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1.
Eur Radiol ; 27(2): 526-535, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27277261

RESUMEN

OBJECTIVES: Our study sought to compare the overall survival in patients with hepatocellular carcinoma (HCC) and portal venous thrombosis (PVT), treated with either conventional trans-arterial chemoembolization (cTACE) or drug-eluting beads (DEB) TACE. METHODS: This retrospective analysis included a total of 133 patients, treated without cross-over and compared head-to-head by means or propensity score weighting. Mortality was compared using survival analysis upon propensity score weighting. Adverse events and liver toxicity grade ≥3 were recorded and reported for each TACE. In order to compare with historical sorafenib studies, a sub-group analysis was performed and included patients who fulfilled the SHARP inclusion criteria. RESULTS: The median overall survival (MOS) of the entire cohort was 4.53 months (95 % CI, 3.63-6.03). MOS was similar across treatment arms, no significant difference between cTACE (N = 95) and DEB-TACE (N = 38) was observed (MOS of 5.0 vs. 3.33 months, respectively; p = 0.157). The most common adverse events after cTACE and DEB- TACE, respectively, were as follows: post-embolization syndrome [N = 57 (30.0 %) and N = 38 (61.3 %)], diarrhea [N = 3 (1.6 %) and N = 3 (4.8 %)], and encephalopathy [N = 11 (5.8 %) and N = 2 (3.2 %)]. CONCLUSION: Our retrospective study could not reveal a difference in toxicity and efficiency between cTACE and DEB-TACE for treatment of advanced stage HCC with PVT. KEY POINTS: • Conventional TACE (cTACE) and drug-eluting-beads TACE (DEB-TACE) demonstrated equal safety profiles. • Survival rates after TACE are similar to patients treated with sorafenib. • Child-Pugh class and tumor burden are reliable predictors of survival.


Asunto(s)
Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/métodos , Neoplasias Hepáticas/terapia , Vena Porta , Trombosis de la Vena/complicaciones , Anciano , Antineoplásicos/administración & dosificación , Carcinoma Hepatocelular/complicaciones , Femenino , Humanos , Neoplasias Hepáticas/complicaciones , Masculino , Persona de Mediana Edad , Niacinamida/administración & dosificación , Niacinamida/análogos & derivados , Compuestos de Fenilurea/administración & dosificación , Estudios Retrospectivos , Sorafenib , Análisis de Supervivencia , Tasa de Supervivencia , Resultado del Tratamiento
2.
J Vasc Interv Radiol ; 26(12): 1751-60, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26525118

RESUMEN

PURPOSE: To review the safety of hepatic radioembolization (RE) in patients with high (≥ 10%) hepatopulmonary shunt fraction (HPSF) using various prophylactic techniques. MATERIALS AND METHODS: A review was conducted of 409 patients who underwent technetium 99m-labeled macroaggregated albumin scintigraphy before planned RE. Estimated pulmonary absorbed radiation doses based on scintigraphy and hepatic administered activity were calculated. Outcomes from dose reductions and adjunctive catheter-based prophylactic techniques used to reduce lung exposure were assessed. RESULTS: There were 80 patients with HPSF ≥ 10% who received RE treatment (41 resin microspheres for metastases, 39 glass microspheres for hepatocellular carcinoma). Resin microspheres were used in 17 patients according to consensus guideline-recommended dose reduction; 38 patients received no dose reduction because the expected lung dose was < 30 Gy. Prophylactic techniques were used in 25 patients (with expected lung dose ≤ 74 Gy), including hepatic vein balloon occlusion, variceal embolization, or bland arterial embolization before, during, or after RE delivery. Repeated scintigraphy after prophylactic techniques to reduce HPSF in seven patients demonstrated a median change of -40% (range, +32 to -69%). Delayed pneumonitis developed in two patients, possibly related to radiation recall after chemoembolization. Response was lower in patients treated with resin spheres with dose reduction, with an objective response rate of 13% and disease control rate of 47% compared with 56% and 94%, respectively, without dose reduction (P = .023, P = .006). CONCLUSIONS: Dose reduction recommendations for HPSF may compromise efficacy. Excessive shunting can be reduced by prophylactic catheter-based techniques, which may improve the safety of performing RE in patients with high HPSF.


Asunto(s)
Síndrome Hepatopulmonar/epidemiología , Síndrome Hepatopulmonar/prevención & control , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/prevención & control , Traumatismos por Radiación/epidemiología , Traumatismos por Radiación/prevención & control , California/epidemiología , Comorbilidad , Extravasación de Materiales Terapéuticos y Diagnósticos/epidemiología , Extravasación de Materiales Terapéuticos y Diagnósticos/prevención & control , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Radiofármacos/uso terapéutico , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento , Radioisótopos de Itrio/administración & dosificación , Radioisótopos de Itrio/uso terapéutico
3.
JCO Precis Oncol ; 8: e2300349, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38237098

RESUMEN

PURPOSE: Cancer patients with advanced-stage disease have poor prognosis, typically having limited options for efficacious treatment, and genomics-based therapy guidance continues to benefit only a fraction of patients. Next-generation ex vivo approaches, such as cell mass-based response testing (MRT), offer an alternative precision medicine approach for a broader population of patients with cancer, but validation of clinical feasibility and potential impact remain necessary. MATERIALS AND METHODS: We evaluated the clinical feasibility and accuracy of using live-cell MRT to predict patient drug sensitivity. Using a unified measurement workflow with a 48-hour result turnaround time, samples were subjected to MRT after treatment with a panel of drugs in vitro. After completion of therapeutic course, clinical response data were correlated with MRT-based predictions of outcome. Specimens were collected from 104 patients with solid (n = 69) and hematologic (n = 35) malignancies, using tissue formats including needle biopsies, malignant fluids, bone marrow aspirates, and blood samples. Of the 81 (78%) specimens qualified for MRT, 41 (51%) patients receiving physician-selected therapies had treatments matched to MRT. RESULTS: MRT demonstrated high concordance with clinical responses with an odds ratio (OR) of 14.80 (P = .0003 [95% CI, 2.83 to 102.9]). This performance held for both solid and hematologic malignances with ORs of 20.67 (P = .0128 [95% CI, 1.45 to 1,375.57]) and 8.20 (P = .045 [95% CI, 0.77 to 133.56]), respectively. Overall, these results had a predictive accuracy of 80% (P = .0026 [95% CI, 65 to 91]). CONCLUSION: MRT showed highly significant correlation with clinical response to therapy. Routine clinical use is technically feasible and broadly applicable to a wide range of samples and malignancy types, supporting the need for future validation studies.


Asunto(s)
Neoplasias Hematológicas , Neoplasias , Humanos , Neoplasias/tratamiento farmacológico
4.
Front Oncol ; 13: 916196, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37007151

RESUMEN

Introduction: Circulating tumor-derived biomarkers can potentially impact cancer management throughout the continuum of care. This small exploratory study aimed to assess the relative levels of such biomarkers in the tumor-draining vascular beds in patients with solid tumors compared to levels in their peripheral veins. Methods: Using an endovascular image-guided approach, we obtained blood samples from peripheral veins and other vascular compartments-including the most proximal venous drainage from solid tumors-from a set of nine oncology patients with various primary and metastatic malignancies. We then interrogated these samples for a panel of oncological biomarkers, including circulating tumor cells (CTCs), exosome-derived microRNAs (miRNAs), circulating tumor DNA (ctDNA) mutations, and certain cancer-related proteins/biochemical markers. Results: We found substantially higher levels of CTCs, certain miRNAs, and specific ctDNA mutations in samples from vascular beds closer to the tumor compared with those from peripheral veins and also noted that some of these signals were altered by treatment procedures. Discussion: Our results indicate that tumor-proximal venous samples are highly enriched for some oncological biomarkers and may allow for more robust molecular analysis than peripheral vein samples.

5.
Cancer Treat Res Commun ; 33: 100626, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36041372

RESUMEN

Small pulmonary nodules (≤1.5 cm) are frequently detected on routine chest imaging and lung cancer screening studies. Our goal was to determine the clinical value of CT-guided core needle biopsy (CNB) in the evaluation of such nodules. In this single-center study, we retrospectively analyzed patient data (n = 44) for CNBs on lung nodules (≤1.5 cm) performed at our biopsy center between May 2017 and March 2020. We analyzed for the rate of pathology diagnosis, molecular/biomarker analysis, complications, and change in clinical management and outcome over a period ranging up to 60 months after biopsy. A pathology diagnosis of malignancy or benign lesion was obtained in 97.9% of biopsies in this cohort. The rate of complications was low with only 6.8% of patients requiring the insertion of a temporary small profile interventional radiology (IR) pigtail chest tube for pneumothorax. Out of the subset of biopsy specimens that were sent for tissue molecular analysis, 90% had enough tissue preserved after initial pathological analysis to obtain at least one molecular marker. Our data show that CT-guided CNB is safe and reliable, and should be considered for the evaluation of small, suspicious lung nodules found on routine screenings for the early detection and evaluation of malignant lesions.


Asunto(s)
Detección Precoz del Cáncer , Neoplasias Pulmonares , Humanos , Estudios Retrospectivos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Biopsia Guiada por Imagen/efectos adversos , Biopsia Guiada por Imagen/métodos , Tomografía Computarizada por Rayos X , Pulmón/diagnóstico por imagen , Pulmón/patología
6.
Commun Biol ; 5(1): 1295, 2022 11 26.
Artículo en Inglés | MEDLINE | ID: mdl-36435843

RESUMEN

Functional precision medicine offers a promising complement to genomics-based cancer therapy guidance by testing drug efficacy directly on a patient's tumor cells. Here, we describe a workflow that utilizes single-cell mass measurements with inline brightfield imaging and machine-learning based image classification to broaden the clinical utility of such functional testing for cancer. Using these image-curated mass measurements, we characterize mass response signals for 60 different drugs with various mechanisms of action across twelve different cell types, demonstrating an improved ability to detect response for several slow acting drugs as compared with standard cell viability assays. Furthermore, we use this workflow to assess drug responses for various primary tumor specimen formats including blood, bone marrow, fine needle aspirates (FNA), and malignant fluids, all with reports generated within two days and with results consistent with patient clinical responses. The combination of high-resolution measurement, broad drug and malignancy applicability, and rapid return of results offered by this workflow suggests that it is well-suited to performing clinically relevant functional assessment of cancer drug response.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Neoplasias/tratamiento farmacológico , Recuento de Células , Flujo de Trabajo , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico
8.
Pediatr Radiol ; 41(10): 1250-8, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21553038

RESUMEN

BACKGROUND: Clinical application efforts for the hepatocyte-specific MRI contrast agent gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) have mainly been directed toward detection and characterization of various hepatic masses in the adult population. OBJECTIVE: Here we report our initial experience with Gd-EOB-DTPA for evaluating congenital and acquired hepatobiliary pathologies in the pediatric population. MATERIALS AND METHODS: Twenty-one consecutive children receiving Gd-EOB-DTPA for functional hepatobiliary evaluation at our institution were retrospectively identified with IRB approval. The use of Gd-EOB-DTPA was classified in each case as definite, potential, or no clinical utility, focusing on the clinical value gained beyond traditional noncontrast fluid-sensitive MR cholangiopancreatography (FS-MRCP) and other imaging modalities. RESULTS: Definite added value of Gd-EOB-DTPA was found in 12 patients, with potential value in 4 patients, and no value in 5 patients. Benefit was seen in cases of iatrogenic and non-iatrogenic biliary strictures, perihepatic fluid collections for biliary leak, hepatobiliary dysfunction in the absence of hyperbilirubinemia, and in the functional exclusion of cystic duct occlusion that can be seen in acute cholecystitis. CONCLUSION: This is the first reported series of children with Gd-EOB-DTPA and this early work suggests potential pediatric applications.


Asunto(s)
Enfermedades de las Vías Biliares/diagnóstico , Pancreatocolangiografía por Resonancia Magnética/métodos , Hepatopatías/diagnóstico , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Niño , Preescolar , Medios de Contraste , Femenino , Gadolinio DTPA , Humanos , Lactante , Masculino , Estudios Retrospectivos
10.
AJR Am J Roentgenol ; 195(3): 687-91, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20729447

RESUMEN

OBJECTIVE: The purpose of our study was to evaluate image quality in a 3D spoiled gradient-recalled echo (SPGR) sequence that was modified to incorporate respiratory navigation to limit the deleterious effects of respiratory motion and to compare it with conventional scanning during breath-holding and free breathing. CONCLUSION: Respiratory navigation of 3D SPGR sequences is technically feasible, and image quality is modestly improved over free breathing acquisitions using conventional 3D SPGR sequences. This may represent a promising imaging alternative for patients who cannot hold their breath.


Asunto(s)
Imagenología Tridimensional , Hepatopatías/diagnóstico , Imagen por Resonancia Magnética/métodos , Respiración , Adulto , Medios de Contraste , Femenino , Gadolinio DTPA , Humanos , Masculino , Persona de Mediana Edad , Estadísticas no Paramétricas
11.
Mol Endocrinol ; 22(7): 1552-64, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18451095

RESUMEN

Estrogens, acting through the estrogen receptors (ERs), play crucial roles in regulating the function of reproductive and other systems under physiological and pathological conditions. ER activity in regulating target genes is modulated by the binding of both steroidal and synthetic nonsteroidal ligands, with ligand binding inducing ERs to adopt various conformations that control their interactions with transcriptional coregulators. Previously, we developed an intramolecular folding sensor with a mutant form of ERalpha (ER(G521T)) that proved to be essentially unresponsive to the endogenous ligand 17beta-estradiol, yet responded very well to certain synthetic ligands. In this study, we have characterized this G521T-ER mutation in terms of the potency and efficacy of receptor response toward several steroidal and nonsteroidal ligands in two different ways: directly, by ligand effects on mutant ER conformation (by the split-luciferase complementation system), and indirectly, by ligand effects on mutant ER transactivation. Full-length G521T-ER shows no affinity for estradiol and does not activate an estrogen-responsive reporter gene. The synthetic pyrazole agonist ligand propyl-pyrazole-triol is approximately 100-fold more potent than estradiol in inducing intramolecular folding and reporter gene transactivation with the mutant ER, whereas both ligands have high potency on wild-type ER. This estradiol-unresponsive mutant ER can also specifically highlight the agonistic property of the selective ER modulator, 4-hydroxytamoxifen, by reporter gene transactivation, even in the presence of estradiol, and it can exert a dominant-negative effect on estrogen-stimulated wild-type ER. This system provides a model for ER-mutants that show differential ligand responsiveness to gene activation to gain insight into the phenomenon of hormone resistance observed in endocrine therapies of ER-positive breast cancers.


Asunto(s)
Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Mutación , Animales , Relación Dosis-Respuesta a Droga , Estradiol/metabolismo , Estrógenos/química , Humanos , Ligandos , Modelos Biológicos , Conformación Molecular , Unión Proteica , Pirazoles/química , Receptores de Estrógenos/metabolismo , Esteroides/metabolismo , Activación Transcripcional
13.
Pain Pract ; 7(4): 332-6, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17986157

RESUMEN

We describe an incidental finding of intradural lumbar disc herniation diagnosed radiographically during discography. A patient was referred to our center for discography with symptoms of worsening, intractable low back pain radiating to both hips and the left leg which was exacerbated when standing and walking. Magnetic resonance imaging of the lumbar spine revealed multiple disc bulges and lumbar facet arthroses with ligamentum flavum hypertrophy producing moderate central canal and lateral recess stenosis. Discography was performed at three levels (L3-4, L4-5, L5-S1). During fluoroscopically guided injection into L4-5 it was noted that contrast was not contained within the disc and spread intrathecally with a myelographic appearance. Computerized tomography confirmed accurate needle placement and a spread of contrast into the intrathecal space. To the best of our knowledge, this is the first report describing a finding of intradural disc herniation while performing discography. Physicians should be aware of this potential finding while performing this technique.


Asunto(s)
Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Desplazamiento del Disco Intervertebral/patología , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/patología , Mielografía , Medios de Contraste/farmacocinética , Fluoroscopía , Humanos , Dolor de la Región Lumbar/diagnóstico por imagen , Dolor de la Región Lumbar/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios , Tomografía Computarizada por Rayos X
14.
J Am Coll Radiol ; 14(9): 1144-1150, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28623048

RESUMEN

BACKGROUND: To determine the impact, if any, of the 2010 FDA safety communication on the rate of inferior vena cava filter (IVCF) placement over time. METHODS: The Nationwide Inpatient Sample was interrogated for the most recent years preceding and after the FDA safety communication-from 2005 to 2014. IVCF placements and associated diagnoses were identified using corresponding International Classification of Diseases, version nine codes. Trends in number of IVCF placement were evaluated in aggregate and by associated diagnoses, both of which were further stratified by hospital geographic cluster, hospital teaching status, and patient demographics. Generalized linear regression models were used to determine statistical significance of trends over time. RESULTS: IVCF placements steadily increased between 2005 and 2010 (100,434 in 2005 versus 129,614 in 2010, growth rate 5.81%). Aggregate IVCF placements subsequently declined between 2010 and 2014 (96,005 in 2014, decline rate -6.48%). IVCF placements peaked in 2010, the year of the FDA advisory. The proportion of filter placements for therapeutic indication of venous thromboembolism increased significantly during the study period (69.8% in 2005 versus 80.4% in 2014, P < .001). Neither trend varied significantly by patient demographics or hospital characteristics. CONCLUSIONS: IVCF placements have declined significantly since 2010, when the FDA advisory was released. The proportion of IVCFs placed in patients with venous thromboembolism, as opposed to prophylactic indications, is increasing.


Asunto(s)
Vigilancia de Productos Comercializados , Filtros de Vena Cava/estadística & datos numéricos , Humanos , Modelos Lineales , Estados Unidos , United States Food and Drug Administration , Filtros de Vena Cava/tendencias , Tromboembolia Venosa/prevención & control
15.
Mol Endocrinol ; 19(6): 1516-28, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15661830

RESUMEN

The direct regulation of gene transcription by nuclear receptors, such as the estrogen receptor (ER), involves not just ligand and DNA binding but the recruitment of coregulators. Typically, recruitment of p160 coactivator proteins to agonist-liganded ER is considered to be unidirectional, with ligand binding stabilizing an ER ligand binding domain (LBD) conformation that favors coactivator interaction. Using fluorophore-labeled ERalpha-LBDs, we present evidence for a pronounced stabilization of ER conformation that results from coactivator binding, manifest by decreased ER sensitivity to proteases and reduced conformational dynamics, as well as for the formation of a novel coactivator-stabilized (costabilized) receptor conformation, that can be conveniently monitored by the generation of an excimer emission from pyrene-labeled ERalpha-LBDs. This costabilized conformation may embody features required to support ER transcriptional activity. Different classes of coactivator proteins combine with estrogen agonists of different structure to elicit varying degrees of this receptor stabilization, and antagonists and coactivator binding inhibitors disfavor the costabilized conformation. Remarkably, high concentrations of coactivators engender this conformation even in apo- and antagonist-bound ERs (more so with selective ER modulators than with pure antagonists), providing an in vitro model for the development of resistance to hormone therapy in breast cancer.


Asunto(s)
Biofisica/métodos , Receptores de Estrógenos/química , Sitio Alostérico , Animales , Anisotropía , Neoplasias de la Mama/tratamiento farmacológico , ADN/química , ADN/metabolismo , Dimerización , Resistencia a Antineoplásicos , Receptor alfa de Estrógeno/metabolismo , Transferencia Resonante de Energía de Fluorescencia , Humanos , Técnicas In Vitro , Ligandos , Microscopía Fluorescente , Modelos Químicos , Modelos Moleculares , Péptido Hidrolasas/metabolismo , Péptidos/química , Unión Proteica , Conformación Proteica , Estructura Terciaria de Proteína , Receptores de Estrógenos/metabolismo , Espectrometría de Fluorescencia , Relación Estructura-Actividad , Tamoxifeno/farmacología , Factores de Tiempo , Transcripción Genética , Tripsina/farmacología
16.
Cardiovasc Intervent Radiol ; 39(4): 538-46, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26486152

RESUMEN

PURPOSE: To evaluate the feasibility, risks, and techniques of percutaneous removal of permanent TrapEase and Simon Nitinol IVC filters. MATERIALS AND METHODS: Between August 2011 and August 2015, 12 patients (5 women, 7 men; age range, 26-75 years) underwent an attempt at percutaneous removal of permanent TrapEase (10) and Simon Nitinol (2) IVC filters due to a history of IVC filter complications or need for lifelong anticoagulation due to the filter. Medical records were reviewed for filter dwell time, presence of iliocaval deep venous thrombosis, procedural technique, and complications. RESULTS: Filter dwell times ranged from 7 days to 15 years (mean 5.1 years). Successful removal of permanent IVC filters was possible in 11 of 12 patients (91.6%). In 1 patient, a chronically thrombosed IVC filter could not be removed despite laser sheath assistance, but was successfully recanalized with the PowerWire RF guidewire. In the failed retrieval attempt, a stent was placed through the chronically thrombosed IVC filter with restoration of in-line flow. One major complication of large venous groin hematoma was encountered. CONCLUSIONS: In carefully selected patients, percutaneous removal of permanent IVC filters can be performed safely despite prolonged filter dwell times. Extraction of chronically embedded permanent IVC filters may be facilitated by jugular and femoral approaches, often with laser sheath assistance. Chronic filter thrombosis and caval scarring may increase the risk of retrieval failure.


Asunto(s)
Remoción de Dispositivos/métodos , Filtros de Vena Cava/efectos adversos , Vena Cava Inferior/cirugía , Tromboembolia Venosa/prevención & control , Adulto , Anciano , Remoción de Dispositivos/instrumentación , Femenino , Humanos , Masculino , Persona de Mediana Edad
17.
Reg Anesth Pain Med ; 41(3): 398-401, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27035463

RESUMEN

BACKGROUND: Perioperative management of patients on anticoagulant therapy prior to interventional pain procedures creates a challenge when balancing the risk of bleeding against thromboembolic events. CASE REPORT: We report a case of epidural hematoma formation in the cervical spine following interlaminar epidural steroid injection in an elderly woman with chronic neck and arm pain, who was on clopidogrel therapy. CONCLUSIONS: This is the first reported case of hematoma formation immediately following an epidural steroid injection possibly associated with clopidogrel, even though established guidelines on the timing of the discontinuation of clopidogrel prior to the procedure were exceeded. Severe pain appears to be the first symptom of hematoma formation, and therefore immediate diagnostic workup and evacuation of hematoma are essential in preventing neurological damage. It may be advisable to carry out a test specific for clopidogrel such as the P2Y12 to ensure that there is no residual action on platelet aggregation function, particularly in patients who may be slow metabolizers of clopidogrel. Caution is advised prior to administering analgesics with antiplatelet effects such as ketorolac.


Asunto(s)
Betametasona/administración & dosificación , Dolor Crónico/tratamiento farmacológico , Glucocorticoides/administración & dosificación , Hematoma Espinal Epidural/inducido químicamente , Dolor de Cuello/tratamiento farmacológico , Inhibidores de Agregación Plaquetaria/efectos adversos , Ticlopidina/análogos & derivados , Enfermedad Aguda , Anciano de 80 o más Años , Vértebras Cervicales , Dolor Crónico/diagnóstico , Clopidogrel , Descompresión Quirúrgica , Esquema de Medicación , Femenino , Hematoma Espinal Epidural/diagnóstico , Hematoma Espinal Epidural/cirugía , Humanos , Inyecciones Epidurales/efectos adversos , Laminectomía , Imagen por Resonancia Magnética , Dolor de Cuello/diagnóstico , Inhibidores de Agregación Plaquetaria/administración & dosificación , Factores de Riesgo , Ticlopidina/administración & dosificación , Ticlopidina/efectos adversos
18.
Mol Endocrinol ; 17(12): 2593-602, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12947047

RESUMEN

The ligand-induced conformation of a nuclear receptor ligand-binding domain (LBD) is a principal factor leading to transcriptional activity and determining the pharmacological response. Using the estrogen receptor (ER) LBD-labeled site specifically with a fluorophore, we demonstrate that effects of ligand binding on the conformation and dynamics of this domain can be studied directly, in a quantitative and convenient fashion, by various fluorescence methods. Estrogen ligands of different pharmacological character-agonists, selective ER modulators (SERMs), and pure antagonists-each produce distinctive spectroscopic signatures, characteristic of the conformational or dynamic features of their ER-LBD complexes. We can directly follow the equilibrium of helix 12 positions through the degree of local fluorophore rotational freedom and receptor helicity near the C terminus of helix 11. We observe differences even between ligands within a specific pharmacological class, such as the SERMs raloxifene and trans-4-hydroxytamoxifen, highlighting the ability of these fluorescent receptor sensors to detect unique ER conformations induced even by closely related ligands, yet ones that produce distinctive biological activities in estrogen target cells. Fluorophore-labeled LBDs can serve as versatile molecular sensors predictive of ligand pharmacological character and should be broadly applicable to other members of the nuclear receptor superfamily.


Asunto(s)
Receptores de Estrógenos/química , Receptores de Estrógenos/metabolismo , Sitios de Unión , Dimerización , Receptor alfa de Estrógeno , Polarización de Fluorescencia , Cinética , Ligandos , Modelos Moleculares , Conformación Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
19.
Mol Endocrinol ; 16(12): 2706-19, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12456792

RESUMEN

Nuclear receptors form strong dimers that are essential for their function as transcription factors, and it is thought that ligand binding can affect dimer stability. In this report, we describe convenient fluorescence resonance energy transfer (FRET)-based methods for measuring the thermodynamic and kinetic stability of dimers of the estrogen receptor-alpha ligand-binding domain (ERalpha-LBD). We have developed receptors that are chemically labeled with a single fluorophore in a site-specific manner. These fluorophore-labeled ERs are functional and can be used to measure directly the affinity and stability of ERalpha-LBD dimers. Our results indicate that unliganded ERalpha-LBDs exist as very stable dimers and that the dissociation rate of these dimers is slow (t(1/2)=39 +/- 3 min at 28 C) and is further slowed (< or =7-fold) by the addition of various ligands. Estrogen antagonists provide greater kinetic stabilization of the ER dimers than agonists. In addition, coactivator peptides containing the LXXLL motif selectively stabilize agonist-bound ERalpha-LBD dimers. These fluorescence-based assays for measuring the kinetic and thermodynamic stability of ER dimers provide a functional in vitro method for assessing the agonist or antagonist character of novel ligands.


Asunto(s)
Dimerización , Receptores de Estrógenos/química , Receptores de Estrógenos/metabolismo , Sitios de Unión , Cisteína/química , Estabilidad de Medicamentos , Transferencia de Energía , Estradiol/metabolismo , Antagonistas de Estrógenos/química , Antagonistas de Estrógenos/metabolismo , Antagonistas de Estrógenos/farmacología , Receptor alfa de Estrógeno , Estrógenos/química , Estrógenos/metabolismo , Colorantes Fluorescentes , Histona Acetiltransferasas , Humanos , Cinética , Ligandos , Modelos Moleculares , Estructura Molecular , Mutagénesis Sitio-Dirigida , Coactivador 1 de Receptor Nuclear , Unión Proteica , Espectrometría de Fluorescencia , Relación Estructura-Actividad , Termodinámica , Factores de Transcripción/farmacología , Tritio
20.
Cardiovasc Intervent Radiol ; 38(4): 1036-42, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25613669

RESUMEN

Biological sealants are being increasingly used in a variety of surgical specialties for their hemostatic and sealing capabilities. However, their use in interventional radiology has not been widely reported. The authors describe a case of duodenal perforation occurring after 15 years of gastric bypass surgery, in whom surgical diversion was unsuccessfully attempted and the leakage was successfully controlled using percutaneous administration of a combination of biological and organic sealants.


Asunto(s)
Enfermedades Duodenales/diagnóstico por imagen , Enfermedades Duodenales/terapia , Adhesivo de Tejido de Fibrina/uso terapéutico , Fístula Intestinal/diagnóstico por imagen , Fístula Intestinal/terapia , Radiología Intervencionista , Duodeno/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Resultado del Tratamiento
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