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Sample records for nerve block role

  1. Nerve Blocks

    MedlinePlus

    ... Sometimes the needle has to be inserted fairly deep to reach the nerve causing your problem. This ... understanding of the possible charges you will incur. Web page review process: This Web page is reviewed ...

  2. 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…

  3. Nerve blocks for chronic pain.

    PubMed

    Hayek, Salim M; Shah, Atit

    2014-10-01

    Nerve blocks are often performed as therapeutic or palliative interventions for pain relief. However, they are often performed for diagnostic or prognostic purposes. When considering nerve blocks for chronic pain, clinicians must always consider the indications, risks, benefits, and proper technique. Nerve blocks encompass a wide variety of interventional procedures. The most common nerve blocks for chronic pain and that may be applicable to the neurosurgical patient population are reviewed in this article. This article is an introduction and brief synopsis of the different available blocks that can be offered to a patient.

  4. Role of intercostal nerve block in reducing postoperative pain following video-assisted thoracoscopy: A randomized controlled trial

    PubMed Central

    Ahmed, Zulfiqar; Samad, Khalid; Ullah, Hameed

    2017-01-01

    Background: The main advantages of video assisted thoracoscopic surgery (VATS) include less post-operative pain, rapid recovery, less postoperative complications, shorter hospital stay and early discharge. Although pain intensity is less as compared to conventional thoracotomy but still patients experience upto moderate pain postoperatively. The objective of this study was to assess the efficacy and morphine sparing effect of intercostal nerve block in alleviating immediate post-operative pain in patients undergoing VATS. Materials and Methods: Sixty ASA I-III patients, aged between 16 to 60 years, undergoing mediastinal lymph node biopsy through VATS under general anaesthesia were randomly divided into two groups. The intercostal nerve block (ICNB group) received the block along with patient control intravenous analgesia (PCIA) with morphine, while control group received only PCIA with morphine for post-operative analgesia. Patients were followed for twenty four hours post operatively for intervention of post-operative pain in the recovery room and ward. Results: The pain was assessed using visual analogue scale (VAS) at 1, 6, 12 and 24 hours. There was a significant decrease in pain score and morphine consumption in ICNB group as compared to control group in first 6 hours postoperatively. There was no significant difference in pain scores and morphine consumption between the two groups after 6 hours. Conclusion: Patients receiving intercostal nerve block have better pain control and less morphine consumption as compared to those patients who did not receive intercostal nerve block in early (6 hours) post-operative period. PMID:28217054

  5. 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

  6. Pudendal nerve block for vaginal birth.

    PubMed

    Anderson, Deborah

    2014-01-01

    Pudendal nerve block is a safe and effective pain relief method for vaginal birth. Providing analgesia to the vulva and anus, it is used for operative vaginal birth and subsequent repair, late second stage pain relief with spontaneous vaginal birth, repair of complex lacerations, or repair of lacerations in women who are unable to achieve adequate or satisfactory pain relief during perineal repair with local anesthesia. Key to its efficacy is the knowledge of pudendal nerve anatomy, the optimal point of infiltration of local anesthetic, and an understanding of the amount of time necessary to effect adequate analgesia.

  7. 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

  8. 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.

  9. 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

  10. Physiological and pharmacologic aspects of peripheral nerve blocks.

    PubMed

    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.

  11. 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.

  12. Permanent nerve damage from inferior alveolar nerve blocks: a current update.

    PubMed

    Pogrel, M Anthony

    2012-10-01

    Permanent nerve involvement has been reported following inferior alveolar nerve blocks. This study provides an update on cases reported to one unit in the preceding six years. Lidocaine was associated with 25 percent of cases, articaine with 33 percent of cases, and prilocaine with 34 percent of cases. It does appear that inferior alveolar nerve blocks can cause permanent nerve damage with any local anesthetic, but the incidences may vary.

  13. Can We Perform Distal Nerve Block Instead of Brachial Plexus Nerve Block Under Ultrasound Guidance for Hand Surgery?

    PubMed Central

    Ince, Ilker; Aksoy, Mehmet; Celik, Mine

    2016-01-01

    Objective: Distal nerve blocks are used in the event of unsuccessful blocks as rescue techniques. The primary purpose of this study was to determine the sufficiency for anesthesia of distal nerve block without the need for deep sedation or general anesthesia. The secondary purpose was to compare block performance times, block onset times, and patient and surgeon satisfaction. Materials and Methods: Patients who underwent hand surgery associated with the innervation area of the radial and median nerves were included in the study. Thirty-four patients who were 18–65 years old and American Society of Anesthesiologists grade I–III and who were scheduled for elective hand surgery under conscious nerve block anesthesia were randomly included in an infraclavicular block group (Group I, n=17) or a radial plus median block group (Group RM, n=17). The block performance time, block onset time, satisfaction of the patient and surgeon, and number of fentanyl administrations were recorded. Results: The numbers of patients who needed fentanyl administration and conversion to general anesthesia were the same in Group I and Group RM and there was no statistically significant difference (p>0.05). The demographics, surgery times, tourniquet times, block perfomance times, and patient and surgeon satisfaction of the groups were similar and there were no statistically significant differences (p>0.05). There was a statistically significant difference in block onset times between the groups (p<0.05). Conclusions: Conscious hand surgery can be performed under distal nerve block anesthesia safely and successfully. PMID:28149139

  14. 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

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

    PubMed

    Patel, Yogi A; Butera, Robert J

    2015-06-01

    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.

  16. Kilohertz Electrical Stimulation Nerve Conduction Block: Effects of Electrode Surface Area.

    PubMed

    Patel, Yogi A; Kim, Brian S; Rountree, William S; Butera, Robert J

    2017-03-17

    Kilohertz electrical stimulation (KES) induces repeatable and reversible conduction block of nerve activity and is a potential therapeutic option for various diseases and disorders resulting from pathological or undesired neurological activity. However successful translation of KES nerve block to clinical applications is stymied by many unknowns such as the relevance of the onset response, acceptable levels of waveform contamination, and optimal electrode characteristics. We investigated the role of electrode geometric surface area on the KES nerve block threshold using 20 and 40 kHz current-controlled sinusoidal KES. Electrodes were electrochemically characterized and used to characterize typical KES waveforms and electrode charge characteristics. KES nerve block amplitudes, onset duration, and recovery of normal conduction after delivery of KES were evaluated along with power requirements for effective KES nerve block. Results from this investigation demonstrate that increasing electrode geometric surface area provides for a more power efficient KES nerve block. Reductions in block threshold by increased electrode surface area were found to be KESfrequency dependent, with block thresholds and average power consumption reduced by >2x with 20 kHz KES waveforms and >3x for 40 kHz KES waveforms.

  17. Essential regional nerve blocks for the dermatologist: Part 2.

    PubMed

    Davies, T; Karanovic, S; Shergill, B

    2014-12-01

    Following on from Part 1 of the series (regional nerve blocks for the face and scalp), we guide the clinician through the anatomy and cutaneous innervation of the digits, wrist and ankle, providing a practical step-by-step guide to regional nerve blockade of these areas.

  18. Essential regional nerve blocks for the dermatologist: part 1.

    PubMed

    Davies, T; Karanovic, S; Shergill, B

    2014-10-01

    The aim of this two-part series is to provide an up-to-date review of essential regional nerve blocks for dermatological practice. In Part 1, we give a concise overview of local anaesthetics and their potential complications, as well as the relevant anatomy and cutaneous innervation of the face and scalp. This culminates in a step-by-step practical guide to performing each nerve block.

  19. 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

  20. Role of addition of dexamethasone to lignocaine 2% with adrenaline in dental nerve blocks for third molar surgery: A prospective randomized control trial

    PubMed Central

    Deo, Saroj Prasad

    2016-01-01

    Context: Dexamethasone has been frequently used in oral surgical procedure and accepted by oral and maxillofacial surgeon community worldwide. However, this is the first clinical trial that used dexamethasone as adjuvant with lignocaine in dental nerve block (DNB). Aims: The purpose of this double-blind, randomized control trial (RCT) was to compare the effect of dexamethasone with normal saline (NS) in a lignocaine DNB. Settings and Design: This prospective, double-blind, RCT was carried out after obtaining approval from the Institutional Ethical Committee. Subjects and Methods: In forty patients, the present placebo-controlled clinical trial was conducted; allocated randomly into two groups: study group (SG) or control group (CG). The single-dose submucosal dexamethasone or NS injection was administered immediately after 2% lignocaine with epinephrine 1:2,00,000 nerves block during mandibular third molar surgery (TMS). Visual analog scale score, number, and exact time nonsteroidal anti-inflammatory drugs were administered were used to measure postoperative analgesia in 2nd and 7th days. Statistical Analysis Used: All the data were entered into the Spreadsheet (Excel, Microsoft) and Chi-square test, Mann–Whitney U-test, Student's paired and unpaired t-test, and Fisher exact test were used. Results: This study found maximum duration of DNB in SG was 248.88 min and in CG was 175.44 min, whereas minimum duration in SG was 197 min and in CG was 140.78 min. Conclusions: Dexamethasone prolongs the action of lignocaine 2% in DNB for TMS. PMID:28299268

  1. Kilohertz frequency nerve block enhances anti-inflammatory effects of vagus nerve stimulation

    PubMed Central

    Patel, Yogi A.; Saxena, Tarun; Bellamkonda, Ravi V.; Butera, Robert J.

    2017-01-01

    Efferent activation of the cervical vagus nerve (cVN) dampens systemic inflammatory processes, potentially modulating a wide-range of inflammatory pathological conditions. In contrast, afferent cVN activation amplifies systemic inflammatory processes, leading to activation of the hypothalamic-pituitary-adrenal (HPA) axis, the sympathetic nervous system through the greater splanchnic nerve (GSN), and elevation of pro-inflammatory cytokines. Ideally, to clinically implement anti-inflammatory therapy via cervical vagus nerve stimulation (cVNS) one should selectively activate the efferent pathway. Unfortunately, current implementations, in animal and clinical investigations, activate both afferent and efferent pathways. We paired cVNS with kilohertz electrical stimulation (KES) nerve block to preferentially activate efferent pathways while blocking afferent pathways. Selective efferent cVNS enhanced the anti-inflammatory effects of cVNS. Our results demonstrate that: (i) afferent, but not efferent, cVNS synchronously activates the GSN in a dose-dependent manner; (ii) efferent cVNS enabled by complete afferent KES nerve block enhances the anti-inflammatory benefits of cVNS; and (iii) incomplete afferent KES nerve block exacerbates systemic inflammation. Overall, these data demonstrate the utility of paired efferent cVNS and afferent KES nerve block for achieving selective efferent cVNS, specifically as it relates to neuromodulation of systemic inflammation. PMID:28054557

  2. Ultrasonography Evaluation of Vulnerable Vessels Around Cervical Nerve Roots During Selective Cervical Nerve Root Block

    PubMed Central

    2017-01-01

    Objective To evaluate the prevalence of vulnerable blood vessels around cervical nerve roots before cervical nerve root block in the clinical setting. Methods This retrospective study included 74 patients with cervical radiculopathy who received an ultrasonography-guided nerve block at an outpatient clinic from July 2012 to July 2014. Before actual injection of the steroid was performed, we evaluated the vulnerable blood vessels around each C5, C6, and C7 nerve root of each patient's painful side, with Doppler ultrasound. Results Out of 74 cases, the C5 level had 2 blood vessels (2.7%), the C6 level had 4 blood vessels (5.45%), and the C7 level had 6 blood vessels (8.11%) close to each targeted nerve root. Moreover, the C5 level had 2 blood vessels (2.7%), the C6 level 5 blood vessels (6.75%), and the C7 level had 4 blood vessels (5.45%) at the site of an imaginary needle's projected pathway to the targeted nerve root, as revealed by axial transverse ultrasound imaging with color Doppler imaging. In total, the C5 level had 4 blood vessels (5.45%), the C6 level 9 blood vessels (12.16%), and the C7 level 10 had blood vessels (13.51%) either at the targeted nerve root or at the site of the imaginary needle's projected pathway to the targeted nerve root. There was an unneglectable prevalence of vulnerable blood vessels either at the targeted nerve root or at the site of the needle' projected pathway to the nerve root. Also, it shows a higher prevalence of vulnerable blood vessels either at the targeted nerve root or at the site of an imaginary needle's projected pathway to the nerve root as the spinal nerve root level gets lower. Conclusion To prevent unexpected critical complications involving vulnerable blood vessel injury during cervical nerve root block, it is recommended to routinely evaluate for the presence of vulnerable blood vessels around each cervical nerve root using Doppler ultrasound imaging before the cervical nerve root block, especially for the lower

  3. Bupivacaine and ropivacaine: comparative effects on nerve conduction block.

    PubMed

    Bariskaner, H; Ayaz, M; Guney, F B; Dalkilic, N; Guney, O

    2007-06-01

    Unlike other drugs which act in the region of the synapse, local anesthetics are agents that reversibly block the generation and conduction of nerve impulses along a nerve fiber. This study aims to investigate the comparative inhibitions of bupivacaine and ropivacaine on the frog sciatic nerve. Isolated nerves were transferred to the nerve chamber which includes Ringer's solution. The nerves were stimulated by standard square wave pulse protocols and the responses were recorded with conventional systems. Bupivacaine (n = 8) and ropivacaine (n = 8) were administered in the nerve chamber bath with cumulative concentrations (10(-9) to 10(-3) M) and the effects were monitored for variable time periods (5, 10 and 15 min). Both bupivacaine and ropivacaine significantly depressed the compound action potential (CAP) parameters in a dose-dependent (p < 0.05) and reversible manner. Difference in the effects of these two drugs was detectable only when the dose (> or =10(-5) M) and exposure time (15 min) were increased. Percent inhibitions in maximum derivatives and latency-period measurements have shown that ropivacaine is not only fast but also much more powerful in conduction block for longer and higher doses. Bupivacaine, on the other hand, is effective in the group of fibers with relatively slower conduction velocity for all the measured doses and time periods. In conclusion, ropivacaine has a sensory specific side of action, when compared with the bupivacaine.

  4. Ultrasound and electrical nerve stimulation-guided S1 nerve root block.

    PubMed

    Sato, Masaki; Mikawa, Yasuhito; Matuda, Akiko

    2013-10-01

    A selective lumbosacral nerve root block is generally is performed under X-ray fluoroscopy, which has the disadvantage of radiation exposure and the need for fluoroscopy equipment. In this study, we assessed the effectiveness of ultrasound and nerve stimulation-guided S1 nerve root block on 37 patients with S1 radicular syndrome. With the patient in a prone position, an ultrasound scan was performed by placing the probe parallel to the body axis. The needle was pointed slightly medial from the lateral side of the probe and advanced toward a hyperechoic area in the sacral foramina with ultrasound guidance. Contrast medium was then injected and its dispersion confirmed by fluoroscopy. The acquired contrast images were classified into intraneural, perineural, and paraneural patterns. The significance of differences in the effect of the block among the contrast image patterns was analyzed. After nerve block, decreased sensation at the S1 innervated region and pain relief was achieved in all patients. No significant difference was noted in the effect of the block between perineural and paraneural patterns. In conclusion, this technique provided reliable S1 nerve root block in patients with S1 radicular syndrome and minimized radiation exposure.

  5. An audit of peripheral nerve blocks for hand surgery.

    PubMed Central

    Porter, J. M.; Inglefield, C. J.

    1993-01-01

    A prospective audit of 140 median, radial and ulnar blocks, given for 70 hand operations is described. The surgery was completed successfully in every patient. A further injection of local anaesthetic was required in 13 operations. Four patients experienced severe tourniquet pain. The results of the audit have shown that if a careful technique is used, a wide range of minor hand operations can be performed under regional nerve block. PMID:8215147

  6. Nerve Stimulator versus Ultrasound-Guided Femoral Nerve Block; a Randomized Clinical Trial

    PubMed Central

    Forouzan, Arash; Masoumi, Kambiz; Motamed, Hasan; Gousheh, Mohammad Reza; Rohani, Akram

    2017-01-01

    Introduction: Pain control is the most important issue in emergency department management of patients with femoral bone fractures. The present study aimed to compare the procedural features of ultrasonography and nerve stimulator guided femoral nerve block in this regard. Method: In this randomized clinical trial, patients with proximal femoral fractures presenting to emergency department were randomly divided into two groups of ultrasonography or nerve stimulator guided femoral block and compared regarding success rate, procedural time, block time, and need for rescue doses of morphine sulfate, using SPSS 20. Results: 50 patients were randomly divided into two groups of 25 (60% male). The mean age of studied patients was 35.14 ± 12.95 years (19 – 69). The two groups were similar regarding age (p= 0.788), sex (p = 0.564), and initial pain severity (p = 0.513). In 2 cases of nerve stimulator guided block, loss of pinprick sensation did not happen within 30 minutes of injection (success rate: 92%; p = 0.490). Ultrasonography guided nerve block cases had significantly lower procedural time (8.06 ± 1.92 vs 13.60 ± 4.56 minutes; p < 0.001) and lower need for rescue doses of opioid (2.68 ± 0.74 vs 5.28 ± 1.88 minutes; p < 0.001). Conclusion: Ultrasonography and nerve stimulator guided femoral block had the same success rate and block duration. However, the ultrasonography guided group had lower procedure time and lower need for rescue doses of morphine sulfate. Therefore, ultrasonography guided femoral block could be considered as an available, safe, rapid, and efficient method for pain management of femoral fracture in emergency department.

  7. Use of digital nerve blocks to provide anaesthetic relief.

    PubMed

    Summers, Anthony

    2011-09-01

    This article discusses the various techniques that nurses can use to perform digital nerve blocks, which are some of the most common procedures undertaken by emergency practitioners treating patients with finger injuries. In covering the advantages and disadvantages of each technique, it focuses primarily on the digits of the hand, but the techniques can also be performed on toes.

  8. 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.

  9. Electrical conduction block in large nerves: high-frequency current delivery in the nonhuman primate.

    PubMed

    Ackermann, D Michael; Ethier, Christian; Foldes, Emily L; Oby, Emily R; Tyler, Dustin; Bauman, Matt; Bhadra, Niloy; Miller, Lee; Kilgore, Kevin L

    2011-06-01

    Recent studies have made significant progress toward the clinical implementation of high-frequency conduction block (HFB) of peripheral nerves. However, these studies were performed in small nerves, and questions remain regarding the nature of HFB in large-diameter nerves. This study in nonhuman primates shows reliable conduction block in large-diameter nerves (up to 4.1 mm) with relatively low-threshold current amplitude and only moderate nerve discharge prior to the onset of block.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. Induction of vasospastic attacks despite digital nerve block in Raynaud's disease and phenomenon.

    PubMed

    Freedman, R R; Mayes, M D; Sabharwal, S C

    1989-10-01

    Using a combination of environmental and local cooling, we induced vasospastic attacks of Raynaud's phenomenon in nine of 11 patients with idiopathic Raynaud's disease and in eight of 10 patients with scleroderma. Attacks were defined as occurring if two of the possible three color changes (pallor, cyanosis, and rubor) occurred, and serial photographs were scored by three independent raters. Two fingers on one hand were anesthetized by local injection of lidocaine, and the effectiveness of nerve blocks was verified by plethysmography. The frequency of vasospastic attacks in nerve-blocked fingers was not significantly different from that in the corresponding intact fingers on the contralateral hand. These findings show that the vasospastic attacks of Raynaud's disease and phenomenon can occur without the involvement of efferent digital nerves and argue against the etiologic role of sympathetic hyperactivity.

  15. Effectiveness of Greater Occipital Nerve Blocks in Migraine Prophylaxis

    PubMed Central

    İNAN, Nurten; İNAN, Levent E.; COŞKUN, Özlem; TUNÇ, Tuğba; İLHAN, Mustafa

    2016-01-01

    Introduction Peripheral nerve blocks have been used in primary headache treatment since a long time. In this study, we aimed to examine the efficiency of greater occipital nerve (GON) block in migraine prophylaxis. Methods Data from migraine without aura patients who had GON block were collected and divided into two groups: Group PGON (n=25), which included patients who were under medical prophylaxis and had GON block, and Group GON (n=53), which included patients who had only GON blocks. Migraine was diagnosed using International Headache Society (IHS) classification. Data of 78 patients were analyzed. Headache attack frequency, headache duration, and severity were compared between and within groups in a 3-month follow-up period. Results The decrease in headache parameters after GON block in both groups was significantly similar. Headache attack frequency decreased from 15.73±7.21 (pretreatment) to 4.52±3.61 (3rd month) in Group GON and from 13.76±8.07 to 3.28±2.15 in Group PGON (p<0.05). Headache duration decreased from 18.51±9.43 to 8.02±5.58 at 3rd month in Group GON and from 15.20±9.16 to 7.20±4.16 in Group PGON (p<0.05). Headache severity decreased from 8.26±1.32 to 5.16±2.64 in Group GON and from 8.08±0.90 to 5.96±1.20 in Group PGON (p<0.05). There was no statistically significant difference between the groups in 3rd month after treatment (p>0.05). Conclusion This study showed significant decreases in headache parameters in both groups. As GON blocks were performed in patients unresponsive to medical prophylaxis, a decrease in the headache parameters in Group PGON similar to that in Group GON can be attributed to GON blocks. Consequently, these results show that repeated GON blocks with local anesthetic can be an effective alternative treatment in migraine patients who are unresponsive to medical prophylaxis or who do not prefer to use medical prophylaxis. PMID:28360765

  16. Fall Risk Associated with Continuous Peripheral Nerve Blocks Following Knee and Hip Arthroplasty.

    PubMed

    Finn, Daphna M; Agarwal, Rishi R; Ilfeld, Brian M; Madison, Sarah J; Ball, Scott T; Ferguson, Eliza J; Morgan, Anya C; Morris, Beverly A

    2016-01-01

    Combined scientific advances in pharmaceutical agents, perineural blocks, and pump delivery capabilities such as those used with continuous peripheral nerve blocks have demonstrated advantages in pain management for patients undergoing joint arthroplasty. This report documents the incidence of falls increased after the implementation of a continuous peripheral nerve block program for patients undergoing knee and hip arthroplasty in an academic medical center.

  17. 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

  18. 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.

  19. The role of the superior laryngeal nerve in esophageal reflexes.

    PubMed

    Lang, I M; Medda, B K; Jadcherla, S; Shaker, R

    2012-06-15

    The aim of this study was to determine the role of the superior laryngeal nerve (SLN) in the following esophageal reflexes: esophago-upper esophageal sphincter (UES) contractile reflex (EUCR), esophago-lower esophageal sphincter (LES) relaxation reflex (ELIR), secondary peristalsis, pharyngeal swallowing, and belch. Cats (N = 43) were decerebrated and instrumented to record EMG of the cricopharyngeus, thyrohyoideus, geniohyoideus, and cricothyroideus; esophageal pressure; and motility of LES. Reflexes were activated by stimulation of the esophagus via slow balloon or rapid air distension at 1 to 16 cm distal to the UES. Slow balloon distension consistently activated EUCR and ELIR from all areas of the esophagus, but the distal esophagus was more sensitive than the proximal esophagus. Transection of SLN or proximal recurrent laryngeal nerves (RLN) blocked EUCR and ELIR generated from the cervical esophagus. Distal RLN transection blocked EUCR from the distal cervical esophagus. Slow distension of all areas of the esophagus except the most proximal few centimeters activated secondary peristalsis, and SLN transection had no effect on secondary peristalsis. Slow distension of all areas of the esophagus inconsistently activated pharyngeal swallows, and SLN transection blocked generation of pharyngeal swallows from all levels of the esophagus. Slow distension of the esophagus inconsistently activated belching, but rapid air distension consistently activated belching from all areas of the esophagus. SLN transection did not block initiation of belch but blocked one aspect of belch, i.e., inhibition of cricopharyngeus EMG. Vagotomy blocked all aspects of belch generated from all areas of esophagus and blocked all responses of all reflexes not blocked by SLN or RLN transection. In conclusion, the SLN mediates all aspects of the pharyngeal swallow, no portion of the secondary peristalsis, and the EUCR and ELIR generated from the proximal esophagus. Considering that SLN is not

  20. Treatment of great auricular neuralgia with real-time ultrasound-guided great auricular nerve block

    PubMed Central

    Jeon, Younghoon; Kim, Saeyoung

    2017-01-01

    Abstract Rationale: The great auricular nerve can be damaged by the neck surgery, tumor, and long-time pressure on the neck. But, great auricular neuralgia is very rare condition. It was managed by several medication and landmark-based great auricular nerve block with poor prognosis. Patient concerns: A 25-year-old man presented with a pain in the left lateral neck and auricle. Diagnosis: He was diagnosed with great auricular neuralgia. Interventions: His pain was not reduced by medication. Therefore, the great auricular nerve block with local anesthetics and steroid was performed under ultrasound guidance. Outcomes: Ultrasound guided great auricular nerve block alleviated great auricular neuralgia. Lessons: This medication-resistant great auricular neuralgia was treated by the ultrasound guided great auricular nerve block with local anesthetic agent and steroid. Therefore, great auricular nerve block can be a good treatment option of medication resistant great auricular neuralgia. PMID:28328811

  1. 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

  2. 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

  3. The Anatomic Relationship of the Tibial Nerve to the Common Peroneal Nerve in the Popliteal Fossa: Implications for Selective Tibial Nerve Block in Total Knee Arthroplasty

    PubMed Central

    Silverman, Eric R.; Vydyanathan, Amaresh; Gritsenko, Karina; Shaparin, Naum; Singh, Nair; Downie, Sherry A.

    2017-01-01

    Background. A recently described selective tibial nerve block at the popliteal crease presents a viable alternative to sciatic nerve block for patients undergoing total knee arthroplasty. In this two-part investigation, we describe the effects of a tibial nerve block at the popliteal crease. Methods. In embalmed cadavers, after the ultrasound-guided dye injection the dissection revealed proximal spread of dye within the paraneural sheath. Consequentially, in the clinical study twenty patients scheduled for total knee arthroplasty received the ultrasound-guided selective tibial nerve block at the popliteal crease, which also resulted in proximal spread of local anesthetic. A sensorimotor exam was performed to monitor the effect on the peroneal nerve. Results. In the cadaver study, dye was observed to spread proximal in the paraneural sheath to reach the sciatic nerve. In the clinical observational study, local anesthetic was observed to spread a mean of 4.7 + 1.9 (SD) cm proximal to popliteal crease. A negative correlation was found between the excess spread of local anesthetic and bifurcation distance. Conclusions. There is significant proximal spread of local anesthetic following tibial nerve block at the popliteal crease with possibility of the undesirable motor blocks of the peroneal nerve. PMID:28260964

  4. Neurotoxicity Questions Regarding Common Peripheral Nerve Block Adjuvants in Combination with Local Anesthetics

    PubMed Central

    Knight, Joshua B.; Schott, Nicholas J.; Kentor, Michael L.; Williams, Brian A.

    2015-01-01

    Purpose of Review Outline the analgesic role of perineural adjuvants for local anesthetic nerve block injections, and evaluate current knowledge regarding whether adjuvants modulate the neurocytologic properties of local anesthetics. Recent Findings Perineural adjuvant medications such as dexmedetomidine, clonidine, buprenorphine, dexamethasone, and midazolam play unique analgesic roles. The dosing of these medications to prevent neurotoxicity is characterized in various cellular and in vivo models. Much of this mitigation may be via reducing the dose of local anesthetic used while achieving equal or superior analgesia. Dose-concentration animal models have shown no evidence of deleterious effects. Clinical observations regarding blocks with combined bupivacaine-clonidine-buprenorphine-dexamethasone have shown beneficial effects on block duration and rebound pain without long-term evidence of neurotoxicity. In vitro and in vivo studies of perineural clonidine and dexmedetomidine show attenuation of perineural inflammatory responses generated by local anesthetics. Summary Dexmedetomidine added as a peripheral nerve blockade adjuvant improves block duration without neurotoxic properties. The combined adjuvants clonidine, buprenorphine, and dexamethasone do not appear to alter local anesthetic neurotoxicity. Midazolam significantly increases local anesthetic neurotoxicity in vitro, but when combined with clonidine-buprenorphine-dexamethasone (sans local anesthetic) produces no in vitro or in vivo neurotoxicity. Further larger-species animal testing and human trials will be required to reinforce the clinical applicability of these findings. PMID:26207854

  5. Efficacy of Bilateral Mental Nerve Block with Bupivacaine for Postoperative Pain Control in Mandibular Parasymphysis Fractures

    PubMed Central

    Mesgarzadeh, Ali Hossein; Afsari, Hosein; Pourkhamne, Sohrab; Shahamfar, Mohamadreza

    2014-01-01

    Background and aims. Postoperative pain control is extremely important for both patients and surgeons; in this context, long-acting local anesthesia can play an important role after open reduction of maxillofacial fractures. The purpose of this study was to evaluate the effect of bilateral mental nerve block with bupivacaine on postoperative pain control in mandibular symphyseal fractures. Materials and methods. Fifty patients with pure mandibular symphyseal fractures were studied in two control and study groups. In contrast to the control group, the study group received bilateral mental nerve block with bupivacaine postoperatively. Patients were examined in relation to pain severity and opioid analgesic drug need sequences. Results. The study group needed significantly less opioid than the control group (P<0.01, U=141). The control and study groups were different in first opioid administration time. The control and study groups received first opioid dose in 0-2 and 2-4 hours, respectively. Conclusion. Bilateral mental nerve blocks with bupivacaine can reduce opioid analgesic need and it has a positive effect on postoperative pain control in mandibular symphyseal fractures. PMID:25346837

  6. Different Learning Curves for Axillary Brachial Plexus Block: Ultrasound Guidance versus Nerve Stimulation

    PubMed Central

    Luyet, C.; Schüpfer, G.; Wipfli, M.; Greif, R.; Luginbühl, M.; Eichenberger, U.

    2010-01-01

    Little is known about the learning of the skills needed to perform ultrasound- or nerve stimulator-guided peripheral nerve blocks. The aim of this study was to compare the learning curves of residents trained in ultrasound guidance versus residents trained in nerve stimulation for axillary brachial plexus block. Ten residents with no previous experience with using ultrasound received ultrasound training and another ten residents with no previous experience with using nerve stimulation received nerve stimulation training. The novices' learning curves were generated by retrospective data analysis out of our electronic anaesthesia database. Individual success rates were pooled, and the institutional learning curve was calculated using a bootstrapping technique in combination with a Monte Carlo simulation procedure. The skills required to perform successful ultrasound-guided axillary brachial plexus block can be learnt faster and lead to a higher final success rate compared to nerve stimulator-guided axillary brachial plexus block. PMID:21318138

  7. 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

  8. Adductor canal block versus femoral nerve block combined with sciatic nerve block as an anesthetic technique for hindfoot and ankle surgery

    PubMed Central

    Joe, Han Bum; Choo, Ho Sik; Yoon, Ji Sang; Oh, Sang Eon; Cho, Jae Ho; Park, Young Uk

    2016-01-01

    Abstract Background: A femoral nerve block (FNB) in combination with a sciatic nerve block (SNB) is commonly used for anesthesia and analgesia in patients undergoing hindfoot and ankle surgery. The effects of FNB on motor function, related fall risk, and rehabilitation are controversial. An adductor canal block (ACB) potentially spares motor fibers in the femoral nerve, but the comparative effect on hindfoot and ankle surgeries between the 2 approaches is not yet well defined. We hypothesized that compared to FNB, ACB would cause less weakness in the quadriceps and produce similar pain scores during and after the operation. Methods: Sixty patients scheduled for hindfoot and ankle surgeries (arthroscopy, Achilles tendon surgery, or medial ankle surgery) were stratified randomized for each surgery to receive an FNB (FNB group) or an ACB (ACB group) combined with an SNB. The primary outcome was the visual analog scale (VAS) pain score at each stage. Secondary outcomes included quadriceps strength, time profiles (duration of the block procedure, time to full anesthesia and time to full recovery), patients’ analgesic requirements, satisfaction, and complications related to peripheral nerve blocks such as falls, neurologic symptoms, and local anesthetic systemic toxicity were evaluated. The primary outcome was tested for the noninferiority of ACB to FNB, and the other outcomes were tested for the superiority of each variable between the groups. Results: A total of 31 patients received an ACB and 29 received an FNB. The VAS pain scores of the ACB group were not inferior during and after the operation compared to those of the FNB group. At 30 minutes and 2 hours after anesthesia, patients who received an ACB had significantly higher average dynamometer readings than those who received a FNB (34.2 ± 20.4 and 30.4 ± 23.7 vs 1.7 ± 3.7 and 2.3 ± 7.4, respectively), and the results were similar at 24 and 48 hours after anesthesia. There were no differences

  9. Magnetic resonance neurography-guided nerve blocks for the diagnosis and treatment of chronic pelvic pain syndrome.

    PubMed

    Fritz, Jan; Chhabra, Avneesh; Wang, Kenneth C; Carrino, John A

    2014-02-01

    Magnetic resonance (MR) neurography - guided nerve blocks and injections describe a techniques for selective percutaneous drug delivery, in which limited MR neurography and interventional MR imaging are used jointly to map and target specific pelvic nerves or muscles, navigate needles to the target, visualize the injected drug and detect spread to confounding structures. The procedures described, specifically include nerve blocks of the obturator nerve, lateral femoral cutaneous nerve, pudendal nerve, posterior femoral cutaneous nerve, sciatic nerve, ganglion impar, sacral spinal nerve, and injection into the piriformis muscle.

  10. Characterization of high capacitance electrodes for the application of direct current electrical nerve block

    PubMed Central

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

    2015-01-01

    Direct current (DC) can briefly produce a reversible nerve conduction block in acute experiments. However, irreversible reactions at the electrode–tissue interface have prevented its use in both acute and chronic settings. A high capacitance material (platinum black) using a charge-balanced waveform was evaluated to determine whether brief DC block (13 s) could be achieved repeatedly (>100 cycles) without causing acute irreversible reduction in nerve conduction. Electrochemical techniques were used to characterize the electrodes to determine appropriate waveform parameters. In vivo experiments on DC motor conduction block of the rat sciatic nerve were performed to characterize the acute neural response to this novel nerve block system. Complete nerve motor conduction block of the rat sciatic nerve was possible in all experiments, with the block threshold ranging from −0.15 to −3.0 mA. DC pulses were applied for 100 cycles with no nerve conduction reduction in four of the six platinum black electrodes tested. However, two of the six electrodes exhibited irreversible conduction degradation despite charge delivery that was within the initial Q (capacitance) value of the electrode. Degradation of material properties occurred in all experiments, pointing to a possible cause of the reduction in nerve conduction in some platinum black experiments. PMID:26358242

  11. Characterization of high capacitance electrodes for the application of direct current electrical nerve block.

    PubMed

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

    2016-01-01

    Direct current (DC) can briefly produce a reversible nerve conduction block in acute experiments. However, irreversible reactions at the electrode-tissue interface have prevented its use in both acute and chronic settings. A high capacitance material (platinum black) using a charge-balanced waveform was evaluated to determine whether brief DC block (13 s) could be achieved repeatedly (>100 cycles) without causing acute irreversible reduction in nerve conduction. Electrochemical techniques were used to characterize the electrodes to determine appropriate waveform parameters. In vivo experiments on DC motor conduction block of the rat sciatic nerve were performed to characterize the acute neural response to this novel nerve block system. Complete nerve motor conduction block of the rat sciatic nerve was possible in all experiments, with the block threshold ranging from -0.15 to -3.0 mA. DC pulses were applied for 100 cycles with no nerve conduction reduction in four of the six platinum black electrodes tested. However, two of the six electrodes exhibited irreversible conduction degradation despite charge delivery that was within the initial Q (capacitance) value of the electrode. Degradation of material properties occurred in all experiments, pointing to a possible cause of the reduction in nerve conduction in some platinum black experiments .

  12. A Novel CT-Guided Transpsoas Approach to Diagnostic Genitofemoral Nerve Block and Ablation

    PubMed Central

    Parris, David; Fischbein, Nancy; Mackey, Sean; Carroll, Ian

    2010-01-01

    Background Inguinal hernia repair is associated with a high incidence of chronic postsurgical pain. This pain may be caused by injury to the iliohypogastric, ilioinguinal, or genitofemoral nerves. It is often difficult to identify the specific source of the pain, in part, because these nerves are derived from overlapping nerve roots and closely colocalize in the area of surgery. It is therefore technically difficult to selectively block these nerves individually proximal to the site of surgical injury. In particular, the genitofemoral nerve is retroperitoneal before entering the inguinal canal, a position that puts anterior approaches to the proximal nerve at risk of transgressing into the peritoneum. We report a computed tomography (CT)-guided transpsoas technique to selectively block the genitofemoral nerve for both diagnostic and therapeutic purposes while avoiding injury to the nearby ureter and intestines. Case A 39-year-old woman with chronic lancinating right groin pain after inguinal hernia repair underwent multiple pharmacologic interventions and invasive procedures without relief. Using CT and Stimuplex nerve stimulator guidance, the genitofemoral nerve was localized on the anterior surface of the psoas muscle and a diagnostic block with local anesthetic block was performed. The patient had immediate relief of her symptoms for 36 hours, confirming the diagnosis of genitofemoral neuralgia. She subsequently underwent CT-guided radiofrequency and phenol ablation of the genitofemoral nerve but has not achieved long-term analgesia. Conclusion CT-guided transpsoas genitofemoral nerve block is a viable option for safely and selectively blocking the genitofemoral nerve for diagnostic or therapeutic purposes proximal to injury caused by inguinal surgery. PMID:20546515

  13. Femoral versus Multiple Nerve Blocks for Analgesia after Total Knee Arthroplasty

    PubMed Central

    Stav, Anatoli; Reytman, Leonid; Sevi, Roger; Stav, Michael Yohay; Powell, Devorah; Dor, Yanai; Dudkiewicz, Mickey; Bayadse, Fuaz; Sternberg, Ahud; Soudry, Michael

    2017-01-01

    Background The PROSPECT (Procedure-Specific Postoperative Pain Management) Group recommended a single injection femoral nerve block in 2008 as a guideline for analgesia after total knee arthroplasty. Other authors have recommended the addition of sciatic and obturator nerve blocks. The lateral femoral cutaneous nerve is also involved in pain syndrome following total knee arthroplasty. We hypothesized that preoperative blocking of all four nerves would offer superior analgesia to femoral nerve block alone. Methods This is a prospective, randomized, controlled, and observer-blinded clinical study. A total of 107 patients were randomly assigned to one of three groups: a femoral nerve block group, a multiple nerve block group, and a control group. All patients were treated postoperatively using patient-controlled intravenous analgesia with morphine. Pain intensity at rest, during flexion and extension, and morphine consumption were compared between groups over three days. Results A total of 90 patients completed the study protocol. Patients who received multiple nerve blocks experienced superior analgesia and had reduced morphine consumption during the postoperative period compared to the other two groups. Pain intensity during flexion was significantly lower in the “blocks” groups versus the control group. Morphine consumption was significantly higher in the control group. Conclusions Pain relief after total knee arthroplasty immediately after surgery and on the first postoperative day was significantly superior in patients who received multiple blocks preoperatively, with morphine consumption significantly lower during this period. A preoperative femoral nerve block alone produced partial and insufficient analgesia immediately after surgery and on the first postoperative day. (Clinical trial registration number (NIH): NCT01303120) PMID:28178436

  14. 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

  15. 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.

  16. Effect of differential nerve block on inhibition of the monosynaptic reflex by vibration in man

    PubMed Central

    Moddel, G.; Best, B.; Ashby, P.

    1977-01-01

    The differential nerve block produced by ischaemia has been used in an attempt to identify the afferent nerve fibres responsible for vibratory inhibition of the monosynaptic reflex in man. It is concluded that the inhibition arises mainly from receptors in the lower leg and is carried by myelinated afferent fibres larger than A-delta. PMID:599354

  17. Suprascapular nerve block in chronic shoulder pain: are the radiologists better?

    PubMed Central

    Shanahan, E; Smith, M; Wetherall, M; Lott, C; Slavotinek, J; FitzGerald, O; Ahern, M

    2004-01-01

    Background: Suprascapular nerve block is a safe and effective treatment for chronic shoulder pain in arthritis, which can be performed either by direct imaging (CT guided) or in the clinic using anatomical landmarks to determine needle placement. Objective: To compare a CT guided versus an anatomical landmark approach in a randomised, single blind trial examining the efficacy of suprascapular nerve block for shoulder pain in patients with degenerative joint/rotator cuff disease. Methods: 67 patients with chronic shoulder pain from degenerative disease participated in the trial. 77 shoulders were randomised. The group randomised to receive the block through the anatomical landmark approach received a single suprascapular nerve block. Those in the CT guided group received an injection of methylprednisolone acetate and a smaller volume of bupivacaine around the suprascapular nerve. The patients were followed up for 12 weeks by a "blinded" observer and reviewed at weeks 1, 4, and 12 after the injection. Results: Significant improvements were seen in all pain scores and disability in the shoulders receiving both types of nerve block, with no significant differences in the improvement in pain and disability between the two approaches at any time. Improvements in pain and disability scores were clinically and statistically significant. No significant adverse effects occurred in either group. Patient satisfaction scores for pain relief using either approach were high. Conclusion: The CT guided control and landmark approaches to performing suprascapular nerve blocks result in similar significant and prolonged pain and disability reductions; both approaches are safe. PMID:15308514

  18. 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.

  19. Medial antebrachial cutaneous nerve injury after brachial plexus block: two case reports.

    PubMed

    Jung, Mi Jin; Byun, Ha Young; Lee, Chang Hee; Moon, Seung Won; Oh, Min-Kyun; Shin, Heesuk

    2013-12-01

    Medial antebrachial cutaneous (MABC) nerve injury associated with iatrogenic causes has been rarely reported. Local anesthesia may be implicated in the etiology of such injury, but has not been reported. Two patients with numbness and painful paresthesia over the medial aspect of the unilateral forearm were referred for electrodiagnostic study, which revealed MABC nerve lesion in each case. The highly selective nature of the MABC nerve injuries strongly suggested that they were the result of direct nerve injury by an injection needle during previous brachial plexus block procedures. Electrodiagnostic studies can be helpful in evaluating cases of sensory disturbance after local anesthesia. To our knowledge, these are the first documented cases of isolated MABC nerve injury following ultrasound-guided axillary brachial plexus block.

  20. 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

  1. Primary Payer Status is Associated with the Use of Nerve Block Placement for Ambulatory Orthopedic Surgery

    PubMed Central

    Tighe, Patrick J.; Brennan, Meghan; Moser, M.; Boezaart, Andre P.; Bihorac, Azra

    2012-01-01

    Introduction Although more than 30 million patients in the United States undergo ambulatory surgery each year, it remains unclear what percentage of these patients receive a perioperative nerve block. We reviewed data from the 2006 National Survey of Ambulatory Surgery (NSAS) to determine the demographic, socioeconomic, geographic, and clinical factors associated with the likelihood of nerve block placement for ambulatory orthopedic surgery. The primary outcome of interest was the association between primary method of payment and likelihood of nerve block placement. Additionally, we examined the association between type of surgical procedures, patient demographics, and hospital characteristics with the likelihood of receiving a nerve block. Methods This cross-sectional study reviewed 6,000 orthopedic anesthetics from the 2006 NSAS dataset, which accounted for over 3.9 million orthopedic anesthetics when weighted. The primary outcome of this study addressed the likelihood of receiving a nerve block for orthopedic ambulatory surgery according to the patient’s primary method of payment. Secondary endpoints included differences in demographics, surgical procedures, side effects, complications, recovery profile, anesthesia staffing model, and total perioperative charges in those with and without nerve block. Results Overall, 14.9% of anesthetics in this sample involved a peripheral nerve block. Length of time in postoperative recovery, total perioperative time, and total charges were less for those receiving nerve blocks. Patients were more likely to receive a nerve block if their procedures were performed in metropolitan service areas (OR 1.86, 95% CI 1.19-2.91, p=0.007) or freestanding surgical facilities (OR 2.27, 95% CI 1.74-2.96, p<0.0001), and if payment for their surgery was supported by government programs (OR 2.5, 95% CI 1.01-6.21, p=0.048) or private insurance (OR 2.62, 95% CI 1.12-6.13, p=0.03) versus self-pay or charity care. Conclusion For patients

  2. Importance of Vigilant Monitoring After Continuous Nerve Block: Lessons From a Case Report

    PubMed Central

    Nair, Gopakumar Sudhakaran; Soliman, Loran Mounir; Maheshwari, Kamal; Esa, Wael Ali Sakr

    2013-01-01

    Introduction Continuous peripheral nerve block achieves good pain control. However, uncontrolled pain despite an effective block in the target areas of the nerve can be an early sign of ischemia. We report a case of iatrogenic injury to the axillary artery during shoulder surgery in a patient who had continuous supraclavicular block and demonstrate how vigilant monitoring helped the diagnosis and resulted in timely management of upper limb ischemia. Case Report A 58-year-old female underwent total revision surgery of her right shoulder under continuous supraclavicular block. Postoperatively, she complained of pain along the medial side of her forearm despite clinical evidence of nerve block. Continuous neurovascular monitoring and timely angiography confirmed axillary artery injury, and subsequent vascular repair saved the patient's limb. Conclusion Iatrogenic injuries to vessels or nerves sometimes occur during orthopedic surgical procedures. Regional anesthesia can mask and delay the onset of these symptoms. Postoperative monitoring and the ability to differentiate between the effects of local anesthetics and the body's response to ischemia are important for avoiding postoperative complications. This case report aims to improve awareness about the need for vigilant monitoring of the distal pulses after peripheral nerve blocks. PMID:23789016

  3. Skin and mucosal ischemia as a complication after inferior alveolar nerve block

    PubMed Central

    Aravena, Pedro Christian; Valeria, Camila; Nuñez, Nicolás; Perez-Rojas, Francisco; Coronado, Cesar

    2016-01-01

    The anesthetic block of the inferior alveolar nerve (IAN) is one of the most common techniques used in dental practice. The local complications are due to the failures on the anesthetic block or to anatomic variations in the tap site such as intravascular injection, skin ischemia and ocular problems. The aim of this article is to present a case and discuss the causes of itching and burning sensation, blanching, pain and face ischemia in the oral cavity during the IAN block. PMID:28182074

  4. 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

  5. A case report of complex auricular neuralgia treated with the great auricular nerve and facet blocks

    PubMed Central

    Eghtesadi, Marzieh; Leroux, Elizabeth; Vargas-Schaffer, Grisell

    2017-01-01

    Background The great auricular nerve is a cutaneous branch of the cervical plexus originating from the C2 and C3 spinal nerves. It innervates the skin over the external ear, the angle of the mandible and the parotid gland. It communicates with the ansa cervicalis. Great auricular neuralgia is rarely diagnosed in clinical practice and can be refractory. We present a new approach using ultrasound-guided nerve blocks. Case We present a case of a 41-year-old female with paroxysmal ear pain accompanied by dysautonomia, tingling in the tongue, dysphagia, dysarthria and abdominal symptoms. No significant findings were found on cervical and brain imaging. The patient responded partially to a great auricular nerve block. A combined approach using this block with facet block of C2 and C3 induced a more pronounced and prolonged benefit. Conclusion Great auricular neuralgia is not often encountered in practice and can be accompanied by symptoms originating from the ansa cervicalis network. A combined approach of nerve blocks can be considered in refractory cases. PMID:28255253

  6. 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

  7. Pain management via Ultrasound-guided Nerve Block in Emergency Department; a Case Series Study

    PubMed Central

    Nejati, Amir; Teymourian, Houman; Behrooz, Leili; mohseni, Gholamreza

    2017-01-01

    Introduction: Pain is the most common complaint of patients referring to emergency department (ED). Considering the importance of pain management in ED, this study aimed to investigate the efficacy and feasibility of ultrasound-guided nerve blocks in this setting. Methods: 46 patients who came to the ED with injured extremities were enrolled in the study and received either femoral, axillary or sciatic nerve block depending on their site of injury (1.5 mg Bupivacaine per kg of patient’s weight). Patients were asked about their level of pain before and after receiving the nerve block based on numerical rating scale. The difference between pre and post block pain severity was measured. Both patients and physicians were asked about their satisfaction with the nerve block in 5 tiered Likert scale. Results: 46 patients with the mean age of 37.5 ± 12.5 years (8-82 years) received ultrasound-guided nerve block (84.8% male). 6 Sciatic, 25 axillary, and 15 femoral nerve blocks were performed. Mean pain severity on NRS score at the time of admission was 8.1 ± 1.4, which reduced to 2.04 ± 2.06 after block. 25 (54.3%) patients were highly satisfied (Likert scale 5), 15 (32.6%) were satisfied (Likert scale 4), 3 (6.5%) were neutral and had no opinion (Likert scale 3), 1 (2.1%) was not satisfied (Likert scale 2), and 2 (4.3%) were highly unsatisfied (Likert scale 1). There was no significant difference among the satisfaction scores within the three block locations (p = 0.8). There was no significant difference in physicians’ level of satisfaction between the three block locations either (p = 0.9). 1 (2.1%) case of agitation and tachycardia and 1 (2.1%) case of vomiting were observed after the procedure. Conclusion: Ultrasound-guided nerve block of extremities is a safe and effective method that can be used for pain management in the ED. It results in high levels of satisfaction among both patients and physicians.

  8. Selectivity of voluntary finger flexion during ischemic nerve block of the hand

    PubMed Central

    Reilly, Karen T.; Schieber, Marc H.; McNulty, Penelope A.

    2009-01-01

    During ischemic nerve block of an extremity, the cortical representations of muscles proximal to the block are known to expand, increasing the overlap of different muscle representations. Such reorganization mimics that seen in actual amputees. We investigated whether such changes degrade voluntary control of muscles proximal to the block. Nine subjects produced brief, isometric flexion force selectively with each fingertip before, during, and after ischemic block at the wrist. We recorded the isometric force exerted at the distal phalanx of each digit, along with electromyographic (EMG) activity from intrinsic and extrinsic finger muscles. Despite paralysis of the intrinsic hand muscles, and associated decrements in the flexion forces exerted by the thumb, index, and little fingers, the selectivity of voluntary finger flexion forces and of EMG activity in the extrinsic finger muscles that generated these forces remained unchanged. Our observations indicate that during ischemic nerve block, reorganization does not eliminate or degrade motor representations of the temporarily deafferented and paralyzed fingers. PMID:18431564

  9. A Case of Pneumothorax after Phrenic Nerve Block with Guidance of a Nerve Stimulator

    PubMed Central

    Tüfek, Adnan; Tokgöz, Orhan; Karaman, Haktan

    2011-01-01

    Hiccups have more than 100 etiologies. The most common etiology has gastrointestinal origins, related mainly to gastric distention and gastroesophageal reflux disease. Intractable hiccups are rare but may present as a severe symptom of various diseases. Hiccups are mostly treated with non-invasive or pharmacological therapies. If these therapies fail, invasive methods should be used. Here, we present a patient on whom we performed a blockage of the phrenic nerve with the guidance of a nerve stimulator. The patient also had pneumothorax as a complication. Three hours after intervention, a tube thoracostomy was performed. One week later, the patient was cured and discharged from the hospital. In conclusion, a stimulator provides the benefit of localizing the phrenic nerve, which leads to diaphragmatic contractions. Patients with thin necks have more risk of pneumothorax during phrenic nerve location. PMID:21716608

  10. The role of peripheral nerve ECM components in the tissue engineering nerve construction.

    PubMed

    Gao, Xupeng; Wang, Yu; Chen, Jifeng; Peng, Jiang

    2013-01-01

    The extracellular matrix (ECM) is the naturally occurring substrate that provides a support structure and an attachment site for cells. It also produces a biological signal, which plays an important role in and has significant impact on cell adhesion, migration, proliferation, differentiation, and gene expression. Peripheral nerve repair is a complicated process involving Schwann cell proliferation and migration, 'bands of Büngner' formation, and newborn nerve extension. In the ECM of peripheral nerves, macromolecules are deposited among cells; these constitute the microenvironment of Schwann cell growth. Such macromolecules include collagen (I, III, IV, V), laminin, fibronectin, chondroitin sulfate proteoglycans (CSPGs), and other nerve factors. Collagen, the main component of ECM, provides structural support and guides newborn neurofilament extension. Laminin, fibronectin, CSPGs, and neurotrophic factors, are promoters or inhibitors, playing different roles in nerve repair after injury. By a chemical decellularization process, acellular nerve allografting eliminates the antigens responsible for allograft rejection and maintains most of the ECM components, which can effectively guide and enhance nerve regeneration. Thus, the composition and features of peripheral nerve ECM suggest its superiority as nerve repair material. This review focuses on the structure, function, and application in the tissue engineering nerve construction of the peripheral nerve ECM components.

  11. Hypoesthesia after IAN block anesthesia with lidocaine: management of mild to moderate nerve injury

    PubMed Central

    Moon, Sungjoo; Lee, Seung-Jong; Kim, Euiseong

    2012-01-01

    Hypoesthesia after an inferior alveolar nerve (IAN) block does not commonly occur, but some cases are reported. The causes of hypoesthesia include a needle injury or toxicity of local anesthetic agents, and the incidence itself can cause stress to both dentists and patients. This case presents a hypoesthesia on mental nerve area followed by IAN block anesthesia with 2% lidocaine. Prescription of steroids for a week was performed and periodic follow up was done. After 1 wk, the symptoms got much better and after 4 mon, hypoesthesia completely disappeared. During this healing period, only early steroid medication was prescribed. In most cases, hypoesthesia is resolved within 6 mon, but being aware of etiology and the treatment options of hypoesthesia is important. Because the hypoesthesia caused by IAN block anesthesia is a mild to moderate nerve injury, early detection of symptom and prescription of steroids could be helpful for improvement of the hypoesthesia. PMID:23430216

  12. Obturator Nerve Block in Transurethral Resection of Bladder Tumor: A Comparative Study by two Techniques

    PubMed Central

    Sharma, Deepak; Singh, V. P.; Agarwal, Nidhi; Malhotra, M. K.

    2017-01-01

    Context: Sparing of obturator nerve is a common problem encountered during transurethral resection of bladder tumor (TURBT) under spinal anesthesia. Aims: To evaluate and compare obturator nerve block (ONB) by two different techniques during TURBT. Settings and Design: This is prospective observational study. Subjects and Methods: Forty adult male patients from the American Society of Anesthesiologists Class I–IV planned to undergo TURBT under spinal anesthesia were divided into two groups of twenty each. In one group, ONB was performed with nerve locator. In other group, transvesical nerve block was performed with a cystoscope. The primary endpoints of this study were the occurrence of adductor reflex, ability to resect the tumor, and number of surgical interruptions. A number of transfusions required and bladder perforation were the secondary endpoints. Results: There was statistically significant difference between the groups for resection without adductor jerk, resection with a minimal jerk, and unresectable with high-intensity adductor jerk. Bleeding was observed in both groups and one bladder perforation was encountered. Conclusions: We conclude that ONB, when administered along with spinal anesthesia for TURBT, is extremely safe and effective method of anesthesia to overcome adductor contraction. ONB with nerve locator appears to be more effective method compared to the transvesical nerve block. PMID:28298765

  13. 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.

  14. Medial pterygoid trismus (myospasm) following inferior alveolar nerve block: case report and literature review.

    PubMed

    Wright, Edward F

    2011-01-01

    A patient developed a medial pterygoid trismus (myospasm) the day after receiving three inferior alveolar nerve blocks and a routine restoration. She had a significantly restricted mouth opening and significant medial pterygoid muscle pain when she opened beyond the restriction; however, she had no swelling, lymphadenopathy, or fever. A medial pterygoid myospasm can occur secondary to an inferior alveolar nerve block. This disorder generally is treated by the application of heat, muscle stretches, analgesic and/or muscle relaxant ingestion, and a physical therapy referral. The severity of the disorder typically dictates the extent of therapy that is needed.

  15. 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

  16. 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

  17. Vagus nerve stimulation blocks vascular permeability following burn in both local and distal sites.

    PubMed

    Ortiz-Pomales, Yan T; Krzyzaniak, Michael; Coimbra, Raul; Baird, Andrew; Eliceiri, Brian P

    2013-02-01

    Recent studies have shown that vagus nerve stimulation (VNS) can block the burn-induced systemic inflammatory response (SIRS). In this study we examined the potential for VNS to modulate vascular permeability (VP) in local sites (i.e. skin) and in secondary sites (i.e. lung) following burn. In a 30% total body surface area burn model, VP was measured using intravascular fluorescent dextran for quantification of the VP response in skin and lung. A peak in VP of the skin was observed 24h post-burn injury, that was blocked by VNS. Moreover, in the lung, VNS led to a reduction in burn-induced VP compared to sham-treated animals subjected to burn alone. The protective effects of VNS in this model were independent of the spleen, suggesting that the spleen was not a direct mediator of VNS. These studies identify a role for VNS in the regulation of VP in burns, with the translational potential of attenuating lung complications following burn.

  18. A conduction block in sciatic nerves can be detected by magnetic motor root stimulation.

    PubMed

    Matsumoto, Hideyuki; Konoma, Yuko; Fujii, Kengo; Hanajima, Ritsuko; Terao, Yasuo; Ugawa, Yoshikazu

    2013-08-15

    Useful diagnostic techniques for the acute phase of sciatic nerve palsy, an entrapment neuropathy, are not well established. The aim of this paper is to demonstrate the diagnostic utility of magnetic sacral motor root stimulation for sciatic nerve palsy. We analyzed the peripheral nerves innervating the abductor hallucis muscle using both electrical stimulations at the ankle and knee and magnetic stimulations at the neuro-foramina and conus medullaris levels in a patient with sciatic nerve palsy at the level of the piriformis muscle due to gluteal compression related to alcohol consumption. On the fourth day after onset, magnetic sacral motor root stimulation using a MATS coil (the MATS coil stimulation method) clearly revealed a conduction block between the knee and the sacral neuro-foramina. Two weeks after onset, needle electromyography supported the existence of the focal lesion. The MATS coil stimulation method clearly revealed a conduction block in the sciatic nerve and is therefore a useful diagnostic tool for the abnormal neurophysiological findings associated with sciatic nerve palsy even at the acute phase.

  19. Defining local nerve blocks for feline distal pelvic limb surgery: a cadaveric study.

    PubMed

    Enomoto, Masataka; Lascelles, B Duncan X; Gerard, Mathew P

    2017-02-01

    Objectives Anatomical and methodological detail is lacking regarding local anesthetic peripheral nerve block techniques for distal pelvic limb surgery in cats. The aim of this study was to develop, describe and test nerve block methods based on cadaveric dissections and dye injections. Methods Ten pairs of feline pelvic limbs (n = 20) were dissected and the tibial nerve (T n.), common fibular (peroneal) nerve (CF n., and its two branches, the superficial fibular [peroneal] nerve [SpF n.] and the deep fibular [peroneal] nerve [DpF n.]) and the saphenous nerve (Sa n.) were identified. Based on these dissections, a 'distal crus block' (selective blockade of the CF n., T n. and Sa n.) and a 'distal pes block' (selective blockade of the SpF n., DpF n., T n. and Sa n.) were developed for surgical procedures in two different regions of the distal pelvic limb. Techniques were tested using new methylene blue (NMB) dye injections in feline pelvic limbs (n = 12). Using a 25 G × 5/8 inch needle and 1 ml syringe, 0.1 ml/kg of NMB dye solution was injected at the site of the CF n., and 0.05 ml/kg was injected at the sites of the SpF n., DpF n., Sa n. and T n. The length and circumference (fully or partially stained) of each stained nerve were measured. Results Positive staining of nerves was observed in 12/12 limbs. The lengths stained for the CF n., DpF n., SpF n., Sa n. and T n. were 27.19 ± 7.13, 20.39 ± 5.57, 22.82 ± 7.13, 30.89 ± 6.99 and 25.16 ± 8.09 mm, respectively. The nerves were fully stained in 12, 12, 10, 11 and 11 out of 12 limbs, respectively. Conclusions and relevance These two, three-point injection methods may be an effective perioperative analgesia technique for feline distal pelvic limb procedures.

  20. Ultrasound-Guided Proximal Suprascapular Nerve Block With Radiofrequency Lesioning for Patients With Malignancy-Associated Recalcitrant Shoulder Pain.

    PubMed

    Chang, Ke-Vin; Hung, Chen-Yu; Wang, Tyng-Guey; Yang, Rong-Sen; Sun, Wei-Zen; Lin, Chih-Peng

    2015-11-01

    The classic suprascapular nerve block has limitations, such as postural requirements and lack of direct nerve visualization. This series investigated the analgesic effect of ultrasound-guided supraclavicular suprascapular nerve blocks in patients with malignancy-associated shoulder pain. Ablative radiofrequency lesioning of the suprascapular nerve in 6 patients provided substantial pain relief. The mean distance from the suprascapular nerve to the brachial plexus was 8.05 mm, and the mean angle of needle entry was 20.6°. This approach appears to be effective in relieving malignancy-associated shoulder pain and is tolerated by patients unable to sit or lie prone.

  1. 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

  2. Hip hemiarthroplasty using major lower limb nerve blocks: A preliminary report of a case series

    PubMed Central

    Taha, Ahmad Muhammad; Ghoneim, Mohammed Abd-Elfttah

    2014-01-01

    Background: Major lower limb nerve blocks are relatively safe techniques. However, their efficacy for hip hemiarthroplasty is unknown. The objective of this study was to determine the effectiveness of combined femoral, sciatic, obturator and lateral femoral cutaneous (LFC) nerve blocks in providing adequate anesthesia for hip hemiarthroplasty. Materials and Methods: A total of 20 patients with fracture neck femur; who underwent hip hemiarthroplasty, participated in this observational study. In the induction room, all patients received ultrasound-guided femoral, proximal obturator, LFC and parasacral sciatic nerve blocks in addition to local infiltration at the proximal site of the skin incision. Anesthesia was considered to be adequate only if the surgery was completed without any requirement for opioid administration. Results: All patients (100% [95% confidence interval, 86-100%]) had adequate anesthesia. Seventeen patients (85% [95% confidence interval, 63-96%] had mild discomfort during the reduction of the prosthetic femur head back into the hip socket; however, no supplementary analgesics were required. Conclusion: The combined femoral, sciatic, obturator and LFC nerve blocks in addition to local infiltration at the proximal site of skin incision could provide adequate anesthesia for hip hemiarthroplasty. Light sedation before reduction of the prosthetic femur head back into the hip socket is advisable. PMID:25191186

  3. Fixation of bilateral condylar fractures with maxillary and mandibular nerve blocks

    PubMed Central

    Parthasarathy, S.; Sripriya, R.

    2015-01-01

    Mandibulo facial injuries present special problems to the anesthesiologist in terms of the difficult airway. Hence, if regional anesthesia could be possible, it necessarily removes the major concern with airway access. We present a case of bilateral mandibular condylar fracture dislocation with the maxillary and mandibular nerve blocks on both sides. The surgery went on smoothly without any perioperative problems. PMID:26417146

  4. 2,4-Dinitrophenol blocks neurodegeneration and preserves sciatic nerve function after trauma.

    PubMed

    da Costa, Rodrigo F Madeiro; Martinez, Ana M Blanco; Ferreira, Sergio T

    2010-05-01

    Preventing the harm caused by nerve degeneration is a major challenge in neurodegenerative diseases and in various forms of trauma to the nervous system. The aim of the current work was to investigate the effects of systemic administration of 2,4-dinitrophenol (DNP), a compound with newly recognized neuroprotective properties, on sciatic-nerve degeneration following a crush injury. Sciatic-nerve injury was induced by unilateral application of an aneurysm clip. Four groups of mice were used: uninjured, injured treated with vehicle (PBS), injured treated with two intraperitoneal doses of DNP (0.06 mg DNP/kg every 24 h), and injured treated with four doses of DNP (every 12 h). Animals were sacrificed 48 h post injury and both injured and uninjured (contralateral) sciatic nerves were processed for light and electron microscopy. Morphometric, ultrastructural, and immunohistochemical analysis of injured nerves established that DNP prevented axonal degeneration, blocked cytoskeletal disintegration, and preserved the immunoreactivity of amyloid precursor protein (APP) and Neuregulin 1 (Nrg1), proteins implicated in neuronal survival and myelination. Functional tests revealed preservation of limb function following injury in DNP-treated animals. Results indicate that DNP prevents nerve degeneration and suggest that it may be a useful small-molecule adjuvant in the development of novel therapeutic approaches in nerve injury.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. Paravertebral cervical nerve block in a patient suffering from a Pancoast tumor.

    PubMed

    Peláez, Raquel; Pascual, Gabriel; Aguilar, José L; Atanassoff, Peter G

    2010-12-01

    In patients with aggressive tumors resistant to conventional pain treatment, regional anaesthesia frequently becomes an alternative therapy. Cervical paravertebral nerve block among several access options to the brachial plexus is barely ever used. We present a case with severe shoulder and upper extremity pain owing to an expanding Pancoast tumor exhibiting compression upon the brachial plexus. Continuous intrathecal morphine infusion and adjuvant treatment was not sufficient to render the patient pain-free. With the addition of paravertebral nerve blockade the patient's pain improved substantially, however without impacting his longevity.

  10. Anesthetic efficacy of lidocaine/meperidine for inferior alveolar nerve blocks in patients with irreversible pulpitis.

    PubMed

    Bigby, Jason; Reader, Al; Nusstein, John; Beck, Mike

    2007-01-01

    The purpose of this prospective, randomized, single-blind study was to compare the anesthetic efficacy of lidocaine with epinephrine to lidocaine plus meperidine with epinephrine for inferior alveolar nerve blocks (IAN) in patients with mandibular posterior teeth experiencing irreversible pulpitis. Forty-eight emergency patients diagnosed with irreversible pulpitis of a mandibular posterior tooth randomly received, in a single-blind manner, 36 mg of lidocaine with 18 mug epinephrine or 36 mg of lidocaine with 18 mug of epinephrine plus 36 mg meperidine with 18 mug epinephrine, using a conventional inferior alveolar nerve block. Endodontic access was begun 15 minutes after solution deposition, and all patients were required to have profound lip numbness. Success was defined as no or mild pain (visual analog scale recordings) upon endodontic access or initial instrumentation. The success rate for the inferior alveolar nerve block using the lidocaine solution was 26%, and for the lidocaine/meperidine solution, the success rate was 12%. There was no significant difference (p = 0.28) between the two solutions. In conclusion, for mandibular posterior teeth with irreversible pulpitis, the addition of 36 mg of meperidine to a lidocaine solution administered in a conventional IAN block did not improve the success rate over a standard lidocaine solution.

  11. Comparison of peripheral nerve stimulator versus ultrasonography guided axillary block using multiple injection technique

    PubMed Central

    Kumar, Alok; Sharma, DK; Sibi, Maj. E; Datta, Barun; Gogoi, Biraj

    2014-01-01

    Background: The established methods of nerve location were based on either proper motor response on nerve stimulation (NS) or ultrasound guidance. In this prospective, randomised, observer-blinded study, we compared ultrasound guidance with NS for axillary brachial plexus block using 0.5% bupivacaine with the multiple injection techniques. Methods: A total of 120 patients receiving axillary brachial plexus block with 0.5% bupivacaine, using a multiple injection technique, were randomly allocated to receive either NS (group NS, n = 60), or ultrasound guidance (group US, n = 60) for nerve location. A blinded observer recorded the onset of sensory and motor blocks, skin punctures, needle redirections, procedure-related pain and patient satisfaction. Results: The median (range) number of skin punctures were 2 (2–4) in group US and 3 (2–5) in group NS (P < 0.001). No differences were observed in the onset of sensory block in group NS (6.17 ± 1.22 min) and in group US (6.33 ± 0.48 min) (P = 0.16), and in onset of motor block (23.33 ± 1.26 min) in group US and (23.17 ± 1.79 min) in group NS; P > =0.27). Insufficient block was observed in three patient (5%) of group US and four patients (6.67%) of group NS (P > =0.35). Patient acceptance was similarly good in the two groups. Conclusion: Multiple injection axillary blocks with ultrasound guidance provided similar success rates and comparable incidence of complications as compared with NS guidance with 20 ml 0.5% bupivacaine. PMID:25624532

  12. A comparative evaluation of anesthetic efficacy of articaine 4% and lidocaine 2% with anterior middle superior alveolar nerve block and infraorbital nerve block: An in vivo study

    PubMed Central

    Saraf, Suma Prahlad; Saraf, Prahlad Annappa; Kamatagi, Laxmikant; Hugar, Santosh; Tamgond, Shridevi; Patil, Jayakumar

    2016-01-01

    Background: The ideal maxillary injection should produce a rapid onset of profound pulpal anesthesia for multiple teeth from a single needle penetration. The main objective is to compare the efficacy of articaine 4% and lidocaine 2% and to compare anterior middle superior alveolar nerve block (AMSANB) and infraorbital nerve block (IONB) for anesthesia of maxillary teeth. Materials and Methods: Forty patients undergoing root canal treatment of maxillary anteriors and premolars were included and randomly divided into four groups of ten each. Group I: patients receiving AMSANB with articaine, Group II: Patients receiving IONB with articaine, Group III: Patients receiving AMSANB with lidocaine, Group IV: Patients receiving IONB with lidocaine. The scores of onset of anesthesia and pain perception were statistically analyzed. Results: Onset of action was fastest for articaine with AMSANB and slowest for lidocaine with IONB by Tukey's test. A significant change was observed in the electrical pulp test readings at onset and at 30 min by paired t-test. All patients experienced mild pain during the procedure recorded by visual analog scale. Conclusion: Articaine 4% proved to be more efficacious than lidocaine 2%, and AMSANB was more advantageous than IONB in securing anesthesia of maxillary anteriors and premolars. PMID:27994313

  13. Action potential propagation and propagation block by GABA in rat posterior pituitary nerve terminals.

    PubMed Central

    Jackson, M B; Zhang, S J

    1995-01-01

    1. A theoretical model was developed to investigate action potential propagation in posterior pituitary nerve terminals. This model was then used to evaluate the efficacy of depolarizing and shunting GABA responses on action potential propagation. 2. Experimental data obtained from the posterior pituitary with patch clamp techniques were used to derive empirical expressions for the voltage and time dependence of the nerve terminal Na+ and K+ channels. The essential structure employed here was based on anatomical and cable data from the posterior pituitary, and consisted of a long cylindrical axon (diameter, 0.5 mm) with a large spherical swelling (diameter, 4-21 mm) in the middle. 3. In the absence of an inhibitory conductance, simulated action potentials propagated with high fidelity through the nerve terminal. Swellings could block propagation, but only when sizes exceeded those observed in the posterior pituitary. Adding axonal branches reduced the critical size only slightly. These results suggested that action potentials invade the entire posterior pituitary nerve terminal in the absence of inhibition or depression. 4. The addition of inhibitory conductance to a swelling caused simulated action potentials to fail at the swelling. Depolarizing inhibitory conductances were 1.6 times more effective than shunting inhibitory conductances in blocking propagation. 5. Inhibitory conductances within the range of experimentally observed magnitudes and localized to swellings in the observed range of sizes were too weak to block simulated action potentials. However, twofold enhancement of GABA responses by neurosteroid resulted in currents strong enough to block propagation in realistic swelling sizes. 6. GABA could block simulated propagation without neurosteroid enhancement provided that GABA was present throughout a region in the order of a few hundred micrometres. For this widespread inhibition depolarizing conductance was 2.2 times more effective than shunting

  14. Temporary Nerve Block at Selected Digits Revealed Hand Motor Deficits in Grasping Tasks

    PubMed Central

    Carteron, Aude; McPartlan, Kerry; Gioeli, Christina; Reid, Emily; Turturro, Matt; Hahn, Barry; Benson, Cynthia; Zhang, Wei

    2016-01-01

    Peripheral sensory feedback plays a crucial role in ensuring correct motor execution throughout hand grasp control. Previous studies utilized local anesthesia to deprive somatosensory feedback in the digits or hand, observations included sensorimotor deficits at both corticospinal and peripheral levels. However, the questions of how the disturbed and intact sensory input integrate and interact with each other to assist the motor program execution, and whether the motor coordination based on motor output variability between affected and non-affected elements (e.g., digits) becomes interfered by the local sensory deficiency, have not been answered. The current study aims to investigate the effect of peripheral deafferentation through digital nerve blocks at selective digits on motor performance and motor coordination in grasp control. Our results suggested that the absence of somatosensory information induced motor deficits in hand grasp control, as evidenced by reduced maximal force production ability in both local and non-local digits, impairment of force and moment control during object lift and hold, and attenuated motor synergies in stabilizing task performance variables, namely the tangential force and moment of force. These findings implied that individual sensory input is shared across all the digits and the disturbed signal from local sensory channel(s) has a more comprehensive impact on the process of the motor output execution in the sensorimotor integration process. Additionally, a feedback control mechanism with a sensation-based component resides in the formation process for the motor covariation structure. PMID:27932964

  15. Facial palsy after inferior alveolar nerve block: case report and review of the literature.

    PubMed

    Chevalier, V; Arbab-Chirani, R; Tea, S H; Roux, M

    2010-11-01

    Bell's palsy is an idiopathic and acute, peripheral nerve palsy resulting in inability to control facial muscles on the affected side because of the involvement of the facial nerve. This study describes a case of Bell's palsy that developed after dental anaesthesia. A 34-year-old pregnant woman at 35 weeks of amenorrhea, with no history of systemic disease, was referred by her dentist for treatment of a mandibular left molar in pulpitis. An inferior alveolar nerve block was made prior to the access cavity preparation. 2h later, the patient felt the onset of a complete paralysis of the left-sided facial muscles. The medical history, the physical examination and the complementary exams led neurologists to the diagnosis of Bell's palsy. The treatment and results of the 1-year follow-up are presented and discussed. Bell's palsy is a rare complication of maxillofacial surgery or dental procedures, the mechanisms of which remain uncertain.

  16. Post-stimulation block of frog sciatic nerve by high-frequency (kHz) biphasic stimulation.

    PubMed

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

    2017-04-01

    This study determined if high-frequency biphasic stimulation can induce nerve conduction block that persists after the stimulation is terminated, i.e., post-stimulation block. The frog sciatic nerve-muscle preparation was used in the study. Muscle contraction force induced by low-frequency (0.5 Hz) nerve stimulation was recorded to indicate the occurrence and recovery of nerve block induced by the high-frequency (5 or 10 kHz) biphasic stimulation. Nerve block was observed during high-frequency stimulation and after termination of the stimulation. The recovery from post-stimulation block occurred in two distinct phases. During the first phase, the complete block induced during high-frequency stimulation was maintained. The average maximal duration for the first phase was 107 ± 50 s. During the second phase, the block gradually or abruptly reversed. The duration of both first and second phases was dependent on stimulation intensity and duration but not frequency. Stimulation of higher intensity (1.4-2 times block threshold) and longer duration (5 min) produced the longest period (249 ± 58 s) for a complete recovery. Post-stimulation block can be induced by high-frequency biphasic stimulation, which is important for future investigations of the blocking mechanisms and for optimizing the stimulation parameters or protocols in clinical applications.

  17. 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.

  18. 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.

  19. Ultrasound-Guided Obturator Nerve Block: A Focused Review on Anatomy and Updated Techniques

    PubMed Central

    Nakamoto, Tatsuo; Kamibayashi, Takahiko

    2017-01-01

    This review outlines the anatomy of the obturator nerve and the indications for obturator nerve block (ONB). Ultrasound-guided ONB techniques and unresolved issues regarding these procedures are also discussed. An ONB is performed to prevent thigh adductor jerk during transurethral resection of bladder tumor, provide analgesia for knee surgery, treat hip pain, and improve persistent hip adductor spasticity. Various ultrasound-guided ONB techniques can be used and can be classified according to whether the approach is distal or proximal. In the distal approach, a transducer is placed at the inguinal crease; the anterior and posterior branches of the nerve are then blocked by two injections of local anesthetic directed toward the interfascial planes where each branch lies. The proximal approach comprises a single injection of local anesthetic into the interfascial plane between the pectineus and obturator externus muscles. Several proximal approaches involving different patient and transducer positions are reported. The proximal approach may be superior for reducing the dose of local anesthetic and providing successful blockade of the obturator nerve, including the hip articular branch, when compared with the distal approach. This hypothesis and any differences between the proximal ONB techniques need to be explored in future studies. PMID:28280738

  20. [Ultrasound-guided cutaneous intercostal branches nerves block: A good analgesic alternative for gallbladder open surgery].

    PubMed

    Fernández Martín, M T; López Álvarez, S; Mozo Herrera, G; Platero Burgos, J J

    2015-12-01

    Laparoscopic cholecystectomy has become the standard treatment for gallbladder diseases. However, there are still some patients for whom conversion to open surgery is required. This surgery can produce significant post-operative pain. Opioids drugs have traditionally been used to treat this pain, but side effects have led to seeking alternatives (plexus, nerve or fascia blocks or wound). The cases are presented of 4 patients subjected to ultrasound-guided intercostal branches blocks in the mid-axillary line from T6 to T12 with levobupivacaine as an analgesic alternative in open surgery of gallbladder, with satisfactory results.

  1. Management of exaggerated gagging in prosthodontic patients using glossopharyngeal nerve block

    PubMed Central

    Murthy, Varsha; V, Yuvraj; Nair, Preeti P; Thomas, Shaji; Krishna, Akash; Cyriac, Sumeeth

    2011-01-01

    When gag reflex becomes abnormally active, it poses difficulty for the prosthodontists, as it hinders the process of fixed partial denture construction beginning with tooth preparation till impression making. In this case-report, the authors used a nerve block technique which is popular among anaesthetist and otolaryngologist, but is being applied in the field of prosthodontics for the first time, to tide over the difficulty. PMID:22679052

  2. 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

  3. Effect of a new local anesthetic buffering device on pain reduction during nerve block injections.

    PubMed

    Comerci, Andrew W; Maller, Steven C; Townsend, Richard D; Teepe, John D; Vandewalle, Kraig S

    2015-01-01

    The purpose of this double-blind, split-mouth, randomized human clinical study was to evaluate the effectiveness of a new sodium bicarbonate local anesthetic buffering device (Onset) in reducing pain associated with dental injections. Twenty patients were given bilateral inferior alveolar (IA) and long buccal (LB) nerve block injections and asked to quantify the pain experienced during injection on a visual analog scale (0, no pain; 10, worst possible pain). One side of the mouth received standard-of-care injections of 2% lidocaine with 1:100,000 epinephrine. On the opposite side, after the buffering device was used to mix the components within the anesthetic carpule, patients received injections of 2% lidocaine with 1:100,000 epinephrine buffered 9:1 with 8.4% sodium bicarbonate. The mean pain scores were 2.7 (SD, 1.3) for buffered and 2.7 (SD, 1.9) for unbuffered IA injections. The mean pain scores were 2.0 (SD, 1.4) for buffered and 2.7 (SD, 1.8) for unbuffered LB injections. The data were analyzed with a paired t test (α = 0.05), and no statistically significant difference was found between groups for IA (P = 0.94) or LB (P = 0.17) nerve block injections. In this study of patients receiving common dental nerve block injections, local anesthetic buffering technology did not significantly lessen pain compared to that experienced during a standard unbuffered injection.

  4. 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

  5. Glossopharyngeal Nerve Block versus Lidocaine Spray to Improve Tolerance in Upper Gastrointestinal Endoscopy

    PubMed Central

    Ortega Ramírez, Moisés; Linares Segovia, Benigno; García Cuevas, Marco Antonio; Sánchez Romero, Jorge Luis; Botello Buenrostro, Illich; Amador Licona, Norma; Guízar Mendoza, Juan Manuel; Guerrero Romero, Jesús Francisco; Vázquez Zárate, Víctor Manuel

    2013-01-01

    Aim of the Study. To compare the effect of glossopharyngeal nerve block with topical anesthesia on the tolerance of patients to upper gastrointestinal endoscopy. Methods. We performed a clinical trial in one hundred patients undergoing upper gastrointestinal endoscopy. Subjects were randomly assigned to one of the following two groups: (1) treatment with bilateral glossopharyngeal nerve block (GFNB) and intravenous midazolam or (2) treatment with topical anesthetic (TASS) and intravenous midazolam. We evaluated sedation, tolerance to the procedure, hemodynamic stability, and adverse symptoms. Results. We studied 46 men and 54 women, from 17 to 78 years of age. The procedure was reported without discomfort in 48 patients (88%) in the GFNB group and 32 (64%) in the TAAS group; 6 patients (12%) in GFNB group and 18 (36%) in TAAS group reported the procedure as little discomfort (χ2 = 3.95, P = 0.04). There was no difference in frequency of nausea (4% in both groups) and retching, 4% versus 8% for GFNB and TASS group, respectively (P = 0.55). Conclusions. The use of glossopharyngeal nerve block provides greater comfort and tolerance to the patient undergoing upper gastrointestinal endoscopy. It also reduces the need for sedation. PMID:23533386

  6. Glossopharyngeal Nerve Block versus Lidocaine Spray to Improve Tolerance in Upper Gastrointestinal Endoscopy.

    PubMed

    Ortega Ramírez, Moisés; Linares Segovia, Benigno; García Cuevas, Marco Antonio; Sánchez Romero, Jorge Luis; Botello Buenrostro, Illich; Amador Licona, Norma; Guízar Mendoza, Juan Manuel; Guerrero Romero, Jesús Francisco; Vázquez Zárate, Víctor Manuel

    2013-01-01

    Aim of the Study. To compare the effect of glossopharyngeal nerve block with topical anesthesia on the tolerance of patients to upper gastrointestinal endoscopy. Methods. We performed a clinical trial in one hundred patients undergoing upper gastrointestinal endoscopy. Subjects were randomly assigned to one of the following two groups: (1) treatment with bilateral glossopharyngeal nerve block (GFNB) and intravenous midazolam or (2) treatment with topical anesthetic (TASS) and intravenous midazolam. We evaluated sedation, tolerance to the procedure, hemodynamic stability, and adverse symptoms. Results. We studied 46 men and 54 women, from 17 to 78 years of age. The procedure was reported without discomfort in 48 patients (88%) in the GFNB group and 32 (64%) in the TAAS group; 6 patients (12%) in GFNB group and 18 (36%) in TAAS group reported the procedure as little discomfort (χ (2) = 3.95, P = 0.04). There was no difference in frequency of nausea (4% in both groups) and retching, 4% versus 8% for GFNB and TASS group, respectively (P = 0.55). Conclusions. The use of glossopharyngeal nerve block provides greater comfort and tolerance to the patient undergoing upper gastrointestinal endoscopy. It also reduces the need for sedation.

  7. Long-term neurological complications associated with surgery and peripheral nerve blockade: outcomes after 1065 consecutive blocks.

    PubMed

    Watts, S A; Sharma, D J

    2007-02-01

    Peripheral nerve blockade is gaining popularity as an analgesic option for both upper or lower limb surgery. Published evidence supports the improved efficacy of regional techniques when compared to conventional opioid analgesia. The incidence of neurological deficit after surgery associated with peripheral nerve block is unclear. This paper reports on neurological outcomes occurring after 1065 consecutive peripheral nerve blocks over a one-year period from a single institution. All patients receiving peripheral nerve blocks for surgery were prospectively followed for up to 12 months to determine the incidence and probable cause of any persistent neurological deficit. Formal independent neurological review and testing was undertaken as indicated. Thirteen patients reported symptoms that warranted further investigation. A variety of probable causes were identified, with peripheral nerve block being implicated in two cases (one resolved at nine months and one remaining persistent). Overall incidence of block-related neuropathy was 0.22%. Persistent postoperative neuropathy is a rare but serious complication of surgery associated with peripheral nerve block. Formal follow-up of all such blocks is recommended to assess causality and allow for early intervention.

  8. 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.

  9. Nerve Blocks

    MedlinePlus

    ... mail: Area code: Phone no: Thank you! 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 ...

  10. 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

  11. Percutaneous sciatic nerve block with tramadol induces analgesia and motor blockade in two animal pain models

    PubMed Central

    Sousa, A.M.; Ashmawi, H.A.; Costa, L.S.; Posso, I.P.; Slullitel, A.

    2011-01-01

    Local anesthetic efficacy of tramadol has been reported following intradermal application. Our aim was to investigate the effect of perineural tramadol as the sole analgesic in two pain models. Male Wistar rats (280-380 g; N = 5/group) were used in these experiments. A neurostimulation-guided sciatic nerve block was performed and 2% lidocaine or tramadol (1.25 and 5 mg) was perineurally injected in two different animal pain models. In the flinching behavior test, the number of flinches was evaluated and in the plantar incision model, mechanical and heat thresholds were measured. Motor effects of lidocaine and tramadol were quantified and a motor block score elaborated. Tramadol, 1.25 mg, completely blocked the first and reduced the second phase of the flinching behavior test. In the plantar incision model, tramadol (1.25 mg) increased both paw withdrawal latency in response to radiant heat (8.3 ± 1.1, 12.7 ± 1.8, 8.4 ± 0.8, and 11.1 ± 3.3 s) and mechanical threshold in response to von Frey filaments (459 ± 82.8, 447.5 ± 91.7, 320.1 ± 120, 126.43 ± 92.8 mN) at 5, 15, 30, and 60 min, respectively. Sham block or contralateral sciatic nerve block did not differ from perineural saline injection throughout the study in either model. The effect of tramadol was not antagonized by intraperitoneal naloxone. High dose tramadol (5 mg) blocked motor function as well as 2% lidocaine. In conclusion, tramadol blocks nociception and motor function in vivo similar to local anesthetics. PMID:22183244

  12. Excitation block in a nerve fibre model owing to potassium-dependent changes in myelin resistance

    PubMed Central

    Brazhe, A. R.; Maksimov, G. V.; Mosekilde, E.; Sosnovtseva, O. V.

    2011-01-01

    The myelinated nerve fibre is formed by an axon and Schwann cells or oligodendrocytes that sheath the axon by winding around it in tight myelin layers. Repetitive stimulation of a fibre is known to result in accumulation of extracellular potassium ions, especially between the axon and the myelin. Uptake of potassium leads to Schwann cell swelling and myelin restructuring that impacts the electrical properties of the myelin. In order to further understand the dynamic interaction that takes place between the myelin and the axon, we have modelled submyelin potassium accumulation and related changes in myelin resistance during prolonged high-frequency stimulation. We predict that potassium-mediated decrease in myelin resistance leads to a functional excitation block with various patterns of altered spike trains. The patterns are found to depend on stimulation frequency and amplitude and to range from no block (less than 100 Hz) to a complete block (greater than 500 Hz). The transitional patterns include intermittent periodic block with interleaved spiking and non-spiking intervals of different relative duration as well as an unstable regime with chaotic switching between the spiking and non-spiking states. Intermittent conduction blocks are accompanied by oscillations of extracellular potassium. The mechanism of conductance block based on myelin restructuring complements the already known and modelled block via hyperpolarization mediated by the axonal sodium pump and potassium depolarization. PMID:22419976

  13. 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

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. Role of Intraoperative Nerve Monitoring During Parathyroidectomy to Prevent Recurrent Laryngeal Nerve Injury

    PubMed Central

    Assad, Salman; Assad, Shuja

    2016-01-01

    Injury to the recurrent laryngeal nerve (RLN) is a well known, though less frequent, complication of parathyroid surgery. In recent years, the use of intraoperative nerve monitoring (IONM) has gained popularity amongst surgeons when operating on thyroid gland; however, its utilization in parathyroid surgery is not established. This trend continues to rise, despite multiple studies documenting no statistically significant difference that IONM decreases the incidence of RLN injury. Most surgeons use this technology as an adjunct to visualization alone for identification of RLN. The purpose of this review is to discuss the possible role of IONM in parathyroid surgery with regards to the accuracy, efficacy, and recent trends in the utilization of this technology. There is insufficient evidence that IONM reduces the risk of RLN injury in parathyroidectomy. Although IONM may decrease the likelihood of nerve injury by helping to identify and map the RLN during thyroidectomy, we did not find studies exclusive to parathyroid surgery to see if its use can be supported for parathyroidectomy. Despite this lack of evidence, we believe that IONM is a promising adjunct to visualization alone in detecting nerve structures during neck dissection, but more clinical trials are warranted to establish its role in preventing nerve injury in parathyroid surgery. PMID:28003944

  1. 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.

  2. 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

  3. 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

    2015-12-02

    Activation of taste buds triggers the release of several neurotransmitters, including ATP and serotonin (5-hydroxytryptamine; 5-HT). Type III taste cells release 5-HT directly in response to acidic (sour) stimuli and indirectly in response to bitter and sweet tasting stimuli. Although ATP is necessary for activation of nerve fibers for all taste stimuli, the role of 5-HT is unclear. We investigated whether gustatory afferents express functional 5-HT3 receptors and, if so, whether these receptors play a role in transmission of taste information from taste buds to nerves. In mice expressing GFP under the control of the 5-HT(3A) promoter, a subset of cells in the geniculate ganglion and nerve fibers in taste buds are GFP-positive. RT-PCR and in situ hybridization confirmed the presence of 5-HT(3A) mRNA in the geniculate ganglion. Functional studies show that only those geniculate ganglion cells expressing 5-HT3A-driven GFP respond to 10 μM 5-HT and this response is blocked by 1 μM ondansetron, a 5-HT3 antagonist, and mimicked by application of 10 μM m-chlorophenylbiguanide, a 5-HT3 agonist. Pharmacological blockade of 5-HT3 receptors in vivo or genetic deletion of the 5-HT3 receptors reduces taste nerve responses to acids and other taste stimuli compared with controls, but only when urethane was used as the anesthetic. We find that anesthetic levels of pentobarbital reduce taste nerve responses apparently by blocking the 5-HT3 receptors. Our results suggest that 5-HT released from type III cells activates gustatory nerve fibers via 5-HT3 receptors, accounting for a significant proportion of the neural taste response.

  4. Alternating block polyurethanes based on PCL and PEG as potential nerve regeneration materials.

    PubMed

    Li, Guangyao; Li, Dandan; Niu, Yuqing; He, Tao; Chen, Kevin C; Xu, Kaitian

    2014-03-01

    Polyurethanes with regular and controlled block arrangement, i.e., alternating block polyurethanes (abbreviated as PUCL-alt-PEG) based on poly(ε-caprolactone) (PCL-diol) and poly(ethylene glycol) (PEG) was prepared via selectively coupling reaction between PCL-diol and diisocyanate end-capped PEG. Chemical structure, molecular weight, distribution, and thermal properties were systematically characterized by FTIR, (1)H NMR, GPC, DSC, and TGA. Hydrophilicity was studied by static contact angle of H2O and CH2I2. Film surface was observed by scanning electron microscope (SEM) and atomic force microscopy, and mechanical properties were assessed by universal test machine. Results show that alternating block polyurethanes give higher crystal degree, higher mechanical properties, and more hydrophilic and rougher (deep ravine) surface than their random counterpart, due to regular and controlled structure. Platelet adhesion illustrated that PUCL-alt-PEG has better hemocompatibility and the hemacompatibility was affected significantly by PEG content. Excellent hemocompatibility was obtained with high PEG content. CCK-8 assay and SEM observation revealed much better cell compatibility of fibroblast L929 and rat glial cells on the alternating block polyurethanes than that on random counterpart. Alternating block polyurethane PUC20-a-E4 with optimized composition, mechanical, surface properties, hemacompatibility, and highest cell growth and proliferation was achieved for potential use in nerve regeneration.

  5. 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

  6. Development and validation of an equine nerve block simulator to supplement practical skills training in undergraduate veterinary students.

    PubMed

    Gunning, P; Smith, A; Fox, V; Bolt, D M; Lowe, J; Sinclair, C; Witte, T H; Weller, R

    2013-04-27

    Lameness is the most common presenting complaint in equine practice. Performing diagnostic nerve blocks is an integral part of any lameness work-up, and is therefore an essential skill for equine practitioners. However, the opportunities for veterinary students to practice this skill are limited. The aim of this study was to design and validate an equine nerve block simulator. It was hypothesised that the simulator would improve students' ability and enhance their confidence in performing nerve blocks. A simulator was built using an equine forelimb skeleton and building foam. Wire wool targets were placed under the foam in the positions corresponding to the anatomical location of the most palmar digital, abaxial and low four-point nerve blocks and attached to an electrical circuit. The circuit became complete when the operator placed a needle in the correct position and immediate audible feedback with a buzzer was provided. To validate the simulator, it was compared with two established teaching methods: cadaver training and theoretical training with a hand-out. Cadaver-trained students achieved the best results (73 per cent correct blocks), compared with simulator-trained students (71 per cent correct blocks), and a hand-out trained group (58 per cent correct blocks). Feedback obtained with a questionnaire showed that students enjoyed simulator training more, and that they felt more confident in performing diagnostic nerve blocks than the other two groups. The equine nerve block simulator provides a safe, cost-effective method to supplement the teaching of diagnostic analgesia to undergraduate veterinary students.

  7. Effect of Arm Positioning on Entrapment of Infraclavicular Nerve Block Catheter

    PubMed Central

    Reddy, Rahul; Kendall, Mark C.; Nader, Antoun; Weeks, Jessica J.

    2017-01-01

    Continuous brachial plexus nerve block catheters are commonly inserted for postoperative analgesia after upper extremity surgery. Modifications of the insertion technique have been described to improve the safety of placing an infraclavicular brachial plexus catheter. Rarely, these catheters may become damaged or entrapped, complicating their removal. We describe a case of infraclavicular brachial plexus catheter entrapment related to differences in arm positioning during catheter placement and removal. Written authorization to obtain, use, and disclose information and images was obtained from the patient. PMID:28348896

  8. Adductor canal block versus femoral nerve block for total knee arthroplasty: a meta-analysis of randomized controlled trials

    PubMed Central

    Wang, Duan; Yang, Yang; Li, Qi; Tang, Shen-Li; Zeng, Wei-Nan; Xu, Jin; Xie, Tian-Hang; Pei, Fu-Xing; Yang, Liu; Li, Ling-Li; Zhou, Zong-Ke

    2017-01-01

    Femoral nerve blocks (FNB) can provide effective pain relief but result in quadriceps weakness with increased risk of falls following total knee arthroplasty (TKA). Adductor canal block (ACB) is a relatively new alternative providing pure sensory blockade with minimal effect on quadriceps strength. The meta-analysis was designed to evaluate whether ACB exhibited better outcomes with respect to quadriceps strength, pain control, ambulation ability, and complications. PubMed, Embase, Web of Science, Wan Fang, China National Knowledge Internet (CNKI) and the Cochrane Database were searched for RCTs comparing ACB with FNB after TKAs. Of 309 citations identified by our search strategy, 12 RCTs met the inclusion criteria. Compared to FNB, quadriceps maximum voluntary isometric contraction (MVIC) was significantly higher for ACB, which was consistent with the results regarding quadriceps strength assessed with manual muscle strength scale. Moreover, ACB had significantly higher risk of falling versus FNB. At any follow-up time, ACB was not inferior to FNB regarding pain control or opioid consumption, and showed better range of motion in comparison with FNB. ACB is superior to the FNB regarding sparing of quadriceps strength and faster knee function recovery. It provides pain relief and opioid consumption comparable to FNB and is associated with decreased risk of falls. PMID:28079176

  9. 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.

  10. Continuous Femoral Nerve Blocks: Varying Local Anesthetic Delivery Method (Bolus versus Basal) to Minimize Quadriceps Motor Block while Maintaining Sensory Block

    PubMed Central

    Charous, Matthew T.; Madison, Sarah J.; Suresh, J.; Sandhu, NavParkash S.; Loland, Vanessa J.; Mariano, Edward R.; Donohue, Michael C.; Dutton, Pascual H.; Ferguson, Eliza J.; Ilfeld, Brian M.

    2011-01-01

    Background Whether the method of local anesthetic administration for continuous femoral nerve blocks —basal infusion versus repeated hourly bolus doses —influences block effects remains unknown. Methods Bilateral femoral perineural catheters were inserted in volunteers (n = 11). Ropivacaine 0.1% was administered through both catheters concurrently: a 6-h continuous 5 ml/h basal infusion on one side and 6 hourly bolus doses on the contralateral side. The primary endpoint was the maximum voluntary isometric contraction (MVIC) of the quadriceps femoris muscle at Hour 6. Secondary end points included quadriceps MVIC at other time points, hip adductor MVIC, and cutaneous sensation 2 cm medial to the distal quadriceps tendon in the 22 h following local anesthetic administration initiation. Results Quadriceps MVIC for limbs receiving 0.1% ropivacaine as a basal infusion declined by a mean (SD) of 84% (19) compared with 83% (24) for limbs receiving 0.1% ropivacaine as repeated bolus doses between baseline and Hour 6 (paired t test P = 0.91). Intrasubject comparisons (left vs. right) reflected a lack of difference as well: the mean basal-bolus difference in quadriceps MVIC at Hour 6 was −1.1% (95% CI −22.0 to 19.8%). The similarity did not reach our a priori threshold for concluding equivalence, which was the 95% CI falling within ± 20%. There were similar minimal differences in the secondary endpoints during local anesthetic administration. Conclusions This study did not find evidence to support the hypothesis that varying the method of local anesthetic administration —basal infusion versus repeated bolus doses —influences continuous femoral nerve block effects to a clinically significant degree. PMID:21394001

  11. THE POTENTIAL ROLES FOR ADIPOSE TISSUE IN PERIPHERAL NERVE REGENERATION

    PubMed Central

    Walocko, Frances M.; Khouri, Roger K.; Urbanchek, Melanie G.; Levi, Benjamin; Cederna, Paul S.

    2016-01-01

    Introduction This review summarizes current understanding about the role of adipose-derived tissues in peripheral nerve regeneration and discusses potential advances that would translate this approach into the clinic. Methods We searched PubMed for in vivo, experimental studies on the regenerative effects of adipose-derived tissues on peripheral nerve injuries. We summarized the methods and results for the 42 experiments. Results Adipose-derived tissues enhanced peripheral nerve regeneration in 86% of the experiments. Ninety-five percent evaluated purified, cultured, or differentiated adipose tissue. These approaches have regulatory and scaling burdens, restricting clinical usage. Only one experiment tested the ability of adipose tissue to enhance nerve regeneration in conjunction with nerve autografts, the clinical gold standard. Conclusion Scientific studies illustrate that adipose-derived tissues enhance regeneration of peripheral nerves. Before this approach achieves clinical acceptance, fat processing must become automated and regulatory approval achieved. Animal studies using whole fat grafts are greatly needed for clinical translation. PMID:26773850

  12. 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

  13. 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.

  14. 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

  15. Submucous tramadol increases the anesthetic efficacy of mepivacaine with epinephrine in inferior alveolar nerve block.

    PubMed

    Isiordia-Espinoza, Mario Alberto; Orozco-Solis, Mariana; Tobías-Azúa, Francisco Javier; Méndez-Gutiérrez, Elsa Patricia

    2012-03-01

    The purpose of this study was to evaluate the effect of submucous tramadol as adjuvant of mepivacaine with epinephrine in inferior alveolar nerve block. A double-blind, randomized, placebo-controlled, crossover clinical trial was conducted. Twenty healthy young volunteers were randomized into two treatment sequences using a series of random numbers. Sequence 1: Group A, 2% mepivacaine with 1:100,000 epinephrine plus submucous tramadol 50mg (1mL of saline) and one week later Group B, 2% mepivacaine with 1:100,000 epinephrine plus submucous placebo (1mL of saline). Sequence 2: Group B and one week later Group A. All treatments were administered 1min after that patient informed anesthesia of lower lip. We evaluated the duration of anesthesia of lower lip, anesthetic efficacy, and local and systemic adverse events. Anesthetic efficacy was better in group receiving submucous tramadol during the first 2h compared with group receiving submucous placebo (P<0.05). Submucous tramadol increased the anesthetic efficacy of mepivacaine with epinephrine of soft tissue in inferior alveolar nerve block.

  16. The addition of clonidine to bupivacaine in combined femoral-sciatic nerve block for anterior cruciate ligament reconstruction.

    PubMed

    Couture, Darren J; Cuniff, Heather M; Maye, John P; Pellegrini, Joseph

    2004-08-01

    Clonidine has been shown to prolong sensory analgesia when given as an adjunct to peripheral nerve blocks but has not been evaluated when given in conjunction with a femoral-sciatic nerve block. The purpose of this investigation was to determine whether the addition of clonidine to a femoral-sciatic nerve block would prolong the duration of sensory analgesia in groups of patients undergoing anterior cruciate ligament (ACL) reconstruction. This prospective, randomized, double-blind investigation was performed on 64 subjects undergoing ACL reconstruction. Patients were assigned randomly to receive a femoral-sciatic nerve block using 30 mL of 0.5% bupivacaine with 1:200,000 epinephrine (control group) or 30 mL of 0.5% bupivacaine with 1:200,000 epinephrine and 1 microg/kg of clonidine (experimental group). Variables measured included demographics, timed pain intensity measurements, postoperative analgesic consumption, duration of analgesia, and patient satisfaction. No significant differences were noted between groups for pain intensity scores, duration of sensory analgesia, postoperative analgesic requirements, or overall patient satisfaction. Both groups reported minimal amounts of postoperative pain and high analgesic satisfaction scores. Based on our results, we do not recommend the addition of clonidine to a femoral-sciatic nerve block when given to facilitate postoperative analgesia in patients undergoing ACL reconstruction.

  17. Continuous Femoral Nerve Blocks: Decreasing Local Anesthetic Concentration to Minimize Quadriceps Femoris Weakness

    PubMed Central

    Bauer, Maria; Wang, Lu; Onibonoje, Olusegun K.; Parrett, Chad; Sessler, Daniel I.; Mounir-Soliman, Loran; Zaky, Sherif; Krebs, Viktor; Buller, Leonard T.; Donohue, Michael C.; Stevens-Lapsley, Jennifer E.; Ilfeld, Brian M.

    2012-01-01

    Background Whether decreasing the local anesthetic concentration during a continuous femoral nerve block results in less quadriceps weakness remains unknown. Methods Preoperatively, bilateral femoral perineural catheters were inserted in patients undergoing bilateral knee arthroplasty (n = 36) at a single clinical center. Postoperatively, right-sided catheters were randomly assigned to receive perineural ropivacaine of either 0.1% (basal 12 mL/h; bolus 4 mL) or 0.4% (basal 3 mL/h; bolus 1 mL), with the left catheter receiving the alternative concentration/rate in an observer- and subject-masked fashion. The primary endpoint was the maximum voluntary isometric contraction of the quadriceps femoris muscles the morning of postoperative day 2. Equivalence of treatments would be concluded if the 95% confidence interval for the difference fell within the interval of −20% to 20%. Secondary endpoints included active knee extension, passive knee flexion, tolerance to cutaneous electrical current applied over the distal quadriceps tendon, dynamic pain scores, opioid requirements, and ropivacaine consumption. Results Quadriceps maximum voluntary isometric contraction for limbs receiving 0.1% ropivacaine was a mean (SD) of 13 (8) N·m, versus 12 (8) N·m for limbs receiving 0.4% [intra-subject difference of 3 (40) percentage points; 95% CI −10 to 17; p = 0.63]. Because the 95% confidence interval fell within prespecified tolerances, we conclude that the effect of the two concentrations were equivalent. Similarly, there were no statistically significant differences in secondary endpoints. Conclusions For continuous femoral nerve blocks, we found no evidence that local anesthetic concentration and volume influence block characteristics, suggesting that local anesthetic dose (mass) is the primary determinant of perineural infusion effects. PMID:22293719

  18. 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

  19. Role of Netrin-1 Signaling in Nerve Regeneration

    PubMed Central

    Dun, Xin-Peng; Parkinson, David B.

    2017-01-01

    Netrin-1 was the first axon guidance molecule to be discovered in vertebrates and has a strong chemotropic function for axonal guidance, cell migration, morphogenesis and angiogenesis. It is a secreted axon guidance cue that can trigger attraction by binding to its canonical receptors Deleted in Colorectal Cancer (DCC) and Neogenin or repulsion through binding the DCC/Uncoordinated (Unc5) A–D receptor complex. The crystal structures of Netrin-1/receptor complexes have recently been revealed. These studies have provided a structure based explanation of Netrin-1 bi-functionality. Netrin-1 and its receptor are continuously expressed in the adult nervous system and are differentially regulated after nerve injury. In the adult spinal cord and optic nerve, Netrin-1 has been considered as an inhibitor that contributes to axon regeneration failure after injury. In the peripheral nervous system, Netrin-1 receptors are expressed in Schwann cells, the cell bodies of sensory neurons and the axons of both motor and sensory neurons. Netrin-1 is expressed in Schwann cells and its expression is up-regulated after peripheral nerve transection injury. Recent studies indicated that Netrin-1 plays a positive role in promoting peripheral nerve regeneration, Schwann cell proliferation and migration. Targeting of the Netrin-1 signaling pathway could develop novel therapeutic strategies to promote peripheral nerve regeneration and functional recovery. PMID:28245592

  20. The role of nerve microenvironment for neurofibroma development

    PubMed Central

    Liao, Chung-Ping; Pradhan, Sanjay; Chen, Zhiguo; Patel, Amish J.; Booker, Reid C.; Le, Lu Q.

    2016-01-01

    Deregulation of RAS signaling in Neurofibromatosis type 1 (NF1) results in the development of multiple neurofibromas, complex tumor of the peripheral nerves with no effective medical treatment. There is increasing evidences that neurofibroma initiates through loss of NF1 function in the Schwann cell lineage, followed by a cascade of interactions with other cell types in the surrounding tumor microenvironment. In NF1 patients, neurofibromas always develop along peripheral nerves and do not migrate to distant organs, including the central nervous system. In this study, we sought to identify the contributions of these peripheral nerves in neurofibroma formation. Using in vivo and in vitro three-dimensional (3D) culturing system, we show that peripheral nerves are absolutely required for neurofibroma tumorigenesis and report a novel 3D skin raft culture system for neurofibroma formation in vitro to decipher tumor pathogenesis. This interaction between neoplastic Schwann cells and their surrounding neural microenvironment has important implications for understanding early cellular events that dictate tumorigenesis. It also provides fertile ground for the elucidation of intrinsic and extrinsic factors within the nerve microenvironment that likely play essential roles in neurofibroma development and, therefore, viable therapeutic targets in neurofibroma therapy. PMID:27517146

  1. 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.

  2. Anesthetic Efficacy of Different Ropivacaine Concentrations for Inferior Alveolar Nerve Block

    PubMed Central

    El-Sharrawy, Eman; Yagiela, John A

    2006-01-01

    This study was conducted on 72 American Society of Anesthesiologists class 1 patients scheduled for extraction of a mandibular third molar after inferior alveolar nerve block. Each patient was randomly administered one of the following ropivacaine concentrations: 0.75%, 0.5%, 0.375%, or 0.25% (18 patients per group). Onset of block (mean ± SD) was rapid for both 0.75% (1.4 ± 0.4 minutes) and 0.5% (1.7 ± 0.5 minutes) ropivacaine but significantly slower for the 0.375% (4.2 ± 2.5 minutes) and 0.25% (10.7 ± 3.0 minutes) concentrations. Tooth extraction was performed successfully with the 0.5% and 0.75% concentrations, and supplemental injections were not required. Second injections, however, were required with 0.375% ropivacaine. Anesthesia was unsuccessful in 13 patients given 0.25% ropivacaine even after 3 injections. The mean durations of soft tissue anesthesia were 3.3 ± 0.3 hours and 3.0 ± 0.3 hours for the 0.75% and 0.5% concentrations, but significantly shorter with more dilute concentrations. The duration of analgesia showed a similar pattern, with the 0.75% and 0.5% concentrations producing prolonged analgesia of 6.0 ± 0.4 hours and 5.6 ± 0.4 hours. These results indicate that 0.5% and 0.75% concentrations were effective for intraoral nerve blockade, with both a rapid onset and prolonged duration of pain control. PMID:16722277

  3. Anesthetic efficacy of different ropivacaine concentrations for inferior alveolar nerve block.

    PubMed

    El-Sharrawy, Eman; Yagiela, John A

    2006-01-01

    This study was conducted on 72 American Society of Anesthesiologists class 1 patients scheduled for extraction of a mandibular third molar after inferior alveolar nerve block. Each patient was randomly administered one of the following ropivacaine concentrations: 0.75%, 0.5%, 0.375%, or 0.25% (18 patients per group). Onset of block (mean +/- SD) was rapid for both 0.75% (1.4 +/- 0.4 minutes) and 0.5% (1.7 +/- 0.5 minutes) ropivacaine but significantly slower for the 0.375% (4.2 +/- 2.5 minutes) and 0.25% (10.7 +/- 3.0 minutes) concentrations. Tooth extraction was performed successfully with the 0.5% and 0.75% concentrations, and supplemental injections were not required. Second injections, however, were required with 0.375% ropivacaine. Anesthesia was unsuccessful in 13 patients given 0.25% ropivacaine even after 3 injections. The mean durations of soft tissue anesthesia were 3.3 +/- 0.3 hours and 3.0 +/- 0.3 hours for the 0.75% and 0.5% concentrations, but significantly shorter with more dilute concentrations. The duration of analgesia showed a similar pattern, with the 0.75% and 0.5% concentrations producing prolonged analgesia of 6.0 +/- 0.4 hours and 5.6 +/- 0.4 hours. These results indicate that 0.5% and 0.75% concentrations were effective for intraoral nerve blockade, with both a rapid onset and prolonged duration of pain control.

  4. Increased mitochondrial fission and volume density by blocking glutamate excitotoxicity protect glaucomatous optic nerve head astrocytes.

    PubMed

    Ju, Won-Kyu; Kim, Keun-Young; Noh, You Hyun; Hoshijima, Masahiko; Lukas, Thomas J; Ellisman, Mark H; Weinreb, Robert N; Perkins, Guy A

    2015-05-01

    Abnormal structure and function of astrocytes have been observed within the lamina cribrosa region of the optic nerve head (ONH) in glaucomatous neurodegeneration. Glutamate excitotoxicity-mediated mitochondrial alteration has been implicated in experimental glaucoma. However, the relationships among glutamate excitotoxicity, mitochondrial alteration and ONH astrocytes in the pathogenesis of glaucoma remain unknown. We found that functional N-methyl-d-aspartate (NMDA) receptors (NRs) are present in human ONH astrocytes and that glaucomatous human ONH astrocytes have increased expression levels of NRs and the glutamate aspartate transporter. Glaucomatous human ONH astrocytes exhibit mitochondrial fission that is linked to increased expression of dynamin-related protein 1 and its phosphorylation at Serine 616. In BAC ALDH1L1 eGFP or Thy1-CFP transgenic mice, NMDA treatment induced axon loss as well as hypertrophic morphology and mitochondrial fission in astrocytes of the glial lamina. In human ONH astrocytes, NMDA treatment in vitro triggered mitochondrial fission by decreasing mitochondrial length and number, thereby reducing mitochondrial volume density. However, blocking excitotoxicity by memantine (MEM) prevented these alterations by increasing mitochondrial length, number and volume density. In glaucomatous DBA/2J (D2) mice, blocking excitotoxicity by MEM inhibited the morphological alteration as well as increased mitochondrial number and volume density in astrocytes of the glial lamina. However, blocking excitotoxicity decreased autophagosome/autolysosome volume density in both astrocytes and axons in the glial lamina of glaucomatous D2 mice. These findings provide evidence that blocking excitotoxicity prevents ONH astrocyte dysfunction in glaucomatous neurodegeneration by increasing mitochondrial fission, increasing mitochondrial volume density and length, and decreasing autophagosome/autolysosome formation. GLIA 2015;63:736-753.

  5. Increased Mitochondrial Fission and Volume Density by Blocking Glutamate Excitotoxicity Protect Glaucomatous Optic Nerve Head Astrocytes

    PubMed Central

    Ju, Won-Kyu; Kim, Keun-Young; Noh, You Hyun; Hoshijima, Masahiko; Lukas, Thomas J; Ellisman, Mark H; Weinreb, Robert N; Perkins, Guy A

    2015-01-01

    Abnormal structure and function of astrocytes have been observed within the lamina cribrosa region of the optic nerve head (ONH) in glaucomatous neurodegeneration. Glutamate excitotoxicity-mediated mitochondrial alteration has been implicated in experimental glaucoma. However, the relationships among glutamate excitotoxicity, mitochondrial alteration and ONH astrocytes in the pathogenesis of glaucoma remain unknown. We found that functional N-methyl-d-aspartate (NMDA) receptors (NRs) are present in human ONH astrocytes and that glaucomatous human ONH astrocytes have increased expression levels of NRs and the glutamate aspartate transporter. Glaucomatous human ONH astrocytes exhibit mitochondrial fission that is linked to increased expression of dynamin-related protein 1 and its phosphorylation at Serine 616. In BAC ALDH1L1 eGFP or Thy1-CFP transgenic mice, NMDA treatment induced axon loss as well as hypertrophic morphology and mitochondrial fission in astrocytes of the glial lamina. In human ONH astrocytes, NMDA treatment in vitro triggered mitochondrial fission by decreasing mitochondrial length and number, thereby reducing mitochondrial volume density. However, blocking excitotoxicity by memantine (MEM) prevented these alterations by increasing mitochondrial length, number and volume density. In glaucomatous DBA/2J (D2) mice, blocking excitotoxicity by MEM inhibited the morphological alteration as well as increased mitochondrial number and volume density in astrocytes of the glial lamina. However, blocking excitotoxicity decreased autophagosome/autolysosome volume density in both astrocytes and axons in the glial lamina of glaucomatous D2 mice. These findings provide evidence that blocking excitotoxicity prevents ONH astrocyte dysfunction in glaucomatous neurodegeneration by increasing mitochondrial fission, increasing mitochondrial volume density and length, and decreasing autophagosome/autolysosome formation. PMID:25557093

  6. 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.

  7. Heparin blocks functional innervation of cultured human muscle by rat motor nerve.

    PubMed

    Marš, Tomaž; King, Michael P; Miranda, Armand F; Grubič, Zoran

    2000-01-01

    In vitro innervated human muscle is the only experimental model to study synaptogenesis of the neuromuscular junction in humans. Cultured human muscle never contracts spontaneously but will if innervated and therefore is a suitable model to study the effects of specific neural factors on the formation of functional neuromuscular contacts. Here, we tested the hypothesis that nerve derived factor agrin is essential for the formation of functional synapses between human myotubes and motoneurons growing from the explant of embryonic rat spinal cord. Agrin actions were blocked by heparin and the formation of functional neuromuscular contacts was quantitated. At a heparin concentration of 25 μg/ml, the number of functional contacts was significantly reduced. At higher concentrations, formation of such contacts was blocked completely. Except at the highest heparin concentrations (150 μg/ml) neuronal outgrowth was normal indicating that blockade of neuromuscular junction formation was not due to neuronal dysfunction. Our results are in accord with the concept that binding of neural agrin to the synaptic basal lamina is essential for the formation of functional neuromuscular junctions in the human muscle.

  8. Heparin blocks functional innervation of cultured human muscle by rat motor nerve.

    PubMed

    Mars, T; King, M P; Miranda, A F; Grubic, Z

    2000-01-01

    In vitro innervated human muscle is the only experimental model to study synaptogenesis of the neuromuscular junction in humans. Cultured human muscle never contracts spontaneously but will if innervated and therefore is a suitable model to study the effects of specific neural factors on the formation of functional neuromuscular contacts. Here, we tested the hypothesis that nerve derived factor agrin is essential for the formation of functional synapses between human myotubes and motoneurons growing from the explant of embryonic rat spinal cord. Agrin actions were blocked by heparin and the formation of functional neuromuscular contacts was quantitated. At a heparin concentration of 25 microg/ml, the number of functional contacts was significantly reduced. At higher concentrations, formation of such contacts was blocked completely. Except at the highest heparin concentrations (150 microg/ml) neuronal outgrowth was normal indicating that blockade of neuromuscular junction formation was not due to neuronal dysfunction. Our results are in accord with the concept that binding of neural agrin to the synaptic basal lamina is essential for the formation of functional neuromuscular junctions in the human muscle.

  9. A comparison between acute pressure block of the sciatic nerve and acupressure: methodology, analgesia, and mechanism involved

    PubMed Central

    Luo, Danping; Wang, Xiaolin; He, Jiman

    2013-01-01

    Acupressure is an alternative medicine methodology that originated in ancient China. Treatment effects are achieved by stimulating acupuncture points using acute pressure. Acute pressure block of the sciatic nerve is a newly reported analgesic method based on a current neuroscience concept: stimulation of the peripheral nerves increases the pain threshold. Both methods use pressure as an intervention method. Herein, we compare the methodology and mechanism of these two methods, which exhibit several similarities and differences. Acupressure entails variation in the duration of manipulation, and the analgesic effect achieved can be short-or long-term. The acute effect attained with acupressure presents a scope that is very different from that of the chronic effect attained after long-term treatment. This acute effect appears to have some similarities to that achieved with acute pressure block of the sciatic nerve, both in methodology and mechanism. More evidence is needed to determine whether there is a relationship between the two methods. PMID:23983488

  10. Ultrasound-guided ilioinguinal and iliohypogastric nerve block, a comparison with the conventional technique: An observational study

    PubMed Central

    Khedkar, Sunita Milind; Bhalerao, Pradnya Milind; Yemul-Golhar, Shweta Rahul; Kelkar, Kalpana Vinod

    2015-01-01

    Background: The conventional technique of ilioinguinal and iliohypogastric nerve block may be associated with drug toxicity, block failure and needs large drug volume. The ultrasound-guided (USG) nerve block enables accurate needle positioning that may reduce the chances of drug toxicity, drug dose and block failure. Aim: In this study, we compared the onset and duration of the motor and sensory nerve block, the drug volume required and time to rescue analgesic between USG and conventional technique. Settings and Design: Sixty male patients aged between 18 and 60 years, belonging to American society of Anesthesiology I-II, scheduled for inguinal hernia repair were enrolled in this prospective study and were randomly allocated into two groups of thirty each by computerized method. Materials and Methods: Group A patients received hernia block by conventional method using 0.75% ropivacaine 15 ml, and Group B patients were given the block guided by ultrasound using 0.75% ropivacaine, till the nerves were surrounded on all sides by the drug. Statistical Analysis: The data were analyzed using two independent sample t-tests for demographic and hemodynamic parameters. Nonparametric test (Mann-Whitney U-test) was used to find the significance between visual analog scale. Results: There was significantly early onset of sensory block in Group B 14.03 ± 2.82 min as compared to Group A 15.57 ± 1.52 min (P = 0.047). The onset of motor block was also earlier in Group B 19.40 ± 2.85 min as compared to Group A 20.67 ± 1.90 min. The time to rescue analgesia was more in Group B 7.22 ± 0.97 h as compared to Group A 6.80 ± 0.70 h (P = 0.062). The volume of drug required was less with ultrasound guided block. Conclusions: Ultrasound-guided hernia block thus has the advantage of early onset, less dose requirement and increase in time to rescue analgesia. PMID:26240549

  11. 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

  12. Comparative evaluation of femoral nerve block and intravenous fentanyl for positioning during spinal anaesthesia in surgery of femur fracture

    PubMed Central

    Jadon, Ashok; Kedia, Sunil Kumar; Dixit, Shreya; Chakraborty, Swastika

    2014-01-01

    Background: Spinal anaesthesia is the preferred technique to fix fracture of the femur. Extreme pain does not allow ideal positioning for this procedure. Intravenous fentanyl and femoral nerve block are commonly used techniques to reduce the pain during position for spinal anaesthesia however; results are conflicting regarding superiority of femoral nerve block over intravenous fentanyl. Aims: We conducted this study to compare the analgesic effect provided by femoral nerve block (FNB) and intra- venous (IV) fentanyl prior to positioning for central neuraxial block in patients undergoing surgery for femur fracture. Patients and Methods: In this randomized prospective study 60 patients scheduled for fracture femur operation under spinal were included. Patients were distributed in two groups through computer generated random numbers table; Femoral nerve block group (FNB) and Intravenous fentanyl group (FENT). In FNB group patients received FNB guided by a peripheral nerve stimulator (Stimuplex; B Braun, Melsungen, AG) 5 minutes prior to positioning. 20mL, 1.5% lidocaine with adrenaline (1:200,000) was injected incrementally after a negative aspiration test. Patients in the fentanyl group received injection fentanyl 1 μg/kg IV 5 mins prior to positioning. Spinal block was performed and pain scores before and during positioning were recorded. Statistical analysis was done with Sigmaplot version-10 computer software. Student t-test was applied to compare the means and P < 0.05 was taken as significant. Results: VAS during positioning in group FNB: 0.57 ± 0.31 versus FENT 2.53 ± 1.61 (P = 0.0020). Time to perform spinal anesthesia in group FNB: 15.33 ± 1.64 min versus FENT 19.56 ± 3.09 min (P = 0.000049). Quality of patient positioning for spinal anesthesia in group FNB 2.67± 0.606 versus FENT 1.967 ± 0.85 (P = 0.000027). Patient acceptance was less in group FENT (P = 0.000031). Conclusion: Femoral nerve block provides better analgesia, patient satisfaction and

  13. 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

  14. 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.

  15. 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

  16. 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

  17. Occipital nerve block is effective in craniofacial neuralgias but not in idiopathic persistent facial pain.

    PubMed

    Jürgens, T P; Müller, P; Seedorf, H; Regelsberger, J; May, A

    2012-04-01

    Occipital nerve block (ONB) has been used in several primary headache syndromes with good results. Information on its effects in facial pain is sparse. In this chart review, the efficacy of ONB using lidocaine and dexamethasone was evaluated in 20 patients with craniofacial pain syndromes comprising 8 patients with trigeminal neuralgia, 6 with trigeminal neuropathic pain, 5 with persistent idiopathic facial pain and 1 with occipital neuralgia. Response was defined as an at least 50% reduction of original pain. Mean response rate was 55% with greatest efficacy in trigeminal (75%) and occipital neuralgia (100%) and less efficacy in trigeminal neuropathic pain (50%) and persistent idiopathic facial pain (20%). The effects lasted for an average of 27 days with sustained benefits for 69, 77 and 107 days in three patients. Side effects were reported in 50%, albeit transient and mild in nature. ONBs are effective in trigeminal pain involving the second and third branch and seem to be most effective in craniofacial neuralgias. They should be considered in facial pain before more invasive approaches, such as thermocoagulation or vascular decompression, are performed, given that side effects are mild and the procedure is minimally invasive.

  18. Relationship between ventral lumbar disc protrusion and contrast medium leakage during sympathetic nerve block.

    PubMed

    Tazawa, Toshiharu; Kamiya, Yoshinori; Takamori, Mina; Ogawa, Ken-Ichi; Goto, Takahisa

    2015-02-01

    Ventral disc protrusions have been neglected because they are asymptomatic. Lumbar sympathetic nerve block (LSNB) is one of the clinical choices for refractory low back pain treatment. Leakage of the contrast medium may occur and lead to complications, especially when using a neurolytic agent. In this study, we retrospectively reviewed the magnetic resonance images (MRIs) of 52 consecutive patients with refractory low back pain due to lumbar spinal canal stenosis who underwent LSNB, and graded ventral disc protrusion at the L1/2 to L5/S1 vertebral discs on a three-point scale (grade 0 = no protrusion, grade 1 = protrusion without migration, grade 2 = protrusion with migration). We also determined if there was leakage of contrast medium in LSNB. Ventral disc protrusion was observed in all patients, and 75 % (39/52) had grade 2 protrusion in the L1/2-L3/4 vertebral discs. Moreover, the incidence of contrast medium leakage was significantly higher at the vertebrae that had grade 2 protrusion than at those with less protrusion. We revealed a higher incidence of ventral disc protrusion of the lumbar vertebrae than previously reported, and that the incidence of leakage in LSNB increased when ventral disc protrusion was present. To avoid complications, attention should be paid to ventral disc protrusions before performing LSNB.

  19. Sciatic-femoral nerve block with bupivacaine in goats undergoing elective stifle arthrotomy.

    PubMed

    Adami, Chiara; Bergadano, Alessandra; Bruckmaier, Rupert M; Stoffel, Michael H; Doherr, Marcus G; Spadavecchia, Claudia

    2011-04-01

    The aim of this study was to describe the sciatic-femoral nerve block (SFNB) in goats and to evaluate the peri-operative analgesia when the goats underwent stifle arthrotomy. The animals were randomly assigned to one of four treatment groups: groups 0.25, 0.5 and 0.75 received 0.25%, 0.5% and 0.75% of bupivacaine, respectively, while group C (control group) received 0.9% NaCl. In all groups, the volume administered was 0.2 mL/kg. Intra-operatively, the proportion of animals receiving rescue propofol was significantly lower in groups 0.5 and 0.75, compared to group C. Post-operatively, the visual analogue scale (VAS) and total pain score were significantly higher in group C than in the other groups. Group 0.75 had the highest percentage of animals showing motor blockade. SFNB performed with bupivacaine resulted in better intra- and post-operative analgesia than SFNB performed with saline. Compared to the other concentrations, 0.5% bupivacaine resulted in satisfactory analgesia with acceptable side effects.

  20. Liposomal Bupivacaine vs Interscalene Nerve Block for Pain Control After Shoulder Arthroplasty: A Retrospective Cohort Analysis.

    PubMed

    Hannan, Casey V; Albrecht, Matthew J; Petersen, Steve A; Srikumaran, Uma

    The aim of this study was to compare liposomal bupivacaine and interscalene nerve block (ISNB) for analgesia after shoulder arthroplasty. We compared 37 patients who received liposomal bupivacaine vs 21 who received ISNB after shoulder arthroplasty by length of hospital stay (LOS), opioid consumption, and postoperative pain. Pain was the same in both groups for time intervals of 1 hour and 8 to 14 hours postoperatively. Compared with ISNB patients, liposomal bupivacaine patients reported less pain at 18 to 24 hours (P = .001) and 27 to 36 hours (P = .029) and had lower opioid consumption on postoperative days 2 (P = .001) and 3 (P = .002). Mean LOS for liposomal bupivacaine patients was 46 ± 20 hours vs 57 ± 14 hours for ISNB patients (P = .012). Sixteen of 37 liposomal bupivacaine patients vs 2 of 21 ISNB patients were discharged on the first postoperative day (P = .010). Liposomal bupivacaine was associated with less pain, less opioid consumption, and shorter hospital stays after shoulder arthroplasty compared with ISNB.

  1. Management of pudendal neuralgia using ultrasound-guided pulsed radiofrequency: a report of two cases and discussion of pudendal nerve block techniques.

    PubMed

    Hong, Myong-Joo; Kim, Yeon-Dong; Park, Jeong-Ki; Hong, Hyon-Joo

    2016-04-01

    Pudendal neuralgia is characterized by chronic pain or discomfort in the area innervated by the pudendal nerve, with no obvious cause. A successful pudendal nerve block is crucial for the diagnosis of pudendal neuralgia. Blind or fluoroscopy-guided pudendal nerve blocks have been conventionally used for diagnosis and treatment; however, ultrasound-guided pudendal nerve blocks were also reported recently. With regard to the achievement of long-term effects, although pulsed radiofrequency performed under fluoroscopic guidance has been reported, that performed under ultrasound guidance is not well reported. This report describes two cases of pudendal neuralgia that were successfully managed using ultrasound-guided pulsed radiofrequency and presents a literature review of pudendal nerve block techniques. However, in the management of chronic neuropathic pain, physicians should keep in mind that the placebo effect related to invasive approaches must not be neglected.

  2. Effect of Combined Single-Injection Femoral Nerve Block and Patient-Controlled Epidural Analgesia in Patients Undergoing Total Knee Replacement

    PubMed Central

    Lee, Ae-Ryung; Choi, Duck-Hwan; Choi, Soo-Joo; Hahm, Tae-Soo; Kim, Ga-Hyun; Moon, Young-Hwan

    2011-01-01

    Purpose Total knee replacement is one of the most painful orthopedic procedures, and effective pain relief is essential for early mobility and discharge from hospital. The aim of this study was to evaluate whether addition of single-injection femoral nerve block to epidural analgesia would provide better postoperative pain control, compared to epidural analgesia alone, after total knee replacement. Materials and Methods Thirty-eight patients received a single-injection femoral nerve block with 0.25% levobupivacaine (30 mL) combined with epidural analgesia (femoral nerve block group) and 40 patients received epidural analgesia alone (control group). Pain intensity and volume of patient-controlled epidural analgesia medication and rescue analgesic requirements were measured in the first 48 hours after surgery at three time periods; 0-6 hours, 6-24 hours, and 24-48 hours. Also, side effects such as nausea, vomiting, and pruritus were evaluated. Results Median visual analog scale at rest and movement was significantly lower until 48 hours in the femoral nerve block group. Patient-controlled epidural analgesia volume was significantly lower throughout the study period, however, rescue analgesia requirements were significantly lower only up to 6 hours in the femoral nerve block group. The incidences of nausea and vomiting and rescue antiemetic requirement were significantly lower in the femoral nerve block group up to 6 hours. Conclusion The combination of femoral nerve block with epidural analgesia is an effective pain management regimen in patients undergoing unilateral total knee replacement. PMID:21155047

  3. 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

  4. The bee venom peptide tertiapin underlines the role of IKACh in acetylcholine-induced atrioventricular blocks

    PubMed Central

    Drici, Milou-Daniel; Diochot, Sylvie; Terrenoire, Cécile; Romey, Georges; Lazdunski, Michel

    2000-01-01

    Acetylcholine (ACh) is an important neuromodulator of cardiac function that is released upon stimulation of the vagus nerve. Despite numerous reports on activation of IKACh by acetylcholine in cardiomyocytes, it has yet to be demonstrated what role this channel plays in cardiac conduction. We studied the effect of tertiapin, a bee venom peptide blocking IKACh, to evaluate the role of IKACh in Langendorff preparations challenged with ACh.ACh (0.5 μM) reproducibly and reversibly induced complete atrioventricular (AV) blocks in retroperfused guinea-pig isolated hearts (n=12).Tertiapin (10 to 300 nM) dose-dependently and reversibly prevented the AV conduction decrements and the complete blocks in unpaced hearts (n=8, P<0.01).Tertiapin dose-dependently blunted the ACh-induced negative chronotropic response from an ACh-induced decrease in heart rate of 39±16% in control conditions to 3±3% after 300 nM tertiapin (P=0.01). These effects were not accompanied by any significant change in QT intervals.Tertiapin blocked IKACh with an IC50 of 30±4 nM with no significant effect on the major currents classically associated with cardiac repolarisation process (IKr, IKs, Ito1, Isus, IK1 or IKATP) or AV conduction (INa and ICa(L)).In summary, tertiapin prevents dose-dependently ACh-induced AV blocks in mammalian hearts by inhibiting IKACh. PMID:11015309

  5. Factors Associated With Risk of Neurologic Complications After Peripheral Nerve Blocks: A Systematic Review.

    PubMed

    Sondekoppam, Rakesh V; Tsui, Ban C H

    2017-02-01

    The onset of neurologic complications after regional anesthesia is a complex process and may result from an interaction of host, agent, and environmental risk factors. The purpose of this systematic review was examine the qualitative evidence relating to various risk factors implicated in neurologic dysfunction after peripheral nerve block (PNB). The MEDLINE, OVID, and EMBASE databases were primary sources for literature. Cochrane, LILACS, DARE, IndMed, ERIC, NHS, and HTA via Centre for Reviews and Dissemination (CRD; York University) databases were searched for additional unique results. Randomized controlled studies, case-control studies, cohort studies, retrospective reviews, and case reports/case series reporting neurologic outcomes after PNB were included. Relevant, good-quality systematic reviews were also eligible. Human and animal studies evaluating factors important for neurologic outcomes were assessed separately. Information on study design, outcomes, and quality was extracted and reviewed independently by the 2 review authors. An overall rating of the quality of evidence was assigned using GRADE (Grading of Recommendations Assessment, Development and Evaluation) criteria. Relevant full-text articles were separated based on type (prospective, retrospective, and nonhuman studies). Strengths of association were defined as high, moderate, inconclusive, or inadequate based on study quality and direction of association. The evidence from 77 human studies was reviewed to assess various host, agent, and environmental factors that have been implicated as possible risks. Most of the available evidence regarding the injurious effects of the 3 cardinal agents of mechanical insult, pressure, and neurotoxicity was extracted from animal studies (42 studies). Among the risk factors investigated in humans, block type had a strong association with neurologic outcome. Intraneural injection, which seems to occur commonly with PNBs, showed an inconsistent direction of

  6. Assessment of Anteroposterior Subpedicular Approach and Oblique Scotty Dog Subpedicular Approach for Selective Nerve Root Block

    PubMed Central

    Yeh, Yu-Cheng; Luo, Chi-An; Joey-Tan, Kit-Yang

    2017-01-01

    Background The technique used to administer a selective nerve root block (SNRB) varies depending on individual expertise. Both the anteroposterior (AP) subpedicular approach and oblique Scotty dog subpedicular approach are widely practiced. However, the literature does not provide a clear consensus regarding which approach is more suitable. Hence, we decided to analyse the procedural parameters and clinical outcomes following SNRBs using these two approaches. Methods Patients diagnosed with a single lumbar herniated intervertebral disc (HIVD) refractory to conservative management but not willing for immediate surgery were selected for a prospective nonrandomized comparative study. An SNRB was administered as a therapeutic alternative using the AP subpedicular approach in one group (n = 25; mean age, 45 ± 5.4 years) and the oblique Scotty dog subpedicular approach in the other group (n = 22; mean age, 43.8 ± 4.7 years). Results were compared in terms of the duration of the procedure, the number of C-arm exposures, accuracy, pain relief, functional outcome and the duration of relief. Results Our results suggest that the oblique Scotty dog subpedicular approach took a significantly longer duration (p = 0.02) and a greater number of C-arm exposures (p = 0.001). But, its accuracy of needle placement was 95.5% compared to only 72% using the AP subpedicular approach (p = 0.03). There was no significant difference in terms of clinical outcomes between these approaches. Conclusions The AP subpedicular approach was simple and facile, but the oblique Scotty dog subpedicular approach was more accurate. However, a brief window period of pain relief was achieved irrespective of the approaching technique used. PMID:28261430

  7. Role of the vegus nerve in epilepsy (image)

    MedlinePlus

    The vagus nerves branch off the brain on either side of the head and travel down the neck, along the ... the body, and affect swallowing and speech. The vagus nerves also connect to parts of the brain involved ...

  8. Repairing Peripheral Nerves: Is there a Role for Carbon Nanotubes?

    PubMed

    Oprych, Karen M; Whitby, Raymond L D; Mikhalovsky, Sergey V; Tomlins, Paul; Adu, Jimi

    2016-06-01

    Peripheral nerve injury continues to be a major global health problem that can result in debilitating neurological deficits and neuropathic pain. Current state-of-the-art treatment involves reforming the damaged nerve pathway using a nerve autograft. Engineered nerve repair conduits can provide an alternative to the nerve autograft avoiding the inevitable tissue damage caused at the graft donor site. Commercially available nerve repair conduits are currently only considered suitable for repairing small nerve lesions; the design and performance of engineered conduits requires significant improvements to enable their use for repairing larger nerve defects. Carbon nanotubes (CNTs) are an emerging novel material for biomedical applications currently being developed for a range of therapeutic technologies including scaffolds for engineering and interfacing with neurological tissues. CNTs possess a unique set of physicochemical properties that could be useful within nerve repair conduits. This progress report aims to evaluate and consolidate the current literature pertinent to CNTs as a biomaterial for supporting peripheral nerve regeneration. The report is presented in the context of the state-of-the-art in nerve repair conduit design; outlining how CNTs may enhance the performance of next generation peripheral nerve repair conduits.

  9. Potassium channel blocking actions of beta-bungarotoxin and related toxins on mouse and frog motor nerve terminals.

    PubMed Central

    Rowan, E. G.; Harvey, A. L.

    1988-01-01

    1. beta-Bungarotoxin and other snake toxins with phospholipase activity augment acetylcholine release evoked from mouse motor nerve terminals before they produce blockade. This action of the toxins is independent of their phospholipase A2 activity, but the underlying mechanism for the facilitation of release is unclear. To determine whether the toxins affect ionic currents at motor nerve terminals, extracellular recordings were made from perineural sheaths of motor nerves innervating mouse triangularis sterni muscles. 2. Perineural waveforms had a characteristic shape, with two major negative deflections, the first being associated with nodal Na+ currents and the second with terminal K+ currents. Block of the K+ currents revealed a Ca2+-dependent component. 3. During the facilitatory phase of its action, beta-bungarotoxin (150 nM) reduced the second negative component of the perineural waveform by 30-50%. 4. The reduction could be a consequence of a decreased K+ ion contribution or of an increase in the current carried by Ca2+. As beta-bungarotoxin had similar effects in solutions which contained no added Ca2+, it is unlikely to be acting on the Ca2+ current. Also, it is unlikely to be blocking the Ca2+-activated K+ current, which is suppressed in zero Ca2+ conditions. 5. Other prejunctionally active snake toxins (taipoxin, notexin and crotoxin) had similar effects to those of beta-bungarotoxin, but a similar basic phospholipase of low toxicity from cobra venom had no effect. 6. Thus, beta-bungarotoxin and related toxins block a fraction of the K+ current in the motor nerve terminals of mouse preparations.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3263160

  10. Fluoroscopically guided extraforaminal cervical nerve root blocks: analysis of epidural flow of the injectate with respect to needle tip position.

    PubMed

    Shipley, Kyle; Riew, K Daniel; Gilula, Louis A

    2014-02-01

    Study Design Retrospective evaluation of consecutively performed fluoroscopically guided cervical nerve root blocks. Objective To describe the incidence of injectate central epidural flow with respect to needle tip position during fluoroscopically guided extraforaminal cervical nerve root blocks (ECNRBs). Methods Between February 19, 2003 and June 11, 2003, 132 consecutive fluoroscopically guided ECNRBs performed with contrast media in the final injected material (injectate) were reviewed on 95 patients with average of 1.3 injections per patient. Fluoroscopic spot images documenting the procedure were obtained as part of standard quality assurance. An independent observer not directly involved in the procedures retrospectively reviewed the images, and the data were placed into a database. Image review was performed to determine optimal needle tip positioning for injectate epidural flow. Results Central epidural injectate flow was obtained in only 28.9% of injections with the needle tip lateral to midline of the lateral mass (zone 2). 83.8% of injectate went into epidural space when the needle tip was medial to midline of the lateral mass (zone 3). 100% of injectate flowed epidurally when the needle tip was medial to or at the medial cortex of the lateral mass (zone 4). There was no statistically significant difference with regards to central epidural flow and the needle tip position on lateral view. Conclusion To ensure central epidural flow with ECNRBs one must be prepared to pass the needle tip medial to midplane of the lateral mass or to medial cortex of the lateral mass. Approximately 16% of ECNRBs with needle tip medial to midline of the lateral mass did not flow into epidural space. One cannot claim a nerve block is an epidural block unless epidural flow of injectate is observed.

  11. Effect of massage on the efficacy of the mental and incisive nerve block.

    PubMed

    Jaber, A; Whitworth, J M; Corbett, I P; Al-Baqshi, B; Jauhar, S; Meechan, J G

    2013-01-01

    The purpose of this trial was to assess the effect of soft tissue massage on the efficacy of the mental and incisive nerve block (MINB). Thirty-eight volunteers received MINB of 2.2 mL of 2% lidocaine with 1 : 80,000 epinephrine on 2 occasions. At one visit the soft tissue overlying the injection site was massaged for 60 seconds (active treatment). At the other visit the crowns of the mandibular premolar teeth were massaged (control treatment). Order of treatments was randomized. An electronic pulp tester was used to measure pulpal anesthesia in the ipsilateral mandibular first molar, a premolar, and lateral incisor teeth up to 45 minutes following the injection. The efficacy of pulp anesthesia was determined by 2 methods: (a) by quantifying the number of episodes with no response to maximal electronic pulp stimulation after each treatment, and (b) by quantifying the number of volunteers with no response to maximal pulp stimulation (80 reading) on 2 or more consecutive tests, termed anesthetic success. Data were analyzed by McNemar, Mann-Whitney, and paired-samples t tests. Anesthetic success was 52.6% for active and 42.1% for control treatment for lateral incisors, 89.5 and 86.8% respectively for premolars, and 50.0 and 42.1% respectively for first molars (P = .344, 1.0, and .508 respectively). There were no significant differences in the number of episodes of negative response to maximum pulp tester stimulation between active and control massage. A total of 131 episodes were recorded after both active and control massage in lateral incisors (McNemar test, P = 1.0), 329 (active) versus 316 (control) episodes in the premolars (McNemar test, P = .344), and 119 (active) versus 109 (control) episodes respectively for first molars (McNemar test, P = .444). Speed of anesthetic onset and discomfort did not differ between treatments. We concluded that soft tissue massage after MINB does not influence anesthetic efficacy.

  12. 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

  13. 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

  14. Effect of sublingual triazolam on the success of inferior alveolar nerve block in patients with irreversible pulpitis.

    PubMed

    Lindemann, Matthew; Reader, Al; Nusstein, John; Drum, Melissa; Beck, Mike

    2008-10-01

    The purpose of this prospective, randomized, double-blind, placebo-controlled study was to determine the effect of the administration of sublingual triazolam on the success of the inferior alveolar nerve (IAN) block in patients experiencing irreversible pulpitis. Fifty-eight emergency patients diagnosed with irreversible pulpitis of a mandibular posterior tooth randomly received, in a double-blind manner, an identical sublingual tablet of either 0.25 mg of triazolam or a placebo 30 minutes before administration of a conventional IAN block. Access was begun 15 minutes after completion of the IAN block, and all patients had profound lip numbness. Success was defined as no or mild pain (visual analog scale recordings) on access or initial instrumentation. The success rate for the IAN block was 43% with triazolam and 57% with the placebo, with no significant difference (P = .43) between the 2 groups. For mandibular posterior teeth, triazolam in a sublingual dose of 0.25 mg did not result in an increase in success of the IAN block in patients with irreversible pulpitis. Therefore, when using conscious sedation, profound local anesthesia is still required to eliminate the sensation of pain during endodontic treatment for patients with irreversible pulpitis.

  15. Effects of perineural administration of dexmedetomidine in combination with bupivacaine in a femoral-sciatic nerve block

    PubMed Central

    Helal, Safaa M.; Eskandr, Ashraf M.; Gaballah, Khaled M.; Gaarour, Ihab S.

    2016-01-01

    Background and Aim: Perineural administration of dexmedetomidine, a α2-adrenoceptor agonist, prolongs the duration of analgesia. We hypothesized that adding dexmedetomidine to bupivacaine would prolong postoperative analgesia after below knee surgery. Materials and Methods: After ethical approval, 60 patients scheduled for below knee surgery under combined femoral-sciatic nerve block were randomly allocated into two groups to have their block performed using bupivacaine 0.5% alone (group B) or bupivacaine 0.5% combined with 100 μg bupivacaine-dexmedetomidine (group BD). Motor and sensory block onset times; durations of blockades and analgesia were recorded. Results: Sensory and motor block onset times were shorter by 20% in group BD than in group B (P < 0.01). Sensory and motor blockade durations were longer in group BD (+45% and +40%, respectively) than in group B (P < 0.01). Duration of analgesia was longer in group BD by 75% than in group B (P < 0.01). Systolic, diastolic arterial blood pressure levels, and heart rate were significantly less in group BD, six patients in group BD, and no patients in group B developed bradycardia (P < 0.05). Conclusion: The addition of dexmedetomidine 100 μg to bupivacaine 0.5% during ultrasound-guided combined femoral and sciatic block for below knee surgery was associated with a prolonged duration of analgesia. However, this may be associated with significant bradycardia requiring treatment. PMID:26955305

  16. Effects of applying nerve blocks to prevent postherpetic neuralgia in patients with acute herpes zoster: a systematic review and meta-analysis

    PubMed Central

    Kim, Hyun Jung; Ahn, Hyeong Sik; Lee, Jae Young; Choi, Seong Soo; Cheong, Yu Seon; Kwon, Koo; Yoon, Syn Hae

    2017-01-01

    Background Postherpetic neuralgia (PHN) is a common and painful complication of acute herpes zoster. In some cases, it is refractory to medical treatment. Preventing its occurrence is an important issue. We hypothesized that applying nerve blocks during the acute phase of herpes zoster could reduce PHN incidence by attenuating central sensitization and minimizing nerve damage and the anti-inflammatory effects of local anesthetics and steroids. Methods This systematic review and meta-analysis evaluates the efficacy of using nerve blocks to prevent PHN. We searched the MEDLINE, EMBASE, Cochrane Library, ClinicalTrials.gov and KoreaMed databases without language restrictions on April, 30 2014. We included all randomized controlled trials performed within 3 weeks after the onset of herpes zoster in order to compare nerve blocks vs active placebo and standard therapy. Results Nine trials were included in this systematic review and meta-analysis. Nerve blocks reduced the duration of herpes zoster-related pain and PHN incidence of at 3, 6, and 12 months after final intervention. Stellate ganglion block and single epidural injection did not achieve positive outcomes, but administering paravertebral blockage and continuous/repeated epidural blocks reduced PHN incidence at 3 months. None of the included trials reported clinically meaningful serious adverse events. Conclusions Applying nerve blocks during the acute phase of the herpes zoster shortens the duration of zoster-related pain, and somatic blocks (including paravertebral and repeated/continuous epidural blocks) are recommended to prevent PHN. In future studies, consensus-based PHN definitions, clinical cutoff points that define successful treatment outcomes and standardized outcome-assessment tools will be needed. PMID:28119767

  17. Comparison of Nerve Stimulation-guided Axillary Brachial Plexus Block, Single Injection versus Four Injections: A Prospective Randomized Double-blind Study

    PubMed Central

    Badiger, Santoshi V.; Desai, Sameer N.

    2017-01-01

    Background: A variety of techniques have been described for the axillary block using nerve stimulator, either with single injection, two, three, or four separate injections. Identification of all the four nerves is more difficult and time-consuming than other methods. Aims: Aim of the present study is to compare success rate, onset, and duration of sensory and motor anesthesia of axillary block using nerve stimulator, either with single injection after identification of any one of the four nerves or four separate injections following identification of each of nerve. Setting and Design: Prospective, randomized, double-blind study. Patients undergoing forearm and hand surgeries under axillary block. Methodology: One hundred patients, aged 18–75 years, were randomly allocated into two groups of 50 each. Axillary block was performed under the guidance of nerve stimulator with a mixture of 18 ml of 1.5% lignocaine and 18 ml of 0.5% bupivacaine. In the first group (n = 50), all 36 ml of local anesthetic was injected after the identification of motor response to any one of the nerves and in Group 2, all the four nerves were identified by the motor response, and 9 ml of local anesthetic was injected at each of the nerves. The success rate of the block, onset, and duration of sensory and motor block was assessed. Statistical Analysis: Categorical variables were compared using the Chi-square test, and continuous variables were compared using independent t-test. Results: The success rate of the block with four injection technique was higher compared to single-injection technique (84% vs. 56%, P = 0.02). Four injection groups had a faster onset of sensory and motor block and prolonged duration of analgesia compared to single-injection group (P < 0.001). There were no significant differences in the incidence of accidental arterial puncture and hemodynamic parameter between the groups. Conclusion: Identification of all the four nerves produced higher success rate and better

  18. Automatic Segmentation and Probe Guidance for Real-Time Assistance of Ultrasound-Guided Femoral Nerve Blocks.

    PubMed

    Smistad, Erik; Iversen, Daniel Høyer; Leidig, Linda; Lervik Bakeng, Janne Beate; Johansen, Kaj Fredrik; Lindseth, Frank

    2017-01-01

    Ultrasound-guided regional anesthesia can be challenging, especially for inexperienced physicians. The goal of the proposed methods is to create a system that can assist a user in performing ultrasound-guided femoral nerve blocks. The system indicates in which direction the user should move the ultrasound probe to investigate the region of interest and to reach the target site for needle insertion. Additionally, the system provides automatic real-time segmentation of the femoral artery, the femoral nerve and the two layers fascia lata and fascia iliaca. This aids in interpretation of the 2-D ultrasound images and the surrounding anatomy in 3-D. The system was evaluated on 24 ultrasound acquisitions of both legs from six subjects. The estimated target site for needle insertion and the segmentations were compared with those of an expert anesthesiologist. Average target distance was 8.5 mm with a standard deviation of 2.5 mm. The mean absolute differences of the femoral nerve and the fascia segmentations were about 1-3 mm.

  19. The role of peripheral nerves in urodele limb regeneration.

    PubMed

    Stocum, David L

    2011-09-01

    Nerve axons and the apical epidermal cap (AEC) are both essential for the formation of an accumulation blastema by amputated limbs of urodele salamanders. The AEC forms in the absence of axons, but is not maintained, and blastema formation fails. Growth stages of the blastema become nerve-independent for morphogenesis, but remain dependent on the nerve for blastema growth. Denervated growth stage blastemas form smaller than normal skeletal parts, owing to diminished mitosis, but form the full proximodistal array of skeletal elements. This difference in nerve dependency of morphogenesis and proliferation is hypothesized to be the result of a dependence of the AEC on nerves for blastema cell proliferation but not for blastema morphogenesis. Regenerating axons induce the synthesis and secretion of the anterior gradient protein (AGP) by distal Schwann cells during dedifferentiation and by the gland cells of the AEC during blastema growth stages. AGP promotes the regeneration of a denervated limb to digit stages when electroporated into the limb during dedifferentiation. Once a critical mass of blastema cells has been attained, the blastema can undergo morphogenesis in the absence of the nerve, but the regenerate will be a miniature, because the nerve is no longer inducing the AEC to carry out its AGP-mediated proliferative function. AGP expression by both Schwann cells and the AEC is induced by axons, but the nature of the inductive agent is unclear.

  20. The anesthetic considerations while performing supraclavicular brachial plexus block in emergency surgical patients using a nerve stimulator.

    PubMed

    Tantry, Thrivikrama Padur; Shetty, Pramal; Shetty, Rithesh; Shenoy, Sunil P

    2015-01-01

    Regional anesthesia is favored in patients who undergo emergency extremity (limb) surgery, and specifically so in the absence of fasting status. In the absence of ultrasonic guidance, the nerve stimulator still remains a valuable tool in performing a brachial block, but its use is difficult in an emergency surgical patient and greater cautious approach is essential. We identified the supraclavicular plexus by the nerve stimulation-motor response technique as follows. Anterior chest muscles contractions, diaphragmatic contraction, deltoid contractions, and posterior shoulder girdle muscle contractions when identified were taken as "negative response" with decreasing stimulating current. A forearm muscle contraction, especially "wrist flexion" and "finger flexion" at 0.5 mA of current was taken as "positive response." If no positive response was identified, the "elbow flexion" was considered as the final positive response for successful drug placement. The series of patients had difficulty for administering both general and regional anesthesia and we considered them as complex scenarios. The risk of the block failure was weighed heavily against the benefits of its success. The described series includes patients who had successful outcomes in the end and the techniques, merits, and risks are highlighted.

  1. The anesthetic considerations while performing supraclavicular brachial plexus block in emergency surgical patients using a nerve stimulator

    PubMed Central

    Tantry, Thrivikrama Padur; Shetty, Pramal; Shetty, Rithesh; Shenoy, Sunil P.

    2015-01-01

    Regional anesthesia is favored in patients who undergo emergency extremity (limb) surgery, and specifically so in the absence of fasting status. In the absence of ultrasonic guidance, the nerve stimulator still remains a valuable tool in performing a brachial block, but its use is difficult in an emergency surgical patient and greater cautious approach is essential. We identified the supraclavicular plexus by the nerve stimulation-motor response technique as follows. Anterior chest muscles contractions, diaphragmatic contraction, deltoid contractions, and posterior shoulder girdle muscle contractions when identified were taken as “negative response” with decreasing stimulating current. A forearm muscle contraction, especially “wrist flexion” and “finger flexion” at 0.5 mA of current was taken as “positive response.” If no positive response was identified, the “elbow flexion” was considered as the final positive response for successful drug placement. The series of patients had difficulty for administering both general and regional anesthesia and we considered them as complex scenarios. The risk of the block failure was weighed heavily against the benefits of its success. The described series includes patients who had successful outcomes in the end and the techniques, merits, and risks are highlighted. PMID:26417145

  2. Evidence-based guideline for neuropathic pain interventional treatments: Spinal cord stimulation, intravenous infusions, epidural injections and nerve blocks

    PubMed Central

    Mailis, Angela; Taenzer, Paul

    2012-01-01

    BACKGROUND: The Special Interest Group of the Canadian Pain Society has produced consensus-based guidelines for the pharmacological management of neuropathic pain. The society aimed to generate an additional guideline for other forms of neuropathic pain treatments. OBJECTIVE: To develop evidence-based recommendations for neuropathic pain interventional treatments. METHODS: A task force was created and engaged the Institute of Health Economics in Edmonton, Alberta, to survey the literature pertaining to multiple treatments. Sufficient literature existed on four interventions only: spinal cord stimulation; epidural injections; intravenous infusions; and nerve blocks. A comprehensive search was conducted for systematic reviews, randomized controlled trials and evidence-based clinical practice guidelines; a critical review was generated on each topic. A modified United States Preventive Services Task Force tool was used for quality rating and grading of recommendations. RESULTS: Investigators reviewed four studies of spinal cord stimulation, 19 studies of intravenous infusions, 14 studies of epidural injections and 16 studies of nerve blocks that met the inclusion criteria. The task force chairs rated the quality of evidence and graded the recommendations. Feedback was solicited from the members of the task force. CONCLUSION: There is sufficient evidence to support recommendations for some of these interventions for selected neuropathic pain conditions. This evidence is, at best, moderate and is often limited or conflicting. Pain practitioners are encouraged to explore evidence-based treatment options before considering unproven treatments. Full disclosure of risks and benefits of the available options is necessary for shared decision making and informed consent. PMID:22606679

  3. The quaternary lidocaine derivative QX-314 in combination with bupivacaine for long-lasting nerve block: Efficacy, toxicity, and the optimal formulation in rats

    PubMed Central

    Zheng, Qingshan; Yang, Xiaolin; Lv, Rong; Ma, Longxiang; Liu, Jin; Zhu, Tao; Zhang, Wensheng

    2017-01-01

    Objective The quaternary lidocaine derivative (QX-314) in combination with bupivacaine can produce long-lasting nerve blocks in vivo, indicating potential clinical application. The aim of the study was to investigate the efficacy, safety, and the optimal formulation of this combination. Methods QX-314 and bupivacaine at different concentration ratios were injected in the vicinity of the sciatic nerve in rats; bupivacaine and saline served as controls (n = 6~10). Rats were inspected for durations of effective sensory and motor nerve blocks, systemic adverse effects, and histological changes of local tissues. Mathematical models were established to reveal drug-interaction, concentration-effect relationships, and the optimal ratio of QX-314 to bupivacaine. Results 0.2~1.5% QX-314 with 0.03~0.5% bupivacaine produced 5.8~23.8 h of effective nerve block; while 0.5% bupivacaine alone was effective for 4 h. No systemic side effects were observed; local tissue reactions were similar to those caused by 0.5% bupivacaine if QX-314 were used < 1.2%. The weighted modification model was successfully established, which revealed that QX-314 was the main active ingredient while bupivacaine was the synergist. The formulation, 0.9% QX-314 plus 0.5% bupivacaine, resulted in 10.1 ± 0.8 h of effective sensory and motor nerve blocks. Conclusion The combination of QX-314 and bupivacaine facilitated prolonged sciatic nerve block in rats with a satisfactory safety profile, maximizing the duration of nerve block without clinically important systemic and local tissue toxicity. It may emerge as an alternative approach to post-operative pain treatment. PMID:28334014

  4. 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

  5. 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.

  6. Effect of Dexmedetomidine as an Adjuvant to 0.75% Ropivacaine in Interscalene Brachial Plexus Block Using Nerve Stimulator: A Prospective, Randomized Double-blind Study

    PubMed Central

    Rashmi, H. D.; Komala, H. K.

    2017-01-01

    Background: Ropivacaine, a newer local anesthetic (LA), has been increasingly used nowadays in different concentrations for peripheral nerve blocks. It has lesser cardiac toxicity and higher safety margin when compared to bupivacaine. Dexmedetomidine, a novel α2 agonist, is widely used as adjuvant to LA in peripheral nerve blocks to decrease the time of onset and increase the duration of the block. In this study, we evaluated the effect of dexmedetomidine as an adjuvant with 0.75% ropivacaine for interscalene brachial plexus block using nerve stimulator. Aim: This study aims to know the effect of using dexmedetomidine as an adjuvant to 0.75% ropivacaine in interscalene brachial plexuses block using nerve stimulator. Settings and Designs: Sixty patients scheduled for elective orthopedic surgery of the upper limb under interscalene block were considered in this prospective randomized controlled double-blind study. The study population was randomly divided into two groups with thirty patients in each group by using computerized randomization. Materials and Methods: Group R received 30 ml of 0.75% ropivacaine with 0.5 ml normal saline and Group RD received 30 ml of 0.75% ropivacaine with 50 μg of dexmedetomidine. The onset of sensory and motor blocks, duration of sensory and motor block, and patient satisfaction score were observed. Results: Both the groups were comparable in demographic characteristics. The onset of the sensory and motor block is earlier and statistically significant in Group RD (P < 0.05) when compared to Group R. The duration of sensory and motor blockade were significantly prolonged in Group RD (P < 0.0001). Conclusion: Addition of dexmedetomidine to 0.75% ropivacaine in interscalene brachial plexus block significantly shortened the time of onset of the block and prolongs the duration sensory and motor blockade. PMID:28298772

  7. 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.

  8. Technique, Efficiency and Safety of Different Nerve Blocks for Analgesia in Laser Ablation and Sclerotherapy for Lower Limb Superficial Venous Insufficiency – A Multicentre Experience

    PubMed Central

    Joy, Binu; Sandhyala, Abhilash; Naiknaware, Kiran; Ray, Brijesh; Vijayakumar

    2016-01-01

    Introduction Laser ablation and sclerotherapy, as minimally invasive alternatives to surgery for varicose veins, have good efficacy, safety and cosmetic result. Some form of anaesthesia is generally used for pain control. Aim To describe the technique and evaluate the efficacy and safety of femoral, saphenous and sciatic nerve blocks in isolation or in combination for analgesia during laser ablation and sclerotherapy for lower limb varicose veins. Materials and Methods In this prospective observational study, over a period of 33 months, in 856 limbs of 681 patients with varicose veins, ultrasound guided femoral, saphenous and sciatic nerve blocks for analgesia were performed in 769, 808 and 52 instances respectively; following which, endovenous laser ablation, sclerotherapy or combination of both were carried out using standard practice. After completion of the procedure, Visual Analogue Pain Scale (VAS) was used for pain assessment, and muscle weakness was assessed clinically. Results Nerve blocks could be successfully performed in all patients. Observed pain scores were 0 or 1 in 591 (69%), 2 or 3 in 214 (25%) and 4 in 51 (9%) legs with no score more than 4. Higher grades of pain were noted in femoral blocks during early stages of our learning curve. Mild to moderate muscle weakness was observed in 163 (2%) and 7 (13%) patients who underwent femoral and sciatic block respectively, which persisted for an average of two and a half hours and none beyond four and a half hours; saphenous nerve being a pure sensory nerve, did not cause motor weakness. Conclusion For analgesia during laser ablation and/or sclerotherapy of varicose veins, ultrasound guided nerve blocks can be easily and quickly performed. They provide excellent pain relief and comfort to the patient and to the operator; and they do not cause any additional complication. PMID:28050474

  9. Successive motor nerve blocks to identify the muscles causing a spasticity pattern: example of the arm flexion pattern.

    PubMed

    Genet, F; Schnitzler, A; Droz-Bartholet, F; Salga, M; Tatu, L; Debaud, C; Denormandie, P; Parratte, B

    2017-01-01

    Botulinum Toxin A has been the main treatment for spasticity since the beginning of the 1990s. Surprisingly, there is still no consensus regarding injection parameters or, importantly, how to determine which muscles to target to improve specific functions. The aim of this study was to develop a systematic approach to determine this, using the example of the arm flexion pattern. We first determined anatomical landmarks for selective motor block of the brachialis nerve, using 20 forearms from 10 fresh cadavers in Ecole Européenne de Chirurgie and a university-based dissection centre, Paris, France. We then carried out selective blocks of the motor nerves to the brachialis, brachioradialis and biceps brachii in patients with stroke with an arm flexion pattern, in a University Rehabilitation Hospital, Garches, France. We measured: the resting angle of the elbow angle in standing (manual goniometer), active and passive range of extension, and spasticity using the Held and Tardieu and the Modified Ashworth scales. Range of passive elbow extension was also measured with the shoulder in 90° of flexion. The resting angle of the elbow in standing decreased by 35.0° (from 87.6 ± 23.7 to 52.6 ± 24.2°) with inhibition of brachialis, by a further 3.9° (from 52.6 ± 24.2 to 48.7 ± 23.7°) with inhibition of brachioradialis and a further 14.5° (from 48.7 ± 23.7to 34.2 ± 20.7°) with inhibition of biceps brachii. These results were consistent with the clinical evaluation of passive elbow range of motion with the shoulder at 90°. Sequential blocking of the nerves to the three main elbow flexors revealed that the muscle that limited elbow extension the most, was brachialis. This muscle should be the main target to improve the arm flexion pattern. These results show that it is important not simply to inject the most superficial or powerful muscles to treat a spastic deformity. A comprehensive assessment is required. The strategy proposed in this paper should

  10. Articaine for supplemental buccal mandibular infiltration anesthesia in patients with irreversible pulpitis when the inferior alveolar nerve block fails.

    PubMed

    Matthews, Rachel; Drum, Melissa; Reader, Al; Nusstein, John; Beck, Mike

    2009-03-01

    The purpose of this prospective study was to determine the anesthetic efficacy of the supplemental buccal infiltration injection of a cartridge of 4% articaine with 1:100,000 epinephrine in mandibular posterior teeth diagnosed with irreversible pulpitis when the conventional inferior alveolar nerve (IAN) block failed. Fifty-five emergency patients, diagnosed with irreversible pulpitis of a mandibular posterior tooth, received an IAN block and had moderate to severe pain on endodontic access. An infiltration of a cartridge of 4% articaine with 1:100,000 epinephrine was administered buccal to the tooth requiring endodontic treatment. Success of the infiltration injection was defined as no pain or mild pain on endodontic access or instrumentation. The results showed that anesthetic success was obtained in 58% of the mandibular posterior teeth. We can conclude that when the IAN block fails to provide profound pulpal anesthesia, the supplemental buccal infiltration injection of a cartridge of 4% articaine with 1:100,000 epinephrine would be successful 58% of the time for mandibular posterior teeth in patients presenting with irreversible pulpitis. Unfortunately, the modest success rate would not provide predictable pulpal anesthesia for all patients requiring profound anesthesia.

  11. Upper extremity nerve block: how can benefit, duration, and safety be improved? An update

    PubMed Central

    Brattwall, Metha; Jildenstål, Pether; Warrén Stomberg, Margareta; Jakobsson, Jan G.

    2016-01-01

    Upper extremity blocks are useful as both sole anaesthesia and/or a supplement to general anaesthesia and they further provide effective postoperative analgesia, reducing the need for opioid analgesics. There is without doubt a renewed interest among anaesthesiologists in the interscalene, supraclavicular, infraclavicular, and axillary plexus blocks with the increasing use of ultrasound guidance. The ultrasound-guided technique visualising the needle tip and solution injected reduces the risk of side effects, accidental intravascular injection, and possibly also trauma to surrounding tissues. The ultrasound technique has also reduced the volume needed in order to gain effective block. Still, single-shot plexus block, although it produces effective anaesthesia, has a limited duration of postoperative analgesia and a number of adjuncts have been tested in order to prolong analgesia duration. The addition of steroids, midazolam, clonidine, dexmedetomidine, and buprenorphine has been studied, all being off-label when administered by perineural injection, and the potential neurotoxicity needs further study. The use of perineural catheters is an effective option to improve and prolong the postoperative analgesic effect. Upper extremity plexus blocks have an obvious place as a sole anaesthetic technique or as a powerful complement to general anaesthesia, reducing the need for analgesics and hypnotics intraoperatively, and provide effective early postoperative pain relief. Continuous perineural infusion is an effective option to prolong the effects and improve postoperative quality. PMID:27239291

  12. Adding dexmedetomidine to ropivacaine for lumbar plexus and sciatic nerve block for amputation of lower limb in high-risk patient-a case report.

    PubMed

    Wang, Chun-Guang; Ding, Yan-Ling; Han, Ai-Ping; Hu, Chang-Qing; Hao, Shi; Zhang, Fang-Fang; Li, Yong-Wang; Liu, Hu; Han, Zhe; Guo, De-Li; Zhang, Zhi-Qiang

    2015-01-01

    The ischemia necrosis of limb frequently requires surgery of amputation. Lumbar plexus and sciatic nerve block is an ideal intra-operative anesthetic and post-operative antalgic technique for patients of amputation, especially for high-risk patients who have severe cardio-cerebrovascular diseases. However, the duration of analgesia of peripheral nerve block is hardly sufficient to avoid the postoperative pain and the usage of opioids. In this case, a 79-year-old man, with multiple cerebral infarcts, congestive heart failure, atrial flutter and syncope, was treated with an above knee amputation because of ischemia necrosis of his left lower limb. Dexmedetomidine 1 μg/kg was added to 0.33% ropivacaine for lumbar plexus and sciatic nerve block in this case for intra-operative anesthesia and post-operative analgesia. The sensory function was blocked fully for surgery and the duration of analgesia maintained 26 hours with haemodynamic stability and moderate sedation. The patient did not complain pain and require any supplementary analgesics after surgery. This case showed that adding 1 μg/kg dexmedetomidine to ropivacaine for lumbar plexus and sciatic nerve block may be a feasible and safe technique for high-risk patients for lower limb surgery of amputation.

  13. Adding dexmedetomidine to ropivacaine for lumbar plexus and sciatic nerve block for amputation of lower limb in high-risk patient-a case report

    PubMed Central

    Wang, Chun-Guang; Ding, Yan-Ling; Han, Ai-Ping; Hu, Chang-Qing; Hao, Shi; Zhang, Fang-Fang; Li, Yong-Wang; Liu, Hu; Han, Zhe; Guo, De-Li; Zhang, Zhi-Qiang

    2015-01-01

    The ischemia necrosis of limb frequently requires surgery of amputation. Lumbar plexus and sciatic nerve block is an ideal intra-operative anesthetic and post-operative antalgic technique for patients of amputation, especially for high-risk patients who have severe cardio-cerebrovascular diseases. However, the duration of analgesia of peripheral nerve block is hardly sufficient to avoid the postoperative pain and the usage of opioids. In this case, a 79-year-old man, with multiple cerebral infarcts, congestive heart failure, atrial flutter and syncope, was treated with an above knee amputation because of ischemia necrosis of his left lower limb. Dexmedetomidine 1 μg/kg was added to 0.33% ropivacaine for lumbar plexus and sciatic nerve block in this case for intra-operative anesthesia and post-operative analgesia. The sensory function was blocked fully for surgery and the duration of analgesia maintained 26 hours with haemodynamic stability and moderate sedation. The patient did not complain pain and require any supplementary analgesics after surgery. This case showed that adding 1 μg/kg dexmedetomidine to ropivacaine for lumbar plexus and sciatic nerve block may be a feasible and safe technique for high-risk patients for lower limb surgery of amputation. PMID:26550393

  14. Trigeminal nerve block with alcohol for medically intractable classic trigeminal neuralgia: long-term clinical effectiveness on pain

    PubMed Central

    Han, Kyung Ream; Chae, Yun Jeong; Lee, Jung Dong; Kim, Chan

    2017-01-01

    Background: Trigeminal nerve block (Tnb) with alcohol for trigeminal neuralgia (TN) may not be used widely as a percutaneous procedure for medically intractable TN in recent clinical work, because it has been considered having a limited duration of pain relief, a decrease in success rate and increase in complications on repeated blocks. Objectives: To evaluate the clinical outcome of the Tnb with alcohol in the treatment of medically intractable TN. Methods: Six hundred thirty-two patients were diagnosed with TN between March 2000 and February 2010. Four hundred sixty-five out of 632 underwent Tnb with alcohol under a fluoroscope. Pain relief duration were analyzed and compared in the individual branch blocks. Outcomes were compared between patients with and without a previous Tnb with alcohol. Results: Tnb with alcohol were performed in a total 710 (1st-465, 2nd-155, 3rd-55, 4th-23, 5th-8, 6th-4) cases for a series of consecutive 465 patients during the study period. Forty hundred sixty two out of the 465 patients experienced immediate complete pain relief (99%) at the first Tnb. Of the 465 patients, 218 patients (46.9%) did not require any further treatment after the first Tnb with alcohol during an entire study period. One hundred fifty nine (34.2 %) out of the 465 patients experienced recurring pain after the first block, among whom 155 patients received subsequent blocks, and the remaining 4 patients decided to take medication. According to the Kaplan-Meier analysis, the probabilities of remaining pain relief for 1, 2, 3, and 5 years after the procedures were 86.2%, 65.5%, 52.5%, and 33.4%, respectively. There was no significant difference in the probability of pain relief duration between patients with and without previous Tnb with alcohol. Median (95% CI) pain relief durations of the first and repeated blocks were 39 (36-51) and 37 (28-54) months, respectively. There was no significant difference in occurrence of complications between patients with and

  15. Multimodal periarticular injection vs continuous femoral nerve block after total knee arthroplasty: a prospective, crossover, randomized clinical trial.

    PubMed

    Ng, Fu-Yuen; Ng, Jacobus Kwok-Fu; Chiu, Kwong-Yuen; Yan, Chun-Hoi; Chan, Chi-Wing

    2012-06-01

    This study compares the efficacy of pain control using continuous femoral nerve block (FNB) and multimodal periarticular soft tissue injection. This is a randomized, crossover, clinical trial. Sixteen patients having bilateral osteoarthritis of the knee scheduled for staged total knee arthroplasty were randomized to receive either FNB (0.2% ropivacaine), via indwelling catheter for 72 hours, or multimodal periarticular soft tissue injection in the first stage. In the second stage, they received the opposite treatment. The primary outcome measure was morphine consumption by patient-controlled analgesia in the first 72 hours postoperatively. Cumulative morphine consumption as well as rest pain and motion pain in the first 72 hours was comparable between the 2 groups. The functional outcomes did not differ significantly. We conclude that multimodal periarticular soft tissue injection provides comparable analgesia to continuous FNB after total knee arthroplasty.

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

    PubMed

    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.

  17. [Peripheral nerve block. An overview of new developments in an old technique].

    PubMed

    Graf, B M; Martin, E

    2001-05-01

    General anaesthesia and peripheral neuronal blockade are techniques which were introduced into clinical practice at the same time. Although general anaesthesia was accepted significantly faster due to effective new drugs and apparent ease of handling, neuronal blockade has recently gained great importance. The reasons are in particular newer aids such as industrially produced catheter sets, nerve stimulators and ultrasound guidance which have facilitated that these economical techniques can be used not only for intraoperative anaesthesia but also for perioperative analgesia without any major risks for the patients. In parallel to epidural anaesthesia a change of paradigms has recently taken place using catheter instead of single-shot techniques. This allows the loading dose of the local anaesthetics to be installed in a safe way, to reload the dose when intraoperatively required and to extend the analgesia perioperatively by this technique using lower concentrations of the same drugs or drug combinations. A great number of short, middle or long acting local anaesthetics are available to choose the right drug for any particular case. Short and middle acting drugs are characterised by a faster onset compared to long acting drugs, but toxic plasma levels are seen during long time application causing seizures or drowsiness or by using prilocaine methemoglobin. Therefore long acting local anaesthetics such as bupivacaine, ropivacaine or levobupivacaine are the first choice drugs for long time application via peripheral nerve catheters for perioperative anaesthesia and analgesia. By using low concentrations of these potent drugs even for a longer period of time, no toxic plasma levels are seen with the exception of artificial intravasal injections. Additives such as opioids and alpha 2-sympathomimetics are also used. While the use of opioids is controversial, alpha 2-sympathomimetics are able to accelerate the onset and to extend the duration of regional anaesthesia and

  18. 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

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

    PubMed

    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.

  20. 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

  1. A simulation study of the combined thermoelectric extracellular stimulation of the sciatic nerve of the Xenopus laevis: the localized transient heat block.

    PubMed

    Mou, Zongxia; Triantis, Iasonas F; Woods, Virginia M; Toumazou, Christofer; Nikolic, Konstantin

    2012-06-01

    The electrical behavior of the Xenopus laevis nerve fibers was studied when combined electrical (cuff electrodes) and optical (infrared laser, low power sub-5 mW) stimulations are applied. Assuming that the main effect of the laser irradiation on the nerve tissue is the localized temperature increase, this paper analyzes and gives new insights into the function of the combined thermoelectric stimulation on both excitation and blocking of the nerve action potentials (AP). The calculations involve a finite-element model (COMSOL) to represent the electrical properties of the nerve and cuff. Electric-field distribution along the nerve was computed for the given stimulation current profile and imported into a NEURON model, which was built to simulate the electrical behavior of myelinated nerve fiber under extracellular stimulation. The main result of this study of combined thermoelectric stimulation showed that local temperature increase, for the given electric field, can create a transient block of both the generation and propagation of the APs. Some preliminary experimental data in support of this conclusion are also shown.

  2. Potential role of endurance training in altering renal sympathetic nerve activity in CKD?

    PubMed

    Howden, Erin J; Lawley, Justin S; Esler, Murray; Levine, Benjamin D

    2017-05-01

    Chronic kidney disease (CKD), is characterized by a progressive loss of renal function and increase in cardiovascular risk. In this review paper, we discuss the pathophysiology of increased sympathetic nerve activity in CKD patients and raise the possibility of endurance exercise being an effective countermeasure to address this problem. We specifically focus on the potential role of endurance training in altering renal sympathetic nerve activity as increased renal sympathetic nerve activity negatively impacts kidney function as well indirectly effects multiple other systems and organs. Recent technological advances in device based therapy have highlighted the detrimental effect of elevated renal sympathetic nerve activity in CKD patients, with kidney function and blood pressure being improved post renal artery nerve denervation in selected patients. These developments provide optimism for the development of alternative and/or complementary strategies to lower renal sympathetic nerve activity. However, appropriately designed studies are required to confirm preliminary observations, as the widespread use of the renal denervation approach to lower sympathetic activity presently has limited feasibility. Endurance training may be one alternative strategy to reduce renal sympathetic nerve activity. Here we review the role of endurance training as a potential alternative or adjunctive to current therapy in CKD patients. We also provide recommendations for future research to assist in establishing an evidence base for the use of endurance training to lower renal sympathetic activity in CKD patients.

  3. Circadian Rhythm Influences the Promoting Role of Pulsed Electromagnetic Fields on Sciatic Nerve Regeneration in Rats

    PubMed Central

    Zhu, Shu; Ge, Jun; Liu, Zhongyang; Liu, Liang; Jing, Da; Ran, Mingzi; Wang, Meng; Huang, Liangliang; Yang, Yafeng; Huang, Jinghui; Luo, Zhuojing

    2017-01-01

    Circadian rhythm (CR) plays a critical role in the treatment of several diseases. However, the role of CR in the treatment of peripheral nerve defects has not been studied. It is also known that the pulsed electromagnetic fields (PEMF) can provide a beneficial microenvironment to quicken the process of nerve regeneration and to enhance the quality of reconstruction. In this study, we evaluate the impact of CR on the promoting effect of PEMF on peripheral nerve regeneration in rats. We used the self-made “collagen-chitosan” nerve conduits to bridge the 15-mm nerve gaps in Sprague-Dawley rats. Our results show that PEMF stimulation at daytime (DPEMF) has most effective outcome on nerve regeneration and rats with DPEMF treatment achieve quickly functional recovery after 12 weeks. These findings indicate that CR is an important factor that determines the promoting effect of PEMF on peripheral nerve regeneration. PEMF exposure in the daytime enhances the functional recovery of rats. Our study provides a helpful guideline for the effective use of PEMF mediations experimentally and clinically. PMID:28360885

  4. 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

  5. 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

  6. 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

  7. Role of the vagus nerve in the development and treatment of diet-induced obesity.

    PubMed

    de Lartigue, Guillaume

    2016-10-15

    This review highlights evidence for a role of the vagus nerve in the development of obesity and how targeting the vagus nerve with neuromodulation or pharmacology can be used as a therapeutic treatment of obesity. The vagus nerve innervating the gut plays an important role in controlling metabolism. It communicates peripheral information about the volume and type of nutrients between the gut and the brain. Depending on the nutritional status, vagal afferent neurons express two different neurochemical phenotypes that can inhibit or stimulate food intake. Chronic ingestion of calorie-rich diets reduces sensitivity of vagal afferent neurons to peripheral signals and their constitutive expression of orexigenic receptors and neuropeptides. This disruption of vagal afferent signalling is sufficient to drive hyperphagia and obesity. Furthermore neuromodulation of the vagus nerve can be used in the treatment of obesity. Although the mechanisms are poorly understood, vagal nerve stimulation prevents weight gain in response to a high-fat diet. In small clinical studies, in patients with depression or epilepsy, vagal nerve stimulation has been demonstrated to promote weight loss. Vagal blockade, which inhibits the vagus nerve, results in significant weight loss. Vagal blockade is proposed to inhibit aberrant orexigenic signals arising in obesity as a putative mechanism of vagal blockade-induced weight loss. Approaches and molecular targets to develop future pharmacotherapy targeted to the vagus nerve for the treatment of obesity are proposed. In conclusion there is strong evidence that the vagus nerve is involved in the development of obesity and it is proving to be an attractive target for the treatment of obesity.

  8. Role of dorsal root ganglion K2P1.1 in peripheral nerve injury-induced neuropathic pain

    PubMed Central

    Mao, Qingxiang; Yuan, Jingjing; Xiong, Ming; Wu, Shaogen; Chen, Liyong; Bekker, Alex; Yang, Tiande

    2017-01-01

    Peripheral nerve injury-caused hyperexcitability and abnormal ectopic discharges in the primary sensory neurons of dorsal root ganglion (DRG) play a key role in neuropathic pain development and maintenance. The two-pore domain background potassium (K2P) channels have been identified as key determinants of the resting membrane potential and neuronal excitability. However, whether K2P channels contribute to neuropathic pain is still elusive. We reported here that K2P1.1, the first identified mammalian K2P channel, was highly expressed in mouse DRG and distributed in small-, medium-, and large-sized DRG neurons. Unilateral lumbar (L) 4 spinal nerve ligation led to a significant and time-dependent reduction of K2P1.1 mRNA and protein in the ipsilateral L4 DRG, but not in the contralateral L4 or ipsilateral L3 DRG. Rescuing this reduction through microinjection of adeno-associated virus-DJ expressing full-length K2P1.1 mRNA into the ipsilateral L4 DRG blocked spinal nerve ligation-induced mechanical, thermal, and cold pain hypersensitivities during the development and maintenance periods. This DRG viral microinjection did not affect acute pain and locomotor function. Our findings suggest that K2P1.1 participates in neuropathic pain development and maintenance and may be a potential target in the management of this disorder. PMID:28326939

  9. Anatomy of greater palatine foramen and canal and pterygopalatine fossa in Thais: considerations for maxillary nerve block.

    PubMed

    Methathrathip, D; Apinhasmit, W; Chompoopong, S; Lertsirithong, A; Ariyawatkul, T; Sangvichien, S

    2005-12-01

    This study aims to investigate the anatomy of the greater palatine foramen (GPF), greater palatine canal (GPC) and pterygopalatine fossa (PPF) with special reference to the blockage of the maxillary nerve. A correlation between the length of GPC and PPF and the heights of the orbit and the maxilla was also studied using simple linear regression analysis. The morphology of the GPF, GPC and PPF as well as heights of the orbit and the maxilla were assessed in 105 Thai skulls. The thickness of the mucosa over the GPF was also measured from the dissection of 55 cadavers. The results showed that most GPF appeared as an oval foramen located at the palatal aspect of the upper third molar. The GPF was 16.2+/-1.3 mm lateral to the median sagittal plane of the hard palate, 2.1+/-1.3 mm anterior to the posterior border of the hard palate and 5.1+/-1.3 mm from the greatest concavity of the distolateral margin of the hard palate. The mean length of GPC and PPF was 29.7+/-4.2 mm. The mean angles of the GPC in relation to the hard palate and the vertical plane were 57.9+/-5.8 degrees and 6.7+/-5.2 degrees , respectively. In attempting to insert a needle to reach the foramen rotundum through the GPF, 31.7% passed into the orbit while 8.7% passed into the brain. The mean thickness of the mucosa over GPF was 6.7+/-2.3 mm. Two models for estimating the depth of needle injection in maxillary nerve block have been developed as follows: Length of GPC and PPF=19.038+0.314 (orbital height) and length of GPC and PPF=21.204+0.187 (maxillary height). The calculated length combined with the mucosal thickness was the estimated depth of needle injection. In conclusion, our results concerning the GPF, GPC and PPF will provide the useful reference for clinicians to anesthetize the maxillary nerve with a greater degree of success.

  10. 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

  11. Perineural Administration of Dexmedetomidine in Combination with Bupivacaine Enhances Sensory and Motor Blockade in Sciatic Nerve Block without Inducing Neurotoxicity in the Rat

    PubMed Central

    Brummett, Chad M.; Norat, Mary A.; Palmisano, John M.; Lydic, Ralph

    2008-01-01

    Background The present study was designed to test the hypothesis that high-dose dexmedetomidine added to local anesthetic would increase the duration of sensory and motor blockade in a rat model of sciatic nerve blockade without causing nerve damage. Methods Thirty-one adult Sprague Dawley rats received bilateral sciatic nerve blocks with either 0.2 ml of 0.5% bupivacaine and 0.5% bupivacaine plus 0.005% dexmedetomidine in the contralateral leg, or 0.2 ml of 0.005% dexmedetomidine and normal saline in the contralateral leg. Sensory and motor function were assessed by a blinded investigator every 30 minutes until the return of normal sensory and motor function. Sciatic nerves were harvested at either 24 hours or 14 days after injection and analyzed for perineural inflammation and nerve damage. Results High-dose dexmedetomidine added to bupivacaine significantly enhanced the duration of sensory and motor blockade. Dexmedetomidine alone did not cause significant motor or sensory block. All of the nerves analyzed had normal axons and myelin at 24 hours and 14 days. Bupivacaine plus dexmedetomidine showed less perineural inflammation at 24 hours than the bupivacaine group when compared with the saline control. Conclusion The finding that high-dose dexmedetomidine can safely improve the duration of bupivacaine-induced antinociception following sciatic nerve blockade in rats is an essential first step encouraging future studies in humans. The dose of dexmedetomidine used in this study may exceed the sedative safety threshold in humans and could cause prolonged motor blockade, therefore future work with clinically relevant doses is necessary. PMID:18719449

  12. Overlooked physical diagnoses in chronic pain patients involved in litigation, Part 2. The addition of MRI, nerve blocks, 3-D CT, and qualitative flow meter.

    PubMed

    Hendler, N; Bergson, C; Morrison, C

    1996-01-01

    This study followed 120 chronic pain patients referred to a multidisciplinary pain center. The referral diagnosis for many patients, such as "chronic pain," "psychogenic pain," or "lumbar strain," was frequently found to be incomplete or inaccurate (40%) following a multidisciplinary evaluation that used appropriate diagnostic studies, including magnetic resonance imaging, computed tomography, nerve blocks, and qualitative flowmeter. Significant abnormalities were discovered in 76% of the diagnostic tests. An organic origin for pain was found in 98% of these patients. The patients were discharged with objective verification of diagnoses including facet disease, nerve entrapment, temporomandibular joint disease, thoracic outlet syndrome, and herniated discs.

  13. Structural evidence that botulinum toxin blocks neuromuscular transmission by impairing the calcium influx that normally accompanies nerve depolarization

    PubMed Central

    1981-01-01

    Taking advantage of the fact that nerve terminal mitochondria swell and sequester calcium during repetitive nerve stimulation, we here confirm that this change is caused by calcium influx into the nerve and use this fact to show that botulinum toxin abolishes such calcium influx. The optimal paradigm for producing the mitochondrial changes in normal nerves worked out to be 5 min of stimulation at 25 Hz in frog Ringer's solution containing five time more calcium than normal. Applying this same stimulation paradigm to botulinum-intoxicated nerves produced no mitochondrial changes at all. Only when intoxicated nerves were stimulated in 4-aminopyridine (which grossly exaggerates calcium currents in normal nerves) or when they were soaked in black widow spider venom (which is a nerve-specific calcium ionophore) could nerve mitochondria be induced to swell and accumulate calcium. These results indicate that nerve mitochondria are not damaged directly by the toxin and point instead to a primary inhibition of the normal depolarization- evoked calcium currents that accompany nerve activity. Because these currents normally provide the calcium that triggers transmitter secretion from the nerve, this demonstration of their inhibition helps to explain how botulinum toxin paralyzes. PMID:6259176

  14. 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.

  15. 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

  16. Combination Therapy with Continuous Three-in-One Femoral Nerve Block and Periarticular Multimodal Drug Infiltration after Total Hip Arthroplasty

    PubMed Central

    Tetsunaga, Tomoko; Fujiwara, Kazuo; Endo, Hirosuke; Ozaki, Toshifumi

    2016-01-01

    Background. Various postoperative pain relief modalities, including continuous femoral nerve block (CFNB), local infiltration analgesia (LIA), and combination therapy, have been reported for total knee arthroplasty. However, no studies have compared CFNB with LIA for total hip arthroplasty (THA). The aim of this study was to compare the efficacy of CFNB versus LIA after THA. Methods. We retrospectively reviewed the postoperative outcomes of 93 THA patients (20 men, 73 women; mean age 69.2 years). Patients were divided into three groups according to postoperative analgesic technique: CFNB, LIA, or combined CFNB+LIA. We measured the following postoperative outcome parameters: visual analog scale (VAS) for pain at rest, supplemental analgesia, side effects, mobilization, length of hospital stay, and Harris Hip Score (HHS). Results. The CFNB+LIA group had significantly lower VAS pain scores than the CFNB and LIA groups on postoperative day 1. There were no significant differences among the three groups in use of supplemental analgesia, side effects, mobilization, length of hospital stay, or HHS at 3 months after THA. Conclusions. Although there were no clinically significant differences in outcomes among the three groups, combination therapy with CFNB and LIA provided better pain relief after THA than CFNB or LIA alone, with few side effects. PMID:28070159

  17. Anesthetic efficacy of articaine for inferior alveolar nerve blocks in patients with symptomatic versus asymptomatic irreversible pulpitis.

    PubMed

    Argueta-Figueroa, Liliana; Arzate-Sosa, Gabriel; Mendieta-Zeron, Hugo

    2012-01-01

    This study sought to determine the anesthetic efficacy of 4% articaine with 1:100,000 epinephrine in patients with symptomatic and asymptomatic irreversible pulpitis in mandibular posterior teeth and if individual patient factors, pulpal disease characteristics, and previous medication are correlated to local anesthetic success. A second objective was to determine the specificity and sensibility of a cold test for prediction of anesthetic success prior to endodontic treatment. Seventy patients diagnosed with irreversible pulpitis in mandibular posterior teeth received 1.6 mL of 4% articaine with 1:100,000 epinephrine for an inferior alveolar nerve block (IANB) using a metal guide. The anesthetic solution was injected with a computer-preprogrammed delivery system for local anesthesia. Endodontic access was begun 15 minutes after solution deposition; later, patients rated their discomfort using the visual analog scale (VAS). The success rate for the IA NB using articaine was 64.2% in patients with symptomatic irreversible pulpitis and 86.9% in patients with asymptomatic irreversible pulpitis. Cold test prior to root canal treatment had a specificity and sensibility of 12.5% and 87.1%, respectively. The anesthetic efficacy of articaine in irreversible pulpitis is moderately acceptable, and anesthetic success increases when the patient has been premedicated with NSAIDs. The cold test appears to be a favorable indicator for predicting anesthetic success.

  18. 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

  19. 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.

  20. Role of renal nerves on renal functional change after back heating in the rat.

    PubMed

    Chen, C F; Chien, C T; Wu, M S; Fu, T C

    1994-06-20

    This study was designed to investigate the possible role of renal nerves in the regulation of renal function after the application of heat (BH), by means of an electric heating pad (42 +/- 1 degree C) to the skin of the back overlying the kidneys. Both renal efferent (RENA) and renal afferent nervous activity (RANA) were recorded in 7 anesthetized female Wistar rats. It was found that RENA reduced to less than 80% of the control level during 30 min of back heating, accompanied by an increase in excretion of urine, sodium and potassium, and enhanced the glomerular filtration rate. BH in 9 chronic bilateral renal denervated rats (RD) showed the same renal responses as in the renal nerve intact rats (RI) after back heating. It is concluded that renal nerves played only a partially role in the renal diuretic action of back heating.

  1. Evolution of the transversus abdominis plane block and its role in postoperative analgesia.

    PubMed

    Lissauer, Jonathan; Mancuso, Kenneth; Merritt, Christopher; Prabhakar, Amit; Kaye, Alan David; Urman, Richard D

    2014-06-01

    Since it was first described by Rafi in 2001, the transversus abdominis plane (TAP) block can be best described as a peripheral nerve block to the anterior abdominal wall (T6 to L1). The TAP block is specifically a local anesthetic injection into the fascial plane superficial to the transversus abdominis muscle and deep to the internal oblique muscle. The TAP block has been a subject of controversy with regard to utility, to indications, and more fundamentally, how best to place the block and its precise mechanism of action. The evolution of thinking with regard to this block, or more correctly family of interrelated blocks, includes knowledge of underlying anatomy, as well as an appreciation of its varied approaches. The TAP block affords excellent analgesia for abdominal procedures. In summary, the TAP block affords effective analgesia with opioid sparing effects, technical simplicity, and long duration of action. Some disadvantages include the need for bilateral block for midline incisions and absence of effectiveness for visceral pain.

  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. THE ROLE OF MACROPHAGES IN OPTIC NERVE REGENERATION

    PubMed Central

    CUI, Q.; YIN, Y.; BENOWITZ, L. I.

    2009-01-01

    Following injury to the nervous system, the activation of macrophages, microglia, and T-cells profoundly affects the ability of neurons to survive and to regenerate damaged axons. The primary visual pathway provides a well-defined model system for investigating the interactions between the immune system and the nervous system after neural injury. Following damage to the optic nerve in mice and rats, retinal ganglion cells, the projection neurons of the eye, normally fail to regenerate their axons and soon begin to die. Induction of an inflammatory response in the vitreous strongly enhances the survival of retinal ganglion cells and enables these cells to regenerate lengthy axons beyond the injury site. T cells modulate this response, whereas microglia are thought to contribute to the loss of retinal ganglion cells in this model and in certain ocular diseases. This review discusses the complex and sometimes paradoxical actions of blood-borne macrophages, resident microglia, and T-cells in determining the outcome of injury in the primary visual pathway. PMID:18708126

  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. 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.

  6. [The inflammatory reflex: the role of the vagus nerve in regulation of immune functions].

    PubMed

    Mravec, B

    2011-01-01

    Experimental studies published in past years have shown an important role of the vagus nerve in regulating immune functions. Afferent pathways of this cranial nerve transmit signals related to tissue damage and immune reactions to the brain stem. After central processing of these signals, activated efferent vagal pathways modulate inflammatory reactions through inhibiting the synthesis and secretion of pro-inflammatory cytokines by immune cells. Therefore, pathways localized in the vagus nerve constitute the afferent and efferent arms of the so-called "inflammatory reflex" that participates in negative feedback regulation of inflammation in peripheral tissues. Activation of efferent pathways of the vagus nerve significantly reduces tissue damage in several models of diseases in experimental animals. Clinical studies also indicate the importance of the vagus nerve in regulating inflammatory reactions in humans. It is suggested that alteration of the inflammatory reflex underlies the etiopathogenesis of diseases characterized by exaggerated production of pro-inflammatory mediators. Therefore, research into the inflammatory reflex may create the basis for developing new approaches in the treatment of diseases with inflammatory components.

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

    DTIC Science & Technology

    2014-12-01

    96, 2013. Hsu, C.C., R.L. Lin, L.-Y. Lee and Y.S. Lin. Hydrogen sulfide induces hypersensitivity of rat lung vagal neurons: role of TRPA1 receptors...or in part by this TATRC project are included in this Annual Progress Report below: 1. Hsu CC, Lin RL, Lee LY, Lin YS. Hydrogen sulfide induces

  8. Combination of general anesthesia and peripheral nerve block with low-dose ropivacaine reduces postoperative pain for several days after outpatient arthroscopy

    PubMed Central

    Büttner, Benedikt; Mansur, Ashham; Hinz, José; Erlenwein, Joachim; Bauer, Martin; Bergmann, Ingo

    2017-01-01

    Abstract Background: Effective methods for postoperative pain relief are an important concern in outpatient surgery. For arthroscopies we combine a single-shot peripheral nerve block using low-volume, low-concentration ropivacaine with general anesthesia. We hypothesized that the patients would have less postoperative pain and be more rapidly home ready than after general anesthesia alone. Methods: Patients (American Society of Anesthesiologists I–III, 18–80 years old) scheduled for outpatient arthroscopy on the upper or lower extremity were randomized to have either a combination of peripheral nerve block and general anesthesia (NB + GA, study group) or general anesthesia alone (GA, control group). The relevant nerve was localized by ultrasound and 10 mL ropivacaine 0.2% was injected. General anesthesia was with propofol and remifentanil. Numeric rating scales were used to assess pain and patient satisfaction in the recovery room, on the evening of surgery, and on the following 2 days. Results: A total of 120 patients participated in the study (NB + GA: 61; GA: 59). The percentage of patients reporting relevant pain in the recovery room were 0% versus 44% (P < 0.001), on the evening after surgery 3% versus 80% (P < 0.001), and on days 1 and 2 postsurgery 12% versus 73% and 12% versus 64% (NB + GA vs GA, respectively). Median time to home discharge was NB + GA 34.5 min (range 15–90) versus GA 55 min (20–115) (P < 0.001). Conclusions: The combination of a peripheral nerve block with low-dose ropivacaine and general anesthesia reduced postoperative pain compared with general anesthesia alone for several days after outpatient arthroscopy. It also shortened the time to home discharge. PMID:28178149

  9. Role of sensory nerves in gastroprotective effect of anandamide in rats.

    PubMed

    Warzecha, Z; Dembinski, A; Ceranowicz, P; Dembinski, M; Cieszkowski, J; Kownacki, P; Konturek, P C

    2011-04-01

    Previous studies have shown that stimulation of cannabinoid 1 (CB1) receptor protects the gastric mucosa against stress-induced lesion. Aim of the present study was to examine the influence of anandamide on lipid peroxidation and antioxidant defense system in gastric mucosa and the role of sensory nerves in gastroprotective effects of cannabinoids. Studies were performed on rats with intact or ablated sensory nerves (by neurotoxic doses of capsaicin). Gastric lesions were induced by water immersion and restrain stress (WRS). Anandamide was administered at the dose of 0.3, 1.5 or 3.0 μmol/kg, 30 min before exposure to WRS. CB1 receptor antagonist, AM251 (4.0 μmol/kg) was administered 40 min before WRS. WRS induced gastric lesions associated with the decrease in gastric blood flow, mucosal DNA synthesis and mucosal activity of superoxide dismutase (SOD). Serum level of interleukin-1β (IL-1β) and mucosal level of malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) were increased. Administration of anandamide reduced the ulcers area, generation of MDA+4-HNE and serum level of IL-1β, and this effect was associated with the reduction in the WRS-induced decrease in gastric mucosal blood flow, mucosal DNA synthesis and SOD activity. Ablation of sensory nerves increased the area of ulcers, serum level of IL-1β and mucosal content of MDA+4-HNE, whereas mucosal DNA synthesis, SOD activity and blood flow were additionally decreased. In rats with ablation of sensory nerves, administration of anandamide at the high doses (1.5 and 3.0 μmol/kg) partly reduced deleterious effect of WRS on gastric mucosa, but this effect was weaker than in animals with intact sensory nerves. Low dose of anandamide (0.3 μmol/kg) was ineffective in the protection of gastric mucosa against the WRS-induced lesions in rats with ablation of sensory nerves. In rats with intact sensory nerves and exposed to WRS, administration of AM251 exhibited deleterious effect. In rats with ablation of sensory

  10. 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

  11. Development of a glial network in the olfactory nerve: role of calcium and neuronal activity.

    PubMed

    Koussa, Mounir A; Tolbert, Leslie P; Oland, Lynne A

    2010-11-01

    In adult olfactory nerves of mammals and moths, a network of glial cells ensheathes small bundles of olfactory receptor axons. In the developing antennal nerve (AN) of the moth Manduca sexta, the axons of olfactory receptor neurons (ORNs) migrate from the olfactory sensory epithelium toward the antennal lobe. Here we explore developmental interactions between ORN axons and AN glial cells. During early stages in AN glial-cell migration, glial cells are highly dye coupled, dividing glia are readily found in the nerve and AN glial cells label strongly for glutamine synthetase. By the end of this period, dye-coupling is rare, glial proliferation has ceased, glutamine synthetase labeling is absent, and glial processes have begun to extend to enwrap bundles of axons, a process that continues throughout the remainder of metamorphic development. Whole-cell and perforated-patch recordings in vivo from AN glia at different stages of network formation revealed two potassium currents and an R-like calcium current. Chronic in vivo exposure to the R-type channel blocker SNX-482 halted or greatly reduced AN glial migration. Chronically blocking spontaneous Na-dependent activity by injection of tetrodotoxin reduced the glial calcium current implicating an activity-dependent interaction between ORNs and glial cells in the development of glial calcium currents.

  12. Comparison of periarticular anesthesia with liposomal bupivacaine with femoral nerve block for pain control after total knee arthroplasty

    PubMed Central

    Liu, Shu-qun; Chen, Xiang; Yu, Chen-chen; Weng, Cheng-wei; Wu, Yan-qin; Xiong, Jun-cheng; Xu, Shi-hao

    2017-01-01

    Abstract Background: Periarticular anesthesia (PAI) with liposomal bupivacaine (LB) and femoral nerve block (FNB) were 2 common type of pain management after total knee arthroplasty (TKA). There is no consensus about PAI with LB shows better clinical outcome than FNB. Thus, we performed a systematic review and meta-analysis to compare the efficacy and safety of PAI with LB and FNB for patients prepared for TKA. Methods: Randomized controlled trials (RCTs) and non-RCTs from PubMed (1966-2017.2), EMBASE (1980-2017.2), and the Cochrane Central Register of Controlled Trials (CENTRAL, 2017.2), Web of Science (1966-2017.2), and Chinese Wanfang database (1980-2017.2) were searched. Continuous outcomes including visual analogue scale (VAS) at 24, 48, and 72 hours, total morphine consumption, length of hospital, and range of motion (ROM) were reported as the weighted mean difference with 95% and confidence interval (CI) and discontinuous outcomes (the occurrence of postoperative nausea and vomiting [PONV]) were presented as relative risk with 95% CI. Random-effects model was adopted to analyze the relevant data. Results: According to the inclusion and exclusion criteria, 8 studies with 2407 patients were eligible and finally included in this meta-analysis (LB = 1114, FNB = 1293). There was no significant difference between VAS at 24, 4, and 72 hours, ROM, and the occurrence of PONV between PAI with LB group versus FNB group (P > 0.05). Compared with the FNB group, PAI with LB was associated with a significant decrease in length of hospital stay by 0.43 day (MD = −0.43; 95% CI −0.60 to −0.27; P = 0.001) and the total dose of total morphine consumption by (MD = −29.32; 95% CI −57.55 to −1.09; P = 0.042). Conclusions: The review of trials found that PAI with LB provided a significant beneficial effect over FNB in improving the pain or decreased the total morphine consumption in patients who underwent TKA. However, PAI with LB

  13. The Minimum Effective Dose of Lidocaine Needed to Block Evoked Potentials in the Sciatic Nerve of the Rat

    DTIC Science & Technology

    1998-10-01

    a higher concentration of sodium (Na+) ions extracellularly. This, along with the semi-permeable cell membrane, creates a resting membrane potential... sodium ions through voltage gated sodium channels located in the cellular membrane of a nerve (Stoelting, 1991). The anesthetics attach to a specific...receptor on the voltage gated sodium channels that respond to nerve impulses. Blockage of this flow of sodium ions will stop the membrane from

  14. 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.

  15. 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

  16. Intermuscular pterygoid-temporal abscess following inferior alveolar nerve block anesthesia–A computer tomography based navigated surgical intervention: Case report and review

    PubMed Central

    Wallner, Jürgen; Reinbacher, Knut Ernst; Pau, Mauro; Feichtinger, Matthias

    2014-01-01

    Inferior alveolar nerve block (IANB) anesthesia is a common local anesthetic procedure. Although IANB anesthesia is known for its safety, complications can still occur. Today immediately or delayed occurring disorders following IANB anesthesia and their treatment are well-recognized. We present a case of a patient who developed a symptomatic abscess in the pterygoid region as a result of several inferior alveolar nerve injections. Clinical symptoms included diffuse pain, reduced mouth opening and jaw's hypomobility and were persistent under a first step conservative treatment. Since image-based navigated interventions have gained in importance and are used for various procedures a navigated surgical intervention was initiated as a second step therapy. Thus precise, atraumatic surgical intervention was performed by an optical tracking system in a difficult anatomical region. A symptomatic abscess was treated by a computed tomography-based navigated surgical intervention at our department. Advantages and disadvantages of this treatment strategy are evaluated. PMID:24987612

  17. 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

  18. The Comparison of Local Infiltration Analgesia with Peripheral Nerve Block following Total Knee Arthroplasty (TKA): A Systematic Review with Meta-Analysis.

    PubMed

    Fan, Lin; Zhu, Chunyan; Zan, Pengfei; Yu, Xiao; Liu, Jin; Sun, Qi; Li, Guodong

    2015-09-01

    Total knee arthroplasty (TKA) is usually associated with severe post-operative pain, which can prevent rehabilitation of patients' knee function and influence the satisfaction of surgery. Local infiltration analgesia (LIA) is a method that has been applied in clinical practice recently. However, the clinical use of this method is still under discussion. In this paper, we systematically reviewed randomized clinical trails (RCTs) comparing LIA with peripheral nerve block (PNB) to verify the efficacy and safety of LIA. During the analysis, we strictly filtered papers and chose ones that had fewer disturbance variables. We also analyzed the heterogeneity. We conclude that when compared with PNB, pain control with LIA is at least comparable.

  19. 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.

  20. Anaesthetic Efficacy of 4% Articaine Mandibular Buccal Infiltration Compared To 2% Lignocaine Inferior Alveolar Nerve Block in Children with Irreversible Pulpitis

    PubMed Central

    P, Mytri

    2015-01-01

    Background Lidocaine is the gold standard anaesthetic solution that has been used since its inception into dentistry till date. Around 80% of failures have been reported when lignocaine has been used for inferior alveolar nerve block in children and adults with irreversible pulpitis. There is a need to use newer drugs which are available which have been reported to be effective like lignocaine, such as articaine. Although articaine has been used in adults, literature supporting its use in children is sparse. Aim The purpose of this study is to compare the anaesthetic efficacy of 4% articaine buccal infiltration and 2% lignocaine inferior alveolar nerve block in children with irreversible pulpitis. It also aims to assess the need for supplemental intrapulpal injections. Materials and Methods This study was designed as a randomized double-blind cross over trial comparing the anaesthetic effectiveness of 4% articaine with 1:100,000 epinephrine in buccal infiltration and 2% lignocaine IAN block anaesthesia. The study subject and the pediatric dentist performing the pulpectomy procedures were blinded to the study. A sample size of 40 subjects in the age group of 5-8 y was included in the study. Results The onset of anaesthesia with 4% articaine was faster as compared to 2% lignocaine. The duration of anaesthesia with articaine infiltration was shorter. The need for supplemental injection in the articaine group was less. Conclusion Four percent articaine infiltration can be used in children with irreversible pulpitis. It can be used to replace the IAN block in children thereby reducing the post anaesthetic complications like lip biting. PMID:26023647

  1. Selective inhibition of extracellular signal-regulated kinases 1/2 blocks nerve growth factor to brain-derived neurotrophic factor signaling and suppresses the development of and reverses already established pain behavior in rats.

    PubMed

    Matsuoka, Y; Yang, J

    2012-03-29

    Brain-derived neurotrophic factor (BDNF) plays a key role in the development of pathological pain. Although it is known that nerve growth factor (NGF) induces BDNF mRNA through extracellular signal-regulated kinases (ERK), whether ERK1/2 or ERK5, two closely related members of the ERK family, mediate this signal is still unclear because classical MEK inhibitors block both pathways. We studied the involvement of ERK-signaling in NGF induction of BDNF in PC12 cells, cultured dorsal root ganglia neurons, and in rats subjected to neuropathic pain models using ERK1/2- and ERK5-specific tools. Selective activation of ERK1/2 upregulated BDNF mRNA in PC12 cells, whereas selective ERK5 activation did not. AZD6244, a potent selective inhibitor of ERK1/2 activation, blocked NGF induction of BDNF mRNA in vitro suggesting that NGF induction of BDNF is mediated by ERK1/2. siRNA experiments indicated that both ERK1 or ERK2 can signal suggesting that both pathways must be blocked to prevent NGF-induced increase in BDNF mRNA. I.p. injection of AZD6244 prevented the development of pain in rats subjected to the chronic constriction injury and reversed already established pain in the spared nerve injury model. Immunohistochemical studies showed decreased phospho-ERK1/2-immunoreactivity in dorsal root ganglia and BDNF immunoreactivity in ipsilateral spinal dorsal horn in the drug-treated rats. Our results suggest the possible use of AZD6244, already in human clinical trials as an anticancer agent, for the treatment of pathological pain.

  2. 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

  3. Toxicity induced by cumene hydroperoxide in leech Retzius nerve cells: the protective role of glutathione.

    PubMed

    Jovanovic, Zorica; Jovanovic, Svetlana

    2013-01-01

    In the present study, we studied the ability of glutathione (GSH) to detoxify exogenously applied cumene hydroperoxide (CHP). Exposure of leech Retzius nerve cells to CHP (1.5 mM) induced a marked prolongation of the spontaneous spike potential of these cells. Early after depolarization, and a cardiac-like action potential with a rapid depolarization followed by a sustained depolarization or plateau, which is terminated by a rapid repolarization were recorded. GSH (0.2 mM) significantly inhibited the effects of CHP on the duration of the action potential and suppressed CHP-induced spontaneous repetitive activity. Voltage-clamp recordings showed that CHP (1.5 mM) caused significant changes in the outward potassium currents. The fast and slow steady part of the potassium outward current was reduced by 46% and 39%, respectively. GSH applied in a concentration of 0.2 mM partially blocked the effect of CHP on the calcium-activated potassium currents. The fast and slow calcium-activated potassium currents were suppressed by about 20% and 15%, respectively. These results suggest that the neurotoxic effect of CHP on spontaneous spike electrogenesis and calcium-activated potassium currents of leech Retzius nerve cells was reduced in the presence of GSH.

  4. 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

  5. Role of the trigeminal nerve in regrowth of hypoglossal motoneurons after hypoglossal-facial anastomosis.

    PubMed

    Mameli, Ombretta; Pellitteri, Rosalia; Russo, Antonella; Stanzani, Stefania; Caria, Marcello Alessandro; De Riu, Pier Luigi

    2006-12-01

    Conclusion. Functional recovery of facial muscles following hypoglossal-facial anastomosis (HFA) may be dependent not only on sensory information, relayed via the trigeminal nuclei to the hypoglossal nucleus, but also on extratrigeminal fibers, originating from the hypoglossal nucleus that travel in the infraorbital nerve (ION). This fact helps to explain the ability of hypoglossal neurons, after HFA, to induce contractions of muscles originally innervated from other nervous structures. Objective. The aim of the study was to better understand the role of the trigeminal nerve in reinnervation of facial muscles by hypoglossal motoneurons following HFA. Materials and methods. Central afferences of the ION were analyzed in rats by labeling the exposed nerve with horseradish peroxidase (HRP), whereas central organization of the efferent projections to the vibrissal area was analyzed by labeling the whisker pad muscles of the rat with a 5% solution of 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (Dil) in N,N-dimethylformamide. Results. The results show that extratrigeminal fibers, originating in the hypoglossal nucleus, travel along the ION. Retrograde tracing applied to ION or injected into the whisker pad showed labeled neurons in the Pr5 nucleus and all Sp5 trigeminal subnuclei. Small labeled neurons (10-15 microm diameter; 10-12 neurons per section), were also found in the hypoglossal nucleus.

  6. 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.

  7. 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

  8. Ultrasound-Guided Intercostobrachial Nerve Block for Intercostobrachial Neuralgia in Breast Cancer Patients: A Case Series.

    PubMed

    Wisotzky, Eric M; Saini, Vikramjeet; Kao, Cyrus

    2016-03-01

    This case series describes 3 cases in which ultrasound-guided intercostobrachial perineural injection was used for intercostobrachial neuralgia, a common cause of postmastectomy pain syndrome. All cases had undergone modified radical mastectomy with axillary lymph node dissection for breast cancer. Two cases developed axillary and unilateral chest wall pain. The third case initially presented with axillary pain and lateral shoulder pain 1 year out from radical mastectomy. After a cervical epidural steroid injection, her lateral shoulder pain resolved, but she continued to have residual chest wall paresthesia. It was at this time, we decided to treat with an intercostobrachial nerve perineural injection. Injury to the intercostobrachial nerve is thought to be a common cause of postmastectomy pain. In our case series, all patients had pain relief after the intercostobrachial perineural injection. There is a relative dearth of published information on the treatment of postmastectomy pain and more specifically intercostobrachial neuralgia. We review the anatomy of the intercostobrachial nerve and its variants, etiologies of intercostobrachial neuralgia, and current indications and methods of an intercostobrachial perineural injection.

  9. 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

  10. Surface affinity role in graphoepitaxy of lamellar block copolymers

    NASA Astrophysics Data System (ADS)

    Claveau, Guillaume; Quemere, Patrick; Argoud, Maxime; Hazart, Jerome; Barros, Patricia Pimenta; Sarrazin, Aurelien; Posseme, Nicolas; Tiron, Raluca; Chevalier, Xavier; Nicolet, Celia; Navarro, Christophe

    2016-07-01

    Overcoming the optical limitations of 193-nm immersion lithography can be achieved using directed self-assembly (DSA) of block-copolymers (BCPs) as a low-cost and versatile complementary technique. The goal of this paper is to investigate the potential of DSA to address line and space (L/S) high-resolution patterning by performing the density multiplication of lines with the graphoepitaxy approach. As surface affinity is a key parameter in self-assembly, three variations, or "flavors," of DSA template affinity are investigated regarding several success criteria such as morphology control or defectivity. More precisely, both the methodology to register DSA defects and the impact of process parameters on defectivity are detailed. Using the 300-mm pilot line available in LETI and Arkema's advanced materials, we investigate process optimization of DSA line/space patterning of a 38-nm period lamellar PS-b-PMMA BCP (L38). Our integration scheme is based on BCP self-assembly inside organic hard mask guiding patterns obtained using 193i-nm lithography. Defect analysis coupled with the fine tuning of process parameters (annealing, brush material) provided the optimum conditions for the L38 self-assembly. Using such conditions, DSA using the three affinity flavors is investigated by means of SEM top-view and cross-section review. Lithographic performances of one selected flavor are then evaluated with the comparison of process windows function of either commensurability, morphology, or roughness. This work is meant as a guideline for the graphoepitaxy optimization of materials and process parameters on a 300-mm platform.

  11. 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.

  12. 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.

  13. 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

  14. 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

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

    PubMed

    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

    2015-08-01

    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.

  16. The Role of Transcutaneous Electrical Nerve Stimulation in the Management of Temporomandibular Joint Disorder.

    PubMed

    Awan, Kamran Habib; Patil, Shankargouda

    2015-12-01

    Temporomandibular joint disorders (TMD) constitutes of a group of diseases that functionally affect the masticatory system, including the muscles of mastication and temporomandibular joint (TMJ). A number of etiologies with specific treatment have been identified, including the transcutaneous electrical nerve stimulation (TENS). The current paper presents a literature review on the use of TENS in the management of TMD patients. Temporomandibular joint disorder is very common disorder with approximately 75% of people showing some signs, while more than quarter (33%) having at least one symptom. An attempt to treat the pain should be made whenever possible. However, in cases with no defined etiology, starting with less intrusive and reversible techniques is prescribed. Transcutaneous electrical nerve stimulation is one such treatment modality, i.e. useful in the management of TMD. It comprises of controlled exposure of electrical current to the surface of skin, causing hyperactive muscles relaxation and decrease pain. Although the value of TENS to manage chronic pain in TMD patients is still controversial, its role in utilization for masticatory muscle pain is significant. However, an accurate diagnosis is essential to minimize its insufficient use. Well-controlled randomized trials are needed to determine the utilization of TENS in the management of TMD patients.

  17. Essential oil of croton nepetaefolius and its main constituent, 1,8-cineole, block excitability of rat sciatic nerve in vitro.

    PubMed

    Lima-Accioly, P M; Lavor-Porto, P R; Cavalcante, F S; Magalhães, P J C; Lahlou, S; Morais, S M; Leal-Cardoso, J H

    2006-12-01

    1. The effects of the essential oil of Croton nepetaefolius (EOCN) and its major constituent, 1,8-cineole, on the compound action potential (CAP) of nerve were investigated. 2. Experiments were performed in sciatic nerves dissected from Wistar rats, mounted in a moist chamber and stimulated at a frequency of 0.2 Hz, with electric pulses of 100 micros duration at 20-40 V. Evoked CAP were displayed on an oscilloscope and recorded on a computer. The CAP control parameters were as follows: peak-to-peak amplitude 8.1 +/- 0.6 mV (n = 15); conduction velocity 83.3 +/- 4.2 m/s (n = 15); chronaxie 58.0 +/- 6.8 msec (n = 6); and rheobase 2.8 +/- 0.1 V (n = 6). 3. Lower concentrations of EOCN (100 and 300 microg/mL) and 1,8-cineole (153 and 307 microg/mL; i.e. 1 and 2 mmol/L, respectively) had no significant effects on CAP control parameters throughout the entire recording period. However, at the end of 180 min exposure of the nerve to the drug, peak-to-peak amplitude was significantly (P < 0.05) reduced to 27.4 +/- 6.7 and 1.7 +/- 0.8% of control values by 500 and 1000 microg/mL EOCN, respectively (n = 6), and to 76.5 +/- 4.4, 70.0 +/- 3.9 and 14.8 +/- 4.1% of control values by 614, 920 and 1227 microg/mL (i.e. 4, 6 and 8 mmol/L) 1,8-cineole, respectively (n = 6). Regarding conduction velocity, at the end of the 180 min exposure period, this parameter was significantly reduced to 85.8 +/- 7.3 and 48.7 +/- 12.3% (n = 6) of control values by 500 and 1000 microg/mL EOCN, respectively, and to 86.4 +/- 4.5 and 76.1 +/- 5.2% (n = 6) by 920 and 1227 microg/mL 1,8-cineole, respectively. Chronaxie and rheobase were significantly increased by the higher concentrations of both EOCN and 1,8-cineole. 4. It is concluded that EOCN and its main constituent 1,8-cineole block nerve excitability in a concentration-dependent manner, an effect that was totally reversible with 1,8-cineole but not with EOCN. This suggests that other constituents of EOCN, in addition to 1,8-cineole, may contribute

  18. Topical airway anesthesia for awake fiberoptic intubation: Comparison between airway nerve blocks and nebulized lignocaine by ultrasonic nebulizer

    PubMed Central

    Gupta, Babita; Kohli, Santvana; Farooque, Kamran; Jalwal, Gopal; Gupta, Deepak; Sinha, Sumit; Chandralekha

    2014-01-01

    Overview: Awake fiberoptic bronchoscope (FOB) guided intubation is the gold standard of airway management in patients with cervical spine injury. It is essential to sufficiently anesthetize the upper airway before the performance of awake FOB guided intubation in order to ensure patient comfort and cooperation. This randomized controlled study was performed to compare two methods of airway anesthesia, namely ultrasonic nebulization of local anesthetic and performance of airway blocks. Materials and Methods: A total of 50 adult patients with cervical spine injury were randomly allocated into two groups. Group L received airway anesthesia through ultrasonic nebulization of 10 ml of 4% lignocaine and Group NB received airway blocks (bilateral superior laryngeal and transtracheal recurrent laryngeal) each with 2 ml of 2% lignocaine and viscous lignocaine gargles. FOB guided orotracheal intubation was then performed. Hemodynamic variables at baseline and during the procedure, patient recall, vocal cord visibility, ease of intubation, coughing/gagging episodes, and signs of lignocaine toxicity were noted. Results: The observations did not reveal any significant differences in demographics or hemodynamic parameters at any time during the study. However, the time taken for intubation was significantly lower in Group NB as compared with the Group L. Group L had an increased number of coughing/gagging episodes as compared with Group NB. Vocal cord visibility and ease of intubation were better in patients who received airway blocks and hence the amount of supplemental lignocaine used was less in this group. Overall patient comfort was better in Group NB with fewer incidences of unpleasant recalls as compared with Group L. Conclusion: Upper airway blocks provide better quality of anesthesia than lignocaine nebulization as assessed by patient recall of procedure, coughing/gagging episodes, ease of intubation, vocal cord visibility, and time taken to intubate. PMID:25538514

  19. A prospective, randomized, double-blind study of the anesthetic efficacy of sodium bicarbonate buffered 2% lidocaine with 1:100,000 epinephrine in inferior alveolar nerve blocks.

    PubMed

    Whitcomb, Michael; Drum, Melissa; Reader, Al; Nusstein, John; Beck, Mike

    2010-01-01

    The authors, using a crossover design, randomly administered, in a double-blind manner, inferior alveolar nerve (IAN) blocks using a buffered 2% lidocaine with 1:100,000 epinephrine/sodium bicarbonate formulation and an unbuffered 2% lidocaine with 1:100,000 epinephrine formulation at 2 separate appointments spaced at least 1 week apart. An electric pulp tester was used in 4-minute cycles for 60 minutes to test for anesthesia of the first and second molars, premolars, and lateral and central incisors. Anesthesia was considered successful when 2 consecutive 80 readings were obtained within 15 minutes, and the 80 reading was continuously sustained for 60 minutes. For the buffered 2% lidocaine with 1:100,000 epinephrine/sodium bicarbonate formulation, successful pulpal anesthesia ranged from 10-71%. For the unbuffered 2% lidocaine with 1:100,000 epinephrine formulation, successful pulpal anesthesia ranged from 10-72%. No significant differences between the 2 anesthetic formulations were noted. The buffered lidocaine formulation did not statistically result in faster onset of pulpal anesthesia or less pain during injection than did the unbuffered lidocaine formulation. We concluded that buffering a 2% lidocaine with 1:100,000 epinephrine with sodium bicarbonate, as was formulated in the current study, did not statistically increase anesthetic success, provide faster onset, or result in less pain of injection when compared with unbuffered 2% lidocaine with 1:100,000 epinephrine for an IAN block.

  20. The role of peripheral nerve fibers and their neurotransmitters in cartilage and bone physiology and pathophysiology.

    PubMed

    Grässel, Susanne G

    2014-01-01

    The peripheral nervous system is critically involved in bone metabolism, osteogenesis, and bone remodeling. Nerve fibers of sympathetic and sensory origin innervate synovial tissue and subchondral bone of diathrodial joints. They modulate vascularization and matrix differentiation during endochondral ossification in embryonic limb development, indicating a distinct role in skeletal growth and limb regeneration processes. In pathophysiological situations, the innervation pattern of sympathetic and sensory nerve fibers is altered in adult joint tissues and bone. Various resident cell types of the musculoskeletal system express receptors for sensory and sympathetic neurotransmitters. Osteoblasts, osteoclasts, mesenchymal stem cells, synovial fibroblasts, and different types of chondrocytes produce distinct subtypes of adrenoceptors, receptors for vasointestinal peptide, for substance P and calcitonin gene-related peptide. Many of these cells even synthesize neuropeptides such as substance P and calcitonin gene-related peptide and are positive for tyrosine-hydroxylase, the rate-limiting enzyme for biosynthesis of catecholamines. Sensory and sympathetic neurotransmitters modulate osteo-chondrogenic differentiation of mesenchymal progenitor cells during endochondral ossification in limb development. In adults, sensory and sympathetic neurotransmitters are critical for bone regeneration after fracture and are involved in the pathology of inflammatory diseases as rheumatoid arthritis which manifests mainly in joints. Possibly, they might also play a role in pathogenesis of degenerative joint disorders, such as osteoarthritis. All together, accumulating data imply that sensory and sympathetic neurotransmitters have crucial trophic effects which are critical for proper limb formation during embryonic skeletal growth. In adults, they modulate bone regeneration, bone remodeling, and articular cartilage homeostasis in addition to their classic neurological actions.

  1. Management of acute postoperative pain with continuous intercostal nerve block after single port video-assisted thoracoscopic anatomic resection

    PubMed Central

    Hsieh, Ming-Ju; Wang, Kuo-Cheng; Liu, Hung-Pin; Gonzalez-Rivas, Diego; Wu, Ching-Yang; Liu, Yun-Hen; Wu, Yi-Cheng; Chao, Yin-Kai

    2016-01-01

    Background Effective postoperative pain control for thoracic surgery is very important, not only because it reduces pulmonary complications but also because it accelerates the pace of recovery. Moreover, it increases patients’ satisfaction with the surgery. In this study, we present a simple approach involving the safe placement of intercostal catheter (ICC) after single port video-assisted thoracoscopic surgery (VATS) anatomic resection and we evaluate postoperative analgesic function with and without it. Methods We identified patients who underwent single port anatomic resection with ICC placed intraoperatively as a route for continuous postoperative levobupivacaine (0.5%) administration and retrospectively compared them with a group of single port anatomic resection patients without ICC. The operation time, postoperative day 0, 1, 2, 3 and discharge day pain score, triflow numbers, narcotic requirements, drainage duration and post-operative hospital stay were compared. Results In total, 78 patients were enrolled in the final analysis (39 patients with ICC and 39 without). We found patients with ICC had less pain sensation numerical rating scale (NRS) on postoperative day 0, 1 (P=0.023, <0.001) and better triflow performance on postoperative day 1 and 2 (P=0.015, 0.032). In addition, lower IV form morphine usage frequency and dosage (P=0.009, 0.017), shorter chest tube drainage duration (P=0.001) and postoperative stay (P=0.005) were observed in the ICC group. Conclusions Continuous intercostal nerve blockade by placing an ICC intraoperatively provides effective analgesia for patients undergoing single port VATS anatomic resection. This may be considered a viable alternative for postoperative pain management. PMID:28149550

  2. 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

  3. 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.

  4. Subperiosteal hematoma from peribulbar block during cataract surgery leading to optic nerve compression in a patient with parahemophilia

    PubMed Central

    Khokhar, Sudarshan; Nayak, Bhagabat; Patil, Bharat; Changole, Milind Devidas; Sinha, Gautam; Sharma, Reetika; Nayak, Lipika

    2015-01-01

    A 17-year-old male presented with gradual painless diminution of vision since childhood. Slit lamp examination revealed both eyes having congenital cataract. Right eye lens aspiration was performed but was uneventful, and he prepared for left eye surgery after 7 days. Immediately after giving a peribulbar block, a complete akinesia, tight eyelids, and stony hard eyeball was noted. An abaxial proptosis of 7 mm was noted. Lateral canthotomy and inferior cantholysis were done and proptosis reduced to 5 mm. Bleeding time–clotting time was normal. Proptosis worsened to 8 mm the next day. Contrast-enhanced computed tomography scan showed inferolateral subperiosteal hematoma, but drainage could not be performed due to prolonged prothrombin time and activated prothrombin time. Fresh frozen plasma was transfused. Tarsorrhaphy was performed for exposure keratopathy after his coagulation profile became normal. Hematology evaluation after 2 weeks detected factor V deficiency, and was diagnosed as Owren’s disease or parahemophilia. PMID:26664247

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

    NASA Astrophysics Data System (ADS)

    Tsou, Chin-Hua; Smith, Phillip J.

    1990-01-01

    , which in view of the subsequent role of scale interactions in the block development suggests an indirect role for thermal advection.

  6. Vagal nerve stimulation blocks interleukin 6-dependent synaptic hyperexcitability induced by lipopolysaccharide-induced acute stress in the rodent prefrontal cortex

    PubMed Central

    Garcia-Oscos, Francisco; Peña, David; Housini, Mohammad; Cheng, Derek; Lopez, Diego; Borland, Michael S.; Salgado-Delgado, Roberto; Salgado, Humberto; D’Mello, Santosh; Kilgard, Michael P.; Rose-John, Stefan; Atzori, Marco

    2016-01-01

    The ratio between synaptic inhibition and excitation (sI/E) is a critical factor in the pathophysiology of neuropsychiatric disease. We recently described a stress-induced interleukin-6 dependent mechanism leading to a decrease in sI/E in the rodent temporal cortex. The aim of the present study was to determine whether a similar mechanism takes place in the prefrontal cortex, and to elaborate strategies to prevent or attenuate it. We used aseptic inflammation (single acute injections of lipopolysaccharide, LPS, 10 mg/kg) as stress model, and patch-clamp recording on a prefrontal cortical slice preparation from wild-type rat and mice, as well as from transgenic mice in which the inhibitor of IL-6 trans-signaling sgp130Fc was produced in a brain-specific fashion (sgp130Fc mice). The anti-inflammatory reflex was activated either by vagal nerve stimulation or peripheral administration of the nicotinic α7 receptor agonist PHA543613. We found that the IL-6-dependent reduction in prefrontal cortex synaptic inhibition was blocked in sgp130Fc mice, or – in wild-type animals – upon application sgp130Fc. Similar results were obtained by activating the “anti-inflammatory reflex” – a neural circuit regulating peripheral immune response – by stimulation of the vagal nerve or through peripheral administration of the α7 nicotinic receptor agonist PHA543613. Our results indicate that the prefrontal cortex is an important potential target of IL-6 mediated trans-signaling, and suggest a potential new avenue in the treatment of a large class of hyperexcitable neuropsychiatric conditions, including epilepsy, schizophrenic psychoses, anxiety disorders, autism spectrum disorders, and depression. PMID:25128387

  7. Role of endogenous hydrogen sulfide in nerve-evoked relaxation of pig terminal bronchioles.

    PubMed

    Fernandes, Vítor S; Recio, Paz; López-Oliva, Elvira; Martínez, María Pilar; Ribeiro, Ana Sofía; Barahona, María Victoria; Martínez, Ana Cristina; Benedito, Sara; Agis-Torres, Ángel; Cabañero, Alberto; Muñoz, Gemma M; García-Sacristán, Albino; Orensanz, Luis M; Hernández, Medardo

    2016-12-01

    Hydrogen sulfide (H2S) is a gasotransmitter employed for intra- and inter-cellular communication in almost all organ systems. This study investigates the role of endogenous H2S in nerve-evoked relaxation of pig terminal bronchioles with 260 μm medium internal lumen diameter. High expression of the H2S synthesis enzyme cystathionine γ-lyase (CSE) in the bronchiolar muscle layer and strong CSE-immunoreactivity within nerve fibers distributed along smooth muscle bundles were observed. Further, endogenous H2S generated in bronchiolar membranes was reduced by CSE inhibition. In contrast, cystathionine β-synthase expression, another H2S synthesis enzyme, however was not consistently detected in the bronchiolar smooth muscle layer. Electrical field stimulation (EFS) and the H2S donor P-(4-methoxyphenyl)-P-4-morpholinylphosphinodithioic acid (GYY4137) evoked smooth muscle relaxation. Inhibition of CSE, nitric oxide (NO) synthase, soluble guanylyl cyclase (sGC) and of ATP-dependent K(+), transient receptor potential A1 (TRPA1) and transient receptor potential vanilloid 1 (TRPV1) channels reduced the EFS relaxation but failed to modify the GYY4137 response. Raising extracellular K(+) concentration inhibited the GYY4137 relaxation. Large conductance Ca(2+)-activated K(+) channel blockade reduced both EFS and GYY4137 responses. GYY4137 inhibited the contractions induced by histamine and reduced to a lesser extent the histamine-induced increases in intracellular [Ca(2+)]. These results suggest that relaxation induced by EFS in the pig terminal bronchioles partly involves the H2S/CSE pathway. H2S response is produced via NO/sGC-independent mechanisms involving K(+) channels and intracellular Ca(2+) desensitization-dependent pathways. Thus, based on our current results H2S donors might be useful as bronchodilator agents for the treatment of lung diseases with persistent airflow limitation, such as asthma and chronic obstructive lung disease.

  8. A role of amphiphysin in synaptic vesicle endocytosis suggested by its binding to dynamin in nerve terminals.

    PubMed Central

    David, C; McPherson, P S; Mundigl, O; de Camilli, P

    1996-01-01

    Amphiphysin, a major autoantigen in paraneoplastic Stiff-Man syndrome, is an SH3 domain-containing neuronal protein, concentrated in nerve terminals. Here, we demonstrate a specific, SH3 domain-mediated, interaction between amphiphysin and dynamin by gel overlay and affinity chromatography. In addition, we show that the two proteins are colocalized in nerve terminals and are coprecipitated from brain extracts consistent with their interactions in situ. We also report that a region of amphiphysin distinct from its SH3 domain mediates its binding to the alpha c subunit of AP2 adaptin, which is also concentrated in nerve terminals. These findings support a role of amphiphysin in synaptic vesicle endocytosis. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 PMID:8552632

  9. Population pharmacokinetic model of free and total ropivacaine after transversus abdominis plane nerve block in patients undergoing liver resection

    PubMed Central

    Ollier, Edouard; Heritier, Fabrice; Bonnet, Caroline; Hodin, Sophie; Beauchesne, Brigitte; Molliex, Serge; Delavenne, Xavier

    2015-01-01

    Aims The aim of this study was to develop a pharmacokinetic model in order to characterize the free and total ropivacaine concentrations after transversus abdominis plane block in a population of patients undergoing liver resection surgery. In particular, we evaluated the impact of the size of liver resection on ropivacaine pharmacokinetics. Methods This work is based on a single-centre, double-blinded, randomized, placebo-controlled study. Among the 39 patients included, 19 patients were randomized to the ropivacaine group. The free and total ropivacaine concentrations were measured in nine or 10 blood samples per patient. A pharmacokinetic model was built using a nonlinear mixed-effect modelling approach. Results The free ropivacaine concentrations remained under the previously published toxic threshold. A one-compartment model, including protein binding site with a first-order absorption, best described the data. The protein binding site concentration was considered as a latent variable. Bodyweight, the number of resected liver segments and postoperative fibrinogen evolution were, respectively, included in the calculation of the volume of distribution, clearance and binding site production rate. The resection of three or more liver segments was associated with a 53% decrease in the free ropivacaine clearance. Conclusions Although large liver resections were associated with lower free ropivacaine clearance, the ropivacaine pharmacokinetic profile remained within the safe range after this type of surgery. PMID:25557141

  10. Multitumor "sausage" blocks in immunohistochemistry. Simplified method of preparation, practical uses, and roles in quality assurance.

    PubMed

    Miller, R T; Groothuis, C L

    1991-08-01

    This report describes a simplified method for preparing multitumor sausage blocks (MTSBs) for use in immunohistochemical procedures. Rather than relying on previously processed paraffin blocks as a source of material, this procedure involves procuring tissue at the time of gross specimen examination. The tissue is processed along with routine surgical pathologic material, and the paraffinized samples are placed in "storage cassettes" for easy cataloging and storage. Thin strips are cut from the tissue in the "storage cassettes" and combined by dripping liquid paraffin onto them while they are rolled between the thumbs and forefingers, somewhat like making a cigarette. This results in a tissue "log." Transverse sections of the "log" are embedded in paraffin blocks and used as MTSBs. Practical uses of MTSBs are discussed, and their role in quality assurance is stressed.

  11. 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

  12. Dissecting the roles of Ephrin-A3 in malignant peripheral nerve sheath tumor by TALENs.

    PubMed

    Wang, Zhengguang; Liu, Zhendong; Liu, Bo; Liu, Gengyan; Wu, Song

    2015-07-01

    Malignant peripheral nerve sheath tumor (MPNST) is a rare and aggressive soft tissue sarcoma for which effective treatments have not yet been established due to poor understanding of its pathogenesis. Our previous study indicated that miR-210-mediated Ephrin-A3 (EFNA3) promotion of proliferation and invasion of MPNST cells plays an important role in MPNST tumorigenesis and progression. The purpose of the present study was to further investigate the roles of EFNA3 in MPNST. Constructed transcription activator-like effector nucleases (TALENs) and lentiviral vectors were transfected into MPNST ST88-14 (NF1 wild-type) and sNF96.2 (NF1 mutant type) cell lines to obtain gain- and loss-of-function cell lines for the EFNA3 function study. The results showed that the knockout of ENFA3 increased cellular viability and invasiveness of the MPNST cells. However, the adhesion ability of MPNST cells was enhanced or inhibited when EFNA3 was overexpressed or knocked out, respectively. It was also observed that knockout of EFNA3 significantly decreased the expression of phosphorylated FAK (p-FAK) and the tumor necrosis factor α (TNF-α) compared to that in the control cells, yet the expression of phosphatidylinositol 3-kinase (PI3K), GTPase, integrins, vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1α (HIF-α) increased significantly. Inversely, overexpression of EFNA3 significantly increased the expression of p-FAK and TNF-α compared to that in the control cells, yet the expression of PI3K, GTPase, integrins, VEGF and HIF-α decreased significantly. The results indicated that EFNA3 serves as a tumor suppressor in MPNST cells and it may play a critical role in the focal adhesion kinase (FAK) signaling and VEGF-associated tumor angiogenesis pathway. These findings may not only facilitate the better understanding of MPNST pathogenesis, but also suggest EFNA3 as a promising target for MPNST treatment.

  13. The role of microstructured and interconnected pore channels in a collagen-based nerve guide on axonal regeneration in peripheral nerves.

    PubMed

    Bozkurt, Ahmet; Lassner, Franz; O'Dey, Dan; Deumens, Ronald; Böcker, Arne; Schwendt, Tilman; Janzen, Christoph; Suschek, Christoph V; Tolba, Rene; Kobayashi, Eiji; Sellhaus, Bernd; Tholl, S; Eummelen, Lizette; Schügner, Frank; Damink, Leon Olde; Weis, Joachim; Brook, Gary A; Pallua, Norbert

    2012-02-01

    The use of bioengineered nerve guides as alternatives for autologous nerve transplantation (ANT) is a promising strategy for the repair of peripheral nerve defects. In the present investigation, we present a collagen-based micro-structured nerve guide (Perimaix) for the repair of 2 cm rat sciatic nerve defects. Perimaix is an open-porous biodegradable nerve guide containing continuous, longitudinally orientated channels for orientated nerve growth. The effects of these nerve guides on axon regeneration by six weeks after implantation have been compared with those of ANT. Investigation of the regenerated sciatic nerve indicated that Perimaix strongly supported directed axon regeneration. When seeded with cultivated rat Schwann cells (SC), the Perimaix nerve guide was found to be almost as supportive of axon regeneration as ANT. The use of SC from transgenic green-fluorescent-protein (GFP) rats allowed us to detect the viability of donor SC at 1 week and 6 weeks after transplantation. The GFP-positive SC were aligned in a columnar fashion within the longitudinally orientated micro-channels. This cellular arrangement was not only observed prior to implantation, but also at one week and 6 weeks after implantation. It may be concluded that Perimaix nerve guides hold great promise for the repair of peripheral nerve defects.

  14. 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

  15. Possible role of alpha-lipoic acid in the treatment of peripheral nerve injuries

    PubMed Central

    2010-01-01

    Recent findings on the antioxidant effects of pretreatment with α-lipoic acid (α-LA) on the crush injury of rat sciatic nerve confirm the possible usefulness of α-LA administration in humans with peripheral nerve injuries. We discussed this issue in relation with our recent results in which the combined employment of α-LA and γ-linolenic acid with a rehabilitation program for six weeks reduced sensory symptoms and neuropathic pain in patients with compressive radiculopathy syndrome from disc-nerve root conflict in comparison with patients submitted to rehabilitation program alone for six weeks. PMID:20807428

  16. Differential expression and potential role of SOCS1 and SOCS3 in Wallerian degeneration in injured peripheral nerve

    PubMed Central

    Girolami, Elizabeth I.; Bouhy, Delphine; Haber, Michael; Johnson, Howard; David, Samuel

    2009-01-01

    Pro-inflammatory chemokines and cytokines play an important role in Wallerian degeneration (WD) after peripheral nerve injury. These pro-inflammatory signals are “turned-off” in a timely manner to ensure that the inflammatory response in the injured nerve is limited. The factors that regulate the turning-off of the pro-inflammatory state are not fully understood. The suppressors of cytokine signaling (SOCS) proteins are potential candidates that could limit the inflammatory response by acting to regulate cytokine signaling at the intracellular level. In this work we show that the expression SOCS1 and SOCS3 proteins differ from each other during WD in the mouse sciatic nerve after cut/ligation and crush injuries. SOCS1 is mainly expressed by macrophages and its expression is inversely correlated with phosphorylation of JAK2 and STAT3 signaling proteins and the expression of pro-inflammatory cytokines IL-1β and TNFα. In addition, treatment of cut/ligated nerves, which express lower levels of SOCS1 as compared to crush injury, with a SOCS1 mimetic peptide leads to a decrease in macrophage numbers at 14 days post-injury and reduces IL-1β mRNA expression 1 day post-injury. In contrast, SOCS3 expression is restricted mainly to Schwann cells and is negatively correlated with the expression of IL-6 and LIF. These data suggest that SOCS1 and SOCS3 may play different roles in WD and provide a better understanding of some of the potential regulatory mechanisms that may control inflammation and regeneration in the injured peripheral nerve. PMID:19576891

  17. 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.

  18. Lower body nerve stretch: a role in essential hypertension or pre-eclampsia?

    PubMed

    Milne, B

    1996-10-01

    Despite the relatively high incidence of essential hypertension and pregnancy-induced hypertension, the etiologies of these disorders remain enigmatic. A link between stretching of neural structures in the lower body and the induction of hypertension in these disorders is hypothesized. Hypertension has been documented in patients undergoing femoral and tibial lengthening procedures; in experimental models the stretching of lower extremity nerves appeared to be responsible for the increase in blood pressure with bone lengthening. The upright posture of humans puts an added strain on nerves and an increased pressure on lumbar disks may put increasing tension on the nerve roots. The resultant nerve stretch in pregnant women may be exacerbated by the hormone relaxin. A possible link between the stretching of neural structures and the genesis of essential hypertension or pre-eclampsia/eclampsia is hypothesized.

  19. Role of CD44 in Malignant Peripheral Nerve Sheath Tumor Growth and Metastasis

    DTIC Science & Technology

    2002-09-01

    Malignant peripheral nerve sheath tumors ( MPNSTs ) are aggressive malignancies that arise within peripheral nerves. These tumors occur with increased...and abnormal expression of the epidermal growth factor receptor (EGFR). We previously found that MPNSTs express increased levels of the CD44 family...kinase activity (and not increased Ras-GTP) contributes to MPNST cell invasion. We further find that EGFR contributes at least part of the elevated Src

  20. 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.

  1. Morphometric study on mandibular foramen and incidence of accessory mandibular foramen in mandibles of south Indian population and its clinical implications in inferior alveolar nerve block

    PubMed Central

    RaviVarman, C.; Manoranjitham, R.; Veeramuthu, M.

    2016-01-01

    The mandibular foramen is a landmark for procedures like inferior alveolar nerve block, mandibular implant treatment, and mandibular osteotomies. The present study was aimed to identify the precise location of the mandibular foramen and the incidence of accessory mandibular foramen in dry adult mandibles of South Indian population. The distance of mandibular foramen from the anterior border of the ramus, posterior border of the ramus, mandibular notch, base of the mandible, third molar, and apex of retromolar trigone was measured with a vernier caliper in 204 mandibles. The mean distance of mandibular foramen from the anterior border of ramus of mandible was 17.11±2.74 mm on the right side and 17.41±3.05 mm on the left side, from posterior border was 10.47±2.11 mm on the right side and 9.68±2.03 mm on the left side, from mandibular notch was 21.74±2.74 mm on the right side and 21.92±3.33 mm on the left side, from the base of the ramus was 22.33±3.32 mm on the right side and 25.35±4.5 mm on the left side, from the third molar tooth was 22.84±3.94 mm on the right side and 23.23±4.21 mm on the left side, from the apex of retromolar trigone was 12.27±12.13 mm on the right side and 12.13±2.35 mm on the left side. Accessory mandibular foramen was present in 32.36% of mandibles. Knowledge of location mandibular foramen is useful to the maxillofacial surgeons, oncologists and radiologists. PMID:28127498

  2. 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

  3. Chemical interactions and their role in the microphase separation of block copolymer thin films.

    PubMed

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

    2009-08-25

    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.

  4. 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

  5. Exploring the role of nerve growth factor in multiple sclerosis: implications in myelin repair.

    PubMed

    Acosta, C M R; Cortes, C; MacPhee, H; Namaka, M P

    2013-12-01

    Multiple sclerosis (MS) is a chronic disease resulting from targeted destruction of central nervous system (CNS) myelin. MS is suggested to be an autoimmune disease involving the pathogenic activation of CD4(+) T cells by a foreign antigen in the peripheral blood. The activated CD4(+) T cells liberate inflammatory cytokines that facilitate the breakdown of the blood-brain barrier (BBB) promoting their passage into the CNS. Inside the CNS, CD4(+) T cells become re-activated by myelin proteins sharing a similar structure to the foreign antigen that initially triggered the immune response. The CD4(+) T cells continue to liberate inflammatory cytokines, such as tumor necrosis factor α (TNFα), which activates macrophages and antibodies responsible for the phagocytosis of myelin. Acute CNS lesions can be re-myelinated, however, the repair of chronic demyelinating lesions is limited, leading to permanent neurological deficits. Although current MS treatments reduce severity and slow disease progression, they do not directly repair damaged myelin. Henceforth, recent treatment strategies have focused on neurotrophins, such as nerve growth factor (NGF) for myelin repair. NGF promotes axonal regeneration, survival, protection and differentiation of oligodendrocytes (OGs) and facilitates migration and proliferation of oligodendrocyte precursors (OPs) to the sites of myelin damage. NGF also directly regulates key structural proteins that comprise myelin. Interestingly, NGF also induces the production of brain-derived neurotrophic factor (BDNF), another integral neurotrophin involved in myelination. The intricate signaling between neurotrophins and cytokines that governs myelin repair supports the role of NGF as a leading therapeutic candidate in white matter disorders, such as MS.

  6. The role of vascular damage and fibrosis in the pathogenesis of nerve root damage.

    PubMed

    Jayson, M I

    1992-06-01

    Vascular damage and fibrosis are common within the vertebral canal and intervertebral foramen. The grossest examples occur in patients who have previously undergone oil-based myelography or spinal surgery. The mechanisms of fibrosis in the latter instance may be related to persisting cotton debris from sponges used during the operation. This debris may act as a fibrogenic stimulus. However, in cadaveric studies of nonoperated spines, the author and his colleagues have found clear evidence of vascular damage and fibrosis within the spines, and this vascular damage is significantly related to the severity of degenerative disk disease. Degenerative disk disease with osteophytic proliferation and disk protrusion may lead to compression of epidural veins with dilation of noncompressed veins. There is a significant statistical relationship between the extent of the disk degeneration and prolapse and the evidence of venous compression and dilatation. The dilatated veins may contain antemortem thromboses. In turn, there is a significant statistical relationship between the evidence for venous obstruction and perineural fibrosis. Such a relationship also exists between perineural fibrosis and neuronal atrophy. If therefore appears likely that venous obstruction with resultant hypoxia is an important mechanism leading to nerve root damage. In the peripheral blood, significant defects in the fibrinolytic system correlate with the severity of the symptoms. However, it was not possible to correlate these changes with individual clinical or imaging features. These fibrinolytic changes are recognized as markers of vascular damage and may reflect the pathologic processes that the author and his colleagues have demonstrated. It is uncertain whether they play any secondary pathogenic role in the chronicity of these back problems.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Facial Nerve Recovery in KbDb and C1q Knockout Mice: A Role for Histocompatibility Complex 1

    PubMed Central

    Akdagli, Seden; Williams, Ryan A.; Kim, Hyun J.; Yan, Yuling; Mustapha, Mirna

    2016-01-01

    Background: Understanding the mechanisms in nerve damage can lead to better outcomes for neuronal rehabilitation. The purpose of our study was to assess the effect of major histocompatibility complex I deficiency and inhibition of the classical complement pathway (C1q) on functional recovery and cell survival in the facial motor nucleus (FMN) after crush injury in adult and juvenile mice. Methods: A prospective blinded analysis of functional recovery and cell survival in the FMN after a unilateral facial nerve crush injury in juvenile and adult mice was undertaken between wild-type, C1q knockout (C1q−/−), and KbDb knockout (KbDb−/−) groups. Whisker function was quantified to assess functional recovery. Neuron counts were performed to determine neuron survival in the FMN after recovery. Results: After facial nerve injury, all adult wild-type mice fully recovered. Juvenile mice recovered incompletely corresponding to a greater neuron loss in the FMN of juveniles compared with adults. The C1q−/− juvenile and adult groups did not differ from wild type. The KbDb−/− adults demonstrated 50% recovery of whisker movement and decreased cell survival in FMN. The KbDb−/− juvenile group did not demonstrate any difference from control group. Conclusion: Histocompatibility complex I plays a role for neuroprotection and enhanced facial nerve recovery in adult mice. Inhibition of the classical complement pathway alone does not affect functional recovery or neuronal survival. The alternative and mannose binding pathways pose alternative means for activating the final components of the pathway that may lead to acute nerve damage. PMID:28293529

  8. Presynaptic histamine H2 receptors modulate the sympathetic nerve transmission in the isolated rat vas deferens; no role for H3-receptors.

    PubMed

    Poli, E; Todorov, S; Pozzoli, C; Bertaccini, G

    1994-10-01

    The modulatory activity mediated by histamine receptors on the sympathetic nerve transmission was investigated in the rat vas deferens. Agonists and antagonists acting at the different histamine receptor subtypes (H1, H2 and H3) were tested on electrically-driven preparations in vitro. Low-frequency stimulation (0.1 Hz) evoked muscle contractions almost completely-sustained by ATP release, while at high-frequency stimulation (5-10 Hz) norepinephrine was mainly involved. The H1 receptor agonists, pyridilethylamine and 2-(2 aminoethyl)thiazole, enhanced the electrically evoked twitch responses, but not contractions induced by exogenously-applied norepinephrine and ATP. These effects were prevented by the H1-blocking drugs, mepyramine and phenyramine, but only at high concentrations (10 mumol/l). All these H1-antagonists strongly enhanced muscle response to electrical stimulation. The H2 receptor agonists, dimaprit, amthamine and impromidine, reduced the contractions evoked by field stimulation, but not by exogenously applied norepinephrine and ATP, the effect being antagonised by H2-blocking drugs, ranitidine and famotidine. The H3 receptor agonist, R(alpha)-methylhistamine, reduced the electrically evoked muscle contractions, the effect being not modified by the selective H3-blocking drug, thioperamide, but prevented by famotidine. These data suggest that rat vas deferens contains presynaptic histamine H2 receptors, able to mediate inhibitory effects on the sympathetic transmission, while histamine H3 receptors are apparently not involved. On the contrary, the role of H1 is still unclear, since both agonists and antagonists may have the same effects.

  9. A Possible Role of Neuroglobin in the Retina After Optic Nerve Injury: A Comparative Study of Zebrafish and Mouse Retina.

    PubMed

    Sugitani, Kayo; Koriyama, Yoshiki; Ogai, Kazuhiro; Wakasugi, Keisuke; Kato, Satoru

    2016-01-01

    Neuroglobin (Ngb) is a new member of the family of heme proteins and is specifically expressed in neurons of the central and peripheral nervous systems in all vertebrates. In particular, the retina has a 100-fold higher concentration of Ngb than do other nervous tissues. The role of Ngb in the retina is yet to be clarified. Therefore, to understand the functional role of Ngb in the retina after optic nerve injury (ONI), we used two types of retina, from zebrafish and mice, which have permissible and non-permissible capacity for nerve regeneration after ONI, respectively. After ONI, the Ngb protein in zebrafish was upregulated in the amacrine cells within 3 days, whereas in the mouse retina, Ngb was downregulated in the retinal ganglion cells (RGCs) within 3 days. Zebrafish Ngb (z-Ngb) significantly enhanced neurite outgrowth in retinal explant culture. According to these results, we designed an overexpression experiment with the mouse Ngb (m-Ngb) gene in RGC-5 cells (retinal precursor cells). The excess of m-Ngb actually rescued RGC-5 cells under hypoxic conditions and significantly enhanced neurite outgrowth in cell culture. These data suggest that mammalian Ngb has positive neuroprotective and neuritogenic effects that induce nerve regeneration after ONI.

  10. The role of endogenous serotonin in methamphetamine-induced neurotoxicity to dopamine nerve endings of the striatum.

    PubMed

    Thomas, David M; Angoa Pérez, Mariana; Francescutti-Verbeem, Dina M; Shah, Mrudang M; Kuhn, Donald M

    2010-11-01

    Methamphetamine (METH) is a neurotoxic drug of abuse that damages the dopamine (DA) neuronal system in a highly delimited manner. The brain structure most affected by METH is the striatum where long-term DA depletion and microglial activation are maximal. Endogenous DA has been implicated as a critical participant in METH-induced neurotoxicity, most likely as a substrate for non-enzymatic oxidation by METH-generated reactive oxygen species. The striatum is also extensively innervated by serotonin (5HT) nerve endings and this neurochemical system is modified by METH in much the same manner as seen in DA nerve endings (i.e., increased release of 5HT, loss of function in tryptophan hydroxylase and the serotonin transporter, long-term depletion of 5HT stores). 5HT can also be modified by reactive oxygen species to form highly reactive species that damage neurons but its role in METH neurotoxicity has not been assessed. Increases in 5HT levels with 5-hydroxytryptophan do not change METH-induced neurotoxicity to the DA nerve endings as revealed by reductions in DA, tyrosine hydroxylase and dopamine transporter levels. Partial reductions in 5HT with p-chlorophenylalanine are without effect on METH toxicity, despite the fact that p-chlorophenylalanine largely prevents METH-induced hyperthermia. Mice lacking the gene for brain tryptophan hydroxylase 2 are devoid of brain 5HT and respond to METH in the same manner as wild-type controls, despite showing enhanced drug-induced hyperthermia. Taken together, the present results indicate that endogenous 5HT does not appear to play a role in METH-induced damage to DA nerve endings of the striatum.

  11. The role of OCT in the differential diagnosis between buried optic nerve drusen and papilloedema.

    PubMed

    Rebolleda, G; Muñoz-Negrete, F J

    2016-09-01

    Buried optic nerve head drusen are one of the most common causes of pseudo-papilloedema. In this review, we have chronologically addressed several useful traits in the differential diagnosis of a true papilloedema, using the different features of optical coherence tomography (OCT). The specificity of these features has improved at the same time as the improvement in penetration capability and resolution of newer OCT devices. Spectral domain OCT, and more specifically the enhanced depth imaging (EDI) technology, represents a turning point in directly visualise drusen, to quantify their size and to recognise their impact on neighbouring structures inside the optic nerve head.

  12. Sesame oil improves functional recovery by attenuating nerve oxidative stress in a mouse model of acute peripheral nerve injury: role of Nrf-2.

    PubMed

    Hsu, Che-Chia; Huang, Hui-Cheng; Wu, Po-Ting; Tai, Ta-Wei; Jou, I-Ming

    2016-12-01

    Peripheral nervous injury (PNI) is a common form of trauma in modern society, especially in sport players. Despite the advance of therapy for PNI, the recovery of function can never reach the preinjury level after treatments. Recently, inhibiting neural oxidative stress shows a beneficial effect in improving functional recovery after PNI. In addition, sesame oil has been reported to possess the excellent antioxidative properties. However, whether sesame oil can improve the functional recovery after PNI by its antioxidative effect has never been investigated. Thirty mice were randomly divided into five groups of six: group I mice received sham operation; group II mice received sciatic nerve crush; and groups III-V mice daily ingested 0.5, 1 and 2 ml/kg of sesame oil for 6 days, respectively, after sciatic nerve crush. Oxidative stress, GAP43 and nuclear Nrf2 levels as well as spinal somatosensory evoked potentials were assessed on day 6, while paw withdrawal latency and sciatic function index were assessed on days 0, 3, and 6. Sesame oil significantly decreased lipid peroxidation and increased nuclear factor erythroid 2-related factor 2 and GAP43 expression in sciatic nerve. Furthermore, sesame oil improved electrophysiological and functional assessments in mice with sciatic nerve crush. In conclusion, sesame oil may improve nerve functional recovery by attenuating nerve oxidative stress in mouse acute peripheral nerve injury. Further, application of natural product sesame oil may be an alternative approach for improving nerve functional recovery in the clinical setting.

  13. Role of fixation in posttraumatic nerve injury recovery in displaced mandibular angle fracture

    PubMed Central

    Singh, R. K.; Pal, U. S.; Singh, Pranshu; Singh, Geeta

    2016-01-01

    Objective: The objective of this study was to assess the effectiveness of different types of fixation in the enhancement of posttraumatic inferior alveolar nerve (IAN) recovery in displaced mandibular angle fracture and to establish. Patients and Methods: Thirty patients of displaced mandibular angle fracture were treated with preangulated plate and three-dimensional (3D) matrix plate in two groups and were observed during follow-up at 04,06 and 12 weeks along with other parameters. Results: Fifteen patients were treated with preangulated plate and 15 patients with 3D matrix miniplate. There was early nerve recovery in Group A than Group B, with residual paresthesia 20% in Group A and 26.6% in Group B at the end of 12-week follow-up. Conclusion: The displaced mandibular angle fracture with posttraumatic IAN paresthesia treated with preangulated plate has shown evidence of early nerve recovery than those fractures were treated with matrix miniplate. The fracture fragments displaced more than 9 mm have shown poor nerve recovery in both groups. PMID:28163475

  14. [The role of sensory nerves in the development of inflammation of oral tissues].

    PubMed

    Olgart, L

    1998-01-01

    Experimental stimulation and clinical procedures applied on the tooth crown cause vascular reactions in the dental pulp of cats and rats. These reactions depend on the activation of trigeminal afferent nerves and release of neuropeptides. A brief stimulation causes vasodilation, which is mainly mediated by calcitonin gene-related peptide (CGRP). A longer stimulation results in plasma extravasation which is mediated mainly by substance P (SP) and prostaglandins in the pulp. In adjacent oral tissues the mechanisms following stimulation or local irritation are more complex and other mediators are also involved. Nitric oxide (NO) which is instantly produced in the tissues is such a novel mediator. The chemosensitive nature of the nerves involved (capsaicin sensitive) may lead to their activation also by inflammatory mediators released in the tissues. Thus, sensory nerves may modulate the progress of inflammation. Since sensory nerves in oral tissues are often the first structures to be activated during clinical procedures, tissue reactions that occur can be assumed to be initiated and perpetuated by the sensory neuropeptides. Much work is now made to modulate the sensory nerveinduced cascade of events in oral tissues to find new treatment strategies.

  15. Landmark-based versus ultrasound-guided ilioinguinal/iliohypogastric nerve blocks in the treatment of chronic postherniorrhaphy groin pain: a retrospective study

    PubMed Central

    Trainor, Drew; Moeschler, Susan; Pingree, Matthew; Hoelzer, Brian; Wang, Zhen; Mauck, William; Qu, Wenchun

    2015-01-01

    Background Chronic postherniorrhaphy groin pain (CPGP) is a debilitating condition, which is often refractory to conservative medical management. To our knowledge, there have been no studies directly comparing landmarked-based and ultrasound-guided approaches in this population. Objective To compare the effectiveness of landmark-based and ultrasound-guided ilioinguinal/iliohypogastric nerve blocks in the treatment of CPGP. Study design This is a retrospective chart review of patients who presented to our tertiary care pain medicine clinic with a diagnosis of CPGP. Inclusion criteria were the following: age >18 years, diagnosis of groin pain, and prior history of herniorrhaphy. Exclusion criteria included those who were seen for initial consultation but were lost to follow-up. Primary outcomes were 50% or greater reduction in pain on visual analog scale (VAS). Secondary outcomes were 30% or greater reduction in VAS pain score, changes in VAS pain scores, and reported complications. Results A total of 36 patients were included in the study. Of them, 20 patients underwent the landmark-based and 16 underwent the ultrasound-guided techniques. There was no significant difference in baseline demographics. The average VAS score preinjection was 7.08 in the landmark-based and 7.0 in the ultrasound-guided groups (P=0.65). A total of 14 patients (70%) in the landmark-based and eleven patients (79%) in the ultrasound-guided groups experienced at least a 50% reduction in VAS scores. There was no statistically significant difference between the two groups (P=1.0), and no complications were noted. We also did not find a significant difference in terms of number of patients with 30% or greater reduction (P=0.71) and changes in VAS pain scores (P=0.64). No complications were reported in either group. Conclusion In our study, there was no statistically significant difference between the landmark-based and ultrasound-guided groups in terms of a reduction in VAS pain scores, and no

  16. Surgical strategies for managing foraminal nerve sheath tumors: the emerging role of CyberKnife ablation

    PubMed Central

    Murovic, Judith A.; Charles Cho, S.

    2009-01-01

    Sixteen Stanford University Medical Center (SUMC) patients with foraminal nerve sheath tumors had charts reviewed. CyberKnife radiosurgery was innovative in management. Parameters were evaluated for 16 foraminal nerve sheath tumors undergoing surgery, some with CyberKnife. Three neurofibromas had associated neurofibromatosis type 1 (NF1). Eleven patients had one resection; others had CyberKnife after one (two) and two (three) operations. The malignant peripheral nerve sheath tumor (MPNST) had prior field-radiation and adds another case. Approaches included laminotomy and laminectomies with partial (three) or total (two) facetectomies/fusions. Two cases each had supraclavicular, lateral extracavitary, retroperitoneal and Wiltze and costotransversectomy/thoracotomy procedures. Two underwent a laminectomy/partial facetectomy, then CyberKnife. Pre-CyberKnife, one of two others had a laminectomy/partial facetectomy, then total facetectomy/fusion and the other, two supraclavicular approaches. The MPNST had a hemi-laminotomy then laminectomy/total facetectomy/fusion, followed by CyberKnife. Roots were preserved, except in two. Of 11 single-operation-peripheral nerve sheath tumors, the asymptomatic case remained stable, nine (92%) improved and one (9%) worsened. Examinations remained intact in three (27%) and improved in seven (64%). Two having a single operation then CyberKnife had improvement after both. Of two undergoing two operations, one had symptom resolution post-operatively, worsened 4 years post-CyberKnife then has remained unchanged after re-operation. The other such patient improved post-operatively, had no change after re-operation and improved post-CyberKnife. The MPNST had presentation improvement after the first operation, worsened and after the second surgery \\and CyberKnife, the patient expired from tumor spread. In conclusion, surgery is beneficial for pain relief and function preservation in foraminal nerve sheath tumors. Open surgery with Cyber

  17. Surgical strategies for managing foraminal nerve sheath tumors: the emerging role of CyberKnife ablation.

    PubMed

    Murovic, Judith A; Charles Cho, S; Park, Jon

    2010-02-01

    Sixteen Stanford University Medical Center (SUMC) patients with foraminal nerve sheath tumors had charts reviewed. CyberKnife radiosurgery was innovative in management. Parameters were evaluated for 16 foraminal nerve sheath tumors undergoing surgery, some with CyberKnife. Three neurofibromas had associated neurofibromatosis type 1 (NF1). Eleven patients had one resection; others had CyberKnife after one (two) and two (three) operations. The malignant peripheral nerve sheath tumor (MPNST) had prior field-radiation and adds another case. Approaches included laminotomy and laminectomies with partial (three) or total (two) facetectomies/fusions. Two cases each had supraclavicular, lateral extracavitary, retroperitoneal and Wiltze and costotransversectomy/thoracotomy procedures. Two underwent a laminectomy/partial facetectomy, then CyberKnife. Pre-CyberKnife, one of two others had a laminectomy/partial facetectomy, then total facetectomy/fusion and the other, two supraclavicular approaches. The MPNST had a hemi-laminotomy then laminectomy/total facetectomy/fusion, followed by CyberKnife. Roots were preserved, except in two. Of 11 single-operation-peripheral nerve sheath tumors, the asymptomatic case remained stable, nine (92%) improved and one (9%) worsened. Examinations remained intact in three (27%) and improved in seven (64%). Two having a single operation then CyberKnife had improvement after both. Of two undergoing two operations, one had symptom resolution post-operatively, worsened 4 years post-CyberKnife then has remained unchanged after re-operation. The other such patient improved post-operatively, had no change after re-operation and improved post-CyberKnife. The MPNST had presentation improvement after the first operation, worsened and after the second surgery \\and CyberKnife, the patient expired from tumor spread. In conclusion, surgery is beneficial for pain relief and function preservation in foraminal nerve sheath tumors. Open surgery with Cyber

  18. Evaluation of distal symmetric polyneuropathy: the role of autonomic testing, nerve biopsy, and skin biopsy (an evidence-based review).

    PubMed

    England, J D; Gronseth, G S; Franklin, G; Carter, G T; Kinsella, L J; Cohen, J A; Asbury, A K; Szigeti, K; Lupski, J R; Latov, N; Lewis, R A; Low, P A; Fisher, M A; Herrmann, D; Howard, J F; Lauria, G; Miller, R G; Polydefkis, M; Sumner, A J

    2009-01-01

    Distal symmetric polyneuropathy (DSP) is the most common variety of neuropathy. Since the evaluation of this disorder is not standardized, the available literature was reviewed to provide evidence-based guidelines regarding the role of autonomic testing, nerve biopsy, and skin biopsy for the assessment of polyneuropathy. A literature review using MEDLINE, EMBASE, Science Citation Index, and Current Contents was performed to identify the best evidence regarding the evaluation of polyneuropathy published between 1980 and March 2007. Articles were classified according to a four-tiered level of evidence scheme and recommendations were based on the level of evidence. (1) Autonomic testing may be considered in the evaluation of patients with polyneuropathy to document autonomic nervous system dysfunction (Level B). Such testing should be considered especially for the evaluation of suspected autonomic neuropathy (Level B) and distal small fiber sensory polyneuropathy (SFSN) (Level C). A battery of validated tests is recommended to achieve the highest diagnostic accuracy (Level B). (2) Nerve biopsy is generally accepted as useful in the evaluation of certain neuropathies as in patients with suspected amyloid neuropathy, mononeuropathy multiplex due to vasculitis, or with atypical forms of chronic inflammatory demyelinating polyneuropathy (CIDP). However, the literature is insufficient to provide a recommendation regarding when a nerve biopsy may be useful in the evaluation of DSP (Level U). (3) Skin biopsy is a validated technique for determining intraepidermal nerve fiber (IENF) density and may be considered for the diagnosis of DSP, particularly SFSN (Level C). There is a need for additional prospective studies to define more exact guidelines for the evaluation of polyneuropathy.

  19. Role of the Excitability Brake Potassium Current IKD in Cold Allodynia Induced by Chronic Peripheral Nerve Injury.

    PubMed

    González, Alejandro; Ugarte, Gonzalo; Restrepo, Carlos; Herrera, Gaspar; Piña, Ricardo; Gómez-Sánchez, José Antonio; Pertusa, María; Orio, Patricio; Madrid, Rodolfo

    2017-03-22

    Cold allodynia is a common symptom of neuropathic and inflammatory pain following peripheral nerve injury. The mechanisms underlying this disabling sensory alteration are not entirely understood. In primary somatosensory neurons, cold sensitivity is mainly determined by a functional counterbalance between cold-activated TRPM8 channels and Shaker-like Kv1.1-1.2 channels underlying the excitability brake current IKD Here we studied the role of IKD in damage-triggered painful hypersensitivity to innocuous cold. We found that cold allodynia induced by chronic constriction injury (CCI) of the sciatic nerve in mice, was related to both an increase in the proportion of cold-sensitive neurons (CSNs) in DRGs contributing to the sciatic nerve, and a decrease in their cold temperature threshold. IKD density was reduced in high-threshold CSNs from CCI mice compared with sham animals, with no differences in cold-induced TRPM8-dependent current density. The electrophysiological properties and neurochemical profile of CSNs revealed an increase of nociceptive-like phenotype among neurons from CCI animals compared with sham mice. These results were validated using a mathematical model of CSNs, including IKD and TRPM8, showing that a reduction in IKD current density shifts the thermal threshold to higher temperatures and that the reduction of this current induces cold sensitivity in former cold-insensitive neurons expressing low levels of TRPM8-like current. Together, our results suggest that cold allodynia is largely due to a functional downregulation of IKD in both high-threshold CSNs and in a subpopulation of polymodal nociceptors expressing TRPM8, providing a general molecular and neural mechanism for this sensory alteration.SIGNIFICANCE STATEMENT This paper unveils the critical role of the brake potassium current IKD in damage-triggered cold allodynia. Using a well-known form of nerve injury and combining behavioral analysis, calcium imaging, patch clamping, and pharmacological

  20. Role of CD44 in Malignant Peripheral Nerve Sheath Tumor Growth and Metastasis

    DTIC Science & Technology

    2003-09-01

    Malignant peripheral nerve sheath tumors ( MPNST ) are aggressive, difficult to treat tumors that occur in type I neurofibromatosis patients with an...survival rate. We previously found that MPNSTs overexpress the CD44 tranmembrane glycoprotein and that reducing CD44 expression partially inhibits MPNST ...depends on Src kinase and that Src kinase activity promotes MPNST invasion (Su et al., 2003a) . Furthermore, we show that MPNST cell invasion depends on

  1. Role of CD44 in Malignant Peripheral Nerve Sheath Tumor Growth and Metastasis

    DTIC Science & Technology

    2001-09-01

    Malignant peripheral nerve sheath tumors ( MPNST ) are aggressive, difficult to treat tumors that occur in type I neurofibromatosis patients with an...survival rate. We previously found that MPNSTs overexpress the CD44 tranmembrane glycoprotein and that reducing Cc44 expression inhibits MPNST cell...Src kinase. Furthermore, we show that MPNST cell invasion depends on an autocrine loop involving MCF, an MCF activating enzyme (MGFA), and c-Met, all of

  2. Remote arteriolar dilations caused by methacholine: a role for CGRP sensory nerves?

    PubMed

    Thengchaisri, Naris; Rivers, Richard J

    2005-08-01

    Remote vasodilation caused by arteriolar microapplication of acetylcholine cannot be completely attributed to passive cell-cell communication of a hyperpolarizing signal. The present study was undertaken to ascertain whether a neural component may be involved in the remote response. In the cheek pouch of anesthetized hamsters, methacholine (100 microM) was applied to the arteriole by micropipette for 5 s, and the arteriolar responses were measured at the site of application and at remote locations: 500 and 1,000 microm upstream from the application site. Superfusion with the local anesthetic bupivacaine attenuated a local dilatory response and abolished the conducted dilation response to methacholine. Localized micropipette application of bupivacaine 300 microm from the methacholine application site also attenuated the remote dilation but did not inhibit the local dilation. Blockade of neuromuscular transmission with botulinum neurotoxin A (1 U, 3 days), micropipette application of calcitonin gene-related peptide (CGRP) receptor inhibitor CGRP-(8-37) (10 microM) 300 microm upstream from the methacholine application site, and denervation of the CGRP sensory nerve by 2 days of capsaicin treatment reduced the conducted dilation response to methacholine but did not affect the local dilatory response. Together, these data support involvement of a TTX-insensitive nerve, specifically the CGRP containing nerve, in vascular communication. Understanding the effect of regulation of a novel neural network system on the vascular network may lead to a new insight into regulation of blood flow and intraorgan blood distribution.

  3. Antidromic effect of calcitonin gene-related peptide containing nerves on cerebral arteries in rats--a possible role of sensory nerves on cerebral circulatio.

    PubMed

    Asari, J; Suzuki, K; Matsumoto, M; Sasaki, T; Kodama, N

    2001-12-01

    It has generally been thought that the neurogenic control of cerebral circulation is decided mainly by the autonomic nervous system. Recent studies, however, indicate that sensory nerves rich in calcitonin gene-related peptide (CGRP) are also distributed on cerebral arteries. CGRP is one of neuropeptides that has strong vasodilative effect. This indicates that sensory nerves may antidromically dilate cerebral arteries mediated by CGRP. The aim of this study is to investigate the relationship between the CGRP containing nerves and cerebral circulation. Firstly, we developed a selective denervation model of CGRP containing nerves. The denervation was performed with intrathecal administration of capsaicin in rats. Secondly, we measured the change of regional cerebral blood flow (rCBF) during the occlusion of bilateral common carotid artery or systemic hypotension. CGRP immunoreactivity around cerebral arteries disappeared after capsaicin treatment. The rCBF during the occlusion of bilateral common carotid artery decreased more in the capsaicin group than in the control group. There was no significant difference in the changes of rCBF during systemic hypotension. These results showed that CGRP containing nerves would participate in the vascular response of cerebral arteries. It is likely that sensory nerves with CGRP should have antidromic effect on cerebral circulation.

  4. 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

  5. Postoperative Analgesia Using Psoas Sheath Block Versus Three-in-One Block in Anterior Cruciate Ligament Reconstruction

    DTIC Science & Technology

    1999-10-01

    were blocked and two cases where all nerves were blocked. Key Words: Regional Anesthesia; Lumbar Plexus Block, Postoperative Pain Management; Pre...and sciatic(Lumbar4-Sacral3). A "psoas sheath block" and a "three-in-one block" are two techniques used to block the lumbar plexus from which the...nerve blockade Operational definition. A regional anesthetic technique used to block transmission of the nerves of the lumbar plexus including the

  6. The Role of Nerve Growth Factor (NGF) and Its Precursor Forms in Oral Wound Healing

    PubMed Central

    Schenck, Karl; Schreurs, Olav; Hayashi, Katsuhiko; Helgeland, Kristen

    2017-01-01

    Nerve growth factor (NGF) and its different precursor forms are secreted into human saliva by salivary glands and are also produced by an array of cells in the tissues of the oral cavity. The major forms of NGF in human saliva are forms of pro-nerve growth factor (pro-NGF) and not mature NGF. The NGF receptors tropomyosin-related kinase A (TrkA) and p75 neurotrophin receptor (p75NTR) are widely expressed on cells in the soft tissues of the human oral cavity, including keratinocytes, endothelial cells, fibroblasts and leukocytes, and in ductal and acinar cells of all types of salivary glands. In vitro models show that NGF can contribute at most stages in the oral wound healing process: restitution, cell survival, apoptosis, cellular proliferation, inflammation, angiogenesis and tissue remodeling. NGF may therefore take part in the effective wound healing in the oral cavity that occurs with little scarring. As pro-NGF forms appear to be the major form of NGF in human saliva, efforts should be made to study its function, specifically in the process of wound healing. In addition, animal and clinical studies should be initiated to examine if topical application of pro-NGF or NGF can be a therapy for chronic oral ulcerations and wounds. PMID:28208669

  7. 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.

  8. The Role of Nerve Growth Factor (NGF) and Its Precursor Forms in Oral Wound Healing.

    PubMed

    Schenck, Karl; Schreurs, Olav; Hayashi, Katsuhiko; Helgeland, Kristen

    2017-02-11

    Nerve growth factor (NGF) and its different precursor forms are secreted into human saliva by salivary glands and are also produced by an array of cells in the tissues of the oral cavity. The major forms of NGF in human saliva are forms of pro-nerve growth factor (pro-NGF) and not mature NGF. The NGF receptors tropomyosin-related kinase A (TrkA) and p75 neurotrophin receptor (p75(NTR)) are widely expressed on cells in the soft tissues of the human oral cavity, including keratinocytes, endothelial cells, fibroblasts and leukocytes, and in ductal and acinar cells of all types of salivary glands. In vitro models show that NGF can contribute at most stages in the oral wound healing process: restitution, cell survival, apoptosis, cellular proliferation, inflammation, angiogenesis and tissue remodeling. NGF may therefore take part in the effective wound healing in the oral cavity that occurs with little scarring. As pro-NGF forms appear to be the major form of NGF in human saliva, efforts should be made to study its function, specifically in the process of wound healing. In addition, animal and clinical studies should be initiated to examine if topical application of pro-NGF or NGF can be a therapy for chronic oral ulcerations and wounds.

  9. 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

  10. Comparison of the Effect of Lidocaine versus a Lidocaine-Bupivacaine Combination in a Periprostatic Nerve Block Undergoing Transrectal Ultrasound-Guided Prostate Biopsy: A Double-Blind Randomized Controlled Trial

    PubMed Central

    Yilmaz, Ali H.; Ziypak, Elif; Ziypak, Tevfik; Aksoy, Mehmet; Adanur, Senol; Kocakgol, Hüseyin; Demirdogen, Saban O.; Polat, Ozkan

    2016-01-01

    Introduction To determine whether a combination of the long acting local anesthetic, bupivacaine, and lidocaine is better than lidocaine alone in the long-term pain control, which is a short-acting anesthetic. Materials and Methods In group 1, periprostatic nerve block was applied to both neurovascular areas with 2% lidocaine (5 ml) in an isotonic solution (5 ml). In group 2, the combination of 2% lidocaine (5 ml) and 5mg/ml bupivacaine (5 ml) was used for the PPNB. Results In the first 30 minutes the mean VAS scores of groups 1 and 2 were 2.1 ± 0.2 and 1.2 ± 0.1, respectively (p = 0.002). VAS scores of group II determined at 1, 2, 4, 6, and 8 hours after the biopsy were significantly lower since it was (p < 0.05). Conclusion While periprostatic nerve block for late phase pain control, applying a combination of a long-acting local anesthetic, such as bupivacaine, is effective in terms of pain control and patient comfort. PMID:27867334

  11. An Evaluation of 4% Prilocaine with 1:200,000 Epinephrine and 2% Mepivacaine with 1:20,000 Levonordefrin Compared with 2% Lidocaine with 1:100,000 Epinephrine for Inferior Alveolar Nerve Block

    PubMed Central

    Hinkley, Stewart A.; Reader, Al; Beck, Mike; Meyers, William J.

    1991-01-01

    The purpose of this study was to measure the degree of anesthesia obtained with 4% prilocaine with 1:200,000 epinephrine and 2% mepivacaine with 1:20,000 levonordefrin compared with 2% lidocaine with 1:100,000 epinephrine for inferior alveolar nerve block. Using a repeated measures design, 30 subjects randomly received an inferior alveolar injection using masked cartridges of each solution at three successive appointments. The first molar, first premolar, lateral incisor, and contralateral canine (control) were blindly tested with an Analytic Technology pulp tester at 3-min cycles for 50 min. Anesthetic success was defined as no subject response to the maximum output of the pulp tester (80 reading) within 16 min and maintenance of this reading for the remainder of the testing period. Although subjects felt numb subjectively, anesthetic success as defined here occurred in 46% to 57% of the molars, in 50% to 57% of the premolars, and in 21% to 36% of the lateral incisors. No statistically significant differences in onset, success, failure, or incidence were found among the solutions. We conclude that the three preparations are equivalent for inferior alveolar nerve block of 50-min duration. PMID:1814249

  12. Who Is at Risk for Heart Block?

    MedlinePlus

    ... degree heart block caused by an overly active vagus nerve. You have one vagus nerve on each side of your body. These nerves ... the way to your abdomen. Activity in the vagus nerve slows the heart rate. Rate This Content: NEXT >> ...

  13. Roles of blocking layer and anode bias in processes of impurity-band transition and transport for GaAs-based blocked-impurity-band detectors

    NASA Astrophysics Data System (ADS)

    Wang, Xiaodong; Wang, Bingbing; Chen, Xiaoyao; Chen, Yulu; Hou, Liwei; Xie, Wei; Pan, Ming

    2016-11-01

    Recently, GaAs-based BIB detector has attracted a lot of attention in the area of THz photovoltaic detection due to potential application values in security check and drug inspection. However, the physical mechanisms involving in carrier transition and transport are still unclear due to the poor material quality and immature processing technique. In this paper, the dark current and THz response characteristics have thus been numerically studied for GaAs-based blocked-impurity-band (BIB) detectors. The key parameters and physical models are constructed by simultaneously considering carrier freeze-out and impurity-band broadening effects. Roles of blocking layer and anode bias in processes of impurity-band transition and transport are intensively investigated, and the results can be well explained by numerical models. It is demonstrated that the effective electric field for the detector is only located in the absorbing layer, and can determine to a large extent the magnitude of the dark current and THz response. While the blocking layer not only can suppress dark current but also can attenuate responsivity due to its electric-field modulation effect.

  14. 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

  15. Role of renal sympathetic nerve activity in prenatal programming of hypertension.

    PubMed

    Baum, Michel

    2016-03-21

    Prenatal insults, such as maternal dietary protein deprivation and uteroplacental insufficiency, lead to small for gestational age (SGA) neonates. Epidemiological studies from many different parts of the world have shown that SGA neonates are at increased risk for hypertension and early death from cardiovascular disease as adults. Animal models, including prenatal administration of dexamethasone, uterine artery ligation and maternal dietary protein restriction, result in SGA neonates with fewer nephrons than controls. These models are discussed in this educational review, which provides evidence that prenatal insults lead to altered sodium transport in multiple nephron segments. The factors that could result in increased sodium transport are discussed, focusing on new information that there is increased renal sympathetic nerve activity that may be responsible for augmented renal tubular sodium transport. Renal denervation abrogates the hypertension in programmed rats but has no effect on control rats. Other potential factors that could cause hypertension in programmed rats, such as the renin-angiotensin system, are also discussed.

  16. Oxidative stress and nerve damage: Role in chemotherapy induced peripheral neuropathy☆

    PubMed Central

    Areti, Aparna; Yerra, Veera Ganesh; Naidu, VGM; Kumar, Ashutosh

    2014-01-01

    Peripheral neuropathy is a severe dose limiting toxicity associated with cancer chemotherapy. Ever since it was identified, the clear pathological mechanisms underlying chemotherapy induced peripheral neuropathy (CIPN) remain sparse and considerable involvement of oxidative stress and neuroinflammation has been realized recently. Despite the empirical use of antioxidants in the therapy of CIPN, the oxidative stress mediated neuronal damage in peripheral neuropathy is still debatable. The current review focuses on nerve damage due to oxidative stress and mitochondrial dysfunction as key pathogenic mechanisms involved in CIPN. Oxidative stress as a central mediator of apoptosis, neuroinflammation, metabolic disturbances and bioenergetic failure in neurons has been highlighted in this review along with a summary of research on dietary antioxidants and other nutraceuticals which have undergone prospective controlled clinical trials in patients undergoing chemotherapy. PMID:24494204

  17. 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.

  18. 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

  19. Protective Role of False Tendon in Subjects with Left Bundle Branch Block: A Virtual Population Study

    PubMed Central

    Lange, Matthias; Di Marco, Luigi Yuri; Lekadir, Karim; Lassila, Toni; Frangi, Alejandro F.

    2016-01-01

    False tendons (FTs) are fibrous or fibromuscular bands that can be found in both the normal and abnormal human heart in various anatomical forms depending on their attachment points, tissue types, and geometrical properties. While FTs are widely considered to affect the function of the heart, their specific roles remain largely unclear and unexplored. In this paper, we present an in silico study of the ventricular activation time of the human heart in the presence of FTs. This study presents the first computational model of the human heart that includes a FT, Purkinje network, and papillary muscles. Based on this model, we perform simulations to investigate the effect of different types of FTs on hearts with the electrical conduction abnormality of a left bundle branch block (LBBB). We employ a virtual population of 70 human hearts derived from a statistical atlas, and run a total of 560 simulations to assess ventricular activation time with different FT configurations. The obtained results indicate that, in the presence of a LBBB, the FT reduces the total activation time that is abnormally augmented due to a branch block, to such an extent that surgical implant of cardiac resynchronisation devices might not be recommended by international guidelines. Specifically, the simulation results show that FTs reduce the QRS duration at least 10 ms in 80% of hearts, and up to 45 ms for FTs connecting to the ventricular free wall, suggesting a significant reduction of cardiovascular mortality risk. In further simulation studies we show the reduction in the QRS duration is more sensitive to the shape of the heart then the size of the heart or the exact location of the FT. Finally, the model suggests that FTs may contribute to reducing the activation time difference between the left and right ventricles from 12 ms to 4 ms. We conclude that FTs may provide an alternative conduction pathway that compensates for the propagation delay caused by the LBBB. Further investigation is

  20. Role of block copolymer morphology on particle percolation of polymer nanocomposites.

    PubMed

    Feng, Yancong; Ning, Nanying; Zhao, Qiangli; Liu, Jun; Zhang, Liqun; Tian, Ming; Mi, Jianguo

    2014-11-07

    In this study, the effects of nanoparticle volume fraction, block stiffness, and diblock composition on the microstructure and electrical properties of composites are investigated using molecular dynamics simulation. It is shown that selective localization of conductive nanoparticles in a continuous block of diblock copolymer can dramatically reduce the percolation threshold. In the flexible-flexible copolymer systems with a relatively low particle loading, as the ratio of two blocks varies, one sees four kinds of phase structure: signal continuous, lamellar, co-continuous, and dispersed, corresponding to the order-disorder and continuity-dispersion transitions. In consideration of particle connectivity, the best electrical performance can be achieved with a special tri-continuous microstructure. While in the semi-flexible systems, the existence of rigid blocks can destroy the lamellar structure. If particles are located in the flexible block, a moderate stiffness of the rigid block can extensively enlarge the tri-continuous region, and high conductivity can be realized over a wide range of diblock compositions. If particles are located in the rigid block, however, high conductivity only emerges in a narrow composition range. In addition, the block should be prevented from becoming overstiff because this will cause direct particle aggregation.

  1. Role of Nerve Growth Factor (NGF) and miRNAs in Epithelial Ovarian Cancer

    PubMed Central

    Retamales-Ortega, Rocío; Oróstica, Lorena; Vera, Carolina; Cuevas, Paula; Hernández, Andrea; Hurtado, Iván; Vega, Margarita; Romero, Carmen

    2017-01-01

    Ovarian cancer is the eighth most common cancer in women worldwide, and epithelial ovarian cancer (EOC) represents 90% of cases. Nerve growth factor (NGF) and its high affinity receptor tyrosine kinase A receptor (TRKA) have been associated with the development of several types of cancer, including EOC; both NGF and TRKA levels are elevated in this pathology. EOC presents high angiogenesis and several molecules have been reported to induce this process. NGF increases angiogenesis through its TRKA receptor on endothelial cells, and by indirectly inducing vascular endothelial growth factor expression. Other molecules controlled by NGF include ciclooxigenase-2, disintegrin and metalloproteinase domain-containing protein 17 (ADAM17) and calreticulin (CRT), proteins involved in crucial processes needed for EOC progression. These molecules could be modified through microRNA regulation, which could be regulated by NGF. MicroRNAs are the widest family of non-coding RNAs; they bind to 3′-UTR of mRNAs to inhibit their translation, to deadenilate or to degraded them. In EOC, a deregulation in microRNA expression has been described, including alterations of miR-200 family, cluster-17-92, and miR-23b, among others. Since the NGF-microRNA relationship in pathologies has not been studied, this review proposes that some microRNAs could be associated with NGF/TRKA activation, modifying protein levels needed for EOC progression. PMID:28245631

  2. Pourfour Du Petit syndrome after interscalene block

    PubMed Central

    Santhosh, Mysore Chandramouli Basappji; Pai, Rohini B.; Rao, Raghavendra P.

    2013-01-01

    Interscalene block is commonly associated with reversible ipsilateral phrenic nerve block, recurrent laryngeal nerve block, and cervical sympathetic plexus block, presenting as Horner's syndrome. We report a very rare Pourfour Du Petit syndrome which has a clinical presentation opposite to that of Horner's syndrome in a 24-year-old male who was given interscalene block for open reduction and internal fixation of fracture upper third shaft of left humerus. PMID:23956726

  3. Pourfour Du Petit syndrome after interscalene block.

    PubMed

    Santhosh, Mysore Chandramouli Basappji; Pai, Rohini B; Rao, Raghavendra P

    2013-04-01

    Interscalene block is commonly associated with reversible ipsilateral phrenic nerve block, recurrent laryngeal nerve block, and cervical sympathetic plexus block, presenting as Horner's syndrome. We report a very rare Pourfour Du Petit syndrome which has a clinical presentation opposite to that of Horner's syndrome in a 24-year-old male who was given interscalene block for open reduction and internal fixation of fracture upper third shaft of left humerus.

  4. Roles of plate locking and block rotation in the tectonics of the Pacific Northwest

    NASA Astrophysics Data System (ADS)

    Ning, Zuoli

    The Pacific Northwest has potential for huge megathrust earthquakes. The influence of plate locking in the Cascadia subduction zone dominates crustal deformation off the shores of Washington and Oregon, but does not much affect areas far from the trench. The maximum principal strain rate epsilon 1 is -0.013 +/- 0.007 mustrain/yr in the Olympic Peninsula, 0.007 +/- 0.005 mustrain/yr in the Puget Sound, -0.005 +/- 0.005 mustrain/yr at Mt. Rainier, -0.004 +/- 0.005 mustrain/yr along the northern Oregon coast, and 0.011 +/- 0.006 mustrain/yr in central Oregon. The minimum principal strain rate epsilon2 is -0.083 +/- 0.008 mustrain/yr N56°E in the Olympic Peninsula, -0.034 +/- 0.007 mustrain/yr N63°E in the Puget Sound, -0.020 +/- 0.006 mustrain/yr N53°E at Mt. Rainier, -0.051 +/- 0.014 mustrain/yr N85°E along the northern Oregon coast, and -0.010 +/- 0.006 mustrain/yr N71°E in central Oregon. A new model of plate locking on the Cascadia subduction zone is similar to a model (1997). The uncertainty of the widths of the locked and transition zone in the model is about 25km--40km. Guided by computed site velocities, seismicity patterns, heat flow, volcanic data, and geological structures, we find it is necessary to divide the crust in the Pacific Northwest into separate moving blocks. We have analyzed a model in which the Oregon block is separated from the Washington block at latitude 46°. The Washington block has been further divided into 5-subblocks, three in the forearc and two in eastern Washington. We remove contributions of JDF plate locking from the site velocity field and determine a rotation pole and a strain rate for each sub-block. We conclude that Juan de Fuca plate locking has little direct effect on crustal earthquake occurrence in the Pacific Northwest (except for periodic megathrust earthquakes). In the Oregon block, plate locking and rigid block rotation are sufficient to explain GPS observations and the lower rate of seismicity in Oregon. The

  5. 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.

  6. Cerebral sympathetic nerve activity has a major regulatory role in the cerebral circulation in REM sleep.

    PubMed

    Cassaglia, Priscila A; Griffiths, Robert I; Walker, Adrian M

    2009-04-01

    Sympathetic nerve activity (SNA) in neurons projecting to skeletal muscle blood vessels increases during rapid-eye-movement (REM) sleep, substantially exceeding SNA of non-REM (NREM) sleep and quiet wakefulness (QW). Similar SNA increases to cerebral blood vessels may regulate the cerebral circulation in REM sleep, but this is unknown. We hypothesized that cerebral SNA increases during phasic REM sleep, constricting cerebral vessels as a protective mechanism against cerebral hyperperfusion during the large arterial pressure surges that characterize this sleep state. We tested this hypothesis using a newly developed model to continuously record SNA in the superior cervical ganglion (SCG) before, during, and after arterial pressure surges occurring during REM in spontaneously sleeping lambs. Arterial pressure (AP), intracranial pressure (ICP), cerebral blood flow (CBF), cerebral vascular resistance [CVR = (AP - ICP)/CBF], and SNA from the SCG were recorded in lambs (n = 5) undergoing spontaneous sleep-wake cycles. In REM sleep, CBF was greatest (REM > QW = NREM, P < 0.05) and CVR was least (REM < QW = NREM, P < 0.05). SNA in the SCG did not change from QW to NREM sleep but increased during tonic REM sleep, with a further increase during phasic REM sleep (phasic REM > tonic REM > QW = NREM, P < 0.05). Coherent averaging revealed that SNA increases preceded AP surges in phasic REM sleep by 12 s (P < 0.05). We report the first recordings of cerebral SNA during natural sleep-wake cycles. SNA increases markedly during tonic REM sleep, and further in phasic REM sleep. As SNA increases precede AP surges, they may serve to protect the brain against potentially damaging intravascular pressure changes or hyperperfusion in REM sleep.

  7. Epinephrine administration increases neural impulses propagated along the vagus nerve: Role of peripheral beta-adrenergic receptors.

    PubMed

    Miyashita, T; Williams, C L

    2006-03-01

    A significant number of animal and human studies demonstrate that memories for new experiences are encoded more effectively under environmental or laboratory conditions which elevate peripheral concentrations of the hormone epinephrine and in turn, induce emotional arousal. Although this phenomenon has been replicated across several learning paradigms, understanding of how this arousal related hormone affects memory processing remains obscure because epinephrine does not freely enter into the central circulation to produce any direct effects on the brain. This study examined whether epinephrine's actions on the CNS may be mediated by the initial activation of peripheral vagal fibers that project to the brain. The vagus was selected as a candidate for this role since it is densely embedded with beta-adrenergic receptors and the peripheral endings of this nerve innervate a broad spectrum of sensory organs that are directly affected by epinephrine release. Electrophysiological recordings of cervical vagal activity was measured over 110 min in urethane-anesthetized Sprague-Dawley rats given saline, epinephrine (0.3 mg/kg), the peripherally acting beta-adrenergic antagonist sotalol (2.0 mg/kg), or a combination of sotalol followed 15 min later by an injection of epinephrine. Epinephrine produced a significant increase in vagal nerve firing 10 min post-injection (p < .05) relative to controls and neural impulses recorded from the vagus remained significantly elevated for the remaining 55 min collection period. The excitatory actions of epinephrine were not observed in groups given an identical dose of the hormone after peripheral beta-adrenergic receptor blockade with sotalol. These findings demonstrate that neural discharge in vagal afferent fibers is increased by elevations in peripheral concentrations of epinephrine and the significance of these findings in understanding how epinephrine modulates brain limbic structures to encode and store new information into memory

  8. 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

  9. 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.

  10. A permissive role for the vagus nerves in the genesis of antro-antral reflexes in the anaesthetized ferret.

    PubMed Central

    Grundy, D; Hutson, D; Scratcherd, T

    1986-01-01

    1. The role of the vagus nerves in the genesis of antro-antral reflexes was investigated in the urethane-anaesthetized, splanchnectomized ferret. 2. Antral distension stimulated antral contractions with a threshold volume of 3.5 +/- 0.9 ml (corresponding to an intra-antral pressure of 0.27 +/- 0.11 kPa) by a vagal-dependent mechanism as indicated by the attenuated response seen during vagal blockade by cooling. Atropine (1 mg/kg) abolished the antral response to distension. 3. In vagotomized animals, close arterial infusions of acetylcholine at a dose sufficient to return antral motility to basal levels led to the reappearance of the reflex. Low-frequency electrical stimulation of the preganglionic vagal neurones had a similar effect. These effects were also abolished by atropine (1 mg/kg). 4. Hexamethonium (10-25 mg/kg) suppressed the potentiating effect of acetylcholine, indicating a ganglionic site of action. The attenuated response to antral distension seen in vagotomized animals in the absence of exogenous acetylcholine or electrical vagal stimulation was not sensitive to hexamethonium but abolished by atropine (1 mg/kg). 5. The results are consistent with the vagus performing a permissive role in the genesis of antro-antral reflexes mediated through local enteric pathways. PMID:2887649

  11. Role of Late Sodium Channel Current Block in the Management of Atrial Fibrillation

    PubMed Central

    Antzelevitch, Charles

    2012-01-01

    The anti-arrhythmic efficacy of the late sodium channel current (late INa) inhibition has been convincingly demonstrated in the ventricles, particularly under conditions of prolonged ventricular repolarization. The value of late INa block in the setting of atrial fibrillation (AF) remains poorly investigated. All sodium channel blockers inhibit both peak and late INa and are generally more potent in inhibiting late vs. early INa. Selective late INa block does not prolong the effective refractory period (ERP), a feature common to practically all anti-AF agents. Although the late INa blocker ranolazine has been shown to be effective in suppression of AF, it is noteworthy that at concentrations at which it blocks late INa in the ventricles, it also potently blocks peak INa in the atria, thus causing rate-dependent prolongation of ERP due to development of post-repolarization refractoriness. Late INa inhibition in atria is thought to suppress intracellular calcium (Cai)-mediated triggered activity, secondary to a reduction in intracellular sodium (Nai). However, agents that block late INa (ranolazine, amiodarone, vernakalant, etc) are also potent atrial-selective peak INa blockers, so that the reduction of Nai loading in atrial cells by these agents can be in large part due to the block of peak INa. The impact of late INa inhibition is reduced by the abbreviation of the action potential that occurs in AF patients secondary to electrical remodeling. It stands to reason that selective late INa block may contribute more to inhibition of Cai-mediated triggered activity responsible for initiation of AF in clinical pathologies associated with a prolonged atrial APD (such as long QT syndrome). Additional studies are clearly needed to test this hypothesis. PMID:23108433

  12. 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 Review Date 6/1/2015 ...

  13. Active tectonics in Southern Alaska and the role of the Yakutat block constrained by GPS measurements

    NASA Astrophysics Data System (ADS)

    Elliott, Julie

    2011-12-01

    GPS data from southern Alaska and the northern Canadian Cordillera have helped redefine the region's tectonic landscape. Instead of a comparatively simple interaction between the Pacific and North American plates, with relative motion accommodated on a single boundary fault, the margin is made up of a number of small blocks and deformation zones with relative motion distributed across a variety of structures. Much of this complexity can be attributed to the Yakutat block, an allochthonous terrane that has been colliding with southern Alaska since the Miocene. This thesis presents GPS data from across the region and uses it to constrain a tectonic model for the Yakutat block collision and its effects on southern Alaska and eastern Canada. The Yakutat block itself moves NNW at a rate of 50 mm/yr. Along its eastern edge, the Yakutat block is fragmenting into small crustal slivers. Part of the strain from the collision is transferred east of the Fairweather -- Queen Charlotte fault system, causing the region inboard of the Fairweather fault to undergo a distinct clockwise rotation into the northern Canadian Cordillera. About 5% of the relative motion is transferred even further east, causing small northeasterly motions well into the northern Cordillera. Further north, the GPS data and model results indicate that the current deformation front between the Yakutat block and southern Alaska runs along the western side of the Malaspina Glacier. The majority of the ˜37 mm/yr of relative convergence is accommodated along a narrow band of thrust faults concentrated in the southeastern part of the St. Elias orogen. Near the Bering Glacier, the tectonic regime abruptly changes as crustal thrust faults give way to subduction of the Yakutat block beneath the western St. Elias orogen and Prince William Sound. This change aligns with the Gulf of Alaska shear zone, implying that the Pacific plate is fragmenting in response to the Yakutat collision. The Bering Glacier region is

  14. Role of solution structure in self-assembly of conjugated block copolymer thin films

    DOE PAGES

    Brady, Michael A.; Ku, Sung -Yu; Perez, Louis A.; ...

    2016-10-24

    Conjugated block copolymers provide a pathway to achieve thermally stable nanostructured thin films for organic solar cells. We characterized the structural evolution of poly(3-hexylthiophene)-block-poly(diketopyrrolopyrrole–terthiophene) (P3HT-b-DPPT-T) from solution to nanostructured thin films. Aggregation of the DPPT-T block of P3HT-b-DPPT-T was found in solution by small-angle X-ray scattering with the P3HT block remaining well-solvated. The nanostructure in thin films was determined using a combination of wide and small-angle X-ray scattering techniques as a function of processing conditions. The structure in solution controlled the initial nanostructure in spin-cast thin films, allowing subsequent thermal annealing processes to further improve the ordering. In contrast tomore » the results for thin films, nanostructural ordering was not observed in the bulk samples by small-angle X-ray scattering. Finally, these results suggest the importance of controlling solvent induced aggregation in forming nanostructured thin films of conjugated block copolymers.« less

  15. Role of solution structure in self-assembly of conjugated block copolymer thin films

    SciTech Connect

    Brady, Michael A.; Ku, Sung -Yu; Perez, Louis A.; Cochran, Justin E.; Schmidt, Kristin; Weiss, Thomas M.; Toney, Michael F.; Ade, Harald; Hexemer, Alexander; Wang, Cheng; Hawker, Craig J.; Kramer, Edward J.; Chabinyc, Michael L.

    2016-10-24

    Conjugated block copolymers provide a pathway to achieve thermally stable nanostructured thin films for organic solar cells. We characterized the structural evolution of poly(3-hexylthiophene)-block-poly(diketopyrrolopyrrole–terthiophene) (P3HT-b-DPPT-T) from solution to nanostructured thin films. Aggregation of the DPPT-T block of P3HT-b-DPPT-T was found in solution by small-angle X-ray scattering with the P3HT block remaining well-solvated. The nanostructure in thin films was determined using a combination of wide and small-angle X-ray scattering techniques as a function of processing conditions. The structure in solution controlled the initial nanostructure in spin-cast thin films, allowing subsequent thermal annealing processes to further improve the ordering. In contrast to the results for thin films, nanostructural ordering was not observed in the bulk samples by small-angle X-ray scattering. Finally, these results suggest the importance of controlling solvent induced aggregation in forming nanostructured thin films of conjugated block copolymers.

  16. 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

  17. The Role of Peripheral Nerve Function in Age-Related Bone Loss and Changes in Bone Adaptation

    DTIC Science & Technology

    2015-12-01

    mice, despite a considerable and sustained decrease in sensory nerve activity. Physiological adaptations during development may allow mice to...Department of Anatomy, Physiology , & Cell Biology, USA Abstract Objectives: The present study sought to determine the effects of decreased peripheral...differences in bone parameters in capsaicin-treated mice, despite a considerable and sustained decrease in sensory nerve activity. Physiological

  18. Binding of amphiphilic and triphilic block copolymers to lipid model membranes: the role of perfluorinated moieties.

    PubMed

    Schwieger, Christian; Achilles, Anja; Scholz, Sven; Rüger, Jan; Bacia, Kirsten; Saalwaechter, Kay; Kressler, Jörg; Blume, Alfred

    2014-09-07

    A novel class of symmetric amphi- and triphilic (hydrophilic, lipophilic, fluorophilic) block copolymers has been investigated with respect to their interactions with lipid membranes. The amphiphilic triblock copolymer has the structure PGMA(20)-PPO(34)-PGMA(20) (GP) and it becomes triphilic after attaching perfluoroalkyl moieties (F9) to either end which leads to F(9)-PGMA(20)-PPO(34)-PGMA(20)-F(9) (F-GP). The hydrophobic poly(propylene oxide) (PPO) block is sufficiently long to span a lipid bilayer. The poly(glycerol monomethacrylate) (PGMA) blocks have a high propensity for hydrogen bonding. The hydrophobic and lipophobic perfluoroalkyl moieties have the tendency to phase segregate in aqueous as well as in hydrocarbon environments. We performed differential scanning calorimetry (DSC) measurements on polymer bound lipid vesicles under systematic variation of the bilayer thickness, the nature of the lipid headgroup, and the polymer concentration. The vesicles were composed of phosphatidylcholines (DMPC, DPPC, DAPC, DSPC) or phosphatidylethanolamines (DMPE, DPPE, POPE). We showed that GP as well as F-GP binding have membrane stabilizing and destabilizing components. PPO and F9 blocks insert into the hydrophobic part of the membrane concomitantly with PGMA block adsorption to the lipid headgroup layer. The F9 chains act as additional membrane anchors. The insertion of the PPO blocks of both GP and F-GP could be proven by 2D-NOESY NMR spectroscopy. By fluorescence microscopy we show that F-GP binding increases the porosity of POPC giant unilamellar vesicles (GUVs), allowing the influx of water soluble dyes as well as the translocation of the complete triphilic polymer and its accumulation at the GUV surface. These results open a new route for the rational design of membrane systems with specific properties.

  19. 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

  20. Active Tectonics of Southern Alaska and the Role of the Yakutat Block Constrained by GPS

    NASA Astrophysics Data System (ADS)

    Elliott, J.; Freymueller, J. T.; Larsen, C. F.

    2011-12-01

    GPS data from southern Alaska and the northern Canadian Cordillera have helped redefine the region's tectonic landscape. Instead of a comparatively simple interaction between the Pacific and North American plates, with relative motion accommodated on a single boundary fault, the margin is made up of a number of small blocks and deformation zones with relative motion distributed across a variety of structures. Much of this complexity can be attributed to the Yakutat block, an allochthonous terrane that has been colliding with southern Alaska since the Miocene. We present GPS data from across the region and use it to constrain a tectonic model for the Yakutat block collision and its effects on southern Alaska and eastern Canada. According to our model, the Yakutat block itself moves NNW at a rate of 50 mm/yr. Along its eastern edge, the Yakutat block is fragmenting into small crustal slivers. Part of the strain from the collision is transferred east of the Fairweather - Queen Charlotte fault system, causing the region inboard of the Fairweather fault to undergo a distinct clockwise rotation into the northern Canadian Cordillera. About 5% of the relative motion is transferred even further east, causing small northeasterly motions well into the northern Cordillera. Further north, the GPS data and model results indicate that the current deformation front between the Yakutat block and southern Alaska runs along the western side of the Malaspina Glacier. The majority of the ~37 mm/yr of relative convergence is accommodated along a narrow band of thrust faults concentrated in the southeastern part of the St. Elias orogen. Near the Bering Glacier, the tectonic regime abruptly changes as crustal thrust faults give way to subduction of the Yakutat block beneath the western St. Elias orogen and Prince William Sound. This change aligns with the Gulf of Alaska shear zone, implying that the Pacific plate may be fragmenting in response to the Yakutat collision. From the Bering

  1. Role for NGF in augmented sympathetic nerve response to activation of mechanically and metabolically sensitive muscle afferents in rats with femoral artery occlusion.

    PubMed

    Lu, Jian; Xing, Jihong; Li, Jianhua

    2012-10-15

    Arterial blood pressure and heart rate responses to static contraction of the hindlimb muscles are greater in rats whose femoral arteries were previously ligated than in control rats. Also, the prior findings demonstrate that nerve growth factor (NGF) is increased in sensory neurons-dorsal root ganglion (DRG) neurons of occluded rats. However, the role for endogenous NGF in engagement of the augmented sympathetic and pressor responses to stimulation of mechanically and/or metabolically sensitive muscle afferent nerves during static contraction after femoral artery ligation has not been specifically determined. In the present study, both afferent nerves and either of them were activated by muscle contraction, passive tendon stretch, and arterial injection of lactic acid into the hindlimb muscles. Data showed that femoral occlusion-augmented blood pressure response to contraction was significantly attenuated by a prior administration of the NGF antibody (NGF-Ab) into the hindlimb muscles. The effects of NGF neutralization were not seen when the sympathetic nerve and pressor responses were evoked by stimulation of mechanically sensitive muscle afferent nerves with tendon stretch in occluded rats. In addition, chemically sensitive muscle afferent nerves were stimulated by lactic acid injected into arterial blood supply of the hindlimb muscles after the prior NGF-Ab, demonstrating that the reflex muscle responses to lactic acid were significantly attenuated. The results of this study further showed that NGF-Ab attenuated an increase in acid-sensing ion channel subtype 3 (ASIC3) of DRG in occluded rats. Moreover, immunohistochemistry was employed to examine the number of C-fiber and A-fiber DRG neurons. The data showed that distribution of DRG neurons with different thin fiber phenotypes was not notably altered when NGF was infused into the hindlimb muscles. However, NGF increased expression of ASIC3 in DRG neurons with C-fiber but not A-fiber. Overall, these data

  2. Role of endothelin-A receptors in optic nerve head red cell flux regulation during isometric exercise in healthy humans.

    PubMed

    Boltz, Agnes; Schmidl, Doreen; Werkmeister, René M; Lasta, Michael; Kaya, Semira; Palkovits, Stefan; Told, Reinhard; Frantal, Sophie; Garhöfer, Gerhard; Schmetterer, Leopold

    2013-01-01

    Endothelin-1 (ET-1) is an important regulator of vascular tone in the eye. It appears to play a role in ocular disease because of its strong vasoconstrictor action, its role in intraocular pressure homeostasis, and its neurotoxic potential. We have previously shown that ET-1 is involved in choroidal red cell flux (RCF) regulation during isometric exercise in healthy humans. In the present study we hypothesized that ET-1 also plays a role in optic nerve head (ONH) RCF regulation during isometric exercise. To test this hypothesis, we performed a randomized, double-masked, placebo-controlled, two-way crossover study in 15 healthy volunteers. Subjects were randomized to receive intravenous infusions of the specific endothelin type A receptor antagonist BQ-123 and placebo on two different study days. During these infusion periods, subjects performed squatting for 6 min to increase ocular perfusion pressure (OPP). ONH RCF was assessed with laser-Doppler flowmetry, and OPP was calculated from mean arterial pressure and intraocular pressure. BQ-123 did not change OPP or ONH RCF at baseline. The relative increase in OPP during isometric exercise was comparable between both groups (between 84 and 88%, P = 0.76 between groups; P < 0.001 vs. baseline). Isometric exercise increased ONH RCF during placebo and BQ-123, but the increase was more pronounced when the endothelin type-A receptor antagonist was administered (placebo, 27.3 ± 5.4%; and BQ-123, 39.2 ± 4.4%; P = 0.007 between groups). The present data indicate that ET-1 regulates red cell flux in the ONH beyond the autoregulatory range.

  3. Stimulation of phrenic nerve activity by an acetylcholine releasing drug: 4-aminopyridine.

    PubMed

    Folgering, H; Rutten, J; Agoston, S

    1979-03-16

    The effect of the acetylcholine releaser 4-aminopyridine on ventilation was studied by recording and quantifying the efferent phrenic nerve activity in 40 paralysed and vagotomized cats; with arterial Po2, PCO2 and pH kept constant. 4-Aminopyridine, given intravenously or in the vertebral artery, stimulates the phrenic nerve activity in a dose dependent manner. The stimulatory effects of 4-aminopyridine on the phrenic nerve activity could be abolished completely by administration of high doses of atropine. We conclude that 4-aminopyridine, which is used clinically for the reversal of a neuromuscular block, stimulates the phrenic nerve activity. Since the role of cholinergic mechanisms in the central chemoreception has been well established, the effect on the phrenic nerve activity is most probably by an increased release of acetylcholine at the site of the central chemoreceptors.

  4. Interaction of poloxamine block copolymers with lipid membranes: Role of copolymer structure and membrane cholesterol content.

    PubMed

    Sandez-Macho, Isabel; Casas, Matilde; Lage, Emilio V; Rial-Hermida, M Isabel; Concheiro, Angel; Alvarez-Lorenzo, Carmen

    2015-09-01

    Interactions of X-shaped poly(ethylene oxide)-poly(propylene oxide) (PEO-PPO) block copolymers with cell membranes were investigated recording the π-A isotherms of monolayer systems of dipalmitoylphosphatidylcholine (DPPC):cholesterol 100:0; 80:20 and 60:40 mol ratio and evaluating the capability of the copolymers to trigger haemolysis or to protect from haemolytic agents. Four varieties of poloxamine (Tetronic 904, 908, 1107 and 1307) were chosen in order to cover a wide range of EO and PO units contents and molecular weights, and compared to a variety of poloxamer (Pluronic P85). The π-A isotherms revealed that the greater the content in cholesterol, the stronger the interaction of the block copolymers with the lipids monolayer. The interactions were particularly relevant at low pressures and low lipid proportions, mimicking the conditions of damaged membranes. Relatively hydrophobic copolymers bearing short PEO blocks (e.g., T904 and P85) intercalated among the lipids expanding the surface area (ΔGexc) but not effectively sealing the pores. These varieties showed haemolytic behavior. Oppositely, highly hydrophilic copolymers bearing long PEO blocks (e.g., T908, T1107 and T1307) caused membrane contraction and outer leaflet sealing due to strong interactions of PEO with cholesterol and diamine core with phospholipids. These later varieties were not haemolytic and exerted a certain protective effect against spontaneous haemolysis for both intact erythrocytes and cholesterol-depleted erythrocytes.

  5. Role of nerve growth factor and its TRKA receptor in normal ovarian and epithelial ovarian cancer angiogenesis.

    PubMed

    Vera, Carolina; Tapia, Verónica; Vega, Margarita; Romero, Carmen

    2014-08-10

    In normal ovarian function a controlled angiogenesis is essential. Several growth factors are involved in this process, such as the vascular endothelial growth factor (VEGF) and nerve growth factor (NGF). The angiogenesis process in the normal ovary is a tightly controlled process that occurs in each ovarian cycle. Also, angiogenesis is critical for ovarian cancer development and it is responsible for tumor spread, metastasis and its peritoneal dissemination. Ovarian cancer is the fifth leading cause of cancer death in women and it is distinguished as the most lethal gynecologic cancer. In recent years angiogenesis has been given considerable attention in order to identify targets for developing effective anti-tumor therapies. Several molecules have been reported to promote angiogenesis, such as platelet-derived growth factor (PDGF) and its receptors, the angiopoietin/Tie ligand/receptor system and fibroblast growth factor (FGF). Primarily, VEGF has been identified to play key roles in driving angiogenesis. The above-mentioned molecules are candidate drug targets. Used in combination with other treatments, anti-angiogenic therapies have managed to reduce disease progression. The present review is focused in NGF and its high affinity receptor tyrosine kinase A (TRKA). The expression of VEGF, proliferation and the angiogenesis process in ovarian cancer is importantly induced by NGF, among other molecules.

  6. Vagus Nerve Stimulation.

    PubMed

    Howland, Robert H

    2014-06-01

    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.

  7. 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

  8. 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

  9. Common peroneal nerve dysfunction

    MedlinePlus

    Neuropathy - common peroneal nerve; Peroneal nerve injury; Peroneal nerve palsy ... type of peripheral neuropathy (damage to nerves outside the brain ... nerve injuries. Damage to the nerve disrupts the myelin sheath ...

  10. 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.

  11. The Role of Task-Specific Response Strategies in Blocked-Cyclic Naming.

    PubMed

    Belke, Eva

    2016-01-01

    In word retrieval, speakers need to select a lexical entry among several co-activated candidates for lexicalization. How a target entry is selected is a matter of ongoing debate. Semantic context effects on naming times, as seen in the blocked-cyclic naming paradigm, are of specific interest to this debate. In the standard version of this paradigm, participants name lists of objects compiled from several repetitions (cycles) of a small set of semantically related objects (homogeneous context) or unrelated objects (heterogeneous context). In the first cycle, participants typically show either no context effect or semantic facilitation. From cycle two onward, they display a stable semantic interference effect that does not increase over cycles. In this review, I demonstrate that the early semantic facilitation effect is only observed consistently in studies that present homogeneous and heterogeneous lists in a blocked fashion. With this design, participants can easily pick up on the categorical relatedness of the items in semantically related contexts and apply this knowledge strategically. In principle, such response strategies can be easily tied in with existing models of lexical selection, but they are incompatible with accounts of semantic context effects that take the semantic facilitation effect in cycle 1 to be a consequence of processes inherent to the lexicalization process. Users of the blocked-cyclic naming paradigm should review their experimental designs carefully regarding potential response strategies. Once these are taken into account, the paradigm can be used to study lexical-semantic encoding in different populations of healthy and also impaired speakers.

  12. The Role of Peripheral Nerve Function in Age-Related Bone Loss and Changes in Bone Adaptation

    DTIC Science & Technology

    2014-10-01

    and peripheral neuropathy has been identified as an in- dependent predictor of low bone mass in the affected limb of diabetic subjects26. Despite...radial and sural nerves. J Neurol Neurosurg Psychiatry 1968;31:464-70. 9. Swallow M. Fibre size and content of the anterior tibial nerve of the foot ...Rix M, Andreassen H, Eskildsen P. Impact of peripheral neuropathy on bone density in patients with type 1 dia- betes. Diabetes Care 1999;22:827-31

  13. Lidocaine versus ropivacaine for postoperative continuous paravertebral nerve blocks in patients undergoing laparoscopic bowel surgery: a randomized, controlled, double-blinded, pilot study

    PubMed Central

    Ghisi, Daniela; Fanelli, Andrea; Jouguelet-Lacoste, Julie; La Colla, Luca; Auroux, Anne-Sophie; Chelly, Jacques E

    2015-01-01

    Background and objectives Lidocaine could provide many advantages in continuous regional anesthesia techniques, including faster onset, greater titratability, and lower cost than long-acting local anesthetics. This prospective, randomized, double-blinded, pilot study is therefore intended to compare lidocaine to ropivacaine in bilateral continuous paravertebral blocks using a multimodal approach for postoperative pain management following laparoscopic bowel surgery. Methods Thirty-five ASA I–III consecutive patients undergoing elective laparoscopic bowel surgery and bilateral thoracic paravertebral continuous blocks were analyzed: bilateral thoracic paravertebral infusions of ropivacaine 0.2% (Group Ropi, n=18) or lidocaine 0.25% (Group Lido, n=17) were started at 7 mL/h in the postanesthesia care unit. For each patient, we collected numerical rating scores (NRS) for pain at rest and during movement at baseline, at postanesthesia care unit discharge, at 24 hours and 48 hours after the end of surgery, as well as hydromorphone patient-controlled analgesia requirements, local anesthetic consumption, side effects, postoperative complications, and functional outcomes. Results No effect of group distribution on NRS scores for pain at rest or at movement (P=0.823 and P=0.146), nor on hydromorphone (P=0.635) or local anesthetic consumption (P=0.063) was demonstrated at any analyzed time point. Hospital length of stay and spontaneous ambulation were comparable between groups (P=0.636 and P=0.148). In the context of a multimodal approach, the two drugs showed comparable safety profiles. Discussion Lidocaine 0.25% and ropivacaine 0.2% provided similar analgesic profiles after elective abdominal surgeries, without any difference in terms of functional outcomes. The easier titratability of lidocaine together with its lower cost induced our clinical practice to definitely switch from ropivacaine to lidocaine for postoperative bilateral paravertebral continuous infusions. PMID

  14. 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

  15. The Role of Task-Specific Response Strategies in Blocked-Cyclic Naming

    PubMed Central

    Belke, Eva

    2017-01-01

    In word retrieval, speakers need to select a lexical entry among several co-activated candidates for lexicalization. How a target entry is selected is a matter of ongoing debate. Semantic context effects on naming times, as seen in the blocked-cyclic naming paradigm, are of specific interest to this debate. In the standard version of this paradigm, participants name lists of objects compiled from several repetitions (cycles) of a small set of semantically related objects (homogeneous context) or unrelated objects (heterogeneous context). In the first cycle, participants typically show either no context effect or semantic facilitation. From cycle two onward, they display a stable semantic interference effect that does not increase over cycles. In this review, I demonstrate that the early semantic facilitation effect is only observed consistently in studies that present homogeneous and heterogeneous lists in a blocked fashion. With this design, participants can easily pick up on the categorical relatedness of the items in semantically related contexts and apply this knowledge strategically. In principle, such response strategies can be easily tied in with existing models of lexical selection, but they are incompatible with accounts of semantic context effects that take the semantic facilitation effect in cycle 1 to be a consequence of processes inherent to the lexicalization process. Users of the blocked-cyclic naming paradigm should review their experimental designs carefully regarding potential response strategies. Once these are taken into account, the paradigm can be used to study lexical-semantic encoding in different populations of healthy and also impaired speakers. PMID:28119637

  16. Sudden cardiac death and the potential role of beta-adrenoceptor-blocking drugs.

    PubMed Central

    Rajman, I.; Kendall, M. J.

    1993-01-01

    Sudden cardiac death is a major health problem in the industrially developed countries. The risk of sudden cardiac death may be reduced by early detection of coronary heart disease, elimination of the risk factors, treatment of the ischaemia in patients known to have coronary heart disease and suppression of ventricular arrhythmias. Of all the therapeutic measures currently available to reduce the risk of sudden cardiac death, beta-adrenoceptor-blocking drugs (beta blockers) appear to be the most effective. In this paper their actions are reviewed and evidence for their efficacy is presented. PMID:7907178

  17. Role of Kabat rehabilitation in facial nerve palsy: a randomised study on severe cases of Bell's palsy.

    PubMed

    Monini, S; Iacolucci, C M; Di Traglia, M; Lazzarino, A I; Barbara, M

    2016-08-01

    The treatment of Bell's palsy (BP), based on steroids and/or antiviral drugs, may still leave a certain percentage of affected subjects with disfiguring sequelae due to incomplete recovery. The different procedures of physical rehabilitation have not been demonstrated to play a favourable role in this disorder. The aim of the present study was to compare functional outcomes in severe cases of Bell's palsy when treated by steroids alone or by steroids accompanied by Kabat physical rehabilitation. This prospective study included 94 subjects who showed sudden facial nerve (FN) palsy with House-Brackmann grade IV or V and who were divided into two groups on the basis of the therapeutic approach: one group (a) was treated by steroids, and the other (b) received steroids in combination with physical rehabilitation. Medical treatment consisted in administration of steroids at a dosage of 60 mg per day for 15 days; physical rehabilitative treatment consisted in proprioceptive neuromuscular facilitation according to Kabat, and was administered to one of the two groups of subjects. Recovery rate, degree of recovery and time for recovery were compared between the two groups using the Mann-Whitney and univariate logistic regression statistical tests (Ward test). Kabat patients (group b) had about 20 times the odds of improving by three HB grades or more (OR = 17.73, 95% CI = 5.72 to 54.98, p < 0.001) than patients who did not receive physical treatment (group a). The mean speed of recovery in group b was the half of that recorded for group a (non-Kabat subjects). No difference was observed in the incidence of synkineses between the two groups. Steroid treatment appears to provide better and faster recovery in severe cases (HB IV and V) of BP when complemented with Kabat physical rehabilitation.

  18. Role of electron blocking layer in III-nitride laser diodes and light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Kuo, Yen-Kuang; Chang, Jih-Yuan; Chen, Mei-Ling

    2010-02-01

    A high energy bandgap electron blocking layer (EBL) just behind the active region is conventionally used in the nitride-based laser diodes (LDs) and light-emitting diodes (LEDs) to improve the confinement capability of electrons within the quantum wells. Nevertheless, the EBL may also act as a potential barrier for the holes and cause non-uniform distribution of holes among quantum wells. A most recent study by Han et al. (Appl. Phys. Lett. 94, 231123, 2009) reported that, because of the blocking effect for holes, the InGaN LED device without an EBL has slighter efficiency droop and higher light output at high level of current injection when compared with the LED device with an EBL. This result seems to contradict with the original intention of using the EBL. Furthermore, findings from our previous studies (IEEE J. Lightwave Technol. 26, 329, 2008; J. Appl. Phys. 103, 103115, 2008; Appl. Phys. Lett. 91, 201118, 2007) indicated that the utilization of EBL is essential for the InGaN laser diodes. Thus, in this work, the optical properties of the InGaN LDs and LEDs are explored numerically with the LASTIP simulation program and APSYS simulation program, respectively. The analyses focus particularly on the light output power, energy band diagrams, recombination rates, distribution of electrons and holes in the active region, and electron overflow. This study will then conclude with a discussion of the effect of EBL on the optical properties of the InGaN LDs and LEDs.

  19. Pelvic nerve input mediates descending modulation of homovisceral processing in the thoracolumbar spinal cord of the rat

    PubMed Central

    Wang, Gexin; Tang, Bin; Traub, Richard J.

    2007-01-01

    Background and aims Colonic afferents project to the lumbosacral and thoracolumbar spinal cord via the pelvic and hypogastric/lumbar colonic nerves, respectively. Both spinal regions process inflammatory colonic stimuli. The role of thoracolumbar segments in processing acute colorectal pain is questionable, however, since the lumbosacral spinal cord appears sufficient to process reflex responses to acute pain. Here we demonstrate that activity in pelvic nerve colonic afferents actively modulates thoracolumbar dorsal horn neuron processing of the same colonic stimulus via a supraspinal loop: homovisceral descending modulation. Methods Dorsal horn neurons were recorded in the rat thoracolumbar spinal cord following acute or chronic pelvic neurectomy and cervical cold block. Results Acute pelvic neurectomy or lidocaine inhibition of lumbosacral dorsal roots facilitated the excitatory response of thoracolumbar dorsal horn neurons to colorectal distention (CRD) and decreased the percentage of neurons inhibited by CRD, suggesting colonic input over the pelvic nerve inhibits thoracolumbar processing of the same stimulus. Ectopic activity developed in the proximal pelvic nerve following chronic neurectomy reactivating the inhibitory circuit, inhibiting thoracolumbar neurons. Cervical cold block alleviated the inhibition in intact or chronic neurectomized rats. However, the facilitated response following acute pelvic neurectomy was inhibited by cervical cold block exposing an underlying descending facilitation. Inhibiting pelvic nerve input following cervical cold block had minimal effect. Conclusion These data demonstrate that input over the pelvic nerve modulates the response of thoracolumbar spinal neurons to CRD via a supraspinal loop, and that increasing thoracolumbar processing increases visceral hyperalgesia. PMID:17916357

  20. A Prospective, Randomized, Double-Blind Study of the Anesthetic Efficacy of Sodium Bicarbonate Buffered 2% Lidocaine With 1 : 100,000 Epinephrine in Inferior Alveolar Nerve Blocks

    PubMed Central

    Whitcomb, Michael; Drum, Melissa; Reader, Al; Nusstein, John; Beck, Mike

    2010-01-01

    Abstract The authors, using a crossover design, randomly administered, in a double-blind manner, inferior alveolar nerve (IAN) blocks using a buffered 2% lidocaine with 1 : 100,000 epinephrine/sodium bicarbonate formulation and an unbuffered 2% lidocaine with 1 : 100,000 epinephrine formulation at 2 separate appointments spaced at least 1 week apart. An electric pulp tester was used in 4-minute cycles for 60 minutes to test for anesthesia of the first and second molars, premolars, and lateral and central incisors. Anesthesia was considered successful when 2 consecutive 80 readings were obtained within 15 minutes, and the 80 reading was continuously sustained for 60 minutes. For the buffered 2% lidocaine with 1 : 100,000 epinephrine/sodium bicarbonate formulation, successful pulpal anesthesia ranged from 10–71%. For the unbuffered 2% lidocaine with 1 : 100,000 epinephrine formulation, successful pulpal anesthesia ranged from 10–72%. No significant differences between the 2 anesthetic formulations were noted. The buffered lidocaine formulation did not statistically result in faster onset of pulpal anesthesia or less pain during injection than did the unbuffered lidocaine formulation. We concluded that buffering a 2% lidocaine with 1 : 100,000 epinephrine with sodium bicarbonate, as was formulated in the current study, did not statistically increase anesthetic success, provide faster onset, or result in less pain of injection when compared with unbuffered 2% lidocaine with 1 : 100,000 epinephrine for an IAN block. PMID:20553136

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

    PubMed

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

    2002-03-01

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

  2. Role of Mas receptor antagonist (A779) in renal hemodynamics in condition of blocked angiotensin II receptors in rats.

    PubMed

    Mansoori, A; Oryan, S; Nematbakhsh, M

    2016-03-01

    The vasodilatory effect of angiotensin 1-7 (Ang 1-7) is exerted in the vascular bed via Mas receptor (MasR) gender dependently. However, the crosstalk between MasR and angiotensin II (Ang II) types 1 and 2 receptors (AT1R and AT2R) may change some actions of Ang 1-7 in renal circulation. In this study by blocking AT1R and AT2R, the role of MasR in kidney hemodynamics was described. In anaesthetized male and female Wistar rats, the effects of saline as vehicle and MasR blockade (A779) were tested on mean arterial pressure (MAP), renal perfusion pressure (RPP), renal blood flow (RBF), and renal vascular resistance (RVR) when both AT1R and AT2R were blocked by losartan and PD123319, respectively. In male rats, when AT1R and AT2R were blocked, there was a tendency for the increase in RBF/wet kidney tissue weight (RBF/KW) to be elevated by A779 as compared with the vehicle (P=0.08), and this was not the case in female rats. The impact of MasR on renal hemodynamics appears not to be sexual dimorphism either when Ang II receptors were blocked. It seems that co-blockade of all AT1R, AT2R, and MasR may alter RBF/ KW in male more than in female rats. These findings support a crosstalk between MasR and Ang II receptors in renal circulation.

  3. 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

    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.

  4. 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

  5. The role of hypothalamic mTORC1 signaling in insulin regulation of food intake, body weight, and sympathetic nerve activity in male mice.

    PubMed

    Muta, Kenjiro; Morgan, Donald A; Rahmouni, Kamal

    2015-04-01

    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.

  6. Role of spinal 5-HT5A, and 5-HT1A/1B/1D, receptors in neuropathic pain induced by spinal nerve ligation in rats.

    PubMed

    Avila-Rojas, Sabino Hazael; Velázquez-Lagunas, Isabel; Salinas-Abarca, Ana Belen; Barragán-Iglesias, Paulino; Pineda-Farias, Jorge Baruch; Granados-Soto, Vinicio

    2015-10-05

    Serotonin (5-HT) participates in pain modulation by interacting with different 5-HT receptors. The role of 5-HT5A receptor in neuropathic pain has not previously studied. The purpose of this study was to investigate: A) the role of 5-HT5A receptors in rats subjected to spinal nerve injury; B) the expression of 5-HT5A receptors in dorsal spinal cord and dorsal root ganglia (DRG). Neuropathic pain was induced by L5/L6 spinal nerve ligation. Tactile allodynia in neuropathic rats was assessed with von Frey filaments. Western blot methodology was used to determine 5-HT5A receptor protein expression. Intrathecal administration (on day 14th) of 5-HT (10-100 nmol) or 5-carboxamidotryptamine (5-CT, 0.03-0.3 nmol) reversed nerve injury-induced tactile allodynia. Intrathecal non-selective (methiothepin, 0.1-0.8 nmol) and selective (SB-699551, 1-10 nmol) 5-HT5A receptor antagonists reduced, by ~60% and ~25%, respectively, the antiallodynic effect of 5-HT (100 nmol) or 5-CT (0.3 nmol). Moreover, both selective 5-HT1A and 5-HT1B/1D receptor antagonists, WAY-100635 (0.3-1 nmol) and GR-127935 (0.3-1 nmol), respectively, partially diminished the antiallodynic effect of 5-HT or 5-CT by about 30%. Injection of antagonists, by themselves, did not affect allodynia. 5-HT5A receptors were expressed in the ipsilateral dorsal lumbar spinal cord and DRG and L5/L6 spinal nerve ligation did not modify 5-HT5A receptor protein expression in those sites. Results suggest that 5-HT5A receptors reduce pain processing in the spinal cord and that 5-HT and 5-CT reduce neuropathic pain through activation of 5-HT5A and 5-HT1A/1B/1D receptors. These receptors could be an important part of the descending pain inhibitory system.

  7. Block of sodium channels by divalent mercury: role of specific cysteinyl residues in the P-loop region.

    PubMed

    Hisatome, I; Kurata, Y; Sasaki, N; Morisaki, T; Morisaki, H; Tanaka, Y; Urashima, T; Yatsuhashi, T; Tsuboi, M; Kitamura, F; Miake, J; Takeda, S i; Taniguchi, S i; Ogino, K; Igawa, O; Yoshida, A; Sato, R; Makita, N; Shigemasa, C

    2000-09-01

    Divalent mercury (Hg(2+)) blocked human skeletal Na(+) channels (hSkM1) in a stable dose-dependent manner (K(d) = 0.96 microM) in the absence of reducing agent. Dithiothreitol (DTT) significantly prevented Hg(2+) block of hSkM1, and Hg(2+) block was also readily reversed by DTT. Both thimerosal and 2,2'-dithiodipyridine had little effect on hSkM1; however, pretreatment with thimerosal attenuated Hg(2+) block of hSkM1. Y401C+E758C rat skeletal muscle Na(+) channels (mu1) that form a disulfide bond spontaneously between two cysteines at the 401 and 758 positions showed a significantly lower sensitivity to Hg(2+) (K(d) = 18 microM). However, Y401C+E758C mu1 after reduction with DTT had a significantly higher sensitivity to Hg(2+) (K(d) = 0.36 microM) than wild-type hSkM1. Mutants C753Amu1 (K(d) = 8.47 microM) or C1521A mu1 (K(d) = 8.63 microM) exhibited significantly lower sensitivity to Hg(2+) than did wild-type hSkM1, suggesting that these two conserved cysteinyl residues of the P-loop region may play an important role in the Hg(2+) block of the hSkM1 isoform. The heart Na(+) channel (hH1) was significantly more sensitive to low-dose Hg(2+) (K(d) = 0.43 microM) than was hSkM1. The C373Y hH1 mutant exhibited higher resistance (K(d) = 1.12 microM) to Hg(2+) than did wild-type hH1. In summary, Hg(2+) probably inhibits the muscle Na(+) channels at more than one cysteinyl residue in the Na(+) channel P-loop region. Hg(2+) exhibits a lower K(d) value (<1. 23 microM) for inhibition by forming a sulfur-Hg-sulfur bridge, as compared to reaction at a single cysteinyl residue with a higher K(d) value (>8.47 microM) by forming sulfur-Hg(+) covalently. The heart Na(+) channel isoform with more than two cysteinyl residues in the P-loop region exhibits an extremely high sensitivity (K(d) < 0. 43 microM) to Hg(+), accounting for heart-specific high sensitivity to the divalent mercury.

  8. Differential role of afferent and efferent renal nerves in the maintenance of early- and late-phase Dahl S hypertension

    PubMed Central

    Foss, Jason D.; Fink, Gregory D.

    2015-01-01

    Clinical data suggest that renal denervation (RDNX) may be an effective treatment for human hypertension; however, it is unclear whether this therapeutic effect is due to ablation of afferent or efferent renal nerves. We have previously shown that RDNX lowers arterial pressure in hypertensive Dahl salt-sensitive (S) rats to a similar degree observed in clinical trials. In addition, we have recently developed a method for selective ablation of afferent renal nerves (renal-CAP). In the present study, we tested the hypothesis that the antihypertensive effect of RDNX in the Dahl S rat is due to ablation of afferent renal nerves by comparing the effect of complete RDNX to renal-CAP during two phases of hypertension in the Dahl S rat. In the early phase, rats underwent treatment after 3 wk of high-NaCl feeding when mean arterial pressure (MAP) was ∼140 mmHg. In the late phase, rats underwent treatment after 9 wk of high NaCl feeding, when MAP was ∼170 mmHg. RDNX reduced MAP ∼10 mmHg compared with sham surgery in both the early and late phase, whereas renal-CAP had no antihypertensive effect. These results suggest that, in the Dahl S rat, the antihypertensive effect of RDNX is not dependent on pretreatment arterial pressure, nor is it due to ablation of afferent renal nerves. PMID:26661098

  9. THE OLFACTORY NERVE HAS A ROLE IN THE BODY TEMPERATURE AND BRAIN CYTOKINE RESPONSES TO INFLUENZA VIRUS

    PubMed Central

    Leyva-Grado, Victor H.; Churchill, Lynn; Harding, Joseph; Krueger, James M.

    2009-01-01

    Mouse-adapted human influenza virus is detectable in the olfactory bulbs of mice within hours after intranasal challenge and is associated with enhanced local cytokine mRNA and protein levels. To determine whether signals from the olfactory nerve influence the unfolding of the acute phase response (APR), we surgically transected the olfactory nerve in mice prior to influenza infection. We then compared the responses of olfactory nerve-transected (ONT) mice to those recorded in sham-operated control mice using measurements of body temperature, food intake, body weight, locomotor activity and immunohistochemistry for cytokines and the viral antigen, H1N1. ONT did not change baseline body temperature (Tb); however, the onset of virus-induced hypothermia was delayed for about 13 h in the ONT mice. Locomotor activity, food intake and body weights of the two groups were similar. At 15 h post-challenge fewer viral antigen-immunoreactive (IR) cells were observed in the olfactory bulb (OB) of ONT mice compared to sham controls. The number of tumor necrosis factor alpha (TNFα)- and interleukin 1 beta (IL1β)-IR cells in ONT mice was also reduced in the OB and other interconnected regions in the brain compared to sham controls. These results suggest that the olfactory nerve pathway is important for the initial pathogenesis of the influenza-induced APR. PMID:19836444

  10. 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

  11. Neuromuscular block.

    PubMed

    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 specially useful in kidney or liver failure, and the vecuronium group, which are specially free from unwanted side effects. Of this latter group, the compound rocuronium is of special 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.

  12. Nuclear factor-kappaB activation in axons and Schwann cells in experimental sciatic nerve injury and its role in modulating axon regeneration: studies with etanercept.

    PubMed

    Smith, Darrell; Tweed, Christopher; Fernyhough, Paul; Glazner, Gordon W

    2009-06-01

    Early inflammatory events may inhibit functional recovery after injury in both the peripheral and central nervous systems. We investigated the role of the inflammatory tumor necrosis factor/nuclear factor-kappaB (NF-kappaB) axis on events subsequent to sciatic nerve crush injury in adult rats. Electrophoretic mobility shift assays revealed that within 6 hours after crush, NF-kappaB DNA-binding activity increased significantly in a 1-cm section around the crush site. By immunofluorescence staining, there was increased nuclear localization of the NF-kappaB subunits p50 but not p65 or c-Rel in Schwann cells but no obvious inflammatory cell infiltration. In rats injected subcutaneously with etanercept, a tumor necrosis factor receptor chimera that binds free cytokine, the injury-induced rise in NF-kappaB DNA-binding activity was inhibited, and nuclear localization of p50 in Schwann cells was lowered after the injury. Axonal growth 3 days after nerve crush assessed with immunofluorescence for GAP43 demonstrated that the regeneration distance of leading axons from the site of nerve crush was greater in etanercept-treated animals than in saline-treated controls. These data indicate that tumor necrosis factor mediates rapid activation of injury-induced NF-kappaB DNA binding in Schwann cells and that these events are associated with inhibition of postinjury axonal sprouting.

  13. 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.

  14. Contrasting effects of verapamil and procainamide on rate-dependent bundle branch block: pharmacologic evidence for the role of depressed sodium channel responses.

    PubMed

    Chiale, P A; Pastori, J D; Sánchez, R A; Elizari, M V; Rosenbaum, M B

    1990-03-01

    The mechanisms responsible for intermittent bundle branch block are still under debate. The role of the time-dependent behavior of the slow calcium channel has recently been emphasized. To test this hypothesis and ascertain the possible involvement of the fast sodium channel, the effects of the slow calcium channel blocker verapamil and the fast sodium channel blocker procainamide were compared in 10 patients with intermittent bundle branch block. All 10 patients showed bundle branch block during spontaneous sinus rhythm. Maneuvers to slow cardiac rate (that is, carotid sinus massage, Valsalva maneuver) were performed to identify normal conduction as well as phase 4 bundle branch block. Thus, the ranges of diastolic intervals (RR) resulting in phase 3 (tachycardia-dependent) bundle branch block, phase 4 (bradycardia-dependent) bundle branch block and normal conduction were measured in two control studies performed before intravenous administration of verapamil (control 1) and procainamide (control 2) and at the peak effect of both drugs. In the control studies, all 10 patients showed phase 3 bundle branch block, whereas phase 4 bundle branch block occurred in only 4 patients. The ranges of phase 3 bundle branch block, phase 4 bundle branch block and normal conduction were very similar in control studies 1 and 2. The phase 3 bundle branch block range was slightly shortened by verapamil (983 +/- 83.5 ms in control 1; 930 +/- 69.4 ms at the peak effect of verapamil), whereas phase 4 bundle branch block remained unchanged. In contrast, conduction was systematically worsened by procainamide.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Block and boost DNA transfer: opposite roles of OmpA in natural and artificial transformation of Escherichia coli.

    PubMed

    Sun, Dongchang; Wang, Bing; Zhu, Lihong; Chen, Mengyao; Zhan, Linlin

    2013-01-01

    Our previous work established that DNA is naturally transferable on agar plates through a new transformation system which is regulated by the stationary phase master regulator RpoS in Escherichia coli. In this transformation system, neither additional Ca(2+) nor heat shock is required. Instead, transformation is stimulated by agar. The membrane protein OmpA, a gated pore permeable to ions and larger solutes, serves as a receptor for DNA transfer during bacteriophage infection and conjugation. However, it remains unknown how DNA transfers across membranes and whether OmpA is involved in transformation of E. coli. Here, we explored potential roles of OmpA in natural and chemical transformation of E. coli. We observed that ompA inactivation significantly improved natural transformation on agar plates, indicating that OmpA blocks DNA transfer. Transformation promotion by ompA inactivation also occurred on soft plates, indicating that OmpA blocks DNA transfer independent of agar. By contrast, compared with the wild-type strain, chemical transformation of the ompA mutant was lower, indicating that OmpA has a role in DNA transfer. Inactivation of ompA also reduced chemical transformation in solution containing less Ca(2+) or with a shortened time for heat shock, suggesting that the promotion effect of OmpA on DNA transfer does not solely rely on Ca(2+) or heat shock. We conclude that OmpA plays opposite roles in natural and chemical transformation: it blocks DNA uptake on agar plates but promotes DNA transfer in the liquid Ca(2+) solution. Considering that no single factor was identified to reverse the function of OmpA, we propose that multiple factors may cooperate in the functional reversal of OmpA during natural and artificial transformation of E. coli. Finally, we observed that ompA transcription was not affected by the expression of RpoS, excluding the possibility that RpoS regulates DNA transfer by suppressing ompA transcription.

  16. A role for Chk1 in blocking transcriptional elongation of p21 RNA during the S-phase checkpoint

    PubMed Central

    Beckerman, Rachel; Donner, Aaron J.; Mattia, Melissa; Peart, Melissa J.; Manley, James L.; Espinosa, Joaquin M.; Prives, Carol

    2009-01-01

    We reported previously that when cells are arrested in S phase, a subset of p53 target genes fails to be strongly induced despite the presence of high levels of p53. When DNA replication is inhibited, reduced p21 mRNA accumulation is correlated with a marked reduction in transcription elongation. Here we show that ablation of the protein kinase Chk1 rescues the p21 transcription elongation defect when cells are blocked in S phase, as measured by increases in both p21 mRNA levels and the presence of the elongating form of RNA polymerase II (RNAPII) toward the 3′ end of the p21 gene. Recruitment of specific elongation and 3′ processing factors (DSIF, CstF-64, and CPSF-100) is also restored. While additional components of the RNAPII transcriptional machinery, such as TFIIB and CDK7, are recruited more extensively to the p21 locus after DNA damage than after replication stress, their recruitment is not enhanced by ablation of Chk1. Significantly, ablating Chk2, a kinase closely related in substrate specificity to Chk1, does not rescue p21 mRNA levels during S-phase arrest. Thus, Chk1 has a direct and selective role in the elongation block to p21 observed during S-phase arrest. These findings demonstrate for the first time a link between the replication checkpoint mediated by ATR/Chk1 and the transcription elongation/3′ processing machinery. PMID:19487575

  17. 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

  18. [Role of cytokines and their blocking in immune-mediated inflammatory diseases].

    PubMed

    Matikainen, Sampsa; Jokiranta, Sakari; Eklund, Kari K

    2016-01-01

    Rheumatoid arthritis, inflammatory bowel diseases and psoriasis are examples of immune-mediated inflammatory diseases. They involve activation of a partly similar cytokine network that has an essential role in the disease pathogenesis. Biological drugs have been developed for the inhibition of single cytokines, and good therapeutic responses have been achieved by using them. For instance, TNF blockers are used in the treatment of several inflammatory diseases. The use of the blockers of certain other cytokines is more limited. Other important target molecules include certain interleukins. New bispecific antibodies enabling inhibition of the action of two distinct cytokines are currently undergoing clinical studies.

  19. Sympathetic nerve stimulation induces local endothelial Ca2+ signals to oppose vasoconstriction of mouse mesenteric arteries.

    PubMed

    Nausch, Lydia W M; Bonev, Adrian D; Heppner, Thomas J; Tallini, Yvonne; Kotlikoff, Michael I; Nelson, Mark T

    2012-02-01

    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 (IP(3))-mediated Ca(2+) 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) Ca(2+) pulsars, recruiting new pulsar sites without affecting activity at existing sites. This increase in Ca(2+) 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 Ca(2+) signaling was not blocked by inhibitors of purinergic receptors, ryanodine receptors, or voltage-dependent Ca(2+) channels, suggesting a role for IP(3), rather than Ca(2+), in VSM-to-endothelium communication. Block of intermediate-conductance Ca(2+)-sensitive K(+) channels, which have been shown to colocalize with IP(3) 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 Ca(2+) signals to oppose vasoconstriction.

  20. 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

  1. Blocking c-Fos Expression Reveals the Role of Auditory Cortex Plasticity in Sound Frequency Discrimination Learning.

    PubMed

    de Hoz, Livia; Gierej, Dorota; Lioudyno, Victoria; Jaworski, Jacek; Blazejczyk, Magda; Cruces-Solís, Hugo; Beroun, Anna; Lebitko, Tomasz; Nikolaev, Tomasz; Knapska, Ewelina; Nelken, Israel; Kaczmarek, Leszek

    2017-03-17

    The behavioral changes that comprise operant learning are associated with plasticity in early sensory cortices as well as with modulation of gene expression, but the connection between the behavioral, electrophysiological, and molecular changes is only partially understood. We specifically manipulated c-Fos expression, a hallmark of learning-induced synaptic plasticity, in auditory cortex of adult mice using a novel approach based on RNA interference. Locally blocking c-Fos expression caused a specific behavioral deficit in a sound discrimination task, in parallel with decreased cortical experience-dependent plasticity, without affecting baseline excitability or basic auditory processing. Thus, c-Fos-dependent experience-dependent cortical plasticity is necessary for frequency discrimination in an operant behavioral task. Our results connect behavioral, molecular and physiological changes and demonstrate a role of c-Fos in experience-dependent plasticity and learning.

  2. Neurosurgical procedures, spinal nerve roots - one stage removal of thoracic dumb-bell tumor: role of spinal evoked potential.

    PubMed

    Srivastava, Dharmendra Kumar; Singh, Deepak; Tiwari, Bhuwan Chandra; Awasthi, Namarata; Hussain, Nuzhat

    2014-02-01

    We report a rare case of benign thoracic dumb-bell tumor in the upper posterior mediastinum, which was successfully removed by posterolateral thoracotomy and foraminotomy, using intraoperative monitoring of spinal motor-evoked potentials. This technique has many advantages including minimal morbidity and mortality, a single incision, one-step complete resection with adequate exposure, spinal stabilization, avoidance of laminectomy, nerve root identification, and good predicted postoperative function.

  3. The role of NGF in pregnancy-induced degeneration and regeneration of sympathetic nerves in the guinea pig uterus.

    PubMed

    Brauer, M M; Shockley, K P; Chávez, R; Richeri, A; Cowen, T; Crutcher, K A

    2000-02-14

    In the guinea pig, pregnancy is associated with a generalised depletion of noradrenaline in uterine sympathetic nerves and, in the areas of the uterus surrounding the foetus, by a complete degeneration of sympathetic nerve fibres. These pregnancy-induced changes have been interpreted as a selective effect of placental hormones on the system of short sympathetic fibres arising from the paracervical ganglia. An alternative explanation is that pregnancy affects the neurotrophic capacity of the uterus. We measured NGF-protein levels in the guinea pig uterine horn, tubal end and cervix at early pregnancy, late pregnancy and early postpartum, using a two-site enzyme-linked immunosorbent assay. For comparative purposes the distribution and relative density of noradrenaline-containing sympathetic nerve fibres were assessed histochemically, and tissue levels of noradrenaline were measured biochemically, using high-performance liquid chromatography with electrochemical detection. In all the uterine regions analysed, NGF-protein levels showed a decline at term pregnancy, but in no case was this change statistically significant. After delivery, NGF-protein levels showed a marked increase in the cervix as well as in both the fertile and empty horns. These results suggest that alterations in NGF-protein do not account for the impairment of uterine sympathetic innervation during pregnancy, but may contribute to their recovery after delivery.

  4. Peripheral Nerve Injury: Stem Cell Therapy and Peripheral Nerve Transfer

    PubMed Central

    Sullivan, Robert; Dailey, Travis; Duncan, Kelsey; Abel, Naomi; Borlongan, Cesario V.

    2016-01-01

    Peripheral nerve injury can lead to great morbidity in those afflicted, ranging from sensory loss, motor loss, chronic pain, or a combination of deficits. Over time, research has investigated neuronal molecular mechanisms implicated in nerve damage, classified nerve injury, and developed surgical techniques for treatment. Despite these advancements, full functional recovery remains less than ideal. In this review, we discuss historical aspects of peripheral nerve injury and introduce nerve transfer as a therapeutic option, as well as an adjunct therapy to transplantation of Schwann cells and their stem cell derivatives for repair of the damaged nerve. This review furthermore, will provide an elaborated discussion on the sources of Schwann cells, including sites to harvest their progenitor and stem cell lines. This reflects the accessibility to an additional, concurrent treatment approach with nerve transfers that, predicated on related research, may increase the efficacy of the current approach. We then discuss the experimental and clinical investigations of both Schwann cells and nerve transfer that are underway. Lastly, we provide the necessary consideration that these two lines of therapeutic approaches should not be exclusive, but conversely, should be pursued as a combined modality given their mutual role in peripheral nerve regeneration. PMID:27983642

  5. Bone morphogenetic protein 4 inhibits TGF-beta2 stimulation of extracellular matrix proteins in optic nerve head cells: role of gremlin in ECM modulation.

    PubMed

    Zode, Gulab S; Clark, Abbot F; Wordinger, Robert J

    2009-05-01

    The characteristic cupping of the optic nerve head (ONH) in glaucoma is associated with elevated TGF-beta2 and increased synthesis and deposition of extracellular matrix (ECM) proteins. In addition to TGF-beta2, the human ONH also expresses bone morphogenetic proteins (BMPs) and BMP receptors, which are members of the TGF-beta superfamily. We examined the potential effects of BMP4 and the BMP antagonist gremlin on TGF-beta2 induction of ECM proteins in ONH cells. BMP-4 dose dependently inhibited TGF-beta2-induced fibronectin (FN) and PAI-1 expression in ONH astrocytes and lamina cribrosa (LC) cells and also reduced TGF-beta2 stimulation of collagen I, collagen VI, and elastin. Addition of gremlin blocked this BMP-4 response, increasing cellular and secreted FN as well as PAI-1 levels in both cell types. Gremlin was expressed in ONH tissues and ONH cells, and gremlin protein levels were significantly increased in the LC region of human glaucomatous ONH tissues. Interestingly, recombinant gremlin dose dependently increased ECM protein expression in cultured ONH astrocytes and LC cells. Gremlin stimulation of ECM required activation of TGF-beta receptor and R-Smad3. TGF-beta2 increased gremlin mRNA expression and protein levels in ONH cells. Inhibition of either the type I TGF-beta receptor or Smad3 phosphorylation blocked TGF-beta2-induced gremlin expression. In conclusion, BMP4 blocked the TGF-beta2 induction of ECM proteins in ONH cells. The BMP antagonist gremlin reversed this inhibition, allowing TGF-beta2 stimulation of ECM synthesis. Increased expression of gremlin in the glaucomatous ONH may further exacerbate TGF-beta2 effects on ONH ECM metabolism by inhibiting BMP-4 antagonism of TGF-beta2 signaling. Modulation of the ECM via gremlin provides a novel therapeutic target for glaucoma.

  6. Optic Nerve Decompression

    MedlinePlus

    ... Nerve Decompression Dacryocystorhinostomy (DCR) Disclosure Statement Printer Friendly Optic Nerve Decompression John Lee, MD Introduction Optic nerve decompression is a surgical procedure aimed at ...

  7. Ulnar nerve dysfunction

    MedlinePlus

    Neuropathy - ulnar nerve; Ulnar nerve palsy; Mononeuropathy; Cubital tunnel syndrome ... compressed in the elbow, a problem called cubital tunnel syndrome may result. When damage destroys the nerve ...

  8. Biological roles of anti-GM1 antibodies in patients with Guillain-Barré syndrome for nerve growth factor signaling.

    PubMed

    Tanaka, Toshifumi; Furutama, Daisuke; Sakai, Reiko; Fujita, Atsushi; Kimura, Fumiharu; Tagami, Muneyoshi; Ohsawa, Nakaaki; Hanafusa, Toshiaki

    2007-05-01

    To reveal the biological and pathological roles of anti-GM1 antibody in Guillain-Barré syndrome (GBS), we examined its effects on nerve growth factor (NGF) induced TrkA autophosphorylation (NGF-TrkA signaling) in PC12 cells, a sympathetic nerve cell line. The NGF-TrkA signaling is enhanced by exogenous GM1 ganglioside and this phenomenon is regarded as one of the functional aspects of GM1. The IgGs purified from patients' sera inhibited the NGF-TrkA signaling in GM1 pre-incubated PC12 cells. The degrees of inhibition by IgGs from patients paralleled their immunological reactivity to GM1. In addition, the IgGs also inhibited the neurite outgrowth of NGF-treated PC12 cells. Immunoglobulins in the rabbit sera, which were immunized by GM1, also caused a similar suppressive phenomenon. These results suggested that the anti-GM1 antibody could play roles in pathophysiology in anti-GM1 antibody positive GBS through interfering with the neurotrophic action of NGF and GM1 mediated signal modulation including NGF-TrkA signaling. It is suggested that the modulation of GM1 function is one important action of antibodies and could be one of the important mechanisms in GBS.

  9. Is the vagus nerve stimulation a way to decrease body weight in humans?

    PubMed

    Bugajski, Andrzej; Gil, Krzysztof

    2012-01-01

    Obesity and its complications constitute an important health problem in growing number of people. Behavioral and pharmacological treatment is not much effective and surgical treatment carries too many threats. Promising method to be used is pharmacological or electric manipulation of vagus nerves. Regulation of food intake and energy utilization is a complex process regulated by centers in hypothalamus and brainstem which are receiving information from the peripheral via afferent neural pathways and sending peripherally adequate instructions by efferent neural pathways. In these signals conduction an important role plays vagus nerve. Additionally central nervous system stays under influence of endocrine, paracrine and neuroendocrine signals taking part in these regulations, functioning directly onto the centre or on the afferent neural endings. 80-90% fibers of vagus nerve are afferent fibers, so their action is mainly afferent, but possible contribution of the efferent fibers cannot be excluded. Efferent stimulation induces motility and secretion in the intestinal tract. Afferent unmyelinated C-type fibres of the vagus nerve are more sensitive and easily electrically stimulated. Information from vagus nerve is transmitted to nucleus tractus solitarius, which has projections to nucleus arcuate of the medio-basal hypothalamus, involved in the control of feeding behavior. It is suggested, that interaction onto the vagus nerve (stimulation or blocking) can be an alternative for other ways of obesity treatment. Through the manipulation of the vagus nerve activity the goal is achieved by influence on central nervous system regulating the energy homeostasis.

  10. The Potential Role of Endometrial Nerve Fibers in the Pathogenesis of Pain During Endometrial Biopsy at Office Hysteroscopy

    PubMed Central

    Di Spiezio Sardo, Attilio; Fernandez, Loredana Maria Sosa; Guerra, Germano; Spinelli, Marialuigia; Di Carlo, Costantino; Filippeschi, Marco; Nappi, Carmine

    2015-01-01

    We aimed to evaluate whether nerve fibers are present in the endometrial layer of patients submitted to office hysteroscopy and their potential contribution to the pathogenesis of pain during that procedure. Through a prospective case–control study performed in tertiary centers for women’s health, endometrium samples were collected during operative office hysteroscopy from 198 cycling women who previously underwent laparoscopy and/or magnetic resonance imaging investigation for infertility assessment. Samples were classified according to the degree of the pain patients experienced and scored from values ranging from 0 (absence of discomfort/pain) to 10 (intolerable pain) on a 10-cm visual analog scale (VAS). The presence of nerve fiber markers (S100, NSE, SP, VIP, NPY, NKA, NKB, NKR1, NKR2, and NKR3) in the endometrium was also evaluated by morphologic and immunohistochemical analyses. We found that S-100, NSE, NKR1, NK-A, NK-B, VIP, and NPY, were immunolocalized in samples of endometrium, in significantly (P < .01, for all) higher levels in samples collected from patients with VAS score > 5 (group A) than ≤ 5 (group B) and significantly (P < .0001 for all) positively correlated with VAS levels. A statistically significant (P = .018) higher prevalence of endometriosis and/or adenomyosis was depicted in patients of group A than group B. Data from the present study led us to conclude that nerve fibers are expressed at the level of the functional layer of the endometrium and may contribute to pain generation during office hysteroscopy, mainly in women affected by endometriosis and adenomyosis. PMID:24807378

  11. 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

  12. Cardiac autonomic nerve distribution and arrhythmia☆

    PubMed Central

    Liu, Quan; Chen, Dongmei; Wang, Yonggang; Zhao, Xin; Zheng, Yang

    2012-01-01

    OBJECTIVE: To analyze the distribution characteristics of cardiac autonomic nerves and to explore the correlation between cardiac autonomic nerve distribution and arrhythmia. DATA RETRIEVAL: A computer-based retrieval was performed for papers examining the distribution of cardiac autonomic nerves, using heart, autonomic nerve, sympathetic nerve, vagus nerve, nerve distribution, rhythm and atrial fibrillation as the key words. SELECTION CRITERIA: A total of 165 studies examining the distribution of cardiac autonomic nerve were screened, and 46 of them were eventually included. MAIN OUTCOME MEASURES: The distribution and characteristics of cardiac autonomic nerves were observed, and immunohistochemical staining was applied to determine the levels of tyrosine hydroxylase and acetylcholine transferase (main markers of cardiac autonomic nerve distribution). In addition, the correlation between cardiac autonomic nerve distribution and cardiac arrhythmia was investigated. RESULTS: Cardiac autonomic nerves were reported to exhibit a disordered distribution in different sites, mainly at the surface of the cardiac atrium and pulmonary vein, forming a ganglia plexus. The distribution of the pulmonary vein autonomic nerve was prominent at the proximal end rather than the distal end, at the upper left rather than the lower right, at the epicardial membrane rather than the endocardial membrane, at the left atrium rather than the right atrium, and at the posterior wall rather than the anterior wall. The main markers used for cardiac autonomic nerves were tyrosine hydroxylase and acetylcholine transferase. Protein gene product 9.5 was used to label the immunoreactive nerve distribution, and the distribution density of autonomic nerves was determined using a computer-aided morphometric analysis system. CONCLUSION: The uneven distribution of the cardiac autonomic nerves is the leading cause of the occurrence of arrhythmia, and the cardiac autonomic nerves play an important role in

  13. 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

  14. Role of splanchnic nerve on steroid-hormone-induced alteration of adrenomedullary catecholamines in untreated and reserpinized pigeon.

    PubMed

    Mahata, S K; Ghosh, A

    1991-01-01

    The aim of the present investigation was to ascertain (1) the effect of steroid hormones (corticosterone, dexamethasone, deoxycorticosterone, progesterone, testosterone and oestrogen) on the neural regulation of adrenomedullary catecholamine (CA) content, and (2) the neural modulation of the effect of glucocorticoid hormones (corticosterone and dexamethasone) on reserpine-induced resynthesis of CA. The experiment was conducted on unilaterally splanchnic-denervated pigeons. The findings revealed that 7 consecutive days of steroid treatments (2.5 mg.kg b.w.-1, i.m.) resulted in significant changes of CA content. Interestingly, the changes of epinephrine (E) content differed significantly between the innervated and denervated glands. This clearly indicates that the splanchnic nerve regulates steroid-induced alterations of E content in the pigeon. The results further revealed that the glucocorticoid hormones augmented reserpine-induced resynthesis of CA specifically in the innervated glands. This confirms that the splanchnic nerve is essential for the synergistic action of glucocorticoids and reserpine in accelerating resynthesis of CA.

  15. Vagus Nerve Stimulation

    MedlinePlus

    Vagus nerve stimulation Overview By Mayo Clinic Staff Vagus nerve stimulation is a procedure that involves implantation of a device that stimulates the vagus nerve with electrical impulses. There's one vagus nerve on ...

  16. 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 ...

  17. [Ultrasound for peripheral neural block].

    PubMed

    Kefalianakis, F

    2005-03-01

    Ultrasound is well established in medicine. Unfortunately, ultrasound is still rarely used in the area of anesthesia. The purpose of the article is to illustrate the possibilities and limitations of ultrasound in regional anesthesia. The basic principles of ultrasound are the piezoelectric effect and the behaviour of acoustic waveforms in human tissue. Ultrasound imaging in medicine uses high frequency pulses of sound waves (2.5-10 MHz). The following images are built up from the reflected sounds. The ultrasound devices used in regional anesthesia (commonly by 10 MHz) deliver a two-dimensional view. The main step for a successful regional anaesthesia is to identify the exact position of the nerve. In addition, specific surface landmarks and the use of peripheral nerve stimulator help to detect the correct position of the needle. Nerves are demonstrated as an composition of hyperechogenic (white) and hypoechogenic (black) areas. The surrounding hyperechogenic parts are epi- and perineurium, the dark hypoechogenic part is the neural tissue. The composition of peripheral nerves are always similar, but the quantities of each part, of surrounding perineurium and nerval structures, differ. Further the imaging of nerves is significantly influenced by the angle of beam to the nerve and the surrounding anatomic structures. Only experience and correct interpretation make the ultrasound a valid method in clinical practice. Correct interpretation has to be learned by standardized education. Three examples of peripheral nerve blocks are described. The detection of nerves and the visualization of the correct spread of local anesthetics to the nerves are the main principles of effective ultrasound-guided regional anesthesia, whereas closest proximity of the needle to the target nerve is not necessary. The described examples of ultrasound guidance for nerval block illustrates the specific procedures with reduced probability of nerval irritation, high success and low rate of

  18. Neuro-muscular junction block stimulator simulator.

    PubMed

    Sprick, Cyle

    2006-03-01

    Improved technology and higher fidelity are making medical simulations increasingly popular. A simulated peripheral nerve stimulator and thumb actuator has been developed for use with the SimMan Universal Patient Simulator. This device incorporates a handheld control box, a McKibben pneumatic muscle and articulated thumb, and a remote software interface for the simulation facilitator. The system simulates the action of a peripheral nerve stimulator on the ulnar nerve, and the effects of neuromuscular junction blocking agents on the thumb motion.

  19. Abnormal neutrophil chemotactic activity in children with congenital insensitivity to pain with anhidrosis (CIPA): the role of nerve growth factor.

    PubMed

    Beigelman, Avraham; Levy, Jacov; Hadad, Nurit; Pinsk, Vered; Haim, Alon; Fruchtman, Yariv; Levy, Rachel

    2009-03-01

    A 1926-ins-T mutation in the TrkA gene encoding the tyrosine kinase receptor for nerve growth factor (NGF) was previously documented in patients with congenital insensitivity to pain with anhidrosis (CIPA). These patients suffer from skin lacerations which often evolve into deep tissue infections. Abnormality in neutrophil functions may explain this high rate of severe infections. In this study we show that chemotaxis was significantly (P<0.001) suppressed in patients' neutrophils, compared to healthy controls. Although NGF alone did not exert a chemotactic effect, its presence enhanced both migration toward fMLP and phosphorylation of MAP kinases (ERK and JNK) in neutrophils from healthy controls, but not in neutrophils from CIPA patients. The significantly impaired chemotactic activity of neutrophils from a CIPA patient, which has been attributed to the molecular defect in the TrkA receptor, may contribute to the high rate of infection.

  20. The role of renal nerve ablation for the management of resistant hypertension and other disease conditions: benefits and concerns.

    PubMed

    Faselis, C; Doumas, M; Kokkinos, P; Tsioufis, C; Papademetriou, V

    2014-01-01

    The sympathetic nervous system is overactivated in resistant hypertension and several other disease conditions. A reciprocal association between the brain and the kidney has been described, in that sympathetic overactivity affects renal function while renal injury stimulates central sympathetic drive. Renal nerve ablation has been recently introduced as a potential alternative for the management of resistant hypertension, mainly due to current limitations in pharmacologic antihypertensive therapy. Data accumulated thus far point towards an efficacious and safe interventional method for the management of treatment resistance, with additional benefits on glucose metabolism and cardiac structure and function. Furthermore, beneficial effects have been observed in patients with chronic kidney disease, obstructive sleep apnea, polycystic ovary syndrome, and sympathetically driven tachyarrhythmias. However, as with every novel technique, several questions need to be answered and concerns need to be addressed before the wide application of this interventional approach.

  1. WWC Quick Review of the Report "The Role of Simplification and Information in College Decisions: Results from the H&R Block FAFSA Experiment" Revised

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2010

    2010-01-01

    This paper presents an updated WWC (What Works Clearinghouse) Quick Review of the report "The Role of Simplification and Information in College Decisions: Results from the H&R Block FAFSA Experiment". The study examined whether assistance in filling out the Free Application for Federal Student Aid (FAFSA) increases the likelihood of…

  2. WWC Quick Review of the Report "The Role of Simplification and Information in College Decisions: Results from the H&R Block FAFSA Experiment"

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2010

    2010-01-01

    This paper presents a WWC (What Works Clearinghouse) Quick Review of the report "The Role of Simplification and Information in College Decisions: Results from the H&R Block FAFSA Experiment". The study examined whether assistance in filling out the Free Application for Federal Student Aid (FAFSA) increases the likelihood of filing…

  3. The role of pre-existing tectonic structures and magma chamber shape on the geometry of resurgent blocks: Analogue models

    NASA Astrophysics Data System (ADS)

    Marotta, Enrica; de Vita, Sandro

    2014-02-01

    A set of analogue models has been carried out to understand the role of an asymmetric magma chamber on the resurgence-related deformation of a previously deformed crustal sector. The results are then compared with those of similar experiments, previously performed using a symmetric magma chamber. Two lines of experiments were performed to simulate resurgence in an area with a simple graben-like structure and resurgence in a caldera that collapsed within the previously generated graben-like structure. On the basis of commonly accepted scaling laws, we used dry-quartz sand to simulate the brittle behaviour of the crust and Newtonian silicone to simulate the ductile behaviour of the intruding magma. An asymmetric shape of the magma chamber was simulated by moulding the upper surface of the silicone. The resulting empty space was then filled with sand. The results of the asymmetric-resurgence experiments are similar to those obtained with symmetrically shaped silicone. In the sample with a simple graben-like structure, resurgence occurs through the formation of a discrete number of differentially displaced blocks. The most uplifted portion of the deformed depression floor is affected by newly formed, high-angle, inward-dipping reverse ring-faults. The least uplifted portion of the caldera is affected by normal faults with similar orientation, either newly formed or resulting from reactivation of the pre-existing graben faults. This asymmetric block resurgence is also observed in experiments performed with a previous caldera collapse. In this case, the caldera-collapse-related reverse ring-fault is completely erased along the shortened side, and enhances the effect of the extensional faults on the opposite side, so facilitating the intrusion of the silicone. The most uplifted sector, due to an asymmetrically shaped intrusion, is always in correspondence of the thickest overburden. These results suggest that the stress field induced by resurgence is likely dictated by

  4. 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

  5. [Monitoring of recurrent laryngeal nerve injury using an electromyographic endotracheal tube in thyroid and parathyroid surgery. Anesthetic aspects].

    PubMed

    Martín Jaramago, J; Tamarit Conejeros, M; Escudero Torrella, M; Solaz Roldán, C

    2013-12-01

    Recurrent laryngeal nerve injury remains one of the main complications in thyroid and parathyroid surgery. When this injury is bilateral, an acute upper airway obstruction may occur, leading to a potentially life-threatening situation for the patient. The visual identification of the nerve during surgery is the best way to preserve its integrity. However identification of the nerves by means of electromyographic stimuli through electrodes attached to endotracheal tubes could help in decreasing nerve injury. In these cases the experience and role of the anesthetist is essential to correctly place the electromyographic endotracheal tube and ensure that the electrodes are in touch with the vocal cords during the surgery. Moreover, the results of the electromyography can be affected by the neuromuscular blocking agents. Therefore, the choice and dose must be adapted, in order to ensure a suitable anesthetic depth, and adequate response.

  6. Optic Nerve.

    PubMed

    Gordon, Lynn K

    2016-10-28

    Optic nerve diseases arise from many different etiologies including inflammatory, neoplastic, genetic, infectious, ischemic, and idiopathic. Understanding some of the characteristics of the most common optic neuropathies along with therapeutic approaches to these diseases is helpful in designing recommendations for individual patients. Although many optic neuropathies have no specific treatment, some do, and it is those potentially treatable or preventable conditions which need to be recognized in order to help patients regain their sight or develop a better understanding of their own prognosis. In this chapter several diseases are discussed including idiopathic intracranial hypertension, optic neuritis, ischemic optic neuropathies, hereditary optic neuropathies, trauma, and primary tumors of the optic nerve. For each condition there is a presentation of the signs and symptoms of the disease, in some conditions the evaluation and diagnostic criteria are highlighted, and where possible, current therapy or past trials are discussed.

  7. 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.

  8. Expression changes of nerve cell adhesion molecules L1 and semaphorin 3A after peripheral nerve injury

    PubMed Central

    He, Qian-ru; Cong, Meng; Chen, Qing-zhong; Sheng, Ya-feng; Li, Jian; Zhang, Qi; Ding, Fei; Gong, Yan-pei

    2016-01-01

    The expression of nerve cell adhesion molecule L1 in the neuronal growth cone of the central nervous system is strongly associated with the direction of growth of the axon, but its role in the regeneration of the peripheral nerve is still unknown. This study explored the problem in a femoral nerve section model in rats. L1 and semaphorin 3A mRNA and protein expressions were measured over the 4-week recovery period. Quantitative polymerase chain reaction showed that nerve cell adhesion molecule L1 expression was higher in the sensory nerves than in motor nerves at 2 weeks after injury, but vice versa for the expression of semaphorin 3A. Western blot assay results demonstrated that nerve cell adhesion molecule L1 expression was higher in motor nerves than in the sensory nerves at the proximal end after injury, but its expression was greater in the sensory nerves at 2 weeks. Semaphorin 3A expression was higher in the motor nerves than in the sensory nerves at 3 days and 1 week after injury. Nerve cell adhesion molecule L1 and semaphorin 3A expressions at the distal end were higher in the motor nerves than in the sensory nerves at 3 days, 1 and 2 weeks. Immunohistochemical staining results showed that nerve cell adhesion molecule L1 expression at the proximal end was greater in the sensory nerves than in the motor nerves; semaphorin 3A expression was higher in the motor nerves than in the sensory nerves at 2 weeks after injury. Taken together, these results indicated that nerve cell adhesion molecules L1 and semaphorin 3A exhibited different expression patterns at the proximal and distal ends of sensory and motor nerves, and play a coordinating role in neural chemotaxis regeneration. PMID:28197202

  9. Role of the activation gate in determining the extracellular potassium dependency of block of HERG by trapped drugs.

    PubMed

    Pareja, Kristeen; Chu, Elaine; Dodyk, Katrina; Richter, Kristofer; Miller, Alan

    2013-01-01

    Drug induced long QT syndrome (diLQTS) results primarily from block of the cardiac potassium channel HERG (human-ether-a-go-go related gene). In some cases long QT syndrome can result in the lethal arrhythmia torsade de pointes, an arrhythmia characterized by a rapid heart rate and severely compromised cardiac output. Many patients requiring medication present with serum potassium abnormalities due to a variety of conditions including gastrointestinal dysfunction, renal and endocrine disorders, diuretic use, and aging. Extracellular potassium influences HERG channel inactivation and can alter block of HERG by some drugs. However, block of HERG by a number of drugs is not sensitive to extracellular potassium. In this study, we show that block of WT HERG by bepridil and terfenadine, two drugs previously shown to be trapped inside the HERG channel after the channel closes, is insensitive to extracellular potassium over the range of 0 mM to 20 mM. We also show that bepridil block of the HERG mutant D540K, a mutant channel that is unable to trap drugs, is dependent on extracellular potassium, correlates with the permeant ion, and is independent of HERG inactivation. These results suggest that the lack of extracellular potassium dependency of block of HERG by some drugs may in part be related to the ability of these drugs to be trapped inside the channel after the channel closes.

  10. 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

  11. 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.

  12. Sciatic nerve regeneration using a nerve growth factor-containing fibrin glue membrane.

    PubMed

    Ma, Shengzhong; Peng, Changliang; Wu, Shiqing; Wu, Dongjin; Gao, Chunzheng

    2013-12-25

    Our previous findings confirmed that the nerve growth factor-containing fibrin glue membrane provides a good microenvironment for peripheral nerve regeneration; however, the precise mechanism remains unclear. p75 neurotrophin receptor (p75(NTR)) plays an important role in the regulation of peripheral nerve regeneration. We hypothesized that a nerve growth factor-containing fibrin glue membrane can promote neural regeneration by up-regulating p75(NTR) expression. In this study, we used a silicon nerve conduit to bridge a 15 mm-long sciatic nerve defect and injected a mixture of nerve growth factor and fibrin glue at the anastomotic site of the nerve conduit and the sciatic nerve. Through RT-PCR and western blot analysis, nerve growth factor-containing fibrin glue membrane significantly increased p75(NTR) mRNA and protein expression in the Schwann cells at the anastomotic site, in particular at 8 weeks after injection of the nerve growth factor/fibrin glue mixture. These results indicate that nerve growth factor-containing fibrin glue membrane can promote peripheral nerve regeneration by up-regulating p75(NTR) expression in Schwann cells.

  13. Competency of Anopheles stephensi mysorensis strain for Plasmodium vivax and the role of inhibitory carbohydrates to block its sporogonic cycle

    PubMed Central

    Basseri, Hamid R; Doosti, Soghra; Akbarzadeh, Kamran; Nateghpour, Mehdi; Whitten, Miranda MA; Ladoni, Hossein

    2008-01-01

    Background Despite the abundance of studies conducted on the role of mosquitoes in malaria transmission, the biology and interaction of Plasmodium with its insect host still holds many mysteries. This paper provides the first study to follow the sporogonic cycle of Plasmodium vivax in a wild insecticide-resistant mysorensis strain of Anopheles stephensi, a major vector of vivax malaria in south-eastern Iran. The study subsequently demonstrates that host-parasite sugar binding interactions are critical to the development of this parasite in the salivary glands of its mosquito host. The identity of the receptors or sugars involved was revealed by a receptor "pre-saturation" strategy in which sugars fed to the mosquitoes inhibited normal host-parasite interactions. Methods Anopheles stephensi mysorensis mosquitoes were artificially infected with P. vivax by feeding on the blood of gametocytaemic volunteers reporting to local malaria clinics in the Sistan-Baluchistan province of south-eastern Iran. In order to determine the inhibitory effect of carbohydrates on sporogonic development, vector mosquitoes were allowed to ingest blood meals containing both gametocytes and added carbohydrates. The carbohydrates tested were GlcNAc, GalNAc, arabinose, fucose, mannose, lactose, glucose and galactose. Sporogonic development was assessed by survival of the parasite at both the oocyst and sporozoite stages. Results Oocyst development was observed among nearly 6% of the fed control mosquitoes but the overall number of mosquitoes exhibiting sporozoite invasion of the salivary glands was 47.5% lower than the number supporting oocysts in their midgut. Of the tested carbohydrates, only arabinose and fucose slightly perturbed the development of P. vivax oocysts at the basal side of the mosquito midgut, and the remaining sugars caused no reductions in oocyst development. Strikingly however, sporozoites were completely absent from the salivary glands of mosquitoes treated with mannose

  14. Nerve conduction velocity

    MedlinePlus

    ... polyneuropathy Tibial nerve dysfunction Ulnar nerve dysfunction Any peripheral neuropathy can cause abnormal results. Damage to the spinal ... Herniated disk Lambert-Eaton syndrome Mononeuropathy Multiple ... azotemia Primary amyloidosis Radial nerve dysfunction Sciatica ...

  15. Negativity of Fukui function of some isolated s and p block elements: The role of orbital relaxation effect

    NASA Astrophysics Data System (ADS)

    Bhattacharjee, Rituparna; Roy, Ram Kinkar

    2015-09-01

    In the present article, we emphasize the correlation between orbital relaxation effect and nature of atomic Fukui functions. While doing so, f- (rbar) and f+ (rbar) values are found to be positive and negative, respectively, for the chosen s block elements. Also, f- (rbar) and f+ (rbar) values for chosen p block atoms are negative. Nodal nature of the highest occupied and lowest unoccupied orbitals, electron-electron repulsion and effective nuclear charge become handy in explaining the observed trends. Out of track results obtained for the inert atoms are also explained.

  16. Heart Block

    MedlinePlus

    ... not used to treat first-degree heart block. All types of heart block may increase your risk for other arrhythmias, such as atrial fibrillation (A-tre-al fih-brih-LA-shun). Talk with your doctor ...

  17. An anatomical evaluation of the serratus anterior plane block.

    PubMed

    Mayes, J; Davison, E; Panahi, P; Patten, D; Eljelani, F; Womack, J; Varma, M

    2016-09-01

    The serratus anterior plane block has been described for analgesia of the hemithorax. This study was conducted to determine the spread of injectate and investigate the anatomical basis of the block. Ultrasound-guided serratus anterior plane block was performed on six soft-fix embalmed cadavers. All cadavers received bilateral injections, on one side performed with 20 ml latex and on the other with 20 ml methylene blue. Subsequent dissection explored the extent of spread and nerve involvement. Photographs were taken throughout dissection. The intercostal nerves were involved on three occasions with dye, but not with latex. The lateral cutaneous branches of the intercostal nerve contained dye and latex on all occasions. The serratus plane block appears to be mediated through blockade of the lateral cutaneous branches of the intercostal nerves. Anatomically, serratus plane block does not appear to be equivalent to paravertebral block for rib fracture analgesia.

  18. 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)

  19. 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…

  20. The role of inactivation in open-channel block of the sodium channel: studies with inactivation-deficient mutant channels.

    PubMed

    Grant, A O; John, J E; Nesterenko, V V; Starmer, C F; Moorman, J R

    1996-12-01

    Inactivation has been implicated as an important determinant of the block of Na+ channel by local anesthetic-class drugs. This proposition has been difficult to examine because agents used to modify inactivation change other channel properties and both inactivated and blocked channels do not conduct. We used site-directed mutagenesis of Phe1304 to glutamine in the linker between the third and fourth domains of the mu-1 Na+ channel to slow inactivation. Wild-type and mutant channels were expressed in frog oocytes. Macropatch and single-channel currents were recorded in cell-attached membrane patches. The F1304Q mutation increased mean open time (1.7 fold at -20 mV) and reduced the probability that the channel would fail to open. Closed times were best fit by a double-exponential function, suggesting that the inactivated state transitions were no longer absorbing. In wild-type channels, 100 microM disopyramide decreased mean open time from 1.64 +/- 0.08 to 0.34 +/- 0.04 msec. Total open time per trial was decreased 2-fold. There also was a marked increase in the fraction of null sweeps. In the inactivation-deficient mutant channel, mean and total open times were also reduced. These data indicate that even when inactivation is slowed by a localized specific mutation, open-channel block by disopyramide persists. Inactivation may not be a necessary requirement for open-channel block.

  1. Nerve transfers in brachial plexus birth palsies: indications, techniques, and outcomes.

    PubMed

    Kozin, Scott H

    2008-11-01

    The advent of nerve transfers has greatly increased surgical options for children who have brachial plexus birth palsies. Nerve transfers have considerable advantages, including easier surgical techniques, avoidance of neuroma resection, and direct motor and sensory reinnervation. Therefore, any functioning nerve fibers within the neuroma are preserved. Furthermore, a carefully selected donor nerve results in little or no clinical deficit. However, some disadvantages and unanswered questions remain. Because of a lack of head-to-head comparison between nerve transfers and nerve grafting, the window of opportunity for nerve grafting may be missed, which may degrade the ultimate outcome. Time will tell the ultimate role of nerve transfer or nerve grafting.

  2. 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

  3. Role of Mg(2+) block of the inward rectifier K(+) current in cardiac repolarization reserve: A quantitative simulation.

    PubMed

    Ishihara, Keiko; Sarai, Nobuaki; Asakura, Keiichi; Noma, Akinori; Matsuoka, Satoshi

    2009-07-01

    Different K(+) currents serve as "repolarization reserve" or a redundant repolarizing mechanism that protects against excessive prolongation of the cardiac action potential and therefore arrhythmia. Impairment of the inward rectifier K(+) current (I(K1)) has been implicated in the pathogenesis of cardiac arrhythmias. The characteristics of I(K1) reflect the kinetics of channel block by intracellular cations, primarily spermine (a polyamine) and Mg(2+), whose cellular levels may vary under various pathological conditions. However, the relevance of endogenous I(K1) blockers to the repolarization reserve is still not fully understood in detail. Here we used a mathematical model of a cardiac ventricular myocyte which quantitatively reproduces the dynamics of I(K1) block to examine the effects of the intracellular spermine and Mg(2+) concentrations, through modifying I(K1), on the action potential repolarization. Our simulation indicated that an I(K1) transient caused by relief of Mg(2+) block flows during early phase 3. Increases in the intracellular spermine/Mg(2+) concentration, or decreases in the intracellular Mg(2+) concentration, to levels outside their normal ranges prolonged action potential duration by decreasing the I(K1) transient. Moreover, reducing both the rapidly activating delayed rectifier current (I(Kr)) and the I(K1) transient caused a marked retardation of repolarization and early afterdepolarization because they overlap in the voltage range at which they flow. Our results indicate that the I(K1) transient caused by relief of Mg(2+) block is an important repolarizing current, especially when I(Kr) is reduced, and that abnormal intracellular free spermine/Mg(2+) concentrations may be a missing risk factor for malignant arrhythmias in I(Kr)-related acquired (drug-induced) and congenital long QT syndromes.

  4. The role of deformation and other quantities in an equation for enstrophy as applied to atmospheric blocking

    NASA Astrophysics Data System (ADS)

    Jensen, Andrew D.; Lupo, Anthony R.

    2014-06-01

    In this note, equations for enstrophy and enstrophy advection are derived in terms of well-known quantities, assuming horizontal frictionless flow on a beta-plane. Specifically, enstrophy can be written in terms of the geopotential (or pressure), relative vorticity, zonal wind, and resultant deformation. Enstrophy advection is shown to be related to the time evolution of deformation and ageostrophic relative vorticity. Based on previous research, these terms may contribute to instability associated with atmospheric blocking development and decay.

  5. 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

  6. 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

  7. Firing patterns and functional roles of different classes of spinal afferents in rectal nerves during colonic migrating motor complexes in mouse colon.

    PubMed

    Zagorodnyuk, Vladimir P; Kyloh, Melinda; Brookes, Simon J; Nicholas, Sarah J; Spencer, Nick J

    2012-08-01

    The functional role of the different classes of visceral afferents that innervate the large intestine is poorly understood. Recent evidence suggests that low-threshold, wide-dynamic-range rectal afferents play an important role in the detection and transmission of visceral pain induced by noxious colorectal distension in mice. However, it is not clear which classes of spinal afferents are activated during naturally occurring colonic motor patterns or during intense contractions of the gut smooth muscle. We developed an in vitro colorectum preparation to test how the major classes of rectal afferents are activated during spontaneous colonic migrating motor complex (CMMC) or pharmacologically induced contraction. During CMMCs, circular muscle contractions increased firing in low-threshold, wide-dynamic-range muscular afferents and muscular-mucosal afferents, which generated a mean firing rate of 1.53 ± 0.23 Hz (n = 8) under isotonic conditions and 2.52 ± 0.36 Hz (n = 17) under isometric conditions. These low-threshold rectal afferents were reliably activated by low levels of circumferential stretch induced by increases in length (1-2 mm) or load (1-3 g). In a small proportion of cases (5 of 34 units), some low-threshold muscular and muscular-mucosal afferents decreased their firing rate during the peak of the CMMC contractions. High-threshold afferents were never activated during spontaneous CMMC contractions or tonic contractions induced by bethanechol (100 μM). High-threshold rectal afferents were only activated by intense levels of circumferential stretch (10-20 g). These results show that, in the rectal nerves of mice, low-threshold, wide-dynamic-range muscular and muscular-mucosal afferents are excited during contraction of the circular muscle that occurs during spontaneous CMMCs. No activation of high-threshold rectal afferents was detected during CMMCs or intense contractile activity in naïve mouse colorectum.

  8. Effects of curcumin and captopril on the functions of kidney and nerve in streptozotocin-induced diabetic rats: role of angiotensin converting enzyme 1.

    PubMed

    Abd Allah, Eman S H; Gomaa, Asmaa M S

    2015-10-01

    Oxidative stress and inflammation are involved in the development and progression of diabetes and its complications. The renin-angiotensin system also plays an important role in the pathogenesis of diabetes and its complications. We hypothesized that curcumin and captopril would restore the kidney and nerve functions of diabetic rats through their angiotensin converting enzyme 1 (ACE1) inhibiting activity as well as their antioxidant and anti-inflammatory effects. Diabetes was induced by a single intraperitoneal injection of streptozotocin (100 mg·kg(-1) body weight). One week after induction of diabetes, rats were treated with 100 mg·kg(-1)·day(-1) curcumin or 50 mg·kg(-1)·day(-1) captopril orally for 6 weeks. Compared with diabetic control rats, curcumin- or captopril-treated diabetic rats had significantly improved blood glucose, lipid profile, kidney/body weight ratio, serum creatinine, blood urea nitrogen (BUN), and pain thresholds assessed by Von Frey filaments, hot plate test, and tail-flick test. Diabetic control rats showed increased levels of total peroxide, renal and neural tumor necrosis factor-α and interleukin-10, and renal ACE1 compared with nondiabetic rats. Although treatment with either curcumin or captopril restored the altered variables, captopril was more effective in reducing these variables. ACE1 was positively correlated with BUN and creatinine and negatively correlated with paw withdrawal threshold, hot plate reaction time, and tail-flick latency, suggesting a possible causal relationship. We conclude that curcumin and captopril protect against diabetic nephropathy and neuropathy by inhibiting ACE1 as well as oxidation and inflammation. These findings suggest that curcumin and captopril may have a role in the treatment of diabetic nephropathy and neuropathy.

  9. Diverse mechanisms for assembly of branchiomeric nerves.

    PubMed

    Cox, Jane A; Lamora, Angela; Johnson, Stephen L; Voigt, Mark M

    2011-09-15

    The formation of branchiomeric nerves (cranial nerves V, VII, IX and X) from their sensory, motor and glial components is poorly understood. The current model for cranial nerve formation is based on the Vth nerve, in which sensory afferents are formed first and must enter the hindbrain in order for the motor efferents to exit. Using transgenic zebrafish lines to discriminate between motor neurons, sensory neurons and peripheral glia, we show that this model does not apply to the remaining three branchiomeric nerves. For these nerves, the motor efferents form prior to the sensory afferents, and their pathfinding show no dependence on sensory axons, as ablation of cranial sensory neurons by ngn1 knockdown had no effect. In contrast, the sensory limbs of the IXth and Xth nerves (but not the Vth or VIIth) were misrouted in gli1 mutants, which lack hindbrain bmn, suggesting that the motor efferents are crucial for appropriate sensory axon projection in some branchiomeric nerves. For all four nerves, peripheral glia were the intermediate component added and had a critical role in nerve integrity but not in axon guidance, as foxd3 null mutants lacking peripheral glia exhibited defasciculation of gVII, gIX, and gX axons. The bmn efferents were unaffected in these mutants. These data demonstrate that multiple mechanisms underlie formation of the four branchiomeric nerves. For the Vth, sensory axons initiate nerve formation, for the VIIth the sensory and motor limbs are independent, and for the IXth/Xth the motor axons initiate formation. In all cases the glia are patterned by the initiating set of axons and are needed to maintain axon fasciculation. These results reveal that coordinated interactions between the three neural cell types in branchiomeric nerves differ according to their axial position.

  10. Auditory Evoked Potentials from the Frog Eighth Nerve

    DTIC Science & Technology

    1989-09-01

    ACCESSION NO. Brooks AFB, TX 78235-5301 62202F 7757 01 85 11. TITLE (I nclude Security Classification) (U) Auditory Evoked Potentials from the Frog Eighth...identify by block number) S FIELD jGROUP SUB-GROUP F6 07 Auditory Evoked Potential Eighth Nerve Frog 06 10 19. ABSTRACT (Continue on reverse if necessary...and identify by block number) A method for recording evoked potentials from the eighth nerve of frogs using midline and lateral electrodes is described

  11. 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

  12. 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.

  13. 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…

  14. 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

    Szolcsányi, J; Helyes, Z; Oroszi, G; Németh, J; Pintér, E

    1998-03-01

    1. 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 microg kg(-1), i.v.). 2. 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 microl 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. 3. Plasma extravasation in the knee joint in response to carrageenin (2%, 200 microl 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. 4. 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 microg 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. 5. 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 sciatic nerve

  15. Motif-role-fingerprints: the building-blocks of motifs, clustering-coefficients and transitivities in directed networks.

    PubMed

    McDonnell, Mark D; Yaveroğlu, Ömer Nebil; Schmerl, Brett A; Iannella, Nicolangelo; Ward, Lawrence M

    2014-01-01

    Complex networks are frequently characterized by metrics for which particular subgraphs are counted. One statistic from this category, which we refer to as motif-role fingerprints, differs from global subgraph counts in that the number of subgraphs in which each node participates is counted. As with global subgraph counts, it can be important to distinguish between motif-role fingerprints that are 'structural' (induced subgraphs) and 'functional' (partial subgraphs). Here we show mathematically that a vector of all functional motif-role fingerprints can readily be obtained from an arbitrary directed adjacency matrix, and then converted to structural motif-role fingerprints by multiplying that vector by a specific invertible conversion matrix. This result demonstrates that a unique structural motif-role fingerprint exists for any given functional motif-role fingerprint. We demonstrate a similar result for the cases of functional and structural motif-fingerprints without node roles, and global subgraph counts that form the basis of standard motif analysis. We also explicitly highlight that motif-role fingerprints are elemental to several popular metrics for quantifying the subgraph structure of directed complex networks, including motif distributions, directed clustering coefficient, and transitivity. The relationships between each of these metrics and motif-role fingerprints also suggest new subtypes of directed clustering coefficients and transitivities. Our results have potential utility in analyzing directed synaptic networks constructed from neuronal connectome data, such as in terms of centrality. Other potential applications include anomaly detection in networks, identification of similar networks and identification of similar nodes within networks. Matlab code for calculating all stated metrics following calculation of functional motif-role fingerprints is provided as S1 Matlab File.

  16. Motif-Role-Fingerprints: The Building-Blocks of Motifs, Clustering-Coefficients and Transitivities in Directed Networks

    PubMed Central

    McDonnell, Mark D.; Yaveroğlu, Ömer Nebil; Schmerl, Brett A.; Iannella, Nicolangelo; Ward, Lawrence M.

    2014-01-01

    Complex networks are frequently characterized by metrics for which particular subgraphs are counted. One statistic from this category, which we refer to as motif-role fingerprints, differs from global subgraph counts in that the number of subgraphs in which each node participates is counted. As with global subgraph counts, it can be important to distinguish between motif-role fingerprints that are ‘structural’ (induced subgraphs) and ‘functional’ (partial subgraphs). Here we show mathematically that a vector of all functional motif-role fingerprints can readily be obtained from an arbitrary directed adjacency matrix, and then converted to structural motif-role fingerprints by multiplying that vector by a specific invertible conversion matrix. This result demonstrates that a unique structural motif-role fingerprint exists for any given functional motif-role fingerprint. We demonstrate a similar result for the cases of functional and structural motif-fingerprints without node roles, and global subgraph counts that form the basis of standard motif analysis. We also explicitly highlight that motif-role fingerprints are elemental to several popular metrics for quantifying the subgraph structure of directed complex networks, including motif distributions, directed clustering coefficient, and transitivity. The relationships between each of these metrics and motif-role fingerprints also suggest new subtypes of directed clustering coefficients and transitivities. Our results have potential utility in analyzing directed synaptic networks constructed from neuronal connectome data, such as in terms of centrality. Other potential applications include anomaly detection in networks, identification of similar networks and identification of similar nodes within networks. Matlab code for calculating all stated metrics following calculation of functional motif-role fingerprints is provided as S1 Matlab File. PMID:25486535

  17. 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.

  18. Role of the trochlear nerve in eye abduction and frontal vision of the red-eared slider turtle (Trachemys scripta elegans).

    PubMed

    Dearworth, J R; Ashworth, A L; Kaye, J M; Bednarz, D T; Blaum, J F; Vacca, J M; McNeish, J E; Higgins, K A; Michael, C L; Skrobola, M G; Jones, M S; Ariel, M

    2013-10-15

    Horizontal head rotation evokes significant responses from trochlear motoneurons of turtle that suggests they have a functional role in abduction of the eyes like that in frontal-eyed mammals. The finding is unexpected given that the turtle is generally considered lateral-eyed and assumed to have eye movements instead like that of lateral-eyed mammals, in which innervation of the superior oblique muscle by the trochlear nerve (nIV) produces intorsion, elevation, and adduction (not abduction). Using an isolated turtle head preparation with the brain removed, glass suction electrodes were used to stimulate nIV with trains of current pulses. Eyes were monitored via an infrared camera with the head placed in a gimble to quantify eye rotations and their directions. Stimulations of nIV evoked intorsion, elevation, and abduction. Dissection of the superior oblique muscle identified lines of action and a location of insertion on the eye, which supported kinematics evoked by nIV stimulation. Eye positions in alert behaving turtles with their head extended were compared with that when their heads were retracted in the carapace. When the head was retracted, there was a reduction in interpupillary distance and an increase in binocular overlap. Occlusion of peripheral fields by the carapace forces the turtle to a more frontal-eyed state, perhaps the reason for the action of abduction by the superior oblique muscle. These findings support why trochlear motoneurons in turtle respond in the same way as abducens motoneurons to horizontal rotations, an unusual characteristic of vestibulo-ocular physiology in comparison with other mammalian lateral-eyed species.

  19. Imaging the ocular motor nerves.

    PubMed

    Ferreira, Teresa; Verbist, Berit; van Buchem, Mark; van Osch, Thijs; Webb, Andrew

    2010-05-01

    The ocular motor nerves (OMNs) comprise the oculomotor, trochlear and the abducens nerves. According to their course, they are divided into four or five anatomic segments: intra-axial, cisternal, cavernous and intra-orbital and, for the abducens nerve, an additional interdural segment. Magnetic resonance imaging is the imaging method of choice in the evaluation of the normal and pathologic ocular motor nerves. CT still plays a limited but important role in the evaluation of the intraosseous portions at the skull base and bony foramina. We describe for each segment of these cranial nerves, the normal anatomy, the most appropriate image sequences and planes, their imaging appearance and pathologic conditions. Magnetic resonance imaging with high magnetic fields is a developing and promising technique. We describe our initial experience with a Phillips 7.0T MRI scanner in the evaluation of the brainstem segments of the OMNs. As imaging becomes more refined, an understanding of the detailed anatomy is increasingly necessary, as the demand on radiology to diagnose smaller lesions also increases.

  20. 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

  1. [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.

  2. Tachy-Brady Arrhythmias: The Critical Role of Adenosine-induced Sino-Atrial Conduction Block in Post-Tachycardia Pauses

    PubMed Central

    Lou, Qing; Glukhov, Alexey V.; Hansen, Brian; Hage, Lori; Vargas-Pinto, Pedro; Billman, George E.; Carnes, Cynthia A.; Fedorov, Vadim V.

    2012-01-01

    Background In patients with sinoatrial nodal (SAN) dysfunction, atrial pauses lasting several seconds may follow rapid atrial pacing or paroxysmal tachycardia (tachy-brady arrhythmias). Clinical studies suggest that adenosine may play an important role in SAN dysfunction, but the mechanism remains unclear. Objective To define the mechanism of SAN dysfunction induced by the combination of adenosine and tachycardia. Methods We studied the mechanism of SAN dysfunction produced by a combination of adenosine and rapid atrial pacing in isolated coronary-perfused canine atrial preparations using high-resolution optical mapping (n=9). Sinus cycle length (SCL) and sinoatrial conduction time (SACT) were measured during adenosine (1–100μM) and 1μM DPCPX (A1 receptor antagonist, n=7) perfusion. Sinoatrial node recovery time was measured after one minute of “slow” pacing (3.3Hz) or tachypacing (7–9Hz). Results Adenosine significantly increased SCL (477±62 vs. 778±114 ms, p<0.01), and SACT during sinus rhythm (41±11 vs. 86±16 ms, p<0.01) dose-dependently. Adenosine dramatically affected SACT of the first SAN beat after tachypacing (41±5 vs. 221±98ms, p<0.01). Moreover, at high concentrations of adenosine (10–100μM), termination of tachypacing or atrial flutter/fibrillation produced atrial pauses of 4.2±3.4 seconds (n=5) due to conduction block between the SAN and atria, despite a stable SAN intrinsic rate. Conduction block was preferentially related to depressed excitability in SAN conduction pathways. Adenosine-induced changes were reversible upon washout or DPCPX treatment. Conclusions These data directly demonstrate that adenosine contributes to post-tachycardia atrial pauses through SAN exit block rather than slowed pacemaker automaticity. Thus, these data suggest an important modulatory role of adenosine in tachy-brady syndrome. PMID:22985657

  3. Granulocyte macrophage colony stimulating factor produced in lesioned peripheral nerves induces the up-regulation of cell surface expression of MAC-2 by macrophages and Schwann cells

    PubMed Central

    1996-01-01

    Peripheral nerve injury is followed by Wallerian degeneration which is characterized by cellular and molecular events that turn the degenerating nerve into a tissue that supports nerve regeneration. One of these is the removal, by phagocytosis, of myelin that contains molecules which inhibit regeneration. We have recently documented that the scavenger macrophage and Schwann cells express the galactose- specific lectin MAC-2 which is significant to myelin phagocytosis. In the present study we provide evidence for a mechanism leading to the augmented expression of cell surface MAC-2. Nerve lesion causes noneuronal cells, primarily fibroblasts, to produce the cytokine granulocyte macrophage-colony stimulating factor (GM-CSF). In turn, GM- CSF induces Schwann cells and macrophages to up-regulate surface expression of MAC-2. The proposed mechanism is based on the following novel observations. GM-CSF mRNA was detected by PCR in in vitro and in vivo degenerating nerves, but not in intact nerves. The GM-CSF molecule was detected by ELISA in medium conditioned by in vitro and in vivo degenerating peripheral nerves as of the 4th h after injury. GM-CSF activity was demonstrated by two independent bioassays, and repressed by activity blocking antibodies. Significant levels of GM-CSF were produced by nerve derived fibroblasts, but neither by Schwann cells nor by nerve derived macrophages. Mouse rGM-CSF enhanced MAC-2 production in nerve explants, and up-regulated cell surface expression of MAC-2 by Schwann cells and macrophages. Interleukin-1 beta up-regulated GM-CSF production thus suggesting that injury induced GM-CSF production may be mediated by interleukin-1 beta. Our findings highlight the fact that fibroblasts, by producing GM-CSF and thereby affecting macrophage and Schwann function, play a significant role in the cascade of molecular events and cellular interactions of Wallerian degeneration. PMID:8601605

  4. Phenol block for hip flexor muscle spasticity under ultrasonic monitoring.

    PubMed

    Koyama, H; Murakami, K; Suzuki, T; Suzaki, K

    1992-11-01

    Hip flexor spasticity, which is often associated with central nervous system (CNS) diseases, is a major impediment in rehabilitation. In order to cope with this problem, lumbar nerve blocking techniques developed by Meelhuysen and major and minor psoas muscle blocking techniques developed by Awad have been used in combination with physical therapies. Based on these techniques, we conducted major and minor psoas muscle phenol block (motor point block or intramuscular nerve block) under ultrasonic monitoring. Phenol block was conducted in nine patients with cerebral infarction (13 blocking procedures) and three with spinal cord injuries (six blocking procedures) while keeping them in a lateral position with the operation side upside. The beginning of the femoral nerves and part of the lumbar artery were visualized by ultrasound in some patients. As a result of the improvement of hip flexor spasticity, the range of hip joint motion (determined by the Mundale technique, prone hip extension and Thomas test) improved shortly after blocking. When physical therapy was conducted after blocking, improvement of skin care management was observed in eight cases, ability to keep in a stable sitting position in nine, improvement of a standing posture in three, increases in the ability to walk in two and alleviation of pain in three. Although nerve block is reported to result in hematoma, decreases in muscle force, pain, cystic/rectal disorders and hypogonadism, we have observed no such complication in our patients.

  5. 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)

  6. 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.

  7. 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.

  8. Study on Variant Anatomy of Sciatic Nerve

    PubMed Central

    V, Sangeetha

    2014-01-01

    Introduction: Sciatic Nerve (SN) is the nerve of the posterior compartment of thigh formed in the pelvis from the ventral rami of the L4 to S3 spinal nerves. It leaves the pelvis via the greater sciatic foramen below piriformis and divides into Common Peroneal Nerve (CPN) and Tibial Nerve (TN) at the level of the upper angle of the popliteal fossa. Higher division of the sciatic nerve is the most common variation where the TN and CPN may leave the pelvis through different routes. Such variation may lead to compression of the nerve and lead to Non-discogenic sciatica. Materials and Methods: Fifty lower limbs were used for the study from Department of Anatomy, J.J.M.M.C Davangere, Karnataka, India. Observation and Results: In our study on 25 cadavers (50 lower limbs), we have observed 4 (8 %) lower limbs high division of sciatic nerve was noted. High division of sciatic nerve in the back of thigh was noted in one specimen (2%), while high division within the pelvis was noted in 3 specimens (6%), while in 46 (92%) it occurred outside the pelvis. Conclusion: Knowledge regarding such variation and differences in the course of SN is important for the surgeons to plan for various surgical interventions pertaining to the gluteal region. The variant anatomy of SN may cause piriformis syndrome and failure of SN block. Hence present study is undertaken to know the level of division, exit, course, relationship to piriformis and variations in the branching pattern of SN. PMID:25302181

  9. Homeostatic response to blocking cell division in Drosophila imaginal discs: Role of the Fat/Dachsous (Ft/Ds) pathway.

    PubMed

    Montes, Antonio J; Morata, Ginés

    2017-03-11

    One major problem in developmental biology is the identification of the mechanisms that control the final size of tissues and organs. We are addressing this issue in the imaginal discs of Drosophila by analysing the response to blocking cell division in large domains in the wing and leg discs. The affected domains may be zones of restricted lineage like compartments, or zones of open lineage that may integrate cells from the surrounding territory. Our results reveal the existence of a powerful homeostatic mechanism that can compensate for gross differences in growth rates and builds structures of normal size. This mechanism functions at the level of whole discs, inducing additional cell proliferation to generate the cells that populate the cell division-arrested territory and generating an active recruitment process to integrate those cells. The activation of this response mechanism is mediated by alterations in the normal activity of PCP genes of the Fat/Ds system: in discs mutant for dachs, ds or four jointed the response mechanism is not activated.

  10. Optic Nerve Pit

    MedlinePlus

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

  11. [Multifocal-motor neuropathy and motor neuropathy with multifocal conduction block (Lewis-Sumner syndrome)].

    PubMed

    Finsterer, J; Mamoli, B

    1995-01-01

    Multifocal motor neuropathy, which mimics lower motor neuron disease, is a rare and curious demyelinating neuropathy characterised by slowly progressive, asymmetric limb weakness within the distribution of individual peripheral nerves, wasting, cramps, fasciculations and rare sensory involvement, but without upper motor neuron signs. The cardinal feature and primary pathophysiological basis for the weakness is the multifocal motor conduction block which remains stable for years at the same site and is confined to motor axons. It is defined as > 50% reduction in both the CMAP and the negative peak area on proximal stimulation, as compared with the distal stimulus response without any change in the negative peak duration. Nerves at the site of the conduction block show demyelination, endoneural edema, rudimentary onion bulbs and lymphocytic inflammation. Sensory nerves may show mild demyelination, axon loss and lymphocytic inflammation. The majority of patients shows elevated titers of anti-glycolipid antibodies, which may block the Na+ channels, produce demyelination or interfere with remyelination. However, their role in the pathogenesis of multifocal motor neuropathy remains uncertain. Multifocal motor neuropathy is regarded as the predominantly motor variant of chronic inflammatory demyelinating polyneuropathy and can be treated best with immunoglobulins and cyclophosphamide.

  12. Ondansetron reverses anti-hypersensitivity from clonidine in rats following peripheral nerve injury: Role of γ-amino butyric acid in α2-adrenoceptor and 5-HT3 serotonin receptor analgesia

    PubMed Central

    Hayashida, Ken-ichiro; Kimura, Masafumi; Yoshizumi, Masaru; Hobo, Shotaro; Obata, Hideaki; Eisenach, James C.

    2012-01-01

    Introduction Monoaminergic pathways, impinging an α2-adrenoceptors and 5-HT3 serotonin receptors, modulate nociceptive transmission, but their mechanisms and interactions after neuropathic injury are unknown. Here we examine these interactions in rodents after nerve injury. Methods Male Sprague-Dawley rats following L5-L6 spinal nerve ligation (SNL) were used for either behavioral testing, in vivo microdialysis for γ-amino butyric acid (GABA) and acetylcholine release, or synaptosome preparation for GABA release. Results Intrathecal administration of the α2-adrenoceptor agonist (clonidine) and 5-HT3 receptor agonist (chlorophenylbiguanide) reduced hypersensitivity in SNL rats via GABA receptor-mediated mechanisms. Clonidine increased GABA and acetylcholine release in vivo in the spinal cord of SNL rats but not in normal rats. Clonidine-induced spinal GABA release in SNL rats was blocked by α2-adrenergic and nicotinic cholinergic antagonists. The 5-HT3 receptor antagonist ondansetron decreased and chlorophenylbiguanide increased spinal GABA release in both normal and SNL rats. In synaptosomes from the spinal dorsal horn of SNL rats, pre-synaptic GABA release was increased by nicotinic agonists and decreased by muscarinic and α2-adrenergic agonists. Spinally administered ondansetron significantly reduced clonidine-induced anti-hypersensitivity and spinal GABA release in SNL rats. Conclusion These results suggest that spinal GABA contributes to anti-hypersensitivity from intrathecal α2-adrenergic and 5-HT3 receptor agonists in the neuropathic pain state, that cholinergic neuroplasticity after nerve injury is critical for α2-adrenoceptor-mediated GABA release, and that blockade of spinal 5-HT3 receptors reduces α2-adrenoceptor-mediated anti-hypersensitivity via reducing total GABA release. PMID:22722575

  13. The cardioprotective effects of fish oil during pressure overload are blocked by high fat intake: role of cardiac phospholipid remodeling.

    PubMed

    Shah, Keyur B; Duda, Monika K; O'Shea, Karen M; Sparagna, Genevieve C; Chess, David J; Khairallah, Ramzi J; Robillard-Frayne, Isabelle; Xu, Wenhong; Murphy, Robert C; Des Rosiers, Christine; Stanley, William C

    2009-09-01

    Supplementation with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from fish oil may prevent development of heart failure through alterations in cardiac phospholipids that favorably impact inflammation and energy metabolism. A high-fat diet may block these effects in chronically stressed myocardium. Pathological left ventricle (LV) hypertrophy was generated by subjecting rats to pressure overload by constriction of the abdominal aorta. Animals were fed: (1) standard diet (10% of energy from fat), (2) standard diet with EPA+DHA (2.3% of energy intake as EPA+DHA), (3) high fat (60% fat); or (4) high fat with EPA+DHA. Pressure overload increased LV mass by approximately 40% in both standard and high-fat diets without fish oil. Supplementation with fish oil increased their incorporation into cardiac phospholipids, and decreased the proinflammatory fatty acid arachidonic acid and urine thromboxane B(2) with both the standard and high-fat diet. Linoleic acid and tetralinoloyl cardiolipin (an essential mitochondrial phospholipid) were decreased with pressure overload on standard diet, which was prevented by fish oil. Animals fed high-fat diet had decreased linoleic acid and tetralinoloyl cardiolipin regardless of fish oil supplementation. Fish oil limited LV hypertrophy on the standard diet, and prevented upregulation of fetal genes associated with heart failure (myosin heavy chain-beta and atrial natriuetic factor). These beneficial effects of fish oil were absent in animals on the high-fat diet. In conclusion, whereas treatment with EPA+DHA prevented tetralinoloyl cardiolipin depletion, LV hypertrophy, and abnormal genes expression with pressure overload, these effects were absent with a high-fat diet.

  14. The role of Gd-enhanced three-dimensional MRI fast low-angle shot (FLASH) in the evaluation of symptomatic lumbosacral nerve roots.

    PubMed

    Kikkawa, I; Sugimoto, H; Saita, K; Ookami, H; Nakama, S; Hoshino, Y

    2001-01-01

    In the field of lumbar spine disorders, three-dimensional (3-D) magnetic resonance imaging (MRI) can clearly depict a lumbar nerve root from the distal region to the dorsal root ganglion. In this study, we used a gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) enhanced-three-dimensional (3-D) fast low-angle shot (FLASH) sequence when examining lumbosacral disorders. The subjects were 33 patients (14 men and 19 women) in whom lumbosacral neural compression had been diagnosed clinically. Twenty-one patients had lumbar disc herniation, 11 had lumbar spinal stenosis, and 1 had lumbar radiculopathy caused by rheumatoid arthritis. Five subjects with low back pain were also studied as a control group. In all patients and in all 5 of the controls, the dorsal root ganglion of every root was enhanced clearly. There was no root enhancement in the 5 controls. Enhancement of the symptomatic nerve roots, caused by compression, was found in 11 of the 33 patients. All 11 patients had radiculopathy, and muscle weakness was more frequent in patients with enhanced nerve roots than in those without enhancement. There was no enhancement of the cauda equina, even in the patients with cauda syndrome. The enhancement effect may reflect some pathological condition of the compressed nerve root and needs to be studied further.

  15. Block of cyclic nucleotide-gated channels by tetracaine derivatives: role of apolar interactions at two distinct locations

    PubMed Central

    Strassmaier, Timothy; Kirk, Sarah R.; Banerji, Tapasree; Karpen, Jeffrey W.

    2008-01-01

    A series of new tetracaine derivatives was synthesized to explore the effects of hydrophobic character on blockade of cyclic nucleotide-gated (CNG) channels. Increasing the hydrophobicity at either of two positions on the tetracaine scaffold, the tertiary amine or the butyl tail, yields blockers with increased potency. However, shape also plays an important role. While gradual increases in length of the butyl tail lead to increased potency, substitution of the butyl tail with branched alkyl or cyclic groups is deleterious. PMID:18055205

  16. 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

  17. The effect of NGF depletion on the neurotropic influence exerted by the distal stump following nerve transection.

    PubMed Central

    Doubleday, B; Robinson, P P

    1995-01-01

    Following nerve section, regenerating axons from the proximal stump grow preferentially towards the distal stump. It has been postulated that this may result from the release of a neurotropic factor. To investigate whether the protein nerve growth factor (NGF) plays such a role, we immunised adult rats against NGF and examined the effect on regeneration of sectioned nerves through Y-shaped silastic tubes towards either the distal stump or an empty arm. Regeneration through the tubes was assessed electrophysiologically and the number of myelinated and nonmyelinated fibres at different sites was quantified using electron microscopy. There was electrophysiological evidence of regeneration towards the distal nerve stump in all the animals and there was no significant difference between the immunised and control animals in the size of compound action potential (CAP) ratios. Histologically, the majority of axons were found to have regenerated towards the distal nerve stump in 9/10 of the control animals and 7/9 of the immunised animals and there was no significant difference between the two groups in the numbers of regenerating myelinated or unmyelinated axons. However, in the immunised animals both myelinated and unmyelinated axons were slightly but significantly smaller and the myelin sheaths were thinner than in the control animals. In 2 immunised animals and none of the controls a small CAP was recorded while stimulating distal to the 'empty arm' and the presence of a small number of myelinated and unmyelinated axons was confirmed histologically. We conclude that as depletion of NGF does not block the preferential growth of regenerating axons towards the distal nerve stump it does not play the major neurotropic role in nerve regeneration. The reduction in size and myelin thickness of the regenerated axons after immunisation confirms the neurotrophic effects of NGF. Images Fig. 1 Fig. 2 Fig. 4 PMID:7559132

  18. 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

  19. Structure-Activity Relationship of Nerve-Highlighting Fluorophores

    PubMed Central

    Gibbs, Summer L.; Xie, Yang; Goodwill, Haley L.; Nasr, Khaled A.; Ashitate, Yoshitomo; Madigan, Victoria J.; Siclovan, Tiberiu M.; Zavodszky, Maria; Tan Hehir, Cristina A.; Frangioni, John V.

    2013-01-01

    Nerve damage is a major morbidity associated with numerous surgical interventions. Yet, nerve visualization continues to challenge even the most experienced surgeons. A nerve-specific fluorescent contrast agent, especially one with near-infrared (NIR) absorption and emission, would be of immediate benefit to patients and surgeons. Currently, there are only three classes of small molecule organic fluorophores that penetrate the blood nerve barrier and bind to nerve tissue when administered systemically. Of these three classes, the distyrylbenzenes (DSBs) are particularly attractive for further study. Although not presently in the NIR range, DSB fluorophores highlight all nerve tissue in mice, rats, and pigs after intravenous administration. The purpose of the current study was to define the pharmacophore responsible for nerve-specific uptake and retention, which would enable future molecules to be optimized for NIR optical properties. Structural analogs of the DSB class of small molecules were synthesized using combinatorial solid phase synthesis and commercially available building blocks, which yielded more than 200 unique DSB fluorophores. The nerve-specific properties of all DSB analogs were quantified using an ex vivo nerve-specific fluorescence assay on pig and human sciatic nerve. Results were used to perform quantitative structure-activity relationship (QSAR) modeling and to define the nerve-specific pharmacophore. All DSB analogs with positive ex vivo fluorescence were tested for in vivo nerve specificity in mice to assess the effect of biodistribution and clearance on nerve fluorescence signal. Two new DSB fluorophores with the highest nerve to muscle ratio were tested in pigs to confirm scalability. PMID:24039960

  20. Optic Nerve Elongation

    PubMed Central

    Alvi, Aijaz; Janecka, Ivo P.; Kapadia, Silloo; Johnson, Bruce L.; McVay, William

    1996-01-01

    The length of the optic nerves is a reflection of normal postnatal cranio-orbital development. Unilateral elongation of an optic nerve has been observed in two patients with orbital and skull base neoplasms. In the first case as compared to the patient's opposite, normal optic nerve, an elongated length of the involved optic nerve of 45 mm was present. The involved optic nerve in the second patient was 10 mm longer than the normal opposite optic nerve. The visual and extraocular function was preserved in the second patient. The first patient had only light perception in the affected eye. In this paper, the embryology, anatomy, and physiology of the optic nerve and its mechanisms of stretch and repair are discussed. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10Figure 11Figure 13 PMID:17170975

  1. [Mobile ISCR elements: structure, functions, and role in the emergence, increasing and spreading of blocks of bacterial genes of multiple antibiotic resistance].

    PubMed

    Il'ina, T S

    2012-01-01

    The recently discovered method of horizontal distribution of bacterial genes with atypical ISCR sequences is reviewed using an example of drug resistance genes. The adjacent DNA segment mobilization is provided by the transposition of such elements, including rolling circle replication, formation of autonomous nonreplicable circular structures, and homological recombination. The gene distribution capacity with the ISCR elements is more significant than the capacity of transposons and integrons, thereby providing formation of groups of mobile genes, including antibiotic-resistance genes of pathogenic bacteria. The structure and functions of the ISCR elements were discussed together with their similarity and dissimilarity with the group of IS91-similar elements and their role in the emergence of blocks of bacterial genes encoding of multiple antibiotic resistance and their contribution to evolution of bacterial and plasmid genes.

  2. Carbon dioxide laser-assisted nerve repair: effect of solder and suture material on nerve regeneration in rat sciatic nerve.

    PubMed

    Menovsky, Tomas; Beek, Johan F

    2003-01-01

    In order to further improve and explore the role of lasers for nerve reconstruction, this study was designed to investigate regeneration of sharply transected peripheral nerves repaired with a CO(2) milliwatt laser in combination with three different suture materials and a bovine albumin protein solder as an adjunct to the welding process. Unilateral sciatic nerve repair was performed in 44 rats. In the laser group, nerves were gently apposed, and two stay sutures (10-0 nylon, 10-0 polyglycolic acid, or 25 microm stainless steel) were placed epi/perineurially. Thereafter, the repair site was fused at 100 mW with pulses of 1.0 s. In the subgroup of laser-assisted nerve repair (LANR), albumen was used as a soldering agent to further reinforce the repair site. The control group consisted of nerves repaired by conventional microsurgical suture repair (CMSR), using 4-6 10-0 nylon sutures. Evaluation was performed at 1 and 6 weeks after surgery, and included qualitative and semiquantitative light microscopy. LANR performed with a protein solder results in a good early peripheral nerve regeneration, with an optimal alignment of nerve fibers and minimal connective tissue proliferation at the repair site. All three suture materials produced a foreign body reaction; the least severe was with polyglycolic acid sutures. CMSR resulted in more pronounced foreign-body granulomas at the repair site, with more connective-tissue proliferation and axonal misalignment. Furthermore, axonal regeneration in the distal nerve segment was better in the laser groups. Based on these results, CO(2) laser-assisted nerve repair with soldering in combination with absorbable sutures has the potential of allowing healing to occur with the least foreign-body reaction at the repair site. Further experiments using this combination are in progress.

  3. Assessment of nerve morphology in nerve activation during electrical stimulation

    NASA Astrophysics Data System (ADS)

    Gomez-Tames, Jose; Yu, Wenwei

    2013-10-01

    The distance between nerve and stimulation electrode is fundamental for nerve activation in Transcutaneous Electrical Stimulation (TES). However, it is not clear the need to have an approximate representation of the morphology of peripheral nerves in simulation models and its influence in the nerve activation. In this work, depth and curvature of a nerve are investigated around the middle thigh. As preliminary result, the curvature of the nerve helps to reduce the simulation amplitude necessary for nerve activation from far field stimulation.

  4. Pleiotrophin and peripheral nerve injury.

    PubMed

    Jin, Li; Jianghai, Chen; Juan, Liu; Hao, Kang

    2009-10-01

    The proto-oncogene pleiotrophin, disc