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1.
Ann Rheum Dis ; 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35595388

RESUMO

OBJECTIVE: To determine contributions and functions of autoantibodies (Abs) directed to the angiotensin receptor type 1 (AT1R), which are suggested to be involved in the pathogenesis of AT1R Abs-related diseases such as systemic sclerosis (SSc). METHODS: C57BL/6J mice were immunised with membrane-embedded human AT1R or empty membrane as control. Mice deficient for CD4+ or CD8+ T cells and B cells were immunised with membrane-embedded AT1R or an AT1R peptide proposed to be a dominant T cell epitope. A monoclonal (m)AT1R Ab was generated by hybridoma technique and transferred into C57BL/6J and AT1Ra/b knockout mice. The induced phenotype was examined by histology, immunohistochemistry, immunofluorescence, apoptosis assay and ELISA. In vitro, Abs responses towards AT1R were measured in cells of different origins and species. RESULTS: AT1R-immunised mice developed perivascular skin and lung inflammation, lymphocytic alveolitis, weak lung endothelial apoptosis and skin fibrosis accompanied by Smad2/3 signalling, not present in controls or mice deficient for CD4+ T and B cells. The AT1R peptide 149-172 provoked lung inflammation. Application of the mAT1R Ab induced skin and lung inflammation, not observed in AT1Ra/b knockout mice. In vitro, AT1R Abs activated rat cardiomyocytes and human monocytes, enhanced angiotensin II-mediated AT1R activation in AT1R-transfected HEK293 cells via AT1R binding and mAT1R Ab-activated monocytes mediated the induction of profibrotic markers in dermal fibroblasts. CONCLUSION: Our immunisation strategy successfully induced AT1R Abs, contributing to inflammation and, possibly, to fibrosis via activation of AT1R. Therefore, AT1R Abs are valuable targets for future therapies of SSc and other AT1R Ab-related diseases.

2.
Prostate ; 77(5): 458-465, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27882567

RESUMO

BACKGROUND: Over-stimulation of G-protein coupled receptors (GPCRs) such as α1-adrenergic, muscarinic, endothelin, and AT1 receptors is considered to drive benign prostatic hyperplasia (BHP) which is often associated with lower urinary tract syndrome (LUTS). However, in addition to physiologic GPCR ligands, there is a new class of autoantibodies called functional autoantibodies that target the same GPCRs (GPCR-AABs) for over-stimulation, thus, presenting pathogenic potency. We hypothesize that patients with BPH/LUTS could carry GPCR-AABs representing potential targets for treatment. METHODS: GPCR-AABs were identified, quantified, and characterized in the serum from 20 patients (aged 55-82 years, median 71 years) with BPH using the bioassay of spontaneously beating cultured neonatal rat cardiomyocytes. RESULTS: A sum of 60% of the patients were positive for agonistic autoantibodies directed against the endothelin A receptor (ETA-AABs). ETA-AABs were associated with the IgG 1 subclass, targeted an epitope located on the second extracellular receptor loop and their agonistic activity could be neutralized by the aptamer BC007. CONCLUSIONS: Agonistic ETA-AABs could-via uncontrolled over-boarding endothelin A receptor stimulation-contribute to the pathogenesis of BPH/LUTS. The in vitro demonstrated ETA-AAB neutralization by the aptamer BC007 could open the door for a new treatment strategy in patients with BPH/LUTS. Prostate 77:458-465, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Autoanticorpos/sangue , Hiperplasia Prostática/sangue , Hiperplasia Prostática/diagnóstico , Receptor de Endotelina A/sangue , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Autoanticorpos/genética , Biomarcadores/sangue , Células Cultivadas , Humanos , Masculino , Pessoa de Meia-Idade , Miócitos Cardíacos/metabolismo , Hiperplasia Prostática/genética , Ratos , Receptor de Endotelina A/genética
3.
J Clin Apher ; 31(4): 368-74, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26011726

RESUMO

Reflex sympathetic dystrophy, also known as complex regional pain syndrome (CRPS), has recently been shown to be associated with autoantibodies against ß2-adrenergic and muscarinic M2 receptors. In addition to pain and sudomotor/vasomotor symptoms, dysautonomia is also observed in a subset of CRPS patients. Despite its severity, there are few effective therapies for CRPS described to date. We report a case of a 14-year-old girl with CRPS of her right leg and dysautonomia (gastroparesis, postural tachycardia) refractory to multiple therapies, successfully treated with therapeutic plasma exchange (TPE) with albumin replacement. The patient, who has serum anti ß2-adrenergic and muscarinic M2 receptor autoantibodies in addition to nicotinic acetylcholine receptor ganglionic autoantibodies, underwent an initial course of five TPEs over a 2-week period. She demonstrated a clinical response to TPE as manifested by a rapid improvement in her fatigue and gastroparesis, with a gradual yet significant improvement in her leg pain and sudomotor/vasomotor flares. Following the loading procedures, the patient was treated with rituximab. She continues to require periodic TPE to maintain a remission, with additional immunosuppression being considered long term. Although further studies are needed, TPE (in combination with immunosuppression) may be an appropriate therapy for CRPS patients with detectable autoantibodies, as it is for better characterized diseases with autoantibodies against neuronal surface receptors such as myasthenia gravis or Lambert Eaton myasthenic syndrome. J. Clin. Apheresis 31:368-374, 2016. © 2015 Wiley Periodicals, Inc.


Assuntos
Síndromes da Dor Regional Complexa/terapia , Troca Plasmática/métodos , Disautonomias Primárias/terapia , Adolescente , Autoanticorpos/sangue , Feminino , Humanos , Receptor Muscarínico M2/imunologia , Receptores Adrenérgicos beta 2/imunologia , Receptores Nicotínicos/imunologia
4.
J Heart Valve Dis ; 24(4): 457-64, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26897816

RESUMO

BACKGROUND AND AIM OF THE STUDY: Managing patients with asymptomatic severe aortic stenosis (AS) remains a major challenge. Myocardial as well as cardiocirculatory reserve have been hypothesized to predict outcome in patients with asymptomatic AS. METHODS: A total of 48 patients (indexed aortic valve area 0.39 +/- 0.12 cm2/m2; ejection fraction (EF) 67 +/- 7%) underwent spiroergometry and dobutamine stress echocardiography. Death or valve surgery served as a combined endpoint for follow up. RESULTS: Thirty-seven patients reached the endpoint after a mean of 756 days (range: 100-2146 days). Age- and gender-corrected univariate Cox proportional analysis revealed the presence of mild obstructive lung disease, stroke work loss (SWL), end-systolic diameter index, and E/Flow propagation velocity as the best predictive clinical, valvular, cardiostructural, and left ventricular filling pressure parameters, respectively. After inclusion of these parameters into a baseline multivariable Cox proportional hazard model, SWL (HR 1.21 per rise of 1 unit, CI 1.08-1.35, p = 0.0005) and female gender (HR 3.37, CI 1.50-7.59, p = 0.0044) were independently predictive. Similarly, the best-performing myocardial parameter, EF after dobutamine, was independently predictive (HR 0.75 per 5 units, CI 0.57-0.99, p = 0.035) after inclusion. The best-performing exercise capacity parameter, Watt(max), was of borderline significance (HR 0.93 per 5 units, CI 0.86-1.00, p = 0.0505). For each parameter, cut-off values were determined by time-dependent receiver-operator characteristics. The Kaplan-Meier curves of the patients above versus below the cut-offs differed significantly for SWL (p = 0.001), Wattm (p = 0.001), and gender (p = 0.013). CONCLUSION: Besides SWL and female gender, the EF after dobutamine as well as highest exercise stress intensity reached are helpful in determining the prognosis of asymptomatic patients with moderate-severe AS.


Assuntos
Estenose da Valva Aórtica/diagnóstico , Valva Aórtica/fisiopatologia , Circulação Coronária , Contração Miocárdica , Volume Sistólico , Função Ventricular Esquerda , Idoso , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/cirurgia , Área Sob a Curva , Doenças Assintomáticas , Cardiotônicos/administração & dosagem , Dobutamina/administração & dosagem , Ecocardiografia sob Estresse , Teste de Esforço , Tolerância ao Exercício , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Prospectivos , Curva ROC , Fatores de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Fatores de Tempo
5.
Cardiovasc Ultrasound ; 13: 13, 2015 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-25889047

RESUMO

BACKGROUND: Participation of amateur runners in endurance races continues to increase. Previous studies of marathon runners have raised concerns about exercise-induced myocardial and renal dysfunction and damage. In our pooled analysis, we aimed to characterize changes of cardiac and renal function after marathon running in a large cohort of mostly elderly amateur marathon runners. METHODS: A total of 167 participants of the Berlin-Marathon (female n = 89, male n = 78; age = 50.3 ± 11.4 years) were included and cardiac and renal function was analyzed prior to, immediately after and 2 weeks following the race by echocardiography and blood tests (including cardiac troponin T, NT-proBNP and cystatin C). RESULTS: Among the runners, 58% exhibited a significant increase in cardiac biomarkers after completion of the marathon. Overall, the changes in echocardiographic parameters for systolic or diastolic left and right ventricular function did not indicate relevant myocardial dysfunction. Notably, 30% of all participants showed >25% decrease in cystatin C-estimated glomerular filtration rate (GFR) from baseline directly after the marathon; in 8%, we observed a decline of more than 50%. All cardiac and renal parameters returned to baseline ranges within 2 weeks after the marathon. CONCLUSIONS: The increase in cardiac biomarkers after completing a marathon was not accompanied by relevant cardiac dysfunction as assessed by echocardiography. After the race, a high proportion of runners experienced a decrease in cystatin C-estimated GFR, which is suggestive of transient, exercise-related alteration of renal function. However, we did not observe persistent detrimental effects on renal function.


Assuntos
Ecocardiografia/métodos , Ventrículos do Coração/diagnóstico por imagem , Rim/fisiologia , Resistência Física/fisiologia , Corrida/fisiologia , Função Ventricular Esquerda/fisiologia , Idoso , Desempenho Atlético/fisiologia , Estudos de Coortes , Testes de Função Cardíaca , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Aptidão Física/fisiologia , Adulto Jovem
6.
Mol Cell Biochem ; 393(1-2): 177-80, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24744110

RESUMO

Autoantibodies (AABs) against the second extracellular loop of the beta1-receptor (beta1(II)-AABs) are found as a pathogenic driver in patients with idiopathic dilated cardiomyopathy, Chagas cardiomyopathy, peripartum cardiomyopathy, and myocarditis, and have been increasingly seen as a treatment target. We recently identified an aptamer (single short DNA strand) that specifically binds and neutralizes beta1(II)-AABs. Via application of this aptamer, a new treatment strategy for diseases associated with the cardio-pathogenic beta1(II)-AABs could be developed. Spontaneously hypertensive rats (SHR) positive for beta1(II)-AABs were treated five times at weekly intervals (bolus application of 2 mg/kg body weight followed by an infusion of the same amount over 20 min). SHR responded to aptamer treatment with a strong reduction in the cardio-pathogenic beta1(II)-AABs. The AABs did not substantially return within the study period. No signs for aptamer toxicity were observed by visual examination of the heart, liver, and kidney, or by measurement of plasma CK, ALT, and creatinine. The aptamer's potential for beta1(II)-AAB neutralization and consequently for cardiomyopathy treatment has been shown for the first time in vivo.


Assuntos
Aptâmeros de Nucleotídeos/administração & dosagem , Autoanticorpos/efeitos dos fármacos , Cardiomiopatia Dilatada/genética , Receptores Adrenérgicos beta 1/genética , Animais , Aptâmeros de Nucleotídeos/genética , Autoanticorpos/genética , Cardiomiopatia Dilatada/tratamento farmacológico , Cardiomiopatia Dilatada/patologia , Humanos , Ratos , Ratos Endogâmicos SHR/genética , Receptores Adrenérgicos beta 1/imunologia
7.
Circ Res ; 109(9): 986-92, 2011 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-21868696

RESUMO

RATIONALE: Autoantibodies directed against the beta1-adrenoceptor (beta1-AABs) have been proposed to drive the pathogenesis of idiopathic dilated cardiomyoparthy (DCM), Chagas' cardiomyopathy, and peripartum cardiomyopathy. For disease treatment, aptamers that bind and neutralize beta1-AABs could be significant. OBJECTIVE: We determined whether oligonucleotide-aptamers, selected to target human beta1-AABs directed against the second extracellular loop of the beta1-AAB, can neutralize these AABs and modulate their function in vitro. METHODS AND RESULTS: Using Monolex technology, we identified an ssDNA aptamer that targets human beta1-AABs. The neutralization potential of this aptamer against beta1-AABs isolated from patients with DCM, Chagas' cardiomyopathy, and peripartum cardiomyopathy was analyzed using cultured neonatal rat cardiomyocytes by monitoring beta1-AAB induced cell toxicity and chronotropic cell responses. Aptamer addition reduced beta1-AAB induced cell toxicity and neutralized chonotropic beta1-AAB function in a dose-dependent manner. In the presence of aptamer neutralized beta1-AABs, cells remained fully responsive to agonists and antagonists, such as isoprenaline and bisoprolol. Both aptamer pretreated with a complementary (antisense) aptamer and a control scrambled-sequence aptamer were ineffective at beta1-AAB neutralization. Beta1-AABs directed against the first extracellular loop of the beta1-receptor and AABs directed against other G-protein coupled receptors were not affected by the selected aptamer. CONCLUSIONS: A specific aptamer that can neutralize cardiomyopathy associated human beta1-AABs in vitro has been identified and characterized, providing a framework for future in vivo testing of this treatment option in animal experiments.


Assuntos
Aptâmeros de Nucleotídeos/farmacologia , Autoanticorpos/efeitos dos fármacos , Cardiomiopatia Dilatada/imunologia , Cardiomiopatia Chagásica/imunologia , Receptores Adrenérgicos beta 1/imunologia , Agonistas de Receptores Adrenérgicos beta 1/farmacologia , Antagonistas de Receptores Adrenérgicos beta 1/farmacologia , Animais , Especificidade de Anticorpos , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Autoanticorpos/imunologia , Autoanticorpos/metabolismo , Bisoprolol/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Técnicas In Vitro , Isoproterenol/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/imunologia , Miócitos Cardíacos/metabolismo , Ratos , Receptores Adrenérgicos beta 1/metabolismo
8.
Clin Chem Lab Med ; 51(2): 271-94, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23045386

RESUMO

Chagas disease, caused by Trypanosoma cruzi infection, is ranked as the most serious parasitic disease in Latin America and has huge potential to become a worldwide problem, due to increasing migration, and international tourism, as well as infectant transfer by blood contact and transfusion, intrauterine transfer, and organ transplantation. Nearly 30% of chronically-infected patients become symptomatic, often with a latency of 10-30 years, developing life-threatening complications. Of those, nearly 90% develop Chagas heart disease, while the others manifest gastrointestinal disease and neuronal disorders. Besides interrupting the infection cycle and chemo therapeutic infectant elimination, starting therapy early in symptomatic patients is important for counteracting the disease. This would be essentially supported by optimized patient management, involving risk assessment, early diagnosis and monitoring of the disease and its treatment. From economic and logistic viewpoints, the tools of laboratory medicine should be especially able to guarantee this. After summarizing the basics of chronic Chagas disease, such as the epidemiological data, the pathogenetic mechanisms thought to drive symptomatic Chagas disease and also treatment options, we present tools of laboratory medicine that address patient diagnosis, risk assessment for becoming symptomatic and guidance, focusing on autoantibody estimation for risk assessment and heart marker measurement for patient guidance. In addition, increases in levels of inflammation and oxidative stress markers in chronic Chagas disease are discussed.


Assuntos
Doença de Chagas/diagnóstico , Doença de Chagas/terapia , Doença de Chagas/parasitologia , Doença Crônica , Humanos , Trypanosoma cruzi/isolamento & purificação
9.
Heart Fail Rev ; 17(1): 45-64, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21165698

RESUMO

Chagas' disease, caused by Trypanosoma cruzi infection, is ranked as the most serious parasitic disease in Latin America. Nearly 30% of infected patients develop life-threatening complications, and with a latency of 10-30 years, mostly Chagas' heart disease which is currently the major cause of morbidity and mortality in Latin America, enormously burdening economic resources and dramatically affecting patients' social and labor situations. Because of increasing migration, international tourism and parasite transfer by blood contact, intrauterine transfer and organ transplantation, Chagas' heart disease could potentially become a worldwide problem. To raise awareness of this problem, we reflect on the epidemiology and etiopathology of Chagas' disease, particularly Chagas' heart disease. To counteract Chagas' heart disease, in addition to the general interruption of the infection cycle and chemotherapeutic elimination of the infection agent, early and effective causal or symptomatic therapies would be indispensable. Prerequisites for this are improved knowledge of the pathogenesis and optimized patient management. From economic and logistics viewpoints, this last prerequisite should be performed using laboratory medicine tools. Consequently, we first summarize the mechanisms that have been suggested as driving Chagas' heart disease, mainly those associated with the presence of autoantibodies against G-protein-coupled receptors; secondly, we indicate new treatment strategies involving autoantibody apheresis and in vivo autoantibody neutralization; thirdly, we present laboratory medicine tools such as autoantibody estimation and heart marker measurement, proposed for diagnosis, risk assessment and patient guidance and lastly, we critically reflect upon the increase in inflammation and oxidative stress markers in Chagas' heart disease.


Assuntos
Cardiomiopatia Chagásica/epidemiologia , Cardiomiopatia Chagásica/tratamento farmacológico , Cardiomiopatia Chagásica/etiologia , Cardiomiopatia Chagásica/parasitologia , Saúde Global , Humanos , Tripanossomicidas/uso terapêutico , Trypanosoma cruzi
10.
Circ J ; 76(10): 2449-55, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22850243

RESUMO

BACKGROUND: Application of immunoapheresis to eliminate pathogenic autoantibodies targeting the second extracellular loop of the ß1-receptor (ß1-AABs) is currently investigated in patients with cardiomyopathy. Aptamers (single short DNA or RNA strands) are a new class of molecules that bind to a specific target molecule. This property qualifies aptamers for potential use in the apheresis technique. We recently identified an aptamer that specifically binds to ß1-AABs, so in the present study we tested whether this aptamer could be used as a binder to prepare an apheresis column suitable for clearing ß1-AABs from rat's blood. METHODS AND RESULTS: An apheresis column was designed containing the ß1-AAB-targeting-aptamer coupled to sepharose. As tested in vitro, this column (1) binds ß1-AABs highly specifically without marked interference with common IgGs, (2) has a capacity for clearing of approximately 1L of ß1-AAB-positive serum and (3) can be completely regenerated for subsequent use. Using the column for extracorporeal apheresis of spontaneously hypertensive rats (SHR) positive for both ß1-AABs and muscarinic 2-receptor autoantibodies (M2-AABs), only ß1-AABs were removed. In a follow-up of 9 weeks, recurrence of ß1-AABs in the blood of SHR could not be detected. CONCLUSIONS: For the first time, a newly designed apheresis column with a ß1-AAB specific aptamer as a binder was successfully used to eliminate ß1-AABs from SHR blood.


Assuntos
Aptâmeros de Nucleotídeos/química , Autoanticorpos , Remoção de Componentes Sanguíneos/instrumentação , Remoção de Componentes Sanguíneos/métodos , Cardiomiopatias/terapia , Imunoadsorventes/química , Receptores Adrenérgicos beta 1 , Animais , Aptâmeros de Nucleotídeos/imunologia , Cardiomiopatias/sangue , Cardiomiopatias/imunologia , Imunoadsorventes/imunologia , Estrutura Secundária de Proteína , Coelhos , Ratos Endogâmicos SHR , Receptor Muscarínico M2/sangue , Receptor Muscarínico M2/imunologia
11.
J Heart Valve Dis ; 21(5): 576-83, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23167221

RESUMO

BACKGROUND AND AIM OF THE STUDY: Patients with moderate-severe aortic stenosis (AS) who maintain that they have no symptoms pose a decision-making dilemma. In order to determine whether or not preoperative symptoms were related to outcomes in these patients, results were compared after aortic valve replacement (AVR) in asymptomatic and symptomatic AS patients with a preserved left ventricular ejection fraction (LVEF). METHODS: Twenty asymptomatic and 18 symptomatic AS patients were investigated retrospectively, with clinical and echocardiographic studies being performed before and at 610 +/- 409 days after AVR. The patients' cardiopulmonary function was monitored using spiroergometry. RESULTS: Symptomatic AS patients improved their exercise tolerance after surgery more than asymptomatic patients, although exercise tolerance and LVEF remained lower in symptomatic patients. On comparing all postoperative objective changes between the groups, a difference was observed only for aortic valve area index. Improvements in left ventricular structure, diastolic function, and filling pressures after AVR were similar in both groups. Systolic function, as assessed by tissue Doppler, was improved only in the symptomatic group. Regression analyses identified preoperative exercise tolerance as the strongest independent determinant of postoperative functional outcome. The postoperative LVEF was independently predicted by the preoperative LVEF and exercise tolerance. CONCLUSION: Asymptomatic patients with moderate-severe AS and preserved systolic function exhibited similar improvements in cardiac remodeling, diastolic function, and filling pressures following AVR, compared to symptomatic patients. Differences in exercise tolerance and systolic function observed preoperatively between these groups were decreased after AVR.


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Idoso , Estenose da Valva Aórtica/diagnóstico por imagem , Ecocardiografia , Tolerância ao Exercício , Feminino , Testes de Função Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
12.
Cardiovasc Ultrasound ; 10: 6, 2012 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-22357096

RESUMO

BACKGROUND: Our study compares new single beat 3D echocardiography (sb3DE) to cardiovascular magnetic resonance imaging (CMR) for the measurement of right ventricular (RV) dimension and function immediately after a 30 km run. This is to validate sb3DE against the "gold standard" CMR and to bring new insights into acute changes of RV dimension and function after endurance exercise. METHODS: 21 non-elite male marathon runners were examined by sb3DE (Siemens ACUSON SC2000, matrix transducer 4Z1c, volume rates 10-29/s), CMR (Siemens Magnetom Avanto, 1,5 Tesla) and blood tests before and immediately after each athlete ran 30 km. The runners were not allowed to rehydrate after the race. The order of sb3DE and CMR examination was randomized. RESULTS: Sb3DE for the acquisition of RV dimension and function was feasible in all subjects. The decrease in mean body weight and the significant increase in hematocrit indicated dehydration. RV dimensions measured by CMR were consistently larger than measured by sb3DE.Neither sb3DE nor CMR showed a significant difference in the RV ejection fraction before and after exercise. CMR demonstrated a significant decrease in RV dimensions. Measured by sb3DE, this decrease of RV volumes was not significant. CONCLUSION: First, both methods agree well in the acquisition of systolic RV function. The dimensions of the RV measured by CMR are larger than measured by sb3DE. After exercise, the RV volumes decrease significantly when measured by CMR compared to baseline.Second, endurance exercise seems not to induce acute RV dysfunction in athletes without rehydration.


Assuntos
Ecocardiografia Tridimensional , Ventrículos do Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética , Função Ventricular Direita , Estudos de Viabilidade , Humanos , Masculino , Resistência Física/fisiologia , Corrida/fisiologia
13.
Anal Chem ; 83(9): 3379-85, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21413805

RESUMO

Microbead-based assays have evolved into powerful tools for the multiplex detection of biomolecules. Analytes are captured by DNA or protein capture molecules which are coupled on microbead surfaces. A homogeneous carboxylation of microbeads is essential for the optimal and reproducible coupling of capture molecules and thus a prerequisite for an optimal multiplex microbead-based assay performance. We developed a simple fluorescence dye adsorption assay for the description of microbead carboxylation and for the prediction of coupling successes of capture molecules. Using the fluorescence dye SYTO-62 it is possible to quantify the degree of carboxylation of poly(methyl methacrylate) (PMMA) microbeads within 1 h in a multiplex format by fluorescence microscopy or flow cytometry. Compared to conventional bulk assays which only provide an average degree of carboxylation the main advantage of the SYTO-62 assay is the single microbead analysis and therefore the description of the qualitative distribution of carboxylation in microbead populations. The SYTO-62 assay is sensitive enough to even determine weak carboxylation. Also, the quality of microbeads can be evaluated. To our knowledge this is the first report which applies a reversible noncovalent fluorescent dye adsorption assay to quantify the degree of carboxylation on surfaces.


Assuntos
Dióxido de Carbono/análise , Corantes Fluorescentes/química , Microesferas , Polimetil Metacrilato/química , Adsorção , Dióxido de Carbono/química , Citometria de Fluxo , Concentração de Íons de Hidrogênio , Sondas de Oligonucleotídeos/química , Controle de Qualidade , Estreptavidina/química , Propriedades de Superfície , Fatores de Tempo
14.
Clin Lab ; 56(1-2): 51-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20380359

RESUMO

BACKGROUND: As shown on the basis of highly sensitive assays, cardiac troponin release is now observed after physiological heart stress and in mild heart pathologies: both are [corrected] considered unrelated to the irreversible cardiac alteration that is typically the source of release. Transitory cardiac membrane leakage was suggested as the basis. In our view, mild inflammation may drive this type of cardiac troponin release. To verify this hypothesis, marathon runners who demonstrated post-run inflammation were used as a model to correlate cTnT release and inflammation intensity. METHODS: In 78 male marathon runners who participated in the BERLIN-MARATHON 2006, cardiac troponin T (cTnT) was monitored [corrected] at three time points (pre-race, post-race, and after two weeks of rest). [corrected] Measurements were done with the highly sensitive assay (hs cTnT assay) and the conventional fourth-generation cTnT assay for comparison. Concurrently, [corrected] the inflammation markers (leukocyte and neutrophil counts, CRP, IL-6) were measured. RESULTS: Pre-race, the fourth-generation assay failed to demonstrate cTnT positivity (> test specific LLD). In contrast, with the [corrected] use of the highly sensitive assay, 28% of the participants were positive for cTnT (> LLD of hs cTnT assay). Post-race, cTnT as measured with the fourth-generation assay was observed to be detectable in 43% of the runners (> LLD = 99(th) percentile cut off), but all runners had detectable cTnT values (> LLD) when measured with the highly sensitive assay. Even in 94% of these cTnT-positive runners, the value exceeded the 99(th) percentile cut off determined for the highly sensitive assay (13 ng/L). cTnT release correlated significantly with inflammation intensity. Faster runners demonstrated significantly stronger cTnT releases and inflammation signs. CONCLUSIONS: As demonstrated after physiological heart stress such as marathon running, transitory inflammation is evidently one of the events contributing to the cardiac troponin release under conditions suggested as unrelated to irreversible cardiac alteration.


Assuntos
Traumatismos em Atletas/sangue , Inflamação/etiologia , Corrida/fisiologia , Troponina T/sangue , Asma/sangue , Asma/epidemiologia , Atletas , Pressão Sanguínea , Frequência Cardíaca , Humanos , Hipertensão/sangue , Hipertensão/epidemiologia , Inflamação/sangue , Masculino , Sensibilidade e Especificidade
15.
Auto Immun Highlights ; 11(1): 13, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32977857

RESUMO

BACKGROUND: For prostate cancer, signaling pathways induced by over-boarding stimulation of G-protein coupled receptors (GPCR) such as the endothelin, α1- and ß-adrenergic, muscarinic and angiotensin 1 receptors were accused to support the carcinogenesis. However, excessive receptor stimulation by physiological receptor ligands is minimized by a control system that induces receptor sensitization and down-regulation. This system is missing when so-called "functional autoantibodies" bind to the GPCR (GPCR-AAB). If GPCR-AAB were found in patients with prostate cancer, uncontrolled GPCR stimulation could make these autoantibodies an additional supporter in prostate cancer. METHODS: Using the bioassay of spontaneously beating cultured rat neonatal cardiomyocytes, GPCR-AAB were identified, quantified and characterized in the serum of 25 patients (aged 56-78 years, median 70 years) with prostate cancer compared to 10 male patients (aged 48-82 years, median 64) with urinary stone disorders (controls). RESULTS: Of the cancer patients, 24 (96%) and 17 (68%), respectively, carried autoantibodies directed against the α1-adrenergic receptor (α1-AAB) and endothelin receptor A (ETA-AAB). No patient was negative for both GPCR-AAB. In contrast, ETA-AAB and α1-AAB were absent in all (100%) and 9 (90%) of the 10 control patients, respectively. While α1-AAB targeted a specific epitope of the first extracellular loop of the α1-adrenergic receptor subtype A, an epitope of the second extracellular loop of the ETA receptor was identified as a target of ETA-AAB. As demonstrated in vitro, the functional activity of both autoantibodies found in prostate cancer can be neutralized by the aptamer BC007. CONCLUSIONS: We hypothesized that α1-AAB and ETA-AAB, which are highly present in prostate cancer patients, could by their functional activity support carcinogenesis by excessive receptor stimulation. The in vitro demonstrated neutralization of α1- and ETA-AAB by the aptamer BC007 could open the door to complement the treatments already available for prostate cancer.

16.
ESC Heart Fail ; 7(3): 844-855, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32212256

RESUMO

AIMS: Aptamer BC 007, a 15-mer single-strand DNA oligonucleotide (5'-GGTTGGTGTGGTTGG-3'), was developed to neutralize functional autoantibodies that bind to the extracellular domains of G protein-coupled receptors (GPCR-AAB), leading to the modulation of receptor-mediated signalling cascades that induce pathophysiological states. Among the GPCR-AAB, there are those directed against the ß1-adrenergic receptor (ß1-AAB) that are highly present in patients with dilated cardiomyopathy (DCM) and are increasingly accepted as disease drivers. Using Doberman Pinschers (DP) with DCM, which possess similarities with human DCM among these ß1-AAB positivity for that the disease-driving role in DP DCM was demonstrated, the safety of BC 007, efficacy for neutralizing ß1-AAB, and the DP's outcome were investigated. METHODS AND RESULTS: Fourteen client-owned ß1-AAB-positive DP with electrocardiographically and echocardiographically indicated DCM were treated with BC 007. For controlling, two groups were created: 14 ß1-AAB-positive DP with DCM not treated with BC 007 (Control 1) and 14 DP with DCM closely matched to the BC 007-treated DP (Control 2), retrospectively selected from the institutional database of DP. After treatment, DP were monitored both echocardiographically, and for ß1-AAB, and survival curves were calculated. Based on clinical and laboratory examination, no adverse effects associated with BC 007 treatment were observed during the study. Forty-eight hours after treatment, the DP's blood was free of ß1-AAB, which led to a reduction or stabilization of left ventricular end-systolic volume (ESVI) during ß1-AAB free time in 10 of the treated DP. In one DP, where ß1-AAB returned after 3 months and ESVI worsened again, a second BC 007 treatment after 9 months again cleared the blood from ß1-AAB and improved the ESVI. Compared with the controls, DP treated with BC 007 showed a significantly longer survival time [572 days, interquartile range (IQR) 442-840 days] vs. Control group 1 (266 days, IQR 97-438 days; logrank: P = 0.009) and Control group 2 (229 days, IQR 174-319 days; logrank: P = 0.012). CONCLUSIONS: Treatment with BC 007 for ß1-AAB neutralization was safe, resulted in a long-lasting reduction of ß1-AAB combined with improved cardiac function and prolonged the survival of DP with DCM. Using a natural large animal model of DCM considered superior to small animal models of immunization-induced cardiomyopathy, combined with a study design comparable with clinical trials, we believe that our results provide the basis for optimism that treatment with BC 007 might also be effective in human patients with DCM.


Assuntos
Cardiomiopatias , Cardiomiopatia Dilatada , Animais , Autoanticorpos , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/tratamento farmacológico , Modelos Animais de Doenças , Cães , Humanos , Estudos Retrospectivos
17.
Clin Drug Investig ; 40(5): 433-447, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32222912

RESUMO

BACKGROUND AND OBJECTIVE: BC 007 is a substance with a novel and innovative mode of action for the first-time causal treatment of chronic heart failure, associated with the occurrence of autoantibodies against the ß1-adrenoceptor, and other diseases of mostly the heart and vascular system, being accompanied by the occurrence of functionally active agonistic autoantibodies against G-protein-coupled receptors (fGPCR-AAb). The proposed mechanism of action of BC 007 is the neutralisation of these pathogenic autoantibodies which stimulate the respective receptor. To evaluate the safety, tolerability, pharmacokinetics and mode of action of BC 007, single intravenous infusions of increasing concentration were given to healthy young males and healthy elderly autoantibody-negative and autoantibody-positive participants of both sexes. METHODS: This study was subdivided into three parts. Part A was a single-centre, randomised, double-blind, placebo-controlled safety and tolerability study including healthy young male autoantibody-negative Whites (N = 23) and Asians (N = 1), testing doses of 15, 50 and 150 mg BC 007 (Cohorts 1-3) and elderly male and female Whites (N = 8), testing a dose of 150 mg BC 007 (Cohort 4), randomly assigned in a 3:1 ratio to BC 007 or placebo. Open-label Part B included fGPCR-AAb-positive subjects (50 and 150 mg BC 007, Cohorts 1 and 2, respectively). Open-label Part C included fGPCR-AAb-positive subjects for testing doses of 300, 450, 750, 1350 mg and 1900 mg BC 007. Lower doses were either given as an infusion or divided into a bolus plus infusion up to a dose of 300 mg followed by a constant bolus of 150 mg up to a dose of 750 mg, while at doses of 1350 mg and 1900 mg it was a slow infusion with a constant infusion rate. Infusion times increased with increasing dose from 20 min (15, 50 or 150 mg) to 40 min (300, 450 or 750 mg), 75 min (1350 mg) and 105 min (1900 mg). RESULTS: The mean observed BC 007 area under the concentration-time curve (AUC0-24) increased with increasing dose in a dose proportional manner (slope estimate of 1.039). No serious adverse events were observed. Drug-related adverse events were predominantly the expected mild-to-moderate increase in bleeding time (aPTT), beginning with a dose of 50 mg, which paralleled the infusion and returned to normal shortly after infusion. fGPCR-AAb neutralisation efficiency increased with increasing dose and was achieved for all subjects in the last cohort. CONCLUSION: BC 007 is demonstrated to be safe and well tolerated. BC 007 neutralised fGPCR-AAb, showing a trend for a dose-response relationship in elderly healthy but fGPCR-AAb-positive subjects. CLINICALTRIALS. GOV REGISTRATION NUMBER: NCT02955420.


Assuntos
Autoanticorpos/imunologia , Insuficiência Cardíaca/tratamento farmacológico , Receptores Acoplados a Proteínas G/imunologia , Adulto , Idoso , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , Placebos , Adulto Jovem
18.
Circulation ; 117(12): 1563-73, 2008 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-18332268

RESUMO

BACKGROUND: The hallmarks of diabetic cardiomyopathy are cardiac oxidative stress, intramyocardial inflammation, cardiac fibrosis, and cardiac apoptosis. Given the antioxidative, antiinflammatory, and antiapoptotic potential of high-density lipoprotein (HDL), we evaluated the hypothesis that increased HDL via gene transfer (GT) with human apolipoprotein (apo) A-I, the principal apolipoprotein of HDL, may reduce the development of diabetic cardiomyopathy. METHODS AND RESULTS: Intravenous GT with 3x10(12) particles/kg of the E1E3E4-deleted vector Ad.hapoA-I, expressing human apoA-I, or Ad.Null, containing no expression cassette, was performed 5 days after streptozotocin (STZ) injection. Six weeks after apoA-I GT, HDL cholesterol levels were increased by 1.6-fold (P<0.001) compared with diabetic controls injected with the Ad.Null vector (STZ-Ad.Null). ApoA-I GT and HDL improved LV contractility in vivo and cardiomyocyte contractility ex vivo, respectively. Moreover, apoA-I GT was associated with decreased cardiac oxidative stress and reduced intramyocardial inflammation. In addition, compared with STZ-Ad.Null rats, cardiac fibrosis and glycogen accumulation were reduced by 1.7-fold and 3.1-fold, respectively (P<0.05). Caspase 3/7 activity was decreased 1.2-fold (P<0.05), and the ratio of Bcl-2 to Bax was upregulated 1.9-fold (P<0.005), translating to 2.1-fold (P<0.05) reduced total number of cardiomyocytes with apoptotic characteristics and 3.0-fold (P<0.005) reduced damaged endothelial cells compared with STZ-Ad.Null rats. HDL supplementation ex vivo reduced hyperglycemia-induced cardiomyocyte apoptosis by 3.4-fold (P<0.005). The apoA-I GT-mediated protection was associated with a 1.6-, 1.6-, and 2.4-fold induction of diabetes-downregulated phospho to Akt, endothelial nitric oxide synthase, and glycogen synthase kinase ratio, respectively (P<0.005). CONCLUSIONS: ApoA-I GT reduced the development of streptozotocin-induced diabetic cardiomyopathy.


Assuntos
Apolipoproteína A-I/administração & dosagem , Cardiomiopatias/prevenção & controle , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/terapia , Terapia Genética/métodos , Animais , Apolipoproteína A-I/genética , Cardiomiopatias/terapia , Vetores Genéticos/genética , Humanos , Lipídeos/sangue , Lipoproteínas HDL , Ratos , Ratos Sprague-Dawley , Estreptozocina , Substâncias Reativas com Ácido Tiobarbitúrico/análise
19.
Anal Bioanal Chem ; 393(5): 1499-504, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18791707

RESUMO

In terms of testing, modern laboratory medicine can be divided into centralized testing in central laboratories and point-of-care testing (POCT). Centralized laboratory medicine offers high-quality results, as guaranteed by the use of quality management programs and the excellence of the staff. POCT is performed by clinical staff, and so such testing has moved back closer to the patient. POCT has the advantage of shortening the turnaround time, which potentially benefits the patient. However, the clinical laboratory testing expertise of clinical staff is limited. Consequently, when deciding which components of laboratory testing must be conducted in central laboratories and which components as POCT (in relation to quality and timeliness), it will be medical necessity, medical utility, technological capabilities and costs that will have to be ascertained. Provided adequate quality can be guaranteed, POCT is preferable, considering its timeliness, when testing vital parameters. It is also preferred when the central laboratory cannot guarantee the delivery of results of short turn-around-time (STAT) markers within 60 or (even better) 30 min. POCT should not replace centralized medical laboratory testing in general, but it should be used in cases where positive effects on patient care have been clearly demonstrated.


Assuntos
Sistemas de Informação em Laboratório Clínico , Laboratórios Hospitalares , Sistemas Automatizados de Assistência Junto ao Leito/normas , Humanos , Controle de Qualidade , Fatores de Tempo
20.
Methods Mol Biol ; 1955: 247-261, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30868533

RESUMO

Autoantibodies directed against G-protein-coupled receptors (GPCR-AAB), an autoantibody type discovered in the 1970s, affect functionally their targets and are therefore called functional autoantibodies. GPCR-AAB are increasingly accepted as the origin or amplifier of various diseases. Here, we describe the present "gold standard" for measurement of GPCR-AAB in human blood. This bioassay monitors the chronotropic activity of GPCR-AAB by recording the spontaneous beating of cultured neonatal rat cardiomyocytes. The construction of this bioassay and its procedure and standardization for GPCR-AAB measurement are described in detail and also include the application of the bioassay for GPCR-AAB differentiation related to first the targeted receptors and IgG subclasses carrying the GPCR-AAB and second the extracellular receptor-binding site and specific epitopes targeted by the GPCR-AAB.


Assuntos
Autoanticorpos/imunologia , Doença de Chagas/imunologia , Receptores Acoplados a Proteínas G/imunologia , Animais , Autoanticorpos/sangue , Células Cultivadas , Doença de Chagas/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Mapeamento de Epitopos/métodos , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Camundongos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/imunologia , Ratos
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