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1.
Nat Methods ; 11(11): 1177-81, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25218182

RESUMEN

For phenotypic behavior to be understood in the context of cell lineage and local environment, properties of individual cells must be measured relative to population-wide traits. However, the inability to accurately identify, track and measure thousands of single cells via high-throughput microscopy has impeded dynamic studies of cell populations. We demonstrate unique labeling of cells, driven by the heterogeneous random uptake of fluorescent nanoparticles of different emission colors. By sequentially exposing a cell population to different particles, we generated a large number of unique digital codes, which corresponded to the cell-specific number of nanoparticle-loaded vesicles and were visible within a given fluorescence channel. When three colors are used, the assay can self-generate over 17,000 individual codes identifiable using a typical fluorescence microscope. The color-codes provided immediate visualization of cell identity and allowed us to track human cells with a success rate of 78% across image frames separated by 8 h.


Asunto(s)
Rastreo Celular/métodos , Colorantes Fluorescentes , Puntos Cuánticos , Línea Celular , Humanos , Microscopía Fluorescente
2.
Fam Process ; 56(2): 518-531, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-26498111

RESUMEN

The purpose of this study was to distinguish between the influence of attachment styles and behaviors on marital quality for couples. Data were gathered from 680 couples in a married relationship. Results showed attachment style and behaviors predicted marital quality for both men and women, with higher levels of attachment related to greater quality. Attachment behaviors predicted more of the variance in quality than did styles. Specific implications regarding how therapists may wish to foster behaviors that promote attachment security in marriages are discussed.


Asunto(s)
Conducta , Relaciones Interpersonales , Matrimonio/psicología , Modelos Psicológicos , Apego a Objetos , Esposos/psicología , Adolescente , Adulto , Anciano , Comunicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Satisfacción Personal , Encuestas y Cuestionarios , Adulto Joven
3.
Cochrane Database Syst Rev ; 3: CD010360, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26930463

RESUMEN

BACKGROUND: Women with suspected early-stage ovarian cancer need surgical staging which involves taking samples from areas within the abdominal cavity and retroperitoneal lymph nodes in order to inform further treatment. One potential strategy is to surgically stage all women with suspicious ovarian masses, without any histological information during surgery. This avoids incomplete staging, but puts more women at risk of potential surgical over-treatment.A second strategy is to perform a two-stage procedure to remove the pelvic mass and subject it to paraffin sectioning, which involves formal tissue fixing with formalin and paraffin embedding, prior to ultrathin sectioning and multiple site sampling of the tumour. Surgeons may then base further surgical staging on this histology, reducing the rate of over-treatment, but conferring additional surgical and anaesthetic morbidity.A third strategy is to perform a rapid histological analysis on the ovarian mass during surgery, known as 'frozen section'. Tissues are snap frozen to allow fine tissue sections to be cut and basic histochemical staining to be performed. Surgeons can perform or avoid the full surgical staging procedure depending on the results. However, this is a relatively crude test compared to paraffin sections, which take many hours to perform. With frozen section there is therefore a risk of misdiagnosing malignancy and understaging women subsequently found to have a presumed early-stage malignancy (false negative), or overstaging women without a malignancy (false positive). Therefore it is important to evaluate the accuracy and usefulness of adding frozen section to the clinical decision-making process. OBJECTIVES: To assess the diagnostic test accuracy of frozen section (index test) to diagnose histopathological ovarian cancer in women with suspicious pelvic masses as verified by paraffin section (reference standard). SEARCH METHODS: We searched MEDLINE (January 1946 to January 2015), EMBASE (January 1980 to January 2015) and relevant Cochrane registers. SELECTION CRITERIA: Studies that used frozen section for intraoperative diagnosis of ovarian masses suspicious of malignancy, provided there was sufficient data to construct 2 x 2 tables. We excluded articles without an available English translation. DATA COLLECTION AND ANALYSIS: Authors independently assessed the methodological quality of included studies using the Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS-2) domains: patient selection, index test, reference standard, flow and timing. Data extraction converted 3 x 3 tables of per patient results presented in articles into 2 x 2 tables, for two index test thresholds. MAIN RESULTS: All studies were retrospective, and the majority reported consecutive sampling of cases. Sensitivity and specificity results were available from 38 studies involving 11,181 participants (3200 with invasive cancer, 1055 with borderline tumours and 6926 with benign tumours, determined by paraffin section as the reference standard). The median prevalence of malignancy was 29% (interquartile range (IQR) 23% to 36%, range 11% to 63%). We assessed test performance using two thresholds for the frozen section test. Firstly, we used a test threshold for frozen sections, defining positive test results as invasive cancer and negative test results as borderline and benign tumours. The average sensitivity was 90.0% (95% confidence interval (CI) 87.6% to 92.0%; with most studies typically reporting range of 71% to 100%), and average specificity was 99.5% (95% CI 99.2% to 99.7%; range 96% to 100%).Similarly, we analysed sensitivity and specificity using a second threshold for frozen section, where both invasive cancer and borderline tumours were considered test positive and benign cases were classified as negative. Average sensitivity was 96.5% (95% CI 95.5% to 97.3%; typical range 83% to 100%), and average specificity was 89.5% (95% CI 86.6% to 91.9%; typical range 58% to 99%).Results were available from the same 38 studies, including the subset of 3953 participants with a frozen section result of either borderline or invasive cancer, based on final diagnosis of malignancy. Studies with small numbers of disease-negative cases (borderline cases) had more variation in estimates of specificity. Average sensitivity was 94.0% (95% CI 92.0% to 95.5%; range 73% to 100%), and average specificity was 95.8% (95% CI 92.4% to 97.8%; typical range 81% to 100%).Our additional analyses showed that, if the frozen section showed a benign or invasive cancer, the final diagnosis would remain the same in, on average, 94% and 99% of cases, respectively.In cases where the frozen section diagnosis was a borderline tumour, on average 21% of the final diagnoses would turn out to be invasive cancer.In three studies, the same pathologist interpreted the index and reference standard tests, potentially causing bias. No studies reported blinding pathologists to index test results when reporting paraffin sections.In heterogeneity analyses, there were no statistically significant differences between studies with pathologists of different levels of expertise. AUTHORS' CONCLUSIONS: In a hypothetical population of 1000 patients (290 with cancer and 80 with a borderline tumour), if a frozen section positive test result for invasive cancer alone was used to diagnose cancer, on average 261 women would have a correct diagnosis of a cancer, and 706 women would be correctly diagnosed without a cancer. However, 4 women would be incorrectly diagnosed with a cancer (false positive), and 29 with a cancer would be missed (false negative).If a frozen section result of either an invasive cancer or a borderline tumour was used as a positive test to diagnose cancer, on average 280 women would be correctly diagnosed with a cancer and 635 would be correctly diagnosed without. However, 75 women would be incorrectly diagnosed with a cancer and 10 women with a cancer would be missed.The largest discordance is within the reporting of frozen section borderline tumours. Investigation into factors leading to discordance within centres and standardisation of criteria for reporting borderline tumours may help improve accuracy. Some centres may choose to perform surgical staging in women with frozen section diagnosis of a borderline ovarian tumour to reduce the number of false positives. In their interpretation of this review, readers should evaluate results from studies most typical of their population of patients.


Asunto(s)
Secciones por Congelación/métodos , Estadificación de Neoplasias/métodos , Neoplasias Ováricas/patología , Errores Diagnósticos/estadística & datos numéricos , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Humanos , Periodo Intraoperatorio , Neoplasias Ováricas/cirugía , Adhesión en Parafina , Neoplasias Pélvicas/patología , Estudios Retrospectivos , Sensibilidad y Especificidad
4.
Muscle Nerve ; 51(2): 214-21, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24831173

RESUMEN

INTRODUCTION: Chronic obstructive pulmonary disease (COPD) is associated with metabolic abnormalities in muscles of the lower limbs, but it is not known whether these abnormalities are generalized or limited to specific muscle groups, nor is there an easy way of predicting their presence. METHODS: Metabolism in the quadriceps and biceps of 14 COPD patients and controls was assessed during sustained contraction using 31-phosphorus magnetic resonance spectroscopy ((31) P MRS). T1 MRI was used to measure quadriceps intermuscular adipose tissue (IMAT). RESULTS: COPD patients had prolonged quadriceps phosphocreatine time (patients: 38.8 ± 12.7 s; controls: 25.2 ± 10.6 s; P = 0.006) and a lower pH (patents: 6.88 ± 0.1; controls: 6.99 ± 0.06; P = 0.002). Biceps measures were not significantly different. IMAT was associated with a nadir pH <7.0 (area under the curve = 0.84). CONCLUSIONS: Anaerobic metabolism during contraction was characteristic of quadriceps, but not biceps, muscles of patients with COPD and was associated with increased IMAT. Because IMAT can be assessed quickly by conventional MRI, it may be a useful approach for identifying patients with abnormal muscle bioenergetics.


Asunto(s)
Metabolismo Energético , Grasas/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/patología , Músculo Cuádriceps/fisiopatología , Anciano , Ejercicio Físico , Femenino , Volumen Espiratorio Forzado/fisiología , Humanos , Concentración de Iones de Hidrógeno , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Contracción Muscular/fisiología , Fosfocreatina/metabolismo , Isótopos de Fósforo , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Curva ROC , Índice de Severidad de la Enfermedad
5.
Nanotechnology ; 26(15): 155101, 2015 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-25797791

RESUMEN

The application of nanoparticles (NPs) within medicine is of great interest; their innate physicochemical characteristics provide the potential to enhance current technology, diagnostics and therapeutics. Recently a number of NP-based diagnostic and therapeutic agents have been developed for treatment of various diseases, where judicious surface functionalization is exploited to increase efficacy of administered therapeutic dose. However, quantification of heterogeneity associated with absolute dose of a nanotherapeutic (NP number), how this is trafficked across biological barriers has proven difficult to achieve. The main issue being the quantitative assessment of NP number at the spatial scale of the individual NP, data which is essential for the continued growth and development of the next generation of nanotherapeutics. Recent advances in sample preparation and the imaging fidelity of transmission electron microscopy (TEM) platforms provide information at the required spatial scale, where individual NPs can be individually identified. High spatial resolution however reduces the sample frequency and as a result dynamic biological features or processes become opaque. However, the combination of TEM data with appropriate probabilistic models provide a means to extract biophysical information that imaging alone cannot. Previously, we demonstrated that limited cell sampling via TEM can be statistically coupled to large population flow cytometry measurements to quantify exact NP dose. Here we extended this concept to link TEM measurements of NP agglomerates in cell culture media to that encapsulated within vesicles in human osteosarcoma cells. By construction and validation of a data-driven transfer function, we are able to investigate the dynamic properties of NP agglomeration through endocytosis. In particular, we statistically predict how NP agglomerates may traverse a biological barrier, detailing inter-agglomerate merging events providing the basis for predictive modelling of nanopharmacology.


Asunto(s)
Medios de Cultivo/química , Nanomedicina/métodos , Nanopartículas/química , Nanotecnología/métodos , Transporte Biológico , Línea Celular Tumoral , Simulación por Computador , Sistemas de Liberación de Medicamentos , Endocitosis , Endosomas/metabolismo , Humanos , Microscopía Electrónica de Transmisión , Modelos Estadísticos , Osteosarcoma/metabolismo , Probabilidad , Puntos Cuánticos
6.
Nat Commun ; 15(1): 4871, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38871738

RESUMEN

The phenomenon of mixed/heterogenous treatment responses to cancer therapies within an individual patient presents a challenging clinical scenario. Furthermore, the molecular basis of mixed intra-patient tumor responses remains unclear. Here, we show that patients with metastatic lung adenocarcinoma harbouring co-mutations of EGFR and TP53, are more likely to have mixed intra-patient tumor responses to EGFR tyrosine kinase inhibition (TKI), compared to those with an EGFR mutation alone. The combined presence of whole genome doubling (WGD) and TP53 co-mutations leads to increased genome instability and genomic copy number aberrations in genes implicated in EGFR TKI resistance. Using mouse models and an in vitro isogenic p53-mutant model system, we provide evidence that WGD provides diverse routes to drug resistance by increasing the probability of acquiring copy-number gains or losses relative to non-WGD cells. These data provide a molecular basis for mixed tumor responses to targeted therapy, within an individual patient, with implications for therapeutic strategies.


Asunto(s)
Inestabilidad Cromosómica , Receptores ErbB , Neoplasias Pulmonares , Mutación , Proteína p53 Supresora de Tumor , Humanos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Animales , Ratones , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Receptores ErbB/genética , Receptores ErbB/metabolismo , Receptores ErbB/antagonistas & inhibidores , Resistencia a Antineoplásicos/genética , Línea Celular Tumoral , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/patología , Terapia Molecular Dirigida/métodos , Femenino , Variaciones en el Número de Copia de ADN , Masculino
7.
Br J Radiol ; 96(1150): 20211126, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37393537

RESUMEN

In 2008, the role of clinical imaging in oncology drug development was reviewed. The review outlined where imaging was being applied and considered the diverse demands across the phases of drug development. A limited set of imaging techniques was being used, largely based on structural measures of disease evaluated using established response criteria such as response evaluation criteria in solid tumours. Beyond structure, functional tissue imaging such as dynamic contrast-enhanced MRI and metabolic measures using [18F]flourodeoxyglucose positron emission tomography were being increasingly incorporated. Specific challenges related to the implementation of imaging were outlined including standardisation of scanning across study centres and consistency of analysis and reporting. More than a decade on the needs of modern drug development are reviewed, how imaging has evolved to support new drug development demands, the potential to translate state-of-the-art methods into routine tools and what is needed to enable the effective use of this broadening clinical trial toolset. In this review, we challenge the clinical and scientific imaging community to help refine existing clinical trial methods and innovate to deliver the next generation of techniques. Strong industry-academic partnerships and pre-competitive opportunities to co-ordinate efforts will ensure imaging technologies maintain a crucial role delivering innovative medicines to treat cancer.


Asunto(s)
Neoplasias , Humanos , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones
8.
Clin Transl Sci ; 16(6): 955-965, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36808835

RESUMEN

Brain metastases (BMs) are associated with poor prognosis in epidermal growth factor receptor mutation-positive (EGFRm) non-small cell lung cancer (NSCLC). Osimertinib is a third-generation, irreversible, EGFR-tyrosine kinase inhibitor that potently and selectively inhibits EGFR-sensitizing and T790M resistance mutations with efficacy in EGFRm NSCLC including central nervous system (CNS) metastases. The open-label phase I positron emission tomography (PET) and magnetic resonance imaging (MRI) study (ODIN-BM) assessed [11 C]osimertinib brain exposure and distribution in patients with EGFRm NSCLC and BMs. Three dynamic 90-min [11 C]osimertinib PET examinations were acquired together with metabolite-corrected arterial plasma input functions at: baseline, after first oral osimertinib 80 mg dose, and after greater than or equal to 21 days of osimertinib 80 mg q.d. treatment. Contrast-enhanced MRI was performed at screening and after 25-35 days of osimertinib 80 mg q.d.; treatment effect was assessed per CNS Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and per volumetric changes in total BM using a novel analysis approach. Four patients (aged 51-77 years) completed the study. At baseline, ~1.5% injected radioactivity reached the brain (IDmax[brain] ) 22 min (median, Tmax[brain] ) after injection. Total volume of distribution (VT ) in whole brain was numerically higher compared with the BM regions. After a single oral osimertinib 80 mg dose, there was no consistent decrease in VT in whole brain or BMs. After greater than or equal to 21 days' daily treatment, VT in whole brain and BMs were numerically higher versus baseline. MRI revealed 56%-95% reduction in total BMs volume after 25-35 days of osimertinib 80 mg q.d. treatment. The [11 C]osimertinib crossed the blood-brain and brain-tumor barriers and had a high, homogeneous brain distribution in patients with EGFRm NSCLC and BMs.


Asunto(s)
Neoplasias Encefálicas , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Receptores ErbB/genética , Inhibidores de Proteínas Quinasas , Mutación , Encéfalo , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Tomografía de Emisión de Positrones , Imagen por Resonancia Magnética
9.
J Magn Reson Imaging ; 35(6): 1422-9, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22314961

RESUMEN

PURPOSE: To measure reproducibility, longitudinal and cross-sectional differences in T2* maps at 3 Tesla (T) in the articular cartilage of the knee in subjects with osteoarthritis (OA) and healthy matched controls. MATERIALS AND METHODS: MRI data and standing radiographs were acquired from 33 subjects with OA and 21 healthy controls matched for age and gender. Reproducibility was determined by two sessions in the same day, while longitudinal and cross-sectional group differences used visits at baseline, 3 and 6 months. Each visit contained symptomological assessments and an MRI session consisting of high resolution three-dimensional double-echo-steady-state (DESS) and co-registered T2* maps of the most diseased knee. A blinded reader delineated the articular cartilage on the DESS images and median T2* values were reported. RESULTS: T2* values showed an intra-visit reproducibility of 2.0% over the whole cartilage. No longitudinal effects were measured in either group over 6 months. T2* maps revealed a 5.8% longer T2* in the medial tibial cartilage and 7.6% and 6.5% shorter T2* in the patellar and lateral tibial cartilage, respectively, in OA subjects versus controls (P < 0.02). CONCLUSION: T2* mapping is a repeatable process that showed differences between the OA subject and control groups.


Asunto(s)
Cartílago Articular/patología , Articulación de la Rodilla/patología , Imagen por Resonancia Magnética/métodos , Osteoartritis de la Rodilla/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
Environ Sci Technol ; 46(6): 3085-92, 2012 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-22324637

RESUMEN

Results are presented from X-ray absorption spectroscopy based analysis of As, Cr, and V speciation within samples of bauxite ore processing residue (red mud) collected from the spill site at Ajka, Western Hungary. Cr K-edge XANES analysis found that Cr is present as Cr(3+) substituted into hematite, consistent with TEM analysis. V K-edge XANES spectra have E(1/2) position and pre-edge features consistent with the presence of V(5+) species, possibly associated with Ca-aluminosilicate phases. As K-edge XANES spectra identified As present as As(5+). EXAFS analysis reveals arsenate phases in red mud samples. When alkaline leachate from the spill site is neutralized with HCl, 94% As and 71% V are removed from solution during the formation of amorphous Al-oxyhydroxide. EXAFS analysis of As in this precipitate reveals the presence of arsenate Al-oxyhydroxide surface complexes. These results suggest that in the circumneutral pH, oxic conditions found in the Torna and Upper Marcal catchments, incorporation and sorption, respectively, will restrict the environmental mobility of Cr and As. V is inefficiently removed from solution by neutralization, therefore, the red mud may act as a source of mobile V(5+) where the red mud deposits are not removed from affected land.


Asunto(s)
Arsénico/análisis , Cromo/análisis , Residuos Industriales/análisis , Contaminantes del Suelo/análisis , Vanadio/análisis , Contaminantes Químicos del Agua/análisis , Óxido de Aluminio/química , Monitoreo del Ambiente , Industria Procesadora y de Extracción , Hungría , Microscopía Electrónica de Transmisión , Espectroscopía de Absorción de Rayos X , Difracción de Rayos X
11.
J Magn Reson Imaging ; 34(3): 702-9, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21769964

RESUMEN

PURPOSE: To combine a motion-sensitized driven equilibrium (MSDE) preparation with a multi-echo spoiled gradient-echo sequence (SPGR) to suppress the blood signal intensity in T2* mapping of carotid plaques and liver. MATERIALS AND METHODS: The analytical solution of the Bloch equations for the multi-echo SPGR sequence, with and without the MSDE preparation, was calculated to optimize sequence parameters. The sequence was implemented at 3 Tesla and T2* maps of carotid plaques and liver were first optimized for blood suppression, and then acquired from five healthy livers and six subjects with ultrasound-identified carotid plaques. RESULTS: Simulations and experimental data showed that the flip angle that gives maximal signal (Ernst angle) in the MSDE-SPGR was greatly increased from that of pure SPGR. Robust blood suppression was obtained in the T2* maps of carotid plaques and liver, requiring suppression at a field of speed (FOS) of 30 cm/s in both the carotids and liver. CONCLUSION: MSDE provides a means to suppress the blood signal intensity in SPGR sequences. Tissue T2* maps can be obtained without the confounding effects originating from blood vessels.


Asunto(s)
Artefactos , Estenosis Carotídea/sangre , Estenosis Carotídea/patología , Interpretación de Imagen Asistida por Computador/métodos , Hígado/irrigación sanguínea , Imagen por Resonancia Magnética/métodos , Técnica de Sustracción , Algoritmos , Humanos , Aumento de la Imagen/métodos , Hígado/anatomía & histología , Movimiento (Física) , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
12.
J Cereb Blood Flow Metab ; 40(4): 799-807, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31006308

RESUMEN

Osimertinib is a tyrosine kinase inhibitor (TKI) of the mutated epidermal growth factor receptor (EGFRm) with observed efficacy in patients with brain metastases. Brain exposure and drug distribution in tumor regions are important criteria for evaluation and confirmation of CNS efficacy. The aim of this PET study was therefore to determine brain distribution and exposure of 11C-labelled osimertinib administered intravenously in subjects with an intact blood-brain barrier. Eight male healthy subjects (age 52 ± 8 years) underwent one PET measurement with 11C-osimertinib. The pharmacokinetic parameters Cmax(brain) (standardized uptake value), Tmax(brain) and AUC0-90 minbrain/blood ratio were calculated. The outcome measure for 11C-osimertinib brain exposure was the total distribution volume (VT). 11C-osimertinib distributed rapidly to the brain, with higher uptake in grey than in white matter. Mean Cmax, Tmax and AUC0-90 minbrain/blood ratio were 1.5 (range 1-1.8), 13 min (range 5-30 min), and 3.8 (range 3.3-4.1). Whole brain and white matter VT were 14 mL×cm-3 (range 11-18) and 7 mL×cm-3 (range 5-12). This study in healthy volunteers shows that 11C-osimertinib penetrates the intact blood-brain barrier. The approach used further illustrates the role of molecular imaging in facilitating the development of novel drugs for the treatment of malignancies affecting the brain.


Asunto(s)
Acrilamidas/farmacocinética , Compuestos de Anilina/farmacocinética , Antineoplásicos/farmacocinética , Neoplasias Encefálicas/tratamiento farmacológico , Encéfalo/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Tomografía de Emisión de Positrones/métodos , Acrilamidas/administración & dosificación , Adulto , Compuestos de Anilina/administración & dosificación , Antineoplásicos/administración & dosificación , Barrera Hematoencefálica/metabolismo , Encéfalo/metabolismo , Neoplasias Encefálicas/secundario , Radioisótopos de Carbono , Carcinoma de Pulmón de Células no Pequeñas/patología , Voluntarios Sanos , Humanos , Inyecciones Intravenosas , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Distribución Tisular
13.
J Thorac Oncol ; 15(4): 637-648, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31887431

RESUMEN

INTRODUCTION: Osimertinib has shown promising activity in patients with leptomeningeal metastases (LMs) of EGFR-positive NSCLC at 160 mg once daily (qd) (BLOOM; NCT02228369). We report LM activity with osimertinib (80 mg qd) in a retrospective analysis of studies across the AURA program (AURA extension, AURA2, AURA17, and AURA3). METHODS: Patients with EGFR T790M-positive advanced NSCLC and progression after previous EGFR-tyrosine kinase inhibitor therapy received osimertinib (80 mg qd). Patients with central nervous system (CNS) metastases (including LMs) were eligible if the lesions were neurologically asymptomatic and stable. Patients with evidence of LMs at the study entry were retrospectively included for the analysis; brain scans were assessed for radiologic LM response by neuroradiologically blinded, independent central review per the modified Response Assessment in Neuro-Oncology LM criteria. LM objective response rate, duration of response, progression-free survival, and overall survival were assessed. A longitudinal analysis was performed to investigate the relationship between changes from the baseline in non-CNS tumor sizes and LM responses at each visit of patients in AURA LM and BLOOM studies. RESULTS: For the 22 patients included in the analysis, LM objective response rate was 55% (95% confidence interval [CI]: 32-76). Median LM duration of response was not reached (95% CI: 2.8-not calculable [NC]). Median LM progression-free survival and overall survival were 11.1 months (95% CI: 4.6-NC) and 18.8 months (95% CI: 6.3-NC), respectively. The longitudinal analysis revealed similar non-CNS and LM responses between the patients in AURA LM and BLOOM programs. CONCLUSIONS: Patients with EGFR T790M-positive NSCLC and radiologically detected LM obtained clinical benefit from osimertinib (80 mg qd).


Asunto(s)
Antineoplásicos , Neoplasias Pulmonares , Acrilamidas , Compuestos de Anilina/uso terapéutico , Antineoplásicos/uso terapéutico , Receptores ErbB/genética , Receptores ErbB/uso terapéutico , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Mutación , Inhibidores de Proteínas Quinasas/uso terapéutico , Estudios Retrospectivos
14.
J Clin Oncol ; 38(6): 538-547, 2020 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-31809241

RESUMEN

PURPOSE: In this phase I study (BLOOM), osimertinib, a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), was evaluated in patients with leptomeningeal metastases (LMs) from EGFR-mutated (EGFRm) advanced non-small-cell lung cancer (NSCLC) whose disease had progressed on previous EGFR-TKI therapy. PATIENTS AND METHODS: Patients with cytologically confirmed LM received osimertinib 160 mg once daily. Objectives were to assess confirmed objective response rate (ORR), duration of response (DoR), progression-free survival (PFS), overall survival (OS), pharmacokinetics (PK), and safety. Additional efficacy evaluations included changes from baseline in CSF cytology and neurologic examination. Measurable lesions were assessed by investigator according to RECIST version 1.1. LMs were assessed by neuroradiologic blinded central independent review (BICR) according to Response Assessment in Neuro-Oncology LM radiologic criteria and by investigator. RESULTS: Forty-one patients were enrolled. LM ORR and DoR by neuroradiologic BICR were 62% (95% CI, 45% to 78%) and 15.2 months (95% CI, 7.5 to 17.5 months), respectively. Overall, ORR by investigator was 41% (95% CI, 26% to 58%), and median DoR was 8.3 months (95% CI, 5.6 to 16.5 months). Median investigator-assessed PFS was 8.6 months (95% CI, 5.4 to 13.7 months) with 78% maturity; median OS was 11.0 months (95% CI, 8.0 to 18.0 months) with 68% maturity. CSF tumor cell clearance was confirmed in 11 (28%; 95% CI, 15% to 44%) of 40 patients. Neurologic function was improved in 12 (57%) of 21 patients with an abnormal assessment at baseline. The adverse event and PK profiles were consistent with previous reports for osimertinib. CONCLUSION: Osimertinib showed meaningful therapeutic efficacy in the CNS and a manageable safety profile at 160 mg once daily in patients with EGFRm NSCLC and LM.


Asunto(s)
Acrilamidas/uso terapéutico , Compuestos de Anilina/uso terapéutico , Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Carcinomatosis Meníngea/tratamiento farmacológico , Adulto , Anciano , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/secundario , Receptores ErbB/genética , Femenino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Masculino , Carcinomatosis Meníngea/secundario , Persona de Mediana Edad , Mutación
15.
ACS Appl Mater Interfaces ; 11(44): 41676-41687, 2019 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-31609570

RESUMEN

In wind turbine gearboxes, (near-)surface initiated fatigue is attributed to be the primary failure mechanism. In this work, the surface fatigue of a hydrogenated tungsten carbide/amorphous carbon (WC/aC:H) thin-film was tested under severe cyclic tribo-contact using polyalphaolefin (PAO) and PAO + zinc dialkyldithiophosphate (ZDDP) lubricants. The film was characterized in terms of its structure and chemistry using X-ray diffraction, analytical transmission electron microscopy, including electron energy loss spectroscopy (EELS), as well as X-ray photoelectron spectroscopy (XPS). The multilayer carbon thin-film exhibited promising surface fatigue performance showing a slight change in the hybridization state of the aC:H matrix. Dehydrogenation of the thin-film and subsequent transformation of cleaved C-H bonds to nonplanar sp2 carbon rings were inferred from EELS and XPS results. While tribo-induced changes to the aC:H matrix were not influenced by a nanometer-thick ZDDP reaction-film, the rate of oxidation of WC and its oxidation state were affected. While accelerating surface fatigue on a steel surface, the ZDDP-tribofilm protected the WC/aC:H film from surface fatigue. In contrast to the formation of polyphosphates from ZDDP molecules on steel surfaces, it appeared that on the WC/aC:H thin film surface, ZDDP molecules decompose to ZnO, suppressing the oxidative degradation of WC.

16.
Biomaterials ; 29(17): 2656-62, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18377983

RESUMEN

Ferumoxtran-10 is an ultrasmall superparamagnetic iron oxide nanoparticle potentially useful as a contrast material in magnetic resonance imaging for the diagnosis of inflammatory and degenerative disorders associated with high macrophage activity. In clinical trials, it is currently applied to monitor the effect of atorvastatin therapy on macrophage activity in human carotid plaques. A recent study reported the inhibition of iron oxide nanoparticle uptake in macrophages by lovastatin, an effect which could compromise the suitability of Ferumoxtran-10 as an MRI contrast material in patients on statin therapy. Therefore, we examined the effect of atorvastatin on human monocyte-macrophage uptake of Ferumoxtran-10 in vitro using biochemical assays, magnetic resonance imaging and transmission electron microscopy. Our study showed that non-toxic concentrations of atorvastatin did not affect the amount of Ferumoxtran-10 taken up by HMMs. Furthermore, the intracellular distribution of iron oxide nanoparticles and the resulting MRI signal intensities remained unchanged by statin treatment. These results were obtained using atorvastatin concentrations probably vastly exceeding those reached in patient plasma in vivo. Atorvastatin therapy itself is therefore unlikely to affect Ferumoxtran-10 based macrophage detection by MRI, a prerequisite for the use of this contrast material to monitor lesion macrophage burden during lipid-lowering therapy.


Asunto(s)
Ácidos Heptanoicos/farmacología , Hierro/farmacocinética , Macrófagos/efectos de los fármacos , Imagen por Resonancia Magnética/métodos , Nanopartículas/química , Óxidos/farmacocinética , Pirroles/farmacología , Atorvastatina , Células Cultivadas , Medios de Contraste/farmacocinética , Dextranos , Relación Dosis-Respuesta a Droga , Óxido Ferrosoférrico , Humanos , Hidroximetilglutaril-CoA Reductasas/farmacología , Macrófagos/metabolismo , Macrófagos/ultraestructura , Nanopartículas de Magnetita , Tamaño de la Partícula , Acetato de Tetradecanoilforbol/farmacología
17.
Magn Reson Imaging ; 26(5): 629-37, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18420368

RESUMEN

PURPOSE: The purpose of this study was to evaluate the feasibility of using proton and sodium magnetic resonance imaging (MRI) to detect fluid accumulation produced by fludrocortisone and nifedipine - two drugs known to cause salt/water retention by different mechanisms. MATERIALS AND METHODS: Twelve young healthy male subjects were randomly assigned to one of two groups and treated with either fludrocortisone or nifedipine for 14 or 25 days, respectively. The change in sodium MRI, as well as in proton T(2) value and T(1)-weighted signal intensity in the calf following postural change [referred to here as 'postural delta signal'(PDS)], was evaluated before, during and after drug administration. The changes in MRI PDS were compared to conventional physiological parameters, including body weight, calf volume and pitting edema. RESULTS: When compared to the baseline pretreatment values, the subjects treated with fludrocortisone showed a 5.5% increase in sodium MRI PDS (P=.01), a 2-ms increase in proton T(2) PDS of the gastrocnemius muscle (P=.06) and a body weight gain of 2.3% (P=.001) within 1 week. In the nifedipine-treated subjects, the sodium MRI PDS increased by 6% versus baseline (P=.03), while the proton T(2) PDS of the gastrocnemius muscle increased by 3.7 ms (P=.01), associated with a 0.5% weight gain (P=.55), within 3 weeks. No significant changes were noted in the T(1)-weighed images following postural change. Measurements of calf circumference, volume and pitting edema did not show consistent changes associated with the drug administration. CONCLUSION: The postural change in sodium MRI and proton T(2) signals provides a sensitive method for detecting the fluid accumulation produced by fludrocortisone and nifedipine. The MRI results are consistent with treatment-induced increases in extracellular fluid volume and correlate well with the observed weight gain. These findings support the potential utility of MRI for the evaluation of medication-induced fluid retention.


Asunto(s)
Líquidos Corporales/efectos de los fármacos , Fludrocortisona/farmacología , Pierna , Imagen por Resonancia Magnética/métodos , Músculo Esquelético/metabolismo , Nifedipino/farmacología , Adulto , Humanos , Masculino , Reproducibilidad de los Resultados , Sodio/farmacología
18.
Early Hum Dev ; 126: 18-22, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30241898

RESUMEN

Group B streptococcus (GBS) is the most common cause of early-onset neonatal sepsis in many countries and responsible for significant perinatal morbidity and mortality worldwide. Intrapartum antibiotic prophylaxis has been the mainstay of efforts to prevent early-onset GBS disease in recent decades, however it is unclear if women should be targeted based on the presence of clinical risk factors or by screening for GBS colonisation during pregnancy. Universal bacteriological screening of women in late pregnancy has been widely adopted but questions remain regarding its benefits and potential harms. Newer approaches to screening based on rapid point-of-care testing require further evaluation in randomised controlled trials to inform evidence-based practice. Given current preventive strategies do not protect against late onset disease and other sequelae of infection, maternal vaccination against GBS may present the best opportunity to reduce the global burden of invasive GBS disease in the future.


Asunto(s)
Tamizaje Masivo/métodos , Sepsis Neonatal/microbiología , Complicaciones Infecciosas del Embarazo/diagnóstico , Infecciones Estreptocócicas/prevención & control , Streptococcus agalactiae/patogenicidad , Antibacterianos/efectos adversos , Antibacterianos/uso terapéutico , Femenino , Humanos , Incidencia , Recién Nacido , Pruebas de Sensibilidad Microbiana , Sepsis Neonatal/prevención & control , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Factores de Riesgo , Infecciones Estreptocócicas/epidemiología
19.
J Clin Oncol ; 36(26): 2702-2709, 2018 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-30059262

RESUMEN

Purpose In patients with epidermal growth factor receptor ( EGFR) mutation-positive advanced non-small-cell lung cancer (NSCLC), there is an unmet need for EGFR-tyrosine kinase inhibitors with improved CNS penetration and activity against CNS metastases, either at initial diagnosis or time of progression. We report the first comparative evidence of osimertinib CNS efficacy versus platinum-pemetrexed from a phase III study (AURA3; ClinicalTrials.gov identifier: NCT02151981) in patients with EGFR T790M-positive advanced NSCLC who experience disease progression with prior EGFR-tyrosine kinase inhibitor treatment. Methods Patients with asymptomatic, stable CNS metastases were eligible for enrollment and were randomly assigned 2:1 to osimertinib 80 mg once daily or platinum-pemetrexed. A preplanned subgroup analysis was conducted in patients with measurable and/or nonmeasurable CNS lesions on baseline brain scan by blinded independent central neuroradiological review. The CNS evaluable for response set included only patients with one or more measurable CNS lesions. The primary objective for this analysis was CNS objective response rate (ORR). Results Of 419 patients randomly assigned to treatment, 116 had measurable and/or nonmeasurable CNS lesions, including 46 patients with measurable CNS lesions. At data cutoff (April 15, 2016), CNS ORR in patients with one or more measurable CNS lesions was 70% (21 of 30; 95% CI, 51% to 85%) with osimertinib and 31% (5 of 16; 95% CI, 11% to 59%) with platinum-pemetrexed (odds ratio, 5.13; 95% CI, 1.44 to 20.64; P = .015); the ORR was 40% (30 of 75; 95% CI, 29% to 52%) and 17% (7 of 41; 95% CI, 7% to 32%), respectively, in patients with measurable and/or nonmeasurable CNS lesions (odds ratio, 3.24; 95% CI, 1.33 to 8.81; P = .014). Median CNS duration of response in patients with measurable and/or nonmeasurable CNS lesions was 8.9 months (95% CI, 4.3 months to not calculable) for osimertinib and 5.7 months (95% CI, 4.4 to 5.7 months) for platinum-pemetrexed; median CNS progression-free survival was 11.7 months and 5.6 months, respectively (hazard ratio, 0.32; 95% CI, 0.15 to 0.69; P = .004). Conclusion Osimertinib demonstrated superior CNS efficacy versus platinum-pemetrexed in T790M-positive advanced NSCLC.


Asunto(s)
Acrilamidas/uso terapéutico , Compuestos de Anilina/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundario , Carboplatino/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/secundario , Cisplatino/uso terapéutico , Receptores ErbB/genética , Femenino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Mutación , Pemetrexed/uso terapéutico , Adulto Joven
20.
J Clin Oncol ; : JCO2018783118, 2018 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-30153097

RESUMEN

Purpose We report CNS efficacy of osimertinib versus standard epidermal growth factor receptor ( EGFR) tyrosine kinase inhibitors (TKIs) in patients with untreated EGFR-mutated advanced non-small-cell lung cancer from the phase III FLAURA study. Patients and Methods Patients (N = 556) were randomly assigned to osimertinib or standard EGFR-TKIs (gefitinib or erlotinib); brain scans were not mandated unless clinically indicated. Patients with asymptomatic or stable CNS metastases were included. In patients with symptomatic CNS metastases, neurologic status was required to be stable for ≥ 2 weeks after completion of definitive therapy and corticosteroids. A preplanned subgroup analysis with CNS progression-free survival as primary objective was conducted in patients with measurable and/or nonmeasurable CNS lesions on baseline brain scan by blinded independent central neuroradiologic review. The CNS evaluable-for-response set included patients with ≥ one measurable CNS lesion. Results Of 200 patients with available brain scans at baseline, 128 (osimertinib, n = 61; standard EGFR-TKIs, n = 67) had measurable and/or nonmeasurable CNS lesions, including 41 patients (osimertinib, n = 22; standard EGFR-TKIs, n = 19) with ≥ one measurable CNS lesion. Median CNS progression-free survival in patients with measurable and/or nonmeasurable CNS lesions was not reached with osimertinib (95% CI, 16.5 months to not calculable) and 13.9 months (95% CI, 8.3 months to not calculable) with standard EGFR-TKIs (hazard ratio, 0.48; 95% CI, 0.26 to 0.86; P = .014 [nominally statistically significant]). CNS objective response rates were 91% and 68% in patients with ≥ one measurable CNS lesion (odds ratio, 4.6; 95% CI, 0.9 to 34.9; P = .066) and 66% and 43% in patients with measurable and/or nonmeasurable CNS lesions (odds ratio, 2.5; 95% CI, 1.2 to 5.2; P = .011) treated with osimertinib and standard EGFR-TKIs, respectively. Probability of experiencing a CNS progression event was consistently lower with osimertinib versus standard EGFR-TKIs. Conclusion Osimertinib has CNS efficacy in patients with untreated EGFR-mutated non-small-cell lung cancer. These results suggest a reduced risk of CNS progression with osimertinib versus standard EGFR-TKIs.

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