Strategies in pain management: new and potential indications for COX-2 specific inhibitors

Repurposing of Bryophyllum pinnatum for dysmenorrhea treatment: a systematic scoping review and case series

Dysmenorrhea affects women throughout their reproductive years but there has been a lack of effective and well-tolerated treatment options. Pain symptoms mainly result from inflammatory processes and increased contractile activity in the myometrium. The reported use of Bryophyllum pinnatum preparations against inflammation and pain in ethnomedicine as well as current pharmacological data on their inhibition of myometrial contractility led us to hypothesize that this medicinal plant might be a new treatment option for dysmenorrhea. In the first part of the present work, clinical, in vivo, and in vitro studies on the anti-nociceptive and anti-inflammatory, as well as on myometrium relaxing properties of B. pinnatum are reviewed. In the second part, cases of five women with dysmenorrhea who were tentatively treated with a B. pinnatum product are described. The review revealed thirty-three experimental in vivo and in vitro studies, but no clinical study, reporting anti-nociceptive and anti-inflammatory effects of B. pinnatum extracts and compounds in a wide range of conditions. Moreover, sixteen publications on smooth muscle contractility revealed relaxing effects. The latter consisted of clinical evidence, as well as of in vivo and in vitro data. The evidence reviewed therefore provided a rational basis for the use of B. pinnatum in the treatment of dysmenorrhea. We subsequently set out to tentatively treat patients with a well-tolerated B. pinnatum product that is registered (without indication) and commonly used in obstetrics and gynecology in Switzerland. All five treated patients reported a reduction in pain symptoms and 4 out of 5 indicated a reduced intake of painkillers during menstruation. Taken together, the reviewed information on the pharmacological properties and clinical evidence of B. pinnatum extracts and compounds as well as the outcomes of all five patients in the case series support our hypothesis in favor of B. pinnatum as a new, well-tolerated therapeutic approach for dysmenorrhea. Prospective clinical studies are urgently needed.

Assessment of prevalence, knowledge and health-related practices of dysmenorrhea among Malaysian women in Kuala Lumpur: a cross-sectional survey

BACKGROUND

Menstruation is a natural phenomenon considered an important indicator of women's health, reflecting their endocrine function. Women in low middle income countries face substantial menstrual hygiene management challenges. Data on the knowledge of dysmenorrhea and health-related practices among Malaysian women are scarce. The present study aimed to investigate the prevalence of dysmenorrhea among Malaysian women in Kuala Lumpur and its association with socio-demographic factors, knowledge level, and general practices.

METHOD

A cross-sectional study was carried out among Malaysian women in Kuala Lumpur. A total of 362 unmarried women, nulliparous and aged between 18 and 25 years old, were included in this study. Participants were conveniently recruited through online platforms as well as face to face using a self-administered questionnaire with five sections consisting of demographics, menstrual characteristics, Working ability, Location, Intensity, Days of pain, Dysmenorrhea (WaLIDD) score for diagnosing and assessing the severity of dysmenorrhea as well as an evaluation of respondents' general knowledge and practices towards dysmenorrhea. The collected data were analysed using the SPSS tool, a descriptive statistic was used to report demographic characteristics. Inferential statistics was used to report the differentiation, association, and correlations of the variables.

RESULTS

The prevalence of primary dysmenorrhea was 73.2%. It was found that the majority of the respondents had poor knowledge (60%) and poor practices (61.88%) of dysmenorrhea. The most common preventive practices among the respondents were using dietary supplements, and herbs, taking a rest and exercising. The findings also indicated that dysmenorrhea among the respondents was significantly associated with family history of dysmenorrhea (p = 0.002), monthly income (p = 0.001), and knowledge level (p = 0.001).

CONCLUSION

Dysmenorrhea has a high prevalence among women in Malaysia in Kula Lumpur driven by low knowledge and lack of evidence-based practices among these women. Thus, it is critical for Government and healthcare authorities to promote education related to women health among Malaysian women.

Potential metabolites of Arecaceae family for the natural anti-osteoarthritis medicine: A review

Osteoarthritis (OA) is a chronic inflammatory disorder of the joints caused by fluid and cartilage matrix component reduction. This disease results in symptoms of pain, deformity, and limitation of movement. In general, OA is treated with anti-inflammatory drugs and chondroprotection compounds, includes natural nutraceutical ingredients, which are expected to be effective and have minimal side effects. Arecaceae plants are widely spread worldwide, especially in tropical areas. The objective of this review is to collect information about the Arecaceae family as anti-OA agents, with the main study focusing on the primary and secondary metabolites of plants of the Arecaceae family, i.e., sugar palm (Arenga pinnata), nipa palm (Nypa fruticans), palmyra palm (Borassus flabellifer), date palm (Phoenix dactylifera), and betel nut (Areca catechu) have potential as anti-OA agents. The Arecaceae's metabolites that show anti-inflammatory and chondroprotective effects are galactomannan, fatty acids (linoleic and linolenic acids), flavonoids (quercetin, luteolin, isorhamnetin), phenolics (coumaric acid, ferulic acid), polyphenols (epicatechin), and steroids (stigmasterol, campesterol, spirostane). Based on the reports, the Arecaceae family plants become worthy of being explored and developed into natural anti-OA products, such as supplements or nutraceuticals.

Revealing the mechanism of raw and vinegar-processed Curcuma aromatica Salisb. [Zingiberaceae] regulates primary dysmenorrhea in rats via integrated metabolomics

Primary dysmenorrhea (PDM) is a common disorder among women around the world. Two processed products of Curcuma aromatica Salisb. [Zingiberaceae] (CAS) are traditional Chinese medicine (TCM) that have long been used to treat gynecological blood stasis syndrome such as primary dysmenorrhea. The mechanisms and active substances of CAS are still largely unknown. The study aimed to establish a rat model of primary dysmenorrhea which investigates the differences between the pharmacodynamics and mechanisms of raw CAS (RCAS) and vinegar-processed CAS (VCAS). Histopathology, cytokinetics, and metabolomics were adopted to evaluate the anti-blood stasis effect of RCAS and VCAS. In metabolomics, endogenous differential metabolites in plasma, urine, and feces are the essential steps to evaluate the effect of RCAS and VCAS. In this study, the rat model of primary dysmenorrhea was successfully established. After RCAS and VCAS intervention, the uterine tissue morphology of dysmenorrhea model rats was improved, and gland hypertrophy and myometrial hyperplasia were reduced as well as neutrophil content. Compared with the RCAS group, the VCAS group had better uterine morphology, few inflammatory factors, and significantly improved amino acid and lipid metabolism. The aforementioned results support the conclusion that VCAS performed better than RCAS in primary dysmenorrhea and that vinegar processing increases the efficacy of CAS.

Does Dysmenorrhea Affect Clinical Features and Long-Term Surgical Outcomes of Patients With Ovarian Endometriosis? A 12-Year Retrospective Observational Cohort Study

Background

To examine and compare the differences in clinical characteristics and long-term postoperative outcomes of ovarian endometriomas (OMA) patients with and without dysmenorrhea, including data from at least 8 years of postoperative follow-up examinations.

Methods

Retrospective analysis of 334 OMA patients, including their demographic and clinical data. Long-term follow-up record was also collected. All laparoscopic cystectomy procedures were performed by the same surgeon at Peking Union Medical College Hospital between January 2009 and April 2013. Patients were divided into the dysmenorrhea and non-dysmenorrhea groups to perform the analysis of their preoperative characteristics, relevant surgical findings, and postoperative outcomes at the follow-up.

Results

Out of 334 OMA patients, 257 (76.9%) patients were allocated to the dysmenorrhea group, while the rest 77 (23.1%) patients were included in the non-dysmenorrhea group. Compared with the dysmenorrhea group, the non-dysmenorrhea group exhibited a reduced proportion of chronic pelvic pain (CPP) (P = 0.003), dyspareunia (P < 0.001), tenesmus (P < 0.001), concurrency of deep infiltrating endometriosis (DIE) (P < 0.001), and adenomyosis (P = 0.032). Preoperative infertility was significantly higher in the dysmenorrhea group (P = 0.001). The mean operating time in the dysmenorrhea vs. the non-dysmenorrhea group was 68.0 vs. 56.0 min (P < 0.001). According to the revised American Fertility Society (rAFS) scoring system, the mean scores of the two groups were 52.1 vs. 44.6 (P = 0.033). During follow-up, the dysmenorrhea group showed a higher rate of disease relapse (P < 0.001). A minimum postoperative follow-up period of 8 years was required to evaluate the pregnancy outcomes. Successful pregnancies were identified in 97/257 (37.7%) cases in the dysmenorrhea group and 36/77(46.8%) cases in the non-dysmenorrhea group (P = 0.157), respectively. Though the dysmenorrhea group had a higher rate of postoperative infertility, differences were not significant between the two groups.

Conclusions

Compared with the dysmenorrhea group, OMA patients without dysmenorrhea exhibited lower proportions of CPP, dyspareunia, tenesmus, lower concurrency of DIE and adenomyosis, shorter mean operating time, lower mean rAFS scores, and lower infertility rates. During the long-term follow-up, a lower recurrence rate was observed in the non-dysmenorrhea group. Regarding fertility outcomes, non-dysmenorrhea patients had a higher likelihood of successful pregnancy after surgery. Postoperative management needs to be evaluated separately according to dysmenorrhea pathology.

The Prevalence, Management and Impact of Dysmenorrhea on Medical Students' Lives-A Multicenter Study

Introduction: Dysmenorrhea is defined as the presence of painful menstruation, and it affects daily activities in different ways. The aims of this study were to assess the prevalence and management of dysmenorrhea and to determine the impact of dysmenorrhea on the quality of life of medical students. Material and methods: The study conducted was prospective, analytical and observational and was performed between 7 November 2019 and 30 January 2020 in five university centers from Romania. The data was collected using an original questionnaire regarding menstrual cycles and dysmenorrhea. The information about relationships with family or friends, couples’ relationships and university activity helped to assess the effects of dysmenorrhea on quality of life. The level of significance was set at p < 0.05. Results: The study comprised 1720 students in total. The prevalence of dysmenorrhea was 78.4%. During their menstrual period, most female students felt more agitated or nervous (72.7%), more tired (66.9%), as if they had less energy for daily activities (75.9%) and highly stressed (57.9%), with a normal diet being difficult to achieve (30.0%). University courses (49.4%), social life (34.5%), couples’ relationships (29.6%), as well as relationships with family (21.4%) and friends (15.4%) were also affected, depending on the duration and intensity of the pain. Conclusion: Dysmenorrhea has a high prevalence among medical students and could affect the quality of life of students in several ways. During their menstrual period, most female students feel as if they have less energy for daily activities and exhibit a higher level of stress. The intensity of the symptoms varies considerably and, with it, the degree of discomfort it creates. Most student use both pharmacological and non-pharmacological methods to reduce pain (75.7%). University courses, social life, couples’ relationships, as well as relationships with family and friends are affected, depending on the duration and intensity of the pain.

Prediction of Mefenamic Acid Crystal Shape by Random Forest Classification

OBJECTIVE

Particle shape can have a significant impact on the bulk properties of materials. This study describes the development and application of machine-learning models to predict the crystal shape of mefenamic acid recrystallized from organic solvents.

METHODS

Crystals were grown in 30 different solvents to establish a dataset comprising solvent molecular descriptors, process conditions and crystal shape. Random forest classification models were trained on this data and assessed for prediction accuracy.

RESULTS

The highest prediction accuracy of crystal shape was 93.5% assessed by fourfold cross-validation. When solvents were sequentially excluded from the training data, 32 out of 84 models predicted the shape of mefenamic acid crystals for the excluded solvent with 100% accuracy and a further 21 models had prediction accuracies from 50-100%. Reducing the feature set to only solvent physical property descriptors and supersaturations resulted in higher overall prediction accuracies than the models trained using all available or another selected subset of molecular descriptors. For the 8 solvents on which the models performed poorly (< 50% accuracy), further characterisation of crystals grown in these solvents resulted in the discovery of a new mefenamic acid solvate whereas all other crystals were the previously known form I.

CONCLUSIONS

Random forest classification models using solvent physical property descriptors can reliably predict crystal morphologies for mefenamic acid crystals grown in 20 out of the 28 solvents included in this work. Poor prediction accuracies for the remaining 8 solvents indicate that further factors will be required in the feature set to provide a more generalized predictive morphology model.

Why It Is Important to Consider the Effects of Analgesics on Sleep: A Critical Review

We review the known physiological mechanisms underpinning all of pain processing, sleep regulation, and pharmacology of analgesics prescribed for chronic pain. In particular, we describe how commonly prescribed analgesics act in sleep-wake neural pathways, with potential unintended impact on sleep and/or wake function. Sleep disruption, whether pain- or drug-induced, negatively impacts quality of life, mental and physical health. In the context of chronic pain, poor sleep quality heightens pain sensitivity and may affect analgesic function, potentially resulting in further analgesic need. Clinicians already have to consider factors including efficacy, abuse potential, and likely side effects when making analgesic prescribing choices. We propose that analgesic-related sleep disruption should also be considered. The neurochemical mechanisms underlying the reciprocal relationship between pain and sleep are poorly understood, and studies investigating sleep in those with specific chronic pain conditions (including those with comorbidities) are lacking. We emphasize the importance of further work to clarify the effects (intended and unintended) of each analgesic class to inform personalized treatment decisions in patients with chronic pain. © 2021 American Physiological Society. Compr Physiol 11:1-31, 2021.

Regulation of Mild Moxibustion on Uterine Vascular and Prostaglandin Contents in Primary Dysmenorrhea Rat Model

Objective

Primary dysmenorrhea (PD) is a common and high incidence disease in gynecology, which seriously affects the quality of life in young women. Our previous study found that mild moxibustion could treat abdominal pain of PD patients, but the mechanism is still unclear. Therefore, this study aims to partly investigate the treatment mechanism of moxibustion for PD, especially on uterine microcirculation.

Methods

Forty 3-month-old Sprague Dawley female rats were randomly divided into four groups, including group A (saline control group, n = 10), group B (control plus moxibustion group, n = 10), group C (PD model group, n = 10), group D (PD. model plus moxibustion group, n = 10). The PD rat model was established by injecting estradiol benzoate and oxytocin. Mild moxibustion on Sanyinjiao (SP6) and Guanyuan (CV4) acupoints was once a day, 20 minutes per time, for 10 consecutive days. A vaginal smear was used to test the estrous cycle of rats. Uterine microvascular thickness was observed by stereomicroscope. And we detected the content of prostaglandin F_2α (PGF_2α ) and prostaglandin E₂ (PGE₂) in uterine tissue by enzyme-linked immunosorbent assay.

Results

Mild moxibustion can enlarge the microvessels, improve the microcirculation disturbance, and relieve the swelling of the uterus in PD rats. During the mild moxibustion intervention, the contents of PGF_2α and PGE₂ in uterus issues were synchronous increases or decreases and the changes of PGE₂ were more obvious, but the changes of uterine microvasculature and morphology caused by the decrease of PGF_2α were greater than PGE₂.

Conclusion

Mild moxibustion at SP6 and CV4 acupoints may relax uterine microvascular obstacle by reducing the content of PGF_2α in uterine tissue, improve the microcirculation disorder, and then alleviate the PD rat's uterine swelling.

Increased Incidence of Dysmenorrhea in Women Exposed to Higher Concentrations of NO, NO2, NOx, CO, and PM2.5: A Nationwide Population-Based Study

Background: Air pollution is speculated to affect the reproductive health of women. However, a longitudinal association between exposure to air pollution and dysmenorrhea has not been identified, which this study aimed to examine this point.

Methods: Two nationwide databases, namely the Taiwan Air Quality Monitoring database and the Taiwan National Health Research Institutes database were linked. Women with a history of dysmenorrhea (International Classification of Disease, Ninth Revision, Clinical Modification code 625.3) before 2000 were excluded. All participants were followed from January 1, 2000 until the diagnosis of dysmenorrhea, withdrawal from National Health Insurance, or December 31, 2013. Furthermore, air pollutants were categorized into quartiles with three cut-off points (25th, 50th, and 75th percentiles). The Cox regression model was used to calculate the hazard ratios of dysmenorrhea.

Results: This study enrolled 296,078 women. The mean concentrations of yearly air pollutants were 28.2 (±12.6) ppb for nitric oxides (NO_x), 8.91 (±7.93) ppb for nitric oxide (NO), 19.3 (±5.49) ppb for nitrogen dioxide (NO₂), 0.54 (±0.18) ppm for carbon monoxide (CO), and 31.8 (±6.80) μg/m³ for PM_2.5. In total, 12,514 individuals developed dysmenorrhea during the 12-year follow-up. Relative to women exposed to Q1 concentrations of NO_x, women exposed to Q4 concentrations exhibited a significantly higher dysmenorrhea risk [adjusted hazard ratio (aHR)= 27.9, 95% confidence interval (CI) = 21.6–31.3]; similarly higher risk was found for exposure to NO (aHR = 16.7, 95% CI = 15.4–18.4) and NO₂ (aHR = 33.1, 95% CI = 30.9–37.4). For CO, the relative dysmenorrhea risk in women with Q4 level exposure was 28.7 (95% CI = 25.4–33.6). For PM_2.5, women at the Q4 exposure level were 27.6 times (95% CI = 23.1–29.1) more likely to develop dysmenorrhea than those at the Q1 exposure level.

Conclusion: Our results showed that women would have higher dysmenorrhea incidences while exposure to high concentrations of NO, NO₂, NO_x, CO, and PM_2.5.

Immediate Analgesic Effect of Acupuncture in Patients With Primary Dysmenorrhea: A fMRI Study

Primary dysmenorrhea (PDM) is a common gynecological disease characterized by lower abdominal pain. Acupuncture is considered a good alternative therapy for PDM. However, the central mechanism of the analgesic effect of acupuncture is largely unknown. In this study, eligible patients were randomized into the real and sham acupuncture groups using a computer-generated, permuted block randomization method. The study cohort comprised 34 patients: 19 in the real acupuncture group and 15 in the sham acupuncture group. The clinical characteristics of the patients during their menstrual period were collected, and imaging scans were performed during the first 3 days of the patients' menstrual period. We analyzed task and resting functional magnetic resonance imaging (fMRI) data to investigate the potential central mechanism of the immediate effect of acupuncture intervention on the intensity of PDM pain. The task fMRI study found that the rostral anterior cingulate cortex (rACC) and right supplemental motor area were activated during real acupuncture. Using the resting-state functional connectivity (FC) method, we found a post- versus pre-treatment change in the FC of the rACC and left precentral gyrus in the comparison of real acupuncture versus sham acupuncture. In addition, the FC of the rACC-left precentral gyrus at baseline was negatively correlated with short-term analgesia, while the change in the FC of the rACC-left precentral gyrus was positively correlated with short-term analgesia after acupuncture treatment. These findings support the importance of rACC-left precentral gyrus resting-state FC in the modulation of the intensity of PDM pain through acupuncture, which may shed light on the central mechanism of acupuncture in the treatment of PDM.

Is primary dysmenorrhea a precursor of future endometriosis development?

Primary dysmenorrhea (PD) is the most common gynecologic disorder during adolescence and it is characterized by crampy lower abdominal pain that occurs during menstruation. Secondary dysmenorrhea, in contrast, has the same clinical features but occurs in women with a disease that could account for their symptoms (endometriosis, adenomyosis, uterine fibroids, pelvic inflammatory disease). Endometriosis is the most common cause of secondary dysmenorrhea and it should be considered in patients with persistent and clinically significant dysmenorrhea despite treatment. It is often diagnosed after a long delay, increasing the likelihood of pain chronicity and fertility problems at a later age. Women who suffer from dysmenorrhea in adolescence have higher risk of endometriosis in future. The open question is if endometriosis was already present at the onset of dysmenorrhea but undiagnosed or if PD favors subsequent development of endometriosis-associated pain. Since PD is associated with higher risk for developing chronic pain state and shares some of the same pain pathways of endometriosis (prostaglandins overproduction, inflammation, peripheral sensitization, central sensitization and abnormal stress responses), a correlation between PD and endometriosis is suggested. To know whether it is a risk factor for the development of endometriosis-associated pain may provide an opportunity for early intervention and prevention. The present review aims to investigate the clinical and pathogenetic features of PD and endometriosis in order to identify a possible association between the two conditions.

Efficacy of herbal medicine (cinnamon/fennel/ginger) for primary dysmenorrhea: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To assess the efficacy of herbal medicine (cinnamon/fennel/ginger) for treating primary dysmenorrhea.

METHODS

Relevant studies were searched in multiple databases. The weighted mean difference (WMD) was used as the effect indicator for measurement data, and each effect size was given estimates and 95% confidence intervals (CIs).

RESULTS

Nine studies with 647 patients were selected. Compared with the results in the control group, pain intensity was significantly relieved in the trial group when assessed by the intervention (cinnamon vs. placebo: WMD = 1.815, 95% CI = 1.330-2.301; fennel vs. placebo: WMD = 0.528, 95% CI = 0.119-6.829; ginger vs. placebo: WMD = 2.902, 95% CI = 2.039-3.765), observation period (one cycle: WMD = 2.061, 95% CI = 0.815-3.307; one cycles: WMD = 1.831, 95% CI = 0.973-2.690), and study quality (high quality: WMD = 2.224, 95% CI = 1.488-2.960). Pain duration was significantly shorter in the trial group (cinnamon vs. placebo: WMD = 16.200, 95% CI = 15.271-17.129). No publication bias was observed for either outcome.

CONCLUSIONS

For primary dysmenorrhea, cinnamon/fennel/ginger effectively reduced pain intensity, and cinnamon shortened the duration of pain. Further studies are needed to confirm our results.

Prevalence and Risk Factors Associated with Primary Dysmenorrhea among Chinese Female University Students: A Cross-sectional Study

STUDY OBJECTIVE

To examine prevalence and risk factors associated with primary dysmenorrhea among Chinese female university students in Hunan province, China.

DESIGN

A cross-sectional study.

SETTING

Female university students in Changsha city, Hunan province, China.

PARTICIPANTS

Four thousand six hundred six female individuals selected using a multistage cluster random sampling method.

INTERVENTIONS

A self-administered questionnaire, which included sociodemographic information, lifestyle habits, emotional characteristics, and menstruation pattern, was used to collect data.

MAIN OUTCOME MEASURES

Information about menarche, body mass index, cycle length and regularity, primary dysmenorrhea, physical exercise, depression, and anxiety.

RESULTS

The prevalence of primary dysmenorrhea was 41.7% (1921/4606) among Chinese female university students. Multivariate binary logistic regression indicated that being a minority (odds ratio [OR], 1.335; 95% confidence interval [CI], 1.083-1.646), underweight (OR, 1.249; 95% CI, 1.08-1.42), annual household income less than 80,000 CNY (OR, 1.169; 95% CI, 1.018-1.342), maternal history of dysmenorrhea (OR, 2.553; 95% CI, 2.236-2.915), age at menarche younger than 12 years (OR, 1.161; 95% CI, 1.013-1.329), irregular menstrual cycle (OR, 1.216; 95% CI, 1.063-1.391), and skipping breakfast (OR, 1.294; 95% CI, 1.124-1.490) were associated risk factors of primary dysmenorrhea.

CONCLUSION

The prevalence of primary dysmenorrhea among Chinese university students is relatively high. Various risk factors were identified that associated with primary dysmenorrhea. More effort and attention should therefore be directed toward this health problem in China.

Pelvic floor dysfunctions in female cheerleaders: a cross-sectional study

INTRODUCTION AND HYPOTHESIS

Cheerleaders perform high-impact maneuvers that can be associated with pelvic floor dysfunction. We hypothesized that female cheerleaders would report more symptoms of pelvic floor dysfunction and fewer symptoms of premenstrual syndrome than nonathletic women.

METHODS

This cross-sectional study included high-performance female cheerleaders and young nonathletic, nulliparous, and normal-weight females. Demographics, sports practices, and pelvic floor dysfunction data were collected through an electronic questionnaire. Urinary symptoms were collected through the International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF) and King's Health Questionnaire. Intestinal symptoms were collected through the use of Criterion F of item C3, referring to functional constipation of Rome III and Fecal Incontinence Severity Index. Data on sexual function were collected through the Female Sexual Function Index. Data on pelvic organ prolapse were obtained through the International Consultation on Incontinence Questionnaire-Vaginal Symptoms (ICIQ-VS). In addition, questions about premenstrual syndrome-dysmenorrhea, irritability, headache, tiredness, fluid retention, and constipation-were collected through the Menstrual Symptom Questionnaire. The comparison between groups of the quantitative variables was performed using the Mann-Whitney U test. Odds ratios (OR) and 95% confidence intervals (CI) were estimated for comparison between groups on the occurrence of pelvic floor muscle dysfunction symptoms. A significance level of 5% was adopted.

RESULTS

A total of 156 women (78 cheerleaders and 76 nonathletes) completed the electronic questionnaire. Anal incontinence was the most prevalent symptom of pelvic floor muscle dysfunction. Cheerleaders were 2.3 times more likely to report symptoms regarding anal incontinence than nonathletic women. For the other symptoms of pelvic floor dysfunction, no statistical differences between the groups were found. Cheerleaders reported fewer symptoms of tiredness and constipation during the premenstrual period than did nonathletic women.

CONCLUSION

Pelvic floor dysfunction, particularly anal incontinence, appears to be more prevalent among cheerleaders than among nonathletic women. In addition, cheerleaders demonstrated fewer symptoms of tiredness and constipation during the premenstrual period.

Acupoint herbal plaster for patients with primary dysmenorrhea: study protocol for a randomized controlled trial

BACKGROUND

Primary dysmenorrhea (PD), is one of main gynecological complaints in women of child-bearing age. Common medications for PD do not always achieve satisfactory outcome of pain relief. Hence, both health professionals and patients are seeking help from complementary and alternative medicine. The acupoint herbal plaster (AHP), which appears to be a safe and effective way to alleviate menstrual pain, as well as to improve other PD-related symptoms. Despite similar clinical studies for this condition in the past, no high-quality methodology-based clinical trial has been reported to date. The current study aims to assess the efficacy of the AHP compared with the acupoint placebo plaster (APP) and being placed on a waiting-list control group in patients with primary dysmenorrhea.

METHODS/DESIGN

This study is a randomized, single-center, placebo-controlled clinical trial. A total of 180 women with PD will be included and randomly allocated to the AHP, APP and waiting-list (WL) groups in a 1:1:1 ratio. Patients in the AHP group will be provided with herbal plasters (Shaofuzhuyu decoction) on various acupoints: Shenque (CV8), Guanyuan (CV4), Qihai (CV5), Ciliao (BL32) and Zigong (EX-CA1). Women in the APP group will receive placebo plasters on the same acupoints, and no intervention will be given to the WL group until completion of the study. The primary outcome will be pain intensity reduction measured by a Visual Analog Scale (VAS), with other outcome measurements including the Cox Menstrual Symptom Scale (CMSS), the 12-Item Short Form Health Survey (SF-12) and the Participant Global Impression of Change (PGIC). All assessments will be performed at baseline, each menstrual cycle during the treatment course and the follow-up course. Any adverse events will be recorded throughout the study.

DISCUSSION

This is the first study to compare the changes in menstrual pain after three different interventions: the active intervention (AHP), the placebo intervention (APP), and a period of no intervention (WL). This three-arm randomized controlled trial (RCT) aims to investigate the relative contributions of the specific (AHP vs. APP) and non-specific (APP vs. WL) effects to the overall clinical effects of the active AHP on women with PDM. The scientific and rigorous methodology design of this trial should gather good evidence to assess the curative effects and safety of the AHP on PD. Moreover, the results of this study may provide evidence-based references for the treatment of menstrual pain in future.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ID: ChiCTR-TRC-16008701. Registered on 22 July 2016.

Rates of Anovulation in Adolescents and Young Adults with Moderate to Severe Primary Dysmenorrhea and Those without Primary Dysmenorrhea

STUDY OBJECTIVE

To evaluate rates of presumptive anovulation in eumenorrheic adolescents and young adults with moderate to severe primary dysmenorrhea and those without primary dysmenorrhea.

DESIGN

Participants completed luteinizing hormone surge ovulation predictor test kits. Anovulatory cycles were defined by never receiving a positive result before the next menstrual period; participants were grouped as anovulatory if they experienced at least 1 anovulatory cycle during study participation. Participants rated daily level of menstrual pain on a 0-10 numeric rating scale.

SETTING

A university-based clinical research laboratory.

PARTICIPANTS

Thirty-nine adolescents and young adults (ages 16-24) with primary dysmenorrhea and 52 age-matched control girls.

INTERVENTIONS AND MAIN OUTCOME MEASURES

Rates of presumptive anovulation.

RESULTS

One hundred sixty-eight cycles were monitored, 29.8% (N = 50) of which were anovulatory (37.1% [39/105] vs 17.5% [11/63] of cycles in control and dysmenorrhea groups, respectively). During study participation, control girls were significantly more likely to have had at least 1 anovulatory cycle than were girls with primary dysmenorrhea (44.2% [23/52] vs 17.9% [7/39] of participants, respectively; P < .01). Cycle length and number of bleeding days between ovulatory and anovulatory cycles were similar. The primary dysmenorrhea group's maximum menstrual pain ratings did not differ between ovulatory and anovulatory cycles (4.77 and 4.36, respectively; P > .05).

CONCLUSION

Our data support previous findings of increased rates of ovulation in primary dysmenorrhea. However, menstruation after anovulatory cycles can be as painful as menstruation after ovulatory cycles. These data support the idea that regular menses do not necessarily indicate that a normal ovulatory cycle has occurred. Previous implications that ovulation is necessary for the development of substantial menstrual pain are incomplete.

Analgesic Properties of Nigella Sativa and Eucheuma Cottonii Extracts

BACKGROUND

This study investigates the analgesic properties of the aqueous extracts of Nigella sativa and Eucheuma cottonii in mice. The analgesic properties of both extracts were evaluated in an experimental model of acetic acid-induced writhing test.

MATERIALS AND METHODS

The mice were divided into four different groups and received the test extracts and the standard drug (aspirin) for 14 days via force-feeding. On day 15, the mice were injected with 5% acetic acid, and the number of abdominal constriction and elongation of hind limb (writhes) were counted for 20 min.

RESULTS

The numbers of writhes were counted starting after 5 min of the acetic acid injection. The N. sativa extracts significantly reduced the number of writhes as compared to the control group. Both of the extracts revealed a comparable result as referred to the aspirin effects in the mice.

CONCLUSIONS

These findings indicate that N. sativa and E. cottonii may possess protective active constituent that is effective in reducing the sensation of pain in mice.

Effects of acupoint-stimulation for the treatment of primary dysmenorrhoea compared with NSAIDs: a systematic review and meta-analysis of 19 RCTs

Background

Primary dysmenorrhoea (PD), defined as painful menses in women with normal pelvic anatomy, is one of the most common gynaecological syndromes. Acupoint-stimulation could potentially be an effective intervention for PD. Our aim was to determine the effectiveness of acupoint-stimulation compared with Non-Steroidal Anti-Inflammatory Drugs (NASIDs) in the treatment of PD.

Methods

Six databases were searched to December 2014. Sixteen studies involving 1679 PD patients were included. We included randomized controlled trials that compared acupoint-stimulation with NASIDs for the treatment of PD. The main outcomes assessed were clinical effectiveness rate, symptom score, visual analogue score, variation in peripheral blood prostaglandin F2α (PGF2α) and side effects. All analyses were performed using Comprehensive Meta-Analysis statistical software.

Results

(1) The total efficacy was better than control group: odds ratio = 5.57; 95% confidence interval (95% CI) = 3.96, 7.83; P < 0.00001; (2) The effect of intervention was positive in relieving the severity of PD symptoms: mean difference (MD) = 2.99; 95%CI = 2.49, 3.49; P < 0.00001; (3) No statistical difference existed between two groups in terms of a reduction in the VAS: MD = 1.24; 95%CI = −3.37, 5.85; P = 0.60; (4) The effect of intervention on the variation in peripheral blood PGF2α between two groups was positive: MD = 7.55; 95%CI = 4.29,10.82; P < 0.00001; (5) The side effects of control groups was more than the acupoint-stimulation group: OR = 0.03; 95%CI =0.00,0.22; P = 0.0005.

Conclusions

According to this article, acupoint-stimulation can relieve pain effectively in the treatment of PD and offers advantages in increasing the overall effectiveness.

Acute Pain Management

Acute pain management is improving steadily over the past few years, but training and professional education are still lacking in many professions. Untreated or undertreated acute pain could have detrimental effects on the patient in terms of comfort and recovery from trauma or surgery. Acute undertreated pain can decrease a patient's vascular perfusion, increase oxygen demand, suppress the immune system, and possibly risk increased incidence of venous thrombosis. Although acute postoperative pain needs to be managed aggressively, patients are most vulnerable during this period for developing adverse effects, and therefore, patient assessment and careful drug therapy evaluation are necessary processes in therapeutic planning. Acute pain management requires careful and thorough initial assessment and follow-up reassessment in addition to frequent dosage adjustments, and managing analgesic induced side effects. Analgesic selection and dosing must be based on the patient's past and recent analgesic exposure. There is no single acute pain management regimen that is suitable for all patients. Analgesics must be tailored to the individual patient.

Antinociceptive properties of new coumarin derivatives bearing substituted 3,4-dihydro-2H-benzothiazines

Background

Coumarins are an important class of widely distributed heterocyclic natural products exhibiting a broad pharmacological profile. In this work, a new series of coumarins bearing substituted 3,4-dihydro-2H-benzothiazines were described as potential analgesic agents. The clinical use of NSAIDs as traditional analgesics is associated with side effects such as gastrointestinal lesions and nephrotoxicity. Therefore, the discovery of new safer drugs represents a challenging goal for such a research area.

Results

The target compounds 3-(3-methyl-3,4-dihydro-2H-benzo[b][1,4]thiazin-3-yl)-2H-chromen-2-ones 2a-u were synthesized and characterized by spectral data. The antinociceptive properties of target compounds were determined by formalin-induced test and acetic acid-induced writhing test in mice. Among the tested compounds, compound 2u bearing 2-(4-(methylsulfonyl)benzoyl)- moiety on benzothiazine ring and 4-(methylsulfonyl)phenacyloxy- group on the 7 position of coumarin nucleus showed better profile of antinocecieption in both models. It was more effective than mefenamic acid during the late phase of formalin-induced test as well as in the acetic acid-induced writhing test.

Conclusion

Considering the significant antinoceciptive action of phenacyloxycoumarin derivatives, compound 2u prototype might be further used as model to obtain new more potent analgesic drugs.

Nonsteroidal anti-inflammatory drugs in the treatment of low back pain

Low back pain (LBP) is amongst the top ten most common conditions presenting to primary care clinicians in the ambulatory setting. Further, it accounts for a significant amount of health care expenditure; indeed, over one third of all disability dollars spent in the United States is attributable to low back pain. In most cases, acute low back pain is a self-limiting disease. There are many evidence-based guidelines for the management of LBP. The most common risk factor for development of LBP is previous LBP, heavy physical work, and psychosocial risk factors. Management of LBP includes identification of red flags, exclusion of specific secondary causes, and comprehensive musculoskeletal/neurological examination of the lower extremities. In uncomplicated LBP, imaging is unnecessary unless symptoms become protracted. Reassurance that LBP will likely resolve and advice to maintain an active lifestyle despite LBP are the cornerstones of management. Medications are provided not because they change the natural history of the disorder, but rather because they enhance the ability of the patient to become more active, and in some cases, to sleep better. The most commonly prescribed medications include nonsteroidal anti-inflammatory drugs (NSAIDs) and muscle relaxants. Although NSAIDs are a chemically diverse class, their similarities, efficacy, tolerability, and adverse effect profile have more similarities than differences. The most common side effects of NSAIDs are gastrointestinal. Agents with cyclo-oxygenase 2 selectivity are associated with reduced gastrointestinal bleeding, but problematic increases in adverse cardiovascular outcomes continue to spark concern. Fortunately, short-term use of NSAIDs for LBP is generally both safe and effective. This review will focus on the role of NSAIDs in the management of LBP.

Synthesis, spectral characterization, and pharmacological screening of some 4-[{1-(aryl)methylidene}-amino]-3-(4-pyridyl)-5-mercapto-4H-1,2,4-triazole derivatives

Background:

Pain is an unpleasant and subjective sensation that results from a harmful sensorial stimulation, which alerts the body about current or potential damage to its tissues and organs. Fever is a complex physiological response triggered by infections or aseptic stimuli. Elevation in body temperature occurs when the concentration of prostaglandin E₂ (PGE₂) increases within parts of the brain. Triazole derivatives have been found to possess various pharmacological and biological activities, such as, anti-inflammatory, analgesics, antipyretic, and antifungal.

Materials and Methods:

Various 4-[{1-(aryl)methylidene}-amino]-3-(4-pyridyl)-5-mercapto-4H-1,2,4-triazole derivatives were synthesized by a sequence of reactions starting from isonicotinic acid hydrazide. The synthesized compounds were screened for in-vivo analgesic by the tail-flick method and anti-pyretic activities at a dose of 25 and 100 mg/kg body weight respectively. The antipyretic activity was evaluated using Brewer's yeast induced pyrexia in rats. Fever was induced by subcutaneously injecting 20 ml/kg of 20% aqueous suspension of Brewer's yeast in normal saline.

Results and Discussion:

The analgesic screening results revealed that the compounds 3b, 3c, and 3d exhibited excellent analgesic activity at 60 and 90 minutes compared to the standard drug (Analgin). Results revealed that the compounds 3a, 3e, and 3f significantly decreased the temperature of pyretic (P<0.001) rats at one, three and six hours after compound administration as compared to Aspirin (standard drug).

Conclusion:

Compounds 3b, 3c, and 3d exhibited significant analgesic activity comparable with the standard drug analgin, using the tail flick model. Compounds 3a, 3e, and 3f showed significant anti-pyretic activities comparable with the standard drug aspirin using the yeast-induced pyrexia model.

The effect of Cox-2 specific inhibition on direct fracture healing in the rabbit tibia

OBJECTIVE

The purpose of this study was to evaluate the effect of Cox-2 administration on direct (primary) fracture healing.

METHODS

A transverse tibial osteotomy was created in adult male rabbits and rigidly fixed in compression using a 2.7-mm dynamic compression plate. Animals were randomized to receive either rofecoxib (12.5 mg orally per day) or placebo. Animals were killed at 4 weeks and fracture healing assessed by mechanical testing.

RESULTS

There were no significant differences between the control and Cox-2 treated animals in terms of mechanical strength at 4 weeks. There was a high complication rate of peri-implant fractures during the daily medication administration.

CONCLUSION

The immediate administration of a Cox-2 specific inhibitor did not impair primary (direct) bone healing at the dose administered in this rabbit tibial osteotomy model.

[Postoperative pain management for patients who are long-term users of opioid]

Pain is one of the most common reasons for seeking medical care and the frequency of prescription of opioid analgesics by both primary care physicians and specialists has increased. It is therefore unsurprising that many patients with chronic pain who must undergo scheduled or emergency surgery will be on long-term medication, including opioids. Managing postoperative pain, even with high doses of drugs, seems to be more difficult in regular users of such analgesics, possibly because of an apparent association of opioid use with increased tolerance and hyperalgesia. Postoperative pain relief should be carefully tailored in these cases by means of a management plan worked out along with the patient. Adjuvants may be particularly useful; the most thoroughly studied adjuvants are nonsteroidal anti-inflammatory drugs and ketamine. Regional anesthesia offers a particularly attractive approach when long-term users of opioids must undergo surgery.

Analgesic, anti-pyretic and DNA cleavage studies of novel pyrimidine derivatives of coumarin moiety

A novel series of 4-[4-(6-phenyl-pyrimidin-4-yl)-phenoxymethyl]-chromen-2-ones [5-7(a-e)] were synthesized from various 4-bromomethyl coumarins 1(a-e). The synthesized compounds were screened for in-vivo analgesic and anti-pyretic activities at a dose of 25 and 100 mg/kg body weight (b.w), respectively. Among them, compounds 5(d), 6(c) and 7(d) exhibited significant analgesic activity comparable with standard drug analgin using Tail-flick model. Compounds 5(a) and 7(a-d) showed significant anti-pyretic activities comparable with standard drug aspirin using yeast-induced pyrexia model. DNA cleavage study by agarose gel electrophoresis method was also studied. Qualitative SAR studies indicate that, compounds with amino group at 2-position of pyrimidine ring enhances analgesic and anti-pyretic activities and compounds with hydroxyl and thio group at 2-position of pyrimidine ring increase DNA cleavage activities.

Diclofenac potassium restores objective and subjective measures of sleep quality in women with primary dysmenorrhea

STUDY OBJECTIVES

Primary dysmenorrhea is a common gynecological disorder that disrupts daytime functioning and nighttime sleep quality. We determined the effectiveness of diclofenac potassium, compared to placebo, in alleviating nighttime pain and restoring sleep architecture in women with primary dysmenorrhea.

DESIGN

Randomized, double-blind, crossover study.

SETTING

Sleep laboratory.

PARTICIPANTS

Ten healthy women (21 +/- 1 years) with a history of primary dysmenorrhea.

INTERVENTIONS

Placebo or diclofenac potassium (150 mg per day) for menstrual pain.

MEASUREMENTS AND RESULTS

We assessed objective measures of sleep (polysomnography) and subjective measures of sleep quality, mood, and intensity of menstrual pain. Compared to a pain-free phase of the menstrual cycle (mid-follicular), women receiving placebo for their menstrual pain had a poorer mood (P < 0.01), decreased sleep efficiency (P < 0.05), less REM sleep (P < 0.05), more stage 1 sleep (P < 0.01), and more sleep stage changes per hour of sleep during the night. Administration of diclofenac potassium compared to placebo not only attenuated the women's menstrual pain (P < 0.05), but also increased sleep efficiency (P < 0.05) and percentage of REM sleep (P < 0.01), decreased percentage of stage 1 sleep (P < 0.05) and number of sleep stage changes per hour of sleep (P < 0.05), and improved subjective ratings of sleep quality and morning vigilance (P < 0.05).

CONCLUSION

Diclofenac potassium effectively attenuates nighttime dysmenorrheic pain and restores subjective and objective measures of sleep quality to values recorded in a pain-free phase of the menstrual cycle.

Peripherally acting mu-opioid receptor antagonists and postoperative ileus: mechanisms of action and clinical applicability

Postoperative ileus (POI), a transient cessation of coordinated bowel function after surgery, is an important health care problem. The etiology of POI is multifactorial and related to both the surgical and anesthetic pathways chosen. Opioids used to manage surgical pain can exacerbate POI, delaying gastrointestinal (GI) recovery. Peripherally acting mu-opioid receptor (PAM-OR) antagonists are designed to mitigate the deleterious effects of opioids on GI motility. This new class is investigational for POI management with the goal of accelerating the recovery of upper and lower GI tract function after bowel resection. In this review, we summarize the mechanisms by which POI occurs and the role of opioids and opioid receptors in the enteric nervous system, discuss the mechanism of action of PAM-OR antagonists, and review clinical pharmacology and Phase II/III POI trial results of methylnaltrexone and alvimopan. Finally, the role of anesthesiologists in managing POI in the context of a multimodal approach is discussed.

Adynamic ileus and acute colonic pseudo-obstruction

Ileus and colonic pseudo-obstruction cause functional obstruction of intestinal transit, without mechanical obstruction, because of uncoordinated or attenuated intestinal muscle contractions. Ileus usually arises from an exaggerated intestinal reaction to abdominal surgery that is often exacerbated by numerous other conditions. Colonic pseudo-obstruction is induced by numerous metabolic disorders, drugs that inhibit intestinal motility, severe illnesses, and extensive surgery. It presents with massive colonic dilatation with variable, moderate small bowel dilatation. Both conditions are initially treated with supportive measures that include intravenous rehydration, correction of electrolyte abnormalities, discontinuation of antikinetic drugs, and treatment of other contributing disorders. Specific therapies for colonic pseudo-obstruction include neostigmine (an anticholinesterase) for pharmacologic colonic decompression and colonoscopic decompression.

The effect of three cyclo-oxygenase inhibitors on intensity of primary dysmenorrheic pain

OBJECTIVE

To determine the effect of 3 different cyclo-oxygenase (COX) inhibitors on primary dysmenorrheic pain.

METHOD

Eleven female patients self-medicated with either placebo (sugar), 25 mg of the COX-2 specific inhibitor rofecoxib, 50 mg of the nonselective COX inhibitor diclofenac potassium, or 7.5 mg of the COX-2 selective inhibitor meloxicam, over 4 menstrual cycles. Pain was assessed using the McGill Pain Questionnaire and a visual analog scale.

RESULTS

The pain response index, present pain index, and visual analog scale were highly correlated as measures of intensity of pain (r=0.81 to 0.96, P<0.0001). Rofecoxib and diclofenac potassium both decreased the duration of dysmenorrheic pain compared with placebo (P<0.001) and with meloxicam (P<0.01), and were equally effective in improving pain, compared with placebo, after each capsule (P<0.001). When compared with placebo, both drugs also provided 50% or more pain relief, after each capsule (P<0.0048). Meloxicam, although superior to placebo, was not as effective as rofecoxib and diclofenac potassium in reducing pain, and when compared with placebo, was associated with providing 50% or more of pain relief only after the third and fourth capsules (P=0.016).

CONCLUSIONS

Rofecoxib and diclofenac potassium, when taken in recommended doses, were equally effective in alleviating pain associated with primary dysmenorrhea.

Nimesulide in the treatment of postoperative pain: a double-blind, comparative study in patients undergoing arthroscopic knee surgery

OBJECTIVE

To evaluate the efficacy and tolerability of nimesulide in the relief of postoperative pain after orthopedic surgery compared with naproxen and placebo.

METHODS

In this multicenter, double-blind, double-dummy, randomized, parallel group study, 94 patients with at least moderate postoperative pain after arthroscopy and meniscectomy were randomized to receive nimesulide 100 mg b.i.d., naproxen 500 mg b.i.d., or placebo for a maximum of 3 days.

RESULTS

Nimesulide was significantly more effective than placebo for the treatment of postoperative pain, as measured by the primary efficacy variable of summed pain intensity difference within 6 hours after first treatment (10.91 vs. 6.29). Furthermore, nimesulide also provided significantly better pain relief than naproxen on this parameter. Overall, nimesulide demonstrated superior analgesic activity compared with naproxen and placebo for the majority of secondary efficacy variables. All 3 treatments were well tolerated, with a lower number of patients reporting adverse events in the nimesulide group. Nimesulide recipients reported no gastrointestinal disorders.

CONCLUSIONS

This study demonstrates that nimesulide is an effective, fast-acting and well-tolerated oral anti-inflammatory drug with a distinct analgesic activity after out-patient orthopedic surgery.

Orofacial pain in cancer: part II--clinical perspectives and management

Cancer-associated pain is extremely common and is associated with significant physical and psychological suffering. Unfortunately, pain associated with cancer or its treatment is frequently under-treated, probably due to several factors, including phobia of opioids, under-reporting by patients, and under-diagnosis by healthcare workers. The most common etiology of cancer pain is local tumor invasion (primary or metastatic), involving inflammatory and neuropathic mechanisms; these have been reviewed in Part I. As malignant disease advances, pain usually becomes more frequent and more intense. Additional expressions of orofacial cancer pain include distant tumor effects, involving paraneoplastic mechanisms. Pain secondary to cancer therapy varies with the treatment modalities used: Chemo-radiotherapy protocols are typically associated with painful mucositis and neurotoxicity. Surgical therapies often result in nerve and tissue damage, leading, in the long term, to myofascial and neuropathic pain syndromes. In the present article, we review the clinical presentation of cancer-associated orofacial pain at various stages: initial diagnosis, during therapy (chemo-, radiotherapy, surgery), and in the post-therapy period. As a presenting symptom of orofacial cancer, pain is often of low intensity and diagnostically unreliable. Diagnosis, treatment, and prevention of pain in cancer require knowledge of the presenting characteristics, factors, and mechanisms involved.

Design and synthesis of 3,4-methylenedioxy-6-nitrophenoxyacetylhydrazone derivatives obtained from natural safrole: new lead-agents with analgesic and antipyretic properties

In this work, we reported the synthesis and evaluation of the analgesic, anti-inflammatory, and antipyretic properties of new 2-(6-nitro-benzo[1,3]dioxol-5-yloxy)-acetylhydrazone derivatives (3), designed exploring molecular hybridization and isosteric replacement approaches between nimesulide (1) and carbanalogue NAH series (2) developed at LASSBio. Target compounds were synthesized in very good yields exploiting abundant Brazilian natural product safrole (4) as starting material. The evaluation of the antinociceptive properties of this series led us to discover a new potent prototype of analgesic and antipyretic agent, that is, NAH derivative 3c, named LASSBio-891, which showed to be more potent than dipyrone used as standard.

The analgesic effect of low dose focal irradiation in a mouse model of bone cancer is associated with spinal changes in neuro-mediators of nociception

Despite the widespread use of radiotherapy to treat painful bone metastases, the mechanism underlying the analgesic effect of low dose ionizing radiation is unknown. Bone cancer pain is mostly associated with an inflammatory response dominated by local activation of osteoclasts and by astrogliosis in the spinal cord. We determined the effects of a 6 Gy irradiation given focally on osteolytic sarcoma cells inoculated in humeri of mice. Pain behavior was assessed using the rota-rod and the grip force test. Seven days post-irradiation (day 17 post-tumor implantation) the performance of mice markedly improved on the rotarod (non-irradiated, 67+/-16s vs irradiated, 223 +/- 22 s; P = 0.0005), and the grip force test (non-irradiated, 34 +/- 4 g vs irradiated, 55 +/- 2 g; P = 0.001). This improvement was similar to the analgesia achieved with 30 mg/kg of the cyclooxygenase (COX) inhibitor ketorolac (Rota-rod, 67 +/- 16 s vs 178 +/- 35 s; P = 0.01: grip force test, 34 +/- 4 g, vs 60 +/- 5 g; P = 0.003). Following irradiation, the tumor mass and the number of osteoclasts did not decrease while the expression of two pro-inflammatory cytokines (monocyte chemoattractant protein (MCP)-1 and tumor necrosis factor (TNF)-alpha) increased. Tumor irradiation led to clear differences in the spinal cord. These include a decrease in glial activity (astrocytes and microglial cells) as well as pain mediators such as dynorphin, COX-2 and chemotactic cytokine receptor (CCR2). We conclude that the analgesic effect of low dose irradiation of bone cancer is associated with the alteration of nociceptive transmission in the central nervous system.

Prevention and treatment of postoperative pain with particular reference to children

Pain therapy is an important aspect of medical practice for patients of all ages, to optimize care, to obtain an adequate quality of life and to improve their general conditions. Pain is among the most prevalent symptoms experienced by patients undergoing surgery. The success of postoperative pain therapy depends on the ability of the clinician to assess the presenting problems, identify and evaluate pain syndromes and formulate a plan for comprehensive continuing care. The prevalence of acute pain has led to the need to develop techniques for the assessment and management of this symptom in order to focus the attention on an interdisciplinary therapeutic approach (including pharmacologic, cognitive-behavioral, psychologic and physical treatment) and on the timing of different interventions (pre and postoperative). In this chapter we describe the principal therapeutic approaches to control pain in post-operative patients, such as non-opioid, opioid and adjuvant analgesics with particular attention in paediatric age. Moreover we report the principal scales to assess the pain intensity in the post-operative period. The need of a multidisciplinatory team and of a pre and postoperative pain management program represents an important goal in order to obtain effective pain relief and optimize pediatric care and rapid recovery. The introduction of a perioperative team service will improve the approach to pain management programs and it is considered the most important challenge for future.