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We are pleased to announce that today the University of Oxford MRC Brain Network Dynamics Unit joins the Nuffield Department of Clinical Neurosciences (NDCN) as a sixth division.
The profile of gastrointestinal dysfunction in prodromal to late-stage Parkinson's disease.
Gastrointestinal dysfunction (GID) may play a key role in Parkinson's disease (PD) but its relationship with disease progression remains unclear. We recruited 404 PD cases, 37 iRBD (isolated REM Sleep Behaviour Disorder) and 105 controls. Participants completed the Gastrointestinal Dysfunction Scale for PD (GIDS-PD) and standardised disease severity assessments. Whole gut transit time (WGTT) was measured by ingestion of blue dye and recorded time to blue stools appearance ('Blue Poop Challenge') in a subset of PD cases. Gastrointestinal symptoms were more common and prevalent in iRBD and PD versus controls, and WGTT was significantly higher in PD versus controls. After adjustment for confounding factors, disease stage was not a significant predictor of GIDS-PD Constipation or Bowel Irritability scores. Longitudinal assessment of GIDS-PD scores and WGTT confirmed stability over a 4 year period. Bowel dysfunction may be a phenotypic feature in a subset of Parkinson's with implications for patient stratification and management.
Advancing atmospheric solids analysis probe mass spectrometry applications: a multifaceted approach to optimising clinical data set generation.
The use of rapid mass spectrometry techniques, such as atmospheric-solids-analysis-probe mass spectrometry (ASAP-MS), in the analysis of metabolite patterns in clinical samples holds significant promise for developing new diagnostic tools and enabling rapid disease screening. The rapid measurement times, ease of use, and relatively low cost of ASAP-MS makes it an appealing option for use in clinical settings. However, despite the potential of such approaches, a number of important experimental considerations are often overlooked. As well as instrument-specific choices and settings, these include the treatment of background noise and/or contaminant peaks in the mass spectra, and the influence of consumables, different users, and batch effects more generally. The present study assesses the impact of these various factors on measurement accuracy and reproducibility, using human brain and cerebrospinal fluid samples as examples. Based on our results, we make a series of recommendations relating to optimisation of measurement and cleaning protocols, consumable selection, and batch effect detection and correction, in order to optimise the reliability and reproducibility of ASAP-MS measurements in clinical settings.
ZFP36-family RNA-binding proteins in regulatory T cells reinforce immune homeostasis
RNA binding proteins (RBP) of the ZFP36 family limit the differentiation and effector functions of CD4 and CD8 T cells, but little is known of their expression or function in regulatory T (Treg) cells. By using Treg cell-restricted deletion of Zfp36 family members we identify the role of Zfp36l1 and Zfp36l2 in Treg cells to maintain immune homeostasis. Mice with Treg cells deficient in these RBP display an inflammatory phenotype with an expansion in the numbers of type-2 conventional dendritic cells, T effector cells, T follicular helper and germinal center B cells and elevated serum cytokines and immunoglobulins. In the absence of Zfp36l1 and Zfp36l2, the pool of cycling CTLA-4 in naïve Treg cells is reduced, Treg cells are less sensitive to IL-2 and IL-7 but are more sensitive to IFNγ. In mice lacking both RBP in Treg cells, the deletion of a single allele of Ifng is sufficient to ameliorate the pathology. Our results indicate that ZFP36L1 and ZFP36L2 regulate the availability of IFNγ and are required for the maintenance of Treg cell stability. Thus, ZFP36L1 and ZFP36L2 regulate multiple pathways that enable Treg cells to enforce immune homeostasis.
Case report on severe myelin oligodendrocyte glycoprotein antibody-associated disease relapse after ectopic pregnancy and laparoscopic medical abortion: relevance of peripheral inflammation for demyelinating disease activity.
BACKGROUND: Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a rare neurological condition. Tubal ectopic pregnancy is an important cause of maternal morbidity and mortality worldwide. Regular pregnancy has a disease-modifying effect on MOGAD, with an increased relapse rate postpartum. Still, there are neither case reports nor cohort studies on abortions and ectopic pregnancy as a disease-modifying event for MOGAD. MATERIALS AND METHODS: This is a case report on a severe MOGAD relapse after ectopic pregnancy and laparoscopic abortion. DISCUSSION: For the first time we described that elevated interleukin-1 (IL-1), which was found in cerebrospinal fluid in the current case may be pathogenetically related to ectopic pregnancy. Rituximab (anti-CD20 treatment), downregulated IL-1 and TNF-alfa inflammatory pathways thus is an appropriate drug of choice to treat relapse. Cytokines secreted during ectopic pregnancy could play a disease-modifying role in multiple sclerosis and Guillian-Barré syndrome. CONCLUSION: The first case report of a MOGAD severe relapse after ectopic pregnancy and laparoscopic abortion which resolved with rituximab treatment.
Dreaming of Better Treatments: Advances in Drug Development for Sleep Medicine and Chronotherapy.
Throughout history, the development of new sleep medicines has been driven by progress in our understanding of the mechanisms underlying sleep. Ancient civilisations used their understanding of the sedative nature of natural herbs and compounds to induce sleep. The discovery of barbiturates and bromides heralded a new era of synthetic sleep medicine in the 19th century. This was followed by the development of benzodiazepines that were used to inhibit signalling throughout the brain by promoting gamma-amino butyric acid release and thereby produce loss of consciousness. As our understanding of sleep has deepened, newer therapies have more specifically targeted the wake-inducing neurotransmitter orexin with fewer side effects. Given the newly highlighted role of kinases in sleep/wake regulation, we predict that the next breakthroughs in sleep medicine will likely target these kinases. Given the fundamental role that sleep plays in maintaining brain health through processes such as glymphatic clearance, sleep medicine has therapeutic potential beyond just sleep. Recent evidence suggests that sleep disruptions directly contribute to the build-up of pathological neuronal proteins in neurodegenerative disorders. Therefore, sleep medicine could improve prognosis in disorders such as these. Great attention must be paid to the mechanism of action of each sleep medicine, however, as sleep medicines which do not fully mimic sleep could actually worsen disease progression.
Positivity Rate of PD-L1 Expression and Its Clinical Significance in Vulvar Cancer: A Systematic Review and Meta-Analysis
The prevalence and prognostic value of programmed death ligand 1 (PD-L1) expression, as a potential biomarker in vulvar squamous cell carcinomas (VSCCs), remain underexplored. We searched the PubMed, Scopus, Embase, and Cochrane Library databases until July 2024 for articles examining PD-L1 expression in VSCCs. Random-effects meta-analyses summarized PD-L1 expression overall and in subgroups by immunohistochemistry antibody type, positivity cutoff, tumor stage, and HPV positivity. Additionally, random-effects meta-analyses summarized the association between PD-L1 positivity and cancer prognosis. We included 26 studies comprising 1912 VSCC cases. The summary PD-L1 positivity rate in tumor cells was 59.9% (95% confidence interval [CI]: 47.7–71.4%; I2 = 96%, n = 26), influenced by the different cutoff thresholds utilized to define PD-L1 positivity. Compared to tumor cells, positivity rates were higher in intratumoral immune cells (75.6%; 95%CI: 52.9–92.5; I2 = 95.4%, n = 6) and peritumoral cells (78.9%; 95%CI: 54.4–95.5%; I2 = 91%, n = 3) but with overlapping 95%CIs. No heterogeneity was observed in the rates by tumor stage or HPV status. Positive PD-L1 expression was associated with worse overall (hazard ratio [HR] = 1.43; 95%CI: 1.06–1.93; I2 = 28.9%, n = 7) and progression-free survival (HR = 1.57; 95%CI: 1.07–2.3; I2 = 38.3%, n = 5). The PD-L1 expression rate in VSCC tumor cells varied across studies, was influenced by differences in immunohistochemical evaluation, and was identified as an unfavorable prognostic factor. Large, prospective, multicenter studies with standardized protocols are crucial to further elucidate the clinical significance of PD-L1 expression in VSCCs.
Thalamic deep brain stimulation for central poststroke pain syndrome: an international multicenter study.
OBJECTIVE: The effectiveness and optimal stimulation site of deep brain stimulation (DBS) for central poststroke pain (CPSP) remain elusive. The objective of this retrospective international multicenter study was to assess clinical as well as neuroimaging-based predictors of long-term outcomes after DBS for CPSP. METHODS: The authors analyzed patient-based clinical and neuroimaging data of previously published and unpublished cohorts from 6 international DBS centers. DBS leads were reconstructed and normalized. A stimulation map was constructed on the basis of individual stimulation settings and associated outcomes. Furthermore, the authors projected the individual segmented stroke lesions and volumes of tissue activated (VTAs) of the stimulating electrode onto a normalized human connectome to obtain the connectivity profiles of the individual lesions and VTAs. RESULTS: The authors analyzed the data of 54 patients, of whom 15 were excluded from the final analysis due to a lack of imaging data. Among the remaining 39 patients from 6 different cohorts, the authors found 14 (35.9%) responders who were defined by pain relief of at least 50% at 12-month follow-up. Stimulation mapping identified areas in the posterior limb of the internal capsule, the sensorimotor thalamus, and the medial and intralaminar thalamus as effective for pain reduction. Baseline characteristics did not differ between responders and nonresponders. The stimulation sites of the responders showed significantly reduced structural connectivity to the sensory areas of the cerebral cortex compared to nonresponders. CONCLUSIONS: This comprehensive, multicenter analysis corroborates the efficacy of DBS in treating CPSP for a relevant number of patients. The posterior limb of the internal capsule and the sensorimotor thalamus emerged as potential stimulation sweet spots. The difference in structural connectivity between responders and nonresponders may constitute a biomarker of effective stimulation that can help guide surgical planning in future well-designed prospective trials.
Prevalence of weakness and factors mediating discrepancy between reported and observed leg weakness in people with sciatica
Abstract Purpose To establish the prevalence and agreement between reported and observed leg weakness in people with sciatica. To establish which factors mediate any identified difference between reported and observed leg weakness in people with sciatica. Methods 68 people with a clinical diagnosis of sciatica, records from spinal service, secondary care NHS Hospital, England, UK reviewed. Primary outcome measures were the sciatica bothersome index for reported leg weakness and the Medical Research Council scale for observed weakness. Agreement was established with Cohen’s Kappa and intraclass correlation coefficient. Potential factors that may mediate a difference between reported and observed weakness included leg pain, sciatica bothersome index sensory subscale, age, hospital anxiety and depression subscale for anxiety. Results 85% of patients reported weakness but only 34% had observed weakness. Cohen’s Kappa (0.066, 95% CI − 0.53, 0.186; p = 0.317)] and ICC 0.213 (95% CI − 0.26, 0.428, p = 0.040) both showed poor agreement between reported and observed weakness. The difference between reported and observed measures of weakness was mediated by the severity of leg pain (b = 0.281, p = 0.024) and age (b = 0.253, p = 0.042). Conclusion There is a high prevalence of reported leg weakness in people with sciatica, which is not reflected in observed clinical measures of weakness. Differences between reported and observed weakness may be driven by the severity of leg pain and age. Further work needs to establish whether other objective measures can detect patient reported weakness.
Analysis of infection rates in neuromyelitis optica spectrum disorder: Comparing satralizumab treatment in SAkuraMoon, post-marketing, and US-based health claims data.
Satralizumab showed a comparable safety profile versus placebo in 2 pivotal neuromyelitis optica spectrum disorder (NMOSD) studies. We analyzed infection rates with long-term satralizumab treatment in the open-label study, SAkuraMoon, and in a post-marketing setting (PMS), comparing frequencies with US-based health claims real-world data (US-RWD). Incidence rates of infection per 100 patient-years (IR/100 PY) were analyzed in the SAkura studies (clinical cut-off date: 31 January 2023). Reported rates of infection ( %) in a PMS using Periodic Benefit-Risk Evaluation Reports (2020-2023), and cumulative incidence of infections ( %) from the US PharMetrics claims data in NMOSD patients (2017-2022) were analyzed. 166 patients (SAkura studies), 2951 patients (PMS) and 2872 patients (US-RWD) were included. In the SAkura studies, the incidence rates of infection, serious infection, and sepsis were lower versus the double-blind period (IR/100 PY [95 % confidence intervals (Tur, C. et al.)] infection 91.7 [85.5-98.3] vs 113.0 [98.6-129.0]; serious infection 2.6 [1.7-3.9] vs 4.1 [1.8-8.1]; sepsis 0.6 [0.2-1.3] vs 1.0 [0.1-3.7], respectively). In a PMS, reported rates of infection, serious infection, and sepsis were 7.3 %, 3.8 %, and 0.6 %, respectively. In the US-RWD, cumulative incidence of infection, serious infection, and sepsis in NMOSD were 67.3 %, 8.4 %, and 4.9 %, respectively. Concomitant IST use, comorbidities, Expanded Disability Status Scale score ≥4.0, and age >65 years were potential confounders of sepsis. US-RWD indicated infection is a major comorbidity in NMOSD, independent of satralizumab treatment. Infection rates were consistently lower in satralizumab-treated patients compared with US-RWD. Trial Registration: NCT04660539(SAkuraMoon), NCT02028884(SAkuraSky), NCT02073279(SAkuraStar).
Automated quality control of T1-weighted brain MRI scans for clinical research datasets: methods comparison and design of a quality prediction classifier
Abstract T1-weighted (T1w) MRI is widely used in clinical neuroimaging for studying brain structure and its changes, including those related to neurodegenerative diseases, and as anatomical reference for analysing other modalities. Ensuring high-quality T1w scans is vital as image quality affects reliability of outcome measures. However, visual inspection can be subjective and time-consuming, especially with large datasets. The effectiveness of automated quality control (QC) tools for clinical cohorts remains uncertain. In this study, we used T1w scans from elderly participants within ageing and clinical populations to test the accuracy of existing QC tools with respect to visual QC and to establish a new quality prediction framework for clinical research use. Four datasets acquired from multiple scanners and sites were used (N = 2438, 11 sites, 39 scanner manufacturer models, 3 field strengths – 1.5T, 3T, 2.9T, patients and controls, average age 71 ± 8 years). All structural T1w scans were processed with two standard automated QC pipelines (MRIQC and CAT12). The agreement of the accept-reject ratings was compared between the automated pipelines and with visual QC. We then designed a quality prediction framework that combines the QC measures from the existing automated tools and is trained on clinical research datasets. We tested the classifier performance using cross-validation on data from all sites together, also examining the performance across diagnostic groups. We then tested the generalisability of our approach when leaving one site out and explored how well our approach generalises to data from a different scanner manufacturer and/or field strength from those used for training, as well as on an unseen new dataset of healthy young participants with movement related artefacts. Our results show significant agreement between automated QC tools and visual QC (Kappa=0.30 with MRIQC predictions; Kappa=0.28 with CAT12’s rating) when considering the entire dataset, but the agreement was highly variable across datasets. Our proposed robust undersampling boost (RUS) classifier achieved 87.7% balanced accuracy on the test data combined from different sites (with 86.6% and 88.3% balanced accuracy on scans from patients and controls respectively). This classifier was also found to be generalisable on different combinations of training and test datasets (average balanced accuracy of leave-one-site-out = 78.2%; exploratory models on field strengths and manufacturers = 77.7%; movement related artefact dataset when including 1% scans in the training = 88.5%). While existing QC tools may not be robustly applicable to datasets comprised of older adults, they produce quality metrics that can be leveraged to train a more robust quality control classifiers for ageing and clinical cohorts.