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1.
Hum Reprod ; 32(5): 1046-1054, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28333228

RESUMEN

STUDY QUESTION: How effective is ovarian tissue cryopreservation (OTC)? SUMMARY ANSWER: In our cohort of patients who underwent OTC, premature ovarian failure (POF) rates, return rates and pregnancy rates after autotransplantation were 31.5, 4.4 and 33%, respectively. WHAT IS KNOWN ALREADY: OTC for fertility purposes has been performed for >20 years now. With over 86 live births reported worldwide and success rates of ~30% after autotransplantation of frozen-thawed ovarian cortex, the procedure should no longer be considered experimental. However, very few publications report the efficacy of this procedure. STUDY DESIGN, SIZE, DURATION: Cases of ovarian tissue cryobanking for fertility preservation performed between 1997 and 2013 in a single institution were reviewed by analysis of the cryobank database and a prospective questionnaire sent out in March 2015. PARTICIPANTS/MATERIALS, SETTING, METHODS: There were 545 patients who underwent OTC during this period. The analysis included indications for OTC, survival rates, ovarian function and spontaneous pregnancies after OTC, come-back rates for ovarian tissue transplantation, pregnancy rates after transplantation, and complication and satisfaction rates. MAIN RESULTS AND THE ROLE OF CHANCE: OTC was performed in this cohort at a mean age of 22.3 ± 8.8 years for oncological indications (79%), benign gynecological pathologies (17.5%) and genetic risks of POF (3.5%). Of the 545 patients, 29% were under 18 years of age at the time of OTC and 15% were prepubertal. While 10% of patients died from their disease, 21 patients (3.9%) underwent autotransplantation, 7 of whom delivered a healthy baby, yielding a post-transplantation live birth rate of 33%. Of 451 patients who were sent the questionnaire, 143 agreed to respond (32%). Nevertheless, ovarian function could not be evaluated in 36% of those who answered. Of 92 evaluable patients, 31.5% were menopausal and 68.5% showed persistent ovarian function. Of 52 women who attempted to conceive naturally, 37 were successful (71%). Among 140 patients who answered the questionnaire, 96% were satisfied with the procedure and only 1 major complication (intra-abdominal hemorrhage) was encountered. Among all the patients, 12% have donated their ovarian cortex for research purposes or have had it destroyed. LIMITATIONS, REASONS FOR CAUTION: The questionnaire participation rate (32%), limited follow-up (mean 7.6 ± 3.5 years) and use of only clinical criteria for evaluation of ovarian function made it difficult to accurately assess the risk of POF and efficiency of OTC. WIDER IMPLICATIONS OF THE FINDINGS: Our findings confirm a 30% pregnancy rate after ovarian cortex autotransplantation but also stress the difficulties of evaluating the real efficacy of OTC. STUDY FUNDING/COMPETING INTEREST(S): No funding was sought for this study and none of the authors have any conflict of interest. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registration ID: CRYOFONOV01.


Asunto(s)
Criopreservación/métodos , Preservación de la Fertilidad/métodos , Ovario/patología , Insuficiencia Ovárica Primaria/patología , Adolescente , Adulto , Femenino , Humanos , Satisfacción del Paciente , Embarazo , Índice de Embarazo , Encuestas y Cuestionarios , Adulto Joven
2.
Rev Med Brux ; 38(2): 70-72, 2017.
Artículo en Francés | MEDLINE | ID: mdl-28525246

RESUMEN

After the november 19th 2015 Paris terrorist attacks, there was a clear need to update the Medical Intervention Plans (MIP) for Mass Casualty Events (MCE) in the Brussels Capital Region (BCR), because they only offered a response to single-site MCE in a peace-time context. We compared the organisation and the resources of the BCR and cities like Paris and Lille, we discussed with our french colleagues and formed a Multisite Attack Task-force that produced a specific multisite MIP, which had to be put to use only a few days after its creation.


Les attentats de Paris du 19 novembre 2015 ont mis en avant la nécessité de revoir le Plan d'Intervention médicale (PIM) en cas de catastrophe dans la Région de Bruxelles-Capitale (RBC) car il était axé sur des évènements survenant au niveau d'un seul site et dans un contexte de paix civile. La comparaison de l'organisation et des moyens des villes française comme Paris et Lille, la discussion avec nos collègues français et au sein du Groupe de Travail Attentats Multisites RBC ont permis d'aboutir à Bruxelles à la finalisation d'un PIM multisites qui a été mis à l'épreuve seulement quelques jours après sa création.

3.
Ann Surg Oncol ; 23(8): 2515-21, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27008588

RESUMEN

INTRODUCTION: The direct relationship between surgical radicality to compensate biologic behavior and improvement of patient outcome at the time of primary or interval cytoreduction remains unclear. OBJECTIVE: The aim of this study was to evaluate the impact of disease extension and surgical complexity on survival after complete macroscopic resection for stage IIIC-IV ovarian cancer. MATERIALS AND METHODS: Medical records from seven referral centers in France were reviewed to identify all patients who had complete cytoreductive surgery for stage IIIC-IV epithelial ovarian, fallopian, or primary peritoneal cancer. All patients had at least six cycles of carboplatin and paclitaxel combination therapy. RESULTS: From the 374 consecutive patients with complete cytoreduction who were included in this study, stage, grade, upper abdominal disease, surgical complexity, and carcinomatosis extent were significantly associated with disease-free survival (DFS) at univariate analysis. Stage IV and the need for ultra-radical procedures were significantly associated with lower overall survival (OS). On multivariate analysis, radical surgery, including more than two visceral resections, was significantly associated with decreased DFS and OS. CONCLUSIONS: Patients who need complex surgical procedures involving two or more visceral resections in order to achieve successful complete cytoreduction have worse outcome than patients with less extensive procedures. The negative impact of surgical complexity was not significant in patients who underwent upfront procedures. Tumor volume and extension were associated with decreased DFS in patients undergoing a primary surgical approach. This adds to the evidence that, even though complete cytoreduction is currently the objective of surgery, tumor load remains an independent poor prognostic factor and probably reflects a more aggressive behavior.


Asunto(s)
Procedimientos Quirúrgicos de Citorreducción , Neoplasias Ováricas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica , Carboplatino/administración & dosificación , Femenino , Francia , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología , Paclitaxel/administración & dosificación , Pronóstico , Tasa de Supervivencia , Resultado del Tratamiento , Carga Tumoral
4.
J Clin Pharm Ther ; 34(1): 25-31, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19125900

RESUMEN

BACKGROUND: The use of extemporaneously prepared admixtures of drugs must be supported by documentation of their chemical stability. OBJECTIVE: To assess the physical compatibility and the chemical stability of nefopam hydrochloride, a centrally acting non-opioid analgesic, when admixed with selected proton pump inhibitors (omeprazole, esomeprazole or pantoprazole), in bionolyte G5 injection for intravenous infusion. METHOD: Admixtures were assessed for periods of up to 72 h after storage at ambient temperature without protection from light and at +4 degrees C protected from light. A preparation was considered stable if the compounds of the mixture retained at least 90% of their original potency during the storage. Triplicate samples of nefopam and the selected proton pump inhibitors as well as the following mixtures (nefopam/omeprazole, nefopam/esomeprazole and nefopam/pantoprazole) were prepared in the concentrations required, in polypropylene bottles of bionolyte G5 injection. The physical compatibility was assessed by visual observation at each sampling interval. The chemical stability of the drugs was evaluated by high-performance liquid chromatography and by measurement of pH values. RESULTS: During refrigerated storage, nefopam as well as the selected proton pump inhibitors, when prepared separately in bionolyte G5 injection maintained chemical stability for up to 7 days. At ambient storage conditions, the protons pump inhibitors maintained chemical stability for 24 h, but thereafter their concentrations decreased significantly at day 1. Nefopam maintained chemical stability for up to 72 h at +25 degrees C. Nefopam/omeprazole and nefopam/esomeprazole mixtures in bionolyte were physically incompatible with the mixtures exhibiting a black colour. They underwent rapid and extensive loss, making the combination unacceptable within minutes of mixing. However, the nefopam/pantoprazole mixture was compatible over the study period, but with a reduced duration of the stability. CONCLUSION: Within the limits defined above, nefopam and the selected proton pump inhibitors may be prepared separately in advance in bionolyte G5 injection. The nefopam/pantoprazole mixture was stable for a short period, while the nefopam/omeprazole and the nefopam/esomeprazole mixtures were incompatible and unusable, immediately upon admixture.


Asunto(s)
Analgésicos no Narcóticos/química , Nefopam/química , Soluciones Farmacéuticas/química , Inhibidores de la Bomba de Protones/química , 2-Piridinilmetilsulfinilbencimidazoles/química , Química Farmacéutica , Cromatografía Líquida de Alta Presión , Color , Incompatibilidad de Medicamentos , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Esomeprazol , Humanos , Concentración de Iones de Hidrógeno , Infusiones Intravenosas , Omeprazol/química , Pantoprazol , Temperatura , Factores de Tiempo
5.
J Pharm Biomed Anal ; 37(2): 259-64, 2005 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-15708665

RESUMEN

The stability and compatibility of three drugs: nitroglycerin, diazepam and chlorpromazine, with a new multilayer infusion bag were studied. The study was carried out comparatively with PVC bags with which these drugs are incompatible. The drugs were diluted in 5% dextrose or in 0.9% sodium chloride isotonic solutions. Solutions were stored during 8 or 48 h with or without any protection against light. Remaining concentrations of drug were determined by high-performance liquid chromatography (HPLC) during the storage. The admixtures were also monitored for precipitation, color change and pH. Whatever the isotonic solution used, the loss of drugs is in discredit of the use of PVC bags for their storage. So, these three drugs would not be stored in PVC bags. In multilayer bags, no loss of drugs and no color change were detected throughout the storage period. pH values were stable during the same storage period. These three drugs were compatible with multilayer bags in all tested conditions for 8 or 48 h. The leaching of the plasticizer di-(2-ethylhexyl) phthalate (DEHP), that is incorporated into PVC to make the bags soft and pliable was not detected in the three drug solutions during storage period. Our study confirms that these three drugs are incompatible with PVC bags, on the contrary the new materiel tested was proved to be interesting for drug storage.


Asunto(s)
Materiales Biocompatibles/química , Clorpromazina/química , Diazepam/química , Nitroglicerina/química , Cromatografía Líquida de Alta Presión , Dietilhexil Ftalato/química , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Plastificantes/química , Cloruro de Polivinilo/química , Soluciones
6.
Biochimie ; 66(6): 477-82, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6498230

RESUMEN

With the relation between chemical structure and pharmacological activity as a guide, we have been for some time synthetizing a wide range of beta-amino-ketone derivatives. One of them, 2-(4-methyl-1-piperazinylmethyl) acrylophenone, MPMAP, possesses antimicrotubular activities. This product inhibits 50% of the microtubule polymerization at a 3.10(-5) M concentration. It does not prevent tubulin paracrystal formation induced by vinblastine, and binding experiments reveal that this product is a weak inhibitor of colchicine binding. The structure of this compound is different from the other antimicrotubular agents and has the advantage of being far less complex, highly soluble and easy to synthesize. Thus, this product and related compounds should be a new tool for the study of antimicrotubular activities and tubulin assembly.


Asunto(s)
Proteínas de Microtúbulos/metabolismo , Microtúbulos/efectos de los fármacos , Piperazinas/farmacología , Tubulina (Proteína)/metabolismo , Animales , Encéfalo/metabolismo , Bovinos , Colchicina/metabolismo , Cinética , Microscopía Electrónica , Microtúbulos/ultraestructura , Unión Proteica
7.
J Med Chem ; 30(4): 743-6, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3031294

RESUMEN

Baclofen (beta-p-chlorophenyl-GABA) is the only selective agonist for the bicuculline-insensitive GABAB receptor. We report the synthesis of new GABA analogues and baclofen analogues. In vitro, two compounds, 4-amino-3-benzo[b]furan-2-ylbutanoic acid (9g) and 4-amino-3-(5-methoxybenzo[b]furan-2-yl)butanoic acid (9h), showed an affinity for the GABAB receptor. The results obtained with racemic compounds of benzofuran structure, new for this series, and the surprising inactivity of compound 3a (4-amino-3-(4-hydroxyphenyl)butanoic acid) permit the proposal of an hypothesis for the structure-activity relationships with regard to GABAB receptor.


Asunto(s)
Baclofeno/análogos & derivados , Receptores de GABA-A/efectos de los fármacos , Ácido gamma-Aminobutírico/análogos & derivados , Animales , Baclofeno/síntesis química , Baclofeno/metabolismo , Baclofeno/farmacología , Corteza Cerebral/metabolismo , Masculino , Ratas , Ratas Endogámicas , Receptores de GABA-A/metabolismo , Receptores de GABA-B , Estereoisomerismo , Relación Estructura-Actividad , Ácido gamma-Aminobutírico/síntesis química , Ácido gamma-Aminobutírico/metabolismo , Ácido gamma-Aminobutírico/farmacología
8.
J Med Chem ; 34(8): 2557-60, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1652022

RESUMEN

Baclofen (beta-(p-chlorophenyl)-GABA) is a selective agonist for the bicuculline-insensitive GABAB receptor. The search for new compounds that bind to the GABAB receptor is very important to clarify structural requirements. We report herein the synthesis and the binding studies of variously substituted 3-thienyl- and 3-furylaminobutyric acids. 4-Amino-3-(5-methyl-2-thienyl)butyric acid (5d) and 4-amino-3-(5-chloro-2-thienyl)butyric acid (5h) are potent and specific ligands for GABAB receptor. The IC50 values for the displacement of (R)-(-)-[3H]baclofen are 1.34 and 0.61 microM for 5d and 5h, respectively, as compared to 0.33 microM for baclofen.


Asunto(s)
Furanos/síntesis química , Receptores de GABA-A/metabolismo , Tiofenos/síntesis química , Ácido gamma-Aminobutírico/análogos & derivados , Animales , Baclofeno/metabolismo , Unión Competitiva , Encéfalo/metabolismo , Fenómenos Químicos , Química , Furanos/metabolismo , Estructura Molecular , Muscimol/metabolismo , Ratas , Membranas Sinápticas/metabolismo , Tiofenos/metabolismo , Ácido gamma-Aminobutírico/síntesis química , Ácido gamma-Aminobutírico/metabolismo
9.
J Med Chem ; 28(12): 1934-43, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3934386

RESUMEN

The synthesis of a series of 1-[(4-fluorophenyl)methyl]-N-(4-piperidinyl)-1H-benzimidazol-2-ami nes and the preliminary evaluation of their in vivo antihistamine activity are described. The title compounds were obtained starting from either 1, 4, 10, or 55 by different synthetic methods. Substitution on the phenyl nucleus of the benzimidazole ring (84-87) was achieved by two different approaches. The in vivo antihistamine activity was evaluated by the compound 48/80 induced lethality test in rats and the antihistamine-induced lethality test in guinea pigs after oral and/or subcutaneous administration. The duration of action was studied in the guinea pig for three compounds (4, 51, and 55). Compound 51, "astemizole", was also studied in histamine- and serotonin-induced cutaneous reaction and for mydriatic activity in the rat and tested for peripheral and central effects not related to histamine antagonism in a variety of systems. Astemizole has been selected for clinical investigation.


Asunto(s)
Bencimidazoles/farmacología , Antagonistas de los Receptores Histamínicos/farmacología , Piperidinas/farmacología , Administración Oral , Animales , Astemizol , Bencimidazoles/administración & dosificación , Bencimidazoles/síntesis química , Fenómenos Químicos , Química , Cobayas , Histamina/farmacología , Masculino , Piperidinas/administración & dosificación , Piperidinas/síntesis química , Pupila/efectos de los fármacos , Ratas , Ratas Endogámicas , Serotonina , Pruebas Cutáneas , Relación Estructura-Actividad , p-Metoxi-N-metilfenetilamina/farmacología
10.
J Med Chem ; 28(12): 1943-7, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3934387

RESUMEN

To study the bioisosteric replacement of a 2-pyridyl ring for a phenyl nucleus in astemizole, a series of N-(4-piperidinyl)-3H-imidazo[4,5-b]pyridin-2-amines was synthesized and evaluated. The title compounds were obtained starting from either 8a or 8b by four synthetic methods. The in vivo antihistamine activity was evaluated by the compound 48/80-induced lethality test in rats and the histamine-induced lethality test in guinea pigs after oral and/or subcutaneous administration. Compound 37, the isostere of astemizole, showed the most potent antihistaminic properties in the rat. However, astemizole is superior to 37 as to duration of action and total potency.


Asunto(s)
Aminopiridinas/farmacología , Antagonistas de los Receptores Histamínicos/farmacología , Imidazoles/farmacología , Piperidinas/farmacología , Administración Oral , Aminopiridinas/administración & dosificación , Aminopiridinas/síntesis química , Animales , Astemizol , Bencimidazoles/farmacología , Cobayas , Histamina/farmacología , Antagonistas de los Receptores Histamínicos/administración & dosificación , Antagonistas de los Receptores Histamínicos/síntesis química , Imidazoles/administración & dosificación , Imidazoles/síntesis química , Masculino , Piperidinas/administración & dosificación , Piperidinas/síntesis química , Ratas , Ratas Endogámicas , Relación Estructura-Actividad , p-Metoxi-N-metilfenetilamina/farmacología
11.
J Med Chem ; 28(12): 1925-33, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-4068010

RESUMEN

The synthesis of a series N-(4-piperidinyl)-1H-benzimidazol-2-amines and the preliminary evaluation of their in vitro and in vivo antihistaminic activity are described. Cyclodesulfurization of (2-aminophenyl)thioureas with mercury(II) oxide resulted in 2-aminobenzimidazole intermediates, which were monoalkylated on the endo-nitrogen atom. After deprotection of the piperidine nitrogen atom with 48% aqueous hydrobromic acid solution, the title compounds were obtained by three different methods, viz. alkylation, reductive amination, or oxirane ring-opening reactions. The in vivo antihistaminic activity was evaluated by the compound 48/80 induced lethality test in rats and histamine-induced lethality test in guinea pigs after oral and/or subcutaneous administration. The duration of action, for a selected number of compounds, was studied in the guinea pig. The phenylethyl derivatives showed the most potent antihistamine properties after oral administration in both animal species.


Asunto(s)
Bencimidazoles/farmacología , Antagonistas de los Receptores Histamínicos/farmacología , Piperidinas/farmacología , Administración Oral , Animales , Bencimidazoles/administración & dosificación , Bencimidazoles/síntesis química , Bioensayo , Fenómenos Químicos , Química , Cobayas , Histamina/farmacología , Antagonistas de los Receptores Histamínicos/síntesis química , Íleon/fisiología , Masculino , Contracción Muscular/efectos de los fármacos , Piperidinas/administración & dosificación , Piperidinas/síntesis química , Ratas , Ratas Endogámicas , Relación Estructura-Actividad , p-Metoxi-N-metilfenetilamina/farmacología
12.
APMIS ; 108(6): 417-21, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11028804

RESUMEN

In the present study we compared seven different methods for isolating rabbit polymorphonuclear neutrophils (PMNs) with a view to assessing viability, lymphocyte contamination and isolation yield. The two methods offering the best isolation yield and functional PMNs were retained. Leukocyte-containing plasma fraction was obtained after erythrocyte sedimentation with dextran. First, PMNs were isolated from this fraction, using hypotonic ammonium chloride haemolysis followed by Histopaque density gradient centrifugation (Method-A). Second, PMNs were obtained from leukocyte-containing plasma after centrifugation on two Percoll layers (Method-B). These processes resulted in a high cellular yield: 2.66x10(6)+/-0.22 PMNs per ml of blood (Method-A) and 1.87x10(6)+/-0.37 PMNs per ml of blood (Method-B). In both cases the PMNs isolated were of high purity and viability. In comparison, when using the standard techniques for rabbit - consisting of ammonium chloride haemolysis taking at least four times as long--fewer PMNs were isolated. The PMNs isolated by Method-A and -B were able to generate a high amount of reactive oxygen species (ROS) after stimulation with phorbol 12-myristate 13-acetate (PMA). These methods to separate PMNs are recommended for in vitro studies.


Asunto(s)
Cloruro de Amonio/farmacología , Hemólisis/fisiología , Neutrófilos/citología , Neutrófilos/fisiología , Animales , Separación Celular/métodos , Supervivencia Celular , Hemólisis/efectos de los fármacos , Técnicas In Vitro , Recuento de Leucocitos , Masculino , Conejos , Especies Reactivas de Oxígeno/metabolismo , Superóxidos/sangre
13.
APMIS ; 102(2): 119-21, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8167007

RESUMEN

A gradient separation technique followed by isotonic ammonium chloride haemolysis was compared with two methods for the isolation of polymorphonuclear neutrophils from blood. This technique provided a high yield, excellent purity without lymphocyte and erythrocyte contamination, and made it possible to isolate more than 50 x 10(6) human neutrophils from 15 ml of blood. The polymorphonuclear neutrophils isolated in this way were capable of generating a large amount of reactive oxygen species. This technique for the separation of polymorphonuclear neutrophils is an effective method for in vitro studies.


Asunto(s)
Separación Celular/métodos , Neutrófilos/citología , Supervivencia Celular , Centrifugación por Gradiente de Densidad/métodos , Hemólisis , Humanos , Peróxido de Hidrógeno/sangre , Recuento de Leucocitos , Linfocitos/citología , Neutrófilos/metabolismo , Superóxidos/metabolismo
14.
Biomaterials ; 20(7): 655-61, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10208408

RESUMEN

The stability and compatibility of 5-fluorouracil (5-FU) in undiluted or diluted admixtures stored in beta-radiation sterilized portable poly(vinyl chloride) (PVC) infusion bags were investigated. Admixtures containing 5-FU 50 mg ml(-1) not diluted or 25 mg ml(-1) diluted in 0.9% sodium chloride injection were placed in 100 or 250 ml empty PVC reservoirs sterilized initially by beta-irradiation. They were protected from light and placed at 37 degrees C. Two ml quantities were withdrawn immediately after preparation and after storage for 1, 2, 3, 4, 5, 6, 7 and 14 days. For each condition, samples from each admixture were tested for drug concentration by stability-indicating high-performance liquid chromatography. The admixtures were also monitored for precipitation, color change and pH. Evaporative water loss from the containers was also measured. 5-FU was compatible with PVC containers in all tested conditions for 14 days. No loss of drug and no color change were detected throughout the storage period. pH values were stable and neither precipitation nor loss of water through the reservoirs was observed when drug 50 or 25 mg ml(-1) (diluted using 0.9% sodium chloride) was stored in 100 ml capacity polyvinyl PVC bags. However, when stored in 250 ml capacity PVC bags, the 5-FU solution showed precipitation after 13 and 14 days of storage, but no drug loss was detected due to a substantial loss of water. The precipitation of the drug was due to the decrease of pH induced by the dehydrochlorination of PVC during beta-irradiation leading to the formation of hydrochloric acid in solution. Differences observed between 100 and 250 ml capacity bags can be explained by the greater area of PVC present in 250 ml reservoirs, and consequently more HCl formed. Finally, more plasticizer, di-(2-ethylhexyl) phthalate (DEHP), was then detected in drug solutions stored in 250 ml PVC bags. So, we recommend the use of 100 ml bags to store 5-FU at longer storage times and higher temperatures.


Asunto(s)
Antimetabolitos Antineoplásicos/química , Materiales Biocompatibles , Fluorouracilo/química , Cloruro de Polivinilo , Esterilización/métodos , Antimetabolitos Antineoplásicos/administración & dosificación , Partículas beta , Química Farmacéutica , Cromatografía Líquida de Alta Presión , Dietilhexil Ftalato/química , Estabilidad de Medicamentos , Fluorouracilo/administración & dosificación , Concentración de Iones de Hidrógeno , Infusiones Intravenosas , Plastificantes/química , Soluciones
15.
Int J Antimicrob Agents ; 6(2): 111-8, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18611694

RESUMEN

Trypanothione reductase (TR) is the primary enzyme responsible for the reduction of trypanothione, the analog of glutathione found in trypanosomatidae. We have discovered a series of diphenylsulfides which are potent inhibitors of TR and have no activity on mammalian glutathione reductase. These compounds are also active in vitro on various stages of the parasite. Although structurally related to phenothiazines, which are known to be TR inhibitors, these compounds are devoided of any neuroleptic activity, making them attractive leads to develop specific and non toxic anti-chagasic drugs.

16.
Fundam Clin Pharmacol ; 8(6): 518-24, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7721228

RESUMEN

In smoking subjects with obvious emphysema, the interaction between neutrophil-derived MPO and H2O2 produced by alveolar inflammatory cells (alveolar macrophages (AM) and polymorphonuclear neutrophils (PMN)) has the ability to spontaneously inactivate, in vitro, the alpha 1 proteinase inhibitor (alpha 1PI). This inactivation can induce a desequilibrium of the protease-antiprotease balance in the lungs. In this study, we investigated the ability of glutathione to protect alpha 1PI. In a cellular model of alpha 1PI inactivation mimicking the effects of alveolar inflammatory cells present in the lower respiratory tract of smoking patients with emphysema, we demonstrated that glutathione can protect alpha 1PI against the oxidative inactivation by these activated cells. This protection has been computed in a cellular experimentation (AM and MPO-system) with a 50% inhibitory concentration of 62 microM. Moreover, glutathione has an important inhibitory effect directly on H2O2 released by PMA-stimulated AM (IC50 = 30 microM) or PMA stimulated PMN (IC50 = 70 microM). The mechanism, which governs glutathione may be a result of a scavenging effect on H2O2 as demonstrated in a free cellular experiment. With this in vitro demonstrated effectiveness, glutathione as a therapeutic antioxidant, via the aerosol, has been proposed, in order to prevent tissue damage, inflicted by an excess of activated phagocytic cells, in some lung diseases such as smoking patients with emphysema.


Asunto(s)
Glutatión/farmacología , Peroxidasa/fisiología , Enfisema Pulmonar/tratamiento farmacológico , Fumar/efectos adversos , alfa 1-Antitripsina/metabolismo , Glutatión/uso terapéutico , Humanos , Peróxido de Hidrógeno/metabolismo , Neutrófilos/metabolismo
17.
Fundam Clin Pharmacol ; 13(1): 113-9, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10027097

RESUMEN

The clozapine-induced agranulocytosis could be due to the formation of a reactive intermediate formed in polymorphonuclear neutrophils and granulocyte precursors with the myeloperoxidase-hydrogen peroxide system. On the contrary, no case of agranulocytosis has been described for loxapine, an other neuroleptic drug with a very close structural analogy. We have compared the clozapine and loxapine interaction with the oxidative burst and particularly with this enzymatic complex. On the one hand, the assay of the oxidative species demonstrated a different impact for the two neuroleptics. The 50% inhibitory concentration was 92 microM for hydrogen peroxide and 40 microM for hypochlorous acid for loxapine. The loxapine target is located before the myeloperoxidase-hydrogen peroxide system in the oxidative stream, whereas clozapine diverts the chlorination pathway of the enzyme. On the other hand, the in vitro metabolism of drugs by the myeloperoxidase-hydrogen peroxide system has been investigated by mass spectrometry. Loxapine remains inert but clozapine undergoes the oxidation. The glutathione or ascorbate addition in the medium leads to a removal of the oxidation. Glutathione is able to trap the toxic intermediate and could avoid its formation.


Asunto(s)
Antipsicóticos/farmacología , Clozapina/farmacología , Loxapina/farmacología , Neutrófilos/efectos de los fármacos , Antioxidantes/farmacología , Supervivencia Celular/efectos de los fármacos , Sistema Libre de Células/química , Sistema Libre de Células/efectos de los fármacos , Sistema Libre de Células/metabolismo , Clozapina/química , Glutatión/farmacología , Peroxidasa de Rábano Silvestre/farmacología , Humanos , Peróxido de Hidrógeno/metabolismo , Ácido Hipocloroso/metabolismo , Loxapina/química , Espectrometría de Masas , Neutrófilos/citología , Neutrófilos/metabolismo , Oxidación-Reducción/efectos de los fármacos , Espectrofotometría
18.
Inflammation ; 23(5): 425-36, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10466579

RESUMEN

Investigations are currently being made into the safety of gadolinium complex contrast agents used in Magnetic Resonance Imaging. Their hyperosmolality or potential Gd3+ release is evoked as a cause of various anaphylactoid reactions to be observed in humans after intravenous injection. An estimation has already been made of their effects on the liberation of reactive oxygen intermediates by neutrophils. The purpose of this study was to find a suitable method to measure SOD activity in the presence of these hyperosmolar solutions, and to evaluate their action on this activity. Two techniques were compared to measure this activity. Results and statistical analysis showed that pyrogallol autoxidation was greatly affected by solution osmolalities, whereas ferricytochrome C reduction was not. Gadopentetate dimeglumine and gadoterate meglumine seemed to activate Cu, Zn SOD in vitro, but did not exhibit any SOD-like activity. Gadodiamide did not interfere with this system of detoxication.


Asunto(s)
Medios de Contraste , Gadolinio , Imagen por Resonancia Magnética/métodos , Superóxido Dismutasa/análisis , Medios de Contraste/toxicidad , Relación Dosis-Respuesta a Droga , Gadolinio/toxicidad , Humanos , Superóxido Dismutasa/metabolismo
19.
Inflammation ; 22(2): 191-201, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9561928

RESUMEN

Several antimicrobial agents have already been investigated relating to their influence on neutrophil ROS generation. Azithromycin provides, a dose-related anti-oxidant effect, after 15 min incubation, with the stimulating agent FMLP, as well with PMA or S. aureus. This finding was however obtained with concentrations not considered in therapeutics. Since short incubation times are not representative of the physiological situation, and since azithromycin is characterized by prolonged high concentrations within phagocytes, the same experiments were performed over 2 and 4 h exposures. A time-dependent anti-oxidant effect was then reported. The maximum effect was obtained with PMA (IC50 were 856 and 30 micrograms/ml for 15 min and 4 h incubation times respectively). Time-dependent modifications of neutrophil oxidative metabolism seem to be correlated with intracellular concentrations. Depressed oxidative metabolism might be related neither to azithromycin cellular toxicity, nor to superoxide scavenging properties. By increasing exposure periods, therapeutic concentrations could therefore lead to an anti-inflammatory effect, potentially of clinical interest since associated with bacteriostatic activity.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Azitromicina/farmacología , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Antibacterianos/administración & dosificación , Antioxidantes/administración & dosificación , Azitromicina/administración & dosificación , Sistema Libre de Células , Relación Dosis-Respuesta a Droga , Humanos , Técnicas In Vitro , Cinética , L-Lactato Deshidrogenasa/metabolismo , N-Formilmetionina Leucil-Fenilalanina/farmacología , Neutrófilos/inmunología , Fagocitosis , Especies Reactivas de Oxígeno/metabolismo , Staphylococcus aureus/inmunología , Superóxidos/metabolismo , Acetato de Tetradecanoilforbol/farmacología
20.
Int J Pharm ; 229(1-2): 139-46, 2001 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-11604266

RESUMEN

The leachability of both Di(2-ethylhexyl) phthalate (DEHP) and Tri(2-ethylhexyl) trimellitate (TEHTM) or Trioctyl trimellitate (TOTM) from haemodialysis tubing was investigated in 20 patients with chronic renal failure undergoing maintenance haemodialysis. The blood tubing made of common polyvinyl chloride (PVC) plasticized with DEHP (group 1 patients) were replaced with tubing plasticized with TOTM-DEHP (group 2 patients). The patient blood obtained from the inlet and the outlet of the dialyzer was analyzed during a 4 h-dialysis session. Thus, the circulating concentrations of both DEHP and TOTM resulting from the release from dialyzer tubes were estimated using High-performance Liquid chromatograph (HPLC). With the common PVC-DEHP blood tubing, a DEHP quantity of 122.95+/-33.94 mg was extracted from tubing during a single dialysis session (ranging from 55 to 166.21 mg). During the same period, the total amounts of DEHP retained by the patients were 27.30+/-9.22 mg (ranging from 12.50 to 42.72 mg). As for blood tubing plasticized with TOTM-DEHP, 41.80+/-4.47 mg of DEHP and 75.11+/-25.72 mg of TOTM were extracted. During the same period, the amounts of DEHP and TOTM retained by the patients were 3.42+/-1.37 mg and 4.87+/-2.60 mg, respectively. The extraction rate both plasticizers was correlated with serum lipid content (cholesterol+triglyceride) (r(2)=0.75 for DEHP and r(2)=0.64 for TOTM). In the present investigation, less TOTM and DEHP were apparently released from haemodialysis tubing plasticized with TOTM-DEHP than DEHP released from haemodialysis tubing plasticized with DEHP only. TOTM seems to be a superior alternative to DEHP for use in medical devices because of its potential lower leachability. To recommend it as an alternative plasticizer, its possible toxicity towards human body should be investigated before it can be used routinely. However, patients undergoing haemodialysis using tubing plasticized with DEHP only are regularly exposed to non negligible amounts of DEHP. In view of several biological effects previously reported, it is time to reconsider the use of DEHP only as a plasticizer.


Asunto(s)
Benzoatos/química , Dietilhexil Ftalato/química , Diálisis Renal/instrumentación , Adulto , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Colesterol/sangre , Cromatografía Líquida de Alta Presión , Femenino , Humanos , Masculino , Persona de Mediana Edad , Plastificantes , Plásticos , Espectrofotometría Ultravioleta , Triglicéridos/sangre
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