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1.
iScience ; 27(5): 109768, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38711441

RESUMO

Spinocerebellar Ataxia type-12 (SCA12) is a neurodegenerative disease caused by tandem CAG repeat expansion in the 5'-UTR/non-coding region of PPP2R2B. Molecular pathology of SCA12 has not been studied in the context of CAG repeats, and no appropriate models exist. We found in human SCA12-iPSC-derived neuronal lineage that expanded CAG in PPP2R2B transcript forms nuclear RNA foci and were found to sequester variety of proteins. Further, the ectopic expression of transcript containing varying length of CAG repeats exhibits non-canonical repeat-associated non-AUG (RAN) translation in multiple frames in HEK293T cells, which was further validated in patient-derived neural stem cells using specific antibodies. mRNA sequencing of the SCA12 and control neurons have shown a network of crucial transcription factors affecting neural fate, in addition to alteration of various signaling pathways involved in neurodevelopment. Altogether, this study identifies the molecular signatures of SCA12 disorder using patient-derived neuronal cell lines.

3.
Cereb Cortex ; 34(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38679476

RESUMO

Spinocerebellar ataxia type 12 is a hereditary and neurodegenerative illness commonly found in India. However, there is no established noninvasive automatic diagnostic system for its diagnosis and identification of imaging biomarkers. This work proposes a novel four-phase machine learning-based diagnostic framework to find spinocerebellar ataxia type 12 disease-specific atrophic-brain regions and distinguish spinocerebellar ataxia type 12 from healthy using a real structural magnetic resonance imaging dataset. Firstly, each brain region is represented in terms of statistics of coefficients obtained using 3D-discrete wavelet transform. Secondly, a set of relevant regions are selected using a graph network-based method. Thirdly, a kernel support vector machine is used to capture nonlinear relationships among the voxels of a brain region. Finally, the linear relationship among the brain regions is captured to build a decision model to distinguish spinocerebellar ataxia type 12 from healthy by using the regularized logistic regression method. A classification accuracy of 95% and a harmonic mean of precision and recall, i.e. F1-score of 94.92%, is achieved. The proposed framework provides relevant regions responsible for the atrophy. The importance of each region is captured using Shapley Additive exPlanations values. We also performed a statistical analysis to find volumetric changes in spinocerebellar ataxia type 12 group compared to healthy. The promising result of the proposed framework shows that clinicians can use it for early and timely diagnosis of spinocerebellar ataxia type 12.


Assuntos
Biomarcadores , Encéfalo , Imageamento por Ressonância Magnética , Ataxias Espinocerebelares , Máquina de Vetores de Suporte , Humanos , Imageamento por Ressonância Magnética/métodos , Ataxias Espinocerebelares/diagnóstico por imagem , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/diagnóstico , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/metabolismo , Biomarcadores/análise , Masculino , Feminino , Adulto , Modelos Logísticos , Pessoa de Meia-Idade , Atrofia
5.
IEEE Trans Haptics ; PP2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526896

RESUMO

Auditory and visual cues have been efficacious in laboratory-based freezing of gait (FoG) mitigation in Parkinson's disease (PD). However, real-life applications of these cues are restricted due to inconvenience to the users. Closed-loop vibrotactile cues based on temporal gait events have overcome the shortcomings of auditory and visual cueing. However, kinematic gait parameter-driven vibrotactile cueing has not been explored yet. Kinematic gait parameter-driven cueing is more effective than temporal cueing, according to FoG pathophysiology studies. Therefore, we developed and pilot-tested a novel cueing scheme in which the foot-to-ground angle at heel strike (FGA_HS) is estimated using indigenous instrumented shoes to drive vibrotactile cueing. Ten PD freezers underwent a 6-meter timed walk test in the off-medication state with and without the cue and after medication without the cue. The proposed system potentially mitigated FoG, quantified by a reduction in the ratio of time spent freezing to the total walking time and the number of FoGs. The FoG mitigation potential of the cue was further supported by increased anteroposterior center of pressure progression and FGA_HS. With a future comprehensive validation in a larger number of participants, the novel cue could likely be used in practice and commercialized.

6.
Epilepsy Behav ; 153: 109703, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38452517

RESUMO

BACKGROUND: Neuropsychological Rehabilitation (NR) helps manage cognitive deficits in epilepsy. As internationally developed programs have limited applicability to resource-limited countries, we developed a program to bridge this gap. This 6-week caregiver-assisted, culturally suitable program has components of (1) psychoeducation, (2) compensatory training, and, (3) cognitive retraining and is called EMPOWER (Indigenized Home Based Attention and Memory Rehabilitation Program for Adult Patients with Drug Refractory Epilepsy). Its efficacy needs to be determined. METHODS: We carried out an open-label parallel randomized controlled trial. Adults aged 18-45 years with Drug Refractory Epilepsy (DRE), fluency in Hindi and or English, with impaired attention or memory (n = 28) were randomized to Intervention Group (IG) and Control Group (CG). The primary outcomes were objective memory (Auditory Verbal Learning Test), patient and caregiver reported everyday memory difficulties (Everyday Memory Questionnaire-Revised), number of memory aids in use, depression (Hamilton Depression Rating Scale), anxiety (Hamilton Anxiety Rating Scale) and quality of life (Quality of Life in Epilepsy-31). Intention to treat was carried out for group analysis. In the absence of norms necessary for computing Reliable Change Indices (RCIs), a cut-off of +1.0 Standard Deviation (SD) was utilized to identify clinically meaningful changes in the individual analysis of objective memory. A cut-off of 11.8 points was used for quality of life. Feedback and program evaluation responses were noted. RESULTS: The majority of the sample comprised DRE patients with temporal lobe epilepsy who had undergone epilepsy surgery. Group analysis indicated improved learning (p = 0.013), immediate recall (p = 0.001), delayed recall (p < 0.001), long-term retention (p = 0.031), patient-reported everyday memory (p < 0.001), caregiver-reported everyday memory (p < 0.001), anxiety (p = 0.039) and total quality of life (p < 0.001). Individual analysis showed improvement in 50 %, 64 %, 71 %, 57 %, and 64 % of patients on learning, immediate recall, delayed recall, long-term retention, and total quality of life respectively. Despite improvements, themes indicative of a lack of awareness and understanding of cognitive deficits were identified. Overall, the program was rated favorably by patients and caregivers alike. CONCLUSION: NR shows promise for patients with DRE, however larger studies are warranted. The role of cognition in epilepsy needs to be introduced at the time of diagnosis to help lay the foundation for education and acceptance.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Adulto , Humanos , Qualidade de Vida/psicologia , Testes Neuropsicológicos , Epilepsia/psicologia , Memória de Curto Prazo
12.
Stem Cell Res ; 77: 103382, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38484450

RESUMO

Friedreich's ataxia is a spinocerebellar degenerative disease caused by microsatellite (GAA.TTC)n repeat expansion in the first intron of FXN gene. Here, we developed iPSC lines from an FRDA patient (IGIBi016-A) and non-FRDA healthy control (IGIBi017-A). Both iPSC lines displayed typical iPSC morphology, expression of pluripotency markers, regular karyotypes (46, XY; 46, XX), capacity to grow into three germ layers, and FRDA hallmark -GAA repeat expansion and decreased FXN mRNA. Through these iPSC lines, FRDA phenotypes may be replicated in the in vitro assays, by creating neuron subtypes, cardiomyocytes and 3D organoids, for molecular and cellular biomarkers and therapeutic applications.

14.
Stem Cell Res ; 76: 103319, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38340452

RESUMO

The PPP2R2B gene, expressed highly in the brain, harbours trinucleotide CAG repeats in the 5'UTR region, in the range of 7-42 repeats. Individuals carrying CAG repeats greater than 43 have been associated to manifest a neurodegenerative disease condition termed as Spinocerebellar Ataxia type 12 (SCA12). An iPSC line from an adult male diagnosed with SCA12 presenting symptoms of gait (Gait Dominance) was generated. It showed pluripotency and trilineage markers without any chromosomal abnormality. This line can be utilized as an essential resource in enhancing our understanding of the molecular pathogenic mechanisms underlying SCA12 by facilitating generation of various neuronal cell types.


Assuntos
Células-Tronco Pluripotentes Induzidas , Ataxias Espinocerebelares , Adulto , Humanos , Masculino , Células-Tronco Pluripotentes Induzidas/metabolismo , Ataxias Espinocerebelares/patologia , Neurônios , Repetições de Trinucleotídeos
15.
Stem Cell Res ; 76: 103340, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367363

RESUMO

Friedreich's ataxia is a neurodegenerative disorder caused by the hyper expansion of (GAA-TTC)n triplet repeats in the first intron of the FXN gene. Here, we generated iPSC lines from two individuals with FRDA, both of whom have homozygous GAA repeat expansion in the first intron of FXN gene. Both iPSC lines demonstrated characteristics of pluripotency, including expression of pluripotency markers, stable karyotypes and ability to develop into all three germ layers, and presence of GAA repeat expansion with reduced FXN mRNA expression. These iPSC lines will serve as invaluable tools for investigating the pathophysiology and phenotypes of FRDA.


Assuntos
Ataxia de Friedreich , Células-Tronco Pluripotentes Induzidas , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Ataxia de Friedreich/genética , Ataxia de Friedreich/metabolismo , Expansão das Repetições de Trinucleotídeos/genética , Íntrons
16.
Sci Rep ; 14(1): 4718, 2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413676

RESUMO

Primary CNS Vasculitis (PCNSV) is a rare, diverse, and polymorphic CNS blood vessel inflammatory condition. Due to its rarity, clinical variability, heterogeneous imaging results, and lack of definitive laboratory markers, PCNSV diagnosis is challenging. This retrospective cohort analysis identified patients with histological diagnosis of PCNSV. Demographic data, clinical presentation, neuroimaging studies, and histopathologic findings were recorded. We enrolled 56 patients with a positive biopsy of CNS vasculitis. Most patients had cerebral hemisphere or brainstem symptoms. Most brain MRI lesions were bilateral, diffuse discrete to confluent white matter lesions. Frontal lobe lesions predominated, followed by inferior cerebellar lesions. Susceptibility-weighted imaging (SWI) hemorrhages in 96.4% (54/56) of patients, either solitary microhemorrhages or a combination of micro and macrohemorrhages. Contrast-enhanced T1-WIs revealed parenchymal enhancement in 96.3% (52/54 patients). The most prevalent pattern of enhancement observed was dot-linear (87%), followed by nodular (61.1%), perivascular (25.9%), and patchy (16.7%). Venulitis was found in 19 of 20 individuals in cerebral DSA. Hemorrhages in SWI and dot-linear enhancement pattern should be incorporated as MINOR diagnostic criteria to diagnose PCNSV accurately within an appropriate clinical context. Microhemorrhages in SWI and venulitis in DSA, should be regarded as a potential marker for PCNSV.


Assuntos
Imageamento por Ressonância Magnética , Vasculite do Sistema Nervoso Central , Humanos , Estudos Retrospectivos , Estudos de Coortes , Vasculite do Sistema Nervoso Central/diagnóstico por imagem , Vasculite do Sistema Nervoso Central/patologia , Hemorragia
18.
Mov Disord Clin Pract ; 11(2): 136-142, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38386479

RESUMO

BACKGROUND: The merits of classifying the heterogeneous group of essential tremors into essential tremor (ET) and essential tremor plus (ETP) are debated. OBJECTIVES: We studied the electrophysiological and spiral characteristics of tremor in ET and ETP. METHODS: We reviewed standardized videos from a tremor database and clinically classified patients into ET, ETP, or dystonic tremor (DT). The following variables were derived from combined tri-axial accelerometry-surface electromyography (EMG)-peak frequency, total power, peak power, full width half maximum, tremor stability index and EMG-coherence. We analyzed hand-drawn spirals to derive mean deviation, tremor variability, inter-, and intra-loop widths. We compared these variables among the groups. RESULTS: We recruited 72 participants (81.9% male) with mean age 47.7 ± 16.1 years and Fahn-Tolosa-Marin Tremor Rating Scale total score 31.1 ± 14.1. Patients with ET were younger (P = 0.014) and had less severe tremor (P = 0.020) compared to ETP and DT. In ETP group, 48.6% had subtle dystonia. Peak frequency was greater in ETP (7.3 ± 0.3 Hz) compared to DT (6.1 ± 0.4 Hz; P = 0.024). Peak power was greater in ETP and DT for postural tremor. Rest tremor was recordable on accelerometry in 26.7% of ET. Other variables were similar among the groups. CONCLUSION: Electrophysiological evaluation revealed postural tremor of frequency 6 to 7 Hz in ET, ETP, and DT with subtle differences more severe tremor in ETP and DT, and higher frequency in ETP compared to DT. Our findings suggest a similar tremor oscillator in these conditions, supporting the view that these entities are part of a spectrum of tremor disorders, rather than distinct etiological entities.


Assuntos
Distonia , Distúrbios Distônicos , Tremor Essencial , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distonia/complicações , Distúrbios Distônicos/complicações , Eletromiografia , Tremor Essencial/diagnóstico
19.
Pract Neurol ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38423753

RESUMO

A 25-year-old woman presented with 1 year of progressive orthopnoea, initially explained as bilateral diaphragmatic paresis caused by seronegative myasthenia gravis. She required assisted ventilation and received pyridostigmine and corticosteroids. She had minimal (particularly proximal) symmetrical tetraparesis with apparent bilateral diaphragmatic weakness, but had normal sensation. Further investigation suggested an overlap myositis with shrinking lung syndrome from systemic lupus erythematosus. She improved following immunosuppression with pulse corticosteroids and rituximab, and at 3 months no longer needed bilevel positive airway pressure support.

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