Diagnostic Value of Structural MRI in Spinocerebellar Ataxia Type 3 / 中山大学学报(医学科学版)

ObjectiveTo explore the role of structural MRI in the diagnosis of spinocerebellar ataxia type 3 （SCA3） and further evaluate its correlation with disease severity and disease duration. MethodsWe prospectively enrolled 81 genetically diagnosed SCA3 patients ［59 symptomatic （sym-SCA3） and 22 pre-symptomatic （pre-SCA3）］ and 35 age- and sex-matched healthy controls （HCs）. MRI structural images （3D T1 MPRAGE） and clinical data of all subjects were collected. Three observers with different radiological experience measured the width of the superior， middle and inferior cerebellar peduncle （SCP， MCP and ICP）， the anterior-posterior diameters of the pons and spinal cord at the levels of the foramen magnum and upper edge of the 3rd-5th cervical vertebra. One observer performed the measurements again 2 months later to assess for the intra- and inter-observer reliability， respectively. One-way ANOVA， rank-sum test， ROC curve and Random Forest were used to evaluate the diagnostic value of the above metrics for SCA3， and the correlation between the metrics and clinical variables was analyzed. ResultsNot depending on the radiological experience， the metrics based on morphological MRI showed high intra- and inter-observer reliability， among which bilateral superior and middle cerebellar peduncles performed best. The diameters of bilateral SCP， MCP， ICP， pons and spinal cord （except spinal cord at the level of the upper edge of the 5th cervical vertebra） decreased successively in HCs， pre-SCA3 and sym-SCA3 with a statistical difference （P<0.017）. ROC analysis revealed that the left MCP had the highest diagnostic value for pre-SCA3 （AUC=0.911）， with sensitivity， specificity and a cut-off value of 85.7%， 95.5% and 10.15 mm， respectively. In contrast， the right SCP had the highest diagnostic value for sym-SCA3 （AUC=0.999）， with sensitivity， specificity and a cut-off value of 100%， 98.3% and 2.62 mm， respectively. The Random Forest model based on the above metrics also had high diagnostic efficiency （AUC= 0.970， specificity=93.1%）， and the left MCP contributed the most. Correlation analysis showed that the above metrics had a significantly or moderately negative correlation with the Scale for the Assessment and Rating of Ataxia （SARA） and disease duration （P<0.05）. ConclusionNot depending on radiological experience， measurements of brain structure based on morphological MRI are reliable， which can help diagnose SCA3 and predict disease severity and duration. The left MCP and the right SCP perform best for predicting pre-SCA3 and sym-SCA3， respectively. Therefore， the structural MRI is recommended for assisting the clinical diagnosis of SCA3.

Effects of NaHS on MBP and learning and memory in hippocampus of mice with spinocerebellar ataxia / 中国应用生理学杂志

To investigate the effects of exogenous NaHS on myelin basic protein (MBP) and learning and memory of hippocampal neurons in mice with spinocerebellar ataxia type 3 (SCA3) and its therapeutic significance. Twelve male normal mice were randomly selected as normal control group (NC Group), and 48 SCA3 mice were randomly selected as SCA3 model group (M Group), low dose group (NL Group, 10 μmol/kg), medium dose group (NM Group, 50μmol/kg) and high dose group (NH Group, 100 μmol/kg), 12 rats in each group. The drug treated groups were injected with NaHS intraperitoneally once a day for 4 weeks. The changes of learning and memory ability of SCA3 mice before and after the intervention of different doses of NaHS were determined by Morris water maze, the content of hydrogen sulfide (HS) in hippocampus was measured by spectrophotometry, the expression of MBP was detected by immunohistochemistry, and the morphological changes of neuron myelin sheath were observed by electron microscope. Compared with the control group, the learning and memory ability of SCA3 mice was decreased significantly (P＜0.05), and the content of HS in hippocampus was decreased (P＜0.05). After different doses of exogenous NaHS treatment, the learning and memory ability was improved in different degrees (P＜0.05), and the contents of HS and MBP in hippocampus of SCA3 mice were also improved in different degrees (P＜0.05). Exogenous NaHS may increase the contents of HS and MBP in the hippocampus of SCA3 mice, which may have a protective effect on the neurons, and then improve the learning and memory ability of SCA3 mice, and provide a new idea for the treatment of SCA3.

Atuação fonoaudiológica na doença de Machado-Joseph: relato de caso / Effect of speech-language therapy in Machado-Joseph disease: case report

RESUMO A doença de Machado-Joseph é a forma de ataxia espinocerebelar de maior prevalência no Brasil e tem como alguns dos principais sinais clínicos a disfagia e a disartria. Este relato de caso objetivou verificar os efeitos da intervenção intensiva fonoaudiológica em um paciente com a doença de Machado-Joseph. A coleta de dados foi realizada a partir de protocolos de avaliação de fala e deglutição e protocolos de autoavaliação de qualidade de vida, em relação à deglutição e comunicação. Também foram realizadas avaliações quantitativas de parâmetros acústicos. A intervenção foi administrada por meio do método Lee Silverman, programa intensivo que visa ao aumento da intensidade vocal. A partir das avaliações clínicas e instrumentais, os resultados demonstraram melhora em todas as bases motoras de fala, respiratória, fonatória, ressonantal, articulatória e a prosódia, além da diminuição dos sinais disfágicos. Na qualidade vocal, houve diminuição de rouquidão e instabilidade, regularização de jitter e shimmer, aumento da intensidade vocal, melhora na coordenação de palavras e frases por expiração e, ainda, melhora discreta da diadococinesia. Após intervenção, a autoavaliação de qualidade de vida relacionada à deglutição apresentou valores iguais ou maiores nos domínios diretamente ligados à alimentação, porém, os domínios emocionais diminuíram. O paciente relatou satisfação em todos os domínios da qualidade de vida em voz e foram obtidos valores maiores em todos os domínios. Concluiu-se que a intervenção intensiva beneficiou o participante e impactou positivamente sua qualidade de vida.

ABSTRACT Machado-Joseph disease is the most prevalent form of spinocerebellar ataxia in Brazil, and has dysphagia and dysarthria among its main clinical signs. This case report aims to ascertain the effects of intensive speech-language intervention in a patient with Machado-Joseph disease. Data collection was performed based on speech and swallowing assessment protocols and self-assessment protocols specific to swallowing-related and communication-related quality of life. Quantitative assessments of acoustic parameters were also performed. The intervention was administered through the Lee Silverman method, which is an intensive program aimed at increasing vocal intensity. The results of clinical and instrumental evaluations showed improvement in all motor parameters of speech (respiration, phonation, resonance, articulation, and prosody), besides a reduction in dysphagic signs. Regarding vocal quality, there was a decrease in hoarseness and instability, regularization of jitter and shimmer, increased vocal intensity, and improved coordination of words and phrases by expiration, as well as slight improvement of diadochokinesis. After intervention, self-assessment of swallowing-related quality of life was unchanged or improved in the domains directly related to food, but reduced in emotional domains. The patient reported satisfaction in all domains of voice-related quality of life, and scores were increased in all domains. We conclude that intensive intervention was beneficial for the participant and positively impacted their quality of life.

Amplio espectro fenotípico de la SCA-3: paraparesia espástica hereditaria / The broad phenotypic spectrum of SCA-3: hereditary spastic paraplegia

La ataxia espinocerebelosa tipo 3 o enfermedad de Machado-Joseph (SCA-3/EMJ) es la forma más frecuente de ataxia espinocerebelosa autosómica dominante. Se caracteriza por una marcada variabilidad fenotípica, pudiendo causar formas no cerebelosas de presentación. En base a algunos casos comunicados, se ha propuesto una forma de presentación clínica similar a la de una paraparesia espástica hereditaria, con la presencia de signos de disfunción piramidal predominantes como la manifestación clínica inicial. Presentamos dos nuevos casos de SCA-3/EMJ con un cuadro clínico inicial sugerente de paraparesia espástica hereditaria y una revisión de los casos clínicos similares previamente informados. Nuestros hallazgos apoyan la propuesta de un subtipo de SCA-3/EMJ caracterizado por la presencia de marcada disfunción piramidal como manifestación inicial, simulando un cuadro clínico de paraparesia espástica hereditaria.

Machado-Joseph disease (MJD) is the most frequent dominantly inherited spinocerebellar ataxia. A marked phenotypic variability is a characteristic of this disorder that could involve non-cerebellar presentations. Based on several case reports describing pyramidal dysfunction as the main symptom at onset, a clinical form resembling hereditary spastic paraplegia has been proposed. We report here two further cases of MJD patients whose initial clinical presentation suggested hereditary spastic paraplegia, and a summary of the main findings of previously similar published reports. Our findings lent support to the proposal of a MJD subtype distinguished by a marked pyramidal dysfunction at onset, simulating a clinical picture of hereditary spastic paraplegia.

Spinocerebellar ataxias: genotype-phenotype correlations in 104 Brazilian families

OBJECTIVE: Spinocerebellar ataxias are neurodegenerative disorders involving the cerebellum and its connections. There are more than 30 distinct subtypes, 16 of which are associated with an identified gene. The aim of the current study was to evaluate a large group of patients from 104 Brazilian families with spinocerebellar ataxias. METHODS: We studied 150 patients from 104 families with spinocerebellar ataxias who had received molecular genetic testing for spinocerebellar ataxia types 1, 2, 3, 6, 7, 8, 10, 12, 17, and dentatorubral-pallidoluysian atrophy. A statistical analysis of the results was performed using basic descriptive statistics and the correlation coefficient (r), Student's t-test, chi-square test, and Yates' correction. The statistical significance level was established for p-values <0.05. RESULTS: The results show that the most common subtype was spinocerebellar ataxia 3, which was followed by spinocerebellar ataxia 10. Moreover, the comparison between patients with spinocerebellar ataxia 3, spinocerebellar ataxia 10, and other types of spinocerebellar ataxia revealed distinct clinical features for each type. In patients with spinocerebellar ataxia 3, the phenotype was highly pleomorphic, although the most common signs of disease included cerebellar ataxia (CA), ophthalmoplegia, diplopia, eyelid retraction, facial fasciculation, pyramidal signs, and peripheral neuropathy. In patients with spinocerebellar ataxia 10, the phenotype was also rather distinct and consisted of pure cerebellar ataxia and abnormal saccadic eye movement as well as ocular dysmetria. Patients with spinocerebellar ataxias 2 and 7 presented highly suggestive features of cerebellar ataxia, including slow saccadic ocular movements and areflexia in spinocerebellar ataxia 2 and visual loss in spinocerebellar ataxia 7. CONCLUSIONS: Spinocerebellar ataxia 3 was the most common subtype examined, followed by spinocerebellar ataxia 10. Patients with spinocerebellar ataxia 2 and 7 demonstrated highly suggestive features, whereas the phenotype of spinocerebellar ataxia 3 patients was highly pleomorphic and spinocerebellar ataxia 10 patients exhibited pure cerebellar ataxia. Epilepsy was absent in all of the patients with spinocerebellar ataxia 10 in this series.

Brain stem and cerebellum volumetric analysis of Machado Joseph disease patients / Análise volumétrica de cerebelo e tronco cerebral de pacientes com doença de Machado Joseph

Machado-Joseph disease, or spinocerebellar ataxia type 3(MJD/SCA3), is the most frequent late onset spinocerebellar ataxia and results from a CAG repeat expansion in the ataxin-3 gene. Previous studies have found correlation between atrophy of cerebellum and brainstem with age and CAG repeats, although no such correlation has been found with disease duration and clinical manifestations. In this study we test the hypothesis that atrophy of cerebellum and brainstem in MJD/SCA3 is related to clinical severity, disease duration and CAG repeat length as well as to other variables such as age and ICARS (International Cooperative Ataxia Rating Scale). Whole brain high resolution MRI and volumetric measurement with cranial volume normalization were obtained from 15 MJD/SCA3 patients and 15 normal, age and sex-matchedcontrols. We applied ICARS and compared the score with volumes and CAG number, disease duration and age. We found significant correlation of both brain stem and cerebellar atrophy with CAG repeat length, age, disease duration and degree of disability. The Spearman rank correlation was stronger with volumetric reduction of the cerebellum than with brain stem. Our data allow us to conclude that volumetric analysis might reveal progressive degeneration after disease onset, which in turn is linked to both age and number of CAG repeat expansions in SCA 3.

Doença de Machado-Joseph, ou ataxia espinocerebelar tipo 3 (MJD/SCA3) é ataxia espinocerebelar de início tardio mais frequente e resulta de uma expansão da repetição CAG no gene da ataxina-3. Estudos precedentes encontraram correlação entre a atrofia do cerebelo e do tronco cerebral com a idade e número de expansões CAG. Tais correlações não foram encontradas em relação ao tempo de doença ou manifestações clínicas. Neste estudo testamos a hipótese de que a atrofia do cerebelo e do tronco encefálico em MJD/SCA3 está relacionada à gravidade clínica, duração da doença e número de repetições CAG, bem como com outras variáveis como a idade e a ICARS (escala cooperativa internacional de avaliação de ataxias). Foram realizados estudos de imagem pela ressonância magnética de alta resolução e volumetria com normalização de volume craniano de 15 pacientes portadores de MJD/SCA3 e 15 controles pareados por idade e sexo. Nós aplicamos a ICARS e correlacionamos com o escore de volumes e número de CAG, duração da doença e idade. Encontramos correlação significativa entre atrofia de tronco cerebral e cerebelo com duração da doença, repetição CAG, idade e grau de acometimento da doença. O índice de correlação de Spearman foi maior em relação à atrofia de cerebelo do que à atrofia de tronco. Nossos dados permitem concluir que a análise volumétrica pode revelar degeneração progressiva após o início da doença que, por sua vez, está ligada à idade e número de expansões CAG em SCA 3.

Trinucleotide Repeats Number in SCA2, SCA3, and SCA17 in Early-Onset Parkinson's Disease

BACKGROUND: Abnormal expansion of trinucleotide repeats in genes causing spinocerebellar ataxias such as SCA2, SCA3, SCA8, or SCA17 was reported in sporadic or familial Parkinson's disease. Genetic factors play an important role especially in early-onset Parkinson's disease (EOPD). To investigate mutations of ATXN2, ATXN3, and TBP as a possible cause in Korean EOPD, we analyzed mutations in these genes. We also investgated the possibility that trinucleotide repeats numbers in these genes contribute to the development of EOPD. METHODS: Mutation analysis of ATXN2, ATXN3, and TBP was done in 153 EOPD defined as age-at-onset before 51. Distribution of CAG repeats numbers were compared between EOPD and age- and sex-matched controls. RESULTS: No patients with EOPD had CAG repeats numbers in ATXN2, ATXN3, and TBP in mutation range. There was no difference in the distribution of CAG repeats between EOPD and controls, although we found a trend that CAG repeats numbers in ATXN3 appear larger in EOPD than in controls. CONCLUSIONS: Mutations of genes causing SCA2, SCA3, or SCA17 may not be a common genetic cause in Korean EOPD.

Expression of Expanded Polyglutamine Disease Proteins in Drosophila (Drosophila Polyglutamine Disease Models) / 소아과

PURPOSE: Polyglutamine diseases are a group of diseases caused by the expansion of a polyglutamine tract in the protein. The present study was performed to verify if polyglutamine disease transgenic Drosophila models show similar dysfunctions as are seen in human patients. METHODS: Polyglutamine disease transgenic Drosophila were tested for their climbing ability. And using genetic methods, the effects of anti-apoptotic gene bcl-2 and chemical chaperones on neurodegeneration were observed. Also, spinocerebellar ataxia 2 (SCA2) transgenic Drosophila lines were generated for future studies. RESULTS: Expanded forms of spinocerebellar ataxia 3 (SCA3) transgenic protein causes characteristic locomotor dysfunction when expressed in the nervous system of Drosophila but the anti-apoptotic gene bcl-2 shows no evidence of ameliorating the deleterious effect of the expanded protein. However, Glycerol, a chemical chaperone, seemed to reduce the toxicity, at least in the eyes of the transgenic flies. The level SCA2 expression is too weak in the transgenic SCA2 Drosophila for evaluation. CONCLUSION: SCA3 transgenic Drosophila show ataxic behavior as observed in human patients. Chemical chaperones such as glycerol may prove beneficial in this class of genetic disease, which has no current method of cure.

Spinocerebellar Ataxia Type 3 Confirmed by Genomic Molecular Analysis: A case report

Dominantly inherited spinocerebellar ataxias (SCAs) are a group of the heterogenous neurodegenerative diseases that are characterized by chronic progressive cerebellar ataxia associated with various combinations of other neurological signs. Clinical classification is difficult because of the phenotypic overlap. With the evolution of molecular genetics, the loci and mutations for many of the ataxias have been identified, allowing more definitive molecular classification. We experienced 42 years-old man who presented with progressive both lower leg weakness, dysarthria, ataxia, ophthalmoplegia, and nystagmus. The family history was remarkably suspicious. We could not observe the upper extremity weakness, definite evidences of peripheral neuropathy and myopathy in electrodiagnosis. No abnormal findings in blood chemistry and brain MRI. We performed polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis (PAGE) analysis, found that his gene contained expanded CAG repeats (CAG repeat number was 72). Although no effective treatment exists for most the ataxic syndromes, the accurate diagnosis and the genetic counseling are often important to the patient's family for prognostication.