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1.
Invertebr Syst ; 382024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38744500

RESUMO

The integration of morphological and molecular lines of evidence has enabled the family Deltocyathidae to be erected to accommodate Deltocyathus species that were previously ascribed to the family Caryophylliidae. However, although displaying the same morphological characteristics as other species of Deltocyathus , molecular data suggested that D. magnificus was phylogenetically distant from Deltocyathidae, falling within the family Turbinoliidae instead. To elucidate the enigmatic evolutionary history of this species and skeletal microstructural features, the phylogenetic relationships of Deltocyathidae and Turbinoliidae were investigated using nuclear ultraconserved and exon loci and complete mitochondrial genomes. Both nuclear and mitochondrial phylogenomic reconstructions confirmed the position of D. magnificus within turbinolids. Furthermore, a novel mitochondrial gene order was uncovered for Deltocyathidae species. This gene order was not present in Turbinoliidae or in D. magnificus that both have the scleractinian canonical gene order, further indicating the taxonomic utility of mitochondrial gene order. D. magnificus is therefore formally moved to the family Turbinoliidae and accommodated in a new genus (Dennantotrochus Kitahara, Vaga & Stolarski, gen. nov.). Surprisingly, turbinolids and deltocyathids do not differ in microstructural organisation of the skeleton that consists of densely packed, individualised rapid accretion deposits and thickening deposits composed of fibres perpendicular to the skeleton surface. Therefore, although both families are clearly evolutionarily divergent, macromorphological features indicate a case of skeletal convergence while these may still share conservative biomineralisation mechanisms. ZooBank: urn:lsid:zoobank.org:pub:5F1C0E25-3CC6-4D1F-B1F0-CD9D0014678E.


Assuntos
Antozoários , Filogenia , Animais , Antozoários/genética , Antozoários/classificação , Genoma Mitocondrial/genética , Evolução Biológica
2.
Mol Phylogenet Evol ; 175: 107565, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35787457

RESUMO

Molecularly, the family Caryophylliidae is polyphyletic and different sets of genetic data converge towards a consensus that a taxonomic review of this family is necessary. Overall, the order of genes in the mitochondrial genome (mitogenome) together with DNA sequences have been used to successfully untangle evolutionary relationships in several groups of organisms. Published mitogenomes of two caryophylliid genera (Desmophyllum and Solenosmilia) present a transposition of the gene block containing cob, nad2, and nad6, which is located between nad5 5' exon and trnW, while that of Polycyathus chaishanensis presents the same gene order as the majority of scleractinian corals. In molecular-based evolutionary reconstructions, caryophylliids that have the mitochondrial gene rearrangement were recovered as a monophyletic lineage ("true" caryophylliids), while members of the genus Polycyathus were placed in a different position. In this study, additional mitogenomes of this family were assembled and included in evolutionary reconstructions of Scleractinia in order to improve our understanding on whether the mitogenome gene rearrangement is limited to and, therefore, could be a synapomorphy of the actual members of Caryophylliidae. Specimens of Caryophyllia scobinosa, Premocyathus sp., Heterocyathus sulcatus, and Trochocyathus caryophylloides, as well as Desmophyllum pertusum and Solenosmilia variabilis from the Southwest Atlantic were sequenced using Illumina platforms. Then, mitochondrial genomes were assembled and annotated, and nuclear datasets were recovered in-silico from assembled contigs using a previously published set of baits. Evolutionary reconstructions were performed using mitochondrial and nuclear datasets and based on Maximum Likelihood and Bayesian Inference. Obtained mitogenomes are circular and range between 15,816 and 18,225 bp in size and from 30.76% to 36.63% in GC content. The gene rearrangement is only seen in C. scobinosa, D. pertusum, Premocyathus sp., and S. variabilis, which were recovered as a monophyletic clade in both mitochondrial and nuclear phylogenies. On the other hand, the "caryophylliids" with the canonical mitogenome gene order were not recovered within this clade. Differences in features of the skeleton of "true" caryophylliids in comparison to traditional members of the family were observed and offer further support that the gene rearrangement might be seen as a synapomorphy of family Caryophylliidae.


Assuntos
Antozoários , Genoma Mitocondrial , Animais , Antozoários/genética , Teorema de Bayes , Ordem dos Genes , Genes Mitocondriais , Filogenia
3.
Sci Rep ; 8(1): 1429, 2018 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-29362434

RESUMO

The aim of this work was to investigate the structural features of type I collagen isoforms and collagen-based films at atomic and molecular scales, in order to evaluate whether and to what extent different protocols of slurry synthesis may change the protein structure and the final properties of the developed scaffolds. Wide Angle X-ray Scattering data on raw materials demonstrated the preferential orientation of collagen molecules in equine tendon-derived collagens, while randomly oriented molecules were found in bovine skin collagens, together with a lower crystalline degree, analyzed by the assessment of FWHM (Full Width at Half Maximum), and a certain degree of salt contamination. WAXS and FT-IR (Fourier Transform Infrared) analyses on bovine collagen-based films, showed that mechanical homogenization of slurry in acidic solution was the treatment ensuring a high content of super-organization of collagen into triple helices and a high crystalline domain into the material. In vitro tests on rat Schwannoma cells showed that Schwann cell differentiation into myelinating cells was dependent on the specific collagen film being used, and was found to be stimulated in case of homogenization-treated samples. Finally DHT/EDC crosslinking treatment was shown to affect mechanical stiffness of films depending on collagen source and processing conditions.


Assuntos
Colágeno Tipo I/química , Células de Schwann/citologia , Pele/citologia , Tendões/citologia , Alicerces Teciduais/química , Animais , Bovinos , Células Cultivadas , Cavalos , Humanos , Teste de Materiais , Ratos , Medicina Regenerativa , Espalhamento de Radiação , Células de Schwann/química , Pele/química , Tendões/química , Resistência à Tração , Engenharia Tecidual/métodos
4.
Eur J Neurol ; 22(11): 1474-81, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26176978

RESUMO

BACKGROUND AND PURPOSE: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. Approximately 5%-10% of cases are familial (FALS) and the remaining are sporadic (SALS). To date FUS mutations are responsible for 4%-6% of familial cases as well as 0.7%-1.8% of sporadic cases. METHODS: The frequency of FUS mutations was investigated in an Italian cohort of 500 SALS and 40 FALS patients through direct sequencing of exons 5, 6, 13, 14 and 15. RESULTS: Eight FUS mutation carriers were identified in five SALS (1%) and three FALS (7.5%), five already known and three new mutations: a de novo mutation was identified in a sporadic subject as well as the co-presence of FUS/C9ORF72 mutations in a FALS subject. The molecular and clinical details of the three patients harbouring a novel mutation (G245V, G509D and R491C) are presented here. Moreover the co-presence of the R491C mutation and C9ORF72 pathological expansion was found according to the oligogenic disease model. CONCLUSIONS: In conclusion our results revealed a higher frequency of FUS mutation carriers (7.5%) in FALS compared to literature data together with a higher presence of female gender.


Assuntos
Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/fisiopatologia , Proteína FUS de Ligação a RNA/genética , Adulto , Idoso , Estudos de Coortes , Éxons , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Mutação , Fatores Sexuais
5.
Diabetologia ; 53(1): 160-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19847394

RESUMO

AIMS/HYPOTHESIS: Normal mitochondrial activity is a critical component of neuronal metabolism and function. Disruption of mitochondrial activity by altered mitochondrial fission and fusion is the root cause of both neurodegenerative disorders and Charcot-Marie-Tooth type 2A inherited neuropathy. This study addressed the role of mitochondrial fission in the pathogenesis of diabetic neuropathy. METHODS: Mitochondrial biogenesis and fission were assayed in both in vivo and in vitro models of diabetic neuropathy. Gene, protein, mitochondrial DNA and ultrastructural analyses were used to assess mitochondrial biogenesis and fission. RESULTS: There was greater mitochondrial biogenesis in dorsal root ganglion neurons from diabetic compared with non-diabetic mice. An essential step in mitochondrial biogenesis is mitochondrial fission, regulated by the mitochondrial fission protein dynamin-related protein 1 (DRP1). Evaluation of diabetic neurons in vivo indicated small, fragmented mitochondria, suggesting increased fission. In vitro studies revealed that short-term hyperglycaemic exposure increased levels of DRP1 protein. The influence of hyperglycaemia-mediated mitochondrial fission on cell viability was evaluated by knockdown of Drp1 (also known as Dnm1l). Knockdown of Drp1 resulted in decreased susceptibility to hyperglycaemic damage. CONCLUSIONS/INTERPRETATION: We propose that: (1) mitochondria undergo biogenesis in response to hyperglycaemia, but the increased biogenesis is insufficient to accommodate the metabolic load; (2) hyperglycaemia causes an excess of mitochondrial fission, creating small, damaged mitochondria; and (3) reduction of aberrant mitochondrial fission increases neuronal survival and indicates an important role for the fission-fusion equilibrium in the pathogenesis of diabetic neuropathy.


Assuntos
DNA Mitocondrial/metabolismo , Diabetes Mellitus Experimental/metabolismo , Mitocôndrias/ultraestrutura , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Bromodesoxiuridina/metabolismo , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Técnicas de Cultura de Células , Sobrevivência Celular , DNA Mitocondrial/genética , Proteínas Quinases Associadas com Morte Celular , Diabetes Mellitus Experimental/patologia , GTP Fosfo-Hidrolases/genética , Gânglios Espinais/embriologia , Gânglios Espinais/patologia , Regulação da Expressão Gênica , Glutamina/farmacologia , Hemoglobinas Glicadas/metabolismo , Camundongos , MicroRNAs/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neurônios/citologia , Estresse Oxidativo
6.
J Autoimmun ; 32(2): 79-84, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19171463

RESUMO

OBJECTIVE: Serum IgG antibodies (Abs) to phosphorylated ribosomal (P ribosomal) proteins have been inconsistently associated with neuropsychiatric manifestations in systemic lupus erythematosus (SLE). Our aim was to assess whether serum IgG Abs to ribosomal P proteins are associated with neuropsychiatric SLE. PATIENTS AND METHODS: We examined an inception cohort of 219 SLE patients. Neuropsychiatric SLE manifestations were characterized using the American College of Rheumatology (ACR) definition. Serum Abs to P ribosomal proteins were searched for by immunoblotting. In a subgroup of patients, Abs were investigated also in cerebrospinal fluid (CSF). RESULTS: Abs to P ribosomal proteins were detected in 45 (21%) patients, 23 of whom (51%) with neuropsychiatric involvement. Abs to P ribosomal protein were present both in serum and CSF. Abs to P ribosomal proteins significantly correlated with psychosis (p=0.017), mononeuropathy multiplex (p=0.040), malar rash (p=0.004), serum anti-Sm Abs (p=0.042), and lupus anticoagulant (p=0.036). SLE onset age was significantly younger in patients with Abs to P ribosomal proteins. Logistic regression analysis confirmed the relationship between Abs to P ribosomal proteins and psychosis, malar rash, SLE onset age and lupus anticoagulant. CONCLUSIONS: Abs to ribosomal P proteins are associated with psychosis and might be associated with peripheral nervous system complications.


Assuntos
Anticorpos/imunologia , Vasculite Associada ao Lúpus do Sistema Nervoso Central/imunologia , Proteínas Ribossômicas/imunologia , Adolescente , Adulto , Idoso , Anticorpos/sangue , Anticorpos/líquido cefalorraquidiano , Criança , Estudos de Coortes , Feminino , Seguimentos , Humanos , Vasculite Associada ao Lúpus do Sistema Nervoso Central/sangue , Vasculite Associada ao Lúpus do Sistema Nervoso Central/líquido cefalorraquidiano , Vasculite Associada ao Lúpus do Sistema Nervoso Central/epidemiologia , Masculino , Pessoa de Meia-Idade
7.
Neurology ; 71(5): 322-31, 2008 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-18663178

RESUMO

OBJECTIVE: Recent evidence in animal models suggests that components of the extracellular matrix (ECM) play a primary role in peripheral nerve degeneration and regeneration. METHODS: We investigated the expression of several ECM molecules in human sural nerves by immunohistochemistry, Western blot, and reverse transcriptase PCR analysis. To unravel the possible role of these molecules in nerve regeneration, we compared results obtained from nerves with abundant signs of regeneration with those with complete absence of axonal regeneration. The role of some ECM components on neurite extension was further tested in dorsal root ganglion cultures. RESULTS: We observed that the ECM composition significantly differs in regenerating compared with nonregenerating nerves, independently from their etiologic background. Fibronectin was abundantly expressed in regenerating nerves, whereas vitronectin and fibrin(ogen) prevailed in nonregenerating nerves. Whereas fibronectin is secreted by endoneurial cells, in vivo and vitro studies showed that the source of vitronectin and fibrin(ogen) is the bloodstream. CONCLUSIONS: These data indicate that nerve regeneration is impaired in the presence of breaches in the blood-nerve barrier or impaired extracellular matrix (ECM) degradation that leads to accumulation of plasma vitronectin and fibrin(ogen). The transformation into mature, fibronectin-enriched ECM is necessary for efficient nerve regeneration in humans.


Assuntos
Axônios/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Matriz Extracelular/metabolismo , Regeneração Nervosa/fisiologia , Nervos Periféricos/metabolismo , Doenças do Sistema Nervoso Periférico/metabolismo , Adulto , Idoso , Axônios/patologia , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/fisiopatologia , Western Blotting , Células Cultivadas , Proteínas da Matriz Extracelular/genética , Feminino , Fibrinogênio/genética , Fibrinogênio/metabolismo , Fibronectinas/genética , Fibronectinas/metabolismo , Gânglios Espinais/citologia , Gânglios Espinais/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Nervos Periféricos/patologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Vitronectina/genética , Vitronectina/metabolismo
9.
Int J Immunopathol Pharmacol ; 21(1): 61-71, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18336732

RESUMO

Some inflammatory mediators play an important role not only in the pathogenesis of the inflammatory pain, but also in that of neuropathic and visceral pain. We previously showed the antihyperalgesic effect of oATP, the inhibitor of the P2X7 receptors for the pro-nociceptive ATP, in experimental inflammation. Here we show the antihyperalgesic effect of oATP in mouse models of neuropathic and visceral pain, other than in a model of arthritic pain mimicking rheumatoid arthritis in humans. We also show that mice lacking P2X7 receptors (KO) are resistant to hyperalgesic thermal stimuli following the induction of arthritic, neuropathic and visceral pain. Local (injection into the right hind paw) pre-treatment with oATP is able to prevent the successive induction of ATP-dependent hyperalgesia in wild type mice. In addition, KO mice are not insensitive to intraplantar treatment with ATP. Our data suggest that, even if oATP is able to inhibit purinoceptors different from P2X7, the latter are the more important involved in pain transmission.


Assuntos
Trifosfato de Adenosina/análogos & derivados , Hiperalgesia/tratamento farmacológico , Receptores Purinérgicos P2/fisiologia , Trifosfato de Adenosina/farmacologia , Trifosfato de Adenosina/uso terapêutico , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neuralgia/tratamento farmacológico , Limiar da Dor/efeitos dos fármacos , Antagonistas do Receptor Purinérgico P2 , Receptores Purinérgicos P2X7
10.
Hum Gene Ther ; 18(9): 821-36, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17845130

RESUMO

Successful gene therapy approaches for metachromatic leukodystrophy (MLD), based either on hematopoietic stem/progenitor cells (HSPCs) or direct central nervous system (CNS) gene transfer, highlighted a requirement for high levels of arylsulfatase A (ARSA) expression to achieve correction of disease manifestations in the mouse model. Full assessment of the safety of ARSA expression above physiological levels thus represents a prerequisite for clinical translation of these approaches. Here, using lentiviral vectors (LVs), we generated two relevant models for the stringent evaluation of the consequences of ARSA overexpression in transduced cells. We first demonstrated that ARSA overexpression in human HSPCs does not affect their clonogenic and multilineage differentiation capacities in clonogenic assays and in a neonatal hematochimeric mouse model. Further, we studied ARSA overexpression in all body tissues by generating transgenic mice overexpressing the ARSA enzyme by LV up to 15-fold above the normal range and carrying multiple copies of LV in their genome. Characterization of these mice demonstrated the safety of ARSA overexpression in two main gene therapy targets, HSPCs and neurons, with maintenance of the complex functions of the hematopoietic and nervous system in the presence of supraphysiological enzyme levels. The activity of other sulfatases dependent on the same common activator, sulfatase-modifying factor-1 (SUMF1), was tested in ARSA-overexpressing HSPCs and in transgenic mice, excluding the occurrence of saturation phenomena. Overall, these data indicate that from the perspective of clinical translation, therapeutic levels of ARSA overexpression can be safely achieved. Further, they demonstrate an experimental platform for the preclinical assessment of the safety of new gene therapy approaches.


Assuntos
Cerebrosídeo Sulfatase/metabolismo , Terapia Genética , Leucodistrofia Metacromática/genética , Leucodistrofia Metacromática/terapia , Animais , Animais Recém-Nascidos , Antígenos CD34/imunologia , Antígenos CD34/metabolismo , Southern Blotting , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Cerebrosídeo Sulfatase/efeitos adversos , Cerebrosídeo Sulfatase/análise , Ensaio de Unidades Formadoras de Colônias , Estudos de Viabilidade , Vetores Genéticos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Lentivirus/genética , Leucodistrofia Metacromática/metabolismo , Leucodistrofia Metacromática/patologia , Camundongos , Camundongos Transgênicos , Modelos Animais , Neurônios/citologia , Neurônios/metabolismo , Reação em Cadeia da Polimerase , Baço/citologia , Transdução Genética
11.
J Neuroimmunol ; 190(1-2): 8-17, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17714795

RESUMO

Clusterin is a protein involved in multiple biological events, including neuronal cytoprotection, membrane recycling and regulation of complement-mediated membrane attack after injury. We investigated the effect of recombinant human clusterin in preclinical models of peripheral neuropathies. Daily treatment with clusterin accelerated the recovery of nerve motor evoked potential parameters after sciatic nerve injury. Prophylactic or therapeutic treatment of experimental autoimmune neuritis rats with clusterin also accelerated the rate of recovery from the disease, associated with remyelination of demyelinated nerve fibers. These data demonstrate that clusterin is capable of ameliorating clinical, neurophysiological and pathological signs in models of peripheral neuropathies.


Assuntos
Clusterina/farmacologia , Fatores de Crescimento Neural/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Nervos Periféricos/efeitos dos fármacos , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Animais , Clusterina/imunologia , Clusterina/uso terapêutico , Citocinas/efeitos dos fármacos , Citocinas/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/fisiopatologia , Feminino , Hipocampo/imunologia , Hipocampo/metabolismo , Hipocampo/patologia , Camundongos , Camundongos Endogâmicos C57BL , Proteína Básica da Mielina/efeitos dos fármacos , Proteína Básica da Mielina/imunologia , Proteína Básica da Mielina/metabolismo , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/imunologia , Bainha de Mielina/patologia , Fatores de Crescimento Neural/imunologia , Fatores de Crescimento Neural/uso terapêutico , Regeneração Nervosa/imunologia , Neurônios/efeitos dos fármacos , Neurônios/imunologia , Neurônios/patologia , Técnicas de Cultura de Órgãos , Nervos Periféricos/imunologia , Nervos Periféricos/fisiopatologia , Doenças do Sistema Nervoso Periférico/imunologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Neuropatia Ciática/tratamento farmacológico , Neuropatia Ciática/imunologia , Neuropatia Ciática/fisiopatologia , Resultado do Tratamento
12.
Neurology ; 69(12): 1285-92, 2007 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-17377071

RESUMO

BACKGROUND: Mutations in the LMNA gene, encoding human lamin A/C, have been associated with an increasing number of disorders often involving skeletal and cardiac muscle, but no clear genotype/phenotype correlation could be established to date. METHODS: We analyzed the LMNA gene in a large cohort of patients mainly affected by neuromuscular or cardiac disease and clustered mutated patients in two groups to unravel possible correlations. RESULTS: We identified 28 variants, 9 of which reported for the first time. The two groups of patients were characterized by clinical and genetic differences: 1) patients with childhood onset displayed skeletal muscle involvement with predominant scapuloperoneal and facial weakness associated with missense mutations; 2) patients with adult onset mainly showed cardiac disorders or myopathy with limb girdle distribution, often associated with frameshift mutations presumably leading to a truncated protein. CONCLUSIONS: Our findings, supported by meta-analysis of previous literature, suggest the presence of two different pathogenetic mechanisms: late onset phenotypes may arise through loss of function secondary to haploinsufficiency, while dominant negative or toxic gain of function mechanisms may explain the severity of early phenotypes. This model of patient stratification may help patient management and facilitate future studies aimed at deciphering lamin A/C pathogenesis.


Assuntos
Predisposição Genética para Doença/genética , Cardiopatias/genética , Laminas/genética , Mutação/genética , Doenças Neuromusculares/genética , Adulto , Idade de Início , Criança , Pré-Escolar , Análise por Conglomerados , Estudos de Coortes , Análise Mutacional de DNA , Progressão da Doença , Mutação da Fase de Leitura/genética , Marcadores Genéticos/genética , Haplótipos/genética , Cardiopatias/metabolismo , Cardiopatias/fisiopatologia , Humanos , Lamina Tipo A/genética , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Mutação de Sentido Incorreto/genética , Miocárdio/metabolismo , Miocárdio/patologia , Doenças Neuromusculares/metabolismo , Doenças Neuromusculares/fisiopatologia , Fenótipo
13.
J Neurol Neurosurg Psychiatry ; 76(7): 1019-21, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15965218

RESUMO

The coexistence of neurogenic and myogenic features in scapuloperoneal syndrome is rarely ascribed to a single gene. Defects in the nuclear envelope protein lamin A/C, encoded by the LMNA gene, have been shown to be associated with a variety of disorders affecting mainly the muscular and adipose tissues and, more recently, with autosomal recessive Charcot-Marie-Tooth type 2 neuropathy. This report is about a patient presenting features of myopathy and neuropathy due to a dominant LMNA mutation, suggesting that the peripheral nerve might be affected in primary LMNA myopathy. Our observations further support the marked intrafamilial and interfamilial phenotypic heterogeneity associated with lamin A/C defects.


Assuntos
Análise Mutacional de DNA , Genes Dominantes , Laminas/genética , Distrofia Muscular de Emery-Dreifuss/genética , Doenças do Sistema Nervoso Periférico/genética , Adolescente , Adulto , Biópsia , Feminino , Humanos , Lamina Tipo A , Masculino , Músculo Esquelético/inervação , Músculo Esquelético/patologia , Atrofia Muscular/diagnóstico , Atrofia Muscular/genética , Atrofia Muscular/patologia , Distrofia Muscular de Emery-Dreifuss/diagnóstico , Exame Neurológico , Linhagem , Doenças do Sistema Nervoso Periférico/diagnóstico , Doenças do Sistema Nervoso Periférico/patologia , Fenótipo , Nervo Sural/patologia
15.
Neurol Sci ; 24 Suppl 4: S246-50, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14598053

RESUMO

This article reviews the efficacy and tolerability of intravenous immunoglobulins (IVIg) in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), including those forms associated with monoclonal gammopathy (paraproteinemic demyelinating neuropathy, PDN). Class I trials demonstrated that IVIg are effective in CIDP. About two-thirds of patients respond to initial treatment; however, most of them require repeated drug doses to maintain improvement. For PDN there are some evidences that IVIg are efficacious; however, it seems that less than 50% of the patients respond to this treatment and the persistence of the response over time has not been thoroughly investigated. The safety profile of immunoglobulins is generally good; however, the possibility of the occurrence of serious adverse effects should always be considered before starting treatment.


Assuntos
Doenças Desmielinizantes/tratamento farmacológico , Imunoglobulinas Intravenosas/uso terapêutico , Polineuropatias/tratamento farmacológico , Doença Crônica , Humanos , Inflamação/tratamento farmacológico , Paraproteinemias/tratamento farmacológico
16.
J Neurol Neurosurg Psychiatry ; 74(9): 1267-71, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12933932

RESUMO

OBJECTIVES: Hepatitis C virus (HCV) infection is often associated with cryoglobulinaemia (CG). Peripheral neuropathy (PN) is a comparatively common complication of CG associated with HCV infection and it is thought to be attributable to nerve ischaemia. Only few HCV CG patients with PN have been reported. The recent finding of HCV RNA in nerve biopsy specimens has suggested a possible direct role of HCV in the pathogenesis of PN. The authors studied 51 HCV patients to determine the prevalence of CG and to clarify the possible mechanism by which HCV determines the PN. METHODS: All the patients were studied clinically, by laboratory tests and electrophysiologically. Twenty eight patients underwent sural nerve biopsy where both morphological and morphometric evaluation of the biopsy specimen was performed, as well as statistical analysis. RESULTS: CG was found in 40 of 51 cases (78%). Polyneuropathy was significantly prevalent in CG+ patients compared with CG- (18 of 40 compared with 1 of 11 patients; p=0.01). HCV CG- patients more frequently developed well defined mononeuropathy or multiple neuropathy when compared with HCV CG+ (10 of 11 compared with 22 of 40; p<0.03). HCV CG+ patients showed significantly higher proportion of rheumatoid factor positivity (p<0.001) and low C4 levels (p=0.001). Nerve biopsy was performed in 25 of 40 HCV CG+ patients and in 3 of 11 HCV CG- patients: epineurial vasculitis was present in 8 of 25 HCV CG+ (32%) and in 2 of 3 HCV CG-. Differential fascicular loss of axons was found in 10 of 25 CG+ (40%) and 1 of 3 CG-, signs of both demyelination and axonal degeneration were present in 7 of 25 CG+ (28%). No significant difference was found in neuropathological features, while histometrical analysis disclosed more severe involvement in CG+ patients. CONCLUSIONS: These findings suggest that the presence of CG is a negative predictive factor for the associated PN. Morphological findings in the sural nerve from HCV CG- and CG+ are consistent with an ischaemic mechanism of nerve damage and are against a direct role of the virus in causing the associated PN.


Assuntos
Crioglobulinemia/etiologia , Hepacivirus/patogenicidade , Hepatite C/complicações , Doenças do Sistema Nervoso Periférico/etiologia , Doenças do Sistema Nervoso Periférico/virologia , Idoso , Biópsia , Crioglobulinemia/patologia , Crioglobulinemia/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso Periférico/patologia , Prognóstico
17.
Mol Cell Neurosci ; 23(2): 210-8, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12812754

RESUMO

Defects in laminins or laminin receptors are responsible for various neuromuscular disorders, including peripheral neuropathies. Interactions between Schwann cells and their basal lamina are fundamental to peripheral nerve development and successful myelination. Selected laminins are expressed in the endoneurium, and their receptors are developmentally regulated during peripheral nerve formation. Loss-of-function mutations have confirmed the importance and the role of some of these molecules. Here we show for the first time that another laminin receptor, alpha7beta1 integrin, previously described only in neurons, is also expressed in Schwann cells. The expression of alpha7 appears postnatally, such that alpha7beta1 is the last laminin receptor expressed by differentiating Schwann cells. Genetic inactivation of the alpha7 subunit in mice does not affect peripheral nerve formation or the expression of other laminin receptors. Of note, alpha7beta1 is not necessary for basal lamina formation and myelination. Nonetheless, these data taken together with the previous demonstration of impaired axonal regrowth in alpha7-null mice suggest a possible Schwann cell-autonomous role for alpha7 in nerve regeneration.


Assuntos
Integrinas/biossíntese , Bainha de Mielina/metabolismo , Fibras Nervosas Mielinizadas/metabolismo , Nervos Periféricos/crescimento & desenvolvimento , Nervos Periféricos/metabolismo , Células de Schwann/metabolismo , Animais , Animais Recém-Nascidos , Membrana Basal/metabolismo , Membrana Basal/patologia , Membrana Basal/ultraestrutura , Células Cultivadas , Regulação da Expressão Gênica no Desenvolvimento/genética , Imuno-Histoquímica , Integrinas/deficiência , Integrinas/genética , Laminina/genética , Laminina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica , Bainha de Mielina/ultraestrutura , Miopatias Congênitas Estruturais/genética , Miopatias Congênitas Estruturais/metabolismo , Miopatias Congênitas Estruturais/patologia , Fibras Nervosas Mielinizadas/ultraestrutura , Regeneração Nervosa/genética , Nervos Periféricos/ultraestrutura , Doenças do Sistema Nervoso Periférico/genética , Doenças do Sistema Nervoso Periférico/metabolismo , Doenças do Sistema Nervoso Periférico/fisiopatologia , Ratos , Ratos Sprague-Dawley , Células de Schwann/ultraestrutura , Raízes Nervosas Espinhais/crescimento & desenvolvimento , Raízes Nervosas Espinhais/metabolismo , Raízes Nervosas Espinhais/ultraestrutura
18.
Eur Neurol ; 47(4): 196-200, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12037431

RESUMO

A proportion of patients with peripheral neuropathies has circulating autoantibodies directed against neural antigens. In some cases, autoantibodies may play a pathogenic role. We studied a patient with a progressive sensory-motor axonal neuropathy of unknown etiology, looking for circulating autoantibodies against neural antigens and we showed that the patient's serum contained anti-amphiphysin I (AMP I) and amphiphysin II (AMP II) autoantibodies. A sural nerve biopsy revealed an axonal neuropathy. Indirect immunofluorescence experiments with the patient's serum showed a staining of rat axons due to alpha-AMP I autoantibodies and a specific labelling of cytoplasm and Schmidt-Lanterman incisures of Schwann cells due to alpha-AMP II autoantibodies. In conclusion we identified a patient affected by a sensory-motor neuropathy with autoantibodies against both AMP I and AMP II.


Assuntos
Autoanticorpos/imunologia , Neuropatias Hereditárias Sensoriais e Autônomas/imunologia , Proteínas do Tecido Nervoso/imunologia , Idoso , Western Blotting , Imunofluorescência , Neuropatias Hereditárias Sensoriais e Autônomas/fisiopatologia , Humanos , Masculino , Neurônios Motores/patologia , Condução Nervosa/fisiologia
19.
Cereb Cortex ; 12(4): 446-51, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11884359

RESUMO

The patterns of cortical activation evoked by tactile and mechanical painful stimulation in six normal subjects and three patients with complete resection of the corpus callosum are described and compared, with emphasis on the parietal operculum. Stimulus-related cortical activation was investigated by functional magnetic resonance imaging. In both groups, painful stimulation activated the first somatosensory, insular and cingulate cortices in the contralateral hemisphere, and the parietal opercular cortex in both hemispheres. Comparison between the two patterns of cortical activation demonstrated that ipsilateral activation by unilateral painful stimulation is at least partially independent of the corpus callosum and suggests a different organization of the pain and touch systems.


Assuntos
Corpo Caloso/fisiologia , Lobo Parietal/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Corpo Caloso/cirurgia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Procedimentos Neurocirúrgicos , Dor/fisiopatologia , Lobo Parietal/anatomia & histologia , Estimulação Física
20.
J Neuroimmunol ; 114(1-2): 213-9, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11240034

RESUMO

Increased titers of IgM anti-GM1 antibodies are present in some patients with Lower Motor Neuron Disease (LMND) or Motor Neuropathy (MN), but their pathogenic role and the mechanism of action are unclear. Previous studies have shown that the B subunit of Cholera Toxin (CT), which binds and crosslinks ganglioside GM1, modulate intracellular calcium in murine neuroblastoma cells via the activation of L-type voltage-dependent calcium channels (VGCC). Therefore, using a fluorimetric approach, we have examined the hypothesis that the pentameric IgM anti-GM1 antibodies, could similarly alter calcium concentration in N18 neuroblastoma cells. Sera with human IgM anti-GM1 antibodies were obtained from 5 patients with LMND and 2 patients with MN. Human IgG anti-GM1, IgM anti-Myelin Associated Glycoprotein (MAG), IgM anti-sulfatide antibodies and lectin peanut agglutinin (PNA), that recognizes specifically the Gal(betal-3)GalNAc epitope, were used as control sera. Direct application of either human IgM anti-GM1 antibodies or the B subunit of CT to N18 neuroblastoma cells induced a sustained influx of manganese ions, as indicated by a quench of the intracellular fura-2 fluorescence. Furthermore, the dihydropyridine L-type channel antagonists completely inhibited the manganese influx, suggesting that it is due to activation of an L-type VGCC. The magnitude of the influx was correlated with antibody titers. None of human IgG anti-GM1, IgM anti-MAG, IgM anti-sulfatide antibodies or PNA induce an ion influx, pointing to the selective participation of the pentameric IgM isotype of anti-GM1 in the modulation of L-type calcium channels opening. Given that L-type calcium channels are present on motor neurons, the modulation of L-type calcium channels by IgM GM1 antisera may have important implications in diseases such as LMND and MN.


Assuntos
Autoanticorpos/sangue , Cálcio/metabolismo , Gangliosídeo G(M1)/imunologia , Homeostase/imunologia , Imunoglobulina M/sangue , Neurônios/imunologia , Adulto , Canais de Cálcio/metabolismo , Toxina da Cólera , Humanos , Imunoglobulina G/sangue , Pessoa de Meia-Idade , Doença dos Neurônios Motores/imunologia , Doença dos Neurônios Motores/metabolismo , Neuroblastoma , Neurônios/metabolismo , Células Tumorais Cultivadas
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