish Health Repository)

Kilbride, Sean M

2011-07-26

Abstract Background The activities of mitochondrial complex III (ubiquinol-cytochrome c reductase, EC 1.10.2.2) and complex IV (cytochrome c oxidase EC 1.9.3.1) are reduced by 30-70% in Huntington\\'s disease and Alzheimer\\'s disease, respectively, and are associated with excitotoxic cell death in these disorders. In this study, we investigated the control that complexes III and complex IV exert on glutamate release from the isolated nerve terminal. Results Inhibition of complex III activity by 60-90% was necessary for a major increase in the rate of Ca2+-independent glutamate release to occur from isolated nerve terminals (synaptosomes) depolarized with 4-aminopyridine or KCl. Similarly, an 85-90% inhibition of complex IV activity was required before a major increase in the rate of Ca2+-independent glutamate release from depolarized synaptosomes was observed. Inhibition of complex III and IV activities by ~ 60% and above was required before rates of glutamate efflux from polarized synaptosomes were increased. Conclusions These results suggest that nerve terminal mitochondria possess high reserves of complex III and IV activity and that high inhibition thresholds must be reached before excess glutamate is released from the nerve terminal. The implications of the results in the context of the relationship between electron transport chain enzyme deficiencies and excitotoxicity in neurodegenerative disorders are discussed.

Deficiency in monocarboxylate transporter 1 (MCT1) in mice delays regeneration of peripheral nerves following sciatic nerve crush

KAUST Repository

Morrison, Brett M.; Tsingalia, Akivaga; Vidensky, Svetlana; Lee, Youngjin; Jin, Lin; Farah, Mohamed H.; Lengacher, Sylvain; Magistretti, Pierre J.; Pellerin, Luc; Rothsteinb, Jeffrey D.

2015-01-01

Peripheral nerve regeneration following injury occurs spontaneously, but many of the processes require metabolic energy. The mechanism of energy supply to axons has not previously been determined. In the central nervous system, monocarboxylate transporter 1 (MCT1), expressed in oligodendroglia, is critical for supplying lactate or other energy metabolites to axons. In the current study, MCT1 is shown to localize within the peripheral nervous system to perineurial cells, dorsal root ganglion neurons, and Schwann cells by MCT1 immunofluorescence in wild-type mice and tdTomato fluorescence in MCT1 BAC reporter mice. To investigate whether MCT1 is necessary for peripheral nerve regeneration, sciatic nerves of MCT1 heterozygous mice are crushed and peripheral nerve regeneration was quantified electrophysiologically and anatomically. Compound muscle action potential (CMAP) recovery is delayed from a median of 21. days in wild-type mice to greater than 38. days in MCT1 heterozygote mice. In fact, half of the MCT1 heterozygote mice have no recovery of CMAP at 42. days, while all of the wild-type mice recovered. In addition, muscle fibers remain 40% more atrophic and neuromuscular junctions 40% more denervated at 42. days post-crush in the MCT1 heterozygote mice than wild-type mice. The delay in nerve regeneration is not only in motor axons, as the number of regenerated axons in the sural sensory nerve of MCT1 heterozygote mice at 4. weeks and tibial mixed sensory and motor nerve at 3. weeks is also significantly reduced compared to wild-type mice. This delay in regeneration may be partly due to failed Schwann cell function, as there is reduced early phagocytosis of myelin debris and remyelination of axon segments. These data for the first time demonstrate that MCT1 is critical for regeneration of both sensory and motor axons in mice following sciatic nerve crush.

Inhibition of KLF7-Targeting MicroRNA 146b Promotes Sciatic Nerve Regeneration.

Science.gov (United States)

Li, Wen-Yuan; Zhang, Wei-Ting; Cheng, Yong-Xia; Liu, Yan-Cui; Zhai, Feng-Guo; Sun, Ping; Li, Hui-Ting; Deng, Ling-Xiao; Zhu, Xiao-Feng; Wang, Ying

2018-06-01

A previous study has indicated that Krüppel-like factor 7 (KLF7), a transcription factor that stimulates Schwann cell (SC) proliferation and axonal regeneration after peripheral nerve injury, is a promising therapeutic transcription factor in nerve injury. We aimed to identify whether inhibition of microRNA-146b (miR-146b) affected SC proliferation, migration, and myelinated axon regeneration following sciatic nerve injury by regulating its direct target KLF7. SCs were transfected with miRNA lentivirus, miRNA inhibitor lentivirus, or KLF7 siRNA lentivirus in vitro. The expression of miR146b and KLF7, as well as SC proliferation and migration, were subsequently evaluated. In vivo, an acellular nerve allograft (ANA) followed by injection of GFP control vector or a lentiviral vector encoding an miR-146b inhibitor was used to assess the repair potential in a model of sciatic nerve gap. miR-146b directly targeted KLF7 by binding to the 3'-UTR, suppressing KLF7. Up-regulation of miR-146b and KLF7 knockdown significantly reduced the proliferation and migration of SCs, whereas silencing miR-146b resulted in increased proliferation and migration. KLF7 protein was localized in SCs in which miR-146b was expressed in vivo. Similarly, 4 weeks after the ANA, anti-miR-146b increased KLF7 and its target gene nerve growth factor cascade, promoting axonal outgrowth. Closer analysis revealed improved nerve conduction and sciatic function index score, and enhanced expression of neurofilaments, P0 (anti-peripheral myelin), and myelinated axon regeneration. Our findings provide new insight into the regulation of KLF7 by miR-146b during peripheral nerve regeneration and suggest a potential therapeutic strategy for peripheral nerve injury.

Insulin and IGF-II, but not IGF-I, stimulate the in vitro regeneration of adult frog sciatic sensory axons

DEFF Research Database (Denmark)

Edbladh, M; Svenningsen, Åsa Fex; Ekström, P A

1994-01-01

We used the in vitro regenerating frog sciatic nerve to look for effects of insulin and insulin-like growth factors I and II (IGF-I, IGF-II) on regeneration of sensory axons and on injury induced support cell proliferation in the outgrowth region. In nerves cultured for 11 days, a physiological...... dose (10 ng/ml, approximately 2 nM) of insulin or IGF-II increased ganglionic protein synthesis (by 20% and 50%, respectively) as well as the level of newly formed, radiolabelled axonal material distal to a crush injury (both by 80%), compared to untreated, paired controls. In addition, insulin...... increased the outgrowth distance of the furthest regenerating sensory axons by 10%. The preparation was particularly sensitive to insulin during the first 5 days of culturing. Furthermore, both insulin and IGF-II were found to inhibit proliferation of support cells in the outgrowth region in a manner...

Inhibition of Parkinsonian tremor with cutaneous afferent evoked by transcutaneous electrical nerve stimulation.

Science.gov (United States)

Hao, Man-Zhao; Xu, Shao-Qin; Hu, Zi-Xiang; Xu, Fu-Liang; Niu, Chuan-Xin M; Xiao, Qin; Lan, Ning

2017-07-14

Recent study suggests that tremor signals are transmitted by way of multi-synaptic corticospinal pathway. Neurophysiological studies have also demonstrated that cutaneous afferents exert potent inhibition to descending motor commands by way of spinal interneurons. We hypothesize in this study that cutaneous afferents could also affect the transmission of tremor signals, thus, inhibit tremor in patients with PD. We tested this hypothesis by activating cutaneous afferents in the dorsal hand skin innervated by superficial radial nerve using transcutaneous electrical nerve stimulation (TENS). Eight patients with PD having tremor dominant symptom were recruited to participate in this study using a consistent experimental protocol for tremor inhibition. Resting tremor and electromyogram (EMG) of muscles in the upper extremity of these subjects with PD were recorded, while surface stimulation was applied to the dorsal skin of the hand. Fifteen seconds of data were recorded for 5 s prior to, during and post stimulation. Power spectrum densities (PSDs) of tremor and EMG signals were computed for each data segment. The peak values of PSDs in three data segments were compared to detect evidence of tremor inhibition. At stimulation intensity from 1.5 to 1.75 times of radiating sensation threshold, apparent suppressions of tremor at wrist, forearm and upper arm and in the EMGs were observed immediately at the onset of stimulation. After termination of stimulation, tremor and rhythmic EMG bursts reemerged gradually. Statistical analysis of peak spectral amplitudes showed a significant difference in joint tremors and EMGs during and prior to stimulation in all 8 subjects with PD. The average percentage of suppression was 61.56% in tremor across all joints of all subjects, and 47.97% in EMG of all muscles. The suppression appeared to occur mainly in distal joints and muscles. There was a slight, but inconsistent effect on tremor frequency in the 8 patients with PD tested. Our

Evaluation of functional nerve recovery after reconstruction with a poly (DL-lactide-epsilon-caprolactone) nerve guide, filled with modified denatured muscle tissue

NARCIS (Netherlands)

Meek, MF; Den Dunnen, WFA; Schakenraad, JM; Robinson, PH

1996-01-01

The aim of this study was to compare the speed of functional nerve recovery after reconstruction with a biodegradable p(DLLA-epsilon -CL) nerve guide, as filled with either modified denatured muscle tissue (MDMT) or phosphate-buffered saline (PBS). To evaluate both motor and sensory nerve recovery,

Chondroitinase C Selectively Degrades Chondroitin Sulfate Glycosaminoglycans that Inhibit Axonal Growth within the Endoneurium of Peripheral Nerve.

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James B Graham

Full Text Available The success of peripheral nerve regeneration is highly dependent on the regrowth of axons within the endoneurial basal lamina tubes that promote target-oriented pathfinding and appropriate reinnervation. Restoration of nerve continuity at this structural level after nerve transection injury by direct repair and nerve grafting remains a major surgical challenge. Recently, biological approaches that alter the balance of growth inhibitors and promoters in nerve have shown promise to improve appropriate axonal regeneration and recovery of peripheral nerve function. Chondroitin sulfate proteoglycans (CSPGs are known inhibitors of axonal growth. This growth inhibition is mainly associated with a CSPG's glycosaminoglycan chains. Enzymatic degradation of these chains with chondroitinase eliminates this inhibitory activity and, when applied in vivo, can improve the outcome of nerve repair. To date, these encouraging findings were obtained with chondroitinase ABC (a pan-specific chondroitinase. The aim of this study was to examine the distribution of CSPG subtypes in rodent, rabbit, and human peripheral nerve and to test more selective biological enzymatic approaches to improve appropriate axonal growth within the endoneurium and minimize aberrant growth. Here we provide evidence that the endoneurium, but not the surrounding epineurium, is rich in CSPGs that have glycosaminoglycan chains readily degraded by chondroitinase C. Biochemical studies indicate that chondroitinase C has degradation specificity for 6-sulfated glycosaminoglycans found in peripheral nerve. We found that chondroitinase C degrades and inactivates inhibitory CSPGs within the endoneurium but not so much in the surrounding nerve compartments. Cryoculture bioassays (neurons grown on tissue sections show that chondroitinase C selectively and significantly enhanced neuritic growth associated with the endoneurial basal laminae without changing growth-inhibiting properties of the surrounding

Lingual nerve injury following surgical removal of mandibular third molar

Directory of Open Access Journals (Sweden)

Abduljaleel Azad Samad

2017-12-01

Full Text Available Background and objective: The close proximity of lingual nerve in relation to the lingual cortical bone of the posterior mandibular third molar is clinically important because lingual nerve may be subjected to trauma during surgical removal of the impacted lower third molar. This prospective study aimed to evaluate the incidence of lingual nerve paresthesia following surgical removal of mandibular third molar in College of Dentistry, Hawler Medical University. Methods: A total of 116 third molars surgery were carried out under local anesthesia for 116 patients for removal of lower mandibular teeth Using Terence Ward's incision made in all cases, and after that, the buccal flap was reflected, lingual tissues had been retracted during bone removal with a periosteal elevator. The sensory disturbance was evaluated on the 7th postoperative day by standard questioning the patients: “Do you have any unusual feeling in your tongue, lingual gingiva and mucosa of the floor of the mouth?" Results: One patient experienced sensory disturbance, the lingual nerve paresthesia incidence was 0.9% as a transient sensory disturbance, while no patient of permanent sensory disturbance. Conclusion: The incidence of injury to the lingual nerve can be minimized by careful clinical evaluation, surgeon’s experience, surgical approach and knowledge about anatomical landmarks during surgical removal of an impacted lower third molar tooth.

Sensory neuropathy in two Border collie puppies.

Science.gov (United States)

Vermeersch, K; Van Ham, L; Braund, K G; Bhatti, S; Tshamala, M; Chiers, K; Schrauwen, E

2005-06-01

A peripheral sensory neuropathy was diagnosed in two Border collie puppies. Neurological, electrophysiological and histopathological examinations suggested a purely sensory neuropathy with mainly distal involvement. Urinary incontinence was observed in one of the puppies and histological examination of the vagus nerve revealed degenerative changes. An inherited disorder was suspected.

Morphological study of the sensory innervation of the rat labial mucosa.

Science.gov (United States)

Yamamoto, T; Tazaki, M; Sakada, S

1986-02-01

The sensory innervation of the rat labial mucosa was investigated by means of methylene blue vital staining and osmic acid staining. Sensory receptors in this region were of three kinds (free nerve endings, encapsulated corpuscles and bush-like nerve endings) which constituted separate sensory units respectively. The encapsulated corpuscles were observed in the deep part of lamina propria, and distributed mainly in the margin of labial mucosa. Almost all (78.8%) of encapsulated corpuscles were of a simple type which had a non-branched axon terminal. No clew-like type corpuscles or glomerular-Meissner corpuscles were observed. The bush-like nerve endings were located in the lamina propria close to the epithelium, and localized in the central part of labial mucosa where the formation of papillae was remarkable. The density of the encapsulated corpuscles in the entire mucosa was 3.5-5.3/mm2, and that of the bush-like nerve endings in the densely distributed area was 38.9-60.6/mm2.

Artificial sensory organs: latest progress.

Science.gov (United States)

Nakamura, Tatsuo; Inada, Yuji; Shigeno, Keiji

2018-03-01

This study introduces the latest progress on the study of artificial sensory organs, with a special emphasis on the clinical results of artificial nerves and the concept of in situ tissue engineering. Peripheral nerves have a strong potential for regeneration. An artificial nerve uses this potential to recover a damaged peripheral nerve. The polyglycolic acid collagen tube (PGA-C tube) is a bio-absorbable tube stuffed with collagen of multi-chamber structure that consists of thin collagen films. The clinical application of the PGA-C tube began in 2002 in Japan. The number of PGA-C tubes used is now beyond 300, and satisfactory results have been reported on peripheral nerve repairs. This PGA-C tube is also effective for patients suffering from neuropathic pain.

Feedforward somatosensory inhibition is normal in cervical dystonia.

Science.gov (United States)

Ferrè, Elisa R; Ganos, Christos; Bhatia, Kailash P; Haggard, Patrick

2015-03-01

Insufficient cortical inhibition is a key pathophysiological finding in dystonia. Subliminal sensory stimuli were reported to transiently inhibit somatosensory processing. Here we investigated whether such subliminal feedforward inhibition is reduced in patients with cervical dystonia. Sixteen cervical dystonia patients and 16 matched healthy controls performed a somatosensory detection task. We measured the drop in sensitivity to detect a threshold-level digital nerve shock when it was preceded by a subliminal conditioning shock, compared to when it was not. Subliminal conditioning shocks reduced sensitivity to threshold stimuli to a similar extent in both patients and controls, suggesting that somatosensory subliminal feedforward inhibition is normal in cervical dystonia. Somatosensory feedforward inhibition was normal in this group of cervical dystonia patients. Our results qualify previous concepts of a general dystonic deficit in sensorimotor inhibitory processing. Copyright © 2015 Elsevier Ltd. All rights reserved.

Motor and sensory responses after percutaneous tibial nerve stimulation in multiple sclerosis patients with lower urinary tract symptoms treated in daily practice.

Science.gov (United States)

Zecca, C; Digesu, G A; Robshaw, P; Puccini, F; Khullar, V; Tubaro, A; Gobbi, C

2014-03-01

Posterior tibial nerve stimulation (PTNS) is an effective treatment option for lower urinary tract symptoms (LUTS) in multiple sclerosis (MS) patients. Patients with MS and LUTS unresponsive to medical treatment received PTNS for 12 weeks after saline urodynamics to evaluate the prevalence of motor, sensory and combined responses during PTNS and to determine whether the type of response can predict treatment outcome. LUTS were also assessed using a 3-day bladder diary, patient perception of bladder condition (PPBC) questionnaire, patient perception of intensity of urgency scale (PPIUS), Kings Health QOL questionnaire (KHQ) and Overactive Bladder Questionnaire (OAB-q) before and after treatment. Patients were considered as "responders" if they reported an improvement >50% in their LUTS according to the PPBC. Sensory, motor and combined sensory/motor responses were compared between responders and non-responders. Eighty-three patients were included. 61% (51/83) of patients were responders. Sensory, motor and combined sensory/motor responses were found in 64% (53/83), 6% (5/83) and 30% (25/83) of patients respectively. A sensory response alone, or in combination with a motor response, was better associated with a successful outcome than the presence of a motor response alone (P = 0.001). A sensory response, either alone or in combination with a motor response, is more frequent and seems to be better associated with a successful outcome of PTNS than motor response alone. © 2014 The Author(s) European Journal of Neurology © 2014 EFNS.

Ultrasound imaging accurately identifies the intercostobrachial nerve

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Ahmed K. Thallaj

2015-10-01

Full Text Available Objectives: To test the hypothesis that identification and blockade of the intercostobrachial nerve (ICBN can be achieved under ultrasound (US guidance using a small volume of local anesthetic. Methods: Twenty-eight adult male volunteers were examined at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia from November 2012 to September 2013. Intercostobrachial nerve blockade was performed using one ml of 2% lidocaine under US guidance. A sensory map of the blocked area was developed relative to the medial aspect of the humeral head. Results: The ICBN appears as a hyper-echoic structure. The nerve diameter was 2.3±0.28 mm, and the depth was 9±0.28 mm. The measurements of the sensory-blocked area relative to the medial aspect of the humeral head were as follows: 6.3±1.6 cm anteriorly; 6.2±2.9 cm posteriorly; 9.4±2.9 cm proximally; and 9.2±4.4 cm distally. Intercostobrachial nerve blockade using one ml of local anesthetic was successful in all cases. Conclusion: The present study described the sonographic anatomical details of the ICBN and its sensory distribution to successfully perform selective US-guided ICBN blockade.

Cell-type specific short-term plasticity at auditory nerve synapses controls feed-forward inhibition in the dorsal cochlear nucleus.

Science.gov (United States)

Sedlacek, Miloslav; Brenowitz, Stephan D

2014-01-01

Feed-forward inhibition (FFI) represents a powerful mechanism by which control of the timing and fidelity of action potentials in local synaptic circuits of various brain regions is achieved. In the cochlear nucleus, the auditory nerve provides excitation to both principal neurons and inhibitory interneurons. Here, we investigated the synaptic circuit associated with fusiform cells (FCs), principal neurons of the dorsal cochlear nucleus (DCN) that receive excitation from auditory nerve fibers and inhibition from tuberculoventral cells (TVCs) on their basal dendrites in the deep layer of DCN. Despite the importance of these inputs in regulating fusiform cell firing behavior, the mechanisms determining the balance of excitation and FFI in this circuit are not well understood. Therefore, we examined the timing and plasticity of auditory nerve driven FFI onto FCs. We find that in some FCs, excitatory and inhibitory components of FFI had the same stimulation thresholds indicating they could be triggered by activation of the same fibers. In other FCs, excitation and inhibition exhibit different stimulus thresholds, suggesting FCs and TVCs might be activated by different sets of fibers. In addition, we find that during repetitive activation, synapses formed by the auditory nerve onto TVCs and FCs exhibit distinct modes of short-term plasticity. Feed-forward inhibitory post-synaptic currents (IPSCs) in FCs exhibit short-term depression because of prominent synaptic depression at the auditory nerve-TVC synapse. Depression of this feedforward inhibitory input causes a shift in the balance of fusiform cell synaptic input towards greater excitation and suggests that fusiform cell spike output will be enhanced by physiological patterns of auditory nerve activity.

Sensory Coding by Cerebellar Mossy Fibres through Inhibition-Driven Phase Resetting and Synchronisation

Science.gov (United States)

Holtzman, Tahl; Jörntell, Henrik

2011-01-01

Temporal coding of spike-times using oscillatory mechanisms allied to spike-time dependent plasticity could represent a powerful mechanism for neuronal communication. However, it is unclear how temporal coding is constructed at the single neuronal level. Here we investigate a novel class of highly regular, metronome-like neurones in the rat brainstem which form a major source of cerebellar afferents. Stimulation of sensory inputs evoked brief periods of inhibition that interrupted the regular firing of these cells leading to phase-shifted spike-time advancements and delays. Alongside phase-shifting, metronome cells also behaved as band-pass filters during rhythmic sensory stimulation, with maximal spike-stimulus synchronisation at frequencies close to the idiosyncratic firing frequency of each neurone. Phase-shifting and band-pass filtering serve to temporally align ensembles of metronome cells, leading to sustained volleys of near-coincident spike-times, thereby transmitting synchronised sensory information to downstream targets in the cerebellar cortex. PMID:22046297

Sensory coding by cerebellar mossy fibres through inhibition-driven phase resetting and synchronisation.

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Tahl Holtzman

Full Text Available Temporal coding of spike-times using oscillatory mechanisms allied to spike-time dependent plasticity could represent a powerful mechanism for neuronal communication. However, it is unclear how temporal coding is constructed at the single neuronal level. Here we investigate a novel class of highly regular, metronome-like neurones in the rat brainstem which form a major source of cerebellar afferents. Stimulation of sensory inputs evoked brief periods of inhibition that interrupted the regular firing of these cells leading to phase-shifted spike-time advancements and delays. Alongside phase-shifting, metronome cells also behaved as band-pass filters during rhythmic sensory stimulation, with maximal spike-stimulus synchronisation at frequencies close to the idiosyncratic firing frequency of each neurone. Phase-shifting and band-pass filtering serve to temporally align ensembles of metronome cells, leading to sustained volleys of near-coincident spike-times, thereby transmitting synchronised sensory information to downstream targets in the cerebellar cortex.

Omental pedicle transposition and suture repair of peripheral nerve ...

African Journals Online (AJOL)

Abu wael

This study aimed to compare the effectiveness of omental pedicle transposition and ... Assessment of the nerve regeneration was based on functional (motor and sensory), ..... peripheral nerve fibers regenerating after crush, multiple crush, and.

Sensory nerve desensitization by resiniferatoxin improves glucose tolerance and increases insulin secretion in Zucker Diabetic Fatty rats and is associated with reduced plasma activity of dipeptidyl peptidase IV

DEFF Research Database (Denmark)

Gram, Dorte X; Hansen, Anker J; Deacon, Carolyn F

2005-01-01

Sensory nerve desensitization by capsaicin has been shown to improve the diabetic condition in Zucker Diabetic Fatty rats. However, administration of capsaicin to adult rats is associated with an increased mortality. Therefore, in this experiment, we examined the influence of resiniferatoxin...

Oral 2-hydroxyoleic acid inhibits reflex hypersensitivity and open-field-induced anxiety after spared nerve injury.

Science.gov (United States)

Avila-Martin, G; Galan-Arriero, I; Ferrer-Donato, A; Busquets, X; Gomez-Soriano, J; Escribá, P V; Taylor, J

2015-01-01

Recently, fatty acids have been shown to modulate sensory function in animal models of neuropathic pain. In this study, the antinociceptive effect of 2-hydroxyoleic acid (2-OHOA) was assessed following spared nerve injury (SNI) with reflex and cerebrally mediated behavioural responses. Initial antinociceptive behavioural screening of daily administration of 2-OHOA (400 mg/kg, p.o.) was assessed in Wistar rats by measuring hindlimb reflex hypersensitivity to von Frey and thermal plate stimulation up to 7 days after SNI, while its modulatory effect on lumbar spinal dorsal horn microglia reactivity was assessed with OX-42 immunohistochemistry. In vitro the effect of 2-OHOA (120 μM) on cyclooxygenase protein expression (COX-2/COX-1 ratio) in lipopolysaccharide-activated macrophage cells was tested with Western blot analysis. Finally, the effects of 2-OHOA treatment on the place escape aversion paradigm (PEAP) and the open-field-induced anxiety test were tested at 21 days following nerve injury compared with vehicle-treated sham and pregabalin-SNI (30 mg/kg, p.o.) control groups. Oral 2-OHOA significantly reduced ipsilateral mechanical and thermal hypersensitivity up to 7 days after SNI. Additionally 2-OHOA decreased the COX-2/COX-1 ratio in lipopolysaccharide-activated macrophage cells and OX-42 expression within the ipsilateral lumbar spinal dorsal horn 7 days after SNI. 2-OHOA significantly restored inner-zone exploration in the open-field test compared with the vehicle-treated sham group at 21 days after SNI. Oral administration of the modified omega 9 fatty acid, 2-OHOA, mediates antinociception and prevents open-field-induced anxiety in the SNI model in Wistar rats, which is mediated by an inhibition of spinal dorsal horn microglia activation. © 2014 European Pain Federation - EFIC®

Nerve Cross-Bridging to Enhance Nerve Regeneration in a Rat Model of Delayed Nerve Repair

Science.gov (United States)

2015-01-01

There are currently no available options to promote nerve regeneration through chronically denervated distal nerve stumps. Here we used a rat model of delayed nerve repair asking of prior insertion of side-to-side cross-bridges between a donor tibial (TIB) nerve and a recipient denervated common peroneal (CP) nerve stump ameliorates poor nerve regeneration. First, numbers of retrogradely-labelled TIB neurons that grew axons into the nerve stump within three months, increased with the size of the perineurial windows opened in the TIB and CP nerves. Equal numbers of donor TIB axons regenerated into CP stumps either side of the cross-bridges, not being affected by target neurotrophic effects, or by removing the perineurium to insert 5-9 cross-bridges. Second, CP nerve stumps were coapted three months after inserting 0-9 cross-bridges and the number of 1) CP neurons that regenerated their axons within three months or 2) CP motor nerves that reinnervated the extensor digitorum longus (EDL) muscle within five months was determined by counting and motor unit number estimation (MUNE), respectively. We found that three but not more cross-bridges promoted the regeneration of axons and reinnervation of EDL muscle by all the CP motoneurons as compared to only 33% regenerating their axons when no cross-bridges were inserted. The same 3-fold increase in sensory nerve regeneration was found. In conclusion, side-to-side cross-bridges ameliorate poor regeneration after delayed nerve repair possibly by sustaining the growth-permissive state of denervated nerve stumps. Such autografts may be used in human repair surgery to improve outcomes after unavoidable delays. PMID:26016986

The cortical representation of sensory inputs arising from bone.

Science.gov (United States)

Ivanusic, Jason J; Sahai, Vineet; Mahns, David A

2009-05-07

In the present study, we show that sensory information from bone reaches the discriminative areas of the somatosensory cortices by electrically stimulating the nerve to the cat humerus and recording evoked potentials on the surface of the primary (SI) and secondary (SII) somatosensory cortex. The SI focus was located over the rostral part of the postcruciate cortex, caudal to the lateral aspect of the cruciate sulcus. The SII focus was identified on the anterior ectosylvian gyrus, lateral to the suprasylvian sulcus. These foci were located adjacent to, or within areas that responded to stimulation of the median, ulnar and/or musculocutaneous nerves. The latency (6-11 ms) to onset of cortical responses in SI and SII were indistinguishable (unpaired t-test; P>0.05), and were consistent with activation of A delta fibers in the peripheral nerve. The amplitudes of the cortical responses were graded as a function of stimulus intensity, and may reflect a mechanism for intensity coding. We did not observe long latency cortical responses (50-300 ms) that would be consistent with C fiber activation in the peripheral nerve, and provide evidence that this may be attributable to inhibition of cortical responsiveness following the initial A delta response. Our finding of discrete, short latency evoked potentials (presumably of A delta origin) in the primary and secondary somatosensory cortices, following stimulation of a nerve innervating bone, may reflect a mechanism for the discriminative component of bone pain.

The visceromotor and somatic afferent nerves of the penis.

Science.gov (United States)

Diallo, Djibril; Zaitouna, Mazen; Alsaid, Bayan; Quillard, Jeanine; Ba, Nathalie; Allodji, Rodrigue Sètchéou; Benoit, Gérard; Bedretdinova, Dina; Bessede, Thomas

2015-05-01

Innervation of the penis supports erectile and sensory functions. This article aims to study the efferent autonomic (visceromotor) and afferent somatic (sensory) nervous systems of the penis and to investigate how these systems relate to vascular pathways. Penises obtained from five adult cadavers were studied via computer-assisted anatomic dissection (CAAD). The number of autonomic and somatic nerve fibers was compared using the Kruskal-Wallis test. Proximally, penile innervation was mainly somatic in the extra-albugineal sector and mainly autonomic in the intracavernosal sector. Distally, both sectors were almost exclusively supplied by somatic nerve fibers, except the intrapenile vascular anastomoses that accompanied both somatic and autonomic (nitrergic) fibers. From this point, the neural immunolabeling within perivascular nerve fibers was mixed (somatic labeling and autonomic labeling). Accessory afferent, extra-albugineal pathways supplied the outer layers of the penis. There is a major change in the functional type of innervation between the proximal and distal parts of the intracavernosal sector of the penis. In addition to the pelvis and the hilum of the penis, the intrapenile neurovascular routes are the third level where the efferent autonomic (visceromotor) and the afferent somatic (sensory) penile nerve fibers are close. Intrapenile neurovascular pathways define a proximal penile segment, which guarantees erectile rigidity, and a sensory distal segment. © 2015 International Society for Sexual Medicine.

Optogenetically enhanced axon regeneration: motor versus sensory neuron-specific stimulation.

Science.gov (United States)

Ward, Patricia J; Clanton, Scott L; English, Arthur W

2018-02-01

Brief neuronal activation in injured peripheral nerves is both necessary and sufficient to enhance motor axon regeneration, and this effect is specific to the activated motoneurons. It is less clear whether sensory neurons respond in a similar manner to neuronal activation following peripheral axotomy. Further, it is unknown to what extent enhancement of axon regeneration with increased neuronal activity relies on a reflexive interaction within the spinal circuitry. We used mouse genetics and optical tools to evaluate the precision and selectivity of system-specific neuronal activation to enhance axon regeneration in a mixed nerve. We evaluated sensory and motor axon regeneration in two different mouse models expressing the light-sensitive cation channel, channelrhodopsin (ChR2). We selectively activated either sensory or motor axons using light stimulation combined with transection and repair of the sciatic nerve. Regardless of genotype, the number of ChR2-positive neurons whose axons had regenerated successfully was greater following system-specific optical treatment, with no effect on the number of ChR2-negative neurons (whether motor or sensory neurons). We conclude that acute system-specific neuronal activation is sufficient to enhance both motor and sensory axon regeneration. This regeneration-enhancing effect is likely cell autonomous. © 2018 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Ulnar nerve entrapment in Guyon's canal due to a lipoma.

Science.gov (United States)

Ozdemir, O; Calisaneller, T; Gerilmez, A; Gulsen, S; Altinors, N

2010-09-01

Guyon's canal syndrome is an ulnar nerve entrapment at the wrist or palm that can cause motor, sensory or combined motor and sensory loss due to various factors . In this report, we presented a 66-year-old man admitted to our clinic with a history of intermittent pain in the left palm and numbness in 4th and 5th finger for two years. His neurological examination revealed a sensory impairment in the right fifth finger. Also, physical examination displayed a subcutaneous mobile soft tissue in ulnar side of the wrist. Electromyographic examination confirmed the diagnosis of type-1 Guyon's canal syndrome. Under axillary blockage, a lipoma compressing the ulnar nerve was excised totally and ulnar nerve was decompressed. The symptoms were improved after the surgery and patient was symptom free on 3rd postoperative week.

Systemic Chemical Desensitization of Peptidergic Sensory Neurons with Resiniferatoxin Inhibits Experimental Periodontitis

Science.gov (United States)

Breivik, Torbjørn; Gundersen, Yngvar; Gjermo, Per; Fristad, Inge; Opstad, Per Kristian

2011-01-01

Background and objective: The immune system is an important player in the pathophysiology of periodontitis. The brain controls immune responses via neural and hormonal pathways, and brain-neuro-endocrine dysregulation may be a central determinant for pathogenesis. Our current knowledge also emphasizes the central role of sensory nerves. In line with this, we wanted to investigate how desensitization of peptidergic sensory neurons influences the progression of ligature-induced periodontitis, and, furthermore, how selected cytokine and stress hormone responses to Gram-negative bacterial lipopolysaccharide (LPS) stimulation are affected. Material and methods: Resiniferatoxin (RTX; 50 μg/kg) or vehicle was injected subcutaneously on days 1, 2, and 3 in stress high responding and periodontitis-susceptible Fischer 344 rats. Periodontitis was induced 2 days thereafter. Progression of the disease was assessed after the ligatures had been in place for 20 days. Two h before decapitation all rats received LPS (150 μg/kg i.p.) to induce a robust immune and stress response. Results: Desensitization with RTX significantly reduced bone loss as measured by digital X-rays. LPS provoked a significantly higher increase in serum levels of the pro-inflammatory cytokine tumour necrosis factor (TNF)-α, but lower serum levels of the anti-inflammatory cytokine interleukin (IL)-10 and the stress hormone corticosterone. Conclusions: In this model RTX-induced chemical desensitization of sensory peptidergic neurons attenuated ligature-induced periodontitis and promoted a shift towards stronger pro-inflammatory cytokine and weaker stress hormone responses to LPS. The results may partly be explained by the attenuated transmission of immuno-inflammatory signals to the brain. In turn, this may weaken the anti-inflammatory brain-derived pathways. PMID:21339860

Sensory feedback in upper limb prosthetics.

Science.gov (United States)

Antfolk, Christian; D'Alonzo, Marco; Rosén, Birgitta; Lundborg, Göran; Sebelius, Fredrik; Cipriani, Christian

2013-01-01

One of the challenges facing prosthetic designers and engineers is to restore the missing sensory function inherit to hand amputation. Several different techniques can be employed to provide amputees with sensory feedback: sensory substitution methods where the recorded stimulus is not only transferred to the amputee, but also translated to a different modality (modality-matched feedback), which transfers the stimulus without translation and direct neural stimulation, which interacts directly with peripheral afferent nerves. This paper presents an overview of the principal works and devices employed to provide upper limb amputees with sensory feedback. The focus is on sensory substitution and modality matched feedback; the principal features, advantages and disadvantages of the different methods are presented.

Implications of Sensory Stimulation in Self-Destructive Behavior.

Science.gov (United States)

Edelson, Stephen M.

1984-01-01

The author extends the self stimulatory theory of self destructive behavior in autistic, schizophrenic, and mentally retarded individuals to suggest that damage of the skin's nerve structure lowers the tactile sensory threshold for physical input and enables individuals to obtain sensory stimulation by repeatedly depressing the damaged area. (CL)

Assessment of nerve regeneration across nerve allografts treated with tacrolimus.

Science.gov (United States)

Haisheng, Han; Songjie, Zuo; Xin, Li

2008-01-01

Although regeneration of nerve allotransplant is a major concern in the clinic, there have been few papers quantitatively assessing functional recovery of animals' nerve allografts in the long term. In this study, functional recovery, histopathological study, and immunohistochemistry changes of rat nerve allograft with FK506 were investigated up to 12 weeks without slaughtering. C57 and SD rats were used for transplantation. The donor's nerve was sliced and transplanted into the recipient. The sciatic nerve was epineurally sutured with 10-0 nylon. In total, 30 models of transplantation were performed and divided into 3 groups that were either treated with FK506 or not. Functional recovery of the grafted nerve was serially assessed by the pin click test, walking track analysis and electrophysiological evaluations. A histopathological study and immunohistochemistry study were done in the all of the models. Nerve allografts treated with FK506 have no immune rejection through 12 weeks. Sensibility had similarly improved in both isografts and allografts. There has been no difference in each graft. Walk track analysis demonstrates significant recovery of motor function of the nerve graft. No histological results of difference were found up to 12 weeks in each graft. In the rodent nerve graft model, FK506 prevented nerve allograft rejection across a major histocompatibility barrier. Sensory recovery seems to be superior to motor function. Nerve isograft and allograft treated with FK506 have no significant difference in function recovery, histopathological result, and immunohistochemistry changes.

A comparative analysis of the encapsulated end-organs of mammalian skeletal muscles and of their sensory nerve endings.

Science.gov (United States)

Banks, R W; Hulliger, M; Saed, H H; Stacey, M J

2009-06-01

The encapsulated sensory endings of mammalian skeletal muscles are all mechanoreceptors. At the most basic functional level they serve as length sensors (muscle spindle primary and secondary endings), tension sensors (tendon organs), and pressure or vibration sensors (lamellated corpuscles). At a higher functional level, the differing roles of individual muscles in, for example, postural adjustment and locomotion might be expected to be reflected in characteristic complements of the various end-organs, their sensory endings and afferent nerve fibres. This has previously been demonstrated with regard to the number of muscle-spindle capsules; however, information on the other types of end-organ, as well as the complements of primary and secondary endings of the spindles themselves, is sporadic and inconclusive regarding their comparative provision in different muscles. Our general conclusion that muscle-specific variability in the provision of encapsulated sensory endings does exist demonstrates the necessity for the acquisition of more data of this type if we are to understand the underlying adaptive relationships between motor control and the structure and function of skeletal muscle. The present quantitative and comparative analysis of encapsulated muscle afferents is based on teased, silver-impregnated preparations. We begin with a statistical analysis of the number and distribution of muscle-spindle afferents in hind-limb muscles of the cat, particularly tenuissimus. We show that: (i) taking account of the necessity for at least one primary ending to be present, muscles differ significantly in the mean number of additional afferents per spindle capsule; (ii) the frequency of occurrence of spindles with different sensory complements is consistent with a stochastic, rather than deterministic, developmental process; and (iii) notwithstanding the previous finding, there is a differential distribution of spindles intramuscularly such that the more complex ones tend

Is distal motor and/or sensory demyelination a distinctive feature of anti-MAG neuropathy?

Science.gov (United States)

Lozeron, Pierre; Ribrag, Vincent; Adams, David; Brisset, Marion; Vignon, Marguerite; Baron, Marine; Malphettes, Marion; Theaudin, Marie; Arnulf, Bertrand; Kubis, Nathalie

2016-09-01

To report the frequency of the different patterns of sensory and motor electrophysiological demyelination distribution in patients with anti-MAG neuropathy in comparison with patients with IgM neuropathy without MAG reactivity (IgM-NP). Thirty-five anti-MAG patients at early disease stage (20.1 months) were compared to 23 patients with IgM-NP; 21 CIDP patients and 13 patients with CMT1a neuropathy were used as gold standard neuropathies with multifocal and homogeneous demyelination, respectively. In all groups, standard motor and sensory electrophysiological parameters, terminal latency index and modified F ratio were investigated. Motor electrophysiological demyelination was divided in four profiles: distal, homogeneous, proximal, and proximo-distal. Distal sensory and sensorimotor demyelination were evaluated. Anti-MAG neuropathy is a demyelinating neuropathy in 91 % of cases. In the upper limbs, reduced TLI is more frequent in anti-MAG neuropathy, compared to IgM-NP. But, predominant distal demyelination of the median nerve is encountered in only 43 % of anti-MAG neuropathy and is also common in IgM-NP (35 %). Homogeneous demyelination was the second most frequent pattern (31 %). Concordance of electrophysiological profiles across motor nerves trunks is low and median nerve is the main site of distal motor conduction slowing. Reduced sensory conduction velocities occurs in 14 % of patients without evidence of predominant distal slowing. Simultaneous sensory and motor distal slowing was more common in the median nerve of anti-MAG neuropathy than IgM-NP. Electrophysiological distal motor demyelination and sensory demyelination are not a distinctive feature of anti-MAG reactivity. In anti-MAG neuropathy it is mainly found in the median nerve suggesting a frequent nerve compression at wrist.

Imaging of the facial nerve

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Veillon, F. [Service de Radiologie I, Hopital de Hautepierre, 67098 Strasbourg Cedex (France)], E-mail: Francis.Veillon@chru-strasbourg.fr; Ramos-Taboada, L.; Abu-Eid, M. [Service de Radiologie I, Hopital de Hautepierre, 67098 Strasbourg Cedex (France); Charpiot, A. [Service d' ORL, Hopital de Hautepierre, 67098 Strasbourg Cedex (France); Riehm, S. [Service de Radiologie I, Hopital de Hautepierre, 67098 Strasbourg Cedex (France)

2010-05-15

The facial nerve is responsible for the motor innervation of the face. It has a visceral motor function (lacrimal, submandibular, sublingual glands and secretion of the nose); it conveys a great part of the taste fibers, participates to the general sensory of the auricle (skin of the concha) and the wall of the external auditory meatus. The facial mimic, production of tears, nasal flow and salivation all depend on the facial nerve. In order to image the facial nerve it is mandatory to be knowledgeable about its normal anatomy including the course of its efferent and afferent fibers and about relevant technical considerations regarding CT and MR to be able to achieve high-resolution images of the nerve.

In Search of an Effective in vivo Reactivator for Organophosphorus Nerve Agent-Inhibited Acetylcholinesterase in the Central Nervous System

Science.gov (United States)

2012-01-01

nerve agents, such as sarin (GB), cyclosarin (GF), and VX, are potent inhibitors of the enzyme cholinesterase (ChE). Their toxic effects are due to...three nerve agents. Keywords: acetylcholinesterase; brain; cholinesterase inhibition; cholinesterase reactivation; cyclosarin; diacetylmonoxime...attributed, at least in part, to nuclophilic impedance [Ekstrom et al., 2006a; b; Hoskovcova et al., 2007]. Other AChE- inhibitors , such as soman, become

Peripheral nerve conduits: technology update

Science.gov (United States)

Arslantunali, D; Dursun, T; Yucel, D; Hasirci, N; Hasirci, V

2014-01-01

Peripheral nerve injury is a worldwide clinical problem which could lead to loss of neuronal communication along sensory and motor nerves between the central nervous system (CNS) and the peripheral organs and impairs the quality of life of a patient. The primary requirement for the treatment of complete lesions is a tension-free, end-to-end repair. When end-to-end repair is not possible, peripheral nerve grafts or nerve conduits are used. The limited availability of autografts, and drawbacks of the allografts and xenografts like immunological reactions, forced the researchers to investigate and develop alternative approaches, mainly nerve conduits. In this review, recent information on the various types of conduit materials (made of biological and synthetic polymers) and designs (tubular, fibrous, and matrix type) are being presented. PMID:25489251

Analysis of human acellular nerve allograft reconstruction of 64 injured nerves in the hand and upper extremity: a 3 year follow-up study.

Science.gov (United States)

Zhu, Shuang; Liu, Jianghui; Zheng, Canbin; Gu, Liqiang; Zhu, Qingtang; Xiang, Jianping; He, Bo; Zhou, Xiang; Liu, Xiaolin

2017-08-01

Human acellular nerve allografts have been increasingly applied in clinical practice. This study was undertaken to investigate the functional outcomes of nerve allograft reconstruction for nerve defects in the upper extremity. A total of 64 patients from 13 hospitals were available for this follow-up study after nerve repair using human acellular nerve allografts. Sensory and motor recovery was examined according to the international standards for motor and sensory nerve recovery. Subgroup analysis and logistic regression analysis were conducted to identify the relationship between the known factors and the outcomes of nerve repair. Mean follow-up time was 355 ± 158 (35-819) days; mean age was 35 ± 11 (14-68) years; average nerve gap length was 27 ± 13 (10-60) mm; no signs of infection, tissue rejection or extrusion were observed among the patients; 48/64 (75%) repaired nerves experienced meaningful recovery. Univariate analysis showed that site and gap length significantly influenced prognosis after nerve repair using nerve grafts. Delay had a marginally significant relationship with the outcome. A multivariate logistic regression model revealed that gap length was an independent predictor of nerve repair using human acellular nerve allografts. The results indicated that the human acellular nerve allograft facilitated safe and effective nerve reconstruction for nerve gaps 10-60 mm in length in the hand and upper extremity. Factors such as site and gap length had a statistically significant influence on the outcomes of nerve allograft reconstruction. Gap length was an independent predictor of nerve repair using human acellular nerve allografts. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Vascularization of the dorsal root ganglia and peripheral nerve of the mouse: Implications for chemical-induced peripheral sensory neuropathies

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Melemedjian Ohannes K

2008-03-01

Full Text Available Abstract Although a variety of industrial chemicals, as well as several chemotherapeutic agents used to treat cancer or HIV, preferentially induce a peripheral sensory neuropathy what remains unclear is why these agents induce a sensory vs. a motor or mixed neuropathy. Previous studies have shown that the endothelial cells that vascularize the dorsal root ganglion (DRG, which houses the primary afferent sensory neurons, are unique in that they have large fenestrations and are permeable to a variety of low and high molecular weight agents. In the present report we used whole-mount preparations, immunohistochemistry, and confocal laser scanning microscopy to show that the cell body-rich area of the L4 mouse DRG has a 7 fold higher density of CD31+ capillaries than cell fiber rich area of the DRG or the distal or proximal aspect of the sciatic nerve. This dense vascularization, coupled with the high permeability of these capillaries, may synergistically contribute, and in part explain, why many potentially neurotoxic agents preferentially accumulate and injure cells within the DRG. Currently, cancer survivors and HIV patients constitute the largest and most rapidly expanding groups that have chemically induced peripheral sensory neuropathy. Understanding the unique aspects of the vascularization of the DRG and closing the endothelial fenestrations of the rich vascular bed of capillaries that vascularize the DRG before intravenous administration of anti-neoplastic or anti-HIV therapies, may offer a mechanism based approach to attenuate these chemically induced peripheral neuropathies in these patients.

Stimuli of Sensory-Motor Nerves Terminate Arterial Contractile Effects of Endothelin-1 by CGRP and Dissociation of ET-1/ETA-Receptor Complexes

Science.gov (United States)

Meens, Merlijn J. P. M. T.; Compeer, Matthijs G.; Hackeng, Tilman M.; van Zandvoort, Marc A.; Janssen, Ben J. A.; De Mey, Jo G. R.

2010-01-01

Background Endothelin-1 (ET-1), a long-acting paracrine mediator, is implicated in cardiovascular diseases but clinical trials with ET-receptor antagonists were not successful in some areas. We tested whether the quasi-irreversible receptor-binding of ET-1 (i) limits reversing effects of the antagonists and (ii) can be selectively dissociated by an endogenous counterbalancing mechanism. Methodology/Principal findings In isolated rat mesenteric resistance arteries, ETA-antagonists, endothelium-derived relaxing factors and synthetic vasodilators transiently reduced contractile effects of ET-1 but did not prevent persistent effects of the peptide. Stimuli of peri-vascular vasodilator sensory-motor nerves such as capsaicin not only reduced but also terminated long-lasting effects of ET-1. This was prevented by CGRP-receptor antagonists and was mimicked by exogenous calcitonin gene-related peptide (CGRP). Using 2-photon laser scanning microscopy in vital intact arteries, capsaicin and CGRP, but not ETA-antagonism, were observed to promote dissociation of pre-existing ET-1/ETA-receptor complexes. Conclusions Irreversible binding and activation of ETA-receptors by ET-1 (i) occur at an antagonist-insensitive site of the receptor and (ii) are selectively terminated by endogenously released CGRP. Hence, natural stimuli of sensory-motor nerves that stimulate release of endogenous CGRP can be considered for therapy of diseases involving ET-1. PMID:20532232

Spontaneous temporal changes and variability of peripheral nerve conduction analyzed using a random effects model

DEFF Research Database (Denmark)

Krøigård, Thomas; Gaist, David; Otto, Marit

2014-01-01

SUMMARY: The reproducibility of variables commonly included in studies of peripheral nerve conduction in healthy individuals has not previously been analyzed using a random effects regression model. We examined the temporal changes and variability of standard nerve conduction measures in the leg...... reexamined after 2 and 26 weeks. There was no change in the variables except for a minor decrease in sural nerve sensory action potential amplitude and a minor increase in tibial nerve minimal F-wave latency. Reproducibility was best for peroneal nerve distal motor latency and motor conduction velocity......, sural nerve sensory conduction velocity, and tibial nerve minimal F-wave latency. Between-subject variability was greater than within-subject variability. Sample sizes ranging from 21 to 128 would be required to show changes twice the magnitude of the spontaneous changes observed in this study. Nerve...

Stability and selectivity of a chronic, multi-contact cuff electrode for sensory stimulation in human amputees.

Science.gov (United States)

Tan, Daniel W; Schiefer, Matthew A; Keith, Michael W; Anderson, J Robert; Tyler, Dustin J

2015-04-01

Stability and selectivity are important when restoring long-term, functional sensory feedback in individuals with limb-loss. Our objective is to demonstrate a chronic, clinical neural stimulation system for providing selective sensory response in two upper-limb amputees. Multi-contact cuff electrodes were implanted in the median, ulnar, and radial nerves of the upper-limb. Nerve stimulation produced a selective sensory response on 19 of 20 contacts and 16 of 16 contacts in subjects 1 and 2, respectively. Stimulation elicited multiple, distinct percept areas on the phantom and residual limb. Consistent threshold, impedance, and percept areas have demonstrated that the neural interface is stable for the duration of this on-going, chronic study. We have achieved selective nerve response from multi-contact cuff electrodes by demonstrating characteristic percept areas and thresholds for each contact. Selective sensory response remains consistent in two upper-limb amputees for 1 and 2 years, the longest multi-contact sensory feedback system to date. Our approach demonstrates selectivity and stability can be achieved through an extraneural interface, which can provide sensory feedback to amputees.

Factors that influence peripheral nerve regeneration

DEFF Research Database (Denmark)

Krarup, Christian; Archibald, Simon J; Madison, Roger D

2002-01-01

median nerve lesions (n = 46) in nonhuman primates over 3 to 4 years, a time span comparable with such lesions in humans. Nerve gap distances of 5, 20, or 50mm were repaired with nerve grafts or collagen-based nerve guide tubes, and three electrophysiological outcome measures were followed: (1) compound...... muscle action potentials in the abductor pollicis brevis muscle, (2) the number and size of motor units in reinnervated muscle, and (3) compound sensory action potentials from digital nerve. A statistical model was used to assess the influence of three variables (repair type, nerve gap distance, and time...... to earliest muscle reinnervation) on the final recovery of the outcome measures. Nerve gap distance and the repair type, individually and concertedly, strongly influenced the time to earliest muscle reinnervation, and only time to reinnervation was significant when all three variables were included as outcome...

Hereditary sensory ataxic neuropathy associated with proximal muscle weakness in the lower extremities.

Science.gov (United States)

Murakami, Tatsufumi; Fukai, Yuta; Rikimaru, Mitsue; Henmi, Shoji; Ohsawa, Yutaka; Sunada, Yoshihide

2010-04-15

We describe three patients from the same family with hereditary sensory ataxic neuropathy followed by proximal muscle weakness in the lower extremities. Sensory ataxic gait began as an initial symptom when patients were in their 50s. Mild proximal weakness in the lower extremities appeared several years later. Serum creatine kinase was mildly elevated. Nerve conduction studies revealed sensory dominant axonal neuropathy, and short sensory evoked potentials showed involvement of the sensory nerve axon, dorsal root ganglia and posterior funiculus of the spinal cord. Needle electromyography showed fibrillation, positive sharp waves, and multiple giant motor unit potentials, suggesting the involvement of anterior horn motor neurons or the anterior root. Autosomal recessive inheritance was considered, because of consanguinity. The disorder described here may be a new clinical entity with unique clinical manifestations. Copyright 2009 Elsevier B.V. All rights reserved.

Hereditary motor and sensory neuropathy-russe: new autosomal recessive neuropathy in Balkan Gypsies.

Science.gov (United States)

Thomas, P K; Kalaydjieva, L; Youl, B; Rogers, T; Angelicheva, D; King, R H; Guergueltcheva, V; Colomer, J; Lupu, C; Corches, A; Popa, G; Merlini, L; Shmarov, A; Muddle, J R; Nourallah, M; Tournev, I

2001-10-01

A novel peripheral neuropathy of autosomal recessive inheritance has been identified in Balkan Gypsies and termed hereditary motor and sensory neuropathy-Russe (HMSN-R). We investigated 21 affected individuals from 10 families. Distal lower limb weakness began between the ages of 8 and 16 years, upper limb involvement beginning between 10 and 43 years, with an average of 22 years. This progressive disorder led to severe weakness of the lower limbs, generalized in the oldest subject (aged 57 years), and marked distal upper limb weakness. Prominent distal sensory loss involved all modalities, resulting in neuropathic joint degeneration in two instances. All patients showed foot deformity, and most showed hand deformity. Motor nerve conduction velocity was moderately reduced in the upper limbs but unobtainable in the legs. Sensory nerve action potentials were absent. There was loss of larger myelinated nerve fibers and profuse regenerative activity in the sural nerve. HMSN-R is a new form of autosomal recessive inherited HMSN caused by a single founder mutation in a 1 Mb interval on chromosome 10q.

Sensorimotor peripheral nerve function and physical activity in older men

DEFF Research Database (Denmark)

Lange-Maia, B. S.; Cauley, J A; Newman, Anne B

2016-01-01

We determined whether sensorimotor peripheral nerve (PN) function was associated with physical activity (PA) in older men. The Osteoporotic Fractures in Men Study Pittsburgh, PA, site (n = 328, age 78.8 ± 4.7 years) conducted PN testing, including: peroneal motor and sural sensory nerve conduction...... (latencies, amplitudes: CMAP and SNAP for motor and sensory amplitude, respectively), 1.4g/10g monoflament (dorsum of the great toe), and neuropathy symptoms. ANOVA and multivariate linear regression modeled PN associations with PA (Physical Activity Scale for the Elderly [PASE] and SenseWear Armband). After...

Differential effects of myostatin deficiency on motor and sensory axons.

Science.gov (United States)

Jones, Maria R; Villalón, Eric; Northcutt, Adam J; Calcutt, Nigel A; Garcia, Michael L

2017-12-01

Deletion of myostatin in mice (MSTN -/- ) alters structural properties of peripheral axons. However, properties like axon diameter and myelin thickness were analyzed in mixed nerves, so it is unclear whether loss of myostatin affects motor, sensory, or both types of axons. Using the MSTN -/- mouse model, we analyzed the effects of increasing the number of muscle fibers on axon diameter, myelin thickness, and internode length in motor and sensory axons. Axon diameter and myelin thickness were increased in motor axons of MSTN -/- mice without affecting internode length or axon number. The number of sensory axons was increased without affecting their structural properties. These results suggest that motor and sensory axons establish structural properties by independent mechanisms. Moreover, in motor axons, instructive cues from the neuromuscular junction may play a role in co-regulating axon diameter and myelin thickness, whereas internode length is established independently. Muscle Nerve 56: E100-E107, 2017. © 2017 Wiley Periodicals, Inc.

Co-cultures provide a new tool to probe communication between adult sensory neurons and urothelium.

Science.gov (United States)

O'Mullane, Lauren M; Keast, Janet R; Osborne, Peregrine B

2013-08-01

Recent evidence suggests that the urothelium functions as a sensory transducer of chemical, mechanical or thermal stimuli and signals to nerve terminals and other cells in the bladder wall. The cellular and molecular basis of neuro-urothelial communication is not easily studied in the intact bladder. This led us to establish a method of co-culturing dorsal root ganglion sensory neurons and bladder urothelial cells. Sensory neurons and urothelial cells obtained from dorsal root ganglia and bladders dissected from adult female Sprague-Dawley® rats were isolated by enzyme treatment and mechanical dissociation. They were plated together or separately on collagen coated substrate and cultured in keratinocyte medium for 48 to 72 hours. Retrograde tracer labeling was performed to identify bladder afferents used for functional testing. Neurite growth and complexity in neurons co-cultured with urothelial cells was increased relative to that in neuronal monocultures. The growth promoting effect of urothelial cells was reduced by the tyrosine kinase inhibitor K252a but upstream inhibition of nerve growth factor signaling with TrkA-Fc had no effect. Fura-2 calcium imaging of urothelial cells showed responses to adenosine triphosphate (100 μM) and activation of TRPV4 (4α-PDD, 10 μM) but not TRPV1 (capsaicin, 1 μM), TRPV3 (farnesyl pyrophosphate, 1 μM) or TRPA1 (mustard oil, 100 μM). In contrast, co-cultured neurons were activated by all agonists except farnesyl pyrophosphate. Co-culturing provides a new methodology for investigating neuro-urothelial interactions in animal models of urological conditions. Results suggest that neuronal properties are maintained in the presence of urothelium and neurite growth is potentiated by a nerve growth factor independent mechanism. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Injury of the Inferior Alveolar Nerve during Implant Placement: a Literature Review

Directory of Open Access Journals (Sweden)

Gintaras Juodzbalys

2011-01-01

Full Text Available Objectives: The purpose of present article was to review aetiological factors, mechanism, clinical symptoms, and diagnostic methods as well as to create treatment guidelines for the management of inferior alveolar nerve injury during dental implant placement.Material and Methods: Literature was selected through a search of PubMed, Embase and Cochrane electronic databases. The keywords used for search were inferior alveolar nerve injury, inferior alveolar nerve injuries, inferior alveolar nerve injury implant, inferior alveolar nerve damage, inferior alveolar nerve paresthesia and inferior alveolar nerve repair. The search was restricted to English language articles, published from 1972 to November 2010. Additionally, a manual search in the major anatomy, dental implant, periodontal and oral surgery journals and books were performed. The publications there selected by including clinical, human anatomy and physiology studies.Results: In total 136 literature sources were obtained and reviewed. Aetiological factors of inferior alveolar nerve injury, risk factors, mechanism, clinical sensory nerve examination methods, clinical symptoms and treatment were discussed. Guidelines were created to illustrate the methods used to prevent and manage inferior alveolar nerve injury before or after dental implant placement.Conclusions: The damage of inferior alveolar nerve during the dental implant placement can be a serious complication. Clinician should recognise and exclude aetiological factors leading to nerve injury. Proper presurgery planning, timely diagnosis and treatment are the key to avoid nerve sensory disturbances management.

Long-term improvements in sensory inhibition with gestational choline supplementation linked to α7 nicotinic receptors through studies in Chrna7 null mutation mice.

Science.gov (United States)

Stevens, Karen E; Choo, Kevin S; Stitzel, Jerry A; Marks, Michael J; Adams, Catherine E

2014-03-13

Perinatal choline supplementation has produced several benefits in rodent models, from improved learning and memory to protection from the behavioral effects of fetal alcohol exposure. We have shown that supplemented choline through gestation and lactation produces long-term improvement in deficient sensory inhibition in DBA/2 mice which models a similar deficit in schizophrenia patients. The present study extends that research by feeding normal or supplemented choline diets to DBA/2 mice carrying the null mutation for the α7 nicotinic receptor gene (Chrna7). DBA/2 mice heterozygotic for Chrna7 were bred together. Dams were placed on supplemented (5 gm/kg diet) or normal (1.1 gm/kg diet) choline at mating and remained on the specific diet until offspring weaning. Thereafter, offspring were fed standard rodent chow. Adult offspring were assessed for sensory inhibition. Brains were obtained to ascertain hippocampal α7 nicotinic receptor levels. Choline-supplemented mice heterozygotic or null-mutant for Chrna7 failed to show improvement in sensory inhibition. Only wildtype choline-supplemented mice showed improvement with the effect solely through a decrease in test amplitude. This supports the hypothesis that gestational-choline supplementation is acting through the α7 nicotinic receptor to improve sensory inhibition. Although there was a significant gene-dose-related change in hippocampal α7 receptor numbers, binding studies did not reveal any choline-dose-related change in binding in any hippocampal region, the interaction being driven by a significant genotype main effect (wildtype>heterozygote>null mutant). These data parallel a human study wherein the offspring of pregnant women receiving choline supplementation during gestation, showed better sensory inhibition than offspring of women on placebo. Published by Elsevier B.V.

Cranial nerves III, IV and VI

International Nuclear Information System (INIS)

Laine, I.J.; Smoker, W.R.; Kuta, A.J.; Felton, W.L.

1991-01-01

Because of advances in CT and MR imaging, accurate identification and evaluation of cranial nerve lesions is now possible. Cranial nerves III, IV, and VI, providing motor and sensory control of the eye, can be evaluated as a unit. In this paper, the authors present an overview of the anatomy and pathology of these cranial nerves. We first illustrate their normal anatomic pathways from the brain stem to the orbit. This is followed by clinical examples of patients with a variety of isolated and complex palsies of these three cranial nerves. This is accomplished by inclusion of ocular photographs, correlative imaging studies, and the use of diagrams. Knowledge of the gross and imaging anatomy and the ophthalmologic manifestations of pathology affecting these three cranial nerves permits a tailored approach to their evaluation

Diffuse noxious inhibitory controls and nerve injury: restoring an imbalance between descending monoamine inhibitions and facilitations.

Science.gov (United States)

Bannister, Kirsty; Patel, Ryan; Goncalves, Leonor; Townson, Louisa; Dickenson, Anthony H

2015-09-01

Diffuse noxious inhibitory controls (DNICs) utilize descending inhibitory controls through poorly understood brain stem pathways. The human counterpart, conditioned pain modulation, is reduced in patients with neuropathy aligned with animal data showing a loss of descending inhibitory noradrenaline controls together with a gain of 5-HT3 receptor-mediated facilitations after neuropathy. We investigated the pharmacological basis of DNIC and whether it can be restored after neuropathy. Deep dorsal horn neurons were activated by von Frey filaments applied to the hind paw, and DNIC was induced by a pinch applied to the ear in isoflurane-anaesthetized animals. Spinal nerve ligation was the model of neuropathy. Diffuse noxious inhibitory control was present in control rats but abolished after neuropathy. α2 adrenoceptor mechanisms underlie DNIC because the antagonists, yohimbine and atipamezole, markedly attenuated this descending inhibition. We restored DNIC in spinal nerve ligated animals by blocking 5-HT3 descending facilitations with the antagonist ondansetron or by enhancing norepinephrine modulation through the use of reboxetine (a norepinephrine reuptake inhibitor, NRI) or tapentadol (μ-opioid receptor agonist and NRI). Additionally, ondansetron enhanced DNIC in normal animals. Diffuse noxious inhibitory controls are reduced after peripheral nerve injury illustrating the central impact of neuropathy, leading to an imbalance in descending excitations and inhibitions. Underlying noradrenergic mechanisms explain the relationship between conditioned pain modulation and the use of tapentadol and duloxetine (a serotonin, NRI) in patients. We suggest that pharmacological strategies through manipulation of the monoamine system could be used to enhance DNIC in patients by blocking descending facilitations with ondansetron or enhancing norepinephrine inhibitions, so possibly reducing chronic pain.

Glomerular nerve endings in corial papillae of the pig lip skin.

Science.gov (United States)

Malinovský, L; Pác, L; Krivánková, L

1982-01-01

In the tops of corial papillae of the pig lip skin the authors sometimes observed besides typical sensory corpuscles also glomerular nerve endings. They are formed by one axon or they are polyaxon. The nerve fibres are richly branched in the formation. In electronogrammes a large number of axons is visible in cross sections round some of which there are more or less formed lamellous systems up to four lamellae. Between the axons there are nuclei of Schwann cells, on the surface there is a thin capsule of fibrocyte character. In non-primate mammals the typical receptor in the corium of the skin are simple corpuscles, in primates glomerular nerve endings. As concerns sensory corpuscles it is the other way round. The authors are of the opinion that the observed glomerular endings represent morphologically a transitory formation. With respect to the occurrence of lamellous complexes in the glomeruli, they can be considered as equivalent to simple sensory corpuscles with rapid adaptation.

Cognitive mechanisms associated with auditory sensory gating

Science.gov (United States)

Jones, L.A.; Hills, P.J.; Dick, K.M.; Jones, S.P.; Bright, P.

2016-01-01

Sensory gating is a neurophysiological measure of inhibition that is characterised by a reduction in the P50 event-related potential to a repeated identical stimulus. The objective of this work was to determine the cognitive mechanisms that relate to the neurological phenomenon of auditory sensory gating. Sixty participants underwent a battery of 10 cognitive tasks, including qualitatively different measures of attentional inhibition, working memory, and fluid intelligence. Participants additionally completed a paired-stimulus paradigm as a measure of auditory sensory gating. A correlational analysis revealed that several tasks correlated significantly with sensory gating. However once fluid intelligence and working memory were accounted for, only a measure of latent inhibition and accuracy scores on the continuous performance task showed significant sensitivity to sensory gating. We conclude that sensory gating reflects the identification of goal-irrelevant information at the encoding (input) stage and the subsequent ability to selectively attend to goal-relevant information based on that previous identification. PMID:26716891

Pre-differentiation of mesenchymal stromal cells in combination with a microstructured nerve guide supports peripheral nerve regeneration in the rat sciatic nerve model.

Science.gov (United States)

Boecker, Arne Hendrik; van Neerven, Sabien Geraldine Antonia; Scheffel, Juliane; Tank, Julian; Altinova, Haktan; Seidensticker, Katrin; Deumens, Ronald; Tolba, Rene; Weis, Joachim; Brook, Gary Anthony; Pallua, Norbert; Bozkurt, Ahmet

2016-02-01

Many bioartificial nerve guides have been investigated pre-clinically for their nerve regeneration-supporting function, often in comparison to autologous nerve transplantation, which is still regarded as the current clinical gold standard. Enrichment of these scaffolds with cells intended to support axonal regeneration has been explored as a strategy to boost axonal regeneration across these nerve guides Ansselin et al. (1998). In the present study, 20 mm rat sciatic nerve defects were implanted with a cell-seeded microstructured collagen nerve guide (Perimaix) or an autologous nerve graft. Under the influence of seeded, pre-differentiated mesenchymal stromal cells, axons regenerated well into the Perimaix nerve guide. Myelination-related parameters, like myelin sheath thickness, benefitted from an additional seeding with pre-differentiated mesenchymal stromal cells. Furthermore, both the number of retrogradely labelled sensory neurons and the axon density within the implant were elevated in the cell-seeded scaffold group with pre-differentiated mesenchymal stromal cells. However, a pre-differentiation had no influence on functional recovery. An additional cell seeding of the Perimaix nerve guide with mesenchymal stromal cells led to an extent of functional recovery, independent of the differentiation status, similar to autologous nerve transplantation. These findings encourage further investigations on pre-differentiated mesenchymal stromal cells as a cellular support for peripheral nerve regeneration. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Stimuli of sensory-motor nerves terminate arterial contractile effects of endothelin-1 by CGRP and dissociation of ET-1/ET(A-receptor complexes.

Directory of Open Access Journals (Sweden)

Merlijn J P M T Meens

Full Text Available BACKGROUND: Endothelin-1 (ET-1, a long-acting paracrine mediator, is implicated in cardiovascular diseases but clinical trials with ET-receptor antagonists were not successful in some areas. We tested whether the quasi-irreversible receptor-binding of ET-1 (i limits reversing effects of the antagonists and (ii can be selectively dissociated by an endogenous counterbalancing mechanism. METHODOLOGY/PRINCIPAL FINDINGS: In isolated rat mesenteric resistance arteries, ET(A-antagonists, endothelium-derived relaxing factors and synthetic vasodilators transiently reduced contractile effects of ET-1 but did not prevent persistent effects of the peptide. Stimuli of peri-vascular vasodilator sensory-motor nerves such as capsaicin not only reduced but also terminated long-lasting effects of ET-1. This was prevented by CGRP-receptor antagonists and was mimicked by exogenous calcitonin gene-related peptide (CGRP. Using 2-photon laser scanning microscopy in vital intact arteries, capsaicin and CGRP, but not ET(A-antagonism, were observed to promote dissociation of pre-existing ET-1/ET(A-receptor complexes. CONCLUSIONS: Irreversible binding and activation of ET(A-receptors by ET-1 (i occur at an antagonist-insensitive site of the receptor and (ii are selectively terminated by endogenously released CGRP. Hence, natural stimuli of sensory-motor nerves that stimulate release of endogenous CGRP can be considered for therapy of diseases involving ET-1.

Nerve Regeneration: Understanding Biology and Its Influence on Return of Function After Nerve Transfers.

Science.gov (United States)

Gordon, Tessa

2016-05-01

Poor functional outcomes are frequent after peripheral nerve injuries despite the regenerative support of Schwann cells. Motoneurons and, to a lesser extent, sensory neurons survive the injuries but outgrowth of axons across the injury site is slow. The neuronal regenerative capacity and the support of regenerating axons by the chronically denervated Schwann cells progressively declines with time and distance of the injury from the denervated targets. Strategies, including brief low-frequency electrical stimulation that accelerates target reinnervation and functional recovery, and the insertion of cross-bridges between a donor nerve and a recipient denervated nerve stump, are effective in promoting functional outcomes after complete and incomplete injuries. Copyright © 2016 Elsevier Inc. All rights reserved.

Sympathetic vasoconstrictor nerve function in alcoholic neuropathy

DEFF Research Database (Denmark)

Jensen, K; Andersen, K; Smith, T

1984-01-01

(18% and 48% decrease respectively). However, in three patients with moderate neuropathy, and in one patient with no signs of neuropathy, this veno-arteriolar reflex was absent, indicating dysfunction of the peripheral sympathetic adrenergic nerve fibres. The three patients also showed a lesser degree......The peripheral sympathetic vasomotor nerve function was investigated in 18 male chronic alcoholics admitted for intellectual impairment or polyneuropathy. By means of the local 133Xenon washout technique, the sympathetic veno-arteriolar axon-reflex was studied. This normally is responsible for a 50...... comprise not only the peripheral sensory and motor nerve fibres, but also the thin pseudomotor and vasomotor nerves....

Regulation of early and delayed radiation responses in rat small intestine by capsaicin-sensitive nerves

International Nuclear Information System (INIS)

Wang Junru; Zheng Huaien; Kulkarni, Ashwini; Ou Xuemei; Hauer-Jensen, Martin

2006-01-01

Purpose: Mast cells protect against the early manifestations of intestinal radiation toxicity, but promote chronic intestinal wall fibrosis. Intestinal sensory nerves are closely associated with mast cells, both anatomically and functionally, and serve an important role in the regulation of mucosal homeostasis. This study examined the effect of sensory nerve ablation on the intestinal radiation response in an established rat model. Methods and Materials: Rats underwent sensory nerve ablation with capsaicin or sham ablation. Two weeks later, a localized segment of ileum was X-irradiated or sham irradiated. Structural, cellular, and molecular changes were examined 2 weeks (early injury) and 26 weeks (chronic injury) after irradiation. The mast cell dependence of the effect of sensory nerve ablation on intestinal radiation injury was assessed using c-kit mutant (Ws/Ws) mast cell-deficient rats. Results: Capsaicin treatment caused a baseline reduction in mucosal mast cell density, crypt cell proliferation, and expression of substance P and calcitonin gene-related peptide, two neuropeptides released by sensory neurons. Sensory nerve ablation strikingly exacerbated early intestinal radiation toxicity (loss of mucosal surface area, inflammation, intestinal wall thickening), but attenuated the development of chronic intestinal radiation fibrosis (collagen I accumulation and transforming growth factor β immunoreactivity). In mast cell-deficient rats, capsaicin treatment exacerbated postradiation epithelial injury (loss of mucosal surface area), but none of the other aspects of radiation injury were affected by capsaicin treatment. Conclusions: Ablation of capsaicin-sensitive enteric neurons exacerbates early intestinal radiation toxicity, but attenuates development of chronic fibroproliferative changes. The effect of capsaicin treatment on the intestinal radiation response is partly mast cell dependent

Intraglomerular inhibition shapes the strength and temporal structure of glomerular output.

Science.gov (United States)

Shao, Zuoyi; Puche, Adam C; Liu, Shaolin; Shipley, Michael T

2012-08-01

Odor signals are transmitted to the olfactory bulb by olfactory nerve (ON) synapses onto mitral/tufted cells (MCs) and external tufted cells (ETCs). ETCs, in turn, provide feedforward excitatory input to MCs. MC and ETCs are also regulated by inhibition: intraglomerular and interglomerular inhibitory circuits act at MC and ETC apical dendrites; granule cells (GCs) inhibit MC lateral dendrites via the MC→GC→MC circuit. We investigated the contribution of intraglomerular inhibition to MC and ETCs responses to ON input. ON input evokes initial excitation followed by early, strongly summating inhibitory postsynaptic currents (IPSCs) in MCs; this is followed by prolonged, intermittent IPSCs. The N-methyl-d-aspartate receptor antagonist dl-amino-5-phosphovaleric acid, known to suppress GABA release by GCs, reduced late IPSCs but had no effect on early IPSCs. In contrast, selective intraglomerular block of GABA(A) receptors eliminated all early IPSCs and caused a 5-fold increase in ON-evoked MC spiking and a 10-fold increase in response duration. ETCs also receive intraglomerular inhibition; blockade of inhibition doubled ETC spike responses. By reducing ETC excitatory drive and directly inhibiting MCs, intraglomerular inhibition is a key factor shaping the strength and temporal structure of MC responses to sensory input. Sensory input generates an intraglomerular excitation-inhibition sequence that limits MC spike output to a brief temporal window. Glomerular circuits may dynamically regulate this input-output window to optimize MC encoding across sniff-sampled inputs.

Peripheral site ligand conjugation to a non-quaternary oxime enhances reactivation of nerve agent-inhibited human acetylcholinesterase

NARCIS (Netherlands)

Koning, M.C. de; Grol, M. van; Noort, D.

2011-01-01

Commonly employed pyridinium-oxime (charged) reactivators of nerve agent inhibited acetylcholinesterase (AChE) do not readily pass the blood brain barrier (BBB) because of the presence of charge(s). Conversely, non-ionic oxime reactivators often suffer from a lack of reactivating potency due to a

Hereditary sensory and autonomic neuropathy type IID caused by an SCN9A mutation.

Science.gov (United States)

Yuan, Junhui; Matsuura, Eiji; Higuchi, Yujiro; Hashiguchi, Akihiro; Nakamura, Tomonori; Nozuma, Satoshi; Sakiyama, Yusuke; Yoshimura, Akiko; Izumo, Shuji; Takashima, Hiroshi

2013-04-30

To identify the clinical features of Japanese patients with suspected hereditary sensory and autonomic neuropathy (HSAN) on the basis of genetic diagnoses. On the basis of clinical, in vivo electrophysiologic, and pathologic findings, 9 Japanese patients with sensory and autonomic nervous dysfunctions were selected. Eleven known HSAN disease-causing genes and 5 related genes were screened using a next-generation sequencer. A homozygous mutation, c.3993delGinsTT, was identified in exon 22 of SCN9A from 2 patients/families. The clinical phenotype was characterized by adolescent or congenital onset with loss of pain and temperature sensation, autonomic nervous dysfunctions, hearing loss, and hyposmia. Subsequently, this mutation was discovered in one of patient 1's sisters, who also exhibited sensory and autonomic nervous system dysfunctions, with recurrent fractures being the most predominant feature. Nerve conduction studies revealed definite asymmetric sensory nerve involvement in patient 1. In addition, sural nerve pathologic findings showed loss of large myelinated fibers in patient 1, whereas the younger patient showed normal sural nerve pathology. We identified a novel homozygous mutation in SCN9A from 2 Japanese families with autosomal recessive HSAN. This loss-of-function SCN9A mutation results in disturbances in the sensory, olfactory, and autonomic nervous systems. We propose that SCN9A mutation results in the new entity of HSAN type IID, with additional symptoms including hyposmia, hearing loss, bone dysplasia, and hypogeusia.

Ulnar nerve sonography in leprosy neuropathy.

Science.gov (United States)

Wang, Zhu; Liu, Da-Yue; Lei, Yang-Yang; Yang, Zheng; Wang, Wei

2016-01-01

A 23-year-old woman presented with a half-year history of right forearm sensory and motor dysfunction. Ultrasound imaging revealed definite thickening of the right ulnar nerve trunk and inner epineurium, along with heterogeneous hypoechogenicity and unclear nerve fiber bundle. Color Doppler exhibited a rich blood supply, which was clearly different from the normal ulnar nerve presentation with a scarce blood supply. The patient subsequently underwent needle aspiration of the right ulnar nerve, and histopathological examination confirmed that granulomatous nodules had formed with a large number of infiltrating lymphocytes and a plurality of epithelioid cells in the fibrous connective tissues, with visible atypical foam cells and proliferous vascularization, consistent with leprosy. Our report will familiarize readers with the characteristic sonographic features of the ulnar nerve in leprosy, particularly because of the decreasing incidence of leprosy in recent years.

Sensory experience regulates cortical inhibition by inducing IGF1 in VIP neurons.

Science.gov (United States)

Mardinly, A R; Spiegel, I; Patrizi, A; Centofante, E; Bazinet, J E; Tzeng, C P; Mandel-Brehm, C; Harmin, D A; Adesnik, H; Fagiolini, M; Greenberg, M E

2016-03-17

Inhibitory neurons regulate the adaptation of neural circuits to sensory experience, but the molecular mechanisms by which experience controls the connectivity between different types of inhibitory neuron to regulate cortical plasticity are largely unknown. Here we show that exposure of dark-housed mice to light induces a gene program in cortical vasoactive intestinal peptide (VIP)-expressing neurons that is markedly distinct from that induced in excitatory neurons and other subtypes of inhibitory neuron. We identify Igf1 as one of several activity-regulated genes that are specific to VIP neurons, and demonstrate that IGF1 functions cell-autonomously in VIP neurons to increase inhibitory synaptic input onto these neurons. Our findings further suggest that in cortical VIP neurons, experience-dependent gene transcription regulates visual acuity by activating the expression of IGF1, thus promoting the inhibition of disinhibitory neurons and affecting inhibition onto cortical pyramidal neurons.

Evaluation and use of regenerative multi electrode interfaces in peripheral nerves

Science.gov (United States)

Desai, Vidhi

Peripheral nerves offer unique accessibility to the innate motor and sensory pathways that can be interfaced with high degree of selectivity for intuitive and bidirectional control of advanced upper extremity prosthetic limbs. Several peripheral nerve interfaces have been proposed and investigated over the last few decades with significant progress made in the area of sensory feedback. However, clinical translation still remains a formidable challenge due to the lack of long term recordings. Prominent causes include signal degradation, eventual interface failures, and lack of specificity in the low amplitude nerve signals. This dissertation evaluates the capabilities of the newly developed Regenerative Multi-electrode Interface (REMI) by the characterization of signal quality progression, the identification of interfaced axon types, and the demonstration of "functional linkage" between acquired signals and target organs. Chapter 2 details the chronic recording of high quality signals from REMI in sciatic nerve which remained stable over a 120 day implantation period indicative of minimal ongoing tissue response with no detrimental effects on the recording ability. The dominant cause of failures was attributable to abiotic factors pertaining to the connector/wire breakage, observed in 76% of REMI implants. Also, the REMI implants had 20% higher success rate and significantly larger Signal to Noise Ratio (SNR) in comparison to the Utah Slanted Electrode Array (USEA). Chapter 3 describes the successful feasibility of interfacing with motor and sensory axons by REMI implantation in the tibial and sural fascicles of the sciatic nerve. A characteristic sampling bias towards recording signals from medium-to-large diameter axons that are primarily involved in mechanoception and proprioception sensory functions was uncovered. Specific bursting units (Inter Spike Interval of 30-70ms) were observed most frequently from the tibial fascicle during bipedal locomotion. Chapter 4

Right-sided vagus nerve stimulation inhibits induced spinal cord seizures.

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Tubbs, R Shane; Salter, E George; Killingsworth, Cheryl; Rollins, Dennis L; Smith, William M; Ideker, Raymond E; Wellons, John C; Blount, Jeffrey P; Oakes, W Jerry

2007-01-01

We have previously shown that left-sided vagus nerve stimulation results in cessation of induced spinal cord seizures. To test our hypothesis that right-sided vagus nerve stimulation will also abort seizure activity, we have initiated seizures in the spinal cord and then performed right-sided vagus nerve stimulation in an animal model. Four pigs were anesthetized and placed in the lateral position and a small laminectomy performed in the lumbar region. Topical penicillin, a known epileptogenic drug to the cerebral cortex and spinal cord, was next applied to the dorsal surface of the exposed cord. With the exception of the control animal, once seizure activity was discernible via motor convulsion or increased electrical activity, the right vagus nerve previously isolated in the neck was stimulated. Following multiple stimulations of the vagus nerve and with seizure activity confirmed, the cord was transected in the midthoracic region and vagus nerve stimulation performed. Right-sided vagus nerve stimulation resulted in cessation of spinal cord seizure activity in all animals. Transection of the spinal cord superior to the site of seizure induction resulted in the ineffectiveness of vagus nerve stimulation in causing cessation of seizure activity in all study animals. As with left-sided vagus nerve stimulation, right-sided vagus nerve stimulation results in cessation of induced spinal cord seizures. Additionally, the effects of right-sided vagus nerve stimulation on induced spinal cord seizures involve descending spinal pathways. These data may aid in the development of alternative mechanisms for electrical stimulation for patients with medically intractable seizures and add to our knowledge regarding the mechanism for seizure cessation following peripheral nerve stimulation.

Silicone Molding and Lifetime Testing of Peripheral Nerve Interfaces for Neuroprostheses

Energy Technology Data Exchange (ETDEWEB)

Gupte, Kimaya [Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Biomedical Engineering; Tolosa, Vanessa [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Center for Micro- and Nanotechnology

2016-08-10

Implantable peripheral nerve cuffs have a large application in neuroprostheses as they can be used to restore sensation to those with upper limb amputations. Modern day prosthetics, while lessening the pain associated with phantom limb syndrome, have limited fine motor control and do not provide sensory feedback to patients. Sensory feedback with prosthetics requires communication between the nervous system and limbs, and is still a challenge to accomplish with amputees. Establishing this communication between the peripheral nerves in the arm and artificial limbs is vital as prosthetics research aims to provide sensory feedback to amputees. Peripheral nerve cuffs restore sensation by electrically stimulating certain parts of the nerve in order to create feeling in the hand. Cuff electrodes have an advantage over standard electrodes as they have high selective stimulation by bringing the electrical interface close to the neural tissue in order to selectively activate targeted regions of a peripheral nerve. In order to further improve the selective stimulation of these nerve cuffs, there is need for finer spatial resolution among electrodes. One method to achieve a higher spatial resolution is to increase the electrode density on the cuff itself. Microfabrication techniques can be used to achieve this higher electrode density. Using L-Edit, a layout editor, microfabricated peripheral nerve cuffs were designed with a higher electrode density than the current model. This increase in electrode density translates to an increase in spatial resolution by at least one order of magnitude. Microfabricated devices also have two separate components that are necessary to understand before implantation: lifetime of the device and assembly to prevent nerve damage. Silicone molding procedures were optimized so that devices do not damage nerves in vivo, and lifetime testing was performed on test microfabricated devices to determine their lifetime in vivo. Future work of this project

Toxicity to sensory neurons and Schwann cells in experimental linezolid-induced peripheral neuropathy.

Science.gov (United States)

Bobylev, Ilja; Maru, Helina; Joshi, Abhijeet R; Lehmann, Helmar C

2016-03-01

Peripheral neuropathy is a common side effect of prolonged treatment with linezolid. This study aimed to explore injurious effects of linezolid on cells of the peripheral nervous system and to establish in vivo and in vitro models of linezolid-induced peripheral neuropathy. C57BL/6 mice were treated with linezolid or vehicle over a total period of 4 weeks. Animals were monitored by weight, nerve conduction studies and behavioural tests. Neuropathic changes were assessed by morphometry on sciatic nerves and epidermal nerve fibre density in skin sections. Rodent sensory neuron and Schwann cell cultures were exposed to linezolid in vitro and assessed for mitochondrial dysfunction. Prolonged treatment with linezolid induced a mild, predominantly small sensory fibre neuropathy in vivo. Exposure of Schwann cells and sensory neurons to linezolid in vitro caused mitochondrial dysfunction primarily in neurons (and less prominently in Schwann cells). Sensory axonopathy could be partially prevented by co-administration of the Na(+)/Ca(2+) exchanger blocker KB-R7943. Clinical and pathological features of linezolid-induced peripheral neuropathy can be replicated in in vivo and in vitro models. Mitochondrial dysfunction may contribute to the axonal damage to sensory neurons that occurs after linezolid exposure. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Functional evaluation of peripheral nerve regeneration and target reinnervation in animal models: a critical overview.

Science.gov (United States)

Navarro, Xavier

2016-02-01

Peripheral nerve injuries usually lead to severe loss of motor, sensory and autonomic functions in the patients. Due to the complex requirements for adequate axonal regeneration, functional recovery is often poorly achieved. Experimental models are useful to investigate the mechanisms related to axonal regeneration and tissue reinnervation, and to test new therapeutic strategies to improve functional recovery. Therefore, objective and reliable evaluation methods should be applied for the assessment of regeneration and function restitution after nerve injury in animal models. This review gives an overview of the most useful methods to assess nerve regeneration, target reinnervation and recovery of complex sensory and motor functions, their values and limitations. The selection of methods has to be adequate to the main objective of the research study, either enhancement of axonal regeneration, improving regeneration and reinnervation of target organs by different types of nerve fibres, or increasing recovery of complex sensory and motor functions. It is generally recommended to use more than one functional method for each purpose, and also to perform morphological studies of the injured nerve and the reinnervated targets. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Imaging the trigeminal nerve

International Nuclear Information System (INIS)

Borges, Alexandra; Casselman, Jan

2010-01-01

Of all cranial nerves, the trigeminal nerve is the largest and the most widely distributed in the supra-hyoid neck. It provides sensory input from the face and motor innervation to the muscles of mastication. In order to adequately image the full course of the trigeminal nerve and its main branches a detailed knowledge of neuroanatomy and imaging technique is required. Although the main trunk of the trigeminal nerve is consistently seen on conventional brain studies, high-resolution tailored imaging is mandatory to depict smaller nerve branches and subtle pathologic processes. Increasing developments in imaging technique made possible isotropic sub-milimetric images and curved reconstructions of cranial nerves and their branches and led to an increasing recognition of symptomatic trigeminal neuropathies. Whereas MRI has a higher diagnostic yield in patients with trigeminal neuropathy, CT is still required to demonstrate the bony anatomy of the skull base and is the modality of choice in the context of traumatic injury to the nerve. Imaging of the trigeminal nerve is particularly cumbersome as its long course from the brainstem nuclei to the peripheral branches and its rich anastomotic network impede, in most cases, a topographic approach. Therefore, except in cases of classic trigeminal neuralgia, in which imaging studies can be tailored to the root entry zone, the full course of the trigeminal nerve has to be imaged. This article provides an update in the most recent advances on MR imaging technique and a segmental imaging approach to the most common pathologic processes affecting the trigeminal nerve.

Imaging the trigeminal nerve

Energy Technology Data Exchange (ETDEWEB)

Borges, Alexandra [Radiology Department, Instituto Portugues de Oncologia Francisco Gentil, Centro de Lisboa, Rua Prof. Lima Basto, 1093, Lisboa (Portugal)], E-mail: borgalexandra@gmail.com; Casselman, Jan [Department of Radiology, A. Z. St Jan Brugge and A. Z. St Augustinus Antwerpen Hospitals (Belgium)

2010-05-15

Of all cranial nerves, the trigeminal nerve is the largest and the most widely distributed in the supra-hyoid neck. It provides sensory input from the face and motor innervation to the muscles of mastication. In order to adequately image the full course of the trigeminal nerve and its main branches a detailed knowledge of neuroanatomy and imaging technique is required. Although the main trunk of the trigeminal nerve is consistently seen on conventional brain studies, high-resolution tailored imaging is mandatory to depict smaller nerve branches and subtle pathologic processes. Increasing developments in imaging technique made possible isotropic sub-milimetric images and curved reconstructions of cranial nerves and their branches and led to an increasing recognition of symptomatic trigeminal neuropathies. Whereas MRI has a higher diagnostic yield in patients with trigeminal neuropathy, CT is still required to demonstrate the bony anatomy of the skull base and is the modality of choice in the context of traumatic injury to the nerve. Imaging of the trigeminal nerve is particularly cumbersome as its long course from the brainstem nuclei to the peripheral branches and its rich anastomotic network impede, in most cases, a topographic approach. Therefore, except in cases of classic trigeminal neuralgia, in which imaging studies can be tailored to the root entry zone, the full course of the trigeminal nerve has to be imaged. This article provides an update in the most recent advances on MR imaging technique and a segmental imaging approach to the most common pathologic processes affecting the trigeminal nerve.

Anomalous Innervation of the Median Nerve in the Arm in the Absence of the Musculocutaneous Nerve

Directory of Open Access Journals (Sweden)

Khursheed Raza

2017-03-01

Full Text Available The brachial plexus innervates the upper extremities. While variations in the formation of the brachial plexus and its terminal branches are quite common, it is uncommon for the median nerve to innervate the muscles of the arm. During the dissection of an elderly male cadaver at the Department of Anatomy, All India Institute of Medical Sciences, New Delhi, India, in 2016, the coracobrachialis muscle was found to be supplied by a direct branch from the lateral root of the median nerve and the musculocutaneous nerve was absent. The branches of the median nerve supplied the biceps brachii and brachialis muscles and the last branch continued as the lateral cutaneous nerve of the forearm. These variations may present atypically in cases of arm flexor paralysis or sensory loss on the lateral forearm. Knowledge of these variations is important in surgeries and during the administration of regional anaesthesia near the shoulder joint and upper arm.

Nerve conduction in relation to vibration exposure - a non-positive cohort study

Directory of Open Access Journals (Sweden)

Nilsson Tohr

2010-07-01

Full Text Available Abstract Background Peripheral neuropathy is one of the principal clinical disorders in workers with hand-arm vibration syndrome. Electrophysiological studies aimed at defining the nature of the injury have provided conflicting results. One reason for this lack of consistency might be the sparsity of published longitudinal etiological studies with both good assessment of exposure and a well-defined measure of disease. Against this background we measured conduction velocities in the hand after having assessed vibration exposure over 21 years in a cohort of manual workers. Methods The study group consisted of 155 male office and manual workers at an engineering plant that manufactured pulp and paper machinery. The study has a longitudinal design regarding exposure assessment and a cross-sectional design regarding the outcome of nerve conduction. Hand-arm vibration dose was calculated as the product of self-reported occupational exposure, collected by questionnaire and interviews, and the measured or estimated hand-arm vibration exposure in 1987, 1992, 1997, 2002, and 2008. Distal motor latencies in median and ulnar nerves and sensory nerve conduction over the carpal tunnel and the finger-palm segments in the median nerve were measured in 2008. Before the nerve conduction measurement, the subjects were systemically warmed by a bicycle ergometer test. Results There were no differences in distal latencies between subjects exposed to hand-arm vibration and unexposed subjects, neither in the sensory conduction latencies of the median nerve, nor in the motor conduction latencies of the median and ulnar nerves. Seven subjects (9% in the exposed group and three subjects (12% in the unexposed group had both pathological sensory nerve conduction at the wrist and symptoms suggestive of carpal tunnel syndrome. Conclusion Nerve conduction measurements of peripheral hand nerves revealed no exposure-response association between hand-arm vibration exposure and

Role of Netrin-1 Signaling in Nerve Regeneration

Directory of Open Access Journals (Sweden)

Xin-Peng Dun

2017-02-01

Full Text Available Netrin-1 was the first axon guidance molecule to be discovered in vertebrates and has a strong chemotropic function for axonal guidance, cell migration, morphogenesis and angiogenesis. It is a secreted axon guidance cue that can trigger attraction by binding to its canonical receptors Deleted in Colorectal Cancer (DCC and Neogenin or repulsion through binding the DCC/Uncoordinated (Unc5 A–D receptor complex. The crystal structures of Netrin-1/receptor complexes have recently been revealed. These studies have provided a structure based explanation of Netrin-1 bi-functionality. Netrin-1 and its receptor are continuously expressed in the adult nervous system and are differentially regulated after nerve injury. In the adult spinal cord and optic nerve, Netrin-1 has been considered as an inhibitor that contributes to axon regeneration failure after injury. In the peripheral nervous system, Netrin-1 receptors are expressed in Schwann cells, the cell bodies of sensory neurons and the axons of both motor and sensory neurons. Netrin-1 is expressed in Schwann cells and its expression is up-regulated after peripheral nerve transection injury. Recent studies indicated that Netrin-1 plays a positive role in promoting peripheral nerve regeneration, Schwann cell proliferation and migration. Targeting of the Netrin-1 signaling pathway could develop novel therapeutic strategies to promote peripheral nerve regeneration and functional recovery.

Streptozocin-induced type-1 diabetes mellitus results in decreased density of CGRP sensory and TH sympathetic nerve fibers that are positively correlated with bone loss at the mouse femoral neck.

Science.gov (United States)

Enríquez-Pérez, Iris A; Galindo-Ordoñez, Karla E; Pantoja-Ortíz, Christian E; Martínez-Martínez, Arisaí; Acosta-González, Rosa I; Muñoz-Islas, Enriqueta; Jiménez-Andrade, Juan M

2017-08-10

Type-1 diabetes mellitus (T1DM) results in loss of innervation in some tissues including epidermis and retina; however, the effect on bone innervation is unknown. Likewise, T1DM results in pathological bone loss and increased risk of fracture. Thus, we quantified the density of calcitonin gene-related peptide (CGRP + ) sensory and tyrosine hydroxylase (TH + ) sympathetic nerve fibers and determined the association between the innervation density and microarchitecture of trabecular bone at the mouse femoral neck. Ten weeks-old female mice received 5 daily administrations of streptozocin (i.p. 50mg/kg) or citrate (control group). Twenty weeks later, femurs were analyzed by microCT and processed for immunohistochemistry. Confocal microscopy analysis revealed that mice with T1DM had a significant loss of both CGRP + and TH + nerve fibers in the bone marrow at the femoral neck. Likewise, microCT analysis revealed a significant decrease in the trabecular bone mineral density (tBMD), bone volume/total volume ratio (BV/TB), trabecular thickness (Tb.Th), trabecular number (Tb.N) and trabecular separation (Tb.Sp) in mice with T1DM as compared to control mice. Analysis of correlation revealed a positive and significant association between density of CGRP + or TH + nerve fibers with tBMD, BV/TV, Tb.Th and Tb.Sp, but not with trabecular number (there was a positive association only for CGRP + ) and degree of anisotropy (DA). This study suggests an interaction between sensory and sympathetic nervous system and T1DM-induced bone loss. Identification of the factors involved in the loss of CGRP + sensory and TH + sympathetic fibers and how they regulate bone loss may result in new avenues to treat T1DM-related osteoporosis. Copyright © 2017 Elsevier B.V. All rights reserved.

Sensory symptom profiles and co-morbidities in painful radiculopathy.

Directory of Open Access Journals (Sweden)

Friederike Mahn

Full Text Available Painful radiculopathies (RAD and classical neuropathic pain syndromes (painful diabetic polyneuropathy, postherpetic neuralgia show differences how the patients express their sensory perceptions. Furthermore, several clinical trials with neuropathic pain medications failed in painful radiculopathy. Epidemiological and clinical data of 2094 patients with painful radiculopathy were collected within a cross sectional survey (painDETECT to describe demographic data and co-morbidities and to detect characteristic sensory abnormalities in patients with RAD and compare them with other neuropathic pain syndromes. Common co-morbidities in neuropathic pain (depression, sleep disturbance, anxiety do not differ considerably between the three conditions. Compared to other neuropathic pain syndromes touch-evoked allodynia and thermal hyperalgesia are relatively uncommon in RAD. One distinct sensory symptom pattern (sensory profile, i.e., severe painful attacks and pressure induced pain in combination with mild spontaneous pain, mild mechanical allodynia and thermal hyperalgesia, was found to be characteristic for RAD. Despite similarities in sensory symptoms there are two important differences between RAD and other neuropathic pain disorders: (1 The paucity of mechanical allodynia and thermal hyperalgesia might be explained by the fact that the site of the nerve lesion in RAD is often located proximal to the dorsal root ganglion. (2 The distinct sensory profile found in RAD might be explained by compression-induced ectopic discharges from a dorsal root and not necessarily by nerve damage. These differences in pathogenesis might explain why medications effective in DPN and PHN failed to demonstrate efficacy in RAD.

Cold intolerance following median and ulnar nerve injuries : prognosis and predictors

NARCIS (Netherlands)

Ruijs, A.C.J; Jaquet, J-B.; van Riel, W. G.; Daanen, H. A M; Hovius, S.E.R.

This study describes the predictors for cold intolerance and the relationship to sensory recovery after median and ulnar nerve injuries. The study population consisted of 107 patients 2 to 10 years after median, ulnar or combined median and ulnar nerve injuries. Patients were asked to fill out the

Cold intolerance following median and ulnar nerve injuries : prognosis and predictors

NARCIS (Netherlands)

Ruijs, A.C.J.; Jaquet, J.B.; Riel, W.G. van; Daanen, H.A.M.; Hovius, S.E.R.

2007-01-01

This study describes the predictors for cold intolerance and the relationship to sensory recovery after median and ulnar nerve injuries. The study population consisted of 107 patients 2 to 10 years after median, ulnar or combined median and ulnar nerve injuries. Patients were asked to fill out the

Sensorimotor integration in chronic stroke: Baseline differences and response to sensory training.

Science.gov (United States)

Brown, Katlyn E; Neva, Jason L; Feldman, Samantha J; Staines, W Richard; Boyd, Lara A

2018-01-01

The integration of somatosensory information from the environment into the motor cortex to inform movement is essential for motor function. As motor deficits commonly persist into the chronic phase of stroke recovery, it is important to understand potential contributing factors to these deficits, as well as their relationship with motor function. To date the impact of chronic stroke on sensorimotor integration has not been thoroughly investigated. The current study aimed to comprehensively examine the influence of chronic stroke on sensorimotor integration, and determine whether sensorimotor integration can be modified with an intervention. Further, it determined the relationship between neurophysiological measures of sensorimotor integration and motor deficits post-stroke. Fourteen individuals with chronic stroke and twelve older healthy controls participated. Motor impairment and function were quantified in individuals with chronic stroke. Baseline neurophysiology was assessed using nerve-based measures (short- and long-latency afferent inhibition, afferent facilitation) and vibration-based measures of sensorimotor integration, which paired vibration with single and paired-pulse TMS techniques. Neurophysiological assessment was performed before and after a vibration-based sensory training paradigm to assess changes within these circuits. Vibration-based, but not nerve-based measures of sensorimotor integration were different in individuals with chronic stroke, as compared to older healthy controls, suggesting that stroke differentially impacts integration of specific types of somatosensory information. Sensorimotor integration was behaviourally relevant in that it related to both motor function and impairment post-stroke. Finally, sensory training modulated sensorimotor integration in individuals with chronic stroke and controls. Sensorimotor integration is differentially impacted by chronic stroke based on the type of afferent feedback. However, both nerve

The role of the oximes HI-6 and HS-6 inside human acetylcholinesterase inhibited with nerve agents: a computational study.

Science.gov (United States)

Cuya, Teobaldo; Gonçalves, Arlan da Silva; da Silva, Jorge Alberto Valle; Ramalho, Teodorico C; Kuca, Kamil; C C França, Tanos

2017-10-27

The oximes 4-carbamoyl-1-[({2-[(E)-(hydroxyimino) methyl] pyridinium-1-yl} methoxy) methyl] pyridinium (known as HI-6) and 3-carbamoyl-1-[({2-[(E)-(hydroxyimino) methyl] pyridinium-1-yl} methoxy) methyl] pyridinium (known as HS-6) are isomers differing from each other only by the position of the carbamoyl group on the pyridine ring. However, this slight difference was verified to be responsible for big differences in the percentual of reactivation of acetylcholinesterase (AChE) inhibited by the nerve agents tabun, sarin, cyclosarin, and VX. In order to try to find out the reason for this, a computational study involving molecular docking, molecular dynamics, and binding energies calculations, was performed on the binding modes of HI-6 and HS-6 on human AChE (HssAChE) inhibited by those nerve agents.

Adductor canal block versus femoral nerve block for analgesia after total knee arthroplasty

DEFF Research Database (Denmark)

Jaeger, Pia; Zaric, Dusanka; Fomsgaard, Jonna Storm

2013-01-01

Femoral nerve block (FNB), a commonly used postoperative pain treatment after total knee arthroplasty (TKA), reduces quadriceps muscle strength essential for mobilization. In contrast, adductor canal block (ACB) is predominately a sensory nerve block. We hypothesized that ACB preserves quadriceps...

Matrix metalloproteinase-2 is downregulated in sciatic nerve by streptozotocin induced diabetes and/or treatment with minocycline: Implications for nerve regeneration

Science.gov (United States)

Ali, Sumia; Driscoll, Heather E.; Newton, Victoria L.; Gardiner, Natalie J.

2014-01-01

Minocycline is an inhibitor of matrix metalloproteinases (MMPs) and has been shown to have analgesic effects. Whilst increased expression of MMPs is associated with neuropathic pain, MMPs also play crucial roles in Wallerian degeneration and nerve regeneration. In this study we examined the expression of MMP-2, MMP-9 and tissue inhibitor of metalloproteinase (TIMP)-1/-2 in the sciatic nerve of control and streptozotocin-induced diabetic rats treated with either vehicle or minocycline by quantitative PCR and gelatin zymography. We assessed the effects of minocycline on nerve conduction velocity and intraepidermal nerve fibre (IENF) deficits in diabetic neuropathy and investigated the effects of minocycline or MMP-2 on neurite outgrowth from primary cultures of dissociated adult rat sensory neurons. We show that MMP-2 is expressed constitutively in the sciatic nerve in vivo and treatment with minocycline or diabetes leads to downregulation of MMP-2 expression and activity. The functional consequence of this is IENF deficits in minocycline-treated nondiabetic rats and an unsupportive microenvironment for regeneration in diabetes. Minocycline reduces levels of MMP-2 mRNA and nerve growth factor-induced neurite outgrowth. Furthermore, in vivo minocycline treatment reduces preconditioning-induced in vitro neurite outgrowth following a sciatic nerve crush. In contrast, the addition of active MMP-2 facilitates neurite outgrowth in the absence of neurotrophic support and pre-treatment of diabetic sciatic nerve substrata with active MMP-2 promotes a permissive environment for neurite outgrowth. In conclusion we suggest that MMP-2 downregulation may contribute to the regenerative deficits in diabetes. Minocycline treatment also downregulates MMP-2 activity and is associated with inhibitory effects on sensory neurons. Thus, caution should be exhibited with its use as the balance between beneficial and detrimental outcomes may be critical in assessing the benefits of using

The nerve endings of the acetabular labrum.

Science.gov (United States)

Kim, Y T; Azuma, H

1995-11-01

The nerve endings of the human acetabular labrum were investigated. Twenty-three acetabular labra were obtained from 24 fresh human cadavers, stained with Suzuki's silver impregnation and an immunohistochemical technique for neurogenic specific protein S-100, and examined by light and electron microscopy. Ramified free nerve endings were seen in all specimens by silver staining, and also were observed by the immunohistochemical technique for S-100 protein. Sensory nerve end organs, such as a Vater-Pacini corpuscle, Golgi-Mazzoni corpuscle, Ruffini corpuscle, and articular corpuscle (Krause corpuscle), were observed by silver staining. Collagen fibers were scattered sparsely in the superficial layer of the labrum, and nerve endings were observed mostly in this region. Collagen fibers were sparse, and nerve endings also were observed in some regions among the collagen fiber bundles in the inner layer. Innervation of the acetabular labrum was confirmed in this study, suggesting that nerve endings in the labrum may be involved in nociceptive and proprioceptive mechanisms.

Unusually large quiescent ancient schwannoma of hypoglossal nerve

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Sangeeta P Wanjari

2013-01-01

Full Text Available Ancient schwannoma is considered as a variant of schwannoma, comprising about 10% of all schwanommas. Schwannoma is a benign neoplasm derived from the nerve sheath of peripheral motor, sensory and sympathetic nerves and from the cranial nerve pairs. It usually presents as a solitary soft-tissue lesion which is slow growing, encapsulated and is often associated with nerve attached peripherally. Diagnosis is often confirmed with the microscopic examination. The long standing schwannoma attributes to degenerative changes and is termed "ancient" schwannoma. Present case is of a 68-year-old female patient who reported with an asymptomatic large swelling below mandible on the left side since last 23 years. The lesion was surgically excised under general anesthesia.

Nerve and muscle involvement in mitochondrial disorders: an electrophysiological study.

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Mancuso, Michelangelo; Piazza, Selina; Volpi, Leda; Orsucci, Daniele; Calsolaro, Valeria; Caldarazzo Ienco, Elena; Carlesi, Cecilia; Rocchi, Anna; Petrozzi, Lucia; Calabrese, Rosanna; Siciliano, Gabriele

2012-04-01

Involvement of the peripheral nervous system in mitochondrial disorders (MD) has been previously reported. However, the exact prevalence of peripheral neuropathy and/or myopathy in MD is still unclear. In order to evaluate the prevalence of neuropathy and myopathy in MD, we performed sensory and motor nerve conduction studies (NCS) and concentric needle electromyography (EMG) in 44 unselected MD patients. NCS were abnormal in 36.4% of cases, and were consistent with a sensori-motor axonal multineuropathy (multifocal neuropathy), mainly affecting the lower limbs. EMG evidence of myopathy was present in 54.5% of patients, again mainly affecting the lower limbs. Nerve and muscle involvement was frequently subclinical. Peripheral nerve and muscle involvement is common in MD patients. Our study supports the variability of the clinical expression of MD. Further studies are needed to better understand the molecular basis underlying the phenotypic variability among MD patients.

Cranial nerves in the Australian lungfish, Neoceratodus forsteri, and in fossil relatives (Osteichthyes: Dipnoi).

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Kemp, A

2017-02-01

Three systems, two sensory and one protective, are present in the skin of the living Australian lungfish, Neoceratodus forsteri, and in fossil lungfish, and the arrangement and innervation of the sense organs is peculiar to lungfish. Peripheral branches of nerves that innervate the sense organs are slender and unprotected, and form before any skeletal structures appear. When the olfactory capsule develops, it traps some of the anterior branches of cranial nerve V, which emerged from the chondrocranium from the lateral sphenotic foramen. Cranial nerve I innervates the olfactory organ enclosed within the olfactory capsule and cranial nerve II innervates the eye. Cranial nerve V innervates the sense organs of the snout and upper lip, and, in conjunction with nerve IX and X, the sense organs of the posterior and lateral head. Cranial nerve VII is primarily a motor nerve, and a single branch innervates sense organs in the mandible. There are no connections between nerves V and VII, although both emerge from the brain close to each other. The third associated system consists of lymphatic vessels covered by an extracellular matrix of collagen, mineralised as tubules in fossils. Innervation of the sensory organs is separate from the lymphatic system and from the tubule system of fossil lungfish. Copyright © 2016 Elsevier Ltd. All rights reserved.

Median nerve fascicular anatomy as a basis for distal neural prostheses.

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Planitzer, Uwe; Steinke, Hanno; Meixensberger, Jürgen; Bechmann, Ingo; Hammer, Niels; Winkler, Dirk

2014-05-01

Functional electrical stimulation (FES) serves as a possible therapy to restore missing motor functions of peripheral nerves by means of cuff electrodes. FES is established for improving lower limb function. Transferring this method to the upper extremity is complex, due to a lack of anatomical data on the physiological configuration of nerve fascicles. Our study's aim was to provide an anatomical basis for FES of the median nerve in the distal forearm and hand. We investigated 21 distal median nerves from 12 body donors. The peripheral fascicles were traced back by removing the external and interfascicular epineurium and then assigned to 4 quadrants. A distinct motor and sensory distribution was observed. The fascicles innervating the thenar eminence and the first lumbrical muscle originated from the nerves' radial parts in 82%. The fascicle supplying the second lumbrical muscle originated from the ulnar side in 78%. No macroscopically visible plexus formation was observed for the distal median nerve in the forearm. The findings on the distribution of the motor branches of the median nerve and the missing plexus formation may likely serve as an anatomical basis for FES of the distal forearm. However, due to the considerable variability of the motor branches, cuff electrodes will need to be adapted individually in FES. Taking into account the sensory distribution of the median nerve, FES may also possibly be applied in the treatment of regional pain syndromes. Copyright © 2013 Elsevier GmbH. All rights reserved.

Detrended fluctuation analysis of compound action potentials re-corded in the cutaneous nerves of diabetic rats

International Nuclear Information System (INIS)

Quiroz-González, Salvador; Rodríguez-Torres, Erika Elizabeth; Segura-Alegría, Bertha; Pereira-Venegas, Javier; Lopez-Gomez, Rosa Estela; Jiménez-Estrada, Ismael

2016-01-01

Highlights: • Fractal analysis of compound action potentials (CAP) evoked in diabetic nerves. • Diabetic rats showed an increment in the chaotic behavior of CAP responses. • Diabetes provokes impaired transmission of sensory information in rats. - Abstract: The electrophysiological alterations in nerves due to diabetes are classically studied in relation to their instantaneous frequency, conduction velocity and amplitude. However, analysis of amplitude variability may reflect the occurrence of feedback loop mechanisms that adjust the output as a function of its previous activity could indicate fractal dynamics. We assume that a peripheral neuropathy, such as that evoked by diabetes, the inability to maintain a steady flow of sensory information is reflected as a breakdown of the long range power-law correlation of CAP area fluctuation from cutaneous nerves. To test this, we first explored in normal rats whether fluctuations in the trial-to-trial CAP area showed a self-similar behavior or fractal structure by means of detrended fluctuations analysis (DFA), and Poincare plots. In addition, we determine whether such CAP fluctuations varied by diabetes induction. Results showed that CAP area fluctuation of SU nerves evoked in normal rats present a long term correlation and self-similar organization (fractal behavior) from trial to trial stimulation as evidenced by DFA of CAP areas. However, CAPs recorded in diabetic nerves exhibited significant reductions in area, larger duration and increased area variability and different Poincare plots than control nerves. The Hurst exponent value determined with the DFA method from a series of 2000 CAPs evoked in diabetic SU nerves was smaller than in control nerves. It is proposed that in cutaneous nerves of normal rats variability of the CAP area present a long term correlation and self-similar organization (fractal behavior), and reflect the ability to maintain a steady flow of sensory information through cutaneous nerves

Sciatic Nerve Injury After Proximal Hamstring Avulsion and Repair.

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Wilson, Thomas J; Spinner, Robert J; Mohan, Rohith; Gibbs, Christopher M; Krych, Aaron J

2017-07-01

Muscle bellies of the hamstring muscles are intimately associated with the sciatic nerve, putting the sciatic nerve at risk of injury associated with proximal hamstring avulsion. There are few data informing the magnitude of this risk, identifying risk factors for neurologic injury, or determining neurologic outcomes in patients with distal sciatic symptoms after surgery. To characterize the frequency and nature of sciatic nerve injury and distal sciatic nerve-related symptoms after proximal hamstring avulsion and to characterize the influence of surgery on these symptoms. Cohort study; Level of evidence, 3. This was a retrospective review of patients with proximal partial or complete hamstring avulsion. The outcome of interest was neurologic symptoms referable to the sciatic nerve distribution below the knee. Neurologic symptoms in operative patients were compared pre- and postoperatively. The cohort consisted of 162 patients: 67 (41.4%) operative and 95 (58.6%) nonoperative. Sciatic nerve-related symptoms were present in 22 operative and 23 nonoperative patients, for a total of 45 (27.8%) patients (8 [4.9%] motor deficits, 11 [6.8%] sensory deficits, and 36 [22.2%] with neuropathic pain). Among the operative cohort, 3 of 3 (100.0%) patients showed improvement in their motor deficit postoperatively, 3 of 4 (75.0%) patients' sensory symptoms improved, and 17 of 19 (89.5%) patients had improvement in pain. A new or worsening deficit occurred in 5 (7.5%) patients postoperatively (2 [3.1%] motor deficits, 1 [1.5%] sensory deficit, and 3 [4.5%] with new pain). Predictors of operative intervention included lower age (odds ratio [OR], 0.952; 95% CI, 0.921-0.982; P = .001) and complete avulsion (OR, 10.292; 95% CI, 2.526-72.232; P hamstring avulsion are underrecognized. Currently, neurologic symptoms are not considered when determining whether to pursue operative intervention. Given the high likelihood of improvement with surgical treatment, neurologic symptoms should be

Prostaglandin E1 in conjunction with high doses of vitamin B12 improves nerve conduction velocity of patients with diabetic peripheral neuropathy

Institute of Scientific and Technical Information of China (English)

Jilai Li; Zhirong Wan

2008-01-01

BACKGROUND: Prostaglandin E1 improves diabetic peripheral neuropathy in symptoms and sensory threshold. Vitamin B1 and methyl-vitamin B12 improve microcirculation to peripheral nerve tissue and promote neurotrophy.OBJECTIVE: To observe motor nerve and sensory nerve conduction velocity in patients with diabetic peripheral neuropathy, prior to and after treatment with prostaglandin E1, vitamin B1 and different doses of vitamin B12.DESIGN, TIME AND SETTING: Randomized, controlled experiment, performed at the Department of Neurology. Beijing Hantian Central Hospital, between February 2002 and September 2007.PARTICIPANTS: A total of 122 patients with type 2 diabetic peripheral neuropathy; 73 males and 49 females were included. All patients met the diagnostic criteria of diabetes mellitus, as determined by the World Health Organization in 1999 and 2006, and also the diagnostic criteria of diabetic peripheral neuropathy. For each subject, conduction disorders in the median nerve and in the common peroneal nerve were observed using electromyogram. Also, after diet and drug treatment, the blood glucose level of subjects was observed to be at a satisfactory level for more than two weeks, and the symptoms of diabetic peripheral neuropathy were not alleviated.METHODS: All patients were randomly divided into the following three groups. A control group (n=40), in which, 100mg vitamin B1 and 500μg vitamin B12 were intramuscularly injected. A vitamin B12 low-dose treated group (n=42), in which 10μg prostaglandin E1 in 250mL physiological saline was intravenously injected once a day and 100mg vitamin B1 and 500μg vitamin B12 was intramuscularly injected once a day. Lastly, a vitamin B12 high-dose treated group (n=40), in which administration was the same as in the vitamin B12 low-dose treated group, except that 500μg vitamin B12 was replaced by 1mg vitamin B12. Administration was performed for four weeks for each group.MAIN OUTCOME MEASURES: The motor nerve and sensory nerve

Disrupted sensory gating in pathological gambling.

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Stojanov, Wendy; Karayanidis, Frini; Johnston, Patrick; Bailey, Andrew; Carr, Vaughan; Schall, Ulrich

2003-08-15

Some neurochemical evidence as well as recent studies on molecular genetics suggest that pathologic gambling may be related to dysregulated dopamine neurotransmission. The current study examined sensory (motor) gating in pathologic gamblers as a putative measure of endogenous brain dopamine activity with prepulse inhibition of the acoustic startle eye-blink response and the auditory P300 event-related potential. Seventeen pathologic gamblers and 21 age- and gender-matched healthy control subjects were assessed. Both prepulse inhibition measures were recorded under passive listening and two-tone prepulse discrimination conditions. Compared to the control group, pathologic gamblers exhibited disrupted sensory (motor) gating on all measures of prepulse inhibition. Sensory motor gating deficits of eye-blink responses were most profound at 120-millisecond prepulse lead intervals in the passive listening task and at 240-millisecond prepulse lead intervals in the two-tone prepulse discrimination task. Sensory gating of P300 was also impaired in pathologic gamblers, particularly at 500-millisecond lead intervals, when performing the discrimination task on the prepulse. In the context of preclinical studies on the disruptive effects of dopamine agonists on prepulse inhibition, our findings suggest increased endogenous brain dopamine activity in pathologic gambling in line with previous neurobiological findings.

Dysregulation of the descending pain system in temporomandibular disorders revealed by low-frequency sensory transcutaneous electrical nerve stimulation: a pupillometric study.

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Annalisa Monaco

Full Text Available Using computerized pupillometry, our previous research established that the autonomic nervous system (ANS is dysregulated in patients suffering from temporomandibular disorders (TMDs, suggesting a potential role for ANS dysfunction in pain modulation and the etiology of TMD. However, pain modulation hypotheses for TMD are still lacking. The periaqueductal gray (PAG is involved in the descending modulation of defensive behavior and pain through μ, κ, and δ opioid receptors. Transcutaneous electrical nerve stimulation (TENS has been extensively used for pain relief, as low-frequency stimulation can activate µ receptors. Our aim was to use pupillometry to evaluate the effect of low-frequency TENS stimulation of μ receptors on opioid descending pathways in TMD patients. In accordance with the Research Diagnostic Criteria for TMD, 18 females with myogenous TMD and 18 matched-controls were enrolled. All subjects underwent subsequent pupillometric evaluations under dark and light conditions before, soon after (end of stimulation and long after (recovery period sensorial TENS. The overall statistics derived from the darkness condition revealed no significant differences in pupil size between cases and controls; indeed, TENS stimulation significantly reduced pupil size in both groups. Controls, but not TMD patients, displayed significant differences in pupil size before compared with after TENS. Under light conditions, TMD patients presented a smaller pupil size compared with controls; the pupil size was reduced only in the controls. Pupil size differences were found before and during TENS and before and after TENS in the controls only. Pupillometry revealed that stimulating the descending opioid pathway with low-frequency sensory TENS of the fifth and seventh pairs of cranial nerves affects the peripheral target. The TMD patients exhibited a different pattern of response to TENS stimulation compared with the controls, suggesting that impaired

Nerve Regeneration Should Be Highly Valued in the Treatment of Diabetic Peripheral Neuropathy

Institute of Scientific and Technical Information of China (English)

LIANG Xiao-chun

2008-01-01

@@ Diabetic peripheral neuropathy (DPN) is the most common chronic complication of the long-term complications of diabetes, affecting up to 90% of patients during the progress of the disease. Many parts of the nerve system, including the sensory nerves, motor nerves and autonomic nerves, can be affected, leading to various clinical features. DPN leads not only to a great degree of mutilation and death but also to the occurrence and development of other long-term complications in diabetics.

Quantitative Sensory Testing and Current Perception Threshold Testing in Patients With Chronic Pain Following Lower Extremity Fracture.

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Griffioen, Mari A; Greenspan, Joel D; Johantgen, Meg; Von Rueden, Kathryn; O'Toole, Robert V; Dorsey, Susan G; Renn, Cynthia L

2018-01-01

Chronic pain is a significant problem for patients with lower extremity injuries. While pain hypersensitivity has been identified in many chronic pain conditions, it is not known whether patients with chronic pain following lower extremity fracture report pain hypersensitivity in the injured leg. To quantify and compare peripheral somatosensory function and sensory nerve activation thresholds in persons with chronic pain following lower extremity fractures with a cohort of persons with no history of lower extremity fractures. This was a cross-sectional study where quantitative sensory testing and current perception threshold testing were conducted on the injured and noninjured legs of cases and both legs of controls. A total of 14 cases and 28 controls participated in the study. Mean time since injury at the time of testing for cases was 22.3 (standard deviation = 12.1) months. The warmth detection threshold ( p = .024) and nerve activation thresholds at 2,000 Hz ( p sensory nerve function at the site of injury in patients with chronic pain following lower extremity fractures using quantitative sensory testing and current perception threshold testing.

Evaluation of dermal myelinated nerve fibers in diabetes mellitus

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Peltier, Amanda C.; Myers, M. Iliza; Artibee, Kay J.; Hamilton, Audra D.; Yan, Qing; Guo, Jiasong; Shi, Yaping; Wang, Lily; Li, Jun

2013-01-01

Skin biopsies have primarily been used to study the non-myelinated nerve fibers of the epidermis in a variety of neuropathies. In the present study, we have expanded the skin biopsy technique to glabrous, non-hairy skin to evaluate myelinated nerve fibers in the most highly prevalent peripheral nerve disease, diabetic polyneuropathy (DPN). Twenty patients with DPN (Type I, n=9; Type II, n=11) and sixteen age-matched healthy controls (ages 29–73) underwent skin biopsy of the index finger, nerve conduction studies, and composite neuropathy scoring. In patients with DPN, we found a statistically significant reduction of both mechanoreceptive Meissner corpuscles (MC) and their afferent myelinated nerve fibers (p=0.01). This myelinated nerve fiber loss was correlated with the decreased amplitudes of sensory/motor responses in nerve conduction studies. This study supports the utilization of skin biopsy to quantitatively evaluate axonal loss of myelinated nerve fibers in patients with DPN. PMID:23781963

A preliminary study of the sensory distribution of the penile dorsal and ventral nerves: implications for effective penile block for circumcision.

LENUS (Irish Health Repository)

Long, Ronan M

2012-01-31

OBJECTIVE: To determine the sensory innervation of the penis, as regional anaesthesia is often used either for postoperative analgesia or as the sole anaesthetic technique for circumcision. Since first described in 1978 the dorsal penile nerve block has become the standard technique, but some blocks are ineffective; a better understanding of the sensory innervation of the penis might improve the efficacy of the dorsal penile block technique. PATIENTS AND METHODS: In 13 men undergoing circumcision with local anaesthetic, cutaneous sensation was tested before and after infiltration of the dorsal aspect of the penis, and then again after infiltration of the ventral aspect. The area of anaesthesia was mapped using pin-prick sensation. RESULTS: Ten of the 13 patients showed a similar pattern of sensory distribution. After the dorsal block, the dorsal aspect of the shaft of the penis and glans penis became insensate. The ventral aspect of the shaft remained sensate up to and including the frenulum. After successful ventral infiltration all sensate areas became insensate and circumcision proceeded. In one case the frenulum and distal ventral foreskin was anaesthetized after the dorsal block and ventral infiltration was not required. No patient experienced pain during circumcision. CONCLUSION: For consistently successful regional anaesthesia of the foreskin in circumcision, a dorsal block must be used. This should be combined with ventral infiltration at the site of incision. This method will avoid inconsistencies and allow pain-free circumcision using local anaesthesia in most men.

Sensory Innervation of the Nonspecialized Connective Tissues in the Low Back of the Rat

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Corey, Sarah M.; Vizzard, Margaret A.; Badger, Gary J.; Langevin, Helene M.

2011-01-01

Chronic musculoskeletal pain, including low back pain, is a worldwide debilitating condition; however, the mechanisms that underlie its development remain poorly understood. Pathological neuroplastic changes in the sensory innervation of connective tissue may contribute to the development of nonspecific chronic low back pain. Progress in understanding such potentially important abnormalities is hampered by limited knowledge of connective tissue's normal sensory innervation. The goal of this study was to evaluate and quantify the sensory nerve fibers terminating within the nonspecialized connective tissues in the low back of the rat. With 3-dimensional reconstructions of thick (30–80 μm) tissue sections we have for the first time conclusively identified sensory nerve fiber terminations within the collagen matrix of connective tissue in the low back. Using dye labeling techniques with Fast Blue, presumptive dorsal root ganglia cells that innervate the low back were identified. Of the Fast Blue-labeled cells, 60–88% also expressed calcitonin gene-related peptide (CGRP) immunoreactivity. Based on the immunolabeling with CGRP and the approximate size of these nerve fibers (≤2 μm) we hypothesize that they are Aδ or C fibers and thus may play a role in the development of chronic pain. PMID:21411968

Effect of high-frequency repetitive transcranial magnetic stimulation on motor cortical excitability and sensory nerve conduction velocity in subacute-stage incomplete spinal cord injury patients.

Science.gov (United States)

Cha, Hyun Gyu; Ji, Sang-Goo; Kim, Myoung-Kwon

2016-07-01

[Purpose] The aim of the present study was to determine whether repetitive transcranial magnetic stimulation can improve sensory recovery of the lower extremities in subacute-stage spinal cord injury patients. [Subjects and Methods] This study was conducted on 20 subjects with diagnosed paraplegia due to spinal cord injury. These 20 subjects were allocated to an experimental group of 10 subjects that underwent active repetitive transcranial magnetic stimulation or to a control group of 10 subjects that underwent sham repetitive transcranial magnetic stimulation. The SCI patients in the experimental group underwent active repetitive transcranial magnetic stimulation and conventional rehabilitation therapy, whereas the spinal cord injury patients in the control group underwent sham repetitive transcranial magnetic stimulation and conventional rehabilitation therapy. Participants in both groups received therapy five days per week for six-weeks. Latency, amplitude, and sensory nerve conduction velocity were assessed before and after the six week therapy period. [Results] A significant intergroup difference was observed for posttreatment velocity gains, but no significant intergroup difference was observed for amplitude or latency. [Conclusion] repetitive transcranial magnetic stimulation may be improve sensory recovery of the lower extremities in subacute-stage spinal cord injury patients.

Peripheral Nerve Injuries and Transplantation of Olfactory Ensheathing Cells for Axonal Regeneration and Remyelination: Fact or Fiction?

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Christine Radtke

2012-10-01

Full Text Available Successful nerve regeneration after nerve trauma is not only important for the restoration of motor and sensory functions, but also to reduce the potential for abnormal sensory impulse generation that can occur following neuroma formation. Satisfying functional results after severe lesions are difficult to achieve and the development of interventional methods to achieve optimal functional recovery after peripheral nerve injury is of increasing clinical interest. Olfactory ensheathing cells (OECs have been used to improve axonal regeneration and functional outcome in a number of studies in spinal cord injury models. The rationale is that the OECs may provide trophic support and a permissive environment for axonal regeneration. The experimental transplantation of OECs to support and enhance peripheral nerve regeneration is much more limited. This chapter reviews studies using OECs as an experimental cell therapy to improve peripheral nerve regeneration.

Interplay between mast cells, enterochromaffin cells, and sensory signaling in the aging human bowel.

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Yu, Y; Daly, D M; Adam, I J; Kitsanta, P; Hill, C J; Wild, J; Shorthouse, A; Grundy, D; Jiang, W

2016-10-01

Advanced age is associated with a reduction in clinical visceral pain perception. However, the underlying mechanisms remain largely unknown. Previous studies have suggested that an abnormal interplay between mast cells, enterochromaffin (EC) cells, and afferent nerves contribute to nociception in gastrointestinal disorders. The aim of this study was to investigate how aging affects afferent sensitivity and neuro-immune association in the human bowel. Mechanical and chemical sensitivity of human bowel afferents were examined by ex vivo afferent nerve recordings. Age-related changes in the density of mast cells, EC cells, sensory nerve terminals, and mast cell-nerve micro-anatomical association were investigated by histological and immune staining. Human afferents could be broadly classified into subpopulations displaying mechanical and chemical sensitivity, adaptation, chemo-sensitization, and recruitment. Interestingly human bowel afferent nerve sensitivity was attenuated with age. The density of substance P-immunoreactive (SP-IR) nerve varicosities was also reduced with age. In contrast, the density of ileal and colonic mucosal mast cells was increased with age, as was ileal EC cell number. An increased proportion of mast cells was found in close apposition to SP-IR nerves. Afferent sensitivity in human bowel was reduced with advancing age. Augmentation of mast cells and EC cell numbers and the mast cell-nerve association suggest a compensatory mechanism for sensory neurodegeneration. © 2016 The Authors. Neurogastroenterology & Motility Published by John Wiley & Sons Ltd.

Impaired peripheral nerve regeneration in type-2 diabetic mouse model.

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Pham, Vuong M; Tu, Nguyen Huu; Katano, Tayo; Matsumura, Shinji; Saito, Akira; Yamada, Akihiro; Furue, Hidemasa; Ito, Seiji

2018-01-01

Peripheral neuropathy is one of the most common and serious complications of type-2 diabetes. Diabetic neuropathy is characterized by a distal symmetrical sensorimotor polyneuropathy, and its incidence increases in patients 40 years of age or older. In spite of extensive research over decades, there are few effective treatments for diabetic neuropathy besides glucose control and improved lifestyle. The earliest changes in diabetic neuropathy occur in sensory nerve fibers, with initial degeneration and regeneration resulting in pain. To seek its effective treatment, here we prepared a type-2 diabetic mouse model by giving mice 2 injections of streptozotocin and nicotinamide and examining the ability for nerve regeneration by using a sciatic nerve transection-regeneration model previously established by us. Seventeen weeks after the last injection, the mice exhibited symptoms of type-2 diabetes, that is, impaired glucose tolerance, decreased insulin level, mechanical hyperalgesia, and impaired sensory nerve fibers in the plantar skin. These mice showed delayed functional recovery and nerve regeneration by 2 weeks compared with young healthy mice and by 1 week compared with age-matched non-diabetic mice after axotomy. Furthermore, type-2 diabetic mice displayed increased expression of PTEN in their DRG neurons. Administration of a PTEN inhibitor at the cutting site of the nerve for 4 weeks promoted the axonal transport and functional recovery remarkably. This study demonstrates that peripheral nerve regeneration was impaired in type-2 diabetic model and that its combination with sciatic nerve transection is suitable for the study of the pathogenesis and treatment of early diabetic neuropathy. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Postherniotomy dysejaculation: successful treatment with mesh removal and nerve transection

DEFF Research Database (Denmark)

Aasvang, Eske Kvanner; Kehlet, H.

2008-01-01

Dysejaculation following groin hernia repair can occur in about 1-2% of patients, resulting in impairment of sexual function. We report a case of chronic postherniotomy dysejaculation treated with transection of the ilioinguinal and iliohypogastric nerves and decompression of vas deferens...... that was embedded and twisted in shrunken mesh and scar tissue. At three months follow-up, there was reduced overall pain and no dysejaculation, and quantitative sensory testing showed reversal of sensory abnormalities, except for sensory loss, compared with preoperative values Udgivelsesdato: 2008/12...

[Two cases of hereditary motor and sensory neuropathy with proximal dominant involvement (HMSN-P)].

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Mori, Chiaki; Saito, Tomoko; Saito, Toshio; Fujimura, Harutoshi; Sakoda, Saburo

2015-01-01

We, herein, report two independent cases with hereditary motor and sensory neuropathy with proximal dominant involvement (HMSN-P) inherited in an autosomal dominant fashion. Their common clinical features are slowly progressive proximal dominant muscular atrophy, fasciculations and mild to moderate distal sensory disturbance with areflexia. Nerve conduction study revealed an absence of sensory nerve action potentials, in contrast to almost normal compound muscle action potentials. Gene analysis in both patients elucidated heterozygous mutation (c.854C>T, p.Pro285Leu) in the TFG, which is an identical mutation, already described by Ishiura et al. Okinawa and Shiga are two foci of HMSN-P in Japan. Eventually, one patient is from Okinawa and the other is from a mountain village in Shiga prefecture. When we see a patient who has symptoms suggestive of motor neuron disease with sensory neuropathy, HMSN-P should be considered as a differential diagnosis despite the patient's actual resident place.

Sensory mediation of memory blocking stressors in the pond snail Lymnaea stagnalis.

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Dalesman, Sarah; Karnik, Vikram; Lukowiak, Ken

2011-08-01

The great pond snail, Lymnaea stagnalis, is commonly used as a model species to study how stress affects the ability to form long-term memory (LTM); however, we still have little information about how the snail senses stressful stimuli. The osphradium is an external sensory organ that demonstrates electrophysiological responses to a variety of external chemical stimuli. We examined the role, if any, played by the osphradium in sensing two environmental stressors, crowding and low environmental calcium, both known to block LTM in intact animals. We severed the osphradial nerve, blocking external sensory input from this organ to the central nervous system, and then exposed the snails to low environmental calcium or crowding stress to assess whether these stressors continued to block LTM formation. When exposed to low environmental calcium, snails with their osphradial nerve severed responded as if they were maintained in our standard calcium environment. That is, they did not respond to low calcium as a stressor blocking LTM; therefore, the osphradium plays a crucial role in mediating how snails respond to this stressor. However, following crowding, LTM formation was blocked in both control groups and snails that had the osphradial nerve severed, indicating that sensory information from the osphradium is not required to sense crowded conditions. Together these data show that two stressors that result in the same behavioural phenotype, blocking LTM formation, do so via two distinct sensory pathways.

Histone Deacetylase Inhibition via RGFP966 Releases the Brakes on Sensory Cortical Plasticity and the Specificity of Memory Formation.

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Bieszczad, Kasia M; Bechay, Kiro; Rusche, James R; Jacques, Vincent; Kudugunti, Shashi; Miao, Wenyan; Weinberger, Norman M; McGaugh, James L; Wood, Marcelo A

2015-09-23

Research over the past decade indicates a novel role for epigenetic mechanisms in memory formation. Of particular interest is chromatin modification by histone deacetylases (HDACs), which, in general, negatively regulate transcription. HDAC deletion or inhibition facilitates transcription during memory consolidation and enhances long-lasting forms of synaptic plasticity and long-term memory. A key open question remains: How does blocking HDAC activity lead to memory enhancements? To address this question, we tested whether a normal function of HDACs is to gate information processing during memory formation. We used a class I HDAC inhibitor, RGFP966 (C21H19FN4O), to test the role of HDAC inhibition for information processing in an auditory memory model of learning-induced cortical plasticity. HDAC inhibition may act beyond memory enhancement per se to instead regulate information in ways that lead to encoding more vivid sensory details into memory. Indeed, we found that RGFP966 controls memory induction for acoustic details of sound-to-reward learning. Rats treated with RGFP966 while learning to associate sound with reward had stronger memory and additional information encoded into memory for highly specific features of sounds associated with reward. Moreover, behavioral effects occurred with unusually specific plasticity in primary auditory cortex (A1). Class I HDAC inhibition appears to engage A1 plasticity that enables additional acoustic features to become encoded in memory. Thus, epigenetic mechanisms act to regulate sensory cortical plasticity, which offers an information processing mechanism for gating what and how much is encoded to produce exceptionally persistent and vivid memories. Significance statement: Here we provide evidence of an epigenetic mechanism for information processing. The study reveals that a class I HDAC inhibitor (Malvaez et al., 2013; Rumbaugh et al., 2015; RGFP966, chemical formula C21H19FN4O) alters the formation of auditory memory by

Histone Deacetylase Inhibition via RGFP966 Releases the Brakes on Sensory Cortical Plasticity and the Specificity of Memory Formation

Science.gov (United States)

Bechay, Kiro; Rusche, James R.; Jacques, Vincent; Kudugunti, Shashi; Miao, Wenyan; Weinberger, Norman M.; McGaugh, James L.

2015-01-01

Research over the past decade indicates a novel role for epigenetic mechanisms in memory formation. Of particular interest is chromatin modification by histone deacetylases (HDACs), which, in general, negatively regulate transcription. HDAC deletion or inhibition facilitates transcription during memory consolidation and enhances long-lasting forms of synaptic plasticity and long-term memory. A key open question remains: How does blocking HDAC activity lead to memory enhancements? To address this question, we tested whether a normal function of HDACs is to gate information processing during memory formation. We used a class I HDAC inhibitor, RGFP966 (C21H19FN4O), to test the role of HDAC inhibition for information processing in an auditory memory model of learning-induced cortical plasticity. HDAC inhibition may act beyond memory enhancement per se to instead regulate information in ways that lead to encoding more vivid sensory details into memory. Indeed, we found that RGFP966 controls memory induction for acoustic details of sound-to-reward learning. Rats treated with RGFP966 while learning to associate sound with reward had stronger memory and additional information encoded into memory for highly specific features of sounds associated with reward. Moreover, behavioral effects occurred with unusually specific plasticity in primary auditory cortex (A1). Class I HDAC inhibition appears to engage A1 plasticity that enables additional acoustic features to become encoded in memory. Thus, epigenetic mechanisms act to regulate sensory cortical plasticity, which offers an information processing mechanism for gating what and how much is encoded to produce exceptionally persistent and vivid memories. SIGNIFICANCE STATEMENT Here we provide evidence of an epigenetic mechanism for information processing. The study reveals that a class I HDAC inhibitor (Malvaez et al., 2013; Rumbaugh et al., 2015; RGFP966, chemical formula C21H19FN4O) alters the formation of auditory memory by

Functional role of peripheral opioid receptors in the regulation of cardiac spinal afferent nerve activity during myocardial ischemia

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Longhurst, John C.

2013-01-01

Thinly myelinated Aδ-fiber and unmyelinated C-fiber cardiac sympathetic (spinal) sensory nerve fibers are activated during myocardial ischemia to transmit the sensation of angina pectoris. Although recent observations showed that myocardial ischemia increases the concentrations of opioid peptides and that the stimulation of peripheral opioid receptors inhibits chemically induced visceral and somatic nociception, the role of opioids in cardiac spinal afferent signaling during myocardial ischemia has not been studied. The present study tested the hypothesis that peripheral opioid receptors modulate cardiac spinal afferent nerve activity during myocardial ischemia by suppressing the responses of cardiac afferent nerve to ischemic mediators like bradykinin and extracellular ATP. The nerve activity of single unit cardiac afferents was recorded from the left sympathetic chain (T2–T5) in anesthetized cats. Forty-three ischemically sensitive afferent nerves (conduction velocity: 0.32–3.90 m/s) with receptive fields in the left and right ventricles were identified. The responses of these afferent nerves to repeat ischemia or ischemic mediators were further studied in the following protocols. First, epicardial administration of naloxone (8 μmol), a nonselective opioid receptor antagonist, enhanced the responses of eight cardiac afferent nerves to recurrent myocardial ischemia by 62%, whereas epicardial application of vehicle (PBS) did not alter the responses of seven other cardiac afferent nerves to ischemia. Second, naloxone applied to the epicardial surface facilitated the responses of seven cardiac afferent nerves to epicardial ATP by 76%. Third, administration of naloxone enhanced the responses of seven other afferent nerves to bradykinin by 85%. In contrast, in the absence of naloxone, cardiac afferent nerves consistently responded to repeated application of ATP (n = 7) or bradykinin (n = 7). These data suggest that peripheral opioid peptides suppress the

Acute corneal epithelial debridement unmasks the corneal stromal nerve responses to ocular stimulation in rats: implications for abnormal sensations of the eye.

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Hirata, Harumitsu; Mizerska, Kamila; Dallacasagrande, Valentina; Guaiquil, Victor H; Rosenblatt, Mark I

2017-05-01

It is widely accepted that the mechanisms for transducing sensory information reside in the nerve terminals. Occasionally, however, studies have appeared demonstrating that similar mechanisms may exist in the axon to which these terminals are connected. We examined this issue in the cornea, where nerve terminals in the epithelial cell layers are easily accessible for debridement, leaving the underlying stromal (axonal) nerves undisturbed. In isoflurane-anesthetized rats, we recorded extracellularly from single trigeminal ganglion neurons innervating the cornea that are excited by ocular dryness and cooling: low-threshold (2°C) cold-sensitive plus dry-sensitive neurons playing possible roles in tearing and ocular pain. We found that the responses in both types of neurons to dryness, wetness, and menthol stimuli were effectively abolished by the debridement, indicating that their transduction mechanisms lie in the nerve terminals. However, some responses to the cold, heat, and hyperosmolar stimuli in low-threshold cold-sensitive plus dry-sensitive neurons still remained. Surprisingly, the responses to heat in approximately half of the neurons were augmented after the debridement. We were also able to evoke these residual responses and follow the trajectory of the stromal nerves, which we subsequently confirmed histologically. The residual responses always disappeared when the stromal nerves were cut at the limbus, suggesting that the additional transduction mechanisms for these sensory modalities originated most likely in stromal nerves. The functional significance of these residual and enhanced responses from stromal nerves may be related to the abnormal sensations observed in ocular disease. NEW & NOTEWORTHY In addition to the traditional view that the sensory transduction mechanisms exist in the nerve terminals, we report here that the proximal axons (stromal nerves in the cornea from which these nerve terminals originate) may also be capable of transducing

Evaluation of sensory function and recovery after replantation of fingertips at Zone I in children.

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Zhu, Zhao-Wei; Zou, Xiao-Yan; Huang, Yong-Jun; Liu, Jiang-Hui; Huang, Xi-Jun; He, Bo; Wang, Zeng-Tao

2017-11-01

Sensory function is the most significant criterion when evaluating the prognosis of replanted fingers. Current clinical research has focused on surgical techniques and indications for finger replantation; however, few studies have focused on recovery of finger sensory function after replantation. This study retrospectively assessed data of eight patients who had undergone nine Zone I replantations of the fingertips in the First Affiliated Hospital of Sun Yat-sen University of China from July 2014 to January 2016. Variations in the extent of damage, with the residual vessels or nerves in some fingers being too short or even missing, prevented tension-free suture repair in some patients. Thus, repair of four of the nine fingertips included arteriovenous anastomosis, the remaining five undergoing arterial anastomosis during replantation of the amputated fingers. Three patients underwent nerve repair, whereas the remaining six cases did not. Fingertip replantations were successful in all eight patients. Compared with the patients without vascular anastomosis, no obvious atrophy was visible in the fingertips of patients who did undergo vascular anastomosis during replantation and their sensory function did recover. Fingertip replantation provides good sensory function and cosmetic outcomes when good artery and vein anastomoses have been created, even when digital nerves have not been repaired.

Evaluation of sensory function and recovery after replantation of fingertips at Zone I in children

Directory of Open Access Journals (Sweden)

Zhao-wei Zhu

2017-01-01

Full Text Available Sensory function is the most significant criterion when evaluating the prognosis of replanted fingers. Current clinical research has focused on surgical techniques and indications for finger replantation; however, few studies have focused on recovery of finger sensory function after replantation. This study retrospectively assessed data of eight patients who had undergone nine Zone I replantations of the fingertips in the First Affiliated Hospital of Sun Yat-sen University of China from July 2014 to January 2016. Variations in the extent of damage, with the residual vessels or nerves in some fingers being too short or even missing, prevented tension-free suture repair in some patients. Thus, repair of four of the nine fingertips included arteriovenous anastomosis, the remaining five undergoing arterial anastomosis during replantation of the amputated fingers. Three patients underwent nerve repair, whereas the remaining six cases did not. Fingertip replantations were successful in all eight patients. Compared with the patients without vascular anastomosis, no obvious atrophy was visible in the fingertips of patients who did undergo vascular anastomosis during replantation and their sensory function did recover. Fingertip replantation provides good sensory function and cosmetic outcomes when good artery and vein anastomoses have been created, even when digital nerves have not been repaired.

[Clinical report of hereditary motor and sensory neuropathy with proximal dominance in Shiga prefecture].

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Takahashi, Mitsuo; Mitsui, Yoshiyuki; Yorifuji, Shiro; Nakamura, Yuusaku; Tsukamoto, Yoshihumi; Nishimoto, Kazuhiro

2007-09-01

We followed eight hereditary motor and sensory neuropathy patients with proximal dominance (HMSN-P) in Shiga prefecture from 1984 to 2007. There were 4 men and 4 women from two families showing autosomal and dominant prepotency. These families were related by marriage. The average onset of disease was at 53.4 +/- 8.9 (40-68) years-old. Initial symptoms were difficulty of standing up, difficulty elevating their arms, limping, or numbness. The main feature was neurogenic muscular atrophy with proximal dominance. All deep tendon reflexes were decreased or nonexistent. Paresthesia in the hands and feet and/or decreased vibratory sense in the legs were found in six patients. High CK blood levels were recognized in three patients. EMG in four patients revealed neurogenic pattern. Nerve conduction study was conducted in two patients. MCV of the median nerve and of the tibial posterior nerve, also SCV of the median nerve and of the sural nerve were within normal range in all nerves. Amplitudes of sensory action potential or of M wave were decreased or nonexistent in five of eight nerves, and distal latency of M waves was delayed in three of four nerves. These data suggests dysfunction of distal parts of the peripheral nerve fibers and axonal degeneration of the nerve trunk. Seven patients have died, and their average death age was 69.1 +/- 8.2 (52-77) years-old. Their average affected period was 16.6 (4-30) years. Their clinical history resembles Okinawa-type HMSN-P, but without the painful muscle cramps which are distinctive Okinawa-type signs.

Intraglomerular inhibition maintains mitral cell response contrast across input frequencies.

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Shao, Zuoyi; Puche, Adam C; Shipley, Michael T

2013-11-01

Odor signals are transmitted to the olfactory bulb by olfactory nerve (ON) synapses onto mitral/tufted cells (MTCs) and external tufted cells (ETCs); ETCs provide additional feed-forward excitation to MTCs. Both are strongly regulated by intraglomerular inhibition that can last up to 1 s and, when blocked, dramatically increases ON-evoked MC spiking. Intraglomerular inhibition thus limits the magnitude and duration of MC spike responses to sensory input. In vivo, sensory input is repetitive, dictated by sniffing rates from 1 to 8 Hz, potentially summing intraglomerular inhibition. To investigate this, we recorded MTC responses to 1- to 8-Hz ON stimulation in slices. Inhibitory postsynaptic current area (charge) following each ON stimulation was unchanged from 1 to 5 Hz and modestly paired-pulse attenuated at 8 Hz, suggesting there is no summation and only limited decrement at the highest input frequencies. Next, we investigated frequency independence of intraglomerular inhibition on MC spiking. MCs respond to single ON shocks with an initial spike burst followed by reduced spiking decaying to baseline. Upon repetitive ON stimulation peak spiking is identical across input frequencies but the ratio of peak-to-minimum rate before the stimulus (max-min) diminishes from 30:1 at 1 Hz to 15:1 at 8 Hz. When intraglomerular inhibition is selectively blocked, peak spike rate is unchanged but trough spiking increases markedly decreasing max-min firing ratios from 30:1 at 1 Hz to 2:1 at 8 Hz. Together, these results suggest intraglomerular inhibition is relatively frequency independent and can "sharpen" MC responses to input across the range of frequencies. This suggests that glomerular circuits can maintain "contrast" in MC encoding during sniff-sampled inputs.

[Herpes zoster of the trigeminal nerve: a case report and review of the literature].

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Carbone, V; Leonardi, A; Pavese, M; Raviola, E; Giordano, M

2004-01-01

Herpes zoster (shingles) is caused when the varicella zoster virus that has remained latent since an earlier varicella infection (chicken-pox) is reactivated. Herpes Zoster is a less common and endemic disease than varicella: factors causing reactivation are still not well known, but it occurs in older and/or immunocompromised individuals. Following reactivation, centrifugal migration of herpes zoster virus (HZV) occurs along sensory nerves to produce a characteristic painful cutaneous or mucocutaneous vesicular eruption that is generally limited to the single affected dermatome. Herpes zoster may affect any sensory ganglia and its cutaneous nerve: the most common sites affected are thoracic dermatomes (56%), followed by cranial nerves (13%) and lumbar (13%), cervical (11%) and sacral nerves (4%). Among cranial nerves, the trigeminal and facial nerves are the most affected due to reactivation of HZV latent in gasserian and geniculated ganglia. The 1st division of the trigeminal nerve is commonly affected, whereas the 2nd and the 3rd are rarely involved. During the prodromal stage, the only presenting symptom may be odontalgia, which may prove to be a diagnostic challenge for the dentist, since many diseases can cause orofacial pain, and the diagnosis must be established before final treatment. A literature review of herpes zoster of the trigeminal nerve is presented and the clinical presentation, differential diagnosis and treatment modalities are underlined. A case report is presented.

Terminal changes in hereditary sensory and autonomic neuropathy: a long-term follow-up of a sporadic case.

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Lee, Sang-Soo; Lee, Sung-Hyun; Han, Seol-Heui

2003-07-01

We describe terminal changes in a long-term follow-up of a 51-year-old man with sporadic hereditary sensory and autonomic neuropathy (HSAN). From the age of 15 years onwards, he suffered from multiple painless ulcers of his feet and fingers, necessitating amputation. Neurological studies revealed almost complete sensory loss affecting all modalities in the upper and lower limbs, minimal involvement of motor fibers, and areflexia. A neurophysiological abnormality involved an absence of sensory action potentials with relatively normal motor nerve conduction velocities. Biopsy of the sural nerve showed almost total loss of myelinated fibers with a mild decrease in unmyelinated fibers. Despite the late onset of the disease, the progressive course, and the lancinating pain, the terminal features of this patient, which involved a selective loss of myelinated fibers and widespread sensory loss, seem to be symptomatic of HSAN II, the progressive form of autosomal recessive sensory neuropathy, and emphasize the clinical heterogeneity of HSAN.

Nerves Regulate Cardiomyocyte Proliferation and Heart Regeneration.

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Mahmoud, Ahmed I; O'Meara, Caitlin C; Gemberling, Matthew; Zhao, Long; Bryant, Donald M; Zheng, Ruimao; Gannon, Joseph B; Cai, Lei; Choi, Wen-Yee; Egnaczyk, Gregory F; Burns, Caroline E; Burns, C Geoffrey; MacRae, Calum A; Poss, Kenneth D; Lee, Richard T

2015-08-24

Some organisms, such as adult zebrafish and newborn mice, have the capacity to regenerate heart tissue following injury. Unraveling the mechanisms of heart regeneration is fundamental to understanding why regeneration fails in adult humans. Numerous studies have revealed that nerves are crucial for organ regeneration, thus we aimed to determine whether nerves guide heart regeneration. Here, we show using transgenic zebrafish that inhibition of cardiac innervation leads to reduction of myocyte proliferation following injury. Specifically, pharmacological inhibition of cholinergic nerve function reduces cardiomyocyte proliferation in the injured hearts of both zebrafish and neonatal mice. Direct mechanical denervation impairs heart regeneration in neonatal mice, which was rescued by the administration of neuregulin 1 (NRG1) and nerve growth factor (NGF) recombinant proteins. Transcriptional analysis of mechanically denervated hearts revealed a blunted inflammatory and immune response following injury. These findings demonstrate that nerve function is required for both zebrafish and mouse heart regeneration. Copyright © 2015 Elsevier Inc. All rights reserved.

Constriction of the buccal branch of the facial nerve produces unilateral craniofacial allodynia.

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Lewis, Susannah S; Grace, Peter M; Hutchinson, Mark R; Maier, Steven F; Watkins, Linda R

2017-08-01

Despite pain being a sensory experience, studies of spinal cord ventral root damage have demonstrated that motor neuron injury can induce neuropathic pain. Whether injury of cranial motor nerves can also produce nociceptive hypersensitivity has not been addressed. Herein, we demonstrate that chronic constriction injury (CCI) of the buccal branch of the facial nerve results in long-lasting, unilateral allodynia in the rat. An anterograde and retrograde tracer (3000MW tetramethylrhodamine-conjugated dextran) was not transported to the trigeminal ganglion when applied to the injury site, but was transported to the facial nucleus, indicating that this nerve branch is not composed of trigeminal sensory neurons. Finally, intracisterna magna injection of interleukin-1 (IL-1) receptor antagonist reversed allodynia, implicating the pro-inflammatory cytokine IL-1 in the maintenance of neuropathic pain induced by facial nerve CCI. These data extend the prior evidence that selective injury to motor axons can enhance pain to supraspinal circuits by demonstrating that injury of a facial nerve with predominantly motor axons is sufficient for neuropathic pain, and that the resultant pain has a neuroimmune component. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of superficial radial nerve stimulation on the activity of nigro-striatal dopaminergic neurons in the cat: role of cutaneous sensory input

International Nuclear Information System (INIS)

Nieoullon, A.; Dusticier, N.

1982-01-01

The release of 3 H-dopamine (DA) continuously synthesized from 3 H-thyrosine was measured in the caudate nucleus (CN) and in the substantia nigra (SN) in both sides of the brain during electrical stimulation of the superficial radial nerve in cats lightly anaesthetized with halothane. Use of appropriate electrophysiologically controlled stimulation led to selective activation of low threshold afferent fibers whereas high stimulation activated all cutaneous afferents. Results showed that low threshold fiber activation induced a decreased dopaminergic activity in CN contralateral to nerve stimulation and a concomitant increase in dopaminergic activity on the ipsilateral side. Stimulation of group I and threshold stimulation of group II afferent fibers induced changes in the release of 3 H-DA mainly on the contralateral CN and SN and in the ipsilateral CN. High stimulation was followed by a general increase of the neurotransmitter release in the four structures. This shows that the nigro-striatal dopaminergic neurons are mainly-if not exclusively-controlled by cutaneous sensory inputs. This control, non-specific when high threshold cutaneous fibers are also activated. Such activations could contribute to restablish sufficient release of DA when the dopaminergic function is impaired as in Parkinson's disease. (Author)

Effect of superficial radial nerve stimulation on the activity of nigro-striatal dopaminergic neurons in the cat: role of cutaneous sensory input

Energy Technology Data Exchange (ETDEWEB)

Nieoullon, A; Dusticier, N [Centre National de la Recherche Scientifique, 13 - Marseille (France). Inst. de Neurophysiologie et Psychophysiologie

1982-01-01

The release of /sup 3/H-dopamine (DA) continuously synthesized from /sup 3/H-thyrosine was measured in the caudate nucleus (CN) and in the substantia nigra (SN) in both sides of the brain during electrical stimulation of the superficial radial nerve in cats lightly anaesthetized with halothane. Use of appropriate electrophysiologically controlled stimulation led to selective activation of low threshold afferent fibers whereas high stimulation activated all cutaneous afferents. Results showed that low threshold fiber activation induced a decreased dopaminergic activity in CN contralateral to nerve stimulation and a concomitant increase in dopaminergic activity on the ipsilateral side. Stimulation of group I and threshold stimulation of group II afferent fibers induced changes in the release of /sup 3/H-DA mainly on the contralateral CN and SN and in the ipsilateral CN. High stimulation was followed by a general increase of the neurotransmitter release in the four structures. This shows that the nigro-striatal dopaminergic neurons are mainly-if not exclusively-controlled by cutaneous sensory inputs. This control, non-specific when high threshold cutaneous fibers are also activated. Such activations could contribute to reestablish sufficient release of DA when the dopaminergic function is impaired as in Parkinson's disease.

Fine structure of subepithelial "free" and corpuscular trigeminal nerve endings in anterior hard palate of the rat.

Science.gov (United States)

Byers, M R; Yeh, Y

1984-01-01

Axonally transported protein labeled many trigeminal nerve endings in subepithelial regions of the anterior hard palate of the rat. Sensory endings were most numerous in the lamina propria near the tips of the palatal rugae where large connective tissue and epithelial papillae interdigitated. Two kinds of sensory ending were found there: "free" endings, and a variety of corpuscular endings. The "free" sensory endings consisted of bundles of unmyelinated axons separated from the connective tissue by relatively unspecialized Schwann cells covering part or all of their surface and a completely continuous basal lamina; they were commonly found running parallel to the epithelium or near corpuscular endings. The corpuscular sensory endings all had a specialized nerve form, specialized Schwann cells, and axonal fingers projecting into the corpuscular basal lamina or connective tissue. There were at least four distinct types of corpuscular ending: Ruffini-like endings were found among dense collagen bundles, and they had a flattened nerve ending with a flattened Schwann lamella on either side. Meissner endings had an ordered stack of flattened nerve terminals with flattened Schwann cells and much basal lamina within and around the corpuscle. Simple corpuscles were single nerve endings surrounded by several layers of concentric lamellar Schwann processes. Glomerular endings were found in lamina propria papillae or encircling epithelial papillae; they were a tangle of varied neural forms each of which had apposed flattened Schwann cells, and a layer of basal lamina of varied thickness. Fibroblasts often formed incomplete partitions around Meissner and simple corpuscles. The axoplasm of all kinds of subepithelial sensory endings contained numerous mitochondria and vesicles, as well as occasional multivesicular bodies and lysosomes; the axoplasm of all endings was pale with few microtubules and neurofilaments. The specialized lamellar Schwann cells had much pinocytotic

Engineering a multimodal nerve conduit for repair of injured peripheral nerve

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Quigley, A. F.; Bulluss, K. J.; Kyratzis, I. L. B.; Gilmore, K.; Mysore, T.; Schirmer, K. S. U.; Kennedy, E. L.; O'Shea, M.; Truong, Y. B.; Edwards, S. L.; Peeters, G.; Herwig, P.; Razal, J. M.; Campbell, T. E.; Lowes, K. N.; Higgins, M. J.; Moulton, S. E.; Murphy, M. A.; Cook, M. J.; Clark, G. M.; Wallace, G. G.; Kapsa, R. M. I.

2013-02-01

Injury to nerve tissue in the peripheral nervous system (PNS) results in long-term impairment of limb function, dysaesthesia and pain, often with associated psychological effects. Whilst minor injuries can be left to regenerate without intervention and short gaps up to 2 cm can be sutured, larger or more severe injuries commonly require autogenous nerve grafts harvested from elsewhere in the body (usually sensory nerves). Functional recovery is often suboptimal and associated with loss of sensation from the tissue innervated by the harvested nerve. The challenges that persist with nerve repair have resulted in development of nerve guides or conduits from non-neural biological tissues and various polymers to improve the prognosis for the repair of damaged nerves in the PNS. This study describes the design and fabrication of a multimodal controlled pore size nerve regeneration conduit using polylactic acid (PLA) and (PLA):poly(lactic-co-glycolic) acid (PLGA) fibers within a neurotrophin-enriched alginate hydrogel. The nerve repair conduit design consists of two types of PLGA fibers selected specifically for promotion of axonal outgrowth and Schwann cell growth (75:25 for axons; 85:15 for Schwann cells). These aligned fibers are contained within the lumen of a knitted PLA sheath coated with electrospun PLA nanofibers to control pore size. The PLGA guidance fibers within the nerve repair conduit lumen are supported within an alginate hydrogel impregnated with neurotrophic factors (NT-3 or BDNF with LIF, SMDF and MGF-1) to provide neuroprotection, stimulation of axonal growth and Schwann cell migration. The conduit was used to promote repair of transected sciatic nerve in rats over a period of 4 weeks. Over this period, it was observed that over-grooming and self-mutilation (autotomy) of the limb implanted with the conduit was significantly reduced in rats implanted with the full-configuration conduit compared to rats implanted with conduits containing only an alginate

Expression patterns and role of PTEN in rat peripheral nerve development and injury.

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Chen, Hui; Xiang, Jianping; Wu, Junxia; He, Bo; Lin, Tao; Zhu, Qingtang; Liu, Xiaolin; Zheng, Canbin

2018-05-29

Studies have suggested that phosphatase and tensin homolog (PTEN) plays an important role in neuroprotection and neuronal regeneration. To better understand the potential role of PTEN with respect to peripheral nerve development and injury, we investigated the expression pattern of PTEN at different stages of rat peripheral nerve development and injury and subsequently assessed the effect of pharmacological inhibition of PTEN using bpV(pic) on axonal regeneration in a rat sciatic nerve crush injury model. During the early stages of development, PTEN exhibits low expression in neuronal cell bodies and axons. From embryonic day (E) 18.5 and postnatal day (P)5 to adult, PTEN protein becomes more detectable, with high expression in the dorsal root ganglia (DRG) and axons. PTEN expression is inhibited in peripheral nerves, preceding myelination during neuronal development and remyelination after acute nerve injury. Low PTEN expression after nerve injury promotes Akt/mammalian target of rapamycin (mTOR) signaling pathway activity. In vivo pharmacological inhibition of PTEN using bpV(pic) promoted axonal regrowth, increased the number of myelinated nerve fibers, improved locomotive recovery and enhanced the amplitude response and nerve conduction velocity following stimulation in a rat sciatic nerve crush injury model. Thus, we suggest that PTEN may play potential roles in peripheral nerve development and regeneration and that inhibition of PTEN expression is beneficial for nerve regeneration and functional recovery after peripheral nerve injury. Copyright © 2018 Elsevier B.V. All rights reserved.

A fine structural localization of the non-specific cholinesterase activity in glomerular nerve formations (endings).

Science.gov (United States)

Dubový, P

1990-01-01

Snout glabrous skin (rhinarium) of the cat is innervated not only by typical simple lamellar corpuscles but also glomerular formations. In contrast to simple lamellar corpuscles, glomerular nerve formations are located away the dermal papillae. In cross sections, glomerular nerve formation consists of several axonal profiles enveloped by 1-2 cytoplasmic lamellae of Schwann cells. The space among them is filled by collagenous microfibrils and the basal lamina-like material. Capsule was composed from fibroblast-like cells without definite basal lamina. An electron-dense reaction product due to non-specific cholinesterase activity was associated with Schwann cells and their processes surrounding unmyelinated terminal portion of the sensory axons. Abundant reaction product was bound to the collagenous microfibrils and was deposited in extracellular matrix between Schwann cell processes. These results are further evidence for the presence of the non-specific cholinesterase molecules as integral component of the extracellular matrix in sensory corpuscles. On the basis of histochemical study two possible explanation are considered for functional involving of this enzyme in sensory nerve formations.

Late sensory function after intraoperative capsaicin wound instillation

DEFF Research Database (Denmark)

Aasvang, E K; Hansen, J B; Kehlet, H

2010-01-01

is partly re-established after skin injection of capsaicin. However, no study has evaluated the long-term effects of wound instillation of purified capsaicin on sensory functions. METHODS: Patients included in a double-blind placebo-controlled randomized study of the analgesic effect of capsaicin after....... placebo group at the 1-week follow-up (Pfunction on the operated side between groups at the pre-operative, 1-week or 2 1/2 year post-operative follow-up (P>0.05). The sensory function......BACKGROUND: Intense capsaicin-induced C-fiber stimulation results in reversible lysis of the nerve soma, thereby making capsaicin wound instillation of potential interest for the treatment of post-operative pain. Clinical histological and short-term sensory studies suggest that the C-fiber function...

Peptidomics and Secretomics of the Mammalian Peripheral Sensory-Motor System

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Tillmaand, Emily G.; Yang, Ning; Kindt, Callie A. C.; Romanova, Elena V.; Rubakhin, Stanislav S.; Sweedler, Jonathan V.

2015-12-01

The dorsal root ganglion (DRG) and its anatomically and functionally associated spinal nerve and ventral and dorsal roots are important components of the peripheral sensory-motor system in mammals. The cells within these structures use a number of peptides as intercellular signaling molecules. We performed a variety of mass spectrometry (MS)-based characterizations of peptides contained within and secreted from these structures, and from isolated and cultured DRG cells. Liquid chromatography-Fourier transform MS was utilized in DRG and nerve peptidome analysis. In total, 2724 peptides from 296 proteins were identified in tissue extracts. Neuropeptides are among those detected, including calcitonin gene-related peptide I, little SAAS, and known hemoglobin-derived peptides. Solid phase extraction combined with direct matrix-assisted laser desorption/ionization time-of-flight MS was employed to investigate the secretome of these structures. A number of peptides were detected in the releasate from semi-intact preparations of DRGs and associated nerves, including neurofilament- and myelin basic protein-related peptides. A smaller set of analytes was observed in releasates from cultured DRG neurons. The peptide signals observed in the releasates have been mass-matched to those characterized and identified in homogenates of entire DRGs and associated nerves. This data aids our understanding of the chemical composition of the mammalian peripheral sensory-motor system, which is involved in key physiological functions such as nociception, thermoreception, itch sensation, and proprioception.

Injectable systems and implantable conduits for peripheral nerve repair

International Nuclear Information System (INIS)

Lin, Yen-Chih; Marra, Kacey G

2012-01-01

Acute sensory problems following peripheral nerve injury include pain and loss of sensation. Approximately 360 000 people in the United States suffer from upper extremity paralytic syndromes every year. Restoration of sufficient functional recovery after long-gap peripheral nerve damage remains a clinical challenge. Potential nerve repair therapies have increased in the past decade as the field of tissue engineering expands. The following review describes the use of biomaterials in nerve tissue engineering. Namely, the use of both synthetic and natural biomaterials, including non-degradable and degradable nerve grafts, is addressed. The enhancement of axonal regeneration can be achieved by further modification of the nerve guides. These approaches include injectable hydrogel fillers, controlled drug delivery systems, and cell incorporation. Hydrogels are a class of liquid–gel biomaterials with high water content. Injectable and gelling hydrogels can serve as growth factor delivery vehicles and cell carriers for tissue engineering applications. While natural hydrogels and polymers are suitable for short gap nerve repair, the use of polymers for relatively long gaps remains a clinical challenge. (paper)

Annotation of nerve cord transcriptome in earthworm Eisenia fetida

Directory of Open Access Journals (Sweden)

Vasanthakumar Ponesakki

2017-12-01

Full Text Available In annelid worms, the nerve cord serves as a crucial organ to control the sensory and behavioral physiology. The inadequate genome resource of earthworms has prioritized the comprehensive analysis of their transcriptome dataset to monitor the genes express in the nerve cord and predict their role in the neurotransmission and sensory perception of the species. The present study focuses on identifying the potential transcripts and predicting their functional features by annotating the transcriptome dataset of nerve cord tissues prepared by Gong et al., 2010 from the earthworm Eisenia fetida. Totally 9762 transcripts were successfully annotated against the NCBI nr database using the BLASTX algorithm and among them 7680 transcripts were assigned to a total of 44,354 GO terms. The conserve domain analysis indicated the over representation of P-loop NTPase domain and calcium binding EF-hand domain. The COG functional annotation classified 5860 transcript sequences into 25 functional categories. Further, 4502 contig sequences were found to map with 124 KEGG pathways. The annotated contig dataset exhibited 22 crucial neuropeptides having considerable matches to the marine annelid Platynereis dumerilii, suggesting their possible role in neurotransmission and neuromodulation. In addition, 108 human stem cell marker homologs were identified including the crucial epigenetic regulators, transcriptional repressors and cell cycle regulators, which may contribute to the neuronal and segmental regeneration. The complete functional annotation of this nerve cord transcriptome can be further utilized to interpret genetic and molecular mechanisms associated with neuronal development, nervous system regeneration and nerve cord function.

The chemokine CXCL12 mediates the anti-amyloidogenic action of painless human nerve growth factor.

Science.gov (United States)

Capsoni, Simona; Malerba, Francesca; Carucci, Nicola Maria; Rizzi, Caterina; Criscuolo, Chiara; Origlia, Nicola; Calvello, Mariantonietta; Viegi, Alessandro; Meli, Giovanni; Cattaneo, Antonino

2017-01-01

Nerve growth factor is a therapeutic candidate for Alzheimer's disease. Due to its pain-inducing activity, in current clinical trials nerve growth factor is delivered locally into the brain by neurosurgery, but data on the efficacy of local nerve growth factor delivery in decreasing amyloid-β deposition are not available. To reduce the nerve growth factor pain-inducing side effects, thus avoiding the need for local brain injection, we developed human painless nerve growth factor (hNGFp), inspired by the human genetic disease hereditary sensory and autonomic neuropathy type V. hNGFp has identical neurotrophic potency as wild-type human nerve growth factor, but a 10-fold lower pain sensitizing activity. In this study we first mimicked, in the 5xFAD mouse model, the intraparenchymal delivery of hNGFp used in clinical trials and found it to be ineffective in decreasing amyloid-β plaque load. On the contrary, the same dose of hNGFp delivered intranasally, which was widely biodistributed in the brain and did not induce pain, showed a potent anti-amyloidogenic action and rescued synaptic plasticity and memory deficits. We found that hNGFp acts on glial cells, modulating inflammatory proteins such as the soluble TNFα receptor II and the chemokine CXCL12. We further established that the rescuing effect by hNGFp is mediated by CXCL12, as pharmacological inhibition of CXCL12 receptor CXCR4 occludes most of hNGFp effects. These findings have significant therapeutic implications: (i) we established that a widespread exposure of the brain is required for nerve growth factor to fully exert its neuroprotective actions; and (ii) we have identified a new anti-neurodegenerative pathway as a broad target for new therapeutic opportunities for neurodegenerative diseases. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain.

The Association between Serum Cytokines and Damage to Large and Small Nerve Fibers in Diabetic Peripheral Neuropathy

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Francesca Magrinelli

2015-01-01

Full Text Available Diabetic peripheral neuropathy (DPN is a frequent complication of type 2 diabetes mellitus (DM and may involve small and large peripheral nerve fibers. Recent evidence suggests a role of cytokines in DPN. The paper is aimed at exploring whether the serum concentration of cytokines is associated with small and large nerve fiber function and with neuropathic pain (NP. We recruited a group of 32 type 2 DM patients who underwent serum cytokines (TNF-α, IL-2, IL-4, IL-6, and IL-10 dosage as well as electrodiagnostic and quantitative sensory testing (QST assessment to explore damage to large and small nerve fibers. Raised serum levels of IL-6 and IL-10 correlated with markers of large nerve fiber sensory and motor axonal damage. Raised IL-10 serum level was associated with signs of motor nerve demyelination. No differences were found in pain characteristics and electrodiagnostic and QST markers of small nerve fiber function in relation to cytokines serum levels. IL-6 and IL-10 serum levels were associated with large nerve fiber damage but not to small fibers function or NP. IL-6 and IL-10 cytokines might play a role in the pathogenesis of nerve fiber damage or represent a compensatory or neuroprotective mechanism.

Cutaneous somatic and autonomic nerve TDP-43 deposition in amyotrophic lateral sclerosis.

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Ren, Yuting; Liu, Wenxiu; Li, Yifan; Sun, Bo; Li, Yanran; Yang, Fei; Wang, Hongfen; Li, Mao; Cui, Fang; Huang, Xusheng

2018-05-26

To evaluate the involvement of the sensory and autonomic nervous system in amyotrophic lateral sclerosis (ALS) and to determine whether TDP-43/pTDP-43 deposits in skin nerve fibers signify a valuable biomarker for ALS. Eighteen patients with ALS and 18 age- and sex-matched control subjects underwent physical examinations, in addition to donating skin biopsies from the distal leg. The density of epidermal, Meissner's corpuscle (MC), sudomotor, and pilomotor nerve fibers were measured. Confocal microscopy was used to determine the cutaneous somatic and autonomic nerve fiber density and TDP-43/pTDP-43 deposition. Intraepidermal nerve fiber density (IENFD) was reduced in individuals with ALS (P nerve fiber density (SGNFD) (P nerve fiber density (PNFD) (P nerve fibers may indicate an important role in the underlying pathogenesis of ALS. This observation might be used as a potential biomarker for diagnosing ALS.

Regulating cough through modulation of sensory nerve function in the airways.

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Spina, D; Page, C P

2013-10-01

Whilst local anaesthetics when applied directly to laryngeal nerves or topically to the lung can suppress cough, their chronic use is constrained because of dose limiting side effects. However, the effectiveness of local anaesthetics suggests that selectivity targeting nerves in the airway may provide novel approaches for the treatment of cough in the future. There is a considerable wealth of evidence showing that there are different afferent nerve subtypes in the airways. Traditionally C-fibres have been the focus of much research in the cough field since the stimulation of these afferents by capsaicin is able to elicit cough in guinea-pigs and in man, and drugs targeting various proteins expressed in these nerves (e.g. mu-opioid, NOP1, TRPV1, sodium channels) have been shown to be anti-tussive in preclinical models of cough. However, interest in Aδ fibres has increased recently in light of the discovery of a specific cough receptor in the guinea-pig that is provoked by citric acid and punctate stimulation, but not capsaicin and which has been anatomically linked to Aδ fibres. There is also some evidence that as a result of inflammation in the airways, Aδ fibres can begin to express neuropeptides and TRPV1 receptors so that they can become responsive to endogenous activators of this ion channel and to irritants like capsaicin. Consequently, there is considerable interest in targeting either one or both afferent nerve types for the treatment of chronic cough. However, to date the translation of preclinical studies into man has largely been disappointing and certainly there is a need for better preclinical models in this field. There also remain many challenges to overcome at a clinical level, such as what patient group(s) should be used to assess anti-tussive drugs and whether the use of irritants that induce cough in healthy volunteers (such as citric acid or capsaicin) is of any value in the assessment of novel anti-tussive drugs. The development of several

The morphological substrate for Renal Denervation: Nerve distribution patterns and parasympathetic nerves. A post-mortem histological study.

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van Amsterdam, Wouter A C; Blankestijn, Peter J; Goldschmeding, Roel; Bleys, Ronald L A W

2016-03-01

Renal Denervation as a possible treatment for hypertension has been studied extensively, but knowledge on the distribution of nerves surrounding the renal artery is still incomplete. While sympathetic and sensory nerves have been demonstrated, there is no mention of the presence of parasympathetic nerve fibers. To provide a description of the distribution patterns of the renal nerves in man, and, in addition, provide a detailed representation of the relative contribution of the sympathetic, parasympathetic and afferent divisions of the autonomic nervous system. Renal arteries of human cadavers were each divided into four longitudinal segments and immunohistochemically stained with specific markers for afferent, parasympathetic and sympathetic nerves. Nerve fibers were semi-automatically quantified by computerized image analysis, and expressed as cross-sectional area relative to the distance to the lumen. A total of 3372 nerve segments were identified in 8 arteries of 7 cadavers. Sympathetic, parasympathetic and afferent nerves contributed for 73.5% (95% CI: 65.4-81.5%), 17.9% (10.7-25.1%) and 8.7% (5.0-12.3%) of the total cross-sectional nerve area, respectively. Nerves are closer to the lumen in more distal segments and larger bundles that presumably innervate the kidney lie at 1-3.5mm distance from the lumen. The tissue-penetration depth of the ablation required to destroy 50% of the nerve fibers is 2.37 mm in the proximal segment and 1.78 mm in the most distal segments. Sympathetic, parasympathetic and afferent nerves exist in the vicinity of the renal artery. The results warrant further investigation of the role of the parasympathetic nervous system on renal physiology, and may contribute to refinement of the procedure by focusing the ablation on the most distal segment. Copyright © 2015 Elsevier GmbH. All rights reserved.

Peripheral axotomy of the rat mandibular trigeminal nerve leads to an increase in VIP and decrease of other primary afferent neuropeptides in the spinal trigeminal nucleus.

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Atkinson, M E; Shehab, S A

1986-12-01

In the vasoactive intestinal polypeptide (VIP)-rich lumbosacral spinal cord, VIP increases at the expense of other neuropeptides after primary sensory nerve axotomy. This study was undertaken to ascertain whether similar changes occur in peripherally axotomised cranial sensory nerves. VIP immunoreactivity increased in the terminal region of the mandibular nerve in the trigeminal nucleus caudalis following unilateral section of the sensory root of the mandibular trigeminal nerve at the foramen orale. Other primary afferent neuropeptides (substance P, cholecystokinin and somatostatin) were depleted and fluoride-resistant acid phosphatase activity was abolished in the same circumscribed areas of the nucleus caudalis. The rise in VIP and depletion of other markers began 4 days postoperatively and was maximal by 10 days, these levels remaining unchanged up to 1 year postoperatively. VIP-immunoreactive cell bodies were absent from trigeminal ganglia from the unoperated side but small and medium cells stained intensely in the ganglia of the operated side after axotomy. These observations indicate that increase of VIP in sensory nerve terminals is a general phenomenon occurring in both cranial and spinal sensory terminal areas. The intense VIP immunoreactivity in axotomised trigeminal ganglia suggests that the increased levels of VIP in the nucleus caudalis are of peripheral origin, indicating a change in expression of neuropeptides within primary afferent neurons following peripheral axotomy.

Sensory and Motor Peripheral Nerve Function and Incident Mobility Disability

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Ward, R. E.; Boudreau, R. M.; Caserotti, P.

2014-01-01

ObjectivesTo assess the relationship between sensorimotor nerve function and incident mobility disability over 10years. DesignProspective cohort study with longitudinal analysis. SettingTwo U.S. clinical sites. ParticipantsPopulation-based sample of community-dwelling older adults with no mobility...

Differences in two-point discrimination and sensory threshold in the blind between braille and text reading: a pilot study.

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Noh, Ji-Woong; Park, Byoung-Sun; Kim, Mee-Young; Lee, Lim-Kyu; Yang, Seung-Min; Lee, Won-Deok; Shin, Yong-Sub; Kang, Ji-Hye; Kim, Ju-Hyun; Lee, Jeong-Uk; Kwak, Taek-Yong; Lee, Tae-Hyun; Kim, Ju-Young; Kim, Junghwan

2015-06-01

[Purpose] This study investigated two-point discrimination (TPD) and the electrical sensory threshold of the blind to define the effect of using Braille on the tactile and electrical senses. [Subjects and Methods] Twenty-eight blind participants were divided equally into a text-reading and a Braille-reading group. We measured tactile sensory and electrical thresholds using the TPD method and a transcutaneous electrical nerve stimulator. [Results] The left palm TPD values were significantly different between the groups. The values of the electrical sensory threshold in the left hand, the electrical pain threshold in the left hand, and the electrical pain threshold in the right hand were significantly lower in the Braille group than in the text group. [Conclusion] These findings make it difficult to explain the difference in tactility between groups, excluding both palms. However, our data show that using Braille can enhance development of the sensory median nerve in the blind, particularly in terms of the electrical sensory and pain thresholds.

The Proximal Medial Sural Nerve Biopsy Model: A Standardised and Reproducible Baseline Clinical Model for the Translational Evaluation of Bioengineered Nerve Guides

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Ahmet Bozkurt

2014-01-01

Full Text Available Autologous nerve transplantation (ANT is the clinical gold standard for the reconstruction of peripheral nerve defects. A large number of bioengineered nerve guides have been tested under laboratory conditions as an alternative to the ANT. The step from experimental studies to the implementation of the device in the clinical setting is often substantial and the outcome is unpredictable. This is mainly linked to the heterogeneity of clinical peripheral nerve injuries, which is very different from standardized animal studies. In search of a reproducible human model for the implantation of bioengineered nerve guides, we propose the reconstruction of sural nerve defects after routine nerve biopsy as a first or baseline study. Our concept uses the medial sural nerve of patients undergoing diagnostic nerve biopsy (≥2 cm. The biopsy-induced nerve gap was immediately reconstructed by implantation of the novel microstructured nerve guide, Neuromaix, as part of an ongoing first-in-human study. Here we present (i a detailed list of inclusion and exclusion criteria, (ii a detailed description of the surgical procedure, and (iii a follow-up concept with multimodal sensory evaluation techniques. The proximal medial sural nerve biopsy model can serve as a preliminarynature of the injuries or baseline nerve lesion model. In a subsequent step, newly developed nerve guides could be tested in more unpredictable and challenging clinical peripheral nerve lesions (e.g., following trauma which have reduced comparability due to the different nature of the injuries (e.g., site of injury and length of nerve gap.

Is peroneal nerve injury associated with worse function after knee dislocation?

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Krych, Aaron J; Giuseffi, Steven A; Kuzma, Scott A; Stuart, Michael J; Levy, Bruce A

2014-09-01

Peroneal nerve palsy is a frequent and potentially disabling complication of multiligament knee dislocation, but little information exists on the degree to which patients recover motor or sensory function after this injury, and whether having this nerve injury--with or without complete recovery--is a predictor of inferior patient-reported outcome scores. The purposes of this study were to (1) report on motor and sensory recovery as well as patient-reported outcomes scores of patients with peroneal nerve injury from multiligament knee dislocation; (2) compare those endpoints between patients who had partial versus complete nerve injuries; and (3) compare patient-reported outcomes among patients who sustained peroneal nerve injuries after knee dislocation with a matched cohort of multiligament knee injuries without nerve injury. Thirty-two patients were identified, but five did not have 2-year followup and are excluded (16% lost to followup). Twenty-seven patients (24 male, three female) with peroneal nerve injury underwent multiligament knee reconstruction and were followed for 6.3 years (range, 2-18 years). Motor grades were assessed by examination and outcomes by International Knee Documentation Committee (IKDC) and Lysholm scores. Retrospectively, patients were divided into complete (n = 9) and partial nerve palsy (n = 18). Treatment for complete nerve palsy included an ankle-foot orthosis for all patients, nonoperative (one), neurolysis (two), tendon transfer (three), nerve transfer (one), and combined nerve/tendon transfer (one). Treatment for partial nerve palsy included nonoperative (12), neurolysis (four), nerve transfer (one), and combined nerve/tendon transfer (one). Furthermore, patients without nerve injury were matched by Schenck classification, age, and sex. Data were analyzed using univariate and multivariate models. Overall, 18 patients (69%) regained antigravity ankle dorsiflexion after treatment (three complete nerve palsy [38%] versus 15 partial

The role of ultrasound imaging in the evaluation of peripheral nerve in systemic sclerosis (scleroderma)

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Tagliafico, Alberto; Panico, Nicoletta; Resmini, Eugenia; Derchi, Lorenzo E.; Ghio, Massimo; Martinoli, Carlo

2011-01-01

Background: Patients affected by scleroderma may complain of sensory disturbances especially in the hands. Purpose: To study the imaging features of upper limb nerves in patients affected by scleroderma (SSc). Materials and method: Twenty-five patients affected only by SSc were prospectively evaluated with high-resolution US and magnetic resonance (MRI) or computer tomography (CT) when necessary (2 patients). Median and ulnar nerves were evaluated bilaterally. Nerve conduction studies were performed in the symptomatic patients (n = 10). Results of imaging studies were correlated with disease duration, autoimmunity and immunosuppression. Nerves of SSc patients were compared with a control group of 90 patients matched for age and body mass index. Results: The prevalence of sensory disturbances revealed by clinical examination was 40%. In symptomatic SSc patients (n = 10) US evaluation revealed nerve abnormalities in 70% of cases (n = 7/10). n = 2 had a carpal tunnel syndrome. n = 5 had cubital tunnel syndrome. In two of them CT and MR were necessary to identify the compressed nerve at the level of the elbow due to the presence of calcifications. There was no association between the presence of an entrapment neuropathy and disease duration, autoantibodies and immunosuppression. Conclusion: Ultrasound, CT and MR may detect nerve abnormalities in 70% of SSc patients complaining of neurologic disturbances in the hands. The results of imaging studies support the hypothesis of a vascular dependent neuropathy in SSc.

The role of ultrasound imaging in the evaluation of peripheral nerve in systemic sclerosis (scleroderma)

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Tagliafico, Alberto, E-mail: atagliafico@sirm.org [Department of Radiology, University of Genova, Genova (Italy); Panico, Nicoletta [Division of Immunology, Department of Internal Medicine, University of Genoa, Genoa (Italy); Resmini, Eugenia [Department of Endocrinological and Medical Sciences (DiSEM), Center of Excellence for Biomedical Research, University of Genova, Genova (Italy); Derchi, Lorenzo E. [Department of Radiology, University of Genova, Genova (Italy); Ghio, Massimo [Division of Immunology, Department of Internal Medicine, University of Genoa, Genoa (Italy); Martinoli, Carlo [Department of Radiology, University of Genova, Genova (Italy)

2011-03-15

Background: Patients affected by scleroderma may complain of sensory disturbances especially in the hands. Purpose: To study the imaging features of upper limb nerves in patients affected by scleroderma (SSc). Materials and method: Twenty-five patients affected only by SSc were prospectively evaluated with high-resolution US and magnetic resonance (MRI) or computer tomography (CT) when necessary (2 patients). Median and ulnar nerves were evaluated bilaterally. Nerve conduction studies were performed in the symptomatic patients (n = 10). Results of imaging studies were correlated with disease duration, autoimmunity and immunosuppression. Nerves of SSc patients were compared with a control group of 90 patients matched for age and body mass index. Results: The prevalence of sensory disturbances revealed by clinical examination was 40%. In symptomatic SSc patients (n = 10) US evaluation revealed nerve abnormalities in 70% of cases (n = 7/10). n = 2 had a carpal tunnel syndrome. n = 5 had cubital tunnel syndrome. In two of them CT and MR were necessary to identify the compressed nerve at the level of the elbow due to the presence of calcifications. There was no association between the presence of an entrapment neuropathy and disease duration, autoantibodies and immunosuppression. Conclusion: Ultrasound, CT and MR may detect nerve abnormalities in 70% of SSc patients complaining of neurologic disturbances in the hands. The results of imaging studies support the hypothesis of a vascular dependent neuropathy in SSc.

Hispidulin inhibits the release of glutamate in rat cerebrocortical nerve terminals

International Nuclear Information System (INIS)

Lin, Tzu-Yu; Lu, Cheng-Wei; Wang, Chia-Chuan; Lu, Jyh-Feng; Wang, Su-Jane

2012-01-01

Hispidulin, a naturally occurring flavone, has been reported to have an antiepileptic profile. An excessive release of glutamate is considered to be related to neuropathology of epilepsy. We investigated whether hispidulin affected endogenous glutamate release in rat cerebral cortex nerve terminals (synaptosomes) and explored the possible mechanism. Hispidulin inhibited the release of glutamate evoked by the K + channel blocker 4-aminopyridine (4-AP). The effects of hispidulin on the evoked glutamate release were prevented by the chelation of extracellular Ca 2+ ions and the vesicular transporter inhibitor bafilomycin A1. However, the glutamate transporter inhibitor DL-threo-beta-benzyl-oxyaspartate did not have any effect on hispidulin action. Hispidulin reduced the depolarization-induced increase in cytosolic free Ca 2+ concentration ([Ca 2+ ] C ), but did not alter 4-AP-mediated depolarization. Furthermore, the effect of hispidulin on evoked glutamate release was abolished by blocking the Ca v 2.2 (N-type) and Ca v 2.1 (P/Q-type) channels, but not by blocking ryanodine receptors or mitochondrial Na + /Ca 2+ exchange. Mitogen-activated protein kinase kinase (MEK) inhibition also prevented the inhibitory effect of hispidulin on evoked glutamate release. Western blot analyses showed that hispidulin decreased the 4-AP-induced phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2) and synaptic vesicle-associated protein synapsin I, a major presynaptic substrate for ERK; this decrease was also blocked by the MEK inhibitor. Moreover, the inhibition of glutamate release by hispidulin was strongly attenuated in mice without synapsin I. These results show that hispidulin inhibits glutamate release from cortical synaptosomes in rats through the suppression of presynaptic voltage-dependent Ca 2+ entry and ERK/synapsin I signaling pathway. -- Highlights: ► Hispidulin inhibited glutamate release from rat cerebrocortical synaptosomes. ► This action did

Hispidulin inhibits the release of glutamate in rat cerebrocortical nerve terminals

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Lin, Tzu-Yu [Department of Anesthesiology, Far-Eastern Memorial Hospital, Pan-Chiao District, New Taipei, 22060, Taiwan (China); Department of Mechanical Engineering, Yuan Ze University, Taoyuan, 320, Taiwan (China); Lu, Cheng-Wei [Department of Anesthesiology, Far-Eastern Memorial Hospital, Pan-Chiao District, New Taipei, 22060, Taiwan (China); Wang, Chia-Chuan; Lu, Jyh-Feng [School of Medicine, Fu Jen Catholic University, No.510, Zhongzheng Rd., Xinzhuang Dist., New Taipei, 24205, Taiwan (China); Wang, Su-Jane, E-mail: med0003@mail.fju.edu.tw [Graduate Institute of Basic Medicine, Fu Jen Catholic University, No.510, Zhongzheng Rd., Xinzhuang Dist., New Taipei, 24205, Taiwan (China); School of Medicine, Fu Jen Catholic University, No.510, Zhongzheng Rd., Xinzhuang Dist., New Taipei, 24205, Taiwan (China)

2012-09-01

Hispidulin, a naturally occurring flavone, has been reported to have an antiepileptic profile. An excessive release of glutamate is considered to be related to neuropathology of epilepsy. We investigated whether hispidulin affected endogenous glutamate release in rat cerebral cortex nerve terminals (synaptosomes) and explored the possible mechanism. Hispidulin inhibited the release of glutamate evoked by the K{sup +} channel blocker 4-aminopyridine (4-AP). The effects of hispidulin on the evoked glutamate release were prevented by the chelation of extracellular Ca{sup 2+} ions and the vesicular transporter inhibitor bafilomycin A1. However, the glutamate transporter inhibitor DL-threo-beta-benzyl-oxyaspartate did not have any effect on hispidulin action. Hispidulin reduced the depolarization-induced increase in cytosolic free Ca{sup 2+} concentration ([Ca{sup 2+}]{sub C}), but did not alter 4-AP-mediated depolarization. Furthermore, the effect of hispidulin on evoked glutamate release was abolished by blocking the Ca{sub v}2.2 (N-type) and Ca{sub v}2.1 (P/Q-type) channels, but not by blocking ryanodine receptors or mitochondrial Na{sup +}/Ca{sup 2+} exchange. Mitogen-activated protein kinase kinase (MEK) inhibition also prevented the inhibitory effect of hispidulin on evoked glutamate release. Western blot analyses showed that hispidulin decreased the 4-AP-induced phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2) and synaptic vesicle-associated protein synapsin I, a major presynaptic substrate for ERK; this decrease was also blocked by the MEK inhibitor. Moreover, the inhibition of glutamate release by hispidulin was strongly attenuated in mice without synapsin I. These results show that hispidulin inhibits glutamate release from cortical synaptosomes in rats through the suppression of presynaptic voltage-dependent Ca{sup 2+} entry and ERK/synapsin I signaling pathway. -- Highlights: ► Hispidulin inhibited glutamate release from rat

Autosomal recessive type II hereditary motor and sensory neuropathy with acrodystrophy.

Science.gov (United States)

Thomas, P K; Claus, D; King, R H

1999-02-01

A family is described with presumed autosomal recessive inheritance in which three siblings developed a progressive neuropathy that combined limb weakness and severe distal sensory loss leading to prominent mutilating changes. Electrophysiological and nerve biopsy findings indicated an axonopathy. The disorder is therefore classifiable as type II hereditary motor and sensory neuropathy (HMSN II). The clinical features differ from those reported in previously described cases of autosomal recessive HMSN II. This disorder may therefore represent a new variant.

Circuit motifs for contrast-adaptive differentiation in early sensory systems: the role of presynaptic inhibition and short-term plasticity.

Science.gov (United States)

Zhang, Danke; Wu, Si; Rasch, Malte J

2015-01-01

In natural signals, such as the luminance value across of a visual scene, abrupt changes in intensity value are often more relevant to an organism than intensity values at other positions and times. Thus to reduce redundancy, sensory systems are specialized to detect the times and amplitudes of informative abrupt changes in the input stream rather than coding the intensity values at all times. In theory, a system that responds transiently to fast changes is called a differentiator. In principle, several different neural circuit mechanisms exist that are capable of responding transiently to abrupt input changes. However, it is unclear which circuit would be best suited for early sensory systems, where the dynamic range of the natural input signals can be very wide. We here compare the properties of different simple neural circuit motifs for implementing signal differentiation. We found that a circuit motif based on presynaptic inhibition (PI) is unique in a sense that the vesicle resources in the presynaptic site can be stably maintained over a wide range of stimulus intensities, making PI a biophysically plausible mechanism to implement a differentiator with a very wide dynamical range. Moreover, by additionally considering short-term plasticity (STP), differentiation becomes contrast adaptive in the PI-circuit but not in other potential neural circuit motifs. Numerical simulations show that the behavior of the adaptive PI-circuit is consistent with experimental observations suggesting that adaptive presynaptic inhibition might be a good candidate neural mechanism to achieve differentiation in early sensory systems.

Inhibition of 2-arachydonoylgycerol degradation attenuates orofacial neuropathic pain in trigeminal nerve-injured mice.

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Kamimura, Rantaro; Hossain, Mohammad Z; Unno, Shumpei; Ando, Hiroshi; Masuda, Yuji; Takahashi, Kojiro; Otake, Masanori; Saito, Isao; Kitagawa, Junichi

2018-03-24

Current therapeutics are not effective for orofacial neuropathic pain, and better options are needed. The present study used inferior orbital nerve (ION)-injured mice to investigate the effect of inhibiting monoacylglycerol lipase (MAGL), an enzyme that degrades the major endocannabinoid 2-arachydonoylgycerol (2-AG) in orofacial neuropathic pain. The head-withdrawal threshold to mechanical stimulation of the whisker pad was reduced on days 3, 5, and 7 after ION injury. Injection of JZL184, a selective inhibitor of MAGL, on day 7 after ION injury attenuated the reduction in head-withdrawal threshold at 2 h after administration. Moreover, the numbers of MAGL-immunoreactive neurons in the trigeminal subnucleus caudalis (Vc) and upper cervical spinal cord (C1-C2) were significantly greater in ION-injured mice than in sham-operated mice but were reduced after administration of JZL184. The increase in MAGL immunoreactivity suggests that increased 2-AG production is followed by rapid enzymatic degradation of 2-AG. JZL184 inhibited this degradation and thus increased 2-AG concentration in the brain, particularly in the Vc and C1-C2 regions, thus attenuating pain. Our findings suggest that inhibition of 2-AG degradation by MAGL inhibitors is a promising therapeutic option for treatment of orofacial neuropathic pain.

Lentiviral-mediated transfer of CDNF promotes nerve regeneration and functional recovery after sciatic nerve injury in adult rats

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Cheng, Lei; Liu, Yi; Zhao, Hua; Zhang, Wen; Guo, Ying-Jun; Nie, Lin, E-mail: chengleiyx@126.com

2013-10-18

Highlights: •CDNF was successfully transfected by a lentiviral vector into the distal sciatic nerve. •CDNF improved S-100, NF200 expression and nerve regeneration after sciatic injury. •CDNF improved the remyelination and thickness of the regenerated sciatic nerve. •CDNF improved gastrocnemius muscle weight and sciatic functional recovery. -- Abstract: Peripheral nerve injury is often followed by incomplete and unsatisfactory functional recovery and may be associated with sensory and motor impairment of the affected limb. Therefore, a novel method is needed to improve the speed of recovery and the final functional outcome after peripheral nerve injuries. This report investigates the effect of lentiviral-mediated transfer of conserved dopamine neurotrophic factor (CDNF) on regeneration of the rat peripheral nerve in a transection model in vivo. We observed notable overexpression of CDNF protein in the distal sciatic nerve after recombinant CDNF lentiviral vector application. We evaluated sciatic nerve regeneration after surgery using light and electron microscopy and the functional recovery using the sciatic functional index and target muscle weight. HE staining revealed better ordered structured in the CDNF-treated group at 8 weeks post-surgery. Quantitative analysis of immunohistochemistry of NF200 and S-100 in the CDNF group revealed significant improvement of axonal and Schwann cell regeneration compared with the control groups at 4 weeks and 8 weeks after injury. The thickness of the myelination around the axons in the CDNF group was significantly higher than in the control groups at 8 weeks post-surgery. The CDNF group displayed higher muscle weights and significantly increased sciatic nerve index values. Our findings suggest that CDNF gene therapy could provide durable and stable CDNF protein concentration and has the potential to enhance peripheral nerve regeneration, morphological and functional recovery following nerve injury, which suggests a

Lentiviral-mediated transfer of CDNF promotes nerve regeneration and functional recovery after sciatic nerve injury in adult rats

International Nuclear Information System (INIS)

Cheng, Lei; Liu, Yi; Zhao, Hua; Zhang, Wen; Guo, Ying-Jun; Nie, Lin

2013-01-01

Highlights: •CDNF was successfully transfected by a lentiviral vector into the distal sciatic nerve. •CDNF improved S-100, NF200 expression and nerve regeneration after sciatic injury. •CDNF improved the remyelination and thickness of the regenerated sciatic nerve. •CDNF improved gastrocnemius muscle weight and sciatic functional recovery. -- Abstract: Peripheral nerve injury is often followed by incomplete and unsatisfactory functional recovery and may be associated with sensory and motor impairment of the affected limb. Therefore, a novel method is needed to improve the speed of recovery and the final functional outcome after peripheral nerve injuries. This report investigates the effect of lentiviral-mediated transfer of conserved dopamine neurotrophic factor (CDNF) on regeneration of the rat peripheral nerve in a transection model in vivo. We observed notable overexpression of CDNF protein in the distal sciatic nerve after recombinant CDNF lentiviral vector application. We evaluated sciatic nerve regeneration after surgery using light and electron microscopy and the functional recovery using the sciatic functional index and target muscle weight. HE staining revealed better ordered structured in the CDNF-treated group at 8 weeks post-surgery. Quantitative analysis of immunohistochemistry of NF200 and S-100 in the CDNF group revealed significant improvement of axonal and Schwann cell regeneration compared with the control groups at 4 weeks and 8 weeks after injury. The thickness of the myelination around the axons in the CDNF group was significantly higher than in the control groups at 8 weeks post-surgery. The CDNF group displayed higher muscle weights and significantly increased sciatic nerve index values. Our findings suggest that CDNF gene therapy could provide durable and stable CDNF protein concentration and has the potential to enhance peripheral nerve regeneration, morphological and functional recovery following nerve injury, which suggests a

Where are the sensory organs of Nybelinia surmenicola (Trypanorhyncha)? A comparative analysis with Parachristianella sp. and other trypanorhynchean cestodes.

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Biserova, Natalia M; Gordeev, Ilya I; Korneva, Janetta V

2016-01-01

The sensory organs in tegument of two trypanorhynchean species--Nybelinia surmenicola (plerocercoid) and adult Parachristianella sp. (Cestoda, Trypanorhyncha)--were studied with the aim of ultrastructural description and a comparative analysis. The Nybelinia surmenicola plerocercoid lacks papillae with sensory cilia on the bothria adhesive surface. We found an unciliated sensory organ within the median bothria fold. This unciliated free nerve ending contains the central electron-dense disc, three dense supporting rings, and broad root. The nerve ending locates in the basal matrix under the tegument. The tegument of N. surmenicola has a number of ultrastructural features which make it significantly different from other Trypanorhyncha: (i) the tegumental cytoplasm has a plicated constitution in a form of high apical and deep basal folds, (ii) numerous layers of the basal matrix are presented in the subtegument, and (iii) the squamiform and bristlelike microtriches N. surmenicola lack the base and the basal plate. In contrast, numerous ciliated and unciliated receptors were found in Parachristianella sp.: six types on the bothria and one type in the strobila tegument. Ultrastructural constitution of sensory organs in the form of ciliated free nerve endings as well as unciliated basal nerve endings of Parachristianella sp. has many common features inside Eucestoda. In comparison with other Trypanorhyncha, all Nybelinia species studied have less quantity of the bothrial sensory organs. This fact may reflect behavioral patterns of Nybelinia as well as phylogenetic position into Trypanorhyncha. Our observations of living animals conventionally demonstrate the ability of N. surmenicola plerocercoids to locomote in forward direction on the Petri dish surface. The participation of the bothrial microtriches in a parasite movement has been discussed.

Brief electrical stimulation improves nerve regeneration after delayed repair in Sprague Dawley rats.

Science.gov (United States)

Elzinga, Kate; Tyreman, Neil; Ladak, Adil; Savaryn, Bohdan; Olson, Jaret; Gordon, Tessa

2015-07-01

Functional recovery after peripheral nerve injury and surgical repair declines with time and distance because the injured neurons without target contacts (chronic axotomy) progressively lose their regenerative capacity and chronically denervated Schwann cells (SCs) atrophy and fail to support axon regeneration. Findings that brief low frequency electrical stimulation (ES) accelerates axon outgrowth and muscle reinnervation after immediate nerve surgery in rats and human patients suggest that ES might improve regeneration after delayed nerve repair. To test this hypothesis, common peroneal (CP) neurons were chronically axotomized and/or tibial (TIB) SCs and ankle extensor muscles were chronically denervated by transection and ligation in rats. The CP and TIB nerves were cross-sutured after three months and subjected to either sham or one hour 20Hz ES. Using retrograde tracing, we found that ES significantly increased the numbers of both motor and sensory neurons that regenerated their axons after a three month period of chronic CP axotomy and/or chronic TIB SC denervation. Muscle and motor unit forces recorded to determine the numbers of neurons that reinnervated gastrocnemius muscle demonstrated that ES significantly increased the numbers of motoneurons that reinnervated chronically denervated muscles. We conclude that electrical stimulation of chronically axotomized motor and sensory neurons is effective in accelerating axon outgrowth into chronically denervated nerve stumps and improving target reinnervation after delayed nerve repair. Possible mechanisms for the efficacy of ES in promoting axon regeneration and target reinnervation after delayed nerve repair include the upregulation of neurotrophic factors. Copyright © 2015 Elsevier Inc. All rights reserved.

Complex Sensory Corpuscles in the Upper Jaw of Horsfield’s Tortoise (Testudo horsfieldii

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Marcela Buchtová

2009-01-01

Full Text Available The sensory corpuscles of Testudo horsfieldii in the skin of the upper lip and face were studied with light and electron microscopy. The sensory corpuscles were situated under epidermis; in the corium and also between the upper jaw bone tissues in the rostral part of oral cavity. The skin sensory corpuscles with a ramified inner core were grouped in clusters. Within the corpuscle there were several simple inner cores embedded within a common superficial capsule. The complex corpuscles have a novel structure in comparison to what has been described for sensory nerve endings in turtle. The complex sensory corpuscles probably function as mechanoreceptors important for monitoring the movement of the keratinized ridges and the most rostral part of the upper jaw, the rhamphotheci.

Morphology and intrinsic excitability of regenerating sensory and motor neurons grown on a line micropattern.

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Ouafa Benzina

Full Text Available Axonal regeneration is one of the greatest challenges in severe injuries of peripheral nerve. To provide the bridge needed for regeneration, biological or synthetic tubular nerve constructs with aligned architecture have been developed. A key point for improving axonal regeneration is assessing the effects of substrate geometry on neuronal behavior. In the present study, we used an extracellular matrix-micropatterned substrate comprising 3 µm wide lines aimed to physically mimic the in vivo longitudinal axonal growth of mice peripheral sensory and motor neurons. Adult sensory neurons or embryonic motoneurons were seeded and processed for morphological and electrical activity analyses after two days in vitro. We show that micropattern-guided sensory neurons grow one or two axons without secondary branching. Motoneurons polarity was kept on micropattern with a long axon and small dendrites. The micro-patterned substrate maintains the growth promoting effects of conditioning injury and demonstrates, for the first time, that neurite initiation and extension could be differentially regulated by conditioning injury among DRG sensory neuron subpopulations. The micro-patterned substrate impacts the excitability of sensory neurons and promotes the apparition of firing action potentials characteristic for a subclass of mechanosensitive neurons. The line pattern is quite relevant for assessing the regenerative and developmental growth of sensory and motoneurons and offers a unique model for the analysis of the impact of geometry on the expression and the activity of mechanosensitive channels in DRG sensory neurons.

Sensory and Motor Peripheral Nerve Function and Longitudinal Changes in Quadriceps Strength

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Ward, R. E.; Boudreau, R. M.; Caserotti, P.

2015-01-01

Background. Poor peripheral nerve function is common in older adults and may be a risk factor for strength decline, although this has not been assessed longitudinally. Methods. We assessed whether sensorimotor peripheral nerve function predicts strength longitudinally in 1,830 participants (age...... was assessed with 10-g and 1.4-g monofilaments and average vibration detection threshold at the toe. Lower-extremity neuropathy symptoms were self-reported. Results. Worse vibration detection threshold predicted 2.4% lower strength in men and worse motor amplitude and two symptoms predicted 2.5% and 8.1% lower...

Adductor Canal Block versus Femoral Nerve Block and Quadriceps Strength

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Jæger, Pia Therese; Nielsen, Zbigniew Jerzy Koscielniak; Henningsen, Lene Marianne

2013-01-01

: The authors hypothesized that the adductor canal block (ACB), a predominant sensory blockade, reduces quadriceps strength compared with placebo (primary endpoint, area under the curve, 0.5-6 h), but less than the femoral nerve block (FNB; secondary endpoint). Other secondary endpoints were...

Cornea nerve fiber quantification and construction of phenotypes in patients with fibromyalgia.

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Oudejans, Linda; He, Xuan; Niesters, Marieke; Dahan, Albert; Brines, Michael; van Velzen, Monique

2016-03-23

Cornea confocal microscopy (CCM) is a novel non-invasive method to detect small nerve fiber pathology. CCM generally correlates with outcomes of skin biopsies in patients with small fiber pathology. The aim of this study was to quantify the morphology of small nerve fibers of the cornea of patients with fibromyalgia in terms of density, length and branching and further phenotype these patients using standardized quantitative sensory testing (QST). Small fiber pathology was detected in the cornea of 51% of patients: nerve fiber length was significantly decreased in 44% of patients compared to age- and sex-matched reference values; nerve fiber density and branching were significantly decreased in 10% and 28% of patients. The combination of the CCM parameters and sensory tests for central sensitization, (cold pain threshold, mechanical pain threshold, mechanical pain sensitivity, allodynia and/or windup), yielded four phenotypes of fibromyalgia patients in a subgroup analysis: one group with normal cornea morphology without and with signs of central sensitization, and a group with abnormal cornea morphology parameters without and with signs of central sensitization. In conclusion, half of the tested fibromyalgia population demonstrates signs of small fiber pathology as measured by CCM. The four distinct phenotypes suggest possible differences in disease mechanisms and may require different treatment approaches.

Peripheral nerve conduits: technology update

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Arslantunali D

2014-12-01

Full Text Available D Arslantunali,1–3,* T Dursun,1,2,* D Yucel,1,4,5 N Hasirci,1,2,6 V Hasirci,1,2,7 1BIOMATEN, Center of Excellence in Biomaterials and Tissue Engineering, Middle East Technical University (METU, Ankara, Turkey; 2Department of Biotechnology, METU, Ankara, Turkey; 3Department of Bioengineering, Gumushane University, Gumushane, Turkey; 4Faculty of Engineering, Department of Medical Engineering, Acibadem University, Istanbul, Turkey; 5School of Medicine, Department of Histology and Embryology, Acibadem University, Istanbul, Turkey; 6Department of Chemistry, Faculty of Arts and Sciences, METU, Ankara, Turkey; 7Department of Biological Sciences, Faculty of Arts and Sciences, METU, Ankara, Turkey *These authors have contributed equally to this work Abstract: Peripheral nerve injury is a worldwide clinical problem which could lead to loss of neuronal communication along sensory and motor nerves between the central nervous system (CNS and the peripheral organs and impairs the quality of life of a patient. The primary requirement for the treatment of complete lesions is a tension-free, end-to-end repair. When end-to-end repair is not possible, peripheral nerve grafts or nerve conduits are used. The limited availability of autografts, and drawbacks of the allografts and xenografts like immunological reactions, forced the researchers to investigate and develop alternative approaches, mainly nerve conduits. In this review, recent information on the various types of conduit materials (made of biological and synthetic polymers and designs (tubular, fibrous, and matrix type are being presented. Keywords: peripheral nerve injury, natural biomaterials, synthetic biomaterials

Occurrence of substance P-like immunoreactive nerve fibers in Krause corpuscles of the dog's tongue.

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Ichikawa, H; Nishikawa, S; Wakisaka, S; Matsuo, S; Takano, Y; Akai, M

1988-01-01

Substance P-like immunoreactive (SPLI) nerve fibers were demonstrated in the Krause corpuscles of the dog's tongue using the indirect immunofluorescence method and cholinesterase histochemistry. SPLI nerve fibers were often in contact with Krause end bulbs and occasionally entered them. From this result it was suggested that substance P might be involved in sensory mechanism of the Krause apparatus.

Increased Nerve Growth Factor Signaling in Sensory Neurons of Early Diabetic Rats Is Corrected by Electroacupuncture

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Stefania Lucia Nori

2013-01-01

Full Text Available Diabetic polyneuropathy (DPN, characterized by early hyperalgesia and increased nerve growth factor (NGF, evolves in late irreversible neuropathic symptoms with reduced NGF support to sensory neurons. Electroacupuncture (EA modulates NGF in the peripheral nervous system, being effective for the treatment of DPN symptoms. We hypothesize that NGF plays an important pathogenic role in DPN development, while EA could be useful in the therapy of DPN by modulating NGF expression/activity. Diabetes was induced in rats by streptozotocin (STZ injection. One week after STZ, EA was started and continued for three weeks. NGF system and hyperalgesia-related mediators were analyzed in the dorsal root ganglia (DRG and in their spinal cord and skin innervation territories. Our results show that four weeks long diabetes increased NGF and NGF receptors and deregulated intracellular signaling mediators of DRG neurons hypersensitization; EA in diabetic rats decreased NGF and NGF receptors, normalized c-Jun N-terminal and p38 kinases activation, decreased transient receptor potential vanilloid-1 ion channel, and possibly activated the nuclear factor kappa-light-chain-enhancer of activated B cells (Nf-κB. In conclusion, NGF signaling deregulation might play an important role in the development of DPN. EA represents a supportive tool to control DPN development by modulating NGF signaling in diabetes-targeted neurons.

Spread of Injectate Around Hip Articular Sensory Branches of the Femoral Nerve in Cadavers

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Nielsen, Niels Dalsgaard; Greher, Manfred; Moriggl, Bernhard

2018-01-01

of the femoral nerve. Methods: Fifteen cadaver sides were injected with 5 mL dye in the iliopsoas plane guided by ultrasound. Dissection was performed to verify the spread of injectate around the hip articular branches of the femoral nerve. Results: In 10 dissections (67% [95% confidence interval: 38.......2-32%]) adhesions partially obstructed the spread of dye. Conclusion: An injection of 5 mL in the iliopsoas plane spreads around all hip articular branches of the femoral nerve in 10 of 15 cadaver sides. If these findings translate to living humans, injection of local anaesthetic into the iliopsoas plane could...

Electrophysiologic alterations in the excitability of the sciatic and vagus nerves during early stages of sepsis.

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Diniz, Lúcio Ricardo Leite; Portella, Viviane Gomes; da Silva Alves, Kerly Shamira; Araújo, Pâmella Cristina da Costa; de Albuquerque Júnior, Ricardo Luiz Cavalcanti; Cavalcante de Albuquerque, Aline Alice; Coelho-de-Souza, Andrelina Noronha; Leal-Cardoso, José Henrique

2018-01-01

Nonspecific and delayed diagnosis of neurologic damage contributes to the development of neuropathies in patients with severe sepsis. The present study assessed the electrophysiologic parameters related to the excitability and conductibility of sciatic and vagus nerves during early stages of sepsis. Twenty-four hours after sepsis induced by cecal ligation and puncture (CLP) model, sciatic and vagus nerves of septic (CLP group) and control (sham group) rats were removed, and selected electric stimulations were applied to measure the parameters of the first and second components of the compound action potential. The first component originated from fibers with motor and sensory functions (Types A α and A β fibers) with a large conduction velocity (70-120 m/s), and the second component originated from fibers (Type A γ ) with sensorial function. To evaluate the presence of sensorial alterations, the sensitivity to non-noxious mechanical stimuli was measured by using the von Frey test. Hematoxylin and eosin staining of the nerves was performed. We observed an increase of rheobase followed by a decrease in the first component amplitude and a higher paw withdrawal threshold in response to the application of von Frey filaments in sciatic nerves from the CLP group compared to the sham group. Differently, a decrease in rheobase and an increase in the first component amplitude of vagal C fibers from CLP group were registered. No significant morphologic alteration was observed. Our data showed that the electrophysiologic alterations in peripheral nerves vary with the fiber type and might be identified in the first 24 h of sepsis, before clinical signs of neuromuscular disorders.

Frequency of sensory motor neuropathy in type 2 diabetics

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Ather, N.A.; Sattar, R.A.; Ara, J.

2008-01-01

To determine the frequency of sensory motor neuropathy in type 2 diabetics at the time of presentation to the hospital. The study was conducted at Medical Unit-1, Jinnah Postgraduate Medical Center, Karachi, from November 2005 to April 2006. Patients of different ages and either gender with history of confirmed diabetes for ten years and above, on regular follow up were included. Those with non-diabetic causes of hyperglycemia or neuropathy were excluded. Relevant features like age, gender, treatment, symptoms , signs, nerve conduction study (NCS) results, duration of Diabetes mellitus (DM), fasting blood sugar (FBS) and serum values of glycosylated hemoglobin (HB1Ac) were recorded. Out of a total of 300 patients, there were 111 female and 189 male patients. Mean age was 58 +- 11.23 years. Mean duration of diabetes was 13.6+-5.48 years. One hundred and twenty three patients had symptoms of neuropathy. Clinical examination revealed mixed sensory and motor signs in 135 (45%) patients. Nerve conduction studies revealed abnormalities in 159 (53%) patients. Among patients having an abnormal NCS, the fasting blood glucose (FBS) was 120mg/dl in 147 (91%) patients. The glycosylated hemoglobin ranged from 4-15% with mean of 8.1% and standard deviation of 2.5%. This showed significant association (p <0.001) of peripheral neuropathy with abnormal FBS, HB1Ac and duration of diabetes. NCS diagnosed the neuropathy in more than half of the total number of patients, including both symptomatic and asymptomatic patients. Majority of the patients revealed symmetrical and a mixed type (motor and sensory) polyneuropathy. This shows that nerve conduction may not be concordant with the clinical signs and symptoms. NCS detects neuropathy much earlier, before it becomes evident clinically. The neuropathy is associated with abonromal fasting blood sugar, HBIAC and duration of diabetes. (author)

Lingual nerve injury II. Observations on sensory recovery after micro-neurosurgical reconstruction

DEFF Research Database (Denmark)

Hillerup, S; Stoltze, Kaj

2007-01-01

/dull discrimination, warm, cold, location of touch, and brush stroke direction, pain perception and two-point discrimination. The rate of recovery was highest during the first 6 months. Females were more often affected than males, but recovery was not influenced by gender. The distribution of neurogenic discomfort......The aim of this study was to report on neurosensory recovery after micro-surgical lingual nerve repair, and to evaluate the effect on recovery of age, delay in repair and gender of the patient. Seventy-four patients entered the study. The micro-surgical repair performed was direct nerve suture (n...

Nerve regeneration with aid of nanotechnology and cellular engineering.

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Sedaghati, Tina; Yang, Shi Yu; Mosahebi, Afshin; Alavijeh, Mohammad S; Seifalian, Alexander M

2011-01-01

Repairing nerve defects with large gaps remains one of the most operative challenges for surgeons. Incomplete recovery from peripheral nerve injuries can produce a diversity of negative outcomes, including numbness, impairment of sensory or motor function, possibility of developing chronic pain, and devastating permanent disability. In the last few years, numerous microsurgical techniques, such as coaptation, nerve autograft, and different biological or polymeric nerve conduits, have been developed to reconstruct a long segment of damaged peripheral nerve. A few of these techniques are promising and have become popular among surgeons. Advancements in the field of tissue engineering have led to development of synthetic nerve conduits as an alternative for the nerve autograft technique, which is the current practice to bridge nerve defects with gaps larger than 30 mm. However, to date, despite significant progress in this field, no material has been found to be an ideal alternative to the nerve autograft. This article briefly reviews major up-to-date published studies using different materials as an alternative to the nerve autograft to bridge peripheral nerve gaps in an attempt to assess their ability to support and enhance nerve regeneration and their prospective drawbacks, and also highlights the promising hope for nerve regeneration with the next generation of nerve conduits, which has been significantly enhanced with the tissue engineering approach, especially with the aid of nanotechnology in development of the three-dimensional scaffold. The goal is to determine potential alternatives for nerve regeneration and repair that are simply and directly applicable in clinical conditions. Copyright © 2011 International Union of Biochemistry and Molecular Biology, Inc.

Stem cells and related factors involved in facial nerve function regeneration

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Kamil H. Nelke

2015-09-01

Full Text Available The facial nerve (VII is one of the most important cranial nerves for head and neck surgeons. Its function is closely related to facial expressions that are individual for every person. After its injury or palsy, its functions can be either impaired or absent. Because of the presence of motor, sensory and parasympathetic fibers, the biology of its repair and function restoration depends on many factors. In order to achieve good outcome, many different therapies can be performed in order to restore as much of the nerve function as possible. When rehabilitation and physiotherapy are not sufficient, additional surgical procedures and therapies are taken into serious consideration. The final outcome of many of them is discussable, depending on nerve damage etiology. Stem cells in facial nerve repair are used, but long-term outcomes and results are still not fully known. In order to understand this therapeutic approach, clinicians and surgeons should understand the immunobiology of nerve repair and regeneration. In this review, potential stem cell usage in facial nerve regeneration procedures is discussed.

Tolerance of cranial nerves of the cavernous sinus to radiosurgery

International Nuclear Information System (INIS)

Tishler, R.B.; Loeffler, J.S.; Alexander, E. III; Kooy, H.M.; Lunsford, L.D.; Duma, C.; Flickinger, J.C.

1993-01-01

Stereotactic radiosurgery is becoming a more accepted treatment option for benign, deep seated intracranial lesions. However, little is known about the effects of large single fractions of radiation on cranial nerves. This study was undertaken to assess the effect of radiosurgery on the cranial nerves of the cavernous sinus. The authors examined the tolerance of cranial nerves (II-VI) following radiosurgery for 62 patients (42/62 with meningiomas) treated for lesions within or near the cavernous sinus. Twenty-nine patients were treated with a modified 6 MV linear accelerator (Joint Center for Radiation Therapy) and 33 were treated with the Gamma Knife (University of Pittsburgh). Three-dimensional treatment plans were retrospectively reviewed and maximum doses were calculated for the cavernous sinus and the optic nerve and chiasm. Median follow-up was 19 months (range 3-49). New cranial neuropathies developed in 12 patients from 3-41 months following radiosurgery. Four of these complications involved injury to the optic system and 8 (3/8 transient) were the result of injury to the sensory or motor nerves of the cavernous sinus. There was no clear relationship between the maximum dose to the cavernous sinus and the development of complications for cranial nerves III-VI over the dose range used (1000-4000 cGy). For the optic apparatus, there was a significantly increased incidence of complications with dose. Four of 17 patients (24%) receiving greater than 800 cGy to any part of the optic apparatus developed visual complications compared with 0/35 who received less than 800 cGy (p = 0.009). Radiosurgery using tumor-controlling doses of up to 4000 cGy appears to be a relatively safe technique in treating lesions within or near the sensory and motor nerves (III-VI) of the cavernous sinus. The dose to the optic apparatus should be limited to under 800 cGy. 21 refs., 4 tabs

Neurophysiological aspects of the trigeminal sensory system: an update.

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Van der Cruyssen, Frederic; Politis, Constantinus

2018-02-23

The trigeminal system is one of the most complex cranial nerve systems of the human body. Research on it has vastly grown in recent years and concentrated more and more on molecular mechanisms and pathophysiology, but thorough reviews on this topic are lacking, certainly on the normal physiology of the trigeminal sensory system. Here we review the current literature on neurophysiology of the trigeminal nerve from peripheral receptors up to its central projections toward the somatosensory cortex. We focus on the most recent scientific discoveries and describe historical relevant research to substantiate further. One chapter on new insights of the pathophysiology of pain at the level of the trigeminal system is added. A database search of Medline, Embase and Cochrane was conducted with the search terms 'animal study', 'neurophysiology', 'trigeminal', 'oral' and 'sensory'. Articles were manually selected after reading the abstract and where needed the article. Reference lists also served to include relevant research articles. Fifty-six articles were included after critical appraisal. Physiological aspects on mechanoreceptors, trigeminal afferents, trigeminal ganglion and central projections are reviewed in light of reference works. Embryologic and anatomic insights are cited where needed. A brief description of pathophysiology of pain pathways in the trigeminal area and recent advances in dental stem cell research are also discussed. Neurophysiology at the level of the central nervous system is not reviewed. The current body of knowledge is mainly based on animal and cadaveric studies, but recent advancements in functional imaging and molecular neuroscience are elucidating the pathways and functioning of this mixed nerve system. Extrapolation of animal studies or functioning of peripheral nerves should be warranted.

Platelet-rich plasma, an adjuvant biological therapy to assist peripheral nerve repair

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Mikel Sánchez

2017-01-01

Full Text Available Therapies such as direct tension-free microsurgical repair or transplantation of a nerve autograft, are nowadays used to treat traumatic peripheral nerve injuries (PNI, focused on the enhancement of the intrinsic regenerative potential of injured axons. However, these therapies fail to recreate the suitable cellular and molecular microenvironment of peripheral nerve repair and in some cases, the functional recovery of nerve injuries is incomplete. Thus, new biomedical engineering strategies based on tissue engineering approaches through molecular intervention and scaffolding offer promising outcomes on the field. In this sense, evidence is accumulating in both, preclinical and clinical settings, indicating that platelet-rich plasma products, and fibrin scaffold obtained from this technology, hold an important therapeutic potential as a neuroprotective, neurogenic and neuroinflammatory therapeutic modulator system, as well as enhancing the sensory and motor functional nerve muscle unit recovery.

Mobility-Related Consequences of Reduced Lower-Extremity Peripheral Nerve Function with Age

DEFF Research Database (Denmark)

Ward, Rachel E; Caserotti, P.; Cauley, Jane A

2016-01-01

-dwelling and institutionalized residents, 1 from a range of residential locations, and 1 of patients with peripheral arterial disease. Mean ages ranged from 71-82 years. Nerve function was assessed by vibration threshold (n=2); sensory measures and clinical signs and symptoms of neuropathy (n=2); motor nerve conduction (n=1......The objective of this study is to systematically review the relationship between lower-extremity peripheral nerve function and mobility in older adults. The National Library of Medicine (PubMed) was searched on March 23, 2015 with no limits on publication dates. One reviewer selected original...... research studies of older adults (>= 65 years) that assessed the relationship between lower-extremity peripheral nerve function and mobility-related outcomes. Participants, study design and methods of assessing peripheral nerve impairment were evaluated and results were reported and synthesized. Eight...

Task-dependent inhibition of slow-twitch soleus and excitation of fast-twitch gastrocnemius do not require high movement speed and velocity-dependent sensory feedback

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Ricky eMehta

2014-10-01

Full Text Available Although individual heads of triceps surae, soleus (SO and medial gastrocnemius (MG muscles, are often considered close functional synergists, previous studies have shown distinct activity patterns between them in some motor behaviors. The goal of this study was to test two hypotheses explaining inhibition of slow SO with respect to fast MG: (1 inhibition occurs at high movement velocities and mediated by velocity-dependent sensory feedback and (2 inhibition depends on the ankle-knee joint moment combination and does not require high movement velocities. The hypotheses were tested by comparing the SO EMG/MG EMG ratio during fast and slow motor behaviors (cat paw shake responses vs. back, straight leg load lifting in humans, which had the same ankle extension-knee flexion moment combination; and during fast and slow behaviors with the ankle extension-knee extension moment combination (human vertical jumping and stance phase of walking in cats and leg load lifting in humans. In addition, SO EMG/MG EMG ratio was determined during cat paw shake responses and walking before and after removal of stretch velocity-dependent sensory feedback by self-reinnervating SO and/or gastrocnemius. We found the ratio SO EMG/MG EMG below 1 (p<0.05 during fast paw shake responses and slow back load lifting, requiring the ankle extension-knee flexion moment combination; whereas the ratio SO EMG/MG EMG was above 1 (p<0.05 during fast vertical jumping and slow tasks of walking and leg load lifting, requiring ankle extension-knee extension moments. Removal of velocity-dependent sensory feedback did not affect the SO EMG/MG EMG ratio in cats. We concluded that the relative inhibition of SO does not require high muscle velocities, depends on ankle-knee moment combinations, and is mechanically advantageous for allowing a greater MG contribution to ankle extension and knee flexion moments.

Stimuli of sensory-motor nerves terminate arterial contractile effects of endothelin-1 by CGRP and dissociation of ET-1/ET(A)-receptor complexes

DEFF Research Database (Denmark)

Meens, Merlijn J P M T; Compeer, Matthijs G; Hackeng, Tilman M

2010-01-01

of the antagonists and (ii) can be selectively dissociated by an endogenous counterbalancing mechanism. METHODOLOGY/PRINCIPAL FINDINGS: In isolated rat mesenteric resistance arteries, ET(A)-antagonists, endothelium-derived relaxing factors and synthetic vasodilators transiently reduced contractile effects of ET-1......BACKGROUND: Endothelin-1 (ET-1), a long-acting paracrine mediator, is implicated in cardiovascular diseases but clinical trials with ET-receptor antagonists were not successful in some areas. We tested whether the quasi-irreversible receptor-binding of ET-1 (i) limits reversing effects...... but did not prevent persistent effects of the peptide. Stimuli of peri-vascular vasodilator sensory-motor nerves such as capsaicin not only reduced but also terminated long-lasting effects of ET-1. This was prevented by CGRP-receptor antagonists and was mimicked by exogenous calcitonin gene...

Encapsulated sensory corpuscle in the mucosa of human vocal cord: an electron microscope study.

Science.gov (United States)

Nagai, T

1982-05-01

Encapsulated sensory corpuscles of the Krause type were found in the mucosa of surgically removed human vocal cords. The corpuscles were ellipsoidal structures of about 30 to 50 micrometers and were located beneath the free edge in the mid-region along the intermembranous part. They contained a number of varicose nerve endings and lamellar cells. The lamellar cells had thin cytoplasmic lamellae which contained numerous cytoplasmic filaments and were interposed between the nerve endings. Attachment devices were frequently noted between the cytoplasmic lamellae and between the lamellae and nerve endings. Half-desmosomes were also noted along the plasma membrane of the lamellar cells. The intercellular space was filled with amorphous electron lucent material and contained a few collagen fibrils. Ladder-like filamentous structures were frequently encountered in the intercellular space. The location of the corpuscles at the free edge of the vocal cords suggests that the endings may receive the bilateral touch of the vibrating part of the cords in order to give sensory information for the control of the movement of the cords in phonation.

Infra Patellar Branch of Saphenous Nerve Injury during Hamstring Graft Harvest: Vertical versus Oblique Incisions.

Science.gov (United States)

Joshi, A; Kayasth, N; Shrestha, S; Kc, B R

2016-09-01

Autologous hamstring grafts are commonly used for anterior cruciate ligament reconstruction. The injury of infrapatellar branch of saphenous nerve is one of the concerns leading to various pattern of sensory loss in the operated leg. An oblique incision to harvest the graft has been reported to be better than the vertical one.The aim of this study was to compare the incidence, recovery of nerve injury and final outcome in patients with hamstring harvest of vertical or oblique incision. A total of 146 patients who underwent hamstring graft harvest for anterior cruciate ligament reconstruction, were included in the study. They were randomized into two (Vertical and Oblique) groups as per the incisions used. The sensory loss along the Infra Patellar Branch of Saphenous Nerve was documented on 3rd day. Recovery of the nerve injury was monitoredat three, six and 12 months follow-ups. At final follow up Tegner Lysholm score and scale was recorded to compare between two groups. The incidence of infrapatellar branch of saphenous nerve injury was 25% in vertical group and 16.36% in oblique group. Recovery of nerve injury started earlier in oblique group compared to vertical group. The mean TegnerLyshom score was not significantly different in both the groups. Oblique incision to harvest hamstring graft has lesser incidence of infrapatellar branch of saphenous nerve injury, recovers earlier and does not have any adverse effect on final outcome compared to the vertical incision.

Clinical, physiological and pathological characterisation of the sensory predominant peripheral neuropathy in copper deficiency.

Science.gov (United States)

Taylor, Sean W; Laughlin, Ruple S; Kumar, Neeraj; Goodman, Brent; Klein, Christopher J; Dyck, Peter J; Dyck, P James B

2017-10-01

Myelopathy is considered the most common neurological complication of copper deficiency. Concurrent peripheral neuropathy has been recognised in association with copper deficiency but has not been well characterised. To characterise the clinical, physiological and pathological features of copper-deficient peripheral neuropathy. Patients with simultaneous copper deficiency (peripheral neuropathy seen at the Mayo Clinic from 1985 to 2005 were identified. 34 patients were identified (median age 55 years, range 36-78) including 24 women and 10 men. Myelopathy was found in 21 patients. Median serum copper level was 0.11 μg/mL (range 0-0.58). The most frequent clinical and electrophysiological pattern of neuropathy was a sensory predominant length-dependent peripheral neuropathy (71%). Somatosensory evoked potentials demonstrated central slowing supporting myelopathy (96%). Quantitative sensory testing demonstrated both small and large fibre involvement (100%). Autonomic reflex screens (77%) and thermoregulatory sweat test (67%) confirmed sudomotor dysfunction. 14 cutaneous nerve biopsies revealed loss of myelinated nerve fibres (86%), increased regenerative clusters (50%), increased rates of axonal degeneration (91%) and increased numbers of empty nerve strands (73%). 71% of biopsies demonstrated epineurial perivascular inflammation. An axonal, length-dependent sensory predominant peripheral neuropathy causing sensory ataxia is characteristic of copper deficiency usually co-occurring with myelopathy. Neurophysiological testing confirms involvement of large, greater than small fibres. The pathological findings suggest axonal degeneration and repair. Inflammatory infiltrates are common but are small and of doubtful pathological significance. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Nerve fiber layer (NFL) degeneration associated with acute q-switched laser exposure in the nonhuman primate

Science.gov (United States)

Zwick, Harry; Zuclich, Joseph A.; Stuck, Bruce E.; Gagliano, Donald A.; Lund, David J.; Glickman, Randolph D.

1995-01-01

We have evaluated acute laser retinal exposure in non-human primates using a Rodenstock scanning laser ophthalmoscope (SLO) equipped with spectral imaging laser sources at 488, 514, 633, and 780 nm. Confocal spectral imaging at each laser wavelength allowed evaluation of the image plane from deep within the retinal vascular layer to the more superficial nerve fiber layer in the presence and absence of the short wavelength absorption of the macular pigment. SLO angiography included both fluorescein and indocyanine green procedures to assess the extent of damage to the sensory retina, the retinal pigment epithelium (RPE), and the choroidal vasculature. All laser exposures in this experiment were from a Q-switched Neodymium laser source at an exposure level sufficient to produce vitreous hemorrhage. Confocal imaging of the nerve fiber layer revealed discrete optic nerve sector defects between the lesion site and the macula (retrograde degeneration) as well as between the lesion site and the optic disk (Wallerian degeneration). In multiple hemorrhagic exposures, lesions placed progressively distant from the macula or overlapping the macula formed bridging scars visible at deep retinal levels. Angiography revealed blood flow disturbance at the retina as well as at the choroidal vascular level. These data suggest that acute parafoveal laser retinal injury can involve both direct full thickness damage to the sensory and non-sensory retina and remote nerve fiber degeneration. Such injury has serious functional implications for both central and peripheral visual function.

Afferent nerves regulating the cough reflex: Mechanisms and Mediators of Cough in Disease

Science.gov (United States)

Canning, Brendan J.

2010-01-01

Bronchopulmonary C-fibers and acid-sensitive, capsaicin-insensitive mechanoreceptors innervating the larynx, trachea and large bronchi regulate the cough reflex. These vagal afferent nerves may interact centrally with sensory input arising from afferent nerves innervating the intrapulmonary airways or even extrapulmonary afferents such as those innervating the nasal mucosa and esophagus to produce chronic cough or enhanced cough responsiveness. The mechanisms of cough initiation in health and in disease are briefly described. PMID:20172253

Insulin and IGF-II, but not IGF-I, stimulate the in vitro regeneration of adult frog sciatic sensory axons

DEFF Research Database (Denmark)

Edbladh, M; Svenningsen, Åsa Fex; Ekström, P A

1994-01-01

We used the in vitro regenerating frog sciatic nerve to look for effects of insulin and insulin-like growth factors I and II (IGF-I, IGF-II) on regeneration of sensory axons and on injury induced support cell proliferation in the outgrowth region. In nerves cultured for 11 days, a physiological...

Sensory determinants of the autonomous sensory meridian response (ASMR): understanding the triggers.

Science.gov (United States)

Barratt, Emma L; Spence, Charles; Davis, Nick J

2017-01-01

The autonomous sensory meridian response (ASMR) is an atypical sensory phenomenon involving electrostatic-like tingling sensations in response to certain sensory, primarily audio-visual, stimuli. The current study used an online questionnaire, completed by 130 people who self-reported experiencing ASMR. We aimed to extend preliminary investigations into the experience, and establish key multisensory factors contributing to the successful induction of ASMR through online media. Aspects such as timing and trigger load, atmosphere, and characteristics of ASMR content, ideal spatial distance from various types of stimuli, visual characteristics, context and use of ASMR triggers, and audio preferences are explored. Lower-pitched, complex sounds were found to be especially effective triggers, as were slow-paced, detail-focused videos. Conversely, background music inhibited the sensation for many respondents. These results will help in designing media for ASMR induction.

Sensory determinants of the autonomous sensory meridian response (ASMR: understanding the triggers

Directory of Open Access Journals (Sweden)

Emma L. Barratt

2017-10-01

Full Text Available The autonomous sensory meridian response (ASMR is an atypical sensory phenomenon involving electrostatic-like tingling sensations in response to certain sensory, primarily audio-visual, stimuli. The current study used an online questionnaire, completed by 130 people who self-reported experiencing ASMR. We aimed to extend preliminary investigations into the experience, and establish key multisensory factors contributing to the successful induction of ASMR through online media. Aspects such as timing and trigger load, atmosphere, and characteristics of ASMR content, ideal spatial distance from various types of stimuli, visual characteristics, context and use of ASMR triggers, and audio preferences are explored. Lower-pitched, complex sounds were found to be especially effective triggers, as were slow-paced, detail-focused videos. Conversely, background music inhibited the sensation for many respondents. These results will help in designing media for ASMR induction.

Complement inhibition accelerates regeneration in a model of peripheral nerve injury

NARCIS (Netherlands)

Ramaglia, Valeria; Tannemaat, Martijn Rudolf; de Kok, Maryla; Wolterman, Ruud; Vigar, Miriam Ann; King, Rosalind Helen Mary; Morgan, Bryan Paul; Baas, Frank

2009-01-01

Complement (C) activation is a crucial event in peripheral nerve degeneration but its effect on the subsequent regeneration is unknown. Here we show that genetic deficiency of the sixth C component, C6, accelerates axonal regeneration and recovery in a rat model of sciatic nerve injury. Foot-flick

Neuropathic pain: is quantitative sensory testing helpful?

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Krumova, Elena K; Geber, Christian; Westermann, Andrea; Maier, Christoph

2012-08-01

Neuropathic pain arises as a consequence of a lesion or disease affecting the somatosensory system and is characterised by a combination of positive and negative sensory symptoms. Quantitative sensory testing (QST) examines the sensory perception after application of different mechanical and thermal stimuli of controlled intensity and the function of both large (A-beta) and small (A-delta and C) nerve fibres, including the corresponding central pathways. QST can be used to determine detection, pain thresholds and stimulus-response curves and can thus detect both negative and positive sensory signs, the second ones not being assessed by other methods. Similarly to all other psychophysical tests QST requires standardised examination, instructions and data evaluation to receive valid and reliable results. Since normative data are available, QST can contribute also to the individual diagnosis of neuropathy, especially in the case of isolated small-fibre neuropathy, in contrast to the conventional electrophysiology which assesses only large myelinated fibres. For example, detection of early stages of subclinical neuropathy in symptomatic or asymptomatic patients with diabetes mellitus can be helpful to optimise treatment and identify diabetic foot at risk of ulceration. QST assessed the individual's sensory profile and thus can be valuable to evaluate the underlying pain mechanisms which occur in different frequencies even in the same neuropathic pain syndromes. Furthermore, assessing the exact sensory phenotype by QST might be useful in the future to identify responders to certain treatments in accordance to the underlying pain mechanisms.

Development of regenerative peripheral nerve interfaces for motor control of neuroprosthetic devices

Science.gov (United States)

Kemp, Stephen W. P.; Urbanchek, Melanie G.; Irwin, Zachary T.; Chestek, Cynthia A.; Cederna, Paul S.

2017-05-01

Traumatic peripheral nerve injuries suffered during amputation commonly results in debilitating neuropathic pain in the affected limb. Modern prosthetic technologies allow for intuitive, simultaneous control of multiple degrees of freedom. However, these state-of-the-art devices require separate, independent control signals for each degree of freedom, which is currently not possible. As a result, amputees reject up to 75% of myoelectric devices preferring instead to use body-powered artificial limbs which offer subtle sensory feedback. Without meaningful and intuitive sensory feedback, even the most advanced myoelectric prostheses remain insensate, burdensome, and are associated with enormous cognitive demand and mental fatigue. The ideal prosthetic device is one which is capable of providing intuitive somatosensory feedback essential for interaction with the environment. Critical to the design of such a bioprosthetic device is the development of a reliable biologic interface between human and machine. This ideal patient-prosthetic interface allows for transmission of both afferent somatosensory information and efferent motor signals for a closed-loop feedback system of neural control. Our lab has developed the Regenerative Peripheral Nerve Interface (RPNI) as a biologic nerve interface designed for stable integration of a prosthetic device with transected peripheral nerves in a residual limb. The RPNI is constructed by surgically implanting the distal end of a transected peripheral nerve into an autogenous muscle graft. Animal experiments in our lab have shown recording of motor signals from RPNI's implanted into both rodents and monkeys. Here, we achieve high amplitude EMG signals with a high signal to noise (SNR) ratio.

An inversion disrupting FAM134B is associated with sensory neuropathy in the Border Collie dog breed

OpenAIRE

Forman, Oliver P.; Hitti, Rebekkah J.; Pettitt, Louise; Jenkins, Christopher A.; O'Brien, Dennis P.; Shelton, G. Diane; De Risio, Luisa; Gutierrez Quintana, Rodrigo; Beltran, Elsa; Mellersh, Cathryn

2016-01-01

Sensory neuropathy in the Border Collie is a severe neurological disorder caused by the degeneration of sensory and, to a lesser extent, motor nerve cells with clinical signs starting between 2 and 7 months of age. Using a genome-wide association study approach with three cases and 170 breed matched controls, a suggestive locus for sensory neuropathy was identified that was followed up using a genome sequencing approach. An inversion disrupting the candidate gene FAM134B was identified. Genot...

Cross-Excitation in Peripheral Sensory Ganglia Associated with Pain Transmission

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Katsuhiro Omoto

2015-08-01

Full Text Available Despite the absence of synaptic contacts, cross-excitation of neurons in sensory ganglia during signal transmission is considered to be chemically mediated and appears increased in chronic pain states. In this study, we modulated neurotransmitter release in sensory neurons by direct application of type A botulinum neurotoxin (BoNT/A to sensory ganglia in an animal model of neuropathic pain and evaluated the effect of this treatment on nocifensive. Unilateral sciatic nerve entrapment (SNE reduced the ipsilateral hindpaw withdrawal threshold to mechanical stimulation and reduced hindpaw withdrawal latency to thermal stimulation. Direct application of BoNT/A to the ipsilateral L4 dorsal root ganglion (DRG was localized in the cell bodies of the DRG and reversed the SNE-induced decreases in withdrawal thresholds within 2 days of BoNT/A administration. Results from this study suggest that neurotransmitter release within sensory ganglia is involved in the regulation of pain-related signal transmission.

Use of Processed Nerve Allografts to Repair Nerve Injuries Greater Than 25 mm in the Hand.

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Rinker, Brian; Zoldos, Jozef; Weber, Renata V; Ko, Jason; Thayer, Wesley; Greenberg, Jeffrey; Leversedge, Fraser J; Safa, Bauback; Buncke, Gregory

2017-06-01

Processed nerve allografts (PNAs) have been demonstrated to have improved clinical results compared with hollow conduits for reconstruction of digital nerve gaps less than 25 mm; however, the use of PNAs for longer gaps warrants further clinical investigation. Long nerve gaps have been traditionally hard to study because of low incidence. The advent of the RANGER registry, a large, institutional review board-approved, active database for PNA (Avance Nerve Graft; AxoGen, Inc, Alachua, FL) has allowed evaluation of lower incidence subsets. The RANGER database was queried for digital nerve repairs of 25 mm or greater. Demographics, injury, treatment, and functional outcomes were recorded on standardized forms. Patients younger than 18 and those lacking quantitative follow-up data were excluded. Recovery was graded according to the Medical Research Council Classification for sensory function, with meaningful recovery defined as S3 or greater level. Fifty digital nerve injuries in 28 subjects were included. There were 22 male and 6 female subjects, and the mean age was 45. Three patients gave a previous history of diabetes, and there were 6 active smokers. The most commonly reported mechanisms of injury were saw injuries (n = 13), crushing injuries (n = 9), resection of neuroma (n = 9), amputation/avulsions (n = 8), sharp lacerations (n = 7), and blast/gunshots (n = 4). The average gap length was 35 ± 8 mm (range, 25-50 mm). Recovery to the S3 or greater level was reported in 86% of repairs. Static 2-point discrimination (s2PD) and Semmes-Weinstein monofilament (SWF) were the most common completed assessments. Mean s2PD in 24 repairs reporting 2PD data was 9 ± 4 mm. For the 38 repairs with SWF data, protective sensation was reported in 33 repairs, deep pressure in 2, and no recovery in 3. These data compared favorably with historical data for nerve autograft repairs, with reported levels of meaningful recovery of 60% to 88%. There were no reported adverse effects

An electron microscopic study of intraepithelial nerves of oral mucosa of rats during aging

International Nuclear Information System (INIS)

Choi, Dai Ho; You, Dong Soo

1984-01-01

Observation made in this study bring home salient features that may contribute towards a better understanding of the relationship between the available physiologic data and anatomical characteristics of those nerve fibers that penetrate into the intraepithelial space in the oral cavity. The present investigation characterized the fine structure of nerve fibers in oral mucosae with respect to the manner in which presumed sensory fibers enter into the intraepithelial space by penetration of the basal lamina. The conclusions were made little discernible qualitative difference exists between young and old animals, concerning the fine structural characteristics of nerve fibers and nerve endings and in old animals, significant reductions exist in the number of neural elements in the intraepithelial space.

Assessment of paclitaxel induced sensory polyneuropathy with "Catwalk" automated gait analysis in mice.

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Petra Huehnchen

Full Text Available Neuropathic pain as a symptom of sensory nerve damage is a frequent side effect of chemotherapy. The most common behavioral observation in animal models of chemotherapy induced polyneuropathy is the development of mechanical allodynia, which is quantified with von Frey filaments. The data from one study, however, cannot be easily compared with other studies owing to influences of environmental factors, inter-rater variability and differences in test paradigms. To overcome these limitations, automated quantitative gait analysis was proposed as an alternative, but its usefulness for assessing animals suffering from polyneuropathy has remained unclear. In the present study, we used a novel mouse model of paclitaxel induced polyneuropathy to compare results from electrophysiology and the von Frey method to gait alterations measured with the Catwalk test. To mimic recently improved clinical treatment strategies of gynecological malignancies, we established a mouse model of dose-dense paclitaxel therapy on the common C57Bl/6 background. In this model paclitaxel treated animals developed mechanical allodynia as well as reduced caudal sensory nerve action potential amplitudes indicative of a sensory polyneuropathy. Gait analysis with the Catwalk method detected distinct alterations of gait parameters in animals suffering from sensory neuropathy, revealing a minimized contact of the hind paws with the floor. Treatment of mechanical allodynia with gabapentin improved altered dynamic gait parameters. This study establishes a novel mouse model for investigating the side effects of dose-dense paclitaxel therapy and underlines the usefulness of automated gait analysis as an additional easy-to-use objective test for evaluating painful sensory polyneuropathy.

Acetylcholinesterase inhibition and locomotor function after motor-sensory cortex impact injury.

Science.gov (United States)

Holschneider, Daniel P; Guo, Yumei; Roch, Margareth; Norman, Keith M; Scremin, Oscar U

2011-09-01

Traumatic brain injury (TBI) induces transient or persistent dysfunction of gait and balance. Enhancement of cholinergic transmission has been reported to accelerate recovery of cognitive function after TBI, but the effects of this intervention on locomotor activity remain largely unexplored. The hypothesis that enhancement of cholinergic function by inhibition of acetylcholinesterase (AChE) improves locomotion following TBI was tested in Sprague-Dawley male rats after a unilateral controlled cortical impact (CCI) injury of the motor-sensory cortex. Locomotion was tested by time to fall on the constant speed and accelerating Rotarod, placement errors and time to cross while walking through a horizontal ladder, activity monitoring in the home cages, and rearing behavior. Assessments were performed the 1st and 2nd day and the 1st, 2nd, and 3rd week after TBI. The AChE inhibitor physostigmine hemisulfate (PHY) was administered continuously via osmotic minipumps implanted subcutaneously at the rates of 1.6-12.8 μmol/kg/day. All measures of locomotion were impaired by TBI and recovered to initial levels between 1 and 3 weeks post-TBI, with the exception of the maximum speed achievable on the accelerating Rotarod, as well as rearing in the open field. PHY improved performance in the accelerating Rotarod at 1.6 and 3.2 μmol/kg/day (AChE activity 95 and 78% of control, respectively), however, higher doses induced progressive deterioration. No effect or worsening of outcomes was observed at all PHY doses for home cage activity, rearing, and horizontal ladder walking. Potential benefits of cholinesterase inhibition on locomotor function have to be weighed against the evidence of the narrow range of useful doses.

Sensory modulation disorders in childhood epilepsy.

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van Campen, Jolien S; Jansen, Floor E; Kleinrensink, Nienke J; Joëls, Marian; Braun, Kees Pj; Bruining, Hilgo

2015-01-01

Altered sensory sensitivity is generally linked to seizure-susceptibility in childhood epilepsy but may also be associated to the highly prevalent problems in behavioral adaptation. This association is further suggested by the frequent overlap of childhood epilepsy with autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD), conditions in which altered behavioral responses to sensory stimuli have been firmly established. A continuum of sensory processing defects due to imbalanced neuronal inhibition and excitation across these disorders has been hypothesizedthat may lead to common symptoms of inadequate modulation of behavioral responses to sensory stimuli. Here, we investigated the prevalence of sensory modulation disorders among children with epilepsy and their relation with symptomatology of neurodevelopmental disorders. We used the Sensory Profile questionnaire to assess behavioral responses to sensory stimuli and categorize sensory modulation disorders in children with active epilepsy (aged 4-17 years). We related these outcomes to epilepsy characteristics and tested their association with comorbid symptoms of ASD (Social Responsiveness Scale) and ADHD (Strengths and Difficulties Questionnaire). Sensory modulation disorders were reported in 49 % of the 158 children. Children with epilepsy reported increased behavioral responses associated with sensory "sensitivity," "sensory avoidance," and "poor registration" but not "sensory seeking." Comorbidity of ASD and ADHD was associated with more severe sensory modulation problems, although 27 % of typically developing children with epilepsy also reported a sensory modulation disorder. Sensory modulation disorders are an under-recognized problem in children with epilepsy. The extent of the modulation difficulties indicates a substantial burden on daily functioning and may explain an important part of the behavioral distress associated with childhood epilepsy.

Modulation of sensory inhibition of motor evoked potentials elicited by TMS prior to movement?

DEFF Research Database (Denmark)

Leukel, Christian; Lundbye-Jensen, Jesper; Nielsen, Jens Bo

because the afferent information triggered the movement and therefore was important for motor performance. Alle et al. (2009). J Physiol 587:5163-5176 Chen et al. (1998). Ann Neurol 44:317-325 Tokimura et al. (2000). J Physiol 523 Pt 2:503-513......Short latency afferent inhibition (SAI) refers to a decrement of the size of a motor evoked potential (MEP) by transcranial magnetic stimulation (TMS) after electrical stimulation of a peripheral afferent nerve (PNS) (Tokimura et al. 2000). Since SAI occurs when TMS is applied at the time...... of corticospinal cells to TMS, which starts approximately 100 ms prior to the onset of movement (Chen et al. 1998). Thus, it is hypothesized that the modulation of the MEP prior to movement is linked to the afferent volley arriving at the sensorimotor cortex. It might be speculated that the MEP was facilitated...

Sensory cortical re-mapping following upper-limb amputation and subsequent targeted reinnervation: A case report

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Jun Yao

2015-01-01

Full Text Available This case study demonstrates the change of sensory cortical representations of the residual parts of the arm in an individual who underwent a trans-humeral amputation and subsequent targeted reinnervation (TR. As a relatively new surgical technique, TR restores a direct neural connection from amputated sensorimotor nerves to specific target muscles. This method has been successfully applied to upper-limb and lower-limb amputees, and has shown effectiveness in regaining control signals via the newly re-innervated muscles. Correspondingly, recent study results have shown that motor representations for the missing limb move closer to their original locations following TR. Besides regaining motor control signals, TR also restores the sensation in the re-innervated skin areas. We therefore hypothesize that TR causes analogous cortical sensory remapping that may return closer to their original locations. In order to test this hypothesis, cortical activity in response to sensory-level electrical stimulation in different parts of the arm was studied longitudinally in one amputated individual before and up to 2 years after TR. Our results showed that 1 before TR, the cortical response to sensory electrical stimulation in the residual limb showed a diffuse bilateral pattern without a clear focus in either the time or spatial domain; and 2 2 years after TR, the sensory map of the reinnervated median nerve reorganized, showing predominant activity over the contralateral S1 hand area as well as moderate activity over the ipsilateral S1. Therefore, this work provides new evidence for long-term sensory cortical plasticity in the human brain after TR.

Sensory cortical re-mapping following upper-limb amputation and subsequent targeted reinnervation: A case report.

Science.gov (United States)

Yao, Jun; Chen, Albert; Kuiken, Todd; Carmona, Carolina; Dewald, Julius

2015-01-01

This case study demonstrates the change of sensory cortical representations of the residual parts of the arm in an individual who underwent a trans-humeral amputation and subsequent targeted reinnervation (TR). As a relatively new surgical technique, TR restores a direct neural connection from amputated sensorimotor nerves to specific target muscles. This method has been successfully applied to upper-limb and lower-limb amputees, and has shown effectiveness in regaining control signals via the newly re-innervated muscles. Correspondingly, recent study results have shown that motor representations for the missing limb move closer to their original locations following TR. Besides regaining motor control signals, TR also restores the sensation in the re-innervated skin areas. We therefore hypothesize that TR causes analogous cortical sensory remapping that may return closer to their original locations. In order to test this hypothesis, cortical activity in response to sensory-level electrical stimulation in different parts of the arm was studied longitudinally in one amputated individual before and up to 2 years after TR. Our results showed that 1) before TR, the cortical response to sensory electrical stimulation in the residual limb showed a diffuse bilateral pattern without a clear focus in either the time or spatial domain; and 2) 2 years after TR, the sensory map of the reinnervated median nerve reorganized, showing predominant activity over the contralateral S1 hand area as well as moderate activity over the ipsilateral S1. Therefore, this work provides new evidence for long-term sensory cortical plasticity in the human brain after TR.

Reversible acute axonal polyneuropathy associated with Wernicke-Korsakoff syndrome: impaired physiological nerve conduction due to thiamine deficiency?

Science.gov (United States)

Ishibashi, S; Yokota, T; Shiojiri, T; Matunaga, T; Tanaka, H; Nishina, K; Hirota, H; Inaba, A; Yamada, M; Kanda, T; Mizusawa, H

2003-05-01

Acute axonal polyneuropathy and Wernicke-Korsakoff encephalopathy developed simultaneously in three patients. Nerve conduction studies (NCS) detected markedly decreased compound muscle action potentials (CMAPs) and sensory nerve action potentials (SNAPs) with minimal conduction slowing; sympathetic skin responses (SSRs) were also notably decreased. Sural nerve biopsies showed only mild axonal degeneration with scattered myelin ovoid formation. The symptoms of neuropathy lessened within two weeks after an intravenous thiamine infusion. CMAPs, SNAPs, and SSRs also increased considerably. We suggest that this is a new type of peripheral nerve impairment: physiological conduction failure with minimal conduction delay due to thiamine deficiency.

Thy1.2 YFP-16 transgenic mouse labels a subset of large-diameter sensory neurons that lack TRPV1 expression.

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Thomas E Taylor-Clark

Full Text Available The Thy1.2 YFP-16 mouse expresses yellow fluorescent protein (YFP in specific subsets of peripheral and central neurons. The original characterization of this model suggested that YFP was expressed in all sensory neurons, and this model has been subsequently used to study sensory nerve structure and function. Here, we have characterized the expression of YFP in the sensory ganglia (DRG, trigeminal and vagal of the Thy1.2 YFP-16 mouse, using biochemical, functional and anatomical analyses. Despite previous reports, we found that YFP was only expressed in approximately half of DRG and trigeminal neurons and less than 10% of vagal neurons. YFP-expression was only found in medium and large-diameter neurons that expressed neurofilament but not TRPV1. YFP-expressing neurons failed to respond to selective agonists for TRPV1, P2X(2/3 and TRPM8 channels in Ca2+ imaging assays. Confocal analysis of glabrous skin, hairy skin of the back and ear and skeletal muscle indicated that YFP was expressed in some peripheral terminals with structures consistent with their presumed non-nociceptive nature. In summary, the Thy1.2 YFP-16 mouse expresses robust YFP expression in only a subset of sensory neurons. But this mouse model is not suitable for the study of nociceptive nerves or the function of such nerves in pain and neuropathies.

A comparison between complete immobilisation and protected active mobilisation in sensory nerve recovery following isolated digital nerve injury.

LENUS (Irish Health Repository)

Henry, F P

2012-06-01

Post-operative immobilisation following isolated digital nerve repair remains a controversial issue amongst the microsurgical community. Protocols differ from unit to unit and even, as evidenced in our unit, may differ from consultant to consultant. We undertook a retrospective review of 46 patients who underwent isolated digital nerve repair over a 6-month period. Follow-up ranged from 6 to 18 months. Twenty-four were managed with protected active mobilisation over a 4-week period while 22 were immobilised over the same period. Outcomes such as return to work, cold intolerance, two-point discrimination and temperature differentiation were used as indicators of clinical recovery. Our results showed that there was no significant difference noted in either clinical assessment of recovery or return to work following either post-operative protocol, suggesting that either regime may be adopted, tailored to the patient\\'s needs and resources of the unit.

Biofabrication and testing of a fully cellular nerve graft

International Nuclear Information System (INIS)

Owens, Christopher M; Marga, Francoise; Forgacs, Gabor; Heesch, Cheryl M

2013-01-01

Rupture of a nerve is a debilitating injury with devastating consequences for the individual's quality of life. The gold standard of repair is the use of an autologous graft to bridge the severed nerve ends. Such repair however involves risks due to secondary surgery at the donor site and may result in morbidity and infection. Thus the clinical approach to repair often involves non-cellular solutions, grafts composed of synthetic or natural materials. Here we report on a novel approach to biofabricate fully biological grafts composed exclusively of cells and cell secreted material. To reproducibly and reliably build such grafts of composite geometry we use bioprinting. We test our grafts in a rat sciatic nerve injury model for both motor and sensory function. In particular we compare the regenerative capacity of the biofabricated grafts with that of autologous grafts and grafts made of hollow collagen tubes by measuring the compound action potential (for motor function) and the change in mean arterial blood pressure as consequence of electrically eliciting the somatic pressor reflex. Our results provide evidence that bioprinting is a promising approach to nerve graft fabrication and as a consequence to nerve regeneration. (paper)

The L1-type cell adhesion molecule Neuroglian is necessary for maintenance of sensory axon advance in the Drosophila embryo

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Martin Veronica

2008-04-01

Full Text Available Abstract Background Cell adhesion molecules have long been implicated in the regulation of axon growth, but the precise cellular roles played by individual cell adhesion molecules and the molecular basis for their action are still not well understood. We have used the sensory system of the Drosophila embryo to shed light on the mechanism by which the L1-type cell adhesion molecule Neuroglian regulates axon growth. Results We have found a highly penetrant sensory axon stalling phenotype in neuroglian mutant embryos. Axons stalled at a variety of positions along their normal trajectory, but most commonly in the periphery some distance along the peripheral nerve. All lateral and dorsal cluster sensory neurons examined, except for the dorsal cluster neuron dbd, showed stalling. Sensory axons were never seen to project along inappropriate pathways in neuroglian mutants and stalled axons showed normal patterns of fasciculation within nerves. The growth cones of stalled axons possessed a simple morphology, similar to their appearance in wild-type embryos when advancing along nerves. Driving expression of the wild-type form of Neuroglian in sensory neurons alone rescued the neuroglian mutant phenotype of both pioneering and follower neurons. A partial rescue was achieved by expressing the Neuroglian extracellular domain. Over/mis-expression of Neuroglian in all neurons, oenocytes or trachea had no apparent effect on sensory axon growth. Conclusion We conclude that Neuroglian is necessary to maintain axon advance along axonal substrates, but is not required for initiation of axon outgrowth, axon fasciculation or recognition of correct growth substrates. Expression of Neuroglian in sensory neurons alone is sufficient to promote axon advance and the intracellular region of the molecule is largely dispensable for this function. It is unlikely, therefore, that Nrg acts as a molecular 'clutch' to couple adhesion of F-actin within the growth cone to the

Electrical nerve stimulation as an aid to the placement of a brachial plexus block : clinical communication

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K.E. Joubert

2002-07-01

Full Text Available Most local anaesthetic blocks are placed blindly, based on a sound knowledge of anatomy. Very often the relationship between the site of deposition of local anaesthetic and the nerve to be blocked is unknown. Large motor neurons may be stimulated with the aid of an electrical current. By observing for muscle twitches, through electrical stimulation of the nerve, a needle can be positioned extremely close to the nerve. The accuracy of local anaesthetic blocks can be improved by this technique. By using the lowest possible current a needle could be positioned within 2-5mm of a nerve. The correct duration of stimulation ensures that stimulation of sensory nerves does not occur. The use of electrical nerve stimulation in veterinary medicine is a novel technique that requires further evaluation.

Effect of walking and resting after three cryotherapy modalities on the recovery of sensory and motor nerve conduction velocity in healthy subjects Efeito da marcha e do repouso após aplicação de três protocolos de crioterapia na recuperação da velocidade de condução sensorial e motora em sujeitos saudáveis

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Esperanza Herrera

2011-06-01

Full Text Available BACKGROUND: Different cryotherapy modalities have distinct effects on sensory and motor nerve conduction parameters. However, it is unclear how these parameters change during the post-cooling period and how the exercise carried out in this period would influence the recovery of nerve conduction velocity (NCV. OBJECTIVES: To compare the effects of three cryotherapy modalities on post-cooling NCV and to analyze the effect of walking on the recovery of sensory and motor NCV. METHODS: Thirty six healthy young subjects were randomly allocated into three groups: ice massage (n=12, ice pack (n=12 and cold water immersion (n=12. The modalities were applied to the right leg. The subjects of each modality group were again randomized to perform a post-cooling activity: a 30min rest, b walking 15 min followed by 15 min rest. The NCV of sural (sensory and posterior tibial (motor nerves was evaluated. Initial (pre-cooling and final (30 min post-cooling NCV were compared using a paired t-test. The effects of the modalities and the post-cooling activities on NCV were evaluated by an analysis of covariance. The significance level was α=0.05. RESULTS: There was a significant difference between immersion and ice massage on final sensory NCV (p=0.009. Ice pack and ice massage showed similar effects (p>0.05. Walking accelerated the recovery of sensory and motor NCV, regardless of the modality previously applied (pCONTEXTUALIZAÇÃO: Diferentes protocolos de crioterapia têm ação distinta nos parâmetros de condução neural sensorial e motora. No entanto, não se sabe como é o comportamento desses parâmetros no período pós-resfriamento e como o exercício físico realizado nesse período atuaria na recuperação da velocidade de condução nervosa (VCN. OBJETIVOS: Comparar o efeito de três protocolos de crioterapia na VCN pós-resfriamento e analisar o efeito da marcha pós-resfriamento na recuperação da VCN sensorial e motora. MÉTODOS: Trinta e seis

Immunoglobulin deposits in peripheral nerve endings detected by skin biopsy in patients with IgM M proteins and neuropathy

DEFF Research Database (Denmark)

Jønsson, V; Jensen, T S; Friis, M L

1987-01-01

biopsies provide a simple effective method of detecting immunoglobulin binding to peripheral nerves in patients suspected of having an autoimmune neuropathy. In contrast to sural nerve biopsy, skin biopsy does not cause sensory loss or pain in a denervated area and can easily be repeated.......Immunofluorescence studies of sural nerve and skin biopsies from three patients with IgM M proteins and clinical neuropathy showed that IgM M protein was bound to the nerve myelin in two patients and by the peri- and endoneurium in one. It is suggested that immunohistochemical studies of skin...

Neurological complications in thyroid surgery: a surgical point of view on laryngeal nerves.

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EMANUELA eVARALDO

2014-07-01

Full Text Available The cervical branches of the vagus nerve that are pertinent to endocrine surgery are the superior and the inferior laryngeal nerves: their anatomical course in the neck places them at risk during thyroid surgery. The external branch of the superior laryngeal nerve (EB is at risk during thyroid surgery because of its close anatomical relationship with the superior thyroid vessels and the superior thyroid pole region. The rate of EB injury (which leads to the paralysis of the cricothyroid muscle varies from 0 to 58%. The identification of the EB during surgery helps avoiding both an accidental transection and an excessive stretching. When the nerve is not identified,the ligation of superior thyroid artery branches close to the thyroid gland is suggested, as well as the abstention from an indiscriminate use of energy-based devices that might damage it. The inferior laryngeal nerve (RLN runs in the tracheoesophageal groove toward the larynx, close to the posterior aspect of the thyroid. It is the main motor nerve of the intrinsic laryngeal muscles, and also provides sensory innervation to the larynx. Its injury finally causes the paralysis of the omolateral vocal cord and various sensory alterations: the symptoms range from mild to severe hoarseness, to acute airway obstruction and swallowing impairment. Permanent lesions of the RNL occur from 0.3 to 7% of cases, according to different factors. The surgeon must be aware of the possible anatomical variations of the nerve which should be actively searched for and identified. Visual control and gentle dissection of RLN are imperative. The use of intraoperative nerve monitoring has been safely applied but, at the moment, its impact in the incidence of RLN injuries has not been clarified. In conclusion, despite a thorough surgical technique and the use of intraoperative neuromonitoring, the incidence of neurological complications after thyroid surgery cannot be suppressed, but should be maintained in a

Non-invasive stimulation of the vibrissal pad improves recovery of whisking function after simultaneous lesion of the facial and infraorbital nerves in rats.

Science.gov (United States)

Bendella, H; Pavlov, S P; Grosheva, M; Irintchev, A; Angelova, S K; Merkel, D; Sinis, N; Kaidoglou, K; Skouras, E; Dunlop, S A; Angelov, Doychin N

2011-07-01

We have recently shown that manual stimulation of target muscles promotes functional recovery after transection and surgical repair to pure motor nerves (facial: whisking and blink reflex; hypoglossal: tongue position). However, following facial nerve repair, manual stimulation is detrimental if sensory afferent input is eliminated by, e.g., infraorbital nerve extirpation. To further understand the interplay between sensory input and motor recovery, we performed simultaneous cut-and-suture lesions on both the facial and the infraorbital nerves and examined whether stimulation of the sensory afferents from the vibrissae by a forced use would improve motor recovery. The efficacy of 3 treatment paradigms was assessed: removal of the contralateral vibrissae to ensure a maximal use of the ipsilateral ones (vibrissal stimulation; Group 2), manual stimulation of the ipsilateral vibrissal muscles (Group 3), and vibrissal stimulation followed by manual stimulation (Group 4). Data were compared to controls which underwent surgery but did not receive any treatment (Group 1). Four months after surgery, all three treatments significantly improved the amplitude of vibrissal whisking to 30° versus 11° in the controls of Group 1. The three treatments also reduced the degree of polyneuronal innervation of target muscle fibers to 37% versus 58% in Group 1. These findings indicate that forced vibrissal use and manual stimulation, either alone or sequentially, reduce target muscle polyinnervation and improve recovery of whisking function when both the sensory and the motor components of the trigemino-facial system regenerate.

Radiation impairs perineural invasion by modulating the nerve microenvironment.

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Richard L Bakst

Full Text Available Perineural invasion (PNI by cancer cells is an ominous clinical event that is associated with increased local recurrence and poor prognosis. Although radiation therapy (RT may be delivered along the course of an invaded nerve, the mechanisms through which radiation may potentially control PNI remain undefined.An in vitro co-culture system of dorsal root ganglia (DRG and pancreatic cancer cells was used as a model of PNI. An in vivo murine sciatic nerve model was used to study how RT to nerve or cancer affects nerve invasion by cancer.Cancer cell invasion of the DRG was partially dependent on DRG secretion of glial-derived neurotrophic factor (GDNF. A single 4 Gy dose of radiation to the DRG alone, cultured with non-radiated cancer cells, significantly inhibited PNI and was associated with decreased GDNF secretion but intact DRG viability. Radiation of cancer cells alone, co-cultured with non-radiated nerves, inhibited PNI through predominantly compromised cancer cell viability. In a murine model of PNI, a single 8 Gy dose of radiation to the sciatic nerve prior to implantation of non-radiated cancer cells resulted in decreased GDNF expression, decreased PNI by imaging and histology, and preservation of sciatic nerve motor function.Radiation may impair PNI through not only direct effects on cancer cell viability, but also an independent interruption of paracrine mechanisms underlying PNI. RT modulation of the nerve microenvironment may decrease PNI, and hold significant therapeutic implications for RT dosing and field design for patients with cancers exhibiting PNI.

Acid solution is a suitable medium for introducing QX-314 into nociceptors through TRPV1 channels to produce sensory-specific analgesic effects.

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He Liu

Full Text Available BACKGROUND: Previous studies have demonstrated that QX-314, an intracellular sodium channel blocker, can enter into nociceptors through capsaicin-activated TRPV1 or permeation of the membrane by chemical enhancers to produce a sensory-selective blockade. However, the obvious side effects of these combinations limit the application of QX-314. A new strategy for targeting delivery of QX-314 into nociceptors needs further investigation. The aim of this study is to test whether acidic QX-314, when dissolves in acidic solution directly, can enter into nociceptors through acid-activated TRPV1 and block sodium channels from the intracellular side to produce a sensory-specific analgesic effect. METHODOLOGY/PRINCIPAL FINDINGS: Acidic solution or noradrenaline was injected intraplantarly to induce acute pain behavior in mice. A chronic constrictive injury model was performed to induce chronic neuropathic pain. A sciatic nerve blockade model was used to evaluate the sensory-specific analgesic effects of acidic QX-314. Thermal and mechanical hyperalgesia were measured by using radiant heat and electronic von Frey filaments test. Spinal Fos protein expression was determined by immunohistochemistry. The expression of p-ERK was detected by western blot assay. Whole cell clamp recording was performed to measure action potentials and total sodium current in rats DRG neurons. We found that pH 5.0 PBS solution induced behavioral hyperalgesia accompanied with the increased expression of spinal Fos protein and p-ERK. Pretreatment with pH 5.0 QX-314, and not pH 7.4 QX-314, alleviated pain behavior, inhibited the increased spinal Fos protein and p-ERK expression induced by pH 5.0 PBS or norepinephrine, blocked sodium currents and abolished the production of action potentials evoked by current injection. The above effects were prevented by TRPV1 channel inhibitor SB366791, but not by ASIC channel inhibitor amiloride. Furthermore, acidic QX-314 employed adjacent to the

Hemifacial Pain and Hemisensory Disturbance Referred from Occipital Neuralgia Caused by Pathological Vascular Contact of the Greater Occipital Nerve.

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Son, Byung-Chul; Choi, Jin-Gyu

2017-01-01

Here we report a unique case of chronic occipital neuralgia caused by pathological vascular contact of the left greater occipital nerve. After 12 months of left-sided, unremitting occipital neuralgia, a hypesthesia and facial pain developed in the left hemiface. The decompression of the left greater occipital nerve from pathological contacts with the occipital artery resulted in immediate relief for hemifacial sensory change and facial pain, as well as chronic occipital neuralgia. Although referral of pain from the stimulation of occipital and cervical structures innervated by upper cervical nerves to the frontal head of V1 trigeminal distribution has been reported, the development of hemifacial sensory change associated with referred trigeminal pain from chronic occipital neuralgia is extremely rare. Chronic continuous and strong afferent input of occipital neuralgia caused by pathological vascular contact with the greater occipital nerve seemed to be associated with sensitization and hypersensitivity of the second-order neurons in the trigeminocervical complex, a population of neurons in the C2 dorsal horn characterized by receiving convergent input from dural and cervical structures.

Gallic acid and exercise training improve motor function, nerve conduction velocity but not pain sense reflex after experimental sciatic nerve crush in male rats

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Maryam Hajimoradi

2015-06-01

Full Text Available Objective: The aim of present study was to evaluate the effects of oral administration of gallic acid (GA for 21 days alone and in combination with exercise on nerve conduction velocity and sensory and motor functions in rats with sciatic nerve crush. Materials and Methods: Seventy adult male Wistar rats (250-300 g were divided randomly into 7 groups with 10 in each: 1 Control (Cont, 2 Crushed + Vehicle (Cr +Veh, 3-5 Crushed + gallic acid (Cr+GA (50, 100, and 200 mg/kg/2 mL, orally, 6 Crushed + exercise (Cr+Exe, and 7 Crushed + exercise + effective dose of gallic acid (Cr+Exe +GA200 for 21 days. In order to establish an animal model of sciatic nerve crush, equivalent to 7 kg of force pressed on 2-3 mm of sciatic nerve for 30 s, three times with 30 s intervals. Pain sense reflex in hot plate, motor coordination in rotarod, and sciatic nerve conduction velocity (SNCV in all groups were tested. Data were analyzed using one-way ANOVA followed by Tukey’s post hoc test and pResults: Pain threshold was increased significantly in untreated crushed rats while motor function and SNCV were decreased in all groups with nerve crush (p

Immediate effects of the suboccipital muscle inhibition technique in craniocervical posture and greater occipital nerve mechanosensitivity in subjects with a history of orthodontia use: a randomized trial.

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Heredia Rizo, Alberto M; Pascual-Vaca, Ángel Oliva; Cabello, Manuel Albornoz; Blanco, Cleofás Rodríguez; Pozo, Fernando Piña; Carrasco, Antonio Luque

2012-07-01

The purpose of this study was to measure the immediate differences in craniocervical posture and pressure pain threshold of the greater occipital (GO) nerve in asymptomatic subjects with a history of having used orthodontics, after intervention by a suboccipital muscle inhibition (SMI) technique. This was a randomized, single-blind, clinical study with a sample of 24 subjects (21±1.78 years) that were divided into an experimental group (n=12) who underwent the SMI technique and a sham group (n=12) who underwent a sham (placebo) intervention. The sitting and standing craniovertebral angle and the pressure pain threshold of the GO nerve in both hemispheres were measured. The between-group comparison of the sample indicated that individuals subjected to the SMI technique showed a statistically significant increase in the craniovertebral angle in both the sitting (P<.001, F1,22=102.09, R2=0.82) and the standing (P<.001, F1,22=21.42, R2=0.56) positions and in the GO nerve pressure pain threshold in the nondominant hemisphere (P=.014, F1,22=7.06, R2=0.24). There were no statistically significant differences observed for the GO nerve mechanosensitivity in the dominant side (P=.202). Suboccipital muscle inhibition technique immediately improved the position of the head with the subject seated and standing, the clinical effect size being large in the former case. It also immediately decreased the mechanosensitivity of the GO nerve in the nondominant hemisphere, although the effect size was small. Copyright © 2012 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

Topiramate improves neurovascular function, epidermal nerve fiber morphology, and metabolism in patients with type 2 diabetes mellitus

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Boyd A

2010-12-01

Full Text Available Amanda L Boyd, Patricia M Barlow, Gary L Pittenger, Kathryn F Simmons, Aaron I VinikDepartment of Internal Medicine, Eastern Virginia Medical School, Norfolk, VA, USAPurpose: To assess the effects of topiramate on C-fiber function, nerve fiber morphology, and metabolism (including insulin sensitivity, obesity, and dyslipidemia in type 2 diabetes.Patients and methods: We conducted an 18-week, open-label trial treating patients with topiramate. Twenty subjects with type 2 diabetes and neuropathy (61.5 ± 1.29 years; 15 male, 5 female were enrolled and completed the trial. Neuropathy was evaluated by total neuropathy scores, nerve conduction studies, quantitative sensory tests, laser Doppler skin blood flow, and intraepidermal nerve fibers in skin biopsies.Results: Topiramate treatment improved symptoms compatible with C-fiber dysfunction. Weight, blood pressure, and hemoglobin A1c also improved. Laser Doppler skin blood flow improved significantly after 12 weeks of treatment, but returned to baseline at 18 weeks. After 18 weeks of treatment there was a significant increase in intraepidermal nerve fiber length at the forearm, thigh, and proximal leg. Intraepidermal nerve fiber density was significantly increased by topiramate in the proximal leg.Conclusion: This study is the first to demonstrate that it is possible to induce skin intraepidermal nerve fiber regeneration accompanied by enhancement of neurovascular function, translating into improved symptoms as well as sensory nerve function. The simultaneous improvement of selective metabolic indices may play a role in this effect, but this remains to be determined.Keywords: diabetic neuropathy, skin blood flow, skin biopsy, diabetes

Rodent model for assessing the long term safety and performance of peripheral nerve recording electrodes

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Vasudevan, Srikanth; Patel, Kunal; Welle, Cristin

2017-02-01

Objective. In the US alone, there are approximately 185 000 cases of limb amputation annually, which can reduce the quality of life for those individuals. Current prosthesis technology could be improved by access to signals from the nervous system for intuitive prosthesis control. After amputation, residual peripheral nerves continue to convey motor signals and electrical stimulation of these nerves can elicit sensory percepts. However, current technology for extracting information directly from peripheral nerves has limited chronic reliability, and novel approaches must be vetted to ensure safe long-term use. The present study aims to optimize methods to establish a test platform using rodent model to assess the long term safety and performance of electrode interfaces implanted in the peripheral nerves. Approach. Floating Microelectrode Arrays (FMA, Microprobes for Life Sciences) were implanted into the rodent sciatic nerve. Weekly in vivo recordings and impedance measurements were performed in animals to assess performance and physical integrity of electrodes. Motor (walking track analysis) and sensory (Von Frey) function tests were used to assess change in nerve function due to the implant. Following the terminal recording session, the nerve was explanted and the health of axons, myelin and surrounding tissues were assessed using immunohistochemistry (IHC). The explanted electrodes were visualized under high magnification using scanning electrode microscopy (SEM) to observe any physical damage. Main results. Recordings of axonal action potentials demonstrated notable session-to-session variability. Impedance of the electrodes increased upon implantation and displayed relative stability until electrode failure. Initial deficits in motor function recovered by 2 weeks, while sensory deficits persisted through 6 weeks of assessment. The primary cause of failure was identified as lead wire breakage in all of animals. IHC indicated myelinated and unmyelinated axons

[Effect of meliae toosendan fructus on nerves system and its mechanism].

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Xiang, Xiao-Xue; Tang, Da-Xuan; Xiong, Jing-Yue; Liang, Ya-Jun; Mu, Dao-Hua; Yang, Xiao-Wei; Hang, Min; Tan, Zheng-Huai

2013-05-01

To study the effect of the ethanol extract of stir-bake to yellowish Meliae Toosendan Fructus on nerve system and its mechanism. The effect of the ethanol extract on sensory nerve was carried out through ache models induced by hot board method and radiant heat stimulation method in mice. The thermalgesia liminal value was investigated. The effect of the ethanol extract on the A-delta fiber and C fiber was measured by electrical stimulation procedure. Motor nerve conduction velocity (NCV) was measured by indirect detection method in vivo. The pathology changes of the motor nerve were observed by transmission electron microscope and the silver stain test. The ethanol extract of Meliae Toosendan Fructus could increase the thermalgesia liminal value of mice and reduce the conduction velocity of motor nerves. Meanwhile, pathology results showed the changes of the fiber of motor nerve, including demyelination and the number of Schwann cells dropping. The ethanol extract of stir-bake to yellowish Meliae Toosendan Fructus can reduce the pain sensitivity of mice and slow down NCV, which may be related to decreasing of the number of Schwann cells.

The role of the renal afferent and efferent nerve fibres in heart failure

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Lindsea C Booth

2015-10-01

Full Text Available Renal nerves contain afferent, sensory and efferent, sympathetic nerve fibres. In heart failure (HF there is an increase in renal sympathetic nerve activity, which can lead to renal vasoconstriction, increased renin release and sodium retention. These changes are thought to contribute to renal dysfunction, which is predictive of poor outcome in patients with HF. In contrast, the role of the renal afferent nerves remains largely unexplored in HF. This is somewhat surprising as there are multiple triggers in HF that have the potential to increase afferent nerve activity, including increased venous pressure and reduced kidney perfusion. Some of the few studies investigating renal afferents in HF have suggested that at least the sympatho-inhibitory reno-renal reflex is blunted. In experimentally induced HF, renal denervation, both surgical and catheter-based, has been associated with some improvements in renal and cardiac function. It remains unknown whether the effects are due to removal of the efferent renal nerve fibres, afferent renal nerve fibres, or a combination of both. Here, we review the effects of HF on renal efferent and afferent nerve function and critically assess the latest evidence supporting renal denervation as a potential treatment in HF.

The role of the renal afferent and efferent nerve fibers in heart failure

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Booth, Lindsea C.; May, Clive N.; Yao, Song T.

2015-01-01

Renal nerves contain afferent, sensory and efferent, sympathetic nerve fibers. In heart failure (HF) there is an increase in renal sympathetic nerve activity (RSNA), which can lead to renal vasoconstriction, increased renin release and sodium retention. These changes are thought to contribute to renal dysfunction, which is predictive of poor outcome in patients with HF. In contrast, the role of the renal afferent nerves remains largely unexplored in HF. This is somewhat surprising as there are multiple triggers in HF that have the potential to increase afferent nerve activity, including increased venous pressure and reduced kidney perfusion. Some of the few studies investigating renal afferents in HF have suggested that at least the sympatho-inhibitory reno-renal reflex is blunted. In experimentally induced HF, renal denervation, both surgical and catheter-based, has been associated with some improvements in renal and cardiac function. It remains unknown whether the effects are due to removal of the efferent renal nerve fibers or afferent renal nerve fibers, or a combination of both. Here, we review the effects of HF on renal efferent and afferent nerve function and critically assess the latest evidence supporting renal denervation as a potential treatment in HF. PMID:26483699

Corticospinal inhibition of transmission in propriospinal-like neurones during human walking

DEFF Research Database (Denmark)

Iglesias, Caroline; Nielsen, Jens Bo; Marchand-Pauvert, Véronique

2008-01-01

It is crucial for human walking that muscles acting at different joints are optimally coordinated in relation to each other. This is ensured by interaction between spinal neuronal networks, sensory feedback and supraspinal control. Here we investigated the cortical control of spinal excitation from...... ankle dorsiflexor afferents to quadriceps motoneurones mediated by propriospinal-like interneurones. During walking and tonic contraction of ankle dorsiflexors and knee extensors while standing [at matched electromyography (EMG) levels], the effect of common peroneal nerve (CPN) stimulation...... was enhanced during walking, and when CPN stimulation was combined with FN or TMS, the resulting H-reflexes and MEPs were inhibited. The CPQ-reflex was also depressed when CPN stimulation was combined with subthreshold TMS. The peripheral (in CPN and FN) and corticospinal volleys may activate inhibitory non...

Comparison of ultrasound and ultrasound plus nerve stimulator guidance axillary plexus block

International Nuclear Information System (INIS)

Demirelli, G.; Baskan, S.; Karabeyoglu, I.; Aytac, I.; Omek, D.H.; Erdogmus, A.; Baydar, M.

2017-01-01

To evaluate the characteristics of axillary plexus blockade applied using ultrasound only and using ultrasound together with nerve stimulator in patients undergoing planned forearm, wrist or hand surgery. Methods: This randomised, prospective, double-blinded, single-centre study was conducted at Ankara Numune Training and Research Hospital, Ankara, Turkey, from November 2014 to August 2015, and comprised patients undergoing forearm, wrist or hand surgery. Participants were separated into 2 groups. In Group 1, the nerve roots required for the surgical site were located one by one and local anaesthetic was applied separately to each nerve for the block. In Group 2, the vascular nerve bundle was located under ultrasound guidance and a total block was achieved by administering all the local anaesthetic within the nerve sheath. In the operating room, standard monitorisation was applied. Following preparation of the skin, the axillary region nerve roots and branches and vascular structures were observed by examination with a high-frequency ultrasound probe. In both groups, a 22-gauge, 5cm block needle was entered to the axillary region with visualisation of the whole needle on ultrasound and 20ml local anaesthetic of 0.5% bupivacaine was injected. SPSS 19 was used for data analysis. Results: Of the 60 participants, there were 30(50%) in each group. The mean age was 39.1+-15 years in the group 1 which was the ultrasound nerve stimulation group, and 41.5+-14.3 years in group 2. The duration of the procedure was longer in group I than in group 2 (p<0.05). Patient satisfaction values during the procedure were higher in group 2(p<0.05). In the ulnar sensory examination, the values of the patients in group 1 were higher at 10, 15, 20 and 25 minutes (p<0.05). In the median, radial and ulnar motor examination, the values of the patients in group 1were higher at 15 and 20 minutes (p<0.05). Conclusion: Brachial plexus blockade via axillary approach guided by ultrasound offered

Large A-fiber activity is required for microglial proliferation and p38 MAPK activation in the spinal cord: different effects of resiniferatoxin and bupivacaine on spinal microglial changes after spared nerve injury

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Decosterd Isabelle

2009-09-01

Full Text Available Abstract Background After peripheral nerve injury, spontaneous ectopic activity arising from the peripheral axons plays an important role in inducing central sensitization and neuropathic pain. Recent evidence indicates that activation of spinal cord microglia also contributes to the development of neuropathic pain. In particular, activation of p38 mitogen-activated protein kinase (MAPK in spinal microglia is required for the development of mechanical allodynia. However, activity-dependent activation of microglia after nerve injury has not been fully addressed. To determine whether spontaneous activity from C- or A-fibers is required for microglial activation, we used resiniferatoxin (RTX to block the conduction of transient receptor potential vanilloid subtype 1 (TRPV1 positive fibers (mostly C- and Aδ-fibers and bupivacaine microspheres to block all fibers of the sciatic nerve in rats before spared nerve injury (SNI, and observed spinal microglial changes 2 days later. Results SNI induced robust mechanical allodynia and p38 activation in spinal microglia. SNI also induced marked cell proliferation in the spinal cord, and all the proliferating cells (BrdU+ were microglia (Iba1+. Bupivacaine induced a complete sensory and motor blockade and also significantly inhibited p38 activation and microglial proliferation in the spinal cord. In contrast, and although it produced an efficient nociceptive block, RTX failed to inhibit p38 activation and microglial proliferation in the spinal cord. Conclusion (1 Blocking peripheral input in TRPV1-positive fibers (presumably C-fibers is not enough to prevent nerve injury-induced spinal microglial activation. (2 Peripheral input from large myelinated fibers is important for microglial activation. (3 Microglial activation is associated with mechanical allodynia.

Sensory innervation of the temporomandibular joint in the mouse.

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Dreessen, D; Halata, Z; Strasmann, T

1990-01-01

The sensory innervation of the temporomandibular joints (TMJs) of 8 STR/IN mice was investigated by means of light and electron microscopy. Through the cutting of complete semithin sections in series it was possible to investigate the joints thoroughly. Additionally, one joint with its nerve supply was reconstructed three-dimensionally with a computerized three-dimensional programme. The reconstruction was based on one complete semithin section series. The joint's nerve supply originates from the nervus auriculotemporalis and additionally from motor branches of the n. mandibularis: n. massetericus, n. pterygoideus lateralis and the nn. temporales posteriores. The greatest number of nerve fibres and endings is located in the dorsolateral part of the joint capsule. They lie only in the stratum fibrosum and subsynovially. Neither the stratum synoviale nor the discus articularis contain any nerve fibres or endings, whereas the peri-articular loose connective tissue is richly innervated. The only type of nerve ending observed within the joint was the free nerve ending, which is assumed to serve not only as a nociceptor but also as a polymodal mechanoreceptor. Merely within the insertion of the musculus pterygoideus lateralis at the collum mandibulae single stretch receptors of the Ruffini type were observed. Ultrastructurally, they correspond to those described in the cat's knee joint. Neither lamellated nor nerve endings of the Golgi or Pacini type were observed in the joint or in the peri-articular connective tissue. The unexpected paucity of nerve fibres and endings in the TMJ itself of the mouse suggests that the afferent information from the joint is less important for position sense and movement than the afferent information from muscles, tendons and periodontal ligaments.

On the nature of the afferent fibers of oculomotor nerve.

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Manni, E; Draicchio, F; Pettorossi, V E; Carobi, C; Grassi, S; Bortolami, R; Lucchi, M L

1989-03-01

The oculogyric nerves contain afferent fibers originating from the ophthalmic territory, the somata of which are located in the ipsilateral semilunar ganglion. These primary sensory neurons project to the Subnucleus Gelatinosus of the Nucleus Caudalis Trigemini, where they make presynaptic contact with the central endings of the primary trigeminal afferents running in the fifth cranial nerve. After complete section of the trigeminal root, the antidromic volleys elicited in the trunk of the third cranial nerve by stimulating SG of NCT consisted of two waves belonging to the A delta and C groups. The area of both components of the antidromic volleys decreased both after bradykinin and hystamine injection into the corresponding cutaneous region and after thermic stimulation of the ipsilateral trigeminal ophthalmic territory. The reduction of such potentials can be explained in terms of collision between the antidromic volleys and those elicited orthodromically by chemical and thermic stimulation. Also, capsaicin applied on the nerve induced an immediate increase, followed by a long lasting decrease, of orthodromic evoked response area. These findings bring further support to the nociceptive nature of the afferent fibers running into the oculomotor nerve.

Efficacy of ultrasound and nerve stimulation guidance in peripheral nerve block: A systematic review and meta-analysis.

Science.gov (United States)

Wang, Zhi-Xue; Zhang, De-Li; Liu, Xin-Wei; Li, Yan; Zhang, Xiao-Xia; Li, Ru-Hong

2017-09-01

Evidence was controversial about whether nerve stimulation (NS) can optimize ultrasound guidance (US)-guided nerve blockade for peripheral nerve block. This review aims to explore the effects of the two combined techniques. We searched EMBASE (from 1974 to March 2015), PubMed (from 1966 to Mar 2015), Medline (from 1966 to Mar 2015), the Cochrane Central Register of Controlled Trials and clinicaltrials.gov. Finally, 15 randomized trials were included into analysis involving 1,019 lower limb and 696 upper limb surgery cases. Meta-analysis indicated that, compared with US alone, USNS combination had favorable effects on overall block success rate (risk ratio [RR] 1.17; confidence interval [CI] 1.05 to 1.30, P = 0.004), sensory block success rate (RR 1.56; CI 1.29 to 1.89, P block onset time (mean difference [MD] -3.84; CI -5.59 to -2.08, P block (MD 1.67; CI 1.32 to 2.02, P block onset time than US alone as well as higher block success rate, but no statistical difference was demonstrated, as more data are required. © 2017 IUBMB Life, 69(9):720-734, 2017. © 2017 International Union of Biochemistry and Molecular Biology.

Surgical outcomes following nerve transfers in upper brachial plexus injuries

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Bhandari P

2009-01-01

Full Text Available Background: Brachial plexus injuries represent devastating injuries with a poor prognosis. Neurolysis, nerve repair, nerve grafts, nerve transfer, functioning free-muscle transfer and pedicle muscle transfer are the main surgical procedures for treating these injuries. Among these, nerve transfer or neurotization is mainly indicated in root avulsion injury. Materials and Methods: We analysed the results of various neurotization techniques in 20 patients (age group 20-41 years, mean 25.7 years in terms of denervation time, recovery time and functional results. The inclusion criteria for the study included irreparable injuries to the upper roots of brachial plexus (C5, C6 and C7 roots in various combinations, surgery within 10 months of injury and a minimum follow-up period of 18 months. The average denervation period was 4.2 months. Shoulder functions were restored by transfer of spinal accessory nerve to suprascapular nerve (19 patients, and phrenic nerve to suprascapular nerve (1 patient. In 11 patients, axillary nerve was also neurotized using different donors - radial nerve branch to the long head triceps (7 patients, intercostal nerves (2 patients, and phrenic nerve with nerve graft (2 patients. Elbow flexion was restored by transfer of ulnar nerve motor fascicle to the motor branch of biceps (4 patients, both ulnar and median nerve motor fascicles to the biceps and brachialis motor nerves (10 patients, spinal accessory nerve to musculocutaneous nerve with an intervening sural nerve graft (1 patient, intercostal nerves (3rd, 4th and 5th to musculocutaneous nerve (4 patients and phrenic nerve to musculocutaneous nerve with an intervening graft (1 patient. Results: Motor and sensory recovery was assessed according to Medical Research Council (MRC Scoring system. In shoulder abduction, five patients scored M4 and three patients M3+. Fair results were obtained in remaining 12 patients. The achieved abduction averaged 95 degrees (range, 50 - 170

Clinical and imaging characteristics of foraminal nerve root disorders of the lumbar spine

International Nuclear Information System (INIS)

Nishi, Tomio; Tani, Takayuki; Suzuki, Norio; Aonuma, Hiroshi

2009-01-01

We analyzed cases of lumbar nerve root compression at intervertebral foramina, by comparing 19 cases of foraminal stenosis (FS), and 38 cases of foraminal hernia (FH) with 21 cases of lumbar canal stenosis (LCS). Japan Orthopedic Association (JOA) scores, intervertebral disc degeneration, anatomical measurements of the nerve root foramina and the MRI findings were reviewed. The scores for pain in the lower extremities, and walking ability were both lowest in the FS group. The scores for low back pain, lower extremities, and sensory disturbances were lowest in the FH group. Anterior-posterior diameters of the nerve root foramina were smaller in the FS group and FH group than in the LCS group. More degenerated discs and short length of upper part of the nerve root foramina were seen in FS group than in the other groups. The MRI images of so-called black out nerve root foramina were positive in 63.6% of FS cases, 75% of FH cases. (author)

Peripheral Nerve Dysfunction in Middle-Aged Subjects Born with Thalidomide Embryopathy.

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Alessia Nicotra

Full Text Available Phocomelia is an extremely rare congenital malformation that emerged as one extreme of a range of defects resulting from in utero exposure to thalidomide. Individuals with thalidomide embryopathy (TE have reported developing symptoms suggestive of peripheral nervous system dysfunction in the mal-developed limbs in later life.Case control study comparing TE subjects with upper limb anomalies and neuropathic symptoms with healthy controls using standard neurophysiological testing. Other causes of a peripheral neuropathy were excluded prior to assessment.Clinical examination of 17 subjects with TE (aged 50.4±1.3 [mean±standard deviation] years, 10 females and 17 controls (37.9±9.0 years; 8 females demonstrated features of upper limb compressive neuropathy in three-quarters of subjects. Additionally there were examination findings suggestive of mild sensory neuropathy in the lower limbs (n = 1, L5 radiculopathic sensory impairment (n = 1 and cervical myelopathy (n = 1. In TE there were electrophysiological changes consistent with a median large fibre neuropathic abnormality (mean compound muscle action potential difference -6.3 mV ([-9.3, -3.3], p = 0.0002 ([95% CI], p-value and reduced sympathetic skin response amplitudes (-0.8 mV ([-1.5, -0.2], p = 0.0089 in the affected upper limbs. In the lower limbs there was evidence of sural nerve dysfunction (sensory nerve action potential -5.8 μV ([-10.7, -0.8], p = 0.0232 and impaired warm perception thresholds (+3.0°C ([0.6, 5.4], p = 0.0169.We found a range of clinical features relevant to individuals with TE beyond upper limb compressive neuropathies supporting the need for a detailed neurological examination to exclude other treatable pathologies. The electrophysiological evidence of large and small fibre axonal nerve dysfunction in symptomatic and asymptomatic limbs may be a result of the original insult and merits further investigation.

Electrophysiological study in the infraorbital nerve of the rat: Spontaneous and evoked activity

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AlbarracIn, A L [Catedra de Neurociencias, Facultad de Medicina, Universidad Nacional de Tucuman, Av. Roca 2200, PC 4000 (Argentina); Farfan, F D [Departamento de BioingenierIa, FACET, Universidad Nacional de Tucuman, INSIBIO - CONICET, CC 327, PC 4000 (Argentina); Felice, C J [Departamento de BioingenierIa, FACET, Universidad Nacional de Tucuman, INSIBIO - CONICET, CC 327, PC 4000 (Argentina)

2007-11-15

In this work we present some studies in the afferent nerve of the rat vibrissae. Studies on spontaneous activity (SA) in this sensorial system are of long data. Nevertheless, SA recordings in the nerve of a single vibrissa have not been made until present. In this work, we use an algorithm based on signal decomposition with Continuous Wavelet Transform (CWT) to analyse the discharges of two nerves. The action potentials of both nerves were detected and the firing rates were calculated. These results suggest that the firing rate of one vibrissa innervation is low considering that this nerve contains hundred of fibers. In addition, we present preliminary studies suggesting important effects of the hair shaft length in the afferent discharge during the vibrissae movements. The experiments consisted in recording the nerve activity after the vibrissae were sectioned at two different levels. The results showed important differences in the signal energy contents. It suggests that the hair shaft length would produce a differential activation of the mechanoreceptors located in the vibrissae follicle.

Electrophysiological study in the infraorbital nerve of the rat: Spontaneous and evoked activity

International Nuclear Information System (INIS)

AlbarracIn, A L; Farfan, F D; Felice, C J

2007-01-01

In this work we present some studies in the afferent nerve of the rat vibrissae. Studies on spontaneous activity (SA) in this sensorial system are of long data. Nevertheless, SA recordings in the nerve of a single vibrissa have not been made until present. In this work, we use an algorithm based on signal decomposition with Continuous Wavelet Transform (CWT) to analyse the discharges of two nerves. The action potentials of both nerves were detected and the firing rates were calculated. These results suggest that the firing rate of one vibrissa innervation is low considering that this nerve contains hundred of fibers. In addition, we present preliminary studies suggesting important effects of the hair shaft length in the afferent discharge during the vibrissae movements. The experiments consisted in recording the nerve activity after the vibrissae were sectioned at two different levels. The results showed important differences in the signal energy contents. It suggests that the hair shaft length would produce a differential activation of the mechanoreceptors located in the vibrissae follicle

[A case of hereditary sensory and autonomic neuropathy type 1E with frontal lobe dysfunction as an initial symptom].

Science.gov (United States)

Watanabe, Masashi; Matsumoto, Yushi; Okamoto, Kensho; Okuda, Bungo; Mizuta, Ikuko; Mizuno, Toshiki

2017-12-27

A 49-year-old man had developed gradually personality change, gait disturbance, and hearing loss for five years. On admission, he presented with frontal release signs, stuttering, vertical gaze palsy, sensorineural deafness, muscle rigidity, ataxia, and sensory disturbance with areflexia in the lower extremities. Brain MRI demonstrated atrophy in the cerebellum and midbrain tegmentum as well as cerebral atrophy, predominantly in the frontal lobe. He was tentatively diagnosed as progressive supranuclear palsy on the basis of clinical features and imagings. On nerve conduction study, no sensory nerve action potentials were elicited in the upper and lower extremities. Details of family history revealed a hereditary sensory neuropathy with autosomal dominant inheritance in his relatives. Because genetic analysis showed a rare missense mutation (c.1483T>C, p.Y495H) in DNA methyltransferase 1 gene, we diagnosed him as having hereditary sensory and autonomic neuropathy type 1E (HSAN1E). In addition, p.M232R mutation in prion protein gene was detected. It should be kept in mind that there are some patients with HSAN1E presenting with frontal lobe dysfunction as an initial symptom and with clinical features mimicking progressive supranuclear palsy.

20.7 Peripheral nerve disease

Institute of Scientific and Technical Information of China (English)

1993-01-01

930394 A1—10 year follow—up study of 82cases of methamidophos induced delayedpolyneuropathy.Z1HENG Rongyuan (郑荣远),etal.Neurol Dept,Wenzhou Med Coll.325000.Chin J Industr Hyg & Occupat Dis 1992;10(6):344—347.A1—10 year follow—up study of 82 cases ofmethamidophos induced delayed polyneuropathywas reported.82 cases were classified into threetypes:motor (36.6%),sensory—motor (61%)and Guillain-Barre syndrome (2.4%).As awhole,the sensory disturbances disappearedwithin 2—3 months;the autonomic nerve func-tional disorder vanished within 3—6 months;

Surgical trainees neuropraxia? An unusual case of compression of the lateral cutaneous nerve of the forearm.

LENUS (Irish Health Repository)

Seoighe, D M

2010-09-01

Compression of the lateral cutaneous nerve of the forearm is an uncommon diagnosis but has been associated with strenuous upper limb activity. We report the unique case of a 32-year-old male orthopaedic trainee who suffered this nerve palsy as a result of prolonged elbow extension and forearm pronation while the single assistant during a hip resurfacing procedure. Conservative measures were sufficient for sensory recovery to be clinically detectable after 12 weeks.

Combination of heterologous fibrin sealant and bioengineered human embryonic stem cells to improve regeneration following autogenous sciatic nerve grafting repair.

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Mozafari, Roghayeh; Kyrylenko, Sergiy; Castro, Mateus Vidigal; Ferreira, Rui Seabra; Barraviera, Benedito; Oliveira, Alexandre Leite Rodrigues

2018-01-01

Peripheral nerve injury is a worldwide clinical problem, and the preferred surgical method for treating it is the end-to-end neurorrhaphy. When it is not possible due to a large nerve gap, autologous nerve grafting is used. However, these surgical techniques result in nerve regeneration at highly variable degrees. It is thus very important to seek complementary techniques to improve motor and sensory recovery. One promising approach could be cell therapy. Transplantation therapy with human embryonic stem cells (hESCs) is appealing because these cells are pluripotent and can differentiate into specialized cell types and have self-renewal ability. Therefore, the main objective of this study was to find conditions under which functional recovery is improved after sciatic nerve neurorrhaphy. We assumed that hESC, either alone or in combination with heterologous fibrin sealant scaffold, could be used to support regeneration in a mouse model of sciatic nerve injury and repair via autografting with end-to-end neurorrhaphy. Five millimeters of the sciatic nerve of C57BL/6 J mice were transected off and rotated 180 degrees to simulate an injury, and then stumps were sutured. Next, we applied heterologous fibrin sealant and/or human embryonic stem cells genetically altered to overexpress fibroblast growth factor 2 (FGF2) at the site of the injury. The study was designed to include six experimental groups comprising neurorrhaphy (N), neurorrhaphy + heterologous fibrin sealant (N + F), neurorrhaphy + heterologous fibrin sealant + doxycycline (N + F + D), neurorrhaphy + heterologous fibrin sealant + wild-type hESC (N + F + W), neurorrhaphy + heterologous fibrin sealant + hESC off (N + F + T), and neurorrhaphy + heterologous fibrin sealant + hESC on via doxycycline (N + F + D + T). We evaluated the recovery rate using Catwalk and von Frey functional recovery tests, as well as immunohistochemistry analysis. The experiments indicated that

An Important Chemical Weapon Group: Nerve Agents

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Hakan Yaren

2007-12-01

Full Text Available As a result of developing modern chemistry, nerve agents, which are one of the most important group of efficient chemical warfare agents, were developed just before Second World War. They generate toxic and clinical effects via inhibiting acetylcholinesterase irreversibly and causing excessive amounts of acetylcholine at cholinergic synapses in the body. Clinical symptoms are occurred as a result of affected muscarinic (stimulation of secretuar glands, miosis, breathing problems etc., nicotinic (stimulation of skeletal muscles, paralyse, tremors etc. and central nerve system (convulsions, loss of consciousness, coma etc. areas. In case of a nerve agent exposure, treatment includes the steps of ventilation, decontamination, antidotal treatment (atropine, oximes, diazepam and pyridostigmine bromide and supportive theraphy. Because of arising possibility of using chemical warfare agents due to current conjuncture of the world, medical staff should know about nerve agents, their effects and how to treat the casualties exposured to nerve agents. [TAF Prev Med Bull 2007; 6(6.000: 491-500

An Important Chemical Weapon Group: Nerve Agents

Directory of Open Access Journals (Sweden)

Hakan Yaren

2007-12-01

Full Text Available As a result of developing modern chemistry, nerve agents, which are one of the most important group of efficient chemical warfare agents, were developed just before Second World War. They generate toxic and clinical effects via inhibiting acetylcholinesterase irreversibly and causing excessive amounts of acetylcholine at cholinergic synapses in the body. Clinical symptoms are occurred as a result of affected muscarinic (stimulation of secretuar glands, miosis, breathing problems etc., nicotinic (stimulation of skeletal muscles, paralyse, tremors etc. and central nerve system (convulsions, loss of consciousness, coma etc. areas. In case of a nerve agent exposure, treatment includes the steps of ventilation, decontamination, antidotal treatment (atropine, oximes, diazepam and pyridostigmine bromide and supportive theraphy. Because of arising possibility of using chemical warfare agents due to current conjuncture of the world, medical staff should know about nerve agents, their effects and how to treat the casualties exposured to nerve agents. [TAF Prev Med Bull. 2007; 6(6: 491-500

Injury to the Infrapatellar Branch of the Saphenous Nerve during ACL Reconstruction with Hamstring Tendon Autograft: A Comparison between Oblique and Vertical Incisions

Directory of Open Access Journals (Sweden)

Hamid Mousavi

2018-01-01

Full Text Available Background: Injury to the infrapatellar branch of the saphenous nerve (IPBSN is common after arthroscopic ACLreconstruction with hamstring tendon autograft, as reported in up to 88% of the cases. Due to close relationshipbetween the IPBSN with pes anserine tendons insertion skin incision may sever IPBSN while harvesting gracillis andsemitendinous tendons. As the IPBSN course at the anterior of knee is oblique, we hypothesized a parallel skin incisionwith nerve passage may decrease nerve injury.Methods: Vertical and oblique incisions were compared in 79 patients in this clinical trial. The sensory loss area andpatients’ complain of numbness were measured at 2 and 8 weeks as well as 6 months after surgery.Results: Both the sensory loss area and patients’ complain of numbness decreased significantly in the oblique incisiongroup (P

Terminal-Nerve-Derived Neuropeptide Y Modulates Physiological Responses in the Olfactory Epithelium of Hungry Axolotls (Ambystoma mexicanum)

OpenAIRE

Mousley, Angela; Polese, Gianluca; Marks, Nikki J.; Eisthen, Heather L.

2006-01-01

The vertebrate brain actively regulates incoming sensory information, effectively filtering input and focusing attention toward environmental stimuli that are most relevant to the animal's behavioral context or physiological state. Such centrifugal modulation has been shown to play an important role in processing in the retina and cochlea, but has received relatively little attention in olfaction. The terminal nerve, a cranial nerve that extends underneath the lamina propria surrounding the o...

PERIPHERAL SENSORY NEURONS EXPRESSING MELANOPSIN RESPOND TO LIGHT

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Anna Matynia

2016-08-01

Full Text Available The ability of light to cause pain is paradoxical. The retina detects light but is devoid of nociceptors while the trigeminal sensory ganglia (TG contain nociceptors but not photoreceptors. Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs are thought to mediate light-induced pain but recent evidence raises the possibility of an alternative light responsive pathway independent of the retina and optic nerve. Here, we show that melanopsin is expressed in both human and mouse TG neurons. In mice, they represent 3% of small TG neurons that are preferentially localized in the ophthalmic branch of the trigeminal nerve and are likely nociceptive C fibers and high-threshold mechanoreceptor Aδ fibers based on a strong size-function association. These isolated neurons respond to blue light stimuli with a delayed onset and sustained firing, similar to the melanopsin-dependent intrinsic photosensitivity observed in ipRGCs. Mice with severe bilateral optic nerve crush exhibit no light-induced responses including behavioral light aversion until treated with nitroglycerin, an inducer of migraine in people and migraine-like symptoms in mice. With nitroglycerin, these same mice with optic nerve crush exhibit significant light aversion. Furthermore, this retained light aversion remains dependent on melanopsin-expressing neurons. Our results demonstrate a novel light-responsive neural function independent of the optic nerve that may originate in the peripheral nervous system to provide the first direct mechanism for an alternative light detection pathway that influences motivated behavior.

Serum levels of TGF-β1 in patients of diabetic peripheral neuropathy and its correlation with nerve conduction velocity in type 2 diabetes mellitus.

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Hussain, Gauhar; Rizvi, S Aijaz Abbas; Singhal, Sangeeta; Zubair, Mohammad; Ahmad, Jamal

2016-01-01

To correlate serum levels of TGF-β1 with motor and sensory nerve conduction velocities in patients of type 2 diabetes mellitus The study was conducted in diagnosed type 2 diabetes mellitus patients which were divided in patients with clinically detectable peripheral neuropathy of shorter duration (n=37) and longer duration (n=27). They were compared with patients without clinical neuropathy (n=22). Clinical diagnosis was based on neuropathy symptom score (NSS) and Neuropathy disability score (NDS) for signs. Blood samples were collected for baseline investigations and estimation of serum TGF-β1. Nerve conduction velocity was measured in both upper and lower limbs. Median, Ulnar, Common Peroneal and Posterior Tibial nerves were selected for motor nerve conduction study and Median and Sural nerves were selected for sensory nerve conduction study In patients of type 2 diabetes mellitus with clinically detectable and serum TGF-β1 showed positive correlation with nerve conduction velocities High level of TGF-β1 in serum of T2DM patients with neuropathy show possible contribution in development of neuropathy. Due to its independent association this cytokine might be used as biomarker for diabetic peripheral neuropathy. Copyright © 2015 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Can nerve regeneration on an artificial nerve conduit be enhanced by ethanol-induced cervical sympathetic ganglion block?

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Yoshiki Shionoya

Full Text Available This study aimed to determine whether nerve regeneration by means of an artificial nerve conduit is promoted by ethanol-induced cervical sympathetic ganglion block (CSGB in a canine model. This study involved two experiments-in part I, the authors examined the effect of CSGB by ethanol injection on long-term blood flow to the orofacial region; part II involved evaluation of the effect of CSGB by ethanol injection on inferior alveolar nerve (IAN repair using polyglycolic acid-collagen tubes. In part I, seven Beagles were administered left CSGB by injection of 99.5% ethanol under direct visualization by means of thoracotomy, and changes in oral mucosal blood flow in the mental region and nasal skin temperature were evaluated. The increase in blood flow on the left side lasted for 7 weeks, while the increase in average skin temperature lasted 10 weeks on the left side and 3 weeks on the right. In part II, fourteen Beagles were each implanted with a polyglycolic acid-collagen tube across a 10-mm gap in the left IAN. A week after surgery, seven of these dogs were administered CSGB by injection of ethanol. Electrophysiological findings at 3 months after surgery revealed significantly higher sensory nerve conduction velocity and recovery index (ratio of left and right IAN peak amplitudes after nerve regeneration in the reconstruction+CSGB group than in the reconstruction-only group. Myelinated axons in the reconstruction+CSGB group were greater in diameter than those in the reconstruction-only group. Administration of CSGB with ethanol resulted in improved nerve regeneration in some IAN defects. However, CSGB has several physiological effects, one of which could possibly be the long-term increase in adjacent blood flow.

Can nerve regeneration on an artificial nerve conduit be enhanced by ethanol-induced cervical sympathetic ganglion block?

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