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1.
Ann Oncol ; 32(10): 1256-1266, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34384882

RESUMEN

BACKGROUND: Late recurrences in postmenopausal women with hormone receptor-positive breast cancers remain an important challenge. Avoidance or delayed development of resistance represents the main objective in extended endocrine therapy (ET). In animal models, resistance was reversed with restoration of circulating estrogen levels during interruption of letrozole treatment. This phase III, randomized, open-label Study of Letrozole Extension (SOLE) studied the effect of extended intermittent letrozole treatment in comparison with continuous letrozole. In parallel, the SOLE estrogen substudy (SOLE-EST) analyzed the levels of estrogen during the interruption of treatment. PATIENTS AND METHODS: SOLE enrolled 4884 postmenopausal women with hormone receptor-positive, lymph node-positive, operable breast cancer between December 2007 and October 2012 and among them, 104 patients were enrolled in SOLE-EST. They must have undergone local treatment and have completed 4-6 years of adjuvant ET. Patients were randomized between continuous letrozole (2.5 mg/day orally for 5 years) and intermittent letrozole treatment (2.5 mg/day for 9 months followed by a 3-month interruption in years 1-4 and then 2.5 mg/day during all of year 5). RESULTS: Intention-to-treat population included 4851 women in SOLE (n = 2425 in the intermittent and n = 2426 in the continuous letrozole groups) and 103 women in SOLE-EST (n = 78 in the intermittent and n = 25 in the continuous letrozole groups). After a median follow-up of 84 months, 7-year disease-free survival (DFS) was 81.4% in the intermittent group and 81.5% in the continuous group (hazard ratio: 1.03, 95% confidence interval: 0.91-1.17). Reported adverse events were similar in both groups. Circulating estrogen recovery was demonstrated within 6 weeks after the stop of letrozole treatment. CONCLUSIONS: Extended adjuvant ET by intermittent administration of letrozole did not improve DFS compared with continuous use, despite the recovery of circulating estrogen levels. The similar DFS coupled with previously reported quality-of-life advantages suggest intermittent extended treatment is a valid option for patients who require or prefer a treatment interruption.


Asunto(s)
Neoplasias de la Mama , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Estrógenos , Femenino , Humanos , Letrozol , Nitrilos/uso terapéutico , Posmenopausia , Receptores de Estrógenos , Receptores de Progesterona , Tamoxifeno/uso terapéutico , Triazoles/uso terapéutico
2.
Rev Med Liege ; 75(12): 767-769, 2020 Dec.
Artículo en Francés | MEDLINE | ID: mdl-33331698

RESUMEN

A young patient consulted in our physical and rehabilitation medicine department following the onset of pain on the scapula area and at the base of his right upper limb after carrying a heavy load. After a couple of weeks, the patient also developed cervical pain. Fortuitously, the cervical scanner displayed a right C6 spondylolysis. Further evaluation by bone scan confirmed that this lesion was not recent and so probably not the cause of the symptoms. Cervical isthmic spondylolysis is a rare condition, much more common at the lumbar level and often ignored at the cervical one. The etiology, pahophysiology, imaging and treatment options for this cervical pathology are discussed in this article.


Un jeune patient a consulté en médecine physique pour des douleurs aux niveaux de l'omoplate et de la racine du membre supérieur droit apparues suite au port d'une charge lourde. Après quelques semaines, le patient se plaignait également de cervicalgies. Un scanner du rachis cervical a objectivé fortuitement une spondylolyse C6 droite. Un bilan complémentaire par scintigraphie osseuse a révélé que la lésion était ancienne et qu'elle n'était probablement pas la cause de la symptomatologie. La lyse isthmique cervicale est une pathologie peu répandue. Très connue à l'étage lombaire, la spondylolyse est rare et souvent ignorée au niveau cervical. L'étiologie, la physiopathologie, l'imagerie et la prise en charge de cette pathologie cervicale sont discutées dans cet article.


Asunto(s)
Espondilólisis , Tomografía Computarizada por Rayos X , Humanos , Vértebras Lumbares , Cuello , Espondilólisis/diagnóstico por imagen
3.
Rev Med Liege ; 72(4): 175-180, 2017 Apr.
Artículo en Francés | MEDLINE | ID: mdl-28471548

RESUMEN

We report the case of a 57-year old man suffering from acute abdominal cramps. Abdominal computed tomography (CT) scanner revealed an isolated dissection of the superior mesenteric artery. The pain decreased within a few days under conservative treatment and monitoring by angioscans showed a stabilization of the dissection. This clinical case report is accompanied by a literature review on this rare pathology.


Ce cas clinique est celui d'un patient de 57 ans souffrant de douleurs abdominales aiguës. La tomodensitométrie abdominale a permis de mettre en évidence une dissection isolée de l'artère mésentérique supérieure. Les douleurs abdominales ont fortement régressé en quelques jours sous traitement conservateur et les angioscanners de suivi ont montré une stabilisation de la dissection. Ce cas clinique permet une revue de la littérature concernant cette pathologie rare.


Asunto(s)
Disección Aórtica/diagnóstico por imagen , Arteria Mesentérica Superior/diagnóstico por imagen , Dolor Abdominal/etiología , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
4.
Rev Med Liege ; 69 Spec No: 12-8, 2014.
Artículo en Francés | MEDLINE | ID: mdl-25796792

RESUMEN

Rupture of abdominal aortic aneurysm (AAA) remains a major cause of death in the elderly. Its prediction is a serious challenge for public health. Despite its regular use to identify patients requiring surgical treatment, the diameter of AAA is not a sufficiently precise and reliable parameter for discriminating aneurysms at high risk of rupture. A better targeting of high risk patients needs understanding in deep the processes and mechanisms directing wall rupture. Inflammation is a significant element in the progression ofAAA and can be visualized using medical imaging techniques such as positron emission tomography (PET) using a glucose derivative (FDG) as radiotracer. Studies conducted in our department have established a relationship between PET positivity and the presence of symptoms such as accelerated growth of the aneurysm or pain, signs generally considered as predictive of rupture. Moreover, activation of leukocytes coupled to cellular and molecular alterations of the aneurysmal wall in the sites of FDG uptake may lead to its instability and incompetence to resist blood pressure and rupture. PET therefore represents a new original exploration method to characterize the severity of AAA progression allowing to assess the need for a surgical treatment much better than does the AAA diameter.


Asunto(s)
Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Tomografía de Emisión de Positrones , Aneurisma de la Aorta Abdominal/diagnóstico , Humanos , Pronóstico
5.
Acta Gastroenterol Belg ; 87(1): 40-43, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38431790

RESUMEN

The authors report the case of a 74-years-old woman treated by immunotherapy for a metastatic renal cell carcinoma and having developed an important cholestasis with thrombocytosis, increased CRP, leucocytosis and hypoalbuminemia. Liver remained free of metastases at medical imaging. The diagnosis of a Stauffer syndrome was confirmed by the hepatic biopsy. A complete response of liver disorders was obtained after nephrectomy. From literature survey, Stauffer syndrome should be kept in mind in cancer patients, especially those suffering from a renal cell carcinoma, presenting with cholestasis with no underlying cause.


Asunto(s)
Carcinoma de Células Renales , Colestasis , Neoplasias Renales , Hepatopatías , Femenino , Humanos , Anciano , Carcinoma de Células Renales/complicaciones , Carcinoma de Células Renales/diagnóstico , Neoplasias Renales/complicaciones , Neoplasias Renales/diagnóstico , Neoplasias Renales/patología , Síndrome , Hepatopatías/diagnóstico , Colestasis/complicaciones
6.
Rev Med Liege ; 68(7-8): 399-401, 2013.
Artículo en Francés | MEDLINE | ID: mdl-24053098

RESUMEN

A case of ulnar artery aneurysm in an independent roofer is reported. It is a rare disease often associated with the Hammer Hypothenar Syndrome specifically found in manual workers and athletes exposed to repetitive palmar trauma.


Asunto(s)
Aneurisma/diagnóstico , Trombosis/diagnóstico , Arteria Cubital/cirugía , Adulto , Aneurisma/cirugía , Industria de la Construcción , Humanos , Masculino , Parestesia/etiología , Radiografía , Trombosis/cirugía , Arteria Cubital/diagnóstico por imagen , Ultrasonografía
7.
Rev Med Liege ; 66(5-6): 285-7, 2011.
Artículo en Francés | MEDLINE | ID: mdl-21826963

RESUMEN

We report a rare case of single cervical metastasis of breast cancer. Bone metastases are the most frequent in breast cancer. Early diagnosis combined with the new therapeutic advances have considerably improved the quality of life and increased the survival. Imaging plays a great role in the diagnosis, particularly scintigraphy and radiography, but sometimes also CT and MRI. The treatment is currently not standardized and it combines hormone therapy, chemotherapy, radiotherapy, and/or surgery.


Asunto(s)
Neoplasias de la Mama/patología , Vértebras Cervicales/patología , Neoplasias de la Columna Vertebral/secundario , Dolor de Espalda/etiología , Femenino , Humanos , Persona de Mediana Edad , Neoplasias de la Columna Vertebral/diagnóstico
8.
Toxicol In Vitro ; 45(Pt 3): 340-350, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28688989

RESUMEN

Recent studies have revealed that particulate matter (PM) exert deleterious effects on vascular function. Pulmonary artery endothelial cells (HPAEC), which are involved in the vasomotricity regulation, can be a direct target of inhaled particles. Modifications in calcium homeostasis and oxidative stress are critical events involved in the physiopathology of vascular diseases. The objectives of this study were to assess the effects of PM2.5 on oxidative stress and calcium signaling in HPAEC. Different endpoints were studied, (i) intrinsic and intracellular production of reactive oxygen species (ROS) by the H2DCF-DA probe, (ii) intrinsic, intracellular and mitochondrial production of superoxide anion (O2-) by electronic paramagnetic resonance spectroscopy and MitoSOX probe, (iii) reactive nitrosative species (RNS) production by Griess reaction, and (vi) calcium signaling by the Fluo-4 probe. In acellular conditions, PM2.5 leads to an intrinsic free radical production (ROS, O2-) and a 4h-exposure to PM2.5 (5-15µg/cm2), induced, in HPAEC, an increase of RNS, of global ROS and of cytoplasmic and mitochondrial O2- levels. The basal intracellular calcium ion level [Ca2+]i was also increased after 4h-exposure to PM2.5 and a pre-treatment with superoxide dismutase and catalase significantly reduced this response. This study provides evidence that the alteration of intracellular calcium homeostasis induced by PM2.5 is closely correlated to an increase of oxidative stress.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Señalización del Calcio/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Material Particulado/toxicidad , Arteria Pulmonar/citología , Adulto , Antioxidantes/farmacología , Calcio/metabolismo , Supervivencia Celular/efectos de los fármacos , Humanos , Masculino , Arteria Pulmonar/efectos de los fármacos , Especies de Nitrógeno Reactivo/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Superóxidos/metabolismo
9.
J Physiol Pharmacol ; 67(4): 617-624, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27779482

RESUMEN

Postoperative development or worsening of obstructive sleep apnea is a potential complication of anesthesia. The objective of this study was to study the effects of a premedication with alprazolam on the occurrence of apneas during the immediate postoperative period. Fifty ASA 1 - 2 patients undergoing a colonoscopy were recruited. Patients with a history of obstructive sleep apnea (OSA) were excluded. Recruited patients were randomly assigned to one of two groups: in Group A, they received 0.5 mg of alprazolam orally one hour before the procedure; and in Group C, they received placebo. Anesthesia technique was identical in both groups. Patients were monitored during the first two postoperative hours to establish their AHI (apnea hypopnea index, the number of apneas and hypopneas per hour). Nine patients were excluded (4 in group A and 5 in group C) due to technical problems or refusal. Interestingly, premedication by alprazolam did not change intra-operative propofol requirements. During the first two postoperative hours, the AHI was significantly higher in group A than in group C (Group A: 20.33 ± 10.97 h-1, C: 9.63 ± 4.67 h-1). These apneas did not induce significant arterial oxygen desaturation, or mandibular instability. Our study demonstrates that a premedication with 0.5 mg of alprazolam doesn't modify intra-operative anesthetic requirements during colonoscopy, but is associated with a higher rate of obstructive apneas during at least three and a half hours after ingestion. No severe side effects were observed in our non-obese population. Our results must be confirmed on a larger scale.


Asunto(s)
Alprazolam/administración & dosificación , Hipnóticos y Sedantes/administración & dosificación , Apnea Obstructiva del Sueño/inducido químicamente , Adulto , Anciano , Alprazolam/uso terapéutico , Analgésicos/uso terapéutico , Anestésicos Intravenosos/uso terapéutico , Colonoscopía , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Hipnóticos y Sedantes/uso terapéutico , Ketamina/uso terapéutico , Masculino , Persona de Mediana Edad , Propofol/uso terapéutico
10.
FEBS Lett ; 459(3): 381-5, 1999 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-10526169

RESUMEN

Regulation of multidrug resistance-associated protein (MRP2) expression in response to dexamethasone (DEX) was analyzed using mainly primary rat hepatocytes. Enhanced levels of MRP2 mRNAs associated with increased amounts of a 190 kDa MRP2 were found in cultured DEX-treated hepatocytes; similarly, administration of DEX to rats (100 mg/kg, i.p.) led to a marked increase of hepatic amounts of MRP2 mRNAs. Maximal induction of MRP2 expression in DEX-treated primary hepatocytes was reached with 10(-5) M DEX, a concentration higher than that (10(-7) M) required for maximal up-regulation of tyrosine aminotransferase (TAT), a typical glucocorticoid receptor-regulated enzyme. In addition, the anti-glucocorticoid compound RU486 failed to inhibit MRP2 induction caused by DEX whereas it fully blocked that of TAT. These findings therefore demonstrate that DEX is a potent inducer of MRP2 expression in rat hepatocytes through a mechanism that seems not to involve the classical glucocorticoid receptor pathway.


Asunto(s)
Dexametasona/farmacología , Hígado/efectos de los fármacos , Proteínas Mitocondriales , Proteínas Ribosómicas/metabolismo , Proteínas de Saccharomyces cerevisiae , Animales , Antiinflamatorios/farmacología , Antagonistas de Hormonas/farmacología , Técnicas In Vitro , Hígado/citología , Hígado/metabolismo , Masculino , Mifepristona/farmacología , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de Glucocorticoides/metabolismo , Proteínas Ribosómicas/efectos de los fármacos , Factores de Tiempo , Regulación hacia Arriba
11.
FEBS Lett ; 443(3): 321-5, 1999 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-10025956

RESUMEN

Cellular and molecular mechanisms involved in the resistance to cytotoxic heavy metals remain largely to be characterized in mammalian cells. To this end, we have analyzed a metal-resistant variant of the human lung cancer GLC4 cell line that we have selected by a step-wise procedure in potassium antimony tartrate. Antimony-selected cells, termed GLC4/Sb30 cells, poorly accumulated antimony through an enhanced cellular efflux of metal, thus suggesting up-regulation of a membrane export system in these cells. Indeed, GLC4/Sb30 cells were found to display a functional overexpression of the multidrug resistance-associated protein MRP1, a drug export pump, as demonstrated by Western blotting, reverse transcriptase-polymerase chain reaction and calcein accumulation assays. Moreover, MK571, a potent inhibitor of MRP1 activity, was found to markedly down-modulate resistance of GLC4/Sb30 cells to antimony and to decrease cellular export of the metal. Taken together, our data support the conclusion that overexpression of functional MRP1 likely represents one major mechanism by which human cells can escape the cytotoxic effects of heavy metals.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Antimonio/farmacología , Resistencia a Múltiples Medicamentos , Metales Pesados/farmacología , Regulación hacia Arriba/efectos de los fármacos , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Transportadoras de Casetes de Unión a ATP/metabolismo , Antimonio/metabolismo , Antineoplásicos/farmacología , Arsenitos/farmacología , Western Blotting , Cloruro de Cadmio/farmacología , Resistencia a Antineoplásicos , Fluoresceínas/metabolismo , Amplificación de Genes/efectos de los fármacos , Humanos , Concentración 50 Inhibidora , Neoplasias Pulmonares , Meglumina/farmacología , Metalotioneína/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Propionatos/farmacología , Quinolinas/farmacología , ARN Mensajero/metabolismo , Células Tumorales Cultivadas , Sulfato de Zinc/farmacología
12.
Biochimie ; 77(4): 233-9, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8589050

RESUMEN

The effects of various concentrations of 2-fluoro-2-deoxy-D-glucose (FDG) on the aerobic metabolism of glucose and the reciprocal effect of glucose on the metabolism of FDG in glucose-grown repressed Saccharomyces cerevisiae cells were studied at 30 degrees C in a standard pyrophosphate medium containing 5 x 10(7) cells/ml by 1H-, 19F-, 31P-NMR and biochemical techniques. The glucose consumption rate is reduced by about 57% and 71% in the presence of 5 mM FDG and 10 mM FDG respectively. Under the same conditions, the ethanol production rate also decreases about 54% and 68%, respectively. When FDG is the unique carbon source, the alpha- and beta-anomers of 2-fluoro-2-deoxy-D-glucose-6-phosphate (FDG6P) and a much smaller quantity of 2-fluoro-2-deoxy-gluconic acid (FDGA) were observed. The quantities of alpha- and beta-FDG6P reach their maximum values within 1 h of incubation and then decrease continuously. In contrast, Glc favors the consumption of FDG and the synthesis of FDG6P and uridine-5'-diphosphate fluorodeoxy-glucose (UDP-FDG). In the presence of Glc, FDG6P reaches a plateau after 1 h or 2 h of incubation while UDP-FDG increases regularly with time. Apart from trehalose, no other disaccharide such as fluoro-dideoxy-trehalose (FDG-FDG) or fluoro-deoxy-trehalose (FDG-Glc) were observed. Thus, in contrast to UDP-Glc, UDP-DG, Glc6P and DG6P, UDP-FDG and FDG6P are not good substrates for trehalose-6-P synthetase.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Desoxiglucosa/análogos & derivados , Glucosa/metabolismo , Glucosa/farmacología , Espectroscopía de Resonancia Magnética/métodos , Saccharomyces cerevisiae/metabolismo , División Celular/efectos de los fármacos , Desoxiglucosa/metabolismo , Desoxiglucosa/farmacología , Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Saccharomyces cerevisiae/efectos de los fármacos
13.
Br J Pharmacol ; 132(3): 778-84, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11159731

RESUMEN

1. Glibenclamide, a sulphonylurea widely used for the treatment of non-insulin-dependent diabetes mellitus, has been shown to inhibit the activities of various ATP-binding cassette (ABC) transporters. In the present study, its effects towards multidrug resistance protein 1 (MRP1), an ABC efflux pump conferring multidrug resistance and handling organic anions, were investigated. 2. Intracellular accumulation of calcein, an anionic dye substrate for MRP1, was strongly increased by glibenclamide in a dose-dependent manner in MRP1-overexpressing lung tumour GLC4/Sb30 cells through inhibition of MRP1-related calcein efflux. By contrast, glibenclamide did not alter calcein levels in parental control GLC4 cells. Another sulphonylurea, tolbutamide, was however without effect on calcein accumulation in both GLC4/Sb30 and GLC4 cells. 3. Glibenclamide used at 12.5 microM was, moreover, found to strongly enhance the sensitivity of GLC4/Sb30 cells towards vincristine, an anticancer drug handled by MRP1. 4. Efflux of carboxy-2',7'-dichlorofluorescein, an anionic dye handled by the ABC transporter MRP2 sharing numerous substrates with MRP1 and expressed at high levels in liver, was also strongly inhibited by glibenclamide in isolated rat hepatocytes. 5. In summary, glibenclamide reversed MRP1-mediated drug resistance likely through inhibiting MRP1 activity and blocked organic anion efflux from MRP2-expressing hepatocytes. Such effects associated with the known inhibitory properties of glibenclamide towards various others ABC proteins suggest that this sulphonylurea is a general inhibitor of ABC transporters.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Gliburida/farmacología , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Análisis de Varianza , Antineoplásicos Fitogénicos/farmacología , Supervivencia Celular , Interacciones Farmacológicas , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Hipoglucemiantes/farmacología , Neoplasias Pulmonares/patología , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Células Tumorales Cultivadas , Vincristina/farmacología
14.
Cancer Lett ; 139(1): 97-104, 1999 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-10408915

RESUMEN

The multidrug resistance-associated protein (MRP) is a drug efflux membrane pump conferring multidrug resistance on tumor cells. In order to look for compounds that can lead to reversal of such a resistance, the antituberculosis compound rifampicin, belonging to the chemical class of rifamycins, was examined for its effect on MRP activity in human multidrug resistant lung cancer GLC4/ADR cells. Rifampicin was shown to increase accumulation of the MRP substrate calcein in GLC4/ADR cells in a dose-dependent manner by inhibiting its MRP-mediated efflux from the cells; it also enhanced intracellular retention of another substrate of MRP such as the anticancer drug vincristine in the resistant cells. By contrast, the antituberculosis drug did not alter cellular levels of accumulation of either calcein or vincristine in parental drug-sensitive GLC4 cells. Other rifamycins such as rifamycin B and rifamycin SV were also demonstrated to increase intracellular accumulation of calcein in GLC4/ADR cells. These results therefore indicate that rifamycins, including rifampicin, probably constitute a new chemical class of modulators down-regulating MRP-mediated drug transport.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Neoplasias Pulmonares/metabolismo , Rifampin/farmacología , Células Tumorales Cultivadas/metabolismo , Antibióticos Antituberculosos/farmacología , Relación Dosis-Respuesta a Droga , Resistencia a Múltiples Medicamentos , Fluoresceínas/metabolismo , Humanos , Modelos Químicos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Rifamicinas/farmacología
15.
Biochem Pharmacol ; 60(12): 1967-75, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11108814

RESUMEN

Organic anion secretion by human hepatocytes was characterized using primary liver parenchymal cell cultures and the anionic fluorescent dye carboxy-2',7'-dichlorofluorescein (CF). Probenecid, a well-known common blocker of the membrane transport process for anions, was shown to increase CF accumulation in primary human hepatocytes by inhibiting cellular CF efflux in a dose-dependent manner, thereby establishing the presence of an efflux system for organic anions in cultured hepatocytes. Outwardly directed transport of CF from hepatocytes was found to be temperature-dependent; it was not altered by changes in the ionic composition of the incubation medium used in efflux experiments. In addition to probenecid, various structurally and functionally unrelated xenobiotics such as glibenclamide, rifampicin, vinblastine, MK-571, indomethacin, and cyclosporin A were shown to inhibit secretion of CF by primary human hepatocytes, thus suggesting that organic anion excretion by human liver may be impaired by various drugs. Northern blot and Western blot analyses of the expression of multidrug resistance proteins (MRP), such as MRP1 and MRP2, which are known to mediate cellular outwardly directed transport of organic anions indicated that MRP2 was present at substantial levels in cultured human hepatocytes as well as in their in vivo counterparts, whereas MRP1 expression was only barely detectable. These results therefore suggest that MRP2, unlike MRP1, may contribute to the organic anion efflux system displayed by primary human hepatocytes and inhibited by a wide range of xenobiotics.


Asunto(s)
Fluoresceínas/metabolismo , Hepatocitos/efectos de los fármacos , Xenobióticos/farmacología , Proteínas de Transporte de Anión , Aniones/metabolismo , Transporte Biológico/efectos de los fármacos , Proteínas Portadoras/metabolismo , Células Cultivadas , Hepatocitos/metabolismo , Humanos
16.
Int J Oncol ; 12(2): 315-9, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9458355

RESUMEN

CD34+ acute myeloid leukemias generally respond poorly to chemotherapy when compared to CD34- myeloid leukemias. In order to contribute to the analysis of the mechanisms involved in this drug resistance, expression and activity of P-glycoprotein (P-gp) and multidrug resistance-associated protein (MRP), two drug efflux pumps conferring multidrug resistance, have been investigated in the CD34+ KG1a leukemic myeloid cell line and in two CD34- K562 and HL60 leukemic myeloid cell lines. Reverse transcription-polymerase chain reaction and dye efflux assays revealed that KG1a cells express P-gp but not MRP whereas neither P-gp nor MRP were detected in K562 and HL60 cells. In addition, KG1a cells were demonstrated to display resistance to anticancer drug substrates for P-gp such as vincristine and daunorubicin and to poorly accumulate vincristine. These results indicated that P-gp, in contrast to MRP, is expressed and functional in the drug-resistant CD34+ KG1a cell line, that may constitute a useful cellular model to analyze the constitutive chemoresistance of CD34+ acute myeloid leukemias.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportadoras de Casetes de Unión a ATP/metabolismo , Daunorrubicina/farmacología , Leucemia Mieloide/tratamiento farmacológico , Vincristina/farmacología , Molécula de Adhesión Celular del Leucocito Activado/fisiología , Antígenos CD34 , División Celular/efectos de los fármacos , Daunorrubicina/uso terapéutico , Resistencia a Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Células HL-60/efectos de los fármacos , Células HL-60/metabolismo , Humanos , Células K562/efectos de los fármacos , Células K562/metabolismo , Datos de Secuencia Molecular , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/metabolismo , Vincristina/uso terapéutico
17.
Int J Oncol ; 15(3): 571-6, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10427142

RESUMEN

Multidrug resistance-associated protein (MRP) and P-glycoprotein are drug efflux pumps conferring multidrug resistance to tumor cells and sharing numerous substrates. In order to determine a flow cytometric assay allowing to analyse MRP activity in cancerous cells in a sensitive and specific manner, cellular accumulation and efflux of the anionic fluorescent dye carboxy-2',7'-dichlorofluorescein (CDF) were studied by flow cytometry using mainly MRP-overexpressing lung GLC4/Sb30 cells and parental GLC4 cells. GLC4/Sb30 cells were found to display reduced accumulation and enhanced efflux of the dye when compared to their parental counterparts. Probenecid, a well known blocker of MRP, strongly enhanced CDF accumulation in GLC4/Sb30 cells through inhibiting efflux of the dye; it also increased CDF levels in GLC4 cells, although to a lesser extent, which may likely be linked to the low, but detectable, expression of MRP in these cells. Comparison of CDF retention with that of calcein demonstrated that the former dye was the most efficiently effluxed by GLC4/Sb30 cells. In contrast to MRP overexpression, that of P-glycoprotein was not found to alter cellular CDF labelling whereas it strongly impaired calcein staining. These results indicate that CDF is a substrate for MRP, but not for P-gp, which may likely be useful for sensitive and specific flow cytometric determination of MRP activity in clinical samples.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/fisiología , Transportadoras de Casetes de Unión a ATP/fisiología , Colorantes , Resistencia a Múltiples Medicamentos , Fluoresceínas , Proteínas de Neoplasias/fisiología , Aniones , Citometría de Flujo , Humanos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Sensibilidad y Especificidad , Células Tumorales Cultivadas
18.
Ann N Y Acad Sci ; 847: 210-9, 1998 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-9668714

RESUMEN

The psychological impact of the announcement of a fetal abnormality after ultrasound examinations is examined in relation to the building up of the mother-child attachment. It represents the "psychological cost" of such techniques. Understanding the subjective experience of the patients could increase the effectiveness of clinical practice. We have assumed that the relationship between parents and professionals is a critical element that contributes to the establishment of an emotional link between the mother and her child. Pregnant women, mothers, and professionals were approached for interviews and by questionnaires including anamnestic data, opinions, and projective methods. The results showed that the women with fetopathy were less centered on themselves during the pregnancy. Long-term effects were found to be important. In pregnant women, ultrasound examination was experienced with satisfaction even if some ambivalence remained. In mothers with an impaired child, ultrasound examination was viewed as a technique with low reliability. Professionals reported not having preparation in making such an announcement. We concluded that a need exists for better management of the modalities of ultrasound examinations. Many parents have expressed their need for psychological support.


Asunto(s)
Anomalías Congénitas/psicología , Feto/anomalías , Madres/psicología , Médicos/psicología , Embarazo/psicología , Adulto , Actitud del Personal de Salud , Actitud Frente a la Salud , Bélgica , Femenino , Ginecología , Humanos , Madres/estadística & datos numéricos , Obstetricia , Médicos/estadística & datos numéricos , Embarazo/estadística & datos numéricos , Encuestas y Cuestionarios
19.
Leuk Lymphoma ; 30(1-2): 163-74, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9669686

RESUMEN

Invasive pulmonary aspergillosis (IPA) is an increasing cause of morbidity and mortality in patients with hematologic malignancies. A major program of construction work close to our unit prompted us to evaluate the efficacy of itraconazole prophylaxis in preventing IPA in these patients. During September 1994 to December 1995, 77 patients undergoing 96 neutropenic episodes (mean duration, 19.3 days +/- 9.1) received itraconazole as antifungal prophylaxis. All patients were treated in laminar air flow rooms. Itraconazole was administered at a loading dose of 600mg/d, (day 1 to day 3) and 400mg/d on the following days, in 87 instances. In the remaining episodes, the daily dose was 200 or 400mg. Oral doses were adjusted to reach a plasma itraconazole level (PIL) above 1000ng/l. In cases of inadequate PIL or poor oral intake, IV AmphoB was started at a 20 mg daily dose. Five cases of IPA (proven n = 2, probable n = 3) were observed. This represents an incidence of 5.2% of the total number of episodes. One out of 67 (2%) treatment episodes with adequate PIL were associated with IPA as compared to 4 of 29 (14%) episodes with inadequate PIL, (p < 0.02). AmphoB was added in 28 cases because of low PIL (n = 25), and/or antibiotic-resistant fever persistent pulmonary infiltrate (n = 8). These results need to be interpreted with caution, because of the absence of randomization or a control group. The efficacy of Itraconazole in neutropenic patients with high risk IPA has to be confirmed on larger and prospective studies.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergilosis Broncopulmonar Alérgica/prevención & control , Itraconazol/uso terapéutico , Neutropenia/complicaciones , Adulto , Aspergilosis Broncopulmonar Alérgica/complicaciones , Aspergilosis Broncopulmonar Alérgica/epidemiología , Monitoreo de Drogas , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Resultado del Tratamiento
20.
Toxicology ; 167(1): 37-46, 2001 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-11557128

RESUMEN

Biliary elimination of endogenous compounds and xenobiotics usually requires carrier-mediated systems allowing movement across the canalicular membrane of hepatocytes. The major systems implicated belong to the ATP binding cassette transporter family: P-glycoprotein (P-gp) and multidrug resistance-associated protein 2 (MRP2), principally mediate the passage into the bile of cationic and anionic compounds, respectively, whereas the bile salt export pump (BSEP) handles biliary acids and also some anticancer drugs. Expression of these canalicular proteins can be altered in response to various hormones and structurally unrelated xenobiotics. Indeed, glucocorticoids up-regulate expression of both MRP2 and BSEP in rat hepatocytes, whereas insulin induces P-gp. P-gp expression is also up-regulated by numerous chemical carcinogens, such as polycyclic aromatic hydrocarbons and 2-acetylaminofluorene and by some anticancer drugs, such as anthracyclins. 2-Acetylaminofluorene also induces MRP2; in addition, expression of this transporter in liver cells is increased in response to various drugs, such as the barbiturate phenobarbital, the chemopreventive agent, oltipraz and the anticancer drug, cisplatin. Most of the chemical inducers acting on canalicular transporter levels are well-known to up-regulate some hepatic drug metabolizing enzymes, suggesting a coordinate regulation of liver detoxifying proteins in response to these compounds.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/biosíntesis , Transportadoras de Casetes de Unión a ATP/biosíntesis , Proteínas Portadoras/biosíntesis , Hormonas/fisiología , Proteínas de Transporte de Membrana , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Xenobióticos/farmacología , Subfamilia B de Transportador de Casetes de Unión a ATP/biosíntesis , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Miembro 11 de la Subfamilia B de Transportador de Casetes de Unión al ATP , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Animales , Proteínas de Transporte de Anión , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Glucocorticoides/fisiología , Humanos , Insulina/fisiología , Proteína 2 Asociada a Resistencia a Múltiples Medicamentos , Regulación hacia Arriba/fisiología
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