👤 Sithara Ramdas

Congenital myasthenic syndromes (CMS) are often underdiagnosed due to phenotypic overlap with other neuromuscular disorders. Limited epidemiological data and low awareness hinder early diagnosis, which is key for effective treatment. Early recognition of CMS is important as symptomatic treatments often specific for genetic subtypes exist and emerging therapies are in the pipeline. This study aims to estimate the prevalence of genetically confirmed CMS in the United Kingdom and explore geographical variations. Prevalence was calculated as of 31 December 2023, including genetically confirmed CMS patients residing in the United Kingdom and known to be alive. Patients with missing geographic or living status data were excluded. Prevalence was estimated overall and compared between UK regions served by a highly specialized neuromuscular service (hsNMS) and those without such services (non-hsNMS). A cohort of 442 genetically confirmed CMS patients was identified. CHRNE deficiency, DOK7, RAPSN were the most common subtypes. The UK prevalence was 6.5 cases per million overall and 8.5 cases per million in the pediatric population. The overall prevalence was statistically higher in hsNMS (8.8 cases per million) compared to non-hsNMS regions (5.9 cases per million). Homozygous patients had a more clustered distribution particularly around urban area. Our results suggest there is likely underdiagnosis of CMS in many areas of the United Kingdom and hsNMS may play an important diagnostic role. Variations may also be related to other cultural clustering and founder effects. Further research should explore how healthcare access, ethnicity, and consanguinity contribute to regional variation and diagnostic rates. Show less

Three-dimensional (3D) spheroid models are increasingly used to emulate the tumour microenvironment for preclinical drug screening. This study aimed to optimise and assess spheroid formation from MDA-MB-468 triple-negative breast cancer (TNBC) cells using hanging drop, liquid overlay, and rigid scaffold methods under normal oxygen (NOC) and low oxygen (LOC) culture conditions. Spheroids were generated and characterised using bright-field microscopy with AnaSP morphometrics (sphericity, solidity, and perimeter). Gene expression of Epithelial-Mesenchymal Transition (EMT), stemness, and hypoxia/angiogenesis markers (CD44, HIF1A, VEGFA, TWIST1, SNAI1, and NES) was quantified using qPCR. The optimised model was further evaluated using field-emission scanning electron microscopy (FE-SEM) and Hoechst fluorescence. A workflow combining hanging-drop pre-aggregation with ultra-low attachment (ULA) or agarose-coated plates under NOC produced consistent, compact spheroids. Scaffold cultures formed rapidly but showed size variability under NOC and LOC. Across methods, spheroids were less compact, and gene expression patterns deviated from expected hypoxic responses. Spheroids cultivated under normoxic conditions demonstrated enhanced structural integrity and transcriptional fidelity. Nonetheless, the study identified that the most compact and resilient spheroids were achieved through the use of hanging-drop pre-aggregation combined with ULA-plates under NOC. The enhanced structural integrity and transcriptional fidelity observed in these spheroids make them valuable models for studying cancer biology and drug responses. The online version contains supplementary material available at 10.1007/s11033-026-11451-4. Show less

Congenital Myasthenic Syndromes (CMS) are a group of inherited disorders characterised by fatigable muscle weakness. There are currently no validated outcome measures in CMS. We conducted a prospective exploratory observational study in 49 CMS patients. The primary aim was to explore relevant and reliable outcome measures for assessing and monitoring change. Assessments included Quantitative Myasthenia Gravis score, Myasthenia Gravis Activities of Daily Living, six-minute-walk-test and sit to stand in one minute, in addition to others. Patients were seen 2-4 times over a 2-year period. Median age was 25.5 (range 1-72) years. Subtypes included AChR-deficiency (n = 15), AGRN-DOK7 clustering complex (n = 15), RAPSN (n = 6), COLQ (n = 5), others (n = 8). Ptosis was highest in AChR-deficiency and limb fatigue was highest in AGRN-DOK7 and COLQ. Median sit to stand in one minute was 22 (range 6-45), median total distance walked in six-minute-walk-test was 434 metres (range 0-711 m). A correlation was noted between sit to stand and six-minute-walk-test (R² = 0.291, p-value <0.001) and between total Quantitative Myasthenia Gravis and Myasthenia Gravis Activities of Daily Living scores (R² = 0.2851, p-value <0.001). This is the first study exploring the use of outcome measures in a CMS population, highlighting the variability in fatigue across CMS subtypes and the limitations of outcome measures validated in myasthenia gravis for CMS. Show less

Stroke embolic source have an unknown origin in 30-40% of cases. Mechanical thrombectomy for acute large vessel occlusion stroke has provided us with a method to directly retrieve the thrombi from patients for analysis. By collecting stroke-causing thrombi from known sources, we can then use high-throughput RNA sequencing (RNAseq) technology to directly measure the gene expression signatures of these clots. This may allow us to identify genetic markers to predict the cause of cryptogenic embolism. This is a prospective study in which RNAseq was used to analyze cerebral thrombi retrieved by mechanical thrombectomy devices in acute ischemic stroke patients. Samples were separated into two groups based on known stroke thrombus etiology, including Carotid group (patients with ipsilateral >70% carotid stenosis) and Atrial fibrillation (AF) group (patients with atrial fibrillation). Gene expression was compared by RNAseq analysis between the groups. From October 2016 to September 2017, 8 thrombi (4 in Carotid group, 4 in Afib group) were included in this study. There were 131 genes that were significantly up- or down-regulated between the two groups defined as a false discovery rate ≤ 0.05 and a fold change ≥ 2. Twenty-six genes were selected as candidate gene biomarkers based on the criteria in the methods section. Candidate genes HSPA1B, which encodes a heatshock protein, and GPRC5B, which encodes a G-protein, showed the greatest fold differences in expression between the two groups. This study has shown that RNA sequencing of acute ischemic stroke thrombi is feasible and indentified potential novel biomarkers for identifying stroke-causing thrombi origin, especially in cryptogenic stroke. Show less

Respiratory problems are a major cause of morbidity and mortality in patients with congenital myasthenic syndromes, a rare heterogeneous group of neuromuscular disorders caused by genetic defects impacting the structure and function of the neuromuscular junction. Recurrent, life-threatening episodic apnoea in early infancy and childhood and progressive respiratory failure requiring ventilation are features of certain genotypes of congenital myasthenic syndromes. Robb Show less