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1.
Reproduction ; 136(2): 211-24, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18456903

RESUMO

Ovarian antral follicular development is clearly dependent on pituitary gonadotrophins FSH and LH. Although the endocrine mechanism that controls ovarian folliculogenesis leading to ovulation is quite well understood, the detailed mechanisms and molecular determinants in the different follicular compartments remain to be clarified. The aim of this study was to identify the genes differentially expressed in pig granulosa cells along the terminal ovarian follicle growth, to gain a comprehensive view of these molecular mechanisms. First, we developed a specific micro-array using cDNAs from suppression subtractive hybridization libraries (345 contigs) obtained by comparison of three follicle size classes: small, medium and large antral healthy follicles. In a second step, a transcriptomic analysis using cDNA probes from these three follicle classes identified 79 differentially expressed transcripts along the terminal follicular growth and 26 predictive genes of size classes. The differential expression of 18 genes has been controlled using real-time PCR experiments validating the micro-array analysis. Finally, the integration of the data using Ingenuity Pathways Analysis identified five gene networks providing descriptive elements of the terminal follicular development. Specifically, we observed: (1) the down-expression of ribosomal protein genes, (2) the genes involved in lipid metabolism and (3) the down-expression of cell morphology and ion-binding genes. In conclusion, this study gives new insight into the gene expression during pig terminal follicular growth in vivo and suggested, in particular, a morphological change in pig granulosa cells accompanying terminal follicular growth.


Assuntos
Regulação da Expressão Gênica , Células da Granulosa/metabolismo , Folículo Ovariano/fisiologia , Suínos/metabolismo , Animais , Interpretação Estatística de Dados , Feminino , Perfilação da Expressão Gênica/métodos , Glutationa Transferase/genética , Células da Granulosa/citologia , Hibridização In Situ , Metabolismo dos Lipídeos , Lipídeos/genética , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Ribossômicas/genética
2.
J Magn Reson ; 178(1): 96-105, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16239115

RESUMO

Aligned microcontact printing for patterning the sample in areas of homogeneous RF-field on the highly sensitive surface of planar NMR microprobes is presented. We experimentally demonstrate that sample patterning allows drastic improvement of the spin excitation uniformity. The NMR microprobes are designed for cell analysis and characterized using lipid vesicles as cell substitutes. Lipid vesicles are advantageous as composition and concentration of the confined solution are precisely controlled and because of their similarity to living cells. Using aligned microcontact printing, a monolayer of lipid vesicles is immobilized on the surface of the planar NMR microprobe in a patterned way. 1H NMR spectra and CPMG spin echoes of sucrose solution confined within the lipid vesicles are successfully recorded. Nutation curves of the sample structured in different patterns demonstrate the impact of patterning on the spin excitation uniformity. The total detection volumes are between 1 and 2 nL and derived with help of a theoretic model based on 3D finite element simulation. This model predicts the signal-to-noise ratio and the progression of the nutation curves.


Assuntos
Avidina/química , Biotina/química , Lipossomos/química , Espectroscopia de Ressonância Magnética/instrumentação , Desenho de Equipamento , Sensibilidade e Especificidade
3.
J Am Coll Cardiol ; 7(4): 743-51, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3958331

RESUMO

Twenty-six patients presenting with 28 instances of massive acute thrombotic obstruction of a prosthetic valve (16 mitral, 12 aortic) were treated with fibrinolytic agents. In 15 cases the patient presented with acute pulmonary edema and low cardiac output, in 10 with congestive heart failure and embolism and in 3 with peripheral embolism only. The diagnosis of thrombotic obstruction was made by echocardiography or cineradiography, in patients in whom the disc was immobile or barely moving; cineangiography was necessary in only four patients. The fibrinolytic agents administered were streptokinase, 2,000,000 U for 10 hours (14 cases), urokinase, 4,500 U/kg per h for 12 hours (7 cases), or the two agents successively (7 cases). Fibrinolysis was entirely successful in 19 patients: 18 are alive and well without surgical intervention after follow-up of 6 to 64 months and 1 patient had surgical revision after fibrinolysis. In two patients, fibrinolytic treatment was apparently successful but obstruction recurred 4 and 19 months later, respectively, and the patients were again treated by fibrinolysis. In two patients complete failure of fibrinolytic treatment led to emergency surgery, and in three patients improvement was incomplete and death occurred shortly after treatment. No hemorrhagic complications were observed, but there were five cases of embolism during the fibrinolytic treatment. Fibrinolytic treatment would seem to be an attractive, nonsurgical alternative for the thrombosis of a valve prosthesis but, because of the risk of embolism with possible permanent damage, its use should be reserved for critically ill patients who are too sick to undergo immediate surgery.


Assuntos
Próteses Valvulares Cardíacas/efeitos adversos , Estreptoquinase/uso terapêutico , Tromboembolia/tratamento farmacológico , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico , Adolescente , Adulto , Idoso , Valva Aórtica/cirurgia , Aortografia , Cinerradiografia , Ecocardiografia , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/cirurgia , Falha de Prótese , Estreptoquinase/administração & dosagem , Tromboembolia/diagnóstico , Tromboembolia/etiologia , Ativador de Plasminogênio Tipo Uroquinase/administração & dosagem
4.
Cardiovasc Res ; 25(6): 484-90, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1832334

RESUMO

SUBJECT OBJECTIVE: The aim was to determine the effects of nicardipine treatment (10-15 mg.kg-1.d-1 intraperitoneal) on left ventricular hypertrophy, coronary haemodynamics, and mechanical performance in renovascular hypertensive rats. DESIGN: Systemic and coronary haemodynamic variables were evaluated by using microspheres in conscious rats, while mechanical performance and elasticity were measured on isolated papillary muscles from the same animals. EXPERIMENTAL ANIMALS: Male Sprague-Dawley rats, weight 150-180 g, were used. Nine treated rats were compared with control groups, consisting of 9 sham operated, 12 untreated hypertensive, and 9 nephrectomised rats. MEASUREMENTS AND MAIN RESULTS: Eight weeks after clipping, removal of the ischaemic kidney allowed the normalisation of ventricular mass and the reversal of changes induced by hypertrophy except prolongation of timing parameters. Nicardipine administration led to an efficient but incomplete control of blood pressure, which fell from 208(SEM 5) mm Hg in untreated hypertensive rats to 155(4) mm Hg in treated rats, p less than 0.01. After eight weeks of treatment, the reduction in left ventricular mass, from 3.10(0.10) mg.g-1 in untreated rats to 2.72(0.018) mg.g-1 in treated rats was significant (p less than 0.01) but was less than the pressure decrease. In treated hypertensive rats, coronary blood flow was increased and redistributed at rest in favour of the subepicardial layers but was significantly reduced after maximum vasodilatation, to 1.618(0.077) litre.min-1.100 g, in nicardipine treated rats. A reversal of impaired myocardial mechanical indices towards control values was observed except for time to peak force and time to half relaxation. CONCLUSIONS: Nicardipine treatment allowed blood pressure control, reduction of left ventricular mass, and improvement in mechanical performance, but was unable to restore minimal coronary vascular resistance. The results suggest that, although blood pressure decrease is obviously important, it may not be the sole factor in the reversal of cardiac hypertrophy.


Assuntos
Cardiomegalia/tratamento farmacológico , Hemodinâmica/efeitos dos fármacos , Hipertensão Renovascular/fisiopatologia , Nicardipino/uso terapêutico , Animais , Cardiomegalia/etiologia , Hipertensão Renovascular/complicações , Hipertensão Renovascular/tratamento farmacológico , Masculino , Contração Miocárdica/efeitos dos fármacos , Nefrectomia , Ratos , Ratos Endogâmicos
5.
Hypertension ; 11(6 Pt 1): 495-501, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2968307

RESUMO

The effects of diltiazem treatment (40-50 mg/kg/day orally for 8 weeks) of left ventricular hypertrophy on systemic and coronary hemodynamics and mechanical cardiac performance were investigated in renovascular hypertensive rats (Goldblatt, two-kidney, one clip). Systemic and coronary hemodynamics were determined by using radioactive microspheres in conscious, unrestrained rats. Mechanical performance was measured on isolated papillary muscle from the same animal. Nine treated hypertensive rats were compared with control groups: 12 untreated hypertensive and nine sham-operated rats. Diltiazem treatment led to an effective but incomplete control of blood pressure (from 208 +/- 5 mm Hg in the untreated hypertensive group to 155 +/- 3 mm Hg in the treated hypertensive group; p less than 0.01) associated with a significant but incomplete decrease of the left ventricular mass (from 3.10 +/- 0.19 mg/g in untreated hypertensive rats to 2.35 +/- 0.04 mg/g in treated hypertensive rats; p less than 0.01). A close correlation was found between left ventricular mass and systolic blood pressure in untreated, treated, and pooled groups (r = 0.84, p less than 0.001, n = 30). The left ventricular weight to systolic blood pressure ratio was equivalent in all three groups, so that the reduction of left ventricular mass in diltiazem-treated rats was commensurate with the reduction of blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Cardiomegalia/tratamento farmacológico , Diltiazem/farmacologia , Hipertensão Renovascular/tratamento farmacológico , Administração Oral , Animais , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Circulação Coronária/efeitos dos fármacos , Diltiazem/administração & dosagem , Esquema de Medicação , Avaliação Pré-Clínica de Medicamentos , Contração Isométrica , Masculino , Microesferas , Contração Miocárdica/efeitos dos fármacos , Ratos , Ratos Endogâmicos SHR , Fatores de Tempo , Resistência Vascular/efeitos dos fármacos
6.
J Nucl Med ; 25(11): 1167-74, 1984 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6333492

RESUMO

We describe a quantitative method that measures segmental motion of the left ventricle, using tomographic slices obtained by gated single photon emission tomography (GSPECT). These slices contain the major axis of the left ventricle and are presumed to show wall motion directed towards a center of contraction. Values of parameters describing segmental wall motion in GSPECT were obtained from 61 patients, who received a left cardiac catheterization 1 hr later. These values were compared with results of similar calculations applied to data from contrast ventriculography. We conclude that GSPECT allows a detailed and quantitative, noninvasive study of wall motion of all left ventricular segments, with high inter- and intraobserver reproducibility.


Assuntos
Coração/diagnóstico por imagem , Tomografia Computadorizada de Emissão , Angiocardiografia , Humanos , Contração Miocárdica , Volume Sistólico
7.
Thromb Haemost ; 76(6): 1020-9, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8972027

RESUMO

In idiopathic thrombocytopenic purpura (ITP), autoantibodies reacting with antigens on the platelet membrane bring about accelerated platelet destruction. We now report PAICA ("Platelet-Associated IgG Characterization Assay"), a method for detecting autoantibodies bound to specific membrane glycoproteins in total platelet lysates. This monoclonal antibody (MAb) capture assay takes into account the fact that antibodies on circulating platelets may be translocated to internal pools as well as being on the surface. A total of twenty ITP patients were examined by PAICA, and the results compared with those obtained by measuring (i) serum antibodies bound to paraformaldehyde-fixed control platelets by ELISA, (ii) IgG bound to the surface of the patient's own platelets by flow cytometry (PSIgG), (iii) total platelet-associated IgG (PAIgG) by ELISA and (iv) serum antibodies reacting with control platelets by MAIPA ("Monoclonal Antibody-specific Immobilization of Platelet Antigens"). Of twelve patients with elevated PAIgG, nine had increased PSIgG yet eleven reacted positively in PAICA. Of these, eight possessed antibodies directed against GP IIb-IIIa, two against GP Ib-IX and one patient possessed antibodies directed against GP IIb-IIIa and GP Ia-IIa respectively. Only seven of the patients possessed serum antibodies detectable by MAIPA. PAICA was also able to detect platelet-associated c7E3 (the chimeric form of Fab fragments of the MAb 7E3) following its infusion during antithrombotic therapy, when it proved more sensitive over a seven-day period than a MAIPA assay adapted for assessing surface-bound antibody. We propose that PAICA provides added sensitivity to the detection of platelet-associated antibodies in immune thrombocytopenias or following therapy with humanized MAbs.


Assuntos
Antígenos de Plaquetas Humanas/imunologia , Autoanticorpos/análise , Imunoensaio/métodos , Imunoglobulina G/análise , Púrpura Trombocitopênica Idiopática/imunologia , Adulto , Idoso , Autoanticorpos/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/análise , Inibidores da Agregação Plaquetária/imunologia , Sensibilidade e Especificidade
8.
Am J Cardiol ; 79(5): 545-52, 1997 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-9068506

RESUMO

To assess the effect of optimal directional coronary atherectomy (DCA) on restenosis and left ventricular (LV) function, 95 patients who underwent DCA and adjunctive balloon angioplasty for de novo lesions were prospectively followed for 6 months. Absolute and relative coronary lumen measurements were analyzed with online quantitative coronary angiography. LV volumes, ejection fraction, and segmental wall motion were measured off-line according to the radial method for LV cineangiograms acquired in a right anterior oblique projection. Target vessels were the left anterior descending artery in 63 patients and right coronary artery in 32. Mean (+/- SD) reference diameter was 3.58 +/- 0.65 mm. Mean lumen diameter improved significantly after DCA from 1.19 +/- 0.44 to 3.03 +/- 0.45 mm, yielding a 14 +/- 10% residual stenosis. Overall angiographic restenosis rate (> 50% stenosis in diameter) at control was 23%. In patients without restenosis, there were no significant changes in LV volumes or in LV pressures. In this subgroup, ejection fraction improved significantly in the left anterior descending group (mean difference 3 +/- 10%, p < 0.04). Moreover, there was an increase in fractional shortening of all anterior segments (mean difference 11 +/- 16%, p < 0.005). Improvement in fractional shortening was less marked in the right coronary artery group even without restenosis. We conclude that: (1) optimal DCA can achieve a low restenosis rate in selected large vessels, (2) long-term beneficial effects on regional LV function are possible, particularly in patients with left anterior descending disease and in the absence of coronary restenosis.


Assuntos
Aterectomia Coronária , Doença da Artéria Coronariana/cirurgia , Doença das Coronárias/cirurgia , Função Ventricular Esquerda , Angioplastia Coronária com Balão , Volume Cardíaco , Cinerradiografia , Constrição Patológica/fisiopatologia , Constrição Patológica/cirurgia , Constrição Patológica/terapia , Angiografia Coronária , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/terapia , Doença das Coronárias/fisiopatologia , Doença das Coronárias/terapia , Vasos Coronários/patologia , Vasos Coronários/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Estudos Prospectivos , Recidiva , Volume Sistólico , Pressão Ventricular
9.
Br J Pharmacol ; 117(7): 1593-9, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8730759

RESUMO

1. In order to develop a predictive model for the preclinical evaluation of anthracycline cardiotoxicity and the means of preventing it, we have studied the functional parameters of perfused hearts isolated from rats receiving repeated doses of several anthracyclines. 2. The anthracyclines studied were doxorubicin, epirubicin, pirarubicin and daunorubicin, and we also studied a liposomal formulation of daunorubicin (DaunoXome) and the co-administration of dexrazoxane (ICRF-187) and doxorubicin. 3. Anthracyclines were administered i.p. at equimolar doses corresponding to 3 mg kg-1 per injection of doxorubicin, every other day for a total of six doses. Dexrazoxane was used at the dose of 30 mg kg-1 per injection and was administered either 30 min before or 30 min after doxorubicin. We evaluated any general toxicity towards the animals as well as alterations of left ventricular contractility and relaxation ex vivo. 4. Epirubicin and daunorubicin were significantly less cardiotoxic than doxorubicin, and neither pirarubicin nor DaunoXome caused significant alterations in cardiac function. There was a direct relationship between the decrease in cardiac contractility or relaxation and anthracycline accumulation in the heart, evaluated after the same treatment schedule. 5. Dexrazoxane induced a significant protection against doxorubicin-induced cardiac toxicity when administered 30 min before doxorubicin, whereas this protection was ineffective when administered 30 min after doxorubicin. Direct perfusion of DaunoXome in isolated hearts of untreated animals resulted in a 12-fold reduction of the accumulation of daunorubicin in heart tissue as compared to the perfusion of free daunorubicin, and did not cause alterations in cardiac function at a dosage for which free daunorubicin induced major alterations. 6. The isolated perfused rat heart appears to be a valuable model for screening of new anthracyclines and of strategies for circumventing anthracycline cardiotoxicity.


Assuntos
Antraciclinas/toxicidade , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Avaliação Pré-Clínica de Medicamentos/métodos , Coração/efeitos dos fármacos , Animais , Antraciclinas/administração & dosagem , Quimioterapia do Câncer por Perfusão Regional , Daunorrubicina/toxicidade , Coração/fisiologia , Cardiopatias/induzido quimicamente , Cardiopatias/prevenção & controle , Técnicas In Vitro , Lipossomos , Masculino , Miocárdio/metabolismo , Ratos , Ratos Sprague-Dawley , Razoxano/administração & dosagem , Razoxano/farmacologia , Função Ventricular Esquerda/efeitos dos fármacos , Pressão Ventricular/efeitos dos fármacos
10.
Am J Hypertens ; 4(3 Pt 2): 235S-239S, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1828352

RESUMO

We studied the effects of perindopril on left ventricular hypertrophy, systemic and coronary hemodynamics, and mechanical cardiac performance in renovascular hypertensive rats (Goldblatt, two-kidneys, one-clip). Systemic and coronary hemodynamics, before and after carbochrome infusion, were assessed by radioactive microspheres injection via an atrial catheter in conscious rats. Mechanical performance was measured on isolated papillary muscle from the same animal. Twelve treated hypertensive rats were compared with 10 nontreated hypertensive rats and nine sham-operated normotensive rats of the same age. Perindopril treatment induced a complete control of blood pressure (mean blood pressure from 156 +/- 22 mm Hg in the untreated group to 100 +/- 24 mm Hg in the treated group (P less than .01), compared to 106 +/- 18 mm Hg in the sham group). This was associated with a nearly complete regression of left ventricular hypertrophy (left ventricular mass/body weight 2.26 +/- 0.38 mg/g in the treated group v 3.1 +/- 0.6 in the untreated group [P less than .01], compared to 2 +/- 0.25 mg/g in the sham group [p = NS]). Minimal left ventricular coronary resistances after carbochrome were slightly higher in the hypertensive group compared both to sham and treated group. A reversal of impaired myocardial mechanical parameters towards control values was observed, except for some parameters of relaxation. We conclude that perindopril allows in this model a complete control of blood pressure, and a regression of left ventricular hypertrophy with normalization of coronary hemodynamics and contractile function.


Assuntos
Hipertensão Renovascular/tratamento farmacológico , Indóis/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Fenômenos Biomecânicos , Pressão Sanguínea/efeitos dos fármacos , Cardiomegalia/tratamento farmacológico , Cardiomegalia/etiologia , Circulação Coronária/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Hipertensão Renovascular/complicações , Hipertensão Renovascular/fisiopatologia , Masculino , Contração Miocárdica/efeitos dos fármacos , Perindopril , Ratos , Ratos Endogâmicos
11.
Cancer Chemother Pharmacol ; 35(3): 257-61, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7805186

RESUMO

We have compared the cardiotoxicity of 3 anthracyclines in a model of isolated perfused rat heart using the Langendorff technique. The contractile state and ventricular compliance were studied. Doxorubicin, epirubicin and pirarubicin were perfused at concentrations of 10(-6) and 10(-5) M during 70 min. The cardiac accumulation of the drugs was studied by HPLC. No significant alteration of cardiac functional parameters was observed at 10(-6) M. At 10(-5) M, epirubicin produced a significantly greater alteration of cardiac contractility than doxorubicin, whereas pirarubicin exerted first an inotropic effect followed by a recovery to initial values at the 60th min. Anthracycline accumulation in the heart was dose-dependent; epirubicin accumulated to a 30% greater extent than doxorubicin and pirarubicin heart concentrations were 4-5 times higher than those of doxorubicin at the end of the perfusion. These results suggest that doxorubicin and epirubicin have the same intrinsic cardiac toxicity, and that their distinct clinical cardiotoxicity must be explained by pharmacokinetic differences, whereas pirarubicin is much less cardiotoxic than the other anthracyclines because of different pharmacodynamic properties.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Doxorrubicina/análogos & derivados , Doxorrubicina/toxicidade , Epirubicina/toxicidade , Coração/efeitos dos fármacos , Animais , Antibióticos Antineoplásicos/metabolismo , Relação Dose-Resposta a Droga , Doxorrubicina/metabolismo , Epirubicina/metabolismo , Masculino , Modelos Biológicos , Contração Miocárdica/efeitos dos fármacos , Miocárdio/metabolismo , Técnicas de Cultura de Órgãos , Perfusão , Ratos , Ratos Sprague-Dawley , Função Ventricular Esquerda/efeitos dos fármacos
12.
Leuk Lymphoma ; 31(3-4): 423-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9869208

RESUMO

We report a fatal primary cardiac non-Hodgkin's lymphoma in a 62 years old immunocompetent woman presenting with tamponade and complete atrioventricular block. CT-scan, echocardiography and autopsy examination showed a tumor largely infiltrating the heart without extracardiac involvement. A surgical biopsy revealed high grade B-cell non-Hodgkin's lymphoma with a misleading myelomonocytic CD68 (KPI) expression. Polymerase Chain Reaction analysis revealed a clonal rearrangement of the immunoglobulin heavy chain gene and confirmed the B-cell origin of the lymphoma. Our report also emphasizes the role of immunohistochemical and molecular techniques in the diagnosis.


Assuntos
Neoplasias Cardíacas/patologia , Neoplasias Cardíacas/fisiopatologia , Linfoma de Células B/patologia , Linfoma de Células B/fisiopatologia , Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Feminino , Bloqueio Cardíaco/etiologia , Bloqueio Cardíaco/patologia , Bloqueio Cardíaco/fisiopatologia , Neoplasias Cardíacas/complicações , Humanos , Linfoma de Células B/complicações , Pessoa de Meia-Idade
13.
J Magn Reson ; 164(2): 242-55, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14511593

RESUMO

Microfabricated small-volume NMR probes consisting of electroplated planar microcoils integrated on a glass substrate with etched microfluidic channels are fabricated and tested. 1H NMR spectra are acquired at 300 MHz with three different probes having observed sample volumes of respectively 30, 120, and 470 nL. The achieved sensitivity enables acquisition of an 1H spectrum of 160 microg sucrose in D2O, corresponding to a proof-of-concept for on-chip NMR spectroscopy. Increase of mass-sensitivity with coil diameter reduction is demonstrated experimentally for planar microcoils. Models that enable quantitative prediction of the signal-to-noise ratio and of the influence of microfluidic channel geometry on spectral resolution are presented and successfully compared to the experimental data. The main factor presently limiting sensitivity for high-resolution applications is identified as being probe-induced static magnetic field distortions. Finally, based on the presented model and measured data, future performance of planar microcoil-based microfluidic NMR probes is extrapolated and discussed.


Assuntos
Espectroscopia de Ressonância Magnética/instrumentação , Microquímica/instrumentação , Microfluídica/instrumentação , Sacarose/química , Transdutores , Eletrônica , Desenho de Equipamento , Análise de Falha de Equipamento , Espectroscopia de Ressonância Magnética/métodos , Microquímica/métodos , Microfluídica/métodos , Miniaturização , Sensibilidade e Especificidade
14.
Thromb Res ; 55(1): 5-11, 1989 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-2506661

RESUMO

Patients with symptoms of deep vein thrombosis for less than 10 days were treated with a standard dose of heparin. In the open label phase of the trial, 11 patients received 100 mg rt-PA on the first day and 50 mg on the subsequent day in an 8 hour infusion. In the double-blind phase, 8 patients were randomized to the same rt-PA regimen, 6 patients to an infusion of 50 mg rt-PA over 8 hours on days 1 and 2, and 7 patients to placebo infusions. The mean change in venographic score in all patients treated with rt-PA plus heparin is -3.8 units compared to -0.6 units in patients treated with heparin alone (p = 0.06). Bleeding complications classified as major were noted in 8/25 patients receiving the combined treatment.


Assuntos
Tromboflebite/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Adolescente , Adulto , Idoso , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Heparina/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Pelve , Projetos Piloto , Distribuição Aleatória , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Ativador de Plasminogênio Tecidual/efeitos adversos
15.
Blood Coagul Fibrinolysis ; 6(5): 395-410, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8589205

RESUMO

We report the detection of activated GP IIb-IIIa complexes on platelets of patients undergoing thrombolytic therapy after acute myocardial infarction. Protocols were established for the monoclonal antibodies (mAbs): VH10, anti-P-selectin, a marker of platelet secretion; 9F9 and F26, two anti-RIBS (receptor-induced binding sites) mAbs specific for fibrinogen (Fg) bound to the GP IIb-IIIa receptor. Of ten patients studied: two were treated with streptokinase, four with APSAC (anisoylated plasminogen-streptokinase activator complex), and three with rt-PA. Platelets were tested on at least five occasions in the week following therapy. The percentage of platelets positive with 9F9 was often high, and reached a maximum within three days. By this time, plasma Fg levels, which fell during fibrinolysis, had begun to return to normal. Levels of activated platelets had fallen to baseline after 7 days. PAC-1, a mAb which binds directly to the activated GP IIb-IIIa complex, confirmed the results with 9F9, but F26 was a less sensitive probe. Binding of the anti-P-selectin mAb (VH10) was low, showing that little secretion had occurred. A concentration-dependent inhibition of 9F9 binding by RGDW peptide, a competitive inhibitor for Fg on GP IIb-IIIa, confirmed that Fg (or epitope-containing degradation products) were being located by the antibody. The activation of GP IIb-IIIa occurred despite the patients receiving aspirin and heparin. Thus platelets of some fibrinolytic patients have an increased tendency for surface activation within the first 72 h after treatment, a finding which would be compatible with an increased thrombotic tendency.


Assuntos
Plaquetas/metabolismo , Citometria de Fluxo , Infarto do Miocárdio/sangue , Infarto do Miocárdio/tratamento farmacológico , Glicoproteínas da Membrana de Plaquetas/metabolismo , Terapia Trombolítica , Adulto , Idoso , Sequência de Aminoácidos , Anistreplase/uso terapêutico , Anticorpos Monoclonais , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Ativação Plaquetária , Contagem de Plaquetas , Proteínas Recombinantes/uso terapêutico , Estreptoquinase/uso terapêutico , Ativador de Plasminogênio Tecidual/uso terapêutico
16.
Eur J Cardiothorac Surg ; 5(4): 167-74; discussion 175, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2059449

RESUMO

From December 1971 to December 1989, 62 patients (pts) 42 males, 20 females, mean age 66 years (yr) 6 months (mth) (range 52-80) were operated upon for post-infarction ventricular septal defect (VSD), (anterior 34, inferior 28). Eight pts (13%), group (G) 1 presented with cardiogenic shock, 19 pts (30.5%), G2 with severe congestive heart failure (CHF); 31 pts (50%), G3 were stable with mild CHF and 4 pts (6.5%), G4 without CHF. Preoperative intra-aortic balloon pumping (IABP) was used in 49 pts (79%). One transplanted pt was excluded from this study. The VSD was closed from 1 day (d) to 5 mth (mean 13 d) after its occurrence. Hospital death (HD) occurred in 23 pts (37.7% +/- 6%). Of 44 incremental risk factors (RF) for HD studied, the preoperative status (PS) was the most significant (P less than 0.01). G1: 87% +/- 12%, G2: 42% +/- 12%, G3: 25.8% +/- 8%, G4: 0%. [table: see text] Non-survivors had a shorter mean delay between VSD occurrence and surgery than survivors: 5.6 +/- 3.7 d vs 18.2 +/- 30 d (P less than 0.05), but this delay was correlated to PS. The follow-up of the 38 early survivors ranges from 2 mth to 14 yr (mean 3 yr, 11 mth); 11 pts died between 45 d and 14 yr. No RF was identified for premature late death. HD included, the actuarial survival rate at 1, 5, 10 yr is: 57% (+/- 7%), 44% (+/- 8%), 30% (+/- 10%), respectively.


Assuntos
Ruptura Cardíaca Pós-Infarto/cirurgia , Comunicação Interventricular/cirurgia , Complicações Pós-Operatórias/mortalidade , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Ponte de Artéria Coronária , Feminino , Seguimentos , Ruptura Cardíaca Pós-Infarto/mortalidade , Comunicação Interventricular/mortalidade , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Taxa de Sobrevida
17.
Ultrasound Med Biol ; Suppl 2: 325-30, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6545740

RESUMO

UNLABELLED: Recent improvements in surgical technics have dramatically changed the outcome of patients with aortic dissection (AD). The aim of this work is to evaluate the reliability of two dimensional echocardiography (2DE) in the diagnosis of AD. The 2DE was recorded in all patients with a systematic approach in order to visualize the entire aorta (Ao). 58 cases were studied in a three years period. At the beginning of this study we validate 2DE by comparison with angiography (angio) in 14 of our first patients: the 2 angio criteria (dilatation, abnormal intraluminal image) have been found on 2DE in 12 pts (92%), with intraluminal image) have been found on 2DE in 12 pts (92%), with no significant difference between internal diameter of Ao on angio and 2DE. In our experience with 58 pts a positive diagnosis was possible in 90% of AD type I and only 18% of AD type III. IN CONCLUSION: 2DE is a practical and valuable method for the assessment of type I and II AD. Two 2DE criteria must be present at the same anatomical level (dilatation, abnormal intraluminal echo). In these conditions we have been able to avoid aortography in 26 of our last patients with type I and II.


Assuntos
Aneurisma Aórtico/diagnóstico , Dissecção Aórtica/diagnóstico , Ecocardiografia/métodos , Adulto , Idoso , Dissecção Aórtica/diagnóstico por imagem , Angiografia , Aneurisma Aórtico/diagnóstico por imagem , Erros de Diagnóstico , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Eur J Radiol ; 1(3): 241-4, 1981 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7341262

RESUMO

This paper reviews 25 intracardiac tumours (12 myxomas and 13 thrombi) studied by T.M. echography, bidimensional (2-D) echography and cineangiography during a two year period. In addition, five cardiac tumours (two myxomas, three thrombi) were studied by echography alone, and correctly diagnosed. T.M. echography gives false negative results, whereas both 2-D echo and cineangiography give reliable diagnosis. However, 2-D echo should be the procedure of choice as it is non-invasive, and may be used on patients with equivocal symptoms. Since bidimensional echography has become available during the past two years, 12 myxomas have been correctly diagnosed, compared to 14 found during the previous 13 years.


Assuntos
Ecocardiografia , Neoplasias Cardíacas/diagnóstico , Mixoma/diagnóstico , Cineangiografia , Cardiopatias/diagnóstico , Humanos , Trombose/diagnóstico
19.
Clin Cardiol ; 12(4): 215-20, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2565776

RESUMO

AR-C 239 is a new specific alpha 1 antagonist drug with an action similar to that of prazosin. In dogs it appears to be specific for the alpha 1 adrenoreceptor. AR-C 239 was tested in 11 patients (49 +/- 11 years old) with left heart failure, who had not received any previous treatment. The drug was infused intravenously with a stepwise increase in dose, producing three stable plasma concentration plateaus: 10 +/- 2, 51 +/- 3, and 138 +/- 55 ng/ml. Hemodynamic data were collected at time T0 before drug infusion, and half-way through each infusion. Blood pressures and cardiac output were recorded using a Millar microtip manometer (left ventricle), a Swan-Ganz catheter (pulmonary artery), and a femoral catheter, connected to a Syscomoram computer system which calculated the following parameters: work, resistances, tension-time index and contractility indices. Left ventricular ejection fraction and volumes were obtained from cineangiograms performed 30 min before drug infusion and at the end of the third infusion plateau. AR-C 239 produces a dose-dependent fall in systemic blood pressure (r = 0.539, n = 33, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Antagonistas Adrenérgicos alfa/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Hemodinâmica/efeitos dos fármacos , Isoquinolinas/uso terapêutico , Piperazinas , Antagonistas Adrenérgicos alfa/administração & dosagem , Antagonistas Adrenérgicos alfa/farmacologia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Feminino , Humanos , Infusões Intravenosas , Isoquinolinas/administração & dosagem , Isoquinolinas/farmacologia , Masculino , Pessoa de Meia-Idade
20.
Clin Cardiol ; 13(11): 773-80, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2272133

RESUMO

A special form of complex coronary angioplasty is represented by the extension of indications for percutaneous transluminal coronary angioplasty (PTCA) to patients with multivessel disease (MVD) for whom surgery is not indicated, and thus for whom surgical standby is not available. Over a two-year period, 254 consecutive coronary patients with multivessel disease underwent PTCA under such conditions. These patients could not benefit from surgery for various reasons. Of the 612 arteries involved, 155 were occluded, 47 had been previously bypassed. A distal nonbypassable lesion in one of the three major arteries was found in 244 patients, 61 had suffered from a previous infarct, 24 demonstrated an ejection fraction below 0.40, and in 19 a single patent vessel was found. Fifteen patients were in cardiogenic shock and 69 procedures were undertaken for unstable angina. Of this latter group, 25 emergency PTCA were attempted for refractory unstable angina, and 44 additional emergency procedures were directed to the treatment of acute infarct. A total of 40 intra-aortic counterpulsations were needed. As far as possible the procedure aimed at full revascularization. Immediate outcome is strongly affected by the clinical context, and despite a rather constant initial success rate (88-95%), the procedural mortality (directly related or not) can change dramatically with clinical factors.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Angioplastia Coronária com Balão , Doença das Coronárias/terapia , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Angioplastia Coronária com Balão/mortalidade , Emergências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Prognóstico , Fatores de Risco
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