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1.
Int J Toxicol ; 43(3): 231-242, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38327194

RESUMEN

During drug discovery, small molecules are typically assayed in vitro for secondary pharmacology effects, which include ion channels relevant to cardiac electrophysiology. Compound A was an irreversible inhibitor of myeloperoxidase investigated for the treatment of peripheral artery disease. Oral doses in dogs at ≥5 mg/kg resulted in cardiac arrhythmias in a dose-dependent manner (at Cmax, free ≥1.53 µM) that progressed in severity with time. Nevertheless, a panel of 13 different cardiac ion channel (K, Na, and Ca) assays, including hERG, failed to identify pharmacologic risks of the molecule. Compound A and a related Compound B were evaluated for electrophysiological effects in the isolated rabbit ventricular wedge assay. Compounds A and B prolonged QT and Tp-e intervals at ≥1 and ≥.3 µM, respectively, and both prolonged QRS at ≥5 µM. Compound A produced early after depolarizations and premature ventricular complexes at ≥5 µM. These data indicate both compounds may be modulating hERG (Ikr) and Nav1.5 ion channels. In human IPSC cardiomyocytes, Compounds A and B prolonged field potential duration at ≥3 µM and induced cellular dysrhythmia at ≥10 and ≥3 µM, respectively. In a rat toxicology study, heart tissue: plasma concentration ratios for Compound A were ≥19X at 24 hours post-dose, indicating significant tissue distribution. In conclusion, in vitro ion channel assays may not always identify cardiovascular electrophysiological risks observed in vivo, which can be affected by tissue drug distribution. Risk for arrhythmia may increase with a "trappable" ion channel inhibitor, particularly if cardiac tissue drug levels achieve a critical threshold for pharmacologic effects.


Asunto(s)
Arritmias Cardíacas , Células Madre Pluripotentes Inducidas , Miocitos Cardíacos , Animales , Miocitos Cardíacos/efectos de los fármacos , Perros , Humanos , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Conejos , Arritmias Cardíacas/inducido químicamente , Masculino , Ventrículos Cardíacos/efectos de los fármacos , Canales Iónicos/metabolismo , Femenino
3.
Eur J Nucl Med Mol Imaging ; 51(4): 1085-1096, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37982850

RESUMEN

Glioma are clinically challenging tumors due to their location and invasiveness nature, which often hinder complete surgical resection. The evaluation of the isocitrate dehydrogenase mutation status has become crucial for effective patient stratification. Through a transdisciplinary approach, we have developed an 18F-labeled ligand for non-invasive assessment of the IDH1R132H variant by using positron emission tomography (PET) imaging. In this study, we have successfully prepared diastereomerically pure [18F]AG-120 by copper-mediated radiofluorination of the stannyl precursor 6 on a TRACERlab FX2 N radiosynthesis module. In vitro internalization studies demonstrated significantly higher uptake of [18F]AG-120 in U251 human high-grade glioma cells with stable overexpression of mutant IDH1 (IDH1R132H) compared to their wild-type IDH1 counterpart (0.4 vs. 0.013% applied dose/µg protein at 120 min). In vivo studies conducted in mice, exhibited the excellent metabolic stability of [18F]AG-120, with parent fractions of 85% and 91% in plasma and brain at 30 min p.i., respectively. Dynamic PET studies with [18F]AG-120 in naïve mice and orthotopic glioma rat model reveal limited blood-brain barrier permeation along with a low uptake in the brain tumor. Interestingly, there was no significant difference in uptake between mutant IDH1R132H and wild-type IDH1 tumors (tumor-to-blood ratio[40-60 min]: ~1.7 vs. ~1.3). In conclusion, our preclinical evaluation demonstrated a target-specific internalization of [18F]AG-120 in vitro, a high metabolic stability in vivo in mice, and a slightly higher accumulation of activity in IDH1R132H-glioma compared to IDH1-glioma. Overall, our findings contribute to advancing the field of molecular imaging and encourage the evaluation of [18F]AG-120 to improve diagnosis and management of glioma and other IDH1R132H-related tumors.


Asunto(s)
Neoplasias Encefálicas , Glioma , Glicina/análogos & derivados , Piridinas , Humanos , Ratones , Ratas , Animales , Isocitrato Deshidrogenasa/genética , Glioma/genética , Tomografía de Emisión de Positrones/métodos , Neoplasias Encefálicas/genética
4.
Molecules ; 27(12)2022 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-35744895

RESUMEN

Isocitrate dehydrogenases (IDHs) are metabolic enzymes commonly mutated in human cancers (glioma, acute myeloid leukaemia, chondrosarcoma, and intrahepatic cholangiocarcinoma). These mutated variants of IDH (mIDH) acquire a neomorphic activity, namely, conversion of α-ketoglutarate to the oncometabolite D-2-hydroxyglutarate involved in tumourigenesis. Thus, mIDHs have emerged as highly promising therapeutic targets, and several mIDH specific inhibitors have been developed. However, the evaluation of mIDH status, currently performed by biopsy, is essential for patient stratification and thus treatment and follow-up. We report herein the development of new radioiodinated and radiofluorinated analogues of olutasidenib (FT-2102) as tools for noninvasive single photon emission computed tomography (SPECT) or positron emission tomography (PET) imaging of mIDH1 up- and dysregulation in tumours. Nonradiolabelled derivatives 2 and 3 halogenated at position 6 of the quinolinone scaffold were synthesised and tested in vitro for their inhibitory potencies and selectivities in comparison with the lead compound FT-2102. Using a common organotin precursor, (S)-[125I]2 and (S)-[18F]3 were efficiently synthesised by radio-iododemetallation and copper-mediated radiofluorination, respectively. Both radiotracers were stable at room temperature in saline or DPBS solution and at 37 °C in mouse serum, allowing future planning of their in vitro and in vivo evaluations in glioma and chondrosarcoma models.


Asunto(s)
Neoplasias de los Conductos Biliares , Neoplasias Óseas , Condrosarcoma , Glioma , Leucemia Mieloide Aguda , Animales , Conductos Biliares Intrahepáticos , Condrosarcoma/diagnóstico por imagen , Condrosarcoma/genética , Glioma/diagnóstico por imagen , Glioma/genética , Humanos , Ratones , Mutación , Tomografía de Emisión de Positrones , Piridinas , Quinolinas , Tomografía Computarizada de Emisión de Fotón Único
5.
Acad Med ; 96(9): 1263-1267, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-33735126

RESUMEN

The announcement of the closure of Philadelphia's Hahnemann University Hospital in June 2019 sent shock waves through the academic community. The closure had a devastating impact on the residents and fellows who trained there, the patients who had long received their care there, and faculty and staff who had provided care there for decades. Since its beginnings, the hospital, established as part of Hahnemann Medical College in 1885, was a major site for medical student education. The authors share the planning before and actions during the crisis that protected the educational experiences of third- and fourth-year medical students at Drexel University College of Medicine assigned to Hahnemann University Hospital. The lessons they learned can be helpful to leadership in academic health systems in the United States facing a diminishing number of clinical training sites for medical and other health professions students, a situation that is likely to worsen as the COVID-19 pandemic continues to weaken the health care ecosystem.


Asunto(s)
Educación de Pregrado en Medicina/organización & administración , Clausura de las Instituciones de Salud/métodos , Hospitales Universitarios/organización & administración , Educación de Pregrado en Medicina/métodos , Docentes Médicos/organización & administración , Docentes Médicos/psicología , Humanos , Relaciones Interprofesionales , Philadelphia , Estudiantes de Medicina/psicología
6.
Invest New Drugs ; 39(2): 295-303, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32948981

RESUMEN

Currently, there is no gold standard treatment for Extraskeletal Myxoid Chondrosarcomas (EMC) making wide margin surgical resection the most effective alternative treatment. Nevertheless, in previous preclinical studies our lab demonstrated the potential of the hypoxia-activated prodrug (HAP) ICF05016 on EMC murine model inoculated with the H-EMC-SS human cell line. The aim of this study was to assess, in vivo, the relevance of the combination of this HAP with External Beam Radiotherapy (EBR). Firstly EMC-bearing mice were treated with 6 Gy or 12 Gy of EBR (single 6 MV photon). Then for combination of HAP and EBR, animals received 6 doses of ICF05016 (46.8 µmol/kg, intravenously) at 4-day intervals, with 6 Gy EBR performed 24 h after the 3rd dose of HAP. Animals were monitored throughout the study for clinical observations (tumour growth, side effects) and survival studies were performed. From tumour samples, PCNA, Ki-67 and p21 expressions were used as markers of proliferation and cell cycle arrest. Statistical significances were determined using Kruskall-Wallis and log rank tests. The radiosensitivity of the EMC model was demonstrated at 12 Gy with significant inhibition of tumour growth. Then, the HAP strategy potentiated EBR efficacy at a lower dose (6 Gy) by improving survival without generating side effects. Thus, results of this study showed the potential interest of ICF05016 for the combination with EBR in the management of EMC.


Asunto(s)
Quimioradioterapia/métodos , Condrosarcoma/terapia , Imidazoles/administración & dosificación , Neoplasias de los Tejidos Conjuntivo y Blando/terapia , Profármacos/administración & dosificación , Animales , Línea Celular , Quimioradioterapia/efectos adversos , Condrosarcoma/mortalidad , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones , Ratones SCID , Neoplasias de los Tejidos Conjuntivo y Blando/mortalidad , Dosis de Radiación , Carga Tumoral
7.
Bioorg Chem ; 98: 103747, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32208207

RESUMEN

The tumor microenvironment in chondrosarcoma (CHS), a chemo- and radio-resistant cancer provides unique hallmarks for developing a chondrosarcoma targeted drug-delivery system. Tumor targeting could be achieved using a quaternary ammonium function (QA) as a ligand for aggrecan, the main high negative charged proteoglycan of the extracellular matrix of CHS, and a 2-nitroimidazole as trigger that enables hypoxia-responsive drug release. In a previous work, ICF05016 was identified as efficient proteoglycan-targeting hypoxia-activated prodrug in a human extraskeletal myxoid chondrosarcoma model in mice and a first study of the structure-activity relationship of the QA function and the alkyl linker length was conducted. Here, we report the second part of the study, namely the modification of the nitro-aromatic trigger and the position of the proteoglycan-targeting ligand at the aromatic ring as well as the nature of the alkylating mustard. Synthetic approaches have been established to functionalize the 2-nitroimidazole ring at the N-1 and C-4 positions with a terminal tertiary alkyl amine, and to perform the phosphorylation step namely through the use of an amine borane complex, leading to phosphoramide and isophosphoramide mustards and also to a phosphoramide mustard bearing four 2-chloroethyl chains. In a preliminary study using a reductive chemical activation, QA-conjugates, except the 4-nitrobenzyl one, were showed to undergo efficient cleavage with release of the corresponding mustard. However N,N,N-trimethylpropylaminium tethered to the N-1 or C-4 positions of the imidazole seemed to hamper the enzymatic reduction of the prodrugs and all tested compounds featured moderate selectivity toward hypoxic cells, likely not sufficient for application as hypoxia-activated prodrugs.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Óseas/tratamiento farmacológico , Condrosarcoma/tratamiento farmacológico , Diseño de Fármacos , Neoplasias de los Tejidos Conjuntivo y Blando/tratamiento farmacológico , Mostazas de Fosforamida/farmacología , Profármacos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Neoplasias Óseas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Condrosarcoma/patología , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Neoplasias de los Tejidos Conjuntivo y Blando/patología , Mostazas de Fosforamida/síntesis química , Mostazas de Fosforamida/química , Profármacos/síntesis química , Profármacos/química , Relación Estructura-Actividad
8.
Acad Med ; 95(9S A Snapshot of Medical Student Education in the United States and Canada: Reports From 145 Schools): S422-S425, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33626735
9.
Eur J Med Chem ; 158: 51-67, 2018 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-30199705

RESUMEN

Due to an abundant chondrogenic, poorly vascularized and particularly hypoxic extracellular matrix, chondrosarcoma, a malignant cartilaginous tumour, is chemo- and radio-resistant. Surgical resection with wide margins remains the mainstay of treatment. To address the lack of therapy, our strategy aims to increase anticancer drugs targeting and delivery in the tumour, by leveraging specific chondrosarcoma hallmarks: an extensive cartilaginous extracellular matrix, namely the high negative fixed charge density and severe chronic hypoxia. A dual targeted therapy for chondrosarcoma was investigated by conjugation of a hypoxia-activated prodrug (HAP) to quaternary ammonium (QA) functions which exhibit a high affinity for polyanionic sites of proteoglycans (PGs), the major components of the chondrosarcoma extracellular matrix. Based on preclinical results, an imidazole prodrug, ICF05016, was identified and provided the basis for a lead optimization study. A series of 27 QA-phosphoramide mustard conjugates, differing by the type of QA function and the length of the alkyl linker, was yielded by a common multi-step sequence involving phosphorylation of a key 2-nitroimidazole alcohol. Then, a screening was realized by surface plasmon resonance technology to assess biomolecular interactions between QA derivatives and aggrecan, the most abundant PG in chondrosarcoma. Results revealed that affinity depends more on the type of QA function, than on the linker length. Moreover, the presence of a benzyl group enhanced affinity to aggrecan. Twelve compounds were shortlisted and evaluated for antiproliferative activity (i.e., growth inhibiting concentration 50), under normoxic and hypoxic conditions using the human extraskeletal myeloid chondrosarcoma cell line (HEMC-SS). For all prodrugs, hypoxic selectivity was maintained and even increased, compared with the lead. From this study, compound 31f emerged as the most effective PG-targeted HAPs with a dissociation constant of 2.10 µM in the SPR experiment, a hypoxia cytotoxicity ratio of 24 and an efficient reductive cleavage under chemical and enzymatic conditions.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Óseas/tratamiento farmacológico , Condrosarcoma/tratamiento farmacológico , Profármacos/farmacología , Proteoglicanos/metabolismo , Compuestos de Amonio Cuaternario/farmacología , Agrecanos/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Condrosarcoma/metabolismo , Condrosarcoma/patología , Humanos , Terapia Molecular Dirigida , Oxígeno/metabolismo , Profármacos/química , Profármacos/metabolismo , Compuestos de Amonio Cuaternario/química , Compuestos de Amonio Cuaternario/metabolismo , Relación Estructura-Actividad , Hipoxia Tumoral/efectos de los fármacos
10.
Oncotarget ; 8(56): 95824-95840, 2017 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-29221170

RESUMEN

Due to its abundant chondrogenic matrix and hypoxic tissue, chondrosarcoma is chemo- and radio-resistant. Our group has developed a proteoglycan targeting strategy by using a quaternary ammonium (QA) function as a carrier of DNA alkylating agents to chondrosarcoma environment. Here, we assessed the relevance of this strategy applied to hypoxia-activated prodrugs, by conjugating a QA to 2-nitroimidazole phosphoramidate. This derivative, named as 8-QA, was evaluated respectively to its non-QA equivalent and to a QA-conjugated but non-hypoxia activated. Firstly binding to aggrecan was confirmed from dissociation constant determined by Surface Plasmon Resonance. In vitro, in HEMC-SS chondrosarcoma cells cultured in monolayer and in spheroids, 8-QA showed higher cytotoxic activity in hypoxia versus normoxia, and led to a strong accumulation of cells in S phase and apoptosis. In vivo, a HEMC-SS xenograft model was implanted on SCID mice and characterized for hypoxia by photoacoustic imaging as well as proteoglycan content. When HEMC-SS bearing mice were given 8-QA at 47 µmol/kg according to a q4d x 6 schedule, a significant 62.1% inhibition of tumor growth was observed, without associated hematological side effects. Mechanistic studies of treated tumors highlighted decrease in mitotic index associated to increase in both p21 and p53S15 markers. Interestingly, 8-QA treatment induced an increase of DNA damages as measured by γH2AX predominantly found in pimonidazole-positive hypoxic areas. These preclinical results are the first to demonstrate the interest of addressing hypoxia-activated prodrugs selectively to proteoglycan of chondrogenic tumor tissue, as a promising therapeutic strategy.

11.
Bioorg Med Chem ; 25(20): 5692-5708, 2017 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-28927903

RESUMEN

Nitrogen mustards, such as chlorambucil (CLB), can cause adverse side-effects due to ubiquitous distribution in non-target organs. To minimize this toxicity, strategies of tumor-targeting drug delivery have been developed, where a cytotoxic warhead is linked to a tumor-cell-specific small ligand. Malignant cells exhibit marked glucose avidity and an accelerated metabolism by aerobic glycolysis, known as the Warburg effect, and recognized as a hallmark of cancer. A targeting approach exploiting the Warburg effect by conjugation of CLB to 2-fluoro-2-deoxyglucose (FDG) was previously reported and identified two peracetylated glucoconjugates 2 and 3 with promising antitumor activities in vivo. These results prompted us to investigate the importance of the spacer in this tumor-targeting glucose-based conjugates. Here we report the chemical synthesis and an in vitro cytotoxicity evaluation, using a 5-member panel of human tumor cell lines and human fibroblasts, of 16 new CLB glucoconjugates in which the alkylating drug is attached to the C-1 position of FDG via different linkages. We studied the structure-activity relationships in the linker, and evidenced the positive impact of an aromatic linker on in vitro cytotoxicity: compound 51 proved to be the most active FDG-CLB glucoside, characterized by a bis-aromatic spacer tethered to CLB through an amide function.


Asunto(s)
Antígenos de Neoplasias , Clorambucilo/química , Sistemas de Liberación de Medicamentos , Fluorodesoxiglucosa F18/química , Fluorodesoxiglucosa F18/farmacología , Antígenos de Neoplasias/química , Antineoplásicos Alquilantes/química , Antineoplásicos Alquilantes/farmacología , Antineoplásicos Alquilantes/toxicidad , Línea Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular , Clorambucilo/síntesis química , Clorambucilo/farmacología , Fluorodesoxiglucosa F18/síntesis química , Fluorodesoxiglucosa F18/toxicidad , Humanos , Concentración 50 Inhibidora , Estructura Molecular , Relación Estructura-Actividad
12.
Mol Cancer Ther ; 15(11): 2575-2585, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27573424

RESUMEN

To date, surgery remains the only option for the treatment of chondrosarcoma, which is radio- and chemoresistant due in part to its large extracellular matrix (ECM) and poor vascularity. In case of unresectable locally advanced or metastatic diseases with a poor prognosis, improving the management of chondrosarcoma still remains a challenge. Our team developed an attractive approach of improvement of the therapeutic index of chemotherapy by targeting proteoglycan (PG)-rich tissues using a quaternary ammonium (QA) function conjugated to melphalan (Mel). First of all, we demonstrated the crucial role of the QA carrier for binding to aggrecan by surface plasmon resonance. In the orthotopic model of Swarm rat chondrosarcoma, an in vivo biodistribution study of Mel and its QA derivative (Mel-QA), radiolabeled with tritium, showed rapid radioactivity accumulation in healthy cartilaginous tissues and tumor after [3H]-Mel-QA injection. The higher T/M ratio of the QA derivative suggests some advantage of QA-active targeting of chondrosarcoma. The antitumoral effects were characterized by tumor volume assessment, in vivo 99mTc-NTP 15-5 scintigraphic imaging of PGs, 1H-HRMAS NMR spectroscopy, and histology. The conjugation of a QA function to Mel did not hamper its in vivo efficiency and strongly improved the tolerability of Mel leading to a significant decrease of side effects (hematologic analyses and body weight monitoring). Thus, QA conjugation leads to a significant improvement of the therapeutic index, which is essential in oncology and enable repeated cycles of chemotherapy in patients with chondrosarcoma. Mol Cancer Ther; 15(11); 2575-85. ©2016 AACR.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Óseas/metabolismo , Condrosarcoma/metabolismo , Proteoglicanos/metabolismo , Animales , Neoplasias Óseas/diagnóstico , Neoplasias Óseas/tratamiento farmacológico , Línea Celular Tumoral , Condrosarcoma/diagnóstico , Condrosarcoma/tratamiento farmacológico , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Humanos , Masculino , Melfalán/química , Melfalán/farmacología , Imagen Molecular/métodos , Imagen Óptica/métodos , Compuestos de Amonio Cuaternario/química , Ratas
13.
Invest New Drugs ; 30(4): 1782-90, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21499733

RESUMEN

Cartilage tumours present ongoing therapeutic challenges due to their chondrogenic extracellular matrix that potentially hampers drug delivery, their low percentage of dividing cells, and their poor vascularity. In this context, and based on the affinity of the quaternary ammonium moiety for proteoglycans (PG), we developed a strategy that uses the quaternary ammonium function to selectively deliver DNA alkylating agents to the cartilage tumour tissue. We engineered the quaternary ammonium derivative of melphalan (Mel-AQ) and assessed its antitumoural activity in vitro and in vivo. In vitro, micromolar concentrations of Mel-AQ inhibited the proliferation of human HEMC-SS chondrosarcoma and Saos-2 osteosarcoma cell lines. Moreover, 24-h incubation with 20 µM Mel-AQ induced a 2.5-fold increase in S population and a 1.5-fold increase in subG0G1 population compared to controls. In vivo, Mel-AQ demonstrated antitumour activity in the orthotopic model of primary Swarm rat chondrosarcoma. When given to chondrosarcoma-bearing rats (three doses of 16 µmol/kg at days 8, 12 and 16 post-implant), Mel-AQ demonstrated an optimal antitumour effect at day 43, when tumour cell growth inhibition peaked at 69%. Interestingly, the treatment protocol was proved well tolerated, since the animals showed no weight loss over the course of the study. This antitumoural effect was assessed in vivo by scintigraphic imaging using (99m)Tc-NTP 15-5 developed in our lab as a PG-targeting radiotracer, and tumour tissue was analyzed at study-end by biochemical PG assay with Alcian blue staining. Mel-AQ treatment led to a significant decrease in the PG content of tumoural tissue. These experimental results highlighted the promising antitumour potential of Mel-AQ as a PG-targeting strategy for therapeutic management of chondrosarcoma.


Asunto(s)
Antineoplásicos Alquilantes/uso terapéutico , Condrosarcoma/tratamiento farmacológico , Melfalán/análogos & derivados , Compuestos de Amonio Cuaternario/uso terapéutico , Animales , Antineoplásicos Alquilantes/farmacología , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/patología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Condrosarcoma/patología , Ensayos de Selección de Medicamentos Antitumorales , Compuestos Heterocíclicos con 1 Anillo , Humanos , Masculino , Melfalán/química , Melfalán/farmacología , Melfalán/uso terapéutico , Proteoglicanos/metabolismo , Compuestos de Amonio Cuaternario/química , Compuestos de Amonio Cuaternario/farmacología , Ratas , Ratas Sprague-Dawley
14.
Eur J Med Chem ; 46(11): 5705-10, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21924528

RESUMEN

The proteasome is a promising target in cancer therapy. However, it is ubiquitous and its inhibitors cause side effects. To target melanoma cells we synthesized new peptide aldehyde and vinylsulfone inhibitors of the proteasome conjugated to the melanin-targeting ligand (MTL) derived from radiotracer [(123)I]-N-(2-diethylaminoethyl)benzamide ([(123)I]BZA) or [(125)I]-N-(4-dipropylaminobutyl)-4-iodobenzamide ([(125)I]BZ18). Influence on the cytotoxicity of the benzamide alkyl side chain length and the composition of the amino acid sequence was assessed. Among the conjugates evaluated, compound 16 and 22 presented the highest cytotoxicity (IC(50), 0.71 and 0.64 µM respectively), which persisted in the presence of an MTL derived from N-(dialkylaminoalkylenyl)benzamide residue.


Asunto(s)
Aldehídos/farmacología , Antineoplásicos/farmacología , Melanoma/tratamiento farmacológico , Terapia Molecular Dirigida , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasoma , Sulfonas/farmacología , Aldehídos/química , Aldehídos/metabolismo , Aldehídos/uso terapéutico , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Diseño de Fármacos , Humanos , Concentración 50 Inhibidora , Ligandos , Melaninas/metabolismo , Melanoma/patología , Inhibidores de Proteasas/química , Inhibidores de Proteasas/metabolismo , Inhibidores de Proteasas/uso terapéutico , Sulfonas/química , Sulfonas/metabolismo , Sulfonas/uso terapéutico
15.
Invest New Drugs ; 29(3): 424-33, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20033262

RESUMEN

Our strategy is to increase drug accumulation in target tumour cells using specific "vectors" tailored to neoplastic tissue characteristics, which ideally are not found in healthy tissues. The aim of this work was to use 2-fluoro-2-deoxyglucose (FDG) as a drug carrier, in view of its well-known accumulation by most primary and disseminated human tumours. We had previously selected two FDG-cytotoxic conjugates of chlorambucil (CLB), i.e. compounds 21a and 40a, on the basis of their in vitro profiles. Here we investigated the antitumour profile and tolerance of these compounds in vitro and in vivo in two murine cell lines of solid tumours. In vitro, we found that micromolar concentrations of compounds 21a and 40a inhibited proliferation of B16F0 and CT-26 cell lines. Interestingly, compounds 21a and 40a were found to act at different levels in the cell cycle: S and subG1 accumulation for 21a and G2 accumulation for 40a. In vivo, a single-dose-finding study to select the Maximum Tolerated Dose (MTD) by the intraperitoneal route (IP) showed that the two peracetylated glucoconjugates of CLB were less toxic than CLB itself. When given to tumour-bearing mice (melanoma and colon carcinoma models), according to a "q4d × 3" schedule (i.e., three doses at 4-day intervals) both compounds demonstrated a promising antitumour activity, with Log Cell Kill (LCK) values higher than 1.3 in both B16F0 and CT-26 models. Hence compounds 21a and 40a are good candidates for further works to develop new highly active antineoplastic compounds.


Asunto(s)
Antineoplásicos Alquilantes/efectos adversos , Antineoplásicos Alquilantes/farmacología , Clorambucilo/efectos adversos , Clorambucilo/farmacología , Fluorodesoxiglucosa F18/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto , Animales , Antineoplásicos Alquilantes/química , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Clorambucilo/química , Humanos , Dosis Máxima Tolerada , Ratones
16.
Ann Intern Med ; 153(2): 121-5, 2010 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-20643992

RESUMEN

Few patients read their doctors' notes, despite having the legal right to do so. As information technology makes medical records more accessible and society calls for greater transparency, patients' interest in reading their doctors' notes may increase. Inviting patients to review these notes could improve understanding of their health, foster productive communication, stimulate shared decision making, and ultimately lead to better outcomes. Yet, easy access to doctors' notes could have negative consequences, such as confusing or worrying patients and complicating rather than improving patient-doctor communication. To gain evidence about the feasibility, benefits, and harms of providing patients ready access to electronic doctors' notes, a team of physicians and nurses have embarked on a demonstration and evaluation of a project called OpenNotes. The authors describe the intervention and share what they learned from conversations with doctors and patients during the planning stages. The team anticipates that "open notes" will spread and suggests that over time, if drafted collaboratively and signed by both doctors and patients, they might evolve to become contracts for care.


Asunto(s)
Sistemas de Registros Médicos Computarizados , Acceso de los Pacientes a los Registros , Relaciones Médico-Paciente , Médicos de Familia , Comunicación , Estudios de Factibilidad , Humanos , Sistemas de Registros Médicos Computarizados/organización & administración , Satisfacción del Paciente , Médicos de Familia/organización & administración , Carga de Trabajo
17.
J Gen Intern Med ; 24(5): 636-41, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19259748

RESUMEN

BACKGROUND: The field of hospital medicine is growing rapidly in academic medical centers. However, few organizations have explicitly considered the opportunities and barriers posed to hospital medicine's development as an academic field in internal medicine. OBJECTIVE: To develop consensus around key areas limiting or facilitating hospital medicine's development as an academic discipline. DESIGN: Consensus format conference of key stakeholders in academic hospital medicine. RESULTS: The Consensus Group identified several issues impeding the development of academic hospital medicine as a recognized entity in academic settings, including extraordinarily rapid growth, increasingly preponderate non-teaching roles, and demands to perform non-clinical duties (such as quality improvement) not generally viewed as academic pursuits. The Consensus Group developed recommendations for addressing these concerns, specifically 1) characterizing the 'optimal' job description for an academic hospitalist, 2) developing better local and at-a-distance opportunities for training academic hospitalists in key aspects of early career success, 3) advocacy for development of fellows and junior faculty researchers in hospital medicine. Fostering academic hospital medicine will help address these issues more effectively and will help the field while also attracting the next generation of generalists needed to care for an increasingly complex inpatient population.


Asunto(s)
Centros Médicos Académicos/normas , Centros Médicos Académicos/tendencias , Médicos Hospitalarios/normas , Médicos Hospitalarios/tendencias , Humanos
18.
J Hosp Med ; 4(4): 240-6, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19260044

RESUMEN

BACKGROUND: The field of hospital medicine is growing rapidly in academic medical centers. However, few organizations have explicitly considered the opportunities for and barriers to hospital medicine's development as an academic field in internal medicine. OBJECTIVE: The objective was to develop consensus around key areas limiting or facilitating hospital medicine's development as an academic discipline. DESIGN: The design was a consensus format conference of key stakeholders in academic hospital medicine. RESULTS: The consensus group identified several issues impeding the development of academic hospital medicine as a recognized entity in academic settings, including extraordinarily rapid growth, increasingly preponderant nonteaching roles, and demands to perform nonclinical duties (such as quality improvement) not generally viewed as academic pursuits. The consensus group developed recommendations for addressing these concerns, specifically: 1) characterizing the optimal job description for an academic hospitalist, 2) developing better local and at-a-distance opportunities for training academic hospitalists in key aspects of early career success, and 3) advocating for the development of fellows and junior faculty researchers in hospital medicine. SUMMARY: Fostering academic hospital medicine will help address these issues more effectively and will help the field while also attracting the next generation of generalists needed to care for an increasingly complex inpatient population.


Asunto(s)
Centros Médicos Académicos/organización & administración , Centros Médicos Académicos/normas , Hospitales/normas , Personal de Hospital/normas , Perfil Laboral/normas
19.
J Gen Intern Med ; 23(4): 379-82, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18373133

RESUMEN

INTRODUCTION: Type 2 diabetes is one of the nation's most prevalent chronic diseases. Although well-known practice guidelines exist, real-life clinical performance often falls short of benchmarks. AIM: Employ an electronic registry derived from a fully integrated electronic health record (EHR) as the cornerstone of an intervention to improve compliance with recommended diabetes performance measures in an integrated practice network. SETTING: Geisinger Health System's network of 38 practice sites providing care to over 20,000 persons with diabetes located in a 40-county region of central and northeastern Pennsylvania. PROGRAM DESCRIPTION: A multidisciplinary group of physicians worked to create a "bundle" of best practice measures for diabetes. This measurement tool was then used as part of a multifaceted intervention to improve physician performance in diabetes care, including audit and feedback, computerized reminders, and financial incentives. Changes in performance of individual measures and the total "bundle" were tracked monthly over 1 year. PROGRAM EVALUATION: Significant increases were seen in all measures of diabetes care over the 12-month period of the study. Vaccination for pneumococcal disease and influenza improved from 56.5% to 80.8% (p < .0001) and 55.1% to 71.0% (p < .0001), respectively. The percentage of patients with ideal glucose control (HBA1c < 7.0) increased from 32.2% to 34.8% (p < .001), and blood pressure control (<130/80) improved from 39.7% to 43.9% (p < .0001). The overall number of patients receiving all 9 "bundled" measurements improved from 2.4% to 6.5% (p < .0001). DISCUSSION: Diabetes care improved significantly in response to a multifaceted intervention featuring the use of an EHR-derived registry in an integrated delivery system. More work is needed to demonstrate that such improvements will translate into improved patient health outcomes.


Asunto(s)
Sistemas de Apoyo a Decisiones Clínicas , Complicaciones de la Diabetes/prevención & control , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Sistemas de Entrada de Órdenes Médicas , Sistemas de Registros Médicos Computarizados/estadística & datos numéricos , Anciano , Sistemas de Información en Atención Ambulatoria , Prestación Integrada de Atención de Salud , Femenino , Humanos , Masculino , Persona de Mediana Edad , Servicio Ambulatorio en Hospital , Cooperación del Paciente , Pennsylvania , Médicos , Pautas de la Práctica en Medicina , Garantía de la Calidad de Atención de Salud , Sistemas Recordatorios
20.
J Gen Intern Med ; 23(4): 399-404, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18373136

RESUMEN

BACKGROUND: Falls are the leading cause of injury-related deaths in the aging population. Electronic medical record (EMR) systems can identify at-risk patients and enable interventions to decrease risk factors for falls. OBJECTIVE: The objectives of this study were to evaluate an EMR-based intervention to reduce overall medication use, psychoactive medication use, and occurrence of falls in an ambulatory elderly population at risk for falls. DESIGN: Prospective, randomized by clinic site. PATIENTS/PARTICIPANTS: Six-hundred twenty community-dwelling patients over 70 at risk for falls based on age and medication use. INTERVENTIONS: A standardized medication review was conducted and recommendations made to the primary physician via the EMR. MEASUREMENTS AND MAIN RESULTS: Patients were contacted to obtain self reports of falls at 3-month intervals over the 15-month period of study. Fall-related diagnoses and medication data were collected through the EMR. A combination of descriptive analyses and multivariate regression models were used to evaluate differences between the 2 groups, adjusting for baseline medication patterns and comorbidities. Although the intervention did not reduce the total number of medications, there was a significant negative relationship between the intervention and the total number of medications started during the intervention period (p < .01, regression estimate -0.199) and the total number of psychoactive medications (p < .05, regression estimate -0.204.) The impact on falls was mixed; with the intervention group 0.38 times as likely to have had 1 or more fall-related diagnosis (p < .01); when data on self-reported falls was included, a nonsignificant reduction in fall risk was seen. CONCLUSIONS: The current study suggests that using an EMR to assess medication use in the elderly may reduce the use of psychoactive medications and falls in a community-dwelling elderly population.


Asunto(s)
Accidentes por Caídas/prevención & control , Sistemas de Apoyo a Decisiones Clínicas , Sistemas de Registros Médicos Computarizados , Polifarmacia , Psicotrópicos/efectos adversos , Sistemas Recordatorios , Anciano , Actitud hacia los Computadores , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Servicios de Salud para Ancianos , Humanos , Masculino , Auditoría Médica , Servicio Ambulatorio en Hospital , Pennsylvania , Médicos de Familia , Pautas de la Práctica en Medicina , Factores de Riesgo , Población Rural
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