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1.
Health Phys ; 115(1): 185-191, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29787445

RESUMO

Estimation of the dose received by accidentally irradiated victims is based on a tripod: clinical, biological, and physical dosimetry. The DosiKit system is an operational and mobile biodosimetry device allowing the measurement of external irradiation directly on the site of a radiological accident. This tool is based on capillary blood sample and hair follicle collection. The aim is to obtain a whole-body and local-surface dose assessment. This paper is about the technical evaluation of the DosiKit; the analytical process and scientific validation are briefly described. The Toulon exercise scenario was based on a major accident involving the reactor of a nuclear attack submarine. The design of the scenario made it impossible for several players (firefighters, medical team) to leave the area for a long time, and they were potentially exposed to high dose rates. The DosiKit system was fully integrated into a deployable radiological emergency laboratory, and the response to operational needs was very satisfactory.


Assuntos
Sangue/efeitos da radiação , Cabelo/química , Imunoensaio/instrumentação , Laboratórios/normas , Lesões por Radiação/prevenção & controle , Liberação Nociva de Radioativos/prevenção & controle , Radiometria/instrumentação , França , Cabelo/efeitos da radiação , Humanos
2.
Acta Cardiol ; 73(3): 248-255, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28847218

RESUMO

BACKGROUND: With more than 15,000 implanted patients worldwide and a survival rate of 80% at 1-year and 59% at 5-years, left ventricular assist device (LVAD) implantation has become an interesting strategy in the management of heart failure patients who are resistant to other kinds of treatment. There are limited data in the literature on the change over time of exercise capacity in LVAD patients, as well as limited knowledge about the beneficial effects that rehabilitation might have on these patients. Therefore, the aim of our study was to evaluate the evolution of exercise capacity on a cohort of patients implanted with the same device (HeartWare©) and to analyse the potential impact of rehabilitation. METHODS: Sixty-two patients implanted with a LVAD between June 2011 and June 2015 were screened. Exercise capacity was evaluated by cardiopulmonary exercise testing at 6 weeks, 6 and 12 months after implantation. RESULTS: We have observed significant differences in the exercise capacity and evolution between the trained and non-trained patients. Some of the trained patients nearly normalised their exercise capacity at the end of the rehabilitation programme. CONCLUSIONS: Exercise capacity of patient implanted with a HeartWare© LVAD increased in the early period after implantation. Rehabilitation allowed implanted patients to have a significantly better evolution compared to non-rehabilitated patients.


Assuntos
Reabilitação Cardíaca/métodos , Terapia por Exercício/métodos , Insuficiência Cardíaca/reabilitação , Coração Auxiliar , Teste de Esforço , Tolerância ao Exercício/fisiologia , Feminino , Seguimentos , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo
3.
Radiat Res ; 187(3): 273-286, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28218888

RESUMO

The utility of early-phase (≤5 days) radiation-induced clinical signs and symptoms (e.g., vomiting, diarrhea, erythema and changes in blood cell counts) was examined for the prediction of later occurring acute radiation syndrome (ARS) severity and the development of medical management strategies. Medical treatment protocols for radiation accident victims (METREPOL) was used to grade ARS severities, which were assigned response categories (RCs). Data on individuals (n = 191) with mild (RC1, n = 45), moderate (RC2, n = 19), severe (RC3, n = 20) and fatal (RC4, n = 18) ARS, as well as nonexposed individuals (RC0, n = 89) were generated using either METREPOL (n = 167) or the system for evaluation and archiving of radiation accidents based on case histories (SEARCH) database (n = 24), the latter comprised of real-case descriptions. These data were converted into tables reflecting clinical signs and symptoms, and submitted to eight teams representing five participating countries. The teams were comprised of medical doctors, biologists and pharmacists with subject matter expertise. The tables comprised cumulated clinical data from day 1-3 and day 1-5 postirradiation. While it would have reflected a more realistic scenario to provide the data to the teams over the course of a 3- or 5-day period, the logistics of doing so proved too challenging. In addition, the team members participating in this exercise chose to receive the cumulated reports of day 1-3 and 1-5. The teams were tasked with predicting ARS incidence, ARS severity and the requirement for hospitalization for multiple cases, as well as providing the certainty of their diagnosis. Five of the teams also performed dose estimates. The teams did not employ harmonized methodologies, and the expertise among the members varied, as did the tools used and the means of analyzing the clinical data. The earliest report time was 3 h after the tables were sent to the team members. The majority of cases developing ARS (89.6% ± 3.3 SD) and requiring hospitalization (88.8% ± 4.6 SD) were correctly identified by all teams. Determination of ARS severity was particularly challenging for RC2-3, which was systematically overestimated. However, RC4 was correctly predicted at 94-100% by all teams. RC0 and RC1 ARS severities were more difficult to discriminate. When reported RCs (0-1 and 3-4) were merged, on average 89.6% (±3.3 SD) of all cases could be correctly classified. Comparisons on frequency distributions revealed no statistically significant differences among the following: 1. reported ARS from different teams (P > 0.2); 2. cases generated based on METREPOL or SEARCH (P > 0.5); or 3. results reported at day 3 and 5 postirradiation (P > 0.1). Dose estimates of all teams increased significantly along with ARS severity (P < 0.0001) as well as with dose estimates generated from dicentric chromosomal-aberration measurements available for SEARCH cases (P < 0.0001). In summary, early-phase radiation-induced clinical signs and symptoms proved to be useful for rapid and accurate assessment, with minor limitations, toward predicting life-threatening ARS severity and developing treatment management strategies.


Assuntos
Síndrome Aguda da Radiação/diagnóstico , Incidentes com Feridos em Massa , Síndrome Aguda da Radiação/terapia , Hospitalização , Humanos , Agências Internacionais , Doses de Radiação , Liberação Nociva de Radioativos , Fatores de Tempo
4.
Health Phys ; 111(2): 223-6, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27356069

RESUMO

The French Defense Radiation Protection Service (SPRA) is an institution of the French Armed Forces (SSA) that provides technical support in radiation protection matters for French military units. It provides services for the armed forces and when necessary for the national public health system. The aim of this note is to describe the variety of services provided by the SPRA in France and abroad, not only in a military context but also in the broader field of radiation protection.


Assuntos
Defesa Civil/organização & administração , Descontaminação/métodos , Medicina Militar/organização & administração , Objetivos Organizacionais , Lesões por Radiação/diagnóstico , Lesões por Radiação/prevenção & controle , Serviços Médicos de Emergência/organização & administração , França , Modelos Organizacionais , Exposição à Radiação/análise , Exposição à Radiação/prevenção & controle
5.
Cancer Chemother Pharmacol ; 49(4): 287-93, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11914907

RESUMO

PURPOSE: KRN7000 is a novel anticancer agent, acting through stimulation of the immune system. The first clinical trial with this agent, which included pharmacokinetic studies, has recently been completed. The aim of the study presented here was to develop a population pharmacokinetic model for KRN7000. METHODS: Plasma concentration-time data were gathered from 24 patients enrolled in a phase I trial in which KRN7000 was administered as a weekly slow injection at doses ranging from 50 to 4800 microg/m(2). These data were used to build a pharmacokinetic model using the nonlinear mixed-effect modeling (NONMEM) program. The model was validated by performance of 200 bootstraps. RESULTS: A three-compartment model with interindividual variability on the central and two peripheral volumes of distribution (V1, V2 and V3) and on clearance (CL) adequately described the data. The final estimates were: V1 2.34 l, V2 2.61 l, V3 2.13 l, and CL 0.130 l/h. Of 24 covariates tested, including both demographic and pathophysiological factors, none showed a significant relationship with the pharmacokinetic parameters obtained. The bootstrap analysis provided parameter estimates within approximately 15% of the original estimates, indicating stability of the model. CONCLUSION: The pharmacokinetic behavior of KRN7000 in the clinical trial could be described by a three-compartment model. Hence, KRN7000 demonstrates linear pharmacokinetics over the investigated dose range. The pharmacokinetics of KRN7000 are not influenced by patient demographic or pathophysiological characteristics.


Assuntos
Antineoplásicos/farmacocinética , Galactosilceramidas/farmacocinética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos
6.
Environ Toxicol Pharmacol ; 7(4): 253-60, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21781933

RESUMO

In this study, the pH, temperature and substrate specificity for cholinesterases (ChE) assay in two bivalves was optimized: the Spanish mussel Mytilus galloprovincialis and the Asiatic clam Corbicula fluminea. The optimal values found are pH 7, 25°C, 2 mM of acetylthiocholine (ASCh) as substrate for M. galloprovincialis and pH 8, 25°C, 5 mM propionylthiocholine (PrSCh) for C. fluminea. The apparent K(m) are 30 and 70 µM for the two bivalves, respectively. In comparison with some other crustaceans and fishes, the levels of ChE activity were found to be low. The in vitro and in vivo sensitivities of the ChEs activity toward two well known pesticides: carbaryl and methylparathion (or its oxon derived form) are comparable to that observed in fishes but less than that found in crustaceans. Although further studies should be done, and other contaminants tested, the studied bivalves can be considered as interesting 'sentinel' species in the monitoring of the acute water contamination by pesticides.

7.
Ecotoxicol Environ Saf ; 32(1): 51-7, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8565877

RESUMO

The capacity of the newt to metabolize benzo(a)pyrene in vivo was investigated qualitatively and quantitatively: metabolism was found to be rapid. Treatment of bile with beta-glucuronidase and aryl-sulfatase released high proportions of diols and quinones. 3-Methylcholanthrene treatment shortened the elimination half-life of benzo(a)pyrene which was about three times shorter than the half-life found for non-3-methylcholanthrene-pretreated animals. Thus, a greater proportion of benzo(a)pyrene was converted into water-soluble products.


Assuntos
Benzo(a)pireno/farmacocinética , Poluentes Ambientais/farmacocinética , Pleurodeles/metabolismo , Animais , Bile/química , Bile/metabolismo , Biotransformação , Cromatografia Líquida de Alta Pressão , Meia-Vida , Injeções Intraperitoneais , Fígado/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Metilcolantreno/farmacologia , Radiometria
8.
Am J Cardiol ; 75(5): 383-9, 1995 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-7856533

RESUMO

Pulmonary arterial wedge pressure (PAWP) is an important marker of cardiac function. Regrettably, it requires catheterization, which can occasionally result in serious complications. A noninvasive method of estimating PAWP would thus be helpful. Recent studies have indicated that the Doppler transmitral flow velocity pattern was strongly dependent on preload and could provide an estimate of PAWP. This study was therefore designed to evaluate the relation between doppler transmitral flow velocity indexes and measured PAWP in 91 patients (learning group: 73 men, mean age 57 +/- 13 years) with ischemic heart disease (n = 41), dilated (n = 29) or hypertrophic cardiomyopathy (n = 4), or aortic stenosis (n = 17). Multiple regression analysis was used to derive an equation for estimation of PAWP, which was subsequently tested in a separate group of 33 patients (testing group: 28 men, mean age 58 +/- 12 years) with similar cardiac conditions. PAWP ranged from 4 to 48 mm Hg in the learning group and from 7 to 40 mm Hg in the testing group. In the learning group, PAWP correlated with the E/A ratio (r = 0.95), atrial filling fraction (r = -0.80), peak E velocity (r = 0.79), isovolumic relaxation period (r = -0.75), and deceleration time (r = -0.61). In the learning group, PAWP was best predicted as PAWP = 18.4 + [17.1.In(E/A ratio)]. This equation allowed prediction of PAWP within 3 mm Hg of the measured value in 24 of 33 patients (73%) in the testing group. In 8 additional patients, the equation also accurately predicted the changes in PAWP induced by volume loading or intravenous nitrates (r = 0.98).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Velocidade do Fluxo Sanguíneo , Ecocardiografia Doppler , Cardiopatias/fisiopatologia , Pressão Propulsora Pulmonar , Idoso , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/fisiopatologia , Feminino , Cardiopatias/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos
9.
Rev Esp Cardiol ; 47(12): 843-6, 1994 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-7855381

RESUMO

Myotonic dystrophy is an hereditary multisystemic disease, characterized by slowly progressive myotonic atrophy of skeletic muscles. The heart is frequently affected with occurrence of arrhythmias and His-Purkinje system dysfunction and, less frequently, myocardial dysfunction. The surface ECG is the most sensible indicator of heart disease, and the most common electrophysiological finding is the prolongation of the H-V interval. Patients usually have few cardiovascular symptoms, but when present, the most frequent are: syncope, arrhythmias, atrioventricular block, congestive heart failure and sudden death. We present two patients with sustained monomorphic ventricular tachycardia as initial presentation of cardiac disease.


Assuntos
Distrofia Miotônica/complicações , Taquicardia Ventricular/etiologia , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia Ventricular/fisiopatologia
10.
Sci Total Environ ; 139-140: 225-36, 1993 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-8272831

RESUMO

The GICBEM (Groupe Interface Chimie Biologie des Ecosystèmes Marins) program consists of an evaluation of the ecosystem health status in the Mediterranean Sea mainly based on chemical and biochemical approaches. Specific chemical contaminants (polycyclic aromatic hydrocarbons (PAH), polychlorobiphenyls (PCB), heavy metals) in waters, sediments, and related biotransformation indicators in target organisms (mussels, fish) have been selected for a complete survey of the coastal waters. In order to provide an appropriate sampling program for standardization for each sampling cruise, various aspects have been studied: (a) parameters for the choice of the sample sites; (b) ways of collection the samples (waters, sediments, marine organisms); and (c) preparation of the samples for a short term storage on board ship and for further analyses in the ground laboratory. Methods of preparation and storage of the samples are described and could be used to initiate an environmental banking program including both possible retrospective analyses of chemical pollutants and biochemical indicators. Moreover, the correlation between chemicals (PAH) and biochemical (mixed function oxygenase activities) parameters has been studied and this demonstrates the capability of the enzyme activities as reliable pollution biomarkers.


Assuntos
Monitoramento Ambiental , Metais/análise , Bifenilos Policlorados/análise , Compostos Policíclicos/análise , Bancos de Tecidos/organização & administração , Poluentes Químicos da Água/análise , Animais , Bivalves , Ecologia , Peixes , Mar Mediterrâneo , Água do Mar , Manejo de Espécimes
11.
Cathet Cardiovasc Diagn ; 29(3): 203-9, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8402843

RESUMO

The atherosclerotic lesion resistance to balloon inflation was assessed prospectively in 200 patients undergoing primary single-site balloon percutaneous transluminal coronary angioplasty (PTCA) by using an identical inflation protocol. This resistance was evaluated by the stenosis resolution pressure, which is the pressure at which the lesion mark is no longer visible on the inflated balloon. The stenosis resolution pressure distribution was normal with a mean value of 4.4 +/- 2.3 atmospheres. Multivariate analysis revealed 4 factors related to the stenosis resolution pressure: stable angina pectoris (p < 10(-6)), the presence of calcifications (p = 0.016), the occurrence of vessel wall dissection after balloon angioplasty (p = 0.005), and the absence of a branch arising in the middle of the stenosis (p = 0.047). It is concluded that the mechanical resistance of the coronary lesion is related to the anginal status, the presence of calcifications, and the occurrence of vessel wall dissection after balloon angioplasty, probably on the basis of the plaque composition.


Assuntos
Angioplastia Coronária com Balão , Doença da Artéria Coronariana/terapia , Angina Pectoris/epidemiologia , Angina Instável/epidemiologia , Angioplastia Coronária com Balão/efeitos adversos , Calcinose/epidemiologia , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/epidemiologia , Vasos Coronários/lesões , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Pressão , Estudos Prospectivos
13.
Mutat Res ; 301(2): 113-9, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7678168

RESUMO

The ability of the mussel postmitochondrial fraction (S9) to activate benzo[a]pyrene (BaP) and 2-aminoanthracene (2AA) to mutagenic metabolites towards Salmonella typhimurium strain TA98 was tested. The mechanisms involved in this activation were investigated and mussel cytochrome P-450-dependent monooxygenases and its NADPH cytochrome c reductase were found to contribute to the activation of BaP. This activation was improved by treating the mussel with 4,5,4',5'-tetrachlorobiphenyl (TCB) (a 3-methylcholanthrene-type inducer of cytochrome P-450-dependent monooxygenase in marine fish) and was inhibited by alpha-naphthoflavone (ANF), a cytochrome P-450 inhibitor. However, both BaP activation and cytochrome P-450-related metabolic activities are much weaker in mussels than in vertebrates. Mussel S9 activates aromatic amines more effectively than BaP. Pretreatment of mussels with TCB or addition of ANF in the incubation medium has no effect on 2AA activation. As suggested by Kurelec (1985), aromatic amine metabolism may be supported by a flavoprotein mixed-function amine oxidase which is NADPH-dependent.


Assuntos
Antracenos/toxicidade , Benzo(a)pireno/toxicidade , Mutagênicos/toxicidade , Animais , Antracenos/metabolismo , Benzo(a)pireno/metabolismo , Benzoflavonas/metabolismo , Biotransformação , Bivalves/enzimologia , Cádmio/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Indução Enzimática , Extratos Hepáticos/metabolismo , Oxigenases de Função Mista/metabolismo , Testes de Mutagenicidade , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Bifenilos Policlorados/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética
14.
J Am Coll Cardiol ; 20(4): 813-21, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1388182

RESUMO

OBJECTIVE: The aim of the present study was to evaluate the hemodynamic and volume correlates of early diastolic filling and isovolumetric relaxation in patients with aortic stenosis. BACKGROUND: Left ventricular diastolic relaxation and filling have been found to be heterogeneous in patients with aortic stenosis. Potential mechanisms underlying this heterogeneity include individual differences in the severity of muscle hypertrophy or systolic dysfunction, or both, in the presence and severity of mitral regurgitation and in the level of left atrial pressure. METHODS: Right (fluid-filled) and left (high fidelity micromanometer) ventricular pressures, left ventricular volumes (contrast angiography) and transmitral inflow dynamics (Doppler echocardiography) were measured in 17 patients with isolated severe aortic stenosis (valve area less than 0.75 cm2). Measurements included left ventricular end-diastolic and end-systolic volumes, left ventricular ejection fraction, peak positive and negative first derivative of left ventricular pressure (dP/dt), the time constant of isovolumetric relaxation (tau), left ventricular end-diastolic pressure, left ventricular mass, left ventricular end-systolic stress, mean capillary wedge pressure and peak early (E) and late (A) transmitral filling velocities. Patients were subclassified according to left ventricular ejection performance at rest and mean capillary wedge pressure. RESULTS: Patients with normal ejection performance and normal mean capillary wedge pressure had a normal rate of isovolumetric left ventricular pressure decay and an abnormal diastolic filling pattern, with diastolic filling occurring primarily during atrial systole. In contrast, in patients with systolic dysfunction and elevated mean capillary wedge pressure, isovolumetric pressure decay was prolonged and diastolic filling occurred essentially during the rapid filling period, with reduced atrial contribution to left ventricular filling and a short isovolumetric relaxation period. Stepwise multiple linear regression analysis identified two variables as independent predictors of transmitral velocity profile and three variables independently predictive of the rate of left ventricular pressure decay. The single most important predictor of transmitral filling pattern was the pulmonary capillary wedge pressure (p less than 0.0001), followed by the left ventricular peak negative dP/dt (p = 0.002). The single most powerful predictor of the rate of reduction in left ventricular pressure was left ventricular mass index (p less than 0.0001), followed by end-systolic volume index (p = 0.0002) and left ventricular peak negative dP/dt (p = 0.0029). CONCLUSIONS: In patients with aortic stenosis, left ventricular filling is essentially determined by left atrial pressure, whereas isovolumetric relaxation more closely depends on the severity of muscle hypertrophy and chamber dilation.


Assuntos
Estenose da Valva Aórtica/fisiopatologia , Diástole/fisiologia , Hemodinâmica/fisiologia , Função Ventricular Esquerda/fisiologia , Idoso , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/diagnóstico por imagem , Cateterismo Cardíaco , Cardiomegalia/complicações , Ecocardiografia , Feminino , Humanos , Masculino , Insuficiência da Valva Mitral/complicações , Pressão Propulsora Pulmonar/fisiologia , Análise de Regressão , Volume Sistólico/fisiologia
15.
J Am Coll Cardiol ; 18(5): 1251-8, 1991 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-1918702

RESUMO

Asynchronous segmental early relaxation, defined as a localized early segmental outward motion of the left ventricular endocardium during isovolumetric relaxation, has been associated with an altered left ventricular relaxation rate. To determine whether asynchronous segmental early relaxation also results in impaired left ventricular filling, early diastolic ventricular wall motion and Doppler-derived left ventricular filling indexes were examined in 25 patients with documented coronary artery disease and normal systolic function. Patients were further classified into two groups according to the presence (n = 15, group 1) or absence (n = 10, group 2) of asynchronous early relaxation at left ventriculography. A third group of 10 age-matched normal subjects served as a control group. No differences were observed between the two patient groups with coronary artery disease with respect to age, gender distribution, heart rate, left ventricular systolic and diastolic pressures or extent and severity of coronary artery disease. No differences in transmitral filling dynamics were observed between group 2 patients and age-matched control subjects. Conversely, group 1 patients had significantly lower peak early filling velocities (44 +/- 11 vs. 58 +/- 11 cm/s, p less than 0.01), larger atrial filling fraction (45 +/- 4% vs. 38 +/- 4%, p less than 0.001), lower ratio of early to late transmitral filling velocities (0.6 +/- 0.08 vs. 0.99 +/- 0.18, p less than 0.001) and a longer isovolumetric relaxation period (114 +/- 12 vs. 90 +/- 6 ms, p less than 0.001) compared with group 2 patients and control subjects.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Doença das Coronárias/fisiopatologia , Sístole/fisiologia , Idoso , Cateterismo Cardíaco , Doença das Coronárias/diagnóstico por imagem , Diástole/fisiologia , Ecocardiografia Doppler , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Filmes Cinematográficos , Ventriculografia com Radionuclídeos , Valores de Referência , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia
16.
Circulation ; 84(5 Suppl): III268-74, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1934419

RESUMO

Increasing blood flow results in endothelium-dependent vasodilation of angiographically normal epicardial coronary arteries in humans. To compare the ability of internal mammary artery (IMA) and saphenous vein (SV) used as coronary artery bypass grafts to adapt their vasomotor tone to an increase in myocardial blood flow demand induced by tachycardia, 10 IMA and seven SV grafts were studied by quantitative angiography more than 6 months (range, 6-82 months) after surgery in 17 patients. All grafts were angiographically smooth and implanted to large nonakinetic perfusion zones. Angiograms were obtained in basal sinus rhythm (71 +/- 10 beats/min), during atrial pacing (129 +/- 9 beats/min), and after intragraft infusion of 1 mg isosorbide dinitrate (ISDN). In basal sinus rhythm, the cross-sectional area of SV was superior to that of IMA (10.7 +/- 3.6 versus 5.4 +/- 1.7 mm2; p less than 0.01). All IMA dilated during pacing (+14.8 +/- 11.5%; p less than 0.005) and a further increase in IMA cross-sectional area occurred after ISDN (+27.4 +/- 20.1% versus basal; p less than 0.005). In contrast, SV failed to dilate during pacing (+0.3 +/- 5.4%; p = NS) and after ISDN (+0.7 +/- 6.0% versus basal; p = NS). Thus, an increase in myocardial blood flow demand induced by tachycardia results in dilation of IMA but not of SV grafted on coronary vessels. The ability of the endothelium to modulate the vasomotor tone of IMA grafts in response to changes in blood flow could contribute to their excellent long-term functional results after coronary artery bypass surgery.


Assuntos
Ponte de Artéria Coronária , Endotélio Vascular/fisiologia , Anastomose de Artéria Torácica Interna-Coronária , Veia Safena/transplante , Taquicardia/fisiopatologia , Sistema Vasomotor/fisiologia , Adaptação Fisiológica/fisiologia , Estimulação Cardíaca Artificial , Angiografia Coronária , Circulação Coronária/fisiologia , Feminino , Humanos , Dinitrato de Isossorbida , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Fatores de Tempo
17.
J Am Coll Cardiol ; 18(2): 506-11, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1856419

RESUMO

After successful coronary angioplasty, the minimal luminal diameter of the dilated coronary artery segment is generally smaller than the diameter of the largest balloon catheter at the maximal inflation pressure. The determinants of this phenomenon were studied in 28 patients. Biplane angiograms were obtained after intracoronary administration of isosorbide dinitrate (1 mg) before, immediately and 24 h after coronary angioplasty. Balloon and coronary luminal diameters were measured by automated contour detection. Immediately after the procedure, the difference between inflated balloon diameter and minimal luminal diameter averaged 0.93 +/- 0.43 mm for the entire group and was greater both in eccentric stenoses (1.13 +/- 0.39 vs. 0.70 +/- 0.36 mm; p less than 0.01) and after angioplasty with an oversized balloon (1.20 +/- 0.37 vs. 0.71 +/- 0.33 mm; p less than 0.005). At 24 h, the balloon - minimal luminal diameter difference was unchanged at the group level (0.86 +/- 0.38 mm, but the minimal luminal diameter increased significantly in the subgroup of coronary segments dilated with an oversized balloon (1.97 +/- 0.37 vs. 1.81 +/- 0.28 mm; p less than 0.05). Thus, the difference between the minimal diameter of a dilated coronary segment immediately after a successful coronary balloon angioplasty procedure and the maximal diameter of the inflated balloon catheter is dependent both on eccentricity of the stenosis and on the balloon/artery diameter ratio. Moreover, the increase in minimal luminal diameter 24 h after angioplasty performed with an oversized balloon suggest that in addition to elastic recoil partly reversible factors related to vessel barotrauma are involved.


Assuntos
Angioplastia Coronária com Balão/instrumentação , Doença das Coronárias/terapia , Vasos Coronários/fisiopatologia , Músculo Liso Vascular/fisiopatologia , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/fisiopatologia , Constrição Patológica/terapia , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/fisiopatologia , Elasticidade , Feminino , Humanos , Dinitrato de Isossorbida , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
18.
Cathet Cardiovasc Diagn ; 22(3): 167-73, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2013078

RESUMO

Percutaneous transluminal angioplasty (PTCA) of coronary stenoses involving major bifurcations carries a small but significant risk of side branch occlusion which can be avoided by simultaneously using multiple dilatation systems. Among 1,275 PTCA procedures performed between 1984 and 1988 in 1,035 consecutive patients, 42 double wire procedures were applied (4%) to protect and/or dilate major coronary side branches. A total of 80 coronary stenoses were attempted of which 76 were located on a bifurcation and 4 on other segments. In the first 11 patients (group A), 2 guiding catheters were used and PTCA of each vessel was successfully performed by means of separate double lumen over-the-wire balloon catheters. In the next 31 patients (group B), 2 guidewires were advanced through a single guiding catheter and PTCA was attempted using "Monorail" balloon catheters sequentially advanced over the wires. In group B, a successful PTCA was obtained in 29 patients (93%) but twisting of the wires hampered balloon progression in 5 cases, such that dilatation could only be performed by stepping back to a single wire technique. The procedure time in group B was significantly shorter than in group A: 144 +/- 30 versus 230 +/- 52 minutes (p = .01). Repeat angiography was performed in 35 out of 40 patients (87%) after a mean of 180 +/- 46 days following successful PTCA. Angiographic restenosis was present in 37% (24/65) of bifurcation segments which, in our experience, is not significantly different from the angiographic restenosis rate in less complex lesions (248/740; 34%; NS).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Angioplastia Coronária com Balão/métodos , Doença das Coronárias/terapia , Angiografia , Constrição Patológica/epidemiologia , Constrição Patológica/terapia , Angiografia Coronária , Doença das Coronárias/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Fatores de Tempo
19.
Artigo em Inglês | MEDLINE | ID: mdl-1677851

RESUMO

1. The aim of this work was to evaluate the relationships between free radical scavengers and lipid peroxidation in the common mussel Mytilus edulis. 2. Mussels were exposed to compounds known for their ability to produce free radicals (carbon tetrachloride, CCl4) and reactive oxygen species via redox cycling (menadione) and the effects on digestive gland, gills and remaining tissues were studied. 3. Lipid peroxidation parameters and the status of free radical scavengers (glutathione, vitamins A, E and C) were affected more by exposure to menadione than to CCl4. 4. The observed changes in the free radical scavengers content are indicative of a role in detoxication of damaging reactive species.


Assuntos
Bivalves/metabolismo , Sequestradores de Radicais Livres , Peroxidação de Lipídeos/efeitos dos fármacos , Animais , Bivalves/efeitos dos fármacos , Tetracloreto de Carbono/toxicidade , Oxirredução , Vitamina K/toxicidade
20.
Am J Cardiol ; 63(12): 847-52, 1989 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-2929442

RESUMO

To assess the feasibility and efficacy of percutaneous mitral commissurotomy (PMC), the procedure was attempted in 200 patients with severe mitral stenosis. There were 154 women and 46 men, their mean age was 43 +/- 16 years (range 13 to 79) and 15 were older than 70 years of age. Forty-four had had previous surgical commissurotomy. Forty were in New York Heart Association class II, 152 in class III and 8 in class IV. In regard to valvular anatomy, 67 had calcified valves, 58 had pliable valves and only mild subvalvular disease, and 75 had flexible valves but extensive subvalvular disease. Grade 1+ mitral regurgitation was present in 62 and grade 2+ in 2. In 11 patients the procedure was discontinued because of complications in 3 and technical failure in 8. Six of the 8 technical failures occurred during the first 15 attempts. Effective PMC was performed in 189 patients using 1 balloon in 23 and 2 balloons in 166. After PMC, there was a significant improvement in mean left atrial pressure (21 +/- 7 to 12 +/- 5 mm Hg, p less than 0.0001), mean mitral gradient (16 +/- 6 to 6 +/- 2 mm Hg, p less than 0.0001), cardiac index (2.6 +/- 0.8 to 3.1 +/- 0.8 liters/min/m2, p less than 0.001) and valve area assessed by hemodynamics (1.1 +/- 0.3 to 2.2 +/- 0.5 cm2, p less than 0.0001) and 2-dimensional echocardiography (1 +/- 0.3 to 1.9 +/- 0.4 cm2, p less than 0.0001). No patient died. Embolism occurred in 8 (4%), with no further sequelae. Sixteen (8%) had atrial septal defect detected by oxymetry.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Cateterismo , Estenose da Valva Mitral/cirurgia , Valva Mitral , Adulto , Cateterismo/efeitos adversos , Cateterismo/métodos , Ecocardiografia , Feminino , Seguimentos , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Estenose da Valva Mitral/fisiopatologia
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