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1.
JAMA Netw Open ; 1(5): e182081, 2018 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-30646153

RESUMEN

Importance: In women with locally advanced cancer of the cervix (LACC), staging defines disease extent and guides therapy. Currently, undetected disease outside the radiation field can result in undertreatment or, if disease is disseminated, overtreatment. Objective: To determine whether adding fludeoxyglucose F 18 positron emission tomography-computed tomography (PET-CT) to conventional staging with CT of the abdomen and pelvis affects therapy received in women with LACC. Design, Setting, and Participants: A randomized clinical trial was conducted. Women with newly diagnosed histologically confirmed International Federation of Gynecology and Obstetrics stage IB to IVA carcinoma of the cervix who were candidates for chemotherapy and radiation therapy (CRT) were allocated 2:1 to PET-CT plus CT of the abdomen and pelvis or CT alone. Enrollment occurred between April 2010 and June 2014 at 6 regional cancer centers in Ontario, Canada. The PET-CT scanners were at 6 associated academic institutions. The median follow-up at the time of the analysis was 3 years. The analysis was conducted on March 30, 2017. Interventions: Patients received either PET-CT plus CT of the abdomen and pelvis or CT of the abdomen and pelvis. Main Outcomes and Measures: Treatment delivered, defined as standard pelvic CRT vs more extensive CRT, ie, extended field radiotherapy or therapy with palliative intent. Results: One hundred seventy-one patients were allocated to PET-CT (n = 113) or CT (n = 58). The trial stopped early before the planned target of 288 was reached because of low recruitment. Mean (SD) age was 48.1 (11.2) years in the PET-CT group vs 48.9 (12.7) years in the CT group. In the 112 patients who received PET-CT, 68 (60.7%) received standard pelvic CRT, 38 (33.9%) more extensive CRT, and 6 (5.4%) palliative treatment. The corresponding data for the 56 patients who received CT alone were 42 (75.0%), 11 (19.6%), and 3 (5.4%). Overall, 44 patients (39.3%) in the PET-CT group received more extensive CRT or palliative treatment compared with 14 patients (25.0%) in the CT group (odds ratio, 2.05; 95% CI, 0.96-4.37; P = .06). Twenty-four patients in the PET-CT group (21.4%) received extended field radiotherapy to para-aortic nodes and 14 (12.5%) to common iliac nodes compared with 8 (14.3%) and 3 (5.4%), respectively, in the CT group (odds ratio, 1.64; 95% CI, 0.68-3.92; P = .27). Conclusions and Relevance: There was a trend for more extensive CRT with PET-CT, but the difference was not significant because the trial was underpowered. This trial provides information on the utility of PET-CT for staging in LACC. Trial Registration: ClinicalTrials.gov Identifier: NCT00895349.


Asunto(s)
Tomografía Computarizada por Tomografía de Emisión de Positrones/estadística & datos numéricos , Neoplasias del Cuello Uterino/clasificación , Adulto , Anciano , Anciano de 80 o más Años , Quimioradioterapia/métodos , Femenino , Fluorodesoxiglucosa F18/uso terapéutico , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias/métodos , Estadificación de Neoplasias/estadística & datos numéricos , Ontario/epidemiología , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Radiofármacos/uso terapéutico , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/epidemiología
2.
N Engl J Med ; 377(23): 2240-2252, 2017 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-29211671

RESUMEN

BACKGROUND: The post-thrombotic syndrome frequently develops in patients with proximal deep-vein thrombosis despite treatment with anticoagulant therapy. Pharmacomechanical catheter-directed thrombolysis (hereafter "pharmacomechanical thrombolysis") rapidly removes thrombus and is hypothesized to reduce the risk of the post-thrombotic syndrome. METHODS: We randomly assigned 692 patients with acute proximal deep-vein thrombosis to receive either anticoagulation alone (control group) or anticoagulation plus pharmacomechanical thrombolysis (catheter-mediated or device-mediated intrathrombus delivery of recombinant tissue plasminogen activator and thrombus aspiration or maceration, with or without stenting). The primary outcome was development of the post-thrombotic syndrome between 6 and 24 months of follow-up. RESULTS: Between 6 and 24 months, there was no significant between-group difference in the percentage of patients with the post-thrombotic syndrome (47% in the pharmacomechanical-thrombolysis group and 48% in the control group; risk ratio, 0.96; 95% confidence interval [CI], 0.82 to 1.11; P=0.56). Pharmacomechanical thrombolysis led to more major bleeding events within 10 days (1.7% vs. 0.3% of patients, P=0.049), but no significant difference in recurrent venous thromboembolism was seen over the 24-month follow-up period (12% in the pharmacomechanical-thrombolysis group and 8% in the control group, P=0.09). Moderate-to-severe post-thrombotic syndrome occurred in 18% of patients in the pharmacomechanical-thrombolysis group versus 24% of those in the control group (risk ratio, 0.73; 95% CI, 0.54 to 0.98; P=0.04). Severity scores for the post-thrombotic syndrome were lower in the pharmacomechanical-thrombolysis group than in the control group at 6, 12, 18, and 24 months of follow-up (P<0.01 for the comparison of the Villalta scores at each time point), but the improvement in quality of life from baseline to 24 months did not differ significantly between the treatment groups. CONCLUSIONS: Among patients with acute proximal deep-vein thrombosis, the addition of pharmacomechanical catheter-directed thrombolysis to anticoagulation did not result in a lower risk of the post-thrombotic syndrome but did result in a higher risk of major bleeding. (Funded by the National Heart, Lung, and Blood Institute and others; ATTRACT ClinicalTrials.gov number, NCT00790335 .).


Asunto(s)
Anticoagulantes/uso terapéutico , Síndrome Postrombótico/prevención & control , Terapia Trombolítica/métodos , Activador de Tejido Plasminógeno/administración & dosificación , Trombosis de la Vena/tratamiento farmacológico , Adulto , Anticoagulantes/efectos adversos , Cateterismo Periférico , Femenino , Hemorragia/etiología , Humanos , Incidencia , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Síndrome Postrombótico/epidemiología , Síndrome Postrombótico/etiología , Proteínas Recombinantes/uso terapéutico , Factores de Riesgo , Terapia Trombolítica/efectos adversos , Activador de Tejido Plasminógeno/efectos adversos , Trombosis de la Vena/complicaciones
3.
Lung Cancer ; 104: 65-69, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28213002

RESUMEN

OBJECTIVES: Following failure of a platinum-antifolate combination regimen, there is no standard therapy for advanced malignant pleural mesothelioma (MPM). The fibroblast growth factor receptor (FGFR) signaling pathways may be a relevant target in MPM. Dovitinib inhibits multiple tyrosine receptor kinases, predominantly the vascular endothelial growth factor receptors (VEGFR), but also FGFRs, and could be active in MPM. METHODS: This open-label multicentre phase II trial [NCT01769547] enrolled fit, consenting adult patients with advanced MPM who had previously received platinum-antifolate combination chemotherapy and up to one additional line of systemic therapy. Dovitinib was administered orally at 500mg/day for 5days on, 2days off, in 28-day cycles. Response was assessed every 2 cycles using RECIST 1.1 criteria modified for MPM. Correlative studies included FGFR-1 amplification on archival tumour and serum samples for circulating angiogenesis factors. The primary end-point was the proportion of patients progression-free at 3 months (PF3) using a two-stage design. RESULTS: 12 patients (10 males, median age 67) were enrolled. The median number of cycles administered was 2.5 (range 1-8). One unconfirmed partial response was observed. PF3 was 50% (95% confidence interval 28.4% to 88.0%); although the criterion for proceeding to stage II accrual was met, the trial was halted due to a combination of minimal activity with several early progression events and poor tolerability in this patient population. One of 12 tumour specimens had low amplification of FGFR-1. CONCLUSIONS: Dovitinib has minimal activity in previously-treated MPM. The role of the FGFR pathway in MPM remains unclear.


Asunto(s)
Bencimidazoles/administración & dosificación , Neoplasias Pulmonares/tratamiento farmacológico , Mesotelioma/tratamiento farmacológico , Neoplasias Pleurales/tratamiento farmacológico , Quinolonas/administración & dosificación , Receptores de Factores de Crecimiento de Fibroblastos/antagonistas & inhibidores , Receptores de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Anciano , Inductores de la Angiogénesis/sangre , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bencimidazoles/efectos adversos , Bencimidazoles/farmacología , Bencimidazoles/toxicidad , Imagen de Difusión por Resonancia Magnética/métodos , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Masculino , Mesotelioma/diagnóstico por imagen , Mesotelioma/patología , Mesotelioma Maligno , Persona de Mediana Edad , Ontario , Neoplasias Pleurales/diagnóstico por imagen , Neoplasias Pleurales/patología , Inhibidores de Proteínas Quinasas/efectos adversos , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/toxicidad , Quinolonas/efectos adversos , Quinolonas/farmacología , Quinolonas/toxicidad , Receptores de Factores de Crecimiento de Fibroblastos/uso terapéutico , Receptores de Factores de Crecimiento Endotelial Vascular/uso terapéutico
4.
Invest Ophthalmol Vis Sci ; 55(1): 424-39, 2014 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-24334447

RESUMEN

PURPOSE: To examine the pattern of cone degeneration in the retina of a transgenic mouse model of Stargartd-like dystrophy (STGD3). METHODS: Investigations were performed on ELOVL4/TG1-2 transgenic (TG) mice and wild-type (WT) littermates from 1 to 24 months of age. Phenotypes were assessed by fundus imaging, fatty acid analysis, and electroretinogram (ERG) recording. Cone degeneration pattern was determined on retina whole mounts using immunohistochemistry and Voronoi domain analyses. RESULTS: Consistent with low transgene expression, photoreceptors degenerate very slowly. At 1 month, anatomical structure and fatty acid composition of the TG retina is comparable with WT. Rod loss appears at 2 months, exhibiting a central to peripheral gradient, and fundus defects are observed at 3 months. In contrast, cone morphology, distribution and function are still normal at 12 months. Cone loss becomes apparent at 15 months when the outer nuclear layer is reduced to 3 to 4 photoreceptor rows. This process starts at the center of the retina and affects cone subtypes similarly. Very few cones remain at 24 months, after all rods have disappeared (18 months). Quantitative studies focusing on cones expressing M-opsin show a net increase in Voronoi domains and a significant decrease in regularity indexes only beyond 15 months. CONCLUSIONS: Photoreceptor degeneration in this STGD3 mouse model follows the time course of a slow rod-cone dystrophy. The cone mosaic is preserved for almost 1 year after the onset of rod loss. This long delay provides an opportunity to examine rod-cone interactions during retinal degeneration and to test therapeutic effectiveness at protracting cone dysfunction.


Asunto(s)
Degeneración Macular/congénito , Células Fotorreceptoras Retinianas Conos/patología , Animales , Western Blotting , Supervivencia Celular , Modelos Animales de Enfermedad , Electrorretinografía , Proteínas del Ojo/genética , Proteínas del Ojo/metabolismo , Estudios de Seguimiento , Inmunohistoquímica , Degeneración Macular/diagnóstico , Degeneración Macular/genética , Degeneración Macular/fisiopatología , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microscopía Fluorescente , Retina/patología , Retina/fisiopatología , Células Fotorreceptoras Retinianas Conos/metabolismo , Factores de Tiempo
5.
Biochemistry ; 45(38): 11444-52, 2006 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-16981704

RESUMEN

The conversion of the reactive center bond of the serpin alpha1-proteinase inhibitor (alpha1-PI, also known as alpha1-antitrypsin) from Met-Ser to Arg-Ser decreases the rate at which it inhibits neutrophil elastase and endows it with the ability to inhibit thrombin and activated protein C (APC). Another serpin, heparin cofactor II (HCII), contains a unique N-terminal extension that binds thrombin exosite 1. We fused residues 1-75 of HCII to the N-terminus of alpha1-PI M358R, forming an HCII-alpha1-PI chimera (HAPI M358R). It inhibited alpha-thrombin 21-fold faster than alpha1-PI M358R, with second-order rate constants of 2.3 x 10(8) M(-1) min(-1) versus 1.1 x 10(7) M(-1) min(-1), respectively. When gammaT-thrombin, which lacks an intact exosite 1, was substituted for alpha-thrombin, the kinetic advantage of HAPI M358R over alpha1-PI M358R was reduced to 9-fold, whereas APC and trypsin, proteases lacking exosite 1-like regions, were inhibited only 1.3- and 2-fold more rapidly by HAPI M358R than by alpha1-PI M358R, respectively. Maximal enhancement of alpha1-PI M358R activity required the acidic residues found between HCII residues 55 and 75, because no enhancement was observed either by fusion of residues 1-54 alone or by fusion of a mutated HCII acidic extension in which all Glu and Asp residues between positions 55 and 75 were neutralized by mutation. Fusing residues 55-75 to alpha1-PI M358R yielded a relative rate enhancement of only 6-fold, suggesting a need for the full tail region to achieve maximal enhancement. Our results suggest that transfer of the N-terminal acidic extension of HCII to alpha1-PI M358R enhanced its inhibition of thrombin by conferring the ability to bind exosite 1 on HAPI M358R. This enhancement may aid in efforts to tailor this inhibitor for therapeutic use.


Asunto(s)
Sustitución de Aminoácidos , Arginina/química , Cofactor II de Heparina/química , Cofactor II de Heparina/metabolismo , Metionina/química , Proteínas Recombinantes de Fusión/metabolismo , Trombina/antagonistas & inhibidores , alfa 1-Antitripsina/metabolismo , Fibrina/metabolismo , Humanos , Cinética , Modelos Moleculares , Desnaturalización Proteica , Solubilidad , Relación Estructura-Actividad , Termodinámica , alfa 1-Antitripsina/química
6.
Biochemistry ; 43(46): 14864-72, 2004 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-15544357

RESUMEN

The abundant plasma protein alpha(1)-proteinase inhibitor (alpha(1)-PI) physiologically inhibits neutrophil elastase (NE) and factor XIa and belongs to the serine protease inhibitor (serpin) protein superfamily. Inhibitory serpins possess a surface peptide domain called the reactive center loop (RCL), which contains the P1-P1' scissile peptide bond. Conversion of this bond in alpha(1)-PI from Met-Ser to Arg-Ser in alpha(1)-PI Pittsburgh (M358R) redirects alpha(1)-PI from inhibiting NE to inhibiting thrombin (IIa), activated protein C (APC), and other proteases. In contrast to either the wild-type or M358R alpha(1)-PI, heparin cofactor II (HCII) is a IIa-specific inhibitor with an atypical Leu-Ser reactive center. We examined the effects of replacement of all or part of the RCL of alpha(1)-PI with the corresponding parts of the HCII RCL on the activity and specificity of the resulting chimeric inhibitors. A series of 12 N-terminally His-tagged alpha(1)-PI proteins differing only in their RCL residues were expressed as soluble proteins in Escherichia coli. Substitution of the P16-P3' loop of alpha(1)-PI with that of HCII increased the low intrinsic antithrombin activity of alpha(1)-PI to near that of heparin-free HCII, while analogous substitution of the P2'-P3' dipeptide surpassed this level. However, gel-based complexing and quantitative kinetic assays showed that all mutant proteins inhibited thrombin at less than 2% of the rate of alpha(1)-PI (M358R) unless the P1 residue was also mutated to Arg. An alpha(1)-PI (P16-P3' HCII/M358R) variant was only 3-fold less active than M358R against IIa but 70-fold less active against APC. The reduction in anti-APC activity is desired in an antithrombotic agent, but the improvement in inhibitory profile came at the cost of a 3.5-fold increase in the stoichiometry of inhibition. Our results suggest that, while P1 Arg is essential for maximal antithrombin activity in engineered alpha(1)-PI proteins, substitution of the corresponding HCII residues can enhance thrombin specificity.


Asunto(s)
Arginina/química , Cofactor II de Heparina/genética , Trombina/antagonistas & inhibidores , alfa 1-Antitripsina/química , alfa 1-Antitripsina/genética , Secuencia de Aminoácidos , Sustitución de Aminoácidos/genética , Línea Celular Tumoral , Humanos , Radioisótopos de Yodo/metabolismo , Cinética , Datos de Secuencia Molecular , Mutagénesis Insercional , Proteína C/antagonistas & inhibidores , Proteína C/metabolismo , Estructura Secundaria de Proteína/genética , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Trombina/química , Trombina/metabolismo , alfa 1-Antitripsina/biosíntesis
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