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1.
Mol Psychiatry ; 21(8): 1112-24, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26481318

RESUMO

Pathological expansion of a G4C2 repeat, located in the 5' regulatory region of C9orf72, is the most common genetic cause of frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). C9orf72 patients have highly variable onset ages suggesting the presence of modifying factors and/or anticipation. We studied 72 Belgian index patients with FTLD, FTLD-ALS or ALS and 61 relatives with a C9orf72 repeat expansion. We assessed the effect of G4C2 expansion size on onset age, the role of anticipation and the effect of repeat size on methylation and C9orf72 promoter activity. G4C2 expansion sizes varied in blood between 45 and over 2100 repeat units with short expansions (45-78 units) present in 5.6% of 72 index patients with an expansion. Short expansions co-segregated with disease in two families. The subject with a short expansion in blood but an indication of mosaicism in brain showed the same pathology as those with a long expansion. Further, we provided evidence for an association of G4C2 expansion size with onset age (P<0.05) most likely explained by an association of methylation state of the 5' flanking CpG island and expansion size in blood (P<0.0001) and brain (P<0.05). In several informative C9orf72 parent-child transmissions, we identified earlier onset ages, increasing expansion sizes and/or increasing methylation states (P=0.0034) of the 5' CpG island, reminiscent of disease anticipation. Also, intermediate repeats (7-24 units) showed a slightly higher methylation degree (P<0.0001) and a decrease of C9orf72 promoter activity (P<0.0001) compared with normal short repeats (2-6 units). Decrease of transcriptional activity was even more prominent in the presence of small deletions flanking G4C2 (P<0.0001). Here we showed that increased methylation of CpGs in the C9orf72 promoter may explain how an increasing G4C2 size lead to loss-of-function without excluding repeat length-dependent toxic gain-of-function. These data provide insights into disease mechanisms and have important implications for diagnostic counseling and potential therapeutic approaches.


Assuntos
Esclerose Lateral Amiotrófica/genética , Proteínas/genética , Adulto , Idade de Início , Esclerose Lateral Amiotrófica/metabolismo , Bélgica , Proteína C9orf72 , Ilhas de CpG/genética , Metilação de DNA/genética , Regulação para Baixo , Epigênese Genética/genética , Epigenômica/métodos , Feminino , Degeneração Lobar Frontotemporal/genética , Degeneração Lobar Frontotemporal/metabolismo , Predisposição Genética para Doença/genética , Humanos , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética , Proteínas/metabolismo
2.
J Neurol Neurosurg Psychiatry ; 81(1): 90-3, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20019223

RESUMO

BACKGROUND: m.14487T>C, a missense mutation (p.M63V) affecting the ND6 subunit of complex I of the mitochondrial respiratory chain, has been reported in isolated childhood cases with Leigh syndrome (LS) and progressive dystonia. Adult-onset phenotypes have not been reported. OBJECTIVES: To determine the clinical-neurological spectrum and associated mutation loads in an extended m.14487T>C family. METHODS: A genotype-phenotype correlation study of a Belgian five-generation family with 12 affected family members segregating m.14487T>C was carried out. Clinical and mutation load data were available for nine family members. Biochemical analysis of the respiratory chain was performed in three muscle biopsies. RESULTS: Heteroplasmic m.14487T>C levels (36-52% in leucocytes, 97-99% in muscle) were found in patients with progressive myoclonic epilepsy (PME) and dystonia or progressive hypokinetic-rigid syndrome. Patients with infantile LS were homoplasmic (99-100% in leucocytes, 100% in muscle). We found lower mutation loads (between 8 and 35% in blood) in adult patients with clinical features including migraine with aura, Leber hereditary optic neuropathy, sensorineural hearing loss and diabetes mellitus type 2. Despite homoplasmic mutation loads, complex I catalytic activity was only moderately decreased in muscle tissue. INTERPRETATION: m.14487T>C resulted in a broad spectrum of phenotypes in our family. Depending on the mutation load, it caused severe encephalopathies ranging from infantile LS to adult-onset PME with dystonia. This is the first report of PME as an important neurological manifestation of an isolated mitochondrial complex I defect.


Assuntos
Doença de Leigh/genética , Epilepsias Mioclônicas Progressivas/genética , NADH Desidrogenase/genética , Adulto , Idade de Início , Bélgica , Criança , DNA Mitocondrial/genética , Distúrbios Distônicos/genética , Família , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Mutação de Sentido Incorreto/genética , Linhagem , Fenótipo , Adulto Jovem
3.
Brain ; 132(Pt 10): 2688-98, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19696032

RESUMO

Ataxia with oculomotor apraxia type 2 (AOA2) is an autosomal recessive disease due to mutations in the senataxin gene, causing progressive cerebellar ataxia with peripheral neuropathy, cerebellar atrophy, occasional oculomotor apraxia and elevated alpha-feto-protein (AFP) serum level. We compiled a series of 67 previously reported and 58 novel ataxic patients who underwent senataxin gene sequencing because of suspected AOA2. An AOA2 diagnosis was established for 90 patients, originating from 15 countries worldwide, and 25 new senataxin gene mutations were found. In patients with AOA2, median AFP serum level was 31.0 microg/l at diagnosis, which was higher than the median AFP level of AOA2 negative patients: 13.8 microg/l, P = 0.0004; itself higher than the normal level (3.4 microg/l, range from 0.5 to 17.2 microg/l) because elevated AFP was one of the possible selection criteria. Polyneuropathy was found in 97.5% of AOA2 patients, cerebellar atrophy in 96%, occasional oculomotor apraxia in 51%, pyramidal signs in 20.5%, head tremor in 14%, dystonia in 13.5%, strabismus in 12.3% and chorea in 9.5%. No patient was lacking both peripheral neuropathy and cerebellar atrophy. The age at onset and presence of occasional oculomotor apraxia were negatively correlated to the progression rate of the disease (P = 0.03 and P = 0.009, respectively), whereas strabismus was positively correlated to the progression rate (P = 0.03). An increased AFP level as well as cerebellar atrophy seem to be stable in the course of the disease and to occur mostly at or before the onset of the disease. One of the two patients with a normal AFP level at diagnosis had high AFP levels 4 years later, while the other had borderline levels. The probability of missing AOA2 diagnosis, in case of sequencing senataxin gene only in non-Friedreich ataxia non-ataxia-telangiectasia ataxic patients with AFP level > or =7 microg/l, is 0.23% and the probability for a non-Friedreich ataxia non-ataxia-telangiectasia ataxic patient to be affected with AOA2 with AFP levels > or =7 microg/l is 46%. Therefore, selection of patients with an AFP level above 7 microg/l for senataxin gene sequencing is a good strategy for AOA2 diagnosis. Pyramidal signs and dystonia were more frequent and disease was less severe with missense mutations in the helicase domain of senataxin gene than with missense mutations out of helicase domain and deletion and nonsense mutations (P = 0.001, P = 0.008 and P = 0.01, respectively). The lack of pyramidal signs in most patients may be explained by masking due to severe motor neuropathy.


Assuntos
Apraxia Ideomotora/fisiopatologia , Ataxia/complicações , Ataxia/patologia , Oftalmoplegia/fisiopatologia , Adulto , Idade de Início , Apraxia Ideomotora/genética , Ataxia/genética , Estudos de Coortes , DNA Helicases , Progressão da Doença , Feminino , Genótipo , Humanos , Imageamento por Ressonância Magnética , Masculino , Enzimas Multifuncionais , Mutação de Sentido Incorreto/genética , Oftalmoplegia/genética , Fenótipo , RNA Helicases/genética , RNA Helicases/metabolismo , Estudos Retrospectivos , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/metabolismo
4.
Clin Neurol Neurosurg ; 194: 105849, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32388246

RESUMO

OBJECTIVES: Anti-Hu antibodies (Hu-Abs) are the most frequent onconeural antibodies associated with paraneoplastic neurologic syndromes (PNS). PNS include a variety of neurological syndromes, affecting less than 1/10,000 patients with cancer. In the majority of cases, PNS will manifest before the malignancy is diagnosed. We found a case in which PNS was diagnosed without finding a primary malignancy after extensive work-up and even post-mortem autopsy. PATIENT AND METHODS: We present a case report of a 58-year-old man. This article includes extensive clinical work-up, full-body autopsy and brain autopsy with classical histochemical and myelin stainings and immunohistochemistry was performed. RESULTS: The patient developed a progressive trigeminal neuropathy over a period of 5 years, in combination with cerebellar degeneration, asymmetrical brainstem and limbic encephalitis. Serum showed repeatedly high anti-Hu antibodies. Comprehensive cancer screening could not demonstrate any primary malignancy. Therapy with corticosteroids, plasma exchange, cyclophosphamide and rituximab showed no beneficial effect. He died from the complications of enteric ganglionitis 5 years after onset of the first symptoms. A postmortem autopsy could not detect a primary malignancy either. Brain morphology is described in detail. CONCLUSION: Paraneoplastic anti-Hu encephalitis cases associated with SCLC or other primary neoplasms are well known. An adult with a progressive multifocal neurological syndrome in the presence of positive anti-Hu antibodies, but without any primary neoplasm after a follow-up over 5 years is unusual.


Assuntos
Dor Abdominal/etiologia , Doenças Autoimunes/complicações , Encefalite Límbica/etiologia , Doenças do Nervo Trigêmeo/etiologia , Anticorpos Antinucleares , Autopsia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Evolução Fatal , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Síndromes Paraneoplásicas do Sistema Nervoso/diagnóstico , Tomografia por Emissão de Pósitrons
5.
Orphanet J Rare Dis ; 15(1): 83, 2020 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-32248831

RESUMO

BACKGROUND: Late-onset Pompe disease (LOPD) is a rare, hereditary, progressive disorder that is usually characterized by limb-girdle muscle weakness and/or respiratory insufficiency. LOPD is caused by mutations in the acid alpha-glucosidase (GAA) gene and treated with enzyme replacement therapy (ERT). METHODS: We studied the clinical, brain imaging, and genetic features of the Belgian cohort of late-onset Pompe disease patients (N = 52), and explored the sensitivity of different outcome measures, during a longitudinal period of 7 years (2010-2017), including the activity limitations ActivLim score, 6 min walking distance (6MWD), 10 m walk test (10MWT), MRC sum score, and forced vital capacity (FVC) sitting/supine. RESULTS: In Belgium, we calculated an LOPD prevalence of 3.9 per million. Mean age at onset of 52 LOPD patients was 28.9 years (SD: 15.8 y), ranging from 7 months to 68 years. Seventy-five percent (N = 39) of the patients initially presented with limb-girdle weakness, whereas in 13% (N = 7) respiratory symptoms were the only initial symptom. Non-invasive ventilation (NIV) was started in 37% (N = 19), at a mean age of 49.5 years (SD: 11.9 y), with a mean duration of 15 years (SD: 10.2 y) after symptom onset. Brain imaging revealed abnormalities in 25% (N = 8) of the patients, with the presence of small cerebral aneurysm(s) in two patients and a vertebrobasilar dolichoectasia in another two. Mean diagnostic delay was 12.9 years. All patients were compound heterozygotes with the most prevalent mutation being c.-32-13 T > G in 96%. We identified two novel mutations in GAA: c.1610_1611delA and c.186dup11. For the 6MWD, MRC sum score, FVC sitting and FVC supine, we measured a significant decrease over time (p = 0.0002, p = 0.0001, p = 0.0077, p = 0.0151), which was not revealed with the ActivLim score and 10MWT (p > 0.05). CONCLUSIONS: Awareness on LOPD should even be further increased because of the long diagnostic delay. The 6MWD, but not the ActivLim score, is a sensitive outcome measure to follow up LOPD patients.


Assuntos
Doença de Depósito de Glicogênio Tipo II , Bélgica/epidemiologia , Diagnóstico Tardio , Terapia de Reposição de Enzimas , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Doença de Depósito de Glicogênio Tipo II/epidemiologia , Doença de Depósito de Glicogênio Tipo II/genética , Humanos , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , alfa-Glucosidases/uso terapêutico
7.
Eur Neurol ; 59(3-4): 159-63, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18230873

RESUMO

BACKGROUND/AIMS: To determine the efficacy of infliximab combined with weekly methotrexate in drug-naive recent-onset dermatomyositis and polymyositis. METHODS: A multicentre open-label controlled trial was conducted. Disease activity was assessed using patient's and physician's disease activity assessment, manual muscle testing (MMT), handheld dynamometry, and serum CK. The primary objective was to assess the efficacy using MMT after a period of 26 weeks. RESULTS: The study was terminated prematurely because of a low inclusion rate and a high drop-out rate due to disease progression and the occurrence of an infusion reaction. The few patients who did reach the primary endpoint showed improvement in all aspects studied. CONCLUSION: Infliximab combined with weekly methotrexate might be safe and well tolerated in a small subgroup of patients with drug-naive recent-onset myositis. At present, we do not advocate the use of this treatment because treatment response cannot be predicted beforehand.


Assuntos
Anticorpos/uso terapêutico , Antirreumáticos/uso terapêutico , Dermatomiosite/tratamento farmacológico , Metotrexato/uso terapêutico , Polimiosite/tratamento farmacológico , Fator de Necrose Tumoral alfa/imunologia , Adolescente , Adulto , Idoso , Proteína C-Reativa/metabolismo , Quimioterapia Combinada , Estudos de Avaliação como Assunto , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
8.
Eur J Neurol ; 14(2): 224-7, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17250734

RESUMO

A 49-year-old man presented with episodic hypothermia many years after sustaining a contusional brain injury. Brain magnetic resonance imaging demonstrated the destruction of the anterior parts of the corpus callosum without hypothalamic lesions. Nevertheless, delayed hypothalamic dysfunction at the neurotransmitter level is the probable pathophysiological key factor. Clomipramine treatment was beneficial. This case expands the spectrum of Shapiro's syndrome.


Assuntos
Lesões Encefálicas/complicações , Hipotermia/etiologia , Temperatura Corporal/efeitos dos fármacos , Lesões Encefálicas/diagnóstico , Clomipramina/uso terapêutico , Corpo Caloso/patologia , Humanos , Hipotermia/tratamento farmacológico , Hipotermia/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Síndrome
9.
Acta Clin Belg ; 70(1): 61-4, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25268468

RESUMO

We report a 49-year-old patient with necrotizing myopathy and a right renal mass. After laparoscopic radical nephrectomy, a remission of myopathy was seen. Pathologic evaluation of the nephrectomy specimen revealed a clear cell renal cell carcinoma. Relapse of myopathy 6 months postoperatively coincided with the diagnosis of the appearance of liver metastatic disease. After initiation of treatment with an mTOR-inhibitor, myopathy became less active requiring smaller amounts of corticosteroids with a complete remission of myopathy after 3 months of systemic treatment for metastatic renal cell cancer.


Assuntos
Carcinoma de Células Renais/complicações , Neoplasias Renais/complicações , Doenças Musculares/etiologia , Síndromes Paraneoplásicas/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Músculos/patologia , Doenças Musculares/patologia , Necrose
10.
J Neuropathol Exp Neurol ; 53(4): 369-76, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8021710

RESUMO

Cell adhesion molecules participate in target-effector cell interactions in cell-mediated cytotoxicity and in leukodiapedesis in inflammatory diseases. Two ligand-receptor pairs may play a role in the adhesion of cytotoxic T cells to their targets: 1) intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1), and 2) LFA-3 and CD2. We therefore immunolocalized these molecules in myopathies where there is evidence for T cell-mediated myocytotoxicity, namely inclusion body myositis, polymyositis, and Duchenne dystrophy. Autoaggressive inflammatory cells close to invaded muscle fibers showed an increased expression of ICAM-1 and LFA-1. The nonnecrotic muscle fibers invaded by autoaggressive cells expressed ICAM-1 where their surfaces faced the invading cells. That immunoreactivity for ICAM-1 on the invading cells was distinct from that on the opposite muscle fiber surface was established by colocalization of ICAM-1 with the sarcolemmal marker dystrophin (or beta-spectrin) and was also confirmed by confocal microscopy. Leukodiapedesis in inflamed tissues is mediated by ICAM-1, LFA-3, vascular cell adhesion molecule-1 (VCAM-1), and E-selectin associated with endothelial cells. In dermatomyositis ICAM-1 was strongly expressed on endothelial cells of perimysial arterioles and venules and on some perifascicular capillaries. In all the other myopathies ICAM-1 and LFA-3 expressions were increased on endothelia of capillaries surrounded by inflammatory cells. VCAM-1 was detected in few arterioles in all diseases. E-selectin was not detected at any site in any disorder.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Moléculas de Adesão Celular/análise , Distrofias Musculares/imunologia , Miosite/imunologia , Dermatomiosite/imunologia , Expressão Gênica , Humanos , Imuno-Histoquímica , Polimiosite/imunologia
11.
J Neuropathol Exp Neurol ; 55(5): 563-77, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8627347

RESUMO

The two major types of lesions in myofibrillar myopathy consist of hyaline spheroidal structures composed of compacted myofibrillar residues, and nonhyaline lesions that comprise foci of myofibrillar destruction. We employed immunocytochemical analysis to further characterize these abnormalities. The nonhyaline lesions are depleted of actin, alpha-actinin, myosin, and, less consistently, of titin and nebulin. Thus, each major component of the myofibrils is lost or decreased. These lesions also react strongly for both NCAM and desmin. By contrast, the hyaline structures are highly enriched in actin, are immunoreactive for fast and slow myosin, and show increased expression of titin, nebulin, and alpha-actinin. They fail to react for NCAM and react variably for desmin. Both types of lesion react, but with differing intensities, for gelsolin, dystrophin, beta-amyloid precursor protein (beta APP) epitopes amino-terminal to the alpha-secretase site, alpha 1-antichymotrypsin, and ubiquitin, and both can be congophilic. The increased expressions of desmin, dystrophin and gelsolin in muscle are also confirmed by immunoblot studies. The results, in harmony with the ultrastructural findings described in the companion paper, suggest that myofibrillar myopathy is conditioned by abnormal activation of a degradative process that primarily affects the myofibrils. A structural abnormality of desmin alone may not be sufficient to disrupt the myofibrillar architecture, but abnormal activation of a phosphorylating process could account for dissolution of the myofibrils. The cause and significance of the ectopic overexpression of desmin, dystrophin, NCAM, and beta APP components, and the chemical basis of the congophilia remain unknown.


Assuntos
Desmina/análise , Corpos de Inclusão/química , Proteínas Musculares/análise , Miofibrilas/química , Miosite/patologia , Doenças Neuromusculares/patologia , Actinas/análise , Adulto , Idoso , Amiloide/análise , Precursor de Proteína beta-Amiloide/análise , Diferenciação Celular , Vermelho Congo , Proteínas do Citoesqueleto/análise , Distrofina/análise , Feminino , Gelsolina/análise , Humanos , Hialina/química , Técnicas Imunoenzimáticas , Corpos de Inclusão/ultraestrutura , Masculino , Microscopia de Fluorescência , Pessoa de Meia-Idade , Miofibrilas/ultraestrutura , Miosite/metabolismo , Doenças Neuromusculares/metabolismo , Regeneração , Ubiquitinas/análise
12.
Neuromuscul Disord ; 6(4): 255-60, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8887954

RESUMO

Non-granulomatous nodular accumulations of inflammatory cells in inflammatory myopathies were studied to characterize adhesion mechanisms used for leukocyte recruitment. The nodules had a B-cell-rich center surrounded by a helper T-cell-rich peripheral zone, resembling lymph nodes. The T-cell-rich zones harbored high-walled venules resembling high endothelial venules (HEV), whose endothelia frequently expressed ICAM-1, VCAM-1, and less constantly E-selectin. This endothelial adhesion molecule profile differs from that found in polymyositis, inclusion body myositis, or dermatomyositis, but resembles that in lymphoid tissues. Also, the peripheral lymph node addressin, a vascular addressin specific for peripheral lymphoid tissue HEV, was present on many HEV. This adhesion system is probably responsible for the excessive lymphocyte recruitment. The similar cellular organization and lymphocyte recirculation mechanisms of the nodular infiltrates in muscle and of lymph nodes suggest that the former may also produce antibodies.


Assuntos
Moléculas de Adesão Celular/análise , Lectinas , Linfonodos/química , Miosite/imunologia , Miosite/patologia , Tonsila Palatina/química , Adulto , Idoso , Anticorpos Monoclonais , Antígenos CD/análise , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos B/análise , Antígenos de Diferenciação de Linfócitos B/imunologia , Antígenos de Superfície/análise , Antígenos de Superfície/imunologia , Apêndice/química , Apêndice/patologia , Complexo CD3/análise , Linfócitos T CD4-Positivos/química , Antígeno CD56/análise , Antígeno CD56/imunologia , Linfócitos T CD8-Positivos/química , Selectina E/análise , Selectina E/imunologia , Feminino , Imunofluorescência , Humanos , Molécula 1 de Adesão Intercelular/análise , Molécula 1 de Adesão Intercelular/imunologia , Linfonodos/patologia , Macrófagos/química , Masculino , Proteínas de Membrana , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Tonsila Palatina/patologia , Receptores de Retorno de Linfócitos/análise , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico , Molécula 1 de Adesão de Célula Vascular/análise , Molécula 1 de Adesão de Célula Vascular/imunologia
13.
Neuromuscul Disord ; 6(5): 339-49, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8938698

RESUMO

Streaming of Z-disks and focal myofibrillar degeneration occur in target formations (TF) and unstructured cores (UC). Similar myofibrillar alterations are also part of the spectrum of ultrastructural reactions that can occur in the myopathies associated with myofibrillar degeneration and abnormal foci of desmin positivity. In the latter disorders, there is ectopic overexpression of dystrophin, neural cell adhesion molecule (NCAM), gelsolin, beta-amyloid precursor protein (beta APP) epitopes, alpha 1-antichymotrypsin (alpha 1-ACT), and many abnormal fiber regions are also strongly congophilic. Therefore, we searched for similar abnormalities in TF and UC. The UC and the center of TF show increased immunoreactivity for actin, alpha-actinin, gelsolin, dystrophin, beta APP epitopes, alpha 1-ACT, beta 2-microglobulin, desmin, and NCAM, but minimal or no congophilia. The periphery of the TF reacts strongly for nebulin but not for actin. The observed immunocytochemical alterations in TF and UC may represent a stereotyped cellular response associated with myofibrillar degeneration due to any cause. However, the three-dimensional profile of the TF and UC as well as their fiber-type specificity distinguish them from lesions that have similar immunocytochemical profiles in other myopathies.


Assuntos
Peptídeos beta-Amiloides/biossíntese , Desmina/biossíntese , Distrofina/biossíntese , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Peptídeos beta-Amiloides/análise , Peptídeos beta-Amiloides/imunologia , Especificidade de Anticorpos , Atrofia , Citoesqueleto/química , Citoesqueleto/metabolismo , Desmina/análise , Desmina/imunologia , Distrofina/análise , Distrofina/imunologia , Epitopos/análise , Humanos , Imuno-Histoquímica , Denervação Muscular , Músculo Esquelético/inervação , Miofibrilas/química , Miofibrilas/metabolismo
14.
Neuromuscul Disord ; 9(4): 239-46, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10399751

RESUMO

Adhesion molecule upregulation occurs in inflammatory myopathies, and is one of the myriad functions of tumor necrosis factor-alpha (TNF-alpha). TNF-alpha acts via two different receptors of 55 (TNF-R55) and 75 kD (TNF-R75). We immunolocalized TNF-alpha and its receptors in polymyositis, inclusion body myositis and dermatomyositis. In each myopathy, TNF-alpha was detected in macrophages, in myonuclei in regenerating muscle fibers, and freely dispersed in endomysial or perimysial connective tissue. Many endothelial cells in dermatomyositis expressed TNF-alpha. TNF-R55 was strongly expressed on myonuclei of regenerating muscle fibers. TNF-R75 was increased on endothelial cells in the midst of inflammatory infiltrates in each myopathy, and on perifascicular and perimysial endothelia, remote from inflammatory foci in dermatomyositis. Possible TNF-alpha-mediated effects include: increased transendothelial cell trafficking, activation of T/B cells and macrophages, induction of MHC-I gene products, and focal muscle fiber atrophy. In dermatomyositis, the upregulated TNF-R75, via its consensus elements for transcription factors, may be involved in endothelial cell degeneration. Strong TNF-R55 expression on regenerating myonuclei is consistent with a role of TNF-alpha and TNF-R55 in muscle regeneration.


Assuntos
Miosite/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Antígenos CD/biossíntese , Antígenos CD/genética , Dermatomiosite/metabolismo , Dermatomiosite/patologia , Endotélio Vascular/citologia , Endotélio Vascular/patologia , Humanos , Imuno-Histoquímica , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Miosite/patologia , Miosite de Corpos de Inclusão/metabolismo , Miosite de Corpos de Inclusão/patologia , Polimiosite/metabolismo , Polimiosite/patologia , Receptores do Fator de Necrose Tumoral/biossíntese , Receptores do Fator de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral , Regulação para Cima/fisiologia
15.
J Neurol Sci ; 181(1-2): 13-8, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11099706

RESUMO

The pathogenesis of late-onset epileptic seizures after thrombo-embolic cerebral infarction is poorly understood. Our previous positron emission tomographic (PET) studies with 15O have demonstrated that post-apoplectic epilepsy is associated with more severe brain ischemia, but we were unable to determine if this was the cause or the consequence of the seizures. Using cobalt-55 (55Co) as PET tracer we can now distinguish recurrent, recent infarction in patients with a previous old infarct in the same vascular territory. In seven out of twelve patients with post-apoplectic seizures an increased uptake of 55Co was observed in the border area and in two of them also within the old infarct core. In the control group, composed of eight seizure-free patients with also an old infarct involving the cortical territory of the middle cerebral artery, no increase in 55Co uptake was observed on PET examination. The present study indicates that in a significant number of patients late-onset epilepsy is the clinical expression of recurrent strokes, occurring in the same vascular territory.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Epilepsia/diagnóstico por imagem , Epilepsia/etiologia , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Idoso , Córtex Cerebral/patologia , Radioisótopos de Cobalto , Eletroencefalografia , Epilepsia/patologia , Feminino , Humanos , Infarto da Artéria Cerebral Média/patologia , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Tomografia Computadorizada de Emissão
16.
Neurotoxicology ; 15(2): 331-40, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7991222

RESUMO

Organophosphate (OP) poisoning produces various forms of acute, subacute, or delayed neurotoxicity. We investigated in vivo the relationship between clinical, histochemical and electromyographic (EMG) parameters in rats at various stages of poisoning by paraoxon or fenthion. Paraoxon is acutely toxic, whereas fenthion produces more sustained AChE inhibition. Fenthion has been involved in a subacute type of OP-related neurotoxicity in patients, the so-called intermediate syndrome. The animals underwent serial EMGs, with single and repetitive nerve stimulation, and concomitant contralateral muscle biopsies to determine the end-plate acetylcholinesterase (AChE) activity. Repetitive activity (RA) after single nerve stimulation and decrements on repetitive nerve stimulation (RNS) were the major EMG findings in either type of poisoning, occurring in the initial and later stages of the poisoning, respectively. RA was highly correlated to fasciculations in acute, but not in prolonged intoxication. Amplitude decrements provoked by RNS occurred only in weak rats with severe end-plate AChE inhibition. The smallest amplitude occurred either at the second response with gradual improvement in the subsequent responses (decrement-increment phenomenon), or the amplitude decrease progressed up to the last response (decrement phenomenon). The decrement-increment phenomenon preceded the decrement phenomenon and occurred at a slightly less severe degree of AChE inhibition. Various types of impairment of neuromuscular transmission coexist, probably to a different extent at distinct stages of anticholinesterase poisoning.


Assuntos
Inibidores da Colinesterase/intoxicação , Eletromiografia , Fention/intoxicação , Placa Motora/efeitos dos fármacos , Paraoxon/intoxicação , Animais , Estimulação Elétrica , Masculino , Placa Motora/enzimologia , Ratos , Ratos Wistar
17.
Neurotoxicology ; 19(6): 833-8, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9863772

RESUMO

Acute organophosphorus anticholinesterase poisoning induces a necrotizing end-plate myopathy in rats and patients. Acetylcholine (ACh) excess leads to prolonged synaptic currents and increased influx of cations including calcium through the postsynaptic ACh receptor channels with prolonged muscle membrane depolarization, excess calcium influx into the sarcoplasm, and ultimately muscle fiber necrosis. Quinoline derivatives such as quinidine induce or worsen pre- and postsynaptic disorders of neuromuscular transmission in humans, and are beneficial in patients suffering from a rare congenital myasthenic syndrome called the slow channel congenital myasthenic syndrome. These drugs correct the prolonged opening times of the mutated acetylcholine receptor channels in this myasthenic syndrome. We treated paraoxon-poisoned rats with 4 x 10 or 4 x 50 mg/kg of quinidine and assessed the severity of the necrotizing myopathy in gastrocnemius and diaphragm muscle biopsies. Fasciculations were decreased and the necrotizing myopathy was prevented in most treated rats, with absence of necrotic muscle fibers in most animals in the high-dose group. Survival was not different from untreated poisoned animals. A number of physiological mechanisms, including blocking of presynaptic voltage-gated sodium or calcium channels or inhibition of the postsynaptic ACh receptors channels may have contributed to the attenuation of the myonecrosis. The optimal dose and the drug of choice amongst the clinically available quinoline derivatives remains to be determined.


Assuntos
Inibidores da Colinesterase/intoxicação , Inseticidas/intoxicação , Doenças Musculares/prevenção & controle , Paraoxon/intoxicação , Quinidina/uso terapêutico , Animais , Biópsia , Inseticidas/antagonistas & inibidores , Masculino , Fibras Musculares Esqueléticas/patologia , Doenças Musculares/induzido quimicamente , Doenças Musculares/patologia , Necrose , Paraoxon/antagonistas & inibidores , Ratos , Ratos Wistar
18.
Neurotoxicology ; 15(2): 341-8, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7991223

RESUMO

The intermediate syndrome in organophosphate poisoning is clinically characterized by weakness in the territory of cranial nerves, weakness of respiratory, neck and proximal limb muscles, and depressed deep tendon reflexes. It occurs between the acute cholinergic crisis and the usual onset of organophosphate-induced delayed neurotoxicity. The weakness has been ascribed to muscle fiber necrosis. Fenthion has been the most common cause. This study assesses the occurrence of the necrotizing myopathy in rats in relation to the clinical course and the acetylcholinesterase (AChE) inhibition after poisoning with organophosphates representative for each of the major types of organophosphate-related neurotoxicity. Marked differences are noted in the duration of cholinergic symptoms and of AChE inhibition after either paraoxon and mipafox, or fenthion poisoning. The necrotizing myopathy begins shortly after the initial decline in AChE activity with all organophosphates studied. Maximal muscle involvement occurs within the first 2 days of the poisoning with all organophosphates studied. The myopathy is not aggravated by a further decline in AChE activity in fenthion poisoning. Our data argues against the monophasic necrotizing myopathy being the cause of the intermediate syndrome, and is suggestive of persistent AChE inhibition being involved.


Assuntos
Inibidores da Colinesterase/intoxicação , Inseticidas/intoxicação , Fibras Musculares Esqueléticas/efeitos dos fármacos , Animais , Fention/intoxicação , Isoflurofato/análogos & derivados , Isoflurofato/intoxicação , Fibras Musculares Esqueléticas/patologia , Necrose , Paraoxon/intoxicação , Ratos , Ratos Wistar , Fatores de Tempo
19.
Clin Neuropathol ; 23(2): 76-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15074581

RESUMO

Necrotizing myopathy without prominent inflammatory changes is increasingly being recognized as a form of inflammatory myopathy, different from dermatomyositis, polymyositis and sporadic inclusion-body myositis. We report a patient with a chronic steroid-responsive myopathy and an ill-defined overlap syndrome. The muscle biopsy showed thickened capillaries and arterioles and deposition of the membrane attack complex in the replicated mural elements of some vessels. The surface of all muscle fibers showed major histocompatibility class I immunoreactivity. Similar patients have rarely been reported, either suffering from an undifferentiated connective tissue disorder or a carcinoma. The link between the muscle fiber necrosis and the microangiopathy is unclear. Absence of prominent inflammatory changes in a diagnostic muscle biopsy does not exclude the diagnosis of a treatable autoimmune inflammatory myopathy.


Assuntos
Complexo de Ataque à Membrana do Sistema Complemento/imunologia , Músculo Esquelético/imunologia , Músculo Esquelético/patologia , Doenças Musculares/imunologia , Doenças Musculares/patologia , Adulto , Biópsia , Humanos , Masculino , Microcirculação/imunologia , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/irrigação sanguínea , Necrose
20.
Clin Neuropathol ; 9(6): 299-304, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2286022

RESUMO

A 7-year-old mentally retarded girl died following subacute dermatomyositis. Muscle biopsies supported the clinical diagnosis and revealed paracrystalline inclusions on EM. The brain autopsy showed cerebral and cerebellar polymicrogyria. The clinico-pathological findings in this child are related to similar previously reported data in her older sister. The possibility of a new autosomal recessive syndrome involving both fetal brain development and childhood immunological function is discussed.


Assuntos
Encéfalo/anormalidades , Aberrações Cromossômicas/genética , Dermatomiosite/genética , Genes Recessivos/genética , Atrofia , Biópsia , Encéfalo/patologia , Tronco Encefálico/anormalidades , Tronco Encefálico/patologia , Cerebelo/anormalidades , Cerebelo/patologia , Córtex Cerebral/anormalidades , Córtex Cerebral/patologia , Criança , Aberrações Cromossômicas/patologia , Transtornos Cromossômicos , Dermatomiosite/patologia , Feminino , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual/patologia , Microscopia Eletrônica , Músculos/patologia , Síndrome
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