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1.
Heart ; 96(21): 1716-22, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20956487

RESUMEN

BACKGROUND: Myeloperoxidase (MPO) is a leucocyte enzyme that catalyses the formation of a number of reactive oxidant species. OBJECTIVE: The purpose of this study is to evaluate the relationship between angiographic coronary plaque morphology in patients with unstable angina pectoris (UAP) or stable angina pectoris (SAP) and MPO levels. PATIENTS AND DESIGN: Plasma MPO levels on admission were measured in 236 patients with UAP, 146 with SAP and 85 control subjects using an ELISA kit. The angiographic morphology of the culprit lesion was classified into two types, simple or complex, based on the Ambrose classification. In addition, 61 atherectomy specimens obtained from a different cohort of patients with UAP and SAP were studied immunohistochemically for MPO. RESULTS: Median (IQR) plasma MPO levels in patients with UAP with a complex lesion were significantly higher than in patients with a simple lesion (41.9 (21.7­73.7) ng/ml vs 20.5 (15.9­27.9) ng/ml, p<0.0001), but there was no significant difference between the two groups in patients with SAP. On multivariate analysis, raised plasma MPO levels and Braunwald class III were independent factors for angiographically-detected complex lesions (adjusted OR 12.49, 95% CI 3.24 to 48.17, p=0.0002). In the atherectomy specimens the number of MPO-positive cells in patients with UAP with complex lesions was significantly higher (p<0.0005) than in patients with simple lesions. Moreover, in this cohort, plasma MPO levels were positively correlated with the number of MPO-positive cells in atherectomy specimens (R=0.42, p=0.024). CONCLUSIONS: This study shows that increased expression and plasma MPO levels are closely related to the presence of angiographically-detected complex lesion morphology in patients with UAP.


Asunto(s)
Angina Inestable/enzimología , Peroxidasa/metabolismo , Anciano , Angina de Pecho/diagnóstico por imagen , Angina de Pecho/enzimología , Angina de Pecho/cirugía , Angina Inestable/diagnóstico por imagen , Angina Inestable/cirugía , Aterectomía Coronaria , Biomarcadores/sangre , Biomarcadores/metabolismo , Estudios de Cohortes , Angiografía Coronaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Peroxidasa/sangre
2.
Neuroscience ; 162(4): 1333-8, 2009 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-19501134

RESUMEN

The effects of anti-parkinsonian drugs on bladder function have been controversial; namely, some aggravated while others alleviated bladder dysfunction in patients with Parkinson disease. These studies, however, did not consider the dose- and time-dependent effects. Therefore, we investigated these effects of apomorphine, an anti-parkinsonian drug and a nonselective dopamine receptor agonist, on the bladder function using normal conscious rats. Consecutive cycles of micturition were analyzed for 30-min periods before and after (over a 4-h period) s.c. administration of a single dose of 0.01 (low), 0.05 (medium), 0.5 (high) mg/kg of apomorphine or saline to the rats. Apomorphine administration produced various effects in relevant urodynamic parameters, although the monitored parameters remained unchanged in saline-administered rats. During filling, low-dose apomorphine induced initial decreases in voiding frequency (VF; defined as the number of voidings during a 15-min period). However, medium- and high-dose apomorphine dose-dependently induced initial increases in VF, and was followed by decreases in VF. These doses also induced initial increase in threshold pressure. During voiding, low-dose apomorphine induced initial increases in micturition volume (MV), which reflected an increase in bladder capacity (BC). However, medium- and high-dose apomorphine dose-dependently induced initial decreases in MV, and was followed by increases in MV. These doses also dose-dependently induced an initial increase in maximum bladder contraction pressure during the early phase after administration. The present study demonstrated that apomorphine displayed a dose- and time-dependent biphasic effect on the normal bladder filling function. These pharmacodynamic characteristics of apomorphine could be applicable to other anti-parkinsonian drugs such as levodopa and nonselective dopamine receptor agonists, and may account for the previous reported conflicting effects of anti-parkinsonian drugs on bladder dysfunction in patients with Parkinson disease, although it needs to be evaluated in disease status.


Asunto(s)
Antiparkinsonianos/efectos adversos , Apomorfina/efectos adversos , Agonistas de Dopamina/efectos adversos , Vejiga Urinaria/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Masculino , Ratas , Ratas Sprague-Dawley , Vejiga Urinaria/fisiología , Micción/efectos de los fármacos , Orina
3.
J Dent Res ; 88(2): 146-51, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19278986

RESUMEN

Higher 24-hour resin-dentin bond strengths are created when ethanol is used to replace water during wet bonding. This in vitro study examined if ethanol-wet-bonding can increase the durability of resin-dentin bonds over longer times. Five increasingly hydrophilic experimental resin blends were bonded to acid-etched dentin saturated with water or ethanol. Following composite build-ups, the teeth were reduced into beams for 24-hour microtensile bond strength evaluation, and for water-aging at 37 degrees C for 3, 6, or 12 months before additional bond strength measurements. Although most bonds made to water-saturated dentin did not change over time, those made to ethanol-saturated dentin exhibited higher bond strengths, and none of them fell over time. Decreased collagen fibrillar diameter and increased interfibrillar spacing were seen in hybrid layers created with ethanol-wet-bonding. Increases in bond strength and durability in ethanol-wet-bonding may be due to higher resin uptake and better resin sealing of the collagen matrix, thereby minimizing endogenous collagenolytic activities.


Asunto(s)
Recubrimiento Dental Adhesivo , Dentina , Etanol/química , Cementos de Resina/química , Grabado Ácido Dental , Resinas Compuestas , Análisis del Estrés Dental , Permeabilidad de la Dentina , Recubrimientos Dentinarios , Colágenos Fibrilares/química , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Dióxido de Silicio , Solubilidad , Resistencia a la Tracción , Factores de Tiempo , Agua/química , Humectabilidad , Circonio
4.
Heart ; 94(3): 316-21, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17591648

RESUMEN

BACKGROUND: Arachidonic acid (ARA) and docosahexaenoic acid (DHA) are important components of phospholipids and cell membranes. There has, however, been no clinical report on the direct effects of ARA and DHA on coronary circulation. OBJECTIVE: To evaluate the effects of ARA and DHA on coronary circulation using the measurement of coronary flow velocity reserve (CFVR) by transthoracic Doppler echocardiography (TTDE). METHODS: A double-blind, placebo-matched study of 28 Japanese elderly individuals (19 men, mean age 65 years) conducted to compare the effects of polyunsaturated fatty acids (PUFA; ARA 240 mg/day, DHA 240 mg/day) and placebo on CFVR. Coronary flow velocity (CFV) of the left anterior descending coronary artery was measured at rest and during hyperaemia by TTDE to determine CFVR. RESULTS: There were no significant differences in CFV at rest or during hyperaemia in CFVR at baseline in the two groups (PUFA versus placebo 17 (7 SD) versus 16 (6), 62 (20) versus 59 (12), and 3.85 (1.04) versus 3.98 (0.83) cm/s, respectively). After three months' supplementation, CFV during hyperaemia was significantly higher in the PUFA than in the placebo group (73 (19) versus 64 (12) cm/s, p<0.01) although no significant difference was found between the two groups in CFV at rest (17 (7) versus 16 (4) cm/s). CFVR thus significantly increased after PUFA consumption (3.85 (1.04) versus 4.46 (0.95), p = 0.0023). CONCLUSION: Three months' supplementation of PUFA increased CFVR in Japanese elderly individuals, which suggests beneficial effects of PUFA on the coronary microcirculation.


Asunto(s)
Ácido Araquidónico/farmacología , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Circulación Coronaria/efectos de los fármacos , Vasos Coronarios/efectos de los fármacos , Ácidos Docosahexaenoicos/farmacología , Anciano , Velocidad del Flujo Sanguíneo/fisiología , Circulación Coronaria/fisiología , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/fisiología , Ecocardiografía/métodos , Ecocardiografía Doppler en Color/métodos , Métodos Epidemiológicos , Membrana Eritrocítica/diagnóstico por imagen , Membrana Eritrocítica/efectos de los fármacos , Membrana Eritrocítica/fisiología , Femenino , Humanos , Masculino
5.
Pharmacogenomics J ; 8(1): 78-84, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17404580

RESUMEN

Recent clinical trials have clearly demonstrated that the administration with beta-blockers decreases the mortality in the patients with chronic heart failure (CHF). However, significant heterogeneity exists in the effectiveness of beta-blockers among individual cases. We focused on 39 polymorphisms in 16 genes related to adrenergic system and investigated their association with the response to beta-blockers among 80 patients with CHF owing to idiopathic dilated cardiomyopathy. The polymorphisms of NET T-182C (P=0.019), ADRA1D T1848A (P=0.023) and ADRA1D A1905G (P=0.029) were associated with the improvement of left ventricular fractional shortening (LVFS) by beta-blockers. Furthermore, combined genotype analysis of NET T-182C and ADRA1D T1848A revealed a significant difference in LVFS improvement among genotype groups (P=0.011). These results suggest that NET (T-182C) and ADRA1D (T1848A and A1905G) polymorphisms are predictive markers of the response to beta-blockers. Genotyping of these polymorphisms may provide clinical insights into an individual difference in the response to the beta-blocker therapy in CHF.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Cardiomiopatía Dilatada/tratamiento farmacológico , Cardiomiopatía Dilatada/genética , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática/genética , Receptores Adrenérgicos alfa 1/genética , Antagonistas Adrenérgicos beta/administración & dosificación , Anciano , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
6.
Heart ; 93(12): 1537-41, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17575334

RESUMEN

BACKGROUND: Previous studies have shown that recent activation of the inflammatory response in coronary atherosclerotic lesions contributes to rapid progressive plaque destabilisation. Neopterin, a by-product of the guanosine triphosphate pathway, is produced by activated macrophages and serves as an activation marker for monocytes/macrophages. OBJECTIVE: To elucidate the role of neopterin in coronary plaque destabilisation by immunohistochemical study of the presence of neopterin in coronary atherectomy specimens obtained from patients with stable angina pectoris (SAP) and unstable angina pectoris (UAP). PATIENTS AND METHODS: All patients underwent atherectomy of the primary atherosclerotic lesions responsible for SAP (n = 25) and UAP (n = 25). Frozen samples were studied with antibodies against smooth muscle cells, macrophages, T cells, neutrophils and neopterin. RESULTS: In 22/25 patients with UAP, abundant neopterin-positive macrophages were found at the sites of coronary culprit lesions. However, in 25 lesions from patients with SAP, only 11 lesions showed neopterin positivity. Quantitatively, the neopterin-positive macrophage score was significantly higher (p<0.001) in patients with UAP than in patients with SAP. Moreover, the neopterin-positive macrophage score showed a significant positive correlation with the number of neutrophils or T cells, respectively (neutrophils, r = 0.55, p<0.001; T cells, r = 0.70, p<0.001). CONCLUSIONS: Neopterin can be considered as one of the significant factors in the process of plaque inflammation and destabilisation in human coronary atherosclerotic lesions. Its exact role in the process needs to be investigated further.


Asunto(s)
Angina de Pecho/metabolismo , Angina Inestable/metabolismo , Enfermedad de la Arteria Coronaria/metabolismo , Vasos Coronarios/metabolismo , Neopterin/metabolismo , Angina de Pecho/patología , Angina Inestable/patología , Enfermedad de la Arteria Coronaria/patología , Femenino , Humanos , Inmunohistoquímica , Macrófagos/metabolismo , Masculino , Persona de Mediana Edad
7.
J Dent Res ; 85(11): 1016-21, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17062742

RESUMEN

The purpose of this study was to determine if hydrophobic resins can be coaxed into dentin wet with ethanol instead of water. The test hypothesis was that dentin wet with ethanol would produce higher bond strengths for hydrophobic resins than would dentin wet with water. This study examined the microtensile bond strength of 5 experimental adhesives (50 wt% ethanol/50% comonomers) of various degrees of hydrophilicity to acid-etched dentin that was left moist with water, moist with ethanol, or air-dried. Following composite buildups, hourglass-shaped slabs were prepared from the bonded teeth for microtensile testing. For all 3 types of dentin surfaces, higher bond strengths were achieved with increased resin hydrophilicity. The lowest bond strengths were obtained on dried dentin, while the highest bond strengths were achieved when dentin was bonded moist with ethanol. Wet-bonding with ethanol achieved higher bond strengths with hydrophobic resins than were possible with water-saturated matrices.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios/química , Cementos de Resina/química , Análisis de Varianza , Análisis del Estrés Dental , Dentina , Permeabilidad de la Dentina , Etanol , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Análisis de los Mínimos Cuadrados , Ensayo de Materiales , Tercer Molar , Solubilidad , Resistencia a la Tracción , Agua , Humectabilidad
9.
Heart ; 92(6): 759-62, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16216858

RESUMEN

OBJECTIVES: To investigate the relation between aortic stiffness and coronary flow reserve (CFR) in patients with coronary artery disease (CAD). DESIGN: Observational study. SETTING: Coronary care unit of a primary care hospital. PATIENTS: 192 consecutive patients who underwent coronary angiography. MAIN OUTCOME MEASURE: Brachial-ankle pulse wave velocity (ba-PWV), CFR, and severity of CAD. RESULTS: According to the angiographic findings, patients were divided into four subgroups: patients without significant stenosis (normal coronary artery (NCA) group, n = 28) and those with one vessel disease (1VD group, n = 92), two vessel disease (2VD group, n = 50), or three vessel disease (3VD group, n = 22). ba-PWV increased with the number of diseased vessels and was significantly correlated with the number of diseased vessels (NCA group v 1VD group v 2VD group v 3VD group: 1481 (252) v 1505 (278) v 1577 (266) v 1727 (347) cm/s, p < 0.001). CFR had a significant negative correlation with ba-PWV (r = -0.45, p < 0.0001). The diastolic to systolic velocity ratio obtained in 45 patients also was significantly correlated with ba-PWV (r = -0.35, p < 0.05). Multiple regression analysis showed that ba-PWV was an independent determinant of CFR (p < 0.01). CONCLUSIONS: Coronary flow is altered with aortic stiffening in patients with CAD. These results suggest one possible mechanism for recent reports that aortic stiffness is a key cardiovascular risk factor.


Asunto(s)
Enfermedades de la Aorta/fisiopatología , Enfermedad de la Arteria Coronaria/fisiopatología , Tobillo/irrigación sanguínea , Aorta/fisiopatología , Enfermedades de la Aorta/diagnóstico por imagen , Velocidad del Flujo Sanguíneo/fisiología , Arteria Braquial/fisiología , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Circulación Coronaria/fisiología , Estenosis Coronaria/fisiopatología , Elasticidad , Femenino , Humanos , Masculino , Microcirculación , Persona de Mediana Edad , Flujo Pulsátil/fisiología , Resistencia Vascular/fisiología
10.
Heart ; 92(4): 515-20, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15994912

RESUMEN

OBJECTIVE: To examine the effects of microbubble destruction with ultrasound (MB) combined with bone marrow derived mononuclear cell transplantation (BMT) into ischaemic tissues in rat hind limb ischaemia. METHODS AND RESULTS: Unilateral hind limb ischaemia was surgically induced in Lewis rats. At postoperative day 7, rats were randomly divided into three groups: a vehicle treated group, an ultrasound treated group, and an MB treated group. MB treatment increased vascular endothelial growth factor mRNA as assessed by real time polymerase chain reaction (3.0-fold, p < 0.05). At four weeks, the MB group had increases in laser Doppler blood flow index (LDBFI; 1.2-fold, p < 0.05), angiographically detectable collateral vessels (angiographic score: 1.4-fold, p < 0.01), and capillary to muscle fibre ratio (1.4-fold, p < 0.01) in ischaemic limbs compared with the vehicle treated group. No differences were seen between the vehicle and ultrasound treated groups. Secondly, rats were allocated to vehicle treatment, BMT (5 x 10(6) cells/rat), or a combination of MB and BMT (MB+BMT) at seven days after hind limb ischaemia. BMT treatment significantly increased LDBFI, angiographic score, and capillary to muscle fibre ratio compared with vehicle treatment. Interestingly, MB+BMT treatment produced significantly greater LDBFI (1.2-fold, p < 0.01), angiographic score (1.5-fold, p < 0.01), and capillary to muscle fibre ratio (1.5-fold, p < 0.05) than BMT treatment alone. CONCLUSIONS: MB may be a useful technique to enhance BMT induced neovascularisation.


Asunto(s)
Trasplante de Médula Ósea/métodos , Isquemia/terapia , Microburbujas , Músculo Esquelético/irrigación sanguínea , Neovascularización Fisiológica , Animales , Miembro Posterior/irrigación sanguínea , Miembro Posterior/patología , Inmunohistoquímica , Isquemia/diagnóstico por imagen , Masculino , Músculo Esquelético/patología , Distribución Aleatoria , Ratas , Ratas Endogámicas Lew , Ultrasonografía
11.
Gene Ther ; 13(4): 348-55, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16251994

RESUMEN

Cardiac activator protein-1 (AP-1), composed of c-Jun, is significantly activated by hypertension or angiotensin II (AngII). This study was undertaken to elucidate whether c-Jun could be the potential target for treatment of cardiac hypertrophy. We constructed recombinant adenovirus carrying dominant-negative mutant of c-Jun (Ad.DN-c-Jun). Using catheter-based technique of adenoviral gene transfer, we achieved global myocardial transduction of DN-c-Jun in rats, to specifically inhibit cardiac AP-1. (1) AngII (200 ng/kg/min) infusion in rats caused cardiac hypertrophy, increased cardiac p70S6 kinase activity by 1.3-fold (P<0.05) and enhanced the gene expression of cardiac hypertrophic markers. Ad.DN-c-Jun, which was transferred to the heart 2 days before AngII infusion, prevented cardiac hypertrophy (P<0.01), decreased p70S6 kinase phosphorylation (P<0.05), and suppressed cardiac gene expression of brain natriuretic peptide, collagen I, III, and IV, monocyte chemoattractant protein-1 (MCP-1) and plasminogen activator inhibitor-1 (PAI-1) (P<0.01). (2) In genetically hypertensive rats with cardiac hypertrophy, cardiac gene transfer of Ad.DN-c-Jun, without affecting hypertension, regressed cardiac hypertrophy (P<0.05), and suppressed p70S6 kinase phosphorylation by 20% (P<0.05) and suppressed the enhanced expression of collagen I, III, and IV, MCP-1 and PAI-1. These results provided the first evidence that in vivo blockade of cardiac c-Jun inhibits pathologic cardiac hypertrophy.


Asunto(s)
Cardiomegalia/prevención & control , Eliminación de Gen , Genes Dominantes , Terapia Genética/métodos , Factor de Transcripción AP-1/genética , Adenoviridae/genética , Angiotensina II/efectos adversos , Angiotensina II/metabolismo , Animales , Western Blotting/métodos , Cardiomegalia/etiología , Cardiomegalia/metabolismo , Quimiocina CCL2/metabolismo , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Colágeno Tipo IV/metabolismo , Vectores Genéticos/administración & dosificación , Vectores Genéticos/genética , Hipertensión/complicaciones , Hipertensión/metabolismo , Inyecciones , Masculino , Modelos Animales , Péptido Natriurético Encefálico/genética , Fosforilación , Inhibidor 1 de Activador Plasminogénico/metabolismo , Ratas , Ratas Sprague-Dawley , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Factor de Transcripción AP-1/metabolismo
12.
J Dent Res ; 84(11): 1075-8, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16246945

RESUMEN

The bond strengths of resins to caries-affected dentin are low. This could be due to weakened organic matrix. The purpose of this work was to determine if the ultimate tensile strength (UTS) of excavated carious dentin is weaker than that of normal dentin. Soft caries was excavated from extracted human molars, and the tooth was vertically sectioned into slabs. Each slab was trimmed to an hourglass shape, parallel or perpendicular to the tubule direction. Half of the specimens were mineralized, while the other half were completely demineralized in EDTA. ANOVA on ranks showed that the three-factor interactions (mineralization, caries, tubule direction) were all significant (p < 0.0001), indicating that mineralization and tubule direction gave different UTS results in normal and caries-affected dentin. No significant differences were seen between the UTS of normal and and that of caries-affected demineralized dentin in the parallel or perpendicular group. The matrix of demineralized caries-affected dentin was as strong as that of normal demineralized dentin when tested in the same direction.


Asunto(s)
Caries Dental/fisiopatología , Dentina/fisiopatología , Quelantes/farmacología , Técnica de Descalcificación , Caries Dental/patología , Dentina/efectos de los fármacos , Dentina/ultraestructura , Ácido Edético/farmacología , Humanos , Resistencia a la Tracción , Remineralización Dental
13.
Insect Mol Biol ; 14(5): 483-91, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16164604

RESUMEN

We report the characterization of 11 antioxidant genes from the tsetse fly Glossina m. morsitans. Through similarity searches which detected homology we suggest that these genes consist of two superoxide dismutases (one with a putative signal peptide), three thioredoxin peroxidases (one with a putative signal peptide), three peroxiredoxins, one further signal peptide-containing peroxidase with its closest similarity to a glutathione peroxidase, one catalase and one thioredoxin reductase. We describe the changes occurring in the expression levels of these genes during fly development, in different adult tissues, in the adult midgut through the digestive cycle and following trypanosome infection. Overall, nine of the 11 genes studied showed responses to changes in physiological circumstance, with the peroxiredoxin group showing the smallest variations throughout.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica/fisiología , Regulación Enzimológica de la Expresión Génica/fisiología , Proteínas de Insectos/biosíntesis , Oxidorreductasas/biosíntesis , Moscas Tse-Tse/enzimología , Animales , Femenino , Larva/metabolismo , Masculino , Estrés Oxidativo , Oxidorreductasas/genética , Pupa/fisiología , Distribución Tisular , Trypanosoma
14.
Heart ; 91(8): 1080-5, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16020603

RESUMEN

BACKGROUND: It is well known that angiotensin converting enzyme (ACE) inhibitors and angiotensin II type 1 (AT1) receptor blockers (ARBs) prevent left ventricular (LV) remodelling after myocardial infarction (MI). However, it is still not clear whether inhibition of the AT1 receptor is enough to prevent LV remodelling after MI. OBJECTIVE: To elucidate the effects of ACE inhibitors that are not mediated by the AT1 receptor on LV remodelling, MI was experimentally induced in wild-type (WT-MI) mice and AT1 receptor knockout (KO-MI) mice. METHODS: Mice were divided into six groups: WT-control, KO-control, WT-MI, KO-MI, WT-MI treated with an ACE inhibitor, and KO-MI treated with an ACE inhibitor. Four weeks after MI, cardiac function was assessed by Doppler echocardiography and non-infarcted myocardial mRNA expression by northern blot analysis. RESULTS: Cardiac function decreased significantly in the MI groups compared with the sham operated groups. Additionally, in the MI groups end diastolic dimension, E wave velocity, the ratio of peak velocity of E wave to A wave, deceleration rate of E wave, and mRNA expression of atrial natriuretic peptide, brain natriuretic peptide, and collagens I and III increased significantly compared with the sham groups. LV remodelling after MI was prevented in KO-MI mice compared with WT-MI mice. ACE inhibitor administration significantly attenuated progressive LV remodelling in both WT and KO-MI groups. CONCLUSION: ACE inhibitors can prevent the LV remodelling process that accompanies cardiac dysfunction after MI, even in AT1 KO mice. These findings suggest that ACE inhibitors prevent LV remodelling after MI by mechanisms other than inhibition of angiotensin AT1 receptor mediated effects.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Receptor de Angiotensina Tipo 1/metabolismo , Remodelación Ventricular/efectos de los fármacos , Animales , Northern Blotting , Ecocardiografía Doppler , Ventrículos Cardíacos/patología , Hemodinámica/fisiología , Ratones , Ratones Noqueados , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Tamaño de los Órganos/fisiología , ARN Mensajero/metabolismo , Disfunción Ventricular Izquierda/patología
16.
Neuroscience ; 132(4): 1017-26, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15857706

RESUMEN

Effects of i.c.v. and i.t. administration of (3SR,4aRS,6RS,8aRS)-6-[2-(1H-tetrazol-5-yl)ethyl]decahydroisoquinoline-3-carboxylic acid (LY215490), a competitive alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor antagonist and MK-801, a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist on the micturition reflex were evaluated in urethane-anesthetized rats, to determine if glutamatergic mechanisms in brain as well as spinal cord are important for the control of micturition. I.c.v. or i.t. injection of LY215490 in low doses (0.01-0.03 microg) did not change rhythmic bladder or external urethral sphincter (EUS) electromyogram (EMG) activity during continuous cystometrograms (CMGs; 0.21 ml/min), whereas higher doses (0.1-1 microg) markedly suppressed these responses. During single CMGs (0.04 ml/min), 0.1-1 microg i.c.v. or 0.1-10 microg i.t. doses increased volume threshold and pressure threshold for inducing micturition, and decreased bladder contraction amplitude and voiding efficiency. MK-801 in low doses (0.6 microg i.c.v. or 0.6-1.8 microg for i.t.) did not change bladder contraction amplitude or EUS EMG activity during continuous CMGs, whereas higher doses 6-60 microg markedly suppressed these responses. During single CMGs, MK-801 (6-60 microg i.c.v. or 60 microg i.t.) increased volume threshold and pressure threshold, and decreased voiding efficiency and bladder contraction amplitude. Pretreatment i.c.v. with MK-801 in a dose 1.8 microg which alone had little effect on bladder contraction amplitude and EUS EMG activity, markedly enhanced depressant effects of LY215490 (0.03 microg i.c.v.) on these responses. Administration of same doses of drugs by i.t. route did not elicit a similar synergistic interaction. These data indicate that in urethane-anesthetized rats glutamatergic mechanisms in brain and spinal cord are essential for controlling micturition and that interactions between AMPA and NMDA glutamatergic transmission are important at supraspinal but not spinal sites.


Asunto(s)
Maleato de Dizocilpina/administración & dosificación , Antagonistas de Aminoácidos Excitadores/administración & dosificación , Isoquinolinas/administración & dosificación , N-Metilaspartato/metabolismo , Médula Espinal/efectos de los fármacos , Tetrazoles/administración & dosificación , Micción/fisiología , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/metabolismo , Anestesia , Anestésicos Intravenosos/farmacología , Animales , Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Electromiografía , Femenino , Ácido Glutámico/metabolismo , Inyecciones Intraventriculares , Inyecciones Espinales , Vías Nerviosas/fisiología , Ratas , Ratas Sprague-Dawley , Médula Espinal/fisiología , Uretano/farmacología , Vejiga Urinaria/efectos de los fármacos , Vejiga Urinaria/inervación
17.
Heart ; 91(12): 1578-83, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15797931

RESUMEN

OBJECTIVE: To assess the role of intravenous myocardial contrast echocardiography (MCE) in predicting functional recovery and regional or global left ventricular (LV) remodelling after acute myocardial infarction (AMI) compared with low dose dobutamine stress echocardiography (LDSE). METHODS: 21 patients with anterior AMI and successful primary angioplasty underwent MCE and LDSE during the subacute stage (2-4 weeks after AMI). Myocardial perfusion and contractile reserve were assessed in each segment (12 segment model) with MCE and LDSE. The 118 dyssynergic segments in the subacute stage were classified as recovered, unchanged, or remodelled according to wall motion at six months' follow up. Percentage increase in LV end diastolic volume (%DeltaEDV) was also calculated. RESULTS: The presence of perfusion was less accurate than the presence of contractile reserve in predicting regional recovery (55% v 81%, p < 0.0001). However, the absence of perfusion was more accurate than the absence of contractile reserve in predicting regional remodelling (83% v 48%, p < 0.0001). The number of segments without perfusion was an independent predictor of %DeltaEDV, whereas the number of segments without contractile reserve was not. The area under the receiver operating characteristic curve showed that the number of segments without perfusion predicted substantial LV dilatation (%DeltaEDV > 20%) more accurately than did the number of segments without contractile reserve (0.88 v 0.72). CONCLUSION: In successfully revascularised patients with AMI, myocardial perfusion assessed by MCE is predictive of regional and global LV remodelling rather than of functional recovery, whereas contractile reserve assessed by LDSE is predictive of functional recovery rather than of LV remodelling.


Asunto(s)
Ecocardiografía de Estrés/normas , Ecocardiografía/normas , Infarto del Miocardio/diagnóstico por imagen , Remodelación Ventricular/fisiología , Anciano , Ecocardiografía/métodos , Ecocardiografía de Estrés/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Contracción Miocárdica/fisiología , Infarto del Miocardio/fisiopatología , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Volumen Sistólico/fisiología
18.
Heart ; 91(12): 1595-600, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15797934

RESUMEN

OBJECTIVE: To examine the effects of eplerenone, a selective aldosterone blocker, on cardiac function after myocardial infarction (MI) and myocardial remodelling related transcriptional factors and mRNA expression in non-infarcted myocardium. METHODS: MI was induced by ligation of the coronary artery in Wistar rats. Rats were randomly assigned to a vehicle treated group or an eplerenone treated group (100 mg/kg/day). RESULTS: At four weeks after MI, left ventricular (LV) end diastolic pressure, LV weight, and LV end diastolic dimension were increased in MI rats. Eplerenone significantly reduced the increase in LV end diastolic pressure, LV weight, and LV end diastolic dimension. In the MI rats the decreased ejection fraction indicated systolic dysfunction and the increased E wave to A wave ratio and E deceleration rate indicated diastolic dysfunction. Eplerenone significantly attenuated this systolic and diastolic dysfunction. Myocardial interstitial fibrosis, transcriptional activities of activator protein 1 and nuclear factor kappaB, and mRNA expression of monocyte chemoattractant protein 1, plasminogen activator inhibitor 1, atrial natriuretic peptide, brain natriuretic peptide, and collagen types I and III were significantly increased at four weeks after MI. Eplerenone significantly attenuated interstitial fibrosis and suppressed transcriptional activity and mRNA expression of these genes. CONCLUSIONS: When administered after MI, eplerenone prevents cardiac remodelling accompanied by systolic and diastolic dysfunction and inhibits abnormal myocardial transcriptional activities and gene expression.


Asunto(s)
Antagonistas de Receptores de Mineralocorticoides/farmacología , Infarto del Miocardio/metabolismo , ARN Mensajero/metabolismo , Espironolactona/análogos & derivados , Factores de Transcripción/genética , Remodelación Ventricular/efectos de los fármacos , Animales , Presión Sanguínea/efectos de los fármacos , Northern Blotting , Peso Corporal/efectos de los fármacos , Vasos Coronarios , Ecocardiografía Doppler , Eplerenona , Corazón/efectos de los fármacos , Ventrículos Cardíacos , Ligadura/métodos , Masculino , Tamaño de los Órganos , Distribución Aleatoria , Ratas , Ratas Wistar , Espironolactona/farmacología , Factores de Transcripción/efectos de los fármacos
19.
J Oral Rehabil ; 31(11): 1061-7, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15525383

RESUMEN

The purpose of this study was to evaluate the effect of 2-hydroxyethyl methacrylate (HEMA) application on the micro-tensile bond strength of resin composite to demineralized dentin. Artificially demineralized lesions were formed on bovine dentin surfaces and treated with 10, 30, 50, 70 and 100 wt% HEMA aqueous solution. The surfaces were then applied and covered with SE Bond and AP-X according to the manufacturer's instruction. After immersion in 37 degrees C water for 24 h, bond strength were measured using a universal testing machine. Bond strengths to both demineralized dentin and normal dentin, without HEMA application, were also measured. Scanning electron microscopic (SEM) observation and confocal laser scanning microscopy (CLSM) analysis at the resin-dentin interface were also performed. The bond strength data were statistically compared with anova and Scheffe's test (P < 0.05). Bond strength to demineralized dentin treated with over 30 wt% HEMA aqueous solution were significantly higher than that to demineralized dentin without HEMA application, but significantly lower than that to normal dentin. SEM observation revealed that the hybrid layer and resin-tags thickened and lengthened with HEMA application. In CLSM, the diffusion of adhesive primer into demineralized dentin increased with HEMA application. These results indicated that HEMA application might increase the bond strength to demineralized dentin by the enhancement of resin monomer penetration of HEMA.


Asunto(s)
Recubrimiento Dental Adhesivo , Dentina , Metacrilatos/uso terapéutico , Cementos de Resina , Animales , Bovinos , Microscopía Confocal , Microscopía Electrónica de Rastreo , Resistencia a la Tracción
20.
Heart ; 90(11): 1275-80, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15486119

RESUMEN

OBJECTIVES: To clarify the value of cycle dependent variation of myocardial integrated backscatter (CV-IB) analysis, which non-invasively measures acoustic properties of the myocardium, for early detection of cardiac involvement in patients with sarcoidosis. METHODS: The study population consisted of 22 consecutive patients with biopsy proven sarcoidosis who did not have any abnormal findings on conventional two dimensional echocardiogram. Cardiac sarcoidosis was diagnosed by radionuclide testing including thallium-201 scintigraphy, gallium-67 scintigraphy, and cardiac fluorine-18-deoxyglucose positron emission tomography. The magnitude and delay of the CV-IB were analysed in the basal mid septum and the basal mid posterior wall of the left ventricle of all patients. RESULTS: The patients were divided into two groups: 8 patients with cardiac involvement and 14 patients without cardiac involvement. In the basal septum, a major reduction in the magnitude (mean (SD) 1.8 (4.4) v 6.6 (1.3), p = 0.012) and an increase in the time delay (1.3 (0.5) v 1.0 (0.1), p = 0.038) of CV-IB were observed in patients with cardiac sarcoidosis even in the absence of two dimensional echocardiographic abnormalities. The sensitivity for detecting cardiac involvement was such that the magnitude of CV-IB in the basal septum discriminated 75% of patients with cardiac sarcoidosis from those with non-cardiac sarcoidosis, whereas two dimensional echocardiographic parameters did not discriminate between these two groups. CONCLUSIONS: The CV-IB is decreased in the basal septum in patients with cardiac sarcoidosis even in the absence of two dimensional echocardiographic abnormalities. Analysis of CV-IB may be a useful method to detect early myocardial involvement in patients with sarcoidosis.


Asunto(s)
Cardiomiopatías/diagnóstico por imagen , Sarcoidosis/diagnóstico por imagen , Diagnóstico Precoz , Ecocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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