Pain Perception Research Articles

Effect of experimental knee pain location on gait kinematics

Abstract Purpose In this study, we investigated whether experimental knee pain alters lower limb kinematics and knee arthrokinematics during gait, and if this motor adaptation depends on the spatial characteristics of the painful stimulus. Methods Twenty-one participants walked on a treadmill for 60-s trials, either without stimulation or while experiencing painful electrical stimulation in the medial, lateral or anterior region of the knee. Perceived pain location was analyzed using pain drawing. Gait spatiotemporal parameters, lower limb kinematics, and dispersion of the knee helical axes on the sagittal plane were quantified for each trial and compared between conditions using ANOVAs with repeated measures or Friedman tests. Results Pain perception was localized in the area the stimulation was applied to. Compared to walking without pain, participants demonstrated reduced knee extension (1.5 ± 1.5 degrees, p = 0.002) and reduced hip extension (0.8 ± 1.1 degrees, p = 0.037) when pain was induced in the anterior region, but not medially or laterally. Anterior knee pain increased the mean distance of the helical axes during late stance (0.7 [0.3, 1.4], p = 0.010), while medial pain increased both mean distance (0.3 [0.1, 0.5], p = 0.037) and mean angle (1.2 ± 1.4, p = 0.010) during early swing. Conclusion Acute, experimental knee pain alters gait kinematics and increases the dispersion of the helical axis. These adaptations depend on the spatial characteristics of the painful stimulus. These adaptations may reflect an attempt of the central nervous system to protect the painful tissue while searching for a less painful movement strategy.

A Comprehensive Systematic Review of Depression and Anxiety in Adults with Pyoderma Gangrenosum

Background: Pyoderma gangrenosum (PG) is a rare, chronic inflammatory skin disease characterized by painful, necrotic ulcers that frequently lead to disfiguring scars and significantly impact patients’ quality of life. This interplay between PG and mental health issues like anxiety and depression underscores the need for holistic approaches to manage both the physical and psychological challenges faced by PG patients. Methods: This systematic review adhered to the PRISMA 2020 guidelines, focusing exclusively on full-text articles published in English between 2015 and 2024. Result: A total of over 600 publications were initially identified through the database search. Following a rigorous three-stage screening process, eight studies were selected for comprehensive analysis. These studies were critically examined to provide an in-depth evaluation of depression and anxiety among adults with pyoderma gangrenosum. Conclusion: Pyoderma gangrenosum, a chronic autoimmune disorder, significantly impacts patients' mental health due to painful ulcers, visible lesions, and social isolation. Untreated depression can exacerbate pain perceptions and reduce treatment satisfaction. Healthcare providers must screen for and address mental health conditions in PG patients, utilizing psychological support and counseling to address both physical and mental health issues.

Differential neural activity predicts the long-term stability of the effects of positive and negative expectations on pain

AbstractExpectations modulating pain perception is a well-researched phenomenon, but less is known about the persistence of expectation effects over longer time-courses. In this preregistered study, we examined the persistence of positive (placebo) and negative (nocebo) expectation effects over one week and investigated whether neural activity on day 1 (fMRI) can predict the stability of these effects one week later (n = 41). We tested whether expectations were reflected in EEG oscillatory activity at the second measurement. Both positive and negative pain modulation effects persisted over the tested time-period and did not undergo extinction. Expectations of higher compared to lower pain led to larger theta-to-alpha EEG activity. Most interestingly, differential neural activity in fMRI was correlated with persistent expectations. Individual differences in the persistence of positive expectation effects were related to reduced amygdala activity and enhanced activity in the anterior insula and dorsolateral prefrontal cortex (DLPFC) during the first session. In contrast, persistence of negative expectation effects was predicted by enhanced thalamus activity. Our findings indicate relatively stable placebo and nocebo effects over longer time courses, but this persistence is based on different neural areas for positive and negative expectations.

Clinical Outcome and Quality of Life after Modular Reverse Total Shoulder Arthroplasty in Comparison with Joint‐Preserving Locking Plate Osteosynthesis in Aged Patients: A Retrospective Comparison Study

ObjectivesProximal humeral fractures (PHFs) show a high incidence in aged patients. While nondisplaced fractures achieve good results by conservative treatment, surgical procedures are discussed controversially. Next to open reduction and internal fixation (ORIF), the primary use of reverse shoulder arthroplasty (RSA) has become increasingly important. The aim of this study was to investigate the clinical function, activities of daily living (ADL), as well as pain assessment in patients with PHFs, treated by ORIF or RSA.MethodsA retrospective comparison study was assessed. From November 2011 to March 2016, 34 patients (17 matched pairs) that had undergone either ORIF or RSA of the proximal humerus, were included in this study. Pain was measured by numeric rating scale (NRS). ADL were obtained by Katz‐Index and SF‐12. Moreover, shoulder function was assessed using the Oxford Shoulder Score (OSS). The maximum range of motion (ROM) was also recorded. From November 2011 to March 2016, 34 patients (17 matched pairs) that had undergone either ORIF (Figure or RSA of the proximal humerus) were included in this study. For statistical analyses, Student's t‐test, Wilcoxon test, and Chi‐Quadrat test were used. Statistical significance was indicated with p < 0.05.ResultsTotally 34 patients with an average age of 76.6 years were included. Surgical treatment was performed on average 5.2 days after diagnosis, differing significantly between the two groups (RSA/ORIF: 6.9/3.5 days) The operation time of RSA (97 min) was significantly longer than for ORIF (78 min). Pain assessment, as well as the Katz‐Index and the SF‐12, showed no significant differences. Moreover, clinical shoulder function showed no significant discrepancies between the two surgical techniques.ConclusionsAged patients with PHFs treated with RSA display similar results regarding clinical function, ADL as well as pain perception compared with ORIF. However, revision surgery rate was lower in patients who underwent RSA. Thus, the surgical treatment of PHFs by RSA represents an excellent alternative, especially with regard to an aging patient population.

CNSC-13. CROSSTALK BETWEEN SENSORY NEURONAL ACTIVITY AND TUMOR CELLS PROMOTES MALIGNANCY AND CANCER PAIN

Abstract BACKGROUND Nerve infiltration of solid tumors is associated with poor prognosis in multiple cancer types. Understanding the role of neuronal activity in cancer progression offers innovative approaches for treating malignancies and cancer-associated neurological issues such as pain. Pain perception is mediated by the activity of peripheral sensory neurons. Many cancer types induce pain, and sensory innervation could support tumor growth, raising the interesting hypothesis that cancer pain-associated neuronal activity promotes malignancies. Our study aims to test the hypothesis using malignant peripheral nerve sheath tumor (MPNST) as the experimental platform. METHODS in vivo allograft models were established by implanting mouse MPNST cells into the sciatic nerves of male and female mice, followed by performing pain behavior assays (von Frey, Hargreaves, and conditioned place preference tests) and tumor growth measurements. Primary mouse dorsal root ganglion (DRG) sensory neuron cultures were prepared for calcium imaging and neuron-tumor co-culture experiments. RESULTS MPNST tumor-bearing mice exhibited hypersensitivity to noxious and non-noxious stimuli (evoked pain) and ongoing pain, compared to the sham controls. MPNST-conditioned media increased intracellular calcium concentration and ATF3 (indicator for nerve injury/stress) expression in primary sensory neuron culture, suggesting that MPNST tumor cell secretory factors may induce pain by triggering sensory neuron injury/stress responses that increase sensory neuron activity/sensitivity. Reciprocally, we found that stimulation of sensory neuron activity accelerates MPNST tumor growth. The conditioned media from stimulated sensory neurons increased tumor proliferation (EdU assay) in vitro, suggesting that sensory neuron activity-induced paracrine factors increase MPNST cell growth. CONCLUSIONS MPNST is a devastating cancer that grows within peripheral nerves which induce intractable pain. Our findings demonstrate a feedforward cycle where the cancer cells induce sensory neuron hypersensitivity/hyperactivity (pain) which in turn further accelerates tumor growth. Future studies will identify the molecular mechanisms underlying this crosstalk between MPNST and sensory neuron activity.

Effect of swearing on physical performance: a mini-review

Swearing, or using taboo language with the potential to offend, has been shown to improve physical performance during short and intense tasks requiring strength and power development. While consistent ergogenic effects of swearing have been observed across studies, the mechanisms by which swearing impacts physical performance are not fully clear. Swearing has been shown to modulate physiological (i.e., heart rate, blood pressure, skin conductance), psychological (i.e., state disinhibition), and nociceptive (i.e., pain threshold, pain tolerance, pain perception) responses, thus making it plausible that these mechanisms allow swearing to positively impact physical performance. A variety of dosages of swearing (i.e., word used, intensity, frequency, quantity) have been reported to improve physical performance. Although habituation to the positive physical performance effects of swearing has not been explored formally through empirical research, habituation to swearing has been observed in other contexts. From a practical application standpoint, swearing represents a low-risk, effective, and inexpensive intervention that has the potential to acutely improve physical performance although the taboo nature of swearing may limit its utility in real-world situations. The purpose of the following review is to provide an overview of available evidence on swearing and physical performance and discuss likely underlying mechanisms. Exploration of different swearing approaches and habituation will also be highlighted and suggestions for future research will be discussed, to more comprehensively understand if swearing can be strategically used for performance enhancement.

Primjena ibuprofena u pedijatrijskoj populaciji

Fever is a common clinical issue, causing concern for parents and being the most frequent reason for visits to pediatricians and pediatric emergency services. Pain accompanies children in various pathological conditions during their growth. Although the importance of pain perception and the use of analgesics is emphasized, pain in the pediatric population is still insufficiently recognized, unlike fever. Ibuprofen is one of the most commonly used medications in the pediatric population, indicated for reducing fever, as well as relieving pain and inflammation in various diseases. The pharmacological properties of ibuprofen indicate a good safety profile with effective results, contributing to its widespread use. The most commonly expected adverse reactions, considering the mechanism of action, such as gastrointestinal bleeding, are rare in children. In a healthy child, there are no adverse effects on the kidneys; however, in conditions of dehydration or kidney disease, fluid volume should be replenished before administering ibuprofen. Given its broad application during fever caused by infection, some conditions are associated with more severe clinical skin and respiratory infections. It is also linked to exacerbations of asthma and a higher risk of asthma if used during pregnancy and the early years of life.This potential association requires additional research to be methodologically confirmed. Therefore, in this paper, through a literature review, we present the effectiveness and safety of ibuprofen use in the pediatric population in various pathological condition.

Comparative evaluation of pain rating scales for dental pain among the Saudi population: A cross-sectional study

Pain, being a subjective phenomenon, is perceived in different manner by individuals based on various factors including age and gender. Various scales are available in literature to assess and record the pain perceived by an individual. Comparison of commonly used pain perception scales among Saudi Arabian population is scarce. A cross-sectional observational study was conducted among 180 subjects who were belonging to 2 age groups namely 7 to 16 years (group 1; n = 90) and 51 to 60 years (group II; n = 90). Subjects with dental pain of pulpal origin were included by employing consecutive sampling. The included participants were asked to record the severity of pain using visual analogue scale (VAS) and Wong Baker facial pain rating scale (WBS) in a computer-generated random order. The data obtained was subjected to statistical analysis. t test was used to compare the pain score recorded using VAS and WBS among males and females. The correlation between VAS and WBS was also assessed. P value < 0.05 was considered statistically significant. All subjects who participated responded to both the pain perception scales. No difference was found between males and females in the pain perception recorded using VAS and WBS in both the groups. A strong positive correlation was found between VAS and WBS score which was found to be statistically significant in both the groups. Both VAS and WBS are reliable tool to record pain perception in both age groups. WBS is found to be easier and more convenient one.

Prospectively predicting 6-month risk for non-suicidal self-injury among adolescents after psychiatric hospitalization based on a predictive model

BackgroundIt is challenging to predict the occurrence of non-suicidal self-injury (NSSI) among adolescents over short periods. Moreover, the predictive value of indices for NSSI remains elusive. Thus, this study aimed to identify predictors of NSSI within 6 months among adolescents after psychiatric hospitalization by establishing a risk assessment model.MethodsA total of 632 high-risk participants were included in this study. The distribution characteristics of adolescent NSSI were initially assessed through a cross-sectional survey, following which risk factors were identified using logistic regression analysis. The risk score method was then used to construct a 6-month risk assessment model for NSSI. Lastly, the predictive effect of the model was evaluated by indicators such as the area under the receiver operating characteristic (ROC) curve and the positive predictive value.ResultsAfter 6 months, 412 cases of NSSI were identified. According to the logistic regression model, the frequency of relapses, medication status, and NSSI history were identified as influencing factors. Higher scores on the Impulsive Behavior Scale and Pittsburgh Sleep Quality Index were associated with a higher risk of NSSI. Conversely, higher scores on the Pain and Belief Perception Scale were correlated with a lower risk of NSSI. Moreover, the area under the ROC curve for the predictive model was 0.9989, with a 95% confidence interval of (0.9979, 0.9999), highlighting its high predictive ability and accuracy. The predictive model was validated using 78 patients, yielding an area under the ROC curve of 0.9703 and a 95% confidence interval of (0.9167, 0.9999), demonstrating outstanding predictability.ConclusionThese results collectively showed that the predictive model could accurately predict adolescent NSSI. Thus, the model’s primary variables may be applied to predict the risk of NSSI in the clinical setting.

The intangible costs of living with low back pain from a patient perspective: a scoping review

Purpose Health-related low back pain costs can be direct monetary, indirect monetary, or intangible, non-monetary. The purpose of this review was to identify the intangible, non-monetary costs of low back pain from the perspective of the individual. Materials and methods A scoping review of literature was undertaken. Four databases were searched up to 6th August 2024. Data were charted and coded using deductively derived categories in line with our purpose; additional categories were developed for text that did not fit these categories. Data were analysed using directed content analysis. Results Forty-six studies met the inclusion criteria. Six categories were derived from the data, which express the experience of the person with low back pain: Perceptions of pain, Experience of healthcare, Becoming defined by low back pain, Life on hold, My social self, and Disrupted work life. Each category explored an aspect of life affected by low back pain. Conclusion This review highlights that low back pain profoundly affects many areas, with implications for peoples’ personal, social, and work lives. Our findings suggest that suffering can be reduced when healthcare practitioners show empathy and legitimise the lived experience of low back pain, acknowledging the restrictions it imposes on peoples’ lives.

Adequacy of Anesthesia Guidance for Combined General/Epidural Anesthesia in Patients Undergoing Open Abdominal Infrarenal Aortic Aneurysm Repair; Preliminary Report on Hemodynamic Stability and Pain Perception

Adequacy of Anesthesia Guidance for Combined General/Epidural Anesthesia in Patients Undergoing Open Abdominal Infrarenal Aortic Aneurysm Repair; Preliminary Report on Hemodynamic Stability and Pain Perception

Evaluation of Two Mini-implant Lengths in the Infrazygomatic Crest Region: A Randomized Clinical Trial.

Temporary anchorage devices (TADs) have revolutionized fixed orthodontic appliance treatment through anchorage controlling in the clinic and play an essential role in resolving many complex cases. Due to the limited space, there is a risk of injury to the roots while using interradicular microimplants. Therefore, the infrazygomatic crest (IZC) area can be an alternative mini-implant insertion site in the maxillary arch. The aim of the study was to evaluate the primary stability, pain perception, sinus penetration, late stability, and failure rate with two mini-implant lengths in the IZC area. Forty-eight mini-implants (Tusk Dental Co., Ltd., Canada) with two different lengths (length/diameter: 12/2 and 14/2 mm) were grouped by length (24 per group) and inserted bilaterally into the IZC area of 24 patients. The data were statistically analyzed, considering a significance level of p < 0.05. Sinus penetration prevalence did not differ significantly between 12-mm (54.2%) and 14-mm (62.5%) mini-implants (p > 0.05). Primary stability was significantly higher with the 14-mm mini-implants (p < 0.05). The failure rate did not differ significantly between the 12-mm (20.8%) and 14-mm (16.7%) mini-implants (p > 0.05). While the failure rate was similar between 12- and 14-mm mini-implants, the 14-mm mini-implants were more likely to damage adjacent structures. Therefore, shorter mini-implants should be preferred over longer mini-implants for most cases requiring IZC TADs. ClinicalTrials.gov identifier: NCT06293872.

Experiences and perceptions of acute testicular pain, with a focus on reasons for delayed presentation to hospital: a qualitative evidence synthesis

BackgroundThe annual incidence of testicular torsion is approximately 1 in 4000 males under the age of 25. Despite the 97% testicular salvage rate when surgical intervention is within 6 hours...

Complete intraureteral stent placement reduces stent-related pain in normotensive subjects and in diabetes: Subgroup analysis of a prospective randomized clinical trial

Purpose: Pain is a common symptom that is associated with ureteral stent placement, but its degree of perception might vary among individuals. Compared with conventional stent placement (C-SP), complete intraureteral stent placement (CIU-SP) has shown promise in reducing stent-associated pain. This study aimed to investigate the effect of patient characteristics and comorbidities on pain reduction after CIU-SP. Materials and methods: Patients who underwent ureteroscopic lithotripsy and stent placement were randomized into the CIU-SP and C-SP groups. Stent-associated symptoms were evaluated using the Ureteral Stent Symptom Questionnaire on day 7, immediately before stent removal. Stent-associated pain was determined by the answer to question P1 (yes or no). Subgroup analysis was conducted based on various patient characteristics and comorbidities. Results: Of the 103 randomized patients, 91 (45 in CIU-SP and 46 in C-SP) were included in the final analysis. Body pain was reported by 31 (68.9%) after CIU-SP and 41 (89.1%) after C-SP (P = 0.021). Compared with C-SP, CIU-SP significantly reduced pain in the normotensive population (66.7% versus 93.7%, P = 0.006) but not in hypertensive individuals (77.8% versus 76.9%, P = 1.000). Conversely, compared with C-SP, CIU-SP was associated with less pain in patients with diabetes (37.5% versus 88.9%, P = 0.05) but not in patients without diabetes (75.7% versus 89.2%, P = 0.221). Age, sex, stone laterality, body mass index, and smoking status did not influence the reduction of pain after CIU-SP. Conclusion: Compared with C-SP, CIU-SP was effective in reducing stent-associated pain, especially in normotensive and diabetic populations. These findings align with existing literature, which emphasized the potential impact of hypertension on decreased pain perception and highlighted the known association between diabetes and bladder hypersensitivity.

Mechanisms of the Native American pain inequity: predicting chronic pain onset prospectively at 5 years in the Oklahoma Study of Native American Pain Risk.

A pain inequity exists for Native Americans (NAs), but the mechanisms are poorly understood. The Oklahoma Study of Native American Pain Risk (OK-SNAP) addressed this issue and recruited healthy, pain-free NAs and non-Hispanic Whites (NHWs) to attend 2 laboratory visits and assessed mechanisms consistent with the biopsychosocial model of pain: demographics, physical variables, psychosocial factors, and nociceptive/pain phenotypes. Then participants were surveyed every 6 months to assess for chronic pain onset. Results at the 2-year follow-up found that NAs were ∼3x more likely than NHWs to develop chronic pain. Moreover, psychosocial factors (discrimination, stress, pain-related anxiety), cardiometabolic load (higher body mass index and blood pressure, lower heart rate variability), and impaired inhibition of spinal nociception partly mediated the pain inequity. The present study examined mechanisms of chronic pain at the 5-year follow-up for OK-SNAP. Results found that the NA pain inequity worsened-NAs were 4x more likely to develop chronic pain (OR = 4.025; CI = 1.966, 8.239), even after controlling for baseline age, sex assigned at birth, income, and education. Moreover, serial mediation models replicated paths from the 2-year follow-up that linked psychosocial variables, cardiometabolic load, and impaired inhibition of spinal nociception to chronic pain onset. Further, 2 new significant paths were observed. One linked discrimination, stress, sleep problems, and facilitated pain perception to increased pain risk. The other linked discrimination with higher spinal nociceptive threshold and pain risk. These results provide further evidence for a NA pain inequity and identify multiple psychosocial, cardiometabolic, and pronociceptive targets for primary interventions.

Pain beliefs and their relationship with pain, psychological distress and catastrophizing in individuals with Parkinson’s disease

ABSTRACT In Parkinson’s disease (PD), a large number of individuals are confronted with pain. This issue has been receiving increasing attention in literature in recent years, as the complexity of pain in this disease makes its evaluation and treatment challenging. However, psychological variables related to the pain experience have received limited attention, especially when it comes to the exploration of beliefs regarding pain which, to our knowledge, remains unexplored in PD. Pain beliefs are defined as a subset of a patient’s belief system which represents a personal understanding of the pain experience. Four dimensions of pain beliefs have been isolated in literature: mystery, pain permanence, pain constancy and self-blame. Thus, the goal of this study was first to describe pain beliefs in individuals with PD and second, to explore the relationships between pain beliefs and clinical and psychological variables. One hundred and sixty-nine international individuals with PD completed an online survey with socio-demographic and medical data. Participants completed self-report instruments to assess their pain (King’s Parkinson’s Disease Pain Questionnaire, McGill Pain Questionnaire and Brief Pain Inventory), psychological distress (Beck Depression Inventory, short-form and Parkinson Anxiety Scale), pain catastrophizing (Pain Catastrophizing Scale) and pain beliefs catastrophizing (Pain Beliefs and Perception Inventory). The study’s findings revealed that most participants’ beliefs are marked by the dimension of permanence, suggesting that individuals with PD perceive the pain experience as chronic and enduring. Meanwhile, pain is minimally perceived as constant, mysterious, or a source of guilt. Our finding concerning the permanence dimension deserves specific attention: even though this belief is prevalent in our population, it is not, or only weakly, associated with an impact on mood or pain catastrophizing. These results bring forth several hypotheses for understanding, highlighting the role of acceptance, and offer new perspectives toward improving clinical practices in terms of assessing and managing pain in PD.

Pain, quality of life, and integral management in a cohort of patients diagnosed with hypophosphatasia in Colombia

BackgroundHypophosphatasia (HPP; OMIM 241510, 241500, and 146300) is a progressive metabolic, genetic disease with wide clinical heterogeneity, ranging from perinatal lethality to mild or moderate localized symptoms. This study aims to analyze the perception of pain, quality of life, and access barriers to healthcare among patients diagnosed with hypophosphatasia in Colombia. In this document we present pain and quality of life results.MethodsThis study is an observational cohort of 18 HPP patients registered in the Colombian Association of Patients with Lysosomal Storage Diseases and Other Orphan Diseases (ACOPEL) database. We conducted a descriptive analysis using data from three questionnaires (SF-36, Brief Pain Questionnaire (BPQ), and Hypophosphatasia Impact Patient Survey (HIPS); the latter was translated into Spanish and validated for this study.ResultsThe most affected features, according to the SF-36 questionnaire, were overall health, vitality, and pain, with a median score above 67%. Patients' perception of their health status (HIPS questionnaire) was favorable, with 38.9% of cases reporting excellent health. On average, results from the BPQ indicated mild to moderate intensity of current pain experienced by patients. Consistency was observed in the reports of either the absence of pain or the presence of mild to moderate intensity when analyzing the results of the three questionnaires.ConclusionsColombian patients with HPP experience mild to moderate impairment in quality of life and pain that interfere with their daily activities. However, there is wide variability in the results obtained.

Involvement of sphingosine-1-phosphate receptor 1 in pain insensitivity in a BTBR mouse model of autism spectrum disorder

BackgroundAbnormal sensory perception, particularly pain insensitivity (PAI), is a typical symptom of autism spectrum disorder (ASD). Despite the role of myelin metabolism in the regulation of pain perception, the mechanisms underlying ASD-related PAI remain unclear.MethodsThe pain-associated gene sphingosine-1-phosphate receptor 1 (S1PR1) was identified in ASD samples through bioinformatics analysis. Its expression in the dorsal root ganglion (DRG) tissues of BTBR ASD model mice was validated using RNA-seq, western blot, RT-qPCR, and immunofluorescence. Pain thresholds were assessed using the von Frey and Hargreaves tests. Patch-clamp techniques measured KCNQ/M channel activity and neuronal action potentials. The expression of S1PR1, KCNQ/M, mitogen-activated protein kinase (MAPK), and cyclic AMP/protein kinase A (cAMP/PKA) signaling proteins was analyzed before and after inhibiting the S1P-S1PR1-KCNQ/M pathway via western blot and RT-qPCR.ResultsThrough integrated transcriptomic analysis of ASD samples, we identified the upregulated gene S1PR1, which is associated with sphingolipid metabolism and linked to pain perception, and confirmed its role in the BTBR mouse model of ASD. This mechanism involves the regulation of KCNQ/M channels in DRG neurons. The enhanced activity of KCNQ/M channels and the decreased action potentials in small and medium DRG neurons were correlated with PAI in a BTBR mouse model of ASD. Inhibition of the S1P/S1PR1 pathway rescued baseline insensitivity to pain by suppressing KCNQ/M channels in DRG neurons, mediated through the MAPK and cAMP/PKA pathways. Investigating the modulation and underlying mechanisms of the non-opioid pathway involving S1PR1 will provide new insights into clinical targeted interventions for PAI in ASD.ConclusionsS1PR1 may contribute to PAI in the PNS in ASD. The mechanism involves KCNQ/M channels and the MAPK and cAMP/PKA signaling pathways. Targeting S1PR1 in the PNS could offer novel therapeutic strategies for the intervention of pain dysesthesias in individuals with ASD.

Efficacy of anesthetics in an echinoderm based on multifaceted stress biomarkers

Animal care committees remain ambiguous on the need for anesthetics during experimental procedures on invertebrate taxa due to long-standing questioning of their sentience and pain perception. When used, anesthetizing procedures for invertebrates have commonly been adapted from those developed for vertebrates, under the largely unverified assumption that they afford the same benefits. The present study formally tested the efficacy of four common anesthetics of aquatic invertebrates (ethanol, MgCl2, clove oil, MS-222) using behavioural (reaction to physical contact and presence of a predator), physiological (respiration rate), cellular (coelomocytes), and hormonal (cortisol) biomarkers in the holothuroid Cucumaria frondosa (Echinodermata). While subjects recovered from exposures to all anesthetics tested, their responses differed markedly. Ethanol did not immobilize the individuals and concurrently increased their respiration rate, and cellular and hormonal stress markers. MgCl2 and clove oil reduced the behavioural and physiological responses, and decreased the cellular markers, but increased the cortisol levels. Only MS-222 fully immobilized the treated individuals and decreased their respiration rate, both during exposure and throughout ulterior interactions with a predator, while keeping coelomocyte counts and cortisol concentrations at baseline levels. MS-222 thus appears to induce the loss of sensation, representing a promising anesthetic and sedative in soft-bodied aquatic invertebrates.

Physical Activity Level and Time of Participation in a Water Aerobics Project for the Elderly: Analysis of the Association with Quality of life, Musculoskeletal and Osteoarticular Disorders, Chronic Pain and Body Mass Index

The objective was to analyze the association between the physical activity level (PAL) and time of participation in the practice of water aerobics with the variables successful aging (SA), quality of life (QOL), musculoskeletal and osteoarticular disorders (MOD), chronic pain (CP) and body mass index (BMI). The method has a quantitative, descriptive and cross-sectional design. The non-probabilistic sample, for convenience, comprised 101 elderly people over 60 years of age, of both genders, who regularly participate in water aerobics activities in the city of Dois Irmãos, in the state of Rio Grande do Sul. The following instruments were used: Multidimensional Pain Assessment Scale, EUROHIS-QOL, IPAQ, SOC and Body Mass Index. Descriptive analyses of frequency, comparison, correlation and multiple linear regression were used. The results showed that the irregularly active group has adequate perception of QOL and longer participation in water aerobics activities associated with lower intensity of pain perception. Likewise, better QOL and control attitudes are associated with lower prevalence of MOD.