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1.
Rev Neurol (Paris) ; 180(6): 539-547, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38102053

RESUMEN

INTRODUCTION: Patent foramen ovale (PFO) is present in a significant proportion of young patients with stroke of undetermined etiology, but is not always causal. Therefore, classifications (RoPE, PASCAL) have been developed to determine the probability that PFO is the stroke cause. However, the presence of an initial arterial occlusion as a prediction factor was not studied when these classifications were built. Our aim was to evaluate the presence of arterial occlusion in young patients with stroke of undetermined etiology with/without high-risk PFO. METHODS: From a prospectively-built monocentric database, we identified patients aged≥18 to<60-years with strokes of undetermined etiology and complete etiological work-up, including transesophageal echocardiography. We divided patients in two groups: (i) with high-risk PFO [i.e. PFO with large interatrial shunt (>30 microbubbles) or associated with atrial septal aneurysm] and (ii) with low-risk/without PFO. We recorded the presence of arterial occlusion and large vessel occlusion (LVO) in the acute phase. RESULTS: We included 96 patients; 55 (57%) had high-risk PFO. Their median age was 48 (40-52) years, and 28 (29%) were women. The percentages of patients with arterial occlusion and with LVO were lower in the high-risk PFO group than in the low-risk/without PFO group: 11 (20%) versus 19 (46%) (P=0.008), and 5 (9%) versus 15 (37%) (P=0.002), respectively. There was no difference in the median RoPE score between groups (P=0.30). CONCLUSION: The presence of LVO could represent a "red flag" of PFO causality in stroke of undetermined etiology, and could be implemented in future PFO-related stroke classifications.


Asunto(s)
Foramen Oval Permeable , Accidente Cerebrovascular , Humanos , Foramen Oval Permeable/complicaciones , Foramen Oval Permeable/epidemiología , Foramen Oval Permeable/diagnóstico por imagen , Femenino , Masculino , Adulto , Persona de Mediana Edad , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Factores de Riesgo , Estudios Prospectivos , Adulto Joven , Ecocardiografía Transesofágica , Adolescente , Arteriopatías Oclusivas/etiología , Arteriopatías Oclusivas/epidemiología , Arteriopatías Oclusivas/complicaciones
2.
Rev Neurol (Paris) ; 178(6): 558-568, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34903351

RESUMEN

BACKGROUND AND PURPOSE: The best transportation strategy for patients with suspected large vessel occlusion (LVO) is unknown. Here, we evaluated a new regional strategy of direct transportation to a Comprehensive Stroke Center (CSC) for patients with suspected LVO and low probability of receiving intravenous thrombolysis (IVT) at the nearest Primary Stroke Center (PSC). METHODS: Patients could be directly transported to the CSC (bypass group) if they met our pre-hospital bypass criteria: high LVO probability (i.e., severe hemiplegia) with low IVT probability (contraindications) and/or travel time difference between CSC and PSC<15 minutes. The other patients were transported to the PSC according to a "drip-and-ship" strategy. Treatment time metrics were compared in patients with pre-hospital bypass criteria and confirmed LVO in the bypass and drip-and-ship groups. RESULTS: In the bypass group (n=79), 54/79 (68.3%) patients met the bypass criteria and 29 (36.7%) had confirmed LVO. The positive predictive value of the hemiplegia criterion for LVO detection was 0.49. In the drip-and-ship group (n=457), 92/457 (20.1%) patients with confirmed LVO met our bypass criteria. Among the 121 patients with bypass criteria and confirmed LVO, direct routing decreased the time between symptom discovery and groin puncture by 55 minutes compared with the drip-and-ship strategy (325 vs. 229 minutes, P<0.001), without significantly increasing the time to IVT (P=0.19). CONCLUSIONS: Our regional strategy led to the correct identification of LVO and a significant decrease of the time to mechanical thrombectomy, without increasing the time to IVT, and could be easily implemented in other territories.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/tratamiento farmacológico , Hemiplejía , Humanos , Probabilidad , Estudios Retrospectivos , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/tratamiento farmacológico , Trombectomía , Terapia Trombolítica , Resultado del Tratamiento
5.
Int J Immunopathol Pharmacol ; 19(4): 919-22, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17166413

RESUMEN

We report the case of a perinatally HIV-1-infected child, previously immunologically unresponsive to antiretroviral treatments (including the highly active antiretroviral therapy), who instead developed a vigorous and long-lasting immune response after the highly active antiretroviral therapy was associated with antineoplastic chemotherapy undertaken for a B-cell non-Hodgkin bone lymphoma.


Asunto(s)
Antineoplásicos/uso terapéutico , Terapia Antirretroviral Altamente Activa , Infecciones por VIH/tratamiento farmacológico , Linfoma Relacionado con SIDA/tratamiento farmacológico , Linfoma de Células B/tratamiento farmacológico , Adolescente , Antígenos CD/inmunología , Recuento de Linfocito CD4 , Infecciones por VIH/complicaciones , Infecciones por VIH/inmunología , VIH-1 , Humanos , Inmunofenotipificación , Linfoma Relacionado con SIDA/complicaciones , Linfoma Relacionado con SIDA/inmunología , Linfoma de Células B/complicaciones , Linfoma de Células B/inmunología , Masculino , Carga Viral
6.
G Ital Nefrol ; 23(2): 203-11, 2006.
Artículo en Italiano | MEDLINE | ID: mdl-16710825

RESUMEN

The 2004 SIN census of the Italian nephrology and dialysis centres showed many interesting data about the epidemiology and the organization in the Regions of Emilia-Romagna (ER) and Tuscany (T). A) Epidemiology: incidence of dialysis patients 169 pmp (patients per million population) in ER, 147 ppm in T; prevalence of dialysis patients 639 pmp and 665 pmp, respectively; prevalence of transplanted patients 325 ppm in ER and 233 pmp in T; gross mortality of dialysis patients 16.3% and 13.4%, respectively; B) Type of vascular access in prevalently dialysis patients: arteriovenous fistula 83% and 78%; central venous catheter 13% and 12%; vascular graft 5% and 9%. C) Structural resources: nephrology beds 44 mp (per million population) and 50 mp; dialysis places 157 and 146 mp. D) Personnel resources : renal physicians 29 and 41 mp; renal nurses 171 and 202 mp ; each renal physician cares for 22 and 16 dialysis patients, and each renal nurse takes care of 3.7 and 3.3 dialysis patients. E) Activity: hospital admissions 1572, 1769 pmp; renal biopsies 115 and 166 pmp.


Asunto(s)
Instituciones de Atención Ambulatoria/estadística & datos numéricos , Unidades de Hemodiálisis en Hospital/estadística & datos numéricos , Sistema de Registros , Diálisis Renal/estadística & datos numéricos , Humanos , Italia
7.
Acta Neurol Scand Suppl ; 116: 13-8, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3043997

RESUMEN

Analytic epidemiology has contributed significantly to the generation and testing of hypotheses of the causes of AD. Several case-control studies have indicated risk factors related to the genetic hypothesis, such as: the presence of cases of either AD or Down's syndrome in other family members and the advanced age of the mother at subject's birth. In this respect recent molecular biology studies on DNA from patients affected by the familial form of AD, have demonstrated a genetic polymorphism localized on chromosome 21. On the same chromosome, the gene coding for beta-amyloid has been also recently localized. Immune, viral and toxic factors, thought to cause AD, have been also investigated in case-control studies, none of them has been found consistently associated with the disease, with the only exception of the head trauma. On the other hand most case-control studies have been carried out in younger cases and no large studies are yet available for late onset patients.


Asunto(s)
Enfermedad de Alzheimer/genética , Aluminio/toxicidad , Enfermedad de Alzheimer/etiología , Enfermedad de Alzheimer/inmunología , Traumatismos Craneocerebrales/complicaciones , Humanos , Metales/toxicidad , Factores de Riesgo
8.
Arch Neurol ; 51(12): 1213-9, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7986176

RESUMEN

OBJECTIVE: To evaluate mean survival and to identify prognostic factors in a cohort of patients with Alzheimer's disease (AD). DESIGN: Multicentric 9-year cohort analytic study. SETTING: Seven neurology departments throughout Italy between April 1982 and January 1984. PATIENTS: We recruited a consecutive sample of 145 patients affected by probable AD (Multicenter Italian Study on Dementia protocol, National Institute of Neurological Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria). Five were misdiagnosed, and 21 could not participate in the longitudinal study. The clinicodemographic characteristics of the 119 enrolled patients (49 men, 70 women; mean age, 64.7 years; SD, 4.1 years; mean duration of disease, 3.1 years; SD, 1.8 years) did not differ from those of the 26 excluded patients. All underwent extensive cliniconeuropsychological testing every 6 months for at least 2 years until the patient died or our survey ended (April 30, 1991). Mean follow-up was 5.1 years (SD, 2.5 years). MAIN OUTCOME MEASURES: Death, severe functional impairment (a score > or = 17 on the Blessed Dementia Scale), and severe cognitive impairment (a score of < or = 7 on the Information-Memory-Concentration Test). RESULTS: Survival curves obtained by the Kaplan-Meier method indicated that (1) patients with early- and late-onset disease (ie, before or after age 65 years) showed no difference either in relative survival or in time to reach predetermined functional and cognitive end points; (2) severely aphasic patients became profoundly demented significantly sooner than those with mild to moderate aphasia (P < .0001). Among clinicodemographic variables analyzed by a Cox model, severe language disability and functional loss proved to be the best predictors of death independent of age at onset or degree of dementia. CONCLUSIONS: Age at onset did not influence course and survival in AD. Severe aphasia appears to be the best predictor of death and unfavorable course.


Asunto(s)
Enfermedad de Alzheimer/mortalidad , Anciano , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/psicología , Femenino , Humanos , Trastornos del Lenguaje/etiología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
9.
Neurology ; 40(4): 626-31, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2320236

RESUMEN

The purpose of this study was to investigate the prevalence of dementia in an Italian population using a door-to-door 2-phase design. As part of a social and health survey, we administered the Hodkinson abbreviated mental test to all persons over age 59 residing in the Commune of Appignano on January 1, 1987 (N = 778). We then investigated all subjects scoring 7 or less on the cognitive test following a standardized diagnostic protocol. We found 48 patients affected by dementia, yielding a crude prevalence ratio (cases per 100 population over age 59) of 6.2; prevalence ratios were 2.6 for Alzheimer's disease, 2.2 for multi-infarct dementia, 0.8 for mixed dementia, 0.4 for secondary dementia, and 0.3 for unspecified dementia. Age- and sex-specific prevalence ratios increased steeply with age and were consistently higher in women for Alzheimer's disease and in men for dementia of all types and multi-infarct dementia. Alzheimer's disease was slightly more frequent than multi-infarct dementia; however, the most common type of dementia varied across age groups. Most cases of Alzheimer's disease were sporadic and had a late age of onset. Comparison with other populations suggests that dementia of all types is as frequent in Appignano as elsewhere, and that Alzheimer's disease might be more frequent in rural than in urban populations.


Asunto(s)
Enfermedad de Alzheimer/epidemiología , Demencia/epidemiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Demografía , Encuestas Epidemiológicas , Humanos , Italia , Masculino , Persona de Mediana Edad , Prevalencia , Población Rural , Factores Sexuales , Población Urbana
10.
Neurology ; 36(7): 922-31, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3714054

RESUMEN

We conducted a case-control study of 116 patients with the clinical diagnosis of Alzheimer's disease (AD) in seven Italian centers. One hundred sixteen hospital controls and 97 population controls were matched by age, sex, and region of residence to the cases. A structured questionnaire was administered to the next-of-kin of cases and controls by trained interviewers to identify possible risk factors. Genetic, viral, toxic, immunologic, medical, surgical, and personality factors were investigated. Dementia among first- or second-degree relatives and advanced age of the mother at subject's birth (age over 40) were associated with AD. Head trauma was more frequent in cases than in either hospital or population controls, but the differences were not significant. Our data did not confirm the previously reported association with antecedent thyroid disease or family history of Down's syndrome.


Asunto(s)
Enfermedad de Alzheimer/etiología , Adulto , Anciano , Demencia/genética , Métodos Epidemiológicos , Familia , Humanos , Italia , Edad Materna , Persona de Mediana Edad , Riesgo
11.
Neurology ; 44(2): 239-42, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8309565

RESUMEN

We assessed the interobserver agreement on the clinical diagnosis of dementia syndrome and dementia subtypes as part of a cross-national project on the prevalence of dementia. Fourteen clinicians from the participating countries (Canada, Chile, Malta, Nigeria, Spain, and the United States) independently assessed the diagnosis of 51 patients whose clinical information was in standard records written in English. We used the DSM-III-R and ICD-10 criteria for dementia syndrome, the NINCDS-ADRDA criteria for Alzheimer's disease (AD), and the ICD-10 criteria for other dementing diseases, and measured interobserver agreement. We found comparable levels of agreement on the diagnosis of dementia using the DSM-III-R (kappa = 0.67) as well as the ICD-10 criteria (kappa = 0.69). Cognitive impairment without dementia was a major source of disagreement (kappa = 0.10). The kappa values were 0.58 for probable AD, 0.12 for possible AD, and rose to 0.72 when the two categories were merged. The interrater reproducibility of the diagnosis of vascular dementia was 0.66 in terms of kappa index; the diagnoses of other dementing disorders as a whole reached a kappa value of 0.40. This study suggests that clinicians from different cultures and medical traditions can use the DSM-III-R and the ICD-10 criteria for dementia effectively and thus reliably identify dementia cases in cross-national research. The interrater agreement on the diagnosis of dementia might be improved if clear-cut guidelines in the definition of cognitive impairment are provided. To improve the reliability of AD diagnosis in epidemiologic studies, we suggest that the NINCDS-ADRDA "probable" and "possible" categories be merged.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Trastornos del Conocimiento/diagnóstico , Demencia/diagnóstico , Variaciones Dependientes del Observador , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/psicología , Canadá , Chile , Demencia/etiología , Femenino , Humanos , Masculino , Malta , Persona de Mediana Edad , Nigeria , Personalidad , España , Estados Unidos
12.
J Med Chem ; 30(5): 768-73, 1987 May.
Artículo en Inglés | MEDLINE | ID: mdl-3572965

RESUMEN

Carbamazepine 10,11-oxide (1a,10b-dihydro-6H-dibenzo[b,f]oxireno[d]azepine-6-carboxamide), a key intermediate in carbamazepine metabolism, was found to be unusually resistant to enzymatic hydrolysis when incubated with microsomal and cytosolic fractions from rabbit, rat, and guinea pig livers. However, its hydrolysis product, trans-10,11-dihydro-10,11-dihydroxy-5H-dibenzo[b,f]azepine-5-carboxamide , was excreted, as previously reported, both in the free and in conjugated forms, as the main metabolite in the urine of humans under carbamazepine treatment. The free diol and that obtained after treatment with beta-glucuronidase/arylsulfatase were both found by Mosher's method to be formed in an enantiomeric excess of 80%, the prevalent enantiomer having the (-)-10S,11S absolute configuration, as determined by applying the CD exciton coupling method to its bis[p-(dimethylamino)benzoyl] ester. This finding confirms the pronounced enantioselectivity of the microsomal epoxide hydrolase toward meso and racemic substrates, but is in contrast with the prevalent formation of (R,R)-diols in most other known cases of enzymatic hydrolysis of epoxides. Preparatively useful syntheses of the racemic trans-10,11-dihydro-10,11-diol and of 9-(hydroxymethyl)-10-carbamoylacridan, another carbamazepine metabolite, are reported for the first time.


Asunto(s)
Carbamazepina/análogos & derivados , Adulto , Animales , Carbamazepina/metabolismo , Carbamazepina/orina , Dicroismo Circular , Citosol/enzimología , Epóxido Hidrolasas/metabolismo , Femenino , Cobayas , Humanos , Hidrólisis , Hígado/enzimología , Espectroscopía de Resonancia Magnética , Masculino , Microsomas Hepáticos/enzimología , Conformación Molecular , Conejos , Ratas , Ratas Endogámicas
13.
Thromb Haemost ; 76(3): 384-92, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8883275

RESUMEN

Enhanced thrombin activity has been associated with coronary thrombosis and with acute and long-term complications following coronary balloon angioplasty. Blocking thrombin activity with specific inhibitors is proposed as a promising antithrombotic therapy. We describe the anticoagulant and antithrombotic properties of hirunorm, a novel synthetic 26-aminoacid peptide thrombin inhibitor, in comparison with r-hirudin and hirulog-1. Hirunorm was equipotent to hirulog-1 and 1/30 as potent as r-hirudin in blocking alpha-thrombin amidolytic activity (IC50 = 10 +/- 2, 15 +/- 1 and 0.3 +/- 0.1 nM, respectively), but it did not affect trypsin, plasmin and t-PA activities at 10 microM. All the compounds inhibited clot-bound thrombin to clots prepared by thrombin hydrolysis of purified fibrinogen in buffer. Hirunorm and hirulog-1 showed similar species-dependent potency in doubling basal in vitro clotting times of human, rat and rabbit plasma (EC200 varied 70 to 200 nM for TT, 0.7 to 16 microM for aPTT and 0.8 to 17 microM for PT), while r-hirudin was always at least three times more active. When assayed by HPLC or by bioassay of the intact peptide, hirunorm was stable against alpha-thrombin and plasma hydrolases, but it was catabolized by rat liver and kidney enzymes. Venous thrombosis was produced in anaesthetized rats by vena cava ligation following a procoagulant serum injection. Intravenous and subcutaneous hirunorm inhibited venous thrombosis at doses (< or = 0.3 mg/kg) two-three times higher than those of r-hirudin. Hirulog-1 was as active as hirunorm only after i.v. infusion. Arterial thrombosis was obtained in the anaesthetized rat by chemical (FeCl2) stimulation of a common carotid and i.v. infused hirunorm (1-3 mg/kg/30 min) inhibited it dose-dependently; r-hirudin was partly active only at 3 mg/kg, but hirulog-1 was inactive at either dose. Full antithrombotic doses of hirunorm did not affect the bleeding time as measured from punctured mesenteric vessels, in anaesthetized rats. In conclusion, hirunorm is a potent peptide thrombin inhibitor endowed with antithrombotic activity in models of venous and arterial thrombosis.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Fibrinolíticos/farmacología , Proteínas/farmacología , Trombosis/tratamiento farmacológico , Venas Cavas/patología , Animales , Tiempo de Sangría , Cromatografía Líquida de Alta Presión , Fibrinolíticos/química , Fibrinolíticos/uso terapéutico , Humanos , Péptidos/química , Péptidos/farmacología , Péptidos/uso terapéutico , Proteínas/química , Proteínas/uso terapéutico , Conejos , Ratas
14.
Br J Pharmacol ; 123(1): 81-91, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9484857

RESUMEN

1. The pharmacological profile was studied of MEN 11420, or cyclo[[Asn(beta-D-GlcNAc)-Asp-Trp-Phe-Dap-Leu]cyclo(2beta-5beta )], a glycosylated derivative of the potent, selective, conformationally-constrained tachykinin NK2 receptor antagonist MEN 10627 (cyclo(Met-Asp-Trp-Phe-Dap-Leu)cyclo(2beta-5beta)). 2. MEN 11420 competitively bound with high affinity to the human NK2 receptor stably transfected in CHO cells, displacing radiolabelled [125I]-neurokinin A and [3H]-SR 48968 with Ki values of 2.5+/-0.7 nM (n = 6) and 2.6+/-0.4 nM (n = 3), respectively. 3. MEN 11420 showed negligible binding affinity (pIC50 < 6) at 50 different receptors (including tachykinin NK1 and NK3 receptors) and ion channels. 4. In the rabbit isolated pulmonary artery and rat urinary bladder MEN 11420 potently and competitively antagonized tachykinin NK2 receptor-mediated contractions (pK(B) = 8.6+/-0.07, n = 10, and 9.0+/-0.04, n = 12; Schild plot slope = -1.06 (95% c.l. = -1.3; -0.8) and -1.17 (95% c.l. = -1.3; -1.0), respectively). MEN 11420 produced an insurmountable antagonism at NK2 receptors in the hamster trachea and mouse urinary bladder. However, in both preparations, the effect of MEN 11420 was reverted by washout and an apparent pK(B) of 10.2+/-0.14, n = 9, and 9.8+/-0.15, n = 9, was calculated in the hamster trachea and mouse urinary bladder, respectively. 5. MEN 11420 showed low affinity (pK(B) < 6) at guinea-pig and rat tachykinin NK1 (guinea-pig ileum and rat urinary bladder) and NK3 (guinea-pig ileum and rat portal vein) receptors. On the whole, the affinities (potency and selectivity) showed by MEN 11420 for different tachykinin receptors, measured either in binding or in functional bioassays, were similar to those shown by the parent compound, MEN 10627. 6. The in vivo antagonism of the contractions produced by [betaAla8]neurokinin A(4-10) (1 nmol kg(-1)) was observed after intravenous (dose range: 1-10 nmol kg(-1)), intranasal (3-10 nmol kg(-1)), intrarectal (30-100 nmol kg(-1)) and intraduodenal (100-300 nmol kg(-1)) administration of MEN 11420. MEN 11420 was more potent (about 10 fold) and longer lasting than its parent compound MEN 10627, possibly due to a greater metabolic stability. 7. A dose of MEN 11420 (100 nmol kg(-1), i.v.), that produced potent and long lasting inhibition of the contraction of the rat urinary bladder induced by challenge with the NK2 selective receptor agonist [betaAla8]neurokinin A(4-10) (10-300 nmol kg(-1)), was without effect on the responses produced by the NK1 receptor selective agonist [Sar9]substance P sulphone (1-10 nmol kg(-1)). 8. These findings indicate that MEN 11420 is a potent and selective tachykinin NK2 receptor antagonist. The introduction of a sugar moiety did not produce major changes in the affinity profile of this antagonist as compared to MEN 10627, but markedly improved its in vivo potency and duration of action. With these characteristics, MEN 11420 is a suitable candidate for studying the pathophysiological significance of tachykinin NK2 receptors in humans.


Asunto(s)
Péptidos Cíclicos/farmacología , Receptores de Neuroquinina-2/antagonistas & inhibidores , Animales , Células CHO , Cricetinae , Femenino , Cobayas , Humanos , Técnicas In Vitro , Canales Iónicos/efectos de los fármacos , Canales Iónicos/metabolismo , Masculino , Péptidos Cíclicos/antagonistas & inhibidores , Péptidos Cíclicos/farmacocinética , Conejos , Ensayo de Unión Radioligante , Ratas , Ratas Wistar , Receptores de Neuroquinina-1/metabolismo , Receptores de Neuroquinina-2/metabolismo , Receptores de Neuroquinina-3/metabolismo
15.
Biochem Pharmacol ; 45(6): 1358-62, 1993 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-8385462

RESUMEN

Idrapril, the prototype of a new class of angiotensin converting enzyme (ACE) inhibitors, competitively inhibited, with nanomolar apparent Ki, the hydrolysis of hippuryl-glycyl-glycine by rabbit lung ACE. The pre-steady-state analysis of this tight-binding inhibition showed it to be characterized by slow kinetics, but at variance with what was found for enalaprilat in the same conditions, idrapril appeared to act through a simple, single step mechanism. Kinetic Ki and k(on) and k(off) values were 470 pM, 3.0 +/- 1.5 x 10(6) M-1 sec-1 and 1.4 +/- 0.3 x 10(-3) sec-1, respectively.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Ácidos Ciclohexanocarboxílicos/farmacología , Hidroxilaminas/farmacología , Pulmón/enzimología , Animales , Sitios de Unión , Unión Competitiva , Dipéptidos/farmacología , Relación Dosis-Respuesta a Droga , Enalaprilato/farmacología , Cinética , Lisinopril , Pulmón/efectos de los fármacos , Peptidil-Dipeptidasa A/aislamiento & purificación , Conejos
16.
Biochem Pharmacol ; 45(5): 1097-105, 1993 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-8461039

RESUMEN

Rociverine [2-(diethylamino)-1-methylethyl cis-1-hydroxy [bicyclohexyl]-2-carboxylate] citrate (ROC) is an antispasmodic agent therapeutically active in humans at doses of 0.5-1 mg/kg. This study investigated the effect of acute administration of the drug on hepatic microsomal cytochrome P450 (P450)-catalysed drug metabolism. Only high doses (> or = 100 mg/kg) of ROC were able to induce in rats the hepatic microsomal pentoxyresorufin O-depenthylase (PROD) and 16 beta-testosterone hydroxylase activities both associated with P4502B1/2 and the erythromycin N-dimethylase (ErD) and 2 beta-testosterone hydroxylase activities both dependent on P4503A1/2. However, at 100 and 200 mg/kg of ROC, the 16 beta-testosterone hydroxylase and PROD were the most induced activities, suggesting that P4502B1/2 are the isoforms most sensitive to ROC induction. Accordingly, ROC treatment enhanced, in a dose-dependent manner, the amount of P4502B1/2 and 3A1/2 in microsomes as assayed by western blotting. The northern blot analysis of ROC-treated rat liver showed that the P4502B1/2 induction appears to be regulated at the mRNA level as in the induction by phenobarbital (PB). The oxidative metabolism of ROC with hepatic microsomes from control or PB- and ROC-induced rats resulted in a N-deethyl ROC derivative (major metabolite) and an unknown minor ROC derivative. The kinetic parameters for the N-deethylation of ROC were studied with purified P4502B1 and with microsomes from control or rats treated with various inducers (phenobarbital, ethanol, beta-naphthoflavone, dexamethasone and rociverine). It was found that phenobarbital-, dexamethasone- and rociverine-induced microsomes deethylated ROC with a Vmax about five times higher than that (0.9 nmol/min/mg protein) of control microsomes, although with a similar affinity (Km approximately 0.3 mM). In a reconstituted system, the purified P4502B1 metabolized ROC with a high deethylation rate (22 nmol/min/nmol P450). Moreover, the ROC deethylation was inhibited by compounds such as hexobarbital, metyrapone and triacetyloleandomicin, selective inhibitors for P4502B and/or P4503A enzymes. On the other hand ROC, when added in vitro, inhibited the 16 beta- and 2 beta-testosterone hydroxylases and the PROD and ErD activities. Taken together, these results indicate that the ROC-inducible P4502B and P4503A are involved in ROC deethylation. In conclusion, it has been demonstrated that ROC is a weak phenobarbital-like inducer of P450, probably able at high and reiterated doses to alter its own metabolism, at least in the rat liver.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas , Compuestos Bicíclicos con Puentes/farmacología , Ácidos Ciclohexanocarboxílicos , Sistema Enzimático del Citocromo P-450/metabolismo , Isoenzimas/metabolismo , Microsomas Hepáticos/enzimología , Oxidorreductasas/metabolismo , Parasimpatolíticos/farmacología , Acetaldehído/metabolismo , Animales , Western Blotting , Compuestos Bicíclicos con Puentes/antagonistas & inhibidores , Compuestos Bicíclicos con Puentes/metabolismo , Citocromo P-450 CYP2B1 , Citocromo P-450 CYP3A , Sistema Enzimático del Citocromo P-450/genética , Electroforesis en Gel de Poliacrilamida , Inducción Enzimática , Isoenzimas/genética , Cinética , Masculino , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Hibridación de Ácido Nucleico , Oxidorreductasas N-Desmetilantes/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Esteroide Hidroxilasas/metabolismo
17.
Biochem Pharmacol ; 52(8): 1141-6, 1996 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-8937420

RESUMEN

A study on the kinetics of human thrombin inhibition by two novel synthetic peptides (Hirunorm IV and Hirunorm V) and a comparison with recombinant hirudin and a commonly used thrombin inhibitor, Hirulog-1, are reported. The dissociation constants for Hirunorm IV and Hirunorm V were determined by varying the concentration of inhibitors at fixed concentrations of the chromogenic substrate Chromozym-TH (N-tosylglycyl-L-prolyl-L-arginine 4-nitroanilide acetate). Both inhibitors behaved as reversible tight-binding inhibitors of amidolytic thrombin activity. The apparent dissociation constants determined showed a linear dependence on the concentration of substrate; this finding, which indicates that the inhibition was competitive, made possible the estimation of the dissociation constants (KI) for Hirunorm IV and Hirunorm V, which were 0.134 +/- 0.014 nM and 0.245 +/- 0.016 nM, respectively. Similar dissociation constants were also obtained for the two inhibitors when thrombin activity was measured with fibrinogen in the clotting assay. When tested for resistance to thrombin proteolytic activity, both inhibitors were inviolate to cleavage by thrombin. The data obtained demonstrate that both Hirunorm IV and Hirunorm V are potent and stable inhibitors of human thrombin activity.


Asunto(s)
Péptidos/farmacología , Proteínas/farmacología , Inhibidores de Serina Proteinasa/farmacología , Trombina/antagonistas & inhibidores , Secuencia de Aminoácidos , Compuestos Cromogénicos , Hirudinas/análogos & derivados , Hirudinas/farmacología , Humanos , Técnicas In Vitro , Cinética , Datos de Secuencia Molecular , Oligopéptidos , Fragmentos de Péptidos/farmacología , Péptidos/química , Proteínas/química , Proteínas Recombinantes/farmacología , Inhibidores de Serina Proteinasa/química , Especificidad por Sustrato
18.
Bone Marrow Transplant ; 21(11): 1091-5, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9645570

RESUMEN

The optimal dosing schedule of G-CSF for peripheral blood progenitor cell (PBPC) mobilization is still under investigation although many centers use 10 microg/kg/day in a single subcutaneous dose. However, G-CSF clearance increases with increasing absolute neutrophil count (ANC). Hence a G-CSF dosage adjusted to ANC might be a reasonable approach. We measured G-CSF trough serum levels by sandwich ELISA assay at different ANCs in eight patients undergoing treatment with filgrastim at 10 microg/kg/day in a single subcutaneous dose. A total of 26 samples were analyzed, and a strong correlation between increasing ANC and decreasing G-CSF levels was found by linear regression analysis (P < 0.0003, r2 = 0.4199). For ANC values above 5000/microl the trough serum levels, ie 24 h after administration, were consistently below the level that provides maximal clonogenic precursor stimulation in vitro (10 ng/ml). Serial serum G-CSF measurements performed in three patients at 0, 3, 6, 9 and 24 h after G-CSF administration, showed a reduction of the area under the curve (AUC) with increasing ANC. For an ANC of 20000/microl or greater, the G-CSF serum level fell under the maximal in vitro stimulation threshold of 10 ng/ml within 12 h. This preliminary pharmacokinetic data seems to suggest that an ANC-adjusted G-CSF dosing schedule might improve the design of PBPC mobilization regimens.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Factor Estimulante de Colonias de Granulocitos/sangre , Movilización de Célula Madre Hematopoyética/métodos , Trasplante de Células Madre Hematopoyéticas , Adolescente , Niño , Preescolar , Análisis Costo-Beneficio , Esquema de Medicación , Factor Estimulante de Colonias de Granulocitos/economía , Movilización de Célula Madre Hematopoyética/economía , Humanos , Técnicas In Vitro , Inyecciones Subcutáneas , Recuento de Leucocitos , Neoplasias/terapia , Neutrófilos
19.
Bone Marrow Transplant ; 18 Suppl 2: 40-2, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8932797

RESUMEN

The role of autologous bone marrow transplantation (ABMT) in childhood ALL after an isolated extramedullary (IE) relapse is controversial. Between December 1984 and November 1995, 52 children underwent ABMT because of an IE relapse. The data were stored in the AIEOP-BMT Registry. Thirty four children were transplanted in 2nd CR; eighteen > 2nd CR. The median duration of 1st CR was 24 (range 3-69) and 18 (range 3-59) months, respectively. The median interval from last CR to ABMT was 6 (range 1-28) and 3 (range 1-81) months, respectively. The 5 year EFS for patients transplanted in 2nd CR was 67.7%, while the 3 year EFS for patients in > 2nd CR was 16.7%. In conclusion, ABMT was an effective treatment in early IE relapse only if performed in 2nd CR.


Asunto(s)
Trasplante de Médula Ósea , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Recurrencia , Trasplante Autólogo , Resultado del Tratamiento
20.
J Steroid Biochem Mol Biol ; 84(5): 503-12, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12767275

RESUMEN

MEN 11066 is a new non-steroidal compound which potently inhibits human placenta (K(i)=0.5 nM) and rat ovarian (K(i)=0.2 nM) aromatase in vitro. In vivo, a single oral dose of 0.3 mgkg(-1) significantly decreased uterus weight in immature rats after stimulation of uterus growth by androstenedione. MEN 11066 reduced in a dose-dependent manner plasma estradiol levels in adult female rats treated with pregnant mare serum gonadotropin (PMSG). After 2 weeks of repeated daily treatment in adult rats, a significant decrease in uterine weight was observed together with a 65% decrease in plasma estradiol, whereas plasma levels of testosterone, progesterone, aldosterone, corticosterone, cholesterol, LH and FSH were not affected. The lack of any effect by MEN 11066 on adrenal steroids was confirmed by the unchanged plasma corticosterone and aldosterone levels in immature rats and also in adult rats when the repeated treatment with MEN 11066 (15 days) was followed by the administration of a synthetic ACTH analogue. No change in 11beta-hydroxylase or 21-hydroxylase activities was produced in vitro by the addition of 10 microM MEN 11066. Fifteen-day treatment with MEN 11066 did not produce changes in several rat hepatic enzymatic activities involved in the metabolism of xenobiotics. These results demonstrated that MEN 11066 is a potent inhibitor of aromatase which does not interfere with the cytochrome P450 involved in the synthesis of other steroids or in the metabolism of xenobiotics.


Asunto(s)
Inhibidores de la Aromatasa , Benzofuranos/farmacología , Inhibidores Enzimáticos/farmacología , Triazoles/farmacología , Administración Oral , Hormona Adrenocorticotrópica/análogos & derivados , Hormona Adrenocorticotrópica/farmacología , Androstenodiona/farmacología , Animales , Aromatasa/metabolismo , Benzofuranos/química , Sistema Enzimático del Citocromo P-450/efectos de los fármacos , Sistema Enzimático del Citocromo P-450/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Gonadotropinas Equinas/farmacología , Humanos , Hígado/enzimología , Oxigenasas de Función Mixta/antagonistas & inhibidores , Oxigenasas de Función Mixta/metabolismo , Tamaño de los Órganos/efectos de los fármacos , Ovario/enzimología , Placenta/enzimología , Ratas , Ratas Wistar , Esteroides/sangre , Triazoles/química , Útero/efectos de los fármacos , Útero/crecimiento & desarrollo
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