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1

Pain threshold and tolerance in Alzheimer's disease  

Microsoft Academic Search

We tested both pain thresholds and pain tolerance in patients with Alzheimer's disease (AD) by means of phasic and tonic noxious stimuli. In the first case, electrical stimulation was used, whereas in the second case arm ischemia was studied. By comparing AD patients with normal subjects of the same age, we found no differences in stimulus detection and pain thresholds,

Fabrizio Benedetti; Sergio Vighetti; Claudia Ricco; Elisabetta Lagna; Bruno Bergamasco; Lorenzo Pinessi; Innocenzo Rainero

1999-01-01

2

The relationship of experimental pain tolerance to pain threshold  

Microsoft Academic Search

This study examined the effects resulting from an application of the more permissive instructions of Clark and Bindra to the technique of Gelfand et al., and compared the findings to those of Gelfand. The hypotheses tested were: no significant difference between groups for pain threshold; pain tolerance is significantly lower when instructions are more permissive; regardless of instructions, the correlation

Sidney Gelfand

1964-01-01

3

Gender role expectations of pain is associated with pain tolerance limit but not with pain threshold  

Microsoft Academic Search

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

Ruth Defrin; Libby Shramm; Ilana Eli

2009-01-01

4

Thresholds and tolerance of physical pain among young adults who self-injure  

PubMed Central

Prevalence rates of nonsuicidal self-injury among college students range from 17% to 38%. Research indicates that individuals with borderline personality disorder who self-injure sometimes report an absence of pain during self-injury. Furthermore, self-injury in the absence of pain has been associated with more frequent suicide attempts. The present study examined pain thresholds and tolerance among 44 college students (11 who engaged in self-injury and 33 who did not). Pain thresholds and tolerance were measured using an algometer pressure device that was used to produce pain in previous laboratory research. Participants who engaged in self-injury had a higher pain tolerance than those who did not. In addition, participants who engaged in self-injury rated the pain as less intense than participants who did not. ANCOVAs revealed that depression was associated with pain rating and pain tolerance.

McCoy, Katrina; Fremouw, William; McNeil, Daniel W

2010-01-01

5

Alone but Feeling No Pain: Effects of Social Exclusion on Physical Pain Tolerance and Pain Threshold, Affective Forecasting, and Interpersonal Empathy  

Microsoft Academic Search

Prior findings of emotional numbness (rather than distress) among socially excluded persons led the authors to investigate whether exclusion causes a far-reaching insensitivity to both physical and emotional pain. Experiments 1–4 showed that receiving an ostensibly diagnostic forecast of a lonesome future life reduced sensitivity to physical pain, as indicated by both (higher) thresholds and tolerance. Exclusion also caused emotional

C. Nathan DeWall; Roy F. Baumeister

2006-01-01

6

Lateral Dominance, Pain Perception, and Pain Tolerance  

Microsoft Academic Search

It has been suggested that lateral dominance influences pain perception and pain tolerance ; but when electric stimulation was used on human teeth, there appeared to be no difference in the pain perception threshold values on each side of the midline. Pain tolerance values seem to support the suggestion, but the results were not statistically significant.

A. V. Newton; J. M. Mumford

1972-01-01

7

Use of pain threshold reports to satisfy social needs  

PubMed Central

OBJECTIVE: To examine the hypothesis that experimental threats to social belongingness, interacting with individual differences in attachment security, cause modification of pain threshold reports by individuals who report high pain thresholds at baseline. METHODS: In each of three studies, baseline pain threshold and tolerance were assessed in response to a pain task (cold pressor pain in Studies 1 and 2, finger pressure pain in Study 3). Participants then completed a measure of attachment security and were randomly assigned to a social exclusion or control condition (exclusion from a computer game in Study 1, recalling past rejection experiences in Studies 2 and 3). The pain task was administered again to examine the effects on pain threshold and tolerance. RESULTS: Those with high anxious attachment and high baseline pain thresholds reported higher postmanipulation pain thresholds in the exclusion conditions than in the control conditions. Those with low anxious attachment and high baseline pain thresholds reported lower postmanipulation pain thresholds in the exclusion conditions than in the control conditions. No differences were found for pain tolerance. CONCLUSIONS: Across studies, results suggested that postmanipulation pain threshold reports of individuals with high baseline pain thresholds were particularly responsive to social exclusion. The form of the response was dependent on the level of anxious attachment. The present studies provide evidence that variance in pain threshold reports not accounted for by pain intensity may reflect the use of pain reports to satisfy social needs. This work also suggests that baseline measures of pain thresholds may, in interaction with psychological variables, have predictive power beyond serving as a control variable.

MacDonald, Geoff

2008-01-01

8

Effects of suggestion on d' and Cx for pain detection and pain tolerance  

Microsoft Academic Search

Results of a study with 20 male and 20 female college students demonstrated that suggestion directed toward eliciting fewer reports of detection of minimal pain and suggestion directed toward greater pain tolerance (fewer withdrawals) altered the response probabilities in the expected direction and in addition raised both the pain detection and pain tolerance thresholds to thermal stimulation. However, sensory decision

W. Crawford Clark; Janet S. Goodman

1974-01-01

9

The relationship of experimental pain tolearance to pain threshold: A critique of Gelfand's paper  

Microsoft Academic Search

Recently, this Journal published a paper by S. Gelfand discussing the relationship of experimental pain tolerance to pain threshold. His paper is of considerable interest as it raises three important issues for the experimental study of pain. This critique is written both to emphasize these three problems in view of their general significance and also to discuss certain controversial statements

B. Berthold Wolff

1964-01-01

10

Tactile threshold and pressure pain threshold during treatment of orofacial pain: an explorative study  

Microsoft Academic Search

The aim of the present study was to evaluate the pressure pain threshold (PPT), tactile threshold (TT) and pain intensity as measured on a Visual Analogue Scale (VAS) in patients with pain in the orofacial region. Twenty-six patients with myogenous pain (7 ss), myogenous and capsular pain (11 ss) or neuropathic pain (8 ss) participated in the study. At baseline,

Wojciech Drobek; Antoon De Laat; Joseph Schoenaers

2001-01-01

11

Assessment of pressure-pain thresholds and central sensitization of pain in lateral epicondylalgia.  

PubMed

OBJECTIVE.: To assess pain sensitivity and spreading hyperalgesia in lateral epicondylalgia (LE). SUBJECTS.: Twenty-two women with LE, and 38 controls were included. OUTCOME MEASURES.: Computerized cuff pressure algometry was used for assessment of pressure-pain threshold and tolerance. The stimulus was applied using a single (stimulation-area: 241?cm(2) ) or double-chambered (stimulation-area: 482?cm(2) ) tourniquet on the arm and leg. Spatial summation was expressed as the ratio between pressure-pain thresholds to single and double cuff-chamber stimulation. During 10-minute constant pressure stimulation at intensity relative to the individual pain threshold, the pain intensity was continuously recorded using an electronic visual analogue scale (VAS), and from this the degree of temporal summation was estimated. For LE, a Doppler ultrasound examination of the elbow was made to identify inflammation. RESULTS.: In LE compared with controls the pressure-pain threshold and tolerance were on average reduced by respectively 31% (nonsignificant) and 18% (nonsignificant) on the lower arm and by 32% (P?pain thresholds were on average reduced by 20% (P?pain tolerance by 10% (nonsignificant) on the painful compared with the asymptomatic side. Spatial summation (P?pain hypersensitivity and Doppler ultrasound into clinically meaningful subgroups with varying duration of symptoms and different degrees of central sensitization. These groups may require different pain management strategies. PMID:23279601

Jespersen, Anders; Amris, Kirstine; Graven-Nielsen, Thomas; Arendt-Nielsen, Lars; Bartels, Else Marie; Torp-Pedersen, Søren; Bliddal, Henning; Danneskiold-Samsoe, Bente

2012-12-28

12

Social laughter is correlated with an elevated pain threshold.  

PubMed

Although laughter forms an important part of human non-verbal communication, it has received rather less attention than it deserves in both the experimental and the observational literatures. Relaxed social (Duchenne) laughter is associated with feelings of wellbeing and heightened affect, a proximate explanation for which might be the release of endorphins. We tested this hypothesis in a series of six experimental studies in both the laboratory (watching videos) and naturalistic contexts (watching stage performances), using change in pain threshold as an assay for endorphin release. The results show that pain thresholds are significantly higher after laughter than in the control condition. This pain-tolerance effect is due to laughter itself and not simply due to a change in positive affect. We suggest that laughter, through an endorphin-mediated opiate effect, may play a crucial role in social bonding. PMID:21920973

Dunbar, R I M; Baron, Rebecca; Frangou, Anna; Pearce, Eiluned; van Leeuwen, Edwin J C; Stow, Julie; Partridge, Giselle; MacDonald, Ian; Barra, Vincent; van Vugt, Mark

2011-09-14

13

Social laughter is correlated with an elevated pain threshold  

PubMed Central

Although laughter forms an important part of human non-verbal communication, it has received rather less attention than it deserves in both the experimental and the observational literatures. Relaxed social (Duchenne) laughter is associated with feelings of wellbeing and heightened affect, a proximate explanation for which might be the release of endorphins. We tested this hypothesis in a series of six experimental studies in both the laboratory (watching videos) and naturalistic contexts (watching stage performances), using change in pain threshold as an assay for endorphin release. The results show that pain thresholds are significantly higher after laughter than in the control condition. This pain-tolerance effect is due to laughter itself and not simply due to a change in positive affect. We suggest that laughter, through an endorphin-mediated opiate effect, may play a crucial role in social bonding.

Dunbar, R. I. M.; Baron, Rebecca; Frangou, Anna; Pearce, Eiluned; van Leeuwen, Edwin J. C.; Stow, Julie; Partridge, Giselle; MacDonald, Ian; Barra, Vincent; van Vugt, Mark

2012-01-01

14

Pain tolerance in upper limb disorders: findings from a community survey  

PubMed Central

Aims: To test the hypothesis that non-specific upper limb pain arises from altered pain perception with reduced tolerance of sensory stimuli. Methods: Subjects undergoing clinical examination as part of a community based survey of upper limb disorders were invited to return for an assessment of pain tolerance. A standardised algorithm was used to classify the 94 participants according to whether they had specific upper limb disorders (n = 22), non-specific arm pain (n = 15), or no arm pain (n = 57). Pain tolerance was assessed at three anatomical sites in each arm in response to electrocutaneous stimulation with alternating currents up to a maximum of 10 mA at three frequencies (5, 250, and 2000 Hz). A proportional odds model was used to compare pain tolerance thresholds according to sex, age, and diagnosis. Results: Women were less tolerant of pain than men (OR 0.13) and tolerance also declined with age (OR for one year increase in age 0.97). After allowance for sex and age, there was no indication that pain tolerance was lower in subjects with non-specific arm pain than in those with specific upper limb disorders or those who had no arm pain. Conclusions: The study hypothesis was not supported. However, before the hypothesis is dismissed, it should be tested further in patients with more severe and disabling arm pain.

Mitchell, S; Reading, I; Walker-Bone, K; Palmer, K; Cooper, C; Coggon, D

2003-01-01

15

THE EFFECTS OF SLEEP DEPRIVATION AND SLEEP RECOVERY ON PAIN THRESHOLDS OF RATS WITH CHRONIC PAIN  

Microsoft Academic Search

Background and objective: The aim of this study was to compare the effects of different paradoxical sleep deprivation methods on the pain threshold in rats submitted to inflammatory and neuropathic pain models. We also investigated whether changes in pain threshold could be reverted by sleep recovery period. Methods: Wistar rats were randomly assigned in arthritis-induced by adjuvant (AIA), chronic constrictive

Monica Levy Andersen; Regiane Kawakami; Sergio Tufik

16

Sleep Deprivation Affects Thermal Pain Thresholds but Not Somatosensory Thresholds in Healthy Volunteers  

Microsoft Academic Search

Objective: Sleep disturbances have been thought to augment pain. Sleep deprivation has been proven to produce hyperalgesic effects. It is still unclear whether these changes are truly specific to pain and not related to general changes in somatosensory functions. The aim of the present study was to evaluate the effect of total sleep deprivation on thermal pain thresholds (heat, cold)

BERND KUNDERMANN; JULIA SPERNAL; MARTIN TOBIAS HUBER; JURGEN-CHRISTIAN KRIEG; STEFAN LAUTENBACHER

2004-01-01

17

Cutaneous thermal thresholds in patients with painful burning feet.  

PubMed Central

Small nerve fibre sensory function was assessed by psychophysical estimates of cutaneous thermal thresholds in 30 patients who presented with the symptoms of painful burning feet. Thresholds were abnormal in 12 and normal in 18 patients although symptoms in the two groups were very similar. Various hypotheses for the mechanism of pain in small fibre neuropathy have been proposed previously and these are discussed, but the cause of symptoms in patients with normal thresholds, is unknown. The possibility exists that these patients have a neuropathic disorder which affects only those unmyelinated fibres involved with pain.

Smith, S J; Ali, Z; Fowler, C J

1991-01-01

18

Fear and anxiety: divergent effects on human pain thresholds  

Microsoft Academic Search

Animal studies suggest that fear inhibits pain whereas anxiety enhances it; however it is unclear whether these effects generalize to humans. The present study examined the effects of experimentally induced fear and anxiety on radiant heat pain thresholds. Sixty male and female human subjects were randomly assigned to 1 of 3 emotion induction conditions: (1) fear, induced by exposure to

Jamie L Rhudy; Mary W Meagher

2000-01-01

19

Dopamine transporter genotype dependent effects of apomorphine on cold pain tolerance in healthy volunteers.  

PubMed

The aims of this study were to assess the effects of the dopamine agonist apomorphine on experimental pain models in healthy subjects and to explore the possible association between these effects and a common polymorphism within the dopamine transporter gene. Healthy volunteers (n?=?105) participated in this randomized double-blind, placebo-controlled, cross-over trial. Heat pain threshold and intensity, cold pain threshold, and the response to tonic cold pain (latency, intensity, and tolerance) were evaluated before and for up to 120 min after the administration of 1.5 mg apomorphine/placebo. A polymorphism (3'-UTR 40-bp VNTR) within the dopamine transporter gene (SLC6A3) was investigated. Apomorphine had an effect only on tolerance to cold pain, which consisted of an initial decrease and a subsequent increase in tolerance. An association was found between the enhancing effect of apomorphine on pain tolerance (120 min after its administration) and the DAT-1 polymorphism. Subjects with two copies of the 10-allele demonstrated significantly greater tolerance prolongation than the 9-allele homozygote carriers and the heterozygote carriers (p?=?0.007 and p?=?0.003 in comparison to the placebo, respectively). In conclusion, apomorphine administration produced a decrease followed by a genetically associated increase in cold pain tolerance. PMID:23704939

Treister, Roi; Pud, Dorit; Ebstein, Richard P; Eisenberg, Elon

2013-05-21

20

Dopamine Transporter Genotype Dependent Effects of Apomorphine on Cold Pain Tolerance in Healthy Volunteers  

PubMed Central

The aims of this study were to assess the effects of the dopamine agonist apomorphine on experimental pain models in healthy subjects and to explore the possible association between these effects and a common polymorphism within the dopamine transporter gene. Healthy volunteers (n?=?105) participated in this randomized double-blind, placebo-controlled, cross-over trial. Heat pain threshold and intensity, cold pain threshold, and the response to tonic cold pain (latency, intensity, and tolerance) were evaluated before and for up to 120 min after the administration of 1.5 mg apomorphine/placebo. A polymorphism (3?-UTR 40-bp VNTR) within the dopamine transporter gene (SLC6A3) was investigated. Apomorphine had an effect only on tolerance to cold pain, which consisted of an initial decrease and a subsequent increase in tolerance. An association was found between the enhancing effect of apomorphine on pain tolerance (120 min after its administration) and the DAT-1 polymorphism. Subjects with two copies of the 10-allele demonstrated significantly greater tolerance prolongation than the 9-allele homozygote carriers and the heterozygote carriers (p?=?0.007 and p?=?0.003 in comparison to the placebo, respectively). In conclusion, apomorphine administration produced a decrease followed by a genetically associated increase in cold pain tolerance.

Treister, Roi; Pud, Dorit; Ebstein, Richard P.; Eisenberg, Elon

2013-01-01

21

Lower threshold for adenosine-induced chest pain in patients with angina and normal coronary angiograms  

PubMed Central

Objective—To investigate whether patients with angina-like chest pain and normal coronary angiograms are more sensitive to adenosine as an inducer of chest pain. Design—Increasing doses of adenosine were given in a single blind study as intravenous bolus injections. Chest pain and the electrocardio?raphic findings were noted. Patients—Eight patients with anginalike chest pain but no coronary stenoses (group A), nine patients with angina and coronary stenoses (group B), and 16 healthy volunteers (group C). Results—In the absence of ischaemic signs on the electrocardiogram adenosine provoked angina-like pain in all patients in groups A and B. The pain was located in the chest, and its quality and location were described as being no different from the patient's habitual angina. In group C, 14 of 16 subjects reported chest pain. The lowest dose resulting in chest pain was lower in group A (0·9 (0·6) mg) than in group B (3·1 (1·5) mg) (p < 0·005) and in group C (6·2 (3·7) mg) (p < 0·005). The maximum tolerable dose was lower in group A (4·7 (2·1) mg) than in group B (9·2 (3·8) mg) (p < 0·05) and in group C (12·0 (4·1) mg) (p < 0·005). Conclusions—Patients with anginalike chest pain and normal coronary angiograms have a low pain threshold and low tolerance to pain induced by adenosine.

Lagerqvist, Bo; Sylven, Christer; Waldenstrom, Anders

1992-01-01

22

Dynorphin Promotes Abnormal Pain and Spinal Opioid Antinociceptive Tolerance  

Microsoft Academic Search

The nonopioid actions of spinal dynorphin may promote aspects of abnormal pain after nerve injury. Mechanistic similarities have been suggested between opioid tolerance and neuropathic pain. Here, the hypothesis that spinal dynorphin might mediate effects of sustained spinal opioids was explored. Possible abnormal pain and spinal antinociceptive tolerance were evaluated after intrathecal administration of (D-Ala 2, N-Me-Phe 4, Gly-ol 5)enke

Todd W. Vanderah; Luis R. Gardell; Shannon E. Burgess; Mohab Ibrahim; Ahmet Dogrul; Cheng-Min Zhong; En-Tan Zhang; T. Philip; Michael H. Ossipov; Josephine Lai; Frank Porreca

2000-01-01

23

Effect of manipulated state aggression on pain tolerance.  

PubMed

Swearing produces a pain lessening (hypoalgesic) effect for many people; an emotional response may be the underlying mechanism. In this paper, the role of manipulated state aggression on pain tolerance and pain perception is assessed. In a repeated-measures design, pain outcomes were assessed in participants asked to play for 10 minutes a first-person shooter video game vs a golf video game. Sex differences were explored. After playing the first-person shooter video game, aggressive cognitions, aggressive affect, heart rate, and cold pressor latency were increased, and pain perception was decreased. These data indicate that people become more pain tolerant with raised state aggression and support our theory that raised pain tolerance from swearing occurs via an emotional response. PMID:23045874

Stephens, Richard; Allsop, Claire

2012-08-01

24

Change in pain threshold by meperidine, naproxen sodium, and acetaminophen as determined by electric pulp testing.  

PubMed Central

The purpose of this study was to compare changes in pain threshold caused by meperidine, naproxen sodium, acetaminophen, and placebo. The change in pain threshold was measured by electric pulp testing. Acetaminophen elevated the pain threshold statistically significantly. Clinically, however, the superiority of acetaminophen is questionable. No elevation of the pain threshold occurred with narcotic drugs or with nonsteroidal anti-inflammatory drugs: our research shows that the electric pulp tests of patients who have taken these drugs preoperatively will have results similar to those of patients who have taken no drugs. We question the philosophy of administering these drugs for change in pain threshold at the levels used here preoperatively.

Carnes, P. L.; Cook, B.; Eleazer, P. D.; Scheetz, J. P.

1998-01-01

25

Handling Ibuprofen Increases Pain Tolerance and Decreases Perceived Pain Intensity in a Cold Pressor Test  

PubMed Central

Pain contributes to health care costs, missed work and school, and lower quality of life. Extant research on psychological interventions for pain has focused primarily on developing skills that individuals can apply to manage their pain. Rather than examining internal factors that influence pain tolerance (e.g., pain management skills), the current work examines factors external to an individual that can increase pain tolerance. Specifically, the current study examined the nonconscious influence of exposure to meaningful objects on the perception of pain. Participants (N?=?54) completed a cold pressor test, examined either ibuprofen or a control object, then completed another cold pressor test. In the second test, participants who previously examined ibuprofen reported experiencing less intense pain and tolerated immersion longer (relative to baseline) than those who examined the control object. Theoretical and applied implications of these findings are discussed.

Rutchick, Abraham M.; Slepian, Michael L.

2013-01-01

26

Pain Tolerance, Arousal, and Personality Relationships of Athletes and Nonathletes  

ERIC Educational Resources Information Center

In this study, college athletes and nonathletes performed a muscular endurance task to determine pain tolerance, during which galvanic skin-response measures of arousal were obtained. The Bernreuter Personality Inventory was administered after this treatment. (JS)

Ellison, Kerry; Freischlag, Jerry

1975-01-01

27

Effects of ramp time on sensory, motor and tolerance thresholds during exogenous electrical stimulation.  

PubMed

This investigation examined the effects of ramp time on the current intensity needed to elicit sensory, motor and pain tolerance response. Forty-seven healthy subjects were randomly divided into three groups. Subjects in group one (no. 17), group two (no. 15), and group three (no. 15) had the onset (ramp time) knob present at 1.0, 3.5 and 5.0 seconds, respectively. Subsequently, the wrist and finger flexors of the dominant hand were stimulated following standardized instructions. For each subject, the current intensity needed to elicit: (1) the sensory response, (2) minimum perceptible contraction, and (3) the maximum tolerance level of painful stimulation was determined. Significant F ratio was found for the current intensity at different perceptual level (p less than 0.5) but not for ramp time (p greater than .05). The findings suggest that with the stimulator used in this study, ramp time has no effect on the three basic excitatory responses, i.e., thresholds of sensory, motor and painful stimulation. PMID:1806728

Balogun, J A

1991-12-01

28

Rowers' high: behavioural synchrony is correlated with elevated pain thresholds.  

PubMed

Physical exercise is known to stimulate the release of endorphins, creating a mild sense of euphoria that has rewarding properties. Using pain tolerance (a conventional non-invasive assay for endorphin release), we show that synchronized training in a college rowing crew creates a heightened endorphin surge compared with a similar training regime carried out alone. This heightened effect from synchronized activity may explain the sense of euphoria experienced during other social activities (such as laughter, music-making and dancing) that are involved in social bonding in humans and possibly other vertebrates. PMID:19755532

Cohen, Emma E A; Ejsmond-Frey, Robin; Knight, Nicola; Dunbar, R I M

2009-09-15

29

Rowers' high: behavioural synchrony is correlated with elevated pain thresholds  

PubMed Central

Physical exercise is known to stimulate the release of endorphins, creating a mild sense of euphoria that has rewarding properties. Using pain tolerance (a conventional non-invasive assay for endorphin release), we show that synchronized training in a college rowing crew creates a heightened endorphin surge compared with a similar training regime carried out alone. This heightened effect from synchronized activity may explain the sense of euphoria experienced during other social activities (such as laughter, music-making and dancing) that are involved in social bonding in humans and possibly other vertebrates.

Cohen, Emma E. A.; Ejsmond-Frey, Robin; Knight, Nicola; Dunbar, R. I. M.

2010-01-01

30

Testing different biphasic waveforms and capacitances: Effect on atrial defibrillation threshold and pain perception  

Microsoft Academic Search

Objectives. The goal of this study was to compare the effect of different tilts and capacitances for biphasic shocks on atrial defibrillation efficacy and pain threshold.Background. Although biphasic shocks have been shown to be superior to monophasic shocks, the effect of tilt and capacitance on atrial defibrillation success and pain perception has not been studied in patients.Methods. Atrial defibrillation threshold

Gery Tomassoni; Keith H. Newby; Margaret M. Kearney; Mary Joan Brandon; Helen Barold; Andrea Natale

1996-01-01

31

Effects of Sensory Behavioral Tasks on Pain Threshold and Cortical Excitability  

PubMed Central

Background/Objective Transcutaneous electrical stimulation has been proven to modulate nervous system activity, leading to changes in pain perception, via the peripheral sensory system, in a bottom up approach. We tested whether different sensory behavioral tasks induce significant effects in pain processing and whether these changes correlate with cortical plasticity. Methodology/Principal Findings This randomized parallel designed experiment included forty healthy right-handed males. Three different somatosensory tasks, including learning tasks with and without visual feedback and simple somatosensory input, were tested on pressure pain threshold and motor cortex excitability using transcranial magnetic stimulation (TMS). Sensory tasks induced hand-specific pain modulation effects. They increased pain thresholds of the left hand (which was the target to the sensory tasks) and decreased them in the right hand. TMS showed that somatosensory input decreased cortical excitability, as indexed by reduced MEP amplitudes and increased SICI. Although somatosensory tasks similarly altered pain thresholds and cortical excitability, there was no significant correlation between these variables and only the visual feedback task showed significant somatosensory learning. Conclusions/Significance Lack of correlation between cortical excitability and pain thresholds and lack of differential effects across tasks, but significant changes in pain thresholds suggest that analgesic effects of somatosensory tasks are not primarily associated with motor cortical neural mechanisms, thus, suggesting that subcortical neural circuits and/or spinal cord are involved with the observed effects. Identifying the neural mechanisms of somatosensory stimulation on pain may open novel possibilities for combining different targeted therapies for pain control.

Volz, Magdalena Sarah; Pinheiro, Fernando Santos; Merabet, Lotfi B.; Fregni, Felipe

2013-01-01

32

A Phase II, Randomized, Double-Blind, Placebo Controlled, Dose-Response Trial of the Melatonin Effect on the Pain Threshold of Healthy Subjects  

PubMed Central

Background Previous studies have suggested that melatonin may produce antinociception through peripheral and central mechanisms. Based on the preliminary encouraging results of studies of the effects of melatonin on pain modulation, the important question has been raised of whether there is a dose relationship in humans of melatonin on pain modulation. Objective The objective was to evaluate the analgesic dose response of the effects of melatonin on pressure and heat pain threshold and tolerance and the sedative effects. Methods Sixty-one healthy subjects aged 19 to 47 y were randomized into one of four groups: placebo, 0.05 mg/kg sublingual melatonin, 0.15 mg/kg sublingual melatonin or 0.25 mg/kg sublingual melatonin. We determine the pressure pain threshold (PPT) and the pressure pain tolerance (PPTo). Quantitative sensory testing (QST) was used to measure the heat pain threshold (HPT) and the heat pain tolerance (HPTo). Sedation was assessed with a visual analogue scale and bispectral analysis. Results Serum plasma melatonin levels were directly proportional to the melatonin doses given to each subject. We observed a significant effect associated with dose group. Post hoc analysis indicated significant differences between the placebo vs. the intermediate (0.15 mg/kg) and the highest (0.25 mg/kg) melatonin doses for all pain threshold and sedation level tests. A linear regression model indicated a significant association between the serum melatonin concentrations and changes in pain threshold and pain tolerance (R2?=?0.492 for HPT, R2?=?0.538 for PPT, R2?=?0.558 for HPTo and R2?=?0.584 for PPTo). Conclusions The present data indicate that sublingual melatonin exerts well-defined dose-dependent antinociceptive activity. There is a correlation between the plasma melatonin drug concentration and acute changes in the pain threshold. These results provide additional support for the investigation of melatonin as an analgesic agent. Brazilian Clinical Trials Registry (ReBec): (U1111-1123-5109). IRB: Research Ethics Committee at the Hospital de Clínicas de Porto Alegre.

Stefani, Luciana Cadore; Muller, Suzana; Torres, Iraci L. S.; Razzolini, Bruna; Rozisky, Joanna R.; Fregni, Felipe; Markus, Regina; Caumo, Wolnei

2013-01-01

33

Physiological responses and tolerance threshold to cadmium contamination in Eremochloa ophiuroides  

Microsoft Academic Search

Plant tolerance is one of the preconditions in soil phytoremediation. The physiological responses and tolerance threshold of centipedegrass (Eremochloa ophiuroides) were investigated under eight different Cd concentrations (0, 60, 120, 180, 240, 300, 360 and 420 mg Cd kg) in a sand culture system. The results showed that turf quality, leaf relative water content (RWC), leaf electrolyte leakage (EL), leaf

Yiming Liu; Kai Wang; Peixian Xu; Zhaolong Wang

2011-01-01

34

Performance of music elevates pain threshold and positive affect: implications for the evolutionary function of music.  

PubMed

It is well known that music arouses emotional responses. In addition, it has long been thought to play an important role in creating a sense of community, especially in small scale societies. One mechanism by which it might do this is through the endorphin system, and there is evidence to support this claim. Using pain threshold as an assay for CNS endorphin release, we ask whether it is the auditory perception of music that triggers this effect or the active performance of music. We show that singing, dancing and drumming all trigger endorphin release (indexed by an increase in post-activity pain tolerance) in contexts where merely listening to music and low energy musical activities do not. We also confirm that music performance results in elevated positive (but not negative) affect. We conclude that it is the active performance of music that generates the endorphin high, not the music itself. We discuss the implications of this in the context of community bonding mechanisms that commonly involve dance and music-making. PMID:23089077

Dunbar, R I M; Kaskatis, Kostas; MacDonald, Ian; Barra, Vinnie

2012-10-22

35

Pain perception in competitive swimmers.  

PubMed Central

The pain perception of 30 competitive swimmers was studied using experimentally induced ischaemic pain. The pain thresholds and tolerances of this group were compared with those of 30 club swimmers and 26 non-competitive athletes. While pain thresholds showed little difference between the groups, pain tolerances were considerably different. Pain tolerances of the competitive swimmers varied according to the stage of the training season. The relation between ischaemic pain and that experienced during swimming training was studied using a pain questionnaire composed of several systematically structured verbal categories. Both types of pain were classified along similar dimensions, and it was concluded that the experimentally demonstrated pain tolerances could be generalized to the normal pain perception of the subjects. The origins of the enhanced pain tolerances of the competitive swimmers would seem to lie in their systematic exposure to brief periods of intense pain. These data could have relevance for the treatment of chronic pain in certain diseases.

Scott, V; Gijsbers, K

1981-01-01

36

Reduced heat pain thresholds after sad-mood induction are associated with changes in thalamic activity.  

PubMed

Negative affective states influence pain processing in healthy subjects in terms of augmented pain experience. Furthermore, our previous studies revealed that patients with major depressive disorder showed increased heat pain thresholds on the skin. Potential neurofunctional correlates of this finding were located within the fronto-thalamic network. The aim of the present study was to investigate the neurofunctional underpinnings of the influence of sad mood upon heat pain processing in healthy subjects. For this purpose, we used a combination of the Velten Mood Induction procedure and a piece of music to induce sad affect. Initially we assessed heat pain threshold after successful induction of sad mood outside the MR scanner in Experiment 1. We found a highly significant reduction in heat pain threshold on the left hand and a trend for the right. In Experiment 2, we applied thermal pain stimuli on the left hand (37, 42, and 45 degrees C) in an MRI scanner. Subjects were scanned twice, one group before and after sad-mood induction and another group before and after neutral-mood induction, respectively. Our main finding was a significant group x mood-induction interaction bilaterally in the ventrolateral nucleus of the thalamus indicating a BOLD signal increase after sad-mood induction and a BOLD signal decrease in the control group. We present evidence that induced sad affect leads to reduced heat pain thresholds in healthy subjects. This is probably due to altered lateral thalamic activity, which is potentially associated with changed attentional processes. PMID:19027763

Wagner, Gerd; Koschke, Mandy; Leuf, Tanja; Schlösser, Ralf; Bär, Karl-Jürgen

2008-11-05

37

Determinants of pressure pain threshold in adult twins: evidence that shared environmental influences predominate  

Microsoft Academic Search

The objective of this study was to examine the relative contribution of genetic and environmental factors in determining pain perception in a classical twin study. Dolorimeter measurements of pressure pain threshold (PPT) were recorded in 609 healthy female-female twin pairs of whom 269 pairs were monozygotic (MZ) and 340 were dizygotic (DZ). There was a strong correlation (R) in PPT

Alexander J. MacGregor; Gareth O. Griffiths; Juliet Baker; Timothy D. Spector

1997-01-01

38

Pressure pain thresholds of tender point sites in patients with fibromyalgia and in healthy controls  

Microsoft Academic Search

Pressure pain threshold (PPT) is defined as the minimum force applied which induces pain. This measure has proven to be commonly useful in evaluating tenderness symptom. Our aim was to study the intra-examiner reproducibility of PPT measurement, define cutoffs in normal groups, and compare these results with patients with fibromyalgia (FM). Fifty healthy females, 50 healthy males, and 20 patients

Didier Maquet; Jean-Louis Croisier; Christophe Demoulin; Jean-Michel Crielaard

2004-01-01

39

Transcutaneous electrical nerve stimulation produces variable changes in somatosensory evoked potentials, sensory perception and pain threshold: clinical implications for pain relief.  

PubMed Central

Transcutaneous electrical nerve stimulation decreased early and late somatosensory evoked potential amplitudes and stimulus intensity ratings, and elevated sensory detection threshold, in normal subjects. Effects on pain threshold depended on pre-treatment threshold. These findings are relevant to treatment of clinical pain by transcutaneous electrical nerve stimulation.

Golding, J F; Ashton, H; Marsh, R; Thompson, J W

1986-01-01

40

Lubiprostone does not Influence Visceral Pain Thresholds in Patients with Irritable Bowel Syndrome  

PubMed Central

Background In clinical trials, lubiprostone reduced the severity of abdominal pain. Aims The primary aim was to determine whether lubiprostone raises the threshold for abdominal pain induced by intraluminal balloon distention. A secondary aim was to determine whether changes in pain sensitivity influence clinical pain independently of changes in transit time. Methods Sixty-two patients with irritable bowel syndrome with constipation (IBS-C) participated in an 8-week crossover study. All subjects completed a 14-day baseline ending with a barostat test of pain and urge sensory thresholds. Half, randomly selected, then received 48 ug/day of lubiprostone for 14 days ending with a pain sensitivity test and a Sitzmark test of transit time. This was followed by a 14-day washout and then a crossover to 14 days of placebo with tests of pain sensitivity and transit time. The other half of the subjects received placebo before lubiprostone. All kept symptom diaries. Results Stools were significantly softer when taking lubiprostone compared to placebo (Bristol Stool scores 4.20 vs. 3.44, p<0.001). However, thresholds for pain (17.36 vs. 17.83 mmHg, lubiprostone vs. placebo) and urgency to defecate (14.14 vs. 14.53 mmHg) were not affected by lubiprostone. Transit time was not significantly different between lubiprostone and placebo (51.27 vs. 51.81 hours), and neither pain sensitivity nor transit time was a significant predictor of clinical pain. Conclusions Lubiprostone has no effect on visceral sensory thresholds. The reductions in clinical pain that occur while taking lubiprostone appear to be secondary to changes in stool consistency.

Whitehead, William E.; Palsson, Olafur S.; Gangarosa, Lisa; Turner, Marsha; Tucker, Jane

2011-01-01

41

The Fine Tuning of Pain Thresholds: A Sophisticated Double Alarm System  

PubMed Central

Two distinctive features characterize the way in which sensations including pain, are evoked by heat: (1) a thermal stimulus is always progressive; (2) a painful stimulus activates two different types of nociceptors, connected to peripheral afferent fibers with medium and slow conduction velocities, namely A?- and C-fibers. In the light of a recent study in the rat, our objective was to develop an experimental paradigm in humans, based on the joint analysis of the stimulus and the response of the subject, to measure the thermal thresholds and latencies of pain elicited by A?- and C-fibers. For comparison, the same approach was applied to the sensation of warmth elicited by thermoreceptors. A CO2 laser beam raised the temperature of the skin filmed by an infrared camera. The subject stopped the beam when he/she perceived pain. The thermal images were analyzed to provide four variables: true thresholds and latencies of pain triggered by heat via A?- and C-fibers. The psychophysical threshold of pain triggered by A?-fibers was always higher (2.5–3°C) than that triggered by C-fibers. The initial skin temperature did not influence these thresholds. The mean conduction velocities of the corresponding fibers were 13 and 0.8 m/s, respectively. The triggering of pain either by C- or by A?-fibers was piloted by several factors including the low/high rate of stimulation, the low/high base temperature of the skin, the short/long peripheral nerve path and some pharmacological manipulations (e.g. Capsaicin). Warming a large skin area increased the pain thresholds. Considering the warmth detection gave a different picture: the threshold was strongly influenced by the initial skin temperature and the subjects detected an average variation of 2.7°C, whatever the initial temperature. This is the first time that thresholds and latencies for pain elicited by both A?- and C-fibers from a given body region have been measured in the same experimental run. Such an approach illustrates the role of nociception as a “double level” and “double release” alarm system based on level detectors. By contrast, warmth detection was found to be based on difference detectors. It is hypothesized that pain results from a CNS build-up process resulting from population coding and strongly influenced by the background temperatures surrounding at large the stimulation site. We propose an alternative solution to the conventional methods that only measure a single “threshold of pain”, without knowing which of the two systems is involved.

Plaghki, Leon; Decruynaere, Celine; Van Dooren, Paul; Le Bars, Daniel

2010-01-01

42

Pain tolerance in patients presenting to primary care and physiotherapy services with upper limb disorders  

Microsoft Academic Search

Background: Arm pain is a common cause of incapacity for work and is often attributed to occupational activities, but in many cases the pathogenesis is unclear.Objective: To investigate whether arm pain in the absence of identifiable underlying pathology is associated with reduced tolerance of painful sensory stimuli.Methods: 133 incident cases of arm pain, recruited from primary care and physiotherapy services,

Claire Ryall; David Coggon; Robert Peveler; Isabel Reading; Keith T Palmer

2007-01-01

43

Altered esophageal pain threshold in irritable bowel syndrome  

Microsoft Academic Search

Gut motility disorders and altered pain perception were reported in patients with irritable bowel syndrome (IBS). To verify foregut involvement in IBS, we studied 30 patients using esophageal manometry and 24-hr pH monitoring of the distal esophagus. Two subgroups of patients underwent esophageal provocative tests (bethanechol 50 µg\\/kg subcutaneously and esophageal balloon distension test). Twelve healthy volunteers formed a control

Mario Costantini; Giacomo Carlo Sturniolo; Giovanni Zaninotto; Renata D'Incà; Rita Polo; Remo Naccarato; Ermanno Ancona

1993-01-01

44

Threshold of tolerability: the impact of management changes to recreational fishing in Ningaloo Marine Park  

Microsoft Academic Search

Purpose – The purpose of this paper is to examine a model for conceptualizing the impacts of environmental management strategies on travel and recreation choice making behavior that considers tolerance thresholds in visitor responses to destination change. Design\\/methodology\\/approach – A survey involving a sample of 347 regular campers and fishers in the Ningaloo Marine Park, Australia, is analyzed to discern

Jeremy Northcote; Jim Macbeth

2008-01-01

45

Changes in tooth pulpal detection and pain thresholds in relation to jaw movement in man  

Microsoft Academic Search

The effect of jaw movements on pulpal sensory thresholds to electrical stimulation was studied in healthy humans. The movements consisted of repeated jaw opening and closing at two different frequencies (1 and 3 s?1). The detection\\/perception and pain thresholds of an upper or lower central incisor were determined by stimulation with monopolar constant current pulses at two different durations (0.5

P Kemppainen; I Vaalamo; N Leppälä; A Pertovaara

2001-01-01

46

Changes in sensory hand representation and pain thresholds induced by motor cortex stimulation in humans.  

PubMed

Shrinking of deafferented somatosensory regions after neural damage is thought to participate to the emergence of neuropathic pain, and pain-relieving procedures have been reported to induce the normalization of altered cortical maps. While repetitive magnetic stimulation (rTMS) of the motor cortex can lessen neuropathic pain, no evidence has been provided that this is concomitant to changes in sensory maps. Here, we assessed in healthy volunteers the ability of 2 modes of motor cortex rTMS commonly used in pain patients to induce changes in pain thresholds and plastic phenomena in the S1 cortex. Twenty minutes of high-frequency (20 Hz) rTMS significantly increased pain thresholds in the contralateral hand, and this was associated with the expansion of the cortical representation of the hand on high-density electroencephalogram source analysis. Neither of these effects were observed after sham rTMS, nor following intermittent theta-burst stimulation (iTBS). The superiority of 20-Hz rTMS over iTBS to induce sensory plasticity may reflect its better match with intrinsic cortical motor frequencies, which oscillate at around 20 Hz. rTMS-induced changes might partly counterbalance the plasticity induced by a nerve lesion, and thus substantiate the use of rTMS to treat human pain. However, a mechanistic relation between S1 plasticity and pain-relieving effects is far from being established. PMID:22918979

Houzé, Bérengère; Bradley, Claire; Magnin, Michel; Garcia-Larrea, Luis

2012-08-23

47

Randomized controlled pilot study: pain intensity and pressure pain thresholds in patients with neck and low back pain before and after traditional East Asian "gua sha" therapy.  

PubMed

Gua Sha is a traditional East Asian healing technique where the body surface is "press-stroked" with a smooth-edged instrument to raise therapeutic petechiae that last 2-5 days. The technique is traditionally used in the treatment of both acute and chronic neck and back pain. This study aimed to measure the effects of Gua Sha therapy on the pain ratings and pressure pain thresholds of patients with chronic neck pain (CNP) and chronic low back pain (CLBP). A total of 40 patients with either CNP or CLBP (mean age 49.23 ± 10.96 years) were randomized to either a treatment group (TG) or a waiting list control group (WLC). At baseline assessment (T1), all patients rated their pain on a 10 cm visual analog scale (VAS). Patients' pressure pain thresholds (PPT) at a site of maximal pain (pain-maximum) and an adjacent (pain-adjacent) site were also established. The treatment group then received a single Gua Sha treatment. Post-intervention measurements were taken for both groups at T2, seven days after baseline assessment (T1), using the same VAS and PPT measurements in precisely the same locations as at T1. Final analysis were conducted with 21 patients with CNP and 18 patients with CLBP. The study groups were equally distributed with regard to randomization. Patients in both the CNP and the CLBP treatment groups reported pain reduction (p < 0.05) and improved health status from their one Gua Sha treatment, as compared to the waiting list group. Pain sensitivity improved in the TG in CNP, but not in CLBP patients, possibly due to higher pressure sensitivity in the neck area. No adverse events were reported. These results suggest that Gua Sha may be an effective treatment for patients with chronic neck and low back pain. Further study of Gua Sha is warranted. PMID:22928824

Lauche, Romy; Wübbeling, Klaus; Lüdtke, Rainer; Cramer, Holger; Choi, Kyung-Eun; Rampp, Thomas; Michalsen, Andreas; Langhorst, Jost; Dobos, Gustav J

2012-01-01

48

Relationships between pain thresholds, catastrophizing and gender in acute whiplash injury.  

PubMed

The mechanisms underlying sensory hypersensitivity (SH) in acute whiplash associated disorders (WAD) are not well understood. We examined the extent of the relationships between the sensory measures of pressure pain threshold (PPT) and cold pain threshold (CPT), catastrophizing, pain and disability levels and gender in acute WAD. Thirty-seven subjects reporting neck pain following a motor vehicle accident were examined within five weeks post-injury. Measures of neck pain and disability (Neck Disability Index, NDI) and catastrophizing (Pain Catastrophizing Scale, PCS) were taken. CPT was assessed in the cervical spine and PPTs were assessed in the cervical spine (PPTcx) and at a remote site (PPTdistal). CPT and PCS were moderately correlated (r=0.46; p < 0.01); however there were no significant relationships between PPT (cervical and distal) and PCS. Both CPT (r=0.55, p < 0.01) and PPTcx (r=-0.42, p < 0.01) were significantly correlated with NDI but PPTdistal was not (r=-0.08, p=0.65). Finally, gender modulated the relationships between sensory measures, catastrophizing, and pain and disability levels. In conclusion, subjects with higher levels of catastrophizing presented with sensory hypersensitivity to cold stimuli in the acute phase of whiplash. Differences between genders are in accordance with the growing body of evidence suggesting that the relationships between some psychological factors and injury-related symptoms are modulated by gender. PMID:19892580

Rivest, Karine; Côté, Julie N; Dumas, Jean-Pierre; Sterling, Michele; De Serres, Sophie J

2009-11-05

49

Gender role expectations of pain: relationship to experimental pain perception  

Microsoft Academic Search

The primary purpose of this study was to investigate the influence of an individual's Gender Role Expectations of Pain (GREP) on experimental pain report. One hundred and forty-eight subjects (87 females and 61 males) subjects underwent thermal testing and were asked to report pain threshold, pain tolerance, VAS ratings of pain intensity and unpleasantness, and a computerized visual analogue scales

Emily A Wise; Donald D Price; Cynthia D Myers; Marc W Heft; Michael E Robinson

2002-01-01

50

Test–retest reliability of the nociceptive withdrawal reflex and electrical pain thresholds after single and repeated stimulation in patients with chronic low back pain  

Microsoft Academic Search

Recent studies have shown that the nociceptive withdrawal reflex threshold (NWR-T) and the electrical pain threshold (EP-T)\\u000a are reliable measures in pain-free populations. However, it is necessary to investigate the reliability of these measures\\u000a in patients with chronic pain in order to translate these techniques from laboratory to clinic. The aims of this study were\\u000a to determine the test–retest reliability

José A. Biurrun Manresa; Alban Y. Neziri; Michele Curatolo; Lars Arendt-Nielsen; Ole K. Andersen

2011-01-01

51

Is Paradoxical Pain Induced by Sustained Opioid Exposure an Underlying Mechanism of Opioid Antinociceptive Tolerance?  

Microsoft Academic Search

Opiates are the primary treatment for pain management in cancer patients reporting moderate to severe pain, and are being increasingly used for non-cancer chronic pain. However, prolonged administration of opiates is associated with significant problems including the development of antinociceptive tolerance, wherein higher doses of the drug are required over time to elicit the same amount of analgesia. High doses

Tamara King; Michael H. Ossipov; Todd W. Vanderah; Frank Porreca; Josephine Lai

2005-01-01

52

Early chimerism threshold predicts sustained engraftment and NK-cell tolerance in prenatal allogeneic chimeras  

PubMed Central

The failure of engraftment in human cases of in utero hematopoietic cell transplantation (IUHCT) in which no immunodeficiency exists suggests the presence of an unrecognized fetal immune barrier. A similar barrier in murine IUHCT appears to be dependent on the chimerism level and is poorly explained by a lack of T-cell tolerance induction. Therefore, we studied the effect of the chimerism level on engraftment and host natural killer (NK)–cell education in a murine model of IUHCT. The dose of transplanted cells was found to exhibit a strong correlation with both the engraftment rate and chimerism level. More specifically, a threshold level of initial chimerism (> 1.8%) was identified that predicted durable engraftment for allogeneic IUHCT, whereas low initial chimerism (< 1.8%) predicted a loss of engraftment. NK cells taken from chimeras above the “chimerism threshold” displayed durable calibration of alloresponsive Ly49A receptors and tolerance to donor antigens. Depletion of recipient NK cells stabilized engraftment in low-level chimeras (< 1.8%). These studies illustrate the importance of the early chimerism threshold in predicting long-term engraftment and host NK-cell tolerance after in utero transplantation.

Durkin, Emily T.; Jones, Kelly A.; Rajesh, Deepika

2008-01-01

53

Changes to cold detection and pain thresholds following low and high frequency transcranial magnetic stimulation of the motor cortex  

Microsoft Academic Search

There is some evidence that repetitive transcranial magnetic stimulation (rTMS) can alleviate the experience of chronic pain. The mechanisms by which rTMS may induce pain relief, however, are unknown. The present study examined whether a session of rTMS would produce sensory threshold changes in healthy individuals. Detection and pain thresholds for cold sensations were compared following low frequency (1Hz) (Experiment

Jeff Summers; Sama Johnson; Saxby Pridmore; Gajinder Oberoi

2004-01-01

54

The role of experiential avoidance in acute pain tolerance: a laboratory test.  

PubMed

The present investigation examined the role of experiential avoidance in terms of acute pain tolerance and subsequent recovery. Seventy nonclinical participants completed the Acceptance and Action Questionnaire and underwent a well-established cold pressor task. Results indicated that individuals reporting higher levels of experiential avoidance had lower pain endurance and tolerance and recovered more slowly from this particular type of aversive event. Consistent with theoretical prediction, these findings suggest that experiential avoidance may play a role in tolerance of acute pain. PMID:15882839

Feldner, Matthew T; Hekmat, Hamid; Zvolensky, Michael J; Vowles, Kevin E; Secrist, Zachary; Leen-Feldner, Ellen W

2006-06-01

55

Lagged association between geomagnetic activity and diminished nocturnal pain thresholds in mice.  

PubMed

A wide variety of behaviors in several species has been statistically associated with the natural variations in geomagnetism. To examine whether changes in geomagnetic activity are associated with pain thresholds, adult mice were exposed to a hotplate paradigm once weekly for 52 weeks during the dark cycle. Planetary A index values from the previous 6 days of a given hotplate session were correlated with the mean response latency for subjects to the thermal stimulus. We found that hotplate latency was significantly (P < 0.05) and inversely correlated (rho = -0.25) with the daily geomagnetic intensity 3 days prior to testing. Therefore, if the geomagnetic activity was greater 3 days before a given hotplate trial, subjects tended to exhibit shorter response latencies, suggesting lower pain thresholds or less analgesia. These results are supported by related experimental findings and suggest that natural variations in geomagnetic intensity may influence nociceptive behaviors in mice. PMID:17657732

Galic, M A; Persinger, M A

2007-10-01

56

Effect of transcutaneous electrical nerve stimulation on sensation thresholds in patients with painful diabetic neuropathy: an observational study.  

PubMed

Transcutaneous electrical nerve stimulation (TENS) is one of the therapies for painful neuropathy. Its analgesic mechanisms probably involve the gate control theory, the physiological block and the endogenous pain inhibitory system. The aim of the study was to determine whether TENS improves small fibre function diminished because of painful diabetic neuropathy. Forty-six patients with painful diabetic neuropathy were treated with TENS three consecutive hours a day for 3 weeks. Treatment effect was evaluated with cold, warm, cold pain and heat pain thresholds, vibration perception thresholds and touch perception thresholds. In all patients, thermal-specific and thermal pain sensitivity determination showed quantitative and qualitative abnormalities in all the measured spots. After the TENS therapy, no statistically significant changes in cold, warm, cold pain, heat pain, vibratory perception and touch perception thresholds were observed in the stimulated area. TENS did not alter C, A? nor A? fibre-mediated perception thresholds. The observed changes at thenar are probably because of central mechanisms. In general, analgesic mechanisms of TENS are likely to be complex. PMID:20042866

Mohari?, Metka; Burger, Helena

2010-09-01

57

Overhead and noise threshold of fault-tolerant quantum error correction  

NASA Astrophysics Data System (ADS)

Fault-tolerant quantum error correction (QEC) networks are studied by a combination of numerical and approximate analytical treatments. The probability of failure of the recovery operation is calculated for a variety of Calderbank-Shor-Steane codes, including large block codes and concatenated codes. Recent insights into the syndrome extraction process, which render the whole process more efficient and more noise tolerant, are incorporated. The average number of recoveries that can be completed without failure is thus estimated as a function of various parameters. The main parameters are the gate ? and memory ? failure rates, the physical scale-up of the computer size, and the time tm required for measurements and classical processing. The achievable computation size is given as a surface in parameter space. This indicates the noise threshold as well as other information. It is found that concatenated codes based on the [[23,1,7

Steane, Andrew M.

2003-10-01

58

Fentanyl Buccal Tablet for Relief of Breakthrough Pain in Opioid-Tolerant Patients With Cancer-Related Chronic Pain  

Microsoft Academic Search

Fentanyl buccal tablet (FBT) is a new opioid formulation pro- viding rapid-onset analgesia for the treatment of breakthrough pain (BTP). This study evaluated FBT for BTP in opioid-tolerant patients with chronic cancer pain. The study had a randomized, double-blind, placebo- controlled design and was conducted at 30 outpatient treatment centers in the United States. Following open-label titration, patients were ran-

Neal E. Slatkin; Fang Xie; John Messina; Thalia J. Segal

2007-01-01

59

Comparison of exercise tolerance and chest pain during exercise stress testing in three different ethnic groups  

Microsoft Academic Search

Background: Exercise tolerance and exertional chest pain are important prognostic tools for assessing patients with suspected or known ischemic heart disease. The purpose of this study was to evaluate whether exercise time and exertional chest pain differ between African Americans (AA), Caucasians (C) and Hispanics (H).Methods: We evaluated 507 patients who underwent exercise stress testing using standard Bruce protocol with

O. J Rodriguez; V. N Iyer; M Lue; K. T Hickey; D. K Blood; S. R Bergmann; S Bokhari

2004-01-01

60

Knee Extensor Strength Is Associated with Pressure Pain Thresholds in Adults with Fibromyalgia  

PubMed Central

Objective Individuals with fibromyalgia (FM) have lower muscle strength and lower pressure pain thresholds (PPT). The primary aim of this study was to determine the associations between muscle strength and PPT in adults with FM to test the hypothesis that greater measures of muscle strength would be associated with greater values of PPT. Secondary aims included determining the effects of pain severity and the peak uptake of oxygen (Vo2) on the associations between muscle strength and PPT. Methods Knee extensor and flexor strength (N?=?69) was measured in the dominant leg using a dynamometer, and PPT was assessed using an electronic algometer. Pain severity was determined using the Multidimensional Pain Inventory, and peak Vo2 uptake was quantified using an electronically braked cycle ergometer. Results Univariable linear regression analysis demonstrated a significant association between PPT (dependent variable) and isometric knee extensor (P<.001), isokinetic (60°/s) knee extensor (P?=?.002), and isokinetic (60°/s) knee flexor strength (P?=?.043). In a multiple variable linear regression analysis adjusted for age, sex, pain severity, body mass index and peak Vo2 uptake, a significant association was found between PPT and isometric knee extensor strength (P?=?.008). In a similar multiple variable analysis, a significant association was found between PPT and isokinetic knee extensor strength (P?=?.044). Conclusion Greater measures of isometric and isokinetic knee extensor strength were significantly associated with greater values of PPT in both univariable and multiple variable linear regression models. Trial Registration ClinicalTrials.gov NCT01253395

Hooten, W. Michael; Rosenberg, Casandra J.; Eldrige, Jason S.; Qu, Wenchun

2013-01-01

61

The initial effects of a Mulligan's mobilization with movement technique on range of movement and pressure pain threshold in pain-limited shoulders  

Microsoft Academic Search

There is little known about the specific manual therapy techniques used to treat painfully limited shoulders and their effects on range of movement (ROM) and pressure pain threshold (PPT). The objective of this study was to investigate the initial effects of a Mulligan's mobilization with movement (MWM) technique on shoulder ROM in the plane of the scapula and PPT in

Pamela Teys; Leanne Bisset; Bill Vicenzino

2008-01-01

62

Factor analysis of human pain responses: Pain endurance as a specific pain factor  

Microsoft Academic Search

Induced cutaneous and deep somatic pain with chemical, electrical, and thermal noxious stimuli in 60 18-69 yr. Old chronic arthritis patients. Pain threshold, pain tolerance, and pain sensitivity range (psr) were measured psychophysically and correlated within and between techniques. The correlations were subjected to the centroid method of factor analysis and the 1st 4 factors extracted and rotated to a

B. Berthold Wolff

1971-01-01

63

Fentanyl buccal tablet for relief of breakthrough pain in opioid-tolerant patients with cancer-related chronic pain.  

PubMed

Fentanyl buccal tablet (FBT) is a new opioid formulation providing rapid-onset analgesia for the treatment of breakthrough pain (BTP). This study evaluated FBT for BTP in opioid-tolerant patients with chronic cancer pain. The study had a randomized, double-blind, placebo-controlled design and was conducted at 30 outpatient treatment centers in the United States. Following open-label titration, patients were randomly assigned to 1 of 18 double-blind dose sequences (7 FBT tablets, 3 placebo) to treat 10 BTP episodes. Pain intensity was measured on an 11-point scale (0 = no pain; 10 = worst pain). The primary efficacy measure was the sum of pain intensity differences (PIDs) for the first 60 minutes (SPID60); secondary efficacy measures included PIDs and pain relief (PR) measured from 5 minutes through 2 hours. Adverse events (AEs) were recorded. Of 129 patients enrolled, 87 entered the double-blind phase. SPID60 significantly favored FBT versus placebo (mean +/- SE, 9.7 +/- 0.63 vs 4.9 +/- 0.50; P < 0.0001). Secondary measures also favored FBT: PIDs and PR showed significant differences versus placebo at 10 minutes (0.9 vs 0.5; 0.815 vs 0.606, respectively, P < 0.0001) and all subsequent time points (P < 0.0001). AEs were typical of opioids (eg, nausea, dizziness, fatigue). In conclusion, in this study of opioid-tolerant patients with chronic cancer pain and BTP, FBT was efficacious, well tolerated, demonstrated rapid onset of analgesia (within 10 minutes), and had a sustained effect. PMID:17708123

Slatkin, Neal E; Xie, Fang; Messina, John; Segal, Thalia J

64

Upper bounds on fault tolerance thresholds of noisy Clifford-based quantum computers  

NASA Astrophysics Data System (ADS)

We consider the possibility of adding noise to a quantum circuit to make it efficiently simulatable classically. In previous works, this approach has been used to derive upper bounds to fault tolerance thresholds—usually by identifying a privileged resource, such as an entangling gate or a non-Clifford operation, and then deriving the noise levels required to make it 'unprivileged'. In this work, we consider extensions of this approach where noise is added to Clifford gates too and then 'commuted' around until it concentrates on attacking the non-Clifford resource. While commuting noise around is not always straightforward, we find that easy instances can be identified in popular fault tolerance proposals, thereby enabling sharper upper bounds to be derived in these cases. For instance we find that if we take Knill's (2005 Nature 434 39) fault tolerance proposal together with the ability to prepare any possible state in the XY plane of the Bloch sphere, then not more than 3.69% error-per-gate noise is sufficient to make it classical, and 13.71% of Knill's ? noise model is sufficient. These bounds have been derived without noise being added to the decoding parts of the circuits. Introducing such noise in a toy example suggests that the present approach can be optimized further to yield tighter bounds.

Plenio, M. B.; Virmani, S.

2010-03-01

65

Sex Differences in Clinical Pain: A Multisample Study  

Microsoft Academic Search

A recent meta-analysis of the experimental pain literature revealed effect sizes of .55 for pain threshold and .57 for pain tolerance, indicating a moderate difference in pain perception between men and women, with women reporting an increased sensitivity to pain. The current study investigated the relationship between sex and clinical pain ratings, in patients seeking care at a tertiary care

Michael E. Robinson; Emily A. Wise; Joseph L. Riley III; James W. Atchison

1998-01-01

66

Tonic Descending Facilitation from the Rostral Ventromedial Medulla Mediates Opioid-Induced Abnormal Pain and Antinociceptive Tolerance  

Microsoft Academic Search

Many clinical case reports have suggested that sustained opi- oid exposure can elicit unexpected, paradoxical pain. Here, we explore the possibility that (1) opioid-induced pain results from tonic activation of descending pain facilitation arising in the rostral ventromedial medulla (RVM) and (2) the presence of such pain manifests behaviorally as antinociceptive tolerance. Rats implanted subcutaneously with pellets or osmotic minipumps

Todd W. Vanderah; Nova M. H. Suenaga; Michael H. Ossipov; T. Philip; Josephine Lai

2001-01-01

67

Threshold temperatures mediate the impact of reduced snow cover on overwintering freeze-tolerant caterpillars  

NASA Astrophysics Data System (ADS)

Decreases in snow cover due to climate change could alter the energetics and physiology of ectothermic animals that overwinter beneath snow, yet how snow cover interacts with physiological thresholds is unknown. We applied numerical simulation of overwintering metabolic rates coupled with field validation to determine the importance of snow cover and freezing to the overwintering lipid consumption of the freeze-tolerant Arctiid caterpillar Pyrrharctia isabella. Caterpillars that overwintered above the snow experienced mean temperatures 1.3°C lower than those below snow and consumed 18.36 mg less lipid of a total 68.97-mg reserve. Simulations showed that linear temperature effects on metabolic rate accounted for only 30% of the difference in lipid consumption. When metabolic suppression by freezing was included, 93% of the difference between animals that overwintered above and below snow was explained. Our results were robust to differences in temperature sensitivity of metabolic rate, changes in freezing point, and the magnitude of metabolic suppression by freezing. The majority of the energy savings was caused by the non-continuous reduction in metabolic rate due to freezing, the first example of the importance of temperature thresholds in the lipid use of overwintering insects.

Marshall, Katie E.; Sinclair, Brent J.

2012-01-01

68

Microglia: a promising target for treating neuropathic and postoperative pain, and morphine tolerance.  

PubMed

Management of chronic pain, such as nerve-injury-induced neuropathic pain associated with diabetic neuropathy, viral infection, and cancer, is a real clinical challenge. Major surgeries, such as breast and thoracic surgery, leg amputation, and coronary artery bypass surgery, also lead to chronic pain in 10-50% of individuals after acute postoperative pain, partly due to surgery-induced nerve injury. Current treatments mainly focus on blocking neurotransmission in the pain pathway and have only resulted in limited success. Ironically, chronic opioid exposure might lead to paradoxical pain. Development of effective therapeutic strategies requires a better understanding of cellular mechanisms underlying the pathogenesis of neuropathic pain. Progress in pain research points to an important role of microglial cells in the development of chronic pain. Spinal cord microglia are strongly activated after nerve injury, surgical incision, and chronic opioid exposure. Increasing evidence suggests that, under all these conditions, the activated microglia not only exhibit increased expression of microglial markers CD 11 b and Iba 1, but also display elevated phosphorylation of p38 mitogen-activated protein kinase. Inhibition of spinal cord p38 has been shown to attenuate neuropathic and postoperative pain, as well as morphine-induced antinociceptive tolerance. Activation of p38 in spinal microglia results in increased synthesis and release of the neurotrophin brain-derived neurotrophic factor and the proinflammatory cytokines interleukin-1?, interleukin-6, and tumor necrosis factor-?. These microglia-released mediators can powerfully modulate spinal cord synaptic transmission, leading to increased excitability of dorsal horn neurons, that is, central sensitization, partly via suppressing inhibitory synaptic transmission. Here, we review studies that support the pronociceptive role of microglia in conditions of neuropathic and postoperative pain and opioid tolerance. We conclude that targeting microglial signaling might lead to more effective treatments for devastating chronic pain after diabetic neuropathy, viral infection, cancer, and major surgeries, partly via improving the analgesic efficacy of opioids. PMID:21783017

Wen, Yeong-Ray; Tan, Ping-Heng; Cheng, Jen-Kun; Liu, Yen-Chin; Ji, Ru-Rong

2011-08-01

69

Virtual-reality distraction and cold-pressor pain tolerance: does avatar point of view matter?  

PubMed

This study tested the effects of distraction using virtual-reality (VR) technology on acute pain tolerance in young adults. Forty-one undergraduate students, aged 18-23 years, used a VR head-mounted display helmet, steering wheel, and foot pedal to play an auto racing video game while undergoing exposure to very cold water (cold pressor set at 1 °C). Two different game views were tested that were hypothesized to affect the degree to which participants felt "present" in the virtual environment: a first-person view, in which the participant saw the virtual environment through the eyes of the game character being manipulated; and a third-person view, in which the participant viewed the game character from a distance. The length of time participants tolerated the cold-water exposure (pain tolerance) under each distraction condition was compared to a baseline (no distraction) trial. Subjects also rated the degree to which they felt "present" in the virtual environment after each distraction trial. Results demonstrated that participants had significantly higher pain tolerance during both VR-distraction conditions relative to baseline (no distraction) trials. Although participants reported a greater sense of presence during the first-person condition than the third-person condition, pain-tolerance scores associated with the two distraction conditions did not differ. The types of VR applications in which presence may be more or less important are discussed. PMID:20950186

Dahlquist, Lynnda M; Herbert, Linda J; Weiss, Karen E; Jimeno, Monica

2010-04-03

70

Threshold of Musculoskeletal Pain Intensity for Increased Risk of Long-Term Sickness Absence among Female Healthcare Workers in Eldercare  

PubMed Central

Purpose Musculoskeletal disorders increase the risk for absenteeism and work disability. However, the threshold when musculoskeletal pain intensity significantly increases the risk of sickness absence among different occupations is unknown. This study estimates the risk for long-term sickness absence (LTSA) from different pain intensities in the low back, neck/shoulder and knees among female healthcare workers in eldercare. Methods Prospective cohort study among 8,732 Danish female healthcare workers responding to a questionnaire in 2004–2005, and subsequently followed for one year in a national register of social transfer payments (DREAM). Using Cox regression hazard ratio (HR) analysis we modeled risk estimates of pain intensities on a scale from 0–9 (reference 0, where 0 is no pain and 9 is worst imaginable pain) in the low back, neck/shoulders and knees during the last three months for onset of LTSA (receiving sickness absence compensation for at least eight consecutive weeks) during one-year follow-up. Results During follow-up, the 12-month prevalence of LTSA was 6.3%. With adjustment for age, BMI, smoking and leisure physical activity, the thresholds of pain intensities significantly increasing risk of LTSA for the low back (HR 1.44 [95%CI 1.07–1.93]), neck/shoulders (HR 1.47 [95%CI 1.10–1.96]) and knees (HR 1.43 [95%CI 1.06–1.93]) were 5, 4 and 3 (scale 0–9), respectively, referencing pain intensity of 0. Conclusion The threshold of pain intensity significantly increasing the risk for LTSA among female healthcare workers varies across body regions, with knee pain having the lowest threshold. This knowledge may be used in the prevention of LTSA among health care workers.

Andersen, Lars L.; Clausen, Thomas; Burr, Hermann; Holtermann, Andreas

2012-01-01

71

Tolerance of Pain by Cancer Patients in Hyperthermia Treatment  

Microsoft Academic Search

Hyperthermia-the artificial inducement of abnormally high blood temperature-is designed to cause tumor tissue to retain heat and has additive or synergistic effects with radiation and chemotherapy. Because of the clinically administered high temperature, cancer patients often experience pain and discomfort. In the study described in this article, 30 cancer patients undergoing hyperthermia treatment as part of their overall cancer care

Ronald H. Rozensky; Laurie Feldman Honor; Steve M. Tovian; Gordon Herz; Margaret Holland

1985-01-01

72

Nociceptive flexion reflex thresholds and pain during rest and computer game play in patients with hypertension and individuals at risk for hypertension  

PubMed Central

Supraspinal pain modulation may explain hypertensive hypoalgesia. We compared nociceptive flexion reflex (NFR) thresholds and pain during rest and computer game play in hypertensives and normotensives (Experiment 1) and normotensives with and without hypertensive parents (Experiment 2). The game was selected to modulate activity in pain pathways. NFR thresholds did not differ between groups during rest or game play. Pain ratings never differed between hypertensives and normotensives, whereas individuals with hypertensive parents reported less pain during the first two NFR assessments, compared to those without. NFR thresholds and pain were reduced by game play compared to rest. The failure of game play to differentially modulate NFR thresholds or associated pain reports between groups argues against enhanced supraspinal modulation of nociception and pain in hypertensives and those at increased risk for hypertension.

Edwards, Louisa; Ring, Christopher; France, Christopher R.; al'Absi, Mustafa; McIntyre, David; Carroll, Douglas; Martin, Una

2007-01-01

73

Pronociceptive effects of spinal dynorphin promote cannabinoid-induced pain and antinociceptive tolerance  

Microsoft Academic Search

Recent studies indicate that sustained opioid administration produces increased expression of spinal dynorphin, which promotes enhanced sensitivity to non-noxious and noxious stimuli. Such increased ‘pain’ may manifest behaviorally as a decrease in spinal antinociceptive potency. Here, the possibility of similar mechanisms in the antinociception of spinal cannabinoids was explored. Response thresholds to non-noxious mechanical and noxious thermal stimuli were assessed.

L. R Gardell; S. E Burgess; A Dogrul; M. H Ossipov; T. P Malan; J Lai; F Porreca

2002-01-01

74

Opioid Tolerance and Hyperalgesia in Chronic Pain Patients After One Month of Oral Morphine Therapy: A Preliminary Prospective Study  

Microsoft Academic Search

There is accumulating evidence that opioid therapy might not only be associated with the development of tolerance but also with an increased sensitivity to pain, a condition referred to as opioid-induced hyperalgesia (OIH). However, there are no prospective studies documenting the development of opioid tolerance or OIH in patients with chronic pain. This preliminary study in 6 patients with chronic

Larry F. Chu; David J. Clark; Martin S. Angst

2006-01-01

75

The Impact of Demand Characteristics on Brief Acceptance- and Control-Based Interventions for Pain Tolerance  

ERIC Educational Resources Information Center

|The present analog study compared the effectiveness of an acceptance- and control-based intervention on pain tolerance using a cold pressor task, and is a partial replication and extension of the Hayes, Bissett et al. (Hayes, S. C., Bissett, R.T., Korn, Z., Zettle, R. D., Rosenfarb, I. S., Cooper, L. D., & Grundt, A. M. (1999). "The impact of…

Roche, Bryan; Forsyth, John P.; Maher, Elaine

2007-01-01

76

Sedation and analgesia for colonoscopy: patient tolerance, pain, and cardiorespiratory parameters  

Microsoft Academic Search

Background: Colonoscopy is generally performed with the patient sedated and receiving analgesics. However, the benefit of the most often used combination of intravenous midazolam and pethidine on patient tolerance and pain and its cardiorespiratory risk have not been fully defined. Methods: In this double-blind prospective study, 150 outpatients undergoing routine colonoscopy were randomly assigned to receive either (1) low-dose midazolam

Florian Froehlich; Joël Thorens; Werner Schwizer; Martin Preisig; Manfred Köhler; Ron D. Hays; Michael Fried; Jean-Jacques Gonvers

1997-01-01

77

Chronic morphine use does not induce peripheral tolerance in a rat model of inflammatory pain  

PubMed Central

Although opioids are highly effective analgesics, they are also known to induce cellular adaptations resulting in tolerance. Experimental studies are often performed in the absence of painful tissue injury, which precludes extrapolation to the clinical situation. Here we show that rats with chronic morphine treatment do not develop signs of tolerance at peripheral ?-opioid receptors (?-receptors) in the presence of painful CFA-induced paw inflammation. In sensory neurons of these animals, internalization of ?-receptors was significantly increased and G protein coupling of ?-receptors as well as inhibition of cAMP accumulation were preserved. Opioid receptor trafficking and signaling were reduced, and tolerance was restored when endogenous opioid peptides in inflamed tissue were removed by antibodies or by depleting opioid-producing granulocytes, monocytes, and lymphocytes with cyclophosphamide (CTX). Our data indicate that the continuous availability of endogenous opioids in inflamed tissue increases recycling and preserves signaling of ?-receptors in sensory neurons, thereby counteracting the development of peripheral opioid tolerance. These findings infer that the use of peripherally acting opioids for the prolonged treatment of inflammatory pain associated with diseases such as chronic arthritis, inflammatory neuropathy, or cancer, is not necessarily accompanied by opioid tolerance.

Zollner, Christian; Mousa, Shaaban A.; Fischer, Oliver; Rittner, Heike L.; Shaqura, Mohammed; Brack, Alexander; Shakibaei, Mehdi; Binder, Waltraud; Urban, Florian; Stein, Christoph; Schafer, Michael

2008-01-01

78

Chronic morphine use does not induce peripheral tolerance in a rat model of inflammatory pain.  

PubMed

Although opioids are highly effective analgesics, they are also known to induce cellular adaptations resulting in tolerance. Experimental studies are often performed in the absence of painful tissue injury, which precludes extrapolation to the clinical situation. Here we show that rats with chronic morphine treatment do not develop signs of tolerance at peripheral mu-opioid receptors (micro-receptors) in the presence of painful CFA-induced paw inflammation. In sensory neurons of these animals, internalization of mu-receptors was significantly increased and G protein coupling of mu-receptors as well as inhibition of cAMP accumulation were preserved. Opioid receptor trafficking and signaling were reduced, and tolerance was restored when endogenous opioid peptides in inflamed tissue were removed by antibodies or by depleting opioid-producing granulocytes, monocytes, and lymphocytes with cyclophosphamide (CTX). Our data indicate that the continuous availability of endogenous opioids in inflamed tissue increases recycling and preserves signaling of mu-receptors in sensory neurons, thereby counteracting the development of peripheral opioid tolerance. These findings infer that the use of peripherally acting opioids for the prolonged treatment of inflammatory pain associated with diseases such as chronic arthritis, inflammatory neuropathy, or cancer, is not necessarily accompanied by opioid tolerance. PMID:18246198

Zöllner, Christian; Mousa, Shaaban A; Fischer, Oliver; Rittner, Heike L; Shaqura, Mohammed; Brack, Alexander; Shakibaei, Mehdi; Binder, Waltraud; Urban, Florian; Stein, Christoph; Schäfer, Michael

2008-03-01

79

Fentanyl buccal tablet: in breakthrough pain in opioid-tolerant patients with cancer.  

PubMed

The fentanyl buccal tablet (FBT) is a new formulation of fentanyl that uses an effervescent drug delivery system to enhance penetration across the buccal mucosa for the treatment of breakthrough pain in opioid-tolerant patients with cancer. Fentanyl is rapidly absorbed from FBT across the buccal mucosa and into the bloodstream. Fentanyl is more rapidly absorbed and bioavailability is higher from FBT than from the oral transmucosal fentanyl citrate formulation. In a well designed phase III trial in opioid-tolerant patients with cancer, a single dose of FBT 100-800 microg provided clinically significant improvements in pain intensity from 15 to 60 minutes after the dose. Single FBT doses of 100-800 microg were generally well tolerated; the majority of adverse events were mild to moderate in nature and typical of those associated with opioids. PMID:17181383

Blick, Stephanie K A; Wagstaff, Antona J

2006-01-01

80

Peripheral and electrocortical responses to painful and non-painful stimulation in chronic pain patients, tension headache patients and healthy controls  

Microsoft Academic Search

Sixteen chronic back pain (CBP) patients, 16 tension headache (THA) patients and 16 healthy controls (HC) were exposed to four series of ten electric stimuli at perception threshold, pain threshold and 10% below pain tolerance. The EEG was recorded from three sites, in addition, the EMG from the m. frontalis and m. erector spinae, heart rate and skin conductance were

Herta Flor; Martin Diers; Niels Birbaumer

2004-01-01

81

[Efficacy and tolerability of controlled-release oxycodone against nab-paclitaxel-induced musculoskeletal pain in breast cancer patients].  

PubMed

Paclitaxel therapy often causes musculoskeletal pain, and some clinical studies have indicated that this pain is due to nerve injury, rather than muscle or joint lesion. We report four clinical cases in which controlled-release oxycodone improved pain intensity in breast cancer patients with severe musculoskeletal pain caused by nab-paclitaxel therapy. In each case, oxycodone was well-tolerated and the symptoms of peripheral neuropathy were quite mild, indicating that oxycodone exhibited a preventive or therapeutic effect on peripheral neuropathy. Therefore, oxycodone may have favorable efficacy and tolerability against cancer therapy-related pain with a neuropathic element in breast cancer patients. PMID:23986044

Inoue, Kenichi; Ohkubo, Fumie; Nagai, Shigenori; Tsuboi, Miki; Kubo, Kazuyuki; Kurozumi, Ken; Hayashi, Yuji; Matsumoto, Hiroshi; Takei, Hiroyuki

2013-08-01

82

Test-retest reliability of the nociceptive withdrawal reflex and electrical pain thresholds after single and repeated stimulation in patients with chronic low back pain.  

PubMed

Recent studies have shown that the nociceptive withdrawal reflex threshold (NWR-T) and the electrical pain threshold (EP-T) are reliable measures in pain-free populations. However, it is necessary to investigate the reliability of these measures in patients with chronic pain in order to translate these techniques from laboratory to clinic. The aims of this study were to determine the test-retest reliability of the NWR-T and EP-T after single and repeated (temporal summation) electrical stimulation in a group of patients with chronic low back pain, and to investigate the association between the NWR-T and the EP-T. To this end, 25 patients with chronic pain participated in three identical sessions, separated by 1 week in average, in which the NWR-T and the EP-T to single and repeated stimulation were measured. Test-retest reliability was assessed using intra-class correlation coefficient (ICC), coefficient of variation (CV), and Bland-Altman analysis. The association between the thresholds was assessed using the coefficient of determination (r (2)). The results showed good-to-excellent reliability for both NWR-T and EP-T in all cases, with average ICC values ranging 0.76-0.90 and average CV values ranging 12.0-17.7%. The association between thresholds was better after repeated stimulation than after single stimulation, with average r (2) values of 0.83 and 0.56, respectively. In conclusion, the NWR-T and the EP-T are reliable assessment tools for assessing the sensitivity of spinal nociceptive pathways in patients with chronic pain. PMID:20814801

Biurrun Manresa, José A; Neziri, Alban Y; Curatolo, Michele; Arendt-Nielsen, Lars; Andersen, Ole K

2010-09-03

83

Rectal distention testing in patients with irritable bowel syndrome: Sensitivity, specificity, and predictive values of pain sensory thresholds  

Microsoft Academic Search

Background & Aims: Visceral hypersensitivity was detected in patients with functional gastrointestinal disorders and has been proposed as a biological marker of irritable bowel syndrome (IBS). The purpose of this study was to assess the sensitivity, specificity, and the predictive values of pain thresholds evaluated by rectal distention using an electronic barostat in patients with or without IBS and in

Mickael Bouin; Victor Plourde; Michel Boivin; Monique Riberdy; France Lupien; Marie Laganière; Pierre Verrier; Pierre Poitras

2002-01-01

84

Gender differences in pain ratings and pupil reactions to painful pressure stimuli  

Microsoft Academic Search

In order to investigate gender differences in pain perception, the present study employed both a psychophysical and a psychophysiological measure. In experiment 1, 20 subjects rated the painfulness of 4 different levels of tonic pressure applied to their fingers using a verbally anchored categorization procedure. In general agreement with studies of pain threshold and tolerance, female subjects reported greater pain

Wolfgang Ellermeier; Wolfgang Westphal

1995-01-01

85

The relationship of depression and somatic focus to experimental and clinical pain in chronic pain patients  

Microsoft Academic Search

The present study examined Fields' proposal that depression increases the sensory experience of pain in part through greater somatic focus. Experimental and clinical pain measures were compared to self-report of depression and somatic focus in 60 chronic pain patients. Depression scores were unrelated to pain threshold or tolerance on the cold-pressor test. However, as hypothesized by Fields, path analytic models

Michael E. Geisser; Melodye E. Gaskin; Michael E. Robinson; Anthony F. Greene

1993-01-01

86

Reactions to pain among subjects high and low in dental fear  

Microsoft Academic Search

Differential pain tolerance might account for the diversity of reactions commonly seen in response to stressful medical and dental procedures. College students reporting themselves either highly fearful or nonfearful of dental work were compared in several aspects of their reactions to dental and nondental pain. The two groups did not differ in pain threshold or pain tolerance assessed during tooth

Robert K. Klepac; Marvin McDonald; Gregory Hauge; John Dowling

1980-01-01

87

Self-reported somatosensory symptoms of neuropathic pain in fibromyalgia and chronic widespread pain correlate with tender point count and pressure-pain thresholds  

Microsoft Academic Search

Widespread pain and pain hypersensitivity are the hallmark of fibromyalgia, a complex pain condition linked to central sensitization. In this study the painDETECT questionnaire (PDQ), validated to identify neuropathic pain and based on pain quality items, was applied in a cross-sectional sample of patients with chronic widespread pain (CWP). The aims of the study were to assess the patient-reported sensory

Kirstine Amris; Anders Jespersen; Henning Bliddal

2010-01-01

88

Long-term tolerability, efficacy and acceptability of fentanyl pectin nasal spray for breakthrough cancer pain  

Microsoft Academic Search

Purpose  Previous studies show that fentanyl pectin nasal spray (FPNS) rapidly provides clinically meaningful pain relief in the treatment\\u000a of breakthrough cancer pain (BTCP). This study assessed the long-term tolerability, acceptability and consistency of effect\\u000a of FPNS in patients with BTCP.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Patients (new and rolled over from earlier controlled studies) with cancer experiencing one to four episodes per day of BTCP

Lukas Radbruch; Luis M. Torres; John E. Ellershaw; Antonio Gatti; Guillermo Luis Lerzo; Julia Revnic; Donald Taylor

89

The effect of target-controlled infusion of low-dose ketamine on heat pain and temporal summation threshold  

Microsoft Academic Search

Purpose  We investigated the heat pain threshold (HPT) and temporal summation threshold (TST) before and after target-controlled infusion\\u000a (TCI) of ketamine with an effect-site concentration (Ce) of 30 and 60 ng\\/ml.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Healthy young volunteers (n = 20) were enrolled. A thermode was applied to the volar side of each volunteer’s right forearm, and HPT and TST were measured\\u000a before and after TCI of ketamine.

Joon-Ho Lee; Sung-Hwan Cho; Sang-Hyun Kim; Won-Soek Chae; Hee-Cheol Jin; Jeong-Seok Lee; Yong-Ik Kim

2011-01-01

90

Sativex: clinical efficacy and tolerability in the treatment of symptoms of multiple sclerosis and neuropathic pain.  

PubMed

Sativex is one of the first cannabis-based medicines to undergo conventional clinical development and to be approved as a prescription medicine. It is an oromucosal spray that allows flexible, individualised dosing. Patients self titrate their overall dose and pattern of dosing according to their response to and tolerance of the medicine. This usually results in the administration of approximately 8-12 sprays/day. Each spray delivers tetrahydrocannabinol 2.7 mg and cannabidiol 2.5 mg, giving an approximate average dose of tetrahydrocannabinol 22-32 mg/day and cannabidiol 20-30 mg/day. Development has concentrated on the treatment of symptoms of multiple sclerosis, notably spasticity and neuropathic pain, as well as the treatment of neuropathic pain of other aetiologies. Positive results in placebo-controlled trials of the use of Sativex as an add-on therapy in these indications demonstrate that Sativex is efficacious and well tolerated in the treatment of these symptoms. Sativex has been approved for use in neuropathic pain due to multiple sclerosis in Canada. If ongoing studies replicate the results already observed, further approvals for the treatment of spasticity in multiple sclerosis and for neuropathic pain are likely. PMID:16553576

Barnes, Michael Philip

2006-04-01

91

Clinical disorders and pressure-pain threshold of the forearm and hand among automobile assembly line workers.  

PubMed

The prevalence of forearm and hand disorders was examined by questionnaire and clinical examination in 199 automobile assembly line workers and in 186 controls. The pressure-pain threshold, hand grip force and hand anthropometry were also studied. There was an increased prevalence of de Quervain's disease for male automobile assembly line workers, and of carpal tunnel syndrome in female workers. The prevalence of symptoms in the forearm and hand during the last 7 days were twice as high among automobile assembly line workers than controls for both men and women. The occurrence of symptoms in the last 7 days was associated with de Quervain's disease, carpal tunnel syndrome and sick-leave due to forearm or hand problems, and it also influenced activities of daily living. Hand grip strength and anthropometrics were not associated with findings in the clinical examination or the occurrence of symptoms in the last 7 days. Low pressure-pain threshold was not associated with findings in the clinical examination, except for reported occurrence of symptoms in the last 7 days for women. Pressure-pain threshold as an indicator of tissue damage is discussed. PMID:8770741

Byström, S; Hall, C; Welander, T; Kilbom, A

1995-12-01

92

Sex-Related Influences on Pain: A Review of Mechanisms and Clinical Implications  

Microsoft Academic Search

Objective: To review the literature regarding gender-related influences on the experience of pain. Methods: Medline searches and reference lists were used to locate published articles regarding gender differences in pain. Results: Women are at increased risk for many clinical pain conditions and for increased severity of clinical pain relative to men. Women typically report lower pain threshold and tolerance and

Roger B. Fillingim

2003-01-01

93

Acute pain management in opioid-tolerant patients: a growing challenge.  

PubMed

In Australia and New Zealand, in parallel with other developed countries, the number of patients prescribed opioids on a long-term basis has grown rapidly over the last decade. The burden of chronic pain is more widely recognised and there has been an increase in the use of opioids for both cancer and non-cancer indications. While the prevalence of illicit opioid use has remained relatively stable, the diversion and abuse of prescription opioids has escalated, as has the number of individuals receiving methadone or buprenorphine pharmacotherapy for opioid addiction. As a result, the proportion of opioid-tolerant patients requiring acute pain management has increased, often presenting clinicians with greater challenges than those faced when treating the opioid-naïve. Treatment aims include effective relief of acute pain, prevention of drug withdrawal, assistance with any related social, psychiatric and behavioural issues, and ensuring continuity of long-term care. Pharmacological approaches incorporate the continuation of usual medications (or equivalent), short-term use of sometimes much higher than average doses of additional opioid, and prescription of non-opioid and adjuvant drugs, aiming to improve pain relief and attenuate opioid tolerance and/or opioid-induced hyperalgesia. Discharge planning should commence at an early stage and may involve the use of a 'Reverse Pain Ladder' aiming to limit duration of additional opioid use. Legislative requirements may restrict which drugs can be prescribed at the time of hospital discharge. At all stages, there should be appropriate and regular consultation and liaison with the patient, other treating teams and specialist services. PMID:21970125

Huxtable, C A; Roberts, L J; Somogyi, A A; MacIntyre, P E

2011-09-01

94

Transdermal Lidocaine and Ketamine for Neuropathic Pain: A Study of Effectiveness and Tolerability  

PubMed Central

Background: Acute neuropathic pain is a common disorder. Transdermal cream could be an alternative to oral medications. Objective: To evaluate the effectiveness and tolerability of transdermal Lidocaine and Ketamine for acute neuropathic pain. Study Design: Retrospective chart review Setting: University-affiliated outpatient Physiatry clinic Methods: articipants: neuropathic pain with a prescription of a transdermal cream containing Lidocaine and Ketamine. Ef-fectiveness was evaluated by the number of patients with improvement divided by the total number of patients who re-ceived a prescription of the cream. Results: A total of 854 patient charts were reviewed. Twenty-one patients with symptoms, signs, and/or a documented di-agnosis of neuropathic pain and had been given a prescription of a transdermal preparation containing Lidocaine and Ketamine. Four groups were identified: those with a clearly stated diagnosis of neuropathic pain and prescribed a transdermal compound containing Lidocaine and Ketamine with follow-up (Group A) or without follow-up (Group B), and those with a suggested diagnosis of neuropathic pain with (Group C) or without follow-up (Group D). Effectiveness of the cream was seven out of eight (87%) for Group A and one out of three (33%) for Group C. In total, eight out of 11 patients (73%) benefited from a cream containing Lidocaine and Ketamine. Two patients experienced skin reactions that led to discontin-uation of treatment. Limitations: This is a retrospective chart review without control group. Conclusion: Transdermal cream containing Ketamine and Lidocaine was effective in 73% of patients with acute neuro-pathic pain and may be a good alternative to oral medications.

Tam, Emily; Furlan, Andrea D

2012-01-01

95

Sex differences and personality factors in responsivity to pain.  

PubMed

This study investigated the relationship between measured levels of masculinity-femininity, social desirability, and responsivity to pain in men and women. The literature suggests that the two personality variables might provide an explanation for the common findings of higher pain thresholds and tolerances in men than in women. A significant interaction was found between masculinity-femininity and sex for pain thresholds. Analysis of this interaction indicated that for men, but not women, there was a significant correlation between masculinity-femininity and pain, where higher masculinity was associated with higher pain thresholds. However, this finding did not account for the sex difference in pain threshold. The sex of the subject remained a significant predictor of both pain thresholds and tolerances after allowing for the influence of masculinity-femininity, social desirability, and their associated interactions. PMID:4069906

Otto, M W; Dougher, M J

1985-10-01

96

Ablation of estrogen receptor alpha or beta eliminates sex differences in mechanical pain threshold in normal and inflamed mice.  

PubMed

We examined nociceptive responses to mechanical stimulation in mice of both sexes lacking the estrogen receptor alpha or beta and in respective wild types under normal conditions, after inflammation of a hindpaw or peripheral nerve injury. In normal wild-type mice, females had significantly lower paw withdrawal threshold than males. There was no significant difference between wild-type mice and knock-outs of either estrogen receptor alpha or beta in mechanical response threshold in male mice. However, significantly elevated response threshold was observed in both knock-out female mice, which eliminated sex differences in nociception. After carrageenan-induced inflammation of a hindpaw, all wild-type and knock-out mice exhibited similar local edema with no difference between the sexes. Wild-type mice developed hypersensitivity (allodynia) to mechanical stimulation, which was more profound in the females than in males. Again, such sex difference was not observed in the knock-outs of either estrogen receptor. Photochemically induced partial sciatic nerve injury caused similar persistent mechanical hypersensitivity in the wild types and both estrogen receptor knock-outs with no difference between the sexes. These results suggest that the sex difference in basal mechanical pain threshold and inflammatory hypersensitivity is eliminated in mice lacking either the estrogen alpha receptors or beta receptors. However, these receptors do not seem to be directly involved in mediating pain sensitivity in general or in the development of neuropathic pain. It is unclear whether the elimination of sex differences observed in the knock-outs reflects an ongoing effect of estrogen acting through its receptors in females or the developmental changes that predominantly affect females. PMID:19285805

Li, Lili; Fan, Xiaotang; Warner, Margaret; Xu, Xiao-Jun; Gustafsson, Jan-Ake; Wiesenfeld-Hallin, Zsuzsanna

2009-03-13

97

High-power pain threshold ultrasound technique in the treatment of active myofascial trigger points: a randomized, double-blind, case-control study  

Microsoft Academic Search

Majlesi J, Ünalan H. High-power pain threshold ultrasound technique in the treatment of active myofascial trigger points: a randomized, double-blind, case-control study. Arch Phys Med Rehabil 2004;85:833-6.

Javid Majlesi; Halil Ünalan

2004-01-01

98

Comparison of High-Power Pain Threshold Ultrasound Therapy With Local Injection in the Treatment of Active Myofascial Trigger Points of the Upper Trapezius Muscle  

Microsoft Academic Search

Unalan H, Majlesi J, Aydin FY, Palamar D. Comparison of high-power pain threshold ultrasound therapy with local ?njection in the treatment of active myofascial trigger points of the upper trapezius muscle.

Halil Unalan; Javid Majlesi; Filiz Yildiz Aydin; Deniz Palamar

2011-01-01

99

Use of Intravenous Fentanyl Against Morphine Tolerance in Breakthrough Cancer Pain: A Case Series and Literature Review.  

PubMed

Palliative care physicians are accustomed to using transdermal fentanyl patch for cancer pain control but not so familiar with its intravenous administration. Historically, fentanyl has been used to treat breakthrough pain because it is a very potent analgesic with a rapid onset and short duration of action. Although several formulations of fentanyl have been recently developed for breakthrough cancer pain, these are unavailable or too expensive in some countries. Also, all opioids can induce tolerance potentially and different opioids cause significantly different degrees of tolerance. Therefore, sequential opioid trials may be a reasonable approach in patients with poor analgesic effect after dose escalation. Here, we present 2 morphine-tolerant patients with cancer in whom the intravenous fentanyl was effectively used for their refractory breakthrough pain. PMID:23345613

Hwang, In Cheol; Bruera, Eduardo; Park, Sang Min

2013-01-22

100

Effect of brief mindfulness intervention on tolerance and distress of pain induced by cold-pressor task.  

PubMed

A number of studies have demonstrated that short-term meditation intervention can lead to greater tolerance and lower pain or distress ratings of experimentally induced pain. However, few attempts have been made to examine the effects of short-term mindfulness-based intervention on the tolerance and distress of pain, when delivered in a therapist-free form. The present research explored the effect of brief mindfulness intervention using pre-recorded instruction on pain experimentally induced by the cold-pressor task. The effects of the mindfulness strategy, the distraction strategy and spontaneous strategy, all through the instructions of pre-recorded voices, were compared. The subjects were drawn from healthy college students and randomly assigned to the aforementioned three groups. Our results showed that compared with using spontaneous strategies, the mindfulness intervention significantly improved the participants' pain tolerance and reduced their immersion distress. The distraction strategy also significantly improved the participants' pain tolerance. However, it did not have a significant effect on the participants' level of distress during the immersion period. Our results suggest that brief mindfulness intervention without a therapist's personal involvement is capable of helping people cope with pain induced by the cold-pressor task. PMID:22961992

Liu, Xinghua; Wang, Sisi; Chang, Shaochen; Chen, Wenjun; Si, Mei

2012-09-07

101

Visceral pain decreases tolerance to blood loss in conscious female but not male rabbits.  

PubMed

Pain is a component of traumatic blood loss, yet little is known about how pain alters the response to blood loss in conscious animals. We evaluated the effects of colorectal distension on the cardiorespiratory response to blood loss in six male and six female conscious, chronically instrumented New Zealand White rabbits. The goal of these experiments was to test the hypotheses that 1) colorectal distension would increase tolerance to hemorrhage (i.e., increase the blood loss required to decrease mean arterial pressure tolerance would be similar in male and female rabbits. For hemorrhage, venous blood was withdrawn until mean arterial pressure decreased to tolerance to blood loss in males or females as hypothesized but instead decreased tolerance to blood loss only in females. PMID:17522119

Shafford, Heidi L; Schadt, James C

2007-05-23

102

The Fine Tuning of Pain Thresholds: A Sophisticated Double Alarm System  

Microsoft Academic Search

Two distinctive features characterize the way in which sensations including pain, are evoked by heat: (1) a thermal stimulus is always progressive; (2) a painful stimulus activates two different types of nociceptors, connected to peripheral afferent fibers with medium and slow conduction velocities, namely A?- and C-fibers. In the light of a recent study in the rat, our objective was

Léon Plaghki; Céline Decruynaere; Paul Van Dooren; Daniel Le Bars

2010-01-01

103

Habitat selection and ranges of tolerance: how do species differ beyond critical thresholds?  

PubMed Central

Sensitivity to habitat fragmentation often has been examined in terms of thresholds in landscape composition at which a species is likely to occur. Observed thresholds often have been low or absent, however, leaving much unexplained about habitat selection beyond initial thresholds of occurrence, even for species with strong habitat preferences. We examined responses to varying amounts of tree cover, a widely influential measure of habitat loss, for 40 woodland bird species in a mixed woodland/grassland landscape in eastern North Dakota, USA. We used LOESS smoothing to describe incidence for each species at three scales: within 200, 400, and 1200 m around sample locations. For the 200-m scale, we also calculated the most-preferred range of tree cover (within which at least half of observations were predicted to occur) for each species. Only 10 of 40 species had occurrence thresholds greater than about 10% tree cover. After initial occurrence, species showed three general patterns: some increased monotonically with tree cover; some increased up to an asymptote; some peaked at intermediate amounts of tree cover and then declined. These patterns approximate selection for interior woodlands and for edge-rich environments, but incidence plots provide greater detail in landscape-scale selection than do those categories. For most species, patterns persisted at larger scales, but for some, larger scales had distinctly different patterns than local scales. Preferred ranges of tree cover varied from <20% tree cover (common grackle, Quiscalus quiscula) to >60% (veery, Catharus fuscescens). We conclude that incidence patterns provide more information on habitat selection than do threshold measures for most species: in particular, they differentiate species preferring concentrated woodlands from those preferring mixed landscapes, and they show contrasting degrees of selectiveness. [Correction added on 16 October 2012, after first online publication: the Abstract section has been reworded].

Cunningham, Mary Ann; Johnson, Douglas H

2012-01-01

104

Threshold of pain in chronic magnetic field- (50 Hz, 17.9 microT) exposed rats: effect of sucrose ingestion.  

PubMed

Both magnetic field (MF) exposure and sucrose ingestion produce opioid mediated analgesia, independently. This article addresses the query whether or not sucrose ingestion potentiates the analgesia of MF exposure. The pain threshold, as reflected by withdrawal of tail (thresholds of tail flick, TF), vocalization during stimulus (VD), and vocalization after stimulus (VA) were determined in 7 sessions at 0, 5, 10, 15, 30, 45, and 60 min, respectively (control rats). After an interval of 24 h the rats were provided with sucrose solution and were allowed to ingest it for 10 min. The pain thresholds were determined (Control sucrose-fed rats). The rats then received exposure to magnetic field (50 Hz, 17.9 microT) for 7 d (8 h/d) (MF-exposed rats) and the effect of sucrose ingestion was repeated (MF-Sucrose-fed rats). The basal threshold of pain did not vary in between the control and MF-exposed rats. Pain threshold during sessions II-VII did not vary in control rats but it increased in MF rats. Moreover, the pain thresholds were elevated in MF rats as compared to control rats. Sucrose-ingestion elevated the threshold of TF in controls but not in MF-exposed rats; while the thresholds of VA and VD were elevated more in control than MF rats. The results suggest that the MF exposure (50 Hz, 17.9 microT, 8 h/d) for 7 d did not affect the basal thresholds of pain, increased stress induced analgesia, and attenuated the sucrose ingestion-induced analgesia. PMID:18821201

Rakesh, Rishi M; Mathur, Rashmi

2008-01-01

105

Migraine, arousal and sleep deprivation: comment on: "sleep quality, arousal and pain thresholds in migraineurs: a blinded controlled polysomnographic study".  

PubMed

We discuss the hypothesis proposed by Engstrom and coworkers that Migraineurs have a relative sleep deprivation, which lowers the pain threshold and predispose to attacks. Previous data indicate that Migraineurs have a reduction of Cyclic Alternating Pattern (CAP), an essential mechanism of NREM sleep regulation which allows to dump the effect of incoming disruptive stimuli, and to protect sleep. The modifications of CAP observed in Migraineurs are similar to those observed in patients with impaired arousal (narcolepsy) and after sleep deprivation. The impairment of this mechanism makes Migraineurs more vulnerable to stimuli triggering attacks during sleep, and represents part of a more general vulnerability to incoming stimuli. PMID:23758606

Vollono, Catello; Testani, Elisa; Losurdo, Anna; Mazza, Salvatore; Della Marca, Giacomo

2013-06-10

106

Migraine, arousal and sleep deprivation: comment on: "sleep quality, arousal and pain thresholds in migraineurs: a blinded controlled polysomnographic study"  

PubMed Central

We discuss the hypothesis proposed by Engstrom and coworkers that Migraineurs have a relative sleep deprivation, which lowers the pain threshold and predispose to attacks. Previous data indicate that Migraineurs have a reduction of Cyclic Alternating Pattern (CAP), an essential mechanism of NREM sleep regulation which allows to dump the effect of incoming disruptive stimuli, and to protect sleep. The modifications of CAP observed in Migraineurs are similar to those observed in patients with impaired arousal (narcolepsy) and after sleep deprivation. The impairment of this mechanism makes Migraineurs more vulnerable to stimuli triggering attacks during sleep, and represents part of a more general vulnerability to incoming stimuli.

2013-01-01

107

Ferulic acid increases pain threshold and ameliorates depression-like behaviors in reserpine-treated mice: behavioral and neurobiological analyses.  

PubMed

Depression-pain dyad involves a series of pathological changes including the dysfunction of neuroendocrine and immune networks. Depression and pain influence each other, but the mechanisms are still obscure. The present study aimed to investigate the effect of ferulic acid (FA) on reserpine-induced pain and depression-like behaviors in mice. The results showed that reserpine (1 mg/kg for 3 days, i.p.) led to a significant decrease in nociceptive threshold in thermal hyperalgesia and mechanical allodynia, as well as a significant increase in the immobility time in mouse models of despair test. The neurochemical assays suggested the decreased neurotransmitters (dopamine, norepinephrine and serotonin) along with the increased oxidative stress, inflammatory cytokines, and apoptotic parameters in the frontal cortex and hippocampus of the reserpinised mice. Treatment with FA (40 or 80 mg/kg, p.o.) reversed the behavioral abnormalities and decreased norepinephrine, serotonin and dopamine levels in the hippocampus and frontal cortex induced by reserpine. The higher dose of FA effectively antagonized the oxidative and nitrosative stress and inflammation as evidenced by down-regulated nitrite, LPO, IL-1?, TNF-?, and up-regulated GSH and SOD. Furthermore, FA produced a dose dependent decrease in substance P, NF-?? p65 and caspase-3 levels in the frontal cortex and hippocampus of reserpinised mice. The findings suggest that FA exerts the effects on reserpine-induced pain and depression-like behaviors through regulating monoaminergic system, oxidative/antioxidant defense, inflammatory and apoptotic signaling pathways. Understanding the mechanism by which FA ameliorates depression and pain as a multi-targeted compound could open new avenues for the development of innovative treatments for depression coupled with pain. PMID:23584961

Xu, Ying; Zhang, Lu; Shao, Tuo; Ruan, Lina; Wang, Lin; Sun, Jiao; Li, Jianxin; Zhu, Xinbo; O'Donnell, James M; Pan, Jianchun

2013-04-14

108

Self-efficacy as a predictor of behavior change: Interaction with type of training for pain tolerance  

Microsoft Academic Search

The relationship between self-efficacy expectations and the training effects of skill-based and non-skill-based procedures for pain reduction was investigated. Both pretraining self-efficacy magnitude and strength measures, as well as changes in self-efficacy magnitude and strength, were employed to predict posttraining behavioral tolerance and subjective discomfort to a cold pressor pain stimulus. Eighty university women received brief training in either skill-based

T. Michael Vallis; Bradley Bucher

1986-01-01

109

Mid-thoracic tenderness: a comparison of pressure pain threshold between spinal regions, in asymptomatic subjects  

Microsoft Academic Search

Palpation for tenderness forms an important part of the manual therapy assessment for musculoskeletal dysfunction. In conjunction with other testing procedures it assists in establishing the clinical diagnosis. Tenderness in the thoracic spine has been reported in the literature as a clinical feature in musculoskeletal conditions where pain and dysfunction are located primarily in the upper quadrant. This study aimed

L. Keating; C. Lubke; V. Powell; T. Young; T. Souvlis; G. Jull

2001-01-01

110

Subgroups based on thermal and pressure pain thresholds in women with chronic whiplash display differences in clinical presentation - an explorative study  

PubMed Central

Purpose To investigate the presence of subgroups in chronic whiplash-associated disorders (WAD) based on pain thresholds for pressure (PPT), cold (CPT), and heat (HPT) and to compare these subgroups with respect to symptomatology, disability, and health aspects. Methods Two groups of female subjects – patients with chronic WAD (n = 28) and healthy controls (CON; n = 29) – were investigated. Quantitative sensory testing (QST) for thermal thresholds and algometry for PPT at four sites in the body (over the trapezius and tibialis anterior bilaterally) were determined. Habitual pain intensities, psychological strain, disability, and health aspects were registered using a questionnaire. Results A cluster analysis based on PPT, CPT, and HPT identified two subgroups of chronic WAD: one sensitive subgroup (s-WAD; n = 21), and one less sensitive subgroup (ls-WAD; n = 6). S-WAD displayed widespread hyperalgesia, whereas ls-WAD had localized hyperalgesia in the neck area, with tendencies to supernormal values in remote areas of the body. Generally, s-WAD had a significantly worse situation than the CON with respect to symptomatology, disability, and health aspects. The ls-WAD group was intermediary between s-WAD and CON in these aspects. Conclusion Different explanations, eg, severity of the pain condition per se, etiological factors, and pre-trauma differences in pain sensitivity, may exist for the differences in pain thresholds between the two subgroups. Future research should investigate the role of pain thresholds in the chronic stage to determine the efficacy of treatment interventions.

Borsbo, Bjorn; Liedberg, Gunilla M; Wallin, Mia; Gerdle, Bjorn

2012-01-01

111

The analgesic effect of codeine as compared to imipramine in different human experimental pain models  

Microsoft Academic Search

The hypoalgesic effect of single oral doses of 100 mg imipramine and 125 mg codeine was evaluated in a randomised, placebo-controlled, double-blind, 3-way cross-over experiment including 18 healthy volunteers. Pain tests were performed before and 90, 180, 270, 360 and 450 min after medication. The tests included determination of pain tolerance thresholds to pressure, pain detection\\/tolerance thresholds to single electrical

Thomas P Enggaard; Lars Poulsen; Lars Arendt-Nielsen; Steen Honoré Hansen; Inga Bjørnsdottir; Lars F Gram; Søren H Sindrup

2001-01-01

112

The influence of a series of five dry cupping treatments on pain and mechanical thresholds in patients with chronic non-specific neck pain - a randomised controlled pilot study  

PubMed Central

Background In this preliminary trial we investigated the effects of dry cupping, an ancient method for treating pain syndromes, on patients with chronic non-specific neck pain. Sensory mechanical thresholds and the participants' self-reported outcome measures of pain and quality of life were evaluated. Methods Fifty patients (50.5 ± 11.9 years) were randomised to a treatment group (TG) or a waiting-list control group (WL). Patients in the TG received a series of 5 cupping treatments over a period of 2 weeks; the control group did not. Self-reported outcome measures before and after the cupping series included the following: Pain at rest (PR) and maximal pain related to movement (PM) on a 100-mm visual analogue scale (VAS), pain diary (PD) data on a 0-10 numeric rating scale (NRS), Neck Disability Index (NDI), and health-related quality of life (SF-36). In addition, the mechanical-detection thresholds (MDT), vibration-detection thresholds (VDT), and pressure-pain thresholds (PPT) were determined at pain-related and control areas. Results Patients of the TG had significantly less pain after cupping therapy than patients of the WL group (PR: ?-22.5 mm, p = 0.00002; PM: ?-17.8 mm, p = 0.01). Pain diaries (PD) revealed that neck pain decreased gradually in the TG patients and that pain reported by the two groups differed significantly after the fifth cupping session (?-1.1, p = 0.001). There were also significant differences in the SF-36 subscales for bodily pain (?13.8, p = 0.006) and vitality (?10.2, p = 0.006). Group differences in PPT were significant at pain-related and control areas (all p < 0.05), but were not significant for MDT or VDT. Conclusions A series of five dry cupping treatments appeared to be effective in relieving chronic non-specific neck pain. Not only subjective measures improved, but also mechanical pain sensitivity differed significantly between the two groups, suggesting that cupping has an influence on functional pain processing. Trial registration The trial was registered at clinicaltrials.gov (NCT01289964).

2011-01-01

113

Evaluation of thermal, pain, and vibration sensation thresholds in newly diagnosed type 1 diabetic patients  

Microsoft Academic Search

Small and large fibre function was studied in 40 non-ketotic, newly diagnosed Type 1 diabetic patients and 48 age-matched controls, using 12 quantitative tests for assessment of cutaneous sensation. Patients were aged 10-39 years and had been treated with insulin for 4-31 days. Thermal discrimination (foot), warm and cold thermal perception (thenar eminence and foot), and heat and cold pain

D Ziegler; P Mayer; F A Gries

1988-01-01

114

A randomized, double-blind, placebo-controlled comparison of the analgesic efficacy, onset of action, and tolerability of ibuprofen arginate and ibuprofen in postoperative dental pain  

Microsoft Academic Search

Background: Because of its enhanced pharmacokinetic characteristics, ibuprofen arginate might be expected to provide faster pain relief than standard ibuprofen formulations in patients experiencing acute pain.Objective: This study assessed the analgesic efficacy, speed of onset, and tolerability of ibuprofen arginate compared with a commercially available form of ibuprofen in patients with postoperative dental pain.Methods: Patients were randomized to receive ibuprofen

Peter Black; Mitchell B. Max; Paul Desjardins; Thomas Norwood; Alfredo Ardia; Teresa Pallotta

2002-01-01

115

High-frequency transcutaneous peripheral nerve stimulation induces a higher increase of heat pain threshold in the cutaneous area of the stimulated nerve when confronted to the neighbouring areas.  

PubMed

Background. TENS (transcutaneous electrical nerve stimulation) is probably the most diffused physical therapy used for antalgic purposes. Although it continues to be used by trial and error, correct targeting of paresthesias evoked by the electrical stimulation on the painful area is diffusely considered very important for pain relief. Aim. To investigate if TENS antalgic effect is higher in the cutaneous area of the stimulated nerve when confronted to neighbouring areas. Methods. 10 volunteers (4 males, 6 females) underwent three different sessions: in two, heat pain thresholds (HPTs) were measured on the dorsal hand skin before, during and after electrical stimulation (100?Hz, 0.1?msec) of superficial radial nerve; in the third session HPTs, were measured without any stimulation. Results. Radial nerve stimulation induced an increase of HPT significantly higher in its cutaneous territory when confronted to the neighbouring ulnar nerve territory, and antalgic effect persisted beyond the stimulation time. Conclusions. The location of TENS electrodes is crucial for obtaining the strongest pain relief, and peripheral nerve trunk stimulation is advised whenever possible. Moreover, the present study indicates that continuous stimulation could be unnecessary, suggesting a strategy for avoiding the well-known tolerance-like effect of prolonged TENS application. PMID:24027756

Buonocore, M; Camuzzini, N; Cecini, M; Dalla Toffola, E

2013-08-06

116

High-Frequency Transcutaneous Peripheral Nerve Stimulation Induces a Higher Increase of Heat Pain Threshold in the Cutaneous Area of the Stimulated Nerve When Confronted to the Neighbouring Areas  

PubMed Central

Background. TENS (transcutaneous electrical nerve stimulation) is probably the most diffused physical therapy used for antalgic purposes. Although it continues to be used by trial and error, correct targeting of paresthesias evoked by the electrical stimulation on the painful area is diffusely considered very important for pain relief. Aim. To investigate if TENS antalgic effect is higher in the cutaneous area of the stimulated nerve when confronted to neighbouring areas. Methods. 10 volunteers (4 males, 6 females) underwent three different sessions: in two, heat pain thresholds (HPTs) were measured on the dorsal hand skin before, during and after electrical stimulation (100?Hz, 0.1?msec) of superficial radial nerve; in the third session HPTs, were measured without any stimulation. Results. Radial nerve stimulation induced an increase of HPT significantly higher in its cutaneous territory when confronted to the neighbouring ulnar nerve territory, and antalgic effect persisted beyond the stimulation time. Conclusions. The location of TENS electrodes is crucial for obtaining the strongest pain relief, and peripheral nerve trunk stimulation is advised whenever possible. Moreover, the present study indicates that continuous stimulation could be unnecessary, suggesting a strategy for avoiding the well-known tolerance-like effect of prolonged TENS application.

Buonocore, M.; Camuzzini, N.; Cecini, M.; Dalla Toffola, E.

2013-01-01

117

Pain Relief by Electrical Stimulation of the Central Gray Matter in Humans and Its Reversal by Naloxone  

Microsoft Academic Search

Relief of intractable pain was produced in six human patients by stimulation of electrodes permanently implanted in the periventricular and periaqueductal gray matter. The level of stimulation sufficient to induce pain relief seems not to alter the acute pain threshold. Indiscriminate repetitive stimulation produced tolerance to both stimulation-produced pain relief and the analgesic action of narcotic medication; this process could

Yoshio Hosobuchi; John E. Adams; Rita Linchitz

1977-01-01

118

The effect of high and low female sex hormone concentration on the two-point threshold of pain and touch and upon tactile sensitivity  

Microsoft Academic Search

In five normal women followed through eleven menstrual cycles a high concentration of female sex hormone (follicular fluid) in the blood corresponded with a lowered threshold for two-point touch and pain discriminations and with reduced tactile sensitivity. For similar conditions no change in reduced reflex time could be demonstrated.

R. Y. Herren

1933-01-01

119

Blockade of toll-like receptor 4 attenuates morphine tolerance and facilitates the pain relieving properties of morphine.  

PubMed

The ventrolateral periaqueductal gray (vlPAG) is an integral locus for morphine action. Although it is clear that glia contribute to the development of morphine tolerance, to date, the investigation of their role has been limited to spinal and medullary loci. Opioids induce a neuroinflammatory response that opposes acute and long-term analgesia, thereby limiting their efficacy as therapeutic agents. Recent data suggest that the innate immune receptor Toll-like receptor 4 (TLR4), along with its coreceptor myeloid differentiation factor-2 (MD-2), mediates these effects. To date, the brain loci through which TLR4 modulates morphine tolerance have not been identified. We have previously demonstrated that chronic subcutaneous morphine results in tolerance that is accompanied by increases in vlPAG glial cell activity. Using in vivo pharmacological manipulations of vlPAG glia and TLR4 in the adult male rat, we show that intra-vlPAG administration of the general glial cell metabolic inhibitor propentofylline or the astrocyte activity inhibitor fluorocitrate attenuate tolerance to morphine. Characterization of MD-2 expression within the PAG revealed dense MD-2 expression throughout the vlPAG. Further, antagonizing vlPAG TLR4 dose dependently prevented the development of morphine tolerance, and vlPAG microinjections of TLR4 agonists dose dependently produced a "naive" tolerance to subsequent challenge doses of morphine. Finally, using a model of persistent inflammatory pain and pharmacological manipulation of TLR4 we demonstrate that systemic antagonism of TLR4 potentiated acute morphine antihyperalgesia. These results, together, indicate that vlPAG glia regulate morphine tolerance development via TLR4 signaling, and implicate TLR4 as a potential therapeutic target for the treatment of pain. PMID:24089500

Eidson, Lori N; Murphy, Anne Z

2013-10-01

120

Efficacy and tolerability of celecoxib versus hydrocodone\\/acetaminophen in the treatment of pain after ambulatory orthopedic surgery in adults  

Microsoft Academic Search

Background: Current outpatient management of postoperative pain includes the use of oral opioid analgesics or nonsteroidal anti-inflammatory drugs; however, both types of medications are associated with side effects that can limit their usefulness in the outpatient setting.Objective: Two studies with identical protocols assessed the single- and multiple-dose analgesic efficacy and tolerability of celecoxib, a specific cyclooxygenase-2 inhibitor, in the treatment

Joseph S. Gimbel; Andrew Brugger; William Zhao; Kenneth M. Verburg; G. Steven Geis

2001-01-01

121

Impact of opioid rescue medication for breakthrough pain on the efficacy and tolerability of long-acting opioids in patients with chronic non-malignant pain  

PubMed Central

Background There is little evidence that short-acting opioids as rescue medication for breakthrough pain is an optimal long-term treatment strategy in chronic non-malignant pain. We compared clinical studies of long-acting opioids that allowed short-acting opioid rescue medication with those that did not, to determine the impact of opioid rescue medication use on the analgesic efficacy and tolerability of chronic opioid therapy in patients with chronic non-malignant pain. Methods We searched MEDLINE (1950 to July 2006) and EMBASE (1974 to July 2006) using terms for chronic non-malignant pain and long-acting opioids. Independent review of the search results identified 48 studies that met the study selection criteria. The effect of opioid rescue medication on analgesic efficacy and the incidence of common opioid-related side-effects were analysed using meta-regression. Results After adjusting for potentially confounding variables (study design and type of opioid), the difference in analgesic efficacy between the ‘rescue’ and the ‘no rescue’ studies was not significant, with regression coefficients close to 0 and 95% confidence intervals that excluded an effect of more than 18 points on a 0–100 scale in each case. There was also no significant difference between the ‘rescue’ and the ‘no rescue’ studies for the incidence of nausea, constipation, or somnolence in both the unadjusted and the adjusted analyses. Conclusions We found no evidence that rescue medication with short-acting opioids for breakthrough pain affects analgesic efficacy of long-acting opioids or the incidence of common opioid-related side-effects among chronic non-malignant pain patients.

Devulder, J.; Jacobs, A.; Richarz, U.; Wiggett, H.

2009-01-01

122

Effect of Transcutaneous Electrical Nerve Stimulation on Sensation Thresholds in Patients with Painful Diabetic Neuropathy: An Observational Study  

ERIC Educational Resources Information Center

|Transcutaneous electrical nerve stimulation (TENS) is one of the therapies for painful neuropathy. Its analgesic mechanisms probably involve the gate control theory, the physiological block and the endogenous pain inhibitory system. The aim of the study was to determine whether TENS improves small fibre function diminished because of painful

Moharic, Metka

2010-01-01

123

Perception, Drug Preference, and Pain Tolerance in Drug Users. Executive Summary.  

National Technical Information Service (NTIS)

The objective of the research was to develop an understanding of the experience of pain for drug abusers. It was posited that their perceptual style predicts their pain experience as well as their drug of choice. Utilizing a descriptive survey design, rel...

M. A. Compton

1993-01-01

124

Cortisol reduces recall of explicit contextual pain memory in healthy young men.  

PubMed

Remembering painful incidents has important adaptive value but may also contribute to clinical symptoms of posttraumatic stress disorder and chronic pain states. Because glucocorticoids are known to impair memory retrieval processes, we investigated whether cortisol affects recall of previously experienced pain in healthy young men. In a double-blind, placebo-controlled crossover study, 20 male participants were presented pictures, half of them combined with a heat-pain stimulus. The next day, the same pictures were shown in the absence of pain. Cortisol (20 mg) administered 1h before retention testing reduced recall of explicit contextual pain memory, whereas it did not affect pain threshold or pain tolerance. PMID:20211530

Schwegler, Kyrill; Ettlin, Dominik; Buser, Iris; Klaghofer, Richard; Goetzmann, Lutz; Buddeberg, Claus; Alon, Eli; Brügger, Mike; de Quervain, Dominique J-F

2010-03-07

125

Effect of a single 30?min UMTS mobile phone-like exposure on the thermal pain threshold of young healthy volunteers.  

PubMed

One of the most frequently investigated effects of radiofrequency electromagnetic fields (RF EMFs) on the behavior of complex biological systems is pain sensitivity. Despite the growing body of evidence of EMF-induced changes in pain sensation, there is no currently accepted experimental protocol for such provocation studies for the healthy human population. In the present study, therefore, we tested the effects of third generation Universal Mobile Telecommunications System (UMTS) RF EMF exposure on the thermal pain threshold (TPT) measured on the surface of the fingers of 20 young adult volunteers. The protocol was initially validated with a topical capsaicin treatment. The exposure time was 30?min and the genuine (or sham) signal was applied to the head through a patch antenna, where RF EMF specific absorption rate (SAR) values were controlled and kept constant at a level of 1.75?W/kg. Data were obtained using randomized, placebo-controlled trials in a double-blind manner. Subjective pain ratings were tested blockwise on a visual analogue rating scale (VAS). Compared to the control and sham conditions, the results provide evidence for intact TPT but a reduced desensitization effect between repeated stimulations within the individual blocks of trials, observable only on the contralateral side for the genuine UMTS exposure. Subjective pain perception (VAS) data indicated marginally decreased overall pain ratings in the genuine exposure condition only. The present results provide pioneering information about human pain sensation in relation to RF EMF exposure and thus may contribute to cover the existing gap between safety research and applied biomedical science targeting the potential biological effects of environmental RF EMFs. Bioelectromagnetics. 34:530-541. © 2013 Wiley Periodicals, Inc. PMID:23787775

Vecsei, Zsuzsanna; Csathó, Arpád; Thuróczy, György; Hernádi, István

2013-06-20

126

The MERITO Study: a multicentre trial of the analgesic effect and tolerability of normal-release oral morphine during 'titration phase' in patients with cancer pain.  

PubMed

Adequate and rapid pain control is one of the main goals of cancer pain treatment. The objective of this study was to assess the effect and tolerability of oral normal-release morphine during the initial phase of treatment in patients with moderate-to-severe cancer pain. Consecutive patients naïve to strong opioids received normal-release morphine 5 or 10 mg every 4 h during the titration phase (first 5 days), depending on previous analgesic therapy. Pain intensity was assessed using an 11-point Numerical Rating Scale (0-10), and data were recorded in a patient-compiled diary. The primary endpoint was the proportion of time with pain control (a reduction of at least 50% with respect to the baseline pain score) during the titration phase. A total of 159 consecutive patients (102 men; mean age 65 years) with cancer-related pain were enrolled. Pain control was observed for 75% (95% CI 70-80) of the follow-up period in the intent-to-treat population. Overall, 50% and 75% of patients achieved pain control within 8 and 24 h after starting normal-release morphine therapy respectively. The mean pain score was 7.63 points at baseline, and decreased to 2.43 and 1.67 points (both P<0.001) at days 3 and 5 respectively. The most commonly reported adverse events were somnolence (24% of patients), constipation (22%), vomiting (13%), nausea (10%) and confusion (7%). Normal-release morphine results in rapid and satisfactory pain control, and is well tolerated, during the strong-opioid titration phase in patients with moderate-to-severe cancer pain. PMID:18477715

De Conno, F; Ripamonti, C; Fagnoni, E; Brunelli, C; Luzzani, M; Maltoni, M; Arcuri, E; Bertetto, O

2008-04-01

127

The role of threat-expectancy in acute pain: effects on attentional bias, coping strategy effectiveness and response to pain  

Microsoft Academic Search

The aims of this study were threefold. Firstly, to investigate the effect of increasing threat-expectancy on attentional biases towards pain-related words. Secondly, to determine the interaction between threat-expectancy and the effectiveness of two coping strategies on pain threshold and tolerance. Thirdly, to investigate the relationship between fear of pain and the experimental manipulations. One hundred undergraduate psychology students were randomly

Alison Boston; Louise Sharpe

2005-01-01

128

Lack of Rapid Development of Opioid Tolerance During Alfentanil and Remifentanil Infusions for Postoperative Pain  

Microsoft Academic Search

Studies in animals and volunteers have suggested the development of acute tolerance to opioid analgesics. In this article, we present data from patients who reg- ulated their own target-controlled infusions of alfen- tanil and remifentanil to provide analgesia in the im- mediate postoperative period. Fifty-one patients received alfentanil for 24 h after cardiac surgery, and 30 patients received remifentanil for

Stefan Schraag; Matthew R. Checketts; Gavin N. C. Kenny

1999-01-01

129

Structural Health Monitoring: Leveraging Pain in the Human Body  

NASA Astrophysics Data System (ADS)

Tissue damage, or the perception thereof, is managed through pain experience. The neurobiological process of pain triggers most effective defense mechanisms for our safety. Structural health monitoring (SHM) is also a very similar function, albeit in engineering systems. SHM technology can leverage many aspects of pain mechanisms to progress in several critical areas. Discrimination between features from the undamaged and damaged structures can follow the threshold gate mechanism of the pain perception. Furthermore, the sensing mechanisms can be adaptive to changes by adjusting the threshold as does the pain perception. A distributed sensor network, often advanced by SHM, can be made fault-tolerant and robust by following the perception way of self-organization and redundancy. Data handling in real life is a huge challenge for large-scale SHM. As sensory data of pain is first cleaned, the threshold is then processed through experiential information gathering and use.

Nayak, Subhadarshi

2012-07-01

130

Altered nucleus accumbens circuitry mediates pain-induced antinociception in morphine-tolerant rats.  

PubMed

We investigated the effect of chronic administration of morphine on noxious stimulus-induced antinociception (NSIA) produced by intraplantar capsaicin injection. In the untreated (naive) rat, we previously found that NSIA depends on activation of dopamine, nicotinic acetylcholine, and mu- and delta-opioid receptors in nucleus accumbens. Rats chronically implanted with subcutaneous morphine pellets demonstrated tolerance to the antinociceptive effects of acute systemic morphine administration but did not show cross-tolerance to NSIA. Morphine pretreatment, however, significantly reduced NSIA dependence on intra-accumbens opioid receptors but not on dopamine or nicotinic acetylcholine receptors. As observed in naive rats, intra-accumbens microinjection of either the dopamine receptor antagonist flupentixol or the nicotinic receptor antagonist mecamylamine blocked NSIA in rats tolerant to the antinociceptive effects of morphine, but, in contrast to naive rats, intra-accumbens microinjection of either the mu-receptor antagonist Cys2,Tyr3,Orn5,Pen7 amide or the delta-receptor antagonist naltrindole failed to block NSIA. These findings suggest that although NSIA is dependent on nucleus accumbens opioid receptors in the naive state, this dependence disappears in rats tolerant to the antinociceptive effects of morphine, which may account for the lack of NSIA cross-tolerance. In separate experiments, intra-accumbens extracellular dopamine levels were measured using microdialysis. Dopamine levels increased after either capsaicin or systemic morphine administration in naive rats but only after capsaicin administration in morphine pretreated rats. Thus, intra-accumbens dopamine release paralleled antinociceptive responses in naive and morphine pretreated rats. PMID:12151557

Schmidt, Brian L; Tambeli, Claudia H; Barletta, Justine; Luo, Lei; Green, Paul; Levine, Jon D; Gear, Robert W

2002-08-01

131

Effects of naltrexone on electrocutaneous pain in patients with hypertension compared to normotensive individuals.  

PubMed

An opioid mechanism may help explain hypertensive hypoalgesia. A double-blind placebo-controlled design compared the effects of opioid blockade (naltrexone) and placebo on electrocutaneous pain threshold, pain tolerance, and retrospective McGill Pain Questionnaire ratings in 35 unmedicated patients with essential hypertension and 28 normotensive individuals. The hypertensives experienced less pain than normotensives during the assessment of their pain tolerance; however, this manifestation of hypertensive hypoalgesia was not moderated by naltrexone. These findings fail to support the hypothesis that essential hypertension is characterised by relative opioid insensitivity. PMID:18031920

Ring, Christopher; France, Christopher R; al'Absi, Mustafa; Edwards, Louisa; McIntyre, David; Carroll, Douglas; Martin, Una

2007-10-13

132

Neuropathic Pain Activates the Endogenous   Opioid System in Mouse Spinal Cord and Induces Opioid Receptor Tolerance  

Microsoft Academic Search

Release of endogenous dynorphin opioids within the spinal cord after partial sciatic nerve ligation (pSNL) is known to contribute to the neuropathic pain processes. Using a phosphoselective antibody ( opioid receptor (KOR-P)) able to detect the serine 369 phosphorylated form of the KOR, we determined possible sites of dynorphin action within the spinal cord after pSNL. KOR-P immunoreactivity (IR) was

Mei Xu; Michael Petraschka; Jay P. McLaughlin; Ruth E. Westenbroek; Marc G. Caron; Robert J. Lefkowitz; Traci A. Czyzyk; John E. Pintar; Gregory W. Terman; Charles Chavkin

2004-01-01

133

[BK(Ca) channel agonist NS1619 and Kv channel antagonist 4-AP on the facial mechanical pain threshold in a rat model of chronic constriction injury of the infraorbital nerve].  

PubMed

Trigeminal neuralgia is a paroxysmal disorder with severely disabling facial pain and thus continues to be a real therapeutic challenge. At present there are few effective drugs for treatment of this pain. The present study was aimed to explore the involvement of BK(Ca) channels and Kv channels in the mechanical allodynia in a rat model of trigeminal neuropathic pain. Here the effectiveness of drug target injection at the trigeminal ganglion through the infraorbital foramen was first evaluated by immunofluorescence and animal behavior test. Trigeminal neuropathic pain model was established by chronic constriction injury of the infraorbital nerve (ION-CCI) in rats. BK(Ca) channel agonist and Kv channel antagonist were administered into the trigeminal ganglion in ION-CCI rats and sham rats by the above target injection method, and the facial mechanical pain threshold was measured. The results showed that the drug could accurately reach the trigeminal ganglion by target injection which was more effective than that by the normal injection around infraorbital foramen. Rats suffered significant mechanical allodynia in the whisker pad of the operated side from 6 d to 42 d after ION-CCI. BK(Ca) channel agonist NS1619 significantly and dose-dependently attenuated the facial mechanical allodynia and increased the facial mechanical pain threshold in ION-CCI rats 15 d after operation. Kv antagonist 4-AP was able to reduce the threshold in ION-CCI rats when facial mechanical threshold was partly recovered and relatively stable on the 35th day after operation. These results suggest that BK(Ca) channel agonist NS1619 and Kv channel antagonist 4-AP can significantly affect the rats' facial mechanical pain threshold after ION-CCI. Activation of BK(Ca) channels may be related to the depression of the primary afferent neurons in trigeminal neuropathic pain pathways. Activation of Kv channels may exert a tonic inhibition on the trigeminal neuropathic pain. PMID:20945047

Liu, Cai-Yue; Li, Na; Zhao, Yun-Fu; Ma, Bei

2010-10-25

134

Pressure-pain function in desensitized and hypersensitized muscle and skin assessed by cuff algometry.  

PubMed

This study assessed a newly developed cuff pressure algometry during discrete leg skin/muscle sensitization and anesthesia. Experimental setup consisted of a pneumatic tourniquet cuff, a computer-controlled air compressor, and an electronic visual analog scale (VAS). The first experiment assessed cuff algometry before and after selective anesthesia of the skin and the muscle under the cuff. The second experiment assessed cuff algometry before and during skin and muscle sensitization with capsaicin cream and injection of capsaicin. Pressure-pain detection threshold, pressure equivalent to the pain intensity of 2 on the VAS (PVAS2), pressure-pain tolerance threshold, and pressure-pain stimulus-response (SR) function were evaluated. Local anesthesia of the muscle increased the pain thresholds significantly and shifted the average SR function to the right indicating desensitization, whereas cutaneous anesthesia did not affect the pressure thresholds and increased the slope of the SR function. Capsaicin cream did not affect pressure-pain tolerance threshold, whereas PVAS2 and the slope of the SR function were significantly decreased. Intramuscular capsaicin injection decreased the pain thresholds and did not affect the slope of the SR function. Both interventions shifted the SR function to the left. The cuff algometry reliably assessed the pressure-pain SR function during muscle sensitization/desensitization and might supplement conventional pressure algometry for standardized pressure-pain function assessment. PMID:14622851

Polianskis, Romanas; Graven-Nielsen, Thomas; Arendt-Nielsen, Lars

2002-02-01

135

Agreeable Smellers and Sensitive Neurotics - Correlations among Personality Traits and Sensory Thresholds  

PubMed Central

Correlations between personality traits and a wide range of sensory thresholds were examined. Participants (N?=?124) completed a personality inventory (NEO-FFI) and underwent assessment of olfactory, trigeminal, tactile and gustatory detection thresholds, as well as examination of trigeminal and tactile pain thresholds. Significantly enhanced odor sensitivity in socially agreeable people, significantly enhanced trigeminal sensitivity in neurotic subjects, and a tendency for enhanced pain tolerance in highly conscientious participants was revealed. It is postulated that varied sensory processing may influence an individual's perception of the environment; particularly their perception of socially relevant or potentially dangerous stimuli and thus, varied with personality.

Croy, Ilona; Springborn, Maria; Lotsch, Jorn; Johnston, Amy N. B.; Hummel, Thomas

2011-01-01

136

Effects of 50 Hz electromagnetic fields on electroencephalographic alpha activity, dental pain threshold and cardiovascular parameters in humans  

Microsoft Academic Search

Recent studies indicate that exposure to extremely low frequency magnetic fields (ELF MFs) influences human electroencephalographic (EEG) alpha activity and pain perception. In the present study we analyse the effect on electrical EEG activity in the alpha band (8–13Hz) and on nociception in 40 healthy male volunteers after 90-min exposure of the head to 50Hz ELF MFs at a flux

Sergio Ghione; Cristina Del Seppia; Lorena Mezzasalma; Luca Bonfiglio

2005-01-01

137

Application of the "threshold of toxicological concern" to derive tolerable concentrations of "non-relevant metabolites" formed from plant protection products in ground and drinking water.  

PubMed

Limits for tolerable concentrations of ground water metabolites ("non-relevant metabolites" without targeted toxicities and specific classification and labeling) derived from active ingredients (AI) of plant protection products (PPPs) are discussed in the European Union. Risk assessments for "non-relevant metabolites" need to be performed when concentrations are above 0.75 microg/L. Since oral uptake is the only relevant exposure pathway for "non-relevant metabolites", risk assessment approaches as used for other chemicals with predominantly oral exposure in humans are applicable. The concept of "thresholds of toxicological concern" (TTC) defines tolerable dietary intakes for chemicals without toxicity data and is widely applied to chemicals present in food in low concentrations such as flavorings. Based on a statistical evaluation of the results of many toxicity studies and considerations of chemical structures, the TTC concept derives a maximum daily oral intake without concern of 90 microg/person/day for non-genotoxic chemicals, even for those with appreciable toxicity. When using the typical exposure assessment for drinking water contaminants (consumption of 2L of drinking water/person/day, allocation of 10% of the tolerable daily intake to drinking water), a TTC-based upper concentration limit of 4.5 microg/L for "non-relevant metabolites" in ground/drinking water is delineated. In the present publication it has been evaluated, whether this value would cover all relevant toxicities (repeated dose, reproductive and developmental, and immune effects). Taking into account, that after evaluation of specific reproduction toxicity data from chemicals and pharmaceuticals, a value of 1 microg/kgbw/day has been assessed as to cover developmental and reproduction toxicity, a TTC value of 60 microg/person/day was assessed as to represent a safe value. Based on these reasonable worst case assumptions, a TTC-derived threshold of 3 microg/L in drinking water is derived. When a non-relevant metabolite is present in concentration below 3 microg/L, animal testing for toxicity is not considered necessary for a compound-specific risk assessment since the application of the TTC covers all relevant toxicities to be considered in such assessment and any health risk resulting from these exposures is very low. PMID:19766683

Melching-Kollmuss, Stephanie; Dekant, Wolfgang; Kalberlah, Fritz

2009-09-18

138

Bedside Testing for Chronic Pelvic Pain: Discriminating Visceral from Somatic Pain  

PubMed Central

Objectives. This study was done to evaluate three bedside tests in discriminating visceral pain from somatic pain among women with chronic pelvic pain. Study Design. The study was an exploratory cross-sectional evaluation of 81 women with chronic pelvic pain of 6 or more months' duration. Tests included abdominal cutaneous allodynia (aCA), perineal cutaneous allodynia (pCA), abdominal and perineal myofascial trigger points (aMFTP) and (pMFTP), and reduced pain thresholds (RPTs). Results. Eighty-one women were recruited, and all women provided informed consent. There were 62 women with apparent visceral pain and 19 with apparent somatic sources of pain. The positive predictive values for pelvic visceral disease were aCA-93%, pCA-91%, aMFTP-93%, pMFTP-81%, and RPT-79%. The likelihood ratio (+) and 95% C.I. for the detection of visceral sources of pain were aCA-4.19 (1.46, 12.0), pCA-2.91 (1.19, 7.11), aMTRP-4.19 (1.46, 12.0), pMFTP-1.35 (0.86, 2.13), and RPT-1.14 (0.85, 1.52), respectively. Conclusions. Tests of cutaneous allodynia, myofascial trigger points, and reduced pain thresholds are easily applied and well tolerated. The tests for cutaneous allodynia appear to have the greatest likelihood of identifying a visceral source of pain compared to somatic sources of pain.

Jarrell, John; Giamberardino, Maria Adele; Robert, Magali; Nasr-Esfahani, Maryam

2011-01-01

139

Sex Differences in Experimental and Clinical Pain Sensitivity for Patients with Shoulder Pain  

PubMed Central

Previous research demonstrates that men and women differ in the way that they perceive and process pain. Much of this work has been done in healthy adults with a lack of consensus in clinical pain populations. The purpose of this study was to investigate how men and women with shoulder pain differ in their experience of experimental and clinical pain and whether psychological processes differentially affect these responses. Fifty nine consecutive subjects (24 women, 35 men) seeking operative treatment for shoulder pain were enrolled in this study. Subjects completed self report questionnaires to assess clinical pain, catastrophizing, anxiety and depression and underwent a series of experimental pain tests consisting of pressure pain, thermal pain (threshold and tolerance), and thermal temporal summation. Results indicated that women experienced greater clinical pain and enhanced sensitivity to pressure pain. Age did not affect the observed sex differences. There were no sex differences in psychological association with experimental and clinical pain in this cohort. The relationship between clinical and experimental pressure pain was stronger in women as compared to men. These findings offer insight into the interactions between biological and psychosocial influences of pain and how these interactions vary by sex.

Kindler, Lindsay L.; Valencia, Carolina; Fillingim, Roger B.; George, Steven Z.

2010-01-01

140

Sex differences and hormonal modulation of deep tissue pain.  

PubMed

Women disproportionately suffer from many deep tissue pain conditions. Experimental studies show that women have lower pain thresholds, higher pain ratings and less tolerance to a range of painful stimuli. Most clinical and epidemiological reports suggest female gonadal hormones modulate pain for some, but not all, conditions. Similarly, animal studies support greater nociceptive sensitivity in females in many deep tissue pain models. Gonadal hormones modulate responses in primary afferents, dorsal horn neurons and supraspinal sites, but the direction of modulation is variable. This review will examine sex differences in deep tissue pain in humans and animals focusing on the role of gonadal hormones (mainly estradiol) as an underlying component of the modulation of pain sensitivity. PMID:23872333

Traub, Richard J; Ji, Yaping

2013-07-17

141

Effects of unpredictable stimulation on pain and nociception across the cardiac cycle.  

PubMed

Previous research has demonstrated that the nociceptive flexion reflex (NFR) and pain-related evoked potentials are reduced in amplitude when elicited during the middle of the cardiac cycle. Despite these findings, suggesting a baroreceptor mechanism of antinociception during systole, pain intensity ratings reported in these studies were not modulated across the cardiac cycle. This discrepancy between the neurophysiological correlates of pain and its subjective experience was the focus of the current study that used a mixed block design to assess the effects of natural arterial baroreceptor activity on both the NFR and pain intensity and unpleasantness reports. Specifically, electrocutaneous stimuli were randomly delivered to the sural nerve at one of five intensities (50% pain threshold, 75% pain threshold, pain threshold, midway between pain threshold and pain tolerance, pain tolerance) at five intervals (0, 150, 300, 450, and 600ms) after the R-wave of the electrocardiogram. Under painful stimulation, intensity and unpleasantness varied in a quadratic manner across the cardiac cycle; pain was highest at R+300ms and lowest at R+0 and R+600ms. Under non-painful stimulation, ratings declined linearly as the cycle progressed. Finally, nociceptive responses did not differ among the R-wave to stimulation intervals for both painful and non-painful intensities. The observed phasic modulation of pain may be explained by a central nervous system alarm/defence reaction triggered by the unpredictability of the potentially damaging stimulation. The absence of systolic attenuation of nociceptive responding is compatible with previous evidence that baroreceptor modulation of the NFR is abolished under conditions of heightened arousal. PMID:19766395

Martins, Amadeu Quelhas; Ring, Christopher; McIntyre, David; Edwards, Louisa; Martin, Una

2009-09-18

142

Pain Sensitivity Risk Factors for Chronic TMD: Descriptive Data and Empirically Identified Domains from the OPPERA Case Control Study  

PubMed Central

Many studies report that people with temporomandibular disorders (TMD) are more sensitive to experimental pain stimuli than TMD-free controls. Such differences in sensitivity are observed in remote body sites as well as in the orofacial region, suggesting a generalized upregulation of nociceptive processing in TMD cases. This large case-control study of 185 adults with TMD and 1,633 TMD-free controls measured sensitivity to painful pressure, mechanical cutaneous, and heat stimuli, using multiple testing protocols. Based on an unprecedented 36 experimental pain measures, 28 showed statistically significantly greater pain sensitivity in TMD cases than controls. The largest effects were seen for pressure pain thresholds at multiple body sites and cutaneous mechanical pain threshold. The other mechanical cutaneous pain measures and many of the heat pain measures showed significant differences, but with lesser effect sizes. Principal component analysis (PCA) of the pain measures derived from 1,633 controls identified five components labeled: (1) heat pain ratings, (2) heat pain aftersensations and tolerance, (3) mechanical cutaneous pain sensitivity, (4) pressure pain thresholds, and (5) heat pain temporal summation. These results demonstrate that, compared to TMD-free controls, chronic TMD cases are more sensitive to many experimental noxious stimuli at extra-cranial body sites, and provides for the first time the ability to directly compare the case-control effect sizes of a wide range of pain sensitivity measures.

Greenspan, Joel D.; Slade, Gary D.; Bair, Eric; Dubner, Ronald; Fillingim, Roger B.; Ohrbach, Richard; Knott, Charlie; Mulkey, Flora; Rothwell, Rebecca; Maixner, William

2011-01-01

143

Efficacy, safety, and tolerability of fulranumab, an anti-nerve growth factor antibody, in the treatment of patients with moderate to severe osteoarthritis pain.  

PubMed

Nerve growth factor (NGF) is increased in chronic pain conditions. This study examined analgesic efficacy and safety of fulranumab, a fully human monoclonal anti-NGF antibody, in adults with chronic osteoarthritis pain. Patients (n=466, intent-to-treat) were randomized to receive, in addition to their current pain therapy, subcutaneous injections in 1 of 6 parallel treatment groups: placebo (n=78), fulranumab 1mg (n=77) or 3mg (n=79) every 4weeks (Q4wk), 3mg (n=76), 6mg (n=78), or 10mg (n=78) every 8weeks (Q8wk). Primary efficacy results showed that fulranumab significantly reduced the average pain intensity score (P?0.030) from baseline to week 12 compared with placebo in the 3mgQ4wk, 6mgQ8wk, and 10mgQ8wk groups. Secondary efficacy outcomes indicated that significant improvement occurred compared with placebo at week 12 on the Western Ontario and McMaster Universities Osteoarthritis Index subscales of pain, stiffness, and physical function (P<0.040) across all fulranumab groups except 1mgQ4wk, on the Brief Pain Inventory-Short Form subscales of pain intensity (P?0.016) and pain interference (P?0.030) in the 3mgQ4wk and 10mgQ8wk groups, and on the Patient Global Assessment score (P?0.040) in the 3mgQ4wk, 6mgQ8wk, and 10mgQ8wk groups. The most common (?5% of patients) treatment-emergent adverse events in overall fulranumab groups during the first 12weeks included paresthesia (7%), headache (5%), and nasopharyngitis (5%). Most neurologic-related treatment-emergent adverse events were mild or moderate and resolved at the end of week 12. Serious adverse events occurred in 3 patients, but they were not neurologically related and resolved before study completion. Fulranumab treatment resulted in statistically significant efficacy in pain measures and physical function versus placebo and was generally well tolerated. PMID:23748114

Sanga, Panna; Katz, Nathaniel; Polverejan, Elena; Wang, Steven; Kelly, Kathleen M; Haeussler, Juergen; Thipphawong, John

2013-06-05

144

Fentanyl Buccal Tablets for Breakthrough Pain in Highly Tolerant Cancer Patients: Preliminary Data on the Proportionality Between Breakthrough Pain Dose and Background Dose  

Microsoft Academic Search

ContextCancer patients receiving high doses of opioids as background medication are challenging, and it would be useful clinically to know whether a rapid-onset opioid (ROO) for breakthrough cancer pain (BTcP) may be started at a dose proportional to the background opioid dose.

Sebastiano Mercadante; Patrizia Ferrera; Claudio Adile; Alessandra Casuccio

2011-01-01

145

Effect of Sub-maximal Exercise Stress on Cold Pressor Pain: A Gender Based Study.  

PubMed

Background Analgesic effect of exercise is a well established fact; however available reports are contradictory on gender differences in pain perception following exercise stress test. Objective The current study is prospectively designed to evaluate and compare the effect of acute bout of sub-maximal exercise stress on cold pressor pain in normal adult males and females. Method The experimental study design involved healthy adults (n= 41); females (n = 18) and males (n=23) aged between 18 to 25 years and included them into four sets of experiments: SET I (Control), "resting blood pressure, radial pulse and respiratory rate were recorded after 15 minutes of complete supine relaxation. SET II (Cold Pressor Pain Test): Pain Threshold, Pain Tolerance, and Pain Duration in seconds were taken. SET III (Exercise Stress Test): Sub-maximal exercise of 70 to 75% of maximum predicted heart rate was given for 6 minutes. SET IV (Cold Pressor Pain Test immediately after Exercise Stress Test): At 0 minute of recovery again the pain parameters; Pain Threshold, Pain Tolerance, and Pain Duration in seconds were taken. SET I, SET II were performed in order on the first day and SET III and SET IV on the second day to ensure only a single Cold Pressor Pain Test is performed in each day. Result The data (Mean +/= SD) analysis showed significant increased in pain threshold (males: 14.36 +/= 10.6 Vs 21.47 +/= 13seconds, p< 0.001, females: 14.1 +/= 11.5 Vs 23.81 +/= 20.22 seconds, p<0.001) and pain tolerance time (males: 41.3 +/= 19.31Vs 54.1 +/= 21.7 seconds, p<0.001) in both sexes after 6 min of acute bout of sub-maximal exercise stress test with comparable age, BMI and baseline resting values of pain parameters and pulse rate and blood pressure. The percentage increment pain tolerance time following the exercise stress in female is higher than male (78.6 Vs 68.9%). Conclusion The result suggests that pain sensation decreases immediately after a brief period of exercise challenge irrespective of gender, and the analgesic effect of the acute bout of exercise in terms of pain tolerant time is more enhanced in females than males. PMID:23774415

Pokhrel, B R; Malik, S L; Ansari, A H; Paudel, B H; Sinha, R; Sinha, M

146

The Measurement of Suprathreshold Pain.  

National Technical Information Service (NTIS)

The study of both subjective and physiological responses to painful stimulation is fraught with a number of difficulties, one of which is the difference in functional relationships between the threshold and suprathreshold of pain, such as surgical pain. B...

J. Voevodsky L. M. Cooper A. H. Morgan E. R. Hilgard

1967-01-01

147

Painful and non-painful pressure sensations from human skeletal muscle.  

PubMed

Painful and non-painful pressure sensations from muscle are generally accepted to exist but the peripheral neural correlate has not been clarified. The aim of the present human study was to assess the non-painful and painful pressure sensitivity with (1) anaesthetised skin, and (2) anaesthetised skin combined with a block of large diameter muscle afferents. The skin was anaesthetised by a topically applied anaesthetic cream and later lidocaine was administrated subcutaneously. The pressure sensitivity was assessed quantitatively by computer-controlled pressure stimulation on the anterior tibial muscle. Thresholds to detection, pain and pain tolerance were assessed. In the first experiment, computer-controlled needle insertion depths evoking touch and pain sensations were used to assess the efficacy of cutaneous anaesthesia. Touch and pain sensations evoked during needle insertions were found to be superficial in intact skin but when anaesthetised, touch sensation was occasionally evoked at depths related to penetration of the fascia. With the skin completely anaesthetised to brush and von Frey hair pinprick stimulation, skin indentation with the strongest von Frey hair caused a sensation described as a deep touch sensation. Simultaneously, pressure detection and pain thresholds increased but it was still possible to elicit non-painful and painful pressure sensation in all subjects. In a second experiment, a differential nerve block of group I and II afferent fibres was obtained by full-leg ischaemia simultaneously with cutaneous anaesthesia. The efficacy of the tourniquet block was continuously assessed by a battery of somatosensory tests (heat, brush, vibration, electrical and movement detection) applied at the foot simultaneously with pressure stimulation on the anterior tibial muscle. After 20 min of ischaemia, group II afferent fibres mediating the sensations of movement detection, vibration and brush on the foot was blocked but the heat pain threshold was not affected. In this condition (anaesthetised skin and block of group I and II fibres from deep tissue) a pressure sensation was evoked in 70% of subjects although the pressure detection threshold was increased. The pressure pain sensitivity was decreased, which, however, might indicate a partial block of group III and IV muscle afferents. In a third experiment, the tactile sensations elicited by electrical stimulation of the tibialis anterior muscle and skin at the lower leg were significantly decreased after 20 min of ischaemia, validating the blocking effects of group I and II nerve fibres. The present data show a marginal contribution of cutaneous afferents to the pressure pain sensation that, however, is relatively more dependent on contributions from deep tissue group III and IV afferents. Moreover, a pressure sensation can be elicited from deep tissue probably mediated by group III and IV afferents involving low-threshold mechanoreceptors. PMID:15480607

Graven-Nielsen, Thomas; Mense, Siegfried; Arendt-Nielsen, Lars

2004-10-12

148

Modulation of Remifentanil-Induced Analgesia, Hyperalgesia, and Tolerance by Small-Dose Ketamine in Humans  

Microsoft Academic Search

Adding a small dose of ketamine to opioids may increase the analgesic effect and prevent opioid-induced hyperal- gesia and acute tolerance to opioids. In this randomized, double-blinded, placebo-controlled crossover study, we investigated the effect of remifentanil combined with small concentrations of ketamine on different experimen- tal pain models. Pain detection thresholds to single and repeated IM electrical stimulation and to

Andrea Gerber; Thomas W. Schnider; Steen Petersen-Felix; Lars Arendt-Nielsen; Michele Curatolo

2003-01-01

149

Multi-Threshold Threshold Elements  

Microsoft Academic Search

A multi-threshold element is one in which several thresholds are used to separate the true inputs from the false inputs. Many circuit elements and configurations can be described by this model. An approach, based on conventional single-threshold threshold elements, is developed for the analysis and synthesis of multithreshold threshold elements. It is shown that the basic properties of such elements

Donald R. Haring

1966-01-01

150

Restricted environmental stimulation and the enhancement of hypnotizability: Pain, EEG alpha, skin conductance and temperature responses  

Microsoft Academic Search

Restricted environmental stimulation procedures were used with 10 Ss. The Stanford Hypnotic Clinical Scale: Adult (SHCS) of Morgan and J. R. Hilgard (1975), modified to include a posthypnotic suggestion for an analgesic reaction, and pain threshold and tolerance tests were administered prior to restricted environmental stimulation technique (REST), immediately after REST, and 10–14 days later. Occipital EEG alpha, skin conductance,

Arreed F. Barabasz

1982-01-01

151

The hypoalgesic effect of imipramine in different human experimental pain models  

Microsoft Academic Search

In a randomized, placebo-controlled, double-blind, cross-over study, the hypoalgesic effect of a single oral dose of 100 mg imipramine was investigated in 12 healthy volunteers. Test procedures performed before, 3, 6, and 9 h after medication included determination of (1) pain detection and tolerance thresholds to heat and pressure; (2) the thresholds of quadriceps femoris muscle withdrawal reflex to single

Lars Poulsen; Lars Arendt-Nielsen; Kim Brøsen; Karin K. Nielsen; Lars F. Gram

1995-01-01

152

Nitrous oxide analgesia in humans: Acute and chronic tolerance  

PubMed Central

Electrical tooth stimulation was used to investigate whether humans develop tolerance to nitrous oxide (N2O) analgesia within a single administration as well as over repeated administrations. In a double-blind cross-over experiment, 77 subjects received a 40-minute administration of 38% N2O at one session and placebo gas at the other. The sessions were separated by 1 week and the order of gas administration was counterbalanced. Acute analgesic tolerance developed for pain threshold but not for detection threshold. There was no evidence of a hyperalgesic rebound effect following cessation of the N2O administration. In a second double-blind experiment, 64 subjects received both 30-min of placebo gas and 30-min of 35% N2O, separated by a 35-min gas wash-out period, during each of 5 sessions. Sensory thresholds were assessed prior to drug or placebo administration (baseline) and between 7-12 min and 25-30 min of gas administration. A control group of 16 subjects received only placebo gas at these 5 sessions. During a sixth session, the experimental procedures were similar to the previous sessions except that the control group received N2O for the first time and the experimental group was sub-divided to test for conditioned drug effects. For both detection and pain threshold measures, acute tolerance developed during the initial N2O exposure and chronic tolerance developed over repeated administrations. Although chronic tolerance developed, a test for Pavlovian drug conditioning found no evidence of conditioned effects on sensory thresholds. In conclusion, acute and chronic tolerance develop to N2O’s analgesic effects in humans.

Ramsay, Douglas S.; Leroux, Brian G.; Rothen, Marilynn; Prall, Christopher W.; Fiset, Louis O.; Woods, Stephen C.

2006-01-01

153

The plasticity of the association between mu-opioid receptor and glutamate ionotropic receptor N in opioid analgesic tolerance and neuropathic pain.  

PubMed

Multiple groups have reported the functional cross-regulation between mu-opioid (MOP) receptor and glutamate ionotropic receptor N (GluN), and the post-synaptic association of these receptors has been implicated in the transmission and modulation of nociceptive signals. Opioids, such as morphine, disrupt the MOP receptor-GluN receptor complex to stimulate the activity of GluN receptors via protein kinase C (PKC)/Src. This increased GluN receptor activity opposes MOP receptor signalling, and via neural nitric oxide synthase (nNOS) and calcium and calmodulin regulated kinase II (CaMKII) induces the phosphorylation and uncoupling of the opioid receptor, which results in the development of morphine analgesic tolerance. Both experimental in vivo activation of GluN receptors and neuropathic pain separate the MOP receptor-GluN receptor complex via protein kinase A (PKA) and reduce the analgesic capacity of morphine. The histidine triad nucleotide-binding protein 1 (HINT1) associates with the MOP receptor C-terminus and connects the activities of MOP receptor and GluN receptor. In HINT1((-/-)) mice, morphine promotes enhanced analgesia and produces tolerance that is not related to GluN receptor activity. In these mice, the GluN receptor agonist N-methyl-d-aspartate acid (NMDA) does not antagonise the analgesic effects of morphine. Treatments that rescue morphine from analgesic tolerance, such as GluN receptor antagonism or PKC, nNOS and CaMKII inhibitors, all induce MOP receptor-GluN receptor re-association and reduce GluN receptor/CaMKII activity. In mice treated with NMDA or suffering from neuropathic pain (induced by chronic constriction injury, CCI), GluN receptor antagonists, PKA inhibitors or certain antidepressants also diminish CaMKII activity and restore the MOP receptor-GluN receptor association. Thus, the HINT1 protein stabilises the association between MOP receptor and GluN receptor, necessary for the analgesic efficacy of morphine, and this coupling is reduced following the activation of GluN receptors, similar to what is observed in neuropathic pain. PMID:23499699

Sánchez-Blázquez, Pilar; Rodríguez-Muñoz, Maria; Berrocoso, Esther; Garzón, Javier

2013-03-13

154

Pain site and the effects of amputation pain: further clarification of the meaning of mild, moderate, and severe pain  

Microsoft Academic Search

Research among persons with cancer pain suggests that the association between pain intensity and pain interference is non-linear. That is, pain begins to have a serious impact on functioning when it reaches a certain threshold level (about 5 on 0–10 scales). Often, a second pain threshold can be identified which, once reached, shows an even greater proportional negative impact on

Mark P Jensen; Douglas G Smith; Dawn M Ehde; Lawrence R Robinsin

2001-01-01

155

Predicting pain and pain responses to opioids  

Microsoft Academic Search

The mechanisms behind the wide individual variability in pain experience and relief are an area of intense research activity. Predicting individual clinical pain and the responsiveness to analgesics should increase the efficacy and tolerability of analgesic treatments, and improve the overall treatment outcome. Several factors have shown validity in the prediction of pain, with most studies having been performed in

Clive H. Wilder-Smith

2007-01-01

156

Comparison of analgesic effects and patient tolerability of nabilone and dihydrocodeine for chronic neuropathic pain: randomised, crossover, double blind study  

PubMed Central

Objective To compare the analgesic efficacy and side effects of the synthetic cannabinoid nabilone with those of the weak opioid dihydrocodeine for chronic neuropathic pain. Design Randomised, double blind, crossover trial of 14 weeks’ duration comparing dihydrocodeine and nabilone. Setting Outpatient units of three hospitals in the United Kingdom. Participants 96 patients with chronic neuropathic pain, aged 23-84 years. Main outcome measures The primary outcome was difference between nabilone and dihydrocodeine in pain, as measured by the mean visual analogue score computed over the last 2 weeks of each treatment period. Secondary outcomes were changes in mood, quality of life, sleep, and psychometric function. Side effects were measured by a questionnaire. Intervention Patients received a maximum daily dose of 240 mg dihydrocodeine or 2 mg nabilone at the end of each escalating treatment period of 6 weeks. Treatment periods were separated by a 2 week washout period. Results Mean baseline visual analogue score was 69.6 mm (range 29.4-95.2) on a 0-100 mm scale. 73 patients were included in the available case analysis and 64 patients in the per protocol analysis. The mean score was 6.0 mm longer for nabilone than for dihydrocodeine (95% confidence interval 1.4 to 10.5) in the available case analysis and 5.6 mm (10.3 to 0.8) in the per protocol analysis. Side effects were more frequent with nabilone. Conclusion Dihydrocodeine provided better pain relief than the synthetic cannabinoid nabilone and had slightly fewer side effects, although no major adverse events occurred for either drug. Trial registration Current Controlled Trials ISRCTN15330757.

2008-01-01

157

[Psychological, emotional, spiritual and social aspects of pain].  

PubMed

We are used to speak about the organic pain origin. Meanwhile in actual and old definitions of pain the other determinants, besides the organic one, are included. They are changing the pain threshold and the pain tolerance. Dame Cicely Saunders, who started the modern hospice movement of care for those in advanced stage of disease, describes the concept of "total pain" as involving organic, emotional, spiritual and social determinants. Such pain concept fits into the classical division of pain pathogenesis. The basic forms are: nociceptive, neuropathic and according to the old nomenclature psychogenic. The first one is defense reaction, the second one is due to pathology. The third one is very complex and this article is dealing with it. The patient's emotional reactions, especially the fear and anxiousness producing tension increase the pain. Therefore, different kinds of relaxation or attention distraction can help a lot in relieving the pain. Spiritual pain can be a very difficult symptom increasing the physical pain significantly. Everybody has spiritual needs and they are independent of religious orientation. The experience of life's and suffering's senslessness, personal valulessness and situational hopelessness lowers significantly pain tolerance. The selfconfidence, the confidence in other persons, in somebody over us has the opposite effect. And finally the pain is often easier to cope with in the presence of a friendly person. To be able to complain and to describe one's own fears, especially in connection with the significance of the actual pain, helps a lot. The support of the wider community also helps. We ought to approach the patient holistically, that means also observe the person, the human being suffering, hoping and wishing to be heard, and not to be left alone. PMID:11379199

Jusi?, A

158

Bedside testing for chronic pelvic pain: discriminating visceral from somatic pain.  

PubMed

Objectives. This study was done to evaluate three bedside tests in discriminating visceral pain from somatic pain among women with chronic pelvic pain. Study Design. The study was an exploratory cross-sectional evaluation of 81 women with chronic pelvic pain of 6 or more months' duration. Tests included abdominal cutaneous allodynia (aCA), perineal cutaneous allodynia (pCA), abdominal and perineal myofascial trigger points (aMFTP) and (pMFTP), and reduced pain thresholds (RPTs). Results. Eighty-one women were recruited, and all women provided informed consent. There were 62 women with apparent visceral pain and 19 with apparent somatic sources of pain. The positive predictive values for pelvic visceral disease were aCA-93%, pCA-91%, aMFTP-93%, pMFTP-81%, and RPT-79%. The likelihood ratio (+) and 95% C.I. for the detection of visceral sources of pain were aCA-4.19 (1.46, 12.0), pCA-2.91 (1.19, 7.11), aMTRP-4.19 (1.46, 12.0), pMFTP-1.35 (0.86, 2.13), and RPT-1.14 (0.85, 1.52), respectively. Conclusions. Tests of cutaneous allodynia, myofascial trigger points, and reduced pain thresholds are easily applied and well tolerated. The tests for cutaneous allodynia appear to have the greatest likelihood of identifying a visceral source of pain compared to somatic sources of pain. PMID:22135736

Jarrell, John; Giamberardino, Maria Adele; Robert, Magali; Nasr-Esfahani, Maryam

2011-11-03

159

Reference values of mechanical and thermal pain tests in a pain-free population.  

PubMed

Quantitative sensory tests are widely used in human research to evaluate the effect of analgesics and explore altered pain mechanisms, such as central sensitization. In order to apply these tests in clinical practice, knowledge of reference values is essential. The aim of this study was to determine the reference values of pain thresholds for mechanical and thermal stimuli, as well as withdrawal time for the cold pressor test in 300 pain-free subjects. Pain detection and pain tolerance thresholds to pressure, heat and cold were determined at three body sites: (1) lower back, (2) suprascapular region and (3) second toe (for pressure) or the lateral aspect of the leg (for heat and cold). The influences of gender, age, height, weight, body-mass index (BMI), body side of testing, depression, anxiety, catastrophizing and parameters of Short-Form 36 (SF-36) were analyzed by multiple regressions. Quantile regressions were performed to define the 5th, 10th and 25th percentiles as reference values for pain hypersensitivity and the 75th, 90th and 95th percentiles as reference values for pain hyposensitivity. Gender, age and/or the interaction of age with gender were the only variables that consistently affected the pain measures. Women were more pain sensitive than men. However, the influence of gender decreased with increasing age. In conclusion, normative values of parameters related to pressure, heat and cold pain stimuli were determined. Reference values have to be stratified by body region, gender and age. The determination of these reference values will now allow the clinical application of the tests for detecting abnormal pain reactions in individual patients. PMID:20932788

Neziri, Alban Y; Scaramozzino, Pasquale; Andersen, Ole K; Dickenson, Anthony H; Arendt-Nielsen, Lars; Curatolo, Michele

2010-10-06

160

Threshold cryptosystems  

Microsoft Academic Search

Often the power to use a cryptosystem has to be shared. In threshold schemes, t-out-of-l have the power to regenerate a secret key (while less than t have not). However threshold schemes cannot be used directly in many applications, such as threshold signatures in which t-out-of-l have to co-sign a message. A normal threshold scheme would require the shareholders to

Yvo Desmedt

161

Gender role affects experimental pain responses: a systematic review with meta-analysis.  

PubMed

Gender role refers to the culturally and socially constructed meanings that describe how women and men should behave in certain situations according to feminine and masculine roles learned throughout life. The aim of this meta-analysis was to evaluate the relationship between gender role and experimental pain responses in healthy human participants. We searched computerized databases for studies published between January 1950 and May 2011 that had measured gender role in healthy human adults and pain response to noxious stimuli. Studies were entered into a meta-analysis if they calculated a correlation coefficient (r) for gender role and experimental pain. Searches yielded 4465 'hits' and 13 studies were eligible for review. Sample sizes were 67-235 participants and the proportion of female participants was 45-67%. Eight types of gender role instrument were used. Meta-analysis of six studies (406 men and 539 women) found a significant positive correlation between masculine and feminine personality traits and pain threshold and tolerance, with a small effect size (r = 0.17, p = 0.01). Meta-analysis of four studies (263 men and 297 women) found a significant negative correlation between gender stereotypes specific to pain and pain threshold and tolerance, with a moderate effect size (r = -0.41, p < 0.001). In conclusion, individuals who considered themselves more masculine and less sensitive to pain than the typical man showed higher pain thresholds and tolerances. Gender stereotypes specific to pain scales showed stronger associations with sex differences in pain sensitivity response than masculine and feminine personality trait scales. PMID:22434689

Alabas, O A; Tashani, O A; Tabasam, G; Johnson, M I

2012-03-20

162

Presence, involvement and efficacy of a virtual reality intervention on pain.  

PubMed

We explored the impact of an interactive VR environment on pain cognitions (in vivo catastrophizing and pain self-efficacy) and pain-related measures: pain threshold, pain tolerance, Pain Sensitivity Range (PSR), pain intensity and time estimation in a sample of healthy students. Sense of presence is essential to conduct a psychological treatment; if patients are not able to involve themselves in a virtual world they cannot experience relevant emotions, and the desired processes that are necessary for most psychological treatments will not occur. However, some authors argue that presence must be distinguished from the degree of engagement, involvement in the portrayed environment. The results obtained in our study are consistent with this view, since the Involvement scale of the IPQ did not correlate with any of the measures related with the treatment's efficacy. PMID:20543278

Gutierrez-Maldonado, Jose; Gutierrez-Martinez, Olga; Loreto, Desiree; Peñaloza, Claudia; Nieto, Ruben

2010-01-01

163

Gabapentin improves Cold-pressor Pain Responses in Methadone-maintained Patients  

PubMed Central

Individuals on methadone maintenance for the treatment of addiction (MM) are demonstrated to be hyperalgesic to cold-pressor pain in comparison to matched controls and ex-opioid addicts, a finding described as clinical evidence of opioid-induced hyperalgesia (OIH). Interestingly, opioids induce hyperalgesia via many of the same neuro-inflammatory and central sensitization processes that occur with the development of neuropathic pain. Evaluated in this study was the efficacy of a key pharmacotherapy for neuropathic pain, gabapentin (GPN), to reverse OIH in MM patients. Utilizing a clinical trial design and double blind conditions, changes in cold-pressor pain threshold and tolerance following a five-week trial of GPN (titrated to 2400mg/day) were evaluated at peak and trough methadone plasma levels in a well-characterized MM sample. Drug abstinence was encouraged via an escalating payment schedule, and compliance monitored via pill counts and GPN plasma levels; entered into the analyses were only those subjects compliant and abstinent throughout the study (approx 45%). Utilizing change scores from baseline, significant improvements in cold-pressor pain threshold and pain tolerance were observed at both peak and trough methadone levels (p < 0.05). Notably, drop-out rates due to medication side effects were low (2%) and the medication was well-tolerated. These results support that GPN, as prescribed for the treatment of neuropathic pain, is effective in decreasing OIH in patients who are abstinent and stable in methadone treatment.

Compton, Peggy; Kehoe, Priscilla; Sinha, Karabi; Torrington, Matt A.; Ling, Walter

2010-01-01

164

Gabapentin improves cold-pressor pain responses in methadone-maintained patients.  

PubMed

Individuals on methadone maintenance for the treatment of addiction (MM) are demonstrated to be hyperalgesic to cold-pressor pain in comparison to matched controls and ex-opioid addicts, a finding described as clinical evidence of opioid-induced hyperalgesia (OIH). Interestingly, opioids induce hyperalgesia via many of the same neuro-inflammatory and central sensitization processes that occur with the development of neuropathic pain. Evaluated in this study was the efficacy of a key pharmacotherapy for neuropathic pain, gabapentin (GPN), to reverse OIH in MM patients. Utilizing a clinical trial design and double blind conditions, changes in cold-pressor pain threshold and tolerance following a 5-week trial of GPN (titrated to 2400mg/day) were evaluated at peak and trough methadone plasma levels in a well-characterized MM sample. Drug abstinence was encouraged via an escalating payment schedule, and compliance monitored via pill counts and GPN plasma levels; entered into the analyses were only those subjects compliant and abstinent throughout the study (approximately 45%). Utilizing change scores from baseline, significant improvements in cold-pressor pain threshold and pain tolerance were observed at both peak and trough methadone levels (p<0.05). Notably, drop-out rates due to medication side effects were low (2%) and the medication was well-tolerated. These results support that GPN, as prescribed for the treatment of neuropathic pain, is effective in decreasing OIH in patients who are abstinent and stable in methadone treatment. PMID:20163921

Compton, Peggy; Kehoe, Priscilla; Sinha, Karabi; Torrington, Matt A; Ling, Walter

2010-02-16

165

Hypoalgesia Related to Elevated Resting Blood Pressure is Absent in Adolescents and Young Adults with a History of Functional Abdominal Pain  

PubMed Central

Elevated resting blood pressure (BP) is hypoalgesic in healthy individuals, but this effect is absent in adults with chronic somatic pain. This study tested whether BP-related hypoalgesia is similarly altered in individuals with a history of chronic visceral pain in childhood. Resting BP was assessed in 94 adolescents and young adults with a known history of childhood functional abdominal pain (FAP) and 55 comparable healthy controls. Responses to an acute heat pain stimulus were then evaluated following exposure to two laboratory stressors. A significant Participant Type X Systolic BP (SBP) interaction (p<.005) revealed that elevated resting SBP was associated with significantly higher heat pain threshold (p<.001) in healthy controls, but was unrelated to pain threshold in the FAP group. A similar pattern was observed for heat pain tolerance, with elevated SBP linked to significantly higher pain tolerance (p<.05) in healthy controls, but unrelated to tolerance in the FAP group. Dysfunction in BP-related hypoalgesia associated with FAP was evident regardless of whether childhood FAP had resolved or still persisted at the time of laboratory testing. Subgroup analyses indicated that BP-related hypoalgesia (in healthy controls) and FAP-linked absence of this hypoalgesia was observed only among females. Result suggest that childhood visceral chronic pain may be associated with relatively long-lasting dysfunction in overlapping systems modulating pain and BP that persists even after FAP resolves. Potential implications for later hypertension risk are discussed.

Bruehl, Stephen; Dengler-Crish, Christine M.; Smith, Craig A.; Walker, Lynn S.

2010-01-01

166

EEG responses to tonic heat pain  

Microsoft Academic Search

The aim of the present study was to characterize the EEG response pattern specific for tonic pain which is an experimental pain model resembling clinical pain more closely than phasic pain. Tonic experimental pain was produced by a series of heat pulses 1C above pain threshold over 10 min. A series of heat pulses 0.3C below pain threshold and a constant

M. T. Huber; J. Bartling; D. Pachur; S. v. Woikowsky-Biedau; S. Lautenbacher

2006-01-01

167

Application of the “threshold of toxicological concern” to derive tolerable concentrations of “non-relevant metabolites” formed from plant protection products in ground and drinking water  

Microsoft Academic Search

Limits for tolerable concentrations of ground water metabolites (“non-relevant metabolites” without targeted toxicities and specific classification and labeling) derived from active ingredients (AI) of plant protection products (PPPs) are discussed in the European Union. Risk assessments for “non-relevant metabolites” need to be performed when concentrations are above 0.75?g\\/L. Since oral uptake is the only relevant exposure pathway for “non-relevant metabolites”,

Stephanie Melching-Kollmuß; Wolfgang Dekant; Fritz Kalberlah

2010-01-01

168

Pain sensitivity and opioid analgesia: a pharmacogenomic twin study.  

PubMed

Opioids are the cornerstone medication for the management of moderate to severe pain. Unfortunately, vast inter-individual differences in dose requirements complicate their effective and safe clinical use. Mechanisms underlying such differences are incompletely understood, are likely multifactorial, and include genetic and environmental contributions. While accumulating evidence suggests that variants of several genes account for some of the observed response variance, the relative contribution of these factors remains unknown. This study used a twin paradigm to provide a global estimate of the genetic and environmental contributions to inter-individual differences in pain sensitivity and analgesic opioid effects. Eighty one monozygotic and 31 dizygotic twin pairs successfully underwent a computer-controlled infusion with the ?-opioid agonist alfentanil in a single occasion, randomized, double-blind and placebo-controlled study design. Pain sensitivity and analgesic effects were assessed with experimental heat and cold pressor pain models along with important covariates including demographic factors, depression, anxiety, and sleep quality. Significant heritability was detected for cold pressor pain tolerance and opioid-mediated elevations in heat and cold pressor pain thresholds. Genetic effects accounted for 12-60% of the observed response variance. Significant familial effects accounting for 24-32% of observed variance were detected for heat and cold pressor pain thresholds and opioid-mediated elevation in cold pressor pain tolerance. Significant covariates included age, gender, race, education, and anxiety. Results provide a strong rationale for more detailed molecular genetic studies to elucidate mechanisms underlying inter-individual differences in pain sensitivity and analgesic opioid responses. Such studies will require careful consideration of the studied pain phenotype. PMID:22444188

Angst, Martin S; Phillips, Nicholas G; Drover, David R; Tingle, Martha; Ray, Amrita; Swan, Gary E; Lazzeroni, Laura C; Clark, J David

2012-03-22

169

Pain Sensitivity and Opioid Analgesia: A Pharmacogenomic Twin Study  

PubMed Central

Opioids are the cornerstone medication for the management of moderate to severe pain. Unfortunately, vast inter-individual differences in dose requirements complicate their effective and safe clinical use. Mechanisms underlying such differences are incompletely understood, are likely multifactorial, and include genetic and environmental contributions. While accumulating evidence suggests that variants of several genes account for some of the observed response variance, the relative contribution of these factors remains unknown. This study used a twin paradigm to provide a global estimate of the genetic and environmental contributions to inter-individual differences in pain sensitivity and analgesic opioid effects. Eighty one monozygotic and 31 dizygotic twin pairs successfully underwent a computer-controlled infusion with the muopioid agonist alfentanil in a single occasion, randomized, double-blind and placebo-controlled study design. Pain sensitivity and analgesic effects were assessed with experimental heat and cold pressor pain models along with important covariates including demographic factors, depression, anxiety, and sleep quality. Significant heritability was detected for cold pressor pain tolerance and opioid-mediated elevations in heat and cold pressor pain thresholds. Genetic effects accounted for 12–60% of the observed response variance. Significant familial effects accounting for 24–32% of observed variance were detected for heat and cold pressor pain thresholds and opioid-mediated elevation in cold pressor pain tolerance. Significant covariates included age, gender, race, education, and anxiety. Results provide a strong rationale for more detailed molecular genetic studies to elucidate mechanisms underlying inter-individual differences in pain sensitivity and analgesic opioid responses. Such studies will require careful consideration of the studied pain phenotype.

Angst, Martin S.; Phillips, Nicholas G.; Drover, David R.; Tingle, Martha; Ray, Amrita; Swan, Gary E.; Lazzeroni, Laura C.; Clark, J. David

2012-01-01

170

Nonsuicidal self-injury and diminished pain perception: the role of emotion dysregulation.  

PubMed

Nonsuicidal self-injury (NSSI) is the deliberate destruction of one's own body tissue in the absence of suicidal intent (e.g., cutting or burning the skin). Previous studies have found that people with a history of NSSI display diminished pain perception. However, it remains unclear why this effect occurs. In the present study, we used a sample of participants with (n = 25) and without (n = 47) a history of NSSI to test the hypothesis that emotion dysregulation partially explains why NSSI is associated with diminished pain perception. Pain perception was quantified as pain threshold, pain tolerance, and pain intensity ratings assessed during the cold pressor task. Nonsuicidal self-injury was associated with increased emotion dysregulation and diminished pain perception. Results showed that emotion dysregulation was correlated with diminished pain perception within both groups, demonstrating that this association exists regardless of NSSI history. Results also specified that emotion dysregulation partially accounted for the association between NSSI and pain tolerance but not other pain variables. Overall, results were consistent with the hypothesis that emotion dysregulation may increase NSSI risk in part by increasing the willingness to experience the pain involved in self-injury. Studies are needed to more directly investigate this hypothesis. PMID:22208846

Franklin, Joseph C; Aaron, Rachel V; Arthur, Michael S; Shorkey, S Paul; Prinstein, Mitchell J

2011-12-28

171

Comparison of pain models to detect opioid-induced hyperalgesia  

PubMed Central

Objective Chronic opioid therapy may be associated with hyperalgesia. Our objective was to determine if opioid-induced hyperalgesia detection sensitivity is dependent on the stimulus used to detect it. Methods This open design study compared the detection of hyperalgesia in opioid-dependent subjects (n = 16) and healthy control subjects (n = 16) using the following pain stimuli: cold pain, electrical stimulation, mechanical pressure, and ischemic pain. The opioid-dependent subjects were maintained on either methadone (n = 8) or buprenorphine (n = 8) for at least 3 months. None of the controls was dependent on opioids or other drugs of abuse. Results The opioid-dependent subjects were markedly more sensitive than controls to the cold pain test. Compared with the control group, the hazard ratio for ceasing the test due to intolerable pain was 7.7 (95% confidence interval [CI] 2.6–23.3) in the buprenorphine group and 4.5 (95% CI 1.7–15.6) in the methadone group, with similar data for the cold pain threshold. Of the remaining tests, there were differences only for the electrical pain threshold between treatment groups, with the geometric mean threshold in the buprenorphine group being 1.5 (95% CI 1.1–1.9)-fold higher (ie, less sensitive) than that of the controls; the geometric mean for the methadone group was 1.3 (95% CI 1.04–1.7)-fold higher than that of the controls. There were no significant differences between buprenorphine and methadone patients in test responses. Women were more sensitive to the cold pain (hazard ratio for tolerance, 3.1 [95% CI 1.4–7.3]) and ischemic tests (hazard ratio for tolerance, 2.7 [95% CI 1.2–6.1]). There were significant correlations between cold and ischemic tolerances (r = 0.50; P = 0.003) and between electrical and mechanical pain tolerances (r = 0.52; P = 0.002). Conclusion These findings indicate that cold pain is the most suitable of the methods tested to detect opioid-induced hyperalgesia. This is consistent with its sensitivity to detect opioid analgesia.

Krishnan, Sumithra; Salter, Amy; Sullivan, Thomas; Gentgall, Melanie; White, Jason; Rolan, Paul

2012-01-01

172

Pharmacokinetics and tolerability of different doses of fentanyl following sublingual administration of a rapidly dissolving tablet to cancer patients: a new approach to treatment of incident pain  

PubMed Central

Aims It is estimated that two-thirds of cancer patients will at some point during their illness experience breakthrough pain. In this study, the pharmacokinetics of a novel sublingual dosage form of fentanyl developed for breakthrough pain was evaluated. Methods Eleven Caucasian patients (seven male and 4 female, aged 34–75 years, median 60 years) with metastatic malignant disease were recruited initially, but three patients withdrew. Prior to the study all patients were on continuous nonfentanyl opiate medication. The study was a double-blind, cross-over trial, consisting of three 1-day treatment periods. A new rapidly dissolving preparation of fentanyl, was administered sublingually in single doses of 100, 200 and 400 µg, respectively, on three separate occasions. Plasma fentanyl concentrations were determined using liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). Pharmacokinetic parameters were calculated by noncompartment analysis. Tolerability and the occurrence of adverse events were monitored throughout the study by patient questionnaire. Results The data from nine subjects who completed at least two periods were used in the analysis of variance. There were no significant differences between doses (100, 200 and 400 µg) for dose adjusted AUC (F = 0.42, P = 0.6660), dose adjusted Cmax (F = 0.08, P = 0.9206) and Tmax (F = 0.94, P = 0.4107). Thus, these parameters showed dose proportionality. The differences (400–100µg) in dose adjusted AUC from the three-period crossover analysis was ?0.016 min·ng/ml (t = 0.71, P = 0.8718). Interindividual variability in systemic exposure to fentanyl was fairly small (25–40%), which may be related to a good in vivo biopharmaceutical performance of the sublingual tablet, and a relatively small fraction of the dose being swallowed. The first detectable plasma concentration of fentanyl was observed between 8 and 11 min after administration. tmax increased from 39.7 ± 17.4 to 48.7 ± 26.3 and 56.7 ± 24.6 min for the 100, 200 and 400 µg doses, respectively. Adverse events were few and did not increase with increasing dose. Conclusion With this rapidly dissolving fentanyl formulation, the first detectable plasma concentration of fentanyl was observed at 8–11 min after administration. The pharmacokinetics of the drug showed dose proportionately. This formulation of fentanyl seemed to be well tolerated by the patients.

Lennernas, B; Hedner, T; Holmberg, M; Bredenberg, S; Nystrom, C; Lennernas, H

2005-01-01

173

Pain channelopathies  

PubMed Central

Pain remains a major clinical challenge, severely afflicting around 6% of the population at any one time. Channelopathies that underlie monogenic human pain syndromes are of great clinical relevance, as cell surface ion channels are tractable drug targets. The recent discovery that loss-of-function mutations in the sodium channel Nav1.7 underlie a recessive pain-free state in otherwise normal people is particularly significant. Deletion of channel-encoding genes in mice has also provided insights into mammalian pain mechanisms. Ion channels expressed by immune system cells (e.g. P2X7) have been shown to play a pivotal role in changing pain thresholds, whilst channels involved in sensory transduction (e.g. TRPV1), the regulation of neuronal excitability (potassium channels), action potential propagation (sodium channels) and neurotransmitter release (calcium channels) have all been shown to be potentially selective analgesic drug targets in some animal pain models. Migraine and visceral pain have also been associated with voltage-gated ion channel mutations. Insights into such channelopathies thus provide us with a number of potential targets to control pain.

Cregg, Roman; Momin, Aliakmal; Rugiero, Francois; Wood, John N; Zhao, Jing

2010-01-01

174

Sleep and Pain  

Microsoft Academic Search

The high prevalence of sleep disturbance in chronic pain conditions is due in part to bi-directional influences in which pain\\u000a disturbs sleep and poor sleep reduces pain thresholds and aggravates pain. Other variables, especially depression and anxiety,\\u000a may mediate this relationship, although supporting data has been equivocal. Trauma exposure and resulting PTSD symptoms have\\u000a not been adequately evaluated in the

Wilfred R. Pigeon; Hyung Park; Michael J. Sateia

175

Recovery of aversive thresholds following midbrain lesions in the cat  

Microsoft Academic Search

Destruction of ascending pathways in the rostral midbrain of the cat produces striking elevations in aversive or pain thresholds. Similar procedures in humans (mesencephalic tractotomy) lead to a pain relief that is often temporary. To replicate empirically the return of pain found in the neurosurgical clinic, long-term effects of lateral tegmental (LT) lesions in 8 cats were analyzed. Aversive thresholds

Wallace J. Orlowsky; Murray Glusman

1969-01-01

176

The relationship between neck pain and physical activity.  

PubMed

Neck pain is a significant societal burden due to its high prevalence and healthcare costs. While physical activity can help to manage other forms of chronic musculoskeletal pain, little data exists on the relationship between physical activity and neck pain. The purpose of this study was to compare physical activity levels between individuals with neck pain and healthy controls, and then to relate disability, fear of movement, and pain sensitivity measures to physical activity levels in each of the two participant groups. 21 participants were recruited for each of the two participant groups (n = 42). Data collection included the use of the Neck Disability Index, the Tampa Scale for Kinesiophobia, electrocutaneous (Neurometer® CPT) and pressure stimulation (JTech algometer) for quantitative sensory testing, and 5 days of subjective (Rapid Assessment of Physical Activity) and objective (BioTrainer II) measurements of physical activity. Analysis of Variance and Pearson's Correlation were used to determine if differences and relationships exist between dependent variables both within and between groups. The results show that individuals with mild neck pain and healthy controls do not differ in subjectively and objectively measured physical activity. While participants with neck pain reported higher neck disability and fear of movement, these factors did not significantly relate to physical activity levels. Perceived activity level was related to pain threshold and tolerance at local neck muscles sites (C2 paraspinal muscle and upper trapezius muscle), whereas measured activity was related to generalized pain sensitivity, as measured at the tibialis anterior muscle site. PMID:24133553

Cheung, Janice; Kajaks, Tara; Macdermid, Joy C

2013-09-20

177

The Relationship Between Neck Pain and Physical Activity  

PubMed Central

Neck pain is a significant societal burden due to its high prevalence and healthcare costs. While physical activity can help to manage other forms of chronic musculoskeletal pain, little data exists on the relationship between physical activity and neck pain. The purpose of this study was to compare physical activity levels between individuals with neck pain and healthy controls, and then to relate disability, fear of movement, and pain sensitivity measures to physical activity levels in each of the two participant groups. 21 participants were recruited for each of the two participant groups (n = 42). Data collection included the use of the Neck Disability Index, the Tampa Scale for Kinesiophobia, electrocutaneous (Neurometer® CPT) and pressure stimulation (JTech algometer) for quantitative sensory testing, and 5 days of subjective (Rapid Assessment of Physical Activity) and objective (BioTrainer II) measurements of physical activity. Analysis of Variance and Pearson’s Correlation were used to determine if differences and relationships exist between dependent variables both within and between groups. The results show that individuals with mild neck pain and healthy controls do not differ in subjectively and objectively measured physical activity. While participants with neck pain reported higher neck disability and fear of movement, these factors did not significantly relate to physical activity levels. Perceived activity level was related to pain threshold and tolerance at local neck muscles sites (C2 paraspinal muscle and upper trapezius muscle), whereas measured activity was related to generalized pain sensitivity, as measured at the tibialis anterior muscle site.

Cheung, Janice; Kajaks, Tara; MacDermid, Joy C.

2013-01-01

178

Modulation of learning, pain thresholds, and thermoregulation in the rat by preparations of free purified alpha-linolenic and linoleic acids: determination of the optimal omega 3-to-omega 6 ratio.  

PubMed Central

Ingested polyunsaturated fatty acids are postulated to lead to changes in central nervous system activity, presumably by altering the lipid composition of neuronal membranes. In support of this hypothesis, we and other investigators have previously demonstrated cognitive effects in rats fed oils that contain both alpha-linolenic acid (18:3 omega 3) and linoleic acid (18:2 omega 6), with the relative content of alpha-linolenic acid being seen as the critical variable. The present study in rats examined the effects of preparations containing different ratios of highly purified free alpha-linolenic acid to linoleic acid (about 25 mg/kg of body weight daily) on learning performance (Morris water tank), pain thresholds (heated plate), and thermoregulatory control of d-amphetamine-induced hypothermia during 4 weeks of treatment. Preparations with omega 3-to-omega 6 ratios ranging from 1:3.5 to 1:5 (specifically a ratio of 1:4) produced significant favorable effects on all of these variables. Although the specific mode of action remains to be elucidated, these results suggest that such preparations of free fatty acids should be evaluated in the treatment of memory disorders and pain conditions.

Yehuda, S; Carasso, R L

1993-01-01

179

Fentanyl buccal tablet for the relief of breakthrough pain in opioid-tolerant adult patients with chronic neuropathic pain: a multicenter, randomized, double-blind, placebo-controlled study  

Microsoft Academic Search

Background:Patients with chronic noncancer pain, including neuropathic pain, may have transitory exacerbations of pain (median duration, 60 minutes), termed breakthrough pain (BTP), that may reach peak intensity within minutes. Typical short-acting oral opioids may not provide sufficiently rapid relief (30- to 60-minute onset of analgesia). The fentanyl buccal tablet (FBT) provides a rapid onset of analgesia (10–15 minutes) by enhancing

David M. Simpson; John Messina; Fang Xie; Martin Hale

2007-01-01

180

Efficacy and tolerability of intranasal fentanyl spray 50 to 200 ?g for breakthrough pain in patients with cancer: A phase III, multinational, randomized, double-blind, placebo-controlled, crossover trial with a 10-month, open-label extension treatment period  

Microsoft Academic Search

Objective: This trial investigated the efficacy and long-term tolerability of intranasal fentanyl spray (INFS) 50 to 200 ?g in the treatment of breakthrough pain in opioid-tolerant patients with cancer.Methods: This Phase III, double-blind, randomized, placebo-controlled, crossover trial was conducted at pain centers, anesthesiology departments, palliative care units, and oncology clinics in Austria, Denmark, France, Germany, and Poland. Eligible patients were

Hans Georg Kress; Anna Oro?ska; Zbigniew Kaczmarek; Stein Kaasa; Torben Colberg; Thomas Nolte

2009-01-01

181

Relationship between dry eye symptoms and pain sensitivity.  

PubMed

IMPORTANCE Dry eye disease (DED) is common, but little is known about factors contributing to symptoms of dry eye, given the poor correlation between these symptoms and objective signs at the ocular surface. OBJECTIVE To explore whether pain sensitivity plays a role in patients' experience of DED symptoms. DESIGN, SETTING, AND PARTICIPANTS A population-based cross-sectional study of 1635 female twin volunteers, aged 20 to 83 years, from the TwinsUK adult registry. MAIN OUTCOMES AND MEASURES Dry eye disease was diagnosed if participants had at least 1 of the following: (1) a diagnosis of DED by a clinician, (2) the prescription of artificial tears, and/or (3) symptoms of dry eyes for at least 3 months. A subset of 689 women completed the Ocular Surface Disease Index (OSDI) questionnaire. Quantitative sensory testing using heat stimulus on the forearm was used to assess pain sensitivity (heat pain threshold [HPT]) and pain tolerance (heat pain suprathreshold [HPST]). RESULTS Of the 1622 participants included, 438 (27.0%) were categorized as having DED. Women with DED showed a significantly lower HPT (P?=?.03) and HPST (P?=?.003)-and hence had higher pain sensitivity-than those without DED. A strong significant association between the presence of pain symptoms on the OSDI and the HPT and HPST was found (P?=?.008 for the HPT and P?=?.003 for the HPST). In addition, participants with an HPT below the median had DED pain symptoms almost twice as often as those with an HPT above the median (31.2% vs 20.5%; odds ratio, 1.76; 95% CI, 1.15-2.71; P = .01). CONCLUSIONS AND RELEVANCE High pain sensitivity and low pain tolerance are associated with symptoms of DED, adding to previous associations of the severity of tear insufficiency, cell damage, and psychological factors. Management of DED symptoms is complex, and physicians need to consider the holistic picture, rather than simply treating ocular signs. PMID:23907167

Vehof, Jelle; Kozareva, Diana; Hysi, Pirro G; Harris, Juliette; Nessa, Ayrun; Williams, Frances K; Bennett, David L H; McMahon, Steve B; Fahy, Samantha J; Direk, Kenan; Spector, Tim D; Hammond, Christopher J

2013-10-01

182

[Effect of spinal glutamate transporter 1 on chronic constriction injury of sciatic nerve and morphine tolerance of rats].  

PubMed

In order to investigate the role of spinal glutamate transporter 1 (GLT-1) in the neuropathic pain and morphine tolerance, rat chronic constriction injury (CCI) of sciatic nerve was performed, and the mechanical allodynia was evaluated by mechanical withdrawal threshold (MWT), the expression of GLT-1 was measured by real-time PCR and Western blotting analysis. The results showed that compared to sham group, the MWT of CCI group had decreased approximately 80%. Administration of morphine alone could develop tolerance rapidly in initial two days, and then had no significant difference with CCI group, the expression of GLT-1 was down-regulated. Ceftriaxone sodium alone could improve mechanical allodynia. Co-administration of ceftriaxone sodium with morphine attenuated morphine tolerance and up-regulated GLT-1 expression, and the MWT remained at high level after 6 days. In conclusion, change of spinal GLT-1 expression and function has close correlation with the development of neuropathic pain and morphine tolerance. PMID:19806886

Yan, Hui; Li, Cheng-Min; Li, Yu-Lei; Gong, Ze-Hui

2009-06-01

183

Cholecystokinin receptors mediate tolerance to the analgesic effect of TENS in arthritic rats.  

PubMed

Transcutaneous electrical nerve stimulation (TENS) is a treatment for pain that involves placement of electrical stimulation through the skin for pain relief. Previous work from our laboratory shows that repeated application of TENS produces analgesic tolerance by the fourth day and a concomitant cross-tolerance at spinal opioid receptors. Prior pharmacological studies show that blockade of cholecystokinin (CCK) receptors systemically and spinally prevents the development of analgesic tolerance to repeated doses of opioid agonists. We therefore hypothesized that systemic and intrathecal blockade of CCK receptors would prevent the development of analgesic tolerance to TENS, and cross-tolerance at spinal opioid receptors. In animals with knee joint inflammation (3% kaolin/carrageenan), high (100Hz) or low frequency (4Hz) TENS was applied daily and the mechanical withdrawal thresholds of the muscle and paw were examined. We tested thresholds before and after inflammation, and before and after TENS. Animals treated systemically, prior to TENS, with the CCK antagonist, proglumide, did not develop tolerance to repeated application of TENS on the fourth day. Spinal blockade of CCK-A or CCK-B receptors blocked the development of tolerance to high and low frequency TENS, respectively. In the same animals we show that spinal blockade of CCK-A receptors prevents cross-tolerance at spinal delta-opioid receptors that normally occurs with high frequency TENS; and blockade of CCK-B receptors prevents cross-tolerance at spinal mu-opioid receptors that normally occurs with low frequency TENS. Thus, we conclude that blockade of CCK receptors prevents the development of analgesic tolerance to repeated application of TENS in a frequency-dependent manner. PMID:19944533

DeSantana, Josimari M; da Silva, Luis Felipe S; Sluka, Kathleen A

2009-11-26

184

Buspirone attenuates tolerance to analgesic effect of morphine in mice with skin cancer.  

PubMed

Adjuvant drugs that can delay tolerance to morphine analgesia may lead to improved management of pain in chronic disease such as cancer. This study was aimed to investigate effect of buspirone, as a partial agonist of 5-HT1A receptor, on tolerance induced to morphine analgesic effect in animals with skin cancer. Study was carried on female Swiss albino mice. For skin tumorigensis, mice were treated with single dose of 7,12-dimethylbenz(a)anthracene (DMBA) and promoted by multiple dose of croton oil. Tolerance to morphine analgesia was induced by daily subcutaneous (sc) injection of morphine (5mg/kg for 30 days) and assayed by using the hot plate method. Results obtained from this study showed that pain threshold in mice with skin cancer were significantly lower. Tolerance to analgesic effect of morphine (5 mg/kg, sc) was appeared at day 15, whereas, in normal and skin tumor bearing mice co-treated daily with morphine (5 mg/kg, sc) and three different intraperitoneal (ip) doses of buspirone (5, 7.5 and 10 mg/kg) tolerance was observed at days 25 and 30. In conclusion our data indicate that concurrent use of morphine with buspirone may produce good cancer pain control and attenuate development of tolerance. PMID:20363700

Nayebi, Alireza Mohajjel; Rezazadeh, Hassan; Nourafkan, Mostafa

2010-04-01

185

The impact of emotion-related autonomic nervous system responsiveness on pain sensitivity in female patients with fibromyalgia.  

PubMed

Objective Patients with fibromyalgia have shown hyporeactive autonomic nervous system (ANS) responses to physical stressors, augmented pain to ANS changes, and heightened negative emotions, which can increase pain. This study examined ANS reactivity to negative emotions and its association with pain in fibromyalgia and control participants. Methods Sixty-two women with fibromyalgia and 59 women in a control group recalled neutral, and anger- and sadness-eliciting experiences while ANS activity was monitored. Clinical and experimental pain were assessed in response to each emotion. Results Compared with neutral recall, heart rate (p = .050), mean arterial pressure (p < .001), and high-frequency heart rate variability (p = .012) increased in response to sadness, whereas heart rate decreased (p = .002) and mean arterial pressure increased (p < .001) in response to anger; however, ANS responses did not differ between patients and control participants (all p > .29). Among patients only, decreased preejection period (anger-pain threshold: r = 0.31, p = .018) and total peripheral resistance in response to negative emotions (anger-pain tolerance: r = 0.35, p = .025; sadness-pain threshold: r = 0.51, p < .001; sadness-pain tolerance: r = 0.61, p < .001) correlated with more pain. Conclusions These data suggest that the ANS is not hyporesponsive to elicited emotions in fibromyalgia; however, patients with a larger pain response showed an ANS response pattern reflecting heightened ?-adrenergic and reduced ?-adrenergic reactivity. Future research should test whether a specific ANS response pattern to emotions is a consequence of increased pain or whether it amplifies pain. PMID:23922401

van Middendorp, Henriët; Lumley, Mark A; Houtveen, Jan H; Jacobs, Johannes W G; Bijlsma, Johannes W J; Geenen, Rinie

2013-08-06

186

Efficacy and tolerance of repeated oral doses of tolperisone hydrochloride in the treatment of painful reflex muscle spasm: results of a prospective placebo-controlled double-blind trial.  

PubMed

The efficacy and safety of oral tolperisone hydrochloride (Mydocalm) in the treatment of painful reflex muscle spasm was assessed in a prospective, randomized, double-blind, placebo-controlled trial. A total of 138 patients, aged between 20 and 75 years, with painful reflex muscle spasm associated with diseases of the spinal column or proximal joints were enrolled in eight rehabilitation centers. Patients were randomized to receive either 300 mg tolperisone hydrochloride or placebo for a period of 21 days. Both treatment groups recovered during the 3 weeks rehabilitation program. However, tolperisone hydrochloride proved to be significantly superior to placebo: the change score of the pressure pain threshold as the primary target parameter significantly increased during therapy with tolperisone hydrochloride (P = 0.03, valid-case-analysis) compared to the results obtained on placebo treatment. The overall assessment of efficacy by the patient also demonstrated significant differences in favor of tolperisone hydrochloride. Best results were seen in patients aged between 40 and 60 years with a history of complaints shorter than 1 year and with concomitant physical therapy. The evaluation of safety data, i.e., adverse events, biochemical and hematological laboratory parameters, demonstrated no differences between tolperisone hydrochloride and placebo. As a conclusion tolperisone hydrochloride represents an effective and safe treatment of painful reflex muscle spasm without the typical side effects of centrally active muscle relaxants. PMID:8951937

Pratzel, H G; Alken, R G; Ramm, S

1996-10-01

187

Entrapment of adult fingers between window glass and seal entry of a motor vehicle side door: an experimental study for investigation of the force at the subjective pain threshold.  

PubMed

In modern motor vehicles with automatic power windows, a potential hazard exists for jam events of fingers between the window glass and seal entry. This study determined entrapment forces acting on adult fingers at the subjective maximum pain threshold during entrapment in such windows. The length and the girth of the proximal and distal interphalangeal joints of the triphalangeal fingers of the right hands of 109 participants (60 men, 49 women) were measured; the diameter was calculated from girth, which was assumed to be circular. The automatic power window system of a motor vehicle side door was changed to a mechanical system. During entrapment the force distributed across the four proximal interphalangeal joints (PIPs), and separately on the proximal interphalangeal (iPIP) and then the distal interphalangeal (iDIP) joints of the index finger was measured using a customized force sensor. The maximum bearable entrapment force was 97.2 ± 51.8 N for the PIPs, 43.4 ± 19.9 N for the iPIP, and 36.9 ± 17.8 N for the iDIP. The positive correlation between finger diameter and maximum entrapment force was significant. Particularly with regard to the risk to children's fingers, the 100 N statutory boundary value for closing force of electronic power windows should be reduced. PMID:21601859

Hohendorff, B; Weidermann, C; Pollinger, P; Burkhart, K J; Konerding, M A; Prommersberger, K J; Rommens, P M

2011-05-23

188

Differential cross-tolerance development between single and repeated immobilization stress on the antinociceptive effect induced by ?-endorphin, 5-hydroxytryptamine, morphine, and WIN55,212-2 in the inflammatory mouse pain mode.  

PubMed

We have evaluated the possible underlying mechanisms of immobilization stress-induced analgesia (SIA) by behavioral cross-tolerance studies and molecular studies. In the behavioral studies, the cross-tolerance between single or repeated immobilization SIA and the antinociceptive effects of ?-endorphin, morphine, 5-hydroxytryptamine (5-HT), or WIN55,212-2 were assessed. Both single and repeated (×7) immobilization stress significantly attenuated the ?-endorphin and 5-hydroxytryptamine-induced antinociception in the 2nd phase of formalin response, respectively. However, these cross-tolerances disappeared in prolonged repetition of the stress (×14). Neither single nor repeated (×7 and ×14) immobilization stress affected the antinociceptive effect of morphine or WIN55,212-2 at all. We also found that immobilization stress activated hypothalamic proopiomelanocortin (POMC) gene and ?-endorphin expression. Since, it has potent inhibitory activity on the noxious stimuli-induced POMC expression, immobilization stress seemed to dissipate the POMC gene expression process. Meanwhile, we did not find any changes in the opioid receptors' (mu-, delta- and kappa-receptor) and the cannabinoid receptors' (CB1 and CB2) expressions in the midbrain regions elicited by single or repeated stress. These results suggested that a single immobilization stress activates the descending pain modulatory system, which is mainly mediated through endorphinergic and serotonergic activation. Moreover, the tolerance of SIA induced by repeated stresses may be due to the prolonged activation of these systems induced by repeated immobilization. PMID:21380811

Seo, Young-Jun; Kwon, Min-Soo; Choi, Seung-Min; Lee, Jin-Koo; Park, Soo-Hyun; Jung, Jun-Sub; Sim, Yun-Beom; Suh, Hong-Won

2011-03-06

189

Effects of L-5HTP with and without carbidopa on plasma beta-endorphin and pain perception. Possible implications in migraine prophylaxis.  

PubMed

L-Tryptophan (L-TP) has been used in migraine and other pain conditions. The mechanism underlying the analgesic effect is still partly undefined. In this study the effects of subchronic administration of L-5-hydroxy-tryptophan (L-5HTP) (with and without carbidopa) on plasma beta-endorphin (beta-EP) levels and subjective pain threshold and tolerance were investigated in seven healthy volunteers. To measure also an objective indicator for pain, the nociceptive flexion reflex threshold was studied. L-5HTP treatment with and without carbidopa administration increased beta-EP levels significantly (p less than 0.05). L-5HTP plus carbidopa induced an increase in beta-EP significantly (p less than 0.05) higher than that after L-5HTP alone. Neither subjective pain threshold and tolerance nor RIII threshold was modified by either treatment. Our data seem to point to the existence of a complex linkage between plasma opioid levels and pain perception. PMID:2948652

Genazzani, A R; Sandrini, G; Facchinetti, F; Rizzo, V; Alfonsi, E; Sances, G; Calvani, M; Nappi, G

1986-12-01

190

Effects of L-5HTP with and without carbidopa on plasma beta-endorphin and pain perception: possible implications in migraine prophylaxis.  

PubMed

L-Tryptophan (L-TP) has been used in migraine and other pain conditions. The mechanism underlying the analgesic effect is still partly undefined. In this study the effects of subchronic administration of L-5-hydroxytryptophan (L-5HTP) (with and without carbidopa) on plasma beta-endorphin (beta-EP) levels and subjective pain threshold and tolerance were investigated in seven healthy volunteers. To measure also an objective indicator of pain, the nociceptive flexion reflex threshold was studied. L-5HTP treatment with and without carbidopa administration increased beta-EP levels significantly (p less than 0.05). L-5HTP plus carbidopa induced an increase in beta-EP significantly (p less than 0.05) greater than that induced by L-5HTP alone. Neither the subjective pain threshold and tolerance nor the RIII threshold was modified by either treatment. Our data seem to point to the existence of a complex linkage between plasma opioid levels and pain perception. PMID:2945645

Genazzani, A R; Sandrini, G; Facchinetti, F; Rizzo, V; Alfonsi, E; Sances, G; Calvani, M; Nappi, G

1986-09-01

191

Neurophysiological characterization of postherniotomy pain.  

PubMed

Inguinal herniotomy is one of the most frequent surgical procedures and chronic pain affecting everyday activities is reported in approximately 10% of patients. However, the neurophysiological changes and underlying pathophysiological mechanisms of postherniotomy pain are not known in detail, thereby precluding advances in treatment strategies and prophylaxis. Therefore, we examined forty-six patients reporting moderate to severe postherniotomy pain affecting daily activities for more than a year postoperatively, and compared them with a control group of patients without pain 1 yr postoperatively. A quantitative sensory testing protocol was used, assessing sensory dysfunction type, location and severity. We assessed the protocol test-retest variability using data from healthy control subjects. All patients (pain and pain-free) had signs of nerve damage, seen as sensory dysfunction. Detection thresholds for tactile and warmth stimulation were significantly increased while cold detection and pressure pain detection thresholds were significantly decreased in pain patients compared to controls. Repetitive punctuate and brush stimulation resulted in significantly more frequent and intense pain on the painful side than on the unaffected side in pain patients, and was not observed in controls. Our findings showed large and small fiber dysfunction in both pain and pain-free patients but more profound in pain patients and with signs of central sensitization (abnormal temporal summation). The specific finding of reduced pain detection threshold over the external inguinal annulus is consistent with damage to the cutaneous innervation territory of nervous structures in the inguinal region. The correspondence between pain location and sensory disturbance suggests that the pain is neuropathic in nature. Whether the underlying pathophysiological mechanisms are related to direct intraoperative nerve injury or nerve injury due to an inflammatory mesh response remains to be determined. PMID:17976914

Aasvang, Eske Kvanner; Brandsborg, Birgitte; Christensen, Bente; Jensen, Troels Staehelin; Kehlet, Henrik

2007-10-31

192

Efficacy and tolerability of the cyclooxygenase-2 inhibitor L-791,515 compared with ibuprofen in patients with postoperative dental pain  

Microsoft Academic Search

Background: L-791,515 (L)[(5S)-5-ethyl-3-isopropoxy-5-methyl-4-[4-(methylsulfonyl)phenyl]furan-2(5 H)-one] is a selective cyclooxygenase-2 inhibitor investigated for treatment of acute pain and inflammation.Methods: This single-dose, randomized, double-blind, double-dummy, placebo-controlled, parallel-group study compared L 12.5, 50, and 100 mg with ibuprofen 400 mg or placebo in patients who experienced moderate-to-severe pain after surgical removal of? 2 third molars. Overall analgesic effect, duration of effect, time to onset

J. I. Schwartz; J. R. Fricke; P. N. Kotey; D. L. Ebel; J. A. Wagner; K. M. Gottesdiener

2005-01-01

193

Preliminary assessment of the efficacy, tolerability and safety of a cannabis-based medicine (Sativex) in the treatment of pain caused by rheumatoid arthritis  

Microsoft Academic Search

Objectives. To assess the efficacy of a cannabis-based medicine (CBM) in the treatment of pain due to rheumatoid arthritis (RA). Methods. We compared a CBM (Sativex) with placebo in a randomized, double-blind, parallel group study in 58 patients over 5 weeks of treatment. The CBM was administered by oromucosal spray in the evening and assessments were made the following morning.

D. R. Blake; P. Robson; M. Ho; R. W. Jubb; C. S. McCabe

2005-01-01

194

Effects of transcranial direct current stimulation on pain perception and working memory.  

PubMed

Previous studies have shown that non-invasive stimulation of the dorsolateral prefrontal cortex (DLPFC) could modulate experimentally induced pain and working memory (WM) in healthy subjects. However, the two aspects have never been assessed concomitantly. The present study was set up to investigate the effects of transcranial direct current stimulation (tDCS) of the DLPFC on thermal pain and WM in the same population of healthy volunteers. In a randomized and balanced order of different sessions separated by 1 week, 20 min of 2 mA anodal, cathodal or sham tDCS were applied to the left or right DLPFC in two separate experiments. Twelve healthy volunteers were enrolled for each stimulated hemisphere. Warm and cold detection thresholds, heat and cold pain thresholds as well as heat pain tolerance thresholds were measured before, during and following tDCS. WM was assessed by a 2-back task applied once during cortical stimulation. Anodal tDCS of the right DLPFC led to an increase of tolerance to heat pain. The 2-back task revealed fewer outliers during cathodal tDCS of the left DLPFC. The present data show an involvement of the DLPFC in the processing of pain and WM. There was no correlation between these findings, suggesting that the analgesic effects of cortical stimulation are not associated with cognitive processing. However, this conclusion is difficult to affirm because of some limitations of the study regarding the parameters of stimulation or a ceiling effect of the 2-back task for instance. PMID:22337597

Mylius, V; Jung, M; Menzler, K; Haag, A; Khader, P H; Oertel, W H; Rosenow, F; Lefaucheur, J-P

2012-01-19

195

A systematic literature review of 10 years of research on sex/gender and experimental pain perception - part 1: are there really differences between women and men?  

PubMed

The purpose of this systematic review was to summarize and critically appraise the results of 10 years of human laboratory research on pain and sex/gender. An electronic search strategy was designed by a medical librarian and conducted in multiple databases. A total of 172 articles published between 1998 and 2008 were retrieved, analyzed, and synthesized. The first set of results (122 articles), which is presented in this paper, examined sex difference in the perception of laboratory-induced thermal, pressure, ischemic, muscle, electrical, chemical, and visceral pain in healthy subjects. This review suggests that females (F) and males (M) have comparable thresholds for cold and ischemic pain, while pressure pain thresholds are lower in F than M. There is strong evidence that F tolerate less thermal (heat, cold) and pressure pain than M but it is not the case for tolerance to ischemic pain, which is comparable in both sexes. The majority of the studies that measured pain intensity and unpleasantness showed no sex difference in many pain modalities. In summary, 10 years of laboratory research have not been successful in producing a clear and consistent pattern of sex differences in human pain sensitivity, even with the use of deep, tonic, long-lasting stimuli, which are known to better mimic clinical pain. Whether laboratory studies in healthy subjects are the best paradigm to investigate sex differences in pain perception is open to question and should be discussed with a view to enhancing the clinical relevance of these experiments and developing new research avenues. PMID:22192712

Racine, Mélanie; Tousignant-Laflamme, Yannick; Kloda, Lorie A; Dion, Dominique; Dupuis, Gilles; Choinière, Manon

2011-12-20

196

Experimental pain responses in children with chronic pain and in healthy children: How do they differ?  

PubMed Central

BACKGROUND: Extant research comparing laboratory pain responses of children with chronic pain with healthy controls is mixed, with some studies indicating lower pain responsivity for controls and others showing no differences. Few studies have included different pain modalities or assessment protocols. OBJECTIVES: To compare pain responses among 26 children (18 girls) with chronic pain and matched controls (mean age 14.8 years), to laboratory tasks involving thermal heat, pressure and cold pain. Responses to cold pain were assessed using two different protocols: an initial trial of unspecified duration and a second trial of specified duration. METHODS: Four trials of pressure pain and of thermal heat pain stimuli, all of unspecified duration, were administered, as well as the two cold pain trials. Heart rate and blood pressure were assessed at baseline and after completion of the pain tasks. RESULTS: Pain tolerance and pain intensity did not differ between children with chronic pain and controls for the unspecified trials. For the specified cold pressor trial, 92% of children with chronic pain completed the entire trial compared with only 61.5% of controls. Children with chronic pain exhibited a trend toward higher baseline and postsession heart rate and reported more anxiety and depression symptoms compared with control children. CONCLUSIONS: Contextual factors related to the fixed trial may have exerted a greater influence on pain tolerance in children with chronic pain relative to controls. Children with chronic pain demonstrated a tendency toward increased arousal in anticipation of and following pain induction compared with controls.

Tsao, Jennie CI; Evans, Subhadra; Seidman, Laura C; Zeltzer, Lonnie K

2012-01-01

197

Threshold Logic Drempellogica.  

National Technical Information Service (NTIS)

The theory is discussed of presently available threshold logic circuits, and an analysis of threshold functions is presented. An operational threshold gate adding circuit in TTL technology is described, and the difficulty of improving logic in complex cir...

C. Vader J. W. M. Wasser

1973-01-01

198

MOS Threshold Logic II.  

National Technical Information Service (NTIS)

The program represents the second phase in the Development of MOS threshold logic. Studies were made previously, indicating the limitations and applications of MOS threshold gates. Now, threshold gates were integrated for use in parallel array multipliers...

D. Hampel K. J. Prost N. Scheinberg

1973-01-01

199

The role of beta-arrestin2 in the severity of antinociceptive tolerance and physical dependence induced by different opioid pain therapeutics  

PubMed Central

Ligands acting at the same receptor can differentially activate distinct signal transduction pathways, which in turn, can have diverse functional consequences. Further, receptors expressed in different tissues may utilize intracellular signaling proteins in response to a ligand differently as well. The mu opioid receptor (MOR), which mediates many of the pharmacological actions of opiate therapeutics, is also subject to differential signaling in response to diverse agonists. To study the effect of diverse agonists on MOR signaling, we examined the effects of chronic opiate treatment on two distinct physiological endpoints, antinociceptive tolerance and physical dependence, in mice lacking the intracellular regulatory molecule, ?arrestin2. While ?arrestin2 knockout (?arr2-KO) mice do not become tolerant to the antinociceptive effects of chronic morphine in a hot plate test, tolerance develops to the same degree in both wild type and ?arr2-KO mice following chronic infusion with methadone, fentanyl, and oxycodone. Studies here also assess the severity of withdrawal signs precipitated by naloxone following chronic infusions at three different doses of each opiate agonist. While there are no differences in withdrawal responses between genotypes at the highest dose of morphine tested (48 mg/kg/day), the ?arr2-KO mice display several less severe withdrawal responses when the infusion dose is lowered (12 or 24 mg/kg/day). Chronic infusion of methadone, fentanyl, and oxycodone all lead to equivalent naloxone-precipitated withdrawal responses in both genotypes at all doses tested. These results lend further evidence that distinct agonists can differentially impact on opioid-mediated responses in vivo in a ?arrestin2-dependent manner.

Raehal, Kirsten M.; Bohn, Laura M.

2010-01-01

200

The role of beta-arrestin2 in the severity of antinociceptive tolerance and physical dependence induced by different opioid pain therapeutics.  

PubMed

Ligands acting at the same receptor can differentially activate distinct signal transduction pathways, which in turn, can have diverse functional consequences. Further, receptors expressed in different tissues may utilize intracellular signaling proteins in response to a ligand differently as well. The mu opioid receptor (MOR), which mediates many of the pharmacological actions of opiate therapeutics, is also subject to differential signaling in response to diverse agonists. To study the effect of diverse agonists on MOR signaling, we examined the effects of chronic opiate treatment on two distinct physiological endpoints, antinociceptive tolerance and physical dependence, in mice lacking the intracellular regulatory molecule, ?arrestin2. While ?arrestin2 knockout (?arr2-KO) mice do not become tolerant to the antinociceptive effects of chronic morphine in a hot plate test, tolerance develops to the same degree in both wild type and ?arr2-KO mice following chronic infusion with methadone, fentanyl, and oxycodone. Studies here also assess the severity of withdrawal signs precipitated by naloxone following chronic infusions at three different doses of each opiate agonist. While there are no differences in withdrawal responses between genotypes at the highest dose of morphine tested (48 mg/kg/day), the ?arr2-KO mice display several less severe withdrawal responses when the infusion dose is lowered (12 or 24 mg/kg/day). Chronic infusion of methadone, fentanyl, and oxycodone all lead to equivalent naloxone-precipitated withdrawal responses in both genotypes at all doses tested. These results lend further evidence that distinct agonists can differentially impact on opioid-mediated responses in vivo in a ?arrestin2-dependent manner. PMID:20713067

Raehal, Kirsten M; Bohn, Laura M

2010-08-14

201

Hypersensitivity in muscle pain syndromes  

Microsoft Academic Search

The aim of this review is to present research that has a bearing on the pathogenesis of hypersensitivity in muscle pain syndromes.\\u000a Allodynia and hyperalgesia in these syndromes can be segmental or generalized and temporary or permanent. Hypersensitivity\\u000a in muscle pain conditions in the clinic is best diagnosed by determining the pressure pain threshold. In a disorder such as\\u000a fibromyalgia,

Karl G. Henriksson

2003-01-01

202

The effect of paracetamol and tropisetron on pain: experimental studies and a review of published data.  

PubMed

Experimental studies suggest that paracetamol-induced analgesia is mediated via central serotonergic pathways and attenuated by 5-HT3-antagonists. However, clinical studies do not support this, and 5-HT3-antagonists are expected to reduce pain by blocking the descending pronociceptive pathway. The current project tested whether tropisetron attenuates analgesia by paracetamol. Two randomized, double-blind, crossover studies with 18 healthy male volunteers in each were performed. Pain stimuli were cold water immersion (cold pressor test), contact heat pain (study 1) and electrical stimulation (study 2). In both studies, tropisetron 5 mg i.v. or saline was administered, followed by paracetamol 2 g i.v. 30 min. later. Individual changes in heat and cold pain intensity, cold pain tolerance and unpleasantness were recorded. The same thresholds were also expressed as scores (% of the individual score at baseline). Additionally, previously published findings on the effects of paracetamol and its interaction with 5HT3-antagonists in human experimental pain models were reviewed. After calculation of the sensory and pain scores (%), tropisetron seemed to amplify the analgesic action of paracetamol. Paracetamol 2 g i.v. did not show any statistically significant analgesia in thermal tests (study 1), or differences in sensory, pain detection or moderate pain thresholds of the electrical stimulus (study 2). As paracetamol did not have a measurable analgesic effect in these tests, no conclusions can be drawn about the interaction between paracetamol and tropisetron. However, tropisetron may have an analgesic effect of its own. Clinicians should not avoid using these drugs together, unless larger clinical studies indicate otherwise. PMID:22905891

Tiippana, Elina; Hamunen, Katri; Kontinen, Vesa; Kalso, Eija

2012-10-20

203

Postamputation pain: studies on mechanisms.  

PubMed

Amputation is followed by both painful and non-painful phantom phenomena in a large number of amputees. Non-painful phantom sensations rarely pose any clinical problem, but 60-80% of all amputees also experience painful sensations (i.e. phantom pain) located to the missing limb. The severity of phantom pain usually decreases with time, but severe pain persists in 5-10% of patients. Pain in the residual limb (i.e. stump pain) is another consequence of amputation. Both stump and phantom pain can be very difficult to treat. Treatment guidelines used for other neuropathic pain conditions are probably the best approximation, especially for the treatment of stump pain. The aim of the present doctoral thesis was to explore some of the mechanisms underlying pain after amputation. Ten studies were carried out (I-X). My PhD thesis from 1998 dealt with pain before the amputation and showed that preamputation pain increases the risk of phantom pain after amputation (I). A perioperative epidural blockade, however, did not reduce the incidence of pain or abnormal sensory phenomena after amputation (II, III). The importance of sensitization before amputation for the subsequent development of pain is supported by study IV, in which pressure pain thresholds obtained at the limb before amputation were inversely related to stump and phantom pain after 1 week. Afferent input from the periphery is likely to contribute to postamputation pain as sodium channels were upregulated in human neuromas (VI), although neuroma removal did not always alleviate phantom pain (V). Sensitization of neurons in the spinal cord also seems to be involved in pain after amputation as phantom pain was reduced by ketamine, an NMDA-receptor antagonist. Another NMDA-receptor antagonist, memantine, and gabapentin, a drug working by binding to the ?2?-subunit of voltage-gated calcium channels, had no effect on phantom pain (VII-IX). Supraspinal factors are also important for pain after amputation as catastrophizing was associated with phantom pain (X). In conclusion, the present doctoral thesis confirmed and expanded the findings by others that several mechanisms are involved in the development and maintenance of phantom pain. A better understanding of the underlying mechanisms will hopefully lead to improved treatment of pain after amputation in the future. PMID:23158899

Nikolajsen, Lone

2012-10-01

204

Pain sensitivity, cerebral laterality, and negative affect  

Microsoft Academic Search

The right hemisphere is assumed to play a unique role for pain sensitivity and negative affect. Pressure pain thresholds were assessed daily in eight right-handed participants over a 6-week period in order to obtain reliable measures of pain sensitivity unaffected by situational influences. In an additional session, cerebral laterality was assessed with behavioral and an EEG measures. Psychometric measures were

Paul Pauli; Georg Wiedemann; Matthias Nickola

1999-01-01

205

Chronic pain: a neuroscientific understanding.  

PubMed

The neuroscientific understanding of chronic pain presented evolved through the integration of clinical, research and theoretical conceptualizations associated with chronic idiopathic orofacial pain after posing the following three questions: (1) What if chronic idiopathic orofacial pain was viewed from a neuroscientific perspective as part of a global syndrome rather than a site-specific anatomo-physiological perspective? (2) What if it was assumed that rather than serving no useful purpose chronic idiopathic orofacial pain served a useful purpose? (3) Would current knowledge be sufficient to explain chronic idiopathic orofacial pain? The understanding defines chronic pain as being a centrally perceived event expressing the continual or episodic persistence of a level of peripheral and/or central neural activity above the pain threshold of a sensitized nervous system that is sufficient to maintain the sensitization. This ongoing neural activity may be associated with or independent of the neural activity that initiated the sensitization. In effect the nervous system is "bruised" and the "bruising" is being maintained (prodded) by the total neural activity of the system irrespective of its origin; the normal protective healing function of the nervous system, pain, continues its warning when the activity of the system activates the switch that is the pain threshold. The common clinical history of initial trauma and ongoing stress suggests that chronic pain might be thought of as an expression of post-traumatic stress. Treatment based on the presented understanding would aim to reduce and maintain total neural activity below the pain threshold level and ideally down to where the sensitization can be reduced or even resolved by neuroplastic processes, the level rather than the origin of neural activity being relevant to the pain mitigation. A review of chronic pain in the light of this understanding will provide the opportunity to formulate, test and refine new and existing strategies for its prevention and treatment, thereby offering hope to the millions of sufferers worldwide. PMID:22019262

Basser, David S

2011-10-21

206

Ischemic Tolerance  

Microsoft Academic Search

A brief period of cerebral ischemia confers transient tolerance to a subsequent ischemic challenge in the brain. This phenomenon of ischemic tolerance has been confirmed in various animal models of forebrain ischemia and focal cerebral ischemia. Since the ischemic tolerance afforded by preceding ischemia can bring about robust protection of the brain, the mechanism of tolerance induction has been extensively

Takaaki Kirino

2002-01-01

207

Effects of threatening information on interpersonal responses to pain  

Microsoft Academic Search

Emerging evidence indicates that meanings attributed to pain contribute to tolerance and coping among affected individuals. However, links between pain appraisals and coping responses have received little attention within a broader interpersonal context. In this experiment, effects of appraisal on pain tolerance and coping were examined in adult dyads. Eighty-six acquaintance\\/friend pairs were randomly assigned to the role of Participant

Todd Jackson; Xiting Huang; Hong Chen; Heath Phillips

2009-01-01

208

Hypersensitivity to pain in congenital blindness.  

PubMed

Vision is important for avoiding encounters with objects in the environment that may imperil physical integrity. We tested whether, in the absence of vision, a lower pain threshold would arise from an adaptive shift to other sensory channels. We therefore measured heat and cold pain thresholds and responses to suprathreshold heat stimuli in 2 groups of congenitally blind and matched normal-sighted participants. We also assessed detection thresholds for innocuous warmth and cold, and participants' attitude toward painful encounters in daily life. Our results show that, compared to sighted subjects, congenitally blind subjects have lower heat pain thresholds, rate suprathreshold heat pain stimuli as more painful, and have increased sensitivity for cold pain stimuli. Thresholds for nonpainful thermal stimulation did not differ between groups. The results of the pain questionnaires further indicated that blind subjects are more attentive to signals of external threats. These findings indicate that the absence of vision from birth induces a hypersensitivity to painful stimuli, lending new support to a model of sensory integration of vision and pain processing. PMID:24040972

Slimani, Hocine; Danti, Sabrina; Ricciardi, Emiliano; Pietrini, Pietro; Ptito, Maurice; Kupers, Ron

2013-10-01

209

Is the Deficit in Pain Inhibition in Fibromyalgia Influenced by Sleep Impairments?  

PubMed Central

It has been proposed that a deficit in inhibitory conditioned pain modulation (ICPM) underlies the pathophysiology of fibromyalgia (FM), but there is high variability in ICPM efficacy in this syndrome that remains poorly understood. Based on emerging data showing that age, anxiety, depression and sleep can modulate ICPM efficacy, the main objective of this study was to determine the clinical correlates of experimentally-induced pain perception in FM. Fifty FM patients and 39 healthy controls (HC) were tested. Anxiety, depression, sleep and FM symptoms were measured with questionnaires or interview-type scales. Experimental pain testing consisted of two tonic heat pain stimulations separated by a 2-minute cold pressor test (CPT). Thermal pain thresholds and tolerance were higher in HC compared to FM patients. Pain ratings during the CPT were lower in HC relative to FM patients. ICPM efficacy was stronger in HC compared to FM patients. Finally, sleep quality was the only factor significantly related to ICPM efficacy. To our knowledge, this is the first study to report this association in FM. Future studies will need to replicate this finding, to determine whether impaired sleep is primary or secondary to deficient pain inhibition, and to characterize the neurobiological mechanisms underlying this association.

Paul-Savoie, Emilie; Marchand, Serge; Morin, Melanie; Bourgault, Patricia; Brissette, Nathalie; Rattanavong, Vongmaly; Cloutier, Christian; Bissonnette, Alain; Potvin, Stephane

2012-01-01

210

Pain in Children: Neglected, Unaddressed and Mismanaged  

PubMed Central

Pain is one of the most misunderstood, under diagnosed, and under treated/untreated medical problems, particularly in children. One of the most challenging roles of medical providers serving children is to appropriately assess and treat their pain. New JCAHO regulations regard pain as “the fifth vital sign” and require caregivers to regularly assess and address pain. Pain being a personal experience, many different terms are used to describe different sensations. Assessment of pain in children is linked to their level of development. Children of the same age vary widely in their perception and tolerance of pain.

Mathews, Lulu

2011-01-01

211

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

PubMed Central

Background Functional abdominal pain syndrome (FAPS) has chronic unexplained abdominal pain and is similar to the psychiatric diagnosis of somatoform pain disorder. A patient with irritable bowel syndrome (IBS) also has chronic unexplained abdominal pain, and rectal hypersensitivity is observed in a majority of the patients. However, no reports have evaluated the visceral sensory function of FAPS precisely. We aimed to test the hypothesis that FAPS would show altered visceral sensation compared to healthy controls or IBS. The present study determined the rectal perceptual threshold, intensity of sensation using visual analogue scale (VAS), and rectal compliance in response to rectal balloon distention by a barostat in FAPS, IBS, and healthy controls. Methods First, the ramp distention of 40 ml/min was induced and the thresholds of discomfort, pain, and maximum tolerance (mmHg) were measured. Next, three phasic distentions (60-sec duration separated by 30-sec intervals) of 10, 15 and 20 mmHg were randomly loaded. The subjects were asked to mark the VAS in reference to subjective intensity of sensation immediately after each distention. A pressure-volume relationship was determined by plotting corresponding pressures and volumes during ramp distention, and the compliance was calculated over the linear part of the curve by calculating from the slope of the curve using simple regression. Results Rectal thresholds were significantly reduced in IBS but not in FAPS. The VAS ratings of intensity induced by phasic distention (around the discomfort threshold of the controls) were increased in IBS but significantly decreased in FAPS. Rectal compliance was reduced in IBS but not in FAPS. Conclusion An inconsistency of visceral sensitivity between lower and higher pressure distention might be a key feature for understanding the pathogenesis of FAPS.

2009-01-01

212

Positive Traits Linked to Less Pain through Lower Pain Catastrophizing.  

PubMed

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

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

2012-02-01

213

Experimental muscle pain impairs descending inhibition  

PubMed Central

In chronic musculoskeletal pain conditions, the balance between supraspinal facilitation and inhibition of pain shifts towards an overall decrease in inhibition. Application of a tonic painful stimulus results in activation of diffuse noxious inhibitory controls (DNIC). The aims of the present experimental human study were (1) to compare DNIC, evoked separately, by hypertonic saline (6%)-induced muscle pain (tibialis anterior) or cold pressor pain; (2) to investigate DNIC evoked by concomitant experimental muscle pain and cold pressor pain, and (3) to analyze for gender differences. Ten males and 10 age matched females participated in two sessions. In the first session unilateral muscle pain or unilateral cold pressor pain were induced separately; in the second session unilateral muscle pain and unilateral cold pressor pain were induced concomitantly. Pressure pain thresholds (PPT) were measured around the knee joint before, during, and after DNIC induction. Cold pressor pain increased PPT in both males and females with greater increases in males. Hypertonic saline-evoked muscle pain significantly increased PPT in males but not in females. When cold pressor and muscle pain were applied concomitantly the PPT increases were smaller when compared to the individual sessions. This study showed for the first time that two concurrent conditioning tonic pain stimuli (muscle pain and cold pressor pain) cause less DNIC compared with either of the conditioning stimuli given alone; and males showed greater DNIC than females. This may explain why patients with chronic musculoskeletal pain have impaired DNIC.

Arendt-Nielsen, Lars; Sluka, Kathleen A.; Nie, Hong Ling

2009-01-01

214

Threshold quantum cryptography  

SciTech Connect

We present the concept of threshold collaborative unitary transformation or threshold quantum cryptography, which is a kind of quantum version of threshold cryptography. Threshold quantum cryptography states that classical shared secrets are distributed to several parties and a subset of them, whose number is greater than a threshold, collaborates to compute a quantum cryptographic function, while keeping each share secretly inside each party. The shared secrets are reusable if no cheating is detected. As a concrete example of this concept, we show a distributed protocol (with threshold) of conjugate coding.

Tokunaga, Yuuki [NTT Information Sharing Platform Laboratories, NTT Corporation, 1-1 Hikari-no-oka, Yokosuka, Kanagawa 239-0847 (Japan); Division of Materials Physics, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan); Okamoto, Tatsuaki [NTT Information Sharing Platform Laboratories, NTT Corporation, 1-1 Hikari-no-oka, Yokosuka, Kanagawa 239-0847 (Japan); Imoto, Nobuyuki [Division of Materials Physics, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan)

2005-01-01

215

Anesthesia and pain control.  

PubMed

Successful anesthetic management of the critically ill patient requires familiarity with the pharmacologic properties of a variety of anesthetic drugs. An understanding of the altered physiology present in the critically ill allows an anesthetic regimen to be selected that prevents an anesthetic-induced decompensation. Pain should never go untreated because of a fear of causing excessive physiologic depression. There are numerous options available to control pain. A technique suitable in one instance may be unsuitable in another; for example, an animal that has a significant degree of respiratory compromise may not tolerate the additional respiratory insult associated with narcotic use. A local anesthetic technique may be preferred in this situation. Often a local technique is all that is necessary to control postoperative pain. Furthermore, if pain is controlled for the first 4 to 6 h post-insult, often no further analgesic drugs need to be administered. PMID:2688289

Bednarski, R M

1989-11-01

216

Elbow Pain  

MedlinePLUS

... find it difficult to describe what exactly brings on the pain. Causes Most elbow pain results from overuse injuries. Many sports, hobbies and jobs require repetitive hand, wrist or arm movements. Elbow pain may occasionally ...

217

Neuropathic Pain  

MedlinePLUS

... in Cart : 0 Resource Guide to Chronic Pain Medications & Treatments The Art of Pain Management What We Have Learned Going to the ER Communication Tools Pain Management Programs Videos Resources Glossary FAQs ...

218

Chronic Pain  

MedlinePLUS

... cause. Problems that cause chronic pain include Headache Low back strain Cancer Arthritis Pain from nerve damage Chronic pain usually cannot be cured. But treatments can help. They include medicines, acupuncture, electrical stimulation and surgery. Other treatments include psychotherapy, ...

219

Repeated noxious stimulation of the skin enhances cutaneous pain perception of migraine patients in-between attacks: clinical evidence for continuous sub-threshold increase in membrane excitability of central trigeminovascular neurons  

Microsoft Academic Search

Recent clinical studies showed that acute migraine attacks are accompanied by increased periorbital and bodily skin sensitivity to touch, heat and cold. Parallel pre-clinical studies showed that the underlying mechanism is sensitization of primary nociceptors and central trigeminovascular neurons. The present study investigates the sensory state of neuronal pathways that mediate skin pain sensation in migraine patients in between attacks.

Irit Weissman-Fogel; Elliot Sprecher; Yelena Granovsky; David Yarnitsky

2003-01-01

220

Depression, Pain, and Pain Behavior.  

ERIC Educational Resources Information Center

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…

Keefe, Francis J.; And Others

1986-01-01

221

Depression, Pain, and Pain Behavior  

Microsoft Academic Search

This study examined the degree to which depression predicted pain and pain behavior. The Beck Depression Inventory (BDI) was administered to 207 low back pain patients. Observations of pain behaviors during physical examination, ratings of pain, and measures of activity level and medication intake were taken on each patient. Regression analyses revealed that depression and physical findings were the most

Francis J. Keefe; Robert H. Wilkins; Wesley A. Cook; James E. Crisson; Lawrence H. Muhlbaier

1986-01-01

222

Risk Tolerance  

Microsoft Academic Search

This chapter provides an overview of the important role financial risk tolerance plays in shaping consumer financial decisions.\\u000a A review of normative and descriptive models of risk tolerance is provided. Additional discussion regarding the measurement\\u000a of risk tolerance is also presented. The chapter includes the presentation of a conceptual model of the principal factors\\u000a affecting financial risk tolerance with recommendations

John E. Grable

223

Modulations of pain sensations.  

PubMed

Representation of time may affect pain perception. We investigated a group of volunteers looking at different clocks while they were being exposed to the same intensity of pain in two experiments. In one case, they saw the actual time, while in the other, they gazed at a clock that made it seem like the stimulation was shortened, even though it wasn't. These results show that simply believing that time is on your side can make anything more bearable. The results were not influenced by the color of the clock (red or green), or the presence of indexes such as (sad or smiling) smileys. The effects were maximal for high intensities of stimulation (pain threshold +1°C) if the stimulation lasted for at least 25s but were absent if the stimulation was short (15 min). These results suggest that pain modulation by time context is mainly available for long and intense painful stimulations. The right upper and posterior parietal cortex may support this effect. These findings are discussed with regard to previous literature of pain modulations but also with regard to the concept of the "pain matrix", its inputs and the temporal dynamics of its constitutive responses. PMID:23040700

Peyron, R; Pomares, F-B; Faillenot, I; Barral, F-G; Laurent, B

2012-06-07

224

ELABORATION TOLERANCE  

Microsoft Academic Search

A formalism is elaboration tolerant to the extent that it is conve- nient to modify a set of facts expressed in the formalism to take into account new phenomena or changed circumstances. Representations of information in natural language have good elaboration tolerance when used with human background knowledge. Human-level AI will require representations with much more elaboration tolerance than those

John McCarthy

225

Automatic Threshold Circuit.  

National Technical Information Service (NTIS)

An automatic threshold circuit to establish a threshold that is a specified number of db above the input's rms frequency weighted noise value is described. The input is compared with the feedback threshold value, the result of which is coupled to a limite...

J. H. Bumgardner

1976-01-01

226

Threshold Concepts in Biochemistry  

ERIC Educational Resources Information Center

|Threshold concepts can be identified for any discipline and provide a framework for linking student learning to curricular design. Threshold concepts represent a transformed understanding of a discipline, without which the learner cannot progress and are therefore pivotal in learning in a discipline. Although threshold concepts have been…

Loertscher, Jennifer

2011-01-01

227

Intrathecal ziconotide: a review of its use in patients with chronic pain refractory to other systemic or intrathecal analgesics.  

PubMed

Ziconotide (Prialt(®)) is a synthetic conopeptide analgesic that acts by selectively antagonizing N-type voltage-gated calcium channels. Intrathecal ziconotide is the only non-opioid intrathecal analgesic that is FDA-approved for use in patients with treatment-refractory, chronic pain. The efficacy of intrathecal ziconotide was demonstrated in randomized, double-blind, placebo-controlled trials in patients with treatment-refractory noncancer-related pain or cancer- or AIDS-related pain. Across trials, ziconotide recipients had significantly greater reductions in pain intensity during ziconotide treatment than those receiving placebo (primary endpoint). At the end of the titration period, approximately one-sixth to one-third of patients with noncancer chronic pain and one-half with cancer- or AIDS-related pain who received ziconotide reached a pain response threshold (?30 % reduction in the pain intensity score). In ziconotide responders, analgesic effects were enduring, with some patients continuing treatment over extended periods. Across trials, the chief tolerability concerns in ziconotide recipients during the titration phase and during extended treatment were related to CNS adverse events. These were mostly of mild to moderate intensity, although serious adverse events were commonly attributed to ziconotide treatment, especially in trials with rapid ziconotide titration and that permitted higher dosages. In general, clinically important non-CNS adverse events were infrequent, and during the ziconotide titration phase, relatively few patients discontinued treatment because of adverse events. Ongoing research will assess various strategies for selecting patients for ziconotide treatment and for enhancing its efficacy and tolerability. At the present time, intrathecal ziconotide provides a treatment option for patients with severe, unremitting pain who have failed to respond to other intensive analgesic regimens. PMID:23999971

Sanford, Mark

2013-11-01

228

Sex differences in nociceptive withdrawal reflex and pain perception.  

PubMed

Experimentally induced pain often reveals sex differences, with higher pain sensitivity in females. The degree of differences has been shown to depend on the stimulation and assessment methods. Since sex differences in pain develop anywhere along the physiological and psychological components of the nociceptive system, we intended to compare the nociceptive flexion reflex (NFR) as a more physiological (spinal) aspect of pain procession to the verbal pain report of intensity and unpleasantness as the more psychological (cortical) aspect. Twenty female and twenty male healthy university students were investigated by use of nociceptive flexion reflex threshold (staircase method) after electrical stimulation of the N. suralis. Furthermore, we assessed supra-threshold reflex responses (latency, amplitude and area) by applying 10 stimuli 5 mA above reflex threshold. Following each stimulation, the subjects provided pain ratings of intensity and unpleasantness on a visual analogue scale. Females exhibited marked lower nociceptive flexion reflex thresholds than males, while the supra-threshold reflex response tailored to the individual reflex threshold did not show any significant differences. The verbal pain ratings, corrected for NFR threshold, were not found to differ significantly. The large sex differences in nociception that were present in NFR threshold but not in the pain ratings corroborate the hypothesis that spinal processes contribute substantially to sex differences in pain procession. PMID:16338828

Mylius, Veit; Kunz, Miriam; Schepelmann, Karsten; Lautenbacher, Stefan

2005-09-01

229

Development of mechanical and thermal nociceptive threshold testing devices in unrestrained birds (broiler chickens)  

Microsoft Academic Search

Behavioural signs of pain are difficult to quantify and interpret in animals. Nociceptive threshold testing is therefore a useful method for examining the perception and processing of noxious stimuli underlying pain states. Devices were developed to measure response thresholds to quantified, ramped mechanical and thermal nociceptive stimuli applied to the leg or keel of unrestrained birds. Up to 9N mechanical

B. Hothersall; G. Caplen; C. J. Nicol; P. M. Taylor; A. E. Waterman-Pearson; J. C. Murrell

2011-01-01

230

Electronic gaming as pain distraction.  

PubMed

The current study investigated whether active distraction reduces participants' experience of pain more than passive distraction during a cold pressor task. In the first experiment, 60 participants were asked to submerge their hand in cold (2°C) water for as long as they could tolerate. They did this with no distraction, and then with active (electronic gaming system) and passive (television) distraction, in randomly assigned order. Tolerance time, pain intensity ratings and task absorption ratings were measured for each condition. A second experiment attempted to control for participants' expectations about the effects of distraction on pain. Forty participants underwent the same experimental procedure, but were given verbal suggestions about the effects of distraction by the experimenter before each distraction condition. Participants in both experiments had a significantly higher pain tolerance and reported less pain with the active distraction compared with passive or no distraction. Participants reported being more absorbed, and were significantly more willing to do the task again when they had the active distraction compared with both passive distraction and no distraction. They also had more enjoyment, less anxiety and greater reduction in pain with active distraction than with passive distraction. There was no effect of suggestion. These experiments offer further support for the use of electronic games as a method of pain control. PMID:21369538

Jameson, Eleanor; Trevena, Judy; Swain, Nic

231

Psychophysical responses to a speech stressor: Correlation of plasma beta-endorphin levels at rest and after psychological stress with thermally measured pain threshold in patients with coronary artery disease  

Microsoft Academic Search

Objectives. We tested the hypothesis that psychological stress alters plasma levels of opioid peptides and that these plasma levels are related to pain perception in patients with coronary artery disease.Background. Public speaking psychological stress has previously been shown to be associated with silent ischemia.Methods. After instrumentation and a 30-min rest period, venous blood samples for beta-endorphin were obtained before and

David S. Sheps; Martha N. Ballenger; Guy E. De Gent; Rungroj Krittayaphong; Eileen Dittman; William Maixner; William McCartney; Robert N. Golden; Gary Koch; Kathleen C. Light

1995-01-01

232

Basic Mechanisms of Pain  

Microsoft Academic Search

Pain itself occurs in the central nervous system (CNS), while the peripheral nervous system reports on tissue damage via a\\u000a mechanical event, termed nociception, characterized by the discharge of high-threshold primary afferent fibers. Neuronal responses\\u000a in these peripheral fibers drive spinal cord activity and result in signals ascending to the brainstem and thalamus through\\u000a spinal cord tracts. It is from

Frank Willard

233

Fear-Avoidance Beliefs and Temporal Summation of Evoked Thermal Pain Influence Self-Report of Disability in Patients With Chronic Low Back Pain  

Microsoft Academic Search

\\u000a Introduction: Quantitative sensory testing has demonstrated a promising link between experimentally determined pain sensitivity and clinical pain. However, previous studies of quantitative sensory testing have not routinely considered the important influence of psychological factors on clinical pain. This study investigated whether measures of thermal pain sensitivity (temporal summation, first pulse response, and tolerance) contributed to clinical pain reports for patients

Steven Z. George; Virgil T. Wittmer; Roger B. Fillingim; Michael E. Robinson

2006-01-01

234

Cancer Pain  

Microsoft Academic Search

Cancer pain remains undertreated. Pain occurs in over three-quarters of cancer patients and remains one of the most feared\\u000a aspects of this illness despite the excellent therapies that are available. Cancer pain commonly results from tumor compressing\\u000a or invading soft tissue, bone, or nerves or from diagnostic or therapeutic endeavors. Optimal pain management involves determining\\u000a pain intensity, evaluating the etiology

Suzanne A. Nesbit

235

Correlation of gastric liquid emptying with various thresholds of sensation in healthy controls and patients with functional dyspepsia.  

PubMed

Our objective was to investigate the correlation between gastric emptying and sensation in patients with functional dyspepsia (FD). Thirty patients with FD and 15 controls were studied. Proximal gastric compliance and sensation thresholds were measured with a barostat, and gastric emptying was assessed for 70 min after the ingestion of 500 ml of water using real-time ultrasonography. Results were as follows. (1) Patients showed a significantly longer half-time of gastric emptying than controls (30.03 +/- 8.20 vs. 23.07 +/- 4.67 min; P < 0.001). The sensation thresholds were significantly lower in patients than in controls based not only on pressure but on volume. However, there was no difference in gastric compliance between patients and controls. (2) The half-time of gastric emptying was correlated with various thresholds of sensation based on the volume (perception, r = -0.52, P < 0.005; discomfort, r = -0.54, P < 0.005; pain, r = -0.58, P < 0.005; maximal tolerance, r = -0.42, P < 0.005). But there was no significant correlation between gastric emptying and sensation thresholds based on pressure. Delayed gastric emptying and/or gastric hypersensitivity are present in more than 50% of FD patients. The coexistence of these two abnormalities is more common than the single impairment. There is a correlation between gastric emptying and visceral sensation to gastric distention in patients with FD. PMID:15104356

Hou, Xiao-Hua; Li, Qixiang; Zhu, Liangru; Xie, Xiaoping; Chen, J D Z

2004-02-01

236

Predictors of postoperative movement and resting pain following total knee replacement.  

PubMed

This study determined preoperative predictors of movement and resting pain following total knee replacement (TKR). We hypothesized that younger patients with higher preoperative pain intensity, pain sensitivity, trait anxiety, pain catastrophizing, and depression would be more likely to experience higher postoperative movement pain than older patients with lower scores on these variables prior to surgery, and that predictors would be similar for resting pain. Demographics, analgesic intake, anxiety, depression, pain catastrophizing, resting pain, movement pain (ie, during active knee range of motion), and quantitative sensory tests were performed preoperatively on 215 participants scheduled for a unilateral TKR. On postoperative day 2, analgesic intake, resting pain, and movement pain were again assessed. Significant predictors of moderate or severe movement pain were higher preoperative movement pain, von Frey pain intensity, and heat pain threshold. People with severe movement pain preoperatively were 20 times more likely to have severe movement pain postoperatively. When the influence of preoperative movement pain was removed, depression became a predictor. Significant predictors of moderate to severe resting pain were higher preoperative resting pain, depression, and younger age. These results suggest that patients with higher preoperative pain and depression are more likely to have higher pain following TKR, and younger patients may have higher resting pain. Cutaneous pain sensitivity predicted movement pain but not resting pain, suggesting that mechanisms underlying movement pain are different from resting pain. Aggressive management of preoperative pain, pain sensitivity, and depression prior to surgery may facilitate postoperative recovery. PMID:22840570

Rakel, Barbara A; Blodgett, Nicole Petsas; Bridget Zimmerman, M; Logsden-Sackett, Nyla; Clark, Charles; Noiseux, Nicolas; Callaghan, John; Herr, Keela; Geasland, Katharine; Yang, Xiaoyan; Sluka, Kathleen A

2012-07-25

237

Muscle pain inhibits cutaneous touch perception.  

PubMed

The processing of noxious and non-noxious sensations differs between chronic pain syndromes, and we believe that studies of sensory processing in the presence of pain will help to clarify the aetiology of the conditions. Here we measured in humans the threshold-level mechanosensitivity in tonic experimental muscle pain. We found (1) that muscle pain induced by hypertonic saline reduced cutaneous threshold-level mechanosensitivity at the site of pain and at the mirror site in the contralateral face, (2) that this effect outlasted the sensation of pain, (3) that it was more pronounced when the painful area was reported to be large, and (4) that the loss of mechanosensitivity was greater in males than females. Comparing our findings to results obtained with other pain models, all classes of nociceptors do not seem to have the same effect on cutaneous mechanosensitivity. The observed threshold-level hypoesthesia is consistent with the hypothesis that the increased mechanical thresholds found in clinic cases of temporomandibular disorders and cervicobrachialgia are a direct result of the activation of muscle nociceptors. PMID:11376905

Stohler, C S; Kowalski, C J; Lund, J P

2001-06-01

238

Nicotine is a pain reliever in trauma- and chemotherapy-induced neuropathy models.  

PubMed

Chemotherapy-induced neuropathies are widespread disorders evoked by characteristic damage of the nervous system. Sensory alterations, as paresthesia and dysesthesia, and severe pain are disabling side effects that altered quality of life, leading to therapy discontinuation. These kind of neuropathies are extremely difficult to treat and actual therapies are generally palliative. A great deal of interest has evolved around the relevance of nicotinic receptors as target for chronic pain therapy. Selective receptor subtype modulators have been described as active in pain relief. On the other hand, the profile of nicotine as such, or delivered by tobacco smoke, is a matter of debate since the analgesic properties may be impaired by receptor desensitization and tolerance. Nicotine acute effect on nociceptive threshold was evaluated in the Chronic Constriction Injury model in comparison with neuropathies induced by chemotherapeutic agents. Fourteen days after nerve injury, intraperitoneally administered nicotine (0.5-1.5 mg/kg) reduced hypersensitivity to noxious and non-noxious stimuli. Painful neuropathic state was alternatively established by the intravenously injection of the antiviral agent dideoxycytidine (25 mg/kg). Nicotine significantly reduced antiviral-dependent alterations of the nociceptive threshold. Moreover, nicotine decreased neuropathic pain induced by repeated intraperitoneal administration of the anticancer agent oxaliplatin (2.4 mg/kg), lowering the hypersensitivity to mechanical and thermal stimuli. In conclusion, intraperitoneal nicotine administration controls neuropathic pain evoked by traumatic or toxic nervous system alterations. These results support the nAChR modulation as a possible therapeutic approach to the complex, undertreated chemotherapy-induced neuropathies. PMID:23648560

Di Cesare Mannelli, Lorenzo; Zanardelli, Matteo; Ghelardini, Carla

2013-05-03

239

Bayesian Threshold Estimation  

ERIC Educational Resources Information Center

|Bayesian estimation of a threshold time (hereafter simply threshold) for the receipt of impulse signals is accomplished given the following: 1) data, consisting of the number of impulses received in a time interval from zero to one and the time of the largest time impulse; 2) a model, consisting of a uniform probability density of impulse time…

Gustafson, S. C.; Costello, C. S.; Like, E. C.; Pierce, S. J.; Shenoy, K. N.

2009-01-01

240

Hierarchical Threshold Secret Sharing  

Microsoft Academic Search

We consider the problem of threshold secret sharing in groups with hierarchical structure. In such settings, the secret is shared among a group of participants that is partitioned into levels. The access structure is then determined by a sequence of threshold requirements: a subset of participants is authorized if it has at least k0 members from the highest level, as

Tamir Tassa

2004-01-01

241

Orofacial Pain  

MedlinePLUS

... Neck, shoulder or back pain Dizziness ?xml:namespace> Sleep disorders ; If you have gone through treatment and still experience orofacial pain, you may have a sleep disorder, such as bruxism, or a sleep-related breathing ...

242

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 ...

243

Hip Pain  

MedlinePLUS

... 0/1807/0.html. Accessed May 13, 2013. Anderson BC. Evaluation of the adult with hip pain. ... www.uptodate.com/home. Accessed May 13, 2013. Anderson BC. Patient information: Hip pain (Beyond the basics). ...

244

Neck Pain  

MedlinePLUS

... over-the counter medicine, such as acetaminophen or ibuprofen, to relieve pain, and apply heat to the ... an injury. Use anti-inflammatory medicines, such as ibuprofen and aspirin, to relieve pain and discomfort, and ...

245

Effects of Pain Acceptance and Pain Control Strategies on Physical Impairment in Individuals With Chronic Low Back Pain  

Microsoft Academic Search

Psychosocial treatments for chronic pain are effective. There is a need, however, to understand the processes involved in determining how these treatments contribute to behavior change. Control and acceptance strategies represent two potentially important processes involved in treatment, although they differ significantly in approach. Results from laboratory-based studies suggest that acceptance-oriented strategies significantly enhance pain tolerance and behavioral persistence, compared

Kevin E. Vowles; Daniel W. McNeil; Richard T. Gross; Michael L. McDaniel; Angela Mouse; Mick Bates; Paula Gallimore; Cindy McCall

2007-01-01

246

Heterotopic noxious conditioning stimulation (HNCS) reduced the intensity of spontaneous pain, but not of allodynia in painful peripheral neuropathy.  

PubMed

In 15 patients with painful peripheral neuropathy and dynamic mechanical allodynia, the influence of spontaneous ongoing neuropathic pain on pain sensitivity in a remote pain-free area was examined, as was the influence of ischemia-induced heterotopic noxious conditioning stimulation (HNCS) on the intensity of ongoing pain and brush-evoked allodynia. In addition, the modulating effect of HNCS on pain sensitivity in a pain-free area was investigated. Pain thresholds to pressure and heat as well as the sensitivity to suprathreshold pressure- and heat pain were assessed in the pain-free area. Dynamic mechanical allodynia was induced by a recently developed semi-quantitative brushing technique and the patients continuously rated the intensity of the allodynia using a computerized visual analogue scale (VAS). The total brush-evoked pain intensity was calculated as the area under the VAS curve. At baseline, no significant difference in pain sensitivity was found between patients and their healthy controls in the pain-free area, indicating a lack of activation of pain modulatory systems from the spontaneous pain. Compared to baseline, the patients rated the ongoing neuropathic pain intensity significantly lower during the HNCS-procedure (p<0.05). In contrast, there was no influence from HNCS on the total brush-evoked pain intensity. In the pain-free area higher pressure pain thresholds were demonstrated during conditioning stimulation in patients and controls alike (p<0.01). In controls only, a significantly higher heat pain threshold was found during the HNCS-procedure (p<0.01). The main finding of the present study was that HNCS altered differentially spontaneous and brush-provoked pain in patients with painful peripheral neuropathy. PMID:16889998

Tuveson, Birgitta; Leffler, Ann-Sofie; Hansson, Per

2006-08-04

247

Prayer and pain: the mediating role of positive re-appraisal.  

PubMed

The present study explored in a sample of Flemish pain patients the role of prayer as a possible individual factor in pain management. The focus on prayer as a personal religious factor fits with the current religious landscape in Western-Europe where personal religious factors are more important than organizational dimensions of religion. Our study is framed in the transactional theory of stress and coping by testing first, whether prayer was related with pain severity and pain tolerance and second, whether cognitive positive re-appraisal was a mediating mechanism in the association between prayer and pain. We expected that prayer would be related to pain tolerance in reducing the impact of the pain on patient's daily life, but not necessarily to pain severity. A cross-sectional questionnaire design was adopted in order to measure demographics, prayer, pain outcomes (i.e., pain severity and pain tolerance), and cognitive positive re-appraisal. Two hundred and two chronic pain (CP) patients, all members of a Flemish national patients association, completed the questionnaires. Correlational analyses showed that prayer was significantly related with pain tolerance, but not with pain severity. However, ancillary analyses revealed a moderational effect of religious affiliation in the relationship between prayer and pain severity as well as pain tolerance. Furthermore, mediation analysis revealed that cognitive positive re-appraisal was indeed an underlying mechanism in the relationship between prayer and pain tolerance. This study affirms the importance to distinguish between pain severity and pain tolerance, and indicates that prayer can play a role in pain management, especially for religious pain patients. Further, the findings can be framed within the transactional theory of stress and coping as the results indicate that positive re-appraisal might be an important underlying mechanism in the association between prayer and pain. PMID:21516338

Dezutter, Jessie; Wachholtz, Amy; Corveleyn, Jozef

2011-04-23

248

Cancer Pain  

Microsoft Academic Search

Pain is a significant problem in cancer and there are many barriers to adequate pain control. Cancer-related pain is common\\u000a and has a destructive impact on a patient’s quality of life. Physicians need to understand better the appropriate use of opioid\\u000a and nonopioid analgesics and to consider other therapeutic options when appropriate. This chapter discusses the mechanisms\\u000a of pain underlying

Sebastiano Mercadante

249

The role of threat expectancy in attentional bias and thermal pain perception in healthy individuals.  

PubMed

The influence of threat expectancy upon attentional biases for pain-related information and pain thresholds was explored in healthy participants. Participants were randomized to receive either threatening (n = 32) or nonthreatening (n = 31) information regarding an upcoming computerized task assessing cold and heat pain thresholds. Participants receiving threatening information were more worried about the pain task and, relative to those receiving nonthreatening information, showed attentional bias toward sensory-pain words. No between-group differences were found in terms of cold and heat pain thresholds. These results show that the type of information participants receive can influence their attentional processes and emotional concerns. PMID:23511382

Schoth, Daniel; Yu, Karen; Liossi, Christina

2013-03-19

250

Management of breakthrough pain due to cancer  

PubMed Central

Breakthrough pain is defined as the transient exacerbation of pain occurring in a patient with otherwise stable, persistent pain. It is estimated to affect over 50% of patients, particularly those with moderate to severe background pain. Breakthrough pain is one of the most difficult pain syndromes to treat. There are several types of breakthrough cancer pain: incidental type involves flares of pain associated with movement or activity; idiopathic type is transitory pain unrelated to a specific activity; and in end-of-dose failure pain occurs when blood levels of medications fall below an analgesic threshold at the end of a dosing interval. Persistent and breakthrough pain are distinct components of cancer pain and require separate management. Successful management of breakthrough pain may require a combination of pharmacological and non-pharmacological treatment strategies. Supplemental analgesia, known as rescue medication, is a common pharmacological treatment option. Breakthrough pain is treated with supplemental short-acting opioid use, as needed, e.g. short-acting morphine, intranasal fentanyl and buccal tablets of fentanyl.

2013-01-01

251

Distortion tolerant correlation filter design.  

PubMed

This paper introduces a computationally efficient algorithm for synthesis of a distortion tolerant correlation filter and associated threshold, denoted collectively as the enhanced matched filter (EMF). Application areas of EMF include imagery based automatic target detection and recognition and biometrics. The EMF is synthesized from a set of training images characterizing the target of interest within the expected distortion range. A distinguishing feature of EMF is the ascribed threshold, which is a byproduct of the filter computation process and does not rely on nontarget trainers. The EMF performance is compared to that of the synthetic discriminant function using realistic test scenarios. PMID:23669663

Heidary, Kaveh

2013-04-20

252

Mothers’ modeling influences children's pain during a cold pressor task  

Microsoft Academic Search

We set out to determine whether observing one's mother's reaction during a cold pressor test changes ratings of pain threshold, pain intensity, and observed pain-related facial behavior during a cold pressor test, using a Repeated Measures Mixed Factorial design in the setting of the Psychology Department, Dalhousie University, Halifax, Canada. The participants were: 96 mothers (mean age 41 years,) and

Julie E Goodman; Patrick J McGrath

2003-01-01

253

Treatment of painful peripheral neuropathy.  

PubMed

Treatment of neuropathic pain is the primary focus of management for many patients with painful peripheral neuropathies. Antidepressants and anticonvulsants are the two medication classes most widely studied and represent first-line agents in the management of neuropathic pain. The number of pharmacologic agents and interventional procedures that have shown effectiveness in the treatment of neuropathic pain continues to expand. Pain management should begin with a concerted effort to identify the etiology of the neuropathy, because directed therapy can help alleviate the symptoms. When initiating pharmacotherapy for neuropathic pain, one must individualize treatment and choose an agent that is likely to be tolerated, because adverse events are common for many of these agents. Neuropathic pain management remains challenging because of heterogeneous responses between individuals and the fact that pain relief is rarely complete. However, monotherapy with a well-chosen agent or rational polypharmacy that combines medications with different mechanisms of action will benefit a majority of patients with neuropathic pain. PMID:19078690

Wolfe, Gil I; Hotz, Susan E; Barohn, Richard J

2002-12-01

254

Salt Tolerance  

PubMed Central

Studying salt stress is an important means to the understanding of plant ion homeostasis and osmo-balance. Salt stress research also benefits agriculture because soil salinity significantly limits plant productivity on agricultural lands. Decades of physiological and molecular studies have generated a large body of literature regarding potential salt tolerance determinants. Recent advances in applying molecular genetic analysis and genomics tools in the model plant Arabidopsis thaliana are shading light on the molecular nature of salt tolerance effectors and regulatory pathways.

Xiong, Liming; Zhu, Jian-Kang

2002-01-01

255

Lornoxicam efficacy in acute pain (LEAP) trial.  

PubMed

Parenteral non-steroidal anti-inflammatory drugs (NSAIDs) are useful agents in the treatment of postoperative pain and other acute traumatic painful conditions such as fractures. Clinical trials with lornoxicam, an oxicam derivative, document its efficacy as a potent analgesic with excellent anti-inflammatory properties in painful and or/inflammatory conditions including postoperative pain and arthritic conditions. However, there is no documentation of the efficacy and tolerability of intravenous lornoxicam in Indian patients with acute painful conditions such painful traumatic conditions requiring hospitalisation and parenteral analgesics. The present study was undertaken to evaluate the efficacy and tolerability of intravenous lornoxicam in Indian patients with postoperative pain or other acute painful traumatic conditions requiring hospitalisation and parenteral analgesia in in-office practice conditions. In this multicentric, prospective, open, non-comparative phase IV, postmarketing surveillance study patients admitted in the nursing home for either postoperative pain or painful conditions requiring hospitalisation and parenteral analgesia were enrolled in the study after obtaining their informed consent. Of the 161 patients fulfilling the selection criteria, 148 met the selection criteria and were included in the efficacy analysis. Patients were treated with intravenous lornoxicam 8 mg twice or three times daily as required for up to 3 days. Efficacy variables included changes in severity of pain scores compared to baseline values, onset of pain relief and overall global efficacy. Tolerability was assessed through monitoring of treatment-emergent adverse events, physical examination, assessments of vital signs, and overall global assessment of tolerability. Results indicated that within 1 hour of administration of intravenous lornoxicam, the mean scores of pain severity were reduced by 39.46% and by 6 hours, there was a further 52% reduction in the mean scores. Therapy with intravenous lornoxicam was associated with a faster onset of action with 15.4% patients reporting pain relief within 10 minutes and 55.9% patients within 10 to 30 minutes. Overall, global assessment of efficacy was rated as good to excellent in 95.3% of the patients. Therapy with intravenous lornoxicam was well tolerated with only 5 patients reporting adverse events such as headache (n=3) and gastritis (n=1) of mild to moderate intensity but transient. Overall, global tolerability was rated as good to excellent in 98.4% of the total cases and fair in only 1.6% of the cases. In conclusion, the results of the present study indicate that intravenous lornoxicam is a potent NSAID with an optimal efficacy/toxicity ratio and thus could be a suitable therapeutic option in the management of patients with painful traumatic conditions requiring parenteral NSAIDs and hospitalisation. PMID:19370957

Sharma, Akhilesh; Pingle, Anup; Baliga, Vidyagauri P

2008-12-01

256

Placebo manipulations reduce hyperalgesia in neuropathic pain.  

PubMed

Several studies have shown that placebo analgesia effects can be obtained in healthy volunteers, as well as patients suffering from acute postoperative pain and chronic pain conditions such as irritable bowel syndrome. However, it is unknown whether placebo analgesia effects can be elicited in chronic pain conditions with a known pathophysiology such as a nerve injury. Nineteen patients who had developed neuropathic pain after thoracotomy were exposed to a placebo manipulation in which they received either open or hidden administrations of lidocaine. Before the treatment, the patients rated their levels of spontaneous pain and expected pain and completed a questionnaire on their emotional feelings (Positive Affect Negative Affect Schedule) and went through quantitative sensory testing of evoked pain (brush and cold allodynia, heat pain tolerance, area of pinprick hyperalgesia, wind-up-like pain after pinprick stimulation). The placebo manipulation significantly reduced the area of pinprick hyperalgesia (P=.027), and this placebo effect was significantly related to low levels of negative affect (P=.008; R(2)=0.362) but not to positive affect or expected pain levels. No placebo effect was observed in relation to spontaneous pain or evoked pain, which is most likely due to low pain levels resulting in floor effects. This is the first study to demonstrate a placebo effect in neuropathic pain. The possible mechanisms underlying the placebo effects in hyperalgesia are discussed, and implications for treatment are outlined. PMID:22503337

Petersen, Gitte Laue; Finnerup, Nanna Brix; Nørskov, Kathrine Næsted; Grosen, Kasper; Pilegaard, Hans K; Benedetti, Fabrizio; Price, Donald D; Jensen, Troels Staehelin; Vase, Lene

2012-04-13

257

Central pain in multiple sclerosis - sensory abnormalities.  

PubMed

Many patients with multiple sclerosis (MS) develop central neuropathic pain (CP). In the present study somatosensory abnormalities have been analysed in detail in 62 patients with MS and CP (42 women, 20 men; mean age 52 years) and in a control group of 10 women and 6 men (mean age 47 years) with MS and sensory symptoms, but without pain. Assessment included clinical testing and quantitative methods (QST) for the measurement of perception thresholds for touch, vibration, and temperatures. All CP patients except two (97%) had abnormal thresholds for innoxious and/or noxious temperatures, compared to 81% in the control group (p<0.05). There was a tendency towards the opposite regarding sensibility to touch, which was decreased in 66% vs. 87% (n.s.), vibration (55% vs. 81%; n.s.) and to joint movement (32% vs. 62%; p<0.04). Comparisons between painful and non-painful regions showed both the absolute threshold values and the index values to be significantly more abnormal, in the CP regions, for warmth (p<0.001), cold (p<0.05), difference limen (innoxious warmth and cold, p<0.01), cold pain (p<0.01) and heat pain/cold pain combined (p<0.001). Also the comparisons between regions with central pain and regions with sensory symptoms in the controls showed significantly more abnormal thresholds in the CP patients for warmth (p<0.05), cold (p<0.01), difference limen (innoxious warmth and cold, p<0.01) and heat pain/cold pain combined (p<0.001). The results support the general hypothesis that only patients who have lesions affecting the spinothalamo-cortical pathways run the risk of developing central pain. PMID:19359204

Osterberg, A; Boivie, J

2009-04-08

258

Quantum threshold group signature  

NASA Astrophysics Data System (ADS)

In most situations, the signer is generally a single person. However, when the message is written on behalf of an organization, a valid message may require the approval or consent of several persons. Threshold signature is a solution to this problem. Generally speaking, as an authority which can be trusted by all members does not exist, a threshold signature scheme without a trusted party appears more attractive. Following some ideas of the classical Shamir’s threshold signature scheme, a quantum threshold group signature one is proposed. In the proposed scheme, only t or more of n persons in the group can generate the group signature and any t - 1 or fewer ones cannot do that. In the verification phase, any t or more of n signature receivers can verify the message and any t - 1 or fewer receivers cannot verify the validity of the signature.

Yang, Yuguang; Wen, Qiaoyan

2008-10-01

259

Efficacy and Tolerability of Conventional Nimesulide Versus Beta-Cyclodextrin Nimesulide in Patients with Pain After Surgical Dental Extraction: A Multicenter, Prospective, Randomized, Double-Blind, Double-Dummy Study  

Microsoft Academic Search

Background: Pain following extraction of an impacted third molar is widely used to assess analgesic efficacy, especially that of a single dose of a drug. The analgesic activity of conventional nimesulide (CN) has been documented in a variety of types of acute and chronic pain. Beta-cyclodextrin nimesulide (BN) is a new formulation in which nimesulide is included in a cyclodextrin

Mildred Bocanegra; Alberto Seijas; Maria González Yibir??n

2003-01-01

260

Prediction of postoperative pain after percutaneous nephrolithotomy: can preoperative experimental pain assessment identify patients at risk?  

PubMed

Postoperative pain remains a significant problem and the individual variance in postoperative pain is not fully understood. In recent years, there has been focus on identifying risk factors predicting patients with high postoperative pain intensity or consumption of analgesics, which may facilitate an improvement in rehabilitation. This study evaluates the relationship between preoperative experimental pain assessment and postoperative pain and opioid consumption. Forty-four patients with uni- or bilateral kidney stone disease scheduled for percutaneous nephrolithotomy were included. The preoperative pain thresholds were measured using electrical (single and 5 repeated) and pressure pain stimulation over the flank bilaterally (stone-side = operation side and control-side = non-operation side). Postoperative pain scores were recorded on a numerical rating scale and analgesic consumption was registered. The responses to repeated electrical stimuli (temporal summation) were preoperatively increased on the stone-side compared to the control-side (P = 0.016). Preoperative electrical pain thresholds from the control-side correlated inversely with postoperative opioid consumption (single stimuli: ? = -0.43, P < 0.01; repeated stimuli: ? = -0.45, P < 0.005). This correlation was more pronounced for the 22 patients with unilateral renal calculi (single stimuli: ? = -0.54, P < 0.02; repeated stimuli: ? = -0.58, P < 0.01). There were no other correlations between the preoperative sensory tests and postoperative pain or opioid consumption. This study showed a correlation between the preoperative electrical pain thresholds on the control-side and postoperative opioid consumption after percutaneous nephrolithotomy. Preoperative measurement of the electrical pain thresholds may, therefore, be useful as a screening tool to identify patients at high risk of postoperative pain. PMID:23503880

Pedersen, Katja Venborg; Olesen, Anne Estrup; Osther, Palle Jørn Sloth; Arendt-Nielsen, Lars; Drewes, Asbjørn Mohr

2013-02-08

261

Hierarchical Threshold Secret Sharing  

Microsoft Academic Search

We consider the problem of threshold secret sharing in groups with hierarchical structure. In such settings, the secret is\\u000a shared among a group of participants that is partitioned into levels. The access structure is then determined by a sequence\\u000a of threshold requirements: a subset of participants is authorized if it has at least k0 0 members from the highest level,

Tamir Tassa

2007-01-01

262

Pain Genes  

PubMed Central

Pain, which afflicts up to 20% of the population at any time, provides both a massive therapeutic challenge and a route to understanding mechanisms in the nervous system. Specialised sensory neurons (nociceptors) signal the existence of tissue damage to the central nervous system (CNS), where pain is represented in a complex matrix involving many CNS structures. Genetic approaches to investigating pain pathways using model organisms have identified the molecular nature of the transducers, regulatory mechanisms involved in changing neuronal activity, as well as the critical role of immune system cells in driving pain pathways. In man, mapping of human pain mutants as well as twin studies and association studies of altered pain behaviour have identified important regulators of the pain system. In turn, new drug targets for chronic pain treatment have been validated in transgenic mouse studies. Thus, genetic studies of pain pathways have complemented the traditional neuroscience approaches of electrophysiology and pharmacology to give us fresh insights into the molecular basis of pain perception.

Foulkes, Tom; Wood, John N.

2008-01-01

263

Increment Thresholds on Black Bars.  

National Technical Information Service (NTIS)

Under conditions that isolate rod vision, increment thresholds were measured on black bars of various widths, and compared to the increment threshold measured on a homogeneously illuminated field without the bar. Thresholds were found to be elevated in th...

D. Y. Teller

1968-01-01

264

Is the pain in chronic pancreatitis of neuropathic origin? Support from EEG studies during experimental pain  

Microsoft Academic Search

AIM: To prove the hypothesis that patients with chronic pancreatitis would show increased theta activity during painful visceral stimulation. METHODS: Eight patients and 12 healthy controls underwent an experiment where the esophagus was electrically stimulated at the pain threshold using a nasal endoscope. The electroencephalogram (EEG) was recorded from 64 surface electrodes and \\

Asbjørn M Drewes; Maciej Gratkowski; Saber AK Sami; Georg Dimcevski; Peter Funch-Jensen; Lars Arendt-Nielsen

2008-01-01

265

Tactile, thermal and pain sensibility in burned patients with and without chronic pain and paresthesia problems  

Microsoft Academic Search

Abnormal return of cutaneous sensibility is common after burn injuries and many patients complain of painful and\\/or paresthetic sensations in their healed wounds. However, little is known about the exact nature and severity of these problems. The present study was designed to provide a quantitative evaluation of the cutaneous sensibility in burned patients. Tactile, thermal and pain thresholds were measured

Annie Malenfant; Robert Forget; Rhonda Amself; Jacques Papillon; Jean-Yves Frigon; Manon Choinièrea

1998-01-01

266

Neuropathic Pain  

PubMed Central

Neuropathic pain is triggered by lesions to the somatosensory nervous system that alter its structure and function so that pain occurs spontaneously and responses to noxious and innocuous stimuli are pathologically amplified. The pain is an expression of maladaptive plasticity within the nociceptive system, a series of changes that constitute a neural disease state. Multiple alterations distributed widely across the nervous system contribute to complex pain phenotypes. These alterations include ectopic generation of action potentials, facilitation and disinhibition of synaptic transmission, loss of synaptic connectivity and formation of new synaptic circuits, and neuroimmune interactions. Although neural lesions are necessary, they are not sufficient to generate neuropathic pain; genetic polymorphisms, gender, and age all influence the risk of developing persistent pain. Treatment needs to move from merely suppressing symptoms to a disease-modifying strategy aimed at both preventing maladaptive plasticity and reducing intrinsic risk.

Costigan, Michael; Scholz, Joachim; Woolf, Clifford J.

2009-01-01

267

Myofascial Pain  

Microsoft Academic Search

\\u000a \\u000a \\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a \\u000a Myofascial pain should be considered in patients with localized pain complaints without arthritic or neuropathic features.\\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a \\u000a Myofascial pain syndrome should not be diagnosed in patients with no physical findings. Myofascial pain requires the presence\\u000a of a taut band and muscular trigger points.\\u000a \\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a \\u000a Active trigger points refer pain in predictable patterns.\\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a \\u000a Treatment of myofascial pain focuses on

Dawn A. Marcus

268

Elbow pain  

MedlinePLUS

... common causes of elbow tendinitis are gardening, playing baseball, using a screwdriver, or overusing your wrist and ... involve: Antibiotics Corticosteroid shots Pain medicine Physical therapy Surgery (last resort)

269

Mitochondrial threshold effects.  

PubMed Central

The study of mitochondrial diseases has revealed dramatic variability in the phenotypic presentation of mitochondrial genetic defects. To attempt to understand this variability, different authors have studied energy metabolism in transmitochondrial cell lines carrying different proportions of various pathogenic mutations in their mitochondrial DNA. The same kinds of experiments have been performed on isolated mitochondria and on tissue biopsies taken from patients with mitochondrial diseases. The results have shown that, in most cases, phenotypic manifestation of the genetic defect occurs only when a threshold level is exceeded, and this phenomenon has been named the 'phenotypic threshold effect'. Subsequently, several authors showed that it was possible to inhibit considerably the activity of a respiratory chain complex, up to a critical value, without affecting the rate of mitochondrial respiration or ATP synthesis. This phenomenon was called the 'biochemical threshold effect'. More recently, quantitative analysis of the effects of various mutations in mitochondrial DNA on the rate of mitochondrial protein synthesis has revealed the existence of a 'translational threshold effect'. In this review these different mitochondrial threshold effects are discussed, along with their molecular bases and the roles that they play in the presentation of mitochondrial diseases.

Rossignol, Rodrigue; Faustin, Benjamin; Rocher, Christophe; Malgat, Monique; Mazat, Jean-Pierre; Letellier, Thierry

2003-01-01

270

[Relations and variability of the stapedial reflex threshold and psychoacoustic discomfort threshold].  

PubMed

Ten normal hearing subjects were subjected to repeated measurement of the stapedial reflex threshold (RT) and loudness discomfort threshold (DT) during five separate sessions. On the average DT was 4.8 dB higher than the RT. The sessions did not affect the intra-individual variance of either threshold. A regression analysis demonstrated that a significant linear relationship exists between RT and DT. However, DT may be lower than RT when the latter is shifted towards its upper variance boundary. Hence, RT and DT are not equivalent as indicators of the upper limit of loudness tolerance; since DT revealed a low intra-subject variance, such a psychoacoustic measurement may be reliably used for clinical purposes. PMID:1776435

Prosser, S; Rosignoli, M

1991-01-01

271

Near threshold fatigue testing  

NASA Astrophysics Data System (ADS)

Measurement of the near-threshold fatigue crack growth rate (FCGR) behavior provides a basis for the design and evaluation of components subjected to high cycle fatigue. Typically, the near-threshold fatigue regime describes crack growth rates below approximately 10(exp -5) mm/cycle (4 x 10(exp -7) inch/cycle). One such evaluation was recently performed for the binary alloy U-6Nb. The procedures developed for this evaluation are described in detail to provide a general test method for near-threshold FCGR testing. In particular, techniques for high-resolution measurements of crack length performed in-situ through a direct current, potential drop (DCPD) apparatus, and a method which eliminates crack closure effects through the use of loading cycles with constant maximum stress intensity are described.

Freeman, D. C.; Strum, M. J.

1993-01-01

272

Ovarian hormones and pain response: A review of clinical and basic science studies  

Microsoft Academic Search

Background: Most clinical pain disorders are more common in women than in men, particularly during the peak reproductive years. This suggests that fluctuations in the ovarian hormones encountered during the female menstrual cycle may increase pain response.Objectives: This article examined whether pain severity and experimental pain thresholds vary during the phases of the menstrual cycle in women with and without

Vincent T. Martin

2009-01-01

273

Pain Genes  

Microsoft Academic Search

Pain, which afflicts up to 20% of the population at any time, provides both a massive therapeutic challenge and a route to understanding mechanisms in the nervous system. Specialised sensory neurons (nociceptors) signal the existence of tissue damage to the central nervous system (CNS), where pain is represented in a complex matrix involving many CNS structures. Genetic approaches to investigating

Tom Foulkes; John N. Wood

2008-01-01

274

Knee Pain  

MedlinePLUS

... when the triangular bone (patella) that covers the front of your knee slips out of place, usually to the outside of your knee. In some cases, the kneecap may stay displaced and you'll be able to see the dislocation. Hip or foot pain. If you have hip or foot pain, you ...

275

Heel Pain  

MedlinePLUS

... pronation may also contribute to injury to the hip, knee, and lower back. Achilles tendinitis: Pain at the back of the heel is associated ... of steps can be taken to avoid heel pain and accompanying afflictions: Wear shoes that fit well—front, back, and sides—and have shock-absorbent soles, ...

276

Intolerant tolerance.  

PubMed

The Hyde Amendment and Roman Catholic attempts to put restrictions on Title X funding have been criticized for being intolerant. However, such criticism fails to appreciate that there are two competing notions of tolerance, one focusing on the limits of state force and accepting pluralism as unavoidable, and the other focusing on the limits of knowledge and advancing pluralism as a good. These two types of tolerance, illustrated in the writings of John Locke and J.S. Mill, each involve an intolerance. In a pluralistic context where the free exercise of religion is respected, John Locke's account of tolerance is preferable. However, it (in a reconstructed form) leads to a minimal state. Positive entitlements to benefits like artificial contraception or nontherapeutic abortions can legitimately be resisted, because an intolerance has already been shown with respect to those that consider the benefit immoral, since their resources have been coopted by taxation to advance an end that is contrary to their own. There is a sliding scale from tolerance (viewed as forbearance) to the affirmation of communal integrity, and this scale maps on to the continuum from negative to positive rights. PMID:8051515

Khushf, G

1994-04-01

277

Religious Tolerance.  

ERIC Educational Resources Information Center

|This theme issue looks at three issues of religious tolerance. The first article examines a case recently decided by the United States Supreme Court on student-led prayers at school events. The second article explores the persecution suffered by members of the Mormon religion during the 19th century. The final article looks at Martin Luther and…

Martz, Carlton

2000-01-01

278

Pain perception and nonsuicidal self-injury: a laboratory investigation.  

PubMed

People who engage in self-injurious behaviors such as cutting and burning may have altered pain perception. Using a community sample, we examined group differences in pain threshold and pain endurance between participants who self-injured and control participants who were exposed to pressure pain applied to the finger. Participants who self-injured had higher pain thresholds (time to report pain) and endured pain for longer than control participants. Among participants who self-injured, those with longer histories of self-injury had higher pain thresholds. Duration of self-injury was unrelated to pain endurance. Instead, greater pain endurance was predicted by higher levels of introversion and neuroticism and by more negative beliefs about one's self-worth. A highly self-critical cognitive style was the strongest predictor of prolonged pain endurance. People who self-injure may regard suffering and pain as something that they deserve. Our findings also have implications for understanding factors that might be involved in the development and maintenance of self-injury. PMID:22448633

Hooley, Jill M; Ho, Doreen T; Slater, Joshua; Lockshin, Amanda

2010-07-01

279

Oral tolerance  

PubMed Central

Summary The gut-associated lymphoid tissue is the largest immune organ in the body and is the primary route by which we are exposed to antigens. Tolerance induction is the default immune pathway in the gut, and the type of tolerance induced relates to the dose of antigen fed: anergy/deletion (high dose) or regulatory T-cell (Treg) induction (low dose). Conditioning of gut dendritic cells (DCs) by gut epithelial cells and the gut flora, which itself has a major influence on gut immunity, induces CD103+ retinoic acid-dependent DC that induces Tregs. A number of Tregs are induced at mucosal surfaces. Th3 type Tregs are transforming growth factor-? dependent and express latency-associated peptide (LAP) on their surface and were discovered in the context of oral tolerance. Tr1 type Tregs (interleukin-10 dependent) are induced by nasal antigen and forkhead box protein 3+ iTregs are induced by oral antigen and by oral administration of aryl hydrocarbon receptor ligands. Oral or nasal antigen ameliorates autoimmune and inflammatory diseases in animal models by inducing Tregs. Furthermore, anti-CD3 monoclonal antibody is active at mucosal surfaces and oral or nasal anti-CD3 monoclonal antibody induces LAP+ Tregs that suppresses animal models (experimental autoimmune encephalitis, type 1 and type 2 diabetes, lupus, arthritis, atherosclerosis) and is being tested in humans. Although there is a large literature on treatment of animal models by mucosal tolerance and some positive results in humans, this approach has yet to be translated to the clinic. The successful translation will require defining responsive patient populations, validating biomarkers to measure immunologic effects, and using combination therapy and immune adjuvants to enhance Treg induction. A major avenue being investigated for the treatment of autoimmunity is the induction of Tregs and mucosal tolerance represents a non-toxic, physiologic approach to reach this goal.

Weiner, Howard L.; da Cunha, Andre Pires; Quintana, Francisco; Wu, Henry

2012-01-01

280

Oral Tolerance  

PubMed Central

Summary The gut-associated lymphoid tissue (GALT) is the largest immune organ in the body and is the primary route by which we are exposed to antigens. Tolerance induction is the default immune pathway in the gut, and the type of tolerance induced relates to the dose of antigen fed: anergy/deletion (high dose) or regulatory T-cell (Treg) induction (low dose). Conditioning of gut dendritic cells by gut epithelial cells and the gut flora, which itself has a major influence on gut immunity, induces a CD103+ retinoic acid-dependent dendritic cell that induces Tregs. A number of Tregs are induced at mucosal surfaces. Th3 type Tregs are transforming growth factor-? (TGF-?) dependent and express latency-associated peptide (LAP) on their surface and were discovered in the context of oral tolerance. Tr1 type Tregs (interleukin-10 dependent) are induced by nasal antigen and Foxp3 iTregs are induced by oral antigen and by oral administration of aryl hydrocarbon receptor ligands. Oral or nasal antigen ameliorates autoimmune and inflammatory diseases in animal models by inducing Tregs. Furthermore, anti-CD3 monoclonal antibody is active at mucosal surfaces and oral or nasal anti-CD3 monoclonal antibody induces a LAP+ Tregs that suppresses animal models (experimental autoimmune encephalitis, type 1 and type 2 diabetes, lupus, arthritis, atherosclerosis) and is being tested in humans. Although there is a large literature on treatment of animal models by mucosal tolerance and some positive results in humans, this approach has yet to be translated to the clinic. The successful translation will require defining responsive patient populations, validating biomarkers to measure immunologic effects, and using combination therapy and immune adjuvants to enhance Treg induction. A major avenue being investigated for the treatment of autoimmunity is the induction of Tregs and mucosal tolerance represents a non-toxic, physiologic approach to reach this goal.

Weiner, Howard L.; Cunha, Andre Pires da; Quintana, Francisco; Wu, Henry

2011-01-01

281

Altered signalling thresholds in T lymphocytes cause autoimmune arthritis  

Microsoft Academic Search

The development of spontaneous autoimmunity in inbred strains of rodents has allowed us to investigate the molecular basis of chronic inflammatory disease in ways that would not be possible in humans. Recently, two new mouse models of autoimmune inflammatory polyarthritis have been reported that demonstrate how alterations in signalling thresholds sufficient to perturb central T-cell tolerance lead to inflammatory arthritis.

Andrew P Cope

2004-01-01

282

Method for quantitative estimation of thermal thresholds in patients  

Microsoft Academic Search

A quantitative method for the examination of thermal sensibility was applied in 26 normal subjects and in patients with various neurological disorders. The stimulation technique resembled Békésy audiometry: the patient reversed the direction of the temperature change of a thermode whenever warm, cold, or thermal pain thresholds were reached. The resulting temperature curve enables a quantitative description of the subject's

H Fruhstorfer; U Lindblom; W C Schmidt

1976-01-01

283

Setting Graduation Rate Thresholds.  

ERIC Educational Resources Information Center

Reviews the college completion/graduation rate thresholds developed by several states and discusses advantages and disadvantages of several statistical approaches, including use of the one standard deviation lower bound method, the logit prediction bound method, the linear regression method, and the logistic regression method. (DB)

Underwood, David G.; Rieck, James R.

1999-01-01

284

Canonically optimum threshold detection  

Microsoft Academic Search

A general canonical theory is developed for the systematic approximation of optimum, or Bayes, detection procedures in the critical limiting threshold mode of operation. The approximations to Bayes detectors introduced here are called locally optimum Bayes detectors (LOBD's) and are defined by the condition that they produce the same value of average risk and its derivative for vanishingly small input

D. Middleton

1966-01-01

285

Robust Threshold DSS Signatures  

Microsoft Academic Search

We present threshold DSS (Digital Signature Standard) signatures where the power to sign is shared by players such that for a given parameter any subset of signers can collaborate to produce a valid DSS signature on any given message, but no subset of corrupted players can forge a signature (in particular, cannot learn the signature key). In addition, we present

Rosario Gennaro; Stanislaw Jarecki; Hugo Krawczyk; Tal Rabin

1996-01-01

286

Practical Threshold Signatures  

Microsoft Academic Search

We present an RSA threshold signature scheme. The scheme enjoys the following properties: 1. it is unforgeable and robust in the random oracle model, assuming the RSA problem is hard; 2. signature share generation and veriflcation is completely non-inter- active; 3. the size of an individual signature share is bounded by a constant times the size of the RSA modulus.

Victor Shoup

2000-01-01

287

Fault-tolerant almost exact state transmission.  

PubMed

We show that a category of one-dimensional XY-type models may enable high-fidelity quantum state transmissions, regardless of details of coupling configurations. This observation leads to a fault-tolerant design of a state transmission setup. The setup is fault-tolerant, with specified thresholds, against engineering failures of coupling configurations, fabrication imperfections or defects, and even time-dependent noises. We propose an experimental implementation of the fault-tolerant scheme using hard-core bosons in one-dimensional optical lattices. PMID:24185259

Wang, Zhao-Ming; Wu, Lian-Ao; Modugno, Michele; Yao, Wang; Shao, Bin

2013-11-04

288

Reflex receptive fields are enlarged in patients with musculoskeletal low back and neck pain.  

PubMed

Pain hypersensitivity has been consistently detected in chronic pain conditions, but the underlying mechanisms are difficult to investigate in humans and thus poorly understood. Patients with endometriosis pain display enlarged reflex receptive fields (RRF), providing a new perspective in the identification of possible mechanisms behind hypersensitivity states in humans. The primary hypothesis of this study was that RRF are enlarged in patients with musculoskeletal pain. Secondary study end points were subjective pain thresholds and nociceptive withdrawal reflex (NWR) thresholds after single and repeated (temporal summation) electrical stimulation. Forty chronic neck pain patients, 40 chronic low back pain patients, and 24 acute low back pain patients were tested. Electrical stimuli were applied to 10 sites on the sole of the foot to quantify the RRF, defined as the area of the foot from where a reflex was evoked. For the secondary end points, electrical stimuli were applied to the cutaneous innervation area of the sural nerve. All patient groups presented enlarged RRF areas compared to pain-free volunteers (P<.001). Moreover, they also displayed lower NWR and pain thresholds to single and repeated electrical stimulation (P<.001). These results demonstrate that musculoskeletal pain conditions are characterized by enlarged RRF, lowered NWR and pain thresholds, and facilitated temporal summation, most likely caused by widespread spinal hyperexcitability. This study contributes to a better understanding of the mechanisms underlying these pain conditions, and it supports the use of the RRF and NWR as objective biomarkers for pain hypersensitivity in clinical and experimental pain research. PMID:23707309

Biurrun Manresa, José A; Neziri, Alban Y; Curatolo, Michele; Arendt-Nielsen, Lars; Andersen, Ole K

2013-04-09

289

Sustained antinociceptive effect of cannabinoid receptor agonist WIN 55,212-2 over time in rat model of neuropathic spinal cord injury pain  

PubMed Central

A significant complaint associated with spinal cord injury (SCI) is chronic pain, which includes symptoms such as cutaneous hypersensitivity and spontaneous unevoked pain and is difficult to treat with currently available drugs. One complication with current analgesics is tolerance, a decrease in efficacy with repeated treatment over time. One promising class of pharmacological treatment is cannabinoid (CB) receptor agonists. The current study assessed the efficacy of the CB receptor agonist WIN 55,212-2 (WIN) in a rat model of neuropathic SCI pain. Brief spinal compression leads to significant hindpaw hypersensitivity to tactile stimulation. WIN dose-dependently increased withdrawal thresholds and continued to demonstrate efficacy over a twice-daily 7-day treatment regimen. By contrast, the efficacy of morphine in SCI rats decreased over the same treatment period. Similarly, the antinociceptive efficacy of WIN to acute noxious heat in uninjured rats diminished over time. These data suggest that the sustained efficacy of a CB receptor agonist for pain could depend on the pain state. Such agonists may hold promise for long-term use in alleviating chronic SCI pain.

Hama, Aldric; Sagen, Jacqueline

2009-01-01

290

Gelsemine, a principal alkaloid from Gelsemium sempervirens Ait., exhibits potent and specific antinociception in chronic pain by acting at spinal ?3 glycine receptors.  

PubMed

The present study examined the antinociceptive effects of gelsemine, the principal alkaloid in Gelsemium sempervirens Ait. A single intrathecal injection of gelsemine produced potent and specific antinociception in formalin-induced tonic pain, bone cancer-induced mechanical allodynia, and spinal nerve ligation-induced painful neuropathy. The antinociception was dose-dependent, with maximal inhibition of 50% to 60% and ED50 values of 0.5 to 0.6?g. Multiple daily intrathecal injections of gelsemine for 7days induced no tolerance to antinociception in the rat model of bone cancer pain. Spinal gelsemine was not effective in altering contralateral paw withdrawal thresholds, and had only a slight inhibitory effect on formalin-induced acute nociception. The specific antinociception of gelsemine in chronic pain was blocked dose-dependently by the glycine receptor (GlyR) antagonist strychnine with an apparent ID50 value of 3.8?g. Gelsemine concentration-dependently displaced H(3)-strychnine binding to the membrane fraction of rat spinal cord homogenates, with a 100% displacement and a Ki of 21.9?M. Gene ablation of the GlyR ?3 subunit (?3 GlyR) but not ?1 GlyR, by a 7-day intrathecal injection of small interfering RNA (siRNA) targeting ?3 GlyR or ?1 GlyR, nearly completely prevented gelsemine-induced antinociception in neuropathic pain. Our results demonstrate that gelsemine produces potent and specific antinociception in chronic pain states without induction of apparent tolerance. The results also suggest that gelsemine produces antinociception by activation of spinal ?3 glycine receptors, and support the notion that spinal ?3 glycine receptors are a potential therapeutic target molecule for the management of chronic pain. PMID:23886522

Zhang, Jing-Yang; Gong, Nian; Huang, Jin-Lu; Guo, Ling-Chen; Wang, Yong-Xiang

2013-07-22

291

Urination - painful  

MedlinePLUS

... such as yeast or other infections of the vulva and vagina Other causes of painful urination include: ... in the urine ? Are there any rashes or itching in the genital area? What medications are you ...

292

Ankle Pain  

MedlinePLUS

... or outside of your ankle or along the Achilles tendon, which connects the muscles in your lower leg ... Common causes of ankle pain include: Achilles tendinitis Achilles tendon rupture Avulsion fracture Bone spurs Broken ankle/broken ...

293

Phantom Pain  

MedlinePLUS

... often results in painful nerve activity. Poor-fitting artificial limb (prosthesis). Talk to your doctor to be sure you're putting your artificial limb on correctly and that it fits properly. If ...

294

Back Pain  

MedlinePLUS

... with your spinal cord, muscles, nerves or disks. Magnetic resonance imaging (MRI) or computerized tomography (CT) scans. ... Devereaux M. Low back pain. Medical Clinics of North America. 2009;93:477. Hoy D, et al. ...

295

Reliability of the conditioned pain modulation paradigm to assess endogenous inhibitory pain pathways  

PubMed Central

BACKGROUND: Conditioned pain modulation paradigms are often used to assess the diffuse noxious inhibitory control (DNIC) system. DNICs provide one of the main supraspinal pain inhibitory pathways and are impaired in several chronic pain populations. Only one previous study has examined the psychometric properties of the conditioned pain modulation technique and this study did not evaluate intersession reliability. OBJECTIVES: To evaluate and compare the intra- and intersession reliability of two conditioned pain modulation paradigms using different conditioning stimuli, and to determine the time course of conditioned pain inhibition following stimulus removal. METHODS: An electronic pressure transducer was used to determine the pressure-pain threshold at the knee during painful conditioning of the opposite hand using the ischemic arm test and the cold pressor test. Assessments were completed twice on one day and repeated once approximately three days later. RESULTS: The two conditioning stimuli resulted in a similar increase in the pressure-pain threshold at the knee, reflecting presumed activation of the DNIC system. Intrasession intraclass correlation coefficients for the cold pressor (0.85) and ischemic arm tests (0.75) were excellent. The intersession intraclass correlation coefficient for the cold pressor test was good (0.66) but was poor for the ischemic arm test (?0.4). Inhibition of the pressure-pain threshold remained significant at 10 min following conditioning, but returned to baseline by 15 min. CONCLUSIONS: Within-session reliability of DNIC assessment using conditioned pain modulation paradigms was excellent, but the applicability of assessing pain modulation over multiple sessions was influenced by the conditioning stimulus. The cold pressor test was the superior technique.

Lewis, Gwyn N; Luke, Heales; Rice, David A; Rome, Keith; McNair, Peter J

2012-01-01

296

What Is Chronic Pain?  

MedlinePLUS Videos and Cool Tools

... Learned Going to the ER Communication Tools Pain Management Programs Videos Resources Glossary FAQs Surveys September is ... for Understanding Pain Pain Awareness Toolkits Home Pain Management Tools Videos What Is Chronic Pain? Featured Tool ...

297

[Wrist pain].  

PubMed

Acute or chronic wrist pain is a relatively frequent complaint that may involve all age groups. The pain may be of osseous, articular, periarticular, neurologic, vascular origin, or be referred from the cervical spine, shoulder or elbow. The diagnosis should be oriented by a precise history and clinical examination. More specialised exams will be required according to clinical findings. Psychosocial and environmental influences need to be taken into consideration. PMID:17233497

Sadowski, M; Della Santa, D

2006-12-20

298

Quantitative sensory testing: effect of site and skin temperature on thermal thresholds  

Microsoft Academic Search

Objective: To determine the effect of different sites and local skin temperature on thermal thresholds.Methods: Cool and warm detection and cold and heat pain thresholds were compared in 46 normal volunteers at the thenar eminence (TE), dorsum of the hand (DH), volar surface of the wrist (VW) and dorsum of the foot (DF).Results: The hand is more sensitive than the

Louise G Hagander; Hani A Midani; Michael A Kuskowski; Gareth J. G Parry

2000-01-01

299

Children's selective attention to pain and avoidance behaviour: The role of child and parental catastrophizing about pain.  

PubMed

The present study investigated selective attention to pain in children, its implications for child avoidance behaviour, and the moderating role of dimensions comprising child and parental catastrophizing about pain (ie, rumination, magnification, and helplessness). Participants were 59 children (31 boys) aged 10-16 years and one of their parents (41 mothers). Children performed a dot-probe task in which child facial pain displays of varying pain expressiveness were presented. Child avoidance behaviour was indexed by child pain tolerance during a cold-pressor task. Children and parents completed measures of child and parent pain catastrophizing, respectively. Findings indicated that both the nature of child selective attention to pain and the impact of selective attention upon child avoidance behaviour were differentially sensitive to specific dimensions of child and parental catastrophizing. Specifically, findings showed greater tendency to shift attention away from pain faces (ie, attentional avoidance) among children reporting greater pain magnification. A similar pattern was observed in terms of parental characteristics, such that children increasingly shifted attention away from pain with increasing levels of parental rumination and helplessness. Furthermore, child attentional avoidance was associated with greater avoidance behaviour (ie, lower pain tolerance) among children reporting high levels of pain magnification and those whose parents reported greater rumination about pain. The current findings corroborate catastrophizing as a multidimensional construct that may differentially impact outcomes and attest to the importance of assessing both child and parental characteristics in relation to child pain-related attention and avoidance behaviour. Further research directions are discussed. PMID:23792243

Vervoort, Tine; Trost, Zina; Van Ryckeghem, Dimitri M L

2013-06-18

300

The reactor noise threshold  

Microsoft Academic Search

Time-domain noise analysis techniques such as the Rossi-[alpha], the variance-to-mean, and the interval-distribution methods can be used to measure fundamental reactor parameters in a wise variety of reactor systems, provided the power level of the system is not too high. Simple expressions have been derived that define the maximum power level (i.e., the reactor noise threshold) above which time-domain reactor

Spriggs

1994-01-01

301

Some photoneutron thresholds  

Microsoft Academic Search

The photeneutron thresholds for a number of elements which have 100% ; abundance (or nearly so) in one stable isotope have been measured. The following ; values in Mev were found: Na (12.47 plus or minus 0.05), Al (12.98 plus or ; minus 0.08), P (12.50 plus or minus 0.05), V (11.16 plus or minus 0.05), Mn ; (10.14 plus

B. G. Chidley; L. Katz; S. L. f Kowalski

1958-01-01

302

Threshold Entrusted Undeniable Signature  

Microsoft Academic Search

\\u000a Entrusted undeniable signatures are like undeniable signatures, except that the disavowal protocol can only be run by a court\\u000a in order to resolve a formal dispute. This paper introduces threshold entrusted undeniable signature scheme without trusted\\u000a center. It is shown how the power to run a disavowal protocol of entrusted undeniable signature can be distributed to n agents such that

Seungjoo Kim; Dongho Won

2004-01-01

303

Vision thresholds revisited  

NASA Astrophysics Data System (ADS)

During and just after World War II there was intense interest in the threshold for seeing faint sources against illuminated backgrounds. Knoll, Tousey and Hulburt (1946, 1948) determined the threshold for (effectively) point sources seen against backgrounds ranging in brightness from darkness to subdued daylight. Blackwell (1946) gave contrast ratios for sources of various sizes ranging from point sources up to circular disks of 6 degrees diameter, all seen against the same range of brightnesses, and determined by a very large number of visual observations made by a team of observers. I have combined the two sets of results, and represented them by an improvement on the theoretical formula for threshold illuminance as a function of background brightness which was suggested by Hecht (1934). My formula agrees very well with the observations, and is very suitable for incorporation into computer programs. Applications have been made to problems where the background brightness is caused by light pollution, and the source size is determined by the seeing. These include the optimum magnification and limiting magnitude of telescopes, and the analysis of visual limiting magnitudes determined by Bowen (1947) to determine the night sky brightness at Mount Wilson in 1947.

Garstang, R. H.

1999-05-01

304

Threshold Concepts in Research Education and Evidence of Threshold Crossing  

ERIC Educational Resources Information Center

Most work on threshold concepts has hitherto related to discipline-specific undergraduate education, however, the idea of generic doctoral-level threshold concepts appeared to us to provide a strong and useful framework to support research learning and teaching at the graduate level. The early work regarding research-level threshold concepts is…

Kiley, Margaret; Wisker, Gina

2009-01-01

305

Sensory threshold measurements for electrical stimulation of the digits.  

PubMed

Repeated impedance measurements of electrical stimulation to the finger using the stimulator of an electromyograph were evaluated in seven normal subjects to determine whether reliable threshold values to perception of pain could be obtained. Stimuli were delivered through ring or disc electrodes separated by 3 cm and interfaced to the skin of the digit with EKG paste. Stimulation through these electrodes produced only relative values of threshold, expressed as a potentiometer dial setting. Such values proved to be meaningful only when repeated during a single session. A possible reason for the apparent unreliability of repeated measurements over time is discussed. When a constant current source was substituted, reliable and consistent threshold measurements were obtained. It is suggested that the clinician wishing to make accurate, repeatable and quantified measurements of patient thresholds to electrical stimulation of the finger employ a nonloading source, namely, a constant current or constant voltage stimulator. PMID:843204

Wolf, S L; Cohen, B A

1977-03-01

306

Heart rate variability and pain: associations of two interrelated homeostatic processes.  

PubMed

Between-person variability in pain sensitivity remains poorly understood. Given a conceptualization of pain as a homeostatic emotion, we hypothesized inverse associations between measures of resting heart rate variability (HRV), an index of autonomic regulation of heart rate that has been linked to emotionality, and sensitivity to subsequently administered thermal pain. Resting electrocardiography was collected, and frequency-domain measures of HRV were derived through spectral analysis. Fifty-nine right-handed participants provided ratings of pain intensity and unpleasantness following exposure to 4 degrees C thermal pain stimulation, and indicated their thresholds for barely noticeable and moderate pain during three exposures to decreasing temperature. Greater low-frequency HRV was associated with lower ratings of 4 degrees C pain unpleasantness and higher thresholds for barely noticeable and moderate pain. High-frequency HRV was unrelated to measures of pain sensitivity. Findings suggest pain sensitivity is influenced by characteristics of a central homeostatic system also involved in emotion. PMID:18023960

Appelhans, Bradley M; Luecken, Linda J

2007-10-12

307

Sample Splitting and Threshold Estimation  

Microsoft Academic Search

Threshold models have a wide variety of applications in economics. Direct applications include models of separating and multiple equilibria. Other applications include empirical sample splitting when the sample split is based on a continuously-distributed variable such as firm size. In addition, threshold models may be used as a parsimonious strategy for nonparametric function estimation. For example, the threshold autoregressive model

Bruce E. Hansen

2000-01-01

308

Spatial Variable Thresholding for SCALES  

Microsoft Academic Search

The Stochastic Coherent Adaptive Large Eddy Simulation (SCALES) is a novel wavelet-based approach that resolves energy containing turbulent motions using wavelet multiresolution decomposition and self-adaptivity. The extraction of the most energetic structures is achieved using wavelet thresholding filter with a priori prescribed threshold level. This strategy, although successful, has a major drawback: the thresholding criterion is global and does not

Alireza Nejadmalayeri; Oleg V. Vasilyev; Alexei Vezolainen; Giuliano de Stefano

2009-01-01

309

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

PubMed Central

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 ?-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-1? and tumor necrosis factor-? (TNF-?) were associated with an enhanced sensitivity to the opioid analgesic effect (IL-1?, P?=?0.0218; TNF-?, 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 increased potency to opioid analgesia; other pro-inflammatory mediators also predicted an enhanced opioid potency. Trial Registration: ClinicalTrials.gov NCT00672737.

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

2013-01-01

310

Central pain: clinical and physiological characteristics.  

PubMed Central

OBJECTIVES--To study the clinical and pathophysiological features of central pain due to damage to the CNS. METHODS--156 patients (mostly with ischaemic strokes, some with infarct after subarachnoid haemorrhage and other cerebral conditions; one with bulbar and others with spinal pathology) with central pain have been investigated clinically and varying numbers instrumentally with respect to quantitative somatosensory perception thresholds and autonomic function. RESULTS--Pain onset was immediate in a minority; and from a week or two up to six years in > 60%. For those with supraspinal ischaemic lesions, the median age of onset was 59; dominant and non-dominant sides were equally affected. Two thirds of the patients had allodynia, including a previously undescribed movement allodynia apparently triggered from group I afferents. Most patients exhibited autonomic instability in that their pain was increased by physical and emotional stress and alleviated by relaxation; cutaneous blood flow and sweating may also be affected. Pain occurred within a larger area of differential sensory deficit. The critical deficit seems to be for thermal and pinprick sensations, which were more pronounced in areas of greatest than in areas of least pain; whereas low threshold mechanoceptive functions, if affected, did not vary between areas of greatest and least pain. Skinfold pinch (tissue damage) pain thresholds were only slightly affected in supraspinal cases, but greatly increased in patients with spinal lesions; thermal (heat) pain did not show this dissociation. CONCLUSION--The pathogenetic hypothesis which seems best to fit the findings is that there is up regulation or down regulation of receptors for transmitters, possibly mainly noradrenergic, over time.

Bowsher, D

1996-01-01

311

The reactor noise threshold  

SciTech Connect

Time-domain noise analysis techniques such as the Rossi-[alpha], the variance-to-mean, and the interval-distribution methods can be used to measure fundamental reactor parameters in a wise variety of reactor systems, provided the power level of the system is not too high. Simple expressions have been derived that define the maximum power level (i.e., the reactor noise threshold) above which time-domain reactor noise techniques are likely to fail in subcritical, critical, and supercritical systems.

Spriggs, G.D. (Los Alamos National Lab., NM (United States))

1994-01-01

312

Witnessing hateful people in pain modulates brain activity in regions associated with physical pain and reward.  

PubMed

How does witnessing a hateful person in pain compare to witnessing a likable person in pain? The current study compared the brain bases for how we perceive likable people in pain with those of viewing hateful people in pain. While social bonds are built through sharing the plight and pain of others in the name of empathy, viewing a hateful person in pain also has many potential ramifications. In this functional Magnetic Resonance Imaging (fMRI) study, Caucasian Jewish male participants viewed videos of (1) disliked, hateful, anti-Semitic individuals, and (2) liked, non-hateful, tolerant individuals in pain. The results showed that, compared with viewing liked people, viewing hateful people in pain elicited increased responses in regions associated with observation of physical pain (the insular cortex, the anterior cingulate cortex (ACC), and the somatosensory cortex), reward processing (the striatum), and frontal regions associated with emotion regulation. Functional connectivity analyses revealed connections between seed regions in the left ACC and right insular cortex with reward regions, the amygdala, and frontal regions associated with emotion regulation. These data indicate that regions of the brain active while viewing someone in pain may be more active in response to the danger or threat posed by witnessing the pain of a hateful individual more so than the desire to empathize with a likable person's pain. PMID:24167496

Fox, Glenn R; Sobhani, Mona; Aziz-Zadeh, Lisa

2013-10-23

313

Witnessing hateful people in pain modulates brain activity in regions associated with physical pain and reward  

PubMed Central

How does witnessing a hateful person in pain compare to witnessing a likable person in pain? The current study compared the brain bases for how we perceive likable people in pain with those of viewing hateful people in pain. While social bonds are built through sharing the plight and pain of others in the name of empathy, viewing a hateful person in pain also has many potential ramifications. In this functional Magnetic Resonance Imaging (fMRI) study, Caucasian Jewish male participants viewed videos of (1) disliked, hateful, anti-Semitic individuals, and (2) liked, non-hateful, tolerant individuals in pain. The results showed that, compared with viewing liked people, viewing hateful people in pain elicited increased responses in regions associated with observation of physical pain (the insular cortex, the anterior cingulate cortex (ACC), and the somatosensory cortex), reward processing (the striatum), and frontal regions associated with emotion regulation. Functional connectivity analyses revealed connections between seed regions in the left ACC and right insular cortex with reward regions, the amygdala, and frontal regions associated with emotion regulation. These data indicate that regions of the brain active while viewing someone in pain may be more active in response to the danger or threat posed by witnessing the pain of a hateful individual more so than the desire to empathize with a likable person's pain.

Fox, Glenn R.; Sobhani, Mona; Aziz-Zadeh, Lisa

2013-01-01

314

Antisense oligonucleotide knockdown of mGlu? receptor attenuates the antinociceptive tolerance and up-regulated expression of spinal protein kinase C associated with chronic morphine treatment.  

PubMed

Spinal metabotropic glutamate receptor 5 (mGlu? receptor) is known to influence the development of intrathecal morphine antinociceptive tolerance. However, the signaling mechanisms remain unknown. We carried out intrathecal administration of an antisense oligodeoxynucleotide (ODN), which results in reduced expression of spinal mGlu? receptor, to determine its effects on morphine tolerance and spinal protein kinase C (PKC) expression. Rats were treated intrathecally with saline, morphine, mGlu5 receptor antisense ODN or mGlu5 receptor mismatched ODN. Behavioral tests were used to test the thermal and mechanical pain thresholds. Eight days later, rats were sacrificed and spinal cords were harvested to assess the expression of spinal PKC (?, ? and ?) by Western blotting and real-time polymerase chain reaction (PCR). Compared to control, intrathecal mGlu? receptor antisense ODN resulted in a ~53.9% reduction of spinal mGlu? receptor after 8days treatment. The mGlu5 receptor antisense ODN prevented the development of morphine tolerance. Expression of spinal PKC (?, ? and ?) was up-regulated at the mRNA and protein levels during the development of tolerance. Meanwhile, antisense ODN but not mismatched ODN reduced the spinal dorsal horn levels of PKC (?, ? and ?) which had been up-regulated after morphine exposure. We conclude that mGlu? receptor participates in the development of morphine tolerance. Expression of spinal PKC (?, ? and ?) at the mRNA and protein levels increased during morphine tolerance. Antisense ODN of mGlu? receptor prevented the tolerance and inhibited the altered expression of spinal PKC (?, ? and ?) during the development of tolerance. PMID:22429573

Xu, Tao; Chen, Moxi; Zhou, Quanhong; Xue, Ying; Wang, Li; Bil De Arce, Vida J; Zhang, Xiaoli; Jiang, Wei

2012-03-12

315

Back pain during growth.  

PubMed

It is wrong to believe that back pain only burdens adults: the yearly incidence during growth ranges from 10-20%, continuously increasing from childhood to adolescence. Rapid growth-related muscular dysbalance and insufficiency, poor physical condition in an increasingly sedentary adolescent community or - vice versa - high level sports activities, account for the most prevalent functional pain syndromes. In contrast to adults the correlation of radiographic findings with pain is high: the younger the patient, the higher the probability to establish a rare morphologic cause such as benign or malignant tumours, congenital malformations and infections. In children younger than 5 years old, the likelihood is more than 50%. The following red flags should lower the threshold for a quick in-depth analysis of the problem: Age of the patient <5 years, acute trauma, functional limitation for daily activities, irradiating pain, loss of weight, duration >4 weeks, history of tumour, exposition to tuberculosis, night pain and fever. High level sport equals a biomechanical field test which reveals the biologic individual response of the growing spine to the sports-related forces. Symptomatic or asymptomatic inhibitory or stimulatory growth disturbances like Scheuermann disease, scoliosis or fatigue fractures represent the most frequent pathomorphologies. They usually occur at the disk-growth plate compound: intraspongious disk herniation, diminuition of anterior growth with vertebral wedging and apophyseal ring fractures often occur when the biomechanical impacts exceed the mechanical resistance of the cartilaginous endplates. Spondylolysis is a benign condition which rarely becomes symptomatic and responds well to conservative measures. Associated slippage of L5 on S1 is frequent but rarely progresses. The pubertal spinal growth spurt is the main risk factor for further slippage, whereas sports activity - even at a high level - is not. Therefore, the athlete should only be precluded from training if pain persists or in case of high grade slips. Perturbance of the sagittal profile with increase of lumbar lordosis, flattening of the thoracic spine and retroflexion of the pelvis with hamstrings contractures are strong signs for a grade IV olisthesis or spondyloptosis with subsequent lumbosacral kyphosis. Idiopathic scoliosis is not related to pain unless it is a marked (thoraco-) lumbar curve or if there is an underlying spinal cord pathology. Chronic back pain is an under recognised entity characterised by its duration (>3 months or recurrence within 3 months) and its social impacts such as isolation and absence from school or work. It represents an independent disease, uncoupled from any initial trigger. Multimodal therapeutic strategies are more successful than isolated, somatising orthopaedic treatment. Primary and secondary preventive active measures for the physically passive adolescents, regular sports medical check-up's for the young high level athletes, the awareness for the rare but potentially disastrous pathologies and the recognition of chronic pain syndromes are the cornerstones for successful treatment of back pain during growth. PMID:23299906

Hasler, Carol C

2013-01-08

316

A randomized, placebo-controlled double-blinded comparative clinical study of five over-the-counter non-pharmacological topical analgesics for myofascial pain: single session findings  

PubMed Central

Objectives To investigate the effects of topical agents for the treatment of Myofascial Pain Syndrome (MPS) and Myofascial Trigger Point (MTRP). Methods Subjects with an identifiable trigger point in the trapezius muscle, age 18-80 were recruited for a single-session randomized, placebo-blinded clinical study. Baseline measurements of trapezius muscle pressure pain threshold (PPT: by pressure algometer) along with right and left cervical lateral flexion (rangiometer) were obtained by a blinded examiner. An assessor blinded to the outcomes assessments applied one of 6 topical formulations which had been placed in identical plastic containers. Five of these topicals were proposed active formulations; the control group was given a non-active formulation (PLA). Five minutes after the application of the formula the outcome measures were re-tested. Data were analyzed with a 5-way ANOVA and Holms-adjusted t-tests with an alpha level of 0.05. Results 120 subjects were entered into the study (63 females; ages 16-82); 20 subjects randomly allocated into each group. The pre- and post-treatment results for pressure threshold did show significant intra-group increases for the Ben-Gay Ultra Strength Muscle Pain Ointment (BG), the Professional Therapy MuscleCare Roll-on (PTMC roll-on) and Motion Medicine Cream (MM) with an increased threshold of 0.5 kg/cm2 (+/-0.15), 0.72 kg/cm2 (+/-0.17) and 0.47 Kg/cm2 (+/-0.19) respectively. With respect to the inter-group comparisons, PTMC roll-on showed significant increases in pressure threshold compared with Placebo (PLA) (p = 0.002) and Icy Hot Extra Strength Cream (IH) (p = 0.006). In addition, BG demonstrated significant increases in pressure threshold compared with PLA (p = 0.0003). Conclusions With regards to pressure threshold, PTMC roll-on, BG and MM showed significant increases in pain threshold tolerance after a short-term application on a trigger points located in the trapezius muscle. PTMC roll-on and BG were both shown to be superior vs placebo while PTMC was also shown to be superior to IH in patients with trigger points located in the trapezius muscle on a single application. CMCC Research Ethics Board Approval # 1012X01, 2011

2012-01-01

317

Coloring geographical threshold graphs  

SciTech Connect

We propose a coloring algorithm for sparse random graphs generated by the geographical threshold graph (GTG) model, a generalization of random geometric graphs (RGG). In a GTG, nodes are distributed in a Euclidean space, and edges are assigned according to a threshold function involving the distance between nodes as well as randomly chosen node weights. The motivation for analyzing this model is that many real networks (e.g., wireless networks, the Internet, etc.) need to be studied by using a 'richer' stochastic model (which in this case includes both a distance between nodes and weights on the nodes). Here, we analyze the GTG coloring algorithm together with the graph's clique number, showing formally that in spite of the differences in structure between GTG and RGG, the asymptotic behavior of the chromatic number is identical: {chi}1n 1n n / 1n n (1 + {omicron}(1)). Finally, we consider the leading corrections to this expression, again using the coloring algorithm and clique number to provide bounds on the chromatic number. We show that the gap between the lower and upper bound is within C 1n n / (1n 1n n){sup 2}, and specify the constant C.

Bradonjic, Milan [Los Alamos National Laboratory; Percus, Allon [Los Alamos National Laboratory; Muller, Tobias [EINDHOVEN UNIV. OF TECH

2008-01-01

318

Differential Analgesic Sensitivity of Two Distinct Neuropathic Pain Models  

Microsoft Academic Search

Progressive tactile hypersensitivity (PTH) manifesting after sciatic nerve crush and spared nerve injury (SNI) are two distinct rodent experimental models of neuro- pathic pain. PTH develops months after recovery from the nerve crush in response to repeated intermittent low-threshold mechanical stimulation of the reinner- vated sciatic nerve skin territory and represents a model of stimulus-induced pain. SNI is characterized by

Isabelle Decosterd; Andrew Allchorne; Clifford J. Woolf

2004-01-01

319

No Pain Relief with the Rubber Hand Illusion  

PubMed Central

The sense of body ownership can be easily disrupted during illusions and the most common illusion is the rubber hand illusion. An idea that is rapidly gaining popularity in clinical pain medicine is that body ownership illusions can be used to modify pathological pain sensations and induce analgesia. However, this idea has not been empirically evaluated. Two separate research laboratories undertook independent randomized repeated measures experiments, both designed to detect an effect of the rubber hand illusion on experimentally induced hand pain. In Experiment 1, 16 healthy volunteers rated the pain evoked by noxious heat stimuli (5 s duration; interstimulus interval 25 s) of set temperatures (47°, 48° and 49°C) during the rubber hand illusion or during a control condition. There was a main effect of stimulus temperature on pain ratings, but no main effect of condition (p?=?0.32), nor a condition x temperature interaction (p?=?0.31). In Experiment 2, 20 healthy volunteers underwent quantitative sensory testing to determine heat and cold pain thresholds during the rubber hand illusion or during a control condition. Secondary analyses involved heat and cold detection thresholds and paradoxical heat sensations. Again, there was no main effect of condition on heat pain threshold (p?=?0.17), nor on cold pain threshold (p?=?0.65), nor on any of the secondary measures (p<0.56 for all). We conclude that the rubber hand illusion does not induce analgesia.

Petkova, Valeria I.; Dey, Abishikta; Barnsley, Nadia; Ingvar, Martin; McAuley, James H.; Moseley, G. Lorimer; Ehrsson, Henrik H.

2012-01-01

320

Perception of pain after resistance exercise  

PubMed Central

OBJECTIVES: The main objective was to assess the influence of resistance exercise on pain threshold and pain ratings. Secondary objectives included measuring state anxiety, body awareness, systolic blood pressure, diastolic blood pressure, and heart rate responses. METHODS: Pressure (3 kg force) was applied to the middle digit of the left hand for two minutes using a Forgione-Barber pain stimulator before and after (five minute and 15 minutes) resistance exercise and quiet rest. Resistance exercise consisted of 45 minutes of lifting three sets of 10 repetitions at 75% of an individual's one repetition maximum. Quiet rest consisted of sitting quietly in a room free from distractions. RESULTS: Data were analysed by repeated measures analysis of variance for multifactor experiments. Pain threshold was significantly higher (p<0.05) and pain ratings were significantly lower (p<0.05) five minutes after resistance exercise. Changes in pain perception were accompanied by changes in heart rate, systolic blood pressure, and body awareness after exercise. CONCLUSION: A single bout of resistance exercise is capable of modifying the sensation of experimentally induced pain. ?????

Koltyn, K. F.; Arbogast, R. W.

1998-01-01

321

[Molecular mechanism of morphine tolerance and biological approaches to resolve tolerance].  

PubMed

One of the major problems associated with the chronic use of morphine is tolerance. Repeated uses of morphine to relieve pain often cause patients to develop increasing resistance to the effects of the drugs, so that progressively higher doses are required to achieve the same analgesic effects. Acquired tolerance is thought to be different from dependence or addiction, but molecular mechanism underlying the development of tolerance is still unclear. Tolerance has been explained by desensitization of opioid receptor signaling and loss of functional receptors in the cell surface. The classical hypothesis was that phosphorylation and arrestin binding resulted in uncoupling of the receptor from G proteins, and reduced agonist efficacy. The receptor internalization would then result in fewer functional receptors at the cell surface. These events would cause so-called signaling desensitization. However, recent molecular biological studies have led researchers to revise the classical view of tolerance from observations that morphine does not always promote efficient receptor internalization. Among several key processes, the sequestration and subsequent internalization of the opioid receptor may play an important role for morphine tolerance. In fact, recent studies have suggested that receptor internalization can reduce tolerance. In addition, activation of the NMDA subtype of the glutamate receptor has been suggested as an anti-opioid system in the development of morphine tolerance. In this review, we focus on recent research progress on the morphine tolerance, and molecular biological and clinical approaches to resolve morphine tolerance. PMID:15198232

Nishikawa, Koichi; Tanobe, Kyoko; Hinohara, Hiroshi; Okamoto, Tomonori; Saito, Shigeru; Goto, Fumio

2004-05-01

322

Manipulation of pain catastrophizing: An experimental study of healthy participants  

PubMed Central

Pain catastrophizing is associated with the pain experience; however, causation has not been established. Studies which specifically manipulate catastrophizing are necessary to establish causation. The present study enrolled 100 healthy individuals. Participants were randomly assigned to repeat a positive, neutral, or one of three catastrophizing statements during a cold pressor task (CPT). Outcome measures of pain tolerance and pain intensity were recorded. No change was noted in catastrophizing immediately following the CPT (F(1,84) = 0.10, p = 0.75, partial ?2 < 0.01) independent of group assignment (F(4,84) = 0.78, p = 0.54, partial ?2 = 0.04). Pain tolerance (F(4) = 0.67, p = 0.62, partial ?2 = 0.03) and pain intensity (F(4) = 0.73, p = 0.58, partial ?2 = 0.03) did not differ by group. This study suggests catastrophizing may be difficult to manipulate through experimental pain procedures and repetition of specific catastrophizing statements was not sufficient to change levels of catastrophizing. Additionally, pain tolerance and pain intensity did not differ by group assignment. This study has implications for future studies attempting to experimentally manipulate pain catastrophizing.

Bialosky, Joel E; Hirsh, Adam T; Robinson, Michael E; George, Steven Z

2008-01-01

323

Reliability of malfunction tolerance  

Microsoft Academic Search

Generalized algorithm of fault tolerance is presented, using time, structural and information redundancy types. It is shown that algorithm of fault tolerance might be implemented using hardware and software. It is also shown that for the design of efficient fault tolerant system elements must be malfunction tolerant. The advantage of element malfunction tolerance is proven in reliability terms. Reliability analysis

Igor Schagaev

2008-01-01

324

Tolerance chart optimization  

Microsoft Academic Search

A tolerance chart is a graphical representation of a process plan and a manual procedure for controlling tolerance stackup when the machining of a component involves interdependent tolerance chains. This heuristic, experience-based method of allocating tolerances to individual cuts of a process plan can be embodied in a computer-based module. This paper introduces a graph theoretic representation for the tolerance

S. A. IRANI; R. O. MITTAL; E. A. LEHTIHET

1989-01-01

325

Achilles Pain.  

ERIC Educational Resources Information Center

|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…

Connors, G. Patrick

326

Breast pain  

PubMed Central

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.

2011-01-01

327

Factors affecting mechanical (nociceptive) thresholds in piglets  

PubMed Central

Objective To evaluate the stability and repeatability of measures of mechanical (nociceptive) thresholds in piglets and to examine potentially confounding factors when using a hand held algometer. Study design Descriptive, prospective cohort. Animals Forty-four piglets from four litters, weighing 4.6 ± 1.0 kg (mean ± SD) at 2 weeks of age. Methods Mechanical thresholds were measured twice on each of 2 days during the first and second week of life. Data were analyzed using a repeated measures design to test the effects of behavior prior to testing, sex, week, day within week, and repetition within day. The effect of body weight and the interaction between piglet weight and behaviour were also tested. Piglet was entered into the model as a random effect as an additional test of repeatability. The effect of repeated testing was used to test the stability of measures. Pearson correlations between repeated measures were used to test the repeatability of measures. Variance component analysis was used to describe the variability in the data. Results Variance component analysis indicated that piglet explained only 17% of the variance in the data. All variables in the model (behaviour prior to testing, sex, week, day within week, repetition within day, body weight, the interaction between body weight and behaviour, piglet identity) except sex had a significant effect (p < 0.04 for all). Correlations between repeated measures increased from the first to the second week. Conclusions and Clinical relevance Repeatability was acceptable only during the second week of testing and measures changed with repeated testing and increased with increasing piglet weight, indicating that time (age) and animal body weight should be taken into account when measuring mechanical (nociceptive) thresholds in piglets. Mechanical (nociceptive) thresholds can be used both for testing the efficacy of anaesthetics and analgesics, and for assessing hyperalgesia in chronic pain states in research and clinical settings.

Janczak, Andrew M; Ranheim, Birgit; Fosse, Torunn K; Hild, Sophie; Nordgreen, Janicke; Moe, Randi O; Zanella, Adroaldo J

2012-01-01

328

Factor analysis of responses to thermal, electrical, and mechanical painful stimuli supports the importance of multi-modal pain assessment.  

PubMed

During the last decade, a multi-modal approach has been established in human experimental pain research for assessing pain thresholds and responses to various experimental pain modalities. Studies have concluded that differences in responses to pain stimuli are mainly related to variation between individuals rather than variation in response to different stimulus modalities. In a factor analysis of 272 consecutive volunteers (137 men and 135 women) who underwent tests with different experimental pain modalities, it was determined whether responses to different pain modalities represent distinct individual uncorrelated dimensions of pain perception. Volunteers underwent single painful electrical stimulation, repeated painful electrical stimulation (temporal summation), test for reflex receptive field, pressure pain stimulation, heat pain stimulation, cold pain stimulation, and a cold pressor test (ice water test). Five distinct factors were found representing responses to 5 distinct experimental pain modalities: pressure, heat, cold, electrical stimulation, and reflex-receptive fields. Each of the factors explained approximately 8% to 35% of the observed variance, and the 5 factors cumulatively explained 94% of the variance. The correlation between the 5 factors was near null (median ?=0.00, range -0.03 to 0.05), with 95% confidence intervals for pairwise correlations between 2 factors excluding any relevant correlation. Results were almost similar for analyses stratified according to gender and age. Responses to different experimental pain modalities represent different specific dimensions and should be assessed in combination in future pharmacological and clinical studies to represent the complexity of nociception and pain experience. PMID:21396782

Neziri, Alban Y; Curatolo, Michele; Nüesch, Eveline; Scaramozzino, Pasquale; Andersen, Ole K; Arendt-Nielsen, Lars; Jüni, Peter

2011-03-10

329

Oscillatory threshold logic.  

PubMed

In the 1940s, the first generation of modern computers used vacuum tube oscillators as their principle components, however, with the development of the transistor, such oscillator based computers quickly became obsolete. As the demand for faster and lower power computers continues, transistors are themselves approaching their theoretical limit and emerging technologies must eventually supersede them. With the development of optical oscillators and Josephson junction technology, we are again presented with the possibility of using oscillators as the basic components of computers, and it is possible that the next generation of computers will be composed almost entirely of oscillatory devices. Here, we demonstrate how coupled threshold oscillators may be used to perform binary logic in a manner entirely consistent with modern computer architectures. We describe a variety of computational circuitry and demonstrate working oscillator models of both computation and memory. PMID:23173034

Borresen, Jon; Lynch, Stephen

2012-11-16

330

Pilot Study of Nasal Morphine-Chitosan for the Relief of Breakthrough Pain in Patients With Cancer  

Microsoft Academic Search

Breakthrough pain in patients with cancer is common, often unpredictable, and can rapidly become severe. Treatment using the oral administration of opioids is not optimal due to the slow onset of pain relief. Nasal administration of analgesics potentially offers more rapid pain relief. This study investigates the tolerability and efficacy of a novel morphine-chitosan formulation. Twenty episodes of breakthrough pain

Hilary Pavis; Andrew Wilcock; Jane Edgecombe; Diane Carr; Cathann Manderson; Ann Church; Anthony Fisher

2002-01-01

331

Central Pain Syndrome  

MedlinePLUS

NINDS Central Pain Syndrome Information Page Table of Contents (click to jump to sections) What is Central Pain Syndrome? ... is being done? Clinical Trials Organizations What is Central Pain Syndrome? Central pain syndrome is a neurological ...

332

Assessing pain in patients.  

PubMed

This article defines pain and discusses options for pain assessment. Both unidimensional and multidimensional pain assessment scales are considered and described. Nursing skills required to carry out pain assessment are identified and discussed. PMID:18376633

McLafferty, E; Farley, A

333

Pain Medications After Surgery  

MedlinePLUS

... Modern pain medications and anesthesia can control post-surgical pain and help your body heal. By Mayo ... fewer complications. The time to talk about post-surgical pain relief and pain medications is before you ...

334

Pregabalin in post traumatic neuropathic pain: Case studies  

PubMed Central

Pregabalin is effective in the treatment of peripheral and central neuropathic pain. This study evaluated the effectiveness of pregablin in management of post traumatic peripheral nerve injury facial pain not responding to other medication like analgesics. Pregabalin was well tolerated. The most common adverse effects were dizziness and tiredness.

Singh, Rakesh Kumar; Sinha, Vijay Prakash; Pal, U. S.; Yadav, Sharad C.; Singh, Maneesh K.

2012-01-01

335

Processing of pain- and body-related verbal material in chronic pain patients: central and peripheral correlates  

Microsoft Academic Search

The processing of pain-related, body-related and neutral words was assessed in chronic pain patients and matched healthy controls. During and after word presentation at perception threshold, electromyographic activity (EMG), heart rate, skin conductance level and electroencephalographic (EEG) data from 11 electrode sites were recorded. Startle responses were measured to suprathreshold word stimuli. Although the patients did not recognize more pain-related

Herta Flor; Bärbel Knost; Niels Birbaumer

1997-01-01

336

Neurobiology of Pain in Children: An Overview  

PubMed Central

The evaluation of pain in the newborn and the infant is difficult because pain is mainly a subjective phenomenon. Until a few years ago, several myths persisted. First, the myth that children, especially infants, do not feel pain the way adults do, therefore there is no untoward consequences for them. Second, lack of assessment and reassessment for the presence of pain. Third, misunderstanding of how to conceptualise and quantify a subjective experience. Fourth, lack of knowledge of pain treatment. Fifth, the notion that addressing pain in children takes too much time and effort, in ultimate analysis resulting in wasting time. Sixth, fears of hidden -and not easy to diagnose or prevent- adverse effects of analgesic medications, including respiratory depression and addiction. Finally, from a conceptual point of view, high thresholds of pain in neonates and infants were considered to be present by natural character, and useful in protecting infant from pain during birth and transit through the narrow vaginal channel. The present review is focused on the description of different theories on the pain pathogenesis in children.

Loizzo, Alberto; Loizzo, Stefano; Capasso, Anna

2009-01-01

337

Biofeedback for pain management in traumatised refugees.  

PubMed

Chronic pain (CP) and posttraumatic stress disorder (PTSD) are both frequent and often comorbid in refugees. To date, few controlled trials have studied the efficacy of treatments targeting this comorbidity; no treatment guidelines yet exist. The authors examined the feasibility and efficacy of short-term cognitive behavioural biofeedback (BF) addressing CP in traumatised refugees. The sample comprised 11 severely traumatised refugees with CP and PTSD (mean age = 36 years, SD = 6), who underwent assessment with the Mini International Neuropsychiatric Interview, Posttraumatic Diagnostic Scale, Pain Disability Index, and Visual Rating Scale. Additionally, coping with pain and psychotherapy tolerance were assessed. Acceptance of BF was high. Pre-post effects were small to medium for increased pain management and associated heart rate reactivity but large for coping with pain. The results encourage further research to confirm whether BF is indicated as a treatment component, but not a stand-alone treatment, for traumatised refugees with comorbid CP and PTSD. PMID:19675955

Muller, Julia; Karl, Anke; Denke, Claudia; Mathier, Fabienne; Dittmann, Jennifer; Rohleder, Nicolas; Knaevelsrud, Christine

2009-01-01

338

Level reduction and the quantum threshold theorem  

NASA Astrophysics Data System (ADS)

Computers have led society to the information age revolutionizing central aspects of our lives from production and communication to education and entertainment. There exist, however, important problems which are intractable with the computers available today and, experience teaches us, will remain so even with the more advanced computers we can envision for tomorrow.Quantum computers promise speedups to some of these important but classically intractable problems. Simulating physical systems, a problem of interest in a diverse range of areas from testing physical theories to understanding chemical reactions, and solving number factoring, a problem at the basis of cryptographic protocols that are used widely today on the internet, are examples of applications for which quantum computers, when built, will offer a great advantage over what is possible with classical computer technology.The construction of a quantum computer of sufficient scale to solve interesting problems is, however, especially challenging. The reason for this is that, by its very nature, operating a quantum computer will require the coherent control of the quantum state of a very large number of particles. Fortunately, the theory of quantum error correction and fault-tolerant quantum computation gives us confidence that such quantum states can be created, can be stored in memory and can also be manipulated provided the quantum computer can be isolated to a sufficient degree from sources of noise.One of the central results in the theory of fault-tolerant quantum computation, the quantum threshold theorem shows that a noisy quantum computer can accurately and efficiently simulate any ideal quantum computation provided that noise is weakly correlated and its strength is below a critical value known as the quantum accuracy threshold. This thesis provides a simpler and more transparent non-inductive proof of this theorem based on the concept of level reduction. This concept is also used in proving the quantum threshold theorem for coherent and leakage noise and for quantum computation by measurements. In addition, the proof provides a methodology which allows us to establish improved rigorous lower bounds on the value of the quantum accuracy threshold.

Aliferis, Panagiotis (Panos)

339

Doloplus-2 pain assessment: an effective tool in patients over 85 years with advanced dementia and persistent pain.  

PubMed

Persistent pain in the elderly with dementia is neglected and effective pain diagnostic tools still lack. The aim of the study was to re-assess pain after 1 year in a group of elderly with dementia, resident in a Nursing Home. Doloplus-2 scale was adopted to detect pain and to evaluate its adequacy to address analgesia. Thirty-six out of 90 residents were affected by moderate-severe dementia and 23 patients with persistent pain were enrolled in the study. The results showed a significant reduction of Doloplus-2 score in the observational period (p <0.001) and of its mean score below the pain threshold (p <0.0001). This case analysis confirmed the clinical utility of Doloplus-2 to detect pain in patients with very advanced age and with severe dementia. The tool also confirmed its handiness and clinical applicability by nurses in order to support a systematic pain assessment in long term care. PMID:23455747

Monacelli, F; Vasile Nurse, A; Odetti, P; Traverso, N

2013-01-01

340

Influence of gender and hemispheric lateralization on heat pain perception in major depression  

Microsoft Academic Search

Increased incidence of clinical pain complaints from patients with major depression, as well as increased experimental pain thresholds have been reported. The basis of this phenomenon remains unclear, as well as its relation to medication, clinical recovery, gender and lateralization of hemispheric function. We aimed to further elucidate heat pain perception in depression applying a testing battery including assessment (on

K. J. Bär; W. Greiner; A. Letsch; R. Köbele; H. Sauer

2003-01-01

341

Central sensitization and LTP: do pain and memory share similar mechanisms?  

Microsoft Academic Search

Synaptic plasticity is fundamental to many neurobiological functions, including memory and pain. Central sensitization refers to the increased synaptic efficacy established in somatosensory neurons in the dorsal horn of the spinal cord following intense peripheral noxious stimuli, tissue injury or nerve damage. This heightened synaptic transmission leads to a reduction in pain threshold, an amplification of pain responses and a

Ru-Rong Ji; Tatsuro Kohno; Kimberly A. Moore; Clifford J. Woolf

2003-01-01

342

Issues in Defining Pain  

Microsoft Academic Search

We all have experienced pain at one time or the other, but scientifically what is pain? Most of us regard pain as a negative sensation that originates in traumatized tissues and warns of injury. Ancient philosophers considered pain an emotion. Aristotle, for example, called pain a passion of the soul. Pain in humans, and probably in animals, is in part

John S. Church

343

Chronic pain and addiction: challenging co-occurring disorders.  

PubMed

Chronic pain is commonly treated by prescribing an opioid medication. For those suffering from both chronic pain and substance dependence, barriers to adequate pain management increase. This often causes both disorders to exacerbate one another. Effective treatment may also be hampered by opioid-induced hyperalgesia, tolerance, physical dependence, "chemical coping," and diminished physical and emotional functioning. This article reviews current research trends, potential problems stemming from prescription opioid use, and suggestions for clinical practice. PMID:22880539

Pohl, Mel; Smith, Logan

344

Earnings Management to Exceed Thresholds  

Microsoft Academic Search

Earnings provide important information for investment decisions. Thus, executives--who are monitored by investors, directors, customers, and suppliers--acting in self-interest and at times for shareholders, have strong incentives to manage earnings. The authors introduce behavioral thresholds for earnings management. A model shows how thresholds induce specific types of earnings management. Empirical explorations identify earnings management to exceed each of three thresholds:

Francois Degeorge; Jayendu Patel; Richard Zeckhauser

1999-01-01

345

Threshold electron excitation of Na  

SciTech Connect

Electron collisional excitation of the 4{ital D}, 5{ital D}, 4{ital P}, and 6{ital S} states of Na has been measured with about 30-meV energy resolution. Very rapid, unresolved threshold onsets are seen for all but the 4{ital P} state, and a near-threshold resonance is suggested by the 5{ital D} data. However, only weak undulations in the cross sections are observed above threshold.

Marinkovic, B.; Wang, P.; Gallagher, A. (Joint Institute for Laboratory Astrophysics, National Institute of Standards and Technology and University of Colorado, Boulder, Colorado 80309-0440 (United States))

1992-09-01

346

Shoulder pain  

PubMed Central

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.

2006-01-01

347

Shoulder pain  

PubMed Central

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, rotator cuff repair, shoulder arthroplasty, and ultrasound.

2010-01-01

348

Back pain.  

PubMed Central

1. Back pain is very common and can be the result of a wide range of different conditions. A detailed history of the complaint often points towards the cause. Positional backache suggests a mechanical cause, unremitting pain may indicate malignancy or infection especially if accompanied by night sweats, whereas morning stiffness is more often the result of inflammation. 2. Examine the patient lying and standing as outlined. A general examination should also be performed if there is a history of weight loss, night sweats, or if the patient looks ill. 3. The vast majority of cases of backache are mechanical in origin. Plain x-rays are not normally contributory and should be avoided unless there are factors in the history and examination suggestive of infection or malignancy. 4. Patients with backache and sphincter disturbance and/or perineal anaesthesia require immediate hospital admission. 5. Analgesia and bed rest are the mainstays of treatment for acute backache of mechanical origin. Once there has been some improvement, physiotherapy can be beneficial. 6. Chronic back pain is present if the complaint lasts for more than 8 weeks. Investigations should include full blood count, ESR, calcium and alkaline phosphatase. The patient needs to be referred to a rheumatologist or orthopaedic surgeon for further assessment and possible imaging studies. If no cause other than mechanical dysfunction is found the patient should be assessed by a physiotherapist and taught back care.

Beaumont, B.; Paice, E.

1992-01-01

349

Probabilistic Threshold Criterion  

SciTech Connect

The Probabilistic Shock Threshold Criterion (PSTC) Project at LLNL develops phenomenological criteria for estimating safety or performance margin on high explosive (HE) initiation in the shock initiation regime, creating tools for safety assessment and design of initiation systems and HE trains in general. Until recently, there has been little foundation for probabilistic assessment of HE initiation scenarios. This work attempts to use probabilistic information that is available from both historic and ongoing tests to develop a basis for such assessment. Current PSTC approaches start with the functional form of the James Initiation Criterion as a backbone, and generalize to include varying areas of initiation and provide a probabilistic response based on test data for 1.8 g/cc (Ultrafine) 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) and LX-17 (92.5% TATB, 7.5% Kel-F 800 binder). Application of the PSTC methodology is presented investigating the safety and performance of a flying plate detonator and the margin of an Ultrafine TATB booster initiating LX-17.

Gresshoff, M; Hrousis, C A

2010-03-09

350

Solar urticaria: studies on mechanisms of tolerance.  

PubMed

The mechanisms by which tolerance is induced in solar urticaria were investigated in two patients whose eruptions were induced by wavelengths in the range 320-455 nm in one patient and 400-495 nm in another. Tolerance to radiation was induced by repeated exposures of the skin to the eliciting wavelengths of light. Weal and flare responses to intradermal injections of histamine and the histamine-releasing agent (codeine) were unaltered in the tolerant skin when compared with adjacent normal skin. Intradermal injection of in vitro irradiated serum or plasma from the patients induced an urticarial reaction in the unexposed skin but not in tolerant skin and repeated injections induced tolerance to the eliciting radiation. The results suggest that tolerance is not due to exhaustion of the photoallergen in the skin, or to an increase of the mast-cell degranulation threshold caused by exposure to ultraviolet radiation, or mast-cell mediator depletion, or histamine tachyphylaxis. It is likely that binding sites of IgE on mast cells remain occupied by the photoallergen during the state of tolerance, and that histamine release from mast cells is blocked. PMID:2354112

Leenutaphong, V; Hölzle, E; Plewig, G

1990-05-01

351

Fear of pain in orofacial pain patients  

Microsoft Academic Search

In the present study, we examined whether fear of pain, dental fear, general indices of psychological distress, and self-reported stress levels differed between 40 orofacial pain patients and 40 gender and age matched control general dental patients. We also explored how fear of pain, as measured by the Fear of Pain Questionnaire-III (J Behav Med 21 (1998) 389), relates to

Daniel W McNeil; Anthony R Au; Michael J Zvolensky; Deborah Rettig McKee; Iven J Klineberg; Christopher C. K Ho

2001-01-01

352

Risk Factor Assessment for Problematic Use of Opioids for Chronic Pain  

Microsoft Academic Search

Opioid analgesics provide effective treatment for noncancer pain, but many health providers have concerns about cognitive effects, tolerance, dependence, and addiction. Misuse of opioids is prominent in patients with chronic pain and early recognition of misuse risk could help providers offer adequate patient care while implementing appropriate levels of monitoring to reduce aberrant drug-related behaviors. Many persons with chronic pain

Robert N. Jamison; Robert R. Edwards

2012-01-01

353

Acceptance- versus Change-Based Pain Management: The Role of Psychological Acceptance  

ERIC Educational Resources Information Center

|This study compared two theoretically opposed strategies for acute pain management: an acceptance-based and a change-based approach. These two strategies were compared in a within-subjects design using the cold pressor test as an acute pain induction method. Participants completed a baseline pain tolerance assessment followed by one of the two…

Blacker, Kara J.; Herbert, James D.; Forman, Evan M.; Kounios, John

2012-01-01

354

Opioids in non-cancer pain: a life-time sentence?  

Microsoft Academic Search

There is continuing reluctance to prescribe strong opioids for the management of chronic non-cancer pain due to concerns about side-effects, physical tolerance, withdrawal and addiction. Randomized controlled trials have now provided evidence for the efficacy of opioids against both nociceptive and neuropathic pain. However, there is considerable variability in response rates, possibly depending on the type of pain, the type

Paul L. I. Dellemijn

2001-01-01

355

Barriers to pain management in a community sample of Chinese American patients with cancer.  

PubMed

Barriers to cancer pain management can contribute to the undertreatment of cancer pain. No studies have documented barriers to cancer pain management in Chinese American patients. The purposes of this study in a community sample of Chinese Americans were to: describe their perceived barriers to cancer pain management; examine the relationships between these barriers and patients' ratings of pain intensity, pain interference with function, mood disturbances, education, and acculturation level; and determine which factors predicted barriers to cancer pain management. Fifty Chinese Americans with cancer pain completed the following instruments: Brief Pain Inventory (BPI), Karnofsky Performance Status (KPS) Scale, Barriers Questionnaire (BQ), Hospital Anxiety and Depression Scale (HADS), Suinn-Lew Asian Self-Identity Acculturation Scale (SL-ASIA), and a demographic questionnaire. The mean total BQ score was in the moderate range. The individual barriers with the highest scores were: tolerance to pain medicine; time intervals used for dosage of pain medicine; disease progression; and addiction. Significant correlations were found between the tolerance subscale and least pain (r=0.380) and the religious fatalism subscale and average pain (r=0.282). These two subscales were positively correlated with anxiety and depression levels: (tolerance: r=0.282, r=0.284, respectively; religious fatalism: r=0.358, r=0.353, respectively). The tolerance subscale was positively correlated with pain interference (r=0.374). Approximately 21% of the variance in the total BQ score was explained by patients' education level, acculturation score, level of depression, and adequacy of pain treatment. Chinese American cancer patients need to be assessed for pain and perceived barriers to cancer pain management to optimize pain management. PMID:19004613

Edrington, Janet; Sun, Angela; Wong, Candice; Dodd, Marylin; Padilla, Geraldine; Paul, Steven; Miaskowski, Christine

2008-11-12

356

Threshold Concepts and Information Literacy  

ERIC Educational Resources Information Center

|What do we teach when we teach information literacy in higher education? This paper describes a pedagogical approach to information literacy that helps instructors focus content around transformative learning thresholds. The threshold concept framework holds promise for librarians because it grounds the instructor in the big ideas and underlying…

Townsend, Lori; Brunetti, Korey; Hofer, Amy R.

2011-01-01

357

The Nature of Psychological Thresholds  

ERIC Educational Resources Information Center

|Following G. T. Fechner (1966), thresholds have been conceptualized as the amount of intensity needed to transition between mental states, such as between a states of unconsciousness and consciousness. With the advent of the theory of signal detection, however, discrete-state theory and the corresponding notion of threshold have been discounted.…

Rouder, Jeffrey N.; Morey, Richard D.

2009-01-01

358

Density estimation by wavelet thresholding  

Microsoft Academic Search

Density estimation is a commonly used test case for nonparametric estimation methods. We explore the asymptotic properties of estimators based on thresholding of empirical wavelet coefficients. Minimax rates of convergence are studied over a large range of Besov function classes $B_{\\\\sigma pq}$ and for a range of global $L'_p$ error measures, $1 \\\\leq p' < \\\\infty$. A single wavelet threshold

David L. Donoho; Iain M. Johnstone; Gérard Kerkyacharian; Dominique Picard

1996-01-01

359

Threshold Hypothesis: Fact or Artifact?  

ERIC Educational Resources Information Center

|The threshold hypothesis (TH) assumes the existence of complex relations between creative abilities and intelligence: linear associations below 120 points of IQ and weaker or lack of associations above the threshold. However, diverse results have been obtained over the last six decades--some confirmed the hypothesis and some rejected it. In this…

Karwowski, Maciej; Gralewski, Jacek

2013-01-01

360

Thermotactile Perception Thresholds Measurement Conditions  

Microsoft Academic Search

The purpose of this paper is to investigate the effects of posture, push force and rate of temperature change on thermotactile thresholds and to clarify suitable measuring conditions for Japanese people. Thermotactile (warm and cold) thresholds on the right middle finger were measured with an HVLab thermal aesthesiometer. Subjects were eight healthy male Japanese students. The effects of posture in

Setsuo MAEDA; Hisataka SAKAKIBARA

2002-01-01

361

Threshold Hypothesis: Fact or Artifact?  

ERIC Educational Resources Information Center

The threshold hypothesis (TH) assumes the existence of complex relations between creative abilities and intelligence: linear associations below 120 points of IQ and weaker or lack of associations above the threshold. However, diverse results have been obtained over the last six decades--some confirmed the hypothesis and some rejected it. In this…

Karwowski, Maciej; Gralewski, Jacek

2013-01-01

362

Plant salt tolerance  

Microsoft Academic Search

Soil salinity is a major abiotic stress in plant agriculture worldwide. This has led to research into salt tolerance with the aim of improving crop plants. However, salt tolerance might have much wider implications because transgenic salt-tolerant plants often also tolerate other stresses including chilling, freezing, heat and drought. Unfortunately, suitable genetic model systems have been hard to find. A

Jian-Kang Zhu

2001-01-01

363

Chronic intraoral pain--assessment of diagnostic methods and prognosis.  

PubMed

The overall goal of this thesis was to broaden our knowledge of chronic intraoral pain. The research questions were: What methods can be used to differentiate inflammatory, odontogenic tooth pain from pain that presents as toothache but is non-odontogenic in origin? What is the prognosis of chronic tooth pain of non-odontogenic origin, and which factors affect the prognosis? Atypical odontalgia (AO) is a relatively rare but severe and chronic pain condition affecting the dentoalveolar region. Recent research indicates that the origin is peripheral nerve damage: neuropathic pain. The condition presents as tooth pain and is challenging to dentists because it is difficult to distinguish from ordinary toothache due to inflammation or infection. AO is of interest to the pain community because it shares many characteristics with other chronic pain conditions, and pain perpetuation mechanisms are likely to be similar. An AO diagnosis is made after a comprehensive examination and assessment of patients' self-reported characteristics: the pain history. Traditional dental diagnostic methods do not appear to suffice, since many patients report repeated care-seeking and numerous treatment efforts with little or no pain relief. Developing methods that are useful in the clinical setting is a prerequisite for a correct diagnosis and adequate treatment decisions. Quantitative sensory testing (QST) is used to assess sensory function on skin when nerve damage or disease is suspected. A variety of stimuli has been used to examine the perception of, for example, touch, temperature (painful and non-painful), vibration, pinprick pain, and pressure pain. To detect sensory abnormalities and nerve damage in the oral cavity, the same methods may be possible to use. Study I examined properties of thermal thresholds in and around the mouth in 30 pain-free subjects: the influence of measurement location and stimulation area size on threshold levels, and time variability of thresholds. Thresholds for cold, warmth and painful heat were measured in four intraoral and two extraoral sites. Measurements were repeated 3 times over 6 weeks, using four sizes of stimulation area (0.125-0.81 cm2). The threshold levels were highly dependent on location but less dependent on measuring probe size and time variability was small, and this knowledge is important for the interpretation of QST results. Study II applied a recently developed standardized QST examination protocol (intended for use on skin) inside the oral cavity. Two trained examiners evaluated 21 pain-free subjects on three occasions over 1-3 weeks, at four sites-three intraoral and one extraoral. Most tests had acceptable reliability and the original test instruments and techniques could be applied intraorally with only minor adjustments. Study III examined the value of cone-beam computed tomography (CBCT) in pain investigations. Twenty patients with AO and 5 with symptomatic apical periodontitis (inflammatory tooth pain) participated. The results indicate that when AO is suspected, addition of CBCT can improve the diagnostic certainty compared to sole use of periapical and panoramic radiographs, especially because of the superior ability of CBCT to exclude inflammation as the pain cause. Study IV assessed the long-term prognosis of AO, and analyzed potential outcome predictors. A comprehensive questionnaire including validated and reliable instruments was used to gather data on patient and pain characteristics and pain consequences from 37 patients in 2002 and 2009. Thirty-five percent of the patients reported substantial overall improvement at follow-up, but almost all still had pain of some degree after many years. The initial high level of emotional distress was unchanged. Low baseline pain intensity predicted improvement over time. PMID:22338784

Pigg, Maria

2011-01-01

364

Ecohydrology on the Threshold?  

NASA Astrophysics Data System (ADS)

This presentation suggests that there are three major limitations to the development of ecohydrology as a coherent disciplinary area. One of the principal controls and feedbacks on patterns of plants and water in the environment is the form of the landscape and landscape-forming processes. Yet (eco)geomorphology is typically overlooked as a topic for ecohydrological investigation. Thus, the process domains used to explain patterns is typically overly restricted. As surface change controls the connectivity of other process, this restriction is significant. However, even when surface change is incorporated, there is often an emphasis on subdisciplinary areas, so that the investigation of patterns across process domains is not carried out in a holistic way. For example, studies of the feedbacks of vegetation on flow resistance are carried out significantly differently when considering wind and water flows (and indeed differently for water flows on hillslopes compared to in channels). Human action is the most important global control on ecohydrology, either from a top-down perspective through climate change, or from a bottom-up perspective through land use and land-use change. The actions of people on ecohydrological and ecogeomorphic processes, though, are typically considered in a static way. Techniques of agent-based modelling are being developed to overcome this limitation, but there need to be parallel developments in field techniques to address the data requirements and empirical underpinnings of such approaches. I argue that to cross the threshold into becoming a more mature discipline ecohydrology/ecogeomorphology needs to take on board the limitations of representations of process, pattern and people. Using examples from studies of land degradation in drylands, as well as from more temperate settings, I will suggest how progress may start to be made.

Wainwright, John

2013-04-01

365

Techniques for assessing knee joint pain in arthritis  

PubMed Central

The assessment of pain is of critical importance for mechanistic studies as well as for the validation of drug targets. This review will focus on knee joint pain associated with arthritis. Different animal models have been developed for the study of knee joint arthritis. Behavioral tests in animal models of knee joint arthritis typically measure knee joint pain rather indirectly. In recent years, however, progress has been made in the development of tests that actually evaluate the sensitivity of the knee joint in arthritis models. They include measurements of the knee extension angle struggle threshold, hind limb withdrawal reflex threshold of knee compression force, and vocalizations in response to stimulation of the knee. A discussion of pain assessment in humans with arthritis pain conditions concludes this review.

Neugebauer, Volker; Han, Jeong S; Adwanikar, Hita; Fu, Yu; Ji, Guangchen

2007-01-01

366

Urologic myofascial pain syndromes  

Microsoft Academic Search

Treatment of pain of urogenital origin, chronic pelvic pain syndrome, can be frustrating for patients and physicians. The\\u000a usual approaches do not always produce the desired results. Visceral pain from pelvic organs and myofascial pain from muscle\\u000a trigger points share common characteristics. Referred pain from myofascial trigger points can mimic visceral pain syndromes\\u000a and visceral pain syndromes can induce trigger

Ragi Doggweiler-Wiygul

2004-01-01

367

Opioid-induced hyperalgesia and burn pain.  

PubMed

The treatment of pain produced during the management of burn injury has been an ongoing problem for physicians caring for these patients. The main therapeutic option for analgesia has been the repeated and prolonged use of opioids. The adverse effects of opioids are well known but the long term use of opioids which produces tolerance with accompanying dose escalation and dependence is most problematic. Another potentially important consequence of opioid exposure that sometimes masks as tolerance is that of opioid induced hyperalgesia. This syndrome is manifest as enhanced pain, sensitivity and loss of analgesic efficacy in patients treated with opioids who actually become sensitized to painful stimuli. This article focuses on the treatment of burn pain and how current analgesic therapies with opioids may cause hyperalgesia and affect the adequacy of treatment for burn pain. This article also provides possible modalities to help therapeutically manage these patients and considers future analgesic strategies which may help to improve pain management in this complicated patient population. PMID:23143613

Holtman, Joseph R; Jellish, W Scott

368

Painful hypoadrenalism  

PubMed Central

A 61-year-old man presented with diffuse myalgia and arthralgia. The physical examination showed diffuse musculoskeletal tenderness and joint stiffness without the presence of synovitis or arthritis. Nerve conduction study showed combined mild axonal degenerative and demyelinating change. Muscle biopsy analysis showed unspecific mild muscle atrophy with myopathic changes found on electromyography. A diagnosis of isolated adrenocorticotropic hormone deficiency was made on the basis of endocrinological evaluation. The widespread musculoskeletal pain resolved as a result of administration of physiological dose of hydrocortisone replacement. In a patient with unexplained rheumatic symptoms, adrenocortical insufficiency should be considered in the possible aetiology.

Hoshino, Chisho; Satoh, Noriyuki; Narita, Masashi; Kikuchi, Akio; Inoue, Minoru

2011-01-01

369

Taking Sides with Pain - Lateralization aspects Related to Cerebral Processing of Dental Pain  

PubMed Central

The current fMRI study investigated cortical processing of electrically induced painful tooth stimulation of both maxillary canines and central incisors in 21 healthy, right-handed volunteers. A constant current, 150% above tooth specific pain perception thresholds was applied and corresponding online ratings of perceived pain intensity were recorded with a computerized visual analog scale during fMRI measurements. Lateralization of cortical activations was investigated by a region of interest analysis. A wide cortical network distributed over several areas, typically described as the pain or nociceptive matrix, was activated on a conservative significance level. Distinct lateralization patterns of analyzed structures allow functional classification of the dental pain processing system. Namely, certain parts are activated independent of the stimulation site, and hence are interpreted to reflect cognitive emotional aspects. Other parts represent somatotopic processing and therefore reflect discriminative perceptive analysis. Of particular interest is the observed amygdala activity depending on the stimulated tooth that might indicate a role in somatotopic encoding.

Brugger, Mike; Ettlin, Dominik A.; Meier, Michael; Keller, Thierry; Luechinger, Roger; Barlow, Ashley; Palla, Sandro; Jancke, Lutz; Lutz, Kai

2010-01-01

370

Thermal sensitivity is not changed by acute pain or afferent stimulation.  

PubMed Central

The effect of conditioning stimulation on thermal sensitivity and clinical pain was studied in 40 patients and six healthy subjects. Thresholds regarding cold, warm and heat pain perception did not differ significantly between the painful and non-painful skin areas in patients or between patients and healthy subjects before stimulation. The patients received either 100 Hz TENS, 2 Hz TENS, 100 Hz vibration, or placebo. No significant changes in thermal sensitivity were observed during and after conditioning stimulation in any of the test groups, although 24/40 (60%) of the patients reported reduction of their clinical pain intensity. The results indicate that (a) thermal sensitivity is not influenced by the presence of clinical pain, (b) the effects of stimulation on thermal sensitivity (thresholds) and clinical pain are not closely related, (c) central inhibitory effects of TENS and vibration are crucial for their pain relieving capacity.

Ekblom, A; Hansson, P

1987-01-01

371

Electrical tolerance of the Chara corallina plasmalemma  

SciTech Connect

(Ca2+)o controls at least three distinct electrical phenomena in the Chara plasmalemma. 1). Increase of the electrical tolerance. 2). Decrease of the G without a marked change of the Gp/Gd ratio. 3). Elevation of the threshold for excitation. On the other hand, (Mg2+)o shows quite opposite effects. Thus, optimum (Ca2+)o and (Mg2+)o are expected in vivo. Voltage dependencies of various conductances in the Chara plasmalemma are schematically shown.

Ohkawa, T.; Tsutsui, I.

1988-01-01

372

Differences in suprathreshold heat pain responses and self-reported sleep quality between patients with temporomandibular joint disorder and healthy controls  

PubMed Central

The purpose of this study was to examine differences in heat pain threshold (HPTh) and heat pain tolerance (HPTo) between temporomandibular joint disorder (TMJD) patients and healthy controls. Using suprathreshold heat pain, this study also examined between-group (i.e. TMJD vs. healthy controls) differences in hyperalgesia and temporal summation (TS) of heat pain. Lastly, whether between-group differences in these heat pain outcomes were mediated by self-reported sleep quality was also tested. A total of 119 participants (41% TMJD) completed the current study. HPTh and HPTo responses were assessed at the ventral forearm with an ascending method of limits, while hyperalgesia and TS responses were assessed at the dorsal forearm at temperatures of 46, 48 and 50 °C. Prior to completion of heat pain procedures, participants completed the Pittsburgh Sleep Quality Index. Significant between-group differences in HPTh and HPTo were not observed. TMJD patients demonstrated significantly greater hyperalgesia than healthy controls at 46 °C only, but there were no differences for TS. Furthermore, TMJD patients reported significantly poorer sleep quality compared with healthy controls. Data analysis revealed a significant simple mediation effect whereby the presence of TMJD was strongly associated with poorer self-reported sleep quality, which, in turn, was related to enhanced hyperalgesia at 46 °C. These findings support the hypothesis that the thermal hyperalgesia demonstrated by TMJD patients may be related to poor quality of their self-reported sleep. The ability of interventions that improve sleep quality to also affect pain sensitivity is currently the topic of ongoing investigation.

Ribeiro-Dasilva, M.C.; Goodin, B.R.; Fillingim, R.B.

2013-01-01

373

Fault tolerance with noisy and slow measurements and preparation.  

PubMed

It is not so well known that measurement-free quantum error correction protocols can be designed to achieve fault-tolerant quantum computing. Despite their potential advantages in terms of the relaxation of accuracy, speed, and addressing requirements, they have usually been overlooked since they are expected to yield a very bad threshold. We show that this is not the case. We design fault-tolerant circuits for the 9-qubit Bacon-Shor code and find an error threshold for unitary gates and preparation of p((p,g)thresh)=3.76×10(-5) (30% of the best known result for the same code using measurement) while admitting up to 1/3 error rates for measurements and allocating no constraints on measurement speed. We further show that demanding gate error rates sufficiently below the threshold pushes the preparation threshold up to p((p)thresh)=1/3. PMID:20867497

Paz-Silva, Gerardo A; Brennen, Gavin K; Twamley, Jason

2010-08-30

374

Optimal thresholding for color images  

NASA Astrophysics Data System (ADS)

Color image thresholding is a special case of color clustering which is commonly used for tasks such as object detection, region segmentation, enhancement, and target tracking. As compared to the three-dimensional (3-D) color clustering, thresholding is computationally more efficient for computer implementation and pipelined hardware realization. Traditionally, this method operates on a particular color component whose distribution possesses more prominent peaks than the other two color histograms. In this operation, it is expected that the histogram peaks represent meaningful object areas. However, the color component thresholding results are less reliable than those of 3-D clustering because the valuable information in the other two color components are ignored in region acceptance process. To improve the performance of thresholding, we describe a method that thresholds an input image three times on three different color components independently. The best thresholds are selected by optimizing the within-group variance or directed divergence measure for red, green, and blue distributions separately. The resultant three binary images are combined by means of a predicate logic function that makes use of a 3-input, 1-output majority logic gate. This enables 1-D thresholding mechanism to incorporate the information on all the color components in region acceptance process.

Celenk, Mehmet; Uijt de Haag, Maarten

1998-04-01

375

Bayesian estimation of dose thresholds.  

PubMed

An example is described of Bayesian estimation of radiation absorbed dose thresholds (subsequently simply referred to as dose thresholds) using a specific parametric model applied to a data set on mice exposed to 60Co gamma rays and fission neutrons. A Weibull based relative risk model with a dose threshold parameter was used to analyse, as an example, lung cancer mortality and determine the posterior density for the threshold dose after single exposures to 60Co gamma rays or fission neutrons from the JANUS reactor at Argonne National Laboratory. The data consisted of survival, censoring times and cause of death information for male B6CF1 unexposed and exposed mice. The 60Co gamma whole-body doses for the two exposed groups were 0.86 and 1.37 Gy. The neutron whole-body doses were 0.19 and 0.38 Gy. Marginal posterior densities for the dose thresholds for neutron and gamma radiation were calculated with numerical integration and found to have quite different shapes. The density of the threshold for 60Co is unimodal with a mode at about 0.50 Gy. The threshold density for fission neutrons declines monotonically from a maximum value at zero with increasing doses. The posterior densities for all other parameters were similar for the two radiation types. PMID:12593429

Groer, P G; Carnes, B A

2003-01-01

376

Finding thresholds for image segmentation  

NASA Astrophysics Data System (ADS)

Segmentation methods for images often have cost functions which evaluate the (dis)similarity between pixels or segments. Thresholds on cost values are then used to decide whether or not to grow, join or split segments. The results for a given image critically depend on the selection of the threshold values. In remote sensing, a too low threshold will split up regions of constant ground cover and a too high threshold will join adjacent regions of different ground cover. Optimal thresholds can be determined using different classes of methods: generating cost value distributions from the original image; obtaining statistical distributions from segmented images; comparing a 'true' segmentation with the results of segmentation using a range of thresholds. A so-called 'true' segmentation can be derived from human expert segmentations or from maps obtained by ground surveys or segmentation of higher resolution images. Also artificial images can be generated having the advantage that the segmentation is known to sub-pixel level. Several methods for threshold determination are described for a hybrid segmentation method developed by us. Measures are described for comparison of two segmentations. Results are evaluated using several (parts of) LANDSAT images and artificial generated images.

Schouten, Theo E.; Klein Gebbinck, Maurice S.; Schoenmakers, Ron P.; Wilkinson, Graeme G.

1994-12-01

377

Development of mechanical and thermal nociceptive threshold testing devices in unrestrained birds (broiler chickens).  

PubMed

Behavioural signs of pain are difficult to quantify and interpret in animals. Nociceptive threshold testing is therefore a useful method for examining the perception and processing of noxious stimuli underlying pain states. Devices were developed to measure response thresholds to quantified, ramped mechanical and thermal nociceptive stimuli applied to the leg or keel of unrestrained birds. Up to 9N mechanical force was delivered via a single round-ended 2mm pin using a pneumatic actuator at 0.4Ns(-1). Heat was applied through a small copper element at 0.8°Cs(-1) to a maximum of 50°C. The repeatability and reliability of threshold measures were validated using 10-12 broiler chickens (aged 49-66 days) per site and modality. Mechanical threshold, or skin and threshold temperature, were recorded over three sessions across a 36h period. Both stimulus types elicited clear, reproducible behavioural responses. Mechanical threshold means and 95% confidence intervals were 3.0 (2.8-3.2)N for keel and 2.0 (1.8-2.1)N for leg sites. Keel thermal tests gave a mean skin temperature of 39.3 (39.1-39.5)°C, and threshold of 46.8 (46.6-47.1)°C. Leg skin temperature was 35.7 (35.6-35.9)°C and threshold 42.5 (42.2-42.8)°C. Threshold measures were consistent within and across sessions and birds showed individual repeatability across tests within sessions. Individual birds' mechanical keel thresholds were also repeatable across sessions. The apparatus gave reliable, reproducible measurements of thresholds to noxious mechanical and thermal stimuli. The range recorded was comparable with previously published nociceptor thresholds in dissected chicken nerve filament fibres, and the method appears suitable for studying nociceptive processes in broiler chickens. PMID:21843551

Hothersall, B; Caplen, G; Nicol, C J; Taylor, P M; Waterman-Pearson, A E; Weeks, C A; Murrell, J C

2011-08-06

378

When Sex Is Painful  

MedlinePLUS

How common is painful sex? Pain during intercourse is very common—nearly 3 out of 4 women have pain during intercourse at some time during ... a long-term problem. What causes pain during sex? Pain during sex may be a sign of ...

379

Low Back Pain  

MedlinePLUS

MENU Return to Web version 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 ...

380

Pain in orthodontics  

Microsoft Academic Search

This literature review focuses on previous studies of pain and pain perception in dentistry with special emphasis on orthodontic treatment. The prevalence of pain and background factors such as age, gender and culture\\/society, in addition to pain physiology and the influence of concomitant emotional and cognitive factors, is examined. Pain during orthodontic tooth movement is reported from the point of

Marianne Bergius; Stavros Kiliaridis; Ulf Berggren

2000-01-01

381

Extracephalic Yawning Pain  

Microsoft Academic Search

The aim of this study was to report on two patients with recurrent, paroxysmal, extracephalic pain triggered by yawning. Pain with yawning may occur in several conditions (secondary yawning pain) or develop in the absence of precipitating lesions (primary yawning pain). Primary yawning pain is normally of cephalic location. Methods used were clinical neurological examinations, magnetic resonance imaging of the

DE Jacome

2004-01-01

382

Gabapentin in Pain Management  

Microsoft Academic Search

role of gabapentin in pain treatment will be discussed with an attempt to identify pain symptoms that are likely to be responsive to gabapentin; 2) animal stud- ies of gabapentin on neuropathic pain and other pain behaviors will be evaluated; and 3) possible mecha- nisms of gabapentin actions will be considered in re- lation to mechanisms of neuropathic pain in

Jianren Mao; Lucy L. Chen

2000-01-01

383

Responses to pain in school-aged children with experience in a neonatal intensive care unit: Cognitive aspects and maternal influences  

Microsoft Academic Search

Previously, it was shown that school-aged (9–14yr) preterm and fullterm children with neonatal pain exposure exhibit elevated heat pain thresholds and heightened perceptual sensitization to tonic painful heat when tested under standard conditions [Hermann C, Hohmeister J, Demirakca S, Zohsel K, Flor H. Long-term alteration of pain sensitivity in school-aged children with early pain experiences. Pain 2006;125:278–85]. Here, changes in

Johanna Hohmeister; Süha Demirakça; Katrin Zohsel; Herta Flor; Christiane Hermann

2009-01-01

384

A direct comparison of affective pain processing underlying two traditional pain modalities in rodents.  

PubMed

In the preclinical study of pain, two commonly used pain models are the L5 spinal nerve ligation (SNL) and the injection of carrageenan. Using a modified place escape/avoidance paradigm (mPEAP), a novel behavioral test that quantifies aversive behavior evoked by painful stimuli, we directly compared the affective component of the SNL and inflammation models. Fifty three Sprague-Dawley rats underwent baseline mechanical paw withdrawal threshold (MPWT) and mPEAP testing followed by an L5 SNL or sham surgery for the left paw and then a carrageenan or saline injection for the right paw. After recovering, animals underwent post-manipulation MPWT and mPEAP tests. Both pain conditions produced mechanical hypersensitivity, and animals with a single-paw condition demonstrated escape/avoidance behavior in response to stimulation of the affected paw. Animals with the bilateral pain condition did not show a preference for stimulation of one paw versus the other paw, and the avoidance behavior was not significantly different from the sham/saline control. The results indicate that the pain models are associated with significant avoidance behavior and that they produce comparable degrees of pain affect. These findings advance the preclinical study of pain by validating the simultaneous utilization of the SNL and inflammation models and will allow future studies that combine pain conditions to more closely resemble clinical conditions. PMID:22172927

McNabb, C T; Uhelski, M L; Fuchs, P N

2011-12-06

385

Fentanyl buccal tablet: rapid relief from breakthrough pain.  

PubMed

Breakthrough pain--a transient increase in pain occurring over a baseline of controlled persistent pain--represents an important clinical challenge in the management of cancer and other chronic pain conditions. The fentanyl buccal tablet is a new sugar-free, easily-administered formulation that uses an effervescent drug delivery system to enhance the rate and extent of fentanyl absorption across the buccal mucosa. Clinical trials indicate that the rapid systemic exposure provided by fentanyl buccal tablets translates into clinically significant improvements in pain intensity. Pain relief is observed within 10-15 min of administration. Fentanyl buccal tablets are generally well tolerated, with the most commonly observed adverse events being typical opioid side effects. Fentanyl buccal tablets represent a convenient and effective treatment for the control of breakthrough pain. PMID:18001263

Taylor, Donald R

2007-12-01

386

Pharmacotherapy for breakthrough cancer pain.  

PubMed

Breakthrough pain (BTP) is a transient exacerbation of pain that occurs either spontaneously, or in relation to a specific predictable or unpredictable trigger, despite relatively stable and adequately controlled background pain. The principal pharmacological treatment of BTP is represented by the administration of opioids as needed. Oral opioids have traditionally been the only available drugs for BTP. However, the onset and duration of action of oral opioids such as morphine or oxycodone may not be suitable for treating many episodes of BTP that are of short onset and duration. Transmucosal administration of lipophilic substances has gained a growing popularity in recent years due to the rapid effect, clinically observable 10-15 minutes after drug administration, and the non-invasive form. Different technologies have been developed to provide fast pain relief with potent opioid drugs such fentanyl, delivered by non-invasive routes (rapid onset opioids, ROOs). All the studies performed with ROOs have recommended that these drugs should be administered to opioid-tolerant patients receiving doses of oral morphine equivalents of at least 60?mg. These preparations, including oral transmucosal fentanyl citrate, fentanyl buccal tablet, sublingual fentanyl, intranasal fentanyl spray, fentanyl-pectin nasal spray and fentanyl buccal soluble film have shown better efficacy than placebo or oral opioids. Long-term studies have confirmed their efficacy and safety. PMID:22233484

Mercadante, Sebastiano

2012-01-22

387

Influence of Pain Signal on Pain Threshold and Brain Norepinephrine and 5-Hydroxytryptamine Concentration.  

National Technical Information Service (NTIS)

Many reports have been published on the relationship between emotion and monoamine neurotransmitters. It is known that when people are excited the catecholamines and such metabolites in their urine increase. In animals, the level of brain monoamines, espe...

C. Tang W. Lin L. Sun

1978-01-01

388

Imipramine decreases oesophageal pain perception in human male volunteers  

PubMed Central

Department of Medicine, Suite 501, Pepper Pavilion, Allegheny University Hospitals, Graduate, One Graduate Plaza, 1800 Lombard Street, Philadelphia, Pennsylvania 19146, USA Correspondence to: Dr D O Castell. Accepted for publication 19 January 1998 Background—Visceral hyperalgesia is a hallmark of functional gastrointestinal disorders. Antidepressants improve symptoms in these patients, although their mode of action is unclear. Antidepressant, anticholinergic, and analgesic mechanisms have been proposed. ?Aims—To investigate whether imipramine, which has a visceral analgesic effect, increases pain thresholds to experimental visceral pain. ?Methods—Visceral perception for first sensation and pain was measured with intraoesophageal balloon distension in 15 male volunteers. The effect of imipramine was studied in a double blind, placebo controlled, crossover study. Imipramine was given in ascending doses for 12 days (25 mg days 1-3, 50 mg days 4-6, 75 mg days 7-12), with oesophageal perception studied on day 13. ?Results—Inflation volumes and intraballoon pressures at first sensation were not different between placebo and imipramine. Balloon inflation volume at pain threshold was higher on imipramine (p=0.015). Median intraballoon pressures were not different at pain threshold for placebo and imipramine. Oesophageal wall compliance was not affected by imipramine. ?Conclusion—Increased pain thresholds on imipramine in this group of normal male volunteers in the absence of changes in oesophageal tone imply the presence of a visceral analgesic effect. ?(GUT 1998;:807-813)? Keywords: antidepressants;  imipramine;  visceral hyperalgesia;  oesophageal balloon;  distension;  functional bowel syndromes

Peghini, P; Katz, P; Castell, D

1998-01-01

389

Role of Anticipatory Anxiety and Anxiety Sensitivity in Children's and Adolescents' Laboratory Pain Responses  

PubMed Central

Objective To examine relationships among trait anxiety sensitivity, state task-specific anticipatory anxiety, and laboratory pain responses in healthy children and adolescents. Methods Participants (N=118, 49.2% female, ages 8-18 years) completed a measure of anxiety sensitivity and rated anticipatory anxiety prior to undergoing thermal, pressure, and cold pain tasks. Linear and logistic regressions were used to test the hypothesis that anxiety sensitivity and anticipatory anxiety would predict incremental variance in pain response after controlling for sex, age, and anxious symptoms. Results Anticipatory anxiety accounted for 35-38% of unique variance in pain report across tasks, and 10% of unique variance in thermal tolerance. Anxiety sensitivity was unrelated to pain responses. Conclusions Task-specific anxiety is an important predictor of pain report and, in certain cases, pain tolerance. Interventions designed to reduce task-specific anticipatory anxiety may help reduce pain responses in children and adolescents.

Tsao, Jennie C. I.; Myers, Cynthia D.; Craske, Michelle G.; Bursch, Brenda; Kim, Su C.; Zeltzer, Lonnie K.

2008-01-01

390

Harmonic Analysis of Polynomial Threshold Functions  

Microsoft Academic Search

The analysis of linear threshold Boolean functions has recently attracted the attention of those interested in circuit complexity as well as of those interested in neural networks. Here a generalization of linear threshold functions is defined, namely, polynomial threshold functions, and its relation to the class of linear threshold functions is investigated. A Boolean function is polynomial threshold if it

Jehoshua Bruck

1990-01-01

391

A study of wavelet thresholding denoising  

Microsoft Academic Search

This paper introduces the principle of wavelet multiresolution analysis. Four kinds of threshold selection rules and three methods of threshold processing are given. According to the computer simulation, the best rule of estimating the threshold is found, which is combined with three kinds of threshold processing methods to denoise the same noisy signal. The best method of threshold processing is

Dai-Fei Guo; Wei-Hong Zhu; Zhen-Ming Gao; Jian-Qiang Zhang

2000-01-01

392

Methylprednisolone prevents the development of autotomy and neuropathic edema in rats, but has no effect on nociceptive thresholds  

Microsoft Academic Search

Corticosteroids are probably an effective treatment for some types of neuropathic pain and complex regional pain syndromes. This study examined the effects of systemic methylprednisolone (MP) on acute nociception and on pain behavior and hyperalgesia in normal and neuropathic rats. There was no dose-response to intraperitoneal MP (up to 12 mg\\/kg) for nociceptive thresholds to heat (Peltier) or mechanical (analgesy-meter

Wade S. Kingery; Juan M. Castellote; Mervyn Maze

1999-01-01

393

[Is postoperative pain only a nociceptive pain?].  

PubMed

More than 75% of patients undergoing surgery suffer from acute pain. Most of this pain transforms into chronic pain. Currently, treatment of postoperative pain is based mainly on opioids, but results are not quite satisfactory. Postoperative pain is defined as a condition of tissue injury together with muscle spasm after surgery. Recently, peripheral and central sensitization has been shown within the mechanisms of postoperative pain generation. Accordingly, anti-convulsive drugs have been used successfully for the treatment of postoperative pain. Therefore, the issue of whether postoperative pain is purely a nociceptive pain remains a topic of debate. Considering that every surgical intervention might result in a nerve injury, it is not surprising to find neuropathic pain features within the postoperative pain itself. In light of these findings, it would be more precise to define postoperative pain as a combination of inflammatory and neuropathic components instead of as pure pain. Thus, the appropriate postoperative treatment should be planned involving both of these components. PMID:20582745

Ceyhan, Dilek; Güleç, Mehmet Sacit

2010-04-01

394

Sweet taste and menthol increase cough reflex thresholds.  

PubMed

Cough is a vital protective reflex that is triggered by both mechanical and chemical stimuli. The current experiments explored how chemosensory stimuli modulate this important reflex. Cough thresholds were measured using a single-inhalation capsaicin challenge. Experiment 1 examined the impact of sweet taste: Cough thresholds were measured after rinsing the mouth with a sucrose solution (sweet) or with water (control). Experiment 2 examined the impact of menthol: Cough thresholds were measured after inhaling headspace above a menthol solution (menthol vapor) or headspace above the mineral oil solvent (control). Experiment 3 examined the impact of rinsing the mouth with a (bitter) sucrose octaacetate solution. Rinsing with sucrose and inhaling menthol vapor significantly increased measured cough thresholds. Rinsing with sucrose octaacete caused a non-significant decrease in cough thresholds, an important demonstration of specificity. Decreases in cough reflex sensitivity from sucrose or menthol could help explain why cough syrups without pharmacologically active ingredients are often almost as effective as formulations with an added drug. Further, the results support the idea that adding menthol to cigarettes might make tobacco smoke more tolerable for beginning smokers, at least in part, by reducing the sensitivity of an important airway defense mechanism. PMID:22465565

Wise, Paul M; Breslin, Paul A S; Dalton, Pamela

2012-03-23

395

An effect of neutral collisions on the excitation threshold of electrostatic ion-cyclotron waves  

NASA Astrophysics Data System (ADS)

Laboratory experiments using a sodium plasma are reported that demonstrate a robustness of electrostatic ion-cyclotron waves in the presence of elevated neutral-helium pressure. It is found that the excitation threshold decreases with neutral pressure, and that, in the presence of a transverse localized electric field, the waves are able to tolerate much higher collisionality than previously believed. When the ion-neutral collision frequency and ion gyrofrequency are comparable, the excitation threshold is significantly smaller than its collisionless value.

Koepke, M. E.; Zintl, M. W.; Good, T. N.

396

Pain Management Programs  

MedlinePLUS

... in Cart : 0 Resource Guide to Chronic Pain Medications & Treatments The Art of Pain Management What We Have Learned Going to the ER Communication Tools Pain Management Programs Videos Resources Glossary FAQs ...

397

American Chronic Pain Association  

MedlinePLUS

... in Cart : 0 Resource Guide to Chronic Pain Medications & Treatments The Art of Pain Management What We Have Learned Going to the ER Communication Tools Pain Management Programs Videos Resources Glossary FAQs ...

398

Back Pain Prevention  

MedlinePLUS

KnowYourBack.org Success Stories Spinal Conditions Treatments Back Pain Prevention Lifestyle Choices Exercise Back Pack Safety Pregnancy and Back Pain Preventing Osteoporosis Back Pain Basics Book Brochures Spine in the News Definitions ...

399

What Is Back Pain?  

MedlinePLUS

... some types of treatments for chronic back pain. Hot or Cold Packs (or Both) Hot or cold packs can soothe sore, stiff backs. ... helps reduce swelling and numbs deep pain. Using hot or cold packs may relieve pain, but this ...

400

The nociceptive withdrawal reflex: normative values of thresholds and reflex receptive fields.  

PubMed

Assessments of spinal nociceptive withdrawal reflexes can be used in human research both to evaluate the effect of analgesics and explore pain mechanisms related to sensitization. Before the reflex can be used as a clinical tool, normative values need to be determined in large scale studies. The aim of this study was to determine the reference values of spinal nociceptive reflexes and subjective pain thresholds (to single and repeated stimulation), and of the area of the reflex receptive fields (RRF) in 300 pain-free volunteers. The influences of gender, age, height, weight, body-mass index (BMI), body side of testing, depression, anxiety, catastrophizing and parameters of Short-Form 36 (SF-36) were analyzed by multiple regressions. The 95% confidence intervals were determined for all the tests as normative values. Age had a statistically and quantitatively significant impact on the subjective pain threshold to single stimuli. The reflex threshold to single stimulus was lower on the dominant compared to the non-dominant side. Depression had a negative impact on the subjective pain threshold to single stimuli. All the other analyses either did not reveal statistical significance or displayed quantitatively insignificant correlations. In conclusion, normative values of parameters related to the spinal nociceptive reflex were determined. This allows their clinical application for assessing central hyperexcitability in individual patients. The parameters investigated explore different aspects of sensitization processes that are largely independent of demographic characteristics, cognitive and affective factors. PMID:19505833

Neziri, Alban Y; Andersen, Ole K; Petersen-Felix, Steen; Radanov, Bogdan; Dickenson, Anthony H; Scaramozzino, Pasquale; Arendt-Nielsen, Lars; Curatolo, Michele

2009-06-07

401

Optimum General Threshold Secret Sharing  

Microsoft Academic Search

An important issue of a secret sharing (SS) scheme is to minimize the entropy of a share. This issue is perfectly resolved for the simpler classes called (k,n)- threshold SS (TSS) scheme and (k,L,n)-threshold ramp SS (TRSS) scheme. That is, for these two classes, an opti- mum construction which minimizes the entropy of a share was presented. The goal of

Maki Yoshida; Toru Fujiwara; Marc Fossorier

2008-01-01

402

Threshold models in radiation carcinogenesis  

SciTech Connect

Cancer incidence and mortality data from the atomic bomb survivors cohort has been analyzed to allow for the possibility of a threshold dose response. The same dose-response models as used in the original papers were fit to the data. The estimated cancer incidence from the fitted models over-predicted the observed cancer incidence in the lowest exposure group. This is consistent with a threshold or nonlinear dose-response at low-doses. Thresholds were added to the dose-response models and the range of possible thresholds is shown for both solid tumor cancers as well as the different leukemia types. This analysis suggests that the A-bomb cancer incidence data agree more with a threshold or nonlinear dose-response model than a purely linear model although the linear model is statistically equivalent. This observation is not found with the mortality data. For both the incidence data and the mortality data the addition of a threshold term significantly improves the fit to the linear or linear-quadratic dose response for both total leukemias and also for the leukemia subtypes of ALL, AML, and CML.

Hoel, D.G.; Li, P. [Medical Univ. of South Carolina, Charleston, SC (United States). Dept. of Biometry and Epidemiology

1998-09-01

403

Spatial Variable Thresholding for SCALES  

NASA Astrophysics Data System (ADS)

The Stochastic Coherent Adaptive Large Eddy Simulation (SCALES) is a novel wavelet-based approach that resolves energy containing turbulent motions using wavelet multiresolution decomposition and self-adaptivity. The extraction of the most energetic structures is achieved using wavelet thresholding filter with a priori prescribed threshold level. This strategy, although successful, has a major drawback: the thresholding criterion is global and does not fully utilize the spatial/temporal intermittency of the turbulent flow. In the current numerical effort, for the first time (to the best of our knowledge), the concept of physics-based spatially variable thresholding in the context of wavelet-based numerical techniques for solving PDEs is introduced. The procedure consists of tracking the wavelet thresholding-factor within a Lagrangian frame by exploiting a Lagrangian Path-Line Diffusive Averaging approach that uses linear averaging along characteristics. The results for incompressible flow around NACA 0015 airfoil show a very robust and fast methodology for adjusting the thresholding-factor based on dynamically important flow characteristics, for instance, the magnitude of vorticity or strain rate.

Nejadmalayeri, Alireza; Vasilyev, Oleg V.; Vezolainen, Alexei; de Stefano, Giuliano

2009-11-01

404

Reliability and validity of a brief method to assess nociceptive flexion reflex (NFR) threshold  

PubMed Central

The nociceptive flexion reflex (NFR) is a physiological tool to study spinal nociception. However, NFR assessment can take several minutes and expose participants to repeated suprathreshold stimulations. These 4 studies assessed the reliability and validity of a brief method to assess NFR threshold that uses a single ascending series of stimulations (Peak 1 NFR), by comparing it to a well-validated method that uses 3 ascending/descending staircases of stimulations (Staircase NFR). Correlations between the NFR definitions were high, were on par with test-retest correlations of Staircase NFR, and were not affected by participant sex or chronic pain status. Results also indicated the test-retest reliabilities for the two definitions were similar. Using larger stimulus increments (4-mA) to assess Peak 1 NFR tended to result in higher NFR threshold estimates than using the Staircase NFR definition, whereas smaller stimulus increments (2-mA) tended to result in lower NFR threshold estimates than the Staircase NFR definition. Neither NFR definition was correlated with anxiety, pain catastrophizing, or anxiety sensitivity. In sum, a single ascending series of electrical stimulations results in a reliable and valid estimate of NFR threshold. However, caution may be warranted when comparing NFR thresholds across studies that differ in the ascending stimulus increments. Perspective This brief method to assess NFR threshold is reliable and valid; therefore, it should be useful to clinical pain researchers interested in quickly assessing inter- and intra-individual differences in spinal nociceptive processes.

Rhudy, Jamie L.; France, Christopher R.

2011-01-01

405

Venous leg ulcer pain.  

PubMed

Venous disease and venous leg ulcers are frequently painful. The pain experienced may be constant or intermittent. Constant pain can originate from vascular structures (superficial, deep phlebitis), pitting edema, collagen (lipodermatosclerosis), infection, or scarring (atrophie blanche). Ulcer region pain is often episodic and may be due to surgical or other debridement procedures. Intermittent pain is often related to dressing removal or recent applications of new dressings. An approach to pain control will consider the cause of pain and utilize local measures, regional approaches to edema control, and systemic medication aimed at constant, episodic, or intermittent pain triggers. PMID:12856289

Ryan, Siobhan; Eager, Cathy; Sibbald, R Gary

2003-04-01

406

[The physiology of pain].  

PubMed

This article reviews the basic anatomy and physiology of the normal pain system. During recent years, our knowledge of the pain system has been expanded, with increasing insight into the peripheral and central mechanisms underlying both acute and chronic pain. Several differences in the pain system exist for superficial and deep pain. Descending control mechanisms seem to be important in controlling pain, and neuroplastic changes with central reorganisation are frequently seen in patients suffering from pain. This new knowledge will help in understanding and treating patients with chronic pain syndromes. PMID:16768887

Drewes, Asbjørn Mohr

2006-05-15

407

Orofacial pain: a primer.  

PubMed

Orofacial pain refers to pain associated with the soft and hard tissues of the head, face, and neck. It is a common experience in the population that has profound sociologic effects and impact on quality of life. New scientific evidence is constantly providing insight into the cause and pathophysiology of orofacial pain including temporomandibular disorders, cranial neuralgias, persistent idiopathic facial pains, headache, and dental pain. An evidence-based approach to the management of orofacial pain is imperative for the general clinician. This article reviews the basics of pain epidemiology and neurophysiology and sets the stage for in-depth discussions of various painful conditions of the head and neck. PMID:23809298

De Rossi, Scott S

2013-06-04

408

Associations between autonomic dysfunction and pain in chemotherapy-induced polyneuropathy.  

PubMed

BACKGROUND: Autonomic neuropathy, a relatively common complication of several chemotherapy agents, can affect the vagus nerve and its pain inhibitory capacity, thus increasing sensitivity to pain. This study aimed to evaluate the relationships between autonomic parasympathetic function and the perception of (1) spontaneous pain; (2) experimental non-painful sensations; and (3) experimental painful sensations in chemotherapy-induced neuropathy patients. METHODS: Twenty-seven cancer patients with chemotherapy-induced polyneuropathy were enrolled (20 women, age 56.6?±?7.9). Autonomic parameters of heart rate variability, deep-breathing and Valsalva ratios, experimental non-painful parameters of warm, cold and mechanical detection thresholds, and painful parameters of heat pain thresholds, pain rating of suprathreshold stimulus, mechanical temporal summation and conditioned pain modulation response were examined. RESULTS: Autonomic parameters and spontaneous pain levels were not associated, yet autonomic parameters were positively correlated with non-painful sensations - milder autonomic neuropathy was accompanied by milder sensory neuropathy as indicated by several parameters, e.g., lower Valsalva ratio was correlated with higher warmth detection threshold (r?=?-0.465; p?=?0.033). Autonomic parameters were, however, negatively correlated with painful sensations - lower parasympathetic-vagal activity was associated with higher pain sensitivity as indicated by several parameters, e.g., lower Valsalva ratio was correlated with higher pain rating of suprathreshold stimulus (r?=?-0.559; p?=?0.008). CONCLUSIONS: Diminished vagal function due to neuropathy is associated with, and may possibly underlie, pain disinhibition expressed as greater levels of experimental pain. PMID:23776126

Nahman-Averbuch, H; Granovsky, Y; Sprecher, E; Steiner, M; Tzuk-Shina, T; Pud, D; Yarnitsky, D

2013-06-17

409

Damage tolerance approach  

NASA Astrophysics Data System (ADS)

The philosophy of damage tolerance is illustrated graphically under the subgroups of the objectives and analysis and of damage tolerance and analysis of fracture mechanics. The objectives of damage tolerance are to define relevant service characteristics and determine the characteristics from relevant statistics (standards), to guarantee structural integrity by damage tolerance analysis, and to full scale test the subcomponents. Flow diagrams for propagation analysis and residual strength analysis are included.

Apicella, A.

410

Targinact--opioid pain relief without constipation?  

PubMed

Targinact (Napp Pharmaceuticals Ltd) is a modified-release combination product containing the strong opioid oxycodone plus the opioid antagonist naloxone. It is licensed for "severe pain, which can be adequately managed only with opioid analgesics".1 The summary of product characteristics (SPC) states that "naloxone is added to counteract opioid-induced constipation by blocking the action of oxycodone at opioid receptors locally in the gut". Advertising for the product claims "better pain relief", "superior GI [gastrointestinal] tolerability" and "improved quality of life" "compared to previous treatment in a clinical practice study (n=7836)". Here we consider whether Targinact offers advantages over using strong opioids plus laxatives where required. PMID:21123290

2010-12-01

411

Damage thresholds for terahertz radiation  

NASA Astrophysics Data System (ADS)

Several international organizations establish minimum safety standards to ensure that workers and the general population are protected against adverse health effects associated with electromagnetic radiation. Suitable standards are typically defined using published experimental data. To date, few experimental studies have been conducted at Terahertz (THz) frequencies, and as a result, current THz standards have been defined using extrapolated estimates from neighboring spectral regions. In this study, we used computational modeling and experimental approaches to determine tissue-damage thresholds at THz frequencies. For the computational modeling efforts, we used the Arrhenius damage integral to predict damage-thresholds. We determined thresholds experimentally for both long (minutes) and short (seconds) THz exposures. For the long exposure studies, we used an in-house molecular gas THz laser (?= 1.89 THz, 189.92 mW/cm2, 10 minutes) and excised porcine skin. For the short exposure studies, we used the Free Electron Laser (FEL) at Jefferson Laboratory (?= 0.1-1.0 THz, 2.0-14.0 mW/cm2, 2 seconds) and wet chamois cloths. Thresholds were determined using conventional damage score determination and probit analysis techniques, and tissue temperatures were measured using infrared thermographic techniques. We found that the FEL was ideal for tissue damage studies, while our in-house THz source was not suitable to determine tissue damage thresholds. Using experimental data, the tissue damage threshold (ED50) was determined to be 7.16 W/cm2. This value was in well agreement with that predicted using our computational models. We hope that knowledge of tissue-damage thresholds at THz frequencies helps to ensure the safe use of THz radiation.

Dalzell, Danielle R.; McQuade, Jill; Vincelette, Rebecca; Ibey, Bennet; Payne, Jason; Thomas, Robert; Roach, W. P.; Roth, Caleb L.; Wilmink, Gerald J.

2010-02-01

412

The effects of stimulus location on the gating of touch by heat- and cold-induced pain  

Microsoft Academic Search

The influence of heat- and cold-induced pain on tactile sensitivity, a ª touch gateº , was measured under conditions in which the location of the noxious stimuli was varied with respect to the tactile stimulus applied to the thenar eminence of humans. Vibrotactile thresholds were measured in the absence of pain and during administration of a painful stimulus, with the

LISA M. MAXFIELD; GEORGE A. GESCHEIDER; A. VANIA APKARIAN

2000-01-01

413

Expression of neuron-associated tumor necrosis factor alpha in the brain is increased during persistent pain  

Microsoft Academic Search

Background and Objectives: Evidence implicates the pleiotropic cytokine tumor necrosis factor alpha (TNF?) in the pathogenesis of persistent pain. The present study employs a chronic constriction injury (CCI) model of neuropathic pain to examine TNF? production in the central nervous system (CNS) and in the periphery in this pain model. Methods: CCI-induced hyperalgesia is assessed by measuring the nociceptive threshold

William C. Covey; Tracey A. Ignatowski; Amy E. Renauld; Paul R. Knight; Nader D. Nader; Robert N. Spengler

2002-01-01

414

Zero Tolerance in Schools.  

ERIC Educational Resources Information Center

Questions the effectiveness of the widespread use of zero-tolerance policies enacted by school boards to punish students who violate weapon and drug rules. Suggests that enforcement of zero-tolerance policies has not been equitable. Reviews proposal for alternative to zero tolerance. (PKP)

Henault, Cherry

2001-01-01

415

Evangelicals and Political Tolerance  

Microsoft Academic Search

The article explores four possible explanations for the lower levels of political tolerance of evangelical Christians. First, these differences could be spurious, due to demographic differences. Second, evangelicals may be less tolerant of atheists, homosexuals, and communists, but more tolerant of groups on the other side of the political spectrum, suggesting a group effect. Third, evangelical intolerance may be the

Clyde Wilcox; Ted Jelen

1990-01-01

416

[Central pain processing and Parkinson's disease. Epidemiology, physiology, and experimental results issuing pain processing].  

PubMed

Parkinson's disease (PD) is caused by degeneration of the dopaminergic neurons in the substantia nigra (SN) and a resulting dysfunction of the nigrostriatal pathways including the basal ganglia. Beside motor symptoms, different types of pain (e.g., dystonic musculoskeletal pain or central pain) occur in a considerable number of patients. In addition, abnormalities in pain processing have been observed in PD patients, which may present as increased pain sensitivity. The pathophysiological mechanisms involved in disturbed pain<