Myelin-reactive B cells exacerbate CD4+ T cell-driven CNS autoimmunity in an IL-23-dependent manner.

B cells and T cells collaborate in multiple sclerosis (MS) pathogenesis. IgH[MOG] mice possess a B cell repertoire skewed to recognize myelin oligodendrocyte glycoprotein (MOG). Here, we show that upon immunization with the T cell-obligate autoantigen, MOG[35-55], IgH[MOG] mice develop rapid and exacerbated experimental autoimmune encephalomyelitis (EAE) relative to wildtype (WT) counterparts, characterized by aggregation of T and B cells in the IgH[MOG] meninges and by CD4+ T helper 17 (Th17) cells in the CNS. Production of the Th17 maintenance factor IL-23 is observed from IgH[MOG] CNS-infiltrating and meningeal B cells, and in vivo blockade of IL-23p19 attenuates disease severity in IgH[MOG] mice. In the CNS parenchyma and dura mater of IgH[MOG] mice, we observe an increased frequency of CD4+PD-1+CXCR5- T cells that share numerous characteristics with the recently described T peripheral helper (Tph) cell subset. Further, CNS-infiltrating B and Tph cells from IgH[MOG] mice show increased reactive oxygen species (ROS) production. Meningeal inflammation, Tph-like cell accumulation in the CNS and B/Tph cell production of ROS were all reduced upon p19 blockade. Altogether, MOG-specific B cells promote autoimmune inflammation of the CNS parenchyma and meninges in an IL-23-dependent manner.

Insights into physical activity promotion among Australian chiropractors: a cross-sectional survey.

BACKGROUND: Despite the well-known benefits of physical activity, physical inactivity is presently a global health pandemic. Allied healthcare providers, such as chiropractors, knowingly recognise the importance of physical activity and are prepared to routinely discuss and/or counsel patients on this topic; however, little is known about Australian chiropractors in the physical activity setting. Our aim was to explore and identify factors associated with physical activity promotion among Australian chiropractors, including their knowledge of the physical activity and sedentary behaviour guidelines and their own levels of physical activity. METHODS: From February to May 2021, a convenience sample of Australian chiropractors completed an online survey. Items assessed by Likert scale included: physical activity promotion frequency, with the type, quantity, barriers, perceptions, and feasibility. We asked questions about their familiarity with, and knowledge of, Australian Physical Activity and Sedentary Behaviour Guidelines, chiropractors' own physical activity, and whether the chiropractors met activity guidelines. Survey responses were descriptively reported. Univariable logistic regression models explored factors explaining frequent physical activity promotion. RESULTS: Of 217 respondents, 64% reported that they frequently (≥ 70%) recommended a more physically active lifestyle. Only 15% often performed pre-exercise screening, 73% frequently prescribed resistance exercise, 19% reported time as the most frequent barrier, while 37% reported being not at all familiar with the guidelines. Univariable logistic regression models found male chiropractors were more likely to promote physical activity, [odds ratio (OR) = 2.33; 95% confidence interval (CI): 1.32-4.12)], while chiropractors who frequently treat children 0-3 years (OR = 0.5; 95% CI: 0.28-0.87), children 4-18 years (OR = 0.42; 95% CI: 0.21-0.86), and pregnant women (OR = 0.5; 95% CI: 0.26-0.94) were less likely. Chiropractors were more likely to promote physical activity if they were familiar with the activity guidelines (OR = 2.9; 95% CI: 1.32-6.41), were confident promoting (OR = 11.6; 95% CI: 1.37-98.71) and prescribing physical activity programs (OR = 4.5; 95% CI: 2.03-9.99). CONCLUSION: Most chiropractors confidently and regularly integrate physical activity into practice. Yet, despite acknowledging its importance, one third of chiropractors reported poor knowledge of the Physical Activity and Sedentary Behaviour Guidelines. Identifying barriers to the awareness, and implementation of physical activity guidelines should be further explored within chiropractic clinical settings.

Transcranial magnetic stimulation enhances the specificity of multiple sclerosis diagnostic criteria: a critical narrative review.

Background: Multiple sclerosis (MS) is an immune-mediated neurodegenerative disease that involves attacks of inflammatory demyelination and axonal damage, with variable but continuous disability accumulation. Transcranial magnetic stimulation (TMS) is a noninvasive method to characterize conduction loss and axonal damage in the corticospinal tract. TMS as a technique provides indices of corticospinal tract function that may serve as putative MS biomarkers. To date, no reviews have directly addressed the diagnostic performance of TMS in MS. The authors aimed to conduct a critical narrative review on the diagnostic performance of TMS in MS. Methods: The authors searched the Embase, PubMed, Scopus, and Web of Science databases for studies that reported the sensitivity and/or specificity of any reported TMS technique compared to established clinical MS diagnostic criteria. Studies were summarized and critically appraised for their quality and validity. Results: Seventeen of 1,073 records were included for data extraction and critical appraisal. Markers of demyelination and axonal damage-most notably, central motor conduction time (CMCT)-were specific, but not sensitive, for MS. Thirteen (76%), two (12%), and two (12%) studies exhibited high, unclear, and low risk of bias, respectively. No study demonstrated validity for TMS techniques as diagnostic biomarkers in MS. Conclusions: CMCT has the potential to: (1) enhance the specificity of clinical MS diagnostic criteria by "ruling in" true-positives, or (2) revise a diagnosis from relapsing to progressive forms of MS. However, there is presently insufficient high-quality evidence to recommend any TMS technique in the diagnostic algorithm for MS.

Body weight, behaviours of concern, and social contact in adults and adolescents with Prader-Willi syndrome in full-time care services: Findings from pooled international archival data.

BACKGROUND: Prader-Willi syndrome (PWS) is a complex genetic neurodevelopmental condition characterised by a range of debilitating and lifelong symptoms. The many physical and behavioural challenges that arise with adults with PWS often necessitate full-time (i.e., 24-hour) professional care support. However, despite the fact that many clinicians regard full-time PWS-specific care to represent best practice, relatively few studies have directly examined the benefits of such services. The purpose of this paper is to use archival data to investigate the impact of full-time care services on people with PWS, and to assemble a large statistical dataset on which robust analyses of improvements in weight, BMI, and behavioural outcomes can be based. METHODS: Information collated by the International PWS Organisation (IPWSO), an international non-profit membership organisation supporting national PWS associations around the world, was combined into a single anonymised dataset for statistical analysis. Data were supplied by service-providers from several countries who provide full-time support to people with PWS. The dataset included details on the specific services provided, basic demographic information on service recipients, including weight, body mass index (BMI), and observational records relating to behaviours of concern (BOC; consisting of temper outbursts, skin-picking, egocentrism, inflexibility, and striving for dominance). RESULTS: A total of 193 people with PWS (ranging in age from < 10 yrs to > 50 yrs; 93% of whom were > 18 yrs), residing in 11 services across 6 countries, were represented in the dataset. On average, people with PWS showed significant reductions in weight and BMI after joining a full-time care service, with improvements within one year of entering, which were cumulative over time and independent of age or initial weight at entry. Similar cumulative improvements over time were seen for BOC within one year and were unrelated to age or severity of BOC at entry. The degree to which services are specialised for residents with PWS appeared to confer particular benefits, with people living in PWS-exclusive services showing the greatest improvements in weight, BMI, and BOC. Reductions in BOC were associated with greater, rather than less, social contact, suggesting that these improvements were not achieved at the expense of broader freedoms, such as the opportunity to meet with families and friends. CONCLUSIONS: We conclude that full-time care services have a high likelihood of enhancing the lives of people with PWS within one year with long-lasting benefits, especially if those services are exclusive and specialised around the particular needs of PWS.

Apically localized PANX1 impacts neuroepithelial expansion in human cerebral organoids.

Dysfunctional paracrine signaling through Pannexin 1 (PANX1) channels is linked to several adult neurological pathologies and emerging evidence suggests that PANX1 plays an important role in human brain development. It remains unclear how early PANX1 influences brain development, or how loss of PANX1 alters the developing human brain. Using a cerebral organoid model of early human brain development, we find that PANX1 is expressed at all stages of organoid development from neural induction through to neuroepithelial expansion and maturation. Interestingly, PANX1 cellular distribution and subcellular localization changes dramatically throughout cerebral organoid development. During neural induction, PANX1 becomes concentrated at the apical membrane domain of neural rosettes where it co-localizes with several apical membrane adhesion molecules. During neuroepithelial expansion, PANX1-/- organoids are significantly smaller than control and exhibit significant gene expression changes related to cell adhesion, WNT signaling and non-coding RNAs. As cerebral organoids mature, PANX1 expression is significantly upregulated and is primarily localized to neuronal populations outside of the ventricular-like zones. Ultimately, PANX1 protein can be detected in all layers of a 21-22 post conception week human fetal cerebral cortex. Together, these results show that PANX1 is dynamically expressed by numerous cell types throughout embryonic and early fetal stages of human corticogenesis and loss of PANX1 compromises neuroepithelial expansion due to dysregulation of cell-cell and cell-matrix adhesion, perturbed intracellular signaling, and changes to gene regulation.

Cross-talk between B cells, microglia and macrophages, and implications to central nervous system compartmentalized inflammation and progressive multiple sclerosis.

BACKGROUND: B cells can be enriched within meningeal immune-cell aggregates of multiple sclerosis (MS) patients, adjacent to subpial cortical demyelinating lesions now recognized as important contributors to progressive disease. This subpial demyelination is notable for a 'surface-in' gradient of neuronal loss and microglial activation, potentially reflecting the effects of soluble factors secreted into the CSF. We previously demonstrated that MS B-cell secreted products are toxic to oligodendrocytes and neurons. The potential for B-cell-myeloid cell interactions to propagate progressive MS is of considerable interest. METHODS: Secreted products of MS-implicated pro-inflammatory effector B cells or IL-10-expressing B cells with regulatory potential were applied to human brain-derived microglia or monocyte-derived macrophages, with subsequent assessment of myeloid phenotype and function through measurement of their expression of pro-inflammatory, anti-inflammatory and homeostatic/quiescent molecules, and phagocytosis (using flow cytometry, ELISA and fluorescently-labeled myelin). Effects of secreted products of differentially activated microglia on B-cell survival and activation were further studied. FINDINGS: Secreted products of MS-implicated pro-inflammatory B cells (but not IL-10 expressing B cells) substantially induce pro-inflammatory cytokine (IL-12, IL-6, TNFα) expression by both human microglia and macrophage (in a GM-CSF dependent manner), while down-regulating their expression of IL-10 and of quiescence-associated molecules, and suppressing their myelin phagocytosis. In contrast, secreted products of IL-10 expressing B cells upregulate both human microglia and macrophage expression of quiescence-associated molecules and enhance their myelin phagocytosis. Secreted factors from pro-inflammatory microglia enhance B-cell activation. INTERPRETATION: Potential cross-talk between disease-relevant human B-cell subsets and both resident CNS microglia and infiltrating macrophages may propagate CNS-compartmentalized inflammation and injury associated with MS disease progression. These interaction represents an attractive therapeutic target for agents such as Bruton's tyrosine kinase inhibitors (BTKi) that modulate responses of both B cells and myeloid cells. FUNDING: Stated in Acknowledgments section of manuscript.

Head and Neck Squamous Cell Carcinoma Biopsies Maintained Ex Vivo on a Perfusion Device Show Gene Changes with Time and Clinically Relevant Doses of Irradiation.

Advancements in 3-Dimensional (3D) culture models for studying disease have increased significantly over the last two decades, but fully understanding how these models represent in vivo still requires further investigation. The current study investigated differences in gene expression between a baseline sample and that maintained on a tissue-on-chip perfusion device for up to 96 h, with and without clinically-relevant doses of irradiation, to allow differentiation of model and treatment effects. Tumour tissue samples from 7 Head and Neck Squamous Cell Carcinomas (HNSCC) patients were sub-divided and either fixed immediately upon excision or maintained in a tissue-on-chip device for 48 and 96 h, with or without 2 Gray (Gy) or 10 Gy irradiation. Gene expression was measured using an nCounter® PanCancer Progression Panel. Differentially expressed genes between pre- and post-ex vivo culture, and control and irradiated samples were identified using nSolver software (version 4.0). The secretome from the tumour-on-chip was analysed for the presence of cytokines using a Proteome Profiler™ platform. Significant numbers of genes both increased (n = 6 and 64) and decreased (n = 18 and 58) in expression in the tissue maintained on-chip for 48 and 96 h, respectively, compared to fresh tissue; however, the irradiation schedule chosen did not induce significant changes in gene expression or cytokine secretion. Although HNSCC tissue maintained ex vivo shows a decrease in a large proportion of altered genes, 25% and 53% (48 and 96 h) do show increased expression, suggesting that the tissue remains functional. Irradiation of tumour tissue-on-chip needs to be conducted for longer time periods for specific gene changes to be observed, but we have shown, for the first time, the feasibility of using this perfusion platform for studying the genomic response of HNSCC tissue biopsies.

Translocator protein is a marker of activated microglia in rodent models but not human neurodegenerative diseases.

Microglial activation plays central roles in neuroinflammatory and neurodegenerative diseases. Positron emission tomography (PET) targeting 18 kDa Translocator Protein (TSPO) is widely used for localising inflammation in vivo, but its quantitative interpretation remains uncertain. We show that TSPO expression increases in activated microglia in mouse brain disease models but does not change in a non-human primate disease model or in common neurodegenerative and neuroinflammatory human diseases. We describe genetic divergence in the TSPO gene promoter, consistent with the hypothesis that the increase in TSPO expression in activated myeloid cells depends on the transcription factor AP1 and is unique to a subset of rodent species within the Muroidea superfamily. Finally, we identify LCP2 and TFEC as potential markers of microglial activation in humans. These data emphasise that TSPO expression in human myeloid cells is related to different phenomena than in mice, and that TSPO-PET signals in humans reflect the density of inflammatory cells rather than activation state.

CXCL10 Is Associated with Increased Cerebrospinal Fluid Immune Cell Infiltration and Disease Duration in Multiple Sclerosis.

BACKGROUND: Cerebrospinal fluid (CSF) is an important sampling site for putative biomarkers and contains immune cells. CXCL10 is a multiple sclerosis (MS)-relevant chemokine that is present in the injured central nervous system and recruits CXCR3+ immune cells toward injured tissues. OBJECTIVE: Perform a comprehensive evaluation to determine a potential relationship between CXCL10 and various immune cell subsets in the CNS of MS and control cases. METHODS: In MS and control cases, CXCL10 was measured in the CSF and plasma by ELISA. Immune cells within both the CSF and peripheral blood were quantified by flow cytometry. RESULTS: Compared to non-inflammatory neurological disease (NIND) cases, MS cases had significantly higher CXCL10 in CSF (p = 0.021); CXCL10 was also correlated with total cell numbers in CSF (p = 0.04) and T cell infiltrates (CD3+, p = 0.01; CD4+, p = 0.01; CD8+, p = 0.02); expression of CXCR3 on peripheral immune cell subsets was not associated with CSF CXCL10. CONCLUSIONS: Elevated levels of CXCL10 in the CSF of MS cases are associated with increased T cells but appear to be independent of peripheral CXCR3 expression. These results support the importance of elevated CXCL10 in MS and suggest the presence of an alternative mechanism of CXCL10 outside of solely influencing immune cell trafficking.

A comparison of physical image quality of two hologic digital mammography systems that utilise linear and 2D anti-scatter grids.

Objective. Full-field digital mammography (FFDM) systems manufactured by Hologic that utilise either a 2D or linear anti-scatter grid have recently been installed in our clinic. The manufacturer advise that for matched dose, both grids deliver comparable image quality. The aim of this study was to test the manufacturer's claim using advanced physical image quality metrics and to inform whether the different grids are indeed dose neutral.Approach. Effective detective quantum efficiency (eDQE), effective noise equivalent quanta (eNEQ) and effective dose efficiency (eDE) were measured on a Hologic Dimensions (2D grid) and a Hologic 3Dimensions (linear grid) FFDM system, both calibrated at installation to provide matched threshold contrast, according to the EUREF protocol. eDQE, eNEQ and eDE were calculated and compared using 2, 4, 6 and 7 cm thicknesses of poly (methyl methacrylate) (PMMA) to simulate a clinically appropriate range of breast thicknesses. The beam qualities (target/filter and kilovoltage) chosen were identical between the two systems.Main results. All image quality metrics investigated show that the 2D grid outperforms the linear grid across all spatial frequencies. Furthermore, mean glandular dose (MGD) must be increased by up to 38% on those units that utilise the linear grid if eNEQ is to be matched, although MGD to the standard breast remains within NHSBSP tolerance and below the UK diagnostic reference level. The gradient and shape of each curve was the same irrespective of which grid was used, suggesting that subtle lesions (low frequency information) and micro-calcifications (high frequency information) will be imaged just as efficiently with a linear or 2D grid.Significance. If image quality is to be matched between those units utilising 2D and linear grids, dose must be increased on the latter. This information will be useful to the medical physicist tasked with the optimisation and standardisation of Hologic FFDM units.

Evaluation of the dataset quality in gamma passing rate predictions using machine learning methods.

OBJECTIVE: Gamma passing rate (GPR) predictions using machine learning methods have been explored for treatment verification of radiotherapy plans. However, these methods presented datasets with unbalanced number of plans having different treatment conditions (heterogeneous datasets), such as anatomical sites or dose per fractions, leading to lower model interpretability and prediction performance. METHODS: We investigated the impact of the dataset composition on GPR binary classification (pass/fail) using random forest (RF), XG-boost, and neural network (NN) models. 945 plans were used to create one reference dataset (randomly assembled) and 24 customized datasets that considered four heterogeneity factors independently (anatomical region, number of arcs, dose per fraction, and treatment unit). 309 predictor features were extracted and calculated from plan parameters, modulation complexity metrics, and radiomic analysis (leave-trajectory maps, 3D dose distributions, and portal dosimetry images). The models' performances were measured using the area under the curve from the receiver operating characteristic (ROC-AUC). RESULTS: Radiomics features for reference models increased ROC-AUC values up to 13%, 15%, and 5% for RF, XG-Boost, and NN, respectively. The datasets with higher heterogeneous conditions presented the lower ROC-AUC values (RF: 0.72 ± 0.11, XG-Boost: 0.67 ± 0.1, NN: 0.89 ± 0.05) compared to models with less heterogeneous treatment conditions (RF: 0.88 ± 0.06, XG-Boost: 0.89 ± 0.07, NN: 0.98 ± 0.01). The ten most important features for each heterogeneity dataset group demonstrated their correlation with the treatments' physical aspects and GPR prediction. CONCLUSION: Improvements in data generalization and model performances can be associated with datasets having similar treatment conditions. This analysis might be implemented to evaluate the dataset quality and model consistency of further ML applications in radiotherapy. ADVANCES IN KNOWLEDGE: Dataset heterogeneities decrease ML model performance and reliability.

TAAR1 Regulates Purinergic-induced TNF Secretion from Peripheral, But Not CNS-resident, Macrophages.

Trace amine-associated receptor 1 (TAAR1) is an established neuroregulatory G protein-coupled receptor with recent studies suggesting additional functions related to immunomodulation. Our lab has previously investigated TAAR1 expression within cells of the innate immune system and herein we aim to further elucidate TAAR1 function in both peripherally-derived and CNS-resident macrophages. The selective TAAR1 agonist RO5256390 was used in combination with common damage associated molecular patterns (ATP and ADP) to observe the effect of TAAR1 agonism on modulating cytokine secretion and metabolic profiles. In mouse bone-marrow derived macrophages, TAAR1 agonism inhibited TNF secretion following ATP stimulation, which appeared to be downstream of an associated pro-inflammatory shift in metabolic profile and transcriptional regulation of TNF synthesis. In contrast, TAAR1 agonism had no effect on ADP-induced TNF and IL-6 secretion in mouse microglia in either the presence or absence of astrocytes. In summary, we report a novel interaction between TAAR1 and purinergic signaling in peripherally-derived, but not CNS-resident, macrophages. These findings provide the first evidence of trace aminergic and purinergic crosstalk, and support the potential for TAAR1 as a novel therapeutic target in inflammatory disorders.

Machine learning-based predictions of gamma passing rates for virtual specific-plan verification based on modulation maps, monitor unit profiles, and composite dose images.

Machine learning (ML) methods have been implemented in radiotherapy to aid virtual specific-plan verification protocols, predicting gamma passing rates (GPR) based on calculated modulation complexity metrics because of their direct relation to dose deliverability. Nevertheless, these metrics might not comprehensively represent the modulation complexity, and automatically extracted features from alternative predictors associated with modulation complexity are needed. For this reason, three convolutional neural networks (CNN) based models were trained to predict GPR values (regression and classification), using respectively three predictors: (1) the modulation maps (MM) from the multi-leaf collimator, (2) the relative monitor units per control point profile (MUcp), and (3) the composite dose image (CDI) used for portal dosimetry, from 1024 anonymized prostate plans. The models' performance was assessed for classification and regression by the area under the receiver operator characteristic curve (AUC_ROC) and Spearman's correlation coefficient (r). Finally, four hybrid models were designed using all possible combinations of the three predictors. The prediction performance for the CNN-models using single predictors (MM, MUcp, and CDI) were AUC_ROC = 0.84 ± 0.03, 0.77 ± 0.07, 0.75 ± 0.04, andr= 0.6, 0.5, 0.7. Contrastingly, the hybrid models (MM + MUcp, MM + CDI, MUcp+CDI, MM + MUcp+CDI) performance were AUC_ROC = 0.94 ± 0.03, 0.85 ± 0.06, 0.89 ± 0.06, 0.91 ± 0.03, andr= 0.7, 0.5, 0.6, 0.7. The MP, MUcp, and CDI are suitable predictors for dose deliverability models implementing ML methods. Additionally, hybrid models are susceptible to improving their prediction performance, including two or more input predictors.

Does the use of the Bruton Tyrosine Kinase inhibitors and the c-kit inhibitor masitinib result in clinically significant outcomes among patients with various forms of multiple sclerosis?

Multiple sclerosis (MS) is an immune-mediated demyelinating disease of the central nervous system accompanied by chronic inflammation, axonal loss, and neurodegeneration. Traditionally, MS has been thought of as a T-cell mediated disease, but research over the past decade has demonstrated the importance of B cells in both acute demyelination and disease progression. The highly selective irreversible Bruton Tyrosine Kinase (BTK) inhibitors evobrutinib, tolebrutinib, and orelabrutinib, and the reversible BTK inhibitor fenebrutinib, all target B-cell activation and aspects of innate immunity, including macrophage and microglia biology. The c-KIT inhibitor masitinib mitigates neuroinflammation by controlling the survival, migration, and degranulation of mast cells, leading to the inhibition of proinflammatory and vasoactive molecular cascades that result from mast cell activation. This article will review and critically appraise the ongoing clinical trials of two classes of receptor tyrosine kinase inhibitors that are emerging as potential medical treatments for the varying subtypes of MS: BTK inhibitors and c-KIT inhibitors. Specifically, this review will attempt to answer whether BTK inhibitors have measurable positive clinical effects on patients with RRMS, SPMS with relapses, relapse-free SPMS, and PPMS through their effect on MRI T1 lesions; annualized relapse rate; EDSS scale; MSFC score; and time to onset of composite 12-week confirmed disability progression. Additionally, this review will examine the literature to determine if masitinib has positive clinical effects on patients with PPMS or relapse-free SPMS through its effect on EDSS or MSFC scores.

Research Priorities of the Australian Chiropractic Profession: A Cross-Sectional Survey of Academics and Practitioners.

OBJECTIVE: The purpose of this study was to explore the research priorities of Australian practicing chiropractors and academics across a set of research domains to determine the agreement or disagreement based on these domains. METHODS: We conducted a pilot-tested online survey focusing on the following 5 principal research domains: basic science, conditions (disorders chiropractors may encounter), patient subgroups, clinical interventions, and practice and public health/health services. Responses were sought regarding support for funding research scholarships, practice-based research networks, scientific conferences/symposia, journals, and existing research agendas. Data were collected (February 19 to May 24, 2019) from a sample of chiropractic academics (n1 = 33) representing 4 Australian programs and practicing chiropractors (n2 = 340). Collected data were ranked and analyzed to determine agreement across domains and items. RESULTS: There was agreement between the 2 groups across the majority (>90%) of domain items. The closest agreement and highest rankings were achieved for the "clinical interventions and practice" and "conditions" domains. Disagreement was observed within specific domain items, such as patient subgroups (infants), and for 1 intervention (chiropractic-specific techniques). Disagreement also occurred outside of the main domains, including research agenda support and funding. CONCLUSIONS: There was overall agreement between practicing chiropractors and academics across most research area domain items, which should help facilitate consensus-led development of any potential Australian Chiropractic research agenda. Disagreements across specific domain items, such as population subgroups, interventions, and funding require further investigation.

Investigating the NLRP3 inflammasome and its regulator miR-223-3p in multiple sclerosis and experimental demyelination.

Innate immune signaling pathways are essential mediators of inflammation and repair following myelin injury. Inflammasome activation has recently been implicated as a driver of myelin injury in multiple sclerosis (MS) and its animal models, although the regulation and contributions of inflammasome activation in the demyelinated central nervous system (CNS) are not completely understood. Herein, we investigated the NLRP3 (NBD-, LRR- and pyrin domain-containing protein 3) inflammasome and its endogenous regulator microRNA-223-3p within the demyelinated CNS in both MS and an animal model of focal demyelination. We observed that NLRP3 inflammasome components and microRNA-223-3p were upregulated at sites of myelin injury within activated macrophages and microglia. Both microRNA-223-3p and a small-molecule NLRP3 inhibitor, MCC950, suppressed inflammasome activation in macrophages and microglia in vitro; compared with microglia, macrophages were more prone to inflammasome activation in vitro. Finally, systemic delivery of MCC950 to mice following lysolecithin-induced demyelination resulted in a significant reduction in axonal injury within demyelinated lesions. In conclusion, we demonstrate that NLRP3 inflammasome activity by macrophages and microglia is a critical component of the inflammatory microenvironment following demyelination and represents a potential therapeutic target for inflammatory-mediated demyelinating diseases, including MS. Cover Image for this issue: https://doi.org/10.1111/jnc.15422.

The impact and public health response of chiropractors to the COVID-19 pandemic: a survey across four continents.

BACKGROUND: The unprecedented impact of COVID-19 on healthcare professionals has implications for healthcare delivery, including the public health guidance provided to patients. This study aims to assess the response and impact of COVID-19 on chiropractors internationally, and examines the public health response of chiropractors to the COVID-19 pandemic practising under a musculoskeletal spine-care versus subluxation-based care paradigm. METHODS: A survey was distributed to chiropractors in Australia, Canada, Denmark, Hong Kong, United Kingdom and United States (Oct. 2nd-Dec. 22nd, 2020) via professional bodies/publications, and social media. Questions were categorised into three domains: socio-demographic, public health response and business/financial impact. Multivariable logistic regression explored survey items associated with chiropractors practising under different self-reported paradigms. RESULTS: A total of 2061 chiropractors representing four global regions completed the survey. Our recruitment method did not allow the calculation of an accurate response rate. The vast majority initiated COVID-19 infection control changes within their practice setting, including increased disinfecting of treatment equipment (95%), frequent contact areas (94%) and increased hand hygiene (94%). While findings varied by region, most chiropractors (85%) indicated that they had implemented regulator advice on the use of personal protective equipment (PPE). Suspension of face-to-face patient care during the peak of the pandemic was reported by 49% of the participants with 26% implementing telehealth since the pandemic began. Chiropractors practising under a musculoskeletal spine-care paradigm were more likely to implement some/all regulator advice on patient PPE use (odds ratio [OR] = 3.25; 95% confidence interval [CI]: 1.57, 6.74) and practitioner PPE use (OR = 2.59; 95% CI 1.32, 5.08); trust COVID-19 public health information provided by government/World Health Organisation/chiropractic bodies (OR = 2.47; 95% CI 1.49, 4.10), and initiate patient telehealth in response to COVID-19 (OR = 1.46; 95% CI 1.02, 2.08) compared to those practising under a subluxation-based paradigm. CONCLUSIONS: Chiropractors who responded to our survey made substantial infectious control changes in response to COVID-19. However, there was regional variation in the implementation of the advised practitioner and patient use of PPE and limited overall use of telehealth consultations by chiropractors during COVID-19. Musculoskeletal spine-care chiropractors were more adaptive to certain COVID-19 public health changes within their practice setting than subluxation-based chiropractors.

Analysis of Plasma Using Flow Cytometry Reveals Increased Immune Cell-Derived Extracellular Vesicles in Untreated Relapsing-Remitting Multiple Sclerosis.

Extracellular vesicles (EVs) are secreted from cells under physiological and pathological conditions, and are found in biological fluids while displaying specific surface markers that are indicative of their cell of origin. EVs have emerged as important signaling entities that may serve as putative biomarkers for various neurological conditions, including multiple sclerosis (MS). The objective of this study was to measure and compare immune cell-derived EVs within human plasma between untreated RRMS patients and healthy controls. Using blood plasma and peripheral blood mononuclear cells (PBMCs) collected from RRMS patients and controls, PBMCs and EVs were stained and quantified by flow cytometry using antibodies against CD9, CD61, CD45, CD3, CD4, CD8, CD14, and CD19. While several immune cell-derived EVs, including CD3+, CD4+, CD8+, CD14+, and CD19+ were significantly increased in RRMS vs. controls, no differences in immune cell subsets were observed with the exception of increased circulating CD19+ cells in RRMS patients. Our study demonstrated that plasma-derived EVs secreted from T cells, B cells, and monocytes were elevated in untreated RRMS cases with low disability, despite very limited changes in circulating immune cells, and suggest the utility of circulating EVs as biomarkers in MS.

Predicting personalised and progressive adaptive dose escalation to gross tumour volume using knowledge-based planning models for inoperable advanced-stage non-small cell lung cancer patients treated with volumetric modulated arc therapy.

Objectives. Increased radiation doses could improve local control and overall survival of lung cancer patients, however, this could be challenging without exceeding organs at risk (OAR) dose constraints, especially for patients with advanced-stage disease. Increasing OAR doses could reduce the therapeutic ratio and quality of life. It is therefore important to investigate methods to increase the dose to target volume without exceeding OAR dose constraints.Methods. Gross tumour volume (GTV) was contoured on synthetic computerised tomography (sCT) datasets produced using the Velocity adaptive radiotherapy software for eleven patients. The fractions where GTV volume decreased compared to that prior to radiotherapy (reference plan) were considered for personalised progressive dose escalation. The dose to the adapted GTV (GTVAdaptive) was increased until OAR doses were affected (as compared to the original clinical plan). Planning target volume (PTV) coverage was maintained for all plans. Doses were also escalated to the reference plan (GTVClinical) using the same method. Adapted, dose-escalated, plans were combined to estimate accumulated dose, D99(dose to 99%) of GTVAdapted, PTV D99and OAR doses and compared with those in the original clinical plans. Knowledge-based planning (KBP) model was developed to predict D99of the adapted GTV with OAR doses and PTV coverage kept similar to the original clinical plans; prediction accuracy and model verification were performed using further data sets.Results. Compared to the original clinical plan, the dose to GTV was significantly increased without exceeding OAR doses. Adaptive dose-escalation increased the average D99to GTVAdaptiveby 15.1Gy and 8.7Gy compared to the clinical plans. The KBP models were verified and demonstrated prediction accuracy of 0.4% and 0.7% respectively.Conclusion. Progressive adaptive dose escalation can significantly increase the dose to GTV without increasing OAR doses or compromising the dose to microscopic disease. This may increase overall survival without increasing toxicities.