Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Lupus ; 33(9): 901-909, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38722195

RESUMO

OBJECTIVES: This study investigated the clinically relevant factors for headaches in patients with systemic lupus erythematosus (SLE) using a registry from a Japanese multicenter cohort. METHODS: This cross-sectional study analysed the clinical information of patients with SLE who experienced headache episodes using the Migraine Disability Assessment (MIDAS) questionnaire. Significant findings in the comparisons between patients with headache (HA patients) and those without headache (non-HA patients) and in the comparisons depending on the grades of headache-induced disability in daily life based on the MIDAS scores were evaluated. Multivariate logistic regression analyses were performed to identify the relevant factors for headache. RESULTS: We analyzed 369 patients (median age, 45 years; female, 90.8%), including 113 HA patients who were significantly younger than non-HA patients (p < .005). HA patients had significantly higher frequencies of photosensitivity, rashes, and mucosal ulcers than non-HA patients (p < .05). Age and photosensitivity were significantly associated with headache (odds ratio (OR) 0.93, 95% confidence interval (CI) 0.95-0.99; OR 2.11, 95% CI 1.29-3.49, respectively). In the HA patients, hypocomplementemia was significantly associated with a disability of more than mild grade (OR 2.89, 95% CI 1.14-7.74), while rash was significantly observed in those presenting with moderate and severe disability. CONCLUSION: This study suggests that photosensitivity is a relevant manifestation of headache in patients with SLE. Persistent hypocomplementemia can contribute to headache-induced disability in daily life, whereas a rash may be a dominant manifestation in patients presenting with moderate/severe headache-induced disability.


Assuntos
Cefaleia , Lúpus Eritematoso Sistêmico , Sistema de Registros , Humanos , Feminino , Estudos Transversais , Pessoa de Meia-Idade , Masculino , Adulto , Lúpus Eritematoso Sistêmico/complicações , Japão/epidemiologia , Cefaleia/etiologia , Cefaleia/epidemiologia , Inquéritos e Questionários , Modelos Logísticos , Avaliação da Deficiência , Índice de Gravidade de Doença , Análise Multivariada , Fatores Etários , Transtornos de Fotossensibilidade/epidemiologia , Transtornos de Fotossensibilidade/etiologia , Idoso
2.
Clin Exp Immunol ; 213(1): 125-137, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-36794867

RESUMO

To investigate the features of circulating B cells, their expressing receptors, serum levels of B-cell activation factor of the TNF family (BAFF), and a proliferation-inducing ligand (APRIL) in antineutrophil cytoplasmic antibody-associated vasculitis (AAV). Blood samples from 24 patients with active AAV (a-AAV), 13 with inactive AAV (i-AAV), and 19 healthy controls (HC) were included in this study. The proportion of B cells and their expressing BAFF receptor (BAFF-R), transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI), and B-cell maturation antigen were analyzed via flow cytometry. Serum levels of BAFF, APRIL, and interleukin (IL)-4, IL-6, IL-10, and IL-13 were also evaluated using an enzyme-linked immunosorbent assay. The proportion of plasmablasts (PB)/plasma cells (PC) and serum levels of BAFF, APRIL, IL-4, and IL-6 were significantly higher in a-AAV than in HC. Higher serum levels of BAFF, APRIL, and IL-4 were observed in i-AAV than in HC. Lower expression of BAFF-R on memory B cells and higher expression of TACI on CD19+ cells, immature B cells, and PB/PC were demonstrated in a-AAV and i-AAV than in HC. The population of memory B cells was positively associated with serum APRIL levels and BAFF-R expression in a-AAV. In conclusion, decreased expression of BAFF-R on memory B cells and increased expression of TACI on CD19+ cells, immature B cells, and PB/PC, as well as increased serum levels of BAFF and APRIL, were sustained even in the remission phase of AAV. Persistent aberrant signaling of BAFF/APRIL may contribute to disease relapse.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Interleucina-4 , Humanos , Anticorpos Anticitoplasma de Neutrófilos , Interleucina-6 , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Fator Ativador de Células B , Receptor do Fator Ativador de Células B
3.
Clin Exp Immunol ; 206(2): 184-195, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34319596

RESUMO

We investigated the characteristics of regulatory T cells in adult-onset Still's disease (AOSD) with a focus on their plasticity, stability and relationship to disease severity. The proportion of circulating CD4+ CD25+ forkhead box protein 3 (FoxP3+ ) cells (Tregs ) and intracellular expression of effector cytokines, including interferon (IFN)-γ, interleukin (IL)-17 and IL-4, was analysed in 27 untreated patients with AOSD (acute AOSD), 11 of the 27 patients after remission and 16 healthy controls (HC) using flow cytometry. The suppressive ability of Tregs was also evaluated. Regression analyses of the results were performed. The proportion of Tregs was significantly lower in patients with acute AOSD than in the HC. The expression levels of IFN-γ, IL-17 and IL-4 in Tregs were significantly increased in patients with acute AOSD. IFN-γ and IL-4 expression levels were inversely correlated with the proportion of Tregs and positively correlated with serum ferritin levels. Decreased expression of FoxP3 in CD4+ CD25+ cells, which was correlated with increased expression of IL-17, and impaired suppressive function were observed in Tregs in acute AOSD. However, these aberrant findings in Tregs , including the reduced circulating proportion and functional ability and altered intracellular expression levels of cytokines and FoxP3, were significantly improved after remission. In acute AOSD, Tregs show plastic changes, including effector cytokine production and reductions in their proportion and functional activity. IFN-γ and IL-4 expression levels in Tregs may be associated with disease severity. Also, down-regulation of FoxP3 may be related to IL-17 expression in Tregs . Importantly, the stability of Tregs can be restored in remission.


Assuntos
Citocinas/imunologia , Regulação da Expressão Gênica/imunologia , Doença de Still de Início Tardio/imunologia , Linfócitos T Reguladores/imunologia , Doença Aguda , Citocinas/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Doença de Still de Início Tardio/sangue , Doença de Still de Início Tardio/terapia , Linfócitos T Reguladores/metabolismo
4.
J Stroke Cerebrovasc Dis ; 26(9): e177-e179, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28733124

RESUMO

Cerebral embolism is typically caused by a cardiogenic thrombus. The patent foramen ovale is a well-known cause of paradoxical embolism. However, some idiopathic cases of stroke have been reported. Such strokes are designated as embolic stroke of undetermined sources. Among them, lung lobectomy may be a new embolic risk factor for cerebral embolism. The risk of thrombus formation is high at the pulmonary vein stump after lung lobectomy, especially in the left upper lobe. Interestingly, the risk remains several years after surgery. This condition is mostly overlooked, and reported cases of this condition are rare. Methods of early detection, prevention, and treatment have not been established. Here we report the case of a 66-year-old man who suffered a cerebral infarction 2 days after left upper lobectomy. Three-dimensional computed tomography scan clearly revealed the structural feature of the pulmonary vein stump. The stump of patients with cerebral infarction after lung lobectomy should be checked.


Assuntos
Adenocarcinoma/cirurgia , Infarto Cerebral/etiologia , Embolia Intracraniana/etiologia , Neoplasias Pulmonares/cirurgia , Pneumonectomia/efeitos adversos , Veias Pulmonares/cirurgia , Trombose Venosa/etiologia , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Idoso , Angiografia Cerebral/métodos , Infarto Cerebral/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Imagem de Difusão por Ressonância Magnética , Humanos , Embolia Intracraniana/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Angiografia por Ressonância Magnética , Masculino , Flebografia/métodos , Veias Pulmonares/diagnóstico por imagem , Fatores de Risco , Trombose Venosa/diagnóstico por imagem
5.
Immunol Res ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958876

RESUMO

We investigated the phenotypic characteristics of human leukocyte antigen (HLA)-E-expressing macrophages, NKG2A/CD94 expression in T and natural killer (NK) cells, and their interactions in patients with adult-onset Still's disease (AOSD). Peripheral blood mononuclear cells from 22 patients with AOSD and 22 healthy controls (HC) were used. Isolated monocytes were cultured first with macrophage colony-stimulating factor to differentiate into M0 macrophages and subsequently with lipopolysaccharide/interferon-γ or interleukin-4 to differentiate into M1 or M2 macrophages, respectively. HLA-E and NKG2A/CD94 expression levels were evaluated using quantitative RT-PCR and flow cytometry. HLA-E expression in M0 and M2 macrophages was significantly higher in patients with AOSD than in HC, and was positively correlated with serum C-reactive protein levels and erythrocyte sedimentation rate. NKG2A/CD94 expression in CD4 + and CD8 + T cells was significantly higher in patients with AOSD than in HC, but that in NK cells was not significantly different. In patients with AOSD, NKG2A expression in CD4 + T cells positively correlated with HLA-E expression in M0, M1, and M2 macrophages. CD94 expression in CD8 + T cells inversely correlated with HLA-E expression in M1 and M2 macrophages. NKG2A and CD94 expression in NK cells inversely correlated with HLA-E expression in M0, M1, and M2 macrophages. No significant correlation was observed between HLA-E and NKG2A/CD94 expression in HC. Increased expression of HLA-E in macrophages and NKG2A/CD94 in T cells can be observed in the inflammatory condition of AOSD. HLA-E-expressing macrophages may be associated with NKG2A/CD94 expression in T and NK cells with different correlations.

6.
Autoimmun Rev ; 23(7-8): 103602, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39153646

RESUMO

Skeletal muscle involvement is common in patients with small- and medium-sized vasculitis, particularly polyarteritis nodosa (PAN) and antineutrophil cytoplasmic antibody-associated vasculitis (AAV). Despite being not included in the standard classification criteria for PAN and AAV, skeletal muscle involvement is an important clinical indicator, particularly when vasculitic myopathy is the only pathological evidence in the absence of other organ involvement. Herein, we comprehensively reviewed and compared the clinical features of 71 and 135 patients with PAN and AAV, respectively, with skeletal muscle involvement at the time of disease onset. Most patients with PAN and AAV exhibited skeletal muscle involvement, often characterized by myalgia and occasional muscular weakness, predominantly in the lower extremities. Myalgia and weakness were observed more frequently in the distal lower extremities in patients with PAN than in those with AAV. In contrast, skeletal muscle involvement tended to exhibit a more dispersed distribution across all four extremities in those with AAV. Muscle magnetic resonance imaging T2-weighted and short-tau inversion recovery sequences can effectively identify hyperintense areas attributed to hypervascularity of affected muscle tissues and serve as a sensitive and useful modality for visually determining the suitable biopsy site. >90% of patients with PAN and AAV demonstrated perivascular inflammation in their affected muscle tissues, whereas fibrinoid necrosis of the vessel walls was reported in two-thirds of patients. Serum creatine kinase (CK) levels were within the normal range in approximately 80% of patients presenting with skeletal muscle involvement in PAN and AAV. Furthermore, muscle fiber damage was milder in patients with skeletal muscle involvement in PAN and AAV than those with idiopathic inflammatory myositis. Meanwhile, serum CK levels were elevated in 65-85% of patients with PAN and AAV who had myofiber necrosis and degeneration in the affected muscles. Most patients with PAN and AAV showed improvement in skeletal muscle involvement following glucocorticoids (GCs) administration; however, relapse was observed in some patients during the tapering of GCs. In summary, skeletal muscle involvement is a potential indicator for establishing PAN and AAV diagnoses during the early phases of the disease.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Músculo Esquelético , Poliarterite Nodosa , Humanos , Poliarterite Nodosa/diagnóstico , Poliarterite Nodosa/complicações , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Músculo Esquelético/patologia
7.
Adv Rheumatol ; 62(1): 49, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36575548

RESUMO

BACKGROUND: Some patients have normal levels of complement during the diagnosis of systemic lupus erythematosus (SLE), although decreased serum levels of complement are a hallmark of the active phase of the disease. This study investigated the clinical characteristics, impact on the classification of SLE, and the prognosis of patients with SLE who had normal serum complement levels at initial diagnosis (N-com). METHODS: We evaluated 21 patients with N-com and 96 patients with hypocomplementemia at the initial diagnosis of SLE (H-com). The classification rates among the American College of Rheumatology (ACR) 1997, Systemic Lupus International Collaborating Clinics (SLICC) 2012, European League Against Rheumatism (EULAR)/ACR 2019 criteria, and clinical and immunological involvements were compared between SLE patients with N-com and H-com. Relapse and organ damage based on the SLICC/ACR damage index were also evaluated. RESULTS: The classification rates of SLE were not significantly different in the ACR, SLICC, and EULAR/ACR criteria between the N-com and H-com groups. Patients with N-com had no significant differences in the classification rates among the three criteria, whereas patients with H-com had lower classification rates in the ACR criteria than in the SLICC criteria. A lower incidence of renal manifestation, less positivity for anti-dsDNA antibody, and a higher incidence of fever were observed in patients with N-com than in those with H-com. The occurrence of relapse and organ damage was not significantly different between patients with N-com and H-com. CONCLUSION: Patients with N-com were less involved in renal manifestation and anti-dsDNA antibody positivity but had a higher incidence of fever than those with H-com, while having no disadvantage in SLE classification processes. Serum complement levels at the initial diagnosis of SLE may not predict prognosis.


Assuntos
Lúpus Eritematoso Sistêmico , Doenças Reumáticas , Reumatologia , Humanos , Estados Unidos , Rim , Recidiva
8.
Sci Rep ; 12(1): 6787, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35474094

RESUMO

Adult-onset Still's disease (AOSD)-a systemic inflammatory disease-often occurs at a young age. Recently, elderly onset patient proportion has been increasing; however, data are limited. To evaluate the characteristics of elderly patients with AOSD in a multicenter cohort, we retrospectively analyzed 62 patients with AOSD at five hospitals during April 2008-December 2020. Patients were divided into two groups according to age at disease onset: younger-onset (≤ 64 years) and elderly onset (≥ 65 years). Clinical symptoms, complications, laboratory findings, treatment, and outcomes were compared. Twenty-six (41.9%) patients developed AOSD at age ≥ 65 years. The elderly onset group had a lower frequency of sore throat (53.8% vs. 86.1%), higher frequency of pleuritis (46.2% vs. 16.7%), and higher complication rates of disseminated intravascular coagulation (30.8% vs. 8.3%) and macrophage activation syndrome (19.2% vs. 2.8%) than the younger onset group. Cytomegalovirus infections were frequent in elderly onset patients (38.5% vs. 13.9%) but decreased with early glucocorticoid dose reduction and increased immunosuppressant and tocilizumab use. Elderly AOSD is not uncommon; these patients have different characteristics than younger-onset patients. Devising a way to control disease activity quickly while managing infections may be an important goal in elderly AOSD.


Assuntos
Infecções por Citomegalovirus , Síndrome de Ativação Macrofágica , Doença de Still de Início Tardio , Adulto , Idoso , Infecções por Citomegalovirus/complicações , Humanos , Imunossupressores/uso terapêutico , Síndrome de Ativação Macrofágica/complicações , Síndrome de Ativação Macrofágica/tratamento farmacológico , Estudos Retrospectivos , Doença de Still de Início Tardio/complicações , Doença de Still de Início Tardio/tratamento farmacológico , Doença de Still de Início Tardio/epidemiologia
9.
Front Immunol ; 12: 789740, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34950150

RESUMO

We investigated the characteristics of regulatory T cells (Tregs), focusing on the relationship between their stability and reactive oxygen species (ROS), in antineutrophil cytoplasmic antibody-associated vasculitis (AAV). Intracellular expressions of effector cytokines, forkhead box protein 3 (FoxP3), ROS, phosphorylated mammalian target of rapamycin (mTOR), and sirtuin 1 (SIRT1) in Tregs from peripheral blood mononuclear cells (PBMCs) of patients with AAV and healthy controls (HC) were analyzed. The alterations in and functional ability of Tregs were compared before and after resveratrol (RVL) treatment of PBMCs in patients with AAV. Significantly higher expressions of interferon (IFN)-γ, interleukin (IL)-17, IL-4, ROS, and phosphorylated mTOR (pho-mTOR) and lower expression of SIRT1 in CD4+CD25+FoxP3+ cells were found in patients with AAV than in the HC. FoxP3 expression in CD4+CD25+ cells and suppressive function of Tregs were significantly lower in patients with AAV than in the HC. Tregs after RVL treatment demonstrated significant decreases in IFN-γ, ROS, and pho-mTOR levels and increases in FoxP3, SIRT1 levels, and functional activity. Conversely, the direct activation of SIRT1 by SRT1720 resulted in decreased FoxP3 expression, with no reduction in ROS levels. The pho-mTOR levels were significantly higher in Tregs after activation by SRT1720 than in those after RVL treatment. This study suggested that imbalanced changes in Tregs could be attributed to mTOR activation, in which ROS overproduction was predominantly implicated. Therefore, ROS is a key mediator for promoting Tregs instability in AAV.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/sangue , Granulomatose com Poliangiite/metabolismo , Poliangiite Microscópica/metabolismo , Estresse Oxidativo , Linfócitos T Reguladores/metabolismo , Antioxidantes/farmacologia , Estudos de Casos e Controles , Células Cultivadas , Citocinas/metabolismo , Feminino , Fatores de Transcrição Forkhead/metabolismo , Granulomatose com Poliangiite/sangue , Granulomatose com Poliangiite/imunologia , Humanos , Masculino , Poliangiite Microscópica/sangue , Poliangiite Microscópica/imunologia , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Fenótipo , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Resveratrol/farmacologia , Transdução de Sinais , Sirtuína 1/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Serina-Treonina Quinases TOR/metabolismo
10.
Case Rep Rheumatol ; 2020: 8897358, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33014504

RESUMO

Articular symptoms are commonly present in polyarteritis nodosa (PAN). Meanwhile, they may occur as the initial and main involvement of PAN, raising a concern of a delay in a definitive diagnosis of disease unless the histological evidence is obtained. Herein, we report two cases of cutaneous PAN (c-PAN) in which arthritis developed as the initial clinical episode of disease and we argued, through a review of the literature, the clinical feature of patients presenting with arthritis as the initial symptom of PAN. To our knowledge, only six cases have been reported in the English literature, and all six patients were categorized as having c-PAN. Of those patients, four had arthritis with indicating destructive changes. A median of 9 years elapsed prior to the induction of immunosuppressive treatment despite the fact that the other reviewed cases as well as our two patients, who received treatment significantly earlier, showed no evidence of joint destruction. Taken together, this report suggests that the early induction of therapy based on the definitive diagnosis of PAN may be required for preventing joint disruption even though it is not easy to make a diagnosis of PAN unless biopsied tissue can provide the evidence of necrotizing vasculitis.

11.
Mult Scler Relat Disord ; 29: 145-147, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30711880

RESUMO

Despite having a high rate of occurrence, erythroblast appearance in peripheral blood may not be a recognized adverse effect of natalizumab (NTZ) treatment. Additionally, the time course and cause of erythroblast appearance remain unclear. We report two cases of multiple sclerosis wherein NTZ treatment led to erythroblast appearance in peripheral blood. Erythroblasts appeared after NTZ administration; however, their counts did not increase and the administration of medication was continued. NTZ can inhibit erythroblastic island formation associated with maturing of erythroblast via VLA-4. Clinicians do not need to be afraid; however, careful observation is recommended because some patients may develop anemia.


Assuntos
Eritroblastos/efeitos dos fármacos , Fatores Imunológicos/efeitos adversos , Esclerose Múltipla/tratamento farmacológico , Natalizumab/efeitos adversos , Neurite Óptica/tratamento farmacológico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
J Clin Neurosci ; 61: 264-266, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30470651

RESUMO

A 54-year-old Japanese man had a fever of over 40 °C for 7 days and developed unconsciousness, seizure and respiratory arrest. T2-weighted imaging magnetic resonance imaging revealed high-intensity signals on bilateral thalamus and it gradually extended to the brain white matter. Moreover, the lesion progressed to the spinal gray matter. The patient was diagnosed with acute necrotizing encephalopathy. CPT2 variants have been reported to be associated with acute necrotizing encephalopathy particularly in children and spinal cord lesions are extremely rare. We report a case of ANE in an adult with a CPT2 variant who developed spinal cord lesions.


Assuntos
Encefalopatias/genética , Carnitina O-Palmitoiltransferase/genética , Medula Espinal/patologia , Variação Genética , Humanos , Masculino , Pessoa de Meia-Idade
13.
Intern Med ; 56(15): 2057-2062, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28768981

RESUMO

We herein report the case of a 44-year-old woman who developed protein-losing gastroenteropathy (PLGE) with hypoalbuminemia as the first manifestation of mixed connective tissue disease (MCTD). Albumin leakage from the stomach and intestinal tract was demonstrated by 99mTc-labeled human serum albumin scintigraphy. The patient's response to prednisolone therapy was insufficient; therefore, additional cyclosporin A (CsA) treatment was administered, and clinical remission was achieved. We concluded that although PLGE is a rare complication of MCTD, it may manifest as an initial clinical episode of MCTD. Furthermore, CsA can be a useful treatment option for refractory PLGE related to MCTD.


Assuntos
Doença Mista do Tecido Conjuntivo/complicações , Enteropatias Perdedoras de Proteínas/etiologia , Adulto , Ciclosporina/uso terapêutico , Quimioterapia Combinada , Feminino , Glucocorticoides/uso terapêutico , Humanos , Hipoalbuminemia/diagnóstico por imagem , Hipoalbuminemia/etiologia , Imunossupressores/uso terapêutico , Doença Mista do Tecido Conjuntivo/diagnóstico por imagem , Doença Mista do Tecido Conjuntivo/tratamento farmacológico , Prednisolona/uso terapêutico , Enteropatias Perdedoras de Proteínas/diagnóstico por imagem , Cintilografia , Agregado de Albumina Marcado com Tecnécio Tc 99m
16.
Intern Med ; 57(13): 1953-1954, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29491301
18.
Metabolites ; 3(1): 144-54, 2013 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24957894

RESUMO

In animals, cobalamin (Cbl) is a cofactor for methionine synthase and methylmalonyl-CoA mutase (MCM), which utilizes methylcobalamin and 5'-deoxyadenosylcobalamin (AdoCbl), respectively. The cblA complementation class of inborn errors of Cbl metabolism in humans is one of three known disorders that affect AdoCbl synthesis. The gene responsible for cblA has been identified in humans (MMAA) as well as its homolog (meaB) in Methylobacterium extorquens. Recently, it has been reported that human MMAA plays an important role in the protection and reactivation of MCM in vitro. However, the physiological function of MMAA is largely unknown. In the present study, we isolated the cDNA encoding MMAA from Euglena gracilis Z, a photosynthetic flagellate. The deduced amino acid sequence of the cDNA shows 79%, 79%, 79% and 80% similarity to human, mouse, Danio rerio MMAAs and M. extorquens MeaB, respectively. The level of the MCM transcript was higher in Cbl-deficient cultures of E. gracilis than in those supplemented with Cbl. In contrast, no significant differences were observed in the levels of the MMAA transcript under the same two conditions. No significant difference in MCM activity was observed between Escherichia coli that expressed either MCM together with MMAA or expressed MCM alone.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA