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1.
Ir Med J ; 111(4): 732, 2018 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-30486643

RESUMEN

Introduction Following musculoskeletal injury patient education is essential to help patients understand their treatment. Many attend the orthopaedic fracture clinic with multiple questions related to their diagnosis and treatment. Aim To assess trauma patients' attitudes towards online health information and a specific orthopaedic patient information website. Methods A validated questionnaire was distributed over 5 consecutive clinics, with questions based on previous online experiences & www.myorthoclinic.com. Results One hundred six patients completed the survey. Seventy-one percent trusted the internet whereas 83% trusted the information provided by the website. Eighty-three percent felt encouraged to take action to benefit their health. Eighty-seven percent felt that there was a wide range of information provided. Seventy-two percent agreed that they learnt something new. Discussion Patients attending the trauma clinic have benefited from the 'prescribing' of a dedicated orthopaedic trauma website. This low-cost concept utilises minimal resources, requires little effort to implement and is applicable to all specialties.


Asunto(s)
Actitud Frente a la Salud , Educación a Distancia , Sistemas de Información en Salud , Sistema Musculoesquelético/lesiones , Educación del Paciente como Asunto , Heridas y Lesiones/psicología , Adolescente , Adulto , Niño , Femenino , Humanos , Internet , Masculino , Persona de Mediana Edad , Educación del Paciente como Asunto/estadística & datos numéricos , Encuestas y Cuestionarios , Heridas y Lesiones/diagnóstico , Heridas y Lesiones/terapia , Adulto Joven
2.
J Endocrinol Invest ; 39(12): 1435-1443, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27444618

RESUMEN

PURPOSE: To evaluate the association of galectin-3 (Gal3) with obesity and inflammatory status in a cohort of metabolically healthy, predominantly African-American women with varying cardiovascular disease (CVD) risk as determined by CRP levels. METHODS: We assessed the association between BMI and serum levels of Gal3, IL-6, CRP, and adiponectin in metabolically healthy women (N = 97) to determine the overall association between Gal3, obesity, and inflammation in groups at different CVD risk. RESULTS: Obese women had significantly higher serum Gal3 compared to non-obese participants (P = 0.0016), although Gal3 levels were comparable among different classes of obesity. BMI (R 2 = 0.1406, P = 0.0013), IL-6 (R 2 = 0.0689, P = 0.035), and CRP (R 2 = 0.0468, P = 0.0419), but not adiponectin, positively predicted the variance of Gal3 levels in the total study population. However, the predicting effect of BMI (R 2 = 0.2923, P = 0.0125) and inflammation (R 2 = 0.3138, P = 0.038) on Gal3 was only present in women at low/moderate risk of CVD (CRP ≤ 3 µg/mL). CONCLUSIONS: Gal3 is positively correlated with obesity and inflammation in women, while the presence of elevated CVD risk may disturb the strength of Gal3 as a biomarker of inflammation.


Asunto(s)
Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Enfermedades Cardiovasculares/diagnóstico , Galectina 3/sangre , Inflamación/diagnóstico , Interleucina-6/sangre , Obesidad/complicaciones , Adiposidad , Adulto , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/etiología , Estudios de Casos y Controles , Femenino , Humanos , Inflamación/sangre , Inflamación/etiología , Obesidad/sangre , Factores de Riesgo
3.
Front Artif Intell ; 4: 765210, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34765970

RESUMEN

Background: CTG remains the only non-invasive tool available to the maternity team for continuous monitoring of fetal well-being during labour. Despite widespread use and investment in staff training, difficulty with CTG interpretation continues to be identified as a problem in cases of fetal hypoxia, which often results in permanent brain injury. Given the recent advances in AI, it is hoped that its application to CTG will offer a better, less subjective and more reliable method of CTG interpretation. Objectives: This mini-review examines the literature and discusses the impediments to the success of AI application to CTG thus far. Prior randomised control trials (RCTs) of CTG decision support systems are reviewed from technical and clinical perspectives. A selection of novel engineering approaches, not yet validated in RCTs, are also reviewed. The review presents the key challenges that need to be addressed in order to develop a robust AI tool to identify fetal distress in a timely manner so that appropriate intervention can be made. Results: The decision support systems used in three RCTs were reviewed, summarising the algorithms, the outcomes of the trials and the limitations. Preliminary work suggests that the inclusion of clinical data can improve the performance of AI-assisted CTG. Combined with newer approaches to the classification of traces, this offers promise for rewarding future development.

4.
Gene Ther ; 15(3): 224-32, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18033310

RESUMEN

Vessel wall inflammation and matrix destruction are critical to abdominal aortic aneurysm (AAA) formation and rupture. We have previously shown that urokinase plasminogen activator (uPA) is highly expressed in experimental AAA and is essential for AAA formation and expansion. In this study, we examined the effects of overexpression of a natural inhibitor of uPA, plasminogen activator inhibitor-1 (PAI-1), on the development of angiotensin (Ang) II-induced AAA in ApoE-deficient (ApoE(-/-)) mice. Mice were treated with recombinant adenovirus containing either the human PAI-1 gene (Ad5.CMV.PAI-1) or the luciferase gene (Ad5.CMV.Luc) delivered either locally by intra-adventitial injection or systemically by tail vein injection. Our results show that local delivery of the PAI-1 gene completely prevented AAA formation (0 vs 55.6% in Ad5.CMV.Luc controls, P<0.05). In contrast, systemic delivery of the PAI-1 gene did not affect AAA incidence (78 vs 90% in Ad5.CMV.Luc controls, P=0.125). Local delivery of the PAI-1 gene 2 weeks after Ang II infusion prevented further expansion of small aneurysms, but had no significant effect on the progression of larger aneurysms. These data suggest that local PAI-1 gene transfer could be used to stabilize small AAA and reduce the rate of expansion and risk of rupture.


Asunto(s)
Aneurisma de la Aorta Abdominal/prevención & control , Terapia Genética/métodos , Inhibidor 1 de Activador Plasminogénico/genética , Transducción Genética/métodos , Angiotensina II , Animales , Aorta Abdominal/enzimología , Aorta Abdominal/patología , Aneurisma de la Aorta Abdominal/metabolismo , Aneurisma de la Aorta Abdominal/patología , Apolipoproteínas E/genética , Aterosclerosis/enzimología , Aterosclerosis/patología , Citomegalovirus/genética , Fibrosis , Expresión Génica , Vectores Genéticos/administración & dosificación , Vectores Genéticos/genética , Luciferasas/genética , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones , Ratones Noqueados , Inhibidor 1 de Activador Plasminogénico/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo
5.
Opt Express ; 15(9): 5742-53, 2007 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-19532832

RESUMEN

We describe a static aperture-coded, dispersive longwave infrared (LWIR) spectrometer that uses a microbolometer array at the detector plane. The two-dimensional aperture code is based on a row-doubled Hadamard mask with transmissive and opaque openings. The independent column code nature of the matrix makes for a mathematically well-defined pattern that spatially and spectrally maps the source information to the detector plane. Post-processing techniques on the data provide spectral estimates of the source. Comparative experimental results between a slit and coded aperture for emission spectroscopy from a CO(2) laser are demonstrated.

6.
J Bone Joint Surg Br ; 89(10): 1396-401, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17957085

RESUMEN

We compared the bulking and tensile strength of the Pennington modified Kessler, Cruciate and the Savage repairs in an ex vivo model. A total of 60 porcine tendons were randomised to three groups, half repaired using a core suture alone and the remainder employing a core and peripheral technique. The tendons were distracted to failure. The force required to produce a 3 mm gap, the ultimate strength, the mode of failure and bulking for each repair were assessed. We found that there was a significant increase in strength without an increase in bulk as the number of strands increased. The Cruciate repair was significantly more likely to fail by suture pullout than the Pennington modified Kessler or Savage repairs. We advise the use of the Savage repair, especially in the thumb, and a Cruciate when a Savage is not possible. The Pennington modified Kessler repair should be reserved for multiple tendon injuries.


Asunto(s)
Técnicas de Sutura , Traumatismos de los Tendones/cirugía , Cicatrización de Heridas/fisiología , Animales , Distribución Aleatoria , Suturas , Porcinos , Resistencia a la Tracción
7.
J Hand Surg Asian Pac Vol ; 22(1): 83-87, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28205470

RESUMEN

BACKGROUND: Finger injuries are common in the sport of hurling. Injury to the little finger distal interphalangeal joint (DIPJ) often occurs when a high dropping ball impacts on the outstretched finger. The little finger contributes to approximately 15% of grip strength. Injury therefore results in reduced grip strength and may impair the ability of players to grip or catch a ball. METHODS: Six elite hurlers with post-traumatic arthritis of their non-dominant little finger DIPJ underwent arthrodesis in 30 degrees of flexion. Kirchner wires were inserted for up to 8 weeks to achieve fusion of the joint. Patients were evaluated after recovery using a dynamometer to assess grip strength, the DASH questionnaire and a sport specific questionnaire. RESULTS: All arthrodeses achieved bony union without complication. All patients reported a resolution of their pain and recovery in their ability to catch & retain a ball. Measurements of grip strengths were comparable between hands. DASH scores improved by up to 47 points. All scores were less than 5 at final follow-up. CONCLUSIONS: Grip strength decreases when fingers are immobilized in full extension. In sports that require catching or gripping a ball or a bat, arthrodesis of the DIP joint in flexion can improve grip strength and hand function. Fusion in 30 degrees of flexion for hurlers results in restoration of function and resolution of pain. Little finger DIPJ arthrodesis is a valid method of treating posttraumatic arthritis in ball and bat sports.


Asunto(s)
Artritis/cirugía , Artrodesis/métodos , Traumatismos en Atletas/complicaciones , Traumatismos de los Dedos/complicaciones , Articulaciones de los Dedos/cirugía , Fracturas no Consolidadas/complicaciones , Rango del Movimiento Articular/fisiología , Adolescente , Adulto , Artritis/diagnóstico , Artritis/etiología , Traumatismos en Atletas/diagnóstico , Traumatismos de los Dedos/diagnóstico , Traumatismos de los Dedos/fisiopatología , Articulaciones de los Dedos/diagnóstico por imagen , Articulaciones de los Dedos/fisiopatología , Fracturas no Consolidadas/diagnóstico , Fuerza de la Mano , Humanos , Masculino , Radiografía , Encuestas y Cuestionarios , Adulto Joven
8.
Cardiovasc Res ; 51(2): 351-8, 2001 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-11470475

RESUMEN

OBJECTIVE: The present study was to examine whether endogenous nitric oxide (NO) plays a role in the regulation of vascular stiffness. METHODS: Pulse wave velocity (PWV) was determined as the time delay between the foot of pressure waves recorded simultaneously at the aortic arch and abdominal aorta (just above the bifurcation) in anesthetized Sprague-Dawley rats. A decrease in vascular compliance results in an increase in PWV. RESULTS: A bolus injection of a NO synthase inhibitor, L-NAME (30 mg/kg), significantly increased PWV, accompanied by an increase in blood pressure. Since changes in blood pressure are known to affect PWV, phenylephrine (PE) was administered to mimic the blood pressure changes induced by L-NAME, thus compensating for the pressure-dependent component of the PWV changes. At each given level of mean arterial pressure (MAP), PWV was significantly higher with L-NAME than with PE treatment, suggesting that acute withdrawal of endogenous NO reduces aortic compliance independent of changes in MAP. In rats chronically treated with L-NAME (0.5 g/l in drinking water) for 3 weeks, PWV was even higher than those acutely treated with L-NAME (at MAP=150 mmHg). This additional increase in vascular stiffness may be due to the remodeling of the vascular wall as a result of chronic NOS inhibition and hypertension. CONCLUSION: These data demonstrate that NO modulates vascular compliance independent of blood pressure changes and that an intact endogenous NO system is required to maintain normal vascular compliance.


Asunto(s)
Endotelio Vascular/efectos de los fármacos , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Resistencia Vascular/efectos de los fármacos , Análisis de Varianza , Animales , Aorta Abdominal , Aorta Torácica , Inhibidores Enzimáticos/farmacología , Masculino , Fenilefrina/farmacología , Ratas , Ratas Sprague-Dawley , Vasoconstrictores/farmacología
9.
Cardiovasc Res ; 43(3): 658-65, 1999 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-10690337

RESUMEN

There is convincing evidence that the prevalence of erectile dysfunction is increased among men with ischaemic heart disease. This association may be attributed to the fact that both erectile dysfunction and ischaemic heart disease share similar risk factors (e.g. hypertension, dyslipidaemia, diabetes and smoking). Nitric oxide (NO) activity is adversely affected, in penile and vascular tissue, by these risk factors. It is therefore not surprising that a defect in NO activity is thought to play a role in the pathogenesis of both erectile dysfunction and ischaemic heart disease. We consider this evidence and propose that defective NO activity provides a unifying explanation for the association between these two conditions. Further research in this area may improve our understanding of the pathogenesis of cardiovascular diseases as a whole.


Asunto(s)
Enfermedades Cardiovasculares/fisiopatología , Músculo Liso Vascular/fisiopatología , Óxido Nítrico/fisiología , Erección Peniana , Pene/irrigación sanguínea , Enfermedades Cardiovasculares/metabolismo , Diabetes Mellitus/metabolismo , Diabetes Mellitus/fisiopatología , Endotelina-1/metabolismo , Humanos , Hipercolesterolemia/metabolismo , Hipercolesterolemia/fisiopatología , Masculino , Músculo Liso Vascular/metabolismo , Pene/inervación
10.
J Invest Dermatol ; 81(5): 446-8, 1983 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6631056

RESUMEN

The effect of a skin moisturizer on the water content distribution in human stratum corneum was examined from the rate of water loss from the skin surface. An increase of 9% in the water content was calculated from the water loss data. This increase was not evenly distributed across the tissue. Most of the increase occurred near the skin surface. In the first one-tenth of the stratum corneum the increase was estimated to be about 100%.


Asunto(s)
Agua Corporal/metabolismo , Piel/metabolismo , Difusión , Femenino , Humanos , Piel/efectos de los fármacos
11.
Atherosclerosis ; 144(2): 303-13, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10407491

RESUMEN

Epidemiological data indicate that estrogens significantly reduce the risk of morbidity and mortality due to cardiovascular diseases in postmenopausal women. Although numerous animal studies demonstrated inhibition of early atheromatous lesion formation by estrogen treatment in several species, information about the potential benefits of estrogens on complex, advanced atherosclerotic lesions is still lacking. The present study was designed to test whether chronic treatment with 17 beta-estradiol affects hyperglycemia-induced premature advanced lesion formation in 40-week-old male apolipoprotein E-deficient (Apo E-KO) mice. In order to accelerate advanced lesion formation, we treated male Apo E-KO mice with streptozotocin (STZ) at the age of 6 weeks. Two weeks later the STZ-treated mice received a slow release pellet containing either 17 beta-estradiol or placebo. STZ treatment caused sustained hyperglycemia without changes in serum total cholesterol or triglyceride levels compared to citrate control mice. STZ-treated Apo E-KO mice developed significantly more lesions in some (but not all) parts of the aorta and its main branches, and caused premature calcified cartilaginous metaplasia in the lesions of the proximal aorta. Chronic treatment with 17 beta-estradiol lead to a significant decrease in blood glucose and triglyceride levels, reduced the lesion area in all vascular segments studied and prevented cartilaginous metaplasia in STZ-treated Apo E-KO mice. The results of this study show that STZ treatment leads to significant acceleration of atherosclerotic lesion formation and premature occurrence of calcified cartilaginous areas in Apo E-KO mice, which could be effectively prevented by chronic estrogen treatment.


Asunto(s)
Apolipoproteínas E/genética , Arteriosclerosis/prevención & control , Calcinosis/prevención & control , Diabetes Mellitus Experimental/prevención & control , Estradiol/farmacología , Animales , Aorta/patología , Arteriosclerosis/genética , Arteriosclerosis/patología , Calcinosis/genética , Calcinosis/patología , Cartílago/patología , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patología , Angiopatías Diabéticas/genética , Angiopatías Diabéticas/patología , Angiopatías Diabéticas/prevención & control , Femenino , Humanos , Masculino , Metaplasia , Ratones , Ratones Noqueados
12.
Curr Drug Targets ; 1(3): 247-60, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11465074

RESUMEN

Erectile dysfunction (ED) is a common problem, particularly in older men. The production of penile erection involves an interplay between autonomic nerves and locally released vasoactive mediators. Endothelin-1 (ET-1) is a peptide released from endothelium in the corpus cavernosum, which causes smooth muscle contraction. Recent studies have investigated the physiological significance of ET-1 in the control of erectile function and it may play a role in detumescence. There is also much evidence to link ET-1 to risk factors for ED. ET-1 antagonists may prove beneficial in the treatment of ED and also in prevention of long term deterioration of erectile function. These antagonists may also find a role when used in combination with agents, which are established for the treatment of ED.


Asunto(s)
Endotelina-1/antagonistas & inhibidores , Disfunción Eréctil/metabolismo , Erección Peniana/fisiología , Animales , Antihipertensivos/farmacología , Antihipertensivos/uso terapéutico , Bosentán , Complicaciones de la Diabetes , Diabetes Mellitus/metabolismo , Endotelina-1/fisiología , Disfunción Eréctil/tratamiento farmacológico , Disfunción Eréctil/etiología , Humanos , Hipercolesterolemia/complicaciones , Hipercolesterolemia/metabolismo , Hipertensión/complicaciones , Hipertensión/metabolismo , Masculino , Isquemia Miocárdica/complicaciones , Isquemia Miocárdica/metabolismo , Vías Nerviosas/efectos de los fármacos , Vías Nerviosas/metabolismo , Óxido Nítrico/fisiología , Erección Peniana/efectos de los fármacos , Factores de Riesgo , Fumar/efectos adversos , Fumar/metabolismo , Sulfonamidas/farmacología , Sulfonamidas/uso terapéutico
13.
J Med Chem ; 32(3): 688-93, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2918518

RESUMEN

A series of heterocyclic N-[(diethylamino)alkyl]arenamides related to acecainide was prepared and examined for antiarrhythmic activity. The compounds were synthesized from the corresponding known heterocyclic carboxylic acids or esters by using standard amide formation methods. The effects of the compounds on the electrophysiological properties of canine Purkinje fibers and ventricular muscle strips were determined. Most of the compounds showed effects consistent with weak class I activity. Two compounds, N-[2-(diethylamino)ethyl]-3,4,5-trimethyl-1H-pyrrole-2-carboxamide and N-[2-(diethylamino)ethyl]-1H-indole-2-carboxamide, displayed prolongation of the action potential duration and functional refractory period indicative of modest class III electrophysiological activity. Representative compounds were examined by using molecular modeling techniques. Compounds of differing activity classes displayed qualitatively different electrostatic potential maps.


Asunto(s)
Antiarrítmicos/síntesis química , Benzamidas/síntesis química , Potenciales de Acción/efectos de los fármacos , Animales , Benzamidas/farmacología , Fenómenos Químicos , Química , Perros , Electrofisiología , Técnicas In Vitro , Músculos Papilares/efectos de los fármacos , Ramos Subendocárdicos/efectos de los fármacos , Relación Estructura-Actividad
14.
J Med Chem ; 33(10): 2883-91, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1976812

RESUMEN

Several (aryloxy)propanolamines and related compounds (i.e. 5-13, 16-18, 20-24, 27-33, 35, 37-39, 41, and 42) were synthesized and investigated for their class III electrophysiological activity and class II (beta-blocking) effects with use of in vitro and in vivo models. Structure-activity relationships are discussed for a series of 30 compounds. A number of these compounds prolonged the action potential duration at 95% repolarization of isolated canine cardiac Purkinje fibers by 20% (C20APD95) at concentrations of less than 1.0 microM, with no significant effects on cardiac conduction. beta-Adrenergic receptor binding studies showed that some of these compounds were 2-20 times more potent for cardiac beta 1 receptors than for beta 2 receptors. In particular, compounds 32, 41, 1, and especially (S)-1 were found to be orally active class III agents in anesthetized mongrel dogs (1 or 3 mg/kg, id) and efficacious at suppressing programmed electrical stimulation induced arrhythmias in halothane-anesthetized dogs. The profile of these compounds was similar to that found for sotalol. Compound (S)-1, which was more potent than sotalol in the PES study and equieffective in the halothane/epinephrine dog model, is being investigated further as a combined class III/II antiarrhythmic agent.


Asunto(s)
Antagonistas Adrenérgicos beta/síntesis química , Antiarrítmicos/síntesis química , Propanolaminas/síntesis química , Potenciales de Acción/efectos de los fármacos , Antagonistas Adrenérgicos beta/metabolismo , Animales , Antiarrítmicos/metabolismo , Presión Sanguínea/efectos de los fármacos , Fenómenos Químicos , Química Física , Perros , Diseño de Fármacos , Epinefrina/antagonistas & inhibidores , Frecuencia Cardíaca/efectos de los fármacos , Técnicas In Vitro , Propanolaminas/metabolismo , Ramos Subendocárdicos/fisiología , Receptores Adrenérgicos beta/metabolismo
15.
J Med Chem ; 30(12): 2259-69, 1987 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3681896

RESUMEN

The syntheses and cardiac electrophysiological effects of 21 2- and 3-substituted quinuclidines and some quaternary ammonium derivatives are described. The 2-substituted quinuclidines 2-8 were prepared by alkylation of 2-methylene-3-quinuclidinone. The Wittig reaction with 3-quinuclidinone afforded the 3-substituted derivative 9, which was subsequently converted to 10 and 11. The electrophysiological profiles of the compounds were determined in canine cardiac Purkinje fibers and ventricular muscle strips. The 3-[(substituted phenyl)alkyl]quinuclidines selectively increased action potential duration (Vaughan Williams class III activity). In the 2-substituted series some of the compounds both increased action potential duration and decreased conduction velocity (class I activity). For some of the 2-substituted quinuclidines, appropriate substitution of the phenyl ring was shown to be a requirement for significant class III electrophysiological activity. Selected compounds were efficacious in a programmed electrical stimulation model in the anesthetized dog.


Asunto(s)
Corazón/efectos de los fármacos , Quinuclidinas/síntesis química , Potenciales de Acción/efectos de los fármacos , Animales , Antiinflamatorios/farmacología , Presión Sanguínea/efectos de los fármacos , Perros , Corazón/fisiología , Frecuencia Cardíaca/efectos de los fármacos , Técnicas In Vitro , Conformación Molecular , Quinuclidinas/farmacología , Periodo Refractario Electrofisiológico/efectos de los fármacos , Relación Estructura-Actividad
16.
J Med Chem ; 35(4): 743-50, 1992 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-1347318

RESUMEN

A series of novel arylpiperazines have been prepared in an attempt to incorporate both class II (beta-receptor blocking) and class III antiarrhythmic properties in a single molecule. The key step in the preparation of the new compounds involves a regioselective heterocyclic ring formation. All but four compounds significantly prolonged action potential duration in canine cardiac Purkinje fibers (class III activity). All but one of the compounds demonstrated beta-receptor affinity in a competitive binding assay and three had beta 1-receptor selectivity. Compared to sotalol, a reference class II/III agent, arylpiperazine 7a (4-[(methylsulfonyl)amino]-N-[(4- phenylpiperazin-2-yl)methyl]benzamide) demonstrated beta 1-selectivity and was 1 order of magnitude more potent in the in vitro class III and the beta 1-receptor screens. Compound 7a was evaluated further and found to be effective in preventing programmed electrical stimulation-induced arrhythmias in conscious dogs (class III activity) and against epinephrine-induced arrhythmias in halothane anesthetized dogs (class II activity).


Asunto(s)
Antagonistas Adrenérgicos beta/síntesis química , Antiarrítmicos/síntesis química , Benzamidas/síntesis química , Corazón/fisiología , Piperazinas/síntesis química , Potenciales de Acción/efectos de los fármacos , Antagonistas Adrenérgicos beta/farmacología , Antagonistas Adrenérgicos beta/uso terapéutico , Animales , Antiarrítmicos/farmacología , Antiarrítmicos/uso terapéutico , Arritmias Cardíacas/tratamiento farmacológico , Arritmias Cardíacas/etiología , Benzamidas/farmacología , Benzamidas/uso terapéutico , Unión Competitiva , Perros , Estimulación Eléctrica , Electrofisiología , Epinefrina , Corazón/efectos de los fármacos , Estructura Molecular , Piperazinas/farmacología , Piperazinas/uso terapéutico , Ramos Subendocárdicos/efectos de los fármacos , Ramos Subendocárdicos/fisiología , Receptores Adrenérgicos beta/metabolismo , Sotalol/farmacología , Sotalol/uso terapéutico , Relación Estructura-Actividad
17.
J Med Chem ; 33(2): 627-33, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2299628

RESUMEN

Twelve novel derivatives of the selective class III antiarrhythmic agent sematilide were prepared in an attempt to incorporate both class I and class III electrophysiological properties into a single molecule. Electrophysiological activity was determined by standard microelectrode techniques in canine cardiac Purkinje fibers. Initial assessment of class I efficacy was carried out in a ouabain-induced arrhythmia model in guinea pigs. All of the compounds prolonged action potential duration in Purkinje fibers (class III activity), and three were active against ouabain-induced arrhythmias (class I activity). Selected compounds were evaluated further in dogs for efficacy against arrhythmias occurring 24 h following coronary ligation (automatic arrhythmias) and induced by using programmed electrical stimulation techniques (reentrant arrhythmias). The most effective compounds from the series are 3g and -j, which were effective in both canine models. Molecular modeling and structure-activity relationships are discussed.


Asunto(s)
Antiarrítmicos/síntesis química , Arritmias Cardíacas/tratamiento farmacológico , Procainamida/análogos & derivados , Potenciales de Acción/efectos de los fármacos , Animales , Antiarrítmicos/clasificación , Antiarrítmicos/farmacología , Arritmias Cardíacas/inducido químicamente , Fenómenos Químicos , Química , Perros , Diseño de Fármacos , Electrofisiología , Cobayas , Técnicas In Vitro , Ouabaína , Ramos Subendocárdicos , Relación Estructura-Actividad
18.
J Med Chem ; 30(4): 696-704, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3560162

RESUMEN

Novel 3-alkyl-1-[omega-[4-[(alkylsulfonyl)amino]phenyl]-omega-hydroxyalkyl]-1H -imidazolium salts were synthesized and investigated for their class III electrophysiological activity on isolated canine cardiac Purkinje fibers and ventricular muscle tissue. Structure-activity relationships are discussed for a series of 25 compounds. Compound 3, 1-[2-hydroxy-2-[4-[(methylsulfonyl)amino]phenyl]ethyl]-3-methyl-1H- imidazolium chloride, prolonged the functional refractory period in anesthetized dogs when given intraduodenally and was also effective in preventing reentrant ventricular tachycardia induced by programmed electrical stimulation when administered intravenously in anesthetized dogs 24 h after an acute myocardial infarction. Both enantiomers of 3 were synthesized. No enantioselectivity was found in the electrophysiological effects of 3.


Asunto(s)
Antiarrítmicos , Sistema de Conducción Cardíaco/efectos de los fármacos , Corazón/efectos de los fármacos , Imidazoles/farmacología , Ramos Subendocárdicos/efectos de los fármacos , Sulfonamidas/farmacología , Animales , Antiarrítmicos/síntesis química , Antiarrítmicos/farmacología , Antiarrítmicos/uso terapéutico , Estimulación Cardíaca Artificial , Bovinos , Fenómenos Químicos , Química , Ventrículos Cardíacos , Imidazoles/síntesis química , Imidazoles/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Relación Estructura-Actividad , Sulfonamidas/síntesis química , Sulfonamidas/uso terapéutico , Taquicardia/prevención & control
19.
J Med Chem ; 30(12): 2303-9, 1987 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3681900

RESUMEN

Novel analogues of the class III antiarrhythmic agent 1-[2-hydroxy-2-[4-[(methylsulfonyl)amino]phenyl]ethyl]-3-methyl-1H- imidazolium chloride, 1 (CK-1649), were prepared and investigated for their class III electrophysiological activity on isolated canine cardiac Purkinje fibers and ventricular muscle tissue. Structure-activity relationships are discussed for a series of 11 compounds. One compound, N-[4-[1-hydroxy-2-(4,5-dihydro-2-methyl-1H-imidazol-1- yl)ethyl]phenyl]methanesulfonamide hydrochloride, 9, was comparable in activity to 1 in vitro and prolonged the functional refractory period in anesthetized dogs when given intraduodenally. Unlike 1, compound 9 was ineffective at preventing ventricular tachycardia induced by programmed electrical stimulation in anesthetized dogs 24 h after an acute myocardial infarction.


Asunto(s)
Antiarrítmicos/síntesis química , Imidazoles/síntesis química , Sulfonamidas/síntesis química , Potenciales de Acción/efectos de los fármacos , Animales , Antiarrítmicos/farmacología , Perros , Imidazoles/farmacología , Técnicas In Vitro , Ramos Subendocárdicos/efectos de los fármacos , Ramos Subendocárdicos/fisiología , Periodo Refractario Electrofisiológico/efectos de los fármacos , Relación Estructura-Actividad , Sulfonamidas/farmacología , Taquicardia/prevención & control
20.
J Med Chem ; 29(8): 1398-405, 1986 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3735308

RESUMEN

The syntheses of seven 4-(substituted phenyl)but-2-en(or yn)yl quaternary ammonium salts and four related tertiary amines are described. The Meerwein arylation reaction was the preferred synthetic method for the required intermediate 1-aryl-4-halo-2-butenes (15a-c, 18). In the case of 18, the trans stereochemistry of the Meerwein adduct of 2,3-dimethylbutadiene was established unambiguously by 2D NMR and X-ray studies. The title compounds represent conformationally restricted analogues of the class III antiarrhythmic agent clofilium (1) and exhibit comparable potency and efficacy in the in vitro evaluation using isolated canine Purkinje fibers. These results suggest that the alkylene chain in 1 is extended in the active conformation. Computer-aided conformational analysis (MM2) supports this conclusion. Selective catalytic hydrogen conditions were developed for the conversion of the unsaturated analogue 2 to clofilium (1) with minimal hydrogenolysis of the allylic quaternary ammonium moiety, thus completing a novel and efficient synthesis of this substance.


Asunto(s)
Alquenos/síntesis química , Antiarrítmicos/síntesis química , Compuestos de Amonio Cuaternario/síntesis química , Potenciales de Acción/efectos de los fármacos , Alquenos/farmacología , Animales , Disponibilidad Biológica , Presión Sanguínea/efectos de los fármacos , Perros , Electrofisiología , Frecuencia Cardíaca/efectos de los fármacos , Conformación Molecular , Ramos Subendocárdicos/efectos de los fármacos , Compuestos de Amonio Cuaternario/farmacología , Relación Estructura-Actividad
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