Parent-young person lived experience of sensory dysregulation in children with tic disorders: a qualitative study.

PURPOSE: To understand the breadth of sensory dysregulation on participation in daily tasks for young people with tic disorders, as research identified that sensory dysregulation experiences are broader than the symptoms being assessed. METHODS: Eighteen semi-structured interviews were conducted with 16 families with children (5-16 years) with tic disorders. Interviews ranged from 45 to 120 min and were transcribed verbatim. Data collected from parents and young people were analysed and coded together. Thematic analysis using inductive and open coding methods was implemented using NVivo. RESULTS: The impact of sensory dysregulation on daily life may be understood through the higher-order theme: ''sensory, emotions and tics; it's a ticking time bomb'', and three subthemes: (1) we sacrifice and adapt to get daily activities done in the home, (2) my child's experience of the community environment hinders participation, and (3) sensory preferences impact our entire family. CONCLUSION: Sensory dysregulation experiences impact the entire family's quality of life, yet patient-reported sensory measures do not adequately capture the impact on the family unit and breath of symptoms. A sensory-based measure for children with tics is needed to comprehensively assess sensory dysregulation sensitivities for this population, ensuring patients' needs and effectiveness of therapy can be measured.

This qualitative study provides health professionals with a greater understanding of the sensory dysregulation experiences of children and young people with tic disorders.This study highlights that the sensory dysregulation experiences of children and young people are broader than the symptoms assessed through standardised questionnaires.To comprehensively assess and treat sensory dysregulation in clients with tics, the impact on the family unit needs to be evaluated and understood.When comprehensively assessing sensory dysregulation, understanding the interplay of tics, sensory and emotional dysregulation aids in treatment planning.

A Modular Approach for Accessing 3D Heterocycles via 1,2-Dicyanation of Planar N-Heteroarenes.

The rapid construction of three-dimensional (3D) heterocyclic frameworks is a key challenge in contemporary medicinal chemistry. The molecules with three-dimensional complexity hold a greater probability to improve clinical outcomes, solubility, selectivity for target proteins, and metabolic stability. However, the prevalence of flat molecules persists among new drug candidates, primarily owing to the multitude of chemical methods available for their synthesis. In principle, the dearomative functionalization of N-heteroarene allows for the conversion of readily available planar molecules into partially or fully saturated nitrogen heterocycles, which are most significant structural motifs of pharmaceuticals and natural products. Unfortunately, these reactions are very rare because of the inherent challenge imposed by heteroarenes' poor reactivity, rendering the process thermodynamically unfavorable. Herein, we report a modular approach for accessing 3D chemical space in translating planar heteroarenes into valuable 3D heterocycles via the installation of a highly versatile cyano group as a new vector. This approach is enabled by the in situ generation of reactive, non-symmetric iodane by combining cyanide anion and bench-stable PhI(OAc)2. This reaction represents a rare example of 1,2-dicyanation of N-heteroarenes that meets the numerous requirements for broad implementation in drug and agrochemical discovery.

High fat diet consumption and social instability stress impair stress adaptation and maternal care in C57Bl/6 dams.

Poor maternal diet and psychosocial stress represent two environmental factors that can significantly impact maternal health during pregnancy. While various mouse models have been developed to study the relationship between maternal and offspring health and behaviour, few incorporate multiple sources of stress that mirror the complexity of human experiences. Maternal high-fat diet (HF) models in rodents are well-established, whereas use of psychosocial stress interventions in female mice are still emerging. The social instability stress (SIS) paradigm, serves as a chronic and unpredictable form of social stress. To evaluate the combined effects of a poor maternal diet and intermittent social stress on maternal health and behaviour, we developed a novel maternal stress model using adult female C57Bl/6 mice. We observed that all HF+ mice demonstrated rapid weight gain, elevated fasting blood glucose levels and impaired glucose tolerance independent of the presence (+) or absence (-) of SIS. Behavioural testing output revealed anxiety-like behaviours remained similar across all groups prior to pregnancy. However, integrated anxiety z-scores revealed a mixed anxious profile amongst HF+/SIS+ females prior to pregnancy. HF+/SIS+ females also did not show reduced plasma ACTH and corticosterone levels that were observed in our other HF+ and HF- stress groups after SIS exposure. Further, HF+/SIS+ females demonstrated significant postpartum maternal neglect, resulting in fewer numbers of live offspring. These findings suggest that prolonged maternal HF diet consumption, coupled with previous exposure to SIS, places a significant burden on the maternal stress response system, resulting in reduced parental investment and negative postpartum behaviour towards offspring.

Application of the international criteria for optic neuritis in the Acute Optic Neuritis Network.

OBJECTIVE: The first international consensus criteria for optic neuritis (ICON) were published in 2022. We applied these criteria to a prospective, global observational study of acute optic neuritis (ON). METHODS: We included 160 patients with a first-ever acute ON suggestive of a demyelinating CNS disease from the Acute Optic Neuritis Network (ACON). We applied the 2022 ICON to all participants and subsequently adjusted the ICON by replacing a missing relative afferent pupillary defect (RAPD) or dyschromatopsia if magnetic resonance imaging pathology of the optical nerve plus optical coherence tomography abnormalities or certain biomarkers are present. RESULTS: According to the 2022 ICON, 80 (50%) patients were classified as definite ON, 12 (7%) patients were classified as possible ON, and 68 (43%) as not ON (NON). The main reasons for classification as NON were absent RAPD (52 patients, 76%) or dyschromatopsia (49 patients, 72%). Distribution of underlying ON etiologies was as follows: 78 (49%) patients had a single isolated ON, 41 (26%) patients were diagnosed with multiple sclerosis, 25 (16%) patients with myelin oligodendrocyte glycoprotein antibody-associated disease, and 15 (9%) with neuromyelitis optica spectrum disorder. The application of the adjusted ON criteria yielded a higher proportion of patients classified as ON (126 patients, 79%). INTERPRETATION: According to the 2022 ICON, almost half of the included patients in ACON did not fulfill the requirements for classification of definite or possible ON, particularly due to missing RAPD and dyschromatopsia. Thorough RAPD examination and formal color vision testing are critical to the application of the 2022 ICON.

Treatments and clinical outcomes in stage II colon cancer patients with 12-gene Oncotype DX Colon Recurrence Score® assay-guided therapy: real-world data.

BACKGROUND: The 12-gene Oncotype DX Colon Recurrence Score® result quantifies the recurrence risk in stage II/III colon cancer (CC). This real-world study investigated stage II CC patients whose treatment decisions incorporated the Recurrence Score® (RS) result. MATERIALS AND METHODS: This retrospective analysis of a prospectively designed cohort included all stage II, mismatch repair-proficient CC patients who underwent 12-gene testing through Clalit between January 2011 and December 2016 and had available data with a minimum 3-year follow-up. RESULTS: The analysis included 938 patients {median age 68 [interquartile range (IQR) 60-76] years; 96% T3 tumors}. The median RS was 26 (IQR 19-33) and the three RS categories (0-29, 30-40, 41-100) included 65%, 24%, and 11% of patients, respectively. Chemotherapy (CT) use differed significantly between the three RS categories (14%, 36%, and 60%, respectively; P < 0.001). The CT and observation-only groups were imbalanced with worse clinicopathologic characteristics in the former. Among observation-only patients, Kaplan-Meier (KM) estimates for recurrence-free interval (RFI) and CC-specific survival (CCSS) differed significantly between the three RS categories (P < 0.001). Clinical outcomes by treatment (CT versus observation) within each RS category revealed no differences in RFI and CCSS in the RS 0-29 and 30-40 categories. In contrast, in the RS 41-100 category, the difference in RFI trended toward significance (P = 0.066), and for CCSS, a statistically significant difference was observed, with better outcomes among CT-treated patients (P = 0.035). CONCLUSIONS: RS results are prognostic in stage II CC. Among RS 41-100 patients, outcomes were better in CT-treated versus observation-only patients despite worse clinicopathologic characteristics, suggesting that CT confers clinical benefit in high-risk patients.

International consensus definitions for infection-triggered encephalopathy syndromes.

AIM: To develop standardized diagnostic criteria for 'infection-triggered encephalopathy syndrome (ITES)' and five specific clinical syndromes of ITES. METHOD: The draft definitions were based on existing criteria, standardized, and discussed by a panel of international experts using nominal group technique over 18 months to achieve consensus. All criteria use the same format: (1) presence of infection/fever; (2) clinical features including encephalopathy; (3) neuroradiological features on magnetic resonance imaging; (4) exclusion of other causes. RESULTS: We first highlighted differences between ITES and infectious and autoimmune encephalitis, which is the most important differential diagnosis. Consensus was achieved to define five specific ITESs: acute encephalopathy with biphasic seizures and late reduced diffusion; acute necrotizing encephalopathy; mild encephalopathy with a reversible splenial lesion; acute fulminant cerebral oedema; and acute shock with encephalopathy and multiorgan failure. Two further conditions that are currently classified as epilepsy syndromes but have similar features to ITES, namely febrile infection-related epilepsy syndrome and hemiconvulsion-hemiplegia-epilepsy syndrome, are also discussed. INTERPRETATION: The consensus definition is expected to improve awareness of this disease concept, provide diagnostic framework, and facilitate future international research and clinical trials.

Hereditary C1q Deficiency is Associated with Type 1 Interferon-Pathway Activation and a High Risk of Central Nervous System Inflammation.

Hereditary C1q deficiency (C1QDef) is a rare monogenic disorder leading to defective complement pathway activation and systemic lupus erythematosus (SLE)-like manifestations. The link between impairment of the complement cascade and autoimmunity remains incompletely understood. Here, we assessed type 1 interferon pathway activation in patients with C1QDef. Twelve patients with genetically confirmed C1QDef were recruited through an international collaboration. Clinical, biological and radiological data were collected retrospectively. The expression of a standardized panel of interferon stimulated genes (ISGs) in peripheral blood was measured, and the level of interferon alpha (IFNα) protein in cerebrospinal fluid (CSF) determined using SIMOA technology. Central nervous system (encompassing basal ganglia calcification, encephalitis, vasculitis, chronic pachymeningitis), mucocutaneous and renal involvement were present, respectively, in 10, 11 and 2 of 12 patients, and severe infections recorded in 2/12 patients. Elevated ISG expression was observed in all patients tested (n = 10/10), and serum and CSF IFNα elevated in 2/2 patients. Three patients were treated with Janus-kinase inhibitors (JAKi), with variable outcome; one displaying an apparently favourable response in respect of cutaneous and neurological features, and two others experiencing persistent disease despite JAKi therapy. To our knowledge, we report the largest original series of genetically confirmed C1QDef yet described. Additionally, we present a review of all previously described genetically confirmed cases of C1QDef. Overall, individuals with C1QDef demonstrate many characteristics of recognized monogenic interferonopathies: particularly, cutaneous involvement (malar rash, acral vasculitic/papular rash, chilblains), SLE-like disease, basal ganglia calcification, increased expression of ISGs in peripheral blood, and elevated levels of CSF IFNα.

Challenges with sirolimus experimental data to inform QSP model of post-transplantation cyclophosphamide regimens.

Dose optimization of sirolimus may further improve outcomes in allogeneic hematopoietic cell transplant (HCT) patients receiving post-transplantation cyclophosphamide (PTCy) to prevent graft-versus-host disease (GVHD). Sirolimus exposure-response association studies in HCT patients (i.e., the association of trough concentration with clinical outcomes) have been conflicting. Sirolimus has important effects on T-cells, including conventional (Tcons) and regulatory T-cells (Tregs), both of which have been implicated in the mechanisms by which PTCy prevents GVHD, but there is an absence of validated biomarkers of sirolimus effects on these cell subsets. Considering the paucity of existing biomarkers and the complexities of the immune system, we conducted a literature review to inform a quantitative systems pharmacology (QSP) model of GVHD. The published literature presented multiple challenges. The sirolimus pharmacokinetic models insufficiently describe sirolimus distribution to relevant physiological compartments. Despite multiple publications describing sirolimus effects on Tcons and Tregs in preclinical and human ex vivo models, consistent parameters relating sirolimus concentrations to circulating Tcons and Tregs could not be found. Each aspect presents a challenge in building a QSP model of sirolimus and its temporal effects on T-cell subsets and GVHD prevention. To optimize GVHD prevention regimens, phase I studies and systematic studies of immunosuppressant concentration-effect association are needed for QSP modeling.

Low neighborhood socioeconomic status is associated with poor outcomes in young adults with colorectal cancer.

BACKGROUND: The incidence of early-onset colorectal cancer has increased markedly over the past decade. Although established for older adults, there are limited data on socioeconomic and racial disparities in screening, treatment, and outcomes in this distinct group. METHODS: Adults with primary colorectal cancer diagnosed at age <50 were identified from the Surveillance, Epidemiology, and End Results database. The exposure of interest was neighborhood socioeconomic status based on the Yost Index, a census-tract level composite score of neighborhood economic health. Univariate analysis was performed with χ2 analyses. Logistic regression models were created to evaluate the association of neighborhood socioeconomic status (Yost Index quintile) with metastasis at presentation and surgical intervention. Kaplan-Meier and Cox proportional hazards models were created. RESULTS: In total, 45,660 early-onset colorectal cancer patients were identified; 16.8% (7,679) were in the lowest quintile of neighborhood socioeconomic status. Patients with the lowest neighborhood socioeconomic status were 1.13 times (95% confidence interval 1.06-1.21) more likely to present with metastases and had lower survival (hazard ratio 1.45, 95% confidence interval 1.37-1.53) compared to those with the highest neighborhood socioeconomic status. Non-Hispanic Black patients were more likely to present with metastatic disease (odds ratio 1.11, 95% confidence interval 1.05-1.19), less likely to undergo surgery for localized or regional disease (odds ratio 0.48, 95% confidence interval 0.43-0.53), and had lower survival (hazard ratio 1.21, 95% confidence interval 1.15-1.27) than non-Hispanic White patients. CONCLUSION: Socioeconomic and racial disparities in early-onset colorectal cancer span diagnosis, treatment, and survival. As the disease burden of early-age onset colorectal cancer increases, interventions to boost early diagnosis and access to surgery are necessary to improve survival among minorities and patients with low neighborhood socioeconomic status.

Beyond Strain Release: Delocalization-Enabled Organic Reactivity.

The release of strain energy is a fundamental driving force for organic reactions. However, absolute strain energy alone is an insufficient predictor of reactivity, evidenced by the similar ring strain but disparate reactivity of cyclopropanes and cyclobutanes. In this work, we demonstrate that electronic delocalization is a key factor that operates alongside strain release to boost, or even dominate, reactivity. This delocalization principle extends across a wide range of molecules containing three-membered rings such as epoxides, aziridines, and propellanes and also applies to strain-driven cycloaddition reactions. Our findings lead to a "rule of thumb" for the accurate prediction of activation barriers in such systems, which can be easily applied to reactions involving many of the strained building blocks commonly encountered in organic synthesis, medicinal chemistry, polymer science, and bioconjugation. Given the significance of electronic delocalization in organic chemistry, for example in aromatic π-systems and hyperconjugation, we anticipate that this concept will serve as a versatile tool to understand and predict organic reactivity.

The clinical relevance of MOG antibody testing in cerebrospinal fluid.

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is diagnosed by serum MOG-immunoglobulin G (MOG-IgG) in association with typical demyelination. 111/1127 patients with paired CSF/serum samples were seropositive for MOG-IgG. Only 7/1016 (0.7%) seronegative patients had CSF-restricted MOG-IgG. While 3/7 patients had longitudinally extensive transverse myelitis, four had a confirmed alternate diagnosis (three multiple sclerosis, one CNS vasculitis). In a national referral setting, CSF-restricted MOG-IgG had a low sensitivity (2.63%, 95%CI 0.55-7.50%) and low positive predictive value (1.97%, 95%CI 0.45-8.13%). We strongly recommend serum as the preferred diagnostic biospecimen, and urge caution in the interpretation of CSF-restricted MOG-IgG in patients without clinico-radiological features consistent with MOGAD.

HLA and KIR genetic association and NK cells in anti-NMDAR encephalitis.

Introduction: Genetic predisposition to autoimmune encephalitis with antibodies against N-methyl-D-aspartate receptor (NMDAR) is poorly understood. Given the diversity of associated environmental factors (tumors, infections), we hypothesized that human leukocyte antigen (HLA) and killer-cell immunoglobulin-like receptors (KIR), two extremely polymorphic gene complexes key to the immune system, might be relevant for the genetic predisposition to anti-NMDAR encephalitis. Notably, KIR are chiefly expressed by Natural Killer (NK) cells, recognize distinct HLA class I allotypes and play a major role in anti-tumor and anti-infection responses. Methods: We conducted a Genome Wide Association Study (GWAS) with subsequent control-matching using Principal Component Analysis (PCA) and HLA imputation, in a multi-ethnic cohort of anti-NMDAR encephalitis (n=479); KIR and HLA were further sequenced in a large subsample (n=323). PCA-controlled logistic regression was then conducted for carrier frequencies (HLA and KIR) and copy number variation (KIR). HLA-KIR interaction associations were also modeled. Additionally, single cell sequencing was conducted in peripheral blood mononuclear cells from 16 cases and 16 controls, NK cells were sorted and phenotyped. Results: Anti-NMDAR encephalitis showed a weak HLA association with DRB1*01:01~DQA1*01:01~DQB1*05:01 (OR=1.57, 1.51, 1.45; respectively), and DRB1*11:01 (OR=1.60); these effects were stronger in European descendants and in patients without an underlying ovarian teratoma. More interestingly, we found increased copy number variation of KIR2DL5B (OR=1.72), principally due to an overrepresentation of KIR2DL5B*00201. Further, we identified two allele associations in framework genes, KIR2DL4*00103 (25.4% vs. 12.5% in controls, OR=1.98) and KIR3DL3*00302 (5.3% vs. 1.3%, OR=4.44). Notably, the ligands of these KIR2DL4 and KIR3DL3, respectively, HLA-G and HHLA2, are known to act as immune checkpoint with immunosuppressive functions. However, we did not find differences in specific KIR-HLA ligand interactions or HLA-G polymorphisms between cases and controls. Similarly, gene expression of CD56dim or CD56bright NK cells did not differ between cases and controls. Discussion: Our observations for the first time suggest that the HLA-KIR axis might be involved in anti-NMDAR encephalitis. While the genetic risk conferred by the identified polymorphisms appears small, a role of this axis in the pathophysiology of this disease appears highly plausible and should be analyzed in future studies.

Mathematical Modeling Unveils Optimization Strategies for Targeted Radionuclide Therapy of Blood Cancers.

Targeted radionuclide therapy is based on injections of cancer-specific molecules conjugated with radioactive nuclides. Despite the specificity of this treatment, it is not devoid of side-effects limiting its use and is especially harmful for rapidly proliferating organs well perfused by blood, like bone marrow. Optimization of radioconjugates administration accounting for toxicity constraints can increase treatment efficacy. Based on our experiments on disseminated multiple myeloma mouse model treated by 225Ac-DOTA-daratumumab, we developed a mathematical model which investigation highlighted the following principles for optimization of targeted radionuclide therapy. 1) Nuclide to antibody ratio importance. The density of radioconjugates on cancer cells determines the density of radiation energy deposited in them. Low labeling ratio as well as accumulation of unlabeled antibodies and antibodies attached to decay products in the bloodstream can mitigate cancer radiation damage due to excessive occupation of specific receptors by antibodies devoid of radioactive nuclides. 2) Cancer binding capacity-based dosing. The rate of binding of drug to cancer cells depends on the total number of their specific receptors, which therefore can be estimated from the pharmacokinetic curve of diagnostic radioconjugates. Injection of doses significantly exceeding cancer binding capacity should be avoided since radioconjugates remaining in the bloodstream have negligible efficacy to toxicity ratio. 3) Particle range-guided multi-dosing. The use of short-range particle emitters and high-affinity antibodies allows for robust treatment optimization via initial saturation of cancer binding capacity, enabling redistribution of further injected radioconjugates and deposited dose towards still viable cells that continue expressing specific receptors.

'High hopes for treatment': Australian stakeholder perspectives of the clinical translation of advanced neurotherapeutics for rare neurological diseases.

INTRODUCTION: Advanced therapies offer unprecedented opportunities for treating rare neurological disorders (RNDs) in children. However, health literacy, perceptions and understanding of novel therapies need elucidation across the RND community. This study explored healthcare professionals' and carers' perspectives of advanced therapies in childhood-onset RNDs. METHODS: In this mixed-methodology cross-sectional study, 20 healthcare professionals (clinicians, genetic counsellors and scientists) and 20 carers completed qualitative semistructured interviews and custom-designed surveys. Carers undertook validated psychosocial questionnaires. Thematic and quantitative data analysis followed. RESULTS: Participants described high positive interest in advanced therapies, but low knowledge of, and access to, reliable information. The substantial 'therapeutic gap' and 'therapeutic odyssey' common to RNDs were recognised in five key themes: (i) unmet need and urgency for access; (ii) seeking information; (iii) access, equity and sustainability; (iv) a multidisciplinary and integrated approach to care and support and (v) difficult decision-making. Participants were motivated to intensify RND clinical trial activity and access to advanced therapies; however, concerns around informed consent, first-in-human trials and clinical trial procedures were evident. There was high-risk tolerance despite substantial uncertainties and knowledge gaps. RNDs with high mortality, increased functional burdens and no alternative therapies were consistently prioritised for the development of advanced therapies. However, little consensus existed on prioritisation to treatment access. CONCLUSIONS: This study highlights the need to increase clinician and health system readiness for the clinical translation of advanced therapeutics for RNDs. Co-development and use of educational and psychosocial resources to support clinical decision-making, set therapeutic expectations and promotion of equitable, effective and safe delivery of advanced therapies are essential. PATIENT OR PUBLIC CONTRIBUTION: Participant insights into the psychosocial burden and information need to enhance the delivery of care in this formative study are informing ongoing partnerships with families, including co-production and dissemination of psychoeducational resources featuring their voices hosted on the Sydney Children's Hospitals Network website SCHN Brain-Aid Resources.

Designing combination therapies for cancer treatment: application of a mathematical framework combining CAR T-cell immunotherapy and targeted radionuclide therapy.

Introduction: Cancer combination treatments involving immunotherapies with targeted radiation therapy are at the forefront of treating cancers. However, dosing and scheduling of these therapies pose a challenge. Mathematical models provide a unique way of optimizing these therapies. Methods: Using a preclinical model of multiple myeloma as an example, we demonstrate the capability of a mathematical model to combine these therapies to achieve maximum response, defined as delay in tumor growth. Data from mice studies with targeted radionuclide therapy (TRT) and chimeric antigen receptor (CAR)-T cell monotherapies and combinations with different intervals between them was used to calibrate mathematical model parameters. The dependence of progression-free survival (PFS), overall survival (OS), and the time to minimum tumor burden on dosing and scheduling was evaluated. Different dosing and scheduling schemes were evaluated to maximize the PFS and optimize timings of TRT and CAR-T cell therapies. Results: Therapy intervals that were too close or too far apart are shown to be detrimental to the therapeutic efficacy, as TRT too close to CAR-T cell therapy results in radiation related CAR-T cell killing while the therapies being too far apart result in tumor regrowth, negatively impacting tumor control and survival. We show that splitting a dose of TRT or CAR-T cells when administered in combination is advantageous only if the first therapy delivered can produce a significant benefit as a monotherapy. Discussion: Mathematical models are crucial tools for optimizing the delivery of cancer combination therapy regimens with application along the lines of achieving cure, maximizing survival or minimizing toxicity.

MOG antibody-associated optic neuritis.

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is a demyelinating disorder, distinct from multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD). MOGAD most frequently presents with optic neuritis (MOG-ON), often with characteristic clinical and radiological features. Bilateral involvement, disc swelling clinically and radiologically, and longitudinally extensive optic nerve hyperintensity with associated optic perineuritis on MRI are key characteristics that can help distinguish MOG-ON from optic neuritis due to other aetiologies. The detection of serum MOG immunoglobulin G utilising a live cell-based assay in a patient with a compatible clinical phenotype is highly specific for the diagnosis of MOGAD. This review will highlight the key clinical and radiological features which expedite diagnosis, as well as ancillary investigations such as visual fields, visual evoked potentials and cerebrospinal fluid analysis, which may be less discriminatory. Optical coherence tomography can identify optic nerve swelling acutely, and atrophy chronically, and may transpire to have utility as a diagnostic and prognostic biomarker. MOG-ON appears to be largely responsive to corticosteroids, which are often the mainstay of acute management. However, relapses are common in patients in whom follow-up is prolonged, often in the context of early or rapid corticosteroid tapering. Establishing optimal acute therapy, the role of maintenance steroid-sparing immunotherapy for long-term relapse prevention, and identifying predictors of relapsing disease remain key research priorities in MOG-ON.

Oral corticosteroid dosage and taper duration at onset in myelin oligodendrocyte glycoprotein antibody-associated disease influences time to first relapse.

BACKGROUND: We sought to identify an optimal oral corticosteroid regimen at the onset of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), which would delay time to first relapse while minimising cumulative corticosteroid exposure. METHODS: In a retrospective multicentre cohort study, Cox proportional hazards models examined the relationship between corticosteroid course as a time-varying covariate and time to first relapse. Simon-Makuch and Kaplan-Meier plots identified an optimal dosing strategy. RESULTS: We evaluated 109 patients (62 female, 57%; 41 paediatric, 38%; median age at onset 26 years, (IQR 8-38); median follow-up 6.2 years (IQR 2.6-9.6)). 76/109 (70%) experienced a relapse (median time to first relapse 13.7 months; 95% CI 8.2 to 37.9). In a multivariable model, higher doses of oral prednisone delayed time to first relapse with an effect estimate of 3.7% (95% CI 0.8% to 6.6%; p=0.014) reduced hazard of relapse for every 1 mg/day dose increment. There was evidence of reduced hazard of relapse for patients dosed ≥12.5 mg/day (HR 0.21, 95% CI 0.07 to 0.6; p=0.0036), corresponding to a 79% reduction in relapse risk. There was evidence of reduced hazard of relapse for those dosed ≥12.5 mg/day for at least 3 months (HR 0.12, 95% CI 0.03 to 0.44; p=0.0012), corresponding to an 88% reduction in relapse risk compared with those never treated in this range. No patient with this recommended dosing at onset experienced a Common Terminology Criteria for Adverse Events grade >3 adverse effect. CONCLUSIONS: The optimal dose of 12.5 mg of prednisone daily in adults (0.16 mg/kg/day for children) for a minimum of 3 months at the onset of MOGAD delays time to first relapse.

Model discovery approach enables noninvasive measurement of intra-tumoral fluid transport in dynamic MRI.

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a routine method to noninvasively quantify perfusion dynamics in tissues. The standard practice for analyzing DCE-MRI data is to fit an ordinary differential equation to each voxel. Recent advances in data science provide an opportunity to move beyond existing methods to obtain more accurate measurements of fluid properties. Here, we developed a localized convolutional function regression that enables simultaneous measurement of interstitial fluid velocity, diffusion, and perfusion in 3D. We validated the method computationally and experimentally, demonstrating accurate measurement of fluid dynamics in situ and in vivo. Applying the method to human MRIs, we observed tissue-specific differences in fluid dynamics, with an increased fluid velocity in breast cancer as compared to brain cancer. Overall, our method represents an improved strategy for studying interstitial flows and interstitial transport in tumors and patients. We expect that our method will contribute to the better understanding of cancer progression and therapeutic response.

Structural and practical identifiability of contrast transport models for DCE-MRI.

Contrast transport models are widely used to quantify blood flow and transport in dynamic contrast-enhanced magnetic resonance imaging. These models analyze the time course of the contrast agent concentration, providing diagnostic and prognostic value for many biological systems. Thus, ensuring accuracy and repeatability of the model parameter estimation is a fundamental concern. In this work, we analyze the structural and practical identifiability of a class of nested compartment models pervasively used in analysis of MRI data. We combine artificial and real data to study the role of noise in model parameter estimation. We observe that although all the models are structurally identifiable, practical identifiability strongly depends on the data characteristics. We analyze the impact of increasing data noise on parameter identifiability and show how the latter can be recovered with increased data quality. To complete the analysis, we show that the results do not depend on specific tissue characteristics or the type of enhancement patterns of contrast agent signal.