Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
J Geophys Res Atmos ; 125(3): e2019JD030692, 2020 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-32714720

RESUMEN

Dong et al. (2020, https://doi.org/10.1029/2019JD030691) employed a new compressible model to examine gravity wave (GW) self-acceleration dynamics, instabilities, secondary gravity wave (SGW) generation, and mean forcing for GW packets localized in two dimensions (2D). This paper extends the exploration of self-acceleration dynamics to a GW packet localized in three dimensions (3D) propagating into tidal winds in the mesosphere and thermosphere. As in the 2D packet responses, 3D GW self-acceleration dynamics are found to be significant and include 3D GW phase distortions, stalled GW vertical propagation, local instabilities, and SGW and acoustic wave generation. Additional 3D responses described here include refraction by tidal winds, localized 3D instabilities, asymmetric SGW propagation, reduced SGW and acoustic wave responses at higher altitudes relative to 2D responses, and forcing of transient, large-scale, 3D mean responses that may have implications for chemical and microphysical processes operating on longer time scales.

2.
JAMA Oncol ; 1(9): 1272-80, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26378637

RESUMEN

IMPORTANCE: Standard therapy for advanced soft-tissue sarcoma has not changed substantially in decades, and patient prognosis remains poor. Aldoxorubicin, a novel albumin-binding prodrug of doxorubicin, showed clinical activity against advanced soft-tissue sarcoma in phase 1 studies. OBJECTIVE: To evaluate efficacy and safety of aldoxorubicin vs doxorubicin in patients with advanced soft-tissue sarcoma. DESIGN, SETTING, AND PARTICIPANTS: International, multicenter, phase 2b, open-label, randomized study at general community practices, private practices, or institutional practices. Between August 2012 and December 2013, 140 patients with previously untreated locally advanced, unresectable, or metastatic soft-tissue sarcoma were screened. INTERVENTIONS: Randomization (2:1) to aldoxorubicin 350 mg/m2 (dose equivalent to doxorubicin 260 mg/m2) or doxorubicin 75 mg/m2, administered once every 3 weeks for up to 6 cycles. MAIN OUTCOMES AND MEASURES: Primary end point was progression-free survival. Secondary end points were 6-month progression-free survival, overall survival, tumor response rate, and safety. All efficacy end points were evaluated by independent and local review. RESULTS: A total of 126 patients were randomized, and 123 received aldoxorubicin (n = 83) or doxorubicin (n = 40). Median (range) patient age was 54.0 (21-77 years); 42 (34%) had leiomyosarcoma. By independent review, median progression-free survival was significantly improved (5.6 [95% CI, 3.0-8.1] vs 2.7 [95% CI, 1.6-4.3] months; P = .02) with aldoxorubicin compared with doxorubicin, as was the rate of 6-month progression-free survival (46% and 23%; P = .02). Median overall survival was 15.8 (95% CI, 13.0 to not available) months with aldoxorubicin and 14.3 (95% CI, 8.6-20.6) months with doxorubicin (P = .21). Overall tumor response rate (by Response Evaluation Criteria in Solid Tumors, version 1.1) by independent review was higher with aldoxorubicin than with doxorubicin (25% [20 patients, all partial response] vs 0%). Grade 3 or 4 neutropenia was more frequent with aldoxorubicin than with doxorubicin (24 [29%] vs 5 [12%]), but not grade 3 or 4 febrile neutropenia (12 [14%] vs 7 [18%]). No acute cardiotoxic effects were observed with either treatment, although left ventricular ejection fraction less than 50% occurred in 3 of 40 patients receiving doxorubicin. CONCLUSIONS AND RELEVANCE: Single-agent aldoxorubicin therapy showed superior efficacy over doxorubicin by prolonging progression-free survival and improving rates of 6-month progression-free survival and tumor response. Aldoxorubicin therapy exhibited manageable adverse effects, without unexpected events, and without evidence of acute cardiotoxicity. Further investigation of aldoxorubicin therapy in advanced soft-tissue sarcoma is warranted. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01514188.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Doxorrubicina/administración & dosificación , Profármacos/administración & dosificación , Sarcoma/tratamiento farmacológico , Adulto , Anciano , Antibióticos Antineoplásicos/efectos adversos , Doxorrubicina/efectos adversos , Doxorrubicina/análogos & derivados , Esquema de Medicación , Métodos Epidemiológicos , Femenino , Humanos , Hidrazonas/administración & dosificación , Hidrazonas/efectos adversos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Profármacos/efectos adversos , Resultado del Tratamiento , Adulto Joven
3.
Invest New Drugs ; 33(2): 341-8, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25388939

RESUMEN

Introduction Aldoxorubicin, a prodrug of doxorubicin, binds covalently to serum albumin in the bloodstream and accumulates in tumors. Aldoxorubicin can be administered at doses several-fold higher than doxorubicin can, without associated acute cardiotoxicity. Purpose This study fully evaluated the pharmacokinetic profile of aldoxorubicin (serum and urine). Methods Eighteen patients with advanced solid tumors received aldoxorubicin 230 or 350 mg/m(2) (equivalent in drug load to doxorubicin at doses of 170 or 260 mg/m(2), respectively) once every 21 days. Blood samples were taken in cycle 1 before aldoxorubicin infusion, and at 5, 15, 30, and 60 min, and at 2, 4, 8, 12, 16, 24, 48, and 72 h after infusion. Urine samples were taken in cycle 1 at 24, 48, and 72 h after infusion. Limited blood sampling was done in cycle 3, before aldoxorubicin infusion, and at 60 min and at 2, 4, and 8 h after infusion. Results The long mean half-life (20.1-21.1 h), narrow mean volume of distribution (3.96-4.08 L/m(2)), and slow mean clearance rate (0.136-0.152 L/h/m(2)) suggest that aldoxorubicin is stable in circulation and does not accumulate readily in body compartments outside of the bloodstream. Very little doxorubicin and its major metabolite doxorubicinol, which has been implicated in doxorubicin-associated cardiotoxicity, are excreted in urine. This might explain the lack of cardiotoxicity observed thus far with aldoxorubicin. Conclusions Our findings support dosing and administration schemas used in an ongoing phase 3 clinical study of aldoxorubicin in soft tissue sarcoma, and phase 2 clinical studies in small cell lung cancer, glioblastoma, and Kaposi's sarcoma.


Asunto(s)
Antibióticos Antineoplásicos/farmacocinética , Doxorrubicina/análogos & derivados , Hidrazonas/farmacocinética , Neoplasias/tratamiento farmacológico , Profármacos/farmacocinética , Adulto , Anciano , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/efectos adversos , Relación Dosis-Respuesta a Droga , Doxorrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Doxorrubicina/farmacocinética , Esquema de Medicación , Femenino , Semivida , Humanos , Hidrazonas/administración & dosificación , Hidrazonas/efectos adversos , Infusiones Intravenosas , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Profármacos/administración & dosificación , Profármacos/efectos adversos
4.
Neoplasia ; 16(10): 874-82, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25379024

RESUMEN

Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor with a median survival of 12 to 15 months after diagnosis. Acquired chemoresistance, high systemic toxicity, and low penetration of the blood brain barrier by many anticancer drugs contribute to the failure of anti-GBM therapies. To circumvent some of these obstacles, we tested a novel prodrug approach to evaluate anti-GBM efficacy by utilizing serum albumin-binding doxorubicin (Doxo), aldoxorubicin (Aldoxo), which is less toxic, is released from albumin in an acidic environment and accumulates in tumor tissues. A human GBM cell line that expresses a luciferase reporter (U87-luc) was stereotactically injected into the left striatum of the brain of immunodeficient mice. Following initial tumor growth for 12 days, mice were injected once a week in the tail-vein with Aldoxo [24 mg/kg or 18 mg/kg of doxorubicin equivalents-3/4 maximum tolerated dose (MTD)], Doxo [6 mg/kg (3/4 MTD)], or vehicle. Aldoxo-treated mice demonstrated significantly slower growth of the tumor when compared to vehicle-treated or Doxo-treated mice. Five out of eight Aldoxo-treated mice remained alive more than 60 days with a median survival of 62 days, while the median survival of vehicle- and Doxo-treated mice was only 26 days. Importantly, Aldoxo-treated mice exhibited high levels of Doxo within the tumor tissue, accompanied by low tumor cell proliferation (Ki67) and abundant intratumoral programmed cell death (cleaved caspase-3). Effective accumulation of Aldoxo in brain tumor tissues but not normal brain, its anti-tumor efficacy, and low toxicity, provide a strong rationale for evaluating this novel drug conjugate as a treatment for patients afflicted with GBM.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Doxorrubicina/análogos & derivados , Doxorrubicina/farmacología , Glioblastoma/tratamiento farmacológico , Hidrazonas/farmacología , Administración Intravenosa , Animales , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacocinética , Femenino , Glioblastoma/mortalidad , Glioblastoma/patología , Humanos , Hidrazonas/farmacocinética , Dosis Máxima Tolerada , Ratones Desnudos , Factores de Tiempo , Resultado del Tratamiento , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Expert Opin Investig Drugs ; 18(12): 1907-18, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19938902

RESUMEN

Arimoclomol, an amplifier of heat shock protein expression involved in cellular stress response, has emerged as a potential therapeutic candidate in amyotrophic lateral sclerosis (ALS) in recent years. Treatment with arimoclomol was reported to improve survival and muscle function in a mouse model of motor neuron disease. Several single- and multiple-dose safety studies have been completed in healthy control subjects. A 3-month Phase IIa study in people with ALS demonstrated safety at dosages up to 300 mg/day and another study is currently recruiting participants with familial ALS caused by mutations in the superoxide dismutase gene. We review the rationale for testing arimoclomol in sporadic and familial ALS in the context of available safety and pharmacokinetic data. Published and unpublished literature relative to the drug in the past two decades is discussed. The current review attempts to bring together our existing understanding of the actions of arimoclomol with the disease profile of ALS. The pharmacological profile of arimoclomol and the available preclinical data make it a promising therapeutic possibility in ALS.


Asunto(s)
Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Hidroxilaminas/farmacología , Hidroxilaminas/uso terapéutico , Animales , Ensayos Clínicos como Asunto , Citoprotección/efectos de los fármacos , Aprobación de Drogas , Evaluación Preclínica de Medicamentos , Proteínas de Choque Térmico/biosíntesis , Proteínas de Choque Térmico/efectos de los fármacos , Humanos , Hidroxilaminas/efectos adversos , Hidroxilaminas/farmacocinética
7.
Muscle Nerve ; 38(1): 837-44, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18551622

RESUMEN

Arimoclomol is an investigational drug for amyotrophic lateral sclerosis (ALS) that amplifies heat shock protein gene expression during cell stress. The objectives of the present study were to assess the safety, tolerability, and pharmacokinetics of arimoclomol in ALS. Eighty-four participants with ALS received arimoclomol at one of three oral doses (25, 50, or 100 mg three times daily) or placebo. The primary outcome measure was safety and tolerability. A subset of 44 participants provided serum and cerebrospinal fluid (CSF) samples for pharmacokinetic analysis. Participants who completed 12 weeks of treatment could enroll in a 6-month open-label study. Arimoclomol at doses up to 300 mg/day was well tolerated and safe. Arimoclomol resulted in dose-linear pharmacologic exposures and the half-life did not change with continued treatment. Arimoclomol CSF levels increased with dose. Arimoclomol was shown to be safe, and it crosses the blood-brain barrier. Serum pharmacokinetic profiles support dosing of three times per day. An efficacy study in ALS is planned.


Asunto(s)
Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Hidroxilaminas/administración & dosificación , Hidroxilaminas/efectos adversos , Anciano , Esclerosis Amiotrófica Lateral/metabolismo , Barrera Hematoencefálica , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Hidroxilaminas/farmacocinética , Masculino , Persona de Mediana Edad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...