Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
2.
Eur Heart J Cardiovasc Imaging ; 24(7): 851-862, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-36935401

RESUMO

AIMS: Left ventricular remodelling occurs during the chronic course of aortic regurgitation (AR) and aortic stenosis (AS), leading to myocardial hypertrophy and fibrosis. Several studies have shown that extracellular volume fraction (ECV) and indexed extracellular volume (iECV) are important surrogate markers of diffuse myocardial fibrosis (MF). Postoperative data on these cardiovascular magnetic resonance (CMR) extracellular expansion parameters for either AS or AR are scarce. This study aimed to demonstrate the postoperative changes that occur in diffuse MF, and the influence of preoperative MF on the reversal of LV remodelling, in patients with AR or AS. METHODS AND RESULTS: Patients with severe AR or AS and indications for surgery were prospectively enrolled. Patients underwent pre- and postoperative CMR, and ECV and iECV were quantified. Data from 99 patients were analysed (32 with AR and 67 with AS). After surgery, the left ventricle mass index decreased in both groups (AR: 110 vs. 91 g/m2; AS: 86 vs. 68 g/m2, both P < 0.001). The late gadolinium enhancement fraction (AR: preoperative 1.9% vs. postoperative 1.7%, P = 0.575; AS: preoperative 2.4% vs. postoperative 2.4%, P = 0.615) and late gadolinium enhancement mass (AR: preoperative 3.8 g vs. postoperative 2.5 g, P = 0.635; AS: preoperative 3.4 g vs. postoperative 3.5 g, P = 0.575) remained stable in both groups. Preoperative iECV and ECV were greater in the AR group (iECV: 30 mL/m2 vs. 22 mL/m2, P = 0.001; ECV: 28.4% vs. 27.2%, P = 0.048). Indexed extracellular volume decreased after surgery in both groups (AR: 30-26.5 mL/m2, AS: 22-18.2 mL/m2, both P < 0.001); it was still greater in the AR group (AR: 26.5 mL/m2 vs. AS: 18.2 mL/m2, P < 0.001). Postoperative ECV remained stable in the AR group (preoperative 28.4% vs. postoperative 29.9%; P = 0.617) and increased in the AS group (preoperative 27.2% vs. postoperative 28.6%; P = 0.033). CONCLUSION: Patients with both AR or AS presented reduction in iECV after surgery, unfolding the reversible nature of diffuse MF. In contrast to patients with AS, those with AR developed postoperative iECV regression with stable ECV, suggesting a balanced reduction in both intracellular and extracellular myocardial components.


Assuntos
Insuficiência da Valva Aórtica , Estenose da Valva Aórtica , Cardiomiopatias , Humanos , Meios de Contraste , Gadolínio , Estudos Prospectivos , Miocárdio/patologia , Cardiomiopatias/patologia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/patologia , Fibrose , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/patologia , Espectroscopia de Ressonância Magnética , Imagem Cinética por Ressonância Magnética , Remodelação Ventricular
3.
Am J Physiol Regul Integr Comp Physiol ; 318(3): R529-R544, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31967856

RESUMO

Patients undergoing coronary angiography after myocardial infarction (MI) often develop cardiac and renal dysfunction. We hypothesized that the apolipoprotein A-I mimetic peptide 4F (4F) would prevent those complications. Male Wistar rats were fed a high-cholesterol diet for 8 days. The rats were then anesthetized with isoflurane and randomly divided into five groups: a control group (sham-operated rats), and four groups of rats induced to MI by left coronary artery ligation, the rats in three of those groups being injected 6 h later, with the nonionic contrast agent iopamidol, 4F, and iopamidol plus 4F, respectively. At postprocedure hour 24, we performed the following experiments/tests (n = 8 rats/group): metabolic cage studies; creatinine clearance studies; analysis of creatinine, urea, sodium, potassium, triglycerides, total cholesterol, very low-, low- and high-density lipoproteins (VLDL, LDL, and HDL); immunohistochemistry; histomorphometry; Western blot analysis; and transmission electron microscopy. In another set of experiments (n = 8 rats/group), also performed at postprocedure hour 24, we measured mean arterial pressure, heart rate, heart rate variability, echocardiographic parameters, left ventricular systolic pressure, and left ventricular end-diastolic pressure. 4F protected against MI-induced increases in total cholesterol, triglycerides, and LDL; increased HDL levels; reversed autonomic and cardiac dysfunction; decreased the myocardial ischemic area; minimized renal and cardiac apoptosis; protected mitochondria; and strengthened endothelia possibly by minimizing Toll-like receptor 4 upregulation (thus restoring endothelial nitric oxide synthase protein expression) and by upregulating vascular endothelial growth factor protein expression. 4F-treated animals showed signs of cardiac neovascularization. The nitric oxide-dependent cardioprotection and renoprotection provided by 4F could have implications for post-MI treatment.


Assuntos
Rim/metabolismo , Infarto do Miocárdio/fisiopatologia , Miocárdio/metabolismo , Triglicerídeos/metabolismo , Animais , Vasos Coronários/metabolismo , Coração/fisiopatologia , Masculino , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Ratos , Ratos Wistar , Fator A de Crescimento do Endotélio Vascular/metabolismo
5.
Ann Thorac Surg ; 104(2): 577-583, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28347533

RESUMO

BACKGROUND: Coronary allograft vasculopathy is an inflammatory-proliferative process that compromises the long-term success of heart transplantation and currently has no effective prevention and treatment. Lipid nanoparticles, termed LDE can carry chemotherapeutic agents in the circulation and concentrates them in the heart. METHODS: Twenty-eight rabbits fed a cholesterol-rich diet and submitted to heterotopic heart transplantation were treated with cyclosporine A (10 mg/kg daily) and allocated to four groups of 7 animals treated with intravenous LDE-methotrexate (MTX; 4 mg/kg weekly), with LDE-paclitaxel (PACLI; 4 mg/kg weekly), or with LDE-PACLI (4 mg/kg weekly) and LDE-MTX (4 mg/kg weekly). A control group was treated with only weekly intravenous saline solution. Animals were euthanized 6 weeks later for morphometric, histologic, immunohistochemical, and gene expression analysis of the graft and native hearts. RESULTS: Compared with controls, grafts of rabbits treated with LDE-PACLI showed 50% reduction of coronary stenosis, and in the LDE-MTX and LDE-MTX/PACLI stenosis was approximately 18% less than in control, but this difference was not statistically significant. In the three treatment groups, macrophage infiltration was decreased. In the LDE-MTX group, gene expression of proinflammatory factors tumor necrosis factor-α, monocyte chemoattractant protein 1, interleukin 18, vascular cellular adhesion molecule 1, and matrix metalloproteinase 12 was strongly diminished, whereas expression of antiinflammatory interleukin 10 increased. In the LDE-PACLI and LDE-PACLI/MTX groups, proinflammatory and antiinflammatory gene expressions were not consistently changed by the treatments. CONCLUSIONS: LDE-PACLI promoted strong improvement of cardiac allograft vasculopathy, but the decrease in coronary stenosis by LDE-MTX and LDE-MTX/PACLI was not significant. All three treatments decreased macrophage infiltration in the graft. These results may encourage future clinical trials to test this new therapeutic approach to coronary allograft vasculopathy.


Assuntos
Doença da Artéria Coronariana/tratamento farmacológico , Portadores de Fármacos , Rejeição de Enxerto/prevenção & controle , Transplante de Coração/efeitos adversos , Metotrexato/farmacocinética , Nanopartículas/administração & dosagem , Paclitaxel/farmacocinética , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Doença da Artéria Coronariana/etiologia , Citocinas/biossíntese , Citocinas/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica , Rejeição de Enxerto/genética , Rejeição de Enxerto/metabolismo , Sobrevivência de Enxerto/efeitos dos fármacos , Imuno-Histoquímica , Imunossupressores/administração & dosagem , Imunossupressores/farmacocinética , Injeções Intravenosas , Metotrexato/administração & dosagem , Miocárdio/metabolismo , Paclitaxel/administração & dosagem , RNA/genética , Coelhos , Reação em Cadeia da Polimerase em Tempo Real
6.
Int J Mol Sci ; 17(9)2016 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-27563889

RESUMO

The purpose of our work was to select phages displaying peptides capable of binding to vascular markers present in human atheroma, and validate their capacity to target the vascular markers in vitro and in low-density lipoprotein receptor knockout (LDLr(-/-)) mouse model of atherosclerosis. By peptide fingerprinting on human atherosclerotic tissues, we selected and isolated four different peptides sequences, which bind to atherosclerotic lesions and share significant similarity to known human proteins with prominent roles in atherosclerosis. The CTHRSSVVC-phage peptide displayed the strongest reactivity with human carotid atherosclerotic lesions (p < 0.05), when compared to tissues from normal carotid arteries. This peptide sequence shares similarity to a sequence present in the fifth scavenger receptor cysteine-rich (SRCR) domain of CD163, which appeared to bind to CD163, and subsequently, was internalized by macrophages. Moreover, the CTHRSSVVC-phage targets atherosclerotic lesions of a low-density lipoprotein receptor knockout (LDLr(-/-)) mouse model of atherosclerosis in vivo to High-Fat diet group versus Control group. Tetraazacyclododecane-1,4,7,10-tetraacetic acid-CTHRSSVVC peptide (DOTA-CTHRSSVVC) was synthesized and labeled with (111)InCl3 in >95% yield as determined by high performance liquid chromatography (HPLC), to validate the binding of the peptide in atherosclerotic plaque specimens. The results supported our hypothesis that CTHRSSVVC peptide has a remarkable sequence for the development of theranostics approaches in the treatment of atherosclerosis and other diseases.


Assuntos
Aterosclerose/diagnóstico , Imagem Molecular/métodos , Peptídeos/metabolismo , Animais , Antígenos CD/química , Antígenos de Diferenciação Mielomonocítica/química , Aterosclerose/metabolismo , Modelos Animais de Doenças , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peptídeos/química , Receptores de Superfície Celular/química , Receptores de LDL/deficiência , Receptores de LDL/genética
7.
Cardiovasc Pathol ; 24(5): 290-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26071928

RESUMO

UNLABELLED: There is scanty information concerning multiple aortic aneurysms. Thus, we verified if clinical or pathological characteristics are different in patients with multiple (two or more) aortic aneurysms in comparison with those with only one. MATERIAL AND METHODS: We selected at the necropsy files of the Heart Institute, São Paulo University School of Medicine, the last 100 cases with aortic aneurysms, comparing between the two groups: sex, age, presence of systemic arterial hypertension, diabetes, dyslipedemia, history of smoking habit, cause of the aneurysm, cause of death, and if the diagnosis was reached during life. Age was analysed by Mann-Whitney test, and the other variables by chi-square or Fisher's exact test. RESULTS: Multiple aneurysms corresponded to 14% of cases. The proportion of women among patients with multiple aneurysms was higher than among those with single aneurysm (64.3% versus 20.9%, P<.01), even if only cases with atherosclerosis were taken into consideration (women among multiple-6/10, 60.0%; among single-14/70, 20.0%; P=.01). Smoking was less reported in cases with multiple (4/14, 28.6%) than with single aneurysm (53/86, 61.6%; P=.04); considering cases with atherosclerosis, such difference decreases (40.0% of multiple versus 68.6% of single, P=.09). CONCLUSION: although atherosclerosis is present in most cases of both single and multiple aortic aneurysms, male gender and smoking, considered highly influential in such lesions, are less frequent in patients with multiple than in patients with single aneurysms. Thus mechanisms underlying multiple aortic aneurysms are probably different from those related to single, more common aneurysms.


Assuntos
Aneurisma Aórtico/etiologia , Aneurisma Aórtico/patologia , Fumar/efeitos adversos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
8.
Cardiol Young ; 21(5): 588-90, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21486516

RESUMO

The Shwachman-Diamond syndrome is an autosomal recessive bone marrow failure syndrome with exocrine pancreatic insufficiency. Additional organ systems, such as the liver, heart and bone, may also be affected. We report a patient with a long history of cardiac failure and diagnosis of dilated cardiomyopathy with intermittent neutropenia. Periodic follow-up revealed progressive cardiac failure and pulmonary hypertension. A diagnosis of Shwachman-Diamond syndrome was made at the autopsy.


Assuntos
Doenças da Medula Óssea/complicações , Cardiomiopatia Dilatada/etiologia , Insuficiência Pancreática Exócrina/complicações , Lipomatose/complicações , Adolescente , Evolução Fatal , Feminino , Humanos , Síndrome de Shwachman-Diamond
9.
Histopathology ; 57(6): 917-32, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21166705

RESUMO

AIMS: Thoracic ascending aortic aneurysms (TAA) are characterized by elastic fibre breakdown and cystic medial degeneration within the aortic media, associated with progressive smooth muscle cell (SMC) rarefaction. The transforming growth factor (TGF)-ß/Smad2 signalling pathway is involved in this process. Because the pericellular fibrinolytic system activation is able to degrade adhesive proteins, activate matrix metalloproteinase (MMP), induce SMC disappearance and increase the bioavailability of TGF-ß, the aim was to investigate the plasminergic system in TAA. METHODS AND RESULTS: Ascending aortas [21 controls and 19 TAAs (of three different aetiologies)] were analysed. Immunohistochemistry showed accumulation of t-PA, u-PA and plasmin in TAAs, associated with residual SMCs. Overexpression of t-PA and u-PA was confirmed by reverse transcription-polymerase chain reaction (RT-PCR), immunoblotting and zymography on TAA extracts and culture medium conditioned by TAA. Plasminogen was present on the SMC surface and inside cytoplasmic vesicles, but plasminogen mRNA was undetectable in the TAA medial layer. Plasmin-antiplasmin complexes were detected in TAA-conditioned medium and activation of the fibrinolytic system was associated with increased fibronectin turnover. Fibronectin-related material was detected immunohistochemically in dense clumps around SMCs and colocalized with latent TGF-ß binding protein-1. CONCLUSIONS: The fibrinolytic pathway could play a critical role in TAA progression, via direct or indirect impact on ECM and consecutive modulation of TGF-ß bioavailability.


Assuntos
Aorta/metabolismo , Aneurisma da Aorta Torácica/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Adulto , Idoso , Aneurisma da Aorta Torácica/genética , Western Blotting , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia , Proteína Smad2/genética , Proteína Smad2/metabolismo , Ativador de Plasminogênio Tecidual/genética , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/genética
10.
Ann Thorac Surg ; 90(2): 566-72, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20667351

RESUMO

BACKGROUND: Mesothelial injury is the pivot in the development of adhesions. An increase in the proliferation of mesothelial cells was verified by in vitro studies with the use of keratinocyte growth factor (KGF). This study investigated the influence of KGF associated with thermo-sterilized carboxymethyl chitosan (NOCCts) in the reduction of pericardial adhesions. METHODS: An induction model of pericardial adhesion was carried out in 24 pigs. Animals were randomly allocated to receive topical application of KGF, KGF + NOCCts, NOCCts, or saline (control). At 8 weeks, intrapericardial adhesions were evaluated and a severity score was established. The time spent to dissect the adhesions and the amount of sharp dissection used, were recorded. Histologic sections were stained with sirius red for a morphometric evaluation using a computer-assisted image analysis system. Cytokeratin AE1/AE3 immunostaining were employed to identify mesothelial cells. RESULTS: The severity score expressed in median (minimum to maximum), in relation to the control group (17 [15 to 18]), was lower in the KGF + NOCCts group (7 [6 to 9], p < 0.01) followed by the KGF group (11.5 [9 to 12], 0.01 < p < 0.05) and the NOCCts group (12 [9 to 14], p > 0.05). The dissection time was significantly lower in the KGF + NOCCts group (7.1 + or - 0.6 vs 33.9 + or - 9.2 minutes, p < 0.001). A significantly less sharp dissection was also required in the KGF + NOCCts group. In the adhesion segment, a decreased collagen proportion was found in the KGF + NOCCts group (p < 0.05). Mesothelial cells were present more extensively in groups in which KGF was delivered (p = 0.01). CONCLUSIONS: The use of KGF associated with NOCCts resulted in a synergic action that decreases postoperative pericardial adhesions in a highly significant way.


Assuntos
Quitosana/análogos & derivados , Fator 7 de Crescimento de Fibroblastos/uso terapêutico , Cardiopatias/prevenção & controle , Pericárdio , Animais , Quitosana/uso terapêutico , Sinergismo Farmacológico , Masculino , Suínos , Aderências Teciduais/prevenção & controle
11.
Am J Respir Crit Care Med ; 181(1): 72-9, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19875682

RESUMO

RATIONALE: There are no reports of the systemic human pathology of the novel swine H1N1 influenza (S-OIV) infection. OBJECTIVES: The autopsy findings of 21 Brazilian patients with confirmed S-OIV infection are presented. These patients died in the winter of the southern hemisphere 2009 pandemic, with acute respiratory failure. METHODS: Lung tissue was submitted to virologic and bacteriologic analysis with real-time reverse transcriptase polymerase chain reaction and electron microscopy. Expression of toll-like receptor (TLR)-3, IFN-gamma, tumor necrosis factor-alpha, CD8(+) T cells and granzyme B(+) cells in the lungs was investigated by immunohistochemistry. MEASUREMENTS AND MAIN RESULTS: Patients were aged from 1 to 68 years (72% between 30 and 59 yr) and 12 were male. Sixteen patients had preexisting medical conditions. Diffuse alveolar damage was present in 20 individuals. In six patients, diffuse alveolar damage was associated with necrotizing bronchiolitis and in five with extensive hemorrhage. There was also a cytopathic effect in the bronchial and alveolar epithelial cells, as well as necrosis, epithelial hyperplasia, and squamous metaplasia of the large airways. There was marked expression of TLR-3 and IFN-gamma and a large number of CD8(+) T cells and granzyme B(+) cells within the lung tissue. Changes in other organs were mainly secondary to multiple organ failure. CONCLUSIONS: Autopsies have shown that the main pathological changes associated with S-OIV infection are localized to the lungs, where three distinct histological patterns can be identified. We also show evidence of ongoing pulmonary aberrant immune response. Our results reinforce the usefulness of autopsy in increasing the understanding of the novel human influenza A (H1N1) infection.


Assuntos
Bronquiolite Viral/patologia , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/patologia , Alvéolos Pulmonares/patologia , Adolescente , Idoso , Autopsia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Macrófagos Alveolares/imunologia , Masculino , Pessoa de Meia-Idade , Alvéolos Pulmonares/imunologia , Adulto Jovem
12.
Eur J Cardiothorac Surg ; 35(2): 313-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19008115

RESUMO

BACKGROUND: Several methods have been utilized to prevent pericardial and retrosternal adhesions, but none of them evaluated the mesothelial regenerative hypothesis. There are evidences that the mesothelial trauma reduces pericardial fibrinolytic capability and induces an adhesion process. Keratinocyte growth factor (KGF) has proven to improve mesothelial cells proliferation. This study investigated the influence of keratinocyte growth factor in reducing post-surgical adhesions. METHODS: Twelve pigs were operated and an adhesion protocol was employed. Following a stratified randomization, the animals received a topical application of KGF or saline. At 8 weeks, intrapericardial adhesions were evaluated and a severity score was established. The time spent to dissect the adhesions and the amount of sharp dissection used, were recorded. Histological sections were stained with sirius red and morphometric analyses were assessed with a computer-assisted image analysis system. RESULTS: The severity score was lower in the KGF group than in the control group (11.5 vs 17, p=0.005). The dissection time was lower in the KGF group (9.2+/-1.4 min vs 33.9+/-9.2 min, p=0.004) and presented a significant correlation with the severity score (r=0.83, p=0.001). A significantly less sharp dissection was also required in the KGF group. Also, adhesion area and adhesion collagen were significantly lower in the KGF group than in the control group. CONCLUSION: The stimulation of pericardial cells with KGF reduced the intensity of postoperative adhesions and facilitated the re-operation. This study suggests that the mesothelial regeneration is the new horizon in anti-adhesion therapies.


Assuntos
Fator 7 de Crescimento de Fibroblastos/uso terapêutico , Cardiopatias/prevenção & controle , Pericárdio/cirurgia , Animais , Modelos Animais de Doenças , Dissecação , Avaliação Pré-Clínica de Medicamentos/métodos , Células Epiteliais/efeitos dos fármacos , Cardiopatias/patologia , Cardiopatias/cirurgia , Masculino , Pericárdio/patologia , Proteínas Recombinantes/uso terapêutico , Reoperação , Sus scrofa , Aderências Teciduais/patologia , Aderências Teciduais/prevenção & controle , Aderências Teciduais/cirurgia
13.
Hum Pathol ; 40(3): 306-13, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18973916

RESUMO

Histopathological alterations in human aneurysms and dissections of the thoracic ascending aorta include areas of mucoid degeneration within the medial layer, colocalized with areas of cell disappearance and disruption of extracellular matrix elastic and collagen fibers. We studied the presence of matrix metalloproteinases in relation to their capacity to diffuse through the tissue or to be retained in areas of mucoid degeneration in aneurysms and dissections of the ascending aorta. Ascending aortas from 9 controls, 33 patients with aneurysms, and 14 with acute dissections, all collected at surgery, were analyzed. The morphological aspect was similar whatever the etiology or phenotypic expression of the pathological aortas, involving areas of extracellular matrix breakdown and cell rarefaction associated with mucoid degeneration. Release of proMMP-2, constitutively expressed by smooth muscle cells, was not different between controls and aneurysmal aortas, whereas the aneurysmal aortas released more of the active form. Release of pro and active MMP-9 was also similar between controls and aneurysmal aortas. Immunohistochemical staining of MMP-2 and MMP-9 was weak in both control and pathological aortas. In contrast, released MMP-7 (matrilysin) and MMP-3 (stromelysin-1) could not be detected in conditioned media but were present in tissue extracts with no detectable quantitative difference between controls and pathological aortas. Immunohistochemical staining of MMP-7 and MMP-3 revealed their retention in areas of mucoid degeneration, and semiquantitative evaluation of immunostaining showed more MMP-7 in pathological aortas than in controls. In conclusion, areas of mucoid degeneration, the hallmark of aneurysms, and dissections of thoracic ascending aortas, whatever their etiology, are not inert and can retain specific proteases.


Assuntos
Aorta Torácica/enzimologia , Aneurisma Aórtico/enzimologia , Dissecção Aórtica/enzimologia , Metaloproteases/metabolismo , Dissecção Aórtica/patologia , Aorta Torácica/química , Aorta Torácica/patologia , Aneurisma Aórtico/patologia , Células Cultivadas , Meios de Cultivo Condicionados/química , Técnica Direta de Fluorescência para Anticorpo , Humanos , Técnicas Imunoenzimáticas , Mucinas/metabolismo , Túnica Média/enzimologia , Túnica Média/patologia
14.
Rev. bras. cardiol. invasiva ; 15(4): 378-385, out.-dez. 2007. ilus, tab
Artigo em Português | LILACS | ID: lil-477837

RESUMO

Introdução: Este estudo objetiva avaliar em modelo experimental porcino um novo e pioneiro stent tubular de liga cobalto-cromo e de hastes finas, de concepção brasileira. Objetiva também relatar a experiência inicial de um centro de validação pré-clínica de dispositivos endovasculares instalado no País. Método: No total, 12 porcos domésticos foram submetidos a implante coronário de um novo stent de liga cobalto-cromo não-farmacológico (Scitech Produtos Médicos Ltda.). O stent possuía desenho em anéis corrugados com células curtas (aumento da homogeneidade da cobertura metálica), hastes finas (75μm) e ângulo inter-hastes idealizado para otimizar a força radial. A ligação interanel foi feita por meio de links curtos em formato sinusóide e espessura muito fina (65μm), com espaço circunferencial de 6 mm de diâmetro para acesso a ramo lateral. Dois outros animais receberam stents convencionais de controle para comparação (Driver®, Medtronic Inc., e Matrix®, Sahajanand Medical Technologies). Após um mês, os stents implantados foram retirados para análise microscópica. Resultados: Tanto o stent-teste como os stents comerciais de controle apresentaram hiperplasia neo-intimal discreta a moderada aos 30 dias, com obstrução neo-intimal de 30,0 + 12,2% e 22,4 + 16,5%, respectivamente. Todos os stents, no grupo stentteste e no grupo controle, encontravam-se com alto grau de endotelização, com discreto infiltrado inflamatório e persistência de fibrina discreta ou ausente. Conclusões: Esses achados sugerem que, do ponto de vista da resposta vascular ao implante, o novo stent apresentou desempenho semelhante ao de outros stents não-farmacológicos atualmente em uso comercial.


Background: This study aims to evaluate, in an experimental porcine model, a new and pioneer cobalt-chromium thin-strut coronary stent conceived in Brazil. Also, it aims to report the initial experience of a Brazilian center for pre-clinical validation of endovascular devices. Method: The new bare Cobalt-Chromium stent (Scitech Produtos Médicos Ltda) was implanted in the coronary arteries of twelve domestic pigs. The stent was designed in short rings (for increased homogeneity of vessel scaffolding), thin struts (75 μm) and inter-strut angle engineered to optimize the radial strength. The inter-ring connection was made by a short and very thin link (65 μm) in a curved format, with a circumferential diameter of 6 mm for side branch access. Another two animals received conventional bare metal stents as controls (Driver®, Medtronic Inc., e Matrix®, Sahajanand Medical Technologies). After one month, the implanted stents were excised for microscopic analysis. Results: Both the test-stent and the control commercial stents had mild to moderate neointimal hyperplasia at 30 days, with a neointimal percent obstruction of 30.0 ± 12.2% and 22.4 ± 16.5%, respectively. All stents, in the test-stent and the control groups, had a high degree of endothelialization with a mild inflammatory reaction and absent or mild persistence of fibrin. Conclusions: The present findings suggest that, as regards to the vascular reaction to the implant, the new stent presents a similar performance compared to other bare metal stents currently available for commercial use.


Assuntos
Animais , Próteses e Implantes , Angioplastia Coronária com Balão , Stents , Experimentação Animal , Suínos
15.
Arq. bras. cardiol ; 84(6): 488-491, jun. 2005. ilus
Artigo em Português | LILACS | ID: lil-420012

RESUMO

Descrevemos um caso de pseudoaneurisma de ventrículo esquerdo associado a grave regurgitacão mitral, complicando um infarto ínfero-látero-dorsal. A lesão foi descoberta em ecocardiograma de rotina durante o seguimento ambulatorial. Destacam-se a estratégia cirúrgica bem sucedida, e a boa evolucão clínica da paciente.


Assuntos
Idoso , Humanos , Feminino , Falso Aneurisma/etiologia , Aneurisma Cardíaco/etiologia , Insuficiência da Valva Mitral/etiologia , Infarto do Miocárdio/complicações , Falso Aneurisma/diagnóstico , Falso Aneurisma/cirurgia , Aneurisma Cardíaco/diagnóstico , Aneurisma Cardíaco/cirurgia , Insuficiência da Valva Mitral/diagnóstico , Insuficiência da Valva Mitral/cirurgia , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/cirurgia , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/cirurgia
16.
Mod Pathol ; 16(5): 411-6, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12748246

RESUMO

The development and progression of pulmonary hypertension lesions involve continuous remodeling of the arterial wall, including the extracellular matrix components. The integrity of the internal elastic lamina may represent a barrier to cell migration and formation of intimal proliferative lesions. Some patients with congenital cardiac shunts develop precocious intimal occlusive lesions,whereas others evolve with isolated medial hypertrophy. We studied the 2-D and 3-D morphology of the internal elastic lamina of peripheral pulmonary arteries to search for any difference regarding the type of histological lesion. Fifteen lung biopsies collected for diagnostic purposes from patients with congenital shunts and 6 control lungs (mean ages, 15.8 and 14.7 mo) were studied using the confocal laser scanning microscope, under predetermined conditions of laser intensity, brightness and contrast. We measured the thickness of the internal elastic lamina and determined the number of gaps and projections of elastic tissue towards the medial and intimal layers. The mean internal elastic lamina thickness was significantly higher in arteries from cases with isolated medial hypertrophy when compared with controls and to those with proliferative lesions (P <.05). The number of gaps of the internal elastic lamina was higher in arteries >100 micro m in diameter from the group with intimal lesions when compared to the cases presenting with isolated hypertrophy, but did not differ from the controls. There was a positive linear correlation between the external arterial diameter and the thickness of the internal elastic lamina (r =.74, P <.001) in cases presenting isolated medial hypertrophy. The increased thickness and smaller number of gaps of the internal elastic lamina may act as a barrier that prevents smooth muscle cell migration in patients with pulmonary hypertension without intimal proliferative lesions. On the other hand, a greater number of gaps does not represent, by itself, unrestrained migration, because controls also showed fenestrated laminae.


Assuntos
Tecido Elástico/patologia , Cardiopatias Congênitas/patologia , Hipertensão Pulmonar/patologia , Artéria Pulmonar/patologia , Biópsia , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/complicações , Humanos , Hipertensão Pulmonar/etiologia , Hipertrofia/patologia , Imageamento Tridimensional , Lactente , Masculino , Microscopia Confocal , Túnica Íntima/patologia , Túnica Média/patologia
17.
Cell Transplant ; 11(6): 583-92, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12428748

RESUMO

Vascular smooth muscle cells (VSMC) are ideal for systemic gene therapy because of their proximity to blood vessels and they have demonstrated long-term exogenous gene expression in vivo. However, the procedure generally followed to seed the transduced VSMC onto arteries denuded of endothelial cells usually induces stenosis and thrombosis, with a consequent high risk for use in humans. We demonstrate here that the vascular adventitia is a suitable place to introduce transduced VSMC and to secrete therapeutic proteins into the blood stream by a simple procedure, avoiding postoperative vascular complications. Transduced VSMC, with the retroviral vectors carrying the human growth hormone gene (hGH), were seeded into the adventitia of the rat abdominal aorta by single injection of a cell suspension. Based on the hGH and anti-hGH production in serum and on histological analysis of the removed aortas, we demonstrated hGH production over the 2-month experimental period. None of the animals used in the experiment showed stenosis, thrombosis, or other vascular or visible physiological abnormalities.


Assuntos
Transplante de Células/métodos , Endotélio Vascular/citologia , Expressão Gênica , Músculo Liso Vascular/transplante , Células 3T3 , Animais , Aorta Abdominal , Células Cultivadas , DNA Complementar/genética , Endotélio Vascular/fisiologia , Terapia Genética/métodos , Vetores Genéticos , Hormônio do Crescimento Humano/sangue , Hormônio do Crescimento Humano/genética , Humanos , Cinética , Camundongos , Músculo Liso Vascular/citologia , Regiões Promotoras Genéticas , Ratos , Ratos Wistar , Retroviridae , Sequências Repetidas Terminais , Transfecção/métodos , Zinco/farmacologia
18.
Arq. bras. cardiol ; 79(1): 20-24, July 2002. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-316163

RESUMO

OBJECTIVE: To verify the possible role of adventitial inflammation in atherosclerotic plaque vulnerability and coronary artery remodelling. METHODS: We compared the mean numbers of lymphocytes in the adventitia and in the plaque of ruptured thrombosed and stable equi-stenotic coronary segments of 34 patients who died due to acute myocardial infarction. We also analysed adventitial microvessels, adventitial fibrosis and the external elastic membrane. RESULTS: In the adventitia, the numbers of lymphocytes and microvessels/mm² were 69.5±88.3 and 60.9± 32.1 in culprit lesions and 16.4 ± 21.1 and 44.3±16.1 in stable lesions (p<0.05); within the plaques, the mean number of lymphocytes was 24±40.8 in culprit lesions and 10.9±13.2 in stable ones (p=0.17). The mean percent area of adventitial fibrosis/cross-sectional area of the vessel was significantly lower in unstable plaques (p<0.001). The confocal images showed holes in the external elastic membrane. CONCLUSION: Unstable plaques exhibit chronic pan-arteritis, accompanied by enlargement, medial thinning, and less fibrosis than in stable lesions, which is compatible with vessel aneurysm. Adventitial inflammation may contribute significantly to atheroma instability


Assuntos
Humanos , Doença da Artéria Coronariana , Inflamação , Cadáver , Contagem de Linfócitos , Ruptura
19.
Arq. neuropsiquiatr ; 58(4): 1123-7, Dec. 2000.
Artigo em Inglês | LILACS | ID: lil-273856

RESUMO

We report on a man that had weakness of humeroperoneal distribution associated with limited range of motion of the cervical spine and elbows since he was 5 years old . At age 26 he developed tachycardia episodes. A complex arrhythmia was discovered, and a nodal ablation was done with a cardiac pacemaker implanted. The patient had an arrhythmia and sudden death followed this. Emery-Dreifuss muscular dystrophy is a rare recessive X-linked muscular disorder where mixed patterns in electromyography and muscle histology (neurogenic and/or myopathic) have caused nosological confusion. The autopsy findings are here described and correlated to the clinical features in an attempt to better understand the ambiguous findings concerning the process etiology


Assuntos
Humanos , Masculino , Adulto , Distrofia Muscular de Emery-Dreifuss/patologia , Evolução Fatal
20.
Rev. bras. cir. cardiovasc ; 10(1): 3-17, jan.-mar. 1995. ilus, tab, graf
Artigo em Português | LILACS | ID: lil-164402

RESUMO

A cardiomioplastia tem sido proposta, como uma alternativa ao transplante cardíaco, no tratamento de pacientes com insuficiência miocárdica em fase avançada. O objetivo deste trabalho é estudar a evoluçao clínica e o comportamento da funçao ventricular no pós-operatório tardio desse procedimento em 34 pacientes portadores de cardiomiopatia dilatada, que foram operados no período de maio de 1988 a setembro de 1994. Vinte e sete pacientes estavam em classe funcional III e 7 pacientes em classe IV no pré-operatório, apesar do uso de terapêutica clínica otimizada. A mortalidade hospitalar foi de 2,9 por cento e l paciente que evoluiu em choque cardiogênico foi submetido a transplante cardíaco 42 dias após a cardiomioplastia. O tempo de seguimento pós-operatório variou entre 2 e 73 meses, com média de 27,4 meses. Aos 6 meses de pós-operatório, 12 pacientes estavam em classe funcional I, l5 pacientes em classe II e 3 pacientes em classe III (p=O,OOl) em relaçao ao pré-operatório. Quatorze pacientes faleceram até 5 anos de pós-operatório e os índices de sobrevida foram 84,7 por cento em l ano, 67,7 por cento em 2 anos e 39,6 por cento aos 5 anos de seguimento, sendo que, em 9 pacientes, os óbitos ocorreram por progressao da insuficiência cardíaca, e 5 pacientes faleceram subitamente. A análise de regressao de Cox mostrou que a mortalidade nos pacientes operados em classe funcional IV foi 5,5 vezes maior do que nos pacientes operados em classe III (p=O,OO6), cuja sobrevida foi de 52,7 por cento aos 5 anos de pós-operatório. O estudo sistemático da funçao ventricular através da angiografia com radioisótopos, da ecocardiografia com Doppler e do cateterismo cardíaco direito documentou a melhora da fraçao de ejeçao do ventrículo esquerdo (VE) de 19,8 ñ 3 para 23,9 ñ 7,2 por cento (p

Assuntos
Humanos , Cardiomiopatia Dilatada/cirurgia , Cardiomioplastia , Análise Atuarial , Cardiomiopatia Dilatada/patologia , Hemodinâmica , Período Pós-Operatório , Estudos Prospectivos , Função Ventricular
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA