Pain
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Previous studies have shown that transection of the sciatic nerve induces dramatic changes in sodium currents of axotomized dorsal root ganglion (DRG) neurons, which are paralleled by significant changes in the levels of transcripts of several sodium channels expressed in these neurons. Sodium currents that are resistant to tetrodotoxin (TTX-R) and the transcripts of two TTX-R sodium channels are significantly attenuated, while a rapidly repriming tetrodotoxin-sensitive (TTX-S) current emerges and the transcripts of alpha-III sodium channel, which produce a TTX-S current when expressed in oocytes, are up-regulated. ⋯ Transcripts of NaN and SNS, two sensory neuron-specific TTX-R sodium channels, are significantly down-regulated as is the TTX-R sodium current, while transcripts of the TTX-S alpha-III sodium channel and a rapidly repriming TTX-S Na current are up-regulated in small diameter DRG neurons. These changes may provide at least a partial basis for the hyperexcitablity of DRG neurons that contributes to hyperalgesia in this model.
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A water-soluble three-layered oral mucosa-adhesive film made from hydroxypropyl cellulose containing dibucaine (0.25 mg of drug/cm(2)) was designed for alleviation of severe pain due to oral ulcers, caused by chemotherapy and/or radiotherapy. We report two patients with constant severe pain ulcers treated with the dibucaine film. Patients were asked to record the time that pain was relieved while chewing following first application of the film. Pain relief lasted for 2-5 h after application of the dibucaine film.
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Randomized Controlled Trial Clinical Trial
Suckling- and sucrose-induced analgesia in human newborns.
This experiment had three goals: 1. To identify the basis of sucking-induced analgesia in healthy, term, newborn humans undergoing the painful, routine, procedure of heel lance and blood collection. 2. To evaluate how taste-induced and sucking-induced analgesias combine to combat pain. 3. ⋯ Sucking an unflavored pacifier was analgesic when and only when suck rate exceeded 30 sucks/min. 2. The combination of sucrose and nonnutritive sucking was remarkably analgesic; we saw no behavioral indication in nine of the ten infants that the heel lance had even occurred. 3. Grimacing was reduced to almost naught by procedures that essentially eliminated crying and markedly reduced heart rate during the blood harvesting procedure.
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In this study, pain perception, somatosensory event-related potential (SERP) and skin conductance response (SCR) changes during hypnotic suggestions of Deep Relaxation, Dissociated Imagery, Focused Analgesia, and Placebo, compared with a Waking baseline condition, were investigated. SERPs were recorded from frontal, temporal, central, and parietal scalp sites. Ten high, 9 mid, and 10 low hypnotizable right-handed women participated in the experiment. ⋯ These subjects also showed faster habituation of SCRs when compared with mid and low hypnotizables. During Dissociated Imagery and Focused Analgesia, highly hypnotizable subjects also disclosed a smaller total number of evoked SCRs than did mid and low hypnotizable subjects. The results are discussed considering possible common and different mechanisms to account for the effects of different hypnotic suggestions.
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Pain intensity ratings of 'usual' pain, or pain 'on average', are gaining in popularity since they are arguably a more realistic measure of a patient's pain status than the single snapshot of 'current' pain. An alternative to the 'actual average' of ratings obtained from multiple measures is the single rating of patients' recall of their 'usual' pain over a period of time, usually 1 week. The use of such a scale relies on the assumption that patients can accurately recall their 'usual' pain. ⋯ Using the Intra-class Correlation Coefficient (ICC) to compute accuracy, the single rating asking patients to estimate their pain 'on average' over the week was found to be an accurate measure of 'actual average' pain intensity (ICC=0.82) and more accurate than 'current' pain (ICC=0.66). Although some composite measures of single ratings gave more accurate estimates of 'actual average' pain, this was not considered sufficient advantage to advocate their use. The results of this study propose the single rating of pain 'on average' as a valid and practical measure of a patient's pain intensity over a period of 1 week.