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1.
Interv Med Appl Sci ; 11(3): 187-192, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36343288

RESUMO

Introduction: Many coronary anastomotic devices have been designed to replace manual stitching in coronary surgery; however, interestingly, none of them became widespread. Our aim was to work out an easy and fast endoluminal vessel-to-vessel stent bridge distal anastomotic technique. Materials and methods: Ten coronary arteries of eight fresh human hearts were used in this study. The anastomosis was performed with the implantation of a graft vessel into the lumen of the coronary artery by performing stent fixation. The technique is described and photo documented in detail. The durability and the conductibility of the anastomosis were examined with intraluminal endoscopy, functional streaming test, and a coloring of the vessels. Results: The anastomosis had great results in all cases. Obstruction, dissection, or dislocation of the vessels was not observable. Conclusions: This study confirmed the ex-vivo feasibility of the described technique. This method can be an easy, fast, and reliable method applied in the endoscopic distal coronary artery anastomosis surgery. The development of stents adapted to this method and the in-vivo testing of this technique are necessary for the future.

2.
Thorac Cardiovasc Surg ; 63(3): 238-42, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25207488

RESUMO

BACKGROUND: An increasing number of experimental beating heart animal studies describe simple transapical mitral valve repairs based on the direct endoscopic visualization of the left ventricle. The aim of our human cadaveric study was to develop a method for more complex transapical endoscopic procedures by on-pump heart operations. MATERIALS AND METHODS: After preparation of 20 human fresh cadavers, a standard left anterolateral minithoracotomy was performed in the fifth intercostal space and the pericardium was entered. A rigid 0 degree endoscope and the instruments were introduced through a silicon apical port. To restore the natural form of the left heart, CO2 was insufflated. To test the mitral valve competence, the left ventricle was pressure-injected with saline after each step. After transecting the chords of the A2 segment of the anterior mitral leaflet before the experimental mitral valve repair, the tendinous chord was replaced using an especially designed clip chord. The second part of the experiment consisted of a segmental excision of the P2 segment of the posterior mitral leaflet followed by a standard valvuloplasty and suture annuloplasty. RESULTS: With the help of the described transapical endoscopic mitral valve repair technique, we gained direct visual information of the coaptation line of the mitral leaflets as well as the anatomy and function of the subvalvular apparatus. Using intracardiac imaging, we could perform successful transapical complex mitral repair in each case. CONCLUSION: The minimally invasive transapical endoscopic method has the potential to offer advantages for on-pump mitral valve repair procedures even in complex mitral valve repair cases.


Assuntos
Anuloplastia da Valva Cardíaca/métodos , Endoscopia/métodos , Valva Mitral/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/anatomia & histologia , Toracotomia
3.
Curr Pharm Des ; 21(8): 965-76, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25354187

RESUMO

Adenosine is a ubiquitous, endogenous purine involved in a variety of physiological and pathophysiological regulatory mechanisms. Adenosine has been proposed as an endogenous antiarrhythmic substance to prevent hypoxia/ischemia-induced arrhythmias. Adenosine (and its precursor, ATP) has been used in the therapy of various cardiac arrhythmias over the past six decades. Its primary indication is treatment of paroxysmal supraventricular tachycardia, but it can be effective in other forms of supraventricular and ventricular arrhythmias, like sinus node reentry based tachycardia, triggered atrial tachycardia, atrioventricular nodal reentry tachycardia, or ventricular tachycardia based on a cAMP-mediated triggered activity. The main advantage is the rapid onset and the short half life (1- 10 sec). Adenosine exerts its antiarrhythmic actions by activation of A1 adenosine receptors located in the sinoatrial and atrioventricular nodes, as well as in activated ventricular myocardium. However, adenosine can also elicit A2A, A2B and A3 adenosine receptor-mediated global side reactions (flushing, dyspnea, chest discomfort), but it may display also proarrhythmic actions mediated by primarily A1 adenosine receptors (e.g. bradyarrhythmia or atrial fibrillation). To avoid the non-specific global adverse reactions, A1 adenosine receptor- selective full agonists (tecadenoson, selodenoson, trabodenoson) have been developed, which agents are currently under clinical trial. During long-term administration with orthosteric agonists, adenosine receptors can be internalized and desensitized. To avoid desensitization, proarrhythmic actions, or global adverse reactions, partial A1 adenosine receptor agonists, like CVT-2759, were developed. In addition, the pharmacologically "silent" site- and event specific adenosinergic drugs, such as adenosine regulating agents and allosteric modulators, might provide attractive opportunity to increase the effectiveness of beneficial actions of adenosine and avoid the adverse reactions.


Assuntos
Adenosina/farmacologia , Antiarrítmicos/farmacologia , Arritmias Cardíacas/tratamento farmacológico , Adenosina/fisiologia , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/fisiopatologia , Sistema Cardiovascular/fisiopatologia , Sistema de Condução Cardíaco/efeitos dos fármacos , Sistema de Condução Cardíaco/fisiologia , Humanos , Receptores Purinérgicos P1/efeitos dos fármacos , Receptores Purinérgicos P1/fisiologia
4.
Thorac Cardiovasc Surg ; 63(3): 231-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24420678

RESUMO

BACKGROUND: We compared the aortic, left atrial, and apical approaches to visualize the mitral valve with the goal to investigate the endoscopic anatomy and give exact step-by-step descriptions of these views. MATERIALS AND METHODS: The mitral valvular complex of human cadaveric fresh hearts was investigated from three approaches using 0, 30, and 70 degrees rigid endoscopic optics. In 30 cases after the removal of the hearts, the endoscopes were introduced directly into the aortic root through an aortotomy, left atrium through a standard atriotomy, and apex of the heart through a transmural incision. In 10 cases, the in situ visualization was performed using standard surgical approaches, such as partial upper ministernotomy, right and left minithoracotomy. The investigation was performed first with the mitral valve open, then the left ventricle was filled with saline, and the valve was closed by clamping the aorta. RESULTS: For the visualization of ventricular surfaces of the mitral leaflets and the subvalvular apparatus, the apical approach was most optimal. The aortic approach had limitations at the posterior leaflet. Using the atrial approach, we did not obtain any direct visual information about the subvalvular apparatus with the valve closed. The atrial surfaces of the leaflets were best visible using both the atrial and apical approaches with the mitral valve open. In the case of a closed valve, the apical approach did not allow for an investigation of the atrial surfaces. The aortic approach was useful to visualize the atrial surface of the posterior leaflet with an opened valve. CONCLUSION: In mitral valve repairs through the left atrium, an additional aortic or apical view could be useful to obtain functional information about the subvalvular apparatus by the sealing probe.


Assuntos
Endoscopia , Valva Mitral/anatomia & histologia , Idoso , Idoso de 80 Anos ou mais , Aorta/cirurgia , Feminino , Átrios do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
5.
Gen Physiol Biophys ; 33(2): 177-88, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24177021

RESUMO

Hyperthyroidism elevates cardiovascular mortality by several mechanisms, including increased risk of ischemic heart disease. Therefore, therapeutic strategies, which enhance tolerance of heart to ischemia-reperfusion injury, may be particularly useful for hyperthyroid patients. One promising cardioprotective approach is use of agents that cause (directly or indirectly) A1 adenosine receptor (A1 receptor) activation, since A1 adenosinergic pathways initiate protective mechanisms such as ischemic preconditioning. However, previously we found great A1 receptor reserve for the direct negative inotropic effect of adenosine in isolated guinea pig atria. This phenomenon suggests that weakening of atria is a possible side effect of A1 adenosinergic stimulant agents. Thus, the goal of the present investigation was to explore this receptor reserve in hyperthyroidism. Our recently developed method was used that prevents the rapid intracellular elimination of adenosine, allowing sufficient time for exogenous adenosine administered for the generation of concentration-response curves to exert its effect. Our method also allowed correction for the bias caused by the consequent endogenous adenosine accumulation. Our results demonstrate that thyroxine treatment does not substantially affect the A1 receptor reserve for the direct negative inotropic effect of adenosine. Consequently, if an agent causing A1 receptor activation is administered for any indication, the most probable adverse effect affecting the heart may be a decrease of atrial contractility in both eu- and hyperthyroid conditions.


Assuntos
Adenosina/farmacologia , Átrios do Coração/efeitos dos fármacos , Átrios do Coração/fisiopatologia , Hipertireoidismo/fisiopatologia , Contração Miocárdica/efeitos dos fármacos , Receptor A1 de Adenosina/metabolismo , Adenosina/metabolismo , Animais , Relação Dose-Resposta a Droga , Cobaias , Átrios do Coração/patologia , Hipertireoidismo/metabolismo , Hipertireoidismo/patologia , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Masculino
6.
Arch Pharm Res ; 36(3): 293-305, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23456693

RESUMO

A1 adenosine receptors (A1 receptors) are widely expressed in mammalian tissues; therefore attaining proper tissue selectivity is a cornerstone of drug development. The fact that partial agonists chiefly act on tissues with great receptor reserve can be exploited to achieve an appropriate degree of tissue selectivity. To the best of our knowledge, the A1 receptor reserve has not been yet quantified for the atrial contractility. A1 receptor reserve was determined for the direct negative inotropic effect of three A1 receptor full agonists (NECA, CPA and CHA) in isolated, paced guinea pig left atria, with the use of FSCPX, an irreversible A1 receptor antagonist. FSCPX caused an apparently pure dextral displacement of the concentration-response curves of A1 receptor agonists. Accordingly, the atrial A1 receptor function converging to inotropy showed a considerably great, approximately 80-92 % of receptor reserve for a near maximal (about 91-96 %) effect, which is greater than historical atrial A1 receptor reserve data for any effects other than inotropy. Consequently, the guinea pig atrial contractility is very sensitive to A1 receptor stimulation. Thus, it is worthwhile considering that even partial A1 receptor agonists, given in any indication, might decrease the atrial contractile force, as an undesirable side effect, in humans.


Assuntos
Átrios do Coração/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Agonistas do Receptor Purinérgico P1/farmacologia , Antagonistas de Receptores Purinérgicos P1/farmacologia , Receptor A1 de Adenosina , Xantinas/farmacologia , Animais , Relação Dose-Resposta a Droga , Cobaias , Masculino , Contração Muscular/fisiologia , Técnicas de Cultura de Órgãos , Agonistas do Receptor Purinérgico P1/química , Antagonistas de Receptores Purinérgicos P1/química , Distribuição Aleatória , Receptor A1 de Adenosina/fisiologia , Resultado do Tratamento , Xantinas/química
7.
Gen Physiol Biophys ; 31(4): 389-400, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23255665

RESUMO

The aim of the present study was to investigate whether or not thyroxine (T(4)) treatment affects K(B), the equilibrium dissociation constant of the antagonist-receptor complex, for the interaction between CPX, a selective and competitive orthosteric antagonist, and the guinea pig atrial A1 adenosine receptor A1 receptor). The inotropic response to adenosine, a nonselective adenosine receptor agonist, or CPA, a selective A1 receptor agonist, was investigated in the absence or presence of CPX in paced left atria isolated from 8-day solvent- or T(4)-treated guinea pigs. To obtain K(B) values, adenosine and CPA concentration-response curves were evaluated by Schild analysis. CPA but not adenosine obeyed the requirements of the Schild analysis to provide correct K(B) values for CPX. According to the CPA concentration-response curves, affinity of CPX for the hyperthyroid guinea pig atrial A1 receptor (K(B) = 44.16 nM) was lower than that for the euthyroid one (K(B) = 16.63 nM). Regarding the intense reduction in the negative inotropic effect of adenosine and CPA in hyperthyroid atria, it is reasonable to assume that the moderate decrease in affinity of the guinea pig atrial A1 receptor is only in part responsible for the diminished A1 receptor-mediated effect in hyperthyroidism.


Assuntos
Átrios do Coração/efeitos dos fármacos , Átrios do Coração/metabolismo , Receptor A1 de Adenosina/metabolismo , Tiroxina/farmacologia , Xantinas/farmacologia , Animais , Sinergismo Farmacológico , Cobaias , Masculino , Antagonistas de Receptores Purinérgicos P1 , Resultado do Tratamento
8.
J Cardiothorac Surg ; 7: 12, 2012 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-22289632

RESUMO

BACKGROUND: The left internal mammary artery (LIMA) is the choice for grafting of the left anterior descending coronary artery (LAD). One possible mechanism of the rare graft failure involve the presence of competitive flow. METHOD: 105 patients who had undergone coronary bypass grafting between 1998 and 2000 were included in this observational study. The recatheterizations were performed 28 months after the operations. The rate of patency the LIMA grafts was determined, and the cases with graft failure were analyzed. RESULTS: The LIMA graft was patent in 99 patients (94%). Six patients (6%) exhibited diffuse involution of the graft (string sign). The string sign was always associated with competitive flow as the basis of the LIMA graft involution. In one case quantitative re-evaluation of the preoperative coronary angiography revealed merely less than 50% diameter stenosis on the LAD with a nonligated side-branch of the LIMA. At recatheterization in two patients the pressure wire measurements demonstrated only a non-significant decrease of the fractional flow reserve (0.83 and 0.89), despite the 53% and 57% diameter stenosis in the angiogram. Another patient displayeda significant regression of the LAD lesion between the pre- and postoperative coronary angiography (from 76% to 44%) as the cause of the development of the competitive flow. In one instance, a radial artery graft on the LAD during a redo bypass operation resulted in competitive flow in the radial graft due to the greater diameter than that of the LIMA. In a further patient, competitive flow developed from a short sequential part of the LIMA graft between the nonsignificantly stenosed diagonal branch and the LAD, with involution of the main part of the graft to the diagonal branch. CONCLUSIONS: The most common cause of the development of the string sign of a LIMA graft due to competitive flow is overassessment of the lesion of the LAD. Regression of a previous lesion or some other neighboring graft can also cause the phenomenon.


Assuntos
Arteriopatias Oclusivas/etiologia , Arteriopatias Oclusivas/fisiopatologia , Ponte de Artéria Coronária/efeitos adversos , Artéria Torácica Interna/fisiopatologia , Artéria Torácica Interna/transplante , Fluxo Sanguíneo Regional , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Cardiovasc Ther ; 30(3): 136-44, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21106034

RESUMO

AIMS: The goal of this study was to investigate the importance of the vascular angiotensin convertase enzyme (ACE) in coronary artery bypass graft surgery (CABG) patients. METHODS: Vascular tissue (distal saphenous vein [n= 163] and/or radial artery [n= 120] segments) and blood samples were collected from CABG patients (n= 81). We studied (i) the potency of angiotensin I (AngI) and angiotensin II (AngII) to evoke vascular contractions; (ii) vascular and plasma ACE concentrations; and (iii) ACE genotype of the patients enrolled. RESULTS: The ratio of the potencies (EC(50) ) of AngII and AngI was significantly lower in radial artery compared to the saphenous vein (0.17 ± 0.03 nM and 0.51 ± 0.14 nM, respectively, P= 0.003), suggesting a 3-fold more effective AngI conversion in saphenous vein samples. Angiotensin constrictions were inhibited with telmisartan and captopril in both saphenous veins and radial arteries. Vascular ACE expression was significantly higher in saphenous vein compared to radial artery (9.7 ± 1.0 ng/mg and 5.3 ± 0.7 ng/mg, respectively, P= 0.01). Serum but no tissue ACE concentration was determined by ACE insertion/deletion polymorphism. Accordingly, no relation was found between serum and tissue ACE expression. CONCLUSION: ACE-inhibitor therapy targeting tissue located ACE may be beneficial to patients with saphenous vein grafts after CABG surgery.


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Peptidil Dipeptidase A/metabolismo , Complicações Pós-Operatórias/etiologia , Veia Safena/transplante , Idoso , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Hungria , Masculino , Pessoa de Meia-Idade , Peptidil Dipeptidase A/sangue , Peptidil Dipeptidase A/genética , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/enzimologia , Estudos Prospectivos , Artéria Radial/efeitos dos fármacos , Artéria Radial/enzimologia , Medição de Risco , Fatores de Risco , Veia Safena/efeitos dos fármacos , Veia Safena/enzimologia , Fatores de Tempo , Resultado do Tratamento , Vasoconstritores/farmacologia
11.
J Cell Mol Med ; 15(12): 2614-23, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21199332

RESUMO

The study has analysed the action of histamine in the rabbit venous system and evaluated its potential role in contraction during increased venous pressure. We have found that a great variety exists in histamine sensitivity and H(1) -histamine receptor expression in various types of rabbit veins. Veins of the extremities (saphenous vein, femoral vein, axillary vein) and abdomen (common iliac vein, inferior vena cava) responded to histamine by a prominent, concentration-dependent force generation, whereas great thoracic veins (subclavian vein, superior vena cavas, intrathoracic part of inferior vena cava) and a pelvic vein (external iliac vein) exhibited slight sensitivity to exogenous histamine. The lack of reactivity to histamine was not due to increased activity of nitric oxide synthase (NOS) or heme oxygenase-1. H(1) -histamine receptor expression of veins correlated well with the histamine-induced contractions. Voltage-dependent calcium channels mediated mainly the histamine-induced force generation of saphenous vein, whereas it did not act in the inferior vena cava. In contrast, the receptor-operated channels were not involved in this response in either vein. Tyrosine phosphorylation occurred markedly in response to histamine in the saphenous vein, but not in the inferior vena cava. Histamine induced a prominent ρ kinase activation in both vessels. Protein kinase C and mitogen-activated protein kinase (MAPK) were not implicated in the histamine-induced intracellular calcium sensitization. Importantly, transient clamping of the femoral vein in animals caused a short-term constriction, which was inhibited by H(1) -histamine receptor antagonist in vivo. Furthermore, a significantly greater histamine immunopositivity was detected in veins after stretching compared to the resting state. We conclude that histamine receptor density adapts to the actual requirements of the circulation, and histamine liberated by the venous wall during increased venous pressure contributes to the contraction of vessels, providing a force for the venous return.


Assuntos
Veia Femoral/metabolismo , Histamina/metabolismo , Receptores Histamínicos H1/metabolismo , Veia Safena/metabolismo , Vasoconstrição/fisiologia , Veia Cava Inferior/metabolismo , Animais , Western Blotting , Heme Oxigenase-1/metabolismo , Técnicas Imunoenzimáticas , Masculino , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Coelhos
12.
Arterioscler Thromb Vasc Biol ; 30(7): 1347-53, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20378845

RESUMO

OBJECTIVE: We investigated whether red cell infiltration of atheromatous lesions promotes the later stages of atherosclerosis. METHODS AND RESULTS: We find that oxidation of ferro (FeII) hemoglobin in ruptured advanced lesions occurs generating ferri (FeIII) hemoglobin and via more extensive oxidation ferrylhemoglobin (FeIII/FeIV=O). The protein oxidation marker dityrosine accumulates in complicated lesions, accompanied by the formation of cross-linked hemoglobin, a hallmark of ferrylhemoglobin. Exposure of normal red cells to lipids derived from atheromatous lesions causes hemolysis and oxidation of liberated hemoglobin. In the interactions between hemoglobin and atheroma lipids, hemoglobin and heme promote further lipid oxidation and subsequently endothelial reactions such as upregulation of heme oxygenase-1 and cytotoxicity to endothelium. Oxidative scission of heme leads to release of iron and a feed-forward process of iron-driven plaque lipid oxidation. The inhibition of heme release from globin by haptoglobin and sequestration of heme by hemopexin suppress hemoglobin-mediated oxidation of lipids of atheromatous lesions and attenuate endothelial cytotoxicity. CONCLUSIONS: The interior of advanced atheromatous lesions is a prooxidant environment in which erythrocytes lyse, hemoglobin is oxidized to ferri- and ferrylhemoglobin, and released heme and iron promote further oxidation of lipids. These events amplify the endothelial cell cytotoxicity of plaque components.


Assuntos
Aorta/metabolismo , Aterosclerose/sangue , Eritrócitos/metabolismo , Hematoma/sangue , Heme/metabolismo , Hemoglobinas/metabolismo , Ferro/sangue , Aorta/patologia , Aterosclerose/patologia , Sobrevivência Celular , Células Cultivadas , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Haptoglobinas/metabolismo , Hematoma/patologia , Heme Oxigenase-1/sangue , Hemólise , Hemopexina/metabolismo , Humanos , Peroxidação de Lipídeos , Lipoproteínas LDL/metabolismo , Metemoglobina/metabolismo , Oxirredução , Estresse Oxidativo , Tirosina/análogos & derivados , Tirosina/sangue
13.
J Vasc Surg ; 51(4): 1000-2, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20045621

RESUMO

Intravenous leiomyoma is a benign smooth muscle cell tumor of uterine origin that may grow into the pelvic veins and the inferior vena cava. It usually affects premenopausal women and the majority (90%) are parous. Because cardiac involvement is present in up to 10% of cases, it may be misdiagnosed as a primary cardiac tumor or a venous thrombus-in-transit. We describe a case of intravascular leiomyomatosis with cardiac extension and the morphological particularities of the removed tumor.


Assuntos
Leiomioma/diagnóstico , Neoplasias Uterinas/diagnóstico , Neoplasias Vasculares/diagnóstico , Veia Cava Inferior/patologia , Adulto , Procedimentos Cirúrgicos Cardíacos , Erros de Diagnóstico , Feminino , Átrios do Coração/patologia , Átrios do Coração/cirurgia , Neoplasias Cardíacas/diagnóstico , Ventrículos do Coração/patologia , Humanos , Histerectomia , Leiomioma/patologia , Leiomioma/cirurgia , Mixoma/diagnóstico , Invasividade Neoplásica , Ovariectomia , Resultado do Tratamento , Neoplasias Uterinas/patologia , Neoplasias Uterinas/cirurgia , Neoplasias Vasculares/secundário , Neoplasias Vasculares/cirurgia , Veia Cava Inferior/cirurgia
14.
J Biol Chem ; 284(2): 1031-9, 2009 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-18854307

RESUMO

Prolonged Ca(2+) stimulations often result in a decrease in contractile force of isolated, demembranated human ventricular cardiomyocytes, whereas intact cells are likely to be protected from this deterioration. We hypothesized that cytosolic protein kinase C (PKC) contributes to this protection. Prolonged contracture (10 min) of demembranated human cardiomyocytes at half-maximal Ca(2+) resulted in a 37 +/- 5% reduction of active force (p < 0.01), whereas no decrease (2 +/- 3% increase) was observed in the presence of the cytosol (reconstituted myocytes). The PKC inhibitors GF 109203X and Gö 6976 (10 micromol/liter) partially antagonized the cytosol-mediated protection (15 +/- 5 and 9 +/- 2% decrease in active force, p < 0.05). Quantitation of PKC isoform expression revealed the dominance of the Ca(2+)-dependent PKCalpha over PKCdelta and PKCepsilon (189 +/- 31, 7 +/- 3, and 7 +/- 2 ng/mg protein, respectively). Ca(2+) stimulations of reconstituted human cardiomyocytes resulted in the translocation of endogenous PKCalpha, but not PKCbeta1, delta, and epsilon from the cytosol to the contractile system (PKCalpha association: control, 5 +/- 3 arbitrary units; +Ca(2+), 39 +/- 8 arbitrary units; p < 0.01, EC(50,Ca) = 645 nmol/liter). One of the PKCalpha-binding proteins were identified as the thin filament regulatory protein cardiac troponin I (TnI). Finally, the Ca(2+)-dependent interaction between PKCalpha and TnI was confirmed using purified recombinant proteins (binding without Ca(2+) was only 28 +/- 18% of that with Ca(2+)). Our data suggest that PKCalpha translocates to the contractile system and anchors to TnI in a Ca(2+)-dependent manner in the human heart, contributing to the maintenance of contractile force.


Assuntos
Ventrículos do Coração/enzimologia , Contração Muscular , Miócitos Cardíacos/enzimologia , Proteína Quinase C/metabolismo , Adulto , Cálcio/farmacologia , Citosol/efeitos dos fármacos , Citosol/enzimologia , Ativação Enzimática/efeitos dos fármacos , Feminino , Ventrículos do Coração/efeitos dos fármacos , Humanos , Isoenzimas/metabolismo , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Ligação Proteica , Especificidade por Substrato , Troponina I/metabolismo
15.
J Cell Mol Med ; 13(8B): 2200-2209, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18671759

RESUMO

In this study, we aimed to determine the contribution of peroxynitrite-dependent sulfhydryl group (SH) oxidation to the contractile dysfunction in permeabilized left ventricular human cardiomyocytes using a comparative approach with the SH-oxidant 2,2'-dithiodipyridine (DTDP). Additionally, different antioxidants: dithiothreitol (DTT), reduced glutathione (GSH) or N-acetyl-L-cysteine (NAC) were employed to test reversibility. Maximal isometric active force production (F(o)) and the maximal turnover rate of the cross-bridge cycle (k(tr,max)) illustrated cardiomyocyte mechanics. SH oxidation was monitored by a semi-quantitative Ellman's assay and by SH-specific protein biotinylation. Both peroxynitrite and DTDP diminished F(o) in a concentration-dependent manner (EC(50,peroxynitrite) = 49 microM; EC(50,DTDP) = 2.75 mM). However, k(tr,max) was decreased only by 2.5-mM DTDP, but not by 50 microM peroxynitrite. The diminution of F(o) to zero by DTDP was paralleled by the complete elimination of the free SH groups, while the peroxynitrite-induced maximal reduction in free SH groups was only to 58 +/- 6% of the control (100%). The diminutions in F(o) and free SH groups evoked by 2.5-mM DTDP were completely reverted by DTT. In contrast, DTT induced only a partial restoration in F(o) (DeltaF(o,): approximately 13%; P < 0.05) despite full reversion in protein SH content after 50 microM peroxynitrite. Although, NAC or DTT were equally effective on F(o) after peroxynitrite exposures, NAC or GSH did not restore F(o) or k(tr,max) after DTDP treatments. Our results revealed that the peroxynitrite-evoked cardiomyocyte dysfunction has a small, but significant component resulting from reversible SH oxidation, and thereby illustrated the potential benefit of antioxidants during cardiac pathologies with excess peroxynitrite production.


Assuntos
Antioxidantes/farmacologia , Coração/fisiologia , Contração Miocárdica/efeitos dos fármacos , Miocárdio/metabolismo , Ácido Peroxinitroso/farmacologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Magy Seb ; 61 Suppl: 29-35, 2008.
Artigo em Húngaro | MEDLINE | ID: mdl-18504234

RESUMO

In the last decade a new and more effective method--the vacuum assisted wound closure (VAC)--was introduced for the treatment of the mediastinal wound infections following open heart operations. This technique gained a widespread acceptance in many countries of the world. The Centre of Cardiac Surgery of the University of Debrecen was the first to apply this treatment in Hungary. The authors evaluated the VAC therapy in a retrospective study at their institute. Between September 2002 and December 2005 62 consecutive patients were treated with this method because of wound infection in median sternotomy. Median age of 42 males and 20 females was 63,1 +/- 6,8 years (42-75). All patients had heart surgery (cardio pulmonary bypass) before they developed superficial or deep wound infection in their sternotomy site. Following exploration and radical debridement of the sternotomy wounds, VAC method was used for the treatment of infected wounds until suppuration stopped. When the wound had become macroscopically clear, reconstruction of the sternal defect was performed. This was carried out with well vascularized soft tissue flap(s) (major pectoral muscle and/or omental or pericardial fat pad) in 34 patients, sternal refixation was performed in 13 cases, while 11 patients underwent delayed secondary wound reconstruction with sutures. In one case Ley-prosthesis (sternal stabilisator metal prosthesis) was implanted. Three patients died before the sternal wound reconstruction. As a result of VAC therapy, all infected mediastinal wound cleaned up rapidly and formation of granulation tissue began. The mean period of time from the first sign of the infection to hospital discharge of the patients was 42.2 +/- 18.5 (5-185) days, while the same between sternal reconstruction and discharge was 19.9 +/- 9.6 (1-63) days. The mean duration of VAC therapy was 7.9 +/- 3.4 (1-21) days. The hospital mortality was 11.3% (7/62). Recurrence of the infection occurred in two patients (3.6%). These results suggest that Vacuum-assisted Closure system is an effective and safe method for the treatment of sternotomy wound infections following cardiac surgery. This method facilitates early clean up of infected sternotomy wounds and decreases the recurrence rate significantly.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Procedimentos de Cirurgia Plástica/métodos , Esterno/cirurgia , Retalhos Cirúrgicos , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/terapia , Vácuo , Adulto , Idoso , Feminino , Mortalidade Hospitalar , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Prevenção Secundária , Infecção da Ferida Cirúrgica/microbiologia , Fatores de Tempo
18.
Magy Seb ; 61 Suppl: 41-4, 2008.
Artigo em Húngaro | MEDLINE | ID: mdl-18504236

RESUMO

In this study the authors analyzed the action of Flavon Max product on the cardiovascular system of patients with severe coronary disease. Two randomized, double-blind, placebo controlled trials were carried out using impedance-cardiography, arteriography, vascular Doppler and biochemical laboratory methods. The results demonstrate that Augmentation Index measured with arteriography and C reactive protein (CRP) levels were significantly ameliorated after 2 x 2 months Flavon Max therapy. In conclusion, this product is beneficial as adjuvant in the treatment of atherosclerotic coronary disease.


Assuntos
Fármacos Cardiovasculares/farmacologia , Ponte de Artéria Coronária , Flavonoides/farmacologia , Fenóis/farmacologia , Adulto , Idoso , Angiografia , Proteína C-Reativa/metabolismo , Cardiografia de Impedância , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polifenóis , Fatores de Tempo , Túnica Íntima/patologia , Túnica Média/patologia , Artéria Ulnar/patologia , Ultrassonografia Doppler
19.
Magy Seb ; 61 Suppl: 49-52, 2008.
Artigo em Húngaro | MEDLINE | ID: mdl-18504238

RESUMO

In tricuspid annuloplasty intraoperative "real time" evaluation using transoesophageal echocardiography requires normal flow to get reliable result. It means that the patient has to be already weaned from the cardiopulmonary bypass by the time of evaluation. In the authors' experience a well functioning tricuspid annuloplasty prevents back-flow through the valve. It can be observed on on-pump beating heart. If the tricuspid valve is competent, it is unnecessary to suck the blood flowing back through the coronary sinus while closing the right atrium. This observation seems to correlate well with post cardiopulmonary bypass transoesophageal echocardiography measurements and the control transthoracic echocardiography right before discharging the patients. These statements are based on a group of 72 patients. Sixty-nine patients (95.8%) were discharged (early mortality 4.2%). Only in one case we could observe a discrepancy between the intraoperative surgical observation and the postoperative echocardiographic finding. Development of functional tricuspid regurgitation in left-sided heart disease is a warning sign for myocardial impairment, which is an indication for surgery. Tricuspid annuloplasty can be performed even with moderate to medium grade regurgitation because it improves the early and late outcome. The described method is an adequate method for intraoperative evaluation of the repaired tricuspid valve competency.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Ecocardiografia Transesofagiana , Insuficiência da Valva Tricúspide/fisiopatologia , Insuficiência da Valva Tricúspide/cirurgia , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/fisiopatologia , Adulto , Idoso , Velocidade do Fluxo Sanguíneo , Ecocardiografia , Feminino , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/diagnóstico por imagem
20.
Magy Seb ; 61 Suppl: 53-5, 2008.
Artigo em Húngaro | MEDLINE | ID: mdl-18504239

RESUMO

Mitral valve excision using ultrasound device has not been a routine procedure yet. We used an ultrasonic scalpel for the excision of the calcified mitral valves, which shorten operation time. Further, this technique permits an excision of the valve without applying traction or elevation of the valve from the level of the annulus. This method was first tested on twenty fresh porcine hearts. Subsequently, this technique was carried out with very good results in 15 consecutive patients with calcified or scarred, and distorted mitral valves. Histological samples were taken from the excised human and porcine valves. In porcine histological specimens the destructive effect of the ultrasonic scalpel was measured of an average of 0.7 mm (minimum 0.5 mms, maximum 0.8 mms). However, in the human heart, this effect was an average of 1.1 mms (minimum 0.6 mms, maximum 2.2 mms). There were no early or late complications observed in any case. The authors recommend this technique for excision of calcified mitral valves in cardiac surgery.


Assuntos
Calcinose/cirurgia , Implante de Prótese de Valva Cardíaca/instrumentação , Valva Mitral/patologia , Valva Mitral/cirurgia , Terapia por Ultrassom , Idoso , Animais , Feminino , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Suínos , Resultado do Tratamento
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