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1.
World J Cardiol ; 9(6): 553-557, 2017 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-28706591

RESUMO

AIM: To conduct a review of "interferon related pericarditis". METHODS: We searched MEDLINE, EMBASE, Cinahl, and the Cochrane Database from the earliest available date through September 2016. A search strategy using the Medical Subject Headings and text keywords "interferon" and "pericarditis" were used. RESULTS: Nine case reports were eligible for the present study. Six of 8 cases were women and the mean age was 43.8 ± 13.8 years with chronic hepatitis C in 6 cases, malignant melanoma in 2 cases and chronic myelogenous leukemia in 1 case. The patients complained of chest pain in 6 cases, dyspnea in 5 cases and edema in 2 cases. Pericardial friction rub was heard in 3 of 9 cases. Congestive heart failure occurred in 3 of 9 cases. Two mechanisms for pericarditis were demonstrated, one is autoimmune included lupus like syndrome in 2 cases and the other is cardio toxicity in 4 cases. Treatment of interferon related pericarditis is discontinuation of Interferon treatment. Four of 9 cases were treated with prednisone and 4 with nonsteroidal anti-inflammatory drugs. CONCLUSION: Interferon related pericarditis still remains uncertain. Treatment of interferon related pericarditis rests mainly on early recognition and drug discontinuation. Interferon related pericarditis was treated with steroid and/or nonsteroidal anti-inflammatory drugs.

2.
World J Cardiol ; 3(10): 329-36, 2011 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-22053221

RESUMO

AIM: To evaluate the association between genetic polymorphisms and angiotensin converting enzyme inhibitor (ACEI)-related cough, and the race- or ethnicity-related difference in the prevalence of cough attributed to ACEI therapy. METHODS: We conducted a search in PubMed, EMBASE, Cinahl, and the Cochrane Database without language limitation. A database of 11 studies on ACEI-related cough, with detailed information regarding ACE I/D or bradykinin B(2) receptor polymorphisms, was created. Eligible studies were synthesized using meta-analysis methods, including cumulative meta-analysis. A subgroup analysis was also performed using ethnicity. RESULTS: Six studies were included on ACE I/D polymorphism (398 Caucasians, 723 East Asians), and three studies were included on bradykinin B(2) receptor polymorphism (300 East Asians). The distribution of ACE genotypes showed significant differences in the entire population (P = 0.004) and in East Asians (P = 0.005) but not in Caucasians (P = 0.23). Allelic frequencies of ACE showed significant differences in East Asians [odds ratio (OR) = 1.49 (1.11-2.02)]. The meta-analysis with a random effects model showed a significant association between ACE allele I/D and ACEI-related cough [random effects (RE) OR = 1.49 (1.11-2.02), P = 0.009] in East Asians, but not in Caucasians [RE OR = 0.90 (0.60-1.35)]. The allelic frequencies of the bradykinin B(2) receptor gene were significantly different [OR = 2.25 (1.42-3.57)]. The distributions of the T/C genotypes of the bradykinin B(2) receptor gene were significantly different (χ(2) = 8.366, P = 0.015). The meta-analyses revealed that there was a significant association between the bradykinin B(2) receptor allele and ACEI-related cough in East Asians [RE OR = 2.29 (1.42-3.69), P = 0.001]. CONCLUSION: ACE I/D and Bradykinin B(2) receptor polymorphisms contributed to the risk of ACEI-related cough in East Asians, but a negative association between ACE I/D polymorphism and ACEI-related cough was observed in Caucasians.

3.
Cardiovasc Revasc Med ; 12(4): 197-202, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21489889

RESUMO

AIMS: The aim of this study was to examine outcome subsequent to implantation of bare-metal stents (BMS) with pioglitazone, which are novel insulin-sensitizing agents, and drug-eluting stents (DES) in patients with diabetes. METHODS AND RESULTS: A total of 139 consecutive Type 2 diabetic patients treated with stent were followed up for 3 years. Data on death, myocardial infarction (MI), target lesion revascularization (TLR), and stent thrombosis were ascertained from January 2003 to January 2006. Eighty-nine patients were treated with a BMS with pioglitazone, and 50 patients were treated with a DES. The incidence of MI was 1.1% in the BMS with pioglitazone group, 4.0% in the DES group [relative risk RR):0.52; 95% CI: 0.10-2.56]. The incidence of TLR was 22.5% in the BMS with pioglitazone group, 28.0% in the DES group (RR 0.89; 95% CI: 0.65-1.22). The incidence of stent thrombosis was 1.0% in the BMS with pioglitazone group, 4.0% in the DES group (RR 0.52; 95% CI: 0.10-2.56). Overall 3-year mortality was similar in the two groups (RR 0.77; 95% CI: 0.34-1.74). CONCLUSIONS: During 3 years of follow-up, patients treated with BMS with pioglitazone had similar risks of death, TLR, MI, and stent thrombosis compared with patients treated with DES.


Assuntos
Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/cirurgia , Diabetes Mellitus Tipo 2/complicações , Hipoglicemiantes/uso terapêutico , Stents , Tiazolidinedionas/uso terapêutico , Idoso , Angiografia Coronária , Reestenose Coronária/complicações , Stents Farmacológicos , Feminino , Seguimentos , Humanos , Hipoglicemiantes/administração & dosagem , Masculino , Infarto do Miocárdio/complicações , Pioglitazona , Risco , Estatísticas não Paramétricas , Tiazolidinedionas/administração & dosagem , Resultado do Tratamento
4.
World J Hepatol ; 2(9): 358-61, 2010 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-21161021

RESUMO

We report a case of pericarditis and chronic inflammatory demyelinating polyneuropathy with biological signs of a lupus-like syndrome due to pegylated interferon alfa-2a therapy during treatment for chronic hepatitis C. The patient developed moderate weakness in the lower limbs and dyspnea. He was hospitalized for congestive heart failure. An electrocardiogram showed gradual ST-segment elevation in leads V(1) through V(6) without coronary artery disease. A transthoracic cardiac ultrasonographic study revealed moderate pericardial effusion with normal left ventricular function. Anti-DNA antibody and antids DNA IgM were positive. Neurological examination revealed a symmetrical predominantly sensory polyneuropathy with impairment of light touch and pin prick in globe and stoking-like distribution. Treatment with prednisolone improved the pericarditis and motor nerve disturbance and the treatment with intravenous immunoglobulin improved the sensory nerve disturbance.

5.
Cardiovasc Revasc Med ; 11(4): 227-31, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20934654

RESUMO

OBJECTIVE: Thiazolidinediones (TZDs) are used in patients with Type 2 diabetes mellitus, but evidence is mixed regarding the influence of medications of this class on target vessel revascularization. The aim of this meta-analysis is to evaluate the effect of TZDs on repeat target vessel revascularization following percutaneous coronary intervention. RESEARCH DESIGN AND METHODS: We searched Medline, EMBASE, Cinahl, and the Cochrane Database from earliest available date through December 2007. Criteria for inclusion in our meta-analysis included the use of randomized control trial and the availability of target vessel revascularization. Relative risks (RRs) with 95% confidence intervals (CIs) of target vessel revascularization (TVR) and restenosis were estimated using a fixed-effects meta-analysis of seven randomized controlled trials (n=347, including 178 receiving pioglitazone and 169 receiving rosiglitazone). RESULTS: One hundred seventy-eight patients were treated with pioglitazone, and 169 were treated with rosiglitazone. Pioglitazone is associated with a significantly lower risk of target vessel revascularization or restenosis (TVR: n=37/96 vs. 7/94; RR, 5.91; 95% CI, 3.00-11.7; P<.0001, restenosis: n=42/96 vs. 8/94; RR, 6.48; 95% CI, 3.37-12.4; P<.0001). Rosiglitazone had no effect on target vessel revascularization (n=56/131 vs. 51/124; RR, 1.11; 95% CI, 0.63-1.96; P=.793). CONCLUSIONS: Pioglitazone is associated with a significantly decreased risk of target vessel revascularization, but rosiglitazone does not reduce the risk of target vessel revascularization following percutaneous coronary intervention.


Assuntos
Angioplastia com Balão/instrumentação , Doença da Artéria Coronariana/terapia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Metais , Stents , Tiazolidinedionas/uso terapêutico , Idoso , Angioplastia com Balão/efeitos adversos , Distribuição de Qui-Quadrado , Doença da Artéria Coronariana/complicações , Reestenose Coronária/etiologia , Diabetes Mellitus Tipo 2/complicações , Humanos , Hipoglicemiantes/efeitos adversos , Pessoa de Meia-Idade , Pioglitazona , Desenho de Prótese , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Fatores de Risco , Rosiglitazona , Tiazolidinedionas/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
6.
Cardiovasc Revasc Med ; 10(1): 5-11, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19159848

RESUMO

BACKGROUND: Drug-eluting stents (DESs) have been shown to decrease restenosis as compared with bare-metal stents. Recently, thiazolidinediones effectively reduced restenosis and the risk of repeat target vessel revascularization. We conducted a study to compare the performance of a DES with that of a bare-metal stent with pioglitazone in patients with Type 2 diabetes mellitus (DM). METHODS: The study was a prospective cohort trial involving 38 Type 2 diabetic patients referred for coronary stenting who were assigned to either the sirolimus-eluting stent (SES) group or the pioglitazone group. Quantitative coronary angiography was performed at study entry and at 6 months of follow-up to evaluate in-stent late luminal loss and the percentage of the luminal diameter and the rate of restenosis. We also analyzed major adverse cardiac events (MACE) at 12 months. RESULTS: There were no significant differences in glycemic control levels or in lipid levels in the two groups at follow up. The insulin and homeostasis model assessment insulin resistance at follow-up were significantly lower in the pioglitazone group than in the SES group. The percentage of restenosis was similar between the SES group and the pioglitazone group. The incidence of MACE at 1 year tended to be lower in the pioglitazone group than in the SES group. CONCLUSIONS: The bare-metal stent with pioglitazone is not inferior to the SES in the present study and is one of therapeutic strategies of percutaneous coronary intervention for patients with DM.


Assuntos
Angioplastia Coronária com Balão/instrumentação , Fármacos Cardiovasculares/administração & dosagem , Estenose Coronária/terapia , Diabetes Mellitus Tipo 2/terapia , Stents Farmacológicos , Hipoglicemiantes/uso terapêutico , Metais , Sirolimo/administração & dosagem , Stents , Tiazolidinedionas/uso terapêutico , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Glicemia/efeitos dos fármacos , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Angiografia Coronária , Reestenose Coronária/etiologia , Reestenose Coronária/prevenção & controle , Estenose Coronária/complicações , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Humanos , Insulina/sangue , Resistência à Insulina , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Pioglitazona , Estudos Prospectivos , Desenho de Prótese , Fatores de Tempo , Resultado do Tratamento
7.
J Cardiometab Syndr ; 3(4): 200-4, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19040587

RESUMO

The aim of this study was to evaluate the effect of pioglitazone on nitric oxide in patients with type 2 diabetes and coronary artery disease. Twenty-seven patients with coronary artery disease and diabetes mellitus who had received coronary stenting were eligible for the study. They were assigned to the no insulin resistance (NIR) group, the insulin resistance (IR) group, and the pioglitazone group (30 mg once a day). Endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-alpha), interleukin-6, leptin, and adiponectin were measured. In the pioglitazone group, eNOS, iNOS, and leptin were significantly lower and adiponectin was significantly higher than those in the IR group. Stepwise multiple regression analyses showed that eNOS correlated with TNF-alpha and iNOS correlated with leptin and TNF-alpha. Leptin was the strongest predictor of iNOS. Treatment with pioglitazone significantly reduced eNOS and iNOS by improving adipocytokine levels.


Assuntos
Diabetes Mellitus Tipo 2/enzimologia , Hipoglicemiantes/uso terapêutico , Óxido Nítrico Sintase/efeitos dos fármacos , Tiazolidinedionas/uso terapêutico , Idoso , Angioplastia Coronária com Balão/métodos , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/enzimologia , Doença da Artéria Coronariana/terapia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ensaio de Imunoadsorção Enzimática , Seguimentos , Humanos , Hipoglicemiantes/administração & dosagem , Resistência à Insulina , Masculino , Óxido Nítrico Sintase/sangue , Óxido Nítrico Sintase Tipo II/sangue , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Óxido Nítrico Sintase Tipo III/sangue , Óxido Nítrico Sintase Tipo III/efeitos dos fármacos , Pioglitazona , Tiazolidinedionas/administração & dosagem , Resultado do Tratamento
8.
Small ; 3(11): 1950-6, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17935079

RESUMO

The cavity of the toroidal protein TRAP (trp RNA-binding attenuation protein) is modified to capture gold nanodots in solution. By engineering a titanium-binding peptide onto one surface of the ring it is also possible to bind it specifically and tightly to a TiO2 surface. TRAP bound in this way is then used to capture gold nanodots and attach them to prepared surfaces. Gold-protein complexes are observed using atomic force microscopy and transmission electron microscopy. The modified TRAP is used to build gold nanodots into the SiO2 layer of a metal oxide semiconductor. This is the first use of a ring protein, rather than the more commonly used spherical protein cages, to constrain nanodots to a surface. This method is an important addition to the current range of bionanotechnology tools and may be the basis for future, multicomponent electronic devices.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/ultraestrutura , Cristalização/métodos , Ouro/química , Nanosferas/química , Nanosferas/ultraestrutura , Nanotecnologia/métodos , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/ultraestrutura , Fatores de Transcrição/química , Fatores de Transcrição/ultraestrutura , Sítios de Ligação , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Ligação Proteica , Propriedades de Superfície
9.
Int J Cardiol ; 115(3): 354-60, 2007 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-16806535

RESUMO

BACKGROUND: Sleep disordered breathing has been reported to be associated with congestive heart failure (CHF). Nocturnal oxygen has been shown to abolish apnea. The aim of this study is to examine whether nocturnal oxygen reduces sympathetic nerve activity, and prevents progress of CHF. METHODS: 93 patients with left ventricular ejection fractions < 60%, were examined with overnight saturation monitoring for an oxygen desaturation index. Subjects with oxygen desaturation of 4% > or = 4/h were examined with polysomnography. Apnea-hypopnea index (AHI) was calculated as the total number of episodes of apnea and hypopnea per hour of sleep. We started nocturnal oxygen for the patients with AHI > or = 20. Urinary and plasma catecholamines concentrations, serum brain natriuretic peptide, human atrial natriuretic peptide, and endothelial nitric oxide synthase levels were measured before and after starting oxygen. RESULTS: Compared among the three groups, CHF with central sleep apnea (CHF-CSA) group had significantly higher 24-h urinary adrenaline (CHF-CSA: 4.411+/-2.940 micromol/day, CHF with obstructive sleep apnea (CHF-OSA): 2.686+/-1.084 micromol/day, CHF without apnea (CHF-N): 3.178+/-1.778 micromol/day, P<0.05). Oxygen therapy significantly decreased AHI and 4 serum BNP levels (from 91.75+/-80.35 pg/ml to 52.75+/-45.70 pg/ml, mean change=33.85 pg/ml, P=0.0208). Serum eNOS levels were lower in CHF-CSA group and CHF-OSA group than in CHF-N group (CHF-CSA: 15.89+/-10.75 pg/ml, CHF-OSA: 7.46+/-3.91 pg/ml, CHF-N: 27.33+/-14.83 pg/ml, P<0.05). CONCLUSIONS: Nocturnal oxygen may prevent progress of CHF with central sleep apnea.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Consumo de Oxigênio/fisiologia , Oxigenoterapia/métodos , Apneia do Sono Tipo Central/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ritmo Circadiano , Progressão da Doença , Feminino , Seguimentos , Insuficiência Cardíaca/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Óxido Nítrico/sangue , Oximetria , Probabilidade , Valores de Referência , Medição de Risco , Índice de Gravidade de Doença , Apneia do Sono Tipo Central/diagnóstico , Volume Sistólico/fisiologia , Sistema Nervoso Simpático/fisiologia , Resultado do Tratamento
11.
Cardiovasc Revasc Med ; 7(2): 54-60, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16757401

RESUMO

BACKGROUND: Recent studies have shown that insulin resistance (IR) is an independent predictor of early restenosis after coronary stenting. The aim of this study was to examine the effects of IR and its linkage to late loss with bare metal stenting in nondiabetic patients with acute myocardial infarction (AMI). MATERIALS AND METHODS: We enrolled 61 nondiabetic patients with AMI who have undergone coronary stenting. Quantitative analyses of coronary angiographic data before and after the procedure and at 4 months were performed. Fasting plasma glucose (FPG) and insulin were measured every week until the subjects' hospital discharge. Stress hormones, endothelial nitric oxide synthase, tumor necrosis factor alpha, interleukin-6, leptin, and adiponectin were measured on admission and at 4 months after coronary stenting. RESULTS: Simple linear regression analyses showed a relationship between FPG and insulin [IR group: r=0.297, P=.0428; no insulin resistance (NIR) group: r=0.539, P=.0466] and that late loss was associated with the homeostasis model assessment of IR (HOMA-IR) at 4 months (r=0.435, P=.03). At multiple regression analyses, HOMA-IR on admission in the IR group significantly correlated with thyroid-stimulating hormone, glucagon, and cortisol. The HOMA-IR at 4 months correlated with leptin. CONCLUSIONS: Nondiabetic patients with AMI can be classified into two groups: the IR group and the NIR group. The IR consisted of the transient IR, which correlated with stress hormones, and the continuous IR, which correlated with leptin and contributed to restenosis after coronary stenting.


Assuntos
Resistência à Insulina/fisiologia , Infarto do Miocárdio/sangue , Infarto do Miocárdio/fisiopatologia , Idoso , Diabetes Mellitus/sangue , Diabetes Mellitus/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/cirurgia , Stents
12.
Diabetes Care ; 29(1): 101-6, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16373904

RESUMO

OBJECTIVE: Recent studies have demonstrated that the treatment with thiazolidinediones reduces in-stent restenosis. The aim of this study was to elucidate the mechanism of the efficacy of pioglitazone for preventing in-stent restenosis in type 2 diabetic patients. RESEARCH DESIGN AND METHODS: We conducted a prospective, randomized trial involving 54 type 2 diabetic patients referred for coronary stenting who were randomly assigned to either the control or the pioglitazone group. Quantitative coronary angiography was performed at study entry and at 6 months follow-up. Endothelial nitric oxide synthase (eNOS), tumor necrosis factor alpha, interleukin-6, leptin, and adiponectin were measured at study entry and at 6 months follow-up. RESULTS: A total of 28 patients were randomly assigned to the control group, and 26 patients were assigned to the pioglitazone group. There were no significant differences in glycemic control levels or in lipid levels in the two groups at baseline or at follow-up. Insulin, homeostasis model assessment of insulin resistance, eNOS, and leptin at follow-up were significantly reduced in the pioglitazone group compared with the control group. The late luminal loss and in-stent restenosis were significantly less in the pioglitazone group than in the control group. Leptin independently correlated with late luminal loss at multiple regression analysis. CONCLUSIONS: The treatment with pioglitazone in type 2 diabetic patients significantly reduced leptin. This decreased leptin improved insulin resistance and endothelial function with the reduction of insulin. The improved endothelial function affected the reduction of in-stent restenosis.


Assuntos
Doença das Coronárias/cirurgia , Reestenose Coronária/prevenção & controle , Diabetes Mellitus Tipo 2/tratamento farmacológico , Angiopatias Diabéticas/cirurgia , Hipoglicemiantes/uso terapêutico , Stents , Tiazolidinedionas/uso terapêutico , Idoso , Pressão Sanguínea , Citocinas/sangue , Feminino , Humanos , Masculino , Óxido Nítrico Sintase Tipo III/sangue , Pioglitazona , Fatores de Risco
13.
Int J Cardiol ; 103(2): 128-34, 2005 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-16080969

RESUMO

PURPOSE: The rationale of this study was to determine whether insulin resistance is an independent risk factor for restenosis after coronary stenting. BACKGROUND: Previous studies suggested that hyperinsulinemia may be an important risk factor for ischemic heart disease. Restenosis after coronary stenting is neointimal tissue proliferation and de-novo stenosis is atherosclerosis from the point of view of histology. However, it has not been determined whether insulin resistance is independently related to restenosis after coronary stenting. METHODS: Clinical variables of unselected population of 110 patients were analyzed in multivariate logistic regression analyses for both restenosis and de-novo stenosis. Clinical, lesion-related, and procedural variables were analyzed by chi-square analysis, and relative risk. RESULTS: Multivariate logistic regression analysis showed that homeostasis model assessment insulin resistance (HOMA-IR) and HbA1c were associated with restenosis after coronary stenting (HOMA-IR; P=0.0447, HbA1c; P=0.0462), and HbA1c and low-density lipoprotein cholesterol (LDL-C) were associated with de-novo stenosis (HbA1c; P=0.0201, LDL-C; P=0.0204). Restenosis was influenced by insulin resistance [Relative Risk (RR) 2.06; 95 percent confidence interval (95%CI) 1.20 to 3.56], diabetes mellitus (DM: RR 1.92; 95%CI 1.25 to 2.95), and final minimal lumen diameter (RR 2.83; 95%CI 1.32 to 6.06). CONCLUSIONS: HOMA-IR and DM are the predictors of restenosis after coronary stenting, and HbA1c and LDL-C are the predictors of de-novo stenosis. These results may be reflected in histological differences between neointimal tissue proliferation as restenosis and atherosclerosis as de-novo stenosis.


Assuntos
Reestenose Coronária/metabolismo , Resistência à Insulina , Stents , Idoso , Idoso de 80 Anos ou mais , Angioplastia Coronária com Balão , Biomarcadores/sangue , Implante de Prótese Vascular , Reestenose Coronária/sangue , Estenose Coronária/metabolismo , Estenose Coronária/terapia , Diabetes Mellitus Tipo 2/sangue , Feminino , Teste de Tolerância a Glucose , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Fatores de Risco , Resultado do Tratamento
14.
Plant Cell ; 16(4): 993-1007, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15031412

RESUMO

The biosynthesis of iron-sulfur clusters is a highly regulated process involving several proteins. Among them, so-called scaffold proteins play pivotal roles in both the assembly and delivery of iron-sulfur clusters. Here, we report the identification of two chloroplast-localized NifU-like proteins, AtCnfU-V and AtCnfU-IVb, from Arabidopsis (Arabidopsis thaliana) with high sequence similarity to a cyanobacterial NifU-like protein that was proposed to serve as a molecular scaffold. AtCnfU-V is constitutively expressed in several tissues of Arabidopsis, whereas the expression of AtCnfU-IVb is prominent in the aerial parts. Mutant Arabidopsis lacking AtCnfU-V exhibited a dwarf phenotype with faint pale-green leaves and had drastically impaired photosystem I accumulation. Chloroplasts in the mutants also showed a decrease in both the amount of ferredoxin, a major electron carrier of the stroma that contains a [2Fe-2S] cluster, and in the in vitro activity of iron-sulfur cluster insertion into apo-ferredoxin. When expressed in Escherichia coli cells, AtCnfU-V formed a homodimer carrying a [2Fe-2S]-like cluster, and this cluster could be transferred to apo-ferredoxin in vitro to form holo-ferredoxin. We propose that AtCnfU has an important function as a molecular scaffold for iron-sulfur cluster biosynthesis in chloroplasts and thereby is required for biogenesis of ferredoxin and photosystem I.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ferredoxinas/biossíntese , Proteínas Ferro-Enxofre/metabolismo , Complexo de Proteína do Fotossistema I/biossíntese , Sequência de Aminoácidos , Arabidopsis/genética , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Bactérias/genética , Cloroplastos/metabolismo , Cianobactérias/genética , DNA Bacteriano/genética , Dimerização , Transporte de Elétrons , Expressão Gênica , Genes de Plantas , Proteínas Ferro-Enxofre/química , Proteínas Ferro-Enxofre/genética , Modelos Biológicos , Dados de Sequência Molecular , Mutação , Fenótipo , Complexo de Proteína do Fotossistema I/química , Subunidades Proteicas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
15.
Circ J ; 67(1): 16-20, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12520145

RESUMO

A single nucleotide polymorphism of mitochondrial 5178A/C, causing a Met to Leu replacement within the NADH dehydrogenase subunit, is reported to be associated with longevity. The purpose of the present study was to assess the contribution of mitochondrial polymorphisms, particularly the 5178A/C genotype, to the susceptibility to acute myocardial infarction (AMI) in a Japanese study population. There were 4 groups: 150 patients with AMI, 150 with essential hypertension, 100 with diabetes mellitus, and 150 subjects matched for age and sex who served as the control group. Mitochondrial 5178A/C was detected by the polymerase chain reaction restriction fragment length polymorphism method. The allelic frequency of 5178C was significantly higher in the AMI group than in the control group, and this difference was more marked in younger patients. There were differences in allelic frequencies among the essential hypertension group, diabetes mellitus group and control group, but a higher frequency of the C allele was seen in the AMI group compared with the essential hypertension and diabetes mellitus groups. This particular polymorphism was found to be associated with development of AMI, especially in younger patients and constitutes a new risk factor for AMI.


Assuntos
DNA Mitocondrial/genética , Infarto do Miocárdio/genética , Idoso , Envelhecimento/fisiologia , Alelos , Substituição de Aminoácidos , Complicações do Diabetes , Feminino , Frequência do Gene , Predisposição Genética para Doença/genética , Genótipo , Humanos , Hipercolesterolemia/complicações , Hipertensão/complicações , Leucina , Masculino , Metionina , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , Fatores de Risco
16.
Proc Natl Acad Sci U S A ; 99(21): 13448-52, 2002 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-12357031

RESUMO

ATP synthase F(o)F(1) (alpha(3)beta(3)gammadelta epsilon ab(2)c(10-14)) couples an electrochemical proton gradient and a chemical reaction through the rotation of its subunit assembly. In this study, we engineered F(o)F(1) to examine the rotation of the catalytic F(1) beta or membrane sector F(o) a subunit when the F(o) c subunit ring was immobilized; a biotin-tag was introduced onto the beta or a subunit, and a His-tag onto the c subunit ring. Membrane fragments were obtained from Escherichia coli cells carrying the recombinant plasmid for the engineered F(o)F(1) and were immobilized on a glass surface. An actin filament connected to the beta or a subunit rotated counterclockwise on the addition of ATP, and generated essentially the same torque as one connected to the c ring of F(o)F(1) immobilized through a His-tag linked to the alpha or beta subunit. These results established that the gamma epsilon c(10-14) and alpha(3)beta(3)deltaab(2) complexes are mechanical units of the membrane-embedded enzyme involved in rotational catalysis.


Assuntos
ATPases Translocadoras de Prótons/química , Actinas/química , Actinas/metabolismo , Trifosfato de Adenosina/metabolismo , Dicicloexilcarbodi-Imida/farmacologia , Escherichia coli/enzimologia , Escherichia coli/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Membranas/enzimologia , Membranas Artificiais , Microscopia Eletrônica , Modelos Moleculares , Engenharia de Proteínas , Subunidades Proteicas , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Rotação
17.
FEBS Lett ; 519(1-3): 123-7, 2002 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-12023030

RESUMO

IscA homologs are known to be involved in iron-sulfur cluster formation in various organisms. Recombinant proteins of two IscA homologs from the cyanobacterium Synechocystis PCC 6803, designated SLR1417 and SLR1565, were purified. The absorption spectrum of purified SLR1565 was typical for [2Fe-2S] cluster-containing proteins, whereas that of SLR1417 predominantly showed the presence of the iron ion alone. In the cyanobacterial cell extracts, only SLR1565 was found to form a complex with a novel prokaryotic HEAT-repeats-containing protein, SLR1098. Thus, the two cyanobacterial IscA protein homologs exist in distinct molecular states, suggesting different cellular roles for these proteins.


Assuntos
Proteínas de Bactérias/química , Proteínas de Transporte/química , Proteínas Ferro-Enxofre/química , Azotobacter vinelandii , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Cromatografia em Gel , Cianobactérias , Eletroforese em Gel de Poliacrilamida , Escherichia coli , Proteínas Ferro-Enxofre/genética , Proteínas Ferro-Enxofre/metabolismo , Substâncias Macromoleculares , Dados de Sequência Molecular , Peso Molecular , Ligação Proteica , Sequências Repetitivas de Aminoácidos , Homologia de Sequência de Aminoácidos , Análise Espectral , Frações Subcelulares/química
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