Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
1.
Front Pharmacol ; 15: 1394987, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38746014

RESUMEN

The pharmaceutical medicine course at the Semmelweis University of Budapest, Hungary, was initiated as part of the Innovative Medicines Initiative (IMI is the main program, IMI-PharmaTrain is one of the IMI projects) Pharmaceutical Medicine Training Programs (16 IMI Call 2008/1/16). The aim was to extend training in the development of pharmaceutical medicine to those EU member states where no such education was present. The final program envisaged the development of a cooperative education supported by universities located in Central and Eastern Europe. It was considered to be the economically and scientifically most viable approach to combine the expertise from these countries to form a united teaching staff and provide education jointly for young professionals of the region. Semmelweis University was selected to manage this coordinated program. In this report, we describe the organization and functioning of this international university-based pharmaceutical medicine education project called the Cooperative European Medicines Development Course (CEMDC) and evaluate its successes and shortcomings. During the pandemic, the educational course was interrupted. The follow-on program is reorganized as a postgraduate MSc course named "Semmelweis Pharma MBA" and will be started in 2025. It will continue the established PharmaTrain educational tradition. However, it will deal in more detail with the transition from basic pharmacological to industrial research, as well as biopharmaceutical formulation and manufacturing and marketing aspects of medicines development.

2.
Clin Transl Sci ; 9(3): 139-48, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27169903

RESUMEN

Cenicriviroc, a dual CCR2/CCR5 antagonist, is being evaluated for treatment of nonalcoholic steatohepatitis and liver fibrosis (CENTAUR; NCT02217475). As it is metabolized by the liver, cenicriviroc was investigated in hepatic-impaired participants for pharmacokinetic changes. Participants with mild-to-moderate hepatic impairment (HI) (Child-Pugh class A (N  =  7) or B (N = 8)) and matched controls (N = 15) received cenicriviroc 150 mg once daily for 14 days. Serial blood samples were obtained on Days 1 and 14. Safety, tolerability, and effects on CCR2/CCR5 ligands, cytokines, and bacterial translocation biomarkers were evaluated. Cenicriviroc exposures were increased by moderate HI (AUC0-τ  55%, Cmax 29% higher) but were not with mild HI (AUC0-τ 38%, Cmax 40% lower). Cenicriviroc was well tolerated. Rapid and potent CCR2/CCR5 blockade was observed, not associated with increases in hepatic inflammation or bacterial translocation biomarkers. Study findings suggest that cenicriviroc 150 mg can be used in patients with mild-to-moderate HI.


Asunto(s)
Imidazoles/efectos adversos , Imidazoles/farmacocinética , Hepatopatías/tratamiento farmacológico , Receptores CCR2/antagonistas & inhibidores , Receptores CCR5/metabolismo , Traslocación Bacteriana/efectos de los fármacos , Biomarcadores/metabolismo , Estudios de Casos y Controles , Citocinas/metabolismo , Demografía , Proteínas de Unión a Ácidos Grasos/metabolismo , Femenino , Flagelina/metabolismo , Humanos , Imidazoles/administración & dosificación , Imidazoles/sangre , Mediadores de Inflamación/metabolismo , Intestinos/efectos de los fármacos , Hepatopatías/patología , Masculino , Persona de Mediana Edad , Permeabilidad/efectos de los fármacos , Sulfóxidos , Factores de Tiempo
3.
Nat Mater ; 13(3): 286-92, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24531398

RESUMEN

The possibility of manipulating magnetic systems without applied magnetic fields have attracted growing attention over the past fifteen years. The low-power manipulation of the magnetization, preferably at ultrashort timescales, has become a fundamental challenge with implications for future magnetic information memory and storage technologies. Here we explore the optical manipulation of the magnetization in engineered magnetic materials. We demonstrate that all-optical helicity-dependent switching (AO-HDS) can be observed not only in selected rare earth-transition metal (RE-TM) alloy films but also in a much broader variety of materials, including RE-TM alloys, multilayers and heterostructures. We further show that RE-free Co-Ir-based synthetic ferrimagnetic heterostructures designed to mimic the magnetic properties of RE-TM alloys also exhibit AO-HDS. These results challenge present theories of AO-HDS and provide a pathway to engineering materials for future applications based on all-optical control of magnetic order.

4.
Gesundheitswesen ; 76(3): 151-9, 2014 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-23780859

RESUMEN

OBJECTIVES: The aim of this study is to develop, implement and evaluate an education programme enabling the pedagogic staff of employment promotion agencies to integrate health promotion approaches und activities in vocational training programmes. METHODS: The evaluation of the education programme is based on Kirkpatrick's 4 levels training evaluation model. Besides the participants' verbal end of session feedback, a standardised questionnaire was used at the end of the education programme and after 3 months practical experience. Process evaluation included the implementation level of the methods learned. RESULTS: From a total of 71 participants, 56 completed the first and 31 the second questionnaire (return rate 79% and 44%, respectively). The participants' mean age was 42 years, 80% were female. Only 22% of them integrated health topics systematically into their daily work. A 3-day basic training followed by case conferences during practical work was developed to transfer knowledge and practical competence in person-to-person talks and group activities (so called FIT-counselling and FIT-group). For 96% of participants, their expectations regarding the education programme were met completely or predominantly. 91% indicated a rise in motivation to work as health coach. When rating the training material, 96% judged it helpful for implementation/transfer. Many participants marked the education programme as being too short and wished more time for the topic of "mental health" and exchange of experiences. The follow-up after 3 months on-the-job training revealed that 84 and 97%, respectively, found FIT-counselling and FIT-groups helpful for their daily work. In all employment promotion agencies FIT-counselling and FIT-groups were implemented. CONCLUSION: Our results affirm the need for and prove the acceptance of education programmes enabling the pedagogic staff of job-training programmes to deliver health coaching. Periodic case conferences take into account the participants' request for more exchange of experiences, facilitate implementation and contribute to quality and sustainability. Further development of the education programme is ongoing.


Asunto(s)
Empleo/organización & administración , Educación en Salud/organización & administración , Promoción de la Salud/organización & administración , Modelos Organizacionales , Educación Vocacional/organización & administración , Adulto , Evaluación Educacional , Femenino , Alemania , Humanos , Masculino , Mercadotecnía/organización & administración , Mentores , Evaluación de Programas y Proyectos de Salud
5.
Ultrasound Med Biol ; 39(5): 834-44, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23465134

RESUMEN

High-frequency ultrasound (US) surface parameters are well known to be sensitive to degenerative changes in cartilage tissue, but estimates deteriorate if the sample is inclined. We propose 3-D US to precisely estimate the local surface and inclination. For this purpose, the most common ultrasonic surface parameters ultrasound roughness index and integrated reflection coefficient were extended to 2-D surface measurements. Tissue-mimicking phantoms and human cartilage samples with varying degrees of degeneration were measured using a 40-MHz transducer. Characteristic inclination dependencies of the parameters aided in the distinction between specular reflected or backscattered signal origins and allowed a restriction to suitable local inclinations. In the application to cartilage, comparisons with histologic grading (structural Mankin-score) depicted a statistically significant (p < 0.05) increase of US roughness index for scores larger than 0 and decrease of integrated reflection coefficient for scores larger than 1. The presented findings will increase the reliability of ultrasonic surface parameters and can in principal be applied in vivo.


Asunto(s)
Algoritmos , Cartílago Articular/diagnóstico por imagen , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Osteoartritis/diagnóstico por imagen , Ultrasonografía/métodos , Humanos , Fantasmas de Imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Propiedades de Superficie , Ultrasonografía/instrumentación
6.
Unfallchirurg ; 109(9): 743-53, 2006 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-16897028

RESUMEN

Spondylodiscitis is a rare bacterial infection of the spine with an inflammatory, destructive course. To obtain further information on the therapeutic management and clinical course of spondylodiscitis, we retrospectively investigated 78 patients after surgical intervention. Mean age was 64 years (+/-4.6 years; range 21-80 years), the mean length of stay 49 days (+/-8.2 days; 3-121 days) including 24 days (+/-4.7 days; 0-112 days) in ICU. In hospital mortality was 9%. The cervical spine was affected in 10%, the thoracic spine in 35% and the lumbar/sacral spine in 55% of patients. Abscess formation occurred in 65% and destruction of the vertebral body in 74%. A total of 75% of patients presented with neurological deficits which could be improved by surgical intervention in 82% of cases. 24 patients were treated by ventral debridement and stabilization alone, 20 patients with a combined dorsoventral method. Most patients (n=34) were stabilized via dorsal bridging instrumentation without ventral debridement of the focus. Of this group, 23 patients were initially scheduled for secondary ventral debridement but complete healing was achieved prior to this, so further surgical therapy was unnecessary. Successful cure was obtained in 92% of cases. Based on our findings, we favor a split surgical approach: initially with dorsal internal fixation only. Abscesses can be drained percutaneously. Ventral debridement and stabilization is only recommended if insufficient stability can be obtained by dorsal fixation alone, as shown by the persistence of infection or pain.


Asunto(s)
Vértebras Cervicales , Discitis/cirugía , Vértebras Lumbares , Sacro , Vértebras Torácicas , Adulto , Anciano , Anciano de 80 o más Años , Desbridamiento , Discitis/diagnóstico , Drenaje , Femenino , Humanos , Tiempo de Internación , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos , Fusión Vertebral , Resultado del Tratamiento
7.
Zentralbl Chir ; 128(4): 337-40, 2003 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-12700994

RESUMEN

Anastomotic leakage is a serious complication in abdominal surgery. We report on two cases of spondylodiscitis L5/S1 following anastomotic leakage with fistula after low anterior rectal resection. Within five months after rectal resection two patients with massive back pain were admitted to our department. MRI established the diagnosis of spondylodiscitis. Ventral debridement, spondylodesis and protective stoma were performed. With this procedure we were able to achieve control of infection. There were no further complications in the follow-up. Stability of the spinal column was restored and massive back pain was entirely relieved. No signs of rectal cancer recurrence were seen in both cases during the observation period.


Asunto(s)
Anastomosis Quirúrgica , Discitis/etiología , Ileostomía , Vértebras Lumbares , Neoplasias del Recto/cirugía , Recto/cirugía , Sacro , Dehiscencia de la Herida Operatoria/complicaciones , Colostomía , Discitis/diagnóstico , Discitis/cirugía , Estudios de Seguimiento , Humanos , Vértebras Lumbares/patología , Vértebras Lumbares/cirugía , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recto/patología , Reoperación , Estudios Retrospectivos , Sacro/patología , Sacro/cirugía , Fusión Vertebral , Dehiscencia de la Herida Operatoria/diagnóstico , Dehiscencia de la Herida Operatoria/cirugía
8.
N Engl J Med ; 345(9): 631-7, 2001 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-11547716

RESUMEN

BACKGROUND: It is uncertain whether the administration of benzodiazepines by paramedics is an effective and safe treatment for out-of-hospital status epilepticus. METHODS: We conducted a randomized, double-blind trial to evaluate intravenous benzodiazepines administered by paramedics for the treatment of out-of-hospital status epilepticus. Adults with prolonged (lasting five minutes or more) or repetitive generalized convulsive seizures received intravenous diazepam (5 mg), lorazepam (2 mg), or placebo. An identical second injection was given if needed. RESULTS: Of the 205 patients enrolled, 66 received lorazepam, 68 received diazepam, and 71 received placebo. Status epilepticus had been terminated on arrival at the emergency department in more patients treated with lorazepam (59.1 percent) or diazepam (42.6 percent) than patients given placebo (21.1 percent) (P=0.001). After adjustment for covariates, the odds ratio for termination of status epilepticus by the time of arrival in the lorazepam group as compared with the placebo group was 4.8 (95 percent confidence interval, 1.9 to 13.0). The odds ratio was 1.9 (95 percent confidence interval, 0.8 to 4.4) in the lorazepam group as compared with the diazepam group and 2.3 (95 percent confidence interval, 1.0 to 5.9) in the diazepam group as compared with the placebo group. The rates of respiratory or circulatory complications (indicated by bag valve-mask ventilation or an attempt at intubation, hypotension, or cardiac dysrhythmia) after the study treatment was administered were 10.6 percent for the lorazepam group, 10.3 percent for the diazepam group, and 22.5 percent for the placebo group (P=0.08). CONCLUSIONS: Benzodiazepines are safe and effective when administered by paramedics for out-of-hospital status epilepticus in adults. Lorazepam is likely to be a better therapy than diazepam.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Diazepam/uso terapéutico , Servicios Médicos de Urgencia , Lorazepam/uso terapéutico , Estado Epiléptico/tratamiento farmacológico , Adulto , Anticonvulsivantes/efectos adversos , Diazepam/efectos adversos , Método Doble Ciego , Auxiliares de Urgencia , Femenino , Humanos , Inyecciones Intravenosas , Modelos Logísticos , Lorazepam/efectos adversos , Masculino , Persona de Mediana Edad , Estado Epiléptico/mortalidad
10.
Control Clin Trials ; 22(3): 290-309, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11384791

RESUMEN

Status epilepticus is a neurological emergency that is typically first encountered and managed in the prehospital environment. Although aggressive pharmacological treatment of status epilepticus is well established in the emergency department and hospital settings, the relative risks and benefits of active therapy for status epilepticus in the prehospital setting are not known. The Prehospital Treatment of Status Epilepticus (PHTSE) study is a prospective, randomized, double-blind, placebo-controlled study designed to address the following aims: (1) to determine whether administration of benzodiazepines by paramedics is an effective and safe means of treating status epilepticus in the prehospital setting and whether this therapy influences longer-term patient outcome, (2) to determine whether lorazepam is superior to diazepam for the treatment of status epilepticus in the prehospital setting, and (3) to determine whether control of status epilepticus prior to arrival to the emergency department influences patient disposition. The initial phase of the PHTSE study began in January 1994 and was completed in February 1999 after the successful enrollment of 205 patients into the three treatment arms. In this paper, we describe the rationale for the conceptualization of the study and details of the study design and methodology, and emphasize some aspects of study implementation that are unique to research involving the emergency medical system.


Asunto(s)
Benzodiazepinas/uso terapéutico , Servicios Médicos de Urgencia , Estado Epiléptico/tratamiento farmacológico , Adulto , Algoritmos , Método Doble Ciego , Humanos , Modelos Logísticos , Tamaño de la Muestra , San Francisco
11.
Cell Commun Adhes ; 8(4-6): 257-64, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-12064599

RESUMEN

We investigated the effects of the antiarrhythmic peptide AAP10 (GAG-4Hyp-PY-CONH2, 50 nM) on pairs of adult guinea pig cardiomyocytes and on pairs of HeLa-cells transfected with rat connexin43 (Cx43). Using double cell voltage clamp technique in cardiomyocytes under control conditions, gap junction conductance (Gj) steadily decreased (by -0.3 to -0.4 nS/min). In contrast, 50 nM AAP10 significantly enhanced Gj (by +0.22 to +0.29 nS/min). This effect of AAP10 could be significantly antagonized by bisindolylmaleimide I (BIM), and by the protein kinase C (PKC) subtype-specific inhibitors HBDDE (PKCgamma and -alpha) and CGP 54345 (PKCalpha). In HeLa-Cx43 cells we found similar electrophysiological effects of AAP10. For further analysis, we incubated HeLa-Cx43 cells with [32P]orthophosphate (0.05 mCi/ml) for 4 h at 37 degrees C followed by addition of 50 nM AAP10 for 15 min. We found that incorporation of 32P into Cx43 was significantly enhanced in the presence of AAP10, which was completely inhibited in presence of BIM. PKC enzyme-linked immunosorbent assay (ELISA) revealed significant activation of PKC by AAP10 in HeLa-Cx43 cells, which could be inhibited by HBDDE and CGP 54345. Finally, a binding study using [14C]-AAP10 as radioligand was performed. We found a saturable binding of [14C]-AAP10 with a KD of 0.88 nM to cardiac membrane preparations. For assessment of the antiarrhythmic activity in anesthetized rats, we infused aconitine until the occurrence of ventricular fibrillation (VF). The aconitine dose required for initiation of VF was significantly enhanced in the presence of AAP10. In conclusion; AAP10 increases Gj in both adult cardiomyocytes and transfected HeLa-Cx43 cells. AAP10 leads to enhanced phosphorylation of Cx43 via activation of PKCalpha. A membrane receptor exists for antiarrhythmic peptides.


Asunto(s)
Antiarrítmicos/farmacología , Uniones Comunicantes/metabolismo , Isoenzimas/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Oligopéptidos/farmacología , Proteína Quinasa C/metabolismo , Aconitina/farmacología , Animales , Conexina 43/genética , Conexina 43/metabolismo , Reactivos de Enlaces Cruzados/metabolismo , Inhibidores Enzimáticos/farmacología , Guanosina Difosfato/análogos & derivados , Cobayas , Células HeLa , Humanos , Isoenzimas/antagonistas & inhibidores , Miocitos Cardíacos/metabolismo , Técnicas de Placa-Clamp , Unión Proteica , Proteína Quinasa C/antagonistas & inhibidores , Proteína Quinasa C-alfa , Conejos , Ensayo de Unión Radioligante , Ratas
12.
Am J Health Syst Pharm ; 57(10): 953-62, 2000 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-10832495

RESUMEN

The impact of Parkinson's disease (PD) and its pharmacologic treatment on health-related quality of life (HRQL) and economic outcomes is reviewed. PD is a chronic and progressive neurologic disorder characterized by specific motor deficits resulting from the degeneration of dopaminergic neurons in the substantia nigra. The cardinal symptoms are tremor, rigidity, bradykinesia, and loss of postural reflexes. PD markedly reduces HRQL and places an economic burden on society of up to $25 billion per year. Patients' inability to move freely and to perform everyday tasks restricts their independence and leads to increased reliance on caregivers and assistive devices. Emotional and psychosocial well-being is also negatively affected. As the disease progresses, the response to levodopa typically decreases and various motor complications develop; these are difficult to treat and result in further declines in HRQL. The economic costs of PD include both direct health care costs (for drugs, physician services, and hospitalization) and indirect costs (for lost worker productivity). Economic analyses of PD and its treatments can help guide effective allocation of health care resources. Various antiparkinsonian agents and formulations, such as extended-release levodopa-carbidopa and pramipexole, have been found to be cost-effective relative to other agents. The newest antiparkinsonian drugs, cathechol-O-methyltransferase inhibitors, also have the potential to improve HRQL and economic outcomes, although more study is needed to confirm this. The total impact of PD and its treatment can be fully appreciated only when HRQL and economic outcomes, in addition to clinical outcomes, are examined.


Asunto(s)
Antiparkinsonianos/uso terapéutico , Enfermedad de Parkinson/tratamiento farmacológico , Antiparkinsonianos/economía , Costos de los Medicamentos , Humanos , Enfermedad de Parkinson/economía , Enfermedad de Parkinson/psicología , Calidad de Vida
13.
Pharmacotherapy ; 19(11 Pt 2): 162S-8S, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10555944

RESUMEN

For over 30 years, levodopa has been the gold standard for managing the symptoms of Parkinson's disease. Treatment with levodopa has resulted in a marked decrease in disease-associated mortality and morbidity. However, one of its drawbacks is that many patients experience a shorter duration of response and increased motor fluctuations with disease progression and long-term levodopa therapy. These increased motor fluctuations, including dyskinesias, may be the consequence of oxidative stress or inability to store and regulate intrasynaptic dopamine concentrations with disease progression. Clinical investigations have demonstrated that continuous dopaminergic stimulation may widen the therapeutic window for levodopa and improve motor fluctuations. Strategies for providing continuous dopaminergic replacement include administration of levodopa by continuous infusion, controlled-release levodopa, long-acting dopamine agonists, and inhibitors of levodopa metabolism. The catechol-O-methyltransferase inhibitors that block a compensatory metabolic pathway for levodopa and prolong its duration may improve the consistency of the dopaminergic response.


Asunto(s)
Antiparkinsonianos/uso terapéutico , Levodopa/uso terapéutico , Enfermedad de Parkinson/tratamiento farmacológico , Antiparkinsonianos/efectos adversos , Inhibidores de Catecol O-Metiltransferasa , Progresión de la Enfermedad , Agonistas de Dopamina/uso terapéutico , Discinesia Inducida por Medicamentos/tratamiento farmacológico , Discinesia Inducida por Medicamentos/prevención & control , Discinesias/metabolismo , Discinesias/patología , Discinesias/fisiopatología , Humanos , Levodopa/efectos adversos , Oportunidad Relativa , Enfermedad de Parkinson/patología
14.
Am J Emerg Med ; 17(4): 333-7, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10452426

RESUMEN

Injectable benzodiazepines are commonly stocked on ambulances for use by paramedics. We evaluated the stability of lorazepam and diazepam as a function of storage temperature. Diazepam (5 mg/mL) and lorazepam (2 mg/mL) injectable solutions were stored for up to 210 days in clear glass syringes at three conditions: 4 degrees C to 10 degrees C (refrigerated); 15 degrees C to 30 degrees C (on-ambulance ambient temperature); and 37 degrees C (oven-heated). High-performance liquid chromatography (HPLC) analyses of syringe contents were performed at 30-day intervals. After 210 days, the reduction in diazepam concentration was 7% refrigerated, 15% at ambient temperature, and 25% at 37 degrees C. The reduction in lorazepam concentration was 0% refrigerated, 10% at ambient temperature, and 75% at 37 degrees C. Whereas diazepam retained 90% of its original concentration for 30 days of on-ambulance storage, lorazepam retained 90% of its original concentration for 150 days. The decrease in lorazepam concentration correlated with an increase in the maximum ambient temperature in San Francisco. These results suggest that diazepam and lorazepam can be stored on ambulances. When ambient storage temperatures are 30 degrees C or less, ambulances carrying lorazepam and diazepam should be restocked every 30 to 60 days. When drug storage temperatures exceed 30 degrees C, more frequent stocking or refrigeration is required.


Asunto(s)
Ambulancias , Ansiolíticos/química , Diazepam/química , Lorazepam/química , Ansiolíticos/análisis , Cromatografía Líquida de Alta Presión , Frío , Diazepam/análisis , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Vidrio , Calor , Humanos , Estudios Longitudinales , Lorazepam/análisis , San Francisco , Jeringas , Temperatura , Factores de Tiempo
15.
Epilepsia ; 40(6): 777-82, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10368078

RESUMEN

PURPOSE: The pharmacokinetic behavior of fosphenytoin (FOS), the water-soluble prodrug of phenytoin (PHT), has been characterized in normal subjects. This is the first study of the effect of hepatic or renal disease on the rate and extent of conversion of FOS to PHT. METHODS: A single dose of fosphenytoin (250 mg over a period of 30 min) was administered to subjects with hepatic cirrhosis (n = 4), renal disease requiring maintenance hemodialysis (n = 4), and healthy controls (n = 4). Serial plasma concentrations were measured, and pharmacokinetic parameters were calculated. RESULTS: The mean time to reach the peak plasma FOS concentration was similar for each of the three groups. However, the mean time to achieve peak plasma concentrations of PHT tended to occur earlier in the hepatic or renal disease groups than in healthy subjects. The half-life of FOS was 4.5, 9.2, and 9.5 min for the three groups, respectively. There was a trend toward increased FOS clearance and earlier peak PHT concentration in subjects with hepatic or renal disease. This finding is consistent with decreased binding of FOS to plasma proteins and increased fraction of unbound FOS resulting from decreased plasma protein concentrations associated with these disease states. The conversion of FOS to PHT was equally efficient in subjects with hepatic or renal disease and healthy subjects. CONCLUSIONS: Although the differences in pharmacokinetic parameters between the three groups were not statistically significant, these data suggest the need for close clinical monitoring during FOS administration to patients with hepatic or renal disease. To minimize the incidence of adverse effects in this patient population, FOS may need to be administered at lower doses or infused more slowly.


Asunto(s)
Fallo Renal Crónico/metabolismo , Cirrosis Hepática/metabolismo , Fenitoína/análogos & derivados , Profármacos/farmacocinética , Adulto , Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/farmacocinética , Cromatografía Líquida de Alta Presión , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Fenitoína/administración & dosificación , Fenitoína/farmacocinética , Profármacos/administración & dosificación
16.
Expert Opin Investig Drugs ; 8(4): 453-62, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15992091

RESUMEN

Levodopa, a dopamine precursor administered with a decarboxylase inhibitor, is the principal therapy for treating the symptoms of Parkinson's disease. Unfortunately, after approximately 2-5 years, it frequently loses its beneficial effects as evidenced by motor fluctuations. Entacapone (Comtan) is a selective, reversible catechol-O-methyltransferase inhibitor that dose-dependently increases the peripheral bioavailability of levodopa and prolongs its duration of action. Early studies confirmed that treatment with entacapone resulted in increased striatal uptake of levodopa after iv. administration of [18F] levodopa. Preclinical studies confirmed decreased formation of COMT-dependent metabolites, including 3-O methyldopa and homovanillic acid. Clinical studies performed in patients with motor fluctuations have shown that entacapone prolonged the duration of motor response by an average of 1-1.3 h. Parkinsonian patients receiving therapeutic doses of dopamine agonists and selegiline also experienced an incremental improvement in 'on' time when entacapone was added to their drug regimen. At present, there are no published safety studies beyond six to twelve months in duration, or studies in nonfluctuating patients. Based on the clinical trial data available, entacapone is well-tolerated in the majority of patients. Dopaminergic-related adverse effects include dyskinesias, nausea and dizziness. Non-dopaminergic adverse effects include diarrhoea, abdominal discomfort and discoloration of urine. Diarrhoea is occasionally severe and may require discontinuation of therapy. Of 406 entacapone-treated subjects, there was one incidence of elevated liver transaminases, although this was attributed to an underlying disorder. In the US, Phase III trials have been completed and a New Drug Application (NDA) has been filed. In Europe, the drug received a favourable review and is currently available.

17.
Naunyn Schmiedebergs Arch Pharmacol ; 357(6): 662-70, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9686943

RESUMEN

Ischemia leads to intracellular acidification which can be counteracted by the Na+/H+-exchange mechanism. A blockade of this exchanger has been hypothesized to cause stronger intracellular acidification in the course of ischemia thereby protecting the heart from ischemic damage. The aim of our study was to find out (1) whether in the course of ischemia areas become electrically silent, (2) whether this is enhanced by the Na+/H+-exchange inhibitor cariporide (4-Isopropyl-3-methylsulfonylbenzoyl-guanidine; Hoe 642) and whether cariporide has protective effects. Therefore, we submitted isolated rabbit hearts, perfused according to the Langendorff technique to regional ischemia (LAD occlusion) for 30 min followed by 30 min reperfusion with (n=7) or without (n=7) pre-treatment with 1 microM cariporide. Under these conditions 256-channel epicardial potential mapping was carried out. Under non-ischemic conditions cariporide did not alter any of the parameters under observation. We found that ischemia led to marked alterations of the activation pattern, to action potential shortening and a marked increase in the dispersion of refractoriness. In the ischemic region there was a significant ST deviation from the isoelectrical line (control 32+/-10; 30 min ischemia: 290+/-35 arbitrary units [a.u.]). This was markedly reduced by cariporide (control 39+/-10; 30 min ischemia: 170+/-25 a.u.). The increase in dispersion by ischemia (by 50+/-5 ms) was significantly counteracted by cariporide (increased dispersion by 20+/-4 ms). In a similar way the alteration of the activation pattern was antagonized. Under the influence of cariporide we found a lower increase in the left ventricular enddiastolic pressure, and a significantly slower recovery of the action potential duration. After 30 min of ischemia 24+/-5 (control series) 24.5+/-5 mm2 (cariporide) became electrically silent. In a second series of experiments the incidence of arrhythmia was assessed: we found ventricular fibrillation in 6/7 untreated control hearts and in 4/7 cariporide treated hearts. In a third series of experiments we determined the intracellular [ATP] after 30 min of LAD occlusion using a histochemical method. We observed a decrease in [ATP] in the ischemic region as compared to the non-ischemic right ventricular wall, which was less pronounced in cariporide-treated hearts. Thus, we conclude that (1) cariporide protects the heart from ischemic damage and (2) at least under these conditions an enlargement of the electrically silent area did not occur.


Asunto(s)
Antiarrítmicos/farmacología , Inhibidores Enzimáticos/farmacología , Guanidinas/farmacología , Corazón/efectos de los fármacos , Intercambiadores de Sodio-Hidrógeno/antagonistas & inhibidores , Sulfonas/farmacología , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Animales , Presión Sanguínea/efectos de los fármacos , Electrocardiografía/efectos de los fármacos , Electrofisiología , Frecuencia Cardíaca/efectos de los fármacos , Técnicas In Vitro , Mediciones Luminiscentes , Masculino , Daño por Reperfusión Miocárdica/fisiopatología , Miocardio/citología , Músculos Papilares/efectos de los fármacos , Músculos Papilares/fisiología , Pericardio/citología , Pericardio/efectos de los fármacos , Conejos
18.
Heart ; 79(5): 474-80, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9659194

RESUMEN

OBJECTIVE: To examine how epicardial activation and repolarisation patterns change in the course of ischaemia, and how these changes are related to the underlying histological structures. METHODS: Langendorff perfused isolated rabbit hearts were submitted to 30 minutes of left anterior descending coronary artery occlusion followed by 30 minutes of reperfusion. A 256 channel epicardial map was plotted during the various experimental phases. Activation time points were determined as t(dU/dtmin) and repolarisation time points as t(dU/dtmax). From these data the local activation-recovery interval (ARI), its dispersion (SD of ARI), and the geometry of the activation spread could be analysed. After the experiments the hearts were processed histologically and the mapping data were projected onto histological slides. RESULTS: There was elevation of the ST segment within the occluded area, which recovered during reperfusion. Within this area, ARI was significantly shortened and its dispersion was maximally enhanced. The enhancement of dispersion was pronounced at sites of histological inhomogeneity like fat, connective tissue, or vessels. There was also a change in the preferential direction of activation spread within the occluded zone with a marked transverse propagation of the activation wave-front, whereas under normal conditions the activation followed the longitudinal fibre axis. In addition, the total activation time in the occluded area was significantly prolonged. CONCLUSIONS: Ischaemia alters the local activation pattern with enhanced dispersion, especially at sites of histological irregularity, transverse shift of the activation waves, and a general slowing of conduction, which may explain the increased susceptibility to arrhythmia in hearts with enhanced histological irregularities--for example, an infarct or in multi-infarcted hearts, or after myocarditis.


Asunto(s)
Isquemia Miocárdica/fisiopatología , Pericardio/fisiopatología , Animales , Electrocardiografía , Masculino , Isquemia Miocárdica/patología , Reperfusión Miocárdica , Perfusión , Pericardio/patología , Conejos
19.
Ann Pharmacother ; 31(10): 1205-17, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9337447

RESUMEN

OBJECTIVE: To summarize the development, pharmacology, pharmacokinetics, efficacy, and safety of five investigational antiparkinsonian drugs that are in or have recently completed Phase III trials: three dopamine agonists, pramipexole, ropinirole, and cabergoline; and two catechol-O-methyltransferase (COMT) inhibitors, entacapone and tolcapone. The pathophysiology and the role of dopamine in Parkinson's disease are also reviewed. DATA SOURCES: A MEDLINE search of relevant English-language literature, clinical studies, abstracts, and review articles pertaining to Parkinson's disease was conducted. Manual searches of 1996/1997 meeting abstracts published by the American Academy of Neurology and the Movement Disorders Society were also performed. Manufacturers provided unpublished Phase III trial efficacy and pharmacokinetic data. STUDY SELECTION AND DATA EXTRACTION: Clinical trial investigations selected for inclusion were limited to human subjects. Interim analyses after 6 months for long-term clinical studies in progress were included. Pharmacokinetic data from animals were cited if human data were unavailable. Statistical analyses for all studies were evaluated. DATA SYNTHESIS: By selectivity targeting D2 receptors, the newer dopamine agonists (i.e., cabergoline, pramipexole, ropinirole) may delay the introduction of levodopa and thus the occurrence of levodopa-induced dyskinesias. In addition, they are efficacious as adjunctive therapies in patients with advanced Parkinson's disease. Unlike the currently available dopamine agonists, pramipexole and ropinirole are non-ergot derivatives and do not cause skin inflammation, paresthesias, pulmonary infiltrates, or pleural effusion. The COMT inhibitors, tolcapone and entacapone, improve the pharmacokinetics of levodopa by preventing its peripheral catabolism and increasing the concentration of brain dopamine; thus, these agents may reduce the incidence of "wearing-off" effects associated with the short half-life of levodopa and the progression of Parkinson's disease. CONCLUSIONS: Interim 6-month analyses of pramipexole, ropinirole, and cabergoline for symptomatic treatment of early Parkinson's disease have shown these drugs to be efficacious and relatively well-tolerated when used as monotherapy. Their role in delaying the development of motor fluctuations and delaying the addition of levodopa is the subject of long-term clinical studies. In advanced stages of Parkinson's disease, these medications were also efficacious; however, the main adverse effects included dyskinesias, somnolence, and hallucinations. The COMT inhibitors, entacapone and tolcapone, have also demonstrated efficacy in improving on-time in patients with stable disease. Tolcapone has also demonstrated efficacy in patients with motor fluctuations. Both drugs are relatively well-tolerated, with the exception of dyskinesias that require reduction of the levodopa dosage and occasional diarrhea.


Asunto(s)
Inhibidores de Catecol O-Metiltransferasa , Agonistas de Dopamina/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Enfermedad de Parkinson/tratamiento farmacológico , Benzofenonas/farmacocinética , Benzofenonas/farmacología , Benzofenonas/uso terapéutico , Benzotiazoles , Cabergolina , Catecoles/farmacocinética , Catecoles/farmacología , Catecoles/uso terapéutico , Agonistas de Dopamina/farmacocinética , Agonistas de Dopamina/farmacología , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/farmacología , Ergolinas/farmacocinética , Ergolinas/farmacología , Ergolinas/uso terapéutico , Humanos , Indoles/farmacocinética , Indoles/farmacología , Indoles/uso terapéutico , Nitrilos , Nitrofenoles , Enfermedad de Parkinson/fisiopatología , Pramipexol , Receptores de Dopamina D2/efectos de los fármacos , Receptores de Dopamina D2/fisiología , Tiazoles/farmacocinética , Tiazoles/farmacología , Tiazoles/uso terapéutico , Tolcapona
20.
Naunyn Schmiedebergs Arch Pharmacol ; 356(1): 76-82, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9228193

RESUMEN

Disturbances in gap junction distribution and a decrease in the connexin43 content of the heart were shown to occur after myocardial infarction and in ischemic heart disease, respectively. These changes are now thought to play an important role in the genesis of arrhythmias associated with these diseases. It is thought that agents that can increase cellular coupling might be beneficial in these situations. Recently, we presented data showing that the synthetic peptide AAP10 acts antiarrhythmically in a model of regional ischemia. The data suggested that AAP10 might act via an increase in cellular coupling. The goal of this study was to establish whether AAP10 can interact with cardiac gap junctions. Measurements of the stimulus-response-interval (SRI) in guinea pig papillary muscle showed that high concentrations of AAP10 (1 microM) can decrease the SRI by about 10% under normoxic conditions. At lower concentrations (10 nM) AAP10 had no effect on SRI under normoxic conditions but prevented the increase in the SRI induced by perfusion with hypoxic, glucose-free Tyrode's solution. Double-cell voltage-clamp experiments confirmed that AAP10 can interact with cardiac gap junctions. 10 nM AAP10 could either diminish or reverse the run-down of gap junction conductance normally observed in pairs of guinea pig ventricular myocytes. During control gap junction conductance decreased with a rate of -2.5 +/- 2.0 nS/min. After application of 10 nM AAP10 gap junction conductance increased with a rate of +1.0 +/- 0.7 nS/min (p < 0.01). After washout of AAP10 gap junction conductance decreased again with a rate not significantly different from control. Our results show that AAP10 does interact with gap junctions. Because no other effects of AAP10 on other electrophysiological parameters could be found, this action on gap junctions might be the basis of AAP10's antiarrhythmic effect seen in previous studies.


Asunto(s)
Antiarrítmicos/farmacología , Uniones Comunicantes/efectos de los fármacos , Oligopéptidos/farmacología , Potenciales de Acción/efectos de los fármacos , Animales , Cobayas , Técnicas In Vitro , Masculino , Isquemia Miocárdica/fisiopatología , Músculos Papilares/efectos de los fármacos , Técnicas de Placa-Clamp , Tiempo de Reacción/efectos de los fármacos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA