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1.
Cureus ; 16(7): e65766, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39082045

RESUMO

Oculopharyngeal muscular dystrophy (OPMD) is a late-onset inherited skeletal myopathy. The diagnosis is based on a clinical presentation of blepharoptosis, dysphagia, and a positive family history of the disease in patients past 40 years of age. A 57-year-old male patient presented with ptosis without lid crease, adult-onset dysphagia, and bilateral pseudophakia. The patient underwent ptosis repair of upper eyelids via frontalis slings with silicone rods. His mother was subsequently found to have ptosis, dry eyes, and anorexia due to dysphagia, thus suggesting a probable family history. Based on the comprehensive ophthalmic evaluation, and based on his ptosis, dysphagia, and family history, the patient was diagnosed with OPMD.

2.
Sci Rep ; 14(1): 9811, 2024 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684872

RESUMO

Most research on trinucleotide repeats (TRs) focuses on human diseases, with few on the impact of TR expansions on plant gene expression. This work investigates TRs' effect on global gene expression in Psidium guajava L., a plant species with widespread distribution and significant relevance in the food, pharmacology, and economics sectors. We analyzed TR-containing coding sequences in 1,107 transcripts from 2,256 genes across root, shoot, young leaf, old leaf, and flower bud tissues of the Brazilian guava cultivars Cortibel RM and Paluma. Structural analysis revealed TR sequences with small repeat numbers (5-9) starting with cytosine or guanine or containing these bases. Functional annotation indicated TR-containing genes' involvement in cellular structures and processes (especially cell membranes and signal recognition), stress response, and resistance. Gene expression analysis showed significant variation, with a subset of highly expressed genes in both cultivars. Differential expression highlighted numerous down-regulated genes in Cortibel RM tissues, but not in Paluma, suggesting interplay between tissues and cultivars. Among 72 differentially expressed genes with TRs, 24 form miRNAs, 13 encode transcription factors, and 11 are associated with transposable elements. In addition, a set of 20 SSR-annotated, transcribed, and differentially expressed genes with TRs was selected as phenotypic markers for Psidium guajava and, potentially for closely related species as well.


Assuntos
Regulação da Expressão Gênica de Plantas , Repetições de Microssatélites , Psidium , Psidium/genética , Repetições de Microssatélites/genética , Repetições de Trinucleotídeos/genética , Perfilação da Expressão Gênica , Folhas de Planta/genética , Folhas de Planta/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
Rev. Ciênc. Méd. Biol. (Impr.) ; 21(2): 302-307, out.2022. fig
Artigo em Português | LILACS | ID: biblio-1400465

RESUMO

Introduction: Huntington's disease (HD) is a neurodegenerative disorder caused by CAG expansion repeats in the HTT gene. Usually, the symptoms start to manifest in mid-adulthood. In about 5% of cases, however, the signs begin before the age of 20 years. These cases are known as juvenile HD (JHD). Objective: here we report a case series of JHD from Amazonas, a state where data are scarce due to the restricted access to specialized medical assistance for diagnosis and care. Case series: the patients were attended by neurologists specialized in movement disorders at Manaus. Two cases manifested the disease in childhood (6 and 7 years old) and two cases, in adolescence (12 and 16 years old). All cases showed dystonia and parkinsonism as predominant motor disorders. Moreover, signs of cognitive decline, depression, and psychosis were observed in all patients. Conversely, cerebellar signs, gait disturbances, seizures, and some psychiatric symptoms were variable among the cases. Expansion size varied from 66 to 84 to CAG repeats and the difference in age at onset between parent and child varied from 23 to 43 years. Conclusion: to our knowledge, these are the first clinical reports of JHD in northern Brazil. These cases illustrate the variability in clinical phenotypes and genetic features of JHD cases. Furthermore, they can contribute to the awareness of HD here, both by professionals and the public in general.


Introdução: a doença de Huntington (DH) é um distúrbio neurodegenerativo causado pela expansão de repetições CAG no gene HTT. Geralmente, os sintomas começam a se manifestar na vida adulta tardia. Em cerca de 5% dos casos, no entanto, os sinais começam antes da idade de 20 anos. Esses casos são conhecidos como DH juvenil (DHJ). Objetivo: neste estudo, nós reportamos uma série de casos de DHJ do Amazonas, um estado onde os dados ainda são escassos devido ao acesso restrito à assistência médica especializada para o diagnóstico e cuidado. Série de casos: os pacientes foram atendidos por neurologistas especializados em transtornos do movimento em Manaus. Dois casos manifestaram a doença na infância (6 e 7 anos) e dois casos, na adolescência (12 e 16 anos). Todos os casos apresentaram distonia e parkinsonismo como sintomas motores predominantes. Sinais de declínio cognitivo, depressão e psicose também foram observados em todos os pacientes. Por outro lado, sinais cerebelares, distúrbios da marcha, convulsões e alguns sintomas psiquiátricos foram variáveis entre os casos. O tamanho da expansão CAG variou de 66 a 84 repetições e a diferença na idade de início dos sintomas entre pais e filhos variou de 23 a 43 anos. Conclusão: ao nosso conhecimento, estes são os primeiros relatos clínicos da DHJ na região Norte. Esses casos ilustram a variabilidade nos fenótipos clínicos e nas características genéticas dos casos de DHJ. Além disso, eles podem contribuir para a conscientização da DH na região, tanto pelos profissionais quanto pelo público geral.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Doença de Huntington , Expansão das Repetições de Trinucleotídeos , Antecipação Genética , Transtornos Heredodegenerativos do Sistema Nervoso , Variação Biológica da População
4.
Neurol Sci ; 43(8): 4997-5005, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35469073

RESUMO

OBJECTIVE: The objective of this study is to describe the first series of spinocerebellar ataxia (SCA) in Rio de Janeiro, whose population has a high proportion of mixed Portuguese and African ancestry. METHODS: We reviewed the medical records of patients with progressive ataxia evaluated at the Sarah Network of Rehabilitation Hospitals (Rio de Janeiro). Clinical course, genetic tests for hereditary ataxia, brain MRI, and electroneuromyography were analyzed. RESULTS: SCA was confirmed in 128 individuals, one-third of African descendants. SCA3 predominated (83.6%), followed by SCA7 (7%); SCA2 (3.9%); SCA1, SCA6, and SCA8 (1.6% each); and SCA10 (0.8%). Dysphagia, pyramidal signs, and neurogenic bladder occurred frequently. Oculomotor disorders occurred with SCA3, SCA7, SCA2, and SCA1; peripheral neuropathies with SCA3 and SCA1; extrapyramidal syndromes with SCA3, SCA7, and SCA2; bilateral visual impairment with SCA7; and epilepsy with SCA10. Mobility assistance was required in 75% after 11 years and wheelchair in 25%. The Scale for the Assessment and Rating of Ataxia scores at the last follow-up varied from 2 to 37 (median = 14.50) and correlated positively with duration of the disease. In SCA3, a higher CAG repeats correlated with a lower age at onset. African ethnicity was associated with earlier onset, regardless of CAG repeats. The main brain MRI abnormality was cerebellar atrophy, isolated or associated with brainstem atrophy, "hot cross bun" sign, or brain atrophy. Linear T2 hyperintensity along the medial margin of the globus pallidus occurred in SCA3, SCA2, SCA1, and SCA7. ENMG confirmed peripheral neuropathy in SCA3 and SCA1. CONCLUSION: Machado Joseph disease/SCA3 was the most frequent inherited dominant ataxia in Rio de Janeiro. This study revealed new aspects of ethnic influence in the clinical course and new MRI findings.


Assuntos
Doenças do Sistema Nervoso Periférico , Ataxias Espinocerebelares , Atrofia , Brasil/epidemiologia , Expansão das Repetições de DNA , Humanos , Ataxias Espinocerebelares/complicações , Ataxias Espinocerebelares/diagnóstico por imagem , Ataxias Espinocerebelares/epidemiologia
5.
Electron. j. biotechnol ; Electron. j. biotechnol;50: 37-44, Mar. 2021. graf, tab
Artigo em Inglês | LILACS | ID: biblio-1292321

RESUMO

BACKGROUND: Short Tandem repeats (STRs) existed as popular elements in both eukaryotic and prokaryotic genomes. RESULTS: In this study, we analyzed the characteristics, distributions, and motif features of STRs within whole-genomes of 140 plant species. The results showed that STR density was negatively correlated with the genome size. Hexanucleotide repeat was the most abundant type of STRs. The distribution of algae shows a preference different from that of other plants. By analyzing GC contents of STRs and genome, it was concluded that STR motif was influenced by GC contents. Analysis of the long STRs in genome (length 1000 bp) found that dicots have the more long STRs. For STR types, di- and tri-nucleotide accounted for the highest proportion. Analyzing and designing long STRs in CDS (length 500 bp) was to verify the role of long STRs in Gossypium hirsutum TM-1 and Solanum tuberosum. By comparing the long STRs found in Fragaria x ananassa with other species, some evolutionary characteristics of the long STRs were obtained. CONCLUSIONS: We got the characteristics, distribution, and motif features of STRs in the whole genome of 140 plants and obtained some evolutionary characteristics of long STRs. The study provides useful insights into STR preference, characteristics, and distribution in plants.


Assuntos
Plantas/genética , Variação Genética , Repetições de Microssatélites , Sequência de Bases , Análise de Sequência
6.
Mech Ageing Dev ; 185: 111189, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31759995

RESUMO

INTRODUCTION: Huntington´s disease (HD) is a neurodegenerative disorder characterized by neuropsychiatric, motor and cognitive manifestations. It is caused by expansion of the trinucleotide CAG on HTT. The molecular bases are not completely understood, DNA damage, such as double and single strand breaks and oxidative stress (OS) have been implicated. At telomeres, DNA breaks are less efficiently repaired. Double strand breaks evoke the break induced replication (BIR) mechanism. BIR, plus inefficient repair can produce telomere shortening and cellular senescence. Our aim was to investigate the correlation between leukocyte relative telomeric length (RTL) and HD. METHODS: 206 samples were analyzed, 71 patients with molecular diagnosis and symptomatology (HD), 29 individuals with positive molecular test but asymptomatic (PP) and 106 healthy individuals (NP). RESULTS: We found a significant difference in RTL between HD patients compared with both, PP and NP, independently of subjects' age. DISCUSSION: Here we present evidence supporting an association between telomere shortening and HD. Telomere shortening could be related to DNA damage caused by ROS and defective DNA repair mechanism. Both events have been probed to occur in the presence of a mutant Huntingtin. This study contributes with current evidence suggesting a potential role of telomere shortening as HD biomarker.


Assuntos
Biomarcadores , Proteína Huntingtina/genética , Doença de Huntington , Encurtamento do Telômero , Doenças Assintomáticas , Senescência Celular , Correlação de Dados , Dano ao DNA , Feminino , Humanos , Doença de Huntington/diagnóstico , Doença de Huntington/genética , Doença de Huntington/metabolismo , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Avaliação de Sintomas/métodos , Expansão das Repetições de Trinucleotídeos
8.
Fertil Steril ; 110(3): 476-485.e1, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30098699

RESUMO

OBJECTIVE: To analyze whether telomere length, X-chromosome inactivation (XCI), and androgen receptor (AR) GAG polymorphism are related to idiopathic premature ovarian insufficiency (POI). DESIGN: Case-control study. SETTING: University hospital. PATIENT(S): A total of 121 women, including 46 nonsyndromic POI and 75 controls. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Age, weight, height, body mass index (BMI), systolic and diastolic arterial pressure, E2, androstenedione, T, and C-reactive protein were assessed. Telomere length was estimated by quantitative real-time polymerase chain reaction, XCI was measured using the Human Androgen Receptor and X-linked retinitis pigmentosa 2 (RP2) methylation assays. AR and FMR1 polymorphism was assessed by quantitative fluorescent polymerase chain reaction and sequencing. RESULT(S): Premature ovarian insufficiency women had a higher mean age, weighed less, and exhibited lower C-reactive protein, E2, and androstenedione levels. The AR polymorphism did not differ between the groups. Four patients had premutation (55-200 CGG repeats), and none displayed a full mutation in the FMR1 gene. However, patients with POI showed shorter telomere length and higher frequency of skewed XCI. Extreme skewing (≥90%) was observed in 15% of women with POI, and shorter telomeres correlated with XCI skewing in both groups. CONCLUSION(S): Skewed XCI and shortened telomere length were associated with idiopathic POI, despite no alterations in the AR and FMR1 genes. Additionally, there is a tendency for women with short telomeres to exhibit skewed XCI.


Assuntos
Insuficiência Ovariana Primária/diagnóstico , Insuficiência Ovariana Primária/genética , Encurtamento do Telômero/genética , Telômero/genética , Inativação do Cromossomo X/genética , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Proteína do X Frágil da Deficiência Intelectual/genética , Humanos , Estudos Prospectivos , Receptores Androgênicos/genética , Adulto Jovem
9.
Biosalud ; 15(2): 119-125, jul.-dic. 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-950983

RESUMO

Introducción: La distrofia miotónica es una enfermedad poco frecuente de origen genético. Se produce por aumento de repeticiones de la tripleta CTG en el gen DMPK (locus 19q13.32), o por aumento de repeticiones de CCTG en el gen ZNF9 (locus3q21.3). Su fenotipo es variable y sus principales características son la debilidad muscular progresiva y la miotonía. El objetivo de esta publicación es reportar un caso colombiano de distrofia miotónica tipo 1 con diagnóstico molecular y contribuir a la construcción de datos epidemiológicos locales sobre esta patología. Además, aportar información a médicos generales, pediatras, internistas, fisiatras, neurólogos, y en general al personal de salud que puede tener contacto con pacientes con debilidad muscular progresiva, escenario en el cual la distrofia miotónica es una posibilidad diagnóstica a considerar. Descripción del caso: Hombre de 37 años, con historia de pobre succión neonatal, retraso en los hitos del desarrollo, discapacidad intelectual y, en la adolescencia, aparición de debilidad progresiva generalizada, miotonía y disfagia. El Southernblot y PCR del gen DMPK mostraron un alelo expandido en un rango entre 1100 a 1700 repeticiones del triplete CGT y un alelo normal, confirmando el diagnóstico de distrofia miotónicatipo 1. Conclusión: El paciente aquí reportado presentó fenotipo sugestivo de DM1; el diagnóstico fue confirmado con la prueba molecular. Con el resultado fue posible realizar una consejería genética adecuada y brindar información sobre la enfermedad.


Introduction: Myotonic dystrophy (MD) is a rare genetic disease. It is produced by an increased repetition of the CTG triplet in the DMPK gene (locus 19q13.32), or by increasing repetitions of CCTG in the ZNF9 gene (locus 3q21.3). Its phenotype is variable, and its key features are progressive muscle weakness and myotonia. The aim of this publication is to report a Colombian case of myotonic dystrophy type 1 with molecular diagnosis and to contribute to the construction of local epidemiological data on this pathology. Also, to provide information to general practitioners, pediatricians, internists, physiatrists, neurologists, and health personnel who may have contact with patients with progressive muscle weakness, scenario in which myotonic dystrophy is a diagnostic possibility to be considered. Case description: Thirty-seven year old male with a history of poor neonatal suction, delay in developmental milestones, intellectual disability and, in adolescence, the onset of progressive generalized weakness, myotonia and dysphagia. Southern blot and PCR of DMPK gene showed one expanded allele in a range between 1100-1700 repetitions of the CGT triplet and one normal allele, confirming the diagnosis of myotonic dystrophy type 1. Conclusion: The patient reported here presented a phenotype suggestive of myotonic dystrophy type 1; the diagnosis was confirmed by molecular testing. This result made it possible to offer a proper genetic counseling and provide information about the disease.

10.
Arq. bras. ciênc. saúde ; 34(1): 22-26, jan.-abr. 2009. ilus
Artigo em Português | LILACS | ID: lil-519419

RESUMO

Introdução: A presença de sequências repetidas de DNA já foi identificada como marcadoras de certas doenças neuropsiquiátricas. O gene FMR1 possui sequência rica em repetições CGG, sujeito a expansão quando transmitido por via materna. Alelos pré-mutados (55200 repetições CGG). Na mutação completa, o gene é inativado determinando a síndrome do X frágil (FRAX). Os portadores da pré-mutação não apresentam deficiência cognitiva associada à FRAX, porém, um subgrupo desses indivíduos com mais de 50 anos de idade desenvolve uma síndrome neurológica progressiva, a síndrome de tremor/ataxia associada ao X frágil (Fragile X-associated Tremor/Ataxia Syndrome–FXTAS). Objetivos: Este estudo investigou as características clínicas e moleculares dos familiares de quatro homens com mais de 50 anos de idade, familiares de indivíduos FRAX, uma vez que esses indivíduos possuem risco elevado de desenvolver o quadro de FXTAS. Resultados: Nenhum dos pacientes avaliados possuía FXTAS. Conclusão: A síndrome FXTAS foi recentemente descrita e é pouco conhecida no meio clínico e científico. Dessa forma, a avaliação de familiares de indivíduos FRAX pode contribuir para o melhor entendimento da doença e permitir a determinação de sua incidência na população brasileira.


Introduction: The presence of repeated sequences was already identified as markers of neuropsychiatric diseases. The FMR1 gene shelters a CGGrich sequence which is vulnerable to expansion when transmitted through maternal lineage. Premutated alleles (55 200 CGG repeats). In the full mutation range, the gene is inactivated causing the fragile X syndrome (FRAX). Premutation carriers do not present mental retardation, however a subgroup of permutation carriers older than 50 years can develop a progressive neurological syndrome, the Fragile X-associated Tremor/Ataxia Syndrome (FXTAS). Objectives: This approach had investigated clinical and molecular features offour males - relatives of FRAX individuals – due to the high risk of developing FXTAS. Results: None of the investigated patients had FXTAS. Conclusion: This syndrome was recently described and there is little knowledge about it by clinicians and scientists. Thus, evaluation of people in this condition can contribute to the better understanding of the disease and its incidence in the Brazilian population.


Assuntos
Humanos , Idoso , Cromossomos Humanos X , Proteína do X Frágil da Deficiência Intelectual , Síndrome do Cromossomo X Frágil , Doenças Genéticas Ligadas ao Cromossomo X , Expansão das Repetições de Trinucleotídeos
11.
Gac. méd. Méx ; Gac. méd. Méx;144(5): 413-418, sept.-oct. 2008. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: lil-568030

RESUMO

Antecedentes: La ataxia espinocerebelosa tipo 2 es causada por la expansión del repetido CAG presente en el exón 1 del gen de la ataxina-2, lo cual origina la incorporación de un segmento de poliglutaminas en la proteína mutante. Métodos: Mediante reacción en cadena de la polimerasa y electroforesis capilar se determinó el número de repetidos CAG del gen de la ataxina-2 en 66 individuos pertenecientes a tres familias mexicanas diagnosticadas clínicamente con ataxia espinocerebelosa tipo 2, y en 400 individuos de una muestra de población mestiza mexicana. Resultados: Se identificó la expansión del repetido CAG en 11 sujetos con sintomatología de ataxia espinocerebelosa tipo 2 y en cuatro individuos asintomáticos, lo que confirmó el diagnóstico en dos de las tres familias analizadas. Se determinó que los pacientes con mayor número de repetidos desarrollaron la sintomatología de la enfermedad a una edad más temprana, fenómeno conocido como “anticipación”. Los alelos silvestres presentaron un rango entre 13 y 30 repetidos CAG, siendo el alelo de 22 repetidos el más frecuente, mientras que los alelos mutados mostraron un rango de 36 a 54 repetidos. Conclusiones: La identificación de la expansión del repetido CAG del gen de la ataxina-2 confirmó el diagnóstico clínico de ataxia espinocerebelosa tipo 2.


BACKGROUND: Spinocerebellar ataxia type 2 (SCA2) results from the expansion of a CAG triplet located within the coding sequence of the ataxin-2 gene, which ultimately provokes the incorporation of a stretch of polyglutamines in the mutant protein. METHODS: We determined by PCR and capillary electrophoresis the number of ataxin2 gene CAG repeats in 66 individuals belonging to 3 families, clinically diagnosed with SCA2, and 400 subjects from a sample of the mestizo Mexican population. RESULTS: The CAG repeat expansion was found in 11 symptomatic subjects and four asymptomatic individuals, confirming the SCA2 clinical diagnosis in two out of the three families studied. We noted that patients with longer CAG repeat numbers have an early disease onset, a phenomenon known as anticipation. Wild-type alleles showed a CAG repeat range between 13 and 30, and the allele carrying 22 CAG repeats was the most common among our sample. Mutant alleles also displayed a range between 36 and 54 CAG repeats. CONCLUSIONS: The identification of the CAG repeat expansion facilitates an accurate SCA2 diagnosis.


Assuntos
Humanos , Adolescente , Adulto Jovem , Ataxias Espinocerebelares/genética , Proteínas do Tecido Nervoso/genética , Repetições de Trinucleotídeos , México , Linhagem
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