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1.
Mult Scler ; 20(8): 1033-41, 2014 07.
Artigo em Inglês | MEDLINE | ID: mdl-24336351

RESUMO

BACKGROUND: Multiple sclerosis (MS) is thought to be caused by T-cell mediated autoimmune dysfunction. Risk of developing MS is influenced by environmental and genetic factors. Modifiable differences in DNA methylation are recognized as epigenetic contributors to MS risk and may provide a valuable link between environmental exposure and inherited genetic systems. OBJECTIVES AND METHODS: To identify methylation changes associated with MS, we performed a genome-wide DNA methylation analysis of CD4+ T cells from 30 patients with relapsing-remitting MS and 28 healthy controls using Illumina 450K methylation arrays. RESULTS: A striking differential methylation signal was observed at chr. 6p21, with a peak signal at HLA-DRB1. After prioritisation, we identified a panel of 74 CpGs associated with MS in this cohort. Most notably we found evidence of a major effect CpG island in DRB1 in MS cases (pFDR < 3 × 10(-3)). In addition, we found 55 non-HLA CpGs that exhibited differential methylation, many of which localise to genes previously linked to MS. CONCLUSIONS: Our findings provide the first evidence for association of DNA methylation at HLA-DRB1 in relation to MS risk. Further studies are now warranted to validate and understand how these findings are involved in MS pathology.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Metilação de DNA , Epigênese Genética , Cadeias HLA-DRB1/genética , Esclerose Múltipla Recidivante-Remitente/genética , Regiões 3' não Traduzidas , Regiões 5' não Traduzidas , Adolescente , Adulto , Estudos de Casos e Controles , Ilhas de CpG , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Cadeias HLA-DRB1/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Esclerose Múltipla Recidivante-Remitente/imunologia , Fenótipo , Fatores de Risco , Adulto Jovem
2.
Neurology ; 77(10): 973-9, 2011 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-21813790

RESUMO

OBJECTIVE: To use a historical placebo control design to determine whether lithium carbonate slows progression of amyotrophic lateral sclerosis (ALS). METHODS: A phase II trial was conducted at 10 sites in the Western ALS Study Group using similar dosages (300-450 mg/day), target blood levels (0.3-0.8 mEq/L), outcome measures, and trial duration (13 months) as the positive trial. However, taking riluzole was not a requirement for study entry. Placebo outcomes in patients matched for baseline features from a large database of recent clinical trials, showing stable rates of decline over the past 9 years, were used as historical controls. RESULTS: The mean rate of decline of the ALS Functional Rating Scale-Revised was greater in 107 patients taking lithium carbonate (-1.20/month, 95% confidence interval [CI] -1.41 to -0.98) than that in 249 control patients (-1.01/month, 95% CI -1.11 to -0.92, p = 0.04). There were no differences in secondary outcome measures (forced vital capacity, time to failure, and quality of life), but there were more adverse events in the treated group. CONCLUSIONS: The lack of therapeutic benefit and safety concerns, taken together with similar results from 2 other recent trials, weighs against the use of lithium carbonate in patients with ALS. The absence of drift over time and the availability of a large database of patients for selecting a matched historical control group suggest that use of historical controls may result in more efficient phase II trials for screening putative ALS therapeutic agents. CLASSIFICATION OF EVIDENCE: This study provided Class IV evidence that lithium carbonate does not slow the rate of decline of function in patients with ALS over 13 months.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/patologia , Progressão da Doença , Carbonato de Lítio/uso terapêutico , Programas de Rastreamento , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Programas de Rastreamento/tendências , Pessoa de Meia-Idade , Projetos de Pesquisa/tendências , Adulto Jovem
3.
Neurology ; 62(6): 1006-8, 2004 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-15037714

RESUMO

The authors conducted a randomized, crossover, double-blind, placebo-controlled pilot study of albuterol in nine boys with dystrophinopathies. Primary outcomes were 1) isometric knee extensor and flexor strength; and 2) manual muscle testing (MMT). Isometric knee extensor strength and MMT scores were significantly higher in patients taking albuterol vs placebo. Therefore, 12-week treatment with extended-release albuterol may increase strength in patients with dystrophinopathies. A larger, double-blind, randomized study is necessary to confirm these results.


Assuntos
Agonistas Adrenérgicos beta/uso terapêutico , Albuterol/uso terapêutico , Distrofia Muscular de Duchenne/tratamento farmacológico , Criança , Estudos Cross-Over , Método Duplo-Cego , Distrofina/genética , Seguimentos , Humanos , Contração Isométrica/efeitos dos fármacos , Masculino , Contração Muscular/efeitos dos fármacos , Distrofia Muscular de Duchenne/genética , Mutação , Projetos Piloto , Resultado do Tratamento
4.
Eur J Clin Invest ; 32(5): 360-71, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12027877

RESUMO

BACKGROUND: Monocyte/macrophages are known to infiltrate the brain of patients with HIV-1 encephalitis (HIVE). In Alzheimer's disease brain, the origin of activated microglia has not been determined. MATERIALS AND METHODS: We employed the antigen retrieval technique, immunocytochemistry, immunofluorescense, and confocal microscopy to identify macrophages and microglia in relation to amyloid-beta plaques and the blood-brain barrier in autopsy brain tissues from patients with Alzheimer's disease (AD) and HIVE. RESULTS: In both conditions, cyclooxygenase-2 positive macrophages and, to a lesser degree, T and B cells infiltrate brain perivascular spaces and neuropil. The macrophages are distinguishable from ramified microglia, and decorate the vessels at the sites of apparent of endothelial tight junction protein ZO-1 disruption. The macrophages also infiltrate amyloid-beta plaques, display intracellular amyloid-beta and are surrounded by amyloid-beta-free lacunae. Furthermore, the macrophages partially encircle the walls of amyloid-beta-containing vessels in amyloid angiopathy, and exhibit intracellular amyloid-beta but not paracellular lacunae. Significantly larger zones of fibrinogen leakage surround the microvessels in HIVE brain tissues compared with AD tissues (P = 0.034), and AD tissues have significantly greater leakage than control tissues (P = 0.0339). The AD group differs from a normal control age-matched group with respect to both the area occupied by CD68 (P = 0.03) and cyclooxygenase-2 immunoreactive cells (P = 0.004). CONCLUSION: In both HIVE and AD, blood-borne activated monocyte/macrophages and lymphocytes appear to migrate through a disrupted blood-brain barrier. The lacunae around macrophages in amyloid-beta plaques but not in vessel walls are consistent with the ability of macrophages to phagocytize and clear amyloid-beta deposits in vitro.


Assuntos
Complexo AIDS Demência/imunologia , Doença de Alzheimer/imunologia , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Barreira Hematoencefálica , Encéfalo/metabolismo , Isoenzimas/metabolismo , Macrófagos/fisiologia , Prostaglandina-Endoperóxido Sintases/metabolismo , Complexo AIDS Demência/metabolismo , Complexo AIDS Demência/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/imunologia , Encéfalo/patologia , Circulação Cerebrovascular , Ciclo-Oxigenase 2 , HIV-1 , Humanos , Imuno-Histoquímica , Linfócitos/fisiologia , Masculino , Proteínas de Membrana , Pessoa de Meia-Idade , Fragmentos de Peptídeos/metabolismo , Junções Íntimas/metabolismo
6.
AIDS Res Hum Retroviruses ; 17(15): 1423-33, 2001 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-11679155

RESUMO

HIV-1 cardiomyopathy has become a major cause of death in AIDS patients, but its pathogenesis is unclear. We used an antigen retrieval technique and immunostaining to investigate the hearts of 15 AIDS patients, of whom 3 had dilated cardiomyopathy. Immunocytochemistry shows infiltration of the left ventricular myocardium with mononuclear cells, ranging from minimal to diagnostic of myocarditis. The infiltrates include macrophages and CD3(+) and CD8(+) T cells. The tight junction protein ZO-1 is disrupted at the site of monocyte-macrophage vascular penetration and the coronary vessels show fibrinogen leakage in the hearts of AIDS patients, but not in the normal heart. A subset of infiltrating macrophages is doubly positive for cyclooxygenase 2 (COX-2) and inducible nitric oxide synthase. HIV-1 peptides gp120 and Nef are expressed in macrophages and T cells, but not in cardiomyocytes. COX-2 is expressed by both gp120-positive and gp120-negative macrophages. The hearts of AIDS patients separate into those showing minimal infiltrates with low COX-2 expression and those with dense infiltrates and high COX-2; all failing hearts are in the latter group. These data suggest that COX-2-activated and HIV-1-infected monocyte-macrophages and T cells play a crucial role in the progression of HIV-1 myocarditis to HIV-1 cardiomyopathy.


Assuntos
Infecções por HIV/enzimologia , HIV-1/fisiologia , Isoenzimas/fisiologia , Ativação Linfocitária/imunologia , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Miocardite/imunologia , Prostaglandina-Endoperóxido Sintases/fisiologia , Linfócitos T/imunologia , Disfunção Ventricular Esquerda/imunologia , Encéfalo/imunologia , Vasos Coronários/imunologia , Ciclo-Oxigenase 2 , Infecções por HIV/complicações , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Isoenzimas/metabolismo , Rim/imunologia , Leucócitos/imunologia , Fígado/imunologia , Macrófagos/virologia , Proteínas de Membrana , Miocardite/complicações , Miocardite/enzimologia , Miocardite/virologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Prostaglandina-Endoperóxido Sintases/metabolismo , Linfócitos T/virologia , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/enzimologia , Disfunção Ventricular Esquerda/virologia
7.
Mol Med ; 7(3): 169-76, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11471553

RESUMO

BACKGROUND: The pathogenesis of HIV-1-related cardiomyopathy is poorly understood, but HIV-1 has been detected in cardiomyocytes. Whether HIV-1 penetrates into the myocardium by infection of coronary artery endothelial cells (CAEC) or using transcellular or paracellular routes across CAEC has not been resolved. MATERIALS AND METHODS: A model of the CAEC barrier was constructed with primary CAEC (derived from human coronary vessels). Polymerase chain reaction (PCR) assay, infectious assay, and immunofluorescence were employed to show abortive nature of HIV-1 infection of CAEC. Tight junction (TJ) and cell adhesion proteins were visualized by immunofluorescence. The time course of HIV-1 invasion was measured by HIV-1 RNA assay. Inulin permeability assay determined paracellular leakage. Transmission electron microscopy demonstrated virus-induced endothelial vacuolization. RESULTS: Despite a strong display on CAEC of CXCR4 and a lesser expression of CCR3 and CCR5, HIV-1 did not productively replicate in CAEC, as shown by infectious assay, immunofluorescence, and electron microscopy. HIV-1 infection of CAEC was abortive with minimal reverse transcription of strong stop DNA and pol but not full-length or two LTR DNA circles. Upon infection of the model with 1 million RNA copies of HIV-1JR-FL, virus penetration 2 hr postinfection (PI) was negligible but increased by 1,750% 24 hr PI. The paracellular permeability increased during this period by only 25%. Neither AOP-RANTES nor v-MIPII significantly reduced HIV-1JR-FL invasion. Virus infection did not alter the integral TJ protein occludin and the TJ-associated protein ZO-1. HIV-1 exposed CAEC and brain microvascular endothelial cells (BMVEC) developed extensive cytoplasmic vacuolization with retroviral-like particles in the vacuoles. CONCLUSIONS: The endothelium is not an impenetrable barrier to HIV-1. The virus opens a transcellular route across coronary and brain endothelia in cytoplasmic vacuoles.


Assuntos
Artérias/virologia , Vasos Coronários/virologia , Endocitose , HIV-1/fisiologia , Artérias/ultraestrutura , Sequência de Bases , Células Cultivadas , Quimiocinas/fisiologia , Vasos Coronários/ultraestrutura , Primers do DNA , Produtos do Gene pol/genética , Repetição Terminal Longa de HIV , Microscopia Eletrônica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica , Replicação Viral
8.
Am J Ophthalmol ; 131(5): 615-9, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11336936

RESUMO

PURPOSE: To describe an association between Vogt-Koyanagi-Harada disease and Guillain-Barré syndrome. METHODS: Case series, describing three patients. RESULTS: In two patients, the disorders had their onsets within 2 weeks of each other; in the third patient, Vogt-Koyanagi-Harada disease occurred after 3 months, as Guillain-Barré syndrome resolved. All three patients had bilateral panuveitis typical of Vogt-Koyanagi-Harada disease. Each also developed well-accepted manifestations of Guillain-Barré syndrome, including paresis of the lower extremities (all patients), paresis of the upper extremities (two patients), paresis of cranial nerves (two patients), areflexia (all patients), and abnormal electromyography findings (two patients). CONCLUSIONS: Vogt-Koyanagi-Harada disease may follow or occur simultaneously with Guillain-Barré syndrome. The fact that these two autoimmune disorders occur together in some patients suggest that they may share common disease mechanisms.


Assuntos
Síndrome de Guillain-Barré/complicações , Síndrome Uveomeningoencefálica/complicações , Adulto , Feminino , Glucocorticoides/uso terapêutico , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome Uveomeningoencefálica/diagnóstico , Síndrome Uveomeningoencefálica/tratamento farmacológico , Acuidade Visual
9.
Muscle Nerve ; 23(6): 874-82, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10842262

RESUMO

We have shown that linear estimates of rates of disease progression (LEP), derived from isometric myometry [grip or foot dorsiflexion (FD) strength] and forced vital capacity (FVC%), are clinically and statistically significant predictors of survival of patients with amyotrophic lateral sclerosis (ALS) from date of disease onset and, except those based on grip strength, of survival from the date of measurement. We tested these results in 2 additional groups of patients: 1) those who participated in a previously reported Protropin (GH) study; and 2) those enrolled in two other clinical trials (group 2). The LEP were derived and tested as predictors of survival. In a Cox proportional hazards model, LEP based on all measures predicted survival from disease onset in both groups of patients. Using cutoff points determined within the original group to stratify patients in the validation groups into faster and slower progressing subgroups resulted in statistically significant separation of survival curves from disease onset in group 2 for all LEP and in group 1 (the GH group) for LEP derived from FD strength; and, for survival from date of measurement in group 2, when stratified by LEP based on FD strength or FVC%. LEP based on data generated by myometry or pulmonary function studies have now been shown to predict survival in 3 unrelated groups of patients with ALS entering clinical trials. Their precise use in clinical trial design needs to be explored further.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/mortalidade , Adulto , Idoso , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/fisiopatologia , Articulação do Tornozelo/fisiologia , Fator Neurotrófico Derivado do Encéfalo/administração & dosagem , Fator Neurotrófico Ciliar/administração & dosagem , Progressão da Doença , Feminino , Força da Mão , Hormônio do Crescimento Humano/administração & dosagem , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Exame Neurológico , Prognóstico , Análise de Sobrevida , Capacidade Vital
10.
Clin Immunol ; 91(1): 68-76, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10219256

RESUMO

Leukocyte infiltration of cerebral vessels in cocaine-associated vasculopathy suggests that cocaine may enhance leukocyte migration. We have investigated cocaine's effects on leukocyte adhesion in human brain microvascular endothelial cell (BMVEC) cultures and monocyte migration in an in vitro blood-brain barrier (BBB) model constructed with BMVEC and astrocytes. Cocaine (10(-5) to 10(-9) M) enhanced adhesion of monocytes and neutrophils to BMVEC. In the BBB model, cocaine (10(-4) to 10(-8) M) enhanced monocyte transmigration. Cocaine increased expression of endothelial adhesion molecules, intercellular adhesion molecule-1 (ICAM-1, CD54), vascular cell adhesion molecule-1 (VCAM-1), and endothelial leukocyte adhesion molecule-1 (ELAM-1) on BMVEC. The peak effect on ICAM-1 expression was between 6 and 18 h after treatment. ICAM-1 was increased by cocaine in BMVEC, but not in human umbilical vein endothelial cells, and the enhancement was greater in a coculture of BMVEC with monocytes. ICAM-1 expression was enhanced by a transcriptional mechanism. Polymyxin B inhibited up-regulation of adhesion molecules by LPS but not by cocaine. In LPS-activated BMVEC/monocyte coculture, cocaine increased secretion of tumor necrosis factor-alpha and interleukin-6. Taken together, these findings indicate that cocaine enhances leukocyte migration across the cerebral vessel wall, in particular under inflammatory conditions, but the effects are variable in different individuals. Cocaine's effects are exerted through a cascade of augmented expression of inflammatory cytokines and endothelial adhesion molecules. These could underlie the cerebrovascular complications of cocaine abuse.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Moléculas de Adesão Celular/biossíntese , Cocaína/toxicidade , Leucócitos/efeitos dos fármacos , Leucócitos/fisiologia , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Astrócitos/fisiologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiologia , Encéfalo/citologia , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/biossíntese , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Humanos , Técnicas In Vitro , Mediadores da Inflamação/metabolismo , Molécula 1 de Adesão Intercelular/biossíntese , Interleucina-6/metabolismo , Leucócitos/citologia , Modelos Neurológicos , Monócitos/citologia , Monócitos/efeitos dos fármacos , Monócitos/fisiologia , Fator de Necrose Tumoral alfa/metabolismo
11.
Mol Med ; 5(12): 795-805, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10666479

RESUMO

BACKGROUND: Chemokine receptors on leukocytes play a key role in inflammation and HIV-1 infection. Chemokine receptors on endothelia may serve an important role in HIV-1 tissue invasion and angiogenesis. MATERIALS AND METHODS: The expression of chemokine receptors in human brain microvascular endothelial cells (BMVEC) and coronary artery endothelial cells (CAEC) in vitro and cryostat sections of the heart tissue was determined by light and confocal microscopy and flow cytometry with monoclonal antibodies. Chemotaxis of endothelia by CC chemokines was evaluated in a transmigration assay. RESULTS: In BMVEC, the chemokine receptors CCR3 and CXCR4 showed the strongest expression. CXCR4 was localized by confocal microscopy to both the cytoplasm and the plasma membrane of BMVEC. In CAEC, CXCR4 demonstrated a strong expression with predominantly periplasmic localization. CCR5 expression was detected both in BMVEC and CAEC but at a lower level. Human umbilical cord endothelial cells (HUVEC) expressed strongly CXCR4 but only weakly CCR3 and CCR5. Two additional CC chemokines, CCR2A and CCR4, were detected in BMVEC and CAEC by immunostaining. Immunocytochemistry of the heart tissues with monoclonal antibodies revealed a high expression of CXCR4 and CCR2A and a low expression of CCR3 and CCR5 on coronary vessel endothelia. Coronary endothelia showed in vitro a strong chemotactic response to the CC chemokines RANTES, MIP-1alpha, and MIP-1beta. CONCLUSIONS: The endothelia isolated from the brain display strongly both the CCR3 and CXCR4 HIV-1 coreceptors, whereas the coronary endothelia express strongly only the CXCR4 coreceptor. CCR5 is expressed at a lower level in both endothelia. The differential display of CCR3 on the brain and coronary endothelia could be significant with respect to the differential susceptibility of the heart and the brain to HIV-1 invasion. In addition, CCR2A is strongly expressed in the heart endothelium. All of the above chemokine receptors could play a role in endothelial migration and repair.


Assuntos
Encéfalo/irrigação sanguínea , Vasos Coronários/metabolismo , Endotélio Vascular/metabolismo , Receptores de Quimiocinas/metabolismo , Adulto , Sequência de Aminoácidos , Movimento Celular , Células Cultivadas , Quimiocina CCL2/fisiologia , Criança , Pré-Escolar , Humanos , Microcirculação/metabolismo , Dados de Sequência Molecular , Receptores CCR2 , Receptores CCR3 , Receptores CCR5/metabolismo , Receptores CXCR4/metabolismo , Receptores de HIV/metabolismo
12.
Clin Immunol Immunopathol ; 89(2): 181-90, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9787120

RESUMO

The effects of cocaine infusion (40 mg) on interferon-gamma (IFN-gamma) and interleukin-10 (IL-10) cytokine secretion were examined in 15 cocaine-dependent subjects. Pre- and postcocaine infusion peripheral blood mononuclear cells (PBMC), stimulated with phytohemagglutinin A, were cultured for 48 h and the cytokines in the supernatant measured by enzyme-linked immunosorbent assay. Cocaine infusion, but not saline infusion, increased IFN-gamma secretion and decreased IL-10 secretion, while, in PBMC collected simultaneously from control subjects, secretion of these cytokines was unaltered. Baseline IFN-gamma levels were lower and IL-10 levels higher in addicted subjects compared to those in control subjects. White blood cell and lymphocyte number and CD4(+) and CD8(+) counts were all increased following cocaine infusion. In vitro cocaine treatment of PBMC from addicted subjects suppressed both IL-10 and IFN-gamma secretion. These data suggest that acute cocaine administration, via both central and peripheral effects, may enhance Th1-type immune responses and inhibit Th2-type responses.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/metabolismo , Cocaína/administração & dosagem , Interferon gama/sangue , Interleucina-10/sangue , Adulto , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Divisão Celular/efeitos dos fármacos , Cocaína/análogos & derivados , Cocaína/urina , Transtornos Relacionados ao Uso de Cocaína/sangue , Citocinas/metabolismo , Feminino , Humanos , Infusões Intravenosas , Interferon gama/efeitos dos fármacos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Cinética , Contagem de Leucócitos/efeitos dos fármacos , Leucócitos Mononucleares/citologia , Contagem de Linfócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Fito-Hemaglutininas/farmacologia
13.
Mol Med ; 4(7): 480-9, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9713826

RESUMO

BACKGROUND: Aside from numerous parenchymal and vascular deposits of amyloid beta (A beta) peptide, neurofibrillary tangles, and neuronal and synaptic loss, the neuropathology of Alzheimer's disease is accompanied by a subtle and chronic inflammatory reaction that manifests itself as microglial activation. However, in Alzheimer's disease, alterations in the permeability of the blood-brain barrier and chemotaxis, in part mediated by chemokines and cytokines, may permit the recruitment and transendothelial passage of peripheral cells into the brain parenchyma. MATERIALS AND METHODS: Human monocytes from different donors were tested for their capacity to differentiate into macrophages and their ability to secrete cytokines and chemokines in the presence of A beta 1-42. A paradigm of the blood-brain barrier was constructed utilizing human brain endothelial and astroglial cells with the anatomical and physiological characteristics observed in vivo. This model was used to test the ability of monocytes/macrophages to transmigrate when challenged by A beta 1-42 on the brain side of the blood-brain barrier model. RESULTS: In cultures of peripheral monocytes, A beta 1-42 induced the secretion of proinflammatory cytokines TNF-alpha, IL-6, IL-1 beta, and IL-12, as well as CC chemokines MCP-1, MIP-1 alpha, and MIP-1 beta, and CXC chemokine IL-8 in a dose-related fashion. In the blood-brain barrier model, A beta 1-42 and monocytes on the brain side potentiated monocyte transmigration from the blood side to the brain side. A beta 1-42 stimulated differentiation of monocytes into adherent macrophages in a dose-related fashion. The magnitude of these proinflammatory effects of A beta 1-42 varied dramatically with monocytes from different donors. CONCLUSION: In some individuals, circulating monocytes/macrophages, when recruited by chemokines produced by activated microglia and macrophages, could add to the inflammatory destruction of the brain in Alzheimer's disease.


Assuntos
Peptídeos beta-Amiloides/farmacologia , Barreira Hematoencefálica , Movimento Celular , Quimiocinas/metabolismo , Monócitos/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Doença de Alzheimer/fisiopatologia , Astrócitos/fisiologia , Diferenciação Celular , Células Cultivadas , Relação Dose-Resposta a Droga , Endotélio Vascular/fisiologia , Humanos , Inflamação , Interleucinas/metabolismo , Macrófagos/citologia , Macrófagos/fisiologia , Modelos Biológicos , Monócitos/citologia , Monócitos/metabolismo , Monócitos/fisiologia , Permeabilidade , Fator de Necrose Tumoral alfa/metabolismo
14.
Adv Exp Med Biol ; 437: 199-205, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9666272

RESUMO

Cocaine has wide-ranging effects on the immune and neuroendocrine systems (Fiala et al., 1996) resembling an inflammatory "stress" response with upregulation of pro-inflammatory cytokines and stimulation of the HPA axis (Gan et al., 1997). Cocaine abuse has also been associated with vascular pathology, including vasculitis, vasospasm and hemorrhage. These effects suggest that cocaine could perturb the function of endothelial cells, including the blood-brain barrier, and influence the progression to AIDS in HIV-infected individuals (Shapshak et al., 1997; Goodkin et al., 1997). In order to understand clinical consequences of cocaine abuse, it is important to gain insight into molecular and cellular basis of cocaine's effects on immune and endothelial cells. Cocaine's in vitro effects on (a) permeability, (b) immune cell migration, (c) adhesion molecules, and (d) cytokine expression were investigated in a blood-brain barrier model constructed with brain microvascular endothelial cells and fetal astrocytes with the following results: (a) cocaine and tumor necrosis factor-alpha (TNF-alpha) increased the model's permeability to inulin similarly in a dose-responsive fashion; (b) cocaine (10(-4) to 10(-8_ M) enhanced monocyte migration across the barrier with the maximum increase, approximately 100%, by 10(-5) M cocaine; (c) cocaine treatment also increased the expression of endothelial adhesion molecules, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecules-1 (VCAM-1) and platelet/endothelial cell adhesion molecule-1 (PECAM-1); (d) although the cocaine in vitro effects on cytokine production by mononuclear cells have been difficult to assess due to a heterogeneity in the degree of responsiveness between individuals, the data suggest that mononuclear cells from cocaine addicts are sensitized to in vitro cocaine challenge with hypersecretion of inflammatory cytokines. Cocaine's in vivo manifestations are compatible with these in vitro effects: (A) chronic cocaine treatment of rats significantly increased rolling white blood cell flux, leukocyte-endothelium adhesion, and ICAM-1 expression in the mesentery (House et al., 1996); (B) cocaine injection to cocaine-dependent subjects tipped the balance of cytokine secretion by mononuclear cells to Th1-type (Gan et al., 1997), and (C) cocaine injection stimulated the hypothalamic-pituitary axis (HPA) to increase both anti- and pro-inflammatory hormonal secretion. Collectively, these results suggest that the immune effects of cocaine on endothelial, immune and neuroendocrine cells impair the function of the blood-brain, barrier, increase cell emigration from the blood vessels, in particular into the brain, and may cause vasculitis. These effects could also increase importation of HIV-1 into the brain.


Assuntos
Adjuvantes Imunológicos/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Cocaína/farmacologia , Monócitos/efeitos dos fármacos , Complexo AIDS Demência/etiologia , Adesão Celular/efeitos dos fármacos , Moléculas de Adesão Celular/efeitos dos fármacos , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Transtornos Relacionados ao Uso de Cocaína/complicações , Transtornos Relacionados ao Uso de Cocaína/imunologia , Sistema Endócrino/efeitos dos fármacos , Sistema Endócrino/metabolismo , Humanos , Monócitos/fisiologia , Permeabilidade , Abuso de Substâncias por Via Intravenosa/imunologia , Vasculite/etiologia
15.
J Neurovirol ; 4(6): 619-26, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10065903

RESUMO

Cocaine abuse has been associated with vasculitis and stroke, and is suspected to influence the progression of AIDS dementia. Cocaine may enhance HIV-1 neuroinvasion by actions directed at the blood-brain barrier. HIV-1 appears to penetrate the human brain microvascular endothelial cell barrier by a paracellular route breached by tumor necrosis factor-alpha (TNF-alpha). Cocaine's effects on the blood-brain barrier were investigated using human brain microvascular endothelial cells and peripheral blood monocytes. Cocaine (10(-5) M and 10(-6) M) increased molecular permeability of the barrier and viral invasion by the macrophage-tropic HIV-1(JR-FL) into the brain chamber. Cocaine also augmented apoptosis of brain endothelial cells and monocytes, increased secretion of four chemokines (interleukin-8, interferon-inducible protein-10, macrophage inflammatory protein-1alpha, and monocyte chemoattractant protein-1) and the cytokine, TNF-alpha, by human monocytes. TNF-alpha enhanced invasion of the brain compartment by macrophage-tropic, lymphotropic, and bitropic HIV-1 strains. These data indicate that HIV-1 neuroinvasion can be increased by (a) cocaine's direct effects on brain microvascular endothelial cells and (b) paracrine effects of cocaine-induced pro-inflammatory cytokines and chemokines on the blood-brain barrier.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Cocaína/farmacologia , Infecções por HIV/imunologia , HIV-1 , Vasoconstritores/farmacologia , Apoptose/imunologia , Astrócitos/imunologia , Astrócitos/metabolismo , Astrócitos/virologia , Células Cultivadas , Quimiocina CCL4 , Endotélio Vascular/citologia , Endotélio Vascular/imunologia , Endotélio Vascular/virologia , Humanos , Proteínas Inflamatórias de Macrófagos/metabolismo , Macrófagos/imunologia , Macrófagos/virologia , Microcirculação , Monócitos/imunologia , Monócitos/virologia , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
16.
Cell Mol Life Sci ; 53(9): 750-8, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9368672

RESUMO

IgM antibodies directed against neuronal gangliosides GM1, GM2, GD1a, GD1b and GT1b occur in normal individuals and their level significantly decreases with age. Patients with lower motor neuron disease (LMND) produce high levels of these autoantibodies. AntiGM1 IgM is selectively augmented. In these patients, the CD5+ (B1) and CD5- (B2) subsets of B cells are not distinct entities but range from those without detectable CD5 marker to those with high CD5+ expression. B1 B cells were sorted to homogeneity, but B2 B cell cannot be isolated to homogeneity because of the presence of B1 cells with low CD5 expression. In short term cultures both the subsets produced IgM antibodies, but the antibodies reacted better with desialylated GM1 than with GM1. Cycloheximide (Cx) (0.35 mM) largely blocked IgM synthesis of the B1 B cells but inhibition of the B2 B cells was incomplete, possibly due to shedding of cytophilic antibodies as well as to the presence of B1 phenotype with loss of CD5 expression. CD5+ B cells may be involved in the production of antiglycolipid IgM.


Assuntos
Autoanticorpos/imunologia , Subpopulações de Linfócitos B/imunologia , Gangliosídeos/imunologia , Imunoglobulina M/imunologia , Doença dos Neurônios Motores/imunologia , Adulto , Idoso , Antígenos CD19/análise , Antígenos CD5/análise , Separação Celular , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios/imunologia
17.
Mol Med ; 3(8): 553-64, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9307983

RESUMO

BACKGROUND: HIV-1 invades the central nervous system early after infection when macrophage infiltration of the brain is low but myelin pallor is suggestive of blood-brain-barrier damage. High-level plasma viremia is a likely source of brain infection. To understand the invasion route, we investigated virus penetration across in vitro models with contrasting paracellular permeability subjected to TNF-alpha. MATERIALS AND METHODS: Blood-brain-barrier models constructed with human brain microvascular endothelial cells, fetal astrocytes, and collagen I or fibronectin matrix responded in a dose-related fashion to cytokines and ligands modulating paracellular permeability and cell migration. Virus penetration was measured by infectious and quantitative HIV-1 RNA assays. Barrier permeability was determined using inulin or dextran. RESULTS: Cell-free HIV-1 was retained by the blood-brain barrier with close to 100% efficiency. TNF-alpha increased virus penetration by a paracellular route in a dose-dependent manner proportionately to basal permeability. Brain endothelial cells were the main barrier to HIV-1. HIV-1 with monocytes attracted monocyte migration into the brain chamber. CONCLUSIONS: Early after the infection, the blood-brain barrier protects the brain from HIV-1. Immune mediators, such as TNF-alpha, open a paracellular route for the virus into the brain. The virus and viral proteins stimulate brain microglia and macrophages to attract monocytes into the brain. Infiltrating macrophages cause progression of HIV-1 encephalitis.


Assuntos
Barreira Hematoencefálica , HIV-1/patogenicidade , Fator de Necrose Tumoral alfa/farmacologia , Astrócitos , Bradicinina/análogos & derivados , Bradicinina/farmacologia , Técnicas de Cultura de Células , Permeabilidade da Membrana Celular , Movimento Celular , Células Cultivadas , Criança , Colágeno , Impedância Elétrica , Endotélio Vascular/citologia , Endotélio Vascular/virologia , Matriz Extracelular/virologia , Fibronectinas , Proteína do Núcleo p24 do HIV/metabolismo , Humanos , Interleucina-6/metabolismo , Monócitos/virologia , RNA Viral/análise
18.
Anal Biochem ; 247(2): 434-40, 1997 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-9177709

RESUMO

The success of recombinant interferon alpha in the clinic in part is limited by two properties of the protein: short serum half-life and immunogenicity. To improve these properties, interferon alpha-2a was conjugated with polyethylene glycol (PEG-5000). A homogeneous preparation of monopegylated interferon alpha-2a was subjected to vigorous analytical and activity characterization. A newly developed ampholyte-free chromatofocussing-like cation-exchange HPLC method utilizing a sulfopropyl resin was used to separate the monopegylated protein into 11 species. Peptide mapping, sequencing, and mass spectrometric analyses indicated that these species are positional isomers where each isomer represents a single polymer molecule conjugated to one specific lysine residue. No species with a modification at the amino terminus was observed. All 11 isomers show antiviral and antiproliferative activities in the same range as the parent monopegylated interferon alpha-2a.


Assuntos
Interferon-alfa/química , Polietilenoglicóis/química , Animais , Antivirais/química , Antivirais/isolamento & purificação , Antivirais/farmacologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia por Troca Iônica/métodos , Efeito Citopatogênico Viral/efeitos dos fármacos , Cães , Humanos , Interferon alfa-2 , Interferon-alfa/isolamento & purificação , Interferon-alfa/farmacologia , Isomerismo , Estrutura Molecular , Polietilenoglicóis/isolamento & purificação , Polietilenoglicóis/farmacologia , Proteínas Recombinantes
19.
J Neurol Sci ; 147(2): 201-2, 1997 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9106128

RESUMO

Guillain-Barré syndrome (GBS), an acute inflammatory polyradiculoneuropathy, is often associated with an antecedent factor, such as an infection, surgery, systemic malignancy, or vaccination. The first case of GBS following a vaccination with combined tetanus-diphtheria toxoid is reported.


Assuntos
Toxoide Diftérico/efeitos adversos , Polirradiculoneuropatia/induzido quimicamente , Toxoide Tetânico/efeitos adversos , Adulto , Toxoide Diftérico/imunologia , Humanos , Masculino , Polirradiculoneuropatia/etiologia , Polirradiculoneuropatia/imunologia
20.
Otolaryngol Head Neck Surg ; 116(4): 466-74, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9141396

RESUMO

In this study a new method of reinnervation for unilateral recurrent laryngeal nerve paralysis was performed in canines, producing physiologic vocal fold motion in each of a small series of animals. During the procedure the left anterior division of the recurrent laryngeal nerve was reinnervated with axons from the thyroarytenoid branch of the contralateral recurrent laryngeal nerve. The posterior branch of the left recurrent laryngeal nerve was divided and sutured to the ansa cervicalis to maintain tone in the posterior cricoarytenoid muscle. In all four animals, the right distal vocalis stump was reinnervated with an ansa cervicalis nerve branch. After 3 months physiologic vocal fold motion and electromyographic activity could be demonstrated during mechanical stimulation of the supraglottis (adduction) and during tracheostomy obstruction (abduction). Acoustic data revealed improvement of jitter, shimmer, signal-to-noise ratio, and vocal efficiency in reinnervated animals compared with paralyzed canines before treatment, although the results lacked statistical significance. This approach to the rehabilitation of unilateral vocal fold paralysis is discussed.


Assuntos
Nervo Laríngeo Recorrente/cirurgia , Paralisia das Pregas Vocais/cirurgia , Prega Vocal/fisiologia , Acústica , Anastomose Cirúrgica , Animais , Axônios , Plexo Cervical/cirurgia , Cães , Eletromiografia , Glote/fisiologia , Músculos Laríngeos/inervação , Laringoscopia , Movimento , Transferência de Nervo , Estimulação Física , Traqueostomia , Gravação em Vídeo , Vocalização Animal/fisiologia
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