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1.
Oncologist ; 26(2): e251-e260, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32864832

RESUMEN

BACKGROUND: Recent revision significantly changed the American Joint Committee on Cancer (AJCC) staging criteria for differentiated thyroid cancer (DTC). To quantitatively evaluate resulting changes in patient stage distribution and the associated disease-specific survival (DSS) incorporating diverse populations, we performed a meta-analysis of studies comparing the AJCC 7th edition (AJCC-7) with 8th edition (AJCC-8) staging for DTC. MATERIALS AND METHODS: After PROSPERO registration (#CRD42019123657), publications in English reporting DSS of DTC with AJCC-7 and AJCC-8 from inception to June 2019 were identified by search of MEDLINE and PubMed. Random-effects meta-analyses were conducted to compare differences in survival between AJCC-7 and AJCC-8. Pooled hazard ratios, 10-year DSS, and corresponding interval estimates were calculated for AJCC subgroups. Differences in survival between editions were assessed using subgroup analysis with nonoverlapping confidence intervals indicating statistical significance. RESULTS: Final analysis included six studies with 10,850 subjects and median follow-up from 55 to 148 months. Use of AJCC-8 shifted classification to earlier stages: stage I, from 60% to 81%; stage II, from 5% to 13%; stage III, from 21% to 2%; stage IV, from 10% to 3%. Ten-year DSS was significantly lower in AJCC-8 versus AJCC-7 in patients with stage II (88.6%, 95% confidence interval [CI] 82.7-94.6% vs. 98.1%, 95% CI 96.6-99.6%, respectively) and stage III disease (70.5%, 95% CI 59.1-83.9% vs. 96.8%, 95% CI 94.1-99.64%, respectively). CONCLUSION: Meta-analysis of revised AJCC staging for DTC, incorporating diverse populations, demonstrates redistribution of patients toward earlier clinical stages and better stratification of disease-specific mortality risk, specifically among patients now classified with stage II and III disease. IMPLICATIONS FOR PRACTICE: This study provides updated estimates of disease-specific survival for patients with differentiated thyroid cancer determined by the American Joint Committee on Cancer staging system that are generalizable to broader populations and support improved stratification using the recently revised criteria.


Asunto(s)
Adenocarcinoma , Neoplasias de la Tiroides , Humanos , Estadificación de Neoplasias , Pronóstico , Neoplasias de la Tiroides/patología , Estados Unidos
2.
Nat Methods ; 11(5): 545-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24633409

RESUMEN

X-ray free-electron laser (XFEL) sources enable the use of crystallography to solve three-dimensional macromolecular structures under native conditions and without radiation damage. Results to date, however, have been limited by the challenge of deriving accurate Bragg intensities from a heterogeneous population of microcrystals, while at the same time modeling the X-ray spectrum and detector geometry. Here we present a computational approach designed to extract meaningful high-resolution signals from fewer diffraction measurements.


Asunto(s)
Rayos Láser , Sustancias Macromoleculares/química , Bacillus/enzimología , Calcio/química , Calibración , Simulación por Computador , Cristalización , Cristalografía por Rayos X , Electrones , Diseño de Equipo , Funciones de Verosimilitud , Modelos Químicos , Conformación Molecular , Muramidasa/química , Nanotecnología , Reproducibilidad de los Resultados , Programas Informáticos , Termolisina/química , Rayos X , Zinc/química
3.
J Radiol Case Rep ; 9(10): 26-34, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26629291

RESUMEN

Post-transplant lymphoproliferative disorder occurs in approximately one percent of kidney transplant recipients. We evaluated a seventy-seven year-old man with a solid mass in his transplant kidney. On contrast enhanced ultrasound, the mass enhanced but remained persistently hypovascular throughout exam. The enhancement pattern of the mass differed from that typical of clear cell renal cell carcinoma, the main differential diagnosis. Final pathology after partial nephrectomy confirmed post-transplant lymphoproliferative disorder. This is the first report of contrast enhanced ultrasound findings in a renal mass diagnosed as post-transplant lymphoproliferative disorder. Contrast enhanced ultrasound has a promising role in imaging of renal masses, particularly relevant in transplant patients due to the lack of nephrotoxicity.


Asunto(s)
Trasplante de Riñón/efectos adversos , Trastornos Linfoproliferativos/diagnóstico por imagen , Trastornos Linfoproliferativos/etiología , Anciano , Carcinoma de Células Renales/diagnóstico , Diagnóstico Diferencial , Humanos , Neoplasias Renales/diagnóstico , Trastornos Linfoproliferativos/cirugía , Masculino , Nefrectomía , Ultrasonografía
4.
Nat Commun ; 5: 4371, 2014 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-25006873

RESUMEN

The dioxygen we breathe is formed by light-induced oxidation of water in photosystem II. O2 formation takes place at a catalytic manganese cluster within milliseconds after the photosystem II reaction centre is excited by three single-turnover flashes. Here we present combined X-ray emission spectra and diffraction data of 2-flash (2F) and 3-flash (3F) photosystem II samples, and of a transient 3F' state (250 µs after the third flash), collected under functional conditions using an X-ray free electron laser. The spectra show that the initial O-O bond formation, coupled to Mn reduction, does not yet occur within 250 µs after the third flash. Diffraction data of all states studied exhibit an anomalous scattering signal from Mn but show no significant structural changes at the present resolution of 4.5 Å. This study represents the initial frames in a molecular movie of the structural changes during the catalytic reaction in photosystem II.


Asunto(s)
Fotosíntesis/fisiología , Espectrometría por Rayos X/métodos , Agua/metabolismo , Difracción de Rayos X/métodos , Cianobacterias/metabolismo , Modelos Químicos , Oxidación-Reducción , Oxígeno/metabolismo , Complejo de Proteína del Fotosistema II/química , Complejo de Proteína del Fotosistema II/metabolismo
5.
Science ; 340(6131): 491-5, 2013 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-23413188

RESUMEN

Intense femtosecond x-ray pulses produced at the Linac Coherent Light Source (LCLS) were used for simultaneous x-ray diffraction (XRD) and x-ray emission spectroscopy (XES) of microcrystals of photosystem II (PS II) at room temperature. This method probes the overall protein structure and the electronic structure of the Mn4CaO5 cluster in the oxygen-evolving complex of PS II. XRD data are presented from both the dark state (S1) and the first illuminated state (S2) of PS II. Our simultaneous XRD-XES study shows that the PS II crystals are intact during our measurements at the LCLS, not only with respect to the structure of PS II, but also with regard to the electronic structure of the highly radiation-sensitive Mn4CaO5 cluster, opening new directions for future dynamics studies.


Asunto(s)
Compuestos de Manganeso/química , Óxidos/química , Complejo de Proteína del Fotosistema II/química , Cristalografía por Rayos X/métodos , Cianobacterias/enzimología , Electrones , Luz , Oxidación-Reducción , Complejo de Proteína del Fotosistema II/efectos de la radiación , Conformación Proteica , Espectrometría por Rayos X/métodos , Temperatura , Agua/química , Difracción de Rayos X/métodos
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