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2.
BMC Cardiovasc Disord ; 20(1): 504, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33256590

RESUMEN

BACKGROUND: Annually > 10% of patients with atrial fibrillation on oral anticoagulation undergo invasive procedures. Optimal peri-procedural management of anticoagulation, as judged by major bleeding and thromboembolic events, especially in the elderly, is still debated. METHODS: Procedures from 1442 patients were evaluated. Peri-procedural edoxaban management was guided only by the experience of the attending physician. The primary safety outcome was the rate of major bleeding. Secondary outcomes included the peri-procedural administration of edoxaban, other bleeding events, and the main efficacy outcome, a composite of acute coronary syndrome, non-hemorrhagic stroke, transient ischemic attack, systemic embolic events, deep vein thrombosis, pulmonary embolism, and mortality. RESULTS: Of the 1442 patients, 280 (19%) were < 65, 550 (38%) were 65-74, 514 (36%) 75-84, and 98 (7%) were 85 years old or older. With increasing age, comorbidities and risk scores were higher. Any bleeding complications were uncommon across all ages, ranging from 3.9% in patients < 65 to 4.1% in those 85 years or older; major bleeding rates in any age group were ≤ 0.6%. Interruption rates and duration increased with advancing age. Thromboembolic events were more common in the elderly, with all nine events occurring in those > 65, and seven in patients aged > 75 years. CONCLUSION: Despite increased bleeding risk factors in the elderly, bleeding rates were small and similar across all age groups. However, there was a trend toward more thromboembolic complications with advancing age. Further efforts to identify the optimal management to reduce ischemic complications are needed. TRIAL REGISTRATION: NCT# 02950168, October 31, 2016.


Asunto(s)
Fibrilación Atrial/tratamiento farmacológico , Trastornos Cerebrovasculares/prevención & control , Inhibidores del Factor Xa/administración & dosificación , Piridinas/administración & dosificación , Tiazoles/administración & dosificación , Tromboembolia/prevención & control , Administración Oral , Factores de Edad , Anciano , Anciano de 80 o más Años , Asia/epidemiología , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/epidemiología , Trastornos Cerebrovasculares/diagnóstico , Trastornos Cerebrovasculares/epidemiología , Esquema de Medicación , Europa (Continente)/epidemiología , Inhibidores del Factor Xa/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Atención Perioperativa , Hemorragia Posoperatoria/inducido químicamente , Hemorragia Posoperatoria/epidemiología , Estudios Prospectivos , Piridinas/efectos adversos , Sistema de Registros , Medición de Riesgo , Factores de Riesgo , Tiazoles/efectos adversos , Tromboembolia/diagnóstico , Tromboembolia/epidemiología , Resultado del Tratamiento
5.
Eur Phys J E Soft Matter ; 20(1): 29-36, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16733636

RESUMEN

This paper deals with the interaction between zein (the main protein component of corn grain) and water. It induces macroscopic properties changes and may allow for the understanding of the basis of zein endosperm structure: vitreous endosperm is compact and floury endosperm is porous, giving the endosperm its hard and soft textures, respectively. In that aim porous pills made by compaction of zein powder submitted to different hydration/dehydration processes have been prepared and studied. In particular, imbibition measurements of a pure-water drop deposited onto a zein pill were performed. Also, desiccation of a zein pill previously imbibed induces strong mechanical stresses leading to crack formation and/or large deformations.


Asunto(s)
Proteínas de Plantas/química , Tensoactivos/química , Zeína/química , Mecánica , Porosidad , Estrés Mecánico , Propiedades de Superficie , Factores de Tiempo
6.
Heart ; 92(8): 1113-8, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16449513

RESUMEN

OBJECTIVE: To test whether preserved coronary flow reserve (CFR) two days after reperfused acute myocardial infarction (AMI) is associated with less microvascular dysfunction (" no-reflow" phenomenon) and is predictive of myocardial viability. DESIGN: 24 patients with anterior AMI underwent CFR assessment in the left anterior descending coronary artery (LAD) with transthoracic echocardiography and myocardial contrast echocardiography (MCE) 48 h after primary angioplasty in the LAD (mean 4 (SD 2) and 3 (1) days, respectively). Low-dose dobutamine echocardiography was performed 6 (3) days after AMI and follow-up echocardiography at three months. RESULTS: No-reflow extent was greater in patients with impaired CFR (< 2.5) than in those with preserved CFR (> 2.5) (55 (35)% v 11 (25)%, p < 0.001). MCE reflow was more common in patients with preserved CFR (8/12) than in those with reduced CFR (1/12, p < 0.05). Wall motion score index in the LAD territory (A-WMSI) was similar at the first echocardiography (2.14 (0.39) v 2.32 (0.47), NS), although it was better in patients with preserved CFR at dobutamine (1.38 (0.45) v 1.97 (0.67), p < 0.05) and follow-up echocardiography (1.36 (0.40) v 1.97 (0.64), p < 0.05). An inverse correlation was found between CFR and A-WMSI at dobutamine and follow-up echocardiography (r = -0.49, p = 0.016 and r = -0.55, p = 0.005) and between MCE and A-WMSI at dobutamine and follow-up echocardiography (r = -0.75, p < 0.001 and r = -0.75, p < 0.001). By multivariate analysis MCE reflow remained the only predictor of recovery at both dobutamine and follow-up echocardiography (odds ratio 1.06, 95% CI 1 to 1.1, p = 0.009). CONCLUSION: CFR is inversely correlated with the extent of microvascular dysfunction at MCE two days after reperfused AMI. CFR and MCE reflow early after AMI are correlated with myocardial viability at follow up.


Asunto(s)
Angioplastia Coronaria con Balón , Circulación Coronaria/fisiología , Infarto del Miocardio/fisiopatología , Velocidad del Flujo Sanguíneo/fisiología , Ecocardiografía Doppler en Color , Ecocardiografía de Estrés , Femenino , Humanos , Masculino , Microcirculación , Persona de Mediana Edad , Infarto del Miocardio/terapia , Miocardio
7.
Biomacromolecules ; 5(5): 1792-8, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15360289

RESUMEN

Debranching and crystallization occurring during the enzymatic treatment of 25% (w/v) aqueous solutions of maltodextrins by isoamylase at 52 degrees C were studied. The morphology as well as the crystal and molecular structures of the precipitates formed at different stages of the reaction were characterized. Two types of resulting products, differing in terms of structure and morphology, were evidenced. A loose B-type network, containing linear and branched chains of highest molecular weight, was mainly formed during the first 12 h of reaction, whereas aggregates of A-type lamellar crystals, made of short linear chains, were predominantly obtained between 12 and 48 h. The aggregation behavior as a function of temperature and molecular weight distribution of such substrates was discussed and compared to that of related starch products.


Asunto(s)
Isoamilasa/metabolismo , Polisacáridos/análisis , Polisacáridos/metabolismo , Cristalización
8.
Ann Rheum Dis ; 62(9): 890-3, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12922965

RESUMEN

OBJECTIVE: To investigate whether coronary flow reserve (CFR), measured by a new non-invasive method, is impaired early in patients with systemic sclerosis (SSc) and whether CFR impairment correlates with clinical or functional measures, or both. METHODS: 27 patients with SSc without clinical evidence of ischaemic heart disease and 23 control group subjects matched for age and sex were studied. CFR was evaluated in the left anterior descending coronary artery (LAD) with a new non-invasive method: contrast (Levovist) enhanced transthoracic Doppler during adenosine infusion. The pulsed wave Doppler examination of blood flow velocity was recorded in the LAD at rest and after maximum vasodilatation by adenosine infusion. RESULTS: In patients with SSc, without clinical evidence of ischaemic heart disease, CFR was impaired (p=0.0001). 14/27 patients with SSc had severe reduction of the CFR (< or =2.5) compared with controls (p=0.002). A non-significant trend between mean CFR and the severity and duration of the disease was also seen. CONCLUSIONS: CFR is often reduced in patients with SSc, suggesting early preclinical cardiac involvement in SSc. This impairment in coronary microvasculature is detectable by a non-invasive echocardiographic method and in this study was more common in the diffuse form of SSc.


Asunto(s)
Circulación Coronaria , Esclerodermia Sistémica/fisiopatología , Adulto , Anciano , Velocidad del Flujo Sanguíneo , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/fisiopatología , Ecocardiografía Doppler/métodos , Femenino , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Esclerodermia Sistémica/diagnóstico por imagen
9.
Bone Marrow Transplant ; 29(10): 833-42, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12058233

RESUMEN

This retrospective study compares high-dose therapy (HDT) with autologous stem cell transplantation and combined-modality treatment (CT) as a first-line therapy for Hodgkin's disease (HD) for patients with both a clinical stage (CS) IV and/or a mediastinal mass > or =0.45 of the thoracic diameter (MM > or =0.45) at diagnosis, and an incomplete response after the first-line chemotherapy. Data on 42 grafted patients (GP) in Nantes Hospital, France and on 108 combined-modality treated patients (CTP) from two protocols of the GOELAMS group, France (POF 81 and H90) was analyzed. Both groups were comparable except for pulmonary disease in excess in the grafted group (P = 0.01). Among GP, 95% were in complete response at the end of first-line treatment and 77% among CTP. Median follow-up was 53 months (range, 7 to 128 months) for GP and 88 months (range, 25 to 181 months) for CTP. The 5-year freedom from progression (FFP) and event-free survival (EFS) rates were better for GP (87% vs 55% for FFP: P = 0.0004 and 81% vs 51% for EFS: P = 0.0004) whereas the overall survival (OS) rates did not differ significantly (85% for GP vs 71% for CTP: P = 0.06). Similar results were obtained for the groups with a response > or =50% after initial chemotherapy: 91% vs 65% for FFP, P = 0.01; 87% vs 61% for EFS, P = 0.02; and 92% vs 77% for OS, P = 0.2; and for the groups with a response <50%: 80% vs 22% for FFP, P = 0.0003; 72% vs 13% for EFS, P = 0.0001; and 76% vs 46% for OS, P = 0.04. This study shows a better control of the disease with HDT.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Enfermedad de Hodgkin/terapia , Adolescente , Adulto , Anciano , Niño , Preescolar , Protocolos Clínicos , Terapia Combinada , Supervivencia sin Enfermedad , Femenino , Enfermedad de Hodgkin/tratamiento farmacológico , Enfermedad de Hodgkin/patología , Enfermedad de Hodgkin/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Retrospectivos , Factores de Riesgo , Trasplante Autólogo , Irradiación Corporal Total
10.
J Chromatogr A ; 917(1-2): 179-85, 2001 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-11403469

RESUMEN

The coupling between flow field-flow fractionation (FFF), multi-angle laser light scattering and differential refractometer index provides a promising technique for fractionation of starch polysaccharides in aqueous conditions. Native starches with different amylose/amylopectin levels (0-70%) as well as a pure amylose sample were characterized. By applying a sudden drop in the cross-flow-rate, clear separation was achieved between amylose (which elutes first) and amylopectin. Flow FFF produced correct relationships between the molecular mass or the gyration radius versus elution volume for the fractionated amylopectin population. The results are also considered in terms of the macromolecular composition of starches.


Asunto(s)
Amilopectina/química , Polisacáridos/análisis , Fraccionamiento Químico , Rayos Láser , Luz , Refractometría , Dispersión de Radiación
11.
J Agric Food Chem ; 49(2): 675-82, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11262011

RESUMEN

The baking expansion properties of sour cassava starch (Polvilho azedo) are attributable to photochemical starch degradation induced by heterolactic fermentation after sun-drying. This study investigated the effects of UV irradiation on the different structural levels of cassava starch as compared to those of corn starch and dextrins. Photosensitive compounds excited at 360 and 290 nm in cassava starch were photodegraded when starch was exposed to sunlight or 360 nm irradiation. UV irradiation depolymerized cassava and corn starches, inducing modifications due, at least in part, to a mechanism involving free radicals. Lactic acid was also photodegraded. Photodegradation induced by UV absorption could have been due to fluorescent chromophores found in starches and nonfluorescent chromophores present in glucosidic units.


Asunto(s)
Manihot , Almidón/química , Zea mays , Culinaria , Dextrinas/química , Dextrinas/efectos de la radiación , Fermentación , Manipulación de Alimentos , Manihot/efectos de la radiación , Fotólisis , Almidón/efectos de la radiación , Luz Solar , Rayos Ultravioleta , Zea mays/efectos de la radiación
12.
Am Heart J ; 141(2 Suppl): S36-44, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11174357

RESUMEN

BACKGROUND: Contrast media, used in conjunction with newly developed echocardiographic techniques, can currently be used in several clinical settings: (1) the study of myocardial perfusion, (2) delineation of the endocardial border in technically difficult echocardiographic examinations, and (3) enhancement of low-intensity blood flow, especially coronary blood flow, to study coronary flow reserve. METHODS: Published studies were reviewed to identify the advantages of associating contrast perfusion with classic or new echocardiographic and ultrasonographic imaging techniques in the study of myocardial perfusion and coronary artery flow. RESULTS: Several studies demonstrated the usefulness of contrast echocardiography, even in patients with a bad acoustic window, in evaluating opacification of the left ventricle or in enhancing echocardiographic color Doppler studies of coronary flow and coronary flow reserve. Preliminary results of transthoracic echocardiographic studies of myocardial perfusion are described. CONCLUSIONS: The clinical applications of contrast echocardiography are effective in exploiting examinations that provide poor diagnostic information (ventricular cavity opacification) or in obtaining new physiopathologic data (microvascular opacification/perfusion and coronary flow reserve). The evaluation of coronary flow reserve by contrast-enhanced transthoracic Doppler ultrasonography is an attractive new diagnostic modality that points the way toward important new clinical applications of contrast echocardiography. This technique is useful in evaluating the severity of coronary artery disease of the left anterior descending coronary artery and in all clinical conditions in which the effects of therapeutic interventions aimed at improving coronary flow reserve need to be monitored.


Asunto(s)
Medios de Contraste , Enfermedad Coronaria/diagnóstico por imagen , Ecocardiografía Doppler en Color/métodos , Velocidad del Flujo Sanguíneo , Medios de Contraste/administración & dosificación , Medios de Contraste/normas , Circulación Coronaria , Enfermedad Coronaria/fisiopatología , Ecocardiografía Doppler en Color/normas , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/fisiopatología , Humanos , Contracción Miocárdica , Índice de Severidad de la Enfermedad , Función Ventricular Izquierda
14.
Eur J Echocardiogr ; 2(4): 253-61, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11888819

RESUMEN

AIMS: Patients with poor quality echocardiograms impede the application of available automatic boundary detection technologies. Tissue harmonic imaging and contrast media can allow optimal differentiation of left ventricular blood pool and tissue, making it possible to utilize automatic boundary detection software for automatic non-operator-dependent computation of left ventricular volumes. We integrated contrast-enhanced harmonic colour Doppler with a semiautomated boundary detection algorithm to explore the feasibility, accuracy and inter-observer variability for left ventricular volume assessment in technically difficult patients. METHODS AND RESULTS: Twenty-six patients with more than two segments not clearly visualized in tissue harmonic imaging were studied with contrast-enhanced harmonic colour Doppler using Levovist. Twenty patients (77%) achieved full left ventricular contrast filling without apparent blooming artefacts. Contrast-enhanced harmonic colour Doppler-automatic boundary detection was successfully implemented in these 20 patients, despite three (15%) in which it was not possible to acquire more than three cardiac cycles' values. Contrast-enhanced harmonic colour Doppler-automatic boundary detection measurements agreed closely with the manually drawn data. Among the three independent readers in the three techniques, the best correlation, lowest SEE, smallest limits of agreement and inter-observer variability were obtained in contrast-enhanced harmonic colour Doppler-automatic boundary detection. CONCLUSION: Contrast-enhanced harmonic colour Doppler-automatic boundary detection was feasible and accurate in estimation of left ventricular volume and function in patients with poor acoustic windows. This technique significantly reduced inter-observer variability, thus improving reliability and confidence of investigators in left ventricular function assessment. Contrast-enhanced harmonic colour Doppler-automatic boundary detection may have great potential in clinical evaluation of left ventricular volume and function, especially when on-line software is available.


Asunto(s)
Volumen Cardíaco/fisiología , Ecocardiografía Doppler en Color/métodos , Función Ventricular Izquierda/fisiología , Algoritmos , Medios de Contraste , Estudios de Factibilidad , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Aumento de la Imagen , Modelos Lineales , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Estudios Prospectivos
15.
Echocardiography ; 18(8): 639-49, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11801205

RESUMEN

OBJECTIVES: This study compared the efficacy of contrast-enhanced harmonic color Doppler (C-HCD) and tissue harmonic imaging (THI) for left ventricular endocardial border delineation and explored the optimal methodology of C-HCD in patients with suboptimal echocardiograms. BACKGROUND: The value of C-HCD in improving endocardium remains unknown. Effects of harmonic velocity-encoded color Doppler (HVD) and harmonic power Doppler (HPD) as well as contrast administration and image acquisition modalities on left ventricular opacification (LVO) have not been established. METHODS: One hundred (50 HVD, 50 HPD) patients with suboptimal echocardiograms during conventional fundamental echocardiography were studied with THI and C-HCD using Levovist. Each patient underwent different random contrast administration and image acquisition modalities. Endocardial border definition score index (EBDI), blooming artifacts, contrast destruction, and salvage of suboptimal echocardiograms were calculated in each patient after contrast enhancement. RESULTS: EBDI improved from 2.05 +/- 0.61 in THI to 2.73 +/- 0.48 in HVD, and 1.98 +/- 0.73 in THI to 2.69 +/- 0.51 in HPD (both P < 0.001). The conversion of a nondiagnostic image from fundamental echocardiography to an optimal diagnostic image was 33 (33%) patients in THI compared to 77 (77%) patients in C-HCD (P < 0.001). Blooming artifacts were seen more commonly in HVD than HPD, intermittent than continuous image acquisition, and bolus than infusion administration (all P < 0.001). There was less contrast destruction in intermittent compared with continuous image acquisition (P < 0.001). Contrast destruction was similar in HVD and HPD, bolus and infusion injection of contrast. The highest salvage rate of a nondiagnostic image from THI to an optimal diagnostic image was 45.5% and 42.4% in HPD mode, with intermittent image acquisition during bolus and infusion contrast administrations. CONCLUSIONS: C-HCD seems more effective in demonstrating improved endocardial border definition compared to THI. HPD has less blooming artifacts compared with HCD. The optimal method for LVO was to use HPD with intermittent image acquisition during bolus or infusion administration of Levovist.


Asunto(s)
Ecocardiografía Doppler en Color , Ecocardiografía , Obstrucción del Flujo Ventricular Externo/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Artefactos , Medios de Contraste/administración & dosificación , Endocardio/diagnóstico por imagen , Endocardio/efectos de los fármacos , Diseño de Equipo , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/efectos de los fármacos , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Prevalencia , Volumen Sistólico/efectos de los fármacos , Volumen Sistólico/fisiología
16.
Eur J Endocrinol ; 143(3): 363-9, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11022178

RESUMEN

OBJECTIVE: To verify whether the accuracy of data on myocardial function provided by pulsed-wave tissue Doppler imaging (PWTDI), a new echocardiographic application that allows quantitative measurements of myocardial wall velocities, could help towards a better understanding of the natural history of acromegalic cardiomyopathy. DESIGN: Eighteen patients with active acromegaly (ten men and eight women; mean age 48.0+/-15.0 years) with no other detectable cause of heart disease underwent PWTDI. Thirteen healthy individuals matched for age and body mass index acted as a control group. METHODS: Ejection fraction (EF), transmitral early/late diastolic velocity (E/A) ratio and isovolumic relaxation time (IVRT) were measured by conventional echocardiography; systolic peak (Sv) and early (Ev) and late (Av) diastolic peak velocities, Ev/Av ratio and regional IVRT (IVRTs) were obtained by PWTDI. RESULTS: All patients showed appreciably abnormal left ventricular global diastolic function represented by prolongation of the IVRT (P<0.001). Using PWTDI we found a prolongation of IVRTs and inversion of the Ev/Av ratio. In addition, the Ev/Av ratio proved to be significantly negatively correlated with IVRT; this correlation was not present in the case of the E/A ratio. Furthermore, a decrease in Sv was detected in the basal segment of the lateral wall (P<0.01), which had the greatest degree of diastolic dysfunction. CONCLUSIONS: PWTDI confirmed the acknowledged diastolic dysfunction that accompanies acromegalic cardiomyopathy and highlighted the greater sensitivity of regional PWTDI with respect to global Doppler diastolic indexes. Furthermore, by revealing an impairment of regional systolic function in presence of a normal EF, the findings with PWTDI contradicted the largely accepted theory that systolic function remains normal for several years in patients affected by acromegalic cardiomyopathy.


Asunto(s)
Acromegalia/diagnóstico por imagen , Corazón/fisiopatología , Acromegalia/fisiopatología , Adulto , Anciano , Ecocardiografía Doppler de Pulso , Femenino , Humanos , Masculino , Persona de Mediana Edad , Contracción Miocárdica , Reproducibilidad de los Resultados , Función Ventricular Izquierda
17.
Carbohydr Res ; 326(2): 130-44, 2000 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-10877096

RESUMEN

Amylopectin from two double maize mutant starches of A-crystalline (wxdu) and B-crystalline type (aewx) was subjected successively to hydrolysis involving alpha and beta amylases, which isolated clusters and all branching zones of clusters (BZC). Enzymatic analysis together with ionic and size-exclusion chromatography revealed the structural features of the clusters and BZC and their role in starch crystallization. A-type clusters were larger (dp(n) > 80) and contained more (but shorter) chains than B-type clusters. The BZC of A-type starch was also larger, but with a shorter distance between the branching points than in B-type BZC. A-type clusters had a densely packed structure and B-type a poorly branched structure. Models for the structure of A- and B-type clusters are presented, and a hypothesis for the influence of cluster geometry on crystallization is proposed.


Asunto(s)
Amilopectina/química , Mutación , Almidón/química , Zea mays/química , Zea mays/genética , Amilopectina/genética , Conformación de Carbohidratos , Cromatografía en Agarosa , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Dextrinas/química , Hidrólisis , Almidón/genética , alfa-Amilasas/metabolismo , beta-Amilasa/metabolismo
18.
Ital Heart J ; 1(3): 174-83, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10806984

RESUMEN

Myocardial contraction behaves heterogeneously, being greater in subendocardial than in subepicardial layers. Similarly, during acute myocardial ischemia or infarction, the subendocardium is the first myocardial layer to suffer. Conventional two-dimensional echocardiography cannot distinguish the transmural extension of myocardial ischemia or infarction, showing akinesia also when only the subendocardium is affected. Novel ultrasonographic techniques (like tissue characterization with integrated backscatter or Doppler tissue imaging) and nuclear magnetic resonance tagging can investigate myocardial contraction in different transmural layers and distinguish subendocardial from transmural ischemia or infarction. With the advent of thrombolysis and primary angioplasty in the acute phase of myocardial infarction a correct diagnosis of the extension of myocardial necrosis cannot ignore its transmural wavefront development. The salvage of the subepicardial layer does not give direct information on overall myocardial thickening but is one of the major determinants of overall left ventricular dysfunction and size. Although it is still necessary to investigate this phenomenon, new ultrasonographic techniques give us important information and more opportunities to appropriate diagnosis and future treatment of cardiac patients.


Asunto(s)
Ecocardiografía/métodos , Contracción Miocárdica , Isquemia Miocárdica/diagnóstico por imagen , Miocardio/patología , Animales , Ecocardiografía Doppler/métodos , Cardiopatías/diagnóstico por imagen , Humanos , Microesferas , Contracción Miocárdica/fisiología , Necrosis
19.
J Agric Food Chem ; 48(4): 1322-6, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10775392

RESUMEN

The structure of short dough and biscuit has been characterized at a macroscopic level (dimensions, bulk structure) and a microscopic level (starch damage, protein aggregates, microstructure) by physical and biochemical methods. The baking process of short dough induces a large decrease of the product bulk density from 1.26 to 0. 42 (+/-0.01) g.cm(-)(3) for final biscuit, leading to a cellular solid with a thin colored surface and a porous inner structure. Proteins appear aggregated in biscuit when compared to short dough, whereas starch granules remain almost intact in biscuits. The components which are involved in the cohesiveness of short dough and biscuit final structure have been identified. They suggest that short dough is a suspension of solid particles in a liquid phase being an emulsion of lipids in a concentrated sugar solution. The role of sugars in biscuit structure suggest that biscuit structure is a composite matrix of protein aggregates, lipids and sugars, embedding starch granules.


Asunto(s)
Pan/análisis , Carbohidratos/análisis , Análisis de los Alimentos , Glútenes/análisis , Lípidos/análisis
20.
Am Heart J ; 139(2 Pt 3): S124-30, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10650326

RESUMEN

Left ventricular dilatation after acute myocardial infarction (MI) is a powerful predictor of progressive functional deterioration, culminating in heart failure and death. The most important determinants of post-MI left ventricular remodeling are the size of the infarct, the degree of residual stenosis in the infarct-related artery, and the viability of the infarct zone. In addition to reperfusion therapy and angiotensin-converting enzyme inhibition, metabolic intervention with L-carnitine may represent a therapeutic approach for preventing left ventricular dilatation and preserving cardiac function. Ongoing studies with early metabolic intervention with carnitine in the acute phase of infarction may prove successful in protecting the microcirculation against ischemic damage and enhancing its ability to respond to blood flow resumption. The results of the multicenter, randomized, double-blind Carnitine Ecocardiografia Digitalizzata Infarto Miocardico (CEDIM) trial suggest that the early and long-term administration of L-carnitine attenuates progressive left ventricular dilatation after acute anterior MI. Results show significant, consistent reductions in end-diastolic volume and end-systolic volume in patients who received L-carnitine compared with placebo. The ongoing CEDIM-2 trial (projected 4000 patients with acute MI) will assess the efficacy of L-carnitine in reducing the combined incidence of death and heart failure at 6 months. In addition to standard reperfusion therapy and angiotensin-converting enzyme inhibition, metabolic intervention with L-carnitine may be a therapeutic approach for preventing left ventricular dilatation and preserving cardiac function by limiting infarct size, decreasing residual stenosis in the infarct-related artery, and increasing viability of the infarct zone.


Asunto(s)
Cardiomiopatía Dilatada/etiología , Infarto del Miocardio/complicaciones , Ensayos Clínicos Controlados Aleatorios como Asunto , Remodelación Ventricular , Cardiomiopatía Dilatada/tratamiento farmacológico , Cardiomiopatía Dilatada/fisiopatología , Carnitina/metabolismo , Carnitina/uso terapéutico , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/prevención & control , Humanos , Contracción Miocárdica , Infarto del Miocardio/metabolismo , Infarto del Miocardio/fisiopatología , Miocardio/metabolismo , Tasa de Supervivencia , Resultado del Tratamiento
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