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1.
Clin Exp Dermatol ; 43(8): 917-920, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29862541

RESUMEN

Pemphigus vegetans (PVeg) is a rare variant of pemphigus, characterized by vegetating lesions mainly with antidesmoglein 3 antibodies. However, the pathomechanisms for PVeg is still unknown. We present a patient with PVeg mainly associated with antidesmocollin (Dsc)3 antibodies, who originally developed pemphigus foliaceus. Serum levels of eosinophil cationic protein and transforming growth factor (TGF)-α increased at the onset of PVeg in this patient. Thus, TGF-α might be involved in the formation of vegetating lesions in PVeg.


Asunto(s)
Autoanticuerpos/sangre , Desmogleína 3/inmunología , Proteína Catiónica del Eosinófilo/sangre , Pénfigo/sangre , Factor de Crecimiento Transformador alfa/sangre , Humanos , Masculino , Persona de Mediana Edad , Pénfigo/patología , Piel/patología
2.
Chaos ; 28(5): 055917, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29857690

RESUMEN

We consider a discrete-time version of the continuous-time fashion cycle model introduced in Matsuyama, 1992. Its dynamics are defined by a 2D discontinuous piecewise linear map depending on three parameters. In the parameter space of the map periodicity, regions associated with attracting cycles of different periods are organized in the period adding and period incrementing bifurcation structures. The boundaries of all the periodicity regions related to border collision bifurcations are obtained analytically in explicit form. We show the existence of several partially overlapping period incrementing structures, that is, a novelty for the considered class of maps. Moreover, we show that if the time-delay in the discrete time formulation of the model shrinks to zero, the number of period incrementing structures tends to infinity and the dynamics of the discrete time fashion cycle model converges to those of continuous-time fashion cycle model.

3.
Pharmazie ; 67(8): 740-1, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22957442

RESUMEN

Generation of total intracellular reactive oxygen species (ROS) was measured in XS52 cells, a Langerhans cell-like line, treated with different sized amorphous silica particles. The results suggested that exposure to amorphous nanosilica particles (nSPs) with a particle size of 70 nm induced a higher level of ROS generation than did exposure to micron-sized amorphous silica particles. This finding means that it is essential to examine the biological effects of ROS generated after exposure to nSPs, which will provide useful information for hazard identification as well as the design of safer nanomaterials.


Asunto(s)
Células de Langerhans/metabolismo , Nanopartículas/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Dióxido de Silicio/toxicidad , Línea Celular , Humanos , Células de Langerhans/efectos de los fármacos , Tamaño de la Partícula
4.
Pharmazie ; 65(3): 199-201, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20383940

RESUMEN

Amorphous silica nanoparticles (nSPs), are widely used in medicines, cosmetics and food. However, due to their reduced particle size they are suspected to pose new risks induced by changes in biological reactivity and kinetics, which differ from those of bulk materials. In a previous study, we showed that silica particles with a diameter of 70 nm penetrated the stratum corneum (SC) of mouse skin and were taken up by living cells such as keratinocytes and Langerhans cells. To clarify the relationship between particle size, distribution and cellular response, we have evaluated size-dependent intracellular localization and cytotoxicity of silica particles, using the mouse epidermal Langerhans cell line XS52. On treatment with silica particles of diameters 70, 300, and 1000 nm, cellular uptake and cytotoxicity increased with reduction in particle size. These results suggest that smaller sized silica particles induced greater cytotoxicity against Langerhans cells, which was correlated with the quantity of particle uptake into the cells.


Asunto(s)
Células de Langerhans/efectos de los fármacos , Nanopartículas/toxicidad , Dióxido de Silicio/toxicidad , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Queratinocitos/efectos de los fármacos , L-Lactato Deshidrogenasa/metabolismo , Células de Langerhans/enzimología , Células de Langerhans/ultraestructura , Ratones , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , Timidina/metabolismo
5.
Caries Res ; 42(1): 37-45, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18042990

RESUMEN

The aim of this study was to investigate the influence of salivary macromolecules on enamel lesion remineralization in the presence or absence of fluoride. Paraffin-stimulated whole saliva was centrifuged, and the supernatant was dialyzed in 1,000 molecular-weight cutoff dialysis tubes, first against a phosphate buffer and then against a mineral solution containing Ca and phosphate. Artificial subsurface lesions of human enamel, created in pH 4.5 acetate buffer, were remineralized for 28 days in 4 remineralizing solutions: group C--mineral solution as a control; group S--mineral solution + dialyzed saliva; group F--mineral solution + 1 ppm F; group SF--mineral solution + dialyzed saliva + 1 ppm F. Changes in relative mineral concentration in the lesions were assessed by transverse microradiography. The results showed statistically significant mineral gains in the lesion body in groups C (DeltaZ = 3,254 +/- 1,562% x microm) and SF (DeltaZ = 2,973 +/- 1,349% x microm), but not in groups S (DeltaZ = 5,192 +/- 1,863% x microm) and F (DeltaZ = 4,310 +/- 1,138% x microm) compared with the baseline group (DeltaZ = 5,414 +/- 461% x microm). It was also found that the mineral density at the surface layer in group F (75.0 +/- 15.7%) was greater than that in the baseline group (30.1 +/- 12.3%) with statistical significance, but not in group SF (39.9 +/- 16.5%). It was concluded that the macromolecules inhibited lesion remineralization fundamentally but that these molecules, in the presence of fluoride, seemed to play an important role in the continuation of remineralization by reducing mineral gains at the surface layer.


Asunto(s)
Cariostáticos/metabolismo , Esmalte Dental/metabolismo , Fluoruros/metabolismo , Proteínas y Péptidos Salivales/fisiología , Remineralización Dental , Adulto , Calcio/metabolismo , Cariostáticos/farmacología , Esmalte Dental/efectos de los fármacos , Femenino , Fluorescencia , Fluoruros/farmacología , Humanos , Concentración de Iones de Hidrógeno , Masculino , Microrradiografía , Persona de Mediana Edad , Fosfatos/metabolismo , Desmineralización Dental/metabolismo
6.
J Clin Invest ; 83(1): 46-51, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2521343

RESUMEN

To examine whether atrial natriuretic polypeptide (ANP) is released from the left ventricle in patients with dilated cardiomyopathy (DCM) we measured plasma ANP level in the aortic root (Ao), the anterior interventricular vein (AIV), the great cardiac vein (GCV), and the coronary sinus (CS) in 11 patients with DCM and 18 control subjects. Plasma ANP levels in Ao, AIV, GCV, and CS were 454 +/- 360, 915 +/- 584, 1,308 +/- 926, and 1,884 +/- 1,194 pg/ml, respectively, in the patients with DCM and 108 +/- 42, 127 +/- 55, 461 +/- 224, and 682 +/- 341 pg/ml, respectively, in the control subjects. There was no significant difference in the plasma ANP levels between Ao and AIV in the control subjects. On the contrary, there was a significant (P less than 0.001) step-up in plasma ANP levels between Ao and AIV in patients with DCM. Thus, the difference in ANP levels between Ao and AIV was significantly increased in patients with DCM as compared with the control subjects (461 +/- 248 vs. 19 +/- 59 pg/ml, P less than 0.001). The difference in ANP levels between Ao and CS was also significantly increased in patients with DCM as compared with the control subjects (1,429 +/- 890 vs. 577 +/- 318 pg/ml, P less than 0.001). We conclude that ANP is released in increased amounts into the circulation from the left ventricle as well as from the heart as a whole in patients with DCM.


Asunto(s)
Factor Natriurético Atrial/metabolismo , Cardiomiopatía Dilatada/metabolismo , Miocardio/metabolismo , Anciano , Cateterismo Cardíaco , Femenino , Ventrículos Cardíacos/metabolismo , Humanos , Masculino , Persona de Mediana Edad
8.
Neuroscience ; 140(1): 203-18, 2006 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-16530974

RESUMEN

This study was designed to characterize the morphology of commissural axons, with the goal of revealing some of the organizing principles of their projections in the lumbosacral cord. Axons were labeled anterogradely with biotinylated-dextran amine which was injected in the left lamina VIII and the adjoining parts of lamina VII in the lumbar segments L5-L6 in seven cats. After 3-4 weeks, commissural axons were well labeled throughout lumbosacral segments L1-S2. After crossing the midline at the injection level, labeled axons traveled rostrally and/or caudally in the contralateral ventral and lateral funiculi giving off multiple axon collaterals. The trajectories of 34 single axons were traced in their entirety from their points of origin to their distal ends. Most of these axons were thin (proximal diameter <3.5 microm) and short (<30 mm), and gave off 6 to 32 axon collaterals at short intercollateral distances (mean <2 mm) in the lumbosacral enlargement. Some thicker axons (diameter >3.5 microm) ascended as far as the thoracic level; these supplied only four to six collaterals at long intercollateral intervals ( approximately 6.5 mm). All of the axons except one projected unilaterally. The axons as a whole terminated throughout the contralateral ventral horn. However, axons that traveled in different parts of the white matter had different characteristic terminal arborizations. The collaterals of axons that traveled in the ventral funiculus terminated preferentially in laminae VII-VIII, while those in the lateral funiculus terminated in lamina IX. Although the collateral branching patterns differed from one axon to another, collaterals arising from a particular axon usually exhibited similar patterns at different rostrocaudal levels. These uniform collateral termination patterns indicate that the morphology of each neuron might be specifically related to its function. This may allow future studies to identify different functional types of commissural neurons on the basis of much less extensive reconstructions.


Asunto(s)
Vías Nerviosas/anatomía & histología , Neuronas/fisiología , Médula Espinal/citología , Animales , Axones/metabolismo , Biotina/análogos & derivados , Biotina/metabolismo , Mapeo Encefálico , Gatos , Dextranos/metabolismo , Femenino , Lateralidad Funcional , Región Lumbosacra , Masculino , Vías Nerviosas/metabolismo , Médula Espinal/metabolismo
9.
Cancer Res ; 48(8): 2273-9, 1988 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-2450650

RESUMEN

Monoclonal antibodies (MoAbs) against human osteosarcoma cells were obtained by the fusion of NS/1 mouse myeloma cells with spleen cells from the human osteosarcoma cell line-immunized BALB/c mice. Two hybrid clones were established and designated as 2H10 and 2D3. Both MoAbs reacted strongly with all osteosarcoma tissues but not with other bone and soft tissue tumors such as chondrosarcoma, malignant fibrous histiocytoma, liposarcoma, leiomyosarcoma, and rhabdomyosarcoma. In addition, neither MoAb reacted with tumor cell lines and tissues obtained from other cancers. Immunohistochemical analysis demonstrated that 2H10 and 2D3 reacted with endothelial cells in sarcoma tissues, but not with those of other tumors and normal tissues. 2H10 also reacted with cells on the basal layer of epidermis of the skin. 2H10- and 2D3-defined antigen has an approximate molecular weight of 75,000 under nonreducing and reducing conditions, indicating that the antigen has a single chain structure and there is no intramolecular disulfide bond. 2H10- and 2D3-defined antigen has a pI value between 5.5 and 6.2. Sequential immunoprecipitation analysis clearly demonstrated that 2H10 and 2D3 recognized the same antigen molecule. However, further analysis suggested the possibility that 2H10 and 2D3 MoAbs recognized the different antigenic determinants on the same antigen molecule.


Asunto(s)
Anticuerpos Monoclonales , Antígenos de Neoplasias/análisis , Epítopos/análisis , Osteosarcoma/inmunología , Animales , Antígenos de Neoplasias/inmunología , Humanos , Ratones , Ratones Endogámicos BALB C , Peso Molecular , Células Tumorales Cultivadas
10.
Cancer Res ; 57(6): 1043-6, 1997 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-9067267

RESUMEN

Neovascularization promotes tumor growth by facilitating nutrient exchange and by the paracrine effect. To investigate the relationship between tumor angiogenesis and patient outcome in colorectal cancer, 133 primary tumors were immunostained for CD34 antigen. Blood vessels within five microscopic fields at x200 were counted, and the mean was assigned. Mean patient age was 62.9 years, mean follow-up was 56.4 months, and mean vessel count was 112 (range, 23-298). Cox proportional hazards model and multivariate logistic regression analyses showed that the vessel count was the most important prognostic factor and correlated significantly with hematogenous, but not peritoneal or lymph node, metastasis.


Asunto(s)
Adenocarcinoma/patología , Neoplasias Colorrectales/patología , Metástasis de la Neoplasia/fisiopatología , Neovascularización Patológica/fisiopatología , Adenocarcinoma/irrigación sanguínea , Adenocarcinoma/mortalidad , Adenocarcinoma/secundario , Anciano , Neoplasias Colorrectales/irrigación sanguínea , Neoplasias Colorrectales/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Modelos Logísticos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias Peritoneales/secundario , Pronóstico , Modelos de Riesgos Proporcionales , Resultado del Tratamiento
11.
Cancer Res ; 57(11): 2200-2, 1997 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-9187121

RESUMEN

We investigated the efficacy of hyperthermia and gamma-linolenic acid on experimental carcinoma. This study focused on polyunsaturated fatty acids that are substrates for free radical reactions. Oleic acid, linolenic acid, alpha-linolenic acid, or gamma-linolenic acid was injected into the arteries feeding AH109A carcinoma implanted into rat hind limbs. Among these, gamma-linolenic acid had the greatest effect on tumor tissue lipid peroxidation and demonstrated an antitumor effect. Consequently, gamma-linolenic acid injection into the feeding artery of a tumor was performed immediately prior to hyperthermia. This combination therapy induced a high level of lipid peroxidation in tumor tissue and a significant antitumor effect. Hyperthermia combined with gamma-linolenic acid produces free radical reactions by increasing the radical reaction substrate and may be an effective anticancer modality.


Asunto(s)
Carcinoma/terapia , Ácidos Grasos Insaturados/farmacología , Hipertermia Inducida , Animales , Carcinoma/metabolismo , Peroxidación de Lípido , Masculino , Trasplante de Neoplasias , Ácido Oléico/administración & dosificación , Ácido Oléico/farmacología , Ratas , Vitamina E/farmacología , Ácido alfa-Linolénico/administración & dosificación , Ácido alfa-Linolénico/farmacología , Ácido gammalinolénico/administración & dosificación , Ácido gammalinolénico/farmacología
12.
J Neurosci ; 21(10): 3342-9, 2001 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-11331363

RESUMEN

Central auditory relay synapses in mature animals follow high-frequency inputs for computation of sound localization. In immature mice, however, transmission at the calyx of Held synapse in auditory brainstem was inaccurate for high-frequency inputs because the summed slow synaptic potential components caused aberrant firings or blocked action potentials. As the mice matured, synaptic potentials became shorter, with smaller and faster NMDA receptor components, thereby establishing the precise one-to-one transmission for high-frequency inputs. Developmental acquisition of this high-fidelity transmission could be mimicked experimentally in immature mice by blocking NMDA receptors with d(-)2-amino-5-phosphonovaleric acid (d-APV). Furthermore, bilateral cochlear ablations at postnatal day 7 (P7) attenuated the developmental decrease of NMDA receptor expression and prevented the acquisition of high-fidelity transmission. We suggest that auditory activity, which begins at P10-P12 in mice, downregulates the expression of postsynaptic NMDA receptors, thereby contributing to the establishment of high-fidelity synaptic transmission.


Asunto(s)
Vías Auditivas/metabolismo , Tronco Encefálico/metabolismo , Regulación del Desarrollo de la Expresión Génica , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapsis/metabolismo , 2-Amino-5-fosfonovalerato/farmacología , Potenciales de Acción/fisiología , Envejecimiento/metabolismo , Animales , Vías Auditivas/citología , Tronco Encefálico/citología , Cóclea/fisiología , Núcleo Coclear/fisiología , Regulación hacia Abajo , Potenciales Postsinápticos Excitadores , Técnicas In Vitro , Ratones , Ratones Endogámicos C57BL , Neuronas/metabolismo , Técnicas de Placa-Clamp , Percepción de la Altura Tonal/fisiología , ARN Mensajero/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Receptores de N-Metil-D-Aspartato/genética , Transmisión Sináptica/fisiología
13.
J Am Coll Cardiol ; 17(2): 338-45, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1991889

RESUMEN

It has been suggested that histamine is involved in the pathogenesis of coronary spasm but its exact role remains unclear. H1 receptor stimulation of the coronary artery was performed with a selective intracoronary infusion of histamine (2 micrograms/min) in 21 patients with variant angina after blockade of the H2 receptor with cimetidine (25 mg/kg) and its effect on the coronary artery diameter was examined. Intracoronary injection of acetylcholine was also performed in 19 of the 21 patients. Ergonovine (0.2 mg) was intravenously administered in one patient. The coronary artery diameter was measured with cinevideodensitometric analysis. A mean plasma histamine concentration in the coronary sinus increased from 4 x 10(-9) to 7 x 10(-8) M 5 min after histamine infusion into the left coronary artery (n = 18). Coronary spasm was induced in 6 patients (29%) with histamine, in 18 (95%) with acetylcholine and in 1 with ergonovine. The effect of histamine on the luminal diameter was analyzed at the site of spasm in the 26 coronary arteries in which spasm was induced by acetylcholine or ergonovine. Of the 20 coronary arteries with a normal arteriogram or a fixed stenosis less than or equal to 50% of luminal diameter, histamine decreased the diameter in 4, increased it in 14 (70%) and caused no change in 2; of the 6 coronary arteries with a fixed stenosis greater than or equal to 75%, histamine decreased the diameter in 5 and increased it in 1. In the coronary arteries in which spasm was not induced by either acetylcholine or ergonovine, histamine increased the diameter, especially in those without advanced atherosclerosis.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Acetilcolina , Angina Pectoris Variable/etiología , Vasoespasmo Coronario/inducido químicamente , Vasos Coronarios/efectos de los fármacos , Histamina , Receptores Histamínicos H1/efectos de los fármacos , Vasoespasmo Coronario/fisiopatología , Ergonovina , Femenino , Histamina/fisiología , Humanos , Masculino , Persona de Mediana Edad , Receptores Histamínicos H1/fisiología , Vasodilatación/efectos de los fármacos
14.
J Am Coll Cardiol ; 12(4): 883-8, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3047196

RESUMEN

Intracoronary injection of acetylcholine has been shown to induce coronary spasm in patients with variant angina. To examine its sensitivity and specificity, incremental doses of acetylcholine (20, 50 and 100 micrograms into the left coronary artery and 20 and 50 micrograms into the right coronary artery) were injected into the coronary artery or arteries in 70 patients with variant angina (Group 1) (mean age 57 years) and 93 patients without variant angina or angina at rest (Group 2) (mean age 54 years). Forty patients of the latter group had atypical chest pain, 16 cardiomyopathy, 14 arrhythmia, 11 valvular disease, 7 stable effort angina due to advanced coronary artery disease, 3 congenital heart disease and 2 hypertension. A temporary cardiac pacemaker set at 40 to 50 beats/min was positioned in the right ventricle. Coronary spasm was defined as total occlusion or severe vasoconstriction associated with chest pain or ischemic ST changes on the electrocardiogram or both. In Group 1, acetylcholine induced spasm in 63 (90%) of the 70 patients in the artery or arteries predicted to be responsible for spontaneous attacks. In Group 2, acetylcholine induced coronary spasm only in one patient with effort angina and advanced coronary artery disease although lesser degrees of vasoconstriction (less than or equal to 75% of the luminal diameter) occurred in most patients after acetylcholine (specificity of acetylcholine thus was 99%). In conclusion, intracoronary injection of acetylcholine is sensitive and reliable for the induction of coronary spasm.


Asunto(s)
Acetilcolina , Vasoespasmo Coronario/inducido químicamente , Acetilcolina/administración & dosificación , Adulto , Anciano , Angina Pectoris Variable/fisiopatología , Enfermedad Coronaria/fisiopatología , Vasos Coronarios , Electrocardiografía , Reacciones Falso Negativas , Femenino , Humanos , Inyecciones , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
15.
J Am Coll Cardiol ; 14(1): 150-4, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2525582

RESUMEN

Plasma fibrinopeptide A levels, beta-thromboglobulin levels and platelet factor 4 levels were estimated by enzyme-linked immunosorbent assay before and after hyperventilation in 12 patients with coronary vasospastic angina and in 12 control subjects matched for age and gender. In all 12 study patients, anginal attacks accompanied by electrocardiographic (ECG) changes (ST elevation in 11 patients and ST depression in 1 patient) were induced by hyperventilation. Coronary angiography was performed on 11 of the 12 patients, and coronary artery spasm with the same ECG changes was induced by intracoronary injection of acetylcholine in all 11. The plasma fibrinopeptide A levels increased significantly from 2.0 +/- 0.4 to 10.0 +/- 2.4 ng/ml during the attack (p less than 0.001) in the study patients, but remained unchanged before and after hyperventilation in the control subjects. The plasma levels of beta-thromboglobulin and platelet factor 4 remained unchanged after hyperventilation in both groups. Our data indicate that coronary artery spasm may induce thrombin generation and trigger thrombus formation in the coronary artery.


Asunto(s)
Vasoespasmo Coronario/complicaciones , Fibrinógeno/metabolismo , Fibrinopéptido A/metabolismo , Cardiopatías/etiología , Hiperventilación/fisiopatología , Trombosis/etiología , Anciano , Angiografía Coronaria , Vasoespasmo Coronario/sangre , Vasoespasmo Coronario/diagnóstico por imagen , Vasoespasmo Coronario/fisiopatología , Electrocardiografía , Femenino , Cardiopatías/sangre , Humanos , Masculino , Persona de Mediana Edad , Trombosis/sangre , beta-Tromboglobulina/metabolismo
16.
J Am Coll Cardiol ; 19(4): 752-8, 1992 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-1545069

RESUMEN

To examine the constrictor response of the infarct-related stenotic coronary artery in comparison with that of noninfarct-related stenotic arteries, acetylcholine in maximal doses of 100 micrograms for the left and 50 micrograms for the right coronary artery was injected into the 16 infarct-related coronary arteries of 16 patients with previous myocardial infarction (group 1) and into 19 stenotic coronary arteries of 16 patients with stable angina without myocardial infarction (group 2). Acetylcholine's effects on lumen diameter and area were quantitatively analyzed at the stenotic segment and its proximal segment without significant stenosis. Acetylcholine decreased lumen diameter and area at the stenotic segments from 0.72 +/- 0.18 to 0.18 +/- 0.33 mm and from 0.45 +/- 0.22 to 0.10 +/- 0.22 mm2, respectively, in group 1 (both p less than 0.01) and from 0.75 +/- 0.22 to 0.49 +/- 0.30 mm and 0.48 +/- 0.29 to 0.26 +/- 0.23 mm2, respectively, in group 2 (both p less than 0.01). Acetylcholine decreased the diameter and area at the proximal segment from 2.71 +/- 0.75 to 2.38 +/- 0.6 mm and from 6.18 +/- 3.4 to 4.71 +/- 2.23 mm2, respectively, in group 1 (both p less than 0.01) and from 2.31 +/- 0.67 to 1.95 +/- 0.59 mm and from 4.5 +/- 2.97 to 3.22 +/- 1.96 mm2, respectively, in group 2 (both p less than 0.01). The changes in diameter and area at the stenotic segment in group 1 were significantly greater than those in group 2 (both p less than 0.01); there were no significant differences between groups in the changes at the proximal segment.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Acetilcolina/farmacología , Vasos Coronarios/fisiopatología , Infarto del Miocardio/fisiopatología , Vasoconstricción/fisiología , Angina de Pecho/fisiopatología , Constricción Patológica/diagnóstico por imagen , Constricción Patológica/fisiopatología , Angiografía Coronaria , Vasos Coronarios/efectos de los fármacos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagen , Vasoconstricción/efectos de los fármacos
17.
J Am Coll Cardiol ; 26(7): 1672-8, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7594102

RESUMEN

OBJECTIVES: The present study investigated the long-term changes in the electrocardiographic (ECG) hallmarks of the Japanese form of apical hypertrophy. BACKGROUND: Giant negative T waves and tall R waves in the left precordial leads are the ECG hallmarks of the Japanese form of apical hypertrophy. However, the long-term course is largely unknown. METHODS: Twenty-nine patients with apical hypertrophy (26 men, 3 women, mean age +/- SD 50.4 +/- 8.2 years) who showed left precordial giant negative T waves (< or = -10 mm) and tall R waves (> or = 26 mm) and spade configuration in the left ventriculogram were followed up for 10.9 +/- 3.7 years. RESULTS: The intermediate follow-up ECGs (5 to 9 years) showed disappearance of giant negative T waves in 31% and of tall R waves in lead V5 in 6%. At the long-term follow-up study (> or = 10 years), loss of giant negative T waves increased to 71%, with average T wave negativity in lead V4 or V5 decreasing from -16.5 +/- 5.1 to -6.9 +/- 4.2 mm. These T wave changes were associated with decreases in R wave amplitude in lead V5 from 40.7 +/- 9.6 to 26.1 +/- 13.8 mm, with loss of tall R waves in lead V5 in 38% of patients and development of abnormal Q waves in two patients. CONCLUSIONS: During the long-term follow-up of the Japanese form of apical hypertrophy, giant negative T waves disappeared in association with decreases in R wave amplitude in lead V5, indicating that these ECG hallmarks are clinical features that evolve progressively during the natural course of the disease.


Asunto(s)
Cardiomiopatía Hipertrófica/fisiopatología , Electrocardiografía , Adulto , Cardiomiopatía Hipertrófica/diagnóstico por imagen , Ecocardiografía , Femenino , Estudios de Seguimiento , Humanos , Japón , Masculino , Persona de Mediana Edad
18.
J Am Coll Cardiol ; 19(7): 1426-34, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1593035

RESUMEN

The epicardial coronary artery of patients with variant angina is hyperreactive to the constrictive effect of acetylcholine, but it is not known whether the coronary microvasculature also constricts in response to acetylcholine. Incremental doses of acetylcholine were injected into the left coronary artery of 57 patients with variant angina and with spasm in this artery. By measuring coronary sinus blood flow, coronary hemodynamic status just before angiographic documentation of spasm was examined. Acetylcholine induced spasm in the left coronary artery in all patients. It also decreased the diameter of the nonspasm artery by 36 +/- 19% from baseline. For all patients, coronary sinus blood flow was 89 +/- 38 ml/min at baseline and increased to 104 +/- 61 ml/min during an acetylcholine-induced anginal attack (p less than 0.01). In 10 patients with spasm in both the left anterior descending and left circumflex arteries (that is, multivessel spasm), coronary sinus blood flow decreased from 84 +/- 21 to 52 +/- 26 ml/min (p less than 0.01). In the other 47 patients with spasm in only one of these two arteries (that is, single-vessel spasm), coronary sinus blood flow increased from 90 +/- 41 to 115 +/- 61 ml/min (p less than 0.01) without change in the rate-pressure product. It is concluded that in patients with variant angina, acetylcholine induces spasm and constriction in the epicardial coronary artery, whereas it dilates the resistance vessels presumably through the release of the endothelium-dependent relaxing factor.


Asunto(s)
Acetilcolina , Angina Pectoris Variable/fisiopatología , Circulación Coronaria/fisiología , Vasoespasmo Coronario/inducido químicamente , Vasos Coronarios/fisiología , Óxido Nítrico/fisiología , Vasodilatación/fisiología , Cateterismo Cardíaco , Endotelio Vascular/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vasoconstricción/efectos de los fármacos , Vasodilatación/efectos de los fármacos
19.
J Am Coll Cardiol ; 12(5): 1184-92, 1988 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3170961

RESUMEN

Left ventricular wall motion abnormalities during an attack of coronary spasm induced by hyperventilation were examined with use of two-dimensional echocardiography in 27 patients with variant angina. Transient abnormal wall motion (asynergy) confined to one coronary artery region was found in 18 of the 27 patients and transient abnormal motion extending over more than one coronary artery region in the remaining 9 patients. Spasm of more than one major coronary artery was demonstrated separately by coronary arteriography during an attack induced by injection of acetylcholine or ergonovine in seven of the nine patients who manifested asynergy in more than one coronary artery region. In one patient, spasm was demonstrated in one major coronary artery, and the other coronary arteries were severely stenosed or occluded organically. In the remaining patient, acetylcholine was not injected into both arteries; however, the attack was sometimes associated with ST segment elevation in the anterior leads and at other times in the inferior leads. Therefore, simultaneous multivessel coronary spasm seems to have occurred in eight of the nine patients who exhibited asynergy in more than one coronary artery region. The 8 patients with simultaneous multivessel coronary spasm had a higher degree and longer duration of ST segment elevation and a higher incidence of arrhythmias during the attack induced by hyperventilation than did the 19 patients with single vessel coronary spasm, and all of them had no significant organic stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Angina Pectoris Variable/fisiopatología , Vasoespasmo Coronario/etiología , Hiperventilación/complicaciones , Angina Pectoris Variable/diagnóstico por imagen , Angiografía , Vasoespasmo Coronario/diagnóstico por imagen , Vasoespasmo Coronario/fisiopatología , Ecocardiografía , Electrocardiografía , Femenino , Corazón/fisiopatología , Humanos , Persona de Mediana Edad , Movimiento
20.
J Am Coll Cardiol ; 25(2): 342-8, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7829786

RESUMEN

OBJECTIVES: This study attempted to clarify the effects of human brain (B-type) natriuretic peptide on coronary artery diameter and coronary vascular resistance in humans. BACKGROUND: Brain natriuretic peptide induces vasodilation in systemic circulation by activating particulate guanylate cyclase of the vascular smooth muscle. METHODS: In 13 patients with normal coronary arteries and left ventricular function, brain natriuretic peptide was infused at 0.5 microgram/kg body weight per min for 4 min into the left main coronary artery (six patients, Group A) or into the pulmonary artery (seven patients, Group B). Systemic hemodynamic variables and coronary sinus blood flow were measured before and after the infusion. The lumen diameter of the left coronary artery was quantitatively measured. RESULTS: In both groups, brain natriuretic peptide significantly increased heart rate and decreased mean arterial pressure. Rate-pressure product remained unchanged in both groups. Brain natriuretic peptide decreased systemic vascular resistance index significantly in both groups (both p < 0.01 vs. baseline), and there was no difference in the effect between the groups. Brain natriuretic peptide decreased coronary vascular resistance in Group A (p < 0.01 vs. baseline) but did not affect coronary vascular resistance in Group B (p < 0.01 vs. Group A). The lumen diameters of the proximal and distal segments of the left coronary artery were increased significantly after brain natriuretic peptide in both groups. After infusion of brain natriuretic peptide, mean plasma level of brain natriuretic peptide in the coronary sinus increased from 36 to 130,411 pg/ml in Group A and from 64 to 12,329 pg/ml in Group B. CONCLUSIONS: Brain natriuretic peptide shows a vasodilator effect on the coronary artery system in humans. However, the effect does not appear uniformly but is seen preferentially in the epicardial coronary artery. The sensitivity of the coronary resistance vessels to brain natriuretic peptide is low compared with that of the resistance vessels of the systemic circulation.


Asunto(s)
Circulación Coronaria/efectos de los fármacos , Vasos Coronarios/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Proteínas del Tejido Nervioso/farmacología , Vasodilatadores/farmacología , Cateterismo Cardíaco , Angiografía Coronaria , Femenino , Humanos , Infusiones Intraarteriales , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico , Proteínas del Tejido Nervioso/administración & dosificación , Arteria Pulmonar , Resistencia Vascular/efectos de los fármacos , Vasodilatadores/administración & dosificación
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