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1.
Nat Commun ; 12(1): 163, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420034

RESUMO

Dynamic combinatorial chemistry applied to biological environments requires the exchange chemistry of choice to take place under physiological conditions. Thiol-disulfide exchange, one of the most popular dynamic combinatorial chemistries, usually needs long equilibration times to reach the required equilibrium composition. Here we report selenocystine as a catalyst mimicking Nature's strategy to accelerate thiol-disulfide exchange at physiological pH and low temperatures. Selenocystine is able to accelerate slow thiol-disulfide systems and to promote the correct folding of an scrambled RNase A enzyme, thus broadening the practical range of pH conditions for oxidative folding. Additionally, dynamic combinatorial chemistry target-driven self-assembly processes are tested using spermine, spermidine and NADPH (casting) and glucose oxidase (molding). A non-competitive inhibitor is identified in the glucose oxidase directed dynamic combinatorial library.


Assuntos
Biomimética/métodos , Cistina/análogos & derivados , Dissulfetos/química , Dobramento de Proteína , Compostos de Sulfidrila/química , Catálise , Ativação Enzimática , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Compostos Organosselênicos , Oxirredução , Ribonuclease Pancreático/química , Ribonuclease Pancreático/metabolismo , Temperatura
2.
Echocardiography ; 36(2): 336-344, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30592779

RESUMO

OBJECTIVES: To evaluate whether carotid disease is associated with coronary artery disease (CAD) extension in patients undergoing treadmill exercise stress echocardiography (EE). METHODS: We retrospectively studied 156 patients without previous vascular disease who underwent EE, carotid ultrasonography, and coronary angiography between 2002 and 2013. Low-, intermediate-, and high-risk EE were defined as negative, localized ischemia, and multivessel/extensive ischemia EE respectively; carotid disease according to Mannheim and American Society of Echocardiography Consensus and CAD extension from zero to three vessel disease as stenosis ≥50% by visual assessment. RESULTS: Of the 156 patients, 67 (42.9%), 43 (27.6%), 22 (14.1%), and 24 (15.4%) had zero, one, two, and three vessel disease respectively. Age (P = 0.047), male sex (P = 0.010), diabetes mellitus (P = 0.039), smoking habit (P = 0.015), fasting plasma glucose (P = 0.021), European Systematic COronary Risk Evaluation (P = 0.003), pretest CAD probability (P = 0.003), high-risk EE (P < 0.001), and carotid plaque presence (CP) (P < 0.001) were associated in univariate analysis with more extensive CAD. Predictors of CAD extension in multivariate analysis were high-risk EE (odds ratio [OR] 2.42, P < 0.001), CP presence (OR 1.75, P = 0.004), and pretest CAD probability >65% (OR 1.49, P = 0.023). CP was also associated with multivessel CAD in the 53 patients with low- or intermediate-risk EE (P = 0.001). CONCLUSIONS: CP is associated with CAD extension in patients with ischemic heart disease suspicion undergoing EE. Patients with CP could benefit from a more aggressive therapeutic strategy regarding patients without carotid disease and similar risk EE, especially in intermediate- and/or low-risk test where guidelines recommend initially optimal medical treatment.


Assuntos
Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/diagnóstico por imagem , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Ecocardiografia sob Estresse/métodos , Idoso , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/patologia , Doenças das Artérias Carótidas/fisiopatologia , Doença da Artéria Coronariana/patologia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Ultrassonografia/métodos
3.
Dis Model Mech ; 5(5): 660-70, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22736460

RESUMO

We have modelled elaidyl-sulfamide (ES), a sulfamoyl analogue of oleoylethanolamide (OEA). ES is a lipid mediator of satiety that works through the peroxisome proliferator-activated receptor alpha (PPARα). We have characterised the pharmacological profile of ES (0.3-3 mg/kg body weight) by means of in silico molecular docking to the PPARα receptor, in vitro transcription through PPARα, and in vitro and in vivo administration to obese rats. ES interacts with the binding site of PPARα in a similar way as OEA does, is capable of activating PPARα and also reduces feeding in a dose-dependent manner when administered to food-deprived rats. When ES was given to obese male rats for 7 days, it reduced feeding and weight gain, lowered plasma cholesterol and reduced the plasmatic activity of transaminases, indicating a clear improvement of hepatic function. This pharmacological profile is associated with the modulation of both cholesterol and lipid metabolism regulatory genes, including the sterol response element-binding proteins SREBF1 and SREBF2, and their regulatory proteins INSIG1 and INSIG2, in liver and white adipose tissues. ES treatment induced the expression of thermogenic regulatory genes, including the uncoupling proteins UCP1, UCP2 and UCP3 in brown adipose tissue and UCP3 in white adipose tissue. However, its chronic administration resulted in hyperglycaemia and insulin resistance, which represent a constraint for its potential clinical development.


Assuntos
Amidas/farmacologia , Colesterol/sangue , Ácidos Oleicos/farmacologia , PPAR alfa/agonistas , Sulfonamidas/farmacologia , Aumento de Peso/efeitos dos fármacos , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Amidas/administração & dosagem , Amidas/química , Animais , Glicemia/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Teste de Tolerância a Glucose , Humanos , Ligação de Hidrogênio/efeitos dos fármacos , Insulina/sangue , Resistência à Insulina , Ligantes , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Modelos Moleculares , Ácidos Oleicos/administração & dosagem , Ácidos Oleicos/química , Oxazóis/química , Oxazóis/farmacologia , PPAR alfa/metabolismo , Ligação Proteica/efeitos dos fármacos , Ratos , Soluções , Sulfonamidas/administração & dosagem , Sulfonamidas/química , Paladar , Termogênese/efeitos dos fármacos , Termogênese/genética , Tirosina/análogos & derivados , Tirosina/química , Tirosina/farmacologia
4.
Rev Esp Cardiol ; 56(2): 152-9, 2003 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-12605760

RESUMO

INTRODUCTION: The transradial approach has emerged as an attractive alternative to the femoral approach for coronary angiography and interventions. We describe our experience with the transradial approach and analyze the influence of the learning curve. PATIENTS AND METHODS: The transradial approach was attempted in patients with a good radial pulse and normal Allen test. When feasible and clinically indicated, we attempted ad hoc intervention. We divided the study population into two groups: Group A (the first 200 cases) and B (all other patients). We compared the radial group with a matched femoral control group. RESULTS: We attempted the transradial approach in 526 patients (77.6% male; age 63.5 +/- 11.51), and obtained a success rate of 93.7%. We found differences between group A and B in the success rate (91.0 vs 95.4%, p = 0,04), duration of procedure [23 (16-29) vs. 19 (15-24) minutes; p < 0.001], and fluoroscopy time [6.4 (4.2-10) vs. 5.0 (3.0-7.7) minutes; p < 0,001]. At 24 h of follow-up, we found small hematomas in 9.4%, bleeding in 4.9%, and radial artery obstruction in 2.8%, with no cases of arteriovenous fistula, pseudoaneurysm, or need for vascular surgery. We attempted intervention in 169 patients with 258 lesions, achieving angiographic success in 96.1%. We found no differences in the characteristics of the lesions and patients, or in the angiographic success rate of the radial and femoral PTCA groups. CONCLUSIONS: The transradial approach is a safe and effective alternative to femoral catheterization. There is a significant learning curve associated with the successful performance of transradial procedures.


Assuntos
Angioplastia Coronária com Balão/métodos , Angiografia Coronária/métodos , Artéria Radial , Angioplastia Coronária com Balão/educação , Cateterismo Cardíaco/métodos , Cateteres de Demora/estatística & dados numéricos , Feminino , Artéria Femoral , Humanos , Aprendizagem , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias
5.
Rev Esp Cardiol ; 55(7): 738-50, 2002 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-12113702

RESUMO

Understanding of the pathophysiology of atherosclerosis has changed markedly over the past few decades. It is now widely accepted that inflammation plays a fundamental role in the genesis and development of atherosclerosis. Inflammatory mechanisms also appear to determine clinical presentation and disease outcome. Atherosclerotic lesions have high concentrations of inflammatory cells (T lymphocytes and activated macrophages) as well as an abundance of pro-inflammatory cytokines [interleukin (IL)-1, IL-6, IL-8, interferon-gamma, tumor necrosis factor-alpha, etc.] that modulate local inflammatory responses. These may also alter plaque stability and facilitate the development of acute cardiovascular events. The role of anti-inflammatory cytokines in this context remains to be studied. IL-10 is an anti-inflammatory cytokine synthesised by T-lymphocytes and macrophages and has other anti-inflammatory effects. IL-10 expression within human atherosclerotic plaques has been demonstrated and animal experiments have shown that low levels of IL-10 lead to the development of extensive and unstable atherosclerotic lesions. Currently available evidence suggests a potential protective role for IL-10 in atherosclerosis. This new perspective on coronary disease as a chronic inflammatory process may open new avenues for the management of ischemic heart disease.


Assuntos
Doença das Coronárias/tratamento farmacológico , Interleucina-10/uso terapêutico , Animais , Arteriosclerose/tratamento farmacológico , Arteriosclerose/etiologia , Arteriosclerose/fisiopatologia , Ensaios Clínicos como Assunto , Doença das Coronárias/fisiopatologia , Endotélio Vascular/fisiopatologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/fisiopatologia , Interleucina-10/fisiologia , Lipoproteínas LDL/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Prognóstico , Trombose/etiologia
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