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Sample records for airway afferent nerve

  1. TRPM8 mechanism of autonomic nerve response to cold in respiratory airway

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    Wang Cong-Yi

    2008-06-01

    Full Text Available Abstract Breathing cold air without proper temperature exchange can induce strong respiratory autonomic responses including cough, airway constriction and mucosal secretion, and can exacerbate existing asthma conditions and even directly trigger an asthma attack. Vagal afferent fiber is thought to be involved in the cold-induced respiratory responses through autonomic nerve reflex. However, molecular mechanisms by which vagal afferent fibers are excited by cold remain unknown. Using retrograde labeling, immunostaining, calcium imaging, and electrophysiological recordings, here we show that a subpopulation of airway vagal afferent nerves express TRPM8 receptors and that activation of TRPM8 receptors by cold excites these airway autonomic nerves. Thus activation of TRPM8 receptors may provoke autonomic nerve reflex to increase airway resistance. This putative autonomic response may be associated with cold-induced exacerbation of asthma and other pulmonary disorders, making TRPM8 receptors a possible target for prevention of cold-associated respiratory disorders.

  2. The visceromotor and somatic afferent nerves of the penis.

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

    2015-05-01

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

  3. Role of nucleus retroambigualis in respiratory reflexes evoked by superior laryngeal and vestibular nerve afferents and in emesis.

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    Umezaki, T; Zheng, Y; Shiba, K; Miller, A D

    1997-09-26

    An ascending projection from the medullary nucleus retroambigualis (NRA) has recently been described as important for the control of the upper airway during vocalization. We evaluated the importance of this projection in other behaviors by making localized injections of the neurotoxin kainic acid in the NRA in decerebrate cats, most of which were paralyzed and artificially ventilated. In contrast to its importance for vocalization, the NRA is not essential for activation of upper airway musculature during respiration, swallowing, vomiting, or reflexes elicited by superior laryngeal or vestibular nerve afferents. However, kainic acid injections in the NRA and adjacent reticular formation prolonged the inhibitory phrenic motoneuronal response to superior laryngeal nerve stimulation and abolished or reduced abdominal motoneuronal responses during respiration, vomiting, and superior laryngeal nerve stimulation. Thus, of the behaviors we investigated, the importance of the ascending projection from the NRA appears to be limited to vocalization, while descending projections from the NRA region are important in a number of behaviors.

  4. The role of the renal afferent and efferent nerve fibers in heart failure

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    Booth, Lindsea C.; May, Clive N.; Yao, Song T.

    2015-01-01

    Renal nerves contain afferent, sensory and efferent, sympathetic nerve fibers. In heart failure (HF) there is an increase in renal sympathetic nerve activity (RSNA), which can lead to renal vasoconstriction, increased renin release and sodium retention. These changes are thought to contribute to renal dysfunction, which is predictive of poor outcome in patients with HF. In contrast, the role of the renal afferent nerves remains largely unexplored in HF. This is somewhat surprising as there are multiple triggers in HF that have the potential to increase afferent nerve activity, including increased venous pressure and reduced kidney perfusion. Some of the few studies investigating renal afferents in HF have suggested that at least the sympatho-inhibitory reno-renal reflex is blunted. In experimentally induced HF, renal denervation, both surgical and catheter-based, has been associated with some improvements in renal and cardiac function. It remains unknown whether the effects are due to removal of the efferent renal nerve fibers or afferent renal nerve fibers, or a combination of both. Here, we review the effects of HF on renal efferent and afferent nerve function and critically assess the latest evidence supporting renal denervation as a potential treatment in HF. PMID:26483699

  5. Imaging stretch-activated firing of spinal afferent nerve endings in mouse colon

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    Lee etravis

    2013-10-01

    Full Text Available Spinal afferent neurons play a major role in detecting noxious and innocuous stimuli from visceral organs, such as the gastrointestinal tract. However, all our understanding about spinal afferents has been obtained from recordings of spinal afferent axons, or cell bodies that lie outside the gut wall, or peripheral organ they innervate. No recordings have been made directly from spinal afferent nerve endings, which is where sensory transduction occurs. We developed a preparation whereby recordings could be made from rectal afferent nerve endings in the colon, to characterize mechanisms underlying sensory transduction. Dorsal root ganglia (L6-S2 were removed from mice, whilst retaining neural continuity with the colon. Fluo-4-AM was used to record from rectal afferent nerve endings in myenteric ganglia and circular muscle at 36oC. In slack (unstretched preparations of colon, no calcium transients were recorded from spinal afferent endings. However, in response to a maintained increase in circumferential diameter, a maintained discharge of calcium transients occurred simultaneously in multiple discrete varicosities along single axons of rectal afferents in myenteric ganglia and circular muscle. Stretch-activated calcium transients were resistant to hexamethonium and nifedipine, but were abolished by tetrodotoxin, CPA, BAPTA-AM, cobalt, gadolinium, or replacement of extracellular Na+ with NMDG. In summary, we present a novel preparation in which stretch-activated firing of spinal afferent nerve endings can be recorded, using calcium imaging. We show that circumferential stretch of the colon activates a maintained discharge of calcium transients simultaneously in varicosities along single rectal afferent endings in myenteric ganglia and circular muscle. Non-selective cation channels, TTX-sensitive Na+ channels and both extracellular calcium influx and intracellular Ca2+ stores are required for stretch-activated calcium transients in rectal afferent

  6. Effect of nicotine on the pelvic afferent nerve activity and bladder pressure in rats.

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    Kontani, Hitoshi; Okamura, Takashi; Kimura, Satoko; Ishida, Kazuumi; Takeno, Satoshi

    2009-08-01

    To record afferent nerve activity and bladder pressure in anesthetized male rats and to investigate whether increased afferent nerve activity induced by nicotine is able to evoke reflex bladder contractions. Using continuous infusion cystometrography, bladder pressure was measured via a bladder cannula. Afferent activity was recorded in the uncut L6 dorsal root. Nicotine was injected intra-arterially through a cannula placed near the bifurcation of the internal iliac artery a few minutes after micturition. Nicotine (0.15-1.5 micromol) evoked a marked elevation of afferent discharge without a simultaneous increase in bladder pressure. Bladder contractions appeared about 43 and 19 s after bolus injection of nicotine at 0.45 and 1.5 micromol, respectively. Firing rates of afferent nerves were reduced when the contraction appeared. Continuous infusion of nicotine at 0.75 micromol/min for 20 min evoked marked elevation of afferent discharge, which was maintained during infusion of nicotine and after it had been withdrawn. Repetitive contractions were observed thereafter and disappeared when the L6 dorsal roots were bilaterally resected. A transient increase in afferent discharges induced by bolus injection of nicotine was unable to evoke reflex bladder contraction. Repetitive bladder contractions after withdrawal of continuous nicotine infusion were induced in a reflex manner by the increased afferent activity.

  7. Vestibular afferents to the motoneurons of glossopharyngeal and vagus nerves in the frog, Rana esculenta.

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    Deák, Adám; Bácskai, Tímea; Veress, Gábor; Matesz, Clara

    2009-08-25

    The aim of this work was to study whether the vestibular afferent fibers establish direct connections with the motoneurons of glossopharyngeal and vagus nerves of the frog, Rana esculenta. In anaesthetized animals the vestibulocochlear nerve and the common root of glossopharyngeal-vagus and accessory (IX-X-XI) nerves were simultaneously labeled with fluorescein dextran amine (vestibulocochlear nerve) and tetramethylrhodamine dextran amine (IX-X-XI). With a confocal laser scanning microscope we could detect close appositions between the vestibular afferent fibers and somatodendritic components of the general and special visceral motoneurons of the ambiguus nucleus of IX-X nerves. The direct impulse transmission may provide a quick and immediate response of cardiovascular and gastrointestinal system upon body displacement.

  8. The renal nerves in chronic heart failure: efferent and afferent mechanisms

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    Schiller, Alicia M.; Pellegrino, Peter R.; Zucker, Irving H.

    2015-01-01

    The function of the renal nerves has been an area of scientific and medical interest for many years. The recent advent of a minimally invasive catheter-based method of renal denervation has renewed excitement in understanding the afferent and efferent actions of the renal nerves in multiple diseases. While hypertension has been the focus of much this work, less attention has been given to the role of the renal nerves in the development of chronic heart failure (CHF). Recent studies from our laboratory and those of others implicate an essential role for the renal nerves in the development and progression of CHF. Using a rabbit tachycardia model of CHF and surgical unilateral renal denervation, we provide evidence for both renal efferent and afferent mechanisms in the pathogenesis of CHF. Renal denervation prevented the decrease in renal blood flow observed in CHF while also preventing increases in Angiotensin-II receptor protein in the microvasculature of the renal cortex. Renal denervation in CHF also reduced physiological markers of autonomic dysfunction including an improvement in arterial baroreflex function, heart rate variability, and decreased resting cardiac sympathetic tone. Taken together, the renal sympathetic nerves are necessary in the pathogenesis of CHF via both efferent and afferent mechanisms. Additional investigation is warranted to fully understand the role of these nerves and their role as a therapeutic target in CHF. PMID:26300788

  9. Effect of chemical stimuli on nerves supplying upper airway muscles.

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    Weiner, D; Mitra, J; Salamone, J; Cherniack, N S

    1982-03-01

    Studies of upper airway resistance suggest that the activity of cranial nerves supplying upper airway muscles changes with chemical drive and that imbalances in the activation of these nerves as compared to the phrenic play a role in causing upper airway obstruction. We assessed the effect of hypoxia and hypercapnia on the activity of the hypoglossal nerve, the recurrent laryngeal nerve, and phrenic nerve in paralyzed anesthetized artificially ventilated dogs. Comparison of hypoglossal and phrenic nerves were also repeated after vagotomy. Both hypoglossal and recurrent laryngeal nerves exhibited increased activity with inspiration. Hypoxia and hypercapnia increased phrenic nerve activity as well as the activity of the two cranial nerves. While linear increases occurred in phrenic and recurrent laryngeal nerve activity with both chemical stimuli, the relationship between hypoglossal and phrenic nerve activity was curvilinear. At lower levels of chemical drive, changes in hypoglossal nerve were less than in the phrenic, and the reverse was true at higher levels of chemical stimulation. There were also differences in the response of both cranial nerves and the phrenic to changing vagal stimulation. The dissimilarities observed in the cranial response of the nerves (versus the phrenic) could potentially affect the forces developed during inspiration and lead to obstruction in the upper airway.

  10. The Renal Nerves in Chronic Heart Failure: Afferent and Efferent Mechanisms

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    Alicia Marie Schiller

    2015-08-01

    Full Text Available The function of the renal nerves has been an area of scientific and medical interest for many years. The recent advent of a minimally invasive catheter-based method of renal denervation has renewed excitement in understanding the afferent and efferent actions of the renal nerves in multiple diseases. While hypertension has been the focus of much this work, less attention has been given to the role of the renal nerves in the development of chronic heart failure (CHF. Recent studies from our laboratory and those of others implicate an essential role for the renal nerves in the development and progression of CHF. Using a rabbit tachycardia model of CHF and surgical unilateral renal denervation, we provide evidence for both renal efferent and afferent mechanisms in the pathogenesis of CHF. Renal denervation prevented the decrease in renal blood flow observed in CHF while also preventing increases in Angiotensin-II receptor protein in the microvasculature of the renal cortex. Renal denervation in CHF also reduced physiological markers of autonomic dysfunction including an improvement in arterial baroreflex function, heart rate variability, and decreased resting cardiac sympathetic tone. Taken together, the renal sympathetic nerves are necessary in the pathogenesis of CHF via both efferent and afferent

  11. Pulmonary Stress Induced by Hyperthermia: Role of Airway Sensory Nerves

    Science.gov (United States)

    2016-01-01

    sympathetic nerves via the white rami communicants to the spinal cord. The spe- cific role of these “sympathetic afferents” in the regulation of respiratory...subtypes and afferent properties Sympathetic sensory activity has been recorded in stellate ganglia (160) and white rami of T2 to T4 (198). This activity...Coleridge JC, Kidd C. Proceedings: Multi- terminal afferent fibres from the thoracic viscera in sympathetic rami communicantes of cats and dogs. J

  12. Visceral afferent activation-induced changes in sympathetic nerve activity and baroreflex sensitivity.

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    Saleh, T M; Connell, B J; Allen, G V

    1999-06-01

    The following experiments were done to determine whether changes in baroreflex sensitivity evoked by cervical vagus nerve stimulation are due to sympathoexcitation mediated by the parabrachial nucleus. The relative contribution of cardiopulmonary and general gastric afferents within the cervical vagus nerve to the depression in baroreflex sensitivity are also investigated. Male Sprague-Dawley rats anesthetized with thiobutabarbital sodium (50 mg/kg) were instrumented to measure blood pressure and heart rate or for the continuous monitoring of renal sympathetic nerve activity. Baroreflex sensitivity was measured using bolus injections of phenylephrine. Electrical stimulation of the cervical vagus (with or without the aortic depressor nerve) or the abdominal vagus nerve produced a significant increase in renal nerve activity and a decrease in baroreflex sensitivity. Both of these effects were blocked after the microinjection of lidocaine into the parabrachial nucleus before nerve stimulation. Therefore, we conclude that an increase in the activity of cardiac, pulmonary, or general gastric afferents mediated the increased sympathetic output and decreased baroreflex sensitivity via a pathway involving the parabrachial nucleus.

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

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    Spina, D; Page, C P

    2013-10-01

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

  14. Inferior alveolar nerve injury with laryngeal mask airway: a case report.

    LENUS (Irish Health Repository)

    Hanumanthaiah, Deepak

    2011-01-01

    The incidence of damage to the individual cranial nerves and their branches associated with laryngeal mask airway use is low; there have been case reports of damage to the lingual nerve, hypoglossal nerve and recurrent laryngeal nerve. To the best of our knowledge we present the first reported case of inferior alveolar nerve injury associated with laryngeal mask airway use.

  15. Modulation of afferent nerve activity by prostaglandin E2 upon urinary bladder distension in rats.

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    Kuga, Nahoko; Tanioka, Asao; Hagihara, Koichiro; Kawai, Tomoyuki

    2016-05-01

    What is the central question of this study? It has been widely assumed that C fibres innervating the bladder are mainly excited in overactive bladder syndrome. However, it remains unclear whether Aδ fibres are also activated in pathological conditions. What is the main finding and its importance? We found that a certain population of Aδ fibres, which become active specifically at a bladder pressure of more than 15 cmH2 O in normal conditions, showed increased excitability in conditions of prostaglandin E2 -induced overactive bladder. This result suggests that a certain population of Aδ fibres, together with C fibres, triggers pathophysiological activity. In overactive bladder syndrome, afferent C fibres innervating the bladder show an increased activity level. However, it remains unclear whether all C fibres are highly activated and whether Aδ fibres, the other type of bladder afferent fibre, are also involved in pathological conditions. To address these questions, we analysed the relationship between bladder pressure and single-unit firing patterns of afferent nerves in the left L6 dorsal roots in living rats. The recorded fibres were classified as Aδ fibres or C fibres based on the response to 0.3 μm tetrodotoxin. Certain populations of both Aδ fibres and C fibres were activated at bladder pressures below 15 cmH2 O (classified as low-threshold fibres), indicating their potential contribution to detection of normal bladder filling. Intravesical administration of prostaglandin E2 (PGE2 ) induced hyperexcitation in approximately half of such C fibres, whereas the activity patterns of low-threshold Aδ fibres were unchanged. All fibres, regardless of type, which were almost silent in control conditions (classified as high-threshold fibres), were activated by application of PGE2 . Notably, the firing patterns of Aδ fibres, rather than C fibres, were highly time locked to PGE2 -induced micro-oscillation of bladder pressure. These modulatory effects

  16. Interpretation of muscle spindle afferent nerve response to passive muscle stretch recorded with thin-film longitudinal intrafascicular electrodes.

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    Djilas, Milan; Azevedo-Coste, Christine; Guiraud, David; Yoshida, Ken

    2009-10-01

    In this study, we explored the feasibility of estimating muscle length in passive conditions by interpreting nerve responses from muscle spindle afferents recorded with thin-film longitudinal intrafascicular electrodes. Afferent muscle spindle response to passive stretch was recorded in ten acute rabbit experiments. A newly proposed first-order model of muscle spindle response to passive sinusoidal muscle stretch manages to capture the relationship between afferent neural firing rate and muscle length. We demonstrate that the model can be used to track random motion trajectories with bandwidth from 0.1 to 1 Hz over a range of 4 mm with a muscle length estimation error of 0.3 mm (1.4 degrees of joint angle). When estimation is performed using four-channel ENG there is a 50% reduction in estimate variation, compared to using single-channel recordings.

  17. Movement and afferent representations in human motor areas: a simultaneous neuroimaging and transcranial magnetic/peripheral nerve-stimulation study

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    Hitoshi eShitara

    2013-09-01

    Full Text Available Neuroimaging combined with transcranial magnetic stimulation (TMS to primary motor cortex (M1 is an emerging technique that can examine motor-system functionality through evoked activity. However, because sensory afferents from twitching muscles are widely represented in motor areas the amount of evoked activity directly resulting from TMS remains unclear. We delivered suprathreshold TMS to left M1 or electrically stimulated the right median nerve (MNS in 18 healthy volunteers while simultaneously conducting functional magnetic resonance imaging and monitoring with electromyography (EMG. We examined in detail the localization of TMS-, muscle afferent- and superficial afferent-induced activity in M1 subdivisions. Muscle afferent- and TMS-evoked activity occurred mainly in rostral M1, while superficial afferents generated a slightly different activation distribution. In 12 participants who yielded quantifiable EMG, differences in brain activity ascribed to differences in movement-size were adjusted using integrated information from the EMGs. Sensory components only explained 10-20% of the suprathreshold TMS-induced activity, indicating that locally and remotely evoked activity in motor areas mostly resulted from the recruitment of neural and synaptic activity. The present study appears to justify the use of fMRI combined with suprathreshold TMS to M1 for evoked motor network imaging.

  18. Characterization of muscle spindle afferents in the adult mouse using an in vitro muscle-nerve preparation.

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    Katherine A Wilkinson

    Full Text Available We utilized an in vitro adult mouse extensor digitorum longus (EDL nerve-attached preparation to characterize the responses of muscle spindle afferents to ramp-and-hold stretch and sinusoidal vibratory stimuli. Responses were measured at both room (24°C and muscle body temperature (34°C. Muscle spindle afferent static firing frequencies increased linearly in response to increasing stretch lengths to accurately encode the magnitude of muscle stretch (tested at 2.5%, 5% and 7.5% of resting length [Lo]. Peak firing frequency increased with ramp speeds (20% Lo/sec, 40% Lo/sec, and 60% Lo/sec. As a population, muscle spindle afferents could entrain 1:1 to sinusoidal vibrations throughout the frequency (10-100 Hz and amplitude ranges tested (5-100 µm. Most units preferentially entrained to vibration frequencies close to their baseline steady-state firing frequencies. Cooling the muscle to 24°C decreased baseline firing frequency and units correspondingly entrained to slower frequency vibrations. The ramp component of stretch generated dynamic firing responses. These responses and related measures of dynamic sensitivity were not able to categorize units as primary (group Ia or secondary (group II even when tested with more extreme length changes (10% Lo. We conclude that the population of spindle afferents combines to encode stretch in a smoothly graded manner over the physiological range of lengths and speeds tested. Overall, spindle afferent response properties were comparable to those seen in other species, supporting subsequent use of the mouse genetic model system for studies on spindle function and dysfunction in an isolated muscle-nerve preparation.

  19. Intercellular K⁺ accumulation depolarizes Type I vestibular hair cells and their associated afferent nerve calyx.

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    Contini, D; Zampini, V; Tavazzani, E; Magistretti, J; Russo, G; Prigioni, I; Masetto, S

    2012-12-27

    Mammalian vestibular organs contain two types of sensory receptors, named Type I and Type II hair cells. While Type II hair cells are contacted by several small afferent nerve terminals, the basolateral surface of Type I hair cells is almost entirely enveloped by a single large afferent nerve terminal, called calyx. Moreover Type I, but not Type II hair cells, express a low-voltage-activated outward K(+) current, I(K,L), which is responsible for their much lower input resistance (Rm) at rest as compared to Type II hair cells. The functional meaning of I(K,L) and associated calyx is still enigmatic. By combining the patch-clamp whole-cell technique with the mouse whole crista preparation, we have recorded the current- and voltage responses of in situ hair cells. Outward K(+) current activation resulted in K(+) accumulation around Type I hair cells, since it induced a rightward shift of the K(+) reversal potential the magnitude of which depended on the amplitude and duration of K(+) current flow. Since this phenomenon was never observed for Type II hair cells, we ascribed it to the presence of a residual calyx limiting K(+) efflux from the synaptic cleft. Intercellular K(+) accumulation added a slow (τ>100ms) depolarizing component to the cell voltage response. In a few cases we were able to record from the calyx and found evidence for intercellular K(+) accumulation as well. The resulting depolarization could trigger a discharge of action potentials in the afferent nerve fiber. Present results support a model where pre- and postsynaptic depolarization produced by intercellular K(+) accumulation cooperates with neurotransmitter exocytosis in sustaining afferent transmission arising from Type I hair cells. While vesicular transmission together with the low Rm of Type I hair cells appears best suited for signaling fast head movements, depolarization produced by intercellular K(+) accumulation could enhance signal transmission during slow head movements. Copyright

  20. Evoked pain analgesia in chronic pelvic pain patients using respiratory-gated auricular vagal afferent nerve stimulation.

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    Napadow, Vitaly; Edwards, Robert R; Cahalan, Christine M; Mensing, George; Greenbaum, Seth; Valovska, Assia; Li, Ang; Kim, Jieun; Maeda, Yumi; Park, Kyungmo; Wasan, Ajay D

    2012-06-01

    Previous vagus nerve stimulation (VNS) studies have demonstrated antinociceptive effects, and recent noninvasive approaches, termed transcutaneous-vagus nerve stimulation (t-VNS), have utilized stimulation of the auricular branch of the vagus nerve in the ear. The dorsal medullary vagal system operates in tune with respiration, and we propose that supplying vagal afferent stimulation gated to the exhalation phase of respiration can optimize t-VNS. Counterbalanced, crossover study. Patients with chronic pelvic pain (CPP) due to endometriosis in a specialty pain clinic. INTERVENTIONS/OUTCOMES: We evaluated evoked pain analgesia for respiratory-gated auricular vagal afferent nerve stimulation (RAVANS) compared with nonvagal auricular stimulation (NVAS). RAVANS and NVAS were evaluated in separate sessions spaced at least 1 week apart. Outcome measures included deep-tissue pain intensity, temporal summation of pain, and anxiety ratings, which were assessed at baseline, during active stimulation, immediately following stimulation, and 15 minutes after stimulus cessation. RAVANS demonstrated a trend for reduced evoked pain intensity and temporal summation of mechanical pain, and significantly reduced anxiety in N = 15 CPP patients, compared with NVAS, with moderate to large effect sizes (η(2) > 0.2). Chronic pain disorders such as CPP are in great need of effective, nonpharmacological options for treatment. RAVANS produced promising antinociceptive effects for quantitative sensory testing (QST) outcomes reflective of the noted hyperalgesia and central sensitization in this patient population. Future studies should evaluate longer-term application of RAVANS to examine its effects on both QST outcomes and clinical pain. Wiley Periodicals, Inc.

  1. Sarcoidosis with Major Airway, Vascular and Nerve Compromise

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    Hiroshi Sekiguchi

    2013-01-01

    Full Text Available The present report describes a 60-year-old Caucasian woman who presented with progressive dyspnea, cough and wheeze. A computed tomography scan of the chest showed innumerable bilateral inflammatory pulmonary nodules with bronchovascular distribution and a mediastinal and hilar infiltrative process with calcified lymphadenopathy leading to narrowing of lobar bronchi and pulmonary arteries. An echocardiogram revealed pulmonary hypertension. Bronchoscopy showed left vocal cord paralysis and significant narrowing of the bilateral bronchi with mucosal thickening and multiple nodules. Transbronchial biopsy was compatible with sarcoidosis. Despite balloon angioplasty of the left lower lobe and pulmonary artery, and medical therapy with oral corticosteroids, her symptoms did not significantly improve. To the authors’ knowledge, the present report describes the first case of pulmonary sarcoidosis resulting in major airway, vascular and nerve compromise due to compressive lymphadenopathy and suspected concurrent granulomatous infiltration. Its presentation mimicked idiopathic mediastinal fibrosis.

  2. Chronic kidney disease impairs renal nerve and haemodynamic reflex responses to vagal afferent input through a central mechanism.

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    Salman, Ibrahim M; Hildreth, Cara M; Phillips, Jacqueline K

    2017-05-01

    We investigated age- and sex-related changes in reflex renal sympathetic nerve activity (RSNA) and haemodynamic responses to vagal afferent stimulation in a rodent model of chronic kidney disease (CKD). Using anaesthetised juvenile (7-8weeks) and adult (12-13weeks) Lewis Polycystic Kidney (LPK) and Lewis control rats of either sex (n=63 total), reflex changes in RSNA, heart rate (HR) and mean arterial pressure (MAP) to vagal afferent stimulation (5-s train, 4.0V, 2.0-ms pulses, 1-16Hz) were measured. In all groups, stimulation of the vagal afferents below 16Hz produced frequency-dependent reductions in RSNA, HR and MAP, while a 16Hz stimulus produced an initial sympathoinhibition followed by sympathoexcitation. In juvenile LPK versus age-matched Lewis, sympathoinhibition was reduced when responses were expressed as % baseline (P<0.05), but not as microvolts, while bradycardic responses were greater. Reflex depressor responses were greater (P=0.015) only in juvenile female LPK. In adult LPK, reflex sympathoinhibition (%) was blunted (P<0.05), and an age-related decline apparent (when expressed as microvolts). Reflex reductions in HR and MAP were only diminished (P<0.05) in adult female LPK versus age-matched Lewis. Peak reflex sympathoexcitation at 16Hz did not differ between groups; however, area under the curve values were greater in the LPK versus Lewis (overall, 9±1 versus 19±3μVs, P<0.05) irrespective of age, suggestive of enhanced sympathoexcitatory drive in the LPK. Our data demonstrates a progressive deficit in the central processing of vagal afferent input and a differential sex influence on reflex regulation of autonomic function and blood pressure homeostasis in CKD. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  3. Spike Sorting of Muscle Spindle Afferent Nerve Activity Recorded with Thin-Film Intrafascicular Electrodes

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    Milan Djilas

    2010-01-01

    Full Text Available Afferent muscle spindle activity in response to passive muscle stretch was recorded in vivo using thin-film longitudinal intrafascicular electrodes. A neural spike detection and classification scheme was developed for the purpose of separating activity of primary and secondary muscle spindle afferents. The algorithm is based on the multiscale continuous wavelet transform using complex wavelets. The detection scheme outperforms the commonly used threshold detection, especially with recordings having low signal-to-noise ratio. Results of classification of units indicate that the developed classifier is able to isolate activity having linear relationship with muscle length, which is a step towards online model-based estimation of muscle length that can be used in a closed-loop functional electrical stimulation system with natural sensory feedback.

  4. Spike sorting of muscle spindle afferent nerve activity recorded with thin-film intrafascicular electrodes.

    Science.gov (United States)

    Djilas, Milan; Azevedo-Coste, Christine; Guiraud, David; Yoshida, Ken

    2010-01-01

    Afferent muscle spindle activity in response to passive muscle stretch was recorded in vivo using thin-film longitudinal intrafascicular electrodes. A neural spike detection and classification scheme was developed for the purpose of separating activity of primary and secondary muscle spindle afferents. The algorithm is based on the multiscale continuous wavelet transform using complex wavelets. The detection scheme outperforms the commonly used threshold detection, especially with recordings having low signal-to-noise ratio. Results of classification of units indicate that the developed classifier is able to isolate activity having linear relationship with muscle length, which is a step towards online model-based estimation of muscle length that can be used in a closed-loop functional electrical stimulation system with natural sensory feedback.

  5. Relief of upper airway obstruction with hypoglossal nerve stimulation in the canine.

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    Goding, G S; Eisele, D W; Testerman, R; Smith, P L; Roertgen, K; Schwartz, A R

    1998-02-01

    Hypoglossal nerve stimulation was investigated as a method to relieve an induced upper airway obstruction. Six dogs were implanted with a cuff electrode applied to each hypoglossal nerve and a pulse generator. After 4 weeks, the hypoglossal nerve was stimulated (50% duty cycle) for up to 8 weeks. At 12 weeks a double tracheotomy was placed, with a negative pressure intermittently applied to the upper limb, simulating inspiratory airway pressure. Unilateral hypoglossal nerve stimulation improved peak upper airway flow from an average of 0.1 L/s to 1.6 L/s (P = 0.0001). Seventy-seven percent of the maximum possible flow (explanted tracheotomy tube) was obtained with unilateral stimulation. Histopathological evaluation revealed no nerve damage secondary to chronic stimulation. This study provides support for clinical trials of hypoglossal stimulation for obstructive sleep apnea.

  6. Biochemical evidence that L-glutamate is a neurotransmitter of primary vagal afferent nerve fibers

    International Nuclear Information System (INIS)

    Perrone, M.H.

    1981-01-01

    To determine in rat if vagal afferent fibers projecting into the intermediate one third of the nucleus tractus solitarius (NTS), the site of termination of baroafferents, utilize glutamate as a neurotransmitter, the high-affinity uptake of [ 3 H]L-glutamate and content of glutamate were analyzed in micropunches of rat brain stem. The intermediate NTS contains a high-affinity synaptosomal uptake system for [ 3 H]L-glutamate that is greater in capacity than that in areas adjacent to the NTS; it is almost two-fold higher than uptake in medial septum and nucleus accumbens and equal to that of hippocampal regions purportedly containing a rich glutamatergic innervation. Unilateral ablation of the nodose ganglion (i.e. cells of origin of vagal afferents) resulted, within 24 h in a prolonged significant reduction, to 56% of control, of [ 3 H]L-glutamate uptake, bilaterally in the NTS. The reduction of Na + -dependent synaptosomal uptake of [ 3 H]L-glutamate, resulted from a decrease in Vsub(max) without change in the Ksub(m) of the process, was anatomically restricted to the intermediate NTS, and was not associated with changes in [ 3 H]GABA uptake. The content of glutamate in the NTS was significantly (P < 0.01) decreased by 30% 7 days following unilateral extirpation of the nodose ganglion without changes in the concentrations of aspartate, glycine, glutamine, or GABA. A population of vagal afferent fibers projecting to NTS are glutamatergic. The results are consistent with the hypothesis obtained by physiological and pharmacological techniques that glutamate is a neurotransmitter of baroafferents. (Auth.)

  7. Coordinated Respiratory Motor Activity in Nerves Innervating the Upper Airway Muscles in Rats.

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    Satoshi Tachikawa

    Full Text Available Maintaining the patency of the upper airway during breathing is of vital importance. The activity of various muscles is related to the patency of the upper airway. In the present study, we examined the respiratory motor activity in the efferent nerves innervating the upper airway muscles to determine the movements of the upper airway during respiration under normocapnic conditions (pH = 7.4 and in hypercapnic acidosis (pH = 7.2. Experiments were performed on arterially perfused decerebrate rats aged between postnatal days 21-35. We recorded the efferent nerve activity in a branch of the cervical spinal nerve innervating the infrahyoid muscles (CN, the hypoglossal nerve (HGN, the external branch of the superior laryngeal nerve (SLN, and the recurrent laryngeal nerve (RLN with the phrenic nerve (PN. Inspiratory nerve discharges were observed in all these nerves under normocapnic conditions. The onset of inspiratory discharges in the CN and HGN was slightly prior to those in the SLN and RLN. When the CO2 concentration in the perfusate was increased from 5% to 8% to prepare for hypercapnic acidosis, the peak amplitudes of the inspiratory discharges in all the recorded nerves were increased. Moreover, hypercapnic acidosis induced pre-inspiratory discharges in the CN, HGN, SLN, and RLN. The onset of pre-inspiratory discharges in the CN, HGN, and SLN was prior to that of discharges in the RLN. These results suggest that the securing of the airway that occurs a certain time before dilation of the glottis may facilitate ventilation and improve hypercapnic acidosis.

  8. Lack of evidence for sprouting of Aβ afferents into the superficial laminas of the spinal cord dorsal horn after nerve section

    OpenAIRE

    Hughes, D.I.; Scott, D.T.; Todd, A.J.; Riddell, J.S.

    2003-01-01

    The central arborizations of large myelinated cutaneous afferents normally extend as far dorsally as the ventral part of lamina II in rat spinal cord. Woolf et al. (1992) reported that after nerve injury some of these afferents sprouted into lamina I and the dorsal part of lamina II, and it has been suggested that this could contribute to allodynia associated with neuropathic pain. Part of the evidence for sprouting was on the basis of the use of cholera toxin B subunit as a selective tracer ...

  9. High sensitivity recording of afferent nerve activity using ultra-compliant microchannel electrodes: an acute in vivo validation

    Science.gov (United States)

    Minev, Ivan R.; Chew, Daniel J.; Delivopoulos, Evangelos; Fawcett, James W.; Lacour, Stéphanie P.

    2012-04-01

    Neuroprostheses interfaced with transected peripheral nerves are technological routes to control robotic limbs as well as convey sensory feedback to patients suffering from traumatic neural injuries or degenerative diseases. To maximize the wealth of data obtained in recordings, interfacing devices are required to have intrafascicular resolution and provide high signal-to-noise ratio (SNR) recordings. In this paper, we focus on a possible building block of a three-dimensional regenerative implant: a polydimethylsiloxane (PDMS) microchannel electrode capable of highly sensitive recordings in vivo. The PDMS 'micro-cuff' consists of a 3.5 mm long (100 µm × 70 µm cross section) microfluidic channel equipped with five evaporated Ti/Au/Ti electrodes of sub-100 nm thickness. Individual electrodes have average impedance of 640 ± 30 kΩ with a phase angle of -58 ± 1 degrees at 1 kHz and survive demanding mechanical handling such as twisting and bending. In proof-of-principle acute implantation experiments in rats, surgically teased afferent nerve strands from the L5 dorsal root were threaded through the microchannel. Tactile stimulation of the skin was reliably monitored with the three inner electrodes in the device, simultaneously recording signal amplitudes of up to 50 µV under saline immersion. The overall SNR was approximately 4. A small but consistent time lag between the signals arriving at the three electrodes was observed and yields a fibre conduction velocity of 30 m s-1. The fidelity of the recordings was verified by placing the same nerve strand in oil and recording activity with hook electrodes. Our results show that PDMS microchannel electrodes open a promising technological path to 3D regenerative interfaces.

  10. Correction: Inferior alveolar nerve injury with laryngeal mask airway: a case report.

    LENUS (Irish Health Repository)

    Hanumanthaiah, Deepak

    2011-11-30

    ABSTRACT: Following the publication of our article [Inferior alveolar nerve injury with laryngeal mask airway: a case report. Journal of Medical Case Reports 2011, 5:122] it was brought to our attention that we inadvertently used the registered trademark of the Laryngeal Mask Company Limited (LMA) as the abbreviation for laryngeal mask airway. A Portex(R) Soft Seal(R) Laryngeal Mask was used and not a device manufactured by the Laryngeal Mask Company.

  11. Bladder activation: afferent mechanisms.

    Science.gov (United States)

    Andersson, Karl-Erik

    2002-05-01

    The major function of the lower urinary tract is to store and periodically evacuate urine from the bladder. This requires coordination of the smooth muscles of the bladder and urethra, and of the striated muscles of the outflow region and pelvic floor by a complex neural control system. Lumbosacral afferent fibers (pelvic afferents), but also afferents in the hypogastric and pudendal nerves, are of major importance for the regulation of the mechanisms for continence and micturition. In the bladder, afferent nerves have been identified suburothelially as well as in the detrusor muscle. Suburothelially, they form a plexus that lies immediately beneath the epithelial lining. This plexus is particularly dense in the bladder neck and the trigone. The most important afferents for the micturition process are myelinated Adelta-fibers and unmyelinated C-fibers. Immunocytochemical and tracing studies have revealed that numerous peptides, including substance P, calcitonin gene-related peptide, vasoactive intestinal polypeptide, enkephalins, and cholecystokinin are localized either alone, or in combination, in afferent pathways of the bladder and urethra. The receptors on these nerves include: vanilloid receptors, purinoceptors, tachykinin, and prostanoid receptors. Extracellular adenosine triphosphate (ATP) has been found to mediate excitation of small-diameter sensory neurons via P2X3 receptors, and it has been proposed that in the bladder, distention causes release of ATP from the urothelium. ATP, in turn, can activate P2X3 receptors on suburothelial afferent nerve terminals to evoke a neural discharge. However, it is most likely that a cascade of inhibitory and stimulatory transmitters/mediators, as well as ATP, are involved in the transduction mechanisms underlying the activation of afferent fibers during bladder filling.

  12. Chronic implantation of cuff electrodes on the pelvic nerve in rats is well tolerated and does not compromise afferent or efferent fibre functionality

    Science.gov (United States)

    Crook, J. J.; Brouillard, C. B. J.; Irazoqui, P. P.; Lovick, T. A.

    2018-04-01

    Objective. Neuromodulation of autonomic nerve activity to regulate physiological processes is an emerging field. Vagal stimulation has received most attention whereas the potential of modulate visceral function by targeting autonomic nerves within the abdominal cavity remains under-exploited. Surgery to locate intra-abdominal targets is inherently more stressful than for peripheral nerves. Electrode leads risk becoming entrapped by intestines and loss of functionality in the nerve-target organ connection could result from electrode migration or twisting. Since nociceptor afferents are intermingled with similar-sized visceral autonomic fibres, stimulation may induce pain. In anaesthetised rats high frequency stimulation of the pelvic nerve can suppress urinary voiding but it is not known how conscious animals would react to this procedure. Our objective therefore was to determine how rats tolerated chronic implantation of cuff electrodes on the pelvic nerve, whether nerve stimulation would be aversive and whether nerve-bladder functionality would be compromised. Approach. We carried out a preliminary de-risking study to investigate how conscious rats tolerated chronic implantation of electrodes on the pelvic nerve, their responsiveness to intermittent high frequency stimulation and whether functionality of the nerve-bladder connection became compromised. Main results. Implantation of cuff electrodes was well-tolerated. The normal diurnal pattern of urinary voiding was not disrupted. Pelvic nerve stimulation (up to 4 mA, 3 kHz) for 30 min periods evoked mild alerting at stimulus onset but no signs of pain. Stimulation evoked a modest (<0.5 °C) increase in nerve temperature but the functional integrity of the nerve-bladder connection, reflected by contraction of the detrusor muscle in response to 10 Hz nerve stimulation, was not compromised. Significance. Chronic implantation of cuff electrodes on the pelvic nerve was found to be a well-tolerated procedure in

  13. Closed-loop stimulation of hypoglossal nerve in a dog model of upper airway obstruction.

    Science.gov (United States)

    Sahin, M; Durand, D M; Haxhiu, M A

    2000-07-01

    Electrical stimulation of upper airway (UAW) muscles has been under investigation as a treatment method for obstructive sleep apnea (OSA). Particular attention has been given to the electrical activation of the genioglossal muscle, either directly or via the stimulation of the hypoglossal nerve (HG), since the genioglossus is the main tongue protrusor muscle. Regardless of the stimulation site or method, an implantable electrical stimulation device for OSA patients will require a reliable method for detection of obstructive breaths to apply the stimulation when needed. In this paper, we test the hypothesis that the activity of the HG nerve can be used as a feedback signal for closed-loop stimulation of the HG nerve in an animal model of UAW obstruction where a force is applied on the submental region to physically narrow the airways. As an advantage, the method uses a single electrode for both recording and stimulation of the HG nerve. Simple linear filtering techniques were found to be adequate for producing the trigger signal for the electrical stimulation from the HG recordings. Esophageal pressure, which was used to estimate the size of the UAW passage, returned to the preloading values during closed-loop stimulation of the HG nerve. The data demonstrate the feasibility of the closed-loop stimulation of the HG nerve using its activity as the feedback signal.

  14. Impediment in upper airway stabilizing forces assessed by phrenic nerve stimulation in sleep apnea patients

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    Vérin E

    2005-09-01

    Full Text Available Abstract Background The forces developed during inspiration play a key role in determining upper airway stability and the occurrence of nocturnal breathing disorders. Phrenic nerve stimulation applied during wakefulness is a unique tool to assess Upper airway dynamic properties and to measure the overall mechanical effects of the inspiratory process on UA stability. Objectives To compare the flow/pressure responses to inspiratory and expiratory twitches between sleep apnea subjects and normal subjects. Methods Inspiratory and expiratory twitches using magnetic nerve stimulation completed in eleven untreated sleep apnea subjects and ten normal subjects. Results In both groups, higher flow and pressure were reached during inspiratory twitches. The two groups showed no differences in expiratory twitch parameters. During inspiration, the pressure at which flow-limitation occurred was more negative in normals than in apneic subjects, but not reaching significance (p = 0.07. The relationship between pharyngeal pressure and flow adequately fitted with a polynomial regression model providing a measurement of upper airway critical pressure during twitch. This pressure significantly decreased in normals from expiratory to inspiratory twitches (-11.1 ± 1.6 and -15.7 ± 1.0 cm H2O respectively, 95% CI 1.6–7.6, p Conclusion Inspiratory-related upper airway dilating forces are impeded in sleep apnea patients.

  15. The nerve growth factor and its receptors in airway inflammatory diseases.

    Science.gov (United States)

    Freund-Michel, V; Frossard, N

    2008-01-01

    The nerve growth factor (NGF) belongs to the neurotrophin family and induces its effects through activation of 2 distinct receptor types: the tropomyosin-related kinase A (TrkA) receptor, carrying an intrinsic tyrosine kinase activity in its intracellular domain, and the receptor p75 for neurotrophins (p75NTR), belonging to the death receptor family. Through activation of its TrkA receptor, NGF activates signalling pathways, including phospholipase Cgamma (PLCgamma), phosphatidyl-inositol 3-kinase (PI3K), the small G protein Ras, and mitogen-activated protein kinases (MAPK). Through its p75NTR receptor, NGF activates proapoptotic signalling pathways including the MAPK c-Jun N-terminal kinase (JNK), ceramides, and the small G protein Rac, but also activates pathways promoting cell survival through the transcription factor nuclear factor-kappaB (NF-kappaB). NGF was first described by Rita Levi-Montalcini and collaborators as an important factor involved in nerve differentiation and survival. Another role for NGF has since been established in inflammation, in particular of the airways, with increased NGF levels in chronic inflammatory diseases. In this review, we will first describe NGF structure and synthesis and NGF receptors and their signalling pathways. We will then provide information about NGF in the airways, describing its expression and regulation, as well as pointing out its potential role in inflammation, hyperresponsiveness, and remodelling process observed in airway inflammatory diseases, in particular in asthma.

  16. Unilateral Hypoglossal Nerve Palsy after Use of the Laryngeal Mask Airway Supreme

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    Kenichi Takahoko

    2014-01-01

    Full Text Available Purpose. Hypoglossal nerve palsy after use of the laryngeal mask airway (LMA is an exceptionally rare complication. We present the first case of unilateral hypoglossal nerve palsy after use of the LMA Supreme. Clinical Features. A healthy 67-year-old female was scheduled for a hallux valgus correction under general anesthesia combined with femoral and sciatic nerve blocks. A size 4 LMA Supreme was inserted successfully at the first attempt and the cuff was inflated with air at an intracuff pressure of 60 cmH2O using cuff pressure gauge. Anesthesia was maintained with oxygen, nitrous oxide (67%, and sevoflurane under spontaneous breathing. The surgery was uneventful and the duration of anesthesia was two hours. The LMA was removed as the patient woke and there were no immediate postoperative complications. The next morning, the patient complained of dysarthria and dysphasia. These symptoms were considered to be caused by the LMA compressing the nerve against the hyoid bone. Conservative treatment was chosen and the paralysis recovered completely after 5 months. Conclusion. Hypoglossal nerve injury may occur despite correct positioning of the LMA under the appropriate intracuff pressure. A follow-up period of at least 6 months should be taken into account for the recovery.

  17. Chronic recordings of hypoglossal nerve activity in a dog model of upper airway obstruction.

    Science.gov (United States)

    Sahin, M; Durand, D M; Haxhiu, M A

    1999-12-01

    The activity of the hypoglossal nerve was recorded during pharyngeal loading in sleeping dogs with chronically implanted cuff electrodes. Three self-coiling spiral-cuff electrodes were implanted in two beagles for durations of 17, 7, and 6 mo. During quiet wakefulness and sleep, phasic hypoglossal activity was either very small or not observable above the baseline noise. Applying a perpendicular force on the submental region by using a mechanical device to narrow the pharyngeal airway passage increased the phasic hypoglossal activity, the phasic esophageal pressure, and the inspiratory time in the next breath during non-rapid-eye-movement sleep. The phasic hypoglossal activity sustained at the elevated level while the force was present and increased with increasing amounts of loading. The hypoglossal nerve was very active in rapid-eye-movement sleep, especially when the submental force was present. The data demonstrate the feasibility of chronic recordings of the hypoglossal nerve with cuff electrodes and show that hypoglossal activity has a fast and sustained response to the internal loading of the pharynx induced by applying a submental force during non-rapid-eye-movement sleep.

  18. Arginase attenuates inhibitory nonadrenergic noncholinergic nerve-induced nitric oxide generation and airway smooth muscle relaxation

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    Meurs Herman

    2005-03-01

    Full Text Available Abstract Background Recent evidence suggests that endogenous arginase activity potentiates airway responsiveness to methacholine by attenuation of agonist-induced nitric oxide (NO production, presumably by competition with epithelial constitutive NO synthase for the common substrate, L-arginine. Using guinea pig tracheal open-ring preparations, we now investigated the involvement of arginase in the modulation of neuronal nitric oxide synthase (nNOS-mediated relaxation induced by inhibitory nonadrenergic noncholinergic (iNANC nerve stimulation. Methods Electrical field stimulation (EFS; 150 mA, 4 ms, 4 s, 0.5 – 16 Hz-induced relaxation was measured in tracheal preparations precontracted to 30% with histamine, in the presence of 1 μM atropine and 3 μM indomethacin. The contribution of NO to the EFS-induced relaxation was assessed by the nonselective NOS inhibitor L-NNA (0.1 mM, while the involvement of arginase activity in the regulation of EFS-induced NO production and relaxation was investigated by the effect of the specific arginase inhibitor nor-NOHA (10 μM. Furthermore, the role of substrate availability to nNOS in EFS-induced relaxation was measured in the presence of various concentrations of exogenous L-arginine. Results EFS induced a frequency-dependent relaxation, ranging from 6.6 ± 0.8% at 0.5 Hz to 74.6 ± 1.2% at 16 Hz, which was inhibited with the NOS inhibitor L-NNA by 78.0 ± 10.5% at 0.5 Hz to 26.7 ± 7.7% at 8 Hz (P Conclusion The results indicate that endogenous arginase activity attenuates iNANC nerve-mediated airway relaxation by inhibition of NO generation, presumably by limiting L-arginine availability to nNOS.

  19. Airway irritation and cough evoked by acid: from human to ion channel

    Science.gov (United States)

    Gu, Qihai; Lee, Lu-Yuan

    2011-01-01

    Inhalation or aspiration of acid solution evokes airway defense responses such as cough and reflex bronchoconstriction, resulting from activation of vagal bronchopulmonary C-fibers and Aδ afferents. The stimulatory effect of hydrogen ion on these sensory nerves is generated by activation of two major types of ion channels expressed in these neurons: a rapidly activating and inactivating current mediated through ASICs, and a slow sustaining current via activation of TRPV1. Recent studies have shown that these acid-evoked responses are elevated during airway inflammatory reaction, revealing the potential convergence of a wide array of inflammatory signaling on these ion channels. Since pH in the airway fluid drops substantially in patients with inflammatory airway diseases, these heightened stimulatory effects of acid on airway sensory nerves may play a part in the manifestation of airway irritation and excessive cough under those pathophysiological conditions. PMID:21543258

  20. Macrophage presence is essential for the regeneration of ascending afferent fibres following a conditioning sciatic nerve lesion in adult rats

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    Smith Malcolm

    2011-01-01

    Full Text Available Abstract Background Injury to the peripheral branch of dorsal root ganglia (DRG neurons prior to injury to the central nervous system (CNS DRG branch results in the regeneration of the central branch. The exact mechanism mediating this regenerative trigger is not fully understood. It has been proposed that following peripheral injury, the intraganglionic inflammatory response by macrophage cells plays an important role in the pre-conditioning of injured CNS neurons to regenerate. In this study, we investigated whether the presence of macrophage cells is crucial for this type of regeneration to occur. We used a clodronate liposome technique to selectively and temporarily deplete these cells during the conditioning phase of DRG neurons. Results Retrograde and anterograde tracing results indicated that in macrophage-depleted animals, the regenerative trigger characteristic of pre-conditioned DRG neurons was abolished as compared to injury matched-control animals. In addition, depletion of macrophage cells led to: (i a reduction in macrophage infiltration into the CNS compartment even after cellular repopulation, (ii astrocyte up-regulation at rostral regions and down-regulation in brain derived neurotrophic factor (BDNF concentration in the serum. Conclusion Activation of macrophage cells in response to the peripheral nerve injury is essential for the enhanced regeneration of ascending sensory neurons.

  1. Failure of action potential propagation in sensory neurons: mechanisms and loss of afferent filtering in C-type units after painful nerve injury.

    Science.gov (United States)

    Gemes, Geza; Koopmeiners, Andrew; Rigaud, Marcel; Lirk, Philipp; Sapunar, Damir; Bangaru, Madhavi Latha; Vilceanu, Daniel; Garrison, Sheldon R; Ljubkovic, Marko; Mueller, Samantha J; Stucky, Cheryl L; Hogan, Quinn H

    2013-02-15

    The T-junction of sensory neurons in the dorsal root ganglion (DRG) is a potential impediment to action potential (AP) propagation towards the CNS. Using intracellular recordings from rat DRG neuronal somata during stimulation of the dorsal root, we determined that the maximal rate at which all of 20 APs in a train could successfully transit the T-junction (following frequency) was lowest in C-type units, followed by A-type units with inflected descending limbs of the AP, and highest in A-type units without inflections. In C-type units, following frequency was slower than the rate at which AP trains could be produced in either dorsal root axonal segments or in the soma alone, indicating that the T-junction is a site that acts as a low-pass filter for AP propagation. Following frequency was slower for a train of 20 APs than for two, indicating that a cumulative process leads to propagation failure. Propagation failure was accompanied by diminished somatic membrane input resistance, and was enhanced when Ca(2+)-sensitive K(+) currents were augmented or when Ca(2+)-sensitive Cl(-) currents were blocked. After peripheral nerve injury, following frequencies were increased in axotomized C-type neurons and decreased in axotomized non-inflected A-type neurons. These findings reveal that the T-junction in sensory neurons is a regulator of afferent impulse traffic. Diminished filtering of AP trains at the T-junction of C-type neurons with axotomized peripheral processes could enhance the transmission of activity that is ectopically triggered in a neuroma or the neuronal soma, possibly contributing to pain generation.

  2. Long-term nicotine exposure dampens LPS-induced nerve-mediated airway hyperreactivity in murine airways.

    Science.gov (United States)

    Xu, Yuan; Cardell, Lars-Olaf

    2017-09-01

    Nicotine is a major component of cigarette smoke. It causes addiction and is used clinically to aid smoke cessation. The aim of the present study is to investigate the effect of nicotine on lipopolysaccharide (LPS)-induced airway hyperreactivity (AHR) and to explore the potential involvement of neuronal mechanisms behind nicotine's effects in murine models in vivo and in vitro. BALB/c mice were exposed to nicotine in vivo via subcutaneous Alzet osmotic minipumps containing nicotine tartate salt solution (24 mg·kg -1 ·day -1 ) for 28 days. LPS (0.1 mg/ml, 20 µl) was administered intranasally for 3 consecutive days during the end of this period. Lung functions were measured with flexiVent. For the in vitro experiments, mice tracheae were organcultured with either nicotine (10 μM) or vehicle (DMSO, 0.1%) for 4 days. Contractile responses of the tracheal segments were measured in myographs following electric field stimulation (EFS; increasing frequencies of 0.2 to 12.8 Hz) before and after incubation with 10 µg/ml LPS for 1 h. Results showed that LPS induced AHR to methacholine in vivo and increased contractile responses to EFS in vitro. Interestingly, long-term nicotine exposure markedly dampened this LPS-induced AHR both in vitro and in vivo. Tetrodotoxin (TTX) inhibited LPS-induced AHR but did not further inhibit nicotine-suppressed AHR in vivo. In conclusion, long-term nicotine exposure dampened LPS-induced AHR. The effect of nicotine was mimicked by TTX, suggesting the involvement of neuronal mechanisms. This information might be used for evaluating the long-term effects of nicotine and further exploring of how tobacco products interact with bacterial airway infections. Copyright © 2017 the American Physiological Society.

  3. Modulation of long-latency afferent inhibition by the amplitude of sensory afferent volley.

    Science.gov (United States)

    Turco, Claudia V; El-Sayes, Jenin; Fassett, Hunter J; Chen, Robert; Nelson, Aimee J

    2017-07-01

    Long-latency afferent inhibition (LAI) is the inhibition of the transcranial magnetic stimulation (TMS) motor-evoked potentials (MEP) by the sensory afferent volley following electrical stimulation of a peripheral nerve. It is unknown how the activation of sensory afferent fibers relates to the magnitude of LAI. This study investigated the relationship between LAI and the sensory nerve action potentials (SNAP) from the median nerve (MN) and the digital nerves (DN) of the second digit. LAI was obtained by delivering nerve stimulation 200 ms before a TMS pulse delivered over the motor cortex. Experiment 1 assessed the magnitude of LAI following stimulation of the contralateral MN or DN using nerve stimulus intensities relative to the maximum SNAP (SNAP max ) of that nerve and two TMS intensities (0.5- and 1-mV MEP). Results indicate that MN LAI is maximal at ~50% SNAP max , when presumably all sensory afferents are recruited for TMS of 0.5-mV MEP. For DN, LAI appears at ~50% SNAP max and does not increase with further recruitment of sensory afferents. Experiment 2 investigated the magnitude of LAI following ipsilateral nerve stimulation at intensities relative to SNAP max Results show minimal LAI evoked by ipsilateral MN and no LAI following ipsilateral DN stimulation. Implications for future studies investigating LAI include adjusting nerve stimulation to 50% SNAP max to obtain maximal LAI. Additionally, MN LAI can be used as a marker for neurological disease or injury by using a nerve stimulation intensity that can evoke a depth of LAI capable of increasing or decreasing. NEW & NOTEWORTHY This is the first investigation of the relationship between long-latency afferent inhibition (LAI) and the sensory afferent volley. Differences exist between median and digital nerve LAI. For the median nerve, LAI increases until all sensory fibers are presumably recruited. In contrast, digital nerve LAI does not increase with the recruitment of additional sensory fibers but

  4. Arginase attenuates inhibitory nonadrenergic noncholinergic nerve-induced nitric oxide generation and airway smooth muscle relaxation

    NARCIS (Netherlands)

    Maarsingh, H; Tio, MA; Zaagsma, J; Meurs, H

    2005-01-01

    Background: Recent evidence suggests that endogenous arginase activity potentiates airway responsiveness to methacholine by attenuation of agonist-induced nitric oxide (NO) production, presumably by competition with epithelial constitutive NO synthase for the common substrate, L-arginine. Using

  5. The expression profile of acid-sensing ion channel (ASIC) subunits ASIC1a, ASIC1b, ASIC2a, ASIC2b, and ASIC3 in the esophageal vagal afferent nerve subtypes.

    Science.gov (United States)

    Dusenkova, Svetlana; Ru, Fei; Surdenikova, Lenka; Nassenstein, Christina; Hatok, Jozef; Dusenka, Robert; Banovcin, Peter; Kliment, Jan; Tatar, Milos; Kollarik, Marian

    2014-11-01

    Acid-sensing ion channels (ASICs) have been implicated in esophageal acid sensing and mechanotransduction. However, insufficient knowledge of ASIC subunit expression profile in esophageal afferent nerves hampers the understanding of their role. This knowledge is essential because ASIC subunits form heteromultimeric channels with distinct functional properties. We hypothesized that the esophageal putative nociceptive C-fiber nerves (transient receptor potential vanilloid 1, TRPV1-positive) express multiple ASIC subunits and that the ASIC expression profile differs between the nodose TRPV1-positive subtype developmentally derived from placodes and the jugular TRPV1-positive subtype derived from neural crest. We performed single cell RT-PCR on the vagal afferent neurons retrogradely labeled from the esophagus. In the guinea pig, nearly all (90%-95%) nodose and jugular esophageal TRPV1-positive neurons expressed ASICs, most often in a combination (65-75%). ASIC1, ASIC2, and ASIC3 were expressed in 65-75%, 55-70%, and 70%, respectively, of both nodose and jugular TRPV1-positive neurons. The ASIC1 splice variants ASIC1a and ASIC1b and the ASIC2 splice variant ASIC2b were similarly expressed in both nodose and jugular TRPV1-positive neurons. However, ASIC2a was found exclusively in the nodose neurons. In contrast to guinea pig, ASIC3 was almost absent from the mouse vagal esophageal TRPV1-positive neurons. However, ASIC3 was similarly expressed in the nonnociceptive TRPV1-negative (tension mechanoreceptors) neurons in both species. We conclude that the majority of esophageal vagal nociceptive neurons express multiple ASIC subunits. The placode-derived nodose neurons selectively express ASIC2a, known to substantially reduce acid sensitivity of ASIC heteromultimers. ASIC3 is expressed in the guinea pig but not in the mouse vagal esophageal TRPV1-positive neurons, indicating species differences in ASIC expression. Copyright © 2014 the American Physiological Society.

  6. Effects of combined treatment of tadalafil and tamsulosin on bladder dysfunction via the inhibition of afferent nerve activities in a rat model of bladder outlet obstruction.

    Science.gov (United States)

    Furuta, Akira; Suzuki, Yasuyuki; Igarashi, Taro; Koike, Yusuke; Egawa, Shin; Yoshimura, Naoki

    2018-03-08

    To investigate the effects of combined treatment of tadalafil (a phosphodiesterase-5 inhibitor) and tamsulosin (an α 1 -adrenoceptor antagonist) on bladder dysfunction in a rat model of bladder outlet obstruction (BOO). Cystometry was performed in conscious female BOO rats 6 weeks after partially ligation of the urethra. Either tadalafil (0.03, 0.1 and 0.3 mg/kg) or tamsulosin (0.001, 0.003 and 0.01 mg/kg) was cumulatively applied intravenously at 30-min intervals to examine changes in cystometric parameters and blood pressures. Changes in cystometric parameters and blood pressures were also checked when tadalafil (0.3 mg/kg), tamsulosin (0.003 mg/kg) or both were intravenously applied. In BOO rats, application of either tadalafil (0.3 mg/kg) or tamsulosin (0.003, 0.01 mg/kg) alone significantly increased threshold pressures and intercontraction intervals whereas there were no significant changes in other cystometric parameters. In addition, because a significant reduction in blood pressures was detected after the administration of tamsulosin (0.01 mg/kg), tamsulosin at a lower dose (0.003 mg/kg) was used for the combined treatment. The combination therapy of tadalafil and tamsulosin induced a significantly larger rate of increase in intercontraction intervals (1.7 times) compared with monotherapy of either drug (1.3 times each) although the combined therapy did not affect blood pressures. These results suggest that the combination therapy of tadalafil and tamsulosin can induce the additive inhibitory effects on urinary frequency compared with monotherapy, more likely via inhibition of the afferent limb of micturition reflex rather than the efferent function as evidenced by the increases in threshold pressures and intercontraction intervals without affecting bladder contractile function.

  7. Different Mode of Afferents Determines the Frequency Range of High Frequency Activities in the Human Brain: Direct Electrocorticographic Comparison between Peripheral Nerve and Direct Cortical Stimulation.

    Directory of Open Access Journals (Sweden)

    Katsuya Kobayashi

    Full Text Available Physiological high frequency activities (HFA are related to various brain functions. Factors, however, regulating its frequency have not been well elucidated in humans. To validate the hypothesis that different propagation modes (thalamo-cortical vs. cortico-coritcal projections, or different terminal layers (layer IV vs. layer II/III affect its frequency, we, in the primary somatosensory cortex (SI, compared HFAs induced by median nerve stimulation with those induced by electrical stimulation of the cortex connecting to SI. We employed 6 patients who underwent chronic subdural electrode implantation for presurgical evaluation. We evaluated the HFA power values in reference to the baseline overriding N20 (earliest cortical response and N80 (late response of somatosensory evoked potentials (HFA(SEP(N20 and HFA(SEP(N80 and compared those overriding N1 and N2 (first and second responses of cortico-cortical evoked potentials (HFA(CCEP(N1 and HFA(CCEP(N2. HFA(SEP(N20 showed the power peak in the frequency above 200 Hz, while HFA(CCEP(N1 had its power peak in the frequency below 200 Hz. Different propagation modes and/or different terminal layers seemed to determine HFA frequency. Since HFA(CCEP(N1 and HFA induced during various brain functions share a similar broadband profile of the power spectrum, cortico-coritcal horizontal propagation seems to represent common mode of neural transmission for processing these functions.

  8. Ototrauma induces sodium channel plasticity in auditory afferent neurons

    OpenAIRE

    Fryatt, Alistair G.; Mulheran, Mike; Egerton, Julie; Gunthorpe, Martin J.; Grubb, Blair D.

    2011-01-01

    Exposure to intense sound can cause damage to the delicate sensory and neuronal components of the cochlea leading to hearing loss. Such damage often causes the dendrites of the spiral ganglion neurons (SGN), the neurons that provide the afferent innervation of the hair cells, to swell and degenerate thus damaging the synapse. In models of neuropathic pain, axotomy, another form of afferent nerve damage, is accompanied by altered voltage-gated sodium channel (VGSC) expression, leading to neuro...

  9. Cellular mechanisms for presynaptic inhibition of sensory afferents

    DEFF Research Database (Denmark)

    Perrier, Jean-Francois Marie; delgado-lezama, rodolfo; Christensen, Rasmus Kordt

    (DRP) by stimulating one dorsal root and recording another one. In the presence of a low concentration of tetrodotoxin (100nM) nerve impulses are abolished centrally but remain in nociceptive afferents. Under these conditions, a DRP generated by a non-spiking microcircuit remained. In the presence...... with a 2-photon microscope. Stimulation of primary afferents evoked a transient increase in calcium concentration in a subset of cells. The response disappeared after addition of CNQX. This showed that primary afferents activate astrocytes. In a thin slice preparation, we recorded astrocytes with the whole...

  10. How to test for a relative afferent pupillary defect (RAPD

    Directory of Open Access Journals (Sweden)

    David C Broadway

    2012-01-01

    Full Text Available The 'swinging light test' is used to detect a relative afferent pupil defect (RAPD: a means of detecting differences between the two eyes in how they respond to a light shone in one eye at a time. The test can be very useful for detecting unilateral or asymmetrical disease of the retina or optic nerve (but only optic nerve disease that occurs in front of the optic chiasm.

  11. Distribution and sub-types of afferent fibre in the mouse urinary bladder.

    Science.gov (United States)

    Rahnama'i, M S; Biallosterski, B T; Van Kerrebroeck, Ph E V; van Koeveringe, G A; Gillespie, J I; de Wachter, S G

    2017-01-01

    Increased afferent fibre activity contributes to pathological conditions such as the overactive bladder syndrome. Nerve fibres running near the urothelium are considered to be afferent as no efferent system has yet been described. The aim of this study was to identify sub-types of afferent nerve fibres in the mouse bladder wall based on morphological criteria and analyse regional differences. 27 bladders of six month old C57BL/6 mice were removed and tissues were processed for immunohistochemistry. Cryostat sections were cut and stained for Protein Gene Product 9.5 (PGP), calcitonin gene related polypeptide (CGRP), neurofilament (NF), vesicular acetylcholine transporter (VAChT) and neuronal nitric oxide synthase (nNOS). In the sub-urothelium, different types of afferent nerve fibre were found, i.e. immunoreactive (IR) to; CGRP, NF, VAChT, and/or nNOS. At the bladder base, the sub-urothelium was more densely innervated by CGRP-IR and VAChT-IR nerve fibres, then at the lateral wall. NF- and nNOS nerves were sparsely distributed in the sub-urothelium throughout the bladder. At the lateral wall the inner muscle is densely innervated by CGRP-IR nerve fibres. NF, VAChT and nNOS nerves were evenly distributed in the different muscle layers throughout the bladder. Nerve fibre terminals expressing CGRP and NF were found within the extra-mural ganglia at the bladder base. Different types of afferent nerve fibres were identified in the sub-urothelium of the mouse bladder. At the bladder base the sub-urothelium is more densely innervated than the lateral wall by CGRP-IR and VAChT-IR afferent nerve fibres. CGRP and NF afferent nerve fibres in the muscle layer probably relay afferent input to external ganglia located near the bladder base. The identification of different afferent nerves in the sub-urothelium suggests a functional heterogeneity of the afferent nerve fibres in the urinary bladder. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. A new function for ATP: activating cardiac sympathetic afferents during myocardial ischemia.

    Science.gov (United States)

    Fu, Liang-Wu; Longhurst, John C

    2010-12-01

    Myocardial ischemia activates cardiac sympathetic afferents leading to chest pain and reflex cardiovascular responses. Brief myocardial ischemia leads to ATP release in the interstitial space. Furthermore, exogenous ATP and α,β-methylene ATP (α,β-meATP), a P2X receptor agonist, stimulate cutaneous group III and IV sensory nerve fibers. The present study tested the hypothesis that endogenous ATP excites cardiac afferents during ischemia through activation of P2 receptors. Nerve activity of single unit cardiac sympathetic afferents was recorded from the left sympathetic chain or rami communicates (T(2)-T(5)) in anesthetized cats. Single fields of 45 afferents (conduction velocities = 0.25-4.92 m/s) were identified in the left ventricle with a stimulating electrode. Five minutes of myocardial ischemia stimulated 39 of 45 cardiac afferents (8 Aδ, 37 C fibers). Epicardial application of ATP (1-4 μmol) stimulated six ischemically sensitive cardiac afferents in a dose-dependent manner. Additionally, epicardial ATP (2 μmol), ADP (2 μmol), a P2Y agonist, and α,β-meATP (0.5 μmol) significantly activated eight other ischemically sensitive afferents. Third, pyridoxal phosphate-6-azophenyl-2',4'-disulfonic acid, a P2 receptor antagonist, abolished the responses of six afferents to epicardial ATP (2 μmol) and attenuated the ischemia-related increase in activity of seven other afferents by 37%. In the absence of P2 receptor blockade, cardiac afferents responded consistently to repeated application of ATP (n = 6) and to recurrent myocardial ischemia (n = 6). Finally, six ischemia-insensitive cardiac spinal afferents did not respond to epicardial ATP (2-4 μmol), although these afferents did respond to epicardial bradykinin. Taken together, these data indicate that, during ischemia, endogenously released ATP activates ischemia-sensitive, but not ischemia-insensitive, cardiac spinal afferents through stimulation of P2 receptors likely located on the cardiac sensory

  13. Effects of short-term continuous positive airway pressure on myocardial sympathetic nerve function and energetics in patients with heart failure and obstructive sleep apnea: a randomized study.

    Science.gov (United States)

    Hall, Allison B; Ziadi, Maria C; Leech, Judith A; Chen, Shin-Yee; Burwash, Ian G; Renaud, Jennifer; deKemp, Robert A; Haddad, Haissam; Mielniczuk, Lisa M; Yoshinaga, Keiichiro; Guo, Ann; Chen, Li; Walter, Olga; Garrard, Linda; DaSilva, Jean N; Floras, John S; Beanlands, Rob S B

    2014-09-09

    Heart failure with reduced ejection fraction and obstructive sleep apnea (OSA), 2 states of increased metabolic demand and sympathetic nervous system activation, often coexist. Continuous positive airway pressure (CPAP), which alleviates OSA, can improve ventricular function. It is unknown whether this is due to altered oxidative metabolism or presynaptic sympathetic nerve function. We hypothesized that short-term (6-8 weeks) CPAP in patients with OSA and heart failure with reduced ejection fraction would improve myocardial sympathetic nerve function and energetics. Forty-five patients with OSA and heart failure with reduced ejection fraction (left ventricular ejection fraction 35.8±9.7% [mean±SD]) were evaluated with the use of echocardiography and 11C-acetate and 11C-hydroxyephedrine positron emission tomography before and ≈6 to 8 weeks after randomization to receive short-term CPAP (n=22) or no CPAP (n=23). Work metabolic index, an estimate of myocardial efficiency, was calculated as follows: (stroke volume index×heart rate×systolic blood pressure÷Kmono), where Kmono is the monoexponential function fit to the myocardial 11C-acetate time-activity data, reflecting oxidative metabolism. Presynaptic sympathetic nerve function was measured with the use of the 11C-hydroxyephedrine retention index. CPAP significantly increased hydroxyephedrine retention versus no CPAP (Δretention: +0.012 [0.002, 0.021] versus -0.006 [-0.013, 0.005] min(-1); P=0.003). There was no significant change in work metabolic index between groups. However, in those with more severe OSA (apnea-hypopnea index>20 events per hour), CPAP significantly increased both work metabolic index and systolic blood pressure (Penergetics. In those with more severe OSA, CPAP may improve cardiac efficiency. Further outcome-based investigation of the consequences of CPAP is warranted. http://www.clinicaltrials.gov. Unique identifier: NCT00756366. © 2014 American Heart Association, Inc.

  14. Neurophysiological modeling of bladder afferent activity in the rat overactive bladder model.

    Science.gov (United States)

    Choudhary, Mahipal; van Asselt, Els; van Mastrigt, Ron; Clavica, Francesco

    2015-07-01

    The overactive bladder (OAB) is a syndrome-based urinary dysfunction characterized by "urgency, with or without urge incontinence, usually with frequency and nocturia". Earlier we developed a mathematical model of bladder nerve activity during voiding in anesthetized rats and found that the nerve activity in the relaxation phase of voiding contractions was all afferent. In the present study, we applied this mathematical model to an acetic acid (AA) rat model of bladder overactivity to study the sensitivity of afferent fibers in intact nerves to bladder pressure and volume changes. The afferent activity in the filling phase and the slope, i.e., the sensitivity of the afferent fibers to pressure changes in the post-void relaxation phase, were found to be significantly higher in AA than in saline measurements, while the offset (nerve activity at pressure ~0) and maximum pressure were comparable. We have thus shown, for the first time, that the sensitivity of afferent fibers in the OAB can be studied without cutting nerves or preparation of single fibers. We conclude that bladder overactivity induced by AA in rats is neurogenic in origin and is caused by increased sensitivity of afferent sensors in the bladder wall.

  15. Possible role of afferent autonomic signals in abdominal organs in anorexic and cardiovascular responses to nicotine injection in rats.

    Science.gov (United States)

    Yagi, Shintaro; Tanida, Mamoru; Satomi, Jun

    2015-05-27

    Smoking generally causes an increase in nicotine levels in the blood, affecting the brain components, such as the hypothalamus (feeding-related area) or the brain stem (cardiovascular control area). In terms of nicotine transmission to the brain, a new insight that the afferent vagal nerve in the liver is important for sensing increased nicotine levels in the blood and informing the brain was reported in an experiment with rats. However, it has not been clarified whether the afferent autonomic nerve system is implicated in feeding and cardiovascular responses to nicotine. Here, we examined the possible role of afferent autonomic nerve transmission in rats in regulating feeding behavior and cardiovascular functions by nicotine. An intravenous injection of nicotine dose dependently increased the blood pressure (BP) in urethane-anesthetized rats; high nicotine doses also led to an increase in BP in conscious rats. Further, an intravenous injection of nicotine for 3 days reduced food intake and body weight gain in rats. The weight-reducing action of intravenous nicotine was abolished by blocking the afferent sympathetic signals in the abdominal organs, but not the vagal nerve signals. Moreover, the hypertensive action of nicotine was not abolished either by afferent sympathectomy or by vagotomy. Thus, these data suggest that nicotine injected into the vein acts on the afferent sympathetic nerve in the abdominal organs and transmits signals to the brain for reducing body weight, but not for suppressing appetite or increasing BP.

  16. NEUROTROPHIN MEDIATION OF ALLERGIC AIRWAYS RESPONSES TO INHALED DIESEL PARTICLES IN MICE

    Science.gov (United States)

    Neurotrophins, including nerve growth factor (NGF) partially mediate many features of allergic airways disease including airway hyper-responsiveness. Diesel exhaust particulates (DEP) associated with the combustion of diesel fuel exacerbate many of these allergic airways respons...

  17. Anatomy and physiology of phrenic afferent neurons.

    Science.gov (United States)

    Nair, Jayakrishnan; Streeter, Kristi A; Turner, Sara M F; Sunshine, Michael D; Bolser, Donald C; Fox, Emily J; Davenport, Paul W; Fuller, David D

    2017-12-01

    Large-diameter myelinated phrenic afferents discharge in phase with diaphragm contraction, and smaller diameter fibers discharge across the respiratory cycle. In this article, we review the phrenic afferent literature and highlight areas in need of further study. We conclude that 1 ) activation of both myelinated and nonmyelinated phrenic sensory afferents can influence respiratory motor output on a breath-by-breath basis; 2 ) the relative impact of phrenic afferents substantially increases with diaphragm work and fatigue; 3 ) activation of phrenic afferents has a powerful impact on sympathetic motor outflow, and 4 ) phrenic afferents contribute to diaphragm somatosensation and the conscious perception of breathing. Much remains to be learned regarding the spinal and supraspinal distribution and synaptic contacts of myelinated and nonmyelinated phrenic afferents. Similarly, very little is known regarding the potential role of phrenic afferent neurons in triggering or modulating expression of respiratory neuroplasticity. Copyright © 2017 the American Physiological Society.

  18. Functional recovery of anterior semicircular canal afferents following hair cell regeneration in birds

    Science.gov (United States)

    Boyle, Richard; Highstein, Stephen M.; Carey, John P.; Xu, Jinping

    2002-01-01

    Streptomycin sulfate (1.2 g/kg i.m.) was administered for 5 consecutive days to 5-7-day-old white Leghorn chicks; this causes damage to semicircular canal hair cells that ultimately regenerate to reform the sensory epithelium. During the recovery period, electrophysiological recordings were taken sequentially from anterior semicircular canal primary afferents using an indentation stimulus of the canal that has been shown to mimic rotational stimulation. Chicks were assigned to an early (14-18 days; n = 8), intermediate (28-34 days; n = 5), and late (38-58 days; n = 4) period based on days after treatment. Seven untreated chicks, 15-67 days old, provided control data. An absence of background and indent-induced discharge was the prominent feature of afferents in the early period: only "silent" afferents were encountered in 5/8 experiments. In several of these chicks, fascicles of afferent fibers were seen extending up to the epithelium that was void of hair cells, and intra- and extracellular biocytin labeling revealed afferent processes penetrating into the supporting cell layer of the crista. In 3/8 chicks 74 afferents could be characterized, and they significantly differed from controls (n = 130) by having a lower discharge rate and a negligible response to canal stimulation. In the intermediate period there was considerable variability in discharge properties of 121 afferents, but as a whole the number of "silent" fibers in the canal nerve diminished, the background rate increased, and a response to canal stimulation detected. Individually biocytin-labeled afferents had normal-appearing terminal specializations in the sensory epithelium by 28 days poststreptomycin. In the late period, afferents (n = 58) remained significantly different from controls in background discharge properties and response gain. The evidence suggests that a considerable amount of variability exists between chicks in the return of vestibular afferent function following ototoxic injury and

  19. Finite element modeling and in vivo analysis of electrode configurations for selective stimulation of pudendal afferent fibers

    Directory of Open Access Journals (Sweden)

    Grill Warren M

    2010-05-01

    Full Text Available Abstract Background Intraurethral electrical stimulation (IES of pudendal afferent nerve fibers can evoke both excitatory and inhibitory bladder reflexes in cats. These pudendovesical reflexes are a potential substrate for restoring bladder function in persons with spinal cord injury or other neurological disorders. However, the complex distribution of pudendal afferent fibers along the lower urinary tract presents a challenge when trying to determine the optimal geometry and position of IES electrodes for evoking these reflexes. This study aimed to determine the optimal intraurethral electrode configuration(s and locations for selectively activating targeted pudendal afferents to aid future preclinical and clinical investigations. Methods A finite element model (FEM of the male cat urethra and surrounding structures was generated to simulate IES with a variety of electrode configurations and locations. The activating functions (AFs along pudendal afferent branches innervating the cat urethra were determined. Additionally, the thresholds for activation of pudendal afferent branches were measured in α-chloralose anesthetized cats. Results Maximum AFs evoked by intraurethral stimulation in the FEM and in vivo threshold intensities were dependent on stimulation location and electrode configuration. Conclusions A ring electrode configuration is ideal for IES. Stimulation near the urethral meatus or prostate can activate the pudendal afferent fibers at the lowest intensities, and allowed selective activation of the dorsal penile nerve or cranial sensory nerve, respectively. Electrode location was a more important factor than electrode configuration for determining stimulation threshold intensity and nerve selectivity.

  20. The pattern of trunk lateral line afferents and efferents in the rainbow trout (Salmo gairdneri)

    NARCIS (Netherlands)

    Schellart, N. A.; Prins, M.; Kroese, A. B.

    1992-01-01

    The primary projections of the mechanosensory posterior lateral line nerve of the rainbow trout Salmo gairdneri, a teleost without lateral line specializations, were studied by applying horseradish peroxidase (HRP). The afferents project nearly exclusively to the nucleus medialis and a small nucleus

  1. Tumors of the optic nerve

    DEFF Research Database (Denmark)

    Lindegaard, Jens; Heegaard, Steffen

    2009-01-01

    A variety of lesions may involve the optic nerve. Mainly, these lesions are inflammatory or vascular lesions that rarely necessitate surgery but may induce significant visual morbidity. Orbital tumors may induce proptosis, visual loss, relative afferent pupillary defect, disc edema and optic...... atrophy, but less than one-tenth of these tumors are confined to the optic nerve or its sheaths. No signs or symptoms are pathognomonic for tumors of the optic nerve. The tumors of the optic nerve may originate from the optic nerve itself (primary tumors) as a proliferation of cells normally present...... in the nerve (e.g., astrocytes and meningothelial cells). The optic nerve may also be invaded from tumors originating elsewhere (secondary tumors), invading the nerve from adjacent structures (e.g., choroidal melanoma and retinoblastoma) or from distant sites (e.g., lymphocytic infiltration and distant...

  2. CELIOMESENTERIC AFFERENCE OF THE DORSOLUMBAR NEUROMERS IN HORSE

    Directory of Open Access Journals (Sweden)

    CARMEN BERGHES

    2008-05-01

    Full Text Available The frequent variability of the splanchnic branches in all species creates difficulties both in carrying out physiological experiments and, particularly, in some specifications concerning the neuroglandular relations in the mesenteric area in horses. A total of 32 dissections were conducted on fresh, non-mummified corpses and were accompanied by comparative evaluations. The nervous formations were tracked up to the limit of visibility with the magnifying glass of 15 dioptres. To make possible the differentiation of the nervous fibres, the arteries were injected with a red dye. The ganglion formations were investigated with histological methods of differentiation. The dissection also revealed that the efferent fibres which approach the celiomesenteric plexus do not belong, as thought, only to the large and small splanchnic, but also to the lumbar splanchnic nerves which were regarded as being small accessory splanchnic nerves. According to these wrong data, the renosuprarenal plexus would only include abdominal splanchnic afferences and not also lumbar splanchnic afferences, as it actually happens. Speaking of horses, the data reveal the existence of peculiarities regarding the dorsolumbar efferences of the celiomesenteric plexus which detach in most cases from the interganglionar connectives and not directly from the paravertebral ganglia. Another observation is related to the existence of the renal nerves (one or two small fibres, nerves which detach from the abdominal splanchnic nerves which, crossing over the lateral side of the suprarenal gland seem to link it to the kidneys. The existence of postrenal nervous loops might provide evidence, if not on the ontogeny, at least on the way of postembryonic migration of this organ.

  3. Relief of fecal incontinence by sacral nerve stimulation linked to focal brain activation

    DEFF Research Database (Denmark)

    Lundby, Lilli; Møller, Arne; Buntzen, Steen

    2011-01-01

    This study aimed to test the hypothesis that sacral nerve stimulation affects afferent vagal projections to the central nervous system associated with frontal cortex activation in patients with fecal incontinence.......This study aimed to test the hypothesis that sacral nerve stimulation affects afferent vagal projections to the central nervous system associated with frontal cortex activation in patients with fecal incontinence....

  4. Precise temporal association between cortical potentials evoked by motor imagination and afference induces cortical plasticity.

    Science.gov (United States)

    Mrachacz-Kersting, Natalie; Kristensen, Signe Rom; Niazi, Imran Khan; Farina, Dario

    2012-04-01

    In monkeys, the repeated activation of somatosensory afferents projecting onto the motor cortex (M1) has a pivotal role in motor skill learning. Here we investigate if sensory feedback that is artificially generated at specific times during imagination of a dorsiflexion task leads to reorganization of the human M1. The common peroneal nerve was stimulated to generate an afferent volley timed to arrive during specific phases of the cortical potential generated when a movement was imagined (50 repetitions). The change in the output of M1 was quantified by applying single transcranial magnetic stimuli to the area of M1 controlling the tibialis anterior muscle. The results demonstrated that the concomitance between the cognitive process of movement (motor imagination) and the ascending volley due to the peripheral nerve stimulation can lead to significant increases in cortical excitability. These increases were critically dependent on the timing between the peripherally generated afferent volley and the cortical potential generated during the imagined movement. Only if the afferent volley arrived during the peak negative deflection of the potential, were significant alterations in motor cortical output attained. These results demonstrate that an artificially generated signal (the peripheral afferent volley) can interact with a physiologically generated signal in humans leading to plastic changes within the M1, the final output stage for movement generation within the human brain. The results presented may have implications in systems for artificially inducing cortical plasticity in patients with motor impairments (neuromodulation).

  5. Sensory input to the central nervous system from the lungs and airways: A prominent role for purinergic signalling via P2X2/3 receptors.

    Science.gov (United States)

    Adriaensen, Dirk; Brouns, Inge; Timmermans, Jean-Pierre

    2015-09-01

    Specific subpopulations of lung-related primary afferent neurons in dorsal root and vagal sensory ganglia have been reported to express P2X2 and P2X3 receptors both in the neuronal cell bodies and in their peripheral terminals. The afferent innervation of airways and lungs is organised as sensory receptor structures, of which at least seven types with a vagal origin and two with a spinal origin have been reported. In view of the recently suggested therapeutic promise of ATP antagonism - specifically at P2X3 receptor expressing nociceptive fibres - in respiratory disorders, the present work focusses on four distinct populations of pulmonary sensory receptors that have so far been reported to express P2X2/3 receptors. Three of them originate from myelinated nerve fibres that display similar mechanosensor-like morphological and neurochemical characteristics. Two of the latter concern vagal nodose sensory fibres, either related to pulmonary neuroepithelial bodies (NEBs), or giving rise to smooth muscle-associated airway receptors (SMARs); the third gives rise to visceral pleura receptors (VPRs) and most likely arises from dorsal root ganglia. The fourth population concerns C-fibre receptors (CFRs) that also derive from neuronal cell bodies located in vagal nodose ganglia. Although the majority of the airway- and lung-related sensory receptors that express P2X2/3 receptors apparently do not belong to accepted nociceptive populations, these data definitely point out that ATP may be an important player in the physiological transduction of different lung-related afferent signals from the periphery to the CNS. The observed variety within the populations of pulmonary sensory receptors that express P2X2/3 receptors argues for a critical and careful interpretation of the functional data. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Anatomy and physiology of the afferent visual system.

    Science.gov (United States)

    Prasad, Sashank; Galetta, Steven L

    2011-01-01

    The efficient organization of the human afferent visual system meets enormous computational challenges. Once visual information is received by the eye, the signal is relayed by the retina, optic nerve, chiasm, tracts, lateral geniculate nucleus, and optic radiations to the striate cortex and extrastriate association cortices for final visual processing. At each stage, the functional organization of these circuits is derived from their anatomical and structural relationships. In the retina, photoreceptors convert photons of light to an electrochemical signal that is relayed to retinal ganglion cells. Ganglion cell axons course through the optic nerve, and their partial decussation in the chiasm brings together corresponding inputs from each eye. Some inputs follow pathways to mediate pupil light reflexes and circadian rhythms. However, the majority of inputs arrive at the lateral geniculate nucleus, which relays visual information via second-order neurons that course through the optic radiations to arrive in striate cortex. Feedback mechanisms from higher cortical areas shape the neuronal responses in early visual areas, supporting coherent visual perception. Detailed knowledge of the anatomy of the afferent visual system, in combination with skilled examination, allows precise localization of neuropathological processes and guides effective diagnosis and management of neuro-ophthalmic disorders. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Afferent Endocrine Control of Eating

    DEFF Research Database (Denmark)

    Langhans, Wolfgang; Holst, Jens Juul

    2016-01-01

    The afferent endocrine factors that control eating can be separated into different categories. One obvious categorization is by the time course of their effects, with long-term factors that signal adiposity and short-term factors that operate within the time frame of single meals. The second...... obvious categorization is by the origin of the endocrine signalling molecules. The level of knowledge concerning the physiological mechanisms and relevance of the hormones that are implicated in the control of eating is clearly different. With the accumulating knowledge about the hormones' actions......, various criteria have been developed for when the effect of a hormone can be considered 'physiologic'. This chapter treats the hormones separately and categorizes them by origin. It discusses ALL hormones that are implicated in eating control such as Gastrointestinal (GI) hormone and glucagon-like peptide...

  8. Interaction between TRPA1 and TRPV1: Synergy on pulmonary sensory nerves.

    Science.gov (United States)

    Lee, Lu-Yuan; Hsu, Chun-Chun; Lin, Yu-Jung; Lin, Ruei-Lung; Khosravi, Mehdi

    2015-12-01

    Transient receptor potential ankyrin type 1 (TRPA1) and vanilloid type 1 (TRPV1) receptors are co-expressed in vagal pulmonary C-fiber sensory nerves. Because both these ligand-gated non-selective cation channels are sensitive to a number of endogenous inflammatory mediators, it is highly probable that they can be activated simultaneously during airway inflammation. Studies were carried out to investigate whether there is an interaction between these two polymodal transducers upon simultaneous activation, and how it modulates the activity of vagal pulmonary C-fiber sensory nerves. Our studies showed a distinct potentiating effect induced abruptly by simultaneous activations of TRPA1 and TRPV1 by their respective selective agonists, allyl isothiocyanate (AITC) and capsaicin (Cap), at near-threshold concentrations. This synergistic effect was demonstrated in the studies of single-unit recording of vagal bronchopulmonary C-fiber afferents and the reflex responses elicited by activation of these afferents in intact animals, as well as in the isolated nodose and jugular bronchopulmonary sensory neurons. This potentiating effect was absent when either AITC or Cap was replaced by non-TRPA1 and non-TRPV1 chemical activators of these neurons, demonstrating the selectivity of the interaction between these two TRP channels. Furthermore, the synergism was dependent upon the extracellular Ca(2+), and the rapid onset of the action further suggests that the interaction probably occurred locally at the sites of these channels. These findings suggest that the TRPA1-TRPV1 interaction may play an important role in regulating the function and excitability of pulmonary sensory neurons during airway inflammation, but the mechanism underlying this positive interaction is not yet fully understood. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Modulation of jaw muscle spindle afferent activity following intramuscular injections with hypertonic saline.

    Science.gov (United States)

    Ro, J Y; Capra, N F

    2001-05-01

    Transient noxious chemical stimulation of small diameter muscle afferents modulates jaw movement-related responses of caudal brainstem neurons. While it is likely that the effect is mediated from the spindle afferents in the mesencephalic nucleus (Vmes) via the caudally projecting Probst's tract, the mechanisms of pain induced modulations of jaw muscle spindle afferents is not known. In the present study, we tested the hypothesis that jaw muscle nociceptors gain access to muscle spindle afferents in the same muscle via central mechanisms and alter their sensitivity. Thirty-five neurons recorded from the Vmes were characterized as muscle spindle afferents based on their responses to passive jaw movements, muscle palpation, and electrical stimulation of the masseter nerve. Each cell was tested by injecting a small volume (250 microl) of either 5% hypertonic and/or isotonic saline into the receptor-bearing muscle. Twenty-nine units were tested with 5% hypertonic saline, of which 79% (23/29) showed significant modulation of mean firing rates (MFRs) during one or more phases of ramp-and-hold movements. Among the muscle spindle primary-like units (n = 12), MFRs of 4 units were facilitated, five reduced, two showed mixed responses and one unchanged. In secondary-like units (n = 17), MFRs of 9 were facilitated, three reduced and five unchanged. Thirteen units were tested with isotonic saline, of which 77% showed no significant changes of MFRs. Further analysis revealed that the hypertonic saline not only affected the overall output of muscle spindle afferents, but also increased the variability of firing and altered the relationship between afferent signal and muscle length. These results demonstrated that activation of muscle nociceptors significantly affects proprioceptive properties of jaw muscle spindles via central neural mechanisms. The changes can have deleterious effects on oral motor function as well as kinesthetic sensibility.

  10. Sensitization of group III and IV muscle afferents in mouse after ischemia and reperfusion injury

    Science.gov (United States)

    Ross, Jessica L.; Queme, Luis F.; Shank, Aaron T.; Hudgins, Renita C.; Jankowski, Michael P.

    2014-01-01

    Ischemic myalgia is a unique type of muscle pain in the patient population. The role that discrete muscle afferent subpopulations play in the generation of pain during ischemic events, however, has yet to be determined. Using two brachial artery occlusion models to compare prolonged ischemia or transient ischemia with reperfusion of the muscles, we found that both injuries caused behavioral decrements in grip strength, as well as increased spontaneous pain behaviors. Using our ex vivo forepaw muscles, median and ulnar nerves, dorsal root ganglion (DRG), and spinal cord recording preparation, we found after both prolonged and transient ischemia, that there was a significant increase in the number of afferents that responded to both noxious and non-noxious36 chemical (lactate, ATP, varying pH) stimulation of the muscles compared to uninjured controls. However, we found an increase in firing to heat stimuli specifically in muscle afferents during prolonged ischemia, but a distinct increase in afferent firing to non-noxious chemicals and decreased mechanical thresholds after transient ischemia. The unique changes in afferent function observed also corresponded with distinct patterns of gene expression in the DRGs. Thus the development of ischemic myalgia may be generated by unique afferent based mechanisms during prolonged and transient ischemia. Perspective This study analyzes the response properties of thinly myelinated group III and unmyelinated group IV muscle afferents during prolonged and transient ischemia in addition to pain behaviors and alterations in DRG gene expression in mouse. Results suggest that mechanisms of pain generation during prolonged ischemia may be different from ischemia/reperfusion. PMID:25245401

  11. Mechanoreceptor afferent activity compared with receptor field dimensions and pressure changes in feline urinary bladder.

    Science.gov (United States)

    Downie, J W; Armour, J A

    1992-11-01

    The relationship between vesical mechanoreceptor field dimensions and afferent nerve activity recorded in pelvic plexus nerve filaments was examined in chloralose-anesthetized cats. Orthogonal receptor field dimensions were monitored with piezoelectric ultrasonic crystals. Reflexly generated bladder contractile activity made measurements difficult, therefore data were collected from cats subjected to actual sacral rhizotomy. Afferent activity was episodic and was initiated at different pressure and receptor field dimension thresholds. Maximum afferent activity did not correlate with maximum volume or pressure. Furthermore, activity was not linearly related to intravesical pressure, receptor field dimensions, or calculated wall tension. Pressure-length hysteresis of the receptor fields occurred. The responses of identified afferent units and their associated receptor field dimensions to brief contractions elicited by the ganglion stimulant 1,1-dimethyl-4-phenylpiperazinium iodide (2.5-20 micrograms i.a.), studied under constant volume or constant pressure conditions, are compatible with bladder mechanoreceptors behaving as tension receptors. Because activity generated by bladder mechanoreceptors did not correlate in a simple fashion with intravesical pressure or receptor field dimensions, it is concluded that such receptors are influenced by the viscoelastic properties of the bladder wall. Furthermore, as a result of the heterogeneity of the bladder wall, receptor field tension appears to offer a more precise relationship with the activity of bladder wall mechanoreceptors than does intravesical pressure.

  12. Catheter-Based Renal Nerve Ablation and Centrally Generated Sympathetic Activity in Difficult-to-Control Hypertensive Patients: Prospective Case Series

    NARCIS (Netherlands)

    Brinkmann, J.; Heusser, K.; Schmidt, B.M.; Menne, J.; Klein, G.; Bauersachs, J.; Haller, H.; Sweep, F.C.; Diedrich, A.; Jordan, J.; Tank, J.

    2012-01-01

    Endovascular renal nerve ablation has been developed to treat resistant hypertension. In addition to lowering efferent renal sympathetic activation, the intervention may attenuate central sympathetic outflow through decreased renal afferent nerve traffic, as evidenced by a recent case report. We

  13. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Airway Clearance Airway Clearance Techniques (ACTs) There are different ways to clear your airways. Most are easy ... to loosen mucus from airway walls. See how different airway clearance techniques work to help you clear ...

  14. Peripheral afferent mechanisms underlying acupuncture inhibition of cocaine behavioral effects in rats.

    Directory of Open Access Journals (Sweden)

    Seol Ah Kim

    Full Text Available Administration of cocaine increases locomotor activity by enhancing dopamine transmission. To explore the peripheral mechanisms underlying acupuncture treatment for drug addiction, we developed a novel mechanical acupuncture instrument (MAI for objective mechanical stimulation. The aim of this study was to evaluate whether acupuncture inhibition of cocaine-induced locomotor activity is mediated through specific peripheral nerves, the afferents from superficial or deep tissues, or specific groups of nerve fibers. Mechanical stimulation of acupuncture point HT7 with MAI suppressed cocaine-induced locomotor activity in a stimulus time-dependent manner, which was blocked by severing the ulnar nerve or by local anesthesia. Suppression of cocaine-induced locomotor activity was elicited after HT7 stimulation at frequencies of either 50 (for Meissner corpuscles or 200 (for Pacinian corpuscles Hz and was not affected by block of C/Aδ-fibers in the ulnar nerve with resiniferatoxin, nor generated by direct stimulation of C/Aδ-fiber afferents with capsaicin. These findings suggest that HT7 inhibition of cocaine-induced locomotor activity is mediated by A-fiber activation of ulnar nerve that originates in superficial and deep tissue.

  15. Presynaptic control of group Ia afferents in relation to acquisition of a visuo-motor skill in healthy humans

    DEFF Research Database (Denmark)

    Perez, Monica A.; Lungholt, Bjarke K.S.; Nielsen, Jens Bo

    2005-01-01

    Sensory information continuously converges on the spinal cord during a variety of motor behaviours. Here, we examined presynaptic control of group Ia afferents in relation to acquisition of a novel motor skill. We tested whether repetition of two motor tasks with different degrees of difficulty...... of the monosynaptic Ia facilitation of the soleus H-reflex evoked by femoral nerve stimulation. The D1 inhibition was increased and the femoral nerve facilitation was decreased following the visuo-motor skill task, suggesting an increase in presynaptic inhibition of Ia afferents. No changes were observed...... in the disynaptic reciprocal Ia inhibition. Somatosensory evoked potentials (SEPs) evoked by stimulation of the tibial nerve (TN) were also unchanged, suggesting that transmission in ascending pathways was unaltered following the visuo-motor skill task. Together these observations suggest that a selective...

  16. Detection thresholds of macaque otolith afferents.

    Science.gov (United States)

    Yu, Xiong-Jie; Dickman, J David; Angelaki, Dora E

    2012-06-13

    The vestibular system is our sixth sense and is important for spatial perception functions, yet the sensory detection and discrimination properties of vestibular neurons remain relatively unexplored. Here we have used signal detection theory to measure detection thresholds of otolith afferents using 1 Hz linear accelerations delivered along three cardinal axes. Direction detection thresholds were measured by comparing mean firing rates centered on response peak and trough (full-cycle thresholds) or by comparing peak/trough firing rates with spontaneous activity (half-cycle thresholds). Thresholds were similar for utricular and saccular afferents, as well as for lateral, fore/aft, and vertical motion directions. When computed along the preferred direction, full-cycle direction detection thresholds were 7.54 and 3.01 cm/s(2) for regular and irregular firing otolith afferents, respectively. Half-cycle thresholds were approximately double, with excitatory thresholds being half as large as inhibitory thresholds. The variability in threshold among afferents was directly related to neuronal gain and did not depend on spike count variance. The exact threshold values depended on both the time window used for spike count analysis and the filtering method used to calculate mean firing rate, although differences between regular and irregular afferent thresholds were independent of analysis parameters. The fact that minimum thresholds measured in macaque otolith afferents are of the same order of magnitude as human behavioral thresholds suggests that the vestibular periphery might determine the limit on our ability to detect or discriminate small differences in head movement, with little noise added during downstream processing.

  17. Identification of bladder and colon afferents in the nodose ganglia of male rats

    Science.gov (United States)

    Herrity, April N.; Rau, Kristofer K.; Petruska, Jeffrey C.; Stirling, David P.; Hubscher, Charles H.

    2014-01-01

    The sensory neurons innervating the urinary bladder and distal colon project to similar regions of the central nervous system and often are affected simultaneously by various diseases and disorders, including spinal cord injury. Anatomical and physiological commonalities between the two organs involve the participation of shared spinal-derived pathways, enabling mechanisms of communication between the bladder and colon. Prior electrophysiological data from our lab suggests that the bladder also may receive sensory innervation from a non-spinal source through the vagus nerve, which innervates the distal colon as well. The present study therefore aimed to determine if anatomical evidence exists for vagal innervation of the male rat urinary bladder and assess whether those vagal afferents also innervate the colon. Additionally, the relative contribution to bladder and colon sensory innervation of spinal and vagal sources was determined. Using lipophilic tracers, neurons that innervated the bladder and colon in both the nodose ganglia (NG) and L6/S1 and L1/L2 dorsal root ganglia (DRG) were quantified. Some single vagal and spinal neurons provided dual innervation to both organs. The proportions of NG afferents labeled from the bladder did not differ from spinal afferents labeled from the bladder when considering the collective population of total neurons from either group. Our results demonstrate evidence for vagal innervation of the bladder and colon and suggest that dichotomizing vagal afferents may provide a neural mechanism for cross-talk between the organs. PMID:24845615

  18. Rimonabant induced anorexia in rodents is not mediated by vagal or sympathetic gut afferents.

    Science.gov (United States)

    Madsen, Andreas N; Jelsing, Jacob; van de Wall, Esther H E M; Vrang, Niels; Larsen, Philip J; Schwartz, Gary J

    2009-01-02

    The selective CB1 receptor antagonist rimonabant is a novel weight control agent. Although CB1 receptors and binding sites are present in both the rodent central and peripheral nervous systems, including the afferent vagus nerve, the role of gut afferents in mediating anorexia following CB1R blockade is still debated. In the present study we examined rimonabant-induced anorexia in male C57BL/6J mice with subdiaphragmatic vagotomy (VGX) as well as in male Sprague-Dawley rats subjected to either subdiaphragmatic vagal deafferentation (SDA) alone or in combination with a complete celiac-superior mesenteric ganglionectomy (CGX). Irrespective of the operational procedure, rimonabant (10mg/kg) effectively reduced standard chow as well as palatable diet (ensure) intake. In conclusion, the data clearly demonstrate that neither vagal gut afferents, nor gut afferents traveling via the sympathetic nervous system, are required for rimonabant to inhibit food intake leading to the hypothesis that centrally located CB1 receptors are the prime mediators of rimonabant-induced anorexia.

  19. Inhibitory mechanisms following electrical stimulation of tendon and cutaneous afferents in the lower limb.

    Science.gov (United States)

    Khan, Serajul I; Burne, John A

    2010-01-13

    Electrical stimulation of the Achilles tendon (TES) produced strong reflex depression (duration>250 ms) of a small background contraction in both heads of gastrocnemius (GA) via large diameter electrodes localized to the tendon. The inhibitory responses were produced without electrical (M wave) or mechanical (muscle twitch) signs of direct muscle stimulation. In this study, the contribution of presynaptic and postsynaptic mechanisms to the depression was investigated by studying conditioning effects of tendon afferent stimulation on the mechanical tendon reflex (TR) and magnetic motor evoked potential (MEP). TES completely inhibited the TR over an ISI of 300 ms that commenced before and continued during and after the period of voluntary EMG depression. Tendon afferent conditioning stimuli also partially inhibited the MEP, but over a short time course confined to the period of voluntary EMG depression. The strength and extended time course of tendon afferent conditioning of the TR and its failure to produce a similar depression of the MEP are consistent with a mechanism involving presynaptic inhibition of Ia terminals. Cutaneous (sural nerve) afferent conditioning partially inhibited the TR and MEP over a short time course (ISI origin of cutaneous inhibition of the motoneurons.

  20. Myelinated Afferents Are Involved in Pathology of the Spontaneous Electrical Activity and Mechanical Hyperalgesia of Myofascial Trigger Spots in Rats

    Directory of Open Access Journals (Sweden)

    Fei Meng

    2015-01-01

    Full Text Available Myofascial trigger points (MTrPs are common causes for chronic pain. Myelinated afferents were considered to be related with muscular pain, and our clinical researches indicated they might participate in the pathology of MTrPs. Here, we applied myofascial trigger spots (MTrSs, equal to MTrPs in human of rats to further investigate role of myelinated afferents. Modified pyridine-silver staining revealed more nerve endings at MTrSs than non-MTrSs (P0.05. 30 min after the injection, MPTs at MTrSs were significantly lower than those of non-MTrSs (P<0.01. Therefore, we concluded that proliferated myelinated afferents existed at MTrSs, which were closely related to pathology of SEA and mechanical hyperalgesia of MTrSs.

  1. Rimonabant induced anorexia in rodents is not mediated by vagal or sympathetic gut afferents

    DEFF Research Database (Denmark)

    Madsen, Andreas Nygaard; Jelsing, Jacob; van de Wall, Esther H E M

    2009-01-01

    The selective CB1 receptor antagonist rimonabant is a novel weight control agent. Although CB1 receptors and binding sites are present in both the rodent central and peripheral nervous systems, including the afferent vagus nerve, the role of gut afferents in mediating anorexia following CB1R...... blockade is still debated. In the present study we examined rimonabant-induced anorexia in male C57BL/6J mice with subdiaphragmatic vagotomy (VGX) as well as in male Sprague-Dawley rats subjected to either subdiaphragmatic vagal deafferentation (SDA) alone or in combination with a complete celiac...... system, are required for rimonabant to inhibit food intake leading to the hypothesis that centrally located CB1 receptors are the prime mediators of rimonabant-induced anorexia....

  2. Role of transient receptor potential vanilloid 1 in the modulation of airway smooth muscle tone and calcium handling.

    Science.gov (United States)

    Yocum, Gene T; Chen, Jun; Choi, Christine H; Townsend, Elizabeth A; Zhang, Yi; Xu, Dingbang; Fu, Xiao W; Sanderson, Michael J; Emala, Charles W

    2017-06-01

    Asthma is a common disorder characterized, in part, by airway smooth muscle (ASM) hyperresponsiveness. Transient receptor potential vanilloid 1 (TRPV1) is a nonselective cation channel expressed on airway nerve fibers that modulates afferent signals, resulting in cough, and potentially bronchoconstriction. In the present study, the TRPV1 transcript was detected by RT-PCR in primary cultured human ASM cells, and the TRPV1 protein was detected in ASM of human trachea by immunohistochemistry. Proximity ligation assays suggest that TRPV1 is expressed in the sarcoplasmic reticulum membrane of human ASM cells in close association with sarco/endoplasmic reticulum Ca 2+ -ATPase-2. In guinea pig tracheal ring organ bath experiments, the TRPV1 agonist capsaicin led to ASM contraction, but this contraction was significantly attenuated by the sodium channel inhibitor bupivacaine ( n = 4, P antagonist GR-159897 ( n = 4, P antagonist capsazepine inhibited the maintenance phase of an acetylcholine-induced contraction ( n = 4, P calcium entry in mouse ASM cells in PCLS ( n = 4-7, P = nonsignificant), it did inhibit calcium oscillations ( n = 3, P calcium oscillations. Copyright © 2017 the American Physiological Society.

  3. Distinct target cell-dependent forms of short-term plasticity of the central visceral afferent synapses of the rat

    Directory of Open Access Journals (Sweden)

    Watabe Ayako M

    2010-10-01

    Full Text Available Abstract Background The visceral afferents from various cervico-abdominal sensory receptors project to the dorsal vagal complex (DVC, which is composed of the nucleus of the solitary tract (NTS, the area postrema and the dorsal motor nucleus of the vagus nerve (DMX, via the vagus and glossopharyngeal nerves and then the solitary tract (TS in the brainstem. While the excitatory transmission at the TS-NTS synapses shows strong frequency-dependent suppression in response to repeated stimulation of the afferents, the frequency dependence and short-term plasticity at the TS-DMX synapses, which also transmit monosynaptic information from the visceral afferents to the DVC neurons, remain largely unknown. Results Recording of the EPSCs activated by paired or repeated TS stimulation in the brainstem slices of rats revealed that, unlike NTS neurons whose paired-pulse ratio (PPR is consistently below 0.6, the distribution of the PPR of DMX neurons shows bimodal peaks that are composed of type I (PPR, 0.6-1.5; 53% of 120 neurons recorded and type II (PPR, Conclusions These two general types of short-term plasticity might contribute to the differential activation of distinct vago-vagal reflex circuits, depending on the firing frequency and type of visceral afferents.

  4. Convergence of meningeal and facial afferents onto trigeminal brainstem neurons: an electrophysiological study in rat and man.

    Science.gov (United States)

    Ellrich, J; Andersen, O K; Messlinger, K; Arendt-Nielsen, L

    1999-09-01

    Headache is often accompanied by referred pain in the face. This phenomenon is probably due to a convergence of afferent inputs from the meninges and the face onto central trigeminal neurons within the medullary dorsal horn (MDH). The possible existence and extent of this convergence was examined in rat and man. MDH neurons activated by stimulation of the parietal meninges were tested for convergent tactile and noxious mechanical input from all three facial branches of the trigeminal nerve. All 21 units with meningeal input could also be activated by facial stimuli. Brush stimuli applied to the supraorbital nerve area activated 86%, to the infraorbital nerve area 29%, and to the mental nerve area none of the units. Pinch stimuli applied to the supraorbital nerve area activated 95%, to the infraorbital nerve area 86%, and to the mental nerve area 52% of the units. The results suggest convergence of meningeal and facial inputs concentrated on the supraorbital nerve in rat. In man convergence was examined by probing neuronal excitability of MDH applying the blink reflex (BR) during Valsalva maneuver which probably increases intracranial pressure. The BR evoked by supraorbital nerve stimulation remained unchanged, while the BR evoked by mental nerve stimulation was significantly facilitated. This facilitation may be due to convergence of meningeal and facial inputs onto trigeminal neurons in man.

  5. Afferent Innervation, Muscle Spindles, and Contractures Following Neonatal Brachial Plexus Injury in a Mouse Model.

    Science.gov (United States)

    Nikolaou, Sia; Hu, Liangjun; Cornwall, Roger

    2015-10-01

    We used an established mouse model of elbow flexion contracture after neonatal brachial plexus injury (NBPI) to test the hypothesis that preservation of afferent innervation protects against contractures and is associated with preservation of muscle spindles and ErbB signaling. A model of preganglionic C5 through C7 NBPI was first tested in mice with fluorescent axons using confocal imaging to confirm preserved afferent innervation of spindles despite motor end plate denervation. Preganglionic and postganglionic injuries were then created in wild-type mice. Four weeks later, we assessed total and afferent denervation of the elbow flexors by musculocutaneous nerve immunohistochemistry. Biceps muscle volume and cross-sectional area were measured by micro computed tomography. An observer who was blinded to the study protocol measured elbow flexion contractures. Biceps spindle and muscle fiber morphology and ErbB signaling pathway activity were assessed histologically and immunohistochemically. Preganglionic and postganglionic injuries caused similar total denervation and biceps muscle atrophy. However, after preganglionic injuries, afferent innervation was partially preserved and elbow flexion contractures were significantly less severe. Spindles degenerated after postganglionic injury but were preserved after preganglionic injury. ErbB signaling was inactivated in denervated spindles after postganglionic injury but ErbB signaling activity was preserved in spindles after preganglionic injury with retained afferent innervation. Preganglionic and postganglionic injuries were associated with upregulation of ErbB signaling in extrafusal muscle fibers. Contractures after NBPI are associated with muscle spindle degeneration and loss of spindle ErbB signaling activity. Preservation of afferent innervation maintained spindle development and ErbB signaling activity, and protected against contractures. Pharmacologic modulation of ErbB signaling, which is being investigated as a

  6. Sex differences in primary muscle afferent sensitization following ischemia and reperfusion injury.

    Science.gov (United States)

    Ross, Jessica L; Queme, Luis F; Lamb, Jordan E; Green, Kathryn J; Jankowski, Michael P

    2018-01-03

    Chronic pain conditions are more prevalent in women, but most preclinical studies into mechanisms of pain generation are performed using male animals. Furthermore, whereas group III and IV nociceptive muscle afferents provoke central sensitization more effectively than their cutaneous counterparts, less is known about this critical population of muscle nociceptors. Here, we compare the physiology of individual muscle afferents in uninjured males and females. We then characterize the molecular, physiological, and behavioral effects of transient ischemia and reperfusion injury (I/R), a model we have extensively studied in males and in females. Response properties and phenotypes to mechanical, thermal, and chemical stimulation were compared using an ex vivo muscle/nerve/dorsal root ganglia (DRG)/spinal cord recording preparation. Analyses of injury-related changes were also performed by assaying evoked and spontaneous pain-related behaviors, as well as mRNA expression of the affected muscle and DRGs. The appropriate analyses of variance and post hoc tests (with false discovery rate corrections when needed) were performed for each measure. Females have more mechanically sensitive muscle afferents and show greater mechanical and thermal responsiveness than what is found in males. With I/R, both sexes show fewer cells responsive to an innocuous metabolite solution (ATP, lactic acid, and protons), and lower mechanical thresholds in individual afferents; however, females also possess altered thermal responsiveness, which may be related to sex-dependent changes in gene expression within the affected DRGs. Regardless, both sexes show similar increases in I/R-induced pain-like behaviors. Here, we illustrate a unique phenomenon wherein discrete, sex-dependent mechanisms of primary muscle afferent sensitization after ischemic injury to the periphery may underlie similar behavioral changes between the sexes. Furthermore, although the group III and IV muscle afferents are fully

  7. Afferent baroreflex failure in familial dysautonomia

    Science.gov (United States)

    Norcliffe-Kaufmann, Lucy; Axelrod, Felicia; Kaufmann, Horacio

    2010-01-01

    Background: Familial dysautonomia (FD) is due to a genetic deficiency of the protein IKAP, which affects development of peripheral neurons. Patients with FD display complex abnormalities of the baroreflex of unknown cause. Methods: To test the hypothesis that the autonomic phenotype of FD is due to selective impairment of afferent baroreceptor input, we examined the autonomic and neuroendocrine responses triggered by stimuli that either engage (postural changes) or bypass (cognitive/emotional) afferent baroreflex pathways in 50 patients with FD and compared them to those of normal subjects and to those of patients with pure autonomic failure (PAF), a disorder with selective impairment of efferent autonomic neurons. Results: During upright tilt, in patients with FD and in patients with PAF blood pressure fell markedly but the heart rate increased in PAF and decreased in FD. Plasma norepinephrine levels failed to increase in both groups. Vasopressin levels increased appropriately in patients with PAF but failed to increase in patients with FD. Head-down tilt increased blood pressure in both groups but increased heart rate only in patients with FD. Mental stress evoked a marked increase in blood pressure and heart rate in patients with FD but little change in those with PAF. Conclusion: The failure to modulate sympathetic activity and to release vasopressin by baroreflex-mediated stimuli together with marked sympathetic activation during cognitive tasks indicate selective failure of baroreceptor afference. These findings indicate that IKAP is critical for the development of afferent baroreflex pathways and has therapeutic implications in the management of these patients. GLOSSARY FD = familial dysautonomia; FVR = forearm vascular resistance; PAF = pure autonomic failure. PMID:21098405

  8. Evaluating developmental motor plasticity with paired afferent stimulation.

    Science.gov (United States)

    Damji, Omar; Keess, Jamie; Kirton, Adam

    2015-06-01

    Brain plasticity mechanisms are probably different in children but remain poorly understood. Paired afferent stimulation (PAS) combines peripheral sensory stimulation with transcranial magnetic stimulation (TMS) of primary motor cortex to induce rapid, reversible, topographically specific increases in primary motor cortex excitability suggestive of long-term potentiation in adults. Our aim was to determine frequency, characteristics, age effects, and reproducibility of PAS in school-age children. Typically developing right-handed children (6-18y) were recruited. Median nerve stimulation was delivered 25ms before suprathreshold primary motor cortex stimulation (0.2Hz, 7.5min). Primary outcome was changed in the amplitude of motor evoked potentials (MEPs) at five time points after PAS (0, 15, 30, 45, 75min) expressed as area under the curve. Reproducibility was evaluated. Secondary outcomes included stimulus response curves and safety/tolerability. Of 28 children (20 males, mean age 12y), 64% demonstrated PAS effects (11 definite, seven probable). PAS effects were sustained across all time points to 75min (p=0.004). Stimulus response curve scores increased after PAS (n=9, p=0.02). PAS effect and age were not correlated. PAS was highly reproducible (p=0.925, r=0.283). Tolerability was favorable without adverse events. PAS effects are present and reproducible in children. Pediatric PAS paradigms appear safe and tolerable. PAS may provide insight into endogenous developmental plasticity, informing future studies in children with cerebral palsy and other motor disorders. © 2015 Mac Keith Press.

  9. Models of utricular bouton afferents: role of afferent-hair cell connectivity in determining spike train regularity.

    Science.gov (United States)

    Holmes, William R; Huwe, Janice A; Williams, Barbara; Rowe, Michael H; Peterson, Ellengene H

    2017-05-01

    Vestibular bouton afferent terminals in turtle utricle can be categorized into four types depending on their location and terminal arbor structure: lateral extrastriolar (LES), striolar, juxtastriolar, and medial extrastriolar (MES). The terminal arbors of these afferents differ in surface area, total length, collecting area, number of boutons, number of bouton contacts per hair cell, and axon diameter (Huwe JA, Logan CJ, Williams B, Rowe MH, Peterson EH. J Neurophysiol 113: 2420-2433, 2015). To understand how differences in terminal morphology and the resulting hair cell inputs might affect afferent response properties, we modeled representative afferents from each region, using reconstructed bouton afferents. Collecting area and hair cell density were used to estimate hair cell-to-afferent convergence. Nonmorphological features were held constant to isolate effects of afferent structure and connectivity. The models suggest that all four bouton afferent types are electrotonically compact and that excitatory postsynaptic potentials are two to four times larger in MES afferents than in other afferents, making MES afferents more responsive to low input levels. The models also predict that MES and LES terminal structures permit higher spontaneous firing rates than those in striola and juxtastriola. We found that differences in spike train regularity are not a consequence of differences in peripheral terminal structure, per se, but that a higher proportion of multiple contacts between afferents and individual hair cells increases afferent firing irregularity. The prediction that afferents having primarily one bouton contact per hair cell will fire more regularly than afferents making multiple bouton contacts per hair cell has implications for spike train regularity in dimorphic and calyx afferents. NEW & NOTEWORTHY Bouton afferents in different regions of turtle utricle have very different morphologies and afferent-hair cell connectivities. Highly detailed

  10. Effects of afferent input on the breathing pattern continuum in the tambaqui (Colossoma macropomum).

    Science.gov (United States)

    Reid, Stephen G; Sundin, Lena; Florindo, Luis Henrique; Rantin, Francisco Tadeu; Milsom, William K

    2003-06-12

    This study used a decerebrate and artificially-ventilated preparation to examine the roles of various afferent inputs in breathing pattern formation in the tambaqui (Colossoma macropomum). Three general breathing patterns were observed: (1) regular breathing; (2) frequency cycling and (3) episodic breathing. Under normoxic, normocapnic conditions, 50% of control fish exhibited regular continuous breathing and 50% exhibited frequency cycling. Denervation of the gills and oro-branchial cavity promoted frequency cycling. Central denervation of the glossopharyngeal and vagus nerves produced episodic breathing. Regardless of the denervation state, hyperoxia produced either frequency cycling or episodic breathing while hypoxia and hypercarbia shifted the pattern to frequency cycling and continuous breathing. We suggest that these breathing patterns represent a continuum from continuous to episodic breathing with waxing and waning occupying an intermediate stage. The data further suggest that breathing pattern is influenced by both specific afferent input from chemoreceptors and generalised afferent input while chemoreceptors specific for producing changes in breathing pattern may exist in fish.

  11. Evaluation of dermal myelinated nerve fibers in diabetes mellitus

    Science.gov (United States)

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

    2013-01-01

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

  12. Airway Clearance Techniques (ACTs)

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    Full Text Available ... Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home Life With CF Treatments and Therapies Airway Clearance Airway Clearance Techniques (ACTs) There are different ways to clear your airways. Most are easy to ...

  13. Airway Clearance Techniques (ACTs)

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    Full Text Available ... Treatments and Therapies Airway Clearance Airway Clearance Techniques (ACTs) There are different ways to clear your airways. ... or caregiver. Older kids and adults can choose ACTs that they can do on their own. Share ...

  14. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... CF Treatments and Therapies Airway Clearance Airway Clearance Techniques (ACTs) There are different ways to clear your ... for fitting ACTs into daily life Airway Clearance Techniques | Webcast To learn more about how you can ...

  15. Chloride regulates afferent arteriolar contraction in response to depolarization

    DEFF Research Database (Denmark)

    Hansen, P B; Jensen, B L; Skott, O

    1998-01-01

    -Renal vascular reactivity is influenced by the level of dietary salt intake. Recent in vitro data suggest that afferent arteriolar contractility is modulated by extracellular chloride. In the present study, we assessed the influence of chloride on K+-induced contraction in isolated perfused rabbit...... and for the sympathetic nervous system in renal afferent arterioles. This could be of physiological relevance for the resetting of afferent arteriolar sensitivity during changes in salt intake....

  16. Cholecystokinin enhances visceral pain-related affective memory via vagal afferent pathway in rats

    Directory of Open Access Journals (Sweden)

    Cao Bing

    2012-06-01

    Full Text Available Abstract Background Pain contains both sensory and affective dimensions. Using a rodent visceral pain assay that combines the colorectal distension (CRD model with the conditioned place avoidance (CPA paradigms, we measured a learned behavior that directly reflects the affective component of visceral pain, and showed that perigenual anterior cingulate cortex (pACC activation is critical for memory processing involved in long-term visceral affective state and prediction of aversive stimuli by contextual cue. Progress has been made and suggested that activation of vagal afferents plays a role in the behavioral control nociception and memory storage processes. In human patients, electrical vagus nerve stimulation enhanced retention of verbal learning performance. Cholecystokinin-octapeptide (CCK, which is a gastrointestinal hormone released during feeding, has been shown to enhance memory retention. Mice access to food immediately after training session enhanced memory retention. It has been well demonstrated that CCK acting on vagal afferent fibers mediates various physiological functions. We hypothesize that CCK activation of vagal afferent enhances visceral pain-related affective memory. Results In the presented study, infusion of CCK-8 at physiological concentration combining with conditional training significantly increased the CRD-induced CPA scores, and enhanced the pain affective memory retention. In contrast, CCK had no effect on CPA induced by non-nociceptive aversive stimulus (U69,593. The physiological implications were further strengthened by the similar effects observed in the rats with duodenal infusion of 5% peptone, which has been shown to induce increases in plasma CCK levels. CCK-8 receptor antagonist CR-1409 or perivagal application of capsaicin abolished the effect of CCK on aversive visceral pain memory, which was consistent with the notion that vagal afferent modulates affective aspects of visceral pain. CCK does not change

  17. Differential dynamic processing of afferent signals in frog tonic and phasic second-order vestibular neurons.

    Science.gov (United States)

    Pfanzelt, Sandra; Rössert, Christian; Rohregger, Martin; Glasauer, Stefan; Moore, Lee E; Straka, Hans

    2008-10-08

    The sensory-motor transformation of the large dynamic spectrum of head-motion-related signals occurs in separate vestibulo-ocular pathways. Synaptic responses of tonic and phasic second-order vestibular neurons were recorded in isolated frog brains after stimulation of individual labyrinthine nerve branches with trains of single electrical pulses. The timing of the single pulses was adapted from spike discharge patterns of frog semicircular canal nerve afferents during sinusoidal head rotation. Because each electrical pulse evoked a single spike in afferent fibers, the resulting sequences with sinusoidally modulated intervals and peak frequencies up to 100 Hz allowed studying the processing of presynaptic afferent inputs with in vivo characteristics in second-order vestibular neurons recorded in vitro in an isolated whole brain. Variation of pulse-train parameters showed that the postsynaptic compound response dynamics differ in the two types of frog vestibular neurons. In tonic neurons, subthreshold compound responses and evoked discharge patterns exhibited relatively linear dynamics and were generally aligned with pulse frequency modulation. In contrast, compound responses of phasic neurons were asymmetric with large leads of subthreshold response peaks and evoked spike discharge relative to stimulus waveform. These nonlinearities were caused by the particular intrinsic properties of phasic vestibular neurons and were facilitated by GABAergic and glycinergic inhibitory inputs from tonic type vestibular interneurons and by cerebellar circuits. Coadapted intrinsic filter and emerging network properties thus form dynamically different neuronal elements that provide the appropriate cellular basis for a parallel processing of linear, tonic, and nonlinear phasic vestibulo-ocular response components in central vestibular neurons.

  18. Limb venous distension evokes sympathetic activation via stimulation of the limb afferents in humans

    Science.gov (United States)

    Cui, Jian; McQuillan, Patrick M.; Blaha, Cheryl; Kunselman, Allen R.

    2012-01-01

    We have recently shown that a saline infusion in the veins of an arterially occluded human forearm evokes a systemic response with increases in muscle sympathetic nerve activity (MSNA) and blood pressure. In this report, we examined whether this response was a reflex that was due to venous distension. Blood pressure (Finometer), heart rate, and MSNA (microneurography) were assessed in 14 young healthy subjects. In the saline trial (n = 14), 5% forearm volume normal saline was infused in an arterially occluded arm. To block afferents in the limb, 90 mg of lidocaine were added to the same volume of saline in six subjects during a separate visit. To examine whether interstitial perfusion of normal saline alone induced the responses, the same volume of albumin solution (5% concentration) was infused in 11 subjects in separate studies. Lidocaine abolished the MSNA and blood pressure responses seen with saline infusion. Moreover, compared with the saline infusion, an albumin infusion induced a larger (MSNA: Δ14.3 ± 2.7 vs. Δ8.5 ± 1.3 bursts/min, P blood pressure responses. These data suggest that venous distension activates afferent nerves and evokes a powerful systemic sympathoexcitatory reflex. We posit that the venous distension plays an important role in evoking the autonomic adjustments seen with postural stress in human subjects. PMID:22707559

  19. [Bilateral mandibular nerve injury following mask ventilation: a case report].

    Science.gov (United States)

    Tuncali, Bahattin; Zeyneloglu, Pinar

    2018-03-19

    Nerve injury following mask ventilation is a rare but serious anesthetic complication. The majority of reported cases are associated with excessive pressure applied to the face mask, long duration of mask ventilation, excessive digital pressure behind the mandible to relieve airway obstruction and pressure exerted by the plastic oropharyngeal airway. We present a case of bilateral mandibular nerve injury following mask ventilation with short duration, most likely due to a semi-silicone facemask with an over-inflated cushion. An over-inflated sealing cushion of a facemask may trigger difficult mask ventilation leading to mandibular nerve injury following mask ventilation. Alternative airway management techniques such as laryngeal mask airway should be considered when airway maintenance can only be achieved with strong pressure applied to the facemask and/or mandible. Copyright © 2018. Publicado por Elsevier Editora Ltda.

  20. Airway distensibility in Chronic Obstructive Airway Disease

    DEFF Research Database (Denmark)

    Winkler Wille, Mathilde Marie; Pedersen, Jesper Holst; Dirksen, Asger

    2013-01-01

    Rationale – Chronic Obstructive Pulmonary Disease (COPD) is a combination of chronic bronchitis and emphysema, which both may lead to airway obstruction. Under normal circumstances, airway dimensions vary as a function of inspiration level. We aim to study the influence of COPD and emphysema on t...... in causing airway narrowing, the latter most likely due to loss of elastic recoil of surrounding tissue....

  1. SLOWLY ADAPTING SENSORY UNITS HAVE MORE RECEPTORS IN LARGE AIRWAYS THAN IN SMALL AIRWAYS IN RABBITS

    Directory of Open Access Journals (Sweden)

    Jun Liu

    2016-12-01

    Full Text Available Sensory units of pulmonary slowly adapting receptors (SARs are more active in large airways than in small airways. However, there is no explanation for this phenomenon. Although sensory structures in large airways resemble those in small airways, they are bigger and more complex. Possibly, a larger receptor provides greater surface area for depolarization, and thus has a lower activating threshold and/or a higher sensitivity to stretch, leading to more nerve electrical activities. Recently, a single sensory unit has been reported to contain multiple receptors. Therefore, sensory units in large airways may contain more SARs, which may contribute to high activities. To test this hypothesis, we used a double staining technique to identify sensory receptor sizes. We labeled the sensory structure with Na+/K+-ATPase antibodies and the myelin sheath with myelin basic protein (MBP antibodies. A SAR can be defined as the end formation beyond MBP labeling. Thus, we are able to compare sizes of sensory structures and SARs in large (trachea and bronchi vs small (bronchioles 0.05. However, the sensory structure contains more SARs in large airways than in small airways (9.6±0.6 vs 3.6±0.3; P<0.0001. Thus, our data support the hypothesis that greater numbers of SARs in sensory units of large airways may contribute to higher activities.

  2. Nerve fiber bundle visual field defect resulting from a giant peripapillary cotton-wool spot.

    Science.gov (United States)

    Chaum, E; Drewry, R D; Ware, G T; Charles, S

    2001-12-01

    Cotton-wool spots are the clinical manifestation of focal infarcts of the retinal nerve fiber layer. They rarely cause significant visual field loss. A large idiopathic cotton-wool spot in a 34-year-old healthy woman caused a nerve fiber bundle visual field defect and an afferent pupillary defect that remained after the cotton-wool spot had disappeared and the retina and optic nerve appeared normal.

  3. Transcutaneous Vagus Nerve Stimulation: A Promising Method for Treatment of Autism Spectrum Disorders

    OpenAIRE

    Jin, Yu; Kong, Jian

    2017-01-01

    Transcutaneous Vagus Nerve Stimulation (tVNS) on the auricular branch of the vagus nerve has been receiving attention due to its therapeutic potential for neuropsychiatric disorders. Although the mechanism of tVNS is not yet completely understood, studies have demonstrated the potential role of vagal afferent nerve stimulation in the regulation of mood and visceral state associated with social communication. In addition, a growing body of evidence shows that tVNS can activate the brain region...

  4. Muscle afferent receptors engaged in augmented sympathetic responsiveness in peripheral artery disease

    Directory of Open Access Journals (Sweden)

    Jianhua eLi

    2012-07-01

    Full Text Available The exercise pressor reflex (EPR is a neural control mechanism responsible for the cardiovascular responses to exercise. As exercise is initiated, thin fiber muscle afferent nerves are activated by mechanical and metabolic stimuli arising in the contracting muscles. This leads to reflex increases in arterial blood pressure and heart rate primarily through activation of sympathetic nerve activity (SNA. Studies of humans and animals have indicated that the EPR is exaggerated in a number of cardiovascular diseases. For the last several years, studies have specifically employed a rodent model to examine the mechanisms at receptor and cellular levels by which responses of SNA and blood pressure to static exercise are heightened in peripheral artery disease (PAD, one of the most common cardiovascular disorders. A rat model of this disease has well been established. Specifically, femoral artery occlusion is used to study intermittent claudication that is observed in human PAD. The receptors on thin fiber muscle afferents that are engaged in this disease include transient receptor potential vanilloid type 1 (TRPV1, purinergic P2X and acid sensing ion channel (ASIC. The role played by nerve growth factor (NGF in regulating those sensory receptors in the processing of amplified EPR was also investigated. The purpose of this review is to focus on a theme namely that PAD accentuates autonomic reflex responses to exercise and further address regulatory mechanisms leading to abnormal sympathetic responsiveness. This review will present some of recent results in regard with several receptors in muscle sensory neurons in contribution to augmented autonomic reflex responses in PAD. Review of the findings from recent studies would lead to a better understanding in integrated processing of sympathetic nervous system in PAD.

  5. Nerve conduction

    Science.gov (United States)

    ... the central nervous system (CNS) and peripheral nervous system (PNS). The CNS contains the brain and the spinal cord and the PNS consists of thousands of nerves that connect the spinal cord to muscles and sensory receptors. A peripheral nerve is composed of nerve ...

  6. Convergence of cranial visceral afferents within the solitary tract nucleus.

    Science.gov (United States)

    McDougall, Stuart J; Peters, James H; Andresen, Michael C

    2009-10-14

    Primary afferent axons within the solitary tract (ST) relay homeostatic information via glutamatergic synapses directly to second-order neurons within the nucleus of the solitary tract (NTS). These primary afferents arise from multiple organ systems and relay multiple sensory modalities. How this compact network organizes the flow of primary afferent information will shape central homeostatic control. To assess afferent convergence and divergence, we recorded ST-evoked synaptic responses in pairs of medial NTS neurons in horizontal brainstem slices. ST shocks activated EPSCs along monosynaptic or polysynaptic pathways. Gradations in shock intensity discriminated multiple inputs and stimulus recruitment profiles indicated that each EPSC was unitary. In 24 pairs, 75% were second-order neurons with 64% receiving one direct ST input with the remainder receiving additional convergent ST afferent inputs (22% two; 14% three monosynaptic ST-EPSCs). Some (34%) second-order neurons received polysynaptic EPSCs. Neurons receiving only higher-order inputs were uncommon (13%). Most ST-EPSCs were completely independent, but 4 EPSCs of a total of 81 had equal thresholds, highly correlated latencies, and synchronized synaptic failures consistent with divergence from a single source ST axon or from a common interneuron producing a pair of polysynaptic EPSCs. We conclude that ST afferent inputs are remarkably independent with little evidence of substantial shared information. Individual cells receive highly focused information from the viscera. Thus, afferent excitation of second-order NTS neurons is generally dominated by single visceral afferents and therefore focused on a single afferent modality and/or organ region.

  7. Arginase strongly impairs neuronal nitric oxide-mediated airway smooth muscle relaxation in allergic asthma

    NARCIS (Netherlands)

    Maarsingh, H; Leusink, J; Bos, IST; Zaagsma, J; Meurs, H

    2006-01-01

    Background: Using guinea pig tracheal preparations, we have recently shown that endogenous arginase activity attenuates inhibitory nonadrenergic noncholinergic (iNANC) nerve-mediated airway smooth muscle relaxation by reducing nitric oxide (NO) production - due to competition with neuronal

  8. The pattern of excitation of human lower limb motoneurones by probable group II muscle afferents.

    Science.gov (United States)

    Simonetta-Moreau, M; Marque, P; Marchand-Pauvert, V; Pierrot-Deseilligny, E

    1999-05-15

    1. Heteronymous group II effects were investigated in the human lower limb. Changes in firing probability of single motor units in quadriceps (Q), biceps (Bi), semitendinosus (ST), gastrocnemius medialis (GM) and tibialis anterior (TA) were studied after electrical stimuli between 1 and 3 times motor threshold (MT) applied to common peroneal (CP), superficial (SP) and deep (DP) peroneal, Bi and GM nerves in those nerve-muscle combinations without recurrent inhibition. 2. Stimulation of the CP and Bi nerves evoked in almost all of the explored Q motor units a biphasic excitation with a low-threshold early peak, attributable to non-monosynaptic group I excitation, and a higher threshold late peak. When the CP nerve was cooled (or the stimulation applied to a distal branch, DP), the increase in latency was greater for the late than for the early peak, indicating that the late excitation is due to stimulation of afferents with a slower conduction velocity than group I fibres, presumably in the group II range. In ST motor units the group II excitation elicited by stimulation of the GM and SP nerves was particularly large and frequent, and the non-monosynaptic group I excitation was often replaced by an inhibition. 3. A late group II-induced excitation from CP to Q motoneurones and from GM and SP to ST motoneurones was also observed when using the H reflex as a test. 4. The electrical threshold and conduction velocity of the largest diameter fibres evoking the group II excitation were estimated to be 2.1 and 0.65 times those of the fastest Ia afferents, respectively. In the combinations tested in the present investigation the group II input seemed to be primarily of muscle origin. 5. The potent heteronymous group II excitation of motoneurones of both flexors and extensors of the knee contrasted with the absence of a group II effect from DP to GM and from GM to TA. In none of the combinations explored was there any evidence for group II inhibition of motoneurones. The

  9. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... of treatment options. Airway Clearance Active Cycle of Breathing Technique Airway Clearance Techniques Autogenic Drainage Basics of ... Pulmonary Exacerbations Clinical Care Guidelines SCREENING & TREATING DEPRESSION & ANXIETY GUIDELINES Clinician Resources As a clinician, you’re ...

  10. Histamine upregulates Nav1.8 expression in primary afferent neurons via H2 receptors: involvement in neuropathic pain.

    Science.gov (United States)

    Yue, Jia-Xing; Wang, Ran-Ran; Yu, Jie; Tang, Ying-Ying; Hou, Wei-Wei; Lou, Guo-Dong; Zhang, Shi-Hong; Chen, Zhong

    2014-10-01

    The upregulation of Nav1.8 in primary afferents plays a critical role in the development and persistence of neuropathic pain. The mechanisms underlying the upregulation are not fully understood. The present study aims to investigate the regulatory effect of histamine on the expression of Nav1.8 in primary afferent neurons and its involvement in neuropathic pain. Histamine at 10(-8) M increased the expression of Nav1.8 in cultured DRG neurons. This effect could be blocked by H2 receptor antagonist cimetidine or famotidine, but not by H1 receptor antagonist pyrilamine or dual H3 /H4 antagonist thioperamide. Peri-sciatic administration of histamine increased Nav1.8 expression in the sciatic nerve and L4/L5 DRG neurons in a dose-dependent manner, accompanied with remarkable mechanical allodynia and heat hyperalgesia in the ipsilateral hindpaw. Famotidine but not pyrilamine or thioperamide inhibited Nav1.8 upregulation and pain hypersensitivity. In addition, famotidine (40 mg/kg, i.p.) not only suppressed autotomy behavior in the rat neuroma model of neuropathic pain but also attenuated mechanical allodynia and thermal hyperalgesia following partial sciatic nerve ligation. Moreover, famotidine inhibited Nav1.8 upregulation in the neuroma and ligated sciatic nerve. Our findings indicate that histamine increases Nav1.8 expression in primary afferent neurons via H2 receptor-mediated pathway and thereby contributes to neuropathic pain. H2 receptor antagonists may potentially be used as analgesics for patients with neuropathic pain. © 2014 John Wiley & Sons Ltd.

  11. Terminal nerve: cranial nerve zero

    Directory of Open Access Journals (Sweden)

    Jorge Eduardo Duque Parra

    2006-12-01

    Full Text Available It has been stated, in different types of texts, that there are only twelve pairs of cranial nerves. Such texts exclude the existence of another cranial pair, the terminal nerve or even cranial zero. This paper considers the mentioned nerve like a cranial pair, specifying both its connections and its functional role in the migration of liberating neurons of the gonadotropic hormone (Gn RH. In this paper is also stated the hypothesis of the phylogenetic existence of a cerebral sector and a common nerve that integrates the terminal nerve with the olfactory nerves and the vomeronasals nerves which seem to carry out the odors detection function as well as in the food search, pheromone detection and nasal vascular regulation.

  12. Tyrosine Hydroxylase Expression in Type II Cochlear Afferents in Mice.

    Science.gov (United States)

    Vyas, Pankhuri; Wu, Jingjing Sherry; Zimmerman, Amanda; Fuchs, Paul; Glowatzki, Elisabeth

    2017-02-01

    Acoustic information propagates from the ear to the brain via spiral ganglion neurons that innervate hair cells in the cochlea. These afferents include unmyelinated type II fibers that constitute 5 % of the total, the majority being myelinated type I neurons. Lack of specific genetic markers of type II afferents in the cochlea has been a roadblock in studying their functional role. Unexpectedly, type II afferents were visualized by reporter proteins induced by tyrosine hydroxylase (TH)-driven Cre recombinase. The present study was designed to determine whether TH-driven Cre recombinase (TH-2A-CreER) provides a selective and reliable tool for identification and genetic manipulation of type II rather than type I cochlear afferents. The "TH-2A-CreER neurons" radiated from the spiral lamina, crossed the tunnel of Corti, turned towards the base of the cochlea, and traveled beneath the rows of outer hair cells. Neither the processes nor the somata of TH-2A-CreER neurons were labeled by antibodies that specifically labeled type I afferents and medial efferents. TH-2A-CreER-positive processes partially co-labeled with antibodies to peripherin, a known marker of type II afferents. Individual TH-2A-CreER neurons gave off short branches contacting 7-25 outer hair cells (OHCs). Only a fraction of TH-2A-CreER boutons were associated with CtBP2-immunopositive ribbons. These results show that TH-2A-CreER provides a selective marker for type II versus type I afferents and can be used to describe the morphology and arborization pattern of type II cochlear afferents in the mouse cochlea.

  13. [Acute pancreatitis and afferent loop syndrome. Case report].

    Science.gov (United States)

    Barajas-Fregoso, Elpidio Manuel; Romero-Hernández, Teodoro; Macías-Amezcua, Michel Dassaejv

    2013-01-01

    The afferent syndrome loop is a mechanic obstruction of the afferent limb before a Billroth II or Roux-Y reconstruction, secondary in most of case to distal or subtotal gastrectomy. Clinical case: Male 76 years old, with antecedent of cholecystectomy, gastric adenocarcinoma six years ago, with subtotal gastrectomy and Roux-Y reconstruction. Beginning a several abdominal pain, nausea and vomiting, abdominal distension, without peritoneal irritation sings. Amylase 1246 U/L, lipase 3381 U/L. Computed Tomography with thickness wall and dilatation of afferent loop, pancreas with diffuse enlargement diagnostic of acute pancreatitis secondary an afferent loop syndrome. The afferent loop syndrome is presented in 0.3%-1% in all cases with Billroth II reconstruction, with a mortality of up to 57%, the obstruction lead accumulation of bile, pancreatic and intestinal secretions, increasing the pressure and resulting in afferent limb, bile conduct and Wirsung conduct dilatation, triggering an inflammatory response that culminates in pancreatic inflammation. The severity of the presentation is related to the degree and duration of the blockage.

  14. Afferent loop syndrome: Role of sonography and CT

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Ho; Lim, Jae Hoon; Ko, Young Tae [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1992-03-15

    Afferent loop syndrome(ALS) is caused by obstruction of the afferent loop after subtotal gastrectomy with Billroth II gastrojejunostomy. Prompt diagnosis of ALS is important as perforation of the loop occurs. The aim of study is to ascertain the sonography and CT to diagnose ALS. We describe the radiologic findings in ten patients with ALS. The cause of ALS, established at surgery, included cancer recurrence (n=4), internal hernia (n=4), marginal ulcer (n=1), and development of cancer at the anastomosis site (n=1). Abdominal X-ray and sonography were performed in all cases, upper GI series in five cases and computed tomography in two cases. The dilated afferent loop was detected in only two cases out often patients in retrospective review of abdominal X-ray. ALS with recurrence of cancer was diagnosed in three cases by upper GI series. Of the cases that had sonography, the afferent loop was seen in the upper abdomen crossing transversely over the midline in all ten patients. The cause of ALS were predicated on the basis of the sonograms in three of the five patients. In two cases of computed tomography, the dilated afferent loop and recurrent cancer at the remnant stomach were seen.Our experience suggests that the diagnosis of afferent syndrome can be made on the basis of the typical anatomic location and shape of the dilated bowel loop in both sonography and computed tomography.

  15. Afferent innervation of the utricular macula in pigeons

    Science.gov (United States)

    Si, Xiaohong; Zakir, Mridha Md; Dickman, J. David

    2003-01-01

    Biotinylated dextran amine (BDA) was used to retrogradely label afferents innervating the utricular macula in adult pigeons. The pigeon utriclar macula consists of a large rectangular-shaped neuroepithelium with a dorsally curved anterior edge and an extended medioposterior tail. The macula could be demarcated into several regions based on cytoarchitectural differences. The striola occupied 30% of the macula and contained a large density of type I hair cells with fewer type II hair cells. Medial and lateral extrastriola zones were located outside the striola and contained only type II hair cells. A six- to eight-cell-wide band of type II hair cells existed near the center of the striola. The reversal line marked by the morphological polarization of hair cells coursed throughout the epithelium, near the peripheral margin, and through the center of the type II band. Calyx afferents innervated type I hair cells with calyceal terminals that contained between 2 and 15 receptor cells. Calyx afferents were located only in the striola region, exclusive of the type II band, had small total fiber innervation areas and low innervation densities. Dimorph afferents innervated both type I and type II hair cells with calyceal and bouton terminals and were primarily located in the striola region. Dimorph afferents had smaller calyceal terminals with few type I hair cells, extended fiber branches with bouton terminals and larger innervation areas. Bouton afferents innervated only type II hair cells in the extrastriola and type II band regions. Bouton afferents innervating the type II band had smaller terminal fields with fewer bouton terminals and smaller innervation areas than fibers located in the extrastriolar zones. Bouton afferents had the most bouton terminals on the longest fibers, the largest innervation areas with the highest innervation densities of all afferents. Among all afferents, smaller terminal innervation fields were observed in the striola and large fields were

  16. Primary afferent and spinal cord expression of gastrin-releasing peptide: message, protein, and antibody concerns.

    Science.gov (United States)

    Solorzano, Carlos; Villafuerte, David; Meda, Karuna; Cevikbas, Ferda; Bráz, Joao; Sharif-Naeini, Reza; Juarez-Salinas, Dina; Llewellyn-Smith, Ida J; Guan, Zhonghui; Basbaum, Allan I

    2015-01-14

    There is continuing controversy relating to the primary afferent neurotransmitter that conveys itch signals to the spinal cord. Here, we investigated the DRG and spinal cord expression of the putative primary afferent-derived "itch" neurotransmitter, gastrin-releasing peptide (GRP). Using ISH, qPCR, and immunohistochemistry, we conclude that GRP is expressed abundantly in spinal cord, but not in DRG neurons. Titration of the most commonly used GRP antiserum in tissues from wild-type and GRP mutant mice indicates that the antiserum is only selective for GRP at high dilutions. Paralleling these observations, we found that a GRPeGFP transgenic reporter mouse has abundant expression in superficial dorsal horn neurons, but not in the DRG. In contrast to previous studies, neither dorsal rhizotomy nor an intrathecal injection of capsaicin, which completely eliminated spinal cord TRPV1-immunoreactive terminals, altered dorsal horn GRP immunoreactivity. Unexpectedly, however, peripheral nerve injury induced significant GRP expression in a heterogeneous population of DRG neurons. Finally, dual labeling and retrograde tracing studies showed that GRP-expressing neurons of the superficial dorsal horn are predominantly interneurons, that a small number coexpress protein kinase C gamma (PKCγ), but that none coexpress the GRP receptor (GRPR). Our studies support the view that pruritogens engage spinal cord "itch" circuits via excitatory superficial dorsal horn interneurons that express GRP and that likely target GRPR-expressing interneurons. The fact that peripheral nerve injury induced de novo GRP expression in DRG neurons points to a novel contribution of this peptide to pruritoceptive processing in neuropathic itch conditions. Copyright © 2015 Solorzano et al.

  17. Theobromine inhibits sensory nerve activation and cough.

    Science.gov (United States)

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

    2005-02-01

    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, in a randomized, double-blind, placebo-controlled study in man, theobromine suppresses capsaicin-induced cough with no adverse effects. We also demonstrate that theobromine directly inhibits capsaicin-induced sensory nerve depolarization of guinea-pig and human vagus nerve suggestive of an inhibitory effect on afferent nerve activation. These data indicate the actions of theobromine appear to be peripherally mediated. We conclude theobromine is a novel and promising treatment, which may form the basis for a new class of antitussive drugs.

  18. Myelinated Afferents Are Involved in Pathology of the Spontaneous Electrical Activity and Mechanical Hyperalgesia of Myofascial Trigger Spots in Rats.

    Science.gov (United States)

    Meng, Fei; Ge, Hong-You; Wang, Yong-Hui; Yue, Shou-Wei

    2015-01-01

    Myofascial trigger points (MTrPs) are common causes for chronic pain. Myelinated afferents were considered to be related with muscular pain, and our clinical researches indicated they might participate in the pathology of MTrPs. Here, we applied myofascial trigger spots (MTrSs, equal to MTrPs in human) of rats to further investigate role of myelinated afferents. Modified pyridine-silver staining revealed more nerve endings at MTrSs than non-MTrSs (P MPTs) of MTrSs were lower than those of non-MTrSs (P MPTs of MTrSs significantly (P MPTs of non-MTrSs first decreased (P 0.05). 30 min after the injection, MPTs at MTrSs were significantly lower than those of non-MTrSs (P < 0.01). Therefore, we concluded that proliferated myelinated afferents existed at MTrSs, which were closely related to pathology of SEA and mechanical hyperalgesia of MTrSs.

  19. Terminal nerve: cranial nerve zero

    OpenAIRE

    Jorge Eduardo Duque Parra; Carlos Alberto Duque Parra

    2006-01-01

    It has been stated, in different types of texts, that there are only twelve pairs of cranial nerves. Such texts exclude the existence of another cranial pair, the terminal nerve or even cranial zero. This paper considers the mentioned nerve like a cranial pair, specifying both its connections and its functional role in the migration of liberating neurons of the gonadotropic hormone (Gn RH). In this paper is also stated the hypothesis of the phylogenetic existence of a cerebral sector and a co...

  20. Chronic recruitment of primary afferent neurons by microstimulation in the feline dorsal root ganglia

    Science.gov (United States)

    Fisher, Lee E.; Ayers, Christopher A.; Ciollaro, Mattia; Ventura, Valérie; Weber, Douglas J.; Gaunt, Robert A.

    2014-06-01

    Objective. This study describes results of primary afferent neural microstimulation experiments using microelectrode arrays implanted chronically in the lumbar dorsal root ganglia (DRG) of four cats. The goal was to test the stability and selectivity of these microelectrode arrays as a potential interface for restoration of somatosensory feedback after damage to the nervous system such as amputation. Approach. A five-contact nerve-cuff electrode implanted on the sciatic nerve was used to record the antidromic compound action potential response to DRG microstimulation (2-15 µA biphasic pulses, 200 µs cathodal pulse width), and the threshold for eliciting a response was tracked over time. Recorded responses were segregated based on conduction velocity to determine thresholds for recruiting Group I and Group II/Aβ primary afferent fibers. Main results. Thresholds were initially low (5.1 ± 2.3 µA for Group I and 6.3 ± 2.0 µA for Group II/Aβ) and increased over time. Additionally the number of electrodes with thresholds less than or equal to 15 µA decreased over time. Approximately 12% of tested electrodes continued to elicit responses at 15 µA up to 26 weeks after implantation. Higher stimulation intensities (up to 30 µA) were tested in one cat at 23 weeks post-implantation yielding responses on over 20 additional electrodes. Within the first six weeks after implantation, approximately equal numbers of electrodes elicited only Group I or Group II/Aβ responses at threshold, but the relative proportion of Group II/Aβ responses decreased over time. Significance. These results suggest that it is possible to activate Group I or Group II/Aβ primary afferent fibers in isolation with penetrating microelectrode arrays implanted in the DRG, and that those responses can be elicited up to 26 weeks after implantation, although it may be difficult to achieve a consistent response day-to-day with currently available electrode technology. The DRG are compelling targets

  1. Transient inflammation-induced ongoing pain is driven by TRPV1 sensitive afferents

    Directory of Open Access Journals (Sweden)

    Mercado Ramon

    2011-01-01

    Full Text Available Abstract Background Tissue injury elicits both hypersensitivity to evoked stimuli and ongoing, stimulus-independent pain. We previously demonstrated that pain relief elicits reward in nerve-injured rats. This approach was used to evaluate the temporal and mechanistic features of inflammation-induced ongoing pain. Results Intraplantar Complete Freund's Adjuvant (CFA produced thermal hyperalgesia and guarding behavior that was reliably observed within 24 hrs and maintained, albeit diminished, 4 days post-administration. Spinal clonidine produced robust conditioned place preference (CPP in CFA treated rats 1 day, but not 4 days following CFA administration. However, spinal clonidine blocked CFA-induced thermal hyperalgesia at both post-CFA days 1 and 4, indicating different time-courses of ongoing and evoked pain. Peripheral nerve block by lidocaine administration into the popliteal fossa 1 day following intraplantar CFA produced a robust preference for the lidocaine paired chamber, indicating that injury-induced ongoing pain is driven by afferent fibers innervating the site of injury. Pretreatment with resiniferatoxin (RTX, an ultrapotent capsaicin analogue known to produce long-lasting desensitization of TRPV1 positive afferents, fully blocked CFA-induced thermal hypersensitivity and abolished the CPP elicited by administration of popliteal fossa lidocaine 24 hrs post-CFA. In addition, RTX pretreatment blocked guarding behavior observed 1 day following intraplantar CFA. In contrast, administration of the selective TRPV1 receptor antagonist, AMG9810, at a dose that reversed CFA-induced thermal hyperalgesia failed to reduce CFA-induced ongoing pain or guarding behavior. Conclusions These data demonstrate that inflammation induces both ongoing pain and evoked hypersensitivity that can be differentiated on the basis of time course. Ongoing pain (a is transient, (b driven by peripheral input resulting from the injury, (c dependent on TRPV1 positive

  2. Gait phase detection from sciatic nerve recordings in functional electrical stimulation systems for foot drop correction

    International Nuclear Information System (INIS)

    Chu, Jun-Uk; Song, Kang-Il; Han, Sungmin; Suh, Jun-Kyo Francis; Choi, Kuiwon; Youn, Inchan; Lee, Soo Hyun; Kang, Ji Yoon; Hwang, Dosik

    2013-01-01

    Cutaneous afferent activities recorded by a nerve cuff electrode have been used to detect the stance phase in a functional electrical stimulation system for foot drop correction. However, the implantation procedure was difficult, as the cuff electrode had to be located on the distal branches of a multi-fascicular nerve to exclude muscle afferent and efferent activities. This paper proposes a new gait phase detection scheme that can be applied to a proximal nerve root that includes cutaneous afferent fibers as well as muscle afferent and efferent fibers. To test the feasibility of this scheme, electroneurogram (ENG) signals were measured from the rat sciatic nerve during treadmill walking at several speeds, and the signal properties of the sciatic nerve were analyzed for a comparison with kinematic data from the ankle joint. On the basis of these experiments, a wavelet packet transform was tested to define a feature vector from the sciatic ENG signals according to the gait phases. We also propose a Gaussian mixture model (GMM) classifier and investigate whether it could be used successfully to discriminate feature vectors into the stance and swing phases. In spite of no significant differences in the rectified bin-integrated values between the stance and swing phases, the sciatic ENG signals could be reliably classified using the proposed wavelet packet transform and GMM classification methods. (paper)

  3. Airway inflammation and tachykinins: prospects for the development of tachykinin receptor antagonists.

    Science.gov (United States)

    Joos, G F; De Swert, K O; Pauwels, R A

    2001-10-19

    The tachykinins substance P and neurokinin A are contained within sensory airway nerves. Immune cells form an additional source of tachykinins in inflamed airways. Elevated levels of tachykinins have been recovered from the airways of patients with asthma and chronic obstructive pulmonary disease. Airway inflammation leads to an upregulation of tachykinin NK(1) and NK(2) receptors. Preclinical studies have indicated a role for the tachykinin NK(1), NK(2) and NK(3) receptors in bronchoconstriction, airway hyperresponsiveness and airway inflammation caused by allergic and nonallergic stimuli. Compounds that are able to block two or three tachykinin receptors hold promise for the treatment of airways diseases such as asthma and/or chronic obstructive pulmonary disease.

  4. Effects of pharyngeal lubrication on the opening of obstructed upper airway.

    Science.gov (United States)

    Miki, H; Hida, W; Kikuchi, Y; Chonan, T; Satoh, M; Iwase, N; Takishima, T

    1992-06-01

    We examined the effect of electrical stimulation of the hypoglossal nerve and pharyngeal lubrication with artificial surfactant (Surfactant T-A) on the opening of obstructed upper airway in nine anesthetized supine dogs. The upper airway was isolated from the lower airway by transecting the cervical trachea. Upper airway obstruction was induced by applying constant negative pressures (5, 10, 20, and 30 cmH2O) on the rostral cut end of the trachea. Peripheral cut ends of the hypoglossal nerves were electrically stimulated by square-wave pulses at various frequencies from 10 to 30 Hz (0.2-ms duration, 5-7 V), and the critical stimulating frequency necessary for opening the obstructed upper airway was measured at each driving pressure before and after pharyngeal lubrication with artificial surfactant. The critical stimulation frequency for upper airway opening significantly increased as upper airway pressure became more negative and significantly decreased with lubrication of the upper airway. These findings suggest that greater muscle tone of the genioglossus is needed to open the occluded upper airway with larger negative intraluminal pressure and that lubrication of the pharyngeal mucosa with artificial surfactant facilitates reopening of the upper airway.

  5. Low-dimensional sensory feature representation by trigeminal primary afferents.

    Science.gov (United States)

    Bale, Michael R; Davies, Kyle; Freeman, Oliver J; Ince, Robin A A; Petersen, Rasmus S

    2013-07-17

    In any sensory system, the primary afferents constitute the first level of sensory representation and fundamentally constrain all subsequent information processing. Here, we show that the spike timing, reliability, and stimulus selectivity of primary afferents in the whisker system can be accurately described by a simple model consisting of linear stimulus filtering combined with spike feedback. We fitted the parameters of the model by recording the responses of primary afferents to filtered, white noise whisker motion in anesthetized rats. The model accurately predicted not only the response of primary afferents to white noise whisker motion (median correlation coefficient 0.92) but also to naturalistic, texture-induced whisker motion. The model accounted both for submillisecond spike-timing precision and for non-Poisson spike train structure. We found substantial diversity in the responses of the afferent population, but this diversity was accurately captured by the model: a 2D filter subspace, corresponding to different mixtures of position and velocity sensitivity, captured 94% of the variance in the stimulus selectivity. Our results suggest that the first stage of the whisker system can be well approximated as a bank of linear filters, forming an overcomplete representation of a low-dimensional feature space.

  6. Afferent Pathway-Mediated Effect of α1 Adrenergic Antagonist, Tamsulosin, on the Neurogenic Bladder After Spinal Cord Injury.

    Science.gov (United States)

    Han, Jin-Hee; Kim, Sung-Eun; Ko, Il-Gyu; Kim, Jayoung; Kim, Khae Hawn

    2017-09-01

    The functions of the lower urinary tract (LUT), such as voiding and storing urine, are dependent on complex central neural networks located in the brain, spinal cord, and peripheral ganglia. Thus, the functions of the LUT are susceptible to various neurologic disorders including spinal cord injury (SCI). SCI at the cervical or thoracic levels disrupts voluntary control of voiding and the normal reflex pathways coordinating bladder and sphincter functions. In this context, it is noteworthy that α1-adrenoceptor blockers have been reported to relieve voiding symptoms and storage symptoms in elderly men with benign prostatic hyperplasia (BPH). Tamsulosin, an α1-adrenoceptor blocker, is also considered the most effective regimen for patients with LUT symptoms such as BPH and overactive bladder (OAB). In the present study, the effects of tamsulosin on the expression of c-Fos, nerve growth factor (NGF), and nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) in the afferent micturition areas, including the pontine micturition center (PMC), the ventrolateral periaqueductal gray matter (vlPAG), and the spinal cord (L5), of rats with an SCI were investigated. SCI was found to remarkably upregulate the expression of c-Fos, NGF, and NADPH-d in the afferent pathway of micturition, the dorsal horn of L5, the vlPAG, and the PMC, resulting in the symptoms of OAB. In contrast, tamsulosin treatment significantly suppressed these neural activities and the production of nitric oxide in the afferent pathways of micturition, and consequently, attenuated the symptoms of OAB. Based on these results, tamsulosin, an α1-adrenoceptor antagonist, could be used to attenuate bladder dysfunction following SCI. However, further studies are needed to elucidate the exact mechanism and effects of tamsulosin on the afferent pathways of micturition.

  7. Cervical vagus nerve stimulation augments spontaneous discharge in second- and higher-order sensory neurons in the rat nucleus of the solitary tract.

    Science.gov (United States)

    Beaumont, Eric; Campbell, Regenia P; Andresen, Michael C; Scofield, Stephanie; Singh, Krishna; Libbus, Imad; KenKnight, Bruce H; Snyder, Logan; Cantrell, Nathan

    2017-08-01

    Vagus nerve stimulation (VNS) currently treats patients with drug-resistant epilepsy, depression, and heart failure. The mild intensities used in chronic VNS suggest that primary visceral afferents and central nervous system activation are involved. Here, we measured the activity of neurons in the nucleus of the solitary tract (NTS) in anesthetized rats using clinically styled VNS. Our chief findings indicate that VNS at threshold bradycardic intensity activated NTS neuron discharge in one-third of NTS neurons. This VNS directly activated only myelinated vagal afferents projecting to second-order NTS neurons. Most VNS-induced activity in NTS, however, was unsynchronized to vagal stimuli. Thus, VNS activated unsynchronized activity in NTS neurons that were second order to vagal afferent C-fibers as well as higher-order NTS neurons only polysynaptically activated by the vagus. Overall, cardiovascular-sensitive and -insensitive NTS neurons were similarly activated by VNS: 3/4 neurons with monosynaptic vagal A-fiber afferents, 6/42 neurons with monosynaptic vagal C-fiber afferents, and 16/21 polysynaptic NTS neurons. Provocatively, vagal A-fibers indirectly activated C-fiber neurons during VNS. Elevated spontaneous spiking was quantitatively much higher than synchronized activity and extended well into the periods of nonstimulation. Surprisingly, many polysynaptic NTS neurons responded to half the bradycardic intensity used in clinical studies, indicating that a subset of myelinated vagal afferents is sufficient to evoke VNS indirect activation. Our study uncovered a myelinated vagal afferent drive that indirectly activates NTS neurons and thus central pathways beyond NTS and support reconsideration of brain contributions of vagal afferents underpinning of therapeutic impacts. NEW & NOTEWORTHY Acute vagus nerve stimulation elevated activity in neurons located in the medial nucleus of the solitary tract. Such stimuli directly activated only myelinated vagal afferents

  8. Induction of CB1 cannabinoid receptor by inflammation in primary afferent neurons facilitates antihyperalgesic effect of peripheral CB1 agonist.

    Science.gov (United States)

    Amaya, Fumimasa; Shimosato, Goshun; Kawasaki, Yasuhiko; Hashimoto, Satoru; Tanaka, Yoshifumi; Ji, Ru-Rong; Tanaka, Masaki

    2006-09-01

    Cannabinoids act on various regions in the nervous system to modulate neuronal activity including nociception. Here, we investigated CB1 receptor expression in primary afferent neurons in the dorsal root ganglion (DRG) and the efficacy of a local (intraplantar) application of the selective CB1 agonist, 2-arachidonyl-2-chloroethylamide (ACEA), on inflammatory thermal hyperalgesia. In situ hybridization showed normal CB1 mRNA expression in 28% of DRG neurons. Peripheral inflammation by CFA (complete Freund's adjuvant) significantly increased the ratio of CB1 mRNA-positive neurons to 43%, primarily with increase in NF200-negative C-fiber nociceptors. Furthermore, CB1 and TRPV1 (transient potential receptor vanilloid subtype-1) co-localization was increased from 41% before inflammation to 67% two days after inflammation. Inflammation also increased CB1 immunoreactivity in DRG neurons and in nerve fibers of the hindpaw dermis, indicating increased CB1 transport from the cell body to the peripheral nerve. The intraplantar application of ACEA attenuated CFA-induced thermal hyperalgesia. The antinociceptive properties of ACEA became more prominent at 2 days after inflammation, compared with those in non-inflamed and inflamed animals at 8 h. These results suggest that CB1 expression in primary afferent neurons is increased by inflammation and that the subsequent increase in CB1 transport to peripheral axons contributes to the increased antihyperalgesic efficacy of locally administered CB1 agonist.

  9. Engineering Airway Epithelium

    Directory of Open Access Journals (Sweden)

    John P. Soleas

    2012-01-01

    Full Text Available Airway epithelium is constantly presented with injurious signals, yet under healthy circumstances, the epithelium maintains its innate immune barrier and mucociliary elevator function. This suggests that airway epithelium has regenerative potential (I. R. Telford and C. F. Bridgman, 1990. In practice, however, airway regeneration is problematic because of slow turnover and dedifferentiation of epithelium thereby hindering regeneration and increasing time necessary for full maturation and function. Based on the anatomy and biology of the airway epithelium, a variety of tissue engineering tools available could be utilized to overcome the barriers currently seen in airway epithelial generation. This paper describes the structure, function, and repair mechanisms in native epithelium and highlights specific and manipulatable tissue engineering signals that could be of great use in the creation of artificial airway epithelium.

  10. Human airway smooth muscle

    OpenAIRE

    Jongste, Johan

    1987-01-01

    textabstractThe function of airway smooth muscle in normal subjects is not evident. Possible physiological roles include maintenance of optimal regional ventilation/perfusion ratios, reduction of anatomic dead space, stabilisation of cartilaginous bronchi, defense against impurities and, less likely, squeezing mucus out of mucous glands and pulling open the alveoli next to the airways1 . Any role of airway smooth muscle is necessarily limited, because an important degree of contraction will l...

  11. Normal tendon reflexes despite absent sensory nerve action potentials in CANVAS: a neurophysiological study.

    Science.gov (United States)

    Burke, David; Michael Halmagyi, G

    2018-04-15

    CANVAS is a recently defined progressive ataxic syndrome with impairment of vestibular, somatosensory and cerebellar function due to atrophic degeneration of dorsal root ganglia and dorsal columns, of cranial nerve somatosensory ganglia, of vestibular ganglia and vestibular nerves and of cerebellar Purkinje cells. While all patients eventually develop sensory impairment in a non-length dependent pattern and lose sensory nerve action potentials, some retain their tendon reflexes. Here we study 5 CANVAS patients with absent sensory nerve action potentials but intact, even brisk Achilles tendon reflexes and, in 4, preserved H reflexes in the upper and lower limbs. These findings imply that dorsal root ganglion neurons subserving cutaneous afferents more vulnerable than those subserving muscle afferents. Our findings have a clinical message: preservation of the Achilles tendon jerk does not exclude a large fibre peripheral neuronopathy. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Rhinovirus and airway allergy

    Directory of Open Access Journals (Sweden)

    Mutsuo Yamaya

    2004-01-01

    Full Text Available Rhinoviruses cause the majority of common colds, which often provoke wheezing in patients with asthma. The precise mechanisms responsible for the rhinovirus infection-induced exacerbations of bronchial asthma remain uncertain. However, several reports have demonstrated airway hyperresponsiveness, increases in chemical mediators in airway secretions, such as kinin and histamine, and airway inflammation in patients with bronchial asthma after rhinovirus infection. Rhinovirus infection induces the accumulation of inflammatory cells in airway mucosa and submucosa, including neutrophils, lymphocytes and eosinophils. Rhinovirus affects the barrier function of airway epithelial cells and activates airway epithelial cells and other cells in the lung to produce proinflammatory cytokines, including various types of interleukins, granulocyte-macrophage colony stimulating factor and RANTES, and histamine. Rhinovirus also stimulates the expression of intercellular adhesion molecule-1 (ICAM-1 and low-density lipoprotein receptors in the airway epithelium, receptors for major and minor rhinoviruses. Rhinovirus infection is inhibited by treatment with soluble ICAM-1 and by the reduction of ICAM-1 expression in airway epithelial cells after treatment with either glucocorticoid or erythromycin. Both soluble ICAM-1 and erythromycin have been reported to reduce the symptoms of common colds. Herein, we review the pathogenesis and management of rhinovirus infection-induced exacerbation of bronchial asthma and the relationship between rhinovirus infection and airway allergy.

  13. [Regeneration of airway epithelium].

    Science.gov (United States)

    Adam, D; Perotin, J-M; Lebargy, F; Birembaut, P; Deslée, G; Coraux, C

    2014-04-01

    Epithelial regeneration is a complex process. It can lead to the remodeling of the airway epithelium as in asthma, COPD or cystic fibrosis. The development of in vivo and in vitro models has allowed the analysis of remodeling mechanisms and showed the role of components of extracellular matrix, proteases, cytokines and growth factors. Airway epithelial progenitors and stems cells have been studied in these models. However, their identification remains difficult. Identification and characterization of airway epithelial progenitor/stem-cells, and a better knowledge of the regeneration process may allow the development of new therapeutic strategies for airway epithelial reconstitution. Copyright © 2013 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  14. Termination of trigeminal primary afferents on glossopharyngeal-vagal motoneurons: possible neural networks underlying the swallowing phase and visceromotor responses of prey-catching behavior.

    Science.gov (United States)

    Kecskes, Szilvia; Matesz, Clara; Birinyi, András

    2013-10-01

    Prey-catching behavior (PCB) of the frog consists of a sequence of coordinated activity of muscles which is modified by various sensory signals. The aim of the present study was, for the first time, to examine the involvement of the trigeminal afferents in the swallowing phase of PCB. Experiments were performed on Rana esculenta, where the trigeminal and glossopharyngeal (IX)-vagus (X) nerves were labeled simultaneously with different fluorescent dyes. Using confocal laser scanning microscope, close appositions were detected between the trigeminal afferent fibers and somatodendritic components of the IX-X motoneurons of the ambiguus nucleus (NA). Neurolucida reconstruction revealed spatial distribution of the trigeminal afferents in the functionally different parts of the NA. Thus, the visceromotor neurons supplying the stomach, the heart and the lung received about two third of the trigeminal contacts followed by the pharyngomotor and then by the laryngomotor neurons. On the other hand, individual motoneurons responsible for innervation of the viscera received less trigeminal terminals than the neurons supplying the muscles of the pharynx. The results suggest that the direct contacts between the trigeminal afferents and IX-X motoneurons presented here may be one of the morphological substrate of a very quick response during the swallowing phase of PCB. Combination of direct and indirect trigeminal inputs may contribute to optimize the ongoing motor execution. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Asymmetric Macular Structural Damage Is Associated With Relative Afferent Pupillary Defects in Patients With Glaucoma

    Science.gov (United States)

    Gracitelli, Carolina P. B.; Tatham, Andrew J.; Zangwill, Linda M.; Weinreb, Robert N.; Abe, Ricardo Y.; Diniz-Filho, Alberto; Paranhos, Augusto; Baig, Saif; Medeiros, Felipe A.

    2016-01-01

    Purpose We examined the relationship between relative afferent pupillary defects (RAPDs) and macular structural damage measured by macular thickness and macular ganglion cell-inner plexiform layer (mGCIPL) thickness in patients with glaucoma. Methods A cross-sectional study was done of 106 glaucoma patients and 85 healthy individuals from the Diagnostic Innovations in Glaucoma Study. All subjects underwent standard automated perimetry (SAP) and optic nerve and macular imaging using Cirrus Spectral Domain Optical Coherence Tomography (SDOCT). Glaucoma was defined as repeatable abnormal SAP or progressive glaucomatous changes on stereo photographs. Pupil responses were assessed using an automated pupillometer, which records the magnitude of RAPD (RAPD score), with additional RAPD scores recorded for each of a series of colored stimuli (blue, red, green, and yellow). The relationship between RAPD score and intereye differences (right minus left eye) in circumpapillary retinal nerve fiber layer (cpRNFL) thickness, mGCIPL, macular thickness, and SAP mean deviation (MD), was examined using linear regression. Results There was fair correlation between RAPD score and asymmetric macular structural damage measured by intereye difference in mGCIPL thickness (R2 = 0.285, P glaucoma. PMID:27064394

  16. Early use of artificial sensibility to improve sensory recovery after repair of the median and ulnar nerve.

    Science.gov (United States)

    Rosén, Birgitta; Lundborg, Göran

    2003-01-01

    Artificial sensibility based on use of a "tactile glove" which substitutes for lack of sensory afferent inflow with acoustic feedback, was used early after repair of the median and ulnar nerves in a 21-year-old man. After six and 12 months the functional outcome exceeded what is expected in adults, and analysis with calculations for the minimal detectable change (MDC) in tactile gnosis showed a true change. This case highlights the timing of sensory re-education after nerve repair and also emphasises the importance of early restitution of afferent inflow from a denervated hand during rehabilitation.

  17. Airway distensibility in Chronic Obstructive Airway Disease

    DEFF Research Database (Denmark)

    Winkler Wille, Mathilde Marie; Pedersen, Jesper Holst; Dirksen, Asger

    2013-01-01

    -20% (mild), 20%-30% (moderate) or >30% (severe). Spirometry was performed annually and participants were divided into severity groups according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD). Data were analysed in a mixed effects regression model with log(airway lumen diameter...... the interior and exterior airway wall surface in three dimensions, and branches were matched in consecutive scans by image registration. Emphysema was defined as attenuation referred to as % low-attenuation area 910 (%LAA910). Emphysema limits were set at

  18. Airway smooth muscle cells : regulators of airway inflammation

    NARCIS (Netherlands)

    Zuyderduyn, Suzanne

    2007-01-01

    Airways from asthmatic subjects are more responsive to bronchoconstrictive stimuli than airways from healthy subjects. Airway smooth muscle (ASM) cells mediate contraction of the airways by responding to the bronchoconstrictive stimuli, which was thought to be the primary role of ASM cells. In this

  19. Relationship between airway pathophysiology and airway inflammation in older asthmatics

    DEFF Research Database (Denmark)

    Porsbjerg, Celeste M; Gibson, Peter G; Pretto, Jeffrey J

    2013-01-01

    , neutrophil airway inflammation increases airway closure during bronchoconstriction, while eosinophil airway inflammation increases airway hyperresponsiveness (AHR). METHODS: Asthmatic subjects (n = 26), aged ≥55 years (68% female), were studied, and AHR to 4.5% saline challenge was measured by the response...... or eNO. CONCLUSIONS: In older patients with asthma, airway inflammatory cells are linked to abnormal airway physiology. Eosinophilic airway inflammation is associated with AHR while neutrophilic inflammation may be an important determinant of airflow limitation at rest and airway closure during......BACKGROUND AND OBJECTIVE: Asthma-related morbidity is greater in older compared with younger asthmatics. Airway closure is also greater in older asthmatics, an observation that may be explained by differences in airway inflammation. We hypothesized that in older adult patients with asthma...

  20. Recording nerve signals in canine sciatic nerves with a flexible penetrating microelectrode array

    Science.gov (United States)

    Byun, Donghak; Cho, Sung-Joon; Lee, Byeong Han; Min, Joongkee; Lee, Jong-Hyun; Kim, Sohee

    2017-08-01

    Objective. Previously, we presented the fabrication and characterization of a flexible penetrating microelectrode array (FPMA) as a neural interface device. In the present study, we aim to prove the feasibility of the developed FPMA as a chronic intrafascicular recording tool for peripheral applications. Approach. For recording from the peripheral nerves of medium-sized animals, the FPMA was integrated with an interconnection cable and other parts that were designed to fit canine sciatic nerves. The uniformity of tip exposure and in vitro electrochemical properties of the electrodes were characterized. The capability of the device to acquire in vivo electrophysiological signals was evaluated by implanting the FPMA assembly in canine sciatic nerves acutely as well as chronically for 4 weeks. We also examined the histology of implanted tissues to evaluate the damage caused by the device. Main results. Throughout recording sessions, we observed successful multi-channel recordings (up to 73% of viable electrode channels) of evoked afferent and spontaneous nerve unit spikes with high signal quality (SNR  >  4.9). Also, minor influences of the device implantation on the morphology of nerve tissues were found. Significance. The presented results demonstrate the viability of the developed FPMA device in the peripheral nerves of medium-sized animals, thereby bringing us a step closer to human applications. Furthermore, the obtained data provide a driving force toward a further study for device improvements to be used as a bidirectional neural interface in humans.

  1. Upper Airway Control in Airway Defense

    Directory of Open Access Journals (Sweden)

    Poliacek I

    2016-04-01

    Full Text Available Upper airways (UA are an organic component of the respiratory tract, they serve to respiration, respiratory tract protection and defense, phonation, deglutition, etc. The functions of UA are regulated by motor control of the oral, pharyngeal, and laryngeal muscles.

  2. Airway distensibility in Chronic Obstructive Airway Disease

    DEFF Research Database (Denmark)

    Winkler Wille, Mathilde Marie; Pedersen, Jesper Holst; Dirksen, Asger

    2013-01-01

    on the airway distensibility, defined as the ratio of relative change in lumen diameter to the relative change in total lung volume (TLV) divided by predicted total lung capacity (pTLC) . Methods – We included 1900 participants from the Danish Lung Cancer Screening Trial (DLCST); all randomized to annual low...

  3. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... people with cystic fibrosis so that they make smart decisions about CF-related research, treatment, and access ... Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home Life With CF Treatments and Therapies Airway Clearance ...

  4. Airway Clearance Techniques (ACTs)

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    Full Text Available ... Clinician Career Development Awards Clinician Training Awards Mutation Analysis Program Network News Network News: January 2018 Network ... for airway clearance. Facebook Twitter Email More Related Content Medications Autogenic Drainage Positive Expiratory Pressure High-Frequency ...

  5. Airway Clearance Techniques (ACTs)

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    Full Text Available ... a Family Parenting as an Adult With CF Treatments & Therapies People with cystic fibrosis are living longer ... to specialized CF care and a range of treatment options. Airway Clearance Active Cycle of Breathing Technique ...

  6. Airway Clearance Techniques (ACTs)

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    Full Text Available ... another member of your CF care team can show you how to perform many different ACTs and ... of children with CF and a respiratory therapist talk about the different techniques they use for airway ...

  7. Airway Clearance Techniques (ACTs)

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    Full Text Available ... There are different ways to clear your airways. Most are easy to do. Infants and toddlers will ... best ACT is the one that you are most likely to perform as part of your daily ...

  8. Airway Clearance Techniques (ACTs)

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    Full Text Available ... CYSTIC FIBROSIS Learn about cystic fibrosis, a genetic lung disorder that affects the pancreas and other organs, ... Technique Airway Clearance Techniques Autogenic Drainage Basics of Lung Care Chest Physical Therapy Coughing and Huffing High- ...

  9. Airway protective mechanisms.

    Science.gov (United States)

    Pitts, Teresa

    2014-02-01

    Cough and swallow are highly coordinated reflex behaviors whose common purpose is to protect the airway. The pharynx is the common tube for air and food/liquid movement from the mouth into the thorax, has been largely overlooked, and is potentially seen as just a passive space. The thyropharyngeus muscle responds to cough inducing stimuli to prepare a transient holding area for material that has been removed from the subglottic airway. The cricopharyngeus muscle participates with the larynx to ensure regulation of pressure when a bolus/air is moving from the upper airway through to the thorax (i.e., inspiration or swallow) or the reverse (i.e., expiration reflex or vomiting). These vital mechanisms have not been evaluated in clinical conditions but could be impaired in many neurodegenerative diseases, leading to aspiration pneumonia. These newly described airway protective mechanisms need further study, especially in healthy and pathologic human populations.

  10. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Clinical Care Guidelines Liver Disease Clinical Care Guidelines Respiratory Care Guidelines CF Airway Clearance Therapies Clinical Care ... attack bacteria. Choose What's Best for You Your respiratory therapist or another member of your CF care ...

  11. Airway Clearance Techniques (ACTs)

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    Full Text Available ... Cycle of Breathing Technique Airway Clearance Techniques Autogenic Drainage Basics of Lung Care Chest Physical Therapy Coughing ... Facebook Twitter Email More Related Content Medications Autogenic Drainage Positive Expiratory Pressure High-Frequency Chest Wall Oscillation ( ...

  12. Airway Clearance Techniques (ACTs)

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    Full Text Available ... CFTR Modulator Therapies Mucus Thinners Nebulizer Care at Home Vascular Access Devices PICCs and Ports Partnerships for ... Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home Life With CF Treatments and Therapies Airway Clearance ...

  13. Human airway smooth muscle

    NARCIS (Netherlands)

    J.C. de Jongste (Johan)

    1987-01-01

    textabstractThe function of airway smooth muscle in normal subjects is not evident. Possible physiological roles include maintenance of optimal regional ventilation/perfusion ratios, reduction of anatomic dead space, stabilisation of cartilaginous bronchi, defense against impurities and, less

  14. Airway Clearance Techniques (ACTs)

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    Full Text Available ... many challenges, including medical, social, and financial. By learning more about how you can manage your disease every day, you can ultimately help find a ... Cycle of Breathing Technique Airway Clearance Techniques Autogenic ...

  15. Airway Clearance Techniques (ACTs)

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    Full Text Available ... today. ANNUAL FUND Become a Corporate Supporter Cause Marketing Make a Charitable Gift Our Corporate Supporters Workplace ... for airway clearance. Facebook Twitter Email More Related Content Medications Autogenic Drainage Positive Expiratory Pressure High-Frequency ...

  16. Airway Clearance Techniques (ACTs)

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    Full Text Available ... the smaller airways to attack bacteria. Choose What's Best for You Your respiratory therapist or another member ... specific ACTs for you to try. However, the best ACT is the one that you are most ...

  17. Airway Clearance Techniques (ACTs)

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    Full Text Available ... in CF Clinical Care Guidelines Cystic Fibrosis-Related Diabetes Clinical Care Guidelines Liver Disease Clinical Care Guidelines Respiratory Care Guidelines CF Airway Clearance Therapies Clinical Care Guidelines Chronic Medications to Maintain Lung ...

  18. Giant renin secretory granules in beige mouse renal afferent arterioles

    DEFF Research Database (Denmark)

    Jensen, B L; Rasch, Ruth; Nyengaard, Jens Randel

    1997-01-01

    The mutant beige mouse (C57BL/6 bg) has a disease characterised by abnormally enlarged cytoplasmic granules in a variety of cells. With the purpose of establishing a suitable cellular model for studying renin secretion, the present study was undertaken to compare renin granule morphology in beige.......5+/-0.3 mGoldblatt units/ml). The total volume of renin granules per afferent arteriole was similar in the two mice strains (1114 microm3 in the controls and 1507 microm3 in the beige mice). The total number of renin granules per arteriole as assessed by stereological techniques was about 1900 in controls...... (average granular volume 0.681 microm3), whereas 1-2 large granules were present per cell in beige mice. The volume of afferent arteriole that contained secretory granules was lower in the beige mice. We conclude that the beige mouse synthesizes, stores and releases active renin. Renin secretory granules...

  19. Muscle weakness, afferent sensory dysfunction and exercise in knee osteoarthritis

    DEFF Research Database (Denmark)

    Roos, Ewa M.; Herzog, Walter; Block, Joel A

    2011-01-01

    Lower-extremity muscle strength and afferent sensory dysfunction, such as reduced proprioceptive acuity, are potentially modifiable putative risk factors for knee osteoarthritis (OA). Findings from current studies suggest that muscle weakness is a predictor of knee OA onset, while there is confli...... with previous knee injuries) are easily identified, and may benefit from exercise interventions to prevent or delay OA onset....... there is conflicting evidence regarding the role of muscle weakness in OA progression. In contrast, the literature suggests a role for afferent sensory dysfunction in OA progression but not necessarily in OA onset. The few pilot exercise studies performed in patients who are at risk of incident OA indicate...... a possibility for achieving preventive structure or load modifications. In contrast, large randomized controlled trials of patients with established OA have failed to demonstrate beneficial effects of strengthening exercises. Subgroups of individuals who are at increased risk of knee OA (such as those...

  20. Cooling reduces the cutaneous afferent firing response to vibratory stimuli in glabrous skin of the human foot sole.

    Science.gov (United States)

    Lowrey, Catherine R; Strzalkowski, Nicholas D J; Bent, Leah R

    2013-02-01

    Skin on the foot sole plays an important role in postural control. Cooling the skin of the foot is often used to induce anesthesia to determine the role of skin in motor and balance control. The effect of cooling on the four classes of mechanoreceptor in the skin is largely unknown, and thus the aim of the present study was to characterize the effects of cooling on individual skin receptors in the foot sole. Such insight will better isolate individual receptor contributions to balance control. Using microneurography, we recorded 39 single nerve afferents innervating mechanoreceptors in the skin of the foot sole in humans. Afferents were identified as fast-adapting (FA) or slowly adapting (SA) type I or II (FA I n = 16, FA II n = 7, SA I n = 6, SA II n = 11). Receptor response to vibration was compared before and after cooling of the receptive field (2-20 min). Overall, firing response was abolished in 30% of all receptors, and this was equally distributed across receptor type (P = 0.69). Longer cooling times were more likely to reduce firing response below 50% of baseline; however, some afferent responses were abolished with shorter cooling times (2-5 min). Skin temperature was not a reliable indicator of the level of receptor activation and often became uncoupled from receptor response levels, suggesting caution in the use of this parameter as an indicator of anesthesia. When cooled, receptors preferentially coded lower frequencies in response to vibration. In response to a sustained indentation, SA receptors responded more like FA receptors, primarily coding "on-off" events.

  1. Bradykinin Contributes to Sympathetic and Pressor Responses Evoked by Activation of Skeletal Muscle Afferents P2X in Heart Failure

    Directory of Open Access Journals (Sweden)

    Jihong Xing

    2016-11-01

    Full Text Available Background/Aims: Published data suggest that purinergic P2X receptors of muscle afferent nerves contribute to the enhanced sympathetic nervous activity (SNA and blood pressure (BP responses during static exercise in heart failure (HF. In this study, we examined engagement of bradykinin (BK in regulating responses of SNA and BP evoked by P2X stimulation in rats with HF. We further examined cellular mechanisms responsible for BK. We hypothesized that BK potentiates P2X currents of muscle dorsal root ganglion (DRG neurons, and this effect is greater in HF due to upregulation of BK kinin B2 and P2X3 receptor. As a result, BK amplifies muscle afferents P2X-mediated SNA and BP responses. Methods: Renal SNA and BP responses were recorded in control rats and rats with HF. Western Blot analysis and patch-clamp methods were employed to examine the receptor expression and function of DRG neurons involved in the effects of BK. Results: BK injected into the arterial blood supply of the hindlimb muscles heightened the reflex SNA and BP responses induced by P2X activation with α,β-methylene ATP to a greater degree in HF rats. In addition, HF upregulated the protein expression of kinin B2 and P2X3 in DRG and the prior application of BK increased the magnitude of α,β-methylene ATP-induced currents in muscle DRG neurons from HF rats. Conclusion: BK plays a facilitating role in modulating muscle afferent P2X-engaged reflex sympathetic and pressor responses. In HF, P2X responsivness is augmented due to increases in expression of kinin B2 and P2X3 receptors and P2X current activity.

  2. Cerebro-afferent vessel and pupillary basal diameter variation induced by stomatognathic trigeminal proprioception: a case report.

    Science.gov (United States)

    De Cicco, Vincenzo

    2012-09-03

    A patient affected by asymmetric hemodynamics of cerebro-afferent vessels underwent duplex color scanner investigations in occlusal proprioceptive un- and rebalance conditions. Pupillometric video-oculographic examinations were performed in order to spot connected trigeminal proprioceptive motor patterns able to interfere on sympathetic autonomic activity. The aim of this case report is to verify if involuntary jaw closing during swallowing, executed in unbalance and rebalance myoelectric activity, would be able to modify cerebral hemodynamics. A 56-year-old Caucasian Italian woman affected by asymmetric blood flow of cerebro-afferent vessels underwent an electromyographic investigation of her occlusal muscles in order to assess their occlusal functional balance. The extreme asymmetry of myoelectric activity in dental occlusion evidenced by electromyographic values suggested the rebalancing of the functions of occlusal muscles through concurrent transcutaneous stimulation of the trigeminal nerve supra- and submandibular motor branches. The above-mentioned method allowed the detection of a symmetric craniomandibular muscular relation that can be kept constant through the use of a cusp bite modeled on the inferior dental arch: called orthotic-syntropic bite for its peculiar use of electrostimulation. A few days later, the patient underwent a duplex color scanner investigation and pupillometric video-oculographic examinations in occlusal unbalance and rebalance conditions. A comparative data analysis showed that an unbalanced dental occlusal function may represent an interferential pattern on cerebral hemodynamics velocity and pupillometric evaluations have proved useful both in the analysis of locus coeruleus functional modalities and as a diagnostic tool in the assessment of pathologies involving locus coeruleus and autonomic systems. The inclusion of myoelectric masseter examinations can be useful in patients with asymmetric hemodynamics of cerebro-afferent

  3. Airway Protective Mechanisms

    OpenAIRE

    Pitts, Teresa

    2013-01-01

    Cough and swallow are highly coordinated reflex behaviors whose common purpose is to protect the airway. The pharynx is the common tube for air and food/liquid movement from the mouth into the thorax, has been largely overlooked, and is potentially seen as just a passive space. The thyropharyngeus muscle responds to cough inducing stimuli to prepare a transient holding area for material that has been removed from the subglottic airway. The cricopharyngeus muscle participates with the larynx t...

  4. Urothelial Tight Junction Barrier Dysfunction Sensitizes Bladder Afferents

    Science.gov (United States)

    Rued, Anna C.; Taiclet, Stefanie N.; Birder, Lori A.; Kullmann, F. Aura

    2017-01-01

    Abstract Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic voiding disorder that presents with pain in the urinary bladder and surrounding pelvic region. A growing body of evidence suggests that an increase in the permeability of the urothelium, the epithelial barrier that lines the interior of the bladder, contributes to the symptoms of IC/BPS. To examine the consequence of increased urothelial permeability on pelvic pain and afferent excitability, we overexpressed in the urothelium claudin 2 (Cldn2), a tight junction (TJ)-associated protein whose message is significantly upregulated in biopsies of IC/BPS patients. Consistent with the presence of bladder-derived pain, rats overexpressing Cldn2 showed hypersensitivity to von Frey filaments applied to the pelvic region. Overexpression of Cldn2 increased the expression of c-Fos and promoted the activation of ERK1/2 in spinal cord segments receiving bladder input, which we conceive is the result of noxious stimulation of afferent pathways. To determine whether the mechanical allodynia observed in rats with reduced urothelial barrier function results from altered afferent activity, we examined the firing of acutely isolated bladder sensory neurons. In patch-clamp recordings, about 30% of the bladder sensory neurons from rats transduced with Cldn2, but not controls transduced with GFP, displayed spontaneous activity. Furthermore, bladder sensory neurons with tetrodotoxin-sensitive (TTX-S) action potentials from rats transduced with Cldn2 showed hyperexcitability in response to suprathreshold electrical stimulation. These findings suggest that as a result of a leaky urothelium, the diffusion of urinary solutes through the urothelial barrier sensitizes bladders afferents, promoting voiding at low filling volumes and pain. PMID:28560313

  5. New airways for resuscitation?

    Science.gov (United States)

    Cook, T M; Hommers, C

    2006-06-01

    Over the last 15 years supraglottic airway devices (SADs), most notably the classic laryngeal mask airway (LMA) have revolutionised airway management in anaesthesia. In contrast for resuscitation, both in and outside hospital, facemask ventilation and tracheal intubation remain the mainstays of airway management. However there is evidence that both these techniques have complications and are often poorly performed by inexperienced personnel. Tracheal intubation also has the potential to cause serious harm or death through unrecognised oesophageal intubation. SADs may have a role in airway management for resuscitation as first responder devices, rescue devices or for use during patient extraction. In particular they may be beneficial as the level of skill required to use the device safely may be less than for the tracheal tube. Concerns have been expressed over the ability to ventilate the lungs successfully and also the risk of aspiration with SADs. The only SADs recommended by ILCOR in its current guidance are the classic LMA and combitube. Several SADs have recently been introduced with claims that ventilation and airway protection is improved. This pragmatic review examines recent developments in SAD technology and the relevance of this to the potential for using SADs during resuscitation. In addition to examining research directly related to resuscitation both on bench models and in patients the review also examines evidence from anaesthetic practice. SADS discussed include the classic, intubating and Proseal LMAs, the combitube, the laryngeal tube, laryngeal tube sonda mark I and II and single use laryngeal masks.

  6. Airway management in trauma.

    Science.gov (United States)

    Langeron, O; Birenbaum, A; Amour, J

    2009-05-01

    Maintenance of a patent and prevention of aspiration are essential for the management of the trauma patient, that requires experienced physicians in airway control techniques. Difficulties of the airway control in the trauma setting are increased by the vital failures, the risk of aspiration, the potential cervical spine injury, the combative patient, and the obvious risk of difficult tracheal intubation related to specific injury related to the trauma. Endotracheal intubation remains the gold standard in trauma patient airway management and should be performed via the oral route with a rapid sequence induction and a manual in-line stabilization maneuver, to decrease the risks previously mentioned. Different techniques to control the airway in trauma patients are presented: improvement of the laryngoscopic vision, lighted stylet tracheal intubation, retrograde technique for orotracheal intubation, the laryngeal mask and the intubating laryngeal mask airways, the combitube and cricothyroidotomy. Management of the airway in trauma patients requires regular training in these techniques and the knowledge of complementary techniques allowing tracheal intubation or oxygenation to overcome difficult intubation and to prevent major complications as hypoxemia and aspiration.

  7. Heat pulse excitability of vestibular hair cells and afferent neurons

    Science.gov (United States)

    Brichta, Alan M.; Tabatabaee, Hessam; Boutros, Peter J.; Ahn, JoongHo; Della Santina, Charles C.; Poppi, Lauren A.; Lim, Rebecca

    2016-01-01

    In the present study we combined electrophysiology with optical heat pulse stimuli to examine thermodynamics of membrane electrical excitability in mammalian vestibular hair cells and afferent neurons. We recorded whole cell currents in mammalian type II vestibular hair cells using an excised preparation (mouse) and action potentials (APs) in afferent neurons in vivo (chinchilla) in response to optical heat pulses applied to the crista (ΔT ≈ 0.25°C per pulse). Afferent spike trains evoked by heat pulse stimuli were diverse and included asynchronous inhibition, asynchronous excitation, and/or phase-locked APs synchronized to each infrared heat pulse. Thermal responses of membrane currents responsible for APs in ganglion neurons were strictly excitatory, with Q10 ≈ 2. In contrast, hair cells responded with a mix of excitatory and inhibitory currents. Excitatory hair cell membrane currents included a thermoelectric capacitive current proportional to the rate of temperature rise (dT/dt) and an inward conduction current driven by ΔT. An iberiotoxin-sensitive inhibitory conduction current was also evoked by ΔT, rising in heat pulse excitability in vestibular sensory organs and provide quantitative methods for rational application of optical heat pulses to examine protein biophysics and manipulate cellular excitability. PMID:27226448

  8. Heat pulse excitability of vestibular hair cells and afferent neurons.

    Science.gov (United States)

    Rabbitt, Richard D; Brichta, Alan M; Tabatabaee, Hessam; Boutros, Peter J; Ahn, JoongHo; Della Santina, Charles C; Poppi, Lauren A; Lim, Rebecca

    2016-08-01

    In the present study we combined electrophysiology with optical heat pulse stimuli to examine thermodynamics of membrane electrical excitability in mammalian vestibular hair cells and afferent neurons. We recorded whole cell currents in mammalian type II vestibular hair cells using an excised preparation (mouse) and action potentials (APs) in afferent neurons in vivo (chinchilla) in response to optical heat pulses applied to the crista (ΔT ≈ 0.25°C per pulse). Afferent spike trains evoked by heat pulse stimuli were diverse and included asynchronous inhibition, asynchronous excitation, and/or phase-locked APs synchronized to each infrared heat pulse. Thermal responses of membrane currents responsible for APs in ganglion neurons were strictly excitatory, with Q10 ≈ 2. In contrast, hair cells responded with a mix of excitatory and inhibitory currents. Excitatory hair cell membrane currents included a thermoelectric capacitive current proportional to the rate of temperature rise (dT/dt) and an inward conduction current driven by ΔT An iberiotoxin-sensitive inhibitory conduction current was also evoked by ΔT, rising in protein biophysics and manipulate cellular excitability. Copyright © 2016 the American Physiological Society.

  9. Extubation of the difficult airway.

    Science.gov (United States)

    Faris, Khaldoun; Zayaruzny, Maksim; Spanakis, Spiro

    2011-01-01

    Managing the airway in the intensive care unit (ICU) is complicated by a wide array of physiologic factors. Difficult airway may be a consequence of patient’s anatomy or airway edema developed during the ICU stay and mechanical ventilation. The incidence of failed airways and of cardiac arrest related to airway instrumentation in the ICU is much higher than that of elective intubations performed in the operating room. In this article, we will provide a framework for identifying a difficult airway, criteria for safe extubation, as well as review the devices that are available for airway management in the ICU. Proficiency in identifying a potentially difficult airway and thorough familiarity with strategies and techniques of securing the airway are necessary for safe practice of critical care medicine

  10. Tonic aortic depressor nerve stimulation does not impede baroreflex dynamic characteristics concomitantly mediated by the stimulated nerve.

    Science.gov (United States)

    Kawada, Toru; Turner, Michael J; Shimizu, Shuji; Kamiya, Atsunori; Shishido, Toshiaki; Sugimachi, Masaru

    2018-03-01

    Although electrical activation of the carotid sinus baroreflex (baroreflex activation therapy) is being explored as a device therapy for resistant hypertension, possible effects on baroreflex dynamic characteristics of interaction between electrical stimulation and pressure inputs are not fully elucidated. To examine whether the electrical stimulation of the baroreceptor afferent nerve impedes normal short-term arterial pressure (AP) regulation mediated by the stimulated nerve, we electrically stimulated the right aortic depressor nerve (ADN) while estimating the baroreflex dynamic characteristics by imposing pressure inputs to the isolated baroreceptor region of the right ADN in nine anesthetized rats. A Gaussian white noise signal with a mean of 120 mmHg and standard deviation of 20 mmHg was used for the pressure perturbation. A tonic ADN stimulation (2 or 5 Hz, 10 V, 0.1-ms pulse width) decreased mean sympathetic nerve activity (367.0 ± 70.9 vs. 247.3 ± 47.2 arbitrary units, P ADN stimulation did not affect the slope of dynamic gain in the neural arc transfer function from pressure perturbation to sympathetic nerve activity (16.9 ± 1.0 vs. 14.7 ± 1.6 dB/decade, not significant). These results indicate that electrical stimulation of the baroreceptor afferent nerve does not significantly impede the dynamic characteristics of the arterial baroreflex concomitantly mediated by the stimulated nerve. Short-term AP regulation by the arterial baroreflex may be preserved during the baroreflex activation therapy.

  11. Central projections of antennular chemosensory and mechanosensory afferents in the brain of the terrestrial hermit crab (Coenobita clypeatus; Coenobitidae, Anomura)

    Science.gov (United States)

    Tuchina, Oksana; Koczan, Stefan; Harzsch, Steffen; Rybak, Jürgen; Wolff, Gabriella; Strausfeld, Nicholas J.; Hansson, Bill S.

    2015-01-01

    The Coenobitidae (Decapoda, Anomura, Paguroidea) is a taxon of hermit crabs that includes two genera with a fully terrestrial life style as adults. Previous studies have shown that Coenobitidae have evolved a sense of spatial odor localization that is behaviorally highly relevant. Here, we examined the central olfactory pathway of these animals by analyzing central projections of the antennular nerve of Coenobita clypeatus, combining backfilling of the nerve with dextran-coupled dye, Golgi impregnations and three-dimensional reconstruction of the primary olfactory center, the antennular lobe. The principal pattern of putative olfactory sensory afferents in C. clypeatus is in many aspects similar to what have been established for aquatic decapod crustaceans, such as the spiny lobster Panulirus argus. However, there are also obvious differences that may, or may not represent adaptations related to a terrestrial lifestyle. In C. clypeatus, the antennular lobe dominates the deutocerebrum, having more than one thousand allantoid-shaped subunits. We observed two distinct patterns of sensory neuron innervation: putative olfactory afferents from the aesthetascs either supply the cap/subcap region of the subunits or they extend through its full depth. Our data also demonstrate that any one sensory axon can supply input to several subunits. Putative chemosensory (non-aesthetasc) and mechanosensory axons represent a different pathway and innervate the lateral and median antennular neuropils. Hence, we suggest that the chemosensory input in C. clypeatus might be represented via a dual pathway: aesthetascs target the antennular lobe, and bimodal sensilla target the lateral antennular neuropil and median antennular neuropil. The present data is compared to related findings in other decapod crustaceans. PMID:26236202

  12. Central projections of antennular chemosensory and mechanosensory afferents in the brain of the terrestrial hermit crab (Coenobita clypeatus; Coenobitidae, Anomura).

    Science.gov (United States)

    Tuchina, Oksana; Koczan, Stefan; Harzsch, Steffen; Rybak, Jürgen; Wolff, Gabriella; Strausfeld, Nicholas J; Hansson, Bill S

    2015-01-01

    The Coenobitidae (Decapoda, Anomura, Paguroidea) is a taxon of hermit crabs that includes two genera with a fully terrestrial life style as adults. Previous studies have shown that Coenobitidae have evolved a sense of spatial odor localization that is behaviorally highly relevant. Here, we examined the central olfactory pathway of these animals by analyzing central projections of the antennular nerve of Coenobita clypeatus, combining backfilling of the nerve with dextran-coupled dye, Golgi impregnations and three-dimensional reconstruction of the primary olfactory center, the antennular lobe. The principal pattern of putative olfactory sensory afferents in C. clypeatus is in many aspects similar to what have been established for aquatic decapod crustaceans, such as the spiny lobster Panulirus argus. However, there are also obvious differences that may, or may not represent adaptations related to a terrestrial lifestyle. In C. clypeatus, the antennular lobe dominates the deutocerebrum, having more than one thousand allantoid-shaped subunits. We observed two distinct patterns of sensory neuron innervation: putative olfactory afferents from the aesthetascs either supply the cap/subcap region of the subunits or they extend through its full depth. Our data also demonstrate that any one sensory axon can supply input to several subunits. Putative chemosensory (non-aesthetasc) and mechanosensory axons represent a different pathway and innervate the lateral and median antennular neuropils. Hence, we suggest that the chemosensory input in C. clypeatus might be represented via a dual pathway: aesthetascs target the antennular lobe, and bimodal sensilla target the lateral antennular neuropil and median antennular neuropil. The present data is compared to related findings in other decapod crustaceans.

  13. Central projections of antennular chemosensory and mechanosensory afferents in the brain of the terrestrial hermit crab (Coenobita clypeatus; Coenobitidae, Anomura

    Directory of Open Access Journals (Sweden)

    Oksana eTuchina

    2015-07-01

    Full Text Available The Coenobitidae (Decapoda, Anomura, Paguroidea is a taxon of hermit crabs that includes two genera with a fully terrestrial life style as adults. Previous studies have shown that Coenobitidae have evolved a sense of spatial odor localization that is behaviorally highly relevant. Here, we examined the central olfactory pathway of these animals by analyzing central projections of the antennular nerve of Coenobita clypeatus, combining backfilling of the nerve with dextran-coupled dye, Golgi impregnations and three-dimensional reconstruction of the primary olfactory center, the antennular lobe. The principal pattern of putative olfactory sensory afferents in C. clypeatus is in many aspects similar to what have been established for aquatic decapod crustaceans, such as the spiny lobster Panulirus argus. However, there are also obvious differences that may, or may not represent adaptations related to a terrestrial lifestyle. In C. clypeatus, the antennular lobe dominates the deutocerebrum, having more than one thousand allantoid-shaped subunits. We observed two distinct patterns of sensory neuron innervation: putative olfactory afferents from the aesthetascs either supply the cap/subcap region of the subunits or they extend through its full depth. Our data also demonstrate that any one sensory axon can supply input to several subunits. Putative chemosensory (non-aesthetasc and mechanosensory axons represent a different pathway and innervate the lateral and median antennular neuropils. Hence, we suggest that the chemosensory input in C. clypeatus might be represented via a dual pathway: aesthetascs target the antennular lobe, and bimodal sensilla target the lateral antennular neuropil and median antennular neuropil. The present data is compared to related findings in other decapod crustaceans.

  14. Integrated care pathways for airway diseases (AIRWAYS-ICPs)

    NARCIS (Netherlands)

    Bousquet, J.; Addis, A.; Adcock, I.; Agache, I.; Agusti, A.; Alonso, A.; Annesi-Maesano, I.; Anto, J. M.; Bachert, C.; Baena-Cagnani, C. E.; Bai, C.; Baigenzhin, A.; Barbara, C.; Barnes, P. J.; Bateman, E. D.; Beck, L.; Bedbrook, A.; Bel, E. H.; Benezet, O.; Bennoor, K. S.; Benson, M.; Bernabeu-Wittel, M.; Bewick, M.; Bindslev-Jensen, C.; Blain, H.; Blasi, F.; Bonini, M.; Bonini, S.; Boulet, L. P.; Bourdin, A.; Bourret, R.; Bousquet, P. J.; Brightling, C. E.; Briggs, A.; Brozek, J.; Buh, R.; Bush, A.; Caimmi, D.; Calderon, M.; Calverley, P.; Camargos, P. A.; Camuzat, T.; Canonica, G. W.; Carlsen, K. H.; Casale, T. B.; Cazzola, M.; Sarabia, A. M. Cepeda; Cesario, A.; Chen, Y. Z.; Chkhartishvili, E.; Chavannes, N. H.; Chiron, R.; Chuchalin, A.; Chung, K. F.; Cox, L.; Crooks, G.; Crooks, M. G.; Cruz, A. A.; Custovic, A.; Dahl, R.; Dahlen, S. E.; De Blay, F.; Dedeu, T.; Deleanu, D.; Demoly, P.; Devillier, P.; Didier, A.; Dinh-Xuan, A. T.; Djukanovic, R.; Dokic, D.; Douagui, H.; Dubakiene, R.; Eglin, S.; Elliot, F.; Emuzyte, R.; Fabbri, L.; Wagner, A. Fink; Fletcher, M.; Fokkens, W. J.; Fonseca, J.; Franco, A.; Frith, P.; Furber, A.; Gaga, M.; Garces, J.; Garcia-Aymerich, J.; Gamkrelidze, A.; Gonzales-Diaz, S.; Gouzi, F.; Guzman, M. A.; Haahtela, T.; Harrison, D.; Hayot, M.; Heaney, L. G.; Heinrich, J.; Hellings, P. W.; Hooper, J.; Humbert, M.; Hyland, M.; Iaccarino, G.; Jakovenko, D.; Jardim, J. R.; Jeandel, C.; Jenkins, C.; Johnston, S. L.; Jonquet, O.; Joos, G.; Jung, K. S.; Kalayci, O.; Karunanithi, S.; Keil, T.; Khaltaev, N.; Kolek, V.; Kowalski, M. L.; Kull, I.; Kuna, P.; Kvedariene, V.; Le, L. T.; Carlsen, K. C. Lodrup; Louis, R.; MacNee, W.; Mair, A.; Majer, I.; Manning, P.; Keenoy, E. de Manuel; Masjedi, M. R.; Meten, E.; Melo-Gomes, E.; Menzies-Gow, A.; Mercier, G.; Mercier, J.; Michel, J. P.; Miculinic, N.; Mihaltan, F.; Milenkovic, B.; Molimard, M.; Mamas, I.; Montilla-Santana, A.; Morais-Almeida, M.; Morgan, M.; N'Diaye, M.; Nafti, S.; Nekam, K.; Neou, A.; Nicod, L.; O'Hehir, R.; Ohta, K.; Paggiaro, P.; Palkonen, S.; Palmer, S.; Papadopoulos, N. G.; Papi, A.; Passalacqua, G.; Pavord, I.; Pigearias, B.; Plavec, D.; Postma, D. S.; Price, D.; Rabe, K. F.; Pontal, F. Radier; Redon, J.; Rennard, S.; Roberts, J.; Robine, J. M.; Roca, J.; Roche, N.; Rodenas, F.; Roggeri, A.; Rolland, C.; Rosado-Pinto, J.; Ryan, D.; Samolinski, B.; Sanchez-Borges, M.; Schunemann, H. J.; Sheikh, A.; Shields, M.; Siafakas, N.; Sibille, Y.; Similowski, T.; Small, I.; Sola-Morales, O.; Sooronbaev, T.; Stelmach, R.; Sterk, P. J.; Stiris, T.; Sud, P.; Tellier, V.; To, T.; Todo-Bom, A.; Triggiani, M.; Valenta, R.; Valero, A. L.; Valiulis, A.; Valovirta, E.; Van Ganse, E.; Vandenplas, O.; Vasankari, T.; Vestbo, J.; Vezzani, G.; Viegi, G.; Visier, L.; Vogelmeier, C.; Vontetsianos, T.; Wagstaff, R.; Wahn, U.; Wallaert, B.; Whalley, B.; Wickman, M.; Williams, D. M.; Wilson, N.; Yawn, B. P.; Yiallouros, P. K.; Yorgancioglu, A.; Yusuf, O. M.; Zar, H. J.; Zhong, N.; Zidarn, M.; Zuberbier, T.

    The objective of Integrated Care Pathways for Airway Diseases (AIRWAYS-ICPs) is to launch a collaboration to develop multi-sectoral care pathways for chronic respiratory diseases in European countries and regions. AIRWAYS-ICPs has strategic relevance to the European Union Health Strategy and will

  15. Integrated care pathways for airway diseases (AIRWAYS-ICPs)

    NARCIS (Netherlands)

    Bousquet, J.; Addis, A.; Adcock, I.; Agache, I.; Agusti, A.; Alonso, A.; Annesi-Maesano, I.; Anto, J. M.; Bachert, C.; Baena-Cagnani, C. E.; Bai, C.; Baigenzhin, A.; Barbara, C.; Barnes, P. J.; Bateman, E. D.; Beck, L.; Bedbrook, A.; Bel, E. H.; Benezet, O.; Bennoor, K. S.; Benson, M.; Bernabeu-Wittel, M.; Bewick, M.; Bindslev-Jensen, C.; Blain, H.; Blasi, F.; Bonini, M.; Bonini, S.; Boulet, L. P.; Bourdin, A.; Bourret, R.; Bousquet, P. J.; Brightling, C. E.; Briggs, A.; Brozek, J.; Buhl, R.; Bush, A.; Caimmi, D.; Calderon, M.; Calverley, P.; Camargos, P. A.; Camuzat, T.; Canonica, G. W.; Carlsen, K. H.; Casale, T. B.; Cazzola, M.; Cepeda Sarabia, A. M.; Cesario, A.; Chen, Y. Z.; Chkhartishvili, E.; Chavannes, N. H.; Chiron, R.; Chuchalin, A.; Chung, K. F.; Cox, L.; Crooks, G.; Crooks, M. G.; Cruz, A. A.; Custovic, A.; Dahl, R.; Dahlen, S. E.; de Blay, F.; Dedeu, T.; Deleanu, D.; Demoly, P.; Devillier, P.; Didier, A.; Dinh-Xuan, A. T.; Djukanovic, R.; Dokic, D.; Douagui, H.; Dubakiene, R.; Eglin, S.; Elliot, F.; Emuzyte, R.; Fabbri, L.; Fink Wagner, A.; Fletcher, M.; Fokkens, W. J.; Fonseca, J.; Franco, A.; Frith, P.; Furber, A.; Gaga, M.; Garcés, J.; Garcia-Aymerich, J.; Gamkrelidze, A.; Gonzales-Diaz, S.; Gouzi, F.; Guzmán, M. A.; Haahtela, T.; Harrison, D.; Hayot, M.; Heaney, L. G.; Heinrich, J.; Hellings, P. W.; Hooper, J.; Humbert, M.; Hyland, M.; Iaccarino, G.; Jakovenko, D.; Jardim, J. R.; Jeandel, C.; Jenkins, C.; Johnston, S. L.; Jonquet, O.; Joos, G.; Jung, K. S.; Kalayci, O.; Karunanithi, S.; Keil, T.; Khaltaev, N.; Kolek, V.; Kowalski, M. L.; Kull, I.; Kuna, P.; Kvedariene, V.; Le, L. T.; Lodrup Carlsen, K. C.; Louis, R.; MacNee, W.; Mair, A.; Majer, I.; Manning, P.; de Manuel Keenoy, E.; Masjedi, M. R.; Melen, E.; Melo-Gomes, E.; Menzies-Gow, A.; Mercier, G.; Mercier, J.; Michel, J. P.; Miculinic, N.; Mihaltan, F.; Milenkovic, B.; Molimard, M.; Momas, I.; Montilla-Santana, A.; Morais-Almeida, M.; Morgan, M.; N'Diaye, M.; Nafti, S.; Nekam, K.; Neou, A.; Nicod, L.; O'Hehir, R.; Ohta, K.; Paggiaro, P.; Palkonen, S.; Palmer, S.; Papadopoulos, N. G.; Papi, A.; Passalacqua, G.; Pavord, I.; Pigearias, B.; Plavec, D.; Postma, D. S.; Price, D.; Rabe, K. F.; Radier Pontal, F.; Redon, J.; Rennard, S.; Roberts, J.; Robine, J. M.; Roca, J.; Roche, N.; Rodenas, F.; Roggeri, A.; Rolland, C.; Rosado-Pinto, J.; Ryan, D.; Samolinski, B.; Sanchez-Borges, M.; Schünemann, H. J.; Sheikh, A.; Shields, M.; Siafakas, N.; Sibille, Y.; Similowski, T.; Small, I.; Sola-Morales, O.; Sooronbaev, T.; Stelmach, R.; Sterk, P. J.; Stiris, T.; Sud, P.; Tellier, V.; To, T.; Todo-Bom, A.; Triggiani, M.; Valenta, R.; Valero, A. L.; Valiulis, A.; Valovirta, E.; van Ganse, E.; Vandenplas, O.; Vasankari, T.; Vestbo, J.; Vezzani, G.; Viegi, G.; Visier, L.; Vogelmeier, C.; Vontetsianos, T.; Wagstaff, R.; Wahn, U.; Wallaert, B.; Whalley, B.; Wickman, M.; Williams, D. M.; Wilson, N.; Yawn, B. P.; Yiallouros, P. K.; Yorgancioglu, A.; Yusuf, O. M.; Zar, H. J.; Zhong, N.; Zidarn, M.; Zuberbier, T.

    2014-01-01

    The objective of Integrated Care Pathways for Airway Diseases (AIRWAYS-ICPs) is to launch a collaboration to develop multi-sectoral care pathways for chronic respiratory diseases in European countries and regions. AIRWAYS-ICPs has strategic relevance to the European Union Health Strategy and will

  16. Parkinson disease affects peripheral sensory nerves in the pharynx.

    Science.gov (United States)

    Mu, Liancai; Sobotka, Stanislaw; Chen, Jingming; Su, Hungxi; Sanders, Ira; Nyirenda, Themba; Adler, Charles H; Shill, Holly A; Caviness, John N; Samanta, Johan E; Sue, Lucia I; Beach, Thomas G

    2013-07-01

    Dysphagia is very common in patients with Parkinson disease (PD) and often leads to aspiration pneumonia, the most common cause of death in PD. Current therapies are largely ineffective for dysphagia. Because pharyngeal sensation normally triggers the swallowing reflex, we examined pharyngeal sensory nerves in PD patients for Lewy pathology.Sensory nerves supplying the pharynx were excised from autopsied pharynges obtained from patients with clinically diagnosed and neuropathologically confirmed PD (n = 10) and healthy age-matched controls (n = 4). We examined the glossopharyngeal nerve (cranial nerve IX), the pharyngeal sensory branch of the vagus nerve (PSB-X), and the internal superior laryngeal nerve (ISLN) innervating the laryngopharynx. Immunohistochemistry for phosphorylated α-synuclein was used to detect Lewy pathology. Axonal α-synuclein aggregates in the pharyngeal sensory nerves were identified in all of the PD subjects but not in the controls. The density of α-synuclein-positive lesions was greater in PD patients with dysphagia versus those without dysphagia. In addition, α-synuclein-immunoreactive nerve fibers in the ISLN were much more abundant than those in cranial nerve IX and PSB-X. These findings suggest that pharyngeal sensory nerves are directly affected by pathologic processes in PD. These abnormalities may decrease pharyngeal sensation, thereby impairing swallowing and airway protective reflexes and contributing to dysphagia and aspiration.

  17. Equine recurrent airway obstruction

    Directory of Open Access Journals (Sweden)

    Artur Niedźwiedź

    2014-10-01

    Full Text Available Equine Recurrent Airway Obstruction (RAO, also known as heaves or broken wind, is one of the most common disease in middle-aged horses. Inflammation of the airway is inducted by organic dust exposure. This disease is characterized by neutrophilic inflammation, bronchospasm, excessive mucus production and pathologic changes in the bronchiolar walls. Clinical signs are resolved in 3-4 weeks after environmental changes. Horses suffering from RAO are susceptible to allergens throughout their lives, therefore they should be properly managed. In therapy the most importanthing is to eliminate dustexposure, administration of corticosteroids and use bronchodilators to improve pulmonary function.

  18. Advanced Pediatric Airway Simulation.

    Science.gov (United States)

    Myer, Charles M; Jabbour, Noel

    2017-10-01

    Simulation is an emerging and viable means to increase pediatric airway surgical training. A variety of simulators currently exist that may be used or modified for laryngoscopy, bronchoscopy, and endoscopic intervention, although anatomic realism and utility for complex procedures are limited. There is a need for further development of improved endoscopic and anatomic models. Innovative techniques are enabling small-scale manufacturing of generalizable and patient-specific simulators. The high acuity of the pediatric airway patient makes the use of simulation an attractive modality for training, competency maintenance, and patient safety quality-improvement studies. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Bladder afferent hyperexcitability in bladder pain syndrome/interstitial cystitis.

    Science.gov (United States)

    Yoshimura, Naoki; Oguchi, Tomohiko; Yokoyama, Hitoshi; Funahashi, Yasuhito; Yoshikawa, Satoru; Sugino, Yoshio; Kawamorita, Naoki; Kashyap, Mahendra P; Chancellor, Michael B; Tyagi, Pradeep; Ogawa, Teruyuki

    2014-04-01

    Bladder pain syndrome/interstitial cystitis is a disease with lower urinary tract symptoms, such as bladder pain and urinary frequency, which results in seriously impaired quality of life of patients. The extreme pain and urinary frequency are often difficult to treat. Although the etiology of bladder pain syndrome/interstitial cystitis is still not known, there is increasing evidence showing that afferent hyperexcitability as a result of neurogenic bladder inflammation and urothelial dysfunction is important to the pathophysiological basis of symptom development. Further investigation of the pathophysiology will lead to the effective treatment of patients with bladder pain syndrome/interstitial cystitis. © 2014 The Japanese Urological Association.

  20. Chloride regulates afferent arteriolar contraction in response to depolarization

    DEFF Research Database (Denmark)

    Hansen, P B; Jensen, B L; Skott, O

    1998-01-01

    afferent arterioles. In 70% of vessels examined, K+-induced contraction was abolished by acute substitution of bath chloride. Consecutive addition of Cl- (30, 60, 80, 100, 110, and 117 mmol/L) restored the sensitivity to K+, and half-maximal response was observed at 82 mmol/L chloride. The calcium channel...... antagonist diltiazem (10(-6) mol/L) abolished K+-induced contractions. Bicarbonate did not modify the sensitivity to chloride. Norepinephrine (10(-6) mol/L) induced full contraction in depolarized vessels even in the absence of chloride. Iodide and nitrate were substituted for chloride with no inhibitory...

  1. MR features of a case of afferent loop syndrome presenting as obstructive jaundice

    International Nuclear Information System (INIS)

    Chevallier, P.; Souci, J.; Oddo, F.; Diaine, B.; Padovani, B.; Gueyffier, C.

    2001-01-01

    The afferent loop syndrome corresponds to an acute or chronic obstruction of the afferent loop following a partial gastrectomy with Billroth II gastro-jejunal anastomosis. We describe the case of a 77-year-old man with history of partial gastrectomy for peptic ulcer disease performed 31 years ago and currently admitted for jaundice and poor general status. MR imaging showed dilatation of biliary and pancreatic ducts and showed a soft tissue mass between the afferent loop and the residual stomach. Endoscopy showed complete obstruction of the afferent loop by a biopsy-proven adenocarcinoma. The patient died of sepsis shortly after endoscopy of septicemia. (authors)

  2. Sympathetic modulation of muscle spindle afferent sensitivity to stretch in rabbit jaw closing muscles.

    Science.gov (United States)

    Roatta, S; Windhorst, U; Ljubisavljevic, M; Johansson, H; Passatore, M

    2002-04-01

    Previous reports showed that sympathetic stimulation affects the activity of muscle spindle afferents (MSAs). The aim of the present work is to study the characteristics of sympathetic modulation of MSA response to stretch: (i) on the dynamic and static components of the stretch response, and (ii) on group Ia and II MSAs to evaluate potentially different effects. In anaesthetised rabbits, the peripheral stump of the cervical sympathetic nerve (CSN) was stimulated at 10 impulses s(-1) for 45-90 s. The responses of single MSAs to trapezoidal displacement of the mandible were recorded from the mesencephalic trigeminal nucleus. The following characteristic parameters were determined from averaged trapezoidal responses: initial frequency (IF), peak frequency at the end of the ramp (PF), and static index (SI). From these, other parameters were derived: dynamic index (DI = PF - SI), dynamic difference (DD = PF - IF) and static difference (SD = SI - IF). The effects of CSN stimulation were also evaluated during changes in the state of intrafusal muscle fibre contraction induced by succinylcholine and curare. In a population of 124 MSAs, 106 units (85.4 %) were affected by sympathetic stimulation. In general, while changes in resting discharge varied among different units (Ia vs. II) and experimental conditions (curarised vs. non-curarised), ranging from enhancement to strong depression of firing, the amplitude of the response to muscle stretches consistently decreased. This was confirmed and detailed in a quantitative analysis performed on 49 muscle spindle afferents. In both the non-curarised (23 units) and curarised (26 units) condition, stimulation of the CSN reduced the response amplitude in terms of DD and SD, but hardly affected DI. The effects were equally present in both Ia and II units; they were shown to be independent from gamma drive and intrafusal muscle tone and not secondary to muscle hypoxia. Sympathetic action on the resting discharge (IF) was less

  3. Coronary responses to cold air inhalation following afferent and efferent blockade

    Science.gov (United States)

    Gao, Zhaohui; McQuillan, Patrick M.; Leuenberger, Urs A.; Sinoway, Lawrence I.

    2014-01-01

    Cardiac ischemia and angina pectoris are commonly experienced during exertion in a cold environment. In the current study we tested the hypotheses that oropharyngeal afferent blockade (i.e., local anesthesia of the upper airway with lidocaine) as well as systemic β-adrenergic receptor blockade (i.e., intravenous propranolol) would improve the balance between myocardial oxygen supply and demand in response to the combined stimulus of cold air inhalation (−15 to −30°C) and isometric handgrip exercise (Cold + Grip). Young healthy subjects underwent Cold + Grip following lidocaine, propranolol, and control (no drug). Heart rate, blood pressure, and coronary blood flow velocity (CBV, from Doppler echocardiography) were continuously measured. Rate-pressure product (RPP) was calculated, and changes from baseline were compared between treatments. The change in RPP at the end of Cold + Grip was not different between lidocaine (2,441 ± 376) and control conditions (3,159 ± 626); CBV responses were also not different between treatments. With propranolol, heart rate (8 ± 1 vs. 14 ± 3 beats/min) and RPP responses to Cold + Grip were significantly attenuated. However, at peak exercise propranolol also resulted in a smaller ΔCBV (1.4 ± 0.8 vs. 5.3 ± 1.4 cm/s, P = 0.035), such that the relationship between coronary flow and cardiac metabolism was impaired under propranolol (0.43 ± 0.37 vs. 2.1 ± 0.63 arbitrary units). These data suggest that cold air breathing and isometric exercise significantly influence efferent control of coronary blood flow. Additionally, β-adrenergic vasodilation may play a significant role in coronary regulation during exercise. PMID:24816257

  4. Neurons in the nucleus of the solitary tract mediating inputs from emetic vagal afferents and the area postrema to the pattern generator for the emetic act in dogs.

    Science.gov (United States)

    Koga, T; Fukuda, H

    1992-08-01

    Roles of neurons in the nucleus of the solitary tract corresponding to the area subpostrema (mNST) for the retching reflex were investigated in decerebrate, paralyzed dogs. Retching was defined as rhythmic coactivation of the phrenic and abdominal muscle nerves. Retching which had been induced by stimulation of the left and right abdominal vagus nerves was impaired by cooling the left and right mNSTs, respectively. This result indicates that the mNST neurons mediate activities of emetic vagal afferents. All 40 non-respiratory neurons in the mNST, which had excitatory response to pulse train stimulation of the vagus nerve, were also activated by continuous stimulation of the vagus nerve to provoke retching. During provoked retching, however, these neurons did not exhibit any activities modulated in association with retching. The average latency of responses of these neurons to the pulse train stimulation (306.5 ms) was significantly shorter than that of the inspiratory neurons in the lateral NST and the adjacent reticular formation. Discharge frequencies of these neurons in the mNST gradually increased after administration of apomorphine (6/10) and glutamate (14/14) to the 4th ventricle. Antidromic responses to stimulation of the Bötzinger complex were observed in some (20/289) of the mNST neurons. These findings suggest that neurons in the mNST mediate the information from both the abdominal vagal afferents and the area postrema and drive the pattern generator for retching and vomiting, which is assumed to be located in the Bötzinger complex.

  5. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... NACFC Carolyn and C Richard Mattingly Leadership in Mental Health Care Award Mary M. Kontos Award NACFC Reflections ... help your infant or child manage their lung health, watch parents of children with CF and a respiratory therapist talk about the different techniques they use for airway clearance. ... Instagram Email Find a Clinical Trial Help us blaze ...

  6. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... center. Carrier Testing for Cystic Fibrosis CFTR-Related Metabolic Syndrome (CRMS) How Babies Are Screened in IRT-Only ... Nutrition in Children and Adults Clinical Care Guidelines Nutrition in Pediatrics Clinical ... Airway Clearance Therapies Clinical Care Guidelines Chronic Medications to Maintain Lung ...

  7. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Leaders About Us News Blog Chapters ... different ways to clear your airways. Most are easy to do. Infants and toddlers will need help from a parent or caregiver. Older kids and adults can choose ACTs that they can ...

  8. Upper airway evaluation

    International Nuclear Information System (INIS)

    Hoffman, E.A.; Gefter, W.B.; Schnall, M.; Nordberg, J.; Listerud, J.; Lenkinski, R.E.

    1988-01-01

    The authors are evaluating upper-airway sleep disorders with magnetic resonance (MR) imaging and x-ray cine computed tomography (CT). Fixed structural anatomy is visualized with multisection spin-echo MR imaging, the dynamic component with cine CT. Unique aspects of the study are described in this paper

  9. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... and Their Families When There's More Than One Person With CF in the Same School Daily Life ... Awards and Grants Career Development Awards Research Awards Training Awards CF ... Clearance Airway Clearance Techniques (ACTs) There are different ways to clear your ...

  10. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... be taken through a nebulizer during ACTs. Inhaled antibiotics should be taken after ACTs are finished and the lungs are as clear of mucus as possible. This will allow the medication to reach deeply into the smaller airways to attack bacteria. Choose What's Best for You Your respiratory therapist ...

  11. Obstetric airway management

    African Journals Online (AJOL)

    face mask. There were 66 cases of aspiration (0.15%) and two mortalities. Both of the mortalities occurred secondary to solid food aspiration. Mendelson correctly identified delayed gastric emptying in the labouring patient, coupled with the loss of airway reflexes during general anaesthesia, as contributory factors to the ...

  12. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Team Your cystic fibrosis care team includes a group of CF health care professionals who partner with ... Awards and Grants Career Development Awards Research Awards Training Awards CF ... Clearance Airway Clearance Techniques (ACTs) There are different ways to clear your ...

  13. Positive airway pressure treatment

    Science.gov (United States)

    ... and depression and a better mood Normal sleep patterns Lower blood pressure (in people with high blood pressure) Your health care provider will prescribe the type of PAP machine that ... patterns. Bilevel positive airway pressure (BiPAP or BIPAP) has ...

  14. Cross-Modal Calibration of Vestibular Afference for Human Balance.

    Science.gov (United States)

    Héroux, Martin E; Law, Tammy C Y; Fitzpatrick, Richard C; Blouin, Jean-Sébastien

    2015-01-01

    To determine how the vestibular sense controls balance, we used instantaneous head angular velocity to drive a galvanic vestibular stimulus so that afference would signal that head movement was faster or slower than actual. In effect, this changed vestibular afferent gain. This increased sway 4-fold when subjects (N = 8) stood without vision. However, after a 240 s conditioning period with stable balance achieved through reliable visual or somatosensory cues, sway returned to normal. An equivalent galvanic stimulus unrelated to sway (not driven by head motion) was equally destabilising but in this situation the conditioning period of stable balance did not reduce sway. Reflex muscle responses evoked by an independent, higher bandwidth vestibular stimulus were initially reduced in amplitude by the galvanic stimulus but returned to normal levels after the conditioning period, contrary to predictions that they would decrease after adaptation to increased sensory gain and increase after adaptation to decreased sensory gain. We conclude that an erroneous vestibular signal of head motion during standing has profound effects on balance control. If it is unrelated to current head motion, the CNS has no immediate mechanism of ignoring the vestibular signal to reduce its influence on destabilising balance. This result is inconsistent with sensory reweighting based on disturbances. The increase in sway with increased sensory gain is also inconsistent with a simple feedback model of vestibular reflex action. Thus, we propose that recalibration of a forward sensory model best explains the reinterpretation of an altered reafferent signal of head motion during stable balance.

  15. Interactions between visceral afferent signaling and stimulus processing

    Directory of Open Access Journals (Sweden)

    Hugo D Critchley

    2015-08-01

    Full Text Available Visceral afferent signals to the brain influence thoughts, feelings and behaviour. Here we highlight the findings of a set of empirical investigations in humans concerning body-mind interaction that focus on how feedback from states of autonomic arousal shapes cognition and emotion. There is a longstanding debate regarding the contribution of the body, to mental processes. Recent theoretical models broadly acknowledge the role of (autonomically-mediated physiological arousal to emotional, social and motivational behaviours, yet the underlying mechanisms are only partially characterized. Neuroimaging is overcoming this shortfall; first, by demonstrating correlations between autonomic change and discrete patterns of evoked, and task-independent, neural activity; second, by mapping the central consequences of clinical perturbations in autonomic response and; third, by probing how dynamic fluctuations in peripheral autonomic state are integrated with perceptual, cognitive and emotional processes. Building on the notion that an important source of the brain’s representation of physiological arousal is derived from afferent information from arterial baroreceptors, we have exploited the phasic nature of these signals to show their differential contribution to the processing of emotionally-salient stimuli. This recent work highlights the facilitation at neural and behavioral levels of fear and threat processing that contrasts with the more established observations of the inhibition of central pain processing during baroreceptors activation. The implications of this body-brain-mind axis are discussed.

  16. Extraglottic airway devices: technology update

    Directory of Open Access Journals (Sweden)

    Sharma B

    2017-08-01

    Full Text Available Bimla Sharma, Chand Sahai, Jayashree Sood Department of Anaesthesiology, Pain and Perioperative Medicine, Sir Ganga Ram Hospital, New Delhi, India Abstract: Extraglottic airway devices (EADs have revolutionized the field of airway management. The invention of the laryngeal mask airway was a game changer, and since then, there have been several innovations to improve the EADs in design, functionality, safety and construction material. These have ranged from changes in the shape of the mask, number of cuffs and material used, like rubber, polyvinylchloride and latex. Phthalates, which were added to the construction material in order to increase device flexibility, were later omitted when this chemical was found to have serious adverse reproductive outcomes. The various designs brought out by numerous companies manufacturing EADs resulted in the addition of several devices to the airway market. These airway devices were put to use, many of them with inadequate or no evidence base regarding their efficacy and safety. To reduce the possibility of compromising the safety of the patient, the Difficult Airway Society (DAS formed the Airway Device Evaluation Project Team (ADEPT to strengthen the evidence base for airway equipment and vet the new extraglottic devices. A preuse careful analysis of the design and structure may help in better understanding of the functionality of a particular device. In the meantime, the search for the ideal EAD continues. Keywords: extraglottic airway devices, laryngeal mask airway, other extraglottic airway devices, safety, technology update

  17. Electrophysiological study in the infraorbital nerve of the rat: Spontaneous and evoked activity

    Energy Technology Data Exchange (ETDEWEB)

    AlbarracIn, A L [Catedra de Neurociencias, Facultad de Medicina, Universidad Nacional de Tucuman, Av. Roca 2200, PC 4000 (Argentina); Farfan, F D [Departamento de BioingenierIa, FACET, Universidad Nacional de Tucuman, INSIBIO - CONICET, CC 327, PC 4000 (Argentina); Felice, C J [Departamento de BioingenierIa, FACET, Universidad Nacional de Tucuman, INSIBIO - CONICET, CC 327, PC 4000 (Argentina)

    2007-11-15

    In this work we present some studies in the afferent nerve of the rat vibrissae. Studies on spontaneous activity (SA) in this sensorial system are of long data. Nevertheless, SA recordings in the nerve of a single vibrissa have not been made until present. In this work, we use an algorithm based on signal decomposition with Continuous Wavelet Transform (CWT) to analyse the discharges of two nerves. The action potentials of both nerves were detected and the firing rates were calculated. These results suggest that the firing rate of one vibrissa innervation is low considering that this nerve contains hundred of fibers. In addition, we present preliminary studies suggesting important effects of the hair shaft length in the afferent discharge during the vibrissae movements. The experiments consisted in recording the nerve activity after the vibrissae were sectioned at two different levels. The results showed important differences in the signal energy contents. It suggests that the hair shaft length would produce a differential activation of the mechanoreceptors located in the vibrissae follicle.

  18. Electrophysiologic studies of cutaneous nerves of the thoracic limb of the dog.

    Science.gov (United States)

    Kitchell, R L; Whalen, L R; Bailey, C S; Lohse, C L

    1980-01-01

    The cutaneous innervation of the thoracic limb was investigated in 36 barbiturate-anesthetized dogs, using electrophysiologic techniques. The cutaneous area (CA) innervated by each cutaneous nerve was delineated in at least five dogs by stroking the hair in the area with a small watercolor brush while recording from the nerve. Mapping of adjacent CA revealed areas of considerable overlapping. The part of the CA of a given nerve supplied by only that nerve is referred to as its autonomous zone. Of all nerves arising from the brachial plexus, only the suprascapular, subscapular, lateral thoracic, thoracodorsal, and cranial and caudal pectoral nerves lacked cutaneous afferents. The dorsal cutaneous branch of C6 had a CA, but no grossly demonstrable dorsal cutaneous branches for C7 C8, or T1 were found. The cervical nerves had ventral cutaneous branches, but no lateral cutaneous branches. Thoracic nerves T2-T4 had dorsal, ventral, and lateral cutaneous branches. The cutaneous branches of the brachiocephalic, axillary, musculocutaneous, radial, median, and ulnar nerves all had CA which were overlapped by adjacent CA, thus their autonomous zones were much smaller than the cutaneous areas usually depicted for these nerves in anatomy and neurology textbooks.

  19. Development of fusimotor innervation correlates with group Ia afferents but is independent of neurotrophin-3

    NARCIS (Netherlands)

    Ringstedt, T; Copray, S; Walro, J; Kucera, J

    1998-01-01

    Fusimotor neurons, group Ia afferents and muscle spindles are absent in mutant mice lacking the gene for neurotrophin-3 (NT3). To partition the effect of Ia afferent or spindle absence from that of NT3 deprivation on fusimotor neuron development, we examined the fusimotor system in a mutant mouse

  20. Conduction velocity compensation for afferent fiber length in the trunk lateral line of the trout

    NARCIS (Netherlands)

    Schellart, N. A. M.; Kroese, A. B. A.

    2002-01-01

    The trout lateral line contains about 122 trunk scales and is tens of centimeters long. The difference in time of arrival in the hindbrain of simultaneously elicited afferent responses from the neuromasts is unknown. Propagation times of single-fiber afferent responses to water motion revealed that

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

    Science.gov (United States)

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

    2008-10-01

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

  2. Tuning of spinal networks to frequency components of spike trains in individual afferents.

    Science.gov (United States)

    Koerber, H R; Seymour, A W; Mendell, L M

    1991-10-01

    Cord dorsum potentials (CDPs) evoked by primary afferent fiber stimulation reflect the response of postsynaptic dorsal horn neurons. The properties of these CDPs have been shown to vary in accordance with the type of primary afferent fiber stimulated. The purpose of the present study was to determine the relationships between frequency modulation of the afferent input trains, the amplitude modulation of the evoked CDPs, and the type of primary afferent stimulated. The somata of individual primary afferent fibers were impaled in the L7 dorsal root ganglion of alpha-chloralose-anesthetized cats. Action potentials (APs) were evoked in single identified afferents via the intracellular microelectrode while simultaneously recording the response of dorsal horn neurons as CDPs, or activity of individual target interneurons recorded extracellularly or intracellularly. APs were evoked in afferents using temporal patterns identical to the responses of selected afferents to natural stimulation of their receptive fields. Two such physiologically realistic trains, one recorded from a hair follicle and the other from a slowly adapting type 1 receptor, were chosen as standard test trains. Modulation of CDP amplitude in response to this frequency-modulated afferent activity varied according to the type of peripheral mechanoreceptor innervated. Dorsal horn networks driven by A beta afferents innervating hair follicles, rapidly adapting pad (Krause end bulb), and field receptors seemed "tuned" to amplify the onset of activity in single afferents. Networks driven by afferents innervating down hair follicles and pacinian corpuscles required more high-frequency activity to elicit their peak response. Dorsal horn networks driven by afferents innervating slowly adapting receptors including high-threshold mechanoreceptors exhibited some sensitivity to the instantaneous frequency, but in general they reproduced the activity in the afferent fiber much more faithfully. Responses of

  3. Biomarkers in Airway Diseases

    Directory of Open Access Journals (Sweden)

    Janice M Leung

    2013-01-01

    Full Text Available The inherent limitations of spirometry and clinical history have prompted clinicians and scientists to search for surrogate markers of airway diseases. Although few biomarkers have been widely accepted into the clinical armamentarium, the authors explore three sources of biomarkers that have shown promise as indicators of disease severity and treatment response. In asthma, exhaled nitric oxide measurements can predict steroid responsiveness and sputum eosinophil counts have been used to titrate anti-inflammatory therapies. In chronic obstructive pulmonary disease, inflammatory plasma biomarkers, such as fibrinogen, club cell secretory protein-16 and surfactant protein D, can denote greater severity and predict the risk of exacerbations. While the multitude of disease phenotypes in respiratory medicine make biomarker development especially challenging, these three may soon play key roles in the diagnosis and management of airway diseases.

  4. Lipids in airway secretions

    International Nuclear Information System (INIS)

    Bhaskar, K.R.; DeFeudis O'Sullivan, D.; Opaskar-Hincman, H.; Reid, L.M.

    1987-01-01

    Lipids form a significant portion of airway mucus yet they have not received the same attention that epithelial glycoproteins have. We have analysed, by thin layer chromatography, lipids present in airway mucus under 'normal' and hypersecretory (pathological) conditions.The 'normals' included (1) bronchial lavage obtained from healthy human volunteers and from dogs and (2) secretions produced ''in vitro'' by human (bronchial) and canine (tracheal) explants. Hypersecretory mucus samples included (1) lavage from dogs made bronchitic by exposure to SO 2 , (2) bronchial aspirates from acute and chronic tracheostomy patients, (3) sputum from patients with cystic fibrosis and chronic bronchitis and (4) postmortem secretions from patients who died from sudden infant death syndrome (SIDS) or from status asthmaticus. Cholesterol was found to be the predominant lipid in 'normal' mucus with lesser amounts of phospholipids. No glycolipids were detected. In the hypersecretory mucus, in addition to neutral and phospholipids, glycolipids were present in appreciable amounts, often the predominant species, suggesting that these may be useful as markers of disease. Radioactive precursors 14 C acetate and 14 C palmitate were incorporated into lipids secreted ''in vitro'' by canine tracheal explants indicating that they are synthesised by the airway. (author)

  5. H-REFLEX UP-CONDITIONING ENCOURAGES RECOVERY OF EMG ACTIVITY AND H-REFLEXES AFTER SCIATIC NERVE TRANSECTION AND REPAIR IN RATS

    OpenAIRE

    Chen, Yi; Wang, Yu; Chen, Lu; Sun, Chenyuo; English, Arthur W.; Wolpaw, Jonathan R.; Chen, Xiang Yang

    2010-01-01

    Operant conditioning of the spinal stretch reflex or its electrical analog, the H-reflex, produces spinal cord plasticity and can thereby affect motoneuron responses to primary afferent input. To explore whether this conditioning can affect the functional outcome after peripheral nerve injury, we assessed the effect of up-conditioning soleus (SOL) H-reflex on SOL and tibialis anterior (TA) function after sciatic nerve transection and repair. Sprague-Dawley rats were implanted with EMG electro...

  6. Effects of levodropropizine on vagal afferent C-fibres in the cat.

    Science.gov (United States)

    Shams, H; Daffonchio, L; Scheid, P

    1996-03-01

    1. Levodropropizine (LVDP) is an effective antitussive drug. Its effects on single-unit discharge of vagal afferent C-fibres were tested in anaesthetized cats to assess whether an inhibition of vagal C-fibres is involved in its antitussive properties. Vagal C-fibres, identified by their response to phenylbiguanide (PBG), were recorded via suction electrodes from the distal part of the cut vagus. Based on their response to lung inflation, C-fibres were classified as pulmonary (19 fibres) or non-pulmonary (6 fibres). 2. PBG increased the discharge rate of both C-fibre types and activated a respiratory reflex causing apnoea. This reflex was abolished when the second vagus nerve was cut as well, while PBG-mediated stimulation of the C-fibres was not affected by vagotomy. 3. LVDP was administered intravenously and the C-fibre response to PBG was compared with that before administration of the drug. LVDP reduced both the duration of apnoea and the response of the C-fibre to PBG. 4. Comparison of the C-fibre responses to PBG and to a mixture of PBG and LVDP revealed that the period of apnoea was shortened and the discharge rate of the C-fibre reduced when LVDP was present. 5. The LVDP-induced inhibition of the C-fibre response to PBG was on average 50% in pulmonary and 25% in non-pulmonary fibres. 6. These results suggest that LVDP significantly reduces the response of vagal C-fibres to chemical stimuli. It is, thus, likely that the antitussive effect of LVDP is mediated through its inhibitory action on C-fibres.

  7. Intermedin in the paraventricular nucleus attenuates cardiac sympathetic afferent reflex in chronic heart failure rats.

    Directory of Open Access Journals (Sweden)

    Xian-Bing Gan

    Full Text Available BACKGROUND AND AIM: Intermedin (IMD is a member of calcitonin/calcitonin gene-related peptide (CGRP family together with adrenomedullin (AM and amylin. It has a wide distribution in the central nervous system (CNS especially in hypothalamic paraventricular nucleus (PVN. Cardiac sympathetic afferent reflex (CSAR is enhanced in chronic heart failure (CHF rats. The aim of this study is to determine the effect of IMD in the PVN on CSAR and its related mechanisms in CHF rats. METHODOLOGY/PRINCIPAL FINDINGS: Rats were subjected to left descending coronary artery ligation to induce CHF or sham-operation (Sham. Renal sympathetic nerve activity (RSNA, mean arterial pressure (MAP and heart rate (HR were recorded. CSAR was evaluated by the RSNA and MAP responses to epicardial application of capsaicin. Acute experiments were carried out 8 weeks after coronary ligation or sham surgery under anesthesia. IMD and angiotensin II (Ang II levels in the PVN were up-regulated in CHF rats. Bilateral PVN microinjection of IMD caused greater decreases in CSAR and the baseline RSNA and MAP in CHF rats than those in Sham rats. The decrease of CSAR caused by IMD was prevented by pretreatment with AM receptor antagonist AM22-52, but not CGRP receptor antagonist CGRP8-37. Ang II in the PVN significantly enhanced CSAR and superoxide anions level, which was inhibited by PVN pretreatment with IMD or tempol (a superoxide anions scavenger in Sham and CHF rats. CONCLUSION: IMD in the PVN inhibits CSAR via AM receptor, and attenuates the effects of Ang II on CSAR and superoxide anions level in CHF rats. PVN superoxide anions involve in the effect of IMD on attenuating Ang II-induced CSAR response.

  8. Superoxide anions in paraventricular nucleus modulate adipose afferent reflex and sympathetic activity in rats.

    Directory of Open Access Journals (Sweden)

    Lei Ding

    Full Text Available Adipose afferent reflex (AAR is a sympatho-excitatory reflex induced by chemical stimulation of white adipose tissue (WAT. Ionotropic glutamate receptors including NMDA receptors (NMDAR and non-NMDA receptors (non-NMDAR in paraventricular nucleus (PVN mediate the AAR. Enhanced AAR contributes to sympathetic activation and hypertension in obesity rats. This study was designed to investigate the role and mechanism of superoxide anions in PVN in modulating the AAR.Renal sympathetic nerve activity (RSNA and mean arterial pressure (MAP were recorded in anesthetized rats. AAR was evaluated by the RSNA and MAP responses to injections of capsaicin into four sites of right inguinal WAT (8.0 nmol in 8.0 µl for each site. Microinjection of polyethylene glycol-superoxide dismutase (PEG-SOD, the superoxide anion scavenger tempol or the NAD(PH oxidase inhibitor apocynin into the PVN decreased the baseline RSNA and MAP, and attenuated the AAR. Unilateral WAT injection of capsaicin increased superoxide anions in bilateral PVN, which was prevented by the WAT denervation. WAT injection of capsaicin increased superoxide anion level and NAD(PH oxidase activity in the PVN, which was abolished by the PVN pretreatment with the combined NMDAR antagonist AP5 and non-NMDAR antagonist CNQX. Microinjection of the NMDAR agonist NMDA or the non-NMDAR agonist AMPA increased superoxide anion level and NAD(PH oxidase activity in the PVN.NAD(PH oxidase-derived superoxide anions in the PVN contributes to the tonic modulation of AAR. Activation of ionotropic glutamate receptors in the PVN is involved in the AAR-induced production of superoxide anions in the PVN.

  9. Causes of the difficult airway.

    Science.gov (United States)

    Orfanos, John G; Quereshy, Faisal A

    2010-03-01

    Recognizing a potentially difficult airway is important in avoiding a life-threatening emergency. There are 2 separate scenarios for considering the difficult airway: difficult mask ventilation (DMV) and difficult tracheal intubation (DTI). DMV can be described as lacking the ability to maintain oxygen saturation or lacking the ability to reverse signs of inadequate ventilation with positive-pressure mask ventilation under general anesthesia. DTI remains constant among anesthesia-related patient injuries, and is the third most common respiratory-related episode leading to death and possible brain damage. It is important to preoperatively assess every patient by completing a full history and physical. A thorough history can provide clues in detecting a possible difficult airway. Airway impairment has been further subdivided into the anatomic regions that affect the airway, namely above the larynx, supraglottic, glottic, subglottic, and tracheobronchial. This article discusses the factors that can result in a difficult airway. Copyright 2010. Published by Elsevier Inc.

  10. Anticholinergic treatment in airways diseases.

    LENUS (Irish Health Repository)

    Flynn, Robert A

    2009-10-01

    The prevalence of chronic airways diseases such as chronic obstructive pulmonary disease and asthma is increasing. They lead to symptoms such as a cough and shortness of breath, partially through bronchoconstriction. Inhaled anticholinergics are one of a number of treatments designed to treat bronchoconstriction in airways disease. Both short-acting and long-acting agents are now available and this review highlights their efficacy and adverse event profile in chronic airways diseases.

  11. Differential roles of galanin on mechanical and cooling responses at the primary afferent nociceptor

    Directory of Open Access Journals (Sweden)

    Hulse Richard P

    2012-06-01

    Full Text Available Abstract Background Galanin is expressed in a small percentage of intact small diameter sensory neurons of the dorsal root ganglia and in the afferent terminals of the superficial lamina of the dorsal horn of the spinal cord. The neuropeptide modulates nociception demonstrating dose-dependent pro- and anti-nociceptive actions in the naïve animal. Galanin also plays an important role in chronic pain, with the anti-nociceptive actions enhanced in rodent neuropathic pain models. In this study we compared the role played by galanin and its receptors in mechanical and cold allodynia by identifying individual rat C-fibre nociceptors and characterising their responses to mechanical or acetone stimulation. Results Mechanically evoked responses in C-fibre nociceptors from naive rats were sensitised after close intra-arterial infusion of galanin or Gal2-11 (a galanin receptor-2/3 agonist confirming previous data that galanin modulates nociception via activation of GalR2. In contrast, the same dose and route of administration of galanin, but not Gal2-11, inhibited acetone and menthol cooling evoked responses, demonstrating that this inhibitory mechanism is not mediated by activation of GalR2. We then used the partial saphenous nerve ligation injury model of neuropathic pain (PSNI and the complete Freund’s adjuvant model of inflammation in the rat and demonstrated that close intra-arterial infusion of galanin, but not Gal2-11, reduced cooling evoked nociceptor activity and cooling allodynia in both paradigms, whilst galanin and Gal2-11 both decreased mechanical activation thresholds. A previously described transgenic mouse line which inducibly over-expresses galanin (Gal-OE after nerve injury was then used to investigate whether manipulating the levels of endogenous galanin also modulates cooling evoked nociceptive behaviours after PSNI. Acetone withdrawal behaviours in naive mice showed no differences between Gal-OE and wildtype (WT mice. 7-days after

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

    Science.gov (United States)

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

    2010-03-01

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

  13. Microstimulation of primary afferent neurons in the L7 dorsal root ganglia using multielectrode arrays in anesthetized cats: thresholds and recruitment properties

    Science.gov (United States)

    Gaunt, R. A.; Hokanson, J. A.; Weber, D. J.

    2009-10-01

    Current research in motor neural prosthetics has focused primarily on issues related to the extraction of motor command signals from the brain (e.g. brain-machine interfaces) to direct the motion of prosthetic limbs. Patients using these types of systems could benefit from a somatosensory neural interface that conveys natural tactile and kinesthetic sensations for the prosthesis. Electrical microstimulation within the dorsal root ganglia (DRG) has been proposed as one method to accomplish this, yet little is known about the recruitment properties of electrical microstimulation in activating nerve fibers in this structure. Current-controlled microstimulation pulses in the range of 1-15 µA (200 µs, leading cathodic pulse) were delivered to the L7 DRG in four anesthetized cats using penetrating microelectrode arrays. Evoked responses and their corresponding conduction velocities (CVs) were measured in the sciatic nerve with a 5-pole nerve cuff electrode arranged as two adjacent tripoles. It was found that in 76% of the 69 electrodes tested, the stimulus threshold was less than or equal to 3 µA, with the lowest recorded threshold being 1.1 µA. The CVs of afferents recruited at threshold had a bimodal distribution with peaks at 70 m s-1 and 85 m s-1. In 53% of cases, the CV of the response at threshold was slower (i.e. smaller diameter fiber) than the CVs of responses observed at increasing stimulation amplitudes. In summary, we found that microstimulation applied through penetrating microelectrodes in the DRG provides selective recruitment of afferent fibers from a range of sensory modalities (as identified by CVs) at very low stimulation intensities. We conclude that the DRG may serve as an attractive location from which to introduce surrogate somatosensory feedback into the nervous system.

  14. Transient receptor potential ankyrin 1 channel localized to non-neuronal airway cells promotes non-neurogenic inflammation

    DEFF Research Database (Denmark)

    Nassini, Romina; Pedretti, Pamela; Moretto, Nadia

    2012-01-01

    and fibroblasts, acrolein and CS extract evoked IL-8 release, a response selectively reduced by TRPA1 antagonists. Capsaicin, agonist of the transient receptor potential vanilloid 1 (TRPV1), a channel co-expressed with TRPA1 by airway sensory nerves, and acrolein or CS (TRPA1 agonists), or the neuropeptide...... substance P (SP), which is released from sensory nerve terminals by capsaicin, acrolein or CS), produced neurogenic inflammation in mouse airways. However, only acrolein and CS, but not capsaicin or SP, released the keratinocyte chemoattractant (CXCL-1/KC, IL-8 analogue) in bronchoalveolar lavage (BAL...

  15. Azithromycin ameliorates airway remodeling via inhibiting airway epithelium apoptosis.

    Science.gov (United States)

    Liu, Yuanqi; Pu, Yue; Li, Diandian; Zhou, Liming; Wan, Lihong

    2017-02-01

    Azithromycin can benefit treating allergic airway inflammation and remodeling. In the present study, we hypothesized that azithromycin alleviated airway epithelium injury through inhibiting airway epithelium apoptosis via down regulation of caspase-3 and Bax/Bcl2 ratio in vivo and in vitro. Ovalbumin induced rat asthma model and TGF-β1-induced BEAS-2B cell apoptosis model were established, respectively. In vivo experiments, airway epithelium was stained with hematoxylin and eosin (HE) and periodic acid-Schiff (PAS) to histologically evaluate the airway inflammation and remodeling. Airway epithelium apoptotic index (AI) was further analyzed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), while expression of apoptosis related gene (Bax, Bcl2, Caspase-3) in lungs were measured by qRT-PCR and western blotting, respectively. In vitro experiments, apoptosis were evaluated by Flow cytometry (FCM) and TUNEL. Above apoptosis related gene were also measured by qRT-PCR and western blotting. Compared with the OVA group, azithromycin significantly reduced the inflammation score, peribronchial smooth muscle layer thickness, epithelial thickening and goblet cell metaplasia (Pazithromycin-treated rats (Pazithromycin significantly suppressed TGF-β1-induced BEAS-2B cells apoptosis (PAzithromycin is an attractive treatment option for reducing airway epithelial cell apoptosis by improving the imbalance of Bax/Bcl-2 ratio and inhibiting Caspase-3 level in airway epithelium. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. The Laryngeal Mask Airway (LMA) as an alternative to airway ...

    African Journals Online (AJOL)

    Background: To evaluate the possibility of airway management using a laryngeal mask airway (LMA) during dental procedures on mentally retarded (MR) patients and patients with genetic diseases. Design: A prospective pilot study. Setting: University Hospital. Methods: A pilot study was designed to induce general ...

  17. Optic Nerve Injury in a Patient with Chronic Allergic Conjunctivitis

    Directory of Open Access Journals (Sweden)

    Ribhi Hazin

    2014-01-01

    Full Text Available Manipulation of the optic nerve can lead to irreversible vision changes. We present a patient with a past medical history of skin allergy and allergic conjunctivitis (AC who presented with insidious unexplained unilateral vision loss. Physical exam revealed significant blepharospasm, mild lid edema, bulbar conjunctival hyperemia, afferent pupillary defect, and slight papillary hypertrophy. Slit lamp examination demonstrated superior and inferior conjunctival scarring as well as superior corneal scarring but no signs of external trauma or neurological damage were noted. Conjunctival cultures and cytologic evaluation demonstrated significant eosinophilic infiltration. Subsequent ophthalmoscopic examination revealed optic nerve atrophy. Upon further questioning, the patient admitted to vigorous itching of the affected eye for many months. Given the presenting symptoms, history, and negative ophthalmological workup, it was determined that the optic nerve atrophy was likely secondary to digital pressure from vigorous itching. Although AC can be a significant source of decreased vision via corneal ulceration, no reported cases have ever described AC-induced vision loss of this degree from vigorous itching and chronic pressure leading to optic nerve damage. Despite being self-limiting in nature, allergic conjunctivitis should be properly managed as extreme cases can result in mechanical compression of the optic nerve and compromise vision.

  18. Incidence of unanticipated difficult airway using an objective airway score versus a standard clinical airway assessment

    DEFF Research Database (Denmark)

    Nørskov, Anders Kehlet; Rosenstock, Charlotte Valentin; Wetterslev, Jørn

    2013-01-01

    -specific assessment. Data from patients' pre-operative airway assessment are registered in the Danish Anaesthesia Database. Objective scores for intubation and mask ventilation grade the severity of airway managements. The accuracy of predicting difficult intubation and mask ventilation is measured for each group...... the examination and registration of predictors for difficult mask ventilation with a non-specified clinical airway assessment on prediction of difficult mask ventilation.Method/Design: We cluster-randomized 28 Danish departments of anaesthesia to airway assessment either by the SARI or by usual non...... that registration of the SARI and predictors for difficult mask ventilation are mandatory for the intervention group but invisible to controls....

  19. Regulation of the renal sympathetic nerves in heart failure

    Directory of Open Access Journals (Sweden)

    Rohit eRamchandra

    2015-08-01

    Full Text Available Heart failure (HF is a serious debilitating condition with poor survival rates and an increasing level of prevalence. Heart failure is associated with an increase in renal norepinephrine spillover, which is an independent predictor of mortality in HF patients. The excessive sympatho-excitation that is a hallmark of heart failure has long-term effects that contribute to disease progression. An increase in directly recorded renal sympathetic nerve activity has also been recorded in animal models of heart failure. This review will focus on the mechanisms controlling sympathetic nerve activity to the kidney during normal conditions and alterations in these mechanisms during heart failure. In particular the roles of afferent reflexes and central mechanisms will be discussed.

  20. Rhinosinusitis and the lower airways

    NARCIS (Netherlands)

    Hellings, Peter W.; Hens, Greet

    2009-01-01

    The interaction between upper and lower airway disease has been recognized for centuries, with recent studies showing a direct link between upper and airway inflammation in allergic patients. The mechanisms underlying the interaction between nasal and bronchial inflammation have primarily been

  1. Nerve Injuries in Athletes.

    Science.gov (United States)

    Collins, Kathryn; And Others

    1988-01-01

    Over a two-year period this study evaluated the condition of 65 athletes with nerve injuries. These injuries represent the spectrum of nerve injuries likely to be encountered in sports medicine clinics. (Author/MT)

  2. Allergic Fungal Airway Disease.

    Science.gov (United States)

    Rick, E M; Woolnough, K; Pashley, C H; Wardlaw, A J

    Fungi are ubiquitous and form their own kingdom. Up to 80 genera of fungi have been linked to type I allergic disease, and yet, commercial reagents to test for sensitization are available for relatively few species. In terms of asthma, it is important to distinguish between species unable to grow at body temperature and those that can (thermotolerant) and thereby have the potential to colonize the respiratory tract. The former, which include the commonly studied Alternaria and Cladosporium genera, can act as aeroallergens whose clinical effects are predictably related to exposure levels. In contrast, thermotolerant species, which include fungi from the Candida, Aspergillus, and Penicillium genera, can cause a persistent allergenic stimulus independent of their airborne concentrations. Moreover, their ability to germinate in the airways provides a more diverse allergenic stimulus, and may result in noninvasive infection, which enhances inflammation. The close association between IgE sensitization to thermotolerant filamentous fungi and fixed airflow obstruction, bronchiectasis, and lung fibrosis suggests a much more tissue-damaging process than that seen with aeroallergens. This review provides an overview of fungal allergens and the patterns of clinical disease associated with exposure. It clarifies the various terminologies associated with fungal allergy in asthma and makes the case for a new term (allergic fungal airway disease) to include all people with asthma at risk of developing lung damage as a result of their fungal allergy. Lastly, it discusses the management of fungirelated asthma.

  3. Optic Nerve Pit

    Science.gov (United States)

    ... Conditions Frequently Asked Questions Español Condiciones Chinese Conditions Optic Nerve Pit What is optic nerve pit? An optic nerve pit is a ... may be seen in both eyes. How is optic pit diagnosed? If the pit is not affecting ...

  4. Computed tomographic features of afferent loop syndrome: pictorial essay

    Energy Technology Data Exchange (ETDEWEB)

    Zissin, R. [Tel-Aviv Univ., Dept. of Diagnostic Imaging, Sapir Medical Center, Kfar Saba, Sackler Faculty of Medicine, Tel Aviv (Israel); Hertz, M. [Tel-Aviv Univ., Dept. of Diagnostic Imaging, Chaim Sheba Medical Center, Tel Hashomer, Tel Aviv (Israel); Paran, H. [Tel-Aviv Univ., Dept. of Diagnostic Imaging, Surgery ' A' , Sapir Medical Center, Kfar Saba, Sackler Faculty of Medicine, Tel Aviv (Israel); Osadchy, A. [Tel-Aviv Univ., Dept. of Diagnostic Imaging, Sapir Medical Center, Kfar Saba, Sackler Faculty of Medicine, Tel Aviv (Israel); Gayer, G. [Tel-Aviv Univ., Dept. of Diagnostic Imaging, Assaf Harofe Medical Center, Zrifin, Sackler Faculty of Medicine, Tel Aviv (Israel)

    2005-04-15

    This pictorial essay reviews the computed tomography (CT) findings of afferent loop syndrome (ALS) in various pathological conditions to demonstrate the contribution of a common imaging modality-that is, abdominal CT, used nowadays for various abdominal complaints-to the diagnosis of ALS. ALS is caused by obstruction of the duodenum and jejunum proximal to a gastrojejunostomy anastomosis. It is a rare complication after Billroth II subtotal gastrectomy and even more rare after total or subtotal gastrectomy with Roux-en-Y reconstruction. Although currently advanced medical treatment and endoscopic interventions have dramatically decreased the necessity of surgery for peptic ulcer disease, ALS may appear years after previously common operations. Alternatively, the use of surgical resection for early gastric cancer nowadays leads to an increasing rate of malignancy-related ALS. Clinically, ALS may be difficult to diagnose as its presentation may be vague and nonspecific, but it has a characteristic appearance on CT. Clinicians and radiologists should therefore be familiar with this rare complication. Prompt recognition and correct diagnosis of this syndrome and its probable etiology are important as a guide for treatment. This review illustrates the CT features of ALS in various conditions. (author)

  5. Evaluation of afferent pain pathways in adrenomyeloneuropathic patients.

    Science.gov (United States)

    Yagüe, Sara; Veciana, Misericordia; Casasnovas, Carlos; Ruiz, Montserrat; Pedro, Jordi; Valls-Solé, Josep; Pujol, Aurora

    2018-03-01

    Patients with adrenomyeloneuropathy may have dysfunctions of visual, auditory, motor and somatosensory pathways. We thought on examining the nociceptive pathways by means of laser evoked potentials (LEPs), to obtain additional information on the pathophysiology of this condition. In 13 adrenomyeloneuropathic patients we examined LEPs to leg, arm and face stimulation. Normative data were obtained from 10 healthy subjects examined in the same experimental conditions. We also examined brainstem auditory evoked potentials (BAEPs), pattern reversal full-field visual evoked potentials (VEPs), motor evoked potentials (MEPs) and somatosensory evoked potentials (SEPs). Upper and lower limb MEPs and SEPs, as well as BAEPs, were abnormal in all patients, while VEPs were abnormal in 3 of them (23.1%). LEPs revealed abnormalities to stimulation of the face in 4 patients (30.7%), the forearm in 4 patients (30.7%) and the leg in 10 patients (76.9%). The pathologic process of adrenomyeloneuropathy is characterized by a preferential involvement of auditory, motor and somatosensory tracts and less severely of the visual and nociceptive pathways. This non-inflammatory distal axonopathy preferably damages large myelinated spinal tracts but there is also partial involvement of small myelinated fibres. LEPs studies can provide relevant information about afferent pain pathways involvement in adrenomyeloneuropathic patients. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  6. An interventional airway delivery service for congenital high airway obstruction.

    Science.gov (United States)

    Yaneza, M M C; Cameron, A; Clement, W A; Fairgrieve, R; Ledingham, M A; Morrissey, M S; Simpson, J; Wynne, D M; Kubba, H

    2015-08-01

    Congenital airway obstruction is rare but potentially fatal. We developed a complex airways interventional delivery team to manage such cases. Antenatal imaging detects airway compromise at an early stage and facilitates the planning of delivery procedures ('ex utero intrapartum treatment' and 'operation on placental support') which maintain feto-placental circulation whilst an airway is secured. A retrospective review was performed of cases in which ENT input was required at birth for airway obstruction. Four neonates were delivered before implementation of the service: two were intubated and another two underwent tracheostomy but died in the peri-natal period. Seven neonates were delivered after implementation of the service: six were intubated and one underwent immediate tracheostomy. Five subsequently underwent tracheostomy (three have since been decannulated). One child with multiple congenital anomalies died due to respiratory failure. Airway obstruction was caused by lymphatic malformation, teratoma, costo-craniomandibular syndrome and choristoma. In the absence of other anomalies, interventional airway delivery led to reduced mortality and improved outcomes.

  7. Neuronal thresholds and choice-related activity of otolith afferent fibers during heading perception.

    Science.gov (United States)

    Yu, Xiong-jie; Dickman, J David; DeAngelis, Gregory C; Angelaki, Dora E

    2015-05-19

    How activity of sensory neurons leads to perceptual decisions remains a challenge to understand. Correlations between choices and single neuron firing rates have been found early in vestibular processing, in the brainstem and cerebellum. To investigate the origins of choice-related activity, we have recorded from otolith afferent fibers while animals performed a fine heading discrimination task. We find that afferent fibers have similar discrimination thresholds as central cells, and the most sensitive fibers have thresholds that are only twofold or threefold greater than perceptual thresholds. Unlike brainstem and cerebellar nuclei neurons, spike counts from afferent fibers do not exhibit trial-by-trial correlations with perceptual decisions. This finding may reflect the fact that otolith afferent responses are poorly suited for driving heading perception because they fail to discriminate self-motion from changes in orientation relative to gravity. Alternatively, if choice probabilities reflect top-down inference signals, they are not relayed to the vestibular periphery.

  8. Organization of diencephalic and brainstem afferent projections to the lateral septum in the rat

    NARCIS (Netherlands)

    Luiten, Paul G.M.; Kuipers, Folkert; Schuitmaker, Hans

    1982-01-01

    Ascending diencephalic and brainstem afferents to the lateral septal column were studied by retrograde transport of horseradish peroxidase following microiontophoretic injections in the various subdivisions of the lateral septal area. Predominantly ispilateral cells, of which several coincide with

  9. Degeneration of capsaicin sensitive sensory nerves enhances myocardial injury in acute myocardial infarction in rats.

    Science.gov (United States)

    Zhang, Rui-Lin; Guo, Zheng; Wang, Li-Li; Wu, Jie

    2012-09-20

    Evidence indicated an involvement of afferent nerves in the pathology of acute myocardial infarction. This study was undertaken to clarify the role and mechanisms by which the sensory afferent degeneration exacerbates the myocardial injury in acute myocardial infarction in rats. The myocardial injury was assessed by analysis of 1) the differences in the infarct size, myocyte apoptosis, the caspase activity in the myocardium and cardiac troponin I in serum between the denervated and non-denervated rats; 2) the differences in the size of infarctiom with and without antagonisms of endogenous neurokinin 1 receptor or calcitonin gene related peptide receptor in acute myocardial infarction. Degeneration of the afferent nerves resulted in marked increase in the pain threshold and decrease in substance P and calcitonin gene related peptide in dorsal root ganglia, spinal dorsal horn and myocardium. Increases of the infarction size (39% ± 4% vs. 26% ± 4%,), troponin-I (28.4 ± 8.89 ng/ml, vs. 14.6 ± 9.75 ng/ml), apoptosis of myocytes (by 1.8 ± 0.2 folds) and caspase-3 activity (1.6 ± 0.3 vs. 1.05 ± 0.18) were observed in the denervated animals at 6h of myocardial infarction, compared with the non-denervated rats. Antagonisms of the endogenous neurokinin 1 receptor or calcitonin gene related peptide receptor caused increase of the size of infarction in the animals. Degeneration of capsaicin sensitive afferent nerves enhances the myocardial injury of acute myocardial infarction, possibly due to reduction of endogenous calcitonin gene related peptide and substance P. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  10. Tempol Prevents Altered K+ Channel Regulation of Afferent Arteriolar Tone in Diabetic Rat Kidney

    Science.gov (United States)

    Troncoso Brindeiro, Carmen M.; Lane, Pascale H.; Carmines, Pamela K.

    2012-01-01

    Experiments were performed to test the hypothesis that oxidative stress underlies the enhanced tonic dilator impact of inward-rectifier K+ (KIR) channels on renal afferent arterioles of rats with streptozotocin-induced diabetes. Sham and diabetic rats were left untreated or provided tempol in their drinking water for 26±1 days, after which afferent arteriolar lumen diameter and its responsiveness to K+ channel blockade were measured using the in vitro blood-perfused juxtamedullary nephron technique. Afferent diameter averaged 19.4±0.8 μm in sham rats and 24.4±0.8 μm in diabetic rats (Ptempol treatment prevented diabetes-induced increases in both renal vascular dihydroethidium staining and baseline afferent arteriolar diameter. Moreover, tempol prevented the exaggeration of afferent arteriolar responses to Ba2+, tertiapin-Q, and glibenclamide otherwise evident in diabetic rats. Preglomerular microvascular smooth muscle cells expressed mRNA encoding Kir1.1, Kir2.1 and Kir6.1. Neither diabetes nor tempol altered Kir1.1, Kir2.1, Kir6.1 or SUR2B protein levels in renal cortical microvessels. To the extent that the effects of tempol reflect its antioxidant actions, our observations indicate that oxidative stress contributes to the exaggerated impact of Kir1.1, Kir2.1 and KATP channels on afferent arteriolar tone during diabetes and that this phenomenon involves post-translational modulation of channel function. PMID:22252401

  11. The 'initial burst' of human primary muscle spindle afferents has at least two components.

    Science.gov (United States)

    Edin, B B

    1991-10-01

    Ten muscle spindle primary afferents from the extensor digitorum communis muscle of man were studied with single unit afferent recordings. Responses to slow test stretches with three different pre-history conditions were assessed to investigate the contribution of rapid stretches to the stretch sensitization phenomenon. In two of the conditions, the slow test ramps were preceded by rapid stretch after which the parent muscle of the receptor was either (a) kept short for 5 seconds or (b) kept long for 3.2 seconds and then returned to the short muscle length for 5 seconds. The third condition (c) consisted of a slow stretch from short to long muscle length followed by a rapid return to the short muscle length, in turn followed by 5 seconds at the short muscle length. Afferent responses were depressed when the muscle had been kept at the long length after the rapid stretches (condition b) and enhanced when the muscle had been kept at the short length (conditions a & c). A prominent 'initial burst' was only present in the afferent discharge when the parent muscles of the primary endings had been kept short (condition a). A second, more prolonged burst was present for conditions (a) and (c) but was lacking or inconspicuous when the muscle had been kept long after rapid stretches (condition b). The rapid stretches in the stretch sensitization paradigm appear to be a primary factor not only for the enhanced responses of sensitized primary afferents but also for the depressed responses of desensitized primary afferents.

  12. Descending facilitation from the rostral ventromedial medulla maintains nerve injury-induced central sensitization.

    Science.gov (United States)

    Vera-Portocarrero, L P; Zhang, E-T; Ossipov, M H; Xie, J Y; King, T; Lai, J; Porreca, F

    2006-07-21

    Nerve injury can produce hypersensitivity to noxious and normally innocuous stimulation. Injury-induced central (i.e. spinal) sensitization is thought to arise from enhanced afferent input to the spinal cord and to be critical for expression of behavioral hypersensitivity. Descending facilitatory influences from the rostral ventromedial medulla have been suggested to also be critical for the maintenance, though not the initiation, of experimental neuropathic pain. The possibility that descending facilitation from the rostral ventromedial medulla is required for the maintenance of central sensitization was examined by determining whether ablation of mu-opioid receptor-expressing cells within the rostral ventromedial medulla prevented the enhanced expression of repetitive touch-evoked FOS within the spinal cord of animals with spinal nerve ligation injury as well as nerve injury-induced behavioral hypersensitivity. Rats received a single microinjection of vehicle, saporin, dermorphin or dermorphin-saporin into the rostral ventromedial medulla and 28 days later, underwent either sham or spinal nerve ligation procedures. Animals receiving rostral ventromedial medulla pretreatment with vehicle, dermorphin or saporin that were subjected to spinal nerve ligation demonstrated both thermal and tactile hypersensitivity, and showed significantly increased expression of touch-evoked FOS in the dorsal horn ipsilateral to nerve injury compared with sham-operated controls at days 3, 5 or 10 post-spinal nerve ligation. In contrast, nerve-injured animals pretreated with dermorphin-saporin showed enhanced behaviors and touch-evoked FOS expression in the spinal dorsal horn at day 3, but not days 5 and 10, post-spinal nerve ligation when compared with sham-operated controls. These results indicate the presence of nerve injury-induced behavioral hypersensitivity associated with nerve injury-induced central sensitization. Further, the results demonstrate the novel concept that once

  13. Airway necrosis after salvage esophagectomy

    International Nuclear Information System (INIS)

    Tanaka, Norimitsu; Hokamura, Nobukazu; Tachimori, Yuji

    2010-01-01

    Salvage esophagectomy is the sole curative intent treatment for patients with persistent or recurrent locoregional disease after definitive chemoradiotherapy (CRT) for esophageal carcinoma. However, salvage esophagectomy is a very high-risk operation, and airway necrosis is a fatal complication. Between 1997 and 2007, 49 patients with thoracic esophageal cancer underwent salvage esophagectomy after definitive CRT. We retrospectively compared patients with and without airway necrosis, and investigated operative procedures related to airway necrosis. Airway necrosis occurred in five patients (10.2%), of four patients (80%) died during their hospitalization. Airway necrosis seemed to be closely related to operative procedures, such as resection of bronchial artery and cervical and subcarinal lymph node dissection. Bronchogastric fistula following necrosis of gastric conduit occured in 2 patients reconstructed through posterior mediastinal route. Airway necrosis is a highly lethal complication after salvage esophagectomy. It is important in salvage esophagectomy to take airway blood supply into consideration sufficiently and to reconstruct through retrosternal route to prevent bronchogastric fistula. (author)

  14. Optic nerve oxygenation

    DEFF Research Database (Denmark)

    Stefánsson, Einar; Pedersen, Daniella Bach; Jensen, Peter Koch

    2005-01-01

    The oxygen tension of the optic nerve is regulated by the intraocular pressure and systemic blood pressure, the resistance in the blood vessels and oxygen consumption of the tissue. The oxygen tension is autoregulated and moderate changes in intraocular pressure or blood pressure do not affect...... the optic nerve oxygen tension. If the intraocular pressure is increased above 40 mmHg or the ocular perfusion pressure decreased below 50 mmHg the autoregulation is overwhelmed and the optic nerve becomes hypoxic. A disturbance in oxidative metabolism in the cytochromes of the optic nerve can be seen...... at similar levels of perfusion pressure. The levels of perfusion pressure that lead to optic nerve hypoxia in the laboratory correspond remarkably well to the levels that increase the risk of glaucomatous optic nerve atrophy in human glaucoma patients. The risk for progressive optic nerve atrophy in human...

  15. Optic nerve oxygenation

    DEFF Research Database (Denmark)

    Stefánsson, Einar; Pedersen, Daniella Bach; Jensen, Peter Koch

    2005-01-01

    at similar levels of perfusion pressure. The levels of perfusion pressure that lead to optic nerve hypoxia in the laboratory correspond remarkably well to the levels that increase the risk of glaucomatous optic nerve atrophy in human glaucoma patients. The risk for progressive optic nerve atrophy in human...... glaucoma patients is six times higher at a perfusion pressure of 30 mmHg, which corresponds to a level where the optic nerve is hypoxic in experimental animals, as compared to perfusion pressure levels above 50 mmHg where the optic nerve is normoxic. Medical intervention can affect optic nerve oxygen......-oxygenase inhibitor, indomethacin, which indicates that prostaglandin metabolism plays a role. Laboratory studies suggest that carbonic anhydrase inhibitors might be useful for medical treatment of optic nerve and retinal ischemia, potentially in diseases such as glaucoma and diabetic retinopathy. However, clinical...

  16. Airway fibroepithelial polyposis

    Directory of Open Access Journals (Sweden)

    Gonzalo Labarca

    2017-01-01

    Full Text Available Fibroepithelial polyps are benign lesions, frequently found in the skin and genitourinary tract. Airway involvement is rare, and few case reports have been published. Our patient was a 79 y.o. male smoker, who was referred to us with a 3-month history of dry cough. At physical examination, the patient looked well, but a chest CT showed a 6-mm polyp lesion in his trachea. A flexible bronchoscopy confirmed this lesion, and forceps biopsies were performed. Argon plasma coagulation was used to completely resect and treat the lesion. Pathological analysis revealed a fibroepithelial polyp (FP. The aim of this manuscript is to report a case of FP with bronchoscopic management and to review the current literature about this condition.

  17. Airway Complications After Lung Transplantation.

    Science.gov (United States)

    Frye, Laura; Machuzak, Michael

    2017-12-01

    Airway complications remain a significant source of morbidity and mortality after lung transplantation. The incidence of complications is wide-ranging depending on the definition of the event, and there is still no universally accepted grading system for airway findings after transplantation. Additionally, although surgical technique and organ preservation have improved, other modifiable risk factors remain unclear. The management is as wide-ranging as the definitions. A multimodality approach is often needed with airway stenting reserved for refractory cases and stent management by a transplant team with expertise in placement and management of long-term complications." Copyright © 2017. Published by Elsevier Inc.

  18. Neurotrophin selectivity in organizing topographic regeneration of nociceptive afferents.

    Science.gov (United States)

    Kelamangalath, Lakshmi; Tang, Xiaoqing; Bezik, Kathleen; Sterling, Noelle; Son, Young-Jin; Smith, George M

    2015-09-01

    Neurotrophins represent some of the best candidates to enhance regeneration. In the current study, we investigated the effects of artemin, a member of the glial derived neurotrophic factor (GDNF) family, on sensory axon regeneration following a lumbar dorsal root injury and compared these effects with that observed after either NGF or GDNF expression in the rat spinal cord. Unlike previously published data, artemin failed to induce regeneration of large-diameter myelinated sensory afferents when expressed within either the spinal cord or DRG. However, artemin or NGF induced regeneration of calcitonin gene related peptide positive (CGRP(+)) axons only when expressed within the spinal cord. Accordingly, artemin or NGF enhanced recovery of only nociceptive behavior and showed a cFos distribution similar to the topography of regenerating axons. Artemin and GDNF signaling requires binding to different co-receptors (GFRα3 or GFRα1, respectively) prior to binding to the signaling receptor, cRet. Approximately 70% of DRG neurons express cRet, but only 35% express either co-receptor. To enhance artemin-induced regeneration, we co-expressed artemin with either GFRα3 or GDNF. Co-expression of artemin and GFRα3 only slightly enhanced regeneration of IB4(+) non-peptidergic nociceptive axons, but not myelinated axons. Interestingly, this co-expression also disrupted the ability of artemin to produce topographic targeting and lead to significant increases in cFos immunoreactivity within the deep dorsal laminae. This study failed to demonstrate artemin-induced regeneration of myelinated axons, even with co-expression of GFRα3, which only promoted mistargeted regeneration. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Astrocytes promote peripheral nerve injury-induced reactive synaptogenesis in the neonatal CNS.

    Science.gov (United States)

    Lo, Fu-Sun; Zhao, Shuxin; Erzurumlu, Reha S

    2011-12-01

    Neonatal damage to the trigeminal nerve leads to "reactive synaptogenesis" in the brain stem sensory trigeminal nuclei. In vitro models of brain injury-induced synaptogenesis have implicated an important role for astrocytes. In this study we tested the role of astrocyte function in reactive synaptogenesis in the trigeminal principal nucleus (PrV) of neonatal rats following unilateral transection of the infraorbital (IO) branch of the trigeminal nerve. We used electrophysiological multiple input index analysis (MII) to estimate the number of central trigeminal afferent fibers that converge onto single barrelette neurons. In the developing PrV, about 30% of afferent connections are eliminated within 2 postnatal weeks. After neonatal IO nerve damage, multiple trigeminal inputs (2.7 times that of the normal inputs) converge on single barrelette cells within 3-5 days; they remain stable up to the second postnatal week. Astrocyte proliferation and upregulation of astrocyte-specific proteins (GFAP and ALDH1L1) accompany reactive synaptogenesis in the IO nerve projection zone of the PrV. Pharmacological blockade of astrocyte function, purinergic receptors, and thrombospondins significantly reduced or eliminated reactive synaptogenesis without changing the MII in the intact PrV. GFAP immunohistochemistry further supported these electrophysiological results. We conclude that immature astrocytes, purinergic receptors, and thrombospondins play an important role in reactive synaptogenesis in the peripherally deafferented neonatal PrV.

  20. Transcutaneous vagus nerve stimulation (tVNS) enhances divergent thinking.

    Science.gov (United States)

    Colzato, Lorenza S; Ritter, Simone M; Steenbergen, Laura

    2018-03-01

    Creativity is one of the most important cognitive skills in our complex and fast-changing world. Previous correlative evidence showed that gamma-aminobutyric acid (GABA) is involved in divergent but not convergent thinking. In the current study, a placebo/sham-controlled, randomized between-group design was used to test a causal relation between vagus nerve and creativity. We employed transcutaneous vagus nerve stimulation (tVNS), a novel non-invasive brain stimulation technique to stimulate afferent fibers of the vagus nerve and speculated to increase GABA levels, in 80 healthy young volunteers. Creative performance was assessed in terms of divergent thinking (Alternate Uses Task) and convergent thinking tasks (Remote Associates Test, Creative Problem Solving Task, Idea Selection Task). Results demonstrate active tVNS, compared to sham stimulation, enhanced divergent thinking. Bayesian analysis reported the data to be inconclusive regarding a possible effect of tVNS on convergent thinking. Therefore, our findings corroborate the idea that the vagus nerve is causally involved in creative performance. Even thought we did not directly measure GABA levels, our results suggest that GABA (likely to be increased in active tVNS condition) supports the ability to select among competing options in high selection demand (divergent thinking) but not in low selection demand (convergent thinking). Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Disfunção temporária do nervo lingual após uso de máscara laríngea: relato de caso Disfunción temporal del nervio lingual trás del uso de máscara laríngea: relato de caso Temporary lingual nerve dysfunction following the use of the laryngeal mask airway: report

    Directory of Open Access Journals (Sweden)

    Hugo Eckener Dantas de Pereira Cardoso

    2007-08-01

    ño tres. El volumen aplicado para insuflación del globo fue de 30 mL de aire. Después de la primera hora del postoperatorio, se inició el cuadro de adormecimiento y dolor en la garganta y en los dos tercios posteriores de la lengua que evolucionó en 24 horas con pérdida de la percepción del sabor de los alimentos. La sospecha diagnóstica fue de neuropraxia del nervio lingual por el uso de máscara laríngea. Este cuadro se mantuvo por tres semanas, período en que se obtuvo una resolución de los síntomas. CONCLUSIÓN: Complicaciones después del uso de máscara laríngea, a pesar de no frecuentes, pueden ocurrir. La neuropraxia del nervio lingual es una de ellas. Su diagnóstico es clínico y su evolución es favorable con resolución de los síntomas en semanas o meses.BACKGROUND AND OBJECTIVES: The laryngeal mask has been frequently used in Anesthesiology. Although the rate of complications with this technique is smaller than that of the endotracheal tube, it is not devoid of risks, especially in cases of difficult airways. The objective of this study was to report a case of unilateral lingual nerve damage after the use of the laryngeal mask airway. CASE REPORT: A female patient underwent a surgical procedure for removal of bilateral breast prosthesis under general, balanced anesthesia, with a size three laryngeal mask. The balloon was inflated with 30 mL of air. After the first postoperative hour, she developed decreased sensation and pain in the oropharynx and posterior two thirds of the tongue, which evolved for loss of taste in the next 24 hours. A tentative diagnosis of lingual nerve neuropraxis secondary to the use of the laryngeal mask was made. After three weeks, her symptoms subsided. CONCLUSION: Although complications after the use of the laryngeal mask airway are rare, they do occur, and neuropraxis of the lingual nerve is one of them. The diagnosis is clinical and it has a good outcome, with resolution of the symptoms within a few weeks or months.

  2. Imaging the trigeminal nerve

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-05-15

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

  3. Stenting of major airway constriction

    International Nuclear Information System (INIS)

    Wu Xiaomei

    2002-01-01

    Objective: To investigate the correlated issues in the stenting treatment of major airway constriction. Methods: Nineteen cases of major airway stenting procedure were studied retrospectively. The clinical choice of stents of different advantages or deficiencies were discussed. The importance of intravenous anesthesia supporting, life-parameters monitoring during the procedures and the prevention of complications were analysed. Results: Under intravenous and local anesthesia, 19 Wallstents had been successively placed and relieved 19 cases of major airway constrictions due to malignant or benign diseases (15 of tumors, 3 of tuberculosis, 1 of tracheomalacia). Intravenous anesthesia and life-parameters monitoring had made the procedures more safe and precise. Conclusions: Major airway stenting is an reliable method for relieving tracheobronchial stenosis; and intravenous anesthesia supporting and life-parameters monitoring guarantee the satisfactions of procedures

  4. Airway management and morbid obesity

    DEFF Research Database (Denmark)

    Kristensen, Michael S

    2010-01-01

    Morbidly obese patients present with excess fatty tissue externally on the breast, neck, thoracic wall and abdomen and internally in the mouth, pharynx and abdomen. This excess tissue tends to make access (intubation, tracheostomy) to and patency (during sedation or mask ventilation) of the upper...... in morbidly obese patients and should be followed by actions to counteract atelectasis formation. The decision as to weather to use a rapid sequence induction, an awake intubation or a standard induction with hypnotics should depend on the thorough airway examination and comorbidity and should not be based...... solely on whether morbid obesity is present or not. It is important to ensure sufficient depth of anaesthesia before initiating manipulation of the airway because inadequate anaesthesia depth predisposes to aspiration if airway management becomes difficult. The intubating laryngeal mask airway is more...

  5. The NK-2 receptor antagonist SR 48968C does not improve adenosine hyperresponsiveness and airway obstruction in allergic asthma

    NARCIS (Netherlands)

    Kraan, J; Vink-Klooster, H; Postma, DS

    Background When stimulated, excitatory nonadrenergic noncholinergic (e-NANC) nerves locally release tachykinins like Neurokinin (NK) A and Substance P, causing neurogenic inflammation and airway obstruction via activation of specific NK-1 and NK-2 receptors. The recently developed nonpeptide NK-2

  6. Understanding the Haemodynamic response to Laryngoscopy and ...

    African Journals Online (AJOL)

    It is however believed to be a reflex sympathetic and sympatho-adrenal response to airway stimulation or irritation. While the afferent limb of the reflex arc is via the cranial nerves of the upper airway, the efferent limb is via the sympathetic nerves. However, the central integrating station is not satisfactorily described in the ...

  7. Functional analysis of ultra high information rates conveyed by rat vibrissal primary afferents

    Directory of Open Access Journals (Sweden)

    André eMaia Chagas

    2013-12-01

    Full Text Available Sensory receptors determine the type and the quantity of information available for perception. Here, we quantified and characterized the information transferred by primary afferents in the rat whisker system using neural system identification. Quantification of ‘how much’ information is conveyed by primary afferents, using the direct method, a classical information theoretic tool, revealed that primary afferents transfer huge amounts of information (up to 529 bits/s. Information theoretic analysis of instantaneous spike-triggered kinematic stimulus features was used to gain functional insight on ‘what’ is coded by primary afferents. Amongst the kinematic variables tested - position, velocity, and acceleration - primary afferent spikes encoded velocity best. The other two variables contribute to information transfer, but only if combined with velocity. We further revealed three additional characteristics that play a role in information transfer by primary afferents. Firstly, primary afferent spikes show preference for well separated multiple stimuli (i.e. well separated sets of combinations of the three instantaneous kinematic variables. Secondly, spikes are sensitive to short strips of the stimulus trajectory (up to 10 ms pre-spike time, and thirdly, they show spike patterns (precise doublet and triplet spiking. In order to deal with these complexities, we used a flexible probabilistic neuron model fitting mixtures of Gaussians to the spike triggered stimulus distributions, which quantitatively captured the contribution of the mentioned features and allowed us to achieve a full functional analysis of the total information rate indicated by the direct method. We found that instantaneous position, velocity, and acceleration explained about 50% of the total information rate. Adding a 10 ms pre-spike interval of stimulus trajectory achieved 80-90%. The final 10-20% were found to be due to non-linear coding by spike bursts.

  8. Antimicrobial peptides in the airway.

    Science.gov (United States)

    Laube, D M; Yim, S; Ryan, L K; Kisich, K O; Diamond, G

    2006-01-01

    The airway provides numerous defense mechanisms to prevent microbial colonization by the large numbers of bacteria and viruses present in ambient air. An important component of this defense is the antimicrobial peptides and proteins present in the airway surface fluid (ASF), the mucin-rich fluid covering the respiratory epithelium. These include larger proteins such as lysozyme and lactoferrin, as well as the cationic defensin and cathelicidin peptides. While some of these peptides, such as human beta-defensin (hBD)-1, are present constitutively, others, including hBD2 and -3 are inducible in response to bacterial recognition by Toll-like receptor-mediated pathways. These peptides can act as microbicides in the ASF, but also exhibit other activities, including potent chemotactic activity for cells of the innate and adaptive immune systems, suggesting they play a complex role in the host defense of the airway. Inhibition of antimicrobial peptide activity or gene expression can result in increased susceptibility to infections. This has been observed with cystic fibrosis (CF), where the CF phenotype leads to reduced antimicrobial capacity of peptides in the airway. Pathogenic virulence factors can inhibit defensin gene expression, as can environmental factors such as air pollution. Such an interference can result in infections by airway-specific pathogens including Bordetella bronchiseptica, Mycobacterium tuberculosis, and influenza virus. Research into the modulation of peptide gene expression in animal models, as well as the optimization of peptide-based therapeutics shows promise for the treatment and prevention of airway infectious diseases.

  9. Greater palatine nerve neuropraxia after laryngeal mask insertion: A rare occurrence

    Directory of Open Access Journals (Sweden)

    Jyoti Garg

    2017-01-01

    Full Text Available With the more frequent use of the laryngeal mask airway (LMA over endotracheal tubes for general anaesthesia, various cranial nerve injuries have been reported recently. We report a rare occurrence of greater palatine nerve (GPN palsy subsequent to the use of LMA Supreme™ in a young female scheduled for hand surgery. Although the exact mechanism of a nerve injury is still a matter of further research, we postulate pressure neuropraxia of GPN as a causative factor in the development of numbness over the hard palate after the removal of LMA in the post operative period.

  10. Vessel-guided airway tree segmentation

    DEFF Research Database (Denmark)

    Lo, Pechin Chien Pau; Sporring, Jon; Ashraf, Haseem

    2010-01-01

    method is evaluated on 250 low dose computed tomography images from a lung cancer screening trial. Our experiments showed that applying the region growing algorithm on the airway appearance model produces more complete airway segmentations, leading to on average 20% longer trees, and 50% less leakage......This paper presents a method for airway tree segmentation that uses a combination of a trained airway appearance model, vessel and airway orientation information, and region growing. We propose a voxel classification approach for the appearance model, which uses a classifier that is trained...... to differentiate between airway and non-airway voxels. This is in contrast to previous works that use either intensity alone or hand crafted models of airway appearance. We show that the appearance model can be trained with a set of easily acquired, incomplete, airway tree segmentations. A vessel orientation...

  11. Membrane Mechanics of Primary Afferent Neurons in the Dorsal Root Ganglia of Rats.

    Science.gov (United States)

    Kanda, Hirosato; Gu, Jianguo G

    2017-04-25

    Membrane mechanics is an important biological factor regulating many cellular functions including cell motility, intercellular and intracellular signaling, gene expression, and membrane ion channel activity. Primary afferent neurons transduce sensory information about temperature, touch, and pain. These sensory functions may be profoundly affected by the states of primary afferent neuron mechanics. However, membrane mechanics of primary afferent neurons is largely unknown. In this study, we established the optical trapping technique for determining membrane mechanics of cultured primary afferent neurons of the dorsal root ganglia (DRG). We further determined the roles of cytoskeleton and membrane lipids in DRG neuron mechanics. We found that DRG neurons had a plasma membrane tension of ∼54 pN/μm, and the tension was significantly decreased to ∼29 pN/μm by cytochalasin D treatment to disrupt actin cytoskeleton and increased to ∼79 pN/μm by methyl-β-cyclodextrin treatment to sequester membrane cholesterol. DRG neuron membrane stiffness was not significantly affected by the cytoskeleton disruption but was significantly increased after cholesterol sequestration. Our findings elucidate membrane mechanical properties of primary afferent neurons, which provide, to our knowledge, a new perspective on their sensory functions. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  12. Emotional proprioception: Treatment of depression with afferent facial feedback.

    Science.gov (United States)

    Finzi, Eric; Rosenthal, Norman E

    2016-09-01

    We develop the concept of emotional proprioception, whereby the muscles of facial expression play a central role in encoding and transmitting information to the brain's emotional circuitry, and describe its underlying neuroanatomy. We explore the role of facial expression in both reflecting and influencing depressed mood. The circuitry involved in this latter effect is a logical target for treatment with botulinum toxin, and we review the evidence in support of this strategy. Clinical trial data suggest that botulinum toxin is effective in treating depression. We discuss the clinical and theoretical implications of these data. This novel treatment approach is just one example of the potential importance of the cranial nerves in the treatment of depression. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Nanofiber Nerve Guide for Peripheral Nerve Repair and Regeneration

    Science.gov (United States)

    2016-04-01

    project was to develop an alternative to autologous nerve grafts used in repair of peripheral nerve injuries in war and civilian life. Based on our...gradient compositions tested in Aim 1 in preparation to studies in the large animal model of peripheral nerve injury and repair . As it was not...this specific aim was to test the efficacy of optimized nanofiber nerve guide in a canine model of peripheral nerve injury and repair . Peripheral nerve

  14. Multiscale Vessel-guided Airway Tree Segmentation

    DEFF Research Database (Denmark)

    Lo, Pechin Chien Pau; Sporring, Jon; de Bruijne, Marleen

    2009-01-01

    This paper presents a method for airway tree segmentation that uses a combination of a trained airway appearance model, vessel and airway orientation information, and region growing. The method uses a voxel classification based appearance model, which involves the use of a classifier that is trai......This paper presents a method for airway tree segmentation that uses a combination of a trained airway appearance model, vessel and airway orientation information, and region growing. The method uses a voxel classification based appearance model, which involves the use of a classifier...

  15. Immobilization induces changes in presynaptic control of group Ia afferents in healthy humans

    DEFF Research Database (Denmark)

    Jensen, Jesper Lundbye; Nielsen, Jens Bo

    2008-01-01

    Neural plasticity occurs throughout adult life in response to maturation, use and disuse. Recent studies have documented that H-reflex amplitudes increase following a period of immobilization. To elucidate the mechanisms contributing to the increase in H-reflex size following immobilization we...... immobilized the left foot and ankle joint for 2 weeks in 12 able-bodied subjects. Disynaptic reciprocal inhibition of soleus (SOL) motoneurones and presynaptic control of SOL group Ia afferents was measured before and after the immobilization as well as following 2 weeks of recovery. Following immobilization...... inhibition of SOL Ia afferents and taken together suggest that GABAergic presynaptic inhibition of the SOL Ia afferents is decreased following 2 weeks of immobilization. The depression of the SOL H-reflex when evoked at intervals shorter than 10 s (homosynaptic post-activation depression) also decreased...

  16. Monosynaptic connections between primary afferents and giant neurons in the turtle spinal dorsal horn

    DEFF Research Database (Denmark)

    Fernández, A; Radmilovich, M; Russo, R E

    1996-01-01

    This paper reports the occurrence of monosynaptic connections between dorsal root afferents and a distinct cell type-the giant neuron-deep in the dorsal horn of the turtle spinal cord. Light microscope studies combining Nissl stain and transganglionic HRP-labeling of the primary afferents have...... recording in spinal cord slices provided functional evidence indicating the monosynaptic connections between dorsal root afferents and giant neurons. The recorded neurons were morphologically identified by means of biocytin injection and with avidin conjugates. Electrical stimulation of the ipsilateral...... dorsal roots evoked synaptic responses with short, fixed latencies (1.6-5.6 ms), which remained unchanged at high frequencies (10 Hz). Excitatory polysynaptic potentials were also observed. By means of pharmacological procedures the short-latency response was dissected in two components: one insensitive...

  17. Structure of the Afferent Terminals in Terminal Ganglion of a Cricket and Persistent Homology

    Science.gov (United States)

    Brown, Jacob; Gedeon, Tomáš

    2012-01-01

    We use topological data analysis to investigate the three dimensional spatial structure of the locus of afferent neuron terminals in crickets Acheta domesticus. Each afferent neuron innervates a filiform hair positioned on a cercus: a protruding appendage at the rear of the animal. The hairs transduce air motion to the neuron signal that is used by a cricket to respond to the environment. We stratify the hairs (and the corresponding afferent terminals) into classes depending on hair length, along with position. Our analysis uncovers significant structure in the relative position of these terminal classes and suggests the functional relevance of this structure. Our method is very robust to the presence of significant experimental and developmental noise. It can be used to analyze a wide range of other point cloud data sets. PMID:22649516

  18. Structure of the afferent terminals in terminal ganglion of a cricket and persistent homology.

    Directory of Open Access Journals (Sweden)

    Jacob Brown

    Full Text Available We use topological data analysis to investigate the three dimensional spatial structure of the locus of afferent neuron terminals in crickets Acheta domesticus. Each afferent neuron innervates a filiform hair positioned on a cercus: a protruding appendage at the rear of the animal. The hairs transduce air motion to the neuron signal that is used by a cricket to respond to the environment. We stratify the hairs (and the corresponding afferent terminals into classes depending on hair length, along with position. Our analysis uncovers significant structure in the relative position of these terminal classes and suggests the functional relevance of this structure. Our method is very robust to the presence of significant experimental and developmental noise. It can be used to analyze a wide range of other point cloud data sets.

  19. Isolated optic nerve pseudotumour

    International Nuclear Information System (INIS)

    Patankar, T.; Prasad, S.; Krishnan, A.; Laxminarayan, R.

    2000-01-01

    Isolated optic nerve involvement by the idiopathic inflammatory process is a rare finding and very few reports are available. Here a case of an isolated optic nerve inflammatory pseudotumour presenting with gradually progressive unilateral loss of vision is described. It showed dramatic response to a trial of steroids and its differential diagnoses are discussed. Copyright (1999) Blackwell Science Pty Ltd

  20. Diabetic Nerve Problems

    Science.gov (United States)

    ... vessels that bring oxygen to your nerves. Damaged nerves may stop sending messages, or may send messages slowly or at the wrong times. This damage is called diabetic neuropathy. Over half of people with diabetes get it. Symptoms may include Numbness in your ...

  1. Purinergic signaling in the airways.

    Science.gov (United States)

    Burnstock, Geoffrey; Brouns, Inge; Adriaensen, Dirk; Timmermans, Jean-Pierre

    2012-10-01

    Evidence for a significant role and impact of purinergic signaling in normal and diseased airways is now beyond dispute. The present review intends to provide the current state of knowledge of the involvement of purinergic pathways in the upper and lower airways and lungs, thereby differentiating the involvement of different tissues, such as the epithelial lining, immune cells, airway smooth muscle, vasculature, peripheral and central innervation, and neuroendocrine system. In addition to the vast number of well illustrated functions for purinergic signaling in the healthy respiratory tract, increasing data pointing to enhanced levels of ATP and/or adenosine in airway secretions of patients with airway damage and respiratory diseases corroborates the emerging view that purines act as clinically important mediators resulting in either proinflammatory or protective responses. Purinergic signaling has been implicated in lung injury and in the pathogenesis of a wide range of respiratory disorders and diseases, including asthma, chronic obstructive pulmonary disease, inflammation, cystic fibrosis, lung cancer, and pulmonary hypertension. These ostensibly enigmatic actions are based on widely different mechanisms, which are influenced by the cellular microenvironment, but especially the subtypes of purine receptors involved and the activity of distinct members of the ectonucleotidase family, the latter being potential protein targets for therapeutic implementation.

  2. Peptide and lipid modulation of glutamatergic afferent synaptic transmission in the solitary tract nucleus

    Directory of Open Access Journals (Sweden)

    Michael C. Andresen

    2013-01-01

    Full Text Available The brainstem nucleus of the solitary tract (NTS holds the first central neurons in major homeostatic reflex pathways. These homeostatic reflexes regulate and coordinate multiple organ systems from gastrointestinal to cardiopulmonary functions. The core of many of these pathways arise from cranial visceral afferent neurons that enter the brain as the solitary tract (ST with more than two-thirds arising from the gastrointestinal system. About one quarter of ST afferents have myelinated axons but the majority are classed as unmyelinated C-fibers. All ST afferents release the fast neurotransmitter glutamate with remarkably similar, high-probability release characteristics. Second order NTS neurons receive surprisingly limited primary afferent information with one or two individual inputs converging on single second order NTS neurons. A- and C-fiber afferents never mix at NTS second order neurons. Many transmitters modify the basic glutamatergic excitatory postsynaptic current (EPSC often by reducing glutamate release or interrupting terminal depolarization. Thus, a distinguishing feature of ST transmission is presynaptic expression of G-protein coupled receptors for peptides common to peripheral or forebrain (e.g. hypothalamus neuron sources. Presynaptic receptors for angiotensin (AT1, vasopressin (V1a, oxytocin (OT, opioid (MOR, ghrelin (GHSR1 and cholecystokinin (CCK differentially control glutamate release on particular subsets of neurons with most other ST afferents unaffected. Lastly, lipid-like signals are transduced by two key ST presynaptic receptors, the transient receptor potential vanilloid type 1 (TRPV1 and the cannabinoid receptor (CB1 that oppositely control glutamate release. Increasing evidence suggests that peripheral nervous signaling mechanisms are repurposed at central terminals to control excitation and are major sites of signal integration of peripheral and central inputs particularly from the hypothalamus.

  3. Firing of antagonist small-diameter muscle afferents reduces voluntary activation and torque of elbow flexors.

    Science.gov (United States)

    Kennedy, David S; McNeil, Chris J; Gandevia, Simon C; Taylor, Janet L

    2013-07-15

    During muscle fatigue, firing of small-diameter muscle afferents can decrease voluntary activation of the fatigued muscle. However, these afferents may have a more widespread effect on other muscles in the exercising limb. We examined if the firing of fatigue-sensitive afferents from elbow extensor muscles in the same arm reduces torque production and voluntary activation of elbow flexors. In nine subjects we examined voluntary activation of elbow flexors by measuring changes in superimposed twitches evoked by transcranial magnetic stimulation of the motor cortex during brief (2-3 s) maximal voluntary contractions (MVC). Inflation of a blood pressure cuff following a 2-min sustained MVC blocked blood flow to the fatigued muscle and maintained firing of small-diameter afferents. After a fatiguing elbow flexion contraction, maximal flexion torque was lower (26.0 ± 4.4% versus 67.9 ± 5.2% of initial maximal torque; means ± s.d.; P torque was also reduced (82.2 ± 4.9% versus 91.4 ± 2.3% of initial maximal torque; P = 0.007), superimposed twitches were larger (2.7 ± 0.7% versus 1.3 ± 0.2% ongoing MVC; P = 0.02) and voluntary activation lower (81.6 ± 8.2% versus 95.5 ± 6.9%; P = 0.04) with than without ischaemia. After a fatiguing contraction, voluntary drive to the fatigued muscles is reduced with continued input from small-diameter muscle afferents. Furthermore, fatigue of the elbow extensor muscles decreases voluntary drive to unfatigued elbow flexors of the same arm. Therefore, firing of small-diameter muscle afferents from one muscle can affect voluntary activation and hence torque generation of another muscle in the same limb.

  4. Direct and indirect regulation of spinal cord Ia afferent terminal formation by the γ-Protocadherins

    Directory of Open Access Journals (Sweden)

    Tuhina ePrasad

    2011-12-01

    Full Text Available The Pcdh-γ gene cluster encodes 22 protocadherin adhesion molecules that interact as homophilic multimers and critically regulate synaptogenesis and apoptosis of interneurons in the developing spinal cord. Unlike interneurons, the two primary components of the monosynaptic stretch reflex circuit, dorsal root ganglion sensory neurons and ventral motor neurons, do not undergo excessive apoptosis in Pcdh-γdel/del null mutants, which die shortly after birth. However, as we show here, mutants exhibit severely disorganized Ia proprioceptive afferent terminals in the ventral horn. In contrast to the fine net-like pattern observed in wild-type mice, central Ia terminals in Pcdh-γ mutants are expanded, clumped, and fill the space between individual motor neurons; quantitative analysis shows a ~2.5 fold increase in the area of terminals. Concomitant with this, there is a 70% loss of the collaterals that Ia afferents extend to ventral interneurons, many of which undergo apoptosis in the mutants. The Ia afferent phenotype is ameliorated, though not entirely rescued, when apoptosis is blocked in Pcdh-γ null mice by introduction of a Bax null allele. This indicates that loss of ventral interneurons, which act as intermediate Ia afferent targets, contributes to the disorganization of terminals on motor pools. Restricted mutation of the Pcdh-γ cluster using conditional mutants and multiple Cre transgenic lines (Wnt1-Cre for sensory neurons; Pax2-Cre for ventral interneurons; Hb9-Cre for motor neurons also revealed a direct requirement for the γ-Pcdhs in Ia neurons and ventral interneurons, but not in motor neurons themselves. Together, these genetic manipulations indicate that the γ-Pcdhs are required for the formation of the Ia afferent circuit in two ways: First, they control the survival of ventral interneurons that act as intermediate Ia targets; and second, they provide a homophilic molecular cue between Ia afferents and target ventral interneurons.

  5. Systemic administration of monosodium glutamate elevates intramuscular glutamate levels and sensitizes rat masseter muscle afferent fibers.

    Science.gov (United States)

    Cairns, Brian E; Dong, Xudong; Mann, Mandeep K; Svensson, Peter; Sessle, Barry J; Arendt-Nielsen, Lars; McErlane, Keith M

    2007-11-01

    There is evidence that elevated tissue concentrations of glutamate may contribute to pain and sensitivity in certain musculoskeletal pain conditions. In the present study, the food additive monosodium glutamate (MSG) was injected intravenously into rats to determine whether it could significantly elevate interstitial concentrations of glutamate in the masseter muscle and whether MSG administration could excite and/or sensitize slowly conducting masseter afferent fibers through N-methyl-D-aspartate (NMDA) receptor activation. The interstitial concentration of glutamate after systemic injection of isotonic phosphate-buffered saline (control) or MSG (10 and 50mg/kg) was measured with a glutamate-selective biosensor. The pre-injection baseline interstitial concentration of glutamate in the rat masseter muscle was 24+/-11 microM. Peak interstitial concentration after injection of 50mg/kg MSG was 63+/-18 microM and remained elevated above baseline for approximately 18 min. In vivo single unit recording experiments were undertaken to assess the effect of MSG (50mg/kg) on masseter afferent fibers. Injection of MSG evoked a brief discharge in one afferent fiber, and significantly decreased ( approximately 25%) the average afferent mechanical threshold (n=10) during the first 5 min after injection of MSG. Intravenous injection of ketamine (1mg/kg), 5 min prior to MSG, prevented the MSG-induced decreases in the mechanical threshold of masseter afferent fibers. The present results indicate that a 2- to 3-fold elevation in interstitial glutamate levels in the masseter muscle is sufficient to excite and induce afferent mechanical sensitization through NMDA receptor activation. These findings suggest that modest elevations of interstitial glutamate concentration could alter musculoskeletal pain sensitivity in humans.

  6. Expression of taste receptors in Solitary Chemosensory Cells of rodent airways

    Directory of Open Access Journals (Sweden)

    Sbarbati Andrea

    2011-01-01

    Full Text Available Abstract Background Chemical irritation of airway mucosa elicits a variety of reflex responses such as coughing, apnea, and laryngeal closure. Inhaled irritants can activate either chemosensitive free nerve endings, laryngeal taste buds or solitary chemosensory cells (SCCs. The SCC population lies in the nasal respiratory epithelium, vomeronasal organ, and larynx, as well as deeper in the airway. The objective of this study is to map the distribution of SCCs within the airways and to determine the elements of the chemosensory transduction cascade expressed in these SCCs. Methods We utilized a combination of immunohistochemistry and molecular techniques (rtPCR and in situ hybridization on rats and transgenic mice where the Tas1R3 or TRPM5 promoter drives expression of green fluorescent protein (GFP. Results Epithelial SCCs specialized for chemoreception are distributed throughout much of the respiratory tree of rodents. These cells express elements of the taste transduction cascade, including Tas1R and Tas2R receptor molecules, α-gustducin, PLCβ2 and TrpM5. The Tas2R bitter taste receptors are present throughout the entire respiratory tract. In contrast, the Tas1R sweet/umami taste receptors are expressed by numerous SCCs in the nasal cavity, but decrease in prevalence in the trachea, and are absent in the lower airways. Conclusions Elements of the taste transduction cascade including taste receptors are expressed by SCCs distributed throughout the airways. In the nasal cavity, SCCs, expressing Tas1R and Tas2R taste receptors, mediate detection of irritants and foreign substances which trigger trigeminally-mediated protective airway reflexes. Lower in the respiratory tract, similar chemosensory cells are not related to the trigeminal nerve but may still trigger local epithelial responses to irritants. In total, SCCs should be considered chemoreceptor cells that help in preventing damage to the respiratory tract caused by inhaled irritants and

  7. Monosynaptic connections between primary afferents and giant neurons in the turtle spinal dorsal horn

    DEFF Research Database (Denmark)

    Fernández, A; Radmilovich, M; Russo, R E

    1996-01-01

    This paper reports the occurrence of monosynaptic connections between dorsal root afferents and a distinct cell type-the giant neuron-deep in the dorsal horn of the turtle spinal cord. Light microscope studies combining Nissl stain and transganglionic HRP-labeling of the primary afferents have...... revealed the occurrence of axosomatic and axodendritic contacts between labeled boutons and giant neurons. The synaptic nature of these contacts has been confirmed by use of electron microscope procedures involving the partial three-dimensional reconstruction of identified giant neurons. Intracellular...

  8. Postoperative Airway Obstruction by a Bone Fragment

    Directory of Open Access Journals (Sweden)

    Patrick Schober

    2017-01-01

    Full Text Available Postoperative airway obstructions are potentially life-threatening complications. These obstructions may be classified as functional (sagging tongue, laryngospasm, or bronchospasm, pathoanatomical (airway swelling or hematoma within the airways, or foreign body-related. Various cases of airway obstruction by foreign bodies have previously been reported, for example, by broken teeth or damaged airway instruments. Here we present the exceptional case of a postoperative airway obstruction due to a large fragment of the patient’s maxillary bone, left accidentally in situ after transoral surgical tumor resection. Concerning this type of airway obstruction, we discuss possible causes, diagnosis, and treatment options. Although it is an exceptional case after surgery, clinicians should be aware of this potentially life-threatening complication. In summary, this case demonstrates that the differential diagnosis of postoperative airway obstructions should include foreign bodies derived from surgery, including tissue and bone fragments.

  9. Clinical review: Management of difficult airways

    Science.gov (United States)

    Langeron, Olivier; Amour, Julien; Vivien, Benoît; Aubrun, Frédéric

    2006-01-01

    Difficulties or failure in airway management are still important factors in morbidity and mortality related to anesthesia and intensive care. A patent and secure airway is essential to manage anesthetized or critically ill patients. Oxygenation maintenance during tracheal intubation is the cornerstone of difficult airway management and is always emphasized in guidelines. The occurrence of respiratory adverse events has decreased in claims for injuries due to inadequate airway management mainly at induction of anesthesia. Nevertheless, claim reports emphasize that airway emergencies, tracheal extubation and/or recovery of anesthesia phases are still associated with death or brain damage, indicating that additional educational support and management strategies to improve patient safety are required. The present brief review analyses specific problems of airway management related to difficult tracheal intubation and to difficult mask ventilation prediction. The review will focus on basic airway management including preoxygenation, and on some oxygenation and tracheal intubation techniques that may be performed to solve a difficult airway. PMID:17184555

  10. Clinical review: management of difficult airways.

    Science.gov (United States)

    Langeron, Olivier; Amour, Julien; Vivien, Benoît; Aubrun, Frédéric

    2006-01-01

    Difficulties or failure in airway management are still important factors in morbidity and mortality related to anesthesia and intensive care. A patent and secure airway is essential to manage anesthetized or critically ill patients. Oxygenation maintenance during tracheal intubation is the cornerstone of difficult airway management and is always emphasized in guidelines. The occurrence of respiratory adverse events has decreased in claims for injuries due to inadequate airway management mainly at induction of anesthesia. Nevertheless, claim reports emphasize that airway emergencies, tracheal extubation and/or recovery of anesthesia phases are still associated with death or brain damage, indicating that additional educational support and management strategies to improve patient safety are required. The present brief review analyses specific problems of airway management related to difficult tracheal intubation and to difficult mask ventilation prediction. The review will focus on basic airway management including preoxygenation, and on some oxygenation and tracheal intubation techniques that may be performed to solve a difficult airway.

  11. Extraction of Airways from CT (EXACT'09)

    NARCIS (Netherlands)

    Lo, P.; Ginneken, B. van; Reinhardt, J.M.; Tarunashree, Y.; Jong, P.A. de; Irving, B.; Fetita, C.; Ortner, M.; Pinho, R.; Sijbers, J.; Feuerstein, M.; Fabijanska, A.; Bauer, C.; Beichel, R.; Mendoza, C.S.; Wiemker, R.; Lee, J. van der; Reeves, A.P.; Born, S.; Weinheimer, O.; Rikxoort, E.M. van; Tschirren, J.; Mori, K.; Odry, B.; Naidich, D.P.; Hartmann, I.J.; Hoffman, E.A.; Prokop, M.; Pedersen, J.H.; de Bruijne, M.

    2012-01-01

    This paper describes a framework for establishing a reference airway tree segmentation, which was used to quantitatively evaluate fifteen different airway tree extraction algorithms in a standardized manner. Because of the sheer difficulty involved in manually constructing a complete reference

  12. Airway management and morbid obesity

    DEFF Research Database (Denmark)

    Kristensen, Michael S

    2010-01-01

    airway and the function of the lungs (decreased residual capacity and aggravated ventilation perfusion mismatch) worse than in lean patients. Proper planning and preparation of airway management is essential, including elevation of the patient's upper body, head and neck. Preoxygenation is mandatory......Morbidly obese patients present with excess fatty tissue externally on the breast, neck, thoracic wall and abdomen and internally in the mouth, pharynx and abdomen. This excess tissue tends to make access (intubation, tracheostomy) to and patency (during sedation or mask ventilation) of the upper...... in morbidly obese patients and should be followed by actions to counteract atelectasis formation. The decision as to weather to use a rapid sequence induction, an awake intubation or a standard induction with hypnotics should depend on the thorough airway examination and comorbidity and should not be based...

  13. Comparing the Laryngeal Mask Airway, Cobra Perilaryngeal Airway and Face Mask in Children Airway Management.

    Science.gov (United States)

    Tekin, Beyza; Hatipoğlu, Zehra; Türktan, Mediha; Özcengiz, Dilek

    2016-04-01

    We compared the effects of the laryngeal mask airway (LMA), face mask and Cobra perilaryngeal airway (PLA) in the airway management of spontaneously breathing paediatric patients undergoing elective inguinal surgery. In this study, 90 cases of 1-14-year-old children undergoing elective inguinal surgery were scheduled. The patients were randomly divided into three groups. Anaesthesia was provided with sevoflurane and 50%-50% nitrous oxide and oxygen. After providing an adequate depth of anaesthesia, supraglottic airway devices were inserted in the group I and II patients. The duration and number of insertion, haemodynamic parameters, plateau and peak inspiratory pressure and positive end-expiratory pressure of the patients were recorded preoperatively, after induction and at 5, 10, 15 and 30 min peroperatively. There were no statistical differences between the groups in terms of haemodynamic parameters (p>0.05). In group II, instrumentation success was higher and instrumentation time was shorter than group II. The positive end-expiratory pressure and plateau and peak inspiratory pressure values were statistically lower in group II (pairway safety and to avoid possible complications, LMA and Cobra PLA could be alternatives to face mask and that the Cobra PLA provided lower airway pressure and had a faster and more easy placement than LMA.

  14. Clinical review: Management of difficult airways

    OpenAIRE

    Langeron, Olivier; Amour, Julien; Vivien, Benoît; Aubrun, Frédéric

    2006-01-01

    Difficulties or failure in airway management are still important factors in morbidity and mortality related to anesthesia and intensive care. A patent and secure airway is essential to manage anesthetized or critically ill patients. Oxygenation maintenance during tracheal intubation is the cornerstone of difficult airway management and is always emphasized in guidelines. The occurrence of respiratory adverse events has decreased in claims for injuries due to inadequate airway management mainl...

  15. Airway management in Ludwig's angina.

    Science.gov (United States)

    Neff, S P; Merry, A F; Anderson, B

    1999-12-01

    A 37-year-old 91 kg man presented with features of Ludwig's angina. Anaesthesia for incision and drainage of his submandibular abscess was undertaken by two specialist anaesthetists with an otorhinolaryngological surgeon prepared for immediate tracheostomy. After preoxygenation, gas induction with sevoflurane in oxygen was followed by a gush of pus into the oral cavity and laryngospam causing acute upper airway obstruction. This resolved with 25 mg of suxamethonium and an endotracheal tube was passed into the trachea with difficulty. Options for management of the difficult airway in Ludwig's angina are discussed.

  16. Neurophysiological approach to disorders of peripheral nerve

    DEFF Research Database (Denmark)

    Crone, Clarissa; Krarup, Christian

    2013-01-01

    Disorders of the peripheral nerve system (PNS) are heterogeneous and may involve motor fibers, sensory fibers, small myelinated and unmyelinated fibers and autonomic nerve fibers, with variable anatomical distribution (single nerves, several different nerves, symmetrical affection of all nerves...

  17. Emergency surgical airway management in Denmark

    DEFF Research Database (Denmark)

    Rosenstock, C V; Nørskov, A K; Wetterslev, J

    2016-01-01

    BACKGROUND: The emergency surgical airway (ESA) is the final option in difficult airway management. We identified ESA procedures registered in the Danish Anaesthesia Database (DAD) and described the performed airway management. METHODS: We extracted a cohort of 452 461 adult patients undergoing...

  18. Airway Complications following ingestion of corrosive | Ezike ...

    African Journals Online (AJOL)

    Conclusions: Corrosive ingestion is a major health problem in our environment. The proximal third of the oesophagus and the upper airway are mostly affected. These frequently result in life threatening airway complications demanding urgent tracheostomy. Key words: Corrosives, Burns, Airway, Respiratory distress.

  19. Functional phenotype of airway myocytes from asthmatic airways

    NARCIS (Netherlands)

    Wright, David B.; Trian, Thomas; Siddiqui, Sana; Pascoe, Chris D.; Ojo, Oluwaseun O.; Johnson, Jill R.; Dekkers, Bart G. J.; Dakshinamurti, Shyamala; Bagchi, Rushita; Burgess, Janette K.; Kanabar, Varsha

    In asthma, the airway smooth muscle (ASM) cell plays a central role in disease pathogenesis through cellular changes which may impact on its microenvironment and alter ASM response and function. The answer to the long debated question of what makes a 'healthy' ASM cell become 'asthmatic' still

  20. Synaptic ultrastructure changes in trigeminocervical complex posttrigeminal nerve injury.

    Science.gov (United States)

    Park, John; Trinh, Van Nancy; Sears-Kraxberger, Ilse; Li, Kang-Wu; Steward, Oswald; Luo, Z David

    2016-02-01

    Trigeminal nerves collecting sensory information from the orofacial area synapse on second-order neurons in the dorsal horn of subnucleus caudalis and cervical C1/C2 spinal cord (Vc/C2, or trigeminocervical complex), which is critical for sensory information processing. Injury to the trigeminal nerves may cause maladaptive changes in synaptic connectivity that plays an important role in chronic pain development. Here we examined whether injury to the infraorbital nerve, a branch of the trigeminal nerves, led to synaptic ultrastructural changes when the injured animals have developed neuropathic pain states. Transmission electron microscopy was used to examine synaptic profiles in Vc/C2 at 3 weeks postinjury, corresponding to the time of peak behavioral hypersensitivity following chronic constriction injury to the infraorbital nerve (CCI-ION). Using established criteria, synaptic profiles were classified as associated with excitatory (R-), inhibitory (F-), and primary afferent (C-) terminals. Each type was counted within the superficial dorsal horn of the Vc/C2 and the means from each rat were compared between sham and injured animals; synaptic contact length was also measured. The overall analysis indicates that rats with orofacial pain states had increased numbers and decreased mean synaptic length of R-profiles within the Vc/C2 superficial dorsal horn (lamina I) 3 weeks post-CCI-ION. Increases in the number of excitatory synapses in the superficial dorsal horn of Vc/C2 could lead to enhanced activation of nociceptive pathways, contributing to the development of orofacial pain states. © 2015 Wiley Periodicals, Inc.

  1. The effect of type of afferent feedback timed with motor imagery on the induction of cortical plasticity

    DEFF Research Database (Denmark)

    Mrachacz-Kersting, Natalie; Voigt, Michael; Stevenson, Andrew James Thomas

    2017-01-01

    independently of the type of afferent inflow. An afferent volley generated from a passive movement or an electrical stimulus arrives at the somatosensory cortex at similar times. It is thus likely that the similar effects observed here are strictly due to the tight coupling in time between the afferent inflow...... compared these two interventions (BCIFES and BCIpassive) where the afferent input was timed to arrive at the motor cortex during the PN of the MRCP. Twelve healthy participants attended two experimental sessions. They were asked to perform 30 dorsiflexion movements timed to a cue while continuous......: 8-35 mAmp) or a passive ankle movement (amplitude and velocity matched to a normal gait cycle) was applied such that the first afferent inflow would coincide with the PN of the MRCP. The change in the output of the primary motor cortex (M1) was quantified by applying single transcranial magnetic...

  2. Nerve transfer for sensory reconstruction of C8-T1 dermatomes in tetraplegia.

    Science.gov (United States)

    Bertelli, Jayme A; Ghizoni, Marcos F

    2016-11-01

    Absence of sensation in C8-T1 dermatome is a common finding in midcervical spinal cord injury. The goal was to restore sensation on the C8-T1 dermatomes by transferring sensory nerves with afferents on C5-C6 roots. A mean 10 months post spinal cord injury, we operated on 10 upper limbs from 5 tetraplegics averaging 23 years old. Cutaneous branches of the median nerve were transferred to the palm to the ulnar proper digital nerve of the little finger. In two patients, the lateral antebrachial cutaneous nerve was also transferred to the medial antebrachial cutaneous nerve. At a mean 20 months after surgery, on the ulnar side of the hand and little finger, all patients were able to perceive 19.3 g Semmes-Weinstein monofilament pressure. Nociception was restored on the medial side of the elbow, forearm, and hand. Faulty location was a common finding, but not as a major complaint. Sensory nerve transfers should be incorporated into the reconstruction of the upper limb in tetraplegics. © 2015 Wiley Periodicals, Inc. Microsurgery 36:637-641, 2016. © 2016 Wiley Periodicals, Inc.

  3. Prolonged ozone exposure in an allergic airway disease model: Adaptation of airway responsiveness and airway remodeling

    Directory of Open Access Journals (Sweden)

    Park Chang-Soo

    2006-02-01

    Full Text Available Abstract Background Short-term exposure to high concentrations of ozone has been shown to increase airway hyper-responsiveness (AHR. Because the changes in AHR and airway inflammation and structure after chronic ozone exposure need to be determined, the goal of this study was to investigate these effects in a murine model of allergic airway disease. Methods We exposed BALB/c mice to 2 ppm ozone for 4, 8, and 12 weeks. We measured the enhanced pause (Penh to methacholine and performed cell differentials in bronchoalveolar lavage fluid. We quantified the levels of IL-4 and IFN-γ in the supernatants of the bronchoalveolar lavage fluids using enzyme immunoassays, and examined the airway architecture under light and electron microscopy. Results The groups exposed to ozone for 4, 8, and 12 weeks demonstrated decreased Penh at methacholine concentrations of 12.5, 25, and 50 mg/ml, with a dose-response curve to the right of that for the filtered-air group. Neutrophils and eosinophils increased in the group exposed to ozone for 4 weeks compared to those in the filtered-air group. The ratio of IL-4 to INF-γ increased significantly after exposure to ozone for 8 and 12 weeks compared to the ratio for the filtered-air group. The numbers of goblet cells, myofibroblasts, and smooth muscle cells showed time-dependent increases in lung tissue sections from the groups exposed to ozone for 4, 8, and 12 weeks. Conclusion These findings demonstrate that the increase in AHR associated with the allergic airway does not persist during chronic ozone exposure, indicating that airway remodeling and adaptation following repeated exposure to air pollutants can provide protection against AHR.

  4. Is surgical airway necessary for airway management in deep neck infections and Ludwig angina?

    Science.gov (United States)

    Wolfe, Mary M; Davis, James W; Parks, Steven N

    2011-02-01

    Deep neck infections are potentially life-threatening conditions because of airway compromise. Management requires early recognition, antibiotics, surgical drainage, and effective airway control. The Surgical Education and Self-Assessment Program 12 states that awake tracheostomy is the treatment of choice for these patients. With advanced airway control techniques such as retrograde intubation, GlideScope, and fiberoptic intubation, surgical airway is not required. A retrospective analysis of all deep neck abscesses treated from December 1999 to July 2006 was performed. All patients who underwent urgent or emergent surgery for Ludwig angina and submental, submandibular, sublingual, and parapharyngeal abscesses (Current Procedural Terminology codes 41015, 41016, 41017, 42320, and 42725) were included in our review. Charts were studied for age, presence of true Ludwig angina, presence of airway compromise, airway management, morbidity/mortality, and the requirement for surgical airway. Of 29 patients, 6 (20%) had symptoms consistent with true Ludwig angina. Nineteen (65.5%) had evidence of airway compromise. Eight (42%) of these 19 patients required advanced airway control techniques. No patient required a surgical airway, and no mortality resulted from airway compromise. Advance airway control techniques were required more often in patients with airway compromise (P Ludwig angina and deep neck abscesses requires good clinical judgment. Patients with deep neck infections and symptoms of airway compromise may be safely managed with advanced airway control techniques. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Modeling the afferent dynamics of the baroreflex control system.

    Directory of Open Access Journals (Sweden)

    Adam Mahdi

    Full Text Available In this study we develop a modeling framework for predicting baroreceptor firing rate as a function of blood pressure. We test models within this framework both quantitatively and qualitatively using data from rats. The models describe three components: arterial wall deformation, stimulation of mechanoreceptors located in the BR nerve-endings, and modulation of the action potential frequency. The three sub-systems are modeled individually following well-established biological principles. The first submodel, predicting arterial wall deformation, uses blood pressure as an input and outputs circumferential strain. The mechanoreceptor stimulation model, uses circumferential strain as an input, predicting receptor deformation as an output. Finally, the neural model takes receptor deformation as an input predicting the BR firing rate as an output. Our results show that nonlinear dependence of firing rate on pressure can be accounted for by taking into account the nonlinear elastic properties of the artery wall. This was observed when testing the models using multiple experiments with a single set of parameters. We find that to model the response to a square pressure stimulus, giving rise to post-excitatory depression, it is necessary to include an integrate-and-fire model, which allows the firing rate to cease when the stimulus falls below a given threshold. We show that our modeling framework in combination with sensitivity analysis and parameter estimation can be used to test and compare models. Finally, we demonstrate that our preferred model can exhibit all known dynamics and that it is advantageous to combine qualitative and quantitative analysis methods.

  6. Suppression of food intake by GI fatty acid infusions: roles of celiac vagal afferents and cholecystokinin.

    Science.gov (United States)

    Cox, James E; Kelm, Gary R; Meller, Stephen T; Randich, Alan

    2004-08-01

    We have found that jejunal infusions of long-chain fatty acids, linoleic acid (LA) and oleic acid (OA), and gastric infusions of a fatty acid ethyl ester, ethyl oleate (EO), produce long-lasting suppression of total caloric intake. This effect is not seen in response to jejunal infusions of medium-chain fatty acids or medium- or long-chain triglycerides. Multiunit recordings have shown that intestinal infusions of LA or OA strongly activate celiac vagal afferents. Truncal vagotomy (TVX) and selective celiac-branch vagotomy (CVX) are equally effective in attenuating, but not eliminating, suppression of food intake by LA and EO. These outcomes suggest that intraintestinal fatty acids reduce intake by activation of vagal mechanisms, critically involving afferent fibers within the celiac branches, as well as unidentified nonvagal mechanisms. The role of cholecystokinin (CCK) in mediating the activation of celiac vagal afferents is suggested by studies showing that (1) inhibition of food intake by CCK-8 administration is attenuated after CVX but robust after celiac-spared vagotomy (CSV), (2) multiunit activity of celiac vagal afferents is increased by CCK-8 administration, and (3) activation of celiac fibers by intestinal LA infusion is severely attenuated by the CCK(A) antagonist lorglumide.

  7. A Fuzzy Controller for Movement Stabilization Using Afferent Control: Controller Synthesis and Simulation.

    Science.gov (United States)

    Khodadadi, Zahra; Kobravi, Hamid R; Majd, Milad F

    2017-01-01

    Stimulation of spinal sensorimotor circuits can improve motor control in animal models and humans with spinal cord injury (SCI). More recent evidence suggests that the stimulation increases the level of excitability in the spinal circuits, activates central pattern generators, and it is also able to recruit distinctive afferent pathways connected to specific sensorimotor circuits. In addition, the stimulation generates well-defined responses in leg muscles after each pulse. The problem is that in most of the neuromodulation devices, electrical stimulation parameters are regulated manually and stay constant during movement. Such a technique is likely suboptimal to intercede maximum therapeutic effects in patients. Therefore, in this article, a fuzzy controller has been designed to control limb kinematics during locomotion using the afferent control in a neuromechanical model without supraspinal drive simulating post-SCI situation. The proposed controller automatically tunes the weights of group Ia afferent inputs of the spinal cord to reset the phase appropriately during the reaction to an external perturbation. The kinematic motion data and weights of group Ia afferent inputs were the input and output of the controller, respectively. Simulation results showed the acceptable performance of the controller to establish adaptive locomotion against the perturbing forces based on the phase resetting of the walking rhythm.

  8. Afferent loop syndrome - a case report; Sindrome da alca aferente - relato de um caso

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Ana Karina Nascimento; Pinheiro, Marco Antonio Lopes; Galvao, Cristine Norwig [Fundacao Pio XII - Hospital do Cancer de Barretos, SP (Brazil)

    2000-02-01

    The afferent loop syndrome occurs in patients with previous gastric surgery for tumor, when there is anastomotic edema, use of inappropriate reconstruction technique for gastro jejunostomy or recurrent gastric cancer. Complaints such jaundice, intermittent abdominal distension associated with pain, and vomiting should be investigated in order to rule out this syndrome. (author)

  9. Episodic release of renin from single isolated superfused rat afferent arterioles

    DEFF Research Database (Denmark)

    Skøtt, O

    1986-01-01

    Doubts have been raised about the involvement of an exocytotic event in the renin release process. This motivated the development of a technique which permitted the study of renin release from one single superfused rat afferent arteriole with a time resolution of 20 seconds. By using this technique...

  10. Chloride is essential for contraction of afferent arterioles after agonists and potassium

    DEFF Research Database (Denmark)

    Jensen, B L; Ellekvist, Peter; Skøtt, O

    1997-01-01

    A depolarizing chloride efflux has been suggested to activate voltage-dependent calcium channels in renal afferent arteriolar smooth muscle cells in response to vasoconstrictors. To test this proposal, rabbit afferent arterioles were microperfused, and the contractile dose responses to norepineph......A depolarizing chloride efflux has been suggested to activate voltage-dependent calcium channels in renal afferent arteriolar smooth muscle cells in response to vasoconstrictors. To test this proposal, rabbit afferent arterioles were microperfused, and the contractile dose responses...... to norepinephrine, angiotensin II (ANG II), and potassium were measured after chloride depletion and compared with controls. Chloride depletion did not change arteriolar diameters, but the response to norepinephrine was markedly reduced when chloride was substituted with gluconate (n = 6) or isethionate (n = 6......). Reintroduction of chloride fully restored the sensitivity to norepinephrine. Contractions after ANG II and potassium were totally abolished in the absence of chloride (n = 6). In additional experiments (n = 7), the arteriolar contraction to 100 mM potassium was abolished only 1 min after removal of extracellular...

  11. Functional analysis of ultra high information rates conveyed by rat vibrissal primary afferents

    NARCIS (Netherlands)

    A.M. Chagas (André); L. Theis (Lucas); B. Sengupta (Biswa); M.C. Stüttgen (Maik); M. Bethge (Matthias); C. Schwarz (Cornelius)

    2013-01-01

    textabstractSensory receptors determine the type and the quantity of information available for perception. Here, we quantified and characterized the information transferred by primary afferents in the rat whisker system using neural system identification. Quantification of "how much" information is

  12. Regional anesthesia in difficult airway: The quest for a solution continues.

    Science.gov (United States)

    Khetarpal, Ranjana; Chatrath, Veena; Dhawan, Akshay; Attri, Joginder Pal

    2016-01-01

    Difficult airway, a scenario with potentially life threatening outcome, is routinely encountered by an anesthesiologist leaving him with the dilemma of whether to use regional anesthesia (RA) or general anesthesia. Our study aims to look into this problem. The literature search was performed in the Google, PubMed, and Medscape using key words "regional anesthesia, difficult airway, pregnancy, ventilation, intubation, epidural anesthesia, nerve blocks." More than 38 free full articles and books published from the year 1987 to 2014 were retrieved and studied. At first sight, RA may appear to offer an ideal solution as it helps to avoid the problem of difficult airway. However, the possibility of a total spinal block, failed or incomplete RA, local anesthetic toxicity or unforeseen surgical complication may make it imperative that the airway is secured. The correct decision can only be made by the anesthetist when all the relevant clinical information is taken into account. It is also important to ensure that before considering RA in a patient of difficult airway, an anesthesiologist must have a preformulated strategy for intubation.

  13. Overview of the Cranial Nerves

    Science.gov (United States)

    ... to the back). Viewing the Cranial Nerves Twelve pairs of cranial nerves emerge from the underside of the brain, ... eye movement. Eye movement is controlled by 3 pairs of muscles. These muscles move the eye up and down, right and ... nerve 4th cranial nerve 6th ...

  14. Large Extremity Peripheral Nerve Repair

    Science.gov (United States)

    2016-12-01

    rodents as a function of time after surgery. As predicted, those animals in the negative control group (no repair following nerve deficit injury ...80% of penetrating injuries being associated with peripheral nerve damage, typically involve large segmental nerve deficits. Standard repair uses...technology for repair of peripheral nerve injuries involving significant neural deficit with improved functional outcomes for the wounded warrior. The

  15. Evidence of the Primary Afferent Tracts Undergoing Neurodegeneration in Horses With Equine Degenerative Myeloencephalopathy Based on Calretinin Immunohistochemical Localization.

    Science.gov (United States)

    Finno, C J; Valberg, S J; Shivers, J; D'Almeida, E; Armién, A G

    2016-01-01

    Equine degenerative myeloencephalopathy (EDM) is characterized by a symmetric general proprioceptive ataxia in young horses, and is likely underdiagnosed for 2 reasons: first, clinical signs overlap those of cervical vertebral compressive myelopathy; second, histologic lesions--including axonal spheroids in specific tracts of the somatosensory and motor systems--may be subtle. The purpose of this study was (1) to utilize immunohistochemical (IHC) markers to trace axons in the spinocuneocerebellar, dorsal column-medial lemniscal, and dorsospinocerebellar tracts in healthy horses and (2) to determine the IHC staining characteristics of the neurons and degenerated axons along the somatosensory tracts in EDM-affected horses. Examination of brain, spinal cord, and nerves was performed on 2 age-matched control horses, 3 EDM-affected horses, and 2 age-matched disease-control horses via IHC for calbindin, vesicular glutamate transporter 2, parvalbumin, calretinin, glutamic acid decarboxylase, and glial fibrillary acidic protein. Primary afferent axons of the spinocuneocerebellar, dorsal column-medial lemniscal, and dorsospinocerebellar tracts were successfully traced with calretinin. Calretinin-positive cell bodies were identified in a subset of neurons in the dorsal root ganglia, suggesting that calretinin IHC could be used to trace axonal projections from these cell bodies. Calretinin-immunoreactive spheroids were present in EDM-affected horses within the nuclei cuneatus medialis, cuneatus lateralis, and thoracicus. Neurons within those nuclei were calretinin negative. Cell bodies of degenerated axons in EDM-affected horses are likely located in the dorsal root ganglia. These findings support the role of sensory axonal degeneration in the pathogenesis of EDM and provide a method to highlight tracts with axonal spheroids to aid in the diagnosis of this neurodegenerative disease. © The Author(s) 2015.

  16. Anaesthesia and subglottic airway obstruction

    African Journals Online (AJOL)

    Keywords: shared airway; jet ventilation; TIVA/TCI; laser excision; monitoring. Abstract. In this article, we describe the anaesthetic ... (Submitted: 2009-07-14, Accepted: 2010-10-04). S Afr J Anaesth Analg 2011;17(2):182-184 ... Jet ventilation and TCI/TIVA (total intravenous anaesthesia) are our techniques of choice for ...

  17. allergy, asthma airway and anaphylaxis

    African Journals Online (AJOL)

    The perioperative preparation of children presenting for surgery aims to identify medical problems that might influence the outcome and to institute management strategies to reduce those risks. Respiratory and airway complications remain the most significant cause of morbidity and mortality in modern paediatric ...

  18. Pharyngeal airway changes following mandibular setback surgery

    Directory of Open Access Journals (Sweden)

    Babu Ramesh

    2005-01-01

    Full Text Available Treatment of dentofacial deformities with jaw osteotomies has an effect on airway anatomy and therefore mandibular setback surgery has the potential to diminish airway size. The purpose of this study was to evaluate the effect of mandibular setback surgery on airway size. 8 consecutive patients were examined prospectively. All patients underwent mandibular setback surgery. Cephalometric analysis was performed preoperatively and 3 months post operatively with particular attention to pharyngeal airway changes. Pharyngeal airway size decreased considerably in all, patients thus predisposing to development of obstructive sleep apnea. Therefore, large anteroposterior discrepancies should be corrected by combined maxillary and mandibular osteotomies.

  19. Radial to axillary nerve transfer.

    Science.gov (United States)

    Vanaclocha, Vicente; Herrera, Juan Manuel; Rivera-Paz, Marlon; Martínez-Gómez, Deborah; Vanaclocha, Leyre

    2018-01-01

    Axillary nerve injury is common after brachial plexus injuries, particularly with shoulder luxation. Nerve grafting is the traditional procedure for postganglionic injuries. Nerve transfer is emerging as a viable option particularly in late referrals. At the proximal arm the radial and axillary nerves lie close by. Sacrificing one of the triceps muscle nerve branches induces little negative consequences. Transferring the long head of the triceps nerve branch is a good option to recover axillary nerve function. The surgical technique is presented in a video, stressing the steps to achieve a successful result. The video can be found here: https://youtu.be/WbVbpMuPxIE .

  20. Diabetes and nerve damage

    Science.gov (United States)

    Diabetic neuropathy; Diabetes - neuropathy; Diabetes - peripheral neuropathy ... In people with diabetes, the body's nerves can be damaged by decreased blood flow and a high blood sugar level. This condition is ...

  1. Optic Nerve Drusen

    Science.gov (United States)

    ... nerve. Ocular ultrasound, CT scan and/or fundus photography can also aid in the diagnosis. Drusen can ... Medical Disclaimer Search Site ▶ AAPOS Headquarters 655 Beach Street San Francisco, CA 94109-1336 Phone: (415) 561- ...

  2. Vagus Nerve Stimulation

    Science.gov (United States)

    ... you do certain activities such as public speaking, singing or exercising, or when you're eating if ... of life. Research is still mixed on the benefits of vagus nerve stimulation for the treatment of ...

  3. Laryngeal nerve damage

    Science.gov (United States)

    Symptoms include: Difficulty speaking Difficulty swallowing Hoarseness Injury to the left and right laryngeal nerves at the same time can cause a breathing problem. This can be an urgent medical problem.

  4. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    la Cour, M; Kiilgaard, Jens Folke; Eysteinsson, T

    2000-01-01

    To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide....

  5. Degenerative Nerve Diseases

    Science.gov (United States)

    Degenerative nerve diseases affect many of your body's activities, such as balance, movement, talking, breathing, and heart function. Many of these diseases are genetic. Sometimes the cause is a medical ...

  6. Hyposensitivity of C-fiber afferents at the distal extremities as an indicator of early stages diabetic bladder dysfunction in type 2 diabetic women.

    Directory of Open Access Journals (Sweden)

    Wei-Chia Lee

    Full Text Available PURPOSE: To investigate the relationship between distal symmetric peripheral neuropathy and early stages of autonomic bladder dysfunction in type 2 diabetic women. MATERIALS AND METHODS: A total of 137 diabetic women with minimal coexisting confounders of voiding dysfunction followed at a diabetes clinic were subject to the following evaluations: current perception threshold (CPT tests on myelinated and unmyelinated nerves at the big toe for peroneal nerve and middle finger for median nerve, uroflowmetry, post-void residual urine volume, and overactive bladder (OAB symptom score questionnaire. Patients presenting with voiding difficulty also underwent urodynamic studies and intravesical CPT tests. RESULTS: Based on the OAB symptom score and urodynamic studies, 19% of diabetic women had the OAB syndrome while 24.8% had unrecognized urodynamic bladder dysfunction (UBD. The OAB group had a significantly greater mean 5 Hz CPT test value at the big toe by comparison to those without OAB. When compared to diabetic women without UBD, those with UBD showed greater mean 5 Hz CPT test values at the middle finger and big toe. The diabetic women categorized as C-fiber hyposensitivity at the middle finger or big toe by using CPT test also had higher odds ratios of UBD. Among diabetic women with UBD, the 5 Hz CPT test values at the big toe and middle finger were significantly associated with intravesical 5 Hz CPT test values. CONCLUSIONS: Using electrophysiological evidence, our study revealed that hyposensitivity of unmyelinated C fiber afferents at the distal extremities is an indicator of early stages diabetic bladder dysfunction in type 2 diabetic women. The C fiber dysfunction at the distal extremities seems concurrent with vesical C-fiber neuropathy and may be a sentinel for developing early diabetic bladder dysfunction among female patients.

  7. Selective plasticity of primary afferent innervation to the dorsal horn and autonomic nuclei following lumbosacral ventral root avulsion and reimplantation in long term studies.

    Science.gov (United States)

    Wu, Lisa; Wu, Jun; Chang, Huiyi H; Havton, Leif A

    2012-02-01

    Previous studies involving injuries to the nerves of the cauda equina and the conus medullaris have shown that lumbosacral ventral root avulsion in rat models results in denervation and dysfunction of the lower urinary tract, retrograde and progressive cell death of the axotomized motor and parasympathetic neurons, as well as the emergence of neuropathic pain. Root reimplantation has also been shown to ameliorate several of these responses, but experiments thus far have been limited to studying the effects of lesion and reimplantation local to the lumbosacral region. Here, we have expanded the region of investigation after lumbosacral ventral root avulsion and reimplantation to include the thoracolumbar sympathetic region of the spinal cord. Using a retrograde tracer injected into the major pelvic ganglion, we were able to define the levels of the spinal cord that contain sympathetic preganglionic neurons innervating the lower urinary tract. We have conducted studies on the effects of the lumbosacral ventral root avulsion and reimplantation models on the afferent innervation of the dorsal horn and autonomic nuclei at both thoracolumbar and lumbosacral levels through immunohistochemistry for the markers calcitonin gene-related peptide (CGRP) and vesicular glutamate transporter 1 (VGLUT1). Surprisingly, our experiments reveal a selective and significant decrease of CGRP-positive innervation in the dorsal horn at thoracolumbar levels that is partially restored with root reimplantation. However, no similar changes were detected at the lumbosacral levels despite the injury and repair targeting efferent neurons, and being performed at the lumbosacral levels. Despite the changes evident in the thoracolumbar dorsal horn, we find no changes in afferent innervation of the autonomic nuclei at either sympathetic or parasympathetic segmental levels by CGRP or VGLUT1. We conclude that even remote, efferent root injuries and repair procedures can have an effect on remote and non

  8. NMDA receptors control vagal afferent excitability in the nucleus of the solitary tract.

    Science.gov (United States)

    Vance, Katie M; Rogers, Richard C; Hermann, Gerlinda E

    2015-01-21

    Previous behavioral studies have demonstrated that presynaptic N-methyl-d-aspartate (NMDA) receptors expressed on vagal afferent terminals are involved in food intake and satiety. Therefore, using in vitro live cell calcium imaging of prelabeled rat hindbrain slices, we characterized which NMDA receptor GluN2 subunits may regulate vagal afferent activity. The nonselective NMDA receptor antagonist d,l-2-amino-5-phosphonopentanoic acid (d,l-AP5) significantly inhibited vagal terminal calcium influx, while the excitatory amino acid reuptake inhibitor d,l-threo-β-benzyloxyaspartic acid (TBOA), significantly increased terminal calcium levels following pharmacological stimulation with ATP. Subunit-specific NMDA receptor antagonists and potentiators were used to identify which GluN2 subunits mediate the NMDA receptor response on the vagal afferent terminals. The GluN2B-selective antagonist, ifenprodil, selectively reduced vagal calcium influx with stimulation compared to the time control. The GluN2A-selective antagonist, 3-chloro-4-fluoro-N-[4-[[2-(phenylcarbonyl)hydrazino]carbonyl] benzyl]benzenesulfonamide (TCN 201) produced smaller but not statistically significant effects. Furthermore, the GluN2A/B-selective potentiator (pregnenolone sulfate) and the GluN2C/D-selective potentiator [(3-chlorophenyl)(6,7-dimethoxy-1-((4-methoxyphenoxy)methyl)-3,4-dihydroisoquinolin-2(1H)-yl)methanone; (CIQ)] enhanced vagal afferent calcium influx during stimulation. These data suggest that presynaptic NMDA receptors with GluN2B, GluN2C, and GluN2D subunits may predominantly control vagal afferent excitability in the nucleus of the solitary tract. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Surgical airway in emergency department intubation.

    Science.gov (United States)

    Reid, Lindsay A; Dunn, Mark; Mckeown, Dermot W; Oglesby, Angela J

    2011-06-01

    To determine the frequency of and primary indication for surgical airway during emergency department intubation. Prospectively collected data from all intubations performed in the emergency department from January 1999 to July 2007 were analysed to ascertain the frequency of surgical airway access. Original data were collected on a structured proforma, entered into a regional database and analysed. Patient records were then reviewed to determine the primary indication for a surgical airway. Emergency department intubation was undertaken in 2524 patients. Of these, only five patients (0.2%) required a surgical airway. The most common indication for a surgical airway was trauma in four of the five patients. Two patients had attempted rapid sequence induction before surgical airway. Two patients had gaseous inductions and one patient received no drugs. In all five patients, surgical airway was performed secondary to failed endotracheal intubation attempt(s) and was never the primary technique used. In our emergency department, surgical airway is an uncommon procedure. The rate of 0.2% is significantly lower than rates quoted in other studies. The most common indication for surgical airway was severe facial or neck trauma. Our emergency department has a joint protocol for emergency intubation agreed by the Departments of Emergency Medicine, Anaesthesia and Critical Care at the Edinburgh Royal Infirmary. We believe that the low surgical airway rate is secondary to this collaborative approach. The identified low rate of emergency department surgical airway has implications for training and maintenance of skills for emergency medicine trainees and physicians.

  10. Effect of Bronchial Thermoplasty on Airway Closure

    Directory of Open Access Journals (Sweden)

    Robert Brown

    2007-01-01

    Full Text Available Background Bronchial Thermoplasty, a procedure that applies thermal energy to the airway wall has been shown to impair the ability of airway to contract in response to methacholine chloride (Mch. The technique has been advocated as an alternative treatment for asthma that may permanently limit airway narrowing. In previous experimental studies in dogs and humans, it was shown that those airways treated with bronchial thermoplasty had significant impairment of Mch responsiveness. Methods In the present study, we investigated the ability of canine airways to close completely with very high concentrations of Mch after bronchial thermoplasty. Bronchial thermoplasty was performed on dogs using the Alair System, comprising a low power RF controller and a basket catheter with four electrodes. A local atomization of Mch agonist was delivered directly to the epithelium of the same airway locations with repeated challenges. Airway size was measured with computed tomography, and closure was considered to occur in any airway where the lumen fell below the resolution of the scanner (< 1 mm. Results Our results show that, while treated airways still have the capacity to close at very high doses of Mch, this ability is seriously impaired after treatment, requiring much higher doses. Conclusions Bronchial thermoplasty as currently applied seems to simply shift the entire dose response curve toward increasing airway size. Thus, this procedure simply serves to minimize the ability of airways to narrow under any level of stimulation.

  11. Airway malacia in children with achondroplasia.

    Science.gov (United States)

    Dessoffy, Kimberly E; Modaff, Peggy; Pauli, Richard M

    2014-02-01

    This study was undertaken to assess the frequency of airway malacia in infants and young children with achondroplasia, a population well known to be at risk for a variety of respiratory problems. We also wished to evaluate what, if any, contribution airway malacia makes to the complex respiratory issues that may be present in those with achondroplasia. Retrospective chart review of all infants and young children with achondroplasia who were assessed through the Midwest Regional Bone Dysplasia Clinics from 1985 through 2012 (n = 236) was completed. Records of comprehensive clinical examinations, polysomnographic assessments, and airway visualization were reviewed and abstracted using a data collection form. Analyses were completed comparing the group with and those without evidence for airway malacia. Thirteen of 236 patients (5.5%) were found to have airway malacia. Most of those affected had lower airway involvement (9/13). The presence of airway malacia was correlated with an increased occurrence of obstructive sleep apnea as well as need for oxygen supplementation, airway surgeries and tracheostomy placement. Although estimates of the frequency of airway malacia in the general population are limited, its frequency in children with achondroplasia appears to be much higher than any published general population estimate. The presence of airway malacia appears to confound other breathing abnormalities in this population and results in the need for more invasive airway treatments. © 2013 Wiley Periodicals, Inc.

  12. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    la Cour, M; Kiilgaard, Jens Folke; Eysteinsson, T

    2000-01-01

    To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide.......To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide....

  13. Conjoined lumbosacral nerve roots

    Directory of Open Access Journals (Sweden)

    Atila Yılmaz

    2012-03-01

    Full Text Available Lumbosacral nerve root anomalies are a rare group ofcongenital anatomical anomalies. Various types of anomaliesof the lumbosacral nerve roots have been documentedin the available international literature. Ttheseanomalies may consist of a bifid, conjoined structure, ofa transverse course or of a characteristic anastomizedappearance. Firstly described as an incidental findingduring autopsies or surgical procedures performed forlumbar disk herniations and often asymptomatic, lumbosacralnerve root anomalies have been more frequentlydescribed in the last years due to the advances made inradiological diagnosis.

  14. Analysis of airways in computed tomography

    DEFF Research Database (Denmark)

    Petersen, Jens

    Chronic Obstructive Pulmonary Disease (COPD) is major cause of death and disability world-wide. It affects lung function through destruction of lung tissue known as emphysema and inflammation of airways, leading to thickened airway walls and narrowed airway lumen. Computed Tomography (CT) imaging...... have become the standard with which to assess emphysema extent but airway abnormalities have so far been more challenging to quantify. Automated methods for analysis are indispensable as the visible airway tree in a CT scan can include several hundreds of individual branches. However, automation...... the Danish Lung Cancer Screening Trial. This includes methods for extracting airway surfaces from the images and ways of achieving comparable measurements in airway branches through matching and anatomical labelling. The methods were used to study effects of differences in inspiration level at the time...

  15. Bronchial thermoplasty and the role of airway smooth muscle: are we on the right direction?

    Directory of Open Access Journals (Sweden)

    Menzella F

    2017-09-01

    Full Text Available Francesco Menzella,1 Mirco Lusuardi,2 Carla Galeone,1 Nicola Facciolongo1 1Department of Medical Specialties, Pneumology Unit, IRCCS – Arcispedale Santa Maria Nuova, Reggio Emilia, 2Unit of Respiratory Rehabilitation, AUSL Reggio Emilia, S Sebastiano Hospital, Correggio, Italy Abstract: Asthma is characterized by inflammation of the airways that includes eosinophils, basal membrane thickening, epithelial sloughing, vascular changes, smooth muscle hypertrophy and hyperplasia, and mucous gland hyperplasia. Recently, there have been studies on the role of hypersensitivity and inflammation in asthma, but the role of bronchial smooth muscle remains unclear. Bronchial thermoplasty is an endoscopic procedure that is approved by the US Food and Drug Administration (FDA for the treatment of severe refractory asthma, based on the local delivery of radio frequency at 65°C to the airways, with the aim of controlling bronchospasm through a reduction of airway smooth muscle (ASM. Several recent studies have shown significant improvement in clinical outcomes of bronchial thermoplasty for asthma, including symptom control, reduction in exacerbation and hospitalization rates, improved quality of life, and reduction in number of working days or school days lost due to asthma. Data from these recent studies have shown reduction in ASM following bronchial thermoplasty and changes in inflammation patterns. It has also been argued that bronchial thermoplasty may have modulating effects on neuroendocrine epithelial cells, bronchial nerve endings, TRPV1 nerve receptors, and type-C unmyelinated fibers in the bronchial mucosa. This may involve interrupting the central and local reflexes responsible for the activation of bronchospasm in the presence of bronchial hyperreactivity. Several questions remain regarding the use of bronchial thermoplasty, mechanism of action, selection of appropriate patients, and long-term effects. In this review, the role of ASM in the

  16. Serotonin, dopamine and noradrenaline adjust actions of myelinated afferents via modulation of presynaptic inhibition in the mouse spinal cord.

    Science.gov (United States)

    García-Ramírez, David L; Calvo, Jorge R; Hochman, Shawn; Quevedo, Jorge N

    2014-01-01

    Gain control of primary afferent neurotransmission at their intraspinal terminals occurs by several mechanisms including primary afferent depolarization (PAD). PAD produces presynaptic inhibition via a reduction in transmitter release. While it is known that descending monoaminergic pathways complexly regulate sensory processing, the extent these actions include modulation of afferent-evoked PAD remains uncertain. We investigated the effects of serotonin (5HT), dopamine (DA) and noradrenaline (NA) on afferent transmission and PAD. Responses were evoked by stimulation of myelinated hindlimb cutaneous and muscle afferents in the isolated neonatal mouse spinal cord. Monosynaptic responses were examined in the deep dorsal horn either as population excitatory synaptic responses (recorded as extracellular field potentials; EFPs) or intracellular excitatory postsynaptic currents (EPSCs). The magnitude of PAD generated intraspinally was estimated from electrotonically back-propagating dorsal root potentials (DRPs) recorded on lumbar dorsal roots. 5HT depressed the DRP by 76%. Monosynaptic actions were similarly depressed by 5HT (EFPs 54%; EPSCs 75%) but with a slower time course. This suggests that depression of monosynaptic EFPs and DRPs occurs by independent mechanisms. DA and NA had similar depressant actions on DRPs but weaker effects on EFPs. IC50 values for DRP depression were 0.6, 0.8 and 1.0 µM for 5HT, DA and NA, respectively. Depression of DRPs by monoamines was nearly-identical in both muscle and cutaneous afferent-evoked responses, supporting a global modulation of the multimodal afferents stimulated. 5HT, DA and NA produced no change in the compound antidromic potentials evoked by intraspinal microstimulation indicating that depression of the DRP is unrelated to direct changes in the excitability of intraspinal afferent fibers, but due to metabotropic receptor activation. In summary, both myelinated afferent-evoked DRPs and monosynaptic transmission in the

  17. Serotonin, dopamine and noradrenaline adjust actions of myelinated afferents via modulation of presynaptic inhibition in the mouse spinal cord.

    Directory of Open Access Journals (Sweden)

    David L García-Ramírez

    Full Text Available Gain control of primary afferent neurotransmission at their intraspinal terminals occurs by several mechanisms including primary afferent depolarization (PAD. PAD produces presynaptic inhibition via a reduction in transmitter release. While it is known that descending monoaminergic pathways complexly regulate sensory processing, the extent these actions include modulation of afferent-evoked PAD remains uncertain. We investigated the effects of serotonin (5HT, dopamine (DA and noradrenaline (NA on afferent transmission and PAD. Responses were evoked by stimulation of myelinated hindlimb cutaneous and muscle afferents in the isolated neonatal mouse spinal cord. Monosynaptic responses were examined in the deep dorsal horn either as population excitatory synaptic responses (recorded as extracellular field potentials; EFPs or intracellular excitatory postsynaptic currents (EPSCs. The magnitude of PAD generated intraspinally was estimated from electrotonically back-propagating dorsal root potentials (DRPs recorded on lumbar dorsal roots. 5HT depressed the DRP by 76%. Monosynaptic actions were similarly depressed by 5HT (EFPs 54%; EPSCs 75% but with a slower time course. This suggests that depression of monosynaptic EFPs and DRPs occurs by independent mechanisms. DA and NA had similar depressant actions on DRPs but weaker effects on EFPs. IC50 values for DRP depression were 0.6, 0.8 and 1.0 µM for 5HT, DA and NA, respectively. Depression of DRPs by monoamines was nearly-identical in both muscle and cutaneous afferent-evoked responses, supporting a global modulation of the multimodal afferents stimulated. 5HT, DA and NA produced no change in the compound antidromic potentials evoked by intraspinal microstimulation indicating that depression of the DRP is unrelated to direct changes in the excitability of intraspinal afferent fibers, but due to metabotropic receptor activation. In summary, both myelinated afferent-evoked DRPs and monosynaptic

  18. Regeneration of Optic Nerve

    Directory of Open Access Journals (Sweden)

    Kwok-Fai So

    2011-05-01

    Full Text Available The optic nerve is part of the central nervous system (CNS and has a structure similar to other CNS tracts. The axons that form the optic nerve originate in the ganglion cell layer of the retina and extend through the optic tract. As a tissue, the optic nerve has the same organization as the white matter of the brain in regard to its glia. There are three types of glial cells: Oligodendrocytes, astrocytes, and microglia. Little structural and functional regeneration of the CNS takes place spontaneously following injury in adult mammals. In contrast, the ability of the mammalian peripheral nervous system (PNS to regenerate axons after injury is well documented. A number of factors are involved in the lack of CNS regeneration, including: (i the response of neuronal cell bodies against the damage; (ii myelin-mediated inhibition by oligodendrocytes; (iii glial scarring, by astrocytes; (iv macrophage infiltration; and (v insufficient trophic factor support. The fundamental difference in the regenerative capacity between CNS and PNS neuronal cell bodies has been the subject of intensive research. In the CNS the target normally conveys a retrograde trophic signal to the cell body. CNS neurons die because of trophic deprivation. Damage to the optic nerve disconnects the neuronal cell body from its target-derived trophic peptides, leading to the death of retinal ganglion cells. Furthermore, the axontomized neurons become less responsive to the peptide trophic signals they do receive. On the other hand, adult PNS neurons are intrinsically responsive to neurotrophic factors and do not lose trophic responsiveness after axotomy. In this talk different strategies to promote optic-nerve regeneration in adult mammals are reviewed. Much work is still needed to resolve many issues. This is a very important area of neuroregeneration and neuroprotection, as currently there is no cure after traumatic optic nerve injury or retinal disease such as glaucoma, which

  19. Effect of Bronchial Thermoplasty on Airway Closure.

    Science.gov (United States)

    Brown, Robert; Wizeman, William; Danek, Christopher; Mitzner, Wayne

    2007-10-12

    BACKGROUND: Bronchial Thermoplasty, a procedure that applies thermal energy to the airway wall has been shown to impair the ability of airway to contract in response to methacholine chloride (Mch). The technique has been advocated as an alternative treatment for asthma that may permanently limit airway narrowing. In previous experimental studies in dogs and humans, it was shown that those airways treated with bronchial thermoplasty had significant impairment of Mch responsiveness. METHODS: In the present study, we investigated the ability of canine airways to close completely with very high concentrations of Mch after bronchial thermoplasty. Bronchial thermoplasty was performed on dogs using the Alair System, comprising a low power RF controller and a basket catheter with four electrodes. A local atomization of Mch agonist was delivered directly to the epithelium of the same airway locations with repeated challenges. Airway size was measured with computed tomography, and closure was considered to occur in any airway where the lumen fell below the resolution of the scanner (Bronchial thermoplasty as currently applied seems to simply shift the entire dose response curve toward increasing airway size. Thus, this procedure simply serves to minimize the ability of airways to narrow under any level of stimulation.

  20. Percutaneous Transhepatic Duodenal Drainage as an Alternative Approach in Afferent Loop Obstruction with Secondary Obstructive Jaundice in Recurrent Gastric Cancer

    International Nuclear Information System (INIS)

    Yao, N.-S.; Wu, C.-W.; Tiu, Chui-Mei; Liu, Jacqueline M.; Whang-Peng, Jacqueline; Chen, L.-T.

    1998-01-01

    Two cases are reported of chronic, partial afferent loop obstruction with resultant obstructive jaundice in recurrent gastric cancer. The diagnosis was made by characteristic clinical presentations, abdominal computed tomography, and cholescintigraphy. Percutaneous transhepatic duodenal drainage (PTDD) provided effective palliation for both afferent loop obstruction and biliary stasis. We conclude that cholescintigraphy is of value in making the diagnosis of partial afferent loop obstruction and in differentiating the cause of obstructive jaundice in such patients, and PTDD provides palliation for those patients in whom surgical intervention is not feasible

  1. Right hypoglossal nerve paralysis after tracheal intubation for aesthetic breast surgery

    Directory of Open Access Journals (Sweden)

    Sammy Al-Benna

    2013-01-01

    Full Text Available Aesthetic and functional complications caused by general anesthesia have been rarely described after aesthetic surgery. We report a case of unilateral right hypoglossal nerve paralysis following the use of a cuffed endotracheal airway in a 24-year-old woman undergoing aesthetic breast surgery. Neurological examination and magnetic resonance imaging of the head failed to provide additional insights into the cause of the nerve injury. Postoperatively, the patient was carefully monitored and made a full recovery within 2 weeks without any pharmacological treatment. The transient hypoglossal nerve paralysis seemed to be due to neuropraxia. In this patient, we postulate that the right hypoglossal nerve was compressed between the endotracheal tube cuff and the hyoid bone, which was inflated with 30 cm H 2 O. Patients undergoing aesthetic surgery must be appropriately and adequately informed that postoperative aesthetic and functional deficits can occur due to anesthesia as well as the surgery.

  2. Vestibular neuritis affects both superior and inferior vestibular nerves.

    Science.gov (United States)

    Taylor, Rachael L; McGarvie, Leigh A; Reid, Nicole; Young, Allison S; Halmagyi, G Michael; Welgampola, Miriam S

    2016-10-18

    To characterize the profiles of afferent dysfunction in a cross section of patients with acute vestibular neuritis using tests of otolith and semicircular canal function sensitive to each of the 5 vestibular end organs. Forty-three patients fulfilling clinical criteria for acute vestibular neuritis were recruited between 2010 and 2016 and studied within 10 days of symptom onset. Otolith function was evaluated with air-conducted cervical and bone-conducted ocular/vestibular evoked myogenic potentials and the subjective visual horizontal test. Canal-plane video head impulse tests (vHITs) assessed the function of each semicircular canal. Patterns of recovery were investigated in 16 patients retested after a 6- to 12-month follow-up period. Rates of horizontal canal (97.7%), anterior canal (90.7%), and utricular (72.1%) dysfunction were significantly higher than rates of posterior canal (39.5%) and saccular (39.0%) dysfunction (p vestibular nerve divisions; 18 patients (41.9%) had superior neuritis; and 1 patient (2.3%) had inferior neuritis. A test battery that included horizontal and posterior canal vHIT and the cervical/vestibular evoked myogenic potentials identified superior or inferior neuritis in all patients tested acutely. Eight of 16 patients who were retested at follow-up had recovered a normal vestibular evoked myogenic potential and vHIT profile. Acute vestibular neuritis most often affects both vestibular nerve divisions. The horizontal vHIT alone identifies superior nerve dysfunction in all patients with vestibular neuritis tested acutely, whereas both cervical/vestibular evoked myogenic potentials and posterior vHIT are necessary for diagnosing inferior vestibular nerve involvement. © 2016 American Academy of Neurology.

  3. Long-nerve grafts and nerve transfers demonstrate comparable outcomes for axillary nerve injuries.

    Science.gov (United States)

    Wolfe, Scott W; Johnsen, Parker H; Lee, Steve K; Feinberg, Joseph H

    2014-07-01

    To compare the functional and EMG outcomes of long-nerve grafts to nerve transfers for complete axillary nerve palsy. Over a 10-year period at a single institution, 14 patients with axillary nerve palsy were treated with long-nerve grafts and 24 patients were treated with triceps-to-axillary nerve transfers by the same surgeon (S.W.W.). Data were collected prospectively at regular intervals, beginning before surgery and continuing up to 11 years after surgery. Prior to intervention, all patients demonstrated EMG evidence of complete denervation of the deltoid. Deltoid recovery (Medical Research Council [MRC] grade), shoulder abduction (°), improvement in shoulder abduction (°), and EMG evidence of deltoid reinnervation were compared between cohorts. There were no significant differences between the long-nerve graft cohort and the nerve transfer cohort with respect to postoperative range of motion, deltoid recovery, improvement in shoulder abduction, or EMG evidence of deltoid reinnervation. These data demonstrate that outcomes of long-nerve grafts for axillary nerve palsy are comparable with those of modern nerve transfers and question a widely held belief that long-nerve grafts do poorly. When healthy donor roots or trunks are available, long-nerve grafts should not be overlooked as an effective intervention for the treatment of axillary nerve injuries in adults with brachial plexus injuries. Therapeutic III. Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  4. Airway injury during emergency transcutaneous airway access: a comparison at cricothyroid and tracheal sites.

    LENUS (Irish Health Repository)

    Salah, Nazar

    2009-12-01

    Oxygenation via the cricothyroid membrane (CTM) may be required in emergencies, but inadvertent tracheal cannulation may occur. In this study, we compared airway injury between the tracheal and CTM sites using different techniques for airway access.

  5. 75 FR 13079 - Action Affecting Export Privileges; MAHAN AIRWAYS; Mahan Airways, Mahan Tower, No. 21, Azadegan...

    Science.gov (United States)

    2010-03-18

    ... Regulations and TDO, a United Kingdom court found Mahan Airways in contempt of court on February 1, 2010, for... contempt finding against Mahan Airways in the U.K. litigation, which I understand is still ongoing. I note...

  6. Mediators on human airway smooth muscle.

    Science.gov (United States)

    Armour, C; Johnson, P; Anticevich, S; Ammit, A; McKay, K; Hughes, M; Black, J

    1997-01-01

    1. Bronchial hyperresponsiveness in asthma may be due to several abnormalities, but must include alterations in the airway smooth muscle responsiveness and/or volume. 2. Increased responsiveness of airway smooth muscle in vitro can be induced by certain inflammatory cell products and by induction of sensitization (atopy). 3. Increased airway smooth muscle growth can also be induced by inflammatory cell products and atopic serum. 4. Mast cell numbers are increased in the airways of asthmatics and, in our studies, in airway smooth muscle that is sensitized and hyperresponsive. 5. We propose that there is a relationship between mast cells and airway smooth muscle cells which, once an allergic process has been initiated, results in the development of critical features in the lungs in asthma.

  7. Extraction of airways from CT (EXACT’09)

    DEFF Research Database (Denmark)

    Lo, Pechin Chien Pau; Ginneken, Bram van; Reinhardt, Joseph M.

    2012-01-01

    This paper describes a framework for establishing a reference airway tree segmentation, which was used to quantitatively evaluate 15 different airway tree extraction algorithms in a standardized manner. Because of the sheer difficulty involved in manually constructing a complete reference standard...... from scratch, we propose to construct the reference using results from all algorithms that are to be evaluated. We start by subdividing each segmented airway tree into its individual branch segments. Each branch segment is then visually scored by trained observers to determine whether...... or not it is a correctly segmented part of the airway tree. Finally, the reference airway trees are constructed by taking the union of all correctly extracted branch segments. Fifteen airway tree extraction algorithms from different research groups are evaluated on a diverse set of 20 chest computed tomography (CT) scans...

  8. Airway injury during high-level exercise.

    Science.gov (United States)

    Kippelen, Pascale; Anderson, Sandra D

    2012-05-01

    Airway epithelial cells act as a physical barrier against environmental toxins and injury, and modulate inflammation and the immune response. As such, maintenance of their integrity is critical. Evidence is accumulating to suggest that exercise can cause injury to the airway epithelium. This seems the case particularly for competitive athletes performing high-level exercise, or when exercise takes place in extreme environmental conditions such as in cold dry air or in polluted air. Dehydration of the small airways and increased forces exerted on to the airway surface during severe hyperpnoea are thought to be key factors in determining the occurrence of injury of the airway epithelium. The injury-repair process of the airway epithelium may contribute to the development of the bronchial hyper-responsiveness that is documented in many elite athletes.

  9. Cranial nerve palsies

    International Nuclear Information System (INIS)

    Ruggieri, P.; Adelizzi, J.; Modic, M.T.; Ross, J.S.; Tkach, J.; Masaryk, T.J.

    1990-01-01

    This paper evaluates the utility of multiplanar reconstructions (MPRs) of three-dimensional (3D) MR angiography data sets in the examination of patients with cranial nerve palsies. The authors hypothesis was that 3D data could be reformatted to highlight the intricate spatial relationships of vessels to adjacent neural tissues by taking advantage of the high vessel-parenchyma contrast in high-resolution 3D time-of-flight sequences. Twenty patients with cranial nerve palsies and 10 asymptomatic patients were examined with coronal T1-weighted and axial T2-weighted imaging plus a gadolinium-enhanced 3D MRA sequence (40/7/15 degrees, axial 60-mm volume, 0.9-mm isotropic resolution). Cranial nerves II-VIII were subsequently evaluated on axial and reformatted coronal and/or sagittal images

  10. Supramammillary afferents to guinea pig hippocampus contain substance P-like immunoreactivity.

    Science.gov (United States)

    Gall, C; Selawski, L

    1984-10-12

    The origin of substance P immunoreactive (SPI) axons in guinea pig hippocampus was analyzed using immunocytochemical techniques combined with transections and retrograde transport of fluorescent dye. A unilateral depletion of hippocampal axonal SPI was observed following ipsilateral transection of rostral hippocampus and fibria suggesting that the vast majority of SPI axons in hippocampus are extrinsic afferents which enter the structure from the septal pole. The combined use of immunocytochemistry and fluorescent dye transport demonstrated the supramammillary region of the hypothalamus to be the only area where dye-labeled hippocampal afferent neurons also exhibited SPI. These data indicate that the supramammillary region is the principal source of SPI axons in guinea pig hippocampus and, most probably, in the hippocampus of other animals (squirrel, cat, monkey) sharing a similar pattern of axonal SPI.

  11. Vasodilatation of afferent arterioles and paradoxical increase of renal vascular resistance by furosemide in mice

    DEFF Research Database (Denmark)

    Oppermann, Mona; Hansen, Pernille B; Castrop, Hayo

    2007-01-01

    Loop diuretics like furosemide have been shown to cause renal vasodilatation in dogs and humans, an effect thought to result from both a direct vascular dilator effect and from inhibition of tubuloglomerular feedback. In isolated perfused afferent arterioles preconstricted with angiotensin II or N......(G)-nitro-L-arginine methyl ester, furosemide caused a dose-dependent increase of vascular diameter, but it was without effect in vessels from NKCC1-/- mice suggesting that inhibition of NKCC1 mediates dilatation in afferent arterioles. In the intact kidney, however, furosemide (2 mg/kg iv) caused a 50.5 +/- 3% reduction...... of total renal blood flow (RBF) and a 27% reduction of superficial blood flow (SBF) accompanied by a marked and immediate increase of tubular pressure and volume. At 10 mg/kg, furosemide reduced RBF by 60.4 +/- 2%. Similarly, NKCC1-/- mice responded to furosemide with a 45.4% decrease of RBF and a 29...

  12. Choroidal rupture and optic nerve injury with equipment designated as 'child-safe'.

    Science.gov (United States)

    Petrarca, Robert; Saldana, Manuel

    2012-08-27

    Blunt ocular trauma from a child's plastic foam-covered toy baseball bat caused traumatic optic neuropathy and choroidal rupture in a 9-year-old child. The examination revealed a visual acuity of 6/60, a relative afferent pupillary defect, optic nerve swelling, commotio retinae and retinal haemorrhages. There was no orbital fracture or intraorbital haematoma on CT scanning. Optical coherence tomography showed macular oedema and disruption of the retinal pigment epithelium and Bruch's membrane. The child was admitted for intravenous methylprednisolone and discharged on topical steroid treatment. At 1 month follow-up, visual acuity had improved to 6/12. Optic nerve swelling had resolved and the fundus had two crescent-shaped choroidal rupture scars. Choroidal rupture and optic neuropathy can be secondary to indirect trauma, and even when the mechanism of injury is with a piece of equipment designated as suitable for children, serious ocular injury can occur.

  13. Central-peripheral neural network interactions evoked by vagus nerve stimulation: functional consequences on control of cardiac function.

    Science.gov (United States)

    Ardell, Jeffrey L; Rajendran, Pradeep S; Nier, Heath A; KenKnight, Bruce H; Armour, J Andrew

    2015-11-15

    Using vagus nerve stimulation (VNS), we sought to determine the contribution of vagal afferents to efferent control of cardiac function. In anesthetized dogs, the right and left cervical vagosympathetic trunks were stimulated in the intact state, following ipsilateral or contralateral vagus nerve transection (VNTx), and then following bilateral VNTx. Stimulations were performed at currents from 0.25 to 4.0 mA, frequencies from 2 to 30 Hz, and a 500-μs pulse width. Right or left VNS evoked significantly greater current- and frequency-dependent suppression of chronotropic, inotropic, and lusitropic function subsequent to sequential VNTx. Bradycardia threshold was defined as the current first required for a 5% decrease in heart rate. The threshold for the right vs. left vagus-induced bradycardia in the intact state (2.91 ± 0.18 and 3.47 ± 0.20 mA, respectively) decreased significantly with right VNTx (1.69 ± 0.17 mA for right and 3.04 ± 0.27 mA for left) and decreased further following bilateral VNTx (1.29 ± 0.16 mA for right and 1.74 ± 0.19 mA for left). Similar effects were observed following left VNTx. The thresholds for afferent-mediated effects on cardiac parameters were 0.62 ± 0.04 and 0.65 ± 0.06 mA with right and left VNS, respectively, and were reflected primarily as augmentation. Afferent-mediated tachycardias were maintained following β-blockade but were eliminated by VNTx. The increased effectiveness and decrease in bradycardia threshold with sequential VNTx suggest that 1) vagal afferents inhibit centrally mediated parasympathetic efferent outflow and 2) the ipsilateral and contralateral vagi exert a substantial buffering capacity. The intact threshold reflects the interaction between multiple levels of the cardiac neural hierarchy. Copyright © 2015 the American Physiological Society.

  14. Nerve Transfers in Tetraplegia.

    Science.gov (United States)

    Fox, Ida K

    2016-05-01

    Hand and upper extremity function is instrumental to basic activities of daily living and level of independence in cervical spinal cord injury (SCI). Nerve transfer surgery is a novel and alternate approach for restoring function in SCI. This article discusses the biologic basis of nerve transfers in SCI, patient evaluation, management, and surgical approaches. Although the application of this technique is not new; recent case reports and case series in the literature have increased interest in this field. The challenges are to improve function, achieve maximal gains in function, avoid complications, and to primum non nocere. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Primary afferent terminal sprouting after a cervical dorsal rootlet section in the macaque monkey.

    Science.gov (United States)

    Darian-Smith, Corinna

    2004-03-01

    We examined the role of primary afferent neurons in the somatosensory cortical "reactivation" that occurs after a localized cervical dorsal root lesion (Darian-Smith and Brown [2000] Nat. Neurosci. 3:476-481). After section of the dorsal rootlets that enervate the macaque's thumb and index finger (segments C6-C8), the cortical representation of these digits was initially silenced but then re-emerged for these same digits over 2-4 postlesion months. Cortical reactivation was accompanied by the emergence of physiologically detectable input from these same digits within dorsal rootlets bordering the lesion site. We investigated whether central axonal sprouting of primary afferents spared by the rhizotomy could mediate this cortical reactivation. The cortical representation of the hand was mapped electrophysiologically 15-25 weeks after the dorsal rootlet section to define this reactivation. Cholera toxin subunit B conjugated to horseradish peroxidase was then injected into the thumb and index finger pads bilaterally to label the central terminals of any neurons that innervated these digits. Primary afferent terminal proliferation was assessed in the spinal dorsal horn and cuneate nucleus at 7 days and 15-25 postlesion weeks. Labeled terminal bouton distributions were reconstructed and the "lesion" and control sides compared within each monkey. Distributions were significantly larger on the side of the lesion in the dorsal horn and cuneate nucleus at 15-25 weeks after the dorsal rootlet section, than those mapped only 7 days postlesion. Our results provide direct evidence for localized sprouting of spared (uninjured) primary afferent terminals in the dorsal horn and cuneate nucleus after a restricted dorsal root injury. Copyright 2004 Wiley-Liss, Inc.

  16. Population coding of forelimb joint kinematics by peripheral afferents in monkeys.

    Directory of Open Access Journals (Sweden)

    Tatsuya Umeda

    Full Text Available Various peripheral receptors provide information concerning position and movement to the central nervous system to achieve complex and dexterous movements of forelimbs in primates. The response properties of single afferent receptors to movements at a single joint have been examined in detail, but the population coding of peripheral afferents remains poorly defined. In this study, we obtained multichannel recordings from dorsal root ganglion (DRG neurons in cervical segments of monkeys. We applied the sparse linear regression (SLiR algorithm to the recordings, which selects useful input signals to reconstruct movement kinematics. Multichannel recordings of peripheral afferents were performed by inserting multi-electrode arrays into the DRGs of lower cervical segments in two anesthetized monkeys. A total of 112 and 92 units were responsive to the passive joint movements or the skin stimulation with a painting brush in Monkey 1 and Monkey 2, respectively. Using the SLiR algorithm, we reconstructed the temporal changes of joint angle, angular velocity, and acceleration at the elbow, wrist, and finger joints from temporal firing patterns of the DRG neurons. By automatically selecting a subset of recorded units, the SLiR achieved superior generalization performance compared with a regularized linear regression algorithm. The SLiR selected not only putative muscle units that were responsive to only the passive movements, but also a number of putative cutaneous units responsive to the skin stimulation. These results suggested that an ensemble of peripheral primary afferents that contains both putative muscle and cutaneous units encode forelimb joint kinematics of non-human primates.

  17. Group Ia afferents likely contribute to short-latency interlimb reflexes in the human biceps femoris muscle

    DEFF Research Database (Denmark)

    Stevenson, Andrew James Thomas; Kamavuako, Ernest Nlandu; Geertsen, Svend Sparre

    2017-01-01

    amplitudes (4 vs. 8°) at the same 150°/s velocity (p’s > 0.08). Conclusion: Because fast conducting group Ia muscle spindle afferents are sensitive to changes in muscle stretch velocity, while group II spindle afferents are sensitive to changes in amplitude (Grey et al., JPhysiol., 2001; Matthews, Trends...... Neurosci., 1991), group Ia velocity sensitive muscle spindle afferents likely contribute to the short-latency crossed spinal reflexes in the cBF muscle following iKnee joint rotations. This supports the findings for the short-latency crossed responses in the human soleus muscle (Stubbs & Mrachacz...... neurons in humans, with primary contributions from group Ia muscle spindle afferents....

  18. Specialized Nerve Tests: EMG, NCV and SSEP

    Science.gov (United States)

    ... grouped according to where they leave the spinal column. There are eight pairs of neck (cervical) nerves, 12 pairs of upper back (thoracic) nerves, five pairs of lower back (lumbar) nerves, five pairs of pelvis (sacral) nerves and ...

  19. Improvised bubble continuous positive airway pressure (BCPAP ...

    African Journals Online (AJOL)

    Improvised bubble continuous positive airway pressure (BCPAP) device at the National Hospital Abuja gives immediate improvement in respiratory rate and oxygenation in neonates with respiratory distress.

  20. Cholinergic Regulation of Airway Inflammation and Remodelling

    Directory of Open Access Journals (Sweden)

    Saeed Kolahian

    2012-01-01

    Full Text Available Acetylcholine is the predominant parasympathetic neurotransmitter in the airways that regulates bronchoconstriction and mucus secretion. Recent findings suggest that acetylcholine regulates additional functions in the airways, including inflammation and remodelling during inflammatory airway diseases. Moreover, it has become apparent that acetylcholine is synthesized by nonneuronal cells and tissues, including inflammatory cells and structural cells. In this paper, we will discuss the regulatory role of acetylcholine in inflammation and remodelling in which we will focus on the role of the airway smooth muscle cell as a target cell for acetylcholine that modulates inflammation and remodelling during respiratory diseases such as asthma and COPD.

  1. Laparoscopic Revision of an Omega Loop Gastric Bypass to Treat Afferent Loop Syndrome.

    Science.gov (United States)

    Kassir, Radwan; Blanc, Pierre; Lointier, Patrice; Breton, Christophe; Debs, Tarek; Tiffet, Olivier

    2015-10-01

    The omega loop gastric bypass (OLGB) has become a very commonly performed bariatric procedure because of the advantages it carries over the Roux en Y gastric bypass (RYGBP). However, mini gastric bypass is a misnomer, as this procedure is more malabsorptive than the RYGBP. Recently, it is called single or one anastomosis gastric bypass. The omega loop procedure is associated with a risk of afferent loop syndrome, a known complication of the Billroth II (Finsterer) operation. This rare complication of the OLGB can be debilitating, serious, and deadly. Afferent loop syndrome should be suspected in case of malabsorption syndrome with chronic diarrhea, steatorrhea, iron-deficiency anemia, edema, emaciation, and osteomalacia and also in case of simple biological anomalies such as macrocytosis or megaloblastic anemia. The diagnosis can be confirmed by measuring bacterial overgrowth, although this requires a jejunal aspirate performed during endoscopy with jejunal intubation. A microbial population of more than 106 organisms per milliliter of aspirate is pathological. Afferent loop syndrome is encountered less frequently now that the number of gastrectomies has dropped. Yet, with the omega loop bypass procedure becoming more common, surgeons must again be made aware of this potential complication.

  2. pH-evoked dural afferent signaling is mediated by ASIC3 and is sensitized by mast cell mediators.

    Science.gov (United States)

    Yan, Jin; Wei, Xiaomei; Bischoff, Christina; Edelmayer, Rebecca M; Dussor, Gregory

    2013-09-01

    Prior studies have shown that decreased meningeal pH activates dural afferents via opening of acid-sensing ion channels (ASICs), suggesting one pathophysiological mechanism for the generation of headaches. The studies described here further examined the ASIC subtype mediating pH-induced dural-afferent activation and examined whether sensitization influences pH responses. Given the potential importance of meningeal mast cells to headache, the goal of this study was to evaluate dural afferent responses to pH following sensitization with mast cell mediators. Cutaneous allodynia was measured in rats following stimulation of the dura with decreased pH alone or in combination with mast cell mediators. Trigeminal ganglion neurons retrogradely labeled from the dura were stained with an ASIC3 antibody using immunohistochemistry. Current and action potentials evoked by changes in pH alone or in combination with mast cell mediators were measured in retrogradely labeled dural afferents using patch-clamp electrophysiology. pH-sensitive dural afferents generated currents in response to the ASIC3 activator 2-guanidine-4-methylquinazoline (GMQ), approximately 80% of these neurons express ASIC3 protein, and pH-evoked behavioral responses were inhibited by the ASIC3 blocker APETx2. Following exposure to mast cell mediators, dural afferents exhibited increased pH-evoked excitability, and cutaneous allodynia was observed at higher pH than with pH stimuli alone. These data indicate that the predominant ASIC subtype responding to decreased meningeal pH is ASIC3. Additionally, they demonstrate that in the presence of inflammation, dural afferents respond to even smaller decreases in pH providing further support for the ability of small pH changes within the meninges to initiate afferent input leading to headache. © 2013 American Headache Society.

  3. Modulation of visceral hypersensitivity by glial cell line-derived neurotrophic factor family receptor α-3 in colorectal afferents

    OpenAIRE

    Tanaka, T.; Shinoda, M.; Feng, B.; Albers, K. M.; Gebhart, G. F.

    2010-01-01

    Irritable bowel syndrome is characterized by colorectal hypersensitivity and contributed to by sensitized mechanosensitive primary afferents and recruitment of mechanoinsensitive (silent) afferents. Neurotrophic factors are well known to orchestrate dynamic changes in the properties of sensory neurons. Although pain modulation by proteins in the glial cell line-derived neurotrophic factor (GDNF) family has been documented in various pathophysiological states, their role in colorectal hypersen...

  4. Nerve Transfer versus Interpositional Nerve Graft Reconstruction for Posttraumatic, Isolated Axillary Nerve Injuries: A Systematic Review.

    Science.gov (United States)

    Koshy, John C; Agrawal, Nikhil A; Seruya, Mitchel

    2017-11-01

    The purpose of this study was to compare functional outcomes between nerve grafting and nerve transfer procedures in the setting of isolated, posttraumatic axillary nerve injuries. A systematic review was performed using the PubMed, Scopus, and Cochrane databases to identify all cases of isolated, posttraumatic axillary nerve injuries in patients aged 18 years or older. Patients who underwent axillary nerve reconstruction were included and categorized by technique: graft or transfer. Demographics were recorded, including age, time to operation, and presence of concomitant injuries. Functional outcomes were evaluated, including British Medical Research Council strength and range of motion for shoulder abduction. Ten retrospective studies met criteria, for a total of 66 patients (20 nerve grafts and 46 nerve transfers). Median time from injury to operation was equivalent across the nerve graft and nerve transfer groups (8.0 months versus 7.0 months; p = 0.41). Postoperative follow-up was 24.0 months for nerve grafting versus 18.5 months for nerve transfer (p = 0.13). Clinically useful shoulder abduction, defined as British Medical Research Council grade M3 or greater, was obtained in 100 percent of nerve graft patients versus 87 percent of nerve transfer patients (p = 0.09). Grade M4 or better strength was obtained in 85 percent of nerve graft patients and 73.9 percent of nerve transfer patients (p = 0.32). Significant differences in functional outcomes between nerve graft and transfer procedures for posttraumatic axillary nerve injuries are not apparent at this time. Prospective outcomes studies are needed to better elucidate whether functional differences do exist. Therapeutic, IV.

  5. Airway contractility and remodeling : Links to asthma symptoms

    NARCIS (Netherlands)

    West, Adrian R.; Syyong, Harley T.; Siddiqui, Sana; Pascoe, Chris D.; Murphy, Thomas M.; Maarsingh, Harm; Deng, Linhong; Maksym, Geoffrey N.; Bosse, Ynuk

    Respiratory symptoms are largely caused by obstruction of the airways. In asthma, airway narrowing mediated by airway smooth muscle (ASM) contraction contributes significantly to obstruction. The spasmogens produced following exposure to environmental triggers, such as viruses or allergens, are

  6. Semi-automated tabulation of the 3D topology and morphology of branching networks using CT: application to the airway tree

    International Nuclear Information System (INIS)

    Sauret, V.; Bailey, A.G.

    1999-01-01

    Detailed information on biological branching networks (optical nerves, airways or blood vessels) is often required to improve the analysis of 3D medical imaging data. A semi-automated algorithm has been developed to obtain the full 3D topology and dimensions (direction cosine, length, diameter, branching and gravity angles) of branching networks using their CT images. It has been tested using CT images of a simple Perspex branching network and applied to the CT images of a human cast of the airway tree. The morphology and topology of the computer derived network were compared with the manually measured dimensions. Good agreement was found. The airways dimensions also compared well with previous values quoted in literature. This algorithm can provide complete data set analysis much more quickly than manual measurements. Its use is limited by the CT resolution which means that very small branches are not visible. New data are presented on the branching angles of the airway tree. (author)

  7. Electrophysiological characterization of texture information slip-resistance dependent in the rat vibrissal nerve

    Directory of Open Access Journals (Sweden)

    Albarracín Ana L

    2011-04-01

    Full Text Available Abstract Background Studies in tactile discrimination agree that rats are able to learn a rough-smooth discrimination task by actively touching (whisking objects with their vibrissae. In particular, we focus on recent evidence of how neurons at different levels of the sensory pathway carry information about tactile stimuli. Here, we analyzed the multifiber afferent discharge of one vibrissal nerve during active whisking. Vibrissae movements were induced by electrical stimulation of motor branches of the facial nerve. We used sandpapers of different grain size as roughness discrimination surfaces and we also consider the change of vibrissal slip-resistance as a way to improve tactile information acquisition. The amplitude of afferent activity was analyzed according to its Root Mean Square value (RMS. The comparisons among experimental situation were quantified by using the information theory. Results We found that the change of the vibrissal slip-resistance is a way to improve the roughness discrimination of surfaces. As roughness increased, the RMS values also increased in almost all cases. In addition, we observed a better discrimination performance in the retraction phase (maximum amount of information. Conclusions The evidence of amplitude changes due to roughness surfaces and slip-resistance levels allows to speculate that texture information is slip-resistance dependent at peripheral level.

  8. The Vagus Nerve at the Interface of the Microbiota-Gut-Brain Axis.

    Science.gov (United States)

    Bonaz, Bruno; Bazin, Thomas; Pellissier, Sonia

    2018-01-01

    The microbiota, the gut, and the brain communicate through the microbiota-gut-brain axis in a bidirectional way that involves the autonomic nervous system. The vagus nerve (VN), the principal component of the parasympathetic nervous system, is a mixed nerve composed of 80% afferent and 20% efferent fibers. The VN, because of its role in interoceptive awareness, is able to sense the microbiota metabolites through its afferents, to transfer this gut information to the central nervous system where it is integrated in the central autonomic network, and then to generate an adapted or inappropriate response. A cholinergic anti-inflammatory pathway has been described through VN's fibers, which is able to dampen peripheral inflammation and to decrease intestinal permeability, thus very probably modulating microbiota composition. Stress inhibits the VN and has deleterious effects on the gastrointestinal tract and on the microbiota, and is involved in the pathophysiology of gastrointestinal disorders such as irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) which are both characterized by a dysbiosis. A low vagal tone has been described in IBD and IBS patients thus favoring peripheral inflammation. Targeting the VN, for example through VN stimulation which has anti-inflammatory properties, would be of interest to restore homeostasis in the microbiota-gut-brain axis.

  9. Attenuation of early phase inflammation by cannabidiol prevents pain and nerve damage in rat osteoarthritis

    Science.gov (United States)

    Philpott, Holly T.; O'Brien, Melissa; McDougall, Jason J.

    2017-01-01

    Abstract Osteoarthritis (OA) is a multifactorial joint disease, which includes joint degeneration, intermittent inflammation, and peripheral neuropathy. Cannabidiol (CBD) is a noneuphoria producing constituent of cannabis that has the potential to relieve pain. The aim of this study was to determine whether CBD is anti-nociceptive in OA, and whether inhibition of inflammation by CBD could prevent the development of OA pain and joint neuropathy. Osteoarthritis was induced in male Wistar rats (150-175 g) by intra-articular injection of sodium monoiodoacetate (MIA; 3 mg). On day 14 (end-stage OA), joint afferent mechanosensitivity was assessed using in vivo electrophysiology, whereas pain behaviour was measured by von Frey hair algesiometry and dynamic incapacitance. To investigate acute joint inflammation, blood flow and leukocyte trafficking were measured on day 1 after MIA. Joint nerve myelination was calculated by G-ratio analysis. The therapeutic and prophylactic effects of peripheral CBD (100-300 μg) were assessed. In end-stage OA, CBD dose-dependently decreased joint afferent firing rate, and increased withdrawal threshold and weight bearing (P inflammation was reduced by local CBD treatment (P pain at later time points (P pain. Prophylactic CBD treatment prevented the later development of pain and nerve damage in these OA joints. These findings suggest that CBD may be a safe, useful therapeutic for treating OA joint neuropathic pain. PMID:28885454

  10. Overview of Optic Nerve Disorders

    Science.gov (United States)

    ... Liver and Gallbladder Disorders Lung and Airway Disorders Men's Health Issues Mental Health Disorders Mouth and Dental Disorders Older People’s ... Liver and Gallbladder Disorders Lung and Airway Disorders Men's Health Issues Mental Health Disorders Mouth and Dental Disorders Older People’s ...

  11. Tumors of the optic nerve

    DEFF Research Database (Denmark)

    Lindegaard, Jens; Heegaard, Steffen

    2009-01-01

    in the nerve (e.g., astrocytes and meningothelial cells). The optic nerve may also be invaded from tumors originating elsewhere (secondary tumors), invading the nerve from adjacent structures (e.g., choroidal melanoma and retinoblastoma) or from distant sites (e.g., lymphocytic infiltration and distant...

  12. Anatomy of the trigeminal nerve

    NARCIS (Netherlands)

    van Eijden, T.M.G.J.; Langenbach, G.E.J.; Baart, J.A.; Brand, H.S.

    2017-01-01

    The trigeminal nerve is the fifth cranial nerve (n. V), which plays an important role in the innervation of the head and neck area, together with other cranial and spinal nerves. Knowledge of the nerve’s anatomy is very important for the correct application of local anaesthetics.

  13. Imaging the ocular motor nerves.

    NARCIS (Netherlands)

    Ferreira, T.; Verbist, B.M.; Buchem, M. van; Osch, T. van; Webb, A.

    2010-01-01

    The ocular motor nerves (OMNs) comprise the oculomotor, trochlear and the abducens nerves. According to their course, they are divided into four or five anatomic segments: intra-axial, cisternal, cavernous and intra-orbital and, for the abducens nerve, an additional interdural segment. Magnetic

  14. H-reflex up-conditioning encourages recovery of EMG activity and H-reflexes after sciatic nerve transection and repair in rats.

    Science.gov (United States)

    Chen, Yi; Wang, Yu; Chen, Lu; Sun, Chenyou; English, Arthur W; Wolpaw, Jonathan R; Chen, Xiang Yang

    2010-12-01

    Operant conditioning of the spinal stretch reflex or its electrical analog, the H-reflex, produces spinal cord plasticity and can thereby affect motoneuron responses to primary afferent input. To explore whether this conditioning can affect the functional outcome after peripheral nerve injury, we assessed the effect of up-conditioning soleus (SOL) H-reflex on SOL and tibialis anterior (TA) function after sciatic nerve transection and repair. Sprague Dawley rats were implanted with EMG electrodes in SOL and TA and stimulating cuffs on the posterior tibial nerve. After control data collection, the sciatic nerve was transected and repaired and the rat was exposed for 120 d to continued control data collection (TC rats) or SOL H-reflex up-conditioning (TU rats). At the end of data collection, motoneurons that had reinnervated SOL and TA were labeled retrogradely. Putative primary afferent terminals [i.e., terminals containing vesicular glutamate transporter-1 (VGLUT1)] on SOL motoneurons were studied immunohistochemically. SOL (and probably TA) background EMG activity recovered faster in TU rats than in TC rats, and the final recovered SOL H-reflex was significantly larger in TU than in TC rats. TU and TC rats had significantly fewer labeled motoneurons and higher proportions of double-labeled motoneurons than untransected rats. VGLUT1 terminals were significantly more numerous on SOL motoneurons of TU than TC rats. Combined with the larger H-reflexes in TU rats, this anatomical finding supports the hypothesis that SOL H-reflex up-conditioning strengthened primary afferent reinnervation of SOL motoneurons. These results suggest that H-reflex up-conditioning may improve functional recovery after nerve injury and repair.

  15. Nerve growth factor promotes human hemopoietic colony growth and differentiation

    International Nuclear Information System (INIS)

    Matsuda, H.; Coughlin, M.D.; Bienenstock, J.; Denburg, J.A.

    1988-01-01

    Nerve growth factor (NGF) is a neurotropic polypeptide necessary for the survival and growth of some central neurons, as well as sensory afferent and sympathetic neurons. Much is now known of the structural and functional characteristics of NGF, whose gene has recently been clones. Since it is synthesized in largest amounts by the male mouse submandibular gland, its role exclusively in nerve growth is questionable. These experiments indicate that NGF causes a significant stimulation of granulocyte colonies grown from human peripheral blood in standard hemopoietic methylcellulose assays. Further, NGF appears to act in a relatively selective fashion to induce the differentiation of eosinophils and basophils/mast cells. Depletion experiments show that the NGF effect may be T-cell dependent and that NGF augments the colony-stimulating effect of supernatants from the leukemic T-cell (Mo) line. The hemopoietic activity of NGF is blocked by 125 I-polyclonal and monoclonal antibodies to NGF. The authors conclude that NGF may indirectly act as a local growth factor in tissues other than those of the nervous system by causing T cells to synthesize or secrete molecules with colony-stimulating activity. In view of the synthesis of NGF in tissue injury, the involvement of basophils/mast cells and eosinophils in allergic and other inflammatory processes, and the association of mast cells with fibrosis and tissue repair, they postulate that NGF plays an important biological role in a variety of repair processes

  16. Nerve conduction and excitability studies in peripheral nerve disorders

    DEFF Research Database (Denmark)

    Krarup, Christian; Moldovan, Mihai

    2009-01-01

    PURPOSE OF REVIEW: The review is aimed at providing information about the role of nerve excitability studies in peripheral nerve disorders. It has been known for many years that the insight into peripheral nerve pathophysiology provided by conventional nerve conduction studies is limited. Nerve....... Studies of different metabolic neuropathies have assessed the influence of uremia, diabetes and ischemia, and the use of these methods in toxic neuropathies has allowed pinpointing damaging factors. Various mutations in ion channels associated with central nervous system disorders have been shown to have...

  17. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    Kiilgaard, Jens Folke; Pedersen, D B; Eysteinsson, T

    2004-01-01

    The authors have previously reported that carbonic anhydrase inhibitors such as acetazolamide and dorzolamide raise optic nerve oxygen tension (ONPO(2)) in pigs. The purpose of the present study was to investigate whether timolol, which belongs to another group of glaucoma drugs called beta...

  18. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    Kiilgaard, Jens Folke; Pedersen, D B; Eysteinsson, T

    2004-01-01

    The authors have previously reported that carbonic anhydrase inhibitors such as acetazolamide and dorzolamide raise optic nerve oxygen tension (ONPO(2)) in pigs. The purpose of the present study was to investigate whether timolol, which belongs to another group of glaucoma drugs called beta block...

  19. Optic nerve sheath meningiomas

    NARCIS (Netherlands)

    Saeed, Peerooz; Rootman, Jack; Nugent, Robert A.; White, Valerie A.; Mackenzie, Ian R.; Koornneef, Leo

    2003-01-01

    To study the natural history and growth of optic nerve sheath meningiomas and evaluate their management outcome. Clinicopathologic retrospective noncomparative case series. A retrospective study of 88 patients who were treated between 1976 and 1999 at the University of British Columbia and the

  20. Neurally mediated airway constriction in human and other species: a comparative study using precision-cut lung slices (PCLS.

    Directory of Open Access Journals (Sweden)

    Marco Schlepütz

    Full Text Available The peripheral airway innervation of the lower respiratory tract of mammals is not completely functionally characterized. Recently, we have shown in rats that precision-cut lung slices (PCLS respond to electric field stimulation (EFS and provide a useful model to study neural airway responses in distal airways. Since airway responses are known to exhibit considerable species differences, here we examined the neural responses of PCLS prepared from mice, rats, guinea pigs, sheep, marmosets and humans. Peripheral neurons were activated either by EFS or by capsaicin. Bronchoconstriction in response to identical EFS conditions varied between species in magnitude. Frequency response curves did reveal further species-dependent differences of nerve activation in PCLS. Atropine antagonized the EFS-induced bronchoconstriction in human, guinea pig, sheep, rat and marmoset PCLS, showing cholinergic responses. Capsaicin (10 µM caused bronchoconstriction in human (4 from 7 and guinea pig lungs only, indicating excitatory non-adrenergic non-cholinergic responses (eNANC. However, this effect was notably smaller in human responder (30 ± 7.1% than in guinea pig (79 ± 5.1% PCLS. The transient receptor potential (TRP channel blockers SKF96365 and ruthenium red antagonized airway contractions after exposure to EFS or capsaicin in guinea pigs. In conclusion, the different species show distinct patterns of nerve-mediated bronchoconstriction. In the most common experimental animals, i.e. in mice and rats, these responses differ considerably from those in humans. On the other hand, guinea pig and marmoset monkey mimic human responses well and may thus serve as clinically relevant models to study neural airway responses.

  1. Repetitive Diving in Trained Rats Still Increases Fos Production in Brainstem Neurons after Bilateral Sectioning of the Anterior Ethmoidal Nerve.

    Science.gov (United States)

    McCulloch, Paul F; Warren, Erik A; DiNovo, Karyn M

    2016-01-01

    This research was designed to investigate the role of the anterior ethmoidal nerve (AEN) during repetitive trained diving in rats, with specific attention to activation of afferent and efferent brainstem nuclei that are part of this reflexive response. The AEN innervates the nose and nasal passages and is thought to be an important component of the afferent limb of the diving response. Male Sprague-Dawley rats (N = 24) were trained to swim and dive through a 5 m underwater maze. Some rats (N = 12) had bilateral sectioning of the AEN, others a Sham surgery (N = 12). Twelve rats (6 AEN cut and 6 Sham) had 24 post-surgical dive trials over 2 h to activate brainstem neurons to produce Fos, a neuronal activation marker. Remaining rats were non-diving controls. Diving animals had significantly more Fos-positive neurons than non-diving animals in the caudal pressor area, ventral medullary dorsal horn, ventral paratrigeminal nucleus, nucleus tractus solitarius, rostral ventrolateral medulla, Raphe nuclei, A5, Locus Coeruleus, and Kölliker-Fuse area. There were no significant differences in brainstem Fos labeling in rats diving with and without intact AENs. Thus, the AENs are not required for initiation of the diving response. Other nerve(s) that innervate the nose and nasal passages, and/or suprabulbar activation of brainstem neurons, may be responsible for the pattern of neuronal activation observed during repetitive trained diving in rats. These results help define the central neuronal circuitry of the mammalian diving response.

  2. Repetitive Diving in Trained Rats Still Increases Fos Production in Brainstem Neurons after Bilateral Sectioning of the Anterior Ethmoidal Nerve

    Science.gov (United States)

    McCulloch, Paul F.; Warren, Erik A.; DiNovo, Karyn M.

    2016-01-01

    This research was designed to investigate the role of the anterior ethmoidal nerve (AEN) during repetitive trained diving in rats, with specific attention to activation of afferent and efferent brainstem nuclei that are part of this reflexive response. The AEN innervates the nose and nasal passages and is thought to be an important component of the afferent limb of the diving response. Male Sprague-Dawley rats (N = 24) were trained to swim and dive through a 5 m underwater maze. Some rats (N = 12) had bilateral sectioning of the AEN, others a Sham surgery (N = 12). Twelve rats (6 AEN cut and 6 Sham) had 24 post-surgical dive trials over 2 h to activate brainstem neurons to produce Fos, a neuronal activation marker. Remaining rats were non-diving controls. Diving animals had significantly more Fos-positive neurons than non-diving animals in the caudal pressor area, ventral medullary dorsal horn, ventral paratrigeminal nucleus, nucleus tractus solitarius, rostral ventrolateral medulla, Raphe nuclei, A5, Locus Coeruleus, and Kölliker-Fuse area. There were no significant differences in brainstem Fos labeling in rats diving with and without intact AENs. Thus, the AENs are not required for initiation of the diving response. Other nerve(s) that innervate the nose and nasal passages, and/or suprabulbar activation of brainstem neurons, may be responsible for the pattern of neuronal activation observed during repetitive trained diving in rats. These results help define the central neuronal circuitry of the mammalian diving response. PMID:27148082

  3. Teaching consultants airway management skills.

    Science.gov (United States)

    Nargozian, Charles

    2004-01-01

    Airway management skills are integral to the practice of anaesthesiology and also to the practice of emergency medicine and allied health professions such as respiratory care, emergency medical technology, and emergency and critical care nursing. The basic information to be taught is the same but the level of detail will vary depending on the audience. The learning process usually involves progression from didactic lessons to skills training on inanimate models to supervised clinical practice. Modalities that may be used for skills training include cadavers, recently dead patients, videotapes, mannequins, simulators and virtual reality trainers. To maintain knowledge and skills, review and possible retraining should be conducted on an approximately annual basis.

  4. Airway management: induced tension pneumoperitoneum.

    Science.gov (United States)

    Ahmed, Khedher; Amine, El Ghali Mohamed; Abdelbaki, Azouzi; Jihene, Ayachi; Khaoula, Meddeb; Yamina, Hamdaoui; Mohamed, Boussarsar

    2016-01-01

    Pneumoperitoneum is not always associated with hollow viscus perforation. Such condition is called non-surgical or spontaneous pneumoperitoneum. Intrathoracic causes remain the most frequently reported mechanism inducing this potentially life threatening complication. This clinical condition is associated with therapeutic dilemma. We report a case of a massive isolated pneumoperitoneum causing acute abdominal hypertension syndrome, in a 75 year female, which occurred after difficult airway management and mechanical ventilation. Emergent laparotomy yielded to full recovery. The recognition of such cases for whom surgical management can be avoided is primordial to avoid unnecessary laparotomy and its associated morbidity particularly in the critically ill.

  5. Native Small Airways Secrete Bicarbonate

    OpenAIRE

    Shamsuddin, A. K. M.; Quinton, Paul M.

    2014-01-01

    Since the discovery of Cl− impermeability in cystic fibrosis (CF) and the cloning of the responsible channel, CF pathology has been widely attributed to a defect in epithelial Cl− transport. However, loss of bicarbonate (HCO3−) transport also plays a major, possibly more critical role in CF pathogenesis. Even though HCO3− transport is severely affected in the native pancreas, liver, and intestines in CF, we know very little about HCO3− secretion in small airways, the principle site of morbidi...

  6. Airway management in spontaneously breathing anaesthetized children: comparison of the Laryngeal Mask Airway with the cuffed oropharyngeal airway.

    Science.gov (United States)

    Mamaya, Biruta

    2002-06-01

    The efficacy and safety of the smallest size of the cuffed oropharyngeal airway (COPA) for school age, spontaneously breathing children was investigated and compared with the Laryngeal Mask Airway (LMA). Seventy children of school age (7-16 years) were divided into two groups: the COPA (n=35) and the LMA (n=35). Induction was with propofol i.v. or halothane, nitrous oxide, oxygen and fentanyl. After depression of laryngopharyngeal reflexes, a COPA size 8 cm or an LMA was inserted. Ventilation was manually assisted until spontaneous breathing was established. For maintenance, propofol i.v. and fentanyl or halothane with nitrous oxide were used. Local anaesthesia or peripheral blocks were also used. Both extratracheal airways had a highly successful insertion rate, but more positional manoeuvres to achieve a satisfactory airway were required with the COPA, 28.6% versus LMA 2.9%. The need to change the method of airway management was higher (8.6%) in the COPA group. After induction, the need for assisted ventilation was higher in the LMA group 54.3% versus 20% in the COPA group. Airway reaction to cuff inflation was higher in the LMA group 14.3% versus COPA 5.7%. Problems during surgery were similar, except continuous chin support to establish an effective airway was more frequent (11.4%) in the COPA group. In the postoperative period, blood on the device and incidence of sore throat were detected less in the COPA group. The COPA is a good extratracheal airway that provides new possibilities for airway management in school age children with an adequate and well sealed airway, during spontaneous breathing or during short-term assisted manual ventilation.

  7. Pathology of the vestibulocochlear nerve

    Energy Technology Data Exchange (ETDEWEB)

    De Foer, Bert [Department of Radiology, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: bert.defoer@GZA.be; Kenis, Christoph [Department of Radiology, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: christophkenis@hotmail.com; Van Melkebeke, Deborah [Department of Neurology, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: Deborah.vanmelkebeke@Ugent.be; Vercruysse, Jean-Philippe [University Department of ENT, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: jphver@yahoo.com; Somers, Thomas [University Department of ENT, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: Thomas.somers@GZA.be; Pouillon, Marc [Department of Radiology, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: marc.pouillon@GZA.be; Offeciers, Erwin [University Department of ENT, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: Erwin.offeciers@GZA.be; Casselman, Jan W. [Department of Radiology, AZ Sint-Jan AV Hospital, Ruddershove 10, Bruges (Belgium); Consultant Radiologist, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium); Academic Consultent, University of Ghent (Belgium)], E-mail: jan.casselman@azbrugge.be

    2010-05-15

    There is a large scala of pathology affecting the vestibulocochlear nerve. Magnetic resonance imaging is the method of choice for the investigation of pathology of the vestibulocochlear nerve. Congenital pathology mainly consists of agenesis or hypoplasia of the vestibulocochlear nerve. Tumoral pathology affecting the vestibulocochlear nerve is most frequently located in the internal auditory canal or cerebellopontine angle. Schwannoma of the vestibulocochlear nerve is the most frequently found tumoral lesion followed by meningeoma, arachnoid cyst and epidermoid cyst. The most frequently encountered pathologies as well as some more rare entities are discussed in this chapter.

  8. Closed-loop afferent electrical stimulation for recovery of hand function in individuals with motor incomplete spinal injury: early clinical results.

    Science.gov (United States)

    Schildt, Christopher J; Thomas, Sarah H; Powell, Elizabeth S; Sawaki, Lumy; Sunderam, Sridhar

    2016-08-01

    Afferent electrical stimulation is known to augment the effect of rehabilitative therapy through use-dependent cortical plasticity. Experiments pairing transcranial magnetic stimulation (TMS) with peripheral nerve stimulation (PNS) have shown a timing-dependent effect on motor evoked potential (MEP) amplitude suggesting that PNS applied in closed-loop (CL) mode could augment this effect through positive reinforcement. We present early results from a clinical trial in which an EEG brain-machine interface (BMI) was used to apply PNS to two subjects in response to motor intent detected from sensorimotor cortex in a cue-driven hand grip task. Both subjects had stable incomplete cervical spinal cord injury (SCI) with impaired upper limb function commensurate with the injury level. Twelve sessions of CL-PNS applied over a 4-6 week period yielded results suggesting improved hand grip strength and increased task-related modulation of the EEG in one hand of both subjects, and increased TMS-measured motor map area in one. These observations suggest that rehabilitation using such interactive therapies could benefit affected individuals.

  9. Bronchology Treatment Of The Malignant Airway Stenosis

    International Nuclear Information System (INIS)

    Slivka, R. et al

    2007-01-01

    Central airway stenosis is benign or malignant etiology. Multidiscplinary approach is useful in treatment central airway stenosis. In inoperable cases, interventional bronchology is good therapeutic alternative. We can use NdYAG laser, argon plasma coagulation, elektrocautery, cryotherapy, photodynamic therapy and stents for obstruction release. In malignant stenosis, we combine often methods of the interventional bronchology with brachytherapy, chemotherapy and external radiotherapy. (author)

  10. Difficult airway response team: a novel quality improvement program for managing hospital-wide airway emergencies.

    Science.gov (United States)

    Mark, Lynette J; Herzer, Kurt R; Cover, Renee; Pandian, Vinciya; Bhatti, Nasir I; Berkow, Lauren C; Haut, Elliott R; Hillel, Alexander T; Miller, Christina R; Feller-Kopman, David J; Schiavi, Adam J; Xie, Yanjun J; Lim, Christine; Holzmueller, Christine; Ahmad, Mueen; Thomas, Pradeep; Flint, Paul W; Mirski, Marek A

    2015-07-01

    Difficult airway cases can quickly become emergencies, increasing the risk of life-threatening complications or death. Emergency airway management outside the operating room is particularly challenging. We developed a quality improvement program-the Difficult Airway Response Team (DART)-to improve emergency airway management outside the operating room. DART was implemented by a team of anesthesiologists, otolaryngologists, trauma surgeons, emergency medicine physicians, and risk managers in 2005 at The Johns Hopkins Hospital in Baltimore, Maryland. The DART program had 3 core components: operations, safety, and education. The operations component focused on developing a multidisciplinary difficult airway response team, standardizing the emergency response process, and deploying difficult airway equipment carts throughout the hospital. The safety component focused on real-time monitoring of DART activations and learning from past DART events to continuously improve system-level performance. This objective entailed monitoring the paging system, reporting difficult airway events and DART activations to a Web-based registry, and using in situ simulations to identify and mitigate defects in the emergency airway management process. The educational component included development of a multispecialty difficult airway curriculum encompassing case-based lectures, simulation, and team building/communication to ensure consistency of care. Educational materials were also developed for non-DART staff and patients to inform them about the needs of patients with difficult airways and ensure continuity of care with other providers after discharge. Between July 2008 and June 2013, DART managed 360 adult difficult airway events comprising 8% of all code activations. Predisposing patient factors included body mass index >40, history of head and neck tumor, prior difficult intubation, cervical spine injury, airway edema, airway bleeding, and previous or current tracheostomy. Twenty

  11. Video laryngoscopes and the obstetric airway.

    Science.gov (United States)

    Scott-Brown, S; Russell, R

    2015-05-01

    The pitfalls surrounding securing the airway in the obstetric patient are well documented. From Tunstall's original failed intubation drill onwards, there has been progress both in recognition of the difficulties of airway management in the pregnant patient and development of algorithms to enhance patient safety. Current trends in obstetric anaesthesia have resulted in a significant decrease in exposure of anaesthetists, especially trainees, to caesarean section under general anaesthesia, compounding the difficulties in safely managing the airway. Video laryngoscopes have recently appeared in airway algorithms. They improve glottic visualisation and are useful in the management of the difficult non-obstetric airway, including those in morbidly obese patients and in the setting of a rapid-sequence induction. There is growing interest in the potential use of video laryngoscopes in the obstetric population and as a teaching tool to maximise training opportunities. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Expression of the transient receptor potential channels TRPV1, TRPA1 and TRPM8 in mouse trigeminal primary afferent neurons innervating the dura

    Science.gov (United States)

    2012-01-01

    Background Migraine and other headache disorders affect a large percentage of the population and cause debilitating pain. Activation and sensitization of the trigeminal primary afferent neurons innervating the dura and cerebral vessels is a crucial step in the “headache circuit”. Many dural afferent neurons respond to algesic and inflammatory agents. Given the clear role of the transient receptor potential (TRP) family of channels in both sensing chemical stimulants and mediating inflammatory pain, we investigated the expression of TRP channels in dural afferent neurons. Methods We used two fluorescent tracers to retrogradely label dural afferent neurons in adult mice and quantified the abundance of peptidergic and non-peptidergic neuron populations using calcitonin gene-related peptide immunoreactivity (CGRP-ir) and isolectin B4 (IB4) binding as markers, respectively. Using immunohistochemistry, we compared the expression of TRPV1 and TRPA1 channels in dural afferent neurons with the expression in total trigeminal ganglion (TG) neurons. To examine the distribution of TRPM8 channels, we labeled dural afferent neurons in mice expressing farnesylated enhanced green fluorescent protein (EGFPf) from a TRPM8 locus. We used nearest-neighbor measurement to predict the spatial association between dural afferent neurons and neurons expressing TRPA1 or TRPM8 channels in the TG. Results and conclusions We report that the size of dural afferent neurons is significantly larger than that of total TG neurons and facial skin afferents. Approximately 40% of dural afferent neurons exhibit IB4 binding. Surprisingly, the percentage of dural afferent neurons containing CGRP-ir is significantly lower than those of total TG neurons and facial skin afferents. Both TRPV1 and TRPA1 channels are expressed in dural afferent neurons. Furthermore, nearest-neighbor measurement indicates that TRPA1-expressing neurons are clustered around a subset of dural afferent neurons. Interestingly, TRPM

  13. Vascularized nerve grafts for lower extremity nerve reconstruction.

    Science.gov (United States)

    Terzis, Julia K; Kostopoulos, Vasileios K

    2010-02-01

    Vascularized nerve grafts (VNG) were introduced in 1976 but since then, there have been no reports of their usage in lower extremity reconstruction systematically. The factors influencing outcomes as well as a comparison with conventional nerve grafts will be presented.Since 1981, 14 lower extremity nerve injuries in 12 patients have been reconstructed with VNG. Common peroneal nerve was injured in 12 and posterior tibial nerve in 5 patients. The level of the injury was at the knee or thigh. Twelve sural nerves were used as VNG with or without concomitant vascularized posterior calf fascia.All patients regained improved sensibility and adequate posterior tibial nerve function. For common peroneal nerve reconstructions, all patients with denervation time less than 6 months regained muscle strength of grade at least 4, even when long grafts were used for defects of 20 cm or more. Late cases, yielded inadequate muscle function even with the use of VNG.Denervation time of 6 months or less was critical for reconstruction with vascularized nerve graft. Not only the results were statistically significant compared with late cases, but also all early operated patients achieved excellent results. VNG are strongly recommended in traction avulsion injuries of the lower extremity with lengthy nerve damage.

  14. [Laryngeal tube II : alternative airway for children?].

    Science.gov (United States)

    Schalk, R; Scheller, B; Peter, N; Rosskopf, W; Byhahn, C; Zacharowski, K; Meininger, D

    2011-06-01

    Difficult airway situations both expected and unexpected, present major challenges to every anesthesiologist, especially in pediatric anesthesia. However, the integration of extraglottic airway devices, such as the laryngeal mask, into the algorithm of difficult airways has improved the handling of difficult airway situations. A device for establishing a supraglottic airway, the laryngeal tube (LT), was introduced in 1999. The LT is an extraglottic airway designed to secure a patent airway during either spontaneous breathing or controlled ventilation. The design of the device has been revised several times and a further development is the LTS II/LTS-D, which provides an additional channel for the insertion of a gastric drain tube. This article reports on the successful use of the LTS II in 12 children aged from 2 days to 6 years when endotracheal intubation, alternative mask or laryngeal mask ventilation failed. Use of the LTS II was associated with a high level of success, securing the airway when other techniques had failed. The potential advantage of the LTS II over the standard LT is an additional suction port, which allows gastric tube placement and can be used as an indirect indicator of correct placement. With a modified insertion technique using an Esmarch manoeuvre, placement was simple and fast to perform. In emergency situations when direct laryngoscopy fails or is too time-consuming the LTS II tube is recommended as an alternative device to secure the airway. As with all extraglottic airway devices, familiarity and clinical experience with the respective device and the corresponding insertion technique are essential for safe and successful use, especially in emergency situations.

  15. Arginase strongly impairs neuronal nitric oxide-mediated airway smooth muscle relaxation in allergic asthma

    Directory of Open Access Journals (Sweden)

    Zaagsma Johan

    2006-01-01

    Full Text Available Abstract Background Using guinea pig tracheal preparations, we have recently shown that endogenous arginase activity attenuates inhibitory nonadrenergic noncholinergic (iNANC nerve-mediated airway smooth muscle relaxation by reducing nitric oxide (NO production – due to competition with neuronal NO-synthase (nNOS for the common substrate, L-arginine. Furthermore, in a guinea pig model of allergic asthma, airway arginase activity is markedly increased after the early asthmatic reaction (EAR, leading to deficiency of agonist-induced, epithelium-derived NO and subsequent airway hyperreactivity. In this study, we investigated whether increased arginase activity after the EAR affects iNANC nerve-derived NO production and airway smooth muscle relaxation. Methods Electrical field stimulation (EFS; 150 mA, 4 ms, 4 s, 0.5 – 16 Hz-induced relaxation was measured in tracheal open-ring preparations precontracted to 30% with histamine in the presence of 1 μM atropine and 3 μM indomethacin. The contribution of NO to EFS-induced relaxation was assessed by the nonselective NOS inhibitor Nω-nitro-L-arginine (L-NNA, 100 μM, while the involvement of arginase activity in the regulation of EFS-induced NO production and relaxation was investigated by the effect of the specific arginase inhibitor Nω-hydroxy-nor-L-arginine (nor-NOHA, 10 μM. Furthermore, the role of substrate availability to nNOS was measured in the presence of exogenous L-arginine (5.0 mM. Results At 6 h after ovalbumin-challenge (after the EAR, EFS-induced relaxation (ranging from 3.2 ± 1.1% at 0.5 Hz to 58.5 ± 2.2% at 16 Hz was significantly decreased compared to unchallenged controls (7.1 ± 0.8% to 75.8 ± 0.7%; P P P Conclusion The results clearly demonstrate that increased arginase activity after the allergen-induced EAR contributes to a deficiency of iNANC nerve-derived NO and decreased airway smooth muscle relaxation, presumably via increased substrate competition with nNOS.

  16. Unilateral sixth nerve palsy.

    Science.gov (United States)

    Sotoodehnia, Mehran; Safaei, Arash; Rasooli, Fatemeh; Bahreini, Maryam

    2017-06-01

    The diagnosis of cerebral venous sinus thrombosis still remains a real challenge. Seizure, unusual headache with sudden onset, unexplained persistently unilateral vascular headache and neurologic deficit-which is difficult to be attributed to a vascular territory are some of the suggestive symptoms. An isolated sixth nerve palsy is discussed as a rare presentation for cerebral venous thrombosis. Following the extensive investigation to rule out other possible diagnoses, magnetic resonance venogram revealed the final etiology of sixth nerve palsy that was ipsilateral left transverse sinus thrombosis; therefore, anticoagulant treatment with low molecular weight heparin was administered. Rapid and accurate diagnosis and treatment cause to achieve excellent outcomes for most patients. Considering different clinical features, risk factors and high index of suspicion are helpful to reach the diagnosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. The oculomotor system of decapod cephalopods: eye muscles, eye muscle nerves, and the oculomotor neurons in the central nervous system.

    Science.gov (United States)

    Budelmann, B U; Young, J Z

    1993-04-29

    Fourteen extraocular eye muscles are described in the decapods Loligo and Sepioteuthis, and thirteen in Sepia; they are supplied by four eye muscle nerves. The main action of most of the muscles is a linear movement of the eyeball, only three muscles produce strong rotations. The arrangement, innervation and action of the decapod eye muscles are compared with those of the seven eye muscles and seven eye muscle nerves in Octopus. The extra muscles in decapods are attached to the anterior and superior faces of the eyes. At least, the anterior muscles, and presumably also the superior muscles, are concerned with convergent eye movements for binocular vision during fixation and capture of prey by the tentacles. The remaining muscles are rather similar in the two cephalopod groups. In decapods, the anterior muscles include conjunctive muscles; these cross the midline and each presumably moves both eyes at the same time during fixation. In the squids Loligo and Sepioteuthis there is an additional superior conjunctive muscle of perhaps similar function. Some of the anterior muscles are associated with a narrow moveable plate, the trochlear cartilage; it is attached to the eyeball by trochlear membranes. Centripetal cobalt fillings showed that all four eye muscle nerves have fibres that originate from somata in the ipsilateral anterior lateral pedal lobe, which is the oculomotor centre. The somata of the individual nerves show different but overlapping distributions. Bundles of small presumably afferent fibres were seen in two of the four nerves. They do not enter the anterior lateral pedal lobe but run to the ventral magnocellular lobe; some afferent fibres enter the brachio-palliovisceral connective and run perhaps as far as the palliovisceral lobe.

  18. Transcutaneous vagus nerve stimulation for the treatment of depression: a study protocol for a double blinded randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Rong Pei-Jing

    2012-12-01

    Full Text Available Abstract Background Depressive disorders are the most common form of mental disorders in community and health care settings. Unfortunately, the treatment of Major Depressive Disorder (MDD is far from satisfactory. Vagus nerve stimulation (VNS is a relatively new and promising physical treatment for depressive disorders. One particularly appealing element of VNS is the long-term benefit in mood regulation. However, because this intervention involves surgery, perioperative risks, and potentially significant side effects, this treatment has been limited to those patients with treatment-resistant depression who have failed medication trials and exhausted established somatic treatments for major depression, due to intolerance or lack of response. This double-blinded randomized clinical trial aims to overcome these limitations by introducing a novel method of stimulating superficial branches of the vagus nerve on the ear to treat MDD. The rationale is that direct stimulation of the afferent nerve fibers on the ear area with afferent vagus nerve distribution should produce a similar effect as classic VNS in reducing depressive symptoms without the burden of surgical intervention. Design One hundred twenty cases (60 males of volunteer patients with mild and moderate depression will be randomly divided into transcutaneous vagus nerve stimulation group (tVNS and sham tVNS group. The treatment period lasts 4 months and all clinical and physiological measurements are acquired at the beginning and the end of the treatment period. Discussion This study has the potential to significantly extend the application of VNS treatment for MDD and other disorders (including epilepsy, bipolar disorder, and morbid obesity, resulting in direct benefit to the patients suffering from these highly prevalent disorders. In addition, the results of this double-blinded clinical trial will shed new light on our understanding of acupuncture point specificity, and development of

  19. Optic nerve hypoplasia

    Directory of Open Access Journals (Sweden)

    Savleen Kaur

    2013-01-01

    Full Text Available Optic nerve hypoplasia (ONH is a congenital anomaly of the optic disc that might result in moderate to severe vision loss in children. With a vast number of cases now being reported, the rarity of ONH is obviously now refuted. The major aspects of ophthalmic evaluation of an infant with possible ONH are visual assessment, fundus examination, and visual electrophysiology. Characteristically, the disc is small, there is a peripapillary double-ring sign, vascular tortuosity, and thinning of the nerve fiber layer. A patient with ONH should be assessed for presence of neurologic, radiologic, and endocrine associations. There may be maternal associations like premature births, fetal alcohol syndrome, maternal diabetes. Systemic associations in the child include endocrine abnormalities, developmental delay, cerebral palsy, and seizures. Besides the hypoplastic optic nerve and chiasm, neuroimaging shows abnormalities in ventricles or white- or gray-matter development, septo-optic dysplasia, hydrocephalus, and corpus callosum abnormalities. There is a greater incidence of clinical neurologic abnormalities in patients with bilateral ONH (65% than patients with unilateral ONH. We present a review on the available literature on the same to urge caution in our clinical practice when dealing with patients with ONH. Fundus photography, ocular coherence tomography, visual field testing, color vision evaluation, neuroimaging, endocrinology consultation with or without genetic testing are helpful in the diagnosis and management of ONH. (Method of search: MEDLINE, PUBMED.

  20. Thrombospondins 1 and 2 are important for afferent synapse formation and function in the inner ear.

    Science.gov (United States)

    Mendus, Diana; Sundaresan, Srividya; Grillet, Nicolas; Wangsawihardja, Felix; Leu, Rose; Müller, Ulrich; Jones, Sherri M; Mustapha, Mirna

    2014-04-01

    Thrombospondins (TSPs) constitute a family of secreted extracellular matrix proteins that have been shown to be involved in the formation of synapses in the central nervous system. In this study, we show that TSP1 and TSP2 are expressed in the cochlea, and offer the first description of their putative roles in afferent synapse development and function in the inner ear. We examined mice with deletions of TSP1, TSP2 and both (TSP1/TSP2) for inner ear development and function. Immunostaining for synaptic markers indicated a significant decrease in the number of formed afferent synapses in the cochleae of TSP2 and TSP1/TSP2 knockout (KO) mice at postnatal day (P)29. In functional studies, TSP2 and TSP1/TSP2 KO mice showed elevated auditory brainstem response (ABR) thresholds as compared with wild-type littermates, starting at P15, with the most severe phenotype being seen for TSP1/TSP2 KO mice. TSP1/TSP2 KO mice also showed reduced wave I amplitudes of ABRs and vestibular evoked potentials, suggesting synaptic dysfunction in both the auditory and vestibular systems. Whereas ABR thresholds in TSP1 KO mice were relatively unaffected at early ages, TSP1/TSP2 KO mice showed the most severe phenotype among all of the genotypes tested, suggesting functional redundancy between the two genes. On the basis of the above results, we propose that TSPs play an important role in afferent synapse development and function of the inner ear. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  1. Endocannabinoids and prostaglandins both contribute to GnRH neuron-GABAergic afferent local feedback circuits

    Science.gov (United States)

    Glanowska, Katarzyna M.

    2011-01-01

    Gonadotropin-releasing hormone (GnRH) neurons form the final common pathway for central control of fertility. Regulation of GnRH neurons by long-loop gonadal steroid feedback through steroid receptor-expressing afferents such as GABAergic neurons is well studied. Recently, local central feedback circuits regulating GnRH neurons were identified. GnRH neuronal depolarization induces short-term inhibition of their GABAergic afferents via a mechanism dependent on metabotropic glutamate receptor (mGluR) activation. GnRH neurons are enveloped in astrocytes, which express mGluRs. GnRH neurons also produce endocannabinoids, which can be induced by mGluR activation. We hypothesized the local GnRH-GABA circuit utilizes glia-derived and/or cannabinoid mechanisms and is altered by steroid milieu. Whole cell voltage-clamp was used to record GABAergic postsynaptic currents (PSCs) from GnRH neurons before and after action potential-like depolarizations were mimicked. In GnRH neurons from ovariectomized (OVX) mice, this depolarization reduced PSC frequency. This suppression was blocked by inhibition of prostaglandin synthesis with indomethacin, by a prostaglandin receptor antagonist, or by a specific glial metabolic poison, together suggesting the postulate that prostaglandins, potentially glia-derived, play a role in this circuit. This circuit was also inhibited by a CB1 receptor antagonist or by blockade of endocannabinoid synthesis in GnRH neurons, suggesting an endocannabinoid element, as well. In females, local circuit inhibition persisted in androgen-treated mice but not in estradiol-treated mice or young ovary-intact mice. In contrast, local circuit inhibition was present in gonad-intact males. These data suggest GnRH neurons interact with their afferent neurons using multiple mechanisms and that these local circuits can be modified by both sex and steroid feedback. PMID:21917995

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

    International Nuclear Information System (INIS)

    Nieoullon, A.; Dusticier, N.

    1982-01-01

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

  3. Contribution of afferent feedback to the soleus muscle activity during human locomotion

    DEFF Research Database (Denmark)

    Nazarena, Mazzaro; Grey, Michael James; Sinkjær, Thomas

    2005-01-01

    generated gradual increments and decrements, respectively, in the ongoing SOL EMG. We exercised care to ensure that the imposed ankle movements were too slow to elicit distinct burst-like stretch reflex responses that have been investigated previously. The increased SOL EMG after the dorsiflexion......During the stance phase of the human step cycle, the ankle undergoes a natural dorsiflexion that stretches the soleus muscle. The afferent feedback resulting from this stretch enhances the locomotor drive. In this study a robotic actuator was used to slightly enhance or reduce the natural ankle...

  4. Decreased contribution from afferent feedback to the soleus muscle during walking in patients with spastic stroke

    DEFF Research Database (Denmark)

    Mazzaro, Nazarena; Nielsen, Jørgen Feldbæk; Grey, Michael James

    2007-01-01

    attached to the foot and leg was used to apply 3 types of ankle perturbations during treadmill walking. First, fast dorsiflexion perturbations were applied to elicit stretch reflexes in the SOL muscle. The SOL short-latency stretch reflex was facilitated in the patients (1.4 +/- 0.3) compared...... by the Ashworth score. These results indicate that although the stretch reflex response is facilitated during spastic gait, the contribution of afferent feedback to the ongoing locomotor SOL activity is depressed in patients with spastic stroke....

  5. Prostaglandin potentiates 5-HT responses in stomach and ileum innervating visceral afferent sensory neurons

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sojin; Jin, Zhenhua; Lee, Goeun [Department of Physiology, School of Medicine, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Park, Yong Seek; Park, Cheung-Seog [Department of Microbiology, School of Medicine, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Jin, Young-Ho, E-mail: jinyh@khu.ac.kr [Department of Physiology, School of Medicine, Kyung Hee University, Seoul 130-701 (Korea, Republic of)

    2015-01-02

    Highlights: • Prostaglandin E2 (PGE{sub 2}) effect was tested on visceral afferent neurons. • PGE{sub 2} did not evoke response but potentiated serotonin (5-HT) currents up to 167%. • PGE{sub 2}-induced potentiation was blocked by E-prostanoid type 4 receptors antagonist. • PGE{sub 2} effect on 5-HT response was also blocked by protein kinase A inhibitor KT5720. • Thus, PGE{sub 2} modulate visceral afferent neurons via synergistic signaling with 5-HT. - Abstract: Gastrointestinal disorder is a common symptom induced by diverse pathophysiological conditions that include food tolerance, chemotherapy, and irradiation for therapy. Prostaglandin E{sub 2} (PGE{sub 2}) level increase was often reported during gastrointestinal disorder and prostaglandin synthetase inhibitors has been used for ameliorate the symptoms. Exogenous administration of PGE{sub 2} induces gastrointestinal disorder, however, the mechanism of action is not known. Therefore, we tested PGE{sub 2} effect on visceral afferent sensory neurons of the rat. Interestingly, PGE{sub 2} itself did not evoked any response but enhanced serotonin (5-HT)-evoked currents up to 167% of the control level. The augmented 5-HT responses were completely inhibited by a 5-HT type 3 receptor antagonist, ondansetron. The PGE{sub 2}-induced potentiation were blocked by a selective E-prostanoid type4 (EP{sub 4}) receptors antagonist, L-161,982, but type1 and 2 receptor antagonist AH6809 has no effect. A membrane permeable protein kinase A (PKA) inhibitor, KT5720 also inhibited PGE{sub 2} effects. PGE{sub 2} induced 5-HT current augmentation was observed on 15% and 21% of the stomach and ileum projecting neurons, respectively. Current results suggest a synergistic signaling in visceral afferent neurons underlying gastrointestinal disorder involving PGE{sub 2} potentiation of 5-HT currents. Our findings may open a possibility for screen a new type drugs with lower side effects than currently using steroidal prostaglandin

  6. Effects of levodropropizine on vagal afferent C-fibres in the cat.

    OpenAIRE

    Shams, H.; Daffonchio, L.; Scheid, P.

    1996-01-01

    1. Levodropropizine (LVDP) is an effective antitussive drug. Its effects on single-unit discharge of vagal afferent C-fibres were tested in anaesthetized cats to assess whether an inhibition of vagal C-fibres is involved in its antitussive properties. Vagal C-fibres, identified by their response to phenylbiguanide (PBG), were recorded via suction electrodes from the distal part of the cut vagus. Based on their response to lung inflation, C-fibres were classified as pulmonary (19 fibres) or no...

  7. Intracellular signalling pathways in the vasoconstrictor response of mouse afferent arterioles to adenosine

    DEFF Research Database (Denmark)

    Hansen, Pernille B. Lærkegaard; Friis, Ulla Glenert; Uhrenholt, Torben Rene

    2007-01-01

    of calcium from the sarcoplasmic reticulum (SR), stimulated presumably by IP(3), is involved in the adenosine contraction mechanism of the afferent arteriole. In agreement with this notion is the observation that 2 aminoethoxydiphenyl borate (100 microM) blocked the adenosine-induced constriction whereas...... was abolished by IAA-94. Furthermore, the vasoconstriction caused by adenosine was significantly inhibited by 5 microM nifedipine (control 8.3 +/- 0.2 microM, ado 3.6 +/- 0.6 microM, ado + nifedipine 6.8 +/- 0.2 microM) suggesting involvement of voltage-dependent calcium channels. CONCLUSION: We conclude...

  8. Post-extubation airway obstruction. Literature review

    Directory of Open Access Journals (Sweden)

    Álvaro SÁNCHEZ-TABERNERO

    2017-03-01

    Full Text Available Introduction and objective: airway obstruction after extubation in any surgery is a critical event with low incidence, which may require reintubation or tracheostomy, which often otolaryngologist is required. Objective: To determine the prevalence of BVA and its causes through systematic literature review. Method: Literature review in PubMed, Scopus and Cochrane clinical trials, meta-analysis, reviews and case series and control over airway obstruction after extubation that requires reintubation in adults. Results: 6 studies and one clinical practice guidelines were selected. The most common cause of extubation failure is blocking the airway for various reasons (pharyngeal muscle weakness residual effect -often farmacologycal-, laryngospasm, vocal cord paralysis, edema of upper respiratory tract, cervical postoperative hematoma, foreign bodies or secretions. Most cases of re-intubation occurred within 2 hours after extubation. Conclusions: The most common cause of failure after general anesthesia extubation is blocking the airway generally caused by residual neuromuscular blocking effect. Airway obstruction risk increases in airway and head and neck surgery. Difficult intubation guidlines have improved performance and reduced adverse events and similar strategies must be implemented in extubation. The procedure extubation and reintubation should be documented. Working groups airway must be multidisciplinary and include specialists in otolaryngology.

  9. Color analysis of the human airway wall

    Science.gov (United States)

    Gopalakrishnan, Deepa; McLennan, Geoffrey; Donnelley, Martin; Delsing, Angela; Suter, Melissa; Flaherty, Dawn; Zabner, Joseph; Hoffman, Eric A.; Reinhardt, Joseph M.

    2002-04-01

    A bronchoscope can be used to examine the mucosal surface of the airways for abnormalities associated with a variety of lung diseases. The diagnosis of these abnormalities through the process of bronchoscopy is based, in part, on changes in airway wall color. Therefore it is important to characterize the normal color inside the airways. We propose a standardized method to calibrate the bronchoscopic imaging system and to tabulate the normal colors of the airway. Our imaging system consists of a Pentium PC and video frame grabber, coupled with a true color bronchoscope. The calibration procedure uses 24 standard color patches. Images of these color patches at three different distances (1, 1.5, and 2 cm) were acquired using the bronchoscope in a darkened room, to assess repeatability and sensitivity to illumination. The images from the bronchoscope are in a device-dependent Red-Green-Blue (RGB) color space, which was converted to a tri-stimulus image and then into a device-independent color space sRGB image by a fixed polynomial transformation. Images were acquired from five normal human volunteer subjects, two cystic fibrosis (CF) patients and one normal heavy smoker subject. The hue and saturation values of regions within the normal airway were tabulated and these values were compared with the values obtained from regions within the airways of the CF patients and the normal heavy smoker. Repeated measurements of the same region in the airways showed no measurable change in hue or saturation.

  10. Nurses' Awareness about Principles of Airway Suctioning.

    Science.gov (United States)

    Heidari, Mohammad; Shahbazi, Sara

    2017-08-01

    Airway suctioning is one of the most common interventions for patients with respiratory disorders and having adequate knowledge in implementing this technique is quite crucial for nurses. To assess the nurses' awareness about principles of airway suctioning. This study was a cross-sectional study done on 85 staff nurses' in Vali-Asr hospital. Sampling was based on census data collection. A researcher made questionnaire was used for assessment of nurses' awareness about the principles of airway suctioning. The validity and reliability (Cronbach's alpha=0.78) of the questionnaire have been examined and proved. The level of nurses' awareness about airway suctioning was measured based on the questionnaire that includes demographic and specialty information in the form of eight questions of 3-selection-item. The maximum and minimum score of knowledge ranged between 0-8. The data obtained was statistically analysed using SPSS software Version 16.0 and was analysed using descriptive statistics and Pearson correlation coefficient. The results reveal that the nurses' awareness about principles of airway suctioning was average. There was a significant association between knowledge and gender of nurses (pprinciples of airway suctioning was more than men. The results indicate that nurses' awareness of airway suctioning technique was in an average state. Considering the importance of this technique and the effects this technique has on the patients' haemodynamic status, we recommend in-service courses.

  11. Nerves and nerve endings in the skin of tropical cattle.

    Science.gov (United States)

    Amakiri, S F; Ozoya, S E; Ogunnaike, P O

    1978-01-01

    The nerves and nerve endings in the skin of tropical cattle were studied using histological and histochemical techniques. Many nerve trunks and fibres were present in the reticular and papillary dermis in both hairy and non-hairy skin sites. In non-hairy skin locations such as the muzzle and lower lip, encapsulated endings akin to Krause and Ruffini end bulbs, which arise from myelinated nerve trunks situated lower down the dermis were observed at the upper papillary layer level. Some fibre trunks seen at this level extended upwards to terminate within dermal papillae as bulb-shaped longitudinally lamellated Pacinian-type endings, while other onion-shaped lamellated nerve structures were located either within dermal papillae or near the dermo-epidermal area. Intraepidermal free-ending nerve fibres, appearing non-myelinated were observed in areas with thick epidermis. Intraepidermal free-ending nerve fibres, appearing non-myelinated were observed in areas with thick epidermis. On hairy skin sites, however, organized nerve endings or intraepidermal nerve endings were not readily identifiable.

  12. Peripheral Nerve Injury: Stem Cell Therapy and Peripheral Nerve Transfer.

    Science.gov (United States)

    Sullivan, Robert; Dailey, Travis; Duncan, Kelsey; Abel, Naomi; Borlongan, Cesario V

    2016-12-14

    Peripheral nerve injury can lead to great morbidity in those afflicted, ranging from sensory loss, motor loss, chronic pain, or a combination of deficits. Over time, research has investigated neuronal molecular mechanisms implicated in nerve damage, classified nerve injury, and developed surgical techniques for treatment. Despite these advancements, full functional recovery remains less than ideal. In this review, we discuss historical aspects of peripheral nerve injury and introduce nerve transfer as a therapeutic option, as well as an adjunct therapy to transplantation of Schwann cells and their stem cell derivatives for repair of the damaged nerve. This review furthermore, will provide an elaborated discussion on the sources of Schwann cells, including sites to harvest their progenitor and stem cell lines. This reflects the accessibility to an additional, concurrent treatment approach with nerve transfers that, predicated on related research, may increase the efficacy of the current approach. We then discuss the experimental and clinical investigations of both Schwann cells and nerve transfer that are underway. Lastly, we provide the necessary consideration that these two lines of therapeutic approaches should not be exclusive, but conversely, should be pursued as a combined modality given their mutual role in peripheral nerve regeneration.

  13. Peripheral Nerve Injury: Stem Cell Therapy and Peripheral Nerve Transfer

    Directory of Open Access Journals (Sweden)

    Robert Sullivan

    2016-12-01

    Full Text Available Peripheral nerve injury can lead to great morbidity in those afflicted, ranging from sensory loss, motor loss, chronic pain, or a combination of deficits. Over time, research has investigated neuronal molecular mechanisms implicated in nerve damage, classified nerve injury, and developed surgical techniques for treatment. Despite these advancements, full functional recovery remains less than ideal. In this review, we discuss historical aspects of peripheral nerve injury and introduce nerve transfer as a therapeutic option, as well as an adjunct therapy to transplantation of Schwann cells and their stem cell derivatives for repair of the damaged nerve. This review furthermore, will provide an elaborated discussion on the sources of Schwann cells, including sites to harvest their progenitor and stem cell lines. This reflects the accessibility to an additional, concurrent treatment approach with nerve transfers that, predicated on related research, may increase the efficacy of the current approach. We then discuss the experimental and clinical investigations of both Schwann cells and nerve transfer that are underway. Lastly, we provide the necessary consideration that these two lines of therapeutic approaches should not be exclusive, but conversely, should be pursued as a combined modality given their mutual role in peripheral nerve regeneration.

  14. Thyroid hormone is required for pruning, functioning and long-term maintenance of afferent inner hair cell synapses.

    Science.gov (United States)

    Sundaresan, Srividya; Kong, Jee-Hyun; Fang, Qing; Salles, Felipe T; Wangsawihardja, Felix; Ricci, Anthony J; Mustapha, Mirna

    2016-01-01

    Functional maturation of afferent synaptic connections to inner hair cells (IHCs) involves pruning of excess synapses formed during development, as well as the strengthening and survival of the retained synapses. These events take place during the thyroid hormone (TH)-critical period of cochlear development, which is in the perinatal period for mice and in the third trimester for humans. Here, we used the hypothyroid Snell dwarf mouse (Pit1(dw)) as a model to study the role of TH in afferent type I synaptic refinement and functional maturation. We observed defects in afferent synaptic pruning and delays in calcium channel clustering in the IHCs of Pit1(dw) mice. Nevertheless, calcium currents and capacitance reached near normal levels in Pit1(dw) IHCs by the age of onset of hearing, despite the excess number of retained synapses. We restored normal synaptic pruning in Pit1(dw) IHCs by supplementing with TH from postnatal day (P)3 to P8, establishing this window as being critical for TH action on this process. Afferent terminals of older Pit1(dw) IHCs showed evidence of excitotoxic damage accompanied by a concomitant reduction in the levels of the glial glutamate transporter, GLAST. Our results indicate that a lack of TH during a critical period of inner ear development causes defects in pruning and long-term homeostatic maintenance of afferent synapses. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  15. Educating the Educator: Teaching Airway Adjunct Techniques in Athletic Training

    Science.gov (United States)

    Berry, David C.; Seitz, S. Robert

    2011-01-01

    The 5th edition of the "Athletic Training Education Competencies" ("Competencies") now requires athletic training educators (ATEs) to introduce into the curriculum various types of airway adjuncts including: (1) oropharyngeal airways (OPA), (2) nasopharyngeal airways (NPA), (3) supraglottic airways (SGA), and (4) suction. The addition of these…

  16. Nasal continuous positive airway pressure

    DEFF Research Database (Denmark)

    Scholze, Alexandra; Lamwers, Stephanie; Tepel, Martin

    2012-01-01

    Obstructive sleep apnoea (OSA) is linked to increased cardiovascular risk. This risk can be reduced by nasal continuous positive airway pressure (nCPAP) treatment. As OSA is associated with an increase of several vasoconstrictive factors, we investigated whether nCPAP influences the digital volume...... pulse wave. We performed digital photoplethysmography during sleep at night in 94 consecutive patients who underwent polysomnography and 29 patients treated with nCPAP. Digital volume pulse waves were obtained independently of an investigator and were quantified using an algorithm for continuous.......01; n = 94) and the arousal index (Spearman correlation, r = 0.21; p CPAP treatment, the AHI was significantly reduced from 27 ± 3 events · h(-1) to 4 ± 2 events · h(-1) (each n = 29; p

  17. Magnetic resonance imaging of the pediatric airway

    International Nuclear Information System (INIS)

    Auringer, S.T.; Bisset, G.S. III; Myer, C.M.

    1991-01-01

    Evaluation of the pediatric airway is often complex and may require multiple imaging techniques and invasive procedures. We performed magnetic resonance (MR) imaging of the airway in 34 children with clinical evidence of chronic airway obstruction and compared MR findings with those obtained by surgery and/or endoscopy. MR diagnoses included vascular compression in 15 patients, primary tracheomalacic states in 12 patients, and mediastinal masses in 4 patients. Findings were normal for 3 patients. The MR findings were in agreement with the endoscopic findings in 25 to 28 cases and in agreement with the surgical findings in 21 to 21 cases. (orig./GDG)

  18. Predictors of Airway Hyperresponsiveness in Elite Athletes

    DEFF Research Database (Denmark)

    Toennesen, Louise L; Porsbjerg, Celeste; Pedersen, Lars

    2015-01-01

    INTRODUCTION: Elite athletes frequently experience asthma and airway hyperresponsiveness (AHR). We aimed to investigate predictors of airway pathophysiology in a group of unselected elite summer-sport athletes, training for the summer 2008 Olympic Games, including markers of airway inflammation......, systemic inflammation, and training intensity. METHODS: Fifty-seven Danish elite summer-sport athletes with and without asthma symptoms all gave a blood sample for measurements of high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor alpha (TNF...

  19. Nerve cross-bridging to enhance nerve regeneration in a rat model of delayed nerve repair.

    Directory of Open Access Journals (Sweden)

    Tessa Gordon

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

  20. Eosinophilic airway inflammation in asthmatic patients is associated with an altered airway microbiome

    DEFF Research Database (Denmark)

    Sverrild, Asger; Kiilerich, Pia; Brejnrod, Asker Daniel

    2017-01-01

    of eosinophilic airway inflammation correlates with variations in the microbiome across asthmatic patients, whereas neutrophilic airway inflammation does not. This warrants further investigation on molecular pathways involved in both patients with eosinophilic and those with noneosinophilic asthma.......BACKGROUND: Asthmatic patients have higher microbiome diversity and an altered composition, with more Proteobacteria and less Bacteroidetes compared with healthy control subjects. Studies comparing airway inflammation and the airway microbiome are sparse, especially in subjects not receiving anti......-inflammatory treatment. OBJECTIVE: We sought to describe the relationship between the airway microbiome and patterns of airway inflammation in steroid-free patients with asthma and healthy control subjects. METHODS: Bronchoalveolar lavage fluid was collected from 23 steroid-free nonsmoking patients with asthma and 10...

  1. Airway Remodelling in Asthma: From Benchside to Clinical Practice

    Directory of Open Access Journals (Sweden)

    Céline Bergeron

    2010-01-01

    Full Text Available Airway remodelling refers to the structural changes that occur in both large and small airways relevant to miscellaneous diseases including asthma. In asthma, airway structural changes include subepithelial fibrosis, increased smooth muscle mass, gland enlargement, neovascularization and epithelial alterations. Although controversial, airway remodelling is commonly attributed to an underlying chronic inflammatory process. These remodelling changes contribute to thickening of airway walls and, consequently, lead to airway narrowing, bronchial hyper-responsiveness, airway edema and mucous hypersecretion. Airway remodelling is associated with poor clinical outcomes among asthmatic patients. Early diagnosis and prevention of airway remodelling has the potential to decrease disease severity, improve control and prevent disease expression. The relationship between structural changes and clinical and functional abnormalities clearly deserves further investigation. The present review briefly describes the characteristic features of airway remodelling observed in asthma, its clinical consequences and relevance for physicians, and its modulation by therapeutic approaches used in the treatment of asthmatic patients.

  2. The Role of 5-HT3 Receptors in Signaling from Taste Buds to Nerves.

    Science.gov (United States)

    Larson, Eric D; Vandenbeuch, Aurelie; Voigt, Anja; Meyerhof, Wolfgang; Kinnamon, Sue C; Finger, Thomas E

    2015-12-02

    Activation of taste buds triggers the release of several neurotransmitters, including ATP and serotonin (5-hydroxytryptamine; 5-HT). Type III taste cells release 5-HT directly in response to acidic (sour) stimuli and indirectly in response to bitter and sweet tasting stimuli. Although ATP is necessary for activation of nerve fibers for all taste stimuli, the role of 5-HT is unclear. We investigated whether gustatory afferents express functional 5-HT3 receptors and, if so, whether these receptors play a role in transmission of taste information from taste buds to nerves. In mice expressing GFP under the control of the 5-HT(3A) promoter, a subset of cells in the geniculate ganglion and nerve fibers in taste buds are GFP-positive. RT-PCR and in situ hybridization confirmed the presence of 5-HT(3A) mRNA in the geniculate ganglion. Functional studies show that only those geniculate ganglion cells expressing 5-HT3A-driven GFP respond to 10 μM 5-HT and this response is blocked by 1 μM ondansetron, a 5-HT3 antagonist, and mimicked by application of 10 μM m-chlorophenylbiguanide, a 5-HT3 agonist. Pharmacological blockade of 5-HT3 receptors in vivo or genetic deletion of the 5-HT3 receptors reduces taste nerve responses to acids and other taste stimuli compared with controls, but only when urethane was used as the anesthetic. We find that anesthetic levels of pentobarbital reduce taste nerve responses apparently by blocking the 5-HT3 receptors. Our results suggest that 5-HT released from type III cells activates gustatory nerve fibers via 5-HT3 receptors, accounting for a significant proportion of the neural taste response. Copyright © 2015 the authors 0270-6474/15/3515984-12$15.00/0.

  3. Common peroneal nerve entrapment with the communication ...

    African Journals Online (AJOL)

    Sciatic nerve divides into tibial nerve and common peroneal nerve at the level of superior angle of popliteal fossa and variations in its branching pattern are common. The most common nerve entrapment syndrome in the lower limbs is common peroneal nerve entrapment at fibular head. Invariably it can also be trapped in ...

  4. Airway resistance at maximum inhalation as a marker of asthma and airway hyperresponsiveness

    Directory of Open Access Journals (Sweden)

    O'Connor George T

    2011-07-01

    Full Text Available Abstract Background Asthmatics exhibit reduced airway dilation at maximal inspiration, likely due to structural differences in airway walls and/or functional differences in airway smooth muscle, factors that may also increase airway responsiveness to bronchoconstricting stimuli. The goal of this study was to test the hypothesis that the minimal airway resistance achievable during a maximal inspiration (Rmin is abnormally elevated in subjects with airway hyperresponsiveness. Methods The Rmin was measured in 34 nonasthmatic and 35 asthmatic subjects using forced oscillations at 8 Hz. Rmin and spirometric indices were measured before and after bronchodilation (albuterol and bronchoconstriction (methacholine. A preliminary study of 84 healthy subjects first established height dependence of baseline Rmin values. Results Asthmatics had a higher baseline Rmin % predicted than nonasthmatic subjects (134 ± 33 vs. 109 ± 19 % predicted, p = 0.0004. Sensitivity-specificity analysis using receiver operating characteristic curves indicated that baseline Rmin was able to identify subjects with airway hyperresponsiveness (PC20 min % predicted, FEV1 % predicted, and FEF25-75 % predicted, respectively. Also, 80% of the subjects with baseline Rmin min > 145% predicted had hyperresponsive airways, regardless of clinical classification as asthmatic or nonasthmatic. Conclusions These findings suggest that baseline Rmin, a measurement that is easier to perform than spirometry, performs as well as or better than standard spirometric indices in distinguishing subjects with airway hyperresponsiveness from those without hyperresponsive airways. The relationship of baseline Rmin to asthma and airway hyperresponsiveness likely reflects a causal relation between conditions that stiffen airway walls and hyperresponsiveness. In conjunction with symptom history, Rmin could provide a clinically useful tool for assessing asthma and monitoring response to treatment.

  5. Aplasia of the optic nerve.

    Science.gov (United States)

    Tang, Daniel C W; Man, Eric M W; Cheng, Sunny C S

    2015-08-01

    Aplasia of the optic nerve is an extraordinarily rare congenital anomaly that affects one or both optic nerves and is associated with the absence of the central retinal vessel and retinal ganglion cells. We report a case of unilateral optic nerve aplasia in a 4-month-old infant who was found to have left microphthalmos on routine postnatal checkup. Family history, antenatal history, and systemic evaluation were unremarkable. Magnetic resonance imaging showed absent left optic nerve with left microphthalmos. The optic chiasm was present and slightly deviated towards the right side. The remaining cerebral and ocular structures were normal.

  6. Comprehensive airway management of patients with maxillofacial trauma.

    Science.gov (United States)

    Kellman, Robert M; Losquadro, William D

    2008-11-01

    Airway management in patients with maxillofacial trauma is complicated by injuries to routes of intubation, and the surgeon is frequently asked to secure the airway. Airway obstruction from hemorrhage, tissue prolapse, or edema may require emergent intervention for which multiple intubation techniques exist. Competing needs for both airway and surgical access create intraoperative conflicts during repair of maxillofacial fractures. Postoperatively, edema and maxillomandibular fixation place the patient at risk for further airway compromise.

  7. The medical implications of gastrointestinal vagal afferent pathways in nausea and vomiting.

    Science.gov (United States)

    Horn, Charles C

    2014-01-01

    Nausea and vomiting are biological systems for defense against food poisoning that are also provoked by numerous drugs (e.g., chemotherapy, anesthesia) and chronic diseases (e.g., cancer, diabetic gastroparesis). The sensory pathways that stimulate nausea and vomiting include vestibular, area postrema, and forebrain inputs, but gastrointestinal vagal afferent fibers arguably play the most prominent role as a first-line defense. Vagal sensory neurons detect toxins that enter the gastrointestinal lumen and transmit information to the hindbrain, leading to nausea (an unconditioned stimulus that serves to facilitate the avoidance of offending foods) and vomiting (a mechanism to clear contents from the stomach). Despite the major importance of these systems to human physiology, progress on the biological basis of nausea and vomiting has been slow - partly because laboratory rats and mice, which represent the largest thrust of preclinical biomedical research, lack a vomiting reflex (although they appear to have indices of nausea, e.g., conditioned food aversion). Several established models are a mainstay of preclinical nausea and vomiting research in academia and pharmaceutical companies, including the dog, cat, ferret, and musk shrew. An argument is made for broader testing across species since each model possesses often unique experimental advantages and sensitivity to emetic and antiemetic agents. This review focuses on the state of knowledge on the neural pathways for nausea and vomiting, behavioral indices of nausea used in preclinical models, role of vagal afferent fibers, current antiemetic and antinausea treatments, and potential future directions.

  8. Liver Afferents Contribute to Water Drinking-Induced Sympathetic Activation in Human Subjects: A Clinical Trial

    Science.gov (United States)

    May, Marcus; Gueler, Faikah; Barg-Hock, Hannelore; Heiringhoff, Karl-Heinz; Engeli, Stefan; Heusser, Karsten; Diedrich, André; Brandt, André; Strassburg, Christian P.; Tank, Jens; Sweep, Fred C. G. J.; Jordan, Jens

    2011-01-01

    Water drinking acutely increases sympathetic activity in human subjects. In animals, the response appears to be mediated through transient receptor potential channel TRPV4 activation on osmosensitive hepatic spinal afferents, described as osmopressor response. We hypothesized that hepatic denervation attenuates water drinking-induced sympathetic activation. We studied 20 liver transplant recipients (44±2.6 years, 1.2±0.1 years post transplant) as model of hepatic denervation and 20 kidney transplant recipients (43±2.6 years, 0.8±0.1 years post transplant) as immunosuppressive drug matched control group. Before and after 500 ml water ingestion, we obtained venous blood samples for catecholamine analysis. We also monitored brachial and finger blood pressure, ECG, and thoracic bioimpedance. Plasma norepinephrine concentration had changed by 0.01±0.07 nmol/l in liver and by 0.21±0.07 nmol/l in kidney transplant recipients (pwater drinking. While blood pressure and systemic vascular resistance increased in both groups, the responses tended to be attenuated in liver transplant recipients. Our findings support the idea that osmosensitive hepatic afferents are involved in water drinking-induced sympathetic activation in human subjects. Trial Registration ClinicalTrials.gov NCT01237431 PMID:22016786

  9. Acetazolamide potentiates the afferent drive to prefrontal cortex in vivo.

    Science.gov (United States)

    Bueno-Junior, Lezio S; Ruggiero, Rafael N; Rossignoli, Matheus T; Del Bel, Elaine A; Leite, Joao P; Uchitel, Osvaldo D

    2017-01-01

    The knowledge on real-time neurophysiological effects of acetazolamide is still far behind the wide clinical use of this drug. Acetazolamide - a carbonic anhydrase inhibitor - has been shown to affect the neuromuscular transmission, implying a pH-mediated influence on the central synaptic transmission. To start filling such a gap, we chose a central substrate: hippocampal-prefrontal cortical projections; and a synaptic phenomenon: paired-pulse facilitation (a form of synaptic plasticity) to probe this drug's effects on interareal brain communication in chronically implanted rats. We observed that systemic acetazolamide potentiates the hippocampal-prefrontal paired-pulse facilitation. In addition to this field electrophysiology data, we found that acetazolamide exerts a net inhibitory effect on prefrontal cortical single-unit firing. We propose that systemic acetazolamide reduces the basal neuronal activity of the prefrontal cortex, whereas increasing the afferent drive it receives from the hippocampus. In addition to being relevant to the clinical and side effects of acetazolamide, these results suggest that exogenous pH regulation can have diverse impacts on afferent signaling across the neocortex. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  10. Liver afferents contribute to water drinking-induced sympathetic activation in human subjects: a clinical trial.

    Directory of Open Access Journals (Sweden)

    Marcus May

    Full Text Available Water drinking acutely increases sympathetic activity in human subjects. In animals, the response appears to be mediated through transient receptor potential channel TRPV4 activation on osmosensitive hepatic spinal afferents, described as osmopressor response. We hypothesized that hepatic denervation attenuates water drinking-induced sympathetic activation. We studied 20 liver transplant recipients (44±2.6 years, 1.2±0.1 years post transplant as model of hepatic denervation and 20 kidney transplant recipients (43±2.6 years, 0.8±0.1 years post transplant as immunosuppressive drug matched control group. Before and after 500 ml water ingestion, we obtained venous blood samples for catecholamine analysis. We also monitored brachial and finger blood pressure, ECG, and thoracic bioimpedance. Plasma norepinephrine concentration had changed by 0.01±0.07 nmol/l in liver and by 0.21±0.07 nmol/l in kidney transplant recipients (p<0.05 between groups after 30-40 minutes of water drinking. While blood pressure and systemic vascular resistance increased in both groups, the responses tended to be attenuated in liver transplant recipients. Our findings support the idea that osmosensitive hepatic afferents are involved in water drinking-induced sympathetic activation in human subjects.ClinicalTrials.gov NCT01237431.

  11. Role of afferent input in load-dependent plasticity of rat muscle

    Science.gov (United States)

    Kawano, F.; Umemoto, S.; Higo, Y.; Kawabe, N.; Wang, X. D.; Lan, Y. B.; Ohira, Y.

    We have been studying the role of afferent input in the plasticity of skeletal muscles. The present study was performed to investigate the mechanisms responsible for the deafferentation-related inhibition of the compensatory hypertrophy in rat soleus muscle. Adult male Wistar rats were randomly separated into the control, functionally overloaded (FO), and functionally overloaded + deafferentation (FO+DA) group. The tendons of plantaris and gastrocnemius muscles were transected in the FO rats. The dorsal roots of the spinal cord at the L4-5 segmental levels were additionally transected in the FO+DA rats. The sampling of the soleus was performed 2 weeks after the surgery and ambulation recovery. The single muscle fibers were isolated in low-calcium relaxing solution. Further, the myonuclei or argyrophilic nucleolar organizer regions (AgNORs) were stained. Significant increase of the fiber cross-sectional area (CSA) was seen in the FO, but not in the FO+DA, rats. The myonuclear number in fiber was significantly decreased by FO. Addition of DA to FO further promoted the reduction of myonuclear number. The mean nucleus size and DNA content in single nucleus in all groups were identical. Although a single or double AgNORs were seen in ~90% of myonuclei in the control rats, their distributions were 72 and 76% in the FO and FO+DA rats, respectively (phypertrophy. It was also indicated that intact afferent input plays an essential role in these phenomena.

  12. Chemical afferent vagal axotomy blocks re-intake after partial withdrawal of gastric food contents.

    Science.gov (United States)

    Zafra, María A; Molina, Filomena; Puerto, Amadeo

    2017-12-01

    The aim of this study was to investigate the biological process by which animals regulate meal size. An experimental procedure for its study is to examine food re-intake after partial withdrawal of gastric food contents. The aim of the present experiments was to investigate the role of vagal afferents in food re-intake after perivagal administration of capsaicin, a neurotoxin that specifically damages weakly myelinated or unmyelinated vagal sensory axons. In experiment 1, capsaicin-treated animals initially consumed higher amounts of food in comparison to controls (in first 24 hours) but their excess intake was compensated for in subsequent daily satiation tests. However, capsaicin treatment impaired the common short-term re-intake behavior observed in control rats after partial removal of gastric food nutrients, and the lesioned animals consumed significantly less food than had been withdrawn after completion of the initial meal; moreover, in this deficit condition, no counteraction was observed in subsequent repeated tests. This behavioral disturbance cannot be attributed to an indirect effect of capsaicin on gastric emptying volume, because the stomach contents were similar in both groups (Experiment 2). These findings are discussed in terms of the critical role played by vagal afferents in rapid visceral adjustments related to short-term food intake, as also observed in other gastrointestinal regulatory behaviors that require immediate processing of visceral sensory information.

  13. The urodelean Mauthner cell. Morphology of the afferent synapses to the M-cell of larval Salamandra salamandra

    Energy Technology Data Exchange (ETDEWEB)

    Cioni, C.; De Palma, F.; De Vito, L.; Stefanelli, A. [Rome, Univ. (Italy). Dipt. di Biologia Animale e dell`Uomo

    1997-12-31

    In the present work the fine morphology and the distribution of the afferent synapses to the Mauthner cell of larval Salamandra salamandra are described. The aim of the study is to characterize the synaptic bed in the larvae of this terrestrial salamander in order to compare it with that of larval axolotl and larval anurans. Four main types of afferent endings have been identified: myelinated club endings, round-vesicle end bulbs, flattened-vesicle end bulbs and spiral fibers endings. The M-cell afferent synaptology of larval stages of terrestrial amphibians is quite similar to that previously observed in larval stages of aquatic species. This fact can be related to the fundamental similarities between the larval lifestyles.

  14. Afferent projections from the brainstem to the area hypothalamica dorsalis: a horseradish peroxidase study in the cat.

    Science.gov (United States)

    Aguirre, J A; Coveñas, R; Alonso, J R; Lara, J M; Aijón, J

    1989-06-01

    Experiments using the retrograde transport of horseradish peroxidase were performed in order to identify the cells of origin the ascending projections from different brainstem regions to the area hypothalamica dorsalis (aHd) in the cat. The afferent inputs to this area originate mainly from the midbrain and medulla oblongata regions. The main afferent source of the area hypothalamica dorsalis arises from the substantia grisea centralis, where a large number of labeled cells were observed bilaterally, although more abundant on the ipsilateral side. Substantial afferents reach the aHd from the nuclei vestibularis medialis and inferior and the formatio reticularis mesencephali. A modest number of peroxidase-labeled neurons were observed in the nuclei ruber, interpeduncularis, substantia nigra, reticularis gigantocellularis, vestibularis lateralis, cuneatus and gracilis. From the pons, the nucleus raphe magnus sends a weak projection to the aHd. These anatomical data suggest that such area could be involved in visceral, sexual, nociceptive somatosensorial, sleep-waking and motor mechanisms.

  15. Critical Airway Team: A Retrospective Study of an Airway Response System in a Pediatric Hospital.

    Science.gov (United States)

    Sterrett, Emily C; Myer, Charles M; Oehler, Jennifer; Das, Bobby; Kerrey, Benjamin T

    2017-12-01

    Objective Study the performance of a pediatric critical airway response team. Study Design Case series with chart review. Setting Freestanding academic children's hospital. Subjects and Methods A structured review of the electronic medical record was conducted for all activations of the critical airway team. Characteristics of the activations and patients are reported using descriptive statistics. Activation of the critical airway team occurred 196 times in 46 months (March 2012 to December 2015); complete data were available for 162 activations (83%). For 49 activations (30%), patients had diagnoses associated with difficult intubation; 45 (28%) had a history of difficult laryngoscopy. Results Activation occurred at least 4 times per month on average (vs 3 per month for hospital-wide codes). The most common reasons for team activation were anticipated difficult intubation (45%) or failed intubation attempt (20%). For 79% of activations, the team performed an airway procedure, most commonly direct laryngoscopy and tracheal intubation. Bronchoscopy was performed in 47% of activations. Surgical airway rescue was attempted 4 times. Cardiopulmonary resuscitation occurred in 41 activations (25%). Twenty-nine patients died during or following team activation (18%), including 10 deaths associated with the critical airway event. Conclusion Critical airway team activation occurred at least once per week on average. Direct laryngoscopy, tracheal intubation, and bronchoscopic procedures were performed frequently; surgical airway rescue was rare. Most patients had existing risk factors for difficult intubation. Given our rate of serious morbidity and mortality, primary prevention of critical airway events will be a focus of future efforts.

  16. An unusual ulnar nerve-median nerve communicating branch.

    OpenAIRE

    Hoogbergen, M M; Kauer, J M

    1992-01-01

    Branching of the ulnar nerve distal to the origin of the dorsal cutaneous branch was investigated in 25 hands in one of which an anatomical variation was observed. This finding may be of importance in the evaluation of certain entrapment phenomena of the ulnar nerve or unexplained sensory loss after trauma or surgical intervention in that particular area.

  17. Transient femoral nerve palsy following ilioinguinal nerve block for ...

    African Journals Online (AJOL)

    Nigerian Journal of Surgery ... Background: Elective inguinal hernia repair in young fit patients is preferably done under ilioinguinal nerve block anesthesia in the ambulatory setting to improve ... Conclusion: TFNP is a rare complication of ilioinguinal nerve block which delays patient discharge postambulatory hernioplasty.

  18. Upper airway obstruction in canine laryngeal paralysis.

    Science.gov (United States)

    Amis, T C; Smith, M M; Gaber, C E; Kurpershoek, C

    1986-05-01

    The type and the severity of airway obstruction in 30 dogs with bilateral laryngeal paralysis was assessed, using tidal breathing flow-volume loop (TBFVL) analysis. The dogs had clinical evidence of mild-to-severe upper airway obstruction (ie, respiratory distress, exercise intolerance, stridor). Seventeen dogs had TBFVL consistent with a nonfixed (inspiratory) obstruction, 10 had TBFVL indicative of a fixed (inspiratory/expiratory) obstruction, and 3 had normal TBFVL. Analysis of TBFVL confirmed that dogs with laryngeal paralysis have upper airway obstruction that differs in type and severity. Use of TBFVL provided a quantitative evaluation of airway obstruction and demonstrated the effects of bilateral laryngeal paralysis on the breathing patterns of dogs.

  19. Airway Tree Extraction with Locally Optimal Paths

    DEFF Research Database (Denmark)

    Lo, Pechin Chien Pau; Sporring, Jon; Pedersen, Jesper Johannes Holst

    2009-01-01

    This paper proposes a method to extract the airway tree from CT images by continually extending the tree with locally optimal paths. This is in contrast to commonly used region growing based approaches that only search the space of the immediate neighbors. The result is a much more robust method...... for tree extraction that can overcome local occlusions. The cost function for obtaining the optimal paths takes into account of an airway probability map as well as measures of airway shape and orientation derived from multi-scale Hessian eigen analysis on the airway probability. Significant improvements...... were achieved compared to a region growing based method, with up to 36% longer trees at a slight increase of false positive rate....

  20. Routine airway surveillance in pediatric tracheostomy patients.

    Science.gov (United States)

    Gergin, Ozgul; Adil, Eelam; Kawai, Kosuke; Watters, Karen; Moritz, Ethan; Rahbar, Reza

    2017-06-01

    The aim of this study is to review airway findings in children with tracheostomies who underwent surveillance direct laryngoscopy and bronchoscopy (DLB) to determine the yield of routine airway evaluation in these patients. Retrospective chart review at tertiary referral children's hospital. A retrospective chart review was conducted of all of the children with tracheostomies who underwent DLB after tracheostomy between 1984 and 2015. A total of 303 patients met inclusion criteria. The median time interval between tracheostomy and first follow-up DLB was 12.0 months (IQR 4.8-28.9 months). There was no significant difference in the incidence of airway lesions between patients who underwent endoscopy tracheostomy versus those who had a longer time interval between tracheostomy and DLB (p = 0.16). One hundred sixty seven patients (55.1%) were diagnosed with lesions, with suprastomal granulation (39.9%) being the most common. Symptomatic patients were significantly more likely to have an airway lesion identified (69.9% versus 42.0%; p tracheostomy were significantly more likely to have an airway lesion (p = 0.01). The high incidence of airway lesions noted during surveillance DLB support the utility of routine airway endoscopy in pediatric tracheostomy patients. Symptomatic patients, those with ventilator dependence, or cardiopulmonary or trauma indications for tracheostomy are more likely to have airway lesions and should be monitored closely. The ideal time interval between surveillance endoscopies needs to be examined further. Copyright © 2017. Published by Elsevier B.V.

  1. Impending Airway Compromise due to Cystic Hygroma

    Directory of Open Access Journals (Sweden)

    Itai Shavit

    2011-05-01

    Full Text Available We report on a 3-month-old infant, who arrived in the pediatric emergency department (ED with a cervical cystic hygroma causing an impending compromise of the airway. We recognize that such a lesion can rapidly progress, and the judicious use of imaging in the ED may help to avoid airway compromise and possibly fatal complications. [West J Emerg Med. 2011;12(4:368–369.

  2. Airways obstruction, coal mining, and disability.

    OpenAIRE

    Lapp, N L; Morgan, W K; Zaldivar, G

    1994-01-01

    It has recently been suggested that the inhalation of coal in the absence of complicated coal workers' pneumoconiosis (CWP) or smoking can lead to disabling airways obstruction. The cause of such obstruction has been variously attributed to emphysema or bronchitis. The frequency of significant airways obstruction in a group of United States coal miners seeking compensation for occupationally induced pulmonary impairment was therefore determined. In a sample of 611 "Black Lung" claimants there...

  3. Airway Management in Athletes Wearing Lacrosse Equipment.

    Science.gov (United States)

    Bowman, Thomas G; Boergers, Richard J; Lininger, Monica R

    2018-03-01

      Patient ventilation volume and rate have been found to be compromised due to the inability to seal a pocket mask over the chinstrap of football helmets. The effects of supraglottic airway devices such as the King LT and of lacrosse helmets on these measures have not been studied.   To assess the effects of different airway management devices and helmet conditions on producing quality ventilations while performing cardiopulmonary resuscitation on simulation manikins.   Crossover study.   Simulation laboratory.   Thirty-six athletic trainers (12 men, 24 women) completed this study.   Airway-management device (pocket mask, oral pharyngeal airway, King LT airway [KA]) and helmet condition (no helmet, Cascade helmet, Schutt helmet, Warrior helmet) served as the independent variables. Participant pairs performed 2 minutes of 2-rescuer cardiopulmonary resuscitation under 12 trial conditions.   Ventilation volume (mL), ventilation rate (ventilations/min), rating of perceived difficulty (RPD), and percentage of quality ventilations were the dependent variables.   A significant interaction was found between type of airway-management device and helmet condition on ventilation volume and rate ( F 12,408 = 2.902, P < .0001). In addition, a significant interaction was noted between airway-management device and helmet condition on RPD scores ( F 6,204 = 3.366, P = .003). The no-helmet condition produced a higher percentage of quality ventilations compared with the helmet conditions ( P ≤ .003). Also, the percentage of quality ventilations differed, and the KA outperformed each of the other devices ( P ≤ .029).   The helmet chinstrap inhibited quality ventilation (rate and volume) in airway procedures that required the mask to be sealed on the face. However, the KA allowed quality ventilation in patients wearing a helmet with the chinstrap fastened. If a KA is not available, the helmet may need to be removed to provide quality ventilations.

  4. Ultrasonography as a tool to study afferent feedback from the muscle–tendon complex during human walking

    DEFF Research Database (Denmark)

    Cronin, Neil J.; Klint, Richard Albin Ivar af; Grey, Michael J.

    2011-01-01

    behaviour of afferent receptors, which may in turn affect the motor control. In this review we first summarise research that has incorporated the use of ultrasound-based techniques to study muscle-tendon interaction, predominantly during walking. We then review recent research that has combined this method......In humans, one of the most common tasks in everyday life is walking, and sensory afferent feedback from peripheral receptors, particularly the muscle spindles and Golgi tendon organs (GTO), makes an important contribution to the motor control of this task. One factor that can complicate the ability...

  5. Side Effects: Nerve Problems (Peripheral Neuropathy)

    Science.gov (United States)

    Nerve problems, such as peripheral neuropathy, can be caused by cancer treatment. Learn about signs and symptoms of nerve changes. Find out how to prevent or manage nerve problems during cancer treatment.

  6. Nerve Transfers for Treatment of Isolated Axillary Nerve Injuries.

    Science.gov (United States)

    Wheelock, Margie; Clark, Tod A; Giuffre, Jennifer L

    2015-01-01

    The most common neurological defect in traumatic anterior glenohumeral dislocation is isolated axillary nerve palsy. Most recover spontaneously; however, some have persistent axillary neuropathy. An intact rotator cuff may compensate for an isolated axillary nerve injury; however, given the high rate of rotator cuff pathology with advancing age, patients with an axillary nerve injury are at risk for complete shoulder disability. To review reconstruction of the axillary nerve to alleviate shoulder pain, augment shoulder stability, abduction and external rotation to alleviate sole reliance on the rotator cuff to move and stabilize the shoulder. A retrospective review of 10 patients with an isolated axillary nerve injury and an intact rotator cuff who underwent a triceps nerve branch to axillary nerve transfer was performed. Patient demographics, surgical technique, deltoid strength, donor-site morbidity, complications and time to surgery were evaluated. Ten male patients, mean age 38.3 years (range 18 to 66 years), underwent a triceps to axillary nerve transfer for isolated axillary nerve injury 7.4 months (range five to 12 months) post-traumatic shoulder dislocation. Deltoid function was British Medical Research Council grade 0/5 in all patients preoperatively and ≥3/5 deltoid strength in eight patients at final follow-up (14.8 months [range 12 to 25 months]). There were no complications and no donor-site morbidity. A triceps to axillary nerve transfer for isolated axillary neuropathy following traumatic shoulder dislocation improved shoulder pain, stability and deltoid strength, and potentially preserves shoulder function with advancing age by alleviating sole reliance on the rotator cuff for shoulder abduction and external rotation.

  7. Trichobezoar Causing Airway Compromise during Esophagogastroduodenoscopy

    Directory of Open Access Journals (Sweden)

    Erica Y. Kao

    2015-01-01

    Full Text Available Objectives. (1 Report the case of a 5-year-old female with trichotillomania and trichophagia that suffered airway compromise during esophagogastroduodenoscopy for removal of a trichobezoar. (2 Provide management recommendations for an unusual foreign body causing extubation and partial airway obstruction. Methods. Case report of a rare situation of airway compromise caused by a trichobezoar. Results. A 5-year-old patient underwent endoscopic retrieval of a gastric trichobezoar (hairball by the gastroenterology service under general endotracheal anesthesia in a sedation unit. During removal, the hairball, due to its large size, dislodged the endotracheal tube, effectively extubating the patient. The bezoar became lodged at the cricopharyngeus muscle. Attempts to remove the bezoar or reintubation were unsuccessful. The child was able to be mask ventilated while the otolaryngology service was called. Direct laryngoscopy revealed a hairball partially obstructing the view of the glottis from its position in the postcricoid area. The hairball, still entrapped in the snare from the esophagoscope, was grasped with Magill forceps and slowly extracted. The patient was then reintubated and the airway and esophagus were reevaluated. Conclusions. Trichobezoar is an uncommon cause of airway foreign body. Careful attention to airway management during these and similar foreign body extractions can prevent inadvertent extubations.

  8. Glutamate receptors and the airways hyperreactivity.

    Science.gov (United States)

    Strapkova, Anna; Antosova, Martina

    2012-03-01

    It is proposed the link between the hyperactivity of NMDA receptors and airway hyperresponsiveness. We investigated the effect of agents modulating the activity of NMDA receptors in the ovalbumin-induced airway hyperreactivity in guinea pigs. The airways hyperreactivity was influenced by the agonist (NMDA) and selective antagonist - competitive (AP-5) and non-competitive (MK-801) of NMDA receptors. Airway responsiveness to histamine or acetylcholine was evaluated in in vitro conditions. NMDA administration caused the increase of tracheal smooth muscle response in ovalbumin-induced hyperreactivity to acetylcholine. MK 801 as well as AP-5 provoked the decrease of reactivity mainly to acetylcholine in tracheal smooth muscle, while the former, non-competitive antagonist was more effective. We recorded more pronounced response in tracheal than in lung tissue smooth muscle with more considerable response to acetylcholine than to histamine. The results of experiments show the modification of airway smooth muscles responses by agents modulating the activity of NMDA receptors. They confirm the possibility of NMDA receptors participation in experimental airway hyperreactivity. The results enlarge information regarding the link of the inflammatory diseases and glutamatergic system.

  9. Link between vitamin D and airway remodeling

    Directory of Open Access Journals (Sweden)

    Berraies A

    2014-04-01

    Full Text Available Anissa Berraies, Kamel Hamzaoui, Agnes HamzaouiPediatric Respiratory Diseases Department, Abderrahmen Mami Hospital, Ariana, and Research Unit 12SP15 Tunis El Manar University, Tunis, TunisiaAbstract: In the last decade, many epidemiologic studies have investigated the link between vitamin D deficiency and asthma. Most studies have shown that vitamin D deficiency increases the risk of asthma and allergies. Low levels of vitamin D have been associated with asthma severity and loss of control, together with recurrent exacerbations. Remodeling is an early event in asthma described as a consequence of production of mediators and growth factors by inflammatory and resident bronchial cells. Consequently, lung function is altered, with a decrease in forced expiratory volume in one second and exacerbated airway hyperresponsiveness. Subepithelial fibrosis and airway smooth muscle cell hypertrophy are typical features of structural changes in the airways. In animal models, vitamin D deficiency enhances inflammation and bronchial anomalies. In severe asthma of childhood, major remodeling is observed in patients with low vitamin D levels. Conversely, the antifibrotic and antiproliferative effects of vitamin D in smooth muscle cells have been described in several experiments. In this review, we briefly summarize the current knowledge regarding the relationship between vitamin D and asthma, and focus on its effect on airway remodeling and its potential therapeutic impact for asthma.Keywords: vitamin D, asthma, airway remodeling, airway smooth muscle, supplementation

  10. Ultrasound: A novel tool for airway imaging

    Directory of Open Access Journals (Sweden)

    Siddharthkumar Bhikhabhai Parmar

    2014-01-01

    Full Text Available Context: The scope of ultrasound is emerging in medical science, particularly outside traditional areas of radiology practice. Aims: We designed this study to evaluate feasibility of bedside sonography as a tool for airway assessment and to describe sonographic anatomy of airway. Settings and Design: A prospective, clinical study. Materials and Methods: We included 100 adult, healthy volunteers of either sex to undergo airway imaging systemically starting from floor of the mouth to the sternal notch in anterior aspect of neck by sonography. Results: We could visualize mandible and hyoid bone as a bright hyperechoic structure with hypoechoic acoustic shadow underneath. Epiglottis, thyroid cartilage, cricoid cartilage, and tracheal rings appeared hypoechoic. Vocal cords were visualized through thyroid cartilage. Interface between air and mucosa lining the airway produced a bright hyperechoic linear appearance. Artifacts created by intraluminal air prevented visualization of posterior pharynx, posterior commissure, and posterior wall of trachea. Conclusions: Ultrasound is safe, quick, noninvasive, repeatable, and bedside tool to assess the airway and can provide real-time dynamic images relevant for several aspects of airway management.

  11. Histological modifications of the rat prostate following transection of somatic and autonomic nerves

    Directory of Open Access Journals (Sweden)

    Rosaura Diaz

    2010-06-01

    Full Text Available It is known that hormones influence significantly the prostate tissue. However, we reported that mating induces an increase in androgen receptors, revealing a neural influence on the gland. These data suggested that somatic afferents (scrotal and genitofemoral nerves and autonomic efferents (pelvic and hypogastric nerves could regulate the structure of the prostate. Here we assessed the role of these nerves in maintaining the histology of the gland. Hence, afferent or efferent nerves of male rats were transected. Then, the ventral and dorsolateral regions of the prostate were processed for histology. Results showed that afferent transection affects prostate histology. The alveoli area decreased and increased in the ventral and dorsolateral prostate, respectively. The epithelial cell height increased in both regions. Efferent denervation produced dramatic changes in the prostate gland. The tissue lost its configuration, and the epithelium became scattered and almost vanished. Thus, afferent nerves are responsible for spinal processes pertaining to the trophic control of the prostate, activating its autonomic innervation. Hence, our data imply that innervation seems to be synergic with hormones for the healthy maintenance of the prostate. Thus, it is suggested that some prostate pathologies could be due to the failure of the autonomic neural pathways regulating the gland.Sabe-se que os hormônios influenciam significativamente o tecido prostático. Entretanto, nós demonstramos que o acasalamento induz um aumento nos receptores androgênicos, revelando uma influência neural sobre a glândula. Esses dados sugerem que os aferentes somáticos (nervos escrotal e genito-femural e os eferentes autonômicos (nervos pélvicos e hipo-gástricos poderiam regular a estrutura da próstata. Neste trabalho, avaliou-se a função destes nervos na manutenção da histologia da glândula. Dessa forma, os nervos aferentes e eferentes de ratos machos foram

  12. Inhibition of pan neurotrophin receptor p75 attenuates diesel particulate-induced enhancement of allergic airway responses in C57/B16J mice.

    Science.gov (United States)

    Farraj, Aimen K; Haykal-Coates, Najwa; Ledbetter, Allen D; Evansky, Paul A; Gavett, Stephen H

    2006-06-01

    Recent investigations have linked neurotrophins, including nerve growth factor (NGF), neurotrophin-3 (NT-3), and brain-derived neurotrophic factor (BDNF), to allergic airways diseases. Antibody blockade of NGF attenuates airway resistance in allergic mice. Diesel exhaust particle (DEP) exposure has been linked to asthma exacerbation in many cities with vehicular traffic congestion. We tested the hypothesis that DEP-induced enhancement of the hallmark features of allergic airway disease in a murine model is dependent on the function of the pan neurotrophin receptor p75. Ovalbumin (OVA)-sensitized C57B1/6J mice were intranasally instilled with an antibody against the p75 receptor or saline alone 1 h before OVA challenge. The mice were then exposed nose-only to the PM2.5 fraction of SRM2975 DEP or air alone for 5 h beginning 1 h after OVA challenge. Two days later, air-exposed OVA-allergic mice developed a small but insignificant increase in methacholine-induced airflow obstruction relative to air-exposed, vehicle-sensitized mice. DEP-exposed OVA-allergic mice had a significantly greater degree of airway obstruction than all other groups. Instillation of anti-p75 significantly attenuated the DEP-induced increase in airway obstruction in OVA-allergic mice to levels similar to non-sensitized mice. The DEP-induced exacerbation of allergic airway responses may, in part, be mediated by neurotrophins.

  13. Airway foreign body in children

    Directory of Open Access Journals (Sweden)

    Marina GONZÁLEZ-HERRERO

    2018-03-01

    Full Text Available Introduction and objective: The aspiration of a foreign body in children is a frequent emergency in pediatrics, being potentially lethal. Method: Narrative review. Results: This pathology mainly affects children under 5 years of age with a peak of incidence between the first and third years of life. The clinic will depend on the type of foreign body (size, shape, possibility of breaking, organic or not, the age of the child and the location of the object. In our environment, the most frequent is the aspiration of nuts (peanuts and sunflower seeds. After the initial picture, an asymptomatic period tends to occur, which favors delayed diagnosis and leads to possible errors in the diagnosis. Discussion: An adequate clinical history and a high diagnostic suspicion are fundamental to favor an early treatment. The presence of a normal chest X-ray does not exclude the presence of a foreign body in the airway, so a bronchoscopy is indicated if the diagnostic suspicion is high. The treatment of choice is extraction by rigid bronchoscopy, being controversial the use of flexible fibrobronchoscope. Conclusions: Conclusions: The aspiration of a foreign body is a pediatric emergency that requires a diagnosis and early treatment. The highest incidence occurs in children under 3 years and more frequently in men. The most commonly aspirated material in our environment are nuts, mainly located in the bronchial tree. The initial episode may go unnoticed, delaying the diagnosis and may lead to progressive respiratory distress in the child. A detailed clinical history and suspicion of this pathology are essential in children at risk age who present with cough and dyspnea of sudden onset. The existence of a normal chest radiograph should not postpone bronchoscopy when there is high clinical suspicion. The treatment of choice for the extraction of foreign bodies in airways in children is rigid bronchoscopy, being controversial the use of the flexible fibrobronchoscope

  14. The Surgical Management of Facial Nerve Injury

    OpenAIRE

    Rovak, Jason M.; Tung, Thomas H.; Mackinnon, Susan E.

    2004-01-01

    The surgical management of facial nerve injuries is dependent upon a thorough understanding of facial nerve anatomy, nerve physiology, and microsurgical techniques. When possible, primary neurorrhaphy is the “gold standard” repair technique. Injuries resulting in long nerve gaps or a significant delay between the time of injury and repair requires alterative techniques, such as nerve grafts, nerve transfers, regional muscle transfers, free tissue transfers, and static procedures. Scrupulous t...

  15. Neuromas of the calcaneal nerves.

    Science.gov (United States)

    Kim, J; Dellon, A L

    2001-11-01

    A neuroma of a calcaneal nerve has never been reported. A series of 15 patients with heel pain due to a neuroma of a calcaneal nerve are reviewed. These patients previously had either a plantar fasciotomy (n = 4), calcaneal spur removal (n = 2), ankle fusion (n = 2), or tarsal tunnel decompression (n = 7). Neuromas occurred on calcaneal branches that arose from either the posterior tibial nerve (n = 1), lateral plantar nerve (n = 1), the medial plantar nerve (n = 9), or more than one of these nerves (n = 4). Operative approach was through an extended tarsal tunnel incision to permit identification of all calcaneal nerves. The neuroma was resected and implanted into the flexor hallucis longus muscle. Excellent relief of pain occurred in 60%, and good relief in 33%. One patient (17%) had no improvement and required resection of the lateral plantar nerve. Awareness that the heel may be innervated by multiple calcaneal branches suggests that surgery for heel pain of neural origin employ a surgical approach that permits identification of all possible calcaneal branches.

  16. Diagnostic nerve ultrasonography; Diagnostische Nervensonographie

    Energy Technology Data Exchange (ETDEWEB)

    Baeumer, T. [Universitaet zu Luebeck CBBM, Haus 66, Institut fuer Neurogenetik, Luebeck (Germany); Grimm, A. [Universitaetsklinikum Tuebingen, Klinik und Poliklinik fuer Neurologie, Tuebingen (Germany); Schelle, T. [Staedtisches Klinikum Dessau, Neurologische Klinik, Dessau (Germany)

    2017-03-15

    For the diagnostics of nerve lesions an imaging method is necessary to visualize peripheral nerves and their surrounding structures for an etiological classification. Clinical neurological and electrophysiological investigations provide functional information about nerve lesions. The information provided by a standard magnetic resonance imaging (MRI) examination is inadequate for peripheral nerve diagnostics; however, MRI neurography is suitable but on the other hand a resource and time-consuming method. Using ultrasonography for peripheral nerve diagnostics. With ultrasonography reliable diagnostics of entrapment neuropathies and traumatic nerve lesions are possible. The use of ultrasonography for neuropathies shows that a differentiation between different forms is possible. Nerve ultrasonography is an established diagnostic tool. In addition to the clinical examination and clinical electrophysiology, structural information can be obtained, which results in a clear improvement in the diagnostics. Ultrasonography has become an integral part of the diagnostic work-up of peripheral nerve lesions in neurophysiological departments. Nerve ultrasonography is recommended for the diagnostic work-up of peripheral nerve lesions in addition to clinical and electrophysiological investigations. It should be used in the clinical work-up of entrapment neuropathies, traumatic nerve lesions and spacy-occupying lesions of nerves. (orig.) [German] Fuer die Diagnostik von Nervenlaesionen ist ein bildgebendes Verfahren zur Darstellung des peripheren Nervs und seiner ihn umgebenden Strukturen fuer eine aetiologische Einordnung erforderlich. Mit der klinisch-neurologischen Untersuchung und Elektrophysiologie ist eine funktionelle Aussage ueber die Nervenlaesion moeglich. In der Standard-MRT-Untersuchung wird der periphere Nerv nur unzureichend gut dargestellt. Die MRT-Neurographie ist ein sehr gutes, aber auch zeit- und ressourcenintensives Verfahren. Nutzung des Ultraschalls fuer die

  17. DC-Evoked Modulation of Excitability of Myelinated Nerve Fibers and Their Terminal Branches; Differences in Sustained Effects of DC.

    Science.gov (United States)

    Kaczmarek, Dominik; Jankowska, Elzbieta

    2018-03-15

    Direct current (DC) evokes long-lasting changes in neuronal networks both presynaptically and postsynaptically and different mechanisms were proposed to be involved in them. Different mechanisms were also suggested to account for the different dynamics of presynaptic DC actions on myelinated nerve fibers stimulated before they entered the spinal gray matter and on their terminal branches. The aim of the present study was to examine whether these different dynamics might be related to differences in the involvement of K + channels. To this end, we compared effects of the K + channel blocker 4-amino-pyridine (4-AP) on DC-evoked changes in the excitability of afferent fibers stimulated within the dorsal columns (epidurally) and within their projection areas in the dorsal horn and motor nuclei (intraspinally). 4-AP was applied systemically in deeply anesthetized rats. DC-evoked increases in the excitability of epidurally stimulated afferent nerve fibers, and increases in field potentials evoked by these fibers, were not affected by 4-AP. In contrast, sustained decreases rather than increases in the excitability of intraspinally stimulated terminal nerve branches were evoked by local application of DC in conjunction with 4-AP. The study leads to the conclusion that 4-AP-sensitive K + channels contribute to the sustained DC-evoked post-polarization increases in the excitability at the level of terminal branches of nerve fibers but not of the nodes of Ranvier nor within the juxta-paranodal regions where other mechanisms would be involved in inducing the sustained DC-evoked changes. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

  18. BOLD fMRI deactivation of limbic and temporal brain structures and mood enhancing effect by transcutaneous vagus nerve stimulation.

    Science.gov (United States)

    Kraus, T; Hösl, K; Kiess, O; Schanze, A; Kornhuber, J; Forster, C

    2007-01-01

    Direct vagus nerve stimulation (VNS) has proved to be an effective treatment for seizure disorder and major depression. However, since this invasive technique implies surgery, with its side-effects and relatively high financial costs, a non-invasive method to stimulate vagal afferences would be a great step forward. We studied effects of non-invasive electrical stimulation of the nerves in the left outer auditory canal in healthy subjects (n = 22), aiming to activate vagal afferences transcutaneously (t-VNS). Short-term changes in brain activation and subjective well-being induced by t-VNS were investigated by functional magnetic resonance imaging (fMRI) and psychometric assessment using the Adjective Mood Scale (AMS), a self-rating scale for current subjective feeling. Stimulation of the ear lobe served as a sham control. fMRI showed that robust t-VNS induced BOLD-signal decreases in limbic brain areas, including the amygdala, hippocampus, parahippocampal gyrus and the middle and superior temporal gyrus. Increased activation was seen in the insula, precentral gyrus and the thalamus. Psychometric assessment revealed significant improvement of well-being after t-VNS. Ear lobe stimulation as a sham control intervention did not show similar effects in either fMRI or psychometric assessment. No significant effects on heart rate, blood pressure or peripheral microcirculation could be detected during the stimulation procedure. Our study shows the feasibility and beneficial effects of transcutaneous nerve stimulation in the left auditory canal of healthy subjects. Brain activation patterns clearly share features with changes observed during invasive vagus nerve stimulation.

  19. Postsynaptic P2X3-containing receptors in gustatory nerve fibres mediate responses to all taste qualities in mice.

    Science.gov (United States)

    Vandenbeuch, Aurelie; Larson, Eric D; Anderson, Catherine B; Smith, Steven A; Ford, Anthony P; Finger, Thomas E; Kinnamon, Sue C

    2015-03-01

    Taste buds release ATP to activate ionotropic purinoceptors composed of P2X2 and P2X3 subunits, present on the taste nerves. Mice with genetic deletion of P2X2 and P2X3 receptors (double knockout mice) lack responses to all taste stimuli presumably due to the absence of ATP-gated receptors on the afferent nerves. Recent experiments on the double knockout mice showed, however, that their taste buds fail to release ATP, suggesting the possibility of pleiotropic deficits in these global knockouts. To test further the role of postsynaptic P2X receptors in afferent signalling, we used AF-353, a selective antagonist of P2X3-containing receptors to inhibit the receptors acutely during taste nerve recording and behaviour. The specificity of AF-353 for P2X3-containing receptors was tested by recording Ca(2+) transients to exogenously applied ATP in fura-2 loaded isolated geniculate ganglion neurons from wild-type and P2X3 knockout mice. ATP responses were completely inhibited by 10 μm or 100 μm AF-353, but neither concentration blocked responses in P2X3 single knockout mice wherein the ganglion cells express only P2X2-containing receptors. Furthermore, AF-353 had no effect on taste-evoked ATP release from taste buds. In wild-type mice, i.p. injection of AF-353 or simple application of the drug directly to the tongue, inhibited taste nerve responses to all taste qualities in a dose-dependent fashion. A brief access behavioural assay confirmed the electrophysiological results and showed that preference for a synthetic sweetener, SC-45647, was abolished following i.p. injection of AF-353. These data indicate that activation of P2X3-containing receptors is required for transmission of all taste qualities. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

  20. The Vagus Nerve in the Neuro-Immune Axis: Implications in the Pathology of the Gastrointestinal Tract

    Directory of Open Access Journals (Sweden)

    Bruno Bonaz

    2017-11-01

    Full Text Available The vagus nerve (VN is the longest nerve of the organism and a major component of the parasympathetic nervous system which constitutes the autonomic nervous system (ANS, with the sympathetic nervous system. There is classically an equilibrium between the sympathetic and parasympathetic nervous systems which is responsible for the maintenance of homeostasis. An imbalance of the ANS is observed in various pathologic conditions. The VN, a mixed nerve with 4/5 afferent and 1/5 efferent fibers, is a key component of the neuro-immune and brain-gut axes through a bidirectional communication between the brain and the gastrointestinal (GI tract. A dual anti-inflammatory role of the VN is observed using either vagal afferents, targeting the hypothalamic–pituitary–adrenal axis, or vagal efferents, targeting the cholinergic anti-inflammatory pathway. The sympathetic nervous system and the VN act in synergy, through the splenic nerve, to inhibit the release of tumor necrosis factor-alpha (TNFα by macrophages of the peripheral tissues and the spleen. Because of its anti-inflammatory effect, the VN is a therapeutic target in the treatment of chronic inflammatory disorders where TNFα is a key component. In this review, we will focus on the anti-inflammatory role of the VN in inflammatory bowel diseases (IBD. The anti-inflammatory properties of the VN could be targeted pharmacologically, with enteral nutrition, by VN stimulation (VNS, with complementary medicines or by physical exercise. VNS is one of the alternative treatments for drug resistant epilepsy and depression and one might think that VNS could be used as a non-drug therapy to treat inflammatory disorders of the GI tract, such as IBD, irritable bowel syndrome, and postoperative ileus, which are all characterized by a blunted autonomic balance with a decreased vagal tone.

  1. Mechanical interactions between adjacent airways in the lung.

    Science.gov (United States)

    Ma, Baoshun; Bates, Jason H T

    2014-03-15

    The forces of mechanical interdependence between the airways and the parenchyma in the lung are powerful modulators of airways responsiveness. Little is known, however, about the extent to which adjacent airways affect each other's ability to narrow due to distortional forces generated within the intervening parenchyma. We developed a two-dimensional computational model of two airways embedded in parenchyma. The parenchyma itself was modeled in three ways: 1) as a network of hexagonally arranged springs, 2) as a network of triangularly arranged springs, and 3) as an elastic continuum. In all cases, we determined how the narrowing of one airway was affected when the other airway was relaxed vs. when it narrowed to the same extent as the first airway. For the continuum and triangular network models, interactions between airways were negligible unless the airways lay within about two relaxed diameters of each other, but even at this distance the interactions were small. By contrast, the hexagonal spring network model predicted that airway-airway interactions mediated by the parenchyma can be substantial for any degree of airway separation at intermediate values of airway contraction forces. Evidence to date suggests that the parenchyma may be better represented by the continuum model, which suggests that the parenchyma does not mediate significant interactions between narrowing airways.

  2. SIMPLE, TIMELY, SAFELY? LARYNGEAL MASK AND PEDIATRIC AIRWAY.

    Science.gov (United States)

    Karišik, Marijana

    2016-03-01

    Laryngeal mask airway (LMA) was a useful, powerful airway management device for routine pediatric airway management, pediatric difficult airway, and in pediatric emergency situations. Over years, various designs, induction and insertion techniques have been described. LMA provides ease of placement and removal as compared with endotracheal intubation, less traumatism for the respiratory tract, better tolerability by patients, improved hemodynamic stability during emergency, less coughing, less sore throat, avoidance of laryngoscopy, and hands free airway. On the other hand, LMA is not suitable to overcome functional airway problems and mechanical airway obstruction in children. Simple airway management in pediatric patients is normally easy in experienced hands, for anesthesiologists working in specialized hospitals with appropriate personnel and equipment that guarantee optimal safety in these patients. On the other hand, pediatric airway management is a great challenge for anesthesiologists working in departments with a small number of pediatric surgical procedures. Careful preoperative evaluation, preparation and training in the recognition of challenges in pediatric airway are essential for the management of the airway in children. LMA plays a special role in the management of difficult pediatric airway; as a supraglottic airway device, it is incorporated into difficult pediatric airway algorithms.

  3. Bioenergetics and ATP Synthesis during Exercise: Role of Group III/IV Muscle Afferents.

    Science.gov (United States)

    Broxterman, Ryan M; Layec, Gwenael; Hureau, Thomas J; Morgan, David E; Bledsoe, Amber D; Jessop, Jacob E; Amann, Markus; Richardson, Russell S

    2017-12-01

    The purpose of this study was to investigate the role of the group III/IV muscle afferents in the bioenergetics of exercising skeletal muscle beyond constraining the magnitude of metabolic perturbation. Eight healthy men performed intermittent isometric knee-extensor exercise to task failure at ~58% maximal voluntary contraction under control conditions (CTRL) and with lumbar intrathecal fentanyl to attenuate group III/IV leg muscle afferents (FENT). Intramuscular concentrations of phosphocreatine (PCr), inorganic phosphate (Pi), diprotonated phosphate (H2PO4), adenosine triphosphate (ATP), and pH were determined using phosphorous magnetic resonance spectroscopy (P-MRS). The magnitude of metabolic perturbation was significantly greater in FENT compared with CTRL for [Pi] (37.8 ± 16.8 vs 28.6 ± 8.6 mM), [H2PO4] (24.3 ± 12.2 vs 17.9 ± 7.1 mM), and [ATP] (75.8% ± 17.5% vs 81.9% ± 15.8% of baseline), whereas there was no significant difference in [PCr] (4.5 ± 2.4 vs 4.4 ± 2.3 mM) or pH (6.51 ± 0.10 vs 6.54 ± 0.14). The rate of perturbation in [PCr], [Pi], [H2PO4], and pH was significantly faster in FENT compared with CTRL. Oxidative ATP synthesis was not significantly different between conditions. However, anaerobic ATP synthesis, through augmented creatine kinase and glycolysis reactions, was significantly greater in FENT than in CTRL, resulting in a significantly greater ATP cost of contraction (0.049 ± 0.016 vs 0.038 ± 0.010 mM·min·N). Group III/IV muscle afferents not only constrain the magnitude of perturbation in intramuscular Pi, H2PO4, and ATP during small muscle mass exercise but also seem to play a role in maintaining efficient skeletal muscle contractile function in men.

  4. Continuous positive airway pressure (CPAP).

    Science.gov (United States)

    Sahni, R; Wung, J T

    1998-01-01

    Progress in neonatal intensive care is closely linked to improvements in the management of respiratory failure in small infants. This applies to the care of the preterm infants with immature lungs, and also to treatment of the preterm or full term infants with specific diseases that are associated with respiratory failure. Respiratory distress of the newborn continues to account for significant morbidity in the intensive care unit. The spectrum of disease ranges from mild distress to severe respiratory failure requiring varying degrees of support. The current modalities of ventilatory assistance range from the more benign continuous positive airway pressure (CPAP) to conventional mechanical ventilation, and on to high frequency ventilation. It is a reasonable supposition that the type of ventilatory assistance provided to these infants should be graded according to the severity of the disease. However, the principal objective in selecting the mode of respiratory support should be to use a modality which results in minimal volo- or barotrauma to the infant. The following detailed description on CPAP explains its physiological effects, delivery system, indications for use, application, maintenance, and associated complications. The equipment described is simple to use, has a greater cost benefit, and has a more universal application, which is of help to smaller units including those in the developing parts of the world. We have also included our institutional clinical experience of CPAP usage in very low birth weight infants from the periods before and after commercial availability of surfactant in the United States.

  5. Lower airway papillomatosis in children.

    Science.gov (United States)

    Zawadzka-Głos, Lidia; Jakubowska, Anna; Chmielik, Mieczysław; Bielicka, Anna; Brzewski, Michał

    2003-10-01

    Laryngeal papilloma in children is a frequent disease caused by human papilloma virus (HPV) type 6 or type 11. This disease has a tendency to recur and the changes are histologically benign. In some cases papilloma may affect the lower levels of the respiratory tract. In this study, among 90 patients treated for laryngeal papillomatosis, in four children papilloma of trachea, bronchi and lung tissue were detected in endoscopic and radiological examination. This constitutes 4.4% of all patients. Compact nodules and acquired cysts between 5 and 50 mm long were found in chest X-rays and in computerised tomography. These cysts appeared from 4 to 8 years after establishing a diagnosis of laryngeal papilloma, and 1 year after recognising papilloma in the trachea. In all four children the presence of nodules and cysts in the lungs was preceded by recurrent pneumonia, emphysema or atelectasis of the lungs. All children with laryngeal papillomatosis should have a chest X-ray. Detection of acquired cyst-like changes in lung tissue in children with laryngeal papillomatosis is a warning of future papilloma in the trachea and bronchi, with involvement of lung tissue. In differential diagnosis of these changes in the lungs we should take into consideration the presence of papilloma in the bronchi. A prognosis of papillomatosis in the lower airways in children is always serious.

  6. Automatic airway-artery analysis on lung CT to quantify airway wall thickening and bronchiectasis

    DEFF Research Database (Denmark)

    Perez-Rovira, Adria; Kuo, Wieying; Petersen, Jens

    2016-01-01

    Purpose: Bronchiectasis and airway wall thickening are commonly assessed in computed tomography (CT) by comparing the airway size with the size of the accompanying artery. Thus, in order to automate the quantification of bronchiectasis and wall thickening following a similar principle, there is a...

  7. Extracellular matrix in airway smooth muscle is associated with dynamics of airway function in asthma

    NARCIS (Netherlands)

    Yick, C. Y.; Ferreira, D. S.; Annoni, R.; von der Thüsen, J. H.; Kunst, P. W.; Bel, E. H.; Lutter, R.; Mauad, T.; Sterk, P. J.

    2012-01-01

    Background: Altered deposition of extracellular matrix (ECM) in the airway smooth muscle (ASM) layer as observed in asthma may influence ASM mechanical properties. We hypothesized that ECM in ASM is associated with airway function in asthma. First, we investigated the difference in ECM expression in

  8. Fine structure of primary afferent axon terminals projecting from rapidly adapting mechanoreceptors of the toe and foot pads of the cat.

    Science.gov (United States)

    Maxwell, D J; Bannatyne, B A; Fyffe, R E; Brown, A G

    1984-04-01

    Two Pacinian corpuscle afferents and two rapidly adapting afferents from Krause corpuscles were intra-axonally labelled with horseradish peroxidase in the lumbosacral enlargement of the cat's spinal cord. Tissue was prepared for combined light and electron microscopical analysis. Boutons from both classes of afferent had similar ultrastructural appearances. They both formed from one to three synaptic junctions with dendritic shafts and spines and received axo-axonic synapses. In addition, both categories of bouton were seen to be presynaptic to structures interpreted as vesicle-containing dendrites. It is concluded that both types of afferent fibre are subject to presynaptic control and that they synapse with dorsal horn neurones which are possibly interneurones involved in primary afferent depolarization and post-synaptic dorsal column neurones.

  9. Vagus Nerve Stimulation.

    Science.gov (United States)

    Ekmekçi, Hakan; Kaptan, Hülagu

    2017-06-15

    The vagus nerve stimulation (VNS) is an approach mainly used in cases of intractable epilepsy despite all the efforts. Also, its benefits have been shown in severe cases of depression resistant to typical treatment. The aim of this study was to present current knowledge of vagus nerve stimulation. A new value has emerged just at this stage: VNS aiming the ideal treatment with new hopes. It is based on the placement of a programmable generator on the chest wall. Electric signals from the generator are transmitted to the left vagus nerve through the connection cable. Control on the cerebral bioelectrical activity can be achieved by way of these signal sent from there in an effort for controlling the epileptic discharges. The rate of satisfactory and permanent treatment in epilepsy with monotherapy is around 50%. This rate will increase by one-quarters (25%) with polytherapy. However, there is a patient group roughly constituting one-thirds of this population, and this group remains unresponsive or refractory to all the therapies and combined regimes. The more the number of drugs used, the more chaos and side effects are observed. The anti-epileptic drugs (AEDs) used will have side effects on both the brain and the systemic organs. Cerebral resection surgery can be required in some patients. The most commonly encountered epilepsy type is the partial one, and the possibility of benefiting from invasive procedures is limited in most patients of this type. Selective amygdala-hippocampus surgery is a rising value in complex partial seizures. Therefore, as epilepsy surgery can be performed in very limited numbers and rather developed centres, success can also be achieved in limited numbers of patients. The common ground for all the surgical procedures is the target of preservation of memory, learning, speaking, temper and executive functions as well as obtaining a good control on seizures. However, the action mechanism of VNS is still not exactly known. On the other hand

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

    Directory of Open Access Journals (Sweden)

    EMANUELA eVARALDO

    2014-07-01

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

  11. Bronchial thermoplasty and the role of airway smooth muscle: are we on the right direction?

    Science.gov (United States)

    Menzella, Francesco; Lusuardi, Mirco; Galeone, Carla; Facciolongo, Nicola

    2017-01-01

    Asthma is characterized by inflammation of the airways that includes eosinophils, basal membrane thickening, epithelial sloughing, vascular changes, smooth muscle hypertrophy and hyperplasia, and mucous gland hyperplasia. Recently, there have been studies on the role of hypersensitivity and inflammation in asthma, but the role of bronchial smooth muscle remains unclear. Bronchial thermoplasty is an endoscopic procedure that is approved by the US Food and Drug Administration (FDA) for the treatment of severe refractory asthma, based on the local delivery of radio frequency at 65°C to the airways, with the aim of controlling bronchospasm through a reduction of airway smooth muscle (ASM). Several recent studies have shown significant improvement in clinical outcomes of bronchial thermoplasty for asthma, including symptom control, reduction in exacerbation and hospitalization rates, improved quality of life, and reduction in number of working days or school days lost due to asthma. Data from these recent studies have shown reduction in ASM following bronchial thermoplasty and changes in inflammation patterns. It has also been argued that bronchial thermoplasty may have modulating effects on neuroendocrine epithelial cells, bronchial nerve endings, TRPV1 nerve receptors, and type-C unmyelinated fibers in the bronchial mucosa. This may involve interrupting the central and local reflexes responsible for the activation of bronchospasm in the presence of bronchial hyperreactivity. Several questions remain regarding the use of bronchial thermoplasty, mechanism of action, selection of appropriate patients, and long-term effects. In this review, the role of ASM in the pathogenesis of asthma and the key aspects of bronchial thermoplasty are discussed, with a focus on the potential clinical effects of this promising procedure, beyond the reduction in ASM.

  12. Laryngotracheal anomalies and airway fluoroscopy in infants.

    Science.gov (United States)

    Isaiah, Amal; Pereira, Kevin D

    2017-06-01

    The role of airway fluoroscopy in the diagnosis of laryngotracheal anomalies in infants is controversial. We aimed to (i) compare airway fluoroscopic characteristics with endoscopic findings in infants presenting for evaluation of upper airway obstruction and (ii) assess the as low as is reasonably achievable (ALARA) status for airway fluoroscopy as an initial diagnostic test in suspected laryngotracheal anomalies. We performed a retrospective review of children who underwent fluoroscopy and endoscopic evaluation of the airway in the operating room for suspected laryngotracheal anatomic abnormalities. Thirty-four infants who underwent both procedures at a tertiary level university-based children's hospital from January 1, 2008 to December 1, 2013 were included. Infants with suspected foreign bodies or an existing tracheostomy were excluded. Intraoperative findings from endoscopy and radiologic interpretation from fluoroscopy were compared using standard tools for validation of a diagnostic test. These metrics were compared with historic data that suggested good correlation between radiologic and endoscopic findings in older children. The median age was 3.6 months (range 1-8 months). The sensitivity of airway fluoroscopy for determining laryngotracheal pathology was 18%. Specificity, positive predictive value and negative predictive value were 83%, 67% and 35%, respectively. Although each fluoroscopic exposure was optimized for pediatric patients, the median cumulative exposure to ionizing radiation was 19 mR (range 10-34 mR). Airway fluoroscopy yields metrics that are overall poor to be considered a valid and accurate universal radiologic diagnostic test in infants evaluated for laryngotracheal pathology. The cumulative exposure to ionizing radiation from use of a fluoroscope cannot be justified by the sensitivity of the test and may not conform to ALARA standards for imaging in this population. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. [Suprascapular nerve entrapment syndrome].

    Science.gov (United States)

    Lang, C; Druschky, K F; Sturm, U; Neundörfer, B; Fahlbusch, R

    1988-09-02

    Nineteen patients with isolated suprascapular entrapment neuropathy were seen between 1980 and 1986. A neurogenic cause and absence of other deficits were confirmed by electromyography. Electroneurographic tests were performed in 13 and demonstrated delayed conduction time and (or) reduction in stimulus response amplitude. In 16 patients there was an acute or chronic mechanical cause (direct pressure on the suprascapular nerve, forced dislocation of the shoulder blade). Two types of paralysis could be distinguished, an upper one affecting both the infra- and the supraspinatus muscles (12 patients), and a lower one involving only the infraspinatus muscle (4 patients). In two patients an inflammatory cause was considered likely, while in one the cause remained unclear. Restricting movement brought about an improvement in most patients, while in one the neurophysiological parameters improved after neurosurgical intervention, without complete clinical restoration.

  14. Vagal afferent control of abdominal expiratory activity in response to hypoxia and hypercapnia in rats.

    Science.gov (United States)

    Lemes, Eduardo V; Zoccal, Daniel B

    2014-11-01

    In the present study, we tested the hypothesis that vagal afferent information modulates the pattern of expiratory response to hypercapnia and hypoxia. Simultaneous recordings of airflow, diaphragmatic (DIA) and oblique abdominal muscle (ABD) activities were performed in anesthetized (urethane, 1.2g/kg), tracheostomized, spontaneously breathing male Wistar rats (290-320g, n=12). The animals were exposed to hypercapnia (7 and 10% CO2 for 5min) and hypoxia (7% O2 for 1min) before and after bilateral vagotomy. We verified that the percentage increase in DIA burst amplitude elicited by hypercapnia and hypoxia episodes was similar between intact and vagotomized rats (P>0.05). In contrast, hypercapnia and hypoxia promoted a marked increase in ABD activity in vagotomized, but not in intact rats (Phypoxia in rats. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Thyroid hormone is required for the pruning of afferent type II spiral ganglion neurons in the mouse cochlea

    Science.gov (United States)

    Sundaresan, Srividya; Balasubbu, Suganthalakshmi; Mustapha, Mirna

    2015-01-01

    Afferent connections to the sensory inner and outer hair cells in the cochlea refine and functionally mature during the thyroid hormone (TH)- critical period of inner ear development that occurs perinatally in rodents. In this study, we investigated the effects of hypothyroidism on afferent type II innervation to outer hair cells (OHCs) using the Snell dwarf mouse (Pit1dw). Using a transgenic approach to specifically label type II spiral ganglion neurons, we found that a lack of TH causes persistence of excess type II SGN connections to the OHCs, as well as continued expression of the hair cell functional marker, otoferlin, in the OHCs beyond the maturation period. We also observed a concurrent delay in efferent attachment to the OHCs. Supplementing with TH during the early postnatal period from postnatal day (P) 3 to P4 reversed the defect in type II SGN pruning but did not alter otoferlin expression. Our results show that hypothyroidism causes a defect in the large-scale pruning of afferent type II spiral ganglion neurons in the cochlea, and a delay in efferent attachment and the maturation of otoferlin expression. Our data suggest that the state of maturation of hair cells, as determined by otoferlin expression, may not regulate the pruning of their afferent innervation. PMID:26592716

  16. GLP-1 release and vagal afferent activation mediate the beneficial metabolic and chronotherapeutic effects of D-allulose.

    Science.gov (United States)

    Iwasaki, Yusaku; Sendo, Mio; Dezaki, Katsuya; Hira, Tohru; Sato, Takehiro; Nakata, Masanori; Goswami, Chayon; Aoki, Ryohei; Arai, Takeshi; Kumari, Parmila; Hayakawa, Masaki; Masuda, Chiaki; Okada, Takashi; Hara, Hiroshi; Drucker, Daniel J; Yamada, Yuichiro; Tokuda, Masaaki; Yada, Toshihiko

    2018-01-09

    Overeating and arrhythmic feeding promote obesity and diabetes. Glucagon-like peptide-1 receptor (GLP-1R) agonists are effective anti-obesity drugs but their use is limited by side effects. Here we show that oral administration of the non-calorie sweetener, rare sugar D-allulose (D-psicose), induces GLP-1 release, activates vagal afferent signaling, reduces food intake and promotes glucose tolerance in healthy and obese-diabetic animal models. Subchronic D-allulose administered at the light period (LP) onset ameliorates LP-specific hyperphagia, visceral obesity, and glucose intolerance. These effects are blunted by vagotomy or pharmacological GLP-1R blockade, and by genetic inactivation of GLP-1R signaling in whole body or selectively in vagal afferents. Our results identify D-allulose as prominent GLP-1 releaser that acts via vagal afferents to restrict feeding and hyperglycemia. Furthermore, when administered in a time-specific manner, chronic D-allulose corrects arrhythmic overeating, obesity and diabetes, suggesting that chronotherapeutic modulation of vagal afferent GLP-1R signaling may aid in treating metabolic disorders.

  17. Afferent contribution to locomotor muscle activity during unconstrained overground human walking: an analysis of triceps surae muscle fascicles

    DEFF Research Database (Denmark)

    Klint, Richard af; Cronin, Neil J.; Ishikawa, Masaki

    2010-01-01

    Plantar flexor series elasticity can be used to dissociate muscle fascicle and muscle tendon behaviour and, therefore, afferent feedback during human walking. We used electromyography (EMG) and high speed ultrasonography concomitantly to monitor muscle activity and muscle fascicle behaviour in ni...

  18. Adenosine induces vasoconstriction through Gi-dependent activation of phospholipase C in isolated perfused afferent arterioles of mice

    DEFF Research Database (Denmark)

    Hansen, Pernille B; Castrop, Hayo; Briggs, Josie

    2003-01-01

    -induced vasoconstriction was stable for up to 30 min and was most pronounced in the most distal part of the afferent arterioles. Adenosine did not cause vasoconstriction in arterioles from A1AR-/- mice. Pretreatment with pertussis toxin (PTX) (400 ng/ml) for 2 h blocked the vasoconstricting action of adenosine or N(6...

  19. Comparative pharmacology of cholecystokinin induced activation of cultured vagal afferent neurons from rats and mice.

    Directory of Open Access Journals (Sweden)

    Dallas C Kinch

    Full Text Available Cholecystokinin (CCK facilitates the process of satiation via activation of vagal afferent neurons innervating the upper gastrointestinal tract. Recent findings indicate CCK acts on these neurons via a ruthenium red (RuR sensitive pathway that involves members of the vanilloid (V subfamily of transient receptor potential (TRP channels. To further test this mechanism, the mouse provides an ideal model in which genetic tools could be applied. However, whether CCK acts by similar mechanism(s in mice has not been determined. In the present study we explored the actions of CCK on nodose neurons isolated from Sprague Dawley (SD rat and two strains of mice; C57BL/6 and BalbC using fluorescence-based calcium imaging. With minor exceptions nodose neurons isolated from all species/strains behaved similarly. They all respond to brief depolarization with a large calcium transient. A significant subset of neurons responded to capsaicin (CAP, a TRPV1 agonist, although neurons from C57BL/6 were 10-fold more sensitive to CAP than SD rats or BalbC mice, and a significantly smaller fraction of neurons from BalbC mice responded to CAP. CCK-8 dose-dependently activated a subpopulation of neurons with similar dose dependency, percent responders, and overlap between CCK and CAP responsiveness. In all species/strains CCK-8 induced activation was significantly attenuated (but not completely blocked by pretreatment with the TRPV channel blocker RuR. Surprisingly, the CCK analogue JMV-180, which is reported to have pure antagonistic properties in rat but mixed agonist/antagonist properties in mice, behaved as a pure antagonist to CCK in both rat and mouse neurons. The pure antagonistic action of JMV-180 in this in vitro preparation suggests that prior reported differential effects of JMV-180 on satiation in rats versus mouse must be mediated by a site other than vagal afferent activation.

  20. Perceptual embodiment of prosthetic limbs by transcutaneous electrical nerve stimulation.

    Science.gov (United States)

    Mulvey, Matthew R; Fawkner, Helen J; Radford, Helen E; Johnson, Mark I

    2012-01-01

      In able-bodied participants, it is possible to induce a sense of perceptual embodiment in an artificial hand using a visual-tactile illusion. In amputee patients, electrical stimulation of sensory afferents using transcutaneous electrical nerve stimulation (TENS) has been shown to generate somatic sensations in an amputee's phantom limb(s). However, the effects of TENS on the perceptual embodiment of an artificial limb are not known. Our objective was to investigate the effects of TENS on the perceptual embodiment of an artificial limb in fully intact able-bodied participants.   We used a modified version of the rubber hand illusion presented to 30 able-bodied participants (16 women, 14 men) to convey TENS paresthesia to an artificial hand. TENS electrodes were located over superficial radial nerve on the lateral aspect of the right forearm (1 cm proximal to the wrist), which was hidden from view. TENS intensity was increased to a strong non-painful TENS sensation (electrical paresthesia) was felt beneath the electrodes and projecting into the fingers of the hand. The electrical characteristics of TENS were asymmetric biphasic electrical pulsed waves, continuous pulse pattern, 120 Hz pulse frequency (rate), and 80 µs pulse duration (width).   Participants reported significantly higher intensities of the rubber hand illusion during the two TENS conditions (mean = 5.8, standard deviation = 1.9) compared with the two non-TENS conditions (mean = 4.9, standard deviation = 1.7), p embodiment of an artificial hand. Further exploratory studies involving an amputee population are warranted. © 2011 International Neuromodulation Society.

  1. Angiotensin-(1-7 in Paraventricular Nucleus Contributes to the Enhanced Cardiac Sympathetic Afferent Reflex and Sympathetic Activity in Chronic Heart Failure Rats

    Directory of Open Access Journals (Sweden)

    Xingsheng Ren

    2017-08-01

    Full Text Available Background/Aims: Cardiac sympathetic afferent reflex (CSAR enhancement contributes to exaggerated sympathetic activation in chronic heart failure (CHF. The current study aimed to investigate the roles of angiotensin (Ang-(1-7 in CSAR modulation and sympathetic activation and Ang-(1-7 signaling pathway in paraventricular nucleus of CHF rats. Methods: CHF was induced by coronary artery ligation. Responses of renal sympathetic nerve activity (RSNA and mean arterial pressure (MAP to epicardial application of capsaicin were used to evaluate CSAR in rats with anesthesia. Results: Ang-(1-7 increased RSNA, MAP, CSAR activity, cAMP level, NAD(PH oxidase activity and superoxide anion level more significantly in CHF than in sham-operated rats, while Mas receptor antagonist A-779 had the opposite effects. Moreover, Ang-(1-7 augmented effects of Ang II in CHF rats. The effects of Ang-(1-7 were blocked by A-779, adenylyl cyclase inhibitor SQ22536, protein kinase A inhibitor Rp-cAMP, superoxide anion scavenger tempol and NAD(PH oxidase inhibitor apocynin. Mas and AT1 receptor protein expressions, Ang-(1-7 and Ang II levels in CHF increased. Conclusions: These results indicate that Ang-(1-7 in paraventricular nucleus enhances CSAR and sympathetic output not only by exerting its own effects but also by augmenting the effects of Ang II through Mas receptor in CHF. Endogenous Ang-(1-7/Mas receptor activity contributes to CSAR enhancement and sympathetic activation in CHF, and NAD(PH oxidase-derived superoxide anions and the cAMP-PKA signaling pathway are involved in mediating the effects of Ang-(1-7 in CHF.

  2. Force sensor in simulated skin and neural model mimic tactile SAI afferent spiking response to ramp and hold stimuli.

    Science.gov (United States)

    Kim, Elmer K; Wellnitz, Scott A; Bourdon, Sarah M; Lumpkin, Ellen A; Gerling, Gregory J

    2012-07-23

    The next generation of prosthetic limbs will restore sensory feedback to the nervous system by mimicking how skin mechanoreceptors, innervated by afferents, produce trains of action potentials in response to compressive stimuli. Prior work has addressed building sensors within skin substitutes for robotics, modeling skin mechanics and neural dynamics of mechanotransduction, and predicting response timing of action potentials for vibration. The effort here is unique because it accounts for skin elasticity by measuring force within simulated skin, utilizes few free model parameters for parsimony, and separates parameter fitting and model validation. Additionally, the ramp-and-hold, sustained stimuli used in this work capture the essential features of the everyday task of contacting and holding an object. This systems integration effort computationally replicates the neural firing behavior for a slowly adapting type I (SAI) afferent in its temporally varying response to both intensity and rate of indentation force by combining a physical force sensor, housed in a skin-like substrate, with a mathematical model of neuronal spiking, the leaky integrate-and-fire. Comparison experiments were then conducted using ramp-and-hold stimuli on both the spiking-sensor model and mouse SAI afferents. The model parameters were iteratively fit against recorded SAI interspike intervals (ISI) before validating the model to assess its performance. Model-predicted spike firing compares favorably with that observed for single SAI afferents. As indentation magnitude increases (1.2, 1.3, to 1.4 mm), mean ISI decreases from 98.81 ± 24.73, 54.52 ± 6.94, to 41.11 ± 6.11 ms. Moreover, as rate of ramp-up increases, ISI during ramp-up decreases from 21.85 ± 5.33, 19.98 ± 3.10, to 15.42 ± 2.41 ms. Considering first spikes, the predicted latencies exhibited a decreasing trend as stimulus rate increased, as is observed in afferent recordings. Finally, the SAI afferent's characteristic response

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

    Science.gov (United States)

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

    2017-05-01

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

  4. Altered brain morphometry in carpal tunnel syndrome is associated with median nerve pathology☆☆☆

    Science.gov (United States)

    Maeda, Yumi; Kettner, Norman; Sheehan, James; Kim, Jieun; Cina, Stephen; Malatesta, Cristina; Gerber, Jessica; McManus, Claire; Mezzacappa, Pia; Morse, Leslie R.; Audette, Joseph; Napadow, Vitaly

    2013-01-01

    Objective Carpal tunnel syndrome (CTS) is a common median nerve entrapment neuropathy characterized by pain, paresthesias, diminished peripheral nerve conduction velocity (NCV) and maladaptive functional brain neuroplasticity. We evaluated structural reorganization in brain gray matter (GM) and white matter (WM) and whether such plasticity is linked to altered median nerve function in CTS. Methods We performed NCV testing, T1-weighted structural MRI, and diffusion tensor imaging (DTI) in 28 CTS and 28 age-matched healthy controls (HC). Voxel-based morphometry (VBM) contrasted regional GM volume for CTS versus HC. Significant clusters were correlated with clinical metrics and served as seeds to define associated WM tracts using DTI data and probabilistic tractography. Within these WM tracts, fractional anisotropy (FA), axial (AD) and radial (RD) diffusivity were evaluated for group differences and correlations with clinical metrics. Results For CTS subjects, GM volume was significantly reduced in contralesional S1 (hand-area), pulvinar and frontal pole. GM volume in contralesional S1 correlated with median NCV. NCV was also correlated with RD and was negatively correlated with FA within U-fiber cortico-cortical association tracts identified from the contralesional S1 VBM seed. Conclusions Our study identified clear morphometric changes in the CTS brain. This central morphometric change is likely secondary to peripheral nerve pathology and altered somatosensory afference. Enhanced axonal coherence and myelination within cortico-cortical tracts connecting primary somatosensory and motor areas may accompany peripheral nerve deafferentation. As structural plasticity was correlated with NCV and not symptomatology, the former may be a better determinant of appropriate clinical intervention for CTS, including surgery. PMID:23799199

  5. HuD-mediated distinct BDNF regulatory pathways promote regeneration after nerve injury.

    Science.gov (United States)

    Sanna, Maria Domenica; Ghelardini, Carla; Galeotti, Nicoletta

    2017-03-15

    Up-regulation of brain-derived neurotrophic factor (BDNF) synthesis is an important mechanism of peripheral nerve regeneration after injury. However, the cellular and molecular mechanisms underlying this process are not fully understood. This study examines the role of BDNF in the spared nerve injury (SNI) mice model. Protein expression and cellular localization were investigated in the dorsal root ganglia (DRG) and spinal cord by western blotting and immunofluorescence experiments respectively. BDNF protein was markedly increased 3 and 7days post-injury in the spinal cord and DRG. Following nerve injury sensory neurons produce molecules to promote regeneration, such as growth-associated protein 43 (GAP-43) and cytoskeletal proteins. Our results show that the expression of GAP-43 was increased in the DRG and spinal cord while, an increased of p-NFH content was detected in the spinal cord, with no modification in the DRG. Both events were counteracted by the administration of an anti-BDNF antibody. In DRG of SNI mice we also detected an increase of HuD expression, a RNA-binding protein known to stabilize BDNF and GAP-43 mRNA. Silencing of HuD prevented the nerve injury-induced BDNF and GAP-43 enhanced expression in the DRG. HuD-mediated BDNF synthesis in the primary sensory neurons, is followed by an anterograde transport of the neurotrophin to the central terminals of the primary afferents in the spinal dorsal horn, to modulate GAP-43 and NFH activation. Our data suggest that BDNF, GAP-43 and p-NFH proteins increase are linked events required for the enhanced regeneration after nerve injury. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Cardiac-locked bursts of muscle sympathetic nerve activity are absent in familial dysautonomia

    Science.gov (United States)

    Macefield, Vaughan G; Norcliffe-Kaufmann, Lucy; Axelrod, Felicia B; Kaufmann, Horacio

    2013-01-01

    Familial dysautonomia (Riley–Day syndrome) is an hereditary sensory and autonomic neuropathy (HSAN type III), expressed at birth, that is associated with reduced pain and temperature sensibilities and absent baroreflexes, causing orthostatic hypotension as well as labile blood pressure that increases markedly during emotional excitement. Given the apparent absence of functional baroreceptor afferents, we tested the hypothesis that the normal cardiac-locked bursts of muscle sympathetic nerve activity (MSNA) are absent in patients with familial dysautonomia. Tungsten microelectrodes were inserted percutaneously into muscle or cutaneous fascicles of the common peroneal nerve in 12 patients with familial dysautonomia. Spontaneous bursts of MSNA were absent in all patients, but in five patients we found evidence of tonically firing sympathetic neurones, with no cardiac rhythmicity, that increased their spontaneous discharge during emotional arousal but not during a manoeuvre that unloads the baroreceptors. Conversely, skin sympathetic nerve activity (SSNA), recorded in four patients, appeared normal. We conclude that the loss of phasic bursts of MSNA and the loss of baroreflex modulation of muscle vasoconstrictor drive contributes to the poor control of blood pressure in familial dysautonomia, and that the increase in tonic firing of muscle vasoconstrictor neurones contributes to the increase in blood pressure during emotional excitement. PMID:23165765

  7. Functional assessment of sciatic nerve reconstruction : Biodegradable poly (DLLA-epsilon-CL) nerve guides versus autologous nerve grafts

    NARCIS (Netherlands)

    Meek, MF; Dijkstra, [No Value; Den Dunnen, WFA; Ijkema-Paassen, J; Schakenraad, JM; Gramsbergen, A; Robinson, PH

    1999-01-01

    The aim of this study was to compare functional nerve recovery after reconstruction with a biodegradable p(DLLA-epsilon-CL) nerve guide filled with modified denatured muscle tissue (MDMT), or an autologous nerve graft. We evaluated nerve recovery using walking track analysis (measurement of the

  8. [Development of peripheral nerve surgery].

    Science.gov (United States)

    Sames, M

    1998-03-01

    In the submitted review the author deals with the development of peripheral nerve surgery (PN) from ancient times to the present time incl. hithero unpublished details. He analyses in great detail the period of the last 40 years which is divided into three stages--the mechanical, biological period and the period of neurotrophism. From the Second World War to the sixties the period bears the term mechanical. The results of reinnervation during this period were not satisfactory as the nerves were connected without the use of a microscope, in major defects they were connected under considerable traction and the only criterion was the resistance against dehiscence. Significant improvement of results of regeneration of PN was recorded during the biological period. Mechanical ideas were overcome and biological and physiological reactions of the peripheral nerves were taken into account. Suture of nerves under traction was refuted and into clinical practice the surgical microscope, microsurgical technique and microsurgical autotransplantation with a nervous graft were introduced. The anatomical structure of the nerve with a plexiform pattern of the fascicles became however the limitation of surgical methods. After discovery of NGF (nerve growth factor) we can speak of the onset of a new period, neurotrophism. In laboratory experiments many substances are studied and theoretically new non-surgical possibilities how to promote regeneration lie ahead. However they cannot be applied yet in clinical practice. In injuries of peripheral nerves the only correct reconstruction method is still microsuture of the nerve and in case of losses microsurgical autotransplantation using a nerve graft.

  9. Optical coherence tomography of the newborn airway.

    Science.gov (United States)

    Ridgway, James M; Su, Jianping; Wright, Ryan; Guo, Shuguang; Kim, David C; Barretto, Roberto; Ahuja, Gurpreet; Sepehr, Ali; Perez, Jorge; Sills, Jack H; Chen, Zhongping; Wong, Brian J F

    2008-05-01

    Acquired subglottic stenosis in a newborn is often associated with prolonged endotracheal intubation. This condition is generally diagnosed during operative endoscopy after airway injury has occurred. Unfortunately, endoscopy is unable to characterize the submucosal changes observed in such airway injuries. Other modalities, such as magnetic resonance imaging, computed tomography, and ultrasound, do not possess the necessary level of resolution to differentiate scar, neocartilage, and edema. Optical coherence tomography (OCT) is an imaging modality that produces high-resolution, cross-sectional images of living tissue (8 to 20 microm). We examined the ability of this noninvasive technique to characterize the newborn airway in a prospective clinical trial. Twelve newborn patients who required ventilatory support underwent OCT airway imaging. Comparative analysis of intubated and non-intubated states was performed. Imaging of the supraglottis, glottis, subglottis, and trachea was performed in 12 patients, revealing unique tissue characteristics as related to turbidity, signal backscattering, and architecture. Multiple structures were identified, including the vocal folds, cricoid cartilage, tracheal rings, ducts, glands, and vessels. Optical coherence tomography clearly identifies in vivo tissue layers and regional architecture while offering detailed information concerning tissue microstructures. The diagnostic potential of this technology makes OCT a promising modality in the study and surveillance of the neonatal airway.

  10. Regional aerosol deposition in human upper airways

    Energy Technology Data Exchange (ETDEWEB)

    Swift, D.L.

    1992-11-01

    Laboratory experimental studies were carried out to investigate the factors influencing the deposition of aerosols ranging in size from 1 nm to 10 [mu]m in the human nasal, oral, pharyngeal and laryngeal airways. These experimental studies were performed in replicate upper airway physical models and in human volunteer subjects. New replicate models of the oral passage of an infant, the oral passage of an adult at two openings and the combined nasal and oral airways of an adult were constructed during the period, adding to the existing models of adult, child and infant nasal and oral airways models. Deposition studies in the adult oral and adult nasal models were performed under simulated cyclic flow conditions with 1 nm particles to compare with previously measured constant flow studies. Similar studies with inertial particles (1--10 [mu]m diameter) were performed with the adult nasal model; in both instances, results with cyclic flow were similar to constant flow results using a simple average flow rate based on inspiratory volume and time of inspiration. Human subject studies were performed with particle sizes 5--20 nm for nasal inspiration; preliminary analysis shows good agreement with model studies at several representative flow rates. Nasal inspiratory inertial deposition of 1--4 [mu]m diameter particles was measured in several adults as a function of airway dimensions; dimensional changes of the valve area by decongestion did not produce concomitant deposition changes.

  11. Silibinin attenuates allergic airway inflammation in mice

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yun Ho [Department of Anatomy, Medical School, Institute for Medical Sciences, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Jin, Guang Yu [Department of Radiology, Yanbian University Hospital, YanJi 133002 (China); Guo, Hui Shu [Centralab, The First Affiliated Hospital of Dalian Medical University, Dalian 116011 (China); Piao, Hong Mei [Department of Respiratory Medicine, Yanbian University Hospital, YanJi 133000 (China); Li, Liang chang; Li, Guang Zhao [Department of Anatomy and Histology and Embryology, Yanbian University School of Basic Medical Sciences, 977 Gongyuan Road, YanJi 133002, Jilin (China); Lin, Zhen Hua [Department of Pathology, Yanbian University School of Basic Medical Sciences, YanJi 133000 (China); Yan, Guang Hai, E-mail: ghyan@ybu.edu.cn [Department of Anatomy and Histology and Embryology, Yanbian University School of Basic Medical Sciences, 977 Gongyuan Road, YanJi 133002, Jilin (China)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer Silibinin diminishes ovalbumin-induced inflammatory reactions in the mouse lung. Black-Right-Pointing-Pointer Silibinin reduces the levels of various cytokines into the lung of allergic mice. Black-Right-Pointing-Pointer Silibinin prevents the development of airway hyperresponsiveness in allergic mice. Black-Right-Pointing-Pointer Silibinin suppresses NF-{kappa}B transcriptional activity. -- Abstract: Allergic asthma is a chronic inflammatory disease regulated by coordination of T-helper2 (Th2) type cytokines and inflammatory signal molecules. Silibinin is one of the main flavonoids produced by milk thistle, which is reported to inhibit the inflammatory response by suppressing the nuclear factor-kappa B (NF-{kappa}B) pathway. Because NF-{kappa}B activation plays a pivotal role in the pathogenesis of allergic inflammation, we have investigated the effect of silibinin on a mouse ovalbumin (OVA)-induced asthma model. Airway hyperresponsiveness, cytokines levels, and eosinophilic infiltration were analyzed in bronchoalveolar lavage fluid and lung tissue. Pretreatment of silibinin significantly inhibited airway inflammatory cell recruitment and peribronchiolar inflammation and reduced the production of various cytokines in bronchoalveolar fluid. In addition, silibinin prevented the development of airway hyperresponsiveness and attenuated the OVA challenge-induced NF-{kappa}B activation. These findings indicate that silibinin protects against OVA-induced airway inflammation, at least in part via downregulation of NF-{kappa}B activity. Our data support the utility of silibinin as a potential medicine for the treatment of asthma.

  12. Unexpected difficult airway with hypogonadotropic hypogonadism

    Directory of Open Access Journals (Sweden)

    Yaman F

    2014-04-01

    Full Text Available Ferda Yaman,1 Bengi Arslan,2 Ercan Yuvanç,3 Ünase Büyükkoçak1 1Anesthesiology and Reanimation Department, 2Otorhinolaryngology Head and Neck Surgery Department, 3Urology Department, Faculty of Medicine, Kirikkale University, Kirikkale, Turkey Background: A critical aspect of safe general anesthesia is providing adequate ventilation and oxygenation. Failed endotracheal intubation and inadequate ventilation with insufficient oxygenation may lead to serious complications, even death. Anesthesiologists rarely encounter unexpected difficult airway problems in daily routine. Management of an unexpectedly difficult airway consists of laryngeal mask ventilation, gum-elastic bougie and video laryngoscopy-assisted intubation. Gum-elastic bougie is the easiest and cheapest tool used in case of an unexpected difficult intubation occurring in the operating room. Case: A 53-year-old male patient with hypogonadotropic hypogonadism presented as an unexpected difficult intubation after the induction of anesthesia. No pathological finding or predictor of difficult intubation was present. In addition, bag-mask ventilation was poor and inadequate. The patient was finally successfully intubated with a gum-elastic bougie. Conclusion: A difficult airway has been described in patients with a variety of endocrine disorders, including pituitary diseases, but not with hypogonadism. There may be an unrevealed relationship between hypogonadism and difficult airway. Gum-elastic bougie is still the most attainable and effective tool in the operation room in this situation. Keywords: airway management, intubation, hypogonadism

  13. What's left of the mirror illusion when the mirror can no longer be seen? Bilateral integration of proprioceptive afferents!

    Science.gov (United States)

    Chancel, Marie; Kavounoudias, Anne; Guerraz, Michel

    2017-10-24

    Recent data suggest that manipulating the muscle afferents of one arm affects both ipsilateral and contralateral perceptual estimates. Here, we used the mirror paradigm to study the bimanual integration of kinesthetic muscle afferents. The reflection of a moving hand in a mirror positioned in the sagittal plane creates an illusion of symmetrical bimanual movement. Although vision clearly has a role in kinesthesia, its role in the mirror illusion might have been overestimated. Conversely, the role of bimanual integration of muscle afferents might have been underestimated. We hypothesized that muscle-proprioceptive afferents of the passively displaced arm (the image of which was reflected in the mirror) are involved in this illusion. We evoked in 19 healthy adult participants the mirror illusion by displacing passively their left arm, the image of which was reflected in the mirror. Once participants experienced the illusion that their hidden right arm was moving, we then either occluded their view of the mirror (using occlusive glasses) and/or prevent the passive left arm displacement. Participants' illusion characteristics (duration and kinematic) under these conditions were compared with classical mirror illusion (without visual occlusion). We found that as long as the arm was still moving, the kinesthetic illusion decayed slowly after visual occlusion. These findings suggest that the mirror illusion results from the combination of visuo-proprioceptive signals from the two arms and is not purely visual in origin. Our findings also support the more general concept whereby proprioceptive afferents are integrated bilaterally for the purpose of kinesthesia during bimanual tasks. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  14. Improved Ventilatory Efficiency with Locomotor Muscle Afferent Inhibition is Strongly Associated with Leg Composition in Heart Failure.

    Science.gov (United States)

    Keller-Ross, Manda L; Johnson, Bruce D; Carter, Rickey E; Joyner, Michael J; Eisenach, John H; Curry, Timothy B; Olson, Thomas P

    2016-01-01

    Skeletal muscle atrophy contributes to increased afferent feedback (group III and IV) and may influence ventilatory control (high VE/VCO2 slope) in heart failure (HF). This study examined the influence of muscle mass on the change in VE/VCO2 with afferent neural block during exercise in HF. 17 participants [9 HF (60±6 yrs) and 8 controls (CTL) (63±7 yrs, mean±SD)] completed 3 sessions. Session 1: dual energy x-ray absorptiometry and graded cycle exercise to volitional fatigue. Sessions 2 and 3: 5 min of constant-work cycle exercise (65% of peak power) randomized to lumbar intrathecal injection of fentanyl (afferent blockade) or placebo. Ventilation (VE) and gas exchange (oxygen consumption, VO2; carbon dioxide production, VCO2) were measured. Peak work and VO2 were lower in HF (pLeg fat was greater in HF (34.4±3.0 and 26.3±1.8%) and leg muscle mass was lower in HF (63.0±2.8 and 70.4±1.8%, respectively, pleg muscle mass (r2=0.58, pleg fat mass (r2=0.73, pleg muscle mass had the greatest improvement in VE/VCO2 with afferent blockade with leg fat mass being the only predictor for the improvement in VE/VCO2 slope. Both leg muscle mass and fat mass are important contributors to ventilatory abnormalities and strongly associated to improvements in VE/VCO2 slope with locomotor afferent inhibition in HF. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Outcome of axillary nerve injuries treated with nerve grafts.

    Science.gov (United States)

    Okazaki, M; Al-Shawi, A; Gschwind, C R; Warwick, D J; Tonkin, M A

    2011-09-01

    This study evaluates the outcome of axillary nerve injuries treated with nerve grafting. Thirty-six patients were retrospectively reviewed after a mean of 53 months (minimum 12 months). The mean interval from injury to surgery was 6.5 months. Recovery of deltoid function was assessed by the power of both abduction and retropulsion, the deltoid bulk and extension lag. The deltoid bulk was almost symmetrical in nine of 34 cases, good in 22 and wasted in three. Grade M4 or M5* was achieved in 30 of 35 for abduction and in 32 of 35 for retropulsion. There was an extension lag in four patients. Deltoid bulk continued to improve with a longer follow-up following surgery. Nerve grafting to the axillary nerve is a reliable method of regaining deltoid function when the lesion is distal to its origin from the posterior cord.

  16. Central Mandibular Nerve Sheath Myxoma

    Directory of Open Access Journals (Sweden)

    Narges Ghazi

    2018-03-01

    Full Text Available Nerve sheath myxoma has been described as a rare neural tumor arising from Schwann cells. It is observed most frequently in the central area of the face, neck and upper extremities. In the past the term neurothekeoma was used as synonym for nerve sheath myxoma but according to new reports, they are separate entities which can be confirmed by immunohistochemistry as in our case. Oral involvement of this tumor is extremely rare. Here, we present an unusual case of nerve sheath myxoma in the mandible of a 22-year old female patient. This case appears to be the first myxomatous variant which is centrally located in the mandible.

  17. Nerve damage associated with inferior alveolar nerve blocks.

    Science.gov (United States)

    Pogrel, M A; Bryan, J; Regezi, J

    1995-08-01

    The authors reviewed 12 cases in which altered sensation occurred in the distribution of the inferior alveolar or lingual nerves following injection of a local anesthetic for restorative treatment only. Most patients suffered only partial damage, but recovery was poor. The exact mechanism of the nerve damage is unknown, but a number of theories are proposed. The extent of this problem is also unknown, but many more cases probably exist than have been reported to date.

  18. Nerve Transfers for Treatment of Isolated Axillary Nerve Injuries

    OpenAIRE

    Wheelock, Margie; Clark, Tod A; Giuffre, Jennifer L

    2015-01-01

    Almost one-half of all dislocations involve the shoulder and may also involve the axillary nerves, which may influence functional recovery and result in persistent shoulder neuropathy. Although individuals with intact rotator cuffs may be able to compensate for axillary nerve dysfunction, the injury may become problematic in later years, especially given the increasing incidence of rotator cuff tears in aging populations, thus placing increased importance on the immediate success of acute man...

  19. Corticosteroids for treating nerve damage in leprosy

    NARCIS (Netherlands)

    N.H.J. van Veen (Natasja); P.G. Nicholls (Peter); W.C.S. Smith (Cairns); J.H. Richardus (Jan Hendrik)

    2007-01-01

    textabstractBackground: Leprosy causes nerve damage which can result in nerve function impairment and disability. Corticosteroids are commonly used for treating nerve damage, although the long-term effect is uncertain. Objectives: To assess the effects of corticosteroids on nerve damage in leprosy.

  20. Host–microbe interactions in distal airways: relevance to chronic airway diseases

    Directory of Open Access Journals (Sweden)

    Clémence Martin

    2015-03-01

    Full Text Available This article is the summary of a workshop, which took place in November 2013, on the roles of microorganisms in chronic respiratory diseases. Until recently, it was assumed that lower airways were sterile in healthy individuals. However, it has long been acknowledged that microorganisms could be identified in distal airway secretions from patients with various respiratory diseases, including cystic fibrosis (CF and non-CF bronchiectasis, chronic obstructive pulmonary disease, asthma and other chronic airway diseases (e.g. post-transplantation bronchiolitis obliterans. These microorganisms were sometimes considered as infectious agents that triggered host immune responses and contributed to disease onset and/or progression; alternatively, microorganisms were often considered as colonisers, which were considered unlikely to play roles in disease pathophysiology. These concepts were developed at a time when the identification of microorganisms relied on culture-based methods. Importantly, the majority of microorganisms cannot be cultured using conventional methods, and the use of novel culture-independent methods that rely on the identification of microorganism genomes has revealed that healthy distal airways display a complex flora called the airway microbiota. The present article reviews some aspects of current literature on host–microbe (mostly bacteria and viruses interactions in healthy and diseased airways, with a special focus on distal airways.

  1. Airway Science curriculum demonstration project : summary of initial evaluation findings.

    Science.gov (United States)

    1988-10-01

    The performance, perceptions, and characteristics of Airway Science hires were compared with those of traditional hires. As of May 12, 1987. a total of 197 Airway Science candidates had been selected into FAA occupations. The demographic characterist...

  2. Unmet needs in severe chronic upper airway disease (SCUAD)

    NARCIS (Netherlands)

    Bousquet, Jean; Bachert, Claus; Canonica, Giorgio W.; Casale, Thomas B.; Cruz, Alvaro A.; Lockey, Richard J.; Zuberbier, Torsten; Akdis, C. A.; Baena-Cagnani, C.; Bateman, E. D.; Bonini, S.; Boulet, L. P.; Bousquet, P. J.; Burney, P. G.; Cardell, L. O.; Carlsen, K. H.; Carsten-Jensens, B.; Chen, Y.; Chkhartishvili, E.; Chuchalin, A.; Cox, L.; Custovic, A.; Dahl, R.; Delgado, L.; Demoly, P.; Denburg, J.; Dolen, W. K.; Dubakiene, R.; El-Gamal, Y.; Fokkens, W. J.; Fukuda, T.; Gerth van Wiijk, R.; Gjomarkaj, M.; Haahtela, T.; Hamelmann, E.; Holgate, S. T.; Howarth, P.; Ivancevich, J. C.; Jensen-Jarolim, E.; Kalayci, O.; Kaliner, M.; Kim, Y. Y.; Kowalski, M. L.; Le, L.; Lee, B. W.; Leynaert, B.; Lodrup-Carlsen, K.; Meltzer, E. O.; Mohammad, Y.; Morais-Almeida, M.; Mullol, J.; Nizankowska-Mogilnicka, E.; O'Hehir, R. E.; Ohta, K.; Okamoto, Y.; Papadopoulos, N.; Park, H. S.; Passalacqua, G.; Pawankar, R.; Popov, T.; Potter, P.; Price, D.; Rabe, K. F.; Rodriguez Perez, N.; Romano, A.; Rosenwasser, L.; Ryan, D.; Salapatas, M.; Sanchez-Borges, M.; Scadding, G.; Schmid-Grendelmeier, P. D.; Simons, F. E. R.; Todo-Bom, A.; Toskala, E.; Valovirta, E.; van Cauwenberge, P.; van Weel, C.; Vandenplas, O.; Vichyanond, P.; Wang, D. Y.; Wickman, M.; Yorgancioglu, A.; Yusuf, O.; Zar, H.; Zhong, N.; Zitt, M.; Zock, P.

    2009-01-01

    Although the majority of patients with chronic upper airway diseases have controlled symptoms during treatment, many patients have severe chronic upper airway diseases (SCUADs). SCUAD defines those patients whose symptoms are inadequately controlled despite adequate (ie, effective, safe, and

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

    Science.gov (United States)

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

    2009-06-01

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

  4. Use of tubulization (nerve conduits in repairing nerve defects in children

    Directory of Open Access Journals (Sweden)

    Filippo Maria Sénès

    2015-01-01

    Conclusions: In peripheral nerve repairing in children by using nerve conduits, the outcome has been widely effective even when dealing with mixed and motor nerve, thus nerve tubulization might be considered as an alternative to nerve grafting. Conversely, considering the uncertain result obtained in brachial plexus repairing, the conduits cannot be considered as afirst choice of treatment in brachial plexus reconstruction.

  5. Poly(DL-lactide-epsilon-caprolactone) nerve guides perform better than autologous nerve grafts

    NARCIS (Netherlands)

    DenDunnen, WFA; VanderLei, B; Schakenraad, JM; Stokroos, [No Value; Blaauw, E; Pennings, AJ; Robinson, PH; Bartels, H.

    1996-01-01

    The aim of this study was to compare the speed and quality of nerve regeneration after reconstruction using a biodegradable nerve guide or an autologous nerve graft. We evaluated nerve regeneration using light microscopy, transmission electron microscopy and morphometric analysis. Nerve regeneration

  6. Decreased Nerve Conduction Velocity in Football Players

    Directory of Open Access Journals (Sweden)

    Daryoush Didehdar

    2014-06-01

    Full Text Available Background: Lower limbs nerves are exposed to mechanical injuries in the football players and the purpose of this study is to evaluate the influence of football on the lower leg nerves. Materials and Methods: Nerve conduction studies were done on 35 male college students (20 football players, 15 non active during 2006 to 2007 in the Shiraz rehabilitation faculty. Standard nerve conduction techniques using to evaluate dominant and non dominant lower limb nerves. Results: The motor latency of deep peroneal and tibial nerves of dominant leg of football players and sensory latency of superficial peroneal, tibial and compound nerve action potential of tibial nerve of both leg in football players were significantly prolonged (p<0.05. Motor and sensory nerve conduction velocity of tibial and common peroneal in football players were significant delayed (p<0.05. Conclusion: It is concluded that football is sport with high contact and it causes sub-clinical neuropathies due to nerve entrapment.

  7. Light and electron microscopy of contacts between primary afferent fibres and neurones with axons ascending the dorsal columns of the feline spinal cord.

    Science.gov (United States)

    Maxwell, D J; Koerber, H R; Bannatyne, B A

    1985-10-01

    In addition to primary afferent fibres, the dorsal columns of the cat spinal cord contain ascending second-order axons which project to the dorsal column nuclei. The aim of the present study was to obtain morphological evidence that certain primary afferent axons form monosynaptic contacts with cells of origin of this postsynaptic dorsal column pathway. In ten adult cats, neurones with axons ascending the dorsal columns were retrogradely labelled with horseradish peroxidase using a pellet implantation method in the thoracic dorsal columns. In the lumbosacral regions of the same animals, primary afferent fibres were labelled intra-axonally with ionophoretic application of horseradish peroxidase. Tissue containing labelled axons was prepared for light and combined light and electron microscopy. Ultrastructural examination demonstrated that slowly adapting (Type I), hair follicle, Pacinian corpuscle and group Ia muscle spindle afferents formed monosynaptic contacts with labelled cells and light microscopical analysis suggested that they also received monosynaptic input from rapidly adapting (Krause) afferents. This evidence suggests that sensory information from large-diameter cutaneous and muscle spindle afferent fibres is conveyed disynaptically via the postsynaptic dorsal column pathway to the dorsal column nuclei. Some of the input to this pathway is probably modified in the spinal cord as the majority of primary afferent boutons forming monosynaptic contacts were postsynaptic to other axon terminals. The postsynaptic dorsal column system appears to constitute a major somatosensory pathway in the cat.

  8. Dilemmas, Confusion, and Misconceptions Related to Small Airways Directed Therapy.

    Science.gov (United States)

    Lavorini, Federico; Pedersen, Søren; Usmani, Omar S

    2017-06-01

    During the past decade, there has been increasing evidence that the small airways (ie, airways misconceptions related to small airways directed therapy. To this end, we have reviewed all studies on small-particle aerosol therapy systematically to address the dilemmas, confusion, and misconceptions related to small airways directed therapy. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  9. Large Extremity Peripheral Nerve Repair

    Science.gov (United States)

    2015-10-01

    decellularized nerve allograft for inferior alveolar nerve reconstruction: a case report. Journal of oral and maxillofacial surgery : official journal of...the American Association of Oral and Maxillofacial Surgeons. 2011 Feb;69(2):550-3. PubMed PMID: 21145638. Epub 2010/12/15. eng. 16. Gunn S, Cosetti M...Massachusetts General Hospital (protocol #2012N000117) and was also granted ACURO approval on 11/19/2012. Task 2b. Rodent surgeries for segmental deficit

  10. Impossible Airway Requiring Venovenous Bypass for Tracheostomy

    Directory of Open Access Journals (Sweden)

    Johnathan Gardes

    2012-01-01

    Full Text Available The elective surgical airway is the definitive management for a tracheal stenotic lesion that is not a candidate for tracheal resection, or who has failed multiple-tracheal dilations. This case report details the management of a patient who has failed an elective awake tracheostomy secondary to the inability to be intubated as well as severe scar tissue at the surgical site. A combination of regional anesthesia and venovenous bypass is used to facilitate the surgical airway management of this patient. Cerebral oximetry and a multidisciplinary team approach aid in early detection of an oxygenation issue, as well as the emergent intervention that preserved this patient’s life.

  11. Water permeability in human airway epithelium

    DEFF Research Database (Denmark)

    Pedersen, Peter Steen; Procida, Kristina; Larsen, Per Leganger

    2005-01-01

    of those seen in AQP-associated water transport. Together, these results indicate the presence of an AQP in the apical membrane of the spheroids. Notably, identical values for P(f) were found in CF and non-CF airway preparations, as was the case also for the calculated spontaneous fluid absorption rates.......Osmotic water permeability (P(f)) was studied in spheroid-shaped human airway epithelia explants derived from nasal polyps by the use of a new improved tissue collection and isolation procedure. The fluid-filled spheroids were lined with a single cell layer with the ciliated apical cell membrane...

  12. A novel method of lengthening the accessory nerve for direct coaptation during nerve repair and nerve transfer procedures.

    Science.gov (United States)

    Tubbs, R Shane; Maldonado, Andrés A; Stoves, Yolanda; Fries, Fabian N; Li, Rong; Loukas, Marios; Oskouian, Rod J; Spinner, Robert J

    2018-01-01

    OBJECTIVE The accessory nerve is frequently repaired or used for nerve transfer. The length of accessory nerve available is often insufficient or marginal (under tension) for allowing direct coaptation during nerve repair or nerve transfer (neurotization), necessitating an interpositional graft. An attractive maneuver would facilitate lengthening of the accessory nerve for direct coaptation. The aim of the present study was to identify an anatomical method for such lengthening. METHODS In 20 adult cadavers, the C-2 or C-3 connections to the accessory nerve were identified medial to the sternocleidomastoid (SCM) muscle and the anatomy of the accessory nerve/cervical nerve fibers within the SCM was documented. The cervical nerve connections were cut. Lengths of the accessory nerve were measured. Samples of the cut C-2 and C-3 nerves were examined using immunohistochemistry. RESULTS The anatomy and adjacent neural connections within the SCM are complicated. However, after the accessory nerve was "detethered" from within the SCM and following transection, the additional length of the accessory nerve increased from a mean of 6 cm to a mean of 10.5 cm (increase of 4.5 cm) after cutting the C-2 connections, and from a mean of 6 cm to a mean length of 9 cm (increase of 3.5 cm) after cutting the C-3 connections. The additional length of accessory nerve even allowed direct repair of an infraclavicular target (i.e., the proximal musculocutaneous nerve). The cervical nerve connections were shown not to contain motor fibers. CONCLUSIONS An additional length of the accessory nerve made available in the posterior cervical triangle can facilitate direct repair or neurotization procedures, thus eliminating the need for an interpositional nerve graft, decreasing the time/distance for regeneration and potentially improving clinical outcomes.

  13. Unilateral traumatic oculomotor nerve paralysis

    International Nuclear Information System (INIS)

    Asari, Syoji; Satoh, Toru; Yamamoto, Yuji

    1982-01-01

    The present authors report a case of unilateral traumatic oculomotor nerve paralysis which shows interesting CT findings which suggest its mechanism. A 60-year-old woman was admitted to our hospital with a cerebral concussion soon after a traffic accident. A CT scan was performed soon after admission. A high-density spot was noted at the medial aspect of the left cerebral peduncle, where the oculomotor nerve emerged from the midbrain, and an irregular, slender, high-density area was delineated in the right dorsolateral surface of the midbrain. Although the right hemiparesis had already improved by the next morning, the function of the left oculomotor nerve has been completely disturbed for the three months since the injury. In our case, it is speculated that an avulsion of the left oculomotor nerve rootlet occurred at the time of impact as the mechanism of the oculomotor nerve paralysis. A CT taken soon after the head injury showed a high-density spot; this was considered to be a hemorrhage occurring because of the avulsion of the nerve rootlet at the medial surface of the cerebral peduncle. (J.P.N.)

  14. Rigid fibrescope Bonfils: use in simulated difficult airway by novices

    Directory of Open Access Journals (Sweden)

    Piepho Tim

    2009-07-01

    Full Text Available Abstract Background The Bonfils intubation fibrescope is a promising alternative device for securing the airway. We examined the success rate of intubation and the ease of use in standardized simulated difficult airway scenarios by physicians. We compared the Bonfils to a classical laryngoscope with Macintosh blade. Methods 30 physicians untrained in the use of rigid fibrescopes but experienced in airway management performed endotracheal intubation in an airway manikin (SimMan, Laerdal, Kent, UK with three different airway conditions. We evaluated the success rate using the Bonfils (Karl Storz, Tuttlingen, Germany or the Macintosh laryngoscope, the time needed for securing the airway, and subjective rating of both techniques. Results In normal airway all intubations were successful using laryngoscope (100% vs. 82% using the Bonfils (p Conclusion The Bonfils can be successfully used by physicians unfamiliar with this technique in an airway manikin. The airway could be secured with at least the same success rate as using a Macintosh laryngoscope in difficult airway scenarios. Use of the Bonfils did not delay intubation in the presence of a difficult airway. These results indicate that intensive special training is advised to use the Bonfils effectively in airway management.

  15. Occupational upper airway disease: how work affects the nose

    NARCIS (Netherlands)

    Hox, V.; Steelant, B.; Fokkens, W.; Nemery, B.; Hellings, P. W.

    2014-01-01

    Chronic inflammation of the upper airways is common and can arbitrarily be divided into rhinitis and rhinosinusitis. Infection and allergy represent two well-characterized and most frequently diagnosed etiologies of upper airway inflammation. Persistent upper airway inflammation caused by agents

  16. Airway management: A survey of training and practices of Nigerian ...

    African Journals Online (AJOL)

    Background: Airway management is an integral part of anesthetist's training and clinical practice. Studies have suggested that opportunities for anesthesia trainees to ... There is increased use of simple airway devices with deskilling in complex airway management. Resource limitation means that very few individuals have ...

  17. Incidence and risk factors for postoperative lingual neuropraxia following airway instrumentation: A retrospective matched case-control study.

    Directory of Open Access Journals (Sweden)

    Yi-Kai Su

    Full Text Available Lingual nerve injury or neuropraxia is a rare but potentially serious perioperative complication following airway instrumentation during general anesthesia. This study explored the the incidence and perioperative risk factors for lingual nerve injury in patients receiving laryngeal mask (LMA or endotracheal (ETGA general anesthesia in a single center experience.All surgical patients in our hospital who received LMA or ETGA from 2009 to 2013 were included, and potential perioperative risk factors were compared. Matched controls were randomly selected (in 1:5 ratio from the same database in non-case patients. A total of 36 patients in the records had reported experiencing tongue numbness after anesthesia in this study. Compared with the non-case surgical population (n = 54314, patients with tongue numbness were significantly younger (52.2±19.5 vs 42.0±14.5; P = 0.002 and reported lower ASA physical statuses (2.3±0.7 vs 1.6±0.6; P<0.001. Patient gender, anesthesia technique used, and airway device type (LMA or ETGA did not differ significantly across the two groups. A significantly higher proportion of patients underwent operations of the head-and-neck region (38.9 vs 15.6%; P = 0.002 developed tongue numbness after anesthesia. Multivariate logistic regression analysis indicated that head-and-neck operations remained the most significant independent risk factor for postoperative lingual nerve injury (AOR 7.63; 95% CI 2.03-28.70.The overall incidence rate of postoperative lingual neuropraxy was 0.066% in patients receiving general anesthesia with airway device in place. Young and generally healthy patients receiving head-and-neck operation are at higher risk in developing postoperative lingual neuropraxy. Attention should be particularly exercised to reduce the pressure of endotracheal tube or laryngeal mask on the tongue during head-and-neck operation to avert the occurrence of postoperative lingual neuropraxy.

  18. A randomised trial comparing the laryngeal mask airway Supreme™ with the laryngeal mask airway Unique™ in children.

    Science.gov (United States)

    Jagannathan, N; Sohn, L E; Sawardekar, A; Chang, E; Langen, K E; Anderson, K

    2012-02-01

    We conducted a randomised controlled trial comparing the laryngeal mask airway Supreme(™) with the laryngeal mask airway Unique(™) in children. Fifty children presenting for elective surgery were randomly assigned to receive either the laryngeal mask airway Supreme or laryngeal mask airway Unique. The outcomes measured were airway leak pressure, ease and time for insertion, insertion success rate, fibreoptic examination, incidence of gastric insufflation, ease of gastric tube placement through the laryngeal mask airway Supreme, quality of airway during anaesthetic maintenance and complications. Median (IQR [range]) time to successful device placement was shorter with the laryngeal mask airway Unique, 14.5 [13.5-16.3 (10.0-23.6)] s than with the laryngeal mask airway Supreme, 17.4 [14.8-19.8 (11.5-29.2)] s; p = 0.007. Median (IQR [range]) airway leak pressures for the laryngeal mask airway Supreme and laryngeal mask airway Unique were 20 [16-21 (12-22)] cmH(2)O and 15 [14-18 (10-24)] cmH(2)O, respectively (p = 0.001). The incidence of gastric insufflation was lower with the laryngeal mask airway Supreme (zero vs six patients), p = 0.01. In conclusion, the laryngeal mask airway Supreme performed as well as the laryngeal mask airway Unique and is a useful alternative for airway maintenance, particularly in children who require evacuation of gastric contents during anaesthesia. Anaesthesia © 2011 The Association of Anaesthetists of Great Britain and Ireland.

  19. Nerve fascicle transfer using a part of the C-7 nerve for spinal accessory nerve injury.

    Science.gov (United States)

    Ye, Xuan; Shen, Yun-Dong; Feng, Jun-Tao; Xu, Wen-Dong

    2018-02-09

    OBJECTIVE Spinal accessory nerve (SAN) injury results in a series of shoulder dysfunctions and continuous pain. However, current treatments are limited by the lack of donor nerves as well as by undesirable nerve regeneration. Here, the authors report a modified nerve transfer technique in which they employ a nerve fascicle from the posterior division (PD) of the ipsilateral C-7 nerve to repair SAN injury. The technique, first performed in cadavers, was then undertaken in 2 patients. METHODS Six fresh cadavers (12 sides of the SAN and ipsilateral C-7) were studied to observe the anatomical relationship between the SAN and C-7 nerve. The length from artificial bifurcation of the middle trunk to the point of the posterior cord formation in the PD (namely, donor nerve fascicle) and the linear distance from the cut end of the donor fascicle to both sites of the jugular foramen and medial border of the trapezius muscle (d-SCM and d-Traps, respectively) were measured. Meanwhile, an optimal route for nerve fascicle transfer (NFT) was designed. The authors then performed successful NFT operations in 2 patients, one with an injury at the proximal SAN and another with an injury at the distal SAN. RESULTS The mean lengths of the cadaver donor nerve fascicle, d-SCM, and d-Traps were 4.2, 5.2, and 2.5 cm, respectively. In one patient who underwent proximal SAN excision necessitated by a partial thyroidectomy, early signs of reinnervation were seen on electrophysiological testing at 6 months after surgery, and an impaired left trapezius muscle, which was completely atrophic preoperatively, had visible signs of improvement (from grade M0 to grade M3 strength). In the other patient in whom a distal SAN injury was the result of a neck cyst resection, reinnervation and complex repetitive discharges were seen 1 year after surgery. Additionally, the patient's denervated trapezius muscle was completely resolved (from grade M2 to grade M4 strength), and her shoulder pain had disappeared

  20. The Role of Nerve Exploration in Supracondylar Humerus Fracture in Children with Nerve Injury

    Directory of Open Access Journals (Sweden)

    Anuar RIM

    2015-11-01

    Full Text Available The supracondylar humerus fracture (SCHF in children is common and can be complicated with nerve injury either primarily immediate post-trauma or secondarily posttreatment. The concept of neurapraxic nerve injury makes most surgeons choose to ‘watch and see’ the nerve recovery before deciding second surgery if the nerve does not recover. We report three cases of nerve injury in SCHF, all of which underwent nerve exploration for different reasons. Early reduction in the Casualty is important to release the nerve tension before transferring the patient to the operation room. If close reduction fails, we proceed to explore the nerve together with open reduction of the fracture. In iatrogenic nerve injury, we recommend nerve exploration to determine the surgical procedure that is causing the injury. Primary nerve exploration will allow early assessment of the injured nerve and minimize subsequent surgery.