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The gut microbiome plays critical roles in human health and disease. Recent studies suggest it may also be associated with chronic pain and postoperative pain outcomes. In animal models, the composition of the gut microbiome changes after general anesthesia and affects the host response to medications, including anesthetics and opioids. In humans, the gut microbiome is associated with the development of postoperative pain and neurocognitive disorders. Additionally, the composition of the gut microbiome has been associated with pain conditions including visceral pain, nociplastic pain, complex regional pain syndrome, and headaches, partly through altered concentration of circulating bacterial-derived metabolites. Furthermore, animal studies demonstrate the critical role of the gut microbiome in neuropathic pain via immunomodulatory mechanisms. This article reviews basic concepts of the human gut microbiome and its interactions with the host and provide a comprehensive overview of the evidence linking the gut microbiome to anesthesiology, critical care, and pain medicine.

BackgroundThe autonomic nervous system is subserved by the sympathetic and parasympathetic which regulate vital involuntary physiological functions like heart rate. Parasympathetic activity can be measured from the high-frequency component of heart rate variability (HRV), measured via the amplitude of RSA, as a possible predictor for mental health and chronic pain disorders. Therefore, investigators looked to correlate HRV with chronic pain when compared healthy controls.MethodsAs part of a larger ongoing study, patients complete pre-defined questionnaires on their pain condition, potential risk factors, and function. For patients and controls investigators collected performance and cardiac measures (RSA, LF-HRV, heart period) while at rest, walking and lifting tests. This analysis focused on differences in heart rate variability measures between 100 patients and 48 controls.ResultsPreliminary analysis revealed demographic and anthropometric variables varied significantly between groups. When comparing HRV measures, respiratory sinus arrhythmia (RSA) during lying and sitting were significantly decreased in patients compared to controls while heart period lying and walking were significantly increased in patients. Correlation analysis revealed significant positive correlation between RSA during lying and sitting when looking at age, gender, and weight. Heart periods during lying and walking were negatively correlated with gender and weight.DiscussionTo our knowledge it is the first study to look at chronic pain and HRV in the Canadian Forces, while also collecting data on patient reported outcomes, and during various resting and activities. Many potential limitations exist for this study including challenges with respect to controlling for known confounders of heart variability.ConclusionBy establishing heart rate variability as a correlate of chronic pain, the outcome of this project could potentially improve quality of care for patients with these conditions. Further work controlling for confounders and relating HRV to pain severity, subtypes, patient reported outcomes and functional abilities will be required to determine the exact value for clinical decision making.

Nonlinear plasmonic metasurfaces were demonstrated recently as ultracompact tetrahertz (THz) sources, emitting relatively strong single-cycle THz pulses after femtosecond laser illumination. There has been great progress in their ability to generate controlled THz wavepackets; however, their overall emission strength has not yet been optimized. Here we numerically show that by designing a Bragg assisted perfect absorber we can improve the coupling of the pumping laser to the nonlinear metasurface. This results in over an order of magnitude enhancement of the THz signal. Moreover, we show that this method can be combined with other independent optimization schemes to further enhance the radiated THz, reaching over two orders of magnitude emission enhancement compared with previously studied plasmonic metasurfaces.

IntroductionLow back pain (LBP) is a major cause of disability and is progressively becoming worse on a global scale. [1,2] The prevention and rehabilitation of LBP lacks clarity in part due to the heterogeneity of the exercise programs prescribed to treat low back pain. Some authors have proposed stabilizing exercises for lower back pain which exert minimal loads on the spine. [3,4,5] Despite a multitude of existing exercise therapies, McGill has introduced three exercises for rehabilitating lower back pain, termed the McGill Big Three (MGB3). [6,7,8,9,10] These include the curl-up, side plank and bird-dog. The purpose of this review is to investigate the clinical outcomes from prescribing the MGB3 to individuals with chronic LBP.MethodsInclusion criteria were randomized control trials that involved an intervention with MGB3 core stabilization exercises for patients with chronic low back pain. The research included articles published during any period in full English text. Studies were critically reviewed by two authors EL and GG independently and collaboratively.ResultsIn total, four randomized control trials were included in this review. Multiple cohorts, with varying age, demographics and occupation were studied. Outcomes studied included various pain scores, patient reported functional and performance measures.DiscussionControlled clinical trials employing this method in low back pain treatment showed low quality data with mixed statistical significance, and little to no clinical significance irrespective of the measure used or even when compared to baseline. Limitations of these trials are detailed herein.ConclusionCurrently there is limited data supporting the clinical benefit of the McGill approach for the treatment of low back pain based on the available randomized clinical trials. More study is required prior to widespread adoption into clinical practice.

IntroductionLiterature reviews are useful tools for communicating the breadth of scientific discovery for a given topic. Irrespective of the nature of the review, data should be communicated in effective, easy to understand ways. In trying to address these limitations of traditional scientific reviews, we propose using dynamic data driven displays that have been used in multiple other industries to improve communication and decision making. Given the recent interest in the clinical applications of psychedelics for various mental health issues, we chose to test the SENSOR System (Standardized Data Entry and Dashboards for Review of Scientific Studies) as an alternative for an existing review article.MethodsTo validate the SENSOR System, an existing review with a topical, heterogenous, and growing set of studies was selected. In this case we chose the Wheeler et al. review on psychedelics in clinical practice where articles had already been preselected and reviewed. Detailed discussion of this review and the cited papers preceded designing the content and shared links for a Google Form for data intake, Google Drive for article access, and Google Sheets linked to the form intake data.ResultsA total of 46 study entries were made by 2 team members, including 3 articles published since the review to demonstrate the ease of updating the system Various representations of the Google Forms intake data in the SENSOR System dashboard are presented.DiscussionVisual representation of review studies using a dashboard proved feasible and advantageous for numerous reasons. As the technology and guidelines for these systems evolve there is an opportunity to standardize reporting, centralize legacy datasets, streamline the submission process, improve collaboration between researchers, measure relative contribution of participating authors, and improve patient involvement. For the use case of clinical applications of psychedelics, limitations of conveying data accurately includes heterogeneity of study design, dosing, indications, and outcome measures.ConclusionCreation of a system for standardized data entry and dashboards for reviews of scientific studies is a feasible alternative and/or adjunct to the dissemination of summaries through traditional scientific review. There are numerous proposed advantages of the flexible, dynamic, and graphical display that requires further validation.

Background: Significant alterations were recently identified in the composition and putative function of the gut microbiome in women with fibromyalgia. As diet can influence the composition of the gut microbiome, differences in nutritional intake could, in theory, account for some of these specific fibromyalgia microbiome alterations. The current study aims to compare the diet of women with fibromyalgia to that of controls in order to explore possible associations between the intake of certain nutrients, symptom severity and gut microbiome composition. Methods: The study population was comprised of 56 women with fibromyalgia and 68 controls. Dietary intake was assessed using the NIH Automated Self-Administered 24 h recall, following dietitian’s instructions and the completion of a three-day dietary recall. The gut microbiome was assessed by 16S ribosomal RNA gene sequencing of stool samples. Results: Most demographic and anthropometric characteristics were comparable between groups. The average energy and macronutrient intake (total and relative) and overall diet quality score were not different between patients and controls, nor were the main vitamins, minerals, fatty acids, alcohol, caffeine, sugar or fiber intakes. The daily intake of micronutrients and normalized macronutrients in women with fibromyalgia was largely not correlated with disease-specific measures, including pain intensity, fatigue, cognitive symptoms and quality of sleep, or with the relative quantity of almost any of the gut microbiome bacterial taxa differentially abundant in fibromyalgia. Conclusion: These data demonstrate that dietary intakes, as evaluated by self-reported questionnaires, probably cannot explain the syndrome-specific differences in gut microbiome or the clinical phenotype of fibromyalgia.

The following authors were omitted from the original version of this Data Descriptor: Markus Reichstein and Nicolas Vuichard. Both contributed to the code development and N. Vuichard contributed to the processing of the ERA-Interim data downscaling. Furthermore, the contribution of the co-author Frank Tiedemann was re-evaluated relative to the colleague Corinna Rebmann, both working at the same sites, and based on this re-evaluation a substitution in the co-author list is implemented (with Rebmann replacing Tiedemann). Finally, two affiliations were listed incorrectly and are corrected here (entries 190 and 193). The author list and affiliations have been amended to address these omissions in both the HTML and PDF versions.

We introduce a nanoengineered nonlinear metasurface based optical element that acts as an emitting Fresnel zone plate of terahertz (THz) waves. We show that the nonlinear zone plate generates broadband THz radiation and focuses each generated frequency on a different focal point along the optical axis. Therefore, a narrow beam waist and spectral selectivity of both the bandwidth and central frequency are achieved. Furthermore, we measure and analyze the temporal structure of the focused THz electric field and show that it comprises of few cycles with an axially varying carrier frequency in agreement with the calculated dispersion of the zone plate. This demonstration of controlled emission and focusing of THz waves opens the door for the development of a wide variety of additional holographic metasurface-based THz emitters and can lead to the development of efficient, active, integrated, and ultracompact optical devices for the THz spectral region.

Fibromyalgia (FM) is a prevalent syndrome, characterised by chronic widespread pain, fatigue, and impaired sleep, that is challenging to diagnose and difficult to treat. The microbiomes of 77 women with FM and that of 79 control participants were compared using 16S rRNA gene amplification and whole-genome sequencing. When comparing FM patients with unrelated controls using differential abundance analysis, significant differences were revealed in several bacterial taxa. Variance in the composition of the microbiomes was explained by FM-related variables more than by any other innate or environmental variable and correlated with clinical indices of FM. In line with observed alteration in butyrate-metabolising species, targeted serum metabolite analysis verified differences in the serum levels of butyrate and propionate in FM patients. Using machine-learning algorithms, the microbiome composition alone allowed for the classification of patients and controls (receiver operating characteristic area under the curve 87.8%). To the best of our knowledge, this is the first demonstration of gut microbiome alteration in nonvisceral pain. This observation paves the way for further studies, elucidating the pathophysiology of FM, developing diagnostic aids and possibly allowing for new treatment modalities to be explored.

Ecological research heavily relies on coarse-gridded climate data based on standardized temperature measurements recorded at 2 m height in open landscapes. However, many organisms experience environmental conditions that differ substantially from those captured by these macroclimatic (i.e. free air) temperature grids. In forests, the tree canopy functions as a thermal insulator and buffers sub-canopy microclimatic conditions, thereby affecting biological and ecological processes. To improve the assessment of climatic conditions and climate-change-related impacts on forest-floor biodiversity and functioning, high-resolution temperature grids reflecting forest microclimates are thus urgently needed. Combining more than 1200 time series of in situ near-surface forest temperature with topographical, biological and macroclimatic variables in a machine learning model, we predicted the mean monthly offset between sub-canopy temperature at 15 cm above the surface and free-air temperature over the period 2000-2020 at a spatial resolution of 25 m across Europe. This offset was used to evaluate the difference between microclimate and macroclimate across space and seasons and finally enabled us to calculate mean annual and monthly temperatures for European forest understories. We found that sub-canopy air temperatures differ substantially from free-air temperatures, being on average 2.1°C (standard deviation ± 1.6°C) lower in summer and 2.0°C higher (±0.7°C) in winter across Europe. Additionally, our high-resolution maps expose considerable microclimatic variation within landscapes, not captured by the gridded macroclimatic products. The provided forest sub-canopy temperature maps will enable future research to model below-canopy biological processes and patterns, as well as species distributions more accurately. ispartof: GLOBAL CHANGE BIOLOGY vol:27 issue:23 pages:6307-6319 ispartof: location:England status: published

Fibromyalgia (FM) is a condition of chronic widespread pain (CWP) that can occur throughout the life cycle and is likely underrecognized in older patients. FM is associated with considerable suffering and reduction in quality of life and may occur as a unique condition, but in older patients is most likely to be associated with another medical illness. Understood mechanistically to be a sensitization of the nervous system, recently identified as nociplastic pain, FM is accepted as a valid medical illness that requires a positive diagnosis and directed treatments. The cornerstone of treatments for FM are nonpharmacologic interventions, with the understanding that medications provide only modest benefit for most patients, and with particular concern about adverse effects in older patients. If FM is not recognized, treatments may be misdirected to the other medical condition, with failure to address FM symptoms, leading to overall poor outcome. In contrast, new complaints in older patients should not immediately be attributed to FM, and physicians should be vigilant to ensure that onset of a new illness is not ignored. As FM is most often a lifelong condition, patients should be encouraged to identify their own personal strategies that can attenuate symptoms, especially when symptoms flare. Continued life participation should be the outcome goal.

IntroductionAn Ideal battery of testing for function would be inexpensive, easily administered, standardized and validated for multiple health issues. This would also be sensitive to change over time and able to extrapolate avocational and vocational tasks. The data collection exercise for this study included both subjective and objective measures which include the Short Form Health Survey 12 (SF-12), the 2 minute walk test (2MWT) and a newly developed upper extremity strength/conditioning activity called the Elevation and Movement Lift test (EMLi).MethodsA convenience sample of 102 patients with chronic pain. They were seen in the Canadian Forces Health Services Unit (CFHSU (O)) Physiatry Clinic between January-September 2019 and were asked to complete the data intake protocol. This included: completing a questionnaire with the Numeric Rating Pain Scale (NRS) covering the previous 7 days, the SF-12, and completed the 2 MWT and EMLi.ResultsFor the 2MWT heart rate, perceived exertion and number of steps were all increased for patients with chronic pain compared to the control group. There was no difference noted between patients with upper/lower body pain. In patients with chronic pain SF-12 physical function score negatively correlated with perceived exertion but not performance. As for the EMLI test, all groups had similar perceived exertion and heart rate outcomes but a reduced performance was noted with the upper extremity group.DiscussionFor the 2MWT, the individual’s performance related to effort and not their pain state, PE and SF-12. This suggests a higher capacity for walking then the patients realise. As for the EMLi, individual’s performance was poorer for same level of effort. This correlates to their perceived function as seen on the SF-12 which might measure pain related dysfunction.ConclusionThe 2MWT performance was effort dependent and not correlated with perceived abilities. Therefore it can be used to challenge patient performance. EMLi performance correlated with perception and upper extremity pain. This could be used to set clinical training targets and monitor each individual’s progress.