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2.
J Viral Hepat ; 19(12): 872-80, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23121366

RESUMO

A new hepatitis B virus (HBV) protein, hepatitis B splice-generated protein (HBSP), has been detected in liver biopsy specimens from patients with chronic active hepatitis. The aim of this study was to characterize the phenotype and functions of peripheral HBSP-specific T cells and to determine whether these T-cell responses may be implicated in liver damage or viral control. Two groups of patients were studied: HBV-infected patients with chronic active hepatitis and HBV-infected patients who were inactive carriers of hepatitis B surface antigen. HBSP-specific T-cell responses were analysed ex vivo and after in vitro stimulation of peripheral blood mononuclear cells. Soluble cytokines and chemokines were analysed in sera and in cell culture supernatants. Few HBSP- or capsid-specific T-cell responses were detected in patients with chronic active hepatitis whereas frequency of HBV-specific T cells was significantly higher in inactive carrier patients. HBSP activated CD8+ and CD4+ T cells that recognized multiple epitopes and secreted inflammatory cytokines. The IL-12 level was significantly lower in sera from asymptomatic carrier patients compared to patients with chronic active hepatitis. IL-12 and IP-10 levels in the sera were significantly and independently correlated with both alanine amino transferase and HBV DNA levels. Our results show that the HBSP protein activates cellular immune responses in HBV-infected patients but has probably no prominent role in liver damage. The pattern of cytokines and chemokines in sera was linked to HBV viral load and was consistent with the level of inflammation during chronic hepatitis.


Assuntos
Citocinas/metabolismo , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Fígado/patologia , Linfócitos T/imunologia , Proteínas Virais/imunologia , Adulto , Idoso , Alanina Transaminase/sangue , Portador Sadio/imunologia , Portador Sadio/virologia , Células Cultivadas , Citocinas/sangue , Feminino , Hepatite B Crônica/virologia , Humanos , Leucócitos Mononucleares/imunologia , Fígado/virologia , Masculino , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia , Carga Viral , Adulto Jovem
3.
Minerva Cardioangiol ; 60(2): 157-66, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22495164

RESUMO

Percutaneous coronary intervention of degenerated saphenous vein grafts remains relatively high risk when compared to native vessel interventions, despite advances in pharmacotherapy and embolic protection. This article discusses the phenomenon of distal embolization that seems to plague saphenous vein graft interventions, reviews device-based strategies for embolic protection, and offers a perspective on the utility of percutaneous saphenous vein graft intervention in both elective and acute settings.


Assuntos
Ponte de Artéria Coronária , Dispositivos de Proteção Embólica , Embolia/prevenção & controle , Embolização Terapêutica/instrumentação , Embolização Terapêutica/métodos , Veia Safena/transplante , Stents , Embolia/tratamento farmacológico , Humanos
4.
Rev Sci Instrum ; 79(2 Pt 2): 02A907, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18315162

RESUMO

The SPIRAL2 project, currently under construction at GANIL, will include an isotope separator on line based facility for the production and acceleration of radioactive ion beams. A superconducting linear accelerator will accelerate 5 mA deuterons up to 40 MeV and 1 mA heavy ions up to 14.5 MeV/u. These primary beams will be used to bombard both thick and thin targets. We are investigating three different techniques to produce the radioactive ion beams: (1) the neutron induced fission of uranium carbide, (2) the direct interaction of deuterons in a uranium carbide target, and (3) the interaction of a heavy ion beam with a target. All these production systems will be coupled to an ion source. Four kinds of ion sources are foreseen for the ionization of the radioactive atoms: an electron cyclotron resonance ion source, a surface ionization ion source, a forced electron beam induced arc discharge ion source, and a laser ion source depending on the characteristics of the desired radioactive ion beam in terms of intensity, efficiency, purity, etc. A presentation of the SPIRAL2 project and of the different production systems is given.

5.
Gastroenterol Clin Biol ; 32(1 Pt 2): S34-41, 2008 Jan.
Artigo em Francês | MEDLINE | ID: mdl-18662608

RESUMO

Parenteral and community-acquired routes of contamination sanguins of hepatitis B virus (HBV) explain its frequency (9 to 20%) in dialysis patients and kidney recipients. In dialysis, HBV infection has few impact on morbidity and mortality; by contrast, in kidney recipients HBV: 1. reduces the allograft survival; 2. the patients survival in association with a frequent and rapid evolution to cirrhosis and hepatocellular carcinoma or rare cholestatic fibrosis. Finally, cirrhosis contra-indicates renal transplantation alone given its poor short-term prognosis and a combined liver-kidney transplantation has to be discussed. Thus, it is necessary to evaluate the liver severity of the liver disease. The treatement of HBV in allograft recipients and dialysis is based on nucleos(t)idic analogues like in the general population with the same advantages and questions. The variations of the immune status either in an HBV-infected patients at the induction or at the reduction of chemotherapies (solid tumors or hemopathies) or allograft transplantation may result in two, potentially severe, events in miror: a reactivation or a spontaneous discontinuation of viral replication (seronconversion). These risks evidence that any HBs Ag carrier exposed to immune suppression has to be diagnosed, evaluated for viral replication and underlying liver disease and has to be treated by a so-called pre-emptive treatment based on analogues.


Assuntos
Hepatite B Crônica/etiologia , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/prevenção & controle , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/prevenção & controle , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/prevenção & controle , Humanos , Hospedeiro Imunocomprometido , Transplante de Rim/efeitos adversos , Diálise Renal/efeitos adversos
6.
Virologie (Montrouge) ; 12(2): 87-94, 2008 Apr 01.
Artigo em Francês | MEDLINE | ID: mdl-36131428

RESUMO

Occult hepatitis B virus (HBV) infection is a peculiar form of chronic viral infection identified since the early 80's and can be defined as the presence of HBV DNA in the serum and/or in the liver tissue of patients negative for the HBV surface antigen (HBsAg) using usual serological tests. The data about the prevalence of occult HBV infection are contrasting and the reported prevalences in various categories of individuals are highly diverse. The molecular basis of the occult HBV infection is the covalently closed-circular DNA (cccDNA) that persists in the cell nuclei and that serves as a template for gene transcription. The physiopathology of occult HBV infection is still unclear. However, the available data suggest that the host's immune response, the co-infections with other infectious agents and epigenetic factors may play important roles in indicing the occult status. The clinical relevance of occultHBVinfection remains debated but it may impact in four clinical contexts: 1) the transmission of the infection by blood transfusion or organ transplantation; 2) the acute reactivation when an immunosuppressive status occurs mainly in patients with isolated anti-HBc (chemotherapy, transplantations, immunodepression, new immunosuppressive therapy as anti-CD20 or anti TNF); 3) the potent but non proved progression of liver fibrosis in HCV infected patients or in patients with cryptogenetic liver disease; and, 4. the risk factor for hepatocellular carcinoma development.

8.
Arch Mal Coeur Vaiss ; 99 Spec no.3: 23-5, 2006 Feb.
Artigo em Francês | MEDLINE | ID: mdl-16553240

RESUMO

The accumulation of evidence of efficacy and tolerance led to the FDA approval of bivalirudine in the United States and it has progressively replaced the use of unfractionated heparin in its traditional indication in the catheter laboratory of the Washington Hospital Center. This change has probably contributed to the reduction of bleeding complications observed in this institution. The experience acquired also showed a reduced risk of enzyme rises after the procedure. The use of bivalirudine in conditions comparable to those of the REPLACE II trial confirms that anti GPIIb/IIIa molecules should be reserved for extreme circumstances rather than be systematically associated with heparin, so significantly reducing the cost of the interventional procedures.


Assuntos
Angioplastia Coronária com Balão , Fibrinolíticos/uso terapêutico , Stents , Trombose/prevenção & controle , Antitrombinas/uso terapêutico , Hirudinas , Humanos , Fragmentos de Peptídeos/uso terapêutico , Hemorragia Pós-Operatória/etiologia , Proteínas Recombinantes/uso terapêutico , Troponina I/sangue
9.
Cancer Res ; 59(16): 3875-9, 1999 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10463573

RESUMO

Mutations in the adenomatous polyposis coli gene or activating mutations in the beta-catenin gene itself are thought to be responsible for the excessive beta-catenin signaling involved in intestinal carcinogenesis. We generated transgenic mice that expressed large amounts of a NH2-terminally truncated mutant beta-catenin (deltaN131beta-catenin) in the intestine. These mice had multifocal dysplastic lesions in the small intestine, reminiscent of the early lesions observed in the mouse models of familial adenomatous polyposis. The number of apoptotic cells in the villi of these transgenic mice was 3-4-fold higher than in nontransgenic mice. Expression of the truncated beta-catenin mutant in the kidney led to the development of severe polycystic kidney disease. Our findings support the concept that deregulation of the beta-catenin signaling pathway is the major oncogenic consequence of adenomatous polyposis coli mutations in intestinal neoplasia.


Assuntos
Adenoma/genética , Proteínas do Citoesqueleto/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Intestinais/genética , Mutação , Transativadores , Polipose Adenomatosa do Colo/genética , Animais , Caderinas/genética , Enteropatias/genética , Camundongos , Camundongos Transgênicos , beta Catenina
10.
Phys Med Biol ; 61(19): 6935-6952, 2016 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-27617585

RESUMO

Current preclinical dosimetric models often fail to take account of the complex nature of absorbed dose distribution typical of in vitro clonogenic experiments in targeted radionuclide therapy. For this reason, clonogenic survival is often expressed as a function of added activity rather than the absorbed dose delivered to cells/cell nuclei. We designed a multi-cellular dosimetry model that takes into account the realistic distributions of cells in the Petri dish, for the establishment of survival curves as a function of the absorbed dose. General-purpose software tools were used for the generation of realistic, randomised 3D cell culture geometries based on experimentally determined parameters (cell size, cell density, cluster density, average cluster size, cell cumulated activity). A mixture of Monte Carlo and analytical approaches was implemented in order to achieve as accurate as possible results while reducing calculation time. The model was here applied to clonogenic survival experiments carried out to compare the efficacy of Betalutin®, a novel 177Lu-labelled antibody radionuclide conjugate for the treatment of non-Hodgkin lymphoma, to that of 177Lu-labelled CD20-specific (rituximab) and non-specific antibodies (Erbitux) on lymphocyte B cells. The 3D cellular model developed allowed a better understanding of the radiative and non-radiative processes associated with cellular death. Our approach is generic and can also be applied to other radiopharmaceuticals and cell distributions.


Assuntos
Antineoplásicos/uso terapêutico , Lutécio/uso terapêutico , Linfoma não Hodgkin/radioterapia , Modelos Biológicos , Compostos Radiofarmacêuticos/uso terapêutico , Rituximab/uso terapêutico , Antineoplásicos/farmacocinética , Humanos , Lutécio/farmacocinética , Linfoma não Hodgkin/metabolismo , Método de Monte Carlo , Radiometria/métodos , Compostos Radiofarmacêuticos/farmacocinética , Rituximab/farmacocinética , Software , Distribuição Tecidual , Células Tumorais Cultivadas
11.
Aliment Pharmacol Ther ; 44(5): 505-13, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27407002

RESUMO

BACKGROUND: There is a relationship between liver stiffness measurement (LSM) and outcome of HCV patients. AIM: To evaluate the performance of LSM to predict outcome of HCV patients at risk of liver-related complication. METHODS: We established a retrospective longitudinal cohort of 341 HCV patients with unequivocal cirrhosis. All underwent LSM and were followed from September 2006 to July 2015. Outcome measure was a composite end-point of end-stage liver disease (ESLD) and/or hepatocellular carcinoma (HCC). Cox models and areas under receiver operating characteristic (AUROC) curves were used to evaluate independent risk factors of outcome. RESULTS: Overall, LSM was below the 12.5 kPa threshold in 129 (37.8%) patients, including three-fourth and one-third of patients with or without a sustained virological response respectively. Liver disease progressed in 136 (39.9%) patients after a median observational period of 23.5 months. Older age, male gender, alcohol use disorders, metabolic syndrome and LSM were independent risk factors of liver disease progression. Age, alcohol use disorders and LSM were independently associated with ESLD. Age, gender and metabolic syndrome, but not LSM, were associated with HCC. The AUROC curves for disease progression, ESLD and HCC were 0.67, 0.70 and 0.58 respectively. Patients with a liver stiffness >12.5 kPa were at the highest risk of liver disease progression; below 12.5 kPa, liver stiffness was not discriminant. CONCLUSION: Liver stiffness measurement is not a surrogate of disease progression of HCV patients with cirrhosis. HCV patients with cirrhosis should undergo the recommended follow-up, regardless of liver stiffness measurement.


Assuntos
Progressão da Doença , Técnicas de Imagem por Elasticidade/tendências , Doença Hepática Terminal/diagnóstico , Hepatite C Crônica/diagnóstico , Hospitalização/tendências , Adulto , Idoso , Doença Hepática Terminal/complicações , Doença Hepática Terminal/terapia , Feminino , Hepatite C Crônica/complicações , Hepatite C Crônica/terapia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Cirrose Hepática/terapia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
12.
Biochim Biophys Acta ; 657(1): 84-93, 1981 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-6260201

RESUMO

Interactions between phosphorylase kinase (ATP:phosphorylase-b phosphotransferase, EC 2.7.1.38) and calmodulin were studied with pure preparations of muscle phosphorylase kinase, and with crude extracts from muscles of control (C57 Black) and deficient (ICR/IAn) mice, which lack muscle phosphorylase kinase activity. Calmodulin was determined by its ability to stimulate a calmodulin-dependent phosphodiesterase. The amount of calmodulin bound to phosphorylase kinase in muscle extract was estimated to a maximum of 30% of the total amount of calmodulin. In the muscle of the deficient strain a decrease of 35% in the total amount of calmodulin was observed. This correlates with the absence of the calmodulin fraction specifically bound to phosphorylase kinase. From sucrose gradient studies we demonstrated that in the presence of Ca2+ the amount of calmodulin bound to phosphorylase kinase was enhanced, compared to the control in the presence of EGTA. This observation was made both in crude extracts and in pure phosphorylase kinase preparations. Sucrose gradient also showed that muscle phosphorylase kinase can be dissociated to low molecular species when extracts are made in the presence of Ca+; this dissociation was found to be related to a Ca2+-dependent proteolytic effect.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Calmodulina/metabolismo , Músculos/enzimologia , Diester Fosfórico Hidrolases/metabolismo , Fosforilase Quinase/metabolismo , Animais , Centrifugação com Gradiente de Concentração , Técnicas In Vitro , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Fosforilase Quinase/deficiência , Ligação Proteica
13.
Circulation ; 101(19): 2227-30, 2000 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-10811587

RESUMO

BACKGROUND: The effects of endovascular irradiation on uninjured reference segments during the treatment of in-stent restenosis are unknown. METHODS AND RESULTS: In the Washington Radiation for In-Stent restenosis Trial (WRIST), patients with in-stent restenosis were first treated with conventional catheter-based techniques and then randomized (blinded) to receive either gamma-irradiation ((192)Ir) or a placebo (dummy seeds). We identified all patients in whom the active (n=19) or dummy seeds (n=19) extended >10 mm proximal and distal to the in-stent restenosis lesion. Serial (postirradiation and follow-up) external elastic membrane (EEM), lumen, and plaque and media (EEM-lumen) areas were measured (using intravascular ultrasound) every 1 mm over 5-mm-long reference segments that were 6 to 10 mm proximal and distal to the in-stent restenosis lesion. During follow-up, a similar small increase occurred in the plaque and media area in the proximal and distal reference segments in both (192)Ir and placebo patients. However, in the (192)Ir patients, an increase in both proximal and distal EEM area occurred; as a result, no change in lumen area occurred. Conversely, in the placebo patients, the proximal reference EEM area decreased, and no change occurred in the distal reference EEM area; this contributed to a decrease in lumen area. CONCLUSIONS: There was no evidence of a deleterious effect of gamma-irradiation on angiographically normal uninjured reference segments in the first 6 months after the treatment of in-stent restenosis.


Assuntos
Doença das Coronárias/radioterapia , Vasos Coronários/efeitos da radiação , Stents , Doença das Coronárias/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Método Duplo-Cego , Tecido Elástico/diagnóstico por imagem , Tecido Elástico/efeitos da radiação , Humanos , Recidiva , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia de Intervenção
14.
Circulation ; 104(8): 856-9, 2001 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-11514368

RESUMO

BACKGROUND: The efficacy of coronary gamma-irradiation in preventing recurrent in-stent restenosis (ISR) is well established. However, brachytherapy may be less effective in very long, diffuse ISR lesions. METHODS AND RESULTS: We used serial intravascular ultrasound (IVUS) to study patients with long, diffuse ISR lesions (length, 36 to 80 mm) who were enrolled in (1) Long WRIST (Washington Radiation In-Stent Restenosis Trial), a double-blind, placebo-controlled trial of intracoronary gamma-irradiation (15 Gy at 2 mm from the source) and (2) high-dose (HD) Long WRIST, a registry that used a dose prescription of 18 Gy at 2 mm from the source. IVUS was performed using automated pullback (0.5 mm/s). Stent, lumen, and intimal hyperplasia were measured at 2-mm intervals. Complete postintervention and follow-up IVUS imaging was available in 30 irradiated and 34 placebo patients from Long WRIST and in 25 patients from HD Long WRIST. Stent length was longer in HD Long WRIST than in placebo or treated patients in Long WRIST (P=0.0064 and P=0.0125, respectively). Otherwise, baseline measurements were similar. At follow-up, the minimum lumen area was largest in the HD Long WRIST patients (4.0+/-1.4 mm(2)); areas were 2.9+/-1.0 mm(2) in irradiated patients in Long WRIST and 1.9+/-1.1 mm(2) in placebo patients in Long WRIST (P<0.005 for all comparisons). CONCLUSIONS: - Serial IVUS analysis shows that gamma-irradiation reduces recurrent in-stent neointimal hyperplasia in long, diffuse ISR lesions; however, it is even more effective when given at a higher dose.


Assuntos
Raios gama/uso terapêutico , Oclusão de Enxerto Vascular/prevenção & controle , Revascularização Miocárdica , Stents , Ultrassonografia de Intervenção , Braquiterapia/métodos , Doença das Coronárias/cirurgia , Relação Dose-Resposta à Radiação , Método Duplo-Cego , Oclusão de Enxerto Vascular/classificação , Oclusão de Enxerto Vascular/diagnóstico , Humanos , Pessoa de Meia-Idade , Revascularização Miocárdica/efeitos adversos , Revascularização Miocárdica/métodos , Fatores de Risco , Prevenção Secundária , Stents/efeitos adversos , Resultado do Tratamento , Grau de Desobstrução Vascular/efeitos da radiação
15.
Circulation ; 99(24): 3149-54, 1999 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-10377078

RESUMO

BACKGROUND: Pathological and intravascular ultrasound (IVUS) studies have documented arterial remodeling during atherogenesis. However, the impact of this remodeling process on the long-term outcome after percutaneous intervention is unknown. METHODS AND RESULTS: We used preintervention IVUS to define positive and negative/intermediate remodeling in a total of 777 lesions in 715 patients treated with nonstent techniques. Positive remodeling (lesion external elastic membrane area greater than average reference) was present in 313 lesions; intermediate/negative remodeling (lesion external elastic membrane area less than or equal to reference) was present in the other 464. Baseline clinical and angiographic characteristics were similar, except for a slightly higher percentage of insulin-dependent diabetic patients (10.2% versus 6.1%; P=0.054) in the negative/intermediate-remodeling group. Angiographic success and in-hospital and short-term complications were comparable in the 2 groups. There was no significant correlation between remodeling (as a continuous variable) and final lumen area (r=0.06) or final lesion plaque burden (r=0.17). At 18+/-13 months of clinical follow-up, both groups had similar rates of death and Q-wave myocardial infarction: 3.4% and 2.5% for the negative/intermediate-remodeling group versus 2.7% and 2.7% for the positive-remodeling group. However, the target-lesion revascularization (TLR) rate was 20.2% for the negative/intermediate-remodeling group versus 31.2% for the positive-remodeling group (P=0.007), and remodeling, as a continuous variable, was strongly correlated with probability of TLR (P=0.0001). By multivariable logistic regression analysis, diabetes (OR=2.3), left anterior descending artery location (OR=1.8), and remodeling (OR=5.9) were independent predictors of TLR. CONCLUSIONS: Positive lesion-site remodeling is associated with a higher long-term TLR after a nonstent interventional procedure. Thus, long-term clinical outcome appears to be determined in part by preintervention lesion characteristics.


Assuntos
Angioplastia com Balão , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/cirurgia , Ultrassonografia de Intervenção , Idoso , Angiografia Coronária , Doença das Coronárias/terapia , Ecocardiografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Complicações Pós-Operatórias , Stents , Resultado do Tratamento
16.
Circulation ; 101(6): 604-10, 2000 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10673251

RESUMO

BACKGROUND: Elevation of serum creatine kinase MB fraction (CK-MB) after percutaneous coronary interventions has been associated with early and late mortality; however, the pathogenesis of CK-MB elevation is still unknown. We hypothesized that CK-MB elevation was related to atherosclerotic plaque burden as assessed by preintervention intravascular ultrasound (IVUS). METHODS AND RESULTS: We studied 2256 consecutive patients who underwent intervention of 2780 native coronary lesions and had complete high-quality preintervention IVUS imaging in the era before routine use of platelet glycoprotein IIb/IIIa inhibitors. Patients were divided into 3 groups: CK-MB within normal range (1675 patients; 2061 lesions); CK-MB elevation 1 to 5 times upper limit of normal (292 patients; 355 lesions); and CK-MB elevation > or = 5 times upper limit of normal (289 patients; 364 lesions). Qualitative angiographic lesion morphology and quantitative analysis were similar among the 3 groups. On preintervention IVUS, progressively more reference segment and lesion site plaque burden and lesion site calcium occurred in the groups with CK-MB elevation. Positive remodeling was more common in lesions with CK-MB elevation. As levels of CK-MB increased, cross-sectional narrowing (percentage plaque burden) increased, both at the reference site (mean cross-sectional narrowing values were 45.1%, <49.3%, and <52.2% for normal CK-MB, 1 to 5 times upper limit of normal, and > or =5 times upper limit of normal groups, respectively; P=0.03) and at the lesion site (81.9%, <85.4%, and <87.1%, respectively; P=0.04). Multivariate analysis indicated that de novo lesions, atheroablative technique, plaque burden at the lesion and reference segments, and final minimal lumen diameter were independent predictors of CK-MB elevation. CONCLUSIONS: CK-MB elevation correlates with a greater atherosclerotic plaque burden. CK-MB elevation after intervention may be a marker of diffuse atherosclerotic disease or a consequence of catheter-based intervention in more diseased arteries or both.


Assuntos
Angioplastia com Balão , Doença da Artéria Coronariana , Creatina Quinase/sangue , Idoso , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/cirurgia , Feminino , Humanos , Isoenzimas , Masculino , Pessoa de Meia-Idade , Ultrassonografia de Intervenção
17.
Circulation ; 102(1): 7-10, 2000 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-10880407

RESUMO

BACKGROUND: Intravascular ultrasound analysis has assessed mechanisms of lumen enlargement after nonstent interventions, but not after stenting. METHODS AND RESULTS: Preintervention and postintervention intravascular ultrasound was used to study 25 de novo native coronary lesions treated with single MultiLink stents without preatheroablation. External elastic membrane, lumen, and plaque and media (P&M) areas were measured every 1 mm to include the lesion and reference segments that were 5 mm proximal and distal to it. Lesion mean lumen area increased from 4.0+/-1.0 mm(2) before the intervention to 8.8+/-2.0 mm(2) after the intervention (P<0.0001) as a result of an increase in mean external elastic membrane area (14. 2+/-2.7 to 16.1+/-3.0 mm(2), P<0.0001) and a decrease in mean P&M area (10.2+/-2.2 to 7.2+/-1.8 mm(2), P<0.0001). The decrease in lesion P&M was accompanied by an increase in both proximal reference mean P&M (7.0+/-1.9 to 8.4+/-2.0 mm(2), P<0.0001) and distal reference mean P&M (5.8+/-2.1 to 7.2+/-2.1 mm(2), P<0.0001). Volumetric analysis showed an axial redistribution of plaque away from the center of the lesion toward the reference segments to increase the plaque burden in both the proximal and distal reference segments. Total (lesion plus reference) mean P&M decreased from 8. 6+/-2.1 to 7.5+/-1.8 mm(2) (P<0.0001). CONCLUSIONS: The mechanisms of lumen enlargement after stenting involved (1) significant axial redistribution of plaque from the lesion into the reference segments, (2) vessel expansion, and (3) either plaque embolization or compression.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/terapia , Revascularização Miocárdica/métodos , Complicações Pós-Operatórias/diagnóstico por imagem , Stents , Idoso , Estudos de Coortes , Angiografia Coronária , Circulação Coronária , Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Revascularização Miocárdica/instrumentação , Ultrassonografia
18.
Circulation ; 101(16): 1895-8, 2000 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-10779453

RESUMO

BACKGROUND: Intracoronary gamma-radiation therapy reduces recurrent in-stent restenosis (ISR). This study, BETA WRIST (Washington Radiation for In-Stent restenosis Trial) was designed to examine the efficacy and safety of the beta-emitter 90-yttrium for the prevention of recurrent ISR. METHODS AND RESULTS: A total of 50 consecutive patients with ISR in native coronaries underwent percutaneous transluminal coronary angioplasty, laser angioplasty, rotational atherectomy, and/or stent implantation. Afterward, a segmented balloon catheter was positioned and automatically loaded with a 90-yttrium, 0.014-inch source wire that was 29 mm in length to deliver a dose of 20.6 Gy at 1.0 mm from the balloon surface. In 17 patients, manual stepping of the radiation catheter was necessary for lesions >25 mm in length. The radiation was delivered successfully to all patients, with a mean dwell time of 3.0+/-0.4 minutes. Fractionation of the dose due to ischemia was required in 11 patients. At 6 months, the binary angiographic restenosis rate was 22%, the target lesion revascularization rate was 26%, and the target vessel revascularization rate was 34%; all rates were significantly lower than those of the placebo group of gamma-WRIST. CONCLUSIONS: beta-Radiation with a 90-yttrium source used as adjunct therapy for patients with ISR results in a lower-than-expected rate of angiographic and clinical restenosis.


Assuntos
Angioplastia Coronária com Balão , Braquiterapia , Doença das Coronárias/radioterapia , Stents , Adulto , Idoso , Partículas beta , Constrição Patológica , Doença das Coronárias/patologia , Vasos Coronários/patologia , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos , Recidiva , Túnica Íntima/patologia , Radioisótopos de Ítrio/uso terapêutico
19.
Circulation ; 101(21): 2484-9, 2000 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-10831522

RESUMO

BACKGROUND: Atheroablation yields improved clinical results for balloon angioplasty (percutaneous transluminal coronary angioplasty, PTCA) in the treatment of diffuse in-stent restenosis (ISR). METHODS AND RESULTS: We compared the mechanisms and clinical results of excimer laser coronary angioplasty (ELCA) versus rotational atherectomy (RA), both followed by adjunct PTCA; 119 patients (158 ISR lesions) were treated with ELCA+PTCA and 130 patients (161 ISR lesions) were treated with RA+PTCA. Quantitative coronary angiographic and planar intravascular ultrasound (IVUS) measurements were performed routinely. In addition, volumetric IVUS analysis to compare the mechanisms of lumen enlargement was performed in 28 patients with 30 lesions (16 ELCA+PTCA, 14 RA+PTCA). There were no significant between-group differences in preintervention or final postintervention quantitative coronary angiographic or planar IVUS measurements of luminal dimensions. Angiographic success and major in-hospital complications with the 2 techniques were also similar. Volumetric IVUS analysis showed significantly greater reduction in intimal hyperplasia volume after RA than after ELCA (43+/-14 versus 19+/-10 mm(3), P<0.001) because of a significantly higher ablation efficiency (90+/-10% versus 76+/-12%, P = 0.004). However, both interventional strategies had similar long-term clinical outcome; 1-year target lesion revascularization rate was 26% with ELCA+PTCA versus 28% with RA+PTCA (P = NS). CONCLUSIONS: Despite certain differences in the mechanisms of lumen enlargement, both ELCA+PTCA and RA+PTCA can be used to treat diffuse ISR with similar clinical results.


Assuntos
Angioplastia com Balão a Laser , Aterectomia Coronária/métodos , Doença das Coronárias/terapia , Stents , Angioplastia Coronária com Balão , Angiografia Coronária , Doença das Coronárias/prevenção & controle , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento , Ultrassonografia de Intervenção
20.
Circulation ; 100(3): 256-61, 1999 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-10411849

RESUMO

BACKGROUND: Angiography is limited in determining the anatomic severity of coronary artery stenoses. Clinical decision-making in patients with symptoms and intermediate lesions remains challenging. METHODS AND RESULTS: The current analysis included 300 patients (357 intermediate native artery lesions) in whom intervention was deferred based on intravascular ultrasound (IVUS) findings. Standard clinical, angiographic, and IVUS parameters were collected. Patients were followed for >1 year. Events occurred in 24 patients (8%). They included 2 cardiac deaths, 4 myocardial infarctions, and 18 target-lesion revascularizations (TLR; 12 percutaneous transluminal coronary angiographies and 6 coronary artery bypass grafts; only 3 TLRs occurred within 6 months after the IVUS study). All significant univariate clinical, angiographic, and IVUS parameters (P<0.05) were tested in multivariate models. These included diabetes mellitus, IVUS lesion lumen area, maximum lumen diameter, minimum lumen diameter, plaque area, plaque burden, and area stenosis (AS). No angiographic measurement was significant at P<0.05. The only independent predictors of an event (death, myocardial infarction, or TLR) were IVUS minimum lumen area and AS. The only independent predictors of TLR were diabetes mellitus, IVUS minimum lumen area, and AS. In 248 lesions with a minimum lumen area >/=4.0 mm(2), the event rate was only 4.4% and the TLR rate 2.8%. CONCLUSIONS: Long-term follow-up after IVUS-guided deferred interventions in patients with de novo intermediate native artery lesions showed a low event rate. In patients with a minimum lumen area >/=4.0 mm(2), the event rate was especially low. IVUS imaging is an acceptable alternative to physiological assessment in these patients.


Assuntos
Angioplastia Coronária com Balão , Vasos Coronários/patologia , Ultrassonografia/métodos , Angiografia Coronária , Doença das Coronárias/diagnóstico , Doença das Coronárias/prevenção & controle , Vasos Coronários/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Fatores de Tempo
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