Japanese cross-cultural validation study of the Pain Stage of Change Questionnaire.

INTRODUCTION: Although evidence supports efficacy of treatments that enhance self-management of chronic pain, the efficacy of these treatments has been hypothesized to be influenced by patient readiness for self-management. The Pain Stage of Change Questionnaire (PSOCQ) is a reliable and valid measure of patient readiness to self-manage pain. However, there is not yet a Japanese version of the PSOCQ (PSOCQ-J), which limits our ability to evaluate the role of readiness for pain self-management in function and treatment response in Japanese patients with chronic pain. OBJECTIVE: Here, we sought to develop the PSOCQ-J and evaluate its psychometric properties. METHODS: We recruited 201 patients with chronic pain. The study participants were asked to complete the PSOCQ-J and other measures assessing pain severity, pain interference, catastrophizing, self-efficacy, and pain coping strategies. RESULTS: The results supported a 4-factor structure of the PSOCQ-J. We also found good to excellent internal consistencies and good test-retest reliabilities for the 4 scales. The Precontemplation scale had weak to moderate positive correlations with measures of pain-related dysfunction and maladaptive coping. The Action and Maintenance scales had weak to moderate positive correlations with measures of self-efficacy and adaptive coping. The Contemplation scale had weak positive correlations with measures of pain interference and both adaptive and maladaptive coping. CONCLUSIONS: The PSOCQ-J demonstrated adequate psychometric properties in a sample of Japanese patients with chronic pain. This measure can be used to evaluate the role that readiness to self-manage pain may play in adjustment to chronic pain in Japanese pain populations.

Development of comprehensive diagnostic criteria for complex regional pain syndrome in the Japanese population.

Complex regional pain syndrome (CRPS) is a syndrome that describes a broad spectrum of sensory, motor and autonomic-like features with unproven etiology. The International Association for the Study of Pain (IASP) diagnostic criteria of CRPS shows high sensitivity but poor specificity. Using statistical-pattern-recognition methods, American researchers have suggested a new set of criteria offering acceptable sensitivity and high specificity. However, non-American CRPS patients present distinct subsets of CRPS-related signs/symptoms from those of American patients. Here, we followed a series of American studies to develop a set of CRPS diagnostic criteria that would be most suitable for the Japanese population. A standardized sign/symptom checklist was used in patient evaluations to obtain data on CRPS-related signs/symptoms in 195 participants meeting the IASP criteria. Using factor analysis, we grouped CRPS-related signs/symptoms into five distinct subgroups (trophic change, motor dysfunction, abnormal pain processing, asymmetric sudomotor activity and asymmetric edema). Discriminant function analysis of these subgroups, regarding their ability to discriminate between CRPS and non-CRPS etiology, indicated that modifying the IASP criteria could increase clinical diagnostic accuracy in the Japanese population. Our diagnostic criteria are not exactly the same as the American criteria, indicating a need for more regionally based CRPS diagnostic criteria. Different sets of CRPS diagnostic criteria could lead to dissimilar patients being diagnosed as CRPS, however, presenting problems for translation of therapeutic effects found in various studies. Therefore, we further recognize a need for a global set of common CRPS diagnostic criteria.

Experimental neuropathy in mice is associated with delayed behavioral changes related to anxiety and depression.

BACKGROUND: Patients with chronic pain frequently suffer affective disorders, particularly anxiety and depression. Although clinical research on the relationship between pain and depressive symptoms has been done, it is not clear whether pain causes depression or depression exaggerates pain. To investigate the relation between pain and affect, we measured anxiety and depression-related behaviors in mice after spinal nerve ligation using classical behavioral tests. METHODS: After unilateral ligation of the left fifth lumbar nerve, we measured pain behaviors using von Frey and radiant heat tests. Activity level, anxiety-related behaviors, and depression-related behaviors were tested with open field, light-dark exploration, elevated plus-maze, and forced swim tests. RESULTS: Sensory hypersensitivity was observed within a few days after ligation. Anxiety and depression-related behaviors were not seen 2 and 7 days after ligation. However, 15 and 30 days after ligation we found clear evidence of anxiety and depression-related behaviors, without loss of mobility. CONCLUSIONS: Nerve injury can trigger affective disturbances in mice that appear much later than sensory hypersensitivity.

Long-lasting effect of transcutaneous electrical nerve stimulation on the thermal hyperalgesia in the rat model of peripheral neuropathy.

We demonstrate here unexpectedly long-lasting effect of transcutaneous electrical nerve stimulation (TENS) to alleviate thermal hyperalgesia in rats with peripheral neuropathy produced by constriction of sciatic nerve. For TENS groups, electrical stimulation for 16.7 min (1 Hz, paired current, 12 mA, 5-ms interval, 0.2-ms duration, 999 pairs), once a day, was delivered for 5 consecutive days, under halothane anesthesia (Hal-TENS group) or pentobarbital anesthesia (Pent-TENS group). For non-TENS groups, only the anesthesia was delivered (Hal-no TENS group, Pent-no TENS group). For the control group, neither anesthetics nor TENS was delivered. To evaluate hyperalgesia, paw withdrawal latency (PWL) to radiant heat was measured before nerve constriction and five times after the constriction; just before TENS and at 1, 3, 7, and 14 days after the completion of TENS. Compared to the non-TENS groups, rats in the TENS groups showed significantly reduced thermal hyperalgesia at least for 3 days (Pent-TENS group) or for 7 days (Hal-TENS group) after TENS. These results indicate a possible long-lasting therapeutic effect of TENS applied under general anesthesia.

HIV mucosal vaccine: nasal immunization with gp160-encapsulated hemagglutinating virus of Japan-liposome induces antigen-specific CTLs and neutralizing antibody responses.

Nasal immunization of normal mice with HIVgp160-encapsulated hemagglutinating virus of Japan (HVJ)-liposome induced high titers of gp160-specific neutralizing IgG in serum and IgA in nasal wash, saliva, fecal extract, and vaginal wash, along with both Th1- and Th2-type responses. HIVgp160-specific IgG- and IgA-producing cells were also detected in mononuclear cells isolated from spleen, nasal cavity, salivary gland, intestinal lamina propria, and vaginal tissue of nasally immunized mice. In addition, CD8(+) CTLs were induced in mice nasally immunized with gp160-HVJ-liposome. These findings suggest that two layers of effective HIV-specific humoral and cellular immunity, in mucosal and systemic sites, were induced by this nasal vaccine. In immunodeficient mice, nasal immunization with gp160-HVJ-liposome induced Ag-specific immune responses for the systemic and mucosal compartments of both Th1 (IFN-gamma(-/-)) and Th2 (IL-4(-/-)). In vitro Ag-specific serum IgG Ab and vaginal wash samples possessing IgA and IgG Abs that had been induced by nasal immunization with gp160-HVJ-liposome were able to neutralize a clinically isolated strain of HIV-MN strain isolated from Japanese hemophiliac patients. Taken together, these results suggest that, for the prevention and control of AIDS, nasally administered gp160-HVJ-liposome is a powerful immunization tool that induces necessary Ag-specific immune responses at different stages of HIV infection.

[A case of shoulder pain following right basilic vein catheterization].

We have experienced a case of total laryngectomy with graft of the rectus abdominis muscle skin flap because of the recurrent lingual cancer. Just before the operation, we used right basilic vein for introduction of a central venous catheter. Right shoulder pain occurred on the first postoperative day. After the operation, we found that the catheter from the right basilic vein was inserted to the right jugular vein. We pulled out it and inserted another catheter from the left subclavian vein. Shoulder pain diminished and then pyrexia and symptom of infection diminished. After recatheterization, shoulder pain was suspected to be the result of frozen shoulder. We should be aware that shoulder pain could occur by immobility of upper extremities when basilic venous catheter is in place.