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Sample records for nerve block role

  1. Ischemic Nerve Block.

    ERIC Educational Resources Information Center

    Williams, Ian D.

    This experiment investigated the capability for movement and muscle spindle function at successive stages during the development of ischemic nerve block (INB) by pressure cuff. Two male subjects were observed under six randomly ordered conditions. The duration of index finger oscillation to exhaustion, paced at 1.2Hz., was observed on separate…

  2. The Role of Selective Nerve Root Block in the Treatment of Lumbar Radicular Leg Pain.

    PubMed

    Jonayed, S A; Kamruzzaman, M; Saha, M K; Alam, S; Akter, S

    2016-01-01

    The objective of this retrospective study was to investigate the clinical effectiveness of nerve root blocks (i.e., periradicular injection of Lidocaine and triamcinolone) for lumbar monoradiculopathy in patients with a mild neurological deficit in National Institute of Traumatology & Orthopaedic Rehabilitation (NITOR), Dhaka, Bangladesh from March 2014 to December 2014. We Included 24 patients (32-74 years) with a minor sensory/motor deficit and an unequivocal MRI finding (18 disc herniations, 6 foraminal stenosis) treated with a selective nerve root block. Based on the clinical and imaging findings, surgery (decompression of the nerve root) was justifiable in all cases. Seventeen patients (87%) had rapid (1-4 days) and substantial regression of pain, four required a repeat injection. Sixty percent (60%) of the patients with disc herniation or foraminal stenosis had permanent resolution of pain, so that an operation was avoided over an average of 6 months (2-9 months) follow-up. Nerve root blocks are very effective in the non-operative treatment of minor monoradiculopathy and should be recommended as the initial treatment of choice for this condition. PMID:26931264

  3. The Role of Selective Nerve Root Block in the Treatment of Lumbar Radicular Leg Pain.

    PubMed

    Jonayed, S A; Kamruzzaman, M; Saha, M K; Alam, S; Akter, S

    2016-01-01

    The objective of this retrospective study was to investigate the clinical effectiveness of nerve root blocks (i.e., periradicular injection of Lidocaine and triamcinolone) for lumbar monoradiculopathy in patients with a mild neurological deficit in National Institute of Traumatology & Orthopaedic Rehabilitation (NITOR), Dhaka, Bangladesh from March 2014 to December 2014. We Included 24 patients (32-74 years) with a minor sensory/motor deficit and an unequivocal MRI finding (18 disc herniations, 6 foraminal stenosis) treated with a selective nerve root block. Based on the clinical and imaging findings, surgery (decompression of the nerve root) was justifiable in all cases. Seventeen patients (87%) had rapid (1-4 days) and substantial regression of pain, four required a repeat injection. Sixty percent (60%) of the patients with disc herniation or foraminal stenosis had permanent resolution of pain, so that an operation was avoided over an average of 6 months (2-9 months) follow-up. Nerve root blocks are very effective in the non-operative treatment of minor monoradiculopathy and should be recommended as the initial treatment of choice for this condition.

  4. Peripheral nerve blocks for distal extremity surgery.

    PubMed

    Offierski, Chris

    2013-10-01

    Peripheral nerve block is well suited for distal extremity surgery. Blocking the nerves at the distal extremity is easily done. It does not require ultrasound or stimulators to identify the nerve. Blocking nerves in the distal extremity is safe with low risk of toxicity. The effect of the nerve block is limited to the distribution of the nerve. The distal nerves in the lower extremity are sensory branches of the sciatic nerve. This provides a sensory block only. This has the advantage of allowing the patient to actively contract tendons in the foot and ambulate more quickly after surgery. PMID:24093651

  5. Arthroscopic medial meniscus trimming or repair under nerve blocks: Which nerves should be blocked?

    PubMed Central

    Taha, AM; Abd-Elmaksoud, AM

    2016-01-01

    Background: This study aimed to determine the role of the sciatic and obturator nerve blocks (in addition to femoral block) in providing painless arthroscopic medial meniscus trimming/repair. Materials and Methods: One hundred and twenty patients with medial meniscus tear, who had been scheduled to knee arthroscopy, were planned to be included in this controlled prospective double-blind study. The patients were randomly allocated into three equal groups; FSO, FS, and FO. The femoral, sciatic, and obturator nerves were blocked in FSO groups. The femoral and sciatic nerves were blocked in FS group, while the femoral and obturator nerves were blocked in FO group. Intraoperative pain and its causative surgical maneuver were recorded. Results: All the patients (n = 7, 100%) in FO group had intraoperative pain. The research was terminated in this group but completed in FS and FSO groups (40 patients each). During valgus positioning of the knee for surgical management of the medial meniscus tear, the patients in FS group experienced pain more frequently than those in FSO group (P = 0.005). Conclusion: Adding a sciatic nerve block to the femoral nerve block is important for painless knee arthroscopy. Further adding of an obturator nerve block may be needed when a valgus knee position is required to manage the medial meniscus tear. PMID:27375382

  6. [Electrical nerve stimulation for plexus and nerve blocks].

    PubMed

    Birnbaum, J; Klotz, E; Bogusch, G; Volk, T

    2007-11-01

    Despite the increasing use of ultrasound, electrical nerve stimulation is commonly used as the standard for both plexus and peripheral nerve blocks. Several recent randomized trials have contributed to a better understanding of physiological and clinical correlations. Traditionally used currents and impulse widths are better defined in relation to the distance between needle tip and nerves. Commercially available devices enable transcutaneous nerve stimulation and provide new opportunities for the detection of puncture sites and for training. The electrically ideal position of the needle usually is defined by motor responses which can not be interpreted without profound anatomical knowledge. For instance, interscalene blocks can be successful even after motor responses of deltoid or pectoral muscles. Infraclavicular blocks should be aimed at stimulation of the posterior fascicle (extension). In contrast to multiple single nerve blocks, axillary single-shot blocks more commonly result in incomplete anaesthesia. Blockade of the femoral nerve can be performed without any nerve stimulation if the fascia iliaca block is used. Independently of the various approaches to the sciatic nerve, inversion and plantar flexion are the best options for single-shot blocks. Further clinical trials are needed to define the advantages of stimulating catheters in continuous nerve blocks.

  7. Inferior alveolar nerve block: Alternative technique

    PubMed Central

    Thangavelu, K.; Kannan, R.; Kumar, N. Senthil

    2012-01-01

    Background: Inferior alveolar nerve block (IANB) is a technique of dental anesthesia, used to produce anesthesia of the mandibular teeth, gingivae of the mandible and lower lip. The conventional IANB is the most commonly used the nerve block technique for achieving local anesthesia for mandibular surgical procedures. In certain cases, however, this nerve block fails, even when performed by the most experienced clinician. Therefore, it would be advantageous to find an alternative simple technique. Aim and Objective: The objective of this study is to find an alternative inferior alveolar nerve block that has a higher success rate than other routine techniques. To this purpose, a simple painless inferior alveolar nerve block was designed to anesthetize the inferior alveolar nerve. Materials and Methods: This study was conducted in Oral surgery department of Vinayaka Mission's dental college Salem from May 2009 to May 2011. Five hundred patients between the age of 20 years and 65 years who required extraction of teeth in mandible were included in the study. Out of 500 patients 270 were males and 230 were females. The effectiveness of the IANB was evaluated by using a sharp dental explorer in the regions innervated by the inferior alveolar, lingual, and buccal nerves after 3, 5, and 7 min, respectively. Conclusion: This study concludes that inferior alveolar nerve block is an appropriate alternative nerve block to anesthetize inferior alveolar nerve due to its several advantages. PMID:25885503

  8. Perioperative pain control after total knee arthroplasty: An evidence based review of the role of peripheral nerve blocks

    PubMed Central

    Danninger, Thomas; Opperer, Mathias; Memtsoudis, Stavros G

    2014-01-01

    Over the last decades, the number of total knee arthroplasty procedures performed in the United States has been increasing dramatically. This very successful intervention, however, is associated with significant postoperative pain, and adequate postoperative analgesia is mandatory in order to allow for successful rehabilitation and recovery. The use of regional anesthesia and peripheral nerve blocks has facilitated and improved this goal. Many different approaches and techniques for peripheral nerve blockades, either landmark or, more recently, ultrasound guided have been described over the last decades. This includes but is not restricted to techniques discussed in this review. The introduction of ultrasound has improved many approaches to peripheral nerves either in success rate and/or time to block. Moreover, ultrasound has enhanced the safety of peripheral nerve blocks due to immediate needle visualization and as consequence needle guidance during the block. In contrast to patient controlled analgesia using opioids, patients with a regional anesthetic technique suffer from fewer adverse events and show higher patient satisfaction; this is important as hospital rankings and advertisement have become more common worldwide and many patients use these factors in order to choose a certain institution for a specific procedure. This review provides a short overview of currently used regional anesthetic and analgesic techniques focusing on related implications, considerations and outcomes. PMID:25035824

  9. [Obturator nerve block in transurethral surgery].

    PubMed

    Rubial Alvarez, M; Molins Gauna, N; Rubio Pascual, P; Martín Bermejo, P; Pamplona Casamayor, M

    1989-01-01

    The obturator nerve passes in close proximity to the bladder as it courses through the pelvis. During transurethral operations, resection may result in stimulation of the obturator nerve, causing violent adductor contraction. Bladder perforation and incomplete tumor resection are the most important complications. All techniques proposed since transurethral surgery began, until nowadays are reviewed: neuromuscular blockade, electric circuit modifications, transparietal endoscopic blockade, periprostatic and subvesical infiltration, obturator nerve blockade and the "3 in 1 block" described by Winnie. Practical advices are proposed finally.

  10. Neurologic complication after anterior sciatic nerve block.

    PubMed

    Shah, Shruti; Hadzic, Admir; Vloka, Jerry D; Cafferty, Maureen S; Moucha, Calin S; Santos, Alan C

    2005-05-01

    The lack of reported complications related to lower extremity peripheral nerve blocks (PNBs) may be related to the relatively infrequent application of these techniques and to the fact that most such events go unpublished. Our current understanding of the factors that lead to neurologic complications after PNBs is limited. This is partly the result of our inability to conduct meaningful retrospective studies because of a lack of standard and objective monitoring and documentation procedures for PNBs. We report a case of permanent injury to the sciatic nerve after sciatic nerve block through the anterior approach and discuss mechanisms that may have led to the injury. Intraneural injection and nerve injury can occur in the absence of pain on injection and it may be heralded by high injection pressure (resistance).

  11. Combined KHFAC + DC nerve block without onset or reduced nerve conductivity after block

    NASA Astrophysics Data System (ADS)

    Franke, Manfred; Vrabec, Tina; Wainright, Jesse; Bhadra, Niloy; Bhadra, Narendra; Kilgore, Kevin

    2014-10-01

    Objective. Kilohertz frequency alternating current (KHFAC) waveforms have been shown to provide peripheral nerve conductivity block in many acute and chronic animal models. KHFAC nerve block could be used to address multiple disorders caused by neural over-activity, including blocking pain and spasticity. However, one drawback of KHFAC block is a transient activation of nerve fibers during the initiation of the nerve block, called the onset response. The objective of this study is to evaluate the feasibility of using charge balanced direct current (CBDC) waveforms to temporarily block motor nerve conductivity distally to the KHFAC electrodes to mitigate the block onset-response. Approach. A total of eight animals were used in this study. A set of four animals were used to assess feasibility and reproducibility of a combined KHFAC + CBDC block. A following randomized study, conducted on a second set of four animals, compared the onset response resulting from KHFAC alone and combined KHFAC + CBDC waveforms. To quantify the onset, peak forces and the force-time integral were measured during KHFAC block initiation. Nerve conductivity was monitored throughout the study by comparing muscle twitch forces evoked by supra-maximal stimulation proximal and distal to the block electrodes. Each animal of the randomized study received at least 300 s (range: 318-1563 s) of cumulative dc to investigate the impact of combined KHFAC + CBDC on nerve viability. Main results. The peak onset force was reduced significantly from 20.73 N (range: 18.6-26.5 N) with KHFAC alone to 0.45 N (range: 0.2-0.7 N) with the combined CBDC and KHFAC block waveform (p < 0.001). The area under the force curve was reduced from 6.8 Ns (range: 3.5-21.9 Ns) to 0.54 Ns (range: 0.18-0.86 Ns) (p < 0.01). No change in nerve conductivity was observed after application of the combined KHFAC + CBDC block relative to KHFAC waveforms. Significance. The distal application of CBDC can significantly reduce or even

  12. Ultrasound guided nerve block for breast surgery.

    PubMed

    Diéguez, P; Casas, P; López, S; Fajardo, M

    2016-03-01

    The breast surgery has undergone changes in recent years, encouraging new initiatives for the anaesthetic management of these patients in order to achieve maximum quality and rapid recovery. The fundamental tool that has allowed a significant improvement in the progress of regional anaesthesia for breast disease has been ultrasound, boosting the description and introduction into clinical practice of interfascial chest wall blocks, although the reference standard is still the paravertebral block. It is very likely that these blocks will change the protocols in the coming years. A review is presented of the anatomy of the breast region, description of nerve blocks and techniques, as well as their indications, all according to published articles and the opinion of the authors based on their experience.

  13. Ultrasound guided nerve block for breast surgery.

    PubMed

    Diéguez, P; Casas, P; López, S; Fajardo, M

    2016-03-01

    The breast surgery has undergone changes in recent years, encouraging new initiatives for the anaesthetic management of these patients in order to achieve maximum quality and rapid recovery. The fundamental tool that has allowed a significant improvement in the progress of regional anaesthesia for breast disease has been ultrasound, boosting the description and introduction into clinical practice of interfascial chest wall blocks, although the reference standard is still the paravertebral block. It is very likely that these blocks will change the protocols in the coming years. A review is presented of the anatomy of the breast region, description of nerve blocks and techniques, as well as their indications, all according to published articles and the opinion of the authors based on their experience. PMID:26776926

  14. Physiological and pharmacologic aspects of peripheral nerve blocks

    PubMed Central

    Vadhanan, Prasanna; Tripaty, Debendra Kumar; Adinarayanan, S.

    2015-01-01

    A successful peripheral nerve block not only involves a proper technique, but also a thorough knowledge and understanding of the physiology of nerve conduction and pharmacology of local anesthetics (LAs). This article focuses on what happens after the block. Pharmacodynamics of LAs, underlying mechanisms of clinically observable phenomena such as differential blockade, tachyphylaxis, C fiber resistance, tonic and phasic blockade and effect of volume and concentration of LAs. Judicious use of additives along with LAs in peripheral nerve blocks can prolong analgesia. An entirely new group of drugs-neurotoxins has shown potential as local anesthetics. Various methods are available now to prolong the duration of peripheral nerve blocks. PMID:26330722

  15. Peripheral nerve blocks for ambulatory surgery.

    PubMed

    Salinas, Francis V; Joseph, Raymond S

    2014-06-01

    Peripheral nerve blocks (PNBs) provide significant improvement in postoperative analgesia and quality of recovery for ambulatory surgery. Use of continuous PNB techniques extend these benefits beyond the limited duration of single-injection PNBs. The use of ultrasound guidance has significantly improved the overall success, efficiency, and has contributed to the increased use of PNBs in the ambulatory setting. More recently, the use of ultrasound guidance has been demonstrated to decrease the risk of local anesthetic systemic toxicity. This article provides a broad overview of the indications and clinically useful aspects of the most commonly used upper and lower extremity PNBs in the ambulatory setting. Emphasis is placed on approaches that can be used for single-injection PNBs and continuous PNB techniques.

  16. Different clinical electrodes achieve similar electrical nerve conduction block

    NASA Astrophysics Data System (ADS)

    Boger, Adam; Bhadra, Narendra; Gustafson, Kenneth J.

    2013-10-01

    Objective. We aim to evaluate the suitability of four electrodes previously used in clinical experiments for peripheral nerve electrical block applications. Approach. We evaluated peripheral nerve electrical block using three such clinical nerve cuff electrodes (the Huntington helix, the Case self-sizing Spiral and the flat interface nerve electrode) and one clinical intramuscular electrode (the Memberg electrode) in five cats. Amplitude thresholds for the block using 12 or 25 kHz voltage-controlled stimulation, onset response, and stimulation thresholds before and after block testing were determined. Main results. Complete nerve block was achieved reliably and the onset response to blocking stimulation was similar for all electrodes. Amplitude thresholds for the block were lowest for the Case Spiral electrode (4 ± 1 Vpp) and lower for the nerve cuff electrodes (7 ± 3 Vpp) than for the intramuscular electrode (26 ± 10 Vpp). A minor elevation in stimulation threshold and reduction in stimulus-evoked urethral pressure was observed during testing, but the effect was temporary and did not vary between electrodes. Significance. Multiple clinical electrodes appear suitable for neuroprostheses using peripheral nerve electrical block. The freedom to choose electrodes based on secondary criteria such as ease of implantation or cost should ease translation of electrical nerve block to clinical practice.

  17. Lower limb surgeries under combined femoral and sciatic nerve block

    PubMed Central

    Bansal, Lipsy; Attri, Joginder Pal; Verma, Pawan

    2016-01-01

    Introduction: Peripheral nerve blocks are gaining popularity for many infraumblical surgeries with the development of new techniques such as ultrasound and peripheral nerve stimulator. It provides stable hemodynamic, better, and prolonged postoperative analgesia. This study was carried out to see the effectiveness of combined femoral and sciatic nerve block with ropivacaine alone and by adding fentanyl. Materials and Methods: The study was carried out on 100 patients scheduled for lower limb surgeries and were randomly divided into two groups of 50 each. In Group A, patients received 20 ml of 0.5% ropivacaine for femoral nerve block and same dose for sciatic nerve block and in Group B, 25 μg fentanyl was added each for femoral nerve and sciatic nerve block along with ropivacaine. All hemodynamic parameters, onset and duration of sensory and motor blocks were noted. The patient characteristics were analyzed using the “Chi-square tests” and the intergroup comparison of the parametric data was carried out using the unpaired t-test using software IBM SPSS 17.0. Results: Combined femoral and sciatic nerve block provide longer duration of postoperative analgesia of about 12–13 h. All the above-mentioned parameters were statistically non-significant. Conclusion: Hence in this study, onset and duration of sensory and motor block was comparable in both groups. However postoperative analgesia was prolonged as compared to neuraxial blockade without any hemodynamic instability. PMID:27746528

  18. Workflow in interventional radiology: nerve blocks and facet blocks

    NASA Astrophysics Data System (ADS)

    Siddoway, Donald; Ingeholm, Mary Lou; Burgert, Oliver; Neumuth, Thomas; Watson, Vance; Cleary, Kevin

    2006-03-01

    Workflow analysis has the potential to dramatically improve the efficiency and clinical outcomes of medical procedures. In this study, we recorded the workflow for nerve block and facet block procedures in the interventional radiology suite at Georgetown University Hospital in Washington, DC, USA. We employed a custom client/server software architecture developed by the Innovation Center for Computer Assisted Surgery (ICCAS) at the University of Leipzig, Germany. This software runs in an internet browser, and allows the user to record the actions taken by the physician during a procedure. The data recorded during the procedure is stored as an XML document, which can then be further processed. We have successfully gathered data on a number if cases using a tablet PC, and these preliminary results show the feasibility of using this software in an interventional radiology setting. We are currently accruing additional cases and when more data has been collected we will analyze the workflow of these procedures to look for inefficiencies and potential improvements.

  19. Continuous extrapleural intercostal nerve block after pleurectomy.

    PubMed Central

    Mozell, E. J.; Sabanathan, S.; Mearns, A. J.; Bickford-Smith, P. J.; Majid, M. R.; Zografos, G.

    1991-01-01

    A randomised, double blind trial was carried out in 16 patients undergoing pleurectomy to assess the effect of continuous extrapleural intercostal block on postoperative pain and pulmonary function. Subjective pain relief was assessed on a linear visual analogue scale. Pulmonary function was measured on the day before operation and daily for five days after surgery. Eight patients received bupivacaine and eight placebo (saline). The mean pain scores at 4, 8, 16, and 24 hours were 13.3, 8.5, 6.1, and 10 mm respectively in the bupivacaine group compared with 56.3, 41, 46.7, and 35 in the control group; in addition, the bupivacaine group required less papaveretum. Twenty four hours after surgery mean values of peak expiratory flow, forced expiratory volume in one second, and forced vital capacity were reduced to 82%, 76%, and 76% of preoperative control values in the bupivacaine group, and to 39%, 32%, and 36% in the control group. The speed of recovery of pulmonary function was superior in the bupivacaine group. There were no complications related to the infusion. Continuous extrapleural intercostal nerve blockade with bupivacaine provides safe and effective postoperative analgesia and improves respiratory mechanics after pleurectomy. PMID:1871692

  20. Workup and Management of Persistent Neuralgia following Nerve Block

    PubMed Central

    Weyker, Paul David; Webb, Christopher Allen-John; Pham, Thoha M.

    2016-01-01

    Neurological injuries following peripheral nerve blocks are a relatively rare yet potentially devastating complication depending on the type of lesion, affected extremity, and duration of symptoms. Medical management continues to be the treatment modality of choice with multimodal nonopioid analgesics as the cornerstone of this therapy. We report the case of a 28-year-old man who developed a clinical common peroneal and lateral sural cutaneous neuropathy following an uncomplicated popliteal sciatic nerve block. Workup with electrodiagnostic studies and magnetic resonance neurography revealed injury to both the femoral and sciatic nerves. Diagnostic studies and potential mechanisms for nerve injury are discussed. PMID:26904304

  1. Pediatric nerve blocks: an evidence-based approach.

    PubMed

    Duchicela, Sacha; Lim, Anthoney

    2013-10-01

    Successful injury management is often dependent upon optimal pain control. Many injuries do not require procedural sedation or systemic analgesia, and emergency clinicians have used peripheral nerve blocks for several decades for these injuries. Nerve blocks deliver anesthetic to the nerve that corresponds to the sensory innervation of the area where the wound or injury is located. In the pediatric setting, some nerve block modalities require modification to the approach and techniques commonly used in adult patients due to the age and weight of the child, the ability of the patient to cooperate, and the ability of the emergency clinician to observe pain response. Peripheral nerve blocks have a high rate of success for effective local anesthesia and a low rate of complications, making them an attractive option for analgesia in the management of some injuries. This evidence-based review summarizes the advantages and disadvantages of peripheral nerve blocks, reviews commonly used local anesthetics, describes the landmark technique for the most common nerve blocks used in pediatric emergency medicine, and presents literature on ultrasound-guided technology.

  2. [Anatomical rationale for lingual nerve injury prevention during mandibular block].

    PubMed

    Semkin, V A; Dydikin, S S; Kuzin, A V; Sogacheva, V V

    2015-01-01

    The topographic and anatomical study of lingual nerve structural features was done. It was revealed that during mandibular anesthesia possible lingual nerve injury can occur if puncture needle is lower than 1 cm. of molars occlusal surface level. The position of the lingual nerve varies withmandible movements. At the maximum open mouth lingual nerve is not mobile and is pressed against the inner surface of the mandibular ramus by the medial pterygoid muscle and the temporal muscle tendon. When closing the mouth to 1.25±0.2 cmfrom the physiological maximum, lingual nerve is displaced posteriorly from the internal oblique line of the mandible and gets mobile. On the basis of topographic and anatomic features of the lingual nervestructure the authors recommend the re-do of inferior alveolar nerve block, a semi-closed mouth position or the use the "high block techniques" (Torus anesthesia, Gow-Gates, Vazirani-Akinozi). PMID:26271698

  3. High frequency electrical conduction block of the pudendal nerve

    NASA Astrophysics Data System (ADS)

    Bhadra, Narendra; Bhadra, Niloy; Kilgore, Kevin; Gustafson, Kenneth J.

    2006-06-01

    A reversible electrical block of the pudendal nerves may provide a valuable method for restoration of urinary voiding in individuals with bladder-sphincter dyssynergia. This study quantified the stimulus parameters and effectiveness of high frequency (HFAC) sinusoidal waveforms on the pudendal nerves to produce block of the external urethral sphincter (EUS). A proximal electrode on the pudendal nerve after its exit from the sciatic notch was used to apply low frequency stimuli to evoke EUS contractions. HFAC at frequencies from 1 to 30 kHz with amplitudes from 1 to 10 V were applied through a conforming tripolar nerve cuff electrode implanted distally. Sphincter responses were recorded with a catheter mounted micro-transducer. A fast onset and reversible motor block was obtained over this range of frequencies. The HFAC block showed three phases: a high onset response, often a period of repetitive firing and usually a steady state of complete or partial block. A complete EUS block was obtained in all animals. The block thresholds showed a linear relationship with frequency. HFAC pudendal nerve stimulation effectively produced a quickly reversible block of evoked urethral sphincter contractions. The HFAC pudendal block could be a valuable tool in the rehabilitation of bladder-sphincter dyssynergia.

  4. A basic review on the inferior alveolar nerve block techniques

    PubMed Central

    Khalil, Hesham

    2014-01-01

    The inferior alveolar nerve block is the most common injection technique used in dentistry and many modifications of the conventional nerve block have been recently described in the literature. Selecting the best technique by the dentist or surgeon depends on many factors including the success rate and complications related to the selected technique. Dentists should be aware of the available current modifications of the inferior alveolar nerve block techniques in order to effectively choose between these modifications. Some operators may encounter difficulty in identifying the anatomical landmarks which are useful in applying the inferior alveolar nerve block and rely instead on assumptions as to where the needle should be positioned. Such assumptions can lead to failure and the failure rate of inferior alveolar nerve block has been reported to be 20-25% which is considered very high. In this basic review, the anatomical details of the inferior alveolar nerve will be given together with a description of its both conventional and modified blocking techniques; in addition, an overview of the complications which may result from the application of this important technique will be mentioned. PMID:25886095

  5. Reversible Nerve Conduction Block Using Kilohertz Frequency Alternating Current

    PubMed Central

    Kilgore, Kevin L.; Bhadra, Niloy

    2013-01-01

    Objectives The features and clinical applications of balanced-charge kilohertz frequency alternating currents (KHFAC) are reviewed. Preclinical studies of KHFAC block have demonstrated that it can produce an extremely rapid and reversible block of nerve conduction. Recent systematic analysis and experimentation utilizing KHFAC block has resulted in a significant increase in interest in KHFAC block, both scientifically and clinically. Materials and Methods We review the history and characteristics of KHFAC block, the methods used to investigate this type of block, the experimental evaluation of block, and the electrical parameters and electrode designs needed to achieve successful block. We then analyze the existing clinical applications of high frequency currents, comparing the early results with the known features of KHFAC block. Results Although many features of KHFAC block have been characterized, there is still much that is unknown regarding the response of neural structures to rapidly fluctuating electrical fields. The clinical reports to date do not provide sufficient information to properly evaluate the mechanisms that result in successful or unsuccessful treatment. Conclusions KHFAC nerve block has significant potential as a means of controlling nerve activity for the purpose of treating disease. However, early clinical studies in the use of high frequency currents for the treatment of pain have not been designed to elucidate mechanisms or allow direct comparisons to preclinical data. We strongly encourage the careful reporting of the parameters utilized in these clinical studies, as well as the development of outcome measures that could illuminate the mechanisms of this modality. PMID:23924075

  6. Differential fiber-specific block of nerve conduction in mammalian peripheral nerves using kilohertz electrical stimulation

    PubMed Central

    Patel, Yogi A.

    2015-01-01

    Kilohertz electrical stimulation (KES) has been shown to induce repeatable and reversible nerve conduction block in animal models. In this study, we characterized the ability of KES stimuli to selectively block specific components of stimulated nerve activity using in vivo preparations of the rat sciatic and vagus nerves. KES stimuli in the frequency range of 5–70 kHz and amplitudes of 0.1–3.0 mA were applied. Compound action potentials were evoked using either electrical or sensory stimulation, and block of components was assessed through direct nerve recordings and muscle force measurements. Distinct observable components of the compound action potential had unique conduction block thresholds as a function of frequency of KES. The fast component, which includes motor activity, had a monotonically increasing block threshold as a function of the KES frequency. The slow component, which includes sensory activity, showed a nonmonotonic block threshold relationship with increasing KES frequency. The distinct trends with frequency of the two components enabled selective block of one component with an appropriate choice of frequency and amplitude. These trends in threshold of the two components were similar when studying electrical stimulation and responses of the sciatic nerve, electrical stimulation and responses of the vagus nerve, and sensorimotor stimulation and responses of the sciatic nerve. This differential blocking effect of KES on specific fibers can extend the applications of KES conduction block to selective block and stimulation of neural signals for neuromodulation as well as selective control of neural circuits underlying sensorimotor function. PMID:25878155

  7. Ultrasound-Guided Musculocutaneous Nerve Block in Postherpetic Neuralgia.

    PubMed

    Kuo, Ying-Chen; Hsieh, Lin-Fen; Chiou, Hong-Jen

    2016-01-01

    Postherpetic neuralgia is a common and challenging complication of herpes zoster infection, particularly in older people. In recent decades, first-line treatments, including oral or topical medication, have become well established. However, few studies have reported the efficacy of interventional procedures for the treatment of postherpetic neuralgia. Here, the authors present a case of intractable postherpetic neuralgia treated with musculocutaneous peripheral nerve block under ultrasound guidance. Symptoms remained controlled at 1 mo follow-up. Ultrasound can be readily applied to improve the accuracy and efficiency of peripheral nerve block as it is currently widely used to evaluate the musculoskeletal system in clinical settings.

  8. Humeral head translation after a suprascapular nerve block.

    PubMed

    San Juan, Jun G; Kosek, Peter; Karduna, Andrew R

    2013-08-01

    Subacromial impingement syndrome is the most common shoulder disorder. Abnormal superior translation of the humeral head is believed to be a major cause of this pathology. The first purpose of the study was to examine the effects of suprascapular nerve block on superior translation of the humeral head and scapular upward rotation during dynamic shoulder elevation. The secondary purpose was to assess muscle activation patterns during these motions. Twenty healthy subjects participated in the study. Using fluoroscopy and electromyography, humeral head translation and muscle activation were measured before and after a suprascapular nerve block. The humeral head was superiorly located at 60 degrees of humeral elevation, and the scapula was more upwardly rotated from 30 to 90 degrees of humeral elevation after the block. The differences were observed during midrange of motion. In addition, the deltoid muscle group demonstrated increased muscle activation after the nerve block. The study's results showed a compensatory increase in humeral head translation, scapular upward rotation, and deltoid muscle activation due to the nerve block. These outcomes suggest that increasing muscular strength and endurance of the supraspinatus and infraspinatus muscles could prevent any increased superior humeral head translation. This may be beneficial in reducing shoulder impingement or rotator cuff tears over time. PMID:22927503

  9. Symptomatic phrenic nerve palsy after supraclavicular block in an obese man.

    PubMed

    Erickson, John M; Louis, Dean S; Naughton, Norah N

    2009-05-01

    Regional anesthesia has an expanding role in upper extremity surgery. Brachial plexus blocks offer several advantages including providing effective analgesia, reducing narcotic requirements, and facilitating ambulatory care surgery. Despite the popularity of nerve blocks, the surgeon must not forget the complications associated with regional anesthesia. This article describes a case of symptomatic phrenic nerve palsy after supraclavicular brachial plexus block in an obese man. A 46-year-old obese man underwent a left-sided supraclavicular block in preparation for decompression of Guyon's canal for ulnar mononeuropathy at the wrist. The patient experienced acute-onset dyspnea, chest discomfort, and anxiety, and physical examination demonstrated reduced breath sounds in the left hemithorax. Chest radiographs documented elevation of the left hemidiaphragm consistent with an iatrogenic phrenic nerve palsy. The patient was admitted for 23-hour observation and underwent an uncomplicated ulnar nerve decompression under Bier block anesthesia 1 week later. No long-term sequelae have been identified; however, there was a delay in surgical care, admission to the hospital, and transient pulmonary symptoms. We attribute this complication to significant abdominal obesity causing compromised pulmonary reserve and poor tolerance of transient hemidiaphragmatic paresis. In recent studies, waist circumference and abdominal height were inversely related to pulmonary function. We suspect that the incidence of symptomatic phrenic nerve palsy associated with brachial plexus blocks will increase as the prevalence of obesity increases in this country. PMID:19472948

  10. High Frequency Sacral Root Nerve Block Allows Bladder Voiding

    PubMed Central

    Boger, Adam S.; Bhadra, Narendra; Gustafson, Kenneth J

    2013-01-01

    1) Aims Dyssynergic reflexive external urethral sphincter (EUS) activity following spinal cord injury can prevent bladder voiding, resulting in significant medical complications. Irreversible sphincterotomies or neurotomies can prevent EUS activation and allow bladder voiding, but may cause incontinence or loss of sacral reflexes. We investigated whether kilohertz frequency (KF) electrical conduction block of the sacral roots could prevent EUS activation and allow bladder voiding. 2) Methods The S2 sacral nerve roots were stimulated bilaterally to generate bladder pressure in 6 cats. One S1 nerve root was stimulated proximally (20 Hz biphasic pulse trains) to evoke EUS pressure, simulating worst-case dyssynergic EUS reflexes. KF waveforms (12.5 kHz biphasic square wave) applied to an electrode implanted distally on the S1 nerve root blocked nerve conduction, preventing the increase in EUS pressure and allowing voiding. 3) Results Applying KF waveforms increased bladder voiding in single, limited-duration trials from 3 ± 6% to 59 ± 12%. Voiding could be increased to 82 ± 9% of the initial bladder volume by repeating or increasing the duration of the trials. 4) Conclusions Sacral nerve block can prevent EUS activation and allow complete bladder voiding, potentially eliminating the need for a neurotomy. Eliminating neurotomy requirements could increase patient acceptance of bladder voiding neuroprostheses, increasing patient quality of life and reducing the cost of patient care. PMID:22473837

  11. Simple and safe posterior superior alveolar nerve block

    PubMed Central

    Thangavelu, K.; Kumar, N. Senthil; Kannan, R.; Kumar, J. Arun

    2012-01-01

    Background: The posterior superior alveolar nerve (PSAN) block is a dental nerve block used for profound anesthesia of the maxillary molars. Although it is being written in texts as a commonly used technique, but in dentistry it is rarely followed due to its nonreliable landmarks, variation in depth of insertion and frequent complications. The aim and objective are to find a technically simple method of the PSAN block without any complications. Study and Design: This study was based on the experience gained from 200 patients of 125 males and 75 female in age group of 20 to 65 years in University of Vinayaka and department of oral and maxillofacial surgery of VMS Dental College and hospital, Salem, Tamil Nadu. Results: In 200 patients’ positive anesthesia obtained within a period of 5 to 10 min. No visual complications reported in this study. There was no pain during and after extraction. Conclusion: This study shows this PSA nerve block using curved needle would avoid all complications reported in the literature. Therefore, the technique described in this study is an ideal option to anesthetize PSA nerve. PMID:25885507

  12. Molecular mechanisms of nerve block by local anesthetics.

    PubMed

    Strichartz, G

    1976-10-01

    Local anesthetics block nerve conduction by preventing the increase in membrane permeability to sodium ions that normally leads to a nerve impulse. Among anesthetics containing tertiary amine groups, the cationic, protonated form appears to be more active than the neutral form. However, the neutral forms, as well as uncharged molecules like benzocaine and the aliphatic alcohols, also depress sodium permeability. Studies of single myelinated nerves and squid axons show no direct interaction between calcium ions and local anesthetics, thus disproving theories based on competition between these two agents. Likewise, hypotheses attributing local anesthesia to changes in electrical potentials at the membrane-water interface are disproven by the demonstrated potencies of electrically uncharged anesthetics. Hypotheses that propose that local anesthetics act by expanding the nerve membrane and causing a change in protein conformation that blocks sodium permeability are vague in conception and difficult to test experimentally. Evidence from voltage-clamp studies of single nerve fibers indicates that anesthetic molecules interact with the sodium channels directly, from the inner side of the nerve membrane. Anesthetics bind within sodium channels which have opened during membrane depolarization, preventing the normal sodium ion flux. Anesthetic molecules can dissociate from open channels, but not from channels that remain closed when the nerve is kept at rest. The "gating" properties that regulate the opening and closing of sodium channels are reversibly modified during anesthesia. Specifically, the inactivation function responds more slowly and requires more negative membrane potential changes to reach the same values as in unanesthetized nerves. A second, slow inactivation is observed following external application of tertiary amine anesthetics. The selective binding of anesthetics to open sodium channels provides a simple explanation for Wedenski inhibition, in which the

  13. Simulation of spinal nerve blocks for training anesthesiology residents

    NASA Astrophysics Data System (ADS)

    Blezek, Daniel J.; Robb, Richard A.; Camp, Jon J.; Nauss, Lee A.; Martin, David P.

    1998-06-01

    Deep nerve regional anesthesiology procedures, such as the celiac plexus block, are challenging to learn. The current training process primarily involves studying anatomy and practicing needle insertion is cadavers. Unfortunately, the training often continues on the first few patients subjected to the care of the new resident. To augment the training, we have developed a virtual reality surgical simulation designed to provide an immersive environment in which an understanding of the complex 3D relationships among the anatomic structures involved can be obtained and the mechanics of the celiac block procedure practiced under realistic conditions. Study of the relevant anatomy is provided by interactive 3D visualization of patient specific data nd the practice simulated using a head mounted display, a 6 degree of freedom tracker, and a haptic feedback device simulating the needle insertion. By training in a controlled environment, the resident may practice procedures repeatedly without the risks associated with actual patient procedures, and may become more adept and confident in the ability to perform nerve blocks. The resident may select a variety of different nerve block procedures to practice, and may place the virtual patient in any desired position and orientation. The preliminary anatomic models used in the simulation have been computed from the Visible Human Male; however, patient specific models may be generated from patient image data, allowing the physician to evaluate, plan, and practice difficult blocks and/or understand variations in anatomy before attempting the procedure on any specific patient.

  14. Comparative analysis between direct Conventional Mandibular nerve block and Vazirani-Akinosi closed mouth Mandibular nerve block technique

    NASA Astrophysics Data System (ADS)

    Mishra, Sobhan; Tripathy, Ramanupam; Sabhlok, Samrat; Panda, Pankaj Kumar; Patnaik, Satyabrata

    2012-11-01

    Introduction: Over the years different techniques have been developed for achieving mandibular nerve anaesthesia. The main aim of our study was to carry out comparison and clinical efficacy of mandibular nerve anaesthesia by Direct Conventional technique with that of Vazirani-Akinosi mandibular nerve block technique.Materials and Methods: 50 adult patients requiring surgical extraction of premolars, mandibular first, second and third molars were selected randomly to receive Direct Conventional technique and Vazirani- Akinosi technique for nerve block alternatively.Results: No statistically significant differences were observed regarding complete lip anaesthesia at 5 minutes and 10 minutes, nerves anaesthetized with single injection, effectiveness of anaesthesia, supplementary injections and complications in both the techniques. However, onset of lip anaesthesia was found to be faster in Vazirani-Akinosi technique, patients experienced less pain during the Vazirani-Akinosi technique as compared to the Direct Conventional technique. Post injection complication complications were less in the VaziraniAkinosi Technique.Conclusions: Except for faster onset of lip anaesthesia, less pain during injection and fewer post injection complications in Vazirani-Akinosi technique all other parameters were of same efficacy as Direct Conventional technique. This has strong clinical applications as in cases with limited mouth opening, apprehensive patients Vazirani-Akinosi technique is the indicated technique of choice.

  15. Modeling Electric Fields of Peripheral Nerve Block Needles.

    NASA Astrophysics Data System (ADS)

    Davis, James Ch.; Anderson, Norman E.; Meisel, Mark W.; Ramirez, Jason G.; Kayser Enneking, F.

    2006-03-01

    Peripheral nerve blocks present an alternative to general anesthesia in certain surgical procedures and a means of acute pain relief through continuous blockades. They have been shown to decrease the incidence of postoperative nausea and vomiting, reduce oral narcotic side effects, and improve sleep quality. Injecting needles, which carry small stimulating currents, are often used to aid in locating the target nerve bundle. With this technique, muscle responses indicate needle proximity to the corresponding nerve bundle. Failure rates in first injection attempts prompted our study of electric field distributions. Finite difference methods were used to solve for the electric fields generated by two widely used needles. Geometric differences in the needles effect variations in their electric field and current distributions. Further investigations may suggest needle modifications that result in a reduction of initial probing failures.

  16. Modeling Electric Fields of Peripheral Nerve Block Needles.

    NASA Astrophysics Data System (ADS)

    Davis, James Ch.; Ramirez, Jason G.

    2005-11-01

    Peripheral nerve blocks present an alternative to general anesthesia in certain surgical procedures and a means of acute pain relief through continuous blockades. They have been shown to decrease the incidence of postoperative nausea and vomiting, reduce oral narcotic side effects, and improve sleep quality. Injecting needles, which carry small stimulating currents, are often used to aid in locating the target nerve bundle. With this technique, muscle responses indicate needle proximity to the corresponding nerve bundle. Failure rates in first injection attempts prompted our study of electric field distributions. Finite difference methods were used to solve for the electric fields generated by two widely used needles. Differences in geometry between needles are seen to effect changes in electric field and current distributions. Further investigations may suggest needle modifications that result in a reduction of initial probing failures.

  17. Nerve Conduction Block Using Combined Thermoelectric Cooling and High Frequency Electrical Stimulation

    PubMed Central

    Ackermann, D. Michael; Foldes, Emily L.; Bhadra, Niloy; Kilgore, Kevin L.

    2010-01-01

    Conduction block of peripheral nerves is an important technique for many basic and applied neurophysiology studies. To date, there has not been a technique which provides a quickly initiated and reversible “on-demand” conduction block which is both sustainable for long periods of time and does not generate activity in the nerve at the onset of the conduction block. In this study we evaluated the feasibility of a combined method of nerve block which utilizes two well established nerve blocking techniques in a rat and cat model: nerve cooling and electrical block using high frequency alternating currents (HFAC). This combined method effectively makes use of the contrasting features of both nerve cooling and electrical block using HFAC. The conduction block was initiated using nerve cooling, a technique which does not produce nerve “onset response” firing, a prohibitive drawback of HFAC electrical block. The conduction block was then readily transitioned into an electrical block. A long-term electrical block is likely preferential to a long-term nerve cooling block because nerve cooling block generates large amounts of exhaust heat, does not allow for fiber diameter selectivity and is known to be unsafe for prolonged delivery. PMID:20705099

  18. Nerve conduction block using combined thermoelectric cooling and high frequency electrical stimulation.

    PubMed

    Ackermann, D Michael; Foldes, Emily L; Bhadra, Niloy; Kilgore, Kevin L

    2010-10-30

    Conduction block of peripheral nerves is an important technique for many basic and applied neurophysiology studies. To date, there has not been a technique which provides a quickly initiated and reversible "on-demand" conduction block which is both sustainable for long periods of time and does not generate activity in the nerve at the onset of the conduction block. In this study we evaluated the feasibility of a combined method of nerve block which utilizes two well established nerve blocking techniques in a rat and cat model: nerve cooling and electrical block using high frequency alternating currents (HFAC). This combined method effectively makes use of the contrasting features of both nerve cooling and electrical block using HFAC. The conduction block was initiated using nerve cooling, a technique which does not produce nerve "onset response" firing, a prohibitive drawback of HFAC electrical block. The conduction block was then readily transitioned into an electrical block. A long-term electrical block is likely preferential to a long-term nerve cooling block because nerve cooling block generates large amounts of exhaust heat, does not allow for fiber diameter selectivity and is known to be unsafe for prolonged delivery.

  19. Femoral nerve block for patient undergoing total knee arthroplasty

    PubMed Central

    Heo, Bong Ha; Lee, Hyeon Jung; Lee, Hyung Gon; Kim, Man Young; Park, Keun Suk; Choi, Jeong Il; Yoon, Myung Ha; Kim, Woong Mo

    2016-01-01

    Abstract Background: The existence of peripheral opioid receptors and its effectiveness in peripheral nerve block remain controversial. The aim of this prospective, randomized, double-blinded study was to examine the analgesic effects of adding fentanyl to ropivacaine for continuous femoral nerve block (CFNB) using patient-controlled analgesia after total knee arthroplasty (TKA). Methods: The patients were divided into 2 groups, each with n = 40 in ropivacaine (R) group and n = 42 in R with fentanyl (R + F) group. After operation, the patients in each group received R + F and R alone via a femoral nerve catheter, respectively. We assessed the visual analog scale (VAS) pain immediately before administration (baseline) and at 15, 30, and 60 minutes on postanesthesia care unit (PACU), and resting and ambulatory VAS score up to 24 hours. Results: Overall, the average VAS scores in the R + F group were slightly lower than those of the R group. However, the VAS score differences between groups were not statistically significant, except for 30 minutes (P = 0.009) in PACU. R group showed higher supplemental analgesics consumption in average compared with R + F group, but not significant. Conclusion: Additional fentanyl did not show prominent enhancement of analgesic effect in the field of CFNB after TKA. PMID:27603376

  20. Anesthetic technique for inferior alveolar nerve block: a new approach

    PubMed Central

    PALTI, Dafna Geller; de ALMEIDA, Cristiane Machado; RODRIGUES, Antonio de Castro; ANDREO, Jesus Carlos; LIMA, José Eduardo Oliveira

    2011-01-01

    Background Effective pain control in Dentistry may be achieved by local anesthetic techniques. The success of the anesthetic technique in mandibular structures depends on the proximity of the needle tip to the mandibular foramen at the moment of anesthetic injection into the pterygomandibular region. Two techniques are available to reach the inferior alveolar nerve where it enters the mandibular canal, namely indirect and direct; these techniques differ in the number of movements required. Data demonstrate that the indirect technique is considered ineffective in 15% of cases and the direct technique in 1329% of cases. Objective Objective: The aim of this study was to describe an alternative technique for inferior alveolar nerve block using several anatomical points for reference, simplifying the procedure and enabling greater success and a more rapid learning curve. Materials and Methods A total of 193 mandibles (146 with permanent dentition and 47 with primary dentition) from dry skulls were used to establish a relationship between the teeth and the mandibular foramen. By using two wires, the first passing through the mesiobuccal groove and middle point of the mesial slope of the distolingual cusp of the primary second molar or permanent first molar (right side), and the second following the oclusal plane (left side), a line can be achieved whose projection coincides with the left mandibular foramen. Results The obtained data showed correlation in 82.88% of cases using the permanent first molar, and in 93.62% of cases using the primary second molar. Conclusion This method is potentially effective for inferior alveolar nerve block, especially in Pediatric Dentistry. PMID:21437463

  1. Augmented reality guidance system for peripheral nerve blocks

    NASA Astrophysics Data System (ADS)

    Wedlake, Chris; Moore, John; Rachinsky, Maxim; Bainbridge, Daniel; Wiles, Andrew D.; Peters, Terry M.

    2010-02-01

    Peripheral nerve block treatments are ubiquitous in hospitals and pain clinics worldwide. State of the art techniques use ultrasound (US) guidance and/or electrical stimulation to verify needle tip location. However, problems such as needle-US beam alignment, poor echogenicity of block needles and US beam thickness can make it difficult for the anesthetist to know the exact needle tip location. Inaccurate therapy delivery raises obvious safety and efficacy issues. We have developed and evaluated a needle guidance system that makes use of a magnetic tracking system (MTS) to provide an augmented reality (AR) guidance platform to accurately localize the needle tip as well as its projected trajectory. Five anesthetists and five novices performed simulated nerve block deliveries in a polyvinyl alcohol phantom to compare needle guidance under US alone to US placed in our AR environment. Our phantom study demonstrated a decrease in targeting attempts, decrease in contacting of critical structures, and an increase in accuracy of 0.68 mm compared to 1.34mm RMS in US guidance alone. Currently, the MTS uses 18 and 21 gauge hypodermic needles with a 5 degree of freedom sensor located at the needle tip. These needles can only be sterilized using an ethylene oxide process. In the interest of providing clinicians with a simple and efficient guidance system, we also evaluated attaching the sensor at the needle hub as a simple clip-on device. To do this, we simultaneously performed a needle bending study to assess the reliability of a hub-based sensor.

  2. Postoperative Outcome Comparison Between Pudendal Nerve Block and Caudal Block After Lateral Open Internal Sphincterotomy

    PubMed Central

    Alkhaldi, Hazem Mohammad; Salaita, Wasfi Mohammad; Shabaneh, Mohammad Ahmad; Al-Horut, Mohammad Ibrahim; Aldabbas, Raed Mohameh Abu Azzam; Uraiqat, Ahmad Ali

    2015-01-01

    Objective: To assess the postoperative outcome between pudendal nerve block and caudal block after open lateral internal sphincterotomy for chronic anal fissure. Methods: Our prospective, randomized and double blind investigation included 123 patients, of both sexes, aged 25-56 years, classed I-II by the American society of anesthesiologists and scheduled for elective open internal lateral sphincterotomy for anal fissure at King Hussein hospital, KHMC, Amman, Jordan, during the period from Jan. 2013 to Feb. 2015. Patients were divided into two groups. Group I included 62 patients (GI, n=62) operated under pudendal nerve block with local infiltration anesthesia and group II included 61 patients (GII, n=61) operated under caudal block. Postoperative pain, surgical duration, period of hospital admission, back to regular working activity and 4 weeks evaluation were compared between the two groups. Results: Postoperative outcome was more enhanced in group II but not significant than in group I. Patients in G-I experienced moderate pain for a mean of 5. 3 days in comparison with 4. 3 days in G-II. P>0. 05. Three patients (4. 9%) in G-II in comparison with 5 patients (8. 1%) in G-I had more hospital stay than 24 hours. Patients in G-II went back to normal activity after a mean of 7. 5 days in comparison with 8. 0 days in G-I. Conclusion: Undergoing open lateral internal sphincterotomy with the aid of Pudendal nerve block is an excellent, easy and safe alternative anesthesia to caudal anesthesia. PMID:26261389

  3. Anesthetic Efficacy of Bupivacaine Solutions in Inferior Alveolar Nerve Block

    PubMed Central

    Volpato, Maria Cristina; Ranali, José; Ramacciato, Juliana Cama; de Oliveira, Patrícia Cristine; Ambrosano, Glaúcia Maria Bovi; Groppo, Francisco Carlos

    2005-01-01

    The purpose of this study was to compare the anesthetic efficacy of 2 bupivacaine solutions. Twenty-two volunteers randomly received in a crossover, double-blinded manner 2 inferior alveolar nerve blocks with 1.8 mL of racemic bupivacaine and a mixture of 75% levobupivacaine and 25% dextrobupivacaine, both 0.5% and with 1 : 200,000 epinephrine. Before and after the injection, the first mandibular pre-molar was evaluated every 2 minutes until no response to the maximal output (80 reading) of the pulp tester and then again every 20 minutes. Data were analyzed using the Wilcoxon paired test and the paired t test. No differences were found between the solutions for onset and duration of pulpal anesthesia and duration of soft tissue anesthesia (P > .05). It was concluded that the solutions have similar anesthetic efficacy. PMID:16596912

  4. Ultrasound guided obturator nerve block: a single interfascial injection technique.

    PubMed

    Lee, Seong Heon; Jeong, Cheol Won; Lee, Hyun Jung; Yoon, Myung Ha; Kim, Woong Mo

    2011-12-01

    We describe a new technique of single interfascial injection for 25 patients scheduled for transurethral bladder tumor resection. An ultrasound probe was placed at the midline of inguinal crease and moved medially and caudally to visualize the fascial space between the adductor longus (or pectineus) and adductor brevis muscles. We injected 20 mL 1% lidocaine containing epinephrine into the interfascial space using a transverse plane approach to make an interfascial injection, not an intramuscular swelling pattern. And just distally, firm pressure was applied for 3 min. Afterwards, surgery was performed under spinal anesthesia. The time required for identification and location of the nerve was 20 ± 15 and 30 ± 15 s, respectively. Adductor muscle strength, which was measured with a sphygmomanometer, decreased in all patients, from 122 ± 26 mmHg before blockade to 63 ± 11 mmHg 5 min after blockade. No movement or palpable muscle twitching occurred in 23 cases, slight movement of the thigh not interfering with the surgical procedure was observed in 1 case, thus the obturator reflex was successfully inhibited in 96% of cases. Ultrasound-guided single interfascial injection is an easy and successful technique for obturator nerve block. PMID:21918855

  5. Real-time ultrasound-guided comparison of adductor canal block and psoas compartment block combined with sciatic nerve block in laparoscopic knee surgeries

    PubMed Central

    Messeha, Medhat M.

    2016-01-01

    Background: Lumbar plexus block, combined with a sciatic nerve block, is an effective locoregional anesthetic technique for analgesia and anesthesia of the lower extremity. The aim of this study was to compare the clinical results outcome of the adductor canal block versus the psoas compartment block combined with sciatic nerve block using real time ultrasound guidance in patients undergoing elective laparoscopic knee surgeries. Patients and Methods: Ninety patients who were undergoing elective laparoscopic knee surgeries were randomly allocated to receive a sciatic nerve block in addition to lumbar plexus block using either an adductor canal block (ACB) or a posterior psoas compartment approach (PCB) using 25 ml of bupivacine 0.5% with adrenaline 1:400,000 injection over 2-3 minutes while observing the distribution of the local anesthetic in real time. Successful nerve block was defined as a complete loss of pinprick sensation in the region that is supplied by the three nerves along with adequate motor block, 30 minutes after injection. The degree of motor block was evaluated 30 minutes after the block procedure. The results of the present study showed that the real time ultrasound guidance of PCB is more effective than ACB approach. Although the sensory blockade of the femoral nerve achieved equally by both techniques, the LFC and OBT nerves were faster and more effectively blocked with PCB technique. Also PCB group showed significant complete sensory block without need for general anesthesia, significant decrease in the post-operative VAS and significant increase time of first analgesic requirement as compared to the ACB group. Result and Conclusion: The present study demonstrates that blockade of lumber plexus by psoas compartment block is more effective in complete sensory block without general anesthesia supplementation in addition to decrease post-operative analgesic requirement than adductor canal block. PMID:27212766

  6. Ultrasound-guided continuous femoral nerve block vs continuous fascia iliaca compartment block for hip replacement in the elderly

    PubMed Central

    Yu, Bin; He, Miao; Cai, Guang-Yu; Zou, Tian-Xiao; Zhang, Na

    2016-01-01

    Abstract Background: Continuous femoral nerve block and fascia iliaca compartment block are 2 traditional anesthesia methods in orthopedic surgeries, but it is controversial which method is better. The objective of this study was to compare the practicality, efficacy, and complications of the 2 modalities in hip replacement surgery in the elderly and to assess the utility of a novel cannula-over-needle set. Methods: In this prospective, randomized controlled clinical investigation, 60 elderly patients undergoing hip replacement were randomly assigned to receive either continuous femoral nerve block or continuous fascia iliaca compartment block. After ultrasound-guided nerve block, all patients received general anesthesia for surgery and postoperative analgesia through an indwelling cannula. Single-factor analysis of variance was used to compare the outcome variables between the 2 groups. Results: There was a significant difference between the 2 groups in the mean visual analog scale scores (at rest) at 6 hours after surgery: 1.0 ± 1.3 in the femoral nerve block group vs 0.5 ± 0.8 in the fascia iliaca compartment block group (P < 0.05). The femoral nerve block group had better postoperative analgesia on the medial aspect of the thigh, whereas the fascia iliaca compartment block group had better analgesia on the lateral aspect of the thigh. There were no other significant differences between the groups. Conclusions: Both ultrasound-guided continuous femoral nerve block and fascia iliaca compartment block with the novel cannula-over-needle provide effective anesthesia and postoperative analgesia for elderly hip replacement patients. PMID:27759633

  7. Does the rectus femoris nerve block improve knee recurvatum in adult stroke patients? A kinematic and electromyographic study.

    PubMed

    Gross, R; Delporte, L; Arsenault, L; Revol, P; Lefevre, M; Clevenot, D; Boisson, D; Mertens, P; Rossetti, Y; Luauté, J

    2014-02-01

    Knee recurvatum (KR) during gait is common in hemiplegic patients. Quadriceps spasticity has been postulated as a cause of KR in this population. The aim of this study was to assess the role of rectus femoris spasticity in KR by using selective motor nerve blocks of the rectus femoris nerve in hemiparetic stroke patients. The data from six adult, post-stroke hemiplegic patients who underwent a rectus femoris nerve block for a stiff-knee gait were retrospectively analyzed. An extensive clinical and functional evaluation was performed and gait was assessed by motion analysis (kinematic, kinetic and electromyographic parameters) before and during the block realized using 2% lidocaine injected under a neurostimulation and ultrasonographic targeting procedure. The main outcome measures were the peak knee extension in stance and peak knee extensor moment obtained during gait analysis. No serious adverse effect of the nerve block was observed. The block allowed a reduction of rectus femoris overactivity in all patients. Peak knee extension and extensor moment in stance did not improve in any patient, but peak knee flexion during the swing phase was significantly higher after block (mean: 31.2° post, 26.4 pre, p < 0.05). Our results provide arguments against the hypothesis that the spasticity of the rectus femoris contributes to KR. PMID:24286615

  8. Effect of Preoperative Pain on Inferior Alveolar Nerve Block.

    PubMed

    Aggarwal, Vivek; Singla, Mamta; Subbiya, Arunajatesan; Vivekanandhan, Paramasivam; Sharma, Vikram; Sharma, Ritu; Prakash, Venkatachalam; Geethapriya, Nagarajan

    2015-01-01

    The present study tested the hypothesis that the amount and severity of preoperative pain will affect the anesthetic efficacy of inferior alveolar nerve block (IANB) in patients with symptomatic irreversible pulpitis. One-hundred seventy-seven adult volunteer subjects, actively experiencing pain in a mandibular molar, participated in this prospective double-blind study carried out at 2 different centers. The patients were classified into 3 groups on the basis of severity of preoperative pain: mild, 1-54 mm on the Heft-Parker visual analog scale (HP VAS); moderate, 55-114 mm; and severe, greater than 114 mm. After IANB with 1.8 mL of 2% lidocaine, endodontic access preparation was initiated. Pain during treatment was recorded using the HP VAS. The primary outcome measure was the ability to undertake pulp access and canal instrumentation with no or mild pain. The success rates were statistically analyzed by multiple logistic regression test. There was a significant difference between the mild and severe preoperative pain group (P = .03). There was a positive correlation between the values of preoperative and intraoperative pain (r = .2 and .4 at 2 centers). The amount of preoperative pain can affect the anesthetic success rates of IANB in patients with symptomatic irreversible pulpitis. PMID:26650491

  9. Delayed onset and long-lasting hemidiaphragmatic paralysis and cranial nerve deficit after interscalene nerve block for rotator cuff repair in beach chair position.

    PubMed

    Chiaghana, Chukwudi O; Awoniyi, Caleb A

    2016-11-01

    Hemidiaphragmatic paralysis is the most common adverse effect associated with interscalene block. In most cases, it resolves with the resolution of nerve blockade with only an estimated incidence of 0.048% persisting for longer duration. Occasionally, interscalene block is also associated with recurrent laryngeal nerve block and seldom with cranial nerve paresis. We present a case of delayed onset and prolonged hemidiaphragmatic paralysis that was associated with 3 cranial nerve deficits after interscalene nerve block for shoulder surgery performed under general anesthesia in the beach chair position. Etiology is unclear, but most likely multifactorial. PMID:27687453

  10. Advantages of caudal block over intrarectal local anesthesia plus periprostatic nerve block for transrectal ultrasound guided prostate biopsy

    PubMed Central

    Wang, Na; Fu, Yaowen; Ma, Haichun; Wang, Jinguo; Gao, Yang

    2016-01-01

    Objective: To compare caudal block with intrarectal local anesthesia plus periprostatic nerve block for transrectal ultrasound guided prostate biopsy. Methods: One hundred and ninety patients scheduled for transrectal ultrasound guided prostate biopsy were randomized equally into Group-A who received caudal block (20 ml 1.2% lidocaine) and Group-B who received intrarectal local anesthesia (0.3% oxybuprocaine cream) plus periprostatic nerve block (10 ml 1% lidocaine plus 0.5% ropivacaine) before biopsy. During and after the procedure, the patients rated the level of pain/discomfort at various time points. Complications during the whole study period and the patient overall satisfaction were also evaluated. Results: More pain and discomfort was detected during periprostatic nerve block than during caudal block. Pain and discomfort was significantly lower during prostate biopsy and during the manipulation of the probe in the rectum in Group-A than in Group-B. No significant differences were detected in the pain intensity after biopsy and side effects between the two groups. Conclusions: Caudal block provides better anesthesia than periprostatic nerve block plus intrarectal local anesthesia for TRUS guided prostate biopsy without an increase of side effects. PMID:27648052

  11. Ultrasound-Guided Greater Auricular Nerve Block as Sole Anesthetic for Ear Surgery.

    PubMed

    Ritchie, Michael K; Wilson, Colin A; Grose, Brian W; Ranganathan, Pavithra; Howell, Stephen M; Ellison, Matthew B

    2016-04-26

    A greater auricular nerve (GAN) block was used as the sole anesthetic for facial surgery in an 80-year-old male patient with multiple comorbidities which would have made general anesthesia challenging. The GAN provides sensation to the ear, mastoid process, parotid gland, and angle of the mandible. In addition to anesthesia for operating room surgery, the GAN block can be used for outpatient or emergency department procedures without the need for a separate anesthesia team. Although this nerve block has been performed using landmark-based techniques, the ultrasound-guided version offers several potential advantages. These advantages include increased reliability of the nerve block, as well as prevention of inadvertent vascular puncture or blockade of the phrenic nerve, brachial plexus, or deep cervical plexus. The increasing access to ultrasound technology for medical care providers outside the operating room makes this ultrasound guided block an increasingly viable alternative. PMID:27478586

  12. The efficacy of combined regional nerve blocks in awake orotracheal fiberoptic intubation

    PubMed Central

    Chatrath, Veena; Sharan, Radhe; Jain, Payal; Bala, Anju; Ranjana; Sudha

    2016-01-01

    Aims of Study: To evaluate the efficacy, hemodynamic changes, and patient comfort during awake fiberoptic intubation done under combined regional blocks. Materials and Methods: In the present observational study, 50 patients of American Society of Anesthesiologists ( ASA) Grade I–II, Mallampati Grade I–IV were given nerve blocks - bilateral glossopharyngeal nerve block, bilateral superior laryngeal nerve block, and recurrent laryngeal nerve block before awake fiberoptic intubation using 2% lidocaine. Results: Procedure was associated with minimal increases in hemodynamic parameters during the procedure and until 3 min after it. Most of the intubations were being carried out within 3 min. Patient comfort was satisfactory with 90% of patients having favorable grades. Discussion: The most common cause of mortality and serious morbidity due to anesthesia is from airway problems. One-third of all anesthetic deaths are due to failure to intubate and ventilate. Awake flexible fiberoptic intubation under local anesthesia is now an accepted technique for managing such situations. In awake patient's anatomy, muscle tone, airway protection, and ventilation are preserved, but it is essential to sufficiently anesthetize the upper airway before the performance of awake fiberoptic bronchoscope-guided intubation to ensure patient comfort and cooperation for which in our study we used the nerve block technique. Conclusion: A properly performed technique of awake fiberoptic intubation done under combined regional nerve blocks provides good intubating conditions, patient comfort and safety and results in minimal hemodynamic changes. PMID:27212757

  13. Transsacral S2-S4 nerve block for vaginal pain due to pudendal neuralgia.

    PubMed

    Cok, Oya Yalcin; Eker, H Evren; Cok, Tayfun; Akin, Sule; Aribogan, Anis; Arslan, Gulnaz

    2011-01-01

    Pudendal neuralgia is a type of neuropathic pain experienced predominantly while sitting, and causes a substantial decrease in quality of life in affected patients. Pudendal nerve block is a diagnostic and therapeutic option for pudendal neuralgia. Transsacral block at S2 through S4 results in pudendal nerve block, which is an option for successful relief of pain due to pudendal nerve injury. Herein is reported blockade of S2 through S4 using lidocaine and methylprednisolone for successful treatment of pudendal neuralgia in 2 patients with severe chronic vaginal pain. The patients, aged 44 and 58 years, respectively, were referred from the Gynecology Department to the pain clinic because of burning, stabbing, electric shock-like, unilateral pain localized to the left portion of the vagina and extending to the perineum. Their initial pain scores were 9 and 10, respectively, on a numeric rating scale. Both patients refused pudendal nerve block using classical techniques. Therefore, diagnostic transsacral S2-S4 nerve block was performed using lidocaine 1%, and was repeated using lidocaine 1% and methylprednisolone 80 mg after confirming block efficiency as demonstrated by an immediate decrease in pain scores. After 1 month, pain scores were 1 and 0, respectively, and both patients were free of pain at 6-month follow up. It is suggested that blockade of S2 through S4 using lidocaine and methylprednisolone is an effective treatment option in patients with chronic pudendal neuralgia when traditional pudendal nerve block is not applicable.

  14. Comparison of Adductor Canal Block and Femoral Nerve Block for Postoperative Pain in Total Knee Arthroplasty

    PubMed Central

    Dong, Cui-Cui; Dong, Shu-Ling; He, Fu-Cheng

    2016-01-01

    Abstract A total knee arthroplasty (TKA) has always been associated with moderate-to-severe pain. A systematic review of randomized controlled trials (RCTs) and non-RCTs was performed to evaluate the efficacy and safety of pain control of adductor canal block (ACB) and femoral nerve block (FNB) after TKA. Relevant literatures about the ACB and FNB after TKA for reducing pain were searched from Medline (1996-January, 2015), Embase (1980-January, 2015), PubMed (1980-January, 2015), Web of Science (1980-January, 2015), and The Cochrane Central Register of Controlled Trials. High-quality RCTs and non-RCTs were picked to evaluate the visual analogue scale (VAS) and other outcome. This systematic review and meta-analysis were performed according to the PRISMA statement criteria. The software RevMan 5.30 was used for the meta-analysis. Eight literatures fitted into the inclusion criteria. There were no significant differences in VAS score with rest or mobilization at 4, 24, and 48 h between ACB group and FNB group. There were also no significant differences in the strength of quadriceps and adductor, the length of hospital stay, and complications of vomiting and nausea. Present meta-analysis indicated that ACB shows no superiority than FNB group. Both of them can reduce the pain score after TKA. As referred to which method to adopt, it is determined by the preference of the surgeons and anesthesiologists. PMID:27015172

  15. Intercostal nerves block for mastectomy in two patients with advanced breast malignancy.

    PubMed

    Kolawole, Israel K; Adesina, Michael D; Olaoye, Iyiade O

    2006-03-01

    Regional anesthesia is recognized as an alternative to general anesthesia for modern breast cancer surgery. Various techniques of block have been described. Each has its unique problems. Regional anesthesia was chosen for simple mastectomy in two patients with advanced breast malignancy, due to compromised pulmonary status resulting from widespread malignant infiltration of both lungs. We used intercostal nerves block. The block was supplemented with an infraclavicular infiltration to interrupt the branches of the superficial cervical plexus that provide sensation to the upper chest wall and subcutaneous infiltration in the midline to block the nerve supply from the contralateral side. Anesthesia was generally effective and the operations were uneventful. Both patients and surgeons expressed satisfaction. We conclude that where patients have significant comorbidities that make general anesthesia undesirable, the use of intercostal nerves block remains a safe and reliable anesthetic option that allows the patient access to surgery for simple mastectomy.

  16. Infra-orbital nerve block anesthesia–extended coverage using intra-oral ‘molar approach’

    PubMed Central

    Bali, Rishi Kumar; Nautiyal, Vijay P; Sharma, Praveen; Sharma, Rohit

    2012-01-01

    The maxillary teeth are supplied by the anterior, middle and posterior superior alveolar nerves. The anterior and middle superior alveolar (AMSA) nerves exit the skull from the infra-orbital foramen, where they can be blocked for procedures on the maxillary anteriors and premolars. Sometimes, the middle superior alveolar nerve has a variant course and is not blocked by the conventional block technique. A new technique has been described for blocking the AMSA nerves, keeping in view the alternate pathway of the middle superior alveolar nerve. PMID:25756021

  17. Maxillary nerve block in management of maxillary bone fractures: Our experience

    PubMed Central

    Thangavelu, K; Kumar, N. Senthil; Kannan, R.; Arunkumar, J.; Rethish, E.

    2012-01-01

    Background and Objectives: The objective of this study is to evaluate the intraoral high tuberocity maxillary nerve block technique in zygoma and arch fracture reduction and fixation. Study and Design: This study was carried out at Arvind Multi-Specialty Hospital, Namakkal, Tamil Nadu on seven male patients with zygomatic bone and arch fracture. Materials and Methods: Intraoral high tuberocity maxillary nerve block administered in seven patients for management of isolated zygomatic bone and arch fracture. Lidocaine 2% measuring 4 mL with 1:80000 adrenaline anesthetic solutions was used to anesthetize maxillary nerve through a 3.2 cm length and 24G, needle. The following parameters were evaluated namely onset of anesthesia, nerve block duration, outcome of treatment and Patient's comfort. Results: The blocks were effective and patients were comfortable without pain during initial stage of surgery, but in latter stages two patients had mild to moderate pain. Duration of block varied from 60 to 90 min while onset varied from 3 to 10 min. There were vascular punctures in three patients, however, without hematoma. Conclusions: The maxillary nerve block is a good alternative option in selective cases of zygomatic bone fracture reduction. PMID:25885504

  18. Risk of Encountering Dorsal Scapular and Long Thoracic Nerves during Ultrasound-guided Interscalene Brachial Plexus Block with Nerve Stimulator

    PubMed Central

    Kim, Yeon Dong; Yu, Jae Yong; Shim, Junho; Heo, Hyun Joo

    2016-01-01

    Background Recently, ultrasound has been commonly used. Ultrasound-guided interscalene brachial plexus block (IBPB) by posterior approach is more commonly used because anterior approach has been reported to have the risk of phrenic nerve injury. However, posterior approach also has the risk of causing nerve injury because there are risks of encountering dorsal scapular nerve (DSN) and long thoracic nerve (LTN). Therefore, the aim of this study was to evaluate the risk of encountering DSN and LTN during ultrasound-guided IBPB by posterior approach. Methods A total of 70 patients who were scheduled for shoulder surgery were enrolled in this study. After deciding insertion site with ultrasound, awake ultrasound-guided IBPB with nerve stimulator by posterior approach was performed. Incidence of muscle twitches (rhomboids, levator scapulae, and serratus anterior muscles) and current intensity immediately before muscle twitches disappeared were recorded. Results Of the total 70 cases, DSN was encountered in 44 cases (62.8%) and LTN was encountered in 15 cases (21.4%). Both nerves were encountered in 10 cases (14.3%). Neither was encountered in 21 cases (30.4%). The average current measured immediately before the disappearance of muscle twitches was 0.44 mA and 0.50 mA at DSN and LTN, respectively. Conclusions Physicians should be cautious on the risk of injury related to the anatomical structures of nerves, including DSN and LTN, during ultrasound-guided IBPB by posterior approach. Nerve stimulator could be another option for a safer intervention. Moreover, if there is a motor response, it is recommended to select another way to secure better safety. PMID:27413483

  19. Anesthetic efficacy of a combination of hyaluronidase and lidocaine with epinephrine in inferior alveolar nerve blocks.

    PubMed Central

    Ridenour, S.; Reader, A.; Beck, M.; Weaver, J.

    2001-01-01

    The purpose of this prospective, randomized, double-blind study was to determine the anesthetic efficacy of a buffered lidocaine with epinephrine solution compared to a combination buffered lidocaine with epinephrine plus hyaluronidase solution in inferior alveolar nerve blocks. Thirty subjects randomly received an inferior alveolar nerve block using 1 of the 2 solutions at 2 separate appointments using a repeated-measures design. Mandibular anterior and posterior teeth were blindly pulp tested at 4-minute cycles for 60 minutes postinjection. No response from the subject to the maximum output (80 reading) of the pulp tester was used as the criterion for pulpal anesthesia. Anesthesia was considered successful when 2 consecutive readings of 80 were obtained. A postoperative survey was used to measure pain and trismus. The results demonstrated 100% of the subjects had profound lip numbness with both solutions for inferior alveolar nerve blocks. The anesthetic success rates for individual teeth ranged from 20 to 80%. There were no significant differences (P > .05) between the 2 solutions. However, the combination lidocaine/hyaluronidase solution resulted in a significant increase in postoperative pain and trismus. It was concluded that adding hyaluronidase to a buffered lidocaine solution with epinephrine did not statistically increase the incidence of pulpal anesthesia in inferior alveolar nerve blocks and, because of its potential tissue damaging effect, it should not be added to local anesthetic solutions for inferior alveolar nerve blocks. PMID:11495405

  20. A Central Role for Sympathetic Nerves in Herpes Stromal Keratitis in Mice

    PubMed Central

    Yun, Hongmin; Lathrop, Kira L.; Hendricks, Robert L.

    2016-01-01

    Purpose Herpes simplex virus type 1 (HSV-1) is a neurotrophic virus that can cause herpes stromal keratitis (HSK), a severe corneal inflammation that can lead to corneal scarring and blindness. This study identified neurologic changes that occur in HSV-1–infected corneas and related them to HSV-1–induced immunopathology. Methods Corneas of BALB/c and C57BL/6 mice were infected with HSV-1 strains that induce HSK. Changes in sensory nerves were identified by immunofluorescence staining of sensory and sympathetic nerves for substance P (SP) and tyrosine hydroxylase (TH), respectively, and confocal microscopic examination. Some mice received superior cervical ganglionectomy (SCGx) to eliminate sympathetic nerves from the cornea. Results Normal corneas exclusively expressed sensory nerves that entered the stroma as large nerve stalks, branched to form a plexus at the epithelial/stromal interface, and extended termini into the epithelium. These nerves completely retracted from the infected cornea and were replaced by sympathetic nerves that sprouted extensively to hyperinnervate the corneal stroma but failed to form a plexus or extend termini into the epithelium. The hyperinnervating nerves expressed the sympathetic nerve marker TH and their invasion was blocked by performing SCGx. Moreover, the corneal opacity and neovascularization that normally characterizes HSK in this mouse model were largely abrogated by SCGx. Sensory nerves reinnervated infected corneas following SCGx, reformed a nerve plexus, and extended termini into the epithelium resulting in recovery of corneal sensitivity. Conclusions Sympathetic nerves have a central role in HSK in mice, preventing reinnervation by sensory nerves and promoting severe and persistent corneal inflammation. PMID:27070108

  1. Peripheral nerve blocks as the sole anesthetic technique in a patient with severe Duchenne muscular dystrophy.

    PubMed

    Bang, Seung Uk; Kim, Yee Suk; Kwon, Woo Jin; Lee, Sang Mook; Kim, Soo Hyang

    2016-04-01

    General anesthesia and central neuraxial blockades in patients with severe Duchenne muscular dystrophy are associated with high risks of complications, including rhabdomyolysis, malignant hyperthermia, hemodynamic instability, and postoperative mechanical ventilation. Here, we describe peripheral nerve blocks as a safe approach to anesthesia in a patient with severe Duchenne muscular dystrophy who was scheduled to undergo surgery. A 22-year-old male patient was scheduled to undergo reduction and internal fixation of a left distal femur fracture. He had been diagnosed with Duchenne muscular dystrophy at 5 years of age, and had no locomotive capability except for that of the finger flexors and toe extensors. He had developed symptoms associated with dyspnea 5 years before and required intermittent ventilation. We blocked the femoral nerve, lateral femoral cutaneous nerve, and parasacral plexus under ultrasound on the left leg. The patient underwent a successful operation using peripheral nerve blocks with no complications. In conclusion general anesthesia and central neuraxial blockades in patients with severe Duchenne muscular dystrophy are unsafe approaches to anesthesia because of hemodynamic instability and respiratory depression. Peripheral nerve blocks are the best way to reduce the risks of critical complications, and are a safe and feasible approach to anesthesia in patients with severe Duchenne muscular dystrophy.

  2. Bupivacaine-induced cellular entry of QX-314 and its contribution to differential nerve block

    PubMed Central

    Brenneis, C; Kistner, K; Puopolo, M; Jo, S; Roberson, DP; Sisignano, M; Segal, D; Cobos, EJ; Wainger, BJ; Labocha, S; Ferreirós, N; Hehn, C; Tran, J; Geisslinger, G; Reeh, PW; Bean, BP; Woolf, C J

    2014-01-01

    Background and Purpose: Selective nociceptor fibre block is achieved by introducing the cell membrane impermeant sodium channel blocker lidocaine N-ethyl bromide (QX-314) through transient receptor potential V1 (TRPV1) channels into nociceptors. We screened local anaesthetics for their capacity to activate TRP channels, and characterized the nerve block obtained by combination with QX-314. Experimental Approach: We investigated TRP channel activation in dorsal root ganglion (DRG) neurons by calcium imaging and patch-clamp recordings, and cellular QX-314 uptake by MS. To characterize nerve block, compound action potential (CAP) recordings from isolated nerves and behavioural responses were analysed. Key Results: Of the 12 compounds tested, bupivacaine was the most potent activator of ruthenium red-sensitive calcium entry in DRG neurons and activated heterologously expressed TRPA1 channels. QX-314 permeated through TRPA1 channels and accumulated intracellularly after activation of these channels. Upon sciatic injections, QX-314 markedly prolonged bupivacaine's nociceptive block and also extended (to a lesser degree) its motor block. Bupivacaine's blockade of C-, but not A-fibre, CAPs in sciatic nerves was extended by co-application of QX-314. Surprisingly, however, this action was the same in wild-type, TRPA1-knockout and TRPV1/TRPA1-double knockout mice, suggesting a TRP-channel independent entry pathway. Consistent with this, high doses of bupivacaine promoted a non-selective, cellular uptake of QX-314. Conclusions and Implications: Bupivacaine, combined with QX-314, produced a long-lasting sensory nerve block. This did not require QX-314 permeation through TRPA1, although bupivacaine activated these channels. Regardless of entry pathway, the greatly extended duration of block produced by QX-314 and bupivacaine may be clinically useful. PMID:24117225

  3. DEVELOPMENT OF RETROBULBAR AND AURICULOPALPEBRAL NERVE BLOCKS IN CALIFORNIA SEA LIONS (ZALOPHUS CALIFORNIANUS).

    PubMed

    Gutiérrez, J; Simeone, C; Gulland, F; Johnson, S

    2016-03-01

    Eye lesions are commonly observed in pinnipeds. Clinical assessment is challenging because animals are often blepharospastic and under inhalant anesthesia the globe rotates ventrally, making observation difficult. Retrobulbar and auriculopalpebral nerve block techniques have been developed in other species to alleviate these difficulties and allow for a more thorough ophthalmic exam. Ocular nerve block techniques were developed for California sea lions (CSLs) (Zalophus californianus) using lidocaine hydrochloride 2%. To develop the retrobulbar block, a variety of needle sizes, anatomic approaches, and volumes of methylene blue were injected into the orbits of 10 CSL cadavers. An optimal technique, based on desired distribution of methylene blue dye into periocular muscles and tissues, was determined to be a two-point (ventrolateral and ventromedial) transpalpebral injection with a 20-ga, 1 1/2-inch needle. This technique was then tested using lidocaine on 26 anesthetized animals prior to euthanasia, and on one case with clinical ocular disease. A dose of 4 mg/kg of lidocaine was considered ideal, with positive results and minimal complications. The retrobulbar block had a 76.9% rate of success (using 4 mg/kg of lidocaine), which was defined as the globe returning at least halfway to its central orientation with mydriasis. No systemic adverse effects were noted with this technique. The auriculopalpebral nerve block was also adapted for CSLs from techniques described in dogs, cattle, and horses. Lidocaine was injected (2-3 ml) by subcutaneous infiltration lateral to the orbital rim, where the auriculopalpebral nerve branch courses over the zygomatic arch. This block was used in five blepharospastic animals that were anesthetized for ophthalmic examinations. The auriculopalpebral nerve block was successful in 60% of the cases, which was defined as reduction or elimination of blepharospasm for up to 3 hr. Success appeared to be dependent more on the location of

  4. DEVELOPMENT OF RETROBULBAR AND AURICULOPALPEBRAL NERVE BLOCKS IN CALIFORNIA SEA LIONS (ZALOPHUS CALIFORNIANUS).

    PubMed

    Gutiérrez, J; Simeone, C; Gulland, F; Johnson, S

    2016-03-01

    Eye lesions are commonly observed in pinnipeds. Clinical assessment is challenging because animals are often blepharospastic and under inhalant anesthesia the globe rotates ventrally, making observation difficult. Retrobulbar and auriculopalpebral nerve block techniques have been developed in other species to alleviate these difficulties and allow for a more thorough ophthalmic exam. Ocular nerve block techniques were developed for California sea lions (CSLs) (Zalophus californianus) using lidocaine hydrochloride 2%. To develop the retrobulbar block, a variety of needle sizes, anatomic approaches, and volumes of methylene blue were injected into the orbits of 10 CSL cadavers. An optimal technique, based on desired distribution of methylene blue dye into periocular muscles and tissues, was determined to be a two-point (ventrolateral and ventromedial) transpalpebral injection with a 20-ga, 1 1/2-inch needle. This technique was then tested using lidocaine on 26 anesthetized animals prior to euthanasia, and on one case with clinical ocular disease. A dose of 4 mg/kg of lidocaine was considered ideal, with positive results and minimal complications. The retrobulbar block had a 76.9% rate of success (using 4 mg/kg of lidocaine), which was defined as the globe returning at least halfway to its central orientation with mydriasis. No systemic adverse effects were noted with this technique. The auriculopalpebral nerve block was also adapted for CSLs from techniques described in dogs, cattle, and horses. Lidocaine was injected (2-3 ml) by subcutaneous infiltration lateral to the orbital rim, where the auriculopalpebral nerve branch courses over the zygomatic arch. This block was used in five blepharospastic animals that were anesthetized for ophthalmic examinations. The auriculopalpebral nerve block was successful in 60% of the cases, which was defined as reduction or elimination of blepharospasm for up to 3 hr. Success appeared to be dependent more on the location of

  5. Ultrasound-guided dorsal penile nerve block for ED paraphimosis reduction.

    PubMed

    Flores, Stefan; Herring, Andrew A

    2015-06-01

    Adequate anesthesia for emergency department management of painful penile conditions such as paraphimosis or priapism is often both technically challenging and inconsistent using traditional landmark-based techniques of the dorsal penile block (DPB). The pudendal nerves branch to form the paired dorsal nerves of the penis providing sensory innervation to the skin of both the dorsal and ventral aspects of the penis. "Blind" DPB techniques tend to rely on subtle tactile feedback from the needle and visual landmark approximation to identify the appropriate subpubic fascial compartment for injection. The landmark-based DPB is not standardized with options including “10 o'clock and 2 o'clock” infrapubic injections with or without ventral infiltration or a ring block. Given the lack of standardization and inherent technical imprecision with the landmark-based DPB, large volumes of local anesthetic (up to 50 mL) are sometimes required to achieve a clinically adequate block. In addition, inadvertent injection into the corpora cavernosa may occur. More recently, an ultrasound-guided approach has been developed. Using ultrasound, the dorsal penile nerves can be precisely targeted in the fascial compartment just deep to Buck fascia, potentially increasing block success rate and reducing the need for large local anesthetic volumes. Herein, we report the first adult case of an ultrasound-guided dorsal penile nerve block performed in the emergency department for the reduction of a paraphimosis and review the relevant penile anatomy and technical details of the procedure. PMID:25605058

  6. Efficacy of ultrasound-guided obturator nerve block in transurethral surgery

    PubMed Central

    Thallaj, Ahmed; Rabah, Dany

    2011-01-01

    Background: During transurethral resection surgery (TUR), accidental stimulation of the obturator nerve can cause violent adductor contraction, leading to serious intraoperative complications. General anesthesia with muscle relaxation is currently the preferred technique for TUR surgery. Spinal anesthesia combined with obturator nerve block has also been used for TUR surgery in geriatric population. Blind, anatomical methods for identifying the obturator nerve are often unsatisfactory. Therefore, we conducted this prospective study to validate the efficacy of ultrasound-guided obturator nerve block (USONB) during TUR procedures. Methods: Eighteen male patients undergoing TURP surgery under spinal anesthesia were included in the study. Bilateral USONB with maximum 20 ml of 1% lidocaine per patient was performed. An independent observer was present to monitor any adduction movements during the operation and to record patient and surgeon satisfactions. Results: In all patients, obturator nerve was visualized from the first attempt, requiring an average of 4.3 min for blocking of each side. USONB was successful (97.2%) in preventing an adductor spasm in all except one patient. Patient’s and surgeon’s satisfaction were appropriate. In all patients, adductor muscle strength recovered fully within 2 h following the surgical procedure. Conclusions: USONB is safe and effective during TUR surgery. It provides optimal intra-and postoperative conditions. PMID:21655015

  7. High Flow Priapism in a Pediatric Patient after Circumcision with Dorsal Penile Nerve Block.

    PubMed

    Granieri, Michael A; Fantony, Joseph J; Routh, Jonathan C

    2016-01-01

    We report the first documented case of high flow priapism after circumcision with dorsal penile nerve block. A 7-year-old male who had undergone circumcision three years before presented to our institution with a 3-year history of persistent nonpainful erections. Workup revealed a high flow priapism and, after discussion of the management options, the patient's family elected continued observation. PMID:27648333

  8. High Flow Priapism in a Pediatric Patient after Circumcision with Dorsal Penile Nerve Block

    PubMed Central

    Fantony, Joseph J.; Routh, Jonathan C.

    2016-01-01

    We report the first documented case of high flow priapism after circumcision with dorsal penile nerve block. A 7-year-old male who had undergone circumcision three years before presented to our institution with a 3-year history of persistent nonpainful erections. Workup revealed a high flow priapism and, after discussion of the management options, the patient's family elected continued observation. PMID:27648333

  9. Virtual reality-based regional anaesthesia simulator for axillary nerve blocks.

    PubMed

    Ullrich, Sebastian; Frommen, Thorsten; Rossaint, Rolf; Kuhlen, Torsten

    2009-01-01

    In this paper, we present a simulator for regional anaesthesia for nerve blocks in the axillary plexus region. We use a novel approach based on electric distance to simulate electronic impulse transmission through soft tissue. The traversal of electrons emitted from the needle tip is calculated by modified pathfinding algorithms. Kinematic algorithms visualize the motor response of the forearm by skeletal animation. PMID:19377191

  10. High Flow Priapism in a Pediatric Patient after Circumcision with Dorsal Penile Nerve Block

    PubMed Central

    Fantony, Joseph J.; Routh, Jonathan C.

    2016-01-01

    We report the first documented case of high flow priapism after circumcision with dorsal penile nerve block. A 7-year-old male who had undergone circumcision three years before presented to our institution with a 3-year history of persistent nonpainful erections. Workup revealed a high flow priapism and, after discussion of the management options, the patient's family elected continued observation.

  11. Thou shalt not fall! Decreasing falls in the postoperative orthopedic patient with a femoral nerve block.

    PubMed

    Foisy, Kimberly

    2013-01-01

    A Transforming Care at the Bedside model was used to decrease falls in the femoral nerve block (FNB) patient population on a 32-bed orthopedic/neurologic unit in a community hospital setting. A multifaceted, strategic practice and educational bundle was implemented, resulting in a 75% decrease in falls among patients with FNB.

  12. Continuous Ilioinguinal-iliohypogastric Nerve Block for Groin Pain in a Breast-feeding Patient after Cesarean Delivery.

    PubMed

    Kim, Eun Soo; Kim, Hae Kyu; Baik, Ji Seok; Ji, Young Tae

    2016-07-01

    Ilioinguinal and iliohypogastric (II/IH) nerve injury is one of the most common nerve injuries following pelvic surgery, especially with the Pfannenstiel incision. We present a case of intractable groin pain, successfully treated with a continuous II/IH nerve block. A 33-year-old woman, following emergency cesarean section due to cephalopelvic disproportion, presented numbness in left inguinal area and severe pain on the labia on the second postoperative day. The pain was burning, lancinating, and exacerbated by standing or movement. However, she didn't want to take additional medicine because of breast-feeding. A diagnostic II/IH nerve block produced a substantial decrease in pain. She underwent a continuous II/IH nerve block with a complete resolution of pain within 3 days. A continuous II/IH nerve block might be a goodoption for II/IH neuropathy with intractable groin pain in breast-feeding mothers without adverse drug reactions in their infants.

  13. Local Anesthetic Peripheral Nerve Block Adjuvants for Prolongation of Analgesia: A Systematic Qualitative Review

    PubMed Central

    Kirksey, Meghan A.; Haskins, Stephen C.; Cheng, Jennifer; Liu, Spencer S.

    2015-01-01

    Background The use of peripheral nerve blocks for anesthesia and postoperative analgesia has increased significantly in recent years. Adjuvants are frequently added to local anesthetics to prolong analgesia following peripheral nerve blockade. Numerous randomized controlled trials and meta-analyses have examined the pros and cons of the use of various individual adjuvants. Objectives To systematically review adjuvant-related randomized controlled trials and meta-analyses and provide clinical recommendations for the use of adjuvants in peripheral nerve blocks. Methods Randomized controlled trials and meta-analyses that were published between 1990 and 2014 were included in the initial bibliographic search, which was conducted using Medline/PubMed, Cochrane Central Register of Controlled Trials, and EMBASE. Only studies that were published in English and listed block analgesic duration as an outcome were included. Trials that had already been published in the identified meta-analyses and included adjuvants not in widespread use and published without an Investigational New Drug application or equivalent status were excluded. Results Sixty one novel clinical trials and meta-analyses were identified and included in this review. The clinical trials reported analgesic duration data for the following adjuvants: buprenorphine (6), morphine (6), fentanyl (10), epinephrine (3), clonidine (7), dexmedetomidine (7), dexamethasone (7), tramadol (8), and magnesium (4). Studies of perineural buprenorphine, clonidine, dexamethasone, dexmedetomidine, and magnesium most consistently demonstrated prolongation of peripheral nerve blocks. Conclusions Buprenorphine, clonidine, dexamethasone, magnesium, and dexmedetomidine are promising agents for use in prolongation of local anesthetic peripheral nerve blocks, and further studies of safety and efficacy are merited. However, caution is recommended with use of any perineural adjuvant, as none have Food and Drug Administration approval, and

  14. Combination of diagnostic medial calcaneal nerve block followed by pulsed radiofrequency for plantar fascitis pain: A new modality.

    PubMed

    Thapa, Deepak; Ahuja, Vanita

    2014-03-01

    Plantar fasciitis (PF) is the most common cause of chronic heel pain which may be bilateral in 20 to 30% of patients. It is a very painful and disabling condition which can affect the quality of life. The management includes both pharmacological and operative procedures with no single proven effective treatment modality. In the present case series, we managed three patients with PF (one with bilateral PF). Following a diagnostic medial calcaneal nerve (MCN) block at its origin, we observed reduction in verbal numerical rating scale (VNRS) in all the three patients. Two patients has relapse of PF pain which was managed with MCN block followed with pulsed radio frequency (PRF). All the patients were pain-free at the time of reporting. This case series highlights the possible role of combination of diagnostic MCN block near its origin followed with PRF as a new modality in management of patients with PF.

  15. Frequency- and amplitude-transitioned waveforms mitigate the onset response in high-frequency nerve block

    NASA Astrophysics Data System (ADS)

    Gerges, Meana; Foldes, Emily L.; Ackermann, D. Michael; Bhadra, Narendra; Bhadra, Niloy; Kilgore, Kevin L.

    2010-12-01

    High-frequency alternating currents (HFAC) have proven to be a reversible and rapid method of blocking peripheral nerve conduction, holding promise for treatment of disorders associated with undesirable neuronal activity. The delivery of HFAC is characterized by a transient period of neural firing at its inception, termed the 'onset response'. The onset response is minimized for higher frequencies and higher amplitudes, but requires larger currents. However, the complete block can be maintained at lower frequencies and amplitudes, using lower currents. In this in vivo study on whole mammalian peripheral nerves, we demonstrate a method to minimize the onset response by initiating the block using a stimulation paradigm with a high frequency and large amplitude, and then transitioning to a low-frequency and low-amplitude waveform, reducing the currents required to maintain the conduction block. In five of six animals, it was possible to transition from a 30 kHz to a 10 kHz waveform without inducing any transient neural firing. The minimum transition time was 0.03 s. Transition activity was minimized or eliminated with longer transition times. The results of this study show that this method is feasible for achieving a nerve block with minimal onset responses and current amplitude requirements.

  16. High-frequency stimulation selectively blocks different types of fibers in frog sciatic nerve.

    PubMed

    Joseph, Laveeta; Butera, Robert J

    2011-10-01

    Conduction block using high-frequency alternating current (HFAC) stimulation has been shown to reversibly block conduction through various nerves. However, unlike simulations and experiments on myelinated fibers, prior experimental work in our lab on the sea-slug, Aplysia, found a nonmonotonic relationship between frequency and blocking thresholds in the unmyelinated fibers. To resolve this discrepancy, we investigated the effect of HFAC waveforms on the compound action potential of the sciatic nerve of frogs. Maximal stimulation of the nerve produces a compound action potential consisting of the A-fiber and C-fiber components corresponding to the myelinated and unmyelinated fibers' response. In our study, HFAC waveforms were found to induce reversible block in the A-fibers and C-fibers for frequencies in the range of 5-50 kHz and for amplitudes from 0.1-1 mA. Although the A-fibers demonstrated the monotonically increasing threshold behavior observed in published literature, the C-fibers displayed a nonmonotonic relationship, analogous to that observed in the unmyelinated fibers of Aplysia. This differential blocking behavior observed in myelinated and unmyelinated fibers during application of HFAC waveforms has diverse implications for the fields of selective stimulation and pain management.

  17. US-Guided Femoral and Sciatic Nerve Blocks for Analgesia During Endovenous Laser Ablation

    SciTech Connect

    Yilmaz, Saim Ceken, Kagan; Alimoglu, Emel; Sindel, Timur

    2013-02-15

    Endovenous laser ablation may be associated with significant pain when performed under standard local tumescent anesthesia. The purpose of this study was to investigate the efficacy of femoral and sciatic nerve blocks for analgesia during endovenous ablation in patients with lower extremity venous insufficiency. During a 28-month period, ultrasound-guided femoral or sciatic nerve blocks were performed to provide analgesia during endovenous laser ablation in 506 legs and 307 patients. The femoral block (n = 402) was performed at the level of the inguinal ligament, and the sciatic block at the posterior midthigh (n = 124), by injecting a diluted lidocaine solution under ultrasound guidance. After the blocks, endovenous laser ablations and other treatments (phlebectomy or foam sclerotherapy) were performed in the standard fashion. After the procedures, a visual analogue pain scale (1-10) was used for pain assessment. After the blocks, pain scores were 0 or 1 (no pain) in 240 legs, 2 or 3 (uncomfortable) in 225 legs, and 4 or 5 (annoying) in 41 legs. Patients never experienced any pain higher than score 5. The statistical analysis revealed no significant difference between the pain scores of the right leg versus the left leg (p = 0.321) and between the pain scores after the femoral versus sciatic block (p = 0.7). Ultrasound-guided femoral and sciatic nerve blocks may provide considerable reduction of pain during endovenous laser and other treatments, such as ambulatory phlebectomy and foam sclerotherapy. They may make these procedures more comfortable for the patient and easier for the operator.

  18. Selective degeneration of optic nerve fibres in the cat produced by a pressure block.

    PubMed Central

    Burke, W; Cottee, L J; Garvey, J; Kumarasinghe, R; Kyriacou, C

    1986-01-01

    Using a technique described previously, we have applied pressure to the optic nerve of a cat sufficient to cause conduction block of the t1 response (the response of the Y optic nerve fibres). A greater pressure, usually sufficient to cause a transient block of the t2 response (the response of the X fibres), leads to degeneration of the Y axons caudal to the block. This is demonstrated by the disappearance of the t1 response in this region after 4-5 days and by the presence in electron micrographs of degenerating large (Y) fibres. Some small fibres also show degeneration, but the medium (X) fibres are largely spared. The time course of loss of response in the Y fibres is similar whether the loss is due to a pressure block or to enucleation, suggesting that the pressure block as used by us causes a disruption of the axon. If the pressure is great enough to block part of the t2 response (X fibres) there is also a similarity in time course of loss of response to that following enucleation. Both for the enucleated and the pressure-blocked cat the t2 response fails about 1 day before the t1 response. This is in apparent disagreement with the morphological findings in the literature, confirmed here, indicating an earlier degeneration of the larger fibres. The post-synaptic response in the lateral geniculate nucleus to the t1 input (the r1 response) also fails about 1 day before the t1 response. In the visual cortex the loss of the r1 response reveals more clearly than is normally possible an r2 response, the response of the X optic radiation fibres. The response in the optic nerve or tract to a bright flash of light is dominated by the response of the Y fibres. When these are blocked the response is greatly reduced. Images Plate 1 PMID:3795079

  19. Interventional multispectral photoacoustic imaging with a clinical linear array ultrasound probe for guiding nerve blocks

    NASA Astrophysics Data System (ADS)

    Xia, Wenfeng; West, Simeon J.; Nikitichev, Daniil I.; Ourselin, Sebastien; Beard, Paul C.; Desjardins, Adrien E.

    2016-03-01

    Accurate identification of tissue structures such as nerves and blood vessels is critically important for interventional procedures such as nerve blocks. Ultrasound imaging is widely used as a guidance modality to visualize anatomical structures in real-time. However, identification of nerves and small blood vessels can be very challenging, and accidental intra-neural or intra-vascular injections can result in significant complications. Multi-spectral photoacoustic imaging can provide high sensitivity and specificity for discriminating hemoglobin- and lipid-rich tissues. However, conventional surface-illumination-based photoacoustic systems suffer from limited sensitivity at large depths. In this study, for the first time, an interventional multispectral photoacoustic imaging (IMPA) system was used to image nerves in a swine model in vivo. Pulsed excitation light with wavelengths in the ranges of 750 - 900 nm and 1150 - 1300 nm was delivered inside the body through an optical fiber positioned within the cannula of an injection needle. Ultrasound waves were received at the tissue surface using a clinical linear array imaging probe. Co-registered B-mode ultrasound images were acquired using the same imaging probe. Nerve identification was performed using a combination of B-mode ultrasound imaging and electrical stimulation. Using a linear model, spectral-unmixing of the photoacoustic data was performed to provide image contrast for oxygenated and de-oxygenated hemoglobin, water and lipids. Good correspondence between a known nerve location and a lipid-rich region in the photoacoustic images was observed. The results indicate that IMPA is a promising modality for guiding nerve blocks and other interventional procedures. Challenges involved with clinical translation are discussed.

  20. Pudendal Nerve Stimulation and Block by a Wireless Controlled Implantable Stimulator in Cats

    PubMed Central

    Yang, Guangning; Wang, Jicheng; Shen, Bing; Roppolo, James R.; de Groat, William C.; Tai, Changfeng

    2014-01-01

    Objective To determine the functionality of a wireless controlled implantable stimulator designed for stimulation and block of the pudendal nerve. Materials and Methods In 5 cats under α-chloralose anesthesia, the stimulator was implanted underneath the skin on the left side in the lower back along the sacral spine. Two tripolar cuff electrodes were implanted bilaterally on the pudendal nerves in addition to one bipolar cuff electrode that was implanted on the left side central to the tripolar cuff electrode. The stimulator provided high frequency (5-20 kHz) biphasic stimulation waveforms to the two tripolar electrodes and low frequency (1-100 Hz) rectangular pulses to the bipolar electrode. Bladder and urethral pressures were measured to determine the effects of pudendal nerve stimulation (PNS) or block. Results The maximal (70-100 cmH2O) urethral pressure generated by 20 Hz PNS applied via the bipolar electrode was completely eliminated by the pudendal nerve block induced by the high frequency stimulation (6-15 kHz, 6-10 V) applied via the two tripolar electrodes. In a partially filled bladder 20-30 Hz PNS (2-8 V, 0.2 ms) but not 5 Hz stimulation applied via the bipolar electrode elicited a large sustained bladder contraction (45.9±13.4 to 52.0±22 cmH2O). During cystometry, the 5 Hz PNS significantly (P<0.05) increased bladder capacity to 176.5±27.1% of control capacity. Conclusions The wireless controlled implantable stimulator successfully generated the required waveforms for stimulation and block of pudendal nerve, which will be useful for restoring bladder functions after spinal cord injury (SCI). PMID:24320615

  1. Peripheral nerve blocks on the upper extremity: Technique of landmark-based and ultrasound-guided approaches.

    PubMed

    Steinfeldt, T; Volk, T; Kessler, P; Vicent, O; Wulf, H; Gottschalk, A; Lange, M; Schwartzkopf, P; Hüttemann, E; Tessmann, R; Marx, A; Souquet, J; Häger, D; Nagel, W; Biscoping, J; Schwemmer, U

    2015-11-01

    The German Society of Anaesthesiology and Intensive Care Medicine (Deutsche Gesellschaft für Anästhesiologie und Intensivmedizin, DGAI) established an expert panel to develop preliminary recommendations for the application of peripheral nerve blocks on the upper extremity. The present recommendations state in different variations how ultrasound and/or electrical nerve stimulation guided nerve blocks should be performed. The description of each procedure is rather a recommendation than a guideline. The anaesthesiologist should select the variation of block which provides the highest grade of safety according to his individual opportunities. The first section comprises recommendations regarding dosages of local anaesthetics, general indications and contraindications for peripheral nerve blocks and informations about complications. In the following sections most common blocks techniques on the upper extremity are described. PMID:26408023

  2. Pain management: setting up a nurse-led femoral nerve block service.

    PubMed

    Layzell, Mandy

    Managing pain following a fractured neck of femur is challenging for a number of reasons. This group of patients are typically older people and frail with multiple co-morbidities and are often on numerous medications. In addition to a hip fracture, they commonly present with acute medical problems. Fractures cause significant pain, which can be difficult to manage safely and effectively with the traditional analgesics. A femoral nerve block has been shown to be a safe and effective preoperative intervention for managing pain in this patient group while they wait for surgery. This article describes how an acute pain team have developed protocols and training to establish a nurse-led service for providing preoperative femoral nerve blocks to patients with fractured neck of femur. PMID:17851357

  3. Needle stylet with integrated optical fibers for spectroscopic contrast during peripheral nerve blocks

    NASA Astrophysics Data System (ADS)

    Desjardins, Adrien E.; van der Voort, Marjolein; Roggeveen, Stefan; Lucassen, Gerald; Bierhoff, Walter; Hendriks, Benno H. W.; Brynolf, Marcus; Holmström, Björn

    2011-07-01

    The effectiveness of peripheral nerve blocks is highly dependent on the accuracy at which the needle tip is navigated to the target injection site. Even when electrical stimulation is utilized in combination with ultrasound guidance, determining the proximity of the needle tip to the target region close to the nerve can be challenging. Optical reflectance spectroscopy could provide additional information about tissues that is complementary to these navigation methods. We demonstrate a novel needle stylet for acquiring spectra from tissue at the tip of a commercial 20-gauge needle. The stylet has integrated optical fibers that deliver broadband light to tissue and receive scattered light. Two spectrometers resolve the light that is received from tissue across the wavelength range of 500-1600 nm. In our pilot study, measurements are acquired from a postmortem dissection of the brachial plexus of a swine. Clear differences are observed between spectra acquired from nerves and those acquired from adjacent tissue structures. We conclude that spectra acquired with the stylet have the potential to increase the accuracy with which peripheral nerve blocks are performed.

  4. Transition from nerve blocks to periarticular injections and emerging techniques in total joint arthroplasty.

    PubMed

    Springer, Bryan D

    2014-10-01

    The emergence of procedure-specific multimodal pain management regimens that provide effective control of postoperative pain, while markedly reducing the amount of opioid medication required, has been one of the most important advances in hip and knee replacement in recent years. When peripheral nerve blockade first became widely available for inclusion in multimodal regimens, it was viewed as a revolution in the management of postoperative pain. This approach, however, is costly and has some important limitations, including an increased incidence of falls. For many patients, peripheral nerve blocks can now be replaced by a periarticular injection with EXPAREL® (bupivacaine liposome injectable suspension), an extended-release anesthetic infiltrated by the surgeon as part of a multimodal pain regimen. EXPAREL® offers some important clinical and administrative benefits over nerve blocks. Preliminary data from a pilot study comparing the relative effectiveness of EXPAREL® versus sciatic nerve blockade has shown a noticeable reduction in average pain scores at rest with EXPAREL® following both hip and knee arthroplasty, as well as a reduction in the 6- to 12-hour pain score following hip arthroplasty. There was also a significant reduction in opioid use with EXPAREL®, as well as a $411 reduction in the cost of total knee arthroplasty and a $348 reduction in the cost of total hip arthroplasty.

  5. Anterior and middle superior alveolar nerve block for anesthesia of maxillary teeth using conventional syringe

    PubMed Central

    Velasco, Ignacio; Soto, Reinaldo

    2012-01-01

    Background: Dental procedures in the maxilla typically require multiple injections and may inadvertently anesthetize facial structures and affect the smile line. To minimize these inconveniences and reduce the number of total injections, a relatively new injection technique has been proposed for maxillary procedures, the anterior and middle superior alveolar (AMSA) nerve block, which achieves pulpal anesthesia from the central incisor to second premolar through palatal approach with a single injection. The purpose of this article is to provide background information on the anterior and middle superior alveolar nerve block and demonstrate its success rates of pulpal anesthesia using the conventional syringe. Materials and Methods: Thirty Caucasian patients (16 men and 14 women) with an average age of 22 years-old, belonging to the School of Dentistry of Los Andes University, were selected. All the patients received an AMSA nerve block on one side of the maxilla using the conventional syringe, 1 ml of lidocaine 2% with epinephrine 1:100.000 was injected to all the patients. Results: The AMSA nerve block obtained a 66% anesthetic success in the second premolar, 40% in the first premolar, 60% in the canine, 23.3% in the lateral incisor, and 16.7% in the central incisor. Conclusions: Because of the unpredictable anesthetic success of the experimental teeth and variable anesthesia duration, the technique is disadvantageous for clinical application as the first choice, counting with other techniques that have greater efficacy in the maxilla. Although, anesthetizing the teeth without numbing the facial muscles may be useful in restorative dentistry. PMID:23559916

  6. Curative effect research on curing intercostal neuralgia through paravertebral nerve block combined with pregabalin.

    PubMed

    Xiao, Peng; Zhu, Xu; Wu, Xuejian

    2014-09-01

    This paper aimed to discuss the curative effect and safety of curing intercostal neuralgia through paravertebral nerve block combined with pregabalin. 90 cases of patients diagnosed as intercostal neuralgia were taken as research object. Random number method was used to divide the patients that is conforming to the inclusion criteria and exclusion criteria into 3 groups. 30 cases was in group A (oral lyrica), 30 cases was in group B (paravertebral block only) and 30 cases was in group C (paravertebral block combined with pregabalin). The clinical effect and safety of three groups was compared. The result showed that: visual analogue scale (VAS) and quality of sleep (QS) of three groups of patients after treatment all decreased obviously; group A had slow work, large amount of dosage and many adverse effects; group B had quick work, but the improvement on pain and sleep was not satisfactory; the curative effect of group C was higher than group A and B (p<0.05); 3 groups all had adverse effect, among which group C had the least adverse effect. It can be concluded that paravertebral nerve block combined with pregabalin for curing intercostal neuralgia was superior than single use of pregabalin or paravertebral block and that is worth to promote.

  7. Effects of ramped amplitude waveforms on the onset response of high-frequency mammalian nerve block

    NASA Astrophysics Data System (ADS)

    Miles, J. D.; Kilgore, K. L.; Bhadra, N.; Lahowetz, E. A.

    2007-12-01

    Though high-frequency alternating current (HFAC) can block nerve conduction, the block is invariably preceded by an onset response which is a period of repetitive nerve firing. We tested the hypothesis that slowly ramping up the amplitude of the HFAC waveform could produce block without this initial onset response. Computer simulations were performed, using the McIntyre-Richardson-Grill (MRG) model of myelinated mammalian axon. A ramped-amplitude HFAC was applied to axons of diameters ranging from 7.3 µm to 16 µm and at frequencies ranging from 3125 Hz to 40 kHz. The ramped-amplitude HFAC was also investigated in vivo in preparations of rat sciatic nerve. Sinusoidal voltage-regulated waveforms, at frequencies between 10 kHz and 30 kHz, were applied with initial amplitudes of 0 V, linearly increasing with time to 10 V. Ramp durations ranged from 0 s to 60 s. In both the MRG model simulations and the experiments, ramping the HFAC waveform did not eliminate the onset response. In the rat experiments, the peak amplitude of the onset response was lessened by ramping the amplitude, but both the onset response duration and the amount of onset activity as measured by the force-time integral were increased.

  8. The Effect of 2 Injection Speeds on Local Anesthetic Discomfort During Inferior Alveolar Nerve Blocks

    PubMed Central

    de Souza Melo, Marcelo Rodrigo; Sabey, Mark Jon Santana; Lima, Carla Juliane; de Almeida Souza, Liane Maciel; Groppo, Francisco Carlos

    2015-01-01

    This randomized double-blind crossover trial investigated the discomfort associated with 2 injection speeds, low (60 seconds) and slow (100 seconds), during inferior alveolar nerve block by using 1.8 mL of 2% lidocaine with 1 : 100,000 epinephrine. Three phases were considered: (a) mucosa perforation, (b) needle insertion, and (c) solution injection. Thirty-two healthy adult volunteers needing bilateral inferior alveolar nerve blocks at least 1 week apart were enrolled in the present study. The anesthetic procedure discomfort was recorded by volunteers on a 10-cm visual analog scale in each phase for both injection speeds. Comparison between the 2 anesthesia speeds in each phase was performed by paired t test. Results showed no statistically significant difference between injection speeds regarding perforation (P = .1016), needle placement (P = .0584), or speed injection (P = .1806). The discomfort in all phases was considered low. We concluded that the 2 injection speeds tested did not affect the volunteers' pain perception during inferior alveolar nerve blocks. PMID:26398126

  9. Antiinflammatory effect of peripheral nerve blocks after knee surgery: clinical and biologic evaluation

    PubMed Central

    Martin, Frédéric; Martinez, Valéria; Mazoit, Jean Xavier; Bouhassira, Didier; Cherif, Kamel; Gentili, Marc Edouard; Piriou, Philippe; Chauvin, Marcel; Fletcher, Dominique

    2008-01-01

    Background Nerve blocks provide analgesia after surgery. We tested whether they have anti-inflammatory effects. Methods Patient had combined sciatic (single shot) and continuous femoral block (48 hours) (block group) or morphine patient-controlled analgesia (PCA group) after total knee arthroplasty. Pain at rest and upon movement was monitored at one (D1), four (D4) and seven days (D7) and one (M1) and three months (M3) after surgery. Knee inflammation was evaluated (skin temperature, knee circumference) before surgery and at D1, D4, D7, M1 and M3. Plasma cytokine concentrations (IL6, IL1β, TNF, IL10, sTNF-R1) were measured before surgery, then at four hours, D1, D4 and D7 after surgery. Capsule and synovial membrane cytokines were measured (IL6, TNF, IL1, IL10). Knee flexion was evaluated before surgery and at D1, D4, D7, M1 and M3. We monitored morphine use and recovery time to autonomy. Results Pain at rest and upon movement was lower in the block group than in PCA patients between D1 and D7 (Anova; P<0.005). Knee flexion was improved in the block group for D1 to M1 (Anova; p<0.0001). Block group patients recovered non-assisted mobilization (t test; p=0.04) and toilet use (t test; p=0.03) more rapidly. Knee circumference and skin temperature were lower in the block group between D1 and D7 (Anova; p<0.05). Synovial membrane IL1 (p<0.05) and IL10 (p<0.01) increased and plasma IL6 and sTNF-R1 peaked at 24 hours, with no difference between groups. Conclusion Nerve blocks inhibited clinical inflammation after total knee arthroplasty with no change in tissue and plasma cytokine concentrations. PMID:18719447

  10. A role for nociceptive, myelinated nerve fibers in itch sensation.

    PubMed

    Ringkamp, Matthias; Schepers, Raf J; Shimada, Steven G; Johanek, Lisa M; Hartke, Timothy V; Borzan, Jasenka; Shim, Beom; LaMotte, Robert H; Meyer, Richard A

    2011-10-19

    Despite its clinical importance, the underlying neural mechanisms of itch sensation are poorly understood. In many diseases, pruritus is not effectively treated with antihistamines, indicating the involvement of nonhistaminergic mechanisms. To investigate the role of small myelinated afferents in nonhistaminergic itch, we tested, in psychophysical studies in humans, the effect of a differential nerve block on itch produced by intradermal insertion of spicules from the pods of a cowhage plant (Mucuna pruriens). Electrophysiological experiments in anesthetized monkey were used to investigate the responsiveness of cutaneous, nociceptive, myelinated afferents to different chemical stimuli (cowhage spicules, histamine, capsaicin). Our results provide several lines of evidence for an important role of myelinated fibers in cowhage-induced itch: (1) a selective conduction block in myelinated fibers substantially reduces itch in a subgroup of subjects with A-fiber-dominated itch, (2) the time course of itch sensation differs between subjects with A-fiber- versus C-fiber-dominated itch, (3) cowhage activates a subpopulation of myelinated and unmyelinated afferents in monkey, (4) the time course of the response to cowhage is different in myelinated and unmyelinated fibers, (5) the time of peak itch sensation for subjects with A-fiber-dominated itch matches the time for peak response in myelinated fibers, and (6) the time for peak itch sensation for subjects with C-fiber-dominated itch matches the time for the peak response in unmyelinated fibers. These findings demonstrate that activity in nociceptive, myelinated afferents contributes to cowhage-induced sensations, and that nonhistaminergic itch is mediated through activity in both unmyelinated and myelinated afferents. PMID:22016517

  11. Conduction block of mammalian myelinated nerve by local cooling to 15-30°C after a brief heating.

    PubMed

    Zhang, Zhaocun; Lyon, Timothy D; Kadow, Brian T; Shen, Bing; Wang, Jicheng; Lee, Andy; Kang, Audry; Roppolo, James R; de Groat, William C; Tai, Changfeng

    2016-03-01

    This study aimed at understanding thermal effects on nerve conduction and developing new methods to produce a reversible thermal block of axonal conduction in mammalian myelinated nerves. In 13 cats under α-chloralose anesthesia, conduction block of pudendal nerves (n = 20) by cooling (5-30°C) or heating (42-54°C) a small segment (9 mm) of the nerve was monitored by the urethral striated muscle contractions and increases in intraurethral pressure induced by intermittent (5 s on and 20 s off) electrical stimulation (50 Hz, 0.2 ms) of the nerve. Cold block was observed at 5-15°C while heat block occurred at 50-54°C. A complete cold block up to 10 min was fully reversible, but a complete heat block was only reversible when the heating duration was less than 1.3 ± 0.1 min. A brief (<1 min) reversible complete heat block at 50-54°C or 15 min of nonblock mild heating at 46-48°C significantly increased the cold block temperature to 15-30°C. The effect of heating on cold block fully reversed within ∼40 min. This study discovered a novel method to block mammalian myelinated nerves at 15-30°C, providing the possibility to develop an implantable device to block axonal conduction and treat many chronic disorders. The effect of heating on cold block is of considerable interest because it raises many basic scientific questions that may help reveal the mechanisms underlying cold or heat block of axonal conduction. PMID:26740534

  12. The impact of peripheral nerve blocks on perioperative outcome in hip and knee arthroplasty-a population-based study.

    PubMed

    Memtsoudis, Stavros G; Poeran, Jashvant; Cozowicz, Crispiana; Zubizarreta, Nicole; Ozbek, Umut; Mazumdar, Madhu

    2016-10-01

    The role of anesthesia techniques on perioperative outcomes on a population level has recently gained widespread interest. Although mainly neuraxial vs general anesthesia has been addressed, population-level data on the impact of peripheral nerve blocks (PNBs) are still lacking. Therefore, we investigated the association between PNB use and outcomes using retrospective data on 1,062,152 recipients of hip and knee arthroplasties (total hip arthroplasty [THA]/total knee arthroplasty [TKA]) from the national Premier Perspective database (2006-2013). Multilevel multivariable logistic regression models measured associations between PNB use and outcomes. Complications included cardiac, pulmonary, gastrointestinal and renal complications, cerebrovascular events, infections, wound complications, thromboembolic complications, inpatient falls, and mortality. Resource utilization variables included blood transfusions, intensive care unit admissions, opioid consumption, cost, and length of stay. Overall, 12.5% of patients received a PNB, with an increase over time particularly among TKAs. Peripheral nerve block use was associated with lower odds for most adverse outcomes mainly among patients with THA. Notable beneficial effects were seen for wound complications (odds ratio 0.60 [95% confidence interval, 0.49-0.74]) among THA recipients and pulmonary complications (odds ratio 0.83 [95% confidence interval, 0.72-0.94]) in patients with TKA. Peripheral nerve block use was significantly (P < 0.0001) associated with a -16.2% and -12.7% reduction in opioid consumption for patients with THA and TKA, respectively. In conclusion, our results indicate that PNBs might be associated with superior perioperative population-level outcomes. In light of the inability to establish a causal relationship and the presence of residual confounding, we strongly advocate for further prospective investigation, ideally in multicenter, randomized trials, to establish the potential impact of PNBs on

  13. Nerve Blocks

    MedlinePlus

    ... Comment: E-mail: Area code: Phone no: Images × Image Gallery Radiologist and patient consultation. View full size with caption Related Articles and Media Computed Tomography (CT) - Body Radiation Dose in X-Ray and CT Exams ...

  14. Addition of Dexamethasone and Buprenorphine to Bupivacaine Sciatic Nerve Block: A Randomized, Controlled Trial

    PubMed Central

    YaDeau, Jacques T.; Paroli, Leonardo; Fields, Kara G.; Kahn, Richard L.; LaSala, Vincent R.; Jules-Elysee, Kethy M.; Kim, David H.; Haskins, Stephen C.; Hedden, Jacob; Goon, Amanda; Roberts, Matthew M.; Levine, David S.

    2015-01-01

    Background and Objectives Sciatic nerve block provides analgesia after foot and ankle surgery, but block duration may be insufficient. We hypothesized that perineural dexamethasone and buprenorphine would reduce pain scores at 24 hours. Methods Ninety patients received ultrasound-guided sciatic (25 mL 0.25% bupivacaine) and adductor canal (10 mL 0.25% bupivacaine) blockade, with random assignment into 3 groups (30 patients per group): control blocks + intravenous dexamethasone (4 mg) (control); control blocks + intravenous buprenorphine (150 mcg) + intravenous dexamethasone (intravenous buprenorphine); nerve blocks containing buprenorphine + dexamethasone (perineural). Patients received mepivacaine neuraxial anesthesia and postoperative oxycodone / acetaminophen, meloxicam, pregabalin, and ondansetron. Patients and assessors were blinded to group assignment. The primary outcome was pain with movement at 24 hours. Results There was no difference in pain with movement at 24 hours (median score 0). However, the perineural group had longer block duration vs control (45.6 vs 30.0 hr). Perineural patients had lower scores for “worst pain” vs control (median 0 vs 2). Both intravenous buprenorphine and perineural groups were less likely to use opioids on the day after surgery, vs control (28.6%, 28.6%, 60.7%, respectively). Nausea after intravenous buprenorphine (but not perineural buprenorphine) was severe, frequent, and bothersome. Conclusions Pain scores were very low at 24 hours after surgery in the context of multimodal analgesia and were not improved by additives. However, perineural buprenorphine and dexamethasone prolonged block duration, reduced the worst pain experienced, and reduced opioid use. Intravenous buprenorphine caused troubling nausea and vomiting. Future research is needed to confirm and extend these observations. PMID:25974277

  15. Scaffolds from alternating block polyurethanes of poly(ɛ-caprolactone) and poly(ethylene glycol) with stimulation and guidance of nerve growth and better nerve repair than autograft.

    PubMed

    Niu, Yuqing; Li, Linjing; Chen, Kevin C; Chen, Feiran; Liu, Xiangyu; Ye, Jianfu; Li, Wei; Xu, Kaitian

    2015-07-01

    Nerve repair scaffolds from novel alternating block polyurethanes (PUCL-alt-PEG) based on PCL and PEG without additional growth factors or proteins were prepared by a particle leaching method. The scaffolds have pore size 10-20 µm and porosity 92%. Mechanical tests showed that the polyurethane scaffolds have maximum loads of 5.97 ± 0.35 N and maximal stresses of 8.84 ± 0.5 MPa. Histocompatiblity of the nerve repair scaffolds was tested in a SD rat model for peripheral nerve defect treatment. Two types of treatments including PUCL-alt-PEG scaffolds and autografts were compared in rat model. After 32 weeks, bridging of a 12 mm defect gap by the regenerated nerve was observed in all rats. The nerve regeneration was systematically characterized by sciatic function index (SFI), electrophysiology, histological assessment including HE staining, immunohistochemistry, ammonia sliver staining, Masson's trichrome staining and TEM observation. Results revealed that nerve repair scaffolds from PUCL-alt-PEG exhibit better regeneration effects compared to autografts. Electrophysiological recovery was seen in 90% and 87% of rats in PUCL-alt-PEG and autograft groups respectively. Biodegradation in vitro and in vivo shows good degradation match of PUCL-alt-PEG scaffolds with nerve regeneration. It demonstrates that plain nerve repair scaffolds from PUCL-alt-PEG biomaterials can achieve peripheral nerve regeneration satisfactorily.

  16. Role of glutamatergic system in nerve agent intoxication

    SciTech Connect

    Blanchet, G.; Lallement, G.; Carpentier, P.; De Groot, D.; Bodjarian, N.

    1993-05-13

    Our recent studies concerning soman-induced seizures mechanisms and subsequent brain damage are reviewed. (1) Seizure activity was associated with transient increases of extracellular concentrations of acetylcholine (ACh) and with long-lasting releases of glutamate (Glu) in all limbic areas studied. (2) Preventive intraseptal application of atropine abolished the hippocampal increases of extracellular AChi and Glu indicating a key role of septum in triggering seizure activity. (3) Early increases of hippocampal AMPA receptor binding occurred before activation of NMDA receptors. (4) Pretreatment with NBQX, an antagonist of AMPA receptor, prevented convulsions and brain damage even without atropine. In the same conditions, no protection was afforded by TCP, a non-competitive antagonist of the NMDA receptor. (5) On the contrary, in the presence of pyridostigmine and atropine, TCP blocked the seizures induced by 2 x LD50 of soman. The anticonvulsant potency of TCP was particularly obvious when administered curatively. (6) Mossy fibers sprouting takes place in the supragranular-molecular layers of rat hippocampus long after brain injury associated with abnormal neuronal excitability. (7) Altogether, it appears that an AMPA component is involved in combination with cholinergic mechanisms in initiating seizures. A subsequent and long-lasting recruitment of NMDA receptors is then essential in sustaining the seizures. New anticonvulsant and neuroprotective approaches using Glu antagonists against nerve agents intoxication are discussed.

  17. Transversus Abdominis Plane Versus Ilioinguinal and Iliohypogastric Nerve Blocks for Analgesia Following Open Inguinal Herniorrhaphy*

    PubMed Central

    Stav, Anatoli; Reytman, Leonid; Stav, Michael-Yohay; Troitsa, Anton; Kirshon, Mark; Alfici, Ricardo; Dudkiewicz, Mickey; Sternberg, Ahud

    2016-01-01

    Objectives We hypothesized that preoperative (pre-op) ultrasound (US)-guided posterior transversus abdominis plane block (TAP) and US-guided ilioinguinal and iliohypogastric nerve block (ILI+IHG) will produce a comparable analgesia after Lichtenstein patch tension-free method of open inguinal hernia repair in adult men. The genital branch of the genitofemoral nerve will be blocked separately. Methods This is a prospective, randomized, controlled, and observer-blinded clinical study. A total of 166 adult men were randomly assigned to one of three groups: a pre-op TAP group, a pre-op ILI+IHG group, and a control group. An intraoperative block of the genital branch of the genitofemoral nerve was performed in all patients in all three groups, followed by postoperative patient-controlled intravenous analgesia with morphine. The pain intensity and morphine consumption immediately after surgery and during the 24 hours after surgery were compared between the groups. Results A total of 149 patients completed the study protocol. The intensity of pain immediately after surgery and morphine consumption were similar in the two “block” groups; however, they were significantly decreased compared with the control group. During the 24 hours after surgery, morphine consumption in the ILI+IHG group decreased compared with the TAP group, as well as in each “block” group versus the control group. Twenty-four hours after surgery, all evaluated parameters were similar. Conclusion Ultrasound-guided ILI+IHG provided better pain control than US-guided posterior TAP following the Lichtenstein patch tension-free method of open inguinal hernia repair in men during 24 hours after surgery. (ClinicalTrials.gov number: NCT01429480.) PMID:27487311

  18. Transient Heat Hyperalgesia During Resolution of Ropivacaine Sciatic Nerve Block in the Rat

    PubMed Central

    Kolarczyk, Lavinia M.; Williams, Brian A.

    2011-01-01

    Background Preliminary studies using perineural sciatic ropivacaine in rat demonstrated unexpected heat hyperalgesia after block resolution. To better characterize the time course relative to mechanical anesthesia-analgesia, we tested the hypothesis that ropivacaine 0.5% leads to transient heat hyperalgesia in rat independent of mechanical nociception. We also evaluated functional toxicity (e.g., long-term hyperalgesia and/or tactile allodynia 2 weeks post-injection). Methods Under surgical exposure, left sciatic nerve block was performed in 2 groups of adult male rats – ropivacaine (200 μL, 5 mg/mL, n=14) versus vehicle (n=11). The efficacy and duration of block was assessed with serial heat, mechanical (Randall-Selitto testing), and tactile (von Frey-like monofilaments) tests; motor-proprioceptive (rotarod) and sedation tests were employed 1 hr and 7 hr post-injection. The presence of nerve injury was assessed by repeating the heat, tactile, and motor tests 12–14 days post-injection. Results Ropivacaine-induced anesthesia was fully manifest at 1 hr post-injection. At 3 hr post-injection, heat hypersensitivity was present in the setting of resolved mechanical analgesia. All behavioral measures returned to baseline by 2 wk post-injection. There was no evidence of (i) behavioral sedation, (ii) persistent changes in heat or mechanical sensitivity, or (iii) persistent changes in proprioceptive-motor function at 12–14 days post-injection. Conclusions Ropivacaine 0.5% induces transient heat hyperalgesia in the setting of resolved mechanical analgesia, further suggestive of modality and/or nociceptive fiber specificity. Whether this finding partially translates to “rebound pain” after patients’ nerve blocks wear off requires further study. PMID:21451438

  19. [Relevance of nerve blocks in treating and diagnosing low back pain--is the quality decisive?].

    PubMed

    Hildebrandt, J

    2001-12-01

    Diagnostic nerve blocks: The popularity of neural blockade as a diagnostic tool in painful conditions, especially in the spine, is due to features like the unspecific character of spinal pain, the irrelevance of radiological findings and the purely subjective character of pain. It is said that apart from specific causes of pain and clear radicular involvement with obvious neurological deficits and corresponding findings of a prolapsed disc in MRI or CT pictures, a diagnosis of the anatomical cause of the pain can only be established if invasive tests are used [5]. These include zygapophyseal joint blocks, sacroiliacal joint blocks, disc stimulation and nerve root blocks. Under controlled conditions, it has been shown that among patients with chronic nonradicular low back pain, some 10-15% have zygapophyseal joint pain [58], some 15-20% have sacroiliacal joint pain [36, 59] and 40% have pain from internal disc disruption [60]. The diagnostic use of neural blockade rests on three premises. First, pathology causing pain is located in an exact peripheral location, and impulses from this site travel via a unique and consistent neural root. Second, injection of local aneasthetic totally abolishes sensory function of intended nerves and does not affect other nerves. Third, relief of pain after local anaesthetic block is attributable solely to block of the target afferent neural pathway. The validity of these assumptions is limited by complexities of anatomy, physiology, and psychology of pain perception and the effect of local anaesthetics on impulse conduction [28]. Facet joints: The prevalence of zygapophyseal joint pain among patients with low back pain seems to be between 15% and 40% [62], but apparently only 7% of patients have pure facet pain [8, 29]. Facet blockade is achieved either by injection of local anaesthetic into the joint space or around the medial branches of the posterior medial rami of the spinal nerves that innervate the joint. There are several

  20. Repeatable and adjustable on-demand sciatic nerve block with phototriggerable liposomes.

    PubMed

    Rwei, Alina Y; Lee, Jung-Jae; Zhan, Changyou; Liu, Qian; Ok, Meryem T; Shankarappa, Sahadev A; Langer, Robert; Kohane, Daniel S

    2015-12-22

    Pain management would be greatly enhanced by a formulation that would provide local anesthesia at the time desired by patients and with the desired intensity and duration. To this end, we have developed near-infrared (NIR) light-triggered liposomes to provide on-demand adjustable local anesthesia. The liposomes contained tetrodotoxin (TTX), which has ultrapotent local anesthetic properties. They were made photo-labile by encapsulation of a NIR-triggerable photosensitizer; irradiation at 730 nm led to peroxidation of liposomal lipids, allowing drug release. In vitro, 5.6% of TTX was released upon NIR irradiation, which could be repeated a second time. The formulations were not cytotoxic in cell culture. In vivo, injection of liposomes containing TTX and the photosensitizer caused an initial nerve block lasting 13.5 ± 3.1 h. Additional periods of nerve block could be induced by irradiation at 730 nm. The timing, intensity, and duration of nerve blockade could be controlled by adjusting the timing, irradiance, and duration of irradiation. Tissue reaction to this formulation and the associated irradiation was benign. PMID:26644576

  1. Repeatable and adjustable on-demand sciatic nerve block with phototriggerable liposomes

    PubMed Central

    Rwei, Alina Y.; Lee, Jung-Jae; Zhan, Changyou; Liu, Qian; Ok, Meryem T.; Shankarappa, Sahadev A.; Langer, Robert; Kohane, Daniel S.

    2015-01-01

    Pain management would be greatly enhanced by a formulation that would provide local anesthesia at the time desired by patients and with the desired intensity and duration. To this end, we have developed near-infrared (NIR) light-triggered liposomes to provide on-demand adjustable local anesthesia. The liposomes contained tetrodotoxin (TTX), which has ultrapotent local anesthetic properties. They were made photo-labile by encapsulation of a NIR-triggerable photosensitizer; irradiation at 730 nm led to peroxidation of liposomal lipids, allowing drug release. In vitro, 5.6% of TTX was released upon NIR irradiation, which could be repeated a second time. The formulations were not cytotoxic in cell culture. In vivo, injection of liposomes containing TTX and the photosensitizer caused an initial nerve block lasting 13.5 ± 3.1 h. Additional periods of nerve block could be induced by irradiation at 730 nm. The timing, intensity, and duration of nerve blockade could be controlled by adjusting the timing, irradiance, and duration of irradiation. Tissue reaction to this formulation and the associated irradiation was benign. PMID:26644576

  2. The Role of 5-HT3 Receptors in Signaling from Taste Buds to Nerves

    PubMed Central

    Vandenbeuch, Aurelie; Voigt, Anja; Meyerhof, Wolfgang; Kinnamon, Sue C.; Finger, Thomas E.

    2015-01-01

    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-HT3A 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-HT3A 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. SIGNIFICANCE STATEMENT Historically, serotonin (5-hydroxytryptamine; 5-HT) has been described as a candidate neurotransmitter in the gustatory system and recent studies show that type III taste receptor cells release 5-HT in response to various taste stimuli. In the present study, we demonstrate that a subset of gustatory sensory neurons express functional

  3. Effect of Preoperative Nerve Block on Postthyroidectomy Headache and Cervical Pain: A Randomized Prospective Study

    PubMed Central

    Barua, Sunil Malla Bujar; Kishore, Kamal; Mishra, Saroj Kanta; Agarwal, Gaurav; Agarwal, Amit; Verma, Ashok Kumar

    2016-01-01

    The aim of the current study was to investigate the efficacy of greater occipital nerve (GON) block and bilateral superficial cervical plexuses (BSCP) blocks in alleviating postoperative occipital headache and posterior neck pain after thyroidectomy. This randomized prospective study consisted of 75 women undergoing total thyroidectomy. Patients were randomized into three groups: Group I (n = 25): patients receiving GON, Group II (n = 25): patients receiving bilateral (BSCP) blocks, and Group III (n = 25): patients receiving no block. Assessment of occipital headache, posterior neck, and incision site pains was made at 12 hours and 24 hours after extubation by Visual Analogue Scale (VAS). In comparison to Group III significantly fewer patients in Groups I and II experienced occipital headache at 12 (p = 0.006) and 24 hours (p = 0.005) and also posterior neck pain at 24 hours (p = 0.003). Mean VAS scores at 12 and 24 hours for occipital headache (p = 0.003 and p = 0.041) and posterior neck pain (p = 0.015 and p = 0.008) were significantly lower in Group I. The differences between Groups II and III were not significant except for the occipital headache at 12 hours. The efficacy of GON block is superior to BSCP blocks in alleviating postthyroidectomy occipital headache and posterior cervical pain. PMID:27034886

  4. Comparison of Transcutaneous Electrical Nerve Stimulation and Parasternal Block for Postoperative Pain Management after Cardiac Surgery.

    PubMed

    Ozturk, Nilgun Kavrut; Baki, Elif Dogan; Kavakli, Ali Sait; Sahin, Ayca Sultan; Ayoglu, Raif Umut; Karaveli, Arzu; Emmiler, Mustafa; Inanoglu, Kerem; Karsli, Bilge

    2016-01-01

    Background. Parasternal block and transcutaneous electrical nerve stimulation (TENS) have been demonstrated to produce effective analgesia and reduce postoperative opioid requirements in patients undergoing cardiac surgery. Objectives. To compare the effectiveness of TENS and parasternal block on early postoperative pain after cardiac surgery. Methods. One hundred twenty patients undergoing cardiac surgery were enrolled in the present randomized, controlled prospective study. Patients were assigned to three treatment groups: parasternal block, intermittent TENS application, or a control group. Results. Pain scores recorded 4 h, 5 h, 6 h, 7 h, and 8 h postoperatively were lower in the parasternal block group than in the TENS and control groups. Total morphine consumption was also lower in the parasternal block group than in the TENS and control groups. It was also significantly lower in the TENS group than in the control group. There were no statistical differences among the groups regarding the extubation time, rescue analgesic medication, length of intensive care unit stay, or length of hospital stay. Conclusions. Parasternal block was more effective than TENS in the management of early postoperative pain and the reduction of opioid requirements in patients who underwent cardiac surgery through median sternotomy. This trial is registered with Clinicaltrials.gov number NCT02725229. PMID:27445610

  5. Teaching alternatives to the standard inferior alveolar nerve block in dental education: outcomes in clinical practice.

    PubMed

    Johnson, Thomas M; Badovinac, Rachel; Shaefer, Jeffry

    2007-09-01

    Surveys were sent to Harvard School of Dental Medicine students and graduates from the classes of 2000 through 2006 to determine their current primary means of achieving mandibular anesthesia. Orthodontists and orthodontic residents were excluded. All subjects received clinical training in the conventional inferior alveolar nerve block and two alternative techniques (the Akinosi mandibular block and the Gow-Gates mandibular block) during their predoctoral dental education. This study tests the hypothesis that students and graduates who received training in the conventional inferior alveolar nerve block, the Akinosi mandibular block, and the Gow-Gates mandibular block will report more frequent current utilization of alternatives to the conventional inferior alveolar nerve block than clinicians trained in the conventional technique only. At the 95 percent confidence level, we estimated that between 3.7 percent and 16.1 percent (mean=8.5 percent) of clinicians trained in using the Gow-Gates technique use this injection technique primarily, and between 35.4 percent and 56.3 percent (mean=47.5 percent) of those trained in the Gow-Gates method never use this technique. At the same confidence level, between 0.0 percent and 3.8 percent (mean=0.0 percent) of clinicians trained in using the Akinosi technique use this injection clinical technique primarily, and between 62.2 percent and 81.1 percent (mean=72.3 percent) of those trained in the Akinosi method never use this technique. No control group that was completely untrained in the Gow-Gates or Akinosi techniques was available for comparison. However, we presume that zero percent of clinicians who have not been trained in a given technique will use the technique in clinical practice. The confidence interval for the Gow-Gates method excludes this value, while the confidence interval for the Akinosi technique includes zero percent. We conclude that, in the study population, formal clinical training in the Gow-Gates and

  6. Quasi-trapezoidal pulses to selectively block the activation of intrinsic laryngeal muscles during vagal nerve stimulation

    NASA Astrophysics Data System (ADS)

    Tosato, M.; Yoshida, K.; Toft, E.; Struijk, J. J.

    2007-09-01

    The stimulation of the vagus nerve has been used as an anti-epileptic treatment for over a decade, and its use for depression and chronic heart failure is currently under investigation. Co-activation of the intrinsic laryngeal muscles may limit the clinical use of vagal stimulation, especially in the case of prolonged activation. To prevent this, the use of a selective stimulation paradigm has been tested in seven acute pig experiments. Quasi-trapezoidal pulses successfully blocked the population of the largest and fastest vagal myelinated fibers being responsible for the co-activation. The first response in the vagus compound action potential was reduced by 75 ± 22% (mean ± SD) and the co-activated muscle action potential by 67 ± 25%. The vagal bradycardic effects remained unchanged during the selective block, confirming the leading role of thin nerve fibers for the vagal control of the heart. Quasi-trapezoidal pulses may be an alternative to rectangular pulses in clinical vagal stimulation when the co-activation of laryngeal muscles must be avoided.

  7. The Role of 5-HT3 Receptors in Signaling from Taste Buds to Nerves.

    PubMed

    Larson, Eric D; Vandenbeuch, Aurelie; Voigt, Anja; Meyerhof, Wolfgang; Kinnamon, Sue C; Finger, Thomas E

    2015-12-01

    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.

  8. The Role of 5-HT3 Receptors in Signaling from Taste Buds to Nerves.

    PubMed

    Larson, Eric D; Vandenbeuch, Aurelie; Voigt, Anja; Meyerhof, Wolfgang; Kinnamon, Sue C; Finger, Thomas E

    2015-12-01

    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. PMID:26631478

  9. The effect of preemptive pudendal nerve block on pain after anterior and posterior vaginal repair

    PubMed Central

    Rouholamin, Safoura; Jabalameli, Mitra; Mostafa, Abedi

    2015-01-01

    Introduction: Anterior and posterior vaginal repair (APR) is a common surgery for women with prolapse of pelvic organs which creates post-operative pain because of damage of tissues that we should manage and control this pain. For this purpose, this study was conducted in order to evaluate the effect of preemptive pudendal nerve block on post-operative pain in anterior and posterior vaginal wall repair. Materials and Methods: In a double-blinded clinical trial study, 60 women candidates of APR were randomly divided to two groups. In both of them was injected 0.3 cc/kg bupivacaine 0.25% for the intervention group or normal saline for the control group in pudendal nerve tract with the guide of nerve stimulator. A visual analog scale was used to measure pain during the first 48 h after the surgery. Data were analyzed by repeated measures analysis of variance (ANOVA). Results: Compared with the intervention group, the control group experienced greater pain during rest and walking. There were significant differences between the two groups from the first post-operative hour (P = 0.003) until 48 h after the operation (P = 0.021). Furthermore, the mean ± SD values of pain in the sitting position was not significantly different between control and intervention groups at the same time (P = 0.340). Conclusion: Preemptive pudendal nerve block can reduce post-operative pain score in anterior and posterior vaginal wall repair and this method was suggested in anterior and posterior vaginal wall repair. PMID:26380238

  10. A comparative study of direct mandibular nerve block and the Akinosi technique.

    PubMed

    Martínez González, José Ma; Benito Peña, Begoña; Fernández Cáliz, Fernando; San Hipólito Marín, Lara; Peñarrocha Diago, Miguel

    2003-01-01

    A study is made of 56 patients subjected to lower molar extraction, comparing the efficacy of the Akinosi technique as an alternative to direct or conventional mandibular nerve block in two groups of 28 subjects each. The parameters evaluated were pain in response to puncture, percentage positive aspiration, latency, pain during the intervention and complications. Patient pain in response to puncture was comparatively less intense and frequent with the Akinosi technique. The latency to anesthesia was briefer with conventional mandibular block than with the Akinosi technique (2.9 versus 3.8 minutes). Pain during the intervention and the duration of the anesthetic effect were similar for both techniques. The patients anesthetized with the Akinosi technique required more buccal nerve reinforcement infiltrations to complete the procedure. The anesthetic failure rates were 10.7% and 17.8% for the conventional and Akinosi technique, respectively. It is concluded that while the Akinosi technique can be used to extract lower molars, direct mandibular block offers superior anesthetic performance.

  11. Long-term effect of ropivacaine nanoparticles for sciatic nerve block on postoperative pain in rats

    PubMed Central

    Wang, Zi; Huang, Haizhen; Yang, Shaozhong; Huang, Shanshan; Guo, Jingxuan; Tang, Qi; Qi, Feng

    2016-01-01

    Purpose The analgesic effect of ropivacaine (Rop) for nerve block lasts only ~3–6 hours for single use. The aim of this study was to develop long-acting regional anesthetic Rop nanoparticles and investigate the effects of sciatic nerve block on postoperative pain in rats. Materials and methods Rop nanoparticles were developed using polyethylene glycol-co-polylactic acid (PELA). One hundred and twenty adult male Wistar rats were randomly divided into four groups (n=30, each): Con (control group; 0.9% saline, 200 µL), PELA (PELA group; 10 mg), Rop (Rop group; 0.5%, 200 µL), and Rop-PELA (Rop-PELA group; 10%, 10 mg). Another 12 rats were used for the detection of Rop concentration in plasma. The mechanical withdrawal threshold and thermal withdrawal latency were measured at 2 hours, 4 hours, 8 hours, 1 day, 2 days, 3 days, 5 days, and 7 days after incision. The expression of c-FOS was determined by immunohistochemistry at 2 hours, 8 hours, 48 hours, and 7 days. Nerve and organ toxicities were also evaluated at 7 days. Results The duration of Rop absorption in the plasma of the Rop-PELA group was longer (>8 hours) than that of the Rop group (4 hours). Mechanical withdrawal threshold and thermal withdrawal latency in the Rop-PELA group were higher than that in other groups (4 hours–3 days). c-FOS expression in the Rop-PELA group was lower than that in the control group at 2 hours, 8 hours, and 48 hours and lower than that in the Rop group at 8 hours and 48 hours after paw incision. Slight foreign body reactions were observed surrounding the sciatic nerve at 7 days. No obvious pathophysiological change was found in the major organs after Rop-PELA administration at 7 days. Conclusion Rop-PELA provides an effective analgesia for nerve block over 3 days after single administration, and the analgesic mechanism might be mediated by the regulation of spinal c-FOS expression. However, its potential long-term tissue toxicity needs to be further investigated. PMID:27274236

  12. Peripheral nerve blocks in patients with Ehlers-Danlos syndrome, hypermobility type: a report of 2 cases.

    PubMed

    Patzkowski, Michael S

    2016-03-01

    Ehlers-Danlos syndrome is an inherited disorder of collagen production that results in multiorgan dysfunction. Patients with hypermobility type display skin hyperextensibility and joint laxity, which can result in chronic joint instability, dislocation, peripheral neuropathy, and severe musculoskeletal pain. A bleeding diathesis can be found in all subtypes of varying severity despite a normal coagulation profile. There have also been reports of resistance to local anesthetics in these patients. Several sources advise against the use of regional anesthesia in these patients citing the 2 previous features. There have been reports of successful neuraxial anesthesia, but few concerning peripheral nerve blocks, none of which describe nerves of the lower extremity. This report describes 2 cases of successful peripheral regional anesthesia in the lower extremity. In case 1, a 16-year-old adolescent girl with hypermobility type presented for osteochondral grafting of tibiotalar joint lesions. She underwent a popliteal sciatic (with continuous catheter) and femoral nerve block under ultrasound guidance. She proceeded to surgery and tolerated the procedure under regional block and intravenous sedation. She did not require any analgesics for the following 15 hours. In case 2, an 18-year-old woman with hypermobility type presented for medial patellofemoral ligament reconstruction for chronic patella instability. She underwent a saphenous nerve block above the knee with analgesia in the distribution of the saphenous nerve lasting for approximately 18 hours. There were no complications in either case. Prohibitions against peripheral nerve blocks in patients with Ehlers-Danlos syndrome, hypermobility type, appear unwarranted.

  13. Peripheral nerve blocks in patients with Ehlers-Danlos syndrome, hypermobility type: a report of 2 cases.

    PubMed

    Patzkowski, Michael S

    2016-03-01

    Ehlers-Danlos syndrome is an inherited disorder of collagen production that results in multiorgan dysfunction. Patients with hypermobility type display skin hyperextensibility and joint laxity, which can result in chronic joint instability, dislocation, peripheral neuropathy, and severe musculoskeletal pain. A bleeding diathesis can be found in all subtypes of varying severity despite a normal coagulation profile. There have also been reports of resistance to local anesthetics in these patients. Several sources advise against the use of regional anesthesia in these patients citing the 2 previous features. There have been reports of successful neuraxial anesthesia, but few concerning peripheral nerve blocks, none of which describe nerves of the lower extremity. This report describes 2 cases of successful peripheral regional anesthesia in the lower extremity. In case 1, a 16-year-old adolescent girl with hypermobility type presented for osteochondral grafting of tibiotalar joint lesions. She underwent a popliteal sciatic (with continuous catheter) and femoral nerve block under ultrasound guidance. She proceeded to surgery and tolerated the procedure under regional block and intravenous sedation. She did not require any analgesics for the following 15 hours. In case 2, an 18-year-old woman with hypermobility type presented for medial patellofemoral ligament reconstruction for chronic patella instability. She underwent a saphenous nerve block above the knee with analgesia in the distribution of the saphenous nerve lasting for approximately 18 hours. There were no complications in either case. Prohibitions against peripheral nerve blocks in patients with Ehlers-Danlos syndrome, hypermobility type, appear unwarranted. PMID:26897449

  14. Preventive effect of ilioinguinal nerve block on postoperative pain after cesarean section

    PubMed Central

    Naghshineh, Elham; Shiari, Samira; Jabalameli, Mitra

    2015-01-01

    Background: Cesarean section is a major operation that can be the predictor of postoperative pain and discomfort and, therefore, providing the effective postoperative analgesia is an important factor to facilitate sooner movement of the patient, better care of infants. The aim of this study was to determine the preventive effect of ilioinguinal nerve block on pain after cesarean section. Materials and Methods: In a randomized clinical trial study, 80 female candidates for cesarean section under general anesthesia were selected and divided into two groups. In the first group, ilioinguinal nerve was blocked and in the control group, ilioinguinal nerve block was not done. Finally, postoperative pain was compared between the two groups. Results: The mean pain intensity at 6 and 24 h after operation had no significant difference between two groups but in the rest of the times, it was different between two groups. Furthermore, in sitting position, except for 6 h, the pain intensity at the rest of the time had a significant difference between two groups. The pain intensity in 12 h after operation had a significant difference while in 24 h after operation; there was no difference between two groups. Doing repeated measures, ANOVA also indicated that the process of changes in the pain intensity in three positions of rest, sitting and walking had no significant difference up to 24 h after operation (P < 0.001). Conclusion: Control of pain after cesarean as one of the most common factors for abdominal surgery will lead to decrease the staying of the patient in hospital, reduce morbidity and lower use of narcotics and analgesics after surgery. PMID:26623404

  15. Incidence of hemidiaphragmatic paresis after peripheral nerve stimulator versus ultrasound guided interscalene brachial plexus block

    PubMed Central

    Ghodki, Poonam Sachin; Singh, Noopur Dasmit

    2016-01-01

    Background and Aims: We compared interscalene brachial plexus block (ISBPB) using peripheral nerve stimulation (PNS) and ultrasound (US) techniques. The primary outcomes were the incidence of hemidiaphragmatic paresis (HDP) and the duration of the block. Secondary outcomes were the block success rate, time to conduct the block, onset of sensory block, and dermatomal spread, postoperative pain by Numeric Rating Scale (NRS), duration of postoperative analgesia and incidence of complications. Material and Methods: We conducted a prospective, randomized, and observer-blinded study in 60 patients undergoing shoulder arthroscopy under block plus general anesthesia. ISBPB was performed with 10 ml of 0.5% bupivacaine using either PNS (Group PNS, n = 30) or US (Group US, n = 30). Hemidiaphragmatic function, the primary outcome, was assessed by ultrasonographic evaluation of diaphragmatic movement and pulmonary function tests using a bedside spirometer (forced vital capacity, forced expiratory volume in 1 s and peak expiratory flow rate). General anesthesia was administered to all the patients for surgery. P < 0.05 test was considered to be statistically significant. Results: Twelve patients in Group PNS had HDP and none in Group US (P < 0.0001). PFTs were also significantly reduced in Group PNS (P < 0.0001). The time to conduct the block and sensory onset time both were less in Group US (P < 0.05). The groups did not differ in block success rate, duration of analgesia, and NRS. Other complications like incidence of Horner's syndrome and vascular puncture were comparable in both the groups. Conclusions: PNS guided ISBPB with 10 ml of 0.5% bupivacaine is associated with a higher incidence of HDP as compared to US guided ISBPB. There is no significant difference in quality or duration of analgesia in the two groups. PMID:27275045

  16. Neurotoxicity of perineural vs intraneural-extrafascicular injection of liposomal bupivacaine in the porcine model of sciatic nerve block.

    PubMed

    Damjanovska, M; Cvetko, E; Hadzic, A; Seliskar, A; Plavec, T; Mis, K; Vuckovic Hasanbegovic, I; Stopar Pintaric, T

    2015-12-01

    Liposomal bupivacaine is a prolonged-release local anaesthetic, the neurotoxicity of which has not yet been determined. We used quantitative histomorphometric and immunohistochemical analyses to evaluate the neurotoxic effect of liposomal bupivacaine after perineural and intraneural (extrafascicular) injection of the sciatic nerve in pigs. In this double-blind prospective randomised trial, 4 ml liposomal bupivacaine 1.3% was injected either perineurally (n = 5) or intraneurally extrafascicularly (n = 5). Intraneural-extrafascicular injection of saline (n = 5) was used as a control. After emergence from anaesthesia, neurological examinations were conducted over two weeks. After harvesting the sciatic nerves, no changes in nerve fibre density or myelin width indicative of nerve injury were observed in any of the groups. Intraneural injections resulted in longer sensory blockade than perineural (p < 0.003) without persistent motor or sensory deficit. Sciatic nerve block with liposomal bupivacaine in pigs did not result in histological evidence of nerve injury.

  17. Perioperative continuous peripheral nerve blocks with disposable infusion pumps in children: a prospective descriptive study.

    PubMed

    Dadure, Christophe; Pirat, Philippe; Raux, Olivier; Troncin, Rachel; Rochette, Alain; Ricard, Christine; Capdevila, Xavier

    2003-09-01

    Continuous peripheral nerve blocks (CPNB) after pediatric major orthopedic surgery are not widely used. We conducted a prospective descriptive study to evaluate the effectiveness of disposable elastomeric pumps for CPNB in children. After inducing general anesthesia, 25 consecutive children scheduled for major orthopedic surgery received a 0.5-mL/kg bolus of a mixture of 1% lidocaine with epinephrine and 0.25% bupivacaine in axillary, femoral, or popliteal catheters. After surgery, disposable pumps with 0.2% ropivacaine were connected. Pump flows were adjusted to the patient's weight. Postoperative pain was evaluated using a visual analog scale or Children and Infants Postoperative Pain Scale scores at H1, H6, H12, H24, and H48, as well as amounts of rescue analgesia, adverse events, and motor and sensory block. An ambulation score for the children was also evaluated. Eleven popliteal, nine femoral, and five axillary continuous blocks were performed. All the blocks were effective for surgery. The mean total dose consumption of 0.2% ropivacaine was 10.1 mg/kg. Disposable pump flow varied from -9.61% to +8.6% compared with the theoretical one. Postoperative analgesia was excellent. The median of pain score was zero at each period studied. Sensory and motor block were noted at H1 and decreased from the sixth hour. No adverse events were noted. We concluded that the use of elastomeric disposable pumps for CPNB in children was an effective technique. PMID:12933385

  18. Anesthetic efficacy of an infiltration in mandibular anterior teeth following an inferior alveolar nerve block.

    PubMed Central

    Clark, Kenneth; Reader, Al; Beck, Mike; Meyers, William J.

    2002-01-01

    The purpose of this prospective, randomized, blinded study was to measure the degree of pulpal anesthesia obtained with an inferior alveolar nerve (IAN) block followed by an infiltration in mandibular anterior teeth. Through use of a repeated-measures design, 40 patients randomly received 3 injection combinations at 3 separate appointments: an IAN block followed by a mock lingual infiltration and a mock labial infiltration, an IAN block followed by a mock lingual infiltration and a labial infiltration, and an IAN block followed by a mock labial infiltration and a lingual infiltration. Each IAN block used 3.6 mL of 2% lidocaine with 1:100,000 epinephrine, and each infiltration used 1.8 mL of 2% lidocaine with 1:100,000 epinephrine administered over the lateral incisor apex. Mandibular anterior teeth were blindly pulp tested at 2-minute cycles for 60 minutes following the IAN-infiltration injections. No response from the patient to the maximum output (80 reading) of the pulp tester was used as the criterion for pulpal anesthesia. Anesthesia was considered successful when 2 consecutive 80 readings were obtained within 15 minutes and the 80 reading was sustained for 60 minutes. Anesthesia was considered a failure if 2 consecutive 80 readings were not obtained during the 60 minutes. The results of this study showed that 100% of the patients had lip numbness with all IAN blocks. For the lateral incisor, the success rate of the IAN block alone was 40% and the failure rate was 30%. For the IAN block plus labial infiltration, the success rate was 62% and the failure rate was 12% for the lateral incisor. There was a significant difference (P < .05) between the IAN block alone and the IAN block plus labial infiltration. In conclusion, a labial infiltration, over the lateral incisor apex, of 1.8 mL of 2% lidocaine with 1:100,000 epinephrine following an IAN block significantly improved pulpal anesthesia for the lateral incisor compared with the IAN block alone. PMID:15384292

  19. Femoral and sciatic nerve block for knee arthroscopy in a patient with acute intermittent porphyria.

    PubMed

    Bosch, L; Villar, T; Latorre, M Y; Pacreu, S

    2016-01-01

    Acute intermittent porphyria is an autosomal dominant disorder that results from a partial deficiency of porphobilinogen deaminase and that causes very severe symptoms. Attacks may be triggered by a series of drugs and by other factors that the anesthesiologist should be aware of in order to reduce morbidity and mortality. Our objective is to review anesthetic considerations in acute intermittent porphyria. We present the case of a patient diagnosed with acute intermittent porphyria who was scheduled for knee arthroscopy. The anesthetic technique used was a femoral and sciatic nerve block under sedation with an infusion of remifentanil. The surgery proceeded without incident and the patient was discharged home after 24h. We consider the use of a peripheral plexus block of the lower limb to have been the safest anesthetic technique for this patient. PMID:27220836

  20. Optimal Effect of Phenol Block in the Sciatic Nerve of Rats: Standardization of Minimized Dosage and Duration of Application.

    PubMed

    Lin, Chuan-Chao; Chang, Chein-Wei; Tsai, Su-Ju

    2015-08-31

    The phenol nerve block has been widely used in clinical practice for spasticity reduction, but the correlation between the dosage of phenol and its effectiveness has seldom been discussed. The objective was to determine the optimal duration of phenol in contact with the nervous tissue and to investigate the dose-response relationship of 5% aqueous phenol solution by percutaneous nerve block in rats. Group I (n = 8) received sciatic nerve block by bathing the nerves in phenol solution, and group II (n = 40) by injecting phenol percutaneously. Group IIa to IId received different volumes (0.80, 0.16, 0.08 and 0.04 ml) and group IIe received normal saline. Compound muscle action potential (CMAP) was measured pre-injection and at 90 and 270 sec after injection and after surgical exposure of the nerves. The duration of CMAP reduced by 10%, 25%, 50%, 75% and 100% after phenol injection was also recorded. The mean latency for the evoked response to subside in direct phenol application (group I) and percutaneous nerve block (group IIa) were 73.5 ± 5.9 and 62.4 ± 7.6 sec, respectively. There was no statistical difference for the time periods in the blocking effect elicited by phenol solution between these two methods. Ninety sec was set as the optimal duration for phenol to produce complete conduction blockage. Higher volume of phenol produced more significant blocking effect at 90 and 270 sec after injection. Percutaneous injection with 0.16 ml of phenol solution had the same blocking effect as 0.8 ml. The continuous injection model for percutaneous phenol block indeed used significantly more phenol than actually needed. Clinically, the progressive injection model can be used to minimize injection volume.

  1. Optimal Effect of Phenol Block in the Sciatic Nerve of Rats: Standardization of Minimized Dosage and Duration of Application.

    PubMed

    Lin, Chuan-Chao; Chang, Chein-Wei; Tsai, Su-Ju

    2015-08-31

    The phenol nerve block has been widely used in clinical practice for spasticity reduction, but the correlation between the dosage of phenol and its effectiveness has seldom been discussed. The objective was to determine the optimal duration of phenol in contact with the nervous tissue and to investigate the dose-response relationship of 5% aqueous phenol solution by percutaneous nerve block in rats. Group I (n = 8) received sciatic nerve block by bathing the nerves in phenol solution, and group II (n = 40) by injecting phenol percutaneously. Group IIa to IId received different volumes (0.80, 0.16, 0.08 and 0.04 ml) and group IIe received normal saline. Compound muscle action potential (CMAP) was measured pre-injection and at 90 and 270 sec after injection and after surgical exposure of the nerves. The duration of CMAP reduced by 10%, 25%, 50%, 75% and 100% after phenol injection was also recorded. The mean latency for the evoked response to subside in direct phenol application (group I) and percutaneous nerve block (group IIa) were 73.5 ± 5.9 and 62.4 ± 7.6 sec, respectively. There was no statistical difference for the time periods in the blocking effect elicited by phenol solution between these two methods. Ninety sec was set as the optimal duration for phenol to produce complete conduction blockage. Higher volume of phenol produced more significant blocking effect at 90 and 270 sec after injection. Percutaneous injection with 0.16 ml of phenol solution had the same blocking effect as 0.8 ml. The continuous injection model for percutaneous phenol block indeed used significantly more phenol than actually needed. Clinically, the progressive injection model can be used to minimize injection volume. PMID:26211647

  2. Continuous Ilioinguinal-iliohypogastric Nerve Block for Groin Pain in a Breast-feeding Patient after Cesarean Delivery

    PubMed Central

    Kim, Eun Soo; Baik, Ji Seok; Ji, Young Tae

    2016-01-01

    Ilioinguinal and iliohypogastric (II/IH) nerve injury is one of the most common nerve injuries following pelvic surgery, especially with the Pfannenstiel incision. We present a case of intractable groin pain, successfully treated with a continuous II/IH nerve block. A 33-year-old woman, following emergency cesarean section due to cephalopelvic disproportion, presented numbness in left inguinal area and severe pain on the labia on the second postoperative day. The pain was burning, lancinating, and exacerbated by standing or movement. However, she didn't want to take additional medicine because of breast-feeding. A diagnostic II/IH nerve block produced a substantial decrease in pain. She underwent a continuous II/IH nerve block with a complete resolution of pain within 3 days. A continuous II/IH nerve block might be a goodoption for II/IH neuropathy with intractable groin pain in breast-feeding mothers without adverse drug reactions in their infants. PMID:27413486

  3. Essential oil of Croton zehntneri and its main constituent anethole block excitability of rat peripheral nerve.

    PubMed

    da Silva-Alves, Kerly Shamyra; Ferreira-da-Silva, Francisco Walber; Coelho-de-Souza, Andrelina Noronha; Albuquerque, Aline Alice Cavalcante; do Vale, Otoni Cardoso; Leal-Cardoso, José Henrique

    2015-03-01

    Croton zehntneri is an aromatic plant native to Northeast Brazil and employed by local people to treat various diseases. The leaves of this plant have a rich content of essential oil. The essential oil of C. zehntneri samples, with anethole as the major constituent and anethole itself, have been reported to have several pharmacological activities such as antispasmodic, cardiovascular, and gastroprotective effects and inducing the blockade of neuromuscular transmission and antinociception. Since several works have demonstrated that essential oils and their constituents block cell excitability and in view of the multiple effects of C. zehntneri essential oil and anethole on biological tissues, we undertook this investigation aiming to characterize and compare the effects of this essential oil and its major constituent on nerve excitability. Sciatic nerves of Wistar rats were used. They were mounted in a moist chamber, and evoked compound action potentials were recorded. Nerves were exposed in vitro to the essential oil of C. zehntneri and anethole (0.1-1 mg/mL) up to 180 min, and alterations in excitability (rheobase and chronaxie) and conductibility (peak-to-peak amplitude and conduction velocity) parameters of the compound action potentials were evaluated. The essential oil of C. zehntneri and anethole blocked, in a concentration-dependent manner with similar pharmacological potencies (IC50: 0.32 ± 0.07 and 0.22 ± 0.11 mg/mL, respectively), rat sciatic nerve compound action potentials. Strength-duration curves for both agents were shifted upward and to the right compared to the control curve, and the rheobase and chronaxie were increased following essential oil and anethole exposure. The time courses of the essential oil of C. zehntneri and anethole effects on peak-to-peak amplitude of compound action potentials followed an exponential decay and reached a steady state. The essential oil of C. zehntneri and anethole caused a similar reduction in

  4. Cortisol and pain-related behavior in disbudded goat kids with and without cornual nerve block.

    PubMed

    Alvarez, L; De Luna, J B; Gamboa, D; Reyes, M; Sánchez, A; Terrazas, A; Rojas, S; Galindo, F

    2015-01-01

    Plasma cortisol and behavior were measured in disbudded goat kids with and without the use of cornual nerve block. A total of 45 kids were used in 5 experimental groups (n=9, males and females). Group LidoD was infiltrated with 1 mL of 2% lidocaine locally at the cornual branches of lacrimal and infratrochlear nerves, 15 min before thermal disbudding. Group Lido was similarly infiltrated and was not disbudded. In group Sim, the disbudding procedure was simulated. A control group (CD) was disbudded without lidocaine infiltration, and group SD was infiltrated with saline before disbudding. The cornual nerve block did not prevent the short-term increase in cortisol levels during and after disbudding. LidoD, CD and SD groups showed higher cortisol concentrations than Lido and Sim (p<0.05) during the first 20 min after the procedure. Frequency of vocalizations during the procedure was significantly different between groups and was higher in SD (29.6 ± 3.1; mean±SE) and CD (28.4 ± 3.1) than in Sim (16.6 ± 3.1; p<0.05). Infiltrating lidocaine did not decrease this response to disbudding (21.1 ± 3.1; p>0.05). Struggles tended to be higher in SD (16.5 ± 2.5), CD (17.8 ± 2.5) and LidoD (15.6 ± 2.5) than Sim (10.6 ± 2.5; p=0.1). The total behavioral response was different between groups (CD, 59.6 ± 6.8; LidoD, 52 ± 6.8; SD, 62.6 ± 6.8; Sim, 36.8 ± 6.8; p=0.05), and disbudded animals showed the strongest reactions (disbudded, 58.1 ± 3.9 vs non-disbudded, 36.8 ± 6.8; p=0.01). It was concluded that cornual nerve block (lacrimal and infratrochlear) using 2% lidocaine did not prevent pain during thermal disbudding of goat kids.

  5. Essential oil of Croton zehntneri and its main constituent anethole block excitability of rat peripheral nerve.

    PubMed

    da Silva-Alves, Kerly Shamyra; Ferreira-da-Silva, Francisco Walber; Coelho-de-Souza, Andrelina Noronha; Albuquerque, Aline Alice Cavalcante; do Vale, Otoni Cardoso; Leal-Cardoso, José Henrique

    2015-03-01

    Croton zehntneri is an aromatic plant native to Northeast Brazil and employed by local people to treat various diseases. The leaves of this plant have a rich content of essential oil. The essential oil of C. zehntneri samples, with anethole as the major constituent and anethole itself, have been reported to have several pharmacological activities such as antispasmodic, cardiovascular, and gastroprotective effects and inducing the blockade of neuromuscular transmission and antinociception. Since several works have demonstrated that essential oils and their constituents block cell excitability and in view of the multiple effects of C. zehntneri essential oil and anethole on biological tissues, we undertook this investigation aiming to characterize and compare the effects of this essential oil and its major constituent on nerve excitability. Sciatic nerves of Wistar rats were used. They were mounted in a moist chamber, and evoked compound action potentials were recorded. Nerves were exposed in vitro to the essential oil of C. zehntneri and anethole (0.1-1 mg/mL) up to 180 min, and alterations in excitability (rheobase and chronaxie) and conductibility (peak-to-peak amplitude and conduction velocity) parameters of the compound action potentials were evaluated. The essential oil of C. zehntneri and anethole blocked, in a concentration-dependent manner with similar pharmacological potencies (IC50: 0.32 ± 0.07 and 0.22 ± 0.11 mg/mL, respectively), rat sciatic nerve compound action potentials. Strength-duration curves for both agents were shifted upward and to the right compared to the control curve, and the rheobase and chronaxie were increased following essential oil and anethole exposure. The time courses of the essential oil of C. zehntneri and anethole effects on peak-to-peak amplitude of compound action potentials followed an exponential decay and reached a steady state. The essential oil of C. zehntneri and anethole caused a similar reduction in

  6. A comparison of strength for two continuous peripheral nerve block catheter dressings

    PubMed Central

    Borg, Lindsay; Howard, Steven K.; Kim, T. Edward; Steffel, Lauren; Shum, Cynthia

    2016-01-01

    Background Despite the benefits of continuous peripheral nerve blocks, catheter dislodgment remains a major problem, especially in the ambulatory setting. However, catheter dressing techniques to prevent such dislodgment have not been studied rigorously. We designed this simulation study to test the strength of two commercially available catheter dressings. Methods Using a cadaver model, we randomly assigned 20 trials to one of two dressing techniques applied to the lateral thigh: 1) clear adhesive dressing alone, or 2) clear adhesive dressing with an anchoring device. Using a digital luggage scale attached to a loop secured by the dressing, the same investigator applied steadily increasing force with a downward trajectory towards the floor until the dressing was removed or otherwise disrupted. Results The weight, measured (median [10th–90th percentile]) at the time of dressing disruption or removal, was 1.5 kg (1.3–1.8 kg) with no anchoring device versus 4.9 kg (3.7–6.5 kg) when the dressing included an anchoring device (P < 0.001). Conclusions Based on this simulation study, using an anchoring device may help prevent perineural catheter dislodgement and therefore premature disruption of continuous nerve block analgesia.

  7. [Continuing peripheral nerve blocks - benefit for orthopedic patients with diabetes mellitus?].

    PubMed

    Doležal, David; Saleh, Abdo Islam

    2015-06-01

    There is increasing incidence of diabetes mellitus in population of developed countries. And there is also, together with this fact, an increasing frequency of surgical not only orthopedic procedures for diabetic complications or for other reasons. However, thanks to modern sophisticated perioperative approaches, diabetes itself is no longer main risk factor for worsening of perioperative morbidity and mortality. The organ complications of diabetes still remain the crucial for patients outcome. The individual approach to each patient is important when we are plann-ing anesthesiological perioperative strategy. Assessment of long term diabetes compensation before elective surgical procedures, assessment and optimization of organ functions with searching for possible secondary complications of diabetes is also crucial. Generally, it is necessary to maintain compensation of diabetes through the whole perioperative period, avoid episodes of hypotension and tissue hypoperfusion and all anesthesiological interventions have to be targeted to rapid recovery (chronic medication, oral feeding and early rehabilitation). Technics of regional anesthesia and peripheral nerve blocks particularly, may be very useful for the objective especially for ortho-pedic patients.Key words: anesthesia - diabetes mellitus - perioperative period - peripheral nerve blocks.

  8. Cervical foraminal selective nerve root block: a 'two-needle technique' with results.

    PubMed

    Kumar, Naresh; Gowda, Veda

    2008-04-01

    Several techniques have been described for selective nerve root blocks. We describe a novel 'two-needle technique', performed through the postero-lateral route with the patient in lateral position under C-arm guidance. The aim of the current study is to highlight the effectiveness and safety of cervical selective nerve root block for radiculopathy using this technique. We present results of a retrospective 2-year follow-up study of 33 injections carried out on 33 patients with radiculopathy due to cervical disc disease and or foraminal stenosis using this procedure. Patients with myelopathy, gross motor weakness and any other pathology were excluded. The outcome was measured comparing 'Visual Analogue Score' (VAS) and 'Neck Disability Index' (NDI) before the procedure with those at 6 weeks and 12 months after the procedure. Thirty patients were included in the final analysis. Average pre-operative VAS score was 7.4 (range 5-10), which improved to 2.2 (range 0-7) at 6 weeks and 2.0 (range 0-4) at 1 year and the mean NDI score prior to intervention was 66.9 (range 44-84), which improved to 31.7 (range 18-66) at 6 weeks and 31.1 (range 16-48) at 1 year. The improvements were statistically significant. Patients with involvement of C6 or C7 nerve roots responded slightly better at 6 weeks with regards to VAS improvement. Mean duration of radiation exposure during the procedure was 27.8 s (range 10-90 s). Only minor complications were noted-transient dizziness in two and transient nystagmus in one patient. Our 'two-needle technique' is a new, safe and effective non-surgical treatment for cervical radiculopathy.

  9. Reversible nerve conduction block in patients with polyneuropathy after ultrasound thermotherapy at therapeutic dosage.

    PubMed

    Hong, C Z

    1991-02-01

    This study investigated the effect of ultrasound on nerve conduction in patients with polyneuropathy. Eight able-bodied controls (Group C) and 16 patients with clinical and physiologic evidence of polyneuropathy were tested. Eight patients (Group NP) had no aching pain symptoms; eight patients (Group P) had severe aching pain, burning sensation, unpleasant tingling, and/or hyperesthesia in the lower extremities. For two minutes, therapeutic ultrasound in doses of 0.5, 1.0, and 1.5W/cm2 were applied over the anterior surface of the leg along the pathway of the deep peroneal nerve. Peroneal nerve conduction studies were performed before, during, and after ultrasound treatment. The compound muscle action potential (CMAP) was recorded from the extensor digitorum brevis muscle. Nerve conduction studies on all eight patients in Group P revealed a significant decrease (41.4% and 44% reduced for doses of 1.0W/cm2 and 1.5W/cm2, respectively; p less than .05) in amplitude of CMAP (from baseline to the first negative peak), and an increase (6.4% and 6.7% increased for doses of 1.0W/cm2 and 1.5W/cm2, respectively; p less than .05) in proximal latency one minute after ultrasound application with a dose of 1.0 or 1.5W/cm2, but not with a dose of 0.5W/cm2 (p greater than 0.1). Changes returned to pretreatment values within five minutes of cessation of ultrasound therapy. In Groups C and NP, there were no significant changes in amplitudes of CMAP or proximal latency before, during, or after ultrasound therapy at a dose of 0.5, 1.0, or 1.5W/cm2. It was concluded that ultrasonic therapy with therapeutic dosage may cause a reversible conduction block on patients with painful polyneuropathy.

  10. Comparison of Periodontal Ligament Injection and Inferior Alveolar Nerve Block in Mandibular Primary Molars Pulpotomy: A Randomized Control Trial

    PubMed Central

    Haghgoo, Roza; Taleghani, Ferial

    2015-01-01

    Background: Inferior alveolar nerve block is a common technique for anesthesia of the primary mandibular molars. A number of disadvantages have been shown to be associated with this technique. Periodontal ligament (PDL) injection could be considered as an alternative to inferior alveolar nerve block. The aim of this study was to evaluate the effectiveness of PDL injection in the anesthesia of primary molar pulpotomy with mandibular block. Methods: This study was performed using a sequential double-blind randomized trial design. 80 children aged 3-7 years old who required pulpotomy in symmetrical mandibular primary molars were selected. The teeth of these children were anesthetized with periodontal injection on one side of the mandible and block on the other. Pulpotomy was performed on each patient during the same appointment. Signs of discomfort, including hand and body tension and eye movement, the verbal complaint and crying (SEM scale), were evaluated by a dental assistant who was blinded to the treatment allocation of the patients. Finally, the data were analyzed using the exact Fisher test and Pearson Chi-squared exact test. Results: Success rate was 88/75 and 91/25 in the PDL injection and nerve block groups, respectively. There was no statistically significant difference between the two techniques (P = 0.250). Conclusion: Results showed that PDL injection can be used as an alternative to nerve block in pulpotomy of the mandibular primary molars. PMID:26028895

  11. Ultrasound-guided Continuous Axillary Brachial Plexus Block Using a Nerve Stimulating Catheter: EpiStim® Catheter

    PubMed Central

    Lee, Mi Kyoung; Kim, Jung Eun; Kim, Se Hee; Yeo, Gwi Eun

    2015-01-01

    Brachial plexus block (BPB) under ultrasound guidance has come to be widely used. However, nerve injury has been reported following ultrasound-guided BPB. We hypothesized that BPB under ultrasound guidance in conjunction with real-time electrical nerve stimulation would help us prevent nerve injury and do more successful procedure. Here, we report the successful induction and maintenance of ultrasound-guided BPB and the achievement of good peri- and postoperative pain control using a conductive catheter, the EpiStim®. PMID:26495085

  12. Blocking Nerve Growth Factor Signaling Reduces the Neural Invasion Potential of Pancreatic Cancer Cells

    PubMed Central

    Bapat, Aditi A.; Munoz, Ruben M.; Von Hoff, Daniel D.

    2016-01-01

    Perineural invasion (PNI) is thought to be one of the factors responsible for the high rate of tumor recurrence after surgery and the pain generation associated with pancreatic cancer. Signaling via the nerve growth factor (NGF) pathway between pancreatic cancer cells and the surrounding nerves has been implicated in PNI, and increased levels of these proteins have been correlated to poor prognosis. In this study, we examine the molecular mechanism of the NGF signaling pathway in PNI in pancreatic cancer. We show that knocking down NGF or its receptors, TRKA and p75NTR, or treatment with GW441756, a TRKA kinase inhibitor, reduces the proliferation and migration of pancreatic cancer cells in vitro. Furthermore, pancreatic cancer cells migrate towards dorsal root ganglia (DRG) in a co-culture assay, indicating a paracrine NGF signaling between the DRGs and pancreatic cancer cells. Knocking down the expression of NGF pathway proteins or inhibiting the activity of TRKA by GW441756 reduced the migratory ability of Mia PaCa2 towards the DRGs. Finally, blocking NGF signaling by NGF neutralizing antibodies or GW441756 inhibited the neurite formation in PC-12 cells in response to conditioned media from pancreatic cancer cells, indicating a reciprocal signaling pathway between the pancreatic cancer cells and nerves. Our results indicate that NGF signaling pathway provides a potential target for developing molecularly targeted therapies to decrease PNI and reduce pain generation. Since there are several TRKA antagonists currently in early clinical trials they could now be tested in the clinical situation of pancreatic cancer induced pain. PMID:27792755

  13. Thermal hyperalgesia after sciatic nerve block in rat is transient and clinically insignificant.

    PubMed

    Janda, Allison; Lydic, Ralph; Welch, Kathleen B; Brummett, Chad M

    2013-01-01

    Ropivacaine has been associated with transient heat hyperalgesia in sciatic nerve blocks in rat. The goal of the present study was to evaluate the hypothesized presence of transient heat hyperalgesia after perineural injection of ropivacaine with a secondary subanalysis of 2 published studies. Paw withdrawal latency was used to assess the duration of sensory blockade and presence of heat hyperalgesia at 210, 240, 270, and 300 minutes and 24 hours after injection. The analysis revealed hyperalgesia at a single time point (240 minutes after injection; mean difference, -0.60 seconds; P = 0.012) that resolved within 30 minutes, and there was no other significant hyperalgesia at other time points. Although statistically significant, the single time point measurement represented only an 11% change from baseline and was no longer present 30 minutes later. These data support the need for a reevaluation of the interpretation that pain can be worsened by perineural ropivacaine injection.

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

    PubMed

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

    2013-08-01

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

  15. Paravertebral Nerve Block for Donor Site Pain in Stage I Microtia Reconstruction: A Pilot Study.

    PubMed

    Shaffer, Amber D; Jabbour, Noel; Visoiu, Mihaela; Yang, Charles I; Yellon, Robert F

    2016-05-01

    Acute Interventional Perioperative Pain Service consultants have routinely placed paravertebral nerve block (PVB) catheters for the continuous release of ropivacaine following stage I microtia reconstruction with costal cartilage graft at our institution since 2010. A retrospective chart review from July 2006 was performed to compare the length of hospital stay, median pain score (0-10 scale), and opioid use of patients receiving PVB with those of historical controls. Statistical analysis included t, Mann-Whitney U, and Fisher's exact tests. A total of 15 stage I microtia surgeries were included, 10 with PVB and 5 without. Patients with and without PVB had high peak pain scores (8.4 vs 7.8), remained in the hospital for 3.5 and 3.8 days, and consumed 0.69 and 0.36 mg/kg morphine equivalents, respectively. These findings highlight the feasibility of PVB, but larger studies are needed to optimize pain relief in this population. PMID:26908556

  16. Relationships between block-of-twitch and train-of-four fade in the mouse phrenic nerve-diaphragm preparation.

    PubMed

    Storella, R J; Slomowitz, S A; Rosenberg, H

    1991-04-01

    The relationships between the block-of-twitch and train-of-four fade in the presence of nondepolarizing neuromuscular blocking drugs (d-tubocurarine, vecuronium and pancuronium) were examined in vitro by measuring the contractile tension from mouse phrenic nerve-diaphragm preparations. The slope of the block/fade relationship differed between onset of and recovery from neuromuscular block following single doses of d-tubocurarine, vecuronium or pancuronium. Decreasing the dose of d-tubocurarine or using a divided dose technique to accelerate onset (i.e., priming) increased the amount of fade for a given amount of block. In addition, the block/fade relationships for cumulative dosing and sequential dilution were the same when measurements were made at steady-state for several doses. It is concluded that the block/fade relationship in the mouse phrenic nerve-diaphragm preparation is variable, and is related to the time course of the neuromuscular block. In addition, the block/fade relationships for d-tubocurarine, vecuronium and pancuronium did not differ when determined at steady-state.

  17. Essential Oil of Ocimum basilicum L. and (-)-Linalool Blocks the Excitability of Rat Sciatic Nerve.

    PubMed

    Medeiros Venancio, Antonio; Ferreira-da-Silva, Francisco Walber; da Silva-Alves, Kerly Shamyra; de Carvalho Pimentel, Hugo; Macêdo Lima, Matheus; Fraga de Santana, Michele; Barreto Alves, Péricles; Batista da Silva, Givanildo; Leal-Cardoso, José Henrique; Marchioro, Murilo

    2016-01-01

    The racemate linalool and its levogyrus enantiomer [(-)-LIN] are present in many essential oils and possess several pharmacological activities, such as antinociceptive and anti-inflammatory. In this work, the effects of essential oil obtained from the cultivation of the Ocimum basilicum L. (EOOb) derived from Germplasm Bank rich in (-)-LIN content in the excitability of peripheral nervous system were studied. We used rat sciatic nerve to investigate the EOOb and (-)-LIN effects on neuron excitability and the extracellular recording technique was used to register the compound action potential (CAP). EOOb and (-)-LIN blocked the CAP in a concentration-dependent way and these effects were reversible after washout. EOOb blocked positive amplitude of 1st and 2nd CAP components with IC50 of 0.38 ± 0.2 and 0.17 ± 0.0 mg/mL, respectively. For (-)-LIN, these values were 0.23 ± 0.0 and 0.13 ± 0.0 mg/mL. Both components reduced the conduction velocity of CAP and the 2nd component seems to be more affected than the 1st component. In conclusion EOOb and (-)-LIN inhibited the excitability of peripheral nervous system in a similar way and potency, revealing that the effects of EOOb on excitability are due to the presence of (-)-LIN in the essential oil.

  18. Essential Oil of Ocimum basilicum L. and (-)-Linalool Blocks the Excitability of Rat Sciatic Nerve.

    PubMed

    Medeiros Venancio, Antonio; Ferreira-da-Silva, Francisco Walber; da Silva-Alves, Kerly Shamyra; de Carvalho Pimentel, Hugo; Macêdo Lima, Matheus; Fraga de Santana, Michele; Barreto Alves, Péricles; Batista da Silva, Givanildo; Leal-Cardoso, José Henrique; Marchioro, Murilo

    2016-01-01

    The racemate linalool and its levogyrus enantiomer [(-)-LIN] are present in many essential oils and possess several pharmacological activities, such as antinociceptive and anti-inflammatory. In this work, the effects of essential oil obtained from the cultivation of the Ocimum basilicum L. (EOOb) derived from Germplasm Bank rich in (-)-LIN content in the excitability of peripheral nervous system were studied. We used rat sciatic nerve to investigate the EOOb and (-)-LIN effects on neuron excitability and the extracellular recording technique was used to register the compound action potential (CAP). EOOb and (-)-LIN blocked the CAP in a concentration-dependent way and these effects were reversible after washout. EOOb blocked positive amplitude of 1st and 2nd CAP components with IC50 of 0.38 ± 0.2 and 0.17 ± 0.0 mg/mL, respectively. For (-)-LIN, these values were 0.23 ± 0.0 and 0.13 ± 0.0 mg/mL. Both components reduced the conduction velocity of CAP and the 2nd component seems to be more affected than the 1st component. In conclusion EOOb and (-)-LIN inhibited the excitability of peripheral nervous system in a similar way and potency, revealing that the effects of EOOb on excitability are due to the presence of (-)-LIN in the essential oil. PMID:27446227

  19. Pain relief in active patients with cancer: the early use of nerve blocks improves the quality of life.

    PubMed Central

    Lipton, S.

    1989-01-01

    Analgesic drugs are the first line of pain relief in cancer, but they should not be the only treatment offered. If nerve blocks and other destructive procedures are to be used they should be used early with conviction and persistence. They might not be being used because there are not enough doctors who can use them properly. PMID:2465046

  20. Preemptive Oral Clonidine Provides Better Sedation Than Intravenous Midazolam in Brachial Plexus Nerve Blocks

    PubMed Central

    Mosaffa, Faramarz; Mohajerani, Seyed Amir; Aminnejad, Reza; Solhpour, Ali; Dabir, Shideh; Mohseni, Gholam Reza

    2016-01-01

    Background Preemptive analgesia is the blocking of pain perception afferent pathways before noxious painful stimuli. Clonidine is an alpha agonist drug that is partially selective for α-2 adrenoreceptors. Clonidine is used as anti-anxiety medication and an, analgesic, and it prolongs the duration of the block in the brachial plexus block. Objectives To compare the effect of preemptive clonidine with midazolam on intraoperative sedation, duration of block, and postoperative pain scores. Patients and Methods In a randomized clinical trial, 80 patients with orthopedic fractures of an upper extremity who underwent supraclavicular nerve block were randomly assigned to receive 0.2 mg oral clonidine or 2 mg oral midazolam. Intraoperative sedation was measured at one hour after the start of urgery and again in the PACU (Post-Anesthesia Care Unit) using the Ramsay scale. The duration of sensory blockade was measured. Postoperative pain scores were measured using the VAS (Visual Analogue Scale) after entrance to recovery up to 2 hours. Results The percentages of patients in the calm and sedated scale were significantly higher in clonidine group (35 and 42.5%, respectively), compared to the midazolam group (17.5 and 17.5%, respectively) (P = 0.042, 0.029; respectively). Those administered fentanyl in the clonidine group 105 ± 30.8 was significantly lower than that for the midazolam group 165 ± 34.5 (P = 0.0018). The percentages of patients in the calm scale were significantly higher in the clonidine group (52.5), compared to the midazolam group (17.5) (P = 0.001) in the post-operative period. VAS scores were significantly lower at one (P = 0.01) and two hours (P = 0.001) after operation in the clonidine group, compared to the midazolam group. Conclusions Preemptive clonidine has many marvelous advantages over midazolam, including better sedation inside the operating room and then in the post-operative care unit, lower fentanyl doses are required during surgery, more stable

  1. Ultrasound-Guided Forearm Nerve Blocks: A Novel Application for Pain Control in Adult Patients with Digit Injuries

    PubMed Central

    Patricia Javedani, Parisa; Amini, Albert

    2016-01-01

    Phalanx fractures and interphalangeal joint dislocations commonly present to the emergency department. Although these orthopedic injuries are not complex, the four-point digital block used for anesthesia during the reduction can be painful. Additionally, cases requiring prolonged manipulation or consultation for adequate reduction may require repeat blockade. This case series reports four patients presenting after mechanical injuries resulting in phalanx fracture or interphalangeal joint dislocations. These patients received an ultrasound-guided peripheral nerve block of the forearm with successful subsequent reduction. To our knowledge, use of ultrasound-guided peripheral nerve blocks of the forearm for anesthesia in reduction of upper extremity digit injuries in adult patients in the emergency department setting has not been described before. PMID:27555971

  2. Effect of prostate volume on the peripheral nerve block anesthesia in the prostate biopsy

    PubMed Central

    Luan, Yang; Huang, Tian-bao; Gu, Xiao; Zhou, Guang-Chen; Lu, Sheng-Ming; Tao, Hua-Zhi; Liu, Bi-De; Ding, Xue-Fei

    2016-01-01

    Abstract Objective: The objective of this study was to evaluate the anesthetic efficacy of periprostatic nerve block (PNB) in transrectal ultrasound (TRUS)-guided biopsy on different prostate volume. Methods: A total of 568 patients received prostate biopsy in our hospital from May 2013 to September 2015 and were retrospectively studied. All patients were divided into local anesthesia group (LAG) and nerve block group (NBG). Then each group was subdivided into 4 subgroups (20–40, 40–60, 60–100, and >100 mL groups) according to different prostate volume range. Visual analogue scale (VAS) and visual numeric scale (VNS) were used to assess the patient's pain and quantify their satisfaction. The scores and complications were compared between the groups. Results: The age and serum prostate-specific antigen (PSA) level before biopsy had no significant differences at intergroup or intragroup level. The VAS scores were significantly lower in the NBG than those in the LAG in terms of prostate volume (1 (1–2) versus 2 (1–3), 2 (1–3) versus 2 (2–4), 2 (2–3) versus 3 (2–5), 4 (3–5) versus 5 (4–7), all P < 0.05). Conversely, the VNS scores were higher in the NBG (4 (3–4) versus 3.5 (3–4), 3 (3–4) versus 3 (3–3), 3 (2–4) versus 3 (2–3), 2 (2–2) versus 1 (1–2), all P < 0.05). Patients with smaller prostate volume undergoing PNB or local anesthesia experienced significantly lower pain and higher satisfaction scores than those with large prostate. Whether in PNB or local anesthesia group, patients with large prostate volume had more chance to have hematuria, hemospermia, urinary retention than smaller one except infection (P < 0.05). Those complications had no significant differences between LAG and NBG (P > 0.05). Conclusion: Compared with local anesthesia, ultrasound-guided PNB has superior analgesic effect and equal safety, but for patients with a large prostate volume, the analgesic effect is inefficient. PMID:27428215

  3. Efficacy and complications associated with a modified inferior alveolar nerve block technique. A randomized, triple-blind clinical trial

    PubMed Central

    Montserrat-Bosch, Marta; Nogueira-Magalhães, Pedro; Arnabat-Dominguez, Josep; Valmaseda-Castellón, Eduard; Gay-Escoda, Cosme

    2014-01-01

    Objectives: To compare the efficacy and complication rates of two different techniques for inferior alveolar nerve blocks (IANB). Study Design: A randomized, triple-blind clinical trial comprising 109 patients who required lower third molar removal was performed. In the control group, all patients received an IANB using the conventional Halsted technique, whereas in the experimental group, a modified technique using a more inferior injection point was performed. Results: A total of 100 patients were randomized. The modified technique group showed a significantly higher onset time in the lower lip and chin area, and was frequently associated to a lingual electric discharge sensation. Three failures were recorded, 2 of them in the experimental group. No relevant local or systemic complications were registered. Conclusions: Both IANB techniques used in this trial are suitable for lower third molar removal. However, performing an inferior alveolar nerve block in a more inferior position (modified technique) extends the onset time, does not seem to reduce the risk of intravascular injections and might increase the risk of lingual nerve injuries. Key words:Dental anesthesia, inferior alveolar nerve block, lidocaine, third molar, intravascular injection. PMID:24608204

  4. Alternative to the inferior alveolar nerve block anesthesia when placing mandibular dental implants posterior to the mental foramen.

    PubMed

    Heller, A A; Shankland, W E

    2001-01-01

    Local anesthesia block of the inferior alveolar nerve is routinely taught throughout dental education. This commonly used technique eliminates all somatosensory perception of the mandible, mandibular teeth, floor of the mouth, ipsilateral tongue, and all but the lateral (buccal) gingivae. Generally, the dentist or surgeon desires these structures to be anesthetized. However, in the placement of mandibular implants, it may be useful for the patient to be able to sense when the inferior alveolar nerve is in danger of being damaged, possibly producing permanent paresthesia. In this article, the technique of mandibular infiltration prior to mandibular implant placement in the mandible is discussed. PMID:12500871

  5. Influences of continuous femoral nerve block on knee function and quality of life in patients following total knee arthroplasty

    PubMed Central

    Wang, Fen; Zhou, Yingjie; Sun, Jiajun; Yang, Chunxi

    2015-01-01

    Objective: Continuous femoral nerve block (CFNB), guided by ultrasound combined nerve stimulations, offers advantages for both sides and provides effective postoperative analgesia after total knee arthroplasty (TKA). The objective of this study was to evaluate the medium-term impact of continuous femoral nerve block on knee function and quality of life in patients following TKA. Methods: This was a follow-up study. Total 168 adult patients scheduled for elective TKA were randomly allocated to receive postoperative continuous femoral nerve block guided by ultrasound combined nerve stimulator (group CFNB, n = 82) or patient-controlled epidural analgesia (group PCEA, n = 86). Quality of life, knee function, patient satisfaction, pain medication and associated adverse effects were compared at 1, 3, 6, and 12 months postoperatively. Quality of life was assessed using the Medical Outcomes Study Short Form-36 Health Survey (MOS SF-36), and clinical results were assessed using the Hospital for Special Surgery (HSS) Knee Scoring System. Patient satisfaction scores were divided into four categories. Results: A total of 162 patients completed the 12-month follow-up. The CFNB group patients had significantly improved SF-36 scores and physical function at 1 month postoperatively (P < 0.05); the remaining seven dimensions were similar between the two groups. No differences were observed at 3, 6 or 12 months. HSS scores for the four observational time points were comparable. The CFNB group patients reported less pain; improved knee function, maximum flexion and strength; less celecoxib consumption and fewer side effects at 1 month than the PCEA group patients. The satisfaction score at 12 months decreased significantly, compared with that at 1 month in both groups (3.6 to 2.95 and 3.4 to 2.45, respectively). No difference in satisfaction score was observed between the two groups. Conclusions: Continuous femoral nerve block not only could provide effective postoperative analgesia

  6. Bilateral Infraorbital Nerve Block Versus Intravenous Pentazocine: A Comparative Study on Post-operative Pain Relief Following Cleft Lip Surgery

    PubMed Central

    Grewal, Gurpreeti; Grewal, Anju

    2015-01-01

    Background and Objectives Infra orbital nerve block is utilized for postoperative pain control in children undergoing cleft lip repair. This study was conducted to compare the effectiveness, advantages and disadvantages of infra orbital nerve block and opioids for postoperative pain relief following cheiloplasty. Materials and Methods Sixty paediatric patients aged 3 months – 13 years undergoing cheiloplasty were selected by simple random sampling and were divided into two groups. All the children received standardized premedication with midazolam, were operated upon under general anaesthesia and the block was performed at the end of surgery before reversal. Group B patients were administered bilateral infra orbital nerve block with 0.25% Bupivacaine (upto 2 mg/kg). Group O patients received Pentazocine 0.5 mg / kg IV. Postoperatively, the heart rate and respiratory rates were recorded every 15 minutes for the first 60 minutes, half hourly till 4 hours and then at 12 and 24 hours. Behavioural assessment for pain / discomfort was done at intervals of ½, 1, 2, 3, 4, 12 and 24 hours. Need for supplementary analgesics and duration between the administration of block/opioid and the first dose of supplementary analgesics were noted. Side effects such as nausea and vomiting, pruritus, respiratory depression and bradycardia during each of these periods were noted. Results Both the groups were comparable for age, sex, weight and operative time with no statistical difference. The mean duration of analgesia for infra orbital nerve block was 357.5 minutes i.e. 5 hours 58 minutes and that for opioid was 231 minutes i.e. 3 hours 51 minutes which was significantly lower than the hours of analgesia provided by the block. Further, at the 4th hour, 76.6% of the patients in Group O required supplementary analgesics, in contrast to only 16.6% in Group B. The incidence of nausea and vomiting and pruritus was also higher in Group O. Conclusion The results indicate that bilateral

  7. Ultrasound-guided continuous suprascapular nerve block for adhesive capsulitis: one case and a short topical review.

    PubMed

    Børglum, J; Bartholdy, A; Hautopp, H; Krogsgaard, M R; Jensen, K

    2011-02-01

    We present a case with an ultrasound-guided (USG) placement of a perineural catheter beneath the transverse scapular ligament in the scapular notch to provide a continuous block of the suprascapular nerve (SSN). The patient suffered from a severe and very painful adhesive capsulitis of the left shoulder secondary to an operation in the same shoulder conducted 20 weeks previously for impingement syndrome and a superior labral anterior-posterior tear. Following a new operation with capsular release, the placement of a continuous nerve block catheter subsequently allowed for nearly pain-free low impact passive and guided active mobilization by the performing physiotherapist for three consecutive weeks. This case and a short topical review on the use of SSN block in painful shoulder conditions highlight the possibility of a USG continuous nerve block of the SSN as sufficient pain management in the immediate post-operative period following capsular release of the shoulder. Findings in other painful shoulder conditions and suggestions for future studies are discussed in the text. PMID:21226866

  8. Failure rate of inferior alveolar nerve block among dental students and interns

    PubMed Central

    AlHindi, Maryam; Rashed, Bayan; AlOtaibi, Noura

    2016-01-01

    Objectives: To report the failure rate of inferior alveolar nerve block (IANB) among dental students and interns, causes of failure, investigate awareness of different IANB techniques, and to report IANB-associated complications. Methods: A 3-page questionnaire containing 13 questions was distributed to a random sample of 350 third to fifth years students and interns at the College of Dentistry, King Saud University, Riyadh, Saudi Arabia on January 2011. It included demographic questions (age, gender, and academic level) and questions on IANB failure frequency and reasons, actions taken to overcome the failure, and awareness of different anesthetic techniques, supplementary techniques, and complications. Results: Of the 250 distributed questionnaires, 238 were returned (68% response rate). Most (85.7%) of surveyed sample had experienced IANB failure once or twice. The participants attributed the failures most commonly (66.45%) to anatomical variations. The most common alternative technique used was intraligamentary injection (57.1%), although 42.8% of the sample never attempted any alternatives. Large portion of the samples stated that they either lacked both knowledge of and training for other techniques (44.9%), or that they had knowledge of them but not enough training to perform them (45.8%). Conclusion: To decrease IANB failure rates for dental students and interns, knowledge of landmarks, anatomical variation and their training in alternatives to IANB, such as the Gow-Gates and Akinosi techniques, both theoretically and clinically in the dental curriculum should be enhanced. PMID:26739980

  9. Comparative efficacy of ropivacaine and levobupivacaine in combined femoral and lateral femoral cutaneous nerve block with adjuvant magnesium for post-operative analgesia

    PubMed Central

    Khairnar, Prakash; Agarwal, Munisha; Verma, Uttam Chandra; Kumar, Rakesh

    2016-01-01

    Background and Aims: Patients with burns may require multiple surgeries, but poor general condition and underlying protein energy malnutrition make them unsuitable candidates for general or spinal anaesthesia. This study evaluated the role of magnesium sulphate as an adjuvant with levobupivacaine and ropivacaine used in combined femoral and lateral femoral cutaneous nerve (LFCN) blocks in burn patients with relative sparing of thigh portion. Methods: This prospective, randomised, double-blind study included 54 adult patients of 18–65 years age, undergoing split-thickness skin graft harvest from the thigh, allotted to three equal groups of 18 each. Group L patients received femoral nerve (FN) block with 15 mL of 0.5% levobupivacaine and 8 mL for LFCN block; Group LM patients received 14 mL of 0.5% levobupivacaine along with 1.0 mL of 15% magnesium sulphate for FN block, 7.5 mL of 0.5% levobupivacaine with 0.5 mL of 15% of magnesium sulphate to LFCN block and Group R patients received 15 mL of 0.5% ropivacaine for FN block and 8 mL of 0.5% ropivacaine for LFCN block. Time to block onset and complete surgical block, duration of analgesia, total analgesic dose and the overall analgesia satisfaction score were measured in the first 24 h post-operatively. Quantitative data were analysed with ANOVA and qualitative data subjected to Chi-square tests. Intergroup comparison was performed with independent t-test. Results: The duration of post-operative analgesia did not differ with the addition of magnesium (P = 0.610). Time to onset of the block was significantly decreased with the addition of magnesium (P = 0.0341), but time to complete surgical block onset was similar across the groups. Conclusion: Both ropivacaine and levobupivacaine have good perioperative analgesic efficacy. Magnesium as an analgesia adjuvant with levobupivacaine does not prolong the duration of post-operative analgesia. PMID:27601742

  10. Self-consistent analyses for potential conduction block in nerves by an ultrashort high-intensity electric pulse

    NASA Astrophysics Data System (ADS)

    Joshi, R. P.; Mishra, A.; Hu, Q.; Schoenbach, K. H.; Pakhomov, A.

    2007-06-01

    Simulation studies are presented that probe the possibility of using high-field (>100kV/cm) , short-duration (˜50ns) electrical pulses for nonthermal and reversible cessation of biological electrical signaling pathways. This would have obvious applications in neurophysiology, clinical research, neuromuscular stimulation therapies, and even nonlethal bioweapons development. The concept is based on the creation of a sufficiently high density of pores on the nerve membrane by an electric pulse. This modulates membrane conductance and presents an effective “electrical short” to an incident voltage wave traveling across a nerve. Net blocking of action potential propagation can then result. A continuum approach based on the Smoluchowski equation is used to treat electroporation. This is self-consistently coupled with a distributed circuit representation of the nerve dynamics. Our results indicate that poration at a single neural segment would be sufficient to produce an observable, yet reversible, effect.

  11. Clinical evaluation of inferior alveolar nerve block by injection into the pterygomandibular space anterior to the mandibular foramen.

    PubMed Central

    Takasugi, Y.; Furuya, H.; Moriya, K.; Okamoto, Y.

    2000-01-01

    The conventional inferior alveolar nerve block (conventional technique) has potential risks of neural and vascular injuries. We studied a method of inferior alveolar nerve block by injecting a local anesthetic solution into the pterygomandibular space anterior to the mandibular foramen (anterior technique) with the purpose of avoiding such complications. The insertion angle of the anterior technique and the estimation of anesthesia in the anterior technique were examined. The predicted insertion angle measured on computed tomographic images was 60.1 +/- 7.1 degrees from the median, with the syringe end lying on the contralateral mandibular first molar, and the insertion depth was approximately 10 mm. We applied the anterior technique to 100 patients for mandibular molar extraction and assessed the anesthetic effects. A success rate of 74% was obtained. This is similar to that reported for the conventional technique but without the accompanying risks for inferior alveolar neural and vascular complications. Images Figure 2 PMID:11432177

  12. Lower cervical nerve root block using CT fluoroscopy in patients with large body habitus: another benefit of the swimmer's position.

    PubMed

    Bartynski, W S; Whitt, D S; Sheetz, M A; Jennings, R B; Rothfus, W E

    2007-04-01

    We describe a method of performing lower cervical nerve root block (CNRB) with CT fluoroscopy in patients with large body habitus using the swimmer's position. This approach reduces image noise with acceptable visualization of vital structures and improved foraminal/root access. Anticipated use of the swimmer's position coupled with minimally modified radiation exposure parameters can limit radiation dose to operator/patient and reduce procedure time to match that of CNRB using CT fluoroscopy in typical patients.

  13. Comparative outcomes of peripheral nerve blocks versus general anesthesia for hip fractures in geriatric Chinese patients

    PubMed Central

    Liu, Jun Le; Wang, Xiao Lin; Gong, Mao Wei; Mai, Hai Xing; Pei, Shu Jun; Yuan, Wei Xiu; Zhang, Hong

    2014-01-01

    Background Geriatric patients undergoing hemiarthroplasty for hip fractures have unacceptably high rates of postoperative complications and mortality. Whether anesthesia type can affect the outcomes has still been inconclusive. Objectives We compared general anesthesia (GA) and peripheral nerve blocks (PNBs) on postoperative complications and mortality in elderly patients with femoral neck fractures (FNF) undergoing hemiarthroplasty. Materials and methods This retrospective study involved data collection from an electronic database. Two hundred and seventeen patients underwent hemiarthroplasty for FNF between January 2008 and December 2012 at the Chinese People’s Liberation Army General Hospital. Data on mortality within in-hospital, 30-day, and 1-year, complications, comorbidities, blood loss and transfusion, operative time, postoperative hospital length of stay, intensive care unit admission, and hospital charge were collected and analyzed. Univariate and multivariate Cox regression analyses of all variables were used for 30-day and 1-year mortality. Results Seventy-two patients receiving GA and 145 receiving PNBs were eventually submitted and analyzed. Mortality was 6.9%, 14.7%, and 23.5% at in-hospital, 30-day, and 1-year, respectively postoperatively, while mortality and cardiovascular complications did not differ between the two anesthetic techniques. Preoperative comorbidities and intraoperative parameters were not statistically different except that patients receiving GA were more likely to have dementia (χ2=10.45, P=0.001). The most common complications were acute cardiovascular events, electrolyte disturbances, and delirium. Postoperative acute respiratory events and hypoxemia both were also common, but no differences were found between groups (χ2=0.68, P=0.410; χ2=3.42, P=0.065, respectively). Key factors negatively influencing mortality included: age, male gender, American Society of Anesthesiologists status, dementia, perioperative cardiovascular

  14. Preoperatıve Ultrasound-Guıded Suprascapular Nerve Block for Postthoracotomy Shoulder Paın☆

    PubMed Central

    Özyuvaci, Emine; Akyol, Onat; Şitilci, Tolga; Dübüs¸, Türkan; Topac¸ogˇlu, Hakan; Leblebici, Hülya; Ac¸ikgöz, Alican

    2013-01-01

    Background Acute postthoracotomy pain is a well-known potential problem, with pulmonary complications, ineffective respiratory rehabilitation, and delayed mobilization in the initial postoperative period, and it is followed by chronic pain. The type of thoracotomy, intercostal nerve damage, muscle retraction, costal fractures, pleural irritation, and incision scar are the most responsible mechanisms. Objective Our aim was to assess whether preoperative ultrasound suprascapular nerve block with thoracic epidural analgesia was effective for postthoracotomy shoulder pain relief. Methods Thirty-six American Society of Anesthesiologist classification physical status I–III patients (2011–2012), with a diagnosis of lung cancer and scheduled for elective open-lung surgery, were prospectively included in the study. Eighteen of the patients received an ultrasound-guided suprascapular nerve block with 10-mL 0.5% levobupivacaine, using a 22-gauge spinal needle, 1 hour before operation (group S); 18 other patients had thoracic epidural analgesia only, and no nerve block was performed. Standard general anesthesia was administered. Degree of shoulder pain was assessed by a blinded observer when discharging patients from the recovery room, and thereafter at 1, 3, 6, 12, 24, 36, 48, and 72 hours on infusion at rest and 12, 24, 36, 48, and 72 hours on coughing. The same blinded observer also recorded the total amount of epidural levobupivacaine and fentanyl used by the 2 groups. Results In the suprascapular block group, the total amount of levobupivacaine (P = 0.0001) and fentanyl (P = 0.005) used postoperatively was statistically lower than in the epidural group. Visual analogue scale measurements in the suprascapular group were statistically significantly lower at 0, 1, 3, 6, 12, 24, 36, and 48 hours than those in the epidural group, both at rest and coughing. Conclusion Postthoracotomy shoulder pain reduces patient function and postsurgical rehabilitation potential after

  15. Efficacy of arthroscopically placed pain catheter adjacent to the suprascapular nerve (continuous arthroscopically assisted suprascapular nerve block) following arthroscopic rotator-cuff repair

    PubMed Central

    Yamakado, Kotaro

    2014-01-01

    Background Rotator-cuff surgery is well recognized to be a painful procedure. Objectives The purpose of this study was to examine the effectiveness of an arthroscopically placed perineural catheter at the scapular notch to provide a continuous block of the suprascapular nerve (continuous arthroscopically assisted suprascapular nerve block [ca-SSNB]) following arthroscopic rotator-cuff repair (ARCR). Materials and methods This level II, prospective, randomized, controlled trial without postoperative blinding included 40 patients, who had a 48-hour pain pump, with 0.2% ropivacaine infusion and a continuous rate of 3 mL/hour, placed via an arthroscopically placed catheter following ARCR with arthroscopic release of the superior transverse ligament: 21 patients had a ca-SSNB, and 19 patients had a continuous subacromial bursal block (SAB). The visual analog scale (at 6 hours and on the first, second, and third postoperative days) and the total number of additional pain-reduction attempts during the 3 postoperative days were calculated. Results The respective visual analog scale scores (mm) obtained from the ca-SSNB and SAB groups were 62.4 and 67.6 (P=0.73) before surgery, 9.1 and 19.4 (P=0.12) at 6 hours after surgery, 24.4 and 44.6 (P=0.019) on the first postoperative day, 19.4 and 40.4 (P=0.0060) on the second postoperative day, and 18.5 and 27.8 (P=0.21) on the third postoperative day. Total additional pain-reduction attempts recorded for the ca-SSNB and SAB groups during the 3 postoperative days were 0.3 times and 1.2 times (P=0.0020), respectively. Conclusion ca-SSNB was highly effective in controlling postoperative pain after ARCR. PMID:24982592

  16. The role of exosomes in peripheral nerve regeneration

    PubMed Central

    Ching, Rosanna C.; Kingham, Paul J.

    2015-01-01

    Peripheral nerve injuries remain problematic to treat, with poor functional recovery commonly observed. Injuries resulting in a nerve gap create specific difficulties for axonal regeneration. Approaches to address these difficulties include autologous nerve grafts (which are currently the gold standard treatment) and synthetic conduits, with the latter option being able to be impregnated with Schwann cells or stem cells which provide an appropriate micro-environment for neuronal regeneration to occur. Transplanting stem cells, however, infers additional risk of malignant transformation as well as manufacturing difficulties and ethical concerns, and the use of autologous nerve grafts and Schwann cells requires the sacrifice of a functioning nerve. A new approach utilizing exosomes, secreted extracellular vesicles, could avoid these complications. In this review, we summarize the current literature on exosomes, and suggest how they could help to improve axonal regeneration following peripheral nerve injury. PMID:26109947

  17. Continuous Suprascapular Nerve Block With a Perineural Catheter for Reverse Shoulder Arthroplasty Rescue Analgesia in a Patient With Severe Chronic Obstructive Pulmonary Disease.

    PubMed

    Careskey, Matthew; Naidu, Ramana

    2016-07-15

    Reverse open shoulder arthroplasty requires a comprehensive analgesic plan involving regional anesthesia. The commonly performed interscalene brachial plexus blockade confers a high likelihood of diaphragmatic paralysis via phrenic nerve palsy, making this option riskier in patients with limited pulmonary reserve. Continuous blockade of the suprascapular nerve, a more distal branch of the C5 and C6 nerve roots, may be a viable alternative. We report a successful case of the use of a suprascapular nerve block with continuous programmed intermittent bolus perineural analgesia in a patient with severe chronic obstructive pulmonary disease who underwent reverse open shoulder arthroplasty. PMID:27258178

  18. Role of renal sensory nerves in physiological and pathophysiological conditions

    PubMed Central

    2014-01-01

    Whether activation of afferent renal nerves contributes to the regulation of arterial pressure and sodium balance has been long overlooked. In normotensive rats, activating renal mechanosensory nerves decrease efferent renal sympathetic nerve activity (ERSNA) and increase urinary sodium excretion, an inhibitory renorenal reflex. There is an interaction between efferent and afferent renal nerves, whereby increases in ERSNA increase afferent renal nerve activity (ARNA), leading to decreases in ERSNA by activation of the renorenal reflexes to maintain low ERSNA to minimize sodium retention. High-sodium diet enhances the responsiveness of the renal sensory nerves, while low dietary sodium reduces the responsiveness of the renal sensory nerves, thus producing physiologically appropriate responses to maintain sodium balance. Increased renal ANG II reduces the responsiveness of the renal sensory nerves in physiological and pathophysiological conditions, including hypertension, congestive heart failure, and ischemia-induced acute renal failure. Impairment of inhibitory renorenal reflexes in these pathological states would contribute to the hypertension and sodium retention. When the inhibitory renorenal reflexes are suppressed, excitatory reflexes may prevail. Renal denervation reduces arterial pressure in experimental hypertension and in treatment-resistant hypertensive patients. The fall in arterial pressure is associated with a fall in muscle sympathetic nerve activity, suggesting that increased ARNA contributes to increased arterial pressure in these patients. Although removal of both renal sympathetic and afferent renal sensory nerves most likely contributes to the arterial pressure reduction initially, additional mechanisms may be involved in long-term arterial pressure reduction since sympathetic and sensory nerves reinnervate renal tissue in a similar time-dependent fashion following renal denervation. PMID:25411364

  19. Effect of adding tetracaine to bupivacaine on duration of analgesia in supraclavicular brachial plexus nerve blocks for ambulatory shoulder surgery

    PubMed Central

    Pearson, Linda T.; Lowry, Benjamin P.; Culp, William C.; Kitchings, Olen E.; Meyer, Tricia A.; McAllister, Russell K.; Roberson, Charles R.

    2015-01-01

    The objective of this study was to determine if the addition of 1% tetracaine to 0.25% bupivacaine prolonged the duration of postoperative analgesia of supraclavicular brachial plexus nerve blockade for patients undergoing ambulatory shoulder surgery. We conducted a prospective, double-blinded, randomized controlled clinical study at an ambulatory surgery center utilizing ultrasound- and nerve stimulation-guided supraclavicular nerve blockade for postoperative analgesia. The control group received 30 mL of 0.25% bupivacaine plus 4 mL preservative-free saline. The study group received 30 mL of 0.25% bupivacaine plus 4 mL of 1% tetracaine. Patients documented their visual analog scale scores and intake of pain medications for 3 days. Primary outcomes included time of first postoperative pain, time of first postoperative pain pill, and time of return of motor and sensory function. Secondary outcomes included pain score and pain medication intake trends and adverse events secondary to the nerve block. A total of 84 patients completed the study, 42 patients in each group. The study group was statistically significantly older than the control group (mean age, 54 vs 48 years; P = 0.04). The mean duration of analgesia was 16.6 ± 8.3 h for the control group and 17.1 ± 7.3 h for the study group (P = 0.69). No outcomes were statistically different. In conclusion, there was no significant difference in duration of postoperative analgesia with the addition of 1% tetracaine to 0.25% bupivacaine in supraclavicular brachial plexus nerve blockade. No differences were identified in postoperative pain medications, pain scores, or complications. PMID:26130874

  20. Anti-neurofilament antibodies in neuropathy with monoclonal gammopathy of undetermined significance produce experimental motor nerve conduction block.

    PubMed

    Stubbs, Evan B; Lawlor, Mike W; Richards, Michael P; Siddiqui, Kiran; Fisher, Morris A; Bhoopalam, Nirmala; Siegel, George J

    2003-02-01

    Elevated levels of serum antibodies to neurofilament proteins have been associated with a variety of neurological diseases, including autoimmune disorders such as neuropathy with monoclonal gammopathy of undetermined significance (MGUS). The pathological significance of anti-neurofilament antibodies in sera of affected patients, however, remains unclear. In this study, we report our findings of polyclonal antibodies in sera from 4 of 16 IgG MGUS neuropathy patients that react strongly on immunoblot with a high molecular weight neurofilament protein (NFH). The effect of anti-NFH polyclonal antibody on peripheral nerve function was tested in vivo by intraneural injection. Sera containing anti-NFH antibody, but not sera from age-matched control subjects, injected into the endoneurium of rat sciatic nerve significantly attenuated proximal-evoked motor nerve compound muscle action potential (CMAP) amplitudes in a complement-dependent manner. In contrast, ankle-evoked CMAP amplitudes were unaffected by intraneural injection of sera containing anti-NFH antibody. Anti-NFH serum-injected nerves showed changes in both axon caliber (shrinkage) and myelin ultrastructure (vesiculation and ovoid formation), suggestive of intramyelinic edema. Preincubation of sera containing anti-NFH antibody with purified NFH protein abolished immunoreactivity to NFH protein and neutralized the serum-mediated toxicity. The data suggest that anti-NFH polyclonal antibodies occurring in sera of some patients with IgG MGUS neuropathy may elicit peripheral nerve conduction block independent of the patients' IgG paraprotein. Anti-neural polyclonal antibodies in sera of IgG MGUS neuropathy patients may have a greater pathological significance than previously anticipated.

  1. Medial and Lateral Pectoral Nerve Block with Liposomal Bupivacaine for the Management of Postsurgical Pain after Submuscular Breast Augmentation

    PubMed Central

    Barlow, Mark; Carpin, Kimberly; Piña, Edward M.; Casso, Daniel

    2014-01-01

    Summary: This report describes an ultrasound-guided medial and lateral pectoralis nerve block using liposome bupivacaine, performed before the surgical incision, in a patient undergoing submuscular breast augmentation. The anatomic basis and technique are described. This procedure may be offered to patients undergoing submuscular insertion of a breast implant or tissue expander. Advancements in ultrasound guidance allow for more precise anatomic placement of local anesthetic agents. The injection technique used for this procedure resulted in complete relaxation of the pectoralis major, facilitating the surgical dissection and markedly diminishing postsurgical pain and muscle spasms. PMID:25587516

  2. Greater occipital nerve blocks in the treatment of refractory chronic migraine: An observational report of nine cases

    PubMed Central

    Koçer, Abdulkadir

    2016-01-01

    AIM To report the effects of greater occipital nerve (GON) blocks on refractory chronic migraine headache. METHODS Nine patients who were receiving the conventionally accepted preventive therapies underwent treatment with repeated GON block to control chronic migraine resistant to other treatments. GON blocking with lidocaine and normal saline mixture was administered by the same physician at hospital once a month (for three times in total). Patients were assessed before the injection and every month thereafter for pain frequency and severity, number of times analgesics were used and any appearant side effects during a 6 mo follow-up. RESULTS Eight of nine patients reported a marked decrease in frequency and severity of migraine attacks in comparison to their baseline symptoms; one reported no significant change (not more than 50%) from baseline and did not accept the second injection. GON block resulted in considerable reduction in pain frequency and severity and need to use analgesics up to three months after the injection in the present cases. The patients did not report any adverse effects. CONCLUSION Hereby we noticed a remarkable success with refractory chronic migraine patients. We believe that this intervention can result in rapid relief of pain with the effects lasting for perhaps several weeks or even months. Further controlled clinical trials are warranted to evaluate the effect of GON block in the treatment of refractory migraine cases. PMID:27803914

  3. Combined continuous "3-in-1" and sciatic nerve blocks provide improved postoperative analgesia with no correlation to catheter tip location after unilateral total knee arthroplasty.

    PubMed

    Rajeev, Subramanyam; Batra, Yatindra Kumar; Panda, Nidhi Bidyut; Kumar, Mukesh; Nagi, Onkar Nath

    2007-12-01

    This study assessed the efficacy and duration of postoperative analgesia after continuous sciatic nerve block with and without continuous "3-in-1" block with bupivacaine after unilateral total knee arthroplasty and determined catheter tip correlation with analgesia. Thirty patients were randomized into 2 groups. Results suggested significantly reduced pain and rescue analgesic requirement in combined sciatic and 3-in-1 (group TS) compared to 3-in-1 group alone (group T). The postoperative pain-free interval and satisfaction score was significantly higher in the combined group (P < .05). The percentage of catheters in the ideal position was 53.3% for 3-in-1 and 93.3% for sciatic nerve. In conclusion, continuous sciatic nerve block when added to continuous 3-in-1 block provides a better quality of analgesia with lesser requirements of rescue analgesics without the need for routine radiographic conformation.

  4. Scaffolds from block polyurethanes based on poly(ɛ-caprolactone) (PCL) and poly(ethylene glycol) (PEG) for peripheral nerve regeneration.

    PubMed

    Niu, Yuqing; Chen, Kevin C; He, Tao; Yu, Wenying; Huang, Shuiwen; Xu, Kaitian

    2014-05-01

    Nerve guide scaffolds from block polyurethanes without any additional growth factors or protein were prepared using a particle leaching method. The scaffolds of block polyurethanes (abbreviated as PUCL-ran-EG) based on poly(ɛ-caprolactone) (PCL-diol) and poly(ethylene glycol) (PEG) possess highly surface-area porous for cell attachment, and can provide biochemical and topographic cues to enhance tissue regeneration. The nerve guide scaffolds have pore size 1-5 μm and porosity 88%. Mechanical tests showed that the polyurethane nerve guide scaffolds have maximum loads of 4.98 ± 0.35 N and maximum stresses of 6.372 ± 0.5 MPa. The histocompatibility efficacy of these nerve guide scaffolds was tested in a rat model for peripheral nerve injury treatment. Four types of guides including PUCL-ran-EG scaffolds, autograft, PCL scaffolds and silicone tubes were compared in the rat model. After 14 weeks, bridging of a 10 mm defect gap by the regenerated nerve was observed in all rats. The nerve regeneration was systematically characterized by sciatic function index (SFI), histological assessment including HE staining, immunohistochemistry, ammonia silver staining, Masson's trichrome staining and TEM observation. Results revealed that polyurethane nerve guide scaffolds exhibit much better regeneration behavior than PCL, silicone tube groups and comparable to autograft. Electrophysiological recovery was also seen in 36%, 76%, and 87% of rats in the PCL, PUCL-ran-EG, and autograft groups respectively, whilst 29.8% was observed in the silicone tube groups. Biodegradation in vitro and in vivo show proper degradation of the PUCL-ran-EG nerve guide scaffolds. This study has demonstrated that without further modification, plain PUCL-ran-EG nerve guide scaffolds can help peripheral nerve regeneration excellently.

  5. Role of neurotrophin in the taste system following gustatory nerve injury.

    PubMed

    Meng, Lingbin; Jiang, Xin; Ji, Rui

    2015-06-01

    Taste system is a perfect system to study degeneration and regeneration after nerve injury because the taste system is highly plastic and the regeneration is robust. Besides, degeneration and regeneration can be easily measured since taste buds arise in discrete locations, and nerves that innervate them can be accurately quantified. Neurotrophins are a family of proteins that regulate neural survival, function, and plasticity after nerve injury. Recent studies have shown that neurotrophins play an important role in the developmental and mature taste system, indicating neurtrophin might also regulate taste system following gustatory nerve injury. This review will summarize how taste system degenerates and regenerates after gustatory nerve cut and conclude potential roles of neurotrophin in regulating the process.

  6. Efficacy of magnesium as an adjuvant to bupivacaine in 3-in-1 nerve block for arthroscopic anterior cruciate ligament repair

    PubMed Central

    Muthiah, Thilaka; Arora, Mahesh K; Trikha, Anjan; Sunder, Rani A; Prasad, Ganga; Singh, Preet M

    2016-01-01

    Background and Aims: Three-in-one and femoral nerve blocks are proven modalities for postoperative analgesia following anterior cruciate ligament (ACL) reconstruction. The aim of this study was to evaluate the efficacy of magnesium (Mg) as an adjuvant to bupivacaine in 3-in-1 block for ACL reconstruction. Methods: Sixty patients undergoing arthroscopic ACL reconstruction were randomly allocated to Group I (3-in-1 block with 30 ml of 0.25% bupivacaine preceded by 1.5 ml of intravenous [IV] saline), Group II (3-in-1 block with 30 ml of 0.25% bupivacaine preceded by 1.5 ml of solution containing 150 mg Mg IV) or Group III (3-in-1 block with 30 ml containing 0.25% bupivacaine and 150 mg of Mg as adjuvant preceded by 1.5 ml of IV saline). Post-operatively, patients received morphine when visual analogue scale (VAS) score was ≥4. Quantitative parameters were compared using one-way ANOVA and Kruskal–Wallis test and qualitative data were analysed using Chi-square test. Results: Demographics, haemodynamic parameters, intra-operative fentanyl requirement, post-operative VAS scores and total morphine requirement were comparable between groups. Time to first analgesic requirement was significantly prolonged in Group III (789 ± 436) min compared to Group I (466 ± 290 min) and Group II (519 ± 274 min), (P = 0.02 and 0.05). Significantly less number of patients in Group III (1/20) received morphine in the first 6 h post-operatively, compared to Group I (8/20) and Group II (6/20) (P = 0.008 and 0.03). No side effects were observed. Conclusion: Mg as an adjuvant to bupivacaine in 3-in-1 block for ACL reconstruction significantly prolongs the time to first analgesic requirement and reduces the number of patients requiring morphine in the immediate post-operative period. PMID:27512165

  7. Ultrasound-Guided Continuous Superficial Radial Nerve Block for Complex Regional Pain Syndrome.

    PubMed

    Henshaw, Daryl S; Kittner, Sarah L; Jaffe, Jonathan D

    2016-06-01

    Although there are many potentially effective therapeutic options for complex regional pain syndrome (CRPS), no definitive treatment exists. Therefore, patients often exhaust both medical and surgical treatment options attempting to find relief for their symptoms. As pain control and restoration of physical movement are primary treatment goals, strategies that include regional anesthesia techniques are commonly employed, but potentially underutilized, treatment modalities. The authors present a patient with refractory CRPS that had significant improvement in both pain control and the ability to tolerate intensive physical therapy following the placement of a superficial radial nerve catheter and an infusion of local anesthetic for 6 days as part of a multimodal analgesic regimen. This treatment approach also assisted in the decision-making process related to future treatment options. Although the use of regional anesthesia and perineural infusions of local anesthetic have previously been described as viable treatment options for CRPS, this case report represents the first known use of a superficial radial nerve catheter for treating CRPS as well as the first description of a technique for placing a superficial radial nerve (SRN) catheter using ultrasound guidance. PMID:27159548

  8. A randomised placebo-controlled trial examining the effect on hand supination after the addition of a suprascapular nerve block to infraclavicular brachial plexus blockade.

    PubMed

    Flohr-Madsen, S; Ytrebø, L M; Valen, K; Wilsgaard, T; Klaastad, Ø

    2016-08-01

    Some surgeons believe that infraclavicular brachial plexus blocks tends to result in supination of the hand/forearm, which may make surgical access to the dorsum of the hand more difficult. We hypothesised that this supination may be reduced by the addition of a suprascapular nerve block. In a double-blind, randomised, placebo-controlled study, our primary outcome measure was the amount of supination (as assessed by wrist angulation) 30 min after infraclavicular brachial plexus block, with (suprascapular group) or without (control group) a supplementary suprascapular block. All blocks were ultrasound-guided. The secondary outcome measure was an assessment by the surgeon of the intra-operative position of the hand. Considering only patients with successful nerve blocks, mean (SD) wrist angulation was lower (33 (27) vs. 61 (44) degrees; p = 0.018) and assessment of the hand position was better (11/11 vs. 6/11 rated as 'good'; p = 0.04) in the suprascapular group. The addition of a suprascapular nerve block to an infraclavicular brachial plexus block can provide a better hand/forearm position for dorsal hand surgery. PMID:27396247

  9. Comparison of Adductor Canal Block and Femoral Nerve Block for Postoperative Pain in Total Knee Arthroplasty: A Systematic Review and Meta-analysis.

    PubMed

    Dong, Cui-Cui; Dong, Shu-Ling; He, Fu-Cheng

    2016-03-01

    A total knee arthroplasty (TKA) has always been associated with moderate-to-severe pain. A systematic review of randomized controlled trials (RCTs) and non-RCTs was performed to evaluate the efficacy and safety of pain control of adductor canal block (ACB) and femoral nerve block (FNB) after TKA.Relevant literatures about the ACB and FNB after TKA for reducing pain were searched from Medline (1996-January, 2015), Embase (1980-January, 2015), PubMed (1980-January, 2015), Web of Science (1980-January, 2015), and The Cochrane Central Register of Controlled Trials. High-quality RCTs and non-RCTs were picked to evaluate the visual analogue scale (VAS) and other outcome. This systematic review and meta-analysis were performed according to the PRISMA statement criteria. The software RevMan 5.30 was used for the meta-analysis.Eight literatures fitted into the inclusion criteria. There were no significant differences in VAS score with rest or mobilization at 4, 24, and 48 h between ACB group and FNB group. There were also no significant differences in the strength of quadriceps and adductor, the length of hospital stay, and complications of vomiting and nausea.Present meta-analysis indicated that ACB shows no superiority than FNB group. Both of them can reduce the pain score after TKA. As referred to which method to adopt, it is determined by the preference of the surgeons and anesthesiologists. PMID:27015172

  10. Femoral nerve block versus adductor canal block for postoperative pain control after anterior cruciate ligament reconstruction: A randomized controlled double blind study

    PubMed Central

    El Ahl, Mohamed Sayed

    2015-01-01

    Background: The objective of this study was to evaluate the reliability of the postoperative pain control using adductor canal block (ACB) compared that using the femoral nerve block (FNB) in patients with anterior cruciate ligament reconstructions (ACLR). Materials and methods: One hundred and twenty-eight patients who had been scheduled to patellar graft ACLR were included in this double blind study, and were randomly allocated into two groups; group ACB and group FNB (64 patients each). All patients received general anesthesia. At the end of the surgery, patients in group FNB received a FNB and those in group ACB received an ACB. The postoperative pain (visual analog scale [VAS]) and muscle weakness were assessed in the postoperative care unit and every 6 h thereafter for 24 h. The total morphine requirements were also recorded. Results: Patients in group ACB had significantly higher VAS (at 18 h and 24 h), higher morphine consumption, but significantly less quadriceps weakness than those in group FNB. Conclusion: In patients with patellar graft ACLR, the ACB can maintain a higher quadriceps power, but with lesser analgesia compared with the FNB. PMID:26240546

  11. Femoral nerve block Intervention in Neck of Femur fracture (FINOF): study protocol for a randomized controlled trial

    PubMed Central

    2014-01-01

    Background Hip fractures are very painful leading to lengthy hospital stays. Conventional methods of treating pain are limited. Non-steroidal anti-inflammatories are relatively contraindicated and opioids have significant side effects.Regional anaesthesia holds promise but results from these techniques are inconsistent. Trials to date have been inconclusive with regard to which blocks to use and for how long. Interpatient variability remains a problem. Methods/Design This is a single centre study conducted at Queen’s Medical Centre, Nottingham; a large regional trauma centre in England. It is a pragmatic, parallel arm, randomized controlled trial. Sample size will be 150 participants (75 in each group). Randomization will be web-based, using computer generated concealed tables (service provided by Nottingham University Clinical Trials Unit). There is no blinding. Intervention will be a femoral nerve block (0.5 mls/kg 0.25% levo-bupivacaine) followed by ropivacaine (0.2% 5 ml/hr−1) infused via a femoral nerve catheter until 48 hours post-surgery. The control group will receive standard care. Participants will be aged over 70 years, cognitively intact (abbreviated mental score of seven or more), able to provide informed consent, and admitted directly through the Emergency Department from their place of residence. Primary outcomes will be cumulative ambulation score (from day 1 to 3 postoperatively) and cumulative dynamic pain scores (day 1 to 3 postoperatively). Secondary outcomes will be cumulative dynamic pain score preoperatively, cumulative side effects, cumulative calorific and protein intake, EUROQOL EQ-5D score, length of stay, and rehabilitation outcome (measured by mobility score). Discussion Many studies have shown the effectiveness of regional blockade in neck of femur fractures, but the techniques used have varied. This study aims to identify whether early and continuous femoral nerve block can be effective in relieving pain and enhancing mobilization

  12. Ultrasound Guided Transversus Abdominis Plane Block for Anterior Cutaneous Nerve Entrapment Syndrome.

    PubMed

    Sahoo, Rajendra Kumar; Nair, Abhijit S

    2015-10-01

    Anterior cutaneous nerve entrapment syndrome (ACNES) is one the most common cause of chronic abdominal wall pain. The syndrome is mostly misdiagnosed, treated wrongly and inadequately. If diagnosed correctly by history, examination and a positive carnett test, the suffering of the patient can be relieved by addressing the cause i.e. local anaesthetic with steroid injection at the entrapment site. Conventionally, the injection is done by landmark technique. In this report, we have described 2 patients who were diagnosed with ACNES who were offered ultrasound guided transverses abdominis plane (TAP) injection who got significant pain relief for a long duration of time. PMID:26495084

  13. Significance of localization of mandibular foramen in an inferior alveolar nerve block

    PubMed Central

    Thangavelu, K.; Kannan, R.; Kumar, N. Senthil; Rethish, E.; Sabitha, S.; SayeeGanesh, N.

    2012-01-01

    Background: The mandibular foramen (MF) is an opening on the internal surface of the ramus for divisions of the mandibular vessels and nerve to pass. The aim of this study is to determine the position of the MF from various anatomical landmarks in several dry adult mandibles. Materials and Methods: A total of 102 human dry mandibles were examined, of which 93 were of dentulous and 9 were of edentulous. The measurements were taken from the anterior border of the ramus (coronoid notch) to the midportion of the MF and then from the midportion of the MF to the other landmarks such as internal oblique ridge, inferior border, sigmoid notch, and condyle were measured and recorded. Results: The data were compared using Student's t-test. The MF is positioned at a mean distance of 19 mm (with SD 2.34) from coronoid notch of the anterior border of the ramus. Superio-inferiorly from the condyle to the inferior border MF is situated 5 mm inferior to the midpoint of condyle to the inferior border distance (ramus height). Conclusion: We conclude that failures in the anesthesia of the inferior alveolar nerve are due to the operator error and not due to the anatomical variation. PMID:23225978

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

    PubMed Central

    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

  15. Minimum effective local anesthetic volume for surgical anesthesia by subparaneural, ultrasound-guided popliteal sciatic nerve block: A prospective dose-finding study.

    PubMed

    Bang, Seung Uk; Kim, Dong Ju; Bae, Jin Ho; Chung, Kyudon; Kim, Yeesuk

    2016-08-01

    Because of its rapid onset time, recent years have seen an increase in the use of ultrasound (US)-guided popliteal sciatic nerve block (PSNB) via subparaneural injection for induction of surgical anesthesia. Moreover, in below-knee surgery, combined blocks, as opposed to sciatic nerve block alone, have become more common. These combined blocks often require a large volume of local anesthetic (LA), thus increasing the risk of local-anesthetic systemic toxicity (LAST). Thus, to decrease the risk of LAST, it is important to know the minimum effective volume (MEV) required for an adequate block. We, therefore, aimed to determine the MEV of ropivacaine 0.75% for induction of surgical anesthesia by the method of US-guided popliteal sciatic nerve block via subparaneural injection.Thirty patients underwent a US-guided PSNB with ropivacaine 0.75% at a 20-mL starting volume. Using a step-up/step-down method, we determined injection volumes for consecutive patients from the preceding patient's outcome. When an effective block was achieved within 40 minutes after injection, the next patient's volume was decreased by 2 mL. If the block failed, the next patient's volume was increased by 2 mL. The sensory and motor blockade was graded according to a 4-point scale. The block was considered a success if a combination of anesthesia and paresis (a score of 3 for both the sensory and motor nerves) was achieved within 40 minutes. The primary outcome measure was the MEV resulting in a successful subparaneural block of the sciatic nerve in 50% of patients (MEV50). Additionally, the data were processed with a probit regression analysis to determine the volume required to produce a complete sciatic nerve block in 90% of subjects (ED90).The MEV50 of 0.75% ropivacaine is 6.14 mL (95% confidence interval, 4.33-7.94 mL). The ED90 by probit analysis for a subparaneural injection was 8.9 mL (95% CI, 7.09-21.75 mL).The 6.14-mL MEV50 of ropivacaine 0.75% represents a 71% reduction

  16. Surgery versus Nerve Blocks for Lumbar Disc Herniation : Quantitative Analysis of Radiological Factors as a Predictor for Successful Outcomes

    PubMed Central

    Kim, Joohyun; Hur, Junseok W.; Lee, Jang-Bo

    2016-01-01

    Objective To assess the clinical and radiological factors as predictors for successful outcomes in lumbar disc herniation (LDH) treatment. Methods Two groups of patients with single level LDH (L4–5) requiring treatment were retrospectively studied. The surgery group (SG) included 34 patients, and 30 patients who initially refused the surgery were included in the nerve blocks group (NG). A visual analogue scale (VAS) for leg and back pain and motor deficit were initially evaluated before procedures, and repeated at 1, 6, and 12 months. Radiological factors including the disc herniation length, disc herniation area, canal length-occupying ratio, and canal area-occupying ratio were measured and compared. Predicting factors of successful outcomes were determined with multivariate logistic regression analysis after the optimal cut off values were established with a receiver operating characteristic curve. Results There was no significant demographic difference between two groups. A multivariate logistic regression analysis with radiological and clinical (12 months follow-up) data revealed that the high disc herniation length with cutoff value 6.31 mm [odds ratio (OR) 2.35; confidence interval (CI) 1.21–3.98] was a predictor of successful outcomes of leg pain relief in the SG. The low disc herniation length with cutoff value 6.23 mm (OR 0.05; CI 0.003–0.89) and high baseline VAS leg (OR 12.63; CI 1.64–97.45) were identified as predictors of successful outcomes of leg pain relief in the NG. Conclusion The patients with the disc herniation length larger than 6.31 mm showed successful outcomes with surgery whereas the patients with the disc herniation length less than 6.23 mm showed successful outcomes with nerve block. These results could be considered as a radiological criteria in choosing optimal treatment options for LDH. PMID:27651866

  17. Surgery versus Nerve Blocks for Lumbar Disc Herniation : Quantitative Analysis of Radiological Factors as a Predictor for Successful Outcomes

    PubMed Central

    Kim, Joohyun; Hur, Junseok W.; Lee, Jang-Bo

    2016-01-01

    Objective To assess the clinical and radiological factors as predictors for successful outcomes in lumbar disc herniation (LDH) treatment. Methods Two groups of patients with single level LDH (L4–5) requiring treatment were retrospectively studied. The surgery group (SG) included 34 patients, and 30 patients who initially refused the surgery were included in the nerve blocks group (NG). A visual analogue scale (VAS) for leg and back pain and motor deficit were initially evaluated before procedures, and repeated at 1, 6, and 12 months. Radiological factors including the disc herniation length, disc herniation area, canal length-occupying ratio, and canal area-occupying ratio were measured and compared. Predicting factors of successful outcomes were determined with multivariate logistic regression analysis after the optimal cut off values were established with a receiver operating characteristic curve. Results There was no significant demographic difference between two groups. A multivariate logistic regression analysis with radiological and clinical (12 months follow-up) data revealed that the high disc herniation length with cutoff value 6.31 mm [odds ratio (OR) 2.35; confidence interval (CI) 1.21–3.98] was a predictor of successful outcomes of leg pain relief in the SG. The low disc herniation length with cutoff value 6.23 mm (OR 0.05; CI 0.003–0.89) and high baseline VAS leg (OR 12.63; CI 1.64–97.45) were identified as predictors of successful outcomes of leg pain relief in the NG. Conclusion The patients with the disc herniation length larger than 6.31 mm showed successful outcomes with surgery whereas the patients with the disc herniation length less than 6.23 mm showed successful outcomes with nerve block. These results could be considered as a radiological criteria in choosing optimal treatment options for LDH.

  18. Role of sympathetic nerve activity in the process of fainting

    PubMed Central

    Iwase, Satoshi; Nishimura, Naoki; Mano, Tadaaki

    2014-01-01

    Syncope is defined as a transient loss of consciousness and postural tone, characterized by rapid onset, short duration, and spontaneous recovery, and the process of syncope progression is here described with two types of sympathetic change. Simultaneous recordings of microneurographically-recorded muscle sympathetic nerve activity (MSNA) and continuous and noninvasive blood pressure measurement has disclosed what is going on during the course of syncope progression. For vasovagal or neurally mediated syncope, three stages are identified in the course of syncope onset, oscillation, imbalance, and catastrophe phases. Vasovagal syncope is characterized by sympathoexcitation, followed by vagal overcoming via the Bezold-Jarisch reflex. Orthostatic syncope is caused by response failure or a lack of sympathetic nerve activity to the orthostatic challenge, followed by fluid shift and subsequent low cerebral perfusion. Four causes are considered for the compensatory failure that triggers orthostatic syncope: hypovolemia, increased pooling in the lower body, failure to activate sympathetic activity, and failure of vasoconstriction against sympathetic vasoconstrictive stimulation. Many pathophysiological conditions have been described from the perspectives of (1) exaggerated sympathoexcitation and (2) failure to activate the sympathetic nerve. We conclude that the sympathetic nervous system can control cardiovascular function, and its failure results in syncope; however, responses of the system obtained by microneurographically-recorded MSNA would determine the pathophysiology of the onset and progression of syncope, explaining the treatment effect that could be achieved by the analysis of this mechanism. PMID:25309444

  19. Ultrasound-Guided Femoral and Sciatic Nerve Blocks for Repair of Tibia and Fibula Fractures in a Bennett's Wallaby (Macropus rufogriseus)

    PubMed Central

    Campoy, Luis; Adami, Chiara

    2016-01-01

    Locoregional anesthetic techniques may be a very useful tool for the anesthetic management of wallabies with injuries of the pelvic limbs and may help to prevent capture myopathies resulting from stress and systemic opioids' administration. This report describes the use of ultrasound-guided femoral and sciatic nerve blocks in Bennett's wallaby (Macropus rufogriseus) referred for orthopaedic surgery. Ultrasound-guided femoral and sciatic nerve blocks were attempted at the femoral triangle and proximal thigh level, respectively. Whilst the sciatic nerve could be easily visualised, the femoral nerve could not be readily identified. Only the sciatic nerve was therefore blocked with ropivacaine, and methadone was administered as rescue analgesic. The ultrasound images were stored and sent for external review. Anesthesia and recovery were uneventful and the wallaby was discharged two days postoperatively. At the time of writing, it is challenging to provide safe and effective analgesia to Macropods. Detailed knowledge of the anatomy of these species is at the basis of successful locoregional anesthesia. The development of novel analgesic techniques suitable for wallabies would represent an important step forward in this field and help the clinicians dealing with these species to improve their perianesthetic management. PMID:27803817

  20. The Patterns of Utilization of Interscalene Nerve Blocks for Total Shoulder Arthroplasty.

    PubMed

    Gabriel, Rodney A; Nagrebetsky, Alexander; Kaye, Alan D; Dutton, Richard P; Urman, Richard D

    2016-09-01

    The interscalene block (ISB) is a common adjunct to general anesthesia for total shoulder arthroplasty (TSA). The aim of the study was to report the current national demographics of the patients who are receiving ISB for TSAs. We performed a retrospective analysis of data from the National Anesthesia Clinical Outcomes Registry from 2010 to 2015. Of 28,810 cases, 42.1% received an ISB. Only 0.83% of cases received regional anesthesia as the primary anesthetic. From 2010 to 2014, there has been an increase in ISB utilization for this surgery (odds ratio, 1.21; 95% confidence interval, 1.19-1.23; P < .0001). Furthermore, we report a geographic distribution of block utilization in the United States. We have identified national patterns for the utilization of regional anesthesia for TSAs that may provide insight into future design of research studies. PMID:27537763

  1. Continuous epidural block versus continuous popliteal nerve block for postoperative pain relief after major podiatric surgery in children: a prospective, comparative randomized study.

    PubMed

    Dadure, Christophe; Bringuier, Sophie; Nicolas, Florence; Bromilow, Luke; Raux, Olivier; Rochette, Alain; Capdevila, Xavier

    2006-03-01

    Foot and ankle surgery in children is very painful postoperatively. Adverse effects from opioids and continuous epidural block (CEB) limit their use in children. Continuous popliteal nerve blocks (CPNB) have not been studied for this indication in children. In this prospective, randomized study we evaluated the effectiveness and adverse events of CPNB or CEB in children after podiatric surgery. Fifty-two children scheduled for foot surgery were separated into four groups by age and analgesia technique. After general anesthesia, 0.5 to 1 mL/kg of an equal-volume mixture of 0.25% bupivacaine and 1% lidocaine with 1:200000 epinephrine was injected via epidural or popliteal catheters. In the postoperative period, 0.1 mL x kg(-1) x h(-1) (group CPNB) or 0.2 mL x kg(-1) x h(-1) (group CEB) of 0.2% ropivacaine was administered for 48 h. Niflumic acid was routinely used. Adverse events were noted in each treatment group. Postoperative pain during motion was evaluated at 1, 6, 12, 18, 24, 36, and 48 h. Requirement for rescue analgesia (first-line propacetamol 30 mg/kg 4 times daily or second-line 0.2 mg/kg IV nalbuphine), and motor blockade were recorded. Parental satisfaction was noted at 48 h. Twenty-seven patients were included in the CEB groups and 25 in CPNB groups. There were 32 children 1 to 6 yr of age (CPNB = 15; CEB = 17) and 20 children 7 to 12 yr of age (CPNB = 10; CEB = 10). The demographic data were comparable among groups. Postoperative analgesia was excellent for the two continuous block techniques and in the two age groups. Motor block intensity was equal between techniques. Adverse events (postoperative nausea or vomiting, urinary retention, and premature discontinuation of local anesthetic infusion in the 1- to 6-yr-old group) were significantly more frequent in the CEB group (P < 0.05). Eighty-six percent of the parents in the CEB groups and 100% in the CPNB groups were satisfied. We conclude that although both CEB and CPNB resulted in excellent

  2. Essential Oil of Ocimum basilicum L. and (−)-Linalool Blocks the Excitability of Rat Sciatic Nerve

    PubMed Central

    Medeiros Venancio, Antonio; da Silva-Alves, Kerly Shamyra; de Carvalho Pimentel, Hugo; Macêdo Lima, Matheus; Fraga de Santana, Michele; Batista da Silva, Givanildo; Marchioro, Murilo

    2016-01-01

    The racemate linalool and its levogyrus enantiomer [(−)-LIN] are present in many essential oils and possess several pharmacological activities, such as antinociceptive and anti-inflammatory. In this work, the effects of essential oil obtained from the cultivation of the Ocimum basilicum L. (EOOb) derived from Germplasm Bank rich in (−)-LIN content in the excitability of peripheral nervous system were studied. We used rat sciatic nerve to investigate the EOOb and (−)-LIN effects on neuron excitability and the extracellular recording technique was used to register the compound action potential (CAP). EOOb and (−)-LIN blocked the CAP in a concentration-dependent way and these effects were reversible after washout. EOOb blocked positive amplitude of 1st and 2nd CAP components with IC50 of 0.38 ± 0.2 and 0.17 ± 0.0 mg/mL, respectively. For (−)-LIN, these values were 0.23 ± 0.0 and 0.13 ± 0.0 mg/mL. Both components reduced the conduction velocity of CAP and the 2nd component seems to be more affected than the 1st component. In conclusion EOOb and (−)-LIN inhibited the excitability of peripheral nervous system in a similar way and potency, revealing that the effects of EOOb on excitability are due to the presence of (−)-LIN in the essential oil. PMID:27446227

  3. Postsurgical compartment syndrome of the forearm diagnosed in a child receiving a continuous infra-clavicular peripheral nerve block.

    PubMed

    Sermeus, L; Boeckx, S; Camerlynck, H; Somville, J; Vercauteren, M

    2015-01-01

    Opinions diverge as to whether or not regional anaesthesia delays the diagnosis of evolving acute compartment syndrome. Withholding regional anaesthesia from patients with painful orthopaedic injuries may be ethically unacceptable, however. In this report, we describe a case of acute compartment syndrome in a 4-year old child who underwent resection of a forearm osteochondroma. Analgesia was satisfactory during the first post-operative night, but the child later complained of pain despite an effective infra-clavicular block. Motor function and sensibility were disturbed and the fingers were swollen. The forearm cast was removed as it was suspected to be causing external compression. Pain disappeared while motor function and sensation recovered. The child was discharged without any complications. Despite an effective peripheral nerve block and the young age of the patient, the diagnosis of acute compartment syndrome could be made thanks to a well-defined post-operative analgesia protocol, a high level of suspicion and careful clinical assessment when break-through pain occurred.

  4. The Position of Lingula as an Index for Inferior Alveolar Nerve Block Injection in 7-11-Year-Old Children

    PubMed Central

    Ezoddini Ardakani, Fatemeh; Bahrololoumi, Zahra; Zangouie Booshehri, Maryam; Navab Azam, Alireza; Ayatollahi, Fatemeh

    2010-01-01

    Background and aims Inferior alveolar nerve block injection is one of the common intra oral anesthetic techniques, with a failure rate of 15-20%. The aim of this study was to evaluate the position of the lingula as an index for this injection. Materials and methods Thirty eight panoramic radiographs of 7–11 year old patients were analyzed and the distance between the lingula index and occlusal plane was measured. Then, lower alveolar nerve block injection was performed on 88 children. Finally, a visual analogue scale was used to measure the rate of pain in the patients. Results This distance increased with age and in children younger than nine years is −0.45 mm on the right side and −0.95 mm on the left side. This distance in children older than 9 years is −0.23 mm on the right side and 0.47 mm on the left side. The success rates of inferior alveolar nerve block injection based on lingual index were 49% on the right side and 53.8% on the left side. Conclusion As the lingual index has various positions and its distance from the occlusal plane increases with age, it is not an appropriate landmark for inferior alveolar nerve block injection. PMID:22991596

  5. Surface biology of collagen scaffold explains blocking of wound contraction and regeneration of skin and peripheral nerves.

    PubMed

    Yannas, I V; Tzeranis, D; So, P T

    2015-12-23

    We review the details of preparation and of the recently elucidated mechanism of biological (regenerative) activity of a collagen scaffold (dermis regeneration template, DRT) that has induced regeneration of skin and peripheral nerves (PN) in a variety of animal models and in the clinic. DRT is a 3D protein network with optimized pore size in the range 20-125 µm, degradation half-life 14 ± 7 d and ligand densities that exceed 200 µM α1β1 or α2β1 ligands. The pore has been optimized to allow migration of contractile cells (myofibroblasts, MFB) into the scaffold and to provide sufficient specific surface for cell-scaffold interaction; the degradation half-life provides the required time window for satisfactory binding interaction of MFB with the scaffold surface; and the ligand density supplies the appropriate ligands for specific binding of MFB on the scaffold surface. A dramatic change in MFB phenotype takes place following MFB-scaffold binding which has been shown to result in blocking of wound contraction. In both skin wounds and PN wounds the evidence has shown clearly that contraction blocking by DRT is followed by induction of regeneration of nearly perfect organs. The biologically active structure of DRT is required for contraction blocking; well-matched collagen scaffold controls of DRT, with structures that varied from that of DRT, have failed to induce regeneration. Careful processing of collagen scaffolds is required for adequate biological activity of the scaffold surface. The newly understood mechanism provides a relatively complete paradigm of regenerative medicine that can be used to prepare scaffolds that may induce regeneration of other organs in future studies.

  6. Fentanyl Patches to Supplement Ultrasound-Guided Nerve Blocks for Improving Pain Control After Foot and Ankle Surgery: A Prospective Study.

    PubMed

    Song, Jae-Hwang; Kang, Chan; Hwang, Deuk-Soo; Hwang, Jung-Mo; Shin, Byung-Kon

    2016-01-01

    The analgesic effects of preoperative ultrasound-guided nerve blocks wear off after about 12 hours, leaving some patients in substantial pain. Transdermal fentanyl concentrations peak at 12 to 24 hours after application and maintain this concentration for approximately 72 hours. We sought to determine whether combining the use of a transdermal fentanyl patch with either a sciatic or femoral-sciatic nerve block would improve pain control in patients undergoing foot and/or ankle surgery. Consecutive patients in the no-patch control group (n = 104) were enrolled from July 2011 to October 2011, and those in the treatment group (n = 232) were enrolled from November 2011 to May 2012 and received a transdermal patch (4.125 mg/7.5 cm(2) releasing 25 μg of fentanyl per hour) applied to their chest postoperatively. Pain was assessed using a visual analog scale at 6, 12, 24, and 48 hours after surgery. The primary outcome measure was the number of requests for additional postoperative pain medication. Additional postoperative analgesia was requested by 49 of the 104 control patients (47.1%) and 63 of the 232 treated patients (27.1%; p = .002). The mean pain scores were also lower in the treatment group, with a statistically significant difference (p < .05) at 12, 24, and 48 hours. Thus, patients receiving a fentanyl patch combined with an ultrasound-guided nerve block required less supplemental analgesia to maintain adequate pain control than did those receiving a nerve block alone. In conclusion, a fentanyl patch is a useful adjunct to an ultrasound-guided nerve block in foot and ankle surgery.

  7. The role of autophagy in axonal degeneration of the optic nerve.

    PubMed

    Koch, Jan Christoph; Lingor, Paul

    2016-03-01

    Different pathological conditions including glaucoma, optic neuritis, hereditary optic atrophy and traumatic injury lead to a degeneration of retinal ganglion cell axons in the optic nerve. Besides this clinical relevance, several experimental models employ the optic nerve as a model system to examine general mechanisms of axonal degeneration in the central nervous system. Several experimental studies have demonstrated that an activation of autophagy is a prominent feature of axonal degeneration in the optic nerve independent of the underlying pathological condition. However, the function of autophagy in axonal degeneration remains still unclear. Inhibition of autophagy was found to attenuate axonal degeneration within the first hours after optic nerve lesion. Other studies focusing on survival of retinal ganglion cells at later postlesional time points report contradicting results, where both inhibition and induction of autophagy were beneficial for survival, depending on the model system or examination time. Therefore, a more precise understanding of the role and the kinetics of autophagy in axonal degeneration is mandatory to develop new therapies for diseases of the optic nerve. Here, we review the literature on the pathophysiological role of autophagy in axonal degeneration in the optic nerve and discuss its implications for future therapeutic approaches in diseases of the eye and the central nervous system involving axonal degeneration.

  8. Arachidonic Acid Derivatives and Their Role in Peripheral Nerve Degeneration and Regeneration

    PubMed Central

    Camara-Lemarroy, Carlos Rodrigo; Gonzalez-Moreno, Emmanuel Irineo; Guzman-de la Garza, Francisco Javier; Fernandez-Garza, Nancy Esthela

    2012-01-01

    After peripheral nerve injury, a process of axonal degradation, debris clearance, and subsequent regeneration is initiated by complex local signaling, called Wallerian degeneration (WD). This process is in part mediated by neuroglia as well as infiltrating inflammatory cells and regulated by inflammatory mediators such as cytokines, chemokines, and the activation of transcription factors also related to the inflammatory response. Part of this neuroimmune signaling is mediated by the innate immune system, including arachidonic acid (AA) derivatives such as prostaglandins and leukotrienes. The enzymes responsible for their production, cyclooxygenases and lipooxygenases, also participate in nerve degeneration and regeneration. The interactions between signals for nerve regeneration and neuroinflammation go all the way down to the molecular level. In this paper, we discuss the role that AA derivatives might play during WD and nerve regeneration, and the therapeutic possibilities that arise. PMID:22997489

  9. Glans ischemia after circumcision and dorsal penile nerve block: Case report and review of the literature

    PubMed Central

    Garrido-Abad, Pablo; Suárez-Fonseca, Carlos

    2015-01-01

    Circumcision is an easy commonly performed surgical procedure in childhood. However, it is not free of a low number of complications, (1-5-5%). Here we report a case of a 3-year-old boy with glans superficial necrosis after circumcision, managed with topical (nitroglycerin, gentamicin), oral (pentoxifylline) and epidural (urgent caudal block with bupivacaine) treatment. A review of the literature and the different treatments reported by other authors was done. After 7 days of treatment, local signs of ischemia and severe pain disappeared, without adverse events related to treatment. Although the ischemia or necrosis of the glans after circumcision are rare, we may suspect them in case of presence of severe acute pain or dark color. We report the successful management of this complication. PMID:26692685

  10. Perineural Dexmedetomidine as an Adjuvant Reduces the Median Effective Concentration of Lidocaine for Obturator Nerve Blocking: A Double-Blinded Randomized Controlled Trial

    PubMed Central

    Lu, Yuechun; Sun, Jian; Zhuang, Xinqi; Lv, Guoyi; Li, Yize; Wang, Haiyun; Wang, Guolin

    2016-01-01

    Research suggests that the addition of dexmedetomidine to local anesthetics can prolong peripheral nerve blocks; however, it is not known whether dexmedetomidine can reduce the quantity of local anesthetic needed. We hypothesized that adding dexmedetomidine as an adjuvant to an obturator nerve block could reduce the median effective concentration of lidocaine. In this double-blinded randomized trial, 60 patients scheduled for elective transurethral resection of bladder tumors on the lateral wall were randomly divided into two groups: the control group (C group, n = 30) and the dexmedetomidine group (D group, n = 30). Two main branches of the obturator nerve (i.e., anterior and posterior) were identified using neural stimulation at the inguinal level, with only lidocaine used for the C group and 1 μg/kg dexmedetomidine combined with lidocaine used for the D group. The median effective concentration was determined by an up-and-down sequential trial. The ratio of two consecutive concentrations was 1.2. The median effective concentration (95% confidence interval) of lidocaine was 0.57% (0.54%-0.62%) in the C group and 0.29% (0.28%-0.38%) in the D group. The median effective concentration of lidocaine was significantly lower in the D group than in the C group (p < 0.05). These results indicate that dexmedetomidine (1 μg/kg) in combination with lidocaine for obturator nerve block decreases the median effective concentration of lidocaine. Trial Registration: ClinicalTrials.gov NCT02066727 PMID:27341450

  11. Guidance of Block Needle Insertion by Electrical Nerve Stimulation: A Pilot Study of the Resulting Distribution of Injected Solution in Dogs

    PubMed Central

    Rigaud, Marcel; Filip, Patrick; Lirk, Philipp; Fuchs, Andreas; Gemes, Geza; Hogan, Quinn

    2009-01-01

    Background Little is known regarding the final needle tip location when various intensities of nerve stimulation are used to guide block needle insertion. Therefore, in control and hyperglycemic dogs, the authors examined whether lower-intensity stimulation results in injection closer to the sciatic nerve than higher-threshold stimulation. Methods During anesthesia, the sciatic nerve was approached with an insulated nerve block needle emitting either 1 mA (high-current group, n = 9) or 0.5 mA (low-current group, n = 9 in control dogs and n = 6 in hyperglycemic dogs). After positioning to obtain a distal motor response, the lowest current producing a response was identified, and ink (0.5 ml) was injected. Frozen sections of the tissue revealed whether the ink was in contact with the epineurium of the nerve, distant to it, or within it. Results In control dogs, the patterns of distribution using high-threshold (final current 0.99 ± 0.03 mA, mean ± SD) and low-threshold (final current 0.33 ± 0.08 mA) stimulation equally showed ink that was in contact with the epineurium or distant to it. One needle placement in the high-threshold group resulted in intraneural injection. In hyperglycemic dogs, all needle insertions used a low-threshold technique (n = 6, final threshold 0.35 ± 0.08 mA), and all resulted in intraneural injections. Conclusions In normal dogs, current stimulation levels in the range of 0.33–1.0 mA result in needle placement comparably close to the sciatic nerve but do not correlate with distance from the target nerve. In this experimental design, low-threshold electrical stimulation does not offer satisfactory protection against intraneural injection in the presence of hyperglycemia. PMID:18719445

  12. Role of sensory nerves in the cutaneous vasoconstrictor response to local cooling in humans.

    PubMed

    Hodges, Gary J; Traeger, J Andrew; Tang, Tri; Kosiba, Wojciech A; Zhao, Kun; Johnson, John M

    2007-07-01

    Local cooling (LC) causes a cutaneous vasoconstriction (VC). In this study, we tested whether there is a mechanism that links LC to VC nerve function via sensory nerves. Six subjects participated. Local skin and body temperatures were controlled with Peltier probe holders and water-perfused suits, respectively. Skin blood flow at four forearm sites was monitored by laser-Doppler flowmetry with the following treatments: untreated control, pretreatment with local anesthesia (LA) blocking sensory nerve function, pretreatment with bretylium tosylate (BT) blocking VC nerve function, and pretreatment with both LA and BT. Local skin temperature was slowly reduced from 34 to 29 degrees C at all four sites. Both sites treated with LA produced an increase in cutaneous vascular conductance (CVC) early in the LC process (64 +/- 55%, LA only; 42 +/- 14% LA plus BT; P < 0.05), which was absent at the control and BT-only sites (5 +/- 8 and 6 +/- 8%, respectively; P > 0.05). As cooling continued, there were significant reductions in CVC at all sites (P < 0.05). At control and LA-only sites, CVC decreased by 39 +/- 4 and 46 +/- 8% of the original baseline values, which were significantly (P < 0.05) more than the reductions in CVC at the sites treated with BT and BT plus LA (-26 +/- 8 and -22 +/- 6%). Because LA affected only the short-term response to LC, either alone or in the presence of BT, we conclude that sensory nerves are involved early in the VC response to LC, but not for either adrenergic or nonadrenergic VC with longer term LC.

  13. A population pharmacokinetic model for the complex systemic absorption of ropivacaine after femoral nerve block in patients undergoing knee surgery.

    PubMed

    Gaudreault, François; Drolet, Pierre; Fallaha, Michel; Varin, France

    2012-12-01

    Because of its slow systemic absorption and flip-flop kinetics, ropivacaine's pharmacokinetics after a peripheral nerve block has never been thoroughly characterized. The purpose of this study was to develop a population pharmacokinetic model for ropivacaine after loco-regional administration and to identify patient characteristics that may influence the drug's absorption and disposition. Frequent plasma samples were taken up to 93 h after a 100 mg dose given as femoral block for postoperative analgesia in 15 orthopedic patients. Ropivacaine plasma concentration-time data were analyzed using a nonlinear mixed effects modeling method. A one-compartment model with parallel inverse Gaussian and time-dependent inputs best described ropivacaine plasma concentration-time curves. Ropivacaine systemic absorption was characterized by a rapid phase (mean absorption time of 25 ± 4.8 min) followed by a much slower phase (half-life of 3.9 ± 0.65 h). Interindividual variability (IIV) for these parameters, 58 and 9 %, indicated that the initial absorption phase was more variable. The apparent volume of distribution (V/F = 77.2 ± 11.5 L, IIV = 26 %) was influenced by body weight (Δ 1.49 % per kg change) whereas the absorption rate constant (slower phase) of ropivacaine was affected by age (Δ 2.25 % per year change). No covariate effects were identified for the apparent clearance of the drug (CL/F =10.8 ± 1.0 L/h, 34  IIV = 34 %). These findings support our hypothesis that modeling a complex systemic absorption directly from plasma concentration-time curves exhibiting flip-flop kinetics is possible. Only the age-effect was considered as relevant for possible dosing adjustments.

  14. Cold bupivacaine versus magnesium sulfate added to room temperature bupivacaine in sonar-guided femoral and sciatic nerve block in arthroscopic anterior cruciate ligament reconstruction surgery

    PubMed Central

    Alzeftawy, Ashraf Elsayed; El-Daba, Ahmad Ali

    2016-01-01

    Background: Cooling of local anesthetic potentiates its action and increases its duration. Magnesium sulfate (MgSo4) added to local anesthetic prolongs the duration of anesthesia and postoperative analgesia with minimal side effects. Aim: The aim of this prospective, randomized, double-blind study was to compare the effect of cold to 4°C bupivacaine 0.5% and Mg added to normal temperature (20–25°C) bupivacaine 0.5% during sonar-guided combined femoral and sciatic nerve blocks on the onset of sensory and motor block, intraoperative anesthesia, duration of sensory and motor block, and postoperative analgesia in arthroscopic anterior cruciate ligament (ACL) reconstruction surgery. Patients and Methods: A total of 90 American Society of Anesthesiologists classes I and II patients who were scheduled to undergo elective ACL reconstruction were enrolled in the study. The patients were randomly allocated to 3 equal groups to receive sonar-guided femoral and sciatic nerve blocks. In Group I, 17 ml of room temperature (20–25°C) 0.5% bupivacaine and 3 ml of room temperature saline were injected for each nerve block whereas in Group II, 17 ml of cold (4°C) 0.5% bupivacaine and 3 ml of cold saline were injected for each nerve block. In Group III, 17 ml of room temperature 0.5% bupivacaine and 3 ml of MgSo4 5% were injected for each nerve block. The onset of sensory and motor block was evaluated every 3 min for 30 min. Surgery was started after complete sensory and motor block were achieved. Intraoperatively, the patients were evaluated for heart rate and mean arterial pressure, rescue analgesic and sedative requirements plus patient and surgeon satisfaction. Postoperatively, hemodynamics, duration of analgesia, resolution of motor block, time to first analgesic, total analgesic consumption, and the incidence of side effects were recorded. Results: There was no statistically significant difference in demographic data, mean arterial pressure, heart rate, and duration of

  15. Sympathetic sprouting near sensory neurons after nerve injury occurs preferentially on spontaneously active cells and is reduced by early nerve block

    PubMed Central

    Xie, Wenrui; Strong, Judith Ann; Li, Huiqing; Zhang, Jun-Ming

    2006-01-01

    Some chronic pain conditions are maintained or enhanced by sympathetic activity. In animal models of pathological pain, abnormal sprouting of sympathetic fibers around large- and medium-size sensory neurons is observed in dorsal root ganglia (DRG). Large and medium size cells are also more likely to be spontaneously active, suggesting that sprouting may be related to neuron activity. We previously showed that sprouting could be reduced by systemic or locally applied lidocaine. In the complete sciatic nerve transection model in rats, spontaneous activity initially originates in the injury site; later, the DRG become the major source of spontaneous activity. In this study, spontaneous activity reaching the DRG soma was reduced by early nerve blockade (local perfusion of the transected nerve with TTX for the first 7 days after injury). This significantly reduced sympathetic sprouting. Conversely, increasing spontaneous activity by local nerve perfusion with K+ channel blockers increased sprouting. The hyperexcitability and spontaneous activity of DRG neurons observed in this model were also significantly reduced by early nerve blockade. These effects of early nerve blockade on sprouting, excitability, and spontaneous activity were all observed 4 to 5 weeks after the end of early nerve blockade, indicating that the early period of spontaneous activity in the injured nerve is critical for establishing the more long-lasting pathologies observed in the DRG. Individual spontaneously active neurons, labeled with fluorescent dye, were 5–6 times more likely than quiescent cells to be co-localized with sympathetic fibers, suggesting a highly localized correlation of activity and sprouting. PMID:17065247

  16. The potential role of nerve growth factor in cryoneurolysis-induced neuropathic pain in rats.

    PubMed

    Ju, Hui; Feng, Yi; Gao, Zhifeng; Yang, Ba-Xian

    2012-10-01

    Cryoanalgesia is suggested as a risk factor of neuropathic pain. The current study investigated the pain behavior of sciatic nerve cryoneurolysis (SCN) in adult male rats. The role of nerve growth factor (NGF) was also studied. The mechanical threshold was significantly elevated in SCN group than sham-operation group within 14days after surgery. After 28days, 22 out of 39 SCN rats (56.4%) represented mechanical hyperalgesia. There were much more NGF-immunoreactive nerve cells expressed in the dorsal horn in SCN rats with hyperalgesia. The NGF protein levels of SCN rats measured by Western blot were higher than sham-operation rats, while they were significantly higher in SCN rats with hyperalgesia than those without hyperalgesia. Pain-related behavior improved after anti-NGF treatment, compared with vehicle control group. NGF is associated with SCN-induced neuropathic pain. Peripherally secreted NGF may play an important role in this mechanism. PMID:22580175

  17. Towards evidence-based emergency medicine: best BETs from the Manchester Royal Infirmary. BET 2: does magnesium prolong the analgaesic effect of bupivacaine in a fascia iliaca nerve block?

    PubMed

    Kilgour, Peter; Oni, Babajide; Ghanayem, Hisham; Tabone, Dianne

    2015-05-01

    A shortcut review was carried out to establish whether routine use of magnesium as an adjunct to bupivacaine fascia iliaca nerve block in femoral neck fracture was effective in prolonging its analgaesic effect. Forty-four papers were found using the reported searches, of which one presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of this paper are tabulated. It is concluded that while magnesium has the potential to prolong the analgaesic effect of bupivacaine further studies are needed to clarify its exact role and safety profile.

  18. Treatment outcomes of intradiscal steroid injection/selective nerve root block for 161 patients with cervical radiculopathy.

    PubMed

    Ito, Keigo; Yukawa, Yasutsugu; Machino, Masaaki; Inoue, Taro; Ouchida, Jun; Tomita, Keisuke; Kato, Fumihiko

    2015-02-01

    Patients with cervical radiculopathy (CR) were treated with intradiscal injection of steroids (IDIS) and/or selective nerve root block (SNRB) at our hospital. We retrospectively report the outcomes of these nonsurgical treatments for CR. 161 patients who were followed up for >2months were enrolled in this study. Patients' clinical manifestations were classified as arm pain, arm numbness, neck and/or scapular pain, and arm paralysis. Improvement in each manifestation was classified as "disappeared," "improved," "poor," or "worsened." Responses of "disappeared" or "improved" manifestations suggested treatment effectiveness. Final clinical outcomes were evaluated using the Odom criteria. Changes in herniated disc size were evaluated by comparing the initial and final MRI scans. On the basis of these changes, the patients were divided into regression, no-change, or progression groups. We investigated the relationship between the Odom criteria and changes observed on MRI. Effectiveness rates were 89% for arm pain, 77% for arm numbness, 82% for neck and/or scapular pain, and 76% for arm paralysis. In total, 91 patients underwent repeated MRI. In 56 patients (62%), the size of the herniated disc decreased, but 31 patients (34%) exhibited no change in disc size. The regression group showed significantly better Odom criteria results than the no-change group. In conclusion, IDIS and SNRB for CR are not widely performed. However, other extremely effective therapies that can rapidly improve neuralgia should be considered before surgery. PMID:25797986

  19. A comparative study of three techniques for diameter selective fiber activation in the vagal nerve: anodal block, depolarizing prepulses and slowly rising pulses

    NASA Astrophysics Data System (ADS)

    Vuckovic, Aleksandra; Tosato, Marco; Struijk, Johannes J.

    2008-09-01

    The paper shows selective smaller fiber activation in the left and right vagal nerve in in vivo experiments in pigs using three different techniques: anodal block, depolarizing prepulses and slowly rising pulses. All stimulation techniques were performed with the same experimental setup. The techniques have been compared in relation to maximum achievable suppression of nerve activity, maximum required current, maximum achievable stimulation frequency and the required charge per phase. Suppression of the largest fiber activity (expressed as a percentage of the maximum response) was 0-40% for anodal block, 10-25% for depolarizing prepulses and 40-50% for slowly rising pulses (duration up to 5 ms). Incomplete suppression of activation was mainly attributed to the large size of the vagal nerve (3.0-3.5 mA) which resulted in a large difference of the excitation thresholds of nerve fibers at different distances from the electrode, as well as a relatively short duration of slowly rising pulses. The technique of anodal block required the highest currents. The techniques of slowly rising pulses and anodal block required comparable charge per phase that was larger than for the technique of depolarizing prepulses. Depolarizing prepulses were an optimal choice regarding maximum required current and charge per phase but were very sensitive to small changes of the current amplitude. The other two techniques were more robust regarding small changes of stimulation parameters. The maximum stimulation frequency, using typical values of stimulation parameters, was 105 Hz for depolarizing prepulses, 30 Hz for anodal block and 28 Hz for slowly rising pulses. Only a technique of depolarizing prepulses had a charge per phase within the safe limits. For the other two techniques it would be necessary to optimize the shape of a stimulation pulse in order to reduce the charge per phase.

  20. Bupivacaine Mandibular Nerve Block Affects Intraoperative Blood Pressure and Heart Rate in a Yucatan Miniature Swine Mandibular Condylectomy Model: A Pilot Study

    PubMed Central

    Bova, Jonathan F.; da Cunha, Anderson F.; Stout, Rhett W.; Bhumiratana, Sarindr; Alfi, David M.; Eisig, Sidney B.; Vunjak-Novakovic, Gordana; Lopez, Mandi J.

    2015-01-01

    Purpose/Aim The primary objective was to evaluate the effect of a bupivacaine mandibular nerve block on intraoperative blood pressure (BP) and heart rate (HR) in response to surgical stimulation and the need for systemic analgesics postoperatively. We hypothesized that a mandibular nerve block would decrease the need for systemic analgesics both intraoperatively and postoperatively. Materials and Methods Fourteen adult male Yucatan pigs were purchased. Pigs were chemically restrained with ketamine, midazolam, and dexmedetomidine and anesthesia was maintained with isoflurane inhalant anesthesia. Pigs were randomized to receive a mandibular block with either bupivacaine (bupivacaine group) or saline (control group). A nerve stimulator was used for administration of the block with observation of masseter muscle twitch to indicate the injection site. Invasive BP and HR were measured with the aid of an arterial catheter in eight pigs. A rescue analgesic protocol consisting of fentanyl and lidocaine was administered if HR or BP values increased 20% from baseline. Postoperative pain was quantified with a customized ethogram. HR and BP were evaluated at base line, pre-rescue, 10 and 20 min post-rescue. Results Pre-rescue mean BP was significantly increased (p = .001) for the bupivacaine group. Mean intraoperative HR was significantly lower (p = .044) in the bupivacaine versus saline group. All other parameters were not significant. Conclusion Addition of a mandibular nerve block to the anesthetic regimen in the miniature pig condylectomy model may improve variations in intraoperative BP and HR. This study establishes the foundation for future studies with larger animal numbers to confirm these preliminary findings. PMID:25394295

  1. What blocks health visitors from taking on a leadership role?

    PubMed

    Hyett, Erika

    2003-07-01

    Current government documents in the United Kingdom call for all nurses to take on a greater leadership role. This paper critically considers some of the management factors that block one group of specialist nurses (health visitors) from fulfilling their leadership role. Health visitors have a key role to play in meeting the public health targets of local primary care trusts, known as local health improvement plans. But to take on a greater public health role, health visitors need to move away from working independently within separate general practitioner surgeries and to work in teams which share the vision and goals of the primary care trusts. The paper explores different styles of management that promote transformational leadership and relate to practice. It is suggested that use of the Servant-Leader model of management should encourage the empowerment of staff, and through empowerment health visitors should be able to instigate change and become more innovative in their practice. Persistent recruitment and retention problems have resulted in little time being available to focus on the effectiveness of services. The future management of health visitors will be to primarily run the service while supporting staff in accessing and influencing those in power.

  2. A Self-Administered Method of Acute Pressure Block of Sciatic Nerves for Short-Term Relief of Dental Pain: A Randomized Study

    PubMed Central

    Wang, Xiaolin; Zhao, Wanghong; Wang, Ye; Hu, Jiao; Chen, Qiu; Yu, Juncai; Wu, Bin; Huang, Rong; Gao, Jie; He, Jiman

    2014-01-01

    Objectives While stimulation of the peripheral nerves increases the pain threshold, chronic pressure stimulation of the sciatic nerve is associated with sciatica. We recently found that acute pressure block of the sciatic nerve inhibits pain. Therefore, we propose that, the pain pathology-causing pressure is chronic, not acute. Here, we report a novel self-administered method: acute pressure block of the sciatic nerves is applied by the patients themselves for short-term relief of pain from dental diseases. Design This was a randomized, single-blind study. Setting Hospital patients. Patients Patients aged 16–60 years with acute pulpitis, acute apical periodontitis, or pericoronitis of the third molar of the mandible experiencing pain ≥3 on the 11-point numerical pain rating scale. Interventions Three-minute pressure to sciatic nerves was applied by using the hands (hand pressure method) or by having the patients squat to force the thigh and shin as tightly as possible on the sandwiched sciatic nerve bundles (self-administered method). Outcomes The primary efficacy variable was the mean difference in pain scores from the baseline. Results One hundred seventy-two dental patients were randomized. The self-administered method produced significant relief from pain associated with dental diseases (P ≤ 0.001). The analgesic effect of the self-administered method was similar to that of the hand pressure method. Conclusions The self-administered method is easy to learn and can be applied at any time for pain relief. We believe that patients will benefit from this method. PMID:24400593

  3. Superior Hypogastric Nerve Block to Reduce Pain After Uterine Artery Embolization: Advanced Technique and Comparison to Epidural Anesthesia

    SciTech Connect

    Binkert, Christoph A.; Hirzel, Florian C.; Gutzeit, Andreas; Zollikofer, Christoph L.; Hess, Thomas

    2015-10-15

    PurposeTo evaluate a modified superior hypogastric nerve block (SHNB) to reduce pain after uterine artery embolization (UAE) compared to epidural anesthesia.Materials and methodsIn this retrospective study, the amount of opiate drugs needed after UAE was compared between SHNB and epidural anesthesia. Eighty one consecutive women (mean age: 43.67 years) were in the SHNB group and 27 consecutive women (mean age: 43.48 years) treated earlier at the same institution in the epidural anesthesia group. UAE was performed from a unilateral femoral artery approach using a 4F catheter. 500–700 or 700–900 μm trisacryl gelatine microspheres were used as embolic agents. The SHNB was performed by advancing a 21G from the abdominal wall below the umbilicus to the anterior portion of the 5th vertebral body. For optimal guidance a cranio-caudal tilt of 5°–15° was used. On a lateral view the correct contrast distribution in front of the vertebral body is confirmed. Then 20 ml local anesthesia (ropivacain 0.75 %) is injected. In case of an asymmetric right–left distribution the needle was repositioned.ResultsAll SHNB were successful without severe complications. The mean time for the SHNB was 4 min 38 s (2 min 38 s–9 min 27 s). The needle was repositioned in average 0.87 times. The opiate dose for the SHNB group was 19.33 ± 22.17 mg which was significantly lower. The average time to receive an opiate drug after SHNB was 4 h 41 min.ConclusionThe SHNB is a safe and minimally time-consuming way to reduce pain after UAE especially within the first 4 h.

  4. Anesthetic efficacy of a repeated intraosseous injection given 30 min following an inferior alveolar nerve block/intraosseous injection.

    PubMed Central

    Reitz, J.; Reader, A.; Nist, R.; Beck, M.; Meyers, W. J.

    1998-01-01

    To determine whether a repeated intraosseous (IO) injection would increase or prolong pulpal anesthesia, we measured the degree of anesthesia obtained by a repeated IO injection given 30 min following a combination inferior alveolar nerve block/intraosseous injection (IAN/IO) in mandibular second premolars and in first and second molars. Using a repeated-measures design, we randomly assigned 38 subjects to receive two combinations of injections at two separate appointments. The combinations were an IAN/IO injection followed approximately 30 min later by another IO injection of 0.9 ml of 2% lidocaine with 1:100,000 epinephrine and a combination IAN/IO injection followed approximately 30 min later by a mock IO injection. The second premolar, first molar, and second molar were blindly tested with an Analytic Technology pulp tester at 2-min cycles for 120 min postinjection. Anesthesia was considered successful when two consecutive readings of 80 were obtained. One hundred percent of the subjects had lip numbness with IAN/IO and with IAN/IO plus repeated IO techniques. Rates of anesthetic success for the IAN/IO and for the IAN/IO plus repeated IO injection, respectively, were 100% and 97% for the second premolar, 95% and 95% for the first molar, and 87% and 87% for the second molar. The repeated IO injection increased pulpal anesthesia for approximately 14 min in the second premolar and for 6 min in the first molar, but no statistically significant differences (P > 0.05) were shown. In conclusion, the repeated IO injection of 0.9 ml of 2% lidocaine with 1:100,000 epinephrine given 30 min following a combination IAN/IO injection did not significantly increase pulpal anesthesia in mandibular second premolars or in first and second molars. PMID:10483386

  5. Anaesthetic efficacy of bupivacaine 2-hydroxypropyl-β-cyclodextrin for dental anaesthesia after inferior alveolar nerve block in rats.

    PubMed

    Serpe, L; Franz-Montan, M; Santos, C P dos; Silva, C B da; Nolasco, F P; Caldas, C S; Volpato, M C; Paula, E de; Groppo, F C

    2014-05-01

    Bupivacaine is a long-acting local anaesthetic that is widely used in medicine and dentistry. The duration and intensity of its sensory blockade in animal models is increased by its inclusion in complexes with cyclodextrins. The aim of the present study was to evaluate the anaesthetic efficacy of bupivacaine 2-hydroxypropyl-β-cyclodextrin (HPβCD) inclusion complex for dental anaesthesia after inferior alveolar nerve block in rats. Thirty rats were each given an injection close to the mandibular foramen of 0.2ml of one of the following formulations: 0.5% bupivacaine alone; 0.5% bupivacaine with 1:200,000 epinephrine; and 0.5% bupivacaine-HPβCD inclusion complex (bupivacaine-HPβCD). The other sides were used as controls, with either 0.9% saline or anaesthetic-free HPβCD solution being injected. The onset, success, and duration of pulpal anaesthesia were assessed by electrical stimulation ("pulp tester") on inferior molars. Results were analysed using ANOVA (Tukey), log rank, and chi square tests (α=5%). There were no differences among the formulations in onset of anaesthesia (p=0.59) or between the bupivacaine plus epinephrine and bupivacaine plus HPβCD in duration of anaesthesia, but bupivacaine plus epinephrine gave significantly higher values than bupivacaine alone (p=0.007). Bupivacaine plus epinephrine was a better anaesthetic than bupivacaine alone (p=0.02), while Bupi-HPβCD gave intermediate results, and therefore did not differ significantly from the other 2 groups (p=0.18 with bupivacaine alone; and p=0.44 with bupivacaine plus epinephrine). The bupivacaine-HPβCD complex showed similar anaesthetic properties to those of bupivacaine with epinephrine.

  6. Role of HDACs in optic nerve damage-induced nuclear atrophy of retinal ganglion cells.

    PubMed

    Schmitt, Heather M; Schlamp, Cassandra L; Nickells, Robert W

    2016-06-20

    Optic neuropathies are characterized by retinal ganglion cell (RGC) death, resulting in the loss of vision. In glaucoma, the most common optic neuropathy, RGC death is initiated by axonal damage, and can be modeled by inducing acute axonal trauma through procedures such as optic nerve crush (ONC) or optic nerve axotomy. One of the early events of RGC death is nuclear atrophy, and is comprised of RGC-specific gene silencing, histone deacetylation, heterochromatin formation, and nuclear shrinkage. These early events appear to be principally regulated by epigenetic mechanisms involving histone deacetylation. Class I histone deacetylases HDACs 1, 2, and 3 are known to play important roles in the process of early nuclear atrophy in RGCs, and studies using both inhibitors and genetic ablation of Hdacs also reveal a critical role in the cell death process. Select inhibitors, such as those being developed for cancer therapy, may also provide a viable secondary treatment option for optic neuropathies.

  7. Role of transcutaneous electric nerve stimulation in the management of trigeminal neuralgia

    PubMed Central

    Singla, Sanju; Prabhakar, Vikram; Singla, Rajan Kumar

    2011-01-01

    Background: Trigeminal neuralgia typically involves nerves supplying teeth, jaws and face of older females. Though the etiology is usually obscure, different treatment modalities have been tried for it viz. medicinal treatment, injection alcohol, peripheral neurectomy, rhizotomy, and microvascular decompression etc. Transcutaneous electric nerve stimulation (TENS) is an emerging and promising option for management of such patients. Aims and Design: The present study was designed with an aim to study the efficacy of TENS in management of trigeminal neuralgia. Materials and Methods: The study was conducted on 30 patients of trigeminal neuralgia confirmed by diagnostic nerve block. They were given bursts of TENS for 20-40 days over the path of the affected nerve and subsequently evaluated at 1 month and 3 month intervals by visual analogue scale (VAS), verbal pain scale (VPS), a functional outcome scales for main daily activities like sleep, chewing, talking, or washing face. Results: The results showed that, on VAS, the score decreased from 8.9 (Pre TENS) to 3.1 at 1 month and 1.3 at 3 months, and on VPS, the score decreased from 3.5 (Pre TENS) to 1.2 at 1 month and 0.3 at 3 months. Similarly, a considerable decrease in scores was seen on functional outcome scale for different activities. No side effects like irritation or redness of skin were seen in any of the patients. Conclusions: Thus, TENS was found to be a safe, easily acceptable, and non-invasive outdoor patient department procedure for management of trigeminal neuralgia. PMID:21897677

  8. Role of sensory nerves in the rapid cutaneous vasodilator response to local heating in young and older endurance-trained and untrained men.

    PubMed

    Tew, Garry A; Klonizakis, Markos; Moss, James; Ruddock, Alan D; Saxton, John M; Hodges, Gary J

    2011-02-01

    The ability to increase skin blood flow (SkBF) rapidly in response to local heating is diminished with advanced age; however, the mechanisms are unclear. The primary aim of this study was to investigate the role of sensory nerves in this age-related change. A secondary aim was to investigate the effect of aerobic fitness on sensory nerve-mediated vasodilatation in young and aged skin. We measured SkBF (using laser Doppler flowmetry) in young and older endurance-trained and untrained men (n= 7 in each group) at baseline and during 35 min of local skin heating to 42°C at two sites on the ventral forearm. One site was pretreated with topical anaesthetic cream to block local sensory nerve function. Cutaneous vascular conductance (CVC) was calculated as SkBF divided by mean arterial pressure and normalized to maximal values (CVC(max)) achieved during local heating to 44°C. At the untreated site, the rapid vasodilatation during the first ~5 min of local heating (initial peak) was lower in the older untrained group (68 ± 3%CVC(max)) compared with all other groups (young trained, 76 ± 4%CVC(max); young untrained, 75 ± 5%CVC(max); and older trained, 81 ± 3%CVC(max); P < 0.05). Sensory nerve blockade abolished these differences among the groups (P > 0.05). The contribution of sensory nerve-mediated vasodilatation was lower in the older untrained group compared with all other groups (P< 0.05). Our results suggest that the age-related decline in the rapid vasodilator response to local heating in human skin is explained by diminished sensory nerve-mediated vasodilatation. These findings also indicate that this age-related change can be prevented through participation in regular aerobic exercise.

  9. Inferior alveolar nerve block by injection into the pterygomandibular space anterior to the mandibular foramen: radiographic study of local anesthetic spread in the pterygomandibular space.

    PubMed Central

    Okamoto, Y.; Takasugi, Y.; Moriya, K.; Furuya, H.

    2000-01-01

    We studied the spread of local anesthetic solution in the inferior alveolar nerve block by the injection of local anesthetic solution into the pterygomandibular space anterior to the mandibular foramen (anterior technique). Seventeen volunteers were injected with 1.8 mL of a mixture containing lidocaine and contrast medium utilizing the anterior technique. The course of spread was traced by fluoroscopy in the sagittal plane, and the distribution area was evaluated by lateral cephalograms and horizontal computed tomography. The results indicate that the contrast medium mixture spreads rapidly in the pterygomandibular space to the inferior alveolar nerve in the subjects who exhibited inferior alveolar nerve block effect. We concluded that the anesthetic effect due to the anterior technique was produced by the rapid distribution of anesthetic solution in the pterygomandibular space toward the mandibular foramen, and individual differences in the time of onset of analgesia may be due to differences in the histologic perineural tissues. Images Figure 1 Figure 2 Figure 3 PMID:11432178

  10. Effects of pyrethroid molecules on rat nerves in vitro: potential to reverse temperature-sensitive conduction block of demyelinated peripheral axons

    PubMed Central

    Lees, George

    1998-01-01

    Prolongation of action potentials by cooling or pharmacological treatment can restore conduction in demyelinated axons. We have assessed the ability of pyrethroids (in vitro) to modify action potential kinetics and to reverse conduction block in lesioned peripheral nerve. Fast Na+ currents were isolated in mammalian neuroblastoma (NIE115). Pyrethroids (4 μM) concurrently slowed inactivation and produced a spectrum of pronounced tail currents: s-bioallethrin (duration 12.2±7 ms), permethrin (24.2±3 ms) and deltamethrin (2230±100 ms). Deltamethrin (5 μM) effected a slowly developing depression of compound action potential (CAP) amplitude in peroneal nerve trunks (P<0.05). Permethrin produced no net effect on CAP amplitude, area or repolarization time. s-Bioallethrin (5 μM) enhanced CAP area, time for 90% repolarization and induced regenerative activity in a subpopulation of axons. Tibial nerve trunks were demyelinated by lysolecithin (2 μl) injection: 6–14 days later, slowly-conducting axons in the CAP (and peri-axonal microelectrode recordings) were selectively blocked by warming to 37°C. At 37°C, s-bioallethrin (45 min, 5 μM) produced much greater after-potentials in lesioned nerves than in uninjected controls: area (P<0.05) and relative amplitude ratios (P<0.0001) were significantly altered. In 3 of 4 cells (single-unit recording), s-bioallethrin restored conduction through axons exhibiting temperature-dependent block by raising blocking temperature (by 1.5 to >3°C) and reducing refractory period. s-Bioallethrin induced temperature-dependent regenerative activity only in a sub-population of axons even after prolonged superfusion (>1 h). It was concluded that pyrethroids differentially alter Na+ current kinetics and action potential kinetics. The effects of s-bioallethrin are consistent with reversal of conduction block by demyelinated axons but regenerative/ectopic firing even in normal cells is likely to underpin its acknowledged

  11. A role for the SHP-2 tyrosine phosphatase in nerve growth-induced PC12 cell differentiation.

    PubMed Central

    Wright, J H; Drueckes, P; Bartoe, J; Zhao, Z; Shen, S H; Krebs, E G

    1997-01-01

    SHP-1 and SHP-2 are intracellular protein tyrosine phosphatases containing two adjacent src homology 2 domains that target these phosphatases to cell surface receptor signaling complexes and play a role in receptor signal transduction. In this report the PC12 cell system was used to investigate the potential roles of SHP-1 and SHP-2 in the induction of neuronal differentiation by nerve growth factor (NGF). By using neurite outgrowth as a marker for differentiation, the effects of transfected constructs of SHP-1 and SHP-2 were assessed. Overexpression of a catalytically inactive SHP-2, but not a catalytically inactive SHP-1, blocked NGF-stimulated neurite outgrowth. The mitogen-activated protein kinase (MAPK) signaling cascade is important for the morphological differentiation in PC12 cells, and both SHP-1 and SHP-2 have been implicated to act upstream of MAPK in other receptor signaling systems. A positive role for SHP-2 but not SHP-1 in the activation of MAPK by NGF was demonstrated by introduction of the SHP-2 phosphatase mutants along with hemagglutinin-tagged MAPK. Coexpression studies with the SHP-2 mutant along with mutant forms of MAPK kinase suggested that SHP-2 functions upstream of MAPK kinase and MAPK in NGF-induced neurite outgrowth. Images PMID:9285826

  12. The midline protein regulates axon guidance by blocking the reiteration of neuroblast rows within the Drosophila ventral nerve cord.

    PubMed

    Manavalan, Mary Ann; Gaziova, Ivana; Bhat, Krishna Moorthi

    2013-01-01

    Guiding axon growth cones towards their targets is a fundamental process that occurs in a developing nervous system. Several major signaling systems are involved in axon-guidance, and disruption of these systems causes axon-guidance defects. However, the specific role of the environment in which axons navigate in regulating axon-guidance has not been examined in detail. In Drosophila, the ventral nerve cord is divided into segments, and half-segments and the precursor neuroblasts are formed in rows and columns in individual half-segments. The row-wise expression of segment-polarity genes within the neuroectoderm provides the initial row-wise identity to neuroblasts. Here, we show that in embryos mutant for the gene midline, which encodes a T-box DNA binding protein, row-2 neuroblasts and their neuroectoderm adopt a row-5 identity. This reiteration of row-5 ultimately creates a non-permissive zone or a barrier, which prevents the extension of interneuronal longitudinal tracts along their normal anterior-posterior path. While we do not know the nature of the barrier, the axon tracts either stall when they reach this region or project across the midline or towards the periphery along this zone. Previously, we had shown that midline ensures ancestry-dependent fate specification in a neuronal lineage. These results provide the molecular basis for the axon guidance defects in midline mutants and the significance of proper specification of the environment to axon-guidance. These results also reveal the importance of segmental polarity in guiding axons from one segment to the next, and a link between establishment of broad segmental identity and axon guidance.

  13. Role of macrophages in Wallerian degeneration and axonal regeneration after peripheral nerve injury.

    PubMed

    Chen, Peiwen; Piao, Xianhua; Bonaldo, Paolo

    2015-11-01

    The peripheral nervous system (PNS) has remarkable regenerative abilities after injury. Successful PNS regeneration relies on both injured axons and non-neuronal cells, including Schwann cells and immune cells. Macrophages are the most notable immune cells that play key roles in PNS injury and repair. Upon peripheral nerve injury, a large number of macrophages are accumulated at the injury sites, where they not only contribute to Wallerian degeneration, but also are educated by the local microenvironment and polarized to an anti-inflammatory phenotype (M2), thus contributing to axonal regeneration. Significant progress has been made in understanding how macrophages are educated and polarized in the injured microenvironment as well as how they contribute to axonal regeneration. Following the discussion on the main properties of macrophages and their phenotypes, in this review, we will summarize the current knowledge regarding the mechanisms of macrophage infiltration after PNS injury. Moreover, we will discuss the recent findings elucidating how macrophages are polarized to M2 phenotype in the injured PNS microenvironment, as well as the role and underlying mechanisms of macrophages in peripheral nerve injury, Wallerian degeneration and regeneration. Furthermore, we will highlight the potential application by targeting macrophages in treating peripheral nerve injury and peripheral neuropathies.

  14. Role of Cell Block in Guided FNAC of Abdominal Masses

    PubMed Central

    Manoli, Nandini; Shivajirao, Prathima; Manjunath; Jothady, Sunila

    2016-01-01

    Introduction Fine Needle Aspiration (FNA) of space occupying lesions in superficial or deep anatomic sites is an increasingly common procedure, providing rapid and safe diagnosis. However, sometimes FNA does not yield sufficient information for a precise diagnosis and the risk of false negatives and indeterminate diagnosis is always present. Therefore, we attempted to obtain additional information via the preparation of Cell Block (CB) from the residual material of aspirates and thus enhance the diagnostic accuracy. Aim This study was carried out to evaluate the role of CB as a useful adjunct to smears for establishing a more definitive cytopathologic diagnosis and for its utility in special staining and Immuno-histochemistry (IHC). Materials and Methods A total of 66 cases of image-guided FNA of abdominal masses were studied. In addition to the routine smears, CBs were prepared from the residual tissues for all possible cases and its diagnostic efficacy was analysed. Further, the use of CBs for special staining and IHC was also established. Results This study included a total of 66 patients with abdominal masses who were referred for guided FNA cytology. Out of these cases, adequate material was obtained on FNAC in 64 cases (96.96%) and on CB in 45 cases (68.18%) and the diagnosis was provided. There was a good agreement between the FNA smear diagnosis and CB diagnosis. The histopathology of CB sections further helped in precise final cytopathological diagnosis. Two FNA smears were unsatisfactory for evaluation and hence the diagnosis was done on CB sections alone. With FNA cytology and CB in combination, a cytopathological diagnosis was given for all the 66 cases. The sensitivity of FNA in comparison to the histopathology of CB was 91.6% and specificity was 88.8%. The diagnostic accuracy was 62% and the discordance was 6%. Conclusions CB in addition to the routine FNA is a simple, reliable and cost-effective technique that further contributes to the final

  15. Intravenous analgesia with opioids versus femoral nerve block with 0.2% ropivacaine as preemptive analgesic for fracture femur: A randomized comparative study

    PubMed Central

    Singh, Arvinder Pal; Kohli, Vaneet; Bajwa, Sukhminder Jit Singh

    2016-01-01

    Background and Objective: Femoral fractures are extremely painful and pain invariably worsens on any movement. Anesthesia for fracture femur surgery is usually provided by spinal block. This study was undertaken to compare the analgesic effects of femoral nerve block (FNB) using nerve stimulator with 0.2% ropivacaine (15 ml) and intravenous (I.V.) fentanyl before patient positioning for fracture femur surgery under spinal anesthesia. Materials and Methods: A prospective, randomized, double-blind, comparative study was conducted on 60 American Society of Anesthesiologists I and II patients (18–60 years) scheduled for femur surgery under combined spinal epidural anesthesia. Patients in Group I (n = 30), were administered FNB using nerve stimulator with 0.2% ropivacaine (15 ml) and in Group II patients (n = 30), I.V. fentanyl 0.5 μg/kg was given as preemptive analgesia. Parameters observed included time to spinal anesthesia, intra-operative and postoperative visual analog scale (VAS) for any pain and postoperative epidural top-ups dosages. Results: Demographic profile was comparable in both the groups. VAS at 2 min in Group I was 5.63 and in Group II it was 8.00. Satisfaction score was better in Group I as compared to Group II patients. Time to administer subarachnoid block was 17.80 min in patients of Group I as compared to 25.03 min in Group II patients. Postoperatively, VAS scores were lower in Group I than Group II patients. The frequency of epidural top-ups was higher in Group II than in Group I patients. Conclusions: FNB is comparatively better in comparison to I.V. fentanyl when used as preemptive and postoperative analgesic in patients being operated for fracture femur. PMID:27212771

  16. Molecular mechanisms of peripheral nerve regeneration: emerging roles of microRNAs

    PubMed Central

    Wu, Di; Murashov, Alexander K.

    2013-01-01

    MicroRNAs are small non-coding RNAs that suppress gene expression through target mRNA degradation or translation repression. Recent studies suggest that miRNA plays an important role in multiple physiological and pathological processes in the nervous system. In this review article, we described what is currently known about the mechanisms in peripheral nerve regeneration on cellular and molecular levels. Recently, changes in microRNA expression profiles have been detected in different injury models, and emerging evidence strongly indicates that these changes promote neurons to survive by shifting their physiology from maintaining structure and supporting synaptic transmission towards a regenerative phenotype. We reviewed the putative mechanisms involved in miRNA mediated post-transcriptional regulation and pointed out several areas where future research is necessary to advance our understanding of how targeting miRNA machinery can be used as a therapeutic approach for treating nerve injuries. PMID:23554595

  17. Comparison of effectiveness of 4% articaine associated with 1: 100,000 or 1: 200,000 epinephrine in inferior alveolar nerve block.

    PubMed Central

    Tófoli, Giovana Radomille; Ramacciato, Juliana Cama; de Oliveira, Patrícia Cristine; Volpato, Maria Cristina; Groppo, Francisco Carlos; Ranali, José

    2003-01-01

    This comparative study using 20 healthy volunteers evaluated the anesthetic efficacy of 4% articaine in association with 2 different concentrations of epinephrine, 1:200,000 (G1) and 1:100,000 (G2). The first premolars were tested with a pulp tester to verify the anesthesia induced by the inferior alveolar nerve block. The following parameters were measured: period of latency (PL; interval between the end of anesthetic injection and absence of response to the maximum output--80 reading--of the pulp tester); complete pulpal anesthesia (CPA; period in which the subject had no response to maximal output of the pulp tester 80 reading); partial anesthesia (PA; interval between the first reading below 80 and the return to basal levels); and the anesthesia of the soft tissues (AST; period of time from onset of anesthesia until the return to normal sensation of the lip). The Wilcoxon test (alpha = 0.05) was used to analyze the data. No significant difference was found regarding PL (P = .47), CPA (P = .88), PA (P = .46), and AST (P = .85). The results indicated that both solutions presented the same clinical effectiveness in blocking the inferior alveolar nerve. PMID:14959904

  18. The Role of Current Techniques and Concepts in Peripheral Nerve Repair.

    PubMed

    Houschyar, K S; Momeni, A; Pyles, M N; Cha, J Y; Maan, Z N; Duscher, D; Jew, O S; Siemers, F; van Schoonhoven, J

    2016-01-01

    Patients with peripheral nerve injuries, especially severe injury, often face poor nerve regeneration and incomplete functional recovery, even after surgical nerve repair. This review summarizes treatment options of peripheral nerve injuries with current techniques and concepts and reviews developments in research and clinical application of these therapies. PMID:26904282

  19. The Role of Current Techniques and Concepts in Peripheral Nerve Repair

    PubMed Central

    Houschyar, K. S.; Momeni, A.; Pyles, M. N.; Cha, J. Y.; Maan, Z. N.; Duscher, D.; Jew, O. S.; Siemers, F.; van Schoonhoven, J.

    2016-01-01

    Patients with peripheral nerve injuries, especially severe injury, often face poor nerve regeneration and incomplete functional recovery, even after surgical nerve repair. This review summarizes treatment options of peripheral nerve injuries with current techniques and concepts and reviews developments in research and clinical application of these therapies. PMID:26904282

  20. Improved perioperative analgesia with ultrasound-guided ilioinguinal/iliohypogastric nerve or transversus abdominis plane block for open inguinal surgery: a systematic review and meta-analysis of randomized controlled trials

    PubMed Central

    Wang, Yuexiang; Wu, Tao; Terry, Marisa J.; Eldrige, Jason S.; Tong, Qiang; Erwin, Patricia J.; Wang, Zhen; Qu, Wenchun

    2016-01-01

    [Purpose] Ultrasound-guided ilioinguinal/iliohypogastric (II/IH) nerve and transversus abdominis plane (TAP) blocks have been increasingly utilized in patients for perioperative analgesia. We conducted this meta-analysis to evaluate the clinical efficacy of ultrasound-guided II/IH nerve or TAP blocks for perioperative analgesia in patients undergoing open inguinal surgery. [Subjects and Methods] A systematic search was conducted of 7 databases from the inception to March 5, 2015. Randomized controlled trials (RCTs) comparing the clinical efficacy of ultrasound-guided vs. landmark-based techniques to perform II/IH nerve and TAP blocks in patients with open inguinal surgery were included. We constructed random effects models to pool the standardized mean difference (SMD) for continuous outcomes and the odds ratio (OR) for dichotomized outcomes. [Results] Ultrasound-guided II/IH nerve or TAP blocks were associated with a reduced use of intraoperative additional analgesia and a significant reduction of pain scores during day-stay. The use of rescue drugs was also significantly lower in the ultrasound-guided group. [Conclusion] The use of ultrasound-guidance to perform an II/IH nerve or a TAP block was associated with improved perioperative analgesia in patients following open inguinal surgery compared to landmark-based methods. PMID:27134411

  1. [Who is responsible for the postoperative nerve injury? Anesthesia? Orthopedics? Trauma?].

    PubMed

    Kelsaka, Ebru; Güldoğuş, Fuat; Erdoğan, Murat; Zengin, Eyüp Cağatay

    2014-01-01

    In the pathogenesis of peripheral nerve injury, mechanical as well as vascular pressure, and chemical reasons play a role. In the applications of peripheral nerve block, there can be mechanical injury due to the type of needle and intrafascicular injections. In humerus fractures, nerve injury can be seen due to the surgical retractions and close proximity of the nerves with the bone. In addition, trauma may be the reason for posttraumatic nerve injury. In this presentation, we discussed the causes of postoperative nerve damage, which is seen after the operation of the distal humerus fracture.

  2. Human cutaneous reactive hyperaemia: role of BKCa channels and sensory nerves.

    PubMed

    Lorenzo, Santiago; Minson, Christopher T

    2007-11-15

    Reactive hyperaemia is the increase in blood flow following arterial occlusion. The exact mechanisms mediating this response in skin are not fully understood. The purpose of this study was to investigate the individual and combined contributions of (1) sensory nerves and large-conductance calcium activated potassium (BKCa) channels, and (2) nitric oxide (NO) and prostanoids to cutaneous reactive hyperaemia. Laser-Doppler flowmetry was used to measure skin blood flow in a total of 18 subjects. Peak blood flow (BF) was defined as the highest blood flow value after release of the pressure cuff. Total hyperaemic response was calculated by taking the area under the curve (AUC) of the hyperaemic response minus baseline. Infusates were perfused through forearm skin using microdialysis in four sites. In the sensory nerve/BKCa protocol: (1) EMLA cream (EMLA, applied topically to skin surface), (2) tetraethylammonium (TEA), (3) EMLA + TEA (Combo), and (4) Ringer solution (Control). In the prostanoid/NO protocol: (1) ketorolac (Keto), (2) NG-nitro-l-arginine methyl ester (L-NAME), (3) Keto + l-NAME (Combo), and (4) Ringer solution (Control). CVC was calculated as flux/mean arterial pressure and normalized to maximal flow. Hyperaemic responses in Control (1389 +/- 794%CVC max s) were significantly greater compared to TEA, EMLA and Combo sites (TEA, 630 +/- 512, P = 0.003; EMLA, 421 +/- 216, P < 0.001; Combo, 201 +/- 200, P < 0.001%CVC max s). Furthermore, AUC in Combo (Keto + l-NAME) site was significantly greater than Control (4109 +/- 2777 versus 1295 +/- 368%CVC max s). These data suggest (1) sensory nerves and BKCa channels play major roles in the EDHF component of reactive hyperaemia and appear to work partly independent of each other, and (2) the COX pathway does not appear to have a vasodilatory role in cutaneous reactive hyperaemia.

  3. Ultrasound-guided femoro-sciatic nerve block for post-operative analgesia after below knee orthopaedic surgeries under subarachnoid block: Comparison between clonidine and dexmedetomidine as adjuvants to levobupivacaine

    PubMed Central

    Chaudhary, Sudarshan Kumar; Verma, Ravinder Kumar; Rana, Shelly; Singh, Jai; Gupta, Bhanu; Singh, Yuvraj

    2016-01-01

    Background and Aims: The advent of ultrasonographic-guided techniques has led to increased interest in femoro-sciatic nerve block (FSNB) for lower limb surgeries. α2-agonists have been used recently as adjuvants to local anaesthetics in nerve blocks. We aimed to compare equal doses of clonidine or dexmedetomidine as an adjuvant to levobupivacaine in FSNB for post-operative analgesia. Methods: Ninety patients scheduled to undergo below knee orthopaedic surgeries under subarachnoid block were divided into three groups: Group LL (n = 30) patients received 38 mL of 0.125% levobupivacaine with 2 mL normal saline, Group LD (n = 30) patients received 38 mL of 0.125% levobupivacaine with 0.5 μg/kg dexmedetomidine and Group LC (n = 30) received 38 mL of 0.125% levobupivacaine with 0.5 μg/kg clonidine in saline to make total drug volume of 40 mL. The primary and secondary outcome variables were duration of analgesia and rescue analgesic requirement, verbal rating score respectively. Continuous variables were analysed with analysis of variance or the Kruskal–Wallis test on the basis of data distribution. Categorical variables were analysed with the contingency table analysis and the Fisher's exact test. Results: Duration of analgesia was prolonged with dexmedetomidine (10.17 ± 2.40 h) and clonidine (7.31 ± 1.76 h) as compared to control (4.16 ± 1.04 h, P = 0.00). Significantly lower pain scores were observed in dexmedetomidine group as compared to clonidine up to 8 h post-operatively. Conclusion: Equal doses of clonidine or dexmedetomidine added to levobupivacaine prolonged the duration of analgesia, decreased requirement of rescue analgesia. Dexmedetomidine delays the requirement of rescue analgesics with better pain scores as compared to clonidine. PMID:27512164

  4. Block Building: Its Role in Children's Learning as Seen by One Elementary School Teacher.

    ERIC Educational Resources Information Center

    Werbizky, Lydia

    1991-01-01

    The role of block building in children's learning was studied by a student teacher who observed a teacher's block building curriculum in a combined first and second grade class. The purpose was to clarify the linkage between thinking and doing, spoken intention and actual consequences, and planning and spontaneity in the curriculum. The cycle of…

  5. Leptin differentially increases sympathetic nerve activity and its baroreflex regulation in female rats: role of oestrogen.

    PubMed

    Shi, Zhigang; Brooks, Virginia L

    2015-04-01

    Obesity and hypertension are commonly associated, and activation of the sympathetic nervous system is considered to be a major contributor, at least in part due to the central actions of leptin. However, while leptin increases sympathetic nerve activity (SNA) in males, whether leptin is equally effective in females is unknown. Here, we show that intracerebroventricular (i.c.v.) leptin increases lumbar (LSNA) and renal (RSNA) SNA and baroreflex control of LSNA and RSNA in α-chloralose anaesthetized female rats, but only during pro-oestrus. In contrast, i.c.v. leptin increased basal and baroreflex control of splanchnic SNA (SSNA) and heart rate (HR) in rats in both the pro-oestrus and dioestrus states. The effects of leptin on basal LSNA, RSNA, SSNA and HR were similar in males and pro-oestrus females; however, i.c.v. leptin increased mean arterial pressure (MAP) only in males. Leptin did not alter LSNA or HR in ovariectomized rats, but its effects were normalized with 4 days of oestrogen treatment. Bilateral nanoinjection of SHU9119 into the paraventricular nucleus of the hypothalamus (PVN), to block α-melanocyte-stimulating hormone (α-MSH) type 3 and 4 receptors, decreased LSNA in leptin-treated pro-oestrus but not dioestrus rats. Unlike leptin, i.c.v. insulin infusion increased basal and baroreflex control of LSNA and HR similarly in pro-oestrus and dioestrus rats; these responses did not differ from those in male rats. We conclude that, in female rats, leptin's stimulatory effects on SNA are differentially enhanced by oestrogen, at least in part via an increase in α-MSH activity in the PVN. These data further suggest that the actions of leptin and insulin to increase the activity of various sympathetic nerves occur via different neuronal pathways or cellular mechanisms. These results may explain the poor correlation in females of SNA with adiposity, or of MAP with leptin. PMID:25398524

  6. Plasticity in rat uterine sympathetic nerves: the role of TrkA and p75 nerve growth factor receptors

    PubMed Central

    Richeri, Analía; Bianchimano, Paola; Mármol, Nelson M; Viettro, Lorena; Cowen, Timothy; Brauer, M Mónica

    2005-01-01

    Uterine sympathetic innervation undergoes profound remodelling in response to physiological and experimental changes in the circulating levels of sex hormones. It is not known, however, whether this plasticity results from changes in the innervating neurons, the neuritogenic properties of the target tissue or both. Using densitometric immunohistochemistry, we analysed the effects of prepubertal chronic oestrogen treatment (three subcutaneous injections of 20 µg of β-oestradiol 17-cypionate on days 25, 27 and 29 after birth), natural peripubertal transition and late pregnancy (19–20 days post coitum) on the levels of TrkA and p75 nerve growth factor receptors in uterine-projecting sympathetic neurons of the thoraco-lumbar paravertebral sympathetic chain (T7–L2) identified using the retrograde tracer Fluorogold. For comparative purposes, levels of TrkA and p75 were assessed in the superior cervical ganglion (SCG) following prepubertal chronic oestrogen treatment. These studies showed that the vast majority of uterine-projecting neurons expressed both TrkA and p75. Both prepubertal chronic oestrogen treatment and the peripubertal transition increased the ratio p75 to TrkA in uterine-projecting neurons, whereas pregnancy elicited the opposite effect. Prepubertal chronic oestrogen treatment had no effects on levels of TrkA or p75 in sympathetic neurons of the SCG. Taken together, our data suggest that neurotrophin receptor-mediated events may contribute to regulate sex hormone-induced plasticity in uterine sympathetic nerves, and are in line with the idea that, in vivo, plasticity in uterine nerves involves changes in both the target and the innervating neurons. PMID:16050899

  7. A Prospective Observational Cohort Study on Orthopaedic and Anaesthetic Registrars Performing Femoral Nerve Block on Patients with an Acute Hip Fracture

    PubMed Central

    Thelaus, Åsa; Pettersson, Tobias; Gordon, Max

    2016-01-01

    We investigated if a femoral nerve block (FNB) for patients with a proximal femoral fracture (PFF) and administered by an orthopaedic registrar (OR) instead of an anaesthesiology registrar (AR) lowers the lead time to block and reduces the total amount of rescue analgesics during the preoperative phase. 205 patients were included in a prospective observational cohort study. The main outcome variable was rescue analgesics as total intravenous morphine prior to surgery. All results were adjusted for confounding using age, sex, cognitive dysfunction, and ASA classification. The OR group (n = 135) was over 2 hours faster in performing the block compared to the AR group (n = 70) but was nonetheless correlated with an increased amount of rescue analgesics during the study, 2.4 mg morphine (95% CI 0.0–4.9) more compared to the AR group. We found no difference between the groups in the risk of adverse events. We conclude that, for patients with an acute PFF and with morphine consumption as end point, how soon from arrival to hospital the patients receive a FNB is of lesser importance than who is administering it. Based on our results we recommend that emergency hospitals should have routines for anaesthesiologists performing FNB on this frail patient group. PMID:27704039

  8. Roles of estrogen and progesterone in modulating renal nerve function in the rat kidney

    PubMed Central

    Graceli, J.B.; Cicilini, M.A.; Bissoli, N.S.; Abreu, G.R.; Moysés, M.R.

    2013-01-01

    The maintenance of extracellular Na+ and Cl- concentrations in mammals depends, at least in part, on renal function. It has been shown that neural and endocrine mechanisms regulate extracellular fluid volume and transport of electrolytes along nephrons. Studies of sex hormones and renal nerves suggested that sex hormones modulate renal function, although this relationship is not well understood in the kidney. To better understand the role of these hormones on the effects that renal nerves have on Na+ and Cl- reabsorption, we studied the effects of renal denervation and oophorectomy in female rats. Oophorectomized (OVX) rats received 17β-estradiol benzoate (OVE, 2.0 mg·kg-1·day-1, sc) and progesterone (OVP, 1.7 mg·kg-1·day-1, sc). We assessed Na+ and Cl- fractional excretion (FENa+ and FECl-, respectively) and renal and plasma catecholamine release concentrations. FENa+, FECl-, water intake, urinary flow, and renal and plasma catecholamine release levels increased in OVX vs control rats. These effects were reversed by 17β-estradiol benzoate but not by progesterone. Renal denervation did not alter FENa+, FECl-, water intake, or urinary flow values vs controls. However, the renal catecholamine release level was decreased in the OVP (236.6±36.1 ng/g) and denervated rat groups (D: 102.1±15.7; ODE: 108.7±23.2; ODP: 101.1±22.1 ng/g). Furthermore, combining OVX + D (OD: 111.9±25.4) decreased renal catecholamine release levels compared to either treatment alone. OVE normalized and OVP reduced renal catecholamine release levels, and the effects on plasma catecholamine release levels were reversed by ODE and ODP replacement in OD. These data suggest that progesterone may influence catecholamine release levels by renal innervation and that there are complex interactions among renal nerves, estrogen, and progesterone in the modulation of renal function. PMID:23828583

  9. Support of Nerve Conduction by Respiring Myelin Sheath: Role of Connexons.

    PubMed

    Ravera, Silvia; Bartolucci, Martina; Adriano, Enrico; Garbati, Patrizia; Ferrando, Sara; Ramoino, Paola; Calzia, Daniela; Morelli, Alessandro; Balestrino, Maurizio; Panfoli, Isabella

    2016-05-01

    Recently, we have demonstrated that myelin conducts an extramitochondrial oxidative phosphorylation, hypothesizing a novel supportive role for myelin in favor of the axon. We have also hypothesized that the ATP produced in myelin could be transferred thought gap junctions. In this work, by biochemical, immunohistochemical, and electrophysiological techniques, the existence of a connection among myelin to the axon was evaluated, to understand how ATP could be transferred from sheath to the axoplasm. Data confirm a functional expression of oxidative phosphorylation in isolated myelin. Moreover, WB and immunohistochemistry on optic nerve slices show that connexins 32 and 43 are present in myelin and colocalize with myelin basic protein. Interestingly, addition of carbenoxolone or oleamide, two gap junction blockers, causes a decrease in oxidative metabolism in purified myelin, but not in mitochondria. Similar effects were observed on conduction speed in hippocampal Schaffer collateral, in the presence of oleamide. Confocal analysis of optic nerve slices showed that lucifer yellow (that only passes through aqueous pores) signal was found in both the sheath layers and the axoplasma. In the presence of oleamide, but not with oleic acid, signal significantly decreased in the sheath and was lost inside the axon. This suggests the existence of a link among myelin and axons. These results, while supporting the idea that ATP aerobically synthesized in myelin sheath could be transferred to the axoplasm through gap junctions, shed new light on the function of the sheath.

  10. Successful treatment of Raynaud’s syndrome in a lupus patient with continuous bilateral popliteal sciatic nerve blocks: a case report

    PubMed Central

    Dao, Thuan; Amaro-Driedger, David; Mehta, Jaideep

    2016-01-01

    Raynaud’s syndrome has been treated medically and invasively, sometimes with regional anesthesia leading up to sympathectomy. We demonstrate that regional anesthesia was in this case a useful technique that can allow some patients to find temporary but significant relief from symptoms of Raynaud’s syndrome exacerbation. We present a 43-year-old woman with Raynaud’s syndrome secondary to lupus who was treated with bilateral popliteal nerve block catheters for ischemic pain and necrosis of her feet; this led to almost immediate resolution of her pain and return of color and function of her feet. While medical management should continue to be a front-line treatment for Raynaud’s syndrome, regional anesthesia can be useful in providing rapid dissipation of symptoms and may thus serve as a viable option for short-term management of this syndrome. PMID:27366104

  11. Role of Polyalanine Domains in -Sheet Formation in Spider Silk Block Copolymers

    SciTech Connect

    Rabotyagova, O.; Cebe, P; Kaplan, D

    2010-01-01

    Genetically engineered spider silk-like block copolymers were studied to determine the influence of polyalanine domain size on secondary structure. The role of polyalanine block distribution on {beta}-sheet formation was explored using FT-IR and WAXS. The number of polyalanine blocks had a direct effect on the formation of crystalline {beta}-sheets, reflected in the change in crystallinity index as the blocks of polyalanines increased. WAXS analysis confirmed the crystalline nature of the sample with the largest number of polyalanine blocks. This approach provides a platform for further exploration of the role of specific amino acid chemistries in regulating the assembly of {beta}-sheet secondary structures, leading to options to regulate material properties through manipulation of this key component in spider silks.

  12. μ-Conotoxins that differentially block sodium channels NaV1.1 through 1.8 identify those responsible for action potentials in sciatic nerve

    PubMed Central

    Wilson, Michael J.; Yoshikami, Doju; Azam, Layla; Gajewiak, Joanna; Olivera, Baldomero M.; Bulaj, Grzegorz; Zhang, Min-Min

    2011-01-01

    Voltage-gated sodium channels (VGSCs) are important for action potentials. There are seven major isoforms of the pore-forming and gate-bearing α-subunit (NaV1) of VGSCs in mammalian neurons, and a given neuron can express more than one isoform. Five of the neuronal isoforms, NaV1.1, 1.2, 1.3, 1.6, and 1.7, are exquisitely sensitive to tetrodotoxin (TTX), and a functional differentiation of these presents a serious challenge. Here, we examined a panel of 11 μ-conopeptides for their ability to block rodent NaV1.1 through 1.8 expressed in Xenopus oocytes. Although none blocked NaV1.8, a TTX-resistant isoform, the resulting “activity matrix” revealed that the panel could readily discriminate between the members of all pair-wise combinations of the tested isoforms. To examine the identities of endogenous VGSCs, a subset of the panel was tested on A- and C-compound action potentials recorded from isolated preparations of rat sciatic nerve. The results show that the major subtypes in the corresponding A- and C-fibers were NaV1.6 and 1.7, respectively. Ruled out as major players in both fiber types were NaV1.1, 1.2, and 1.3. These results are consistent with immunohistochemical findings of others. To our awareness this is the first report describing a qualitative pharmacological survey of TTX-sensitive NaV1 isoforms responsible for propagating action potentials in peripheral nerve. The panel of μ-conopeptides should be useful in identifying the functional contributions of NaV1 isoforms in other preparations. PMID:21652775

  13. Essential oil of Lippia alba and its main constituent citral block the excitability of rat sciatic nerves

    PubMed Central

    Sousa, D.G.; Sousa, S.D.G.; Silva, R.E.R.; Silva-Alves, K.S.; Ferreira-da-Silva, F.W.; Kerntopf, M.R.; Menezes, I.R.A.; Leal-Cardoso, J.H.; Barbosa, R.

    2015-01-01

    Lippia alba is empirically used for infusions, teas, macerates, and hydroalcoholic extracts because of its antispasmodic, analgesic, sedative, and anxiolytic effects. Citral is a mixture of trans-geranial and cis-neral and is the main constituent of L. alba essential oil and possesses analgesic, anxiolytic, anticonvulsant, and sedative effects. The present study evaluated the effects of the essential oil of L. alba (EOLa) and citral on compound action potentials (CAPs) in Wistar rat sciatic nerves. Both drugs inhibited CAP in a concentration-dependent manner. The calculated half-maximal inhibitory concentrations (IC50) of peak-to-peak amplitude were 53.2 µg/mL and 35.00 µg/mL (or 230 µM) for EOLa and citral, respectively. Peak-to-peak amplitude of the CAP was significantly reduced by 30 µg/mL EOLa and 10 µg/mL citral. EOLa and citral (at 60 and 30 µg/mL, values close to their respective IC50 for CAP blockade) significantly increased chronaxy and rheobase. The conduction velocity of the first and second CAP components was statistically reduced to ∼86% of control with 10 µg/mL EOLa and ∼90% of control with 3 µg/mL citral. This study showed that EOLa inhibited nerve excitability and this effect can be explained by the presence of citral in its composition. Both EOLa and citral showed inhibitory actions at lower concentrations compared with other essential oils and constituents with local anesthetic activity. In conclusion, these data demonstrate that EOLa and citral are promising agents in the development of new drugs with local anesthetic activity. PMID:26132093

  14. Can bedside patient-reported numbness predict postoperative ambulation ability for total knee arthroplasty patients with nerve block catheters?

    PubMed Central

    Mudumbai, Seshadri C.; Ganaway, Toni; Kim, T. Edward; Howard, Steven K.; Giori, Nicholas J.; Shum, Cynthia

    2016-01-01

    Background Adductor canal catheters offer advantages over femoral nerve catheters for knee replacement patients because they produce less quadriceps muscle weakness; however, applying adductor canal catheters in bedside clinical practice remains challenging. There is currently no patient-reported outcome that accurately predicts patients' physical function after knee replacement. The present study evaluates the validity of a relatively new patient-reported outcome, i.e., a numbness score obtained using a numeric rating scale, and assesses its predictive value on postoperative ambulation. Methods We conducted a retrospective cohort study pooling data from two previously-published clinical trials using identical research methodologies. Both studies recruited patients undergoing knee replacement; one studied adductor canal catheters while the other studied femoral nerve catheters. Our primary outcome was patient-reported numbness scores on postoperative day 1. We also examined postoperative day 1 ambulation distance and its association with postoperative numbness using linear regression, adjusting for age, body mass index, and physical status. Results Data from 94 subjects were included (femoral subjects, n = 46; adductor canal subjects, n = 48). Adductor canal patients reported decreased numbness (median [10th–90th percentiles]) compared to femoral patients (0 [0–5] vs. 4 [0–10], P = 0.001). Adductor canal patients also ambulated seven times further on postoperative day 1 relative to femoral patients. There was a significant association between postoperative day 1 total ambulation distance and numbness (Beta = –2.6; 95% CI: –4.5, –0.8, P = 0.01) with R2 = 0.1. Conclusions Adductor canal catheters facilitate improved early ambulation and produce less patient-reported numbness after knee replacement, but the correlation between these two variables is weak. PMID:26885299

  15. The role of lamina cribrosa cells in optic nerve head fibrosis in glaucoma.

    PubMed

    Wallace, Deborah M; O'Brien, Colm J

    2016-01-01

    Glaucoma is a chronic progressive optic neuropathy. There are extracellular matrix (ECM) changes associated with optic disc cupping in the optic nerve head (ONH) and subsequent visual field defects. The primary risk factor for onset and progression of glaucoma is raised intraocular pressure (IOP). Elevated IOP causes deformation at the ONH specifically at the lamina cribrosa (LC) region where there is also deposition of ECM causing the LC to initially undergo thickening and posterior migration with eventual shearing and collapse of the LC plates leading to a thin fibrotic connective tissue structure/scar. Cells that populate the LC region of the ONH are those cells that are positive for GFAP (the astrocytes) and those negative for GFAP (the LC cells). The LC cell plays an integral role in ECM remodelling producing ECM when exposed to high level mechanical stretch, TGF- β1 and a hypoxic environment. PMID:26675406

  16. International Federation of Societies for Surgery of the Hand Committee report: the role of nerve transfers in the treatment of neonatal brachial plexus palsy.

    PubMed

    Tse, Raymond; Kozin, Scott H; Malessy, Martijn J; Clarke, Howard M

    2015-06-01

    Nerve transfers have gained popularity in the treatment of adult brachial plexus palsy; however, their role in the treatment of neonatal brachial plexus palsy (NBPP) remains unclear. Brachial plexus palsies in infants differ greatly from those in adults in the patterns of injury, potential for recovery, and influences of growth and development. This International Federation of Societies for Surgery of the Hand committee report on NBPP is based upon review of the current literature. We found no direct comparisons of nerve grafting to nerve transfer for primary reconstruction of NBPP. Although the results contained in individual reports that use each strategy for treatment of Erb palsy are similar, comparison of nerve transfer to nerve grafting is limited by inconsistencies in outcomes reported, by multiple confounding factors, and by small numbers of patients. Although the role of nerve transfers for primary reconstruction remains to be defined, nerve transfers have been found to be effective and useful in specific clinical circumstances including late presentation, isolated deficits, failed primary reconstruction, and multiple nerve root avulsions. In the case of NBPP more severe than Erb palsy, nerve transfers alone are inadequate to address all of the deficits and should only be considered as adjuncts if maximal re-innervation is to be achieved. Surgeons who commit to care of infants with NBPP need to avoid an over-reliance on nerve transfers and should also have the capability and inclination for brachial plexus exploration and nerve graft reconstruction. PMID:25936735

  17. Treatment of Post-mastectomy Pain With Ambulatory Continuous Paravertebral Nerve Blocks: A Randomized, Triple-Masked, Placebo-Controlled Study

    PubMed Central

    Ilfeld, Brian M.; Madison, Sarah J.; Suresh, Preetham J.; Sandhu, NavParkash S.; Kormylo, Nicholas J.; Malhotra, Nisha; Loland, Vanessa J.; Wallace, Mark S.; Proudfoot, James A.; Morgan, Anya C.; Wen, Cindy H.; Wallace, Anne M.

    2013-01-01

    Background We aimed to determine with this randomized, triple-masked, placebo-controlled study if benefits are afforded by adding a multiple-day, ambulatory, continuous ropivacaine paravertebral nerve block to a single-injection ropivacaine paravertebral block following mastectomy. Methods Preoperatively, 60 subjects undergoing unilateral (n = 24) or bilateral (n = 36) mastectomy received either unilateral or bilateral paravertebral perineural catheter(s), respectively, inserted between the third and fourth thoracic transverse process(es). All subjects received an initial bolus of ropivacaine 0.5% (15 mL) via the catheter(s). Subjects were randomized to receive either perineural ropivacaine 0.4% or normal saline using portable infusion pump(s) [5 mL/h basal; 300 mL reservoir(s)]. Subjects remained hospitalized for at least 1 night and were subsequently discharged home where the catheter(s) were removed on postoperative day 3. Subjects were contacted by telephone on postoperative days 1, 4, 8, and 28. The primary end point was average pain (scale: 0–10) queried on postoperative day (POD) 1. Results Average pain queried on POD 1 for subjects receiving perineural ropivacaine (n=30) was a median (interquartile) of 2 (0–3), compared with 4 (1–5) for subjects receiving saline (n = 30; 95% CI difference in medians, −4.0 – −0.3; P = 0.021]. During this same time period, subjects receiving ropivacaine experienced a lower severity of breakthrough pain (5 [3–6] vs 7 [5–8]; P = 0.046) as well. As a result, subjects receiving perineural ropivacaine experienced less pain-induced physical and emotional dysfunction, as measured with the Brief Pain Inventory (lower score = less dysfunction): 14 (4–37) vs 57 (8–67) for subjects receiving perineural saline (P = 0.012). For the subscale that measures the degree of interference of pain on 7 domains, such as general activity and relationships, subjects receiving perineural saline reported a median score 10 times

  18. The effects of perineural dexmedetomidine on the pharmacodynamic profile of femoral nerve block: a dose-finding randomised, controlled, double-blind study.

    PubMed

    Abdulatif, M; Fawzy, M; Nassar, H; Hasanin, A; Ollaek, M; Mohamed, H

    2016-10-01

    This randomised, controlled, double-blind study investigated the effects of different doses of perineural dexmedetomidine on the pharmacodynamic profile of femoral nerve block in patients undergoing arthroscopic knee surgery. Ultrasound-guided femoral nerve block was performed before general anaesthesia using 25 ml of bupivacaine 0.5% combined with normal saline in the control group, and 25 μg, 50 μg or 75 μg of dexmedetomidine in three treatment groups (n = 15 for each group). All patients received a standard general anaesthetic and multimodal postoperative analgesic regimen. The use of the 50 μg and 75 μg dose levels of dexmedetomidine was associated with reduction of the onset time, extension of the duration of block, prolonged time to the first postoperative request for rescue analgesia, and reduced postoperative morphine requirements. The times to first request for postoperative analgesia were mean (SD) 10.8 (1.6) h in the control group and 11.0 (7.1), 21.8 (3.0) and 28.6 (10.0) in the 25 μg, 50 μg and 75 μg treatment groups, respectively. These times were significantly longer in the 50 μg and 75 μg treatment groups compared with the 25 μg (p < 0.0001) and control group (p < 0.0001). The total 24-h postoperative morphine consumption was 7.6 (5.1) mg in the control group, and 6.5 (3.5), 3.9 (3.4), 1.8 (2.6) in the 25 μg, 50 μg and 75 μg treatment groups, respectively. Postoperative morphine consumption was significantly higher in the control group compared with the 50 μg (p = 0.045) and the 75 μg (p = 0.001) treatment groups. The best analgesic profile was achieved at the 75 μg dose, but this was associated with increased risk of hypotension. PMID:27611039

  19. Nerve growth factor: role in growth, differentiation and controlling cancer cell development.

    PubMed

    Aloe, Luigi; Rocco, Maria Luisa; Balzamino, Bijorn Omar; Micera, Alessandra

    2016-01-01

    Recent progress in the Nerve Growth Factor (NGF) research has shown that this factor acts not only outside its classical domain of the peripheral and central nervous system, but also on non-neuronal and cancer cells. This latter observation has led to divergent hypothesis about the role of NGF, its specific distribution pattern within the tissues and its implication in induction as well as progression of carcinogenesis. Moreover, other recent studies have shown that NGF has direct clinical relevance in certain human brain neuron degeneration and a number of human ocular disorders. These studies, by suggesting that NGF is involved in a plethora of physiological function in health and disease, warrant further investigation regarding the true role of NGF in carcinogenesis. Based on our long-lasting experience in the physiopathology of NGF, we aimed to review previous and recent in vivo and in vitro NGF studies on tumor cell induction, progression and arrest. Overall, these studies indicate that the only presence of NGF is unable to generate cell carcinogenesis, both in normal neuronal and non-neuronal cells/tissues. However, it cannot be excluded the possibility that the co-expression of NGF and pro-carcinogenic molecules might open to different consequence. Whether NGF plays a direct or an indirect role in cell proliferation during carcinogenesis remains to demonstrate. PMID:27439311

  20. Stabilization of acetylcholine receptors at the neuromuscular synapse: the role of the nerve.

    PubMed

    Ramsay, D A; Drachman, D B; Drachman, R J; Stanley, E F

    1992-05-29

    The majority of acetylcholine receptors (AChRs) at innervated neuromuscular junctions (NMJs) are stable, with half-lives averaging about 11 days in rodent muscles. In addition to the stable AChRs, approximately 18% of AChRs at these innervated junctions are rapidly turned over (RTOs), with half lives of less than 24 h. We have postulated that RTOs may be precursors of stable AChRs, and that the motor nerve may influence their stabilization. This hypothesis was tested by: (i) labeling AChRs in mouse sternomastoid (SM) muscles with 125I-alpha-BuTx; (ii) denervating one SM muscle in each mouse, and (iii) following the fate of the labeled AChRs through a 5-day period when RTOs were either stabilized or degraded. The hypothesis predicts that denervation should preclude stabilization of RTOs, resulting in a deficit of stable AChRs in denervated muscles. The results showed a highly significant (P less than 0.002) deficit of stable AChRs in denervated as compared with innervated muscles. Control experiments excluded the possibility that this deficit could be attributed to independent accelerated degradation of either RTOs or pre-existing stable AChRs. The observed deficit was quantitatively consistent with the deficit predicted by a mathematical model based on interruption of stabilization following denervation. We conclude that: (i) the observed deficit after denervation of NMJs is due to failure of stabilization of pre-existing RTOs; (ii) RTOs at normally innervated NMJs are precursors of stable AChRs; (iii) stabilization occurs after the insertion of AChRs at NMJs, and (iv) motor nerves play a key role in stabilization of RTOs. The concept of receptor stabilization has important implications for understanding the biology of the neuromuscular junction and post-synaptic plasticity.

  1. Hyposensitivity to nerve stimulation in portal hypertensive rats: role of nitric oxide.

    PubMed

    Sieber, C C; Sumanovski, L T; Moll-Kaufmann, C; Stalder, G A

    1997-11-01

    Portal hypertension goes along with vascular hyporeactivity, partly mediated by nitric oxide (NO). Interactions between the adrenergic nervous system and NO in portal hypertension are undetermined. We tested (1) whether superior mesenteric arterial beds of portal hypertensive rats have an altered sensitivity to periarterial nerve stimulation (PNS) and (2) the role of NO in modulating nerve-stimulated responses. Vasopressor responses to PNS (Hz, 2-32) were similar in preparations of partial portal vein-ligated (PVL, n = 12) and control (CON, n = 12) rats (60.0 +/- 6.7 and 47.8 +/- 6.1 CmH2O respectively) for 24 Hz (NS), but sensitivity of vessels of portal hypertensive animals displayed a significant rightward shift [Hz needed for 50% of maximal response (HZ50) being 15.5 +/- 0.4 and 12.9 +/- 0.6 for PVL and CON respectively, P < 0.001]. NO formation inhibition by N omega-nitro-L-arginine (10(-4) mol L-1) significantly increased responses to PNS (P < 0.05), the absolute values for 24 Hz being 101.4 +/- 11.7 cmH2O for PVL (n = 8) and 86.4 +/- 11.4 cmH2O for CON (n = 7) (NS). NO formation inhibition reversed the hyposensitivity in preparations of PVL, Hz50 being 13.9 +/- 0.5 and 13.2 +/- 0.2 for PVL and CON respectively (NS). Adrenergic receptor antagonism with prazosin (10(-7) mol L-1) and yohimbine (10(-6) mol L-1) inhibited PNS-mediated vasopressor reactivity (n = 6 per group, P < 0.001), confirming the nervous origin of vasoconstrictor responses. It is concluded that (1) portal hypertension goes along with a significant hyposensitivity to PNS and (2) this hyposensitivity is reversed by NO-formation inhibition PMID:9395785

  2. Hyposensitivity to nerve stimulation in portal hypertensive rats: role of nitric oxide.

    PubMed

    Sieber, C C; Sumanovski, L T; Moll-Kaufmann, C; Stalder, G A

    1997-11-01

    Portal hypertension goes along with vascular hyporeactivity, partly mediated by nitric oxide (NO). Interactions between the adrenergic nervous system and NO in portal hypertension are undetermined. We tested (1) whether superior mesenteric arterial beds of portal hypertensive rats have an altered sensitivity to periarterial nerve stimulation (PNS) and (2) the role of NO in modulating nerve-stimulated responses. Vasopressor responses to PNS (Hz, 2-32) were similar in preparations of partial portal vein-ligated (PVL, n = 12) and control (CON, n = 12) rats (60.0 +/- 6.7 and 47.8 +/- 6.1 CmH2O respectively) for 24 Hz (NS), but sensitivity of vessels of portal hypertensive animals displayed a significant rightward shift [Hz needed for 50% of maximal response (HZ50) being 15.5 +/- 0.4 and 12.9 +/- 0.6 for PVL and CON respectively, P < 0.001]. NO formation inhibition by N omega-nitro-L-arginine (10(-4) mol L-1) significantly increased responses to PNS (P < 0.05), the absolute values for 24 Hz being 101.4 +/- 11.7 cmH2O for PVL (n = 8) and 86.4 +/- 11.4 cmH2O for CON (n = 7) (NS). NO formation inhibition reversed the hyposensitivity in preparations of PVL, Hz50 being 13.9 +/- 0.5 and 13.2 +/- 0.2 for PVL and CON respectively (NS). Adrenergic receptor antagonism with prazosin (10(-7) mol L-1) and yohimbine (10(-6) mol L-1) inhibited PNS-mediated vasopressor reactivity (n = 6 per group, P < 0.001), confirming the nervous origin of vasoconstrictor responses. It is concluded that (1) portal hypertension goes along with a significant hyposensitivity to PNS and (2) this hyposensitivity is reversed by NO-formation inhibition

  3. Leptin differentially increases sympathetic nerve activity and its baroreflex regulation in female rats: role of oestrogen

    PubMed Central

    Shi, Zhigang; Brooks, Virginia L

    2015-01-01

    in ovariectomized rats, but its effects were normalized with 4 days of oestrogen treatment. Bilateral nanoinjection of SHU9119 into the paraventricular nucleus of the hypothalamus (PVN), to block α-melanocyte-stimulating hormone (α-MSH) type 3 and 4 receptors, decreased LSNA in leptin-treated pro-oestrus but not dioestrus rats. Unlike leptin, i.c.v. insulin infusion increased basal and baroreflex control of LSNA and HR similarly in pro-oestrus and dioestrus rats; these responses did not differ from those in male rats. We conclude that, in female rats, leptin's stimulatory effects on SNA are differentially enhanced by oestrogen, at least in part via an increase in α-MSH activity in the PVN. These data further suggest that the actions of leptin and insulin to increase the activity of various sympathetic nerves occur via different neuronal pathways or cellular mechanisms. These results may explain the poor correlation in females of SNA with adiposity, or of MAP with leptin. PMID:25398524

  4. Polymer Coatings of Cochlear Implant Electrode Surface - An Option for Improving Electrode-Nerve-Interface by Blocking Fibroblast Overgrowth.

    PubMed

    Hadler, C; Aliuos, P; Brandes, G; Warnecke, A; Bohlmann, J; Dempwolf, W; Menzel, H; Lenarz, T; Reuter, G; Wissel, K

    2016-01-01

    Overgrowth of connective tissue and scar formation induced by the electrode array insertion increase the impedance and, thus, diminish the interactions between neural probes as like cochlear implants (CI) and the target tissue. Therefore, it is of great clinical interest to modify the carrier material of the electrodes to improve the electrode nerve interface for selective cell adhesion. On one side connective tissue growth needs to be reduced to avoid electrode array encapsulation, on the other side the carrier material should not compromise the interaction with neuronal cells. The present in vitro-study qualitatively and quantitatively characterises the interaction of fibroblasts, glial cells and spiral ganglion neurons (SGN) with ultrathin poly(N,N-dimethylacrylamide) (PDMAA), poly(2-ethyloxazoline) (PEtOx) and poly([2-methacryloyloxy)ethyl]trimethylammoniumchlorid) (PMTA) films immobilised onto glass surfaces using a photoreactive anchor layer. The layer thickness and hydrophilicity of the polymer films were characterised by ellipsometric and water contact angle measurement. Moreover the topography of the surfaces was investigated using atomic force microscopy (AFM). The neuronal and non-neuronal cells were dissociated from spiral ganglions of postnatal rats and cultivated for 48 h on top of the polymer coatings. Immunocytochemical staining of neuronal and intermediary filaments revealed that glial cells predominantly attached on PMTA films, but not on PDMAA and PEtOx monolayers. Hereby, strong survival rates and neurite outgrowth were only found on PMTA, whereas PDMAA and PEtOx coatings significantly reduced the SG neuron survival and neuritogenesis. As also shown by scanning electron microscopy (SEM) SGN strongly survived and retained their differentiated phenotype only on PMTA. In conclusion, survival and neuritogenesis of SGN may be associated with the extent of the glial cell growth. Since PMTA was the only of the polar polymers used in this study bearing

  5. Polymer Coatings of Cochlear Implant Electrode Surface – An Option for Improving Electrode-Nerve-Interface by Blocking Fibroblast Overgrowth

    PubMed Central

    Hadler, C.; Aliuos, P.; Brandes, G.; Warnecke, A.; Bohlmann, J.; Dempwolf, W.; Menzel, H.; Lenarz, T.; Reuter, G.; Wissel, K.

    2016-01-01

    Overgrowth of connective tissue and scar formation induced by the electrode array insertion increase the impedance and, thus, diminish the interactions between neural probes as like cochlear implants (CI) and the target tissue. Therefore, it is of great clinical interest to modify the carrier material of the electrodes to improve the electrode nerve interface for selective cell adhesion. On one side connective tissue growth needs to be reduced to avoid electrode array encapsulation, on the other side the carrier material should not compromise the interaction with neuronal cells. The present in vitro-study qualitatively and quantitatively characterises the interaction of fibroblasts, glial cells and spiral ganglion neurons (SGN) with ultrathin poly(N,N-dimethylacrylamide) (PDMAA), poly(2-ethyloxazoline) (PEtOx) and poly([2-methacryloyloxy)ethyl]trimethylammoniumchlorid) (PMTA) films immobilised onto glass surfaces using a photoreactive anchor layer. The layer thickness and hydrophilicity of the polymer films were characterised by ellipsometric and water contact angle measurement. Moreover the topography of the surfaces was investigated using atomic force microscopy (AFM). The neuronal and non-neuronal cells were dissociated from spiral ganglions of postnatal rats and cultivated for 48 h on top of the polymer coatings. Immunocytochemical staining of neuronal and intermediary filaments revealed that glial cells predominantly attached on PMTA films, but not on PDMAA and PEtOx monolayers. Hereby, strong survival rates and neurite outgrowth were only found on PMTA, whereas PDMAA and PEtOx coatings significantly reduced the SG neuron survival and neuritogenesis. As also shown by scanning electron microscopy (SEM) SGN strongly survived and retained their differentiated phenotype only on PMTA. In conclusion, survival and neuritogenesis of SGN may be associated with the extent of the glial cell growth. Since PMTA was the only of the polar polymers used in this study bearing

  6. Role of TrkB in the anxiolytic-like and antidepressant-like effects of vagal nerve stimulation: Comparison with desipramine.

    PubMed

    Shah, A P; Carreno, F R; Wu, H; Chung, Y A; Frazer, A

    2016-05-13

    A current hypothesis regarding the mechanism of antidepressant (AD) action suggests the involvement of brain-derived neurotrophic factor (BDNF). Consistent with this hypothesis, the receptor for BDNF (and neurotrophin 4/5 (NT-4/5)), Tropomyosin-related kinase B (TrkB), is activated in rodents by treatment with classical AD drugs. Vagal nerve stimulation (VNS), a therapy for treatment resistant depression (TRD), also activates TrkB in rodents. However, the role of this receptor in the therapeutic effects of VNS is unclear. In the current study, the involvement of TrkB in the effects of VNS was investigated in rats using its inhibitor, K252a. Anxiolytic-like and AD-like effects were analyzed using the novelty suppressed feeding test (NSFT) and forced swim test (FST), respectively. K252a blocked the anxiolytic-like effect of chronic VNS treatment and the AD-like effect of acute VNS treatment. By contrast, blocking TrkB did not prevent either the anxiolytic-like or AD-like effect of chronic treatment with desipramine (DMI), a selective noradrenergic reuptake inhibitor; it did, however, block the acute effect of DMI in the FST. To examine whether the activation of TrkB caused by either VNS or DMI is ligand-dependent, use was made of TrkB-Fc, a molecular scavenger for ligands of TrkB. Intraventricular administration of TrkB-Fc blocked the acute activation of TrkB induced by either treatment, indicating that treatment-induced activation of this receptor is ligand-dependent. The behavioral results highlight differences in the involvement of TrkB in the chronic effects of an AD drug and a stimulation therapy as well as its role in acute versus chronic effects of DMI. PMID:26899129

  7. The protein kinase A regulatory subunit R1A (Prkar1a) plays critical roles in peripheral nerve development.

    PubMed

    Guo, Li; Lee, Audrey A; Rizvi, Tilat A; Ratner, Nancy; Kirschner, Lawrence S

    2013-11-13

    Signaling through cAMP has been implicated in Schwann cell (SC) proliferation and myelination, but the signaling pathway components downstream of cAMP required for SC function remain unknown. Protein kinase A (PKA) is a potential downstream effector of cAMP. Here, we induced loss of Prkar1a, the gene encoding the type 1A regulatory subunit of PKA, in SC to study its role in nerve development; loss of Prkar1a is predicted to elevate PKA activity. Conditional Prkar1a knock-out in mouse SC (Prkar1a-SCKO) resulted in a dramatic and persistent axonal sorting defect, and unexpectedly decreased SC proliferation in Prkar1a-SCKO nerves in vivo. Effects were cell autonomous as they were recapitulated in vitro in Prkar1a-SCKO SC, which showed elevated PKA activity. In the few SCs sorted into 1:1 relationships with axons in vivo, SC myelination was premature in Prkar1a-SCKO nerves, correlating with global increase in the cAMP-regulated transcription factor Oct-6 and expression of myelin basic protein. These data reveal a previously unknown role of PKA in axon sorting, an unexpected inhibitory role of PKA on SC cell proliferation in vivo and define the importance of Prkar1a in peripheral nerve development. PMID:24227708

  8. The role of spinal GABAergic circuits in the control of phrenic nerve motor output

    PubMed Central

    Ghali, Michael G. Z.; Rogers, Robert F.

    2015-01-01

    While supraspinal mechanisms underlying respiratory pattern formation are well characterized, the contribution of spinal circuitry to the same remains poorly understood. In this study, we tested the hypothesis that intraspinal GABAergic circuits are involved in shaping phrenic motor output. To this end, we performed bilateral phrenic nerve recordings in anesthetized adult rats and observed neurogram changes in response to knocking down expression of both isoforms (65 and 67 kDa) of glutamate decarboxylase (GAD65/67) using microinjections of anti-GAD65/67 short-interference RNA (siRNA) in the phrenic nucleus. The number of GAD65/67-positive cells was drastically reduced on the side of siRNA microinjections, especially in the lateral aspects of Rexed's laminae VII and IX in the ventral horn of cervical segment C4, but not contralateral to microinjections. We hypothesize that intraspinal GABAergic control of phrenic output is primarily phasic, but also plays an important role in tonic regulation of phrenic discharge. Also, we identified respiration-modulated GABAergic interneurons (both inspiratory and expiratory) located slightly dorsal to the phrenic nucleus. Our data provide the first direct evidence for the existence of intraspinal GABAergic circuits contributing to the formation of phrenic output. The physiological role of local intraspinal inhibition, independent of descending direct bulbospinal control, is discussed. PMID:25833937

  9. [Influence of beta block and autonomic nerve block on the recovery time of the sinus node in sick sinus syndrome and carotid sinus syndrome].

    PubMed

    Brignole, M; Sartore, B; Barra, M; Menozzi, C; Monducci, I; Bertulla, A

    1984-10-01

    In order to evaluate the relative role of the automatic nervus system and of the intrinsic electrophysiologic properties on the sinus node function, we measured the corrected sinus node recovery time before and after autonomic nervous system blockade in 24 patients. Fourteen had a sick sinus syndrome, five had a carotid sinus syncope, two had syncope of unknown origin associated with bradycardia. Beta blockade was obtained by infusing metoprolol intravenously at a dosage of 0.2 mg/kg; complete automatic blockade was achieved by further i.v. administration of atropine at a dosage of 0.04 mg/kg. After beta blockade, the corrected sinus node recovery time increased in patients with sick sinus syndrome and intrinsic slow heart rate, whereas it decreased in patients with carotid sinus syncope or with syncope and bradycardia. In patients with sick sinus syndrome and normal intrinsic heart rate the response was variable. A positive direct correlation was found between the changes of the corrected sinus node recovery time induced by beta blockade and those induced by autonomic blockade; that is, both either prolonged or shortened the corrected sinus node recovery time. The changes of the corrected sinus node recovery time after beta blockade alone were inversely correlated with the intrinsic heart rate. We conclude that patients with intrinsic depression of the sinus node have an increased sympathetic tone.

  10. Transforaminal ligament may play a role in lumbar nerve root compression of foraminal stenosis.

    PubMed

    Qian, Yu; Qin, An; Zheng, Ming H

    2011-12-01

    Lumbar foraminal stenosis is a common pathological change, and lumbar nerve root compression in stenotic foramina was recently considered as one of the main causes of low back pain and leg pain. However, the exact mechanism of lumbar nerve root compression in foramina is still not clear. Previous studies indicated that loss of the intervertebral disc height could reduce the cross-sectional area of lumbar foramina, while lumbar nerve root compression by boundaries of foramina has not been observed in experimental reduction of the intervertebral disc height. Given the close anatomic relationship between transforaminal ligaments and lumbar nerve roots, we hypothesize that transforaminal ligament can be the leading cause of lumbar nerve root compression in foraminal stenosis. We also propose that there are two possible mechanisms of lumbar nerve root compression by transforaminal ligaments: (1) nerve roots are compressed by the transforaminal ligament which moves downward with the loss of the intervertebral disc height; (2) pathological transforaminal ligaments increase the risk of nerve root compression in foramina.

  11. Urokinase Plasminogen Receptor and the Fibrinolytic Complex Play a Role in Nerve Repair after Nerve Crush in Mice, and in Human Neuropathies

    PubMed Central

    Rivellini, Cristina; Dina, Giorgia; Porrello, Emanuela; Cerri, Federica; Scarlato, Marina; Domi, Teuta; Ungaro, Daniela; Carro, Ubaldo Del; Bolino, Alessandra; Quattrini, Angelo; Comi, Giancarlo; Previtali, Stefano C.

    2012-01-01

    Remodeling of extracellular matrix (ECM) is a critical step in peripheral nerve regeneration. In fact, in human neuropathies, endoneurial ECM enriched in fibrin and vitronectin associates with poor regeneration and worse clinical prognosis. Accordingly in animal models, modification of the fibrinolytic complex activity has profound effects on nerve regeneration: high fibrinolytic activity and low levels of fibrin correlate with better nerve regeneration. The urokinase plasminogen receptor (uPAR) is a major component of the fibrinolytic complex, and binding to urokinase plasminogen activator (uPA) promotes fibrinolysis and cell movement. uPAR is expressed in peripheral nerves, however, little is known on its potential function on nerve development and regeneration. Thus, we investigated uPAR null mice and observed that uPAR is dispensable for nerve development, whereas, loss of uPAR affects nerve regeneration. uPAR null mice showed reduced nerve repair after sciatic nerve crush. This was a consequence of reduced fibrinolytic activity and increased deposition of endoneurial fibrin and vitronectin. Exogenous fibrinolysis in uPAR null mice rescued nerve repair after sciatic nerve crush. Finally, we measured the fibrinolytic activity in sural nerve biopsies from patients with peripheral neuropathies. We showed that neuropathies with defective regeneration had reduced fibrinolytic activity. On the contrary, neuropathies with signs of active regeneration displayed higher fibrinolytic activity. Overall, our results suggest that enforced fibrinolysis may facilitate regeneration and outcome of peripheral neuropathies. PMID:22363796

  12. Role of Stromal Cell-Derived Factor-1 Expression in the Injured Mouse Auditory Nerve

    PubMed Central

    Kilpatrick, Lauren A.; Zhu, Juhong; Lee, Fu-Shing; Lang, Hainan

    2014-01-01

    Objective The degeneration of hair cells and spiral ganglion neurons (SGNs) is an important pathologic process in the development of sensorineural hearing loss. In a murine model, predictable and reproducible damage to SGNs occurs through the application of ouabain to the round window. Recent evidence has shown that the chemokine stromal cell–derived factor-1 (SDF-1) is a potent chemoattractant of hematopoietic stem cells (HSCs) and provides trophic support to injured tissues during development and maturation. The hypothesis for the current study is that expression of SDF-1 plays an important role in protecting SGNs and preventing further degeneration in the setting of cochlear injury. Study Design Prospective, controlled. Setting Academic research laboratory. Subject and Methods Auditory brainstem response (ABR) and the expression of SDF-1 mRNA and protein were examined 1, 3, 7, 14, and 30 days after application of ouabain in 35 adult mice. Results Following ouabain application, real-time reverse-transcription polymerase chain reaction for SDF demonstrates increased mRNA expression following ouabain injury in nontransplanted mice. A significant increase in SDF protein expression was also observed using immunolabeling techniques and Western blot analysis. Conclusions SDF-1 expression is increased in the auditory nerve following cochlear injury. Further knowledge about the cochlear microenvironment, including SDF-1, is critical to maximizing HSC engraftment in the injured cochlea and providing a therapeutic option for sensorineural hearing loss. PMID:21947792

  13. Comparative Effects of Periarticular Multimodal Drug Injection and Single-Shot Femoral Nerve Block on Pain Following Total Knee Arthroplasty and Factors Influencing Their Effectiveness

    PubMed Central

    Nakagawa, Shuji; Inoue, Hiroaki; Kan, Hiroyuki; Hino, Manabu; Ichimaru, Shohei; Ikoma, Kazuya; Fujiwara, Hiroyoshi; Amaya, Fumimasa; Sawa, Teiji; Kubo, Toshikazu

    2016-01-01

    Purpose This study compared the analgesic effects of local infiltration analgesia (LIA) and femoral nerve block (FNB) after total knee arthroplasty (TKA) and assessed factors associated with analgesia obtained by these two methods. Materials and Methods Study subjects included 66 patients (72 knees) who underwent TKA for osteoarthritis of the knee. Pain visual analogue scale (VAS), the amount of analgesics used, number of days to achieve 90° of flexion of the knee joint, date of initiating parallel-bar walking, range of motion of the knee joint at discharge, and adverse events were investigated. Results The VAS scores did not differ significantly between two groups, whereas the amount of analgesics used was significantly lower in the LIA group. Preoperative flexion contracture was significantly more severe in the LIA group with high VAS compared with low VAS. No serious adverse event occurred in the LIA or FNB group. Conclusions The lower analgesic usage in the LIA group than the FNB group indicates that the analgesic effect of LIA was greater than that of singleshot FNB after TKA. There were no serious complications in either group. The postoperative analgesic effect of LIA was smaller in patients with severe than less severe preoperative flexion contracture.

  14. Comparative Effects of Periarticular Multimodal Drug Injection and Single-Shot Femoral Nerve Block on Pain Following Total Knee Arthroplasty and Factors Influencing Their Effectiveness

    PubMed Central

    Nakagawa, Shuji; Inoue, Hiroaki; Kan, Hiroyuki; Hino, Manabu; Ichimaru, Shohei; Ikoma, Kazuya; Fujiwara, Hiroyoshi; Amaya, Fumimasa; Sawa, Teiji; Kubo, Toshikazu

    2016-01-01

    Purpose This study compared the analgesic effects of local infiltration analgesia (LIA) and femoral nerve block (FNB) after total knee arthroplasty (TKA) and assessed factors associated with analgesia obtained by these two methods. Materials and Methods Study subjects included 66 patients (72 knees) who underwent TKA for osteoarthritis of the knee. Pain visual analogue scale (VAS), the amount of analgesics used, number of days to achieve 90° of flexion of the knee joint, date of initiating parallel-bar walking, range of motion of the knee joint at discharge, and adverse events were investigated. Results The VAS scores did not differ significantly between two groups, whereas the amount of analgesics used was significantly lower in the LIA group. Preoperative flexion contracture was significantly more severe in the LIA group with high VAS compared with low VAS. No serious adverse event occurred in the LIA or FNB group. Conclusions The lower analgesic usage in the LIA group than the FNB group indicates that the analgesic effect of LIA was greater than that of singleshot FNB after TKA. There were no serious complications in either group. The postoperative analgesic effect of LIA was smaller in patients with severe than less severe preoperative flexion contracture. PMID:27595078

  15. The role of water in the structure of peripheral nerve myelin.

    PubMed

    FINEAN, J B

    1957-01-25

    In the study of the drying kinetics of nerve fibres, at least five "phases" of water evaporation can be distinguished. A consideration of the accompanying changes in low-angle x-ray diffraction patterns permits a tentative identification of the "phases" and a quantitative interpretation of the data in terms of the water distribution in nerve fibres. These results suggest that the myelin sheath of frog sciatic nerve contains 40 to 50 per cent water, and it is suggested further that the greater part of this water is "organised" in relation to the hydrophilic groups of the lipide and protein components.

  16. Prognostic roles for fibroblast growth factor receptor family members in malignant peripheral nerve sheath tumor

    PubMed Central

    Song, Fengju; Zheng, Hong; Chen, Kexin; Zhang, Wei; Yang, Jilong

    2016-01-01

    Background Malignant peripheral nerve sheath tumors (MPNST) are rare, highly malignant, and poorly understood sarcomas. The often poor outcome of MPNST highlights the necessity of identifying prognostic predictors for this aggressive sarcoma. Here, we investigate the role of fibroblast growth factor receptor (FGFR) family members in human MPNSTs. Results aCGH and bioinformatics analysis identified frequent amplification of the FGFR1 gene. FISH analysis revealed that 26.9% MPNST samples had amplification of FGFR1, with both focal and polysomy patterns observed. IHC identified that FGFR1 protein expression was positively correlated with FGFR1 gene amplification. High expression of FGFR1 protein was associated with better overall survival (OS) and was an independent prognostic predictor for OS of MPNST patients. Additionally, combined expression of FGFR1 and FGFR2 protein characterized a subtype of MPNST with better OS. FGFR4 protein was expressed 82.3% of MPNST samples, and was associated with poor disease-free survival. Materials and Methods We performed microarray-based comparative genomic hybridization (aCGH) profiling of two cohorts of primary MPNST tissue samples including 25 patients treated at The University of Texas MD Anderson Cancer Center and 26 patients from Tianjin Medical University Cancer Institute and Hospital. Fluorescence in situ hybridization (FISH) was used to validate the gene amplification detected by aCGH analysis. Another cohort of 63 formalin-fixed paraffin-embedded MPNST samples (including 52 samples for FISH assay) was obtained to explore FGFR1, 2, 3, and 4 protein expression by immunohistochemical (IHC) analysis. Conclusions Our integrated genomic and molecular studies provide evidence that FGFRs play different prognostic roles in MPNST. PMID:26993773

  17. Effect of Oral Premedication on the Efficacy of Inferior Alveolar Nerve Block in Patients with Symptomatic Irreversible Pulpitis: A Prospective, Double-Blind, Randomized Controlled Clinical Trial

    PubMed Central

    Saha, Suparna Ganguly; Dubey, Sandeep; Kala, Shubham; Misuriya, Abhinav; Kataria, Devendra

    2016-01-01

    Introduction It is generally accepted that achieving complete anaesthesia with an Inferior Alveolar Nerve Block (IANB) in mandibular molars with symptomatic irreversible pulpitis is more challenging than for other teeth. Therefore, administration of Non-Steroidal Anti-Inflammatory Agents (NSAIDs) 1 hour prior to anaesthetic administration has been proposed as a means to increase the efficacy of the IANB in such patients. Aim The purpose of this prospective, double-blind, randomized clinical trial was to determine the effect of administration of oral premedication with ketorolac (KETO) and diclofenac potassium (DP) on the efficacy of IANB in patients with irreversible pulpitis. Materials and Methods One hundred and fifty patients with irreversible pulpitis were evaluated preoperatively for pain using Heft Parker visual analogue scale, after which they were randomly divided into three groups. The subjects received identical tablets of ketorolac, diclofenac pottasium or cellulose powder (placebo), 1 hour prior to administration of IANB with 2% lidocaine containing 1:200 000 epinephrine. Lip numbness as well as positive and negative responses to cold test were ascertained. Additionally pain score of each patient was recorded during cavity preparation and root canal instrumentation. Success was defined as the absence of pain or mild pain based on the visual analog scale readings. The data was analysed using One-Way Anova, Post-Hoc Tukey pair wise, Paired T – Test and chi-square test. Trial Registery Number is 4722/2015 for this clinical trial study. Results There were no significant differences with respect to age (p =0.098), gender (p = 0.801) and pre-VAS score (DP-KETO p=0.645, PLAC-KETO p =0.964, PLAC-DP p = 0.801) between the three groups. All patients had subjective lip anaesthesia with the IAN blocks. Patients of all the three groups reported a significant decrease in active pain after local anaesthesia (p< 0.05). The post injection VAS Score was least in group

  18. The role of tortuosity on ion conduction in block copolymer electrolyte thin films

    NASA Astrophysics Data System (ADS)

    Kambe, Yu; Arges, Christopher G.; Nealey, Paul F.

    This talk discusses the role of grain tortuosity on ion conductivity in block copolymer electrolyte (BCE) thin films. In particular, we studied lamellae forming BCEs with both domains oriented perpendicular to the substrate surface and connected directly from one electrode to another - i.e., tortuosity of one. The BCE is composed of ion-conducting, poly(2-vinyl n-methylpyridinium) blocks and non-ionic polystyrene blocks. Prior to creating the BCE, the pristine block copolymer, poly(styrene- b-2-vinyl pyridine), was directly self-assembled (DSA) on topographical or chemical patterns via graphoepitaxy and chemoepitaxy. A chemical vapor infiltration reaction modified the P2VP block into positively charged, fixed quaternary ammonium groups paired with mobile counteranions. The graphoepitaxy process utilized topographical interdigitated gold nanoelectrodes (100s of nanometers spacing between electrodes) created via e-beam lithography. Alternatively, chemical patterns had gold electrodes incorporated into them with 10s to 100s of microns spacing using conventional optical lithography. The interdigitated gold electrodes enabled in-plane ion conductivity measurements of the DSA BCEs to study the role of grain tortuosity on ion conductivity. U.S. Department of Energy Office of Science: Contract No. DE-AC02-06CH11357.

  19. The pathogenic role of transforming growth factor-β2 in glaucomatous damage to the optic nerve head.

    PubMed

    Fuchshofer, Rudolf

    2011-08-01

    In patients with primary open angle glaucoma (POAG), the optic nerve head (ONH) shows characteristic cupping correlated with visual field defects. The progressive optic neuropathy is characterized by irreversible loss of retinal ganglion cells (RGC). The critical risk factor for axonal damage at the ONH is an elevated intraocular pressure (IOP). The increase in IOP correlates with axonal loss in the ONH, which might be due to an impaired axoplasmatic flow leading to the loss of RGCs. Damage to the optic nerve is thought to occur in the lamina cribrosa (LC) region of the ONH, which is composed of characteristic sieve-like connective tissue cribriform plates through which RGC axons exit the eye. The cupping of the optic disc, and the compression and excavation of LC are characteristic signs of glaucomatous ONH remodelling. In ONH of POAG patients a disorganized distribution and deposition of elastic fibers and a typical pronounced thickening of the connective tissue septae surrounding the optic nerve fibers is found. Transforming growth factor (TGF)-β2 could be one of the pathogenic factors responsible for the structural alterations in POAG patients as the TGF-β2 levels in the ONH of glaucomatous eyes are elevated as well as in the aqueous homour. TGF-β2 leads to an increased synthesis of extracellular matrix (ECM) molecules mediated by connective tissue growth factor and to an impaired ECM degradation in cultured ONH astrocytes. Bone morphogenetic protein (BMP)-4 effectively antagonizes the effects of TGF-β2 on matrix deposition. The BMP antagonist gremlin blocks this inhibition, allowing TGF-β2 stimulation of ECM synthesis. Overall, the ECM in the ONH is kept in balance in the OHN by factors that augment or block the activity of TGF-β2.

  20. Key roles for chain flexibility in block copolymer membranes that contain pores or make tubes.

    PubMed

    Srinivas, Goundla; Discher, Dennis E; Klein, Michael L

    2005-12-01

    Block copolymer amphiphiles that self-assemble into membranes present robust and functionalizable alternatives to biological assemblies. Coarse-grained molecular dynamics shows that thick bilayers of A-B copolymers accommodate protein-like channels and also tend to regulate transport. This occurs as flexible, hydrophilic A chains insert into the pore and obstruct water entry. A-B-A triblocks that exploit "hairpin" and "straight" conformations also show assembly into novel nanotubules and further highlight the key roles for chain flexibility in biomimetic block copolymer assemblies.

  1. Amphiphilic peptides and their cross-disciplinary role as building blocks for nanoscience.

    PubMed

    Cavalli, Silvia; Albericio, Fernando; Kros, Alexander

    2010-01-01

    Peptides are particularly attractive as molecular building blocks in the bottom-up fabrication of supramolecular structures based on self-assembly and have potential in many important applications in the fields of biotechnology and bioengineering. In the first part of this critical review the main categories of peptide-based amphiphiles will be discussed by showing some relevant examples, which demonstrate the importance of amphiphilic peptides as molecular building blocks for nanostructures. In the second part of this review we will review the cross-disciplinary role of peptide-based supramolecular nanoarchitectures ranging from chemistry to biology, medicine, materials science, and engineering through discussing several examples of applied nanomaterials (216 references).

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

    SciTech Connect

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

    2014-01-01

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

  3. Differential roles of stretch-sensitive pelvic nerve afferents innervating mouse distal colon and rectum

    PubMed Central

    Brumovsky, Pablo R.; Gebhart, Gerald F.

    2010-01-01

    Information about colorectal distension (i.e., colorectal dilation by increased intraluminal pressure) is primarily encoded by stretch-sensitive colorectal afferents in the pelvic nerve (PN). Despite anatomic differences between rectum and distal colon, little is known about the functional roles of colonic vs. rectal afferents in the PN pathway or the quantitative nature of mechanosensory encoding. We utilized an in vitro mouse colorectum-PN preparation to investigate pressure-encoding characteristics of colorectal afferents. The colorectum with PN attached was dissected, opened longitudinally, and pinned flat in a Sylgard-lined chamber. Action potentials of afferent fibers evoked by circumferential stretch (servo-controlled force actuator) were recorded from the PN. Stretch-sensitive fibers were categorized into the following four groups: colonic muscular, colonic muscular/mucosal, rectal muscular, and rectal muscular/mucosal. Seventy-nine stretch-sensitive PN afferents evenly distributed into the above four groups were studied. Rectal muscular afferents had significantly greater stretch-responses than the other three groups. Virtually all rectal afferents (98%) had low thresholds for response and encoded stimulus intensity into the noxious range without obvious saturation. Most colonic afferents (72%) also had low thresholds (<14 mmHg), but a significant proportion (28%) had high thresholds (>18 mmHg) for response. These high-threshold colonic afferents were sensitized to stretch by inflammatory soup; response threshold was significantly reduced (from 23 to 12 mmHg), and response magnitude significantly increased. These results suggest that the encoding of mechanosensory information differs between colonic and rectal stretch-sensitive PN afferents. Rectal afferents have a wide response range to stretch, whereas high-threshold colonic afferents likely contribute to visceral nociception. PMID:20075141

  4. Differential roles of stretch-sensitive pelvic nerve afferents innervating mouse distal colon and rectum.

    PubMed

    Feng, Bin; Brumovsky, Pablo R; Gebhart, Gerald F

    2010-03-01

    Information about colorectal distension (i.e., colorectal dilation by increased intraluminal pressure) is primarily encoded by stretch-sensitive colorectal afferents in the pelvic nerve (PN). Despite anatomic differences between rectum and distal colon, little is known about the functional roles of colonic vs. rectal afferents in the PN pathway or the quantitative nature of mechanosensory encoding. We utilized an in vitro mouse colorectum-PN preparation to investigate pressure-encoding characteristics of colorectal afferents. The colorectum with PN attached was dissected, opened longitudinally, and pinned flat in a Sylgard-lined chamber. Action potentials of afferent fibers evoked by circumferential stretch (servo-controlled force actuator) were recorded from the PN. Stretch-sensitive fibers were categorized into the following four groups: colonic muscular, colonic muscular/mucosal, rectal muscular, and rectal muscular/mucosal. Seventy-nine stretch-sensitive PN afferents evenly distributed into the above four groups were studied. Rectal muscular afferents had significantly greater stretch-responses than the other three groups. Virtually all rectal afferents (98%) had low thresholds for response and encoded stimulus intensity into the noxious range without obvious saturation. Most colonic afferents (72%) also had low thresholds (<14 mmHg), but a significant proportion (28%) had high thresholds (>18 mmHg) for response. These high-threshold colonic afferents were sensitized to stretch by inflammatory soup; response threshold was significantly reduced (from 23 to 12 mmHg), and response magnitude significantly increased. These results suggest that the encoding of mechanosensory information differs between colonic and rectal stretch-sensitive PN afferents. Rectal afferents have a wide response range to stretch, whereas high-threshold colonic afferents likely contribute to visceral nociception.

  5. Dorsal Penile Nerve Block With Ropivacaine-Reduced Postoperative Catheter-Related Bladder Discomfort in Male Patients After Emergence of General Anesthesia

    PubMed Central

    Li, Jing-yi; Yi, Ming-liang; Liao, Ren

    2016-01-01

    Abstract Catheter-related bladder discomfort (CRBD) is a distressing symptom complex after surgery, especially in male patients who have had urinary catheterization under general anesthesia. In this prospective, randomized, controlled trial, we compared dorsal penile nerve block (DPNB) with 0.33% ropivacaine with intravenous tramadol 1.5 mg kg−1 in prevention of CRBD, as well as the incidences of postoperative side effects. Fifty-eight male patients aged 18 to 50 years, undergoing elective liver surgery and limb surgery with urinary catheterization, were enrolled and divided randomly into 2 groups. In the DPNB group, patients were given dorsal penile nerve block with 15 mL of 0.33% ropivacaine, and in the tramadol intravenous administration (TRAM) group, patients were given 1.5 mg kg−1 tramadol after the completion of surgery before extubation. The primary outcome was the incidence of CRBD, and the secondary outcomes included the severity of CRBD, postoperative side effects, postoperative pain, and the acceptance of urinary catheterization. Patients were evaluated upon arrival to postanesthetic care unit (PACU), at 0.5, 1, 2, 4, and 6 hours after patients’ arrival in the PACU for outcomes. The incidence of CRBD was significantly lower in the DPNB group than in the TRAM group, either upon arrival to PACU (10.3% vs 37.9%, P = 0.015), or at 0.5 hours (3.4% vs 34.5%, P = 0.003), 1 hours (3.4% vs 37.9%, P = 0.001), 2 hours (6.9% vs 34.5%, P = 0.010), and 4 hours (6.9% vs 27.6%, P = 0.039) after patients’ arrival in PACU. Compared with the TRAM group, the severity of postoperative CRBD upon arrival to PACU (P = 0.011) and at 0.5 hours (P = 0.005), 1 hours (P = 0.002), 2 hours (P = 0.005), 4 hours (P = 0.017), and 6 hours (P = 0.047) after patients’ arrival in PACU were all significantly reduced in the DPNB group. The incidences of postoperative nausea, vomiting, dizziness, and sedation

  6. Articaine and mepivacaine buccal infiltration in securing mandibular first molar pulp anesthesia following mepivacaine inferior alveolar nerve block: A randomized, double-blind crossover study

    PubMed Central

    Gazal, Giath; Alharbi, Abdullah Muteb; Al-Samadani, Khalid HidayatAllah; Kanaa, Mohammad Dib

    2015-01-01

    Aims: A crossover double-blind, randomized study was designed to explore the efficacy of 2% mepivacaine with 1:100,000 adrenaline buccal infiltration and 4% articaine with 1:100,000 adrenaline buccal infiltration following 2% mepivacaine with 1:100,000 adrenaline inferior alveolar nerve block (IANB) for testing pulp anesthesia of mandibular first molar teeth in adult volunteers. Materials and Methods: A total of 23 healthy adult volunteers received two regimens with at least 1-week apart; one with 4% articaine buccal infiltration and 2% mepivacaine IANB (articaine regimen) and another with 2% mepivacaine buccal infiltration supplemented to 2% mepivacaine IANB (mepivacaine regimen). Pulp testing of first molar tooth was electronically measured twice at baseline, then at intervals of 2 min for the first 10 min, then every 5 min until 45 min postinjection. Anesthetic success was considered when two consecutive maximal stimulation on pulp testing readings without sensation were obtained within 10 min and continuously sustained for 45 min postinjection. Results: In total, the number of no sensations to maximum pulp testing for first molar teeth were significantly higher after articaine regimen than mepivacaine during 45 min postinjection (267 vs. 250 episodes, respectively, P < 0.001), however, both articaine and mepivacaine buccal infiltrations are equally effective in securing anesthetic success for first molar pulp anesthesia when supplemented to mepivacaine IANB injections (P > 0.05). Interestingly, volunteers in the articaine regimen provided faster onset and longer duration (means 2.78 min, 42.22 min, respectively) than mepivacaine regimen (means 4.26 min, 40.74 min, respectively) for first molar pulp anesthesia (P < 0.001). Conclusions: Supplementary mepivacaine and articaine buccal infiltrations produced similar successful first molar pulp anesthesia following mepivacaine IANB injections in volunteers. Articaine buccal infiltration produced faster onset and

  7. Dental Students’ Preference with Regard to Tactile or Visual Determination of Injection Site for an Inferior Alveolar Nerve Block in Children: A Crossover Randomized Clinical Trial

    PubMed Central

    Iranmanesh, Seyed Masoud

    2016-01-01

    Objectives: Instruction of local anesthesia injection in an important part of dental education curricula. This study was performed to compare dental students’ preference with regard to tactile or visual determination of injection site for an inferior alveolar nerve block (IANB) in children. Materials and Methods: This crossover randomized clinical trial was conducted on dental students of Zahedan Dental School who took the first practical course of pediatric dentistry in the first academic semester of 2013–14 (n=42). They were randomly divided into two groups. During the first phase, group I was instructed to find the needle insertion point for an IANB via tactile method and group II was instructed to do it visually. In the second phase, the groups received instructions for the alternate technique. Both instructions were done using live demonstrations by the same instructor and immediately after instruction the learners practiced an IANB using the taught method. A five-point Likert scale questionnaire was then filled out by the students. The preference score was determined by calculating the mean of item scores. Data were analyzed using Mann-Whitney U and Wilcoxon Singed Rank tests in SPSS 19 at P=0.05 level of significance. Results: Thirty-eight students completed the study. By using the visual method to perform an IANB, students gained a significantly higher mean preference score (P=0.020). There was a significant difference in the preference of male students (P=0.008). Conclusions: Instruction of IANB by visual identification of needle insertion point is more desirable by students. PMID:27536327

  8. An Evaluation of the Effectiveness of Hyaluronidase in the Selective Nerve Root Block of Radiculopathy: A Double Blind, Controlled Clinical Trial

    PubMed Central

    Ko, Sang-Bong; Vaccaro, Alexander R; Shin, Dong-Young

    2015-01-01

    Study Design Prospective, double-blind, randomized controlled trial. Purpose To determine the ability of hyaluronidase to provide longer lasting pain relief and functional improvement in patients with lumbar radiculopathy. Overview of Literature Selective nerve root block (SNRB) is a good treatment option in lumbar radiculopathy. We studied the effectiveness of hyaluronidase when added to the traditional SNRB regimen. Methods A sample size of 126 patients per group was necessary. A sample of 252 patients who underwent an injection procedure with or without hyaluronidase due to radiculopathy was included in this study. The patients were randomly divided into two groups: the control (C) group and the hyaluronidase (H) group. After SNRB due to radiculopathy, the visual analog scale (VAS) was compared at 2, 4, 6, 8, and 12 weeks between the two groups, and the Oswestry disability index (ODI) was compared at 12 weeks between the two groups. Results Both groups seemed to have general improvement in VAS, but in C group, the VAS was higher than the H group 2 and 4 weeks after the surgery, and the difference in time-group change between 2 groups was statistically significant (p <0.05). ODI improved in both groups, and the difference in time-group change between 2 groups was not statistically significant (p >0.05). Conclusions The rebound pain (the re-occurrence of pain within 2-4 weeks after injection) that occurs within 2-4 weeks after the injection of the routine regimen can be reduced when hyaluronidase is added to the routine SNRB regimen. PMID:25705339

  9. A role for midline and intralaminar thalamus in the associative blocking of Pavlovian fear conditioning.

    PubMed

    Sengupta, Auntora; McNally, Gavan P

    2014-01-01

    Fear learning occurs in response to positive prediction error, when the expected outcome of a conditioning trial exceeds that predicted by the conditioned stimuli present. This role for error in Pavlovian association formation is best exemplified by the phenomenon of associative blocking, whereby prior fear conditioning of conditioned stimulus (CS) A is able to prevent learning to CSB when they are conditioned in compound. The midline and intralaminar thalamic nuclei (MIT) are well-placed to contribute to fear prediction error because they receive extensive projections from the midbrain periaqueductal gray-which has a key role in fear prediction error-and project extensively to prefrontal cortex and amygdala. Here we used an associative blocking design to study the role of MIT in fear learning. In Stage I rats were trained to fear CSA via pairings with shock. In Stage II rats received compound fear conditioning of CSAB paired with shock. On test, rats that received Stage I training expressed less fear to CSB relative to control rats that did not receive this training. Microinjection of bupivacaine into MIT prior to Stage II training had no effect on the expression of fear during Stage II and had no effect on fear learning in controls, but prevented associative blocking and so enabled fear learning to CSB. These results show an important role for MIT in predictive fear learning and are discussed with reference to previous findings implicating the midline and posterior intralaminar thalamus in fear learning and fear responding.

  10. The Role of the Vagus Nerve: Modulation of the Inflammatory Reaction in Murine Polymicrobial Sepsis

    PubMed Central

    Kessler, Wolfram; Diedrich, Stephan; Menges, Pia; Ebker, Tobias; Nielson, Michael; Partecke, Lars Ivo; Traeger, Tobias; Cziupka, Katharina; van der Linde, Julia; Puls, Ralf; Busemann, Alexandra; Heidecke, Claus-Dieter; Maier, Stefan

    2012-01-01

    The particular importance of the vagus nerve for the pathophysiology of peritonitis becomes more and more apparent. In this work we provide evidence for the vagal modulation of inflammation in the murine model of colon ascendens stent peritonitis (CASP). Vagotomy significantly increases mortality in polymicrobial sepsis. This effect is not accounted for by the dilatation of gastric volume following vagotomy. As the stimulation of cholinergic receptors by nicotine has no therapeutic effect, the lack of nicotine is also not the reason for the reduced survival rate. In fact, increased septic mortality is a consequence of the absent modulating influence of the vagus nerve on the immune system: we detected significantly elevated serum corticosterone levels in vagotomised mice 24 h following CASP and a decreased ex vivo TNF-alpha secretion of Kupffer cells upon stimulation with LPS. In conclusion, the vagus nerve has a modulating influence in polymicrobial sepsis by attenuating the immune dysregulation. PMID:22547905

  11. Role of Sonography in Surgical Decision Making for Iatrogenic Spinal Accessory Nerve Injuries: A Paradigm Shift.

    PubMed

    Cesmebasi, Alper; Smith, Jay; Spinner, Robert J

    2015-12-01

    The spinal accessory nerve (SAN) is susceptible to iatrogenic injury in the posterior cervical triangle. Early diagnosis and management of suspected SAN transection injuries are crucial in the restoration of shoulder stability and function. Although neurologic examination and electrodiagnostic testing can assess SAN function, they cannot assess nerve continuity. We report the use of sonography to prospectively evaluate the SAN in 6 patients with suspected iatrogenic SAN injury. Sonography directly visualized SAN transection in 4 cases, whereas sonographic findings were reported as "probable" transection in the fifth case and was nondiagnostic in the sixth case in the setting of extensive scarring. PMID:26543166

  12. Role of thermography in the assessment of infraorbital nerve injury after malar fractures.

    PubMed

    McGimpsey, J G; Vaidya, A; Biagioni, P A; Lamey, P J

    2000-12-01

    We studied 45 patients with malar fractures who had some degree of infraorbital nerve deficit. Thermographic facial images failed to show any substantial changes in the temperature profiles of the affected and the normal control sides in relation to reco very of their facial sensation. Although some patients who had thermography on the day of injury showed significant temperature differences between the affected and the normal sides, these differences were probably the result of the acute inflammatory ch anges caused by the injury. We suggest that infrared thermography has little place in the assessment of infraorbital nerve deficits. PMID:11092769

  13. The role of analgesic blocking in the management of cancer pain: current trends. a review article.

    PubMed

    Lund, P C

    1982-01-01

    The significant role of reversible and neurolytic analgesic blocking in the management of cancer pain in general is presented. It is pointed out that this modality of therapy may play a very significant role in the management of many such patients. It is pointed out that blocks of the peripheral as well as the central nervous system should be considered early rather than late in these disease syndromes in order to prevent central fixation. It is obvious that these procedures should be employed much more extensively than is generally the case at the present time. The opinions expressed are based upon over 30 years of clinical experience and a review of the current literature dealing with the management of pain. PMID:6960118

  14. Purinergic nerves and receptors.

    PubMed

    Burnstock, G

    1980-01-01

    The presence of a non-cholinergic, non-adrenergic component in the vertebrate autonomic nervous system is now well established. Evidence that ATP is the transmitter released from some of these nerves (called "purinergic') includes: (a) synthesis and storage of ATP in nerves: (b) release of ATP from the nerves when they are stimulated; (c) exogenously applied ATP mimicking the action of nerve-released transmitter; (d) the presence of ectoenzymes which inactivate ATP; (e) drugs which produce similar blocking or potentiating effects on the response to exogenously applied ATP and nerve stimulation. A basis for distinguishing two types of purinergic receptors has been proposed according to four criteria: relative potencies of agonists, competitive antagonists, changes in levels of cAMP and induction of prostaglandin synthesis. Thus P1 purinoceptors are most sensitive to adenosine, are competitively blocked by methylxanthines and their occupation leads to changes in cAMP accumulation; while P2 purinoceptors are most sensitive to ATP, are blocked (although not competitively) by quinidine, 2-substituted imidazolines, 2,2'-pyridylisatogen and apamin, and their occupation leads to production of prostaglandin. P2 purinoceptors mediate responses of smooth muscle to ATP released from purinergic nerves, while P1 purinoceptors mediate the presynaptic actions of adenosine on adrenergic, cholinergic and purinergic nerve terminals. PMID:6108568

  15. The role of neuregulin-1 in the response to nerve injury

    PubMed Central

    Fricker, Florence R; Bennett, David LH

    2011-01-01

    Axons and Schwann cells exist in a highly interdependent relationship: damage to one cell type invariably leads to pathophysiological changes in the other. Greater understanding of communication between these cell types will not only give insight into peripheral nerve development, but also the reaction to and recovery from peripheral nerve injury. The type III isoform of neuregulin-1 (NRG1) has emerged as a key signaling factor that is expressed on axons and, through binding to erbB2/3 receptors on Schwann cells, regulates multiple phases of their development. In adulthood, NRG1 is dispensable for the maintenance of the myelin sheath; however, this factor is required for both axon regeneration and remyelination following nerve injury. The outcome of NRG1 signaling depends on interactions with other pathways within Schwann cells such as Notch, integrin and cAMP signaling. In certain circumstances, this signaling pathway may be maladaptive; for instance, direct binding of Mycobacterium leprae onto erbB2 receptors produces excessive activation and can actually promote demyelination. Attempts to modulate this pathway in order to promote nerve repair will therefore need to give consideration to the exact isoform used, as well as how it is processed and the context in which it is presented to the Schwann cell. PMID:22121335

  16. Opposing roles of smooth muscle BK channels and ryanodine receptors in the regulation of nerve-evoked constriction of mesenteric resistance arteries.

    PubMed

    Krishnamoorthy, Gayathri; Sonkusare, Swapnil K; Heppner, Thomas J; Nelson, Mark T

    2014-04-01

    In depolarized smooth muscle cells of pressurized cerebral arteries, ryanodine receptors (RyRs) generate "Ca2+ sparks" that activate large-conductance, Ca2+ -, and voltage-sensitive potassium (BK) channels to oppose pressure-induced (myogenic) constriction. Here, we show that BK channels and RyRs have opposing roles in the regulation of arterial tone in response to sympathetic nerve activation by electrical field stimulation. Inhibition of BK channels with paxilline increased both myogenic and nerve-induced constrictions of pressurized, resistance-sized mesenteric arteries from mice. Inhibition of RyRs with ryanodine increased myogenic constriction, but it decreased nerve-evoked constriction along with a reduction in the amplitude of nerve-evoked increases in global intracellular Ca2+. In the presence of L-type voltage-dependent Ca2+ channel (VDCC) antagonists, nerve stimulation failed to evoke a change in arterial diameter, and BK channel and RyR inhibitors were without effect, suggesting that nerve- induced constriction is dependent on activation of VDCCs. Collectively, these results indicate that BK channels and RyRs have different roles in the regulation of myogenic versus neurogenic tone: whereas BK channels and RyRs act in concert to oppose myogenic vasoconstriction, BK channels oppose neurogenic vasoconstriction and RyRs augment it. A scheme for neurogenic vasoregulation is proposed in which RyRs act in conjunction with VDCCs to regulate nerve-evoked constriction in mesenteric resistance arteries.

  17. Chemical Interactions and Their Role in the Microphase Separation of Block Copolymer Thin Films

    PubMed Central

    Farrell, Richard A.; Fitzgerald, Thomas G.; Borah, Dipu; Holmes, Justin D.; Morris, Michael A.

    2009-01-01

    The thermodynamics of self-assembling systems are discussed in terms of the chemical interactions and the intermolecular forces between species. It is clear that there are both theoretical and practical limitations on the dimensions and the structural regularity of these systems. These considerations are made with reference to the microphase separation that occurs in block copolymer (BCP) systems. BCP systems self-assemble via a thermodynamic driven process where chemical dis-affinity between the blocks driving them part is balanced by a restorative force deriving from the chemical bond between the blocks. These systems are attracting much interest because of their possible role in nanoelectronic fabrication. This form of self-assembly can obtain highly regular nanopatterns in certain circumstances where the orientation and alignment of chemically distinct blocks can be guided through molecular interactions between the polymer and the surrounding interfaces. However, for this to be possible, great care must be taken to properly engineer the interactions between the surfaces and the polymer blocks. The optimum methods of structure directing are chemical pre-patterning (defining regions on the substrate of different chemistry) and graphoepitaxy (topographical alignment) but both centre on generating alignment through favourable chemical interactions. As in all self-assembling systems, the problems of defect formation must be considered and the origin of defects in these systems is explored. It is argued that in these nanostructures equilibrium defects are relatively few and largely originate from kinetic effects arising during film growth. Many defects also arise from the confinement of the systems when they are ‘directed’ by topography. The potential applications of these materials in electronics are discussed. PMID:19865513

  18. A clinician's perspective of the role of renal sympathetic nerves in hypertension

    PubMed Central

    Briasoulis, Alexandros; Bakris, George L.

    2015-01-01

    The renal sympathetic nerves have significant contribution to the control of different aspects of kidney function. Early animal studies of renal denervation in a large number of different models of hypertension showed that that RDN improved BP control. Recently, data from prospective cohorts and randomized studies showed that renal denervation therapy (RDN) is a safe procedure but is associated with only modest reduction of ambulatory blood pressure (BP) in patients on intensive medical therapy. The main goal of this article is to review the results of preclinical and clinical studies on the contribution of the renal sympathetic nervous system to hypertension and the therapeutic applications of catheter-based renal denervation. PMID:25859218

  19. The role of cyclic nucleotides in modulation of the membrane potential of the Schwann cell of squid giant nerve fibre.

    PubMed Central

    Evans, P D; Reale, V; Villegas, J

    1985-01-01

    The role of cyclic nucleotides in mediating the effects of nicotine cholinergic receptors has been investigated in Schwann cells of the giant nerve fibre of the squid. Elevation of cyclic AMP levels in this preparation by means of the phosphodiesterase inhibitor, theophylline, by the diterpene adenylate cyclase activator, forskolin, and by cyclic nucleotide analogues mimics the action of activating the nicotinic cholinergic receptors in producing a long-lasting hyperpolarization of the membrane potential of the Schwann cell. Theophylline and forskolin also potentiate the effects of carbachol and of neural stimulation on the Schwann cell. The results suggest that the nicotinic receptor of the squid Schwann cell is likely to mediate its effects via a mechanism that activates adenylate cyclase. The results are discussed in terms of the role of cyclic AMP in the complex multistep interaction between the giant axon of the squid and its surrounding Schwann-cell layer. PMID:2991504

  20. The role of cyclic nucleotides in modulation of the membrane potential of the Schwann cell of squid giant nerve fibre.

    PubMed

    Evans, P D; Reale, V; Villegas, J

    1985-06-01

    The role of cyclic nucleotides in mediating the effects of nicotine cholinergic receptors has been investigated in Schwann cells of the giant nerve fibre of the squid. Elevation of cyclic AMP levels in this preparation by means of the phosphodiesterase inhibitor, theophylline, by the diterpene adenylate cyclase activator, forskolin, and by cyclic nucleotide analogues mimics the action of activating the nicotinic cholinergic receptors in producing a long-lasting hyperpolarization of the membrane potential of the Schwann cell. Theophylline and forskolin also potentiate the effects of carbachol and of neural stimulation on the Schwann cell. The results suggest that the nicotinic receptor of the squid Schwann cell is likely to mediate its effects via a mechanism that activates adenylate cyclase. The results are discussed in terms of the role of cyclic AMP in the complex multistep interaction between the giant axon of the squid and its surrounding Schwann-cell layer.

  1. The role of astrocytes in optic nerve head fibrosis in glaucoma.

    PubMed

    Schneider, Magdalena; Fuchshofer, Rudolf

    2016-01-01

    Glaucoma is defined as a progressive optic neuropathy and is characterized by an irreversible loss of retinal ganglion cells. The main risk factor to develop glaucoma is an increased intraocular pressure (IOP). During the course of glaucoma structural changes in the optic nerve head (ONH) take place which lead to the characteristic excavation or cupping of the ONH. In this review we will focus on mechanisms and processes involved in structural alterations of the extracellular matrix in the lamina cribrosa (LC) of the ONH, which are associated with astrocytes. In glaucoma, a disordered deposition of elastic and collagen fibers and a typical pronounced thickening of the connective tissue septae surrounding the nerve fibers can be observed in the LC region. The remodeling process of the LC and the loss of ON axons are associated with a conversion of astrocytes from quiescent to a reactivated state. The extracellular matrix changes in the LC are thought to be due to a disturbed homeostatic balance of growth factors and the reactivated astrocytes are part of this process. Reactivated astrocytes, remodeling of the ECM within the LC and an elevated IOP are taking part in the retinal ganglion cell loss in glaucoma.

  2. The role of intercostal nerve preservation in acute pain control after thoracotomy*

    PubMed Central

    Marchetti-Filho, Marco Aurélio; Leão, Luiz Eduardo Villaça; Costa-Junior, Altair da Silva

    2014-01-01

    OBJECTIVE: To evaluate whether the acute pain experienced during in-hospital recovery from thoracotomy can be effectively reduced by the use of intraoperative measures (dissection of the neurovascular bundle prior to the positioning of the Finochietto retractor and preservation of the intercostal nerve during closure). METHODS: We selected 40 patients who were candidates for elective thoracotomy in the Thoracic Surgery Department of the Federal University of São Paulo/Paulista School of Medicine, in the city of São Paulo, Brazil. The patients were randomized into two groups: conventional thoracotomy (CT, n = 20) and neurovascular bundle preservation (NBP, n = 20). All of the patients underwent thoracic epidural anesthesia and muscle-sparing thoracotomy. Pain intensity was assessed with a visual analog scale on postoperative days 1, 3, and 5, as well as by monitoring patient requests for/consumption of analgesics. RESULTS: On postoperative day 5, the self-reported pain intensity was significantly lower in the NBP group than in the CT group (visual analog scale score, 1.50 vs. 3.29; p = 0.04). No significant differences were found between the groups regarding the number of requests for/consumption of analgesics. CONCLUSIONS: In patients undergoing thoracotomy, protecting the neurovascular bundle prior to positioning the retractor and preserving the intercostal nerve during closure can minimize pain during in-hospital recovery. PMID:24831401

  3. The role of astrocytes in optic nerve head fibrosis in glaucoma.

    PubMed

    Schneider, Magdalena; Fuchshofer, Rudolf

    2016-01-01

    Glaucoma is defined as a progressive optic neuropathy and is characterized by an irreversible loss of retinal ganglion cells. The main risk factor to develop glaucoma is an increased intraocular pressure (IOP). During the course of glaucoma structural changes in the optic nerve head (ONH) take place which lead to the characteristic excavation or cupping of the ONH. In this review we will focus on mechanisms and processes involved in structural alterations of the extracellular matrix in the lamina cribrosa (LC) of the ONH, which are associated with astrocytes. In glaucoma, a disordered deposition of elastic and collagen fibers and a typical pronounced thickening of the connective tissue septae surrounding the nerve fibers can be observed in the LC region. The remodeling process of the LC and the loss of ON axons are associated with a conversion of astrocytes from quiescent to a reactivated state. The extracellular matrix changes in the LC are thought to be due to a disturbed homeostatic balance of growth factors and the reactivated astrocytes are part of this process. Reactivated astrocytes, remodeling of the ECM within the LC and an elevated IOP are taking part in the retinal ganglion cell loss in glaucoma. PMID:26321510

  4. Role of the renal sympathetic nerves in renal sodium/potassium handling and renal damage in spontaneously hypertensive rats

    PubMed Central

    Li, Jianling; He, Qiaoling; Wu, Weifeng; Li, Qingjie; Huang, Rongjie; Pan, Xiaofeng; Lai, Wenying

    2016-01-01

    Renal sympathetic nerve activity has an important role in renal disease-associated hypertension and in the modulation of fluid homeostasis. In the present study, changes in renal function and renal sodium/potassium handling were investigated in groups of 12-week-old male, spontaneously hypertensive rats with renal denervation (RDNX group) or sham denervation (sham group). The RDNX group excreted significantly more sodium than the sham group during the 2-week observation period (P<0.05). Following bilateral renal denervation, the fractional lithium excretion was elevated in the RDNX group compared with the sham group, but no significant effect was observed of renal denervation on the fractional distal reabsorption rate of sodium or the fractional excretion of potassium. Furthermore, the glomerular injury score and the wall-to-lumen ratio of the interlobular artery were significantly lower in the RDNX group than in the sham group (P<0.05). In conclusion, the present study indicates an involvement of the renal sympathetic nerves in the regulation of renal tubular sodium reabsorption in spontaneously hypertensive rats and in the renal damage associated with hypertension. PMID:27698757

  5. Role of the renal sympathetic nerves in renal sodium/potassium handling and renal damage in spontaneously hypertensive rats

    PubMed Central

    Li, Jianling; He, Qiaoling; Wu, Weifeng; Li, Qingjie; Huang, Rongjie; Pan, Xiaofeng; Lai, Wenying

    2016-01-01

    Renal sympathetic nerve activity has an important role in renal disease-associated hypertension and in the modulation of fluid homeostasis. In the present study, changes in renal function and renal sodium/potassium handling were investigated in groups of 12-week-old male, spontaneously hypertensive rats with renal denervation (RDNX group) or sham denervation (sham group). The RDNX group excreted significantly more sodium than the sham group during the 2-week observation period (P<0.05). Following bilateral renal denervation, the fractional lithium excretion was elevated in the RDNX group compared with the sham group, but no significant effect was observed of renal denervation on the fractional distal reabsorption rate of sodium or the fractional excretion of potassium. Furthermore, the glomerular injury score and the wall-to-lumen ratio of the interlobular artery were significantly lower in the RDNX group than in the sham group (P<0.05). In conclusion, the present study indicates an involvement of the renal sympathetic nerves in the regulation of renal tubular sodium reabsorption in spontaneously hypertensive rats and in the renal damage associated with hypertension.

  6. Surgery for traumatic facial nerve paralysis: does intraoperative monitoring have a role?

    PubMed

    Ashram, Yasmine A; Badr-El-Dine, Mohamed M K

    2014-09-01

    The use of intraoperative facial nerve (FN) monitoring during surgical decompression of the FN is underscored because surgery is indicated when the FN shows more than 90 % axonal degeneration. The present study proposes including intraoperative monitoring to facilitate decision taking and provide prognostication with more accuracy. This prospective study was conducted on ten patients presenting with complete FN paralysis due to temporal bone fracture. They were referred after variable time intervals for FN exploration and decompression. Intraoperative supramaximal electric stimulation (2-3 mA) of the FN was attempted in all patients both proximal and distal to the site of injury. Postoperative FN function was assessed using House-Brackmann (HB) scale. All patients had follow-up period ranging from 7 to 42 months. Three different patterns of neurophysiological responses were characterized. Responses were recorded proximal and distal to the lesion in five patients (pattern 1); only distal to the lesion in two patients (pattern 2); and neither proximal nor distal to the lesion in three patients (pattern 3). Sporadic, mechanically elicited EMG activity was recorded in eight out of ten patients. Patients with pattern 1 had favorable prognosis with postoperative function ranging between grade I and III. Pattern 3 patients showing no mechanically elicited activity had poor prognosis. Intraoperative monitoring affects decision taking during surgery for traumatic FN paralysis and provides prognostication with sufficient accuracy. The detection of mechanically elicited EMG activity is an additional sign predicting favorable outcome. However, absence of responses did not alter surgeon decision when the nerve was found evidently intact.

  7. Regulation of the expression of peripheral benzodiazepine receptors and their endogenous ligands during rat sciatic nerve degeneration and regeneration: a role for PBR in neurosteroidogenesis.

    PubMed

    Lacor, P; Gandolfo, P; Tonon, M C; Brault, E; Dalibert, I; Schumacher, M; Benavides, J; Ferzaz, B

    1999-01-01

    Peripheral benzodiazepine receptors (PBR) and their endogenous ligands, the diazepam-binding inhibitor derived-peptides, are present in Schwann cells in the peripheral nervous system. The aim of this study was to determine the influence of reversible (freeze-injury) and permanent (transection and ligature) nerve lesion on PBR density and on the levels of their endogenous ligands, by autoradiography (using [3H]PK11195) and radioimmunoassay (using antisera directed against the octadecaneuropeptide (ODN), a diazepam-binding inhibitor fragment). The potential role of PBR on peripheral nerve steroidogenesis, was studied by investigating the effect of specific PBR agonists and antagonists on pregnenolone levels in the sciatic nerve. Sixteen to 30 days after nerve lesion, PBR density and ODN-LI level were highly increased. Their expression returned to normal level when regeneration was completed 60 days after freeze-injury, but remained elevated when regeneration did not occur in transected distal stumps. Reverse-phase HPLC analysis of ODN-LI showed that in control nerve extracts, the major immunoreactive peak co-elutes with triakontatetraneuropeptide (TTN). After freeze-injury, intermediate molecular forms eluting between ODN and TTN were predominant and remained elevated at day 60. The greater accumulation of intermediate forms when regeneration is allowed to occur may indicate a particular role of these forms in axonal elongation and myelination. Ro5-4864, a high affinity PBR agonist increased pregnenolone concentration in the sciatic nerve. This effect was antagonised by PK11195, a high affinity PBR antagonist, which had no effect on pregnenolone basal level, indicating a specific action of PBR in neurosteroid production. These results suggest a role for PBR and their endogenous ligands in peripheral nerve regeneration. A trophic effect could be exerted via stimulation of steroid synthesis.

  8. The role of adenosine A2A and A3 receptors on the differential modulation of norepinephrine and neuropeptide Y release from peripheral sympathetic nerve terminals.

    PubMed

    Donoso, M Verónica; Aedo, Felipe; Huidobro-Toro, J Pablo

    2006-03-01

    The pre-synaptic sympathetic modulator role of adenosine was assessed by studying transmitter release following electrical depolarization of nerve endings from the rat mesenteric artery. Mesentery perfusion with exogenous adenosine exclusively inhibited the release of norepinephrine (NA) but did not affect the overflow of neuropeptide Y (NPY), establishing the basis for a differential pre-synaptic modulator mechanism. Several adenosine structural analogs mimicked adenosine's effect on NA release and their relative order of potency was: 2-p-(2-carboxyethyl)phenethylamino-5'-N-ethylcarboxamidoadenosine hydrochloride = 1-[2-chloro-6-[[(3-iodophenyl)methyl]amino]-9H-purin-9-yl]-1-deoxy-N-methyl-beta-d-ribofuranuronamide = 5'-(N-ethylcarboxamido)adenosine > adenosine > N(6)-cyclopentyladenosine. The use of selective receptor subtype antagonists confirmed the involvement of A(2A) and A(3) adenosine receptors. The modulator role of adenosine is probably due to the activation of both receptors; co-application of 1 nM 2-p-(2-carboxyethyl)phenethylamino-5'-N-ethylcarboxamidoadenosine hydrochloride plus 1 nM 1-[2-chloro-6-[[(3-iodophenyl)methyl]amino]-9H-purin-9-yl]-1-deoxy-N-methyl-beta-D-ribofuranuronamide caused additive reductions in NA released. Furthermore, while 1 nM of an A(2A) or A(3) receptor antagonist only partially reduced the inhibitory action of adenosine, the combined co-application of the two antagonists fully blocked the adenosine-induced inhibition. Only the simultaneous blockade of the adenosine A(2A) plus A(3) receptors with selective antagonists elicited a significant increase in NA overflow. H 89 reduced the release of both NA and NPY. We conclude that pre-synaptic A(2A) and A(3) adenosine receptor activation modulates sympathetic co-transmission by exclusively inhibiting the release of NA without affecting immunoreactive (ir)-NPY and we suggest separate mechanisms for vesicular release modulation.

  9. Differential role of entorhinal and hippocampal nerve growth factor in short- and long-term memory modulation.

    PubMed

    Walz, R; Roesler, R; Reinke, A; Martins, M R; Quevedo, J; Izquierdo, I

    2005-01-01

    We studied the effects of infusion of nerve growth factor (NGF) into the hippocampus and entorhinal cortex of male Wistar rats (250-300 g, N = 11-13 per group) on inhibitory avoidance retention. In order to evaluate the modulation of entorhinal and hippocampal NGF in short- and long-term memory, animals were implanted with cannulae in the CA1 area of the dorsal hippocampus or entorhinal cortex and trained in one-trial step-down inhibitory avoidance (foot shock, 0.4 mA). Retention tests were carried out 1.5 h or 24 h after training to measure short- and long-term memory, respectively. Immediately after training, rats received 5 microl NGF (0.05, 0.5 or 5.0 ng) or saline per side into the CA1 area and entorhinal cortex. The correct position of the cannulae was confirmed by histological analysis. The highest dose of NGF (5.0 ng) into the hippocampus blocked short-term memory (P < 0.05), whereas the doses of 0.5 (P < 0.05) and 5.0 ng (P < 0.01) NGF enhanced long-term memory. NGF administration into the entorhinal cortex improved long-term memory at the dose of 5.0 ng (P < 0.05) and did not alter short-term memory. Taken as a whole, our results suggest a differential modulation by entorhinal and hippocampal NGF of short- and long-term memory.

  10. The role of calcium in depolarization-secretion coupling at the motor nerve terminal.

    PubMed

    Cooke, J D; Okamoto, K; Quastel, D M

    1973-01-01

    1. The relation between m.e.p.p. frequency (F) and [Ca] was studied at the mouse neuromuscular junction, at varied concentrations of K(+) and at nerve terminals depolarized by focal depolarization.2. Under all conditions the relation between log F and log [Ca] was sigmoid, with a maximum slope that increased with depolarization or raised [K(+)]. In addition, depolarization or raised K(+) caused a progressive shift of the sigmoid curve upward and to the left (to reduced log [Ca]) and increased the range over which log F could be altered by [Ca].3. Reduction of osmotic pressure changed the relation between log F and log [Ca] in the same way as increase of depolarization, while increase of osmotic pressure did the opposite.4. Raised [Mg] acted in two ways: (a) to shift the curve of log F vs. log [Ca] to the right and (b) to reduce maximum Delta log F/Delta log [Ca] without altering the range of log F sensitive to [Ca].5. The relation between log quantal content of e.p.p.s and log [Ca] was similar to that between log m.e.p.p. frequency and log [Ca].6. Individual nerve terminals varied in both Ca-dependent and Ca-independent fractions of log F; a large Ca-independent portion appears to be associated with a low Ca-dependent portion and vice versa. With large prolonged depolarization the Ca-independent portion was increased, apparently at the expense of the Ca-dependent portion.7. The results of all experiments were summarized in terms of parameters found by fitting the observed log release -log [Ca] curves to two theoretical equations, each derived on the basis of a model: (a) all-or-nothing activation of release probability by Ca-complex(es) and (b) graded activation of release probability by Ca complex(es).8. On the basis of the all-or-nothing model, from which follows alinear relation between F and amounts of Ca complex(es), the number of Ca(2+) atoms that ;cooperate' to mediate release appeared to increase progressively with presynaptic depolarization, to a value of

  11. Graves' Disease Mechanisms: The Role of Stimulating, Blocking, and Cleavage Region TSH Receptor Antibodies

    PubMed Central

    Morshed, S. A.; Davies, T. F.

    2016-01-01

    The immunologic processes involved in Graves' disease (GD) have one unique characteristic – the autoantibodies to the TSH receptor (TSHR) – which have both linear and conformational epitopes. Three types of TSHR antibodies (stimulating, blocking, and cleavage) with different functional capabilities have been described in GD patients, which induce different signaling effects varying from thyroid cell proliferation to thyroid cell death. The establishment of animal models of GD by TSHR antibody transfer or by immunization with TSHR antigen has confirmed its pathogenic role and, therefore, GD is the result of a breakdown in TSHR tolerance. Here we review some of the characteristics of TSHR antibodies with a special emphasis on new developments in our understanding of what were previously called “neutral” antibodies and which we now characterize as autoantibodies to the “cleavage” region of the TSHR ectodomain. PMID:26361259

  12. Critical role of PTEN for development and progression of nerve sheath tumors in neurofibromatosis type 1.

    PubMed

    Mawrin, Christian

    2010-04-01

    Evaluation of: Gregorian C, Nakashima J, Dry SM et al.: PTEN dosage is essential for neurofibroma development and malignant transformation. Proc. Natl Acad. Sci. USA 106(46), 19479-19484 (2009). Neurofibromatosis type 1 (NF1) is among the most common inherited tumor-predisposing syndromes in humans. Development of malignant peripheral nerve sheath tumors (MPNSTs) from neurofibroma significantly affects the morbidity and mortality of NF1 patients. The authors demonstrate, using different genetically engineered mouse models, that loss of the tumor suppressor Pten in combination with overexpression of the K-ras oncogene is an important step in MPNST development. In both mouse and human tumors, the transition from low-grade neurofibromas to MPNST is associated with reduced Pten expression, deregulated mTOR signaling activity and increased proliferation. This tumor transition can be monitored by (18)F-fluoro-D-glucose-PET, offering close clinical monitoring of NF1 patients and thus early detection of MPNST development in the future. PMID:20373864

  13. Critical role of PTEN for development and progression of nerve sheath tumors in neurofibromatosis type 1.

    PubMed

    Mawrin, Christian

    2010-04-01

    Evaluation of: Gregorian C, Nakashima J, Dry SM et al.: PTEN dosage is essential for neurofibroma development and malignant transformation. Proc. Natl Acad. Sci. USA 106(46), 19479-19484 (2009). Neurofibromatosis type 1 (NF1) is among the most common inherited tumor-predisposing syndromes in humans. Development of malignant peripheral nerve sheath tumors (MPNSTs) from neurofibroma significantly affects the morbidity and mortality of NF1 patients. The authors demonstrate, using different genetically engineered mouse models, that loss of the tumor suppressor Pten in combination with overexpression of the K-ras oncogene is an important step in MPNST development. In both mouse and human tumors, the transition from low-grade neurofibromas to MPNST is associated with reduced Pten expression, deregulated mTOR signaling activity and increased proliferation. This tumor transition can be monitored by (18)F-fluoro-D-glucose-PET, offering close clinical monitoring of NF1 patients and thus early detection of MPNST development in the future.

  14. Role of potassium channels in the nitrergic nerve stimulation-induced vasodilatation in the guinea-pig isolated basilar artery

    PubMed Central

    Jiang, Fan; Li, Chun Guang; Rand, Michael J

    1998-01-01

    We studied the effects of various K+ channel blockers on the vasodilator responses of guinea-pig isolated basilar arteries to nitrergic nerve stimulation, the nitric oxide (NO) donor sodium nitroprusside (SNP), and the membrane permeable guanosine-3′, 5′-cyclic monophosphate (cyclic GMP) analogue 8-bromo-cyclic GMP (8-Br-cyclic GMP).In endothelium-denuded preparations which were contracted with prostaglandin F2α (1 μM), electrical field stimulation (EFS, 10 Hz for 30 s) produced a vasodilatation which was totally blocked by the nitric oxide synthase (NOS) inhibitor NG-nitro-L-arginine methyl ester L-NAME; 100 μM) (n=3) and by the selective NO-sensitive guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one (ODQ; 1 μM) (n=4). The vasodilator response to SNP (100 nM) was not reduced by L-NAME but was abolished by ODQ (1 μM) (n=4).EFS-elicited vasodilatation was partly but significantly reduced by the non-selective K+ channel blockers tetraethylammonium (TEA, 1 and 3 mM) and 4-aminopyridine (4-AP, 3 mM), and by the large-conductance calcium-activated K+ channel (KCa channel) blockers charybdotoxin (ChTX, 150 nM) and iberiotoxin (IbTX, 30 and 100 nM). In contrast, the ATP-sensitive K+ channel (KATP channel) blocker glibenclamide (1–10 μM) and the small-conductance KCa channel blocker apamin (100–500 nM) did not affect EFS-induced vasodilatation.The vasodilator response elicited by SNP (10–100 nM) was significantly reduced by TEA (3 mM) and ChTX (150 nM) but not by apamin (500 nM) or glibenclamide (1 μM). The vasodilatation elicited by 8-Br-cyclic GMP (100 μM) was also reduced by TEA (3 mM) and ChTX (150 nM).The results indicate that the vasodilatations induced by nitrergic nerve stimulation and the NO donor SNP in endothelium-denuded guinea-pig basilar artery depend on the formation of intracellular cyclic GMP. The increased cyclic GMP level activates large-conductance KCa channels which

  15. Nerve biopsy

    MedlinePlus

    ... Loss of axon tissue Metabolic neuropathies Necrotizing vasculitis Sarcoidosis Risks Allergic reaction to the local anesthetic Discomfort ... Neurosarcoidosis Peripheral neuropathy Primary amyloidosis Radial nerve dysfunction Sarcoidosis Tibial nerve dysfunction Update Date 6/1/2015 ...

  16. Role of endothelin-1 in mediating changes in cardiac sympathetic nerve activity in heart failure.

    PubMed

    Abukar, Yonis; May, Clive N; Ramchandra, Rohit

    2016-01-01

    Heart failure (HF) is associated with increased sympathetic nerve activity to the heart (CSNA), which is directly linked to mortality in HF patients. Previous studies indicate that HF is associated with high levels of plasma endothelin-1 (ET-1), which correlates with the severity of the disease. We hypothesized that blockade of endothelin receptors would decrease CSNA. The effects of intravenous tezosentan (a nonselective ETA and ETB receptor antagonist) (8 mg·kg(-1)·h(-1)) on resting levels of CSNA, arterial pressure, and heart rate were determined in conscious normal sheep (n = 6) and sheep with pacing-induced HF (n = 7). HF was associated with a significant decrease in ejection fraction (from 74 ± 2% to 38 ± 1%, P < 0.001) and a significant increase in resting levels of CSNA burst incidence (from 56 ± 11 to 87 ± 2 bursts/100 heartbeats, P < 0.01). Infusion of tezosentan for 60 min significantly decreased resting mean aterial pressure (MAP) in both normal and HF sheep (-8 ± 4 mmHg and -4 ± 3 mmHg, respectively; P < 0.05). This was associated with a significant decrease in CSNA (by 25 ± 26% of control) in normal sheep, but there was no change in CSNA in HF sheep. Calculation of spontaneous baroreflex gain indicated significant impairment of the baroreflex control of HR after intravenous tezosentan infusion in normal animals but no change in HF animals. These data suggest that endogenous levels of ET-1 contribute to the baseline levels of CSNA in normal animals, but this effect is absent in HF.

  17. Role of endothelin-1 in mediating changes in cardiac sympathetic nerve activity in heart failure.

    PubMed

    Abukar, Yonis; May, Clive N; Ramchandra, Rohit

    2016-01-01

    Heart failure (HF) is associated with increased sympathetic nerve activity to the heart (CSNA), which is directly linked to mortality in HF patients. Previous studies indicate that HF is associated with high levels of plasma endothelin-1 (ET-1), which correlates with the severity of the disease. We hypothesized that blockade of endothelin receptors would decrease CSNA. The effects of intravenous tezosentan (a nonselective ETA and ETB receptor antagonist) (8 mg·kg(-1)·h(-1)) on resting levels of CSNA, arterial pressure, and heart rate were determined in conscious normal sheep (n = 6) and sheep with pacing-induced HF (n = 7). HF was associated with a significant decrease in ejection fraction (from 74 ± 2% to 38 ± 1%, P < 0.001) and a significant increase in resting levels of CSNA burst incidence (from 56 ± 11 to 87 ± 2 bursts/100 heartbeats, P < 0.01). Infusion of tezosentan for 60 min significantly decreased resting mean aterial pressure (MAP) in both normal and HF sheep (-8 ± 4 mmHg and -4 ± 3 mmHg, respectively; P < 0.05). This was associated with a significant decrease in CSNA (by 25 ± 26% of control) in normal sheep, but there was no change in CSNA in HF sheep. Calculation of spontaneous baroreflex gain indicated significant impairment of the baroreflex control of HR after intravenous tezosentan infusion in normal animals but no change in HF animals. These data suggest that endogenous levels of ET-1 contribute to the baseline levels of CSNA in normal animals, but this effect is absent in HF. PMID:26468257

  18. Role of cardiotoxin and phospholipase A in the blockade of nerve conduction and depolarization of skeletal muscle induced by cobra venom

    PubMed Central

    Chang, C. C.; Chuang, Sing-Tai; Lee, C. Y.; Wei, J. W.

    1972-01-01

    1. The effects of phospholipase A (PhA), cardiotoxin (CTX) and neurotoxin (cobrotoxin) isolated from Formosan cobra (Naja naja atra) venom on conduction of the rat phrenic nerve and membrane potential of the rat diaphragm were studied. 2. Phospholipase A, lysolecithin and cobrotoxin were without effect on the axonal conduction. Cardiotoxin was the only active agent in cobra venom, but it was less potent than the crude venom. 3. The blocking action of cardiotoxin was markedly accelerated by the simultaneous administration of phospholipase A. However, the minimum effective concentration of cardiotoxin (100 μg/ml), was not decreased by phospholipase A. Pretreatment of the nerve with phospholipase A, followed by washout, did not alter the activity of cardiotoxin. 4. Cardiotoxin (3 μg/ml) completely depolarized the membrane of superficial muscle fibres within 60 min, being 3 times more potent than the crude venom. Phospholipase A, on the other hand, needed a dose 30 times higher and a prolonged period of incubation to induce depolarization of similar extent. Cobrotoxin was without effect on membrane potentials. 5. CaCl2 (10 mM) effectively antagonized the nerve blocking as well as the depolarizing effect of the crude venom, cardiotoxin or cardiotoxin plus phospholipase A. By contrast, the slow depolarizing effect of phospholipase A was enhanced by high concentrations of calcium. 6. Cardiotoxic fractions of Indian cobra venom affected both nerve conduction and diaphragm membrane potential in exactly the same way as cardiotoxin. Toxin A of the same venom was without effect. 7. It is concluded that the active agent in cobra venoms either on axonal conduction or on muscle membrane is cardiotoxin. The synergistic effect of phospholipase A on cardiotoxin appears to be due to acceleration rather than potentiation of its action. The mechanism of action of cardiotoxin and its synergism by phospholipase A are discussed. PMID:5041453

  19. Can low dose spinal anesthesia combined with ultrasound guided bilateral ilioinguinal-iliohypogastric nerve blocks avoid use of additional epidural catheter in high risk obstetric cases? Our experience from two cases.

    PubMed

    Bhakta, P; Sharma, P K; Date, R R; Mohammad, A K

    2013-01-01

    Critical obstetric cases associated with cardiac pathology may pose real challenge for anaesthesiologist during Caesarean section. Meticulous perioperative care and suitable selection of anaesthesia technique are the key to successful outcome. Single shot spinal anaesthesia is not used any more because of serious haemodynamic consequence. Progressive and controlled epidural local anaesthetic injection is mostly used in such cases. But recently combined spinal epidural anaesthesia and continuous spinal anaesthesia are suggested due to better precise control of haemodynamics and quicker onset. However, institution of such complex technique may require time which may not be feasible in emergency situations. Use of bilateral ilioinguinal-iliohypogastric nerve block along with low dose spinal anaesthesia may obviate the need of additional epidural catheter in such complicated cases. We hereby present our experience from two cases.

  20. The role of synoptic/planetary-scale interactions during the development of a blocking anticyclone

    NASA Technical Reports Server (NTRS)

    Tsou, Chih-Hua; Smith, Phillip J.

    1990-01-01

    Consideration is given to the development of a blocking anticyclone over the North Atlantic preceded by explosive cyclogenesis about 500 km south of Nova Scotia during January 19-21, 1979. The general behavior of the block is studied using the extended height tendency equation. The relative importance of planetary-scale, synoptic-scale, and scale-interaction forcing of the block is examined.

  1. Significant role of structural fractures in Ren-Qiu buried-block oil field, eastern China

    SciTech Connect

    Fei, Q.; Xie-Pei, W.

    1983-03-01

    Ren-qui oil field is in a buried block of Sinian (upper Proterozoic) rocks located in the Ji-zhong depression of the western Bohai Bay basin in eastern China. The main reservoir consists of Sinian dolomite rocks. It is a fault block with a large growth fault on the west side which trends north-northeast with throws of up to 1 km (0.6 mi) or more. The source rocks for the oil are Paleogene age and overlie the Sinian dolomite rocks. The structural fractures are the main factor forming the reservoir of the buried-block oil field. Three structural lines, trending northeast, north-northeast, and northwest, form the regional netted fracture system. The north-northeast growth fault controlled the structural development of the buried block. The block was raised and eroded before the Tertiary sediments were deposited. In the Eocene Epoch, the Ji-zhong depression subsided, but the deposition, faulting, and related uplift of the block happened synchronously as the block was gradually submerged. At the same time, several horizontal and vertical karst zones were formed by the karst water along the netted structural fractures. The Eocene oil source rocks lapped onto the block and so the buried block, with many developed karst fractures, was surrounded by a great thickness of source rocks. As the growth fault developed, the height of the block was increased from 400 m (1300 ft) before the Oligocene to 1300 m (4250 ft) after. As the petroleum was generated, it migrated immediately into the karst fractures of the buried block along the growth fault. The karst-fractured block reservoir has an 800-m (2600-ft) high oil-bearing closure and good connections developed between the karst fractures.

  2. Lexical selection in the semantically blocked cyclic naming task: the role of cognitive control and learning

    PubMed Central

    Crowther, Jason E.; Martin, Randi C.

    2014-01-01

    Studies of semantic interference in language production have provided evidence for a role of cognitive control mechanisms in regulating the activation of semantic competitors during naming. The present study investigated the relationship between individual differences in cognitive control abilities, for both younger and older adults, and the degree of semantic interference in a blocked cyclic naming task. We predicted that individuals with lower working memory capacity (as measured by word span), lesser ability to inhibit distracting responses (as measured by Stroop interference), and a lesser ability to resolve proactive interference (as measured by a recent negatives task) would show a greater increase in semantic interference in naming, with effects being larger for older adults. Instead, measures of cognitive control were found to relate to specific indices of semantic interference in the naming task, rather than overall degree of semantic interference, and few interactions with age were found, with younger and older adults performing similarly. The increase in naming latencies across naming trials within a cycle was negatively correlated with word span for both related and unrelated conditions, suggesting a strategy of narrowing response alternatives based upon memory for the set of item names. Evidence for a role of inhibition in response selection was obtained, as Stroop interference correlated positively with the change in naming latencies across cycles for the related, but not unrelated, condition. In contrast, recent negatives interference correlated negatively with the change in naming latencies across unrelated cycles, suggesting that individual differences in this tap the degree of strengthening of links in a lexical network based upon prior exposure. Results are discussed in terms of current models of lexical selection and consequences for word retrieval in more naturalistic production. PMID:24478675

  3. The Roles of Microtubule-Based Transport at Presynaptic Nerve Terminals

    PubMed Central

    Yagensky, Oleksandr; Kalantary Dehaghi, Tahere; Chua, John Jia En

    2016-01-01

    Targeted intracellular movement of presynaptic proteins plays important roles during synapse formation and, later, in the homeostatic maintenance of mature synapses. Movement of these proteins, often as vesicular packages, is mediated by motor complexes travelling along intracellular cytoskeletal networks. Presynaptic protein transport by kinesin motors in particular plays important roles during synaptogenesis to bring newly synthesized proteins to establish nascent synaptic sites. Conversely, movement of proteins away from presynaptic sites by Dynein motors enables synapse-nuclear signaling and allows for synaptic renewal through degradation of unwanted or damaged proteins. Remarkably, recent data has indicated that synaptic and protein trafficking machineries can modulate each other’s functions. Here, we survey the mechanisms involved in moving presynaptic components to and away from synapses and how this process supports presynaptic function. PMID:26903856

  4. Effect of pH of bupivacaine on duration of repeated sciatic nerve blocks in the albino rat. Local Anesthetics for Neuralgia Study Group.

    PubMed

    Baker, C E; Berry, R L; Elston, R C

    1991-06-01

    Tachyphylaxis has been ascribed to tissue acidification after repeated injections of acidic local anesthetic solutions. We studied the effect of pH on the duration of action of bupivacaine to determine the validity of this proposed mechanism of tachyphylaxis by injecting bupivacaine solutions adjusted to pH 4.2 or 6.8 into a surgically implanted system created to permit in vivo irrigation of rat sciatic nerves with local anesthetic. Tachyphylaxis developed at both pH values. The results fail to support the acidification hypothesis as there was no statistically significant effect of a 400-fold difference in hydrogen ion concentration on the development of tachyphylaxis or the duration of motor dysfunction.

  5. Vagus Nerve Stimulation

    PubMed Central

    Howland, Robert H.

    2014-01-01

    The vagus nerve is a major component of the autonomic nervous system, has an important role in the regulation of metabolic homeostasis, and plays a key role in the neuroendocrine-immune axis to maintain homeostasis through its afferent and efferent pathways. Vagus nerve stimulation (VNS) refers to any technique that stimulates the vagus nerve, including manual or electrical stimulation. Left cervical VNS is an approved therapy for refractory epilepsy and for treatment resistant depression. Right cervical VNS is effective for treating heart failure in preclinical studies and a phase II clinical trial. The effectiveness of various forms of non-invasive transcutaneous VNS for epilepsy, depression, primary headaches, and other conditions has not been investigated beyond small pilot studies. The relationship between depression, inflammation, metabolic syndrome, and heart disease might be mediated by the vagus nerve. VNS deserves further study for its potentially favorable effects on cardiovascular, cerebrovascular, metabolic, and other physiological biomarkers associated with depression morbidity and mortality. PMID:24834378

  6. A comparison of two anesthesia methods for the surgical removal of maxillary third molars: PSA nerve block technique vs. local infiltration technique

    PubMed Central

    2014-01-01

    Objectives: The purpose of this study was to compare the effect of PSA block injection with infiltration technique regarding local anesthesia for surgical extraction of upper third molar. Material and Methods: A prospective, intra individual, single-blind randomized controlled trial was designed to study the severity of pain during injection and after surgical extraction of the bilaterally and symmetrically similar upper third molar in a total of 53 patients, in addition to evaluating the need to repeat the injection and requirement of post operative anti-inflammatory tablets. Result: Although the average pain score for all studied times in PSA side was lower than the average pain score in infiltration technique, repeated statistical measures demonstrated that no significant pain reduction occurred in the two techniques. Conclusion: The both tested methods have the same statistic equivalence for the surgical extraction of maxillary third molars. Key words:Surgical extraction, maxillary third molars, PSA block, infiltration. PMID:24596629

  7. Protective effects of an interaction between vagus nerve and melatonin on gastric ischemia/reperfusion: the role of oxidative stress

    PubMed Central

    Shahrokhi, Nader; Khaksari, Mohammad; Nourizad, Shahla; Shahrokhi, Nava; Soltani, Zahra; Gholamhosseinian, Ahmad

    2016-01-01

    Objectives: Vagal pathways in gastrointestinal tract are the most important pathways that regulate ischemia/reperfusion (I/R). Gastrointestinal tract is one of the important sources of melatonin production. The aim of this study was to investigate probable protective effect of the interaction between vagus nerve and melatonin after I/R. Materials and methods: This study was performed in male rats that were divided into six groups. Cervical vagus nerve was cut bilaterally after induction of I/R and the right one was stimulated by stimulator. Melatonin or vehicle was injected intraperitoneally. The stomach was removed for histopathological and biochemical investigations. Results: A significant decrease in infiltration of gastric neutrophils and malondialdehyde (MDA) level after I/R was induced by melatonin and was disappeared after vagotomy. The stimulation of vagus nerve significantly enhanced these effects of melatonin. However, a stimulation of vagus nerve alone increased neutrophils infiltration and MDA level. Melatonin significantly increased the activities of catalase, glutathione peroxidase (GPx), superoxide dismutases (SOD). Unlike stimulation of vagus nerve, vagotomy decreased these effects of melatonin. Conclusion: According to these results, it is probable that protective effects of melatonin after I/R may be mediated by vagus nerve. Therefore, there is an interaction between melatonin and vagus nerve in their protective effects. PMID:27096067

  8. Up-Regulation of Nerve Growth Factor in Cholestatic Livers and Its Hepatoprotective Role against Oxidative Stress

    PubMed Central

    Tsai, Ming-Shian; Lin, Yu-Chun; Sun, Cheuk-Kwan; Huang, Shih-Che; Lee, Po-Huang; Kao, Ying-Hsien

    2014-01-01

    The role of nerve growth factor (NGF) in liver injury induced by bile duct ligation (BDL) remains elusive. This study aimed to investigate the relationship between inflammation and hepatic NGF expression, to explore the possible upstream molecules up-regulating NGF, and to determine whether NGF could protect hepatocytes from oxidative liver injury. Biochemical and molecular detection showed that NGF was up-regulated in cholestatic livers and plasma, and well correlated with systemic and hepatic inflammation. Conversely, systemic immunosuppression reduced serum NGF levels and resulted in higher mortality in BDL-treated mice. Immunohistochemistry showed that the up-regulated NGF was mainly localized in parenchymal hepatocytes. In vitro mechanistic study further demonstrated that TGF-β1 up-regulated NGF expression in clone-9 and primary rat hepatocytes. Exogenous NGF supplementation and endogenous NGF overexpression effectively protected hepatocytes against TGF-β1- and oxidative stress-induced cell death in vitro, along with reduced formation of oxidative adducted proteins modified by 4-HNE and 8-OHdG. TUNEL staining confirmed the involvement of anti-apoptosis in the NGF-exhibited hepatoprotection. Moreover, NGF potently induced Akt phosphorylation and increased Bcl-2 to Bax ratios, whereas these molecular alterations by NGF were only seen in the H2O2-, but not TGF-β1-treated hepatocytes. In conclusion, NGF exhibits anti-oxidative and hepatoprotective effects and is suggested to be therapeutically applicable in treating cholestatic liver diseases. PMID:25397406

  9. Effects of intranasal cocaine on sympathetic nerve discharge in humans.

    PubMed Central

    Jacobsen, T N; Grayburn, P A; Snyder, R W; Hansen, J; Chavoshan, B; Landau, C; Lange, R A; Hillis, L D; Victor, R G

    1997-01-01

    Cocaine-induced cardiovascular emergencies are mediated by excessive adrenergic stimulation. Animal studies suggest that cocaine not only blocks norepinephrine reuptake peripherally but also inhibits the baroreceptors, thereby reflexively increasing sympathetic nerve discharge. However, the effect of cocaine on sympathetic nerve discharge in humans is unknown. In 12 healthy volunteers, we recorded blood pressure and sympathetic nerve discharge to the skeletal muscle vasculature using intraneural microelectrodes (peroneal nerve) during intranasal cocaine (2 mg/kg, n = 8) or lidocaine (2%, n = 4), an internal local anesthetic control, or intravenous phenylephrine (0.5-2.0 microg/kg, n = 4), an internal sympathomimetic control. Experiments were repeated while minimizing the cocaine-induced rise in blood pressure with intravenous nitroprusside to negate sinoaortic baroreceptor stimulation. After lidocaine, blood pressure and sympathetic nerve discharge were unchanged. After cocaine, blood pressure increased abruptly and remained elevated for 60 min while sympathetic nerve discharge initially was unchanged and then decreased progressively over 60 min to a nadir that was only 2+/-1% of baseline (P < 0.05); however, plasma venous norepinephrine concentrations (n = 5) were unchanged up to 60 min after cocaine. Sympathetic nerve discharge fell more rapidly but to the same nadir when blood pressure was increased similarly with phenylephrine. When the cocaine-induced increase in blood pressure was minimized (nitroprusside), sympathetic nerve discharge did not decrease but rather increased by 2.9 times over baseline (P < 0.05). Baroreflex gain was comparable before and after cocaine. We conclude that in conscious humans the primary effect of intranasal cocaine is to increase sympathetic nerve discharge to the skeletal muscle bed. Furthermore, sinoaortic baroreflexes play a pivotal role in modulating the cocaine-induced sympathetic excitation. The interplay between these

  10. Truncal blocks for perioperative pain management: a review of the literature and evolving techniques.

    PubMed

    Go, Ramon; Huang, Yolanda Y; Weyker, Paul D; Webb, Christopher Aj

    2016-10-01

    As the American healthcare system continues to evolve and reimbursement becomes tied to value-based incentive programs, perioperative pain management will become increasingly important. Regional anesthetic techniques are only one component of a successful multimodal pain regimen. In recent years, the use of peripheral and paraneuraxial blocks to provide chest wall and abdominal analgesia has gained popularity. When used within a multimodal regimen, truncal blocks may provide similar analgesia when compared with other regional anesthetic techniques. While there are other reviews that cover this topic, our review will also highlight the emerging role for serratus plane blocks, pectoral nerve blocks and quadratus lumborum blocks in providing thoracic and abdominal analgesia.

  11. Role of S-100 Immunostaining in Demonstration of Nerve Changes and Quantification of Dendritic Cells in Leprosy

    PubMed Central

    Mohanraj, Anand; Srinivasan, Sowmya

    2014-01-01

    Background: A definitive diagnosis of leprosy is based on a demonstration of either acid-fast bacilli or nerve elements within the granulomas. On routine hematoxylin and eosin stains, the nerve fibers are not easily identifiable. In this study, S-100 immunostain is used to highlight the nerve elements and to demonstrate and compare the nerve changes in spectrum of leprosy including reactions. Aim: To demonstrate the nerve changes in spectrum of leprosy using S-100 immunostaining so as to categorize them for the purpose of early diagnosis and treatment. We also want to demonstrate and quantify the dendritic cells in lepromatous spectrum of leprosy using S-100 immunostain. Materials and Methods: Twenty consecutive skin biopsy specimens from patients with histopathological diagnosis of leprosy in the year 2012 were studied. Of these 20 cases, 13 were Borderline Tuberculoid, 1 was of indeterminate leprosy, 1 Borderline Lepromatous, 2 cases of Lepromatous Lep-rosy , 1 case of Type 1 reac-tion and 2 cases of Type 2 reaction. Stains used were Hematoxylin and Eosin stain for the histopathological diagnosis, Fites stain for Bacillary index and S-100 immunoperoxidase staining for nerve changes. 5 cases of granulomatous dermatosis of skin other than leprosy (5 cases of lupus vulgaris) were included as controls. Results: On Hematoxylin and Eosin staining, the nerve fibers showed vertical orientation in relation to epidermis in Borderline Tuberculoid leprosy. In addition , the nerve fibers showed rounded contour in Tuberculoid leprosy. The entire spectrum of leprosy showed evidence of nerve damage in S-100 immunostaining which was categorized in 4 patterns 1. Absent, 2. Fragmented, 3. Discontinuous and 4. Intact. The majority of Borderline Tuberculoid leprosy cases showed absent pattern of nerve damage. Dendritic cells were also positive for S-100 immunostaining with granular positivity in Borderline Tuberculoid Leprosy cases and membranous positivity in Lepromatous spectrum

  12. The role of Ca 2+-related signaling in photodynamic injury of nerve and glial cells

    NASA Astrophysics Data System (ADS)

    Lobanov, A. V.; Petin, Y. O.; Uzdensky, A. B.

    2007-05-01

    Photodynamic therapy (PDT) inhibited and irreversibly abolished firing, caused necrosis of neurons, necrosis, apoptosis and proliferation of glial cells in the isolated crayfish stretch receptor. The role in these processes of the central components of Ca 2+-mediated signaling pathway: phospholipase C, calmodulin, calmodulin-dependent kinase II, and protein kinase C was studied using their inhibitors: ET-18, fluphenazine, KN-93, or staurosporine, respectively. ET-18 reduced functional inactivation of neurons, necrosis and apoptosis of glial cells. Fluphenazine and KN-93 reduced PDT-induced necrosis of neurons and glial cells. Staurosporine enhanced PDT-induced glial apoptosis. PDTinduced gliosis was prevented by KN-93 and staurosporine. Therefore, phospholipase C participated in neuron inactivation and glial necrosis and apoptosis. Calmodulin and calmodulin-dependent kinase II were involved in PDT-induced necrosis of neurons and glial cells but not in glial apoptosis. Protein kinase C protected glia from apoptosis and participated in PDT-induced gliosis and loss of neuronal activity. These data may be used for modulation of PDT of brain tumors.

  13. Differential role of P-glycoprotein and breast cancer resistance protein in drug distribution into brain, CSF and peripheral nerve tissues in rats.

    PubMed

    Huang, Liyue; Li, Xingwen; Roberts, Jonathan; Janosky, Brett; Lin, Min-Hwa Jasmine

    2015-01-01

    1. This study was designed to evaluate how the absence of P-glycoprotein (Pgp, Mdr1a), breast cancer-resistance protein (Bcrp, Abcg2) or both affects drug distribution into sciatic nerves, brain and cerebrospinal fluid (CSF) in rats. 2. Pgp substrate (loperamide), BCRP substrates (dantrolene and proprietary compound X) and dual substrates (imatinib and proprietary compound Y) were well distributed into sciatic nerves with comparable nerve to plasma concentration ratios between wild-type and knockout (KO) rats. 3. Brain exposure increased substantially in Mdr1a(-/-) rats for loperamide and in Mdr1a(-/-)/Abcg2(-/-) rats for imatinib and compound Y, but minimally to modestly in Abcg2(-/-) rats for dantrolene and compound X. The deletion of Mdr1a or Abcg2 alone had little effect on brain distribution of compound Y. 4. While CSF to unbound brain concentration ratio remained ≥3 in the KO animals for dantrolene, compounds X and Y, it was reduced to 1 in the Mdr1a(-/-)/Abcg2(-/-) rats for imatinib. 5. The data indicate that Pgp and Bcrp do not play significant roles in drug distribution into peripheral nerve tissues in rats, while working in concert to regulate brain penetration. Our results further support that CSF concentration may not be a good surrogate for unbound brain concentration of efflux substrates.

  14. Control of active sites in selective flocculation: II -- Role of site blocking agents

    SciTech Connect

    Behl, S.; Moudgil, B.M. . Dept. of Materials Science and Engineering)

    1993-12-01

    Control of heteroflocculation using a lower molecular weight fraction of the flocculant as a site blocking agent is demonstrated in the apatite-dolomite-polyethylene oxide system. The most effective SBA (site blocking agent) was determined to be the highest molecular weight fraction of the flocculant itself which was not capable of flocculating any of the components of the mixture. In the presence of the SBA, flocculant adsorption decreased significantly on apatite particles, thereby inhibiting coflocculation.

  15. Subaxolemmal filamentous network in the giant nerve fiber of the squid (Loligo pealei L.) and its possible role in excitability

    PubMed Central

    1978-01-01

    A new technique utilizing the squid giant nerve fiber has been developed which permits direct examination of the inner face of the axolemma by scanning electron microscopy. The axoplasm was removed sequentially in a 15-mm long segment of the fiber by intracellular perfusion with a solution of KF, KCl, Ca++-containing seawater, or with pronase. The action potential of the fibers was monitored during these treatments. After brief prefixation in 1% paraformaldehyde and 1% glutaraldehyde, the perfused segment was opened by a lne could be related to information on the detailed morphology of the cytoplasmic face of the axolemma and the ectoplasm. The results obtained by scanning electron microscopy were further substantiated by transmission electron microscopy of thin sections. In addition, living axons were studied with polarized light during axoplasm removal, and the identification of actin by heavy meromyosin labeling and sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis was accomplished. These observations demonstrate that a three-dimensional network of interwoven filaments, consisting partly of an actinlike protein, is firmly attached to the axolemma. The axoplasmic face of fibers in which the filaments have been removed partially after perfusion with pronase displays smooth membranous blebs and large profiles which sppose the axolemma. In fibers where the excitability has been suppressed by pronase perfusion, approximately one-third of the inner face of the axolemma in the perfusion zone is free of filaments. It is hypothesized that the attachment of axoplasm filaments to the axolemma may have a role in the maintenance of the normal morphology of the axolemma, and, thus, in some aspect of excitability. PMID:690181

  16. Comparison of the effects of remifentanil-based general anesthesia and popliteal nerve block on postoperative pain and hemodynamic stability in diabetic patients undergoing distal foot amputation: A retrospective observational study.

    PubMed

    Kim, Na Young; Lee, Ki-Young; Bai, Sun Joon; Hong, Jung Hwa; Lee, Jinwoo; Park, Jong Min; Kim, Shin Hyung

    2016-07-01

    Diabetic foot ulcer is the most common cause of diabetes-associated nontraumatic lower extremity amputation. Most patients who undergo lower extremity amputation for a diabetic foot have had diabetes for a long time and suffer from multiorgan disorder; thus, it can be a challenge to ensure sufficient anesthetic and analgesic effects while maintaining stable hemodynamics. Recently, peripheral nerve block has gained popularity owing to its attenuating effects of systemic concerns. This retrospective observational study aimed to compare the effects of remifentanil-based general anesthesia (GEA) and popliteal nerve block (PNB) on postoperative pain and hemodynamic stability in diabetic patients undergoing distal foot amputation.A total of 59 consecutive patients with a diabetic foot who underwent distal foot amputation between January 2012 and May 2014 were retrospectively reviewed. Patients received remifentanil-based GEA (GEA group, n = 32) or PNB (PNB group, n = 27). The primary outcomes were to evaluate postoperative analgesic effects and perioperative hemodynamics. Also, postoperative pulmonary complications and 6-month mortality were assessed as secondary outcomes.Significant differences in pain scores using numeric rating scale were observed between the groups in a linear mixed model analysis (PGroup×Time = 0.044). Even after post hoc analysis with the Bonferroni correction, the numeric rating scale scores were significantly lower in the PNB group. Furthermore, patients in the PNB group required less pethidine during the first 6 hours after surgery (27 ± 28 vs 9 ± 18 mg; P = 0.013). The GEA group had a lower mean blood pressure (Bonferroni-corrected P < 0.01), despite receiving more ephedrine (P < 0.001). Significantly more patients in the GEA group suffered from postoperative pneumonia and required the management in intensive care unit (P = 0.030 and 0.038, respectively). However, the groups did not differ in terms of

  17. Thermodynamics of Surfactants, Block Copolymers and Their Mixtures in Water: The Role of the Isothermal Calorimetry

    PubMed Central

    De Lisi, Rosario; Milioto, Stefania; Muratore, Nicola

    2009-01-01

    The thermodynamics of conventional surfactants, block copolymers and their mixtures in water was described to the light of the enthalpy function. The two methodologies, i.e. the van’t Hoff approach and the isothermal calorimetry, used to determine the enthalpy of micellization of pure surfactants and block copolymers were described. The van’t Hoff method was critically discussed. The aqueous copolymer+surfactant mixtures were analyzed by means of the isothermal titration calorimetry and the enthalpy of transfer of the copolymer from the water to the aqueous surfactant solutions. Thermodynamic models were presented to show the procedure to extract straightforward molecular insights from the bulk properties. PMID:19742173

  18. The Role of the Mesentery in Crohn's Disease: The Contributions of Nerves, Vessels, Lymphatics, and Fat to the Pathogenesis and Disease Course.

    PubMed

    Li, Yi; Zhu, Weiming; Zuo, Lugen; Shen, Bo

    2016-06-01

    Crohn's disease (CD) is a complex gastrointestinal disorder involving multiple levels of cross talk between the immunological, neural, vascular, and endocrine systems. The current dominant theory in CD is based on the unidirectional axis of dysbiosis-innate immunity-adaptive immunity-mesentery-body system. Emerging clinical evidence strongly suggests that the axis be bidirectional. The morphologic and/or functional abnormalities in the mesenteric structures likely contribute to the disease progression of CD, to a less extent the disease initiation. In addition to adipocytes, mesentery contains nerves, blood vessels, lymphatics, stromal cells, and fibroblasts. By the secretion of adipokines that have endocrine functions, the mesenteric fat tissue exerts its activity in immunomodulation mainly through response to afferent signals, neuropeptides, and functional cytokines. Mesenteric nerves are involved in the pathogenesis and prognosis of CD mainly through neuropeptides. In addition to angiogenesis observed in CD, lymphatic obstruction, remodeling, and impaired contraction maybe a cause and consequence of CD. Lymphangiogenesis and angiogenesis play a concomitant role in the progress of chronic intestinal inflammation. Finally, the interaction between neuropeptides, adipokines, and vascular and lymphatic endothelia leads to adipose tissue remodeling, which makes the mesentery an active participator, not a bystander, in the disease initiation and precipitation CD. The identification of the role of mesentery, including the structure and function of mesenteric nerves, vessels, lymphatics, and fat, in the intestinal inflammation in CD has important implications in understanding its pathogenesis and clinical management. PMID:27167572

  19. The Role of Postoperative Radiotherapy for Large Nerve Perineural Spread of Cancer of the Head and Neck.

    PubMed

    Gorayski, Peter; Foote, Matthew; Porceddu, Sandro; Poulsen, Michael

    2016-04-01

    Large nerve perineural spread (LNPNS) is an uncommon but serious sequelae of cutaneous and salivary gland malignancies arising in the head and neck. This distinct clinical entity is caused by malignant cell spread along the course of larger (named) cranial nerves in a bidirectional pattern of spread toward the origins of the nerve in the brainstem and/or its most distal branches residing in the dermis. Untreated, LNPNS causes multiple cranial neuropathies that significantly impact on quality of life and ultimately is fatal. Curative treatment involves en bloc surgical resection of all known involved sites of gross disease followed by risk-adapted postoperative radiotherapy (PORT) to improve local control. We review the evidence for contemporary practice and outline the processes involved in the delivery of PORT using the zonal anatomical classification. PMID:27123394

  20. The role of the chorda tympani nerve in the activation of the rat hypothalamic histaminergic system by leptin.

    PubMed

    Morimoto-Ishizuka, T; Yamamoto, Y; Yamatodani, A

    2001-03-01

    A possible pathway through which leptin activates the histaminergic system was studied using in vivo microdialysis in rats. Intraperitoneal injection of leptin (1.3 mg/kg) caused a significant increase in hypothalamic histamine release, however, its intracerebroventricular injection (10 microg/rat) did not cause any significant changes in the release. Furthermore, leptin (1.3 mg/kg) had no effect on histamine release in rats whose chorda tympani nerves, a branch of the facial nerve which mediates taste information, were transected bilaterally. These findings indicate that leptin activates the histaminergic system by the peripheral signal inputs via the chorda tympani resulting in the suppression of food intake.

  1. The Role of Hypothalamic mTORC1 Signaling in Insulin Regulation of Food Intake, Body Weight, and Sympathetic Nerve Activity in Male Mice

    PubMed Central

    Muta, Kenjiro; Morgan, Donald A.

    2015-01-01

    Insulin action in the brain particularly the hypothalamus is critically involved in the regulation of several physiological processes, including energy homeostasis and sympathetic nerve activity, but the underlying mechanisms are poorly understood. The mechanistic target of rapamycin complex 1 (mTORC1) is implicated in the control of diverse cellular functions, including sensing nutrients and energy status. Here, we examined the role of hypothalamic mTORC1 in mediating the anorectic, weight-reducing, and sympathetic effects of central insulin action. In a mouse hypothalamic cell line (GT1–7), insulin treatment increased mTORC1 activity in a time-dependent manner. In addition, intracerebroventricular (ICV) administration of insulin to mice activated mTORC1 pathway in the hypothalamic arcuate nucleus, a key site of central action of insulin. Interestingly, inhibition of hypothalamic mTORC1 with rapamycin reversed the food intake- and body weight-lowering effects of ICV insulin. Rapamycin also abolished the ability of ICV insulin to cause lumbar sympathetic nerve activation. In GT1–7 cells, we found that insulin activation of mTORC1 pathway requires phosphatidylinositol 3-kinase (PI3K). Consistent with this, genetic disruption of PI3K in mice abolished insulin stimulation of hypothalamic mTORC1 signaling as well as the lumbar sympathetic nerve activation evoked by insulin. These results demonstrate the importance of mTORC1 pathway in the hypothalamus in mediating the action of insulin to regulate energy homeostasis and sympathetic nerve traffic. Our data also highlight the key role of PI3K as a link between insulin receptor and mTORC1 signaling in the hypothalamus. PMID:25574706

  2. Hepatic Branch Vagus Nerve Plays a Critical Role in the Recovery of Post-Ischemic Glucose Intolerance and Mediates a Neuroprotective Effect by Hypothalamic Orexin-A

    PubMed Central

    Harada, Shinichi; Yamazaki, Yui; Koda, Shuichi; Tokuyama, Shogo

    2014-01-01

    Orexin-A (a neuropeptide in the hypothalamus) plays an important role in many physiological functions, including the regulation of glucose metabolism. We have previously found that the development of post-ischemic glucose intolerance is one of the triggers of ischemic neuronal damage, which is suppressed by hypothalamic orexin-A. Other reports have shown that the communication system between brain and peripheral tissues through the autonomic nervous system (sympathetic, parasympathetic and vagus nerve) is important for maintaining glucose and energy metabolism. The aim of this study was to determine the involvement of the hepatic vagus nerve on hypothalamic orexin-A-mediated suppression of post-ischemic glucose intolerance development and ischemic neuronal damage. Male ddY mice were subjected to middle cerebral artery occlusion (MCAO) for 2 h. Intrahypothalamic orexin-A (5 pmol/mouse) administration significantly suppressed the development of post-ischemic glucose intolerance and neuronal damage on day 1 and 3, respectively after MCAO. MCAO-induced decrease of hepatic insulin receptors and increase of hepatic gluconeogenic enzymes on day 1 after was reversed to control levels by orexin-A. This effect was reversed by intramedullary administration of the orexin-1 receptor antagonist, SB334867, or hepatic vagotomy. In the medulla oblongata, orexin-A induced the co-localization of cholin acetyltransferase (cholinergic neuronal marker used for the vagus nerve) with orexin-1 receptor and c-Fos (activated neural cells marker). These results suggest that the hepatic branch vagus nerve projecting from the medulla oblongata plays an important role in the recovery of post-ischemic glucose intolerance and mediates a neuroprotective effect by hypothalamic orexin-A. PMID:24759941

  3. Nerve conduction

    MedlinePlus

    ... fascicles) that contain hundreds of individual nerve fibers (neurons). Neurons consist of dendrites, axon, and cell body. The ... tree-like structures that receive signals from other neurons and from special sensory cells that sense the ...

  4. Hypertrophy of Neurons Within Cardiac Ganglia in Human, Canine, and Rat Heart Failure: The Potential Role of Nerve Growth Factor

    PubMed Central

    Singh, Sanjay; Sayers, Scott; Walter, James S.; Thomas, Donald; Dieter, Robert S.; Nee, Lisa M.; Wurster, Robert D.

    2013-01-01

    Background Autonomic imbalances including parasympathetic withdrawal and sympathetic overactivity are cardinal features of heart failure regardless of etiology; however, mechanisms underlying these imbalances remain unknown. Animal model studies of heart and visceral organ hypertrophy predict that nerve growth factor levels should be elevated in heart failure; whether this is so in human heart failure, though, remains unclear. We tested the hypotheses that neurons in cardiac ganglia are hypertrophied in human, canine, and rat heart failure and that nerve growth factor, which we hypothesize is elevated in the failing heart, contributes to this neuronal hypertrophy. Methods and Results Somal morphology of neurons from human (579.54±14.34 versus 327.45±9.17 μm2; P<0.01) and canine hearts (767.80±18.37 versus 650.23±9.84 μm2; P<0.01) failing secondary to ischemia and neurons from spontaneously hypertensive rat hearts (327.98±3.15 versus 271.29±2.79 μm2; P<0.01) failing secondary to hypertension reveal significant hypertrophy of neurons in cardiac ganglia compared with controls. Western blot analysis shows that nerve growth factor levels in the explanted, failing human heart are 250% greater than levels in healthy donor hearts. Neurons from cardiac ganglia cultured with nerve growth factor are significantly larger and have greater dendritic arborization than neurons in control cultures. Conclusions Hypertrophied neurons are significantly less excitable than smaller ones; thus, hypertrophy of vagal postganglionic neurons in cardiac ganglia would help to explain the parasympathetic withdrawal that accompanies heart failure. Furthermore, our observations suggest that nerve growth factor, which is elevated in the failing human heart, causes hypertrophy of neurons in cardiac ganglia. PMID:23959444

  5. The role of diagnostic block in the management of Morton’s neuroma

    PubMed Central

    Younger, Alastair S.E.; Claridge, Richard J.

    1998-01-01

    Objective To determine the outcome of surgical excision of Morton’s neuroma after a local anesthetic diagnostic block into the neuroma has relieved symptoms. Design A cohort study. Setting A university affiliated hospital. Patients A sequential series of 37 patients who underwent 41 excisions with at least 2 years’ follow-up. Seven patients had undergone repeat excision of a neuroma, and 34 primary excisions were performed. Surgery was performed by a specialist in orthopedic surgery of the foot and ankle. Intervention Excision of the Morton’s neuroma after a positive diagnostic block. Main outcome measures Grade of symptoms at follow-up done by independent review on a 4-point scale. Results Of 41 procedures, 11 had an unfavourable outcome: 4 procedures were graded 3, and 7 procedures were graded 4. Eight (24%) of the 34 primary procedures were reported as failures, and 3 (43%) of the 7 revision procedures were reported as failures. Most patients reported poor results owing to persistent pain. Conclusions Diagnostic blocks do not improve the results of surgery for excision of Morton’s neuroma and are not recommended. Because failure rates are greater than 20%, surgery for Morton’s neuroma should only be offered after a full course of nonoperative management. PMID:9575995

  6. Roles of European blocking and tropical-extratropical interaction in the 2010 Pakistan flooding

    NASA Astrophysics Data System (ADS)

    Hong, Chi-Cherng; Hsu, Huang-Hsiung; Lin, Nai-Hsin; Chiu, Hsun

    2011-07-01

    A sequence of monsoon surges struck Pakistan and Northwestern India during late July-early August 2010. The unusually heavy monsoon rainfall resulted in record-breaking floods, which affected 20 million people with a death toll of near 3000. Simultaneously, a long-lived blocking high appeared over Europe and Russia in middle June and persisted for nearly two months. Extreme flooding occurred when the southward penetration of extratropical potential vorticity in the deep trough east of the European blocking and the tropical monsoon surges arrived concurrently in Pakistan. This study demonstrates that the interaction between the tropical monsoon surges and the extratropical disturbances downstream of the European blocking was the key factor leading to the severe flooding in Pakistan. The 2010 La Niña condition contributed indirectly to the flooding by inducing a low-level easterly anomaly in South and Southeast Asia, which weakened eastward moisture transport and helped enhance moisture transport (convergence) to (in) the Northern Arabian Sea and Pakistan.

  7. The role of sympathetic and parasympathetic nerve systems on the smooth muscle of rat seminal vesicles - experimental results and speculation for physiological implication on ejaculation.

    PubMed

    Hsieh, J-T; Kuo, Y-C; Chang, H-C; Liu, S-P; Chen, J-H; Tsai, V F S

    2014-01-01

    Ejaculation is a process involving sympathetic and parasympathetic effects during different stages - emission and ejection. Some conditions of ejaculation dysfunction are associated with autonomic nerves. However, the exact effects of autonomic nerves on ejaculation are not well defined. Autonomic agonists induce different recorded trace patterns of seminal vesicular contraction. The different traces contain different components of phasic and tonic contraction, which may have physiological implications. In this study, we examined isolated rat seminal vesicle (SV) contraction by phenylephrine (PE), acetylcholine, and their respective antagonists and then speculated upon physiological roles of sympathetic and parasympathetic nerves on SV during ejaculation. We found that PE and Ach both achieved good contraction of rat SV. Compared to α1b for sympathetic and M1, M2 for parasympathetic receptors, α1a and M3 are the relatively dominant subtypes on rat SV. Adrenergic and cholinergic agonists cause different trace patterns of SV contraction. We speculated that the sympathetic effect is dominant during emission to squeeze seminal fluid out and that the parasympathetic effect is dominant during ejection to provide an anti-reflux effect on the ejaculatory duct.

  8. Alcohol neurolysis of digital nerves

    PubMed Central

    Wright, Garrett K.; Burnett, Christopher J.

    2016-01-01

    Alcohol neurolysis is a well-established treatment in chronic pain management, often used in cases of intractable cancer-related pain that is refractory to other management therapies. We describe a 76-year-old woman with chronic toe neuritis who failed multiple treatments, including oral and topical analgesics, nerve blocks, and radiofrequency ablations. Alcohol neurolysis was performed via digit block of the toe resulting in 100% pain relief. PMID:27365891

  9. The trophic influence of tetrodotoxin-inactive nerves on normal and reinnervated rat skeletal muscles.

    PubMed Central

    Bray, J J; Hubbard, J I; Mills, R G

    1979-01-01

    1. Nerve impulses in the rat sciatic nerve were blocked for long periods by tetrodotoxin (TTX) released from capillary implants. The TTX capillaries did not block axonal transport, nor did they cause any sign of nerve degeneration. 2. A comparison of the effects of TTX paralysis and denervation was made on both extensor digitorium longus (e.d.l.) and soleus muscles over 21 days, a time when the products of nerve degeneration were unlikely to contribute to the changes associated with denervation. The resting membrane potential of TTX-paralysed muscles was significantly different (P less than 0.005) from that of the denervated muscles at all periods and at 21 days the decrease that can be attributed to inactivity was 61% (e.d.l.) and 49% (soleus) of that which follows denervation. This disparity was even more pronounced for the ACh receptor density where the increase in receptors due to inactivity was only 34% (e.d.l.) and 21% (soleus) of that due to denervation. 3. A similar comparison was made on muscles which had been reinnervated by TTX-inactive nerves. These muscles were found to have a significantly higher resting membrane potential and lower ACh receptor density than the denervated muscles (P less than 0.05). 4. The experiments on reinnervated muscles preclude the possibility that nerve degeneration products are solely responsible for the difference between the TTX-paralysed and denervated muscles and suggest that the difference can be attributed to the trophic influence of the nerve. 5. An observed increase in the m.e.p.p. frequency of the TTX-paralysed muscles indicated that nerve action potentials play a role in regulating the spontaneous release from nerve terminals. PMID:94092

  10. Ephaptic coupling of myelinated nerve fibers

    NASA Astrophysics Data System (ADS)

    Binczak, S.; Eilbeck, J. C.; Scott, A. C.

    2001-01-01

    Numerical predictions of a simple myelinated nerve fiber model are compared with theoretical results in the continuum and discrete limits, clarifying the nature of the conduction process on an isolated nerve axon. Since myelinated nerve fibers are often arranged in bundles, this model is used to study ephaptic (nonsynaptic) interactions between impulses on parallel fibers, which may play a functional role in neural processing.

  11. Sympathetic nerve stimulation induces local endothelial Ca2+ signals to oppose vasoconstriction of mouse mesenteric arteries

    PubMed Central

    Nausch, Lydia W. M.; Bonev, Adrian D.; Heppner, Thomas J.; Tallini, Yvonne; Kotlikoff, Michael I.

    2012-01-01

    It is generally accepted that the endothelium regulates vascular tone independent of the activity of the sympathetic nervous system. Here, we tested the hypothesis that the activation of sympathetic nerves engages the endothelium to oppose vasoconstriction. Local inositol 1,4,5-trisphosphate (IP3)-mediated Ca2+ signals (“pulsars”) in or near endothelial projections to vascular smooth muscle (VSM) were measured in an en face mouse mesenteric artery preparation. Electrical field stimulation of sympathetic nerves induced an increase in endothelial cell (EC) Ca2+ pulsars, recruiting new pulsar sites without affecting activity at existing sites. This increase in Ca2+ pulsars was blocked by bath application of the α-adrenergic receptor antagonist prazosin or by TTX but was unaffected by directly picospritzing the α-adrenergic receptor agonist phenylephrine onto the vascular endothelium, indicating that nerve-derived norepinephrine acted through α-adrenergic receptors on smooth muscle cells. Moreover, EC Ca2+ signaling was not blocked by inhibitors of purinergic receptors, ryanodine receptors, or voltage-dependent Ca2+ channels, suggesting a role for IP3, rather than Ca2+, in VSM-to-endothelium communication. Block of intermediate-conductance Ca2+-sensitive K+ channels, which have been shown to colocalize with IP3 receptors in endothelial projections to VSM, enhanced nerve-evoked constriction. Collectively, our results support the concept of a transcellular negative feedback module whereby sympathetic nerve stimulation elevates EC Ca2+ signals to oppose vasoconstriction. PMID:22140050

  12. Complement components of nerve regeneration conditioned fluid influence the microenvironment of nerve regeneration

    PubMed Central

    Li, Guang-shuai; Li, Qing-feng; Dong, Ming-min; Zan, Tao; Ding, Shuang; Liu, Lin-bo

    2016-01-01

    Nerve regeneration conditioned fluid is secreted by nerve stumps inside a nerve regeneration chamber. A better understanding of the proteinogram of nerve regeneration conditioned fluid can provide evidence for studying the role of the microenvironment in peripheral nerve regeneration. In this study, we used cylindrical silicone tubes as the nerve regeneration chamber model for the repair of injured rat sciatic nerve. Isobaric tags for relative and absolute quantitation proteomics technology and western blot analysis confirmed that there were more than 10 complement components (complement factor I, C1q-A, C1q-B, C2, C3, C4, C5, C7, C8β and complement factor D) in the nerve regeneration conditioned fluid and each varied at different time points. These findings suggest that all these complement components have a functional role in nerve regeneration. PMID:27212935

  13. Peripheral nerve imaging: Not only cross-sectional area.

    PubMed

    Tagliafico, Alberto Stefano

    2016-08-28

    Peripheral nerve imaging is recognized as a complement to clinical and neurophysiological assessment in the evaluation of peripheral nerves with the ability to impact patient management, even for small and difficult nerves. The European Society of Musculoskeletal Radiology, suggest to use ultrasound (US) for nerve evaluation due to the fact that, in sever anatomical area, magnetic resonance imaging is not able to give additional informations. US could be considered the first-choice approach for the assessment of peripheral nerves. The relative drawback of peripheral nerve US is the long learning curve and the deep anatomic competence to evaluate even small nerves. In the recent years, the role of US in peripheral nerve evaluation has been widened. In the past, nerve US was mainly used to assess nerve-cross sectional area, but now more advanced measurements and considerations are desirable and can boost the role of peripheral nerve US. Nerve echotexture evaluation was defined in 2010: The ratio between the hypoechoic and hyperechoic areas of peripheral nerves on US was called "nerve density". For evaluation of patients who have peripheral neuropathies, the role of peripheral nerve is US wider than simple cross-sectional area evaluation. Quantitative measurements describing the internal fascicular echotexture of peripheral nerves introduce the concept of considering US as a possible quantitative imaging biomarker technique. The potential of nerve US has started to be uncovered. It seems clear that only cross-sectional area measurement is no more sufficient for a comprehensive US evaluation of peripheral nerves.

  14. Peripheral nerve imaging: Not only cross-sectional area

    PubMed Central

    Tagliafico, Alberto Stefano

    2016-01-01

    Peripheral nerve imaging is recognized as a complement to clinical and neurophysiological assessment in the evaluation of peripheral nerves with the ability to impact patient management, even for small and difficult nerves. The European Society of Musculoskeletal Radiology, suggest to use ultrasound (US) for nerve evaluation due to the fact that, in sever anatomical area, magnetic resonance imaging is not able to give additional informations. US could be considered the first-choice approach for the assessment of peripheral nerves. The relative drawback of peripheral nerve US is the long learning curve and the deep anatomic competence to evaluate even small nerves. In the recent years, the role of US in peripheral nerve evaluation has been widened. In the past, nerve US was mainly used to assess nerve-cross sectional area, but now more advanced measurements and considerations are desirable and can boost the role of peripheral nerve US. Nerve echotexture evaluation was defined in 2010: The ratio between the hypoechoic and hyperechoic areas of peripheral nerves on US was called “nerve density”. For evaluation of patients who have peripheral neuropathies, the role of peripheral nerve is US wider than simple cross-sectional area evaluation. Quantitative measurements describing the internal fascicular echotexture of peripheral nerves introduce the concept of considering US as a possible quantitative imaging biomarker technique. The potential of nerve US has started to be uncovered. It seems clear that only cross-sectional area measurement is no more sufficient for a comprehensive US evaluation of peripheral nerves.

  15. Peripheral nerve imaging: Not only cross-sectional area.

    PubMed

    Tagliafico, Alberto Stefano

    2016-08-28

    Peripheral nerve imaging is recognized as a complement to clinical and neurophysiological assessment in the evaluation of peripheral nerves with the ability to impact patient management, even for small and difficult nerves. The European Society of Musculoskeletal Radiology, suggest to use ultrasound (US) for nerve evaluation due to the fact that, in sever anatomical area, magnetic resonance imaging is not able to give additional informations. US could be considered the first-choice approach for the assessment of peripheral nerves. The relative drawback of peripheral nerve US is the long learning curve and the deep anatomic competence to evaluate even small nerves. In the recent years, the role of US in peripheral nerve evaluation has been widened. In the past, nerve US was mainly used to assess nerve-cross sectional area, but now more advanced measurements and considerations are desirable and can boost the role of peripheral nerve US. Nerve echotexture evaluation was defined in 2010: The ratio between the hypoechoic and hyperechoic areas of peripheral nerves on US was called "nerve density". For evaluation of patients who have peripheral neuropathies, the role of peripheral nerve is US wider than simple cross-sectional area evaluation. Quantitative measurements describing the internal fascicular echotexture of peripheral nerves introduce the concept of considering US as a possible quantitative imaging biomarker technique. The potential of nerve US has started to be uncovered. It seems clear that only cross-sectional area measurement is no more sufficient for a comprehensive US evaluation of peripheral nerves. PMID:27648165

  16. Peripheral nerve imaging: Not only cross-sectional area

    PubMed Central

    Tagliafico, Alberto Stefano

    2016-01-01

    Peripheral nerve imaging is recognized as a complement to clinical and neurophysiological assessment in the evaluation of peripheral nerves with the ability to impact patient management, even for small and difficult nerves. The European Society of Musculoskeletal Radiology, suggest to use ultrasound (US) for nerve evaluation due to the fact that, in sever anatomical area, magnetic resonance imaging is not able to give additional informations. US could be considered the first-choice approach for the assessment of peripheral nerves. The relative drawback of peripheral nerve US is the long learning curve and the deep anatomic competence to evaluate even small nerves. In the recent years, the role of US in peripheral nerve evaluation has been widened. In the past, nerve US was mainly used to assess nerve-cross sectional area, but now more advanced measurements and considerations are desirable and can boost the role of peripheral nerve US. Nerve echotexture evaluation was defined in 2010: The ratio between the hypoechoic and hyperechoic areas of peripheral nerves on US was called “nerve density”. For evaluation of patients who have peripheral neuropathies, the role of peripheral nerve is US wider than simple cross-sectional area evaluation. Quantitative measurements describing the internal fascicular echotexture of peripheral nerves introduce the concept of considering US as a possible quantitative imaging biomarker technique. The potential of nerve US has started to be uncovered. It seems clear that only cross-sectional area measurement is no more sufficient for a comprehensive US evaluation of peripheral nerves. PMID:27648165

  17. The Role of Lumbar Sympathetic Nerves in Regulation of Blood Flow to Skeletal Muscle during Anaphylactic Hypotension in Anesthetized Rats.

    PubMed

    Song, Jie; Tanida, Mamoru; Shibamoto, Toshishige; Zhang, Tao; Wang, Mofei; Kuda, Yuhichi; Kurata, Yasutaka

    2016-01-01

    During hypovolemic shock, skeletal muscle blood flow could be redistributed to vital organs via vasoconstriction in part evoked by activation of the innervating sympathetic nerve activity. However, it is not well known whether this mechanism operates during anaphylactic shock. We determined the femoral artery blood flow (FBF) and lumbar sympathetic nerve activity (LSNA) mainly regulating the hindquater muscle blood flow during anaphylactic hypotension in anesthetized rats. Anesthetized Sprague-Dawley rats were randomly allocated to the following groups (n = 7/group): (1) non-sensitized, (2) anaphylaxis, (3) anaphylaxis-lumbar sympathectomy (LS) and (4) anaphylaxis-sinoaortic denervation (SAD) groups. Anaphylaxis was induced by an intravenous injection of the ovalbumin antigen to the sensitized rats. The systemic arterial pressure (SAP), heart rate (HR), central venous pressure (CVP), FBF and LSNA were continuously measured. In the anaphylaxis group, LSNA and HR increased, while SAP and FBF decreased after antigen injection. In the anaphylaxis-SAD group, LSNA did not significantly change during the early phase, but the responses of SAP and FBF were similar to those in the anaphylaxis group. In the anaphylaxis-LS group, both FBF and SAP decreased similarly to the anaphylaxis group during anaphylactic hypotension. These results indicated that LSNA increased via baroreceptor reflex, but this sympathoexcitation or LS did not affect antigen-induced decreases in FBF or SAP. Lumbar sympathetic nerves are not involved in regulation of the blood flow to the hindlimb or systemic blood pressure during anaphylactic hypotension in anesthetized rats. PMID:26998924

  18. Ion Channels in Nerve Membranes

    ERIC Educational Resources Information Center

    Ehrenstein, Gerald

    1976-01-01

    Discusses research that indicates that nerve membranes, which play a key role in the conduction of impulses, are traversed by protein channels with ion pathways opened and closed by the membrane electric field. (Author/MLH)

  19. Role of block copolymer adsorption versus bimodal grafting on nanoparticle self-assembly in polymer nanocomposites.

    PubMed

    Zhao, Dan; Di Nicola, Matteo; Khani, Mohammad M; Jestin, Jacques; Benicewicz, Brian C; Kumar, Sanat K

    2016-09-14

    We compare the self-assembly of silica nanoparticles (NPs) with physically adsorbed polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP) copolymers (BCP) against NPs with grafted bimodal (BM) brushes comprised of long, sparsely grafted PS chains and a short dense carpet of P2VP chains. As with grafted NPs, the dispersion state of the BCP NPs can be facilely tuned in PS matrices by varying the PS coverage on the NP surface or by changes in the ratio of the PS graft to matrix chain lengths. Surprisingly, the BCP NPs are remarkably better dispersed than the NPs tethered with bimodal brushes at comparable PS grafting densities. We postulate that this difference arises because of two factors inherent in the synthesis of the NPs: In the case of the BCP NPs the adsorption process is analogous to the chains being "grafted to" the NP surface, while the BM case corresponds to "grafting from" the surface. We have shown that the "grafted from" protocol yields patchy NPs even if the graft points are uniformly placed on each particle. This phenomenon, which is caused by chain conformation fluctuations, is exacerbated by the distribution function associated with the (small) number of grafts per particle. In contrast, in the case of BCP adsorption, each NP is more uniformly coated by a P2VP monolayer driven by the strongly favorable P2VP-silica interactions. Since each P2VP block is connected to a PS chain we conjecture that these adsorbed systems are closer to the limit of spatially uniform sparse brush coverage than the chemically grafted case. We finally show that the better NP dispersion resulting from BCP adsorption leads to larger mechanical reinforcement than those achieved with BM particles. These results emphasize that physical adsorption of BCPs is a simple, effective and practically promising strategy to direct NP dispersion in a chemically unfavorable polymer matrix. PMID:27502154

  20. Peripheral Nerve Disorders

    MedlinePlus

    ... spinal cord. Like static on a telephone line, peripheral nerve disorders distort or interrupt the messages between the brain ... body. There are more than 100 kinds of peripheral nerve disorders. They can affect one nerve or many nerves. ...

  1. Nerve biopsy (image)

    MedlinePlus

    Nerve biopsy is the removal of a small piece of nerve for examination. Through a small incision, a sample ... is removed and examined under a microscope. Nerve biopsy may be performed to identify nerve degeneration, identify ...

  2. Nerve growth factor displays stimulatory effects on human skin and lung fibroblasts, demonstrating a direct role for this factor in tissue repair

    NASA Astrophysics Data System (ADS)

    Micera, Alessandra; Vigneti, Eliana; Pickholtz, Dalia; Reich, Reuven; Pappo, Orit; Bonini, Sergio; Maquart, François Xavier; Aloe, Luigi; Levi-Schaffer, Francesca

    2001-05-01

    Nerve growth factor (NGF) is a polypeptide which, in addition to its effect on nerve cells, is believed to play a role in inflammatory responses and in tissue repair. Because fibroblasts represent the main target and effector cells in these processes, to investigate whether NGF is involved in lung and skin tissue repair, we studied the effect of NGF on fibroblast migration, proliferation, collagen metabolism, modulation into myofibroblasts, and contraction of collagen gel. Both skin and lung fibroblasts were found to produce NGF and to express tyrosine kinase receptor (trkA) under basal conditions, whereas the low-affinity p75 receptor was expressed only after prolonged NGF exposure. NGF significantly induced skin and lung fibroblast migration in an in vitro model of wounded fibroblast and skin migration in Boyden chambers. Nevertheless NGF did not influence either skin or lung fibroblast proliferation, collagen production, or metalloproteinase production or activation. In contrast, culture of both lung and skin fibroblasts with NGF modulated their phenotype into myofibroblasts. Moreover, addition of NGF to both fibroblast types embedded in collagen gel increased their contraction. Fibrotic human lung or skin tissues displayed immunoreactivity for NGF, trkA, and p75. These data show a direct pro-fibrogenic effect of NGF on skin and lung fibroblasts and therefore indicate a role for NGF in tissue repair and fibrosis.

  3. Evidence for the role of lipid rafts and sphingomyelin in Ca2+-gating of Transient Receptor Potential channels in trigeminal sensory neurons and peripheral nerve terminals.

    PubMed

    Sághy, Éva; Szőke, Éva; Payrits, Maja; Helyes, Zsuzsanna; Börzsei, Rita; Erostyák, János; Jánosi, Tibor Zoltán; Sétáló, György; Szolcsányi, János

    2015-10-01

    Transient Receptor Potential (TRP) cation channels, such as TRP Vanilloid 1 and TRP Ankyrin repeat domain 1 (TRPV1 and TRPA1) are nocisensors playing important role to signal pain. Two "melastatin" TRP receptors, like TRPM8 and TRPM3 are also expressed in a subgroup of primary sensory neurons. These channels serve as thermosensors with unique thermal sensitivity ranges and are activated also by several exogenous and endogenous chemical ligands inducing conformational changes from various allosteric ("multisteric") sites. We analysed the role of plasma membrane microdomains of lipid rafts on isolated trigeminal (TRG) neurons and TRPV1-expressing CHO cell line by measuring agonist-induced Ca2+ transients with ratiometric technique. Stimulation-evoked calcitonin gene related peptide (CGRP) release from sensory nerve endings of the isolated rat trachea by radioimmunoassay was also measured. Lipid rafts were disrupted by cleaving sphingomyelin (SM) with sphingomyelinase (SMase), cholesterol depletion with methyl β-cyclodextrin (MCD) and ganglioside breakdown with myriocin. It has been revealed that intracellular Ca2+ increase responses evoked by the TRPV1 agonist capsaicin, the TRPA1 agonsits allyl isothiocyanate (AITC) and formaldehyde as well as the TRPM8 activator icilin were inhibited after SMase, MCD and myriocin incubation but the response to the TRPM3 agonist pregnenolon sulphate was not altered. Extracellular SMase treatment did not influence the thapsigargin-evoked Ca2+-release from intracellular stores. Besides the cell bodies, SMase also inhibited capsaicin- or AITC-evoked CGRP release from peripheral sensory nerve terminals, this provides the first evidence for the importance of lipid raft integrity in TRPV1 and TRPA1 gating on capsaicin-sensitive nerve terminals. SM metabolites, ceramide and sphingosine, did not influence TRPA1 and TRPV1 activation on TRG neurons, TRPV1-expressing CHO cell line, and nerve terminals. We suggest, that the hydrophobic

  4. What Are Nerve Blocks for Headache?

    MedlinePlus

    ... at the Montefiore Headache Center, Department of Neurology, Albert Einstein College of Medicine, Bronx, NY. Matthew S. Robbins, MD, ... is an assistant professor of neurology at the Albert Einstein College of Medicine, and the current chair of ...

  5. Neuromuscular block

    PubMed Central

    Bowman, W C

    2006-01-01

    Descriptions of the South American arrow poisons known as curares were reported by explorers in the 16th century, and their site of action in producing neuromuscular block was determined by Claude Bernard in the mid-19th century. Tubocurarine, the most important curare alkaloid, played a large part in experiments to determine the role of acetylcholine in neuromuscular transmission, but it was not until after 1943 that neuromuscular blocking drugs became established as muscle relaxants for use during surgical anaesthesia. Tubocurarine causes a number of unwanted effects, and there have been many attempts to replace it. The available drugs fall into two main categories: the depolarising blocking drugs and the nondepolarising blocking drugs. The former act by complex mixed actions and are now obsolete with the exception of suxamethonium, the rapid onset and brief duration of action of which remain useful for intubation at the start of surgical anaesthesia. The nondepolarising blocking drugs are reversible acetylcholine receptor antagonists. The main ones are the atracurium group, which possess a built-in self-destruct mechanism that makes them especially useful in kidney or liver failure, and the vecuronium group, which are especially free from unwanted side effects. Of this latter group, the compound rocuronium is of especial interest because its rapid onset of action allows it to be used for intubation, and there is promise that its duration of action may be rapidly terminated by a novel antagonist, a particular cyclodextrin, that chelates the drug, thereby removing it from the acetylcholine receptors. PMID:16402115

  6. Gabapentin loses efficacy over time after nerve injury in rats: role of glutamate transporter-1 in the locus coeruleus.

    PubMed

    Kimura, Masafumi; Eisenach, James C; Hayashida, Ken-Ichiro

    2016-09-01

    Despite being one of the first-choice analgesics for chronic neuropathic pain, gabapentin sometimes fails to provide analgesia, but the mechanisms for this lack of efficacy is unclear. Rats with nerve injury including L5-L6 spinal nerve ligation (SNL) respond uniformly and well to gabapentin, but many of these studies are performed within just a few weeks of injury, questioning their relevance to chronic neuropathic pain. In this study, intraperitoneal gabapentin showed a time-dependently reduction in antihypersensitivity after SNL, associated with downregulation of astroglial glutamate transporter-1 (GLT-1) in the locus coeruleus (LC). Consistently, SNL also time-dependently increased basal but masked gabapentin-induced noradrenergic neuronal activity in the LC. In rats 2 weeks after SNL, knock-down of GLT-1 in the LC reduced the antihypersensitivity effect of gabapentin. In rats 8 weeks after SNL, increasing GLT-1 expression by histone deacetylase inhibitor valproate restored the antihypersensitivity effect of gabapentin, associated with restored gabapentin-induced noradrenergic neuronal activity in the LC and subsequent spinal noradrenaline release. Knock-down of GLT-1 in the LC reversed the effect of valproate to restore gabapentin-induced antihypersensitivity. In addition, the antihypersensitivity effect of the intrathecal α2-adrenoceptor agonist clonidine also decreased with time after SNL injury. These results suggest that downregulation of GLT-1 in the LC and reduced spinal noradrenergic inhibition contribute to impaired analgesic efficacy from gabapentin in chronic neuropathic pain and that valproate can rescue this impaired efficacy.

  7. Silencing the α2 subunit of GABAA receptors in rat dorsal root ganglia reveals its major role in antinociception post-traumatic nerve injury

    PubMed Central

    Obradović, Aleksandar LJ; Scarpa, Joseph; Osuru, Hari P; Weaver, Janelle L; Park, Ji-Yong; Pathirathna, Sriyani; Peterkin, Alexander; Lim, Yunhee; Jagodic, Miljenko M; Todorovic, Slobodan M; Jevtovic-Todorovic, Vesna

    2015-01-01

    Background Neuropathic pain is likely the result of repetitive high frequency bursts of peripheral afferent activity leading to long-lasting changes in synaptic plasticity in the spinal dorsal horn (DH). Drugs that promote GABA activity in the DH provide partial relief of neuropathic symptoms. We examined how in vivo silencing of the GABAA α2 gene in DRG controls of NPP. Methods After crush injury to the right sciatic nerve of female rats, the α2 GABAA antisense and mismatch oligodeoxynucleotides or NO-711 (a GABA uptake inhibitor) were applied to the L5 DRG. In vivo behavioral assessment of nociception was conducted prior to the injury and ensuing 10 days (n=4–10). In vitro quantification of α2 GABAA protein and electrophysiology studies of GABAA currents were performed on acutely dissociated L5 DRG neurons at relevant time-points (n=6–14). Results NPP post-crush injury of a sciatic nerve in adult female rats coincides with significant down-regulation of the α2 subunit expression in the ipsilateral DRG (about 30%). Selective down-regulation of α2 expression in DRGs significantly worsens mechanical (2.55±0.75 to 5.16±1.16) and thermal (7.97±0.96 to 5.51±0.75) hypersensitivity in crush-injured animals and causes development of significant mechanical (2.33±0.40 to 5.00±0.33) and thermal (10.80±0.29 to 7.34±0.81) hypersensitivity in sham animals (data shown as MEAN±SD). Conversely, up-regulation of endogenous GABA via blockade of its uptake in DRG alleviates NPP. Conclusions The GABAA receptor in the DRG plays an important role in pathophysiology of NPP caused by sciatic nerve injury and represent promising target for novel pain therapies. PMID:26164299

  8. Role of Liquid-based Cytology and Cell Block in the Diagnosis of Endometrial Lesions

    PubMed Central

    Zhang, Hui; Wen, Jia; Xu, Pi-Li; Chen, Rui; Yang, Xi; Zhou, Lian-Er; Jiang, Ping; Wan, An-Xia; Liao, Qin-Ping

    2016-01-01

    Background: Liquid-based cytology (LBC) offers an alternative method to biopsy in screening endometrial cancer. Cell block (CB), prepared by collecting residual cytological specimen, represents a novel method to supplement the diagnosis of endometrial cytology. This study aimed to compare the specimen adequacy and diagnostic accuracy of LBC and CB in the diagnosis of endometrial lesions. Methods: A total of 198 women with high risks of endometrial carcinoma (EC) from May 2014 to April 2015 were enrolled in this study. The cytological specimens were collected by the endometrial sampler (SAP-1) followed by histopathologic evaluation of dilatation and curettage or biopsy guided by hysteroscopy. The residual cytological specimens were processed into paraffin-embedded CB after LBC preparation. Diagnostic accuracies of LBC and CB for detecting endometrial lesions were correlated with histological diagnoses. Chi-square test was used to compare the specimen adequacies of LBC and CB. Results: The specimen inadequate rate of CB was significantly higher than that of LBC (22.2% versus 7.1%, P < 0.01). There were 144 cases with adequate specimens for LBC and CB preparation. Among them, 29 cases were atypical endometrial hyperplasia (11 cases) or carcinoma (18 cases) confirmed by histology evaluation. Taking atypical hyperplasia and carcinoma as positive, the diagnostic accuracy of CB was 95.1% while it was 93.8% in LBC. When combined LBC with CB, the diagnostic accuracy was improved to 95.8%, with a sensitivity of 89.7% and specificity of 97.4%. Conclusions: CB is a feasible and reproducible adjuvant method for screening endometrial lesions. A combination of CB and LBC can improve the diagnostic accuracy of endometrial lesions. PMID:27270542

  9. On the role of block copolymer additives for calcium carbonate crystallization: small angle neutron scattering investigation by applying contrast variation.

    PubMed

    Endo, Hitoshi; Schwahn, Dietmar; Cölfen, Helmut

    2004-05-15

    The role of the double-hydrophilic block copolymer poly(ethylen glycol)-block-poly(methacrylic acid) (PEG-b-PMAA) on the morphogenesis of calcium carbonate (CaCO3) was studied by applying the contrast variation small angle neutron scattering technique. The morphology and size of CaCO3 crystals is strongly affected by the addition of PEG-b-PMAA. In order to determine the partial scattering functions of the polymer and CaCO3 mineral, we developed both an experimental and theoretical approach with a sophisticated method of their determination from the scattering intensity. Partial scattering functions give detailed information for each component. In particular, the partial scattering function of the polymer, Spp, shows a monotonic slope with Q(-2 to -3) where the scattering vector Q is low (Q < 0.01 Angstrom(-1)), which is a clear evidence that the polymer within the CaCO3 mineral has a mass fractal dimension. The other partial scattering functions reflected the geometry of the CaCO3 particles or the "interaction" of polymer and CaCO3 on a microscopic scale, which leads to a coherent view with Spp.

  10. A Historical Perspective on the Role of Functional Lines of Block in the Re-entrant Circuit of Ventricular Tachycardia.

    PubMed

    Proietti, Riccardo; Roux, Jean-Francois; Verma, Atul; Alturki, Ahmed; Bernier, Martin L; Essebag, Vidal

    2016-05-01

    The ablation strategy for ventricular tachycardia (VT) rapidly evolved from an entrainment mapping approach for identification of the critical isthmus of the re-entrant circuit during monomorphic VT, toward a substrate-based approach aiming to ablate surrogate markers of the circuit during sinus rhythm in hemodynamically nontolerated and polymorphic VT. The latter approach implies an assumption that the circuits responsible for the arrhythmia are anatomical or fixed, and present during sinus rhythm. Accordingly, the lines of block delimiting the channels of the circuits are often considered fixed, although there is evidence that they are functional or more frequently a combination of fixed and functional. The electroanatomical substrate-based approach to VT ablation performed during sinus rhythm is increasingly adopted in clinical practice and often described as scar homogenization, scar dechanneling, or core isolation. However, whether the surrogate markers of the VT circuit during sinus rhythm match the circuit during arrhythmias remains to be fully demonstrated. The myocardial scar is a heterogeneous electrophysiological milieu with complex arrhythmogenic mechanisms that potentially coexist simultaneously. Moreover, the scar consists of different areas of diverse refractoriness and conduction. It can be misleading to limit the arrhythmogenic perspective of the myocardial scar to fixed or anatomical barriers held responsible for the re-entry circuit. Greater understanding of the role of functional lines of block in VT and the validity of the surrogate targets being ablated is necessary to further improve the technique and outcome of VT ablation.

  11. The role of the vagus nerve in the migrating motor complex and ghrelin- and motilin-induced gastric contraction in suncus.

    PubMed

    Miyano, Yuki; Sakata, Ichiro; Kuroda, Kayuri; Aizawa, Sayaka; Tanaka, Toru; Jogahara, Takamichi; Kurotani, Reiko; Sakai, Takafumi

    2013-01-01

    The upper gastrointestinal (GI) tract undergoes a temporally coordinated cyclic motor pattern known as the migrating motor complex (MMC) in both dogs and humans during the fasted state. Feeding results in replacement of the MMC by a pattern of noncyclic, intermittent contractile activity termed as postprandial contractions. Although the MMC is known to be stimulated by motilin, recent studies have shown that ghrelin, which is from the same peptide family as motilin, is also involved in the regulation of the MMC. In the present study, we investigated the role of the vagus nerve on gastric motility using conscious suncus-a motilin- and ghrelin-producing small animal. During the fasted state, cyclic MMC comprising phases I, II, and III was observed in both sham-operated and vagotomized suncus; however, the duration and motility index (MI) of phase II was significantly decreased in vagotomized animals. Motilin infusion (50 ng·kg(-1)·min(-1) for 10 min) during phase I had induced phase III-like contractions in both sham-operated and vagotomized animals. Ghrelin infusion (0.1, 0.3, 1, 3, or 10 µg·kg(-1)·min(-1) for 10 min) enhanced the amplitude of phase II MMC in sham-operated animals, but not in vagotomized animals. After feeding, phase I was replaced by postprandial contractions, and motilin infusion (50 ng·kg(-1)·min(-1) for 10 min) did not induce phase III-like contractions in sham-operated suncus. However, in vagotomized suncus, feeding did not evoke postprandial contractions, but exogenous motilin injection strongly induced phase III-like contractions, as noted during the phase I period. Thus, the results indicate that ghrelin stimulates phase II of the MMC via the vagus nerve in suncus. Furthermore, the vagus nerve is essential for initiating postprandial contractions, and inhibition of the phase III-like contractions induced by motilin is highly dependent on the vagus nerve. PMID:23724093

  12. Cocontinuous polymer blends: The role of block copolymer in blend morphology evolution

    NASA Astrophysics Data System (ADS)

    Bell, Joel Richard

    Cocontinuous morphologies are distinguished by the mutual interpenetration of two polymer phases and allow for enhanced mechanical properties, static charge dissipation, and barrier properties. Cocontinuous morphologies form over a range of compositions, depending largely on mixing history and the relative polymer viscosities, elasticities, and interfacial tension. Because cocontinuous morphologies are thermodynamically unstable, they will coarsen when held above their glass or melt transition temperature. Since the unique properties of these blends depend directly on the continuous nature of the microstructure and its phase size, stabilization of the cocontinuous morphology is extremely important. To address this challenge, compatibilizers, e.g. block copolymers (bcp), are often added to hinder phase coarsening in blends of immiscible polymers and can improve bonding at interfaces. The effects of bcp on the cocontinuous morphology of polystyrene (PS)/polyethylene (PE) and PS/poly(methyl methacrylate) (PMMA) blends were studied using scanning electron microscopy (SEM) with image analysis, 3D imaging, mercury porosimetry, solvent extraction, and rheology. It was shown that diblock copolymers were able to suppress coarsening during annealing in cocontinuous PS/PE and PS/PMMA blends. Bcp effectiveness was dependent on molecular weight, concentration, and architecture. Self consistent mean field theory and bending elasticity theory were used to estimate the proper bcp architecture for maximum reduction in interfacial tension; experimental results agreed well with the theory. In addition to slowing coarsening, bcp was shown to widen the range of cocontinuity for both the PS/PE and PS/PMMA systems. To aid determination of the range of cocontinuity, a new technique for analyzing SEM micrographs was developed. The new technique classifies blend morphology according to the normalized fraction of drops present in the 2D microstructure. It was found that a blend becomes

  13. Intrinsic Electrostatic Potential in the BK Channel Pore: Role in Determining Single Channel Conductance and Block

    PubMed Central

    Carvacho, Ingrid; Gonzalez, Wendy; Torres, Yolima P.; Brauchi, Sebastian; Alvarez, Osvaldo; Gonzalez-Nilo, Fernando D.; Latorre, Ramon

    2008-01-01

    The internal vestibule of large-conductance Ca2+ voltage-activated K+ (BK) channels contains a ring of eight negative charges not present in K+ channels of lower conductance (Glu386 and Glu389 in hSlo) that modulates channel conductance through an electrostatic mechanism (Brelidze, T.I., X. Niu, and K.L. Magleby. 2003. Proc. Natl. Acad. Sci. USA. 100:9017–9022). In BK channels there are also two acidic amino acid residues in an extracellular loop (Asp326 and Glu329 in hSlo). To determine the electrostatic influence of these charges on channel conductance, we expressed wild-type BK channels and mutants E386N/E389N, D326N, E329Q, and D326N/E329Q channels on Xenopus laevis oocytes, and measured the expressed currents under patch clamp. Contribution of E329 to the conductance is negligible and single channel conductance of D326N/E329Q channels measured at 0 mV in symmetrical 110 mM K+ was 18% lower than the control. Current–voltage curves displayed weak outward rectification for D326N and the double mutant. The conductance differences between the mutants and wild-type BK were caused by an electrostatic effect since they were enhanced at low K+ (30 mM) and vanished at high K+ (1 M K+). We determine the electrostatic potential change, Δφ, caused by the charge neutralization using TEA+ block for the extracellular charges and Ba2+ for intracellular charges. We measured 13 ± 2 mV for Δφ at the TEA+ site when turning off the extracellular charges, and 17 ± 2 mV for the Δφ at the Ba2+ site when the intracellular charges were turned off. To understand the electrostatic effect of charge neutralizations, we determined Δφ using a BK channel molecular model embedded in a lipid bilayer and solving the Poisson-Boltzmann equation. The model explains the experimental results adequately and, in particular, gives an economical explanation to the differential effect on the conductance of the neutralization of charges D326 and E329. PMID:18227273

  14. Role of selective blocking of bradykinin receptor subtypes in attenuating allergic airway inflammation in guinea pigs.

    PubMed

    El-Kady, Mohamed M; Girgis, Zarif I; Abd El-Rasheed, Eman A; Shaker, Olfat; Attallah, Magdy I; Soliman, Ahmed A

    2016-10-01

    The present study was designed to evaluate the potential role of bradykinin antagonists (R-715; bradykinin B1 receptor antagonist and icatibant; bradykinin B2 receptor antagonist) in treatment of allergic airway inflammation in comparison to dexamethasone and montelukast. R-715 as dexamethasone significantly decreased peribronchial leukocyte infiltration, bronchoalveolar lavage fluid (BALF) albumin and interleukin 1β as well as serum OVA-specific IgE level. Also, R-715 like montelukast significantly decreased BALF cell count (total and eosinophils). Icatibant showed negative results. The current findings suggest that selective bradykinin B1 receptor antagonists may have the therapeutic potential for the treatment of allergic airway inflammation. PMID:27321873

  15. The cholinergic blocking action of adrenergic blocking agents in the pharmacological analysis of autonomic innervation

    PubMed Central

    Boyd, Helen; Burnstock, G.; Campbell, G.; Jowett, Alison; O'Shea, Judith; Wood, Margaret

    1963-01-01

    The adrenergic blocking agents tolazoline, phentolamine, piperoxan, yohimbine, phenoxybenzamine, bretylium and guanethidine block the excitatory actions both of cholinergic nerves and of added acetylcholine on a variety of vertebrate smooth muscle preparations. These cholinergic blocking actions often occurred with concentrations lower than those required to block the response of the guinea-pig vas deferens to stimulation of the adrenergic hypogastric nerve. The anti-acetylcholine activities of these drugs have been studied in detail, using the guinea-pig rectum and the toad bladder as test organs. In preparations sensitive to eserine, the anticholinesterase actions of the drugs competed with their anti-acetylcholine actions, so that either potentiation or block of responses to acetylcholine and to cholinergic nerve stimulation occurred with different concentrations. The responses of the toad bladder to acetylcholine were not potentiated by eserine. This enabled the antagonism of acetylcholine by the anti-adrenergic drugs to be estimated without interference from their anticholinesterase activity. When blocking activity was assessed on guinea-pig rectum previously treated with dyflos, the results were qualitatively similar to those on the toad bladder. Phenoxybenzamine often completely blocks responses both to added acetylcholine and to cholinergic nerve stimulation in concentrations less than those required to block adrenergic nerves. Guanethidine and piperoxan also show strong cholinergic blocking activity. Bretylium, yohimbine, tolazoline and phentolamine were less potent. However, in concentrations required to block the effect on the vas deferens of hypogastric nerve stimulation, these drugs at least halved the effects of acetylcholine and often of cholinergic nerve stimulation. It is concluded that these adrenergic blocking agents cannot be used to distinguish conclusively between adrenergic and cholinergic nerves. For reliable analysis of autonomic

  16. Exogenous nerve growth factor protects the hypoglossal nerve against crush injury

    PubMed Central

    Fan, Li-yuan; Wang, Zhong-chao; Wang, Pin; Lan, Yu-yan; Tu, Ling

    2015-01-01

    Studies have shown that sensory nerve damage can activate the p38 mitogen-activated protein kinase (MAPK) pathway, but whether the same type of nerve injury after exercise activates the p38MAPK pathway remains unclear. Several studies have demonstrated that nerve growth factor may play a role in the repair process after peripheral nerve injury, but there has been little research focusing on the hypoglossal nerve injury and repair. In this study, we designed and established rat models of hypoglossal nerve crush injury and gave intraperitoneal injections of exogenous nerve growth factor to rats for 14 days. p38MAPK activity in the damaged neurons was increased following hypoglossal nerve crush injury; exogenous nerve growth factor inhibited this increase in acitivity and increased the survival rate of motor neurons within the hypoglossal nucleus. Under transmission electron microscopy, we found that the injection of nerve growth factor contributed to the restoration of the morphology of hypoglossal nerve after crush injury. Our experimental findings indicate that exogenous nerve growth factor can protect damaged neurons and promote hypoglossal nerve regeneration following hypoglossal nerve crush injury. PMID:26889186

  17. Improved technique for CT-guided celiac ganglia block

    SciTech Connect

    Haaga, J.R.; Kori, S.H.; Eastwood, D.W.; Borowski, G.P.

    1984-06-01

    Celiac nerve blocks have been performed without radiologic guidance, but recently several groups have reported computed tomography (CT)-guided techniques. The authors present a new technique of CT-guided celiac nerve block using an 18 gauge Teflon catheter, which permits a test block dose and permanent alcohol block with one procedure. The results of this new technique were very encouraging. Of nine cancer patients who had the test block, seven had good pain relief; these same patients had good pain control with the permanent block. Of six patients with pancreatitis, six had good pain relief from the test block, and three had some long-term relief from the permanent block.

  18. Heart Block

    MedlinePlus

    ... Block Explore Heart Block What Is... Electrical System & EKG Results Types Causes Who Is at Risk Signs & ... heart block. Doctors use a test called an EKG (electrocardiogram) to help diagnose heart block. This test ...

  19. Genomic and molecular aberrations in malignant peripheral nerve sheath tumor and their roles in personalized target therapy.

    PubMed

    Yang, Jilong; Du, Xiaoling

    2013-09-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are malignant tumors with a high rate of local recurrence and a significant tendency to metastasize. Its dismal outcome points to the urgent need to establish better therapeutic strategies for patients harboring MPNSTs. The investigations of genomic and molecular aberrations in MPNSTs which detect many chromosomal aberrations, pathway abnormalities, and specific molecular aberrant events would supply multiple potential therapy targets and contribute to achievement of personalized medicine. The involved genes in the significant gains aberrations include BIRC5, CCNE2, DAB2, DDX15, EGFR, DAB2, MSH2, CDK6, HGF, ITGB4, KCNK12, LAMA3, LOXL2, MET, and PDGFRA. The involved genes in the significant deletion aberrations include CDH1, GLTSCR2, EGR1, CTSB, GATA3, SULT2A1, GLTSCR2, HMMR/RHAMM, LICAM2, MMP13, p16/INK4a, RASSF2, NM-23H1, and TP53. These genetic aberrations involve in several important signaling pathways such as TFF, EGFR, ARF, IGF1R signaling pathways. The genomic and molecular aberrations of EGFR, IGF1R, SOX9, EYA4, TOP2A, ETV4, and BIRC5 exhibit great promise as personalized therapeutic targets for MPNST patients. PMID:23830351

  20. Hypertonic enhancement of transmitter release from frog motor nerve terminals: Ca2+ independence and role of integrins

    NASA Technical Reports Server (NTRS)

    Kashani, A. H.; Chen, B. M.; Grinnell, A. D.

    2001-01-01

    Hyperosmotic solutions cause markedly enhanced spontaneous quantal release of neurotransmitter from many nerve terminals. The mechanism of this enhancement is unknown. We have investigated this phenomenon at the frog neuromuscular junction with the aim of determining the degree to which it resembles the modulation of release by stretch, which has been shown to be mediated by mechanical tension on integrins.The hypertonicity enhancement, like the stretch effect, does not require Ca2+ influx or release from internal stores, although internal release may contribute to the effect. The hypertonicity effect is sharply reduced (but not eliminated) by peptides containing the RGD sequence, which compete with native ligands for integrin bonds.There is co-variance in the magnitude of the stretch and osmotic effects; that is, individual terminals exhibiting a large stretch effect also show strong enhancement by hypertonicity, and vice versa. The stretch and osmotic enhancements also can partially occlude each other.There remain some clear-cut differences between osmotic and stretch forms of modulation: the larger range of enhancement by hypertonic solutions, the relative lack of effect of osmolarity on evoked release, and the reported higher temperature sensitivity of osmotic enhancement. Nevertheless, our data strongly implicate integrins in a significant fraction of the osmotic enhancement, possibly acting via the same mechanism as stretch modulation.

  1. Role of the Internal Superior Laryngeal Nerve in the Motor Responses of Vocal Cords and the Related Voice Acoustic Changes

    PubMed Central

    Seifpanahi, Sadegh; Izadi, Farzad; Jamshidi, Ali-Ashraf; Torabinezhad, Farhad; Sarrafzadeh, Javad; Mohammadi, Siavash

    2016-01-01

    Background: Repeated efforts by researchers to impose voice changes by laryngeal surface electrical stimulation (SES) have come to no avail. This present pre-experimental study employed a novel method for SES application so as to evoke the motor potential of the internal superior laryngeal nerve (ISLN) and create voice changes. Methods: Thirty-two normal individuals (22 females and 10 males) participated in this study. The subjects were selected from the students of Iran University of Medical Sciences in 2014. Two monopolar active electrodes were placed on the thyrohyoid space at the location of the ISLN entrance to the larynx and 1 dispersive electrode was positioned on the back of the neck. A current with special programmed parameters was applied to stimulate the ISLN via the active electrodes and simultaneously the resultant acoustic changes were evaluated. All the means of the acoustic parameters during SES and rest periods were compared using the paired t-test. Results: The findings indicated significant changes (P=0.00) in most of the acoustic parameters during SES presentation compared to them at rest. The mean of fundamental frequency standard deviation (SD F0) at rest was 1.54 (SD=0.55) versus 4.15 (SD=3.00) for the SES period. The other investigated parameters comprised fundamental frequency (F0), minimum F0, jitter, shimmer, harmonic-to-noise ratio (HNR), mean intensity, and minimum intensity. Conclusion: These findings demonstrated significant changes in most of the important acoustic features, suggesting that the stimulation of the ISLN via SES could induce motor changes in the vocal folds. The clinical applicability of the method utilized in the current study in patients with vocal fold paralysis requires further research. PMID:27582586

  2. The role of cyclic AMP and its protein kinase in mediating acetylcholine release and the action of adenosine at frog motor nerve endings.

    PubMed Central

    Hirsh, J. K.; Silinsky, E. M.; Solsona, C. S.

    1990-01-01

    1. The importance of adenosine 3':5'-cyclic monophosphate (cyclic AMP) and its protein kinase (protein kinase A, PKA) in promoting acetylcholine (ACh) release was studied at frog motor nerve endings. The effects of cyclic AMP-dependent protein phosphorylation on the action of adenosine receptor agonists were also investigated. 2. Cyclic AMP was delivered to a local region of the cytoplasm just beneath the plasma membrane of motor nerve endings using phospholipid vesicles (liposomes) as a vehicle. Cyclic AMP in liposomes produced a parallel reduction in the mean level of evoked ACh release (m) and spontaneous ACh release (miniature endplate potential frequency; m.e.p.p.f) in most experiments. These inhibitory effects of cyclic AMP on quantal ACh release resemble the action of adenosine. 3. The effects of global increases in cytoplasmic cyclic AMP concentrations using lipophilic cyclic AMP analogues were generally different from those observed with cyclic AMP. 8-(4-Chlorophenylthio) cyclic AMP (CPT cyclic AMP) produced approximately two fold increases in m and m.e.p.p.f. Dibutyryl cyclic AMP (db cyclic AMP) also increased m and m.e.p.p.f, with the effect on m being smaller and more variable. 4. All three cyclic AMP analogues reduced the effects of adenosine receptor agonists on spontaneous and evoked ACh release. 5. The roles of protein phosphorylation in mediating ACh release and the inhibitory effects of adenosine were studied with the protein kinase inhibitor H7. H7 (30-100 microM) produced no consistent effect on evoked or spontaneous ACh release. At these concentrations, however, H7 exerted an unfortunate inhibitory action on the nicotinic ACh receptor/ion channel.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2175231

  3. Role of brainstem serotonin in analgesia produced by low-intensity exercise on neuropathic pain after sciatic nerve injury in mice.

    PubMed

    Bobinski, Franciane; Ferreira, Tamara A A; Córdova, Marina M; Dombrowski, Patrícia A; da Cunha, Cláudio; Santo, Caroline C do Espírito; Poli, Anicleto; Pires, Rita G W; Martins-Silva, Cristina; Sluka, Kathleen A; Santos, Adair R S

    2015-12-01

    Physical exercise is a low-cost, safe, and efficient intervention for the reduction of neuropathic chronic pain in humans. However, the underlying mechanisms for how exercise reduces neuropathic pain are not yet well understood. Central monoaminergic systems play a critical role in endogenous analgesia leading us to hypothesize that the analgesic effect of low-intensity exercise occurs through activation of monoaminergic neurotransmission in descending inhibitory systems. To test this hypothesis, we induced peripheral nerve injury (PNI) by crushing the sciatic nerve. The exercise intervention consisted of low-intensity treadmill running for 2 weeks immediately after injury. Animals with PNI showed an increase in pain-like behaviors that were reduced by treadmill running. Reduction of serotonin (5-hydroxytryptamine) synthesis using the tryptophan hydroxylase inhibitor para-chlorophenylalanine methyl ester prevented the analgesic effect of exercise. However, blockade catecholamine synthesis with the tyrosine hydroxylase inhibitor alpha-methyl-para-tyrosine had no effect. In parallel, 2 weeks of exercise increased brainstem levels of the 5-HT and its metabolites (5-hydroxyindoleacetic acid), decreased expression of the serotonin transporter, and increased expression of 5-HT receptors (5HT-1B, 2A, 2C). Finally, PNI-induced increase in inflammatory cytokines, tumor necrosis factor-alpha, and interleukin-1 beta, in the brainstem, was reversed by 2 weeks of exercise. These findings provide new evidence indicating that low-intensity aerobic treadmill exercise suppresses pain-like behaviors in animals with neuropathic pain by enhancing brainstem 5-HT neurotransmission. These data provide a rationale for the analgesia produced by exercise to provide an alternative approach to the treatment of chronic neuropathic pain.

  4. Nerve Impulses in Plants

    ERIC Educational Resources Information Center

    Blatt, F. J.

    1974-01-01

    Summarizes research done on the resting and action potential of nerve impulses, electrical excitation of nerve cells, electrical properties of Nitella, and temperature effects on action potential. (GS)

  5. Profiling of dynamically changed gene expression in dorsal root ganglia post peripheral nerve injury and a critical role of injury-induced glial fibrillary acidic protein in maintenance of pain behaviors [corrected].

    PubMed

    Kim, Doo-Sik; Figueroa, Katherine W; Li, Kang-Wu; Boroujerdi, Amin; Yolo, Tim; Luo, Z David

    2009-05-01

    To explore cellular changes in sensory neurons after nerve injury and to identify potential target genes contributing to different stages of neuropathic pain development, we used Affymetrix oligo arrays to profile gene expression patterns in L5/6 dorsal root ganglia (DRG) from the neuropathic pain model of left L5/6 spinal nerve ligation at different stages of neuropathic pain development. Our data indicated that nerve injury induced changes in expression of genes with similar biological functions in a temporal specific manner that correlates with particular stages of neuropathic pain development, indicating dynamic neuroplasticity in the DRG in response to peripheral nerve injury and during neuropathic pain development. Data from post-array validation indicated that there was a temporal correlation between injury-induced expression of the glial fibrillary acidic protein (GFAP), a marker for activated astrocytes, and neuropathic pain development. Spinal nerve ligation injury in GFAP knockout mice resulted in neuropathic pain states with similar onset, but a shortened duration compared with that in age, and gender-matched wild-type littermates. Intrathecal GFAP antisense oligonucleotide treatment in injured rats with neuropathic pain states reversed injury-induced behavioral hypersensitivity and GFAP upregulation in DRG and spinal cord. Together, these findings indicate that injury-induced GFAP upregulation not only serves as a marker for astrocyte activation, but it may also play a critical, but yet identified, role in the maintenance of neuropathic pain states. PMID:19307059

  6. Peripheral nerve hyperexcitability syndromes.

    PubMed

    Küçükali, Cem Ismail; Kürtüncü, Murat; Akçay, Halil İbrahim; Tüzün, Erdem; Öge, Ali Emre

    2015-01-01

    Peripheral nerve hyperexcitability (PNH) syndromes can be subclassified as primary and secondary. The main primary PNH syndromes are neuromyotonia, cramp-fasciculation syndrome (CFS), and Morvan's syndrome, which cause widespread symptoms and signs without the association of an evident peripheral nerve disease. Their major symptoms are muscle twitching and stiffness, which differ only in severity between neuromyotonia and CFS. Cramps, pseudomyotonia, hyperhidrosis, and some other autonomic abnormalities, as well as mild positive sensory phenomena, can be seen in several patients. Symptoms reflecting the involvement of the central nervous system occur in Morvan's syndrome. Secondary PNH syndromes are generally seen in patients with focal or diffuse diseases affecting the peripheral nervous system. The PNH-related symptoms and signs are generally found incidentally during clinical or electrodiagnostic examinations. The electrophysiological findings that are very useful in the diagnosis of PNH are myokymic and neuromyotonic discharges in needle electromyography along with some additional indicators of increased nerve fiber excitability. Based on clinicopathological and etiological associations, PNH syndromes can also be classified as immune mediated, genetic, and those caused by other miscellaneous factors. There has been an increasing awareness on the role of voltage-gated potassium channel complex autoimmunity in primary PNH pathogenesis. Then again, a long list of toxic compounds and genetic factors has also been implicated in development of PNH. The management of primary PNH syndromes comprises symptomatic treatment with anticonvulsant drugs, immune modulation if necessary, and treatment of possible associated dysimmune and/or malignant conditions. PMID:25719304

  7. Peripheral nerve injuries in the athlete.

    PubMed

    Feinberg, J H; Nadler, S F; Krivickas, L S

    1997-12-01

    Peripheral nerves are susceptible to injury in the athlete because of the excessive physiological demands that are made on both the neurological structures and the soft tissues that protect them. The common mechanisms of injury are compression, traction, ischaemia and laceration. Seddon's original classification system for nerve injuries based on neurophysiological changes is the most widely used. Grade 1 nerve injury is a neuropraxic condition, grade 2 is axonal degeneration and grade 3 is nerve transection. Peripheral nerve injuries are more common in the upper extremities than the lower extremities, tend to be sport specific, and often have a biomechanical component. While the more acute and catastrophic neurological injuries are usually obvious, many remain subclinical and are not recognised before neurological damage is permanent. Early detection allows initiation of a proper rehabilitation programme and modification of biomechanics before the nerve injury becomes irreversible. Recognition of nerve injuries requires an understanding of peripheral neuroanatomy, knowledge of common sites of nerve injury and an awareness of the types of peripheral nerve injuries that are common and unique to each sport. The electrodiagnostic exam, usually referred to as the 'EMG', consists of nerve conduction studies and the needle electrode examination. It is used to determine the site and degree of neurological injury and to predict outcome. It should be performed by a neurologist or physiatrist (physician specialising in physical medicine and rehabilitation), trained and skilled in this procedure. Timing is essential if the study is to provide maximal information. Findings such as decreased recruitment after injury and conduction block at the site of injury may be apparent immediately after injury but other findings such as abnormal spontaneous activity may take several weeks to develop. The electrodiagnostic test assists with both diagnosis of the injury and in predicting

  8. Secondary optic nerve tumors.

    PubMed

    Christmas, N J; Mead, M D; Richardson, E P; Albert, D M

    1991-01-01

    Secondary tumors of the optic nerve are more common than primary optic nerve tumors. The involvement of the optic nerve may arise from direct invasion from intraocular malignancies, from hematopoietic malignancy, from meningeal carcinomatosis, or from distant primary tumors. Orbital tumors rarely invade the optic nerve, and brain tumors involve it only in their late stages.

  9. Maternal anticonvulsants and optic nerve hypoplasia.

    PubMed Central

    Hoyt, C. S.; Billson, F. A.

    1978-01-01

    Seven patients with optic nerve hypoplasia, born of epileptic mothers, are presented. All the mothers took anticonvulsants during pregnancy. The possibility that maternal anticonvulsant therapy may play a role in the genesis of optic nerve hypoplasia is discussed in the light of what is known about the teratogenicity of these agents. Images PMID:415754

  10. Postoperative sciatic and femoral or saphenous nerve blockade for lower extremity surgery in anesthetized adults

    PubMed Central

    Lollo, Loreto; Bhananker, Sanjay; Stogicza, Agnes

    2015-01-01

    Background: Guidelines warn of increased risks of injury when placing regional nerve blocks in the anesthetized adult but complications occurred in patients that received neither sedation nor local anesthetic. This restriction of nerve block administration places vulnerable categories of patients at risk of severe opioid induced side effects. Patient and operative technical factors can preclude use of preoperative regional anesthesia. The purpose of this study was to assess complications following sciatic popliteal and femoral or saphenous nerve blockade administered to anesthetized adult patients following foot and ankle surgery. Materials and Methods: Postoperative patients administered general anesthesia received popliteal sciatic nerve blockade and either femoral or saphenous nerve blockade if operative procedures included medial incisions. Nerve blocks were placed with nerve stimulator or ultrasound guidance. A continuous nerve catheter was inserted if hospital admission was over 24 hours. Opioid analgesic supplementation was administered for inadequate pain relief. Postoperative pain scores and total analgesic requirements for 24 hours were recorded. Nerve block related complications were monitored for during the hospital admission and at follow up surgical clinic evaluation. Results: 190 anesthetized adult patients were administered 357 nerve blocks. No major nerve injury or deficit was reported. One patient had numbness in the toes not ascribed to a specific nerve of the lower extremity. Perioperative opioid dose differences were noted between male and female and between opioid naïve and tolerant patients. PMID:26807391

  11. Magnetic resonance imaging of optic nerve

    PubMed Central

    Gala, Foram

    2015-01-01

    Optic nerves are the second pair of cranial nerves and are unique as they represent an extension of the central nervous system. Apart from clinical and ophthalmoscopic evaluation, imaging, especially magnetic resonance imaging (MRI), plays an important role in the complete evaluation of optic nerve and the entire visual pathway. In this pictorial essay, the authors describe segmental anatomy of the optic nerve and review the imaging findings of various conditions affecting the optic nerves. MRI allows excellent depiction of the intricate anatomy of optic nerves due to its excellent soft tissue contrast without exposure to ionizing radiation, better delineation of the entire visual pathway, and accurate evaluation of associated intracranial pathologies. PMID:26752822

  12. Imaging the Facial Nerve: A Contemporary Review

    PubMed Central

    Gupta, Sachin; Mends, Francine; Hagiwara, Mari; Fatterpekar, Girish; Roehm, Pamela C.

    2013-01-01

    Imaging plays a critical role in the evaluation of a number of facial nerve disorders. The facial nerve has a complex anatomical course; thus, a thorough understanding of the course of the facial nerve is essential to localize the sites of pathology. Facial nerve dysfunction can occur from a variety of causes, which can often be identified on imaging. Computed tomography and magnetic resonance imaging are helpful for identifying bony facial canal and soft tissue abnormalities, respectively. Ultrasound of the facial nerve has been used to predict functional outcomes in patients with Bell's palsy. More recently, diffusion tensor tractography has appeared as a new modality which allows three-dimensional display of facial nerve fibers. PMID:23766904

  13. Characterization of serum resistance of Neisseria gonorrhoeae that disseminate. Roles of blocking antibody and gonococcal outer membrane proteins.

    PubMed

    Rice, P A; Kasper, D L

    1982-07-01

    Neisseria gonorrhoeae isolated from patients with disseminated infection (DGI) often resist complement (C')-dependent killing by normal human serum (NHS) and less commonly by convalescent DGI serum. 7 of 10 NHS specimens completely inhibited killing of serum-resistant (ser(r)) gonococci by convalescent or immune DGI serum. Immunoglobulin G (IgG) purified from NHS was shown to be the blocking agent. In addition, IgM (plus C') purified from NHS was shown to be fivefold more effective (wt/wt) in killing serum-sensitive (ser(s)) gonococci than equivalent amounts of IgM tested in the presence of IgG (whole serum). Although inhibition of NHS killing of ser(s) gonococci required a 640% excess of IgG, only a 40% excess was required to block immune serum killing of ser(r) gonococci. F(ab')(2) prepared from IgG also blocked killing of ser(r) gonococci by immune serum indicating antigenic specificity of blocking IgG.IgG immunoconcentrated against outer membrane protein (OMP) derived from ser(r) gonococci showed 40-fold increased blocking activity over normal IgG (wt/wt) and lacked antibody activity directed against gonococcal lipopolysaccharide by ELISA. Using direct immunoabsorption of IgG with purified gonococcal OMP; ser(r)-OMP was found sixfold more effective than ser(s)-OMP in neutralizing the blocking of immune serum killing of ser(r) gonococci, and 10-fold more effective in systems that used excess blocking IgG, NHS, and ser(s) gonococci. Blocking IgG preabsorbed with whole ser(r) gonococci lost 75% of its ability to block immune serum killing compared with no loss in this system using a similar absorption with ser(s) gonococci. IgG purified from NHS contained fivefold higher titers of antibody against ser(r)-OMP than ser(s)-OMP by ELISA.

  14. The role of regional nerve block anesthesia for carotid endarterectomy: an experimental comparison with previous series with the use of general anesthesia and barbiturates for cerebral protection.

    PubMed

    Agrifoglio, G; Agus, G B; Bonalumi, F; Costantini, A; Carlesi, R

    1987-01-01

    A retrospective analysis was performed on a consecutive series of 60 cases divided into two groups given carotid endarterectomy (C.E.) for atherosclerotic disease. In the first group general anesthesia and barbiturate cerebral protection were employed; in group two, loco-regional anesthesia. Indications and risk factors were similar in the two groups; the surgical procedure was identical. The differences in the results are reported and factors contributing to cerebral protection or reduction in the risk of stroke are analyzed. The analysis indicates that loco-regional anesthesia for C.E. is a reliable method for detecting cerebral ischemia and guaranteeing cerebral protection by means of a temporary shunt when strictly necessary. PMID:3450753

  15. Endothelial dysfunction and increased responses to renal nerve stimulation in rat kidneys during rhabdomyolysis-induced acute renal failure: role of hydroxyl radical.

    PubMed

    Cil, Onur; Ertunc, Mert; Gucer, Kadri Safak; Ozaltin, Fatih; Iskit, Alper Bektas; Onur, Rustu

    2012-01-01

    Rhabdomyolysis is an important cause of acute renal failure (ARF) and renal vasoconstriction is the main mechanism in the pathogenesis of ARF. Lipid peroxidation due to hydroxyl radical (.OH) formation and redox cycling of myoglobin also have a role. We investigated the disturbance in renal vascular reactivity to reveal the mechanisms leading to ARF. Female Wistar rats (n = 7) were injected with glycerol (10 mL/kg, 50% in saline) intramuscularly to induce rhabdomyolysis, and then the kidneys were isolated and perfused. We investigated acetylcholine (ACh)-induced endothelium-dependent and papaverine (PAP)-induced endothelium-independent vasodilation responses and renal nerve stimulation (RNS)-induced vasoconstrictions. These were also investigated both in rats which received either .OH scavenger, dimethylthiourea (DMTU: 500 mg/kg before glycerol injection and 125 mg/kg 8 h after glycerol injection, n = 7), or myoglobin redox cycling inhibitor, acetaminophen (ApAP: 100 mg/kg 2 h before glycerol injection and 100 mg/kg each 4 h, and 22 h after glycerol injection, n = 7). ACh-induced responses in glycerol group were decreased (p < 0.001), but PAP-induced vasodilation did not change. RNS-induced vasoconstriction in all kidneys was greater (p < 0.001) in glycerol group. DMTU restored both endothelium-dependent vasodilation and RNS-induced vasoconstriction. ApAP had no effect on vascular responses. Both DMTU and ApAP exerted a partial protective effect in renal histology without restoring serum creatinine and blood urea nitrogen (BUN) levels or creatinine clearance. This study showed that endothelial dysfunction and increased vasoconstriction developed during rhabdomyolysis. .OH plays an important role in the development of these vascular responses. These findings suggest that decreased endothelium-dependent vasodilation and augmented renal sympathetic tonus contribute to the development of renal vasoconstriction during rhabdomyolysis-induced ARF.

  16. Lung dendritic cells undergo maturation and polarization towards a T helper type 2-stimulating phenotype in a mouse model of asthma: Role of nerve growth factor

    PubMed Central

    QIN, QINGWU; WANG, ZHAN; PAN, PINHUA; CAO, ZU; XIA, QING; TAN, HONGYI; HU, CHENGPING

    2014-01-01

    Nerve growth factor (NGF) and dendritic cells (DCs) have been hypothesized to modulate T cell responses in a mouse model of asthma. However, whether NGF plays a role in regulating the maturation and polarization of lung DCs remains unclear. In the present study, the effect of NGF inhibition on the maturation and phenotype of lung DCs was investigated in a mouse model of asthma. BALB/c mice were sensitized and challenged with ovalbumin (OVA), and subsequently received anti-NGF treatment. At 24 h following the last challenge, airway responsiveness and inflammation were examined. The concentrations of NGF, interferon (IFN)-γ and interleukin (IL)-4 were analyzed. In addition, maturation and CD103 expression in the lung DCs were investigated. Anti-NGF treatment was found to significantly reduce airway hyperreactivity and inflammation in asthmatic mice. In addition, a subdued T helper 2 (Th2) response was observed, characterized by the downregulation of IL-4 and the upregulation of IFN-γ. Furthermore, the expression of the DC surface molecules, CD80, CD86 and major histocompatibility complex class II, as well as the proportion of lung CD103+ DCs, decreased in the OVA-sensitized and challenged mice. The proportion of lung CD103+ DCs also exhibited a positive correlation with the levels of plasma NGF in the mice. These results may provide an explanation for the role of NGF in amplifying the Th2 response in allergic diseases. Therefore, NGF may promote the maturation and polarization towards a Th2-stimulating phenotype of activated DCs, contributing to an amplification of the Th2 response in asthma. PMID:25289030

  17. Nerve Injuries in Athletes.

    PubMed

    Collins, K; Storey, M; Peterson, K; Nutter, P

    1988-01-01

    In brief: Nerve injuries in athletes may be serious and may delay or prevent an athlete's return to his or her sport. Over a two-year period, the authors evaluated the condition of 65 patients who had entrapments of a nerve or nerve root, documented with electromyography. They describe four case histories: Two patients had radial nerve entrapments, one caused by baseball pitching and the other by kayaking; one football player had combined suprascapular neuropathy and upper trunk brachial plexopathy; and one patient had carpal tunnel syndrome of a median nerve secondary to rowing. Sports-related peripheral nerve lesions of the lower extremity were not seen during the study period. Based on a literature review, the nerve injuries discussed represent the spectrum of nerve entrapments likely to be seen in US clinics. The authors conclude that peripheral nerve lesions should be considered in the differential diagnosis of sports injuries, particularly at the shoulder, elbow, and wrist.

  18. UPPER AIRWAY BLOCKS FOR AWAKE DIFFICULT AIRWAY MANAGEMENT.

    PubMed

    Pintaric, Tatjana Stopar

    2016-03-01

    Airway anesthesia is pivotal for successful awake intubation provided either topically or by blocks. Airway blocks are considered technically more difficult to perform and carry a higher risk of complications. However, in experienced hands, they can be useful as they provide excellent intubating conditions. For complete upper airway anesthesia, bilateral glossopharyngeal and superior laryngeal nerve blocks with translaryngeal injection are required. Superior laryngeal nerve block and translaryngeal injection can be performed easily, safely and with a high success rate in patients with normal anatomy. In those with difficult landmarks, ultrasound can be of assistance. For the superior laryngeal nerve block, other targets than the nerve itself must be established to make the technique consistently successful, easy to teach, learn and perform. The same applies to the translaryngeal injection, where the use of ultrasound is necessary for correct midline identification. Intraoral glossopharyngeal nerve block is also safe and easy to perform, but associated with long lasting discomfort. Bilateral extraoral peristyloid approach should be discouraged since inadvertent blocks of the closely adjacent vagus nerve cannot be prevented in this location. A safe and easy method of blocking the distal portions of the glossopharyngeal nerve for awake intubation is therefore required. PMID:27276778

  19. MELANOPHORE BANDS AND AREAS DUE TO NERVE CUTTING, IN RELATION TO THE PROTRACTED ACTIVITY OF NERVES

    PubMed Central

    Parker, G. H.

    1941-01-01

    1. When appropriate chromatic nerves are cut caudal bands, cephalic areas, and the pelvic fins of the catfish Ameiurus darken. In pale fishes all these areas will sooner or later blanch. By recutting their nerves all such blanched areas will darken again. 2. These observations show that the darkening of caudal bands, areas, and fins on cutting their nerves is not due to paralysis (Brücke), to the obstruction of central influences such as inhibition (Zoond and Eyre), nor to vasomotor disturbances (Hogben), but to activities emanating from the cut itself. 3. The chief agents concerned with the color changes in Ameiurus are three: intermedin from the pituitary gland, acetylcholine from the dispersing nerves (cholinergic fibers), and adrenalin from the concentrating nerves (adrenergic fibers). The first two darken the fish; the third blanches it. In darkening the dispersing nerves appear to initiate the process and to be followed and substantially supplemented by intermedin. 4. Caudal bands blanch by lateral invasion, cephalic areas by lateral invasion and internal disintegration, and pelvic fins by a uniform process of general loss of tint equivalent to internal disintegration. 5. Adrenalin may be carried in such an oil as olive oil and may therefore act as a lipohumor; it is soluble in water and hence may act as a hydrohumor. In lateral invasion (caudal bands, cephalic areas) it probably acts as a lipohumor and in internal disintegration (cephalic areas, pelvic fins) it probably plays the part of a hydrohumor. 6. The duration of the activity of dispersing nerves after they had been cut was tested by means of the oscillograph, by anesthetizing blocks, and by cold-blocks. The nerves of Ameiurus proved to be unsatisfactory for oscillograph tests. An anesthetizing block, magnesium sulfate, is only partly satisfactory. A cold-block, 0°C., is successful to a limited degree. 7. By means of a cold-block it can be shown that dispersing autonomic nerve fibers in Ameiurus can

  20. Evaluation of neurolytic blocks using phenol and cryogenic block in the management of chronic pain.

    PubMed

    Ramamurthy, S; Walsh, N E; Schoenfeld, L S; Hoffman, J

    1989-06-01

    This study compared the use of phenol and cryogenic blocks for neurolysis in 28 patients. Patients were assigned randomly to receive peripheral nerve blocks with either phenol or cryoanalgesia. Significantly more patients in the phenol group received 20% or greater relief at 2, 12, and 24 wk than patients in the cryogenic group. Only 27% of patients received significant relief, however, indicating that neurolytic blocks were not particularly effective even though local anesthetic blocks produced significant but temporary pain relief. PMID:2732524

  1. Ultrasonographic evaluation of neck hematoma and block salvage after failed neurostimulation-guided interscalene block.

    PubMed

    Howell, Stephen M; Unger, M W Todd; Colson, James D; Serafini, Mario

    2010-11-01

    Ultrasound-guided regional anesthetic techniques have shown some advantages over conventional paresthesia and neurostimulation techniques. We report the case of a neurostimulation-guided continuous interscalene block that would have ended in complication were it not for experience with ultrasound-guided regional anesthesia. Familiarity with ultrasound-guided block techniques permitted assessment of a neck hematoma during interscalene block and ultimately allowed successful peripheral nerve block.

  2. Nerve Blockage Attenuates Postoperative Inflammation in Hippocampus of Young Rat Model with Surgical Trauma.

    PubMed

    He, Yi; Li, Zhi; Zuo, Yun-Xia

    2015-01-01

    It is hypothesized that central nervous system inflammation induced by systematic inflammation due to surgical trauma plays a critical role in postoperative cognitive dysfunction. The potential inhibitory effect of nerve blockage with local anesthetics on peripheral inflammatory response has been reported. We hypothesize that nerve blockage may be effective in reducing postoperative inflammation and cognitive decline. The rats at the age of 4 weeks were subjected to general anesthesia and humeral fracture fixation, in combination with brachial plexus block, saline versus ropivacaine, respectively. The rats from control group underwent general anesthesia only. The expression of proinflammatory cytokines in plasma and in hippocampus was measured. Open field test and new object recognition task were performed before surgery and on postoperative days (POD) 1, 3, and 7. Compared with control group, the level of cytokines in plasma and hippocampus revealed an obvious increase in surgery groups. The effect of brachial plexus block on decreasing cytokines was observed. The rats exposed to surgery without brachial plexus block showed behavior impairment. Our results indicated that nerve blockage could downregulate proinflammatory cytokines in hippocampus after humeral fixation surgery, which may ameliorate the postoperative cognitive dysfunction in young rats. PMID:26664150

  3. Raman microspectroscopy for visualization of peripheral nerves

    NASA Astrophysics Data System (ADS)

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

    2013-02-01

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

  4. Inhibition of nerve conduction by electromagnetic induction of the frog sciatic nerve-gastrocnemius muscle preparation.

    PubMed

    Wali, F A; Brain, A I

    1989-01-01

    The effect of electromagnetic induction (EMI) on impulse conduction and muscle contraction was studied in isolated sciatic nerve-gastrocnemius muscle preparation of the frog. Electrical stimulation (ES) of the sciatic nerve, at 0.5 Hz with 0.6 V (supramaximal) and 1-ms pulse duration, produced twitch contractions (3.5 +/- 0.4 g tension, mean +/- S.E., n = 8 frogs), which were reduced or blocked by EMI, applied to the nerve via an induction coil, from a d.c. source of 1.5-4 V, at a frequency of 100 min-1, for 2- to 4-min duration. Recovery of the blocked twitches was obtained within 4-5 min, after the cessation of the EMI and washing out the preparation in Ringer solution. The inhibition of the twitch tension by EMI was compared to that produced by an effective concentration of a local anaesthetic, lignocaine (1 microM), which is known to block conduction, by blocking ionic fluxes across the nerve membrane. It is possible that EMI also interferes with the ionic fluxes, and in prolonged duration, may produce changes in the myelin sheath (or the Schwann cells) of the nerve membrane. A comparison of ES with EMI was made, and it was concluded that EMI inhibited electrically induced neuromuscular transmission at the frog neuromuscular junction.

  5. Rehabilitation of the trigeminal nerve

    PubMed Central

    Iro, Heinrich; Bumm, Klaus; Waldfahrer, Frank

    2005-01-01

    When it comes to restoring impaired neural function by means of surgical reconstruction, sensory nerves have always been in the role of the neglected child when compared with motor nerves. Especially in the head and neck area, with its either sensory, motor or mixed cranial nerves, an impaired sensory function can cause severe medical conditions. When performing surgery in the head and neck area, sustaining neural function must not only be highest priority for motor but also for sensory nerves. In cases with obvious neural damage to sensory nerves, an immediate neural repair, if necessary with neural interposition grafts, is desirable. Also in cases with traumatic trigeminal damage, an immediate neural repair ought to be considered, especially since reconstructive measures at a later time mostly require for interposition grafts. In terms of the trigeminal neuralgia, commonly thought to arise from neurovascular brainstem compression, a pharmaceutical treatment is considered as the state of the art in terms of conservative therapy. A neurovascular decompression of the trigeminal root can be an alternative in some cases when surgical treatment is sought after. Besides the above mentioned therapeutic options, alternative treatments are available. PMID:22073060

  6. Ultrasound-guided truncal blocks: A new frontier in regional anaesthesia

    PubMed Central

    Chakraborty, Arunangshu; Khemka, Rakhi; Datta, Taniya

    2016-01-01

    The practice of regional anaesthesia is rapidly changing with the introduction of ultrasound into the working domain of the anaesthesiologist. New techniques are being pioneered. Among the recent techniques, notable are the truncal blocks, for example, the transversus abdominis plane block, rectus sheath block, hernia block and quadratus lumborum block in the abdomen and the pectoral nerves (Pecs) block 1 and 2, serratus anterior plane block and intercostal nerve block. This narrative review covers the brief anatomical discourse along with technical description of the ultrasound-guided truncal blocks. PMID:27761032

  7. Release of somatostatin and its role in the mediation of the anti-inflammatory effect induced by antidromic stimulation of sensory fibres of rat sciatic nerve

    PubMed Central

    Szolcsányi, János; Helyes, Zsuzsanna; Oroszi, Gábor; Németh, József; Pintér, Erika

    1998-01-01

    The effect of antidromic stimulation of the sensory fibres of the sciatic nerve on inflammatory plasma extravasation in various tissues and on cutaneous vasodilatation elicited in distant parts of the body was investigated in rats pretreated with guanethidine (8 mg kg−1, i.p.) and pipecuronium (200 μg kg−1, i.v.).Antidromic sciatic nerve stimulation with C-fibre strength (20 V, 0.5 ms) at 5 Hz for 5 min elicited neurogenic inflammation in the innervated area and inhibited by 50.3±4.67% the development of a subsequent plasma extravasation in response to similar stimulation of the contralateral sciatic nerve. Stimulation at 0.5 Hz for 1 h also evoked local plasma extravasation and inhibited the carrageenin-induced (1%, 100 μl s.c.) cutaneous inflammation by 38.5±10.0% in the contralateral paw. Excitation at 0.1 Hz for 4 h elicited no local plasma extravasation in the stimulated hindleg but still reduced the carrageenin-induced oedema by 52.1±9.7% in the paw on the contralateral side.Plasma extravasation in the knee joint in response to carrageenin (2%, 200 μl intra-articular injection) was diminished by 46.1±12.69% and 40.9±4.93% when the sciatic nerve was stimulated in the contralateral leg at 0.5 Hz for 1 h or 0.1 Hz for 4 h, respectively.Stimulation of the peripheral stump of the left vagal nerve (20 V, 1 ms, 8 Hz, 10 min) elicited plasma extravasation in the trachea, oesophagus and mediastinal connective tissue in rats pretreated with atropine (2 mg kg−1, i.v.), guanethidine (8 mg kg−1, i.p.) and pipecuronium (200 μg kg−1, i.v.). These responses were inhibited by 37.8±5.1%, 49.7±9.9% and 37.6±4.2%, respectively by antidromic sciatic nerve excitation (5 Hz, 5 min) applied 5 min earlier.Pretreatment with polyclonal somatostatin antiserum (0.5 ml/rat, i.v.) or the selective somatostatin depleting agent cysteamine (280 mg kg−1, s.c.) prevented the anti-inflammatory effect of

  8. The role of median nerve terminal latency index in the diagnosis of carpal tunnel syndrome in comparison with other electrodiagnostic parameters

    PubMed Central

    Vahdatpour, Babak; Khosrawi, Saeid; Chatraei, Maryam

    2016-01-01

    Background: Carpal tunnel syndrome (CTS) considers the most common compression neuropathy, which nerve conduction studies (NCSs) used for its detection routinely and universally. This study was performed to determine the value of the median TLI and other NCS variables and to investigate their sensitivity and specificity in the diagnosis of CTS. Materials and Methods: The study was carried out among 100 hands of healthy volunteers and 50 hands of patients who had a positive history of paresthesia and numbness in upper extremities. Information including age, gender, and result of sensory and motor nerve conduction velocity (MNCV), peak latency difference of median and ulnar nerves of fourth digit (M4-U4 peak latency difference), and TLI were recorded for analysis. Sensitivity and specificity of electro diagnostic parameters in the diagnosis of CTS was investigated. Results: Normal range of the median nerve TLI was 0.43 ± 0.077. There was no significant difference between two groups for MNCV means (P = 0. 45). Distal sensory latency and distal motor latency (DML) of median nerve and fourth digit median-ulnar peak latency differences (PM4-PU4) for CTS group was significantly higher (P < 0.001) and mean for sensory nerve conduction velocity was significantly higher in control group (P < 0.001). The most sensitive electrophysiological finding in CTS patients was median TLI (82%), but the most specific one was DML (98%). Conclusion: Although in early stages of CTS, we usually expect only abnormalities in the sensory studies, but TLI may better demonstrate the effect on median nerve motor fiber even in mild cases of CTS. PMID:27376049

  9. Population Blocks.

    ERIC Educational Resources Information Center

    Smith, Martin H.

    1992-01-01

    Describes an educational game called "Population Blocks" that is designed to illustrate the concept of exponential growth of the human population and some potential effects of overpopulation. The game material consists of wooden blocks; 18 blocks are painted green (representing land), 7 are painted blue (representing water); and the remaining…

  10. Common peroneal nerve dysfunction

    MedlinePlus

    ... toe-out movements Tests of nerve activity include: Electromyography (EMG, a test of electrical activity in muscles) Nerve ... Peroneal neuropathy. In: Preston DC, Shapiro BE, eds. Electromyography and Neuromuscular Disorders . 3rd ed. Philadelphia, PA: Elsevier; ...

  11. Nerve conduction velocity

    MedlinePlus

    ... to measure the speed of the nerve signals. Electromyography (recording from needles placed into the muscles) is ... Often, the nerve conduction test is followed by electromyography (EMG). In this test, needles are placed into ...

  12. Electromechanical Nerve Stimulator

    NASA Technical Reports Server (NTRS)

    Tcheng, Ping; Supplee, Frank H., Jr.; Prass, Richard L.

    1993-01-01

    Nerve stimulator applies and/or measures precisely controlled force and/or displacement to nerve so response of nerve measured. Consists of three major components connected in tandem: miniature probe with spherical tip; transducer; and actuator. Probe applies force to nerve, transducer measures force and sends feedback signal to control circuitry, and actuator positions force transducer and probe. Separate box houses control circuits and panel. Operator uses panel to select operating mode and parameters. Stimulator used in research to characterize behavior of nerve under various conditions of temperature, anesthesia, ventilation, and prior damage to nerve. Also used clinically to assess damage to nerve from disease or accident and to monitor response of nerve during surgery.

  13. Nerve Injuries in Athletes.

    ERIC Educational Resources Information Center

    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)

  14. The role of intracellular calcium in A-23187 stimulated and beta-adrenoceptor blocking drug treated blood platelets.

    PubMed

    Nosál, R; Jancinová, V; Petríková, M

    1994-06-15

    A significant concentration-dependent difference was found between beta-adrenoceptor blocking drugs in their ability to inhibit A23187-induced isolated platelet aggregation. In the absence of extracellular calcium ions the following rank order of potency to inhibit calcium ionophore stimulated platelet aggregation was shown: propranolol > bevantolol > alprenolol > metipranolol > oxprenolol > atenolol > pindolol > metoprolol approximately sotalol approximately practolol. The interruption of induced aggregation, as well as inhibition of aggregation, in the absence of extracellular calcium ions indicated interference of inhibitory beta-adrenoceptor blocking drugs with intramembrane or intraplatelet calcium pools activated with A23187. This suggestion was supported by the reversal of the inhibitory effect of beta-adrenoceptor blocking drugs in the presence of extracellular calcium ions. The effect was dose dependent and occurred within 30 sec after calcium administration. The results indicated that inhibitory beta-adrenoceptor blocking drugs, possessing a cationic amphiphilic structure, suppressed calcium mobilization in A23187-stimulated platelets, most probably after entering platelets. This explains why lipophilic drugs are more effective than hydrophilic ones in calcium ionophore A23187-stimulated platelets.

  15. [ROLE OF CAPSAICIN-SENSITIVE NERVES IN THE REGULATION OF DEHYDROEPIANDROSTERONE SULFATE BLOOD CONTENT UNDER NORMAL AND FRUCTOSE-INDUCED METABOLIC SYNDROME].

    PubMed

    Spiridonov, V K; Tolochko, Z S; Ovcjukova, M V; Kostina, N E; Obut, T A

    2015-08-01

    The effects of the stimulation of capsaicin-sensitive nerves (capsaicin, 1 mg/kg, s/c) and their eafferentation (capsaicin, 150 mg/kg, s/c) on the blood content of dehydroepiandrosterone sulfate (DHEAS) was investigated in normal rats and rats with fructose-induced metabolic syndrome (12.5% fructose solution, 10 weeks). An increase in blood of tryglyceride, lipid peroxidation, glucose (fasting and after loading glucose, 2 mg/kg, i/p) was considered as symptoms of metabolic syndrome. It was shown that in normal rats drinking tap water the stimulation of capsaicin-sensitive nerves resulted in the increase of DHEAS content while their deafferentation reduced the concentration of this hormone in the blood. The fructose diet caused the decrease in content of DHEAS, triglyceridemia, lipid peroxidation, impaired tolerance glucose. In rats with the metabolic syndrome the stimulation capsaicin-sensitive nerves prevented the fructose-induced decrease of DHEAS content as well as decreased the symptoms of metabolic syndrome. In fructose fed rats the stimulation-induced effects were prevented by the deafferentation of capsaicin-sensitive nerves. It is suggested that capsaicin-sensitive nerves contribute both to the regulation of blood content of DHEAS under normal and fructose-induced metabolic syndrome.

  16. Dynamics and sensitivity analysis of high-frequency conduction block

    NASA Astrophysics Data System (ADS)

    Ackermann, D. Michael; Bhadra, Niloy; Gerges, Meana; Thomas, Peter J.

    2011-10-01

    The local delivery of extracellular high-frequency stimulation (HFS) has been shown to be a fast acting and quickly reversible method of blocking neural conduction and is currently being pursued for several clinical indications. However, the mechanism for this type of nerve block remains unclear. In this study, we investigate two hypotheses: (1) depolarizing currents promote conduction block via inactivation of sodium channels and (2) the gating dynamics of the fast sodium channel are the primary determinate of minimal blocking frequency. Hypothesis 1 was investigated using a combined modeling and experimental study to investigate the effect of depolarizing and hyperpolarizing currents on high-frequency block. The results of the modeling study show that both depolarizing and hyperpolarizing currents play an important role in conduction block and that the conductance to each of three ionic currents increases relative to resting values during HFS. However, depolarizing currents were found to promote the blocking effect, and hyperpolarizing currents were found to diminish the blocking effect. Inward sodium currents were larger than the sum of the outward currents, resulting in a net depolarization of the nodal membrane. Our experimental results support these findings and closely match results from the equivalent modeling scenario: intra-peritoneal administration of the persistent sodium channel blocker ranolazine resulted in an increase in the amplitude of HFS required to produce conduction block in rats, confirming that depolarizing currents promote the conduction block phenomenon. Hypothesis 2 was investigated using a spectral analysis of the channel gating variables in a single-fiber axon model. The results of this study suggested a relationship between the dynamical properties of specific ion channel gating elements and the contributions of corresponding conductances to block onset. Specifically, we show that the dynamics of the fast sodium inactivation gate are

  17. Tension neuropathy of the superficial peroneal nerve: associated conditions and results of release.

    PubMed

    Johnston, E C; Howell, S J

    1999-09-01

    We reviewed eight patients who sustained superficial peroneal nerve neuralgia after an inversion ankle sprain. Surgical exploration found anatomic abnormalities that tethered the nerve from movement during plantarflexion and inversion of the ankle. Most patients' pain improved dramatically after release and anterior transposition of the nerve. Seven joints also underwent arthroscopy, which showed intra-articular disease that was consistent with the original trauma. Five patients had reflex sympathetic dystrophy, three of which resolved after nerve release. Nerve conduction studies were not helpful. Careful physical examination and local nerve blocks were most important in making the diagnosis and prescribing treatment. All conservative measures should be exhausted before surgery is considered.

  18. Distal nerve entrapment following nerve repair.

    PubMed

    Schoeller, T; Otto, A; Wechselberger, G; Pommer, B; Papp, C

    1998-04-01

    Failure of nerve repair or poor functional outcome after reconstruction can be influenced by various causes. Besides improper microsurgical technique, fascicular malalignment and unphysiologic tension, we found in our clinical series that a subclinical nerve compression distal to the repair site can seriously impair regeneration. We concluded that the injured nerve, whether from trauma or microsurgical intervention, could be more susceptible to distal entrapment in the regenerative stage because of its disturbed microcirculation, swelling and the increase of regenerating axons followed by increased nerve volume. In two cases we found the regenerating nerve entrapped at pre-existing anatomical sites of narrowing resulting in impaired functional recovery. In both cases the surgical therapy was decompression of the distal entrapped nerve and this was followed by continued regeneration. Thorough clinical and electrophysiologic follow-up is necessary to detect such adverse compression effects and to distinguish between the various causes of failed regeneration. Under certain circumstances primary preventive decompression may be beneficial if performed at the time of nerve coaptation.

  19. Role of Amphiphilic Block Copolymer Composition on Pore Characteristics of Micelle-Templated Mesoporous Cobalt Oxide Films.

    PubMed

    Wang, Siyang; Tangvijitsakul, Pattarasai; Qiang, Zhe; Bhaway, Sarang M; Lin, Kehua; Cavicchi, Kevin A; Soucek, Mark D; Vogt, Bryan D

    2016-04-26

    Block copolymer templating is a versatile approach for the generation of well-defined porosity in a wide variety of framework chemistries. Here, we systematically investigate how the composition of a poly(methoxy poly[ethylene glycol] methacrylate)-block-poly(butyl acrylate) (PMPEG-PBA) template impacts the pore characteristics of mesoporous cobalt oxide films. Three templates with a constant PMPEG segment length and different hydrophilic block volume fractions of 17%, 51%, and 68% for the PMPEG-PBA are cooperatively assembled with cobalt nitrate hexahydrate and citric acid. Irrespective of template composition, a spherical nanostructure is templated and elliptical mesostructures are obtained on calcination due to uniaxial contraction of the film. The average pore size increases from 11.4 ± 2.8 to 48.5 ± 4.3 nm as the length of the PBA segment increases as determined from AFM. For all three templates examined, a maximum in porosity (∼35% in all cases) and surface area is obtained when the precursor solids contain 35-45 wt % PMPEG-PBA. This invariance suggests that the total polymer content drives the structure through interfacial assembly. The composition for maximizing porosity and surface area with the micelle-templating approach results from a general decrease in porosity with increasing cobalt nitrate hexahydrate content and the increasing mechanical integrity of the framework to resist collapse during template removal/crystallization as the cobalt nitrate hexahydrate content increases. Unlike typical evaporation induced self-assembly with sol-gel chemistry, the hydrophilic/hydrophobic composition of the block copolymer template is not a critical component to the mesostructure developed with micelle-templating using metal nitrate-citric acid as the precursor. PMID:27040316

  20. [Hypoglossal nerve neuropraxia after shoulder hemiarthroplasty].

    PubMed

    Pariente, L; Camarena, P; Koo, M; Sabaté, A; Armengol, J

    2014-05-01

    We report a case of hypoglossal nerve damage after shoulder hemiarthroplasty with the patient in "beach chair" position, performed with general anesthesia with orotracheal intubation, and without complications. An ultrasound-guided interscalene block was previously performed in an alert patient. After the intervention, the patient showed clinical symptomatology compatible with paralysis of the right hypoglossal nerve that completely disappeared after 4 weeks. Mechanisms such as hyperextension of the neck during intubation, endotracheal tube cuff pressure, excessive hyperextension, or head lateralization during surgery have been described as causes of this neurological damage. We discuss the causes, the associated factors and suggest preventive measures.

  1. Autologous fibrin glue in peripheral nerve regeneration in vivo.

    PubMed

    Choi, Byung-Ho; Han, Sang-Gyun; Kim, Sung-Hoon; Zhu, Shi-Jiang; Huh, Jin-Young; Jung, Jae-Hyung; Lee, Seoung-Ho; Kim, Byung-Yong

    2005-01-01

    The activity of several growth factors on peripheral nerve regeneration is reported. Autologous fibrin glue contains a large number of platelets, which release significant quantities of growth factors. In order to understand the role of autologous fibrin glue in peripheral nerve regeneration, a 15-mm rabbit peroneal nerve defect was repaired using a vein graft filled with autologous fibrin glue. Axonal regeneration was examined using histological and electrophysiological methods. The extent of axonal regeneration was superior when treated with autologous fibrin glue. Our data suggest that fibrin nets formed by fibrinogen, in combination with growth factors present in autologous fibrin glue, might effectively promote peripheral nerve regeneration in nerve defects.

  2. Benign glandular inclusions in parotid nerve.

    PubMed

    Cramer, S F; Heggeness, L M

    1988-08-01

    Benign salivary ductular and acinar structures were demonstrated within an enlarged, disorderly intraparotid nerve in association with a mucoepidermoid carcinoma that did not, itself, manifest perineural invasion. Salivary gland can thus be added to the growing list of tissues in which "perineural invasion" by noncancerous epithelium has been observed. The proliferative features of the neural tissue in this case support the notion that neural elements may play an active role in the establishment of intimate neural-epithelial relationships. The mechanism for this phenomenon in the present case is postulated to be proliferation and ingrowth of the nerve tissue, possibly mediated by nerve growth factor or some related substance.

  3. Pleiotrophin and peripheral nerve injury.

    PubMed

    Jin, Li; Jianghai, Chen; Juan, Liu; Hao, Kang

    2009-10-01

    The proto-oncogene pleiotrophin, discovered in 1989, was considered as a multifunctional growth factor, which played an important role in tumor occurrence, development, and central nervous system. The latest research showed that pleiotrophin signal pathway probably participated in neural repair after peripheral nerve injury, especially in the following critical points, such as the protection of spinal cord neuron, the promotion of the speed of neuron axon regeneration, the guidance of neuron axon regeneration, skeleton muscle reinnervation, and so on. It potentially plays a key role in the guidance of neural axon regeneration in peripheral nervous system and muscle reinnervation. With the deepening of related researches, pleiotrophin gene would become a controllable target for improving the repairing effect of peripheral nerve injury and reconstruction of the neuromuscular junction.

  4. A role for apolipoprotein E, apolipoprotein A-I, and low density lipoprotein receptors in cholesterol transport during regeneration and remyelination of the rat sciatic nerve.

    PubMed Central

    Boyles, J K; Zoellner, C D; Anderson, L J; Kosik, L M; Pitas, R E; Weisgraber, K H; Hui, D Y; Mahley, R W; Gebicke-Haerter, P J; Ignatius, M J

    1989-01-01

    Recent work has demonstrated that apo E secretion and accumulation increase in the regenerating peripheral nerve. The fact that apoE, in conjunction with apoA-I and LDL receptors, participates in a well-established lipid transfer system raised the possibility that apoE is also involved in lipid transport in the injured nerve. In the present study of the crushed rat sciatic nerve, a combination of techniques was used to trace the cellular associations of apoE, apoA-I, and the LDL receptor during nerve repair and to determine the distribution of lipid at each stage. After a crush injury, as axons died and Schwann cells reabsorbed myelin, resident and monocyte-derived macrophages produced large quantities of apoE distal to the injury site. As axons regenerated in the first week, their tips contained a high concentration of LDL receptors. After axon regeneration, apoE and apoA-I began to accumulate distal to the injury site and macrophages became increasingly cholesterol-loaded. As remyelination began in the second and third weeks after injury, Schwann cells exhausted their cholesterol stores, then displayed increased LDL receptors. Depletion of macrophage cholesterol stores followed over the next several weeks. During this stage of regeneration, apoE and apoA-I were present in the extracellular matrix as components of cholesterol-rich lipoproteins. Our results demonstrate that the regenerating peripheral nerve possesses the components of a cholesterol transfer mechanism, and the sequence of events suggests that this mechanism supplies the cholesterol required for rapid membrane biogenesis during axon regeneration and remyelination. Images PMID:2493483

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

    SciTech Connect

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

    1988-09-01

    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 {sup 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.

  6. Extract of Hypericum perforatum blocks caffeine-induced locomotor activity in mice: a possible role of nitric oxide.

    PubMed

    Uzbay, I Tayfun; Coskun, Ilke; Kayir, Hakan; Ozturk, Nilgun; Ozturk, Yusuf

    2007-05-01

    The present study investigated the effects of HPE on caffeine-induced locomotor activity in mice. Caffeine (4-16 mg/kg) or saline were given to adult male Swiss-Webster mice, and the locomotor activity was immediately measured for 30 min. HPE (6-48 mg/kg) and saline were injected to another group of mice and the locomotor activity was measured 20 min later. HPE (6-24 mg/kg) was also administered to another group of mice 20 min before caffeine (16 mg/kg) injections and the locomotor activity was recorded for 30 min immediately after caffeine administrations. Finally l-arginine (1 g/kg) was administered i.p. 20 min before HPE (6 mg/kg) and the locomotor activity was measured as mentioned above. Each group of mice was used only once. Caffeine produced some significant increases in locomotor activity of the mice. HPE (6-24 mg/kg) significantly blocked the caffeine-induced locomotor hyperactivity. Pretreatment of l-arginine (1 g/kg) reversed the inhibitory effect of HPE (6 mg/kg) on caffeine-induced locomotor activity without producing any significant effect on locomotor activity of the mice when it was administered alone. The results suggest that HPE blocks caffeine-induced locomotor hyperactivity in mice. Furthermore, the inhibitory effect of HPE on caffeine-induced locomotor activity may be related to its NOS inhibitory property.

  7. The role of ultra-fast solvent evaporation on the directed self-assembly of block polymer thin films

    NASA Astrophysics Data System (ADS)

    Drapes, Chloe; Nelson, G.; Grant, M.; Wong, J.; Baruth, A.

    The directed self-assembly of nano-structures in block polymer thin films viasolvent vapor annealing is complicated by several factors, including evaporation rate. Solvent vapor annealing exposes a disordered film to solvent(s) in the vapor phase, increasing mobility and tuning surface energy, with the intention of producing an ordered structure. Recent theoretical predictions reveal the solvent evaporation affects the resultant nano-structuring. In a competition between phase separation and kinetic trapping during drying, faster solvent removal can enhance the propagation of a given morphology into the bulk of the thin film down to the substrate. Recent construction of a purpose-built, computer controlled solvent vapor annealing chamber provides control over forced solvent evaporation down to 15 ms. This is accomplished using pneumatically actuated nitrogen flow into and out of the chamber. Furthermore, in situ spectral reflectance, with 10 ms temporal resolution, monitors the swelling and evaporation. Presently, cylinder-forming polystyrene-block-polylactide thin films were swollen with 40% (by volume) tetrahydrofuran, followed by immediate evaporation under a variety of designed conditions. This includes various evaporation times, ranging from 15 ms to several seconds, and four unique rate trajectories, including linear, exponential, and combinations. Atomic force microscopy reveals specific surface, free and substrate, morphologies of the resultant films, dependent on specific evaporation conditions. Funded by the Clare Boothe Luce Foundation and Nebraska EPSCoR.

  8. [Dilated cardiomyopathy: the role of left branch of atrioventricular bundle block in left ventricular walls longitudinal strain indices change].

    PubMed

    Trembovetskaya, E M; Knyshov, G V; Zaharova, V P; Rudenko, K V

    2015-03-01

    Activity of the heart is assured by the myocardium motion with a composite path, which can be described with various quantitative indices, in particular the strain ones. The invention and implementation into clinical practice the "Speckle Tracking" ultrasonic technology, based on the two-dimensional echocardiography, allows to study of normal myocardium function as well as its functioning in various hart lesions, in particular, dilated cardiomyopathy (DCMP). Peculiarities of the features of longitudinal strain parameters of left ventricular (LV) walls in patients with DCMP, according to the occurrence of the total left branch of atrioventricular bundle block were studied. In DCMP the indices of longitudinal myocardial strain of the LV were strongly decreasing with the augmenting of heart failure signs. The appearance of the total left branch of atrioventricular bundle block, manifested by the total decrease of amplitude of longitudinal strain of the lateral and posterior walls of the LV, led to the augmenting of mitral regurgitation (up to 2+) and increase of the pulmonary hypertension, augmenting of circulatory deficiency signs.

  9. The evolution of health warning labels on cigarette packs: the role of precedents, and tobacco industry strategies to block diffusion

    PubMed Central

    Hiilamo, Heikki; Crosbie, Eric; Glantz, Stanton A

    2013-01-01

    Objective To analyse the evolution and diffusion of health warnings on cigarette packs around the world, including tobacco industry attempts to block this diffusion. Methods We analysed tobacco industry documents and public sources to construct a database on the global evolution and diffusion of health warning labels from 1966 to 2012, and also analysed industry strategies. Results Health warning labels, especially labels with graphic elements, threaten the tobacco industry because they are a low-cost, effective measure to reduce smoking. Multinational tobacco companies did not object to voluntary innocuous warnings with ambiguous health messages, in part because they saw them as offering protection from lawsuits and local packaging regulations. The companies worked systematically at the international level to block or weaken warnings once stronger more specific warnings began to appear in the 1970s. Since 1985 in Iceland, the tobacco industry has been aware of the effectiveness of graphic health warning labels (GWHL). The industry launched an all-out attack in the early 1990s to prevent GHWLs, and was successful in delaying GHWLs internationally for nearly 10 years. Conclusions Beginning in 2005, as a result of the World Health Organisation Framework Convention on Tobacco Control (FCTC), GHWLs began to spread. Effective implementation of FCTC labelling provisions has stimulated diffusion of strong health warning labels despite industry opposition. PMID:23092884

  10. The role of block rotations and oroclinal bending in Iran during the Cenozoic Arabia-Eurasia shortening

    NASA Astrophysics Data System (ADS)

    Cifelli, F.; Mattei, M.; Alimohammadian, H.; Sabouri, J.; Rashid, H.; Ghassemi, M.

    2012-04-01

    Shortening related to the Arabia-Eurasia convergence in the Cenozoic has been - and is at present being - taken up mainly by displacements in the Zagros, Alborz, and Kopeh Dag thrust-and-fold belts of Iran, whereas the intervening, fault-bounded crustal blocks of Central Iran (Yazd, Tabas and Lut blocks) show little internal deformation. Central Iran is separated from the Alborz belt by NE-SW left-lateral strike-slip and thrust faults (e.g., the Great Kavir fault), whereas N-S right-lateral strike-slip faults define the boundary between the Tabas and Lut blocks within Central Iran (e.g., the Neyband fault). Based on structural and seismological data, it has been proposed that NE-SW left-lateral and N-S right-lateral faults can accommodate the NNE-SSW Arabia-Eurasia convergence if they are allowed to rotate clockwise (CW) and counterclockwise (CCW), respectively. A rotating-fault deformation model predicts that the intervening fault-bounded rigid blocks should rotate accordingly. To test this hypothesis, paleomagnetic sampling was carried out on Oligocene-Miocene sediments from different areas of Central Iran (Torud, Jandaq, Anarak, Tabas, Yazd, Bafq, Ferdows), dominated by right-lateral and left-lateral strike slip faults activity, and along the southeastern margin of the Alborz Mts. (Bastam, Tall, Gardaneye-Ahovan, Momenabad Abdolabad), where left lateral and thrust faults prevail. Large counterclockwise (CCW) rotations (20°-35°) have been measured in the Tabas and Yazd blocks, characterized by the presence of N-S to NNW-SSE trending, right-lateral strike-slip faults. This structural domain is bounded to the north by the ENE-WSW oriented Great Kavir-Doruneh left-lateral strike-slip fault system. North of this fault paleomagnetic data show a different behaviour, with no or small CW rotation about vertical axis during the late Tertiary. In particular a small amount of CW rotation has been measured in the Jandaq and Torud area, to the north of the Great Kavir fault

  11. Ionic Blocks

    ERIC Educational Resources Information Center

    Sevcik, Richard S.; Gamble, Rex; Martinez, Elizabet; Schultz, Linda D.; Alexander, Susan V.

    2008-01-01

    "Ionic Blocks" is a teaching tool designed to help middle school students visualize the concepts of ions, ionic compounds, and stoichiometry. It can also assist high school students in reviewing their subject mastery. Three dimensional blocks are used to represent cations and anions, with color indicating charge (positive or negative) and size…

  12. The Furcal Nerve Revisited

    PubMed Central

    Dabke, Harshad V.

    2014-01-01

    Atypical sciatica and discrepancy between clinical presentation and imaging findings is a dilemma for treating surgeon in management of lumbar disc herniation. It also constitutes ground for failed back surgery and potential litigations thereof. Furcal nerve (Furcal = forked) is an independent nerve with its own ventral and dorsal branches (rootlets) and forms a link nerve that connects lumbar and sacral plexus. Its fibers branch out to be part of femoral and obturator nerves in-addition to the lumbosacral trunk. It is most commonly found at L4 level and is the most common cause of atypical presentation of radiculopathy/sciatica. Very little is published about the furcal nerve and many are unaware of its existence. This article summarizes all the existing evidence about furcal nerve in English literature in an attempt to create awareness and offer insight about this unique entity to fellow colleagues/professionals involved in spine care. PMID:25317309

  13. Neuregulin-1 signaling is essential for nerve-dependent axolotl limb regeneration.

    PubMed

    Farkas, Johanna E; Freitas, Polina D; Bryant, Donald M; Whited, Jessica L; Monaghan, James R

    2016-08-01

    The Mexican axolotl (Ambystoma mexicanum) is capable of fully regenerating amputated limbs, but denervation of the limb inhibits the formation of the post-injury proliferative mass called the blastema. The molecular basis behind this phenomenon remains poorly understood, but previous studies have suggested that nerves support regeneration via the secretion of essential growth-promoting factors. An essential nerve-derived factor must be found in the blastema, capable of rescuing regeneration in denervated limbs, and its inhibition must prevent regeneration. Here, we show that the neuronally secreted protein Neuregulin-1 (NRG1) fulfills all these criteria in the axolotl. Immunohistochemistry and in situ hybridization of NRG1 and its active receptor ErbB2 revealed that they are expressed in regenerating blastemas but lost upon denervation. NRG1 was localized to the wound epithelium prior to blastema formation and was later strongly expressed in proliferating blastemal cells. Supplementation by implantation of NRG1-soaked beads rescued regeneration to digits in denervated limbs, and pharmacological inhibition of NRG1 signaling reduced cell proliferation, blocked blastema formation and induced aberrant collagen deposition in fully innervated limbs. Taken together, our results show that nerve-dependent NRG1/ErbB2 signaling promotes blastemal proliferation in the regenerating limb and may play an essential role in blastema formation, thus providing insight into the longstanding question of why nerves are required for axolotl limb regeneration.

  14. Neuregulin-1 signaling is essential for nerve-dependent axolotl limb regeneration.

    PubMed

    Farkas, Johanna E; Freitas, Polina D; Bryant, Donald M; Whited, Jessica L; Monaghan, James R

    2016-08-01

    The Mexican axolotl (Ambystoma mexicanum) is capable of fully regenerating amputated limbs, but denervation of the limb inhibits the formation of the post-injury proliferative mass called the blastema. The molecular basis behind this phenomenon remains poorly understood, but previous studies have suggested that nerves support regeneration via the secretion of essential growth-promoting factors. An essential nerve-derived factor must be found in the blastema, capable of rescuing regeneration in denervated limbs, and its inhibition must prevent regeneration. Here, we show that the neuronally secreted protein Neuregulin-1 (NRG1) fulfills all these criteria in the axolotl. Immunohistochemistry and in situ hybridization of NRG1 and its active receptor ErbB2 revealed that they are expressed in regenerating blastemas but lost upon denervation. NRG1 was localized to the wound epithelium prior to blastema formation and was later strongly expressed in proliferating blastemal cells. Supplementation by implantation of NRG1-soaked beads rescued regeneration to digits in denervated limbs, and pharmacological inhibition of NRG1 signaling reduced cell proliferation, blocked blastema formation and induced aberrant collagen deposition in fully innervated limbs. Taken together, our results show that nerve-dependent NRG1/ErbB2 signaling promotes blastemal proliferation in the regenerating limb and may play an essential role in blastema formation, thus providing insight into the longstanding question of why nerves are required for axolotl limb regeneration. PMID:27317805

  15. Nerve injuries due to obstetric trauma.

    PubMed

    Bhat, V; Ravikumara; Oumachigui, A

    1995-01-01

    The incidence of nerve injuries among 32,637 deliveries over a period of ten years was 1.81/1000. Brachial plexus injury (1/1000) and facial nerve injury (0.74/1000) accounted for 98% of nerve injuries. Both the right and left side were involved equally. Bilateral nerve injury was not seen. Lack of antenatal care, macrosomia, abnormal presentations, and operative vaginal deliveries significantly increased the risk of nerve injuries. These babies had significantly higher incidence of meconium stained liquor and intrapartum asphyxia. Parity of the mother, gestational age and sex of the baby did not have significant role in the causation of nerve injuries. Injuries to brachial plexus and facial nerve were seen even in babies born by caesarean section, when it was performed for obstructed labour caused by cephalo-pelvic disproportion and abnormal presentations. Three babies with injuries expired and forty-three could be followed up for varying periods. None of the babies had residual defects. Detection of cephalopelvic disproportion and abnormal lie in the third trimester and their appropriate management would decrease the incidence of obstetric palsies to a significant extent. PMID:10829869

  16. Decoy receptors block TRAIL sensitivity at a supracellular level: the role of stromal cells in controlling tumour TRAIL sensitivity.

    PubMed

    O'Leary, L; van der Sloot, A M; Reis, C R; Deegan, S; Ryan, A E; Dhami, S P S; Murillo, L S; Cool, R H; Correa de Sampaio, P; Thompson, K; Murphy, G; Quax, W J; Serrano, L; Samali, A; Szegezdi, E

    2016-03-10

    Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is a death ligand cytokine known for its cytotoxic activity against malignantly transformed cells. TRAIL induces cell death through binding to death receptors DR4 and DR5. The inhibitory decoy receptors (DcR1 and DcR2) co-expressed with death receptor 4 (DR4)/DR5 on the same cell can block the transmission of the apoptotic signal. Here, we show that DcRs also regulate TRAIL sensitivity at a supracellular level and thus represent a mechanism by which the microenvironment can diminish tumour TRAIL sensitivity. Mathematical modelling and layered or spheroid stroma-extracellular matrix-tumour cultures were used to model the tumour microenvironment. By engineering TRAIL to escape binding by DcRs, we found that DcRs do not only act in a cell-autonomous or cis-regulatory manner, but also exert trans-cellular regulation originating from stromal cells and affect tumour cells, highlighting the potent inhibitory effect of DcRs in the tumour tissue and the necessity of selective targeting of the two death-inducing TRAIL receptors to maximise efficacy. PMID:26050621

  17. Pudendal Neuralgia Due to Pudendal Nerve Entrapment: Warning Signs Observed in Two Cases and Review of the Literature.

    PubMed

    Ploteau, Stephanie; Cardaillac, Claire; Perrouin-Verbe, Marie-Aimee; Riant, Thibault; Labat, Jean-Jacques

    2016-03-01

    Pudendal neuralgia is a chronic neuropathic pelvic pain that is often misdiagnosed and inappropriately treated. The Nantes criteria provide a basis for the diagnosis of pudendal neuralgia due to pudendal nerve entrapment. The 5 essential diagnostic criteria are pain situated in the anatomical territory of the pudendal nerve, worsened by sitting, the patient is not woken at night by the pain, and no objective sensory loss is detected on clinical examination. The fifth criterion is a positive pudendal nerve block. We have also clarified a number of complementary diagnostic criteria and several exclusion criteria that make the diagnosis unlikely. When pudendal neuralgia due to pudendal nerve entrapment is diagnosed according to the Nantes criteria, no further investigation is required and medical or surgical treatment can be proposed. Nevertheless, a number of warning signs suggesting other possible causes of pudendal neuralgia must not be overlooked. These warning signs (red flags) are waking up at night, excessively neuropathic nature of the pain (for example, associated with hypoesthesia), specifically pinpointed pain, which can suggest neuroma and pain associated with neurological deficit. In these atypical presentations, the diagnosis of pain due to pudendal nerve entrapment should be reconsidered and a radiological examination should be performed. The 2 cases described in this report (tumor compression of the pudendal nerve) illustrate the need to recognize atypical pudendal neuralgia and clarify the role of pelvic magnetic resonance imaging (MRI), as MRI provides very valuable information for the evaluation of diseases involving the ischiorectal fossa. The presence of red flags must be investigated in all cases of pudendal neuralgia to avoid missing pudendal neuralgia secondary to a mechanism other than nerve entrapment.

  18. Primary brain targets of nerve agents

    PubMed Central

    Aroniadou-Anderjaska, Vassiliki; Figueiredo, Taiza H.; Apland, James P.; Qashu, Felicia; Braga, Maria F.M.

    2009-01-01

    Exposure to nerve agents and other organophosphorus acetylcholinesterases used in industry and agriculture can cause death, or brain damage, producing long-term cognitive and behavioral deficits. Brain damage is primarily caused by the intense seizure activity induced by these agents. Identifying the brain regions that respond most intensely to nerve agents, in terms of generating and spreading seizure activity, along with knowledge of the physiology and biochemistry of these regions, can facilitate the development of pharmacological treatments that will effectively control seizures even if administered when seizures are well underway. Here, we contrast the pathological (neuronal damage) and pathophysiological (neuronal activity) findings of responses to nerve agents in the amygdala and the hippocampus, the two brain structures that play a central role in the generation and spread of seizures. The evidence so far suggests that the amygdala suffers the most extensive damage by nerve agent exposure, which appears consistent with the tendency of the amygdala to generate prolonged, seizure-like neuronal discharges in vitro in response to the nerve agent soman, at a time when the hippocampus generates only interictal-like activity. In vivo experiments are now required to confirm the primary role that the amygdala seems to play in nerve agent-induced seizure generation. PMID:19591865

  19. Low intensity laser treatment of nerve injuries

    NASA Astrophysics Data System (ADS)

    Liu, Xiao-Guang; Liu, Timon Cheng-Yi; Luo, Qing-Ming

    2007-05-01

    The neural regeneration and functional recovery after nerve injuries has long been an important field in neuroscience. Low intensity laser (LIL) irradiation is a novel and useful tool for the treatment of many injuries and disorders. The aim of this study was to assess the role of LIL irradiation in the treatment of peripheral and central nerve injuries. Some animal experiments and clinical investigations have shown beneficial effects of LIL irradiation on neural tissues, but its therapeutic value and efficacy are controversial. Reviewing the data of experimental and clinical studies by using the biological information model of photobiomodulation, we conclude that LIL irradiation in specific parameters can promote the regeneration of injured peripheral and central nerves and LIL therapy is a safe and valuable treatment for superficial peripheral nerve injuries and spinal cord injury. The biological effects of LIL treatment depend largely on laser wavelength, power and dose per site and effective irradiation doses are location-specific.

  20. Inferior alveolar nerve repositioning.

    PubMed

    Louis, P J

    2001-09-01

    Nerve repositioning is a viable alternative for patients with an atrophic edentulous posterior mandible. Patients, however, should be informed of the potential risks of neurosensory disturbance. Documentation of the patient's baseline neurosensory function should be performed with a two-point discrimination test or directional brush stroke test preoperatively and postoperatively. Recovery of nerve function should be expected in 3 to 6 months. The potential for mandibular fracture when combining nerve repositioning with implant placement also should be discussed with the patient. This can be avoided by minimizing the amount of buccal cortical plate removal during localization of the nerve and maintaining the integrity of the inferior cortex of the mandible. Additionally, avoid overseating the implant, thus avoiding stress along the inferior border of the mandible. The procedure does allow for the placement of longer implants, which should improve implant longevity. Patients undergoing this procedure have expressed overall satisfaction with the results. Nerve repositioning also can be used to preserve the inferior alveolar nerve during resection of benign tumors or cysts of the mandible. This procedure allows the surgeon to maintain nerve function in situations in which the nerve would otherwise have to be resected. PMID:11665379

  1. Cryotherapy and nerve palsy.

    PubMed

    Drez, D; Faust, D C; Evans, J P

    1981-01-01

    Ice application is one of the most extensively used treatments for athletic injuries. Frostbite is a recognized danger. Five cases of nerve palsy resulting from ice application are reported here. These palsies were temporary. They usually resolve spontaneously without any significant sequelae. This complication can be avoided by not using ice for more than 30 minutes and by guarding superficial nerves in the area.

  2. Imaging the cranial nerves.

    PubMed

    Parry, Andrew T; Volk, Holger A

    2011-01-01

    An understanding of the normal course of the cranial nerves (CN) is essential when interpreting images of patients with cranial neuropathies. CN foramina are depicted best using computed X-ray tomography, but the nerves are depicted best using magnetic resonance imaging. The function and anatomy of the CN in the dog are reviewed and selected examples of lesions affecting the CN are illustrated.

  3. [Sciatic nerve intraneural perineurioma].

    PubMed

    Bonhomme, Benjamin; Poussange, Nicolas; Le Collen, Philippe; Fabre, Thierry; Vital, Anne; Lepreux, Sébastien

    2015-12-01

    Intraneural perineurioma is a benign tumor developed from the perineurium and responsible for localized nerve hypertrophy. This uncommon tumor is characterized by a proliferation of perineural cells with a "pseudo-onion bulb" pattern. We report a sciatic nerve intraneural perineurioma in a 39-year-old patient. PMID:26586011

  4. Optic Nerve Decompression

    MedlinePlus

    ... canals). The optic nerve is the “nerve of vision” and extends from the brain, through your skull, and into your eye. A ... limited to, the following: loss of vision, double vision, inadequate ... leakage of brain fluid (CSF), meningitis, nasal bleeding, infection of the ...

  5. Accessory Upper Subscapular Nerve – The Neurotisation Tool

    PubMed Central

    Deshmukh, Vishwajit Ravindra; Mandal, Rabindra Prasad; Kusuma, Harisha

    2016-01-01

    During the routine dissection classes for undergraduate students, uncommon variation in relation to the upper subscapular nerve of posterior cord of brachial plexus was observed. Normally upper subscapular nerve takes origin from the posterior cord, but in this case report, it arises in triplet fashion, just above the circumflex scapular artery. All these accessory nerves were supplying upper part of the subscapularis muscle. As per our knowledge, this is a rare variation of brachial plexus. Many variations are encountered in the formation of brachial plexus. The normal and the abnormal origin of nerves are important considering neurotisation surgeries as well as during the infraclavicular nerve block for various axillary and upper limb surgeries. PMID:27790416

  6. Ulnar nerve tuberculoma.

    PubMed

    Ramesh Chandra, V V; Prasad, Bodapati Chandramowliswara; Varaprasad, Gangumolu

    2013-01-01

    The authors report a very rare case of tuberculoma involving the ulnar nerve. The patient, a 7-year-old girl, presented with swelling over the medial aspect of her right forearm just below the elbow joint, with features of ulnar nerve palsy, including paresthesias along the little and ring fingers and claw hand deformity. There was a history of trauma and contact with a contagious case of tuberculosis. There were no other signs of tuberculosis. At surgical exploration the ulnar nerve was found to be thickened, and on opening the sheath there was evidence of caseous material enclosed in a fibrous capsule compressing and displacing the nerve fibers. The lesion, along with the capsule, was subtotally removed using curettage, and a part of the capsule that was densely adherent to the nerve fibers was left in the patient. Histopathological examination of the specimen was consistent with tuberculoma. The patient received adequate antitubercular treatment and showed significant improvement.

  7. Peripheral nerve stimulation: definition.

    PubMed

    Abejón, David; Pérez-Cajaraville, Juan

    2011-01-01

    Recently, there has been a tremendous evolution in the field of neurostimulation, both from the technological point of view and from development of the new and different indications. In some areas, such as peripheral nerve stimulation, there has been a boom in recent years due to the variations in the surgical technique and the improved results documented by in multiple published papers. All this makes imperative the need to classify and define the different types of stimulation that are used today. The confusion arises when attempting to describe peripheral nerve stimulation and subcutaneous stimulation. Peripheral nerve stimulation, in its pure definition, involves implanting a lead on a nerve, with the aim to produce paresthesia along the entire trajectory of the stimulated nerve.

  8. Social cognition: empirical contribution. The developmental building blocks of psychopathic traits: revisiting the role of theory of mind.

    PubMed

    Sharp, Carla; Vanwoerden, Salome

    2014-02-01

    In the context of personality disorder development, theories of typical and atypical development both emphasize social cognition as an important building block for personality development. Prior claims of intact theory of mind (ToM) abilities in psychopathic individuals have relied upon a narrow conception of ToM as equivalent to "cognitive empathy." In this article, the authors make use of a broader conception of ToM comprising top-down and bottom-up processing, as well as the fractionation of ToM in terms of reduced or excessive ToM function, to examine relationships between ToM and psychopathic traits. A total of 342 adolescents (ages 12-17; Mage 15.39; SD = 1.45; 61.5% females) completed the Movie Assessment for Social Cognition (Dziobek, Fleck, Kalbe, et al., 2006) and the Child Eyes Test (Baron-Cohen, Wheelwright, Hill, Raste, & Plumb, 2001) in addition to three measures of psychopathic traits. Results demonstrated unique relations between the affective components of psychopathy (callous-unemotional traits [CU traits]) and impairment in both top-down and bottom-up ToM. In addition, excessive ToM related to affective components of psychopathy, while reduced or no ToM related to behavioral components of psychopathy. In mediational analyses, bottom-up ToM was shown to be necessary for top-town ToM in its relation with CU traits. Taken together, these results from the study lend support to revisiting the link between ToM and psychopathy. PMID:24344889

  9. Social cognition: empirical contribution. The developmental building blocks of psychopathic traits: revisiting the role of theory of mind.

    PubMed

    Sharp, Carla; Vanwoerden, Salome

    2014-02-01

    In the context of personality disorder development, theories of typical and atypical development both emphasize social cognition as an important building block for personality development. Prior claims of intact theory of mind (ToM) abilities in psychopathic individuals have relied upon a narrow conception of ToM as equivalent to "cognitive empathy." In this article, the authors make use of a broader conception of ToM comprising top-down and bottom-up processing, as well as the fractionation of ToM in terms of reduced or excessive ToM function, to examine relationships between ToM and psychopathic traits. A total of 342 adolescents (ages 12-17; Mage 15.39; SD = 1.45; 61.5% females) completed the Movie Assessment for Social Cognition (Dziobek, Fleck, Kalbe, et al., 2006) and the Child Eyes Test (Baron-Cohen, Wheelwright, Hill, Raste, & Plumb, 2001) in addition to three measures of psychopathic traits. Results demonstrated unique relations between the affective components of psychopathy (callous-unemotional traits [CU traits]) and impairment in both top-down and bottom-up ToM. In addition, excessive ToM related to affective components of psychopathy, while reduced or no ToM related to behavioral components of psychopathy. In mediational analyses, bottom-up ToM was shown to be necessary for top-town ToM in its relation with CU traits. Taken together, these results from the study lend support to revisiting the link between ToM and psychopathy.

  10. Anomalous Facial Nerve: An Unusual Cause of Obstruction of Middle Ear Ventilation.

    PubMed

    Das, S; Tuli, I P

    2015-01-01

    Numerous anomalies and variations of facial nerve anatomy leading to iatrogenic injury are described. However, there are no reports of facial nerve dehiscence near its second genu causing a hump and obstructing middle ear ventilation pathway, as found in our case. This particular anomaly of facial nerve is being reported to highlight its uniqueness and that a dehiscent facial nerve may be a rare but dangerous cause of obstruction of the attic ventilation. One has to be aware of this unusual anomaly to prevent inadvertent damage to the facial nerve while clearing aditus block in persistent otitis media. PMID:26620754

  11. Interventional multispectral photoacoustic imaging with a clinical ultrasound probe for discriminating nerves and tendons: an ex vivo pilot study.

    PubMed

    Mari, Jean Martial; Xia, Wenfeng; West, Simeon J; Desjardins, Adrien E

    2015-11-01

    Accurate and efficient identification of nerves is an essential component of peripheral nerve blocks. While ultrasound (US) imaging is increasingly used as a guidance modality, it often provides insufficient contrast for identifying nerves from surrounding tissues such as tendons. Electrical nerve stimulators can be used in conjunction with US imaging for discriminating nerves from surrounding tissues, but they are insufficient to reliably prevent neural punctures, so that alternative methods are highly desirable. In this study, an interventional multispectral photoacoustic (PA) imaging system was used to directly compare the signal amplitudes and spectra acquired from nerves and tendons ex vivo, for the first time. The results indicate that the system can provide significantly higher image contrast for discriminating nerves and tendons than that provided by US imaging. As such, photoacoustic imaging could be valuable as an adjunct to US for guiding peripheral nerve blocks. PMID:26580699

  12. Interventional multispectral photoacoustic imaging with a clinical ultrasound probe for discriminating nerves and tendons: an ex vivo pilot study

    NASA Astrophysics Data System (ADS)

    Mari, Jean Martial; Xia, Wenfeng; West, Simeon J.; Desjardins, Adrien E.

    2015-11-01

    Accurate and efficient identification of nerves is an essential component of peripheral nerve blocks. While ultrasound (US) imaging is increasingly used as a guidance modality, it often provides insufficient contrast for identifying nerves from surrounding tissues such as tendons. Electrical nerve stimulators can be used in conjunction with US imaging for discriminating nerves from surrounding tissues, but they are insufficient to reliably prevent neural punctures, so that alternative methods are highly desirable. In this study, an interventional multispectral photoacoustic (PA) imaging system was used to directly compare the signal amplitudes and spectra acquired from nerves and tendons ex vivo, for the first time. The results indicate that the system can provide significantly higher image contrast for discriminating nerves and tendons than that provided by US imaging. As such, photoacoustic imaging could be valuable as an adjunct to US for guiding peripheral nerve blocks.

  13. Interventional multispectral photoacoustic imaging with a clinical ultrasound probe for discriminating nerves and tendons: an ex vivo pilot study.

    PubMed

    Mari, Jean Martial; Xia, Wenfeng; West, Simeon J; Desjardins, Adrien E

    2015-11-01

    Accurate and efficient identification of nerves is an essential component of peripheral nerve blocks. While ultrasound (US) imaging is increasingly used as a guidance modality, it often provides insufficient contrast for identifying nerves from surrounding tissues such as tendons. Electrical nerve stimulators can be used in conjunction with US imaging for discriminating nerves from surrounding tissues, but they are insufficient to reliably prevent neural punctures, so that alternative methods are highly desirable. In this study, an interventional multispectral photoacoustic (PA) imaging system was used to directly compare the signal amplitudes and spectra acquired from nerves and tendons ex vivo, for the first time. The results indicate that the system can provide significantly higher image contrast for discriminating nerves and tendons than that provided by US imaging. As such, photoacoustic imaging could be valuable as an adjunct to US for guiding peripheral nerve blocks.

  14. Sympathetic nerve-derived ATP regulates renal medullary vasa recta diameter via pericyte cells: a role for regulating medullary blood flow?

    PubMed

    Crawford, C; Wildman, S S P; Kelly, M C; Kennedy-Lydon, T M; Peppiatt-Wildman, C M

    2013-01-01

    Pericyte cells are now known to be a novel locus of blood flow control, being able to regulate capillary diameter via their unique morphology and expression of contractile proteins. We have previously shown that exogenous ATP causes constriction of vasa recta via renal pericytes, acting at a variety of membrane bound P2 receptors on descending vasa recta (DVR), and therefore may be able to regulate medullary blood flow (MBF). Regulation of MBF is essential for appropriate urine concentration and providing essential oxygen and nutrients to this region of high, and variable, metabolic demand. Various sources of endogenous ATP have been proposed, including from epithelial, endothelial, and red blood cells in response to stimuli such as mechanical stimulation, local acidosis, hypoxia, and exposure to various hormones. Extensive sympathetic innervation of the nephron has previously been shown, however the innervation reported has focused around the proximal and distal tubules, and ascending loop of Henle. We hypothesize that sympathetic nerves are an additional source of ATP acting at renal pericytes and therefore regulate MBF. Using a rat live kidney slice model in combination with video imaging and confocal microscopy techniques we firstly show sympathetic nerves in close proximity to vasa recta pericytes in both the outer and inner medulla. Secondly, we demonstrate pharmacological stimulation of sympathetic nerves in situ (by tyramine) evokes pericyte-mediated vasoconstriction of vasa recta capillaries; inhibited by the application of the P2 receptor antagonist suramin. Lastly, tyramine-evoked vasoconstriction of vasa recta by pericytes is significantly less than ATP-evoked vasoconstriction. Sympathetic innervation may provide an additional level of functional regulation in the renal medulla that is highly localized. It now needs to be determined under which physiological/pathophysiological circumstances that sympathetic innervation of renal pericytes is important

  15. Resolving writer's block.

    PubMed Central

    Huston, P.

    1998-01-01

    PROBLEM BEING ADDRESSED: Writer's block, or a distinctly uncomfortable inability to write, can interfere with professional productivity. OBJECTIVE OF PROGRAM: To identify writer's block and to outline suggestions for its early diagnosis, treatment, and prevention. MAIN COMPONENTS OF PROGRAM: Once the diagnosis has been established, a stepwise approach to care is recommended. Mild blockage can be resolved by evaluating and revising expectations, conducting a task analysis, and giving oneself positive feedback. Moderate blockage can be addressed by creative exercises, such as brainstorming and role-playing. Recalcitrant blockage can be resolved with therapy. Writer's block can be prevented by taking opportunities to write at the beginning of projects, working with a supportive group of people, and cultivating an ongoing interest in writing. CONCLUSIONS: Writer's block is a highly treatable condition. A systematic approach can help to alleviate anxiety, build confidence, and give people the information they need to work productively. PMID:9481467

  16. Focused ultrasound effects on nerve action potential in vitro

    PubMed Central

    Colucci, Vincent; Strichartz, Gary; Jolesz, Ferenc; Vykhodtseva, Natalia; Hynynen, Kullervo

    2009-01-01

    Minimally invasive applications of thermal and mechanical energy to selective areas of the human anatomy have led to significant advances in treatment of and recovery from typical surgical interventions. Image-guided focused ultrasound allows energy to be deposited deep into the tissue, completely noninvasively. There has long been interest in using this focal energy delivery to block nerve conduction for pain control and local anesthesia. In this study, we have performed an in vitro study to further extend our knowledge of this potential clinical application. The sciatic nerves from the bullfrog (Rana catesbeiana) were subjected to focused ultrasound (at frequencies of 0.661MHz and 1.986MHz) and to heated Ringer’s solution. The nerve action potential was shown to decrease in the experiments and correlated with temperature elevation measured in the nerve. The action potential recovered either completely, partially, or not at all, depending on the parameters of the ultrasound exposure. The reduction of the baseline nerve temperature by circulating cooling fluid through the sonication chamber did not prevent the collapse of the nerve action potential; but higher power was required to induce the same endpoint as without cooling. These results indicate that a thermal mechanism of focused ultrasound can be used to block nerve conduction, either temporarily or permanently. PMID:19647923

  17. Hypothalamic Paraventricular and Arcuate Nuclei Contribute to Elevated Sympathetic Nerve Activity in Pregnant Rats: Roles of Neuropeptide Y and α-Melanocyte-Stimulating Hormone.

    PubMed

    Shi, Zhigang; Cassaglia, Priscila A; Gotthardt, Laura C; Brooks, Virginia L

    2015-12-01

    Pregnancy increases sympathetic nerve activity (SNA), but the mechanisms are unknown. Here, we investigated the contributions of the hypothalamic paraventricular and arcuate nuclei in α-chloralose-anesthetized pregnant and nonpregnant rats. Baseline arterial pressure (AP) was lower, and heart rate (HR), lumbar sympathetic activity, and splanchnic SNA were higher in pregnant rats compared with nonpregnant rats. Inhibition of the paraventricular nucleus via bilateral muscimol nanoinjections decreased AP and HR more in pregnant rats than in nonpregnant rats and decreased lumbar SNA only in pregnant rats. Similarly, after arcuate muscimol nanoninjections, the decreases in AP, HR, and lumbar, renal, and splanchnic sympathetic nerve activities were greater in pregnant rats than in nonpregnant rats. Major arcuate neuronal groups that project to the paraventricular nucleus express inhibitory neuropeptide Y (NPY) and excitatory α-melanocyte-stimulating hormone. Inhibition of paraventricular melanocortin 3/4 receptors with SHU9119 also decreased AP, HR, and lumbar SNA in pregnant rats but not in nonpregnant rats. Conversely, paraventricular nucleus NPY expression was reduced in pregnant animals, and although blockade of paraventricular NPY Y1 receptors increased AP, HR, and lumbar sympathetic activity in nonpregnant rats, it had no effects in pregnant rats. Yet, the sympathoinhibitory, depressor, and bradycardic effects of paraventricular NPY nanoinjections were similar between groups. In conclusion, the paraventricular and arcuate nuclei contribute to increased basal SNA during pregnancy, likely due in part to decreased tonic NPY inhibition and increased tonic α-melanocyte-stimulating hormone excitation of presympathetic neurons in the paraventricular nucleus.

  18. Roles for the sympathetic nervous system, renal nerves, and CNS melanocortin-4 receptor in the elevated blood pressure in hyperandrogenemic female rats

    PubMed Central

    Maranon, Rodrigo; Lima, Roberta; Spradley, Frank T.; do Carmo, Jussara M.; Zhang, Howei; Smith, Andrew D.; Bui, Elizabeth; Thomas, R. Lucas; Moulana, Mohadetheh; Hall, John E.; Granger, Joey P.

    2015-01-01

    Women with polycystic ovary syndrome (PCOS) have hyperandrogenemia and increased prevalence of risk factors for cardiovascular disease, including elevated blood pressure. We recently characterized a hyperandrogenemic female rat (HAF) model of PCOS [chronic dihydrotestosterone (DHT) beginning at 4 wk of age] that exhibits similar characteristics as women with PCOS. In the present studies we tested the hypotheses that the elevated blood pressure in HAF rats is mediated in part by sympathetic activation, renal nerves, and melanocortin-4 receptor (MC4R) activation. Adrenergic blockade with terazosin and propranolol or renal denervation reduced mean arterial pressure (MAP by telemetry) in HAF rats but not controls. Hypothalamic MC4R expression was higher in HAF rats than controls, and central nervous system MC4R antagonism with SHU-9119 (1 nmol/h icv) reduced MAP in HAF rats. Taking a genetic approach, MC4R null and wild-type (WT) female rats were treated with DHT or placebo from 5 to 16 wk of age. MC4R null rats were obese and had higher MAP than WT control rats, and while DHT increased MAP in WT controls, DHT failed to further increase MAP in MC4R null rats. These data suggest that increases in MAP with chronic hyperandrogenemia in female rats are due, in part, to activation of the sympathetic nervous system, renal nerves, and MC4R and may provide novel insights into the mechanisms responsible for hypertension in women with hyperandrogenemia such as PCOS. PMID:25695289

  19. Hypothalamic Paraventricular and Arcuate Nuclei Contribute to Elevated Sympathetic Nerve Activity in Pregnant Rats: Roles of Neuropeptide Y and α-Melanocyte-Stimulating Hormone.

    PubMed

    Shi, Zhigang; Cassaglia, Priscila A; Gotthardt, Laura C; Brooks, Virginia L

    2015-12-01

    Pregnancy increases sympathetic nerve activity (SNA), but the mechanisms are unknown. Here, we investigated the contributions of the hypothalamic paraventricular and arcuate nuclei in α-chloralose-anesthetized pregnant and nonpregnant rats. Baseline arterial pressure (AP) was lower, and heart rate (HR), lumbar sympathetic activity, and splanchnic SNA were higher in pregnant rats compared with nonpregnant rats. Inhibition of the paraventricular nucleus via bilateral muscimol nanoinjections decreased AP and HR more in pregnant rats than in nonpregnant rats and decreased lumbar SNA only in pregnant rats. Similarly, after arcuate muscimol nanoninjections, the decreases in AP, HR, and lumbar, renal, and splanchnic sympathetic nerve activities were greater in pregnant rats than in nonpregnant rats. Major arcuate neuronal groups that project to the paraventricular nucleus express inhibitory neuropeptide Y (NPY) and excitatory α-melanocyte-stimulating hormone. Inhibition of paraventricular melanocortin 3/4 receptors with SHU9119 also decreased AP, HR, and lumbar SNA in pregnant rats but not in nonpregnant rats. Conversely, paraventricular nucleus NPY expression was reduced in pregnant animals, and although blockade of paraventricular NPY Y1 receptors increased AP, HR, and lumbar sympathetic activity in nonpregnant rats, it had no effects in pregnant rats. Yet, the sympathoinhibitory, depressor, and bradycardic effects of paraventricular NPY nanoinjections were similar between groups. In conclusion, the paraventricular and arcuate nuclei contribute to increased basal SNA during pregnancy, likely due in part to decreased tonic NPY inhibition and increased tonic α-melanocyte-stimulating hormone excitation of presympathetic neurons in the paraventricular nucleus. PMID:26483343

  20. Intraparotid facial nerve neurofibroma.

    PubMed

    Sullivan, M J; Babyak, J W; Kartush, J M

    1987-02-01

    Neurogenic neoplasms of the intraparotid facial nerve are uncommon and are usually diagnosed intraoperatively by tissue biopsy. Fifty-six cases of primary neurogenic neoplasms involving the facial nerve have been reported. The majority of these have been schwannomas. A case of a solitary neurofibroma involving the main trunk of the facial nerve is presented. Schwannomas and neurofibromas have distinct histological features which must be considered prior to the management of these tumors. The management of neurogenic tumors associated with normal facial function is a particularly difficult problem. A new approach for the diagnosis and management of neurogenic neoplasms is described utilizing electroneurography. PMID:3807626

  1. Radial Nerve Tendon Transfers.

    PubMed

    Cheah, Andre Eu-Jin; Etcheson, Jennifer; Yao, Jeffrey

    2016-08-01

    Radial nerve palsy typically occurs as a result of trauma or iatrogenic injury and leads to the loss of wrist extension, finger extension, thumb extension, and a reduction in grip strength. In the absence of nerve recovery, reconstruction of motor function involves tendon transfer surgery. The most common donor tendons include the pronator teres, wrist flexors, and finger flexors. The type of tendon transfer is classified based on the donor for the extensor digitorum communis. Good outcomes have been reported for most methods of radial nerve tendon transfers as is typical for positional tendon transfers not requiring significant power. PMID:27387076

  2. Health care-seeking among Latino immigrants: blocked access, use of traditional medicine, and the role of religion.

    PubMed

    Ransford, H Edward; Carrillo, Frank R; Rivera, Yessenia

    2010-08-01

    Barriers to health care and use of cultural alternatives are studied from open-ended interviews of 96 Latino immigrants, 12 hometown association leaders, and five pastors and health outreach workers. Frequently mentioned barriers to approaching hospitals and clinics included problems in communication, establishing financial eligibility, and extremely long waits for service. We found frequent use of cultural alternatives, such as herbal medications, obtaining care from Mexican doctors, and some use of traditional healers. The role of religiosity is studied: prayer is viewed as fundamental to health, but the church is not perceived as an aid in physical health-seeking. Health care for Latino immigrants often involves a blend of mainstream and traditional medicine; the study discusses examples of respondents who navigate between the two systems within the interplay of culture and structure.

  3. Planning Block Play Experiences for Young Children.

    ERIC Educational Resources Information Center

    Baker, Betty Ruth

    Playing with blocks can facilitate the creative, social, emotional, physical, and cognitive development of young children. This article presents information and activities concerning block play and its role in young children's experience. Topics covered include: (1) types of blocks; (2) selection of blocks and accessories; (3) planning of the…

  4. Block People.

    ERIC Educational Resources Information Center

    Peterson, Rayma

    1999-01-01

    Discusses an activity in which students in an after-school art class drew one another on pieces of 2-by-4 scrap lumber in order to create a class portrait in three dimensions. Stresses that the portraits on the wood blocks were done in-the-round, or each side was covered. (CMK)

  5. High Ulnar Nerve Injuries: Nerve Transfers to Restore Function.

    PubMed

    Patterson, Jennifer Megan M

    2016-05-01

    Peripheral nerve injuries are challenging problems. Nerve transfers are one of many options available to surgeons caring for these patients, although they do not replace tendon transfers, nerve graft, or primary repair in all patients. Distal nerve transfers for the treatment of high ulnar nerve injuries allow for a shorter reinnervation period and improved ulnar intrinsic recovery, which are critical to function of the hand. PMID:27094893

  6. Automated optic-nerve-head analysis using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Kulkarni, Manish D.; Harman, Jonathan W.; Kim, Robert; Kirschbaum, Alan R.; Pedersen, Per; Everett, Matthew J.; Wei, Jay

    2002-06-01

    The early identification of glaucomatous development is extremely important for treatment of glaucoma. Analysis of optic-nerve-head features may play a crucial role for early glaucoma diagnostics. Here we propose a critical parameter, viz., nerve tissue area, which may prove to be extremely useful for detection of glaucoma in early stages. We report a novel and robust algorithm for OCT-based automatic, objective extraction of critical optic-nerve-head features such as optic disc, nerve tissue area, and optic cup for the first time.

  7. Facial Nerve Neuroma Management

    PubMed Central

    Weber, Peter C.; Osguthorpe, J. David

    1998-01-01

    Three facial nerve neuromas were identified in the academic year 1994-1995. Each case illustrates different management dilemmas. One patient with a grade III facial nerve palsy had a small geniculate ganglion neuroma with the dilemma of decompression versus resection clear nerve section margins. The second patient underwent facial neuroma resection with cable graft reconstruction, but the permanent sections were positive. The last patient had a massive neuroma in which grafting versus other facial reconstructive options were considered. These three cases illustrate some of the major controversies in facial nerve neuroma management. We discuss our decision-making plan and report our results. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5 PMID:17171043

  8. Diabetes and nerve damage

    MedlinePlus

    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 ...

  9. Sacral nerve stimulation.

    PubMed

    Matzel, K E; Stadelmaier, U; Besendörfer, M

    2004-01-01

    The current concept of recruiting residual function of an inadequate pelvic organ by electrostimulation involves stimulation of the sacral spinal nerves at the level of the sacral canal. The rationale for applying SNS to fecal incontinence was based on clinical observations of its effect on bowel habits and anorectal continence function in urologic patients (increased anorectal angulation and anal canal closure pressure) and on anatomic considerations: dissection demonstrated a dual peripheral nerve supply of the striated pelvic floor muscles that govern these functions. Because the sacral spinal nerve site is the most distal common location of this dual nerve supply, stimulating here can elicit both functions. Since the first application of SNS in fecal incontinence in 1994, this technique has been improved, the patient selection process modified, and the spectrum of indications expanded. At present SNS has been applied in more than 1300 patients with fecal incontinence limited.

  10. Degenerative Nerve Diseases

    MedlinePlus

    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 ...

  11. Damaged axillary nerve (image)

    MedlinePlus

    Conditions associated with axillary nerve dysfunction include fracture of the humerus (upper arm bone), pressure from casts or splints, and improper use of crutches. Other causes include systemic disorders that cause neuritis (inflammation of ...

  12. Iatrogenic accessory nerve injury.

    PubMed Central

    London, J.; London, N. J.; Kay, S. P.

    1996-01-01

    Accessory nerve injury produces considerable disability. The nerve is most frequently damaged as a complication of radical neck dissection, cervical lymph node biopsy and other surgical procedures. The problem is frequently compounded by a failure to recognise the error immediately after surgery when surgical repair has the greatest chance of success. We present cases which outline the risk of accessory nerve injury, the spectrum of clinical presentations and the problems produced by a failure to recognise the deficit. Regional anatomy, consequences of nerve damage and management options are discussed. Diagnostic biopsy of neck nodes should not be undertaken as a primary investigation and, when indicated, surgery in this region should be performed by suitably trained staff under well-defined conditions. Awareness of iatrogenic injury and its consequences would avoid delays in diagnosis and treatment. Images Figure 2 PMID:8678450

  13. Femoral nerve dysfunction

    MedlinePlus

    Neuropathy - femoral nerve; Femoral neuropathy ... Craig EJ, Clinchot DM. Femoral neuropathy. In: Frontera WR, Silver JK, Rizzo TD Jr, eds. Essentials of Physical Medicine and Rehabilitation: Musculoskeletal Disorders, Pain, and Rehabilitation . 3rd ...

  14. Diabetic Nerve Problems

    MedlinePlus

    ... the wrong times. This damage is called diabetic neuropathy. Over half of people with diabetes get it. ... change positions quickly Your doctor will diagnose diabetic neuropathy with a physical exam and nerve tests. Controlling ...

  15. Lower cranial nerves.

    PubMed

    Soldatos, Theodoros; Batra, Kiran; Blitz, Ari M; Chhabra, Avneesh

    2014-02-01

    Imaging evaluation of cranial neuropathies requires thorough knowledge of the anatomic, physiologic, and pathologic features of the cranial nerves, as well as detailed clinical information, which is necessary for tailoring the examinations, locating the abnormalities, and interpreting the imaging findings. This article provides clinical, anatomic, and radiological information on lower (7th to 12th) cranial nerves, along with high-resolution magnetic resonance images as a guide for optimal imaging technique, so as to improve the diagnosis of cranial neuropathy.

  16. Characterization of the effects of cannabinoids on guinea-pig tracheal smooth muscle tone: role in the modulation of acetylcholine release from parasympathetic nerves.

    PubMed

    Spicuzza, L; Haddad, E B; Birrell, M; Ling, A; Clarke, D; Venkatesan, P; Barnes, P J; Belvisi, M G

    2000-08-01

    We investigated the ability of the cannabinoid agonists CP55,940 (CB(1)/CB(2)) and anandamide (endogenous cannabinoid) to modulate electrical field stimulation (EFS)-induced acetylcholine (ACh) release from parasympathetic nerve terminals innervating guinea-pig trachea. We assessed whether modulation of transmitter release translated to an impact on functional responses by investigating the effect of these agents on contractile responses evoked by EFS and ACh. Furthermore, we evaluated the ability of these compounds to elicit bronchodilation in pre-contracted guinea-pig tracheal strips. CP55,940 and anandamide significantly inhibited EFS-evoked ACh release (maximal inhibition of 35.1+/-2.9% and 33.4+/-6.4% at 1 microM, P<0.05, respectively). The CB(1) receptor antagonist SR 141716A (1 microM), had no effect on ACh release and failed to reverse the inhibitory effect of CP55,940 (1 microM). Paradoxically, CP55,940 had no significant effect on EFS-evoked cholinergic contractile responses. Furthermore, CP55,940 did not relax pre-contracted tracheal strips or affect contractile responses to exogenous ACh. This lack of activity on smooth muscle tone is consistent with the fact that no detectable specific binding of [(3)H] CP55,940 was found in tracheal homogenates. These data suggest that cannabinoid agonists inhibit ACh release from cholinergic nerve terminals via activation of CB(2) receptors but that this inhibitory action does not impact on functional responses such as cholinergic contraction.

  17. Aberrant Dual Origin of the Dorsal Scapular Nerve and Its Communication with Long Thoracic Nerve: An Unusual Variation of the Brachial Plexus.

    PubMed

    Shilal, Poonam; Sarda, Rohit Kumar; Chhetri, Kalpana; Lama, Polly; Tamang, Binod Kumar

    2015-06-01

    Pre and post-fixed variations at roots of the brachial plexus have been well documented, however little is known about the variations that exist in the branches which arise from the brachial plexus. In this paper, we describe about one such rare variation related to the dorsal scapular and the long thoracic nerve, which are the branches arising from the roots of the brachial plexus. The variation was found during routine dissection. The dorsal scapular nerve, which routinely arises from the fifth cervical nerve root (C5), was seen to receive contributions from C5 as well as sixth cervical nerve (C6), while the long thoracic nerve arose from C6 and seventh cervical nerves (C7) only. Furthermore along with variations in origin of the dorsal scapular and long thoracic nerves, the brachial plexus was seen to exist as a prefixed plexus receiving a contribution from C4 nerve root. An aberrant communicating branch between the dorsal scapular and long thoracic nerve was also identified. Knowledge about the course and anatomy of such variations can be vital for understanding the aetiology of various conditions such as winging of scapula, interscapular pain, administration of cervical nerve blocks, surgeries and for effective management of regions and muscles supplied by dorsal scapular and long thoracic nerve.

  18. Dorsal clitoral nerve injury following transobturator midurethral sling

    PubMed Central

    Moss, Chailee F; Damitz, Lynn A; Gracely, Richard H; Mintz, Alice C; Zolnoun, Denniz A; Dellon, A Lee

    2016-01-01

    Introduction Transobturator slings can be successfully used to treat stress urinary incontinence and improve quality of life through a minimally invasive vaginal approach. Persistent postoperative pain can occur and pose diagnostic and therapeutic dilemmas. Following a sling procedure, a patient complained of pinching clitoral and perineal pain. Her symptoms of localized clitoral pinching and pain became generalized over the ensuing years, eventually encompassing the entire left vulvovaginal region. Aim The aim of this study was to highlight the clinical utility of conventional pain management techniques used for the evaluation and management of patients with postoperative pain following pelvic surgery. Methods We described a prototypical patient with persistent pain in and around the clitoral region complicating the clinical course of an otherwise successful sling procedure. We specifically discussed the utility of bedside sensory assessment techniques and selective nerve blocks in the evaluation and management of this prototypical patient. Results Neurosensory assessments and a selective nerve block enabled us to trace the source of the patient’s pain to nerve entrapment along the dorsal nerve of the clitoris. We then utilized a nerve stimulator-guided hydrodissection technique to release the scar contracture Conclusion This case demonstrates that the dorsal nerve of the clitoris is vulnerable to injury directly and/or indirectly. Assimilation of a time-honored pain management construct for the evaluation and management of patients’ pain may improve outcomes while obviating the need for invasive surgery. PMID:27729812

  19. High-resolution measurement of electrically-evoked vagus nerve activity in the anesthetized dog

    NASA Astrophysics Data System (ADS)

    Yoo, Paul B.; Lubock, Nathan B.; Hincapie, Juan G.; Ruble, Stephen B.; Hamann, Jason J.; Grill, Warren M.

    2013-04-01

    Objective. Not fully understanding the type of axons activated during vagus nerve stimulation (VNS) is one of several factors that limit the clinical efficacy of VNS therapies. The main goal of this study was to characterize the electrical recruitment of both myelinated and unmyelinated fibers within the cervical vagus nerve. Approach. In anesthetized dogs, recording nerve cuff electrodes were implanted on the vagus nerve following surgical excision of the epineurium. Both the vagal electroneurogram (ENG) and laryngeal muscle activity were recorded in response to stimulation of the right vagus nerve. Main results. Desheathing the nerve significantly increased the signal-to-noise ratio of the ENG by 1.2 to 9.9 dB, depending on the nerve fiber type. Repeated VNS following nerve transection or neuromuscular block (1) enabled the characterization of A-fibers, two sub-types of B-fibers, and unmyelinated C-fibers, (2) confirmed the absence of stimulation-evoked reflex compound nerve action potentials in both the ipsilateral and contralateral vagus nerves, and (3) provided evidence of stimulus spillover into muscle tissue surrounding the stimulating electrode. Significance. Given the anatomical similarities between the canine and human vagus nerves, the results of this study provide a template for better understanding the nerve fiber recruitment patterns associated with VNS therapies.

  20. Normalization of sonographical multifocal nerve enlargements in a MADSAM patient following a good clinical response to intravenous immunoglobulin.

    PubMed

    Tanaka, Kanta; Ota, Natsuko; Harada, Yuzuru; Wada, Ikko; Suenaga, Toshihiko

    2016-09-01

    Focal nerve enlargements at sites of conduction blocks can be visualized sonographically in patients with multifocal acquired demyelinating sensory and motor neuropathy (MADSAM). However, little is known about association between nerve morphological changes and treatment responses. Here we present a 73-year-old female MADSAM patient whose sonographical multifocal nerve enlargements normalized following a good treatment response. She was admitted to our department with progressive asymmetrical muscle weakness and sensory disturbances for 6 months. Ultrasonography revealed multifocal nerve enlargements at sites of electrophysiological demyelination. Intravenous immunoglobulin improved her symptoms and electrophysiological abnormalities. Six months later, ultrasonography revealed normalization of multifocal nerve enlargements. Contrary to our observations, one previous report described a MADSAM patient with persistent nerve enlargements at the sites of resolved conduction blocks. In this earlier patient, however, the time from onset to remission was approximately 30 months. Morphological changes of nerve enlargements in MADSAM may vary with treatment response. PMID:27460345

  1. Communications Between the Facial Nerve and the Vestibulocochlear Nerve, the Glossopharyngeal Nerve, and the Cervical Plexus.

    PubMed

    Hwang, Kun; Song, Ju Sung; Yang, Su Cheol

    2015-10-01

    The aim of this review is to elucidate the communications between the facial nerves or facial nerve and neighboring nerves: the vestibulocochlear nerve, the glossopharyngeal nerve, and the cervical plexus.In a PubMed search, 832 articles were searched using the terms "facial nerve and communication." Sixty-two abstracts were read and 16 full-text articles were reviewed. Among them, 8 articles were analyzed.The frequency of communication between the facial nerve and the vestibulocochlear nerve was the highest (82.3%) and the frequency of communication between the facial nerve and the glossopharyngeal nerve was the lowest (20%). The frequency of communication between the facial nerve and the cervical plexus was 65.2 ± 43.5%. The frequency of communication between the cervical branch and the marginal mandibular branch of the facial nerve was 24.7 ± 1.7%.Surgeons should be aware of the nerve communications, which are important during clinical examinations and surgical procedures of the facial nerves such as those communications involved in facial reconstructive surgery, neck dissection, and various nerve transfer procedures.

  2. Collagen synthesis in axotomized peripheral nerve: evidence against Schwann cell involvement.

    PubMed

    Eather, T F; Pollock, M

    1987-04-01

    To explore the role of Schwann cells in nerve collagen formation, fascicular collagen was measured in axotomized rat sciatic nerve after regeneration or permanent axotomy. The same increase in fascicular collagen was seen in both paradigms. Thus there is no evidence that Schwann cells unassociated with axons make an important contribution to nerve collagen synthesis after transection.

  3. Role of intraseptal anesthesia for pain-free dental treatment

    PubMed Central

    Gazal, G; Fareed, WM; Zafar, MS

    2016-01-01

    Pain control during the dental procedure is essentials and challenging. A complete efficacious pulp anesthesia has not been attained yet. The regional anesthesia such as inferior alveolar nerve block (IANB) only does not guarantee the effective anesthesia with patients suffering from irreversible pulpitis. This main aim of this review was to discuss various aspects of intraseptal dental anesthesia and its role significance in pain-free treatment in the dental office. In addition, reasons of failure and limitations of this technique have been highlighted. Literature search was conducted for peer-reviewed articles published in English language in last 30 years. Search words such as dental anesthesia, pain control, intraseptal, and nerve block were entered using a web of knowledge and Google scholar databases. Various dental local anesthesia techniques were reviewed. A combination of block anesthesia, buccal infiltration and intraligamentary injection resulted in deep anesthesia (P = 0.003), and higher success rate compared to IANB. For pain-free management of conditions such as irreversible pulpitis, buccal infiltration (4% articaine), and intraosseous injection (2% lidocaine) are better than intraligamentary and IANB injections. Similarly, nerve block is not always effective for pain-free root canal treatment hence, needing supplemental anesthesia. Intraseptal anesthesia is an efficient and effective technique that can be used in maxillary and mandibular adult dentition. This technique is also beneficial when used in conjunction to the regional block or local dental anesthesia. PMID:26955316

  4. Role of intraseptal anesthesia for pain-free dental treatment.

    PubMed

    Gazal, G; Fareed, W M; Zafar, M S

    2016-01-01

    Pain control during the dental procedure is essentials and challenging. A complete efficacious pulp anesthesia has not been attained yet. The regional anesthesia such as inferior alveolar nerve block (IANB) only does not guarantee the effective anesthesia with patients suffering from irreversible pulpitis. This main aim of this review was to discuss various aspects of intraseptal dental anesthesia and its role significance in pain-free treatment in the dental office. In addition, reasons of failure and limitations of this technique have been highlighted. Literature search was conducted for peer-reviewed articles published in English language in last 30 years. Search words such as dental anesthesia, pain control, intraseptal, and nerve block were entered using a web of knowledge and Google scholar databases. Various dental local anesthesia techniques were reviewed. A combination of block anesthesia, buccal infiltration and intraligamentary injection resulted in deep anesthesia (P = 0.003), and higher success rate compared to IANB. For pain-free management of conditions such as irreversible pulpitis, buccal infiltration (4% articaine), and intraosseous injection (2% lidocaine) are better than intraligamentary and IANB injections. Similarly, nerve block is not always effective for pain-free root canal treatment hence, needing supplemental anesthesia. Intraseptal anesthesia is an efficient and effective technique that can be used in maxillary and mandibular adult dentition. This technique is also beneficial when used in conjunction to the regional block or local dental anesthesia. PMID:26955316

  5. Acellular Nerve Allografts in Peripheral Nerve Regeneration: A Comparative Study

    PubMed Central

    Moore, Amy M.; MacEwan, Matthew; Santosa, Katherine B.; Chenard, Kristofer E.; Ray, Wilson Z.; Hunter, Daniel A.; Mackinnon, Susan E.; Johnson, Philip J.

    2011-01-01

    Background Processed nerve allografts offer a promising alternative to nerve autografts in the surgical management of peripheral nerve injuries where short deficits exist. Methods Three established models of acellular nerve allograft (cold-preserved, detergent-processed, and AxoGen® -processed nerve allografts) were compared to nerve isografts and silicone nerve guidance conduits in a 14 mm rat sciatic nerve defect. Results All acellular nerve grafts were superior to silicone nerve conduits in support of nerve regeneration. Detergent-processed allografts were similar to isografts at 6 weeks post-operatively, while AxoGen®-processed and cold-preserved allografts supported significantly fewer regenerating nerve fibers. Measurement of muscle force confirmed that detergent-processed allografts promoted isograft-equivalent levels of motor recovery 16 weeks post-operatively. All acellular allografts promoted greater amounts of motor recovery compared to silicone conduits. Conclusions These findings provide evidence that differential processing for removal of cellular constituents in preparing acellular nerve allografts affects recovery in vivo. PMID:21660979

  6. Role of percutaneous posterior tibial nerve stimulation either alone or combined with an anticholinergic agent in treating patients with overactive bladder

    PubMed Central

    Kızılyel, Sadık; Karakeçi, Ahmet; Ozan, Tunç; Ünüş, İhsan; Barut, Osman; Onur, Rahmi

    2015-01-01

    Objective To evaluate the efficacy of percutaneous tibial nerve stimulation (PTNS), either alone or combined with an anticholinergic agent, in treating patients with an overactive bladder (OAB) in whom previous conservative treatment failed. Material and methods In this study, we included a total of 30 female patients with OAB in whom all conventional therapies failed between January 2010 and April 2011. Patients were randomly divided into three groups: Group 1, PTNS group; Group 2, patients receiving an anticholinergic agent; and Group 3, patients receiving both PTNS and anticholinergic agent. PTNS treatment continued for 12 weeks with each session lasting 30 min. Results All parameters of the bladder diary significantly improved in all groups (p<0.05). Similarly, all scores measured by questionnaires (UDI-6, IIQ-7, and OABSS) revealed significant improvements in all groups. When the improvements in symptoms were compared among the groups, there was a statistically significantly higher improvement in groups 1 and 3 than in Group 2. Conclusion PTNS is a safe, simple, and minimally invasive treatment modality in patients with OAB, and it may be suggested either alone or in combination with anticholinergics when conventional treatments fail. PMID:26623150

  7. Neuromuscular ultrasound of cranial nerves.

    PubMed

    Tawfik, Eman A; Walker, Francis O; Cartwright, Michael S

    2015-04-01

    Ultrasound of cranial nerves is a novel subdomain of neuromuscular ultrasound (NMUS) which may provide additional value in the assessment of cranial nerves in different neuromuscular disorders. Whilst NMUS of peripheral nerves has been studied, NMUS of cranial nerves is considered in its initial stage of research, thus, there is a need to summarize the research results achieved to date. Detailed scanning protocols, which assist in mastery of the techniques, are briefly mentioned in the few reference textbooks available in the field. This review article focuses on ultrasound scanning techniques of the 4 accessible cranial nerves: optic, facial, vagus and spinal accessory nerves. The relevant literatures and potential future applications are discussed.

  8. Nerve Transfers in Birth Related Brachial Plexus Injuries: Where Do We Stand?

    PubMed

    Davidge, Kristen M; Clarke, Howard M; Borschel, Gregory H

    2016-05-01

    This article reviews the assessment and management of obstetrical brachial plexus palsy. The potential role of distal nerve transfers in the treatment of infants with Erb's palsy is discussed. Current evidence for motor outcomes after traditional reconstruction via interpositional nerve grafting and extraplexal nerve transfers is reviewed and compared with the recent literature on intraplexal distal nerve transfers in obstetrical brachial plexus injury. PMID:27094890

  9. Apoplastic barriers effectively block oxygen permeability across outer cell layers of rice roots under deoxygenated conditions: roles of apoplastic pores and of respiration.

    PubMed

    Kotula, Lukasz; Ranathunge, Kosala; Steudle, Ernst

    2009-12-01

    *Despite the importance of the barrier to oxygen losses of the roots of hygrophytes growing in wet environments devoid of oxygen, there are few data available on permeability coefficients for O(2) across outer root cell layers (P(OPR)) and how they may change in response to low O(2). *A gas perfusion technique was used to measure the P(OPR) of rice (Oryza sativa) plants grown in either aerated or deoxygenated solution. The contributions of the apoplast and of living cells to the overall P(OPR) were characterized either by blocking apoplastic pores with precipitates of brown Cu(2)[Fe(CN)(6)] or by killing cells with 0.1 N HCl. *Compared with that of plants from aerated hydroponics, the P(OPR) of plants grown in deoxygenated medium was smaller by an order of magnitude. Precipitates resulting from CuSO(4)/K(4)[Fe(CN)(6)] treatment only formed in plants grown in aerated solution, where they reduced the P(OPR) by 5-20%. Killing of root segments with HCl increased P(OPR) in plants grown in both conditions by 20-55%. *The results indicated that apoplastic barriers effectively restricted radial O(2) loss. The relative role of the respiratory O(2) consumption of root peripheral layers increased as P(OPR) decreased.

  10. 2D IR spectroscopy reveals the role of water in the binding of channel-blocking drugs to the influenza M2 channel

    SciTech Connect

    Ghosh, Ayanjeet E-mail: gai@sas.upenn.edu; Gai, Feng E-mail: gai@sas.upenn.edu; Hochstrasser, Robin M.; Wang, Jun; DeGrado, William F.; Moroz, Yurii S.; Korendovych, Ivan V.; Zanni, Martin

    2014-06-21

    Water is an integral part of the homotetrameric M2 proton channel of the influenza A virus, which not only assists proton conduction but could also play an important role in stabilizing channel-blocking drugs. Herein, we employ two dimensional infrared (2D IR) spectroscopy and site-specific IR probes, i.e., the amide I bands arising from isotopically labeled Ala30 and Gly34 residues, to probe how binding of either rimantadine or 7,7-spiran amine affects the water dynamics inside the M2 channel. Our results show, at neutral pH where the channel is non-conducting, that drug binding leads to a significant increase in the mobility of the channel water. A similar trend is also observed at pH 5.0 although the difference becomes smaller. Taken together, these results indicate that the channel water facilitates drug binding by increasing its entropy. Furthermore, the 2D IR spectral signatures obtained for both probes under different conditions collectively support a binding mechanism whereby amantadine-like drugs dock in the channel with their ammonium moiety pointing toward the histidine residues and interacting with a nearby water cluster, as predicted by molecular dynamics simulations. We believe these findings have important implications for designing new anti-influenza drugs.

  11. 2D IR spectroscopy reveals the role of water in the binding of channel-blocking drugs to the influenza M2 channel

    PubMed Central

    Ghosh, Ayanjeet; Wang, Jun; Moroz, Yurii S.; Korendovych, Ivan V.; Zanni, Martin; DeGrado, William F.; Gai, Feng; Hochstrasser, Robin M.

    2014-01-01

    Water is an integral part of the homotetrameric M2 proton channel of the influenza A virus, which not only assists proton conduction but could also play an important role in stabilizing channel-blocking drugs. Herein, we employ two dimensional infrared (2D IR) spectroscopy and site-specific IR probes, i.e., the amide I bands arising from isotopically labeled Ala30 and Gly34 residues, to probe how binding of either rimantadine or 7,7-spiran amine affects the water dynamics inside the M2 channel. Our results show, at neutral pH where the channel is non-conducting, that drug binding leads to a significant increase in the mobility of the channel water. A similar trend is also observed at pH 5.0 although the difference becomes smaller. Taken together, these results indicate that the channel water facilitates drug binding by increasing its entropy. Furthermore, the 2D IR spectral signatures obtained for both probes under different conditions collectively support a binding mechanism whereby amantadine-like drugs dock in the channel with their ammonium moiety pointing toward the histidine residues and interacting with a nearby water cluster, as predicted by molecular dynamics simulations. We believe these findings have important implications for designing new anti-influenza drugs. PMID:24952572

  12. Peripheral nerve regeneration and neurotrophic factors

    PubMed Central

    TERENGHI, GIORGIO

    1999-01-01

    The role of neurotrophic factors in the maintenance and survival of peripheral neuronal cells has been the subject of numerous studies. Administration of exogenous neurotrophic factors after nerve injury has been shown to mimic the effect of target organ-derived trophic factors on neuronal cells. After axotomy and during peripheral nerve regeneration, the neurotrophins NGF, NT-3 and BDNF show a well defined and selective beneficial effect on the survival and phenotypic expression of primary sensory neurons in dorsal root ganglia and of motoneurons in spinal cord. Other neurotrophic factors such as CNTF, GDNF and LIF also exert a variety of actions on neuronal cells, which appear to overlap and complement those of the neurotrophins. In addition, there is an indirect contribution of GGF to nerve regeneration. GGF is produced by neurons and stimulates proliferation of Schwann cells, underlining the close interaction between neuronal and glial cells during peripheral nerve regeneration. Different possibilities have been investigated for the delivery of growth factors to the injured neurons, in search of a suitable system for clinical applications. The studies reviewed in this article show the therapeutic potential of neurotrophic factors for the treatment of peripheral nerve injury and for neuropathies. PMID:10227662

  13. A role for complexes of survival of motor neurons (SMN) protein with gemins and profilin in neurite-like cytoplasmic extensions of cultured nerve cells

    SciTech Connect

    Sharma, Aarti; Lambrechts, Anja; Le thi Hao; Le, Thanh T.; Sewry, Caroline A.; Ampe, Christophe; Burghes, Arthur H.M.; Morris, Glenn E. . E-mail: glenn.morris@rjah.nhs.uk

    2005-09-10

    Spinal muscular atrophy (SMA) is caused by reduced levels of SMN (survival of motor neurons protein) and consequent loss of motor neurons. SMN is involved in snRNP transport and nuclear RNA splicing, but axonal transport of SMN has also been shown to occur in motor neurons. SMN also binds to the small actin-binding protein, profilin. We now show that SMN and profilin II co-localise in the cytoplasm of differentiating rat PC12 cells and in neurite-like extensions, especially at their growth cones. Many components of known SMN complexes were also found in these extensions, including gemin2 (SIP-1), gemin6, gemin7 and unrip (unr-interacting protein). Coilin p80 and Sm core protein immunoreactivity, however, were seen only in the nucleus. SMN is known to associate with {beta}-actin mRNA and specific hnRNPs in axons and in neurite extensions of cultured nerve cells, and SMN also stimulates neurite outgrowth in cultures. Our results are therefore consistent with SMN complexes, rather than SMN alone, being involved in the transport of actin mRNPs along the axon as in the transport of snRNPs into the nucleus by similar SMN complexes. Antisense knockdown of profilin I and II isoforms inhibited neurite outgrowth of PC12 cells and caused accumulation of SMN and its associated proteins in cytoplasmic aggregates. BIAcore studies demonstrated a high affinity interaction of SMN with profilin IIa, the isoform present in developing neurons. Pathogenic missense mutations in SMN, or deletion of exons 5 and 7, prevented this interaction. The interaction is functional in that SMN can modulate actin polymerisation in vitro by reducing the inhibitory effect of profilin IIa. This suggests that reduced SMN in SMA might cause axonal pathfinding defects by disturbing the normal regulation of microfilament growth by profilins.

  14. Seminal Plasma Induces Ovulation in Llamas in the Absence of a Copulatory Stimulus: Role of Nerve Growth Factor as an Ovulation-Inducing Factor.

    PubMed

    Berland, Marco A; Ulloa-Leal, Cesar; Barría, Miguel; Wright, Hollis; Dissen, Gregory A; Silva, Mauricio E; Ojeda, Sergio R; Ratto, Marcelo H

    2016-08-01

    Llamas are considered to be reflex ovulators. However, semen from these animals is reported to be rich in ovulation-inducing factor(s), one of which has been identified as nerve growth factor (NGF). These findings suggest that ovulation in llamas may be elicited by chemical signals contained in semen instead of being mediated by neural signals. The present study examines this notion. Llamas displaying a preovulatory follicle were assigned to four groups: group 1 received an intrauterine infusion (IUI) of PBS; group 2 received an IUI of seminal plasma; group 3 was mated to a male whose urethra had been surgically diverted (urethrostomized male); and group 4 was mated to an intact male. Ovulation (detected by ultrasonography) occurred only in llamas mated to an intact male or given an IUI of seminal plasma and was preceded by a surge in plasma LH levels initiated within an hour after coitus or IUI. In both ovulatory groups, circulating β-NGF levels increased within 15 minutes after treatment, reaching values that were greater and more sustained in llamas mated with an intact male. These results demonstrate that llamas can be induced to ovulate by seminal plasma in the absence of copulation and that copulation alone cannot elicit ovulation in the absence of seminal plasma. In addition, our results implicate β-NGF as an important mediator of seminal plasma-induced ovulation in llamas because ovulation does not occur if β-NGF levels do not increase in the bloodstream, a change that occurs promptly after copulation with an intact male or IUI of seminal plasma. PMID:27355492

  15. Prolonged hemidiaphragmatic paresis following continuous interscalene brachial plexus block: A case report.

    PubMed

    Shinn, Helen Ki; Kim, Byung-Gun; Jung, Jong Kwon; Kwon, Hee Uk; Yang, Chunwoo; Won, Jonghun

    2016-06-01

    Interscalene brachial plexus block provides effective anesthesia and analgesia for shoulder surgery. One of the disadvantages of this technique is the risk of hemidiaphragmatic paresis, which can occur as a result of phrenic nerve block and can cause a decrease in the pulmonary function, limiting the use of the block in patients with reduced functional residual capacity or a preexisting pulmonary disease. However, it is generally transient and is resolved over the duration of the local anesthetic's action.We present a case of a patient who experienced prolonged hemidiaphragmatic paresis following a continuous interscalene brachial plexus block for the postoperative pain management of shoulder surgery, and suggest a mechanism that may have led to this adverse effect.Nerve injuries associated with peripheral nerve blocks may be caused by several mechanisms. Our findings suggest that perioperative nerve injuries can occur as a result of combined mechanical and chemical injuries. PMID:27310984

  16. Neuroprotective effects of ultrasound-guided nerve growth factor injections after sciatic nerve injury

    PubMed Central

    Li, Hong-fei; Wang, Yi-ru; Huo, Hui-ping; Wang, Yue-xiang; Tang, Jie

    2015-01-01

    Nerve growth factor (NGF) plays an important role in promoting neuroregeneration after peripheral nerve injury. However, its effects are limited by its short half-life; it is therefore important to identify an effective mode of administration. High-frequency ultrasound (HFU) is increasingly used in the clinic for high-resolution visualization of tissues, and has been proposed as a method for identifying and evaluating peripheral nerve damage after injury. In addition, HFU is widely used for guiding needle placement when administering drugs to a specific site. We hypothesized that HFU guiding would optimize the neuroprotective effects of NGF on sciatic nerve injury in the rabbit. We performed behavioral, ultrasound, electrophysiological, histological, and immunohistochemical evaluation of HFU-guided NGF injections administered immediately after injury, or 14 days later, and compared this mode of administration with intramuscular NGF injections. Across all assessments, HFU-guided NGF injections gave consistently better outcomes than intramuscular NGF injections administered immediately or 14 days after injury, with immediate treatment also yielding better structural and functional results than when the treatment was delayed by 14 days. Our findings indicate that NGF should be administered as early as possible after peripheral nerve injury, and highlight the striking neuroprotective effects of HFU-guided NGF injections on peripheral nerve injury compared with intramuscular administration. PMID:26807123

  17. Automatic segmentation of nerve structures in ultrasound images using Graph Cuts and Gaussian processes.

    PubMed

    Gil González, Julián; Álvarez, Mauricio A; Orozco, Álvaro A

    2015-01-01

    Peripheral Nerve Blocking (PNB), is a procedure used for performing regional anesthesia, that comprises the administration of anesthetic in the proximity of a nerve. Several techniques have been used with the purpose of locating nerve structures when the PNB procedure is performed: anatomical surface landmarks, elicitation of paresthesia, nerve stimulation and ultrasound imaging. Among those, ultrasound imaging has gained great attention because it is not invasive and offers an accurate location of the nerve and the structures around it. However, the segmentation of nerve structures in ultrasound images is a difficult task for the specialist, since such images are affected by echo perturbations and speckle noise. The development of systems for the automatic segmentation of nerve structures can aid the specialist for locating nerve structures accurately. In this paper we present a methodology for the automatic segmentation of nerve structures in ultrasound images. An initial step is carried out using Graph Cut segmentation in order to generate regions of interest; we then use machine learning techniques with the aim of segmenting the nerve structure; here, a specific non-linear Wavelet transform is used for the feature extraction stage, and Gaussian processes for the classification step. The methodology performance is measured in terms of accuracy and the dice coefficient. Results show that the implemented methodology can be used for automatically segmenting nerve structures. PMID:26736945

  18. Automatic segmentation of nerve structures in ultrasound images using Graph Cuts and Gaussian processes.

    PubMed

    Gil González, Julián; Álvarez, Mauricio A; Orozco, Álvaro A

    2015-01-01

    Peripheral Nerve Blocking (PNB), is a procedure used for performing regional anesthesia, that comprises the administration of anesthetic in the proximity of a nerve. Several techniques have been used with the purpose of locating