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Foram avaliados os efeitos tóxicos do hormônio 17β-estradiol (E2) livre e complexado à β-ciclodextrina (CD) sobre o comportamento e a fisiologia de tilápia (Oreochromis niloticus). Os peixes foram observados por 30 dias, em dois estágios do desenvolvimento (alevino e juvenil), pelo método ad libitum, para a confecção de um etograma. Posteriormente, juvenis foram divididos em três grupos: controle e expostos ao E2 (10ng/L) livre e complexado à β-ciclodextrina (β-CD:E2) por 90 dias. Foram avaliados o comportamento pelo método de varredura instantânea, o consumo de ração, o ganho de peso e a mortalidade em diferentes intervalos. Os alevinos e os juvenis apresentaram frequências de exibição comportamentais diferentes (P<0,05) nos eventos: Afastar (4,7±1,3 e 3,6±0,6%) e Ondulação de repulsão (2,3±0,9 e 1,3±1,0%). Os juvenis expostos ao complexo β-CD:E2 apresentaram aumento (P<0,05) na exibição dos comportamentos agressivos, como Afastar, Ataque caudal, Confronto prolongado, Perseguição, Fuga, e menor mortalidade, quando comparados ao grupo exposto ao E2 livre e controle. Pode-se concluir que a complexação do E2 com a β-CD alterou a toxicidade do E2, pois promoveu um aumento na frequência de exibição dos comportamentos agressivos e interferiu na mortalidade dos animais.(AU)

Toxic effects of free and complexed 17β-estradiol (E2) hormone into β-cyclodextrin (CD) on the behavior and physiology of tilapia (Oreochromis niloticus) were evaluated. The fish were observed for 30 days in two stages of development (fingerling and juvenile) by the ad libitum method to make an ethogram. After this, juveniles were divided into three groups: control and exposed to free E2 (10ng/L) and complexed into β-cyclodextrin (β-CD:E2) for 90 days. The behavior was evaluated through scan sampling method, feed intake, body mass and mortality at different intervals. The fingerlings and juveniles showed behavioral patterns with different display frequencies (P<0.05) for events: Move Away (4.7±1.3 and 3.6±0.6%) and Waving Repulsion (2.3±0.9 and 1.3±1.0%). The juveniles exposed to β-CD:E2 complex showed a significant increase (P<0.05) in the frequency of display of aggressive behaviors as Move Away, Caudal Attack, Clash Extended, Chase, Escape and decrease of mortality when compared to group exposed to free E2 and control. In conclusion, complexation of E2 into β-CD modified E2 toxicity, because it promoted an increase in the frequency of display of aggressive behaviors and it affected the mortality of animals.(AU)

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Foram avaliados os efeitos tóxicos do hormônio 17β-estradiol (E2) livre e complexado à β-ciclodextrina (CD) sobre o comportamento e a fisiologia de tilápia (Oreochromis niloticus). Os peixes foram observados por 30 dias, em dois estágios do desenvolvimento (alevino e juvenil), pelo método ad libitum, para a confecção de um etograma. Posteriormente, juvenis foram divididos em três grupos: controle e expostos ao E2 (10ng/L) livre e complexado à β-ciclodextrina (β-CD:E2) por 90 dias. Foram avaliados o comportamento pelo método de varredura instantânea, o consumo de ração, o ganho de peso e a mortalidade em diferentes intervalos. Os alevinos e os juvenis apresentaram frequências de exibição comportamentais diferentes (P<0,05) nos eventos: Afastar (4,7±1,3 e 3,6±0,6%) e Ondulação de repulsão (2,3±0,9 e 1,3±1,0%). Os juvenis expostos ao complexo β-CD:E2 apresentaram aumento (P<0,05) na exibição dos comportamentos agressivos, como Afastar, Ataque caudal, Confronto prolongado, Perseguição, Fuga, e menor mortalidade, quando comparados ao grupo exposto ao E2 livre e controle. Pode-se concluir que a complexação do E2 com a β-CD alterou a toxicidade do E2, pois promoveu um aumento na frequência de exibição dos comportamentos agressivos e interferiu na mortalidade dos animais.(AU)

Toxic effects of free and complexed 17β-estradiol (E2) hormone into β-cyclodextrin (CD) on the behavior and physiology of tilapia (Oreochromis niloticus) were evaluated. The fish were observed for 30 days in two stages of development (fingerling and juvenile) by the ad libitum method to make an ethogram. After this, juveniles were divided into three groups: control and exposed to free E2 (10ng/L) and complexed into β-cyclodextrin (β-CD:E2) for 90 days. The behavior was evaluated through scan sampling method, feed intake, body mass and mortality at different intervals. The fingerlings and juveniles showed behavioral patterns with different display frequencies (P<0.05) for events: Move Away (4.7±1.3 and 3.6±0.6%) and Waving Repulsion (2.3±0.9 and 1.3±1.0%). The juveniles exposed to β-CD:E2 complex showed a significant increase (P<0.05) in the frequency of display of aggressive behaviors as Move Away, Caudal Attack, Clash Extended, Chase, Escape and decrease of mortality when compared to group exposed to free E2 and control. In conclusion, complexation of E2 into β-CD modified E2 toxicity, because it promoted an increase in the frequency of display of aggressive behaviors and it affected the mortality of animals.(AU)

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INTRODUCTION: In lung transplantation, graft dysfunction is a frequent cause of mortality; the etiopathogenesis is related to ischemia-reperfusion injury. We sought to compare the lung performance of rats after reperfusion after presentation with 3 solutions at 2 ischemia times. METHODS: We randomized 60 male Wistar rats to undergo anterograde perfusion via the pulmonary artery with low-potassium dextran (LPD), histidine-tryptophan ketoglutarate (HTK), or saline. After extraction, the heart-lung blocks were preserved in a solution at hypothermia for 6 or 12 hours before perfusion with homologous blood for 60 minutes using ex vivo system Isolated Perfused Rat or Guinea Pig Lung System (Harvard Apparatus). Respiratory mechanics, pulmonary weight, pulmonary artery pressure (PAP), and relative lung oxygenation capacity (ROC) measurements were obtained every 10 minutes. RESULTS: Comparing tidal volume (TV), compliance, resistance, ROC, PAP, and pulmonary weight the LPD, HTK, and saline group did not differ at 6 and 12 hours. The TV was higher in the lungs with 6-hour ischemia in the LPD, HTK, and saline groups. Compliance was higher in the lungs with 6-hour ischemia in the LPD and saline groups. There were no differences in ROC values comparing lungs with 6- versus 12-hour ischemia in the LPD group. A significant difference was observed between lungs in the HTK and saline groups. Resistance was higher in the lungs with 12-hour ischemia among the LPD, HTK, and saline groups. There was a gradual weight increase in the lungs, particularly those undergoing 12-hour ischemia, despite the absence of a significant difference between groups. CONCLUSION: Rat lungs perfused with LPD and HTK preservation solutions showed similar reperfusion performances in this ex-vivo perfusion model.

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INTRODUCTION: Lung transplantation, a consolidated treatment for end-stage lung disease, utilizes preservation solutions, such as low potassium dextran (LPD), to mitigate ischemia-reperfusion injury. We sought the local development of LPD solutions in an attempt to facilitate access and enhance usage. We also sought to evaluate the effectiveness of a locally manufactured LPD solution in a rat model of ex vivo lung perfusion. METHODS: We randomized the following groups \?\adult of male Wistar rats (n = 25 each): Perfadex (LPD; Vitrolife, Sweden); locally manufactured LPD-glucose (LPDnac) (Farmoterapica, Brazil), and normal saline solution (SAL) with 3 ischemic times (6, 12, and 24 hours). The harvested heart-lung blocks were flushed with solution at 4°C. After storage, the blocks were connected to an IL-2 Isolated Perfused Rat or Guinea Pig Lung System (Harvard Apparatus) and reperfused with homologous blood for 60 minutes. Respiratory mechanics, pulmonary artery pressure, perfusate blood gas analysis, and lung weight were measured at 10-minute intervals. Comparisons between groups and among ischemic times were performed using analysis of variance with a 5% level of significance. RESULTS: Lungs preserved for 24 hours were nonviable and therefore excluded from the analysis. Those preserved for 6 hours showed better ventilatory mechanics when compared with 12 hours. The oxygenation capacity was not different between lungs flushed with LPD or LPDnac, regardless of the ischemic time. SAL lungs showed higher PCO(2) values than the other solutions. Lung weight increased over time during perfusion; however, there were no significant differences among the tested solutions (LPD, P = .23; LPDnac, P = .41; SAL, P = .26). We concluded that the LPDnac solution results in gas exchange were comparable to the original LPD (Perfadex); however ventilatory mechanics and edema formation were better with LPD, particularly among lungs undergoing 6 hours of cold ischemia.

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INTRODUCTION: Lung transplantation has become the mainstay therapy for patients with end-stage lung disease refractory to medical management. However, the number of patients listed for lung transplantation largely exceeds available donors. The study of lung preservation requires accurate, cost-effective small animal models. We have described a model of ex vivo rat lung perfusion using a commercially available system. METHODS: Male Wistar rats weighing 250 g-300 g were anesthetized with intraperitoneal sodium thiopental (50 mg/kg body weight). The surgical technique included heart-lung block extraction, assembly, and preparation for perfusion and data collection. We used an IL-2 Isolated Perfused Rat or Guinea Pig Lung System (Harvard Apparatus, Holliston, Mass, United States; Hugo Sachs Elektronik, Alemanha). RESULTS: Preliminary results included hemodynamic and pulmonary mechanics data gathered in the experiments. CONCLUSION: The isolated rat lung perfusion system is a reliable method to assess lung preservation.

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On a preliminary screening, relevant in vitro antiproliferative activity was observed to the crude ethanolic extract of Pterodon pubescens seed oil against the human melanoma cell line SK MEL 37. The diethyl ether fraction from crude ethanolic extract which exhibited stronger activity was submitted to fractionation by gradient elution with hexane/ethyl acetate. Subfraction A, eluted by hexane/ethyl acetate (80:20), was essentially the most active between all the assayed subfractions with an IC(50) of 37microg/ml calculated by the MTT colorimetric method. At this concentration, subfraction A caused morphological features and internucleosomal DNA fragmentation pattern of apoptosis. Through chromatographic separation, the furane diterpene 1 was isolated from this active subfraction and identified by spectral techniques. Compound 1 showed an IC(50) value of 32microM and fluorescence staining with DAPI revealed some typical nuclear changes which are characteristic of apoptosis. These findings support a role for diterpenoids vouacapan-type skeleton as a model to develop new anticancer agents.

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BACKGROUND: Although coronary angioplasty and myocardial bypass surgery are routinely used, there is no conclusive evidence that these interventional methods offer greater benefit than medical therapy alone. This study is intended to evaluate, in a prospective, randomized, and comparative analysis, the benefit of the 3 current therapeutic strategies for patients with stable angina and single proximal left anterior descending coronary artery stenosis. METHODS AND RESULTS: In a single institution, 214 patients with stable angina, normal ventricular function, and severe proximal stenosis (>80%) on the left anterior descending artery were selected for the study. After random assignment, 70 patients were referred to surgical treatment, 72 to angioplasty, and 72 to medical treatment. The primary end points were the occurrence of acute myocardial infarction or death and presence of refractory angina. After a 5-year follow-up, these combined events were reported in only 6 patients referred to surgery as compared with 29 patients treated with angioplasty and 17 patients who only received medical treatment (P=0.001). However, no differences were noted in relation to the occurrence of cardiac-related death in the 3 treatment groups (P=0. 622). No patient assigned to surgery needed repeat operation, whereas 8 patients assigned to angioplasty and 8 patients assigned to medical treatment required surgical bypass after the initial random assignment. Surgery and angioplasty reduced anginal symptoms and stress-induced ischemia considerably. However, all 3 treatments effectively improved limiting angina. CONCLUSIONS: Bypass surgery for single-vessel coronary artery disease is associated with a lower incidence of medium-term and long-term events as well as fewer anginal symptoms than that found in the patients who underwent angioplasty or medical therapy. In this study, coronary angioplasty was only superior to medical strategies in relation to the anginal status. However, the 3 treatment regimens yielded a similar incidence of acute myocardial infarction and death. Such information should be useful when choosing the best therapeutic option for similar patients.

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OBJETIVO - Avaliar o efeito sublingual do mononitrato-5 de isossobida (MN5IS) e nitroglicerina (NTG) sobre o diâmetro luminal de artérias coronárias epicárdicas, pressão arterial média e efeitos colaterais. MÉTODOS - Cinqüenta pacientes foram submetidos a cateterismo cardíaco e cinecoronariografia, na condição inicial e 5 min após administração sublingual de MN5IS grupo A (GA) ou NTG grupo B (GB). RESULTADOS - O diâmetro coronário de referência aumentou em ambos os grupos, sem significância estatística entre os mesmos. Nos GA e GB foram demosntrados uma diminuição (1,66mmHg) e um aumento (0,79mmHg) na pressão arterial média, respectivamente (p=0,123). Não foram observados efeitos colaterais com o uso destas drogas. CONCLUSÄO - MN5IS sublingual é uma alternativa à administração de NTG durante cinecoronariografia e representa um alternativa terapêutica para o tratamento de doença cardíaca isquêmica.

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We report the use of excimer-laser angioplasty for the treatment of Wiktor and Gianturco-Roubin in-stent restenosis of in two patients. Case 1-a 48-year-old man presented unstable angina five months after Wiktor stent was deployed in right coronary artery. Cardiac catheterization revealed stenosis (95%) within the stent. Case 2-a 65-year-old man presented stable angina four months after Gianturco-Roubin stent was deployed in left anterior descending artery. Cardiac catheterization revealed stenosis (80%) within the stent. Excimer-laser angioplasty within the stent reduced the stenosis to 19% and 30%, respectively. The patients recovered and currently, six months post-procedure, are free of chest pain, and cardiac catheterization revealed stenosis to 30% and 35%, respectively, within the stent. Therefore, the procedure was an effective means of treating restenosis after coronary stent placement, and a prospective comparison of excimer-laser angioplasty and other management alternatives to in-stent restenosis is needed.

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PURPOSE: To evaluate the effect of sublingual isosorbide-5 mononitrate (ISMN) and nitroglycerin (NTG) on luminal diameter of epicardial coronary arteries, mean arterial pressure and deleterious effects. METHODS: Fifty patients were submitted to cardiac catheterization and coronary arteriography, at baseline, and 5 min after sublingual administration of ISMN, group A (GA) or NTG, group B (GB). RESULTS: Reference vessel diameter increased in both groups, without statistical significance. In GA and GB, a decrease (1.66 mmHg) and an increase (0.79 mmHg) in mean arterial pressure, respectively, were demonstrated (p = 0.123). There were no deleterious effects with the use of these drugs. CONCLUSION: Sublingual ISMN is an alternative to administration of NTG during coronary arteriography, and represents a therapeutic alternative to ischemic heart disease treatment.

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PURPOSE: To evaluate the immediate and long term results of percutaneous transluminal coronary balloon angioplasty (PTCA) in patients over 80 years old. METHODS: From 1/1/89 to 6/31/95, 97 patients with 80 years of age or older were submitted to PTCA and were divided into three groups: group A (GrA)-30 patients with stable angina, mean age of 82.5 years, 24 (80%) men; group B(GrB)-40 patients with unstable angina, mean age 81.2 years, 31 (77.5%) men; group C (GrC)-27 patients with myocardial infarction (MI), mean age of 82 years, 16 (59.2%) men. RESULTS: Early outcome-general success rate of 84.5% and mortality rate of 5.1%. The success and mortality rate were in GrA 83.3% and 3.3%, in GrB 85% and 5% and in GrC 85.2% and 7.4%, respectively. Late outcome-the number and percentage of patients with late follow-up and the clinic-angiographic and angiographic restenosis rates were for GrA 19(76%), 52.9%, 75%; GrB 30(88.2%), 30.8%, 61.5% and GrC 12(52.2%), 66.6%, 85.7%, respectively. CONCLUSION: PTCA can be considered an important revascularization alternative in octogenarian patients because of high early success rate, low mortality and acceptable long-term outcome.

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PURPOSE: To determine the patency and incidence rates of left circumflex coronary artery (LCX) as the infarct related artery (IRA) in Q-wave and non-Q wave acute myocardial infarction (AMI). METHODS: Two-hundreds and twenty one patients (172 men) with AMI were stratified in Q and non-Q waves groups. All patients were submitted to cinecoronary angiography 72 hours after the beginning of symptoms and the IRA and its patency were evaluated. RESULTS: In non-Q wave AMI, the LCX was considered to be the IRA in 35% of the patients. In Q wave AMI, this incidence was 8% (p < 0.001). Occlusion of LCX was seen in all non-Q wave AMI patients when it was the IRA. CONCLUSION: The incidence of LCX as IRA was significantly higher in non-Q wave AMI patients. This group did not have the previously expected greater patency rates, what could result in different clinical and evolutive characteristics.

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PURPOSE: To evaluate the importance of the right coronary artery (RCA) patency in patients with right ventricular infarction. METHODS: Fifty-two patients with inferior wall myocardial infarction and right ventricular involvement were studied and divided in two groups: group A (GA) included 35 patients in whom the RCA was patent at coronary angiography, and group B (GB), 17 who had an occluded RCA. They were prospectively evaluated for electrical and hemodynamic complications, as well as in-hospital mortality. RESULTS: The mortality in GA was 11% and 29% in GB, p = 0.13; electrical complications were 11% in GA and 35% in GB, p = 0.06; hemodynamic complications were 8% in GA and 41% in GB, p = 0.009. CONCLUSION: These findings suggest a trend towards reduction in mortality and electrical complications, and significant reduction of hemodynamic complications in patients with inferior wall myocardial infarction with involvement of the right ventricle who have the RCA patent. Thus, RCA patency appears to be important in determining in-hospital outcomes of these patients.

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PURPOSE: To determine the value of magnetic resonance imaging (MRI) in the noninvasive detection of infarct related coronary artery patency after thrombolysis. METHODS: We studied 26 patients with acute myocardial infarction submitted to thrombolysis underwent MRI studies before and after 0.1mmol/kg gadolinium-DTPA injection within the first 48 h of MI. Signal intensity was assessed by circumferential profile analysis techniques. RESULTS: The average ratio of signal intensity of infarcted tissue over normal myocardium (I/N) was significantly higher in patients with patent arteries (1.3 +/- 0.13 vs 1.12 +/- 0.07, p < 0.02). Compared to coronariography MRI, sensitivity of 81% and specificity of 100% for the diagnosis of coronary patency. CONCLUSION: Gadolinium infusion increased infarcted and normal myocardium differentiation. The study of gadolinium kinetics at MRI is a promising technique for noninvasive diagnosis of coronary patency.

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A parada cardiorrespiratória (PCR) é definida como interrupçäo abrupta da ventilaçäo e da perfusäo sistêmica espontânea e efetiva. Há muitos anos se estuda as suas causa e mecanismos, bem como seu manuseio, visando uma ressuscitaçäo com melhores resultados. Na evoluçäo das técnicas de PCR, fatos importantes foram a descriçäo da compressäo torácica externa, fieta em 1960 por Kauwenhoven e Jude, no Johns Honkins Hospital, cujo uso hoje é inquestionável, assim como a cardioversäo elétrica da fibrilaçäo ventricular, com eletrodos aplicados externamente que foi descrita em 1956. Ainda hoje existem pontos que permanecem obscuros e estudos nessa área continuam sendo feitos visando esclarecê-los. Várias conferências foram realizadas, näo apenas para esclarecer alguns pontos, como também para padronizar condutas frente a uma vítima de PCR, para qu se otimize o tratamento, melhorando os índices de sucesso. A conferência da American Heart Association, realizada em 1986, e mais recentemente em 1992, a Conferência nacional de Ressuscitaçäo Cardiopulmonar, representam uma revisäo das recomendaçöes definidas anteriormente. Aqui discutiremos o diagnóstico e o manuseio das vítimas adultas de PCR, procurando dar um enfoque prático e noçòes da fisiopatologia dos eventos relacionados.

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PURPOSE: To evaluate if early interventions which increase flow in the non-infarct related arteries (NRA) could improve long-term ventricular function in the non-infarct (NI) area after an acute myocardial infarction (MI). METHODS: We studied regional wall motion analyzed by the center-line method in two groups of patients with significant stenoses (> or = 70%) in the NRA after successful coronary reperfusion (chemical or mechanical thrombolysis). Group I (GI) consisted of 21 patients that were submitted to early (mean 14 days) complete surgical revascularization of both NRA and infarct related artery (IRA); the 12 group II (GII) patients underwent successful revascularization of the IRA only, with percutaneous transluminal coronary angioplasty (mean 6 days). Paired ventriculograms were obtained within 48 hours of the infarction and a mean of 17 months later. RESULTS: NI area contractility in GI patients improved from -0.35 +/- 2.16 to +0.62 +/- 1.6sd/chord (p < 0.05), whereas in GII decreased from +0.54 +/- 1.78 to -0.66 +/- 1.72 sd/chord (p < 0.05), p < 0.05 between the groups at follow-up. Mean infarct area wall motion did not differ between the two groups: from -3.04 +/- 2.43 to 2.61 +/- 2.49 sd/chord in GI (p = NS), and from -2.68 +/- 2.54 to -2.93 +/- 2.35 sd/chord in GII (p = NS). Mean global left ventricular (LV) ejection fraction did not change in GII patients (0.72 +/- 0.09 and 0.67 +/- 0.12, p = NS), but significantly increased from 0.63 +/- 0.12 to 0.72 +/- 0.11 in GI patients (p < 0.01). CONCLUSION: These data suggest that early revascularization of NRA with significant stenoses can improve not only the NI area regional contractility, but also the global LV function in the long-term follow-up of post MI patients treated with thrombolytic therapy.

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