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Sample records for multimodal experimental pain

  1. Pain Management in Pregnancy: Multimodal Approaches

    PubMed Central

    Shah, Shalini; Banh, Esther T.; Koury, Katharine; Bhatia, Gaurav; Nandi, Roneeta; Gulur, Padma

    2015-01-01

    Nonobstetrical causes of pain during pregnancy are very common and can be incapacitating if not treated appropriately. Recent reports in the literature show that a significant percentage of pregnant women are treated with opioids during pregnancy. To address common pain conditions that present during pregnancy and the available pharmacological and nonpharmacological treatment options, for each of the pain conditions identified, a search using MEDLINE, PubMed, Embase, and Cochrane databases was performed. The quality of the evidence was evaluated in the context of study design. This paper is a narrative summary of the results obtained from individual reviews. There were significant disparities in the studies in terms of design, research and methodology, and outcomes analyzed. There is reasonable evidence available for pharmacological approaches; however, these are also associated with adverse events. Evidence for nonpharmacological approaches is limited and hence their efficacy is unclear, although they do appear to be primarily safe. A multimodal approach using a combination of nonpharmacological and pharmacological options to treat these pain conditions is likely to have the most benefit while limiting risk. Research trials with sound methodology and analysis of outcome data are needed. PMID:26448875

  2. Determining Pain Detection and Tolerance Thresholds Using an Integrated, Multi-Modal Pain Task Battery

    PubMed Central

    Hay, Justin L.; Okkerse, Pieter; van Amerongen, Guido; Groeneveld, Geert Jan

    2016-01-01

    Human pain models are useful in the assessing the analgesic effect of drugs, providing information about a drug's pharmacology and identify potentially suitable therapeutic populations. The need to use a comprehensive battery of pain models is highlighted by studies whereby only a single pain model, thought to relate to the clinical situation, demonstrates lack of efficacy. No single experimental model can mimic the complex nature of clinical pain. The integrated, multi-modal pain task battery presented here encompasses the electrical stimulation task, pressure stimulation task, cold pressor task, the UVB inflammatory model which includes a thermal task and a paradigm for inhibitory conditioned pain modulation. These human pain models have been tested for predicative validity and reliability both in their own right and in combination, and can be used repeatedly, quickly, in short succession, with minimum burden for the subject and with a modest quantity of equipment. This allows a drug to be fully characterized and profiled for analgesic effect which is especially useful for drugs with a novel or untested mechanism of action. PMID:27166581

  3. Experimental verification of MMI by singlemode-multimode-singlemode and multimode-singlemode structures

    NASA Astrophysics Data System (ADS)

    Majumder, Saikat; Ghosh, Amarnath; Roy, Bapita; Chakraborty, Rajib

    2015-06-01

    Multimode Interference (MMI) based on self imaging phenomenon is investigated using matrix approach. Experimentally MMI is verified using singlemode-multimode-singlemode and multimodesinglemode structures of optical fiber. The results obtained are also verified by BPM technique.

  4. Experimental human pain models in gastro-esophageal reflux disease and unexplained chest pain

    PubMed Central

    Drewes, Asbjørn Mohr; Arendt-Nielsen, Lars; Funch-Jensen, Peter; Gregersen, Hans

    2006-01-01

    Methods related to experimental human pain research aim at activating different nociceptors, evoke pain from different organs and activate specific pathways and mechanisms. The different possibilities for using mechanical, electrical, thermal and chemical methods in visceral pain research are discussed with emphasis of combinations (e.g., the multimodal approach). The methods have been used widely in assessment of pain mechanisms in the esophagus and have contributed to our understanding of the symptoms reported in these patients. Hence abnormal activation and plastic changes of central pain pathways seem to play a major role in the symptoms in some patients with gastro-esophageal reflux disease and in patients with functional chest pain of esophageal origin. These findings may lead to an alternative approach for treatment in patients that does not respond to conventional medical or surgical therapy. PMID:16718803

  5. Towards multimodal nonlinear optical tomography - experimental methodology

    NASA Astrophysics Data System (ADS)

    Vogler, N.; Medyukhina, A.; Latka, I.; Kemper, S.; Böhm, M.; Dietzek, B.; Popp, J.

    2011-08-01

    All-optical microspectroscopic and tomographic tools reveal great potential for clinical dermatologic diagnostics, i.e., investigation of human skin and skin diseases. While optical-coherence tomography has been complemented by two-photon fluorescence tomography and second-harmonic generation tomography, a joint study of various nonlinear optical microspectroscopies, i.e., application of the recently developed multimodal imaging approach, to sizable human-tissue samples has not been evaluated up to now. Here, we present such multimodal approach combining different nonlinear optical contrast mechanisms for imaging, namely two-photon excited fluorescence (TPF), second-harmonic generation (SHG), and coherent anti-Stokes Raman scattering (CARS) into a joint microscopic experiment. We show the potential of imaging large skin areas and discuss the information obtained in a case study comparing normal skin and keloid tissue.

  6. Best evidence in multimodal pain management in spine surgery and means of assessing postoperative pain and functional outcomes.

    PubMed

    Devin, Clinton J; McGirt, Matthew J

    2015-06-01

    Multimodal approaches to pain management have arisen with the goal of improving postoperative pain and reducing opioid analgesic use. We performed a comprehensive literature review to determine grades of recommendation for commonly used agents in multimodal pain management and provide a best practice guideline. To evaluate common drugs used in multimodal treatment of pain, a search was performed on English language publications on Medline (PubMed; National Library of Medicine, Bethesda, MD, USA). Manuscripts were rated as Level I-V according to the North American Spine Society's (NASS) standardized levels of evidence tables. Grades of recommendation were assigned for each drug based on the NASS Clinical Guidelines for Multidisciplinary Spine Care. There is good (Grade A) evidence gabapentinoids, acetaminophen, neuraxial blockade and extended-release local anesthetics reduce postoperative pain and narcotic requirements. There is fair (Grade B) evidence that preemptive analgesia and nonsteroidal anti-inflammatory drugs (NSAID) result in reduced postoperative pain. There is insufficient and/or conflicting (Grade I) evidence that muscle relaxants and ketamine provide a significant reduction in postoperative pain or narcotic usage. There is fair (Grade B) evidence that short-term use of NSAID result in no long-term reduction in bone healing or fusion rates. Comprehensive assessment of the effectiveness of perioperative pain control can be accomplished through the use of validated measures. Multimodal pain management protocols have consistently been demonstrated to allow for improved pain control with less reliance on opioids. There is good quality evidence that supports many of the common agents utilized in multimodal therapy, however, there is a lack of evidence regarding optimal postoperative protocols or pathways. PMID:25766366

  7. Benefits of a Multimodal Regimen for Postsurgical Pain Management in Colorectal Surgery

    PubMed Central

    Beck, David E.; Margolin, David A.; Babin, Sheena Farragut; Russo, Christine Theriot

    2015-01-01

    Background Postoperative pain management is a major concern and a significant component of postoperative care pathways for surgery patients. Methods We performed a retrospective medical record review of 233 consecutive patients undergoing major colorectal surgery from October 2011 to January 2013 at an academic medical center. All patients were managed with similar enhanced recovery pathways; 66 patients received multimodal postsurgical pain management that included liposomal bupivacaine intraoperatively, and 167 patients received conventional pain management with intravenous opioids. Comparisons were made using t test and chi-square analysis with StatView (SAS Institute Inc.). Results Patients receiving multimodal pain management with liposomal bupivacaine injected in the surgical site at the end of major colorectal procedures had lower postoperative pain scores and used significantly less opioids at 12, 24, 36, 48, 60, and 72 hours (P=0.03). Patients in the multimodal group also had a significantly decreased risk of opioid-related adverse events, with decreased use of antipruritic medications and antiemetic medications postoperatively. A significant decrease in length of postoperative hospital stay was seen in the multimodal group (7.2 vs 9.0 days, P=0.04). Conclusion The use of multimodal pain management including liposomal bupivacaine during major colorectal surgeries improved postoperative outcomes, decreased lengths of stay, and increased bed availability. PMID:26730224

  8. Multimodal MRI characterization of experimental subarachnoid hemorrhage.

    PubMed

    Sun, Y; Shen, Q; Watts, L T; Muir, E R; Huang, S; Yang, G-Y; Suarez, J I; Duong, T Q

    2016-03-01

    Subarachnoid hemorrhage (SAH) is associated with significant morbidity and mortality. We implemented an in-scanner rat model of mild SAH in which blood or vehicle was injected into the cistern magna, and applied multimodal MRI to study the brain prior to, immediately after (5min to 4h), and upto 7days after SAH. Vehicle injection did not change arterial lumen diameter, apparent diffusion coefficient (ADC), T2, venous signal, vascular reactivity to hypercapnia, or foot-fault scores, but mildly reduce cerebral blood flow (CBF) up to 4h, and open-field activity up to 7days post injection. By contrast, blood injection caused: (i) vasospasm 30min after SAH but not thereafter, (ii) venous abnormalities at 3h and 2days, delayed relative to vasospasm, (iii) reduced basal CBF and to hypercapnia 1-4h but not thereafter, (iv) reduced ADC immediately after SAH but no ADC and T2 changes on days 2 and 7, and (v) reduced open-field activities in both SAH and vehicle animals, but no significant differences in open-field activities and foot-fault tests between groups. Mild SAH exhibited transient and mild hemodynamic disturbances and diffusion changes, but did not show apparent ischemic brain injury nor functional deficits. PMID:26708744

  9. Vicarious pain while observing another in pain: an experimental approach

    PubMed Central

    Vandenbroucke, S.; Crombez, G.; Van Ryckeghem, D. M. L.; Brass, M.; Van Damme, S.; Goubert, L.

    2013-01-01

    Objective: This study aimed at developing an experimental paradigm to assess vicarious pain experiences. We further explored the putative moderating role of observer's characteristics such as hypervigilance for pain and dispositional empathy. Methods: Two experiments are reported using a similar procedure. Undergraduate students were selected based upon whether they reported vicarious pain in daily life, and categorized into a pain responder group or a comparison group. Participants were presented a series of videos showing hands being pricked whilst receiving occasionally pricking (electrocutaneous) stimuli themselves. In congruent trials, pricking and visual stimuli were applied to the same spatial location. In incongruent trials, pricking and visual stimuli were in the opposite spatial location. Participants were required to report on which location they felt a pricking sensation. Of primary interest was the effect of viewing another in pain upon vicarious pain errors, i.e., the number of trials in which an illusionary sensation was reported. Furthermore, we explored the effect of individual differences in hypervigilance to pain, dispositional empathy and the rubber hand illusion (RHI) upon vicarious pain errors. Results: Results of both experiments indicated that the number of vicarious pain errors was overall low. In line with expectations, the number of vicarious pain errors was higher in the pain responder group than in the comparison group. Self-reported hypervigilance for pain lowered the probability of reporting vicarious pain errors in the pain responder group, but dispositional empathy and the RHI did not. Conclusion: Our paradigm allows measuring vicarious pain experiences in students. However, the prevalence of vicarious experiences of pain is low, and only a small percentage of participants display the phenomenon. It remains however unknown which variables affect its occurrence. PMID:23781187

  10. Liposomal bupivacaine in hallux valgus surgery: a multimodal pain management adjunct.

    PubMed

    Huh, Jeannie; Parekh, Selene G

    2014-01-01

    The objective of this study was to review the use of liposomal bupivacaine as a multimodal pain management adjunct following hallux valgus surgery. The study was a prospective review of a consecutive series of patients who underwent hallux valgus surgery and received liposomal bupivacaine. From postoperative day (POD) 1 to 4, pain scores, number of narcotic rescue pills used, and adverse events were recorded. Wound complications, narcotic refills, and unscheduled clinic and emergency room (ER) visits or hospital admissions for pain were also recorded. The average pain rating was <3.4 (±2.4) during POD 1 to 4. Four patients (28.6%) reported never experiencing pain (Numeric Rating Scale ≤1). Seventy-one percent used narcotic rescue pills on POD 1. There were no unscheduled office or ER visits or hospital admissions. One adverse event and one wound complication occurred. Liposomal bupivacaine may be a safe and useful adjunct in a multimodal pain regimen for patients undergoing hallux valgus surgery. More rigorous studies are needed to determine its efficacy, safety profile, and cost-effectiveness compared to placebo. PMID:25785470

  11. [Assessment of pain relief in patients receiving different variants of multimodal analgesia after major gynecological surgery].

    PubMed

    Timerbaev, V H; Smimova, O V; Genov, P G; Olejnikova, O N; Rebrova, O Yu

    2014-01-01

    The major gynecology surgery generally results in severe postoperative pain. Currently multimodal analgesia concept is widely used for the aim of postoperative pain relief optimization. According to this theory it is worth using the medication with different mechanism in order to increase analgesia qualify, decrease analgesic consumption and avoid adverse reaction. Unfortunately the surveys recently conducted have been pointed out the postoperative analgesia quality is still insufficient despite of using the concept mentioned above. One way to solve the problem is appearing in daily practice nefopam--centrally acting non-opioid analgesic that inhibits reuptake of serotonin, norepinephrine, and dopamine and also mitigates glutamatergic neurotransmission. In this trial we tried to assess the postoperative daily used analgesia quality and potency of preemptive multimodal analgesia model consisted of nefopam, ketoprofen, paracetamol and morphine.

  12. Obesity effect on a multimodal physiotherapy program for low back pain suffers: patient reported outcome

    PubMed Central

    2013-01-01

    Background Several studies have linked obesity to the increased likelihood of lower back pain, but there are no studies focussing on the effectiveness of a multimodal physiotherapy programme (MPP) in obese subjects who suffer from chronic non-specific lower back pain (CNLBP). The aim of this study was to compare the effectiveness of an MPP in obese (G1) (body mass index (BMI):≥30) and non-obese (G2) (BMI:<30) patients with CNLBP. Methods A quasi-experimental study with pre- and post-intervention evaluations of an MPP (lasting 8 weeks) was conducted on obese and non-obese patients with CNLBP. A total of 53 people were included in the study: G1, composed of 19 patients (10 men and 9 women) with a BMI of 33.75 and a mean age of 52.94 years, and G2, composed of 34 patients (18 men and 16 women) with a mean age of 49.19 years and an average BMI of 25.56. All patients were measured to calculate pre-intervention (baseline) and post-intervention (8 weeks) changes in disability (RMQ) and health related quality of life in physical and mental health component state of SF12 and quality of life (EQ-5D and EQ-VAS). Results Post-intervention, non-obese group shown significant high improve than obese group in disability (RMQ: 4.00), physical component state of SF-12: (-7.26) and quality of life (EQ-VAS.: -10.49). Conclusions In patients with CNLBP, a BMI more than or equal to 30 minimises the effects of an MPP lasting 8 weeks. PMID:23663679

  13. Effectiveness of a Multimodal Therapy for Patients with Chronic Low Back Pain Regarding Pre-Admission Healthcare Utilization

    PubMed Central

    Borys, Constanze; Lutz, Johannes; Strauss, Bernhard; Altmann, Uwe

    2015-01-01

    Objective The aim of the study was to examine the effectiveness of an intensive inpatient three-week multimodal therapy. We focused especially on the impact on the multimodal therapy outcome of the pre-admission number of treatment types patients had received and of medical specialist groups patients had consulted. Methods 155 patients with chronic low back pain and indication for multimodal therapy were evaluated with respect to pain intensity, depression, anxiety, well-being, and pre-admission health care utilization. In our controlled clinical trial we compared N = 66 patients on the waiting list with N = 89 patients who received immediate treatment. The waiting list patients likewise attended multimodal therapy after the waiting period. Longitudinal post-treatment data for both were collected at three- and twelve-month follow-ups. The impact of pre-admission health care utilization on multimodal therapy outcome (post) was analysed by structural equation model. Results Compared to the control group, multimodal therapy patients’ pain intensity and psychological variables were significantly reduced. Longitudinal effects with respect to pre-measures were significant at three-month follow-up for pain intensity (ES = -0.48), well-being (ES = 0.78), anxiety (ES = -0.33), and depression (ES = -0.30). Effect sizes at twelve-month follow-up were small for anxiety (ES = -0.22), and moderate for general well-being (ES = 0.61). Structural equation model revealed that a higher number of pre-admission treatment types was associated with poorer post-treatment outcomes in pain intensity, well-being, and depression. Conclusion Multimodal therapy proved to be effective with regard to improvements in pain intensity, depression, anxiety, and well-being. The association between treatment effect and number of pre-admission pain treatment types suggests that patients would benefit more from attending multimodal therapy in an earlier stage of health care. PMID:26599232

  14. Multimodal management of dental pain with focus on alternative medicine: A novel herbal dental gel.

    PubMed

    Kumarswamy, A

    2016-01-01

    Dental pain is the most common symptom associated with a wide array of dental problems and significantly impacts the oral health-related quality of life. The epidemiology and prevalence of oral diseases that could lead to dental pain are diverse and indicate regional variations. Several researchers have dwelled into the neurobiology and pathophysiology of dental pain making the pain pathways more clear and deciphering the precise targets for the management of pain. Although a number of pharmacological drugs are available in the market, a significant percentage of the population in India prefers alternative herbal medication for relief from dental pain due to the side effects and interactions of pharmacological treatment. However, there is a void in dental literature pertaining to the use, benefits, and safety of the herbal medicines. Therefore, the present assessment has been penned down, focusing on the current multimodal approaches for treating dental pain, the current unmet need, and the role of herbal medication in India for the management of dental pain, with a discussion on novel herbal dental gel. PMID:27307656

  15. Multimodal management of dental pain with focus on alternative medicine: A novel herbal dental gel

    PubMed Central

    Kumarswamy, A.

    2016-01-01

    Dental pain is the most common symptom associated with a wide array of dental problems and significantly impacts the oral health-related quality of life. The epidemiology and prevalence of oral diseases that could lead to dental pain are diverse and indicate regional variations. Several researchers have dwelled into the neurobiology and pathophysiology of dental pain making the pain pathways more clear and deciphering the precise targets for the management of pain. Although a number of pharmacological drugs are available in the market, a significant percentage of the population in India prefers alternative herbal medication for relief from dental pain due to the side effects and interactions of pharmacological treatment. However, there is a void in dental literature pertaining to the use, benefits, and safety of the herbal medicines. Therefore, the present assessment has been penned down, focusing on the current multimodal approaches for treating dental pain, the current unmet need, and the role of herbal medication in India for the management of dental pain, with a discussion on novel herbal dental gel. PMID:27307656

  16. Interventional and multimodal pain rehabilitation in a child with meralgia paresthetica.

    PubMed

    Franklin, Andrew D; Cierny, G Bennett; Luckett, Twila R

    2016-09-01

    Meralgia paresthetica is a chronic pain syndrome that is extremely rare in the pediatric population. It is manifested by hypesthesia or pain in the distribution of the lateral femoral cutaneous nerve (LFCN) and is typically caused by entrapment as the nerve passes deep to the inguinal ligament. This sensory mononeuropathy is rare in children and diagnosis is typically delayed, often leading to prolonged functional impairment and unnecessary medical testing. A 9-year-old girl presented to the pain clinic with a 6-week history of right anterolateral thigh pain first noticed after a nontraumatic cheerleading practice. Comprehensive laboratory and radiographic evaluation by multiple prior specialists revealed no clear nociceptive source of pain. History and examination were consistent with a diagnosis of idiopathic, compressive meralgia paresthetica. Conservative management including physical therapy was followed for 2 weeks with only mild improvement noted. To facilitate physical therapy, an ultrasound-guided LFCN block was performed which confirmed the diagnosis by providing complete analgesia. The patient reported overall 25% improvement from multimodal therapy at another 2 weeks. A second LFCN block was performed with complete resolution of symptoms and restoration of function. The patient remains pain-free and has returned to walking, running, and competitive sports. The primary goal of pediatric chronic pain management, regardless of pain etiology, is early restoration of function to avoid prolonged absence from school, sports, or other productive activities and limit the psychological burden of chronic disease. PMID:27555210

  17. Pain hypervigilance is associated with greater clinical pain severity and enhanced experimental pain sensitivity among adults with symptomatic knee osteoarthritis

    PubMed Central

    Herbert, Matthew S.; Goodin, Burel R.; Pero, Samuel T.; Schmidt, Jessica K.; Sotolongo, Adriana; Bulls, Hailey W.; Glover, Toni L.; King, Christopher D.; Sibille, Kimberly T.; Cruz-Almeida, Yenisel; Staud, Roland; Fessler, Barri J.; Bradley, Laurence A.; Fillingim, Roger B.

    2014-01-01

    Background Pain hypervigilance is an important aspect of the fear-avoidance model of pain that may help explain individual differences in pain sensitivity among persons with knee osteoarthritis (OA). Purpose The purpose of this study was to examine the contribution of pain hypervigilance to clinical pain severity and experimental pain sensitivity in persons with symptomatic knee OA. Methods We analyzed cross-sectional data from 168 adults with symptomatic knee OA. Quantitative sensory testing was used to measure sensitivity to heat pain, pressure pain, and cold pain, as well as temporal summation of heat pain, a marker of central sensitization. Results Pain hypervigilance was associated with greater clinical pain severity, as well as greater pressure pain. Pain hypervigilance was also a significant predictor of temporal summation of heat pain. Conclusions Pain hypervigilance may be an important contributor to pain reports and experimental pain sensitivity among persons with knee OA. PMID:24352850

  18. A human experimental model of episodic pain.

    PubMed

    Petrini, Laura; Hennings, Kristian; Li, Xi; Negro, Francesco; Arendt-Nielsen, Lars

    2014-12-01

    An experimental model of daily episodic pain was developed to investigate peripheral sensitization and cortical reorganization in healthy individuals. Two experiments (A and B) were conducted. Experiments A and B consisted of one and five consecutive days, respectively, in which the participants were subjected to 45 min of intense painful cutaneous electrical stimulation (episodic pain session), using a stimulus paradigm that in animals has been shown to induce long-term potentiation. These electrical stimulations produced a verbal pain rating of approximately 85 on a 0-100 verbal rating scale (VRS). Physiological (blood flow and axon flare reflex), psychophysical (perception threshold and verbal pain ratings) and electrophysiological (128 channels recorded somatosensory evoked potential (SEP)) measurements were recorded. The stimulation evoked a visible axon flare reflex and caused significantly increased cutaneous blood flow around the site of the stimulation. Axon flare reflex and blood flow reached a plateau on day one in all the subjects and no significant changes between the days were observed. The results showed that the effect of the electrical stimulations changed over the five days; pain potentiation was induced on the first day (significant increase in the verbal pain ratings during the 45 min stimulation) but not on any of the subsequent days. After five days of subsequent pain induction, the global field power showed a significant reduction in P2 amplitude in the late stage (200-370 ms, in the central-parietal area). In conclusion, the results suggest that in healthy individuals this model of episodic pain produces a rapid adaptation after day one and that generates significant SEP changes at day five.

  19. Pain and Interoception Imaging Network (PAIN): A multimodal, multisite, brain-imaging repository for chronic somatic and visceral pain disorders.

    PubMed

    Labus, Jennifer S; Naliboff, Bruce; Kilpatrick, Lisa; Liu, Cathy; Ashe-McNalley, Cody; dos Santos, Ivani R; Alaverdyan, Mher; Woodworth, Davis; Gupta, Arpana; Ellingson, Benjamin M; Tillisch, Kirsten; Mayer, Emeran A

    2016-01-01

    The Pain and Interoception Imaging Network (PAIN) repository (painrepository.org) is a newly created NIH (NIDA/NCCAM) funded neuroimaging data repository that aims to accelerate scientific discovery regarding brain mechanisms in pain and to provide more rapid benefits to pain patients through the harmonization of efforts and data sharing. The PAIN Repository consists of two components, an Archived Repository and a Standardized Repository. Similar to other 'open' imaging repositories, neuroimaging researchers can deposit any dataset of chronic pain patients and healthy controls into the Archived Repository. Scans in the Archived Repository can be very diverse in terms of scanning procedures and clinical metadata, complicating the merging of datasets for analyses. The Standardized Repository overcomes these limitations through the use of standardized scanning protocols along with a standardized set of clinical metadata, allowing an unprecedented ability to perform pooled analyses. The Archived Repository currently includes 741 scans and is rapidly growing. The Standardized Repository currently includes 433 scans. Pain conditions currently represented in the PAIN repository include: irritable bowel syndrome, vulvodynia, migraine, chronic back pain, and inflammatory bowel disease. Both the PAIN Archived and Standardized Repositories promise to be important resources in the field of chronic pain research. The enhanced ability of the Standardized Repository to combine imaging, clinical and other biological datasets from multiple sites in particular make it a unique resource for significant scientific discoveries. PMID:25902408

  20. Assessing experimental visceral pain in dairy cattle: A pilot, prospective, blinded, randomized, and controlled study focusing on spinal pain proteomics.

    PubMed

    Rialland, P; Otis, C; de Courval, M-L; Mulon, P-Y; Harvey, D; Bichot, S; Gauvin, D; Livingston, A; Beaudry, F; Hélie, P; Frank, D; Del Castillo, J R E; Troncy, E

    2014-01-01

    Few studies have verified the validity of behavioral and physiological methods of pain assessment in cattle. This prospective, blinded, randomized controlled experimental study aimed to validate different methods of pain assessment during acute and chronic (up to 21 d postintervention) conditions in dairy cattle, in response to 3 analgesic treatments for traumatic reticuloperitonitis. Cerebrospinal fluid (CSF) biomarkers and mechanical sensitization were measured as indicators of centralized pain. Proteomics in the CSF were examined to detect specific (to pain intensity) and sensitive (responsive to analgesia) markers. Recordings of spontaneous behavior with video analysis, telemetered motor activity, pain scales, electrodermal activity, and plasma cortisol concentration were quantified at regular intervals. Cows were assigned to group 1 (n=4, standard control receiving aspirin), group 2 (n=5, test group receiving preemptive tolfenamic acid), or group 3 (n=3, positive control receiving preemptive multimodal analgesia composed of epidural morphine, plus tolfenamic acid and butorphanol). Rescue analgesia was administered as needed. Generalized estimating equations tested group differences and the influence of rescue analgesia on the measurements. All 3 groups demonstrated a long-term decrease in a CSF protein identified as transthyretin. The decrease in transthyretin expression inversely correlated with the expected level of analgesia (group 1<2<3). Moreover, in group 1, CSF noradrenaline decreased long term, cows were hypersensitive to mechanical stimulation, and they demonstrated signs of discomfort with higher motor activity and "agitation while lying" recorded from video analysis. Decreased "feeding behavior," observer-reported pain scales, electrodermal activity, and plasma cortisol concentration were inconsistent to differentiate pain intensity between groups. In summary, changes in CSF biomarkers and mechanical sensitization reflected modulation of central

  1. Heritability of pain catastrophizing and associations with experimental pain outcomes: a twin study.

    PubMed

    Trost, Zina; Strachan, Eric; Sullivan, Michael; Vervoort, Tine; Avery, Ally R; Afari, Niloofar

    2015-03-01

    This study used a twin paradigm to examine genetic and environmental contributions to pain catastrophizing and the observed association between pain catastrophizing and cold-pressor task (CPT) outcomes. Male and female monozygotic (n = 206) and dizygotic twins (n = 194) from the University of Washington Twin Registry completed a measure of pain catastrophizing and performed a CPT challenge. As expected, pain catastrophizing emerged as a significant predictor of several CPT outcomes, including cold-pressor Immersion Tolerance, Pain Tolerance, and Delayed Pain Rating. The heritability estimate for pain catastrophizing was found to be 37% with the remaining 63% of variance attributable to unique environmental influence. Additionally, the observed associations between pain catastrophizing and CPT outcomes were not found attributable to shared genetics or environmental exposure, which suggests a direct relationship between catastrophizing and experimental pain outcomes. This study is the first to examine the heritability of pain catastrophizing and potential processes by which pain catastrophizing is related to experimental pain response. PMID:25599234

  2. Heritability of pain catastrophizing and associations with experimental pain outcomes: a twin study.

    PubMed

    Trost, Zina; Strachan, Eric; Sullivan, Michael; Vervoort, Tine; Avery, Ally R; Afari, Niloofar

    2015-03-01

    This study used a twin paradigm to examine genetic and environmental contributions to pain catastrophizing and the observed association between pain catastrophizing and cold-pressor task (CPT) outcomes. Male and female monozygotic (n = 206) and dizygotic twins (n = 194) from the University of Washington Twin Registry completed a measure of pain catastrophizing and performed a CPT challenge. As expected, pain catastrophizing emerged as a significant predictor of several CPT outcomes, including cold-pressor Immersion Tolerance, Pain Tolerance, and Delayed Pain Rating. The heritability estimate for pain catastrophizing was found to be 37% with the remaining 63% of variance attributable to unique environmental influence. Additionally, the observed associations between pain catastrophizing and CPT outcomes were not found attributable to shared genetics or environmental exposure, which suggests a direct relationship between catastrophizing and experimental pain outcomes. This study is the first to examine the heritability of pain catastrophizing and potential processes by which pain catastrophizing is related to experimental pain response.

  3. Effects of the Web Behavior Change Program for Activity and Multimodal Pain Rehabilitation: Randomized Controlled Trial

    PubMed Central

    Michaelson, Peter; Gard, Gunvor; Eriksson, Margareta K

    2016-01-01

    Background Web-based interventions with a focus on behavior change have been used for pain management, but studies of Web-based interventions integrated in clinical practice are lacking. To emphasize the development of cognitive skills and behavior, and to increase activity and self-care in rehabilitation, the Web Behavior Change Program for Activity (Web-BCPA) was developed and added to multimodal pain rehabilitation (MMR). Objective The objective of our study was to evaluate the effects of MMR in combination with the Web-BCPA compared with MMR among persons with persistent musculoskeletal pain in primary health care on pain intensity, self-efficacy, and copying, as part of a larger collection of data. Web-BCPA adherence and feasibility, as well as treatment satisfaction, were also investigated. Methods A total of 109 participants, mean age 43 (SD 11) years, with persistent pain in the back, neck, shoulder, and/or generalized pain were recruited to a randomized controlled trial with two intervention arms: (1) MMR+WEB (n=60) and (2) MMR (n=49). Participants in the MMR+WEB group self-guided through the eight modules of the Web-BCPA: pain, activity, behavior, stress and thoughts, sleep and negative thoughts, communication and self-esteem, solutions, and maintenance and progress. Data were collected with a questionnaire at baseline and at 4 and 12 months. Outcome measures were pain intensity (Visual Analog Scale), self-efficacy to control pain and to control other symptoms (Arthritis Self-Efficacy Scale), general self-efficacy (General Self-Efficacy Scale), and coping (two-item Coping Strategies Questionnaire; CSQ). Web-BCPA adherence was measured as minutes spent in the program. Satisfaction and Web-BCPA feasibility were assessed by a set of items. Results Of 109 participants, 99 received the allocated intervention (MMR+WEB: n=55; MMR: n=44); 88 of 99 (82%) completed the baseline and follow-up questionnaires. Intention-to-treat analyses were performed with a sample

  4. Multimodal Chiropractic Care of Pain and Disability for a Patient Diagnosed With Benign Joint Hypermobility Syndrome: A Case Report

    PubMed Central

    Strunk, Richard G.; Pfefer, Mark T.; Dube, Derrick

    2014-01-01

    Objective The purpose of this case report is to describe multimodal chiropractic care of a female patient diagnosed with benign joint hypermobility syndrome (BJHS) and a history of chronic spine pain. Clinical features A 23-year-old white female presented for chiropractic care with chronic low back pain, neck pain, and headaches. The patient was diagnosed with BJHS, including joint hypermobility of her thumbs, elbows, right knee, and lumbopelvic region. A 6-year history of low back pain and varicose veins in her posterior thighs and knees were additional significant diagnostic findings of BJHS. Interventions and outcomes The treatment consisted of spinal and extremity manipulation, Graston technique, and postisometric relaxation combined with sensory motor stimulation and scapular stabilization exercises. The patient was seen 15 times over an 18-week period. After 18 weeks of care, the Revised Oswestry Low Back Questionnaire and Headache Disability Index demonstrated clinically important improvements with her low back pain and headache; but little change was noted in her neck pain as measured by the Neck Disability Index. Conclusion This patient with BJHS who had decreased disability and spine pain improved after a course of multimodal chiropractic care. PMID:24711783

  5. Prospective medium-term results of multimodal pain management in patients with lumbar radiculopathy

    PubMed Central

    Benditz, A.; Madl, M.; Loher, M.; Grifka, J.; Boluki, D.; Linhardt, O.

    2016-01-01

    Lumbar radiculopathy is one of the most common diseases of modern civilisation. Multimodal pain management (MPM) represents a central approach to avoiding surgery. Only few medium-term results have been published in the literature so far. This study compared subjective and objective as well as anamnestic and clinical parameters of 60 patients who had undergone inpatient MPM because of lumbar radiculopathy before and 1 year ±2 weeks after treatment. The majority of patients were very satisfied (35%) or satisfied (52%) with the treatment outcome. Merely 8 patients commented neutrally and none negatively. The finger-floor distance had decreased significantly (p < 0.01), and 30 patients (50%) had shown improved mobility of the spine after therapy. The need for painkillers had also been significantly reduced after 1 year. The arithmetical average of pain on a visual analogue scale was 7.21 before treatment, which had significantly decreased to 3.58 at follow-up (p < 0.01). MPM is an effective approach for treating lumbar radiculopathy by mechanical nerve root irritation. Therefore, in the absence of an absolute indication for surgery or an absolute contradiction for MPM, patients should first be treated with this minimally invasive therapy. PMID:27305956

  6. Patient-Controlled Epidural Analgesia or Multimodal Pain Regimen with Periarticular Injection After Total Hip Arthroplasty

    PubMed Central

    Jules-Elysee, Kethy M.; Goon, Amanda K.; Westrich, Geoffrey H.; Padgett, Douglas E.; Mayman, David J.; Ranawat, Amar S.; Ranawat, Chitranjan S.; Lin, Yi; Kahn, Richard L.; Bhagat, Devan D.; Goytizolo, Enrique A.; Ma, Yan; Reid, Shane C.; Curren, Jodie; YaDeau, Jacques T.

    2015-01-01

    Background: The optimal postoperative analgesia after primary total hip arthroplasty remains in question. This randomized, double-blind, placebo-controlled study compared the use of patient-controlled epidural analgesia (PCEA) with use of a multimodal pain regimen including periarticular injection (PAI). We hypothesized that PAI would lead to earlier readiness for discharge, decreased opioid consumption, and lower pain scores. Methods: Forty-one patients received PAI, and forty-three patients received PCEA. Preoperatively, both groups were administered dexamethasone (6 mg, orally). The PAI group received a clonidine patch and sustained-release oxycodone (10 mg), while the PCEA group had placebo. Both groups received combined spinal-epidural anesthesia and used an epidural pain pump postoperatively; the PAI group had normal saline solution, while the PCEA group had bupivacaine and hydromorphone. The primary outcome, readiness for discharge, required the discontinuation of the epidural, a pain score of <4 (numeric rating scale) without parenteral narcotics, normal eating, minimal nausea, urination without a catheter, a dry surgical wound, no acute medical problems, and the ability to independently transfer and walk 12.2 m (40 ft). Results: The mean time to readiness for discharge (and standard deviation) was 2.4 ± 0.7 days (PAI) compared with 2.3 ± 0.8 days (PCEA) (p = 0.86). The mean length of stay was 3.0 ± 0.8 days (PAI) compared with 3.1 ± 0.7 days (PCEA) (p = 0.46). A significant mean difference in pain score of 0.74 with ambulation (p = 0.01; 95% confidence interval [CI], 0.18 to 1.31) and 0.80 during physical therapy (p = 0.03; 95% CI, 0.09 to 1.51) favored the PCEA group. The mean opioid consumption (oral morphine equivalents in milligrams) was significantly higher in the PAI group on postoperative day 0 (43 ± 21 compared with 28 ± 23; p = 0.002) and postoperative days 0 through 2 (136 ± 59 compared with 90 ± 79; p = 0.004). Opioid-Related Symptom

  7. Spontaneous Chronic Pain After Experimental Thoracotomy Revealed by Conditioned Place Preference: Morphine Differentiates Tactile Evoked Pain From Spontaneous Pain.

    PubMed

    Hung, Ching-Hsia; Wang, Jeffrey Chi-Fei; Strichartz, Gary R

    2015-09-01

    Chronic pain after surgery limits social activity, interferes with work, and causes emotional suffering. A major component of such pain is reported as resting or spontaneous pain with no apparent external stimulus. Although experimental animal models can simulate the stimulus-evoked chronic pain that occurs after surgery, there have been no studies of spontaneous chronic pain in such models. Here the conditioned place preference (CPP) paradigm was used to reveal resting pain after experimental thoracotomy. Male Sprague Dawley rats received a thoracotomy with 1-hour rib retraction, resulting in evoked tactile hypersensitivity, previously shown to last for at least 9 weeks. Intraperitoneal injections of morphine (2.5 mg/kg) or gabapentin (40 mg/kg) gave equivalent 2- to 3-hour-long relief of tactile hypersensitivity when tested 12 to 14 days postoperatively. In separate experiments, single trial CPP was conducted 1 week before thoracotomy and then 12 days (gabapentin) or 14 days (morphine) after surgery, followed the next day by 1 conditioning session with morphine or gabapentin, both versus saline. The gabapentin-conditioned but not the morphine-conditioned rats showed a significant preference for the analgesia-paired chamber, despite the equivalent effect of the 2 agents in relieving tactile allodynia. These results show that experimental thoracotomy in rats causes spontaneous pain and that some analgesics, such as morphine, that reduce evoked pain do not also relieve resting pain, suggesting that pathophysiological mechanisms differ between these 2 aspects of long-term postoperative pain. Perspective: Spontaneous pain, a hallmark of chronic postoperative pain, is demonstrated here in a rat model of experimental postthoracotomy pain, further validating the use of this model for the development of analgesics to treat such symptoms. Although stimulus-evoked pain was sensitive to systemic morphine, spontaneous pain was not, suggesting different mechanistic

  8. Spontaneous Chronic Pain After Experimental Thoracotomy Revealed by Conditioned Place Preference: Morphine Differentiates Tactile Evoked Pain From Spontaneous Pain.

    PubMed

    Hung, Ching-Hsia; Wang, Jeffrey Chi-Fei; Strichartz, Gary R

    2015-09-01

    Chronic pain after surgery limits social activity, interferes with work, and causes emotional suffering. A major component of such pain is reported as resting or spontaneous pain with no apparent external stimulus. Although experimental animal models can simulate the stimulus-evoked chronic pain that occurs after surgery, there have been no studies of spontaneous chronic pain in such models. Here the conditioned place preference (CPP) paradigm was used to reveal resting pain after experimental thoracotomy. Male Sprague Dawley rats received a thoracotomy with 1-hour rib retraction, resulting in evoked tactile hypersensitivity, previously shown to last for at least 9 weeks. Intraperitoneal injections of morphine (2.5 mg/kg) or gabapentin (40 mg/kg) gave equivalent 2- to 3-hour-long relief of tactile hypersensitivity when tested 12 to 14 days postoperatively. In separate experiments, single trial CPP was conducted 1 week before thoracotomy and then 12 days (gabapentin) or 14 days (morphine) after surgery, followed the next day by 1 conditioning session with morphine or gabapentin, both versus saline. The gabapentin-conditioned but not the morphine-conditioned rats showed a significant preference for the analgesia-paired chamber, despite the equivalent effect of the 2 agents in relieving tactile allodynia. These results show that experimental thoracotomy in rats causes spontaneous pain and that some analgesics, such as morphine, that reduce evoked pain do not also relieve resting pain, suggesting that pathophysiological mechanisms differ between these 2 aspects of long-term postoperative pain. Perspective: Spontaneous pain, a hallmark of chronic postoperative pain, is demonstrated here in a rat model of experimental postthoracotomy pain, further validating the use of this model for the development of analgesics to treat such symptoms. Although stimulus-evoked pain was sensitive to systemic morphine, spontaneous pain was not, suggesting different mechanistic

  9. Experimental Pain Responses Support Peripheral and Central Sensitization in Patients with Unilateral Shoulder Pain

    PubMed Central

    Coronado, Rogelio A.; Simon, Corey B.; Valencia, Carolina; George, Steven Z.

    2013-01-01

    Objective The aims of this study were to 1) examine the pattern of experimental pain responses in the affected and non-affected extremities in patients with shoulder pain and 2) explore the intra-individual association between sensitization states derived from experimental pain testing. Methods Experimental pain responses from 58 patients with shoulder pain (17 females, ages 18 to 52) were compared to those from 56 age- and sex-matched healthy volunteers (16 females, ages 21 to 58). Experimental pain responses included pressure pain threshold (PPT), thermal pain threshold and tolerance, and suprathreshold heat pain response (SHPR). Comparisons were made between the affected and non-affected extremity of clinical participants and the average response of extremities in healthy participants. Peripheral and central sensitization indexes were computed for clinical participants using standardized scores and percentile cut-offs based on the data from the healthy control sample. Experimental pain responses in clinical participants observed beyond the 25th and 75th percentile of healthy control sample responses were used for investigation of intra-individual association of sensitization states. Results PPT on the affected side acromion and masseter of clinical participants were diminished compared to their non-affected side (p < 0.015). Bilateral sensitivity in clinical participants was noted for PPT at the acromion and SHPR (p < 0.015). Peripheral and central sensitization indexes demonstrated that individuals with shoulder pain present with variable patterns of peripheral and central sensitization. Conclusions Collectively, experimental pain responses supported peripheral and central sensitization in response to pressure and thermal stimuli. No clear association was made between individuals exhibiting peripheral or central sensitization and suggests heterogeneity in pain processing in this clinical population. PMID:23619203

  10. An Innovative and Portable Multimodal Pain Relief Device for the Management of Neuropathic Low Back Pain - a Study from Kashmir (Southeast Asia)

    PubMed Central

    Lone, Baseer-ul-Rasool; Beigh, Mirza-Idrees-ul-Haq; Manzoor, Mushbiq

    2016-01-01

    We developed a portable multimodal system with seven different mechanisms of pain relief incorporated into a lumbar belt called the Comfort-N-Harmony Belt (C&H belt). Here, we describe the technical details of the system and also summarize the effects of this multimodal pain relieving technology as an adjuvant to analgesics versus analgesics alone, on the level of pain, improvement of psychological status, disability, and the quality of life in the patients with neuropathic low back pain (LBP). We tracked the volunteers who were following up at a tertiary health care center for the complaints of neuropathic LBP of minimum three months duration and were on analgesics alone with no relief in the severity of the pain. Study group A (n = 45) consisted of volunteers with LBP on C&H belt therapy, along with the usually prescribed analgesic intake, and group B (n = 45) with LBP volunteers on analgesics, plus a similar looking but plain leather belt (placebo). For pain, the VAS (Visual Analogue Scale); for anxiety and depression, the (HADS) Hospital Anxiety-Depression Scale; for disability, the RMDQ (Roland Morris Disability Questionnaire); and for quality of life, (NHP) Nottingham-Health-Profile were used before and after the study period.  There were no significant differences in demographic variables between the groups (p < 0.05). After the study period of one month, VAS, RMDQ, NHP-pain, NHP-physical activity, and HADS scores in both groups were significantly improved compared to the pre-treatment scores (p < 0.05). Group A also showed significant improvements in the scores of NHP-energy level and NHP-social isolation (p < 0.05). The post-treatment scores did not significantly show any difference between the two groups (p > 0.05). However, in comparison of pre- and post-treatment scores, the pre-treatment score values of RMDQ, NHP-pain, NHP-physical activity, and NHP-social isolation were much higher in group A compared to the group B, but still these scores were

  11. An Innovative and Portable Multimodal Pain Relief Device for the Management of Neuropathic Low Back Pain - a Study from Kashmir (Southeast Asia).

    PubMed

    Tarfarosh, Shah Faisal Ahmad; Lone, Baseer-Ul-Rasool; Beigh, Mirza-Idrees-Ul-Haq; Manzoor, Mushbiq

    2016-01-01

    We developed a portable multimodal system with seven different mechanisms of pain relief incorporated into a lumbar belt called the Comfort-N-Harmony Belt (C&H belt). Here, we describe the technical details of the system and also summarize the effects of this multimodal pain relieving technology as an adjuvant to analgesics versus analgesics alone, on the level of pain, improvement of psychological status, disability, and the quality of life in the patients with neuropathic low back pain (LBP). We tracked the volunteers who were following up at a tertiary health care center for the complaints of neuropathic LBP of minimum three months duration and were on analgesics alone with no relief in the severity of the pain. Study group A (n = 45) consisted of volunteers with LBP on C&H belt therapy, along with the usually prescribed analgesic intake, and group B (n = 45) with LBP volunteers on analgesics, plus a similar looking but plain leather belt (placebo). For pain, the VAS (Visual Analogue Scale); for anxiety and depression, the (HADS) Hospital Anxiety-Depression Scale; for disability, the RMDQ (Roland Morris Disability Questionnaire); and for quality of life, (NHP) Nottingham-Health-Profile were used before and after the study period.  There were no significant differences in demographic variables between the groups (p < 0.05). After the study period of one month, VAS, RMDQ, NHP-pain, NHP-physical activity, and HADS scores in both groups were significantly improved compared to the pre-treatment scores (p < 0.05). Group A also showed significant improvements in the scores of NHP-energy level and NHP-social isolation (p < 0.05). The post-treatment scores did not significantly show any difference between the two groups (p > 0.05). However, in comparison of pre- and post-treatment scores, the pre-treatment score values of RMDQ, NHP-pain, NHP-physical activity, and NHP-social isolation were much higher in group A compared to the group B, but still these scores were

  12. An Innovative and Portable Multimodal Pain Relief Device for the Management of Neuropathic Low Back Pain - a Study from Kashmir (Southeast Asia)

    PubMed Central

    Lone, Baseer-ul-Rasool; Beigh, Mirza-Idrees-ul-Haq; Manzoor, Mushbiq

    2016-01-01

    We developed a portable multimodal system with seven different mechanisms of pain relief incorporated into a lumbar belt called the Comfort-N-Harmony Belt (C&H belt). Here, we describe the technical details of the system and also summarize the effects of this multimodal pain relieving technology as an adjuvant to analgesics versus analgesics alone, on the level of pain, improvement of psychological status, disability, and the quality of life in the patients with neuropathic low back pain (LBP). We tracked the volunteers who were following up at a tertiary health care center for the complaints of neuropathic LBP of minimum three months duration and were on analgesics alone with no relief in the severity of the pain. Study group A (n = 45) consisted of volunteers with LBP on C&H belt therapy, along with the usually prescribed analgesic intake, and group B (n = 45) with LBP volunteers on analgesics, plus a similar looking but plain leather belt (placebo). For pain, the VAS (Visual Analogue Scale); for anxiety and depression, the (HADS) Hospital Anxiety-Depression Scale; for disability, the RMDQ (Roland Morris Disability Questionnaire); and for quality of life, (NHP) Nottingham-Health-Profile were used before and after the study period.  There were no significant differences in demographic variables between the groups (p < 0.05). After the study period of one month, VAS, RMDQ, NHP-pain, NHP-physical activity, and HADS scores in both groups were significantly improved compared to the pre-treatment scores (p < 0.05). Group A also showed significant improvements in the scores of NHP-energy level and NHP-social isolation (p < 0.05). The post-treatment scores did not significantly show any difference between the two groups (p > 0.05). However, in comparison of pre- and post-treatment scores, the pre-treatment score values of RMDQ, NHP-pain, NHP-physical activity, and NHP-social isolation were much higher in group A compared to the group B, but still these scores were

  13. Heritability of Pain Catastrophizing and Associations with Experimental Pain Outcomes: A Twin Study

    PubMed Central

    Trost, Zina; Strachan, Eric; Sullivan, Michael; Vervoort, Tine; Avery, Ally R.; Afari, Niloofar

    2014-01-01

    The current study employed a twin paradigm to examine the genetic and environmental contributions to pain catastrophizing as well as the observed association between pain catastrophizing and cold pressor task (CPT) outcomes. Male and female monozygotic (n=206) and dizygotic twins (n=194) from the University of Washington Twin Registry completed a measure of pain catastrophizing and performed a CPT challenge. As expected, pain catastrophizing emerged as a significant predictor of several CPT outcomes, including cold pressor immersion tolerance, pain tolerance, and delayed pain rating. The heritability estimate for pain catastrophizing was found to be 37% with the remaining 63% of variance attributable to unique environmental influence. Additionally, the observed associations between pain catastrophizing and CPT outcomes were not found attributable to shared genetics or environmental exposure, suggesting a direct relationship between catastrophizing and experimental pain outcomes. This study is the first to examine the heritability of pain catastrophizing and potential processes by which pain catastrophizing is related to experimental pain response. PMID:25599234

  14. The influence of experimentally induced pain on shoulder muscle activity.

    PubMed

    Diederichsen, Louise Pyndt; Winther, Annika; Dyhre-Poulsen, Poul; Krogsgaard, Michael R; Nørregaard, Jesper

    2009-04-01

    Muscle function is altered in painful shoulder conditions. However, the influence of shoulder pain on muscle coordination of the shoulder has not been fully clarified. The aim of the present study was to examine the effect of experimentally induced shoulder pain on shoulder muscle function. Eleven healthy men (range 22-27 years), with no history of shoulder or cervical problems, were included in the study. Pain was induced by 5% hypertonic saline injections into the supraspinatus muscle or subacromially. Seated in a shoulder machine, subjects performed standardized concentric abduction (0 degrees -105 degrees) at a speed of approximately 120 degrees/s, controlled by a metronome. During abduction, electromyographic (EMG) activity was recorded by intramuscular wire electrodes inserted in two deeply located shoulder muscles and by surface-electrodes over six superficially located shoulder muscles. EMG was recorded before pain, during pain and after pain had subsided and pain intensity was continuously scored on a visual analog scale (VAS). During abduction, experimentally induced pain in the supraspinatus muscle caused a significant decrease in activity of the anterior deltoid, upper trapezius and the infraspinatus and an increase in activity of lower trapezius and latissimus dorsi muscles. Following subacromial injection a significantly increased muscle activity was seen in the lower trapezius, the serratus anterior and the latissimus dorsi muscles. In conclusion, this study shows that acute pain both subacromially and in the supraspinatus muscle modulates coordination of the shoulder muscles during voluntary movements. During painful conditions, an increased activity was detected in the antagonist (latissimus), which support the idea that localized pain affects muscle activation in a way that protects the painful structure. Further, the changes in muscle activity following subacromial pain induction tend to expand the subacromial space and thereby decrease the load

  15. Pain referral and regional deep tissue hyperalgesia in experimental human hip pain models.

    PubMed

    Izumi, Masashi; Petersen, Kristian Kjær; Arendt-Nielsen, Lars; Graven-Nielsen, Thomas

    2014-04-01

    Hip disorder patients typically present with extensive pain referral and hyperalgesia. To better understand underlying mechanisms, an experimental hip pain model was established in which pain referrals and hyperalgesia could be studied under standardized conditions. In 16 healthy subjects, pain was induced by hypertonic saline injection into the gluteus medius tendon (GMT), adductor longus tendon (ALT), or gluteus medius muscle (GMM). Isotonic saline was injected contralaterally as control. Pain intensity was assessed on a visual analogue scale (VAS), and subjects mapped the pain distribution. Before, during, and after injections, passive hip joint pain provocation tests were completed, together with quantitative sensory testing as follows: pressure pain thresholds (PPTs), cuff algometry pain thresholds (cuff PPTs), cutaneous pin-prick sensitivity, and thermal pain thresholds. Hypertonic saline injected into the GMT resulted in higher VAS scores than hypertonic injections into the ALT and GMM (P<.05). Referred pain areas spread to larger parts of the leg after GMT and GMM injections compared with more regionalized pain pattern after ALT injections (P<.05). PPTs at the injection site were decreased after hypertonic saline injections into GMT and GMM compared with baseline, ALT injections, and isotonic saline. Cuff PPTs from the thigh were decreased after hypertonic saline injections into the ALT compared with baseline, GMT injections, and isotonic saline (P<.05). More subjects had positive joint pain provocation tests after hypertonic compared with isotonic saline injections (P<.05), indicating that this provocation test also assessed hyperalgesia in extra-articular soft tissues. The experimental models may open for better understanding of pain mechanisms associated with painful hip disorders.

  16. Fuel optimal control of an experimental multi-mode system

    NASA Technical Reports Server (NTRS)

    Redmond, J.; Mayer, J. L.; Silverberg, L.

    1992-01-01

    In this paper, the dynamic characteristics associated with the fuel optimal control of a harmonic oscillator are utilized in the development of a near fuel optimal feedback control strategy for spacecraft vibration suppression. In this scheme, single level thrust actuators are governed by recursive computations of the standard deviations of displacement and velocity at the actuator's locations. The algorithm was tested on an experimental structure possessing a significant number of flexible body modes. The structure's response to both single and multiple mode excitation is presented.

  17. The genetic influences on oxycodone response characteristics in human experimental pain.

    PubMed

    Olesen, Anne E; Sato, Hiroe; Nielsen, Lecia M; Staahl, Camilla; Droney, Joanne; Gretton, Sophy; Branford, Ruth; Drewes, Asbjørn M; Arendt-Nielsen, Lars; Riley, Julia; Ross, Joy

    2015-08-01

    Human experimental pain studies are of value to study basic pain mechanisms under controlled conditions. The aim of this study was to investigate whether genetic variation across selected mu-, kappa- and delta-opioid receptor genes (OPRM1, OPRK1and OPRD1, respectively) influenced analgesic response to oxycodone in healthy volunteers. Experimental multimodal, multitissue pain data from previously published studies carried out in Caucasian volunteers were used. Data on thermal skin pain tolerance threshold (PTT) (n = 37), muscle pressure PTT (n = 31), mechanical visceral PTT (n = 43) and thermal visceral PTT (n = 41) were included. Genetic associations with pain outcomes were explored. Nineteen opioid receptor genetic polymorphisms were included in this study. Variability in oxycodone response to skin heat was associated with OPRM1 single-nucleotide polymorphisms (SNPs) rs589046 (P < 0.0001) and rs563649 (P < 0.0001). Variability in oxycodone response to visceral pressure was associated with four OPRM1 SNPs: rs589046 (P = 0.015), rs1799971 (P = 0.045), rs9479757 (P = 0.009) and rs533586 (P = 0.046). OPRM1 SNPs were not associated with oxycodone visceral heat threshold, however, one OPRD1 rs419335 reached significance (P = 0.015). Another OPRD1 SNP rs2234918 (P = 0.041) was associated with muscle pressure. There were no associations with OPRK1 SNPs and oxycodone response for any of the pain modalities. Associations were found between analgesic effects of oxycodone and OPRM1 and OPRD1 SNPs; therefore, variation in opioid receptor genes may partly explain responder characteristics to oxycodone.

  18. Experimental pelvic pain facilitates pain provocation tests and causes regional hyperalgesia.

    PubMed

    Palsson, Thorvaldur Skuli; Graven-Nielsen, Thomas

    2012-11-01

    The extra-articular sacroiliac joint (SIJ) structure is a potential source for low back and pelvic pain. This study hypothesised that experimental pain induced in a superficial pelvic ligament causes (1) hyperalgesia to pressure, (2) distinct pain referral, and (3) an increased frequency of positive pain provocation tests of the SIJ complex. Thirty healthy subjects (15 females) participated in this study designed as a randomised crossover trial. Pain was induced in the long posterior sacroiliac ligament by injection of hypertonic saline, with the contralateral ligament injected with isotonic saline as control. Pain intensity was assessed on an electronic visual analogue scale (VAS). Pressure pain thresholds (PPTs) and pain provocation tests were assessed on 3 occasions: at baseline, after injection, and when pain had subsided. PPT sites were located bilaterally at the injection site, lateral to spinous processes of S2 and L5, and at the gluteus medius and gastrocnemius muscles. Hypertonic saline caused significantly higher VAS scores and more extended pain referral than isotonic saline (P<0.001). PPTs at the injection site and lateral to S2 were significantly reduced after hypertonic saline compared with baseline and isotonic saline (P<0.002). Significantly more subjects had positive pain provocation tests after hypertonic (67% of subjects) compared with isotonic saline (20%; P<0.001). These data demonstrate that the extra-articular SIJ structure accommodates nociceptors that are capable of inducing pain referral and regional hyperalgesia sensitive to manual pain provocation tests similar to what previously have been found in pelvic girdle pain patients.

  19. The influence of experimental pain intensity in the local and referred pain area on somatosensory perception in the area of referred pain.

    PubMed

    Kosek, Eva; Hansson, Per

    2002-01-01

    The aim of this study was to investigate the influence of experimental pain intensity in the local and referred pain area on somatosensory perception thresholds in the area of referred pain. Pain was induced by intramuscular electrical stimulation of the left infraspinatus muscle in 12 healthy individuals. The stimulation corresponded to the local pain threshold ("mild local pain"), the referred pain threshold ("mild referred pain"), and a pain intensity corresponding to 2 on a 10-point category scale in the referred pain area ("moderate referred pain"). Quantitative sensory testing was performed to assess perception thresholds in the referred pain area and the homologous contralateral area before and during stimulation. Perception thresholds to light touch (LTTs), pressure pain (PPTs), and to innocuous as well as noxious warmth and cold were assessed. During stimulation the LTTs increased in the referred pain area compared to baseline, uninfluenced by pain intensity. Perception thresholds to innocuous cold and warmth increased bilaterally during the stimulation, without relation to pain intensity. Heat pain thresholds were not affected. Compared to baseline, PPTs increased bilaterally during stimulation corresponding to "mild local pain" and "mild referred pain", respectively, and a further increase was seen during "moderate referred pain". The decreased sensitivity to innocuous cold, warmth, and pressure pain was bilateral, indicating activation of endogenous net inhibitory mechanisms interacting bilaterally. We found no influence of pain intensity on somatosensory thresholds restricted to the referred pain area and light touch was the only affected modality in the referred pain area only.

  20. SPONTANEOUS CHRONIC PAIN AFTER EXPERIMENTAL THORACTOMY REVEALED BY CONDITIONED PLACE PREFERENCE: morphine differentiates tactile evoked pain from spontaneous pain

    PubMed Central

    Hung, Ching-Hsia; Wang, Jeffrey Chi-Fei; Strichartz, Gary

    2015-01-01

    Chronic pain following surgery limits social activity, interferes with work and causes emotional suffering. A major component of such pain is is reported as “resting” or spontaneous pain with no apparent external stimulus. Although experimental animal models can simulate the stimulus-evoked chronic pain that occurs after surgery, there have been no studies of spontaneous chronic pain in such models. Here the Conditioned Place Preference (CPP) paradigm was used to reveal resting pain after experimental thoracotomy. Male Sprague-Dawley rats received a thoracotomy with 1 hour rib retraction, resulting in evoked tactile hypersensitivity, previously shown to last for at least 9 weeks. Intraperitoneal injections of morphine (2.5 mg/kg) or gabapentin (40mg/kg) gave equivalent 2-3h long relief of tactile hypersensitivity, when tested 12-14 days post-operative. In separate experiments, single trial CPP was conducted 1 week before thoracotomy and then 12 days (gabapentin) or 14 days (morphine) after surgery, followed the next day by one conditioning sesssion with morphine or gabapentin, both vs saline. The gabapentin-conditioned, but not the morphine-conditioned rats showed a significant preference for the analgesia-paired chamber, despite the two agents’ equivalent effect in relieving tactile allodynia. These results show that experimental thoracotomy in rats causes spontaneous pain, and that some analgesics, such as morphine, that reduce evoked pain do not also relieve resting pain, suggesting that pathophysiological mechanisms differ between these two aspects of long-term post-operative pain. PMID:26116369

  1. A magnetoencephalography study of multi-modal processing of pain anticipation in primary sensory cortices.

    PubMed

    Gopalakrishnan, R; Burgess, R C; Plow, E B; Floden, D P; Machado, A G

    2015-09-24

    Pain anticipation plays a critical role in pain chronification and results in disability due to pain avoidance. It is important to understand how different sensory modalities (auditory, visual or tactile) may influence pain anticipation as different strategies could be applied to mitigate anticipatory phenomena and chronification. In this study, using a countdown paradigm, we evaluated with magnetoencephalography the neural networks associated with pain anticipation elicited by different sensory modalities in normal volunteers. When encountered with well-established cues that signaled pain, visual and somatosensory cortices engaged the pain neuromatrix areas early during the countdown process, whereas the auditory cortex displayed delayed processing. In addition, during pain anticipation, the visual cortex displayed independent processing capabilities after learning the contextual meaning of cues from associative and limbic areas. Interestingly, cross-modal activation was also evident and strong when visual and tactile cues signaled upcoming pain. Dorsolateral prefrontal cortex and mid-cingulate cortex showed significant activity during pain anticipation regardless of modality. Our results show pain anticipation is processed with great time efficiency by a highly specialized and hierarchical network. The highest degree of higher-order processing is modulated by context (pain) rather than content (modality) and rests within the associative limbic regions, corroborating their intrinsic role in chronification.

  2. A magnetoencephalography study of multi-modal processing of pain anticipation in primary sensory cortices.

    PubMed

    Gopalakrishnan, R; Burgess, R C; Plow, E B; Floden, D P; Machado, A G

    2015-09-24

    Pain anticipation plays a critical role in pain chronification and results in disability due to pain avoidance. It is important to understand how different sensory modalities (auditory, visual or tactile) may influence pain anticipation as different strategies could be applied to mitigate anticipatory phenomena and chronification. In this study, using a countdown paradigm, we evaluated with magnetoencephalography the neural networks associated with pain anticipation elicited by different sensory modalities in normal volunteers. When encountered with well-established cues that signaled pain, visual and somatosensory cortices engaged the pain neuromatrix areas early during the countdown process, whereas the auditory cortex displayed delayed processing. In addition, during pain anticipation, the visual cortex displayed independent processing capabilities after learning the contextual meaning of cues from associative and limbic areas. Interestingly, cross-modal activation was also evident and strong when visual and tactile cues signaled upcoming pain. Dorsolateral prefrontal cortex and mid-cingulate cortex showed significant activity during pain anticipation regardless of modality. Our results show pain anticipation is processed with great time efficiency by a highly specialized and hierarchical network. The highest degree of higher-order processing is modulated by context (pain) rather than content (modality) and rests within the associative limbic regions, corroborating their intrinsic role in chronification. PMID:26210576

  3. Mechanisms of acupuncture analgesia for clinical and experimental pain.

    PubMed

    Staud, Roland; Price, Donald D

    2006-05-01

    There is convincing evidence that acupuncture (AP) is effective for the treatment of postoperative and chemotherapy-induced nausea/vomiting, as well as postoperative dental pain. Less convincing data support AP's efficacy for chronic pain conditions, including headache, fibromyalgia and low back pain. There is no evidence that AP is effective in treating addiction, insomnia, obesity, asthma or stroke deficits. AP seems to be efficacious for alleviating experimental pain by increasing pain thresholds in human subjects and it appears to activate analgesic brain mechanisms through the release of neurohumoral factors, some of which can be inhibited by the opioid antagonist naloxone. In contrast to placebo analgesia, AP-related pain relief takes some time to develop and to resolve. Furthermore, repetitive use of AP analgesia can result in tolerance that demonstrates cross-tolerance with morphine. However, it appears that not all forms of AP are equally effective for providing analgesia. In particular, electro-AP seems to best deliver stimuli that activate powerful opioid and nonopioid analgesic mechanisms. Thus, future carefully controlled clinical trials using adequate electro-AP may be able to provide the necessary evidence for relevant analgesia in chronic pain conditions, such as headache, fibromyalgia, irritable bowel syndrome and low back pain. PMID:16734514

  4. Decreased pain sensitivity among people with schizophrenia: a meta-analysis of experimental pain induction studies.

    PubMed

    Stubbs, Brendon; Thompson, Trevor; Acaster, Sarah; Vancampfort, Davy; Gaughran, Fiona; Correll, Christoph U

    2015-11-01

    Patients with schizophrenia report reduced pain sensitivity in clinical studies, but experimental studies are required to establish pain sensitivity as a potential endophenotype. We conducted a systematic review of electronic databases from database inception until April 15, 2015, including experimental studies investigating pain among patients with schizophrenia spectrum disorder vs healthy controls. A random-effect meta-analysis yielding Hedges' g ±95% confidence intervals (CIs) as the effect size (ES) measure was conducted. Primary outcome was a pooled composite of pain threshold and pain tolerance; secondary outcomes included these parameters individually, plus sensory threshold, physiological pain response, and pain intensity or unpleasantness. Across 17 studies, patients with schizophrenia spectrum disorder (n = 387; age, 30.7 ± 6.9 years; females, 31.9%; illness duration, 7.0 ± 5.7 years) were compared with controls (n = 483; age, 29.5 ± 7.4 years; females, 31.0%). Patients had elevated pain threshold/pain tolerance vs controls (ES = 0.583; 95% CI, 0.212-0.954; P = 0.002; studies = 15). Results were similar in antipsychotic-free individuals (ES = 0.599; 95% CI, 0.291-0.907; P < 0.0001; studies = 8), with trend-level significance in antipsychotic-treated individuals (ES = 0.566; 95% CI, -0.007 to 1.125; P = 0.047; studies = 9). Likewise, patients with schizophrenia had increased pain tolerance (ES = 0.566; 95% CI, 0.235-0.897; P = 0.0001; studies = 6), sensory threshold (ES = 1.16; 95% CI, 0.505-1.727; P < 0.0001; studies = 5), and pain threshold (ES = 0.696; 95% CI, 0.407-0.986; P < 0.001; studies = 9), as well as reduced physiological response to noxious stimuli (ES = 0.456; 95% CI, 0.131-0.783; P = 0.006) and pain intensity/unpleasantness ratings (ES = 0.547; 95% CI, 0.146-0.949; P = 0.008). Findings were similarly significant in antipsychotic-free patients with schizophrenia (analysable parameters = 4) and antipsychotic-treated individuals (analysable

  5. The transcendental meditation technique and acute experimental pain.

    PubMed

    Mills, W W; Farrow, J T

    1981-04-01

    The Transcendental Meditation (TM) technique decreases the distress associated with the experience of acute experimental pain. Fifteen advanced mediators and 15 controls were administered the cold pressor test before and after a 20 minute period of meditation (TM group) or relaxation (control group). Verbal reports of the intensity of pain sensation and pain distress were obtained at intervals during the cold pressor trials. Skin resistance and heart rate were measured throughout. The mean distress level for the TM group was significantly lower than controls during both trials; the mean pain sensation level for the TM group did not differ significantly from controls during either trial. Heart rate and skin resistant changed for both groups in the expected manner, with no significant differences between groups. The validity, implications, and possible causes of these results are discussed.

  6. Nonpainful wide-area compression inhibits experimental pain

    PubMed Central

    Honigman, Liat; Bar-Bachar, Ofrit; Yarnitsky, David; Sprecher, Elliot; Granovsky, Yelena

    2016-01-01

    Abstract Compression therapy, a well-recognized treatment for lymphoedema and venous disorders, pressurizes limbs and generates massive non-noxious afferent sensory barrages. The aim of this study was to study whether such afferent activity has an analgesic effect when applied on the lower limbs, hypothesizing that larger compression areas will induce stronger analgesic effects, and whether this effect correlates with conditioned pain modulation (CPM). Thirty young healthy subjects received painful heat and pressure stimuli (47°C for 30 seconds, forearm; 300 kPa for 15 seconds, wrist) before and during 3 compression protocols of either SMALL (up to ankles), MEDIUM (up to knees), or LARGE (up to hips) compression areas. Conditioned pain modulation (heat pain conditioned by noxious cold water) was tested before and after each compression protocol. The LARGE protocol induced more analgesia for heat than the SMALL protocol (P < 0.001). The analgesic effect interacted with gender (P = 0.015). The LARGE protocol was more efficient for females, whereas the MEDIUM protocol was more efficient for males. Pressure pain was reduced by all protocols (P < 0.001) with no differences between protocols and no gender effect. Conditioned pain modulation was more efficient than the compression-induced analgesia. For the LARGE protocol, precompression CPM efficiency positively correlated with compression-induced analgesia. Large body area compression exerts an area-dependent analgesic effect on experimental pain stimuli. The observed correlation with pain inhibition in response to robust non-noxious sensory stimulation may suggest that compression therapy shares similar mechanisms with inhibitory pain modulation assessed through CPM. PMID:27152691

  7. Between-muscle differences in the adaptation to experimental pain.

    PubMed

    Hug, François; Hodges, Paul W; van den Hoorn, Wolbert; Tucker, Kylie

    2014-11-15

    This study aimed to determine whether muscle stress (force per unit area) can be redistributed between individual heads of the quadriceps muscle when pain is induced into one of these heads. Elastography was used to measure muscle shear elastic modulus (an index of muscle stress). Electromyography (EMG) was recorded from vastus lateralis (VL), vastus medialis (VM), and rectus femoris (RF). In experiment I (n = 20), participants matched a knee extension force, and thus any reduction of stress within the painful muscle would require compensation by other muscles. In experiment II (n = 13), participants matched VL EMG amplitude and were free to vary external force such that intermuscle compensation would be unnecessary to maintain the experimental task. In experiments I and II, pain was induced by injection of hypertonic saline into VM or RF. Experiment III aimed to establish whether voluntary drive to the individual muscles could be controlled independently. Participants (n = 13) were asked to voluntarily reduce activation of VM or RF while maintaining knee extension force. During VM pain, there was no change in shear elastic modulus (experiments I and II) or EMG amplitude of VM (experiment II). In contrast, RF pain was associated with a reduction in RF elastic modulus (experiments I and II: -8 to -17%) and EMG amplitude (experiment II). Participants could voluntarily reduce EMG amplitude of RF (-26%; P = 0.003) but not VM (experiment III). These results highlight between-muscle differences in adaptation to pain that might be explained by their function (monoarticular vs. biarticular) and/or the neurophysiological constraints associated to their activation.

  8. Electromyographic response of shoulder muscles to acute experimental subacromial pain.

    PubMed

    Sole, Gisela; Osborne, Hamish; Wassinger, Craig

    2014-08-01

    This study investigated effects of experimentally-induced subacromial pain, induced via hypertonic saline injection, on shoulder muscles activity. Electromyographic activity of 20 healthy participants was assessed for humeral elevation and descent for the control and experimental pain conditions, using fine wire electrodes for subscapularis and supraspinatus and surface electrodes for middle deltoid, upper trapezius, lower trapezius, infraspinatus, and serratus anterior. Normalized mean amplitudes were analyzed for each muscle for four phases for elevation and descent, respectively. Repeated measures analysis of variances (ANOVAs) were used to determine differences between muscle activity in the control and experimental condition for the four phases of elevation and descent. Differences for mean normalized amplitudes were not significant during humeral elevation. Increased activity was found for the pain condition for serratus anterior and middle deltoid during the first (120-90°) and third (60-30°) parts and decreased activity for infraspinatus in the second half of descent (60-0°). No significant differences were found during descent for upper and lower trapezius, subscapularis and supraspinatus. While increased serratus anterior activity during 60-30° of descent may be protective, increased middle deltoid and decreased infraspinatus activity during the same range may threaten subacromial tissues in that range. Overall the changes in muscle activation were individual specific, particularly during the concentric elevation phase. PMID:24685367

  9. Ultrasound guided, painful electrical stimulation of lumbar facet joint structures: an experimental model of acute low back pain.

    PubMed

    O'Neill, Søren; Graven-Nielsen, Thomas; Manniche, Claus; Arendt-Nielsen, Lars

    2009-07-01

    Quantitative sensory testing has indicated generalized muscle hyperalgesia in patients with chronic low back pain. The temporal development of such hyperalgesia is not well understood. The aim of the present study was to demonstrate whether generalized muscle hyperalgesia can develop within minutes of acute low back pain using a new experimental model of lumbar facet joint pain. Thirteen healthy volunteers were included and baseline pressure pain thresholds were assessed at eight separate sites, outside the area of evoked low back and referred pain. Using ultrasonography, two electrode needles were placed either side of a lumbar facet joint (right L3-4) and used to induce experimental low back pain for 10 min with continuous stimulation. Thresholds, stimulus-response relationships, distribution and quality of the electrically induced pain were recorded. Electrical facet joint stimulation induced low back pain and pain referral into the anterior leg, ipsilaterally, proximal to the knee, similar to what is observed clinically. Pressure pain thresholds did not change significantly before, during and after facet joint stimulation. In conclusion, we describe a novel model of acute experimental low back pain and demonstrate that generalized hyperalgesia did not develop within minutes of acute low back pain. PMID:19376652

  10. Multisite, multimodal neuroimaging of chronic urological pelvic pain: Methodology of the MAPP Research Network.

    PubMed

    Alger, Jeffry R; Ellingson, Benjamin M; Ashe-McNalley, Cody; Woodworth, Davis C; Labus, Jennifer S; Farmer, Melissa; Huang, Lejian; Apkarian, A Vania; Johnson, Kevin A; Mackey, Sean C; Ness, Timothy J; Deutsch, Georg; Harris, Richard E; Clauw, Daniel J; Glover, Gary H; Parrish, Todd B; Hollander, Jan den; Kusek, John W; Mullins, Chris; Mayer, Emeran A

    2016-01-01

    The Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network is an ongoing multi-center collaborative research group established to conduct integrated studies in participants with urologic chronic pelvic pain syndrome (UCPPS). The goal of these investigations is to provide new insights into the etiology, natural history, clinical, demographic and behavioral characteristics, search for new and evaluate candidate biomarkers, systematically test for contributions of infectious agents to symptoms, and conduct animal studies to understand underlying mechanisms for UCPPS. Study participants were enrolled in a one-year observational study and evaluated through a multisite, collaborative neuroimaging study to evaluate the association between UCPPS and brain structure and function. 3D T1-weighted structural images, resting-state fMRI, and high angular resolution diffusion MRI were acquired in five participating MAPP Network sites using 8 separate MRI hardware and software configurations. We describe the neuroimaging methods and procedures used to scan participants, the challenges encountered in obtaining data from multiple sites with different equipment/software, and our efforts to minimize site-to-site variation. PMID:27408791

  11. Multisite, multimodal neuroimaging of chronic urological pelvic pain: Methodology of the MAPP Research Network.

    PubMed

    Alger, Jeffry R; Ellingson, Benjamin M; Ashe-McNalley, Cody; Woodworth, Davis C; Labus, Jennifer S; Farmer, Melissa; Huang, Lejian; Apkarian, A Vania; Johnson, Kevin A; Mackey, Sean C; Ness, Timothy J; Deutsch, Georg; Harris, Richard E; Clauw, Daniel J; Glover, Gary H; Parrish, Todd B; Hollander, Jan den; Kusek, John W; Mullins, Chris; Mayer, Emeran A

    2016-01-01

    The Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network is an ongoing multi-center collaborative research group established to conduct integrated studies in participants with urologic chronic pelvic pain syndrome (UCPPS). The goal of these investigations is to provide new insights into the etiology, natural history, clinical, demographic and behavioral characteristics, search for new and evaluate candidate biomarkers, systematically test for contributions of infectious agents to symptoms, and conduct animal studies to understand underlying mechanisms for UCPPS. Study participants were enrolled in a one-year observational study and evaluated through a multisite, collaborative neuroimaging study to evaluate the association between UCPPS and brain structure and function. 3D T1-weighted structural images, resting-state fMRI, and high angular resolution diffusion MRI were acquired in five participating MAPP Network sites using 8 separate MRI hardware and software configurations. We describe the neuroimaging methods and procedures used to scan participants, the challenges encountered in obtaining data from multiple sites with different equipment/software, and our efforts to minimize site-to-site variation.

  12. The effect of a new multimodal perioperative anesthetic regimen on postoperative pain, side effects, rehabilitation, and length of hospital stay after total joint arthroplasty.

    PubMed

    Peters, Christopher L; Shirley, Brayton; Erickson, Jill

    2006-09-01

    This study evaluated the effect of a new multimodal perioperative anesthetic and pain management strategy for primary total hip (THA) and total knee arthroplasty (TKA). Two cohorts of 50 consecutive THA and 50 TKA patients from before and after initiation of the new protocol were compared. The protocol involved scheduled oral narcotics, cyclooxygenase-2 inhibitors, no intrathecal narcotics, femoral nerve catheters for TKAs, and local anesthetic wound infiltration. Use of patient-controlled analgesia was discouraged. Physical therapy was attempted on the day of surgery. The demographic data, surgical procedure, and implants were similar. There were statistically significant improvements after the protocol regarding rest-pain scores post-operative day (POD) 1 and 2, total narcotic consumption, distance walked POD 1 and 2, and length of stay. There were no significant differences in complications. Implementation of this new multimodal perioperative protocol combined with early mobilization for TKA and THA patients has shortened length of stay, improved pain control, and accomplished therapy goals sooner with less narcotic consumption.

  13. Experimental reduction of pain catastrophizing modulates pain report but not spinal nociception as verified by mediation analyses.

    PubMed

    Terry, Ellen L; Thompson, Kathryn A; Rhudy, Jamie L

    2015-08-01

    Pain catastrophizing is associated with enhanced pain; however, the mechanisms by which it modulates pain are poorly understood. Evidence suggests that catastrophizing modulates supraspinal processing of pain but does not modulate spinal nociception (as assessed by nociceptive flexion reflex [NFR]). Unfortunately, most NFR studies have been correlational. To address this, this study experimentally reduced catastrophizing to determine whether it modulates spinal nociception (NFR). Healthy pain-free participants (N = 113) were randomly assigned to a brief 30-minute catastrophizing reduction manipulation or a control group that received pain education. Before and after manipulations, 2 types of painful stimuli were delivered to elicit (1) NFR (single trains of stimuli) and (2) temporal summation of NFR (3 stimulations at 2 Hz). After each set of stimuli, participants were asked to report their pain intensity and unpleasantness, as well as their situation-specific catastrophizing. Manipulation checks verified that catastrophizing was effectively reduced. Furthermore, pain intensity and unpleasantness to both stimulation types were reduced by the catastrophizing manipulation, effects that were mediated by catastrophizing. Although NFRs were not affected by the catastrophizing manipulation, temporal summation of NFR was reduced. However, this effect was not mediated by catastrophizing. These results indicate that reductions in catastrophizing lead to reductions in pain perception but do not modulate spinal nociception and provides further evidence that catastrophizing modulates pain at the supraspinal, not the spinal, level.

  14. Pain perception in people with Down syndrome: a synthesis of clinical and experimental research

    PubMed Central

    McGuire, Brian E.; Defrin, Ruth

    2015-01-01

    People with an intellectual disability experience both acute and chronic pain with at least the same frequency as the general population. However, considerably less is known about the pain perception of people with Down syndrome. In this review paper, we evaluated the available clinical and experimental evidence. Some experimental studies of acute pain have indicated that pain threshold was higher than normal but only when using a reaction time method to measure pain sensitivity. However, when reaction time is not part of the calculation of the pain threshold, pain sensitivity in people with Down syndrome is in fact lower than normal (more sensitive to pain). Clinical studies of chronic pain have shown that people with an intellectual disability experience chronic pain and within that population, people with Down syndrome also experience chronic pain, but the precise prevalence of chronic pain in Down syndrome has yet to be established. Taken together, the literature suggests that people with Down syndrome experience pain, both acute and chronic, with at least the same frequency as the rest of the population. Furthermore, the evidence suggests that although acute pain expression appears to be delayed, once pain is registered, there appears to be a magnified pain response. We conclude by proposing an agenda for future research in this area. PMID:26283936

  15. Validation and application of a core set of patient-relevant outcome domains to assess the effectiveness of multimodal pain therapy (VAPAIN): a study protocol

    PubMed Central

    Kaiser, Ulrike; Kopkow, Christian; Deckert, Stefanie; Sabatowski, Rainer; Schmitt, Jochen

    2015-01-01

    Introduction Multimodal pain therapy (MPT) has been established accounting for biopsychosocial consideration in diagnostic and therapy. MPT seems to be effective, but comparability of studies is limited due to diversity of study designs and outcome measurements. The presented study aims to develop a core outcome set consisting of a minimum of outcome measures deemed necessary for medical and therapeutic decision-making, which must be measured in all clinical trials and non-randomised intervention studies. Methods and analysis The study consists of several parts. First, the development and recommendation of preliminary core outcome domains will be based on results of a systematic review and structured online surveys. Participants of the expert panel are representatives of methodological, medical, physiotherapeutic, psychotherapeutic profession and patients suffering from chronic pain (n=25). Subsequently, candidate instruments to measure preliminary core outcome domains will be recommended by these experts. Therefore, systematic reviews on measurement properties of preliminary outcome measures will be conducted and finalised in a consensus meeting. Consented instruments and lacking psychometric properties of relevant instruments will be addressed and validated in the following part, a prospective multicentre study in multimodal pain centres on approximately 300 patients with chronic pain. Based on all previous results, a core outcome set for MPT measured in effectiveness studies and daily recordkeeping will be finalised by consensus. Statistical analyses will be performed according to methodological standards (COSMIN). Ethics and dissemination The methods and procedure of the study are developed in compliance with the ethical principles of the Helsinki Declaration and Good Epidemiologic Practice. Recruitment of study participants will require approval of the study by the responsible ethics committee and signed informed consent from each participant. Pseudonymised

  16. Sex differences in experimental pain among healthy children: a systematic review and meta-analysis.

    PubMed

    Boerner, Katelynn E; Birnie, Kathryn A; Caes, Line; Schinkel, Meghan; Chambers, Christine T

    2014-05-01

    Sex differences in response to experimental pain are commonly reported in systematic reviews in the adult literature. The objective of the present research was to conduct a systematic review and meta-analysis of sex differences in healthy children's responses to experimental pain (e.g., cold pressor, heat pain, pressure pain) and, where possible, to conduct analyses separately for children and adolescents. A search was conducted of electronic databases for published papers in English of empirical research using experimental pain tasks to examine pain-related outcomes in healthy boys and girls between 0 and 18 years of age. Eighty articles were eligible for inclusion and were coded to extract information relevant to sex differences. The systematic review indicated that, across different experimental pain tasks, the majority of studies reported no significant differences between boys and girls on pain-related outcomes. However, the meta-analysis of available combined data found that girls reported significantly higher cold pressor pain intensity compared to boys in studies where the mean age of participants was greater than 12 years. Additionally, a meta-analysis of heat pain found that boys had significantly higher tolerance than girls overall, and boys had significantly higher heat pain threshold than girls in studies where the mean age of participants was 12 years or younger. These findings suggest that developmental stage may be relevant for understanding sex differences in pain.

  17. Human experimental pain models: A review of standardized methods in drug development

    PubMed Central

    Reddy, K. Sunil kumar; Naidu, M. U. R.; Rani, P. Usha; Rao, T. Ramesh Kumar

    2012-01-01

    Human experimental pain models are essential in understanding the pain mechanisms and appear to be ideally suited to test analgesic compounds. The challenge that confronts both the clinician and the scientist is to match specific treatments to different pain-generating mechanisms and hence reach a pain treatment tailored to each individual patient. Experimental pain models offer the possibility to explore the pain system under controlled settings. Standardized stimuli of different modalities (i.e., mechanical, thermal, electrical, or chemical) can be applied to the skin, muscles, and viscera for a differentiated and comprehensive assessment of various pain pathways and mechanisms. Using a multimodel-multistructure testing, the nociception arising from different body structures can be explored and modulation of specific biomarkers by new and existing analgesic drugs can be profiled. The value of human experimental pain models is to link animal and clinical pain studies, providing new possibilities for designing successful clinical trials. Spontaneous pain, the main compliant of the neuropathic patients, but currently there is no human model available that would mimic chronic pain. Therefore, current human pain models cannot replace patient studies for studying efficacy of analgesic compounds, although being helpful for proof-of-concept studies and dose finding. PMID:23626642

  18. Adult attachment and reports of pain in experimentally-induced pain.

    PubMed

    Andrews, Nicole Emma; Meredith, Pamela Joy; Strong, Jenny

    2011-05-01

    Attachment theory has been proposed as a framework for understanding the development of chronic pain, with evidence supporting the overrepresentation of insecure attachment styles in chronic pain populations and links between insecure attachment and factors known to impact one's ability to cope with pain. The present study sought to extend two earlier studies exploring the relationships between adult attachment and communication of an acute pain experience, in anticipation of providing insight into individual differences in vulnerability in development of chronic pain. It was hypothesised that: (a) fearful attachment would be associated with perceptions of the pain as less intense, and (b) anxious attachment would be associated with lower pain thresholds. A convenience sample of 82 healthy adults completed self-report measures of attachment, neuroticism, and negative affect prior to taking part in a coldpressor pain inducement task. Results demonstrated that fearful attachment was associated with lower levels of pain intensity throughout the coldpressor task. In addition, dismissing attachment was also associated with less intense pain, as well as increased coldpressor endurance (tolerance) in the presence of a known assessor. These associations were retained after controlling for measures of neuroticism, negative affect, age, and social desirability. The results of this study are consistent with the proposition that fearful and dismissing individuals tend to mask their underlying distress caused by the pain experience, potentially leading to difficulties coping with pain over time.

  19. The role of experimentally-induced subacromial pain on shoulder strength and throwing accuracy.

    PubMed

    Wassinger, Craig A; Sole, Gisela; Osborne, Hamish

    2012-10-01

    Shoulder injuries often comprise two separate yet related components, structural tissue damage and pain. The role of each of these components on shoulder function is difficult to ascertain. Experimental pain models allow the assessment of consequences of localized pain when applied to healthy individuals. By understanding the role of pain on shoulder function, clinicians will be able to more efficiently assess and treat shoulder injuries. The objective of the study was to evaluate the role of experimentally-induced sub-acromial pain on shoulder isokinetic rotational strength and throwing accuracy. This was a block counterbalanced, crossover, repeated measures study design utilizing 20 individuals without self-reported shoulder or cervical pathology. Shoulder function was measured with and without experimental pain injection (2 mL of 5% hypertonic saline) in the sub-acromial space. Functional tasks consisted of shoulder rotational strength utilizing isokinetic testing and throwing accuracy via the functional throwing performance index. The hypertonic saline induced moderate pain levels in all participants (4.3-5.1/10). Normalized shoulder internal (t = 3.76, p = 0.001) and external (t = 3.12, p = 0.006) rotation strength were both diminished in the painful condition compared to the pain free condition. Throwing accuracy was also reduced while the participants experienced pain (t = 3.99, p = 0.001). Moderate levels of experimental shoulder pain were sufficient to negatively influence shoulder strength and throwing accuracy in participants without shoulder pathology.

  20. Effects of coping statements on experimental pain in chronic pain patients

    PubMed Central

    Roditi, Daniela; Robinson, Michael E; Litwins, Nola

    2009-01-01

    The present study measured the effects of catastrophizing self-statements and positive coping self-statements on cold pressor-induced pain. Participants were 58 adult chronic pain patients with current facial pain. It was hypothesized that catastrophizing would lead to a decrease in pain endurance whereas positive coping would lead to an increase in pain endurance. It was also hypothesized that catastrophizing would lead to an increase in peak pain intensity whereas positive coping would lead to a decrease in peak pain intensity. At pretest, participants submerged their nondominant hand in the cold pressor. Pain sensitivity ranges (PSR) were subsequently determined by calculating the difference between tolerance and threshold times. Ratings of peak pain intensity were measured using a pressure sensitive bladder/transducer. Participants underwent random assignment to either a catastrophizing group or a positive coping self-statement group. ANCOVA results revealed that on average, participants employing catastrophizing statements as a coping strategy experienced significantly lower PSR (M = 35.53, SD = 39.71) compared to participants employing positive coping self-statements (M = 73.70, SD = 86.14) when controlling for pretest PSR. Group assignment had no significant influence on peak pain intensity ratings. Thus, our results reveal that manipulation of coping causes changes in pain endurance. PMID:21197299

  1. Muscle pain: animal and human experimental and clinical studies.

    PubMed

    Marchettini, P

    1993-10-01

    The search for the identification of the sensory apparatus encoding muscle pain sensation in humans is recounted. Basic neurophysiologic animal studies, leading to a description of slowly conducting afferent from muscle and definition of high threshold polymodal muscle nociceptors, and pioneer psychophysic human studies together with recent microneurographic experiments in humans are described. The phenomena of muscle pain broad localization and distant referral are discussed, and clinical implications are extrapolated to interpret muscle pain as a localizing sign of mononeuropathy or radiculopathy. The identification of human muscle nociceptors has defined the scientific standard to test emerging clinical descriptions having muscle pain as a symptom.

  2. Naturally occurring muscle pain during exercise: assessment and experimental evidence.

    PubMed

    Cook, D B; O'Connor, P J; Eubanks, S A; Smith, J C; Lee, M

    1997-08-01

    The objectives were: (i) to present a method for assessing muscle pain during exercise, (ii) to provide reliability and validity data in support of the measurement tool, (iii) to test whether leg muscle pain threshold during exercise was related to a commonly used measure of pain threshold pain during test, (iv) to examine the relationship between pain and exertion ratings, (v) to test whether leg muscle pain is related to performance, and (vi) to test whether a large dose of aspirin would delay leg muscle pain threshold and/or reduce pain ratings during exercise. In study 1, seven females and seven males completed three 1-min cycling bouts at three different randomly ordered power outputs. Pain was assessed using a 10-point pain scale. High intraclass correlations (R from 0.88 to 0.98) indicated that pain intensity could be rated reliably using the scale. In study 2, 11 college-aged males (age 21.3 +/- 1.3 yr) performed a ramped (24 W.min-1) maximal cycle ergometry test. A button was depressed when leg muscle pain threshold was reached. Pain threshold occurred near 50% of maximal capacity: 50.3 (+/- 12.9% Wmax), 48.6 (+/- 14.8% VO2max), and 55.8 (+/- 12.9% RPEmax). Pain intensity ratings obtained following pain threshold were positively accelerating function of the relative exercise intensity. Volitional exhaustion was associated with pain ratings of 8.2 (+/- 2.5), a value most closely associated with the verbal anchor "very strong pain." In study 3, participants completed the same maximal exercise test as in study 2 as well as leg cycling at 60 rpm for 8 s at four randomly ordered power outputs (100, 150, 200, and 250 W) on a separate day. Pain and RPE ratings were significantly lower during the 8-s bouts compared to those obtained at the same power outputs during the maximal cycle test. The results suggest that noxious metabolites of muscle contraction play a role in leg muscle pain during exercise. In study 4, moderately active male subjects (N = 19) completed

  3. Sex, Gender, and Pain: A Review of Recent Clinical and Experimental Findings

    PubMed Central

    Fillingim, Roger B.; King, Christopher D.; Ribeiro-Dasilva, Margarete C.; Rahim-Williams, Bridgett; Riley, Joseph L.

    2009-01-01

    Sex-related influences on pain and analgesia have become a topic of tremendous scientific and clinical interest, especially in the last 10 to 15 years. Members of our research group published reviews of this literature more than a decade ago, and the intervening time period has witnessed robust growth in research regarding sex, gender, and pain. Therefore, it seems timely to revisit this literature. Abundant evidence from recent epidemiologic studies clearly demonstrates that women are at substantially greater risk for many clinical pain conditions, and there is some suggestion that postoperative and procedural pain may be more severe among women than men. Consistent with our previous reviews, current human findings regarding sex differences in experimental pain indicate greater pain sensitivity among females compared with males for most pain modalities, including more recently implemented clinically relevant pain models such as temporal summation of pain and intramuscular injection of algesic substances. The evidence regarding sex differences in laboratory measures of endogenous pain modulation is mixed, as are findings from studies using functional brain imaging to ascertain sex differences in pain-related cerebral activation. Also inconsistent are findings regarding sex differences in responses to pharmacologic and non-pharmacologic pain treatments. The article concludes with a discussion of potential biopsychosocial mechanisms that may underlie sex differences in pain, and considerations for future research are discussed. Perspective This article reviews the recent literature regarding sex, gender, and pain. The growing body of evidence that has accumulated in the past 10 to 15 years continues to indicate substantial sex differences in clinical and experimental pain responses, and some evidence suggests that pain treatment responses may differ for women versus men. PMID:19411059

  4. Perception of experimental pain is reduced after provoked waking from rapid eye movement sleep.

    PubMed

    Daya, Vivek G; Bentley, Alison J

    2010-06-01

    Patients with chronic pain often complain of pain when they wake at night, but the accuracy of their perception of the pain after waking at night is unknown. While cognitive functions are reduced for a short time after waking from sleep, a situation known as sleep inertia, it is unclear how sleep inertia may affect the perception of pain. We investigated the effects of sleep inertia on the perception of experimentally induced pain. Fourteen male volunteers were exposed to a randomized thermal heat stimulus of 43.1 degrees C 'hot' and 46.5 degrees C 'hurting' during provoked waking from Stage 2 sleep, slow wave sleep and rapid eye movement (REM) sleep. Subjects rated their pain on awakening on a Visual Analogue Scale at 30 s after awakening and each minute thereafter for 5 min. We found no change in pain perception over the 5-min period irrespective of temperature used or sleep stage. However, perceived pain when awoken abruptly from REM sleep was significantly lower than the awake score for both the hot (P = 0.0069) and hurting (P = 0.0025) temperatures. Pain perception when woken from Stage 2 sleep or slow wave sleep was not significantly different from perception when awake. Our findings indicate that sleep inertia reduces pain perception when awoken abruptly from REM. This suggests that patients who wake up in pain either perceive accurately the pain they are experiencing, or at worst underestimate the level of pain if woken from REM sleep.

  5. The effects of slow breathing on affective responses to pain stimuli: an experimental study.

    PubMed

    Zautra, Alex J; Fasman, Robert; Davis, Mary C; Craig, Arthur D Bud

    2010-04-01

    This study examined whether breathing rate affected self-reported pain and emotion following thermal pain stimuli in women with fibromyalgia syndrome (FM: n=27) or age-matched healthy control women (HC: n=25). FM and HC were exposed to low and moderate thermal pain pulses during paced breathing at their normal rate and one-half their normal rate. Thermal pain pulses were presented in four blocks of four trials. Each block included exposure to both mild and moderate pain trials, and periods of both normal and slow paced breathing. Pain intensity and unpleasantness were recorded immediately following each pain trial, and positive and negative affect were assessed at the end of each block of trials. Compared to normal breathing, slow breathing reduced ratings of pain intensity and unpleasantness, particularly for moderately versus mildly painful thermal stimuli. The effects of slow breathing on pain ratings were less reliable for FM patients than for HCs. Slow versus normal breathing decreased negative affect ratings following thermal pain pulses for both groups, and increased positive affect reports, but only for healthy controls with high trait negative affect. Participants who reported higher levels of trait positive affect prior to the experiment showed greater decreases in negative affect as a result of slow versus normal breathing. These experimental findings provide support for prior reports on the benefits of yogic breathing and mindful Zen meditation for pain and depressed affect. However, chronic pain patients may require more guidance to obtain therapeutic benefit from reduced breathing rates.

  6. Experimental pain processing in individuals with cognitive impairment: current state of the science.

    PubMed

    Defrin, Ruth; Amanzio, Martina; de Tommaso, Marina; Dimova, Violeta; Filipovic, Sasa; Finn, David P; Gimenez-Llort, Lydia; Invitto, Sara; Jensen-Dahm, Christina; Lautenbacher, Stefan; Oosterman, Joukje M; Petrini, Laura; Pick, Chaim G; Pickering, Gisele; Vase, Lene; Kunz, Miriam

    2015-08-01

    Cognitive impairment (CI) can develop during the course of ageing and is a feature of many neurological and neurodegenerative diseases. Many individuals with CI have substantial, sustained, and complex health care needs, which frequently include pain. However, individuals with CI can have difficulty communicating the features of their pain to others, which in turn presents a significant challenge for effective diagnosis and treatment of their pain. Herein, we review the literature on responsivity of individuals with CI to experimental pain stimuli. We discuss pain responding across a large number of neurological and neurodegenerative disorders in which CI is typically present. Overall, the existing data suggest that pain processing is altered in most individuals with CI compared with cognitively intact matched controls. The precise nature of these alterations varies with the type of CI (or associated clinical condition) and may also depend on the type of pain stimulation used and the type of pain responses assessed. Nevertheless, it is clear that regardless of the etiology of CI, patients do feel noxious stimuli, with more evidence for hypersensitivity than hyposensitivity to these stimuli compared with cognitively unimpaired individuals. Our current understanding of the neurobiological mechanisms underpinning these alterations is limited but may be enhanced through the use of animal models of CI, which also exhibit alterations in nociceptive responding. Further research using additional behavioural indices of pain is warranted. Increased understanding of altered experimental pain processing in CI will facilitate the development of improved diagnostic and therapeutic approaches for pain in individuals with CI.

  7. Experimental pain processing in individuals with cognitive impairment: current state of the science.

    PubMed

    Defrin, Ruth; Amanzio, Martina; de Tommaso, Marina; Dimova, Violeta; Filipovic, Sasa; Finn, David P; Gimenez-Llort, Lydia; Invitto, Sara; Jensen-Dahm, Christina; Lautenbacher, Stefan; Oosterman, Joukje M; Petrini, Laura; Pick, Chaim G; Pickering, Gisele; Vase, Lene; Kunz, Miriam

    2015-08-01

    Cognitive impairment (CI) can develop during the course of ageing and is a feature of many neurological and neurodegenerative diseases. Many individuals with CI have substantial, sustained, and complex health care needs, which frequently include pain. However, individuals with CI can have difficulty communicating the features of their pain to others, which in turn presents a significant challenge for effective diagnosis and treatment of their pain. Herein, we review the literature on responsivity of individuals with CI to experimental pain stimuli. We discuss pain responding across a large number of neurological and neurodegenerative disorders in which CI is typically present. Overall, the existing data suggest that pain processing is altered in most individuals with CI compared with cognitively intact matched controls. The precise nature of these alterations varies with the type of CI (or associated clinical condition) and may also depend on the type of pain stimulation used and the type of pain responses assessed. Nevertheless, it is clear that regardless of the etiology of CI, patients do feel noxious stimuli, with more evidence for hypersensitivity than hyposensitivity to these stimuli compared with cognitively unimpaired individuals. Our current understanding of the neurobiological mechanisms underpinning these alterations is limited but may be enhanced through the use of animal models of CI, which also exhibit alterations in nociceptive responding. Further research using additional behavioural indices of pain is warranted. Increased understanding of altered experimental pain processing in CI will facilitate the development of improved diagnostic and therapeutic approaches for pain in individuals with CI. PMID:26181216

  8. Effect of experimental muscle pain on maximal voluntary activation of human biceps brachii muscle.

    PubMed

    Khan, Serajul I; McNeil, Chris J; Gandevia, Simon C; Taylor, Janet L

    2011-09-01

    Muscle pain has widespread effects on motor performance, but the effect of pain on voluntary activation, which is the level of neural drive to contracting muscle, is not known. To determine whether induced muscle pain reduces voluntary activation during maximal voluntary contractions, voluntary activation of elbow flexors was assessed with both motor-point stimulation and transcranial magnetic stimulation over the motor cortex. In addition, we performed a psychophysical experiment to investigate the effect of induced muscle pain across a wide range of submaximal efforts (5-75% maximum). In all studies, elbow flexion torque was recorded before, during, and after experimental muscle pain by injection of 1 ml of 5% hypertonic saline into biceps. Injection of hypertonic saline evoked deep pain in the muscle (pain rating ∼5 on a scale from 0 to 10). Experimental muscle pain caused a small (∼5%) but significant reduction of maximal voluntary torque in the motor-point and motor cortical studies (P < 0.001 and P = 0.045, respectively; n = 7). By contrast, experimental muscle pain had no significant effect on voluntary activation when assessed with motor-point and motor cortical stimulation although voluntary activation tested with motor-point stimulation was reduced by ∼2% in contractions after pain had resolved (P = 0.003). Furthermore, induced muscle pain had no significant effect on torque output during submaximal efforts (P > 0.05; n = 6), which suggests that muscle pain did not alter the relationship between the sense of effort and production of voluntary torque. Hence, the present study suggests that transient experimental muscle pain in biceps brachii has a limited effect on central motor pathways. PMID:21737829

  9. Antihyperalgesic effect of pentoxifylline on experimental inflammatory pain.

    PubMed

    Vale, Mariana L; Benevides, Verônica M; Sachs, Daniela; Brito, Gerly A C; da Rocha, Francisco A C; Poole, Stephen; Ferreira, Sérgio H; Cunha, Fernando Q; Ribeiro, Ronaldo A

    2004-12-01

    The antihyperalgesic effect of pentoxifylline was investigated in three experimental pain models. Pentoxifylline (0.5-1.6 mg kg(-1)) given 30 min before the stimulus significantly inhibited the writhing response induced by the intraperitoneal (i.p.) administration of either acetic acid (-90%) or zymosan (-83%), but not that of iloprost, in mice, as well as the zymosan-induced articular hyperalgesia in the zymosan arthritis in rats (-50%). Pentoxifylline also inhibited the mechanical hypernociception in rats induced by the intraplantar injection of either carrageenin (-81%), bradykinin (-56%) or tumor necrosis factor alpha (TNF-alpha; -46%), but not that induced by interleukin-1beta (IL-1beta) or prostaglandin E(2) (PGE(2)). Pentoxifylline did not inhibit the nociceptive response in the hot plate test in mice. Further, the antinociceptive effect of pentoxifylline in the writhing test in mice and the zymosan-induced articular hyperalgesia were not reversed by the coadministration of the opioid receptor antagonist naloxone. Thus, pentoxifylline antinociceptive effect is probably not mediated at a central level. Pentoxifylline significantly reduced TNF-alpha (-43%) and IL-1beta (-42%) concentrations in the joint exudates of rats stimulated by intra-articular injection of zymosan and the production of both cytokines (-66 and -86%, respectively) by mouse peritoneal macrophages stimulated in vivo with zymosan as well as the expression of TNF-alpha at the tissue level in carrageenin-injected rat paws. In conclusion, the antinociceptive activity of pentoxifylline is associated with the inhibition of the release of both TNF-alpha and IL-1beta.

  10. Isometric force production parameters during normal and experimental low back pain conditions

    PubMed Central

    Descarreaux, Martin; Blouin, Jean-Sébastien; Teasdale, Normand

    2005-01-01

    Background The control of force and its between-trial variability are often taken as critical determinants of motor performance. Subjects performed isometric trunk flexion and extension forces without and with experiment pain to examine if pain yields changes in the control of trunk forces. The objective of this study is to determine if experimental low back pain modifies trunk isometric force production. Methods Ten control subjects participated in this study. They were required to exert 50 and 75% of their isometric maximal trunk flexion and extension torque. In a learning phase preceding the non painful and painful trials, visual and verbal feedbacks were provided. Then, subjects were asked to perform 10 trials without any feedback. Time to peak torque, time to peak torque variability, peak torque variability as well as constant and absolute error in peak torque were calculated. Time to peak and peak dF/dt were computed to determine if the first peak of dF/dt could predict the peak torque achieved. Results Absolute and constant errors were higher in the presence of a painful electrical stimulation. Furthermore, peak torque variability for the higher level of force was increased with in the presence of experimental pain. The linear regressions between peak dF/dt, time to peak dF/dt and peak torque were similar for both conditions. Experimental low back pain yielded increased absolute and constant errors as well as a greater peak torque variability for the higher levels of force. The control strategy, however, remained the same between the non painful and painful condition. Cutaneous pain affects some isometric force production parameters but modifications of motor control strategies are not implemented spontaneously. Conclusions It is hypothesized that adaptation of motor strategies to low back pain is implemented gradually over time. This would enable LBP patients to perform their daily tasks with presumably less pain and more accuracy. PMID:15703067

  11. Vitamin D, Race, and Experimental Pain Sensitivity in Older Adults with Knee Osteoarthritis

    PubMed Central

    Glover, T.L.; Goodin, B.R.; Horgas, A.L.; Kindler, L.L.; King, C.D.; Sibille, K.T.; Peloquin, C.A.; Riley, J.L.; Staud, R.; Bradley, L.A.; Fillingim, R.B.

    2012-01-01

    Objective Low levels of serum circulating 25-hydroxyvitamin D have been correlated with many health conditions, including chronic pain. Recent clinical practice guidelines define vitamin D levels < 20 ng/mL as deficient and values of 21–29 ng/mL as insufficient. Vitamin D insufficiency, including the most severe levels of deficiency, is more prevalent in black Americans. Ethnic and race group differences have been reported in both clinical and experimental pain, with black Americans reporting increased pain. The purpose of this study was to examine whether variation in vitamin D levels contribute to race differences in knee osteoarthritic pain. Methods The sample consisted of 94 participants (75% female), including 45 blacks and 49 whites with symptomatic knee osteoarthritis. Average age was 55.8 years (range 45–71 years). Participants completed a questionnaire on knee osteoarthritic symptoms and underwent quantitative sensory testing, including measures of heat and mechanical pain sensitivity. Results Blacks had significantly lower levels of vitamin D compared to whites, demonstrated greater clinical pain, and showed greater sensitivity to mechanical and heat pain. Low levels of vitamin D predicted increased experimental pain sensitivity, but did not predict self-reported clinical pain. Group differences in vitamin D significantly predicted group differences in heat pain and pressure pain thresholds on the index knee and ipsilateral forearm. Conclusion These data demonstrate race differences in experimental pain are mediated by differences in vitamin D level. Vitamin D deficiency may be a risk factor for increased knee osteoarthritic pain in black Americans. PMID:23135697

  12. Multimodal imaging reveals temporal and spatial microglia and matrix metalloproteinase activity after experimental stroke

    PubMed Central

    Zinnhardt, Bastian; Viel, Thomas; Wachsmuth, Lydia; Vrachimis, Alexis; Wagner, Stefan; Breyholz, Hans-Jörg; Faust, Andreas; Hermann, Sven; Kopka, Klaus; Faber, Cornelius; Dollé, Frédéric; Pappata, Sabina; Planas, Anna M; Tavitian, Bertrand; Schäfers, Michael; Sorokin, Lydia M; Kuhlmann, Michael T; Jacobs, Andreas H

    2015-01-01

    Stroke is the most common cause of death and disability from neurologic disease in humans. Activation of microglia and matrix metalloproteinases (MMPs) is involved in positively and negatively affecting stroke outcome. Novel, noninvasive, multimodal imaging methods visualizing microglial and MMP alterations were employed. The spatio-temporal dynamics of these parameters were studied in relation to blood flow changes. Micro positron emission tomography (μPET) using [18F]BR-351 showed MMP activity within the first days after transient middle cerebral artery occlusion (tMCAo), followed by increased [18F]DPA-714 uptake as a marker for microglia activation with a maximum at 14 days after tMCAo. The inflammatory response was spatially located in the infarct core and in adjacent (penumbral) tissue. For the first time, multimodal imaging based on PET, single photon emission computed tomography, and magnetic resonance imaging revealed insight into the spatio-temporal distribution of critical parameters of poststroke inflammation. This allows further evaluation of novel treatment paradigms targeting the postischemic inflammation. PMID:26126867

  13. CCR2 chemokine receptor signaling mediates pain in experimental osteoarthritis

    PubMed Central

    Miller, Rachel E.; Tran, Phuong B.; Das, Rosalina; Ghoreishi-Haack, Nayereh; Ren, Dongjun; Miller, Richard J.; Malfait, Anne-Marie

    2012-01-01

    Osteoarthritis is one of the leading causes of chronic pain, but almost nothing is known about the mechanisms and molecules that mediate osteoarthritis-associated joint pain. Consequently, treatment options remain inadequate and joint replacement is often inevitable. Here, we use a surgical mouse model that captures the long-term progression of knee osteoarthritis to longitudinally assess pain-related behaviors and concomitant changes in the innervating dorsal root ganglia (DRG). We demonstrate that monocyte chemoattractant protein (MCP)-1 (CCL2) and its high-affinity receptor, chemokine (C-C motif) receptor 2 (CCR2), are central to the development of pain associated with knee osteoarthritis. After destabilization of the medial meniscus, mice developed early-onset secondary mechanical allodynia that was maintained for 16 wk. MCP-1 and CCR2 mRNA, protein, and signaling activity were temporarily up-regulated in the innervating DRG at 8 wk after surgery. This result correlated with the presentation of movement-provoked pain behaviors, which were maintained up to 16 wk. Mice that lack Ccr2 also developed mechanical allodynia, but this started to resolve from 8 wk onwards. Despite severe allodynia and structural knee joint damage equal to wild-type mice, Ccr2-null mice did not develop movement-provoked pain behaviors at 8 wk. In wild-type mice, macrophages infiltrated the DRG by 8 wk and this was maintained through 16 wk after surgery. In contrast, macrophage infiltration was not observed in Ccr2-null mice. These observations suggest a key role for the MCP-1/CCR2 pathway in establishing osteoarthritis pain. PMID:23185004

  14. Memory and pain: tests of mood congruity and state dependent learning in experimentally induced and clinical pain.

    PubMed

    Pearce, S A; Isherwood, S; Hrouda, D; Richardson, P H; Erskine, A; Skinner, J

    1990-11-01

    The associative network theory of memory [2] is outlined along with the concepts of mood congruity and state dependent learning. Two experiments are reported which investigate the occurrence of these effects where memory for pain is concerned. In experiment 1 the performance of 25 chronic pain patients was compared with that of 25 non-patient controls on a test involving both immediate and delayed recall of a mixed list of stimulus words of 3 types: pain-related, negative or neutral. No significant group differences were found in overall rates of immediate recall. As predicted, however, pain patients recalled more pain-related words than non-patient controls (P less than 0.001). On delayed recall the same significant group x word-type interaction was obtained (P less than 0.02), but in addition the non-patient controls recalled significantly more words overall (P less than 0.02). These results provide some evidence for the occurrence of a mood congruity effect. Experiment 2 investigated state dependent learning and mood congruity effects in experimentally induced pain. Twenty volunteer subjects were allocated to 1 of 4 conditions in which a wordlist (as in experiment 1) was presented following either a painful stimulus (cold pressor test) or a non-painful one (warm water) and was then recalled immediately following further exposure to stimulus conditions which were congruent with the original stimulus (warm/warm and cold/cold conditions) or non-congruent (warm/cold and cold/warm conditions). A 3-way split plot ANOVA yielded no significant main effects for group or word-type, but a significant interaction emerged between state at encoding and at recall (P less than 0.04).(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Argument for the need of investigation of the relationship between body fatness and experimental pain sensitivity.

    PubMed

    Astita, Rehab A; Tashani, Osama A; Sharp, Duncan; Johnson, Mark I

    2015-01-01

    In this communication, we argue about the need for an extensive investigation of the relationship between body fatness and fat distribution and experimental pain to explore the factors that might contribute to the increased prevalence of pain conditions in obese individuals. PMID:26085491

  16. Experimental tonic hand pain modulates the corticospinal plasticity induced by a subsequent hand deafferentation.

    PubMed

    Mavromatis, N; Gagné, M; Voisin, J I A V; Reilly, K T; Mercier, C

    2016-08-25

    Sensorimotor reorganization is believed to play an important role in the development and maintenance of phantom limb pain, but pain itself might modulate sensorimotor plasticity induced by deafferentation. Clinical and basic research support this idea, as pain prior to amputation increases the risk of developing post-amputation pain. The aim of this study was to examine the influence of experimental tonic cutaneous hand pain on the plasticity induced by temporary ischemic hand deafferentation. Sixteen healthy subjects participated in two experimental sessions (Pain, No Pain) in which transcranial magnetic stimulation was used to assess corticospinal excitability in two forearm muscles (flexor carpi radialis and flexor digitorum superficialis) before (T0, T10, T20, and T40) and after (T60 and T75) inflation of a cuff around the wrist. The cuff was inflated at T45 in both sessions and in the Pain session capsaicin cream was applied on the dorsum of the hand at T5. Corticospinal excitability was significantly greater during the Post-inflation phase (p=0.002) and increased similarly in both muscles (p=0.861). Importantly, the excitability increase in the Post-inflation phase was greater for the Pain than the No-Pain condition (p=0.006). Post-hoc analyses revealed a significant difference between the two conditions during the Post-inflation phase (p=0.030) but no difference during the Pre-inflation phase (p=0.601). In other words, the corticospinal facilitation was greater when pain was present prior to cuff inflation. These results indicate that pain can modulate the plasticity induced by another event, and could partially explain the sensorimotor reorganization often reported in chronic pain populations. PMID:27291642

  17. Gut pain reactions in man: an experimental investigation using short and long duration transmucosal electrical stimulation.

    PubMed

    Arendt-Nielsen, L; Drewes, A M; Hansen, J B; Tage-Jensen, U

    1997-02-01

    Visceral pain is a substantial, clinical problem but unfortunately few experimental models are available to study this phenomenon in man. In the present study we inserted a stimulation catheter 5-10 cm into the ileo-sigmoidostomy of nine patients. The catheter contained six small, flexible electrodes separated by 4 mm. The gut was stimulated by single burst, repeated burst (five stimuli delivered at 2 Hz), or continuous burst stimuli (4 Hz for 30, 60, 90, and 120 s). The sensation (ST), pain detection (PDT), and pain tolerance (PTT) thresholds to single/repeated burst stimuli were determined. The location/size/sensitivity of referred pain after repeated/continuous stimulation were characterized. The brain potentials to single burst stimuli and to increasing stimulus intensity were measured. ST to single burst stimuli was easy to determine (8 mA) and to reproduce. The patients found it difficult to determine the PDT and PTT to single burst stimuli, however both thresholds were easily determined for repeated burst stimuli. The pain thresholds to single burst stimuli were twice as high as the thresholds to repeated burst stimuli, indicating the importance of central temporal summation for visceral pain. Minor changes in the stimulus location resulted in changes of the referred pain projection site. The words most frequently selected (78%) from the McGill Pain Questionnaire to describe repeated burst stimulations were shooting, pricking, flashing, and boring. The amplitude of the brain potentials increased at increasing stimulus intensity. A stimulus intensity giving an initial pain rating of around 5 on a 0-10 visual analog scale (VAS) was used for continuous stimulation. A general increase of the pain intensity and the area of referred pain was found during this stimulation. It was concluded that electrical stimulation of the human gut provokes pain and especially long sequences of visceral stimuli are adequate to evoke referred pain mimicking pain profiles of

  18. Antinociceptive Interaction of Tramadol with Gabapentin in Experimental Mononeuropathic Pain.

    PubMed

    Miranda, Hugo F; Noriega, Viviana; Prieto, Juan Carlos; Zanetta, Pilar; Castillo, Rodrigo; Aranda, Nicolás; Sierralta, Fernando

    2016-08-01

    Neuropathic pain is the result of injury to the nervous system, and different animal models have been established to meet the manifestations of neuropathy. The pharmacotherapy for neuropathic pain includes gabapentin and tramadol, but these are only partially effective when given alone. The aim of this study was to assess the antinociceptive interaction between both drugs using the isobolographic analysis and changes of the IL-1β concentration in a mouse model of neuropathic pain (partial sciatic nerve ligation or PSNL). The i.p. administration of gabapentin (5-100 mg/kg) or tramadol (12.5-100 mg/kg) displayed a dose-dependent antinociception in the hot plate assay of PSNL mice, and effects induced by gabapentin with tramadol were synergistic. Administration of gabapentin or tramadol reversed significantly the increase in the concentration of IL-1β induced by PSNL after either 7 or 14 days and their combination was significantly more potent in reversing the elevated concentration of IL-1β. The synergism obtained by the co-administration of gabapentin and tramadol is proposed to result from action on different mechanisms in pain pathways. Gabapentin or tramadol or their combination modulates the expression of pro-inflammatory cytokine, IL-1β, in a model of mice PSNL which could be due to an inhibition of glial function.

  19. Experimenter Effects on Pain Reporting in Women Vary across the Menstrual Cycle

    PubMed Central

    Vigil, Jacob M.; DiDomenico, Jared; Strenth, Chance; Coulombe, Patrick; Kruger, Eric; Mueller, Andrea A.; Guevara Beltran, Diego; Adams, Ian

    2015-01-01

    Background. Separate lines of research have shown that menstrual cycling and contextual factors such as the gender of research personnel influence experimental pain reporting. Objectives. This study examines how brief, procedural interactions with female and male experimenters can affect experimentally reported pain (cold pressor task, CPT) across the menstrual cycle. Methods. Based on the menstrual calendars 94 naturally cycling women and 38 women using hormonal contraceptives (Mage = 19.83,  SD = 3.09) were assigned to low and high fertility groups. This assignment was based on estimates of their probability of conception given their current cycle day. Experimenters (12 males, 7 females) engaged in minimal procedural interactions with participants before the CPT was performed in solitude. Results. Naturally cycling women in the high fertility group showed significantly higher pain tolerance (81 sec, d = .79) following interactions with a male but not a female experimenter. Differences were not found for women in the low fertility or contraceptive groups. Discussion. The findings illustrate that menstrual functioning moderates the effect that experimenter gender has on pain reporting in women. Conclusion. These findings have implications for standardizing pain measurement protocols and understanding how basic biopsychosocial mechanisms (e.g., person-perception systems) can modulate pain experiences. PMID:25892990

  20. Clinical pharmacology of analgesics assessed with human experimental pain models: bridging basic and clinical research

    PubMed Central

    Oertel, Bruno Georg; Lötsch, Jörn

    2013-01-01

    The medical impact of pain is such that much effort is being applied to develop novel analgesic drugs directed towards new targets and to investigate the analgesic efficacy of known drugs. Ongoing research requires cost-saving tools to translate basic science knowledge into clinically effective analgesic compounds. In this review we have re-examined the prediction of clinical analgesia by human experimental pain models as a basis for model selection in phase I studies. The overall prediction of analgesic efficacy or failure of a drug correlated well between experimental and clinical settings. However, correct model selection requires more detailed information about which model predicts a particular clinical pain condition. We hypothesized that if an analgesic drug was effective in an experimental pain model and also a specific clinical pain condition, then that model might be predictive for that particular condition and should be selected for development as an analgesic for that condition. The validity of the prediction increases with an increase in the numbers of analgesic drug classes for which this agreement was shown. From available evidence, only five clinical pain conditions were correctly predicted by seven different pain models for at least three different drugs. Most of these models combine a sensitization method. The analysis also identified several models with low impact with respect to their clinical translation. Thus, the presently identified agreements and non-agreements between analgesic effects on experimental and on clinical pain may serve as a solid basis to identify complex sets of human pain models that bridge basic science with clinical pain research. PMID:23082949

  1. Common trace elements alleviate pain in an experimental mouse model.

    PubMed

    Tamba, Bogdan I; Leon, Maria-Magdalena; Petreus, Tudor

    2013-04-01

    Trace elements represent a group of essential metals or metaloids necessary for life, present in minute amounts. Analgesic adjuvants can enhance the effect of other pain drugs or be used for pain control themselves. Previous studies on the effects of trace elements on nociception and their potential use as analgesic adjuvants have yielded conflicting results. In this study, we tested the hypothesis that three vital trace elements (Zn²⁺, Mg²⁺, Cu²⁺) have direct antinociceptive effects. Groups of eight Swiss mice were intraperitoneally (i.p) injected with incremental concentrations of Zn²⁺ sulfate (0.5, 2.0 mg/kg), Zn²⁺ citrate (0.125, 0.5 mg/kg), Mg²⁺ chloride (37.5, 75, 150 mg/kg), Cu²⁺ chloride (0.5, 1.0, 2.0 mg/kg), and Cu²⁺ sulfate (0.5, 1.0 mg/kg) or saline (control). Evaluations were made by hot plate (HP) and tail flick (TF) tests for central antinociceptive effect, writhing test (WT) for visceral antinociceptive effect, and activity cage (AC) test for spontaneous behavior. Zn²⁺ induced pain inhibition in HP/TF tests (up to 17%) and WT (up to 25%), with no significant differences among the salts used. Mg²⁺ salts induced pain inhibition for all performed tests (up to 85% in WT). Cu²⁺ salts showed antinociceptive effects for HP/TF (up to 28.6%) and WT (57.28%). Only Mg²⁺ and Cu²⁺ salts have displayed significant effects in AC (Mg²⁺ anxiolytic/depressant effect; Cu²⁺ anxiolytic effect). We interpret these data to mean that all tested trace elements induced antinociceptive effects in central and visceral pain tests. Our data indicate the potential use of these cheap adjuvants in pain therapy. PMID:23362003

  2. Multimodality Imaging of the Painful Elbow: Current Imaging Concepts and Image-Guided Treatments for the Injured Thrower's Elbow.

    PubMed

    Gustas, Cristy N; Lee, Kenneth S

    2016-09-01

    Elbow pain in overhead sport athletes is not uncommon. Repetitive throwing can lead to chronic overuse and/or acute injury to tendons, ligaments, bones, or nerves about the elbow. A thorough history and physical examination of the thrower's elbow frequently establishes the diagnosis for pain. Imaging can provide additional information when the clinical picture is unclear or further information is necessary for risk stratification and treatment planning. This article focuses on current imaging concepts and image-guided treatments for injuries commonly affecting the adult throwing athlete's elbow. PMID:27545422

  3. Multimodal imaging with hybrid semiconductor detectors Timepix for an experimental MRI-SPECT system

    NASA Astrophysics Data System (ADS)

    Zajicek, J.; Jakubek, J.; Burian, M.; Vobecky, M.; Fauler, A.; Fiederle, M.; Zwerger, A.

    2013-01-01

    An increasing number of clinical applications are being based on multimodal imaging systems (MIS), including anatomical (CT, MRI) and functional (PET, SPECT) techniques to provide complex information in a single image. CT with one of the scintigraphic methods (PET or SPECT) is nowadays a combination of choice for clinical practice and it is mostly used in cardiography and tumour diagnostics. Combination with MRI is also being implemented as no radiation dose is imparted to the patient and it is possible to gain higher structural resolution of soft tissues (brain imaging). A major disadvantage of such systems is inability to operate scintillators with photomultipliers (used for detection of γ rays) in presence of high magnetic fields. In this work we present the application of the semiconductor pixel detector for SPECT method in combination with MR imaging. We propose a novel approach based on MRI compatible setup with CdTe pixel sensor Timepix and non-conductive collimator. Measurements were performed on high proton-density (PD) phantom (1H) with an embedded radioisotopic source inside the shielded RF coil by MRI animal scanner (4.7 T). Our results pave the way for a combined MRI-SPECT system. The project was performed in the framework of the Medipix Collaboration.

  4. Sex differences in how social networks and relationship quality influence experimental pain sensitivity.

    PubMed

    Vigil, Jacob M; Rowell, Lauren N; Chouteau, Simone; Chavez, Alexandre; Jaramillo, Elisa; Neal, Michael; Waid, David

    2013-01-01

    This is the first study to examine how both structural and functional components of individuals' social networks may moderate the association between biological sex and experimental pain sensitivity. One hundred and fifty-two healthy adults (mean age = 22yrs., 53% males) were measured for cold pressor task (CPT) pain sensitivity (i.e., intensity ratings) and core aspects of social networks (e.g., proportion of friends vs. family, affection, affirmation, and aid). Results showed consistent sex differences in how social network structures and intimate relationship functioning modulated pain sensitivity. Females showed higher pain sensitivity when their social networks consisted of a higher proportion of intimate types of relationship partners (e.g., kin vs. non kin), when they had known their network partners for a longer period of time, and when they reported higher levels of logistical support from their significant other (e.g., romantic partner). Conversely, males showed distinct patterns in the opposite direction, including an association between higher levels of logistical support from one's significant other and lower CPT pain intensity. These findings show for the first time that the direction of sex differences in exogenous pain sensitivity is likely dependent on fundamental components of the individual's social environment. The utility of a social-signaling perspective of pain behaviors for examining, comparing, and interpreting individual and group differences in experimental and clinical pain reports is discussed. PMID:24223836

  5. Analgesic efficacy of lidocaine and multimodal analgesia for chest tube removal: A randomized trial study1

    PubMed Central

    Pinheiro, Valdecy Ferreira de Oliveira; da Costa, José Madson Vidal; Cascudo, Marcelo Matos; Pinheiro, Ênio de Oliveira; Fernandes, Maria Angela Ferreira; de Araujo, Ivonete Batista

    2015-01-01

    Objective: to assess the analgesic efficacy of subcutaneous lidocaine and multimodal analgesia for chest tube removal following heart surgery. Methods: sixty volunteers were randomly allocated in two groups; 30 participants in the experimental group were given 1% subcutaneous lidocaine, and 30 controls were given a multimodal analgesia regime comprising systemic anti-inflammatory agents and opioids. The intensity and quality of pain and trait and state anxiety were assessed. The association between independent variables and final outcome was assessed by means of the Chi-squared test with Yates' correction and Fisher's exact test. Results: the groups did not exhibit significant difference with respect to the intensity of pain upon chest tube removal (p= 0.47). The most frequent descriptors of pain reported by the participants were pressing, sharp, pricking, burning and unbearable. Conclusion: the present study suggests that the analgesic effect of the subcutaneous administration of 1% lidocaine combined with multimodal analgesia is most efficacious. PMID:26625989

  6. No Effect of a Single Session of Transcranial Direct Current Stimulation on Experimentally Induced Pain in Patients with Chronic Low Back Pain – An Exploratory Study

    PubMed Central

    Luedtke, Kerstin; May, Arne; Jürgens, Tim P.

    2012-01-01

    Transcranial direct current stimulation (tDCS) has been shown to modulate cortical excitability. A small number of studies suggested that tDCS modulates the response to experimental pain paradigms. No trials have been conducted to evaluate the response of patients already suffering from pain, to an additional experimental pain before and after tDCS. The present study investigated the effect of a single session of anodal, cathodal and sham stimulation (15 mins/1 mA) over the primary motor cortex on the perceived intensity of repeated noxious thermal and electrical stimuli and on elements of quantitative sensory testing (thermal pain and perception thresholds) applied to the right hand in 15 patients with chronic low back pain. The study was conducted in a double-blind sham-controlled and cross-over design. No significant alterations of pain ratings were found. Modalities of quantitative sensory testing remained equally unchanged. It is therefore hypothesized that a single 15 mins session of tDCS at 1 mA may not be sufficient to alter the perception of experimental pain and in patients with chronic pain. Further studies applying repetitive tDCS to patients with chronic pain are required to fully answer the question whether experimental pain perception may be influenced by tDCS over the motor cortex. PMID:23189136

  7. No effect of a single session of transcranial direct current stimulation on experimentally induced pain in patients with chronic low back pain--an exploratory study.

    PubMed

    Luedtke, Kerstin; May, Arne; Jürgens, Tim P

    2012-01-01

    Transcranial direct current stimulation (tDCS) has been shown to modulate cortical excitability. A small number of studies suggested that tDCS modulates the response to experimental pain paradigms. No trials have been conducted to evaluate the response of patients already suffering from pain, to an additional experimental pain before and after tDCS. The present study investigated the effect of a single session of anodal, cathodal and sham stimulation (15 mins/1 mA) over the primary motor cortex on the perceived intensity of repeated noxious thermal and electrical stimuli and on elements of quantitative sensory testing (thermal pain and perception thresholds) applied to the right hand in 15 patients with chronic low back pain. The study was conducted in a double-blind sham-controlled and cross-over design. No significant alterations of pain ratings were found. Modalities of quantitative sensory testing remained equally unchanged. It is therefore hypothesized that a single 15 mins session of tDCS at 1 mA may not be sufficient to alter the perception of experimental pain and in patients with chronic pain. Further studies applying repetitive tDCS to patients with chronic pain are required to fully answer the question whether experimental pain perception may be influenced by tDCS over the motor cortex. PMID:23189136

  8. Assessing efficacy of non-opioid analgesics in experimental pain models in healthy volunteers: an updated review

    PubMed Central

    Staahl, Camilla; Olesen, Anne Estrup; Andresen, Trine; Arendt-Nielsen, Lars; Drewes, Asbjørn Mohr

    2009-01-01

    AIM Experimental pain models may help to evaluate the mechanisms of analgesics and target the clinical indications for their use. This review, the second in a series of two, addresses how the efficacy of non-opioid analgesics have been assessed in human volunteers using experimental pain models. METHODS A literature search was completed for randomized controlled studies that included human experimental pain models, healthy volunteers and non-opioid analgesics. RESULTS Nonsteroidal anti-inflammatory drugs worked against various types of acute pain as well as in hyperalgesia. Analgesia from paracetamol was difficult to detect in experimental pain and the pain needed to be assessed with very sensitive methods like evoked brain potentials. The N-methyl-D-aspartate antagonists exemplified by ketamine generally needed strong, long-lasting or repeated pain in the skin for detectable analgesia, whereas pain in muscle and viscera generally was more easily attenuated. Gabapentin worked well in several models, particularly those inducing hyperalgesia, whereas lamotrigine was weak in modulation of experimental pain. Imipramine attenuated pain in most experimental models, whereas amitriptyline had weaker effects. Delta-9-tetrahydrocannabinol attenuated pain in only a few models. CONCLUSIONS Pain induction and assessment are very important for the sensitivity of the pain models. Generally, experimental pain models need to be designed with careful consideration of the pharmacological mechanisms and pharmacokinetics of analgesics. The drawback with the different study designs is also discussed. This knowledge can aid the decisions that need to be taken when designing experimental pain studies for compounds entering Phase I and II trials. PMID:19740390

  9. Experimental verification of a novel MEMS multi-modal vibration energy harvester for ultra-low power remote sensing nodes

    NASA Astrophysics Data System (ADS)

    Iannacci, J.; Sordo, G.; Serra, E.; Kucera, M.; Schmid, U.

    2015-05-01

    In this work, we discuss the verification and preliminary experimental characterization of a MEMS-based vibration Energy Harvester (EH) design. The device, named Four-Leaf Clover (FLC), is based on a circular-shaped mechanical resonator with four petal-like mass-spring cascaded systems. This solution introduces several mechanical Degrees of Freedom (DOFs), and therefore enables multiple resonant modes and deformation shapes in the vibrations frequency range of interest. The target is to realize a wideband multi-modal EH-MEMS device, that overcomes the typical narrowband working characteristics of standard cantilevered EHs, by ensuring flexible and adaptable power source to ultra-low power electronics for integrated remote sensing nodes (e.g. Wireless Sensor Networks - WSNs) in the Internet of Things (IoT) scenario, aiming to self-powered and energy autonomous smart systems. Finite Element Method simulations of the FLC EH-MEMS show the presence of several resonant modes for vibrations up to 4-5 kHz, and level of converted power up to a few μW at resonance and in closed-loop conditions (i.e. with resistive load). On the other hand, the first experimental tests of FLC fabricated samples, conducted with a Laser Doppler Vibrometer (LDV), proved the presence of several resonant modes, and allowed to validate the accuracy of the FEM modeling method. Such a good accordance holds validity for what concerns the coupled field behavior of the FLC EH-MEMS, as well. Both measurements and simulations performed at 190 Hz (i.e. out of resonance) showed the generation of power in the range of nW (Root Mean Square - RMS values). Further steps of this work will include the experimental characterization in a full range of vibrations, aiming to prove the whole functionality of the FLC EH-MEMS proposed design concept.

  10. The effect of spinal manipulative therapy on experimentally induced pain: a systematic literature review

    PubMed Central

    2012-01-01

    Background Although there is evidence that spinal manipulative therapy (SMT) can reduce pain, the mechanisms involved are not well established. There is a need to review the scientific literature to establish the evidence-base for the reduction of pain following SMT. Objectives To determine if SMT can reduce experimentally induced pain, and if so, if the effect is i) only at the level of the treated spinal segment, ii) broader but in the same general region as SMT is performed, or iii) systemic. Design A systematic critical literature review. Methods A systematic search was performed for experimental studies on healthy volunteers and people without chronic syndromes, in which the immediate effect of SMT was tested. Articles selected were reviewed blindly by two authors. A summary quality score was calculated to indicate level of manuscript quality. Outcome was considered positive if the pain-reducing effect was statistically significant. Separate evidence tables were constructed with information relevant to each research question. Results were interpreted taking into account their manuscript quality. Results Twenty-two articles were included, describing 43 experiments, primarily on pain produced by pressure (n = 27) or temperature (n = 9). Their quality was generally moderate. A hypoalgesic effect was shown in 19/27 experiments on pressure pain, produced by pressure in 3/9 on pain produced by temperature and in 6/7 tests on pain induced by other measures. Second pain provoked by temperature seems to respond to SMT but not first pain. Most studies revealed a local or regional hypoalgesic effect whereas a systematic effect was unclear. Manipulation of a “restricted motion segment” (“manipulable lesion”) seemed not to be essential to analgesia. In relation to outcome, there was no discernible difference between studies with higher vs. lower quality scores. Conclusions These results indicate that SMT has a direct local/regional hypoalgesic effect on

  11. Inflammation-induced pain sensitization in men and women: does sex matter in experimental endotoxemia?

    PubMed Central

    Wegner, Alexander; Elsenbruch, Sigrid; Rebernik, Laura; Roderigo, Till; Engelbrecht, Elisa; Jäger, Marcus; Engler, Harald; Schedlowski, Manfred; Benson, Sven

    2015-01-01

    Abstract A role of the innate immune system is increasingly recognized as a mechanism contributing to pain sensitization. Experimental administration of the bacterial endotoxin lipopolysaccharide (LPS) constitutes a model to study inflammation-induced pain sensitization, but all existing human evidence comes from male participants. We assessed visceral and musculoskeletal pain sensitivity after low-dose LPS administration in healthy men and women to test the hypothesis that women show greater LPS-induced hyperalgesia compared with men. In this randomized, double-blind, placebo-controlled crossover study, healthy men (n = 20) and healthy women using oral contraceptives (n = 20) received an intravenous injection of 0.4 ng/kg body weight LPS or placebo. Pain sensitivity was assessed with established visceral and musculoskeletal pain models (ie, rectal pain thresholds; pressure pain thresholds for different muscle groups), together with a heartbeat perception (interoceptive accuracy) task. Plasma cytokines (tumor necrosis factor-α and interleukin-6) were measured along with state anxiety at baseline and up to 6-hour postinjection. Lipopolysaccharide application led to significant increases in plasma cytokines and state anxiety and decreased interoceptive awareness in men and women (P < 0.001, condition effects), with more pronounced LPS-induced cytokine increases in women (P < 0.05, interaction effects). Although both rectal and pressure pain thresholds were significantly decreased in the LPS condition (all P < 0.05, condition effect), no sex differences in endotoxin-induced sensitization were observed. In summary, LPS-induced systemic immune activation leads to visceral and musculoskeletal hyperalgesia, irrespective of biological sex. These findings support the broad applicability of experimental endotoxin administration as a translational preclinical model of inflammation-induced pain sensitization in both sexes. PMID:26058036

  12. Inflammation-induced pain sensitization in men and women: does sex matter in experimental endotoxemia?

    PubMed

    Wegner, Alexander; Elsenbruch, Sigrid; Rebernik, Laura; Roderigo, Till; Engelbrecht, Elisa; Jäger, Marcus; Engler, Harald; Schedlowski, Manfred; Benson, Sven

    2015-10-01

    A role of the innate immune system is increasingly recognized as a mechanism contributing to pain sensitization. Experimental administration of the bacterial endotoxin lipopolysaccharide (LPS) constitutes a model to study inflammation-induced pain sensitization, but all existing human evidence comes from male participants. We assessed visceral and musculoskeletal pain sensitivity after low-dose LPS administration in healthy men and women to test the hypothesis that women show greater LPS-induced hyperalgesia compared with men. In this randomized, double-blind, placebo-controlled crossover study, healthy men (n = 20) and healthy women using oral contraceptives (n = 20) received an intravenous injection of 0.4 ng/kg body weight LPS or placebo. Pain sensitivity was assessed with established visceral and musculoskeletal pain models (ie, rectal pain thresholds; pressure pain thresholds for different muscle groups), together with a heartbeat perception (interoceptive accuracy) task. Plasma cytokines (tumor necrosis factor-α and interleukin-6) were measured along with state anxiety at baseline and up to 6-hour postinjection. Lipopolysaccharide application led to significant increases in plasma cytokines and state anxiety and decreased interoceptive awareness in men and women (P < 0.001, condition effects), with more pronounced LPS-induced cytokine increases in women (P < 0.05, interaction effects). Although both rectal and pressure pain thresholds were significantly decreased in the LPS condition (all P < 0.05, condition effect), no sex differences in endotoxin-induced sensitization were observed. In summary, LPS-induced systemic immune activation leads to visceral and musculoskeletal hyperalgesia, irrespective of biological sex. These findings support the broad applicability of experimental endotoxin administration as a translational preclinical model of inflammation-induced pain sensitization in both sexes.

  13. Inflammation-induced pain sensitization in men and women: does sex matter in experimental endotoxemia?

    PubMed

    Wegner, Alexander; Elsenbruch, Sigrid; Rebernik, Laura; Roderigo, Till; Engelbrecht, Elisa; Jäger, Marcus; Engler, Harald; Schedlowski, Manfred; Benson, Sven

    2015-10-01

    A role of the innate immune system is increasingly recognized as a mechanism contributing to pain sensitization. Experimental administration of the bacterial endotoxin lipopolysaccharide (LPS) constitutes a model to study inflammation-induced pain sensitization, but all existing human evidence comes from male participants. We assessed visceral and musculoskeletal pain sensitivity after low-dose LPS administration in healthy men and women to test the hypothesis that women show greater LPS-induced hyperalgesia compared with men. In this randomized, double-blind, placebo-controlled crossover study, healthy men (n = 20) and healthy women using oral contraceptives (n = 20) received an intravenous injection of 0.4 ng/kg body weight LPS or placebo. Pain sensitivity was assessed with established visceral and musculoskeletal pain models (ie, rectal pain thresholds; pressure pain thresholds for different muscle groups), together with a heartbeat perception (interoceptive accuracy) task. Plasma cytokines (tumor necrosis factor-α and interleukin-6) were measured along with state anxiety at baseline and up to 6-hour postinjection. Lipopolysaccharide application led to significant increases in plasma cytokines and state anxiety and decreased interoceptive awareness in men and women (P < 0.001, condition effects), with more pronounced LPS-induced cytokine increases in women (P < 0.05, interaction effects). Although both rectal and pressure pain thresholds were significantly decreased in the LPS condition (all P < 0.05, condition effect), no sex differences in endotoxin-induced sensitization were observed. In summary, LPS-induced systemic immune activation leads to visceral and musculoskeletal hyperalgesia, irrespective of biological sex. These findings support the broad applicability of experimental endotoxin administration as a translational preclinical model of inflammation-induced pain sensitization in both sexes. PMID:26058036

  14. Neuronal and immunological basis of action of antidepressants in chronic pain - clinical and experimental studies.

    PubMed

    Mika, Joanna; Zychowska, Magdalena; Makuch, Wioletta; Rojewska, Ewelina; Przewlocka, Barbara

    2013-01-01

    The current knowledge of the pharmacological actions of the tricyclic antidepressants (TCAs) has slowly evolved through their over 40-year history. Chronic pain represents one of the most important public health problems, and antidepressants are an essential part of the therapeutic strategy in addition to classical analgesics. This article reviews the available evidence on the efficacy and safety of antidepressants in chronic pain conditions; namely, headaches, low back pain, fibromyalgia, cancer pain and especially neuropathic pain. TCAs are traditionally the main type of depression medication used to treat chronic pain. Recently, new antidepressants were introduced into clinical use, with a significant reduction in side effects and equivalent efficacy on mood disorders. These new drugs that are effective for chronic pain belong to the tetracyclic antidepressants (TeCAs) group (amoxapine, maprotiline), the serotonin and noradrenaline reuptake inhibitors (SNRIs) group (duloxetine, venlafaxine, milnacipran) and the atypical antidepressants group (bupropion, trazodone, mirtazapine, nefazodone). In this review, we present the available publications on TCAs (amitriptyline, doxepin, imipramine, desipramine, nortriptyline), TeCAs (amoxapine, maprotiline), selective serotonin reuptake inhibitors (SSRIs) (citalopram, fluoxetine, paroxetine), SNRIs (duloxetine, venlafaxine, milnacipran) and atypical antidepressants (bupropion) for the treatment of neuropathic pain. We also review analgesics acting as both opioid receptor agonists and also acting as aminergic reuptake inhibitors. Existing data are insufficient to conclude which of these new classes of antidepressants has the best clinical profile and will be the most effective in the treatment of neuropathic pain; in addition, a lower incidence of side effects should be considered. Increased experimental and translational research is a key for further improvement of the treatment of chronic pain with antidepressants. However

  15. Reorganization of muscle synergies during multidirectional reaching in the horizontal plane with experimental muscle pain

    PubMed Central

    Muceli, Silvia; Falla, Deborah

    2014-01-01

    Muscle pain induces a complex reorganization of the motor strategy which cannot be fully explained by current theories. We tested the hypothesis that the neural control of muscles during reaching in the presence of nociceptive input is determined by a reorganization of muscle synergies with respect to control conditions. Muscle pain was induced by injection of hypertonic saline into the anterior deltoid muscle of eight men. Electromyographic (EMG) signals were recorded from 12 upper limb muscles as subjects performed a reaching task before (baseline) and after the injection of hypertonic (pain) saline, and after the pain sensation vanished. The EMG envelopes were factorized in muscle synergies, and activation signals extracted for each condition. Nociceptive stimulation resulted in a complex muscle reorganization without changes in the kinematic output. The anterior deltoid muscle activity decreased in all subjects while the changes in other muscles were subject specific. Three synergies sufficed to describe the EMG patterns in each condition, suggesting that reaching movements remain modular in the presence of experimental pain. Muscle reorganization in all subjects was accompanied by a change in the activation signals compatible with a change in the central drive to muscles. One, two or three synergies were shared between the baseline and painful conditions, depending on the subject. These results indicate that nociceptive stimulation may induce a reorganization of modular control in reaching. We speculate that such reorganization may be due to the recruitment of synergies specific to the painful condition. PMID:24453279

  16. Duration of Analgesia Induced by Acupuncture-Like TENS on Experimental Heat Pain

    PubMed Central

    Brochu, Marilyne; Dupuis-Michaud, Cynthia; Pagé, Catherine; Popovic, Draga; Simard, Marie-Eve

    2013-01-01

    Background. Acupuncture-like TENS (AL-TENS) is a treatment modality that can be used to temporarily reduce pain. However, there is no clear data in the literature regarding the specific duration of analgesia induced by AL-TENS. Objectives. To describe and quantify the duration and magnitude of AL-TENS analgesia on experimental heat pain in healthy subjects and verify if the duration or magnitude of analgesia induced by the AL-TENS was influenced by the duration of the application of the AL-TENS (15 versus 30 minutes). Methods. A repeated-measures, intrasubject randomized experimental design was used, where each participant was his/her own control. 22 healthy volunteers underwent heat pain stimulations with a contact thermode before (pretest) and after (posttest) AL-TENS application (15 and 30 minutes). Outcome measures included subjective pain during AL-TENS, duration, and magnitude of AL-TENS-induced analgesia. Results. Survival analysis showed that the median duration of AL-TENS analgesia was 10 minutes following the application of either 15 or 30 minutes of AL-TENS. The magnitude of analgesia following either application was comparable at all points in time (P values > 0.05) and ranged between −20% and −36% pain reduction. Conclusion. Only half of the participants still had heat-pain analgesia induced by the AL-TENS at 15 minutes postapplication. PMID:27335882

  17. The effect of experimental low back pain on lumbar muscle activity in people with a history of clinical low back pain: a muscle functional MRI study.

    PubMed

    Danneels, Lieven; Cagnie, Barbara; D'hooge, Roseline; De Deene, Yves; Crombez, Geert; Vanderstraeten, Guy; Parlevliet, Thierry; Van Oosterwijck, Jessica

    2016-02-01

    In people with a history of low back pain (LBP), structural and functional alterations have been observed at several peripheral and central levels of the sensorimotor pathway. These existing alterations might interact with the way the sensorimotor system responds to pain. We examined this assumption by evaluating the lumbar motor responses to experimental nociceptive input of 15 participants during remission of unilateral recurrent LBP. Quantitative T2 images (muscle functional MRI) were taken bilaterally of multifidus, erector spinae, and psoas at several segmental levels (L3 upper and L4 upper and lower endplate) and during several conditions: 1) at rest, 2) upon trunk-extension exercise without pain, and 3) upon trunk-extension exercise with experimental induced pain at the clinical pain-side (1.5-ml intramuscular hypertonic saline injections in erector spinae). Following experimental pain induction, muscle activity levels similarly reduced for all three muscles, on both painful and nonpainful sides, and at multiple segmental levels (P = 0.038). Pain intensity and localization from experimental LBP were similar as during recalled clinical LBP episodes. In conclusion, unilateral and unisegmental experimental LBP exerts a generalized and widespread decrease in lumbar muscle activity during remission of recurrent LBP. This muscle response is consistent with previous observed patterns in healthy people subjected to the same experimental pain paradigm. It is striking that similar inhibitory patterns in response to pain could be observed, despite the presence of preexisting alterations in the lumbar musculature during remission of recurrent LBP. These results suggest that motor output can modify along the course of recurrent LBP.

  18. [Pathophysiology of neuropathic pain: review of experimental models and proposed mechanisms].

    PubMed

    Garcia-Larrea, Luis; Magnin, Michel

    2008-02-01

    Neuropathic pain can be conceptualized as the result of an "aberrant learning" process, associated with maladaptive plasticity of the nervous system. A number of modifications of the peripheral nervous system have been described in animal models of neuropathic pain, but their relation with different symptoms in humans is far from fully understood. We note in particular ectopic discharges in damaged myelinated fibers, abnormal activity in undamaged fibers, overexpression of calcium channels increasing the release of excitatory neurotransmitters, and sympathetic sprouting towards the spinal ganglia. Spinal mechanisms involve central sensitization, kindling and potentiation phenomena. Underlying these phenomena may be connectivity changes--still controversial--of non-nociceptive terminals and variations in the sensitivity of postsynaptic receptors. Also contributing to these pathophysiologic modifications are attenuation of spinal inhibition by selective neuronal loss and the development of inflammatory phenomena, including cytokine secretion by macrophages and glial cells. Changes in the dorsal horn modify the activity of projections towards the brainstem and increase spinal hyperactivity still further by feedback loops. These effects are delayed, suggesting that maintenance of spinal sensitization requires the involvement of mechanisms of descending facilitation involving the brainstem. These phenomena induce changes in the activity of thalamocortical networks, which develop autonomous processes that maintain the pain. The cortical representation of body areas change after nervous lesions, and these changes may correlate with the emergence of pain. Neuropathic allodynia and hyperalgesia are supported by cortical modifications that experimental models reproduce very incompletely. Experimental allodynia and neuropathic allodynia share the activation of the cortical pain matrix as well as the bilateralization of insular activity. However, although experimental

  19. The efficacy of multimodal high-volume wound infiltration in primary total knee replacement in facilitating immediate post-operative pain relief and attainment of early rehabilitation milestones.

    PubMed

    Banerjee, Purnajyoti

    2014-05-01

    Inadequate pain relief after lower limb joint replacement surgery has been a well-recognised limiting factor affecting post-operative mobilisation and length of hospital stay. Multimodal local wound infiltration with local anaesthetics, adrenaline and non-steroidal anti-inflammatory agents can lower the opiate intake, reduce the length of stay and enhance early mobilisation in knee replacement patients. A retrospective review of 64 patients undergoing primary total knee replacement was undertaken. Thirty-two patients (cases) had their wounds infiltrated with ropivacaine, adrenaline and ketorolac by the operating surgeon, intraoperatively. Subsequently, a 19G wound catheter placed into the knee joint. They received two further top-up doses of the same combination at 10 and 20 h post-operatively. This group was compared with a control group of 32 patients who did not receive any local infiltration. Both groups were comparable in terms of BMI and age. Post-operative opiate drug consumption in first 48 h after surgery, length of hospital stays and time taken to mobilise after surgery were recorded. There was significant reduction in opiate consumption in the treatment group with an average consumption of 49.35 mg of morphine compared to 71.48 mg in the control group (p = 0.004). The median length of hospital stay was significantly reduced from 5 days in the control group to 4 days in the treatment group (p = 0.03). The patients in the treatment group mobilised around 19 h earlier (p = 0.001). No major post-operative complications were encountered in either group. Wound infiltration is an effective and safe technique that promotes early rehabilitation and discharge of patients following primary total knee replacement.

  20. Kinesthetic illusions attenuate experimental muscle pain, as do muscle and cutaneous stimulation.

    PubMed

    Gay, André; Aimonetti, Jean-Marc; Roll, Jean-Pierre; Ribot-Ciscar, Edith

    2015-07-30

    In the present study, muscle pain was induced experimentally in healthy subjects by administrating hypertonic saline injections into the tibialis anterior (TA) muscle. We first aimed at comparing the analgesic effects of mechanical vibration applied to either cutaneous or muscle receptors of the TA or to both types simultaneously. Secondly, pain alleviation was compared in subjects in whom muscle tendon vibration evoked kinesthetic illusions of the ankle joint. Muscle tendon vibration, which primarily activated muscle receptors, reduced pain intensity by 30% (p<0.01). In addition, tangential skin vibration reduced pain intensity by 33% (p<0.01), primarily by activating cutaneous receptors. Concurrently stimulating both sensory channels induced stronger analgesic effects (-51%, p<0.01), as shown by the lower levels of electrodermal activity. The strongest analgesic effects of the vibration-induced muscle inputs occurred when illusory movements were perceived (-38%, p=0.01). The results suggest that both cutaneous and muscle sensory feedback reduce muscle pain, most likely via segmental and supraspinal processes. Further clinical trials are needed to investigate these new methods of muscle pain relief. PMID:25935692

  1. Opioid pathways activation mediates the activity of nicorandil in experimental models of nociceptive and inflammatory pain.

    PubMed

    Dutra, Marcela M G B; Nascimento Júnior, Elias B; Godin, Adriana M; Brito, Ana Mercy S; Melo, Ivo S F; Augusto, Paulo S A; Rodrigues, Felipe F; Araújo, Débora P; de Fátima, Ângelo; Coelho, Márcio M; Machado, Renes R

    2015-12-01

    We have previously demonstrated that nicorandil inhibits the second phase of the nociceptive response induced by formaldehyde. In the present study, we evaluated the effects induced by nicorandil in other models of nociceptive and inflammatory pain in mice and also whether opioid pathways activation mediates its activity. As we have previously demonstrated, per os (p.o.) administration of nicorandil (50, 100 or 150mg/kg; -1h) inhibited the second phase of the nociceptive response induced by intraplantar (i.pl.) injection of formaldehyde. Nicorandil (50, 100 or 150mg/kg; p.o., -1h) also exhibited activity in models of inflammatory pain induced by i.pl. injection of carrageenan (300μg) and nociceptive pain induced by exposure to noxious heat (50°C). Intraperitoneal (i.p.) administration of the opioid antagonist naltrexone (1, 5 or 10mg/kg, -30min) attenuated or abolished the antinociceptive activity of nicorandil (100mg/kg, p.o.) in the three experimental pain models. In conclusion, we demonstrate that nicorandil exhibits activity in different models of nociceptive and inflammatory pain. The demonstration that the antinociceptive effect induced by nicorandil is markedly attenuated by an opioid antagonist provides solid information about an important mechanism mediating the activity of this antianginal drug. Altogether, our data suggest that the clinical pain relief induced by nicorandil in heart ischemic conditions may result from both vasodilation and intrinsic analgesic activity. PMID:26522924

  2. Stress and thermoregulation: different sympathetic responses and different effects on experimental pain.

    PubMed

    Fechir, M; Schlereth, T; Kritzmann, S; Balon, S; Pfeifer, N; Geber, C; Breimhorst, M; Eberle, T; Gamer, M; Birklein, F

    2009-10-01

    Stress and thermoregulation both activate the sympathetic nervous system (SNS) but might differently affect pain. Studies investigating possible interactions in patients are problematic because of the high prevalence of SNS disturbances in patients. We therefore analyzed the influence of these different sympathetic challenges on experimentally-induced pain in healthy subjects. SNS was activated in two different ways: by mental stress (Stroop task, mental arithmetic task), and by thermoregulatory stimulation using a water-perfused thermal suit (7 degrees C, 32 degrees C, or 50 degrees C). Attentional effects of the mental stress tasks were controlled by using easy control tasks. Both, stress and thermoregulatory stimuli, robustly activated SNS parameters. However, the patterns of activation were different. While stress co-activated heart rate, blood pressure, peripheral vasoconstriction and sweating, thermal stimulation either increased blood pressure (cold) or heart rate and sweating (warm). Only stress was able to induce a significant reduction of pain. The control tasks neither activated the SNS nor altered pain perception. Our results suggest that (1) different patterns of sympathetic activation can be recorded after stress and thermoregulatory challenges and (2) that only stress is able to interfere with sensation of experimental pain. Whether SNS activation is causally responsible for analgesia needs to be further investigated.

  3. Experimental muscle pain results in reorganization of coordination among trapezius muscle subdivisions during repetitive shoulder flexion.

    PubMed

    Falla, Deborah; Farina, Dario; Graven-Nielsen, Thomas

    2007-04-01

    The aim of the study was to examine the effect of experimental unilateral upper trapezius muscle pain on the relative activation of trapezius muscle subdivisions bilaterally during repetitive movement of the upper limb. Surface EMG signals were detected from nine healthy subjects from the upper, middle and lower divisions of trapezius during a repetitive bilateral shoulder flexion task. Measurements were performed before and after injection of 0.5 ml hypertonic (pain condition) and isotonic (control) saline into the upper division of the right trapezius muscle in two experimental sessions. On the painful side, upper trapezius showed decreased EMG amplitude (average rectified value, ARV) and lower trapezius increased ARV throughout the entire task following the injection of hypertonic saline (40.0 +/- 22.2 vs. 26.0 +/- 17.4 microV, and 12.5 +/- 7.6 vs. 25.6 +/- 14.8 microV, respectively, at the beginning of the contraction). On the side contralateral to pain, greater estimates of ARV were identified for the upper division of trapezius as the task progressed (37.4 +/- 20.2 vs. 52.7 +/- 28.4 microV, at the end of the contraction). Muscle fiber conduction velocity did not change with pain in all three divisions of the right trapezius muscle. The results suggest that local elicitation of nociceptive afferents in the upper division of the trapezius induces reorganization in the coordinated activity of the three subdivisions of the trapezius in repetitive dynamic tasks.

  4. Complex regional pain syndrome (CRPS) or continuous unilateral distal experimental pain stimulation in healthy subjects does not bias visual attention towards one hemifield.

    PubMed

    Filippopulos, Filipp M; Grafenstein, Jessica; Straube, Andreas; Eggert, Thomas

    2015-11-01

    In natural life pain automatically draws attention towards the painful body part suggesting that it interacts with different attentional mechanisms such as visual attention. Complex regional pain syndrome (CRPS) patients who typically report on chronic distally located pain of one extremity may suffer from so-called neglect-like symptoms, which have also been linked to attentional mechanisms. The purpose of the study was to further evaluate how continuous pain conditions influence visual attention. Saccade latencies were recorded in two experiments using a common visual attention paradigm whereby orientating saccades to cued or uncued lateral visual targets had to be performed. In the first experiment saccade latencies of healthy subjects were measured under two conditions: one in which continuous experimental pain stimulation was applied to the index finger to imitate a continuous pain situation, and one without pain stimulation. In the second experiment saccade latencies of patients suffering from CRPS were compared to controls. The results showed that neither the continuous experimental pain stimulation during the experiment nor the chronic pain in CRPS led to an unilateral increase of saccade latencies or to a unilateral increase of the cue effect on latency. The results show that unilateral, continuously applied pain stimuli or chronic pain have no or only very limited influence on visual attention. Differently from patients with visual neglect, patients with CRPS did not show strong side asymmetries of saccade latencies or of cue effects on saccade latencies. Thus, neglect-like clinical symptoms of CRPS patients do not involve the allocation of visual attention.

  5. Guidelines on the recognition of pain, distress and discomfort in experimental animals and an hypothesis for assessment.

    PubMed

    Morton, D B; Griffiths, P H

    1985-04-20

    Under the 1876 Cruelty to Animals Act it is necessary to recognise pain so that an assessment may be made to determine if it is 'an experiment calculated to give pain' and 'to prevent the animal feeling pain'. Under the conditions of the licence it is also necessary to recognise 'severe pain which is likely to endure' and 'suffering considerable pain'. In the White Paper May 1983 (Command 8883) it is stated that: 'in the application of controls the concept of pain should be applied in a wide sense' and 'the Home Secretary's practice has been to interpret the concept of pain to include disease, other disturbances of normal health, adverse change in physiology, discomfort and distress'. The draft European Convention for the Protection of Vertebrate Animals used for Experimental and other Purposes, aims to control, subject to specific exceptions, any experimental or other scientific procedure which 'may cause pain, suffering, distress or lasting harm'. (The White Paper states that UK control will be stricter than the Council of Europe proposals.) Thus, there is a considerable onus on the experimenter to recognise pain (not to define it) and to alleviate it. It is intended that this article should be of help, not only to newcomers inexperienced in the recognition of pain, but also possibly to those relatively experienced workers who may be called upon to evaluate the pain involved in a new model or an individual animal.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Central Pain Processing in Early-Stage Parkinson's Disease: A Laser Pain fMRI Study

    PubMed Central

    Petschow, Christine; Scheef, Lukas; Paus, Sebastian; Zimmermann, Nadine; Schild, Hans H.; Klockgether, Thomas; Boecker, Henning

    2016-01-01

    Background & Objective Pain is a common non-motor symptom in Parkinson’s disease. As dopaminergic dysfunction is suggested to affect intrinsic nociceptive processing, this study was designed to characterize laser-induced pain processing in early-stage Parkinson’s disease patients in the dopaminergic OFF state, using a multimodal experimental approach at behavioral, autonomic, imaging levels. Methods 13 right-handed early-stage Parkinson’s disease patients without cognitive or sensory impairment were investigated OFF medication, along with 13 age-matched healthy control subjects. Measurements included warmth perception thresholds, heat pain thresholds, and central pain processing with event-related functional magnetic resonance imaging (erfMRI) during laser-induced pain stimulation at lower (E = 440 mJ) and higher (E = 640 mJ) target energies. Additionally, electrodermal activity was characterized during delivery of 60 randomized pain stimuli ranging from 440 mJ to 640 mJ, along with evaluation of subjective pain ratings on a visual analogue scale. Results No significant differences in warmth perception thresholds, heat pain thresholds, electrodermal activity and subjective pain ratings were found between Parkinson’s disease patients and controls, and erfMRI revealed a generally comparable activation pattern induced by laser-pain stimuli in brain areas belonging to the central pain matrix. However, relatively reduced deactivation was found in Parkinson’s disease patients in posterior regions of the default mode network, notably the precuneus and the posterior cingulate cortex. Conclusion Our data during pain processing extend previous findings suggesting default mode network dysfunction in Parkinson’s disease. On the other hand, they argue against a genuine pain-specific processing abnormality in early-stage Parkinson’s disease. Future studies are now required using similar multimodal experimental designs to examine pain processing in more advanced

  7. The effect of cognitive bias modification for interpretation on avoidance of pain during an acute experimental pain task.

    PubMed

    Jones, Emma Blaisdale; Sharpe, Louise

    2014-08-01

    Research confirms that patients with chronic pain show a tendency to interpret ambiguous stimuli as pain related. However, whether modifying these interpretive pain biases impacts pain outcomes is unknown. This study aimed to demonstrate that interpretation biases towards pain can be modified, and that changing these biases influences pain outcomes in the cold pressor task. One hundred and six undergraduate students were randomly allocated to receive either threatening or reassuring information regarding the cold pressor. They also were randomly allocated to 1 of 2 conditions in the Ambiguous Scenarios Task, in which they were trained to have either a threatening interpretation of pain (pain bias condition) or a nonthreatening interpretation of pain (no pain bias condition). Therefore, the study had a 2 (threat/reassuring)×2 (pain bias/no pain bias) design. Analyses showed that a bias was induced contingent on condition, and that the threat manipulation was effective. Participants in the pain bias condition hesitated more before doing the cold pressor task than those in the no pain bias condition, as did those in the threat compared with the reassurance condition. The major finding was that interpretive bias mediated the relationship between bias condition and hesitance time, supporting the causal role of interpretive biases for avoidance behaviors in current chronic pain models. No differences were found on other pain outcomes regarding bias or threat, and the efficacy of the bias modification was not impacted by different levels of threat. These results suggest that cognitive bias modification should be further explored as a potential intervention in pain.

  8. Evaluation of pain in rats through facial expression following experimental tooth movement.

    PubMed

    Liao, Lina; Long, Hu; Zhang, Li; Chen, Helin; Zhou, Yang; Ye, Niansong; Lai, Wenli

    2014-04-01

    This study was carried out to evaluate pain in rats by monitoring their facial expressions following experimental tooth movement. Male Sprague-Dawley rats were divided into the following five groups based on the magnitude of orthodontic force applied and administration of analgesics: control; 20 g; 40 g; 80 g; and morphine + 40 g. Closed-coil springs were used to mimic orthodontic forces. The facial expressions of each rat were videotaped, and the resulting rat grimace scale (RGS) coding was employed for pain quantification. The RGS score increased on day 1 but showed no significant change thereafter in the control and 20-g groups. In the 40- and 80-g groups, the RGS scores increased on day 1, peaked on day 3, and started to decrease on day 5. At 14 d, the RGS scores were similar in control and 20-, 40-, and 80-g groups and did not return to baseline. The RGS scores in the morphine + 40-g group were significantly lower than those in the control group. Our results reveal that coding of facial expression is a valid method for evaluation of pain in rats following experimental tooth movement. Inactivated springs (no force) still cause discomfort and result in an increase in the RGS. The threshold force magnitude required to evoke orthodontic pain in rats is between 20 and 40 g.

  9. Within-team Patterns of Communication and Referral in Multimodal Treatment of Chronic Low Back Pain Patients by an Integrative Care Team

    PubMed Central

    O'Connor, Bonnie B.; Eisenberg, David M.; Buring, Julie E.; Liang, Catherine L.; Osypiuk, Kamila; Levy, Donald B.

    2015-01-01

    Background: Nonspecific chronic low back pain (CLBP) is a highly prevalent and costly public health problem with few treatment options that provide consistent and greater than modest benefits. Treatment of CLBP is shifting from unimodal to multimodal and multidisciplinary approaches, including biopsychosocially-based complementary and integrative care. Multidisciplinary approaches require unique levels of communication and coordination amongst clinicians; however, to date few studies have evaluated patterns of communication and decision making amongst clinicians collaborating in the care of challenging patients with CLBP. Methods: As part of an observational study evaluating the effectiveness and cost-effectiveness of an integrative, team-based care model for the treatment of CLBP, we used multiple qualitative research methods to characterize within-team cross-referral and communication amongst jointly-trained practitioners representing diverse biomedical and complementary disciplines. Patterns of communication and coordinated care are summarized for 3 cases of CLBP treated by multiple members (≥3) of an integrative medical team embedded within an academic hospital. Results: Patients were aged from 36 to 88 years with varied comorbidities. Qualitative content analysis revealed 5 emergent themes regarding integrative patient care and treatment decision in this clinic: (1) the fundamental importance of the clinic's formal teamwork training; (2) the critical communicative and collaborative function of regular team meetings; (3) the importance to patient care goals of having the varied disciplines practicing “under one roof”; (4) a universal commitment to understanding and treating patients as whole persons; and (5) a shared philosophy of helping patients to help themselves. These key themes are all interconnected and form the foundation of the clinic's culture. Conclusions: Our qualitative findings provide context for current trends in enhancing patient

  10. Postoperative pain control.

    PubMed

    Lovich-Sapola, Jessica; Smith, Charles E; Brandt, Christopher P

    2015-04-01

    Prevention and control of postoperative pain are essential. Inadequate treatment of postoperative pain continues to be a major problem after many surgeries and leads to worse outcomes, including chronic postsurgical pain. Optimal management of postoperative pain requires an understanding of the pathophysiology of pain, methods available to reduce pain, invasiveness of the procedure, and patient factors associated with increased pain, such as anxiety, depression, catastrophizing, and neuroticism. Use of a procedure-specific, multimodal perioperative pain management provides a rational basis for enhanced postoperative pain control, optimization of analgesia, decrease in adverse effects, and improved patient satisfaction.

  11. Experimental tooth clenching. A model for studying mechanisms of muscle pain.

    PubMed

    Dawson, Andreas

    2013-01-01

    The overall goal of this thesis was to broaden knowledge of pain mechanisms in myofascial temporomandibular disorders (M-TMD). The specific aims were to: Develop a quality assessment tool for experimental bruxism studies (study I). Investigate proprioceptive allodynia after experimental tooth clenching exercises (study II). Evaluate the release of serotonin (5-HT), glutamate, pyruvate, and lactate in healthy subjects (study III) and in patients with M-TMD (study IV), after experimental tooth clenching exercises. In (I), tool development comprised 5 steps: (i) preliminary decisions, (ii) item generation, (iii) face-validity assessment, (iv) reliability and discriminative validity testing, and (v) instrument refinement. After preliminary decisions and a literature review, a list of 52 items to be considered for inclusion in the tool was generated. Eleven experts were invited to participate on the Delphi panel, of which 10 agreed. After four Delphi rounds, 8 items remained and were included in the Quality Assessment Tool for Experimental Bruxism Studies (Qu-ATEBS). Inter-observer reliability was acceptable (k = 0.77), and discriminative validity high (phi coefficient 0.79; P < 0.01). During refinement, 1 item was removed; the final tool comprised 7 items. In (II), 16 healthy females participated in three 60-min sessions, each with 24- and 48-h follow-ups. Participants were randomly assigned to a repetitive experimental tooth clenching task with a clenching level of 10%, 20%, or 40% of maximal voluntary clenching force (MVCF). Pain intensity, fatigue, perceived intensity of vibration (PIV), perceived discomfort (PD), and pressure pain threshold (PPT) were measured throughout. A significant increase in pain intensity and fatigue but not in PD was observed over time. A significant increase in PIV was only observed at 40 min, and PPT decreased significantly over time at 50 and 60 min compared to baseline. In (III), 30 healthy subjects (16 females, and 14 males

  12. Experimental tooth clenching. A model for studying mechanisms of muscle pain.

    PubMed

    Dawson, Andreas

    2013-01-01

    The overall goal of this thesis was to broaden knowledge of pain mechanisms in myofascial temporomandibular disorders (M-TMD). The specific aims were to: Develop a quality assessment tool for experimental bruxism studies (study I). Investigate proprioceptive allodynia after experimental tooth clenching exercises (study II). Evaluate the release of serotonin (5-HT), glutamate, pyruvate, and lactate in healthy subjects (study III) and in patients with M-TMD (study IV), after experimental tooth clenching exercises. In (I), tool development comprised 5 steps: (i) preliminary decisions, (ii) item generation, (iii) face-validity assessment, (iv) reliability and discriminative validity testing, and (v) instrument refinement. After preliminary decisions and a literature review, a list of 52 items to be considered for inclusion in the tool was generated. Eleven experts were invited to participate on the Delphi panel, of which 10 agreed. After four Delphi rounds, 8 items remained and were included in the Quality Assessment Tool for Experimental Bruxism Studies (Qu-ATEBS). Inter-observer reliability was acceptable (k = 0.77), and discriminative validity high (phi coefficient 0.79; P < 0.01). During refinement, 1 item was removed; the final tool comprised 7 items. In (II), 16 healthy females participated in three 60-min sessions, each with 24- and 48-h follow-ups. Participants were randomly assigned to a repetitive experimental tooth clenching task with a clenching level of 10%, 20%, or 40% of maximal voluntary clenching force (MVCF). Pain intensity, fatigue, perceived intensity of vibration (PIV), perceived discomfort (PD), and pressure pain threshold (PPT) were measured throughout. A significant increase in pain intensity and fatigue but not in PD was observed over time. A significant increase in PIV was only observed at 40 min, and PPT decreased significantly over time at 50 and 60 min compared to baseline. In (III), 30 healthy subjects (16 females, and 14 males

  13. Pain in experimental autoimmune encephalitis: a comparative study between different mouse models

    PubMed Central

    2012-01-01

    Background Pain can be one of the most severe symptoms associated with multiple sclerosis (MS) and develops with varying levels and time courses. MS-related pain is difficult to treat, since very little is known about the mechanisms underlying its development. Animal models of experimental autoimmune encephalomyelitis (EAE) mimic many aspects of MS and are well-suited to study underlying pathophysiological mechanisms. Yet, to date very little is known about the sensory abnormalities in different EAE models. We therefore aimed to thoroughly characterize pain behavior of the hindpaw in SJL and C57BL/6 mice immunized with PLP139-151 peptide or MOG35-55 peptide respectively. Moreover, we studied the activity of pain-related molecules and plasticity-related genes in the spinal cord and investigated functional changes in the peripheral nerves using electrophysiology. Methods We analyzed thermal and mechanical sensitivity of the hindpaw in both EAE models during the whole disease course. Qualitative and quantitative immunohistochemical analysis of pain-related molecules and plasticity-related genes was performed on spinal cord sections at different timepoints during the disease course. Moreover, we investigated functional changes in the peripheral nerves using electrophysiology. Results Mice in both EAE models developed thermal hyperalgesia during the chronic phase of the disease. However, whereas SJL mice developed marked mechanical allodynia over the chronic phase of the disease, C57BL/6 mice developed only minor mechanical allodynia over the onset and peak phase of the disease. Interestingly, the magnitude of glial changes in the spinal cord was stronger in SJL mice than in C57BL/6 mice and their time course matched the temporal profile of mechanical hypersensitivity. Conclusions Diverse EAE models bearing genetic, clinical and histopathological heterogeneity, show different profiles of sensory and pathological changes and thereby enable studying the mechanistic basis

  14. Effect of experimentally induced low back pain on postural sway with breathing.

    PubMed

    Smith, Michelle; Coppieters, Michel W; Hodges, Paul W

    2005-09-01

    Although breathing perturbs balance, in healthy individuals little sway is detected in ground reaction forces because small movements of the spine and lower limbs compensate for the postural disturbance. When people have chronic low back pain (LBP), sway at the ground is increased, possibly as a result of reduced compensatory motion of the trunk. The aim of this study was to determine whether postural compensation for breathing is reduced during experimentally induced pain. Subjects stood on a force plate with eyes open, eyes closed, and while breathing with hypercapnoea before and after injection of hypertonic saline into the right lumbar longissimus muscle to induce LBP. Motion of the lumbar spine, pelvis, and lower limbs was measured with four inclinometers fixed over bony landmarks. During experimental pain, motion of the trunk in association with breathing was reduced. However, despite this reduction in motion, there was no increase in postural sway with breathing. These data suggest that increased body sway with breathing in people with chronic LBP is not simply because of reduced trunk movement, but instead, indicates changes in coordination by the central nervous system that are not replicated by experimental nociceptor stimulation.

  15. Endogenous Opioid Antagonism in Physiological Experimental Pain Models: A Systematic Review

    PubMed Central

    Werner, Mads U.; Pereira, Manuel P.; Andersen, Lars Peter H.; Dahl, Jørgen B.

    2015-01-01

    Opioid antagonists are pharmacological tools applied as an indirect measure to detect activation of the endogenous opioid system (EOS) in experimental pain models. The objective of this systematic review was to examine the effect of mu-opioid-receptor (MOR) antagonists in placebo-controlled, double-blind studies using ʻinhibitoryʼ or ʻsensitizingʼ, physiological test paradigms in healthy human subjects. The databases PubMed and Embase were searched according to predefined criteria. Out of a total of 2,142 records, 63 studies (1,477 subjects [male/female ratio = 1.5]) were considered relevant. Twenty-five studies utilized ʻinhibitoryʼ test paradigms (ITP) and 38 studies utilized ʻsensitizingʼ test paradigms (STP). The ITP-studies were characterized as conditioning modulation models (22 studies) and repetitive transcranial magnetic stimulation models (rTMS; 3 studies), and, the STP-studies as secondary hyperalgesia models (6 studies), ʻpainʼ models (25 studies), summation models (2 studies), nociceptive reflex models (3 studies) and miscellaneous models (2 studies). A consistent reversal of analgesia by a MOR-antagonist was demonstrated in 10 of the 25 ITP-studies, including stress-induced analgesia and rTMS. In the remaining 14 conditioning modulation studies either absence of effects or ambiguous effects by MOR-antagonists, were observed. In the STP-studies, no effect of the opioid-blockade could be demonstrated in 5 out of 6 secondary hyperalgesia studies. The direction of MOR-antagonist dependent effects upon pain ratings, threshold assessments and somatosensory evoked potentials (SSEP), did not appear consistent in 28 out of 32 ʻpainʼ model studies. In conclusion, only in 2 experimental human pain models, i.e., stress-induced analgesia and rTMS, administration of MOR-antagonist demonstrated a consistent effect, presumably mediated by an EOS-dependent mechanisms of analgesia and hyperalgesia. PMID:26029906

  16. Indirect Acquisition of Pain-Related Fear: An Experimental Study of Observational Learning Using Coloured Cold Metal Bars

    PubMed Central

    Helsen, Kim; Vlaeyen, Johan W. S.; Goubert, Liesbet

    2015-01-01

    Background Previous research has demonstrated that pain-related fear can be acquired through observation of another’s pain behaviour during an encounter with a painful stimulus. The results of two experimental studies were presented, each with a different pain stimulus, of which the aim was to investigate the effect of observational learning on pain expectancies, avoidance behaviour, and physiological responding. Additionally, the study investigated whether certain individuals are at heightened risk to develop pain-related fear through observation. Finally, changes in pain-related fear and pain intensity after exposure to the feared stimulus were examined. Methods During observational acquisition, healthy female participants watched a video showing coloured cold metal bars being placed against the neck of several models. In a differential fear conditioning paradigm, one colour was paired with painful facial expressions, and another colour was paired with neutral facial expressions of the video models. During exposure, both metal bars with equal temperatures (-25° or +8° Celsius) were placed repeatedly against participants’ own neck. Results Results showed that pain-related beliefs can be acquired by observing pain in others, but do not necessarily cause behavioural changes. Additionally, dispositional empathy might play a role in the acquisition of these beliefs. Furthermore, skin conductance responses were higher when exposed to the pain-associated bar, but only in one of two experiments. Differential pain-related beliefs rapidly disappeared after first-hand exposure to the stimuli. Conclusions This study enhances our understanding of pain-related fear acquisition and subsequent exposure to the feared stimulus, providing leads for pain prevention and management strategies. PMID:25806969

  17. Manipulating the Placebo Response in Experimental Pain by Altering Doctor’s Performance Style

    PubMed Central

    Czerniak, Efrat; Biegon, Anat; Ziv, Amitai; Karnieli-Miller, Orit; Weiser, Mark; Alon, Uri; Citron, Atay

    2016-01-01

    Background: Performance is paramount in traditional healing rituals. From a Western perspective, such performative behavior can be understood principally as inducing patients’ faith in the performer’s supernatural healing powers and effecting positive changes through the same mechanisms attributed to the placebo response, which is defined as improvement of clinical outcome in individuals receiving inactive treatment. Here we examined the possibility of using theatrical performance tools, including stage directions and scripting, to reproducibly manipulate the style and content of a simulated doctor–patient encounter and influence the placebo response in experimental pain. Methods: A total of 122 healthy volunteers (18–45 years, 76 men) exposed to experimental pain (the cold pressor test) were assessed for pain threshold and tolerance before and after receiving a placebo cream from a “doctor” impersonated by a trained actor. The actor alternated between two distinct scripts and stage directions, i.e., performance styles created by a theater director/playwright, one emulating a standard doctor–patient encounter (scenario A) and the other emphasizing attentiveness and strong suggestion, elements also present in ritual healing (scenario B). The placebo response size was calculated as the %difference in pain threshold and tolerance after exposure relative to baseline. In addition, subjects demonstrating a ≥30% increase in pain threshold or tolerance relative to baseline were defined as responders. Each encounter was videotaped in its entirety. Results: Inspection of the videotapes confirmed the reproducibility and consistency of the distinct scenarios enacted by the “doctor”-performer. Furthermore, scenario B resulted in a significant increase in pain threshold relative to scenario A. Interestingly, this increase derived from the placebo responder subgroup; as shown by two-way analysis of variance (performance style, F = 4.30; p = 0.040; η2 = 0

  18. A multimodal parallel architecture: A cognitive framework for multimodal interactions.

    PubMed

    Cohn, Neil

    2016-01-01

    Human communication is naturally multimodal, and substantial focus has examined the semantic correspondences in speech-gesture and text-image relationships. However, visual narratives, like those in comics, provide an interesting challenge to multimodal communication because the words and/or images can guide the overall meaning, and both modalities can appear in complicated "grammatical" sequences: sentences use a syntactic structure and sequential images use a narrative structure. These dual structures create complexity beyond those typically addressed by theories of multimodality where only a single form uses combinatorial structure, and also poses challenges for models of the linguistic system that focus on single modalities. This paper outlines a broad theoretical framework for multimodal interactions by expanding on Jackendoff's (2002) parallel architecture for language. Multimodal interactions are characterized in terms of their component cognitive structures: whether a particular modality (verbal, bodily, visual) is present, whether it uses a grammatical structure (syntax, narrative), and whether it "dominates" the semantics of the overall expression. Altogether, this approach integrates multimodal interactions into an existing framework of language and cognition, and characterizes interactions between varying complexity in the verbal, bodily, and graphic domains. The resulting theoretical model presents an expanded consideration of the boundaries of the "linguistic" system and its involvement in multimodal interactions, with a framework that can benefit research on corpus analyses, experimentation, and the educational benefits of multimodality.

  19. A multimodal parallel architecture: A cognitive framework for multimodal interactions.

    PubMed

    Cohn, Neil

    2016-01-01

    Human communication is naturally multimodal, and substantial focus has examined the semantic correspondences in speech-gesture and text-image relationships. However, visual narratives, like those in comics, provide an interesting challenge to multimodal communication because the words and/or images can guide the overall meaning, and both modalities can appear in complicated "grammatical" sequences: sentences use a syntactic structure and sequential images use a narrative structure. These dual structures create complexity beyond those typically addressed by theories of multimodality where only a single form uses combinatorial structure, and also poses challenges for models of the linguistic system that focus on single modalities. This paper outlines a broad theoretical framework for multimodal interactions by expanding on Jackendoff's (2002) parallel architecture for language. Multimodal interactions are characterized in terms of their component cognitive structures: whether a particular modality (verbal, bodily, visual) is present, whether it uses a grammatical structure (syntax, narrative), and whether it "dominates" the semantics of the overall expression. Altogether, this approach integrates multimodal interactions into an existing framework of language and cognition, and characterizes interactions between varying complexity in the verbal, bodily, and graphic domains. The resulting theoretical model presents an expanded consideration of the boundaries of the "linguistic" system and its involvement in multimodal interactions, with a framework that can benefit research on corpus analyses, experimentation, and the educational benefits of multimodality. PMID:26491835

  20. Concept priming and pain: an experimental approach to understanding gender roles in sex-related pain differences.

    PubMed

    Fowler, Stephanie L; Rasinski, Heather M; Geers, Andrew L; Helfer, Suzanne G; France, Christopher R

    2011-04-01

    Prior research has found that sex differences in pain are partially due to individual variations in gender roles. In a laboratory study, we tested the hypothesis that the presence of covert gender role cues can also moderate the extent to which women and men experience pain. Specifically, we varied gender role cues by asking male and female participants to write about instances in which they behaved in a stereotypically feminine, masculine, or neutral manner. Pain and cardiovascular reactivity to the cold pressor task were then assessed. Results revealed that, when primed with femininity, men reported less pain and anxiety from the cold pressor task than women. However, no differences existed between the sexes in the masculine or neutral prime conditions. The results indicate that covert gender cues can alter pain reports. Further, at least in some situations, feminine role cues may be more influential on pain reports than masculine role cues.

  1. Pharmacodynamic modelling of placebo and buprenorphine effects on event-related potentials in experimental pain.

    PubMed

    Juul, Rasmus V; Foster, David J R; Upton, Richard N; Andresen, Trine; Graversen, Carina; Drewes, Asbjørn M; Christrup, Lona L; Kreilgaard, Mads

    2014-10-01

    The purpose of the study was to investigate placebo and buprenorphine effects on event-related potentials (ERPs) in experimental pain and the potential benefit of population pharmacodynamic modelling in data analysis. Nineteen healthy volunteers received transdermal placebo and buprenorphine in a cross-over study. Drug plasma concentrations and ERPs after electrical stimulation at the median nerve with intensity adjusted to pain detection threshold were recorded until 144 hrs after administration. Placebo and concentration-effect models were fitted to data using non-linear mixed-effects modelling implemented in NONMEM (V7.2.0.). Pharmacodynamic models were developed to adequately describe both placebo and buprenorphine ERP data. Models predicted significant placebo effects, but did not predict significant effects related to buprenorphine concentration. Models revealed that ERPs varied both between subjects and between study occasions. ERPs were found to be reproducible within subjects and occasions as population variance was found to be eight times higher than the unexplained variances. Between-subject variance accounted for more than 75% of the population variance. In conclusion, pharmacodynamic modelling was successfully implemented to allow for placebo and variability correction in ERP of experimental pain. Improved outcome of ERP studies can be expected if variation between subjects and study occasions can be identified and described.

  2. Voluntary wheel running delays disease onset and reduces pain hypersensitivity in early experimental autoimmune encephalomyelitis (EAE).

    PubMed

    Benson, Curtis; Paylor, John W; Tenorio, Gustavo; Winship, Ian; Baker, Glen; Kerr, Bradley J

    2015-09-01

    Multiple sclerosis (MS) is classically defined by motor deficits, but it is also associated with the secondary symptoms of pain, depression, and anxiety. Up to this point modifying these secondary symptoms has been difficult. There is evidence that both MS and the animal model experimental autoimmune encephalomyelitis (EAE), commonly used to study the pathophysiology of the disease, can be modulated by exercise. To examine whether limited voluntary wheel running could modulate EAE disease progression and the co-morbid symptoms of pain, mice with EAE were allowed access to running wheels for 1h every day. Allowing only 1h every day of voluntary running led to a significant delay in the onset of clinical signs of the disease. The development of mechanical allodynia was assessed using Von Frey hairs and indicated that wheel running had a modest positive effect on the pain hypersensitivity associated with EAE. These behavioral changes were associated with reduced numbers of cFOS and phosphorylated NR1 positive cells in the dorsal horn of the spinal cord compared to no-run EAE controls. In addition, within the dorsal horn, voluntary wheel running reduced the number of infiltrating CD3(+) T-cells and reduced the overall levels of Iba1 immunoreactivity. Using high performance liquid chromatography (HPLC), we observed that wheel-running lead to significant changes in the spinal cord levels of the antioxidant glutathione. Oxidative stress has separately been shown to contribute to EAE disease progression and neuropathic pain. Together these results indicate that in mice with EAE, voluntary motor activity can delay the onset of clinical signs and reduce pain symptoms associated with the disease. PMID:26033473

  3. Voluntary wheel running delays disease onset and reduces pain hypersensitivity in early experimental autoimmune encephalomyelitis (EAE).

    PubMed

    Benson, Curtis; Paylor, John W; Tenorio, Gustavo; Winship, Ian; Baker, Glen; Kerr, Bradley J

    2015-09-01

    Multiple sclerosis (MS) is classically defined by motor deficits, but it is also associated with the secondary symptoms of pain, depression, and anxiety. Up to this point modifying these secondary symptoms has been difficult. There is evidence that both MS and the animal model experimental autoimmune encephalomyelitis (EAE), commonly used to study the pathophysiology of the disease, can be modulated by exercise. To examine whether limited voluntary wheel running could modulate EAE disease progression and the co-morbid symptoms of pain, mice with EAE were allowed access to running wheels for 1h every day. Allowing only 1h every day of voluntary running led to a significant delay in the onset of clinical signs of the disease. The development of mechanical allodynia was assessed using Von Frey hairs and indicated that wheel running had a modest positive effect on the pain hypersensitivity associated with EAE. These behavioral changes were associated with reduced numbers of cFOS and phosphorylated NR1 positive cells in the dorsal horn of the spinal cord compared to no-run EAE controls. In addition, within the dorsal horn, voluntary wheel running reduced the number of infiltrating CD3(+) T-cells and reduced the overall levels of Iba1 immunoreactivity. Using high performance liquid chromatography (HPLC), we observed that wheel-running lead to significant changes in the spinal cord levels of the antioxidant glutathione. Oxidative stress has separately been shown to contribute to EAE disease progression and neuropathic pain. Together these results indicate that in mice with EAE, voluntary motor activity can delay the onset of clinical signs and reduce pain symptoms associated with the disease.

  4. Isolated and combined effects of electroacupuncture and meditation in reducing experimentally induced ischemic pain: a pilot study.

    PubMed

    Choi, Kyung-Eun; Musial, Frauke; Amthor, Nadine; Rampp, Thomas; Saha, Felix J; Michalsen, Andreas; Dobos, Gustav J

    2011-01-01

    Acupuncture and meditation are promising treatment options for clinical pain. However, studies investigating the effects of these methods on experimental pain conditions are equivocal. Here, the effects of electroacupuncture (EA) and meditation on the submaximum effort tourniquet technique (SETT), a well-established, opiate-sensitive pain paradigm in experimental placebo research were studied. Ten experienced meditators (6 male subjects) and 13 nonmeditators (6 male subjects) were subjected to SETT (250 mmHG) on one baseline (SETT only) and two treatment days (additional EA contralaterally to the SETT, either at the leg on ST36 and LV3 or at the arm on LI4 and LI10 in randomized order). Numeric Rating Scale (NRS) ratings (scale 0-10) were recorded every 3 min. During baseline, meditation induced significantly greater pain tolerance in meditators when compared with the control group. Both the EA conditions significantly increased pain tolerance and reduced pain ratings in controls. Furthermore, EA diminished the group difference in pain sensitivity, indicating that meditators had no additional benefit from acupuncture. The data suggest that EA as a presumable bottom-up process may be as effective as meditation in controlling experimental SETT pain. However, no combined effect of both the techniques could be observed.

  5. Inter-individual responses to experimental muscle pain: Baseline anxiety ratings and attitudes to pain do not determine the direction of the sympathetic response to tonic muscle pain in humans.

    PubMed

    Kobuch, Sophie; Fazalbhoy, Azharuddin; Brown, Rachael; Macefield, Vaughan G

    2016-06-01

    We have recently shown that intramuscular infusion of hypertonic saline, causing pain lasting ~60min, increases muscle sympathetic nerve activity (MSNA) in one group of subjects, yet decreases it in another. Across subjects these divergent sympathetic responses to long-lasting muscle pain are consistent over time and cannot be foreseen on the basis of baseline MSNA, blood pressure, heart rate or sex. We predicted that differences in anxiety or attitudes to pain may account for these differences. Psychometric measures were assessed prior to the induction of pain using the State and Trait Anxiety Inventory (STAI), Pain Vigilance and Awareness Questionnaire (PVAQ), Pain Anxiety Symptoms Scale (PASS) and Pain Catastrophising Scale (PCS); PCS was also administered after the experiment. MSNA was recorded from the common peroneal nerve, before and during a 45-minute intramuscular infusion of hypertonic saline solution into the tibialis anterior muscle of 66 awake human subjects. Forty-one subjects showed an increase in mean burst amplitude of MSNA (172.8±10.6%) while 25 showed a decrease (69.9±3.8%). None of the measured psychological parameters showed significant differences between the increasing and the decreasing groups. We conclude that inter-individual anxiety or pain attitudes do not determine whether MSNA increases or decreases during long-lasting experimental muscle pain in healthy human subjects. PMID:27106401

  6. Effect of endocannabinoid degradation on pain: role of FAAH polymorphisms in experimental and postoperative pain in women treated for breast cancer.

    PubMed

    Cajanus, Kristiina; Holmström, Emil J; Wessman, Maija; Anttila, Verneri; Kaunisto, Mari A; Kalso, Eija

    2016-02-01

    Fatty acid amide hydrolase (FAAH) metabolizes the endocannabinoid anandamide, which has an important role in nociception. We investigated the role of common FAAH single-nucleotide polymorphisms (SNPs) in experimentally induced and postoperative pain. One thousand women undergoing surgery for breast cancer participated in the study. They were tested for cold (n = 900) and heat pain (n = 1000) sensitivity. After surgery, their pain intensities and analgesic consumption were carefully registered. FAAH genotyping was performed using MassARRAY platform and genome-wide chip (n = 926). Association between 8 FAAH SNPs and 9 pain phenotypes was analyzed using linear regression models. The results showed that carrying 2 copies of a missense variant converting proline at position 129 to threonine (rs324420) resulted in significantly lower cold pain sensitivity and less need for postoperative analgesia. More specifically, rs324420 and another highly correlated SNP, rs1571138, associated significantly with cold pain intensity (corrected P value, 0.0014; recessive model). Patients homozygous for the minor allele (AA genotype) were less sensitive to cold pain (β = -1.48; 95% CI, -2.14 to -0.8). Two other SNPs (rs3766246 and rs4660928) showed nominal association with cold pain, and SNPs rs4141964, rs3766246, rs324420, and rs1571138 nominal association with oxycodone consumption. In conclusion, FAAH gene variation was shown to associate with cold pain sensitivity with P129T/rs324420 being the most likely causal variant as it is known to reduce the FAAH enzyme activity. The same variant showed nominal association with postoperative oxycodone consumption. Our conclusions are, however, limited by the lack of replication and the results should be replicated in an independent cohort.

  7. IL-17 is not essential for inflammation and chronic pelvic pain development in an experimental model of chronic prostatitis/chronic pelvic pain syndrome.

    PubMed

    Motrich, Ruben D; Breser, María L; Sánchez, Leonardo R; Godoy, Gloria J; Prinz, Immo; Rivero, Virginia E

    2016-03-01

    Pain and inflammation in the absence of infection are hallmarks in chronic prostatitis and chronic pelvic pain syndrome (CP/CPPS) patients. The etiology of CP/CPPS is unclear, and autoimmunity has been proposed as a cause. Experimental autoimmune prostatitis (EAP) models have long been used for studying CP/CPPS. Herein, we studied prostate inflammation induction and chronic pelvic pain development in EAP using IL-12p40-KO, IL-4-KO, IL-17-KO, and wild-type (C57BL/6) mice. Prostate antigen (PAg) immunization in C57BL/6 mice induced specific Th1 and Th17 immune responses and severe prostate inflammation and cell infiltration, mainly composed of CD4 T cells and macrophages. Moreover, chronic pelvic pain was evidenced by increased allodynia responses. In immunized IL-17-KO mice, the presence of a prominent PAg-specific Th1 immune response caused similar prostate inflammation and chronic pelvic pain. Furthermore, markedly high PAg-specific Th1 immune responses, exacerbated prostate inflammation, and chronic pelvic pain were detected in immunized IL-4-KO mice. Conversely, immunized IL-12p40-KO mice developed PAg-specific Th2 immune responses, characterized by high IL-4 secretion and neither infiltration nor damage in the prostate. As observed in wild-type control animals, IL12p40-KO mice did not evidence tactile allodynia responses. Our results suggest that, as in patients, chronic pelvic pain is a consequence of prostate inflammation. After PAg immunization, a Th1-associated immune response develops and induces prostate inflammation and chronic pelvic pain. The absence of Th1 or Th2 cytokines, respectively, diminishes or enhances EAP susceptibility. In addition, IL-17 showed not to be essential for pathology induction and chronic pelvic pain development.

  8. A Learning Algorithm for Multimodal Grammar Inference.

    PubMed

    D'Ulizia, A; Ferri, F; Grifoni, P

    2011-12-01

    The high costs of development and maintenance of multimodal grammars in integrating and understanding input in multimodal interfaces lead to the investigation of novel algorithmic solutions in automating grammar generation and in updating processes. Many algorithms for context-free grammar inference have been developed in the natural language processing literature. An extension of these algorithms toward the inference of multimodal grammars is necessary for multimodal input processing. In this paper, we propose a novel grammar inference mechanism that allows us to learn a multimodal grammar from its positive samples of multimodal sentences. The algorithm first generates the multimodal grammar that is able to parse the positive samples of sentences and, afterward, makes use of two learning operators and the minimum description length metrics in improving the grammar description and in avoiding the over-generalization problem. The experimental results highlight the acceptable performances of the algorithm proposed in this paper since it has a very high probability of parsing valid sentences.

  9. The effect of experimental pain on motor training performance and sensorimotor integration.

    PubMed

    Dancey, Erin; Murphy, Bernadette; Srbely, John; Yielder, Paul

    2014-09-01

    Experimental pain is known to affect neuroplasticity of the motor cortex as well as motor performance, but less is known about neuroplasticity of somatosensory processing in the presence of pain. Early somatosensory evoked potentials (SEPs) provide a mechanism for investigating alterations in sensory processing and sensorimotor integration (SMI). The overall aim of this study was to investigate the interactive effects of acute pain, motor training, and sensorimotor processing. Two groups of twelve participants (N = 24) were randomly assigned to either an intervention (capsaicin cream) or placebo (inert lotion) group. SEP amplitudes were collected by stimulation of the median nerve at baseline, post-application and post-motor training. Participants performed a motor sequence task while reaction time and accuracy data were recorded. The amplitude of the P22-N24 complex was significantly increased following motor training for both groups F(2,23) = 3.533, p < 0.05, while Friedman's test for the P22-N30 complex showed a significant increase in the intervention group [χ(2) (df = 2, p = 0.016) = 8.2], with no significant change in the placebo group. Following motor training, reaction time was significantly decreased for both groups F(1,23) = 59.575, p < 0.01 and overall accuracy differed by group [χ(2) (df = 3, p < 0.001) = 19.86], with post hoc testing indicating that the intervention group improved in accuracy following motor training [χ(2) (df = 1, p = 0.001) = 11.77] while the placebo group had worse accuracy [χ(2) (df = 1, p = 0.006) = 7.67]. The improved performance in the presence of capsaicin provides support for the enhancement of knowledge acquisition with the presence of nontarget stimuli. In addition, the increase in SEP peak amplitudes suggests that early SEP changes are markers of SMI changes accompanying motor training and acute pain.

  10. Can personality traits and gender predict the response to morphine? An experimental cold pain study.

    PubMed

    Pud, Dorit; Yarnitsky, David; Sprecher, Elliot; Rogowski, Zeev; Adler, Rivka; Eisenberg, Elon

    2006-02-01

    The aim of the present study was to examine the possible role of personality traits, in accordance with Cloninger's theory, and gender, in the variability of responsiveness to opioids. Specifically, it was intended to test whether or not the three personality dimensions - harm avoidance (HA), reward dependence (RD) and novelty seeking (NS) - as suggested by Cloninger, can predict inter-personal differences in responsiveness to morphine after exposure to experimental cold pain. Thirty-four healthy volunteers (15 females, 19 males) were given the cold pressor test (CPT). Pain threshold, tolerance, and magnitude (VAS) were measured before and after (six measures, 30 min apart) the administration of either 0.5 mg/kg oral morphine sulphate (n=21) or 0.33 mg/kg oral active placebo (diphenhydramine) (n=13) in a randomized, double blind design. Assessment of the three personality traits, according to Cloninger's Tridimensional Personality Questionnaire, was performed before the CPT. A high HA score (but not RD, NS, or baseline values of the three pain parameters) predicted a significantly larger pain relief following the administration of morphine sulphate (but not of the placebo). Women exhibited a larger response in response to both treatments, as indicated by a significantly increased threshold and tolerance following morphine sulphate as well as significantly increased tolerance and decreased magnitude following placebo administration. The present study confirms the existence of individual differences in response to analgesic treatment. It suggests that high HA personality trait is associated with better responsiveness to morphine treatment, and that females respond better than men to both morphine and placebo.

  11. Multimodal Therapy.

    ERIC Educational Resources Information Center

    Lazarus, Arnold A.

    The multimodal therapy (MMT) approach provides a framework that facilitates systematic treatment selection in a broad-based, comprehensive and yet highly focused manner. It respects science, and data driven findings, and endeavors to use empirically supported methods when possible. Nevertheless, it recognizes that many issues still fall into the…

  12. Experimental Pain and Opioid Analgesia in Volunteers at High Risk for Obstructive Sleep Apnea

    PubMed Central

    Doufas, Anthony G.; Tian, Lu; Padrez, Kevin A.; Suwanprathes, Puntarica; Cardell, James A.; Maecker, Holden T.; Panousis, Periklis

    2013-01-01

    Background Obstructive sleep apnea (OSA) is characterized by recurrent nocturnal hypoxia and sleep disruption. Sleep fragmentation caused hyperalgesia in volunteers, while nocturnal hypoxemia enhanced morphine analgesic potency in children with OSA. This evidence directly relates to surgical OSA patients who are at risk for airway compromise due to postoperative use of opioids. Using accepted experimental pain models, we characterized pain processing and opioid analgesia in male volunteers recruited based on their risk for OSA. Methods After approval from the Intitutional Review Board and informed consent, we assessed heat and cold pain thresholds and tolerances in volunteers after overnight polysomnography (PSG). Three pro-inflammatory and 3 hypoxia markers were determined in the serum. Pain tests were performed at baseline, placebo, and two effect site concentrations of remifentanil (1 and 2 µg/ml), an μ-opioid agonist. Linear mixed effects regression models were employed to evaluate the association of 3 PSG descriptors [wake after sleep onset, number of sleep stage shifts, and lowest oxyhemoglobin saturation (SaO2) during sleep] and all serum markers with pain thresholds and tolerances at baseline, as well as their changes under remifentanil. Results Forty-three volunteers (12 normal and 31 with a PSG-based diagnosis of OSA) were included in the analysis. The lower nadir SaO2 and higher insulin growth factor binding protein-1 (IGFBP-1) were associated with higher analgesic sensitivity to remifentanil (SaO2, P = 0.0440; IGFBP-1, P = 0.0013). Other pro-inflammatory mediators like interleukin-1β and tumor necrosis factor-α (TNF-α) were associated with an enhanced sensitivity to the opioid analgesic effect (IL-1β, P = 0.0218; TNF-α, P = 0.0276). Conclusions Nocturnal hypoxemia in subjects at high risk for OSA was associated with an increased potency of opioid analgesia. A serum hypoxia marker (IGFBP-1) was associated with hypoalgesia and

  13. Center of Pressure Displacement of Standing Posture during Rapid Movements Is Reorganised Due to Experimental Lower Extremity Muscle Pain

    PubMed Central

    Shiozawa, Shinichiro; Hirata, Rogerio Pessoto; Graven-Nielsen, Thomas

    2015-01-01

    Background Postural control during rapid movements may be impaired due to musculoskeletal pain. The purpose of this study was to investigate the effect of experimental knee-related muscle pain on the center of pressure (CoP) displacement in a reaction time task condition. Methods Nine healthy males performed two reaction time tasks (dominant side shoulder flexion and bilateral heel lift) before, during, and after experimental pain induced in the dominant side vastus medialis or the tibialis anterior muscles by hypertonic saline injections. The CoP displacement was extracted from the ipsilateral and contralateral side by two force plates and the net CoP displacement was calculated. Results Compared with non-painful sessions, tibialis anterior muscle pain during the peak and peak-to-peak displacement for the CoP during anticipatory postural adjustments (APAs) of the shoulder task reduced the peak-to-peak displacement of the net CoP in the medial-lateral direction (P<0.05). Tibialis anterior and vastus medialis muscle pain during shoulder flexion task reduced the anterior-posterior peak-to-peak displacement in the ipsilateral side (P<0.05). Conclusions The central nervous system in healthy individuals was sufficiently robust in maintaining the APA characteristics during pain, although the displacement of net and ipsilateral CoP in the medial-lateral and anterior-posterior directions during unilateral fast shoulder movement was altered. PMID:26680777

  14. Effects of a Hypnotic Induction and an Unpleasantness-Focused Analgesia Suggestion on Pain Catastrophizing to an Experimental Heat Stimulus: A Preliminary Study.

    PubMed

    Adachi, Tomonori; Nakae, Aya; Sasaki, Jun

    2016-01-01

    Pain catastrophizing is associated with greater levels of pain. While many studies support the efficacy of hypnosis for pain, the effect on pain catastrophizing remains unclear. The present study evaluated the effect of hypnosis on pain catastrophizing using experimental heat stimulation. Twenty-two pain patients engaged in 3 conditions: baseline (no suggestion), hypnotic induction, and hypnotic induction plus analgesia suggestion. Participants with higher baseline pain showed a significant reduction in rumination following hypnotic induction plus analgesia suggestion and significant reductions in pain due to both the hypnotic induction alone and the hypnotic induction plus analgesia suggestion. The findings suggest that unpleasantness-focused hypnotic analgesia reduces pain via its effect on the rumination component of pain catastrophizing. PMID:27585727

  15. The Effects of Experimentally Induced Low Back Pain on Spine Rotational Stiffness and Local Dynamic Stability.

    PubMed

    Ross, Gwyneth B; Mavor, Matthew; Brown, Stephen H M; Graham, Ryan B

    2015-09-01

    Local dynamic stability, quantified using the maximum finite-time Lyapunov exponent (λ max), and the muscular contributions to spine rotational stiffness can provide pertinent information regarding the neuromuscular control of the spine during movement tasks. The primary goal of the present study was to assess if experimental capsaicin-induced low back pain (LBP) affects spine stability and the neuromuscular control of repetitive trunk movements in a group of healthy participants with no history of LBP. Fourteen healthy males were recruited for this investigation. Each participant was asked to complete three trials (baseline, in pain, and recovery) of 35 cycles of a repetitive trunk flexion/extension task at a rate of 0.25 Hz. Local dynamic stability and the muscular contributions to lumbar spine rotational stiffness were significantly impaired during the LBP trial compared to the baseline trial (p < 0.05); however, there was a trend for these measures to recover after a 1 h rest. This study provides evidence that capsaicin can effectively induce LBP, thereby altering spine rotational stiffness and local dynamic stability. Future research should directly compare the effects capsaicin-induced LBP and intramuscular/intraligamentous induced LBP on these same variables.

  16. Effects of experimentally induced low back pain on the sit-to-stand movement and electroencephalographic contingent negative variation.

    PubMed

    Jacobs, Jesse V; Yaguchi, Chie; Kaida, Chizuru; Irei, Mariko; Naka, Masami; Henry, Sharon M; Fujiwara, Katsuo

    2011-11-01

    It is becoming increasingly evident that people with chronic, recurrent low back pain (LBP) exhibit changes in cerebrocortical activity that associate with altered postural coordination, suggesting a need for a better understanding of how the experience of LBP alters postural coordination and cerebrocortical activity. To characterize changes in postural coordination and pre-movement cerebrocortical activity related to the experience of acutely induced LBP, 14 healthy participants with no history of LBP performed sit-to-stand movements in 3 sequential conditions: (1) without experimentally induced LBP; NoPain1, (2) with movement-associated LBP induced by electrocutaneous stimulation; Pain, and (3) again without induced LBP; NoPain2. The Pain condition elicited altered muscle activation and redistributed forces under the seat and feet prior to movement, decreased peak vertical force exerted under the feet during weight transfer, longer movement times, as well as decreased and earlier peak hip extension. Stepwise regression models demonstrated that electroencephalographic amplitudes of contingent negative variation during the Pain condition significantly correlated with the participants' change in sit-to-stand measures between the NoPain1 and Pain conditions, as well as with the subsequent difference in sit-to-stand measures between the NoPain1 and NoPain2 conditions. The results, therefore, identify the contingent negative variation as a correlate for the extent of an individual's LBP-related movement modifications and to the subsequent change in movement patterns from before to after the experience of acutely induced LBP, thereby providing a direction for future studies aimed to understand the neural mechanisms underlying the development of altered movement patterns with LBP.

  17. An experimental paradigm for the prediction of Post-Operative Pain (PPOP).

    PubMed

    Landau, Ruth; Kraft, John C; Flint, Lisa Y; Carvalho, Brendan; Richebé, Philippe; Cardoso, Monica; Lavand'homme, Patricia; Granot, Michal; Yarnitsky, David; Cahana, Alex

    2010-01-01

    Many women undergo cesarean delivery without problems, however some experience significant pain after cesarean section. Pain is associated with negative short-term and long-term effects on the mother. Prior to women undergoing surgery, can we predict who is at risk for developing significant postoperative pain and potentially prevent or minimize its negative consequences? These are the fundamental questions that a team from the University of Washington, Stanford University, the Catholic University in Brussels, Belgium, Santa Joana Women's Hospital in São Paulo, Brazil, and Rambam Medical Center in Israel is currently evaluating in an international research collaboration. The ultimate goal of this project is to provide optimal pain relief during and after cesarean section by offering individualized anesthetic care to women who appear to be more 'susceptible' to pain after surgery. A significant number of women experience moderate or severe acute post-partum pain after vaginal and cesarean deliveries. (1) Furthermore, 10-15% of women suffer chronic persistent pain after cesarean section. (2) With constant increase in cesarean rates in the US (3) and the already high rate in Brazil, this is bound to create a significant public health problem. When questioning women's fears and expectations from cesarean section, pain during and after it is their greatest concern. (4) Individual variability in severity of pain after vaginal or operative delivery is influenced by multiple factors including sensitivity to pain, psychological factors, age, and genetics. The unique birth experience leads to unpredictable requirements for analgesics, from 'none at all' to 'very high' doses of pain medication. Pain after cesarean section is an excellent model to study post-operative pain because it is performed on otherwise young and healthy women. Therefore, it is recommended to attenuate the pain during the acute phase because this may lead to chronic pain disorders. The impact of

  18. Independent psychophysical measurement of experimental modulations in the somatotopy of cutaneous heat-pain stimuli.

    PubMed

    Trojan, Jörg; Kleinböhl, Dieter; Stolle, Annette M; Andersen, Ole K; Hölzl, Rupert; Arendt-Nielsen, Lars

    2009-03-01

    Distortions of the body image have been repeatedly reported for various clinical conditions, but direct experimental analyses of the perceptual changes involved are still scarce. In addition, most experimental studies rely on cerebral activation patterns to assess neuroplastic changes in central representation, although the relationship between cerebral topography and the topology of the perceptual space is not clear. This study examines whether the direct psychophysical mapping approach we introduced recently (Trojan et al., Brain Res 2006;1120:106-113) is capable of tracking perceptual distortions in the somatotopic representation of heat-pain stimuli. Eleven healthy participants indicated the perceived positions of CO(2) laser stimuli, repetitively presented to the dorsal forearm, with a 3D tracking system in two consecutive sessions, separated by the topical application of capsaicin cream. In line with earlier reports, we expected that the resulting individual perceptual maps (i.e., one-dimensional projections of the perceived positions onto the forearm surface) would be subject to modulation through the altered sensory input, to be measured in terms of altered topological parameters. We found that the topology and metrics of the somatotopic representation were well preserved in the second session, but that the perceptual map was compressed to a smaller range in 9 out of 11 participants. By providing dimensional measures of perceptual representations, perceptual maps constitute an independent, genuinely psychological complement to the topography of cortical activations measured with neuroimaging methods. In addition, we expect them to be useful in diagnosing pathological changes in body perception accompanying chronic pain and other disorders.

  19. Multimodal eye recognition

    NASA Astrophysics Data System (ADS)

    Zhou, Zhi; Du, Yingzi; Thomas, N. L.; Delp, Edward J., III

    2010-04-01

    Multimodal biometrics use more than one means of biometric identification to achieve higher recognition accuracy, since sometimes a unimodal biometric is not good enough used to do identification and classification. In this paper, we proposed a multimodal eye recognition system, which can obtain both iris and sclera patterns from one color eye image. Gabor filter and 1-D Log-Gabor filter algorithms have been applied as the iris recognition algorithms. In sclera recognition, we introduced automatic sclera segmentation, sclera pattern enhancement, sclera pattern template generation, and sclera pattern matching. We applied kernelbased matching score fusion to improve the performance of the eye recognition system. The experimental results show that the proposed eye recognition method can achieve better performance compared to unimodal biometric identification, and the accuracy of our proposed kernel-based matching score fusion method is higher than two classic linear matching score fusion methods: Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA).

  20. The Effect of Oral Morphine on Pain-Related Brain Activation - An Experimental Functional Magnetic Resonance Imaging Study.

    PubMed

    Hansen, Tine Maria; Olesen, Anne Estrup; Graversen, Carina; Drewes, Asbjørn Mohr; Frøkjaer, Jens Brøndum

    2015-11-01

    Knowledge about cerebral mechanisms underlying pain perception and effect of analgesic drugs is important for developing methods for diagnosis and treatment of pain. The aim was to explore altered brain activation before and after morphine treatment using functional magnetic resonance imaging recorded during experimental painful heat stimulation. Functional magnetic resonance imaging data were recorded and analysed in 20 healthy volunteers (13 men and 7 women, 24.9 ± 2.6 years) in a randomized, double-blind, placebo-controlled, cross-over study. Painful stimulations were applied to the right forearm using a contact heat evoked potential stimulator (CHEPS) before and after treatment with 30 mg oral morphine and placebo. CHEPS stimulations before treatment induced activation in the anterior cingulate cortex, secondary somatosensory cortex/insula, thalamus and cerebellum (n = 16, p < 0.05). In response to morphine treatment, the spatial extent of these pain-specific areas decreased (n = 20). Reduced pain-induced activation was seen in the right insula, anterior cingulate cortex and inferior parietal cortex after morphine treatment compared to before treatment (n = 16, p < 0.05), and sensory ratings of pain perception were significantly reduced after morphine treatment (p = 0.02). No effect on pain-induced brain activation was seen after placebo treatment compared to before treatment (n = 12, p > 0.05). In conclusion, heat stimulation activated areas in the 'pain matrix' and a clinically relevant dose of orally administered morphine revealed significant changes in brain areas where opioidergic pathways are predominant. The method may be useful to investigate the mechanisms of analgesics.

  1. Multimodality Neuromonitoring.

    PubMed

    Kirkman, Matthew A; Smith, Martin

    2016-09-01

    The monitoring of systemic and central nervous system physiology is central to the management of patients with neurologic disease in the perioperative and critical care settings. There exists a range of invasive and noninvasive and global and regional monitors of cerebral hemodynamics, oxygenation, metabolism, and electrophysiology that can be used to guide treatment decisions after acute brain injury. With mounting evidence that a single neuromonitor cannot comprehensively detect all instances of cerebral compromise, multimodal neuromonitoring allows an individualized approach to patient management based on monitored physiologic variables rather than a generic one-size-fits-all approach targeting predetermined and often empirical thresholds. PMID:27521195

  2. Effectiveness of Self-Hypnosis on the Relief of Experimental Dental Pain: A Randomized Trial.

    PubMed

    Wolf, Thomas Gerhard; Wolf, Dominik; Below, Dagna; d'Hoedt, Bernd; Willershausen, Brita; Daubländer, Monika

    2016-01-01

    This randomized, controlled clinical trial evaluates the effectiveness of self-hypnosis on pain perception. Pain thresholds were measured, and a targeted, standardized pain stimulus was created by electrical stimulation of the dental pulp of an upper anterior tooth. Pain stimulus was rated by a visual analogue scale (VAS). The pain threshold under self-hypnosis was higher (57.1 ± 17.1) than without hypnotic intervention (39.5 ± 11.8) (p < .001). Pain was rated lower on the VAS with self-hypnosis (4.0 ± 3.8) than in the basal condition without self-hypnosis (7.1 ± 2.7) (p < .001). Self-hypnosis can be used in clinical practice as an adjunct to the gold standard of local anesthesia for pain management, as well as an alternative in individual cases. PMID:26894422

  3. Reduced habituation to experimental pain in migraine patients: a CO(2) laser evoked potential study.

    PubMed

    Valeriani, M; de Tommaso, M; Restuccia, D; Le Pera, D; Guido, M; Iannetti, G D; Libro, G; Truini, A; Di Trapani, G; Puca, F; Tonali, P; Cruccu, G

    2003-09-01

    The habituation to sensory stimuli of different modalities is reduced in migraine patients. However, the habituation to pain has never been evaluated. Our aim was to assess the nociceptive pathway function and the habituation to experimental pain in patients with migraine. Scalp potentials were evoked by CO(2) laser stimulation (laser evoked potentials, LEPs) of the hand and facial skin in 24 patients with migraine without aura (MO), 19 patients with chronic tension-type headache (CTTH), and 28 control subjects (CS). The habituation was studied by measuring the changes of LEP amplitudes across three consecutive repetitions of 30 trials each (the repetitions lasted 5 min and were separated by 5-min intervals). The slope of the regression line between LEP amplitude and number of repetitions was taken as an index of habituation. The LEPs consisted of middle-latency, low-amplitude responses (N1, contralateral temporal region, and P1, frontal region) followed by a late, high-amplitude, negative-positive complex (N2/P2, vertex). The latency and amplitude of these responses were similar in both patients and controls. While CS and CTTH patients showed a significant habituation of the N2/P2 response, in MO patients this LEP component did not develop any habituation at all after face stimulation and showed a significantly lower habituation than in CS after hand stimulation. The habituation index of the vertex N2/P2 complex exceeded the normal limits in 13 out of the 24 MO patients and in none of the 19 CTTH patients (P<0.0001; Fisher's exact test). Moreover, while the N1-P1 amplitude showed a significant habituation in CS after hand stimulation, it did not change across repetitions in MO patients. In conclusion, no functional impairment of the nociceptive pathways, including the trigeminal pathways, was found in either MO or CTTH patients. But patients with migraine had a reduced habituation, which probably reflects an abnormal excitability of the cortical areas involved in

  4. Reduced habituation to experimental pain in migraine patients: a CO(2) laser evoked potential study.

    PubMed

    Valeriani, M; de Tommaso, M; Restuccia, D; Le Pera, D; Guido, M; Iannetti, G D; Libro, G; Truini, A; Di Trapani, G; Puca, F; Tonali, P; Cruccu, G

    2003-09-01

    The habituation to sensory stimuli of different modalities is reduced in migraine patients. However, the habituation to pain has never been evaluated. Our aim was to assess the nociceptive pathway function and the habituation to experimental pain in patients with migraine. Scalp potentials were evoked by CO(2) laser stimulation (laser evoked potentials, LEPs) of the hand and facial skin in 24 patients with migraine without aura (MO), 19 patients with chronic tension-type headache (CTTH), and 28 control subjects (CS). The habituation was studied by measuring the changes of LEP amplitudes across three consecutive repetitions of 30 trials each (the repetitions lasted 5 min and were separated by 5-min intervals). The slope of the regression line between LEP amplitude and number of repetitions was taken as an index of habituation. The LEPs consisted of middle-latency, low-amplitude responses (N1, contralateral temporal region, and P1, frontal region) followed by a late, high-amplitude, negative-positive complex (N2/P2, vertex). The latency and amplitude of these responses were similar in both patients and controls. While CS and CTTH patients showed a significant habituation of the N2/P2 response, in MO patients this LEP component did not develop any habituation at all after face stimulation and showed a significantly lower habituation than in CS after hand stimulation. The habituation index of the vertex N2/P2 complex exceeded the normal limits in 13 out of the 24 MO patients and in none of the 19 CTTH patients (P<0.0001; Fisher's exact test). Moreover, while the N1-P1 amplitude showed a significant habituation in CS after hand stimulation, it did not change across repetitions in MO patients. In conclusion, no functional impairment of the nociceptive pathways, including the trigeminal pathways, was found in either MO or CTTH patients. But patients with migraine had a reduced habituation, which probably reflects an abnormal excitability of the cortical areas involved in

  5. Chenopodium ambrosioides L. Reduces Synovial Inflammation and Pain in Experimental Osteoarthritis

    PubMed Central

    Calado, Gustavo P.; Lopes, Alberto Jorge O.; Costa Junior, Livio M.; Lima, Francisco das Chagas A.; Silva, Lucilene A.; Pereira, Wanderson S.; do Amaral, Flávia M. M.; Garcia, João Batista S.; Cartágenes, Maria do Socorro de S.; Nascimento, Flávia R. F.

    2015-01-01

    The chronicity of osteoarthritis (OA), characterized by pain and inflammation in the joints, is linked to a glutamate receptor, N-methyl-D-aspartate (NMDA). The use of plant species such as Chenopodium ambrosioides L. (Amaranthaceae) as NMDA antagonists offers a promising perspective. This work aims to analyze the antinociceptive and anti-inflammatory responses of the crude hydroalcoholic extract (HCE) of C. ambrosioides leaves in an experimental OA model. Wistar rats were separated into six groups (n = 24): clean (C), negative control (CTL-), positive control (CTL+), HCE0.5, HCE5 and HCE50. The first group received no intervention. The other groups received an intra-articular injection of sodium monoiodoacetate (MIA) (8 mg/kg) on day 0. After six hours, they were orally treated with saline, Maxicam plus (meloxicam + chondroitin sulfate) and HCE at doses of 0.5 mg/kg, 5 mg/kg and 50 mg/kg, respectively. After three, seven and ten days, clinical evaluations were performed (knee diameter, mechanical allodynia, mechanical hyperalgesia and motor activity). On the tenth day, after euthanasia, synovial fluid and draining lymph node were collected for cellular quantification, and cartilage was collected for histopathological analysis. Finally, molecular docking was performed to evaluate the compatibility of ascaridole, a monoterpene found in HCE, with the NMDA receptor. After the third day, HCE reduced knee edema. HCE5 showed less cellular infiltrate in the cartilage and synovium and lower intensities of allodynia from the third day and of hyperalgesia from the seventh day up to the last treatment day. The HCE5 and HCE50 groups improved in forced walking. In relation to molecular docking, ascaridole showed NMDA receptor binding affinity. C. ambrosioides HCE was effective in the treatment of OA because it reduced synovial inflammation and behavioral changes due to pain. This effect may be related to the antagonistic effect of ascaridole on the NMDA receptor. PMID:26524084

  6. Chenopodium ambrosioides L. Reduces Synovial Inflammation and Pain in Experimental Osteoarthritis.

    PubMed

    Calado, Gustavo P; Lopes, Alberto Jorge O; Costa Junior, Livio M; Lima, Francisco das Chagas A; Silva, Lucilene A; Pereira, Wanderson S; Amaral, Flávia M M do; Garcia, João Batista S; Cartágenes, Maria do Socorro de S; Nascimento, Flávia R F

    2015-01-01

    The chronicity of osteoarthritis (OA), characterized by pain and inflammation in the joints, is linked to a glutamate receptor, N-methyl-D-aspartate (NMDA). The use of plant species such as Chenopodium ambrosioides L. (Amaranthaceae) as NMDA antagonists offers a promising perspective. This work aims to analyze the antinociceptive and anti-inflammatory responses of the crude hydroalcoholic extract (HCE) of C. ambrosioides leaves in an experimental OA model. Wistar rats were separated into six groups (n = 24): clean (C), negative control (CTL-), positive control (CTL+), HCE0.5, HCE5 and HCE50. The first group received no intervention. The other groups received an intra-articular injection of sodium monoiodoacetate (MIA) (8 mg/kg) on day 0. After six hours, they were orally treated with saline, Maxicam plus (meloxicam + chondroitin sulfate) and HCE at doses of 0.5 mg/kg, 5 mg/kg and 50 mg/kg, respectively. After three, seven and ten days, clinical evaluations were performed (knee diameter, mechanical allodynia, mechanical hyperalgesia and motor activity). On the tenth day, after euthanasia, synovial fluid and draining lymph node were collected for cellular quantification, and cartilage was collected for histopathological analysis. Finally, molecular docking was performed to evaluate the compatibility of ascaridole, a monoterpene found in HCE, with the NMDA receptor. After the third day, HCE reduced knee edema. HCE5 showed less cellular infiltrate in the cartilage and synovium and lower intensities of allodynia from the third day and of hyperalgesia from the seventh day up to the last treatment day. The HCE5 and HCE50 groups improved in forced walking. In relation to molecular docking, ascaridole showed NMDA receptor binding affinity. C. ambrosioides HCE was effective in the treatment of OA because it reduced synovial inflammation and behavioral changes due to pain. This effect may be related to the antagonistic effect of ascaridole on the NMDA receptor.

  7. Inter-Individual Responses to Experimental Muscle Pain: Baseline Physiological Parameters Do Not Determine Whether Muscle Sympathetic Nerve Activity Increases or Decreases During Pain

    PubMed Central

    Kobuch, Sophie; Fazalbhoy, Azharuddin; Brown, Rachael; Macefield, Vaughan G.

    2015-01-01

    We have previously reported that there are inter-individual differences in the cardiovascular responses to experimental muscle pain, which are consistent over time: intramuscular infusion of hypertonic saline, causing pain lasting ~60 min, increases muscle sympathetic nerve activity (MSNA)—as well as blood pressure and heart rate—in certain subjects, but decrease it in others. Here, we tested the hypothesis that baseline physiological parameters (resting MSNA, heart rate, blood pressure, heart rate variability) determine the cardiovascular responses to long-lasting muscle pain. MSNA was recorded from the common peroneal nerve, together with heart rate and blood pressure, during a 45-min intramuscular infusion of hypertonic saline solution into the tibialis anterior of 50 awake human subjects (25 females and 25 males). Twenty-four subjects showed a sustained increase in mean amplitude of MSNA (160.9 ± 7.3%), while 26 showed a sustained decrease (55.1 ± 3.5%). Between the increasing and decreasing groups there were no differences in baseline MSNA (19.0 ± 1.5 vs. 18.9 ± 1.2 bursts/min), mean BP (88.1 ± 5.2 vs. 88.0 ± 3.8 mmHg), HR (74.7 ± 2.0 vs. 72.8 ± 1.8 beats/min) or heart rate variability (LF/HF 1.8 ± 0.2 vs. 2.2 ± 0.3). Furthermore, neither sex nor body mass index had any effect on whether MSNA increased or decreased during tonic muscle pain. We conclude that the measured baseline physiological parameters cannot account for the divergent sympathetic responses during tonic muscle pain. PMID:26733786

  8. Inter-Individual Responses to Experimental Muscle Pain: Baseline Physiological Parameters Do Not Determine Whether Muscle Sympathetic Nerve Activity Increases or Decreases During Pain.

    PubMed

    Kobuch, Sophie; Fazalbhoy, Azharuddin; Brown, Rachael; Macefield, Vaughan G

    2015-01-01

    We have previously reported that there are inter-individual differences in the cardiovascular responses to experimental muscle pain, which are consistent over time: intramuscular infusion of hypertonic saline, causing pain lasting ~60 min, increases muscle sympathetic nerve activity (MSNA)-as well as blood pressure and heart rate-in certain subjects, but decrease it in others. Here, we tested the hypothesis that baseline physiological parameters (resting MSNA, heart rate, blood pressure, heart rate variability) determine the cardiovascular responses to long-lasting muscle pain. MSNA was recorded from the common peroneal nerve, together with heart rate and blood pressure, during a 45-min intramuscular infusion of hypertonic saline solution into the tibialis anterior of 50 awake human subjects (25 females and 25 males). Twenty-four subjects showed a sustained increase in mean amplitude of MSNA (160.9 ± 7.3%), while 26 showed a sustained decrease (55.1 ± 3.5%). Between the increasing and decreasing groups there were no differences in baseline MSNA (19.0 ± 1.5 vs. 18.9 ± 1.2 bursts/min), mean BP (88.1 ± 5.2 vs. 88.0 ± 3.8 mmHg), HR (74.7 ± 2.0 vs. 72.8 ± 1.8 beats/min) or heart rate variability (LF/HF 1.8 ± 0.2 vs. 2.2 ± 0.3). Furthermore, neither sex nor body mass index had any effect on whether MSNA increased or decreased during tonic muscle pain. We conclude that the measured baseline physiological parameters cannot account for the divergent sympathetic responses during tonic muscle pain. PMID:26733786

  9. Brain Network Response to Acupuncture Stimuli in Experimental Acute Low Back Pain: An fMRI Study

    PubMed Central

    Shi, Yu; Liu, Ziping; Zhang, Shanshan; Li, Qiang; Guo, Shigui; Yang, Jiangming; Wu, Wen

    2015-01-01

    Most neuroimaging studies have demonstrated that acupuncture can significantly modulate brain activation patterns in healthy subjects, while only a few studies have examined clinical pain. In the current study, we combined an experimental acute low back pain (ALBP) model and functional magnetic resonance imaging (fMRI) to explore the neural mechanisms of acupuncture analgesia. All ALBP subjects first underwent two resting state fMRI scans at baseline and during a painful episode and then underwent two additional fMRI scans, once during acupuncture stimulation (ACUP) and once during tactile stimulation (SHAM) pseudorandomly, at the BL40 acupoint. Our results showed that, compared with the baseline, the pain state had higher regional homogeneity (ReHo) values in the pain matrix, limbic system, and default mode network (DMN) and lower ReHo values in frontal gyrus and temporal gyrus; compared with the OFF status, ACUP yielded broad deactivation in subjects, including nearly all of the limbic system, pain status, and DMN, and also evoked numerous activations in the attentional and somatosensory systems; compared with SHAM, we found that ACUP induced more deactivations and fewer activations in the subjects. Multiple brain networks play crucial roles in acupuncture analgesia, suggesting that ACUP exceeds a somatosensory-guided mind-body therapy for ALBP. PMID:26161117

  10. Brain Network Response to Acupuncture Stimuli in Experimental Acute Low Back Pain: An fMRI Study.

    PubMed

    Shi, Yu; Liu, Ziping; Zhang, Shanshan; Li, Qiang; Guo, Shigui; Yang, Jiangming; Wu, Wen

    2015-01-01

    Most neuroimaging studies have demonstrated that acupuncture can significantly modulate brain activation patterns in healthy subjects, while only a few studies have examined clinical pain. In the current study, we combined an experimental acute low back pain (ALBP) model and functional magnetic resonance imaging (fMRI) to explore the neural mechanisms of acupuncture analgesia. All ALBP subjects first underwent two resting state fMRI scans at baseline and during a painful episode and then underwent two additional fMRI scans, once during acupuncture stimulation (ACUP) and once during tactile stimulation (SHAM) pseudorandomly, at the BL40 acupoint. Our results showed that, compared with the baseline, the pain state had higher regional homogeneity (ReHo) values in the pain matrix, limbic system, and default mode network (DMN) and lower ReHo values in frontal gyrus and temporal gyrus; compared with the OFF status, ACUP yielded broad deactivation in subjects, including nearly all of the limbic system, pain status, and DMN, and also evoked numerous activations in the attentional and somatosensory systems; compared with SHAM, we found that ACUP induced more deactivations and fewer activations in the subjects. Multiple brain networks play crucial roles in acupuncture analgesia, suggesting that ACUP exceeds a somatosensory-guided mind-body therapy for ALBP. PMID:26161117

  11. Is it better to have controlled and lost than never to have controlled at all? An experimental investigation of control over pain.

    PubMed

    Crombez, Geert; Eccleston, Christopher; De Vlieger, Petra; Van Damme, Stefaan; De Clercq, Armand

    2008-07-31

    Trying to control pain is a common human goal. But little is know about what happens when one loses control over pain. This paper reports an experiment with 74 healthy volunteers, half of whom were given control over a pain stimulus and subsequently lost control, and half of whom never had control over the pain. This study investigates whether having had control and lost it would result in a more unpleasant pain experience, more fear about impending pain, a heightened vigilance to pain, and greater interference on a secondary task. Participants in the experimental group first learned to avoid a painful stimulus by correctly responding to a card sorting task, but later on lost control over the painful stimulus. In the yoked comparison group, participants had no control over the painful stimulus from the beginning. Results indicated that losing control over pain and, relatedly, attempting to control uncontrollable pain have significant costs such as a higher fear of the impending pain stimulus and retarded performance on a secondary task. When attempts to avoid pain are blocked, individuals persist in their avoidance attempts, try harder, and narrow their focus of attention upon the problem to be solved. These findings are discussed within the context of a dual process model of coping with uncontrollable adverse events [Brandtstädter J, Renner G. Tenacious goal pursuit and flexible goal adjustment: explication and age-related analysis of assimilative and accommodative strategies of coping. Psychol Aging 1990;5:58-67] and possible mechanisms for perseverance with ineffective solutions.

  12. High- and low-frequency transcutaneous electrical nerve stimulation does not reduce experimental pain in elderly individuals

    PubMed Central

    Bergeron-Vézina, Kayla; Corriveau, Hélène; Martel, Marylie; Harvey, Marie-Philippe; Léonard, Guillaume

    2015-01-01

    Abstract Despite its widespread clinical use, the efficacy of transcutaneous electrical nerve stimulation (TENS) remains poorly documented in elderly individuals. In this randomized, double-blind crossover study, we compared the efficacy of high-frequency (HF), low-frequency (LF), and placebo (P) TENS in a group of 15 elderly adults (mean age: 67 ± 5 years). The effect of HF-, LF-, and P-TENS was also evaluated in a group of 15 young individuals (26 ± 5 years; same study design) to validate the effectiveness of the TENS protocols that were used in the elderly group. Each participant came to the laboratory on 3 separate occasions to receive, in random order, HF-, LF-, and P-TENS. Pain intensity and pain perception thresholds were assessed before, during, and after TENS, using an experimental heat pain paradigm. For the young group, there was a significant decrease in pain intensity during and after HF- and LF-TENS when compared with baseline, with both HF- and LF-TENS being superior to P-TENS. In the older group, HF- and LF-TENS did not reduce pain when compared with baseline and no difference was observed between the 2 active TENS sessions and P-TENS. High-frequency, LF-, and P-TENS all increased pain thresholds in young individuals, whereas in older individuals, only LF-TENS increased pain thresholds. Taken together, these results suggest that TENS is effective in young, but not in older, individuals. Future studies should be conducted to confirm these results in pain populations and to identify strategies that could enhance the effect of TENS in the elderly. PMID:26101836

  13. High- and low-frequency transcutaneous electrical nerve stimulation does not reduce experimental pain in elderly individuals.

    PubMed

    Bergeron-Vézina, Kayla; Corriveau, Hélène; Martel, Marylie; Harvey, Marie-Philippe; Léonard, Guillaume

    2015-10-01

    Despite its widespread clinical use, the efficacy of transcutaneous electrical nerve stimulation (TENS) remains poorly documented in elderly individuals. In this randomized, double-blind crossover study, we compared the efficacy of high-frequency (HF), low-frequency (LF), and placebo (P) TENS in a group of 15 elderly adults (mean age: 67 ± 5 years). The effect of HF-, LF-, and P-TENS was also evaluated in a group of 15 young individuals (26 ± 5 years; same study design) to validate the effectiveness of the TENS protocols that were used in the elderly group. Each participant came to the laboratory on 3 separate occasions to receive, in random order, HF-, LF-, and P-TENS. Pain intensity and pain perception thresholds were assessed before, during, and after TENS, using an experimental heat pain paradigm. For the young group, there was a significant decrease in pain intensity during and after HF- and LF-TENS when compared with baseline, with both HF- and LF-TENS being superior to P-TENS. In the older group, HF- and LF-TENS did not reduce pain when compared with baseline and no difference was observed between the 2 active TENS sessions and P-TENS. High-frequency, LF-, and P-TENS all increased pain thresholds in young individuals, whereas in older individuals, only LF-TENS increased pain thresholds. Taken together, these results suggest that TENS is effective in young, but not in older, individuals. Future studies should be conducted to confirm these results in pain populations and to identify strategies that could enhance the effect of TENS in the elderly.

  14. Sensory Re-Weighting in Human Bipedal Postural Control: The Effects of Experimentally-Induced Plantar Pain.

    PubMed

    Pradels, Antoine; Pradon, Didier; Hlavačková, Petra; Diot, Bruno; Vuillerme, Nicolas

    2013-01-01

    The present study was designed to assess the effects of experimentally-induced plantar pain on the displacement of centre of foot pressure during unperturbed upright stance in different sensory conditions of availability and/or reliability of visual input and somatosensory input from the vestibular system and neck. To achieve this goal, fourteen young healthy adults were asked to stand as still as possible in three sensory conditions: (1) No-vision, (2) Vision, and (3) No-vision - Head tilted backward, during two experimental conditions: (1) a No-pain condition, and (2) a condition when a painful stimulation was applied to the plantar surfaces of both feet (Plantar-pain condition). Centre of foot pressure (CoP) displacements were recorded using a force platform. Results showed that (1) experimentally-induced plantar pain increased CoP displacements in the absence of vision (No-vision condition), (2) this deleterious effect was more accentuated when somatosensory information from the vestibular and neck was altered (No-vision - Head tilted backward condition) and (3) this deleterious effect was suppressed when visual information was available (Vision condition). From a fundamental point of view, these results lend support to the sensory re-weighting hypothesis whereby the central nervous system dynamically and selectively adjusts the relative contributions of sensory inputs (i.e. the sensory weightings) in order to maintain balance when one or more sensory channels are altered by the task (novel or challenging), environmental or individual conditions. From a clinical point of view, the present findings further suggest that prevention and treatment of plantar pain may be relevant for the preservation or improvement of balance control, particularly in situations (or individuals) in which information provided by the visual, neck proprioceptive and vestibular systems is unavailable or disrupted. PMID:23840337

  15. Sensory Re-Weighting in Human Bipedal Postural Control: The Effects of Experimentally-Induced Plantar Pain

    PubMed Central

    Pradels, Antoine; Pradon, Didier; Hlavačková, Petra; Diot, Bruno; Vuillerme, Nicolas

    2013-01-01

    The present study was designed to assess the effects of experimentally-induced plantar pain on the displacement of centre of foot pressure during unperturbed upright stance in different sensory conditions of availability and/or reliability of visual input and somatosensory input from the vestibular system and neck. To achieve this goal, fourteen young healthy adults were asked to stand as still as possible in three sensory conditions: (1) No-vision, (2) Vision, and (3) No-vision – Head tilted backward, during two experimental conditions: (1) a No-pain condition, and (2) a condition when a painful stimulation was applied to the plantar surfaces of both feet (Plantar-pain condition). Centre of foot pressure (CoP) displacements were recorded using a force platform. Results showed that (1) experimentally-induced plantar pain increased CoP displacements in the absence of vision (No-vision condition), (2) this deleterious effect was more accentuated when somatosensory information from the vestibular and neck was altered (No-vision – Head tilted backward condition) and (3) this deleterious effect was suppressed when visual information was available (Vision condition). From a fundamental point of view, these results lend support to the sensory re-weighting hypothesis whereby the central nervous system dynamically and selectively adjusts the relative contributions of sensory inputs (i.e. the sensory weightings) in order to maintain balance when one or more sensory channels are altered by the task (novel or challenging), environmental or individual conditions. From a clinical point of view, the present findings further suggest that prevention and treatment of plantar pain may be relevant for the preservation or improvement of balance control, particularly in situations (or individuals) in which information provided by the visual, neck proprioceptive and vestibular systems is unavailable or disrupted. PMID:23840337

  16. An experimental study of shared sensitivity to physical pain and social rejection.

    PubMed

    Eisenberger, Naomi I; Jarcho, Johanna M; Lieberman, Matthew D; Naliboff, Bruce D

    2006-12-15

    Recent evidence points to a possible overlap in the neural systems underlying the distressing experience that accompanies physical pain and social rejection (Eisenberger et al., 2003). The present study tested two hypotheses that stem from this suggested overlap, namely: (1) that baseline sensitivity to physical pain will predict sensitivity to social rejection and (2) that experiences that heighten social distress will heighten sensitivity to physical pain as well. In the current study, participants' baseline cutaneous heat pain unpleasantness thresholds were assessed prior to the completion of a task that manipulated feelings of social distress. During this task, participants played a virtual ball-tossing game, allegedly with two other individuals, in which they were either continuously included (social inclusion condition) or they were left out of the game by either never being included or by being overtly excluded (social rejection conditions). At the end of the game, three pain stimuli were delivered and participants rated the unpleasantness of each. Results indicated that greater baseline sensitivity to pain (lower pain unpleasantness thresholds) was associated with greater self-reported social distress in response to the social rejection conditions. Additionally, for those in the social rejection conditions, greater reports of social distress were associated with greater reports of pain unpleasantness to the thermal stimuli delivered at the end of the game. These results provide additional support for the hypothesis that pain distress and social distress share neurocognitive substrates. Implications for clinical populations are discussed. PMID:16890354

  17. Pain-related fear predicts reduced spinal motion following experimental back injury.

    PubMed

    Trost, Zina; France, Christopher R; Sullivan, Michael J; Thomas, James S

    2012-05-01

    The current study examined the prospective relationship between pain-related fear and altered motor behavior, as well as perceived interference, among 51 healthy participants following induction of delayed-onset muscle soreness (DOMS) to the trunk extensor muscles. Healthy participants without history of back pain completed standardized reaches to high and low targets at self-paced and rapid speeds before and after induction of acute low back pain using a DOMS paradigm. Pain-related fear was assessed prior to DOMS induction. Three-dimensional joint motions of the thoracic spine, lumbar spine, and hip were recorded using an electromagnetic tracking device. DOMS-induced differences between high- and low-fear participants were observed for lumbar spine flexion, but not for thoracic or hip flexion. Pain-related fear scores were not predictive of lumbar flexion during baseline, but predicted reduced lumbar flexion during self- and fast-paced trials to low target locations once DOMS was induced. Pain-related fear was likewise predictive of perceived interference in life activities following DOMS induction. The findings suggest that initially pain-free individuals with high pain-related fear adopt avoidant spinal strategies during common reaching movements shortly after injury is sustained, which may comprise a risk factor for future pain and disability. PMID:22377437

  18. Dysfunctional pain inhibition in patients with chronic whiplash-associated disorders: an experimental study.

    PubMed

    Daenen, Liesbeth; Nijs, Jo; Roussel, Nathalie; Wouters, Kristien; Van Loo, Michel; Cras, Patrick

    2013-01-01

    Inefficient endogenous pain inhibition, in particular impaired conditioned pain modulation (CPM), may disturb central pain processing in patients with chronic whiplash-associated disorders (WAD). Previous studies revealed that abnormal central pain processing is responsible for a wide range of symptoms in patients with chronic WAD. Hence, the present study aimed at examining the functioning of descending pain inhibitory pathways, and in particular CPM, in patients with chronic WAD. Thirty-five patients with chronic WAD and 31 healthy controls were subjected to an experiment evaluating CPM. CPM was induced by an inflated occlusion cuff and evaluated by comparing temporal summation (TS) of pressure pain prior to and during cuff inflation. Temporal summation was provoked by means of 10 consecutive pressure pulses at upper and lower limb location. Pain intensity of first, fifth, and 10th pressure pulse was rated. During heterotopic noxious conditioning stimulation, TS of pressure pain was significantly depleted among healthy controls. In contrast, TS was quite similar prior to and during cuff inflation in chronic WAD, providing evidence for dysfunctional CPM in patients with chronic WAD. The present study demonstrates a lack of endogenous pain inhibitory pathways, and in particularly CPM, in patients with chronic WAD, and hence provides additional evidence for the presence of central sensitization in chronic WAD.

  19. Racial bias in pain perception and response: experimental examination of automatic and deliberate processes

    PubMed Central

    Mathur, Vani A.; Richeson, Jennifer A.; Paice, Judith A.; Muzyka, Michael; Chiao, Joan Y.

    2014-01-01

    Racial disparities in pain treatment pose a significant public health and scientific problem. Prior studies demonstrate clinicians and non-clinicians are less perceptive, and suggest less treatment for, the pain of African Americans, relative to European Americans. Here we investigate the effects of explicit/implicit patient race presentation, patient race, and perceiver race on pain perception and response. African American and European American participants rated pain perception, empathy, helping motivation, and treatment suggestion in response to vignettes about patients’ pain. Vignettes were accompanied by a rapid (implicit), or static (explicit) presentation of an African or European American patient’s face. Participants perceived and responded more to European American patients in the implicit prime condition, when the effect of patient race was below the level of conscious regulation. This effect was reversed when patient race was presented explicitly. Additionally, female participants perceived and responded more to the pain of all patients, relative to male participants, and in the implicit prime condition, African American participants were more perceptive and responsive than European Americans to the pain of all patients. Taken together, these results suggest that known disparities in pain treatment may be largely due to automatic (below the level of conscious regulation), rather than deliberate (subject to conscious regulation) biases. These biases were not associated with traditional implicit measures of racial attitudes, suggesting that biases in pain perception and response may be independent of general prejudice. Perspective Results suggest racial biases in pain perception and treatment are at least partially due to automatic processes. When the relevance of patient race is made explicit, however, biases are attenuated and even reversed. We also find preliminary evidence that African Americans may be more sensitive to the pain of others than

  20. Pelvic organ cross-sensitization to enhance bladder and urethral pain behaviors in rats with experimental colitis.

    PubMed

    Yoshikawa, S; Kawamorita, N; Oguchi, T; Funahashi, Y; Tyagi, P; Chancellor, M B; Yoshimura, N

    2015-01-22

    Neural cross-sensitization has been postulated as a mechanism underlying overlaps of chronic pelvic pain disorders such as bladder pain syndrome/interstitial cystitis (BPS/IC) and irritable bowel syndrome (IBS). Animals with experimental colitis have been used to study the underlying mechanisms for overlapped pelvic pain symptoms, and shown to exhibit bladder overactivity evidenced by frequent voiding; however, it has not directly been evaluated whether pain sensation derived from the lower urinary tract is enhanced in colitis models. Also, the cross-sensitization between the colon and urethra has not been studied previously. In the present study, we therefore investigated pain behaviors induced by nociceptive stimuli in the lower urinary tract and the involvement of C-fiber afferent pathways using rats with colitis induced by intracolonic application of 2,4,6-trinitrobenzenesulfonic acid (TNBS). In TNBS-induced colitis rats at 10 days, intravesical application of resiniferatoxin (RTx) induced a significantly greater number of episodes of both licking and freezing behaviors, which were reduced by capsaicin-sensitive C-fiber afferent desensitization. Histochemical studies using fluorescent dye tracers injected into the colon, bladder or urethra showed that dichotomized afferent neurons comprised 6.9-14.5% of L1, L6 and S1 dorsal root ganglion (DRG) neurons innervating the colon or the lower urinary tract. Transient receptor potential vanilloid 1 (TRPV1) mRNA expression was significantly increased in, the bladder, urethra and S1 DRG in colitis rats. An increase in myeloperoxidase (MPO) activity was found in the colon, but not in the bladder or urethra after intracolonic TNBS treatment. These results indicate that TNBS-induced colitis increased pain sensitivity in the bladder and urethra via activation of C-fiber afferent pathways due to colon-to-bladder and colon-to-urethral cross-sensitization, suggesting the contribution of pelvic organ cross

  1. The role of operant conditioning in chronic pain: an experimental investigation.

    PubMed

    Flor, Herta; Knost, Bärbel; Birbaumer, Niels

    2002-01-01

    The role of operant conditioning for the development and maintenance of chronic pain was examined in 30 chronic back pain patients (CBP) and 30 matched healthy controls. Half of each group was reinforced for increased, half for decreased pain reports while EEG, EOG, heart rate, skin conductance and muscle tension levels were recorded. Both groups showed similar learning rates, however, the CBP patients displayed slower extinction of both the verbal and the cortical (N150) pain response. In addition, the CBP group displayed prolonged elevated electromyogram levels to the task. These data suggest that CBP patients are more easily influenced by operant conditioning factors than healthy controls and this susceptibility may add to the maintenance of the chronic pain problem.

  2. Equal Improvement in Men and Women in the Treatment of Urologic Chronic Pelvic Pain Syndrome Using a Multi-modal Protocol with an Internal Myofascial Trigger Point Wand.

    PubMed

    Anderson, Rodney U; Wise, David; Sawyer, Tim; Nathanson, Brian H; Nevin Smith, J

    2016-06-01

    Both men and women require treatment for urologic chronic pelvic pain syndromes (UCPPS), which includes interstitial cystitis/painful bladder syndrome, pelvic floor dysfunction, and chronic prostatitis/chronic pelvic pain syndrome. However, it is unknown if men and women respond differently to a protocol that includes specific physical therapy self-treatment using an internal trigger point wand and training in paradoxical relaxation. We performed a retrospective analysis by gender in a single arm, open label, single center clinical trial designed to evaluate the safety and effectiveness of a protocol for the treatment of UCPPS from October, 2008 to May, 2011. 314 adult men (79.9 %) and 79 (20.1 %) women met inclusion criteria. The median duration of symptoms was 60 months. The protocol required an initial 6-day clinic for training followed by a 6-month self-treatment period. The treatment included self-administered pelvic floor trigger point release with an internal trigger point device for physical therapy along with paradoxical relaxation training. Notable gender differences in prior treatments were observed. Men had a lower median [Interquartile Range] NIH-CPSI score at baseline than women (27 [21, 31] vs. 29 [22, 33], p = 0.04). Using a 1-10 scale with 10 = Most Severe, the median reduction in trigger point sensitivity was 3 units for both men and women after 6 months therapy (p = 0.74). A modified Intention to Treat analysis and a multivariate regression analysis found similar results. We conclude that men and women have similar, significant reductions in trigger point sensitivity with this protocol. PMID:26721470

  3. Equal Improvement in Men and Women in the Treatment of Urologic Chronic Pelvic Pain Syndrome Using a Multi-modal Protocol with an Internal Myofascial Trigger Point Wand.

    PubMed

    Anderson, Rodney U; Wise, David; Sawyer, Tim; Nathanson, Brian H; Nevin Smith, J

    2016-06-01

    Both men and women require treatment for urologic chronic pelvic pain syndromes (UCPPS), which includes interstitial cystitis/painful bladder syndrome, pelvic floor dysfunction, and chronic prostatitis/chronic pelvic pain syndrome. However, it is unknown if men and women respond differently to a protocol that includes specific physical therapy self-treatment using an internal trigger point wand and training in paradoxical relaxation. We performed a retrospective analysis by gender in a single arm, open label, single center clinical trial designed to evaluate the safety and effectiveness of a protocol for the treatment of UCPPS from October, 2008 to May, 2011. 314 adult men (79.9 %) and 79 (20.1 %) women met inclusion criteria. The median duration of symptoms was 60 months. The protocol required an initial 6-day clinic for training followed by a 6-month self-treatment period. The treatment included self-administered pelvic floor trigger point release with an internal trigger point device for physical therapy along with paradoxical relaxation training. Notable gender differences in prior treatments were observed. Men had a lower median [Interquartile Range] NIH-CPSI score at baseline than women (27 [21, 31] vs. 29 [22, 33], p = 0.04). Using a 1-10 scale with 10 = Most Severe, the median reduction in trigger point sensitivity was 3 units for both men and women after 6 months therapy (p = 0.74). A modified Intention to Treat analysis and a multivariate regression analysis found similar results. We conclude that men and women have similar, significant reductions in trigger point sensitivity with this protocol.

  4. Experimental Muscle Pain Impairs the Synergistic Modular Control of Neck Muscles.

    PubMed

    Gizzi, Leonardo; Muceli, Silvia; Petzke, Frank; Falla, Deborah

    2015-01-01

    A motor task can be performed via different patterns of muscle activation that show regularities that can be factorized in combinations of a reduced number of muscle groupings (also referred to as motor modules, or muscle synergies). In this study we evaluate whether an acute noxious stimulus induces a change in the way motor modules are combined to generate movement by neck muscles. The neck region was selected as it is a region with potentially high muscular redundancy. We used the motor modules framework to assess the redistribution of muscular activity of 12 muscles (6 per side) in the neck region of 8 healthy individuals engaged in a head and neck aiming task, in non-painful conditions (baseline, isotonic saline injection, post pain) and after the injection of hypertonic saline into the right splenius capitis muscle. The kinematics of the task was similar in the painful and control conditions. A general decrease of activity was noted for the injected muscle during the painful condition together with an increase or decrease of the activity of the other muscles. Subjects did not adopt shared control strategies (motor modules inter subject similarity at baseline 0.73±0.14); the motor modules recorded during the painful condition could not be used to reconstruct the activation patterns of the control conditions, and the painful stimulus triggered a subject-specific redistribution of muscular activation (i.e., in some subjects the activity of a given muscle increased, whereas in other subjects it decreased with pain). Alterations of afferent input (i.e., painful stimulus) influenced motor control at a multi muscular level, but not kinematic output. These findings provide new insights into the motor adaptation to pain.

  5. Experimental Muscle Pain Impairs the Synergistic Modular Control of Neck Muscles

    PubMed Central

    Gizzi, Leonardo; Muceli, Silvia; Petzke, Frank; Falla, Deborah

    2015-01-01

    A motor task can be performed via different patterns of muscle activation that show regularities that can be factorized in combinations of a reduced number of muscle groupings (also referred to as motor modules, or muscle synergies). In this study we evaluate whether an acute noxious stimulus induces a change in the way motor modules are combined to generate movement by neck muscles. The neck region was selected as it is a region with potentially high muscular redundancy. We used the motor modules framework to assess the redistribution of muscular activity of 12 muscles (6 per side) in the neck region of 8 healthy individuals engaged in a head and neck aiming task, in non-painful conditions (baseline, isotonic saline injection, post pain) and after the injection of hypertonic saline into the right splenius capitis muscle. The kinematics of the task was similar in the painful and control conditions. A general decrease of activity was noted for the injected muscle during the painful condition together with an increase or decrease of the activity of the other muscles. Subjects did not adopt shared control strategies (motor modules inter subject similarity at baseline 0.73±0.14); the motor modules recorded during the painful condition could not be used to reconstruct the activation patterns of the control conditions, and the painful stimulus triggered a subject-specific redistribution of muscular activation (i.e., in some subjects the activity of a given muscle increased, whereas in other subjects it decreased with pain). Alterations of afferent input (i.e., painful stimulus) influenced motor control at a multi muscular level, but not kinematic output. These findings provide new insights into the motor adaptation to pain. PMID:26382606

  6. A cuckoo search algorithm for multimodal optimization.

    PubMed

    Cuevas, Erik; Reyna-Orta, Adolfo

    2014-01-01

    Interest in multimodal optimization is expanding rapidly, since many practical engineering problems demand the localization of multiple optima within a search space. On the other hand, the cuckoo search (CS) algorithm is a simple and effective global optimization algorithm which can not be directly applied to solve multimodal optimization problems. This paper proposes a new multimodal optimization algorithm called the multimodal cuckoo search (MCS). Under MCS, the original CS is enhanced with multimodal capacities by means of (1) the incorporation of a memory mechanism to efficiently register potential local optima according to their fitness value and the distance to other potential solutions, (2) the modification of the original CS individual selection strategy to accelerate the detection process of new local minima, and (3) the inclusion of a depuration procedure to cyclically eliminate duplicated memory elements. The performance of the proposed approach is compared to several state-of-the-art multimodal optimization algorithms considering a benchmark suite of fourteen multimodal problems. Experimental results indicate that the proposed strategy is capable of providing better and even a more consistent performance over existing well-known multimodal algorithms for the majority of test problems yet avoiding any serious computational deterioration. PMID:25147850

  7. A cuckoo search algorithm for multimodal optimization.

    PubMed

    Cuevas, Erik; Reyna-Orta, Adolfo

    2014-01-01

    Interest in multimodal optimization is expanding rapidly, since many practical engineering problems demand the localization of multiple optima within a search space. On the other hand, the cuckoo search (CS) algorithm is a simple and effective global optimization algorithm which can not be directly applied to solve multimodal optimization problems. This paper proposes a new multimodal optimization algorithm called the multimodal cuckoo search (MCS). Under MCS, the original CS is enhanced with multimodal capacities by means of (1) the incorporation of a memory mechanism to efficiently register potential local optima according to their fitness value and the distance to other potential solutions, (2) the modification of the original CS individual selection strategy to accelerate the detection process of new local minima, and (3) the inclusion of a depuration procedure to cyclically eliminate duplicated memory elements. The performance of the proposed approach is compared to several state-of-the-art multimodal optimization algorithms considering a benchmark suite of fourteen multimodal problems. Experimental results indicate that the proposed strategy is capable of providing better and even a more consistent performance over existing well-known multimodal algorithms for the majority of test problems yet avoiding any serious computational deterioration.

  8. Hypnosis and Local Anesthesia for Dental Pain Relief-Alternative or Adjunct Therapy?-A Randomized, Clinical-Experimental Crossover Study.

    PubMed

    Wolf, Thomas Gerhard; Wolf, Dominik; Callaway, Angelika; Below, Dagna; d'Hoedt, Bernd; Willershausen, Brita; Daubländer, Monika

    2016-01-01

    This prospective randomized clinical crossover trial was designed to compare hypnosis and local anesthesia for experimental dental pain relief. Pain thresholds of the dental pulp were determined. A targeted standardized pain stimulus was applied and rated on the Visual Analogue Scale (0-10). The pain threshold was lower under hypnosis (58.3 ± 17.3, p < .001), maximal (80.0) under local anesthesia. The pain stimulus was scored higher under hypnosis (3.9 ± 3.8) than with local anesthesia (0.0, p < .001). Local anesthesia was superior to hypnosis and is a safe and effective method for pain relief in dentistry. Hypnosis seems to produce similar effects observed under sedation. It can be used in addition to local anesthesia and in individual cases as an alternative for pain control in dentistry.

  9. Hypnosis and Local Anesthesia for Dental Pain Relief-Alternative or Adjunct Therapy?-A Randomized, Clinical-Experimental Crossover Study.

    PubMed

    Wolf, Thomas Gerhard; Wolf, Dominik; Callaway, Angelika; Below, Dagna; d'Hoedt, Bernd; Willershausen, Brita; Daubländer, Monika

    2016-01-01

    This prospective randomized clinical crossover trial was designed to compare hypnosis and local anesthesia for experimental dental pain relief. Pain thresholds of the dental pulp were determined. A targeted standardized pain stimulus was applied and rated on the Visual Analogue Scale (0-10). The pain threshold was lower under hypnosis (58.3 ± 17.3, p < .001), maximal (80.0) under local anesthesia. The pain stimulus was scored higher under hypnosis (3.9 ± 3.8) than with local anesthesia (0.0, p < .001). Local anesthesia was superior to hypnosis and is a safe and effective method for pain relief in dentistry. Hypnosis seems to produce similar effects observed under sedation. It can be used in addition to local anesthesia and in individual cases as an alternative for pain control in dentistry. PMID:27585724

  10. [Treatment of chronic back pain with antidepressant cymbalta: an experimental study].

    PubMed

    Voznesenskaia, T G; Leonova, A R; Kaverina, I V

    2007-01-01

    Thirty-two patients at the acute stage of chronic back pain have been studied. Cymbalta was used as a monotherapy in dosage 60 mg daily during 6 weeks simultaneously with traditional non-pharmacological therapy. Treatment efficacy was assessed using self-rating methods and quantitative scales measuring pain intensity as well as Spilberger trait/state anxiety inventory, Beck depression scale, Plutchik scale measuring psychological defense mechanisms, quality of sleep, quality of life and evaluation of autonomic dysfunction. The treatment with cymbalta resulted in significant reduction of pain in 90% patients, with full stopping of the syndrome in 10% and marked reduction in 55%. The stopping of pain syndrome was correlated with significant improvement of emotional status and quality of life and sleep normalization of the patients. PMID:18379477

  11. The lidocaine metabolite N-ethylglycine has antinociceptive effects in experimental inflammatory and neuropathic pain.

    PubMed

    Werdehausen, Robert; Mittnacht, Sebastian; Bee, Lucy A; Minett, Michael S; Armbruster, Anja; Bauer, Inge; Wood, John N; Hermanns, Henning; Eulenburg, Volker

    2015-09-01

    Glycine transporter 1 (GlyT1) plays a crucial role in regulating extracellular glycine concentrations and might thereby constitute a new drug target for the modulation of glycinergic inhibition in pain signaling. Consistent with this view, inhibition of GlyT1 has been found to induce antinociceptive effects in various animal pain models. We have shown previously that the lidocaine metabolite N-ethylglycine (EG) reduces GlyT1-dependent glycine uptake by functioning as an artificial substrate for this transporter. Here, we show that EG is specific for GlyT1 and that in rodent models of inflammatory and neuropathic pain, systemic treatment with EG results in an efficient amelioration of hyperalgesia and allodynia without affecting acute pain. There was no effect on motor coordination or the development of inflammatory edema. No adverse neurological effects were observed after repeated high-dose application of EG. EG concentrations both in blood and spinal fluid correlated with an increase of glycine concentration in spinal fluid. The time courses of the EG and glycine concentrations corresponded well with the antinociceptive effect. Additionally, we found that EG reduced the increase in neuronal firing of wide-dynamic-range neurons caused by inflammatory pain induction. These findings suggest that systemically applied lidocaine exerts antihyperalgesic effects through its metabolite EG in vivo, by enhancing spinal inhibition of pain processing through GlyT1 modulation and subsequent increase of glycine concentrations at glycinergic inhibitory synapses. EG and other substrates of GlyT1, therefore, may be a useful therapeutic agent in chronic pain states involving spinal disinhibition.

  12. Effects of COX inhibition on experimental pain and hyperalgesia during and after remifentanil infusion in humans.

    PubMed

    Lenz, Harald; Raeder, Johan; Draegni, Tomas; Heyerdahl, Fridtjof; Schmelz, Martin; Stubhaug, Audun

    2011-06-01

    Opioids may enhance pain sensitivity resulting in opioid-induced hyperalgesia (OIH). Activation of spinal cyclooxygenase may play a role in the development of OIH. The aim of this study was to demonstrate remifentanil-induced postinfusion hyperalgesia in an electrical pain and a cold pain model, and to investigate whether COX-2 (parecoxib) or COX-1 (ketorolac) inhibition could prevent hyperalgesia after remifentanil infusion. Sixteen healthy males were enrolled in this randomized, double-blind, placebo-controlled crossover study. Each subject went through 4 sessions: control, remifentanil, parecoxib+remifentanil, and ketorolac+remifentanil. Transcutaneous electrical stimulation induced acute pain and areas of pinprick hyperalgesia. The areas of pinprick hyperalgesia were assessed before, during, and after a 30-minute infusion of either remifentanil or saline. The cold-pressor test (CPT) was performed before, at the end of, and 1 hour after the infusions. The subjects received a bolus of either saline, 40 mg parecoxib, or 30 mg ketorolac intravenously after the first CPT. The areas of pinprick hyperalgesia and CPT pain after the end of remifentanil infusion increased significantly compared to control (P < 0.001 and P = 0.005, respectively). Pretreatment with parecoxib or ketorolac reduced the postinfusion area of pinprick hyperalgesia (P < 0.001 and P = 0.001, respectively), compared to the remifentanil group. Parecoxib reduced the area significantly more than ketorolac (P = 0.009). In the CPT, pretreatment with parecoxib or ketorolac did not prevent postinfusion hyperalgesia. These results demonstrated OIH in both models, and may suggest that COX-2 inhibition is more important than COX-1 inhibition in reducing hyperalgesia. Remifentanil-induced hyperalgesia was demonstrated for both electrically induced pain and cold-pressor pain. Both parecoxib and ketorolac prevented hyperalgesia in the electrical model, parecoxib to a larger extent.

  13. The lidocaine metabolite N-ethylglycine has antinociceptive effects in experimental inflammatory and neuropathic pain

    PubMed Central

    Werdehausen, Robert; Mittnacht, Sebastian; Bee, Lucy A.; Minett, Michael S.; Armbruster, Anja; Bauer, Inge; Wood, John N.; Hermanns, Henning; Eulenburg, Volker

    2015-01-01

    Abstract Glycine transporter 1 (GlyT1) plays a crucial role in regulating extracellular glycine concentrations and might thereby constitute a new drug target for the modulation of glycinergic inhibition in pain signaling. Consistent with this view, inhibition of GlyT1 has been found to induce antinociceptive effects in various animal pain models. We have shown previously that the lidocaine metabolite N-ethylglycine (EG) reduces GlyT1-dependent glycine uptake by functioning as an artificial substrate for this transporter. Here, we show that EG is specific for GlyT1 and that in rodent models of inflammatory and neuropathic pain, systemic treatment with EG results in an efficient amelioration of hyperalgesia and allodynia without affecting acute pain. There was no effect on motor coordination or the development of inflammatory edema. No adverse neurological effects were observed after repeated high-dose application of EG. EG concentrations both in blood and spinal fluid correlated with an increase of glycine concentration in spinal fluid. The time courses of the EG and glycine concentrations corresponded well with the antinociceptive effect. Additionally, we found that EG reduced the increase in neuronal firing of wide-dynamic-range neurons caused by inflammatory pain induction. These findings suggest that systemically applied lidocaine exerts antihyperalgesic effects through its metabolite EG in vivo, by enhancing spinal inhibition of pain processing through GlyT1 modulation and subsequent increase of glycine concentrations at glycinergic inhibitory synapses. EG and other substrates of GlyT1, therefore, may be a useful therapeutic agent in chronic pain states involving spinal disinhibition. PMID:25932687

  14. Untreated pain, narcotics regulation, and global health ideologies.

    PubMed

    King, Nicholas B; Fraser, Veronique

    2013-01-01

    Pain management is marginalized or ignored, with millions of people worldwide unnecessarily living with untreated pain. Reducing global inequalities in untreated pain requires a concerted global effort, say Veronique Fraser and colleagues, which must attend to the complexity of pain and promote multimodal, multidisciplinary pain management.

  15. A Clinical Experimental Model to Evaluate Analgesic Effect of Remote Ischemic Preconditioning in Acute Postoperative Pain

    PubMed Central

    Pereira, Francisco Elano Carvalho; Mello, Irene Lopes; Pimenta, Fernando Heladio de Oliveira Medeiros; Costa, Debora Maia; Wong, Deysi Viviana Tenazoa; Fernandes, Claudia Regina; Lima Junior, Roberto César; Gomes, Josenília M. Alves

    2016-01-01

    This study aims to evaluate the viability of a clinical model of remote ischemic preconditioning (RIPC) and its analgesic effects. It is a prospective study with twenty (20) patients randomly divided into two groups: control group and RIPC group. The opioid analgesics consumption in the postoperative period, the presence of secondary mechanical hyperalgesia, the scores of postoperative pain by visual analog scale, and the plasma levels interleukins (IL-6) were evaluated. The tourniquet applying after spinal anesthetic block was safe, producing no pain for all patients in the tourniquet group. The total dose of morphine consumption in 24 hours was significantly lower in RIPC group than in the control group (p = 0.0156). The intensity analysis of rest pain, pain during coughing and pain in deep breathing, showed that visual analogue scale (VAS) scores were significantly lower in RIPC group compared to the control group: p = 0.0087, 0.0119, and 0.0015, respectively. There were no differences between groups in the analysis of presence or absence of mechanical hyperalgesia (p = 0.0704) and in the serum levels of IL-6 dosage over time (p < 0.0001). This clinical model of remote ischemic preconditioning promoted satisfactory analgesia in patients undergoing conventional cholecystectomy, without changing serum levels of IL-6. PMID:27446611

  16. A Clinical Experimental Model to Evaluate Analgesic Effect of Remote Ischemic Preconditioning in Acute Postoperative Pain.

    PubMed

    Pereira, Francisco Elano Carvalho; Mello, Irene Lopes; Pimenta, Fernando Heladio de Oliveira Medeiros; Costa, Debora Maia; Wong, Deysi Viviana Tenazoa; Fernandes, Claudia Regina; Lima Junior, Roberto César; Gomes, Josenília M Alves

    2016-01-01

    This study aims to evaluate the viability of a clinical model of remote ischemic preconditioning (RIPC) and its analgesic effects. It is a prospective study with twenty (20) patients randomly divided into two groups: control group and RIPC group. The opioid analgesics consumption in the postoperative period, the presence of secondary mechanical hyperalgesia, the scores of postoperative pain by visual analog scale, and the plasma levels interleukins (IL-6) were evaluated. The tourniquet applying after spinal anesthetic block was safe, producing no pain for all patients in the tourniquet group. The total dose of morphine consumption in 24 hours was significantly lower in RIPC group than in the control group (p = 0.0156). The intensity analysis of rest pain, pain during coughing and pain in deep breathing, showed that visual analogue scale (VAS) scores were significantly lower in RIPC group compared to the control group: p = 0.0087, 0.0119, and 0.0015, respectively. There were no differences between groups in the analysis of presence or absence of mechanical hyperalgesia (p = 0.0704) and in the serum levels of IL-6 dosage over time (p < 0.0001). This clinical model of remote ischemic preconditioning promoted satisfactory analgesia in patients undergoing conventional cholecystectomy, without changing serum levels of IL-6. PMID:27446611

  17. 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.

  18. 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

  19. Citral: a monoterpene with prophylactic and therapeutic anti-nociceptive effects in experimental models of acute and chronic pain.

    PubMed

    Nishijima, Catarine M; Ganev, Ellen G; Mazzardo-Martins, Leidiane; Martins, Daniel F; Rocha, Lúcia R M; Santos, Adair R S; Hiruma-Lima, Clelia A

    2014-08-01

    Citral (3,7-dimethyl-2,6-octadienal) is an open-chain monoterpenoid present in the essential oils of several medicinal plants. The aim of this work was to evaluate the effects of orally administered citral in experimental models of acute and chronic nociception, inflammation, and gastric ulcers caused by non-steroidal anti-inflammatory drugs (NSAIDs). Oral treatment with citral significantly inhibited the neurogenic and inflammatory pain responses induced by intra-plantar injection of formalin. Citral also had prophylactic and therapeutic anti-nociceptive effects against mechanical hyperalgesia in plantar incision surgery, chronic regional pain syndrome, and partial ligation of sciatic nerve models, without producing any significant motor dysfunction. In addition, citral markedly attenuated the pain response induced by intra-plantar injection of glutamate and phorbol 12-myristate 13-acetate (PMA, a protein kinase C activator), as well as by intrathecal (i.t.) injection of ionotropic and metabotropic glutamate receptor agonists (N-methyl-D-aspartic acid [NMDA] and 1-amino-1,3-dicarboxycyclopentane [trans-ACPD], respectively), substance P, and cytokine tumour necrosis factor-α. However, citral potentiated behaviours indicative of pain caused by i.t., but not intra-plantar, injection of a transient receptor potential vanilloid receptor type 1 (TRPV1) agonist. Finally, the anti-nociceptive action of citral was found to involve significant activation of the 5-HT2A serotonin receptor. The effect of citral was accompanied by a gastro-protective effect against NSAID-induced ulcers. Together, these results show the potential of citral as a new drug for the treatment of pain.

  20. A low bending loss multimode fiber transmission system.

    PubMed

    Donlagic, Denis

    2009-11-23

    This paper presents a high bend tolerant multimode optical fiber transmission system that is compatible with standard 50 microm graded index multimode fiber, in terms of achievable bandwidth and interconnectivity losses. When the 10 loops of the proposed bend resistive multimode fiber were wrapped around a cylinder of 1.5 mm radius, bend losses below -0.2 dB were achieved in case of experimentally produced fiber. Furthermore, when the section of the proposed bend resistive fiber was inserted between two sections of a standard 50 microm graded index multimode fiber, the total experimental measured loss proved to be below -0.15 dB. PMID:19997454

  1. The Intersection of Multimodality and Critical Perspective: Multimodality as Subversion

    ERIC Educational Resources Information Center

    Huang, Shin-ying

    2015-01-01

    This study explores the relevance of multimodality to critical media literacy. It is based on the understanding that communication is intrinsically multimodal and multimodal communication is inherently social and ideological. By analysing two English-language learners' multimodal ensembles, the study reports on how multimodality contributes to a…

  2. Combined neuromodulatory interventions in acute experimental pain: assessment of melatonin and non-invasive brain stimulation

    PubMed Central

    da Silva, Nádia Regina Jardim; Laste, Gabriela; Deitos, Alícia; Stefani, Luciana Cadore; Cambraia-Canto, Gustavo; Torres, Iraci L. S.; Brunoni, Andre R.; Fregni, Felipe; Caumo, Wolnei

    2015-01-01

    Transcranial direct current stimulation (tDCS) and melatonin can effectively treat pain. Given their potentially complementary mechanisms of action, their combination could have a synergistic effect. Thus, we tested the hypothesis that compared to the control condition and melatonin alone, tDCS combined with melatonin would have a greater effect on pain modulatory effect, as assessed by quantitative sensory testing (QST) and by the pain level during the Conditioned Pain Modulation (CPM)-task. Furthermore, the combined treatment would have a greater cortical excitability effect as indicated by the transcranial magnetic stimulation (TMS) and on the serum BDNF level. Healthy males (n = 20), (aged 18–40 years), in a blinded, placebo-controlled, crossover, clinical trial, were randomized into three groups: sublingual melatonin (0.25 mg/kg) + a-tDCS, melatonin (0.25 mg/kg) + sham-(s)-tDCS, or sublingual placebo+sham-(s)-tDCS. Anodal stimulation (2 mA, 20 min) was applied over the primary motor cortex. There was a significant difference in the heat pain threshold (°C) for melatonin+a-tDCS vs. placebo+s-tDCS (mean difference: 4.86, 95% confidence interval [CI]: 0.9 to 8.63) and melatonin+s-tDCS vs. placebo+s-tDCS (mean: 5.16, 95% CI: 0.84 to 8.36). There was no difference between melatonin+s-tDCS and melatonin+a-tDCS (mean difference: 0.29, 95% CI: −3.72 to 4.23). The mean change from the baseline on amplitude of motor evocate potential (MEP) was significantly higher in the melatonin+a-tDCS (−19.96% ± 5.2) compared with melatonin+s-tDCS group (−1.36% ± 5.35) and with placebo+s-tDCS group (3.61% ± 10.48), respectively (p < 0.05 for both comparisons). While melatonin alone or combined with a-tDCS did not significantly affect CPM task result, and serum BDNF level. The melatonin effectively reduced pain; however, its association with a-tDCS did not present an additional modulatory effect on acute induced pain. PMID:25873871

  3. Effect of Catechol-O-methyltransferase-gene (COMT) Variants on Experimental and Acute Postoperative Pain in 1,000 Women undergoing Surgery for Breast Cancer

    PubMed Central

    Kambur, Oleg; Kaunisto, Mari A.; Tikkanen, Emmi; Leal, Suzanne M.; Ripatti, Samuli; Kalso, Eija A.

    2016-01-01

    Background Catechol-O-methyltransferase (COMT) metabolizes catecholamines in different tissues. Polymorphisms in COMT gene can attenuate COMT activity and increase sensitivity to pain. Human studies exploring the effect of COMT polymorphisms on pain sensitivity have mostly included small, heterogeneous samples and have ignored several important single nucleotide polymorphisms (SNPs). This study examines the effect of COMT polymorphisms on experimental and postoperative pain phenotypes in a large ethnically homogeneous female patient cohort. Methods Intensity of cold (+2–4°C) and heat (+48°C) pain and tolerance to cold pain were assessed in 1,000 patients scheduled for breast cancer surgery. Acute postoperative pain and oxycodone requirements were recorded. Twenty-two COMT SNPs were genotyped and their association with six pain phenotypes analyzed with linear regression. Results There was no association between any of the tested pain phenotypes and SNP rs4680. The strongest association signals were seen between rs165774 and heat pain intensity as well as rs887200 and cold pain intensity. In both cases, minor allele carriers reported less pain. Neither of these results remained significant after strict multiple testing corrections. When analyzed further, the effect of rs887200 was, however, shown to be significant and consistent throughout the cold pressure test. No evidence of association between the SNPs and postoperative oxycodone consumption was found. Conclusions SNPs rs887200 and rs165774 located in the untranslated regions of the gene had the strongest effects on pain sensitivity. Their effect on pain is described here for the first time. These results should be confirmed in further studies and the potential functional mechanisms of the variants studied. PMID:24343288

  4. Multimode Acoustic Research

    NASA Technical Reports Server (NTRS)

    Barmatz, M.

    1985-01-01

    There is a need for high temperature containerless processing facilities that can efficiently position and manipulate molten samples in the reduced gravity environment of space. The goal of the research is to develop sophisticated high temperature manipulation capabilities such as selection of arbitrary axes rotation and rapid sample cooling. This program will investigate new classes of acoustic levitation in rectangular, cylindrical and spherical geometries. The program tasks include calculating theoretical expressions of the acoustic forces in these geometries for the excitation of up to three acoustic modes (multimodes). These calculations are used to: (1) determine those acoustic modes that produce stable levitation, (2) isolate the levitation and rotation capabilities to produce more than one axis of rotation, and (3) develop methods to translate samples down long tube cylindrical chambers. Experimental levitators will then be constructed to verify the stable levitation and rotation predictions of the models.

  5. Forced-exercise delays neuropathic pain in experimental diabetes: effects on voltage-activated calcium channels.

    PubMed

    Shankarappa, Sahadev A; Piedras-Rentería, Erika S; Stubbs, Evan B

    2011-07-01

    Physical exercise produces a variety of psychophysical effects, including altered pain perception. Elevated levels of centrally produced endorphins or endocannabinoids are implicated as mediators of exercise-induced analgesia. The effect of exercise on the development and persistence of disease-associated acute/chronic pain remains unclear. In this study, we quantified the physiological consequence of forced-exercise on the development of diabetes-associated neuropathic pain. Euglycemic control or streptozotocin (STZ)-induced diabetic adult male rats were subdivided into sedentary or forced-exercised (2-10 weeks, treadmill) subgroups and assessed for changes in tactile responsiveness. Two weeks following STZ-treatment, sedentary rats developed a marked and sustained hypersensitivity to von Frey tactile stimulation. By comparison, STZ-treated diabetic rats undergoing forced-exercise exhibited a 4-week delay in the onset of tactile hypersensitivity that was independent of glucose control. Exercise-facilitated analgesia in diabetic rats was reversed, in a dose-dependent manner, by naloxone. Small-diameter (< 30 μm) DRG neurons harvested from STZ-treated tactile hypersensitive diabetic rats exhibited an enhanced (2.5-fold) rightward (depolarizing) shift in peak high-voltage activated (HVA) Ca(2+) current density with a concomitant appearance of a low-voltage activated (LVA) Ca(2+) current component. LVA Ca(2+) currents present in DRG neurons from hypersensitive diabetic rats exhibited a marked depolarizing shift in steady-state inactivation. Forced-exercise attenuated diabetes-associated changes in HVA Ca(2+) current density while preventing the depolarizing shift in steady-state inactivation of LVA Ca(2+) currents. Forced-exercise markedly delays the onset of diabetes-associated neuropathic pain, in part, by attenuating associated changes in HVA and LVA Ca(2+) channel function within small-diameter DRG neurons possibly by altering opioidergic tone. PMID:21554321

  6. Histology image search using multimodal fusion.

    PubMed

    Caicedo, Juan C; Vanegas, Jorge A; Páez, Fabian; González, Fabio A

    2014-10-01

    This work proposes a histology image indexing strategy based on multimodal representations obtained from the combination of visual features and associated semantic annotations. Both data modalities are complementary information sources for an image retrieval system, since visual features lack explicit semantic information and semantic terms do not usually describe the visual appearance of images. The paper proposes a novel strategy to build a fused image representation using matrix factorization algorithms and data reconstruction principles to generate a set of multimodal features. The methodology can seamlessly recover the multimodal representation of images without semantic annotations, allowing us to index new images using visual features only, and also accepting single example images as queries. Experimental evaluations on three different histology image data sets show that our strategy is a simple, yet effective approach to building multimodal representations for histology image search, and outperforms the response of the popular late fusion approach to combine information. PMID:24820052

  7. Histology image search using multimodal fusion.

    PubMed

    Caicedo, Juan C; Vanegas, Jorge A; Páez, Fabian; González, Fabio A

    2014-10-01

    This work proposes a histology image indexing strategy based on multimodal representations obtained from the combination of visual features and associated semantic annotations. Both data modalities are complementary information sources for an image retrieval system, since visual features lack explicit semantic information and semantic terms do not usually describe the visual appearance of images. The paper proposes a novel strategy to build a fused image representation using matrix factorization algorithms and data reconstruction principles to generate a set of multimodal features. The methodology can seamlessly recover the multimodal representation of images without semantic annotations, allowing us to index new images using visual features only, and also accepting single example images as queries. Experimental evaluations on three different histology image data sets show that our strategy is a simple, yet effective approach to building multimodal representations for histology image search, and outperforms the response of the popular late fusion approach to combine information.

  8. Experimental pain ratings and reactivity of cortisol and soluble tumor necrosis factor-α receptor II following a trial of hypnosis: Results of a randomized controlled pilot study

    PubMed Central

    Goodin, Burel R.; Quinn, Noel B.; Kronfli, Tarek; King, Christopher D.; Page, Gayle G.; Haythornthwaite, Jennifer A.; Edwards, Robert R.; Stapleton, Laura M.; McGuire, Lynanne

    2011-01-01

    Objective Current evidence supports the efficacy of hypnosis for reducing the pain associated with experimental stimulation and various acute and chronic conditions; however, the mechanisms explaining how hypnosis exerts its effects remain less clear. The hypothalamic-pituitary-adrenal (HPA) axis and pro-inflammatory cytokines represent potential targets for investigation given their purported roles in the perpetuation of painful conditions; yet, no clinical trials have thus far examined the influence of hypnosis on these mechanisms. Design Healthy participants, highly susceptible to the effects of hypnosis, were randomized to either a hypnosis intervention or a no-intervention control. Using a cold pressor task, assessments of pain intensity and pain unpleasantness were collected prior to the intervention (Pre) and following the intervention (Post) along with pain-provoked changes in salivary cortisol and the soluble receptor of tumor necrosis factor-α (sTNFαRII). Results Compared to the no-intervention control, data analyses revealed that hypnosis significantly reduced pain intensity and pain unpleasantness. Hypnosis was not significantly associated with suppression of cortisol or sTNFαRII reactivity to acute pain from Pre to Post; however, the effect sizes for these associations were medium-sized. Conclusions Overall, the findings from this randomized controlled pilot study support the importance of a future large-scale study on the effects of hypnosis for modulating pain-related changes of the HPA axis and pro-inflammatory cytokines. PMID:22233394

  9. Blocking of TRPV-1 in the parodontium relieves orthodontic pain by inhibiting the expression of TRPV-1 in the trigeminal ganglion during experimental tooth movement in rats.

    PubMed

    Gao, Yunan; Liu, Yingfei; Zhu, Kun; Zhang, Zhichao; Qiao, Hu; Lu, Zhen; Zhong, Tianyu; Liu, Yong; Zhou, Hong

    2016-08-15

    Orthodontic pain has confused the orthodontics for a long time, and recent research demonstrated that transient receptor potential vanilloid type 1 (TRPV1) had crucial functions in transduction of painful stimuli. The present research investigated the analgesia effects of the blocking TRPV1 on orthodontic pain during experimental tooth movement. Under challenge with experimental tooth movement, the expression of TRPV1 in the parodontium was increased in a time-dependent and force-dependent manner. And treatment with selective TRPV1 antagonist AMG-9810 in the parodontium reduced the expression of TRPV1 in the trigeminal ganglion (TG) and decreased the secretion of IL-1β in the gingival crevicular fluid. Furthermore, AMG-9810 could relieve orthodontic pain arising from experimental tooth movement in rats. We suggest that TRPV1 both in the parodontium and trigeminal ganglion are involved in orthodontic pain, and TRPV1 in the parodontium influence on orthodontic pain through reducing the expression of TRPV1 in trigeminal ganglion. Our finding may help to develop strategies for relieving orthodontic pain after orthodontics. PMID:27267133

  10. Changes in Disability, Physical/Mental Health States and Quality of Life during an 8-Week Multimodal Physiotherapy Programme in Patients with Chronic Non-Specific Neck Pain: A Prospective Cohort Study

    PubMed Central

    Cuesta-Vargas, Antonio Ignacio; González-Sánchez, Manuel

    2015-01-01

    Aim The aim of this study was to analyse the effect of an 8-week multimodal physiotherapy programme (MPP), integrating physical land-based therapeutic exercise (TE), adapted swimming and health education, as a treatment for patients with chronic non-specific neck pain (CNSNP), on disability, general health/mental states and quality of life. Methods 175 CNSNP patients from a community-based centre were recruited to participate in this prospective study. Intervention: 60-minute session (30 minutes of land-based exercise dedicated to improving mobility, motor control, resistance and strengthening of the neck muscles, and 30 minutes of adapted swimming with aerobic exercise keeping a neutral neck position using a snorkel). Health education was provided using a decalogue on CNSNP and constant repetition of brief advice by the physiotherapist during the supervision of the exercises in each session. Study outcomes: primary: disability (Neck Disability Index); secondary: physical and mental health states and quality of life of patients (SF-12 and EuroQoL-5D respectively). Differences between baseline data and that at the 8-week follow-up were calculated for all outcome variables. Results Disability showed a significant improvement of 24.6% from a mean (SD) of 28.2 (13.08) at baseline to 16.88 (11.62) at the end of the 8-week intervention. All secondary outcome variables were observed to show significant, clinically relevant improvements with increase ranges between 13.0% and 16.3% from a mean of 0.70 (0.2) at baseline to 0.83 (0.2), for EuroQoL-5D, and from a mean of 40.6 (12.7) at baseline to 56.9 (9.5), for mental health state, at the end of the 8-week intervention. Conclusion After 8 weeks of a MPP that integrated land-based physical TE, health education and adapted swimming, clinically-relevant and statistically-significant improvements were observed for disability, physical and mental health states and quality of life in patients who suffer CNSNP. The clinical

  11. Association between sensitisation and pain-related behaviours in an experimental canine model of osteoarthritis.

    PubMed

    Rialland, Pascale; Otis, Colombe; Moreau, Maxim; Pelletier, Jean-Pierre; Martel-Pelletier, Johanne; Beaudry, Francis; Del Castillo, Jerome R E; Bertaim, Thierry; Gauvin, Dominique; Troncy, Eric

    2014-10-01

    Evaluation of nociceptive sensitisation in canine osteoarthritis studies has been poorly reported, or even related to other clinical symptoms. In 16 dogs, peak vertical force (PVF), subjective pain assessment using 3 scales, sympathetic stress response with electrodermal activity (EDA) measurement, and behavioural changes with video analysis and telemetered motor activity were quantified at baseline (D-7), and 28 and 56 days post transection of the cranial cruciate ligament. As markers of central sensitisation, selected spinal cord biomarkers (substance P and transthyretin) were quantified at D56. Electrical withdrawal thresholds on the stifle and the tail were measured as indicative of peripheral and central quantitative sensory testing (QST) sensitisation, respectively. The effects of vehicle administration (n=8) were compared with tiludronate (2mg/kg subcutaneously, q2 week, starting at D0) administration. Generalized estimated equations tested the association between the behavioural and physiological methods and QST sensitisation, and therefore the sensitivity of the methods for detecting treatment efficacy. Compared to tiludronate, at D56, vehicle-treated dogs had increased spinal substance P (P=0.01), concomitant decreased transthyretin (P=0.02), and (compared to baseline) demonstrated peripheral and central QST sensitisation, which was not present for tiludronate. Only PVF, the spontaneous behaviour "walking with full weight-bearing," and EDA were associated with occurrence of QST sensitisation and indicated significant tiludronate analgesic efficacy after inclusion of central QST sensitisation as a predictor variable in the statistical model. This study establishes the strong interest to implement QST as a predictor of canine osteoarthritis pain symptoms explained by pain sensitisation.

  12. Treatment of myofascial pain.

    PubMed

    Desai, Mehul J; Bean, Matthew C; Heckman, Thomas W; Jayaseelan, Dhinu; Moats, Nick; Nava, Andrew

    2013-01-01

    SUMMARY The objective of this article was to perform a narrative review regarding the treatment of myofascial pain syndrome and to provide clinicians with treatment recommendations. This paper reviews the efficacy of various myofascial pain syndrome treatment modalities, including pharmacological therapy, injection-based therapies and physical therapy interventions. Outcomes evaluated included pain (visual analog scale), pain pressure threshold and range of motion. The evidence found significant benefit with multiple treatments, including diclofenac patch, thiocolchicoside and lidocaine patches. Trigger point injections, ischemic compression therapy, transcutaneous electrical nerve stimulation, spray and stretch, and myofascial release were also efficacious. The authors recommend focusing on treating underlying pathologies, including spinal conditions, postural abnormalities and underlying behavioral issues. To achieve maximum pain reduction and improve function, we recommend physicians approach myofascial pain syndrome with a multimodal plan, which includes a combination of pharmacologic therapies, various physical therapeutic modalities and injection therapies.

  13. Treatment of myofascial pain.

    PubMed

    Desai, Mehul J; Bean, Matthew C; Heckman, Thomas W; Jayaseelan, Dhinu; Moats, Nick; Nava, Andrew

    2013-01-01

    SUMMARY The objective of this article was to perform a narrative review regarding the treatment of myofascial pain syndrome and to provide clinicians with treatment recommendations. This paper reviews the efficacy of various myofascial pain syndrome treatment modalities, including pharmacological therapy, injection-based therapies and physical therapy interventions. Outcomes evaluated included pain (visual analog scale), pain pressure threshold and range of motion. The evidence found significant benefit with multiple treatments, including diclofenac patch, thiocolchicoside and lidocaine patches. Trigger point injections, ischemic compression therapy, transcutaneous electrical nerve stimulation, spray and stretch, and myofascial release were also efficacious. The authors recommend focusing on treating underlying pathologies, including spinal conditions, postural abnormalities and underlying behavioral issues. To achieve maximum pain reduction and improve function, we recommend physicians approach myofascial pain syndrome with a multimodal plan, which includes a combination of pharmacologic therapies, various physical therapeutic modalities and injection therapies. PMID:24645933

  14. Antihyperalgesic Effect of Hesperidin Improves with Diosmin in Experimental Neuropathic Pain

    PubMed Central

    Pellicer, Francisco; López-Muñoz, Francisco J.

    2016-01-01

    Neuropathic pain is caused by a primary lesion, dysfunction, or transitory perturbation in the peripheral or central nervous system. In this study, we investigated the hesperidin antihyperalgesic effects alone or combined with diosmin in a model of neuropathic pain to corroborate a possible synergistic antinociceptive activity. Mechanical and thermal hyperalgesia were assessed in the aesthesiometer and plantar tests, respectively, after chronic constriction injury (CCI) model in rats receiving hesperidin (HS, 5 doses from 10 to 1000 mg/kg) alone or combined with diosmin (DS, 10 and 100 mg/kg) in comparison to gabapentin (31.6 mg/kg). UHPLC-MS analysis of cerebral samples was used to recognize the central concentrations of these flavonoids. Participation of different receptors was also investigated in the presence of haloperidol, bicuculline, and naloxone antagonists. Acute hesperidin administration significantly decreased mechanical and thermal hyperalgesia in CCI rats. Antihyperalgesic response of hesperidin, improved by a combination with diosmin (DS10/HS100) in both stimuli, was blockaded by haloperidol, bicuculline, and naloxone, but not WAY100635, antagonists. Both flavonoids were detected in brain samples. In conclusion, hesperidin alone and combined with diosmin produces antihyperalgesic response in the CCI model in rats. Antihyperalgesic effect of DS10/HS100 combination involves central activity partially modulated by D2, GABAA, and opioids, but not by 5-HT1A, receptors. PMID:27672659

  15. Antihyperalgesic Effect of Hesperidin Improves with Diosmin in Experimental Neuropathic Pain

    PubMed Central

    Pellicer, Francisco; López-Muñoz, Francisco J.

    2016-01-01

    Neuropathic pain is caused by a primary lesion, dysfunction, or transitory perturbation in the peripheral or central nervous system. In this study, we investigated the hesperidin antihyperalgesic effects alone or combined with diosmin in a model of neuropathic pain to corroborate a possible synergistic antinociceptive activity. Mechanical and thermal hyperalgesia were assessed in the aesthesiometer and plantar tests, respectively, after chronic constriction injury (CCI) model in rats receiving hesperidin (HS, 5 doses from 10 to 1000 mg/kg) alone or combined with diosmin (DS, 10 and 100 mg/kg) in comparison to gabapentin (31.6 mg/kg). UHPLC-MS analysis of cerebral samples was used to recognize the central concentrations of these flavonoids. Participation of different receptors was also investigated in the presence of haloperidol, bicuculline, and naloxone antagonists. Acute hesperidin administration significantly decreased mechanical and thermal hyperalgesia in CCI rats. Antihyperalgesic response of hesperidin, improved by a combination with diosmin (DS10/HS100) in both stimuli, was blockaded by haloperidol, bicuculline, and naloxone, but not WAY100635, antagonists. Both flavonoids were detected in brain samples. In conclusion, hesperidin alone and combined with diosmin produces antihyperalgesic response in the CCI model in rats. Antihyperalgesic effect of DS10/HS100 combination involves central activity partially modulated by D2, GABAA, and opioids, but not by 5-HT1A, receptors.

  16. Analgesic effects of transcutaneous electrical nerve stimulation and interferential current on experimental ischemic pain models: frequencies of 50 hz and 100 hz.

    PubMed

    Bae, Young-Hyeon; Lee, Suk Min

    2014-12-01

    [Purpose] This study compared the analgesic effects of transcutaneous electrical nerve stimulation (TENS) and interferential currents (IFC) on induced ischemic pain in healthy volunteers. [Subjects] The subjects were 36 volunteers (18 male, 18 female) without known pathology that could cause pain. Their mean age was 24.5±2.2 years. [Methods] A single-blind and parallel-group method was used. Subjects were randomly allocated to receive each 50 Hz TENS, 50 Hz IFC, 100 Hz TENS, and 100 Hz IFC. This study experimentally induced ischemic pain in otherwise pain-free subjects using a modified version of the submaximal effort tourniquet technique. Subjects completed twelve cycles of the ischemic-induced pain test. The primary outcome measure was the change in self-reported of pain intensity during one of four possible treatments. [Results] There were significant effects for Time, which were attributed to a significant reduction in pain intensity for all groups. There were no significant effects for groups or group-time interaction. The 50 Hz IFC treatment was more comfortable than the other treatments in the present study, and it is likely to be better accepted and tolerated by patients. [Conclusion] We conclude that there were no differences in the analgesic effects of the four treatments under the present experimental conditions. The 50 Hz IFC treatment is more comfortable than the other treatments.

  17. Multimode waveguide components for millimeter-wave integrated circuits

    NASA Astrophysics Data System (ADS)

    Bhooshan, S.; Mittra, R.

    1980-01-01

    In this paper, we report the results of an investigation of multimode, planar dielectric waveguides for integrated circuit application at millimeter wavelengths. Two multimode devices have been fabricated and tested using the inverted strip guide (ISG), and a comparison between the theoretical and experimental results is given.

  18. Multimodal Learning Clubs

    ERIC Educational Resources Information Center

    Casey, Heather

    2012-01-01

    Multimodal learning clubs link principles of motivation and engagement with 21st century technological tools and texts to support content area learning. The author describes how a sixth grade health teacher and his class incorporated multimodal learning clubs into a unit of study on human body systems. The students worked collaboratively online…

  19. The relationship of adult attachment to emotion, catastrophizing, control, threshold and tolerance, in experimentally-induced pain.

    PubMed

    Meredith, Pamela J; Strong, Jenny; Feeney, Judith A

    2006-01-01

    Although insecure attachment has been associated with a range of variables linked with problematic adjustment to chronic pain, the causal direction of these relationships remains unclear. Adult attachment style is, theoretically, developmentally antecedent to cognitions, emotions and behaviours (and might therefore be expected to contribute to maladjustment). It can also be argued, however, that the experience of chronic pain increases attachment insecurity. This project examined this issue by determining associations between adult attachment characteristics, collected prior to an acute (coldpressor) pain experience, and a range of emotional, cognitive, pain tolerance, intensity and threshold variables collected during and after the coldpressor task. A convenience sample of 58 participants with no history of chronic pain was recruited. Results demonstrated that attachment anxiety was associated with lower pain thresholds; more stress, depression, and catastrophizing; diminished perceptions of control over pain; and diminished ability to decrease pain. Conversely, secure attachment was linked with lower levels of depression and catastrophizing, and more control over pain. Of particular interest were findings that attachment style moderated the effects of pain intensity on the tendency to catastrophize, such that insecurely attached individuals were more likely to catastrophize when reporting high pain intensity. This is the first study to link attachment with perceptions of pain in a pain-free sample. These findings cast anxious attachment as a vulnerability factor for chronic pain following acute episodes of pain, while secure attachment may provide more resilience.

  20. Chronic Pain

    MedlinePlus

    ... adults. Common chronic pain complaints include headache, low back pain, cancer pain, arthritis pain, neurogenic pain (pain resulting ... Institute of Neurological Disorders and Stroke (NINDS). Low Back Pain Fact Sheet Back Pain information sheet compiled by ...

  1. Postoperative Pain Control

    PubMed Central

    Garimella, Veerabhadram; Cellini, Christina

    2013-01-01

    The effective relief of pain is of the utmost importance to anyone treating patients undergoing surgery. Pain relief has significant physiological benefits; hence, monitoring of pain relief is increasingly becoming an important postoperative quality measure. The goal for postoperative pain management is to reduce or eliminate pain and discomfort with a minimum of side effects. Various agents (opioid vs. nonopioid), routes (oral, intravenous, neuraxial, regional) and modes (patient controlled vs. “as needed”) for the treatment of postoperative pain exist. Although traditionally the mainstay of postoperative analgesia is opioid based, increasingly more evidence exists to support a multimodal approach with the intent to reduce opioid side effects (such as nausea and ileus) and improve pain scores. Enhanced recovery protocols to reduce length of stay in colorectal surgery are becoming more prevalent and include multimodal opioid sparing regimens as a critical component. Familiarity with the efficacy of available agents and routes of administration is important to tailor the postoperative regimen to the needs of the individual patient. PMID:24436674

  2. Visualization of multimodal polymer-shelled contrast agents using ultrasound contrast sequences: an experimental study in a tissue mimicking flow phantom

    PubMed Central

    2013-01-01

    Background A multimodal polymer-shelled contrast agent (CA) with target specific potential was recently developed and tested for its acoustic properties in a single element transducer setup. Since the developed polymeric CA has different chemical composition than the commercially available CAs, there is an interest to study its acoustic response when using clinical ultrasound systems. The aim of this study was therefore to investigate the acoustic response by studying the visualization capability and shadowing effect of three polymer-shelled CAs when using optimized sequences for contrast imaging. Methods The acoustic response of three types of the multimodal CA was evaluated in a tissue mimicking flow phantom setup by measuring contrast to tissue ratio (CTR) and acoustic shadowing using five image sequences optimized for contrast imaging. The measurements were performed over a mechanical index (MI) range of 0.2-1.2 at three CA concentrations (106, 105, 104 microbubbles/ml). Results The CTR-values were found to vary with the applied contrast sequence, MI and CA. The highest CTR-values were obtained when a contrast sequence optimized for higher MI imaging was used. At a CA concentration of 106 microbubbles/ml, acoustic shadowing was observed for all contrast sequences and CAs. Conclusions The CAs showed the potential to enhance ultrasound images generated by available contrast sequences. A CA concentration of 106 MBs/ml implies a non-linear relation between MB concentration and image intensity. PMID:23987142

  3. Biochemical and pharmacological assessment of MAP-kinase signaling along pain pathways in experimental rodent models: a potential tool for the discovery of novel antinociceptive therapeutics.

    PubMed

    Edelmayer, Rebecca M; Brederson, Jill-Desiree; Jarvis, Michael F; Bitner, Robert S

    2014-02-01

    Injury to the peripheral or central nervous system can induce changes within the nervous tissues that promote a state of sensitization that may underlie conditions of pathological chronic pain. A key biochemical event in the initiation and maintenance of peripheral and central neuronal sensitization associated with chronic pain is the phosphorylation and subsequent activation of mitogen-activated protein kinases (MAPKs) and immediate early gene transcription factors, in particular cAMP-response element binding protein (CREB). In this commentary we review the preclinical data that describe anatomical and mechanistic aspects of nociceptive-induced signaling along nociceptive pathways including peripheral cutaneous axons, the dorsal root ganglia, spinal cord dorsal horn and cerebral cortex. In addition to the regional manifestation of nociceptive signaling, investigations have attempted to elucidate the cellular origin of biochemical nociceptive processing in which communication, i.e. cross-talk between neurons and glia is viewed as an essential component of pathogenic pain development. Here, we outline a research strategy by which nociceptive-induced cellular signaling in experimental pain models, specifically MAPK and CREB phosphorylation can be utilized to provide mechanistic insight into drug-target interaction along the nociceptive pathways. We describe a series of studies using nociceptive inflammatory and neuropathic pain models to investigate the effects of known pain therapeutics on nociceptive-induced biochemical signaling and present this as a complementary research strategy for assessing antinociceptive activity useful in the preclinical development of novel pain therapeutics.

  4. A single-blind placebo-controlled investigation into the analgesic effects of interferential currents on experimentally induced ischaemic pain in healthy subjects.

    PubMed

    Johnson, Mark I; Tabasam, Ghazala

    2002-05-01

    The aim of this single-blind placebo-controlled study was to examine the analgesic effects of interferential currents (IFC) on experimentally induced ischaemic pain. Ischaemic pain was induced using the submaximal effort tourniquet technique (SETT) and pain intensity was recorded using a visual analogue scale at 1-min intervals was used as the primary outcome measure. Following baseline recordings 30 healthy volunteers received either active IFC, sham IFC, or no treatment (10 subjects per group). Data were analysed by calculating the mean change in pain intensity at each 1-min interval by subtracting data during treatment from the baseline data. IFC was administered throughout the duration of the ischaemic pain test via four electrodes (quadripolar application) on the forearm. Active IFC delivered electrical currents at a 'strong but comfortable' intensity. A 'dummy' stimulator that delivered no current was used as sham IFC. Subjects in the no treatment control group were informed that the IFC device was not switched on. There were significant effects for Groups (P=0.04) which were attributed to a significant reduction in pain intensity for the IFC group when compared with sham and no-treatment control (P< or =0.05). There were no significant effects for Time (P=0.69) or Group-Time interaction (P=0.45). In conclusion, IFC produced significantly greater analgesia than sham and no-treatment control groups under the present experimental conditions.

  5. Increased pain intensity is associated with greater verbal communication difficulty and increased production of speech and co-speech gestures.

    PubMed

    Rowbotham, Samantha; Wardy, April J; Lloyd, Donna M; Wearden, Alison; Holler, Judith

    2014-01-01

    Effective pain communication is essential if adequate treatment and support are to be provided. Pain communication is often multimodal, with sufferers utilising speech, nonverbal behaviours (such as facial expressions), and co-speech gestures (bodily movements, primarily of the hands and arms that accompany speech and can convey semantic information) to communicate their experience. Research suggests that the production of nonverbal pain behaviours is positively associated with pain intensity, but it is not known whether this is also the case for speech and co-speech gestures. The present study explored whether increased pain intensity is associated with greater speech and gesture production during face-to-face communication about acute, experimental pain. Participants (N = 26) were exposed to experimentally elicited pressure pain to the fingernail bed at high and low intensities and took part in video-recorded semi-structured interviews. Despite rating more intense pain as more difficult to communicate (t(25)  = 2.21, p =  .037), participants produced significantly longer verbal pain descriptions and more co-speech gestures in the high intensity pain condition (Words: t(25)  = 3.57, p  = .001; Gestures: t(25)  = 3.66, p =  .001). This suggests that spoken and gestural communication about pain is enhanced when pain is more intense. Thus, in addition to conveying detailed semantic information about pain, speech and co-speech gestures may provide a cue to pain intensity, with implications for the treatment and support received by pain sufferers. Future work should consider whether these findings are applicable within the context of clinical interactions about pain. PMID:25343486

  6. Pain in systemic sclerosis.

    PubMed

    Stisi, S; Sarzi-Puttini, P; Benucci, M; Biasi, G; Bellissimo, S; Talotta, R; Atzeni, F

    2014-01-01

    Chronic pain is a healthcare problem that significantly affects the mental health, and the professional and private life of patients. It can complicate many disorders and represents a common symptom of rheumatologic diseases, but the data on its prevalence is still limited. Pain is a ubiquitous problem in systemic sclerosis (SSc). SSc-related pain has been studied on the basis of biomedical models and is considered a symptom caused by the disease activity or previous tissue damage. Effective pain management is a primary goal of the treatment strategy, although this symptom in SSc has not yet been investigated in detail. However, these patients do not all respond adequately to pharmacological pain therapies, therefore in these cases a multimodal approach needs to be adopted. PMID:24938196

  7. Acute pain medicine in anesthesiology

    PubMed Central

    Munro, Anastacia P.; Tighe, Patrick J.

    2013-01-01

    The American Academy of Pain Medicine and the American Society for Regional Anesthesia have recently focused on the evolving practice of acute pain medicine. There is increasing recognition that the scope and practice of acute pain therapies must extend beyond the subacute pain phase to include pre-pain and pre-intervention risk stratification, resident and fellow education in regional anesthesia and multimodal analgesia, as well as a deeper understanding of the pathophysiologic mechanisms that are integral to the variability observed among individual responses to nociception. Acute pain medicine is also being established as a vital component of successful systems-level acute pain management programs, inpatient cost containment, and patient satisfaction scores. In this review, we discuss the evolution and practice of acute pain medicine and we aim to facilitate further discussion on the evolution and advancement of this field as a subspecialty of anesthesiology. PMID:24381730

  8. [Multimodal therapy concepts for failed back surgery syndrome].

    PubMed

    Casser, Hans-Raimund

    2016-09-01

    Failed back surgery syndrome (FBSS) is a frequent complication (15-40 %) of lumbar disc surgery and is rarely successfully treated by surgery with the exception of a re-prolapse associated with radicular pain. Multimodal pain treatment, however, is indicated by a lack of pathoanatomical correlates, unclear cause and psychosocial risk factors.This review describes a standardized non-operative treatment starting with broad interdisciplinary clarification by medical, psychological and physiotherapeutic means (assessment).If the conditions for multimodal pain therapy are met, the OPS 8‑918-procedure can be applied to avoid chronic developing pain. In doing so, the already issued quality standards and guidelines for documentation should be respected. PMID:27514828

  9. Multimode Directional Coupler

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N. (Inventor); Wintucky, Edwin G. (Inventor)

    2016-01-01

    A multimode directional coupler is provided. In some embodiments, the multimode directional coupler is configured to receive a primary signal and a secondary signal at a first port of a primary waveguide. The primary signal is configured to propagate through the primary waveguide and be outputted at a second port of the primary waveguide. The multimode directional coupler also includes a secondary waveguide configured to couple the secondary signal from the primary waveguide with no coupling of the primary signal into the secondary waveguide. The secondary signal is configured to propagate through the secondary waveguide and be outputted from a port of the secondary waveguide.

  10. Metawidgets in the multimodal interface

    SciTech Connect

    Blattner, M.M. Anderson Cancer Center, Houston, TX ); Glinert, E.P.; Jorge, J.A.; Ormsby, G.R. . Dept. of Computer Science)

    1991-01-01

    We analyze two intertwined and fundamental issues concerning computer-to-human communication in the multimodal interfaces: the interplay between sound and graphics, and the role of object persistence. Our observations lead us to introduce metawidgets as abstract entities capable of manifesting themselves to users as image, as sound, or as various combinations and/or sequences of the two media. We show examples of metawidgets in action, and discuss mechanisms for choosing among alternative media for metawidget instantiation. Finally, we describe a couple of experimental microworlds we have implemented to test out some of our ideas. 17 refs., 7 figs.

  11. Neuropathic pain with features of complex regional syndrome in the upper extremity after herpes zoster.

    PubMed

    Giménez-Milà, Marc; Busquets, Carme; Ojeda, Antonio; Faulí, Adela; Moreno, Luis Alfonso; Videla, Sebastian

    2014-02-01

    We report a case of a 73-year-old female who developed unbearable neuropathic pain after a herpes zoster episode. The pain persisted and could not be controlled despite multimodal analgesia. In addition to postherpetic neuralgia, myelitis and complex regional pain syndrome were diagnosed during the evolution of neuropathic pain. This complex neuropathic pain was resolved after sympathetic ganglion block.

  12. Neck pain

    PubMed Central

    2008-01-01

    Introduction Non-specific neck pain has a postural or mechanical basis and affects about two thirds of people at some stage, especially in middle age. Acute neck pain resolves within days or weeks, but may become chronic in about 10% of people. Whiplash injuries follow sudden acceleration–deceleration of the neck, such as in road traffic or sporting accidents. Up to 40% of people continue to report symptoms 15 years after the accident, although this varies between countries. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments for people with non-specific neck pain without severe neurological deficit? What are the effects of treatments for acute whiplash injury? What are the effects of treatments for chronic whiplash injury? What are the effects of treatments for neck pain with radiculopathy? We searched: Medline, Embase, The Cochrane Library, and other important databases up to May 2007 (BMJ Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 91 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of the evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: acupuncture, biofeedback, drug treatments (analgesics, antidepressants, epidural steroid injections, muscle relaxants, non-steroidal anti-inflammatory drugs [NSAIDs]), early mobilisation, early return to normal activity, exercise, heat or cold, manipulation (alone or plus exercise), mobilisation, multimodal treatment, patient education, percutaneous radiofrequency neurotomy

  13. Video genre classification using multimodal features

    NASA Astrophysics Data System (ADS)

    Jin, Sung Ho; Bae, Tae Meon; Choo, Jin Ho; Ro, Yong Man

    2003-12-01

    We propose a video genre classification method using multimodal features. The proposed method is applied for the preprocessing of automatic video summarization or the retrieval and classification of broadcasting video contents. Through a statistical analysis of low-level and middle-level audio-visual features in video, the proposed method can achieve good performance in classifying several broadcasting genres such as cartoon, drama, music video, news, and sports. In this paper, we adopt MPEG-7 audio-visual descriptors as multimodal features of video contents and evaluate the performance of the classification by feeding the features into a decision tree-based classifier which is trained by CART. The experimental results show that the proposed method can recognize several broadcasting video genres with a high accuracy and the classification performance with multimodal features is superior to the one with unimodal features in the genre classification.

  14. Multimodal imaging of cutaneous wound tissue

    NASA Astrophysics Data System (ADS)

    Zhang, Shiwu; Gnyawali, Surya; Huang, Jiwei; Ren, Wenqi; Gordillo, Gayle; Sen, Chandan K.; Xu, Ronald

    2015-01-01

    Quantitative assessment of wound tissue ischemia, perfusion, and inflammation provides critical information for appropriate detection, staging, and treatment of chronic wounds. However, few methods are available for simultaneous assessment of these tissue parameters in a noninvasive and quantitative fashion. We integrated hyperspectral, laser speckle, and thermographic imaging modalities in a single-experimental setup for multimodal assessment of tissue oxygenation, perfusion, and inflammation characteristics. Algorithms were developed for appropriate coregistration between wound images acquired by different imaging modalities at different times. The multimodal wound imaging system was validated in an occlusion experiment, where oxygenation and perfusion maps of a healthy subject's upper extremity were continuously monitored during a postocclusive reactive hyperemia procedure and compared with standard measurements. The system was also tested in a clinical trial where a wound of three millimeters in diameter was introduced on a healthy subject's lower extremity and the healing process was continuously monitored. Our in vivo experiments demonstrated the clinical feasibility of multimodal cutaneous wound imaging.

  15. Differences in pain-related fear acquisition and generalization: an experimental study comparing patients with fibromyalgia and healthy controls.

    PubMed

    Meulders, Ann; Jans, Anne; Vlaeyen, Johan W S

    2015-01-01

    Anomalies in fear learning, such as failure to inhibit fear to safe stimuli, lead to sustained anxiety, which in turn may augment pain. In the same vein, stimulus generalization is adaptive as it enables individuals to extrapolate the predictive value of 1 stimulus to similar stimuli. However, when fear spreads in an unbridled way to novel technically safe stimuli, stimulus generalization becomes maladaptive and may lead to dysfunctional avoidance behaviors and culminate in severe pain disability. In a voluntary movement conditioning paradigm, we compared the acquisition and generalization of pain-related fear in patients with fibromyalgia (FM) and healthy controls. During acquisition, participants received predictable pain in 1 context (ie, 1 movement predicts pain, whereas another does not), and unpredictable pain in another (ie, pain never contingent upon movement). Fear generalization to novel movements (resembling the original painful or nonpainful movement) was tested in both contexts. Results indicated that the FM group showed slower differential acquisition of pain-related fear in the predictable context, and more contextual pain-related fear in the unpredictable context. Fear of movement-related pain spreads selectively to novel movements similar to the original painful movement, and not to those resembling the nonpainful movement in the healthy controls, but nondifferential fear generalization was observed in FM. As expected, in the unpredictable context, we also observed nondifferential fear generalization; this effect was more pronounced in FM. Given the status of overgeneralization as a plausible transdiagnostic pathogenic marker, we believe that this research might increase our knowledge about pathogenesis of musculoskeletal widespread pain. PMID:25599307

  16. Differences in pain-related fear acquisition and generalization: an experimental study comparing patients with fibromyalgia and healthy controls.

    PubMed

    Meulders, Ann; Jans, Anne; Vlaeyen, Johan W S

    2015-01-01

    Anomalies in fear learning, such as failure to inhibit fear to safe stimuli, lead to sustained anxiety, which in turn may augment pain. In the same vein, stimulus generalization is adaptive as it enables individuals to extrapolate the predictive value of 1 stimulus to similar stimuli. However, when fear spreads in an unbridled way to novel technically safe stimuli, stimulus generalization becomes maladaptive and may lead to dysfunctional avoidance behaviors and culminate in severe pain disability. In a voluntary movement conditioning paradigm, we compared the acquisition and generalization of pain-related fear in patients with fibromyalgia (FM) and healthy controls. During acquisition, participants received predictable pain in 1 context (ie, 1 movement predicts pain, whereas another does not), and unpredictable pain in another (ie, pain never contingent upon movement). Fear generalization to novel movements (resembling the original painful or nonpainful movement) was tested in both contexts. Results indicated that the FM group showed slower differential acquisition of pain-related fear in the predictable context, and more contextual pain-related fear in the unpredictable context. Fear of movement-related pain spreads selectively to novel movements similar to the original painful movement, and not to those resembling the nonpainful movement in the healthy controls, but nondifferential fear generalization was observed in FM. As expected, in the unpredictable context, we also observed nondifferential fear generalization; this effect was more pronounced in FM. Given the status of overgeneralization as a plausible transdiagnostic pathogenic marker, we believe that this research might increase our knowledge about pathogenesis of musculoskeletal widespread pain.

  17. Chronic Pain in Neurosurgery.

    PubMed

    Grodofsky, Samuel

    2016-09-01

    This review includes a summary of contemporary theories of pain processing and advocates a multimodal analgesia approach for providing perioperative care. A summary of various medication classes and anesthetic techniques is provided that highlights evidence emerging from neurosurgical literature. This summary covers opioid management, acetaminophen, nonsteroidal antiinflammatories, ketamine, lidocaine, dexmedetomidine, corticosteroids, gabapentin, and regional anesthesia for neurosurgery. At present, there is not enough investigation into these areas to describe best practices for treating or preventing chronic pain in neurosurgery; but providers can identify a wider range of options available to personalize perioperative care strategies. PMID:27521193

  18. Pain in Cancer Survivors

    PubMed Central

    Glare, Paul A.; Davies, Pamela S.; Finlay, Esmé; Gulati, Amitabh; Lemanne, Dawn; Moryl, Natalie; Oeffinger, Kevin C.; Paice, Judith A.; Stubblefield, Michael D.; Syrjala, Karen L.

    2014-01-01

    Pain is a common problem in cancer survivors, especially in the first few years after treatment. In the longer term, approximately 5% to 10% of survivors have chronic severe pain that interferes with functioning. The prevalence is much higher in certain subpopulations, such as breast cancer survivors. All cancer treatment modalities have the potential to cause pain. Currently, the approach to managing pain in cancer survivors is similar to that for chronic cancer-related pain, pharmacotherapy being the principal treatment modality. Although it may be appropriate to continue strong opioids in survivors with moderate to severe pain, most pain problems in cancer survivors will not require them. Moreover, because more than 40% of cancer survivors now live longer than 10 years, there is growing concern about the long-term adverse effects of opioids and the risks of misuse, abuse, and overdose in the nonpatient population. As with chronic nonmalignant pain, multimodal interventions that incorporate nonpharmacologic therapies should be part of the treatment strategy for pain in cancer survivors, prescribed with the aim of restoring functionality, not just providing comfort. For patients with complex pain issues, multidisciplinary programs should be used, if available. New or worsening pain in a cancer survivor must be evaluated to determine whether the cause is recurrent disease or a second malignancy. This article focuses on patients with a history of cancer who are beyond the acute diagnosis and treatment phase and on common treatment-related pain etiologies. The benefits and harms of the various pharmacologic and nonpharmacologic options for pain management in this setting are reviewed. PMID:24799477

  19. Multimodal sequence learning.

    PubMed

    Kemény, Ferenc; Meier, Beat

    2016-02-01

    While sequence learning research models complex phenomena, previous studies have mostly focused on unimodal sequences. The goal of the current experiment is to put implicit sequence learning into a multimodal context: to test whether it can operate across different modalities. We used the Task Sequence Learning paradigm to test whether sequence learning varies across modalities, and whether participants are able to learn multimodal sequences. Our results show that implicit sequence learning is very similar regardless of the source modality. However, the presence of correlated task and response sequences was required for learning to take place. The experiment provides new evidence for implicit sequence learning of abstract conceptual representations. In general, the results suggest that correlated sequences are necessary for implicit sequence learning to occur. Moreover, they show that elements from different modalities can be automatically integrated into one unitary multimodal sequence.

  20. A comparison of the clinical and experimental characteristics of four acute surgical pain models: dental extraction, bunionectomy, joint replacement, and soft tissue surgery.

    PubMed

    Singla, Neil K; Desjardins, Paul J; Chang, Phoebe D

    2014-03-01

    When a clinical trial of an analgesic produces a negative finding, it is important to consider the influence (if any) of experimental error on the validity of that result. Although efforts to identify and minimize experimental error in chronic pain investigations have begun in earnest, less work has been performed on the optimization of acute pain methodology. Of the acute surgical pain methodology articles that have been published over the last decade, almost all focus on either the dental or bunion model. Analgesics are typically evaluated in a variety of surgical models that eventually include hospital-based models (eg, joint replacement and soft tissue surgery). Every surgical procedure has unique clinical characteristics that must be considered to optimize study design and conduct. Much of the methodological knowledge garnered from bunion and dental studies is applicable to other surgical models, but some extrapolations are hazardous. The purposes of this review were (1) to qualitatively describe the clinical and experimental characteristics of the 4 classic surgical models: dental extraction, bunionectomy, joint replacement, and soft tissue surgery; and (2) to quantitatively compare the models by analyzing 3 factors: effect size, enrollment rate, and demographics. We found that the dental extraction and bunionectomy models had higher assay sensitivity than the joint replacement and soft tissue surgery models. It is probable that this finding is secondary to the superior experimental conditions under which the dental and bunion models are executed (utilization of few centers that have the ability to reduce surgical, anesthetic, and postoperative confounders).

  1. Low-level laser therapy, at 830 nm, for pain reduction in experimental model of rats with sciatica.

    PubMed

    Bertolini, Gladson Ricardo Flor; Artifon, Elisangela Lourdes; Silva, Taciane Stein da; Cunha, Daniela Martins; Vigo, Priscila Regina

    2011-01-01

    Chronic pain, resulting from nerve compression, is a common clinical presentation. One means of conservative treatment is low-level laser therapy, although controversial. The aim of this study was to evaluate the effects of two doses of low-level laser, at 830 nm, on pain reduction in animals subjected to sciatica. Eighteen rats were used, divided into three groups: GS (n=6), sciatica and simulated treatment; G4J (n=6), sciatica and treatment with 4 J/cm²; and G8J (n=6), sciatica and irradiation with 8 J/cm². The right sciatic nerve was exposed and compressed using catgut thread. Five days of treatment were started on the third postoperative day. Pain was assessed by means of the paw elevation time during gait: before sciatica, before and after the first and second therapies, and the end of the fifth therapy. Low-level laser was effective in reducing the painful condition.

  2. Generating Multimodal References

    ERIC Educational Resources Information Center

    van der Sluis, Ielka; Krahmer, Emiel

    2007-01-01

    This article presents a new computational model for the generation of multimodal referring expressions (REs), based on observations in human communication. The algorithm is an extension of the graph-based algorithm proposed by Krahmer, van Erk, and Verleg (2003) and makes use of a so-called Flashlight Model for pointing. The Flashlight Model…

  3. Multimodal Information Exploration.

    ERIC Educational Resources Information Center

    Stock, Oliviero; Zancanaro, Massimo; Strapparava, Carlo

    1997-01-01

    Discussion of information exploration and software design in computer-based educational systems focuses on the integration of hypermedia and natural language dialog. AlFRESCO is described, an interactive natural language-centered multimodal system that was developed for users interested in frescoes and paintings. (LRW)

  4. Multimode optical fiber

    DOEpatents

    Bigot-Astruc, Marianne; Molin, Denis; Sillard, Pierre

    2014-11-04

    A depressed graded-index multimode optical fiber includes a central core, an inner depressed cladding, a depressed trench, an outer depressed cladding, and an outer cladding. The central core has an alpha-index profile. The depressed claddings limit the impact of leaky modes on optical-fiber performance characteristics (e.g., bandwidth, core size, and/or numerical aperture).

  5. Multimode fiber laser beam cleanup based on stochastic parallel gradient descent algorithm

    NASA Astrophysics Data System (ADS)

    Zhao, Hai-Chuan; Ma, Hao-Tong; Zhou, Pu; Wang, Xiao-Lin; Ma, Yan-Xing; Li, Xiao; Xu, Xiao-Jun; Zhao, Yi-Jun

    2011-01-01

    We present experimental research on multimode fiber laser beam cleanup based on a stochastic parallel gradient descent (SPGD) algorithm. The multimode laser is obtained by injecting a 1064 nm central wavelength single mode fiber laser into a multimode fiber and the system is setup by using phase only liquid crystal spatial light modulators (LC-SLM). The quality evaluation function is increased by a factor of 10.5 and 65% of the laser energy is encircled in the central lobe when the system evolves from open-loop into close-loop state. Experimental results indicate the feasibility of the multimode fiber laser beam cleanup by adaptive optics (AO).

  6. Groin pain

    MedlinePlus

    Pain - groin; Lower abdominal pain; Genital pain; Perineal pain ... Common causes of groin pain include: Pulled muscle, tendon, or ligaments in the leg: This problem often occurs in people who play sports such as ...

  7. Power-compensated displacement sensing based on single mode-multimode fiber Bragg grating structure

    NASA Astrophysics Data System (ADS)

    Sun, An; Wu, Zhishen; Huang, Huang

    2013-01-01

    In this paper, power-compensated displacement sensing is proposed and investigated experimentally based on single mode-multimode fiber Bragg grating (FBG) structure, which is fabricated by a single mode fiber and an FBG written on 105/125 μm graded-index multimode fiber (MMF). Experimental results verify that the reflected peak power of multiple wavelengths in single mode-multimode fiber Bragg grating structure shows different response to displacement induced bending of transmitting multimode fiber as the result of multimode interference (MMI). By employing different bending responses between multiple wavelengths of multimode FBG, ratiometric detection based high sensitive displacement measurement can be achieved, which provides a simple and practical method for displacement sensing and meanwhile a potential solution for multi-parameter measurement.

  8. Nonpharmaceutical approaches to pain management.

    PubMed

    Corti, Lisa

    2014-03-01

    A nonpharmaceutical approach to managing pain is one that does not employ a medication. The use of such approaches, in conjunction with pharmaceuticals as part of multimodal methods to managing pain, is becoming more popular as evidence is emerging to support their use. Cold therapy, for one, is used to reduce the inflammation and tissue damage seen in acute injuries and can be very effective at reducing acute pain. Incorporating the use of superficial heat therapy when treating pain associated with chronic musculoskeletal conditions is often employed as heat increases blood flow, oxygen delivery, and tissue extensibility. Acupuncture is gaining acceptance in veterinary medicine. Research is confirming that release of endogenous endorphins and enkephalins from the application of needles at specific points around the body can effectively control acute and chronic pain. The use of 2 newer therapies-extracorporeal shockwave therapy and platelet-rich plasma-represent an attempt to eliminate the causes of pain at the tissue level by promoting tissue healing and regeneration. Reviewed in this article, these therapies are intended to be used in conjunction with pharmaceuticals as part of a multimodal approach to pain management.

  9. Nonpharmaceutical approaches to pain management.

    PubMed

    Corti, Lisa

    2014-03-01

    A nonpharmaceutical approach to managing pain is one that does not employ a medication. The use of such approaches, in conjunction with pharmaceuticals as part of multimodal methods to managing pain, is becoming more popular as evidence is emerging to support their use. Cold therapy, for one, is used to reduce the inflammation and tissue damage seen in acute injuries and can be very effective at reducing acute pain. Incorporating the use of superficial heat therapy when treating pain associated with chronic musculoskeletal conditions is often employed as heat increases blood flow, oxygen delivery, and tissue extensibility. Acupuncture is gaining acceptance in veterinary medicine. Research is confirming that release of endogenous endorphins and enkephalins from the application of needles at specific points around the body can effectively control acute and chronic pain. The use of 2 newer therapies-extracorporeal shockwave therapy and platelet-rich plasma-represent an attempt to eliminate the causes of pain at the tissue level by promoting tissue healing and regeneration. Reviewed in this article, these therapies are intended to be used in conjunction with pharmaceuticals as part of a multimodal approach to pain management. PMID:25103886

  10. Interventional pain management in the palliative care patient.

    PubMed

    McHugh, Marlene E; Miller-Saultz, Debbie; Wuhrman, Elsa; Kosharskyy, Boleslav

    2012-09-01

    For the majority of patients, cancer pain can be treated using the World Health Organization cancer pain guidelines; however, for 10-20% of patients with advanced cancer, adequate pain control cannot be achieved using these methods owing to disease pathophysiology preventing administration/absorption of pain medications or intolerance due to opioid toxicities. The need to expand analgesic treatment when oral, transdermal, and intravenous therapies fail requires exploration of interventional pain management techniques such as neuraxial (e.g. epidural and intrathecal) infusion therapies and neurolytic interventions. Nurses caring for patients with cancer pain should develop their knowledge of these multimodal approaches to cancer pain management.

  11. Multimodal Nonlinear Optical Microscopy

    PubMed Central

    Yue, Shuhua; Slipchenko, Mikhail N.; Cheng, Ji-Xin

    2013-01-01

    Because each nonlinear optical (NLO) imaging modality is sensitive to specific molecules or structures, multimodal NLO imaging capitalizes the potential of NLO microscopy for studies of complex biological tissues. The coupling of multiphoton fluorescence, second harmonic generation, and coherent anti-Stokes Raman scattering (CARS) has allowed investigation of a broad range of biological questions concerning lipid metabolism, cancer development, cardiovascular disease, and skin biology. Moreover, recent research shows the great potential of using CARS microscope as a platform to develop more advanced NLO modalities such as electronic-resonance-enhanced four-wave mixing, stimulated Raman scattering, and pump-probe microscopy. This article reviews the various approaches developed for realization of multimodal NLO imaging as well as developments of new NLO modalities on a CARS microscope. Applications to various aspects of biological and biomedical research are discussed. PMID:24353747

  12. Evaluation of liposome-encapsulated butorphanol tartrate for alleviation of experimentally induced arthritic pain in green-cheeked conures (Pyrrhura molinae)

    PubMed Central

    Paul-Murphy, Joanne R.; Krugner-Higby, Lisa A.; Tourdot, Renee L.; Sladky, Kurt K.; Klauer, Julia M.; Keuler, Nicholas S.; Brown, Carolyn S.; Heath, Timothy D.

    2014-01-01

    Objective To evaluate injection of microcrystalline sodium urate (MSU) for inducing articular pain in green-cheeked conures (Pyrrhura molinae) and the analgesic efficacy of liposome-encapsulated butorphanol tartrate (LEBT) by use of weight load data, behavioral scores, and fecal corticosterone concentration. Animals 8 conures. Procedures In a crossover study, conures were randomly assigned to receive LEBT (15 mg/kg) or liposomal vehicle subsequent to experimental induction of arthritis or sham injection. The MSU was injected into 1 tibiotarsal-tarsometatarsal (intertarsal) joint to induce arthritis (time 0). Weight-bearing load and behavioral scores were determined at 0, 2, 6, 26, and 30 hours. Results MSU injection into 1 intertarsal joint caused a temporary decrease in weight bearing on the affected limb. Treatment of arthritic conures with LEBT resulted in significantly more weight bearing on the arthritic limb than treatment with vehicle. Administration of vehicle to arthritic conures caused a decrease in activity and feeding behaviors during the induction phase of arthritis, but as the arthritis resolved, there was a significant increase in voluntary activity at 30 hours and feeding behaviors at 26 and 30 hours, compared with results for LEBT treatment of arthritic birds. Treatment with LEBT or vehicle in conures without arthritis resulted in similar measurements for weight bearing and voluntary and motivated behaviors. Conclusions and Clinical Relevance Experimental induction of arthritis in conures was a good method for evaluating tonic pain. Weight-bearing load was the most sensitive measure of pain associated with induced arthritis. Pain associated with MSU-induced arthritis was alleviated by administration of LEBT. PMID:19795935

  13. Breakthrough cancer pain – still a challenge

    PubMed Central

    Margarit, Cesar; Juliá, Joaquim; López, Rafael; Anton, Antonio; Escobar, Yolanda; Casas, Ana; Cruz, Juan Jesús; Galvez, Rafael; Mañas, Ana; Zaragozá, Francisco

    2012-01-01

    Breakthrough cancer pain is defined as transient pain exacerbation in patients with stable and controlled basal pain. Although variable, the prevalence of breakthrough cancer pain is high (33%–95%). According to the American Pain Foundation, breakthrough pain is observed in 50%–90% of all hospitalized cancer patients, in 89% of all patients admitted to homes for the elderly and terminal-patient care centers, and in 35% of all ambulatory care cancer patients. The management of breakthrough cancer pain should involve an interdisciplinary and multimodal approach. The introduction of new fentanyl formulations has represented a great advance and has notably improved treatment. Among these, the pectin-based intranasal formulation adjusts very well to the profile of breakthrough pain attacks, is effective, has a good toxicity profile, and allows for convenient dosing – affording rapid and effective analgesia with the added advantage of being easily administered by caregivers when patients are unable to collaborate. PMID:23204865

  14. Sustained relief of ongoing experimental neuropathic pain by a CRMP2 peptide aptamer with low abuse potential.

    PubMed

    Xie, Jennifer Y; Chew, Lindsey A; Yang, Xiaofang; Wang, Yuying; Qu, Chaoling; Wang, Yue; Federici, Lauren M; Fitz, Stephanie D; Ripsch, Matthew S; Due, Michael R; Moutal, Aubin; Khanna, May; White, Fletcher A; Vanderah, Todd W; Johnson, Philip L; Porreca, Frank; Khanna, Rajesh

    2016-09-01

    Uncoupling the protein-protein interaction between collapsin response mediator protein 2 (CRMP2) and N-type voltage-gated calcium channel (CaV2.2) with an allosteric CRMP2-derived peptide (CBD3) is antinociceptive in rodent models of inflammatory and neuropathic pain. We investigated the efficacy, duration of action, abuse potential, and neurobehavioral toxicity of an improved mutant CRMP2 peptide. A homopolyarginine (R9)-conjugated CBD3-A6K (R9-CBD3-A6K) peptide inhibited the CaV2.2-CRMP2 interaction in a concentration-dependent fashion and diminished surface expression of CaV2.2 and depolarization-evoked Ca influx in rat dorsal root ganglia neurons. In vitro studies demonstrated suppression of excitability of small-to-medium diameter dorsal root ganglion and inhibition of subtypes of voltage-gated Ca channels. Sprague-Dawley rats with tibial nerve injury had profound and long-lasting tactile allodynia and ongoing pain. Immediate administration of R9-CBD3-A6K produced enhanced dopamine release from the nucleus accumbens shell selectively in injured animals, consistent with relief of ongoing pain. R9-CBD3-A6K, when administered repeatedly into the central nervous system ventricles of naive rats, did not result in a positive conditioned place preference demonstrating a lack of abusive liability. Continuous subcutaneous infusion of R9-CBD3-A6K over a 24- to 72-hour period reversed tactile allodynia and ongoing pain, demonstrating a lack of tolerance over this time course. Importantly, continuous infusion of R9-CBD3-A6K did not affect motor activity, anxiety, depression, or memory and learning. Collectively, these results validate the potential therapeutic significance of targeting the CaV-CRMP2 axis for treatment of neuropathic pain. PMID:27537210

  15. Multimode Strong Coupling in Circuit QED

    NASA Astrophysics Data System (ADS)

    Sundaresan, Neereja; Liu, Yanbing; Sadri, Darius; Szocs, Laszlo; Underwood, Devin; Malekakhlagh, Moein; Tureci, Hakan; Houck, Andrew

    We present experimental and theoretical studies in the multimode strong coupling (MMSC) regime of cavity quantum electrodynamics (QED). In MMSC, a single atom is simultaneously coupled to a large, but discrete, number of cavity harmonics, with atom-mode coupling strengths comparable to the free spectral range (FSR). This regime is readily accessible in circuit QED, by strongly coupling a transmon qubit to a low fundamental frequency microwave cavity. We present some key results from our original experiment (PRX 5, 021035, 2015), in which a transmon qubit, resonant with the 75th harmonic of a 90 MHz cavity, reached qubit-mode coupling strengths exceeding 30MHz. When this system is coherently driven, we observed complex multimode fluorescence, with the notable formation of ultra-narrow linewidths. To better understand these unique features of multimode resonance fluorescence we developed a quantum formalism, which attributes the spectral linewidth narrowing to the correlated spontaneous emission of doubly dressed states. Finally we will share preliminary experimental results from our continuing study of MMSC, this time from a system where qubit-mode coupling strengths approach and even exceed the FSR.

  16. A Novel Experimental and Analytical Approach to the Multimodal Neural Decoding of Intent During Social Interaction in Freely-behaving Human Infants

    PubMed Central

    Cruz-Garza, Jesus G.; Hernandez, Zachery R.; Tse, Teresa; Caducoy, Eunice; Abibullaev, Berdakh; Contreras-Vidal, Jose L.

    2015-01-01

    Understanding typical and atypical development remains one of the fundamental questions in developmental human neuroscience. Traditionally, experimental paradigms and analysis tools have been limited to constrained laboratory tasks and contexts due to technical limitations imposed by the available set of measuring and analysis techniques and the age of the subjects. These limitations severely limit the study of developmental neural dynamics and associated neural networks engaged in cognition, perception and action in infants performing “in action and in context”. This protocol presents a novel approach to study infants and young children as they freely organize their own behavior, and its consequences in a complex, partly unpredictable and highly dynamic environment. The proposed methodology integrates synchronized high-density active scalp electroencephalography (EEG), inertial measurement units (IMUs), video recording and behavioral analysis to capture brain activity and movement non-invasively in freely-behaving infants. This setup allows for the study of neural network dynamics in the developing brain, in action and context, as these networks are recruited during goal-oriented, exploration and social interaction tasks. PMID:26485409

  17. Flank pain

    MedlinePlus

    Pain - side; Side pain ... Flank pain can be a sign of a kidney problem. But, since many organs are in this area, other causes are possible. If you have flank pain and fever , chills, blood in the urine, or ...

  18. Abdominal pain

    MedlinePlus

    Stomach pain; Pain - abdomen; Belly ache; Abdominal cramps; Bellyache; Stomachache ... Almost everyone has pain in the abdomen at some point. Most of the time, it is not serious. How bad your pain is ...

  19. Heel pain

    MedlinePlus

    Pain - heel ... Heel pain is most often the result of overuse. However, it may be caused by an injury. Your heel ... on the heel Conditions that may cause heel pain include: Swelling and pain in the Achilles tendon ...

  20. Pain management in veterinary patients with cancer.

    PubMed

    Fan, Timothy M

    2014-09-01

    Pain is a widespread clinical symptom in companion animals with cancer, and its aggressive management should be a priority. Education and skills can be acquired by health care professionals and caregivers to better understand, recognize, and treat cancer-associated pain. The early and rational institution of multimodality analgesic protocols can be highly effective and maximize the chances of improving quality of life in dogs and cats with cancer. This article describes the pathophysiology of pain in companion animals diagnosed with cancer. The foundational causes of cancer-associated pain and treatment strategies for alleviating discomfort in companion animals with cancer are discussed.

  1. A Novel Magnetic Stimulator Increases Experimental Pain Tolerance in Healthy Volunteers - A Double-Blind Sham-Controlled Crossover Study

    PubMed Central

    Kortekaas, Rudie; Konopka, Karl-Heinz; Harbers, Marten; van der Hoeven, Johannes H.; van Wijhe, Marten; Aleman, André; Maurits, Natasha M.

    2013-01-01

    The ‘complex neural pulse’TM (CNP) is a neuromodulation protocol employing weak pulsed electromagnetic fields (PEMF). A pioneering paper reported an analgesic effect in healthy humans after 30 minutes of CNP-stimulation using three nested whole head coils. We aimed to devise and validate a stimulator with a novel design entailing a multitude of small coils at known anatomical positions on a head cap, to improve applicability. The main hypothesis was that CNP delivery with this novel device would also increase heat pain thresholds. Twenty healthy volunteers were enrolled in this double-blind, sham-controlled, crossover study. Thirty minutes of PEMF (CNP) or sham was applied to the head. After one week the other treatment was given. Before and after each treatment, primary and secondary outcomes were measured. Primary outcome was heat pain threshold (HPT) measured with thermal quantitative sensory testing. Other outcomes were warmth detection threshold, and aspects of cognition, emotion and motor performance. As hypothesized heat pain threshold was significantly increased after the PEMF stimulation. All other outcomes were unaltered by the PEMF but there was a trend level reduction of cognitive performance after PEMF stimulation as measured by the digit-symbol substitution task. Results from this pilot study suggest that our device is able to stimulate the brain and to modulate its function. This is in agreement with previous studies that used similar magnetic field strengths to stimulate the brain. Specifically, pain control may be achieved with PEMF and for this analgesic effect, coil design does not appear to play a dominant role. In addition, the flexible configuration with small coils on a head cap improves clinical applicability. Trial Registration Dutch Cochrane Centre NTR1093 PMID:23620795

  2. Chronic pain management: nonpharmacological therapies for chronic pain.

    PubMed

    Chang, Ku-Lang; Fillingim, Roger; Hurley, Robert W; Schmidt, Siegfried

    2015-05-01

    Nonpharmacologic therapies have become a vital part of managing chronic pain (CP). Although these can be used as stand-alone therapies, nonpharmacologic treatments often are used to augment and complement pharmacologic treatments (ie, multimodal therapy). Nonpharmacologic approaches can be classified as behavioral, cognitive, integrative, and physical therapies. Core principles in developing a treatment plan are explaining the nature of the CP condition, setting appropriate goals, and developing a comprehensive treatment approach and plan for adherence. Clinicians should become familiar with these interventions so that they can offer patients flexibility in the pain management approach. Effective noninvasive treatment modalities for CP include behavioral therapy for short-term pain relief; cognitive behavioral therapy for reducing long-term pain and disability; hypnosis as adjunctive therapy; guided imagery, diaphragmatic breathing, and muscle relaxation, especially for cancer-related pain; mindfulness-based stress reduction for patients with chronic low back pain; acupuncture for multiple pain conditions; combination manipulation, manual therapy, endurance exercise, stretching, and strengthening for chronic neck pain; animal-assisted therapy; and S-adenosyl-L-methionine for joint pain. Guidelines for use of these treatment modalities are based on expert panel recommendations in combination with data from randomized controlled trials. PMID:25970869

  3. Challenges of pain control and the role of the ambulatory pain specialist in the outpatient surgery setting.

    PubMed

    Vadivelu, Nalini; Kai, Alice M; Kodumudi, Vijay; Berger, Jack M

    2016-01-01

    Ambulatory surgery is on the rise, with an unmet need for optimum pain control in ambulatory surgery centers worldwide. It is important that there is a proportionate increase in the availability of acute pain-management services to match the rapid rise of clinical patient load with pain issues in the ambulatory surgery setting. Focus on ambulatory pain control with its special challenges is vital to achieve optimum pain control and prevent morbidity and mortality. Management of perioperative pain in the ambulatory surgery setting is becoming increasingly complex, and requires the employment of a multimodal approach and interventions facilitated by ambulatory surgery pain specialists, which is a new concept. A focused ambulatory pain specialist on site at each ambulatory surgery center, in addition to providing safe anesthesia, could intervene early once problematic pain issues are recognized, thus preventing emergency room visits, as well as readmissions for uncontrolled pain. This paper reviews methods of acute-pain management in the ambulatory setting with risk stratification, the utilization of multimodal interventions, including pharmacological and nonpharmacological options, opioids, nonopioids, and various routes with the goal of preventing delayed discharge and unexpected hospital admissions after ambulatory surgery. Continued research and investigation in the area of pain management with outcome studies in acute surgically inflicted pain in patients with underlying chronic pain treated with opioids and the pattern and predictive factors for pain in the ambulatory surgical setting is needed. PMID:27382329

  4. Challenges of pain control and the role of the ambulatory pain specialist in the outpatient surgery setting

    PubMed Central

    Vadivelu, Nalini; Kai, Alice M; Kodumudi, Vijay; Berger, Jack M

    2016-01-01

    Ambulatory surgery is on the rise, with an unmet need for optimum pain control in ambulatory surgery centers worldwide. It is important that there is a proportionate increase in the availability of acute pain-management services to match the rapid rise of clinical patient load with pain issues in the ambulatory surgery setting. Focus on ambulatory pain control with its special challenges is vital to achieve optimum pain control and prevent morbidity and mortality. Management of perioperative pain in the ambulatory surgery setting is becoming increasingly complex, and requires the employment of a multimodal approach and interventions facilitated by ambulatory surgery pain specialists, which is a new concept. A focused ambulatory pain specialist on site at each ambulatory surgery center, in addition to providing safe anesthesia, could intervene early once problematic pain issues are recognized, thus preventing emergency room visits, as well as readmissions for uncontrolled pain. This paper reviews methods of acute-pain management in the ambulatory setting with risk stratification, the utilization of multimodal interventions, including pharmacological and nonpharmacological options, opioids, nonopioids, and various routes with the goal of preventing delayed discharge and unexpected hospital admissions after ambulatory surgery. Continued research and investigation in the area of pain management with outcome studies in acute surgically inflicted pain in patients with underlying chronic pain treated with opioids and the pattern and predictive factors for pain in the ambulatory surgical setting is needed. PMID:27382329

  5. Challenges of pain control and the role of the ambulatory pain specialist in the outpatient surgery setting.

    PubMed

    Vadivelu, Nalini; Kai, Alice M; Kodumudi, Vijay; Berger, Jack M

    2016-01-01

    Ambulatory surgery is on the rise, with an unmet need for optimum pain control in ambulatory surgery centers worldwide. It is important that there is a proportionate increase in the availability of acute pain-management services to match the rapid rise of clinical patient load with pain issues in the ambulatory surgery setting. Focus on ambulatory pain control with its special challenges is vital to achieve optimum pain control and prevent morbidity and mortality. Management of perioperative pain in the ambulatory surgery setting is becoming increasingly complex, and requires the employment of a multimodal approach and interventions facilitated by ambulatory surgery pain specialists, which is a new concept. A focused ambulatory pain specialist on site at each ambulatory surgery center, in addition to providing safe anesthesia, could intervene early once problematic pain issues are recognized, thus preventing emergency room visits, as well as readmissions for uncontrolled pain. This paper reviews methods of acute-pain management in the ambulatory setting with risk stratification, the utilization of multimodal interventions, including pharmacological and nonpharmacological options, opioids, nonopioids, and various routes with the goal of preventing delayed discharge and unexpected hospital admissions after ambulatory surgery. Continued research and investigation in the area of pain management with outcome studies in acute surgically inflicted pain in patients with underlying chronic pain treated with opioids and the pattern and predictive factors for pain in the ambulatory surgical setting is needed.

  6. Pain and motor processing in the human cerebellum.

    PubMed

    Coombes, Stephen A; Misra, Gaurav

    2016-01-01

    Pain-related adaptations in movement require a network architecture that allows for integration across pain and motor circuits. Previous studies addressing this issue have focused on cortical areas such as the midcingulate cortex. Here, we focus on pain and motor processing in the human cerebellum. The goal of this study was to identify areas of activation in the cerebellum, which are common to pain and motor processing, and to determine whether the activation is limited to the superior and inferior cerebellar motor maps or extends into multimodal areas of the posterior cerebellum. Our observations identified overlapping activity in left and right lobules VI and VIIb during pain and motor processing. Activation in these multimodal regions persisted when pain and motor processes were combined within the same trial, and activation in contralateral left lobule VIIb persisted when stimulation was controlled for. Functional connectivity analyses revealed significant correlations in the BOLD time series between multimodal cerebellar regions and sensorimotor regions in the cerebrum including anterior midcingulate cortex, supplementary motor area, and thalamus. The current findings are the first to show multimodal processing in lobules VI and VIIb for motor control and pain processing and suggest that the posterior cerebellum may be important in understanding pain-related adaptations in motor control.

  7. [Chronic knee pain and specific heat phobia. A case report].

    PubMed

    Pepke, W; Neubauer, E; Schiltenwolf, M

    2013-02-01

    This case report presents the medical history of a patient suffering from chronic knee pain with specific heat phobia who had a long history of sick certificates. Using multimodal pain therapy and biofeedback therapy the acquired anxiety disorder could be solved. Long-term working ability could be achieved. PMID:23321701

  8. Magnetic Field Sensing Based on Magnetic-Fluid-Clad Multimode-Singlemode-Multimode Fiber Structures

    PubMed Central

    Tang, Jiali; Pu, Shengli; Dong, Shaohua; Luo, Longfeng

    2014-01-01

    Magnetic field sensing based on magnetic-fluid-clad multimode-singlemode-multimode fiber structures is proposed and experimentalized. The structures are fabricated out using fiber fusion splicing techniques. The sensing principle is based on the interference between the core mode and cladding modes. Two interference dips are observed in our spectral range. Experimental results indicate that the magnetic field sensing sensitivities of 215 pm/mT and 0.5742 dB/mT are obtained for interference dip around 1595 nm. For interference dip around 1565 nm, the sensitivities are 60.5 pm/mT and 0.4821 dB/mT. The response of temperature is also investigated. The temperature sensitivity for the dip around 1595 nm is obtained to be 9.93 pm/°C. PMID:25317761

  9. [Drug treatment and interventional pain therapy in back pain patients].

    PubMed

    Sprott, Haiko; Klauke, Wolfgang

    2013-09-01

    The treatment of chronic, non-malignant low-back pain is based on the patients' history and the clinical examination. It can be assumed that half of the cases present with a neuropathic pain component which needs to be treated with antidepressive and antiepileptic drugs instead of "pure" analgesics. Opioids should be considered with extreme caution because of their toxicity. Chronic non-malignant back pain is the prototype for interdisciplinary treatment approaches and multi-modal interdisciplinary settings, including pain programmes. However, a personalised strategy has to be preferred in most cases. A quick relief of pain is important in order to improve function as well as to re-integrate the patient into professional life. Spinal infiltrations can be of both diagnostic as well as therapeutic benefits. Their indication must be considered carefully, especially if the invasive diagnostic intervention has no therapeutic consequences. The interventional procedures should only be used as part of a multimodal approach in patients without any psychological problem. The sole use of interventions supports the purely somatic orientation of many patients and thus leads us in the wrong direction.

  10. Chronic Low Back Pain: A Personal Approach

    PubMed Central

    Lefort, Paul E.

    1989-01-01

    Sooner or later, all family physicians will face patients with chronic low back pain. This disorder does not result from the same causes and does not respond to the same treatment as acute back pain. A thorough assessment is the key to efficient treatment and should include data about familial, social, and occupational environments. The treatment should be multimodal and tailored to the patient's type of personality and to the causes of the syndrome. PMID:21249069

  11. Medical Image Retrieval: A Multimodal Approach

    PubMed Central

    Cao, Yu; Steffey, Shawn; He, Jianbiao; Xiao, Degui; Tao, Cui; Chen, Ping; Müller, Henning

    2014-01-01

    Medical imaging is becoming a vital component of war on cancer. Tremendous amounts of medical image data are captured and recorded in a digital format during cancer care and cancer research. Facing such an unprecedented volume of image data with heterogeneous image modalities, it is necessary to develop effective and efficient content-based medical image retrieval systems for cancer clinical practice and research. While substantial progress has been made in different areas of content-based image retrieval (CBIR) research, direct applications of existing CBIR techniques to the medical images produced unsatisfactory results, because of the unique characteristics of medical images. In this paper, we develop a new multimodal medical image retrieval approach based on the recent advances in the statistical graphic model and deep learning. Specifically, we first investigate a new extended probabilistic Latent Semantic Analysis model to integrate the visual and textual information from medical images to bridge the semantic gap. We then develop a new deep Boltzmann machine-based multimodal learning model to learn the joint density model from multimodal information in order to derive the missing modality. Experimental results with large volume of real-world medical images have shown that our new approach is a promising solution for the next-generation medical imaging indexing and retrieval system. PMID:26309389

  12. Multimodal imaging of cutaneous wound tissue

    PubMed Central

    Zhang, Shiwu; Gnyawali, Surya; Huang, Jiwei; Ren, Wenqi; Gordillo, Gayle; Sen, Chandan K.; Xu, Ronald

    2015-01-01

    Abstract. Quantitative assessment of wound tissue ischemia, perfusion, and inflammation provides critical information for appropriate detection, staging, and treatment of chronic wounds. However, few methods are available for simultaneous assessment of these tissue parameters in a noninvasive and quantitative fashion. We integrated hyperspectral, laser speckle, and thermographic imaging modalities in a single-experimental setup for multimodal assessment of tissue oxygenation, perfusion, and inflammation characteristics. Algorithms were developed for appropriate coregistration between wound images acquired by different imaging modalities at different times. The multimodal wound imaging system was validated in an occlusion experiment, where oxygenation and perfusion maps of a healthy subject’s upper extremity were continuously monitored during a postocclusive reactive hyperemia procedure and compared with standard measurements. The system was also tested in a clinical trial where a wound of three millimeters in diameter was introduced on a healthy subject’s lower extremity and the healing process was continuously monitored. Our in vivo experiments demonstrated the clinical feasibility of multimodal cutaneous wound imaging. PMID:25604545

  13. Medical Image Retrieval: A Multimodal Approach.

    PubMed

    Cao, Yu; Steffey, Shawn; He, Jianbiao; Xiao, Degui; Tao, Cui; Chen, Ping; Müller, Henning

    2014-01-01

    Medical imaging is becoming a vital component of war on cancer. Tremendous amounts of medical image data are captured and recorded in a digital format during cancer care and cancer research. Facing such an unprecedented volume of image data with heterogeneous image modalities, it is necessary to develop effective and efficient content-based medical image retrieval systems for cancer clinical practice and research. While substantial progress has been made in different areas of content-based image retrieval (CBIR) research, direct applications of existing CBIR techniques to the medical images produced unsatisfactory results, because of the unique characteristics of medical images. In this paper, we develop a new multimodal medical image retrieval approach based on the recent advances in the statistical graphic model and deep learning. Specifically, we first investigate a new extended probabilistic Latent Semantic Analysis model to integrate the visual and textual information from medical images to bridge the semantic gap. We then develop a new deep Boltzmann machine-based multimodal learning model to learn the joint density model from multimodal information in order to derive the missing modality. Experimental results with large volume of real-world medical images have shown that our new approach is a promising solution for the next-generation medical imaging indexing and retrieval system.

  14. Multimode model for projective photon-counting measurements

    SciTech Connect

    Tualle-Brouri, Rosa; Ourjoumtsev, Alexei; Dantan, Aurelien; Grangier, Philippe; Wubs, Martijn; Soerensen, Anders S.

    2009-07-15

    We present a general model to account for the multimode nature of the quantum electromagnetic field in projective photon-counting measurements. We focus on photon-subtraction experiments, where non-Gaussian states are produced conditionally. These are useful states for continuous-variable quantum-information processing. We present a general method called mode reduction that reduces the multimode model to an effective two-mode problem. We apply this method to a multimode model describing broadband parametric down-conversion, thereby improving the analysis of existing experimental results. The main improvement is that spatial and frequency filters before the photon detector are taken into account explicitly. We find excellent agreement with previously published experimental results, using fewer free parameters than before, and discuss the implications of our analysis for the optimized production of states with negative Wigner functions.

  15. Chronic pain management as a barrier to pediatric palliative care.

    PubMed

    Thompson, Lindsay A; Meinert, Elizabeth; Baker, Kimberly; Knapp, Caprice

    2013-12-01

    Pain is common as a presenting complaint to outpatient and emergency departments for children, yet pain management represents one of the children's largest unmet needs. A child may present with acute pain for an intermittent issue or may have acute or chronic pain in the setting of chronic illness. The mainstay of treatment for pain uses a stepwise approach for pain management, such as set up by the World Health Organization. For children with life-limiting illnesses, the Institute of Medicine guidelines recommends referral upon diagnosis for palliative care, meaning that the child receives comprehensive services that include pain control in coordination with curative therapies; yet barriers remain. From the provider perspective, pain can be better addressed through a careful assessment of one's own knowledge, skills, and attitudes. The key components of pain management in children are multimodal, regardless of the cause of the pain. PMID:23329083

  16. Chronic pain management as a barrier to pediatric palliative care.

    PubMed

    Thompson, Lindsay A; Meinert, Elizabeth; Baker, Kimberly; Knapp, Caprice

    2013-12-01

    Pain is common as a presenting complaint to outpatient and emergency departments for children, yet pain management represents one of the children's largest unmet needs. A child may present with acute pain for an intermittent issue or may have acute or chronic pain in the setting of chronic illness. The mainstay of treatment for pain uses a stepwise approach for pain management, such as set up by the World Health Organization. For children with life-limiting illnesses, the Institute of Medicine guidelines recommends referral upon diagnosis for palliative care, meaning that the child receives comprehensive services that include pain control in coordination with curative therapies; yet barriers remain. From the provider perspective, pain can be better addressed through a careful assessment of one's own knowledge, skills, and attitudes. The key components of pain management in children are multimodal, regardless of the cause of the pain.

  17. Comprehensive management of chronic pain in haemophilia.

    PubMed

    Young, G; Tachdjian, R; Baumann, K; Panopoulos, G

    2014-03-01

    Chronic pain, most often due to haemophilic arthropathy, is a pervasive problem in persons with haemophilia (PWH) that adversely impacts function and quality of life. PWH with inhibitors and older PWH may be especially vulnerable to progressive arthropathy and resulting chronic pain. The development of chronic pain from acute pain involves a complex interplay of biological and psychosocial factors that may all contribute to the perpetuation of chronic pain and the outcome of therapy. In the absence of evidence-based guidelines, an individualized, multimodal approach to chronic pain management is proposed, as it is in individuals without haemophilia who have chronic pain. Pharmacological treatment is central to the management of chronic pain and must be modified based on pain intensity, ongoing response to therapy and the risk for adverse events. Non-pharmacological interventions, including physiotherapy, complementary treatments and surgical (e.g. orthopaedic) or other invasive procedures, may be integral to chronic pain management in this population. Ongoing psychosocial assessment is critical to identify those factors that may be contributing to the perpetuation of chronic pain or acting as barriers to effective management. Additional study is needed to identify optimal pharmacological treatments for chronic pain in PWH based on the unique pathophysiology of haemophilic arthropathy and on risk profile. Systematic determination of the particular psychosocial factors impacting the experience and management of chronic pain in PWH would likewise add value to the treatment of this pervasive problem.

  18. Back Pain

    MedlinePlus

    ... Back Pain Find a Clinical Trial Journal Articles Back Pain March 2015 Handout on Health: Back Pain This publication is for people who have back ... to discuss them with your doctor. What Is Back Pain? Back pain is an all-too-familiar problem ...

  19. Chest pain

    MedlinePlus

    ... provider may ask questions such as: Is the pain between the shoulder blades? Under the breast bone? Does the pain ... How long does the pain last? Does the pain go from your chest into your shoulder, arm, neck, jaw, or back? Is the pain ...

  20. Postural Responses to a Suddenly Released Pulling Force in Older Adults with Chronic Low Back Pain: An Experimental Study

    PubMed Central

    Lee, Pei-Yun; Lin, Sang-I; Liao, Yu-Ting; Lin, Ruey-Mo; Hsu, Che-Chia; Huang, Kuo-Yuan; Chen, Yi-Ting

    2016-01-01

    Chronic low back pain (CLBP), one of the most common musculoskeletal conditions in older adults, might affect balance and functional independence. The purpose of this study was to investigate the postural responses to a suddenly released pulling force in older adults with and without CLBP. Thirty community-dwelling older adults with CLBP and 26 voluntary controls without CLBP were enrolled. Participants were required to stand on a force platform while, with one hand, they pulled a string that was fastened at the other end to a 2-kg or to a 4-kg force in the opposite direction at a random order. The number of times the participants lost their balance and motions of center of pressure (COP) when the string was suddenly released were recorded. The results demonstrated that although the loss of balance rates for each pulling force condition did not differ between groups, older adults with CLBP had poorer postural responses: delayed reaction, larger displacement, higher velocity, longer path length, and greater COP sway area compared to the older controls. Furthermore, both groups showed larger postural responses in the 4-kg pulling force condition. Although aging is generally believed to be associated with declining balance and postural control, these findings highlight the effect of CLBP on reactive balance when responding to an externally generated force in an older population. This study also suggests that, for older adults with CLBP, in addition to treating them for pain and disability, reactive balance evaluation and training, such as reaction and movement strategy training should be included in their interventions. Clinicians and older patients with CLBP need to be made aware of the significance of impaired reactive balance and the increased risk of falls when encountering unexpected perturbations. PMID:27622646

  1. Postural Responses to a Suddenly Released Pulling Force in Older Adults with Chronic Low Back Pain: An Experimental Study.

    PubMed

    Lee, Pei-Yun; Lin, Sang-I; Liao, Yu-Ting; Lin, Ruey-Mo; Hsu, Che-Chia; Huang, Kuo-Yuan; Chen, Yi-Ting; Tsai, Yi-Ju

    2016-01-01

    Chronic low back pain (CLBP), one of the most common musculoskeletal conditions in older adults, might affect balance and functional independence. The purpose of this study was to investigate the postural responses to a suddenly released pulling force in older adults with and without CLBP. Thirty community-dwelling older adults with CLBP and 26 voluntary controls without CLBP were enrolled. Participants were required to stand on a force platform while, with one hand, they pulled a string that was fastened at the other end to a 2-kg or to a 4-kg force in the opposite direction at a random order. The number of times the participants lost their balance and motions of center of pressure (COP) when the string was suddenly released were recorded. The results demonstrated that although the loss of balance rates for each pulling force condition did not differ between groups, older adults with CLBP had poorer postural responses: delayed reaction, larger displacement, higher velocity, longer path length, and greater COP sway area compared to the older controls. Furthermore, both groups showed larger postural responses in the 4-kg pulling force condition. Although aging is generally believed to be associated with declining balance and postural control, these findings highlight the effect of CLBP on reactive balance when responding to an externally generated force in an older population. This study also suggests that, for older adults with CLBP, in addition to treating them for pain and disability, reactive balance evaluation and training, such as reaction and movement strategy training should be included in their interventions. Clinicians and older patients with CLBP need to be made aware of the significance of impaired reactive balance and the increased risk of falls when encountering unexpected perturbations. PMID:27622646

  2. Multimode corrugated waveguide feed for monopulse radar

    NASA Astrophysics Data System (ADS)

    Clarricoats, P. J. B.; Elliot, R. D.

    1981-04-01

    The paper describes the behavior of a multimode corrugated feed for use in monopulse radar. Four square input waveguides are used to excite sum- and difference-channel modes. With appropriate choice of parameters it is possible to generate radiation patterns with low crosspolarization thus allowing the polarization characteristics of a target to be obtained. The results of an analysis of the relevant waveguide discontinuity problem are presented and a means to compensate phase differences between modes is also described. Some preliminary experimental results are found to be in accord with theory.

  3. [Organized pain management in the DRG reimbursement system].

    PubMed

    Lindena, G; Gerbershagen, H U; Zenz, M; Laubenthal, H; Schleppers, A

    2005-02-01

    Multidisciplinary pain management in pain centers can only be guaranteed if the DRG reimbursement system takes into account the multiple risk factors. The German pain associations prospectively analyzed clinical and administrative (DRG-related) data sets (n=3943) of inpatient and day care pain treatment facilities. The index diagnoses of 84% of the patient sample were grouped into nine basic DRGs. The most frequent pain procedure code was 8-918 ("multimodal pain management"). The minimal length of stay for this code set to 7 days was 17.2 days for the study sample. The DRG grouper software 2003 categorized 68.6% of the patients into PCCL 0 despite the proven complexity of risks and secondary diseases. The mean case weight in the sample was set at about 1. The pain-related data set analyzing pain severity, chronicity, and its influence on various functions emphasizes the total severity and burden of disease and thus the necessity for multimodal pain management. The German pain societies carried the motion that a new complex ICD code for chronic pain (with biopsychosocial consequences) should be established in the German Modification of the ICD. The new ICD code F62.80 and the procedure code 8-918 had not yet been implemented into the German DRG algorithm. Due to modifications in DRG systematics and the DRG algorithm, to be activated in 2005, the procedure code 8-918 will now automatically trigger into four special basic pain DRGs corresponding to the index pain diagnosis.

  4. Expression of CXCR3 on specific T cells is essential for homing to the prostate gland in an experimental model of chronic prostatitis/chronic pelvic pain syndrome.

    PubMed

    Breser, Maria L; Motrich, Ruben D; Sanchez, Leonardo R; Mackern-Oberti, Juan P; Rivero, Virginia E

    2013-04-01

    Experimental autoimmune prostatitis (EAP) is considered a valid model for the human disease chronic prostatitis/chronic pelvic pain syndrome. In this report, we analyzed phenotypic characteristics of T cells that gain access to the prostate and induce leukocyte recruitment in mice with different susceptibility to EAP. After EAP induction, NOD mice developed a specific cellular response characterized by a mixed Th1/Th17 pattern with specific T cells mainly expressing CXCR3 that infiltrated and damaged the prostate. In contrast, BALB/c mice, as well as NOD-IFN-γ(-/-), exhibited only Th17 cells mainly expressing CCR6 that were not capable of infiltrating the prostate gland. Adoptive transfer experiments of T cells from NOD or NOD-IFN-γ(-/-) mice to NOD-SCID recipients showed that only T cells from NOD mice successfully infiltrated the prostate. However, after "in vitro" or "in vivo" treatment with rIFN-γ, T cells from NOD-IFN-γ(-/-) mice became capable of homing to the prostate and induced leukocyte recruitment. Chemokine levels in prostate tissue from NOD mice showed increased expression levels of CXCR3 ligands. Additional experiments using adoptive transfer of sorted CXCR3(+)CD3(+) T cells or administrating a CXCR3 antagonist treatment confirmed these previous results. Altogether, our results demonstrate that the expression of CXCR3 on effector T cells is essential for their homing to the prostate gland in EAP. CXCR3 emerges as a potential therapeutic target to control chronic prostatitis/chronic pelvic pain syndrome.

  5. Pain Relievers

    MedlinePlus

    Pain relievers are medicines that reduce or relieve headaches, sore muscles, arthritis, or other aches and pains. There ... also have a slightly different response to a pain reliever. Over-the-counter (OTC) medicines are good for ...

  6. Elbow pain

    MedlinePlus

    Pain - elbow ... Elbow pain can be caused by many problems. A common cause in adults is tendinitis . This is inflammation and ... a partial dislocation ). Other common causes of elbow pain are: Bursitis -- inflammation of a fluid-filled cushion ...

  7. Eye pain

    MedlinePlus

    Ophthalmalgia; Pain - eye ... Pain in the eye can be an important symptom of a health problem. Make sure you tell your health care provider if you have eye pain that does not go away. Tired eyes or ...

  8. Ankle pain

    MedlinePlus

    Pain - ankle ... Ankle pain is often due to an ankle sprain. An ankle sprain is an injury to the ligaments, which ... the joint. In addition to ankle sprains, ankle pain can be caused by: Damage or swelling of ...

  9. Foot pain

    MedlinePlus

    Pain - foot ... Foot pain may be due to: Aging Being on your feet for long periods of time Being overweight A ... sports activity Trauma The following can cause foot pain: Arthritis and gout . Common in the big toe, ...

  10. Wrist pain

    MedlinePlus

    Pain - wrist; Pain - carpal tunnel; Injury - wrist; Arthritis - wrist; Gout - wrist; Pseudogout - wrist ... Carpal tunnel syndrome: A common cause of wrist pain is carpal tunnel syndrome . You may feel aching, ...

  11. Knee pain

    MedlinePlus

    Pain - knee ... Knee pain can have different causes. Being overweight puts you at greater risk for knee problems. Overusing your knee can trigger knee problems that cause pain. If you have a history of arthritis, it ...

  12. Back Pain

    MedlinePlus

    ... BACK PAIN? There are many possible causes of low back pain, including stretched (strained) muscles, torn or stretched (sprained) ... appear to be at an increased risk for low back pain in comparison to the general population (estimates range ...

  13. Leg pain

    MedlinePlus

    Pain - leg; Aches - leg; Cramps - leg ... Leg pain can be due to a muscle cramp (also called a charley horse ). Common causes of ... a long time An injury can also cause leg pain from: A torn or overstretched muscle ( strain ) ...

  14. Depression, Pain, and Pain Behavior.

    ERIC Educational Resources Information Center

    Keefe, Francis J.; And Others

    1986-01-01

    Examined the degree to which depression predicted pain and pain behavior. The Beck Depression Inventory was administered to 207 low back pain patients. Depression and physical findings were the most important predictors of pain and pain behavior. Depression proved significant even after controlling for important demographic and medical status…

  15. Design, Performance and Optimization for Multimodal Radar Operation

    PubMed Central

    Bhat, Surendra S.; Narayanan, Ram M.; Rangaswamy, Muralidhar

    2012-01-01

    This paper describes the underlying methodology behind an adaptive multimodal radar sensor that is capable of progressively optimizing its range resolution depending upon the target scattering features. It consists of a test-bed that enables the generation of linear frequency modulated waveforms of various bandwidths. This paper discusses a theoretical approach to optimizing the bandwidth used by the multimodal radar. It also discusses the various experimental results obtained from measurement. The resolution predicted from theory agrees quite well with that obtained from experiments for different target arrangements.

  16. Long-Term Effects of Interprofessional Biopsychosocial Rehabilitation for Adults with Chronic Non-Specific Low Back Pain: A Multicentre, Quasi-Experimental Study

    PubMed Central

    Semrau, Jana; Hentschke, Christian; Buchmann, Jana; Meng, Karin; Vogel, Heiner; Faller, Hermann; Bork, Hartmut; Pfeifer, Klaus

    2015-01-01

    Background Improvement of the long-term effectiveness of multidisciplinary ortho-paedic rehabilitation (MOR) in the management of chronic non-specific low back pain (CLBP) remains a central issue for health care in Germany. We developed an interprofessional and interdisciplinary, biopsychosocial rehabilitation concept named “PASTOR” to promote self-management in adults with CLBP and compared its effectiveness with the current model of MOR. Methods A multicentre quasi-experimental study with three measurement time points was implemented. 680 adults aged 18 to 65 with CLBP were assed for eligibil-ity in three inpatient rehabilitation centres in Germany. At first the effects of the MOR, with a total extent of 48 hours (control group), were assessed. Thereafter, PASTOR was implemented and evaluated in the same centres (intervention group). It consisted of six interprofessional modules, which were provided on 12 days in fixed groups, with a total extent of 48 hours. Participants were assessed with self-report measures at baseline, discharge, and 12 months for functional ability (primary outcome) using the Hannover Functional Ability Questionnaire (FFbH-R) and vari-ous secondary outcomes (e.g. pain, health status, physical activity, pain coping, pain-related cognitions). Results In total 536 participants were consecutively assigned to PASTOR (n=266) or MOR (n=270). At 12 months, complete data of 368 participants was available. The adjusted between-group difference in the FFbH-R at 12 months was 6.58 (95% CI 3.38 to 9.78) using complete data and 3.56 (95% CI 0.45 to 6.67) using available da-ta, corresponding to significant small-to-medium effect sizes of d=0.42 (p<0.001) and d=0.10 (p=0.025) in favour of PASTOR. Further improvements in secondary out-comes were also observed in favour of PASTOR. Conclusion The interprofessional and interdisciplinary, biopsychosocial rehabilita-tion program PASTOR shows some improvements of the long-term effectiveness of inpatient

  17. Options for perioperative pain management in neurosurgery

    PubMed Central

    Vadivelu, Nalini; Kai, Alice M; Tran, Daniel; Kodumudi, Gopal; Legler, Aron; Ayrian, Eugenia

    2016-01-01

    Moderate-to-severe pain following neurosurgery is common but often does not get attention and is therefore underdiagnosed and undertreated. Compounding this problem is the traditional belief that neurosurgical pain is inconsequential and even dangerous to treat. Concerns about problematic effects associated with opioid analgesics such as nausea, vomiting, oversedation, and increased intracranial pressure secondary to elevated carbon dioxide tension from respiratory depression have often led to suboptimal postoperative analgesic strategies in caring for neurosurgical patients. Neurosurgical patients may have difficulty or be incapable of communicating their need for analgesics due to neurologic deficits, which poses an additional challenge. Postoperative pain control should be a priority, because pain adversely affects recovery and patient outcomes. Inconsistent practices and the quality of current analgesic strategies for neurosurgical patients still leave room for improvement. Given the complexity of postoperative pain management for these patients, multimodal strategies are often required to optimize pain control and at the same time limit undesired side effects. PMID:26929661

  18. Investigational pharmacology for low back pain

    PubMed Central

    Bhandary, Avinash K; Chimes, Gary P; Malanga, Gerard A

    2010-01-01

    Study design: Review and reinterpretation of existing literature. Objective: This review article summarizes the anatomy and pathogenesis of disease processes that contribute to low back pain, and discusses key issues in existing therapies for chronic low back pain. The article also explains the scientific rationale for investigational pharmacology and highlights emerging compounds in late development. Results/conclusion: While the diverse and complex nature of chronic low back pain continues to challenge clinicians, a growing understanding of chronic low back pain on a cellular level has refined our approach to managing chronic low back pain with pharmacology. Many emerging therapies with improved safety profiles are currently in the research pipeline and will contribute to a multimodal therapeutic algorithm in the near future. With the heterogeneity of the patient population suffering from chronic low back pain, the clinical challenge will be accurately stratifying the optimal pharmacologic approach for each patient. PMID:21197321

  19. Patellofemoral pain.

    PubMed

    Crossley, Kay M; Callaghan, Michael J; van Linschoten, Robbart

    2016-02-01

    Patellofemoral pain refers to pain behind or around the patella (also known as patellofemoral pain syndrome, anterior knee pain, runner's knee, and, formerly, chondromalacia patellae). Patellofemoral pain is common, accounting for 11-17% of all knee pain presentations to general practice.(1 2) While it typically occurs in physically active people aged <40 years, it also affects people of all activity levels and ages.(1 2) Patellofemoral pain can be diagnosed in the clinic, and evidence based treatments can reduce pain and improve function, allowing patients to maintain a physically active lifestyle. PMID:26834209

  20. Delivery of ultrashort spatially focused pulses through a multimode fiber

    NASA Astrophysics Data System (ADS)

    Morales-Delgado, Edgar E.; Papadopoulos, Ioannis N.; Farahi, Salma; Psaltis, Demetri; Moser, Christophe

    2015-08-01

    Multimode optical fibers potentially allow the transmission of larger amounts of information than their single mode counterparts because of their high number of supported modes. However, propagation of a light pulse through a multimode fiber suffers from spatial distortions due to the superposition of the various exited modes and from time broadening due to modal dispersion. We present a method based on digital phase conjugation to selectively excite in a multimode fiber specific optical fiber modes that follow similar optical paths as they travel through the fiber. The excited modes interfere constructively at the fiber output generating an ultrashort spatially focused pulse. The excitation of a limited number of modes following similar optical paths limits modal dispersion, allowing the transmission of the ultrashort pulse. We have experimentally demonstrated the delivery of a focused spot of pulse width equal to 500 fs through a 30 cm, 200 micrometer core step index multimode fiber. The results of this study show that two-photon imaging capability can be added to ultra-thin lensless endoscopy using commercial multimode fibers.

  1. Curine, an alkaloid isolated from Chondrodendron platyphyllum inhibits prostaglandin E2 in experimental models of inflammation and pain.

    PubMed

    Leite, Fagner Carvalho; Ribeiro-Filho, Jaime; Costa, Hermann Ferreira; Salgado, Paula Regina Rodrigues; Calheiros, Andrea Surrage; Carneiro, Alan Brito; de Almeida, Reinaldo Nobrega; Dias, Celidarque da Silva; Bozza, Patricia T; Piuvezam, Marcia Regina

    2014-08-01

    Curine is a bisbenzylisoquinoline alkaloid that is isolated from Chondrodendron platyphyllum, a plant that is used to treat malaria, inflammation, and pain. Recent reports have demonstrated the antiallergic effects of curine at nontoxic doses. However, its anti-inflammatory and analgesic properties remain to be elucidated. This study investigated the anti-inflammatory and analgesic effects of curine in mice. We analyzed the effects of an oral treatment with curine in the formation of paw edema, vascular permeability, abdominal contortion, licking behavior, and hyperalgesia using different inflammatory stimuli. Curine significantly inhibited the formation of paw edema by decreasing vascular permeability, inhibited the acetic acid-induced writhing response, inhibited the licking behavior during inflammation but not during the neurogenic phase of the formalin test, and inhibited carrageenan-induced hyperalgesia. Finally, curine inhibited prostaglandin E2 production in vitro without affecting cyclooxygenase-2 expression. The effects of curine treatment were similar to the effects of indomethacin, but were different from the effects of morphine treatment, suggesting that the analgesic effects of curine do not result from the direct inhibition of neuronal activation but instead depend on anti-inflammatory mechanisms that, at least in part, result from the inhibition of prostaglandin E2 production. In conclusion, curine presents anti-inflammatory and analgesic effects at nontoxic doses and has the potential for use in anti-inflammatory drug development.

  2. A review of morphine and morphine-6-glucuronide's pharmacokinetic-pharmacodynamic relationships in experimental and clinical pain.

    PubMed

    Sverrisdóttir, Eva; Lund, Trine Meldgaard; Olesen, Anne Estrup; Drewes, Asbjørn Mohr; Christrup, Lona Louring; Kreilgaard, Mads

    2015-07-10

    Morphine is a widely used opioid for treatment of moderate to severe pain, but large interindividual variability in patient response and no clear guidance on how to optimise morphine dosage regimen complicates treatment strategy for clinicians. Population pharmacokinetic-pharmacodynamic models can be used to quantify dose-response relationships for the population as well as interindividual and interoccasion variability. Additionally, relevant covariates for population subgroups that deviate from the typical population can be identified and help clinicians in dose optimisation. This review provides a detailed overview of the published human population pharmacokinetic-pharmacodynamic studies for morphine analgesia in addition to basic drug disposition and pharmacological properties of morphine and its analgesic active metabolite, morphine-6-glucuronide, that may help identify future covariates. Furthermore, based on simulations from key pharmacokinetic-pharmacodynamic models, the contribution of morphine-6-glucuronide to the analgesic response in patients with renal insufficiency was investigated. Simulations were also used to examine the impact of effect-site equilibration half-life on time course of response. Lastly, the impact of study design on the likelihood of determining accurate pharmacodynamic parameters for morphine response was evaluated.

  3. Curine, an alkaloid isolated from Chondrodendron platyphyllum inhibits prostaglandin E2 in experimental models of inflammation and pain.

    PubMed

    Leite, Fagner Carvalho; Ribeiro-Filho, Jaime; Costa, Hermann Ferreira; Salgado, Paula Regina Rodrigues; Calheiros, Andrea Surrage; Carneiro, Alan Brito; de Almeida, Reinaldo Nobrega; Dias, Celidarque da Silva; Bozza, Patricia T; Piuvezam, Marcia Regina

    2014-08-01

    Curine is a bisbenzylisoquinoline alkaloid that is isolated from Chondrodendron platyphyllum, a plant that is used to treat malaria, inflammation, and pain. Recent reports have demonstrated the antiallergic effects of curine at nontoxic doses. However, its anti-inflammatory and analgesic properties remain to be elucidated. This study investigated the anti-inflammatory and analgesic effects of curine in mice. We analyzed the effects of an oral treatment with curine in the formation of paw edema, vascular permeability, abdominal contortion, licking behavior, and hyperalgesia using different inflammatory stimuli. Curine significantly inhibited the formation of paw edema by decreasing vascular permeability, inhibited the acetic acid-induced writhing response, inhibited the licking behavior during inflammation but not during the neurogenic phase of the formalin test, and inhibited carrageenan-induced hyperalgesia. Finally, curine inhibited prostaglandin E2 production in vitro without affecting cyclooxygenase-2 expression. The effects of curine treatment were similar to the effects of indomethacin, but were different from the effects of morphine treatment, suggesting that the analgesic effects of curine do not result from the direct inhibition of neuronal activation but instead depend on anti-inflammatory mechanisms that, at least in part, result from the inhibition of prostaglandin E2 production. In conclusion, curine presents anti-inflammatory and analgesic effects at nontoxic doses and has the potential for use in anti-inflammatory drug development. PMID:25197953

  4. Positive Traits Linked to Less Pain through Lower Pain Catastrophizing

    PubMed Central

    Hood, Anna; Pulvers, Kim; Carrillo, Janet; Merchant, Gina; Thomas, Marie

    2011-01-01

    The present study examined the association between positive traits, pain catastrophizing, and pain perceptions. We hypothesized that pain catastrophizing would mediate the relationship between positive traits and pain. First, participants (n = 114) completed the Trait Hope Scale, the Life Orientation Test- Revised, and the Pain Catastrophizing Scale. Participants then completed the experimental pain stimulus, a cold pressor task, by submerging their hand in a circulating water bath (0º Celsius) for as long as tolerable. Immediately following the task, participants completed the Short-Form McGill Pain Questionnaire (MPQ-SF). Pearson correlation found associations between hope and pain catastrophizing (r = −.41, p < .01) and MPQ-SF scores (r = −.20, p < .05). Optimism was significantly associated with pain catastrophizing (r = −.44, p < .01) and MPQ-SF scores (r = −.19, p < .05). Bootstrapping, a non-parametric resampling procedure, tested for mediation and supported our hypothesis that pain catastrophizing mediated the relationship between positive traits and MPQ-SF pain report. To our knowledge, this investigation is the first to establish that the protective link between positive traits and experimental pain operates through lower pain catastrophizing. PMID:22199416

  5. Pelvic Pain

    MedlinePlus

    Pelvic pain occurs mostly in the lower abdomen area. The pain might be steady, or it might come and go. If the pain is severe, it might get in the way ... re a woman, you might feel a dull pain during your period. It could also happen during ...

  6. Shoulder pain

    MedlinePlus

    Pain - shoulder ... changes around the rotator cuff can cause shoulder pain. You may have pain when lifting the arm above your head or ... The most common cause of shoulder pain occurs when rotator cuff tendons ... The tendons become inflamed or damaged. This condition ...

  7. Back Pain

    MedlinePlus

    ... Awards Enhancing Diversity Find People About NINDS NINDS Back Pain Information Page Condensed from Low Back Pain Fact ... en Español Additional resources from MedlinePlus What is Back Pain? Acute or short-term low back pain generally ...

  8. [Multimodal iatrogenic apathy].

    PubMed

    Oliveira-Souza, R D; Figueiredo, W M

    1996-06-01

    The present paper reports on five patients who developed apathy as a peculiar side effect of antidepressants. Their behavioral and psychopathological changes were primarily due to the near-absence of emotional experience, a key characteristic that distinguishes apathy from avolition and abulia. The emergence of apathy in the course of an antidepressant treatment should raise the suspicion of an adverse effect of the drug and lead to its prompt withdrawal. A sample of the relevant clinical evidence favoring the distinction of apathy confined to a single sensory domain ("unimodal apathy") from apathy confined to more than one sensory realm ("multimodal apathy") is reviewed. From a pathophysiological standpoint, it would appear that neural nets centered in the amygdala-temporo polar cortex are critical for the integration of sensory perceptions and mental imagery with appropriate emotional tone and quality as well as with their accompanying somatic markers, as they receive afferents from the major projection systems of the prosencephalon and lie in nodes strategic to modify the ongoing activity of multiple parallel brain systems. The fact that one common symptom can be produced by such a heterogeneous family of substances points to a shared neurochemical mechanism of action. At present, discrete cerebral serotoninergic circuits would appear to be suitable candidates for such a role. Cases as these may be critical for the understanding of the cerebral organization of emotions in man, lending support to the notion that distinct neurochemical systems mediate discrete psychopathological symptoms.

  9. Multimodal Communication in Chimpanzees

    PubMed Central

    TAGLIALATELA, JARED P.; RUSSELL, JAMIE L.; POPE, SARAH M.; MORTON, TAMARA; BOGART, STEPHANIE; REAMER, LISA A.; SCHAPIRO, STEVEN J.; HOPKINS, WILLIAM D.

    2016-01-01

    A fundamental characteristic of human language is multimodality. In other words, humans use multiple signaling channels concurrently when communicating with one another. For example, people frequently produce manual gestures while speaking, and the words a person perceives are impacted by visual information. For this study, we hypothesized that similar to the way that humans regularly couple their spoken utterances with gestures and facial expressions, chimpanzees regularly produce vocalizations in conjunction with other communicative signals. To test this hypothesis, data were collected from 101 captive chimpanzees living in mixed-sex social groupings of seven to twelve individuals. A total of 2,869 vocal events were collected. The data indicate that approximately 50% of the vocal events were produced in conjunction with another communicative modality. In addition, approximately 68% were directed to a specific individual, and these directed vocalizations were more likely to include a signal from another communicative modality than were vocalizations that were not directed to a specific individual. These results suggest that, like humans, chimpanzees often pair their vocalizations with signals from other communicative modalities. In addition, chimpanzees appear to use their communicative signals strategically to meet specific socio-communicative ends, providing support for the growing literature that indicates that at least some chimpanzee vocal signaling is intentional. PMID:26212686

  10. Multimode Silicon Nanowire Transistors

    PubMed Central

    2014-01-01

    The combined capabilities of both a nonplanar design and nonconventional carrier injection mechanisms are subject to recent scientific investigations to overcome the limitations of silicon metal oxide semiconductor field effect transistors. In this Letter, we present a multimode field effect transistors device using silicon nanowires that feature an axial n-type/intrinsic doping junction. A heterostructural device design is achieved by employing a self-aligned nickel-silicide source contact. The polymorph operation of the dual-gate device enabling the configuration of one p- and two n-type transistor modes is demonstrated. Not only the type but also the carrier injection mode can be altered by appropriate biasing of the two gate terminals or by inverting the drain bias. With a combined band-to-band and Schottky tunneling mechanism, in p-type mode a subthreshold swing as low as 143 mV/dec and an ON/OFF ratio of up to 104 is found. As the device operates in forward bias, a nonconventional tunneling transistor is realized, enabling an effective suppression of ambipolarity. Depending on the drain bias, two different n-type modes are distinguishable. The carrier injection is dominated by thermionic emission in forward bias with a maximum ON/OFF ratio of up to 107 whereas in reverse bias a Schottky tunneling mechanism dominates the carrier transport. PMID:25303290

  11. Multimode silicon nanowire transistors.

    PubMed

    Glassner, Sebastian; Zeiner, Clemens; Periwal, Priyanka; Baron, Thierry; Bertagnolli, Emmerich; Lugstein, Alois

    2014-11-12

    The combined capabilities of both a nonplanar design and nonconventional carrier injection mechanisms are subject to recent scientific investigations to overcome the limitations of silicon metal oxide semiconductor field effect transistors. In this Letter, we present a multimode field effect transistors device using silicon nanowires that feature an axial n-type/intrinsic doping junction. A heterostructural device design is achieved by employing a self-aligned nickel-silicide source contact. The polymorph operation of the dual-gate device enabling the configuration of one p- and two n-type transistor modes is demonstrated. Not only the type but also the carrier injection mode can be altered by appropriate biasing of the two gate terminals or by inverting the drain bias. With a combined band-to-band and Schottky tunneling mechanism, in p-type mode a subthreshold swing as low as 143 mV/dec and an ON/OFF ratio of up to 10(4) is found. As the device operates in forward bias, a nonconventional tunneling transistor is realized, enabling an effective suppression of ambipolarity. Depending on the drain bias, two different n-type modes are distinguishable. The carrier injection is dominated by thermionic emission in forward bias with a maximum ON/OFF ratio of up to 10(7) whereas in reverse bias a Schottky tunneling mechanism dominates the carrier transport. PMID:25303290

  12. Investigation on a compact in-line multimode-single-mode-multimode fiber structure

    NASA Astrophysics Data System (ADS)

    Yin, Bin; Li, Yang; Liu, Zhi-bo; Feng, Suchun; Bai, Yunlong; Xu, Yao; Jian, Shuisheng

    2016-06-01

    We carried out a detailed investigation on a compact in-line multimode single-mode multimode (MSM) fiber structure. Both theoretical modal and experimental setup were established to demonstrate the transmission characteristics and the corresponding responses of the applied strain and temperature. The proposed structure simply involves a section of the single-mode fiber (SMF) spliced to two sections of multimode fiber (MMF) and lead-in and lead-out SMFs. The excited environment-sensitive cladding modes together with the fundamental mode in the central SMF form a typical Mach-Zehnder interferometer (MZI). We analyzed the transmission characteristics of the different length of the middle SMF and the MMF in detail. In the experiment, we obtained the extinction ratio of the MSM fiber structure based MZI comb spectrum which was up to 20 dB, and sensitivities of 0.7096 pm/με (0-2000 με) and 44.12 pm/°C (10-70 °C), which proved the potential sensing applications of the proposed fiber structure.

  13. Expectations predict chronic pain treatment outcomes.

    PubMed

    Cormier, Stéphanie; Lavigne, Geneviève L; Choinière, Manon; Rainville, Pierre

    2016-02-01

    Accumulating evidence suggests an association between patient pretreatment expectations and numerous health outcomes. However, it remains unclear if and how expectations relate to outcomes after treatments in multidisciplinary pain programs. The present study aims at investigating the predictive association between expectations and clinical outcomes in a large database of chronic pain patients. In this observational cohort study, participants were 2272 patients treated in one of 3 university-affiliated multidisciplinary pain treatment centers. All patients received personalized care, including medical, psychological, and/or physical interventions. Patient expectations regarding pain relief and improvements in quality of life and functioning were measured before the first visit to the pain centers and served as predictor variables. Changes in pain intensity, depressive symptoms, pain interference, and tendency to catastrophize, as well as satisfaction with pain treatment and global impressions of change at 6-month follow-up, were considered as treatment outcomes. Structural equation modeling analyses showed significant positive relationships between expectations and most clinical outcomes, and this association was largely mediated by patients' global impressions of change. Similar patterns of relationships between variables were also observed in various subgroups of patients based on sex, age, pain duration, and pain classification. Such results emphasize the relevance of patient expectations as a determinant of outcomes in multimodal pain treatment programs. Furthermore, the results suggest that superior clinical outcomes are observed in individuals who expect high positive outcomes as a result of treatment.

  14. Multimodal analgesia versus traditional opiate based analgesia after cardiac surgery, a randomized controlled trial

    PubMed Central

    2014-01-01

    Background To evaluate if an opiate sparing multimodal regimen of dexamethasone, gabapentin, ibuprofen and paracetamol had better analgesic effect, less side effects and was safe compared to a traditional morphine and paracetamol regimen after cardiac surgery. Methods Open-label, prospective randomized controlled trial. 180 patients undergoing cardiac procedures through median sternotomy, were included in the period march 2007- August 2009. 151 patients were available for analysis. Pain was assessed with the 11-numeric rating scale (11-NRS). Results Patients in the multimodal group demonstrated significantly lower average pain scores from the day of surgery throughout the third postoperative day. Extensive nausea and vomiting, was found in no patient in the multimodal group but in 13 patients in the morphine group, p < 0.001. Postoperative rise in individual creatinine levels demonstrated a non-significant rise in the multimodal group, 33.0±53.4 vs. 19.9±48.5, p = 0.133. Patients in the multimodal group suffered less major in-hospital events in crude numbers: myocardial infarction (MI) (1 vs. 2, p = 0.54), stroke (0 vs. 3, p = 0.075), dialysis (1 vs. 2, p = 0.54), and gastrointestinal (GI) bleeding (0 vs. 1, p = 0.31). 30-day mortality was 1 vs. 2, p = 0.54. Conclusions In patients undergoing cardiac surgery, a multimodal regimen offered significantly better analgesia than a traditional opiate regimen. Nausea and vomiting complaints were significantly reduced. No safety issues were observed with the multimodal regimen. Trial registration Clinicaltrials.gov identifier: NCT01966172 PMID:24650125

  15. A simultaneous multimodal imaging system for tissue functional parameters

    NASA Astrophysics Data System (ADS)

    Ren, Wenqi; Zhang, Zhiwu; Wu, Qiang; Zhang, Shiwu; Xu, Ronald

    2014-02-01

    Simultaneous and quantitative assessment of skin functional characteristics in different modalities will facilitate diagnosis and therapy in many clinical applications such as wound healing. However, many existing clinical practices and multimodal imaging systems are subjective, qualitative, sequential for multimodal data collection, and need co-registration between different modalities. To overcome these limitations, we developed a multimodal imaging system for quantitative, non-invasive, and simultaneous imaging of cutaneous tissue oxygenation and blood perfusion parameters. The imaging system integrated multispectral and laser speckle imaging technologies into one experimental setup. A Labview interface was developed for equipment control, synchronization, and image acquisition. Advanced algorithms based on a wide gap second derivative reflectometry and laser speckle contrast analysis (LASCA) were developed for accurate reconstruction of tissue oxygenation and blood perfusion respectively. Quantitative calibration experiments and a new style of skinsimulating phantom were designed to verify the accuracy and reliability of the imaging system. The experimental results were compared with a Moor tissue oxygenation and perfusion monitor. For In vivo testing, a post-occlusion reactive hyperemia (PORH) procedure in human subject and an ongoing wound healing monitoring experiment using dorsal skinfold chamber models were conducted to validate the usability of our system for dynamic detection of oxygenation and perfusion parameters. In this study, we have not only setup an advanced multimodal imaging system for cutaneous tissue oxygenation and perfusion parameters but also elucidated its potential for wound healing assessment in clinical practice.

  16. Multimodal Friction Ignition Tester

    NASA Technical Reports Server (NTRS)

    Davis, Eddie; Howard, Bill; Herald, Stephen

    2009-01-01

    The multimodal friction ignition tester (MFIT) is a testbed for experiments on the thermal and mechanical effects of friction on material specimens in pressurized, oxygen-rich atmospheres. In simplest terms, a test involves recording sensory data while rubbing two specimens against each other at a controlled normal force, with either a random stroke or a sinusoidal stroke having controlled amplitude and frequency. The term multimodal in the full name of the apparatus refers to a capability for imposing any combination of widely ranging values of the atmospheric pressure, atmospheric oxygen content, stroke length, stroke frequency, and normal force. The MFIT was designed especially for studying the tendency toward heating and combustion of nonmetallic composite materials and the fretting of metals subjected to dynamic (vibrational) friction forces in the presence of liquid oxygen or pressurized gaseous oxygen test conditions approximating conditions expected to be encountered in proposed composite material oxygen tanks aboard aircraft and spacecraft in flight. The MFIT includes a stainless-steel pressure vessel capable of retaining the required test atmosphere. Mounted atop the vessel is a pneumatic cylinder containing a piston for exerting the specified normal force between the two specimens. Through a shaft seal, the piston shaft extends downward into the vessel. One of the specimens is mounted on a block, denoted the pressure block, at the lower end of the piston shaft. This specimen is pressed down against the other specimen, which is mounted in a recess in another block, denoted the slip block, that can be moved horizontally but not vertically. The slip block is driven in reciprocating horizontal motion by an electrodynamic vibration exciter outside the pressure vessel. The armature of the electrodynamic exciter is connected to the slip block via a horizontal shaft that extends into the pressure vessel via a second shaft seal. The reciprocating horizontal

  17. Perioperative Pain Management in Total Hip Arthroplasty: Korean Hip Society Guidelines

    PubMed Central

    Kim, Yeesuk; Cho, Hong-Man; Park, Kyung-Soon; Yoon, Pil Whan; Nho, Jae-Hwi; Kim, Sang-Min; Lee, Kyung-Jae; Moon, Kyong-Ho

    2016-01-01

    Effective perioperative pain management techniques and accelerated rehabilitation programs can improve health-related quality of life and functional status of patients after total hip arthroplasty. Traditionally, postoperative analgesia following arthroplasty was provided by intravenous patient-controlled analgesia or epidural analgesia. Recently, peripheral nerve blockade has emerged alternative analgesic approach. Multimodal analgesia strategy combines analgesics with different mechanisms of action to improve pain management. Intraoperative periarticular injection of multimodal drugs is one of the most important procedures in perioperative pain control for total hip arthroplasty. The goal of this review article is to provide a concise overview of the principles of multimodal pain management regimens as a practical guide for the perioperative pain management for total hip arthroplasty. PMID:27536639

  18. Perioperative Pain Management in Total Hip Arthroplasty: Korean Hip Society Guidelines.

    PubMed

    Min, Byung-Woo; Kim, Yeesuk; Cho, Hong-Man; Park, Kyung-Soon; Yoon, Pil Whan; Nho, Jae-Hwi; Kim, Sang-Min; Lee, Kyung-Jae; Moon, Kyong-Ho

    2016-03-01

    Effective perioperative pain management techniques and accelerated rehabilitation programs can improve health-related quality of life and functional status of patients after total hip arthroplasty. Traditionally, postoperative analgesia following arthroplasty was provided by intravenous patient-controlled analgesia or epidural analgesia. Recently, peripheral nerve blockade has emerged alternative analgesic approach. Multimodal analgesia strategy combines analgesics with different mechanisms of action to improve pain management. Intraoperative periarticular injection of multimodal drugs is one of the most important procedures in perioperative pain control for total hip arthroplasty. The goal of this review article is to provide a concise overview of the principles of multimodal pain management regimens as a practical guide for the perioperative pain management for total hip arthroplasty. PMID:27536639

  19. Multimodal Neuroelectric Interface Development

    NASA Technical Reports Server (NTRS)

    Trejo, Leonard J.; Wheeler, Kevin R.; Jorgensen, Charles C.; Totah, Joseph (Technical Monitor)

    2001-01-01

    This project aims to improve performance of NASA missions by developing multimodal neuroelectric technologies for augmented human-system interaction. Neuroelectric technologies will add completely new modes of interaction that operate in parallel with keyboards, speech, or other manual controls, thereby increasing the bandwidth of human-system interaction. We recently demonstrated the feasibility of real-time electromyographic (EMG) pattern recognition for a direct neuroelectric human-computer interface. We recorded EMG signals from an elastic sleeve with dry electrodes, while a human subject performed a range of discrete gestures. A machine-teaming algorithm was trained to recognize the EMG patterns associated with the gestures and map them to control signals. Successful applications now include piloting two Class 4 aircraft simulations (F-15 and 757) and entering data with a "virtual" numeric keyboard. Current research focuses on on-line adaptation of EMG sensing and processing and recognition of continuous gestures. We are also extending this on-line pattern recognition methodology to electroencephalographic (EEG) signals. This will allow us to bypass muscle activity and draw control signals directly from the human brain. Our system can reliably detect P-rhythm (a periodic EEG signal from motor cortex in the 10 Hz range) with a lightweight headset containing saline-soaked sponge electrodes. The data show that EEG p-rhythm can be modulated by real and imaginary motions. Current research focuses on using biofeedback to train of human subjects to modulate EEG rhythms on demand, and to examine interactions of EEG-based control with EMG-based and manual control. Viewgraphs on these neuroelectric technologies are also included.

  20. Locating the Semiotic Power of Multimodality

    ERIC Educational Resources Information Center

    Hull, Glynda A.; Nelson, Mark Evan

    2005-01-01

    This article reports research that attempts to characterize what is powerful about digital multimodal texts. Building from recent theoretical work on understanding the workings and implications of multimodal communication, the authors call for a continuing empirical investigation into the roles that digital multimodal texts play in real-world…

  1. Multimodal Hip Hop Productions as Media Literacies

    ERIC Educational Resources Information Center

    Turner, K. C. Nat

    2012-01-01

    This study draws on ethnographic data from a year-long multimodal media production (MMP) course and the experience of an African American female adolescent who used the production of multimodal Hip Hop texts to express her creativity and growing socially conscious view of the world. The study demonstrates how students made meaning multimodally and…

  2. Recent Advances in Postoperative Pain Management

    PubMed Central

    Vadivelu, Nalini; Mitra, Sukanya; Narayan, Deepak

    2010-01-01

    Good pain control after surgery is important to prevent negative outcomes such as tachycardia, hypertension, myocardial ischemia, decrease in alveolar ventilation, and poor wound healing. Exacerbations of acute pain can lead to neural sensitization and release of mediators both peripherally and centrally. Clinical wind up occurs from the processes of N-Methyl D-Aspartate (NMDA) activation, wind up central sensitization, long-term potentiation of pain (LTP), and transcription-dependent sensitization. Advances in the knowledge of molecular mechanisms have led to the development of multimodal analgesia and new pharmaceutical products to treat postoperative pain. The new pharmacological products to treat postoperative pain include extended-release epidural morphine and analgesic adjuvants such as capsaicin, ketamine, gabapentin, pregabalin dexmetomidine, and tapentadol. Newer postoperative patient-controlled analgesia (PCA) in modes such as intranasal, regional, transdermal, and pulmonary presents another interesting avenue of development. PMID:20351978

  3. Committee Opinion No 673: Persistent Vulvar Pain.

    PubMed

    2016-09-01

    Persistent vulvar pain is a complex disorder that frequently is frustrating to the patient and the clinician. It can be difficult to treat and rapid resolution is unusual, even with appropriate therapy. Vulvar pain can be caused by a specific disorder or it can be idiopathic. Idiopathic vulvar pain is classified as vulvodynia. Although optimal treatment remains unclear, consider an individualized, multidisciplinary approach to address all physical and emotional aspects possibly attributable to vulvodynia. Specialists who may need to be involved include sexual counselors, clinical psychologists, physical therapists, and pain specialists. Patients may perceive this approach to mean the practitioner does not believe their pain is "real"; thus, it is important to begin any treatment approach with a detailed discussion, including an explanation of the diagnosis and determination of realistic treatment goals. Future research should aim at evaluating a multimodal approach in the treatment of vulvodynia, along with more research on the etiologies of vulvodynia. PMID:27548558

  4. Pain, Catastrophizing, and Depression in Chronic Prostatitis/Chronic Pelvic Pain Syndrome

    PubMed Central

    Kwon, Jong Kyou

    2013-01-01

    Persistent and disabling pain is the hallmark of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). However, disease severity (as measured by objective indexes such as those that use radiography or serology) is only marginally related to patients' reports of pain severity, and pain-related presentation can differ widely among individuals with CP/CPPS. Increasing evidence in support of the biopsychosocial model of pain suggests that cognitive and emotional processes are crucial contributors to inter-individual differences in the perception and impact of pain. This review describes the growing body of literature relating depression and catastrophizing to the experience of pain and pain-related sequelae in CP/CPPS. Depression and catastrophizing are consistently associated with the reported severity of pain, sensitivity to pain, physical disability, poor treatment outcomes, and inflammatory disease activity and potentially with early mortality. A variety of pathways, from cognitive to behavioral to neurophysiological, seem to mediate these deleterious effects. Collectively, depression and catastrophizing are critically important variables in understanding the experience of pain in patients with CP/CPPS. Pain, depression, and catastrophizing might all be uniquely important therapeutic targets in the multimodal management of a range of such conditions. PMID:23869268

  5. Pain Management in Four-Limb Amputation: A Case Report.

    PubMed

    Warner, Nafisseh S; Warner, Matthew A; Moeschler, Susan M; Hoelzer, Bryan C

    2015-09-01

    Acute pain following amputation can be challenging to treat due to multiple underlying mechanisms and variable clinical responses to treatment. Furthermore, poorly controlled preoperative pain is a risk factor for developing chronic pain. Evidence suggests that epidural analgesia and peripheral nerve blockade may decrease the severity of residual limb pain and the prevalence of phantom pain after lower extremity amputation. We present the perioperative analgesic management of a patient with gangrene of the bilateral upper and lower extremities as a result of septic shock and prolonged vasopressor administration who underwent four-limb amputation in a single procedure. A multimodal analgesic regimen was utilized, including titration of preoperative opioid and neuropathic pain agents, perioperative intravenous, epidural and peripheral nerve catheter infusions, and postoperative oral medication titration. More than 8 months postoperatively, the patient has satisfactory pain control with no evidence for phantom limb pain. To our knowledge, there have been no publications to date concerning analgesic regimens in four-limb amputation.

  6. Effect of multimodal stimulus presentation on recall.

    PubMed

    Kobus, D A; Moses, J D; Bloom, F A

    1994-02-01

    This study was conducted to investigate how the mode of stimulus presentation affects recall in the classroom environment. 289 undergraduates were randomly assigned to one of 7 experimental groups. All subjects were presented the same stimuli in one of 7 possible modes: (1) Printed Word, (2) Spoken Word, (3) Picture, (4) Printed Word + Spoken Word, (5) Picture + Spoken Word, (6) Picture + Printed Word, and (7) Printed Word, Picture + Spoken Word. 30 words, 6 from each of 5 categories, were presented to each group. A new stimulus was presented every 5 sec. Subjects were to recall (in writing) as many stimuli as possible in 5 min. regardless of order. One-way between groups analyses of variance were conducted on recall and cluster index scores. A significant main effect of mode of presentation showed that recall was best for the Picture or multimodal group (Printed Word, Picture + Spoken Word). Groups receiving only the spoken or printed word showed significantly poorer recall than the multimodal groups. No statistically significant differences between groups were found on the cluster index score. It appears that the simultaneous presentation of redundant stimuli in multiple modalities does support the multiple-resource hypothesis by displaying enhanced recall when information is available from multiple attentional resources.

  7. Analysis of multimode fiber bundles for endoscopic spectral-domain optical coherence tomography

    PubMed Central

    Risi, Matthew D.; Makhlouf, Houssine; Rouse, Andrew R.; Gmitro, Arthur F.

    2016-01-01

    A theoretical analysis of the use of a fiber bundle in spectral-domain optical coherence tomography (OCT) systems is presented. The fiber bundle enables a flexible endoscopic design and provides fast, parallelized acquisition of the OCT data. However, the multimode characteristic of the fibers in the fiber bundle affects the depth sensitivity of the imaging system. A description of light interference in a multimode fiber is presented along with numerical simulations and experimental studies to illustrate the theoretical analysis. PMID:25967012

  8. Back Pain

    MedlinePlus

    ... Oh, my aching back!", you are not alone. Back pain is one of the most common medical problems, ... 10 people at some point during their lives. Back pain can range from a dull, constant ache to ...

  9. [Oral pain].

    PubMed

    Benslama, Lotfi

    2002-02-15

    Pain, a major symptom of stomatological disease, usually leads to a specialist consultation. Most commonly it is caused by dental caries and differs in nature and in intensity according to the stage of disease: dentinitis, pulpitis, desmodontitis and dental abscess. Added to this is peridental pain and the pre- and post-operative pains related to these diseases. Almost all oral-maxillary pathology is painful, be it boney such as in osteomyelitis and fractures, mucosal in gingivo-stomatitis and aphthous ulcers, or tumourous. However, besides the "multidisciplinary" facial pains such as facial neuralgia and vascular pain, two pain syndromes are specific to stomatology: pain of the tempero-mandibular joint associated with problems of the bite and glossodynia, a very common somatic expression of psychological problems.

  10. Pain Management

    MedlinePlus

    ... the brain played a role in producing the perception of pain. In the 19th century, physician-scientists ... they are experiencing. Discoveries of differences in pain perceptions and responses to treatment by gender has have ...

  11. Finger pain

    MedlinePlus

    Pain - finger ... Nearly everyone has had finger pain at some time. You may have: Tenderness Burning Stiffness Numbness Tingling Coldness Swelling Change in skin color Redness Many conditions, such ...

  12. Pain Assessment

    MedlinePlus

    ... as a result of the pain, and the nature of other medical and psychiatric problems, should be ... information helps the health care provider understand the nature of the pain or the potential benefits of ...

  13. Breast pain

    MedlinePlus

    Pain - breast; Mastalgia; Mastodynia; Breast tenderness ... There are many possible causes for breast pain. For example, hormone level changes from menstruation or pregnancy often cause breast tenderness. Some swelling and tenderness just before your period ...

  14. Patellofemoral Pain.

    PubMed

    Dutton, Rebecca A; Khadavi, Michael J; Fredericson, Michael

    2016-02-01

    Patellofemoral pain is characterized by insidious onset anterior knee pain that is exaggerated under conditions of increased patellofemoral joint stress. A variety of risk factors may contribute to the development of patellofemoral pain. It is critical that the history and physical examination elucidate those risk factors specific to an individual in order to prescribe an appropriate and customized treatment plan. This article aims to review the epidemiology, risk factors, diagnosis, and management of patellofemoral pain. PMID:26616176

  15. Patellofemoral Pain.

    PubMed

    Dutton, Rebecca A; Khadavi, Michael J; Fredericson, Michael

    2016-02-01

    Patellofemoral pain is characterized by insidious onset anterior knee pain that is exaggerated under conditions of increased patellofemoral joint stress. A variety of risk factors may contribute to the development of patellofemoral pain. It is critical that the history and physical examination elucidate those risk factors specific to an individual in order to prescribe an appropriate and customized treatment plan. This article aims to review the epidemiology, risk factors, diagnosis, and management of patellofemoral pain.

  16. Multimodal imaging of ischemic wounds

    NASA Astrophysics Data System (ADS)

    Zhang, Shiwu; Gnyawali, Surya; Huang, Jiwei; Liu, Peng; Gordillo, Gayle; Sen, Chandan K.; Xu, Ronald

    2012-12-01

    The wound healing process involves the reparative phases of inflammation, proliferation, and remodeling. Interrupting any of these phases may result in chronically unhealed wounds, amputation, or even patient death. Quantitative assessment of wound tissue ischemia, perfusion, and inflammation provides critical information for appropriate detection, staging, and treatment of chronic wounds. However, no method is available for noninvasive, simultaneous, and quantitative imaging of these tissue parameters. We integrated hyperspectral, laser speckle, and thermographic imaging modalities into a single setup for multimodal assessment of tissue oxygenation, perfusion, and inflammation characteristics. Advanced algorithms were developed for accurate reconstruction of wound oxygenation and appropriate co-registration between different imaging modalities. The multimodal wound imaging system was validated by an ongoing clinical trials approved by OSU IRB. In the clinical trial, a wound of 3mm in diameter was introduced on a healthy subject's lower extremity and the healing process was serially monitored by the multimodal imaging setup. Our experiments demonstrated the clinical usability of multimodal wound imaging.

  17. Multimodal Revision Techniques in Webtexts

    ERIC Educational Resources Information Center

    Ball, Cheryl E.

    2014-01-01

    This article examines how an online scholarly journal, "Kairos: Rhetoric, Technology, Pedagogy," mentors authors to revise their webtexts (interactive, digital media scholarship) for publication. Using an editorial pedagogy in which multimodal and rhetorical genre theories are merged with revision techniques found in process-based…

  18. Multimodality as a Sociolinguistic Resource

    ERIC Educational Resources Information Center

    Collister, Lauren Brittany

    2013-01-01

    This work explores the use of multimodal communication in a community of expert "World of Warcraft"® players and its impact on politeness, identity, and relationships. Players in the community regularly communicated using three linguistic modes quasi-simultaneously: text chat, voice chat, and face-to-face interaction. Using the…

  19. Multi-Modality Phantom Development

    SciTech Connect

    Huber, Jennifer S.; Peng, Qiyu; Moses, William W.

    2009-03-20

    Multi-modality imaging has an increasing role in the diagnosis and treatment of a large number of diseases, particularly if both functional and anatomical information are acquired and accurately co-registered. Hence, there is a resulting need for multi modality phantoms in order to validate image co-registration and calibrate the imaging systems. We present our PET-ultrasound phantom development, including PET and ultrasound images of a simple prostate phantom. We use agar and gelatin mixed with a radioactive solution. We also present our development of custom multi-modality phantoms that are compatible with PET, transrectal ultrasound (TRUS), MRI and CT imaging. We describe both our selection of tissue mimicking materials and phantom construction procedures. These custom PET-TRUS-CT-MRI prostate phantoms use agargelatin radioactive mixtures with additional contrast agents and preservatives. We show multi-modality images of these custom prostate phantoms, as well as discuss phantom construction alternatives. Although we are currently focused on prostate imaging, this phantom development is applicable to many multi-modality imaging applications.

  20. Pain control.

    PubMed

    Boey, W K

    1991-01-01

    There are two components to the perception of pain; the 'sensory' and the 'reactive'. Psychological factors control the latter. Pain research is rapidly advancing: the discovery of endorphins and opioid receptors, the appreciation of the psychological component of pain and the multidisciplinary approach to chronic pain are major advances. Pain can be classified as acute or chronic. Acute pain is easy to diagnose, the cause of pain obvious and the treatment logical, chronic pain has a greater psychological component, is difficult to diagnose and treatment is often empirical. Methods of pain control include drugs, injection techniques, electro stimulation, non invasive therapies, denervation procedures and palliative procedures. A multidisciplinary approach and a combination of methods is necessary to treat chronic pain. Spinal opioids, radiofrequency thermocoagulation, intrapleural bupivacaine, cryoanalgesia and patient controlled analgesia are recent advances in pain control. However, most pain can be controlled adequately with simple methods; what is essential is the interest and commitment of the physician towards achieving optimum therapeutics. PMID:1674199

  1. Chronic pain.

    PubMed

    Russo, C M; Brose, W G

    1998-01-01

    Chronic pain is an emotional experience and is defined as pain lasting greater than six months. It is important to understand the neurophysiology of pain in order to treat it. Nociceptors in the periphery travel to the substantia gelatinosa of the spinal cord while secondary and tertiary afferents transmit information from the dorsal horn to the brain. Modification of pain information may take place in these ascending pathways or in descending pathways. Treatment of chronic pain is most successful when it is approached in a multidisciplinary fashion with the focus not only on treatment of underlying etiology, but also on the secondary impacts of pain on the patient's life. The management of chronic pain requires special expertise. Most of the experts in chronic pain assessment and management organize themselves into pain treatment centers. These centers vary widely in their approach to the problem. The most sophisticated is a multidisciplinary center that is university-based and includes teaching and research. Treatment of chronic pain includes a variety of medications, psychological support, and rehabilitation. Multidisciplinary pain management is also an integral part of the palliative care and hospice concept used to treat cancer pain.

  2. Acute pain management in the opioid-tolerant patient.

    PubMed

    Bourne, Nicola

    The main goals in treating acute pain in opioid-tolerant patients are effective pain relief and prevention of withdrawal symptoms. This article provides an overview of the issues that practitioners need to consider when caring for potential and actual opioid-tolerant patients experiencing acute pain, for example following surgery or injury. It highlights the importance of a multimodal analgesic approach to pain control and the prevention of withdrawal. It defines the terminology used in managing opioid-tolerant patients in order to allay healthcare professionals' misconceptions.

  3. Improving patient outcomes through advanced pain management techniques in total hip and knee arthroplasty.

    PubMed

    Barrington, John W; Dalury, David F; Emerson, Roger H; Hawkins, Richard J; Joshi, Girish P; Stulberg, Bernard N

    2013-10-01

    Pain following orthopedic surgery is common and often suboptimally managed, with many patients reporting acute moderate to severe pain following surgery. Opioids are often used to manage this pain, yet this can result in significant side effects and complications, including constipation, nausea, vomiting, respiratory distress, and other central nervous system issues. Multimodal therapy that includes surgical site infiltration with extended release local anesthetic has been seen as a new way to minimize this pain for patients, which can result in improved quality of life and shorter length of hospital stay. This article examines the use of bupivacaine liposome injectable suspension (EXPAREL®; Pacira Pharmaceuticals, Inc., San Diego, California), a non-opioid product for pain management. Liposomal bupivacaine uses DepoFoam® technology that allows for the extended release of injected drugs. When used as the foundation of a multimodal regimen, it is effective in reducing postsurgical pain for up to 72 hours while reducing the need for opioids for pain relief.

  4. Dynamic bending compensation while focusing through a multimode fiber.

    PubMed

    Farahi, Salma; Ziegler, David; Papadopoulos, Ioannis N; Psaltis, Demetri; Moser, Christophe

    2013-09-23

    Multimode fiber endoscopes have recently been shown to provide sub-micrometer resolution, however, imaging through a multimode fiber is highly sensitive to bending. Here we describe the implementation of a coherent beacon source placed at the distal tip of the multimode fiber, which can be used to compensate for the effects of bending. In the first part of this paper, we show that a diffraction limited focused spot can be generated at the distal tip of the multimode fiber using the beacon. In the second part, we demonstrate focusing even when the fiber is bent by dynamically compensating for it. The speckle pattern at the proximal fiber end, generated by the beacon source placed at its distal end, is highly dependent on the fiber conformation. We experimentally show that by intensity correlation, it is possible to identify the fiber conformation and maintain a focus spot while the fiber is bent over a certain range. Once the fiber configuration is determined, previously calibrated phase patterns could be stored for each fiber conformation and used to scan the distal spot and perform imaging.

  5. Temporomandibular pain

    PubMed Central

    Prasad, S Raghavendra; Kumar, N Ravi; Shruthi, HR; Kalavathi, SD

    2016-01-01

    Temporomandibular joint pain has various medical and dental etiological factors. The etiology of the temporomandibular joint pain is enigmatic, no single etiological factor is regarded as the cause. Its distribution is also not confined to a single area. This article presents the basic etiologic factors, its epidemiology, distribution of pain, classification of patients and the psychosocial behavior of patients suffering with temporomandibular pain. As overwhelming majority of medical and dental conditions/issues related to etiology of temporomandibular pain in patients have traditionally been presented and interpreted from the clinician's point of view. PMID:27601822

  6. Temporomandibular pain

    PubMed Central

    Prasad, S Raghavendra; Kumar, N Ravi; Shruthi, HR; Kalavathi, SD

    2016-01-01

    Temporomandibular joint pain has various medical and dental etiological factors. The etiology of the temporomandibular joint pain is enigmatic, no single etiological factor is regarded as the cause. Its distribution is also not confined to a single area. This article presents the basic etiologic factors, its epidemiology, distribution of pain, classification of patients and the psychosocial behavior of patients suffering with temporomandibular pain. As overwhelming majority of medical and dental conditions/issues related to etiology of temporomandibular pain in patients have traditionally been presented and interpreted from the clinician's point of view.

  7. Temporomandibular pain.

    PubMed

    Prasad, S Raghavendra; Kumar, N Ravi; Shruthi, H R; Kalavathi, S D

    2016-01-01

    Temporomandibular joint pain has various medical and dental etiological factors. The etiology of the temporomandibular joint pain is enigmatic, no single etiological factor is regarded as the cause. Its distribution is also not confined to a single area. This article presents the basic etiologic factors, its epidemiology, distribution of pain, classification of patients and the psychosocial behavior of patients suffering with temporomandibular pain. As overwhelming majority of medical and dental conditions/issues related to etiology of temporomandibular pain in patients have traditionally been presented and interpreted from the clinician's point of view. PMID:27601822

  8. Connecting multimodality in human communication

    PubMed Central

    Regenbogen, Christina; Habel, Ute; Kellermann, Thilo

    2013-01-01

    DCM analysis instead showed a pronounced top-down control. Remarkably, all connections from the dmPFC to the three other regions were modulated by the experimental conditions. This observation is in line with the presumed role of the dmPFC in the allocation of attention. In contrary, all incoming connections to the AG were modulated, indicating its key role in integrating multimodal information and supporting comprehension. Notably, the input from the FFG to the AG was enhanced when facial expressions conveyed emotional information. These findings serve as preliminary results in understanding network dynamics in human emotional communication and empathy. PMID:24265613

  9. Learned Resourcefulness and the Long-Term Benefits of a Chronic Pain Management Program

    ERIC Educational Resources Information Center

    Kennett, Deborah J.; O'Hagan, Fergal T.; Cezer, Diego

    2008-01-01

    A concurrent mixed methods approach was used to understand how learned resourcefulness empowers individuals. After completing Rosenbaum's Self-Control Schedule (SCS) measuring resourcefulness, 16 past clients of a multimodal pain clinic were interviewed about the kinds of pain-coping strategies they were practicing from the program. Constant…

  10. Persistence behavior of chronic low back pain patients in an acute pain situation.

    PubMed

    Schmidt, A J; Brands, A M

    1986-01-01

    The test behavior of 24 chronic low back pain patients was compared with the behavior of 24 healthy control Ss., matched for age and sex, in an experimental, acute pain situation (cold pressor-test). Chronic low back pain patients showed poorer persistence behavior and reported more pain. Thus, elements of typical chronic low back pain behavior were also present in an acute pain situation. These findings are discussed within the framework of stimulus-generalization theory. In addition, the effect of different coping strategies on pain tolerance was reconfirmed. The chronic low back pain group and the control group did not cope differently.

  11. A randomized, double-blind, positive-controlled, 3-way cross-over human experimental pain study of a TRPV1 antagonist (V116517) in healthy volunteers and comparison with preclinical profile.

    PubMed

    Arendt-Nielsen, Lars; Harris, Steve; Whiteside, Garth T; Hummel, Michele; Knappenberger, Terri; OʼKeefe, Sarah; Kapil, Ram; Kyle, Don

    2016-09-01

    This experimental, translational, experimental pain, single-center, randomized, double-blind, single-dose, 3-treatment, 3-period cross-over proof-of-concept volunteer trial studied the efficacy of a novel TRPV1 antagonist (V116517) on capsaicin- and UV-B-induced hyperalgesia. Heat and pressure pain thresholds, von Frey stimulus-response functions, and neurogenic inflammation were assessed together with safety. Each treatment period was 4 days. The 3 single oral treatments were 300 mg V116517, 400 mg celecoxib (a COX-2 inhibitor), and placebo. The heat pain detection and tolerance thresholds were increased significantly (P < 0.0001) by V116517. Heat pain detection and tolerance thresholds showed significantly less capsaicin hyperalgesia after V116517 (P = 0.004 and P < 0.0001, respectively). Celecoxib reduced UV-B-provoked pressure pain sensitization (P = 0.01). Laser Doppler flowmetry and erythema index after UV-B were significantly (P < 0.0001) reduced by celecoxib. Stimulus-response function in capsaicin-treated areas showed significant differences between both celecoxib and placebo and between V116517 and placebo. The body temperature showed no change, and no side effects were reported for any of the treatments. The TRPV1 antagonists and the COX-2 inhibitor showed different antihyperalgesic profiles indicating different clinical targets. In addition, the preclinical profile of V116517 in rat models of UV-B and capsaicin-induced hypersensitivity was compared with the human experimental data and overall demonstrated an alignment between 2 of the 3 end points tested. The TRPV1 antagonist showed a potent antihyperalgesic action without changing the body temperature but heat analgesia may be a potential safety issue. PMID:27168361

  12. Overview of Total Knee Arthroplasty and Modern Pain Control Strategies.

    PubMed

    Lavie, Lacey Giambelluca; Fox, M Patricia; Dasa, Vinod

    2016-11-01

    Perioperative pain management of total knee arthroplasty (TKA) remains a challenge for physicians and anesthesiologists. Reducing postoperative pain is an essential component of patient satisfaction, functional outcomes, and hospital length of stay. Multimodal pain management regimens have been demonstrated to be superior to monotherapy in achieving adequate pain control, as well as an effective method of limiting side effects of analgesics. In the present investigation, we present literature published over the last year relating to new advancements in perioperative pain management for TKA. While it is widely accepted that methods including peripheral nerve blocks and local anesthetic injections are essential to pain protocols, there is still conflicting evidence over what modalities provide superior relief. The incorporation of cryoneurolysis preoperatively is a new modality which has been incorporated and has been shown to improve pain control in patients undergoing TKA.

  13. Present-day challenges and future solutions in postoperative pain management: results from PainForum 2014

    PubMed Central

    Kuusniemi, Kristiina; Pöyhiä, Reino

    2016-01-01

    This paper is a summary of presentations on postoperative pain control by the authors at the 2014 PainForum meeting in People’s Republic of China. Postoperative pain is often untreated or undertreated and may lead to subsequent chronic pain syndromes. As more procedures migrate to the outpatient setting, postoperative pain control will become increasingly more challenging. Evidence-based guidelines for postoperative pain control recommend pain assessment using validated tools on a consistent basis. In this regard, consistency may be more important than the specific tool selected. Many hospitals have introduced a multidisciplinary acute pain service (APS), which has been associated with improved patient satisfaction and fewer adverse events. Patient education is an important component of postoperative pain control, which may be most effective when clinicians chose a multimodal approach, such as paracetamol (acetaminophen) and opioids. Opioids are a mainstay of postoperative pain control but require careful monitoring and management of side effects, such as nausea, vomiting, dizziness, and somnolence. Opioids may be administered using patient-controlled analgesia systems. Protocols for postoperative pain control can be very helpful to establish benchmarks for pain management and assure that clinicians adhere to evidence-based standards. The future of postoperative pain control around the world will likely involve more and better established APSs and greater communication between patients and clinicians about postoperative pain. The changes necessary to implement and move forward with APSs is not a single step but rather one of continuous improvement and ongoing change. PMID:26893579

  14. [Trends in world science and practice of pain treatment].

    PubMed

    Osipova, N A

    2014-01-01

    In recent days there are two main conceptions of the treatment of strong pain. The first conception is a system multimodal analgesia and the second is a multidisciplinary therapy including invasive techniques (local nervous blockades, neuroaxial blockades, neurostimulating or drug therapy with implanted systems etc.), physical, manual, and psychological effecting on peripheral and central nervous system. A physician (anaesthesiologist, oncologist, neurologist etc.) treats the pain according to interests of a patient. Multidisciplinary pain treatment, which is recommended by the American Pain Association, requires the use of special equipment for effecting on nervous system of the patient and contains conflict of interests of managers, medical workers, equipment providing companies and other parts of the multidisciplinary process. Therefore there is a risk that commercial benefit can get a main role in the process of pain treatment, but not interests of the patient. The "industrial" approach in the pain treatment is connected with many negative outcomes such as a minimizing of the role of pain science, increasing of complications risks due to invasive techniques of the pain relief etc. Therefore an objective analysis of pain treatment outcomes is needed Helsinki Declaration of a patient safety in surgery approved by European Society of Anaesthesiology in June, 2010 requires an accounting system of critical incidents, complications and assessment of outcomes in perioperative anaesthesiological practice. The same study is very actual for Russia especially to compare a safety of the system multimodal anaesthesia/analgesia and epidural blockades in major surgery.

  15. Fabrication of a Multimodal Microbubble Platform for Magnetic Resonance, Ultrasound and Fluorescence Imaging Application.

    PubMed

    Miao, Zhaohua; Guo, Caixin; Li, Zhenglin; Ke, Hengte; Dai, Zhifei

    2016-03-01

    Magnetic resonance (MR), ultrasound (US) and fluorescence imaging are the widely used diagnostic modalities for various experimental and clinical applications. A multimodal poly(lactic acid) microbubble (MB) integrated with the three imaging modalities was fabricated by adsorbing CdTe quantum dots (QDs) onto the surface and encapsulating superparamagnetic iron oxide (SPIO) nanoparticles into the core. The strong fluorescence of the multimodal MBs confirmed that QDs were successfully deposited onto the surface. The in vitro MRI contrasting capability of the multimodal MBs at various concentrations was evaluated by T2-weighted imaging. Furthermore, the in vitro and in vivo ultrasonography indicated that CdTe and SPIO-inclusive MBs maintained excellent ultrasound contrast property. These results implied that the nano-in-micro hybrid materials have the potential as a nanomedical platform for multimodal bioimaging.

  16. Inclusion of authorized deception in the informed consent process does not affect the magnitude of the placebo effect for experimentally induced pain.

    PubMed

    Martin, Andrea L; Katz, Joel

    2010-05-01

    The ethics of placebo research have been of paramount concern since the discovery of the phenomenon. To address these ethical concerns, Miller and colleagues (PLoS Med 2005 Sep;2(9):e262, 0853-0859) propose an alternate approach to placebo research, called "authorized deception", in which participants are alerted of the use of deception in the research prior to study enrollment and thus knowingly permit its use if they decide to participate. The present study sought to investigate the authorized deception methodology in experimentally induced placebo analgesia. The participants were randomly assigned to an authorized deception or non-authorized deception group. A commonly used protocol was employed wherein heat pain stimulation was surreptitiously lowered following the application of a placebo cream during a series of conditioning trials and the magnitude of the placebo effect was subsequently assessed in test trials for which the stimulus intensity was the same for both the placebo and control creams. Authorized deception did not have any negative impact on the magnitude of the placebo effect, recruitment and retention of participants, nor did it result in any significant psychological harm. The majority of participants who received this form of consent preferred it to the traditional approach in which the participants are not alerted to the presence of deception. These findings suggest that the use of authorized deception is a viable and ethically preferable alternative consent process for laboratory-based studies on placebo analgesia. Further studies are needed to examine the effect of authorized deception in clinical trials and other placebo research within a clinical setting.

  17. Male chronic pelvic pain: An update

    PubMed Central

    Smith, Christopher P.

    2016-01-01

    Introduction: Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) and interstitial cystitis/bladder pain syndrome collectively referred to as urologic CPPS (UCPPS) is defined by the absence of identifiable bacterial infection as a cause for the chronic pain and urinary symptoms. Methods: A PubMed search of all recent relevant articles using the keywords/phrases: CPPS, CPPS, and male pelvic pain, was conducted. Results: CPPS has a high worldwide prevalence and its negative impact on quality of life compares with or exceeds common chronic morbidities. Triggers include certain comestibles as well as psychosocial factors that promote catastrophizing and illness focused behavior. Several validated tools are currently available to help diagnose and direct targeted therapy. Treatment should begin with the most simple and least invasive based on the presenting clinical phenotype. Conclusions: Although no gold-standard treatment exists, a multidisciplinary approach with multimodal therapy gives the UCPPS patient the best chance of symptom relief. PMID:26941492

  18. Continuous verification using multimodal biometrics.

    PubMed

    Sim, Terence; Zhang, Sheng; Janakiraman, Rajkumar; Kumar, Sandeep

    2007-04-01

    Conventional verification systems, such as those controlling access to a secure room, do not usually require the user to reauthenticate himself for continued access to the protected resource. This may not be sufficient for high-security environments in which the protected resource needs to be continuously monitored for unauthorized use. In such cases, continuous verification is needed. In this paper, we present the theory, architecture, implementation, and performance of a multimodal biometrics verification system that continuously verifies the presence of a logged-in user. Two modalities are currently used--face and fingerprint--but our theory can be readily extended to include more modalities. We show that continuous verification imposes additional requirements on multimodal fusion when compared to conventional verification systems. We also argue that the usual performance metrics of false accept and false reject rates are insufficient yardsticks for continuous verification and propose new metrics against which we benchmark our system. PMID:17299225

  19. Inorganic Nanoparticles for Multimodal Molecular Imaging

    PubMed Central

    Swierczewska, Magdalena; Lee, Seulki; Chen, Xiaoyuan

    2013-01-01

    Multimodal molecular imaging can offer a synergistic improvement of diagnostic ability over a single imaging modality. Recent development of hybrid imaging systems has profoundly impacted the pool of available multimodal imaging probes. In particular, much interest has been focused on biocompatible, inorganic nanoparticle–based multimodal probes. Inorganic nanoparticles offer exceptional advantages to the field of multimodal imaging owing to their unique characteristics, such as nanometer dimensions, tunable imaging properties, and multifunctionality. Nanoparticles mainly based on iron oxide, quantum dots, gold, and silica have been applied to various imaging modalities to characterize and image specific biologic processes on a molecular level. A combination of nanoparticles and other materials such as biomolecules, polymers, and radiometals continue to increase functionality for in vivo multimodal imaging and therapeutic agents. In this review, we discuss the unique concepts, characteristics, and applications of the various multimodal imaging probes based on inorganic nanoparticles. PMID:21303611

  20. Decoherence of multimode thermal squeezed coherent states

    SciTech Connect

    Yeh, L.

    1992-08-14

    It is well known that any multimode positive definite quadratic Hamiltonian can be transformed into a hamiltonian of uncoupled harmonic oscillators. Based on this theorem, the multimode thermal squeezed coherent states are constructed in terms of density operators. Decoherence of multimode thermal squeezed coherent states in investigated via the characteristic function and it is shown that the decohered (reduced) states are still thermal squeezed coherent states in general.

  1. Decoherence of multimode thermal squeezed coherent states

    NASA Technical Reports Server (NTRS)

    Yeh, Leehwa

    1993-01-01

    It is well known that any multimode positive definite quadratic Hamiltonian can be transformed into a Hamiltonian of uncoupled harmonic oscillators. Based on this theorem, the multimode thermal squeezed coherent states are constructed in terms of density operators. Decoherence of multimode thermal squeezed coherent states is investigated via the characteristic function and it is shown that the decohered (reduced) states are still thermal squeezed coherent states in general.

  2. Multi-Mode Broadband Patch Antenna

    NASA Technical Reports Server (NTRS)

    Romanofsky, Robert R. (Inventor)

    2001-01-01

    A multi-mode broad band patch antenna is provided that allows for the same aperture to be used at independent frequencies such as reception at 19 GHz and transmission at 29 GHz. Furthermore, the multi-mode broadband patch antenna provides a ferroelectric film that allows for tuning capability of the multi-mode broadband patch antenna over a relatively large tuning range. The alternative use of a semiconductor substrate permits reduced control voltages since the semiconductor functions as a counter electrode.

  3. Advances in multimodality molecular imaging

    PubMed Central

    Zaidi, Habib; Prasad, Rameshwar

    2009-01-01

    Multimodality molecular imaging using high resolution positron emission tomography (PET) combined with other modalities is now playing a pivotal role in basic and clinical research. The introduction of combined PET/CT systems in clinical setting has revolutionized the practice of diagnostic imaging. The complementarity between the intrinsically aligned anatomic (CT) and functional or metabolic (PET) information provided in a “one-stop shop” and the possibility to use CT images for attenuation correction of the PET data has been the driving force behind the success of this technology. On the other hand, combining PET with Magnetic Resonance Imaging (MRI) in a single gantry is technically more challenging owing to the strong magnetic fields. Nevertheless, significant progress has been made resulting in the design of few preclinical PET systems and one human prototype dedicated for simultaneous PET/MR brain imaging. This paper discusses recent advances in PET instrumentation and the advantages and challenges of multimodality imaging systems. Future opportunities and the challenges facing the adoption of multimodality imaging instrumentation will also be addressed. PMID:20098557

  4. Radioactive Nanomaterials for Multimodality Imaging

    PubMed Central

    Chen, Daiqin; Dougherty, Casey A.; Yang, Dongzhi; Wu, Hongwei; Hong, Hao

    2016-01-01

    Nuclear imaging techniques, including primarily positron emission tomography (PET) and single-photon emission computed tomography (SPECT), can provide quantitative information for a biological event in vivo with ultra-high sensitivity, however, the comparatively low spatial resolution is their major limitation in clinical application. By convergence of nuclear imaging with other imaging modalities like computed tomography (CT), magnetic resonance imaging (MRI) and optical imaging, the hybrid imaging platforms can overcome the limitations from each individual imaging technique. Possessing versatile chemical linking ability and good cargo-loading capacity, radioactive nanomaterials can serve as ideal imaging contrast agents. In this review, we provide a brief overview about current state-of-the-art applications of radioactive nanomaterials in the circumstances of multimodality imaging. We present strategies for incorporation of radioisotope(s) into nanomaterials along with applications of radioactive nanomaterials in multimodal imaging. Advantages and limitations of radioactive nanomaterials for multimodal imaging applications are discussed. Finally, a future perspective of possible radioactive nanomaterial utilization is presented for improving diagnosis and patient management in a variety of diseases. PMID:27227167

  5. Design and assessment of a potent sodium channel blocking derivative of mexiletine for minimizing experimental neuropathic pain in several rat models.

    PubMed

    Weston, Robert M; Subasinghe, Kamani R; Staikopoulos, Vasiliki; Jarrott, Bevyn

    2009-10-01

    Physical or chemical damage to peripheral nerves can result in neuropathic pain which is not easily alleviated by conventional analgesic drugs. Substantial evidence has demonstrated that voltage-gated Na+ channels in the membrane of damaged nerves play a key role in the establishment and maintenance of pathological neuronal excitability not only of these peripheral nerves but also in the second- and third-order neurons in the pain pathway to the cerebral cortex. Na+ channel blocking drugs have been used in treating neuropathic pain with limited success mainly because of a preponderance of side-effects. We have developed an analogue of mexiletine which is approximately 80 times more potent than mexiletine in competing with the radioligand, 3H-batrachotoxinin for binding to Na+ channels in rat brain membranes and also it is much more lipophilic than mexiletine which should enhance its uptake into the brain to block the increased expression of Na+ channels on second- and third-order neurons of the pain pathway. This analogue, HFI-1, has been tested in three different rat models of neuropathic pain (formalin paw model, ligated spinal nerve model and contusive spinal cord injury model) and found to be more effective in reducing pain behaviours than mexiletine. PMID:19504185

  6. Imaging Pain.

    PubMed

    Martucci, Katherine T; Mackey, Sean C

    2016-06-01

    The challenges and understanding of acute and chronic pain have been illuminated through the advancement of central neuroimaging. Through neuroimaging research, new technology and findings have allowed us to identify and understand the neural mechanisms contributing to chronic pain. Several regions of the brain are known to be of particular importance for the maintenance and amplification of chronic pain, and this knowledge provides novel targets for future research and treatment. This article reviews neuroimaging for the study of chronic pain, and in particular, the rapidly advancing and popular research tools of structural and functional MRI. PMID:27208709

  7. Detailed investigation of self-imaging in large-core multimode optical fibers for application in fiber lasers and amplifiers.

    PubMed

    Zhu, X; Schülzgen, A; Li, H; Li, L; Han, L; Moloney, J V; Peyghambarian, N

    2008-10-13

    Properties of the self-imaging effect based on multimode interference (MMI) in large-core passive optical fibers are investigated and analyzed in detail, with the purpose of using multimode active fibers for high power single-transverse-mode emission. Although perfect self-imaging of the input field from a standard single-mode fiber (SMF-28) in a multimode fiber becomes practically impossible as its core diameter is larger than 50 microm, a quasi-reproduction of the input field occurs when the phase difference between the excited modes and the peak mode inside the multimode fiber is very small. Our simulation and experimental results indicate that, if the length of the multimode fiber segment can be controlled accurately, reproduction of the input field with a self-imaging quality factor larger than 0.9 can be obtained. In this case, a low-loss hybrid fiber cavity composed of a SMF-28 segment and a very-large-core active multimode fiber segment can be built. It is also found that for the hybrid fiber cavity, increasing the mode-field diameter of the single-mode fiber improves both the self-imaging quality and the tolerance on the required length accuracy of the multimode fiber segment. Moreover, in this paper key parameters for the design of MMI-based fiber devices are defined and their corresponding values are provided for multimode fibers with core diameters of 50 microm and 105 microm.

  8. A secure and user-friendly multimodal biometric system

    NASA Astrophysics Data System (ADS)

    Takahashi, Kenta; Mimura, Masahiro; Isobe, Yoshiaki; Seto, Yoichi

    2004-08-01

    Biometric verification has attracted attention recently because it is more secure than knowledge- or token-based verification techniques. Multi-modal biometric verification can provide even greater accuracy by combining several forms of biometrics. However, there are problems with the availability, usability and acceptability of the technique. In this paper, we take a new approach in proposing a multi-modal biometric system that enables users to select which biometrics they prefer to be matched at the time of verification. This system also reduces the number of inputs required by adopting a sequential test based on statistical methods. In addition, the accuracy of the system can be controlled according to the security level required. We demonstrated the effectiveness of the proposed system experimentally.

  9. Reconfigurable optical interconnection network for multimode optical fiber sensor arrays

    NASA Technical Reports Server (NTRS)

    Chen, R. T.; Robinson, D.; Lu, H.; Wang, M. R.; Jannson, T.; Baumbick, R.

    1992-01-01

    A single-source, single-detector architecture has been developed to implement a reconfigurable optical interconnection network multimode optical fiber sensor arrays. The network was realized by integrating LiNbO3 electrooptic (EO) gratings working at the Raman Na regime and a massive fan-out waveguide hologram (WH) working at the Bragg regime onto a multimode glass waveguide. The glass waveguide utilized the whole substrate as a guiding medium. A 1-to-59 massive waveguide fan-out was demonstrated using a WH operating at 514 nm. Measured diffraction efficiency of 59 percent was experimentally confirmed. Reconfigurability of the interconnection was carried out by generating an EO grating through an externally applied electric field. Unlike conventional single-mode integrated optical devices, the guided mode demonstrated has an azimuthal symmetry in mode profile which is the same as that of a fiber mode.

  10. A multi-modal treatment approach for the shoulder: A 4 patient case series

    PubMed Central

    Pribicevic, Mario; Pollard, Henry

    2005-01-01

    Background This paper describes the clinical management of four cases of shoulder impingement syndrome using a conservative multimodal treatment approach. Clinical Features Four patients presented to a chiropractic clinic with chronic shoulder pain, tenderness in the shoulder region and a limited range of motion with pain and catching. After physical and orthopaedic examination a clinical diagnosis of shoulder impingement syndrome was reached. The four patients were admitted to a multi-modal treatment protocol including soft tissue therapy (ischaemic pressure and cross-friction massage), 7 minutes of phonophoresis (driving of medication into tissue with ultrasound) with 1% cortisone cream, diversified spinal and peripheral joint manipulation and rotator cuff and shoulder girdle muscle exercises. The outcome measures for the study were subjective/objective visual analogue pain scales (VAS), range of motion (goniometer) and return to normal daily, work and sporting activities. All four subjects at the end of the treatment protocol were symptom free with all outcome measures being normal. At 1 month follow up all patients continued to be symptom free with full range of motion and complete return to normal daily activities. Conclusion This case series demonstrates the potential benefit of a multimodal chiropractic protocol in resolving symptoms associated with a suspected clinical diagnosis of shoulder impingement syndrome. PMID:16168053

  11. Recent advances in the treatment of pain

    PubMed Central

    2010-01-01

    Cancer pain and chronic non-malignant pain can be difficult to manage and may not respond satisfactorily to standard analgesics. Sequential empiric analgesic trials are usually done to manage individual patients. Experimental human pain models have helped to clarify mechanisms of opioid and adjuvant analgesic actions. Combinations of opioids and adjuvant analgesics better relieve pain than either opioids or adjuvant analgesics alone, as demonstrated in randomized controlled trials. The analgesic activity of antidepressants is largely dependent upon norepinephrine reuptake and activation of alpha 2 adrenergic receptors. Corticosteroids reduce postoperative orthopedic incident pain, which may allow patients to ambulate earlier and with less pain. Spinal corticosteroids reduce lower hemibody pain. Gabapentinoids as single high doses reduce postoperative pain and certain acute pain syndromes. Individuals who experience flares of pain while on spinal opioids benefit from intrathecal boluses of levobupivicaine or sublingual ketamine. Interventional approaches to pain management are often necessary due to the limitations of systemic analgesics. Electronics stimulators (peripheral, spinal and motor cortex) improve difficult to manage chronic pain syndromes. Pulsed radiofrequency reduces pain without tissue damage, which could be an advantage over chemical or radiofrequency neurotomy. Botulinum toxin A reduces focal neuropathic pain that is durable. Interventional related successes in relieving pain are operator dependent. Most reported benefits of systemic and regional analgesics and interventional approaches to pain relief are not based on randomized trials and are subject to selection bias, sampling error, and placebo responses, which may over-inflate reported benefits. Randomized controlled trials are needed to confirm reported benefits. PMID:21173850

  12. Multimodal approach for the management of Hunan hand syndrome: a case report.

    PubMed

    Saxena, Ashok Kumar; Mandhyan, Rajani

    2013-03-01

    Hunan hand syndrome, a form of painful contact dermatitis, is a rare case finding. It is usually seen in people with continuous and prolonged exposure to chili peppers. The main ingredient in chili peppers is capsaicin that leads to the clinical condition, Hunan hand syndrome. This is paradoxical to the use of capsaicin as local application for relief of pain in various clinical situations, such as diabetic neuropathy and postherpetic neuralgia. We report a case of Hunan hand syndrome, managed successfully by using a multimodal approach comprised of a continuous stellate ganglion block, gabapentin, local ice water, and fluocinonide application.

  13. Multimodal approach for the management of Hunan hand syndrome: a case report.

    PubMed

    Saxena, Ashok Kumar; Mandhyan, Rajani

    2013-03-01

    Hunan hand syndrome, a form of painful contact dermatitis, is a rare case finding. It is usually seen in people with continuous and prolonged exposure to chili peppers. The main ingredient in chili peppers is capsaicin that leads to the clinical condition, Hunan hand syndrome. This is paradoxical to the use of capsaicin as local application for relief of pain in various clinical situations, such as diabetic neuropathy and postherpetic neuralgia. We report a case of Hunan hand syndrome, managed successfully by using a multimodal approach comprised of a continuous stellate ganglion block, gabapentin, local ice water, and fluocinonide application. PMID:22681338

  14. Cryoanalgesia for pain after herniorrhaphy.

    PubMed

    Khiroya, R C; Davenport, H T; Jones, J G

    1986-01-01

    The effect of freezing the ilioinguinal nerve on postoperative pain relief was examined in a double blind study in 36 patients undergoing herniorrhaphy, randomly allocated into two groups. Patients in the experimental group had their ilioinguinal nerves frozen during surgery and were compared with the patients in the control group who did not have cryoanalgesia. Pain relief was assessed over a 48-hour period in three ways, namely the linear analogue pain scale, peak expiratory flow rates and the amount of analgesic drugs required by patients in the two groups. We conclude that cryoanalgesia of the ilioinguinal nerve alone does not produce significant early post herniorrhaphy pain relief. PMID:3511766

  15. Operant learning theory in pain and chronic pain rehabilitation.

    PubMed

    Gatzounis, Rena; Schrooten, Martien G S; Crombez, Geert; Vlaeyen, Johan W S

    2012-04-01

    The application of operant learning theory on chronic pain by Fordyce has had a huge impact on chronic pain research and management. The operant model focuses on pain behaviors as a major component of the pain problem, and postulates that they are subject to environmental contingencies. The role of operant learning in pain behaviors generally has been supported by experimental studies, which are reviewed in the present article. Subsequently, the rationale, goals, and methods of operant behavioral treatment of chronic pain are outlined. Special attention is paid to three therapeutic techniques (graded activity, activity pacing, and time-contingent medication management), which are discussed in detail with regard to their operationalization, effectiveness, and (possible) mechanisms of action. Criticisms of the operant model are presented, as are suggestions for the optimization of (operant) behavioral treatment efficacy.

  16. Expanding hypnotic pain management to the affective dimension of pain.

    PubMed

    Feldman, Jeffrey B

    2009-01-01

    Experimental (Price & Barber, 1987) and neuroimaging studies (Rainville, Carrier, Hofbauer, Bushnell, & Duncan, 1999), suggest that it is the affective dimension of pain as processed in the anterior cingulate cortex (ACC) that is most associated with suffering and autonomic arousal. Conversely, pain related emotions (Rainville, Bao, & Chretien, 2005) and expectations (Koyama, McHaffie, Laurenti, & Coghill, 2005) modulate pain perception and associated pain affect. This paper presents both the scientific background and the general clinical steps involved in a practical hypnotic approach that uses emotion specific wording and the elicitation of prior positive experience to intervene at both the affective and sensory dimensions of pain. Such an approach enables patients to therapeutically use hypnosis to reduce their subjective distress even if they are not able to greatly reduce the sensation of pain. The utilization of positive state dependent learning (Rossi, 1986), following the advice of Milton Erickson to "discover their patterns of happiness" (Parsons-Fein, 2005) is emphasized.

  17. Operant learning theory in pain and chronic pain rehabilitation.

    PubMed

    Gatzounis, Rena; Schrooten, Martien G S; Crombez, Geert; Vlaeyen, Johan W S

    2012-04-01

    The application of operant learning theory on chronic pain by Fordyce has had a huge impact on chronic pain research and management. The operant model focuses on pain behaviors as a major component of the pain problem, and postulates that they are subject to environmental contingencies. The role of operant learning in pain behaviors generally has been supported by experimental studies, which are reviewed in the present article. Subsequently, the rationale, goals, and methods of operant behavioral treatment of chronic pain are outlined. Special attention is paid to three therapeutic techniques (graded activity, activity pacing, and time-contingent medication management), which are discussed in detail with regard to their operationalization, effectiveness, and (possible) mechanisms of action. Criticisms of the operant model are presented, as are suggestions for the optimization of (operant) behavioral treatment efficacy. PMID:22261987

  18. Neck Pain

    MedlinePlus

    ... get better. No 7. Did you have a whiplash-type injury in the past, or do you have pain and/or stiffness every day in your neck, hands, knees, hips or other joints? Yes Your pain may be from DEGENERATIVE CERVICAL ARTHRITIS, a disorder that affects the bones and ...

  19. Standardized Aqueous Tribulus terristris (nerunjil) extract attenuates hyperalgesia in experimentally induced diabetic neuropathic pain model: role of oxidative stress and inflammatory mediators.

    PubMed

    Ranjithkumar, Ravichandran; Prathab Balaji, S; Balaji, Bhaskar; Ramesh, R V; Ramanathan, Muthiah

    2013-11-01

    The present study aimed to evaluate standardized aqueous Tribulus terristris (nerunjil) extract on the pain threshold response in streptozotocin (STZ)-induced diabetic neuropathic pain model in rats. After a single injection of STZ (40 mg/kg; i.p.), Wistar male rats were tested by the thermal and chemical-induced pain models. Diabetic rats exhibited significant hyperalgesia, and these rats were left untreated for the first four weeks. Thereafter, treatment was initiated and continued up to week-8. All the rats except the vehicle-treated group received insulin 5 IU/kg/day to maintain plasma glucose levels. Treatment with nerunjil (100 and 300 mg/kg; p.o.) for 4 weeks significantly attenuated the nociception in behavioural models. Nerunjil also inhibited the tumour necrosis factor-α and interleukin-1 beta levels. The effect of nerunjil (300 mg/kg) is comparable to the standard drug Pregabalin (100 mg/kg). Nerunjil increased the superoxide dismutase, catalase, glutathione peroxidase, reduced glutathione, and decreased the lipid peroxide levels in dose-dependent manner. Insulin alone-treated rats failed to attenuate hyperalgesic response. In comparison to insulin alone-treated rats, nerunjil exhibited significant increase in the pain threshold response. It could be concluded that in controlled diabetic states, nerunjil attenuated the neuropathic pain through modulation of oxidative stress and inflammatory cytokine release.

  20. Gender role expectations of pain is associated with pain tolerance limit but not with pain threshold.

    PubMed

    Defrin, Ruth; Shramm, Libby; Eli, Ilana

    2009-09-01

    Gender role expectations of pain (GREP) was suggested to predict sex differences in pain perception. Our aim was to explore sex differences in GREP and investigate its relationship with heat-pain threshold (HPT) and heat-pain tolerance limit (HPTL). University students (115 males, 134 females) filled the GREP questionnaire. HPT and HPTL were measured in a sample of 72 students. Additionally, GREP values of the present sample were compared with those of the original, American sample to explore possible cultural effects. Both males and females perceive themselves (and their own sex in general) to be less sensitive to pain and less willing to report of pain than the opposite sex. Males perceived themselves and other men, to endure pain relatively similar to women whereas females perceived themselves and other women as less endurable to pain than men. HPT was similar for the two sexes but males had higher HPTL than females. Within each sex, HPTL correlated mainly with self's perception of pain sensitivity. The American and Israeli samples differed in that Israeli males and females presented stronger stereotypical views towards same and opposite sexes. Both males and females held stereotypical "macho" attitude towards themselves with regard to pain sensitivity and willingness to report of pain however only females held stereotypical, "macho" attitude towards themselves with regard to pain endurance. The sex differences in GREP and in HPTL and the correlations between GREP items and experimental thresholds suggest that the relationship between GREP and experimental pain is complex and sex-specific. It also appears that GREP is affected by culture.

  1. Road map for pain management in pancreatic cancer: A review.

    PubMed

    Lahoud, Marie José; Kourie, Hampig Raphael; Antoun, Joelle; El Osta, Lana; Ghosn, Marwan

    2016-08-15

    Beside its poor prognosis and its late diagnosis, pancreatic cancer remains one of the most painful malignancies. Optimal management of pain in this cancer represents a real challenge for the oncologist whose objective is to ensure a better quality of life to his patients. We aimed in this paper to review all the treatment modalities incriminated in the management of pain in pancreatic cancer going from painkillers, chemotherapy, radiation therapy and interventional techniques to agents under investigation and alternative medicine. Although specific guidelines and recommendations for pain management in pancreatic cancer are still absent, we present all the possible pain treatments, with a progression from medical multimodal treatment to radiotherapy and chemotherapy then interventional techniques in case of resistance. In addition, alternative methods such as acupuncture and hypnosis can be added at any stage and seems to contribute to pain relief. PMID:27574552

  2. Road map for pain management in pancreatic cancer: A review

    PubMed Central

    Lahoud, Marie José; Kourie, Hampig Raphael; Antoun, Joelle; El Osta, Lana; Ghosn, Marwan

    2016-01-01

    Beside its poor prognosis and its late diagnosis, pancreatic cancer remains one of the most painful malignancies. Optimal management of pain in this cancer represents a real challenge for the oncologist whose objective is to ensure a better quality of life to his patients. We aimed in this paper to review all the treatment modalities incriminated in the management of pain in pancreatic cancer going from painkillers, chemotherapy, radiation therapy and interventional techniques to agents under investigation and alternative medicine. Although specific guidelines and recommendations for pain management in pancreatic cancer are still absent, we present all the possible pain treatments, with a progression from medical multimodal treatment to radiotherapy and chemotherapy then interventional techniques in case of resistance. In addition, alternative methods such as acupuncture and hypnosis can be added at any stage and seems to contribute to pain relief. PMID:27574552

  3. Effect of establishing pain committee on the pain assessment skills of paediatric nurses.

    PubMed

    Farahani, Pouran Varvani; Alhani, Fatemeh; Mohammadi, Eisa

    2014-10-01

    Successful pain management relies on pain assessment. The purpose of this study is to investigate the effect of establishing pain committee on pain assessment skills of paediatric nurses. We used a quasi-experimental design. The study was conducted in surgery, emergency and orthopaedic wards of two teaching hospitals selected through simple random sampling. The intervention consisted of establishing a pain committee, the steps of which included organizing (3 months), holding workshop (five sessions) and clinical training (1 week). We found that the scores in the intervention group were significantly higher than those in the control group. Therefore, establishing pain committee in the management level of nursing improves nurses' pain assessment skills.

  4. Spinal pain.

    PubMed

    Izzo, R; Popolizio, T; D'Aprile, P; Muto, M

    2015-05-01

    The spinal pain, and expecially the low back pain (LBP), represents the second cause for a medical consultation in primary care setting and a leading cause of disability worldwide [1]. LBP is more often idiopathic. It has as most frequent cause the internal disc disruption (IDD) and is referred to as discogenic pain. IDD refers to annular fissures, disc collapse and mechanical failure, with no significant modification of external disc shape, with or without endplates changes. IDD is described as a separate clinical entity in respect to disc herniation, segmental instability and degenerative disc desease (DDD). The radicular pain has as most frequent causes a disc herniation and a canal stenosis. Both discogenic and radicular pain also have either a mechanical and an inflammatory genesis. For to be richly innervated, facet joints can be a direct source of pain, while for their degenerative changes cause compression of nerve roots in lateral recesses and in the neural foramina. Degenerative instability is a common and often misdiagnosed cause of axial and radicular pain, being also a frequent indication for surgery. Acute pain tends to extinguish along with its cause, but the setting of complex processes of peripheral and central sensitization may influence its evolution in chronic pain, much more difficult to treat. The clinical assessment of pain source can be a challenge because of the complex anatomy and function of the spine; the advanced imaging methods are often not sufficient for a definitive diagnosis because similar findings could be present in either asymptomatic and symptomatic subjects: a clinical correlation is always mandatory and the therapy cannot rely uniquely upon any imaging abnormalities. Purpose of this review is to address the current concepts on the pathophysiology of discogenic, radicular, facet and dysfunctional pain, focusing on the role of the imaging in the diagnostic setting, to potentially address a correct approach also to minimally

  5. Multimodal Narrative Inquiry: Six Teacher Candidates Respond

    ERIC Educational Resources Information Center

    Morawski, Cynthia M.; Rottmann, Jennifer

    2016-01-01

    In this paper we present findings of a study on the implementation of a multimodal teacher narrative inquiry component, theoretically grounded by Rosenblatt's theory of transaction analysis, methodologically supported by action research and practically enacted by narrative inquiry and multimodal learning. In particular, the component offered…

  6. Radiolabeled Nanoparticles for Multimodality Tumor Imaging

    PubMed Central

    Xing, Yan; Zhao, Jinhua; Conti, Peter S.; Chen, Kai

    2014-01-01

    Each imaging modality has its own unique strengths. Multimodality imaging, taking advantages of strengths from two or more imaging modalities, can provide overall structural, functional, and molecular information, offering the prospect of improved diagnostic and therapeutic monitoring abilities. The devices of molecular imaging with multimodality and multifunction are of great value for cancer diagnosis and treatment, and greatly accelerate the development of radionuclide-based multimodal molecular imaging. Radiolabeled nanoparticles bearing intrinsic properties have gained great interest in multimodality tumor imaging over the past decade. Significant breakthrough has been made toward the development of various radiolabeled nanoparticles, which can be used as novel cancer diagnostic tools in multimodality imaging systems. It is expected that quantitative multimodality imaging with multifunctional radiolabeled nanoparticles will afford accurate and precise assessment of biological signatures in cancer in a real-time manner and thus, pave the path towards personalized cancer medicine. This review addresses advantages and challenges in developing multimodality imaging probes by using different types of nanoparticles, and summarizes the recent advances in the applications of radiolabeled nanoparticles for multimodal imaging of tumor. The key issues involved in the translation of radiolabeled nanoparticles to the clinic are also discussed. PMID:24505237

  7. Evaluating Multimodal Literacies in Student Blogs

    ERIC Educational Resources Information Center

    O'Byrne, Barbara; Murrell, Stacey

    2014-01-01

    This research presents ways in which high school students used the multimodal and interactive affordances of blogs to create, organize, communicate and participate on an educational blog. Their actions demonstrated how plural modes of literacy are infiltrating digital environments and reshaping literacy and learning. Multimodal blogging practices…

  8. Literacy, Media and Multimodality: A Critical Response

    ERIC Educational Resources Information Center

    Bazalgette, Cary; Buckingham, David

    2013-01-01

    In recent years, literacy educators have increasingly recognised the importance of addressing a broader range of texts in the classroom. This article raises some critical concerns about a particular approach to this issue that has been widely promoted in recent years-- the concept of "multimodality". Multimodality theory offers a broadly…

  9. Multimodal Literacies in the Secondary English Classroom

    ERIC Educational Resources Information Center

    Sewell, William C.; Denton, Shawn

    2011-01-01

    To provide insight into the issue of multimodal literacy instruction, the authors explore presentation techniques and instructional activities employed in their secondary language arts classes. They collaborate on assignments that focus students on "anchored media instruction" and engage them in producing multimodal, technology-infused projects,…

  10. Multimodality, Literacy and Texts: Developing a Discourse

    ERIC Educational Resources Information Center

    Bearne, Eve

    2009-01-01

    This article argues for the development of a framework through which to describe children's multimodal texts. Such a shared discourse should be capable of including different modes and media and the ways in which children integrate and combine them for their own meaning-making purposes. It should also acknowledge that multimodal texts are not…

  11. Filter. Remix. Make.: Cultivating Adaptability through Multimodality

    ERIC Educational Resources Information Center

    Dusenberry, Lisa; Hutter, Liz; Robinson, Joy

    2015-01-01

    This article establishes traits of adaptable communicators in the 21st century, explains why adaptability should be a goal of technical communication educators, and shows how multimodal pedagogy supports adaptability. Three examples of scalable, multimodal assignments (infographics, research interviews, and software demonstrations) that evidence…

  12. Review of perioperative pain management of opioid-dependent patients.

    PubMed

    Vadivelu, Nalini; Mitra, Sukanya; Kai, Alice M; Kodumudi, Gopal; Gritsenko, Karina

    2016-01-01

    Opioid dependence can occur due to prescription opioid use, recreational opioid use, or as a result of opioid use for the treatment of drug addiction. Pain control in these patients is truly a challenge. It is important to understand the patient's condition such as the phenomenon of drug dependence, drug addiction, and pseudoaddiction to provide effective analgesia. This may be accomplished using appropriate multimodal therapies and by treatment of coexisting diseases such as anxiety. The goal is to provide effective analgesia, prevent cognitive and emotional problems, and produce a positive postoperative rehabilitation process. Multimodal options include pharmacological and nonpharmacological approaches, psychological support, and interventional pain procedures, all focused toward providing optimal pain control while preventing undertreatment, withdrawal symptoms, and other complications. PMID:27575830

  13. Managing Chronic Pain in Special Populations with Emphasis on Pediatric, Geriatric, and Drug Abuser Populations.

    PubMed

    Baumbauer, Kyle M; Young, Erin E; Starkweather, Angela R; Guite, Jessica W; Russell, Beth S; Manworren, Renee C B

    2016-01-01

    In the adult population chronic pain can lead to loss of productivity and earning potential, and decreased quality of life. There are distinct groups with increased vulnerability for the emergence of chronic pain. These groups may be defined by developmental status and/or life circumstances. Within the pediatric, geriatric, and drug abuser populations, chronic pain represents a significant health issue. This article focuses on known anatomic, physiologic, and genetic mechanisms underlying chronic pain in these populations, and highlights the need for a multimodal approach from multiple health care professionals for management of chronic pain in those with the most risk.

  14. Managing Chronic Pain in Special Populations with Emphasis on Pediatric, Geriatric, and Drug Abuser Populations.

    PubMed

    Baumbauer, Kyle M; Young, Erin E; Starkweather, Angela R; Guite, Jessica W; Russell, Beth S; Manworren, Renee C B

    2016-01-01

    In the adult population chronic pain can lead to loss of productivity and earning potential, and decreased quality of life. There are distinct groups with increased vulnerability for the emergence of chronic pain. These groups may be defined by developmental status and/or life circumstances. Within the pediatric, geriatric, and drug abuser populations, chronic pain represents a significant health issue. This article focuses on known anatomic, physiologic, and genetic mechanisms underlying chronic pain in these populations, and highlights the need for a multimodal approach from multiple health care professionals for management of chronic pain in those with the most risk. PMID:26614727

  15. What a Pain! Kids and Growing Pains

    MedlinePlus

    ... Here's Help White House Lunch Recipes What a Pain! Kids and Growing Pains KidsHealth > For Kids > What a Pain! Kids and ... something doctors call growing pains . What Are Growing Pains? Growing pains aren't a disease. You probably ...

  16. Chronic pain syndromes, mechanisms, and current treatments.

    PubMed

    Sirianni, Justin; Ibrahim, Mohab; Patwardhan, Amol

    2015-01-01

    Although acute pain is a physiological response warning the human body of possible harm, chronic pain can be a pathological state associated with various diseases or a disease in itself. In the United States alone, around one-third of the population has experienced a chronic pain condition and annual cost to the society is in the range of 500-600 billion dollars.(1) It should be noted that if at all this is a very modest estimate, it surpasses the costs associated with cancer, heart disease, and diabetes combined.(1) Unfortunately, despite these humongous costs, the treatment of chronic pain is inadequate.(1) Chronic pain affects individuals in a variety of forms, and below we highlight some of the most common chronic pain conditions seen in a pain clinic. Most of these disorders are difficult to treat and typically require multimodal therapy including pharmacotherapy, behavioral modification, and targeted interventions. We have summarized the scope of each disorder, clinical features, proposed mechanisms, and current therapies for them (Table 1).

  17. Optimizing and Interpreting Insular Functional Connectivity Maps Obtained During Acute Experimental Pain: The Effects of Global Signal and Task Paradigm Regression.

    PubMed

    Ibinson, James W; Vogt, Keith M; Taylor, Kevin B; Dua, Shiv B; Becker, Christopher J; Loggia, Marco; Wasan, Ajay D

    2015-12-01

    The insula is uniquely located between the temporal and parietal cortices, making it anatomically well-positioned to act as an integrating center between the sensory and affective domains for the processing of painful stimulation. This can be studied through resting-state functional connectivity (fcMRI) imaging; however, the lack of a clear methodology for the analysis of fcMRI complicates the interpretation of these data during acute pain. Detected connectivity changes may reflect actual alterations in low-frequency synchronous neuronal activity related to pain, may be due to changes in global cerebral blood flow or the superimposed task-induced neuronal activity. The primary goal of this study was to investigate the effects of global signal regression (GSR) and task paradigm regression (TPR) on the changes in functional connectivity of the left (contralateral) insula in healthy subjects at rest and during acute painful electric nerve stimulation of the right hand. The use of GSR reduced the size and statistical significance of connectivity clusters and created negative correlation coefficients for some connectivity clusters. TPR with cyclic stimulation gave task versus rest connectivity differences similar to those with a constant task, suggesting that analysis which includes TPR is more accurately reflective of low-frequency neuronal activity. Both GSR and TPR have been inconsistently applied to fcMRI analysis. Based on these results, investigators need to consider the impact GSR and TPR have on connectivity during task performance when attempting to synthesize the literature.

  18. Quercetin for chronic prostatitis/chronic pelvic pain syndrome.

    PubMed

    Shoskes, Daniel A; Nickel, J Curtis

    2011-08-01

    Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a common condition with a heterogeneous origin that responds best to multimodal therapy. The bioflavonoid quercetin has antioxidant and antiinflammatory effects that have proven useful for treating this condition. Using the clinical phenotype system UPOINT, quercetin can be helpful for those with organ-specific complaints (bladder or prostate) and pelvic floor spasm. This article discusses the current understanding of CP/CPPS and how treatment with quercetin can be used alone or as part of multimodal therapy.

  19. Prevent Back Pain

    MedlinePlus

    ... Back Pain Print This Topic En español Prevent Back Pain Browse Sections The Basics Overview Am I at ... Health: Back Pain . There are different types of back pain. Back pain can be acute or chronic. It ...

  20. Chronic pain - resources

    MedlinePlus

    Pain - resources; Resources - chronic pain ... The following organizations are good resources for information on chronic pain: American Chronic Pain Association -- www.theacpa.org National Fibromyalgia and Chronic Pain Association -- www.fmcpaware.org ...

  1. Manifold regularized multitask feature learning for multimodality disease classification.

    PubMed

    Jie, Biao; Zhang, Daoqiang; Cheng, Bo; Shen, Dinggang

    2015-02-01

    Multimodality based methods have shown great advantages in classification of Alzheimer's disease (AD) and its prodromal stage, that is, mild cognitive impairment (MCI). Recently, multitask feature selection methods are typically used for joint selection of common features across multiple modalities. However, one disadvantage of existing multimodality based methods is that they ignore the useful data distribution information in each modality, which is essential for subsequent classification. Accordingly, in this paper we propose a manifold regularized multitask feature learning method to preserve both the intrinsic relatedness among multiple modalities of data and the data distribution information in each modality. Specifically, we denote the feature learning on each modality as a single task, and use group-sparsity regularizer to capture the intrinsic relatedness among multiple tasks (i.e., modalities) and jointly select the common features from multiple tasks. Furthermore, we introduce a new manifold-based Laplacian regularizer to preserve the data distribution information from each task. Finally, we use the multikernel support vector machine method to fuse multimodality data for eventual classification. Conversely, we also extend our method to the semisupervised setting, where only partial data are labeled. We evaluate our method using the baseline magnetic resonance imaging (MRI), fluorodeoxyglucose positron emission tomography (FDG-PET), and cerebrospinal fluid (CSF) data of subjects from AD neuroimaging initiative database. The experimental results demonstrate that our proposed method can not only achieve improved classification performance, but also help to discover the disease-related brain regions useful for disease diagnosis. PMID:25277605

  2. Sparse recovery of the multimodal and dispersive characteristics of Lamb waves.

    PubMed

    Harley, Joel B; Moura, José M F

    2013-05-01

    Guided waves in plates, known as Lamb waves, are characterized by complex, multimodal, and frequency dispersive wave propagation, which distort signals and make their analysis difficult. Estimating these multimodal and dispersive characteristics from experimental data becomes a difficult, underdetermined inverse problem. To accurately and robustly recover these multimodal and dispersive properties, this paper presents a methodology referred to as sparse wavenumber analysis based on sparse recovery methods. By utilizing a general model for Lamb waves, waves propagating in a plate structure, and robust l1 optimization strategies, sparse wavenumber analysis accurately recovers the Lamb wave's frequency-wavenumber representation with a limited number of surface mounted transducers. This is demonstrated with both simulated and experimental data in the presence of multipath reflections. With accurate frequency-wavenumber representations, sparse wavenumber synthesis is then used to accurately remove multipath interference in each measurement and predict the responses between arbitrary points on a plate.

  3. Orofacial Pain

    MedlinePlus

    ... time. Signs that may indicate a headache of dental origin include: ; Pain behind the eyes Sore jaw muscles or "tired" ... t Sleep? Check Your Bite What Causes a Toothache? Your Posture May Be the Cause of Jaw ...

  4. Abdominal Pain

    MedlinePlus

    ... can help the overall situation for the child. Teaching kids self-hypnosis [8] or guided imagery [8a] ... related topics? Functional Abdominal Pain (English, French or Spanish)—from The North American Society for Pediatric Gastroenterology, ...

  5. Testicle pain

    MedlinePlus

    ... be caused by a hernia or kidney stone. Testicular cancer is almost always painless. But any testicle lump ... Read More Abdominal pain Scrotum Testes Testicle lump Testicular cancer Testicular torsion Update Date 8/31/2015 Updated ...

  6. Pain Control

    MedlinePlus

    ... have tried to find relief from cancer pain. ■■ Physical Therapy. Exercises or methods used to help restore strength, ... that you see a licensed expert when trying physical therapy, massage, hypnosis, or acupuncture. 25 To learn more ...

  7. Neck pain

    MedlinePlus

    A common cause of neck pain is muscle strain or tension. Most often, everyday activities are to blame. Such activities include: Bending over a desk for hours Having poor posture while watching TV or ...

  8. Face pain

    MedlinePlus

    ... gets worse when you bend forward) Tic douloureux Temporomandibular joint dysfunction syndrome Sometimes the reason for the face pain ... is persistent, unexplained, or accompanied by other unexplained symptoms. Call your primary provider. What to Expect at ...

  9. Multimodal signature modeling of humans

    NASA Astrophysics Data System (ADS)

    Cathcart, J. Michael; Kocher, Brian; Prussing, Keith; Lane, Sarah; Thomas, Alan

    2010-04-01

    Georgia Tech been investigating method for the detection of covert personnel in traditionally difficult environments (e.g., urban, caves). This program focuses on a detailed phenomenological analysis of human physiology and signatures with the subsequent identification and characterization of potential observables. Both aspects are needed to support the development of personnel detection and tracking algorithms. The difficult nature of these personnel-related problems dictates a multimodal sensing approach. Human signature data of sufficient and accurate quality and quantity do not exist, thus the development of an accurate signature model for a human is needed. This model should also simulate various human activities to allow motion-based observables to be exploited. This paper will describe a multimodal signature modeling approach that incorporates human physiological aspects, thermoregulation, and dynamics into the signature calculation. This approach permits both passive and active signatures to be modeled. The focus of the current effort involved the computation of signatures in urban environments. This paper will discuss the development of a human motion model for use in simulating both electro-optical signatures and radar-based signatures. Video sequences of humans in a simulated urban environment will also be presented; results using these sequences for personnel tracking will be presented.

  10. Untangled modes in multimode waveguides

    NASA Astrophysics Data System (ADS)

    Plöschner, Martin; Tyc, TomáÅ.¡; Čižmár, TomáÅ.¡

    2016-03-01

    Small, fibre-based endoscopes have already improved our ability to image deep within the human body. A novel approach introduced recently utilised disordered light within a standard multimode optical fibre for lensless imaging. Importantly, this approach brought very significant reduction of the instruments footprint to dimensions below 100 μm. The most important limitations of this exciting technology is the lack of bending flexibility - imaging is only possible as long as the fibre remains stationary. The only route to allow flexibility of such endoscopes is in trading-in all the knowledge about the optical system we have, particularly the cylindrical symmetry of refractive index distribution. In perfect straight step-index cylindrical waveguides we can find optical modes that do not change their spatial distribution as they propagate through. In this paper we present a theoretical background that provides description of such modes in more realistic model of real-life step-index multimode fibre taking into account common deviations in distribution of the refractive index from its ideal step-index profile. Separately, we discuss how to include the influence of fibre bending.

  11. Post-Craniotomy Pain Management: Beyond Opioids.

    PubMed

    Dunn, Lauren K; Naik, Bhiken I; Nemergut, Edward C; Durieux, Marcel E

    2016-10-01

    Craniotomy pain may be severe and is often undertreated. Pain management following craniotomy is a balancing act of achieving adequate analgesia but avoiding sedation, respiratory depression, hypercapnia, nausea and vomiting, and hypertension. Opioids are a first-line analgesic therapy; however, concern that opioid-related adverse effects (sedation, respiratory depression) may interfere with neurologic assessment and increase intracranial pressure has limited use of these drugs for intracranial surgery. Non-opioid analgesics avoid these effects and may be useful as part of a multimodal regimen for post-craniotomy pain. Regional scalp blocks, paracetamol, and non-steroidal anti-inflammatory drugs are beneficial in the early post-operative period. Recent studies suggest a role for novel analgesics: dexmedetomidine, gabapentinoids, and ketamine, though additional studies are necessary. PMID:27604271

  12. Neonatal pain.

    PubMed

    Walker, Suellen M

    2014-01-01

    Effective management of procedural and postoperative pain in neonates is required to minimize acute physiological and behavioral distress and may also improve acute and long-term outcomes. Painful stimuli activate nociceptive pathways, from the periphery to the cortex, in neonates and behavioral responses form the basis for validated pain assessment tools. However, there is an increasing awareness of the need to not only reduce acute behavioral responses to pain in neonates, but also to protect the developing nervous system from persistent sensitization of pain pathways and potential damaging effects of altered neural activity on central nervous system development. Analgesic requirements are influenced by age-related changes in both pharmacokinetic and pharmacodynamic response, and increasing data are available to guide safe and effective dosing with opioids and paracetamol. Regional analgesic techniques provide effective perioperative analgesia, but higher complication rates in neonates emphasize the importance of monitoring and choice of the most appropriate drug and dose. There have been significant improvements in the understanding and management of neonatal pain, but additional research evidence will further reduce the need to extrapolate data from older age groups. Translation into improved clinical care will continue to depend on an integrated approach to implementation that encompasses assessment and titration against individual response, education and training, and audit and feedback.

  13. Liposomal bupivacaine versus traditional periarticular injection for pain control after total knee arthroplasty.

    PubMed

    Bagsby, Deren T; Ireland, Phillip H; Meneghini, R Michael

    2014-08-01

    The purpose of this study was to compare a novel liposomal bupivacaine to traditional peri-articular injection (PAI) in a multi-modal pain protocol for total knee arthroplasty (TKA). A retrospective cohort study compared 85 consecutive patients undergoing TKA with a traditional PAI of ropivacaine, epinephrine and morphine to 65 patients with a liposomal bupivacaine PAI. After the initial 24h, inpatient self-reported pain scores were higher in the liposomal bupivacaine group compared to the traditional PAI group (P = 0.04) and a smaller percentage (16.9%) of patients in the liposomal bupivacaine group rated their pain as "mild" compared to the traditional group (47.6%). Liposomal bupivacaine PAI provided inferior pain control compared to the less expensive traditional PAI in a multi-modal pain control program in patients undergoing TKA.

  14. Availability and Utilization of Opioids for Pain Management: Global Issues

    PubMed Central

    Manjiani, Deepak; Paul, D. Baby; Kunnumpurath, Sreekumar; Kaye, Alan David; Vadivelu, Nalini

    2014-01-01

    Background Pain can significantly influence an individual's health status and can have serious negative consequences: poor nutrition, decreased appetite, abnormal sleep patterns, fatigue, and impairment of daily living activities. Pain can cause psychological impairment and decrease healing and recovery from injuries and illness. A hallmark of many chronic conditions, pain affects more patients' lives than diabetes mellitus, heart disease, and cancer combined. However, many chronic sufferers do not have access to effective pain management for a variety of reasons, including limited access, restrictions, and personal and cultural biases. Methods This review summarizes issues of access, distribution, and cultural bias with regard to opioid agents and seeks to clarify the challenges related to opioid delivery. The considerable negative physical and mental consequences of chronic pain are discussed for the general and palliative care population. Results Opioids are an effective treatment for various intractable painful conditions, but problems in global opioid access for safe and rational use in pain management contribute to unnecessary suffering. These problems persist despite increased understanding in recent years of the pathophysiology of pain. Conclusions Comprehensive guidelines for goal-directed and patient-friendly chronic opiate therapy will potentially enhance the outlook for future chronic pain management. The improvement of pain education in undergraduate and postgraduate training will benefit patients and clinicians. The promise of new medications, along with the utilization of multimodal approaches, has the potential to provide effective pain relief to future generations of sufferers. PMID:24940131

  15. Liposome bupivacaine for postsurgical pain in an obese woman with chronic pain undergoing laparoscopic gastrectomy: a case report

    PubMed Central

    2014-01-01

    Introduction To reduce incidence and severity of postsurgical pain and minimize the effect of its clinical and economic correlates, multimodal therapy for surgical patients is recommended. In this report, we discuss the use of liposome bupivacaine, a novel multivesicular formulation of bupivacaine indicated for single-dose infiltration into the surgical site to produce postsurgical analgesia, as part of a multimodal analgesic regimen in a patient with a history of chronic pain scheduled to undergo laparoscopic sleeve gastrectomy. To the best of our knowledge, this is the first published report of liposome bupivacaine in the setting of laparoscopic sleeve gastrectomy. Case presentation A 35-year-old white woman with morbid obesity was admitted for laparoscopic sleeve gastrectomy to lose weight prior to hip replacement surgery. Because of a complicated medical history that included rheumatoid arthritis, fibromyalgia, diabetes mellitus, hypertension, and chronic pain, for which she was receiving high doses of opioid analgesics, postsurgical pain management was a concern and she was considered a candidate for multimodal analgesia. At initiation of surgery, 50mL of lidocaine and epinephrine was infiltrated around the port sites. At the conclusion, 25mL of normal sterile saline was added to a 20mL vial of liposome bupivacaine (266mg) and injected around the port sites and at the site of liver retraction. Laparoscopic sleeve gastrectomy was successfully completed. Our patient was discharged to the postanesthesia care unit for approximately four hours before discharge to the surgical floor with a pain score of 5 (11-point scale; 0 = no pain, 10 = worst possible pain). Her postoperative course was uneventful; no adverse events were recorded during surgery or during the remainder of her hospital stay. Our patient was discharged on the same opioid regimen used previously for control of her preexisting chronic pain. Conclusions Liposome bupivacaine use in this morbidly obese

  16. Painful Issues in Pain Prediction.

    PubMed

    Hu, Li; Iannetti, Gian Domenico

    2016-04-01

    How perception of pain emerges from neural activity is largely unknown. Identifying a neural 'pain signature' and deriving a way to predict perceived pain from brain activity would have enormous basic and clinical implications. Researchers are increasingly turning to functional brain imaging, often applying machine-learning algorithms to infer that pain perception occurred. Yet, such sophisticated analyses are fraught with interpretive difficulties. Here, we highlight some common and troublesome problems in the literature, and suggest methods to ensure researchers draw accurate conclusions from their results. Since functional brain imaging is increasingly finding practical applications with real-world consequences, it is critical to interpret brain scans accurately, because decisions based on neural data will only be as good as the science behind them. PMID:26898163

  17. Pharmacological pain management in chronic pancreatitis

    PubMed Central

    Olesen, Søren S; Juel, Jacob; Graversen, Carina; Kolesnikov, Yuri; Wilder-Smith, Oliver HG; Drewes, Asbjørn M

    2013-01-01

    Intense abdominal pain is a prominent feature of chronic pancreatitis and its treatment remains a major clinical challenge. Basic studies of pancreatic nerves and experimental human pain research have provided evidence that pain processing is abnormal in these patients and in many cases resembles that seen in neuropathic and chronic pain disorders. An important ultimate outcome of such aberrant pain processing is that once the disease has advanced and the pathophysiological processes are firmly established, the generation of pain can become self-perpetuating and independent of the initial peripheral nociceptive drive. Consequently, the management of pain by traditional methods based on nociceptive deafferentation (e.g., surgery and visceral nerve blockade) becomes difficult and often ineffective. This novel and improved understanding of pain aetiology requires a paradigm shift in pain management of chronic pancreatitis. Modern mechanism based pain treatments taking into account altered pain processing are likely to increasingly replace invasive therapies targeting the nociceptive source, which should be reserved for special and carefully selected cases. In this review, we offer an overview of the current available pharmacological options for pain management in chronic pancreatitis. In addition, future options for pain management are discussed with special emphasis on personalized pain medicine and multidisciplinarity. PMID:24259960

  18. Subjective pain perception mediated by alpha rhythms.

    PubMed

    Peng, Weiwei; Babiloni, Claudio; Mao, Yanhui; Hu, Yong

    2015-07-01

    Suppression of spontaneous alpha oscillatory activities, interpreted as cortical excitability, was observed in response to both transient and tonic painful stimuli. The changes of alpha rhythms induced by pain could be modulated by painful sensory inputs, experimental tasks, and top-down cognitive regulations such as attention. The temporal and spatial characteristics, as well as neural functions of pain induced alpha responses, depend much on how these factors contribute to the observed alpha event-related desynchronization/synchronization (ERD/ERS). How sensory-, task-, and cognitive-related changes of alpha oscillatory activities interact in pain perception process is reviewed in the current study, and the following conclusions are made: (1) the functional inhibition hypothesis that has been proposed in auditory and visual modalities could be applied also in pain modality; (2) the neural functions of pain induced alpha ERD/ERS were highly dependent on the cortical regions where it is observed, e.g., somatosensory cortex alpha ERD/ERS in pain perception for painful stimulus processing; (3) the attention modulation of pain perception, i.e., influences on the sensory and affective dimensions of pain experience, could be mediated by changes of alpha rhythms. Finally, we propose a model regarding the determinants of pain related alpha oscillatory activity, i.e., sensory-discriminative, affective-motivational, and cognitive-modulative aspects of pain experience, would affect and determine pain related alpha oscillatory activities in an integrated way within the distributed alpha system. PMID:26026894

  19. [Myofascial pain syndrome--fascial muscle pain].

    PubMed

    Partanen, Juhani; Ojala, Tuula; Arokoski, Jari P A

    2010-01-01

    Symptoms of myofascial pain syndrome, i.e. fascial muscle pain may occur in several areas of the body, particularly in the neck-shoulder region. The muscle pain symptom in the neck-shoulder region is commonly termed tension neck pain or nonspecific neck pain, but myofascial pain syndrome can also be distinguished into its own diagnosis. This review deals with the clinical picture of myofascial pain syndrome along with pathophysiological hypotheses and treatment options.

  20. Measuring Bragg gratings in multimode optical fibers.

    PubMed

    Schmid, Markus J; Müller, Mathias S

    2015-03-23

    Fiber Bragg gratings (FBG) in multimode optical fibers provide a means for cost-effictive devices resulting in simplified and robust optic sensor systems. Parasitic mode effects in optical components of the entire measurement system strongly influence the measured multi-resonance reflection spectrum. Using a mode transfer matrix formalism we can describe these complex mode coupling effects in multimode optical systems in more detail. We demonstrate the accordance of the theory by two experiments. With this formalism it is possible to understand and optimize mode effects in multimode fiber optic systems. PMID:25837146

  1. Multimodality Molecular Imaging of the Lung

    PubMed Central

    Chen, Delphine L.; Kinahan, Paul E.

    2010-01-01

    The continued progression of chronic lung disease despite current treatment options has led to the increasing evaluation of molecular imaging tools for diagnosis, treatment planning, drug discovery, and therapy monitoring. Concurrently the development of multimodality PET/CT, SPECT/CT, and MRI/PET scanners has opened up the potential for more sophisticated imaging biomarker probes. Here we review the potential uses of multimodality imaging tools, the established uses of molecular imaging in non-oncologic lung pathophysiology and drug discovery, and some of the technical challenges in multimodality molecular imaging of the lung. PMID:21105145

  2. Encapsulation of carvacrol, a monoterpene present in the essential oil of oregano, with β-cyclodextrin, improves the pharmacological response on cancer pain experimental protocols.

    PubMed

    Guimarães, Adriana Gibara; Oliveira, Marlange Almeida; Alves, Rafael dos Santos; Menezes, Paula dos Passos; Serafini, Mairim Russo; Araújo, Adriano Antunes de Souza; Bezerra, Daniel Pereira; Quintans Júnior, Lucindo José

    2015-02-01

    Cancer pain is a major public health problem worldwide due to the strong impact on the quality of life of patients and side effects of the existing therapeutic options. Monoterpenes, as carvacrol (CARV), have been extensively studied about their therapeutic properties, especially their importance in the control of painful conditions and inflammation, which can be improved through the use of inclusion complexes of β-cyclodextrin (β-CD). We evaluated the effect of encapsulation of CARV in β-CD (CARV/β-CD) on the nociception induced by tumor cells (Sarcoma 180) in rodents. Inclusion complexes were prepared in two different procedures and characterized through thermal analysis and scanning electron microscopy. CARV/β-CD complex was administered (50 mg/kg, p.o.) in mice with tumor on the hind paw and was able to reduce the hyperalgesia (von Frey) during 24 h, unlike the free CARV (100 mg/kg, p.o.), which promoted effects until 9 h. Administration on alternate days of complex of CARV/β-CD (12.5-50 mg/kg, p.o.) reduced hyperalgesia, as well as spontaneous and palpation-induced nociception. However, pure CARV (50 mg/kg) did not cause significant changes in nociceptive responses. Together, these results produced evidence that the encapsulation of carvacrol in β-cyclodextrin can be useful for the development of new options for pain management. PMID:25557507

  3. Encapsulation of carvacrol, a monoterpene present in the essential oil of oregano, with β-cyclodextrin, improves the pharmacological response on cancer pain experimental protocols.

    PubMed

    Guimarães, Adriana Gibara; Oliveira, Marlange Almeida; Alves, Rafael dos Santos; Menezes, Paula dos Passos; Serafini, Mairim Russo; Araújo, Adriano Antunes de Souza; Bezerra, Daniel Pereira; Quintans Júnior, Lucindo José

    2015-02-01

    Cancer pain is a major public health problem worldwide due to the strong impact on the quality of life of patients and side effects of the existing therapeutic options. Monoterpenes, as carvacrol (CARV), have been extensively studied about their therapeutic properties, especially their importance in the control of painful conditions and inflammation, which can be improved through the use of inclusion complexes of β-cyclodextrin (β-CD). We evaluated the effect of encapsulation of CARV in β-CD (CARV/β-CD) on the nociception induced by tumor cells (Sarcoma 180) in rodents. Inclusion complexes were prepared in two different procedures and characterized through thermal analysis and scanning electron microscopy. CARV/β-CD complex was administered (50 mg/kg, p.o.) in mice with tumor on the hind paw and was able to reduce the hyperalgesia (von Frey) during 24 h, unlike the free CARV (100 mg/kg, p.o.), which promoted effects until 9 h. Administration on alternate days of complex of CARV/β-CD (12.5-50 mg/kg, p.o.) reduced hyperalgesia, as well as spontaneous and palpation-induced nociception. However, pure CARV (50 mg/kg) did not cause significant changes in nociceptive responses. Together, these results produced evidence that the encapsulation of carvacrol in β-cyclodextrin can be useful for the development of new options for pain management.

  4. Chronic pain self-management for older adults: a randomized controlled trial [ISRCTN11899548

    PubMed Central

    Ersek, Mary; Turner, Judith A; Cain, Kevin C; Kemp, Carol A

    2004-01-01

    Background Chronic pain is a common and frequently disabling problem in older adults. Clinical guidelines emphasize the need to use multimodal therapies to manage persistent pain in this population. Pain self-management training is a multimodal therapy that has been found to be effective in young to middle-aged adult samples. This training includes education about pain as well as instruction and practice in several management techniques, including relaxation, physical exercise, modification of negative thoughts, and goal setting. Few studies have examined the effectiveness of this therapy in older adult samples. Methods/Design This is a randomized, controlled trial to assess the effectiveness of a pain self-management training group intervention, as compared with an education-only control condition. Participants are recruited from retirement communities in the Pacific Northwest of the United States and must be 65 years or older and experience persistent, noncancer pain that limits their activities. The primary outcome is physical disability, as measured by the Roland-Morris Disability Questionnaire. Secondary outcomes are depression (Geriatric Depression Scale), pain intensity (Brief Pain Inventory), and pain-related interference with activities (Brief Pain Inventory). Randomization occurs by facility to minimize cross-contamination between groups. The target sample size is 273 enrolled, which assuming a 20% attrition rate at 12 months, will provide us with 84% power to detect a moderate effect size of .50 for the primary outcome. Discussion Few studies have investigated the effects of multimodal pain self-management training among older adults. This randomized controlled trial is designed to assess the efficacy of a pain self-management program that incorporates physical and psychosocial pain coping skills among adults in the mid-old to old-old range. PMID:15285783

  5. Effects of Multimodal Analgesia on the Success of Mouse Embryo Transfer Surgery

    PubMed Central

    Parker, John M.; Austin, Jamie; Wilkerson, James; Carbone, Larry

    2011-01-01

    Multimodal analgesia is promoted as the best practice pain management for invasive animal research procedures. Universal acceptance and incorporation of multimodal analgesia requires assessing potential effects on study outcome. The focus of this study was to assess effects on embryo survival after multimodal analgesia comprising an opioid and nonsteroidal antiinflammatory drug (NSAID) compared with opioid-only analgesia during embryo transfer procedures in transgenic mouse production. Mice were assigned to receive either carprofen (5 mg/kg) with buprenorphine (0.1 mg/kg; CB) or vehicle with buprenorphine (0.1 mg/kg; VB) in a prospective, double-blinded placebo controlled clinical trial. Data were analyzed in surgical sets of 1 to 3 female mice receiving embryos chimeric for a shared targeted embryonic stem-cell clone and host blastocyst cells. A total of 99 surgical sets were analyzed, comprising 199 Crl:CD1 female mice and their 996 offspring. Neither yield (pups weaned per embryo implanted in the surgical set) nor birth rate (average number of pups weaned per dam in the set) differed significantly between the CB and VB conditions. Multimodal opioid–NSAID analgesia appears to have no significant positive or negative effect on the success of producing novel lines of transgenic mice by blastocyst transfer. PMID:21838973

  6. Randomized clinical trial of multimodal physiotherapy treatment compared to overnight lidocaine ointment in women with provoked vestibulodynia: Design and methods.

    PubMed

    Morin, Mélanie; Dumoulin, Chantale; Bergeron, Sophie; Mayrand, Marie-Hélène; Khalifé, Samir; Waddell, Guy; Dubois, Marie-France

    2016-01-01

    Provoked vestibulodynia (PVD) is a highly prevalent and debilitating condition yet its management relies mainly on non-empirically validated interventions. Among the many causes of PVD, there is growing evidence that pelvic floor muscle (PFM) dysfunctions play an important role in its pathophysiology. Multimodal physiotherapy, which addresses these dysfunctions, is judged by experts to be highly effective and is recommended as a first-line treatment. However, the effectiveness of this promising intervention has been evaluated through only two small uncontrolled trials. The proposed bi-center, single-blind, parallel group, randomized controlled trial (RCT) aims to evaluate the efficacy of multimodal physiotherapy and compare it to a frequently used first-line treatment, topical overnight application of lidocaine, in women with PVD. A total of 212 women diagnosed with PVD according to a standardized protocol were eligible for the study and were randomly assigned to either multimodal physiotherapy or lidocaine treatment for 10weeks. The primary outcome measure is pain during intercourse (assessed with a numerical rating scale). Secondary measures include sexual function, pain quality, psychological factors (including pain catastrophizing, anxiety, depression and fear of pain), PFM morphology and function, and patients' global impression of change. Assessments are made at baseline, post-treatment and at the 6-month follow-up. This manuscript presents and discusses the rationale, design and methodology of the first RCT investigating physiotherapy in comparison to a commonly prescribed first-line treatment, overnight topical lidocaine, for women with PVD.

  7. 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.

  8. Depressive symptoms and pain evaluations among persons with chronic pain: catastrophizing, but not pain acceptance, shows significant effects.

    PubMed

    Richardson, Elizabeth J; Ness, Timothy J; Doleys, Daniel M; Baños, James H; Cianfrini, Leanne; Richards, J Scott

    2009-12-15

    Cognitive factors such as catastrophic thoughts regarding pain, and conversely, one's acceptance of that pain, may affect emotional functioning among persons with chronic pain conditions. The aims of the present study were to examine the effects of both catastrophizing and acceptance on affective ratings of experimentally induced ischemic pain and also self-reports of depressive symptoms. Sixty-seven individuals with chronic back pain completed self-report measures of catastrophizing, acceptance, and depressive symptoms. In addition, participants underwent an ischemic pain induction procedure and were asked to rate the induced pain. Catastrophizing showed significant effects on sensory and intensity but not affective ratings of the induced pain. Acceptance did not show any significant associations, when catastrophizing was also in the model, with any form of ratings of the induced pain. Catastrophizing, but not acceptance, was also significantly associated with self-reported depressive symptoms when these two variables were both included in a regression model. Overall, results indicate negative thought patterns such as catastrophizing appear to be more closely related to outcomes of perceived pain severity and affect in persons with chronic pain exposed to an experimental laboratory pain stimulus than does more positive patterns as reflected in measures of acceptance.

  9. Low back pain - acute

    MedlinePlus

    Backache; Low back pain; Lumbar pain; Pain - back; Acute back pain; Back pain - new; Back pain - short-term; Back strain - new ... lower back supports most of your body's weight. Low back pain is the number two reason that Americans see ...

  10. [Forefoot pain].

    PubMed

    Damiano, Joël

    2010-03-20

    Forefoot chronic pain is a frequent problem in daily clinical practice. Mechanical pathology of the forefoot, usually called static metatarsalgia, represents the most frequent reason for consultation in pathology of the foot. The cause is a functionnal disorder or anatomic derangement of the forefoot architecture. Metatarsalgia can originate from a wide range of affections. Etiologies of chronic pain are described from medial to lateral with first ray pathologies (hallux valgus, hallux rigidus and sesamoid pathology) and first ray insufficiency, pathologies of the second, third and fourth ray and intermetatarsal spaces (second ray syndrome, Freiberg's disease, Morton neuroma, stress or bone insufficiency metatarsal fractures, intermetatarsal bursitis) and fifth ray pathology (lateral bursitis, quintus varus). Sometimes forefoot pain could also be caused by chronic inflammatory rheumatic diseases (rheumatoid and psoriatic arthritis) with a risk of structural metatarsophalangeal joints alteration. The pathology of the toes can, more rarely, explain a forefoot pain. So, several pathologic conditions can produce forefoot pain and the diagnostic approach must always be based on the anamnesis and clinical examination. In a second time if the cause is difficult to establish based solely on clinical findings, radiography and ultrasonography are today the most usefull auxiliary investigations.

  11. Multimodal unattended ground sensor (MMUGS)

    NASA Astrophysics Data System (ADS)

    Zong, Lei; Houser, Jeff; Damarla, T. Raju

    2006-05-01

    The U.S. Army Research Laboratory has developed a real-time multi-modal sensor for the purpose of personnel detection in urban terrain. Possible system usage includes force protection and sniper early warning. The sensor system includes a network of MMUGS sensors, a third-party gateway and user interface device. A MMUGS sensor consists of the following functions: sensing, processing, and communication. Each sensor is composed of multiple sensing modalities-acoustic, passive-infrared, and seismic. A MMUGS sensor is designed to be low cost and power efficient. This paper will first present an overview of the sensor architecture and then provide detailed descriptions of sub components. The paper will conclude with a detailed analysis of system performance. This paper is intended to provide details of the design, integration, and implementation of a MMUGS unit, and demonstrate the overall sensor system performance. This paper does not discuss the network aspect of the system and its affect on performance.

  12. Brain Multimodality Monitoring: Updated Perspectives

    PubMed Central

    Roh, David

    2016-01-01

    The challenges posed by acute brain injury (ABI) involve the management of the initial insult in addition to downstream inflammation, edema, and ischemia that can result in secondary brain injury (SBI). SBI is often subclinical, but can be detected through physiologic changes. These changes serve as a surrogate for tissue injury/cell death and are captured by parameters measured by various monitors that measure intracranial pressure (ICP), cerebral blood flow (CBF), brain tissue oxygenation (PbtO2), cerebral metabolism, and electrocortical activity. In the ideal setting, multimodality monitoring (MMM) integrates these neurological monitoring parameters with traditional hemodynamic monitoring and the physical exam, presenting the information needed to clinicians who can intervene before irreversible damage occurs. There are now consensus guidelines on the utilization of MMM, and there continue to be new advances and questions regarding its use. In this review, we examine these recommendations, recent evidence for MMM, and future directions for MMM. PMID:27095434

  13. Multimodality treatment for cardiac angiosarcoma.

    PubMed

    Wang, Meng; Fu, Ganglan; Jiang, Huiqi; Zeng, Kuan; Hua, Ping

    2014-01-01

    Primary cardiac angiosarcoma is a rare and highly malignant condition. Besides performing complete surgical excision, it remains controversial as to whether survival can be improved with additional treatment. We herein describe a 30-year-old man with a right atrial angiosarcoma. He underwent two operations for the resection of the primary lesion, and the patient's metastatic lesions involved an intestinal segment. With chemotherapy, radiotherapy, and molecular targeted therapy, he survived for 33 months. The literature describing adjuvant therapy for cardiac angiosarcoma, which is mostly case reports, is also reviewed. In conclusion, the limited evidence suggests that multimodality treatment for cardiac angiosarcoma is a beacon of hope to improve the survival of such patients.

  14. Multimode waveguide based directional coupler

    NASA Astrophysics Data System (ADS)

    Ahmed, Rajib; Rifat, Ahmmed A.; Sabouri, Aydin; Al-Qattan, Bader; Essa, Khamis; Butt, Haider

    2016-07-01

    The Silicon-on-Insulator (SOI) based platform overcomes limitations of the previous copper and fiber based technologies. Due to its high index difference, SOI waveguide (WG) and directional couplers (DC) are widely used for high speed optical networks and hybrid Electro-Optical inter-connections; TE00-TE01, TE00-TE00 and TM00-TM00 SOI direction couplers are designed with symmetrical and asymmetrical configurations to couple with TE00, TE01 and TM00 in a multi-mode semi-triangular ring-resonator configuration which will be applicable for multi-analyte sensing. Couplers are designed with effective index method and their structural parameters are optimized with consideration to coupler length, wavelength and polarization dependence. Lastly, performance of the couplers are analyzed in terms of cross-talk, mode overlap factor, coupling length and coupling efficiency.

  15. Psychosocial perspectives in the treatment of pediatric chronic pain

    PubMed Central

    2012-01-01

    Chronic pain in children and adolescents is associated with major disruption to developmental experiences crucial to personal adjustment, quality of life, academic, vocational and social success. Caring for these patients involves understanding cognitive, affective, social and family dynamic factors associated with persistent pain syndromes. Evaluation and treatment necessitate a comprehensive multimodal approach including psychological and behavioral interventions that maximize return to more developmentally appropriate physical, academic and social activities. This article will provide an overview of major psychosocial factors impacting on pediatric pain and disability, propose an explanatory model for conceptualizing the development and maintenance of pain and functional disability in medically difficult-to-explain pain syndromes, and review representative evidence-based cognitive behavioral and systemic treatment approaches for improving functioning in this pediatric population. PMID:22676345

  16. Fibromyalgia and Myofascial Pain Syndrome-A Dilemma

    PubMed Central

    Chandola, H C; Chakraborty, Arunangshu

    2009-01-01

    Summary Pain and fatigue associated to the musculoskeletal system are among the leading causes of patients to visit their physicians and nearly one-third of such patients suffer from fibromyalgia. Fibromyalgia syndrome (FMS) is a chronic debilitating disorder characterized by widespread pain with tenderness in specific areas, leading to fatigue, headache and sleep disorder. Myofascial Pain Syndrome (MPS), is also a localized musculoskeletal pain producing condition whose diagnostic and management criteria differ from FMS but still considered by many only a subtype of FMS. Till date no exact cause has been held responsible for these painful conditions, therefore treatment of these disorders is always a challenge. The therapies are not precise but multimodal including pharmacological and alternative approaches. This article describes the existing knowledge pertaining to these conditions in regard of causative factors diagnosis and management. PMID:20640108

  17. Committee Opinion No 673 Summary: Persistent Vulvar Pain.

    PubMed

    2016-09-01

    Persistent vulvar pain is a complex disorder that frequently is frustrating to the patient and the clinician. It can be difficult to treat and rapid resolution is unusual, even with appropriate therapy. Vulvar pain can be caused by a specific disorder or it can be idiopathic. Idiopathic vulvar pain is classified as vulvodynia. Although optimal treatment remains unclear, consider an individualized, multidisciplinary approach to address all physical and emotional aspects possibly attributable to vulvodynia. Specialists who may need to be involved include sexual counselors, clinical psychologists, physical therapists, and pain specialists. Patients may perceive this approach to mean the practitioner does not believe their pain is "real"; thus, it is important to begin any treatment approach with a detailed discussion, including an explanation of the diagnosis and determination of realistic treatment goals. Future research should aim at evaluating a multimodal approach in the treatment of vulvodynia, along with more research on the etiologies of vulvodynia. PMID:27548552

  18. Multiphoton ionization of hydrogen by a strong multimode field

    SciTech Connect

    Basile, S.; Trombetta, F.; Ferrante, G.; Burlon, R.; Leone, C.

    1988-02-01

    Multiphoton ionization of hydrogen atoms by a strong multimode field when several final continuum states are populated is treated theoretically within a model based on the S-matrix formalism. The field is taken in dipole approximation, with zero bandwidth. Field-dressed Coulomb wave functions are used for the electron final states. Ionization rates are calculated for different numbers of photons absorbed in excess of the minimum number required to go into the continuum. In general, the calculated quantities are in good qualitative agreement with the corresponding experimental observations.

  19. Multimode terahertz-wave generation using coherent Cherenkov radiation

    SciTech Connect

    Kan, K.; Yang, J.; Ogata, A.; Kondoh, T.; Norizawa, K.; Yoshida, Y.

    2011-12-05

    Multimode terahertz(THz)-wave generation using coherent Cherenkov radiation (CCR) was investigated. The frequency spectra of CCR, which utilized a metal-wrapped hollow dielectric tube of 7 mm outer radius and a picosecond electron bunch of 27 MeV beam energy, were measured by a Michelson interferometer with a 4.2 K silicon bolometer. In this study, discrete spectral components at frequencies of 0.09, 0.14, and 0.36 THz were observed experimentally and explained as transverse magnetic (TM) modes of TM{sub 03}, TM{sub 04}, and TM{sub 09}, respectively, according to a theoretical calculation for the tube.

  20. Propagation and radiation characteristics of a multimode corrugated waveguide feedhorn

    NASA Technical Reports Server (NTRS)

    Hoppe, D.

    1985-01-01

    A prototype of the multimode corrugated feedhorn which will be used in the 400 kW CW Ka-band radar system is described. A rough design is done using coupled mode theory and standard corrugated waveguide modes. A more exact analysis using mode matching techniques is then used which takes into account the effect of a finite number of corrugations per wavelength and determines the modes which are reflected from the device. A prototype feedhorn has been constructed and measured. These experimental results are then compared to the theoretical predictions which agree satisfactorily closely.

  1. Propagation and radiation characteristics of a multimode corrugated waveguide feedhorn

    NASA Astrophysics Data System (ADS)

    Hoppe, D.

    1985-08-01

    A prototype of the multimode corrugated feedhorn which will be used in the 400 kW CW Ka-band radar system is described. A rough design is done using coupled mode theory and standard corrugated waveguide modes. A more exact analysis using mode matching techniques is then used which takes into account the effect of a finite number of corrugations per wavelength and determines the modes which are reflected from the device. A prototype feedhorn has been constructed and measured. These experimental results are then compared to the theoretical predictions which agree satisfactorily closely.

  2. Correlation steering in the angularly multimode Raman atomic memory.

    PubMed

    Mazelanik, Mateusz; Dąbrowski, Michał; Wasilewski, Wojciech

    2016-09-19

    We present the possibility of steering the direction of correlations between the off-resonant Raman scattered photons from the angularly multimode atomic memory based on warm rubidium vapors. Using acousto-optic deflectors (AOD) driven by different modulation frequencies, we experimentally change the angle of incidence of the laser beams on the atomic ensemble. By performing correlation measurements for various deflection angles, we verify that we can choose the anti-Stokes light propagation direction independently of the correlated Stokes scattered light in a continuous way. As a result we can select the spatial mode of photons retrieved from the memory, which may be important for future development of quantum information processing.

  3. Quantum teleportation of nonclassical wave packets: An effective multimode theory

    SciTech Connect

    Benichi, Hugo; Takeda, Shuntaro; Lee, Noriyuki; Furusawa, Akira

    2011-07-15

    We develop a simple and efficient theoretical model to understand the quantum properties of broadband continuous variable quantum teleportation. We show that, if stated properly, the problem of multimode teleportation can be simplified to teleportation of a single effective mode that describes the input state temporal characteristic. Using that model, we show how the finite bandwidth of squeezing and external noise in the classical channel affect the output teleported quantum field. We choose an approach that is especially relevant for the case of non-Gaussian nonclassical quantum states and we finally back-test our model with recent experimental results.

  4. Modeling and optimization of multimode fused fiber combiners

    NASA Astrophysics Data System (ADS)

    Liu, Yu; Yu, Hao; Califano, Alessio; Braglia, Andrea; Perrone, Guido

    2016-03-01

    An effective method to predict the performance of multimode fused fiber combiners is presented. The realization of high power devices is strongly affected by the specific application, for instance whether used in fiber or in direct-diode lasers, and thus usually requires costly and time-consuming trial-and-error procedures. The proposed approach, which is based on ray tracing and statistical analysis, allows analyzing a-priori the impact of fiber dimensions, combiner geometry, glass material properties and laser beam quality on the coupling efficiency, therefore reducing the fabrication runs. Examples of application to 7-to-1 and 19-to-1 combiners are given and compared with experimental results.

  5. [Pain management in patients with liver cirrhosis].

    PubMed

    Ojeda, Antonio; Moreno, Luis A

    2014-01-01

    Pain management in patients with liver cirrhosis is a real challenge and is often inadequate due to a lack of therapeutic efficacy or the high incidence of adverse effects. The focus of treatment differs depending on whether the pain is acute or chronic and involves understanding the causative pathophysiological mechanism. Analgesics should be started with the minimum effective dose and should be titrated slowly with avoidance of polypharmacy. Adverse effects must be monitored, especially sedation and constipation, which predispose the patient to the development of hepatic encephalopathy. The first-line drug is paracetamol, which is safe at doses of 2-3g/day. Non-steroidal anti-inflammatory agents are contraindicated because they can cause acute renal failure and/or gastrointestinal bleeding. Tramadol is a safe option for moderate-severe pain. The opioids with the best safety profile are fentanyl and hydromorphone, with methadone as an alternative. Topical treatment can reduce oral drug consumption. In neuropathic pain the first-line therapeutic option is gabapentin. The use of antidepressants such as amitriptyline can be considered in some patients. Interventional techniques are a valuable tool in moderate to severe pain, since they allow a reduction in drug therapy and consequently its adverse effects. Psychological treatment, physical therapy and rehabilitation should be considered as part of multimodality therapy in the management of chronic pain.

  6. High-temperature distributed sensor system via BOTDA and multimode gold-coated fiber

    NASA Astrophysics Data System (ADS)

    Ruiz-Lombera, R.; Laarossi, I.; Mirapeix, J.; Quintela, M. A.; Lopez-Higuera, J. M.

    2016-05-01

    A high-temperature distributed sensor solution based on a Brillouin Optical Time Domain Analyzer and a multimode gold-coated fiber is presented and experimentally validated in this paper. Distributed temperature measurements up to 600°C will be demonstrated.

  7. Developing a "Big Picture": Effects of Collaborative Construction of Multimodal Representations in History

    ERIC Educational Resources Information Center

    Prangsma, Maaike E.; Van Boxtel, Carla A. M.; Kanselaar, Gellof

    2008-01-01

    Many pupils have difficulties with the abstract verbal information in history lessons. In this study we assessed the value of active construction of multimodal representations of historical phenomena. In an experimental study we compared the learning outcomes of pupils who co-constructed textual representations, visual-textual representations, or…

  8. The Effect of a Pretest in an Interactive, Multimodal Pretraining System for Learning Science Concepts

    ERIC Educational Resources Information Center

    Bos, Floris A. B. H.; Terlouw, Cees; Pilot, Albert

    2009-01-01

    In line with the cognitive theory of multimedia learning by Moreno and Mayer (2007), an interactive, multimodal learning environment was designed for the pretraining of science concepts in the joint area of physics, chemistry, biology, applied mathematics, and computer sciences. In the experimental set up, a pretest was embedded in order to…

  9. Pain management for the cancer patient - current practice and future developments.

    PubMed

    Auret, Kirsten; Schug, Stephan A

    2013-12-01

    Anaesthesiologists will be asked to provide pain management for cancer patients in the absence of more specialised services, when interventional techniques are indicated and in the postoperative period. In all these settings, the complexity of cancer pain and its psychosocial connotations need to be considered to provide appropriate and holistic care. Principles of systemic pain management, effective in most patients, continue to follow established guidelines; identification of neuropathic pain and its appropriate treatment is important here. Interventional pain relief is required in a minority of cancer patients, but it should be considered when appropriate and then done with best available expertise. Neurolytic procedures have lost importance here over the years. Postoperative pain management should be multimodal with consideration of regional techniques when applicable. In managing postoperative pain in cancer patients, opioid tolerance needs to be addressed to avoid withdrawal and poor analgesia. Preventive techniques aiming to reduce chronic postoperative pain should be considered. PMID:24267557

  10. Chronic Pain Medicines

    MedlinePlus

    ... Treatment of chronic pain usually involves medicines and therapy. Medicines used for chronic pain include pain relievers, antidepressants and anticonvulsants. Different types of medicines help ...

  11. Multi-Modal Treatment of Nocturnal Enuresis.

    ERIC Educational Resources Information Center

    Mohr, Caroline; Sharpley, Christopher F.

    1988-01-01

    The article reports a multimodal treatment of nocturnal enuresis and anxious behavior in a mildly mentally retarded woman. Behavioral treatment and removal of caffeine from the subject's diet eliminated both nocturnal enuresis and anxious behavior. (Author/DB)

  12. Multi-mode horn antenna simulation

    NASA Technical Reports Server (NTRS)

    Dod, L. R.; Wolf, J. D.

    1980-01-01

    Radiation patterns were computed for a circular multimode horn antenna using waveguide electric field radiation expressions. The circular multimode horn was considered as a possible reflector feed antenna for the Large Antenna Multifrequency Microwave Radiometer (LAMMR). This horn antenna uses a summation of the TE sub 11 deg and TM sub 11 deg modes to generate far field primary radiation patterns with equal E and H plane beamwidths and low sidelobes. A computer program for the radiation field expressions using the summation of waveguide radiation modes is described. The sensitivity of the multimode horn antenna radiation patterns to phase variations between the two modes is given. Sample radiation pattern calculations for a reflector feed horn for LAMMR are shown. The multimode horn antenna provides a low noise feed suitable for radiometric applications.

  13. Multimodal biometrics system based on face profile and ear

    NASA Astrophysics Data System (ADS)

    Youssef, Iman S.; Abaza, Ayman A.; Rasmy, Mohamed E.; Badawi, Ahmed M.

    2014-05-01

    Face recognition from a side profile view, has recently received significant attention in the literature. Even though current face recognition systems have reached a certain level of maturity at angles up to 30 degrees, their success is still limited with side profile angles. This paper presents an efficient technique for the fusion of face profile and ear biometrics. We propose to use a Block-based Local Binary Pattern (LBP) to generate the features for recognition from face profile images and ear images. These feature distributions are then fused at the score level using simple mean rule. Experimental results show that the proposed multimodal system can achieve 97:98% recognition performance, compared to unimodal biometrics of face profile 96.76%, and unimodal biometrics of ear 96.95%, details in the Experimental Results Section. Comparisons with other multimodal systems used in the literature, like Principal Component Analysis (PCA), Full-space Linear Discriminant Analysis (FSLDA) and Kernel Fisher discriminant analysis (KFDA), are presented in the Experimental Results Section.

  14. Multimode fiber laser for simultaneous measurement of strain and temperature based on beat frequency demodulation.

    PubMed

    Gao, Liang; Chen, Lin; Huang, Long; Chen, Xiangfei

    2012-09-24

    A multimode fiber laser sensor system for simultaneous measurement of strain and temperature is proposed and demonstrated. Because of the long cavity and birefringence, longitudinal mode beat frequency and polarization mode beat frequency are achieved in the beat frequency signals of the multimode fiber laser. The strain and temperature can be obtained by monitoring both of them for their different strain and temperature responses. The experimental measurement errors are within ± 16.2 με and ± 1.9 °C. The usage of only one fiber laser and one demodulation system makes the system simple, cost-effective and portable.

  15. User-oriented summary extraction for soccer video based on multimodal analysis

    NASA Astrophysics Data System (ADS)

    Liu, Huayong; Jiang, Shanshan; He, Tingting

    2011-11-01

    An advanced user-oriented summary extraction method for soccer video is proposed in this work. Firstly, an algorithm of user-oriented summary extraction for soccer video is introduced. A novel approach that integrates multimodal analysis, such as extraction and analysis of the stadium features, moving object features, audio features and text features is introduced. By these features the semantic of the soccer video and the highlight mode are obtained. Then we can find the highlight position and put them together by highlight degrees to obtain the video summary. The experimental results for sports video of world cup soccer games indicate that multimodal analysis is effective for soccer video browsing and retrieval.

  16. [Psychological assessment and psychotherapy for chronic pain in the elderly].

    PubMed

    Mattenklodt, P; Leonhardt, C

    2015-08-01

    Systematic reviews of psychosocial assessment and effectiveness of psychotherapy for chronic pain syndromes in older patients are rare. However, it is of particular importance to consider the psychosocial aspects of elderly people with chronic pain. This narrative review describes recommended German-language assessments of the psychosocial dimensions of pain and summarizes existing studies of psychological therapy approaches for chronic pain in old age. Effective psychometric instruments are available for the assessment of cognitive function, pain-specific attitudes, depression, fear of falling, interpersonal processes and social activities, pain management, pain acceptance, disability, psychological well-being, and quality of life. Further experience with the use of these instruments with cognitively impaired or geriatric patients is required. The efficacy of age-adapted cognitive behavioral therapy and multimodal therapy for older patients has been documented. However, there is often a lack of supporting documentation about important result parameters (e.g., quality of life, functioning in everyday life, or pain acceptance). Overall, chronic pain in elderly people requires a biopsychosocial-spiritual model of pain. More attention should be given in research and daily practice to religiosity/spirituality as a possible means of coping, while mindfulness- and acceptance-based therapies should be further explored. PMID:26024645

  17. Safety, tolerability, pharmacokinetics, and effects on human experimental pain of the selective ionotropic glutamate receptor 5 (iGluR5) antagonist LY545694 in healthy volunteers.

    PubMed

    Petersen, Karin L; Iyengar, Smriti; Chappell, Amy S; Lobo, Evelyn D; Reda, Haatem; Prucka, William R; Verfaille, Steven J

    2014-05-01

    The objective of this study was to establish in healthy volunteers the maximally tolerated multiple dose (MTMD) of the ionotropic glutamate receptor 5 antagonist LY545694 (part A), and to investigate whether that dose had analgesic or antihyperalgesic effects in the brief thermal stimulation (BTS) pain model (Part B). Part A was a double-blind, placebo-controlled study in 3 groups of 10 healthy men. To simulate an extended-release formulation, study drug was administered orally over 6hours (12 equally divided aliquots at 30-minute intervals). Part B was a double-blind, placebo-controlled, double-dummy, 3-way crossover study in 27 healthy men. At each of the 3 study periods, subjects received either LY545694 (MTMD; as determined during part A) as a simulated, twice daily extended-release formulation for 4 doses over 3days, gabapentin (600mg 8hours apart; 6 doses over 3days; positive control), or matching placebo. The BTS model was induced twice with a 1-hour interval on each of the 2 study days, before drug administration and at the time of expected peak analgesia of LY545694. Plasma exposure for LY545694 was approximately linear over the 25- to 75-mg dose range. The MTMD of LY545694 was 25mg twice daily. Areas of secondary hyperalgesia were significantly smaller after administration of LY545694 and gabapentin compared with placebo (P<.0001 and P=.0004, respectively), but there was no difference between areas after administration of gabapentin and LY545694 (P=.400). Neither gabapentin nor LY545694 reduced the painfulness of skin heating during BTS model induction. The most common treatment-emergent adverse event was dizziness. The results of this study suggest that LY545694 should be explored further as a potential treatment for chronic pain involving neuronal sensitization.

  18. Gallic acid and exercise training improve motor function, nerve conduction velocity but not pain sense reflex after experimental sciatic nerve crush in male rats

    PubMed Central

    Hajimoradi, Maryam; Fazilati, Mohammad; Gharib-Naseri, Mohammad Kazem; Sarkaki, Alireza

    2015-01-01

    Objective: The aim of present study was to evaluate the effects of oral administration of gallic acid (GA) for 21 days alone and in combination with exercise on nerve conduction velocity and sensory and motor functions in rats with sciatic nerve crush. Materials and Methods: Seventy adult male Wistar rats (250-300 g) were divided randomly into 7 groups with 10 in each: 1) Control (Cont), 2) Crushed + Vehicle (Cr +Veh), 3-5) Crushed + gallic acid (Cr+GA) (50, 100, and 200 mg/kg/2 mL, orally), 6) Crushed + exercise (Cr+Exe), and 7) Crushed + exercise + effective dose of gallic acid (Cr+Exe +GA200) for 21 days. In order to establish an animal model of sciatic nerve crush, equivalent to 7 kg of force pressed on 2-3 mm of sciatic nerve for 30 s, three times with 30 s intervals. Pain sense reflex in hot plate, motor coordination in rotarod, and sciatic nerve conduction velocity (SNCV) in all groups were tested. Data were analyzed using one-way ANOVA followed by Tukey’s post hoc test and p<0.05 has assigned as the significant difference. Results: Pain threshold was increased significantly in untreated crushed rats while motor function and SNCV were decreased in all groups with nerve crush (p<0.05, p<0.01, p<0.001 vs. control). Pain reflex latency was not changed in treated groups. Motor coordination and SNCV were improved in groups Cr+GA200 and Cr+Exe + GA200 (p<0.05, p<0.01 vs. Cr+Veh). Conclusion: GA, dose-dependently, may have therapeutic potential to improve the peripheral nerve degeneration, which is most likely related, at least in part, to its antioxidant and therapeutic properties. PMID:26445710

  19. Peripheral antinociceptive action of mangiferin in mouse models of experimental pain: role of endogenous opioids, K(ATP)-channels and adenosine.

    PubMed

    Lopes, Synara C; da Silva, Ana Virginia L; Arruda, Bruno Rodrigues; Morais, Talita C; Rios, Jeison Barros; Trevisan, Maria Teresa S; Rao, Vietla S; Santos, Flávia A

    2013-09-01

    This study aimed to assess the possible systemic antinociceptive activity of mangiferin and to clarify the underlying mechanism, using the acute models of chemical (acetic acid, formalin, and capsaicin) and thermal (hot-plate and tail-flick) nociception in mice. Mangiferin at oral doses of 10 to 100 mg/kg evidenced significant antinociception against chemogenic pain in the test models of acetic acid-induced visceral pain and in formalin- and capsaicin-induced neuro-inflammatory pain, in a naloxone-sensitive manner, suggesting the participation of endogenous opiates in its mechanism. In capsaicin test, the antinociceptive effect of mangiferin (30 mg/kg) was not modified by respective competitive and non-competitive transient receptor potential vanilloid 1 (TRPV1) antagonists, capsazepine and ruthenium red, or by pretreatment with L-NAME, a non-selective nitric oxide synthase inhibitor, or by ODQ, an inhibitor of soluble guanylyl cyclase. However, mangiferin effect was significantly reversed by glibenclamide, a blocker of K(ATP) channels and in animals pretreated with 8-phenyltheophylline, an adenosine receptor antagonist. Mangiferin failed to modify the thermal nociception in hot-plate and tail-flick test models, suggesting that its analgesic effect is only peripheral but not central. The orally administered mangiferin (10-100 mg/kg) was well tolerated and did not impair the ambulation or the motor coordination of mice in respective open-field and rota-rod tests, indicating that the observed antinociception was unrelated to sedation or motor abnormality. The findings of this study suggest that mangiferin has a peripheral antinociceptive action through mechanisms that involve endogenous opioids, K(ATP)-channels and adenosine receptors.

  20. Rapid prototype modeling in a multimodality world

    NASA Astrophysics Data System (ADS)

    Bidaut, Luc; Madewell, John; Yasko, Alan

    2006-03-01

    Introduction: Rapid prototype modeling (RPM) has been used in medicine principally for bones - that are easily extracted from CT data sets - for planning orthopaedic, plastic or maxillo-facial interventions, and/or for designing custom prostheses and implants. Based on newly available technology, highly valuable multimodality approaches can now be applied to RPM, particularly for complex musculo-skeletal (MSK) tumors where multimodality often transcends CT alone. Methods: CT data sets are acquired for primary evaluation of MSK tumors in parallel with other modalities (e.g., MR, PET, SPECT). In our approach, CT is first segmented to provide bony anatomy for RPM and all other data sets are then registered to the CT reference. Parametric information relevant to the tumor's characterization is then extracted from the multimodality space and merged with the CT anatomy to produce a hybrid RPM-ready model. This model - that also accommodates digital multimodality visualization - is then produced on the latest generation of 3D printers, which permits both shapes and colors. Results: Multimodality models of complex MSK tumors have been physically produced on modern RPM equipment. This new approach has been found to be a clear improvement over the previously disconnected physical RPM and digital multimodality visualization. Conclusions: New technical developments keep opening doors to sophisticated medical applications that can directly impact the quality of patient care. Although this early work still deals with bones as base models for RPM, its use to encompass soft tissues is already envisioned for future approaches.

  1. Facts and Figures on Pain

    MedlinePlus

    ... adults. Common chronic pain complaints include headache, low back pain, cancer pain, arthritis pain, neurogenic pain (pain resulting ... Institute of Health Statistics survey indicated that low back pain was the most common (27%), followed by severe ...

  2. 15-Month-Old Infants Fast Map Words but Not Representational Gestures of Multimodal Labels

    PubMed Central

    Puccini, Daniel; Liszkowski, Ulf

    2012-01-01

    This study investigated whether 15-month-old infants fast map multimodal labels, and, when given the choice of two modalities, whether they preferentially fast map one better than the other. Sixty 15-month-old infants watched films where an actress repeatedly and ostensively labeled two novel objects using a spoken word along with a representational gesture. In the test phase, infants were assigned to one of three conditions: Word, Word + Gesture, or Gesture. The objects appeared in a shelf next to the experimenter and, depending on the condition, infants were prompted with either a word, a gesture, or a multimodal word–gesture combination. Using an infant eye tracker, we determined whether infants made the correct mappings. Results revealed that only infants in the Word condition had learned the novel object labels. When the representational gesture was presented alone or when the verbal label was accompanied by a representational gesture, infants did not succeed in making the correct mappings. Results reveal that 15-month-old infants do not benefit from multimodal labeling and that they prefer words over representational gestures as object labels in multimodal utterances. Findings put into question the role of multimodal labeling in early language development. PMID:22493588

  3. [Social pain].

    PubMed

    Shimoyama, Naohito; Shimoyama, Megumi

    2011-09-01

    This chapter focuses on what social pain is and how it should be managed. In order to understand social pain in a cancer patient, it is necessary to recognize the change in the patient's daily life after the diagnosis of cancer. Because the degree of suffering and the relationships with family members and the people he or she worked with differ from patient to patient, it is important to note that the context of social pain is different in each patient. Five points shown below are essential in managing social pain. 1. Economical suffering may be alleviated by utilization of the social security system while taking into account each patient's standard of living. 2. Burdens on family members should be lessened, such as by not having them stay at the patient's bedside every day and letting them go home occasionally. 3. The normal patterns of communication, support, and conflict in the family should be identified, and the extent to which they have been disrupted by the illness should be assessed. 4. It is important to understand the ethnic, cultural, and religious background of the patient and the potential impact of their influence on the individual and the illness. 5. Practical or emotional unfinished business that the patient has needs to be identified, and efforts should be made to support fulfillment.

  4. Breast pain

    PubMed Central

    2007-01-01

    Introduction Breast pain may be cyclical (worse before a period) or non-cyclical, originating from the breast or the chest wall, and occurs at some time in 70% of women. Cyclical breast pain resolves spontaneously in 20-30% of women, but tends to recur in 60% of women. Non-cyclical pain responds poorly to treatment but tends to resolve spontaneously in half of women. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical question: What are the effects of treatments for breast pain? We searched: Medline, Embase, The Cochrane Library and other important databases up to January 2006 (BMJ Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 22 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: a low-fat diet, antibiotics, bromocriptine, danazol, diuretics, evening primrose oil, gestrinone, gonadorelin analogues, hormone replacement therapy, lisuride, progestogens, pyridoxine, tamoxifen, tibolone, topical non-steroidal anti-inflammatory drugs, toremifene, and vitamin E. PMID:19454068

  5. Breast pain

    PubMed Central

    2011-01-01

    Introduction Breast pain may be cyclical (worse before a period) or non-cyclical, originating from the breast or the chest wall, and occurs at some time in 70% of women. Cyclical breast pain resolves spontaneously in 20% to 30% of women, but tends to recur in 60% of women. Non-cyclical pain responds poorly to treatment but tends to resolve spontaneously in half of women. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical question: What are the effects of treatments for breast pain? We searched: Medline, Embase, The Cochrane Library, and other important databases up to May 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 24 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: antibiotics, bromocriptine, combined oral contraceptive pill, danazol, diuretics, evening primrose oil, gestrinone, gonadorelin analogues, hormone replacement therapy (HRT), lisuride, low-fat diet, progestogens, pyridoxine, tamoxifen, tibolone, topical or oral non-steroidal anti-inflammatory drugs (NSAIDs), toremifene, and vitamin E. PMID:21477394

  6. Breast pain

    PubMed Central

    2014-01-01

    Introduction Breast pain may be cyclical (worse before a period) or non-cyclical, originating from the breast or the chest wall, and occurs at some time in 70% of women. Cyclical breast pain resolves spontaneously in 20% to 30% of women, but tends to recur in 60% of women. Non-cyclical pain responds poorly to treatment but tends to resolve spontaneously in half of women. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical question: What are the effects of treatments for breast pain? We searched: Medline, Embase, The Cochrane Library, and other important databases up to February 2014 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 11 studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: bra wearing, combined oral contraceptive pill, danazol, gonadorelin analogues, progestogens, tamoxifen, and topical or oral non-steroidal anti-inflammatory drugs (NSAIDs).

  7. Achilles Pain.

    ERIC Educational Resources Information Center

    Connors, G. Patrick

    Five ailments which can cause pain in the achilles tendon area are: (1) muscular strain, involving the stretching or tearing of muscle or tendon fibers; (2) a contusion, inflammation or infection called tenosynovitis; (3) tendonitis, the inflammation of the tendon; (4) calcaneal bursitis, the inflammation of the bursa between the achilles tendon…

  8. Pain management strategies and lessons from the military: A narrative review

    PubMed Central

    Vallerand, April Hazard; Cosler, Patricia; Henningfield, Jack E; Galassini, Pam

    2015-01-01

    BACKGROUND: Wounded soldiers often experience substantial pain, which must be addressed before returning to active duty or civilian life. The United States (US) military has instituted several guidelines and initiatives aimed at improving pain management by providing rapid access to medical care, and developing interdisciplinary multimodal pain management strategies based on outcomes observed both in combat and hospital settings. OBJECTIVE: To provide a narrative review regarding US military pain management guidelines and initiatives, which may guide improvements in pain management, particularly chronic pain management and prevention, for the general population. METHODS: A literature review of US military pain management guidelines and initiatives was conducted, with a particular focus on the potential of these guidelines to address shortcomings in chronic pain management in the general population. DISCUSSION: The application of US military pain management guidelines has been shown to improve pain monitoring, education and relief. In addition, the US military has instituted the development of programs and guidelines to ensure proper use and discourage aberrant behaviours with regard to opioid use, because opioids are regarded as a critical part of acute and chronic pain management schemes. Inadequate pain management, particularly inadequate chronic pain management, remains a major problem for the general population in the US. Application of military strategies for pain management to the general US population may lead to more effective pain management and improved long-term patient outcomes. PMID:26448972

  9. Painful menstrual periods

    MedlinePlus

    ... related activities for a few days during each menstrual cycle. Painful menstruation is the leading cause of lost ... when did the pain begin? When in your menstrual cycle do you experience the pain? Is the pain ...

  10. Complex Regional Pain Syndrome

    MedlinePlus

    Complex regional pain syndrome (CRPS) is a chronic pain condition. It causes intense pain, usually in the arms, hands, legs, or feet. ... in skin temperature, color, or texture Intense burning pain Extreme skin sensitivity Swelling and stiffness in affected ...

  11. Back Pain During Pregnancy

    MedlinePlus

    ... Management Education & Events Advocacy For Patients About ACOG Back Pain During Pregnancy Home For Patients Search FAQs Back ... Pain During Pregnancy FAQ115, January 2016 PDF Format Back Pain During Pregnancy Pregnancy What causes back pain during ...

  12. When Sex Is Painful

    MedlinePlus

    ... AQ FREQUENTLY ASKED QUESTIONS GYNECOLOGIC PROBLEMS FAQ020 When Sex Is Painful • How common is painful sex? • What causes pain during sex? • Where is pain during sex felt? • When should ...

  13. Fifteen Years of Explaining Pain: The Past, Present, and Future.

    PubMed

    Moseley, G Lorimer; Butler, David S

    2015-09-01

    The pain field has been advocating for some time for the importance of teaching people how to live well with pain. Perhaps some, and maybe even for many, we might again consider the possibility that we can help people live well without pain. Explaining Pain (EP) refers to a range of educational interventions that aim to change one's understanding of the biological processes that are thought to underpin pain as a mechanism to reduce pain itself. It draws on educational psychology, in particular conceptual change strategies, to help patients understand current thought in pain biology. The core objective of the EP approach to treatment is to shift one's conceptualization of pain from that of a marker of tissue damage or disease to that of a marker of the perceived need to protect body tissue. Here, we describe the historical context and beginnings of EP, suggesting that it is a pragmatic application of the biopsychosocial model of pain, but differentiating it from cognitive behavioral therapy and educational components of early multidisciplinary pain management programs. We attempt to address common misconceptions of EP that have emerged over the last 15 years, highlighting that EP is not behavioral or cognitive advice, nor does it deny the potential contribution of peripheral nociceptive signals to pain. We contend that EP is grounded in strong theoretical frameworks, that its targeted effects are biologically plausible, and that available behavioral evidence is supportive. We update available meta-analyses with results of a systematic review of recent contributions to the field and propose future directions by which we might enhance the effects of EP as part of multimodal pain rehabilitation. Perspective: EP is a range of educational interventions. EP is grounded in conceptual change and instructional design theory. It increases knowledge of pain-related biology, decreases catastrophizing, and imparts short-term reductions in pain and disability. It presents the

  14. Understanding pain, part 2: pain management.

    PubMed

    Godfrey, Helen

    This article is the second in a two-part series which explores pain and its management from a physiological perspective. Nurses play an important role in assessing and managing pain. Effective pain management by nurses requires them to have an understanding of the biological basis of the pain interventions which may be used to control pain. This article emphasizes the importance of pain assessment as a precursor for effective pain management and explores the biological basis of pain interventions which contribute to pain control. The role of non-pharmacological approaches in alleviating pain and their actions which contribute to pain relief are explored. The three main types of pharmaceutical agents used, non-opioids, opioids and adjuvant drugs, are introduced and their mechanisms of actions discussed. PMID:16224328

  15. Multimode laser beam analyzer instrument using electrically programmable optics

    NASA Astrophysics Data System (ADS)

    Marraccini, Philip J.; Riza, Nabeel A.

    2011-12-01

    Presented is a novel design of a multimode laser beam analyzer using a digital micromirror device (DMD) and an electronically controlled variable focus lens (ECVFL) that serve as the digital and analog agile optics, respectively. The proposed analyzer is a broadband laser characterization instrument that uses the agile optics to smartly direct light to the required point photodetectors to enable beam measurements of minimum beam waist size, minimum waist location, divergence, and the beam propagation parameter M2. Experimental results successfully demonstrate these measurements for a 500 mW multimode test laser beam with a wavelength of 532 nm. The minimum beam waist, divergence, and M2 experimental results for the test laser are found to be 257.61 μm, 2.103 mrad, 1.600 and 326.67 μm, 2.682 mrad, 2.587 for the vertical and horizontal directions, respectively. These measurements are compared to a traditional scan method and the results of the beam waist are found to be within error tolerance of the demonstrated instrument.

  16. Multimode laser beam analyzer instrument using electrically programmable optics.

    PubMed

    Marraccini, Philip J; Riza, Nabeel A

    2011-12-01

    Presented is a novel design of a multimode laser beam analyzer using a digital micromirror device (DMD) and an electronically controlled variable focus lens (ECVFL) that serve as the digital and analog agile optics, respectively. The proposed analyzer is a broadband laser characterization instrument that uses the agile optics to smartly direct light to the required point photodetectors to enable beam measurements of minimum beam waist size, minimum waist location, divergence, and the beam propagation parameter M(2). Experimental results successfully demonstrate these measurements for a 500 mW multimode test laser beam with a wavelength of 532 nm. The minimum beam waist, divergence, and M(2) experimental results for the test laser are found to be 257.61 μm, 2.103 mrad, 1.600 and 326.67 μm, 2.682 mrad, 2.587 for the vertical and horizontal directions, respectively. These measurements are compared to a traditional scan method and the results of the beam waist are found to be within error tolerance of the demonstrated instrument.

  17. Multimodal imaging measures predict rearrest.

    PubMed

    Steele, Vaughn R; Claus, Eric D; Aharoni, Eyal; Vincent, Gina M; Calhoun, Vince D; Kiehl, Kent A

    2015-01-01

    Rearrest has been predicted by hemodynamic activity in the anterior cingulate cortex (ACC) during error-processing (Aharoni et al., 2013). Here, we evaluate the predictive power after adding an additional imaging modality in a subsample of 45 incarcerated males from Aharoni et al. (2013). Event-related potentials (ERPs) and hemodynamic activity were collected during a Go/NoGo response inhibition task. Neural measures of error-processing were obtained from the ACC and two ERP components, the error-related negativity (ERN/Ne) and the error positivity (Pe). Measures from the Pe and ACC differentiated individuals who were and were not subsequently rearrested. Cox regression, logistic regression, and support vector machine (SVM) neuroprediction models were calculated. Each of these models proved successful in predicting rearrest and SVM provided the strongest results. Multimodal neuroprediction SVM models with out of sample cross-validating accurately predicted rearrest (83.33%). Offenders with increased Pe amplitude and decreased ACC activation, suggesting abnormal error-processing, were at greatest risk of rearrest. PMID:26283947

  18. Multimodality Instrument for Tissue Characterization

    NASA Technical Reports Server (NTRS)

    Mah, Robert W. (Inventor); Andrews, Russell J. (Inventor)

    2000-01-01

    A system with multimodality instrument for tissue identification includes a computer-controlled motor driven heuristic probe with a multisensory tip is discussed. For neurosurgical applications, the instrument is mounted on a stereotactic frame for the probe to penetrate the brain in a precisely controlled fashion. The resistance of the brain tissue being penetrated is continually monitored by a miniaturized strain gauge attached to the probe tip. Other modality sensors may be mounted near the probe tip to provide real-time tissue characterizations and the ability to detect the proximity of blood vessels, thus eliminating errors normally associated with registration of pre-operative scans, tissue swelling, elastic tissue deformation, human judgement, etc., and rendering surgical procedures safer, more accurate, and efficient. A neural network, program adaptively learns the information on resistance and other characteristic features of normal brain tissue during the surgery and provides near real-time modeling. A fuzzy logic interface to the neural network program incorporates expert medical knowledge in the learning process. Identification of abnormal brain tissue is determined by the detection of change and comparison with previously learned models of abnormal brain tissues. The operation of the instrument is controlled through a user friendly graphical interface. Patient data is presented in a 3D stereographics display. Acoustic feedback of selected information may optionally be provided. Upon detection of the close proximity to blood vessels or abnormal brain tissue, the computer-controlled motor immediately stops probe penetration.

  19. Multimodality Imaging of RNA Interference

    PubMed Central

    Nayak, Tapas R.; Krasteva, Lazura K.; Cai, Weibo

    2013-01-01

    The discovery of small interfering RNAs (siRNAs) and their potential to knock down virtually any gene of interest has ushered in a new era of RNA interference (RNAi). Clinical use of RNAi faces severe limitations due to inefficiency delivery of siRNA or short hairpin RNA (shRNA). Many molecular imaging techniques have been adopted in RNAi-related research for evaluation of siRNA/shRNA delivery, biodistribution, pharmacokinetics, and the therapeutic effect. In this review article, we summarize the current status of in vivo imaging of RNAi. The molecular imaging techniques that have been employed include bioluminescence/fluorescence imaging, magnetic resonance imaging/spectroscopy, positron emission tomography, single-photon emission computed tomography, and various combinations of these techniques. Further development of non-invasive imaging strategies for RNAi, not only focusing on the delivery of siRNA/shRNA but also the therapeutic efficacy, is critical for future clinical translation. Rigorous validation will be needed to confirm that biodistribution of the carrier is correlated with that of siRNA/shRNA, since imaging only detects the label (e.g. radioisotopes) but not the gene or carrier themselves. It is also essential to develop multimodality imaging approaches for realizing the full potential of therapeutic RNAi, as no single imaging modality may be sufficient to simultaneously monitor both the gene delivery and silencing effect of RNAi. PMID:23745567

  20. Multimodal imaging measures predict rearrest

    PubMed Central

    Steele, Vaughn R.; Claus, Eric D.; Aharoni, Eyal; Vincent, Gina M.; Calhoun, Vince D.; Kiehl, Kent A.

    2015-01-01

    Rearrest has been predicted by hemodynamic activity in the anterior cingulate cortex (ACC) during error-processing (Aharoni et al., 2013). Here, we evaluate the predictive power after adding an additional imaging modality in a subsample of 45 incarcerated males from Aharoni et al. (2013). Event-related potentials (ERPs) and hemodynamic activity were collected during a Go/NoGo response inhibition task. Neural measures of error-processing were obtained from the ACC and two ERP components, the error-related negativity (ERN/Ne) and the error positivity (Pe). Measures from the Pe and ACC differentiated individuals who were and were not subsequently rearrested. Cox regression, logistic regression, and support vector machine (SVM) neuroprediction models were calculated. Each of these models proved successful in predicting rearrest and SVM provided the strongest results. Multimodal neuroprediction SVM models with out of sample cross-validating accurately predicted rearrest (83.33%). Offenders with increased Pe amplitude and decreased ACC activation, suggesting abnormal error-processing, were at greatest risk of rearrest. PMID:26283947

  1. Multimodality Management of Trigeminal Schwannomas.

    PubMed

    Niranjan, Ajay; Barnett, Samuel; Anand, Vijay; Agazzi, Siviero

    2016-08-01

    Patients presenting with trigeminal schwannomas require multimodality management by a skull base surgical team that can offer expertise in both transcranial and transnasal approaches as well as radiosurgical and microsurgical strategies. Improvement in neurologic symptoms, preservation of cranial nerve function, and control of mass effect are the primary goals of management for trigeminal schwannomas. Complete surgical resection is the treatment of choice but may not be possible in all cases. Radiosurgery is an option as primary management for small- to moderate-sized tumors and can be used for postoperative residuals or recurrences. Planned surgical resection followed by SRS for residual tumor is an effective option for larger trigeminal schwannomas. The endoscopic resection is an excellent approach for patients with an extradural tumor or tumors isolated to the Meckel cave. A detailed analysis of a tumor and its surroundings based on high-quality imaging can help better estimate the expected outcome from each treatment. An expert skull base team should be able to provide precise counseling for each patient's situation for selecting the best option. PMID:27441164

  2. Beam dynamics and wave packet splitting in a periodically curved optical waveguide: multimode effects.

    PubMed

    Marangoni, M; Janner, D; Ramponi, R; Laporta, P; Longhi, S; Cianci, E; Foglietti, V

    2005-08-01

    A theoretical and experimental analysis of beam dynamics and wave packet splitting of light in a periodically bent optical waveguide, a phenomenon recently observed [Phys. Rev. Lett. 94, 073002 (2005)] which is the optical equivalent of adiabatic stabilization of atoms in intense and high-frequency laser fields, is presented in the multimode operational regime. Inhibition of wave packet splitting is theoretically predicted and experimentally observed for higher-order mode excitation.

  3. Shoulder pain

    PubMed Central

    2006-01-01

    Introduction Shoulder pain covers a wide range of problems and affects up to 20% of the population. It is not a specific diagnosis. Shoulder pain can be caused by problems with the acromioclavicular joint, shoulder muscles, or referred pain from the neck. Rotator cuff problems account for 65-70% of cases of shoulder pain. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of oral drug treatment; topical drug treatment; local injections; non-drug treatment; and surgical treatment? We searched: Medline, Embase, The Cochrane Library and other important databases up to February 2006 (BMJ Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 53 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: arthroscopic laser subacromial decompression, corticosteroid injections (intra-articular), corticosteroids (oral, subacromial injection), electrical stimulation, extracorporeal shock wave therapy, guanethidine (intra-articular), ice, laser treatment, manipulation under anaesthesia (plus intra-articular injection in people with frozen shoulder), multidisciplinary biopsychosocial rehabilitation, nerve block, non-steroidal anti-inflammatory drugs (oral, topical or intra-articular injection), opioid analgesics, paracetamol, phonophoresis, physiotherapy (manual treatment, exercises), surgical arthroscopic decompression, transdermal glyceryl trinitrate, ultrasound.

  4. Shoulder pain

    PubMed Central

    2010-01-01

    Introduction Shoulder pain is a common problem with an estimated prevalence of 4% to 26%. About 1% of adults aged over 45 years consult their GP with a new presentation of shoulder pain every year in the UK. The aetiology of shoulder pain is diverse and includes pathology originating from the neck, glenohumeral joint, acromioclavicular joint, rotator cuff, and other soft tissues around the shoulder girdle. The most common source of shoulder pain is the rotator cuff, accounting for over two-thirds of cases. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of oral drug treatment, topical drug treatment, local injections, non-drug treatment, and surgical treatment? We searched: Medline, Embase, The Cochrane Library, and other important databases up to August 2009 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 71 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: acupuncture, arthroscopic subacromial decompression, autologous whole blood injection, corticosteroids (oral, subacromial injection, or intra-articular injection), electrical stimulation, excision of distal clavicle, extracorporeal shock wave therapy, ice, laser treatment, manipulation under anaesthesia, suprascapular nerve block, non-steroidal anti-inflammatory drugs (oral, topical or intra-articular injection), opioid analgesics, paracetamol, physiotherapy (manual treatment, exercises), platelet-rich plasma injection

  5. Pain management following spinal surgeries: An appraisal of the available options

    PubMed Central

    Bajwa, Sukhminder Jit Singh; Haldar, Rudrashish

    2015-01-01

    Spinal procedures are generally associated with intense pain in the postoperative period, especially for the initial few days. Adequate pain management in this period has been seen to correlate well with improved functional outcome, early ambulation, early discharge, and preventing the development of chronic pain. A diverse array of pharmacological options exists for the effective amelioration of post spinal surgery pain. Each of these drugs possesses inherent advantages and disadvantages which restricts their universal applicability. Therefore, combination therapy or multimodal analgesia for proper control of pain appears as the best approach in this regard. The current manuscript discussed the pathophysiology of postsurgical pain including its nature, the various tools for assessment, and the various pharmacological agents (both conventional and upcoming) available at our disposal to respond to post spinal surgery pain. PMID:26288544

  6. [Low back pain during pregnancy. Multidisciplinary approach].

    PubMed

    Gallo-Padilla, D; Gallo-Padilla, C; Gallo-Vallejo, F J; Gallo-Vallejo, J L

    2016-09-01

    After explaining that low back pain is considered the most common pregnancy complication, its pathogenesis, risk factors and the clinical characteristics of the very painful symptoms of this condition are described. As for its approach, it is stressed that it must be multidisciplinary, introducing very important preventive measures, including proper postural hygiene. For its treatment, the methods may be based on non-surgical or pharmacological interventions of a conservative non-invasive nature. Thus, physiotherapy, osteopathic manipulation, multimodal intervention (exercise and education), exercises performed in water environment, acupuncture, etc., have proven to be effective. Finally, it is emphasised that given the significant impact on their quality of life, different health professionals must be proactive and treat the lumbar disease in pregnant women. PMID:26239672

  7. [Low back pain during pregnancy. Multidisciplinary approach].

    PubMed

    Gallo-Padilla, D; Gallo-Padilla, C; Gallo-Vallejo, F J; Gallo-Vallejo, J L

    2016-09-01

    After explaining that low back pain is considered the most common pregnancy complication, its pathogenesis, risk factors and the clinical characteristics of the very painful symptoms of this condition are described. As for its approach, it is stressed that it must be multidisciplinary, introducing very important preventive measures, including proper postural hygiene. For its treatment, the methods may be based on non-surgical or pharmacological interventions of a conservative non-invasive nature. Thus, physiotherapy, osteopathic manipulation, multimodal intervention (exercise and education), exercises performed in water environment, acupuncture, etc., have proven to be effective. Finally, it is emphasised that given the significant impact on their quality of life, different health professionals must be proactive and treat the lumbar disease in pregnant women.

  8. New modalities of pain treatment after outpatient orthopaedic surgery.

    PubMed

    Beaussier, M; Sciard, D; Sautet, A

    2016-02-01

    Postoperative pain relief is one of the cornerstones of success of orthopaedic surgery. Development of new minimally-invasive surgical procedures, as well as improvements in pharmacological and local and regional techniques should result in optimal postoperative pain control for all patients. The analgesic strategy has to be efficient, with minimal side effects, and be easy to manage at home. Multimodal analgesia allows for a reduction of opiate use and thereby its side effects. Local and regional analgesia is a major component of this multimodal strategy, associated with optimal pain relief, even upon mobilization, and it has beneficial effects on postoperative recovery. Ultrasound guidance improves the success rate of distal nerve blocks and makes distal selective blockade possible, helping to preserve the limb's motility. Besides peripheral nerve blocks, local infiltration (incisional and/or intra-articular) is also important to consider. Duration of the nerve blockade is limited after a single injection. This must be taken into consideration to avoid the recurrence of pain when the patient returns home. Continuous perineural blocks using catheters are an option that can be easily managed at home with monitoring by home-care nurses. Extended-release liposomal bupivacaine and adjuvants such as dexamethasone could significantly enhance the duration of the sensory block, thereby reducing the indications for pain pumps. Non-pharmacological approaches, such as cryotherapy, hypnosis and acupuncture should not be ignored. PMID:26803223

  9. Single LP(0,n) mode excitation in multimode fibers.

    PubMed

    Bhatia, Nitin; Rustagi, Kailash C; John, Joseph

    2014-07-14

    We analyze the transmission of a Single mode - Multimode -Multimode (SMm) fiber structure with the aim of exciting a single radial mode in the second multimode fiber. We show that by appropriate choice of the length of the central multimode fiber one can obtain > 90% of the total core power in a chosen mode. We also discuss methods of removing undesirable cladding and radiation modes and estimate tolerances for practical applications.

  10. Radiation characteristics of a multimode linear Zeeman laser

    NASA Astrophysics Data System (ADS)

    Nikonchuk, M. O.; Pugach, I. P.

    An experimental study is presented of a 3.39-micron multimode linear He-Ne Zeeman laser in a longitudinal magnetic field. Conditions are achieved in which elliptically polarized longitudinal modes of the laser are locked by the modulation of resonator losses at the frequency of intermode beats; modulation is carried out using a germanium acoustooptic modulator. An analysis of the laser-emission spectrum is presented, and the frequency and polarization characteristics are investigated. Experimental data on locking and free-lasing regimes are compared, and the observed effects are explained. It is shown that the frequency splitting of modes with opposite signs of ellipticity (achieved by the superposition of a longitudinal magnetic field on the active medium) in the regime of longitudinal-mode locking is realized over the whole gain line of the active medium.

  11. A giant subserosal uterine leiomyoma mimicking an abdominal mass: multimodal imaging data.

    PubMed

    Kalayci, Tugce Ozlem; Akatlı, Ayşe Nur; Sönmezgöz, Fitnet; Türkmen Şamdancı, Emine

    2015-01-01

    Giant uterine leiomyomas are extremely rare neoplasms and are challenging both diagnostically and therapeutically. A 49-year-old premenopausal female presented at our Department complaining of abdominal pain and distention for several years. Ultrasound (US), color Doppler US, abdominal computed tomography imaging after administration of contrast material, and abdominal magnetic resonance imaging were performed. Histopathologic examination revealed a pedunculated subserosal uterine leiomyoma. In this case report, we present abdominopelvic multimodal radiologic imaging findings of our patient with a giant subserosal uterine leiomyoma, in conjunction with histopathological findings.

  12. Multi-mode absorption spectroscopy using a quantum cascade laser for simultaneous detection of NO and H2O

    NASA Astrophysics Data System (ADS)

    O'Hagan, S.; Pinto, T.; Ewart, P.; Ritchie, G. A. D.

    2016-08-01

    Detection of multiple transitions in NO and H2O using multi-mode absorption spectroscopy, MUMAS, with a quantum cascade laser, QCL, operating at 5.3 μm at scan rates up to 10 kHz is reported. The linewidth of longitudinal modes of the QCL is derived from pressure-dependent fits to experimental MUMAS data. Variations in the spectral structure of the broadband, multi-mode, output of the commercially available QCL employed are analysed to provide accurate fits of modelled MUMAS signatures to the experimental data.

  13. Pain and Hand Function.

    PubMed

    Howland, Nicholas; Lopez, Mariela; Zhang, Andrew Y

    2016-02-01

    Pain is a unique somatosensory perception that can dramatically affect our ability to function. It is also a necessary perception, without which we would do irreparable damage to ourselves. In this article, the authors assess the impact of pain on function of the hand. Pain can be categorized into acute pain, chronic pain, and neuropathic pain. Hand function and objective measurements of hand function are analyzed as well as the impact of different types of pain on each of these areas.

  14. Multimodality instrument for tissue characterization

    NASA Technical Reports Server (NTRS)

    Mah, Robert W. (Inventor); Andrews, Russell J. (Inventor)

    2004-01-01

    A system with multimodality instrument for tissue identification includes a computer-controlled motor driven heuristic probe with a multisensory tip. For neurosurgical applications, the instrument is mounted on a stereotactic frame for the probe to penetrate the brain in a precisely controlled fashion. The resistance of the brain tissue being penetrated is continually monitored by a miniaturized strain gauge attached to the probe tip. Other modality sensors may be mounted near the probe tip to provide real-time tissue characterizations and the ability to detect the proximity of blood vessels, thus eliminating errors normally associated with registration of pre-operative scans, tissue swelling, elastic tissue deformation, human judgement, etc., and rendering surgical procedures safer, more accurate, and efficient. A neural network program adaptively learns the information on resistance and other characteristic features of normal brain tissue during the surgery and provides near real-time modeling. A fuzzy logic interface to the neural network program incorporates expert medical knowledge in the learning process. Identification of abnormal brain tissue is determined by the detection of change and comparison with previously learned models of abnormal brain tissues. The operation of the instrument is controlled through a user friendly graphical interface. Patient data is presented in a 3D stereographics display. Acoustic feedback of selected information may optionally be provided. Upon detection of the close proximity to blood vessels or abnormal brain tissue, the computer-controlled motor immediately stops probe penetration. The use of this system will make surgical procedures safer, more accurate, and more efficient. Other applications of this system include the detection, prognosis and treatment of breast cancer, prostate cancer, spinal diseases, and use in general exploratory surgery.

  15. "Filming in Progress": New Spaces for Multimodal Designing

    ERIC Educational Resources Information Center

    Mills, Kathy A.

    2010-01-01

    Global trends call for new research to investigate multimodal designing mediated by new technologies and the implications for classroom spaces. This article addresses the relationship between new technologies, students' multimodal designing, and the social production of classroom spaces. Multimodal semiotics and sociological principles are applied…

  16. Interactions between Pain and the Motor Cortex: Insights from Research on Phantom Limb Pain and Complex Regional Pain Syndrome

    PubMed Central

    Léonard, Guillaume

    2011-01-01

    ABSTRACT Purpose: Pain is a significantly disabling problem that often interacts with other deficits during the rehabilitation process. The aim of this paper is to review evidence of interactions between pain and the motor cortex in order to attempt to answer the following questions: (1) Does acute pain interfere with motor-cortex activity? (2) Does chronic pain interfere with motor-cortex activity, and, conversely, does motor-cortex plasticity contribute to chronic pain? (3) Can the induction of motor plasticity by means of motor-cortex stimulation decrease pain? (4) Can motor training result in both motor-cortex reorganization and pain relief? Summary of Key Points: Acute experimental pain has been clearly shown to exert an inhibitory influence over the motor cortex, which can interfere with motor learning capacities. Current evidence also suggests a relationship between chronic pain and motor-cortex reorganization, but it is still unclear whether one causes the other. However, there is growing evidence that interventions aimed at normalizing motor-cortex organization can lead to pain relief. Conclusions: Interactions between pain and the motor cortex are complex, and more studies are needed to understand these interactions in our patients, as well as to develop optimal rehabilitative strategies. PMID:22654236

  17. Multimode theory of single-photon subtraction

    NASA Astrophysics Data System (ADS)

    Averchenko, V.; Jacquard, C.; Thiel, V.; Fabre, C.; Treps, N.

    2016-08-01

    We develop a general theory to describe the manipulation of a multimode quantum state of light via the subtraction of a single photon. The theory is applicable for various types of subtraction schemes independent of the physical nature of the light modes, their number or the embedded quantum states. We show that different subtraction schemes can be described in a unified approach through the characterization of their intrinsic subtraction modes. The conditional state of the multimode quantum light after the photon subtraction is defined by the number of subtraction modes and their matching with the light modes. We propose the manipulation of light states by controlling the subtraction modes. Performing a photon subtraction on a multimode quantum resource is promising for the implementation of a number of quantum information protocols in all-optical, multiplexed and scalable way.

  18. High Resolution Multimode Fiber Image Recovery

    NASA Technical Reports Server (NTRS)

    Jackson, Deborah

    2000-01-01

    The research emphasis is on developing a cost-effective method of recovering image information from small, closely confined spaces using multimode fibers. The state-of-the-art good quality-viewing fiber, which can currently be used for performing this function, is a 0.5 mm diameter bundle containing 6000 pixels at a cost of $10,000 per fiber bundle. However, these fiber bundles are very fragile and can easily break during surgical use, thereby making instrument reliability and replacement cost,a major impediment to their routine use in many applications. The advantage of working with a single multimode fiber is that it is significantly less expensive and mechanically more robust. In addition, careful choice of numerical aperture allows a higher image resolution (roughly 750,000 pixels) with a 0.5 mm diameter multimode fiber.

  19. Induction of prolonged tenderness in patients with tension-type headache by means of a new experimental model of myofascial pain.

    PubMed

    Mørk, H; Ashina, M; Bendtsen, L; Olesen, J; Jensen, R

    2003-05-01

    Tenderness is the most prominent abnormal finding in patients with tension-type headache (TTH). Recently we developed a model of myofascial tenderness using intramuscular infusion of a combination of bradykinin, serotonin, histamine and prostaglandin E2. We aimed to examine tenderness after this combination in patients with episodic TTH (ETTH). Fifteen patients and 15 healthy controls completed the study. Participants received the combination into the non-dominant trapezius muscle in a randomized, double-blinded and placebo-controlled design. Local tenderness and stimulus-response functions, mechanical pain thresholds (PPDT) in the temporal region and on the finger, and total tenderness score (TTS) were recorded. A local, prolonged, and mild to moderate tenderness was reported both in patients (P = 0.001) and in controls (P = 0.001) after the combination compared with the placebo. The response to the combination tended to be increased in patients. The stimulus-response function was leftward shifted after the combination, compared with baseline in both groups. No changes in PPDT or TTS were found after the infusions, whereas baseline PPDTs were decreased in ETTH compared with controls (PPDTfinger: P = 0.033; PPDTtemporal: P = 0.015). Intramuscular infusion of a combination of endogenous substances induced prolonged tenderness in both patients with episodic TTH and healthy subjects. The present results suggest an increased excitability of peripheral muscle afferents in TTH.

  20. Pain Behavior Changes Following Disc Puncture Relate to Nucleus Pulposus Rather than to the Disc Injury Per Se: An Experimental Study in Rats

    PubMed Central

    Nilsson, Elin; Nakamae, Toshio; Olmarker, Kjell

    2011-01-01

    It has previously been demonstrated that disc puncture in the rat induced changes in grooming and wet dog shakes, two behavioral changes that may be linked to discomfort and neuropathic pain. In this study the aim was to separate the effects of disc injury and the epidural presence of nucleus pulposus. Following anesthesia, the L4-5 disc was exposed using a dorsal approach. Ten rats received a superficial disc injury without nucleus pulposus leakage and ten rats received nucleus pulposus from a donor rat without disc injury. In ten animals the L4-5 disc was punctured using a ventral approach, with 10 corresponding controls. Spontaneous behavior was assessed after surgery. The data was matched to historical control of dorsal sham surgery and disc puncture. The study showed that the effects of nucleus pulposus were more pronounced than the effects induced by the disc injury. Ventral disc puncture did not induce any behavioral changes different from sham exposure. In conclusion, the data from the study indicate that behavioral changes induced by disc puncture are more likely to relate to the epidural presence of nucleus pulposus than the disc injury per se. PMID:21566734

  1. Pain-related and negative semantic priming enhances perceived pain intensity

    PubMed Central

    Richter, Maria; Schroeter, Christoph; Puensch, Theresa; Straube, Thomas; Hecht, Holger; Ritter, Alexander; Miltner, Wolfgang HR; Weiss, Thomas

    2014-01-01

    BACKGROUND: Negative affective and pain-related cues, such as pictures or words, have been shown to act as primes and enhance the perceived intensity of subsequent painful events. For pain-related semantic primes, it remains unclear whether this effect depends on negative valence itself or, specifically, on the pain-relatedness of the words. OBJECTIVES: To investigate the effect of pain-related, negative affective (pain-unrelated) and neutral semantic primes on the perception of subsequent noxious target stimuli. METHODS: Pain ratings in response to noxious electrical stimulation of light and moderate intensity were examined in 39 healthy subjects after subjects were exposed to semantic primes of different meaning and valence (pain-related, negative, positive and neutral adjectives) presented with different interstimulus intervals (0 ms, 500 ms and 1500 ms). RESULTS: Increased pain ratings of noxious stimuli were observed following pain-related and negative compared with neutral primes. DISCUSSION: The results support the motivational priming theory for semantic stimuli, indicating that affectively negative semantic primes increase subjective pain intensity. However, a specific pain-related priming effect was not reliably demonstrated. Additionally, it is shown that experimental parameters (ie, stimulus intensity and interstimulus interval) modify the extent of negative and pain-related semantic priming. CONCLUSIONS: Verbal priming plays a role for the perception of noxious stimuli in a time-dependent manner. PMID:24716197

  2. Placebo analgesia and its opioidergic regulation suggest that empathy for pain is grounded in self pain.

    PubMed

    Rütgen, Markus; Seidel, Eva-Maria; Silani, Giorgia; Riečanský, Igor; Hummer, Allan; Windischberger, Christian; Petrovic, Predrag; Lamm, Claus

    2015-10-13

    Empathy for pain activates brain areas partially overlapping with those underpinning the first-hand experience of pain. It remains unclear, however, whether such shared activations imply that pain empathy engages similar neural functions as first-hand pain experiences. To overcome the limitations of previous neuroimaging research, we pursued a conceptually novel approach: we used the phenomenon of placebo analgesia to experimentally reduce the first-hand experience of pain, and assessed whether this results in a concomitant reduction of empathy for pain. We first carried out a functional MRI experiment (n = 102) that yielded results in the expected direction: participants experiencing placebo analgesia also reported decreased empathy for pain, and this was associated with reduced engagement of anterior insular and midcingulate cortex: that is, areas previously associated with shared activations in pain and empathy for pain. In a second step, we used a psychopharmacological manipulation (n = 50) to determine whether these effects can be blocked via an opioid antagonist. The administration of the opioid antagonist naltrexone blocked placebo analgesia and also resulted in a corresponding "normalization" of empathy for pain. Taken together, these findings suggest that pain empathy may be associated with neural responses and neurotransmitter activity engaged during first-hand pain, and thus might indeed be grounded in our own pain experiences.

  3. Prediction of pain in orthodontic patients based on preoperative pain assessment

    PubMed Central

    Zheng, Baoyu; Ren, Manman; Lin, Feiou; Yao, Linjie

    2016-01-01

    Aim To investigate whether pretreatment assessment of experimental pain can predict the level of pain after archwire placement. Methods One hundred and twenty-one general university students seeking orthodontic treatment were enrolled in this study. A cold pressor test was performed to estimate the pain tolerance of subjects before treatment. Self-reported pain intensity was calculated using a 10 cm visual analog scale during the 7 days after treatment. The relationship between pain tolerance and orthodontic pain was analyzed using Spearman’s correlation analysis. Results The maximum mean level of pain intensity occurred at 24 hours after bonding (53.31±16.13) and fell to normal levels at day 7. Spearman’s correlation analysis found a moderate positive association between preoperative pain tolerance and self-reported pain after archwire placement (P<0.01). There was no significant difference in pain intensity between male and female patients at any time point (P>0.05). Conclusion A simple and noninvasive preoperative sensory test (the cold pressor test) was useful in predicting the risk of developing unbearable pain in patients after archwire placement. Self-reported pain after archwire placement decreased as individual pain tolerance increased. PMID:27042019

  4. Sleep and pain sensitivity in adults.

    PubMed

    Sivertsen, Børge; Lallukka, Tea; Petrie, Keith J; Steingrímsdóttir, Ólöf Anna; Stubhaug, Audun; Nielsen, Christopher Sivert

    2015-08-01

    Sleep problems and pain are major public health concerns, but the nature of the association between the 2 conditions is inadequately studied. The aim of this study was to determine whether a range of sleep measures is associated with experimental increased pain sensitivity. A cross-sectional large population-based study from 2007 to 2008, the Tromsø 6 study, provided data from 10,412 participants (age: mean [SD], 58 [13] years; 54% women). Self-reported sleep measures provided information on sleep duration, sleep onset latency (SOL), and sleep efficiency, as well as frequency and severity of insomnia. The main outcome measure was pain sensitivity tests, including assessment of cold-pressor pain tolerance. We found that all sleep parameters, except sleep duration, were significantly associated with reduced pain tolerance. Both the frequency and severity of insomnia, in addition to SOL and sleep efficiency, were associated with pain sensitivity in a dose-response manner. Adjusting for demographics and psychological distress reduced the strengths of the hazard ratios, but most associations remained significant in the fully adjusted models. There was also a synergistic interaction effect on pain tolerance when combining insomnia and chronic pain. We conclude that sleep problems significantly increase the risk for reduced pain tolerance. Because comorbid sleep problems and pain have been linked to elevated disability, the need to improve sleep among patients with chronic pain, and vice versa, should be an important agenda for future research. PMID:25915149

  5. Pain Part 3: Acute Orofacial Pain.

    PubMed

    Khawaja, Nadine; Renton, Tara

    2015-06-01

    Acute trigeminal pain is a common presentation in the dental surgery, with a reported 22% of the US adult population experiencing orofacial pain more than once during a 6-month period. This article discusses the mechanisms underlying the pain experience, diagnosis and subsequent management of acute trigeminal pain, encompassing pre-, peri- and post-operative analgesia. The dental team spend most of their working lives managing patients and acute pain. The patient may present to the clinician in existing pain, which may often provide a diagnostic challenge. Prevention and managing intra-operative and post-surgical pain are implicit in providing your patient with optimum care. CPD/CLINICAL RELEVANCE: This paper aims to provide an overview of conditions that may present with acute orofacial pain and their management using the most recent evidence base. Intra-operative and post-surgical pain management are also scrutinized and evidence based treatment is recommended.

  6. Pain and the ethics of pain management.

    PubMed

    Edwards, R B

    1984-01-01

    In this article I clarify the concepts of 'pain', 'suffering', 'pains of body', 'pains of soul'. I explore the relevance of an ethic to the clinical setting which gives patients a strong prima facie right to freedom from unnecessary and unwanted pain and which places upon medical professionals two concomitant moral obligations to patients. First, there is the duty not to inflict pain and suffering beyond what is necessary for effective diagnosis, treatment and research. Next, there is the duty to do all that can be done to relieve all the pain and suffering which can be alleviated. I develop in some detail that individuality of pain sensitivity must be taken into account in fulfilling these obligations. I explore the issue of the relevance of informed consent and the right to refuse treatment to the matter of pain relief. And I raise the question of what conditions, if any, should override the right to refuse treatment where pain relief is of paramount concern.

  7. Personality Correlates of Pain Perception and Tolerance.

    ERIC Educational Resources Information Center

    Lukin, Penny R.; Ray, A. Bartow

    1982-01-01

    Explored personality correlates of pain perception and tolerance in a nonmedical sample and setting. Results showed no significant correlations with personality measures and cold-pressor scores, but a significant relationship between pain tolerance and cognitive focus; those who focused on the experimental situation had much shorter tolerance…

  8. Nonlinear processes in multi-mode optical fibers

    NASA Astrophysics Data System (ADS)

    Pourbeyram Kaleibar, Hamed

    Nonlinear processes in optical fibers can affect data transmission and power carried by optical fibers and can limit the bandwidth and the capacity of optical communications. On the other hand nonlinear phenomena could be utilized to build in-fiber all-optical light sources and amplifiers. In this thesis new peaks inside an optical fiber have been generated using nonlinear processes. An intense green pump laser has been launched into a short fiber and specific modes have been excited to generate two new peaks in red and blue wavelengths, where two pump photons are annihilated to create two new photons in red and blue. The generated peaks are shifted far from pump; therefore they are less polluted by pump and Raman induced noises. The phase matching condition and the photon-flux rate for spontaneous and stimulated FWM have been studied both theoretically and experimentally for a commercial grade SMF-28 fiber. In low power and spontaneous regime new peaks are generated from quantum vacuum noise. Using the same pump laser for a long fiber, up to 21 new peaks spanning from green to Infrared have been generated. These peaks are equally spaced by 13THz. Generation of a Raman cascade spanning the wavelength range of 523 to 1750 nm wavelength range, in a standard telecommunication graded-index multimode optical fiber has been reported. Despite the highly multimode nature of the pump, the Raman peaks are generated in specific modes of the fiber, confirming substantial beam cleanup during the stimulated Raman scattering process.

  9. Comprehensive Context Recognizer Based on Multimodal Sensors in a Smartphone

    PubMed Central

    Han, Manhyung; Vinh, La The; Lee, Young-Koo; Lee, Sungyoung

    2012-01-01

    Recent developments in smartphones have increased the processing capabilities and equipped these devices with a number of built-in multimodal sensors, including accelerometers, gyroscopes, GPS interfaces, Wi-Fi access, and proximity sensors. Despite the fact that numerous studies have investigated the development of user-context aware applications using smartphones, these applications are currently only able to recognize simple contexts using a single type of sensor. Therefore, in this work, we introduce a comprehensive approach for context aware applications that utilizes the multimodal sensors in smartphones. The proposed system is not only able to recognize different kinds of contexts with high accuracy, but it is also able to optimize the power consumption since power-hungry sensors can be activated or deactivated at appropriate times. Additionally, the system is able to recognize activities wherever the smartphone is on a human's body, even when the user is using the phone to make a phone call, manipulate applications, play games, or listen to music. Furthermore, we also present a novel feature selection algorithm for the accelerometer classification module. The proposed feature selection algorithm helps select good features and eliminates bad features, thereby improving the overall accuracy of the accelerometer classifier. Experimental results show that the proposed system can classify eight activities with an accuracy of 92.43%.

  10. Low Back Pain

    MedlinePlus

    ... Low Back Pain Overview What is low back pain? Low back pain is a common problem for many people. It can be caused by many ... lift and exercise correctly. Symptoms When is low back pain serious? Call your family doctor if: Pain goes ...

  11. Pain pathways in the primate.

    PubMed

    Willis, W D

    1985-01-01

    From the work reviewed here, it appears that the classical view that there is a sensory channel for pain sensation rather like sensory channels for other sensations seems plausible. However, pain has the property of producing more prominent motivational-affective behaviors than do other sensations (although there are certainly motivational-affective components of the responses to many sensory experiences, such as a verbal attack or the odor of a favorite perfume). It may be that certain nociceptive neurons, such as the STT cells that project to the medial thalamus that have total body receptive fields and many similar spinoreticular neurons, are concerned not so much with sensory events but rather with motivational-affective responses. Nevertheless, there are specific nociceptive afferent fibers, nociceptive spinothalamic tract cells with restricted receptive fields, nociceptive VPL thalamic and SI cortical neurons that presumably could play a crucial role in the sensory-discriminative aspects of pain (signalling, for example, stimulus intensity, location, duration, rate, and quality). Interestingly, many nociceptive neurons receive a convergent input from both sensitive mechanoreceptors and from nociceptors and so can be classified as "wide dynamic range" or multiconvergent neurons. It is not at all clear what the significance is of this kind of multimodal convergence. One possibility is that the weaker tactile input is treated as noise and largely ignored by higher processing centers in the brain. Another possibility is that WDR cells are switched in function by the action of descending pathways originating in the brain stem or cerebral cortex (cf., Gerhart et al., 1984; Yezierski et al., 1983). In any event, the solution of this problem is likely to be very important for the full understanding of the coding properties of nociceptive neurons, and this issue is reminiscent of the coding problem discussed by David Smith in this volume with respect to the gustatory

  12. Acute and Chronic Pain on the Battlefield: Lessons Learned from Point of Injury to the United States.

    PubMed

    Croll, Scott M; Griffith, Scott R

    2016-01-01

    Historically, war tends to accelerate innovation within military medicine. In this article, the authors argue this truism has recurred in the case of acute and chronic pain management for combatants in the global war on terrorism (GWOT). Advances in regional anesthesia techniques and multimodal acute pain care are highlighted in light of the typical weapons, injuries, and comorbid conditions of the modern combat era. Reported success of providing chronic pain care in the war theater during GWOT is discussed in the context of operational requirements for current and future wars. A description is provided of the Pain Management Task Force (PMTF) and Pain Campaign Plan which was initiated during GWOT. The PMTF effort enhanced pain education and clinical pain care through leadership and organizational changes, which created broader access to pain treatments for patients and more standardized treatment capabilities across the enterprise. PMID:27215875

  13. Aspects of multimode quantum optomechanics

    NASA Astrophysics Data System (ADS)

    Seok, HyoJun

    This dissertation aims to investigate systems in which several optical and mechanical degrees of freedom are coupled through optomechanical interactions. Multimode optomechanics creates the prospect of integrated functional devices and it allows us to explore new types of optomechanical interactions which account for collective dynamics and optically mediated mechanical interactions. Owing to the development of fabrication techniques for micro- and nano-sized mechanical elements, macroscopic mechanical oscillators can be cooled to the deep quantum regime via optomechanical interaction. Based on the possibility to control the motion of mechanical oscillators at the quantum level, we design several schemes involving mechanical systems of macroscopic length and mass scales and we explore the nonlinear dynamics of mechanical oscillators. The first scheme includes a quantum cantilever coupled to a classical tuning fork via magnetic dipole-dipole interaction and also coupled to a single optical field mode via optomechanical interaction. We investigate the generation of nonclassical squeezed states in the quantum cantilever and their detection by transferring them to the optical field. The second scheme involves a quantum membrane coupled to two optical modes via optomechanical interaction. We explore dynamic stabilization of an unstable position of a quantum mechanical oscillator via modulation of the optical fields. We then develop a general formalism to fully describe cavity mediated mechanical interactions. We explore a rather general configuration in which multiple mechanical oscillators interact with a single cavity field mode. We specifically consider the situation in which the cavity dissipation is the dominant source of damping so that the cavity field follows the dynamics of the mechanical modes. In particular, we study two limiting regimes with specific applications: the weak-coupling regime and single-photon strong-coupling regime. In the weak-coupling regime

  14. Altered brain activity during pain processing in fibromyalgia.

    PubMed

    Burgmer, Markus; Pogatzki-Zahn, Esther; Gaubitz, Markus; Wessoleck, Erik; Heuft, Gereon; Pfleiderer, Bettina

    2009-01-15

    Fibromyalgia syndrome (FMS) is characterized by widespread pain. Studies with functional neuroimaging support the hypothesis of central pain augmentation in FMS. We tested this in our study with a novel paradigm of tonic pain induced by a single stimulus. Tonic pain, in contrast to phasic pain, seems to be a more appropriate experimental approach to study adaptive mechanisms of pain processing in FMS. We hypothesized that brain areas related to the "medial" pain system and the amygdalae will present different activation in patients compared to healthy subjects. An fMRI-block design before, during and after an incision was made in patients with FMS and in healthy controls. Acute pain caused by the incision was measured during the course of the experiment. A 2 factorial model of BOLD-signal changes was designed to explore significant differences of brain activation between both groups during the pain stimulus. Additionally the first Eigenvariates in those areas which show an interaction between both factors were determined over the time course of pain stimulation. Differences of activation in the fronto-cingulate cortex, the supplemental motor areas, and the thalamus were found between both groups with distinct differences in BOLD-signals changes over the time course of pain stimulation, even during anticipation of pain. Our results support the hypothesis that central mechanisms of pain processing in the medial pain system, favourable cognitive/affective factors even during the anticipation of pain, may play an important role for pain processing in patients with FMS. PMID:18848998

  15. Multimode interferometer for guided matter waves.

    PubMed

    Andersson, Erika; Calarco, Tommaso; Folman, Ron; Andersson, Mauritz; Hessmo, Björn; Schmiedmayer, Jörg

    2002-03-11

    Atoms can be trapped and guided with electromagnetic fields, using nanofabricated structures. We describe the fundamental features of an interferometer for guided matter waves, built of two combined Y-shaped beam splitters. We find that such a device is expected to exhibit high contrast fringes even in a multimode regime, analogous to a white light interferometer.

  16. The Arts, New Literacies, and Multimodality

    ERIC Educational Resources Information Center

    Albers, Peggy; Harste, Jerome C.

    2007-01-01

    The arts, multimodality, and new literacies studies, each with its own distinct principles, together can redefine literacy and what constitutes being literate. To recognize the roles that each of these fields plays in literacy necessitates a cultural shift in reading, interpreting, creating, and responding to a range of multimedia messages. The…

  17. Experiential Influences on Multimodal Perception of Emotion

    ERIC Educational Resources Information Center

    Shackman, Jessica E.; Pollak, Seth D.

    2005-01-01

    The impact of 2 types of learning experiences on children's perception of multimodal emotion cues was examined. Children (aged 7-12 years) were presented with conflicting facial and vocal emotions. The effects of familiarity were tested by varying whether emotions were presented by familiar or unfamiliar adults. The salience of particular…

  18. Multimodal Student Interaction Online: An Ecological Perspective

    ERIC Educational Resources Information Center

    Berglund, Therese Ornberg

    2009-01-01

    This article describes the influence of tool and task design on student interaction in language learning at a distance. Interaction in a multimodal desktop video conferencing environment, FlashMeeting, is analyzed from an ecological perspective with two main foci: participation rates and conversational feedback strategies. The quantitative…

  19. A Multimodal Perspective on Textuality and Contexts

    ERIC Educational Resources Information Center

    Jewitt, Carey

    2007-01-01

    Textuality is often thought of in linguistic terms; for instance, the talk and writing that circulate in the classroom. In this paper I take a multimodal perspective on textuality and context. I draw on illustrative examples from school Science and English to examine how image, colour, gesture, gaze, posture and movement--as well as writing and…

  20. Researching Multimodal Texts: Applying a Dynamic Model.

    ERIC Educational Resources Information Center

    Clancy, Susan; Lowrie, Tom

    The arrival of the digital age requires new approaches to understand the literacies used in making meanings from multimodal communications, and a rethinking of the ways in which research into these areas can be used to support learners in the 21st century. This presentation examines the range of literacies children have developed and used to make…