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1.
Sci Rep ; 5: 9866, 2015 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-25952133

RESUMO

Transparent and flexible electrodes are widely used on a variety of substrates such as plastics and glass. Yet, to date, transparent electrodes on a textile substrate have not been explored. The exceptional electrical, mechanical and optical properties of monolayer graphene make it highly attractive as a transparent electrode for applications in wearable electronics. Here, we report the transfer of monolayer graphene, grown by chemical vapor deposition on copper foil, to fibers commonly used by the textile industry. The graphene-coated fibers have a sheet resistance as low as ~1 kΩ per square, an equivalent value to the one obtained by the same transfer process onto a Si substrate, with a reduction of only 2.3 per cent in optical transparency while keeping high stability under mechanical stress. With this approach, we successfully achieved the first example of a textile electrode, flexible and truly embedded in a yarn.

5.
JBR-BTR ; 87(2): 73-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15174806

RESUMO

We report the case of a 69-year-old woman presenting with a rapidly enlarging thyroid mass as the first extramedullary symptom of plasmacytoma. Extramedullary locations are found in less than 5% of patients with multiple myeloma and can arise in any tissue. If the patient presents with extramedullary lesions and the radiologist is unaware of the underlying disease process the masses can be mistaken for disseminated metastatic carcinoma or non-Hodgkin's lymphoma.


Assuntos
Mieloma Múltiplo/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Idoso , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Mieloma Múltiplo/diagnóstico por imagem , Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Tomografia Computadorizada por Raios X
6.
Thromb Haemost ; 87(2): 294-9, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11858490

RESUMO

The molecular basis of Factor V deficiency has been defined in few patients only. We report a homozygous nucleotide change (G6395A) in two Tunisian probands with Factor V deficiency and bleeding episodes. This substitution results in the replacement of an arginine (R) by a histidine (H) in amino acid position 2074, located in the Factor V C2-domain. Mutations in this protein domain have not previously been described. Several lines of evidence support that this sequence variant is indeed disease causing: 1) Crystal structures of Factor V and molecular C2-domain modeling studies of H2074 suggest that the conserved R2074 is required for correct folding; 2) Structure-function studies of selective Factor V mutants (R2074A) demonstrate the importance of R2074 for structural stability of the Factor V C2-domain and for cofactor activity (1); 3) In Factor VIII, point mutations in codon 2209, which corresponds to position 2074 in Factor V, cause hemophilia A.


Assuntos
Substituição de Aminoácidos , Deficiência do Fator V/genética , Fator V/genética , Mutação de Sentido Incorreto , Mutação Puntual , Sequência de Aminoácidos , Consanguinidade , Doenças em Gêmeos , Fator V/química , Feminino , Humanos , Masculino , Modelos Moleculares , Dados de Sequência Molecular , Linhagem , Conformação Proteica , Estrutura Terciária de Proteína , Alinhamento de Sequência , Tunísia
7.
BMC Med Genet ; 2: 11, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11710961

RESUMO

BACKGROUND: Mutations in the fibrillin -1 gene (FBN1) cause Marfan syndrome (MFS), an autosomal dominant multi-system connective tissue disorder. The 200 different mutations reported in the 235 kb, 65 exon-containing gene include only one family with a genomic multi-exon deletion. METHODS: We used long-range RT-PCR for mutation detection and long-range genomic PCR and DNA sequencing for identification of deletion breakpoints, allele-specific transcript analyses to determine stability of the mutant RNA, and pulse-chase studies to quantitate fibrillin synthesis and extracellular matrix deposition in cultured fibroblasts. Southern blots of genomic DNA were probed with three overlapping fragments covering the FBN1 coding exons RESULTS: Two novel multi-exon FBN1 deletions were discovered. Identical nucleotide pentamers were found at or near the intronic breakpoints. In a Case with classic MFS, an in-frame deletion of exons 42 and 43 removed the C-terminal 24 amino acids of the 5th LTBP (8-cysteine) domain and the adjacent 25th calcium-binding EGF-like (6-cysteine) domain. The mutant mRNA was stable, but fibrillin synthesis and matrix deposition were significantly reduced. A Case with severe childhood-onset MFS has a de novo deletion of exons 44-46 that removed three EGF-like domains. Fibrillin protein synthesis was normal, but matrix deposition was strikingly reduced. No genomic rearrangements were detected by Southern analysis of 18 unrelated MFS samples negative for FBN1 mutation screening. CONCLUSIONS: Two novel deletion cases expand knowledge of mutational mechanisms and genotype/phenotype correlations of fibrillinopathies. Deletions or mutations affecting an LTBP domain may result in unstable mutant protein cleavage products that interfere with microfibril assembly.

8.
Brain ; 124(Pt 8): 1544-54, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11459746

RESUMO

Multiple sclerosis is believed to result from a CD4+ T-cell response against myelin antigens. Peptidoglycan, a major component of the Gram-positive bacterial cell wall, is a functional lipopolysaccharide analogue with potent proinflammatory properties and is conceivably a mediator of sterile inflammation. Here we demonstrate that peptidoglycan is present within antigen-presenting cells in the brain of multiple sclerosis patients. These cells have macrophage and dendritic cell characteristics, and are immunocompetent as evidenced by co-expression of inflammatory cytokines and co-stimulatory molecules. In addition, intrathecal plasma cells specific for peptidoglycan are present in multiple sclerosis brain tissue, and antibodies binding peptidoglycan are present in CSF during active disease. Peptidoglycan may thus contribute to T- and B-cell activity during brain inflammation without a requirement for local bacterial replication.


Assuntos
Sistema Nervoso Central/imunologia , Esclerose Múltipla/imunologia , Peptidoglicano/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais , Antígenos de Bactérias/análise , Autopsia , Linfócitos B/imunologia , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Inflamação , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia
9.
Rheumatology (Oxford) ; 40(4): 438-46, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11312384

RESUMO

OBJECTIVES: Peptidoglycan (PG), a component of Gram-positive bacteria, may be involved in rheumatoid arthritis (RA) because of its ability to induce production of proinflammatory cytokines, to induce arthritis in rodents, and its presence in antigen-presenting cells in RA joints. METHODS: In the present study, physiologically relevant PG was able to induce T-cell proliferation in peripheral blood and synovial fluid samples of RA patients, but the magnitude of the response did not differ from that of cells from healthy subjects. In addition, production of cytokines associated with RA (interleukins (IL)-1beta, IL-6, IL-8, IL-10, IL-12 and tumour necrosis factor alpha) and of the matrix metalloproteinase, gelatinase B (MMP-9), was induced in blood and synovial fluid cultures of RA patients. CONCLUSION: The fact that PG, which can be found in synovial tissues of RA patients is able to induce the production of inflammatory mediators supports the hypothesis that PG plays a role in the pathogenesis of RA by influencing the inflammatory microenvironment of the joint.


Assuntos
Artrite Reumatoide/imunologia , Mediadores da Inflamação/metabolismo , Ativação Linfocitária , Peptidoglicano/farmacologia , Linfócitos T/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Citocinas/biossíntese , Feminino , Humanos , Masculino , Metaloproteinase 9 da Matriz/biossíntese , Pessoa de Meia-Idade , Baço/imunologia , Líquido Sinovial/imunologia
10.
Clin Exp Immunol ; 123(1): 140-6, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11168011

RESUMO

The gut flora is believed to play a role in the pathogenesis of RA. Peptidoglycan, a major cell wall component of Gram-positive bacteria, is a candidate antigen because of its capability to trigger production of proinflammatory cytokines, to induce arthritis in rodents, and because of its presence in antigen-presenting cells in RA joints. We investigated whether the systemic and local antibody levels against a peptidoglycan-polysaccharide (PG-PS) are related to the presence and disease activity of RA. Significantly lower levels of systemic IgG directed against PG-PS were found in healthy females compared with healthy males, and systemic IgA levels specific for PG-PS were negatively correlated with age. Levels of systemic IgG directed against PG-PS were significantly reduced in RA patients compared with sex- and age-matched healthy controls. Local (synovial fluid) levels of IgG did not correlate with disease activity whereas synovial fluid levels of IgA correlated positively with disease activity. These data suggest that IgG in healthy people mediates protection against spreading of PG to non-mucosal sites.


Assuntos
Artrite Reumatoide/imunologia , Artrite Reumatoide/metabolismo , Imunoglobulina G/metabolismo , Peptidoglicano/imunologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Artrite Reumatoide/microbiologia , Fezes/química , Fezes/microbiologia , Feminino , Bactérias Gram-Positivas/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Líquido Sinovial/imunologia , Líquido Sinovial/metabolismo
11.
Arthritis Rheum ; 43(10): 2160-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11037875

RESUMO

OBJECTIVE: Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by intimal lining hyperplasia and massive infiltration of the synovial sublining by antigen-presenting cells (APCs), lymphocytes, and plasma cells. Peptidoglycan (PG), a major cell wall component of gram-positive bacteria, which is abundantly expressed in all mucosa, is believed to be involved in the pathogenesis of RA because of its ability to induce the production of proinflammatory cytokines as well as to induce arthritis in rodents. While PG has been detected in APCs in RA joints, little is known about the role of these cells in RA. In this study, the presence and immune competence of PG-containing cells in synovial tissues from 14 RA and 14 osteoarthritis (OA) patients were analyzed in situ. METHODS: Using immunohistochemistry, we examined the coexpression of phenotypic markers, costimulatory molecules, and cytokines by PG-containing cells. RESULTS: PG was present in higher numbers in RA than in OA synovial tissues, although the difference was not significant. PG-containing cells were mainly macrophages, but some mature dendritic cells also contained PG. A high percentage of PG-containing cells in both RA and OA synovial tissues coexpressed HLA-DR. CD40, CD80, and CD86 expression by PG-containing cells was higher in RA than in OA tissues. Furthermore, PG-containing cells coexpressed cytokines, which modulate inflammatory reactions, in particular, tumor necrosis factor alpha and interleukins 6 and 10. CONCLUSION: The results suggest that PG-containing cells may contribute to inflammation within the microenvironment of the joint in RA patients.


Assuntos
Células Apresentadoras de Antígenos/química , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Antígeno B7-1/biossíntese , Citocinas/metabolismo , Bactérias Gram-Positivas/química , Peptidoglicano/análise , Membrana Sinovial/patologia , Adulto , Idoso , Células Apresentadoras de Antígenos/metabolismo , Biomarcadores/análise , Biópsia , Citocinas/biossíntese , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/imunologia , Osteoartrite/patologia , Peptidoglicano/genética , Membrana Sinovial/imunologia
12.
Arthritis Rheum ; 43(3): 593-8, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10728753

RESUMO

OBJECTIVE: The continuous presence of bacteria or their degraded antigens in the synovium may be involved in the pathogenesis of rheumatoid arthritis (RA). The aim of this study was to determine the presence of bacterial nucleic acids and bacterial cell wall constituents in the joints of patients with RA and other forms of arthritis. METHODS: Joint samples were obtained from patients with RA (n = 26), septic arthritis (n = 2), inflammatory osteoarthritis (n = 5), and gout (n = 6), and joint trauma (n = 1). Universal 16S-ribosomal RNA primers were used to detect the presence of bacterial DNA in these samples, using stringent regimens for sample collection and molecular microbiologic analysis. Automated sequencing and comparative data analysis were performed to identify the species. The presence of bacterial peptidoglycan-polysaccharide complexes in synovial tissue was detected by immunohistologic analysis with a specific antibody. RESULTS: The bacterial species cultured from the synovium could be identified in both of the patients with septic arthritis. DNA amplicons were also detected in the synovial fluid and/or tissue samples from 5 patients with RA and 2 patients with crystal-induced arthritis; these originated from multiple bacterial species. Staining for peptidoglycan-polysaccharide complexes was positive in the synovial tissue of both patients with septic arthritis, 16 with RA, 4 with inflammatory osteoarthritis, 4 with crystal-induced arthropathy, and 1 with joint trauma. The staining was mainly found in cells in the synovial sublining, including macrophages. CONCLUSION: The results indicate that bacterial DNA and bacterial cell wall constituents are retained in the joints of some patients with arthritis, where they might enhance synovial inflammation.


Assuntos
Artrite Reumatoide/genética , Artrite/genética , Chlamydia/química , DNA Bacteriano/análise , Articulações/química , Peptidoglicano/análise , RNA Ribossômico 16S/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite Infecciosa/genética , Feminino , Gota/genética , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/genética , Reação em Cadeia da Polimerase , Coloração e Rotulagem , Líquido Sinovial/microbiologia , Membrana Sinovial/microbiologia
13.
J Histochem Cytochem ; 48(1): 95-103, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10653590

RESUMO

Integral immunohistochemical analysis of immune responses in frozen sections requires that, in addition to constitutively expressed membrane CD markers, less stable determinants can be reliably visualized. Therefore, we compared the commonly used acetone fixation method with pararosaniline fixation for six determinant categories. These categories included selected constitutively expressed markers, inducible co-stimulatory molecules, pro- and anti-inflammatory cytokines (including the novel cytokine IL-18, also known as IGIF and IL-1gamma), antigen-specific antibody in plasma cells, bacterial peptidoglycan, and lysosomal acid phosphatase activity. Human spleen and mouse spleen activated by agonistic anti-CD40 antibody or TNP-Ficoll immunization were analyzed in parallel with brain tissue from multiple sclerosis (MS) patients and marmoset monkeys with experimental autoimmune encephalomyelitis (EAE), an animal model for MS. Fixation with pararosaniline resulted in better morphology of all tissues and inhibited endogenous alkaline phosphatase activity in brain tissue. Most determinants could be reliably detected. Staining sensitivity and intensity were markedly increased for selected determinant-tissue combinations, e.g., for IL-4 in human spleen and CD40 in human and mouse spleen. These data show that pararosaniline is a useful alternative to acetone, resulting in superior morphology and specific staining for selected determinant-tissue combinations. This provides additional flexibility for in situ analysis of immune reactivity.


Assuntos
Anticorpos/isolamento & purificação , Antígenos CD/isolamento & purificação , Citocinas/isolamento & purificação , Corantes de Rosanilina , Fixação de Tecidos/métodos , Toluidinas , Animais , Especificidade de Anticorpos , Encéfalo/anatomia & histologia , Callithrix , Encefalomielite Autoimune Experimental , Fixadores , Humanos , Camundongos , Esclerose Múltipla , Plasmócitos , Baço/anatomia & histologia
14.
Am J Hum Genet ; 65(4): 1007-20, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10486319

RESUMO

Fibrillin-1 (FBN1) contains 47 epidermal growth factor (EGF)-like domains characterized by six conserved cysteine residues. Cysteine substitutions that disrupt one of the three disulfide bonds are frequent causes of Marfan syndrome (MFS). We identified 19 new substitutions involving cysteine residues in each of the six positions of EGF-like domains. Allele-specific mRNA assays revealed equal abundance of mutant and normal FBN1 transcripts in all 10 individuals studied. Quantitative pulse-chase analysis of fibrillin protein was performed on 25 mutant fibroblast strains with substitutions of 22 different cysteine residues in 18 different EGF-like domains spanning the entire gene. Normal synthesis and stability of mutant fibrillin molecules was seen in 20/25 individuals, 11 of whom showed delayed intracellular processing and/or secretion. In the remaining five cases, the mutant protein was apparently unstable. In four of these five cases, the second or third disulfide bond of EGF-like domains immediately preceding an 8-cysteine or hybrid domain was affected. All but two mutations caused severe reduction of matrix deposition, which was attributed to a dominant-negative effect of mutant molecules. For genotype/phenotype comparisons, clinical data on 25 probands and 19 mutation-positive family members were analyzed. Ocular manifestations were among the most consistent features (ectopia lentis in 86%, myopia in 80%). Nine mutations encoded by exons 26-32 resulted in early-onset classic MFS and, in one case, neonatal-lethal MFS. Mutations outside this region were associated with variable clinical phenotypes, including individuals with fibrillinopathies not meeting diagnostic criteria for MFS.


Assuntos
Substituição de Aminoácidos/genética , Cisteína/genética , Fator de Crescimento Epidérmico/química , Síndrome de Marfan/genética , Proteínas dos Microfilamentos/genética , Mutação/genética , Adolescente , Adulto , Idade de Início , Idoso , Alelos , Células Cultivadas , Criança , Pré-Escolar , Cisteína/metabolismo , Análise Mutacional de DNA , Dissulfetos/metabolismo , Éxons/genética , Fibrilina-1 , Fibrilinas , Fibroblastos , Genes Letais/genética , Genótipo , Humanos , Recém-Nascido , Síndrome de Marfan/epidemiologia , Síndrome de Marfan/metabolismo , Síndrome de Marfan/fisiopatologia , Proteínas dos Microfilamentos/química , Pessoa de Meia-Idade , Dados de Sequência Molecular , Fenótipo , RNA Mensageiro/análise , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
J Infect Dis ; 179(6): 1459-68, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10228068

RESUMO

Peptidoglycan (PG) is the major component of the cell wall of gram-positive bacteria. In vitro, PG isolated from conventional bacterial cultures can induce secretion of proinflammatory cytokines by human monocytes, indicating that PG may be involved in immune responses against infections by gram-positive bacteria. To investigate the biologic activity of PG in human tissues, an improved method was developed to isolate significant amounts of PG from sterile human spleen tissue. Biochemical analysis demonstrated that PG isolated from human spleen is largely intact. Human whole blood cell cultures were able to produce the proinflammatory cytokines tumor necrosis factor-alpha and interleukin-1 and -6 after stimulation with PG isolated from human spleen. Cytokine induction was not sensitive to inhibition by polymyxin B, in contrast to lipopolysaccharide. Collectively, the data show that intact PG in sterile human tissue is biologically active and may induce local proinflammatory cytokine production.


Assuntos
Células Sanguíneas/imunologia , Citocinas/biossíntese , Bactérias Gram-Positivas/imunologia , Mediadores da Inflamação/metabolismo , Peptidoglicano/imunologia , Baço/imunologia , Células Apresentadoras de Antígenos , Humanos , Técnicas In Vitro , Interleucina-1/biossíntese , Interleucina-6/biossíntese , Ácidos Murâmicos/análise , Peptidoglicano/farmacologia , Baço/citologia , Baço/efeitos dos fármacos , Fator de Necrose Tumoral alfa/biossíntese
16.
Antimicrob Agents Chemother ; 42(12): 3073-8, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9835493

RESUMO

Antibiotics with different mechanisms of action may vary with respect to their effects on the release and immunostimulatory activities of cell wall fragments from gram-positive bacteria. Therefore, after Staphylococcus aureus was cultured for 4 h in the absence of antibiotics (control) and in the presence of beta-lactam antibiotics (imipenem, flucloxacillin, or cefamandole) and protein synthesis-inhibiting antibiotics (erythromycin, clindamycin, or gentamicin), the lipoteichoic acid (LTA) and peptidoglycan (PG) levels in the bacterial supernatants were measured. beta-Lactam antibiotics greatly enhanced the release of LTA and PG (4- to 9-fold and 60- to 85-fold, respectively), whereas protein synthesis inhibitors did not affect PG release and even inhibited the release of LTA compared to the amount of LTA released in control cultures. The capacity of beta-lactam supernatants to stimulate the production of tumor necrosis factor alpha and interleukin-10 in human whole blood was significantly higher than that of protein synthesis inhibitor or control supernatants; the amounts of these cytokines released were directly proportional to the concentrations of PG and LTA in the supernatants. Enzymatic degradation of PG in the supernatants indicated that PG was mainly responsible for the observed biological reactivity.


Assuntos
Antibacterianos/farmacologia , Lipopolissacarídeos/metabolismo , Peptidoglicano/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Ácidos Teicoicos/metabolismo , Parede Celular/imunologia , Parede Celular/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , Técnicas In Vitro , Interleucina-10/sangue , Lactamas , Lipopolissacarídeos/imunologia , Testes de Sensibilidade Microbiana , Peptidoglicano/imunologia , Inibidores da Síntese de Proteínas/farmacologia , Staphylococcus aureus/imunologia , Staphylococcus aureus/metabolismo , Ácidos Teicoicos/imunologia , Fator de Necrose Tumoral alfa/biossíntese
18.
Hum Genet ; 99(5): 607-11, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9150726

RESUMO

In individuals with the Marfan syndrome (MFS), mutations have been identified in the fibrillin-1 gene (FBN1) at 15q21.1. A proline-to-alanine change at position 1148 in exon 27 (Pro1148Ala) has been reported in probands with MFS, aortic aneurysm or Marfanoid-craniosynostosis. It was suggested that this mutation could be a risk factor for aortic dilatation, since it was rarely observed in control populations. To investigate further the pathogenicity of this substitution, we screened 416 unrelated control individuals by allele-specific oligonucleotide (ASO) hybridization. We found 16 individuals who carried the alanine allele (3.8%), 3 of whom were homozygous. Five were of Latin American and eight were of Asian extraction. We also screened 133 probands with MFS, aortic aneurysm or related connective tissue disorders and found 4 (3%) that were heterozygous for the 1148Ala allele. All positive results were confirmed by DNA sequencing. In 20 individuals with 1148Ala, we confirmed the association with the rarer A allele at the IVS27-5G-->A polymorphism. Our results suggest that the Pro1148Ala change is a polymorphism of ancient evolutionary origin that is more prevalent in Asian and Latin American than in Caucasian or African populations.


Assuntos
Alanina , Aneurisma Aórtico/genética , Cromossomos Humanos Par 15 , Síndrome de Marfan/genética , Proteínas dos Microfilamentos/genética , Mutação Puntual , Polimorfismo Genético , Prolina , Sequência de Aminoácidos , Animais , Ásia/etnologia , Sequência de Bases , Evolução Biológica , Bovinos , Células Cultivadas , Mapeamento Cromossômico , Doenças do Tecido Conjuntivo/genética , Primers do DNA , Suscetibilidade a Doenças , Drosophila/genética , Éxons , Fibrilina-1 , Fibrilinas , Homozigoto , Humanos , Íntrons , América Latina/etnologia , Camundongos , Proteínas dos Microfilamentos/química , Reação em Cadeia da Polimerase , Grupos Raciais , Valores de Referência , Pele , Estados Unidos
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