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1.
Drug Discov Today ; 28(7): 103611, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37164307

RESUMEN

Pharmaceutical companies face challenges in business continuity resulting from declining research and development productivity. This study examines the relationship between two strategic pillars: region and therapeutic area, while considering company size. The results indicate that a therapeutic area focus is an effective strategy for small/medium-sized companies, whereas a regional focus is effective for larger companies. These findings highlight the limitations of the traditional global pharmaceutical model from 2004 to 2018 and aim to contribute to the future corporate strategic planning of these companies.


Asunto(s)
Comercio , Industria Farmacéutica , Industria Farmacéutica/métodos , Pequeña Empresa , Preparaciones Farmacéuticas
2.
Mol Clin Oncol ; 6(6): 871-875, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28588780

RESUMEN

The present study aimed to describe the clinical results of re-irradiation (Re-RT) for spine or pelvic bone metastasis at the same initial irradiated area. Between April 2010 and March 2014, cases involving 98 patients with spine or pelvic bone metastasis who had undergone Re-RT at five institutions were reviewed. The clinical outcomes following Re-RT were evaluated, including overall survival (OS) and severe adverse events. The median time interval from initial radiation therapy (RT) to Re-RT was 439 days (range, 23-4,993 days), and the median duration of patient follow-up was 256 days (range, 11-2,284 days). The median biological effective dose for the Re-RT was 150 Gy2 (range, 17-240 Gy2; α/ß = 2). Severe late adverse events occurred in two patients who underwent three-dimensional conformal radiotherapy for lumbar spine or pelvic bone metastases, which may be associated with tumor progression. The median survival time following Re-RT was 255 days, and the actuarial OS rate at 1 year was 36%. The interval between initial RT and Re-RT, and their performance statuses (PS) were significant independent prognostic factors for OS rates in multivariate analysis. Re-RT for spine or pelvic bone metastases is a relatively acceptable option with low risk of anticipated severe adverse events, particularly for patients with good PS following a long disease-free interval.

3.
J Chromatogr B Analyt Technol Biomed Life Sci ; 802(2): 299-305, 2004 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-15018791

RESUMEN

A simple and rapid assay is described for the simultaneous analysis of levodopa (l-DOPA) and 3-O-methyldopa (3-OMD) in human plasma samples, applying an ion-pair reversed-phase liquid chromatographic method with electrochemical detection, designed for clinical trials performed to study the effect of peripheral catechol-O-methyltransferase inhibitors on the metabolism of l-DOPA. After protein precipitation of 100 microl plasma sample aliquots with perchloric acid, the analytes are directly injected, separated within 10 min and simultaneously quantified down to 20 ng/ml by an electrochemical detector equipped with a dual-electrode system operating in redox mode eliminating effectively potential endogenous and exogenous interferences. The intra-assay precision for l-DOPA and 3-OMD was 1.34-6.54 and 3.90-5.50%, whereas the inter-assay precision was 2.09-7.69 and 4.16-9.90%, respectively. The recoveries were close to 90% for l-DOPA and almost 100% for 3-OMD. Satisfactory storage stability was achieved for up to 16 weeks at -70 degrees C by stabilizing plasma samples with antioxidants.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Electroquímica/métodos , Levodopa/sangre , Tirosina/análogos & derivados , Tirosina/sangre , Calibración , Humanos , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
4.
Rapid Commun Mass Spectrom ; 20(5): 733-40, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16456806

RESUMEN

We have developed a sensitive and specific liquid chromatography/mass spectrometry (LC/MS) method for the simultaneous determination of cyclosporine A (CsA) and its three main metabolites (AM1, AM4N and AM9) in human blood. Following protein precipitation, supernatant was directly injected into the LC/MS system. Chromatographic separation was accomplished on a Symmetry C8 (4.6 x 75 mm, 3.5 microm) column with a linear gradient elution prior to detection by atmospheric pressure chemical ionization (APCI) MS using selected ion monitoring (SIM) in positive mode. This method can be applied to single mass equipment. The analytical range for each analyte was set at 1-2500 ng/mL using 100 microL of blood sample. The analytical method was fully validated according to FDA guidance. Intra-day mean accuracy and precision were 95.2-113.5% and 0.9-8.9%, respectively. Inter-day mean accuracy and precision were 95.8-107.0% and 1.5-10.7%, respectively. In blood all analytes were stable during three freeze/thaw cycles, for 24 h at room temperature and for 12 months at or below -15 degrees C. Stability was also confirmed in processed samples for 24 h at 10 degrees C and for 6 months at 4 degrees C in methanol. In addition, we confirmed the method could avoid matrix effects from transplant subjects' samples. This LC/MS technique provided an excellent method for simultaneous quantitative determination of CsA and its three metabolites for evaluation of their pharmacokinetic profiles.


Asunto(s)
Cromatografía Líquida de Alta Presión , Ciclosporina/sangre , Inmunosupresores/sangre , Espectrometría de Masa por Ionización de Electrospray/métodos , Presión Atmosférica , Criopreservación , Ciclosporina/química , Humanos , Inmunosupresores/química , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados
5.
Biol Pharm Bull ; 26(6): 818-22, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12808293

RESUMEN

We previously reported that fluvastatin, a potent 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, a strong lipid lowering drug, exerted an anti-atherosclerotic effect at doses insufficient to lower serum lipids in cholesterol fed rabbits. The evidence demonstrated that the superoxide anions from nicotinamide adenine dinucleotide phosphate (NADPH) oxidase plays a critical role in several steps in the development of atherosclerosis. This study was designed to determine the effects of HMG-CoA reductase inhibitors on the production of the superoxide anions of NADPH oxidase in isolated rat peritoneal neutrophils. Fluvastatin (1-10 microM) decreased phorbol 12-myristate 13-acetate (PMA, 10 nM)-dependent reactive oxygen species (ROS) generation in a concentration-dependent manner. It also (10 microM) decreased PMA-dependent O(2) consumption of the rat neutrophils. These effects were reversed by the addition of mevalonate, a metabolite in the HMG-CoA reductase pathway. Treatment with pravastatin did not show any significant changes. Fluvastatin (10 microM) decreased ROS, such as hydroxyl radicals and superoxide anions generated by the Fenton reaction, and by the xanthine-xanthine oxidase system. Rats were treated with either fluvastatin (5 mg/kg per day, p.o.) or pravastatin (5 mg/kg per day, p.o.) for 1 week. Treatment with fluvastatin decreased the PMA-dependent ROS generation. The fluvastatin induced effect on the PMA-dependent ROS generation was reversed by the combined administration with 40 mg/kg mevalonate per day. The antioxidative effect of fluvastatin was thought to have caused not only the scavenging action of the radicals but also to have inhibited ROS generation by inhibiting the NADPH oxidase activity. This antioxidative potential of fluvastatin via the inhibition of NADPH oxidase activity may be profitable in preventing atherosclerosis.


Asunto(s)
Antioxidantes/farmacología , Ácidos Grasos Monoinsaturados/farmacología , Indoles/farmacología , NADPH Oxidasas/antagonistas & inhibidores , Especies Reactivas de Oxígeno/metabolismo , Acetato de Tetradecanoilforbol/análogos & derivados , Administración Oral , Animales , Antioxidantes/administración & dosificación , Relación Dosis-Respuesta a Droga , Espectroscopía de Resonancia por Spin del Electrón , Ácidos Grasos Monoinsaturados/administración & dosificación , Fluvastatina , Técnicas In Vitro , Indoles/administración & dosificación , Masculino , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Pravastatina/administración & dosificación , Pravastatina/farmacología , Ratas , Ratas Wistar , Acetato de Tetradecanoilforbol/farmacología
6.
Pharmacology ; 68(3): 121-30, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12784083

RESUMEN

Recent evidence suggests that the beneficial effects of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors on entothelial function and cardiovascular ischemic events may be attributed not only to their lipid-lowering effects but also to cholesterol-lowering independent (direct) effects on the atherosclerotic vessel wall. This study was designed to test the hypothesis that fluvastatin (Flu) preserves the endothelial function by its cholesterol-lowering independent actions. Rabbits were fed a 0.5% high-cholesterol (HC) diet for 12 weeks (progression phase) and then fed the HC diet either containing or not containing Flu 2 mg/kg/day for an additional 8 weeks (treatment phase). Rabbits fed a normal diet were used as controls. Plasma total and low-density lipoprotein cholesterol concentrations did not differ during the treatment phase: Endothelium-dependent/NO-mediated relaxation (acetylcholine and A23187) was impaired in the HC diet group, whereas it was preserved in the HC plus Flu treatment group. The endothelium-independent relaxation (sodium nitroprusside) was similar between the three groups. Interestingly, aortic oxidative stress (lipid peroxides and isoprostane F(2alpha)-III contents) and NADPH oxidase component (p22phox and gp91phox) mRNA expression were increased in the HC group but not in the HC plus Flu group. The A23187-induced nitric oxide production from the aorta was increased in both HC and HC plus Flu groups. There was no significant difference in tissue endothelial-type nitric oxide synthase mRNA expression. Plaque area and intimal thickening of the aorta were significantly lowered in the HC plus Flu group. Flu treatment preserved the endothelial function associated with the decrease in markers of oxidative stress in this experiment. These beneficial endothelial effects of Flu are likely to occur independently of plasma lipid concentrations and to be mediated by its antioxidant action.


Asunto(s)
Antioxidantes/farmacología , Arteriosclerosis/metabolismo , Arteriosclerosis/patología , Endotelio Vascular/efectos de los fármacos , Ácidos Grasos Monoinsaturados/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Indoles/farmacología , Lípidos/sangre , Animales , Anticolesterolemiantes/farmacología , Arteriosclerosis/sangre , Arteriosclerosis/tratamiento farmacológico , Colesterol/sangre , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiología , Fluvastatina , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Hidroximetilglutaril-CoA Reductasas/metabolismo , Hiperlipidemias/sangre , Hiperlipidemias/metabolismo , NADPH Oxidasas/química , NADPH Oxidasas/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa/genética , Estrés Oxidativo/efectos de los fármacos , Fosfolípidos/sangre , Conejos
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