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1.
Arch Environ Occup Health ; 78(2): 98-101, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35400302

RESUMEN

Identifying the source of lead is a key measure in the management of childhood lead poisoning. In cases with multiple potential sources or with unusual circumstances, this identification can be complex. By comparing the lead isotopic ratios (IRs) between the potential sources and the blood sample from the patient, it is possible to identify which source caused the poisoning. We report here the case of a 13-years-old girl, screened for lead poisoning as she was known to eat paint chips from two walls in her apartment. Her blood lead level was 395 µg/L, and the environmental investigation came back negative. X-ray fluorescence found lead concentration in paints to be below the regulatory threshold of 1 mg/cm2. As there was no other potential source of lead exposure in this case, a comparative analysis of the IRs of lead between the child's blood and two presumed sources (bathroom and kitchen paints) was performed. This analysis confirmed the source of lead intoxication to be the paints in the apartment, mostly from the bathroom wall.


Asunto(s)
Intoxicación por Plomo , Plomo , Adolescente , Niño , Femenino , Humanos , Exposición a Riesgos Ambientales/análisis , Isótopos/análisis , Intoxicación por Plomo/etiología , Pintura
2.
Eur J Clin Pharmacol ; 75(4): 519-528, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30554270

RESUMEN

PURPOSE: Lithium (Li), the first-line treatment of bipolar disorder, was first developed as an immediate-release form with a routine therapeutic drug monitoring 12 h after the last dose. In Europe, the most commonly prescribed form is a sustained release (srLi). Yet no pharmacokinetics (PK) study has been published of srLi, administered once a day, in adults. The present study describes srLi PK in the serum and erythrocytes of bipolar patients. METHODS: To assess srLi PK, we studied prospectively 17 French bipolar patients on a median dose of 1000 mg (600-1600) for at least 2 years. Serum (S), erythrocyte (E) concentrations, and urinary (U) amount were collected over 8 h after 15 days of morning intake using monitoring electronic medical system (MEMs). Population PK parameters were estimated using the SAEM algorithm (MONOLIX 4.3.3 software). RESULTS: Using a population approach, we built a PK population model of srLi including one S compartment (VS = 23.0 L, ClS = 1.21 L h-1), one E compartment (VE = 64.7 L, ClSE = 3.63 L h-1, ClES = 9.46 L h-1), and one U compartment (F = 0.62) and estimate the ratio of concentrations to Li in E over S at 0.38 with 27% between-subject variability. CONCLUSION: This is a PK model of srLi once a day in bipolar patients using a population approach simultaneously describing Li concentrations in serum, erythrocytes, and urine which provide an estimate of the ratio of concentration in erythrocyte over serum and its between-subject variability (BSV).


Asunto(s)
Trastorno Bipolar/sangre , Trastorno Bipolar/orina , Eritrocitos/metabolismo , Carbonato de Litio/administración & dosificación , Carbonato de Litio/farmacocinética , Modelos Biológicos , Adulto , Trastorno Bipolar/tratamiento farmacológico , Preparaciones de Acción Retardada , Femenino , Humanos , Carbonato de Litio/sangre , Carbonato de Litio/orina , Masculino
4.
Eur J Neurol ; 24(1): 154-160, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27739240

RESUMEN

BACKGROUND AND PURPOSE: The severity of Wilson's disease (WD) is linked to free copper accumulating in the liver and brain. Exchangeable copper (CuEXC) is a new technique to determine plasmatic copper and is useful in the diagnosis of WD. It is hypothesized that it may also enable a good evaluation of extra-hepatic involvement and its severity. METHODS: Forty-eight newly diagnosed WD patients were prospectively evaluated using hepatic, neurological, ophthalmological and brain magnetic resonance imaging (MRI) scores. Three phenotypic presentations were distinguished: pre-symptomatic, hepatic and extra-hepatic. CuEXC was determined in addition to standard copper assays before decoppering therapy. Correlations between biological parameters and the different scores were determined and compared in the hepatic and extra-hepatic groups. RESULTS: Extra-hepatic patients had significantly higher CuEXC values than those with the hepatic form (P < 0.0001). The overall ability of CuEXC to separate the two forms was satisfactory, with an area under the curve of 0.883 (95% confidence interval 0.771-0.996) and an optimal threshold for extra-hepatic diagnosis of 2.08 µmol/l (sensitivity 85.7%; specificity 94.1%). In extra-hepatic patients, CuEXC was the only biological marker to be positively correlated with the Unified Wilson Disease Rating Score (r = 0.45, P = 0.016), the Kayser-Fleischer ring score (r = 0.46, P = 0.014) and the brain MRI score (r = 0.38, P = 0.048), but it was not correlated with the hepatic score. CONCLUSIONS: Exchangeable copper determination is useful when diagnosing WD as a value >2.08 µmol/l is indicative of the severity of the extra-hepatic involvement. In the case of purely hepatic presentation, atypical or mild neurological signs, it should encourage physicians to search for lesions in the brain and eyes.


Asunto(s)
Encéfalo/diagnóstico por imagen , Cobre/metabolismo , Degeneración Hepatolenticular/diagnóstico , Adolescente , Adulto , Biomarcadores , Femenino , Degeneración Hepatolenticular/diagnóstico por imagen , Degeneración Hepatolenticular/metabolismo , Humanos , Imagen por Resonancia Magnética , Masculino , Sensibilidad y Especificidad , Adulto Joven
5.
Med Sci Law ; 56(2): 107-15, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26130751

RESUMEN

During the Middle Ages and Renaissance, embalming the cadaver of the elite was common practice, being a highly technical treatment mixing vegetal and mineral substances. To assess the exact kind of embalming reserved for the dead body (with the practical necessities of desiccation and good odour), we performed a full biomedical analysis of the mummified remains of John Plantagenet of Lancaster, first Duke of Bedford, regent of France for his nephew, the English King Henri VI (died 1435 AD). Here, we show, among other aspects, that the body was embalmed using substances whose origins were in apothecary and botany: mercury, myrtle, mint, frankincense, lime and, possibly, cinnamon and copper.


Asunto(s)
Cadáver , Personajes , Patologia Forense/historia , Patologia Forense/métodos , Historia del Siglo XV , Humanos
6.
Leukemia ; 29(12): 2277-84, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26108692

RESUMEN

We recently identified that the MEK/ERK1/2 pathway synergized with retinoic acid (RA) to restore both transcriptional activity and RA-induced differentiation in RA-resistant acute promyelocytic leukemia (APL) cells. To target the MEK/ERK pathway, we identified glycogen synthase kinase-3ß (GSK-3ß) inhibitors including lithium chloride (LiCl) as activators of this pathway in APL cells. Using NB4 (RA-sensitive) and UF-1 (RA-resistant) APL cell lines, we observed that LiCl as well as synthetic GSK-3ß inhibitors decreased proliferation, induced apoptosis and restored, in RA-resistant cells, the expression of RA target genes and the RA-induced differentiation. Inhibition of the MEK/ERK1/2 pathway abolished these effects. These results were corroborated in primary APL patient cells and translated in vivo using an APL preclinical mouse model in which LiCl given alone was as efficient as RA in increasing survival of leukemic mice compared with untreated mice. When LiCl was combined with RA, we observed a significant survival advantage compared with mice treated by RA alone. In this work, we demonstrate that LiCl, a well-tolerated agent in humans, has antileukemic activity in APL and that it has the potential to restore RA-induced transcriptional activation and differentiation in RA-resistant APL cells in an MEK/ERK-dependent manner.


Asunto(s)
Antineoplásicos/farmacología , Quinasas MAP Reguladas por Señal Extracelular/fisiología , Glucógeno Sintasa Quinasa 3/fisiología , Leucemia Promielocítica Aguda/tratamiento farmacológico , Cloruro de Litio/farmacología , Quinasas de Proteína Quinasa Activadas por Mitógenos/fisiología , Animales , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Glucógeno Sintasa Quinasa 3 beta , Humanos , Cloruro de Litio/uso terapéutico , Ratones , Proteínas de Fusión Oncogénica/metabolismo , Tretinoina/farmacología
7.
Rev Neurol (Paris) ; 167(6-7): 537-40, 2011.
Artículo en Francés | MEDLINE | ID: mdl-21185579

RESUMEN

We report two patients with myelopathy associated with copper deficiency and pancytopenia. Excessive intake of zinc can lead to a severe deficiency of copper reducing the absorption of ingested copper. The patients had in common consumption of denture adhesive paste containing zinc. In both patients, laboratory tests showed a combination of copper deficiency, hyperzincemia and increased urinary zinc level. The use of a denture cream was stopped. Copper supplementation, initially subcutaneously then oral corrected the copper deficiency and pancytopenia. Clinically, the pain faded but the gait disturbance persisted. Copper deficiency associated with the use of denture cream rich in zinc is an unrecognized cause of myelopathy associated with pancytopenia which should be diagnosed early to establish appropriate therapeutic measures to minimize neurological complications.


Asunto(s)
Cobre/deficiencia , Cementos Dentales/efectos adversos , Dentaduras , Enfermedades de la Médula Espinal/inducido químicamente , Anciano , Electromiografía , Trastornos Neurológicos de la Marcha/inducido químicamente , Trastornos Neurológicos de la Marcha/diagnóstico , Trastornos Neurológicos de la Marcha/fisiopatología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Examen Neurológico , Pancitopenia/inducido químicamente , Enfermedades de la Médula Espinal/metabolismo , Enfermedades de la Médula Espinal/patología , Columna Vertebral/patología , Zinc/efectos adversos , Zinc/sangre , Zinc/orina
8.
J Neurol Neurosurg Psychiatry ; 82(10): 1119-21, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20660913

RESUMEN

INTRODUCTION: Wilson's disease (WD) with neurological presentation is associated with brain lesions classically localised in globus pallidus, putamen, thalamus, mesencephalon, pons and dentate nucleus. Lesions of corpus callosum (CC) have not been studied in a broad population of patients with WD. OBJECTIVE: Evaluation of the frequency of CC lesions in patients with neurological symptoms related to WD. METHOD: The authors included all patients with neurological expression of WD, followed in the French national centre for WD who had a brain MRI between March 2006 and December 2008. The localisation of brain lesions was analysed and the frequency of lesions in CC evaluated. All patients were assessed using the Unified Wilson's Disease Rating Scale. For patients with abnormalities located in CC, a clinical dysconnexion syndrome was investigated. RESULTS: Among 81 patients (45 men, mean age: 34.8 years, from 12 to 74 years) with neurological expression, 42% had white-matter lesions on fluid-attenuated inversion recovery MRI. 23.4% of patients presented CC lesions, limited to the posterior part (splenium). The severity of disability estimated by Unified Wilson's Disease Rating Scale was correlated with the presence of CC lesions on MRI. CONCLUSION: Abnormalities in CC are not unusual (23.4%). Together with lesions of basal ganglia, CC signal changes should suggest the diagnosis of WD.


Asunto(s)
Cuerpo Calloso/patología , Degeneración Hepatolenticular/diagnóstico , Aumento de la Imagen , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Adolescente , Adulto , Anciano , Ganglios Basales/patología , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Examen Neurológico , Adulto Joven
9.
Rev Med Interne ; 31(11): 750-6, 2010 Nov.
Artículo en Francés | MEDLINE | ID: mdl-20554092

RESUMEN

Copper is essential for many enzymatic reactions and in neurotransmitter biosynthesis. Its deficiency or its excess has consequences on many organs, especially the liver and the brain. The biochemical tests performed in case of suspicion of copper metabolism disorder are difficult to analyse. They include the measurement of serum ceruloplasmin, serum copper and 24h urinary copper excretion. The interpretation must take into account the clinical features. We distinguish mainly: (1) copper deficiency, acquired in malabsorption or in copper diet deficiency, or related to a genetic disease (Menkes disease); (2) copper overload, acquired or from a genetic origin (Wilson disease); (3) aceruloplasminemia, reducing ferroxidase activity leading to iron overload. It is important to diagnose these diseases as some of them have an effective treatment if it is started early enough.


Asunto(s)
Cobre/metabolismo , Adenosina Trifosfatasas/metabolismo , Adulto , Transporte Biológico , Encéfalo/metabolismo , Ceruloplasmina/metabolismo , Cobre/sangre , Cobre/deficiencia , Cobre/orina , Degeneración Hepatolenticular/metabolismo , Humanos , Absorción Intestinal , Hígado/metabolismo , Síndrome del Pelo Ensortijado/genética , Enfermedades Metabólicas/metabolismo
10.
J Occup Environ Hyg ; 7(5): 253-60, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20182944

RESUMEN

Despite a dramatic decrease in children's blood lead levels (BLL), lead exposure remains a public health concern because increasing evidence shows effects at very low doses. Lowering BLL still further requires the identification of lead sources and, therefore, new tools to investigate and thus prevent exposure. We describe a procedure that uses both lead concentrations and isotope ratios (IRs) to identify sources of overexposure in homes. Water, dust, and paint chips were sampled from the homes of 21 children with elevated BLL from Aubervilliers (Paris metropolitan area). Lead concentrations of concern were calculated from reverse physiologically based pharmacokinetic modeling for water and dust. Isotope ratio matching of blood and environmental samples (with a lead content above the concentration of concern) was performed by computation of the distance between their IRs. When the IR of the source did not match that of the blood, the source was eliminated as a source of lead intoxication. The number of sources eliminated (per child) due to lead concentration ranged from 14% to 86% (mean 66%) for dust, and 100% for water samples. The number of remaining potential sources eliminated by IR interpretation varied from 0% to 100% for both dust and paint chips (mean 63% and 58%, respectively). IRs made it possible to eliminate at least one source in 20 of 21 cases and identified a single source in 11 of 21. The number of dust and paint sources not eliminated by concentration or IR varied from 8% to 45% (median 18%). The pilot study supports the usefulness of these procedures and the added value of IRs for identifying sources of lead poisoning. However, systematic use should be supported by cost-effectiveness analysis on a larger and more representative population of elevated BLL.


Asunto(s)
Exposición a Riesgos Ambientales/análisis , Isótopos/análisis , Intoxicación por Plomo/etiología , Plomo/sangre , Niño , Preescolar , Análisis Costo-Beneficio , Polvo/análisis , Exposición a Riesgos Ambientales/prevención & control , Vivienda , Humanos , Plomo/análisis , Intoxicación por Plomo/sangre , Pintura/análisis , Proyectos Piloto , Suelo/análisis , Abastecimiento de Agua/análisis
11.
Forensic Sci Int ; 194(1-3): e9-15, 2010 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-19913375

RESUMEN

Archaeological remains can provide concrete cases, making it possible to develop, refine or validate medico-legal techniques. In the case of the so-called 'Joan of Arc's relics' (a group of bone and archaeological remains known as the 'Bottle of Chinon'), 14 specialists analysed the samples such as a cadaver X of carbonised aspect: forensic anthropologist, medical examiners, pathologists, geneticists, radiologist, biochemists, palynologists, zoologist and archaeologist. Materials, methods and results of this study are presented here. This study aims to offer an exploitable methodology for the modern medico-legal cases of small quantities of human bones of carbonised aspect.


Asunto(s)
Huesos/patología , Cremación , Personajes , Antropología Forense/métodos , Momias/patología , Animales , Huesos/química , Radioisótopos de Carbono , Gatos , Conducta Cooperativa , ADN/aislamiento & purificación , Dermatoglifia del ADN/métodos , Elementos Químicos , Francia , Historia Medieval , Humanos , Espectrometría de Masas , Microscopía Electrónica de Rastreo , Reacción en Cadena de la Polimerasa
12.
Med Trop (Mars) ; 69(3): 272-4, 2009 Jun.
Artículo en Francés | MEDLINE | ID: mdl-19702150

RESUMEN

PURPOSE: Peripartum cardiac failure is common in savannah-Sahelian Africa. It is due to a form of dilated cardiomyopathy (DCM) known as peripartum cardiomyopathy (PPCM) that results from undetermined causes. Numerous risk factors have been identified and dietary selenium deficiency has been proposed as a possibility. The purpose of this study was to measure serum selenium levels in patients presenting cardiac insufficiency due to PPCM and DCM (nonpostpartum) in Cotonou, Benin and to compare patients with healthy postpartum women with comparable or identical obstetric features. METHODS: Measurements of selenium status were performed in 10 women (mean age, 27.1 years) with PPCM, 18 patients of both sexes (male/female, 11/7; mean age, 38.9 years) with DCM (non-peripartum), and 46 healthy recent post partum women (mean age, 29.8 years). The Wilcoxon nonparametric test was used for data analysis with a statistical significance level at a p-value <0.05. RESULTS: Mean serum selenium values were near similar in patients presenting PPCM and DCM (non peripartum): 94 +/- 12 microg/L versus 97 +/- 19 microg/L respectively. This difference was not significant. No value was less than 72 microg/L. Conversely significantly lower mean values were observed in the 46 healthy recent postpartum women: 76 +/- 13 microg/L (p = 0.0002). The lowest value was 57 microg/L. CONCLUSION: Serum selenium measurements in Cotonou showed that levels were higher in patients presenting PPCM or DCM (nonperipartum) than in healthy controls. Extremely low values were never observed. These results differed from those obtained in Bamako, Mali and in Niamey, Niger and argue against considering selenium deficiency as a risk factor for development of DCM (peripartum or not) in Cotonou.


Asunto(s)
Cardiomiopatía Dilatada/sangre , Cardiomiopatía Dilatada/complicaciones , Parto , Complicaciones Cardiovasculares del Embarazo/sangre , Selenio/sangre , Adulto , Benin , Femenino , Humanos , Masculino , Persona de Mediana Edad , Periodo Posparto , Embarazo , Factores de Riesgo
13.
Médecine Tropicale ; 69(3): 272-274, 2009. ilus
Artículo en Francés | AIM (África) | ID: biblio-1266870

RESUMEN

RÉSUMÉ â€¢ Objectifs. L'insuffisance cardiaque péripartum, fréquente en Afrique soudano-sahélienne, est liée à une cardiomyopathie dilatée (CMD) de cause inconnue appelée cardiomyopathie du péripartum (CMPP). Parmi les facteurs de risque identifiés, la carence alimentaire en sélénium est discutée. Le but de ce travail est d'évaluer le taux de sélénium plasmatique de patientes en insuffisance cardiaque par CMD, péripartum ou non, à Cotonou (République du Bénin)et de le comparer à celui de parturientes en bonne santé à statut obstétrical proche ou identique. Méthodologie. Afin de préciser le statut en sélénium à Cotonou les auteurs ont dosé le sélénium plasmatique chez 10 béninoises(âge moyen = 27,1 ans) atteintes de CMPP, chez 18 patients/es atteints/es de CMD (11 femmes,7 hommes, âge moyen = 38,9 ans) et chez 46 béninoises « témoins » en bonne santé ayant accouché récemment (âge moyen = 29,8 ans). Le test de Wilcoxon (non paramétrique) a été utilisé pour la comparaison statistique avec un seuil < 0,05. Résultat. Les valeurs de sélénémie sont très proches (94 ± 12 µg/L et 97 ± 19 µg/L), avec des différences non significatives, dans les 2 groupes de patients/es porteuses de CMPP ou de CMD.Aucune valeur n'est inférieure à 72 µg/L. Les valeurs sont par contre significativement plus basses(76 ± 13 µg/L, P = 0,0002) chez les 46 témoins, accouchées récentes en bonne santé, la valeur la plus basse étant à 57 µg/L. Conclusion. Les sélénémies des malades, porteuses de CMPP ou de CMD, sont plus élevées que celles des patientes du groupe témoins en bonne santé à Cotonou. Il n'existe aucune valeur très basse (< 40 µg/L), qu'il s'agisse des malades ou des témoins. Ces résultats, différents de ceux observés dans des études antérieures à Bamako (République du Mali) et surtout à Niamey (République du Niger), vont à l'encontre de l'hypothèse d'un déficit en sélénium à l'origine des CMD, péripartum ou non, à Cotonou


Asunto(s)
Cardiomiopatía Dilatada , Insuficiencia Cardíaca , Malí , Niger , Factores de Riesgo , Selenio
14.
J Radiol ; 88(11 Pt 1): 1689-94, 2007 Nov.
Artículo en Francés | MEDLINE | ID: mdl-18065928

RESUMEN

PURPOSE: The quality of magnetic resonance cholangiopancreatography (MRCP) images is frequently degraded by high signal from the gastrointestinal tract on heavily T2W images. The purpose of this study is to evaluate pineapple juice (PJ) as an oral negative contrast agent in MRCP. MATERIALS AND METHODS: Results from MRCP in 50 patients with PJ and 50 patients with paramagnetic contrast (ferumoxsil-Lumirem) were compared. Reviewers were blinded to the type of contrast agent. Exam quality was recorded with regards to signal suppression in the stomach, duodenum and proximal small bowel and with regards to pancreatic duct and biliary ducts visualization. In vitro, the signal characteristics of several commercially available brands of PJ were assessed using T1W, T2W and MRCP sequences. Signal intensity was correlated with the manganese concentration measured using atomic absorption spectrometry. Finally, the reviewers compared the taste of PJ and ferumoxsil. RESULTS: On MRCP sequences, results were similar with regards to signal suppression in the stomach, duodenum and proximal small bowel with PJ and ferumoxsil. Visualization of the pancreatic duct, intrahgepatic bile ducts and CBD was similar with PJ and ferumoxsil. The signal intensity of commercially available brands of PJ on T2W and MRCP sequences correlated well with the measured manganese concentration on spectroscopy. Variations in manganese concentration were observed, with values ranging from 3.65 to 27.24 mg/L. The reviewers noted that PJ tasted "good" or "very good" and that ferumoxsil tasted "bad" or "very bad". CONCLUSION: Ingestion of PJ provides effective signal suppression in the GI tract on MRCP, similar to paramagnetic contrast agents. Because manganese concentration is highly variable in commercially available PJ brands, a brand with high manganese concentration should be selected.


Asunto(s)
Ananas , Bebidas , Pancreatocolangiografía por Resonancia Magnética/métodos , Medios de Contraste , Hierro , Óxidos , Siloxanos , Administración Oral , Distribución de Chi-Cuadrado , Medios de Contraste/administración & dosificación , Óxido Ferrosoférrico , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Nanopartículas de Magnetita , Manganeso/análisis , Espectrofotometría Atómica , Gusto
15.
Toxicol Lett ; 167(3): 221-30, 2006 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-17084997

RESUMEN

The involvement of cytochromes P450 (CYPs) in the oxidation of ethanol into acetaldehyde was investigated by using 16 recombinant human CYP isoforms. Apparent K(m) and V(m) were determined for CYP1A1, CYP1A2, CYP1B1, CYP2A6, CYP2B6, CYP2C8, CYP2C9*1, CYP2C9*2, CYP2C9*3, CYP2C18, CYP2C19, CYP2D6, CYP2E1, CYP2J2, CYP3A4 and CYP4A11. All of the tested CYPs, except CYP2A6 and CYP2C18, metabolized ethanol into significant amounts of acetaldehyde and displayed K(m) values around 10mM. The significant correlation found between ethanol oxidation and CYP2E1, CYP3A4 and CYP1A2 catalytic activities in a panel of human liver microsomes confirmed the strong implication of these CYPs in ethanol metabolism. The contribution of CYP2C isoforms which are the most abundant in the liver after CYP3A4, was studied using selective inhibitors either with recombinant CYP2C isoforms or in human liver microsomes. Tienilic acid (100 microM) and ticlopidine (20 microM), mechanism-based inhibitors of CYP2C9 and CYP2C19, respectively, decreased ethanol oxidation by 8+/-1.2% and 7.6+/-1.6% in human liver microsomal samples while selective inhibitors of CYP2E1 (DEDTC 100 microM), CYP3A4 (TAO 50 microM) and CYP1A2 (furafylline 25 microM) decreased it by 11.9+/-2.1%, 19.8+/-1.9% and 16.3+/-3.9%, respectively. As ethanol can be metabolized by most of CYPs, it helps to explain or predict alcohol-xenobiotics interactions which are of high importance in medical prescription.


Asunto(s)
Acetaldehído/metabolismo , Hidrocarburo de Aril Hidroxilasas/fisiología , Etanol/metabolismo , Microsomas Hepáticos/metabolismo , Oxigenasas de Función Mixta/fisiología , Catálisis , Citocromo P-450 CYP2C19 , Citocromo P-450 CYP2C8 , Citocromo P-450 CYP2C9 , Humanos , Oxidación-Reducción , Proteínas Recombinantes/farmacología
16.
Eur Radiol ; 15(7): 1369-77, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15726379

RESUMEN

This study was designed to compare tumor enhancement by superparamagnetic iron oxide particles, using anionic iron oxide nanoparticles (AP) and ferumoxtran. In vitro, relaxometry and media with increasing complexity were used to assess the changes in r2 relaxivity due to cellular internalization. In vivo, 26 mice with subcutaneously implanted tumors were imaged for 24 h after injection of particles to describe kinetics of enhancement using T1 spin echo, T2 spin echo, and T2 fast spin echo sequences. In vitro, the r2 relaxivity decreased over time (0-4 h) when AP were uptaken by cells. The loss of r2 relaxivity was less pronounced with long (Hahn Echo) than short (Carr-Purcell-Meiboom-Gill) echo time sequences. In vivo, our results with ferumoxtran showed an early T2 peak (1 h), suggesting intravascular particles and a second peak in T1 (12 h), suggesting intrainterstitial accumulation of particles. With AP, the late peak (24 h) suggested an intracellular accumulation of particles. In vitro, anionic iron oxide nanoparticles are suitable for cellular labeling due to a high cellular uptake. Conversely, in vivo, ferumoxtran is suitable for passive targeting of tumors due to a favorable biodistribution.


Asunto(s)
Adenocarcinoma/patología , Medios de Contraste , Aumento de la Imagen/métodos , Hierro , Óxidos , Neoplasias de la Próstata/patología , Adenocarcinoma/metabolismo , Animales , Medios de Contraste/farmacocinética , Dextranos , Modelos Animales de Enfermedad , Espectroscopía de Resonancia por Spin del Electrón , Líquido Extracelular/metabolismo , Óxido Ferrosoférrico , Humanos , Líquido Intracelular/metabolismo , Hierro/farmacocinética , Nanopartículas de Magnetita , Masculino , Ratones , Ratones Desnudos , Nanoestructuras , Trasplante de Neoplasias , Óxidos/farmacocinética , Neoplasias de la Próstata/metabolismo , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Análisis Espectral , Distribución Tisular , Células Tumorales Cultivadas
17.
Leukemia ; 18(9): 1518-21, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15269785

RESUMEN

We previously showed that arsenic trioxide (ATO) and melarsoprol may inhibit the growth of multiple myeloma (MM) cells in vitro and in vivo. We report here the administration of arsenic derivatives in 12 relapsing or refractory secretory MM patients. A total of 10 patients received ATO (eight in a continuous schedule, two discontinuously) and two received melarsoprol. The melarsoprol arm was prematurely closed due to toxicity. In the ATO arm, median duration of treatment was 38 days (9-54). Hepatic toxicity was grade 3 and 2 in one and eight patients, respectively. Other toxicities included neuropathy (n=2, grade 2), encephalitis (n=1, grade 3) and leuconeutropenia (n=4, grade 3). At 2 weeks after treatment initiation, mean serum concentration of arsenic was 1.11+/-0.16 micromol/l. No complete or partial remission was observed. A minor response (25-49% reduction of M protein in serum) and a stabilization of the M-protein level were observed in three and four patients, respectively. After ATO discontinuation, these responses were of short duration in all cases. ATO as a single agent did not produce any significant response in advanced MM patients despite sufficient arsenic exposure. Strategies to improve biodistribution, pharmacokinetic and efficacy of the drug as well as treatment combinations are needed.


Asunto(s)
Antineoplásicos/uso terapéutico , Arsenicales/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Óxidos/uso terapéutico , Anciano , Antineoplásicos/administración & dosificación , Trióxido de Arsénico , Arsenicales/administración & dosificación , Femenino , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Mieloma Múltiple/sangre , Recurrencia Local de Neoplasia/sangre , Óxidos/administración & dosificación , Terapia Recuperativa
18.
Reprod Toxicol ; 15(4): 385-91, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11489594

RESUMEN

Although the main target of lead (Pb) toxicity is the red blood cell, Pb-associated changes in the nervous system, the kidney, and the reproductive system have also been described. The few Pb studies conducted on females revealed mostly miscarriages, premature delivery, and infant mortality in humans and animals. This study was done to correlate Pb accumulation in the ovary with damage to folliculogenesis. Pb burden was assayed by atomic absorption spectrometry in bone, liver, adrenal glands, ovary, and fetuses taken from mice exposed according to 2 protocols: intraperitoneal (i.p.) injection of Pb(NO(3))(2) 10 mg/kg/day for 15 days or 10 mg/kg/week for 15 weeks. Ovaries were examined histologically. Pb accumulation in the various soft tissues of acutely exposed mice was similar, and significantly higher than in the organs of chronically exposed mice. A low Pb concentration in the ovary caused dysfunction of folliculogenesis, with fewer primordial follicles and an increase in atretic antral follicles.


Asunto(s)
Atresia Folicular/metabolismo , Plomo/farmacocinética , Nitratos/farmacocinética , Ovario/metabolismo , Glándulas Suprarrenales/efectos de los fármacos , Glándulas Suprarrenales/metabolismo , Glándulas Suprarrenales/patología , Animales , Peso Corporal/efectos de los fármacos , Femenino , Feto/efectos de los fármacos , Feto/metabolismo , Inyecciones Intraperitoneales , Plomo/administración & dosificación , Plomo/análisis , Plomo/toxicidad , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Nitratos/administración & dosificación , Nitratos/análisis , Nitratos/toxicidad , Tamaño de los Órganos/efectos de los fármacos , Ovario/efectos de los fármacos , Ovario/patología , Embarazo , Espectrofotometría Atómica , Tibia/efectos de los fármacos , Tibia/metabolismo , Factores de Tiempo , Distribución Tisular
19.
Int J Oral Maxillofac Surg ; 30(3): 185-8, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11420898

RESUMEN

It has been shown that titanium (Ti) has had dramatic success in many surgical procedures as a result of its excellent mechanical properties and resistance to corrosion. There is still concern, however, about the release of metal and controversy surrounding whether or not the plates should be removed after bone healing. This study has been conducted to investigate whether or not there is a relationship between duration of plating and metal release from Ti miniplates in maxillofacial surgery. A prospective cohort study design was used. The concentration of Ti, in the soft tissues covering the plates, was examined in all patients who underwent removal of Ti miniplates from January 1998 to April 1999 (51 cases). Inductively Coupled Plasma-Optical Emission Spectrometry was used to measure Ti. Total ti and soluble Ti levels were compared to duration of plating (ranged from 15 days to 3 years, mean = 8 months). Correlation coefficients and two-way ANOVA were data processed. The average amount of total Ti in the soft tissues surrounding the plates was 1306 micrograms/g dry tissue. The mean of soluble Ti was 0.53 microgram/g dry tissue. The results of this study do not support the existence of a relationship between duration of plating and total Ti (correlation coefficient = 0.093 (P > 0.1) nor soluble Ti (correlation coefficient = 0.009 (P > 0.1) in the soft tissue surrounding the plates. Moreover, the only independent factor of Ti release found was associated with mechanical constraints during surgery. Almost 100% of Ti is released during the osteosynthesis. Then Ti levels remain constant in the surrounding tissues. Most of the time, Ti seems to be clinically inert. Compared to the possible risks of a second operation, removal of Ti miniplates should not be a routine procedure except in the case of complaints from patients, particularly in the case of infection, hypersensitivity, dehiscence or screw loosening.


Asunto(s)
Placas Óseas/efectos adversos , Implantación de Prótesis Maxilofacial/efectos adversos , Prostodoncia/métodos , Titanio/farmacocinética , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo , Titanio/efectos adversos , Titanio/orina
20.
J Chromatogr B Biomed Sci Appl ; 740(2): 179-86, 2000 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-10821403

RESUMEN

Hydride generation inductively coupled plasma-atomic emission spectrometry (HG ICP-AES) was used as a continuous detection system for the determination of arsenic in the eluate from a high-performance liquid chromatographic (HPLC) system. Four arsenic species [arsenite As(III), arsenate As(V), monomethylarsonate (MMA), and dimethylarsinate (DMA)] present in the urine samples of patients treated intravenously with arsenite, were analyzed separately by HPLC-HG-ICP-AES using a non-polar C18 column. This analytical method allowed the sensitive determination of the arsenic species in the submicrogram per liter range. Urine samples collected on different days after arsenite administration were found to contain arsenite predominantly--monomethylarsonate and dimethylarsinate were also detected.


Asunto(s)
Arsénico/orina , Arsenicales/farmacocinética , Óxidos/farmacocinética , Trióxido de Arsénico , Arsenicales/administración & dosificación , Calibración , Cromatografía Líquida de Alta Presión , Cisteína/química , Humanos , Indicadores y Reactivos , Inyecciones Intravenosas , Óxidos/administración & dosificación , Reproducibilidad de los Resultados , Soluciones , Espectrofotometría Atómica
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