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The third International Scientific Tendinopathy Symposium - New Approaches to Tendon Therapeutics - is being held in St Hilda's College, Oxford, on Friday 5 and Saturday 6 September. The event brings together an unprecedented mix of excellent basic and translational science and the finest clinical expertise.
Auditory cues modulate the short timescale dynamics of STN activity during stepping in Parkinson's disease.
BACKGROUND: Gait impairment has a major impact on quality of life in patients with Parkinson's disease (PD). It is believed that basal ganglia oscillatory activity at β frequencies (15-30 Hz) may contribute to gait impairment, but the precise dynamics of this oscillatory activity during gait remain unclear. Additionally, auditory cues are known to lead to improvements in gait kinematics in PD. If the neurophysiological mechanisms of this cueing effect were better understood they could be leveraged to treat gait impairments using adaptive Deep Brain Stimulation (aDBS) technologies. OBJECTIVE: We aimed to characterize the dynamics of subthalamic nucleus (STN) oscillatory activity during stepping movements in PD and to establish the neurophysiological mechanisms by which auditory cues modulate gait. METHODS: We studied STN local field potentials (LFPs) in eight PD patients while they performed stepping movements. Hidden Markov Models (HMMs) were used to discover transient states of spectral activity that occurred during stepping with and without auditory cues. RESULTS: The occurrence of low and high β bursts was suppressed during and after auditory cues. This manifested as a decrease in their fractional occupancy and state lifetimes. Interestingly, α transients showed the opposite effect, with fractional occupancy and state lifetimes increasing during and after auditory cues. CONCLUSIONS: We show that STN oscillatory activity in the α and β frequency bands are differentially modulated by gait-promoting oscillatory cues. These findings suggest that the enhancement of α rhythms may be an approach for ameliorating gait impairments in PD.
Perinatal outcomes associated with pre-exposure prophylaxis for HIV prevention during pregnancy: a systematic review and meta-analysis
Background: The World Health Organization (WHO) recommends tenofovir disoproxil fumarate (TDF)-based oral pre-exposure prophylaxis (PrEP), the dapivirine vaginal ring, and long-acting intramuscular injectable cabotegravir (CAB-LA) for HIV prevention in populations at substantial risk of HIV infection. Pregnancy is a period of elevated risk of maternal HIV infection and transmission to the infant. This systematic review and meta-analysis assessed the risk of adverse perinatal outcomes among HIV-negative pregnant women with exposure to any PrEP modality. Methods: We conducted a systematic review by searching Medline, EMBASE, CINAHL, Global Health, the Cochrane Library, WHO ICTR, ISRCTN, PACTR, and ClinicalTrials.gov for studies published between 1 January 2000 and 29 August 2023. We included studies reporting on the association of antenatal exposure to any PrEP modality with 13 perinatal outcomes: preterm birth (PTB), very PTB, spontaneous PTB, spontaneous very PTB, low birthweight (LBW), very LBW, term LBW, preterm LBW, small for gestational age (SGA), very SGA, miscarriage, stillbirth, or neonatal death (NND). Quality assessments of included studies were performed. Fixed-effect meta-analyses were conducted to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs). The protocol is registered with PROSPERO, CRD42022339825. Findings: Of 18,598 citations identified, 13 studies (eight randomised controlled trials (RCTs) and five cohort studies), assessing 8712 pregnant women in Africa, were included. Oral PrEP, compared to no PrEP, was not associated with PTB in meta-analyses of six RCTs (OR 0.73, 95% CI 0.43–1.26; I2 = 0.0%) or five unadjusted cohort studies (OR 0.84, 95% CI 0.69–1.03; I2 = 0.0%), but was associated with a reduced risk of PTB in three adjusted cohort studies (aOR 0.67; 95% CI 0.52–0.88, I2 = 0.0%). There was no association of oral PrEP with LBW, vLBW, SGA, or NND, compared to no PrEP. There was no association with PTB when oral TDF/emtricitabine (FTC) PrEP, oral TDF PrEP, and tenofovir vaginal gel were compared to each other. There was no association of the dapivirine vaginal ring with PTB or NND, compared to placebo or oral TDF/FTC PrEP. We found no data on CAB-LA. Interpretation: We found no evidence of adverse perinatal outcomes associated with PrEP exposure during pregnancy. Our findings support the WHO recommendation to provide oral PrEP to women of reproductive age and pregnant women. More data is needed to assess the safety of all PrEP modalities in pregnancy. Funding: None.
Multi-omics analysis reveals COVID-19 vaccine induced attenuation of inflammatory responses during breakthrough disease.
The immune mechanisms mediating COVID-19 vaccine attenuation of COVID-19 remain undescribed. We conducted comprehensive analyses detailing immune responses to SARS-CoV-2 virus in blood post-vaccination with ChAdOx1 nCoV-19 or a placebo. Samples from randomised placebo-controlled trials (NCT04324606 and NCT04400838) were taken at baseline, onset of COVID-19-like symptoms, and 7 days later, confirming COVID-19 using nucleic amplification test (NAAT test) via real-time PCR (RT-PCR). Serum cytokines were measured with multiplexed immunoassays. The transcriptome was analysed with long, short and small RNA sequencing. We found attenuation of RNA inflammatory signatures in ChAdOx1 nCoV-19 compared with placebo vaccinees and reduced levels of serum proteins associated with COVID-19 severity. KREMEN1, a putative alternative SARS-CoV-2 receptor, was downregulated in placebo compared with ChAdOx1 nCoV-19 vaccinees. Vaccination ameliorates reductions in cell counts across leukocyte populations and platelets noted at COVID-19 onset, without inducing potentially deleterious Th2-skewed immune responses. Multi-omics integration links a global reduction in miRNA expression at COVID-19 onset to increased pro-inflammatory responses at the mRNA level. This study reveals insights into the role of COVID-19 vaccines in mitigating disease severity by abrogating pro-inflammatory responses associated with severe COVID-19, affirming vaccine-mediated benefit in breakthrough infection, and highlighting the importance of clinically relevant endpoints in vaccine evaluation.
Using evidence-based co-design to develop a hybrid delivered exercise intervention that aims to increase confidence to exercise in people with haemophilia.
INTRODUCTION: Due to advances in treatments, people with haemophilia (PWH) are living longer. They are not as active as the general population due to joint damage and lack confidence to be active due to concerns about further bleeds and pain. There is a need to facilitate healthy aging through promotion of physical activity (PA) and exercise. Changing patient beliefs and increasing physical literacy and confidence to move are thought to be key to helping PWH become more active. AIM: This paper describes the development of an exercise and behaviour change intervention to improve confidence to exercise in PWH. METHODS: The 4-stage Medical Research Council framework for complex intervention development was used. RESULTS: Stakeholders included 17 PWH and 7 physiotherapists working in haemophilia. Seven online focus group meetings were held. The final intervention is a hybrid 12-week physiotherapist led progressive exercise programme. Classes are 45 min including Pilates, High intensity interval training and balance elements, together with discussion sessions focusing on PA recommendations, the types and benefits of different exercise styles and the effects of PA, together with the effects of aging for PWH. The COM-B model of behaviour change was used to develop the intervention. CONCLUSION: Co-design helps to produce an intervention that understands the stakeholders needs. Through this process the intervention developed to incorporate not only increasing PA but also confidence to exercise. The use of behaviour change theory identified the behaviour techniques included in the intervention and aims to increase physical literacy in this population.
[Guidelines for clinical trial protocols for interventions involving artificial intelligence: the SPIRIT-AI extensionDiretrizes para protocolos de ensaios clínicos com intervenções que utilizam inteligência artificial: a extensão SPIRIT-AI].
The SPIRIT 2013 statement aims to improve the completeness of clinical trial protocol reporting by providing evidence-based recommendations for the minimum set of items to be addressed. This guidance has been instrumental in promoting transparent evaluation of new interventions. More recently, there has been a growing recognition that interventions involving artificial intelligence (AI) need to undergo rigorous, prospective evaluation to demonstrate their impact on health outcomes. The SPIRIT-AI (Standard Protocol Items: Recommendations for Interventional Trials-Artificial Intelligence) extension is a new reporting guideline for clinical trial protocols evaluating interventions with an AI component. It was developed in parallel with its companion statement for trial reports: CONSORT-AI (Consolidated Standards of Reporting Trials-Artificial Intelligence). Both guidelines were developed through a staged consensus process involving literature review and expert consultation to generate 26 candidate items, which were consulted upon by an international multi-stakeholder group in a two-stage Delphi survey (103 stakeholders), agreed upon in a consensus meeting (31 stakeholders) and refined through a checklist pilot (34 participants). The SPIRIT-AI extension includes 15 new items that were considered sufficiently important for clinical trial protocols of AI interventions. These new items should be routinely reported in addition to the core SPIRIT 2013 items. SPIRIT-AI recommends that investigators provide clear descriptions of the AI intervention, including instructions and skills required for use, the setting in which the AI intervention will be integrated, considerations for the handling of input and output data, the human-AI interaction and analysis of error cases. SPIRIT-AI will help promote transparency and completeness for clinical trial protocols for AI interventions. Its use will assist editors and peer reviewers, as well as the general readership, to understand, interpret and critically appraise the design and risk of bias for a planned clinical trial.
Molecular Portraits of Early Rheumatoid Arthritis Identify Clinical and Treatment Response Phenotypes.
There is a current imperative to unravel the hierarchy of molecular pathways that drive the transition of early to established disease in rheumatoid arthritis (RA). Herein, we report a comprehensive RNA sequencing analysis of the molecular pathways that drive early RA progression in the disease tissue (synovium), comparing matched peripheral blood RNA-seq in a large cohort of early treatment-naive patients, namely, the Pathobiology of Early Arthritis Cohort (PEAC). We developed a data exploration website (https://peac.hpc.qmul.ac.uk/) to dissect gene signatures across synovial and blood compartments, integrated with deep phenotypic profiling. We identified transcriptional subgroups in synovium linked to three distinct pathotypes: fibroblastic pauci-immune pathotype, macrophage-rich diffuse-myeloid pathotype, and a lympho-myeloid pathotype characterized by infiltration of lymphocytes and myeloid cells. This is suggestive of divergent pathogenic pathways or activation disease states. Pro-myeloid inflammatory synovial gene signatures correlated with clinical response to initial drug therapy, whereas plasma cell genes identified a poor prognosis subgroup with progressive structural damage.
Characterization of disease course and remission in early seropositive rheumatoid arthritis: results from the TACERA longitudinal cohort study.
BACKGROUND: To characterise disease course and remission in a longitudinal observational study of newly diagnosed, initially treatment-naïve patients with seropositive rheumatoid arthritis (RA). METHODS: Patients with early untreated seropositive RA were recruited from 28 UK centres. Multiple clinical and laboratory measures were collected every 3 months for up to 18 months. Disease activity was measured using the 28-joint Disease Activity Score with C-reactive protein (DAS28-CRP) and Simplified Disease Activity Index (SDAI). Logistic regression models examined clinical predictors of 6-month remission and latent class mixed models characterised disease course. RESULTS: We enrolled 275 patients of whom 267 met full eligibility and provided baseline data. According to SDAI definition, 24.3% attained 6-month remission. Lower baseline Health Assessment Questionnaire (HAQ) and SDAI predicted 6-month remission (p = 0.013 and 0.011). Alcohol intake and baseline prescribing of methotrexate with a second disease-modifying antirheumatic drug (DMARD; vs monotherapy without glucocorticoids) were also predictive. Three distinct SDAI trajectory subpopulations emerged; corresponding to an inadequate responder group (6.5%), and higher and lower baseline activity responder groups (22.4% and 71.1%). Baseline HAQ and Short Form-36 Health Survey - Mental Component Score (SF-36 MCS) distinguished these groups. In addition, a number of baseline clinical predictors correlated with disease activity severity within subpopulations. Beneficial effects of alcohol intake were found across subpopulations. CONCLUSION: Three distinct disease trajectory subpopulations were identified. Differential effects of functional and mental well-being, alcohol consumption, and baseline RA medication prescribing on disease activity severity were found across subpopulations. Heterogeneity across trajectories cannot be fully explained by baseline clinical predictors. We hypothesise that biological markers collected early in disease course (within 6 months) may help patient management and better targeting of existing and novel therapies.
Anti-CD5 therapy decreases severity of established disease in collagen type II-induced arthritis in DBA/1 mice.
Collagen-induced arthritis has been widely used as an animal model of rheumatoid arthritis. We have used this model with a view to determining potential therapeutic targets for the treatment of human disease. To do this we have attempted to modulate the progression of established arthritis over a 10-day time period following the first appearance of disease, by i.p. injection of one of three different MoAbs. These consist of a rat IgG2a specific for the CD5 antigen expressed on all T cells and a subpopulation of B cells, a mouse IgG2b recognizing the CD72 antigen, and a rat IgM specific for the B220 molecule, CD72 and B220 both being expressed on all B cells. None of the three MoAbs had depleting activity in vivo. The progression of arthritis was monitored both clinically, and histologically. The effects of treatment with anti-CD5 and anti-CD72 antibodies were compared with control antibodies of the same species class and subclass. In the case of anti-B220 antibodies, the effects of treatment were compared with administration of PBS. Of these MoAbs, only treatment with anti-CD5 resulted in disease amelioration with significant decrease in disease severity in 60% of the animals. These changes became apparent 6 days after initiation of treatment. There were no significant differences in serum levels of IgG antibodies to native bovine collagen type II between the groups of treated and control mice. Possible mechanisms underlying the modification of disease expression following treatment with anti-CD5 MoAb are discussed.
Human neutrophils secrete vascular endothelial growth factor.
Vascular endothelial growth factor (VEGF) is a multifunctional cytokine that plays a pivotal role in mediating neovascularization as well as other endothelial cell alterations during inflammation. In this study, we demonstrate that human neutrophils are a source of VEGF. We observed that isolated blood neutrophils released VEGF in response to different stimuli and we demonstrated by immunohistochemistry that neutrophils infiltrating inflamed tissues contain VEGF. These results indicate that neutrophil-derived VEGF may be instrumental in regulating vascular responses during acute and chronic inflammation.
Biologic therapies for rheumatoid arthritis targeting TNF-α and IL-1
'Biologics' are protein-based drugs derived from living organisms and are designed to either inhibit or augment a specific component of the immune system. Examples include antibodies directed against very specific molecular components of the immune response, for example, pro-inflammatory cytokines, or naturally occurring cytokine inhibitors such as IL-1 receptor antagonist (IL-1ra). © 2007 Springer-Verlag Berlin Heidelberg.
Autoimmunity - Rheumatoid Arthritis
This chapter discusses autoimmunity in rheumatoid arthritis (RA). The clinical presentation of RA is heterogeneous with a wide spectrum of age of onset, degree of joint involvement, and severity. Although the cause of RA remains unknown, advances in molecular technology have facilitated identification of cell subsets and cytokines contributing to the inflammatory and destructive components of the disease. The majority of biologic markers of potential value in the diagnosis and assessment of outcome in RA are measured in peripheral blood or urine. Although, in general, cytokines and immune cell subsets within the peripheral blood compartment are not measured clinically they are considered to be important in the pathogenesis of RA. In terms of RA diagnosis, rheumatoid factors remain the sole serological measure included in the widely used American College of Rheumatology classification criteria for RA. However, there is currently increasing interest in the measurement of antibodies to cyclic citrullinated peptides (anti-CCP) as a more specific marker of RA. The chapter discusses principles behind the measurement of biologic markers and the markers under investigation in the diagnosis and assessment of outcome in RA. © 2005 Elsevier Ltd. All rights reserved.
Secretion of vascular endothelial growth factor by human neutrophils
Vascular endothelial growth factor (VEGF) is produced by a variety of cells and plays a pivotal role in inflammation by mediating vascular permeability and angiogenesis. The aim of this study was to establish whether neutrophils may act as a local source of VEGF. Human neutrophils were isolated from citrated venous blood by sequential sedimentation and density centrifugation and VEGF release evaluated after exposure to ionomyrin (0.1-10μg/ml), phorbol dibutyrate (0.1-10μg/ml) or opsonised zymosan. Controls included cells treated with medium alone or dimethylsulphoxide (DMSO). VEGF was assayed by ELISA using antibodies against recombinant human VEGF (R&D Systems) and an immunoperoxidase technique. Ionomycin, phorbol dibutyrate and zymosan activated neutrophils secreted extracellular VFGF in a stimulant, time and dose dependent manner whereas less than 10% of the total available VEGF was secreted by control cells. In separate experiments, these results were confirmed by both Western blotting and immunocytochemistry. Activated neutrophils are, therefore, a potential source of VEGF in inflamed tissue which suggests that they may have a strategic role in the regulation of angiogenesis in acute and chronic inflammation.