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1.
J Immunol ; 201(11): 3229-3243, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30341184

RESUMO

Experimental autoimmune encephalomyelitis (EAE) in common marmosets is a translationally relevant model of the chronic neurologic disease multiple sclerosis. Following the introduction of a new dietary supplement in our purpose-bred marmoset colony, the percentage of marmosets in which clinically evident EAE could be induced by sensitization against recombinant human myelin oligodendrocyte glycoprotein in IFA decreased from 100 to 65%. The reduced EAE susceptibility after the dietary change coincided with reduced Callitrichine herpesvirus 3 expression in the colony, an EBV-related γ1-herpesvirus associated with EAE. We then investigated, in a controlled study in marmoset twins, which disease-relevant parameters were affected by the dietary change. The selected twins had been raised on the new diet for at least 12 mo prior to the study. In twin siblings reverted to the original diet 8 wk prior to EAE induction, 100% disease prevalence (eight out of eight) was restored, whereas in siblings remaining on the new diet the EAE prevalence was 75% (six out of eight). Spinal cord demyelination, a classical hallmark of the disease, was significantly lower in new-diet monkeys than in monkeys reverted to the original diet. In new-diet monkeys, the proinflammatory T cell response to recombinant human myelin oligodendrocyte glycoprotein was significantly reduced, and RNA-sequencing revealed reduced apoptosis and enhanced myelination in the brain. Systematic typing of the marmoset gut microbiota using 16S rRNA sequencing demonstrated a unique, Bifidobacteria-dominated composition, which changed after disease induction. In conclusion, targeted dietary intervention exerts positive effects on EAE-related parameters in multiple compartments of the marmoset's gut-immune-CNS axis.


Assuntos
Bifidobacterium/genética , Encéfalo/fisiologia , Células/imunologia , Suplementos Nutricionais , Encefalomielite Autoimune Experimental/dietoterapia , Esclerose Múltipla/dietoterapia , Medula Espinal/patologia , Animais , Apoptose , Callithrix , Células Cultivadas , Doenças Desmielinizantes , Dietoterapia , Modelos Animais de Doenças , Microbioma Gastrointestinal/genética , Herpesvirus Humano 3 , Humanos , Glicoproteína Mielina-Oligodendrócito/imunologia , RNA Ribossômico 16S/genética , Análise de Sequência de RNA
2.
Front Immunol ; 8: 804, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28744286

RESUMO

The absence of pathological hallmarks of progressive multiple sclerosis (MS) in commonly used rodent models of experimental autoimmune encephalomyelitis (EAE) hinders the development of adequate treatments for progressive disease. Work reviewed here shows that such hallmarks are present in the EAE model in marmoset monkeys (Callithrix jacchus). The minimal requirement for induction of progressive MS pathology is immunization with a synthetic peptide representing residues 34-56 from human myelin oligodendrocyte glycoprotein (MOG) formulated with a mineral oil [incomplete Freund's adjuvant (IFA)]. Pathological aspects include demyelination of cortical gray matter with microglia activation, oxidative stress, and redistribution of iron. When the peptide is formulated in complete Freund's adjuvant, which contains mycobacteria that relay strong activation signals to myeloid cells, oxidative damage pathways are strongly boosted leading to more intensive pathology. The proven absence of immune potentiating danger signals in the MOG34-56/IFA formulation implies that a narrow population of antigen-experienced T cells present in the monkey's immune repertoire is activated. This novel pathway involves the interplay of lymphocryptovirus-infected B cells with MHC class Ib/Caja-E restricted CD8+ CD56+ cytotoxic T lymphocytes.

3.
Proc Natl Acad Sci U S A ; 113(39): 10956-61, 2016 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-27621438

RESUMO

Narcolepsy with cataplexy is a rare and severe sleep disorder caused by the destruction of orexinergic neurons in the lateral hypothalamus. The genetic and environmental factors associated with narcolepsy, together with serologic data, collectively point to an autoimmune origin. The current animal models of narcolepsy, based on either disruption of the orexinergic neurotransmission or neurons, do not allow study of the potential autoimmune etiology. Here, we sought to generate a mouse model that allows deciphering of the immune mechanisms leading to orexin(+) neuron loss and narcolepsy development. We generated mice expressing the hemagglutinin (HA) as a "neo-self-antigen" specifically in hypothalamic orexin(+) neurons (called Orex-HA), which were transferred with effector neo-self-antigen-specific T cells to assess whether an autoimmune process could be at play in narcolepsy. Given the tight association of narcolepsy with the human leukocyte antigen (HLA) HLA-DQB1*06:02 allele, we first tested the pathogenic contribution of CD4 Th1 cells. Although these T cells readily infiltrated the hypothalamus and triggered local inflammation, they did not elicit the loss of orexin(+) neurons or clinical manifestations of narcolepsy. In contrast, the transfer of cytotoxic CD8 T cells (CTLs) led to both T-cell infiltration and specific destruction of orexin(+) neurons. This phenotype was further aggravated upon repeated injections of CTLs. In situ, CTLs interacted directly with MHC class I-expressing orexin(+) neurons, resulting in cytolytic granule polarization toward neurons. Finally, drastic neuronal loss caused manifestations mimicking human narcolepsy, such as cataplexy and sleep attacks. This work demonstrates the potential role of CTLs as final effectors of the immunopathological process in narcolepsy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Citotoxicidade Imunológica , Narcolepsia/imunologia , Narcolepsia/patologia , Neurônios/patologia , Orexinas/metabolismo , Animais , Autoanticorpos/metabolismo , Autoantígenos/metabolismo , Comunicação Celular , Hemaglutininas/metabolismo , Hipotálamo/metabolismo , Inflamação/patologia , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Fenótipo , Linfócitos T Citotóxicos/metabolismo , Células Th1/metabolismo
4.
J Electron Imaging ; 23(1): 013013, 2014 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-24860245

RESUMO

We investigate the use of different trabecular bone descriptors and advanced machine learning tech niques to complement standard bone mineral density (BMD) measures derived from dual-energy x-ray absorptiometry (DXA) for improving clinical assessment of osteoporotic fracture risk. For this purpose, volumes of interest were extracted from the head, neck, and trochanter of 146 ex vivo proximal femur specimens on multidetector computer tomography. The trabecular bone captured was characterized with (1) statistical moments of the BMD distribution, (2) geometrical features derived from the scaling index method (SIM), and (3) morphometric parameters, such as bone fraction, trabecular thickness, etc. Feature sets comprising DXA BMD and such supplemental features were used to predict the failure load (FL) of the specimens, previously determined through biomechanical testing, with multiregression and support vector regression. Prediction performance was measured by the root mean square error (RMSE); correlation with measured FL was evaluated using the coefficient of determination R2. The best prediction performance was achieved by a combination of DXA BMD and SIM-derived geometric features derived from the femoral head (RMSE: 0.869 ± 0.121, R2: 0.68 ± 0.079), which was significantly better than DXA BMD alone (RMSE: 0.948 ± 0.119, R2: 0.61 ± 0.101) (p < 10-4). For multivariate feature sets, SVR outperformed multiregression (p < 0.05). These results suggest that supplementing standard DXA BMD measurements with sophisticated femoral trabecular bone characterization and supervised learning techniques can significantly improve biomechanical strength prediction in proximal femur specimens.

5.
JAMA Neurol ; 70(10): 1305-10, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23939463

RESUMO

IMPORTANCE: Idiopathic narcolepsy with cataplexy is thought to be an autoimmune disorder targeting hypothalamic hypocretin neurons. Symptomatic narcolepsy with low hypocretin level has been described in Ma antibody­associated encephalitis; however, the mechanisms underlying such an association remain unknown. OBSERVATIONS: We described a 63-year-old man with clinical criteria for diencephalic encephalitis with sleepiness, cataplexy, hypocretin deficiency, and central hypothyroidism, together with brainstem encephalitis reflected by supranuclear ophtalmoparesis and rapid eye movement sleep behavior disorder with underlying abnormalities on brain magnetic resonance imaging. An autoimmune process was demonstrated by the detection of antibodies against Ma protein. Death occurred 4 months after disease onset without any tumor detected. Neuropathology, immunohistochemistry, and immunoreactivity results were compared with those obtained in idiopathic narcolepsy-cataplexy and with normal control brains. The principal findings revealed almost exclusive inflammation and tissue injury in the hypothalamus. The type of inflammatory reaction suggests cytotoxic CD8+ T lymphocytes being responsible for the induction of tissue injury. Inflammation was associated with complete loss of hypocretinergic neurons. Autoantibodies of the patient predominantly stained neurons in the hypothalamus and could be absorbed with Ma2. CONCLUSIONS AND RELEVANCE: The encephalitic process, responsible for narcolepsy-cataplexy and hypocretin deficiency, reflects a CD8+ inflammatory-mediated response against hypocretin neurons.


Assuntos
Encefalite Viral , Antígenos HIV/imunologia , Hipotálamo/metabolismo , Narcolepsia/complicações , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia , Antígenos CD/metabolismo , Aquaporina 4/metabolismo , Autoanticorpos/sangue , Autoanticorpos/líquido cefalorraquidiano , Encefalite Viral/complicações , Encefalite Viral/imunologia , Encefalite Viral/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuropeptídeos/metabolismo , Orexinas , Terceiro Ventrículo/patologia
6.
J Neuropathol Exp Neurol ; 70(11): 992-1005, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22002426

RESUMO

This study investigated the effect of CD20-positive B-cell depletion on central nervous system (CNS) white and gray matter pathology in experimental autoimmune encephalomyelitis in common marmosets, a relevant preclinical model of multiple sclerosis. Experimental autoimmune encephalomyelitis was induced in 14 marmosets by immunization with recombinant human myelin oligodendrocyte glycoprotein in complete Freund adjuvant. At 21 days after immunization, B-cell depletion was achieved by weekly intravenous injections of HuMab 7D8, a human-anti-human CD20 antibody that cross-reacts with marmoset CD20. In vivo magnetic resonance imaging showed widespread brain white matter demyelination in control marmosets that was absent in CD20 antibody-treated marmosets. High-contrast postmortem magnetic resonance imaging showed white matter lesions in 4of the 7 antibody-treated marmosets, but these were significantly smaller than those in controls. The same technique revealed gray matter lesions in 5 control marmosets, but none in antibody-treated marmosets. Histologic analysis confirmed that inflammation, demyelination, and axonal damage were substantially reduced in brain, spinal cord, and optic nerves of CD20 antibody-treated marmosets. In conclusion, CD20-postive B-cell depletion by HuMab 7D8 profoundly reduced the development of both white and gray matter lesions in the marmoset CNS. These data underline the central role of B cells in CNS inflammatory-demyelinating disease.


Assuntos
Anticorpos/uso terapêutico , Linfócitos B/patologia , Encéfalo/patologia , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/patologia , Fibras Nervosas Mielinizadas/patologia , Animais , Antígenos CD20/imunologia , Antígenos CD20/metabolismo , Linfócitos B/efeitos dos fármacos , Encéfalo/metabolismo , Calgranulina B/metabolismo , Callithrix , Complemento C9/metabolismo , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/induzido quimicamente , Adjuvante de Freund/efeitos adversos , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Imageamento por Ressonância Magnética , Proteínas da Mielina/efeitos adversos , Proteína Proteolipídica de Mielina/metabolismo , Glicoproteína Mielina-Oligodendrócito , Proteínas de Neurofilamentos/metabolismo , Estatísticas não Paramétricas , Tetraspanina 29/metabolismo
7.
J Neuropathol Exp Neurol ; 69(4): 372-85, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20448482

RESUMO

Experimental autoimmune encephalomyelitis in the neotropical primate common marmoset (Callithrix jacchus) is a relevant autoimmune animal model of multiple sclerosis. T cells specific for peptide 34 to 56 of myelin/oligodendrocyte glycoprotein (MOG34-56) have a central pathogenic role in this model. The aim of this study was to assess the requirement for innate immune stimulation for activation of this core pathogenic autoimmune mechanism. Marmoset monkeys were sensitized against synthetic MOG34-56 peptide alone or in combination with the nonencephalitogenic peptide MOG74-96 formulated in incomplete Freund adjuvant, which lacks microbial components. Experimental autoimmune encephalomyelitis development was recorded by monitoring neurological signs, brain magnetic resonance imaging, and longitudinal profiling of cellular and humoral immune parameters. All monkeys developed autoimmune inflammatory/demyelinating central nervous system disease characterized by massive brain and spinal cord demyelinating white matter lesions with activated macrophages and CD3+ T cells. Immune profiling ex vivo demonstrated the activation of mainly CD3+CD4+/8+CD56+ T cells against MOG34-56. Upon ex vivo stimulation, these T cells produced more interleukin 17A compared with TH1 cytokines (e.g. interferon-gamma) and displayed peptide-specific cytolytic activity. These results indicate that the full spectrum of marmoset experimental autoimmune encephalomyelitis can be induced by sensitization against a single MOG peptide in incomplete Freund adjuvant lacking microbial compounds for innate immune activation and by eliciting antigen-specific T-cell cytolytic activity.


Assuntos
Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/induzido quimicamente , Modelos Animais de Doenças , Adjuvante de Freund/química , Glicoproteínas/farmacologia , Fragmentos de Peptídeos/farmacologia , Animais , Antígenos CD/metabolismo , Autoanticorpos/sangue , Autoanticorpos/imunologia , Encéfalo/imunologia , Encéfalo/patologia , Calgranulina B/metabolismo , Callithrix , Linhagem Celular Transformada , Citocinas/metabolismo , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/imunologia , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/patologia , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/fisiopatologia , Citometria de Fluxo/métodos , Humanos , Imunidade Inata , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Imageamento por Ressonância Magnética/métodos , Proteína Proteolipídica de Mielina/metabolismo , Glicoproteína Mielina-Oligodendrócito , Medula Espinal/patologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo
8.
Dis Colon Rectum ; 52(1): 112-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19273965

RESUMO

PURPOSE: Fecal incontinence is a serious complication after repair of anorectal malformations. We investigated whether reoperation can improve fecal continence. METHODS: Medical records of 41 patients (40 children and one adult; 26 male and 15 female) who underwent reoperation after previous reconstruction of an anorectal malformation were reviewed for outcomes of bowel function. Type of primary corrective surgery performed, therapeutic measures, results of physical examination and barium enema, and reoperation procedures were evaluated. A questionnaire was administered to assess stool behaviour and level of continence at follow-up three or more years after secondary operation. RESULTS: Secondary operations in males comprised posterior sagittal anorectoplasty (PSARP) in 16 patients, PSARP with antegrade continent enema in one patient, antegrade continent enema alone in 6, anoplasty in one, rectosigmoid resection in 1, and definitive colostomy in 1 patient. Secondary operations in females included PSARP alone in 4 patients, PSARP with total urogenital mobilization in 4, PSARP with vaginoplasty in 2, PSARP with vaginoplasty and antegrade continent enema in 2, and PSARP with vaginourethroplasty in 3. Of 41 patients 18 (44 percent) were continent at follow-up, 21 (51 percent) were clean with use of enemas, diet, or drug therapy. One patient had a definitive colostomy. One died after kidney transplantation. CONCLUSIONS: Surgery is a good option for improving incontinence in selected patients previously operated for anorectal malformations. Posterior sagittal anorectoplasty is advocated to improve bowel control. Antegrade continent enema is a reliable therapeutic option to maintain clean patients with fecal incontinence.


Assuntos
Canal Anal/anormalidades , Incontinência Fecal/cirurgia , Reto/anormalidades , Canal Anal/cirurgia , Criança , Pré-Escolar , Incontinência Fecal/etiologia , Incontinência Fecal/fisiopatologia , Feminino , Humanos , Masculino , Complicações Pós-Operatórias , Reto/cirurgia , Reoperação , Sistema Urinário/anormalidades , Sistema Urinário/cirurgia
9.
Forsch Komplementmed ; 13(4): 241-3, 2006 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-16980772

RESUMO

Clinical case of an 18-day-old newborn of the 40th + 1 pregnancy week with postpartum respiratory adjustment disorder including periodical decreases in blood oxygen saturation. On day 8 postpartum the newborn developed myoclonic cramps of unknown origin combatted with phenobarbital. 6 days later Cheyne-Stokes breathing began under normal phenobarbital level being the cause for an additional homeopathic therapy trial. After a single dose of opium C 30 the breathing improved significantly, suspending the breaks in breathing and the decreases in blood oxygen saturation.


Assuntos
Apneia/terapia , Respiração de Cheyne-Stokes/terapia , Homeopatia/métodos , Ópio/uso terapêutico , Oxigênio/sangue , Fenobarbital/uso terapêutico , Apneia/etiologia , Respiração de Cheyne-Stokes/etiologia , Eletroencefalografia , Humanos , Recém-Nascido , Masculino , Consumo de Oxigênio , Resultado do Tratamento
10.
J Immunol ; 175(7): 4761-8, 2005 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16177124

RESUMO

IL-12p40 is a shared subunit of two cytokines with overlapping activities in the induction of autoreactive Th1 cells and therefore a potential target of therapy in Th1-mediated diseases. We have examined whether ongoing disease in a nonhuman primate model of multiple sclerosis (MS) can be suppressed with a new human IgG1kappa Ab against human IL-12p40. Lesions developing in the brain white matter were visualized and characterized with standard magnetic resonance imaging techniques. To reflect the treatment of MS patients, treatment with the Ab was initiated after active brain white matter lesions were detected in T2-weighted images. In placebo-treated control monkeys we observed the expected progressive increase in the total T2 lesion volume and markedly increased T2 relaxation times, a magnetic resonance imaging marker of inflammation. In contrast, in monkeys treated with anti-IL-12p40 Ab, changes in the total T2 lesion volume and T2 relaxation times were significantly suppressed. Moreover, the time interval to serious neurological deficit was delayed from 31 +/- 10 to 64 +/- 20 days (odds ratio, 0.312). These results, in a disease model with high similarity to MS, are important for ongoing and planned trials of therapies that target IL-12 and/or IL-23.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Callithrix , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/prevenção & controle , Interleucina-12/imunologia , Subunidades Proteicas/imunologia , Animais , Anticorpos Monoclonais/uso terapêutico , Encéfalo/patologia , Modelos Animais de Doenças , Progressão da Doença , Avaliação Pré-Clínica de Medicamentos , Encefalomielite Autoimune Experimental/diagnóstico , Encefalomielite Autoimune Experimental/patologia , Humanos , Subunidade p40 da Interleucina-12 , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Esclerose Múltipla/prevenção & controle
11.
J Comput Assist Tomogr ; 29(2): 246-53, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15772547

RESUMO

PURPOSE: To compare multislice computed tomography (MSCT)-derived parameters of the trabecular bone structure of the calcaneus with bone mineral density (BMD) in their ability to differentiate between donors with and without osteoporotic fractures of the spine and to optimize CT scan protocols. METHODS: Forty-two postmortem calcanei (81.2 +/- 10 years) were imaged with a 16-detector row MSCT system using 4 different scan protocols varying spatial resolution (12-24 lp/cm) and radiation dose. Structural parameters of trabecular bone were derived from these images, and BMDs of the calcanei were determined using dual x-ray absorptiometry. Vertebral deformities of the spine were radiographically classified using the Spinal Fracture Index. Diagnostic performance in differentiation between donors with and without vertebral fractures was assessed using receiver operating characteristic (ROC) analysis. RESULTS: There were significant case-control differences for many of the structural parameters measured (P < 0.05). The highest ROC values were found for apparent trabecular thickness using the high-resolution and high-dose protocols. Statistically significant correlations were found between most structure parameters and BMD (up to r = 0.85, P < 0.01). CONCLUSION: Structural parameters of trabecular bone as obtained from high-resolution MSCT images of the calcaneus can be used to differentiate between donors with and without osteoporotic vertebral fractures, using a high-resolution and high-dose CT protocol.


Assuntos
Densidade Óssea/fisiologia , Calcâneo/diagnóstico por imagem , Fraturas Espontâneas/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Osteoporose/diagnóstico por imagem , Fraturas da Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada Espiral , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Calibragem , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Imagens de Fantasmas , Valor Preditivo dos Testes , Valores de Referência
12.
Bioresour Technol ; 85(3): 243-8, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12365490

RESUMO

A fixed-film (biofilm) reactor was designed and its performance was determined at various retention times. The goal was to find the optimal retention time for recycling plant nutrients in an advanced life support system, to minimize the size, mass, and volume (hold-up) of a production model. The prototype reactor was tested with aqueous leachate from wheat crop residue at 24, 12, 6, and 3 h hydraulic retention times (HRTs). Biochemical oxygen demand (BOD), nitrates and other plant nutrients, carbohydrates, total phenolics, and microbial counts were monitored to characterize reactor performance. BOD removal decreased significantly from 92% at the 24 h HRT to 73% at 3 h. Removal of phenolics was 62% at the 24 h retention time, but 37% at 3 h. Dissolved oxygen concentrations, nitric acid consumption, and calcium and magnesium removals were also affected by HRT. Carbohydrate removals, carbon dioxide (CO2) productions, denitrification, potassium concentrations, and microbial counts were not affected by different retention times. A 6 h HRT will be used in future studies to determine the suitability of the bioreactor effluent for hydroponic plant production.


Assuntos
Bactérias Aeróbias/metabolismo , Biofilmes , Reatores Biológicos , Oxigênio/metabolismo , Eliminação de Resíduos/instrumentação , Eliminação de Resíduos/métodos , Reologia/métodos , Bactérias Aeróbias/crescimento & desenvolvimento , Biodegradação Ambiental , Metabolismo dos Carboidratos , Dióxido de Carbono , Produtos Agrícolas/metabolismo , Estudos de Viabilidade , Hidroponia/instrumentação , Hidroponia/métodos , Compostos Inorgânicos/metabolismo , Minerais/metabolismo , Compostos Orgânicos/metabolismo , Potássio/metabolismo , Controle de Qualidade , Reologia/instrumentação , Triticum/metabolismo
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