MRI and PET/MRI in hematologic malignancies

The role of MRI differs considerably between the three main groups of hematological malignancies: lymphoma, leukemia, and myeloma. In myeloma, whole-body MRI (WB-MRI) is recognized as a highly sensitive test for the assessment of myeloma, and is also endorsed by clinical guidelines, especially for detection and staging. In lymphoma, WB-MRI is presently not recommended, and merely serves as an alternative technique to the current standard imaging test, [18F]FDG-PET/CT, especially in pediatric patients. Even for lymphomas with variable FDG avidity, such as extranodal mucosa-associated lymphoid tissue lymphoma (MALT), contrast-enhanced computed tomography (CT), but not WB-MRI, is presently recommended, despite the high sensitivity of diffusion-weighted MRI and its ability to capture treatment response that has been reported in the literature. In leukemia, neither MRI nor any other cross-sectional imaging test (including positron emission tomography [PET]) is currently recommended outside of clinical trials. This review article discusses current clinical applications as well as the main research topics for MRI, as well as PET/MRI, in the field of hematological malignancies, with a focus on functional MRI techniques such as diffusion-weighted imaging and dynamic contrast-enhanced MRI, on the one hand, and novel, non-FDG PET imaging probes such as the CXCR4 radiotracer [68Ga]Ga-Pentixafor and the amino acid radiotracer [11C]methionine, on the other hand. Level of Evidence: 5. Technical Efficacy Stage: 3

Exemplarily view on selected fluorescence textile products

Fluorescent materials emit light of higher wavelength, in case of illumination with light exhibiting lower wavelength. In many commercial applications, fluorescent materials transfer non-visible ultraviolet (UV) light into visible light. By this an additional color effect and higher visibility is reached. One typical field for application of fluorescence dyes is the textile area. Here, fluorescent textile products are manifold used and offered, e.g. for brightening effects, light effects and UV protection. With this background, the aim of the current study is the investigation of typical commercially available textile products with fluorescent properties. For this, four different polyester fiber-based materials of different coloration and purpose are selected for investigation. Investigations are performed by illumination under different illumination arrangements with UV light and visible light. CIE-Lab measurements are done. Further, scanning electronic microscopy (SEM) and Fourier Transform infrared (FT-IR) spectroscopy are used. Light emission and excitation of the samples is recorded by fluorescence spectroscopy. 2D fluorescence spectroscopy is performed. The chemical composition of the investigated textile samples is determined by using electron dispersive spectroscopy (EDS). For all investigated commercial textile products, the light emission during illumination with UV light is extraordinary strong. The color appearance can be enhanced strongly by this fluorescence effect. Beside the absorption of UV light by the present fluorescence dyes, also the presence of titanium dioxide supports an UV protective property of the textile samples. Finally, it can be concluded that fluorescent fiber materials are well established products for advanced and functional textiles. These materials can be even found in cost effective and everyday consumer products

Planeamiento estratégico de MODASA como respuesta al impacto de la llegada del gas de Camisea a Lima

Se realizaron entrevistas y El objetivo principal de la presente tesis es la elaboración de una propuesta estratégica de Motores Diesel Andinos S.A. (MODASA) para los próximos cinco años, como respuesta a la llegada del gas natural de Camisea en el sector de transporte vehicular público, constituido principalmente por los buses que prestan servicio de transporte público de pasajeros y en el sector de transporte vehicular privado conformado en su mayoría por vehículos ligeros como taxis y automóviles de uso particular. Es para MODASA importante establecer el verdadero impacto del gas natural de Camisea pues se estima, que así como el diesel N° 2 reemplazó en su momento a las gasolinas, el gas natural reemplazará de alguna u otra forma a los derivados del petróleo, lo cual constituye una oportunidad de negocio para la empresa. La metodología utilizada bajo la cual se sustenta el análisis y desarrollo del planeamiento estratégico aquí presentado se basa en la aplicación del proceso de dirección estratégica propuesta por Fred R. David , la cual consistió, en primer lugar en describir y analizar el entorno sobre el cual se desenvuelve MODASA, elaborar su análisis interno, proponiendo el plan de negocios requerido y su posterior implementación a través de sus estrategias y objetivos de corto y largo plazo. encuestas a diferentes especialistas en la materia, las cuales nos permitieron enriquecer y sustentar el presente trabajo. En la actualidad se observa variaciones constantes en el precio del petróleo con tendencia al alza lo que origina inflación en países como el Perú ya que son precio aceptantes y están sujetos a sus variaciones. Dada esta coyuntura, es que los países que cuentan con otros recursos, como el gas natural, introducen políticas energéticas que les permite diversificar sus fuentes de energía. El estado peruano, en Abril de 1999, promulgó el Reglamento de la Ley de Promoción de la Industria del Gas Natural, como una muestra de su voluntad de impulsar el desarrollo del gas de natural de Camisea. El modelo de migración del uso de gasolinas a gas natural en el transporte vehicular privado en Argentina, presenta similitudes con la realidad peruana, lo cual permite demostrar que existen las condiciones necesarias para que se produzca en el Perú dicha migración. Estas similitudes vienen dadas por la gran diferencia entre el precio del gas natural y los combustibles líquidos, la participación conjunta del estado y la actividad privada, el desarrollo de las reglamentaciones y normas y la existencia de una red de transporte y distribución. Estas condiciones permiten a los especialistas formular pronósticos de demanda de kits de conversión de vehículos a gasolina, los cuales han sido tomados en el presente trabajo como insumo para la formulación de objetivos de largo plazo. Adicionalmente, el sistema de transporte urbano actual es considerado caótico pero con una propuesta de mejora presentada por la Municipalidad Metropolitana de Lima a través de su Proyecto de Transporte Urbano de Lima (Protransporte). La demanda originada por este proyecto constituye otro insumo para la elaboración de los objetivos a largo plazo. Al realizar la auditoría interna de MODASA se pudo observar que las fortalezas principales de la empresa vienen dadas por su alto know how en el desarrollo de aplicaciones de motores, su personal con alto nivel técnico, sus procesos consolidados y respetados por el personal y su proceso de planeamiento y fabricación logístico eficiente, en tanto sus debilidades más importantes son la ausencia de planes estratégicos, la desmotivación del personal por la ausencia de planes de desarrollo y la falta de estrategias de marketing y política de desarrollo de nuevos productos. La matriz cuantitativa del planeamiento estratégico nos permitirá establecer las estrategias más adecuadas, alineadas con la nueva visión propuesta para la empresa. Dichas estrategias están enfocadas a establecer sociedades con operadores de transporte para participación conjunta en el programa de transporte urbano de Lima, buscar marcas para ofertas de buses articulados a diesel N° 2 o a gas natural, joint venture con fabricantes de buses y carrocerías a nivel mundial, alianza con marcas reconocidas de motores vehiculares, diversificar línea de buses con motores a gas natural y comercializar e instalar kits de conversión a GNV. A fin de realizar una adecuada implementación de las estrategias seleccionadas se ha planteado para cada objetivo de largo plazo, objetivos de corto plazo, las políticas relacionadas y se ha estimado los recursos requeridos. Finalmente, la evaluación económica arroja resultados favorables que impulsarían la participación de MODASA en el nuevo mercado de combustión interna conformado por el gas natural.Tesi

Endoscopic imaging of Cerenkov luminescence

We demonstrate feasibility of endoscopic imaging of Cerenkov light originated when charged nuclear particles, emitted from radionuclides, travel through a biological tissue of living subjects at superluminal velocity. The endoscopy imaging system consists of conventional optical fiber bundle/ clinical endoscopes, an optical imaging lens system, and a sensitive low-noise charge coupled device (CCD) camera. Our systematic studies using phantom samples show that Cerenkov light from as low as 1 µCi of radioactivity emitted from 18F-Fluorodeoxyglucose (FDG) can be coupled and transmitted through conventional optical fibers and endoscopes. In vivo imaging experiments with tumor bearing mice, intravenously administered with 18F-FDG, further demonstrated that Cerenkov luminescence endoscopy is a promising new tool in the field of endoscopic molecular imaging

CRESCIMENTO E BIOMASSA DE INDIVÍDUOS JOVENS DE Cabralea canjerana (Vell.) Mart.

Este trabalho possui como objetivo ajustar e selecionar modelos matemáticos capazes de estimar o incremento periódico em área basal, o volume e biomassa de indivíduos jovens de Cabralea canjerana (Vell.) Mart. O estudo foi desenvolvido no município de Agudo - RS, em uma área de Floresta Estacional Decidual. Para análise de crescimento foram utilizadas 19 árvores. A quantificação da biomassa foi obtida pelo método direto com 14 árvores da espécie. No cálculo de volume foram selecionadas e cubadas 12 árvores pelo método de Smalian. Na modelagem da estimativa das variáveis incremento periódico em área basal, volume, biomassa total, biomassa da madeira e biomassa foliar foram testados seis modelos matemáticos. Para avaliação das equações ajustadas foi utilizada a menor soma dos escores dos critérios estatísticos: coeficiente de determinação, erro padrão da estimativa e coeficiente de variação em percentagem, em conjunto com a análise gráfica da dispersão dos resíduos. O modelo matemático de Schumacher-Hall obteve melhor ajuste nas estimativas de incremento periódico em área basal, volume, biomassas total e da madeira. A equação definida para o incremento periódico em área basal foi lnIPg=-0,149+1,777.lnDAP-0,815.lnHt. A equação de volume selecionada foi lnV=-9.382+1.583.lnDAP+1.064.lnHt. As equações definidas para biomassa aérea total e biomassa da madeira foram lnBt=-3,769+1,779.lnDAP+1,131lnHt e lnBm=-3,986+1,784.lnDAP+1,198lnHt, respectivamente. As equações para estimativa de biomassa foliar obtiveram estatísticas insatisfatórias e apresentaram elevados valores de coeficiente de variação em percentagem

Is local review of positron emission tomography scans sufficient in diffuse large B-cell lymphoma clinical trials? A CALGB 50303 analysis

BACKGROUND: Quantitative methods of Fluorodeoxyglucose Positron Emission Tomography (FDG-PET) interpretation, including the percent change in FDG uptake from baseline (ΔSUV), are under investigation in lymphoma to overcome challenges associated with visual scoring systems (VSS) such as the Deauville 5-point scale (5-PS). METHODS: In CALGB 50303, patients with DLBCL received frontline R-CHOP or DA-EPOCH-R, and although there were no significant associations between interim PET responses assessed centrally after cycle 2 (iPET) using 5-PS with progression-free survival (PFS) or overall survival (OS), there were significant associations between central determinations of iPET ∆SUV with PFS/OS. In this patient cohort, we retrospectively compared local vs central iPET readings and evaluated associations between local imaging data and survival outcomes. RESULTS: Agreement between local and central review was moderate (kappa = 0.53) for VSS and high (kappa = 0.81) for ∆SUV categories (\u3c66% vs. ≥66%). ∆SUV ≥66% at iPET was significantly associated with PFS (p = 0.03) and OS (p = 0.002), but VSS was not. Associations with PFS/OS when applying local review vs central review were comparable. CONCLUSIONS: These data suggest that local PET interpretation for response determination may be acceptable in clinical trials. Our findings also highlight limitations of VSS and call for incorporation of more objective measures of response assessment in clinical trials

Positron emission tomography–CT prediction of occult nodal metastasis in recurrent laryngeal cancer

BackgroundThe purpose of this study was to evaluate the predictive value of positron emission tomography (PET)‐CT in identifying occult nodal metastasis in clinically and radiographically N0 patients with recurrent laryngeal cancer undergoing salvage laryngectomy.MethodsRetrospective review of 46 clinically and radiographically N0 patients with recurrent laryngeal cancer who underwent a PET‐CT examination before salvage laryngectomy with neck dissection from January 1, 2002, to December 31, 2014, was performed.ResultsTwo patients (16.7%) had true‐positive PET‐CT results, whereas 10 patients (83.3%) had false‐negative scans, 1 patient (2.9%) had a false‐positive result and 33 patients (97.1%) had a true‐negative PET‐CT. The sensitivity of PET‐CT was 16.7% (95% confidence interval [CI], 3.5% to 46.0%) with a specificity of 97.1% (95% CI, 83.8% to 99.9%), positive predictive value (PPV) of 66.7% (95% CI, 20.2% to 94.4%), and negative predictive value (NPV) of 76.7% (95% CI, 62.1% to 87.0%).ConclusionPET‐CT has poor sensitivity and NPV making PET‐CT an imperfect predictor of nodal disease in recurrent laryngeal cancer. © 2017 Wiley Periodicals, Inc. Head Neck 39: 980–987, 2017Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136682/1/hed24719.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136682/2/hed24719_am.pd

Scanning X-ray nanodiffraction: from the experimental approach towards spatially resolved scattering simulations

An enhancement on the method of X-ray diffraction simulations for applications using nanofocused hard X-ray beams is presented. We combine finite element method, kinematical scattering calculations, and a spot profile of the X-ray beam to simulate the diffraction of definite parts of semiconductor nanostructures. The spot profile could be acquired experimentally by X-ray ptychography. Simulation results are discussed and compared with corresponding X-ray nanodiffraction experiments on single SiGe dots and dot molecules