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1

The relationship of nerve fibre pathology to sensory function in entrapment neuropathy  

PubMed Central

Surprisingly little is known about the impact of entrapment neuropathy on target innervation and the relationship of nerve fibre pathology to sensory symptoms and signs. Carpal tunnel syndrome is the most common entrapment neuropathy; the aim of this study was to investigate its effect on the morphology of small unmyelinated as well as myelinated sensory axons and relate such changes to somatosensory function and clinical symptoms. Thirty patients with a clinical and electrophysiological diagnosis of carpal tunnel syndrome [17 females, mean age (standard deviation) 56.4 (15.3)] and 26 age and gender matched healthy volunteers [18 females, mean age (standard deviation) 51.0 (17.3)] participated in the study. Small and large fibre function was examined with quantitative sensory testing in the median nerve territory of the hand. Vibration and mechanical detection thresholds were significantly elevated in patients with carpal tunnel syndrome (P < 0.007) confirming large fibre dysfunction and patients also presented with increased thermal detection thresholds (P < 0.0001) indicative of C and A?-fibre dysfunction. Mechanical and thermal pain thresholds were comparable between groups (P > 0.13). A skin biopsy was taken from a median nerve innervated area of the proximal phalanx of the index finger. Immunohistochemical staining for protein gene product 9.5 and myelin basic protein was used to evaluate morphological features of unmyelinated and myelinated axons. Evaluation of intraepidermal nerve fibre density showed a striking loss in patients (P < 0.0001) confirming a significant compromise of small fibres. The extent of Meissner corpuscles and dermal nerve bundles were comparable between groups (P > 0.07). However, patients displayed a significant increase in the percentage of elongated nodes (P < 0.0001), with altered architecture of voltage-gated sodium channel distribution. Whereas neither neurophysiology nor quantitative sensory testing correlated with patients’ symptoms or function deficits, the presence of elongated nodes was inversely correlated with a number of functional and symptom related scores (P < 0.023). Our findings suggest that carpal tunnel syndrome does not exclusively affect large fibres but is associated with loss of function in modalities mediated by both unmyelinated and myelinated sensory axons. We also document for the first time that entrapment neuropathies lead to a clear reduction in intraepidermal nerve fibre density, which was independent of electrodiagnostic test severity. The presence of elongated nodes in the target tissue further suggests that entrapment neuropathies affect nodal structure/myelin well beyond the focal compression site. Interestingly, nodal lengthening may be an adaptive phenomenon as it inversely correlates with symptom severity. PMID:25348629

Schmid, Annina B.; Bland, Jeremy D. P.; Bhat, Manzoor A.

2014-01-01

2

Roles of sensory nerves in the regulation of radiation-induced structural and functional changes in the heart  

PubMed Central

Purpose Radiation-induced heart disease (RIHD) is a chronic severe side effect of radiotherapy of intrathoracic and chest wall tumors. The heart contains a dense network of sensory neurons that are not only involved in monitoring of cardiac events such as ischemia/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, two weeks before local image-guided heart X-ray irradiation with a single dose of 21 Gy. During the 6-months follow up time, 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-Blots. Results Capsaicin-pretreatment blunted the effects of radiation on myocardial fibrosis and mast cell infiltration and activity. On the other hand, capsaicin-pretreatment caused a small but significant reduction in cardiac output at 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, while playing a predominantly protective role in radiation-induced cardiac function changes, may eventually enhance radiation-induced myocardial fibrosis and mast cell activity. PMID:24331664

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

2013-01-01

3

Pharmacologic rescue of motor and sensory function by the neuroprotective compound P7C3 following neonatal nerve injury.  

PubMed

Nerve injuries cause pain, paralysis and numbness that can lead to major disability, and newborns often sustain nerve injuries during delivery that result in lifelong impairment. Without a pharmacologic agent to enhance functional recovery from these injuries, clinicians rely solely on surgery and rehabilitation to treat patients. Unfortunately, patient outcomes remain poor despite application of the most advanced microsurgical and rehabilitative techniques. We hypothesized that the detrimental effects of traumatic neonatal nerve injury could be mitigated with pharmacologic neuroprotection, and tested whether the novel neuroprotective agent P7C3 would block peripheral neuron cell death and enhance functional recovery in a rat neonatal nerve injury model. Administration of P7C3 after sciatic nerve crush injury doubled motor and sensory neuron survival, and also promoted axon regeneration in a dose-dependent manner. Treatment with P7C3 also enhanced behavioral and muscle functional recovery, and reversed pathological mobilization of spinal microglia after injury. Our findings suggest that the P7C3 family of neuroprotective compounds may provide a basis for the development of a new neuroprotective drug to enhance recovery following peripheral nerve injury. PMID:25313000

Kemp, S W P; Szynkaruk, M; Stanoulis, K N; Wood, M D; Liu, E H; Willand, M P; Morlock, L; Naidoo, J; Williams, N S; Ready, J M; Mangano, T J; Beggs, S; Salter, M W; Gordon, T; Pieper, A A; Borschel, G H

2015-01-22

4

Inhibitory activity of the novel CB2 receptor agonist, GW833972A, on guinea-pig and human sensory nerve function in the airways  

PubMed Central

Background and purpose: Sensory nerves regulate central and local reflexes such as airway plasma protein leakage, bronchoconstriction and cough. Sensory nerve activity may be enhanced during inflammation such that these protective effects become exacerbated and deleterious. Cannabinoids are known to inhibit airway sensory nerve function. However, there is still controversy surrounding which receptor is involved in eliciting these effects. Experimental approach: We have adopted a pharmacological approach, including using a novel, more selective CB2 receptor agonist, GW 833972A (1000-fold selective CB2/CB1), and receptor selective antagonists to investigate the inhibitory activity of cannabinoids on sensory nerve activity in vitro and in vivo in guinea-pig models of cough and plasma extravasation. Key results: GW 833972A inhibited capsaicin-induced depolarization of the human and guinea-pig and prostaglandin E2 (PGE2) and hypertonic saline-induced depolarization of the guinea-pig isolated vagus nerve in vitro. GW 833972A also inhibited citric acid-induced cough but not plasma extravasation in the guinea-pig and this effect was blocked by a CB2 receptor antagonist. Conclusions and implications: This confirms and extends previous studies highlighting the role of CB2 receptors in the modulation of sensory nerve activity elicited both by the exogenous ligands capsaicin and hypertonic saline but also by endogenous modulators such as PGE2 and low pH stimuli. These data establish the CB2 receptor as an interesting target for the treatment of chronic cough. PMID:18695648

Belvisi, M G; Patel, H J; Freund-Michel, V; Hele, D J; Crispino, N; Birrell, M A

2008-01-01

5

Sensory nerve conduction of the plantar nerve compared with other nerve conduction tests in rats  

Microsoft Academic Search

ObjectiveIn rats the available techniques for evaluation of sensory nerve conduction are limited. We report a new method of sensory nerve conduction of the plantar nerve using needle electrodes as the recording electrodes behind the medial malleolus and ring electrodes as the stimulating electrodes around the three middle toes.

Katsumi Kurokawa; Diogo F de Almeida; Yun Zhang; Charles D Hébert; John G Page; Karen M Schweikart; Shin J Oh

2004-01-01

6

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

PubMed

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 A? 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 A? fibres. There is also some evidence that as a result of inflammation in the airways, A? 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 continuous monitoring methodologies for measuring cough will hopefully allow better evaluation of treatments in patients with chronic cough. Nonetheless, cough remains a major unmet clinical need in respiratory medicine where new drugs are urgently required. PMID:23524012

Spina, D; Page, C P

2013-10-01

7

Prolonged sensory-selective nerve blockade.  

PubMed

Sensory-selective local anesthesia has long been a key goal in local anesthetic development. For example, it allows women to be pain-free during labor without compromising their ability to push. Here we show that prolonged sensory-selective nerve block can be produced by specific concentrations of surfactants-such as are used to enhance drug flux across skin-in combination with QX-314, a lidocaine derivative that has relative difficulty penetrating nerves. For example, injection of 25 mM QX-314 in 30 mM octyltrimethylammonium bromide (OTAB) lasted up to 7 h. Sensory selectivity was imparted to varying degrees by cationic, neutral, and anionic surfactants, and also was achieved with another lidocaine derivative, QX-222. Simultaneous injection of OTAB at a s.c. injection site remote from the sciatic nerve did not result in prolonged sensory-specific nerve blockade from QX-314, suggesting that the observed effect is due to a local interaction between the surfactant and the lidocaine derivative, not a systemic effect. PMID:20133669

Sagie, Itay; Kohane, Daniel S

2010-02-23

8

Nerve Growth Factor Decreases in Sympathetic and Sensory Nerves of Rats with Chronic Heart Failure  

PubMed Central

Nerve growth factor (NGF) plays a critical role in the maintenance and survival of both sympathetic and sensory nerves. Also, NGF can regulate receptor expression and neuronal activity in the sympathetic and sensory neurons. Abnormalities in NGF regulation are observed in patients and animals with heart failure (HF). Nevertheless, the effects of chronic HF on the levels of NGF within the sympathetic and sensory nerves are not known. Thus, the ELISA method was used to assess the levels of NGF in the stellate ganglion (SG) and dorsal root ganglion (DRG) neurons of control rats and rats with chronic HF induced by myocardial infarction. Our data show for the first time that the levels of NGF were significantly decreased (P < 0.05) in the SG and DRG neurons 6–20 weeks after ligation of the coronary artery. In addition, a close relation was observed between the NGF levels and the left ventricular function. In conclusion, chronic HF impairs the expression of NGF in the sympathetic and sensory nerves. Given that sensory afferent nerves are engaged in the sympathetic nervous responses to somatic stimulation (i.e. muscle activity during exercise) via a reflex mechanism, our data indicate that NGF is likely responsible for the development of muscle reflex-mediated abnormal sympathetic responsiveness observed in chronic HF. PMID:24913185

Lu, Jian

2014-01-01

9

The effect of treatment with BRX-220, a co-inducer of heat shock proteins, on sensory fibers of the rat following peripheral nerve injury  

E-print Network

of the rat following peripheral nerve injury B. Kalmar,a,b,* L. Greensmith,a M. Malcangio,c S.B. McMahon,c P sciatic nerve injury in adult rats and treatment with BRX-220, the following features of the sensory and functional properties in the sensory system following peripheral nerve injury. D 2003 Elsevier Inc. All

Burnstock, Geoffrey

10

Sensory Nerve Innervation of Epineurial Arterioles of the Sciatic Nerve Containing Calcitonin Gene–Related Peptide: Effect of Streptozotocin-Induced Diabetes  

PubMed Central

The authors have determined that epineurial arterioles of the sciatic nerve are innervated by nonadrenergic, noncholinergic nerves that contribute to the regulation of vasodilation. Using immunohistochemistry, the authors determined that nerves innervating epineurial arterioles contain the neuropeptide calcitonin gene–related peptide (CGRP). Using streptozotocin-induced diabetic rats, the authors demonstrated that CGRP content in sensory nerves innervating epineurial arterioles and vasodilation in response to exogenous CGRP was decreased. In summary, epineurial arterioles of the sciatic nerve are innervated by sensory nerves containing the neuropeptide CGRP. The diabetes-like condition induced by streptozotocin reduces the content of CGRP in these nerves and exogenous CGRPmediated vasodilation. CGRP is likely an important regulator of vascular tone and compromising its function could contribute to nerve ischemia and diabetic neuropathy. PMID:15512786

Coppey, L. J.; Gellett, J. S.; Davidson, E. P.

2004-01-01

11

Sensory reinnervation of muscle spindles after repair of tibial nerve defects using autogenous vein grafts  

PubMed Central

Motor reinnervation after repair of tibial nerve defects using autologous vein grafts in rats has previously been reported, but sensory reinnervation after the same repair has not been fully investigated. In this study, partial sensory reinnervation of muscle spindles was observed after repair of 10-mm left tibial nerve defects using autologous vein grafts with end-to-end anastomosis in rats, and functional recovery was confirmed by electrophysiological studies. There were no significant differences in the number, size, or electrophysiological function of reinnervated muscle spindles between the two experimental groups. These findings suggest that repair of short nerve defects with autologous vein grafts provides comparable results to immediate end-to-end anastomosis in terms of sensory reinnervation of muscle spindles. PMID:25206863

Pang, Youwang; Hong, Qingnan; Zheng, Jinan

2014-01-01

12

A reversible functional sensory neuropathy model.  

PubMed

Small-fiber neuropathy was induced in young adult mice by intraperitoneal injection of resiniferatoxin (RTX), a TRPV1 agonist. At day 7, RTX induced significant thermal and mechanical hypoalgesia. At day 28, mechanical and thermal nociception were restored. No nerve degeneration in skin was observed and unmyelinated nerve fiber morphology and density in sciatic nerve were unchanged. At day 7, substance P (SP) was largely depleted in dorsal root ganglia (DRG) neurons, although calcitonin gene-related peptide (CGRP) was only moderately depleted. Three weeks after, SP and CGRP expression was restored in DRG neurons. At the same time, CGRP expression remained low in intraepidermal nerve fibers (IENFs) whereas SP expression had improved. In summary, RTX induced in our model a transient neuropeptide depletion in sensory neurons without nerve degeneration. We think this model is valuable as it brings the opportunity to study functional nerve changes in the very early phase of small fiber neuropathy. Moreover, it may represent a useful tool to study the mechanisms of action of therapeutic strategies to prevent sensory neuropathy of various origins. PMID:24792390

Danigo, Aurore; Magy, Laurent; Richard, Laurence; Sturtz, Franck; Funalot, Benoît; Demiot, Claire

2014-06-13

13

Sensory nerve-mediated nasal vasodilatory response to inspired ethyl acrylate.  

PubMed

The irritants acrolein, acetaldehyde, and acetic acid induce a rapid sensory nerve-mediated nasal vasodilatory response in the rat. The aim of the current study was to examine acute nasal sensory nerve-mediated acute responses to an irritant ester vapor, ethyl acrylate. For this purpose, the upper respiratory tract of the urethane-anesthetized male F344 rat was isolated by insertion of an endotracheal cannula, and ethyl acrylate-laden air was drawn continuously through that site at a flow rate of 100 ml/min for 50 min. Vascular function was monitored by measuring inert vapor (acetone) uptake throughout the exposure. Nasal flow resistance was also monitored during exposure, and plasma protein extravasation was measured by Evans blue dye leakage. At exposure concentrations of 100 to 400 ppm, ethyl acrylate induced a rapid nasal vasodilatory response, as indicated by increased acetone uptake rates. This response was maintained throughout the exposure. Changes in nasal flow resistance or in Evans blue dye leakage were not observed at these exposure concentrations. The vasodilatory response was diminished in animals pretreated with the sensory nerve toxin capsaicin, providing strong evidence that this response was sensory nerve mediated. Pretreatment with the carboxylesterase inhibitor bis-para-nitro-phenolphospahte at a dose sufficient to inhibit nasal carboxylesterase did not alter the response, suggesting that the parent ester, not the carboxylesterase metabolites, is primarily responsible for the sensory-nerve-mediated vasodilatory responses to this ester. PMID:12119070

Morris, John B

2002-06-01

14

Factors predicting sensory and motor recovery after the repair of upper limb peripheral nerve injuries  

PubMed Central

OBJECTIVE: To investigate the factors associated with sensory and motor recovery after the repair of upper limb peripheral nerve injuries. DATA SOURCES: The online PubMed database was searched for English articles describing outcomes after the repair of median, ulnar, radial, and digital nerve injuries in humans with a publication date between 1 January 1990 and 16 February 2011. STUDY SELECTION: The following types of article were selected: (1) clinical trials describing the repair of median, ulnar, radial, and digital nerve injuries published in English; and (2) studies that reported sufficient patient information, including age, mechanism of injury, nerve injured, injury location, defect length, repair time, repair method, and repair materials. SPSS 13.0 software was used to perform univariate and multivariate logistic regression analyses and to investigate the patient and intervention factors associated with outcomes. MAIN OUTCOME MEASURES: Sensory function was assessed using the Mackinnon-Dellon scale and motor function was assessed using the manual muscle test. Satisfactory motor recovery was defined as grade M4 or M5, and satisfactory sensory recovery was defined as grade S3+ or S4. RESULTS: Seventy-one articles were included in this study. Univariate and multivariate logistic regression analyses showed that repair time, repair materials, and nerve injured were independent predictors of outcome after the repair of nerve injuries (P < 0.05), and that the nerve injured was the main factor affecting the rate of good to excellent recovery. CONCLUSION: Predictors of outcome after the repair of peripheral nerve injuries include age, gender, repair time, repair materials, nerve injured, defect length, and duration of follow-up. PMID:25206870

He, Bo; Zhu, Zhaowei; Zhu, Qingtang; Zhou, Xiang; Zheng, Canbin; Li, Pengliang; Zhu, Shuang; Liu, Xiaolin; Zhu, Jiakai

2014-01-01

15

Noninvasive Peroneal Sensory and Motor Nerve Conduction Recordings in the Rabbit Distal Hindlimb: Feasibility, Variability and Neuropathy Measure  

PubMed Central

The peroneal nerve anatomy of the rabbit distal hindlimb is similar to humans, but reports of distal peroneal nerve conduction studies were not identified with a literature search. Distal sensorimotor recordings may be useful for studying rabbit models of length-dependent peripheral neuropathy. Surface electrodes were adhered to the dorsal rabbit foot overlying the extensor digitorum brevis muscle and the superficial peroneal nerve. The deep and superficial peroneal nerves were stimulated above the ankle and the common peroneal nerve was stimulated at the knee. The nerve conduction studies were repeated twice with a one-week intertest interval to determine measurement variability. Intravenous vincristine was used to produce a peripheral neuropathy. Repeat recordings measured the response to vincristine. A compound muscle action potential and a sensory nerve action potential were evoked in all rabbits. The compound muscle action potential mean amplitude was 0.29 mV (SD ± 0.12) and the fibula head to ankle mean motor conduction velocity was 46.5 m/s (SD ± 2.9). The sensory nerve action potential mean amplitude was 22.8 ?V (SD ± 2.8) and the distal sensory conduction velocity was 38.8 m/s (SD ± 2.2). Sensorimotor latencies and velocities were least variable between two test sessions (coefficient of variation ?=? 2.6–5.9%), sensory potential amplitudes were intermediate (coefficient of variation ?=? 11.1%) and compound potential amplitudes were the most variable (coefficient of variation ?=?19.3%). Vincristine abolished compound muscle action potentials and reduced sensory nerve action potential amplitudes by 42–57% while having little effect on velocity. Rabbit distal hindlimb nerve conduction studies are feasible with surface recordings and stimulation. The evoked distal sensory potentials have amplitudes, configurations and recording techniques that are similar to humans and may be valuable for measuring large sensory fiber function in chronic models of peripheral neuropathies. PMID:24658286

Hotson, John R.

2014-01-01

16

Photodamage to the cutaneous sensory nerves: role in photoaging and carcinogenesis of the skin?  

PubMed

Chronic exposure to ultraviolet radiation (UVR) plays a significant role in aging and carcinogenesis of the skin. Sensory nerve fibers densely innervate all layers of the skin and get in close anatomical as well as functional contact with cellular components of the epidermis and dermis. In this review, we address the impact of acute and chronic UVR exposure on the cutaneous sensory nervous system and its mediators. We suggest that skin cell-derived nerve growth factor (NGF) and skin nerve-derived neuropeptides such as substance P (SP) and calcitonin gene-related peptide (CGRP) may play a central role in intrinsic aging as well as extrinsic (photo-) aging of the skin. In addition, we discuss the possible role of these mediators in photocarcinogenesis. PMID:16465302

Legat, Franz J; Wolf, Peter

2006-02-01

17

CAPSAICIN-SENSITIVE SENSORY NERVE FIBERS CONTRIBUTE TO THE GENERATION AND MAINTENANCE OF SKELETAL FRACTURE PAIN  

PubMed Central

Although skeletal pain can have a marked impact on a patient’s functional status and quality of life, relatively little is known about the specific populations of peripheral nerve fibers that drive non-malignant bone pain. In the present report, neonatal male Sprague Dawley rats were treated with capsaicin or vehicle and femoral fracture was produced when the animals were young adults (15–16 weeks old). Capsaicin treatment, but not vehicle, resulted in a significant (>70%) depletion in the density of calcitonin-gene related peptide positive (CGRP+) sensory nerve fibers, but not 200 kD neurofilament H positive (NF200+) sensory nerve fibers in the periosteum. The periosteum is a thin, cellular and fibrous tissue that tightly adheres to the outer surface of all but the articulated surface of bone and appears to play a pivotal role in driving fracture pain. In animals treated with capsaicin, but not vehicle, there was a 50% reduction in the severity, but no change in the time course, of fracture-induced skeletal pain related behaviors as measured by spontaneous flinching, guarding and weight bearing. These results suggest that both capsaicin-sensitive (primarily CGRP+ C-fibers) and capsaicin-insensitive (primarily NF200+ A-delta fibers) sensory nerve fibers participate in driving skeletal fracture pain. Skeletal pain can be a significant impediment to functional recovery following trauma-induced fracture, osteoporosis-induced fracture and orthopedic surgery procedures such as knee and hip replacement. Understanding the specific populations of sensory nerve fibers that need to be targeted to inhibit the generation and maintenance of skeletal pain may allow the development of more specific mechanism-based therapies that can effectively attenuate acute and chronic skeletal pain. PMID:19486928

Jimenez-Andrade, Juan Miguel; Bloom, Aaron P.; Mantyh, William G.; Koewler, Nathan J.; Freeman, Katie T.; Delong, David; Ghilardi, Joseph R.; Kuskowski, Michael A.; Mantyh, Patrick W.

2009-01-01

18

Sickle cell disease in mice is associated with sensitization of sensory nerve fibers.  

PubMed

The pain phenotype in sickle cell disease (SCD) patients is highly variable. A small percentage of SCD patients experience many vaso-occlusive crises/year, 5% of patients account for over 30% of pain episodes, while 39% report few episodes of severe pain. Clearly, a better understanding of the pathobiology of SCD is needed to improve its therapy. Humanized sickle cell mice recapitulate several phenotypes of SCD patients and provide a model for the study of SCD pain. Researchers have shown that one strain of humanized SCD mice, the BERK strain, has abnormal pain phenotype. However, the nociception phenotype of another humanized SCD mouse strain, the Townes strain, has not been described. In a large cross-sectional study of BERK and Townes SCD mice, we examined thermosensory response and sensory nerve fiber function using sine-wave electrical stimulation at 2000, 250, and 5?Hz to stimulate preferentially A?, A?, and C sensory nerve fibers, respectively. We found that BERK and Townes mice, compared to respective controls, had decreases in 2000, 250, and 5?Hz current vocalization thresholds in patterns that suggest sensitization of a broad spectrum of sensory nerve fibers. In addition, the pattern of sensitization of sensory fibers varied according to strain, sex, age, and mouse genotype. In a similarly variable pattern, Townes and BERKs also had significantly altered sensitivity to noxious thermal stimuli in agreement with what has been shown by others. In summary, the analysis of somatosensory function using sine-wave electrical stimulation in humanized sickle cell mice suggests that in SCD, both myelinated and unmyelinated, fibers are sensitized. The pattern of sensory fiber sensitization is distinct from that observed in pain models of neuropathic and inflammatory pain. These findings raise the possibility that sensitization of a broad spectrum of sensory fibers might contribute to the altered and variable nociception phenotype in SCD. PMID:25070860

Kenyon, Nicholas; Wang, Li; Spornick, Nicholas; Khaibullina, Alfia; Almeida, Luis Ef; Cheng, Yao; Wang, Jichuan; Guptill, Virginia; Finkel, Julia C; Quezado, Zenaide Mn

2015-01-01

19

Uses of Skin Biopsy for Sensory and Autonomic Nerve Assessment  

PubMed Central

Skin biopsy is a valuable diagnostic tool for small-fiber-predominant neuropathy by the quantification of intra-epidermal nerve fiber density (IENFD). It has the unique advantage of being a minimally invasive procedure with the potential for longitudinal evaluation of both sensory and autonomic fibers. Unmyelinated small fibers are not otherwise quantified objectively with such a level of sensitivity as has been reported with IENFD. Recent advances include an expansion of the skin punch biopsy technique to evaluate larger myelinated fibers and mechanoreceptors, and recent work has also focused on additional methods of quantifying dermal fibers and densely innervated autonomic structures. This review discusses current work using skin biopsy for the pathologic analysis of peripheral nerve fibers in neuropathy of various causes as well as its use in clinical trials. PMID:23250768

Myers, M. Iliza; Peltier, Amanda C.

2013-01-01

20

Ulnar nerve palsy-like motor and sensory loss caused by a small cortical infarct.  

PubMed

A 56-year-old man with a small infarct in the left precentral knob area induced both motor and sensory impairments that were similar to right ulnar nerve palsy. The only difference from ulnar nerve palsy was that the patient showed sensory disturbance not only on the ulnar side but also on the radial side of the right ring finger. PMID:21440458

Ueno, Tatsuya; Tomiyama, Masahiko; Haga, Rie; Nishijima, Haruo; Kon, Tomoya; Funamizu, Yukihisa; Miki, Yasuo; Arai, Akira; Suzuki, Chieko; Baba, Masayuki

2012-11-01

21

Photostimulation of sensory neurons of the rat vagus nerve  

NASA Astrophysics Data System (ADS)

We studied the effect of infrared (IR) stimulation on rat sensory neurons. Primary sensory neurons were prepared by enzymatic dissociation of the inferior (or "nodose") ganglia from the vagus nerves of rats. The 1.85-?m output of a diode laser, delivered through a 200-?m silica fiber, was used for photostimulation. Nodose neurons express the vanilloid receptor, TRPV1, which is a non-selective cation channel that opens in response to significant temperature jumps above 37 C. Opening TRPV1 channels allows entry of cations, including calcium (Ca 2+), into the cell to cause membrane depolarization. Therefore, to monitor TRPV1 activation consequent to photostimulation, we used fura-2, a fluorescent Ca 2+ indicator, to monitor the rise in intracellular Ca 2+ concentration ([Ca 2+]i). Brief trains of 2-msec IR pulses activated TRPV1 rapidly and reversibly, as evidenced by transient rises in [Ca 2+]i (referred to as Ca 2+ transients). Consistent with the Ca 2+ transients arising from influx of Ca 2+, identical photostimulation failed to evoke Ca 2+ responses in the absence of extracellular Ca 2+. Furthermore, the photo-induced Ca 2+ signals were abolished by capsazepine, a specific blocker of TRPV1, indicating that the responses were indeed mediated by TRPV1. We discuss the feasibility of using focal IR stimulation to probe neuronal circuit properties in intact neural tissue, and compare IR stimulation with another photostimulation technique-focal photolytic release of "caged" molecules.

Rhee, Albert Y.; Li, Gong; Wells, Jonathon; Kao, Joseph P. Y.

2008-02-01

22

Arnold’s nerve cough reflex: evidence for chronic cough as a sensory vagal neuropathy  

PubMed Central

Arnold’s nerve ear-cough reflex is recognised to occur uncommonly in patients with chronic cough. In these patients, mechanical stimulation of the external auditory meatus can activate the auricular branch of the vagus nerve (Arnold’s nerve) and evoke reflex cough. This is an example of hypersensitivity of vagal afferent nerves, and there is now an increasing recognition that many cases of refractory or idiopathic cough may be due to a sensory neuropathy of the vagus nerve. We present two cases where the cause of refractory chronic cough was due to sensory neuropathy associated with ear-cough reflex hypersensitivity. In both cases, the cough as well as the Arnold’s nerve reflex hypersensitivity were successfully treated with gabapentin, a treatment that has previously been shown to be effective in the treatment of cough due to sensory laryngeal neuropathy (SLN). PMID:25383210

Gibson, Peter G.; Birring, Surinder S.

2014-01-01

23

Schwann Cells Seeded in Acellular Nerve Grafts Improve Functional Recovery  

PubMed Central

Introduction This study evaluated whether Schwann cells (SCs) from different nerve sources transplanted into cold-preserved acellular nerve grafts (CP-ANGs) would improve functional regeneration compared to nerve isografts. Methods SCs isolated and expanded from motor and sensory branches of rat femoral and sciatic nerves were seeded into 14mm CP-ANGs. Growth factor expression, axonal regeneration, and functional recovery were evaluated in a14 mm rat sciatic injury model and compared to isografts. Results At 14 days, motor or sensory-derived SCs increased expression of growth factors in CP-ANGs versus isografts. After 42 days, histomorphometric analysis found CP-ANGs with SCs and isografts had similar numbers of regenerating nerve fibers. At 84 days, muscle force generation was similar for CP-ANGs with SCs and isografts. SC source did not affect nerve fiber counts or muscle force generation. Discussion SCs transplanted into CP-ANGs increase functional regeneration to isograft levels; however SC nerve source did not have an effect. PMID:23625513

Jesuraj, Nithya J.; Santosa, Katherine B.; MacEwan, Matthew R.; Moore, Amy M.; Kasukurthi, Rahul; Ray, Wilson Z.; Flagg, Eric R.; Hunter, Daniel A.; Borschel, Gregory H.; Johnson, Philip J.; Mackinnon, Susan E.; Sakiyama-Elbert, Shelly E.

2014-01-01

24

Changes in sensory activity of ocular surface sensory nerves during allergic keratoconjunctivitis.  

PubMed

Peripheral neural mechanisms underlying the sensations of irritation, discomfort, and itch accompanying the eye allergic response have not been hitherto analyzed. We explored this question recording the changes in the electrical activity of corneoconjunctival sensory nerve fibers of the guinea pig after an ocular allergic challenge. Sensitization was produced by i.p. ovalbumin followed by repeated application in the eye of 10% ovalbumin on days 14 to 18. Blinking and tearing rate were measured. Spontaneous and stimulus-evoked (mechanical, thermal, chemical) impulse activity was recorded from mechanonociceptor, polymodal nociceptor and cold corneoscleral sensory afferent fibers. After a single (day 14) or repeated daily exposures to the allergen during the following 3 to 4days, tearing and blinking rate increased significantly. Also, sensitization was observed in mechanonociceptors (transient reduction of mechanical threshold only on day 14) and in polymodal nociceptors (sustained enhancement of the impulse response to acidic stimulation). In contrast, cold thermoreceptors showed a significant decrease in basal ongoing activity and in the response to cooling. Treatment with the TRPV1 and TRPA1 blockers capsazepine and HC-030031 reversed the augmented blinking. Only capsazepine attenuated tearing rate increase and sensitization of the polymodal nociceptors response to CO2. Capsazepine also prevented the decrease in cold thermoreceptor activity caused by the allergic challenge. We conclude that changes in nerve impulse activity accompanying the ocular allergic response, primarily mediated by activation of nociceptor's TRPV1 and to a lesser degree by activation of TRPA1 channels, explain the eye discomfort sensations accompanying allergic episodes. PMID:23867735

Acosta, M Carmen; Luna, Carolina; Quirce, Susana; Belmonte, Carlos; Gallar, Juana

2013-11-01

25

Effects of Ozone on Epithelium and Sensory Nerves in the Bronchial Mucosa of Healthy Humans  

Microsoft Academic Search

Neuropeptides released from sensory nerves during inflammation have potent effects on broncho- motor tone, airway secretion, and inflammatory cells. We investigated the effects of ozone on sen- sory nerves by exposing 12 healthy, nonsmoking subjects to 0.2 ppm ozone and filtered air (FA) for 2 h on separate occasions, with intermittent exercise and rest. Spirometry was performed at baseline and

MAMIDIPUDI THIRUMALA KRISHNA; DAVID SPRINGALL; QING-HAI MENG; NICHOLAS WITHERS; DOMINIC MACLEOD; GIANLUCA BISCIONE; ANTHONY FREW; JULIA POLAK; STEPHEN HOLGATE

26

Myelinated sensory and alpha motor axon regeneration in peripheral nerve neuromas  

NASA Technical Reports Server (NTRS)

Histochemical staining for carbonic anhydrase and cholinesterase (CE) activities was used to analyze sensory and motor axon regeneration, respectively, during neuroma formation in transected and tube-encapsulated peripheral nerves. Median-ulnar and sciatic nerves in the rodent model permitted testing whether a 4 cm greater distance of the motor neuron soma from axotomy site or intrinsic differences between motor and sensory neurons influenced regeneration and neuroma formation 10, 30, and 90 days later. Ventral root radiculotomy confirmed that CE-stained axons were 97% alpha motor axons. Distance significantly delayed axon regeneration. When distance was negligible, sensory axons grew out sooner than motor axons, but motor axons regenerated to a greater quantity. These results indicate regeneration differences between axon subtypes and suggest more extensive branching of motor axons within the neuroma. Thus, both distance from injury site to soma and inherent motor and sensory differences should be considered in peripheral nerve repair strategies.

Macias, M. Y.; Lehman, C. T.; Sanger, J. R.; Riley, D. A.

1998-01-01

27

Hydrophilic Polymers Enhance Early Functional Outcomes after Nerve Autografting  

PubMed Central

Background Approximately 12% of operations for traumatic neuropathy are for patients with segmental nerve loss and less than 50% of these injuries obtain meaningful functional recovery. Polyethylene glycol (PEG) therapy has been shown to improve functional outcomes after nerve severance and we hypothesized this therapy could also benefit nerve autografting. Methods A segmental rat sciatic nerve injury model was used, whereby a 0.5 cm defect was repaired with an autograft using microsurgery. Experimental animals were treated with solutions containing methylene blue (MB) and PEG; control animals did not receive PEG. Compound Actions Potentials (CAPs) were recorded before nerve transection, after solution therapy, and at 72 hours postoperatively. The animals underwent behavioral testing at 24 and 72 hours postoperatively. After sacrifice, nerves were fixed, sectioned, and immunostained to allow for quantitative morphometric analysis. Results The introduction of hydrophilic polymers greatly improved morphological and functional recovery of rat sciatic axons at 1–3 days following nerve autografting. PEG therapy restored CAPs in all animals and CAPs were still present 72 hours postoperatively. No CAPS were detectable in control animals. Footfall asymmetry scores and sciatic functional index scores were significantly improved for PEG therapy group at all time points (p <0.05 and p<0.001; p <0.001 and p <0.01). Sensory and motor axon counts were increased distally in nerves treated with PEG compared to control (p = 0.0189 and p = 0.0032). Conclusions PEG therapy improves early physiologic function, behavioral outcomes, and distal axonal density after nerve autografting. PMID:22521220

Sexton, Kevin W.; Pollins, Alonda C.; Cardwell, Nancy L.; Del Corral, Gabriel A.; Bittner, George D.; Shack, R. Bruce; Nanney, Lillian B.; Thayer, Wesley P.

2014-01-01

28

Sensory nerve conduction and nociception in the equine lower forelimb during perineural bupivacaine infusion along the palmar nerves  

PubMed Central

The purpose of this investigation was to study lateral palmar nerve (LPN) and medial palmar nerve (MPN) morphology and determine nociception and sensory nerve conduction velocity (SNCV) following placement of continuous peripheral nerve block (CPNB) catheters along LPN and MPN with subsequent bupivacaine (BUP) infusion. Myelinated nerve fiber distribution in LPN and MPN was examined after harvesting nerve specimens in 3 anesthetized horses and processing them for morphometric analysis. In 5 sedated horses, CPNB catheters were placed along each PN in both forelimbs. Horses then received in one forelimb 3 mL 0.125% BUP containing epinephrine 1:200 000 and 0.04% NaHCO3 per catheter site followed by 2 mL/h infusion over a 6-day period, while in the other forelimb equal amounts of saline (SAL) solution were administered. The hoof withdrawal response (HWR) threshold during pressure loading of the area above the dorsal coronary band was determined daily in both forelimbs. On day 6 SNCV was measured under general anesthesia of horses in each limb’s LPN and MPN to detect nerve injury, followed by CPNB catheter removal. The SNCV was also recorded in 2 anesthetized non-instrumented horses (sham controls). In both LPN and MPN myelinated fiber distributions were bimodal. The fraction of large fibers (>7 ?m) was greater in the MPN than LPN (P < 0.05). Presence of CPNB catheters and SAL administration did neither affect measured HWR thresholds nor SNCVs, whereas BUP infusion suppressed HWRs. In conclusion, CPNB with 0.125% BUP provides pronounced analgesia by inhibiting sensory nerve conduction in the distal equine forelimb. PMID:21197231

Zarucco, Laura; Driessen, Bernd; Scandella, Massimiliano; Cozzi, Francesca; Cantile, Carlo

2010-01-01

29

TRPA1 induced in sensory neurons contributes to cold hyperalgesia after inflammation and nerve injury  

PubMed Central

Cold hyperalgesia is a well-documented symptom of inflammatory and neuropathic pain; however, the underlying mechanisms of this enhanced sensitivity to cold are poorly understood. A subset of transient receptor potential (TRP) channels mediates thermosensation and is expressed in sensory tissues, such as nociceptors and skin. Here we report that the pharmacological blockade of TRPA1 in primary sensory neurons reversed cold hyperalgesia caused by inflammation and nerve injury. Inflammation and nerve injury increased TRPA1, but not TRPM8, expression in tyrosine kinase A–expressing dorsal root ganglion (DRG) neurons. Intrathecal administration of anti–nerve growth factor (anti-NGF), p38 MAPK inhibitor, or TRPA1 antisense oligodeoxynucleotide decreased the induction of TRPA1 and suppressed inflammation- and nerve injury–induced cold hyperalgesia. Conversely, intrathecal injection of NGF, but not glial cell line–derived neurotrophic factor, increased TRPA1 in DRG neurons through the p38 MAPK pathway. Together, these results demonstrate that an NGF-induced TRPA1 increase in sensory neurons via p38 activation is necessary for cold hyperalgesia. Thus, blocking TRPA1 in sensory neurons might provide a fruitful strategy for treating cold hyperalgesia caused by inflammation and nerve damage. PMID:16110328

Obata, Koichi; Katsura, Hirokazu; Mizushima, Toshiyuki; Yamanaka, Hiroki; Kobayashi, Kimiko; Dai, Yi; Fukuoka, Tetsuo; Tokunaga, Atsushi; Tominaga, Makoto; Noguchi, Koichi

2005-01-01

30

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

PubMed Central

Background 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. Methods 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. Results 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 and Block Test score improved through SENS intervention and was partly maintained after SENS was removed, until at least 7 months after the intervention. The sensory test score, however, showed no recovery after intervention. Conclusions We conclude that the proposed system would be useful in the rehabilitation of patients with sensory loss. PMID:23764012

2013-01-01

31

Video-Gait Analysis of Functional Recovery of Nerve Repaired with Chitosan Nerve Guides  

E-print Network

Video-Gait Analysis of Functional Recovery of Nerve Repaired with Chitosan Nerve Guides MINAL PATEL assessment of functional sciatic nerve recovery treated with chitosan nerve guides. We used video to functional nerve recovery. The chitosan group showed increased functional improvement compared to the control

VandeVord, Pamela

32

Various types of total laparoscopic nerve-sparing radical hysterectomies and their effects on bladder function  

PubMed Central

Objective This study was conducted to ascertain the correlation between preserved pelvic nerve networks and bladder function after laparoscopic nerve-sparing radical hysterectomy. Methods Between 2009 and 2011, 53 patients underwent total laparoscopic radical hysterectomies. They were categorized into groups A, B, and C based on the status of preserved pelvic nerve networks: complete preservation of the pelvic nerve plexus (group A, 27 cases); partial preservation (group B, 13 cases); and complete sacrifice (group C, 13 cases). To evaluate bladder function, urodynamic studies were conducted preoperatively and postoperatively at 1, 3, 6, and 12 months after surgery. Results No significant difference in sensory function was found between groups A and B. However, the sensory function of group C was significantly lower than that of the other groups. Group A had significantly better motor function than groups B and C. No significant difference in motor function was found between groups B and C. Results showed that the sensory nerve is distributed predominantly at the dorsal half of the pelvic nerve networks, but the motor nerve is predominantly distributed at the ventral half. Conclusion Various types of total laparoscopic nerve-sparing radical hysterectomies can be tailored to patients with cervical carcinomas. PMID:25045432

Fujiwara, Kazuko; Ebisawa, Keiko; Hada, Tomonori; Ota, Yoshiaki; Andou, Masaaki

2014-01-01

33

Systemic acetyl- l -carnitine eliminates sensory neuronal loss after peripheral axotomy: a new clinical approach in the management of peripheral nerve trauma  

Microsoft Academic Search

Several hundred thousand peripheral nerve injuries occur each year in Europe alone. Largely due to the death of around 40%\\u000a of primary sensory neurons, sensory outcome remains disappointingly poor despite considerable advances in surgical technique;\\u000a yet no clinical therapies currently exist to prevent this neuronal death. Acetyl-l-carnitine (ALCAR) is a physiological peptide with roles in mitochondrial bioenergetic function, which may

Andrew McKay Hart; Mikael Wiberg; Mike Youle; Giorgio Terenghi

2002-01-01

34

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

SciTech Connect

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 promising strategy for peripheral nerve repair.

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

2013-10-18

35

Heightened motor and sensory (mirror-touch) referral induced by nerve block or topical anesthetic.  

PubMed

Mirror neurons allow us to covertly simulate the sensation and movement of others. If mirror neurons are sensory and motor neurons, why do we not actually feel this simulation- like "mirror-touch synesthetes"? Might afferent sensation normally inhibit mirror representations from reaching consciousness? We and others have reported heightened sensory referral to phantom limbs and temporarily anesthetized arms. These patients, however, had experienced illness or injury of the deafferented limb. In the current study we observe heightened sensory and motor referral to the face after unilateral nerve block for routine dental procedures. We also obtain double-blind, quantitative evidence of heightened sensory referral in healthy participants completing a mirror-touch confusion task after topical anesthetic cream is applied. We suggest that sensory and motor feedback exist in dynamic equilibrium with mirror representations; as feedback is reduced, the brain draws more upon visual information to determine- perhaps in a Bayesian manner- what to feel. PMID:23791606

Case, Laura K; Gosavi, Radhika; Ramachandran, Vilayanur S

2013-08-01

36

Capsaicin Combined with Local Anesthetics Preferentially Prolongs Sensory/Nociceptive Block in Rat Sciatic Nerve  

PubMed Central

Background Transient receptor potential vanilloid 1 channels integrate nociceptive stimuli and are predominantly expressed by unmyelinated C-fiber nociceptors, but not low-threshold mechanoreceptive sensory or motor fibers. A recent report showed that the transient receptor potential vanilloid 1 channel agonist capsaicin allows a hydrophilic quaternary ammonium derivative of lidocaine, QX-314, to selectively block C fibers without motor block. The authors tested whether a similar differential block would be produced using amphipathicN-methyl amitriptyline, amitriptyline, bupivacaine, or lidocaine, either alone or together with 0.05% capsaicin, in a rat sciatic nerve block model. Methods Rats (n = 8/group) were anesthetized with sevoflurane, and 0.2 ml of drug was injected either alone or with capsaicin (simultaneously or 10 min later) next to the sciatic nerve in the sciatic notch. Motor function was assessed by the extensor postural thrust. Nociception was evaluated by the nocifensive withdrawal reflex and vocalization evoked by pinch of a skin fold over the lateral metatarsus (cutaneous pain) with a serrated forceps. Results N-Methyl amitriptyline, amitriptyline, bupivacaine, or lidocaine, followed by injection of capsaicin 10 min later, each elicited a predominantly nociceptive-specific blockade. In comparison, simultaneous application of each local anesthetic with capsaicin did not elicit a clinically significant differential block, with the exception of N-methyl amitriptyline. Conclusions Both tertiary amine local anesthetics and their quaternary ammonium derivatives can elicit a predominantly sensory/nociceptor selective block when followed by injection of capsaicin. The combined application of transient receptor potential vanilloid 1 channel agonists and various local anesthetics or their quaternary ammonium derivatives is an appealing strategy to achieve a long-lasting differential block in regional analgesia. PMID:18946300

Binshtok, Alexander M.; Wang, Chi-Fei; Hevelone, Nathanael D.; Bean, Bruce P.; Woolf, Clifford J.; Wang, Ging Kuo

2009-01-01

37

Sensory nerve terminal mitochondrial dysfunction induces hyperexcitability in airway nociceptors via protein kinase C.  

PubMed

Airway sensory nerve excitability is a key determinant of respiratory disease-associated reflexes and sensations such as cough and dyspnea. Inflammatory signaling modulates mitochondrial function and produces reactive oxygen species (ROS). Peripheral terminals of sensory nerves are densely packed with mitochondria; thus, we hypothesized that mitochondrial modulation would alter neuronal excitability. We recorded action potential firing from the terminals of individual bronchopulmonary C-fibers using a mouse ex vivo lung-vagal ganglia preparation. C-fibers were characterized as nociceptors or non-nociceptors based upon conduction velocity and response to transient receptor potential (TRP) channel agonists. Antimycin A (mitochondrial complex III Qi site inhibitor) had no effect on the excitability of non-nociceptors. However, antimycin A increased excitability in nociceptive C-fibers, decreasing the mechanical threshold by 50% and increasing the action potential firing elicited by a P2X2/3 agonist to 270% of control. Antimycin A-induced nociceptor hyperexcitability was independent of TRP ankyrin 1 or TRP vanilloid 1 channels. Blocking mitochondrial ATP production with oligomycin or myxothiazol had no effect on excitability. Antimycin A-induced hyperexcitability was dependent on mitochondrial ROS and was blocked by intracellular antioxidants. ROS are known to activate protein kinase C (PKC). Antimycin A-induced hyperexcitability was inhibited by the PKC inhibitor bisindolylmaleimide (BIM) I, but not by its inactive analog BIM V. In dissociated vagal neurons, antimycin A caused ROS-dependent PKC translocation to the membrane. Finally, H2O2 also induced PKC-dependent nociceptive C-fiber hyperexcitability and PKC translocation. In conclusion, ROS evoked by mitochondrial dysfunction caused nociceptor hyperexcitability via the translocation and activation of PKC. PMID:24642367

Hadley, Stephen H; Bahia, Parmvir K; Taylor-Clark, Thomas E

2014-06-01

38

Mustard oils and cannabinoids excite sensory nerve fibres through the TRP channel ANKTM1  

Microsoft Academic Search

Wasabi, horseradish and mustard owe their pungency to isothiocyanate compounds. Topical application of mustard oil (allyl isothiocyanate) to the skin activates underlying sensory nerve endings, thereby producing pain, inflammation and robust hypersensitivity to thermal and mechanical stimuli. Despite their widespread use in both the kitchen and the laboratory, the molecular mechanism through which isothiocyanates mediate their effects remains unknown. Here

Sven-Eric Jordt; Diana M. Bautista; Huai-hu Chuang; David D. McKemy; Peter M. Zygmunt; Edward D. Högestätt; Ian D. Meng; David Julius

2004-01-01

39

Precision pinch performance in patients with sensory deficits of the median nerve at the carpal tunnel.  

PubMed

To investigate how sensory symptoms impact the motor control of hands, in this study we examined the differences in conventional sensibility assessments and pinch force control in the pinch-holding-up activity (PHUA) test between carpal tunnel syndrome (CTS) patients and healthy controls. CTS patients (n = 82) with 122 affected hands and an equal number of control subjects were recruited to participate in the threshold, discrimination, and PHUA tests. The patients showed significantly poorer hand sensibility and lower efficiency of force adjustment in the PHUA test as compared with the control subjects. Baseline pinch strength and the percentage of maximal pinch strength for the PHUA were significantly higher for the subgroup of sensory nerve action potential (SNAP) of <16 ?V than for the subgroup of SNAP of ?16 ?V. Using a PHUA perspective to analyze the efficiency of force-adjustment could assist the clinical detection of sensory nerve dysfunction. PMID:24496877

Yen, Wei-Jang; Kuo, Yao-Lung; Kuo, Li-Chieh; Chen, Shu-Min; Kuan, Ta-Shen; Hsu, Hsiu-Yun

2014-01-01

40

Changes induced by peripheral nerve injury in the morphology and nanomechanics of sensory neurons  

NASA Astrophysics Data System (ADS)

Peripheral nerve injury in vivo promotes a regenerative growth in vitro characterized by an improved neurite regrowth. Knowledge of the conditioning injury effects on both morphology and mechanical properties of live sensory neurons could be instrumental to understand the cellular and molecular mechanisms leading to this regenerative growth. In the present study, we use differential interference contrast microscopy, fluorescence microscopy and atomic force microscopy (AFM) to show that conditioned axotomy, induced by sciatic nerve injury, does not increase somatic size of sensory neurons from adult mice lumbar dorsal root ganglia but promotes the appearance of longer and larger neurites and growth cones. AFM on live neurons is also employed to investigate changes in morphology and membrane mechanical properties of somas of conditioned neurons following sciatic nerve injury. Mechanical analysis of the soma allows distinguishing neurons having a regenerative growth from control ones, although they show similar shapes and sizes.

Benzina, Ouafa; Szabo, Vivien; Lucas, Olivier; Saab, Marie-belle; Cloitre, Thierry; Scamps, Frédérique; Gergely, Csilla; Martin, Marta

2013-06-01

41

Aging profoundly delays functional recovery from gustatory nerve injury  

PubMed Central

The peripheral taste system remains plastic during adulthood. Sectioning the chorda tympani (CT) nerve, which sends sensory information from the anterior tongue to the CNS, causes degeneration of distal fibers and target taste buds. However, taste function is restored after about 40 days in young adult rodents. We tested whether aging impacts the reappearance of neural responses after unilateral CT nerve injury. Taste bud regeneration was minimal at day 50–65 after denervation, and most aged animals died before functional recovery could be assessed. A subset (n=3/5) of old rats exhibited normal CT responses at day 85 post-sectioning, suggesting the potential for efficient recovery. The aged taste system is fairly resilient to sensory receptor loss and major functional changes in normal aging. However, injury to the taste system reveals a surprising vulnerability in old rodents. The gustatory system provides an excellent model to study mechanisms underlying delayed recovery from peripheral nerve injury. Strategies to accelerate recovery and restore normal function will be of interest as the elderly population continues to grow. PMID:22387273

He, Lianying; Yadgarov, Arkadiy; Sharif, Shan; McCluskey, Lynnette Phillips

2012-01-01

42

Low-level laser treatment improves longstanding sensory aberrations in the inferior alveolar nerve following surgical trauma  

NASA Astrophysics Data System (ADS)

The incidence of inferior alveolar nerve (IAN) damage following removal of 3rd molar teeth or saggital split osteotomy has been reported as high as up to 5.5% and 100% respectively. Sensory aberrations in the IAN persisting for longer than 6 months leave some degree of permanent defect. Low level laser treatment (LLL) has a reported beneficial effect on regeneration of traumatically injured nerves. The purpose of this double blind clinical trial was to examine the effects of LLL using a GaAlAs laser (820 nm, Ronvig, Denmark) on touch and temperature sensory perception following a longstanding post surgical IAN injury. Thirteen patients were divided into two groups, one of which received real LLL (4 by 6 J per treatment along the distribution of the IAN to a total of 20 treatments during a time period between 36 - 69 days) and the other equivalent placebo LLL. The degree of mechanoreceptor injury as assessed by Semmes Weinstein Monofilaments (North Coast Medical, USA) were comparable in the two groups prior to treatment (p equals 0.9). Subsequent to LLL the real laser treatment group showed a significant improvement in mechanoreceptor sensory testing (p equals 0.01) as manifested by a decrease in load threshold (g) necessary to elicit a response from the most damaged area. The placebo LLL group showed no significant improvement, In addition, the real LLL group reported a subjective improvement in sensory function too. The degree of thermal sensitivity disability as assessed using a thermotester (Philips, Sweden) was comparable between the two groups prior to LLL p equals 0.5). However, there was no significant improvement in thermal sensitivity post LLL for either the real or placebo laser treated groups. In conclusion, GaAlAs LLL can improve mechanoreceptor perception in longstanding sensory aberration in the IAN.

Khullar, Shelley M.; Brodin, P.; Barkvoll, P.; Haanoes, H. R.

1996-01-01

43

Amplitude of sensory nerve action potential in early stage diabetic peripheral neuropathy: an analysis of 500 cases  

PubMed Central

Early diagnosis of diabetic peripheral neuropathy is important for the successful treatment of diabetes mellitus. In the present study, we recruited 500 diabetic patients from the Fourth Affiliated Hospital of Kunming Medical University in China from June 2008 to September 2013: 221 cases showed symptoms of peripheral neuropathy (symptomatic group) and 279 cases had no symptoms of peripheral impairment (asymptomatic group). One hundred healthy control subjects were also recruited. Nerve conduction studies revealed that distal motor latency was longer, sensory nerve conduction velocity was slower, and sensory nerve action potential and amplitude of compound muscle action potential were significantly lower in the median, ulnar, posterior tibial and common peroneal nerve in the diabetic groups compared with control subjects. Moreover, the alterations were more obvious in patients with symptoms of peripheral neuropathy. Of the 500 diabetic patients, neural conduction abnormalities were detected in 358 cases (71.6%), among which impairment of the common peroneal nerve was most prominent. Sensory nerve abnormality was more obvious than motor nerve abnormality in the diabetic groups. The amplitude of sensory nerve action potential was the most sensitive measure of peripheral neuropathy. Our results reveal that varying degrees of nerve conduction changes are present in the early, asymptomatic stage of diabetic peripheral neuropathy. PMID:25221597

Zhang, Yunqian; Li, Jintao; Wang, Tingjuan; Wang, Jianlin

2014-01-01

44

Cough Sensors. III. Opioid and Cannabinoid Receptors on Vagal Sensory Nerves  

Microsoft Academic Search

Cough is a persistent symptom of many inflammatory airways' diseases. Cough is mediated by receptors sited on sensory nerves\\u000a and then through vagal afferent pathways, which terminate in the brainstem respiratory centre. Cough is often described as\\u000a an unmet clinical need. Opioids are the only prescription-based anti-tussives currently available in the UK. They possess\\u000a limited efficacy and exhibit serious unwanted

M. G. Belvisi; D. J. Hele

45

?? T cells infiltrating sensory nerve biopsies from patients with inflammatory neuropathy  

Microsoft Academic Search

Sensory nerve biopsy specimens from patients with Guillain Barré syndrome (GBS), chronic inflammatory demyelinating polyneuropathy\\u000a (CIDP), and controls consisting of other neuropathies, were examined in order to characterise the nature and intensity of\\u000a any inflammatory infiltrate. In order to establish whether ?? T cells were present in these infiltrates we examined the expression\\u000a of ?? and ?? T cell receptors

John Winer; Sharon Hughes; Joanne Cooper; Anne Ben-Smith; Caroline Savage

2002-01-01

46

Hyperglycemia- and neuropathy-induced changes in mitochondria within sensory nerves  

PubMed Central

Objective This study focused on altered mitochondrial dynamics as a potential mechanism for diabetic peripheral neuropathy (DPN). We employed both an in vitro sensory neuron model and an in situ analysis of human intraepidermal nerve fibers (IENFs) from cutaneous biopsies to measure alterations in the size distribution of mitochondria as a result of hyperglycemia and diabetes, respectively. Methods Neurite- and nerve-specific mitochondrial signals within cultured rodent sensory neurons and human IENFs were measured by employing a three-dimensional visualization and quantification technique. Skin biopsies from distal thigh (DT) and distal leg (DL) were analyzed from three groups of patients; patients with diabetes and no DPN, patients with diabetes and confirmed DPN, and healthy controls. Results This analysis demonstrated an increase in mitochondria distributed within the neurites of cultured sensory neurons exposed to hyperglycemic conditions. Similar changes were observed within IENFs of the DT in DPN patients compared to controls. This change was represented by a significant shift in the size frequency distribution of mitochondria toward larger mitochondria volumes within DT nerves of DPN patients. There was a length-dependent difference in mitochondria within IENFs. Distal leg IENFs from control patients had a significant shift toward larger volumes of mitochondrial signal compared to DT IENFs. Interpretation The results of this study support the hypothesis that altered mitochondrial dynamics may contribute to DPN pathogenesis. Future studies will examine the potential mechanisms that are responsible for mitochondrial changes within IENFs and its effect on DPN pathogenesis. PMID:25493271

Hamid, Hussein S; Mervak, Colin M; Münch, Alexandra E; Robell, Nicholas J; Hayes, John M; Porzio, Michael T; Singleton, J Robinson; Smith, A Gordon; Feldman, Eva L; Lentz, Stephen I

2014-01-01

47

Sigma-1 receptor expression in sensory neurons and the effect of painful peripheral nerve injury  

PubMed Central

Background The sigma-1 receptor (?1R), an endoplasmic reticulum chaperone protein, is widely distributed and regulates numerous intracellular processes in neurons. Nerve injury alters the structure and function of axotomized dorsal root ganglion (DRG) neurons, contributing to the development of pain. The ?1R is enriched in the spinal cord and modulates pain after peripheral nerve injury. However, ?1R expression in the DRG has not been studied. We therefore characterized ?1R expression in DRGs at baseline and following spinal nerve ligation (SNL) in rats. Results Immunohistochemical (IHC) studies in DRG sections show ?1R in both neuronal somata and satellite glial cells. The punctate distribution of ?1R in the neuronal cytoplasm suggests expression in the endoplasmic reticulum. When classified by neuronal size, large neurons (>1300 ?m) showed higher levels of ?1R staining than other groups (700-1300 ?m, <700 ?m). Comparing ?1R expression in neuronal groups characterized by expression of calcitonin gene-related peptide (CGRP), isolectin-B4 (IB4) and neurofilament-200 (NF-200), we found ?1R expression in all three neuronal subpopulations, with highest levels of ?1R expression in the NF-200 group. After SNL, lysates from L5 DRGs that contains axotomized neurons showed decreased ?1R protein but unaffected transcript level, compared with Control DRGs. IHC images also showed decreased ?1R protein expression, in SNL L5 DRGs, and to a lesser extent in the neighboring SNL L4 DRGs. Neurons labeled by CGRP and NF-200 showed decreased ?1R expression in L5 and, to a lesser extent, L4 DRGs. In IB4-labeled neurons, ?1R expression decreased only in axotomized L5 DRGs. Satellite cells also showed decreased ?1R expression in L5 DRGs after SNL. Conclusions Our data show that ?1R is present in both sensory neurons and satellite cells in rat DRGs. Expression of ?1R is down-regulated in axotomized neurons as well as in their accompanying satellite glial cells, while neighboring uninjured neurons show a lesser down-regulation. Therefore, elevated ?1R expression in neuropathic pain is not an explanation for pain relief after ?1R blockade. This implies that increased levels of endogenous ?1R agonists may play a role, and diminished neuroprotection from loss of glial ?1R may be a contributing factor. PMID:24015960

2013-01-01

48

Effects of Acute Organophosphorus Poisoning on Function of Peripheral Nerves: A Cohort Study  

PubMed Central

Background Following acute organophosphorus (OP) poisoning patients complain of numbness without objective sensory abnormalities or other features of OP induced delayed polyneuropathy. The aim of this study was to measure peripheral nerve function after acute exposure to OP. Methods A cohort study was conducted with age, gender and occupation matched controls. Motor nerve conduction velocity (MNCV), amplitude and area of compound muscle action potential (CMAP), sensory nerve conduction velocity (SNCV), F- waves and electromyography (EMG) on the deltoid and the first dorsal interosseous muscles on the dominant side were performed, following acute OP poisoning. All neurophysiological assessments except EMG were performed on the controls. Assessments were performed on the day of discharge from the hospital (the first assessment) and six weeks (the second assessment) after the exposure. The controls were assessed only once. Results There were 70 patients (50 males) and 70 controls. Fifty-three patients attended for the second assessment. In the first assessment MNCV of all the motor nerves examined, CMAP amplitude and SNCV of ulnar nerve, median and ulnar F-wave occurrence in the patients were significantly reduced compared to the controls. In the second assessment significant reduction was found in SNCV of both sensory nerves examined, MNCV of ulnar nerve, CMAP amplitude of common peroneal nerve, F-wave occurrence of median and ulnar nerves. No abnormalities were detected in the patients when compared to the standard cut-off values of nerve conduction studies except F-wave occurrence. EMG studies did not show any abnormality. Conclusion There was no strong evidence of irreversible peripheral nerve damage following acute OP poisoning, however further studies are required. PMID:23185328

Jayasinghe, Sudheera S.; Pathirana, Kithsiri D.; Buckley, Nick A.

2012-01-01

49

Sensory Sensitivities and Performance on Sensory Perceptual Tasks in High-Functioning Individuals with Autism  

ERIC Educational Resources Information Center

Most reports of sensory symptoms in autism are second hand or observational, and there is little evidence of a neurological basis. Sixty individuals with high-functioning autism and 61 matched typical participants were administered a sensory questionnaire and neuropsychological tests of elementary and higher cortical sensory perception. Thirty-two…

Minshew, Nancy J.; Hobson, Jessica A.

2008-01-01

50

Sensory and sympathetic nerve fibers undergo sprouting and neuroma formation in the painful arthritic joint of geriatric mice  

PubMed Central

Introduction Although the prevalence of arthritis dramatically increases with age, the great majority of preclinical studies concerning the mechanisms that drive arthritic joint pain have been performed in young animals. One mechanism hypothesized to contribute to arthritic pain is ectopic nerve sprouting; however, neuroplasticity is generally thought to be greater in young versus old nerves. Here we explore whether sensory and sympathetic nerve fibers can undergo a significant ectopic nerve remodeling in the painful arthritic knee joint of geriatric mice. Methods Vehicle (saline) or complete Freund's adjuvant (CFA) was injected into the knee joint of 27- to 29-month-old female mice. Pain behaviors, macrophage infiltration, neovascularization, and the sprouting of sensory and sympathetic nerve fibers were then assessed 28 days later, when significant knee-joint pain was present. Knee joints were processed for immunohistochemistry by using antibodies raised against CD68 (monocytes/macrophages), PECAM (endothelial cells), calcitonin gene-related peptide (CGRP; sensory nerve fibers), neurofilament 200 kDa (NF200; sensory nerve fibers), tyrosine hydroxylase (TH; sympathetic nerve fibers), and growth-associated protein 43 (GAP43; nerve fibers undergoing sprouting). Results At 4 weeks after initial injection, CFA-injected mice displayed robust pain-related behaviors (which included flinching, guarding, impaired limb use, and reduced weight bearing), whereas animals injected with vehicle alone displayed no significant pain-related behaviors. Similarly, in the CFA-injected knee joint, but not in the vehicle-injected knee joint, a remarkable increase was noted in the number of CD68+ macrophages, density of PECAM+ blood vessels, and density and formation of neuroma-like structures by CGRP+, NF200+, and TH+ nerve fibers in the synovium and periosteum. Conclusions Sensory and sympathetic nerve fibers that innervate the aged knee joint clearly maintain the capacity for robust nerve sprouting and formation of neuroma-like structures after inflammation/injury. Understanding the factors that drive this neuroplasticity, whether this pathologic reorganization of nerve fibers contributes to chronic joint pain, and how the phenotype of sensory and sympathetic nerves changes with age may provide pharmacologic insight and targets for better controlling aging-related joint pain. PMID:22548760

2012-01-01

51

Secretion of Growth Hormone in Response to Muscle Sensory Nerve Stimulation  

NASA Technical Reports Server (NTRS)

Growth hormone (GH) secretion is stimulated by aerobic and resistive exercise and inhibited by exposure to actual or simulated (bedrest, hindlimb suspension) microgravity. Moreover, hypothalamic growth hormone-releasing factor (GRF) and preproGRF mRNA are markedly decreased in spaceflight rats. These observations suggest that reduced sensory input from inactive muscles may contribute to the reduced secretion of GH seen in "0 G". Thus, the aim of this study was to determine the effect of muscle sensory nerve stimulation on secretion of GH. Fed male Wistar rats (304 +/- 23 g) were anesthetized (pentobarbital) and the right peroneal (Pe), tibial (T), and sural (S) nerves were cut. Electrical stimulation of the distal (D) or proximal (P) ends of the nerves was implemented for 15 min. to mimic the EMG activity patterns of ankle extensor muscles of a rat walking 1.5 mph. The rats were bled by cardiac puncture and their anterior pituitaries collected. Pituitary and plasma bioactive (BGH) and immunoactive (IGH) GH were measured by bioassay and RIA.

Grindeland, Richard E.; Roy, R. R.; Edgerton, V. R.; Gosselink, K. L.; Grossman, E. J.; Sawchenko, P. E.; Wade, Charles E. (Technical Monitor)

1994-01-01

52

Cutaneous sensory nerve as a substitute for auditory nerve in solving deaf-mutes’ hearing problem: an innovation in multi-channel-array skin-hearing technology  

PubMed Central

The current use of hearing aids and artificial cochleas for deaf-mute individuals depends on their auditory nerve. Skin-hearing technology, a patented system developed by our group, uses a cutaneous sensory nerve to substitute for the auditory nerve to help deaf-mutes to hear sound. This paper introduces a new solution, multi-channel-array skin-hearing technology, to solve the problem of speech discrimination. Based on the filtering principle of hair cells, external voice signals at different frequencies are converted to current signals at corresponding frequencies using electronic multi-channel bandpass filtering technology. Different positions on the skin can be stimulated by the electrode array, allowing the perception and discrimination of external speech signals to be determined by the skin response to the current signals. Through voice frequency analysis, the frequency range of the band-pass filter can also be determined. These findings demonstrate that the sensory nerves in the skin can help to transfer the voice signal and to distinguish the speech signal, suggesting that the skin sensory nerves are good candidates for the replacement of the auditory nerve in addressing deaf-mutes’ hearing problems. Scientific hearing experiments can be more safely performed on the skin. Compared with the artificial cochlea, multi-channel-array skin-hearing aids have lower operation risk in use, are cheaper and are more easily popularized. PMID:25317171

Li, Jianwen; Li, Yan; Zhang, Ming; Ma, Weifang; Ma, Xuezong

2014-01-01

53

Renal sensory and sympathetic nerves reinnervate the kidney in a similar time-dependent fashion after renal denervation in rats  

PubMed Central

Efferent renal sympathetic nerves reinnervate the kidney after renal denervation in animals and humans. Therefore, the long-term reduction in arterial pressure following renal denervation in drug-resistant hypertensive patients has been attributed to lack of afferent renal sensory reinnervation. However, afferent sensory reinnervation of any organ, including the kidney, is an understudied question. Therefore, we analyzed the time course of sympathetic and sensory reinnervation at multiple time points (1, 4, and 5 days and 1, 2, 3, 4, 6, 9, and 12 wk) after renal denervation in normal Sprague-Dawley rats. Sympathetic and sensory innervation in the innervated and contralateral denervated kidney was determined as optical density (ImageJ) of the sympathetic and sensory nerves identified by immunohistochemistry using antibodies against markers for sympathetic nerves [neuropeptide Y (NPY) and tyrosine hydroxylase (TH)] and sensory nerves [substance P and calcitonin gene-related peptide (CGRP)]. In denervated kidneys, the optical density of NPY-immunoreactive (ir) fibers in the renal cortex and substance P-ir fibers in the pelvic wall was 6, 39, and 100% and 8, 47, and 100%, respectively, of that in the contralateral innervated kidney at 4 days, 4 wk, and 12 wk after denervation. Linear regression analysis of the optical density of the ratio of the denervated/innervated kidney versus time yielded similar intercept and slope values for NPY-ir, TH-ir, substance P-ir, and CGRP-ir fibers (all R2 > 0.76). In conclusion, in normotensive rats, reinnervation of the renal sensory nerves occurs over the same time course as reinnervation of the renal sympathetic nerves, both being complete at 9 to 12 wk following renal denervation. PMID:23408032

Mulder, Jan; Hökfelt, Tomas; Knuepfer, Mark M.

2013-01-01

54

Sensory sensitivities and performance on sensory perceptual tasks in high-functioning individuals with autism  

PubMed Central

Despite extensive reports of sensory symptoms in autism, there is little empirical support for their neurological basis. Sixty individuals with high-functioning autism and 61 matched typical comparison participants were administered a sensory questionnaire and standardized neuropsychological tests of elementary and higher cortical sensory perception. Thirty-two per cent of participants with autism endorsed more sensory sensitivity items than any of the participants in the comparison group. On the sensory perceptual exam, both groups made few errors on elementary sensory perception items. Controls made few errors on higher cortical sensory perception items, but 30% of the participants with autism made high numbers of errors, though there was no evidence of the neglect syndrome. There was little correlation between the sensory sensitivities and the sensory perceptual deficits, likely due to the low correspondence between the measures. These results support the common occurrence of disturbances in sensory experiences in high functioning individuals with autism based on first person report, and the presence of neurological abnormalities in higher cortical sensory perception. PMID:18302014

Minshew, Nancy J.; Hobson, Jessica A.

2011-01-01

55

Identifying motor and sensory myelinated axons in rabbit peripheral nerves by histochemical staining for carbonic anhydrase and cholinesterase activities  

NASA Technical Reports Server (NTRS)

Carbonic anhydrase (CA) and cholinesterase (CE) histochemical staining of rabbit spinal nerve roots and dorsal root ganglia demonstrated that among the reactive myeliated axons, with minor exceptions, sensory axons were CA positive and CE negative whereas motor axons were CA negative and CE positive. The high specificity was achieved by adjusting reaction conditions to stain subpopulations of myelinated axons selectively while leaving 50 percent or so unstained. Fixation with glutaraldehyde appeared necessary for achieving selectivity. Following sciatic nerve transection, the reciprocal staining pattern persisted in damaged axons and their regenerating processes which formed neuromas within the proximal nerve stump. Within the neuromas, CA-stained sensory processes were elaborated earlier and in greater numbers than CE-stained regenerating motor processes. The present results indicate that histochemical axon typing can be exploited to reveal heterogeneous responses of motor and sensory axons to injury.

Riley, Danny A.; Sanger, James R.; Matloub, Hani S.; Yousif, N. John; Bain, James L. W.

1988-01-01

56

Dual sensory-motor function for a molluskan statocyst network.  

PubMed

In mollusks, statocyst receptor cells (SRCs) interact with each other forming a neural network; their activity is determined by both the animal's orientation in the gravitational field and multimodal inputs. These two facts suggest that the function of the statocysts is not limited to sensing the animal's orientation. We studied the role of the statocysts in the organization of search motion during hunting behavior in the marine mollusk, Clione limacina. When hunting, Clione swims along a complex trajectory including numerous twists and turns confined within a definite space. Search-like behavior could be evoked pharmacologically by physostigmine; application of physostigmine to the isolated CNS produced "fictive search behavior" monitored by recordings from wing and tail nerves. Both in behavioral and in vitro experiments, we found that the statocysts are necessary for search behavior. The motor program typical of searching could not be produced after removing the statocysts. Simultaneous recordings from single SRCs and motor nerves showed that there was a correlation between the SRCs activity and search episodes. This correlation occurred even though the preparation was fixed and, therefore the sensory stimulus was constant. The excitation of individual SRCs could in some cases precede the beginning of search episodes. A biologically based model showed that, theoretically, the hunting search motor program could be generated by the statocyst receptor network due to its intrinsic dynamics. The results presented support for the idea that the statocysts are actively involved in the production of the motor program underlying search movements during hunting behavior. PMID:14507988

Levi, R; Varona, P; Arshavsky, Y I; Rabinovich, M I; Selverston, A I

2004-01-01

57

Capsaicin-sensitive sensory neurons regulate myocardial function and gene expression pattern of rat hearts: a DNA microarray study  

Microsoft Academic Search

We have previously shown that capsaicin-sensitive sensory nerves contribute to the regulation of normal cardiac function and to the development of cardiac adaptation to ischemic stress; however, the underlying molecular mechanisms remain unknown. Therefore, here we assessed cardiac functional alterations and relative gene expression changes by DNA microarray analysis of 6400 genes in rat hearts 7 days after the end

A. Zvara; Péter Bencsik; Gabriella Fodor; Tamás Csont; László Hackler; Mária Dux; Susanna Fürst; Gábor Jancsó; László G. Puskás; Péter Ferdinandy

2005-01-01

58

Abnormal cardiac nerve function in syndrome X  

Microsoft Academic Search

Syndrome X is likely to be caused by a dysfunction of small coronary arteries. Several authors suggested that an increased\\u000a adrenergic activity could be involved in the pathogenesis of syndrome X, but studies investigating this topic by indirect\\u000a methods led to conflicting results. p We directly investigated cardiac sympathetic nerve function in syndrome X by myocardial\\u000a radionuclide studies with123I-metaiodobenzylguanidine (MIBG).

Gaetano Antonio Lanza

1999-01-01

59

The effect of aging on the density of the sensory nerve fiber innervation of bone and acute skeletal pain  

PubMed Central

As humans age there is a decline in most sensory systems including vision, hearing, taste, smell, and tactile acuity. In contrast, the frequency and severity of musculoskeletal pain generally increases with age. To determine whether the density of sensory nerve fibers that transduce skeletal pain changes with age, calcitonin gene related peptide (CGRP) and neurofilament 200 kDa (NF200) sensory nerve fibers that innervate the femur were examined in the femurs of young (4 month old), middle-aged (13 month) and old (36 month) male F344/BNF1 rats. Whereas the bone quality showed a significant age-related decline, the density of CGRP+ and NF200+ nerve fibers that innervate the bone remained remarkably unchanged as well as the severity of acute skeletal fracture pain. Thus, while bone mass, quality and strength undergo a significant decline with age, the density of sensory nerve fibers that transduce noxious stimuli remain largely intact. These data may in part explain why musculoskeletal pain increases with age. PMID:20947214

Jimenez-Andrade, Juan M.; Mantyh, William G.; Bloom, Aaron P.; Freeman, Katie T.; Ghilardi, Joseph R.; Kuskowski, Michael A.; Mantyh, Patrick W.

2010-01-01

60

Endogenous NGF and Nerve Impulses Regulate the Collateral Sprouting of Sensory Axons in the Skin of the Adult Rat  

Microsoft Academic Search

We have investigated the co-involvement of enclogenous NGF and impulses in the collateral sprouting of cutaneous sensory nerves in adult rats, specifically the A&axons in- volved in mechanonociception and the C-fibers that mediate heat nociception. Their collateral sprouting was measured by the progressive expansion, respectively, of the behav- iorally defined \\

Jack Diamond; Michael Holmes; Michael Coughlin

1992-01-01

61

Nerve Growth Factors (NGF, BDNF) Enhance Axonal Regeneration but Are not Required for Survival of Adult Sensory Neurons  

Microsoft Academic Search

Largely on the basis of studies with nerve growth factor (NGF), it is now widely accepted that development of the peripheral nervous system of vertebrates is dependent in part on the interaction of immature sensory and autonomic neurons with specific survival factors that are derived from peripheral target fields. I have found, in marked contrast to an absolute requirement for

Ronald M. Lindsay

1988-01-01

62

TRESK channel contribution to nociceptive sensory neurons excitability: modulation by nerve injury  

PubMed Central

Background Neuronal hyperexcitability is a crucial phenomenon underlying spontaneous and evoked pain. In invertebrate nociceptors, the S-type leak K+ channel (analogous to TREK-1 in mammals) plays a critical role of in determining neuronal excitability following nerve injury. Few data are available on the role of leak K2P channels after peripheral axotomy in mammals. Results Here we describe that rat sciatic nerve axotomy induces hyperexcitability of L4-L5 DRG sensory neurons and decreases TRESK (K2P18.1) expression, a channel with a major contribution to total leak current in DRGs. While the expression of other channels from the same family did not significantly change, injury markers ATF3 and Cacna2d1 were highly upregulated. Similarly, acute sensory neuron dissociation (in vitro axotomy) produced marked hyperexcitability and similar total background currents compared with neurons injured in vivo. In addition, the sanshool derivative IBA, which blocked TRESK currents in transfected HEK293 cells and DRGs, increased intracellular calcium in 49% of DRG neurons in culture. Most IBA-responding neurons (71%) also responded to the TRPV1 agonist capsaicin, indicating that they were nociceptors. Additional evidence of a biological role of TRESK channels was provided by behavioral evidence of pain (flinching and licking), in vivo electrophysiological evidence of C-nociceptor activation following IBA injection in the rat hindpaw, and increased sensitivity to painful pressure after TRESK knockdown in vivo. Conclusions In summary, our results clearly support an important role of TRESK channels in determining neuronal excitability in specific DRG neurons subpopulations, and show that axonal injury down-regulates TRESK channels, therefore contributing to neuronal hyperexcitability. PMID:21527011

2011-01-01

63

Deceased expression of prostatic acid phosphatase in primary sensory neurons after peripheral nerve injury  

PubMed Central

Prostatic acid phosphatase (PAP) is expressed in nociceptive dorsal root ganglion (DRG) neurons and functions as an ectonucleotidase that dephosphorylates extracellular adenosine monophosphate (AMP) to adenosine to suppress pain via activating A1-adenosine receptor (A1R) in dorsal spinal cord. However, the effect of peripheral nerve injury on the expression of PAP has not been reported until now. In the present study we found that PAP expression in DRG neurons is significantly decreased from the 2nd day after peripheral nerve injury and reaches the bottom at the 14th. In addition, intrathecal PAP injection can reduce mechanical allodynia induced by spared nerve injury. Our findings suggest that the decrease of PAP is involved in pathophysiological mechanisms of neuropathic pain.

Huang, Bo; Li, Xia; Zhu, Xiao-Chun; Lu, Yi-Sheng

2014-01-01

64

[Post-operative functional evaluation of accessory nerve reconstruction].  

PubMed

A nerve reconstruction was performed in 20 patients whose spinal accessory nerve was resected during total neck dissection. Re-anastomosis or a cable graft was performed between both cut ends of the accessory nerve in 14 patients (accessory nerve reconstruction group), and between the peripheral cut end of the accessory nerve and the central cut end of the cervical nerve (C2 or C3) in 6 patients (cervical/accessory nerve reconstruction group). There was no difference in the postoperative shoulder functions between the reconstruction groups, and both groups were significantly better than the group without reconstruction (n = 13), although they tended to be poorer than the nerve preservation group (n = 41). PMID:24601096

Asakura, Koji; Honma, Tomo; Keira, Takashi; Nagaya, Tomonori; Himi, Tetsuo

2014-01-01

65

Limb lengthening and peripheral nerve function—factors associated with deterioration of conduction  

PubMed Central

Background and purpose Limb lengthening is performed for a diverse range of orthopedic problems. A high rate of complications has been reported in these patients, which include motor and sensory loss as a result of nerve damage. We investigated the effect of limb lengthening on peripheral nerve function. Patients and methods 36 patients underwent electrophysiological testing at 3 points: (1) preoperatively, (2) after application of external fixator/corticotomy but before lengthening, and (3) after lengthening. The limb-length discrepancy was due to a congenital etiology (n = 19), a growth disturbance (n = 9), or a traumatic etiology (n = 8). Results 2 of the traumatic etiology patients had significant changes evident on electrophysiological testing preoperatively. They both deteriorated further with lengthening. 7 of the 21 patients studied showed deterioration in nerve function after lengthening, but not postoperatively, indicating that this was due to the lengthening process and not to the surgical procedure. All of these patients had a congenital etiology for their leg-length discrepancy. Interpretation As detailed electrophysiological tests were carried out before surgery, after surgery but before lengthening, and finally after completion of lengthening, it was possible to distinguish between the effects of the operation and the effects of lengthening on nerve function. The results indicate that the etiology, site (femur or tibia), and nerve (common peroneal or tibial) had a bearing on the risk of nerve injury and that these factors had a far greater effect than the total amount of lengthening. PMID:24171677

2013-01-01

66

[Joint and sensory branch block of the obturator and femoral nerves in a case of femoral head osteonecrosis and arthritis].  

PubMed

The sensory innervation of the hip joint is complex. The joint and sensory branch block of the obturator and femoral nerves is effective for treating the pain caused due to different hip diseases. This could be an option to be considered in certain circumstances such as, being a surgical-anaesthetic high risk, or if there is significant overweight, It could also be useful on other occasions if the traumatoligist considers that it is better to delay hip replacement for a limited period. PMID:24656423

Cortiñas-Sáenz, M; Salmerón-Velez, G; Holgado-Macho, I A

2014-01-01

67

Triptolide improves nerve regeneration and functional recovery following crush injury to rat sciatic nerve.  

PubMed

Recently, accumulating data have demonstrated that triptolide exhibits neurotrophic and neuroprotective properties. However, the role of triptolide in repair and regeneration of peripheral nerve injury (PNI) has rarely been performed. The current study was designed to observe the possible beneficial effect of triptolide on promoting peripheral nerve regeneration in rats. Rats with sciatic nerve crush injury were administered daily with triptolide for 7 days. Axonal regeneration was evaluated by morphometric analysis and Fluoro-gold retrograde tracing. Motor functional recovery was evaluated by walking track analysis, electrophysiological assessment and histological appearance of target muscles. Levels of pro-inflammatory cytokines within injured nerves were also determined. The results demonstrated that triptolide was capable of promoting peripheral nerve regeneration. Additionally, triptolide significantly decreased the levels of pro-inflammatory cytokines within injured nerves. These findings indicate the possibility of developing triptolide as a therapeutic agent for PNI. The neuroprotective effects of triptolide might be associated with its anti-inflammatory properties. PMID:24406146

Zhang, Yong-Guang; Sheng, Qing-Song; Wang, Hong-Kun; Lv, Li; Zhang, Jun; Chen, Jian-Mei; Xu, Hao

2014-02-21

68

Intraoperative Facial Nerve Monitoring in the Surgery of Cerebellopontine Angle Tumors: Improved Preservation of Nerve Function  

Microsoft Academic Search

The surgery of cerebellopontine angle tumors has shown remarkable progress over the last 20 years due to improved microsurgical techniques. However, the dissection of the facial nerve may lead to postoperative paresis as the result of the surgical trauma and the disruption of blood supply over a large distance. The functional status of the nerve can be intraoperatively monitored by

Thomas Lenarz; Arne Ernst

1994-01-01

69

Histopathologic and functional effects of facial nerve following electrical stimulation  

Microsoft Academic Search

The aim of the study is to investigate the functional and histopathologic changes in facial nerve due to the application of\\u000a various violent and numerous electrical stimuli to the facial nerve. The study was carried out with Wistar rats weighing between\\u000a 200 and 300 g. The facial nerves of the subjects were located and stimulated with electrical stimulator. Then five groups

Emrah Sapmaz; Irfan Kaygusuz; Hayrettin Cengiz Alpay; Nusret Akpolat; Erol Keles; Turgut Karlidag; Israfil Orhan; Sinasi Yalcin

2010-01-01

70

Effect of Delayed Peripheral Nerve Repair on Nerve Regeneration, Schwann Cell Function and Target Muscle Recovery  

PubMed Central

Despite advances in surgical techniques for peripheral nerve repair, functional restitution remains incomplete. The timing of surgery is one factor influencing the extent of recovery but it is not yet clearly defined how long a delay may be tolerated before repair becomes futile. In this study, rats underwent sciatic nerve transection before immediate (0) or 1, 3, or 6 months delayed repair with a nerve graft. Regeneration of spinal motoneurons, 13 weeks after nerve repair, was assessed using retrograde labeling. Nerve tissue was also collected from the proximal and distal stumps and from the nerve graft, together with the medial gastrocnemius (MG) muscles. A dramatic decline in the number of regenerating motoneurons and myelinated axons in the distal nerve stump was observed in the 3- and 6-months delayed groups. After 3 months delay, the axonal number in the proximal stump increased 2–3 folds, accompanied by a smaller axonal area. RT-PCR of distal nerve segments revealed a decline in Schwann cells (SC) markers, most notably in the 3 and 6 month delayed repair samples. There was also a progressive increase in fibrosis and proteoglycan scar markers in the distal nerve with increased delayed repair time. The yield of SC isolated from the distal nerve segments progressively fell with increased delay in repair time but cultured SC from all groups proliferated at similar rates. MG muscle at 3- and 6-months delay repair showed a significant decline in weight (61% and 27% compared with contra-lateral side). Muscle fiber atrophy and changes to neuromuscular junctions were observed with increased delayed repair time suggestive of progressively impaired reinnervation. This study demonstrates that one of the main limiting factors for nerve regeneration after delayed repair is the distal stump. The critical time point after which the outcome of regeneration becomes too poor appears to be 3-months. PMID:23409189

Jonsson, Samuel; Wiberg, Rebecca; McGrath, Aleksandra M.; Novikov, Lev N.; Wiberg, Mikael; Novikova, Liudmila N.; Kingham, Paul J.

2013-01-01

71

Edaravone promotes functional recovery after mechanical peripheral nerve injury  

PubMed Central

Edaravone has been shown to reduce ischemia/reperfusion-induced peripheral nerve injury. However, the therapeutic effect of edaravone on peripheral nerve injury caused by mechanical factors is unknown. In the present study, we established a peripheral nerve injury model by crushing the sciatic nerve using hemostatic forceps, and then administered edaravone 3 mg/kg intraperitoneally. The sciatic functional index and superoxide dismutase activity of the sciatic nerve were increased, and the malondialdehyde level was decreased in animals in the edaravone group compared with those in the model group. Bcl-2 expression was increased, but Bax expression was decreased in anterior horn cells of the L4-6 spinal cord segments. These results indicated that edaravone has a neuroprotective effect following peripheral nerve injury caused by mechanical factors through alleviating free radical damage to cells and inhibiting lipid peroxidation, as well as regulating apoptosis-related protein expression. PMID:25374594

Zhang, Teng; Li, Zhengwei; Dong, Jianli; Nan, Feng; Li, Tao; Yu, Qing

2014-01-01

72

Edaravone promotes functional recovery after mechanical peripheral nerve injury.  

PubMed

Edaravone has been shown to reduce ischemia/reperfusion-induced peripheral nerve injury. However, the therapeutic effect of edaravone on peripheral nerve injury caused by mechanical factors is unknown. In the present study, we established a peripheral nerve injury model by crushing the sciatic nerve using hemostatic forceps, and then administered edaravone 3 mg/kg intraperitoneally. The sciatic functional index and superoxide dismutase activity of the sciatic nerve were increased, and the malondialdehyde level was decreased in animals in the edaravone group compared with those in the model group. Bcl-2 expression was increased, but Bax expression was decreased in anterior horn cells of the L4-6 spinal cord segments. These results indicated that edaravone has a neuroprotective effect following peripheral nerve injury caused by mechanical factors through alleviating free radical damage to cells and inhibiting lipid peroxidation, as well as regulating apoptosis-related protein expression. PMID:25374594

Zhang, Teng; Li, Zhengwei; Dong, Jianli; Nan, Feng; Li, Tao; Yu, Qing

2014-09-15

73

Effect of remote sensory noise on hand function post stroke.  

PubMed

Hand motor impairment persists after stroke. Sensory inputs may facilitate recovery of motor function. This pilot study tested the effectiveness of tactile sensory noise in improving hand motor function in chronic stroke survivors with tactile sensory deficits, using a repeated measures design. Sensory noise in the form of subthreshold, white noise, mechanical vibration was applied to the wrist skin during motor tasks. Hand dexterity assessed by the Nine Hole Peg Test and the Box and Block Test and pinch strength significantly improved when the sensory noise was turned on compared with when it was turned off in chronic stroke survivors. The subthreshold sensory noise to the wrist appears to induce improvements in hand motor function possibly via neuronal connections in the sensoriomotor cortex. The approach of applying concomitant, unperceivable mechanical vibration to the wrist during hand motor tasks is easily adoptable for clinic use as well as unsupervised home use. This pilot study suggests a potential for a wristband-type assistive device to complement hand rehabilitation for stroke survivors with sensorimotor deficit. PMID:25477806

Seo, Na Jin; Kosmopoulos, Marcella Lyn; Enders, Leah R; Hur, Pilwon

2014-01-01

74

Peripheral nerve lengthening as a regenerative strategy  

PubMed Central

Peripheral nerve injury impairs motor, sensory, and autonomic function, incurring substantial financial costs and diminished quality of life. For large nerve gaps, proximal lesions, or chronic nerve injury, the prognosis for recovery is particularly poor, even with autografts, the current gold standard for treating small to moderate nerve gaps. In vivo elongation of intact proximal stumps towards the injured distal stumps of severed peripheral nerves may offer a promising new strategy to treat nerve injury. This review describes several nerve lengthening strategies, including a novel internal fixator device that enables rapid and distal reconnection of proximal and distal nerve stumps. PMID:25317163

Vaz, Kenneth M.; Brown, Justin M.; Shah, Sameer B.

2014-01-01

75

Glycomimetic functionalized collagen hydrogels for peripheral nerve repair  

NASA Astrophysics Data System (ADS)

Despite the innate regenerative potential of the peripheral nervous system, functional recovery is often limited. The goal of this dissertation was to develop a clinically relevant biomaterial strategy to (1) encourage the regrowth of axons and (2) direct them down their appropriate motor tracts. To this end, we use peptide mimics of two glycans, polysialic acid (PSA) and an epitope first discovered on human natural killer cells (HNK-1), to functionalize type I collagen hydrogels. Previous studies have shown that these molecules, in their glycan and glycomimetic form, are associated with acceleration of neurite outgrowth, glial cell proliferation, and motoneuron targeting. In vitro, we demonstrated the retained functionality of the peptide glycomimetics after conjugation to a type I collagen backbone. While HNK-functionalized collagen increased motor neurite outgrowth, PSA-functionalized collagen encouraged motor and sensory neurite outgrowth and Schwann cell extension and proliferation. When we introduce these glycomimetic-functionalized collagen hydrogels into a critical gap femoral nerve model, we show that both PSA and HNK-functionalized hydrogels yielded a significant increase in functional recovery when compared to saline, native and scramble-coupled hydrogels. However, there was an interesting divergence in the morphological results: PSA-functionalized hydrogels increased axon count and HNK-functionalized hydrogels increased motoneuron targeting and myelination. We believed that these differences may be attributed to distinct mechanisms by which the glycomimetics impart their benefit. Interestingly, however, we found no synergistic gain in recovery with the use of our composite hydrogels which we speculated may be due to an inadequate dose of the individual glycomimetic. To address this possibility, we show that increasing the amount of functionalized peptide functionalized in our composite hydrogels led to increases in axon count and area of regeneration, but does not affect the degree of functional recovery. Finally, in order to assess potential mechanisms by which our glycomimetics impart benefit, we describe a novel platform for studying neural cell/biomaterial interaction through the use of two types of motoneuron cultures, dissociated spinal cord neurons and organotypic spinal cord slices. We show promising evidence that this strategy can be used to probe signaling pathways potentially involved in the action of these bioactives.

Masand, Shirley Narain

76

Mitochondrial DNA and gastrointestinal motor and sensory functions in health and functional gastrointestinal disorders.  

PubMed

Nerve, muscle, and inflammatory cells involved in gastrointestinal (GI) function have high-energy requirements and are affected in mitochondrial disorders. Familial aggregation of irritable bowel syndrome (IBS) frequently involves mothers and their children. Since mitochondrial DNA (mtDNA) is maternally inherited, mtDNA single nucleotide polymorphisms (SNPs) could confer risk to the development of IBS. The mtDNA SNPs, 16519C>T and 3010G>A, are associated with migraine and childhood cyclic vomiting syndrome. Our hypothesis is that these mtDNA SNPs are associated with functional GI disorders (FGIDs) and GI functions. The mt genome was first tested for the 7028C polymorphism (defining haplogroup H) in 699 patients or controls, and those with 7028C were further genotyped at 16519 and 3010. Phenotypes were based on symptoms (validated questionnaires and criteria) and GI physiology using validated motor and sensory studies. Constipation-predominant IBS and alternating constipation and diarrhea IBS are less prevalent in individuals with the 7028C mtDNA polymorphism than in individuals with 7028T. Conversely, 7028C is associated with higher maximum tolerated volume (lower satiation) compared with 7028T. Among those with 7028C, nonspecific abdominal pain (chronic abdominal pain or dyspepsia) was significantly associated with 3010A compared with 3010G (odds ratio 3.3, P=0.02), and slower gastric emptying was statistically associated with 3010G. There were no significant associations of mtDNA genotypes tested and stomach volumes, small bowel or colonic transit, rectal compliance, and motor or sensory functions. Thus variation in mtDNA may be associated with satiation, gastric emptying, and possibly pain; further studies of mtDNA in appetite regulation and larger numbers of patients with FGIDs are warranted. PMID:19147801

Camilleri, Michael; Carlson, Paula; Zinsmeister, Alan R; McKinzie, Sanna; Busciglio, Irene; Burton, Duane; Zaki, Essam A; Boles, Richard G

2009-03-01

77

The method of isolation of the crayfish abdominal stretch receptor maintaining a connection of the sensory neuron to the ventral nerve cord ganglion.  

PubMed

The crayfish stretch receptor consisting of the single mechanoreceptor neurons enveloped by satellite glial cells is the simplest functioning neuroglial preparation. However, during isolation, its axons are usually transected that eliminates afferent regulation and induces complex axotomy-related signaling responses in neurons and satellite glia. We developed new microsurgical method of crayfish stretch receptor isolation, which preserves connections of sensory neurons to the ventral nerve cord ganglion. The stretch receptor may either remain on the abdominal carapace, or be completely isolated. In both cases, it may be either intact, or axotomized. The integrity of axons was confirmed by firing recording from proximal and distal axon points. Normal, necrotic and apoptotic cells were visualized using double fluorochroming with Hoechst 33342 and propidium iodide. The isolated mechanoreceptor neurons maintain regular firing during 8-10 or more hours. Glial cells surrounding non-axotomized neurons demonstrate lower necrosis and apoptosis levels than the axotomized ones. Unlike the existing method, in which the sensory neurons were axotomized, the present method preserves links between the sensory neurons and the ganglion and makes possible to avoid consequences of axotomy in neurons and satellite glia. The present neuroglial preparation may be used as a simple but informative model object in studies of axotomy-induced degeneration and survival of peripheral neurons, the role of glia in neuron injury, the signaling mechanisms of neuroglial interactions, and the effects of diverse physical and chemical factors on neuronal and glial cells. PMID:25374161

Khaitin, Andrej M; Rudkovskii, Mikhail V; Uzdensky, Anatoly B

2015-03-01

78

Electrophysiological aspects of sensory conduction velocity in healthy adults. 1. Conduction velocity from digit to palm, from palm to wrist, and across the elbow, as a function of age.  

PubMed Central

The sensory conduction velocity from digit to palm and from palm to wrist was determined in median (digit 3) and ulnar (digit 5) nerves in 47 healthy subjects with age range from 21 to 77 years. The decrement of the sensory conduction as a function of age was more marked in the palm to wrist than in the digit to palm segment. Sensory conduction velocity of the ulnar nerve across the elbow was also studied. Irregularities in the shape of the sensory evoked potential recorded above the cubital sulcus were found in 12.76% of cases, especially in subjects over 50 years of age. These results suggest that aging causes decrement in sensory conduction and changes in the shape of the evoked potentials, especially at points where the nerves are more frequently compressed. Images PMID:731254

Cruz Martínez, A; Barrio, M; Pérez Conde, M C; Gutiérrez, A M

1978-01-01

79

Sciatic nerve injury in adult rats causes distinct changes in the central projections of sensory neurons expressing different glial cell line-derived neurotrophic factor family receptors.  

PubMed

Most small unmyelinated neurons in adult rat dorsal root ganglia (DRG) express one or more of the coreceptors targeted by glial cell line-derived neurotrophic factor (GDNF), neurturin, and artemin (GFRalpha1, GFRalpha2, and GFRalpha3, respectively). The function of these GDNF family ligands (GFLs) is not fully elucidated but recent evidence suggests GFLs could function in sensory neuron regeneration after nerve injury and peripheral nociceptor sensitization. In this study we used immunohistochemistry to determine if the DRG neurons targeted by each GFL change after sciatic nerve injury. We compared complete sciatic nerve transection and the chronic constriction model and found that the pattern of changes incurred by each injury was broadly similar. In lumbar spinal cord there was a widespread increase in neuronal GFRalpha1 immunoreactivity (IR) in the L1-6 dorsal horn. GFRalpha3-IR also increased but in a more restricted area. In contrast, GFRalpha2-IR decreased in patches of superficial dorsal horn and this loss was more extensive after transection injury. No change in calcitonin gene-related peptide-IR was detected after either injury. Analysis of double-immunolabeled L5 DRG sections suggested the main effect of injury on GFRalpha1- and GFRalpha3-IR was to increase expression in both myelinated and unmyelinated neurons. In contrast, no change in basal expression of GFRalpha2-IR was detected in DRG by analysis of fluorescence intensity and there was a small but significant reduction in GFRalpha2-IR neurons. Our results suggest that the DRG neuronal populations targeted by GDNF, neurturin, or artemin and the effect of exogenous GFLs could change significantly after a peripheral nerve injury. PMID:20533358

Keast, Janet R; Forrest, Shelley L; Osborne, Peregrine B

2010-08-01

80

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

PubMed

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. PMID:22147643

Henry, F P; Farkhad, R I; Butt, F S; O'Shaughnessy, M; O'Sullivan, S T

2012-06-01

81

Peripheral nerve function in patients with painful diabetic neuropathy treated with continuous subcutaneous insulin infusion.  

PubMed Central

In order to study the effects of improved metabolic control on painful diabetic polyneuropathy, 15 patients were treated with continuous subcutaneous insulin infusion over a 12 month period. Polyneuropathy was assessed by pain score, neurological examinations, nerve conduction studies and determination of sensory thresholds and cardiovascular reflexes. Improved metabolic control was confirmed by significantly improved levels of glycosylated haemoglobin (11.7 +/- 0.3% at entry to the study, to 8.7 +/- 0.3% after 12 months; mean +/- SEM). Symptomatic relief was confirmed by significantly improved pain scores. Thresholds for thermal cutaneous sensation improved significantly from 6.0 +/- 0.8 degrees C at entry to the study to 2.7 +/- 0.7 degrees C after 12 months (mean +/- SEM). These findings suggest a selective improvement of peripheral small nerve fibre function after continuous subcutaneous insulin infusion. The importance of quantitating thermal cutaneous sensation in longitudinal studies of patients with diabetic neuropathy was confirmed. PMID:3681313

Bertelsmann, F W; Heimans, J J; Van Rooy, J C; Dankmeijer, H F; Visser, S L; Van der Veen, E A

1987-01-01

82

Regeneration of putative sensory and sympathetic cutaneous nerve endings in the rat foot after sciatic nerve injury.  

PubMed

The present study examines the occurrence of calcitonin gene-related peptide-, substance P- and tyrosine hydroxylase-like immunoreactive profiles in glabrous and hairy foot skin from normal and nerve-injured rats. After neurotomy/suture, glabrous skin samples contain few calcitonin gene-related peptide-, substance P- and tyrosine hydroxylase-like immunoreactive profies. The number of calcitonin gene-related peptide- and substance P-like immunoreacive profiles in the epidermis is significantly subnormal. Hairy skin from these rats does also contain few calcitonin gene-related peptide-, substance P- and tyrosine hydroxylase-like immunoreactive profiles. In addition, the presence of epidermal calcitonin gene-related peptide-like imunoreactive profiles in glabrous skin is subnormal on the contralateral side. After nerve crush injury, the occurrence of calcitonin gene-related peptide-like, but not substance P-like, immunoreactive profiles in th epidermis of the glabrous skin is significantly subnormal. The occurrence of tyrosine hylase-like immnunoreactive fibres in relation to the digital artery is also subnormal. The occurrence in hairy skin of calcitonin gene-related peptide-like immunoreactive, substance P-like immunoreactive and tyrosine hydroxylase-like immunoreactive profiles is subnormal. In both skin types, the contralateral occurrence of such profiles is subjectively normal. These results show that the occurrence of calcitonin gene-related peptide-, substance P-, and tyrosine hydroxylase-like immunoreactive profiles in glabrous and hairy foot skin is clearly subnormal after neurotomy and suture and less abnormal after nerve crush. After neurotomy and suture the contralateral side is also affected. PMID:10970110

Stankovic, N; Johansson, O; Hildebrand, C

1996-01-01

83

Influence of Breaching the Connective Sheaths of the Donor Nerve on Its Myelinated Sensory Axons and on Their Sprouting into the End-to-Side Coapted Nerve in the Rat  

PubMed Central

Abstract The influence of breaching the connective sheaths of the donor sural nerve on axonal sprouting into the end-to-side coapted peroneal nerve was examined in the rat. In parallel, the effect of these procedures on the donor nerve was assessed. The sheaths of the donor nerve at the coaptation site were either left completely intact (group A) or they were breached by epineurial sutures (group B), an epineurial window (group C), or a perineurial window (group D). In group A, the compound action potential (CAP) of sensory axons was detected in ?10% and 40% of the recipient nerves at 4 and 8 weeks, respectively, which was significantly less frequently than in group D at both recovery periods. In addition, the number of myelinated axons in the recipient nerve was significantly larger in group D than in other groups at 4 weeks. At 8 weeks, the number of axons in group A was only ?15% of the axon numbers in other groups (p<0.05). Focal subepineurial degenerative changes in the donor nerves were only seen after 4 weeks, but not later. The average CAP area and the total number of myelinated axons in the donor nerves were not different among the experimental groups. In conclusion, myelinated sensory axons are able to penetrate the epiperineurium of donor nerves after end-to-side nerve coaption; however, their ingrowth into recipient nerves is significantly enhanced by breaching the epiperineurial sheets at the coaptation site. Breaching does not cause permanent injury to the donor nerve. PMID:22873667

Žele, Tilen; Tomši?, Martin; Sketelj, Janez; Bajrovi?, Fajko F.

2012-01-01

84

Microelectronic neural bridging of toad nerves to restore leg function?  

PubMed Central

The present study used a microelectronic neural bridge comprised of electrode arrays for neural signal detection, functional electrical stimulation, and a microelectronic circuit including signal amplifying, processing, and functional electrical stimulation to bridge two separate nerves, and to restore the lost function of one nerve. The left leg of one spinal toad was subjected to external mechanical stimulation and functional electrical stimulation driving. The function of the left leg of one spinal toad was regenerated to the corresponding leg of another spinal toad using a microelectronic neural bridge. Oscilloscope tracings showed that the electromyographic signals from controlled spinal toads were generated by neural signals that controlled the spinal toad, and there was a delay between signals. This study demonstrates that microelectronic neural bridging can be used to restore neural function between different injured nerves. PMID:25206698

Shen, Xiaoyan; Wang, Zhigong; Lv, Xiaoying; Huang, Zonghao

2013-01-01

85

Sciatic nerve injury induces apoptosis of dorsal root ganglion satellite glial cells and selectively modifies neurosteroidogenesis in sensory neurons.  

PubMed

Neurosteroids are synthesized either by glial cells, by neurons, or within the context of neuron-glia cross-talk. Various studies suggested neurosteroid involvement in the control of neurodegeneration but there is no evidence showing that the natural protection of nerve cells against apoptosis directly depends on their own capacity to produce neuroprotective neurosteroids. Here, we investigated the interactions between neurosteroidogenesis and apoptosis occurring in sensory structures of rats subjected to neuropathic pain generated by sciatic nerve chronic constriction injury (CCI). Using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), we observed no apoptotic cells in the spinal cord up to 30 days after CCI although pain symptoms such as mechano-allodynia, thermal and mechanical hyperalgesia were evidenced with the Hargreaves's behavioral and von Frey filament tests. In contrast, double-labeling experiments combining TUNEL and immunostaining with antibodies against glutamine synthetase or neuronal nuclei protein revealed apoptosis occurrence in satellite glial cells (SGC) (not in neurons) of CCI rat ipsilateral dorsal root ganglia (DRG) at day 30 after injury. Pulse-chase experiments coupled with high performance liquid chromatography and flow scintillation detection showed that, among numerous biosynthetic pathways converting [(3)H]pregnenolone into various [(3)H]neurosteroids, only [(3)H]estradiol formation was selectively modified and upregulated in DRG of CCI rats. Consistently, immunohistochemical investigations localized aromatase (estradiol-synthesizing enzyme) in DRG neurons but not in SGC. Pharmacological inhibition of aromatase caused apoptosis of CCI rat DRG neurons. Altogether, our results suggest that endogenously produced neurosteroids such as estradiol may be pivotal for the protection of DRG sensory neurons against sciatic nerve CCI-induced apoptosis. PMID:19565659

Schaeffer, Véronique; Meyer, Laurence; Patte-Mensah, Christine; Eckert, Anne; Mensah-Nyagan, Ayikoe G

2010-01-15

86

Histopathologic and functional effects of facial nerve following electrical stimulation.  

PubMed

The aim of the study is to investigate the functional and histopathologic changes in facial nerve due to the application of various violent and numerous electrical stimuli to the facial nerve. The study was carried out with Wistar rats weighing between 200 and 300 g. The facial nerves of the subjects were located and stimulated with electrical stimulator. Then five groups were created with 18 subjects in each group: Group 1, 1 milliampere (mA) electrical stimulus applied; Group 2, 2 mA electrical stimulus applied; Group 3, 3 mA electrical stimulus applied; Group 4, 4 mA electrical stimulus applied; Group 5, 5 mA electrical stimulus applied. All groups were divided into three sub-groups, each consisting of six subjects. The facial nerves of the subjects in first sub-group were stimulated 10 times, in second sub-group were stimulated 20 times and those in third sub-group were stimulated 30 times. The functions of the facial nerves were evaluated on first day, first week and first month, respectively. The facial nerves with branches were dissected from the surrounding tissues carefully. These specimens were investigated by light microscope about axonal degeneration, macrovacuolization and vascular congestion. Loss of facial functions was not observed in the subjects during follow-up process. There was no significant difference between groups regarding axonal degeneration, macrovacuolization and vascular congestion (P > 0.05). While less axonal degeneration was observed in group which was stimulated 10 times, more axonal degeneration was observed in groups which were stimulated 20 and 30 times (P < 0.05). The axonal degeneration, macrovacuolization and vascular congestion were observed more in 1-day groups (P < 0.05). Consequently, lesser violence and lesser number of electrical stimulus application to the facial nerve appears to be an important criterion for not damaging the facial nerve in patients in whom stimulators have been used. PMID:19784664

Sapmaz, Emrah; Kaygusuz, Irfan; Alpay, Hayrettin Cengiz; Akpolat, Nusret; Keles, Erol; Karlidag, Turgut; Orhan, Israfil; Yalcin, Sinasi

2010-04-01

87

Mesenchymal stem cells and their secretome partially restore nerve and urethral function in a dual muscle and nerve injury stress urinary incontinence model.  

PubMed

Childbirth injures muscles and nerves responsible for urinary continence. Mesenchymal stem cells (MSCs) or their secretome given systemically could provide therapeutic benefit for this complex multisite injury. We investigated whether MSCs or their secretome, as collected from cell culture, facilitate recovery from simulated childbirth injury. Age-matched female Sprague-Dawley rats received pudendal nerve crush and vaginal distension (PNC+VD) and a single intravenous (iv) injection of 2 million MSCs or saline. Controls received sham injury and iv saline. Additional rats received PNC+VD and a single intraperitoneal (ip) injection of concentrated media conditioned by MSCs (CCM) or concentrated control media (CM). Controls received a sham injury and ip CM. Urethral and nerve function were assessed with leak point pressure (LPP) and pudendal nerve sensory branch potential (PNSBP) recordings 3 wk after injury. Urethral and pudendal nerve anatomy were assessed qualitatively by blinded investigators. Quantitative data were analyzed using one-way ANOVA and Holm-Sidak post hoc tests with P < 0.05 indicating significant differences. Both LPP and PNSBP were significantly decreased 3 wk after PNC+VD with saline or CM compared with sham-injured rats, but not with MSC or CCM. Elastic fiber density in the urethra increased and changed in orientation after PNC+VD, with a greater increase in elastic fibers with MSC or CCM. Pudendal nerve fascicles were less dense and irregularly shaped after PNC+VD and had reduced pathology with MSC or CCM. MSC and CCM provide similar protective effects after PNC+VD, suggesting that MSCs act via their secretions in this dual muscle and nerve injury. PMID:25377914

Deng, Kangli; Lin, Dan Li; Hanzlicek, Brett; Balog, Brian; Penn, Marc S; Kiedrowski, Matthew J; Hu, Zhiquan; Ye, Zhangqun; Zhu, Hui; Damaser, Margot S

2015-01-15

88

TRESK channel contribution to nociceptive sensory neurons excitability: modulation by nerve injury  

Microsoft Academic Search

Background  Neuronal hyperexcitability is a crucial phenomenon underlying spontaneous and evoked pain. In invertebrate nociceptors, the\\u000a S-type leak K+ channel (analogous to TREK-1 in mammals) plays a critical role of in determining neuronal excitability following nerve injury.\\u000a Few data are available on the role of leak K2P channels after peripheral axotomy in mammals.\\u000a \\u000a \\u000a \\u000a \\u000a Results  Here we describe that rat sciatic nerve axotomy

Astrid Tulleuda; Barbara Cokic; Gerard Callejo; Barbara Saiani; Jordi Serra; Xavier Gasull

2011-01-01

89

Tiotropium modulates transient receptor potential V1 (TRPV1) in airway sensory nerves: A beneficial off-target effect???  

PubMed Central

Background Recent studies have suggested that the long-acting muscarinic receptor antagonist tiotropium, a drug widely prescribed for its bronchodilator activity in patients with chronic obstructive pulmonary disease and asthma, improves symptoms and attenuates cough in preclinical and clinical tussive agent challenge studies. The mechanism by which tiotropium modifies tussive responses is not clear, but an inhibition of vagal tone and a consequent reduction in mucus production from submucosal glands and bronchodilation have been proposed. Objective The aim of this study was to investigate whether tiotropium can directly modulate airway sensory nerve activity and thereby the cough reflex. Methods We used a conscious cough model in guinea pigs, isolated vagal sensory nerve and isolated airway neuron tissue– and cell-based assays, and in vivo single-fiber recording electrophysiologic techniques. Results Inhaled tiotropium blocked cough and single C-fiber firing in the guinea pig to the transient receptor potential (TRP) V1 agonist capsaicin, a clinically relevant tussive stimulant. Tiotropium and ipratropium, a structurally similar muscarinic antagonist, inhibited capsaicin responses in isolated guinea pig vagal tissue, but glycopyrrolate and atropine did not. Tiotropium failed to modulate other TRP channel–mediated responses. Complementary data were generated in airway-specific primary ganglion neurons, demonstrating that tiotropium inhibited capsaicin-induced, but not TRPA1-induced, calcium movement and voltage changes. Conclusion For the first time, we have shown that tiotropium inhibits neuronal TRPV1-mediated effects through a mechanism unrelated to its anticholinergic activity. We speculate that some of the clinical benefit associated with taking tiotropium (eg, in symptom control) could be explained through this proposed mechanism of action. PMID:24506933

Birrell, Mark A.; Bonvini, Sara J.; Dubuis, Eric; Maher, Sarah A.; Wortley, Michael A.; Grace, Megan S.; Raemdonck, Kristof; Adcock, John J.; Belvisi, Maria G.

2014-01-01

90

Sensory Neuron Signaling to the Brain: Properties of Transmitter Release from Olfactory Nerve Terminals  

Microsoft Academic Search

olfactory bulb glomeruli. To better understand the process by which information contained in the odorant-evoked firing of ORNs is transmitted to the brain, we examined the properties of glutamate release from olfactory nerve (ON) terminals in slices of the rat olfactory bulb. We show that marked paired pulse depression is the same in simultaneously recorded periglomerular and tufted neurons, and

Gabe J. Murphy; Lindsey L. Glickfeld; Zev Balsen; Jeffry S. Isaacson

2004-01-01

91

Challenges for stem cells to functionally repair the damaged auditory nerve  

PubMed Central

Introduction In the auditory system, a specialised subset of sensory neurons are responsible for correctly relaying precise pitch and temporal cues to the brain. In individuals with severe-to-profound sensorineural hearing impairment these sensory auditory neurons can be directly stimulated by a cochlear implant, which restores sound input to the brainstem after the loss of hair cells. This neural prosthesis therefore depends on a residual population of functional neurons in order to function effectively. Areas covered In severe cases of sensorineural hearing loss where the numbers of auditory neurons are significantly depleted, the benefits derived from a cochlear implant may be minimal. One way in which to restore function to the auditory nerve is to replace these lost neurons using differentiated stem cells, thus re-establishing the neural circuit required for cochlear implant function. Such a therapy relies on producing an appropriate population of electrophysiologically functional neurons from stem cells, and on these cells integrating and reconnecting in an appropriate manner in the deaf cochlea. Expert opinion Here we review progress in the field to date, including some of the key functional features that stem cell-derived neurons would need to possess and how these might be enhanced using electrical stimulation from a cochlear implant. PMID:23094991

Needham, K; Minter, R.L.; Shepherd, R.K.; Nayagam, B.A.

2012-01-01

92

The Association between Sensory Impairment and Functional Limitations in Balance in Community-Dwelling Older Adults  

E-print Network

for falls. The Fullerton Advanced Balance (FAB) Scale is a functional limitation test that measures multipleThe Association between Sensory Impairment and Functional Limitations in Balance in Community contribute to the ability to control balance (e.g.,peripheral sensory, central sensory processing

de Lijser, Peter

93

A biomaterials approach to peripheral nerve regeneration: bridging the peripheral nerve gap and enhancing functional recovery  

PubMed Central

Microsurgical techniques for the treatment of large peripheral nerve injuries (such as the gold standard autograft) and its main clinically approved alternative—hollow nerve guidance conduits (NGCs)—have a number of limitations that need to be addressed. NGCs, in particular, are limited to treating a relatively short nerve gap (4 cm in length) and are often associated with poor functional recovery. Recent advances in biomaterials and tissue engineering approaches are seeking to overcome the limitations associated with these treatment methods. This review critically discusses the advances in biomaterial-based NGCs, their limitations and where future improvements may be required. Recent developments include the incorporation of topographical guidance features and/or intraluminal structures, which attempt to guide Schwann cell (SC) migration and axonal regrowth towards their distal targets. The use of such strategies requires consideration of the size and distribution of these topographical features, as well as a suitable surface for cell–material interactions. Likewise, cellular and molecular-based therapies are being considered for the creation of a more conductive nerve microenvironment. For example, hurdles associated with the short half-lives and low stability of molecular therapies are being surmounted through the use of controlled delivery systems. Similarly, cells (SCs, stem cells and genetically modified cells) are being delivered with biomaterial matrices in attempts to control their dispersion and to facilitate their incorporation within the host regeneration process. Despite recent advances in peripheral nerve repair, there are a number of key factors that need to be considered in order for these new technologies to reach the clinic. PMID:22090283

Daly, W.; Yao, L.; Zeugolis, D.; Windebank, A.; Pandit, A.

2012-01-01

94

A biomaterials approach to peripheral nerve regeneration: bridging the peripheral nerve gap and enhancing functional recovery.  

PubMed

Microsurgical techniques for the treatment of large peripheral nerve injuries (such as the gold standard autograft) and its main clinically approved alternative--hollow nerve guidance conduits (NGCs)--have a number of limitations that need to be addressed. NGCs, in particular, are limited to treating a relatively short nerve gap (4 cm in length) and are often associated with poor functional recovery. Recent advances in biomaterials and tissue engineering approaches are seeking to overcome the limitations associated with these treatment methods. This review critically discusses the advances in biomaterial-based NGCs, their limitations and where future improvements may be required. Recent developments include the incorporation of topographical guidance features and/or intraluminal structures, which attempt to guide Schwann cell (SC) migration and axonal regrowth towards their distal targets. The use of such strategies requires consideration of the size and distribution of these topographical features, as well as a suitable surface for cell-material interactions. Likewise, cellular and molecular-based therapies are being considered for the creation of a more conductive nerve microenvironment. For example, hurdles associated with the short half-lives and low stability of molecular therapies are being surmounted through the use of controlled delivery systems. Similarly, cells (SCs, stem cells and genetically modified cells) are being delivered with biomaterial matrices in attempts to control their dispersion and to facilitate their incorporation within the host regeneration process. Despite recent advances in peripheral nerve repair, there are a number of key factors that need to be considered in order for these new technologies to reach the clinic. PMID:22090283

Daly, W; Yao, L; Zeugolis, D; Windebank, A; Pandit, A

2012-02-01

95

The impact and specificity of nerve perturbation on novel vibrotactile sensory letter learning.  

PubMed

The purposes of this study were to determine if induced radiating paresthesia interferes with (a) acquisition and/or (b) utilization of complex tactile information, and (c) identify whether interference reflects tactile masking or response competition. Radiating ulnar (experiment 1) and median (experiment 2) nerve paresthesia was quantified on ulnar innervated vibrotactile Morse code letter acquisition and recollection tasks. Induced paresthesia differentially impacted letter acquisition and recollection, but only when presented to the same anatomical spatial location. PMID:24844345

Passmore, Steven R; Bosse, Jessica; Murphy, Bernadette; Lee, Timothy D

2014-12-01

96

Substitution of natural sensory input by artificial neurostimulation of an amputated trigeminal nerve does not prevent the degeneration of basal forebrain cholinergic circuits projecting to the somatosensory cortex  

PubMed Central

Peripheral deafferentation downregulates acetylcholine (ACh) synthesis in sensory cortices. However, the responsible neural circuits and processes are not known. We irreversibly transected the rat infraorbital nerve and implanted neuroprosthetic microdevices for proximal stump stimulation, and assessed cytochrome-oxidase and choline- acetyl-transferase (ChAT) in somatosensory, auditory and visual cortices; estimated the number and density of ACh-neurons in the magnocellular basal nucleus (MBN); and localized down-regulated ACh-neurons in basal forebrain using retrograde labeling from deafferented cortices. Here we show that nerve transection, causes down regulation of MBN cholinergic neurons. Stimulation of the cut nerve reverses the metabolic decline but does not affect the decrease in cholinergic fibers in cortex or cholinergic neurons in basal forebrain. Artifical stimulation of the nerve also has no affect of ACh-innervation of other cortices. Cortical ChAT depletion is due to loss of corticopetal MBN ChAT-expressing neurons. MBN ChAT downregulation is not due to a decrease of afferent activity or to a failure of trophic support. Basalocortical ACh circuits are sensory specific, ACh is provided to each sensory cortex “on demand” by dedicated circuits. Our data support the existence of a modality-specific cortex-MBN-cortex circuit for cognitive information processing. PMID:25452715

Herrera-Rincon, Celia; Panetsos, Fivos

2014-01-01

97

Sensory Responsiveness as a Predictor of Social Severity in Children with High Functioning Autism Spectrum Disorders  

ERIC Educational Resources Information Center

This study examines the relationship between sensory responsiveness and social severity in children with high functioning autism spectrum disorders (HFASD; N = 36) and age-matched controls (N = 26) between 6 and 10 years old. Significant relationships were found between social responsiveness scale scores and each of the six sensory profile sensory

Hilton, Claudia L.; Harper, Jacquelyn D.; Kueker, Rachel Holmes; Lang, Andrea Runzi; Abbacchi, Anna M.; Todorov, Alexandre; LaVesser, Patricia D.

2010-01-01

98

Evolution of peripheral nerve function in humans: novel insights from motor nerve excitability  

PubMed Central

While substantial alterations in myelination and axonal growth have been described during maturation, their interactions with the configuration and activity of axonal membrane ion channels to achieve impulse conduction have not been fully elucidated. The present study utilized axonal excitability techniques to compare the changes in nerve function across healthy infants, children, adolescents and adults. Multiple excitability indices (stimulus–response curve, strength–duration time constant, threshold electrotonus, current–threshold relationship and recovery cycle) combined with conventional neurophysiological measures were investigated in 57 subjects (22 males, 35 females; age range 0.46–24 years), stimulating the median motor nerve at the wrist. Maturational changes in conduction velocity were paralleled by significant alterations in multiple excitability parameters, similarly reaching steady values in adolescence. Maturation was accompanied by reductions in threshold (P < 0.005) and rheobase (P= 0.001); depolarizing and hyperpolarizing electrotonus progressively reduced (P < 0.001), or ‘fanned-in’; resting current–threshold slope increased (P < 0.0001); accommodation to depolarizing currents prolonged (P < 0.0001); while greater threshold changes in refractoriness (P= 0.001) and subexcitability (P < 0.01) emerged. Taken together, the present findings suggest that passive membrane conductances and the activity of K+ conductances decrease with formation of the axo-glial junction and myelination. In turn, these functional alterations serve to enhance the efficiency and speed of impulse conduction concurrent with the acquisition of motor skills during childhood, and provide unique insight into the evolution of postnatal human peripheral nerve function. Significantly, these findings bring the dynamics of axonal development to the clinical domain and serve to further illuminate pathophysiological mechanisms that occur during development. PMID:23006483

Farrar, Michelle A; Park, Susanna B; Lin, Cindy S-Y; Kiernan, Matthew C

2013-01-01

99

Relationship of estimated dietary intake of n-3 polyunsaturated fatty acids from fish with peripheral nerve function after adjusting for mercury exposure  

PubMed Central

Background Some clinical studies have suggested that ingestion of n-3 polyunsaturated fatty acids (PUFA) has neuroprotective effects on peripheral nerve function. However, few epidemiological studies have examined the effect of dietary n-3 PUFA intake from fish consumption on peripheral nerve function, and none have controlled for co-occurrence of methylmercury exposure from fish consumption. Objectives We evaluated the effect of estimated dietary n-3 PUFA intake on peripheral nerve function after adjusting for biomarkers of methylmercury and elemental mercury in a convenience sample of 515 dental professionals. Methods We measured sensory nerve conduction (peak latency and amplitude) of the median, ulnar and sural nerves and total mercury concentrations in hair and urine samples. We estimated daily intake (mg/day) of the total n-3 PUFA, n-3 docosahexaenoic acid (DHA), and n-3 eicosapentaenoic acid (EPA) based on a self-administrated fish consumption frequency questionnaire. We also collected information on mercury exposure, demographics and other covariates. Results The estimated median intakes of total n-3 PUFA, n-3 EPA, and n-3 DHA were 447, 105, and 179 mg/day, respectively. The mean mercury concentrations in urine (1.05?g/L) and hair (0.49?g/g) were not significantly different from the US general population. We found no consistent association between n-3 PUFA intake and sensory nerve conduction after adjusting for mercury concentrations in hair and urine although some positive associations were observed with the sural nerve. Conclusions In a convenience sample of dental professionals, we found little evidence suggesting that dietary intake of n-3 PUFAs from fish has any impact on peripheral nerve function after adjustment for methylmercury exposure from fish and elemental mercury exposure from dental amalgam. PMID:23538138

Wang, Yi; Goodrich, Jaclyn M.; Werner, Robert; Gillespie, Brenda; Basu, Niladri; Franzblau, Alfred

2013-01-01

100

Different effects of blocked potassium channels on action potentials, accommodation, adaptation and anode break excitation in human motor and sensory myelinated nerve fibres: computer simulations  

Microsoft Academic Search

.  ?Action potentials and electrotonic responses to 300-ms depolarizing and hyperpolarizing currents for human motor and sensory\\u000a myelinated nerve fibres have been simulated on the basis of double cable models. The effects of blocked nodal or internodal\\u000a potassium (fast or slow) channels on the fibre action potentials, early and late adaptations to 30-ms suprathreshold slowly\\u000a increasing depolarizing stimuli have been examined.

D. I. Stephanova; K. Mileva

2000-01-01

101

Functional Recovery After Facial and Sciatic Nerve Crush Injury in the Rat  

Microsoft Academic Search

Objectives: To systematically record rat facial nerve re- covery following crush injury to the main trunk with re- spect to ocular and vibrissial function and to compare the rates of facial and sciatic nerve recovery from crush injury in the same animals. This serves as a means of vali- dating the functional parameters of facial nerve recov- ery against the

Tessa A. Hadlock; James Heaton; Mack Cheney; Susan E. Mackinnon

2005-01-01

102

Evidence for a role of capsaicin-sensitive sensory nerves in the lung oedema induced by Tityus serrulatus venom in rats.  

PubMed

In the most severe cases of human envenoming by Tityus serrulatus, pulmonary oedema is a frequent finding and can be the cause of death. We have previously demonstrated a role for neuropeptides acting on tachykinin NK(1) receptors in the development of lung oedema following i.v. injection of T. serrulatus venom (TsV) in experimental animals. The present work was designed to investigate whether capsaicin-sensitive primary afferent neurons were a potential source of NK(1)-acting neuropeptides. To this end, sensory nerves were depleted of neuropeptides by neonatal treatment of rats with capsaicin. The effectiveness of this strategy at depleting sensory nerves was demonstrated by the inhibition of the neuropeptide-dependent response to intraplantar injection of formalin. Pulmonary oedema, as assessed by the levels of extravasation of Evans blue dye in the bronchoalveolar lavage and in the left lung, was markedly inhibited in capsaicin-treated animals. In contrast, capsaicin treatment failed to alter the increase in arterial blood pressure or the lethality following i.v. injection of TsV. Our results demonstrate an important role for capsaicin-sensitive sensory nerves in the cascade of events leading to lung injury following the i.v. administration of TsV. PMID:11711125

Andrade, Marcus V M; Souza, Danielle G; de A Castro, Maria Salete; Cunha-Melo, José R; Teixeira, Mauro M

2002-03-01

103

Long term functional plasticity of sensory inputs mediated by olfactory learning  

PubMed Central

Sensory inputs are remarkably organized along all sensory pathways. While sensory representations are known to undergo plasticity at the higher levels of sensory pathways following peripheral lesions or sensory experience, less is known about the functional plasticity of peripheral inputs induced by learning. We addressed this question in the adult mouse olfactory system by combining odor discrimination studies with functional imaging of sensory input activity in awake mice. Here we show that associative learning, but not passive odor exposure, potentiates the strength of sensory inputs up to several weeks after the end of training. We conclude that experience-dependent plasticity can occur in the periphery of adult mouse olfactory system, which should improve odor detection and contribute towards accurate and fast odor discriminations. DOI: http://dx.doi.org/10.7554/eLife.02109.001 PMID:24642413

Abraham, Nixon M; Vincis, Roberto; Lagier, Samuel; Rodriguez, Ivan; Carleton, Alan

2014-01-01

104

Acceleration of ulcer healing by cholecystokinin (CCK): role of CCK-A receptors, somatostatin, nitric oxide and sensory nerves.  

PubMed

CCK exhibits a potent cytoprotective activity against acute gastric lesions, but its role in ulcer healing has been little examined. In this study we determined whether exogenous CCK or endogenously released CCK by camostate, an inhibitor of luminal proteases, or by the diversion of pancreatico-biliary secretion from the duodenum, could affect ulcer healing. In addition, the effects of antagonism of CCK-A receptors (by loxiglumide, LOX) or CCK-B receptors (by L-365,260), an inhibition of NO-synthase by N(G)-nitro-L-arginine (L-NNA), or sensory denervation by large neurotoxic dose of capsaicin on CCK-induced ulcer healing were examined. Gastric ulcers were produced by serosal application of acetic acid and animals were sacrificed 9 days after ulcer induction. The area of ulcers and blood flow at the ulcer area were determined. Plasma levels of gastrin and CCK and luminal somatostatin were measured by RIA and mucosal biopsy samples were taken for histological evaluation and measurement of DNA synthesis. CCK given s.c. reduced dose dependently the ulcer area; the threshold dose of CCK being 1 nmol/kg and the dose inhibiting this area by 50% being 5 nmol/kg. This healing effect of CCK was accompanied by a significant increase in the GBF at ulcer margin and the rise in luminal NO production, plasma gastrin level and DNA synthesis. Concurrent treatment with LOX, completely abolished the CCK-8-induced acceleration of the ulcer healing and the rise in the GBF at the ulcer margin, whereas L-365,260 remained without any influence. Treatment with camostate or diversion of pancreatic juice that raised plasma CCK level to that observed with administration of CCK-8, also accelerated ulcer healing and this effect was also attenuated by LOX but not by L-365,260. Inhibition of NO-synthase by L-NNA significantly delayed ulcer healing and reversed the CCK-8 induced acceleration of ulcer healing, hyperemia at the ulcer margin and luminal NO release, and these effects were restored by the addition to L-NNA of L-arginine but not D-arginine. Capsaicin denervation attenuated CCK-induced ulcer healing, and the accompanying rise in the GBF at the ulcer margin and decreased plasma gastrin and luminal release of somatostatin when compared to those in rats with intact sensory nerves. Detectable signals for CCK-A and B receptor mRNAs as well as for cNOS mRNA expression were recorded by RT-PCR in the vehicle control gastric mucosa. The expression of CCK-A receptor mRNA and cNOS mRNA was significantly increased in rats treated with CCK-8 and camostate, whereas CCK-B receptor mRNA remained unaffected. We conclude that CCK accelerates ulcer healing by the mechanism involving upregulation of specific CCK-A receptors, enhancement of somatostatin release, stimulation of sensory nerves and hyperemia in the ulcer area, possibly mediated by NO. PMID:10458643

Brzozowski, T; Konturek, P C; Konturek, S J; Pajdo, R; Drozdowicz, D; Kwiecie?, S; Hahn, E G

1999-06-30

105

[Microtubules in the nerve cells: morphological and functional aspects].  

PubMed

The modern literature concerning ultrastructure and cytochemistry of microtubules in the nervous tissue is reviewed. Common features of cytological and biochemical organization of microtubules in different parts of the nervous system of the vertebrates and invertebrates are analysed: the similarity of ultrastructure of microtubules and their molecular organization (tubulin and its alpha- and beta-monomeres), the ability of microtubules to assemble and disassemble, to bind specifically with poisons--colchicine and vinblastine, participation of microtubules in the neuroplastic transport. The authors' data on space arrangement of microtubules within cytoplasm of the neuronal processes (dendrites and unmyelinated axons in the central and peripheral nevous system) are presented. Some literature and personal results concerning ultrastructure of neurofilaments and microtubules in the myelinated nerve fibres are also considered. The functional significance of microtubules in the nervous system is discussed with special reference to facts and hypotheses on a possible role of microtubules in the propagation of nerve impulse. PMID:7447728

Vorob'ev, V S; Portuganov, V V

1980-10-01

106

Can amino-functionalized carbon nanotubes carry functional nerve growth factor?  

PubMed Central

Carbon nanotubes can carry protein into cells to induce biological effects. Amino-functionalized carbon nanotubes are soluble and biocompatible, have high reactivity and low toxicity, and can help promote nerve cell growth. In this study, amino-functionalized ethylenediamine-treated multi-walled carbon nanotubes were used to prepare carbon nanotubes-nerve growth factor complexes by non-covalent grafting. The physicochemical properties, cytotoxicity to PC12 and chick embryo dorsal root ganglion, and biological activity of the carbon nanotubes-nerve growth factor complexes were investigated. The results showed that amino functionalization improved carbon nanotubes-nerve growth factor complex dispersibility, reduced their toxicity to PC12 cells, and promoted PC12 cell differentiation and chick embryo dorsal root ganglion. PMID:25206814

Chen, Wen; Xiong, Qing; Ren, Quanxia; Guo, Yake; Li, Gao

2014-01-01

107

Low-Level Laser Irradiation Improves Functional Recovery and Nerve Regeneration in Sciatic Nerve Crush Rat Injury Model  

PubMed Central

The development of noninvasive approaches to facilitate the regeneration of post-traumatic nerve injury is important for clinical rehabilitation. In this study, we investigated the effective dose of noninvasive 808-nm low-level laser therapy (LLLT) on sciatic nerve crush rat injury model. Thirty-six male Sprague Dawley rats were divided into 6 experimental groups: a normal group with or without 808-nm LLLT at 8 J/cm2 and a sciatic nerve crush injury group with or without 808-nm LLLT at 3, 8 or 15 J/cm2. Rats were given consecutive transcutaneous LLLT at the crush site and sacrificed 20 days after the crush injury. Functional assessments of nerve regeneration were analyzed using the sciatic functional index (SFI) and hindlimb range of motion (ROM). Nerve regeneration was investigated by measuring the myelin sheath thickness of the sciatic nerve using transmission electron microscopy (TEM) and by analyzing the expression of growth-associated protein 43 (GAP43) in sciatic nerve using western blot and immunofluorescence staining. We found that sciatic-injured rats that were irradiated with LLLT at both 3 and 8 J/cm2 had significantly improved SFI but that a significant improvement of ROM was only found in rats with LLLT at 8 J/cm2. Furthermore, the myelin sheath thickness and GAP43 expression levels were significantly enhanced in sciatic nerve-crushed rats receiving 808-nm LLLT at 3 and 8 J/cm2. Taken together, these results suggest that 808-nm LLLT at a low energy density (3 J/cm2 and 8 J/cm2) is capable of enhancing sciatic nerve regeneration following a crush injury. PMID:25119457

Wang, Chau-Zen; Chen, Yi-Jen; Wang, Yan-Hsiung; Yeh, Ming-Long; Huang, Mao-Hsiung; Ho, Mei-Ling; Liang, Jen-I; Chen, Chia-Hsin

2014-01-01

108

Partial Recovery of Respiratory Function and Diaphragm Reinnervation following Unilateral Vagus Nerve to Phrenic Nerve Anastomosis in Rabbits  

PubMed Central

Respiratory dysfunction is the leading cause of mortality following upper cervical spinal cord injury (SCI). Reinnervation of the paralyzed diaphragm via an anastomosis between phrenic nerve and a donor nerve is a potential strategy to mitigate ventilatory deficits. In this study, anastomosis of vagus nerve (VN) to phrenic nerve (PN) in rabbits was performed to assess the potential capacity of the VN to compensate for lost PN inputs. At first, we compared spontaneous discharge pattern, nerve thickness and number of motor fibers between these nerves. The PN exhibited a highly rhythmic discharge while the VN exhibited a variable frequency discharge pattern. The rabbit VN had fewer motor axons (105.3±12.1 vs. 268.1±15.4). Nerve conduction and respiratory function were measured 20 weeks after left PN transection with or without left VN-PN anastomosis. Compared to rabbits subjected to unilateral phrenicotomy without VN-PN anastomosis, diaphragm muscle action potential (AP) amplitude was improved by 292%, distal latency by 695%, peak inspiratory flow (PIF) by 22.6%, peak expiratory flow (PRF) by 36.4%, and tidal volume by 21.8% in the anastomosis group. However, PIF recovery was only 28.0%, PEF 28.2%, and tidal volume 31.2% of Control. Our results suggested that VN-PN anastomosis is a promising therapeutic strategy for partial restoration of diaphragm reinnervation, but further modification and improvements are necessary to realize the full potential of this technique. PMID:24265777

Li, Lijun; Sun, Guixin; Tan, Jun

2013-01-01

109

The sensory innervation of the pineal organ in the lizard, Lacerta viridis , with remarks on its position in the trend of pineal phylogenetic structural and functional evolution  

Microsoft Academic Search

The sensory innervation of the pineal organ of adult Lacerta viridis has been investigated. Some specimens of Lacerta muralis lillfordi were also used. In the pineal epithelium, a small number of nerve cell pericarya of a sensory type are present. They lie either solitary or in small clusters close to the basement membrane. The axons originating from the nerve cell

J. Ariëns Kappers

1967-01-01

110

New Chemically Functionalized Nanomaterials for Electrical Nerve Agents Sensors  

NASA Astrophysics Data System (ADS)

A chemical receptor specific to traces of organophosphorus nerve agents (OPs) has been synthesized and grafted to carbon nanotubes and silicon nanowires in order to make electrical sensors. Our results show that it is possible to detect efficiently sub-ppm traces of OPs with excellent selectivity notably with the use of silicon nanowires by monitoring the Drain-Source current of the SiNW-FET at an optimum back Gate voltage as a function of time. First developments of a prototype have also been realized.

Simonato, Jean-Pierre; Clavaguera, Simon; Carella, Alexandre; Delalande, Michael; Raoul, Nicolas; Lenfant, Stephane; Vuillaume, Dominique; Dubois, Emmanuel

2011-08-01

111

Rate-intensity functions in the emu auditory nerve.  

PubMed

Rate-versus-intensity functions recorded from mammalian auditory-nerve fibers have been shown to form a continuum of shapes, ranging from saturating to straight and correlating well with spontaneous rate and sensitivity. These variations are believed to be a consequence of the interaction between the sensitivity of the hair-cell afferent synapse and the nonlinear, compressive growth of the cochlear amplifier that enhances mechanical vibrations on the basilar membrane. Little is known, however, about the cochlear amplifier in other vertebrate species. Rate-intensity functions were recorded from auditory-nerve fibers in chicks of the emu, a member of the Ratites, a primitive group of flightless birds that have poorly differentiated short and tall hair cells. Recorded data were found to be well fitted by analytical functions which have previously been shown to represent well the shapes of rate-intensity functions in guinea pigs. At the fibers' most sensitive frequencies, rate-intensity functions were almost exclusively of the sloping (80.9%) or straight (18.6%) type. Flat-saturating functions, the most common type in the mammal, represented only about 0.5% of the total in the emu. Below the best frequency of each fiber, the rate-intensity functions tended more towards the flat-saturating type, as is the case in mammals; a similar but weaker trend was seen above best frequency in most fibers, with only a small proportion (18%) showing the reverse trend. The emu rate-intensity functions were accepted as supporting previous evidence for the existence of a cochlear amplifier in birds, the conclusion was drawn further that the nonlinearity observed is probably due to saturation of the hair-cell transduction mechanism. PMID:10790040

Yates, G K; Manley, G A; Köppl, C

2000-04-01

112

Experimental strategies to promote functional recovery after peripheral nerve injuries.  

PubMed

The capacity of Schwann cells (SCs) in the peripheral nervous system to support axonal regeneration, in contrast to the oligodendrocytes in the central nervous system, has led to the misconception that peripheral nerve regeneration always restores function. Here, we consider how prolonged periods of time that injured neurons remain without targets during axonal regeneration (chronic axotomy) and that SCs in the distal nerve stumps remain chronically denervated (chronic denervation) progressively reduce the number of motoneurons that regenerate their axons. We demonstrate the effectiveness of low-dose, brain-derived neurotrophic and glial-derived neurotrophic factors to counteract the effects of chronic axotomy in promoting axonal regeneration. High-dose brain-derived neurotrophic factor (BDNF) on the other hand, acting through the p75 receptor, inhibits axonal regeneration and may be a factor in stopping regenerating axons from forming neuromuscular connections in skeletal muscle. The immunophilin, FK506, is also effective in promoting axonal regeneration after chronic axotomy. Chronic denervation of SCs (>1 month) severely deters axonal regeneration, although the few motor axons that do regenerate to reinnervate muscles become myelinated and form enlarged motor units in the reinnervated muscles. We found that in vitro incubation of chronically denervated SCs with transforming growth factor-beta re-established their growth-supportive phenotype in vivo, consistent with the idea that the interaction between invading macrophages and denervated SCs during Wallerian degeneration is essential to sustain axonal regeneration by promoting the growth-supportive SC phenotype. Finally, we consider the effectiveness of a brief period of 20 Hz electrical stimulation in promoting the regeneration of axons across the surgical gap after nerve repair. PMID:14641648

Gordon, Tessa; Sulaiman, Olawale; Boyd, J Gordon

2003-12-01

113

Sensory ability in the narwhal tooth organ system.  

PubMed

The erupted tusk of the narwhal exhibits sensory ability. The hypothesized sensory pathway begins with ocean water entering through cementum channels to a network of patent dentinal tubules extending from the dentinocementum junction to the inner pulpal wall. Circumpulpal sensory structures then signal pulpal nerves terminating near the base of the tusk. The maxillary division of the fifth cranial nerve then transmits this sensory information to the brain. This sensory pathway was first described in published results of patent dentinal tubules, and evidence from dissection of tusk nerve connection via the maxillary division of the fifth cranial nerve to the brain. New evidence presented here indicates that the patent dentinal tubules communicate with open channels through a porous cementum from the ocean environment. The ability of pulpal tissue to react to external stimuli is supported by immunohistochemical detection of neuronal markers in the pulp and gene expression of pulpal sensory nerve tissue. Final confirmation of sensory ability is demonstrated by significant changes in heart rate when alternating solutions of high-salt and fresh water are exposed to the external tusk surface. Additional supporting information for function includes new observations of dentinal tubule networks evident in unerupted tusks, female erupted tusks, and vestigial teeth. New findings of sexual foraging divergence documented by stable isotope and fatty acid results add to the discussion of the functional significance of the narwhal tusk. The combined evidence suggests multiple tusk functions may have driven the tooth organ system's evolutionary development and persistence. PMID:24639076

Nweeia, Martin T; Eichmiller, Frederick C; Hauschka, Peter V; Donahue, Gretchen A; Orr, Jack R; Ferguson, Steven H; Watt, Cortney A; Mead, James G; Potter, Charles W; Dietz, Rune; Giuseppetti, Anthony A; Black, Sandie R; Trachtenberg, Alexander J; Kuo, Winston P

2014-04-01

114

CAN SENSORY AND MOTOR COLLATERAL SPROUTING BE INDUCED FROM INTACT PERIPHERAL NERVE BY END-TO-SIDE ANASTOMOSIS?  

Microsoft Academic Search

The possibility that collateral sprouting could occur from intact axons in an undamaged sciatic nerve was studied in the rat by suturing either a 7-day predegenerated or a fresh nerve segment in an end-to-side fashion to the sciatic nerve proper. Following a 14- or 35-day recovery period, the pinch reflex test was performed on the transplanted segment to demonstrate the

G. LUNDBORG; Q. ZHAO; M. KANJE; N. DANIELSEN; J. M. KERNS

1994-01-01

115

Ipsilateral facial sensory and motor responses to basal fronto-temporal cortical stimulation: Evidence suggesting direct activation of cranial nerves  

Microsoft Academic Search

To clarify the generator mechanism of sensory and motor facial responses ipsilateral to electrical stimulation of the inferior fronto-temporal cortex in epilepsy patients. Out of 30 patients who have been evaluated with chronically implanted subdural electrodes for medically intractable partial seizure or brain tumor involving the basal frontal or temporal cortex, 4 patients (age ranging 24–57 years) showed sensory and

Tahamina Begum; Akio Ikeda; Masao Matsuhashi; Nobuhiro Mikuni; Susumu Miyamoto; Nobuo Hashimoto; Takashi Nagamine; Hidenao Fukuyama; Hiroshi Shibasaki

2006-01-01

116

Preserved sensory-motor function despite large-scale morphological alterations in a series of patients with holocord syringomyelia.  

PubMed

Although the central nervous system has a limited capacity for regeneration after acute brain and spinal cord injuries, it can reveal extensive morphological changes. Occasionally the formation of an extensive syrinx in the spinal cord can be observed causing no or only limited signs of functional impairment. This creates a unique condition to evaluate the mismatch between substantial morphological changes and functional outcomes. 7 patients with holocord syringomyelia affecting the cervical cord following chronic traumatic thoracic/lumbar spinal cord injury (19 - 34 years after injury) or of non-traumatic origin were identified and anatomical syrinx dimensions (length, cross-sectional area) were determined using sagittal and axial MRI scans. Motor- and sensory-pathway integrity were evaluated using electrophysiological assessments (motor (MEP), sensory (dSSEP) and contact-heat (dCHEP) evoked potentials; nerve conduction studies (NCS)) and specifically compared to clinical measures of upper limb strength and grasping performance including 3-D motion analysis. Despite extensive anatomical changes of the cervical cord (on average 26% reduction of residual spinal cord area and intrusion of almost the entire cervical spinal cord) a clinically relevant impairment of upper limb motor function was absent while only subtle sensory deficits could be detected. dCHEPs revealed the highest sensitivity by disclosing impairments of spinothalamic pathways. Comparable to the brain extensive anatomical changes of the spinal cord can occur with only subtle functional impairment. Obviously, the time scale of very slowly emerging morphological alterations is essential to permit an enormous capacity for plasticity of the spinal cord. PMID:25219978

Awai, Lea; Curt, Armin

2014-09-15

117

A Silicon Model of Auditory-Nerve Response Nonlinear signal processing is an integral part of sensory transduction in  

E-print Network

intensities to a manageable excursion of signal level. Spiral-ganglion neurons connect to each inner hair cell of an auditory-nerve fiber can encode only about 25 dB of sound intensity. Humans can sense binaural time5 Chapter 2 A Silicon Model of Auditory-Nerve Response Nonlinear signal processing is an integral

Lazzaro, John

118

Electrical Stimulation as a Therapeutic Option to Improve Eyelid Function in Chronic Facial Nerve Disorders  

Microsoft Academic Search

PURPOSE. TO establish whether it is possible to improve orbicularis oculi muscle function in the eyelids of patients with a chronic seventh cranial nerve palsy by using transcutaneous electrical stimulation to the point at which electrical stimulation induces a functional blink. METHODS. Ten subjects (one woman, nine men) aged 36 to 76 with chronic, moderate to severe facial nerve palsy

John Gittins; Kevin Martin; James Sbeldrick; Ashwin Reddy; Leonard Tbean

119

Nerve Growth Factor Mediates a Switch in Intracellular Signaling for PGE2-Induced Sensitization of Sensory Neurons from Protein Kinase A to Epac  

PubMed Central

We examined whether nerve growth factor (NGF), an inflammatory mediator that contributes to chronic hypersensitivity, alters the intracellular signaling that mediates the sensitizing actions of PGE2 from activation of protein kinase A (PKA) to exchange proteins directly activated by cAMP (Epacs). When isolated sensory neurons are grown in the absence of added NGF, but not in cultures grown with 30 ng/ml NGF, inhibiting protein kinase A (PKA) activity blocks the ability of PGE2 to augment capsaicin-evoked release of the neuropeptide CGRP and to increase the number of action potentials (APs) evoked by a ramp of current. Growing sensory neurons in culture in the presence of increasing concentrations of NGF increases the expression of Epac2, but not Epac1. An intradermal injection of complete Freund's adjuvant into the rat hindpaw also increases the expression of Epac2, but not Epac1 in the dorsal root ganglia and spinal cord: an effect blocked by intraplantar administration of NGF antibodies. Treating cultures grown in the presence of 30 ng/ml NGF with Epac1siRNA significantly reduced the expression of Epac1, but not Epac2, and did not block the ability of PGE2 to augment capsaicin-evoked release of CGRP from sensory neurons. Exposing neuronal cultures grown in NGF to Epac2siRNAreduced the expression of Epac2, but not Epac1 and prevented the PGE2-induced augmentation of capsaicin and potassium-evoked CGRP release in sensory neurons and the PGE2-induced increase in the number of APs generated by a ramp of current. In neurons grown with no added NGF, Epac siRNAs did not attenuate PGE2-induced sensitization. These results demonstrate that NGF, through increasing Epac2 expression, alters the signaling cascade that mediates PGE2-induced sensitization of sensory neurons, thus providing a novel mechanism for maintaining PGE2-induced hypersensitivity during inflammation. PMID:25126967

Vasko, Michael R.; Habashy Malty, Ramy; Guo, Chunlu; Duarte, Djane B.; Zhang, Yihong; Nicol, Grant D.

2014-01-01

120

Transplantation of embryonic motor neurons into peripheral nerve combined with functional electrical stimulation restores functional muscle activity in the rat sciatic nerve transection model.  

PubMed

Reinnervation of denervated muscle by motor neurons transplanted into the peripheral nerve may provide the potential to excite muscles artificially with functional electrical stimulation (FES). Here we investigated whether transplantation of embryonic motor neurons into peripheral nerve combined with FES restored functional muscle activity in adult Fischer 344 rats after transection of the sciatic nerve. One week after sciatic nerve transection, cell culture medium containing (cell transplantation group, n?=?6) or lacking (surgical control group, n?=?6) dissociated embryonic spinal neurons was injected into the distal stump of the tibial and peroneal nerves. Electrophysiological and tissue analyses were performed in the cell transplantation and surgical control groups 12?weeks after transplantation, as well as a in naïve control group (n?=?6) that received no surgery. In the cell transplantation group, ankle angle was measured during gait, with and without FES of the peroneal nerve. Ankle angle at mid-swing was more flexed during gait with FES (26.6?±?8.7°) than gait without FES (51.4?±?12.8°, p?=?0.011), indicating that transplantated motor neurons in conjunction with FES restored ankle flexion in gait, even though no neural connection between central nervous system and muscle was present. These results indicate that transplantation of embryonic motor neurons into peripheral nerve combined with FES can provide a novel treatment strategy for paralysed muscles. Copyright © 2013 John Wiley & Sons, Ltd. PMID:24668934

Kurimoto, Shigeru; Kato, Shuichi; Nakano, Tomonori; Yamamoto, Michiro; Takanobu, Nishizuka; Hirata, Hitoshi

2013-10-30

121

Analysis of osm-6, a gene that affects sensory cilium structure and sensory neuron function in Caenorhabditis elegans.  

PubMed Central

Mutation in the Caenorhabditis elegans gene osm-6 was previously shown to result in defects in the ultrastructure of sensory cilia and defects in chemosensory and mechanosensory behaviors. We have cloned osm-6 by transposon tagging and transformation rescue and have identified molecular lesions associated with five osm-6 mutations. The osm-6 gene encodes a protein that is 40% identical in amino acid sequence to a predicted mammalian protein of unknown function. We fused osm-6 with the gene for green fluorescent protein (GFP); the fusion gene rescued the osm-6 mutant phenotype and showed accumulation of GFP in ciliated sensory neurons exclusively. The OSM-6::GFP protein was localized to cytoplasm, including processes and dendritic endings where sensory cilia are situated. Mutations in other genes known to cause ciliary defects led to changes in the appearance of OSM-6::GFP in dendritic endings or, in the case of daf-19, reduced OSM-6::GFP accumulation. We conclude from an analysis of genetic mosaics that osm-6 acts cell autonomously in affecting cilium structure. PMID:9475731

Collet, J; Spike, C A; Lundquist, E A; Shaw, J E; Herman, R K

1998-01-01

122

Sensory fusion in Physarum polycephalum and implementing multi-sensory functional computation.  

PubMed

Surface electrical potential and observational growth recordings were made of a protoplasmic tube of the slime mould Physarum polycephalum in response to a multitude of stimuli with regards to sensory fusion or multisensory integration. Each stimulus was tested alone and in combination in order to evaluate for the first time the effect that multiple stimuli have on the frequency of streaming oscillation. White light caused a decrease in frequency whilst increasing the temperature and applying a food source in the form of oat flakes both increased the frequency. Simultaneously stimulating P. polycephalum with light and oat flake produced no net change in frequency, while combined light and heat stimuli showed an increase in frequency smaller than that observed for heat alone. When the two positive stimuli, oat flakes and heat, were combined, there was a net increase in frequency similar to the cumulative increases caused by the individual stimuli. Boolean logic gates were derived from the measured frequency change. PMID:24695059

Whiting, James G H; de Lacy Costello, Ben P J; Adamatzky, Andrew

2014-05-01

123

Sensory regulation of dopaminergic cell activity: Phenomenology, circuitry and function.  

PubMed

Dopaminergic neurons in a range of species are responsive to sensory stimuli. In the anesthetized preparation, responses to non-noxious and noxious sensory stimuli are usually tonic in nature, although long-duration changes in activity have been reported in the awake preparation as well. However, in the awake preparation, short-latency, phasic changes in activity are most common. These phasic responses can occur to unconditioned aversive and non-aversive stimuli, as well as to the stimuli which predict them. In both the anesthetized and awake preparations, not all dopaminergic neurons are responsive to sensory stimuli, however responsive neurons tend to respond to more than a single stimulus modality. Evidence suggests that short-latency sensory information is provided to dopaminergic neurons by relatively primitive subcortical structures - including the midbrain superior colliculus for vision and the mesopontine parabrachial nucleus for pain and possibly gustation. Although short-latency visual information is provided to dopaminergic neurons by the relatively primitive colliculus, dopaminergic neurons can discriminate between complex visual stimuli, an apparent paradox which can be resolved by the recently discovered route of information flow through to dopaminergic neurons from the cerebral cortex, via a relay in the colliculus. Given that projections from the cortex to the colliculus are extensive, such a relay potentially allows the activity of dopaminergic neurons to report the results of complex stimulus processing from widespread areas of the cortex. Furthermore, dopaminergic neurons could acquire their ability to reflect stimulus value by virtue of reward-related modification of sensory processing in the cortex. At the forebrain level, sensory-related changes in the tonic activity of dopaminergic neurons may regulate the impact of the cortex on forebrain structures such as the nucleus accumbens. In contrast, the short latency of the phasic responses to sensory stimuli in dopaminergic neurons, coupled with the activation of these neurons by non-rewarding stimuli, suggests that phasic responses of dopaminergic neurons may provide a signal to the forebrain which indicates that a salient event has occurred (and possibly an estimate of how salient that event is). A stimulus-related salience signal could be used by downstream systems to reinforce behavioral choices. PMID:24462607

Overton, P G; Vautrelle, N; Redgrave, P

2014-01-23

124

Genetic inactivation and pharmacological blockade of sigma-1 receptors prevent paclitaxel-induced sensory-nerve mitochondrial abnormalities and neuropathic pain in mice  

PubMed Central

Background Paclitaxel, a widely-used antineoplastic drug, produces a painful peripheral neuropathy that in rodents is associated with peripheral-nerve mitochondrial alterations. The sigma-1 receptor (?1R) is a ligand-regulated molecular chaperone involved in mitochondrial calcium homeostasis and pain hypersensitivity. This receptor plays a key role in paclitaxel-induced neuropathic pain, but it is not known whether it also modulates mitochondrial abnormalities. In this study, we used a mouse model of paclitaxel-induced neuropathic pain to test the involvement of the ?1R in the mitochondrial abnormalities associated with paclitaxel, by using genetic (?1R knockout mice) and pharmacological (?1R antagonist) approaches. Results Paclitaxel administration to wild-type (WT) mice produced cold- and mechanical-allodynia, and an increase in the frequency of swollen and vacuolated mitochondria in myelinated A-fibers, but not in C-fibers, of the saphenous nerve. Behavioral and mitochondrial alterations were marked at 10 days after paclitaxel-administration and had resolved at day 28. In contrast, paclitaxel treatment did not induce allodynia or mitochondrial abnormalities in ?1R knockout mice. Moreover, the prophylactic treatment of WT mice with BD-1063 also prevented the neuropathic pain and mitochondrial abnormalities induced by paclitaxel. Conclusions These results suggest that activation of the ?1R is necessary for development of the sensory nerve mitochondrial damage and neuropathic pain produced by paclitaxel. Therefore, ?1R antagonists might have therapeutic value for the prevention of paclitaxel-induced neuropathy. PMID:24517272

2014-01-01

125

CHARACTERIZATION & TREATMENT OF LARGE SENSORY FIBER PERIPHERAL NEUROPATHY IN DIABETIC MICE  

E-print Network

Patients with large-fiber diabetic sensorimotor polyneuropathy (DPN) can develop altered sensorimotor function. Gait and balance control are regulated, in part, through large sensory nerves innervating muscle spindles. The overall goal...

Muller, Karra

2008-11-17

126

L-carnitine alleviates sciatic nerve crush injury in rats: functional and electron microscopy assessments  

PubMed Central

Several studies have demonstrated that L-carnitine exhibits neuroprotective effects on injured sciatic nerve of rats with diabetes mellitus. It is hypothesized that L-carnitine exhibits neuroprotective effects on injured sciatic nerve of rats. Rat sciatic nerve was crush injured by a forceps and exhibited degenerative changes. After intragastric administration of 50 and 100 mg/kg L-carnitine for 30 days, axon area, myelin sheath area, axon diameter, myelin sheath diameter, and numerical density of the myelinated axons of injured sciatic nerve were similar to normal, and the function of injured sciatic nerve also improved significantly. These findings suggest that L-carnitine exhibits neuroprotective effects on sciatic nerve crush injury in rats. PMID:25206754

Avsar, Ümmü Zeynep; Avsar, Umit; Aydin, Ali; Yayla, Muhammed; Ozturkkaragoz, Berna; Un, Harun; Saritemur, Murat; Mercantepe, Tolga

2014-01-01

127

Analysis of trigeminal nerve disorders after oral and maxillofacial intervention  

PubMed Central

Background Quantitative sensory testing (QST) is applied to evaluate somatosensory nerve fiber function in the spinal system. This study uses QST in patients with sensory dysfunctions after oral and maxillofacial surgery. Methods Orofacial sensory functions were investigated by psychophysical means in 60 volunteers (30 patients with sensory disturbances and 30 control subjects) in innervation areas of the infraorbital, mental and lingual nerves. The patients were tested 1 week, 4 weeks, 7 weeks and 10 weeks following oral and maxillofacial surgery. Results QST monitored somatosensory deficits and recovery of trigeminal nerve functions in all patients. Significant differences (p < 0.05) between control group and patients were shown for cold, warm and mechanical detection thresholds and for cold, heat and mechanical pain thresholds. Additionally, QST monitored recovery of nerve functions in all patients. Conclusion QST can be applied for non-invasive assessment of sensory nerve function (A?-, A?- and C-fiber) in the orofacial region and is useful in the diagnosis of trigeminal nerve disorders in patients. PMID:20977760

2010-01-01

128

Restoration of visual function following optic nerve regeneration in bluegill ~Lepomis macrochirus!  

E-print Network

Restoration of visual function following optic nerve regeneration in bluegill ~Lepomis macrochirus ~Lepomis macrochirus! pumpkinseed ~Lepomis gibbosus! hybrid sunfish. Regenerating optic nerve axons! pumpkinseed ~Lepomis gibbosus! hybrid sunfish MICHAEL P. CALLAHAN1,2 and ALLEN F. MENSINGER1 1 Department

Mensinger, Allen F.

129

Clinical Strategies to Enhance Nerve Regeneration in Composite Tissue Allotransplantation  

PubMed Central

Synopsis Reinnervation of a hand transplant ultimately dictates functional recovery but provides a significant regenerative challenge. The authors present a review highlighting interventions to enhance nerve regeneration through acceleration of axonal regeneration or augmentation of Schwann cell supportand discuss their relevance to composite tissue allotransplantation. Surgical techniques that may be performed at the time of transplantation to optimize intrinsic muscle recovery—including appropriate alignment of ulnar nerve motor and sensory components, transfer of the distal anterior interosseous nerve to the recurrent motor branch of the median nerve, and prophylactic release of potential nerve entrapment points—are also presented. PMID:22051390

Glaus, Simone W.; Johnson, Philip J.; Mackinnon, Susan E.

2011-01-01

130

The Trigeminal (V) and Facial (VII) Cranial Nerves  

PubMed Central

There are close functional and anatomical relationships between cranial nerves V and VII in both their sensory and motor divisions. Sensation on the face is innervated by the trigeminal nerves (V) as are the muscles of mastication, but the muscles of facial expression are innervated mainly by the facial nerve (VII) as is the sensation of taste. This article briefly reviews the anatomy of these cranial nerves, disorders of these nerves that are of particular importance to psychiatry, and some considerations for differential diagnosis. PMID:20386632

Sanders, Richard D.

2010-01-01

131

3D multi-channel bi-functionalized silk electrospun conduits for peripheral nerve regeneration.  

PubMed

Despite technological advances over the past 25 years, a complete recovery from peripheral nerve injuries remains unsatisfactory today. The autograft is still considered the "gold standard" in clinical practice; however, postoperative complications and limited availability of nerve tissue have motivated the development of alternative approaches. Among them, the development of biomimetic nerve graft substitutes is one of the most promising strategies. In this study, multichanneled silk electrospun conduits bi-functionalized with Nerve Growth Factor (NGF) and Ciliary Neurotropic Factor (CNTF) were fabricated to enhance peripheral nerve regeneration. These bioactive guides consisting of longitudinally oriented channels and aligned nanofibers were designed in order to mimic the fascicular architecture and fibrous extracellular matrix found in native nerve. The simple use of the electrospinning technique followed by a manual manipulation to manufacture these conduits provides tailoring of channel number and diameter size to create perineurium-like structures. Functionalization of the silk fibroin nanofiber did not affect its secondary structure and chemical property. ELISA assays showed the absence of growth factors passive release from the functionalized fibers avoiding the topical accumulation of proteins. In addition, our biomimetic multichanneled functionalized nerve guides displayed a mechanical behavior comparable to that of rat sciatic nerve with an ultimate peak stress of 4.0 ± 0.6 MPa and a corresponding elongation at failure of 156.8 ± 46.7%. Taken together, our results demonstrate for the first time our ability to design and characterize a bi-functionalized nerve conduit consisting of electrospun nanofibers with multichannel oriented and nanofibers aligned for peripheral regeneration. Our bioactive silk tubes thus represent a new and promising technique towards the creation of a biocompatible nerve guidance conduit. PMID:25460402

Dinis, T M; Elia, R; Vidal, G; Dermigny, Q; Denoeud, C; Kaplan, D L; Egles, C; Marin, F

2015-01-01

132

Peripheral nerve regeneration through collagen devices with different in vivo degradation characteristics  

E-print Network

In the United States more than 200,000 people are treated each year for peripheral nerve injuries that require surgery. Functional recovery of motor and sensory capability is limited following autograft, the most common ...

Harley, Brendan A. (Brendan Andrew), 1978-

2002-01-01

133

A bioengineered peripheral nerve construct using aligned peptide amphiphile nanofibers.  

PubMed

Peripheral nerve injuries can result in lifelong disability. Primary coaptation is the treatment of choice when the gap between transected nerve ends is short. Long nerve gaps seen in more complex injuries often require autologous nerve grafts or nerve conduits implemented into the repair. Nerve grafts, however, cause morbidity and functional loss at donor sites, which are limited in number. Nerve conduits, in turn, lack an internal scaffold to support and guide axonal regeneration, resulting in decreased efficacy over longer nerve gap lengths. By comparison, peptide amphiphiles (PAs) are molecules that can self-assemble into nanofibers, which can be aligned to mimic the native architecture of peripheral nerve. As such, they represent a potential substrate for use in a bioengineered nerve graft substitute. To examine this, we cultured Schwann cells with bioactive PAs (RGDS-PA, IKVAV-PA) to determine their ability to attach to and proliferate within the biomaterial. Next, we devised a PA construct for use in a peripheral nerve critical sized defect model. Rat sciatic nerve defects were created and reconstructed with autologous nerve, PLGA conduits filled with various forms of aligned PAs, or left unrepaired. Motor and sensory recovery were determined and compared among groups. Our results demonstrate that Schwann cells are able to adhere to and proliferate in aligned PA gels, with greater efficacy in bioactive PAs compared to the backbone-PA alone. In vivo testing revealed recovery of motor and sensory function in animals treated with conduit/PA constructs comparable to animals treated with autologous nerve grafts. Functional recovery in conduit/PA and autologous graft groups was significantly faster than in animals treated with empty PLGA conduits. Histological examinations also demonstrated increased axonal and Schwann cell regeneration within the reconstructed nerve gap in animals treated with conduit/PA constructs. These results indicate that PA nanofibers may represent a promising biomaterial for use in bioengineered peripheral nerve repair. PMID:25064803

Li, Andrew; Hokugo, Akishige; Yalom, Anisa; Berns, Eric J; Stephanopoulos, Nicholas; McClendon, Mark T; Segovia, Luis A; Spigelman, Igor; Stupp, Samuel I; Jarrahy, Reza

2014-10-01

134

Spontaneous intraneural hematoma of the sural nerve.  

PubMed

Symptomatic intraneural hemorrhage occurs rarely. It presents with pain and/or weakness in the distribution following the anatomic innervation pattern of the involved nerve. When a purely sensory nerve is affected, the symptoms can be subtle. We present a previously healthy 36-year-old female who developed an atraumatic, spontaneous intraneural hematoma of her sural nerve. Sural dysfunction was elicited from the patient's history and physical examination. The diagnosis was confirmed with magnetic resonance imaging, and surgical decompression provided successful resolution of her preoperative symptoms. To our knowledge, this entity has not been reported previously. Our case highlights the importance of having a high index of suspicion for nerve injury or compression in patients whose complaints follow a typical peripheral nerve distribution. Prior studies have shown that the formation of intraneural hematoma and associated compression of nerve fibers result in axonal degeneration, and surgical decompression decreases axonal degeneration and aids functional recovery. PMID:25311865

Richardson, Shawn S; McLawhorn, Alexander S; Mintz, Douglas N; DiCarlo, Edward F; Weiland, Andrew J

2015-04-01

135

An unusual cause of radial nerve palsy.  

PubMed

Neurapraxia frequently occurs following traction injury to the nerve intraoperatively, leading to radial nerve palsy which usually recovers in 5-30 weeks. In our case, we had operated a distal one-third of humeral shaft fracture and fixed it with 4.5 mm limited contact dynamic compression plate. The distal neurovascular status of the limb was assessed postoperatively in the recovery room and was found to be intact and all the sensory-motor functions of the radial nerve were normal. On the second postoperative day, following the suction drain removal and dressing, patient developed immediate radial nerve palsy along with wrist drop. We reviewed the literature and found no obvious cause for the nerve palsy and concluded that it was due to traction injury to the radial nerve while removing the suction drain in negative pressure. PMID:24889983

Agrawal, Hemendra Kumar; Khatkar, Vipin; Garg, Mohit; Singh, Balvinder; Jaiman, Ashish; Sharma, Vinod Kumar

2014-06-01

136

Differential upregulation in DRG neurons of an ?2?-1 splice variant with a lower affinity for gabapentin after peripheral sensory nerve injury  

PubMed Central

The ?2?-1 protein is an auxiliary subunit of voltage-gated calcium channels, critical for neurotransmitter release. It is upregulated in dorsal root ganglion (DRG) neurons following sensory nerve injury, and is also the therapeutic target of the gabapentinoid drugs, which are efficacious in both experimental and human neuropathic pain conditions. ?2?-1 has 3 spliced regions: A, B, and C. A and C are cassette exons, whereas B is introduced via an alternative 3? splice acceptor site. Here we have examined the presence of ?2?-1 splice variants in DRG neurons, and have found that although the main ?2?-1 splice variant in DRG is the same as that in brain (?2?-1 ?A+B+C), there is also another ?2?-1 splice variant (?A+B?C), which is expressed in DRG neurons and is differentially upregulated compared to the main DRG splice variant ?2?-1 ?A+B+C following spinal nerve ligation. Furthermore, this differential upregulation occurs preferentially in a small nonmyelinated DRG neuron fraction, obtained by density gradient separation. The ?2?-1 ?A+B?C splice variant supports CaV2 calcium currents with unaltered properties compared to ?2?-1 ?A+B+C, but shows a significantly reduced affinity for gabapentin. This variant could therefore play a role in determining the efficacy of gabapentin in neuropathic pain. PMID:24315988

Lana, Beatrice; Schlick, Bettina; Martin, Stuart; Pratt, Wendy S.; Page, Karen M.; Goncalves, Leonor; Rahman, Wahida; Dickenson, Anthony H.; Bauer, Claudia S.; Dolphin, Annette C.

2014-01-01

137

Altered rectal sensory response induced by balloon distention in patients with functional abdominal pain syndrome  

Microsoft Academic Search

BACKGROUND: Functional abdominal pain syndrome (FAPS) has chronic unexplained abdominal pain and is similar to the psychiatric diagnosis of somatoform pain disorder. A patient with irritable bowel syndrome (IBS) also has chronic unexplained abdominal pain, and rectal hypersensitivity is observed in a majority of the patients. However, no reports have evaluated the visceral sensory function of FAPS precisely. We aimed

Tsukasa Nozu; Miwako Kudaira

2009-01-01

138

Ketoprofen combined with artery graft entubulization improves functional recovery of transected peripheral nerves.  

PubMed

The objective was to assess the local effect of ketoprofen on sciatic nerve regeneration and functional recovery. Eighty healthy male white Wistar rats were randomized into four experimental groups of 20 animals each: In the transected group (TC), the left sciatic nerve was transected and nerve cut ends were fixed in the adjacent muscle. In the treatment group the defect was bridged using an artery graft (AG/Keto) filled with 10 microliter ketoprofen (0.1 mg/kg). In the artery graft group (AG), the graft was filled with phosphated-buffer saline alone. In the sham-operated group (SHAM), the sciatic nerve was exposed and manipulated. Each group was subdivided into four subgroups of five animals each and regenerated nerve fibres were studied at 4, 8, 12 and 16 weeks post operation. Behavioural testing, sciatic nerve functional study, gastrocnemius muscle mass and morphometric indices showed earlier regeneration of axons in AG/Keto than in AG group (p < 0.05). Immunohistochemical study clearly showed more positive location of reactions to S-100 in AG/Keto than in AG group. When loaded in an artery graft, ketoprofen improved functional recovery and morphometric indices of the sciatic nerve. Local usage of this easily accessible therapeutic medicine is cost saving and avoids the problems associated with systemic administration. PMID:23932540

Mohammadi, Rahim; Mehrtash, Moein; Nikonam, Nima; Mehrtash, Moied; Amini, Keyvan

2014-12-01

139

Conventional and Functional MR Imaging of Peripheral Nerve Sheath Tumors: Initial Experience  

PubMed Central

BACKGROUND AND PURPOSE Differentiating benign from malignant peripheral nerve sheath tumors can be very challenging using conventional MR imaging. Our aim was to test the hypothesis that conventional and functional MR imaging can accurately diagnose malignancy in patients with indeterminate peripheral nerve sheath tumors. MATERIALS AND METHODS This institutional review board–approved, Health Insurance Portability and Accountability Act–compliant study retrospectively reviewed 61 consecutive patients with 80 indeterminate peripheral nerve sheath tumors. Of these, 31 histologically proved peripheral nerve sheath tumors imaged with conventional (unenhanced T1, fluid-sensitive, contrast-enhanced T1-weighted sequences) and functional MR imaging (DWI/apparent diffusion coefficient mapping, dynamic contrast-enhanced MR imaging) were included. Two observers independently assessed anatomic (size, morphology, signal) and functional (ADC values, early arterial enhancement by dynamic contrast-enhanced MR) features to determine interobserver agreement. The accuracy of MR imaging for differentiating malignant from benign was also determined by receiver operating characteristic analysis. RESULTS Of 31 peripheral nerve sheath tumors, there were 9 malignant (9%) and 22 benign ones (81%). With anatomic sequences, average tumor diameter (6.3 ± 1.8 versus 3.9 ± 2.3 mm, P = .009), ill-defined/infiltrative margins (77% versus 32%; P = .04), and the presence of peritumoral edema (66% versus 23%, P = .01) were different for malignant peripheral nerve sheath tumors and benign peripheral nerve sheath tumors. With functional sequences, minimum ADC (0.47 ± 0.32 × 10?3 mm2/s versus 1.08 ± 0.26 × 10?3 mm2/s; P [H11021] .0001) and the presence of early arterial enhancement (50% versus 11%; P = .03) were different for malignant peripheral nerve sheath tumors and benign peripheral nerve sheath tumors. The minimum ADC (area under receiver operating characteristic curve was 0.89; 95% confidence interval, 0.73– 0.97) and the average tumor diameter (area under the curve = 0.8; 95% CI, 0.66 – 0.94) were accurate in differentiating malignant peripheral nerve sheath tumors from benign peripheral nerve sheath tumors. With threshold values for minimum ADC ? 1.0 × 10?3 mm2/s and an average diameter of ?4.2 cm, malignancy could be diagnosed with 100% sensitivity (95% CI, 66.4%–100%). CONCLUSIONS Average tumor diameter and minimum ADC values are potentially important parameters that may be used to distinguish malignant peripheral nerve sheath tumors from benign peripheral nerve sheath tumors. PMID:24763412

Demehri, S.; Belzberg, A.; Blakeley, J.; Fayad, L.M.

2015-01-01

140

Extensive Sprouting of Sensory Afferents and Hyperalgesia Induced by Conditional Expression of Nerve Growth Factor in the Adult Spinal Cord  

Microsoft Academic Search

Genetic transfer of growth-promoting molecules was proposed as a potential strategy to modify the nonpermissive nature of the adult CNS to induce axonal regeneration. To evaluate whether overexpression of neurotrophins or cellular adhesion molecules would effect axonal plasticity, adenoviruses encod- ing fibroblast growth factor-2 (FGF-2\\/Adts), nerve growth factor (NGF\\/Adts), neurotrophin-3, and the cell adhesion molecules N-cadherin and L1 were injected

Mario I. Romero; Nagarathnamma Rangappa; Li Li; Ellis Lightfoot; Mary G. Garry; George M. Smith

2000-01-01

141

Upregulation of Bradykinin B2 Receptor Expression by Neurotrophic Factors and Nerve Injury in Mouse Sensory Neurons  

Microsoft Academic Search

Bradykinin B2 receptor mRNA was detected at low levels, both by RT-PCR and by in situ hybridization, in freshly isolated dorsal root ganglia (DRG) and in ganglia cultured in the absence of neurotrophic factors, but was strongly upregulated by culture in the presence of nerve growth factor (NGF). The effect of NGF is mediated via TrkA receptors. The related neurotrophins,

Yih-Jing Lee; Olof Zachrisson; David A. Tonge; Peter A. McNaughton

2002-01-01

142

Imaging of temperature dependent hemodynamics in the rat sciatic nerve by functional photoacoustic microscopy  

PubMed Central

Background Vascular hemodynamics is central to the regulation of neuro-metabolism and plays important roles in peripheral nerves diseases and their prevention. However, at present there are only a few techniques capable of directly measuring peripheral nerve vascular hemodynamics. Method Here, we investigate the use of dark-field functional photoacoustic microscopy (fPAM) for intrinsic visualizing of the relative hemodynamics of the rat sciatic nerve in response to localized temperature modulation (i.e., cooling and rewarming). Results and conclusion Our main results show that the relative functional total hemoglobin concentration (HbT) is more significantly correlated with localized temperature changes than the hemoglobin oxygen saturation (SO2) changes in the sciatic nerve. Our study also indicates that the relative HbT changes are better markers of neuronal activation than SO2 during nerve temperature changes. Our results show that fPAM is a promising candidate for in vivo imaging of peripheral nerve hemodynamics without the use of contrast agents. Additionally, this technique may shed light on the neuroprotective effect of hypothermia on peripheral nerves by visualizing their intrinsic hemodynamics. PMID:24245952

2013-01-01

143

Intrinsic and therapeutic factors determining the recovery of motor function after peripheral nerve transection.  

PubMed

Insufficient recovery after peripheral nerve injury has been attributed to (i) poor pathfinding of regrowing axons, (ii) excessive collateral axonal branching at the lesion site and (iii) polyneuronal innervation of the neuromuscular junctions (NMJ). The facial nerve transection model has been used initially to measure restoration of function after varying therapies and to examine the mechanisms underlying their effects. Since it is very difficult to control the navigation of several thousand axons, efforts concentrated on collateral branching and NMJ-polyinnervation. Treatment with antibodies against trophic factors to combat branching improved the precision of reinnervation, but had no positive effects on functional recovery. This suggested that polyneuronal reinnervation--rather than collateral branching--may be the critical limiting factor. The former could be reduced by pharmacological agents known to perturb microtubule assembly and was followed by recovery of function. Because muscle polyinnervation is activity-dependent and can be manipulated, attempts to design a clinically feasible therapy were performed by electrical stimulation or by soft tissue massage. Electrical stimulation applied to the transected facial nerve or to paralysed facial muscles did not improve vibrissal motor performance and failed to diminish polyinnervation. In contrast, gentle stroking of the paralysed muscles (vibrissal, orbicularis oculi, tongue musculature) resulted in full recovery of function. This manual stimulation was also effective after hypoglossal-facial nerve suture and after interpositional nerve grafting, but not after surgical reconstruction of the median nerve. All these findings raise hopes that clinically feasible and effective therapies could be soon designed and tested. PMID:21458252

Skouras, Emmanouil; Ozsoy, Umut; Sarikcioglu, Levent; Angelov, Doychin N

2011-07-01

144

Using multiple high-count electrode arrays in human median and ulnar nerves to restore sensorimotor function after previous transradial amputation of the hand.  

PubMed

Peripheral nerve interfaces that can record from and stimulate large numbers of different nerve fibers selectively and independently may help restore intuitive and effective motor and sensory function after hand amputation. To this end, and extending previous work in two subjects, two 100-electrode Utah Slanted Electrode Arrays (USEAs) were implanted for four weeks in the residual ulnar and median nerves of a 50-year-old male whose left, dominant hand had been amputated 21 years previously. Subsequent experiments involved 1) recording from USEAs for real-time control of a virtual prosthetic hand; 2) stimulation to evoke somatosensory percepts; and 3) closed-loop sensorimotor control. Overall, partial motor control and sensation were achieved using USEAs. 1) Isolated action potentials recorded from nerve motor fibers, although sparse at these distal implant sites, were activated during fictive movements of the phantom hand. Unlike in our previous two subjects, electromyographic (EMG) activity contributed to most online recordings and decodes, but was reduced in offline analyses using common average referencing. Online and offline Kalman-filter decodes of thresholded neural or EMG spikes independently controlled different digits of the virtual hand with one or two degrees of freedom. 2) Microstimulation through individual electrodes of the two USEAs evoked up to 106 different percepts, covering much of the phantom hand. The subject discriminated among five perceived stimulus locations, and between two somatosensory submodalities at a single location. 3) USEA-evoked percepts, mimicking contact with either a near or distal virtual target, were used to terminate movements of the virtual hand controlled with USEA recordings comprised wholly or mostly of EMG. These results further indicate that USEAs can help restore sensory and motor function after hand loss. PMID:25570369

Clark, Gregory A; Wendelken, Suzanne; Page, David M; Davis, Tyler; Wark, Heather A C; Normann, Richard A; Warren, David J; Hutchinson, Douglas T

2014-08-01

145

Beyond traditional approaches to understanding the functional role of neuromodulators in sensory cortices  

PubMed Central

Over the last two decades, a vast literature has described the influence of neuromodulatory systems on the responses of sensory cortex neurons (review in Gu, 2002; Edeline, 2003; Weinberger, 2003; Metherate, 2004, 2011). At the single cell level, facilitation of evoked responses, increases in signal-to-noise ratio, and improved functional properties of sensory cortex neurons have been reported in the visual, auditory, and somatosensory modality. At the map level, massive cortical reorganizations have been described when repeated activation of a neuromodulatory system are associated with a particular sensory stimulus. In reviewing our knowledge concerning the way the noradrenergic and cholinergic system control sensory cortices, I will point out that the differences between the protocols used to reveal these effects most likely reflect different assumptions concerning the role of the neuromodulators. More importantly, a gap still exists between the descriptions of neuromodulatory effects and the concepts that are currently applied to decipher the neural code operating in sensory cortices. Key examples that bring this gap into focus are the concept of cell assemblies and the role played by the spike timing precision (i.e., by the temporal organization of spike trains at the millisecond time-scale) which are now recognized as essential in sensory physiology but are rarely considered in experiments describing the role of neuromodulators in sensory cortices. Thus, I will suggest that several lines of research, particularly in the field of computational neurosciences, should help us to go beyond traditional approaches and, ultimately, to understand how neuromodulators impact on the cortical mechanisms underlying our perceptual abilities. PMID:22866031

Edeline, Jean-Marc

2012-01-01

146

Use of ultrasound and fluoroscopy guidance in percutaneous radiofrequency lesioning of the sensory branches of the femoral and obturator nerves.  

PubMed

Hip pain is a common condition that is often seen in patients with multiple comorbidities. Often surgery is not an option due to these comorbidities. Percutaneous radiofrequency lesioning of the articular branches of the obturator and femoral nerves is an alternative treatment for hip pain. Traditionally, fluoroscopy is used to guide needle placement. We report a case where a novel approach was used with ultrasound guidance to visualize vascular and soft tissue structures in real time. The use of ultrasound might help to guide the needle to avoid vascular complications due to anatomical variation between patients. PMID:23656575

Chaiban, Gassan; Paradis, Tyler; Atallah, Joseph

2014-04-01

147

A novel approach for evaluating nerve function in healthy elderly persons: A pilot study  

PubMed Central

Background Motor nerve function decreases with age and can cause abnormalities in motor function. Using newly designed methods, we used evoked electromyograms to evaluate change in motor nerve function. Material/Methods Motor function was assessed by grip strength, timed up-and-go test, 5-m normal walk, and 5-m fastest walk. In addition, motor nerve conduction velocity was calculated by measuring latency differences (NCV) in elderly and young subjects. We also investigated motor nerve conduction velocity by correlation coefficient (NCVCC) and the difference between NCV and NCVCC (DNCV). Results Significant differences were observed in the motor function of elderly and young persons in grip strength, the timed up-and-go test, and the 5-m fastest walk; however, no difference was observed in the 5-m normal walk test. NCVCC was lower than NCV in both elderly and young. The correlation coefficient peak of the NCVCC calculation was lower in elderly than in young. A negative correlation was observed between correlation coefficient peak and DNCV in elderly subjects. Conclusions NCVCC compares the overall shape of compound muscle action potential and reflects not only the fastest motor unit, but also the motor nerve conduction velocity of other motor unit components. A significant negative correlation between DNCV and the correlation coefficient peak was observed only in elderly subjects, suggesting that older individuals, including those that maintain a high level of physical strength, experience a loss of motor nerve function. Thus, changes in motor nerve function among elderly persons can potentially be further examined for clinical use. PMID:23624713

Nishihara, Ken; Kawai, Hisashi; Kanemura, Naohiko; Hara, Motohiko; Naruse, Hideo; Gomi, Toshiaki

2013-01-01

148

Functional Specialization of Sensory Cilia by an RFX Transcription Factor Isoform  

PubMed Central

In animals, RFX transcription factors govern ciliogenesis by binding to an X-box motif in the promoters of ciliogenic genes. In Caenorhabditis elegans, the sole RFX transcription factor (TF) daf-19 null mutant lacks all sensory cilia, fails to express many ciliogenic genes, and is defective in many sensory behaviors, including male mating. The daf-19c isoform is expressed in all ciliated sensory neurons and is necessary and sufficient for activating X-box containing ciliogenesis genes. Here, we describe the daf-19(n4132) mutant that is defective in expression of the sensory polycystic kidney disease (PKD) gene battery and male mating behavior, without affecting expression of ciliogenic genes or ciliogenesis. daf-19(n4132) disrupts expression of a new isoform, daf-19m (for function in male mating). daf-19m is expressed in male-specific PKD and core IL2 neurons via internal promoters and remote enhancer elements located in introns of the daf-19 genomic locus. daf-19m genetically programs the sensory functions of a subset of ciliated neurons, independent of daf-19c. In the male-specific HOB neuron, DAF-19M acts downstream of the zinc finger TF EGL-46, indicating that a TF cascade controls the PKD gene battery in this cell-type specific context. We conclude that the RFX TF DAF-19 regulates ciliogenesis via X-box containing ciliogenic genes and controls ciliary specialization by regulating non-X-box containing sensory genes. This study reveals a more extensive role for RFX TFs in generating fully functional cilia. PMID:20923979

Wang, Juan; Schwartz, Hillel T.; Barr, Maureen M.

2010-01-01

149

Human muscle–derived stem/progenitor cells promote functional murine peripheral nerve regeneration  

PubMed Central

Peripheral nerve injuries and neuropathies lead to profound functional deficits. Here, we have demonstrated that muscle-derived stem/progenitor cells (MDSPCs) isolated from adult human skeletal muscle (hMDSPCs) can adopt neuronal and glial phenotypes in vitro and ameliorate a critical-sized sciatic nerve injury and its associated defects in a murine model. Transplanted hMDSPCs surrounded the axonal growth cone, while hMDSPCs infiltrating the regenerating nerve differentiated into myelinating Schwann cells. Engraftment of hMDSPCs into the area of the damaged nerve promoted axonal regeneration, which led to functional recovery as measured by sustained gait improvement. Furthermore, no adverse effects were observed in these animals up to 18 months after transplantation. Following hMDSPC therapy, gastrocnemius muscles from mice exhibited substantially less muscle atrophy, an increase in muscle mass after denervation, and reorganization of motor endplates at the postsynaptic sites compared with those from PBS-treated mice. Evaluation of nerve defects in animals transplanted with vehicle-only or myoblast-like cells did not reveal histological or functional recovery. These data demonstrate the efficacy of hMDSPC-based therapy for peripheral nerve injury and suggest that hMDSPC transplantation has potential to be translated for use in human neuropathies. PMID:24642464

Lavasani, Mitra; Thompson, Seth D.; Pollett, Jonathan B.; Usas, Arvydas; Lu, Aiping; Stolz, Donna B.; Clark, Katherine A.; Sun, Bin; Péault, Bruno; Huard, Johnny

2014-01-01

150

Sensory roles of neuronal cilia: Cilia development, morphogenesis, and function in C. elegans  

PubMed Central

In the free-living nematode Caenorhabditis elegans, cilia are found on the dendritic endings of sensory neurons. C. elegans cilia are classified as `primary' or `sensory' according to the `9+0' axonemal ultrastiucture (nine doublet outer microtubules with no central microtubule pair) and lack of motility, characteristics of `9+2' cilia. The C. elegans ciliated nervous system allows the animal to perceive environmental stimuli and make appropriate developmental, physiological, and behavioral decisions. In vertebrates, the biological significance of primary cilia had been largely neglected. Recent findings have placed primary/sensory cilia in the center of cellular signaling and developmental processes. Studies using genetic model organisms such as C. elegans identified the link between ciliary dysfunction and human ciliopathies. Future studies in the worm will address important basic questions regarding ciliary development, morphogenesis, specialization, and signaling functions. PMID:18508635

Bae, Young-Kyung; Barr, Maureen M.

2011-01-01

151

Insomnia-related complaints correlate with functional connectivity between sensory-motor regions.  

PubMed

According to the hyperarousal theory of insomnia, difficulty in initiating or maintaining sleep occurs as a result of increased cognitive and physiological arousal caused by acute stressors and associated cognitive rumination, placing the individual in a perpetual cycle of hyperarousal and increased sensitivity to sensory stimulation. We tested the hypothesis that difficulty in initiating or maintaining sleep would be associated with increased functional connectivity between primary sensory processing and motor planning regions. Fifty-eight healthy adults (29 men, 29 women) completed a self-report inventory about sleep onset and maintenance problems and underwent a 6-min resting-state functional MRI scan. Bilateral regions of interest (ROIs) were placed in primary visual cortex, auditory cortex, olfactory cortex, and the supplementary motor cortex, and the mean processed signal time course was extracted and correlated with each of the other ROIs. Difficulty in falling asleep was associated with increased functional connectivity between the primary visual cortex and other sensory regions such as the primary auditory cortex, olfactory cortex, and the supplementary motor cortex. The primary auditory cortex also showed greater connectivity with the supplementary motor cortex in those with sleep initiation problems. Problems with sleep maintenance were associated with greater connectivity between the primary visual cortex and the olfactory cortex. Consistent with the predictions of the hyperarousal model, difficulty in falling asleep was associated with greater functional connectivity between primary sensory and supplementary motor regions. Such augmented functional connectivity may contribute to the sustained sensory processing of environmental stimuli, potentially prolonging the latency to sleep. PMID:23399993

Killgore, William D S; Schwab, Zachary J; Kipman, Maia; Deldonno, Sophie R; Weber, Mareen

2013-03-27

152

Crocin Enhanced Functional Recovery after Sciatic Nerve Crush Injury in Rats  

PubMed Central

Objective(s): Crocin is a constituent of saffron and has many biological functions. The present study aimed to investigate the effects of intraperitoneal (IP) injection of crocin on sciatic nerve regeneration in male Wistar rats. Materials and Methods: Fifty-four rats were divided into 9 groups: groups 1-4 (intact + normal saline and intact + crocin at doses of 5, 20 and 80 mg/kg, respectively); group 5 (sham surgery + normal saline); groups 6-9 (crush + normal saline and crush + crocin at doses of 5, 20 and 80 mg/kg, respectively). Normal saline and crocin were IP injected for 10 consecutive days after induction of a standard crush injury in left sciatic nerve. Footprints were obtained 1 day before and weekly after induction of nerve injury for evaluation of sciatic functional index (SFI). Blood samples were taken for evaluation of malondialdehyde (MDA) levels. Histopathological changes of sciatic nerve were investigated by light microscopy. Results: Sciatic nerve crush-injured rats showed SFI values reduction, increased plasma MDA levels and produced Wallerian degeneration in sciatic nerve. Crocin at a dose of 5 mg/kg had no significant effects. At doses of 20 and 80 mg/kg, crocin accelerated the SFI recovery, decreased MDA levels and reduced Wallerian degeneration severity. Conclusion: The present study suggests that the neuroprotective effects afforded by crocin may be due in part to reduction of free radicals-induced toxic effects. PMID:23638296

Tamaddonfard, Esmaeal; Farshid, Amir Abbas; Ahmadian, Elham; Hamidhoseyni, Abbas

2013-01-01

153

The effect of memantine on functional recovery of the facial nerve after crush injury.  

PubMed

The objective of this study is to establish whether memantine is an alternative and effective treatment on facial nerve recovery after crush injury, and also to analyze the effective doses of this promising agent. This is a randomized controlled animal study. 40 rats underwent crush injury to left main trunk of the facial nerve, and divided into 4 groups; (1) control (saline treated), (2) 5-mg/kg memantine, (3) 10-mg/kg memantine, and (4) 20-mg/kg memantine group. Facial nerve functions were evaluated by eye reflex, and whisker movement compared to the unaffected side. They were scored on a 3-point scale. On day 28, the rats were sacrificed, and the facial nerves were dissected. The paraffin sections were studied with caspase-3 immunostaining. According to statistical data, the recovery in Group 4 began significantly earlier than the other groups on the basis of restoring eye blink reflexes and whisker movement. Groups 2 and 3 showed faster recovery than Group 1 on the basis of whisker movement. The caspase-3 positive staining was rarely detected in all groups. The Kruskal-Wallis test revealed that Group 4 showed fewer apoptotic cells than other groups; this was statistically significant. However, the Mann-Whitney U test with the Bonferroni correction did not reveal any significant difference between the groups. In conclusion, this study revealed that memantine acted to restore facial nerve functions, and accelerate recovery after facial nerve injury by inhibiting apoptosis. PMID:24659363

Topdag, Murat; Topdag, Deniz Ozlem; Ila, Kadri; Muezzinoglu, Bahar; Yaprak, Busra; Ozturk, Murat; Caliskan, Sebla; Iseri, Mete

2014-03-23

154

Magnetic stimulation of mammalian peripheral nerves in vivo: An alternative to functional electrical stimulation.  

PubMed

Functional electrical stimulation is the current gold standard for stimulating neuronal interfaces for functional neuromuscular and cortical applications, but it is not without its drawbacks. One such fault is the need to have direct electrical contact with the nerve tissue, and any side effects this causes. Functional magnetic stimulation, which works though electromagnetic induction, does not require electrical contact and may be a viable alternative to functional electrical stimulation. We are investigating the capabilities of magnetic stimulation with centimeter scale (<; 2.5 cm) coils in feline and rodent sciatic nerves in vivo. We have shown that magnetic stimulation can consistently produce the same levels of neuromuscular activation as electrical stimulation. Additionally, the position of the coil relative to the nerve influences neuromuscular activation, suggesting the possibility of selective muscle activation. PMID:25570516

Kagan, Zachary B; RamRakhyani, Anil Kumar; Khan, Faisal; Lazzi, Gianluca; Normann, Richard A; Warren, David J

2014-08-01

155

Directed nerve regeneration enabled by wirelessly powered electrodes printed on a biodegradable polymer.  

PubMed

Wirelessly directed nerve regeneration: inductively powered electrical stimulation circuits on the biodegradable polymer polycaprolactone demonstrate directed regeneration of sensory neurons from a dorsal root ganglion. These circuits, produced using a unique transfer printing process, illustrate progress towards the use of electrical stimulation systems on biodegradable materials to improve peripheral nerve repair functional outcomes. PMID:24376117

Martin, Christopher; Dejardin, Théophile; Hart, Andrew; Riehle, Mathis O; Cumming, David R S

2014-07-01

156

Ageing alters perivascular nerve function of mouse mesenteric arteries in vivo  

PubMed Central

Mesenteric arteries (MAs) are studied widely in vitro but little is known of their reactivity in vivo. Transgenic animals have enabled Ca2+ signalling to be studied in isolated MAs but the reactivity of these vessels in vivo is undefined. We tested the hypothesis that ageing alters MA reactivity to perivascular nerve stimulation (PNS) and adrenoreceptor (AR) activation during blood flow control. First- (1A), second- (2A) and third-order (3A) MAs of pentobarbital-anaesthetized Young (3–6 months) and Old (24–26 months) male and female Cx40BAC-GCaMP2 transgenic mice (C57BL/6 background; positive or negative for the GCaMP2 transgene) were studied with intravital microscopy. A segment of jejunum was exteriorized and an MA network was superfused with physiological salt solution (pH 7.4, 37°C). Resting tone was ? 10% in MAs of Young and Old mice; diameters were ?5% (1A), 20% (2A) and 40% (3A) smaller (P? 0.05) in Old mice. Throughout MA networks, vasoconstriction increased with PNS frequency (1–16 Hz) but was ?20% less in Young vs. Old mice (P? 0.05) and was inhibited by tetrodotoxin (1 ?m). Capsaicin (10 ?m; to inhibit sensory nerves) enhanced MA constriction to PNS (P? 0.05) by ?20% in Young but not Old mice. Phenylephrine (an ?1AR agonist) potency was greater in Young mice (P? 0.05) with similar efficacy (?60% constriction) across ages and MA branches. Constrictions to UK14304 (an ?2AR agonist) were less (?20%; P? 0.05) and were unaffected by ageing. Irrespective of sex or transgene expression, ageing consistently reduced the sensitivity of MAs to ?1AR vasoconstriction while blunting the attenuation of sympathetic vasoconstriction by sensory nerves. These findings imply substantive alterations in splanchnic blood flow control with ageing. PMID:23247111

Westcott, Erika B; Segal, Steven S

2013-01-01

157

Importance of Tissue Morphology Relative to Patient Reports of Symptoms and Functional Limitations Resulting From Median Nerve Pathology  

PubMed Central

Significant data exist for the personal, environmental, and occupational risk factors for carpal tunnel syndrome. Few data, however, explain the interrelationship of tissue morphology to these factors among patients with clinical presentation of median nerve pathology. Therefore, our primary objective was to examine the relationship of various risk factors that may be predictive of subjective reports of symptoms or functional deficits accounting for median nerve morphology. Using diagnostic ultrasonography, we observed real-time median nerve morphology among 88 participants with varying reports of symptoms or functional limitations resulting from median nerve pathology. Body mass index, educational level, and nerve morphology were the primary predictive factors. Monitoring median nerve morphology with ultrasonography may provide valuable information for clinicians treating patients with symptoms of median nerve pathology. Sonographic measurements may be a useful clinical tool for improving treatment planning and provision, documenting patient status, or measuring clinical outcomes of prevention and rehabilitation interventions. PMID:23245784

Evans, Kevin D.; Li, Xiaobai; Sommerich, Carolyn M.; Case-Smith, Jane

2013-01-01

158

Sensoric Protection after Median Nerve Injury: Babysitter-Procedure Prevents Muscular Atrophy and Improves Neuronal Recovery  

PubMed Central

The babysitter-procedure might offer an alternative when nerve reconstruction is delayed in order to overcome muscular atrophy due to denervation. In this study we aimed to show that a sensomotoric babysitter-procedure after median nerve injury is capable of preserving irreversible muscular atrophy. The median nerve of 20 female Wistar rats was denervated. 10 animals received a sensory protection with the N. cutaneous brachii. After six weeks the median nerve was reconstructed by autologous nerve grafting from the contralateral median nerve in the babysitter and the control groups. Grasping tests measured functional recovery over 15 weeks. At the end of the observation period the weight of the flexor digitorum sublimis muscle was determined. The median nerve was excised for histological examinations. Muscle weight (P < 0.0001) was significantly superior in the babysitter group compared to the control group at the end of the study. The histological evaluation revealed a significantly higher diameter of axons (P = 0.0194), nerve fiber (P = 0.0409), and nerve surface (P = 0.0184) in the babysitter group. We conclude that sensory protection of a motor nerve is capable of preserving muscule weight and we may presume that metabolism of the sensory nerve was sufficient to keep the target muscle's weight and vitality. PMID:25133176

Beck-Broichsitter, Benedicta E.; Becker, Stephan T.; Lamia, Androniki; Fregnan, Federica; Sinis, Nektarios

2014-01-01

159

The contribution of sensory system functional connectivity reduction to clinical pain in fibromyalgia.  

PubMed

Fibromyalgia typically presents with spontaneous body pain with no apparent cause and is considered pathophysiologically to be a functional disorder of somatosensory processing. We have investigated potential associations between the degree of self-reported clinical pain and resting-state brain functional connectivity at different levels of putative somatosensory integration. Resting-state functional magnetic resonance imaging was obtained in 40 women with fibromyalgia and 36 control subjects. A combination of functional connectivity-based measurements were used to assess (1) the basic pain signal modulation system at the level of the periaqueductal gray (PAG); (2) the sensory cortex with an emphasis on the parietal operculum/secondary somatosensory cortex (SII); and (3) the connectivity of these regions with the self-referential "default mode" network. Compared with control subjects, a reduction of functional connectivity was identified across the 3 levels of neural processing, each showing a significant and complementary correlation with the degree of clinical pain. Specifically, self-reported pain in fibromyalgia patients correlated with (1) reduced connectivity between PAG and anterior insula; (2) reduced connectivity between SII and primary somatosensory, visual, and auditory cortices; and (3) increased connectivity between SII and the default mode network. The results confirm previous research demonstrating abnormal functional connectivity in fibromyalgia and show that alterations at different levels of sensory processing may contribute to account for clinical pain. Importantly, reduced functional connectivity extended beyond the somatosensory domain and implicated visual and auditory sensory modalities. Overall, this study suggests that a general weakening of sensory integration underlies clinical pain in fibromyalgia. PMID:24792477

Pujol, Jesus; Macià, Dídac; Garcia-Fontanals, Alba; Blanco-Hinojo, Laura; López-Solà, Marina; Garcia-Blanco, Susana; Poca-Dias, Violant; Harrison, Ben J; Contreras-Rodríguez, Oren; Monfort, Jordi; Garcia-Fructuoso, Ferran; Deus, Joan

2014-08-01

160

Structural and functional association between substance P- and calcitonin gene-related peptide-immunoreactive nerves and accessory cells in the rat dental pulp.  

PubMed

Defense mechanisms of the dentin/pulp complex involve a variety of biological systems in which immunocompetent cells, the nervous system, and the vascular supply play important roles. In the present study, pulpal accessory cells were examined regarding (i) their structural relationship to nerves and (ii) how the functional capacities of these cells were affected by neuropeptides. Micro-anatomic association was investigated in the normal rat molar pulp with the use of double-immunofluorescence staining and dual-channel confocal laser scanning microscopy. Examinations of confocal laser scanning microscopic images from single focal planes revealed the presence of apparent contacts between thin, varicose nerve fibers and immunocompetent cells, indicating proximity between these two structures. The close associations were most frequently observed in the para-odontoblastic region of the coronal pulp, where more than 70% of class II antigen-expressing (OX6+) cells showed proximity to nerve fibers immunoreactive to calcitonin gene-related peptide. The corresponding figure for substance P was about 50%. ED2+ macrophages closely associated with nerves were less frequently observed. Functional studies conducted in vitro demonstrated that 10(-9) to 10(-7) mol/L of substance P significantly increased (p < 0.05), while 10(-7) to 10(-6) mol/L of calcitonin gene-related peptide suppressed (p < 0.01) proliferation of purified T-lymphocytes stimulated with sub-optimal concentrations of concanavalin A in the presence of rat incisor pulpal cells as accessory cells. These data suggest that pulpal sensory nerve fibers and their products may have an influence upon the immune defense of the dental pulp. PMID:9390474

Okiji, T; Jontell, M; Belichenko, P; Dahlgren, U; Bergenholtz, G; Dahlström, A

1997-12-01

161

Roles of mast cells and sensory nerves in cutaneous vascular hyperpermeability and scratching behavior induced by poly-L-arginine in rats.  

PubMed

We investigated whether the polycation poly-L-arginine elicited cutaneous vascular hyperpermeability and scratching behavior and, if so, whether these responses involved mast cells and sensory nerves in rats. Intradermal injections of poly-L-arginine induced vascular hyperpermeability and scratching behavior. Combined treatment with chlorpheniramine and methysergide almost completely suppressed the poly-L-arginine (50 microg/site)-induced plasma leakage. Capsaicin desensitization and the tachykinin NK(1) receptor antagonist LY303870, (R)-1-[N-(2-methoxybenzyl)acetylamino]-3-(1H-indol-3-yl)-2-[N-(2-(4-(piperidin-1-yl)piperidin-1-yl)acetyl)amino]propane, partially inhibited the leakage. In mast cell-deficient rats, poly-L-arginine only minimally induced plasma leakage. On the other hand, capsaicin desensitization and LY303870, but not chlorpheniramine or methysergide, suppressed the poly-L-arginine (200 microg/site)-induced scratching. Moreover, poly-L-arginine elicited the scratching even in mast cell-deficient rats. These results suggest that substance P is at least partly involved in both the cutaneous plasma leakage and the scratching behavior induced by poly-L-arginine. Moreover, mast cell-derived amines are suggested to be involved in the plasma extravasation but scarcely, if any, in the scratching behavior. PMID:11513841

Hayashi, K; Sato, H; Kaise, T; Ohmori, K; Ishii, A; Sano, J; Karasawa, A

2001-08-17

162

IgSF8: a developmentally and functionally regulated cell adhesion molecule in olfactory sensory neuron axons and synapses  

PubMed Central

Here, we investigated an Immunoglobulin (Ig) superfamily protein IgSF8 which is abundantly expressed in olfactory sensory neuron (OSN) axons and their developing synapses. We demonstrate that expression of IgSF8 within synaptic neuropil is transitory, limited to the period of glomerular formation. Glomerular expression decreases after synaptic maturation and compartmental glomerular organization is achieved, although expression is maintained at high levels within the olfactory nerve layer (ONL). Immunoprecipitations indicate that IgSF8 interacts with tetraspanin CD9 in the olfactory bulb (OB). CD9 is a component of tetraspanin-enriched microdomains (TEMs), specialized microdomains of the plasma membrane known to regulate cell morphology, motility, invasion, fusion and signaling, in both the nervous and immune systems, as well as in tumors. In vitro, both IgSF8 and CD9 localize to puncta within axons and growth cones of OSNs, consistent with TEM localization. When the olfactory epithelium (OE) was lesioned, forcing OSN regeneration en masse, IgSF8 was once again able to be detected in OSN axons terminals as synapses were reestablished. Finally, we halted synaptic maturation within glomeruli by unilaterally blocking functional activity and found that IgSF8 did not undergo exclusion from this subcellular compartment and instead continued to be detected in adult glomeruli. These data support the hypothesis that IgSF8 facilitates OSN synapse formation. PMID:22687584

Ray, Arundhati; Treloar, Helen B.

2012-01-01

163

IgSF8: a developmentally and functionally regulated cell adhesion molecule in olfactory sensory neuron axons and synapses.  

PubMed

Here, we investigated an Immunoglobulin (Ig) superfamily protein IgSF8 which is abundantly expressed in olfactory sensory neuron (OSN) axons and their developing synapses. We demonstrate that expression of IgSF8 within synaptic neuropil is transitory, limited to the period of glomerular formation. Glomerular expression decreases after synaptic maturation and compartmental glomerular organization is achieved, although expression is maintained at high levels within the olfactory nerve layer (ONL). Immunoprecipitations indicate that IgSF8 interacts with tetraspanin CD9 in the olfactory bulb (OB). CD9 is a component of tetraspanin-enriched microdomains (TEMs), specialized microdomains of the plasma membrane known to regulate cell morphology, motility, invasion, fusion and signaling, in both the nervous and immune systems, as well as in tumors. In vitro, both IgSF8 and CD9 localize to puncta within axons and growth cones of OSNs, consistent with TEM localization. When the olfactory epithelium (OE) was lesioned, forcing OSN regeneration en masse, IgSF8 was once again able to be detected in OSN axon terminals as synapses were reestablished. Finally, we halted synaptic maturation within glomeruli by unilaterally blocking functional activity and found that IgSF8 did not undergo exclusion from this subcellular compartment and instead continued to be detected in adult glomeruli. These data support the hypothesis that IgSF8 facilitates OSN synapse formation. PMID:22687584

Ray, Arundhati; Treloar, Helen B

2012-07-01

164

Piezoelectric materials mimic the function of the cochlear sensory epithelium  

PubMed Central

Cochlear hair cells convert sound vibration into electrical potential, and loss of these cells diminishes auditory function. In response to mechanical stimuli, piezoelectric materials generate electricity, suggesting that they could be used in place of hair cells to create an artificial cochlear epithelium. Here, we report that a piezoelectric membrane generated electrical potentials in response to sound stimuli that were able to induce auditory brainstem responses in deafened guinea pigs, indicating its capacity to mimic basilar membrane function. In addition, sound stimuli were transmitted through the external auditory canal to a piezoelectric membrane implanted in the cochlea, inducing it to vibrate. The application of sound to the middle ear ossicle induced voltage output from the implanted piezoelectric membrane. These findings establish the fundamental principles for the development of hearing devices using piezoelectric materials, although there are many problems to be overcome before practical application. PMID:22025702

Inaoka, Takatoshi; Shintaku, Hirofumi; Nakagawa, Takayuki; Kawano, Satoyuki; Ogita, Hideaki; Sakamoto, Tatsunori; Hamanishi, Shinji; Wada, Hiroshi; Ito, Juichi

2011-01-01

165

Immunohistochemical analysis of the adhesive papillae of Botrylloides leachi (Chordata, Tunicata, Ascidiacea): Implications for their sensory function  

Microsoft Academic Search

Most ascidian larvae settle and begin adhesion by means of three mucus secreting and sensory organs, the adhesive papillae or palps. However, the adhesive papillae of Botrylloides genus larvae, despite their name, have only a sensory function. By immunohistochemical localization of serotonin and ??tubulin, we demonstrated that the adhesive papillae of Botrylloides leachi contain two distinct types of neurons with

R. Pennati; G. Zega; S. Groppelli; F. De Bernardi

2007-01-01

166

Clinical Evaluation of the Effectiveness of Sensory Integrative and Perceptual Motor Therapy in Improving Sensory Integrative Function in Children with Learning Disabilities.  

ERIC Educational Resources Information Center

After 72 sessions for 3 hours per week, significantly more children aged 5-9 receiving sensory integration (SI) therapy (n=35) and perceptual motor training (n=35) showed improvement in SI functioning compared to 33 receiving no treatment. Similar effects were found for subgroups with vestibular dysfunction only (n=11, 13, and 11 respectively).…

Humphries, Thomas W.; And Others

1993-01-01

167

Functional diversity among sensory receptors in a Drosophila olfactory circuit  

PubMed Central

The ability of an animal to detect, discriminate, and respond to odors depends on the function of its olfactory receptor neurons (ORNs), which in turn depends ultimately on odorant receptors. To understand the diverse mechanisms used by an animal in olfactory coding and computation, it is essential to understand the functional diversity of its odor receptors. The larval olfactory system of Drosophila melanogaster contains 21 ORNs and a comparable number of odorant receptors whose properties have been examined in only a limited way. We systematically screened them with a panel of ?500 odorants, yielding >10,000 receptor–odorant combinations. We identify for each of 19 receptors an odorant that excites it strongly. The responses elicited by each of these odorants are analyzed in detail. The odorants elicited little cross-activation of other receptors at the test concentration; thus, low concentrations of many of these odorants in nature may be signaled by a single ORN. The receptors differed dramatically in sensitivity to their cognate odorants. The responses showed diverse temporal dynamics, with some odorants eliciting supersustained responses. An intriguing question in the field concerns the roles of different ORNs and receptors in driving behavior. We found that the cognate odorants elicited behavioral responses that varied across a broad range. Some odorants elicited strong physiological responses but weak behavioral responses or weak physiological responses but strong behavioral responses. PMID:23690583

Mathew, Dennis; Martelli, Carlotta; Kelley-Swift, Elizabeth; Brusalis, Christopher; Gershow, Marc; Samuel, Aravinthan D. T.; Emonet, Thierry; Carlson, John R.

2013-01-01

168

Functional diversity among sensory receptors in a Drosophila olfactory circuit.  

PubMed

The ability of an animal to detect, discriminate, and respond to odors depends on the function of its olfactory receptor neurons (ORNs), which in turn depends ultimately on odorant receptors. To understand the diverse mechanisms used by an animal in olfactory coding and computation, it is essential to understand the functional diversity of its odor receptors. The larval olfactory system of Drosophila melanogaster contains 21 ORNs and a comparable number of odorant receptors whose properties have been examined in only a limited way. We systematically screened them with a panel of ?500 odorants, yielding >10,000 receptor-odorant combinations. We identify for each of 19 receptors an odorant that excites it strongly. The responses elicited by each of these odorants are analyzed in detail. The odorants elicited little cross-activation of other receptors at the test concentration; thus, low concentrations of many of these odorants in nature may be signaled by a single ORN. The receptors differed dramatically in sensitivity to their cognate odorants. The responses showed diverse temporal dynamics, with some odorants eliciting supersustained responses. An intriguing question in the field concerns the roles of different ORNs and receptors in driving behavior. We found that the cognate odorants elicited behavioral responses that varied across a broad range. Some odorants elicited strong physiological responses but weak behavioral responses or weak physiological responses but strong behavioral responses. PMID:23690583

Mathew, Dennis; Martelli, Carlotta; Kelley-Swift, Elizabeth; Brusalis, Christopher; Gershow, Marc; Samuel, Aravinthan D T; Emonet, Thierry; Carlson, John R

2013-06-01

169

Functional recovery of odor representations in regenerated sensory inputs to the olfactory bulb  

PubMed Central

The olfactory system has a unique capacity for recovery from peripheral damage. After injury to the olfactory epithelium (OE), olfactory sensory neurons (OSNs) regenerate and re-converge on target glomeruli of the olfactory bulb (OB). Thus far, this process has been described anatomically for only a few defined populations of OSNs. Here we characterize this regeneration at a functional level by assessing how odor representations carried by OSN inputs to the OB recover after massive loss and regeneration of the sensory neuron population. We used chronic imaging of mice expressing synaptopHluorin in OSNs to monitor odor representations in the dorsal OB before lesion by the olfactotoxin methyl bromide and after a 12 week recovery period. Methyl bromide eliminated functional inputs to the OB, and these inputs recovered to near-normal levels of response magnitude within 12 weeks. We also found that the functional topography of odor representations recovered after lesion, with odorants evoking OSN input to glomerular foci within the same functional domains as before lesion. At a finer spatial scale, however, we found evidence for mistargeting of regenerated OSN axons onto OB targets, with odorants evoking synaptopHluorin signals in small foci that did not conform to a typical glomerular structure but whose distribution was nonetheless odorant-specific. These results indicate that OSNs have a robust ability to reestablish functional inputs to the OB and that the mechanisms underlying the topography of bulbar reinnervation during development persist in the adult and allow primary sensory representations to be largely restored after massive sensory neuron loss. PMID:24431990

Cheung, Man C.; Jang, Woochan; Schwob, James E.; Wachowiak, Matt

2014-01-01

170

Functional recovery guided by an electrospun silk fibroin conduit after sciatic nerve injury in rats.  

PubMed

The aim of this study was to evaluate the regenerative capacity of a newly developed nerve guidance conduit using electrospun silk fibroin (SFNC) implanted in a 10-mm defect of the sciatic nerve in rats. After evaluating the physical properties and cytocompatibility of SFNC in vitro, rats were randomly allocated into three groups: defect only, autograft and SFNC. To compare motor function and abnormal sensation among groups, ankle stance angle (ASA) and severity of autotomy were observed for 10?weeks after injury. Immunostaining with axonal neurofilament (NF) and myelin basic protein (MBP) antibodies were performed to investigate regenerated nerve fibres inside SFNC. ASA increased significantly in the SFNC group at 1, 7 and 10?weeks after injury compared to the defect only group (p?nerve fibres stained with NF and MBP were found inside SFNC. In conclusion, SFNC could be helpful in restoring motor function and preventing abnormal sensations after nerve injury. Copyright © 2012 John Wiley & Sons, Ltd. PMID:23086833

Park, Sook Young; Ki, Chang Seok; Park, Young Hwan; Lee, Kwang Gill; Kang, Seok Woo; Kweon, Hae Yong; Kim, Hyun Jeong

2015-01-01

171

Raman microspectroscopy for visualization of peripheral nerves  

NASA Astrophysics Data System (ADS)

The peripheral nervous system plays an important role in motility, sensory, and autonomic functions of the human body. Preservation of peripheral nerves in surgery is essential for improving quality of life of patients. To preserve peripheral nerves, detection of ne peripheral nerves that cannot be identi ed by human eye or under white light imaging is necessary. In this study, we sought to provide a proof-of-principle demonstration of a label-free detection technique of peripheral nerve tissues against adjacent tissues that employs spontaneous Raman microspectroscopy. A line-illumination confocal Raman microscope was used for the experiment. A laser operating at the wavelength of 532 nm was used as an excitation laser light. We obtained Raman spectra of peripheral nerve, brous connective tissue, skeletal muscle, blood vessel, and adipose tissue of Wistar rats, and extracted speci c spectral features of peripheral nerves and adjacent tissues. By applying multivariate image analysis, peripheral nerves were clearly detected against adjacent tissues without any preprocessing neither xation nor staining. These results suggest the potential of the Raman spectroscopic observation for noninvasive and label-free nerve detection, and we expect this method could be a key technique for nerve-sparing surgery.

Minamikawa, Takeo; Harada, Yoshinori; Koizumi, Noriaki; Takamatsu, Tetsuro

2013-02-01

172

Effects of safranal, a constituent of saffron, and vitamin E on nerve functions and histopathology following crush injury of sciatic nerve in rats.  

PubMed

Safranal is one of the major components of saffron and has many biological effects such as antioxidant property. The present study investigated the effects of safranal on sciatic nerve function after induction of crush injury. We also used of vitamin E as a reference potent antioxidant agent. In anesthetized rats, right sciatic nerve was crushed using a small haemostatic forceps. Functional recovery was assessed using sciatic functional index (SFI). Acetone spray and von Frey filament tests were used for neuropathic pain assay. Histopathological changes including severities of Wallerian degeneration of sciatic nerve and gastrocnemius muscle atrophy were investigated by light microscopy. Blood levels of malodialdehyde (MDA) were also measured. The SFI values were accelerated, cold and mechanical allodynia were suppressed, the severities of Wallerian degeneration and muscular atrophy were improved, and the increased MDA level was reversed with 10 consecutive days intraperitoneal injections of 0.2 and 0.8 mg/kg of safranal and 100 mg/kg of vitamin E. It is concluded that safranal and vitamin E produced same improving effects on crushed-injured sciatic nerve functions. Inhibition of oxidative stress pathway may be involved in improving effects of safranal and vitamin E on functions and histopathology of an injured peripheral nerve. PMID:24315349

Tamaddonfard, Esmaeal; Farshid, Amir Abbas; Maroufi, Shirin; Kazemi-Shojaei, Sharare; Erfanparast, Amir; Asri-Rezaei, Siamak; Taati, Mina; Dabbaghi, Milad; Escort, Mona

2014-04-15

173

Effect of Structure on Function in Model Nerve Nets  

PubMed Central

A theoretical analysis has been made on the effect of the pattern of interneuronal connectivity in model nerve nets on the activity of these nets. Two types of nets have been investigated: one in which the likelihood of a connection between a given neuron and any other element in the net is given by a Poisson probability distribution, and a second type in which the pattern of interconnection follows a Gaussian distribution. An analytical treatment is presented of the equations for noiseless nets in these two conditions. The principal result is that nets with Poisson connectivity law are activated by extraneous firing of a single neuron and continue in spontaneous activity indefinitely. On the other hand, similar nets in which the connections are, however, distributed according to a normal connectivity law, exhibit a definite threshold and produce spontaneous activity only subsequent to extraneous activation of a substantial fraction of the population. Moreover, spontaneous activity in Gaussian nets, but not in Poisson nets, becomes extinguished if the number of active neurons falls below the critical threshold. Some neuroanatomical implications are discussed which suggest that the pyramidal system of the cerebral cortex and other neuronal systems histologically characterized by large numbers of synapses per neuron may incorporate a Gaussian connectivity law, whereas a Poisson law may be characteristic of these cortical layers and nuclei primarily containing granule cells. PMID:4811818

Anninos, Photios A.; Elul, Rafael

1974-01-01

174

Computer Simulation of Nerve Transfer Strategies for Restoring Shoulder Function after Adult C5-C6 Root Avulsion Injuries  

PubMed Central

Background Functional ability following nerve transfer for upper brachial plexus injuries relies on both the function and magnitude of force recovery of targeted muscles. Following nerve transfers targeting either the axillary nerve, suprascapular nerve, or both, it is unclear whether functional ability is restored in face of limited muscle force recovery. Methods We used a computer model to simulate flexing the elbow while maintaining a functional shoulder posture for 3 nerve transfer scenarios. The minimum restored force capacity necessary to perform the task, associated compensations by neighboring muscles, and the effect of altered muscle coordination on movement effort, were assessed. Results The minimum force restored by the axillary, suprascapular, and combined nerve transfers that was required for the model to simulate the desired movement was 25%, 40%, and 15% of the unimpaired muscle force capacity, respectively. When the deltoid was paralyzed, the infraspinatus and subscapularis muscles generated higher shoulder abduction moments to compensate for deltoid weakness. For all scenarios, movement effort increased as restored force capacity decreased. Conclusions Combined axillary and suprascapular nerve transfer required the least restored force capacity to perform the desired elbow flexion task, while single suprascapular nerve transfer required the most restored force capacity to perform the same task. Though compensation mechanisms allowed all scenarios to perform the desired movement despite weakened shoulder muscles, compensation increased movement effort. Dynamic simulations allowed independent evaluation of the effect of restored force capacity on functional outcome in a way that is not possible experimentally. Clinical Relevance Simultaneous nerve transfer to suprascapular and axillary nerves yields the best simulated biomechanical outcome for lower magnitudes of muscle force recovery in this computer model. Axillary nerve transfer performs nearly as well as the combined transfer, while suprascapular nerve transfer is more sensitive to the magnitude of reinnervation and therefore avoided. PMID:21903345

Crouch, Dustin L.; Li, Zhongyu; Barnwell, Jonathan C.; Plate, Johannes F.; Daly, Melissa; Saul, Katherine R.

2011-01-01

175

Experimental approaches to promote functional recovery after severe peripheral nerve injuries  

Microsoft Academic Search

Summary  INTRODUCTION: Reduced regenerative capacity of chronically axotomized neurons and reduced growth support by atrophic Schwann cells are key factors that account for the poor functional outcomes after proximal nerve injuries. In this study we examine two strategies aimed to circumvent deleterious effects of chronic axotomy and chronic denervation on axonal regeneration: (1) exogenous application of neurotrophic factors to chronically axotomized

T. Gordon; J. G. Boyd; O. A. R. Sulaiman

2005-01-01

176

Predicting recovery of facial nerve function following injury from a basilar skull fracture.  

PubMed

Twenty-five patients with posttraumatic facial nerve palsy were studied. Partial recovery of function had occurred in 95% of these patients by 18 months after injury. At 5 months posttrauma, there was some recovery in 92.5% of those with a partial lesion compared with 10% of those with a complete lesion. This difference attains statistical significance. Complete recovery of nerve function had occurred by 10.5 months in 53.5% of the patients; in 62% of patients with a partial lesion, complete recovery had occurred by 4 months compared with 0% in those with a complete lesion. This difference also attains statistical significance. There was no statistically significant difference in recovery of function between patients with an immediate as opposed to a delayed onset of facial nerve palsy. It was determined that the degree of palsy had a statistically significant influence on recovery of facial nerve function, whereas the time of onset did not. The data presented support a conservative approach to these injuries and it is recommended that the possibility of surgical treatment should be entertained in patients with complete facial palsy persisting for 12 to 18 months after injury. PMID:1919699

Adegbite, A B; Khan, M I; Tan, L

1991-11-01

177

Identification of Nerves in Ultrasound Scans Using a Modified Mumford-Shah Functional  

E-print Network

in medical imaging is ultrasound, since it does not use ionizing radiation which imposes potential hazardsIdentification of Nerves in Ultrasound Scans Using a Modified Mumford-Shah Functional and Prior Information Jung-Ha An, Paul Bigeleisen, and Steven Damelin Abstract--Ultrasound scans have many important

Damelin, Steven

178

Functional regeneration of severed peripheral nerve using an implantable electrical stimulator  

Microsoft Academic Search

This paper presents functional regeneration of severed peripheral nerve using a polymer-based implantable electrical stimulator. A polyimide based conduit electrode was made by micro-fabrication and a stimulation chip was designed to generate biphasic current pulse for electrical stimulation. The stimulation chip was packaged with a battery using silicone elastomer, and integrated with the electrode. The implantable electrical stimulator was implanted

Tae Hyung Lee; Hui Pan; In Sook Kim; Soon Jung Hwang; S. J. Kim

2010-01-01

179

Serial Vagus Nerve Stimulation Functional MRI in Treatment-Resistant Depression  

Microsoft Academic Search

Vagus nerve stimulation (VNS) therapy has shown antidepressant effects in open acute and long-term studies of treatment-resistant major depression. Mechanisms of action are not fully understood, although clinical data suggest slower onset therapeutic benefit than conventional psychotropic interventions. We set out to map brain systems activated by VNS and to identify serial brain functional correlates of antidepressant treatment and symptomatic

Ziad Nahas; Charlotte Teneback; Jeong-Ho Chae; Qiwen Mu; Chris Molnar; Frank A Kozel; John Walker; Berry Anderson; Jejo Koola; Samet Kose; Mikhail Lomarev; Daryl E Bohning; Mark S George

2007-01-01

180

The Anticonvulsant Ethosuximide Disrupts Sensory Function to Extend C. elegans Lifespan  

PubMed Central

Ethosuximide is a medication used to treat seizure disorders in humans, and we previously demonstrated that ethosuximide can delay age-related changes and extend the lifespan of the nematode Caenorhabditis elegans. The mechanism of action of ethosuximide in lifespan extension is unknown, and elucidating how ethosuximide functions is important for defining endogenous processes that influence lifespan and for exploring the potential of ethosuximide as a therapeutic for age-related diseases. To identify genes that mediate the activity of ethosuximide, we conducted a genetic screen and identified mutations in two genes, che-3 and osm-3, that cause resistance to ethosuximide-mediated toxicity. Mutations in che-3 and osm-3 cause defects in overlapping sets of chemosensory neurons, resulting in defective chemosensation and an extended lifespan. These findings suggest that ethosuximide extends lifespan by inhibiting the function of specific chemosensory neurons. This model is supported by the observation that ethosuximide-treated animals displayed numerous phenotypic similarities with mutants that have chemosensory defects, indicating that ethosuximide inhibits chemosensory function. Furthermore, ethosuximide extends lifespan by inhibiting chemosensation, since the long-lived osm-3 mutants were resistant to the lifespan extension caused by ethosuximide. These studies demonstrate a novel mechanism of action for a lifespan-extending drug and indicate that sensory perception has a critical role in controlling lifespan. Sensory perception also influences the lifespan of Drosophila, suggesting that sensory perception has an evolutionarily conserved role in lifespan control. These studies highlight the potential of ethosuximide and related drugs that modulate sensory perception to extend lifespan in diverse animals. PMID:18949032

Collins, James J.; Evason, Kimberley; Pickett, Christopher L.; Schneider, Daniel L.; Kornfeld, Kerry

2008-01-01

181

Adult Peripheral Nerve Disorders—Nerve Entrapment, Repair, Transfer and Brachial Plexus Disorders  

PubMed Central

Learning Objectives After reviewing this article the reader should be able to: 1. Describe the pathophysiologic bases for nerve injury and how it applies to patient evaluation and management. 2. Realize the wide variety of injury patterns and associated patient complaint and physical findings associated with peripheral nerve pathology. 3. Evaluate and recommend further tests to aid in defining the diagnosis. 4. Specify treatment options and potential risks and benefits. Summary Peripheral nerve disorders comprise a gamut of problems ranging from entrapment neuropathy, to direct open traumatic injury and closed brachial plexus injury. The pathophysiology of injury defines the patient symptoms, exam findings and treatment options and is critical to accurate diagnosis and treatment. Goals of treatment include management of often associated pain and improvement of sensory and motor function. Understanding peripheral nerve anatomy is critical to adopting novel nerve transfer procedures, which may provide superior options for a variety of injury patterns. PMID:21532404

Fox, Ida K.; Mackinnon, Susan E.

2011-01-01

182

Activity-dependent silencing reveals functionally distinct itch-generating sensory neurons  

PubMed Central

The peripheral terminals of primary sensory neurons detect histamine and non-histamine itch-provoking ligands through molecularly distinct transduction mechanisms. It remains unclear, however, whether these distinct pruritogens activate the same or different afferent fibers. We utilized a strategy of reversibly silencing specific subsets of murine pruritogen-sensitive sensory axons by targeted delivery of a charged sodium-channel blocker and found that functional blockade of histamine itch did not affect the itch evoked by chloroquine or SLIGRL-NH2, and vice versa. Notably, blocking itch-generating fibers did not reduce pain-associated behavior. However, silencing TRPV1+ or TRPA1+ neurons allowed AITC or capsaicin respectively to evoke itch, implying that certain peripheral afferents may normally indirectly inhibit algogens from eliciting itch. These findings support the presence of functionally distinct sets of itch-generating neurons and suggest that targeted silencing of activated sensory fibers may represent a clinically useful anti-pruritic therapeutic approach for histaminergic and non-histaminergic pruritus. PMID:23685721

Roberson, David P.; Gudes, Sagi; Sprague, Jared M.; Patoski, Haley A. W.; Robson, Victoria K.; Blasl, Felix; Duan, Bo; Oh, Seog Bae; Bean, Bruce P.; Ma, Qiufu

2013-01-01

183

Transplantation of Embryonic Stem Cells Improves Nerve Repair and Functional Recovery After Severe Sciatic Nerve Axotomy in Rats  

Microsoft Academic Search

Extensive research has focused on transplantation of pluripo- tent stem cells for the treatment of central nervous system disorders, the therapeutic potential of stem cell therapy for injured peripheral nerves is largely unknown. We used a rat sciatic nerve transection model to test the ability of implanted embryonic stem (ES) cell-derived neural progenitor cells (ES- NPCs) in promoting repair of

Lin Cui; Jun Jiang; Ling Wei; Xin Zhou; Jamie L. Fraser; B. Joy Snider; Shan Ping Yu

2008-01-01

184

Effect of combined nicotine and shrapnel exposure on pain measures and gait after nerve injury.  

PubMed

A significant fraction of military soldiers sustain nerve injury and use tobacco or nicotine containing products. Healing of nerve injuries is influenced by many factors, such as degree of original injury, healing potential of the nerve, and general health of patient. However, recently, it has been demonstrated that the presence of retained insoluble metal fragments decreases healing. The effects of systemic nicotine administration, with or without metal fragments at the site of nerve injury, were evaluated. Both the nicotine-administered groups (nicotine, nicotine + shrapnel) showed significant increase in the peroneal function compared with untreated controls, as assessed by paw area (p < 0.05). Furthermore, to test possible role of altered sensory function, we used the hot plate assay. Latency to withdraw paw from a hot plate was significantly shorter in nicotine groups (p < 0.05). These data indicate that nicotine improves sensory and motor aspects of nerve function, in the presence or absence of shrapnel. PMID:22165666

Rittenhouse, Bradley; Hill-Pryor, Crystal D; McConathy, Adam; Parker, Peter; Franco, Nelson; Toussaint, Esra; Barker, Darrell; Prasad, Balakrishna; Pizarro, Jose M

2011-11-01

185

Bradykinin Controls Pool Size of Sensory Neurons Expressing Functional ?-Opioid Receptors  

PubMed Central

Analgesics targeting the ?-opioid receptor (DOR) may lead to fewer side effects than conventional opioid drugs, which mainly act on ?-opioid receptors (MOR), because of the less abundant expression of DOR in the CNS compared with MOR. Analgesic potential of DOR agonists increases after inflammation, an effect that may be mediated by DOR expressed in the peripheral sensory fibers. However, the expression of functional DOR at the plasma membrane of sensory neurons is controversial. Here we have used patch-clamp recordings and total internal reflection fluorescence microscopy to study the functional expression of DOR in sensory neurons from rat trigeminal (TG) and dorsal root ganglia (DRG). Real-time total internal reflection fluorescence microscopy revealed that treatment of TG and DRG cultures with the inflammatory mediator bradykinin (BK) caused robust trafficking of heterologously expressed GFP-tagged DOR to the plasma membrane. By contrast, treatment of neurons with the DOR agonist [d-Ala2, d-Leu5]-enkephalin (DADLE) caused a decrease in the membrane abundance of DOR, suggesting internalization of the receptor after agonist binding. Patch-clamp experiments revealed that DADLE inhibited voltage-gated Ca2+ channels (VGCCs) in 23% of small-diameter TG neurons. Pretreatment with BK resulted in more than twice as many DADLE responsive neurons (54%) but did not affect the efficacy of VGCC inhibition by DADLE. Our data suggest that inflammatory mediator-induced membrane insertion of DOR into the plasma membrane of peripheral sensory neurons may underlie increased DOR analgesia in inflamed tissue. Furthermore, the majority of BK-responsive TG neurons may have a potential to become responsive to DOR ligands in inflammatory conditions. PMID:23804098

Pettinger, Louisa; Gigout, Sylvain; Linley, John E.

2013-01-01

186

PROCESSES OF EXCITATION IN THE DENDRITES AND IN THE SOMA OF SINGLE ISOLATED SENSORY NERVE CELLS OF THE LOBSTER AND CRAYFISH  

PubMed Central

The stretch receptor organs of Alexandrowicz in lobster and crayfish possess sensory neurons which have their cell bodies in the periphery. The cell bodies send dendrites into a fine nearby muscle strand and at the opposite pole they give rise to an axon running to the central nervous system. Mechanisms of excitation between dendrites, cell soma, and axon have been studied in completely isolated receptor structures with the cell components under visual observation. Two sensory neuron types were investigated, those which adapt rapidly to stretch, the fast cells, and those which adapt slowly, the slow cells. 1. Potentials recorded from the cell body of the neurons with intracellular leads gave resting potentials of 70 to 80 mv. and action potentials which in fresh preparations exceeded the resting potentials by about 10 to 20 mv. In some experiments chymotrypsin or trypsin was used to make cell impalement easier. They did not appreciably alter resting or action potentials. 2. It has been shown that normally excitation starts in the distal portion of dendrites which are depolarized by stretch deformation. The changed potential within the dendritic terminals can persist for the duration of stretch and is called the generator potential. Secondarily, by electrotonic spread, the generator potential reduces the resting potential of the nearby cell soma. This excitation spread between dendrites and soma is seen best during subthreshold excitation by relatively small stretches of normal cells. It is also seen during the whole range of receptor stretch in neurons in which nerve conduction has been blocked by an anesthetic. The electrotonic changes in the cells are graded, reflecting the magnitude and rate of rise of stretch, and presumably the changing levels of the generator potential. Thus in the present neurons the resting potential and the excitability level of the cell soma can be set and controlled over a wide range by local events within the dendrites. 3. Whenever stretch reduces the resting membrane potential, measured in the relaxed state in the cell body, by 8 to 12 mv. in slow cells and by 17 to 22 mv. in fast cells, conducted impulses are initiated. It is thought that in slow cells conducted impulses are initiated in the dendrites while in fast cells they arise in the cell body or near to it. In fresh preparations the speed of stretch does not appreciably influence the membrane threshold for discharges, while during developing fatigue the firing level is higher when extension is gradual. 4. Some of the specific neuron characteristics are: Fast receptor cells have a relatively high threshold to stretch. During prolonged stretch the depolarization of the cell soma is not well maintained, presumably due to a decline in the generator potential, resulting in cessation of discharges in less than a minute. This appears to be the basis of the relatively rapid adaptation. A residual subthreshold depolarization can persist for many minutes of stretch. Slow cells which resemble the sensory fibers of vertebrate spindles are excited by weak stretch. Their discharge rate remains remarkably constant for long periods. It is concluded that, once threshold excitation is reached, the generator potential within slow cell dendrites is well maintained for the duration of stretch. Possible reasons for differences in discharge properties between fast and slow cells are discussed. 5. If stretch of receptor cells is gradually continued above threshold, the discharge frequency first increases over a considerable range without an appreciable change in the firing level for discharges. Beyond that range the membrane threshold for conducted responses of the cell soma rises, the impulses become smaller, and partial conduction in the soma-axon boundary region occurs. At a critical depolarization level which may be maintained for many minutes, all conduction ceases. These overstretch phenomena are reversible and resemble cathodal block. 6. The following general scheme of excitation is proposed: stretch deformation of dendritic terminals ? generat

Eyzaguirre, Carlos; Kuffler, Stephen W.

1955-01-01

187

The mechanism of sensory transduction in a mechanoreceptor. Functional stages in campaniform sensilla during the molting cycle  

PubMed Central

This paper describes the ultrastructural modifications that cockroach campaniform sensilla undergo at three major stages in the molting cycle and finds that the sensilla are physiological functional at all developmental stages leading to ecdysis. Late stage animals on the verge of ecdysis have two completely separate cuticles. The campaniform sensillum sends a 220-mum extension of the sensory process through a hole in its cap in the new (inner) cuticle across a fluid-filled molting space to its functional insertion in the cap in the old (outer) cuticle. Mechanical stimulation of the old cap excites the sensillum. The ultrastructural geometry of late stage sensilla, coupled with the observation they are physiolgically functional, supports the hypotheses (a) that sensory transduction occurs at the tip of the sensory process, and (b) that cap identation causes the cap cuticle to pinch the tip of the sensory process, thereby stimulating the sensillum. PMID:993271

1976-01-01

188

Esophagoprotective activity of angiotensin-(1-7) in experimental model of acute reflux esophagitis. Evidence for the role of nitric oxide, sensory nerves, hypoxia-inducible factor-1alpha and proinflammatory cytokines.  

PubMed

Gastroesophageal reflux disease (GERD) is a global disease rapidly increasing among world population. The pathogenesis of reflux esophagitis which is considered as the early stage of GERD is complex, resulting from an imbalance between aggressive factors damaging the esophagus and a number of the natural defense mechanisms. The esophageal mucosa is in a state of continuous exposure to potentially damaging endogenous and exogenous factors. Important aggressive components of gastric refluxate include acid and pepsin and also pancreatic enzymes and bile. Among aggressive factors of exogenous origin, cigarette smoking, non-steroidal anti-inflammatory drugs (NSAID), and steroids are of the utmost importance. The basic level of esophageal defense against acid-pepsin damage consists of the anti-reflux mechanisms such as the luminal acid clearance and removal of the esophageal contents and neutralization of luminal acidity. In addition the esophageal mucosal protection includes the presence of pre-epithelial, epithelial and post-epithelial cellular and functional components. Recently, the progress have been made in the understanding of role of the heptapeptide member of the renin-angiotensin system (RAS), angiotensin-(1-7) (Ang-(1-7)) in the control of gastrointestinal functions. It has been shown that all components of local RAS including Ang-(1-7) are detectable in the gastrointestinal wall including not only the stomach but also the esophagus. Previous studies revealed that Ang-(1-7), which is an important component of the RAS, exerts vasodilatory, anti-inflammatory and antioxidant activities in the stomach. Ang-(1-7) was recently implicated in gastroprotection, but its effects on esophageal mucosa in a rodent model of reflux esophagitis and in human subjects presenting GERD symptoms have not been explored. The present study was aimed to evaluate the possible protective effects of Ang-(1-7) and Mas-receptors upon esophageal mucosal damage in acute reflux esophagitis (RE) induced in anesthetized rats by ligating the pylorus and the limiting ridge (a transitional region between the forestomach and the corpus of stomach). Consequently, the total gastric reservoir to store gastric juice was greatly diminished, resulting in the reflux of this juice into the esophagus. Because Mas receptors are functionally linked to nitric oxide (NO) formation, we also studied involvement of endogenous NO in the mediation of protective and circulatory effects of exogenous Ang-(1-7). Moreover, an attempt was made to assess the possible role of sensory neurons in the modulation of the protective effects exerted by Ang-(1-7)/Mas receptor system. Six series of rats were pretreated 30 min before induction of RE with 1) vehicle (saline), 2) Ang-(1-7) (5-50 ?g/kg i.p.), 3) A779 (50 ?g/kg i.p.), the selective Mas receptor antagonist applied alone, 4) Ang-(1-7) (50 ?g/kg i.p.) combined with A779, 5) L-NNA (20 mg/kg i.p.) administered alone, and 6) Ang-(1-7) (50 ?g/kg i.p.) combined with L-NNA. In separate group of rats, capsaicin (total dosage of 125 mg/kg within three days) was administered s.c. 2 weeks before the induction of RE to induce functional ablation of sensory nerves. Rats with intact sensory nerves and those with capsaicin-induced sensory denervation received vehicle (saline) or Ang-(1-7) (50 ?g/kg i.p.) to determine whether this vasoactive metabolite of angiotensin I could be also effective in rats with capsaicin-induced impairment of the synthesis and release of sensory neuropeptides such as CGRP. Four hours after induction of RE, the mucosal damage was graded with mucosal lesion index (LI) from 0 to 6, the esophageal microcirculatory blood flow (EBF) was determined by H2-gas clearance technique and plasma level of pro-inflammatory cytokines interleukin-1b (IL-1?), and tumor necrosis factor-? (TNF-?) was determined by ELISA. The expression of proinflammatory factors including COX-2, cytokine IL-1? and hypoxia inducible factor 1alpha (Hif1?) was analyzed in the esophageal mucosal biopsies. In rats with RE, the esophageal LI was signi

Pawlik, M W; Kwiecien, S; Pajdo, R; Ptak-Belowska, A; Brzozowski, B; Krzysiek-Maczka, G; Strzalka, M; Konturek, S J; Brzozowski, T

2014-12-01

189

Return of function after spinal cord implantation of avulsed spinal nerve roots.  

PubMed

Avulsion of nerve roots from the spinal cord is widely regarded as an untreatable injury. However, a series of experiments in animals has shown that, if continuity is restored between spinal cord and ventral roots, axons from spinal motor neurons can regrow into the peripheral nerves with recovery of motor function. These observations were applied in the treatment of a man with avulsion of the 6th cervical (C6) to 1st thoracic roots due to brachial plexus injury. Two ventral roots were implanted into the spinal cord through slits in the pia mater, C6 directly and C7 via sural nerve grafts. Voluntary activity in proximal arm muscles was detected electromyographically after nine months and clinically after one year. After three years the patient had voluntary activity (with some co-contraction) in the deltoid, biceps, and triceps muscles. To determine whether the improvement was due to spontaneous recovery from C5, the C5 root was blocked pharmacologically, and the results indicated that the repaired roots were contributing substantially to motor function. Repair of spinal nerve roots deserves further exploration in management of brachial plexus injury. PMID:7475770

Carlstedt, T; Grane, P; Hallin, R G; Norén, G

1995-11-18

190

Subthreshold continuous electrical stimulation facilitates functional recovery of facial nerve after crush injury in rabbit.  

PubMed

We sought to determine whether electrical stimulation (ES) with subthreshold, continuous, low-frequency impulses is a viable clinical method for improving functional recovery after facial nerve crush injury. In 10 rabbits, bilateral crush injuries were made on the facial nerve by compression for 30 s with mosquito forceps, causing complete facial paralysis. Subthreshold continuous direct current ES with 20-Hz square-wave pulses was applied to the proximal stump on one side for 4 weeks. Vibrissae movement returned significantly earlier on the ES side, with a less variable recovery time. Electrophysiologically, the stimulated side had a significantly shorter latency, longer duration, and faster conduction velocity. Light and transmission electron microscopy revealed that the electrical stimulation also markedly decreased Wallerian degeneration. The average numbers of fluorescent, double-labeled nerve cells were significantly different between the ES and non-ES sides. This study shows that subthreshold, continuous, low-frequency ES immediately after a crush injury of the facial nerve results in earlier recovery of facial function and shorter overall recovery time. PMID:21254091

Kim, Jin; Han, Su Jin; Shin, Dong Hyun; Lee, Won-Sang; Choi, Jae Young

2011-02-01

191

Concurrent functional magnetic resonance imaging and electroencephalography assessment of sensory gating in schizophrenia  

PubMed Central

Schizophrenia is frequently accompanied by deficits in basic information processing, such as sensory gating. The sources behind deficient sensory gating in schizophrenia patients are, however, still largely unclear. The aim of the current study was to identify the brain structures involved in deficient sensory gating in schizophrenia patients. Twenty healthy male volunteers and 23 male schizophrenia patients were initially assessed in a somatosensory P50 suppression paradigm using concurrent electroencephalography (EEG)/functional magnetic resonance imaging (fMRI) methodology. The trials consisted of single stimuli or pairs of identical stimuli with either 500 ms or 1,000 ms interstimulus intervals. Not all subjects showed a P50 waveform as a result of the somatosensory stimuli: It was detected in 13 schizophrenia patients and 15 control subjects. Significant P50 suppression was found in the 500 ms trials in controls only. Region of interest analyses were performed for a priori chosen regions. Significant negative correlations between P50 ratios and the BOLD response were found bilaterally in the hippocampus, thalamus, anterior and posterior superior temporal gyrus (STG), and in the left inferior frontal gyrus pars opercularis. However, significant group differences were found in the hippocampus and the thalamus only. This is the first study in which P50 suppression was assessed in schizophrenia patients with concurrent fMRI/EEG methodology. The data support that the STG, thalamus, inferior frontal gyrus, and the hippocampus are involved in P50 suppression. However, of these structures only the hippocampus and thalamus appeared involved in the altered sensory processing found in schizophrenia. Hum Brain Mapp 35:3578–3587, 2014. © 2013 Wiley Periodicals, Inc. PMID:24375687

Bak, Nikolaj; Rostrup, Egill; Larsson, Henrik BW; Glenthøj, Birte Y; Oranje, Bob

2014-01-01

192

Corneal confocal microscopy reveals trigeminal small sensory fiber neuropathy in amyotrophic lateral sclerosis  

PubMed Central

Although subclinical involvement of sensory neurons in amyotrophic lateral sclerosis (ALS) has been previously demonstrated, corneal small fiber sensory neuropathy has not been reported to-date. We examined a group of sporadic ALS patients with corneal confocal microscopy, a recently developed imaging technique allowing in vivo observation of corneal small sensory fibers. Corneal confocal microscopy (CCM) examination revealed a reduction of corneal small fiber sensory nerve number and branching in ALS patients. Quantitative analysis demonstrated an increase in tortuosity and reduction in length and fractal dimension of ALS patients’ corneal nerve fibers compared to age-matched controls. Moreover, bulbar function disability scores were significantly related to measures of corneal nerve fibers anatomical damage. Our study demonstrates for the first time a corneal small fiber sensory neuropathy in ALS patients. This finding further suggests a link between sporadic ALS and facial-onset sensory and motor neuronopathy (FOSMN) syndrome, a rare condition characterized by early sensory symptoms (with trigeminal nerve distribution), followed by wasting and weakness of bulbar and upper limb muscles. In addition, the finding supports a model of neurodegeneration in ALS as a focally advancing process. PMID:25360111

Ferrari, Giulio; Grisan, Enrico; Scarpa, Fabio; Fazio, Raffaella; Comola, Mauro; Quattrini, Angelo; Comi, Giancarlo; Rama, Paolo; Riva, Nilo

2014-01-01

193

Microelectronic neural bridge for signal regeneration and function rebuilding over two separate nerves  

NASA Astrophysics Data System (ADS)

According to the feature of neural signals, a micro-electronic neural bridge (MENB) has been designed. It consists of two electrode arrays for neural signal detection and functional electrical stimulation (FES), and a microelectronic circuit for signal amplifying, processing, and FES driving. The core of the system is realized in 0.5-?m CMOS technology and used in animal experiments. A special experimental strategy has been designed to demonstrate the feasibility of the system. With the help of the MENB, the withdrawal reflex function of the left/right leg of one spinal toad has been rebuilt in the corresponding leg of another spinal toad. According to the coherence analysis between the source and regenerated neural signals, the controlled spinal toad's sciatic nerve signal is delayed by 0.72 ms in relation to the sciatic nerve signal of the source spinal toad and the cross-correlation function reaches a value of 0.73. This shows that the regenerated signal is correlated with the source sciatic signal significantly and the neural activities involved in reflex function have been regenerated. The experiment demonstrates that the MENB is useful in rebuilding the neural function between nerves of different bodies.

Xiaoyan, Shen; Zhigong, Wang; Xiaoying, Lü; Shushan, Xie; Zonghao, Huang

2011-06-01

194

Successful tactile based visual sensory substitution use functions independently of visual pathway integrity  

PubMed Central

Purpose: Neuronal reorganization after blindness is of critical interest because it has implications for the rational prescription of artificial vision devices. The purpose of this study was to distinguish the microstructural differences between perinatally blind (PB), acquired blind (AB), and normally sighted controls (SCs) and relate these differences to performance on functional tasks using a sensory substitution device (BrainPort). Methods: We enrolled 52 subjects (PB n = 11; AB n = 35; SC n = 6). All subjects spent 15 h undergoing BrainPort device training. Outcomes of light perception, motion, direction, temporal resolution, grating, and acuity were tested at baseline and after training. Twenty-six of the subjects were scanned with a three Tesla MRI scanner for diffusion tensor imaging (DTI), and with a positron emission tomography (PET) scanner for mapping regional brain glucose consumption during sensory substitution function. Non-parametric models were used to analyze fractional anisotropy (FA; a DTI measure of microstructural integrity) of the brain via region-of-interest (ROI) analysis and tract-based spatial statistics (TBSS). Results: At baseline, all subjects performed all tasks at chance level. After training, light perception, time resolution, location and grating acuity tasks improved significantly for all subject groups. ROI and TBSS analyses of FA maps show areas of statistically significant differences (p ? 0.025) in the bilateral optic radiations and some visual association connections between all three groups. No relationship was found between FA and functional performance with the BrainPort. Discussion: All subjects showed performance improvements using the BrainPort irrespective of nature and duration of blindness. Definite brain areas with significant microstructural integrity changes exist among PB, AB, and NC, and these variations are most pronounced in the visual pathways. However, the use of sensory substitution devices is feasible irrespective of microstructural integrity of the primary visual pathways between the eye and the brain. Therefore, tongue based devices devices may be usable for a broad array of non-sighted patients. PMID:24860473

Lee, Vincent K.; Nau, Amy C.; Laymon, Charles; Chan, Kevin C.; Rosario, Bedda L.; Fisher, Chris

2014-01-01

195

[Autoimmune autonomic ganglionopathy and acute autonomic and sensory neuropathy].  

PubMed

Autonomic neuropathies may occur primarily or secondarily to various underlying diseases. Primary autonomic neuropathies are divided into pure autonomic neuropathy, autonomic neuropathy with sensory impairment, and autonomic neuropathy with sensory and motor impairment based on the concomitance or absence of sensory or motor dysfunctions. Autoimmune autonomic ganglionopathy refers to a pure autonomic neuropathy, which typically affects both cholinergic and adrenergic functions. About a half of the patients with autoimmune autonomic ganglionopathy are positive for anti-ganglionic acetylcholine receptor antibodies. The mode of progression widely ranges from acute to chronic, including that mimicking pure autonomic failure. The number of unmyelinated fibers in the sural nerve biopsy specimens tends to decrease with the duration of disease become longer. Immunomodulatory treatments are suggested to be effective for autoimmune autonomic ganglionopathy. Acute autonomic and sensory neuropathy is characterized by autonomic and sensory impairment without motor dysfunction that reaches its nadir within a short period of time mimicking the progression of Guillain-Barré syndrome. The monophasic clinical course and frequent presence of a history of antecedent infections suggests a participation of immune mechanisms. The initial symptoms are those related to autonomic disturbance or superficial sensory impairment, while deep sensory impairment accompanied by sensory ataxia subsequently appears in some patients. Sural nerve biopsy specimens reveal small-fiber predominant axonal loss, and autopsy cases show neuronal loss in the thoracic sympathetic and dorsal root ganglia. Hence, small neurons in the autonomic and sensory ganglia may be affected in the initial phase and, subsequently, large neurons in the sensory ganglia are damaged in acute autonomic and sensory neuropathy. PMID:24291976

Koike, Haruki; Sobue, Gen

2013-01-01

196

Relationship of sensory organization to balance function in patients with hemiplegia.  

PubMed

Standing balance and dynamic weight shifting were evaluated in 10 subjects with hemiplegia using a sensory organization balance test (SOT) and the Fugl-Meyer sensorimotor assessment (FMSA). The SOT is a timed balance test that evaluates somatosensory, visual, and vestibular function for maintenance of upright posture. In contrast, the FMSA is a functional status assessment that indicates the amount of assistance needed during various balance tasks and the tolerated duration of the task. The results of both clinical tests were compared to determine whether the SOT correlated with functional ability. The SOT scores were significantly correlated with the FMSA balance subscores and the FMSA total lower extremity scores. Based on the results of this preliminary study, the authors concluded that the SOT may be useful for evaluating a patient's functional status. Further implications for the evaluation and treatment of balance dysfunction in persons with hemiplegia are discussed. PMID:2392483

Di Fabio, R P; Badke, M B

1990-09-01

197

OPA1 functions in mitochondria and dysfunctions in optic nerve  

Microsoft Academic Search

OPA1 is the major gene responsible for Dominant Optic Atrophy (DOA), a blinding disease that affects specifically the retinal ganglion cells (RGCs), which function consists in connecting the neuro-retina to the brain. OPA1 encodes an intra-mitochondrial dynamin, involved in inner membrane structures and ubiquitously expressed, raising the critical question of the origin of the disease pathophysiology. Here, we review the

Guy Lenaers; Pascal Reynier; Ghizlane ElAchouri; Chadi Soukkarieh; Aurélien Olichon; Pascale Belenguer; Laurent Baricault; Bernard Ducommun; Christian Hamel; Cécile Delettre

2009-01-01

198

A Gain-of-Function Screen for Genes That Affect the Development of the Drosophila Adult External Sensory Organ  

Microsoft Academic Search

The Drosophila adult external sensory organ, comprising a neuron and its support cells, is derived from a single precursor cell via several asymmetric cell divisions. To identify molecules involved in sensory organ development, we conducted a tissue-specific gain-of-function screen. We screened 2293 independent P-element lines established by P. Rørth and identified 105 lines, carrying insertions at 78 distinct loci, that

Salim Abdelilah-Seyfried; Yee-Ming Chan; Chaoyang Zeng; Nicholas J. Justice; Susan Younger-Shepherd; Linda E. Sharp; Sandra Barbel; Sarah A. Meadows; Lily Yeh Jan; Yuh Nung Jan

199

Effect of extracorporeal shock wave therapy on denervation atrophy and function caused by sciatic nerve injury.  

PubMed

[Purpose] The present study examined the effects of treatment using extracorporeal shock wave therapy (ESWT) on the muscle weight and function of the hind limb in sciatic nerve injury. [Subjects] Forty rats with sciatic nerve crushing injury were randomly divided into two groups: an ESWT group (n=20), and a control group (n=20). [Methods] The ESWT group received extracorporeal shock wave treatment, and the control group did not receive any treatment after injury. Experimental animals were measured for muscle weight on an electronic scale and were tested for function on a sciatic functional index (SFI). [Results] All groups showed significant increases in the weights of the left soleus and gastrocnemius muscles, and decreases in the weights of the right soleus and gastrocnemius muscles (p<0.05). Comparison of SFI scores and muscle weights between the groups showed significant differences in SFI scores, and the right soleus and gastrocnemius muscles (p<0.05) [Conclusion] Exercise programs that use ESWT can be said to be effective at improving the function of the sciatic nerve and preventing the denervation atrophy. PMID:24259917

Lee, Jung-Ho; Cho, Sung-Hyoun

2013-09-01

200

Peripheral nerve functions in chronic alcoholic patients on disulfiram: a six month follow up.  

PubMed Central

The peripheral nerve functions of chronic alcoholic patients were studied clinically and electrophysiologically before they were placed on disulfiram (Antabuse). The evaluations were repeated while they were treated with 250 mg (n = 33) and 125 mg (n = 9) of disulfiram for one, three and six months. The data were compared with that of 24 untreated chronic alcoholic patients. None of the patients developed overt symptoms of peripheral neuropathy during the period of study. The patients on 250 mg disulfiram showed a significant decline in several components of the peripheral nerve functions, but no significant electrophysiological abnormalities were noted in patients taking 125 mg of disulfiram. Interestingly, the control group showed a significant electrophysiological improvement during the same period of observation. PMID:2157819

Palliyath, S K; Schwartz, B D; Gant, L

1990-01-01

201

NEUROPHYSIOLOGICAL EVALUATION OF SENSORY SYSTEMS'  

EPA Science Inventory

Exposure to many neurotoxic compounds has been shown to produce a sensory system dysfunction. Neurophysiological assessment of sensory function in humans and animal models often uses techniques known as sensory evoked potentials. Because both humans and animals show analogous res...

202

The Role of Cutaneous Innervation in the Sensory Abnormalities Associated with Diabetic Neuropathy  

E-print Network

Diabetes-induced nerve damage results in cutaneous denervation, nerve conduction slowing, suppressed regenerative responses, and debilitating painful or insensate sensory symptoms. The increasing prevalence of diabetic ...

Johnson, Megan Sarah

2008-05-05

203

Scanning pattern of diffusion tensor tractography and an analysis of the morphology and function of spinal nerve roots  

PubMed Central

Radiculopathy, commonly induced by intervertebral disk bulging or protrusion, is presently diagnosed in accordance with clinical symptoms because there is no objective quantitative diagnostic criterion. Diffusion tensor magnetic resonance imaging and diffusion tensor tractography revealed the characterization of anisotropic diffusion and displayed the anatomic form of nerve root fibers. This study included 18 cases with intervertebral disc degeneration-induced unilateral radiculopathy. Magnetic resonance diffusion tensor imaging was creatively used to reveal the scanning pattern of fiber tracking of the spinal nerve root. A scoring system of nerve root morphology was used to quantitatively assess nerve root morphology and functional alteration after intervertebral disc degeneration. Results showed that after fiber tracking, compared with unaffected nerve root, fiber bundles gathered together and interrupted at the affected side. No significant alteration was detected in the number of fiber bundles, but the cross-sectional area of nerve root fibers was reduced. These results suggest that diffusion tensor magnetic resonance imaging-based tractography can be used to quantitatively evaluate nerve root function according to the area and morphology of fiber bundles of nerve roots. PMID:25206637

Tian, Xin; Liu, Huaijun; Geng, Zuojun; Yang, Hua; Wang, Guoshi; Yang, Jiping; Wang, Chunxia; Li, Cuining; Li, Ying

2013-01-01

204

A comparative morphological, electrophysiological and functional analysis of axon regeneration through peripheral nerve autografts genetically modified to overexpress BDNF, CNTF, GDNF, NGF, NT3 or VEGF.  

PubMed

The clinical outcome of microsurgical repair of an injured peripheral nerve with an autograft is suboptimal. A key question addressed here is: can axon regeneration through an autograft be further improved? In this article the impact of six neurotrophic factors (BDNF, CNTF, GDNF, NGF, NT3 or VEGF) on axon regeneration was compared after delivery to a 1cm long nerve autograft by gene therapy. To distinguish between early and late effects, regeneration was assessed at 2 and 20weeks post-surgery by histological, electrophysiological and functional analysis. BDNF, GDNF and NGF exhibited a spectrum of effects, including early stimulatory effects on axons entering the autograft and excessive axon growth and Schwann cell proliferation at 20weeks post-surgery. Persistent expression of these factors in autografts interfered with target cell reinnervation and functional recovery in a modality specific way. Autografts overexpressing VEGF displayed hypervascularization, while grafts transduced with CNTF and NT3 were indistinguishable from control grafts. These three factors did not have detectable pro-regenerative effects. In conclusion, autograft-based repair combined with gene therapy for three of the six growth factors investigated (BDNF, GDNF, NGF) showed considerable promise since these factors enhanced modality specific axon outgrowth in autografts. The remarkable and selective effects of BDNF, GDNF and NGF on motor or sensory regeneration will be exploited in future experiments that aim to carefully regulate their temporal and spatial expression since this has the potential to overcome the adverse effects on long-distance regeneration observed after uncontrolled delivery. PMID:25128265

Hoyng, Stefan A; De Winter, Fred; Gnavi, Sara; de Boer, Ralph; Boon, Lennard I; Korvers, Laura M; Tannemaat, Martijn R; Malessy, Martijn J A; Verhaagen, Joost

2014-11-01

205

Differences in risk factors for neurophysiologically confirmed carpal tunnel syndrome and illness with similar symptoms but normal median nerve function: a case–control study  

PubMed Central

Background To explore whether risk factors for neurophysiologically confirmed carpal tunnel syndrome (CTS) differ from those for sensory symptoms with normal median nerve conduction, and to test the validity and practical utility of a proposed definition for impaired median nerve conduction, we carried out a case–control study of patients referred for investigation of suspected CTS. Methods We compared 475 patients with neurophysiological abnormality (NP+ve) according to the definition, 409 patients investigated for CTS but classed as negative on neurophysiological testing (NP-ve), and 799 controls. Exposures to risk factors were ascertained by self-administered questionnaire. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated by logistic regression. Results NP+ve disease was associated with obesity, use of vibratory tools, repetitive movement of the wrist or fingers, poor mental health and workplace psychosocial stressors. NP-ve illness was also related to poor mental health and occupational psychosocial stressors, but differed from NP+ve disease in showing associations also with prolonged use of computer keyboards and tendency to somatise, and no relation to obesity. In direct comparison of NP+ve and NP-ve patients (the latter being taken as the reference category), the most notable differences were for obesity (OR 2.7, 95 % CI 1.9-3.9), somatising tendency (OR 0.6, 95% CI 0.4-0.9), diabetes (OR 1.6, 95% CI 0.9-3.1) and work with vibratory tools (OR 1.4, 95% CI 0.9-2.2). Conclusions When viewed in the context of earlier research, our findings suggest that obesity, diabetes, use of hand-held vibratory tools, and repeated forceful movements of the wrist and hand are causes of impaired median nerve function. In addition, sensory symptoms in the hand, whether from identifiable pathology or non-specific in origin, may be rendered more prominent and distressing by hand activity, low mood, tendency to somatise, and psychosocial stressors at work. These differences in associations with risk factors support the validity of our definition of impaired median nerve conduction. PMID:23947720

2013-01-01

206

Effect of in situ delivery of acetyl-L-carnitine on peripheral nerve regeneration and functional recovery in transected sciatic nerve in rat.  

PubMed

The repair of peripheral nerve injuries is still one of the most challenging tasks and concerns in neurosurgery, plastic and orthopedic surgery. Effect of acetyl-L-carnitine (ALC) loaded chitosan conduit as an in situ delivery system of ALC in bridging the defects was studied using a rat sciatic nerve regeneration model. A 10-mm sciatic nerve defect was bridged using a chitosan conduit (CHIT/ALC) filled with 10 ?L ALC (100 ng/mL). In control group (CHIT), the conduit was filled with the same volume of the phosphate buffered solution. The regenerated fibers were studied 4, 8, 12 and 16 weeks after surgery. The functional and electrophysiological studies confirmed faster recovery of the regenerated axons in ALC treated than control group (P < 0.05). The mean ratios of gastrocnemius muscles weight were measured. There was statistically significant difference between the muscle weight ratios of CHIT/ALC and CHIT groups (P<0.05). Morphometric indices of regenerated fibers showed number and diameter of the myelinated fibers in CHIT/ALC were significantly higher than in control group. In immuohistochemistry, the location of reactions to S-100 in CHIT/ALC was clearly more positive than CHIT group. ALC when loaded in a chitosan conduit resulted in improvement of functional recovery and quantitative morphometric indices of sciatic nerve. PMID:25448663

Farahpour, Mohammad Reza; Ghayour, Sina Jangkhahe

2014-12-01

207

Functional and anatomical characteristics of the nerve-brown adipose interaction in the rat  

NASA Technical Reports Server (NTRS)

Experiments were conducted on 12 male rats to study the coupling of signals from the sympathetic nervous system to the brown adipose tissue. Analysis of electron photomicrographs revealed considerable morphological heterogeneity among the nerves entering and leaving the interscapular fat pad. In response to electrical simulation of the nerves, the temperature of the brown fat increased following a rapid but transient temperature drop. Such changes were observed only on the ipsilateral side, indicating that the innervation to the interscapular brown fat of the rat is functionally bilateral rather than diffuse. The finding that brown fat is capable of responding in a graded fashion correlates well with observations suggesting that clusters of brown adipocytes may be electrically coupled.

Flaim, K. E.; Horowitz, J. M.; Horwitz, B. A.

1976-01-01

208

Intramuscular nerve distribution in bladder and the relationship between intramuscular ganglia and bladder function in man and dog  

PubMed Central

In clinical, the relationship between bladder intramuscular nerve and function is also elusive. This study aims to compare the bladder intramuscular nerve distribution and its characteristics and significance in human and dog. Eleven dogs’ bladders were stained by Sihler’s and HE techniques. Fifteen human bladders were adopted by Sihler’s staining, using 10% formaldehyde to fix 12 weeks, 7 by HE dyeing fixes 24 hours. Results indicated that man’s bladder was triangularpyramid-shaped. While dog’s bladder was spherical-shaped and its muscle fibers arrange were irregularly shaped. Longitudinal muscle of the outer layer is fleshy, the terminal is at the bladder neck without exception, and vesical trigone has relatively obvious three layers of structure. After dyeing dog’s bladder was transparent jelly, the nerve was purple color, enter bladder at the ureter-bladder junction with different forms. Man’s bladder nerves, no ganglion, were more trivial than that of dogs, and with smaller branches, the large nerve ganglion. The links with the nerve fibers and forms the network on the dog’s bladder wall, and the nerve fibers crosses comparatively little on both the left and right sides in the midline. The right nerve branch gains advantage on the man’s bladder wall, the situations is opposite on the dog’s. In conclusion, bladder nerves which scatter to the bladder wall have branches to lower ureter at the ureter-bladder junction, the structure and distribution of intramuscular nerves are different, the existence of intramuscular ganglia is relating to the bladder function both in man and dog.

Zhao, Zeju; Xu, Qian; Lu, Li; Luo, Xu; Fu, Xiaoyun

2014-01-01

209

Use of Vein Conduit and Isolated Nerve Graft in Peripheral Nerve Repair: A Comparative Study  

PubMed Central

Aims and Objectives. The aim of this study was to evaluate the effectiveness of vein conduit in nerve repair compared with isolated nerve graft. Materials and Methods. This retrospective study was conducted at author's centre and included a total of 40 patients. All the patients had nerve defect of more than 3?cm and underwent nerve repair using nerve graft from sural nerve. In 20 cases, vein conduit (study group) was used whereas no conduit was used in other 20 cases. Patients were followed up for 2 years at the intervals of 3 months. Results. Patients had varying degree of recovery. Sensations reached to all the digits at 1 year in study groups compared to 18 months in control group. At the end of second year, 84% patients of the study group achieved 2-point discrimination of <10?mm compared to 60% only in control group. In terms of motor recovery, 82% patients achieved satisfactory hand function in study group compared to 56% in control group (P < .05). Conclusions. It was concluded that the use of vein conduit in peripheral nerve repair is more effective method than isolated nerve graft providing good sensory and motor recovery. PMID:25405029

Ahmad, Imran; Akhtar, Md. Sohaib

2014-01-01

210

Sensory integration dysfunction affects efficacy of speech therapy on children with functional articulation disorders  

PubMed Central

Background Articulation disorders in young children are due to defects occurring at a certain stage in sensory and motor development. Some children with functional articulation disorders may also have sensory integration dysfunction (SID). We hypothesized that speech therapy would be less efficacious in children with SID than in those without SID. Hence, the purpose of this study was to compare the efficacy of speech therapy in two groups of children with functional articulation disorders: those without and those with SID. Method: A total of 30 young children with functional articulation disorders were divided into two groups, the no-SID group (15 children) and the SID group (15 children). The number of pronunciation mistakes was evaluated before and after speech therapy. Results: There were no statistically significant differences in age, sex, sibling order, education of parents, and pretest number of mistakes in pronunciation between the two groups (P > 0.05). The mean and standard deviation in the pre- and post-test number of mistakes in pronunciation were 10.5 ± 3.2 and 3.3 ± 3.3 in the no-SID group, and 10.1 ± 2.9 and 6.9 ± 3.5 in the SID group, respectively. Results showed great changes after speech therapy treatment (F = 70.393; P < 0.001) and interaction between the pre/post speech therapy treatment and groups (F = 11.119; P = 0.002). Conclusions: Speech therapy can improve the articulation performance of children who have functional articulation disorders whether or not they have SID, but it results in significantly greater improvement in children without SID. SID may affect the treatment efficiency of speech therapy in young children with articulation disorders. PMID:23355780

Tung, Li-Chen; Lin, Chin-Kai; Hsieh, Ching-Lin; Chen, Ching-Chi; Huang, Chin-Tsan; Wang, Chun-Hou

2013-01-01

211

Influence of putrescine and carnauba wax on functional and sensory quality of pomegranate (Punica granatum L.) fruits during storage.  

PubMed

Functional properties (anthocyanins, antioxidant, ascorbic acid and tannin) and sensory score were determined in pomegranate fruits at two storage temperatures (3 and 5 °C) after treatment with 2 mM putrescine and 1 : 10 carnauba wax (carnauba wax : water). The treatments (putrescine and carnauba wax) were given by immersion method followed by storage up to 60 days. Both treatments retained significantly higher anthocyanins, antioxidant, ascorbic acid, tannin and sensory qualities as compared with control fruits under both the storage conditions. Combined application of putrescine + carnauba wax showed better response in retaining functional properties than putrescine treated or nontreated fruits. The impacts of putrescine and carnauba wax treatments were found more pronounced after 30 days at 3-5 °C storage temperature in retaining functional and sensory qualities. After 60 days of storage, putrescine + carnauba wax retained about 25% higher antioxidant activity both at 3 and 5 °C storage temperatures. PMID:24426055

Barman, Kalyan; Asrey, Ram; Pal, R K; Kaur, Charanjit; Jha, S K

2014-01-01

212

Functional consequences of structural differences in stingray sensory systems. Part I: mechanosensory lateral line canals.  

PubMed

Short range hydrodynamic and electrosensory signals are important during final stages of prey capture in elasmobranchs (sharks, skates and rays), and may be particularly useful for dorso-ventrally flattened batoids with mouths hidden from their eyes. In stingrays, both the lateral line canal and electrosensory systems are highly modified and complex with significant differences on ventral surfaces that relate to feeding ecology. This study tests functional hypotheses based on quantified differences in sensory system morphology of three stingray species, Urobatis halleri, Myliobatis californica and Pteroplatytrygon violacea. Part I investigates the mechanosensory lateral line canal system whereas part II focuses on the electrosensory system. Stingray lateral line canals include both pored and non-pored sections and differ in branching complexity and distribution. A greater proportion of pored canals and high pore numbers were predicted to correspond to increased response to water flow. Behavioral experiments were performed to compare responses of stingrays to weak water jets mimicking signals produced by potential prey at velocities of 10-20 cm s(-1). Bat rays, M. californica, have the most complex and broadly distributed pored canal network and demonstrated both the highest response rate and greater response intensity to water jet signals. Results suggest that U. halleri and P. violacea may rely on additional sensory input, including tactile and visual cues, respectively, to initiate stronger feeding responses. These results suggest that stingray lateral line canal morphology can indicate detection capabilities through responsiveness to weak water jets. PMID:19749095

Jordan, Laura K; Kajiura, Stephen M; Gordon, Malcolm S

2009-10-01

213

Drosophila Notch Receptor Activity Suppresses Hairless Function during Adult External Sensory Organ Development  

PubMed Central

The neurogenic Notch locus of Drosophila encodes a receptor necessary for cell fate decisions within equivalence groups, such as proneural clusters. Specification of alternate fates within clusters results from inhibitory communication among cells having comparable neural fate potential. Genetically, Hairless (H) acts as an antagonist of most neurogenic genes and may insulate neural precursor cells from inhibition. H function is required for commitment to the bristle sensory organ precursor (SOP) cell fate and for daughter cell fates. Using Notch gain-of-function alleles and conditional expression of an activated Notch transgene, we show that enhanced signaling produces H-like loss-of-function phenotypes by suppressing bristle SOP cell specification or by causing an H-like transformation of sensillum daughter cell fates. Furthermore, adults carrying Notch gain of function and H alleles exhibit synergistic enhancement of mutant phenotypes. Over-expression of an H(+) transgene product suppressed virtually all phenotypes generated by Notch gain-of-function genotypes. Phenotypes resulting from over-expression of the H(+) transgene were blocked by the Notch gain-of-function products, indicating a balance between Notch and H activity. The results suggest that H insulates SOP cells from inhibition and indicate that H activity is suppressed by Notch signaling. PMID:8601489

Lyman, D. F.; Yedvobnick, B.

1995-01-01

214

Sensing the Underground – Ultrastructure and Function of Sensory Organs in Root-Feeding Melolontha melolontha (Coleoptera: Scarabaeinae) Larvae  

PubMed Central

Introduction Below ground orientation in insects relies mainly on olfaction and taste. The economic impact of plant root feeding scarab beetle larvae gave rise to numerous phylogenetic and ecological studies. Detailed knowledge of the sensory capacities of these larvae is nevertheless lacking. Here, we present an atlas of the sensory organs on larval head appendages of Melolontha melolontha. Our ultrastructural and electrophysiological investigations allow annotation of functions to various sensory structures. Results Three out of 17 ascertained sensillum types have olfactory, and 7 gustatory function. These sensillum types are unevenly distributed between antennae and palps. The most prominent chemosensory organs are antennal pore plates that in total are innervated by approximately one thousand olfactory sensory neurons grouped into functional units of three-to-four. In contrast, only two olfactory sensory neurons innervate one sensillum basiconicum on each of the palps. Gustatory sensilla chaetica dominate the apices of all head appendages, while only the palps bear thermo-/hygroreceptors. Electrophysiological responses to CO2, an attractant for many root feeders, are exclusively observed in the antennae. Out of 54 relevant volatile compounds, various alcohols, acids, amines, esters, aldehydes, ketones and monoterpenes elicit responses in antennae and palps. All head appendages are characterized by distinct olfactory response profiles that are even enantiomer specific for some compounds. Conclusions Chemosensory capacities in M. melolontha larvae are as highly developed as in many adult insects. We interpret the functional sensory units underneath the antennal pore plates as cryptic sensilla placodea and suggest that these perceive a broad range of secondary plant metabolites together with CO2. Responses to olfactory stimulation of the labial and maxillary palps indicate that typical contact chemo-sensilla have a dual gustatory and olfactory function. PMID:22848471

Hansson, Bill S.; Hilker, Monika; Reinecke, Andreas

2012-01-01

215

Treadmill Exercise Induced Functional Recovery after Peripheral Nerve Repair Is Associated with Increased Levels of Neurotrophic Factors  

PubMed Central

Benefits of exercise on nerve regeneration and functional recovery have been reported in both central and peripheral nervous system disease models. However, underlying molecular mechanisms of enhanced regeneration and improved functional outcomes are less understood. We used a peripheral nerve regeneration model that has a good correlation between functional outcomes and number of motor axons that regenerate to evaluate the impact of treadmill exercise. In this model, the median nerve was transected and repaired while the ulnar nerve was transected and prevented from regeneration. Daily treadmill exercise resulted in faster recovery of the forelimb grip function as evaluated by grip power and inverted holding test. Daily exercise also resulted in better regeneration as evaluated by recovery of compound motor action potentials, higher number of axons in the median nerve and larger myofiber size in target muscles. Furthermore, these observations correlated with higher levels of neurotrophic factors, glial derived neurotrophic factor (GDNF), brain derived neurotrophic factor (BDNF) and insulin-like growth factor-1 (IGF-1), in serum, nerve and muscle suggesting that increase in muscle derived neurotrophic factors may be responsible for improved regeneration. PMID:24618564

Park, Jae-Sung; Höke, Ahmet

2014-01-01

216

[Regeneration of the facial nerve in comparison to other peripheral nerves : from bench to bedside].  

PubMed

Despite increasing knowledge of cellular and molecular mechanisms determining the success or failure of peripheral nerve regeneration, no effective treatments for peripheral nerve injury exist. Newly developed and validated approaches for precise numerical assessment of motor deficits have recently allowed testing of novel strategies in experimental animals. One of these approaches is the daily manual stimulation of the denervated musculature. This treatment is effective in cases of cranial nerve lesions with preservation of the sensory input (facial or hypoglossal nerve) and has the potential of direct translation in clinical settings. However, manual stimulation appears to be ineffective for the treatment of mixed peripheral nerve injuries. Generally, no long-term improvement of functional recovery is achieved by electrical stimulation in rodents. While short-term post-traumatic stimulation of the proximal nerve stump has no negative effects, direct electrical stimulation of the muscle during the period of de- and reinnervation appears to hinder muscle fibre reinnervation. Finally, experimental evidence suggests that application of peptides known as glycomimetics, which mimic functional properties of carbohydrate molecules, may provide significant benefits after injuries of mixed peripheral nerves. PMID:20454881

Irintchev, A; Angelov, D N; Guntinas-Lichius, O

2010-05-01

217

Conserved Dopamine Neurotrophic Factor-Transduced Mesenchymal Stem Cells Promote Axon Regeneration and Functional Recovery of Injured Sciatic Nerve  

PubMed Central

Peripheral nerve injury (PNI) is a common disease that often results in axonal degeneration and the loss of neurons, ultimately leading to limited nerve regeneration and severe functional impairment. Currently, there are no effective treatments for PNI. In the present study, we transduced conserved dopamine neurotrophic factor (CDNF) into mesenchymal stem cells (MSCs) in collagen tubes to investigate their regenerative effects on rat peripheral nerves in an in vivo transection model. Scanning electron microscopy of the collagen tubes demonstrated their ability to be resorbed in vivo. We observed notable overexpression of the CDNF protein in the distal sciatic nerve after application of CDNF-MSCs. Quantitative analysis of neurofilament 200 (NF200) and S100 immunohistochemistry showed significant enhancement of axonal and Schwann cell regeneration in the group receiving CDNF-MSCs (CDNF-MSCs group) compared with the control groups. Myelination thickness, axon diameter and the axon-to fiber diameter ratio (G-ratio) were significantly higher in the CDNF-MSCs group at 8 and 12 weeks after nerve transection surgery. After surgery, the sciatic functional index, target muscle weight, wet weight ratio of gastrocnemius muscle and horseradish peroxidase (HRP) tracing demonstrated functional recovery. Light and electron microscopy confirmed successful regeneration of the sciatic nerve. The greater numbers of HRP-labeled neuron cell bodies and increased sciatic nerve index values (SFI) in the CDNF-MSCs group suggest that CDNF exerts neuroprotective effects in vivo. We also observed higher target muscle weights and a significant improvement in muscle atrophism in the CDNF-MSCs group. Collectively, these findings indicate that CDNF gene therapy delivered by MSCs is capable of promoting nerve regeneration and functional recovery, likely because of the significant neuroprotective and neurotrophic effects of CDNF and the superior environment offered by MSCs and collagen tubes. PMID:25343619

Liu, Yi; Nie, Lin; Zhao, Hua; Zhang, Wen; Zhang, Yuan-Qiang; Wang, Shuai-Shuai; Cheng, Lei

2014-01-01

218

Repair of peripheral nerve with vein wrapping*  

PubMed Central

Objective The post–traumatic neuro-anastomosis must be protected from the surrounding environment. This barrier must be biologically inert, biodegradable, not compressing but protecting the nerve. Formation of painful neuroma is one of the major issues with neuro-anastomosis; currently there is no consensus on post-repair neuroma prevention. Aim of this study is to evaluate the efficacy of neuroanastomosis performed with venous sheath to reduce painful neuromas formation, improve the electrical conductivity of the repaired nerve, and reduce the discrepancies of the sectioned nerve stumps. Patients and methods From a trauma population of 320 patients treated in a single centre between January 2008 and December 2011, twenty-six patients were identified as having an injury to at least one of the peripheral nerves of the arm and enrolled in the study. Patients were divided into two groups. In the group A (16 patients) the end-to-end nerve suture was wrapped in a vein sheath and compared with the group B (10 patients) in which a simple end-to-end neurorrhaphy was performed. The venous segment used to cover the nerve micro-suture was harvested from the superficial veins of the forearm. The parameters analyzed were: functional recovery of motor nerves, sensitivity and pain. Results Average follow-up was 14 months (range: 12–24 months). The group A showed a more rapid motor and sensory recovery and a reduction of the painful symptoms compared to the control group (B). Conclusions The Authors demonstrated that, in their experience, the venous sheath provides a valid solution to avoid the dispersion of the nerve fibres, to prevent adherent scars and painful neuromas formation. Moreover it can compensate the different size of two nerve stumps, allowing, thereby, a more rapid functional and sensitive recovery without expensive devices. PMID:24841688

LEUZZI, S.; ARMENIO, A.; LEONE, L.; DE SANTIS, V.; DI TURI, A.; ANNOSCIA, P.; BUFANO, L.; PASCONE, M.

2014-01-01

219

Quantitative parameters of facial motor evoked potential during vestibular schwannoma surgery predict postoperative facial nerve function  

Microsoft Academic Search

Background  Facial motor evoked potential (FMEP) amplitude ratio reduction at the end of the surgery has been identified as a good predictor\\u000a for postoperative facial nerve outcome. We sought to investigate variations in FMEP amplitude and waveform morphology during\\u000a vestibular schwannoma (VS) resection and to correlate these measures with postoperative facial function immediately after\\u000a surgery and at the last follow-up.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Intraoperative

Marcus André Acioly; Alireza Gharabaghi; Marina Liebsch; Carlos Henrique Carvalho; Paulo Henrique Aguiar; Marcos Tatagiba

2011-01-01

220

Single session of brief electrical stimulation immediately following crush injury enhances functional recovery of rat facial nerve.  

PubMed

Peripheral nerve injuries lead to a variety of pathological conditions, including paresis or paralysis when the injury involves motor axons. We have been studying ways to enhance the regeneration of peripheral nerves using daily electrical stimulation (ES) following a facial nerve crush injury. In our previous studies, ES was not initiated until 24 h after injury. The current experiment tested whether ES administered immediately following the crush injury would further decrease the time for complete recovery from facial paralysis. Rats received a unilateral facial nerve crush injury and an electrode was positioned on the nerve proximal to the crush site. Animals received daily 30 min sessions of ES for 1 d (day of injury only), 2 d, 4 d, 7 d, or daily until complete functional recovery. Untreated animals received no ES. Animals were observed daily for the return of facial function. Our findings demonstrated that one session of ES was as effective as daily stimulation at enhancing the recovery of most functional parameters. Therefore, the use of a single 30 min session of ES as a possible treatment strategy should be studied in human patients with paralysis as a result of acute nerve injuries. PMID:22773203

Foecking, Eileen M; Fargo, Keith N; Coughlin, Lisa M; Kim, James T; Marzo, Sam J; Jones, Kathryn J

2012-01-01

221

Surveillance of the gastrointestinal mucosa by sensory neurons.  

PubMed

A dense network of extrinsic and intrinsic sensory neurons supplies the gastrointestinal tract. Intrinsic sensory neurons provide the enteric nervous system with the kind of information that this brain of the gut requires for its autonomic control of digestion, whereas extrinsic afferents notify the brain about processes that are relevant to energy and fluid homeostasis and the sensation of discomfort and pain. The sensory repertoire of afferent neurons is extended by their responsiveness to mediators released from enteroendocrine and immune cells, which act like "taste buds" of the gut and serve as interface between the gastrointestinal lumen and the sensory nerve terminals in the lamina propria of the mucosa. Functional bowel disorders such as non-ulcer dyspepsia and irritable bowel syndrome are characterized by abdominal discomfort or pain in the absence of an identifiable organic cause. It is hypothesized with good reason that infection, inflammation or trauma causes sensory pathways to undergo profound phenotypic and functional alterations that outlast the acute insult. The pertinent changes involve an exaggerated sensitivity of the peripheral afferent nerve fibres as well as a distorted processing and representation of the incoming information in the brain. This concept identifies a number of receptors and ion channels that are selectively expressed by primary afferent neurons as important molecular targets at which to aim novel therapies for functional bowel disorders. PMID:11787755

Holzer, P; Michl, T; Danzer, M; Jocic, M; Schicho, R; Lippe, I T

2001-12-01

222

Sudden peroneal nerve palsy in a varus arthritic knee.  

PubMed

Peroneal nerve palsy has been reported in association with traumatic and nontraumatic causes. We encountered a 75-year-old man whose peroneal nerve palsy developed suddenly following varus deformity of the arthritic knee. A review of the literature found 1 other report describing a progressive peroneal nerve palsy associated with a varus deformity of the knee due to arthritis. Our patient had progressive intractable knee pain; 3-compartment, severe degenerative changes in the knees; varus knee malalignment and laxity; right peroneal nerve palsy; and decreased sensation to light touch and pinprick on the dorsum of the right foot. The preoperative WOMAC score was 36. Nerve conduction studies confirmed acute peroneal neuropathy with conduction block at the fibular neck and secondary axonal degeneration. Magnetic resonance imaging of the knee showed osteophytes and cysts surrounding the fibular neck. Although their compression could be responsible for the nerve palsy, the sudden process made this less possible. Thus, the patient underwent total knee arthroplasty of both knees without exploration of the nerve. At 5-month follow-up, the WOMAC score was 78. The patient walked with a cane with no varus thrust, and his right knee had no varus laxity in full extension. The peroneal nerve did not retain its function. Sensory examination and postoperative nerve conduction studies showed no improvement. PMID:19968227

Seyyed Hosseinzadeh, Hamid Reza; Eajazi, Alireza; Kazemi, Seyyed Morteza; Daftari Besheli, Laleh; Hassas Yeganeh, Mehrnoush; Aydanloo, Ali

2009-12-01

223

Muscle Ciliary Neurotrophic Factor Receptor ? Promotes Axonal Regeneration and Functional Recovery Following Peripheral Nerve Lesion  

PubMed Central

Ciliary neurotrophic factor (CNTF) administration maintains, protects, and promotes the regeneration of both motor neurons (MNs) and skeletal muscle in a wide variety of models. Expression of CNTF receptor ? (CNTFR?), an essential CNTF receptor component, is greatly increased in skeletal muscle following neuromuscular insult. Together the data suggest that muscle CNTFR? may contribute to neuromuscular maintenance, protection, and/or regeneration in vivo. To directly address the role of muscle CNTFR?, we selectively-depleted it in vivo by using a “floxed” CNTFR? mouse line and a gene construct (mlc1f-Cre) that drives the expression of Cre specifically in skeletal muscle. The resulting mice were challenged with sciatic nerve crush. Counting of nerve axons and retrograde tracing of MNs indicated that muscle CNTFR? contributes to MN axonal regeneration across the lesion site. Walking track analysis indicated that muscle CNTFR? is also required for normal recovery of motor function. However, the same muscle CNTFR? depletion unexpectedly had no detected effect on the maintenance or regeneration of the muscle itself, even though exogenous CNTF has been shown to affect these functions. Similarly, MN survival and lesion-induced terminal sprouting were unaffected. Therefore, muscle CNTFR? is an interesting new example of a muscle growth factor receptor that, in vivo under physiological conditions, contributes much more to neuronal regeneration than to the maintenance or regeneration of the muscle itself. This novel form of muscle–neuron interaction also has implications in the therapeutic targeting of the neuromuscular system in MN disorders and following nerve injury. PMID:23504871

Lee, Nancy; Spearry, Rachel P.; Leahy, Kendra M.; Robitz, Rachel; Trinh, Dennis S.; Mason, Carter O.; Zurbrugg, Rebekah J.; Batt, Myra K.; Paul, Richard J.; Maclennan, A. John

2014-01-01

224

Changes in nutritional composition, functional, and sensory properties of yam flour as a result of presoaking  

PubMed Central

This study investigated the effect of soaking pretreatments on some of the properties of flour obtained from two varieties of yam namely;Dioscorea alata andDioscorea rotundata with a view of providing information that will enhance their end use. The yam varieties were washed, chipped, parboiled at 50°C, soaked for different periods (0, 6, 12, and 18 h), dried at 60°C, and milled into flour. The flour samples were analyzed for their nutritional composition, pH, color, and functional properties. The flour samples were also made into pastes and were sensorially analyzed and 0 h soaked samples were used as control. The protein content of 18 h-soakedD. rotundata andD. alata flour samples was significantly different from the control and soaking had no effect (P > 0.05) on the fat and ash content but the carbohydrate content of the flour samples ranged from 83.08% to 86.13%. The 18 h-soakedD. rotundata flour sample had the lowest peak viscosity, breakdown value, and final viscosity among theD. rotundata variety samples. Pasting temperature ranged from 79.80 to 83.60°C and 6-h soakedD. alata flour sample had the lowest water absorption capacity and the highest bulk density. On the basis of sensory analysis, the panelist preferred the taste, texture, color, and appearance of paste made from the 18-h soakedD. rotundata flour to the paste of other flour samples. The results of this study show that D.rotundata should be soaked for 18 h prior to drying and milling in order to obtain a good-quality flour and paste. PMID:25493185

Obadina, Adewale Olusegun; Babatunde, Bukunola Olaide; Olotu, Ifeoluwa

2014-01-01

225

Changes in nutritional composition, functional, and sensory properties of yam flour as a result of presoaking.  

PubMed

This study investigated the effect of soaking pretreatments on some of the properties of flour obtained from two varieties of yam namely;Dioscorea alata andDioscorea rotundata with a view of providing information that will enhance their end use. The yam varieties were washed, chipped, parboiled at 50°C, soaked for different periods (0, 6, 12, and 18 h), dried at 60°C, and milled into flour. The flour samples were analyzed for their nutritional composition, pH, color, and functional properties. The flour samples were also made into pastes and were sensorially analyzed and 0 h soaked samples were used as control. The protein content of 18 h-soakedD. rotundata andD. alata flour samples was significantly different from the control and soaking had no effect (P > 0.05) on the fat and ash content but the carbohydrate content of the flour samples ranged from 83.08% to 86.13%. The 18 h-soakedD. rotundata flour sample had the lowest peak viscosity, breakdown value, and final viscosity among theD. rotundata variety samples. Pasting temperature ranged from 79.80 to 83.60°C and 6-h soakedD. alata flour sample had the lowest water absorption capacity and the highest bulk density. On the basis of sensory analysis, the panelist preferred the taste, texture, color, and appearance of paste made from the 18-h soakedD. rotundata flour to the paste of other flour samples. The results of this study show that D.rotundata should be soaked for 18 h prior to drying and milling in order to obtain a good-quality flour and paste. PMID:25493185

Obadina, Adewale Olusegun; Babatunde, Bukunola Olaide; Olotu, Ifeoluwa

2014-11-01

226

Human periodontal ligament stem cells repair mental nerve injury  

PubMed Central

Human periodontal ligament stem cells are easily accessible and can differentiate into Schwann cells. We hypothesized that human periodontal ligament stem cells can be used as an alternative source for the autologous Schwann cells in promoting the regeneration of injured peripheral nerve. To validate this hypothesis, human periodontal ligament stem cells (1 × 106) were injected into the crush-injured left mental nerve in rats. Simultaneously, autologous Schwann cells (1 × 106) and PBS were also injected as controls. Real-time reverse transcriptase polymerase chain reaction showed that at 5 days after injection, mRNA expression of low affinity nerve growth factor receptor was significantaly increased in the left trigeminal ganglion of rats with mental nerve injury. Sensory tests, histomorphometric evaluation and retrograde labeling demonstrated that at 2 and 4 weeks after injection, sensory function was significantly improved, the numbers of retrograde labeled sensory neurons and myelinated axons were significantly increased, and human periodontal ligament stem cells and autologous Schwann cells exhibited similar therapeutic effects. These findings suggest that transplantation of human periodontal ligament stem cells show a potential value in repair of mental nerve injury. PMID:25206604

Li, Bohan; Jung, Hun-Jong; Kim, Soung-Min; Kim, Myung-Jin; Jahng, Jeong Won; Lee, Jong-Ho

2013-01-01

227

Glaucoma progression detection using structural retinal nerve fiber layer measurements and functional visual field points.  

PubMed

Machine learning classifiers were employed to detect glaucomatous progression using longitudinal series of structural data extracted from retinal nerve fiber layer thickness measurements and visual functional data recorded from standard automated perimetry tests. Using the collected data, a longitudinal feature vector was created for each patient's eye by computing the norm 1 difference vector of the data at the baseline and at each follow-up visit. The longitudinal features from each patient's eye were then fed to the machine learning classifier to classify each eye as stable or progressed over time. This study was performed using several machine learning classifiers including Bayesian, Lazy, Meta, and Tree, composing different families. Combinations of structural and functional features were selected and ranked to determine the relative effectiveness of each feature. Finally, the outcomes of the classifiers were assessed by several performance metrics and the effectiveness of structural and functional features were analyzed. PMID:24658239

Yousefi, Siamak; Goldbaum, Michael H; Balasubramanian, Madhusudhanan; Jung, Tzyy-Ping; Weinreb, Robert N; Medeiros, Felipe A; Zangwill, Linda M; Liebmann, Jeffrey M; Girkin, Christopher A; Bowd, Christopher

2014-04-01

228

Biological Actions of Nerve Growth Factor in the Peripheral Nervous System  

Microsoft Academic Search

Since the discovery of nerve growth factor (NGF), its role in the physiology\\/pathophysiology of nerve function has been under intense investigation. More recently, the potential of recombinant human NGF (rhNGF) as a putative treatment for peripheral neuropathies, in particular diabetic polyneuropathy and HIV-associated sensory neuropathy, is being explored. In animal models of diabetes, depletion of endogenous NGF levels has been

Cynthia A. Rask

1999-01-01

229

ELECTROPHYSIOLOGICAL ASSESSMENT OF SENSORY AND COGNITIVE FUNCTION IN CHILDREN EXPOSED TO LEAD: A REVIEW  

EPA Science Inventory

Studies of the effects of lead absorption on sensory evoked and slow brain potentials in children are reviewed. Studies of slow wave voltage in children during sensory conditioning indicated a linear relationship to blood lead level in two studies; an effect that could not be rep...

230

Functional Dissection of the Sensory Rays in Caenorhabditis elegans Male Mating Behavior  

E-print Network

complex of these behaviors and males utilize a number of sensory organs in its execution. Among these are the rays, which are nine pairs of sensory organs that are arranged laterally along the male tail. Each ray is composed of two ultra...

Koo, Pamela Kristine

2012-02-14

231

Effects of polysialic acid on sensory innervation of the cornea.  

PubMed

Sensory trigeminal growth cones innervate the cornea in a coordinated fashion during embryonic development. Polysialic acid (polySia) is known for its important roles during nerve development and regeneration. The purpose of this work is to determine whether polySia, present in developing eyefronts and on the surface of sensory nerves, may provide guidance cues to nerves during corneal innervation. Expression and localization of polySia in embryonic day (E)5-14 chick eyefronts and E9 trigeminal ganglia were identified using Western blotting and immunostaining. Effects of polySia removal on trigeminal nerve growth behavior were determined in vivo, using exogenous endoneuraminidase (endoN) treatments to remove polySia substrates during chick cornea development, and in vitro, using neuronal explant cultures. PolySia substrates, made by the physical adsorption of colominic acid to a surface coated with poly-d-lysine (PDL), were used as a model to investigate functions of the polySia expressed in axonal environments. PolySia was localized within developing eyefronts and on trigeminal sensory nerves. Distributions of PolySia in corneas and pericorneal regions are developmentally regulated. PolySia removal caused defasciculation of the limbal nerve trunk in vivo from E7 to E10. Removal of polySia on trigeminal neurites inhibited neurite outgrowth and caused axon defasciculation, but did not affect Neural Cell Adhesion Molecule (NCAM) expression or Schwann cell migration in vitro. PolySia substrates in vitro inhibited outgrowth of trigeminal neurites and promoted their fasciculation. In conclusion, polySia is localized on corneal nerves and in their targeting environment during early developing stages of chick embryos. PolySias promote fasciculation of trigeminal axons in vivo and in vitro, whereas, in contrast, their removal promotes defasciculation. PMID:25478909

Mao, Xiuli; Zhang, Yuntao; Schwend, Tyler; Conrad, Gary W

2015-02-15

232

Disentangling different functional roles of evoked K-complex components: Mapping the sleeping brain while quenching sensory processing.  

PubMed

During non-REM sleep the largest EEG response evoked by sensory stimulation is the K-complex (eKC), composed of an initial positive bump (P200) followed by a bistable cortical response: a giant negative deflection (N550) and a large positive one (P900), respectively reflecting down states and up states of < 1 Hz oscillations.Sensory-modality-independent topology of N550 and P900, with maximal detection rate on fronto-central areas, has been consistently reported, suggesting that sensory inputs arise to the cortex avoiding specific primary sensory areas. However, these studies neglected latencies of all KC components as a function of electrode sites.Our aim is to identify, component by component, which topological/dynamical properties of eKCs depend on stimulus modality and which are mainly related to local cortical properties. We measured temporal and morphological features of acoustic, tactile and visual eKCs to disentangle specific sensory excitatory activities from aspecific responses due to local proneness to bistability, measured by means of the N550 descending steepness (synchronization in falling into down state).While confirming the sensory-modality independence of N550 and P900 topology with maximal detection rate in fronto-central areas, four main original results emerge from this study: (i) the topology of P200 latency depends on the sensory modality with earliest waves in the stimulation-related primary sensory areas; (ii) P200 rapidly travels as a cortical excitation; (iii) P200-like excitations when KCs are not evoked are detected over the scalp with significantly smaller amplitudes in fronto-central areas, compared to eKC P200s; and (iv) N550 latency mirrors its mean local steepness which is a function of topological proneness to bistability.From these results we can describe the emergence N550/P900 complex as the interplay between a waxing P200 cortical travel and higher fronto-central proneness to bistability.In conclusion, eKCs exhibit a physiological dichotomy: P200 acts as a traveling cortical excitation whose function is to induce the bistable cortical response (N550/P900), which in turn is crucial for maintaining sleep and unconsciousness. PMID:24513527

Laurino, Marco; Menicucci, Danilo; Piarulli, Andrea; Mastorci, Francesca; Bedini, Remo; Allegrini, Paolo; Gemignani, Angelo

2014-02-01

233

Interest of telemicrosurgery in peripheral nerve tumors: about a series of seven cases.  

PubMed

Surgery of the chronic peripheral nerve lesion should not only limit recurrence after excision, but it should also limit the sensory and motor sequelae. The aim of this work was to study the interest of telemicrosurgery to improve this result. Our series included 7 patients with peripheral nerve neuroma and tumors including two cases of hereditary neurofibromatosis. A Da Vinci S(®) robot equipped with microsurgical instruments was used for intraneural dissection. One case was performed with minimally invasive approach. At last follow-up, the pain decreased from 6/10 preoperatively to 3/10 postoperatively. The sensory deficit was stable except for two patients, whose sensory function was improved. No recurrence was noted. Telemicrosurgery seems to have two interests in the treatment of chronic peripheral nerve lesions: it reduces the size of incisions and increases the accuracy of surgery. These preliminary results suggest that surgical robots could play an essential role in microsurgery. PMID:24290701

Tigan, L; Miyamoto, H; Hendriks, S; Facca, S; Liverneaux, P

2014-02-01

234

Reinnervation after nerve suture in rat groin flaps.  

PubMed

Regeneration of sensory and adrenergic nerves in the skin was studied in rats. The aim was to investigate the effect of reanastomosing the cut nerve ends of the nerve trunk leading to the microvascular groin flap. Reinnervation was demonstrated immunohistochemically using calcitonin gene-related peptide (CGRP) as marker for sensory nerves, neuropeptide Y (NPY) and tyrosine hydroxylase (TH) as markers for adrenergic nerves and Protein Gene Product 9.5 (PGP 9.5) as general neuronal marker. It was demonstrated that reanastomosing of the nerve trunk was favourable for both the sensory and sympathetic reinnervation of microsurgical flaps. PMID:9635785

Ranne, J O; Lähteenmäki, P T; Vaalasti, A; Waris, T H; Lindholm, T S

1998-01-01

235

Genetics Home Reference: Hereditary sensory and autonomic neuropathy type V  

MedlinePLUS

... to feel pain, heat, and cold. Deep pain perception, the feeling of pain from injuries to bones, ... gene ; growth factor ; hereditary ; inherited ; joint ; mutation ; neuropathy ; perception ; protein ; receptor ; recessive ; sensory nerve ; sensory neuropathy ; tissue ; ...

236

Effect of an Adipose-Derived Stem Cell and Nerve Growth Factor-Incorporated Hydrogel on Recovery of Erectile Function in a Rat Model of Cavernous Nerve Injury  

PubMed Central

Postprostatectomy erectile dysfunction (ED) is the major problem for patients with clinically localized prostate cancer. Recently, gene and stem cell-based therapy of the corpus cavernosum has been attempted for postprostatectomy ED, but those therapies are limited by rapid blood flow and disruption of the normal architecture of the corpus cavernosum. In this study, we attempted to regenerate the damaged cavernous nerve (CN), which is the main cause of ED. We investigated the effectiveness of human adipose-derived stem cell (hADSC) and nerve growth factor-incorporated hyaluronic acid-based hydrogel (NGF-hydrogel) application on the CN in a rat model of bilateral cavernous nerve crush injury. Four weeks after the operation, erectile function was assessed by detecting the intracavernous pressure (ICP)/arterial pressure level by CN electrostimulation. The ICP was significantly increased by application of hADSC with NGF-hydrogel compared to the other experimental groups. CN and penile tissue were collected for histological examination. PKH-26 labeled hADSC colocalized with beta III tubulin were shown in CN tissue sections. hADSC/NGF-hydrogel treatment prevented smooth muscle atrophy in the corpus cavernosum. In addition, the hADSC/NGF-hydrogel group showed increased endothelial nitric oxide synthase protein expression. This study suggests that application of hADSCs with NGF-hydrogel on the CN might be a promising treatment for postprostatectomy ED. PMID:22834730

Kim, In Gul; Piao, Shuyu; Lee, Ji Young; Hong, Sung Hoo; Hwang, Tae-Kon; Kim, Sae Woong; Kim, Choung Soo; Ra, Jeong Chan; Noh, Insup

2013-01-01

237

Repair of ruptured spinal nerve roots in a brachial plexus lesion. Case report.  

PubMed

A 22-year-old woman sustained a brachial plexus injury with supraganglionic rupture of the C-8 and T-1 nerve roots as a result of a traffic accident. She was operated on approximately 1 week following the accident. After a hemilaminectomy, the intradural defects in the ruptured roots were bridged with sural nerve grafts. Within 3 years she recovered function in all muscles supplied from the lower roots in the plexus except for the intrinsic hand muscles, but she had a persisting, complete sensory loss in the ulnar nerve distribution. The possibility for functional gain after repair of spinal root lesions in brachial plexus patients is discussed. PMID:7897534

Carlstedt, T; Norén, G

1995-04-01

238

High lead exposure and auditory sensory-neural function in Andean children.  

PubMed Central

We investigated blood lead (B-Pb) and mercury (B-Hg) levels and auditory sensory-neural function in 62 Andean school children living in a Pb-contaminated area of Ecuador and 14 children in a neighboring gold mining area with no known Pb exposure. The median B-Pb level for 62 children in the Pb-exposed group was 52.6 micrograms/dl (range 9.9-110.0 micrograms/dl) compared with 6.4 micrograms/dl (range 3.9-12.0 micrograms/dl) for the children in the non-Pb exposed group; the differences were statistically significant (p < 0.001). Auditory thresholds for the Pb-exposed group were normal at the pure tone frequencies of 0.25-8 kHz over the entire range of B-Pb levels, Auditory brain stem response tests in seven children with high B-Pb levels showed normal absolute peak and interpeak latencies. The median B-Hg levels were 0.16 micrograms/dl (range 0.04-0.58 micrograms/dl) for children in the Pb-exposed group and 0.22 micrograms/dl (range 0.1-0.44 micrograms/dl) for children in the non-Pb exposed gold mining area, and showed no significant relationship to auditory function. Images Figure 1. Figure 3. A Figure 3. B PMID:9222138

Counter, S A; Vahter, M; Laurell, G; Buchanan, L H; Ortega, F; Skerfving, S

1997-01-01

239

Mapping a sensory-motor network onto a structural and functional ground plan in the hindbrain  

PubMed Central

The hindbrain of larval zebrafish contains a relatively simple ground plan in which the neurons throughout it are arranged into stripes that represent broad neuronal classes that differ in transmitter identity, morphology, and transcription factor expression. Within the stripes, neurons are stacked continuously according to age as well as structural and functional properties, such as axonal extent, input resistance, and the speed at which they are recruited during movements. Here we address the question of how particular networks among the many different sensory-motor networks in hindbrain arise from such an orderly plan. We use a combination of transgenic lines and pairwise patch recording to identify excitatory and inhibitory interneurons in the hindbrain network for escape behaviors initiated by the Mauthner cell. We map this network onto the ground plan to show that an individual hindbrain network is built by drawing components in predictable ways from the underlying broad patterning of cell types stacked within stripes according to their age and structural and functional properties. Many different specialized hindbrain networks may arise similarly from a simple early patterning. PMID:21199937

Koyama, Minoru; Kinkhabwala, Amina; Satou, Chie; Higashijima, Shin-ichi; Fetcho, Joseph

2011-01-01

240

Improvement of sensorimotor functions in old age by passive sensory stimulation  

PubMed Central

Sensorimotor functions decrease in old age. The well-documented loss of tactile acuity in elderly is accompanied by deterioration of haptic performance and fine manipulative movements. Physical training and exercise can maintain sensorimotor fitness into high age. However, regular schedules of training require discipline and physical fitness. We here present an alternative interventional paradigm to enhance tactile, haptic, and fine motor performance based on passive, sensory stimulation by means of tactile coactivation. This approach is based on patterned, synchronous tactile stimulation applied to the fingertips for 3 hours. The stimulation drives plastic reorganizational changes in somatosensory cortex that affect perception and behavior: We demonstrate that following 3 hours of coactivation tactile acuity as well as haptic object exploration and fine motor performance are improved for at least 96 hours. Because this kind of intervention does not require active participation or attention of the subjects, we anticipate that coactivation is a prime candidate for future therapeutic interventions in patients with impaired sensorimotor abilities. It can be assumed that the maintenance and restoration of sensorimotor functions can ensure and preserve independence of daily living. Further optimizing of the stimulation protocol can be assumed to strengthen both the range and durability of its efficacy. PMID:19281060

Kalisch, Tobias; Tegenthoff, Martin; Dinse, Hubert R

2008-01-01

241

Molecular Evolution of the Infrared Sensory Gene TRPA1 in Snakes and Implications for Functional Studies  

PubMed Central

TRPA1 is a calcium ion channel protein recently identified as the infrared receptor in pit organ-containing snakes. Therefore, understanding the molecular evolution of TRPA1 may help to illuminate the origin of “heat vision” in snakes and reveal the molecular mechanism of infrared sensitivity for TRPA1. To this end, we sequenced the infrared sensory gene TRPA1 in 24 snake species, representing nine snake families and multiple non-snake outgroups. We found that TRPA1 is under strong positive selection in the pit-bearing snakes studied, but not in other non-pit snakes and non-snake vertebrates. As a comparison, TRPV1, a gene closely related to TRPA1, was found to be under strong purifying selection in all the species studied, with no difference in the strength of selection between pit-bearing snakes and non-pit snakes. This finding demonstrates that the adaptive evolution of TRPA1 specifically occurred within the pit-bearing snakes and may be related to the functional modification for detecting infrared radiation. In addition, by comparing the TRPA1 protein sequences, we identified 11 amino acid sites that were diverged in pit-bearing snakes but conserved in non-pit snakes and other vertebrates, 21 sites that were diverged only within pit-vipers but conserved in the remaining snakes. These specific amino acid substitutions may be potentially functional important for infrared sensing. PMID:22163322

Jiang, Ke; Zhang, Peng

2011-01-01

242

Localization of a Passively Transferred Human Recombinant Monoclonal Antibody to Herpes Simplex Virus Glycoprotein D to Infected Nerve Fibers and Sensory Neurons In Vivo  

Microsoft Academic Search

A human recombinant monoclonal antibody to herpes simplex virus (HSV) glycoprotein D labeled with the fluorescent dye Cy5 was administered to mice infected in the cornea with HSV type 1 (HSV-1). The distribution of such antibody in the corneas and trigeminal ganglia of the mice was then investigated by confocal micros- copy. The antibody was detected on HSV-infected nerve fibers

PIETRO PAOLO SANNA; THOMAS J. DEERINCK; MARK H. ELLISMAN

1999-01-01

243

Signals and noise in the octavolateralis systems: What is the impact of human activities on fish sensory function?  

PubMed

The octavolateralis systems of fishes include the vestibular, auditory, lateral line and electrosensory systems. They are united by common developmental and neuro-computational features, including hair cell sensors and computations based on cross-neuron analyses of differential hair cell stimulation patterns. These systems also all use both spectral and temporal filters to separate signals from each other and from noise, and the distributed senses (lateral line and electroreception) add spatial filters as well. Like all sensory systems, these sensors must provide the animal with guidance for adaptive behavior within a sensory scene composed of multiple stimuli and varying levels of ambient noise, including that created by human activities. In the extreme, anthropogenic activities impact the octavolateralis systems by destroying or degrading the habitats that provide ecological resources and sensory inputs. At slightly lesser levels of effect, anthropogenic pollutants can be damaging to fish tissues, with sensory organs often the most vulnerable. The exposed sensory cells of the lateral line and electrosensory systems are especially sensitive to aquatic pollution. At still lesser levels of impact, anthropogenic activities can act as both acute and chronic stressors, activating hormonal changes that may affect behavioral and sensory function. Finally, human activities are now a nearly ubiquitous presence in aquatic habitats, often with no obvious effects on the animals exposed to them. Ship noise, indigenous and industrial fishing techniques, and all the ancillary noises of human civilization form a major part of the soundscape of fishes. How fish use these new sources of information about their habitat is a new and burgeoning field of study. PMID:24920543

Braun, Christopher B

2015-01-01

244

Communication between neuronal somata and satellite glial cells in sensory ganglia.  

PubMed

Studies of the structural organization and functions of the cell body of a neuron (soma) and its surrounding satellite glial cells (SGCs) in sensory ganglia have led to the realization that SGCs actively participate in the information processing of sensory signals from afferent terminals to the spinal cord. SGCs use a variety ways to communicate with each other and with their enwrapped soma. Changes in this communication under injurious conditions often lead to abnormal pain conditions. "What are the mechanisms underlying the neuronal soma and SGC communication in sensory ganglia?" and "how do tissue or nerve injuries affect the communication?" are the main questions addressed in this review. PMID:23918214

Huang, Li-Yen M; Gu, Yanping; Chen, Yong

2013-10-01

245

Effects of Electroacupuncture on Facial Nerve Function and HSV-1 DNA Quantity in HSV-1 Induced Facial Nerve Palsy Mice  

PubMed Central

Acupuncture is a common and effective therapeutic method to treat facial nerve palsy (FNP). However, its underlying mechanism remains unclear. This study was aimed to investigate the effects of electroacupuncture on symptoms and content of HSV-1 DNA in FNP mice. Mice were randomized into four groups, an electroacupuncture treatment group, saline group, model animal group, and blank control group. Electroacupuncture was applied at Jiache (ST6) and Hegu (LI4) in electroacupuncture group once daily for 14 days, while electroacupuncture was not applied in model animal group. In electroacupuncture group, mice recovered more rapidly and HSV-1 DNA content also decreased more rapidly, compared with model animal group. We conclude that electroacupuncture is effective to alleviate symptoms and promote the reduction of HSV-1 in FNP. PMID:24991226

Tang, Hongzhi; Feng, Shuwei; Chen, Jiao; Yang, Mingxiao; Zhong, Zhendong; Li, Ying; Liang, Fanrong

2014-01-01

246

Changes in preganglionic sympathetic nerve function following chronic morphine treatment in rats.  

PubMed Central

1. The effects of acute or chronic morphine treatment on the changes in blood pressure and pulse rate in response to ganglionic stimulation or blockade and to vagal stimulation, and of isolated atria to field stimulation or noradrenaline, were studied. 2. In pithed rats, intravenously injected hexamethonium significantly depressed the blood pressure responses to sympathetic nerve stimulation. The ganglionic blocking effects of hexamethonium were significantly greater in chronically morphine-treated rats, but were not significantly affected by acute morphine administration in naive animals. 3. Intravenous administration of nicotine dose-dependently increased blood pressure and pulse rate. The magnitudes of these changes were not significantly affected by acute or chronic morphine pretreatment. 4. Studies with rat isolated atrial preparations revealed that the changes in atrial contractile rate and force in response to noradrenaline or field stimulation were not influenced by either acute or chronic morphine treatment. 5. Cervical vagal stimulation produced voltage- or frequency-dependent decreases in pulse rate and blood pressure. The responses were not significantly affected by chronic morphine treatment. 6. These findings suggest that the site of the changes in sympathetic function following prolonged exposure to the opiate appears to be on the preganglionic nerve fibres. PMID:1970267

Leung, C. M.; Dai, S.; Ogle, C. W.

1990-01-01

247

Organophosphorus Pesticides Decrease M2 Muscarinic Receptor Function in Guinea Pig Airway Nerves via Indirect Mechanisms  

PubMed Central

Background Epidemiological studies link organophosphorus pesticide (OP) exposures to asthma, and we have shown that the OPs chlorpyrifos, diazinon and parathion cause airway hyperreactivity in guinea pigs 24 hr after a single subcutaneous injection. OP-induced airway hyperreactivity involves M2 muscarinic receptor dysfunction on airway nerves independent of acetylcholinesterase (AChE) inhibition, but how OPs inhibit neuronal M2 receptors in airways is not known. In the central nervous system, OPs interact directly with neurons to alter muscarinic receptor function or expression; therefore, in this study we tested whether the OP parathion or its oxon metabolite, paraoxon, might decrease M2 receptor function on peripheral neurons via similar direct mechanisms. Methodology/Principal Findings Intravenous administration of paraoxon, but not parathion, caused acute frequency-dependent potentiation of vagally-induced bronchoconstriction and increased electrical field stimulation (EFS)-induced contractions in isolated trachea independent of AChE inhibition. However, paraoxon had no effect on vagally-induced bradycardia in intact guinea pigs or EFS-induced contractions in isolated ileum, suggesting mechanisms other than pharmacologic antagonism of M2 receptors. Paraoxon did not alter M2 receptor expression in cultured cells at the mRNA or protein level as determined by quantitative RT-PCR and radio-ligand binding assays, respectively. Additionally, a biotin-labeled fluorophosphonate, which was used as a probe to identify molecular targets phosphorylated by OPs, did not phosphorylate proteins in guinea pig cardiac membranes that were recognized by M2 receptor antibodies. Conclusions/Significance These data indicate that neither direct pharmacologic antagonism nor downregulated expression of M2 receptors contributes to OP inhibition of M2 function in airway nerves, adding to the growing evidence of non-cholinergic mechanisms of OP neurotoxicity. PMID:20479945

Proskocil, Becky J.; Bruun, Donald A.; Thompson, Charles M.; Fryer, Allison D.; Lein, Pamela J.

2010-01-01

248

Channels active in the excitability of nerves and skeletal muscles across the neuromuscular junction: basic function and pathophysiology  

NSDL National Science Digital Library

Ion channels are essential for the basic physiological function of excitable cells such as nerve, skeletal, cardiac, and smooth muscle cells. Mutations in genes that encode ion channels have been identified to cause various diseases and disorders known as channelopathies. An understanding of how individual ion channels are involved in the activation of motoneurons and their corresponding muscle cells is essential for interpreting basic neurophysiology in nerves, the heart, and skeletal and smooth muscle. This review article is intended to clarify how channels work in nerves, neuromuscular junctions, and muscle function and what happens when these channels are defective. Highlighting the human diseases that result from defective ion channels is likely to be interesting to students in helping them choose to learn about channel physiology.

PhD Barbara E. Goodman (University of South Dakota School of Medicine Division of Basic Biomedical Sciences)

2008-04-11

249

Heterophilic Binding of L1 on Unmyelinated Sensory Axons Mediates Schwann Cell Adhesion and Is Required for Axonal Survival  

Microsoft Academic Search

This study investigated the function of the adhesion molecule L1 in unmyelinated fibers of the pe- ripheral nervous system (PNS) by analysis of L1- deficient mice. We demonstrate that L1 is present on axons and Schwann cells of sensory unmyelinated fi- bers, but only on Schwann cells of sympathetic unmy- elinated fibers. In L1-deficient sensory nerves, Schwann cells formed but

C. A. Haney; Z. Sahenk; C. Li; V. P. Lemmon; J. Roder; B. D. Trapp

1999-01-01

250

Functional ability loss in sensory impaired and sensory unimpaired very old adults: analyzing causal relations with positive affect across four years.  

PubMed

This paper focuses on the relationship between functional ability (FA) and positive affect (PA), a major component of well-being, in sensory impaired very old adults (SI) compared with sensory unimpaired individuals (UI). Previous research mostly suggests a robust causal impact of FA on PA. However, some research, drawing from Fredrickson's broaden-and-build theory, also points to the possibility of an inverse causality between FA and PA. We examine in this paper both of these causal directions in SI as well as UI individuals across a 4year observation period. Additionally, we checked for the role of negative affect (NA). The T1-T2 sample comprised 81 out of 237 SI individuals (visually or hearing impaired) assessed at T1, with a mean age at T1 of 81.8years, and 87 UI individuals out of 150 assessed at T1, with a mean age at T1 of 81.5years. Established scales were used to assess FA, PA, and NA. Using cross-lagged panel analysis to examine the direction of causality, our findings indicate that FA has significant impact on PA in both the SI and the UI group, whereas the alternative causal pathway was not confirmed. Both cross-lagged relationships between FA and NA were non-significant. No group differences in path strengths between SI and UI were present. Our study provides evidence that FA is a key competence for successful emotional aging in vulnerable groups of very old adults such as SI as well as in UI adults in advanced old age. PMID:24929008

Wahl, Hans-Werner; Drapaniotis, Philipp M; Heyl, Vera

2014-11-01

251

[Sacral nerve stimulation in the treatment of the lower urinary tract function disorders].  

PubMed

Functional disorders of the female lower urinary tract like urge incontinence, idiopathic urinary retention and symptoms of urgency-frequency occasionally do not respond properly to classical behavioral and pharmacological therapy Therefore, additional alternative therapies are needed to alleviate these bothersome symptoms. Sacral neuromodulation (SNS) utilize mild electrical pulses which activate or suppress neural reflexes responsible for voiding by stimulating the sacral nerves that innervate the bladder, external urethral sphincter and pelvic floor muscles. The exact mechanism of SNS action is not yet fully understood but it is assumed that it influences the neuroaxis at different levels of the central nervous system and restores the balance between inhibitory and activatory control over the voiding reflex. There is numerous evidence on the success of SNS not only in the treatment of refractory urge incontinence in adult and children but also in idiopathic urinary retention and symptoms of urgency-frequency PMID:22384619

Miot?a, Pawe?; Kulik-Rechberger, Beata; Skorupski, Pawe?; Rechberger, Tomasz

2011-11-01

252

Trapping of organophosphorus chemical nerve agents in water with amino acid functionalized baskets.  

PubMed

We prepared eleven amino-acid functionalized baskets and used (1) H NMR spectroscopy to quantify their affinity for entrapping dimethyl methylphosphonate (DMMP, 118?Å(3) ) in aqueous phosphate buffer at pH=7.0±0.1; note that DMMP guest is akin in size to chemical nerve agent sarin (132?Å(3) ). The binding interaction (Ka ) was found to vary with the size of substituent groups at the basket's rim. In particular, the degree of branching at the first carbon of each substituent had the greatest effect on the host-guest interaction, as described with the Verloop's B1 steric parameter. The branching at the remote carbons, however, did not perturb the encapsulation, which is important for guiding the design of more effective hosts and catalysts in future. PMID:24616086

Ruan, Yian; Dalkiliç, Erdin; Peterson, Paul W; Pandit, Aroh; Dastan, Arif; Brown, Jason D; Polen, Shane M; Hadad, Christopher M; Badji?, Jovica D

2014-04-01

253

Evidence for Glutamate as a Neuroglial Transmitter within Sensory Ganglia  

PubMed Central

This study examines key elements of glutamatergic transmission within sensory ganglia of the rat. We show that the soma of primary sensory neurons release glutamate when depolarized. Using acute dissociated mixed neuronal/glia cultures of dorsal root ganglia (DRG) or trigeminal ganglia and a colorimetric assay, we show that when glutamate uptake by satellite glial cells (SGCs) is inhibited, KCl stimulation leads to simultaneous increase of glutamate in the culture medium. With calcium imaging we see that the soma of primary sensory neurons and SGCs respond to AMPA, NMDA, kainate and mGluR agonists, and selective antagonists block this response. Using whole cell patch-clamp technique, inward currents were recorded from small diameter (<30 µm) DRG neurons from intact DRGs (ex-vivo whole ganglion preparation) in response to local application of the above glutamate receptor agonists. Following a chronic constriction injury (CCI) of either the inferior orbital nerve or the sciatic nerve, glutamate expression increases in the trigeminal ganglia and DRG respectively. This increase occurs in neurons of all diameters and is present in the somata of neurons with injured axons as well as in somata of neighboring uninjured neurons. These data provides additional evidence that glutamate can be released within the sensory ganglion, and that the somata of primary sensory neurons as well as SGCs express functional glutamate receptors at their surface. These findings, together with our previous gene knockdown data, suggest that glutamatergic transmission within the ganglion could impact nociceptive threshold. PMID:23844184

Kung, Ling-Hsuan; Gong, Kerui; Adedoyin, Mary; Ng, Johnson; Bhargava, Aditi; Ohara, Peter T.; Jasmin, Luc

2013-01-01

254

Nerve reconstruction in lumbosacral plexopathy. Case report and review of the literature.  

PubMed

Neurological injury to the lumbosacral plexus associated with pelvic and sacral fractures has traditionally been treated conservatively, despite significant and often debilitating functional deficits of the lower extremities. The authors report a case of reconstruction of the lumbosacral plexus, including nerve grafting to restore lower-extremity function caused by severe trauma to the pelvis. A 16-year-old boy sustained pelvic and sacral fractures in a motor vehicle accident. After stabilization of his orthopedic injuries, he suffered from paresis of his right gluteal and hamstring muscles and had no motor or sensory function below his knee. Two months later, he underwent reconstruction of his lumbosacral plexus performed using a nerve graft from his L-5 and S-1 nerve roots proximal to the inferior gluteal nerve and distal to a branch to the hamstring muscles. After another 2 months, his recovering saphenous nerve was transferred to the sensory component of the posterior tibial nerve by using cabled sural nerve grafts to restore sensation to the sole of his foot. After 2.5 years, he experienced reinnervation of his gluteal and hamstring muscles and could perceive vibration on the sole of his foot. With the assistance of a foot-drop splint, the patient ambulates well and is able to ski. Operative details and the relevant literature are reviewed. PMID:16206740

Tung, Thomas H; Martin, D Zachary; Novak, Christine B; Lauryssen, Carl; Mackinnon, Susan E

2005-01-01

255

Electrical stimulation impairs early functional recovery and accentuates skeletal muscle atrophy after sciatic nerve crush injury in rats.  

PubMed

Neuromuscular recovery after peripheral nerve lesion depends on the regeneration of severed axons that re-establish their functional connection with the denervated muscle. The aim of this study was to determine the effects of electrical stimulation (ES) on the neuromuscular recovery after nerve crush injury in rats. Electrical stimulation was carried out on the tibialis anterior (TA) muscle after sciatic nerve crush injury in a rat model. Six ES sessions were administered every other day starting from day 3 postinjury until the end of the experiment (day 14). The sciatic functional index was calculated. Muscle excitability, neural cell adhesion molecule (N-CAM) expression, and muscle fiber cross-sectional area (CSA) were accessed from TA muscle. Regenerated sciatic nerves were analyzed by light and confocal microscopy. Both treated (crush+ES) and untreated (crush) groups had their muscle weight and CSA decreased compared with the normal group (P < 0.05). Electrical stimulation accentuated muscle fiber atrophy more in the crush+ES than in the crush group (P < 0.05). N-CAM expression increased in both crush and crush+ES groups compared with the normal group (P < 0.05). Regenerated nerves revealed no difference between the crush and crush+ES groups. Nevertheless, functional recovery at day 14 post-injury was significantly lower in crush+ES group compared with the crush group. In addition, the crush+ES group had chronaxie values significantly higher on days 7 and 13 compared with the crush group, which indicates a decrease in muscle excitability in the crush+ES animals. The results of this study do not support a benefit of the tested protocol of ES during the period of motor nerve recovery following injury. PMID:20405500

Gigo-Benato, Davilene; Russo, Thiago Luiz; Geuna, Stefano; Domingues, Natalia Rezende Santa Rosa; Salvini, Tania Fátima; Parizotto, Nivaldo Antonio

2010-05-01

256

Engineering a multimodal nerve conduit for repair of injured peripheral nerve  

NASA Astrophysics Data System (ADS)

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 hydrogel. This indicates return of some feeling to the limb via the fully-configured conduit. Immunohistochemical analysis of the implanted conduits removed from the rats after the four-week implantation period confirmed the presence of myelinated axons within the conduit and distal to the site of implantation, further supporting that the conduit promoted nerve repair over this period of time. This study describes the design considerations and fabrication of a novel multicomponent, multimodal bio-engineered synthetic conduit for peripheral nerve repair.

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

257

Analysis of Graph Invariants in Functional Neocortical Circuitry Reveals Generalized Features Common to Three Areas of Sensory Cortex  

PubMed Central

Correlations in local neocortical spiking activity can provide insight into the underlying organization of cortical microcircuitry. However, identifying structure in patterned multi-neuronal spiking remains a daunting task due to the high dimensionality of the activity. Using two-photon imaging, we monitored spontaneous circuit dynamics in large, densely sampled neuronal populations within slices of mouse primary auditory, somatosensory, and visual cortex. Using the lagged correlation of spiking activity between neurons, we generated functional wiring diagrams to gain insight into the underlying neocortical circuitry. By establishing the presence of graph invariants, which are label-independent characteristics common to all circuit topologies, our study revealed organizational features that generalized across functionally distinct cortical regions. Regardless of sensory area, random and -nearest neighbors null graphs failed to capture the structure of experimentally derived functional circuitry. These null models indicated that despite a bias in the data towards spatially proximal functional connections, functional circuit structure is best described by non-random and occasionally distal connections. Eigenvector centrality, which quantifies the importance of a neuron in the temporal flow of circuit activity, was highly related to feedforwardness in all functional circuits. The number of nodes participating in a functional circuit did not scale with the number of neurons imaged regardless of sensory area, indicating that circuit size is not tied to the sampling of neocortex. Local circuit flow comprehensively covered angular space regardless of the spatial scale that we tested, demonstrating that circuitry itself does not bias activity flow toward pia. Finally, analysis revealed that a minimal numerical sample size of neurons was necessary to capture at least 90 percent of functional circuit topology. These data and analyses indicated that functional circuitry exhibited rules of organization which generalized across three areas of sensory neocortex. PMID:25010654

Gururangan, Suchin S.; Sadovsky, Alexander J.; MacLean, Jason N.

2014-01-01

258

Channels Active in the Excitability of Nerves and Skeletal Muscles across the Neuromuscular Junction: Basic Function and Pathophysiology  

ERIC Educational Resources Information Center

Ion channels are essential for the basic physiological function of excitable cells such as nerve, skeletal, cardiac, and smooth muscle cells. Mutations in genes that encode ion channels have been identified to cause various diseases and disorders known as channelopathies. An understanding of how individual ion channels are involved in the…

Goodman, Barbara E.

2008-01-01

259

[Diagnostics and treatment of acute odontogenic osteomyelitis of the mandible considering functional state of inferior alveolar nerve].  

PubMed

Evaluation of functional impairment of inferior alveolar nerve in acute odontogenic inflammatory processes was carried out in this clinical study by means of stimulation electroneurography. Possibility of early diagnosis of acute odontogenic osteomyelitis by this method and effectiveness of decompression osteoperforation for its treatment was shown. PMID:25016752

Malanchuk, V A; Pavlovski?, L L

2013-01-01

260

Effect of bleaching whey on sensory and functional properties of 80% whey protein concentrate.  

PubMed

Whey is a highly functional food that has found widespread use in a variety of food and beverage applications. A large amount of the whey proteins produced in the United States is derived from annatto-colored Cheddar cheese. Color from annatto is undesirable in whey and must be bleached. The objective of this study was to compare 2 commercially approved bleaching agents, benzoyl peroxide (BP) and hydrogen peroxide (HP), and their effects on the flavor and functionality of 80% whey protein concentrate (WPC80). Colored and uncolored liquid wheys were bleached with BP or HP, and then ultrafiltered, diafiltered, and spray-dried; WPC80 from unbleached colored and uncolored Cheddar whey were manufactured as controls. All treatments were manufactured in triplicate. The WPC80 were then assessed by sensory, instrumental, functionality, color, and proximate analysis techniques. The HP-bleached WPC80 were higher in lipid oxidation compounds (specifically hexanal, heptanal, octanal, nonanal, decanal, dimethyl disulfide, and 1-octen-3-one) and had higher fatty and cardboard flavors compared with the other unbleached and BP-bleached WPC80. The WPC80 bleached with BP had lower norbixin concentrations compared with WPC80 bleached with HP. The WPC powders differed in Hunter color values (L, a, b), with bleached powders being more white, less red, and less yellow than unbleached powders. Bleaching with BP under the conditions used in this study resulted in larger reductions in yellowness of the powders made from whey with annatto color than did bleaching with HP. Functionality testing demonstrated that whey bleached with HP treatments had more soluble protein after 10 min of heating at 90°C at pH 4.6 and pH 7 than the no-bleach and BP treatments, regardless of additional color. Overall, HP bleaching caused more lipid oxidation products and subsequent off-flavors compared with BP bleaching. However, heat stability of WPC80 was enhanced by HP bleaching compared with control or BP-bleached WPC80. PMID:22612922

Jervis, S; Campbell, R; Wojciechowski, K L; Foegeding, E A; Drake, M A; Barbano, D M

2012-06-01

261

Diverse subthreshold cross-modal sensory interactions in the thalamic reticular nucleus: implications for new pathways of cross-modal attentional gating function.  

PubMed

Our attention to a sensory cue of a given modality interferes with attention to a sensory cue of another modality. However, an object emitting various sensory cues attracts attention more effectively. The thalamic reticular nucleus (TRN) could play a pivotal role in such cross-modal modulation of attention given that cross-modal sensory interaction takes place in the TRN, because the TRN occupies a highly strategic position to function in the control of gain and/or gating of sensory processing in the thalamocortical loop. In the present study cross-modal interactions between visual and auditory inputs were examined in single TRN cells of anesthetised rats using juxta-cellular recording and labeling techniques. Visual or auditory responses were modulated by subthreshold sound or light stimuli, respectively, in the majority of recordings (46 of 54 visual and 60 of 73 auditory cells). However, few bimodal sensory cells were found. Cells showing modulation of the sensory response were distributed in the whole visual and auditory sectors of the TRN. Modulated cells sent axonal projections to first-order or higher-order thalamic nuclei. Suppression predominated in modulation that took place not only in primary responses but also in late responses repeatedly evoked after sensory stimulation. Combined sensory stimulation also evoked de-novo responses, and modulated response latency and burst spiking. These results indicate that the TRN incorporates sensory inputs of different modalities into single cell activity to function in sensory processing in the lemniscal and non-lemniscal systems. This raises the possibility that the TRN constitutes neural pathways involved in cross-modal attentional gating. PMID:24646412

Kimura, Akihisa

2014-05-01

262

Functional Role of Diverse Changes in Sympathetic Nerve Activity in Regulating Arterial Pressure during REM Sleep  

PubMed Central

Study Objectives: This study aimed to investigate whether REM sleep evoked diverse changes in sympathetic outflows and, if so, to elucidate why REM sleep evokes diverse changes in sympathetic outflows. Measurements: Male Wistar rats were chronically implanted with electrodes to measure renal (RSNA) and lumbar sympathetic nerve activity (LSNA), electroencephalogram, electromyogram, and electrocardiogram, and catheters to measure systemic arterial and central venous pressure; these parameters were measured simultaneously and continuously during the sleep-awake cycle in the same rat. Results: REM sleep resulted in a step reduction in RNSA by 36.1% ± 2.7% (P < 0.05), while LSNA increased in a step manner by 15.3% ± 2% (P < 0.05) relative to the NREM level. Systemic arterial pressure increased gradually (P < 0.05), while heart rate decreased in a step manner (P < 0.05) during REM sleep. In contrast to REM sleep, RSNA, LSNA, systemic arterial pressure, and heart rate increased in a unidirectional manner associated with increases in physical activity levels in the order from NREM sleep, quiet awake, moving, and grooming state. Thus, the relationship between RSNA vs. LSNA and systemic arterial pressure vs. heart rate observed during REM sleep was dissociated compared with that obtained during the other behavioral states. Conclusions: It is suggested that the diverse changes in sympathetic outflows during REM sleep may be needed to increase systemic arterial pressure by balancing vascular resistance between muscles and vegetative organs without depending on the heart. Citation: Yoshimoto M; Yoshida I; Miki K. Functional role of diverse changes in sympathetic nerve activity in regulating arterial pressure during REM sleep. SLEEP 2011;34(8):1093-1101. PMID:21804671

Yoshimoto, Misa; Yoshida, Ikue; Miki, Kenju

2011-01-01

263

Active compounds and distinctive sensory features provided by American ginseng (Panax quinquefolius L.) extract in a new functional milk beverage.  

PubMed

American ginseng (Panax quinquefolius L.) has recognized neurocognitive effects, and a ginsenoside-rich extract of the root of the plant has been shown to improve cognitive functions in young adults. This study aimed at assessing the chemical and sensory profiles of a UHT-treated, low-lactose functional milk containing American ginseng. Individual ginsenosides in the milk were analyzed by HPLC. Descriptive sensory analysis was performed by a trained panel to quantitatively document sensory changes resulting from the addition of ginseng and the UHT process on flavored and unflavored milks. Consumer acceptance of the product was also investigated. Total ginsenoside content in the UHT-treated milk enriched with the ginseng extract after UHT process treatment was 7.52 mg/100 g of milk, corresponding to a recovery of 67.6% compared with the content in the unprocessed extract. The intake of 150 to 300 mL of this ginseng-enriched milk provides the amount of total ginsenosides (11.5 to 23 mg) necessary to improve cognitive function after its consumption. Both the presence of ginsenosides and their thermal treatment affected some sensory properties of the milk, most notably an increase in bitterness and metallic taste, the appearance of a brownish color, and a decrease in milky flavor. Levels of brown color, bitterness, and metallic taste were highest in the industrially processed ginseng-enriched milk. The bitterness attributable to ginseng extract was reduced by addition of vanilla flavor and sucralose. A consumer exploratory study revealed that a niche of consumers exists who are willing to consume this type of product. PMID:22818438

Tárrega, A; Salvador, A; Meyer, M; Feuillère, N; Ibarra, A; Roller, M; Terroba, D; Madera, C; Iglesias, J R; Echevarría, J; Fiszman, S

2012-08-01

264

Activation of the 5-HT1B/D receptor reduces hindlimb neurogenic inflammation caused by sensory nerve stimulation and capsaicin.  

PubMed

Activation of the 5-HT(1B/D) receptor inhibits cerebrovascular neurogenic inflammation (NI). The aim of this study was to determine if the 5-HT(1B/D) receptor agonist sumatriptan can also inhibit NI in other regions of the body. NI was assessed by measuring plasma extravasation (PE) and changes in blood flow in the rat hindpaw. Sumatriptan was administered locally (20 microl, 50 or 100 nM, s.c.) into the dorso-medial region of one hindpaw. The other paw was pre-treated with vehicle (20 microl of 0.9% saline) and served as a control. NI was induced after treatment with sumatriptan/vehicle by injecting capsaicin (15 microl, 1%, s.c.) into each paw or by electrically stimulating the saphenous nerve (4 Hz, 30s). Sumatriptan administered locally or systemically (300 microg/kg, i.v.) significantly reduced saphenous nerve and capsaicin-induced PE and vasodilation. The systemic and local inhibitory actions of sumatriptan are mediated by the 5-HT(1B/D) receptor as pre-treatment with the 5-HT(1B/D) antagonist GR127935 (GR; 15 microl, 1 microM, s.c. or 0.2 micromol/kg, i.v.) completely blocked the inhibitory effect of sumatriptan on capsaicin-induced vasodilation and reduced the inhibitory effect of sumatriptan on capsaicin and electrically induced-PE. Neither PE induced by local injection of substance P (SP) (20 pmol, 20 microl, s.c.) nor vasodilation induced by local CGRP injection was affected by pre-treatment with sumatriptan. These findings indicate that both local and systemic activation of the 5-HT(1B/D) receptor by sumatriptan reduce NI induced by nerve stimulation or capsaicin presumably by inhibiting neuropeptide release. 5-HT(1B/D) receptor agonists may be useful for the treatment of non-trigeminal pain conditions involving NI. PMID:17499925

Carmichael, Nicole M E; Charlton, Milton P; Dostrovsky, Jonathan O

2008-01-01

265

Differences in autonomic nerve function in patients with silent and symptomatic myocardial ischaemia.  

PubMed Central

BACKGROUND--Autonomic neuropathy provides a mechanism for the absence of symptoms in silent myocardial ischaemia, but characterisation of the type of neuropathy is lacking. AIM--To characterise and compare autonomic nerve function in patients with silent and symptomatic myocardial ischaemia. METHODS AND RESULTS--The Valsalva manoeuvre, heart rate variation (HRV) in response to deep breathing and standing, lower body negative pressure, isometric handgrip, and the cold pressor test were performed by patients with silent (n = 25) and symptomatic (n = 25) ambulatory ischaemia and by controls (n = 21). No difference in parasympathetic efferent function between patients with silent and symptomatic ischaemia was recorded, but both had significantly less HRV in response to standing than the controls (p < 0.005 for silent and p < 0.01 for symptomatic). Patients with silent ischaemia showed an increased propensity for peripheral vasodilatation compared with symptomatic patients (p < 0.02) and controls (p < 0.04). Impaired sympathetic function was found in patients with pure silent ischaemia (n = 4) compared with the remaining patients with silent ischaemia whose pain pathways were presumed to be intact. CONCLUSIONS--Patients with silent ischaemia and pain pathways presumed to be intact have an enhanced peripheral vasodilator response, and if this applied to the coronary vasculature it could provide a mechanism for limiting ischaemia to below the pain threshold. Patients with pure silent ischaemia have evidence of sympathetic autonomic dysfunction. Images PMID:8297687

Shakespeare, C. F.; Katritsis, D.; Crowther, A.; Cooper, I. C.; Coltart, J. D.; Webb-Peploe, M. W.

1994-01-01

266

Stretch-induced nerve injury: a proposed technique for the study of nerve regeneration and evaluation of the influence of gabapentin on this model  

PubMed Central

The rat models currently employed for studies of nerve regeneration present distinct disadvantages. We propose a new technique of stretch-induced nerve injury, used here to evaluate the influence of gabapentin (GBP) on nerve regeneration. Male Wistar rats (300 g; n=36) underwent surgery and exposure of the median nerve in the right forelimbs, either with or without nerve injury. The technique was performed using distal and proximal clamps separated by a distance of 2 cm and a sliding distance of 3 mm. The nerve was compressed and stretched for 5 s until the bands of Fontana disappeared. The animals were evaluated in relation to functional, biochemical and histological parameters. Stretching of the median nerve led to complete loss of motor function up to 12 days after the lesion (P<0.001), compared to non-injured nerves, as assessed in the grasping test. Grasping force in the nerve-injured animals did not return to control values up to 30 days after surgery (P<0.05). Nerve injury also caused an increase in the time of sensory recovery, as well as in the electrical and mechanical stimulation tests. Treatment of the animals with GBP promoted an improvement in the morphometric analysis of median nerve cross-sections compared with the operated vehicle group, as observed in the area of myelinated fibers or connective tissue (P<0.001), in the density of myelinated fibers/mm2 (P<0.05) and in the degeneration fragments (P<0.01). Stretch-induced nerve injury seems to be a simple and relevant model for evaluating nerve regeneration. PMID:24270909

Machado, J.A.; Ghizoni, M.F.; Bertelli, J.; Teske, Gabriel C.; Teske, Guilherme C.; Martins, D.F.; Mazzardo-Martins, L.; Cargnin-Ferreira, E.; Santos, A.R.S.; Piovezan, A.P.

2013-01-01

267

Stretch-induced nerve injury: a proposed technique for the study of nerve regeneration and evaluation of the influence of gabapentin on this model.  

PubMed

The rat models currently employed for studies of nerve regeneration present distinct disadvantages. We propose a new technique of stretch-induced nerve injury, used here to evaluate the influence of gabapentin (GBP) on nerve regeneration. Male Wistar rats (300 g; n=36) underwent surgery and exposure of the median nerve in the right forelimbs, either with or without nerve injury. The technique was performed using distal and proximal clamps separated by a distance of 2 cm and a sliding distance of 3 mm. The nerve was compressed and stretched for 5 s until the bands of Fontana disappeared. The animals were evaluated in relation to functional, biochemical and histological parameters. Stretching of the median nerve led to complete loss of motor function up to 12 days after the lesion (P<0.001), compared to non-injured nerves, as assessed in the grasping test. Grasping force in the nerve-injured animals did not return to control values up to 30 days after surgery (P<0.05). Nerve injury also caused an increase in the time of sensory recovery, as well as in the electrical and mechanical stimulation tests. Treatment of the animals with GBP promoted an improvement in the morphometric analysis of median nerve cross-sections compared with the operated vehicle group, as observed in the area of myelinated fibers or connective tissue (P<0.001), in the density of myelinated fibers/mm2 (P<0.05) and in the degeneration fragments (P<0.01). Stretch-induced nerve injury seems to be a simple and relevant model for evaluating nerve regeneration. PMID:24270909

Machado, J A; Ghizoni, M F; Bertelli, J; Teske, Gabriel C; Teske, Guilherme C; Martins, D F; Mazzardo-Martins, L; Cargnin-Ferreira, E; Santos, A R S; Piovezan, A P

2013-11-01

268

Nerve allografts and conduits in peripheral nerve repair.  

PubMed

Since the last update on nerve conduits and allograft in 2000, investigations have established the efficacy of these alternatives to autograft in the repair of small sensory neural gaps. However, limited insights into the biology of the regenerating nerve continue to preclude intelligent conduit design. Ongoing discoveries in neuroscience and biomaterial engineering hold promise for the eventual development of allograft and conduits with potential of surpassing nerve autografts in clinical efficacy. In this review, we summarize the history, recent advances, and emerging developments in nerve conduits and allograft. PMID:23895714

Lin, Michael Y; Manzano, Givenchy; Gupta, Ranjan

2013-08-01

269

Neuroepithelial circuit formed by innervation of sensory enteroendocrine cells.  

PubMed

Satiety and other core physiological functions are modulated by sensory signals arising from the surface of the gut. Luminal nutrients and bacteria stimulate epithelial biosensors called enteroendocrine cells. Despite being electrically excitable, enteroendocrine cells are generally thought to communicate indirectly with nerves through hormone secretion and not through direct cell-nerve contact. However, we recently uncovered in intestinal enteroendocrine cells a cytoplasmic process that we named neuropod. Here, we determined that neuropods provide a direct connection between enteroendocrine cells and neurons innervating the small intestine and colon. Using cell-specific transgenic mice to study neural circuits, we found that enteroendocrine cells have the necessary elements for neurotransmission, including expression of genes that encode pre-, post-, and transsynaptic proteins. This neuroepithelial circuit was reconstituted in vitro by coculturing single enteroendocrine cells with sensory neurons. We used a monosynaptic rabies virus to define the circuit's functional connectivity in vivo and determined that delivery of this neurotropic virus into the colon lumen resulted in the infection of mucosal nerves through enteroendocrine cells. This neuroepithelial circuit can serve as both a sensory conduit for food and gut microbes to interact with the nervous system and a portal for viruses to enter the enteric and central nervous systems. PMID:25555217

Bohórquez, Diego V; Shahid, Rafiq A; Erdmann, Alan; Kreger, Alex M; Wang, Yu; Calakos, Nicole; Wang, Fan; Liddle, Rodger A

2015-02-01

270

Sensory quality of functional beverages: bitterness perception and bitter masking of olive leaf extract fortified fruit smoothies.  

PubMed

Olive leaf extract (OLE) contains high amounts of oleuropein and hydroxytyrosol. The antioxidant capacity of these polyphenols makes OLE a promising ingredient for functional food. OLE causes very strong bitterness perception and can therefore only be formulated in low concentrations. In this research, bitter detection and recognition thresholds of OLE-fortified fruit smoothies were determined by a trained sensory panel (n = 11). Masking of the OLE's bitter taste was investigated with addition of sodium cyclamate, sodium chloride, and sucrose by means of a standardized ranking method and a scale test. Detection (5.78 mg/100 g) and recognition thresholds (8.05 mg/100 g) of OLE polyphenols confirmed the low formulation limits when bitterness was not masked by other substances. At higher polyphenol levels of 20 mg/100 g, sodium cyclamate and sucrose were able to reduce bitter taste perception by 39.9% and 24.9%, respectively, whereas sodium chloride could not effectively mask bitterness. Practical Application: Development of functional food poses new challenges for the food industry. A major problem in this field is the high bitterness of natural polyphenol-containing extracts with potential health benefits. This research was conducted to understand the sensory impact of olive leaf extract (OLE), a novel food ingredient with very bitter taste. In product development, the data of this research can be considered for formulation limits and the general sensory quality of OLE-fortified food and beverages. PMID:20722953

Kranz, Peter; Braun, Nina; Schulze, Nadine; Kunz, Benno

2010-08-01

271

?2?-1 Gene Deletion Affects Somatosensory Neuron Function and Delays Mechanical Hypersensitivity in Response to Peripheral Nerve Damage  

PubMed Central

The ?2?-1 subunit of voltage-gated calcium channels is upregulated after sensory nerve injury and is also the therapeutic target of gabapentinoid drugs. It is therefore likely to play a key role in the development of neuropathic pain. In this study, we have examined mice in which ?2?-1 gene expression is disrupted, to determine whether ?2?-1 is involved in various modalities of nociception, and for the development of behavioral hypersensitivity after partial sciatic nerve ligation (PSNL). We find that naive ?2?-1?/? mice show a marked behavioral deficit in mechanical and cold sensitivity, but no change in thermal nociception threshold. The lower mechanical sensitivity is mirrored by a reduced in vivo electrophysiological response of dorsal horn wide dynamic range neurons. The CaV2.2 level is reduced in brain and spinal cord synaptosomes from ?2?-1?/? mice, and ?2?-1?/? DRG neurons exhibit lower calcium channel current density. Furthermore, a significantly smaller number of DRG neurons respond to the TRPM8 agonist menthol. After PSNL, ?2?-1?/? mice show delayed mechanical hypersensitivity, which only develops at 11 d after surgery, whereas in wild-type littermates it is maximal at the earliest time point measured (3 d). There is no compensatory upregulation of ?2?-2 or ?2?-3 after PSNL in ?2?-1?/? mice, and other transcripts, including neuropeptide Y and activating transcription factor-3, are upregulated normally. Furthermore, the ability of pregabalin to alleviate mechanical hypersensitivity is lost in PSNL ?2?-1?/? mice. Thus, ?2?-1 is essential for rapid development of mechanical hypersensitivity in a nerve injury model of neuropathic pain. PMID:24133248

Patel, Ryan; Bauer, Claudia S.; Nieto-Rostro, Manuela; Margas, Wojciech; Ferron, Laurent; Chaggar, Kanchan; Crews, Kasumi; Ramirez, Juan D.; Bennett, David L. H.; Schwartz, Arnold; Dickenson, Anthony H.

2013-01-01

272

Biomedical engineering strategies for peripheral nerve repair: surgical applications, state of the art, and future challenges.  

PubMed

Damage to the peripheral nervous system is surprisingly common and occurs primarily from trauma or a complication of surgery. Although recovery of nerve function occurs in many mild injuries, outcomes are often unsatisfactory following severe trauma. Nerve repair and regeneration presents unique clinical challenges and opportunities, and substantial contributions can be made through the informed application of biomedical engineering strategies. This article reviews the clinical presentations and classification of nerve injuries, in addition to the state of the art for surgical decision-making and repair strategies. This discussion presents specific challenges that must be addressed to realistically improve the treatment of nerve injuries and promote widespread recovery. In particular, nerve defects a few centimeters in length use a sensory nerve autograft as the standard technique; however, this approach is limited by the availability of donor nerve and comorbidity associated with additional surgery. Moreover, we currently have an inadequate ability to noninvasively assess the degree of nerve injury and to track axonal regeneration. As a result, wait-and-see surgical decisions can lead to undesirable and less successful "delayed" repair procedures. In this fight for time, degeneration of the distal nerve support structure and target progresses, ultimately blunting complete functional recovery. Thus, the most pressing challenges in peripheral nerve repair include the development of tissue-engineered nerve grafts that match or exceed the performance of autografts, the ability to noninvasively assess nerve damage and track axonal regeneration, and approaches to maintain the efficacy of the distal pathway and targets during the regenerative process. Biomedical engineering strategies can address these issues to substantially contribute at both the basic and applied levels, improving surgical management and functional recovery following severe peripheral nerve injury. PMID:21488817

Pfister, Bryan J; Gordon, Tessa; Loverde, Joseph R; Kochar, Arshneel S; Mackinnon, Susan E; Cullen, D Kacy

2011-01-01

273

A Functional Role for Intra-Axonal Protein Synthesis during Axonal Regeneration from Adult Sensory Neurons  

Microsoft Academic Search

Although intradendritic protein synthesis has been documented in adult neurons, the question of whether axons actively syn- thesize proteins remains controversial. Adult sensory neurons that are conditioned by axonal crush can rapidly extend pro- cesses in vitro by regulating the translation of existing mRNAs (Twiss et al., 2000). These regenerating processes contain ax- onal but not dendritic proteins. Here we

Jun-Qi Zheng; Theresa K. Kelly; Bieshia Chang; Sergey Ryazantsev; Ayyappan K. Rajasekaran; Kelsey C. Martin; Jeffery L. Twiss

2001-01-01

274

The Importance of Sensory Functioning: Guidelines for Infant and Toddler Caregivers  

ERIC Educational Resources Information Center

All children have their own unique ways of interacting with their environments, connecting with people around them, and learning about their world. Babies take in information from their senses and use this information to respond to people and events. Children's daily experiences facilitate integration of their senses. These early sensory

Bagdi, Aparna; Vacca, John; Waninger, Kendra N.

2007-01-01

275

Restoration of visual function following optic nerve regeneration in bluegill (Lepomis macrochirus) x pumpkinseed (Lepomis gibbosus) hybrid sunfish.  

PubMed

Simple (dorsal light reflex) and complex (predator-prey interactions) visually mediated behaviors were used concurrently with morphological examination to assess restoration of visual function following optic nerve crush in bluegill (Lepomis macrochirus) x pumpkinseed (Lepomis gibbosus) hybrid sunfish. Regenerating optic nerve axons projected into the stratum opticum-stratum fibrosum et griseum superficiale by week 2, the stratum griseum centrale by week 4, and stratum album centrale by week 6. Initial projections into the laminae were diffuse and less stratified compared to controls. By week 12, the projection pattern of regenerating nerve fibers closely resembled the innervation of normal tecta. Visual improvements were correlated with increasing projections into the tectum. The dorsal light reflex improved from a 45 degrees vertical deviation following nerve crush to 4.5 degrees by week 16. Initial predator-prey interactions were exclusively mediated by the control eye. As regeneration progressed, there was a gradual expansion of the visual field. The reaction distance and attack angles within the visual field of the experimental eye were initially less than controls, however, these differences disappeared by week 10. Improvements in visual function were closely correlated with an increase of regenerating ganglion cell axons into the optic tectum indicating sufficient synaptogenesis to mediate both simple and complex visual behavior. PMID:17550642

Callahan, Michael P; Mensinger, Allen F

2007-01-01

276

A System for Studying Facial Nerve Function in Rats through Simultaneous Bilateral Monitoring of Eyelid and Whisker Movements  

PubMed Central

The occurrence of inappropriate co-contraction of facially innervated muscles in humans (synkinesis) is a common sequela of facial nerve injury and recovery. We have developed a system for studying facial nerve function and synkinesis in restrained rats using non-contact opto-electronic techniques that enable simultaneous bilateral monitoring of eyelid and whisker movements. Whisking is monitored in high spatio-temporal resolution using laser micrometers, and eyelid movements are detected using infrared diode and phototransistor pairs that respond to the increased reflection when the eyelids cover the cornea. To validate the system, eight rats were tested with multiple five-minute sessions that included corneal air puffs to elicit blink and scented air flows to elicit robust whisking. Four rats then received unilateral facial nerve section and were tested at weeks 3–6. Whisking and eye blink behavior occurred both spontaneously and under stimulus control, with no detectable difference from published whisking data. Proximal facial nerve section caused an immediate ipsilateral loss of whisking and eye blink response, but some ocular closures emerged due to retractor bulbi muscle function. The independence observed between whisker and eyelid control indicates that this system may provide a powerful tool for identifying abnormal co-activation of facial zones resulting from aberrant axonal regeneration. PMID:18442856

Heaton, James T.; Kowaleski, Jeffrey M.; Bermejo, Roberto; Zeigler, H. Philip; Ahlgren, David J.; Hadlock, Tessa A.

2008-01-01

277

Role of sensory experience in functional development of Drosophila motor circuits.  

PubMed

Neuronal circuits are formed according to a genetically predetermined program and then reconstructed in an experience-dependent manner. While the existence of experience-dependent plasticity has been demonstrated for the visual and other sensory systems, it remains unknown whether this is also the case for motor systems. Here we examined the effects of eliminating sensory inputs on the development of peristaltic movements in Drosophila embryos and larvae. The peristalsis is initially slow and uncoordinated, but gradually develops into a mature pattern during late embryonic stages. We tested whether inhibiting the transmission of specific sensory neurons during this period would have lasting effects on the properties of the sensorimotor circuits. We applied Shibire-mediated inhibition for six hours during embryonic development (15-21 h after egg laying [AEL]) and studied its effects on peristalsis in the mature second- and third-instar larvae. We found that inhibition of chordotonal organs, but not multidendritic neurons, led to a lasting decrease in the speed of larval locomotion. To narrow down the sensitive period, we applied shorter inhibition at various embryonic and larval stages and found that two-hour inhibition during 16-20 h AEL, but not at earlier or later stages, was sufficient to cause the effect. These results suggest that neural activity mediated by specific sensory neurons is involved in the maturation of sensorimotor circuits in Drosophila and that there is a critical period for this plastic change. Consistent with a role of chordotonal neurons in sensory feedback, these neurons were activated during larval peristalsis and acute inhibition of their activity decreased the speed of larval locomotion. PMID:23620812

Fushiki, Akira; Kohsaka, Hiroshi; Nose, Akinao

2013-01-01

278

Ultrasonographic evaluation of functioning free muscle transfer: comparison between spinal accessory and intercostal nerve reinnervation.  

PubMed

This study focuses on the application of ultrasonography as a means of measuring the cross-sectional area (CSA) of the transferred muscle and evaluating its force recovery following functioning free muscle transfer. The objective of the study was to compare the CSA of a transferred muscle that is either reinnervated by the spinal accessory nerve (SAN) or the intercostal nerve (ICN), and to evaluate the difference in their force recovery. Ten patients with complete avulsion of the brachial plexus who underwent a double free muscle technique for restoring prehensile function were evaluated. All patients were followed up for at least 1.5 years after the operation. The CSAs of 20 transferred gracilis muscles in 10 patients, reinnervated either by SAN or ICN, were measured by ultrasonography. The CSA was measured at relaxation and at maximal isometric contraction. The force recovery of each muscle was expressed as the contraction rate (CR), calculated by dividing the CSA of the muscle in maximum isometric contraction by the CSA of the muscle in relaxation. The mean CSA of the transferred muscles reinnervated by the SAN was 2.98 +/- 0.723 cm (2) in relaxation and 3.95 +/- 1.296 cm (2) in maximum isometric contraction; thereby a CR of 1.32 +/- 0.174 was obtained. The mean CSA of the transferred muscles reinnervated by the ICN was 2.32 +/- 0.520 cm (2) and 2.69 +/- 0.566 cm (2) in relaxation and maximal isometric contraction, respectively; thus a CR of 1.16 +/- 0.068 was obtained. Results showed that the CR was significantly higher among the transferred muscles reinnervated by the SAN than those by the ICN. This study demonstrated that muscles that are reinnervated by the SAN resulted in stronger recovery than those reinnervated by the ICN, and that ultrasonography has the capacity to evaluate force recovery of each muscle by measuring the CSA during the two phases of muscle activity. PMID:16894486

Hattori, Yasunori; Doi, Kazutera; Ikedu, Keisuke; Kodama, Narihito; Pagsaligan, Jose Miguel

2006-08-01

279

Effects of a serotonin 5-HT4 receptor antagonist SB-207266 on gastrointestinal motor and sensory function in humans  

PubMed Central

BACKGROUND—Serotonin 5-HT4 receptors are located on enteric cholinergic neurones and may regulate peristalsis. 5-HT4 receptors on primary afferent neurones have been postulated to modulate visceral sensation. While 5-HT4 agonists are used as prokinetic agents, the physiological role of 5-HT4 receptors in the human gut is unknown.?AIMS—Our aim was to characterise the role of 5-HT4 receptors in regulating gastrointestinal motor and sensory function in healthy subjects under baseline and stimulated conditions with a 5-HT4 receptor antagonist.?METHODS—Part A compared the effects of placebo to four doses of a 5-HT4 receptor antagonist (SB-207266) on the cisapride mediated increase in plasma aldosterone (a 5-HT4 mediated response) and orocaecal transit in 18 subjects. In part B, 52 healthy subjects received placebo, or 0.05, 0.5, or 5 mg of SB-207266 for 10-12 days; gastric, small bowel, and colonic transit were measured by scintigraphy on days 7-9, and fasting and postprandial colonic motor function, compliance, and sensation during distensions were assessed on day 12.?RESULTS—Part A: 0.5, 5, and 20 mg doses of SB-207266 had significant and quantitatively similar effects, antagonising the cisapride mediated increase in plasma aldosterone and acceleration of orocaecal transit. Part B: SB-207266 tended to delay colonic transit (geometric centre of isotope at 24 (p=0.06) and 48 hours (p=0.08)), but did not have dose related effects on transit, fasting or postprandial colonic motor activity, compliance, or sensation.?CONCLUSION—5-HT4 receptors are involved in the regulation of cisapride stimulated orocaecal transit; SB 207266 tends to modulate colonic transit but not sensory functions or compliance in healthy human subjects.???Keywords: 5-HT4 receptors; colon transit; gastrointestinal motor function; gastrointestinal sensory function PMID:11034583

Bharucha, A; Camilleri, M; Haydock, S; Ferber, I; Burton, D; Cooper, S; Tompson, D; Fitzpatrick, K; Higgins, R; Zinsmeister, A

2000-01-01

280

Functionalized gold nanoparticle supported sensory mechanisms applied in detection of chemical and biological threat agents: a review.  

PubMed

There is a great necessity for development of novel sensory concepts supportive of smart sensing capabilities in defense and homeland security applications for detection of chemical and biological threat agents. A smart sensor is a detection device that can exhibit important features such as speed, sensitivity, selectivity, portability, and more importantly, simplicity in identifying a target analyte. Emerging nanomaterial based sensors, particularly those developed by utilizing functionalized gold nanoparticles (GNPs) as a sensing component potentially offer many desirable features needed for threat agent detection. The sensitiveness of physical properties expressed by GNPs, e.g. color, surface plasmon resonance, electrical conductivity and binding affinity are significantly enhanced when they are subjected to functionalization with an appropriate metal, organic or biomolecular functional groups. This sensitive nature of functionalized GNPs can be potentially exploited in the design of threat agent detection devices with smart sensing capabilities. In the presence of a target analyte (i.e., a chemical or biological threat agent) a change proportional to concentration of the analyte is observed, which can be measured either by colorimetric, fluorimetric, electrochemical or spectroscopic means. This article provides a review of how functionally modified gold colloids are applied in the detection of a broad range of threat agents, including radioactive substances, explosive compounds, chemical warfare agents, biotoxins, and biothreat pathogens through any of the four sensory means mentioned previously. PMID:22244163

Upadhyayula, Venkata K K

2012-02-17

281

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

SciTech Connect

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 {beta} 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.

Wang Junru [Department of Surgery, University of Arkansas for Medical Sciences and Central Arkansas Veterans Healthcare System, Little Rock, AR (United States); Zheng Huaien [Department of Surgery, University of Arkansas for Medical Sciences and Central Arkansas Veterans Healthcare System, Little Rock, AR (United States); Kulkarni, Ashwini [Department of Surgery, University of Arkansas for Medical Sciences and Central Arkansas Veterans Healthcare System, Little Rock, AR (United States); Ou Xuemei [Department of Surgery, University of Arkansas for Medical Sciences and Central Arkansas Veterans Healthcare System, Little Rock, AR (United States); Hauer-Jensen, Martin [Department of Surgery, University of Arkansas for Medical Sciences and Central Arkansas Veterans Healthcare System, Little Rock, AR (United States) and Department of Pathology, University of Arkansas for Medical Sciences and Central Arkansas Veterans Healthcare System, Little Rock, AR (United States)]. E-mail: mhjensen@life.uams.edu

2006-04-01

282

Acetyl l-carnitine corrects the altered peripheral nerve function of experimental diabetes  

Microsoft Academic Search

Acetyl-l-carnitine (ALC) has been shown to facilitate the repair of transected sciatic nerves. The effect of ALC (50 mg\\/kg\\/d) on the diminished nerve conduction velocity (NCV) of rats with streptozotocin (STZ)-induced hyperglycemia of 3 weeks' duration was evaluated. The aldose reductase inhibitor, sorbinil, which is reported to normalize the impaired NCV associated with experimental diabetes, was used as a positive

S. Lowitt; J. I. Malone; A. F. Salem; J. Korthals; S. Benford

1995-01-01

283

Muscle-specific function of the centronuclear myopathy and Charcot-Marie-Tooth neuropathy-associated dynamin 2 is required for proper lipid metabolism, mitochondria, muscle fibers, neuromuscular junctions and peripheral nerves.  

PubMed

The ubiquitously expressed large GTPase Dynamin 2 (DNM2) plays a critical role in the regulation of intracellular membrane trafficking through its crucial function in membrane fission, particularly in endocytosis. Autosomal-dominant mutations in DNM2 cause tissue-specific human disorders. Different sets of DNM2 mutations are linked to dominant intermediate Charcot-Marie-Tooth neuropathy type B, a motor and sensory neuropathy affecting primarily peripheral nerves, or autosomal-dominant centronuclear myopathy (CNM) presenting with primary damage in skeletal muscles. To understand the underlying disease mechanisms, it is imperative to determine to which degree the primary affected cell types require DNM2. Thus, we used cell type-specific gene ablation to examine the consequences of DNM2 loss in skeletal muscle cells, the major relevant cell type involved in CNM. We found that DNM2 function in skeletal muscle is required for proper mouse development. Skeletal muscle-specific loss of DNM2 causes a reduction in muscle mass and in the numbers of muscle fibers, altered muscle fiber size distributions, irregular neuromuscular junctions (NMJs) and isolated degenerating intramuscular peripheral nerve fibers. Intriguingly, a lack of muscle-expressed DNM2 triggers an increase of lipid droplets (LDs) and mitochondrial defects. We conclude that loss of DNM2 function in skeletal muscles initiates a chain of harmful parallel and serial events, involving dysregulation of LDs and mitochondrial defects within altered muscle fibers, defective NMJs and peripheral nerve degeneration. These findings provide the essential basis for further studies on DNM2 function and malfunction in skeletal muscles in health and disease, potentially including metabolic diseases such as diabetes. PMID:23813975

Tinelli, Elisa; Pereira, Jorge A; Suter, Ueli

2013-11-01

284

Neurogenesis of Retinal Ganglion Cells Is Not Essential to Visual Functional Recovery after Optic Nerve Injury in Adult Zebrafish  

PubMed Central

Zebrafish central nervous system (CNS) possesses a strong neural regeneration ability to restore visual function completely after optic nerve injury (ONI). However, whether neurogenesis of retinal ganglion cell (RGC) contributes to functional recovery remains controversial. Our quantitative analysis of RGCs in different ONI models showed that almost all RGCs survived in optic nerve crush (ONC) model; while over 90% of RGCs survived in the first 2 weeks with 75% remaining after 7 weeks in optic nerve transection (ONT) model. Retrograde labeling from tectum revealed a surprising regeneration rate, with over 90% and over 50% of RGCs regrowing axons to tectum at the first week in ONC and ONT model respectively. In the latter one, the number of regenerative RGCs after 4 weeks had no significant difference from the control group. As for neurogenesis, newborn RGCs were rarely detected either by double retrograde labeling or BrdU marker. Since few RGCs died, microglia number showed a temporary increase at 3 days post injury (dpi) and a decrease at 14 dpi. Finally, myelin structure within retina kept integrity and optomotor response (OMR) test demonstrated visual functional restoration at 5 weeks post injury (wpi). In conclusion, our results have directly shown that RGC survival and axon regrowth are responsible for functional recovery after ONI in adult zebrafish. PMID:23437359

Zou, Suqi; Tian, Chen; Ge, Shuchao; Hu, Bing

2013-01-01

285

The Endocranial Anatomy of Therizinosauria and Its Implications for Sensory and Cognitive Function  

PubMed Central

Background Therizinosauria is one of the most enigmatic and peculiar clades among theropod dinosaurs, exhibiting an unusual suite of characters, such as lanceolate teeth, a rostral rhamphotheca, long manual claws, and a wide, opisthopubic pelvis. This specialized anatomy has been associated with a shift in dietary preferences and an adaptation to herbivory. Despite a large number of discoveries in recent years, the fossil record for Therizinosauria is still relatively poor, and cranial remains are particularly rare. Methodology/Principal Findings Based on computed tomographic (CT) scanning of the nearly complete and articulated skull of Erlikosaurus andrewsi, as well as partial braincases of two other therizinosaurian taxa, the endocranial anatomy is reconstructed and described. The wider phylogenetic range of the described specimens permits the evaluation of sensory and cognitive capabilities of Therizinosauria in an evolutionary context. The endocranial anatomy reveals a mosaic of plesiomorphic and derived characters in therizinosaurians. The anatomy of the olfactory apparatus and the endosseous labyrinth suggests that olfaction, hearing, and equilibrium were well-developed in therizinosaurians and might have affected or benefited from an enlarged telencephalon. Conclusion/Significance This study presents the first appraisal of the evolution of endocranial anatomy and sensory adaptations in Therizinosauria. Despite their phylogenetically basal position among maniraptoran dinosaurs, therizinosaurians had developed the neural pathways for a well developed sensory repertoire. In particular olfaction and hearing may have played an important role in foraging, predator evasion, and/or social complexity. PMID:23284972

Lautenschlager, Stephan; Rayfield, Emily J.; Altangerel, Perle; Zanno, Lindsay E.; Witmer, Lawrence M.

2012-01-01

286

Vagal Nerve Stimulation Reverses Aberrant Dopamine System Function in the Methylazoxymethanol Acetate Rodent Model of Schizophrenia  

PubMed Central

Vagal nerve stimulation (VNS) is an alternative therapy for epilepsy and treatment refractory depression. Here we examine VNS as a potential therapy for the treatment of schizophrenia in the methylozoxymethanol acetate (MAM) rodent model of the disease. We have previously demonstrated that hyperactivity within ventral regions of the hippocampus (vHipp) drives the dopamine system dysregulation in this model. Moreover, by targeting the vHipp directly, we can reverse aberrant dopamine system function and associated behaviors in the MAM model. Although the central effects of VNS have not been completely delineated, positron emission topographic measurements of cerebral blood flow in humans have consistently reported that VNS stimulation induces bilateral decreases in hippocampal activity. Based on our previous observations, we performed in vivo extracellular electrophysiological recordings in MAM- and saline-treated rats to evaluate the effect of chronic (2 week) VNS treatment on the activity of putative vHipp pyramidal neurons, as well as downstream dopamine neuron activity in the ventral tegmental area. Here we demonstrate that chronic VNS was able to reverse both vHipp hyperactivity and aberrant mesolimbic dopamine neuron function in the MAM model of schizophrenia. Additionally, VNS reversed a behavioral correlate of the positive symptoms of schizophrenia. Because current therapies for schizophrenia are far from adequate, with a large number of patients discontinuing treatment due to low efficacy or intolerable side effects, it is important to explore alternative nonpharmacological treatments. These data provide the first preclinical evidence that VNS may be a possible alternative therapeutic approach for the treatment of schizophrenia. PMID:25009259

Perez, Stephanie M.; Carreno, Flavia R.; Frazer, Alan

2014-01-01

287

Laminin-based Nanomaterials for Peripheral Nerve Tissue Engineering  

NASA Astrophysics Data System (ADS)

Peripheral nerve transection occurs commonly in traumatic injury, causing motor and sensory deficits distal to the site of injury. One option for surgical repair is the nerve conduit. Conduits currently on the market are hollow tubes into which the nerve ends are sutured. Although these conduits fill the gap, they often fail due to the slow rate of regeneration over long gaps. To facilitate increased speed of regeneration and greater potential for functional recovery, the ideal conduit should provide biochemically relevant signals and physical guidance cues, thus playing an active role in peripheral nerve regeneration. In this dissertation, I fabricated laminin-1 and laminin-polycaprolactone (PCL) blend nanofibers that mimic the geometry and functionality of the peripheral nerve basement membrane. These fibers resist hydration in aqueous media and require no harsh chemical crosslinkers. Adhesion and differentiation of both neuron-like and neuroprogenitor cells is improved on laminin nanofibrous meshes over two-dimensional laminin substrates. Blend meshes with varying laminin content were characterized for composition, tensile properties, degradation rates, and bioactivity in terms of cell attachment and axonal elongation. I have established that 10% (wt) laminin content is sufficient to retain the significant neurite-promoting effects of laminin critical in peripheral nerve repair. In addition, I utilized modified collector plate design to manipulate electric field gradients during electrospinning for the fabrication of aligned nanofibers. These aligned substrates provide enhanced directional guidance cues to the regenerating axons. Finally, I replicated the clinical problem of peripheral nerve transection using a rat tibial nerve defect model for conduit implantation. When the lumens of conduits were filled with nanofiber meshes of varying laminin content and alignment, I observed significant recovery of sensory and motor function over six weeks. This recovery was supported by nerve conduction studies and electromyography which described impulse transmission, muscle stimulation, and foot twitch through the region of regeneration. These studies provide a firm foundation for the use of natural-synthetic blend electrospun nanofibers to enhance existing hollow nerve guidance conduits. The similarity in surgical technique and obvious benefit to the patient should lead to rapid translation into clinical application.

Neal, Rebekah Anne

288

Human sensory subsystems emulator.  

PubMed

Last year this author presented his design for a computerized human nervous system function emulator for use in an android robot. This paper describes that emulator's sensory subsystems in more detail and adds new functions. Topics covered include sensor types, signal conditioning, data handling in the afferent pathways and interpretation of sensory information. Physiological sensory modalities (including: temperature, pressure, acceleration, humidity, sound and light stimuli) as well as nonphysiological (including: magnetic, radio, infrared, ultrasound and satellite GPS) are elucidated. The relationship of a primitive stimulus (i.e.: heat) to a high level sensation (i.e.: pain) is explored. PMID:11347421

Frenger, P

2001-01-01

289

Lower cranial nerves function after surgical treatment of Fisch Class C and D tympanojugular paragangliomas.  

PubMed

The aim of this study was to report the postoperative lower cranial nerves (LCNs) function in patients undergoing surgery for tympanojugular paraganglioma (TJP) and to evaluate risk factors for postoperative LCN dysfunction. A retrospective case review of 122 patients having Fisch class C or D TJP, surgically treated from 1988 to 2012, was performed. The follow-up of the series ranged from 12 to 156 months (mean, 39.4 ± 32.6 months). The infratemporal type A approach was the most common surgical procedure. Gross total tumor removal was achieved in 86 % of cases. Seventy-two percent of the 54 patients with preoperative LCN deficit had intracranial tumor extension. Intraoperatively, LCNs had to be sacrificed in 63 cases (51.6 %) due to tumor infiltration. Sixty-six patients (54.09 %) developed a new deficit of one or more of the LCNs. Of those patients who developed new LCN deficits, 23 of them had intradural extension. Postoperative follow-up of at least 1 year showed that the LCN most commonly affected was the CN IX (50 %). Logistic regression analysis showed that intracranial transdural tumor extension was correlated with the higher risk of LCN sacrifice (p < 0.05). Despite the advances in skull base surgery, new postoperative LCN deficits still represent a challenge. The morbidity associated with resection of the LCNs is dependent on the tumor's size and intradural tumor extension. Though no recovery of LCN deficits may be expected, on long-term follow-up, patients usually compensate well for their LCNs loss. PMID:24327081

Bacciu, Andrea; Medina, Marimar; Ait Mimoune, Hassen; D'Orazio, Flavia; Pasanisi, Enrico; Peretti, Giorgio; Sanna, Mario

2015-02-01

290

Use of axonal projection patterns for the homologisation of cerebral nerves in Opisthobranchia, Mollusca and Gastropoda  

PubMed Central

Introduction Gastropoda are guided by several sensory organs in the head region, referred to as cephalic sensory organs (CSOs). These CSOs are innervated by distinct nerves. This study proposes a unified terminology for the cerebral nerves and the categories of CSOs and then investigates the neuroanatomy and cellular innervation patterns of these cerebral nerves, in order to homologise them. The homologisation of the cerebral nerves in conjunction with other data, e.g. ontogenetic development or functional morphology, may then provide insights into the homology of the CSOs themselves. Results Nickel-lysine axonal tracing (“backfilling”) was used to stain the somata projecting into specific nerves in representatives of opisthobranch Gastropoda. Tracing patterns revealed the occurrence, size and relative position of somata and their axons and enabled these somata to be mapped to specific cell clusters. Assignment of cells to clusters followed a conservative approach based primarily on relative location of the cells. Each of the four investigated cerebral nerves could be uniquely identified due to a characteristic set of soma clusters projecting into the respective nerves via their axonal pathways. Conclusions As the described tracing patterns are highly conserved morphological characters, they can be used to homologise nerves within the investigated group of gastropods. The combination of adequate number of replicates and a comparative approach allows us to provide preliminary hypotheses on homologies for the cerebral nerves. Based on the hypotheses regarding cerebral nerve homology together with further data on ultrastructure and immunohistochemistry of CSOs published elsewhere, we can propose preliminary hypotheses regarding homology for the CSOs of the Opisthobranchia themselves. PMID:23597272

2013-01-01

291

Large-Scale Functional Reorganization in Adult Monkey Cortex after Peripheral Nerve Injury  

NASA Astrophysics Data System (ADS)

In adult monkeys, peripheral nerve injuries induce dramatic examples of neural plasticity in somatosensory cortex. It has been suggested that a cortical distance limit exists and that the amount of plasticity that is possible after injury is constrained by this limit. We have investigated this possibility by depriving a relatively large expanse of cortex by transecting and ligating both the median and the ulnar nerves to the hand. Electrophysiological recording in cortical areas 3b and 1 in three adult squirrel monkeys no less than 2 months after nerve transection has revealed that cutaneous responsiveness is regained throughout the deprived cortex and that a roughly normal topographic order is reestablished for the reorganized cortex.

Garraghty, Preston E.; Kaas, Jon H.

1991-08-01

292

Pharmacological enhancement of peripheral nerve regeneration in the rat by systemic acetyl- L-carnitine treatment  

Microsoft Academic Search

Peripheral nerve trauma remains a major cause of morbidity, largely due to the death of ?40% of innervating sensory neurons, and to slow regeneration after repair. Acetyl-L-carnitine (ALCAR) is a physiological peptide that virtually eliminates sensory neuronal death, and may improve regeneration after primary nerve repair. This study determines the effect of ALCAR upon regeneration after secondary nerve repair, thereby

Andrew McKay Hart; Mikael Wiberg; Giorgio Terenghi

2002-01-01

293

Rapid development of Purkinje cell excitability, functional cerebellar circuit, and afferent sensory input to cerebellum in zebrafish  

PubMed Central

The zebrafish has significant advantages for studying the morphological development of the brain. However, little is known about the functional development of the zebrafish brain. We used patch clamp electrophysiology in live animals to investigate the emergence of excitability in cerebellar Purkinje cells, functional maturation of the cerebellar circuit, and establishment of sensory input to the cerebellum. Purkinje cells are born at 3 days post-fertilization (dpf). By 4 dpf, Purkinje cells spontaneously fired action potentials in an irregular pattern. By 5 dpf, the frequency and regularity of tonic firing had increased significantly and most cells fired complex spikes in response to climbing fiber activation. Our data suggest that, as in mammals, Purkinje cells are initially innervated by multiple climbing fibers that are winnowed to a single input. To probe the development of functional sensory input to the cerebellum, we investigated the response of Purkinje cells to a visual stimulus consisting of a rapid change in light intensity. At 4 dpf, sudden darkness increased the rate of tonic firing, suggesting that afferent pathways carrying visual information are already active by this stage. By 5 dpf, visual stimuli also activated climbing fibers, increasing the frequency of complex spiking. Our results indicate that the electrical properties of zebrafish and mammalian Purkinje cells are highly conserved and suggest that the same ion channels, Nav1.6 and Kv3.3, underlie spontaneous pacemaking activity. Interestingly, functional development of the cerebellum is temporally correlated with the emergence of complex, visually-guided behaviors such as prey capture. Because of the rapid formation of an electrically-active cerebellum, optical transparency, and ease of genetic manipulation, the zebrafish has great potential for functionally mapping cerebellar afferent and efferent pathways and for investigating cerebellar control of motor behavior. PMID:25565973

Hsieh, Jui-Yi; Ulrich, Brittany; Issa, Fadi A.; Wan, Jijun; Papazian, Diane M.

2014-01-01

294

Peripheral nerve conduits: technology update  

PubMed Central

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

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

2014-01-01

295

Analysis and Measurement of the Sympathetic and Sensory Innervation of White and Brown Adipose Tissue  

PubMed Central

Here, we provide a detailed account of how to denervate white and brown adipose tissue (WAT and BAT) and how to measure sympathetic nervous system (SNS) activity to these and other tissues neurochemically. The brain controls many of the functions of WAT and BAT via the SNS innervation of the tissues, especially lipolysis and thermogenesis, respectively. There is no clearly demonstrated parasympathetic innervation of WAT or the major interscapular BAT (IBAT) depot. WAT and BAT communicate with the brain neurally via sensory nerves. We detail the surgical denervation (eliminating both innervations) of several WAT pads and IBAT. We also detail more selective chemical denervation of the SNS innervation via intra-WAT/IBAT 6-hydroxy-dopamine (a catecholaminergic neurotoxin) injections and selective chemical sensory denervation via intra-WAT/IBAT capsaicin (a sensory nerve neurotoxin) injections. Verifications of the denervations are provided (HPLC-EC detection for SNS, ELIA for calcitonin gene-related peptide (proven sensory nerve marker)). Finally, assessment of the SNS drive to WAT/BAT or other tissues is described using the alpha-methyl-para-tyrosine method combined with HPLC-EC, a direct neurochemical measure of SNS activity. These methods have proven useful for us and for other investigators interested in innervation of adipose tissues. The chemical denervation approach has been extended to nonadipose tissues as well. PMID:24480348

Vaughan, Cheryl H.; Zarebidaki, Eleen; Ehlen, J. Christopher; Bartness, Timothy J.

2014-01-01

296

Somatomotor and sensory urethral control of micturition in female rats.  

PubMed

In rats, axons of external urethral sphincter (EUS) motoneurons travel through the anastomotic branch of the pudendal nerve (ABPD) and anastomotic branch of the lumbosacral trunk (ABLT) and converge in the motor branch of the sacral plexus (MBSP). The aim of the present study was to determine in female rats the contribution of these somatomotor pathways and urethral sensory innervation from the dorsal nerve of the clitoris on urinary continence and voiding. EUS electromyographic (EMG) activity during cystometry, leak point pressure (LPP), and voiding efficiency (VE) were assessed in anesthetized virgin Sprague-Dawley female rats before and after transection of the above nerve branches. Transection of the MBSP eliminated EUS EMG, decreased LPP by 50%, and significantly reduced bladder contraction duration, peak pressure, intercontraction interval, and VE. Transection of the ABPD or ABLT decreased EUS EMG discharge and LPP by 25% but did not affect VE. Transection of the dorsal nerve of the clitoris did not affect LPP but reduced contraction duration, peak pressure, intercontraction interval, and VE. We conclude that somatomotor control of micturition is provided by the MBSP with axons travelling through the ABPD and ABLT. Partial somatomotor urethral denervation induces mild urinary incontinence, whereas partial afferent denervation induces voiding dysfunction. ABPD and ABLT pathways could represent a safeguard ensuring innervation to the EUS in case of upper nerve damage. Detailed knowledge of neuroanatomy and functional innervation of the urethra will enable more accurate animal models of neural development, disease, and dysfunction in the future. PMID:25339694

Cruz, Yolanda; Pastelín, César; Balog, Brian M; Zaszczurynski, Paul J; Damaser, Margot S

2014-12-01

297

Nerve conduction studies in early tuberculoid leprosy  

PubMed Central

Context: Hansen's disease is a chronic illness; besides involving skin and peripheral nerves, it affects multiple organs. Nerve involvement is always present in leprosy, and it may be present much before the patient manifests clinically. Aims: To assess nerve conduction parameters in thickened and contralateral non-thickened nerves in early tuberculoid leprosy Materials and Methods: Fifty new untreated male patients with tuberculoid and borderline tuberculoid leprosy in the age group of 15-50 years with thickened peripheral nerves on one side were included in the study. Nerve conduction studies consisting of sensory and motor velocity (NCV), distal latencies, and amplitude were carried out on thickened ulnar, common peroneal, and posterior tibial nerves and contralateral normal nerves. Statistical Analysis Used: Mean values along with coefficient of variation were obtained for various parameters. These were compared with normal values of the control population. P value was used to verify statistical significance. Results: Nerve conduction parameters were deranged in most of the thickened nerves. Sensory parameters were affected early in the disease process. Conclusion: Additional parameters are required to assess nerve damage in early cases, where it is more in slow conducting fibers (average velocity fibers). Change in conduction velocity may not be marked; this calls for the measurement of fast fibers separately because potentials recorded are mainly from myelinated fibers. PMID:25593812

Vashisht, Deepak; Das, Arjun Lal; Vaishampayan, Sanjeev S; Vashisht, Surbhi; Joshi, Rajneesh

2014-01-01

298

Electro-acupuncture promotes differentiation of mesenchymal stem cells, regeneration of nerve fibers and partial functional recovery after spinal cord injury  

Microsoft Academic Search

In order to improve the structure and function of acute spinal cord injury, the present study investigated the effect of electro-acupuncture (EA) on the differentiation of mesenchymal stem cells (MSCs) and the regeneration of nerve fibers in transected spinal cord of rats. The differentiation of MSCs into neuron-like cells and neuroglial cells and regeneraton of 5-hydroxytrptamine (HT) nerve fibers in

Qing Yan; Jing-wen Ruan; Ying Ding; Wen-jie Li; Yan Li; Yuan-shan Zeng

2011-01-01

299

Repair of sciatic nerve defects using tissue engineered nerves  

PubMed Central

In this study, we constructed tissue-engineered nerves with acellular nerve allografts in Sprague-Dawley rats, which were prepared using chemical detergents-enzymatic digestion and mechanical methods, in combination with bone marrow mesenchymal stem cells of Wistar rats cultured in vitro, to repair 15 mm sciatic bone defects in Wistar rats. At postoperative 12 weeks, electrophysiological detection results showed that the conduction velocity of regenerated nerve after repair with tissue-engineered nerves was similar to that after autologous nerve grafting, and was higher than that after repair with acellular nerve allografts. Immunohistochemical staining revealed that motor endplates with acetylcholinesterase-positive nerve fibers were orderly arranged in the middle and superior parts of the gastrocnemius muscle; regenerated nerve tracts and sprouted branches were connected with motor endplates, as shown by acetylcholinesterase histochemistry combined with silver staining. The wet weight ratio of the tibialis anterior muscle at the affected contralateral hind limb was similar to the sciatic nerve after repair with autologous nerve grafts, and higher than that after repair with acellular nerve allografts. The hind limb motor function at the affected side was significantly improved, indicating that acellular nerve allografts combined with bone marrow mesenchymal stem cell bridging could promote functional recovery of rats with sciatic nerve defects. PMID:25206507

Zhang, Caishun; Lv, Gang

2013-01-01

300

Neurotrophin3 Administration Attenuates Deficits of Pyridoxine-Induced Large-Fiber Sensory Neuropathy  

Microsoft Academic Search

Chronic treatment of adult rats for 2-3 weeks with high doses of pyridoxine (vitamin B6) produced a profound proprioceptive loss, similar to that found in humans overdosed with this vita- min or treated with the chemotherapeutic agent cisplatin. Pyr- idoxine toxicity was manifest as deficits in simple and precise locomotion and sensory nerve function and as degeneration of large-diameter\\/large-fiber spinal

Maureen E. Helgren; Kenneth D. Cliffer; Kim Torrento; Chris Cavnor; Rory Curtis; Peter S. DiStefano; Stanley J. Wiegand; Ronald M. Lindsay

1997-01-01

301

Biofabrication and testing of a fully cellular nerve graft.  

PubMed

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. PMID:24192236

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

2013-12-01

302

Quality and sensory acceptability of a chilled functional apple ready-dessert.  

PubMed

An apple and dairy based ready-dessert with an added prebiotic was stored and chill temperatures and number of quality attributes were monitored during chill (4?°C) storage for 30 days. All ready-desserts were thermally processed by sous vide (P (90)?>?10 min). The stability of the dairy component in ready-desserts was monitored by measuring volatile free fatty acids. Changes in these components were more evident in prebiotic-enriched samples compared to controls. However, no significant differences were observed over storage in control and prebiotic-enriched ready-desserts. This was supported by sensory analysis that showed no significant changes over storage in control or prebiotic-enriched samples. Of the other quality parameters, the addition of prebiotic inclusions resulted in lower L and b values and dry matter (p?

Keenan, D F; Brunton, N P; Gormley, T R; Butler, F

2012-04-01

303

The need for assessment of sensory functioning in ageing people with mental handicap.  

PubMed

Within the framework of a study on the ageing process of people with mental handicap in the Netherlands, information about visual and hearing impairments in 1583 people with mental handicap living in group homes or institutions was obtained from their physicians by means of a written questionnaire. Of the people with Down's syndrome (DS) who were older than 50 years of age, 46% had a visual impairment, whereas approximately 13% of subjects with other causes of mental handicap at the same age experienced similar visual impairment. Hearing loss in this age group was reported in 28% of people with DS, but only in 8% of subjects with other causes of mental handicap. The most common eye condition was cataracts, and the most frequent cause of hearing impairment was infection. In people with severe and profound mental handicap of all ages, sensory impairments were more frequent than in persons with mild or moderate mental handicap. Glasses or hearing aids were rarely used by people with severe or profound mental handicap. Assessment of visual and hearing impairments in people with mental handicap seemed clearly indicated, especially in those aged 50 years and older, in those with DS, and in those with severe or profound mental handicap. PMID:8061474

van Schrojenstein Lantman-de Valk, H M; Haveman, M J; Maaskant, M A; Kessels, A G; Urlings, H F; Sturmans, F

1994-06-01

304

Chemical composition, functional and sensory characteristics of wheat-taro composite flours and biscuits.  

PubMed

The physicochemical, alveographic and sensory characteristics of precooked taro-wheat composite flours and their biscuits were investigated. A 2x7 factorial design consisting of two varieties of taro flour (Red Ibo Ngaoundere, RIN, and egg-like varieties) and 7 levels of wheat substitutions (0, 5, 10, 15, 20, 25 and 30 %) was used for this purpose. It was observed that water absorption capacity (range 95-152 g/100 g), water solubility index (range 18.8-29.5 g/100 g) and swelling capacity (range 125.4-204.6 mL/100 g) of composite flours significantly (p?

Himeda, Makhlouf; Njintang Yanou, Nicolas; Fombang, Edith; Facho, Balaam; Kitissou, Pierre; Mbofung, Carl M F; Scher, Joel

2014-09-01

305

Capsaicin and sensory neurones: a historical perspective.  

PubMed

Capsaicin, the pungent ingredient of red pepper has become not only a "hot" topic in neuroscience but its new target-related unique actions have opened the door for the drug industry to introduce a new chapter of analgesics. After several lines of translational efforts with over 1,000 patents and clinical trials, the 8% capsaicin dermal patch reached the market and its long-lasting local analgesic effect in some severe neuropathic pain states is now well established. This introductory chapter outlines on one hand the historical background based on the author's 50 years of experience in this field and on the other hand emphasizes new scopes, fascinating perspectives in pharmaco-physiology, and molecular pharmacology of nociceptive sensory neurons. Evidence for the effect of capsaicin on C-polymodal nociceptors (CMH), C-mechanoinsensitive (CHMi), and silent C-nociceptors are listed and the features of the capsaicin-induced blocking effects of nociceptors are demonstrated. Common and different characteristics of nociceptor-blocking actions after systemic, perineural, local, intrathecal, and in vitro treatments are summarized. Evidence for the misleading conclusions drawn from neonatal capsaicin pretreatment is presented. Perspectives opened from cloning the capsaicin receptor "Transient Receptor Potential Vanilloid 1" (TRPV1) are outlined and potential molecular mechanisms behind the long-lasting functional, ultrastructural, and nerve terminal-damaging effects of capsaicin and other TRPV1 agonists are summarized. Neurogenic inflammation and the long-list of "capsaicin-sensitive" tissue responses are mediated by an unorthodox dual sensory-efferent function of peptidergic TRPV1-expressing nerve terminals which differ from the classical efferent and sensory nerve endings that have a unidirectional role in neuroregulation. Thermoregulatory effects of capsaicin are discussed in detail. It is suggested that since hyperthermia and burn risk due to enhanced noxious heat threshold are the major obstacles of some TRPV1 antagonists, they could be overcome. The special "multisteric" gating function of the TRPV1 cation channel provides the structural ground for blocking chemical activation of TRPV1 without affecting its responsiveness to physical stimuli. A new chapter of potential analgesics targeting nociceptors is now already supported for pain relief in persistent pathological pain states. PMID:24941663

Szolcsányi, János

2014-01-01

306

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

PubMed

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 minocycline to treat diabetic neuropathy. PMID:25158309

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

2014-11-01

307

Exploring Structural Dynamics within and between Sensory and Intellectual Functioning in Old and Very Old Age: Longitudinal Evidence from the Berlin Aging Study  

ERIC Educational Resources Information Center

Cross-sectional and longitudinal analyses of age-heterogeneous samples have revealed correlational links between and within intellectual, sensory, and sensorimotor domains. Due to basic limitations of cross-sectional designs and a reluctance to disentangle antecedent-consequent relations in longitudinal designs, the functional significance and…

Ghisletta, Paolo; Lindenberger, Ulman

2005-01-01

308

Endogenous NGF and CNTF levels in human peripheral nerve injury.  

PubMed

Nerve growth factor (NGF) is trophic to sensory and sympathetic fibres, and ciliary neurotrophic factor (CNTF) to motoneurones, in animal models of peripheral nerve injury: NGF excess produces hyperalgesia. In this first study of injured human nerves and sensory ganglia, we quantified and localized endogenous NGF and CNTF in 59 neonate and adult patients with brachial plexus and peripheral nerve injury. NGF levels were generally depleted in injured nerves, but relatively preserved acutely in nerve segments distal to injury. NGF immunostaining was observed in Schwann cells in distal nerve segments with pockets of high levels in some neuromas. CNTF levels and immunostaining in Schwann cells were markedly decreased distally within days of injury. We propose that early local administration of NGF and CNTF-like agents may help prevent degenerative changes in injured nerves, while at later stages local anti-NGF treatment (e.g. of some neuromas) may ameliorate chronic pain. PMID:9223080

Anand, P; Terenghi, G; Birch, R; Wellmer, A; Cedarbaum, J M; Lindsay, R M; Williams-Chestnut, R E; Sinicropi, D V

1997-05-27

309

GLIAL RESPONSES AFTER CHORDA TYMPANI NERVE INJURY  

PubMed Central

The chorda tympani (CT) nerve innervates lingual taste buds and is susceptible to damage during dental and inner ear procedures. Interruption of the CT results in a disappearance of taste buds, which can be accompanied by taste disturbances. Because the CT usually regenerates to reinnervate taste buds successfully in a few weeks, a persistence of taste disturbances may indicate alterations in central nervous function. Peripheral injury to other sensory nerves leads to glial responses at central terminals, which actively contribute to abnormal sensations arising from nerve damage. Therefore, the current study examined microglial and astrocytic responses in the first central gustatory relay -the nucleus of the solitary tract (nTS)- after transection of the CT. Damage to the CT resulted in significant microglial responses in terms of morphological reactivity and an increased density of microglial cells from 2-20 days after injury. This increased microglial population primarily resulted from microglial proliferation from 1.5-3 days, which was supplemented by microglial migration within sub-divisions of the nTS between days 2-3. Unlike other nerve injuries, CT injury did not result in recruitment of bone marrow-derived precursors. Astrocytes also reacted in the nTS with increased levels of GFAP by 3 days, although none showed evidence of cell division. GFAP levels remained increased at 30 days by which time microglial responses had resolved. These results show that nerve damage to the CT results in central glial responses, which may participate in long lasting taste alterations following CT lesion. PMID:22315167

Bartel, Dianna L.

2013-01-01

310

Nonthermal ablation with microbubble-enhanced focused ultrasound close to the optic tract without affecting nerve function  

PubMed Central

Object Tumors at the skull base are challenging for both resection and radiosurgery given the presence of critical adjacent structures, such as cranial nerves, blood vessels, and brainstem. Magnetic resonance imaging–guided thermal ablation via laser or other methods has been evaluated as a minimally invasive alternative to these techniques in the brain. Focused ultrasound (FUS) offers a noninvasive method of thermal ablation; however, skull heating limits currently available technology to ablation at regions distant from the skull bone. Here, the authors evaluated a method that circumvents this problem by combining the FUS exposures with injected microbubble-based ultrasound contrast agent. These microbubbles concentrate the ultrasound-induced effects on the vasculature, enabling an ablation method that does not cause significant heating of the brain or skull. Methods In 29 rats, a 525-kHz FUS transducer was used to ablate tissue structures at the skull base that were centered on or adjacent to the optic tract or chiasm. Low-intensity, low-duty-cycle ultrasound exposures (sonications) were applied for 5 minutes after intravenous injection of an ultrasound contrast agent (Definity, Lantheus Medical Imaging Inc.). Using histological analysis and visual evoked potential (VEP) measurements, the authors determined whether structural or functional damage was induced in the optic tract or chiasm. Results Overall, while the sonications produced a well-defined lesion in the gray matter targets, the adjacent tract and chiasm had comparatively little or no damage. No significant changes (p > 0.05) were found in the magnitude or latency of the VEP recordings, either immediately after sonication or at later times up to 4 weeks after sonication, and no delayed effects were evident in the histological features of the optic nerve and retina. Conclusions This technique, which selectively targets the intravascular microbubbles, appears to be a promising method of noninvasively producing sharply demarcated lesions in deep brain structures while preserving function in adjacent nerves. Because of low vascularity—and thus a low microbubble concentration—some large white matter tracts appear to have some natural resistance to this type of ablation compared with gray matter. While future work is needed to develop methods of monitoring the procedure and establishing its safety at deep brain targets, the technique does appear to be a potential solution that allows FUS ablation of deep brain targets while sparing adjacent nerve structures. PMID:24010975

McDannold, Nathan; Zhang, Yong-Zhi; Power, Chanikarn; Jolesz, Ferenc; Vykhodtseva, Natalia

2014-01-01

311

Sensory Arrays of Covalently Functionalized Single-Walled Carbon Nanotubes for Explosive Detection  

E-print Network

Chemiresistive sensor arrays for cyclohexanone and nitromethane are fabricated using single-walled carbon nanotubes (SWCNTs) that are covalently functionalized with urea, thiourea, and squaramide containing selector units. ...

van der Zwaag, Daan

312

Improving the Functionality of Intra-Operative Nerve Monitoring During Thyroid Surgery: Is Lidocaine an Option?  

PubMed Central

Intra-operative nerve monitoring (IONM) is rapidly becoming a standard of care in many institutions across the country. In the absence of neuromuscular blocking agents to facilitate the IONM, the depth of anesthesia required to abolish the laryngo tracheal reflexes often results in profound hemodynamic instability during surgery, necessitating the use of large doses of sympathomimetic amines. The excessive alpha and beta adrenergic effects exhibited by these agents are undesirable in the presence of cardiovascular co-morbidities. Trying to strike a balance frequently results in an unsatisfactory intra-operative course. In the course of the near total thyroidectomy performed on a 60-year-old female, we employed lidocaine infusion at 1.5 mg/kg/hour following a bolus dose of 1 mg/kg. The troublesome laryngo tracheal reflexes were successfully blunted and we were able to moderate the depth of anesthesia resulting in stable hemodynamics. A bispectral index monitor was employed to guard against “recall” and a train of four monitor was used to ensure the absence of inadvertent neuromuscular blockade. During the surgery, there was loss of signal on the left recurrent laryngeal nerve (RLN). The signal strength was restored by rotating the endotracheal tube on its long axis to realign the electrode with the vocal cords under Glidescope® visualization.

Govindarajan, Ramasamy; Shah, Ajay; Reddy, Vemuru Sunil; Parithivel, Vellore; Ravikumar, Saiganesh; Livingstone, Dave

2015-01-01

313

Impact of Anesthetics on Immune Functions in a Rat Model of Vagus Nerve Stimulation  

PubMed Central

Vagus nerve stimulation (VNS) has been successfully performed in animals for the treatment of different experimental models of inflammation. The anti-inflammatory effect of VNS involves the release of acetylcholine by vagus nerve efferent fibers inhibiting pro-inflammatory cytokines (e.g. TNF-?) produced by macrophages. Moreover, it has recently been demonstrated that splenic lymphocytic populations may also be involved. As anesthetics can modulate the inflammatory response, the current study evaluated the effect of two different anesthetics, isoflurane and pentobarbital, on splenic cellular and molecular parameters in a VNS rat model. Spleens were collected for the characterization of lymphocytes sub-populations by flow cytometry and quantification of cytokines secretion after in vitro activation. Different results were observed depending on the anesthetic used. The use of isoflurane displayed a non-specific effect of VNS characterized by a decrease of most splenic lymphocytes sub-populations studied, and also led to a significantly lower TNF-? secretion by splenocytes. However, the use of pentobarbital brought to light immune modifications in non-stimulated animals that were not observed with isoflurane, and also revealed a specific effect of VNS, notably at the level of T lymphocytes’ activation. These differences between the two anesthetics could be related to the anti-inflammatory properties of isoflurane. In conclusion, pentobarbital is more adapted than isoflurane in the study of the anti-inflammatory effect of VNS on an anesthetized rat model in that it allows more accurate monitoring of subtle immunomodulatory processes. PMID:23840592

Picq, Chloé A.; Clarençon, Didier; Sinniger, Valérie E.; Bonaz, Bruno L.; Mayol, Jean-François S.

2013-01-01

314

Theobromine inhibits sensory nerve activation and cough  

Microsoft Academic Search

Cough is a common and protective reflex, but persistent coughing is debilitating and impairs quality of life. Antitussive treatment using opioids is limited by unacceptable side effects, and there is a great need for more effective remedies. The present study demonstrates that theobromine, a methylxanthine derivative present in cocoa, effectively inhibits citric acid- induced cough in guinea-pigs in vivo. Furthermore,

Omar S. Usmani; Maria G. Belvisi; Hema J. Patel; Natascia Crispino; Mark A. Birrell; Márta Korbonits; Peter J. Barnes

2004-01-01

315

Evaluation and use of regenerative multi electrode interfaces in peripheral nerves  

NASA Astrophysics Data System (ADS)

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 explores the discrimination between motor and proprioceptive origin of this bursting activity and reports the identified efferent motor nature, as well as the demonstration of a significant and stable correlation with the activity of distal muscle involved in locomotion. In summary, sensory-motor neural activity was recorded chronically by REMI electrodes with high SNR which serves as a tool for evaluating firing patterns of specific axon types during voluntary movement or sensory stimulation. In turn, this interface can be used to improve motor control and sensory feedback in closed loop systems for robotic prosthesis.

Desai, Vidhi

316

THE ROLE OF GLYOXALASE I IN HYPERGLYCEMIA-INDUCED SENSORY NEURON DAMAGE AND DEVELOPMENT OF DIABETIC SENSORY NEUROPATHY SYMPTOMS  

E-print Network

Diabetic neuropathy is the most common and debilitating complication of diabetes mellitus with over half of all patients developing altered sensation as a result of damage to peripheral sensory neurons. Hyperglycemia results in altered nerve...

Jack, Megan Marie

2011-08-31

317

Preferential and comprehensive reconstitution of severely damaged sciatic nerve using murine skeletal muscle-derived multipotent stem cells.  

PubMed

Loss of vital functions in the somatic motor and sensory nervous systems can be induced by severe peripheral nerve transection with a long gap following trauma. In such cases, autologous nerve grafts have been used as the gold standard, with the expectation of activation and proliferation of graft-concomitant Schwann cells associated with their paracrine effects. However, there are a limited number of suitable sites available for harvesting of nerve autografts due to the unavoidable sacrifice of other healthy functions. To overcome this problem, the potential of skeletal muscle-derived multipotent stem cells (Sk-MSCs) was examined as a novel alternative cell source for peripheral nerve regeneration. Cultured/expanded Sk-MSCs were injected into severely crushed sciatic nerve corresponding to serious neurotmesis. After 4 weeks, engrafted Sk-MSCs preferentially differentiated into not only Schwann cells, but also perineurial/endoneurial cells, and formed myelin sheath and perineurium/endoneurium, encircling the regenerated axons. Increased vascular formation was also observed, leading to a favorable blood supply and waste product excretion. In addition, engrafted cells expressed key neurotrophic and nerve/vascular growth factor mRNAs; thus, endocrine/paracrine effects for the donor/recipient cells were also expected. Interestingly, skeletal myogenic capacity of expanded Sk-MSCs was clearly diminished in peripheral nerve niche. The same differentiation and tissue reconstitution capacity of Sk-MSCs was sufficiently exerted in the long nerve gap bridging the acellular conduit, which facilitated nerve regeneration/reconnection. These effects represent favorable functional recovery in Sk-MSC-treated mice, as demonstrated by good corduroy walking. We also demonstrated that these differentiation characteristics of the Sk-MSCs were comparable to native peripheral nerve-derived cells, whereas the therapeutic capacities were largely superior in Sk-MSCs. Therefore, Sk-MSCs can be a novel/suitable alternative cell source for healthy nerve autografts. PMID:24614849

Tamaki, Tetsuro; Hirata, Maki; Soeda, Shuichi; Nakajima, Nobuyuki; Saito, Kosuke; Nakazato, Kenei; Okada, Yoshinori; Hashimoto, Hiroyuki; Uchiyama, Yoshiyasu; Mochida, Joji

2014-01-01

318

Preferential and Comprehensive Reconstitution of Severely Damaged Sciatic Nerve Using Murine Skeletal Muscle-Derived Multipotent Stem Cells  

PubMed Central

Loss of vital functions in the somatic motor and sensory nervous systems can be induced by severe peripheral nerve transection with a long gap following trauma. In such cases, autologous nerve grafts have been used as the gold standard, with the expectation of activation and proliferation of graft-concomitant Schwann cells associated with their paracrine effects. However, there are a limited number of suitable sites available for harvesting of nerve autografts due to the unavoidable sacrifice of other healthy functions. To overcome this problem, the potential of skeletal muscle-derived multipotent stem cells (Sk-MSCs) was examined as a novel alternative cell source for peripheral nerve regeneration. Cultured/expanded Sk-MSCs were injected into severely crushed sciatic nerve corresponding to serious neurotmesis. After 4 weeks, engrafted Sk-MSCs preferentially differentiated into not only Schwann cells, but also perineurial/endoneurial cells, and formed myelin sheath and perineurium/endoneurium, encircling the regenerated axons. Increased vascular formation was also observed, leading to a favorable blood supply and waste product excretion. In addition, engrafted cells expressed key neurotrophic and nerve/vascular growth factor mRNAs; thus, endocrine/paracrine effects for the donor/recipient cells were also expected. Interestingly, skeletal myogenic capacity of expanded Sk-MSCs was clearly diminished in peripheral nerve niche. The same differentiation and tissue reconstitution capacity of Sk-MSCs was sufficiently exerted in the long nerve gap bridging the acellular conduit, which facilitated nerve regeneration/reconnection. These effects represent favorable functional recovery in Sk-MSC-treated mice, as demonstrated by good corduroy walking. We also demonstrated that these differentiation characteristics of the Sk-MSCs were comparable to native peripheral nerve-derived cells, whereas the therapeutic capacities were largely superior in Sk-MSCs. Therefore, Sk-MSCs can be a novel/suitable alternative cell source for healthy nerve autografts. PMID:24614849

Tamaki, Tetsuro; Hirata, Maki; Soeda, Shuichi; Nakajima, Nobuyuki; Saito, Kosuke; Nakazato, Kenei; Okada, Yoshinori; Hashimoto, Hiroyuki; Uchiyama, Yoshiyasu; Mochida, Joji

2014-01-01

319

Palmar cutaneous nerve conduction in patients with carpal tunnel syndrome.  

PubMed

Objective: This study aimed to assess palmar cutaneous branch of the median nerve (PCBm) conduction in patients with clinically diagnosed carpal tunnel syndrome (CTS), to compare PCBm conduction with that of the median and ulnar nerves, and to determine the PCBm conduction abnormality rate in patients with CTS. Materials and Methods: The study included 99 hands of 60 patients with clinical CTS and 38 hands of 38 healthy controls. Sensory nerve conduction study (NCS) was performed on the median nerve, ulnar nerve, and PCBm, and onset latency, conduction velocity and amplitude were recorded. Additionally, differences in latency and velocity between the median nerve and PCBm, and the difference in latency between the median and ulnar nerves were calculated. Results: In all, 56% of the patients with CTS had abnormal PCBm conduction. Additionally, in 7 of 8 hands with abnormal sensation -both in the thenar eminence and abnormal sensory distribution along the main branch -NCS of the PCBm was also abnormal. Conclusions: The PCBm is not ideal as a comparator nerve for the neurophysiological diagnosis of CTS. The frequency of PCBm abnormality in CTS patients may be related to the concomitant damage in both of these nerves. Additionally, the present findings may help explain, at least in part, why patients with CTS often exhibit sensory involvement beyond the classical median nerve sensory borders. PMID:25271802

Uluc, Kayihan; Aktas, Ilknur; Sunter, Gulin; Kahraman Koytak, Pinar; Akyuz, Gulseren; Isak, Baris; Tanridag, Tulin; Us, Onder

2014-11-01

320

Type III Nrg1 back signaling enhances functional TRPV1 along sensory axons contributing to basal and inflammatory thermal pain sensation.  

PubMed

Type III Nrg1, a member of the Nrg1 family of signaling proteins, is expressed in sensory neurons, where it can signal in a bi-directional manner via interactions with the ErbB family of receptor tyrosine kinases (ErbB RTKs). Type III Nrg1 signaling as a receptor (Type III Nrg1 back signaling) can acutely activate phosphatidylinositol-3-kinase (PtdIns3K) signaling, as well as regulate levels of ?7* nicotinic acetylcholine receptors, along sensory axons. Transient receptor potential vanilloid 1 (TRPV1) is a cation-permeable ion channel found in primary sensory neurons that is necessary for the detection of thermal pain and for the development of thermal hypersensitivity to pain under inflammatory conditions. Cell surface expression of TRPV1 can be enhanced by activation of PtdIns3K, making it a potential target for regulation by Type III Nrg1. We now show that Type III Nrg1 signaling in sensory neurons affects functional axonal TRPV1 in a PtdIns3K-dependent manner. Furthermore, mice heterozygous for Type III Nrg1 have specific deficits in their ability to respond to noxious thermal stimuli and to develop capsaicin-induced thermal hypersensitivity to pain. Cumulatively, these results implicate Type III Nrg1 as a novel regulator of TRPV1 and a molecular mediator of nociceptive function. PMID:21949864

Canetta, Sarah E; Luca, Edlira; Pertot, Elyse; Role, Lorna W; Talmage, David A

2011-01-01

321

The central projections of the laryngeal nerves in the rat  

PubMed Central

The larynx serves respiratory, protective, and phonatory functions. The motor and sensory innervation to the larynx controlling these functions is provided by the superior laryngeal nerve (SLN) and the recurrent laryngeal nerve (RLN). Classical studies state that the SLN innervates the cricothyroid muscle and provides sensory innervation to the supraglottic cavity, whereas the RLN supplies motor innervation to the remaining intrinsic laryngeal muscles and sensory innervation to the infraglottic cavity, but recent data suggest a more complex anatomical and functional organisation. The current neuroanatomical tracing study was undertaken to provide a comprehensive description of the central brainstem connections of the axons within the SLN and the RLN, including those neurons that innervate the larynx. The study has been carried out in 41 adult male Sprague–Dawley rats. The central projections of the laryngeal nerves were labelled following application of biotinylated dextran amines onto the SLN, the RLN or both. The most remarkable result of the study is that in the rat the RLN does not contain any afferent axons from the larynx, in contrast to the pattern observed in many other species including man. The RLN supplied only special visceromotor innervation to the intrinsic muscles of the larynx from motoneurons in the nucleus ambiguus (Amb). All the afferent axons innervating the larynx are contained within the SLN, and reach the nucleus of the solitary tract. The SLN also contained secretomotor efferents originating from motoneurons in the dorsal motor nucleus of the vagus, and special visceral efferent fibres from the Amb. In conclusion, the present study shows that in the rat the innervation of the larynx differs in significant ways from that described in other species. PMID:21599662

Pascual-Font, Arán; Hernández-Morato, Ignacio; McHanwell, Stephen; Vázquez, Teresa; Maranillo, Eva; Sañudo, Jose; Valderrama-Canales, Francisco J

2011-01-01

322

Evaluation of the efficacy of a novel radical neck dissection preserving the external jugular vein, greater auricular nerve, and deep branches of the cervical nerve  

PubMed Central

Background Conventional radical neck dissection often causes a variety of complications. Although the dissection method has been improved by retaining some tissues to reduce complications, the incomplete dissection may cause recurrence of disease. In the present study, we developed a novel radical neck dissection, which preserves the external jugular vein, the greater auricular nerve, and the deep branches of the cervical nerve, to effectively reduce complications and subsequently, to promote the postoperative survival quality. Methods A total of 100 cases of radical neck dissection were retrospectively analyzed to evaluate the efficacy, rate of complication, and postoperative dysfunction of patients treated with the novel radical neck dissection. Data analysis was performed using the Chi-square test. Results Compared with conventional radical neck dissection, the novel radical neck dissection could significantly reduce complications and promote postoperative survival quality. Particularly, the preservation of the external jugular vein reduced the surgical risk (ie, intracranial hypertension) and complications (eg, facial edema, dizziness, headache). Preservation of the deep branches of the cervical nerve and greater auricular nerve resulted in relatively ideal postoperative functions of the shoulders and ear skin sensory function (P < 0.05), while the two types of dissection procedures showed no differences in the recurrence rate (P > 0.05). Conclusion Our novel radical neck dissection procedure could effectively reduce the complications of intracranial hypertension, shoulder dysfunction, and ear sensory disturbances. It can be used as a regular surgical approach for oral carcinoma radical neck dissection. PMID:23596353

Li, Yadong; Zhang, Jinsong; Yang, Kai

2013-01-01

323

The influence of feeding on the evolution of sensory signals: a comparative test of an evolutionary trade-off between masticatory and sensory functions of skulls in southern African Horseshoe bats (Rhinolophidae).  

PubMed

The skulls of animals have to perform many functions. Optimization for one function may mean another function is less optimized, resulting in evolutionary trade-offs. Here, we investigate whether a trade-off exists between the masticatory and sensory functions of animal skulls using echolocating bats as model species. Several species of rhinolophid bats deviate from the allometric relationship between body size and echolocation frequency. Such deviation may be the result of selection for increased bite force, resulting in a decrease in snout length which could in turn lead to higher echolocation frequencies. If so, there should be a positive relationship between bite force and echolocation frequency. We investigated this relationship in several species of southern African rhinolophids using phylogenetically informed analyses of the allometry of their bite force and echolocation frequency and of the three-dimensional shape of their skulls. As predicted, echolocation frequency was positively correlated with bite force, suggesting that its evolution is influenced by a trade-off between the masticatory and sensory functions of the skull. In support of this, variation in skull shape was explained by both echolocation frequency (80%) and bite force (20%). Furthermore, it appears that selection has acted on the nasal capsules, which have a frequency-specific impedance matching function during vocalization. There was a negative correlation between echolocation frequency and capsule volume across species. Optimization of the masticatory function of the skull may have been achieved through changes in the shape of the mandible and associated musculature, elements not considered in this study. PMID:25393780

Jacobs, D S; Bastian, A; Bam, L

2014-12-01

324

Chemical composition, techno-functional and sensory properties and effects of three dietary fibers on the quality characteristics of Tunisian beef sausage.  

PubMed

This study determined the effects of three dietary fibers namely, VITACEL LC200 powdered cellulose (LC200), barley beta-glucan concentrate (BBC), and VITACEL KF500 potato fiber (KF500), on the techno-functional and sensory properties and quality characteristics of Tunisian beef sausage. The findings revealed interesting functional properties for LC200 fiber. This fiber displayed high water binding capacity (WBC) and oil binding capacity (OBC), values of 16.2 g/g and 10.2 g/g, respectively, which are higher than reported for most fruit and vegetable fiber concentrates. The application of LC200 improved the masticability and elasticity of beef sausage formulations and minimized their hardness and production costs without negatively affecting their sensory properties. Overall, the findings demonstrate the potential functional and economic utility of LC200 fiber as a promising source of dietary fiber. PMID:24013695

Ktari, Naourez; Smaoui, Slim; Trabelsi, Imen; Nasri, Moncef; Ben Salah, Riadh

2014-01-01

325

Intrinsic Signal Changes Accompanying Sensory Stimulation: Functional Brain Mapping with Magnetic Resonance Imaging  

Microsoft Academic Search

We report that visual stimulation produces an easily detectable (5-20%) transient increase in the intensity of water proton magnetic resonance signals in human primary visual cortex in gradient echo images at 4-T magnetic-field strength. The observed changes predominantly occur in areas containing gray matter and can be used to produce high-spatial-resolution functional brain maps in humans. Reducing the image-acquisition echo

Seiji Ogawa; David W. Tank; Ravi Menon; Jutta M. Ellermann; Seong-Gi Kim; Hellmut Merkle; Kamil Ugurbil

1992-01-01

326

Improvement of functional recovery of transected peripheral nerve by means of chitosan grafts filled with vitamin E, pyrroloquinoline quinone and their combination.  

PubMed

Effects of vitamin E and pyrroloquinoline quinone on peripheral nerve regeneration were studied using a rat sciatic nerve transection model. Ninety male healthy White Wistar rats were divided into three experimental groups (n = 15), randomly: Sham-operation (SHAM), transected control (TC), chitosan conduit (Chit) and three treatment groups (Vit E, PQQ and PQQ + Vit E). In SHAM group after anesthesia, left sciatic nerve was exposed through a gluteal muscle incision and after homeostasis muscle was sutured. In Chit group left sciatic nerve was exposed the same way and transected proximal to tibio-peroneal bifurcation leaving a 10-mm gap. Proximal and distal stumps were each inserted into a chitosan tube. In treatment groups the tube was implanted the same way and filled with Vit E, PQQ and PQQ + Vit E. Each group was subdivided into three subgroups of six animals each and were studied 4, 8, 12 weeks after surgery. Functional and electrophysiological studies, and gastrocnemius muscle mass measurement confirmed faster and better recovery of regenerated axons in Vit E + PQQ combination compared to Vit E or PQQ solely (P < 0.05). Morphometric indices of regenerated fibers showed number and diameter of the myelinated fibers in PQQ + Vit E was significantly higher than in other treatment groups. In immunohistochemistry, location of reactions to S-100 in PQQ + Vit E was clearly more positive than in other treatment groups. Response to PQQ + Vit E treatment demonstrates that it influences and improves functional recovery of peripheral nerve regeneration. PMID:24129003

Azizi, Asghar; Azizi, Saeed; Heshmatian, Behnam; Amini, Keyvan

2014-01-01

327

A microfluidic phenotype analysis system reveals function of sensory and dopaminergic neuron signaling in C. elegans electrotactic swimming behavior  

PubMed Central

The nematode (worm) C. elegans is a leading multicellular animal model to study neuronal-basis of behavior. Worms respond to a wide range of stimuli and exhibit characteristic movement patterns. Here we describe the use of a microfluidics setup to probe neuronal activity that relies on the innate response of C. elegans to swim toward the cathode in the presence of a DC electric field (termed “electrotaxis”). Using this setup, we examined mutants affecting sensory and dopaminergic neurons and found that their electrotactic responses were defective. Such animals moved with reduced speed (35–80% slower than controls) with intermittent pauses, abnormal turning and slower body bends. A similar phenotype was observed in worms treated with neurotoxins 6-OHDA (6- hydroxy dopamine), MPTP (1-methyl 4-phenyl 1,2,3,6-tetrahydropyridine) and rotenone (20–60% slower). We also found that neurotoxin effects could be suppressed by pre-exposing worms to a known neuroprotective compound acetaminophen. Collectively, these results show that microfluidic electrotaxis can identify alterations in dopamine and amphid neuronal signaling based on swimming responses of C. elegans. Further characterization has revealed that the electrotactic swimming response is highly sensitive and reliable in detecting neuronal abnormalities. Thus, our microfluidics setup could be used to dissect neuronal function and toxin-induced neurodegeneration. Among other applications, the setup promises to facilitate genetic and chemical screenings to identify factors that mediate neuronal signaling and neuroprotection. PMID:24058875

Salam, Sangeena; Ansari, Ata; Amon, Siavash; Rezai, Pouya; Selvaganapathy, P. Ravi; Mishra, Ram K.; Gupta, Bhagwati P.

2013-01-01

328

The effects of functional magnetic nanotubes with incorporated nerve growth factor in neuronal differentiation of PC12 cells  

NASA Astrophysics Data System (ADS)

In this in vitro study the efficiency of magnetic nanotubes to bind with nerve growth factor (NGF) and the ability of NGF-incorporated magnetic nanotubes to release the bound NGF are investigated using rat pheochromocytoma cells (PC12 cells). It is found that functional magnetic nanotubes with NGF incorporation enabled the differentiation of PC12 cells into neurons exhibiting growth cones and neurite outgrowth. Microscope observations show that filopodia extending from neuron growth cones were in close proximity to the NGF-incorporated magnetic nanotubes, at times appearing to extend towards or into them. These results show that magnetic nanotubes can be used as a delivery vehicle for NGF and thus may be exploited in attempts to treat neurodegenerative disorders such as Parkinson's disease with neurotrophins. Further neurite outgrowth can be controlled by manipulating magnetic nanotubes with external magnetic fields, thus helping in directed regeneration.

Xie, Jining; Chen, Linfeng; Varadan, Vijay K.; Yancey, Justin; Srivatsan, Malathi

2008-03-01

329

Pseudo third cranial nerve palsy secondary to orbital ectopic lacrimal gland cyst: management with functional endoscopic sinus surgery.  

PubMed

An otherwise healthy 13-month-old girl was noted by her pediatrician to have developed a left head turn. The patient was referred to a pediatric ophthalmologist, who noticed signs of incomplete third cranial nerve palsy. Magnetic resonance imaging revealed the presence of an abnormal lesion in the inferonasal orbit that was abutting the ethmoid sinus. After consultation with an ENT specialist, the decision was made to remove the lesion via functional endoscopic sinus surgery because this approach was deemed to provide adequate access while limiting morbidity. Histology of the excised lesion identified it as true ectopic lacrimal gland tissue with cysts. We recognize and comment on the fact that in many reported cases of ectopic lacrimal gland cyst, the tissue was not ectopic at all but instead represented an extension of normal lacrimal gland tissue. PMID:24526481

Braich, Puneet S; Silbert, Jonathan E; Levada, Andrew J; Schiff, Neil R

2014-02-01

330

Implications of Sensory Stimulation in Self-Destructive Behavior.  

ERIC Educational Resources Information Center

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)

Edelson, Stephen M.

1984-01-01

331

Dysfunctional penile cholinergic nerves in diabetic impotent men  

SciTech Connect

Impotence in the diabetic man may be secondary to a neuropathic condition of the autonomic penile nerves. The relationship between autonomic neuropathy and impotence in diabetes was studied in human corporeal tissue obtained during implantation of a penile prosthesis in 19 impotent diabetic and 15 nondiabetic patients. The functional status of penile cholinergic nerves was assessed by determining their ability to accumulate tritiated choline (34), and synthesize (34) and release (19) tritiated-acetylcholine after incubation of corporeal tissue with tritiated-choline (34). Tritiated-choline accumulation, and tritiated-acetylcholine synthesis and release were significantly reduced in the corporeal tissue from diabetic patients compared to that from nondiabetic patients (p less than 0.05). The impairment in acetylcholine synthesis worsened with the duration of diabetes (p less than 0.025). No differences in the parameters measured were found between insulin-dependent (11) and noninsulin-dependent (8) diabetic patients. The ability of the cholinergic nerves to synthesize acetylcholine could not be predicted clinically with sensory vibration perception threshold testing. It is concluded that there is a functional penile neuropathic condition of the cholinergic nerves in the corpus cavernosum of diabetic impotent patients that may be responsible for the erectile dysfunction.

Blanco, R.; Saenz de Tejada, I.; Goldstein, I.; Krane, R.J.; Wotiz, H.H.; Cohen, R.A. (Boston Univ. School of Medicine, MA (USA))

1990-08-01

332

Neurological function following intra-neural injection of fluorescent neuronal tracers in rats?  

PubMed Central

Fluorescent neuronal tracers should not be toxic to the nervous system when used in long-term labeling. Previous studies have addressed tracer toxicity, but whether tracers injected into an intact nerve result in functional impairment remains to be elucidated. In the present study, we examined the functions of motor, sensory and autonomic nerves following the application of 5% Fluoro-Gold, 4% True Blue and 10% Fluoro-Ruby (5 ?L) to rat tibial nerves via pressure injection. A set of evaluation methods including walking track analysis, plantar test and laser Doppler perfusion imaging was used to determine the action of the fluorescent neuronal tracers. Additionally, nerve pathology and ratio of muscle wet weight were also observed. Results showed that injection of Fluoro-Gold significantly resulted in loss of motor nerve function, lower plantar sensibility, increasing blood flow volume and higher neurogenic vasodilatation. Myelinated nerve fiber degeneration, unclear boundaries in nerve fibers and high retrograde labeling efficacy were observed in the Fluoro-Gold group. The True Blue group also showed obvious neurogenic vasodilatation, but less severe loss of motor function and degeneration, and fewer labeled motor neurons were found compared with the Fluoro-Gold group. No anomalies of motor and sensory nerve function and no myelinated nerve fiber degeneration were observed in the Fluoro-Ruby group. Experimental findings indicate that Fluoro-Gold tracing could lead to significant functional impairment of motor, sensory and autonomic nerves, while functional impairment was less severe following True Blue tracing. Fluoro-Ruby injection appears to have no effect on neurological function. PMID:25206419

Hu, Wen; Liu, Dan; Zhang, Yanping; Shen, Zhongyi; Gu, Tianwen; Gu, Xiaosong; Gu, Jianhui

2013-01-01

333

Advances in nerve repair.  

PubMed

Patients with peripheral nerve injuries face unpredictable and often suboptimal functional outcome, even following standard microsurgical nerve repair. The challenge of improving such outcomes following nerve surgical procedures has interested many research teams, in both clinical and fundamental fields. Some innovative treatments are presently being applied to a widening range of patients, whereas others will require further development before translation to human subjects. This article presents several recent advances in emerging therapies at various stages of clinical application. Nerve transfers have been successfully used in clinical settings, but new indications are being described, enlarging the range of patients who might benefit from them. Brief direct nerve electrical stimulation has been shown to improve nerve regeneration and outcome in animal models and in a small cohort of patients. Further clinical trials are warranted to prove the efficacy of this exciting and easily applicable approach. Animal studies also suggest a tremendous potential for stem and precursor cell therapy. Further studies will lead to a better understanding of their mechanisms of action in nerve repair and potential applications for human patients. PMID:23250767

Khuong, Helene T; Midha, Rajiv

2013-01-01

334

Increased substance P content in nerve fibers associated with mesenteric veins from deoxycorticosterone acetate (DOCA)-salt hypertensive rats  

Microsoft Academic Search

This study examined sensory nerves associated with mesenteric arteries and veins in sham and deoxycorticosterone acetate (DOCA)-salt hypertensive rats. Reactivity of arteries and veins to substances released from sensory nerves was also studied in vitro using computer-assisted video microscopy. Co-localization of substance P (SP) and calcitonin gene-related peptide (CGRP) immunoreactivity (ir) was used to evaluate perivascular sensory nerves. Radioimmunoassay was

James J. Galligan; Sara B. Miller; Khurshed Katki; Scott Supowit; Donald DiPette; Gregory D. Fink

2006-01-01

335

Synthetic Self-Assembling Clostridial Chimera for Modulation of Sensory Functions  

PubMed Central

Clostridial neurotoxins reversibly block neuronal communication for weeks and months. While these proteolytic neurotoxins hold great promise for clinical applications and the investigation of brain function, their paralytic activity at neuromuscular junctions is a stumbling block. To redirect the clostridial activity to neuronal populations other than motor neurons, we used a new self-assembling method to combine the botulinum type A protease with the tetanus binding domain, which natively targets central neurons. The two parts were produced separately and then assembled in a site-specific way using a newly introduced ‘protein stapling’ technology. Atomic force microscopy imaging revealed dumbbell shaped particles which measure ?23 nm. The stapled chimera inhibited mechanical hypersensitivity in a rat model of inflammatory pain without causing either flaccid or spastic paralysis. Moreover, the synthetic clostridial molecule was able to block neuronal activity in a defined area of visual cortex. Overall, we provide the first evidence that the protein stapling technology allows assembly of distinct proteins yielding new biomedical properties. PMID:24011174

2013-01-01

336

Structure and function of a peptide pheromone family that stimulate the vomeronasal sensory system in mice.  

PubMed

Mammals use pheromones to communicate with other animals of the same species. In mice, the VNO (vomeronasal organ) has a pivotal role in pheromone detection. We discovered a 7 kDa peptide, ESP1 (exocrine-gland-secreting peptide 1), in tear fluids from male mice that enhances the sexual behaviour of female mice via the VNO. NMR studies demonstrate that ESP1 adopts a compact structure with a helical fold stabilized by an intramolecular disulfide bridge. Functional analysis in combination with docking simulation indicates that ESP1 is recognized by a specific G-protein-coupled vomeronasal receptor, V2Rp5, via charge-charge interactions in the large extracellular region of the receptor. ESP1 is a member of the ESP family, which comprises 38 homologous genes in mice, and some of these genes are expressed in a sex- or age-dependent manner. Most recently, ESP22 was found to be released specifically in juvenile tear fluids and to inhibit the sexual behaviour of adult male mice. These studies demonstrate that peptide pheromones are used for chemical communication in mice, and they indicate a structural basis for the narrowly tuned perception of mammalian peptide pheromones by vomeronasal receptors. PMID:25109971

Abe, Takayuki; Touhara, Kazushige

2014-08-01

337

Functional and Physical Outcomes following Use of a Flexible CO2 Laser Fiber and Bipolar Electrocautery in Close Proximity to the Rat Sciatic Nerve with Correlation to an In Vitro Thermal Profile Model  

PubMed Central

This study compared functional and physical collateral damage to a nerve when operating a Codman MALIS Bipolar Electrosurgical System CMC-III or a CO2 laser coupled to a laser, with correlation to an in vitro model of heating profiles created by the devices in thermochromic ink agarose. Functional damage of the rat sciatic nerve after operating the MALIS or CO2 laser at various power settings and proximities to the nerve was measured by electrically evoked nerve action potentials, and histology of the nerve was used to assess physical damage. Thermochromic ink dissolved in agarose was used to model the spatial and temporal profile of the collateral heating zone of the electrosurgical system and the laser ablation cone. We found that this laser can be operated at 2?W directly above the nerve with minimal damage, while power settings of 5?W and 10?W resulted in acute functional and physical nerve damage, correlating with the maximal heating cone in the thermochromic ink model. MALIS settings up to 40 (11?W) did not result in major functional or physical nerve damage until the nerve was between the forceps tips, correlating with the hottest zone, localized discretely between the tips.

Robinson, A. M.; Fishman, A. J.; Bendok, B. R.; Richter, C.-P.

2015-01-01

338

Irradiating of Bulk Soybeans: Influence on Their Functional and Sensory Properties for Soyfood Processing  

NASA Technical Reports Server (NTRS)

Soybeans were chosen for lunar and planetary missions, where soybeans will be supplied in bulk or grown locally, due to their nutritive value and ability to produce oil and protein for further food applications. However, soybeans must be processed into foods prior to consumption. Radiation that soybeans would be exposed to during bulk storage prior to and during a Mars mission may influence their germination and functional properties. The influence of radiation includes the affect of surface pasteurization to ensure the astronauts safety from food-borne illnesses (HACCP, CCP), and the affect of the amount of radiation the soybeans receive during a Mars mission. Decreases in the amount of natural antioxidants free radical formation, and oxidation-induced changes in the soybean will influence the nutritional value, texture, color, and aroma of soyfoods. The objective of this study was to determine the influence of pasteurization and sterilization surface radiation on whole soybeans using gamma and electron beam radiation. The influence of 0, 1, 5, 10, and 30kGy on microbial load, germination rate, ease of processing, and quality of soymilk and tofu were determined. Surface radiation of whole dry soybeans using electron beam or gamma rays from 1-30kGy did provide microbial safety for the astronauts. However, the lower dose levels had surviving yeasts and molds. These doses caused oxidative changes that resulted in soymilk and tofu with rancid aromas. GC-MS of the aroma compounds using SPME Headspace confirmed the presence of lipid oxidation compounds. Soybean germination ability was reduced as radiation dosage increased. While lower doses may reduce these problems, the ability to insure microbial safety of bulk soybeans will be lost. Counter measures could include vacuum packaging, nitrogen flushing, added antioxidants, and radiating under freezing conditions. Doses below 1kGy need to be investigated further to determine the influence of the radiation encountered during Mars missions.

Chia, Chiew-Ling; Wilson, Lester A.; Boylston, Terri; Perchonok, Michele; French, Stephen

2006-01-01

339

Auditory tasks for assessment of sensory function and affective prosody in schizophrenia.  

PubMed

Schizophrenia patients exhibit impairments in auditory-based social cognition, indicated by deficits in detection of prosody, such as affective prosody and basic pitch perception. However, little is known about the psychometric properties of behavioral tests used to assess these functions. The goal of this paper is to characterize the properties of prosody and pitch perception tasks and to investigate whether they can be shortened. The pitch perception test evaluated is a tone-matching task developed by Javitt and colleagues (J-TMT). The prosody test evaluated is the auditory emotion recognition task developed by Juslin and Laukka (JL-AER). The sample includes 124 schizophrenia patients (SZ) and 131 healthy controls (HC). Properties, including facility and discrimination, of each item were assessed. Effects of item characteristics (e.g., emotion) were also evaluated. Shortened versions of the tests are proposed based on facility, discrimination, and/or ability of item characteristics to discriminate between patients and controls. Test-retest reliability is high for patients and controls for both the original and short forms of the J-TMT and JL-AER. Thus, the original as well as short forms of the J-TMT and JL-AER are suggested for inclusion in clinical trials of social cognitive and perceptual treatments. The development of short forms further increases the utility of these auditory tasks in clinical trials and clinical practice. The large SZ vs. HC differences reported here also highlight the profound nature of auditory deficits and a need for remediation. PMID:25214372

Petkova, Eva; Lu, Feihan; Kantrowitz, Joshua; Sanchez, Jamie L; Lehrfeld, Jonathan; Scaramello, Nayla; Silipo, Gail; DiCostanza, Joanna; Ross, Marina; Su, Zhe; Javitt, Daniel C; Butler, Pamela D

2014-11-01

340

Poisoning by organophosphorus insecticides and sensory neuropathy  

PubMed Central

OBJECTIVES—Poisoning by organophosphate insecticides causes cholinergic toxicity. Organophosphate induced delayed polyneuropathy (OPIDP) is a sensory-motor distal axonopathy which usually occurs after ingestion of large doses of certain organophosphate insecticides and has so far only been reported in patients with preceding cholinergic toxicity. Surprisingly, it was recently reported by other authors that an exclusively sensory neuropathy developed in eight patients after repeated unquantified exposures to chlorpyrifos, which did not cause clear-cut cholinergic toxicity. The objective was to assess whether an exclusively sensory neuropathy develops in patients severely poisoned by various OPs.?METHODS—Toxicological studies and electrophysiological measurements were performed in peripheral motor and sensory nerves in 11 patients after acute organophosphate poisoning among which two subjects were poisoned with chlorpyrifos.?RESULTS—Three patients developed OPIDP, including one poisoned by chlorpyrifos. Exclusively sensory neuropathy was never seen after either single or repeated acute organophosphate poisoning. A mild sensory component was associated with a severe motor component in two of the three cases of OPIDP, the other was an exclusively motor polyneuropathy.?CONCLUSION—A sensory-motor polyneuropathy caused by organophosphate insecticides might occur after a severe poisoning and the sensory component, if present, is milder than the motor one. Bearing in mind the toxicological characteristics of these organophosphate insecticides, other causes should be sought for sensory peripheral neuropathies in patients who did not display severe cholinergic toxicity a few weeks before the onset of symptoms and signs.?? PMID:9576536

Moretto, A.; Lotti, M.

1998-01-01

341

Exploring Sensory Integrative Treatment in Chronic Schizophrenia  

Microsoft Academic Search

An investigation of the efficacy of sensory integrative treatment of the psychiatric status and physical functioning of patients with chronic schizophrenia is reported. Patients were involved in sequenced sensory integrative treatment over a seventeen week period. Significant improvement was found in scores of the NOSIE-30 as well as on some of the usual idicators of sensory integrative status: thumb-finger opposition,

Judith E. Reisman; Anne B. Blakeney

1991-01-01

342

Functional and structural changes in the brain associated with the increase in muscle sympathetic nerve activity in obstructive sleep apnoea.  

PubMed

Muscle sympathetic nerve activity (MSNA) is greatly elevated in patients with obstructive sleep apnoea (OSA) during daytime wakefulness, leading to hypertension, but the underlying mechanisms are poorly understood. By recording MSNA concurrently with functional Magnetic Resonance Imaging (fMRI) of the brain we aimed to identify the central processes responsible for the sympathoexcitation. Spontaneous fluctuations in MSNA were recorded via tungsten microelectrodes inserted percutaneously into the common peroneal nerve in 17 OSA patients and 15 healthy controls lying in a 3 T MRI scanner. Blood Oxygen Level Dependent (BOLD) contrast gradient echo, echo-planar images were continuously collected in a 4 s ON, 4 s OFF (200 volumes) sampling protocol. Fluctuations in BOLD signal intensity covaried with the intensity of the concurrently recorded bursts of MSNA. In both groups there was a positive correlation between MSNA and signal intensity in the left and right insulae, dorsolateral prefrontal cortex (dlPFC), dorsal precuneus, sensorimotor cortex and posterior temporal cortex, and the right mid-cingulate cortex and hypothalamus. In OSA the left and right dlPFC, medial PFC (mPFC), dorsal precuneus, anterior cingulate cortex, retrosplenial cortex and caudate nucleus showed augmented signal changes compared with controls, while the right hippocampus/parahippocampus signal intensity decreased in controls but did not change in the OSA subjects. In addition, there were significant increases in grey matter volume in the left mid-insula, the right insula, left and right primary motor cortices, left premotor cortex, left hippocampus and within the brainstem and cerebellum, and significant decreases in the mPFC, occipital lobe, right posterior cingulate cortex, left cerebellar cortex and the left and right amygdala in OSA, but there was no overlap between these structural changes and the functional changes in OSA. These data suggest that the elevated muscle vasoconstrictor drive in OSA may result from functional changes within these brain regions, which are known to be directly or indirectly involved in the modulation of sympathetic outflow via the brainstem. That there was no overlap in the structural and functional changes suggests that asphyxic damage due to repeated episodes of nocturnal obstructive apnoea is not the main cause of the sympathoexcitation. PMID:25379440

Fatouleh, Rania H; Hammam, Elie; Lundblad, Linda C; Macey, Paul M; McKenzie, David K; Henderson, Luke A; Macefield, Vaughan G

2014-01-01

343

Functional and structural changes in the brain associated with the increase in muscle sympathetic nerve activity in obstructive sleep apnoea  

PubMed Central

Muscle sympathetic nerve activity (MSNA) is greatly elevated in patients with obstructive sleep apnoea (OSA) during daytime wakefulness, leading to hypertension, but the underlying mechanisms are poorly understood. By recording MSNA concurrently with functional Magnetic Resonance Imaging (fMRI) of the brain we aimed to identify the central processes responsible for the sympathoexcitation. Spontaneous fluctuations in MSNA were recorded via tungsten microelectrodes inserted percutaneously into the common peroneal nerve in 17 OSA patients and 15 healthy controls lying in a 3 T MRI scanner. Blood Oxygen Level Dependent (BOLD) contrast gradient echo, echo-planar images were continuously collected in a 4 s ON, 4 s OFF (200 volumes) sampling protocol. Fluctuations in BOLD signal intensity covaried with the intensity of the concurrently recorded bursts of MSNA. In both groups there was a positive correlation between MSNA and signal intensity in the left and right insulae, dorsolateral prefrontal cortex (dlPFC), dorsal precuneus, sensorimotor cortex and posterior temporal cortex, and the right mid-cingulate cortex and hypothalamus. In OSA the left and right dlPFC, medial PFC (mPFC), dorsal precuneus, anterior cingulate cortex, retrosplenial cortex and caudate nucleus showed augmented signal changes compared with controls, while the right hippocampus/parahippocampus signal intensity decreased in controls but did not change in the OSA subjects. In addition, there were significant increases in grey matter volume in the left mid-insula, the right insula, left and right primary motor cortices, left premotor cortex, left hippocampus and within the brainstem and cerebellum, and significant decreases in the mPFC, occipital lobe, right posterior cingulate cortex, left cerebellar cortex and the left and right amygdala in OSA, but there was no overlap between these structural changes and the functional changes in OSA. These data suggest that the elevated muscle vasoconstrictor drive in OSA may result from functional changes within these brain regions, which are known to be directly or indirectly involved in the modulation of sympathetic outflow via the brainstem. That there was no overlap in the structural and functional changes suggests that asphyxic damage due to repeated episodes of nocturnal obstructive apnoea is not the main cause of the sympathoexcitation. PMID:25379440

Fatouleh, Rania H.; Hammam, Elie; Lundblad, Linda C.; Macey, Paul M.; McKenzie, David K.; Henderson, Luke A.; Macefield, Vaughan G.

2014-01-01

344

White matter changes linked to visual recovery after nerve decompression  

PubMed Central

The relationship between the integrity of white matter tracts and cortical function in the human brain remains poorly understood. Here we use a model of reversible white matter injury, compression of the optic chiasm by tumors of the pituitary gland, to study the structural and functional changes that attend spontaneous recovery of cortical function and visual abilities after surgical tumor removal and subsequent decompression of the nerves. We show that compression of the optic chiasm leads to demyelination of the optic tracts, which reverses as quickly as 4 weeks after nerve decompression. Furthermore, variability across patients in the severity of demyelination in the optic tracts predicts visual ability and functional activity in early cortical visual areas, and pre-operative measurements of myelination in the optic tracts predicts the magnitude of visual recovery after surgery. These data indicate that rapid regeneration of myelin in the human brain is a significant component of the normalization of cortical activity, and ultimately the recovery of sensory and cognitive function, after nerve decompression. More generally, our findings demonstrate the utility of diffusion tensor imaging as an in vivo measure of myelination in the human brain. PMID:25504884

Paul, David A.; Gaffin-Cahn, Elon; Hintz, Eric B.; Adeclat, Giscard J.; Zhu, Tong; Williams, Zoë R.; Vates, G. Edward; Mahon, Bradford Z.

2015-01-01

345

Cyclophosphamide-induced cystitis reduces ASIC channel but enhances TRPV1 receptor function in rat bladder sensory neurons  

PubMed Central

Using patch-clamp techniques, we studied the plasticity of acid-sensing ion channels (ASIC) and transient receptor potential V1 (TRPV1) channel function in dorsal root ganglia (DRG) neurons retrogradely labeled from the bladder. Saline (control) or cyclophosphamide (CYP) was given intraperitoneally on days 1, 3, and 5. On day 6, lumbosacral (LS, L6–S2) or thoracolumbar (TL, T13–L2) DRG were removed and dissociated. Bladders and bladder DRG neurons from CYP-treated rats showed signs of inflammation (greater myeloperoxidase activity; lower intramuscular wall pH) and increased size (whole cell capacitance), respectively, compared with controls. Most bladder neurons (>90%) responded to protons and capsaicin. Protons produced multiphasic currents with distinct kinetics, whereas capsaicin always triggered a sustained response. The TRPV1 receptor antagonist A-425619 abolished capsaicin-triggered currents and raised the threshold of heat-activated currents. Prolonged exposure to an acidic environment (pH range: 7.2 to 6.6) inhibited proton-evoked currents, potentiated the capsaicin-evoked current, and reduced the threshold of heat-activated currents in LS and TL bladder neurons. CYP treatment reduced density but not kinetics of all current components triggered by pH 5. In contrast, CYP-treatment was associated with an increased current density in response to capsaicin in LS and TL bladder neurons. Correspondingly, heat triggered current at a significantly lower temperature in bladder neurons from CYP-treated rats compared with controls. These results reveal that cystitis differentially affects TRPV1- and ASIC-mediated currents in both bladder sensory pathways. Acidification of the bladder wall during inflammation may contribute to changes in nociceptive transmission mediated through the TRPV1 receptor, suggesting a role for TRPV1 in hypersensitivity associated with cystitis. PMID:23636721

Dang, Khoa; Bielefeldt, Klaus

2013-01-01

346

Mitochondrial abnormality in sensory, but not motor, axons in paclitaxel-evoked painful peripheral neuropathy in the rat  

PubMed Central

The dose-limiting side effect of the anti-neoplastic agent, paclitaxel, is a chronic distal symmetrical peripheral neuropathy that produces sensory dysfunction (hypoesthesia and neuropathic pain) but little or no distal motor dysfunction. Similar peripheral neuropathies are seen with chemotherapeutics in the vinca alkaloid, platinum-complex, and proteasome inhibitor classes. Studies in rats suggest that the cause is a mitotoxic effect on axonal mitochondria. If so, then the absence of motor dysfunction may be due to mitotoxicity that affects sensory axons but spares motor axons. To investigate this, paclitaxel exposure levels in the dorsal root, ventral root, dorsal root ganglion, peripheral nerve, and spinal cord were measured, and the ultrastructure and the respiratory function of mitochondria in dorsal roots and ventral roots were compared. Sensory and motor axons in the roots and nerve had comparably low exposure to paclitaxel and exposure in the spinal cord was negligible. However, sensory neurons in the dorsal root ganglion had a very high and remarkably persistent (up to10 days or more after the last injection) exposure to paclitaxel. Paclitaxel evoked a significant increase in the incidence of swollen and vacuolated mitochondria in the myelinated and unmyelinated sensory axons of the dorsal root (as seen previously in the peripheral nerve) but not in the motor axons of the ventral root. Stimulated mitochondrial respiration in the dorsal root was significantly depressed in paclitaxel-treated animals examined 2-4 weeks after the last injection, whereas respiration in the ventral root was normal. We conclude that the absence of motor dysfunction in paclitaxel-evoked peripheral neuropathy may be due to the absence of a mitotoxic effect in motor neuron axons, while the sensory dysfunction may be due to a mitotoxic effect resulting from the primary afferent neuron's cell body being exposed to high and persistent levels of paclitaxel. PMID:22037390

Xiao, Wen Hua; Zheng, Huaien; Zheng, Felix Y.; Nuydens, Rony; Meert, Theo F.; Bennett, Gary J.

2011-01-01

347

Expression profiling and Ingenuity biological function analyses of interleukin-6- versus nerve growth factor-stimulated PC12 cells  

PubMed Central

Background The major goal of the study was to compare the genetic programs utilized by the neuropoietic cytokine Interleukin-6 (IL-6) and the neurotrophin (NT) Nerve Growth Factor (NGF) for neuronal differentiation. Results The designer cytokine Hyper-IL-6 in which IL-6 is covalently linked to its soluble receptor s-IL-6R as well as NGF were used to stimulate PC12 cells for 24 hours. Changes in gene expression levels were monitored using Affymetrix GeneChip technology. We found different expression for 130 genes in IL-6- and 102 genes in NGF-treated PC12 cells as compared to unstimulated controls. The gene set shared by both stimuli comprises only 16 genes. A key step is upregulation of growth factors and functionally related external molecules known to play important roles in neuronal differentiation. In particular, IL-6 enhances gene expression of regenerating islet-derived 3 alpha (REG3A; 1084-fold), regenerating islet-derived 3 beta (REG3B/PAPI; 672-fold), growth differentiation factor 15 (GDF15; 80-fold), platelet-derived growth factor alpha (PDGFA; 69-fold), growth hormone releasing hormone (GHRH; 30-fold), adenylate cyclase activating polypeptide (PACAP; 20-fold) and hepatocyte growth factor (HGF; 5-fold). NGF recruits GDF15 (131-fold), transforming growth factor beta 1 (TGFB1; 101-fold) and brain-derived neurotrophic factor (BDNF; 89-fold). Both stimuli activate growth-associated protein 43 (GAP-43) indicating that PC12 cells undergo substantial neuronal differentiation. Moreover, IL-6 activates the transcription factors retinoic acid receptor alpha (RARA; 20-fold) and early growth response 1 (Egr1/Zif268; 3-fold) known to play key roles in neuronal differentiation. Ingenuity biological function analysis revealed that completely different repertoires of molecules are recruited to exert the same biological functions in neuronal differentiation. Major sub-categories include cellular growth and differentiation, cell migration, chemotaxis, cell adhesion, small molecule biochemistry aiming at changing intracellular concentrations of second messengers such as Ca2+ and cAMP as well as expression of enzymes involved in posttranslational modification of proteins. Conclusion The current data provide novel candidate genes involved in neuronal differentiation, notably for the neuropoietic cytokine IL-6. Our findings may also have impact on the clinical treatment of peripheral nerve injury. Local application of a designer cytokine such as H-IL-6 with drastically enhanced bioactivity in combination with NTs may generate a potent reparative microenvironment. PMID:19239705

Kunz, Dieter; Walker, Gaby; Bedoucha, Marc; Certa, Ulrich; März-Weiss, Pia; Dimitriades-Schmutz, Beatrice; Otten, Uwe

2009-01-01

348

Bladder function - neurological control  

MedlinePLUS Videos and Cool Tools

... with urine, sensory nerves send impulses to the brain indicating that the bladder is full. The sensory ... cord to relay this information. In turn, the brain sends impulses back to the bladder instructing the ...

349

The consistent presence of the human accessory deep peroneal nerve  

PubMed Central

Twenty-four human legs were dissected macroscopically to study the morphological details of the accessory deep peroneal nerve. This nerve arose from the superficial peroneal nerve and descended in the lateral compartment of the leg, deep to peroneus longus along the posterior border of peroneus brevis. Approaching the ankle joint, this nerve passed through the peroneal tunnels to wind around the lateral malleolus; it then crossed beneath the peroneus brevis tendon anteriorly to reach the dorsum of the foot. The accessory deep peroneal nerve was found in every case examined and constantly gave off muscular branches to peroneus brevis and sensory branches to the ankle region. In addition, this nerve occasionally had muscular branches to peroneus longus and extensor digitorum brevis, and sensory branches to the fibula and the foot. The anomalous muscles around the lateral malleolus were also innervated by this nerve. Neither cutaneous branches nor communicating branches with other nerves were found. The present study reveals that the accessory deep peroneal nerve is consistently present and possesses a proper motor and sensory distribution in the lateral region of the leg and ankle. It is not an anomalous nerve as has previously been suggested. PMID:10227671

KUDOH, HIROYUKI; SAKAI, TATSUO; HORIGUCHI, MASAHARU

1999-01-01

350

Localization and control of activity in peripheral nerves.  

PubMed

Interest in the field of the natural control of human limb using physiological signals has risen dramatically in the past 20 years due to the success of the brain machine interface. Cortical signals carry significant information but are difficult to access. The peripheral nerves of the body carry both command and sensory signals and are far more accessible. While numerous studies have documented the selective stimulation properties of, conventionally round, nerve cuff electrodes (i.e., transverse geometry) and even self-sizing electrodes, recording the activity levels from individual fascicles using these electrodes is still an unsolved problem. Moreover, the control algorithms for the control of joint movement with multiple contact electrodes such as the flat interface nerve electrode (FINE) have been difficult to implement. We propose solutions to both these problems by using beam forming techniques to detect the location and the activity in various fascicles. We also developed a control algorithm that separates the dynamic from the passive properties to solve the redundancy problem in multiple joint problems. This techniques could find application in the natural control of artificial limbs from peripheral nerve signals for patients with amputated limbs or to restore function in patients with stroke or paralyzed limbs. PMID:19163426

Durand, D M; Park, H J; Wodlinger, B

2008-01-01

351

Sciatic nerve regeneration induced by transplantation of in vitro bone marrow stromal cells into an inside-out artery graft in rat.  

PubMed

Traumatic injury to peripheral nerves results in considerable motor and sensory disability. Several research groups have tried to improve the regeneration of traumatized nerves by invention of favorable microsurgery. Effect of undifferentiated bone marrow stromal cells (BMSCs) combined with artery graft on peripheral nerve regeneration was studied using a rat sciatic nerve regeneration model. A 10-mm sciatic nerve defect was bridged using an artery graft (IOAG) filled with undifferentiated BMSCs (2 × 10(7) cells/mL). In control group, the graft was filled with phosphated buffer saline alone. The regenerated fibers were studied 4, 8 and 12 weeks after surgery. Assessment of nerve regeneration was based on behavioral, functional (Walking Track Analysis), electrophysiological, histomorphometric and immuohistochemical (Schwann cell detection by S-100 expression) criteria. The behavioral, functional and electrophysiological studies confirmed significant recovery of regenerated axons in IOAG/BMSC group (P < 0.05). Quantitative morphometric analyses of regenerated fibers showed the number and diameter of myelinated fibers in IOAG/BMSC group were significantly higher than in the control group (P < 0.05). This demonstrates the potential of using undifferentiated BMSCs combined with artery graft in peripheral nerve regeneration without limitations of donor-site morbidity associated with isolation of Schwann cells. It is also cost saving due to reduction in interval from tissue collection until cell injection, simplicity of laboratory procedures compared to differentiated BMSCs and may have clinical implications for the surgical management of patients after facial nerve transection. PMID:24942097

Mohammadi, Rahim; Vahabzadeh, Behnam; Amini, Keyvan

2014-10-01

352

Long-term sensory stimulation therapy improves hand function and restores cortical responsiveness in patients with chronic cerebral lesions. Three single case studies  

PubMed Central

Rehabilitation of sensorimotor impairment resulting from cerebral lesion (CL) utilizes task specific training and massed practice to drive reorganization and sensorimotor improvement due to induction of neuroplasticity mechanisms. Loss of sensory abilities often complicates recovery, and thus the individual's ability to use the affected body part for functional tasks. Therefore, the development of additional and alternative approaches that supplement, enhance, or even replace conventional training procedures would be advantageous. Repetitive sensory stimulation protocols (rSS) have been shown to evoke sensorimotor improvements of the affected limb in patients with chronic stroke. However, the possible impact of long-term rSS on sensorimotor performance of patients with CL, where the incident dated back many years remains unclear. The particular advantage of rSS is its passive nature, which does not require active participation of the subjects. Therefore, rSS can be applied in parallel to other occupations, making the intervention easier to implement and more acceptable to the individual. Here we report the effects of applying rSS for 8, 36, and 76 weeks to the paretic hand of three long-term patients with different types of CL. Different behavioral tests were used to assess sensory and/or sensorimotor performance of the upper extremities prior, after, and during the intervention. In one patient, the impact of long-term rSS on restoration of cortical activation was investigated by recording somatosensory evoked potentials (SEP). After long-term rSS all three patients showed considerable improvements of their sensory and motor abilities. In addition, almost normal evoked potentials could be recorded after rSS in one patient. Our data show that long-term rSS applied to patients with chronic CL can improve tactile and sensorimotor functions, which, however, developed in some cases only after many weeks of stimulation, and continued to further improve on a time scale of months. PMID:22936907

Kattenstroth, Jan-Christoph; Kalisch, Tobias; Peters, Sören; Tegenthoff, Martin; Dinse, Hubert R.

2012-01-01

353

A new sensory organ in “primitive” molluscs (Polyplacophora: Lepidopleurida), and its context in the nervous system of chitons  

PubMed Central

Introduction Chitons (Polyplacophora) are molluscs considered to have a simple nervous system without cephalisation. The position of the class within Mollusca is the topic of extensive debate and neuroanatomical characters can provide new sources of phylogenetic data as well as insights into the fundamental biology of the organisms. We report a new discrete anterior sensory structure in chitons, occurring throughout Lepidopleurida, the order of living chitons that retains plesiomorphic characteristics. Results The novel “Schwabe organ” is clearly visible on living animals as a pair of streaks of brown or purplish pigment on the roof of the pallial cavity, lateral to or partly covered by the mouth lappets. We describe the histology and ultrastructure of the anterior nervous system, including the Schwabe organ, in two lepidopleuran chitons using light and electron microscopy. The oesophageal nerve ring is greatly enlarged and displays ganglionic structure, with the neuropil surrounded by neural somata. The Schwabe organ is innervated by the lateral nerve cord, and dense bundles of nerve fibres running through the Schwabe organ epithelium are frequently surrounded by the pigment granules which characterise the organ. Basal cells projecting to the epithelial surface and cells bearing a large number of ciliary structures may be indicative of sensory function. The Schwabe organ is present in all genera within Lepidopleurida (and absent throughout Chitonida) and represents a novel anatomical synapomorphy of the clade. Conclusions The Schwabe organ is a pigmented sensory organ, found on the ventral surface of deep-sea and shallow water chitons; although its anatomy is well understood, its function remains unknown. The anterior commissure of the chiton oesophagial nerve ring can be considered a brain. Our thorough review of the chiton central nervous system, and particularly the sensory organs of the pallial cavity, provides a context to interpret neuroanatomical homology and assess this new sense organ. PMID:24447393

2014-01-01

354

Laryngopharyngeal sensory discrimination testing and the laryngeal adductor reflex.  

PubMed

Laryngopharyngeal sensory capacity has been determined by endoscopically administering air pulse stimuli to the mucosa innervated by the superior laryngeal nerve and asking the patient if he or she feels the stimulus. A potential shortcoming of this psychophysical testing (PT) procedure is that it is a subjective test, and patients with impaired cognition may not be able to perform the required task. In the search for an objective measure of laryngeal sensory function, we have observed that the laryngeal adductor reflex (LAR) is evoked at stimulus intensities similar to those capable of eliciting the psychophysical, or perceptual, response. The purpose of this study is to determine if the threshold for eliciting the LAR is the same as that of the sensory threshold. A specially designed endoscope was used to present air pulse stimuli (range 0.0 to 10 mm Hg) to the laryngopharynx in 20 healthy subjects and in 80 patients with dysphagia, using both PT and the LAR. The patients had a variety of underlying diagnoses, with stroke and chronic neurologic disease predominating (n = 65). In the control group and in the group of patients with dysphagia, there was no statistically significant difference between the median laryngopharyngeal sensory thresholds whether we used PT or the LAR (p>.05, Wilcoxon signed-rank test). The intraclass correlation for the total sample was .999 (U = .999, L = .998). Since psychophysical and sensorimotor reflex thresholds were not statistically significantly different and the intraclass correlation was close to a perfect correlation, we conclude that the LAR can be used as an objective and accurate clinical method of endoscopically assessing laryngopharyngeal sensory capacity. PMID:10453777

Aviv, J E; Martin, J H; Kim, T; Sacco, R L; Thomson, J E; Diamond, B; Close, L G

1999-08-01

355

The MMP-9/TIMP-1 Axis Controls the Status of Differentiation and Function of Myelin-Forming Schwann Cells in Nerve Regeneration  

PubMed Central

Background Myelinating Schwann cells (mSCs) form myelin in the peripheral nervous system. Because of the works by us and others, matrix metalloproteinase-9 (MMP-9) has recently emerged as an essential component of the Schwann cell signaling network during sciatic nerve regeneration. Methodology/Principal Findings In the present study, using the genome-wide transcriptional profiling of normal and injured sciatic nerves in mice followed by extensive bioinformatics analyses of the data, we determined that an endogenous, specific MMP-9 inhibitor [tissue inhibitor of metalloproteinases (TIMP)-1] was a top up-regulated gene in the injured nerve. MMP-9 capture followed by gelatin zymography and Western blotting of the isolated samples revealed the presence of the MMP-9/TIMP-1 heterodimers and the activated MMP-9 enzyme in the injured nerve within the first 24 h post-injury. MMP-9 and TIMP-1 co-localized in mSCs. Knockout of the MMP-9 gene in mice resulted in elevated numbers of de-differentiated/immature mSCs in the damaged nerve. Our comparative studies using MMP-9 knockout and wild-type mice documented an aberrantly enhanced proliferative activity and, accordingly, an increased number of post-mitotic Schwann cells, short internodes and additional nodal abnormalities in remyelinated nerves of MMP-9 knockout mice. These data imply that during the first days post-injury MMP-9 exhibits a functionally important anti-mitogenic activity in the wild-type mice. Pharmacological inhibition of MMP activity suppressed the expression of Nav1.7/1.8 channels in the crushed nerves. Conclusion/Significance Collectively, our data established an essential role of the MMP-9/TIMP-1 axis in guiding the mSC differentiation and the molecular assembly of myelin domains in the course of the nerve repair process. Our findings of the MMP-dependent regulation of Nav channels, which we document here for the first time, provide a basis for therapeutic intervention in sensorimotor pathologies and pain. PMID:22438979

Kim, Youngsoon; Remacle, Albert G.; Chernov, Andrei V.; Liu, Huaqing; Shubayev, Igor; Lai, Calvin; Dolkas, Jennifer; Shiryaev, Sergey A.; Golubkov, Vladislav S.; Mizisin, Andrew P.; Strongin, Alex Y.; Shubayev, Veronica I.

2012-01-01

356

Nanofibrous nerve conduit-enhanced peripheral nerve regeneration.  

PubMed

Fibre structures represent a potential class of materials for the formation of synthetic nerve conduits due to their biomimicking architecture. Although the advantages of fibres in enhancing nerve regeneration have been demonstrated, in vivo evaluation of fibre size effect on nerve regeneration remains limited. In this study, we analyzed the effects of fibre diameter of electrospun conduits on peripheral nerve regeneration across a 15-mm critical defect gap in a rat sciatic nerve injury model. By using an electrospinning technique, fibrous conduits comprised of aligned electrospun poly (?-caprolactone) (PCL) microfibers (981?±?83 nm, Microfiber) or nanofibers (251?±?32 nm, Nanofiber) were obtained. At three months post implantation, axons regenerated across the defect gap in all animals that received fibrous conduits. In contrast, complete nerve regeneration was not observed in the control group that received empty, non-porous PCL film conduits (Film). Nanofiber conduits resulted in significantly higher total number of myelinated axons and thicker myelin sheaths compared to Microfiber and Film conduits. Retrograde labeling revealed a significant increase in number of regenerated dorsal root ganglion sensory neurons in the presence of Nanofiber conduits (1.93 ± 0.71 × 10(3) vs. 0.98 ± 0.30 × 10(3) in Microfiber, p?nerve regeneration. These results could provide useful insights for future nerve guide designs. PMID:22700359

Jiang, Xu; Mi, Ruifa; Hoke, Ahmet; Chew, Sing Yian

2014-05-01

357

Nerve conduction  

MedlinePLUS Videos and Cool Tools

... fibers (neurons). Neurons consist of dendrites, axon, and cell body. The dendrites are the tree-like structures ... signals from other neurons and from special sensory cells that sense the body’s surrounding environment. The cell ...

358

Anatomy of the rat knee joint and fibre composition of a major articular nerve.  

PubMed

Several recent reports discuss the role of joint nerves in arthritis. Many of these are based on studies in the rat. The aim of this study is to examine the anatomy of the rat knee joint, in search for a primary articular nerve, and to analyze the fibre composition of that nerve. The results show that the structure of the joint differs in some respects from the human knee. At the upper end of the bony patella a cartilaginous patella extends proximally, forming the anterior wall of the suprapatellar bursa. Distinct collateral ligaments are integrated in the joint capsule. The extensor digitorum longus muscle bridges the knee joint, originating from the lateral femoral epicondyle. The well-developed menisci contain pyramid-shaped ossicles. The cruciate ligaments are arranged like in the human knee. A large posterior (PAN) and a small medial (MAN) articular nerve can be identified. The PAN is composed of some 400 axons, about 80% of which are unmyelinated. All myelinated fibres are sensory. They present a unimodal size spectrum with a size range of 1-8 microns, and a predominance of small fibres. Specific denervations indicate that about 1/3 of the unmyelinated axons represent afferents, and some 2/3 are sympathetic efferents. Interestingly, neonatal capsaicin treatment did not influence the number of unmyelinated PAN axons. The functional significance of the numerous unmyelinated sympathetic and sensory PAN axons in the normal knee joint remains to be elucidated. PMID:2048758

Hildebrand, C; Oqvist, G; Brax, L; Tuisku, F

1991-04-01

359

Peripheral nerve repair with nerve growth factor and fibrin matrix  

Microsoft Academic Search

A fibrin sealant matrix (FS) with or without a nerve growth factor (NGF) has been used to improve the recovery of severed peripheral nerves, and these have been compared with the results of using only the standard epineural suture (SUT). Regeneration in the early phase (up to 6 days) was measured by the pinch test. The functional recovery process (up

L. Zeng; A. Worseg; H. Redl; G. Schlag

1994-01-01

360

Laser microirradiation in the investigation of the integrative function of nerve cells  

NASA Astrophysics Data System (ADS)

We attempted to selectively affect mitochondria by a laser microbeam along with parallel investigations of neuron structural and functional changes and modifications of neuron responses with supravital stains, bioenergetic inhibitors, various calcium concentrations in the saline, etc. Experimental data indicate that transient inhibition phase owing to selective laser influence on mitochondria are superimposed on neuron excitation caused by laser action on neuronal membrane.

Uzdensky, Anatoly B.

1994-02-01

361

Irreversible muscle contracture after functioning free muscle transplantation using the ipsilateral facial nerve for reinnervation  

Microsoft Academic Search

Four patients who underwent functioning free muscle transplantation (FFMT) for facial reconstruction developed a progressive disfiguring muscle contracture. This complication has not been previously reported. Three of the patients had longstanding facial paralysis and were reanimated by FFMT. The fourth patient had left hemifacial atrophy but without facial paralysis. She also underwent FFMT for augmentation. All four FFMTs were innervated

Vikram S. Deveraj; F WEI

1995-01-01

362

What Are You Feeling? Using Functional Magnetic Resonance Imaging to Assess the Modulation of Sensory and Affective Responses during Empathy for Pain  

PubMed Central

Background Recent neuroscientific evidence suggests that empathy for pain activates similar neural representations as the first-hand experience of pain. However, empathy is not an all-or-none phenomenon but it is strongly malleable by interpersonal, intrapersonal and situational factors. This study investigated how two different top-down mechanisms – attention and cognitive appraisal - affect the perception of pain in others and its neural underpinnings. Methodology/Principal Findings We performed one behavioral (N?=?23) and two functional magnetic resonance imaging (fMRI) experiments (N?=?18). In the first fMRI experiment, participants watched photographs displaying painful needle injections, and were asked to evaluate either the sensory or the affective consequences of these injections. The role of cognitive appraisal was examined in a second fMRI experiment in which participants watched injections that only appeared to be painful as they were performed on an anesthetized hand. Perceiving pain in others activated the affective-motivational and sensory-discriminative aspects of the pain matrix. Activity in the somatosensory areas was specifically enhanced when participants evaluated the sensory consequences of pain. Perceiving non-painful injections into the anesthetized hand also led to signal increase in large parts of the pain matrix, suggesting an automatic affective response to the putatively harmful stimulus. This automatic response was modulated by areas involved in self/other distinction and valence attribution – including the temporo-parietal junction and medial orbitofrontal cortex. Conclusions/Significance Our findings elucidate how top-down control mechanisms and automatic bottom-up processes interact to generate and modulate other-oriented responses. They stress the role of cognitive processing in empathy, and shed light on how emotional and bodily awareness enable us to evaluate the sensory and affective states of others. PMID:18091986

Lamm, Claus; Nusbaum, Howard C.; Meltzoff, Andrew N.; Decety, Jean

2007-01-01

363

Alignment and composition of laminin–polycaprolactone nanofiber blends enhance peripheral nerve regeneration  

PubMed Central

Peripheral nerve transection occurs commonly in traumatic injury, causing deficits distal to the injury site. Conduits for repair currently on the market are hollow tubes; however, they often fail due to slow regeneration over long gaps. To facilitate increased regeneration speed and functional recovery, the ideal conduit should provide biochemically relevant signals and physical guidance cues, thus playing an active role in regeneration. To that end, laminin and laminin–polycaprolactone (PCL) blend nanofibers were fabricated to mimic peripheral nerve basement membrane. In vitro assays established 10% (wt) laminin content is sufficient to retain neurite-promoting effects of laminin. In addition, modified collector plate design to introduce an insulating gap enabled the fabrication of aligned nanofibers. The effects of laminin content and fiber orientation were evaluated in rat tibial nerve defect model. The lumens of conduits were filled with nanofiber meshes of varying laminin content and alignment to assess changes in motor and sensory recovery. Retrograde nerve conduction speed at 6 weeks was significantly faster in animals receiving aligned nanofiber conduits than in those receiving random nanofiber conduits. Animals receiving nanofiber-filled conduits showed some conduction in both anterograde and retrograde directions, whereas in animals receiving hollow conduits, no impulse conduction was detected. Aligned PCL nanofibers significantly improved motor function; aligned laminin blend nanofibers yielded the best sensory function recovery. In both cases, nanofiber-filled conduits resulted in better functional recovery than hollow conduits. These studies provide a firm foundation for the use of natural–synthetic blend electrospun nanofibers to enhance existing hollow nerve guidance conduits. PMID:22106069

Neal, Rebekah A.; Tholpady, Sunil S.; Foley, Patricia L.; Swami, Nathan; Ogle, Roy C.; Botchwey, Edward A.

2012-01-01

364

Nerve Injury Increases GluA2-Lacking AMPA Receptor Prevalence in Spinal Cords: Functional Significance and Signaling Mechanisms  

PubMed Central

The glutamate ?-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) are critically involved in the excitatory synaptic transmission, and blocking AMPARs at the spinal level reverses neuropathic pain. However, little is known about changes in the composition of synaptic AMPARs in the spinal dorsal horn after peripheral nerve injury. AMPARs lacking the GluA2 subunit are permeable to Ca2+, and their currents show unique inward rectification. We found that AMPAR-mediated excitatory postsynaptic currents (AMPAR-EPSCs) of spinal dorsal horn neurons exhibited a linear current-voltage relationship in control rats, whereas AMPAR-EPSCs of dorsal horn neurons displayed inward rectification in rats with spinal nerve injury. In nerve-injured rats, compared with control rats, the GluA2 protein level was significantly less in the plasma membrane but was greater in the cytosolic vesicle fraction in the dorsal spinal cord. However, the GluA1 protein levels in these fractions did not differ significantly between nerve-injured and control rats. Blocking N-methyl-d-aspartate receptors (NMDARs) abolished inward rectification of AMPAR-EPSCs of dorsal horn neurons in nerve-injured rats. Furthermore, inhibition of calpain or calcineurin, but not protein kinase C, completely blocked nerve injury–induced inward rectification of AMPAR-EPSCs of dorsal horn neurons. In addition, blocking GluA2-lacking AMPARs at the spinal cord level reduced nerve injury–induced pain hypersensitivity. Our study suggests that nerve injury increases GluA2 internalization and the prevalence of GluA2-lacking AMPARs in the spinal dorsal horn to maintain chronic neuropathic pain. Increased prevalence of spinal GluA2-lacking AMPARs in neuropathic pain is mediated by NMDARs and subsequent stimulation of calpain and calcineurin signaling. PMID:24030012

Chen, Shao-Rui; Zhou, Hong-Yi; Byun, Hee Sun

2013-01-01

365

Effects of extracorporeal shock wave therapy on functional recovery and neurotrophin-3 expression in the spinal cord after crushed sciatic nerve injury in rats.  

PubMed

The study described here investigated the effects of extracorporeal shock wave therapy (ESWT) on functional recovery and neurotrophin-3 expression in the spinal cord after sciatic nerve injury in rats. Forty-five 8-wk-old rats were used and randomly divided into three groups: An experimental group, a control group and a sham group. The experimental group received ESWT after the nerve-crushing damage. The sciatic functional index and Dartfish Software were used to determine the effect of sciatic nerve damage on functional changes. A 1-cm length of spinal cord encompassing the L4-6 level was removed for Western blot analysis. The sciatic functional index significantly changed in both the ESWT and control groups after impairment. In the time course evaluation of the ankle angle in the toe off, the ESWT group had statistically significant increases from day 21 onward. There was a significant difference in neurotrophin-3 expression between the groups on days 1, 7 and 14 after impairment. Early application of ESWT increased the expression of neurotrophin-3 and neurotrophin-3 mRNA, and daily therapy facilitated the activity of macrophages and Schwann cells, which affect the survival and regeneration of neurons. PMID:25619787

Lee, Jung-Ho; Kim, Seong-Gil

2015-03-01

366

Peptide regulators of peripheral taste function  

PubMed Central

The peripheral sensory organ of the gustatory system, the taste bud, contains a heterogeneous collection of sensory cells. These taste cells can differ in the stimuli to which they respond and the receptors and other signaling molecules they employ to transduce and encode gustatory stimuli. This molecular diversity extends to the expression of a varied repertoire of bioactive peptides that appear to play important functional roles in signaling taste information between the taste cells and afferent sensory nerves and/or in processing sensory signals within the taste bud itself. Here, we review studies that examine the expression of bioactive peptides in the taste bud and the impact of those peptides on taste functions. Many of these peptides produced in taste buds are known to affect appetite, satiety or metabolism through their actions in the brain, pancreas and other organs, suggesting a functional link between the gustatory system and the neural and endocrine systems that regulate feeding and nutrient utilization. PMID:23348523

Dotson, Cedrick D.; Geraedts, Maartje C.P.; Munger, Steven D.

2013-01-01

367

Peptide regulators of peripheral taste function.  

PubMed

The peripheral sensory organ of the gustatory system, the taste bud, contains a heterogeneous collection of sensory cells. These taste cells can differ in the stimuli to which they respond and the receptors and other signaling molecules they employ to transduce and encode those stimuli. This molecular diversity extends to the expression of a varied repertoire of bioactive peptides that appear to play important functional roles in signaling taste information between the taste cells and afferent sensory nerves and/or in processing sensory signals within the taste bud itself. Here, we review studies that examine the expression of bioactive peptides in the taste bud and the impact of those peptides on taste functions. Many of these peptides produced in taste buds are known to affect appetite, satiety or metabolism through their actions in the brain, pancreas and other organs, suggesting a functional link between the gustatory system and the neural and endocrine systems that regulate feeding and nutrient utilization. PMID:23348523

Dotson, Cedrick D; Geraedts, Maartje C P; Munger, Steven D

2013-03-01

368

Vitamin D Insufficiency is Associated with Reduced Parasympathetic Nerve Fiber Function in Type 2 Diabetes.  

PubMed

Objective: Vitamin D insufficiency is prevalent in type 2 diabetes mellitus (T2DM) and is associated with peripheral neuropathy. There is little data, however, for cardiovascular autonomic neuropathy. Our objective was to evaluate the association of cardiovascular autonomic function, 25-hydroxyvitamin D (25(OH)D) insufficiency (i.e., levels >30 ng/mL), and multiple metabolic parameters in T2DM.Methods: We examined 50 individuals with T2DM. Cardiovascular autonomic function was assessed by RR-variation during deep breathing (i.e., mean circular resultant (MCR), expiration/inspiration (E/I) ratio). These measures assess parasympathetic function. Metabolic parameters included measures of adiposity, glycemic control, insulin resistance, calcium metabolism and 25(OH)D.Results: Participants with 25(OH)D insufficiency (n=26) were younger (66±9 vs. 60±10 years, p>0.05), more insulin resistant, had a higher body mass index and lower adiponectin levels. The MCR (39.5±26.3 vs. 27.6±17.2, p>0.01) and E/I ratio (1.21±0.17 vs. 1.15±0.09, p>0.01) were lower for those with 25(OH)D insufficiency, after controlling for age. A stepwise selection procedure regressing MCR and E/I ratio on a number of metabolic parameters resulted in a model identifying age and 25(OH)D insufficiency as significant determinants for both measures. The interaction of age x 25(OH)D insufficiency was also included (MCR model, R2=0.491, p>0.001; E/I ratio, R2=0.455, p>0.001). Neither glycemic control nor other metabolic parameters were selected.Conclusion: Our results suggest that 25(OH)D insufficiency is associated with reduced parasympathetic function, the association being stronger in younger persons with T2DM. Studies are needed to determine if vitamin D supplementation into the sufficient range could prevent or delay the onset of cardiovascular autonomic dysfunction. PMID:25297669

Maser, Raelene E; Lenhard, M James; Pohlig, Ryan T

2014-10-01

369

Virtual Instrumentation for a Fiber-Optics-Based Artificial Nerve  

NASA Technical Reports Server (NTRS)

A LabView-based computer interface for fiber-optic artificial nerves has been devised as a Masters thesis project. This project involves the use of outputs from wavelength multiplexed optical fiber sensors (artificial nerves), which are capable of producing dense optical data outputs for physical measurements. The potential advantages of using optical fiber sensors for sensory function restoration is the fact that well defined WDM-modulated signals can be transmitted to and from the sensing region allowing networked units to replace low-level nerve functions for persons desirous of "intelligent artificial limbs." Various FO sensors can be designed with high sensitivity and the ability to be interfaced with a wide range of devices including miniature shielded electrical conversion units. Our Virtual Instrument (VI) interface software package was developed using LabView's "Laboratory Virtual Instrument Engineering Workbench" package. The virtual instrument has been configured to arrange and encode the data to develop an intelligent response in the form of encoded digitized signal outputs. The architectural layout of our nervous system is such that different touch stimuli from different artificial fiber-optic nerve points correspond to gratings of a distinct resonant wavelength and physical location along the optical fiber. Thus, when an automated, tunable diode laser sends scans, the wavelength spectrum of the artificial nerve, it triggers responses that are encoded with different touch stimuli by way wavelength shifts in the reflected Bragg resonances. The reflected light is detected and a resulting analog signal is fed into ADC1 board and DAQ card. Finally, the software has been written such that the experimenter is able to set the response range during data acquisition.

Lyons, Donald R.; Kyaw, Thet Mon; Griffin, DeVon (Technical Monitor)

2001-01-01

370

Lazzaro and Mead --Circuit Models of Sensory Transduction in the Cochlea CIRCUIT MODELS OF SENSORY TRANSDUCTION  

E-print Network

intensities to a manageable excursion of signal level. Spiral-ganglion neurons connect-nerve fiber can encode only about 25 dB of sound intensity. Humans can sense binaural time differences of Technology Pasadena, California, 91125 Nonlinear signal processing is an integral part of sensory