RESUMO
DYT1 dystonia is an autosomal-dominantly inherited movement disorder, which is usually caused by a GAG deletion in the TOR1A gene. Due to the reduced penetrance of approximately 30-40%, the determination of the mutation in a subject is of limited use with regard to actual manifestation of symptoms. In the present study, we used Affymetrix oligonucleotide microarrays to analyze global gene expression in blood samples of 15 manifesting and 15 non-manifesting mutation carriers in order to identify a susceptibility profile beyond the GAG deletion which is associated with the manifestation of symptoms in DYT1 dystonia. We identified a genetic signature which distinguished between asymptomatic mutation carriers and symptomatic DYT1 patients with 86.7% sensitivity and 100% specificity. This genetic signature could correctly predict the disease state in an independent test set with a sensitivity of 87.5% and a specificity of 85.7%. Conclusively, this genetic signature might provide a possibility to distinguish DYT1 patients from asymptomatic mutation carriers.
Assuntos
Distonia Muscular Deformante/genética , Perfilação da Expressão Gênica , Chaperonas Moleculares/genética , Adulto , Feminino , Predisposição Genética para Doença , Testes Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Penetrância , Repetições de TrinucleotídeosAssuntos
Distonia/epidemiologia , Distonia/genética , Chaperonas Moleculares/genética , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ácido Aspártico/genética , Criança , Predisposição Genética para Doença/epidemiologia , Histidina/genética , Humanos , Pessoa de Meia-IdadeRESUMO
BACKGROUND: The three-nucleotide deletion, triangle upGAG (within the gene TOR1A), is the only proven cause of childhood-onset dystonia (DYT1). A potentially pathogenic role of additional sequence changes within TOR1A has not been conclusively shown. METHODS: DNA sequencing of exon 5 of TOR1A in a patient with DYT1. RESULTS: Detection of sequence change c.863G>A in exon 5 of TOR1A in the patient. The G>A transition results in an exchange of an arginine for glutamine (p.Arg288Gln) in subdomain alpha5 of TOR1A. Several findings point to a potentially pathogenic role of the sequence change in the patient: The base change is absent in 1000 control chromosomes; an Arg at position 288 of TOR1A has been conserved throughout vertebrate evolution, indicating an important role of Arg288 in TOR1A function; functional studies demonstrate enlarged perinuclear space in HEK293 cells overexpressing TOR1A with the p.Arg288Gln mutation. The same morphological changes are observed in cells overexpressing the common triangle upGAG TOR1A mutation but not in cells overexpressing wild-type TOR1A. CONCLUSIONS: The sequence change described here may be a novel pathogenic mutation of TOR1A in DYT1.
Assuntos
Distúrbios Distônicos/diagnóstico , Distúrbios Distônicos/genética , Chaperonas Moleculares/genética , Mutação , Adolescente , Sequência de Aminoácidos , Núcleo Celular/metabolismo , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/genética , Progressão da Doença , Éxons , Feminino , Humanos , Microscopia Eletrônica , Dados de Sequência Molecular , Análise de Sequência de DNA , Homologia de Sequência de AminoácidosRESUMO
Primary torsion dystonia is an autosomal-dominant inherited movement disorder. Most cases are caused by an in-frame deletion (GAG) of the DYT1 gene encoding torsinA. Reduced penetrance and phenotypic variability suggest that alteration of torsinA amino acid sequence is necessary but not sufficient for development of clinical symptoms and that additional factors must contribute to the factual manifestation of the disease. We generated 4 independent transgenic mouse lines, two overexpressing human mutant torsinA and two overexpressing human wildtype torsinA using a strong murine prion protein promoter. Our data provide for the first time in vivo evidence that not only mutant torsinA is detrimental to neuronal cells but that also wildtype torsinA can lead to neuronal dysfunction when overexpressed at high levels. This hypothesis is supported by (i) neuropathological findings, (ii) neurochemistry, (iii) behavioral abnormalities and (iv) DTI-MRI analysis.
Assuntos
Encéfalo/metabolismo , Encéfalo/patologia , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Neurônios/ultraestrutura , Animais , Western Blotting , Química Encefálica , Distonia/genética , Distonia/metabolismo , Distonia/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Transgênicos , Microscopia Eletrônica de Transmissão , Atividade Motora , Neurônios/metabolismo , Neurotransmissores/análise , Fenótipo , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
BACKGROUND: Antiplatelet agents such as acetylsalicylic acid (aspirin) reduce the relative risk for cerebrovascular events in patients with cardiovascular or cerebrovascular disorders by approximately 23 %. Recent observations raise the possibility that aspirin resistance may contribute to the failure of aspirin treatment in a significant proportion of patients (aspirin non-responders). To evaluate the clinical relevance of aspirin non-responder status, we analysed platelet functions in symptomatic and asymptomatic patients treated with aspirin for secondary prevention of cardiovascular and cerebrovascular events. METHODS: A total of 53 patients on 100 mg aspirin daily for secondary prevention (mean treatment duration > 60 months) were included. Patients were categorized as asymptomatic if they were free of cerebrovascular incidents for at least 24 months (n = 18). Symptomatic patients had suffered ischemic strokes or transient ischemic attacks within the previous 3 days (n = 35). Platelet function was assessed using the PFA-100 system that allows for quantitative assessment of platelet function, reporting platelet aggregatability as the time required to close a small aperture in a biologically active membrane. RESULTS: Collagen/epinephrine closure times were significantly shorter in symptomatic patients than in asymptomatic patients (p < 0.01). Individual closing times were normal in 12 of 35 symptomatic patients (34 % non-responders) whereas all asymptomatic patients had prolonged closure times. CONCLUSIONS: Aspirin non-responder status may contribute to failure of aspirin therapy in the secondary prevention of cerebrovascular incidents in as much as 30-40 % of patients. Quantitative assessment of platelet functions may provide a means to predict aspirin treatment failure in individual patients and to re-direct therapeutic strategies.
Assuntos
Aspirina/uso terapêutico , Ataque Isquêmico Transitório/tratamento farmacológico , Ataque Isquêmico Transitório/prevenção & controle , Inibidores da Agregação Plaquetária/uso terapêutico , Agregação Plaquetária/efeitos dos fármacos , Idoso , Aspirina/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Plaquetária , Prevenção SecundáriaRESUMO
A complete documentation of German anatomical science and its representatives during the period of national socialism has not been published as yet--contrary to the situation in other medical disciplines. Instead of German anatomists, American anatomists have occasionally addressed this issue during their meetings and have reported on special aspects, such as the use of Nazi symbols in anatomical textbooks and atlases (Pernkopf 1952) and the use of corpses of justice victims for anatomical research and student education. Also, the genesis of the atrocious collection of "racial" skulls, initiated along with the SS-institution of the "Ahnenerbe" by the anatomist August Hirt of Strasbourg (who ordered more than 90 inmates from concentration camps to be murdered in the gas chamber built in the concentration camp of Natzweiler-Struthof close to Strasbourg, Alsace) has been described by Frederic Kasten and others. A broader view of the patterns of behaviour and political actions and fates of contemporary scientists, ranging from dismissal to clandestine opportunism, affirmative cooperation and fanatic activism can be obtained by the analysis of the activities in research, medical education and academic positions of the following members of the Institute of Anatomy at the Philipp-University in Marburg: Ernst Göppert, Eduard Jacobshagen, Ernst-Theodor Nauck, Adolf Dabelow, Helmut Becher and Alfred Benninghoff, whose activities and fates differ in several respects and allow more general deductions. Also, the individual fates of a number of prosecuted Jewish anatomists (Wassermann, München; Poll, Hamburg), of devoted and active members of the Nazi party (Clara, Leipzig; Blotevogel, Breslau) and of criminal fanatics (Hirt, Strasbourg; Kremer, Münster) are briefly discussed. The present contribution is an attempt to initiate a more detailed study of all German departments of anatomy during the Hitler regime and to generate a public discussion among the younger generation of German anatomists.
Assuntos
Anatomia/história , Socialismo Nacional/história , Alemanha , História do Século XX , Humanos , Judeus/história , Universidades/históriaRESUMO
Usher syndrome is a heterogeneous autosomal recessive trait and the most common cause of hereditary deaf-blindness. Usher syndrome type I (USH1) is characterised by profound congenital sensorineural hearing loss, vestibular dysfunction, and prepubertal onset of retinitis pigmentosa. Of the at least six different loci for USH1, USH1B maps on chromosome 11q13, and the MYO7A gene has been shown to be defective in USH1B. MYO7A encodes myosin VIIA, an unconventional myosin, and it consists of 48 coding exons. In this study, MYO7A was analysed in 34 unrelated Usher type I patients by single-strand conformation polymorphism analysis and direct sequencing. We identified a total of 12 novel and unique mutations, all single base changes. In addition, we found a previously reported nonsense mutation (C31X) on nine alleles of a total of six patients from Denmark.
Assuntos
Heterogeneidade Genética , Perda Auditiva Neurossensorial/genética , Mutação/genética , Miosinas/genética , Retinose Pigmentar/genética , Mapeamento Cromossômico , Dineínas , Feminino , Humanos , Masculino , Miosina VIIa , Polimorfismo Genético , SíndromeRESUMO
A novel rhodopsin missense mutation (M216R) was found in a Danish patient with autosomal dominant retinitis pigmentosa. Clinical examination of the proband disclosed a phenotype of intermediate severity. In view of the predicted amino acid substitution in the 5th transmembrane domain of rhodopsin, the clinical picture of the proband is in keeping with the data from the literature on patients carrying similar mutations.
Assuntos
DNA/análise , Mutação Puntual , Retinose Pigmentar/genética , Rodopsina/genética , Adolescente , Adulto , Dinamarca , Feminino , Seguimentos , Ligação Genética/genética , Humanos , Masculino , Pessoa de Meia-Idade , Ácidos Nucleicos Heteroduplexes/análise , Linhagem , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Retinose Pigmentar/patologia , Retinose Pigmentar/fisiopatologia , Acuidade VisualRESUMO
Hippocampal brain slices show CA1 injury similar to that seen after global ischemia in vivo. Cooling rats to 31 degrees C prior to sacrifice or cooling slices to 21 degrees C for 45 min increased the percentage of normal CA1 pyramidal cells after 5 h in vitro from 30% to over 80%. Brain slices also show a unique, consistent injury in dentate which is lessened by transient cooling to 21 degrees C but not by cooling the animal.
Assuntos
Criopreservação/métodos , Hipocampo/patologia , Hipotermia Induzida , Análise de Variância , Animais , Técnicas In Vitro , Masculino , Ratos , Ratos EndogâmicosRESUMO
Growth and dedifferentiation of a heterogeneous mouse chondrocyte population, prepared from epiphyses of mouse embryos (day 17 of gestation), were studied in primary monolayer culture. At different times of culture, light and electron microscopic investigations were carried out and the change of collagen types was shown by immunofluorescence microscopy. During the first four days in culture, chondrocytes express their typical phenotype. Round or polygonal cells are embedded in a metachromatically staining matrix and produce type II collagen. After four to eight days in vitro most of the chondrocytes lose their matrix capsule and alter to fibroblast-like cells. Simultaneously, a switch of collagen synthesis to type III and type I collagen occurs, whereas the type II collagen synthesis is stopped. Altered cells and transitional stages have intracellular glycogen like typical chondrocytes, but show phagocytosis and indications of cell migration like fibroblasts. It is proposed that these cells, originating from a subpopulation of epiphyseal cartilage, are able to differentiate and dedifferentiate in vitro.